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Sample records for term vegetation trends

  1. Short term fluctuations and succession trends in tropical floodplain vegetation measured by correspondence analysis

    Directory of Open Access Journals (Sweden)

    Anderson Medeiros dos Santos

    2008-08-01

    Full Text Available The aim of this work was to study the aquatic macrophytes community development to distinguish the fluctuations from succession trends at different temporal and spatial scales in the Upper Paraná River floodplain. The samples were collected quarterly from May 2000 to March 2002 in seven lakes with different degrees of connectivity from the main river channel and analyzed by between-class correspondence analysis. It was difficult to establish any pattern of community development at local scale but at a higher level of organization, disconnected lakes were characterized by fluctuation of the floristic composition. Connected lakes showed a straight trajectory, indicating that succession was occurring at these sites. Probably the income of propagules and diaspores from the river into connected lakes was the driving force of the observed change in community composition.Trabalhos sobre sucessão ecológica foram realizados principalmente com ecologia vegetal de plantas terrestres, onde a maioria das teorias foram concebidas. Poucos estudos abordam a vegetação de áreas alagáveis especialmente no Brasil. Este trabalho investigou o desenvolvimento da comunidade de macrófitas aquáticas tentando distinguir flutuações populacionais de tendências sucessionais em diferentes escalas temporal e espacial na planície de inundação do Alto Rio Paraná. As amostras foram coletadas a cada três meses, de maio de 2000 a março de 2002, em 7 lagoas com diferentes graus de conectividade com a calha principal dos rios, e analisadas pela análise de correspondência (CA entre-classes. Foi difícil estabelecer qualquer padrão de desenvolvimento da comunidade sob uma escala local, mas em uma escala mais ampla, as lagoas desconectadas foram caracterizadas pela flutuação da composição florística. As lagoas conectadas apresentaram uma trajetória retilínea no diagrama da CA, indicando que a sucessão estava ocorrendo nestes locais. Provavelmente, o aporte

  2. Long-term trends in submersed aquatic vegetation (SAV) in Chesapeake Bay, USA, related to water quality

    Science.gov (United States)

    Orth, Robert J.; Williams, Michael R.; Marion, Scott R.; Wilcox, David J.; Carruthers, Tim J.B.; Moore, Kenneth A.; Kemp, W.M.; Dennison, William C.; Rybicki, Nancy B.; Peter Bergstrom,; Batiuk, Richard A.

    2010-01-01

    Chesapeake Bay supports a diverse assemblage of marine and freshwater species of submersed aquatic vegetation (SAV) whose broad distributions are generally constrained by salinity. An annual aerial SAV monitoring program and a bi-monthly to monthly water quality monitoring program have been conducted throughout Chesapeake Bay since 1984. We performed an analysis of SAV abundance and up to 22 environmental variables potentially influencing SAV growth and abundance (1984-2006). Historically, SAV abundance has changed dramatically in Chesapeake Bay, and since 1984, when SAV abundance was at historic low levels, SAV has exhibited complex changes including long-term (decadal) increases and decreases, as well as some large, single-year changes. Chesapeake Bay SAV was grouped into three broad-scale community-types based on salinity regime, each with their own distinct group of species, and detailed analyses were conducted on these three community-types as well as on seven distinct case-study areas spanning the three salinity regimes. Different trends in SAVabundance were evident in the different salinity regimes. SAV abundance has (a) continually increased in the low-salinity region; (b) increased initially in the medium-salinity region, followed by fluctuating abundances; and (c) increased initially in the high-salinity region, followed by a subsequent decline. In all areas, consistent negative correlations between measures of SAV abundance and nitrogen loads or concentrations suggest that meadows are responsive to changes in inputs of nitrogen. For smaller case-study areas, different trends in SAV abundance were also noted including correlations to water clarity in high-salinity case-study areas, but nitrogen was highly correlated in all areas. Current maximum SAV coverage for almost all areas remain below restoration targets, indicating that SAV abundance and associated ecosystem services are currently limited by continued poor water quality, and specifically high

  3. The long-term trends (1982-2006) in vegetation greenness of the alpine ecosystem in the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Zhang, Li; Guo, Huadong; Wang, Cuizhen; Ji, Lei; Li, Jing; Wang, Kun; Dai, Lin

    2014-01-01

    The increased rate of annual temperature in the Qinghai-Tibetan Plateau exceeded all other areas of the same latitude in recent decades. The influence of the warming climate on the alpine ecosystem of the plateau was distinct. An analysis of alpine vegetation under changes in climatic conditions was conducted in this study. This was done through an examination of vegetation greenness and its relationship with climate variability using the Advanced Very High Resolution Radiometer satellite imagery and climate datasets. Vegetation in the plateau experienced a positive trend in greenness, with 18.0 % of the vegetated areas exhibiting significantly positive trends, which were primarily located in the eastern and southwestern parts of the plateau. In grasslands, 25.8 % of meadows and 14.1 % of steppes exhibited significant upward trends. In contrast, the broadleaf forests experienced a trend of degradation. Temperature, particularly summer temperature, was the primary factor promoting the vegetation growth in the plateau. The wetter and warmer climate in the east contributed to the favorable conditions for vegetation. The alpine meadow was mostly sensitive to temperature, while the steppes were sensitive to both temperature and precipitation. Although a warming climate was expected to be beneficial to vegetation growth in the alpine region, the rising temperature coupled with reduced precipitation in the south did not favor vegetation growth due to low humidity and poor soil moisture conditions.

  4. ROOT VEGETABLES, BREEDING TRENDS, RESULTS

    Directory of Open Access Journals (Sweden)

    M. I. Fedorova

    2017-01-01

    Full Text Available The main advantage of root vegetables is their unique specificity and high economic importance. The benefits and medicinal properties of root vegetables being highly demanded by the market requirements to the commodity are highlighted in the article. The main directions of breeding program for root vegetable crops, including species of Apiaceae family with carrot, parsnips; Chenopodioideae family with red beet; Brassicaceae family with radish, Daikon, Raphanus sativus L. var. lobo Sazonova & Stank, turnip and rutabaga. Initial breeding accessions of carrot, red beet, radish, Daikon, Raphanus sativus L. var. lobo Sazonova & Stank, turnip and rutabaga have been selected out to be used for breeding program for heterosis. The mf and ms breeding lines were developed, and with the use of them the new gene pool was created. Variety supporting breeding program and methods were also proposed. 

  5. Assessment of vegetation trends in drylands from time series of earth observation data

    NARCIS (Netherlands)

    Fensholt, R.; Horion, S.; Tagesson, T.; Ehammer, A.; Grogan, K.; Tian, F.; Huber, S.; Verbesselt, J.; Prince, S.D.; Tucker, C.J.; Rasmussen, K.

    2015-01-01

    This chapter summarizes approaches to the detection of dryland vegetation change and methods for observing spatio-temporal trends from space. An overview of suitable long-term Earth Observation (EO) based datasets for assessment of global dryland vegetation trends is provided and a status map of

  6. Chapter 3: Status and trends of vegetation

    Science.gov (United States)

    James M. Guldin; Frank R. Thompson; Lynda L. Richards; Kyra C. Harper

    1999-01-01

    This chapter provides information about the vegetation cover of the Assessment area. The types and areal extent of vegetation in the Highlands are of interest for many reasons. Vegetation cover largely determines the availability of habitat for terrestrial animals, plants, and other organisms. Vegetation cover strongly influences what uses {e.g., timber, forage,...

  7. Long-term trends in vegetation phenology and productivity over Namaqualand using the GIMMS AVHRR NDVI3g data from 1982 to 2011

    CSIR Research Space (South Africa)

    Davis, CL

    2017-07-01

    Full Text Available Vegetation monitoring of arid and semi-arid environments using remotely sensed vegetation indices over long periods of time is essential to improve the understanding of the processes related to change. In this paper, 30 years of biweekly AVHRR NDVI3...

  8. Recent Change of Vegetation Growth Trend in China

    Science.gov (United States)

    Peng, Shushi; Chen, Anping; Xu, Liang; Cao, Chunxiang; Fang, Jingyun; Myneni, Ranga B.; Pinzon, Jorge E.; Tucker, COmpton J.; Piao, Shilong

    2011-01-01

    Using satellite-derived normalized difference vegetation index (NDVI) data, several previous studies have indicated that vegetation growth significantly increased in most areas of China during the period 1982-99. In this letter, we extended the study period to 2010. We found that at the national scale the growing season (April-October) NDVI significantly increased by 0.0007/yr from 1982 to 2010, but the increasing trend in NDVI over the last decade decreased in comparison to that of the 1982-99 period. The trends in NDVI show significant seasonal and spatial variances. The increasing trend in April and May (AM) NDVI (0.0013/yr is larger than those in June, July and August (JJA) (0.0003/yr) and September and October (SO) (0.0008/yr). This relatively small increasing trend of JJA NDVI during 1982-2010 compared with that during 1982-99 (0.0012/yr) (Piao et al 2003 J. Geophys. Res.-Atmos. 108 4401) implies a change in the JJA vegetation growth trend, which significantly turned from increasing (0.0039/yr) to slightly decreasing (0:0002/yr) in 1988. Regarding the spatial pattern of changes in NDVI, the growing season NDVI increased (over 0.0020/yr) from 1982 to 2010 in southern China, while its change was close to zero in northern China, as a result of a significant changing trend reversal that occurred in the 1990s and early 2000s. In northern China, the growing season NDVI significantly increased before the 1990s as a result of warming and enhanced precipitation, but decreased after the 1990s due to drought stress strengthened by warming and reduced precipitation. Our results also show that the responses of vegetation growth to climate change vary across different seasons and ecosystems.

  9. Recent change of vegetation growth trend in China

    International Nuclear Information System (INIS)

    Peng Shushi; Fang Jingyun; Piao Shilong; Chen, Anping; Xu Liang; Myneni, Ranga B; Cao Chunxiang; Pinzon, Jorge E; Tucker, Compton J

    2011-01-01

    Using satellite-derived normalized difference vegetation index (NDVI) data, several previous studies have indicated that vegetation growth significantly increased in most areas of China during the period 1982–99. In this letter, we extended the study period to 2010. We found that at the national scale the growing season (April–October) NDVI significantly increased by 0.0007 yr −1 from 1982 to 2010, but the increasing trend in NDVI over the last decade decreased in comparison to that of the 1982–99 period. The trends in NDVI show significant seasonal and spatial variances. The increasing trend in April and May (AM) NDVI (0.0013 yr −1 ) is larger than those in June, July and August (JJA) (0.0003 yr −1 ) and September and October (SO) (0.0008 yr −1 ). This relatively small increasing trend of JJA NDVI during 1982–2010 compared with that during 1982–99 (0.0012 yr −1 ) (Piao et al 2003 J. Geophys. Res.—Atmos. 108 4401) implies a change in the JJA vegetation growth trend, which significantly turned from increasing (0.0039 yr −1 ) to slightly decreasing ( − 0.0002 yr −1 ) in 1988. Regarding the spatial pattern of changes in NDVI, the growing season NDVI increased (over 0.0020 yr −1 ) from 1982 to 2010 in southern China, while its change was close to zero in northern China, as a result of a significant changing trend reversal that occurred in the 1990s and early 2000s. In northern China, the growing season NDVI significantly increased before the 1990s as a result of warming and enhanced precipitation, but decreased after the 1990s due to drought stress strengthened by warming and reduced precipitation. Our results also show that the responses of vegetation growth to climate change vary across different seasons and ecosystems.

  10. Drivers of Global Vegetation Biomass Trends between 1988 and 2008

    KAUST Repository

    McCabe, Matthew

    2013-12-01

    Vegetation optical depth (VOD) is an indicator of the vegetation water content of both woody and leaf components in terrestrial biomass as derived from passive microwave observations. VOD is distinctly different from products derived from optical remote sensing: it is less prone to saturation in dense canopy; is sensitive to both photosynthetic and non-photosynthetic biomass; is less affected by atmospheric conditions; and is of coarser spatial resolution. Here, VOD retrievals from a series of sensors are blended to produce a time series from 1988 through to 2008, and a global analysis is undertaken to quantify and attribute global VOD trends over the same period. We conduct Mann-Kendall linear trend tests on annual average VOD to identify regions of significant change. Patterns for these regions were evaluated against independent datasets to diagnose the underlying cause of the observed trends. Results indicate that: (1) over grassland and shrubland, VOD patterns correspond strongly to temporal precipitation patterns; (2) over croplands, annual average VOD shows a general increase that corresponds to reported crop yield patterns and can be attributed to a combination of precipitation patterns and agricultural improvement; (3) over humid tropical forest, the spatial pattern of VOD decline agrees well with deforestation patterns identified in previous studies; and (4) over boreal forests, regional VOD declines can be attributed to a combination of fires and logging. We conclude that VOD can be used to estimate and interpret global changes in total above ground vegetation biomass. We expect that this new observationally based remote sensing data source will be of considerable interest to hydrological, agricultural, climate change and carbon cycle studies, and provide new insights into these and related process investigations.

  11. Drivers of Global Vegetation Biomass Trends between 1988 and 2008

    KAUST Repository

    McCabe, Matthew; Liu, Yi; Evans, Jason; De Jeu, Richard; van Dijk, Albert

    2013-01-01

    Vegetation optical depth (VOD) is an indicator of the vegetation water content of both woody and leaf components in terrestrial biomass as derived from passive microwave observations. VOD is distinctly different from products derived from optical remote sensing: it is less prone to saturation in dense canopy; is sensitive to both photosynthetic and non-photosynthetic biomass; is less affected by atmospheric conditions; and is of coarser spatial resolution. Here, VOD retrievals from a series of sensors are blended to produce a time series from 1988 through to 2008, and a global analysis is undertaken to quantify and attribute global VOD trends over the same period. We conduct Mann-Kendall linear trend tests on annual average VOD to identify regions of significant change. Patterns for these regions were evaluated against independent datasets to diagnose the underlying cause of the observed trends. Results indicate that: (1) over grassland and shrubland, VOD patterns correspond strongly to temporal precipitation patterns; (2) over croplands, annual average VOD shows a general increase that corresponds to reported crop yield patterns and can be attributed to a combination of precipitation patterns and agricultural improvement; (3) over humid tropical forest, the spatial pattern of VOD decline agrees well with deforestation patterns identified in previous studies; and (4) over boreal forests, regional VOD declines can be attributed to a combination of fires and logging. We conclude that VOD can be used to estimate and interpret global changes in total above ground vegetation biomass. We expect that this new observationally based remote sensing data source will be of considerable interest to hydrological, agricultural, climate change and carbon cycle studies, and provide new insights into these and related process investigations.

  12. Attribution of trends in global vegetation greenness from 1982 to 2011

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    Zhu, Z.; Xu, L.; Bi, J.; Myneni, R.; Knyazikhin, Y.

    2012-12-01

    Time series of remotely sensed vegetation indices data provide evidence of changes in terrestrial vegetation activity over the past decades in the world. However, it is difficult to attribute cause-and-effect to vegetation trends because variations in vegetation productivity are driven by various factors. This study investigated changes in global vegetation productivity first, and then attributed the global natural vegetation with greening trend. Growing season integrated normalized difference vegetation index (GSI NDVI) derived from the new GIMMS NDVI3g dataset (1982-2011was analyzed. A combined time series analysis model, which was developed from simper linear trend model (SLT), autoregressive integrated moving average model (ARIMA) and Vogelsang's t-PST model shows that productivity of all vegetation types except deciduous broadleaf forest predominantly showed increasing trends through the 30-year period. The evolution of changes in productivity in the last decade was also investigated. Area of greening vegetation monotonically increased through the last decade, and both the browning and no change area monotonically decreased. To attribute the predominant increase trend of productivity of global natural vegetation, trends of eight climate time series datasets (three temperature, three precipitation and two radiation datasets) were analyzed. The attribution of trends in global vegetation greenness was summarized as relaxation of climatic constraints, fertilization and other unknown reasons. Result shows that nearly all the productivity increase of global natural vegetation was driven by relaxation of climatic constraints and fertilization, which play equally important role in driving global vegetation greenness.; Area fraction and productivity change fraction of IGBP vegetation land cover classes showing statistically significant (10% level) trend in GSI NDVIt;

  13. Price Trends Are Similar for Fruits, Vegetables, and Snack Foods

    OpenAIRE

    Kuchler, Fred; Stewart, Hayden

    2008-01-01

    An increase in the price of fruits and vegetables relative to less healthy foods could reduce consumers’ incentives to purchase fruits and vegetables and result in less healthy diets. Whether such a change in relative prices and incentives has occurred in the United States is difficult to prove because of substantial quality improvements in many fresh fruits and vegetables. For commonly consumed fresh fruits and vegetables for which quality has remained fairly constant, analysis of price tren...

  14. Trend shifts in satellite-derived vegetation growth in Central Eurasia, 1982-2013.

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    Xu, Hao-Jie; Wang, Xin-Ping; Yang, Tai-Bao

    2017-02-01

    Central Eurasian vegetation is critical for the regional ecological security and the global carbon cycle. However, climatic impacts on vegetation growth in Central Eurasia are uncertain. The reason for this uncertainty lies in the fact that the response of vegetation to climate change showed nonlinearity, seasonality and differences among plant functional types. Based on remotely sensed vegetation index and in-situ meteorological data for the years 1982-2013, in conjunction with the latest land cover type product, we analyzed how vegetation growth trend varied across different seasons and evaluated vegetation response to climate variables at regional, biome and pixel scales. We found a persistent increase in the growing season NDVI over Central Eurasia during 1982-1994, whereas this greening trend has stalled since the mid-1990s in response to increased water deficit. The stalled trend in the growing season NDVI was largely attributed by summer and autumn NDVI changes. Enhanced spring vegetation growth after 2002 was caused by rapid spring warming. The response of vegetation to climatic factors varied in different seasons. Precipitation was the main climate driver for the growing season and summer vegetation growth. Changes in temperature and precipitation during winter and spring controlled the spring vegetation growth. Autumn vegetation growth was mainly dependent on the vegetation growth in summer. We found diverse responses of different vegetation types to climate drivers in Central Eurasia. Forests were more responsive to temperature than to precipitation. Grassland and desert vegetation responded more strongly to precipitation than to temperature in summer but more strongly to temperature than to precipitation in spring. In addition, the growth of desert vegetation was more dependent on winter precipitation than that of grasslands. This study has important implications for improving the performance of terrestrial ecosystem models to predict future vegetation

  15. Recent shifts in Himalayan vegetation activity trends in response to climatic change and environmental drivers

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    Mishra, N. B.; Mainali, K. P.

    2016-12-01

    Climatic changes along with anthropogenic disturbances are causing dramatic ecological impacts in mid to high latitude mountain vegetation including in the Himalayas which are ecologically sensitive environments. Given the challenges associated with in situ vegetation monitoring in the Himalayas, remote sensing based quantification of vegetation dynamics can provide essential ecological information on changes in vegetation activity that may consist of alternative sequence of greening and/or browning periods. This study utilized a trend break analysis procedure for detection of monotonic as well as abrupt (either interruption or reversal) trend changes in smoothed normalized difference vegetation index satellite time-series data over the Himalayas. Overall, trend breaks in vegetation greenness showed high spatio-temporal variability in distribution considering elevation, ecoregion and land cover/use stratifications. Interrupted greening was spatially most dominant in all Himalayan ecoregions followed by abrupt browning. Areas showing trend reversal and monotonic trends appeared minority. Trend type distribution was strongly dependent on elevation as majority of greening (with or without interruption) occurred at lower elevation areas at higher elevation were dominantly. Ecoregion based stratification of trend types highlighted some exception to this elevational dependence as high altitude ecoregions of western Himalayas showed significantly less browning compared to the ecoregions in eastern Himalaya. Land cover/use based analysis of trend distribution showed that interrupted greening was most dominant in closed needleleafed forest following by rainfed cropland and mosaic croplands while interrupted browning most dominant in closed to open herbaceous vegetation found at higher elevation areas followed by closed needleleafed forest and closed to open broad leafed evergreen forests. Spatial analysis of trend break timing showed that for majority of areas experiencing

  16. Vegetation Activity Trend and Its Relationship with Climate Change in the Three Gorges Area, China

    Directory of Open Access Journals (Sweden)

    Guifeng Han

    2013-01-01

    Full Text Available Based on SPOT/VGT NDVI time series images from 1999 to 2009 in the Three Gorges Area (TGA, we detected vegetation activity and trends using two methods, the Mann-Kendall and Slope tests. The relationships between vegetation activity trends and annual average temperature and annual total precipitation were analyzed using observational data in seven typical meteorological stations. Vegetation activity presents a distinctive uptrend during the study period, especially in Fengjie, Yunyang, Wushan, Wuxi, and Badong counties located in the midstream of the Three Gorges Reservoir. However, in the Chongqing major area (CMA and its surrounding areas and Fuling, Yichang, and part of Wanzhou, vegetation activity shows a decreasing trend as a result of urban expansion. The NDVI has two fluctuation troughs in 2004 and 2006. The annual mean temperature presents a slight overall upward trend, but the annual total precipitation does not present a significant trend. And they almost have no significant correlations with the NDVI. Therefore, temperature and precipitation are not major influences on vegetation activity change. Instead, increasing vegetation cover benefits from a number of environment protection policies and management, and ecological construction is a major factor resulting in the upward trend. In addition, resettlement schemes mitigate the impact of human activity on vegetation activity.

  17. Trends in landscape and vegetation change and implications for the Santa Cruz Watershed

    Science.gov (United States)

    Villarreal, Miguel; Norman, Laura M.; Webb, Robert H.; Turner, Raymond M.

    2013-01-01

    Monitoring and characterizing the interactive effects of land use and climate on land surface processes is a primary focus of land change science, and of particular concern in arid Wells Distribution in Shallow Groundwater Areas Pumping Trends Increase Streamflow Extent Declines 27 environments where both landscapes and livelihoods can be impacted by short-term climate variability. Using a multi-observational approach to land-change analysis that included landownership data as a proxy for land-use practices, multitemporal land-cover maps, and repeat photography dating to the late 19th century, we examine changing spatial and temporal distributions of two vegetation types with high conservation value in the southwestern United States: grasslands and riparian vegetation. Our study area is the bi-national Santa Cruz Watershed, a topographically complex watershed that straddles the Sonoran Desert and the Madrean Archipelago Ecoregions. In this presentation we focus on historical changes in vegetation and land use in grasslands and riparian areas of the Madrean Ecoregion (San Raphael Valley, Cienega Creek, Sonoita), and compare changes in these areas to changes in the warmer and drier Sonoran Ecoregion. Analysis of historical photography confirms major 20th century vegetation shifts documented in other research: woody plant encroachment, desertification of grasslands, and changing riparian and xeroriparian vegetation occurred in both ecoregions following human settlement. However, vegetation changes over the past decade appear to be more subtle and some of the past trajectories appear to be reversing; most notable are recent mesquite declines in xeroriparian and upland areas, and changes from shrubland to grassland area in the Madrean ecoregion. Land cover changes were temporally variable, reflecting broad climate changes. The most dynamic cover changes occurred during the period from 1989 to 1999, a period with two intense droughts. The degree of vegetation change

  18. Long-term monitoring of stream bank stability under different vegetation cover

    Science.gov (United States)

    Krzeminska, Dominika; Skaalsveen, Kamilla; Kerkhof, Tjibbe

    2017-04-01

    Vegetated buffer zones are common environmental measures in many countries, including Norway. The presence of riparian vegetation on stream banks not only provides ecological benefits but also influence bank slope stability, through several complex interactions between riparian vegetation and hydro - mechanical processes. The hydrological processes associated with slope stability are complex and yet difficult to quantify, especially because their transient effects (e.g. changes throughout the vegetation life cycle). Additionally, there is very limited amount of field scale research focusing on investigation of coupled hydrological and mechanical influence of vegetation on stream bank behavior, accounting for both seasonal time scale and different vegetation type, and none dedicated to marine clay soils (typically soil for Norway). In order to fill this gap we established continues, long term hydrogeological monitoring o selected cross - section within stream bank, covered with different types of vegetation, typical for Norwegian agriculture areas (grass, shrubs, and trees). The monitoring involves methods such as spatial and temporal monitoring of soil moisture conditions, ground water level and fluctuation of water level in the stream. Herein we will present first 10 months of monitoring data: observed hydrological trends and differences between three cross - sections. Moreover, we will present first modelling exercises that aims to estimate stream banks stability with accounting on presence of different vegetation types using BSTEM and HYDRUS models. With this presentation, we would like to stimulate the discussion and get feedback that could help us to improve both, our experimental set up and analysis approach.

  19. Abrupt vegetation transitions characterise long-term Amazonian peatland development

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    Roucoux, K. H.; Baker, T. R.; Gosling, W. D.; Honorio Coronado, E.; Jones, T. D.; Lahteenoja, O.; Lawson, I. T.

    2012-04-01

    Recent investigations of wetlands in western Amazonia have revealed the presence of extensive peatlands with peat deposits of up to 8 m-thick developing under a variety of vegetation types (Lähteenoja et al. 2012). Estimated to cover 150,000 km2 (Schulman et al. 1999), these peatlands make a valuable contribution to landscape and biological diversity and represent globally important carbon stores. In order to understand the processes leading to peat formation, and the sensitivity of these environments to future climatic change, it is necessary to understand their long-term history. The extent to which peatland vegetation changes over time, the stability of particular communities, the controls on transitions between vegetation types and how these factors relate to the accumulation of organic matter are not yet known. We report the first attempt to establish the long-term (millennial scale) vegetation history of a recently-described peatland site: Quistococha, a palm swamp, or aguajal, close to Iquitos in northern Peru. The vegetation is dominated by Mauritia flexuosa and Mauritiella armata and occupies a basin which is thought to be an abandoned channel of the River Amazon. We obtained a 4 m-long peat sequence from the deepest part of the basin. AMS-radiocarbon dating yielded a maximum age of 2,212 cal yr BP for the base of the peat, giving an average accumulation rate of 18 cm per century. Below the peat are 2 m of uniform, largely inorganic pale grey clays of lacustrine origin, which are underlain by an unknown thickness of inorganic sandy-silty clay of fluvial origin. Pollen analysis, carried out at c. 88-year intervals, shows the last 2,212 years to be characterised by the development of at least four distinct vegetation communities, with peat accumulating throughout. The main phases were: (1) Formation of Cyperaceae (sedge) fen coincident with peat initiation; (2) A short-lived phase of local Mauritia/Mauritiella development; (3) Development of mixed wet

  20. Assessment of land degradation using time series trend analysis of vegetation indictors in Otindag Sandy land

    International Nuclear Information System (INIS)

    Wang, H Y; Li, Z Y; Gao, Z H; Wu, J J; Sun, B; Li, C L

    2014-01-01

    Land condition assessment is a basic prerequisite for finding the degradation of a territory, which might lead to desertification under climatic and human pressures. The temporal change in vegetation productivity is a key indicator of land degradation. In this paper, taking the Otindag Sandy Land as a case, the mean normalized difference vegetation index (NDVI a ), net primary production (NPP) and vegetation rain use efficiency (RUE) dynamic trends during 2001–2010 were analysed. The Mann-Kendall test and the Correlation Analysis method were used and their sensitivities to land degradation were evaluated. The results showed that the three vegetation indicators (NDVI a , NPP and RUE) showed a downward trend with the two methods in the past 10 years and the land was degraded. For the analysis of the three vegetation indicators (NDVI a , NPP and RUE), it indicated a decreasing trend in 62.57%, 74.16% and 88.56% of the study area according to the Mann-Kendall test and in 57.85%, 68.38% and 85.29% according to the correlation analysis method. However, the change trends were not significant, the significant trends at the 95% confidence level only accounted for a small proportion. Analysis of NDVI a , NPP and RUE series showed a significant decreasing trend in 9.21%, 4.81% and 6.51% with the Mann-Kendall test. The NPP change trends showed obvious positive link with the precipitation in the study area. While the effect of the inter-annual variation of the precipitation for RUE was small, the vegetation RUE can provide valuable insights into the status of land condition and had best sensitivity to land degradation

  1. Spatial-temporal Evolution of Vegetation Coverage and Analysis of it’s Future Trends in Wujiang River Basin

    Science.gov (United States)

    Xiao, Jianyong; Bai, Xiaoyong; Zhou, Dequan; Qian, Qinghuan; Zeng, Cheng; Chen, Fei

    2018-01-01

    Vegetation coverage dynamics is affected by climatic, topography and human activities, which is an important indicator reflecting the regional ecological environment. Revealing the spatial-temporal characteristics of vegetation coverage is of great significance to the protection and management of ecological environment. Based on MODIS NDVI data and the Maximum Value Composites (MVC), we excluded soil spectrum interference to calculate Fractional Vegetation Coverage (FVC). Then the long-term FVC was used to calculate the spatial pattern and temporal variation of vegetation in Wujiang River Basin from 2000 to 2016 by using Trend analysis and Hurst index. The relationship between topography and spatial distribution of FVC was analyzed. The main conclusions are as follows: (1) The multi-annual mean vegetation coverage reveals a spatial distribution variation characteristic of low value in midstream and high level in other parts of the basin, owing a mean value of 0.6567. (2) From 2000 to 2016, the FVC of the Wujiang River Basin fluctuated between 0.6110 and 0.7380, and the overall growth rate of FVC was 0.0074/a. (3) The area of vegetation coverage tending to improve is more than that going to degrade in the future. Grass land, Arable land and Others improved significantly; karst rocky desertification comprehensive management project lead to persistent vegetation coverage improvement of Grass land, Arable land and Others. Residential land is covered with obviously degraded vegetation, resulting of urban sprawl; (4) The spatial distribution of FVC is positively correlated with TNI. Researches of spatial-temporal evolution of vegetation coverage have significant meaning for the ecological environment protection and management of the Wujiang River Basin.

  2. Emission allowances -- Long-term price trend

    International Nuclear Information System (INIS)

    Lennox, F.H.

    1994-01-01

    Estimated trends in emission allowance (EA) values have been of interest to all those affected by the Clean Air Act Amendments of 1990 since it became law in 1990. The authors published estimates of the values of EAs in December 1991, and revised their estimate in November 1992. The summary trends of the 1992 estimate is shown here. General estimates such as these are no longer useful. Everyone directly involved in complying with the Act or in buying and selling allowances has developed their own outlook on EA values. Many recent trades have been publicized. The prices from the first auction are also well known. Therefore this article is concerned only with what might happening the long-run. Once Phase 2 compliance is essentially complete and emissions roughly match Emission Allowance allocations of some 9.8 million tons annually, what pressures will there be on prices? What will be the direction of values after Phase 2 is in balance?

  3. TREND: a program using cumulative sum methods to detect long-term trends in data

    International Nuclear Information System (INIS)

    Cranston, R.J.; Dunbar, R.M.; Jarvis, R.G.

    1976-01-01

    TREND is a computer program, in FORTRAN, to investigate data for long-term trends that are masked by short-term statistical fluctuations. To do this, it calculates and plots the cumulative sum of deviations from a chosen mean. As a further aid to diagnosis, the procedure can be repeated with a summation of the cumulative sum itself. (author)

  4. Understanding Pan-Arctic Tundra Vegetation Change Through Long-term Remotely Sensed Data

    Science.gov (United States)

    Bhatt, U.; Walker, D. A.; Bieniek, P.; Raynolds, M. K.; Epstein, H. E.; Comiso, J. C.; Pinzon, J. E.; Tucker, C. J.

    2012-12-01

    The goal of this paper is to present an analysis of the seasonality of tundra vegetation variability and change using long-term remotely sensed data as well as ground based measurements and reanalyses. An increase of Pan-Arctic tundra vegetation greenness has been documented using the remotely sensed Normalized Difference Vegetation Index (NDVI). Coherent variability between NDVI, springtime coastal sea ice (passive microwave) and land surface temperatures (AVHRR) has also been established. Satellite based snow and cloud cover data sets are being incorporated into this analysis. The Arctic tundra is divided into domains based on Treshnikov divisions that are modified based on floristic provinces. There is notable heterogeneity in Pan-Arctic vegetation and climate trends, which necessitates a regional analysis. This study uses remotely sensed weekly 25-km sea ice concentration, weekly surface temperature, and bi-weekly NDVI from 1982 to 2010. The GIMMS NDVI3g data has been corrected for biases during the spring and fall, with special focus on the Arctic. Trends of Maximum NDVI (MaxNDVI), Time Integrated NDVI (TI-NDVI), Summer Warmth Index (SWI, sum of degree months above freezing during May-August), and open water area are calculated for the Pan Arctic. Remotely sensed snow data trends suggest varying patterns throughout the Arctic and may in part explain the heterogeneous MaxNDVI trends. Standard climate data (station, reanalysis, and model data) and ground observations are used in the analysis to provide additional support for hypothesized mechanisms. Overall, we find that trends over the 30-year record are changing as evidenced by the following examples from recent years. The sea ice decline has increased in Eurasia and slowed in North America. The weekly AVHRR landsurface temperatures reveal that there has been summer cooling over Eurasia and that the warming over North America has slowed. The MaxNDVI rates of change have diverged between N. America and Eurasia

  5. Interannual variations and trends in global land surface phenology derived from enhanced vegetation index during 1982-2010

    Science.gov (United States)

    Zhang, Xiaoyang; Tan, Bin; Yu, Yunyue

    2014-05-01

    Land surface phenology is widely retrieved from satellite observations at regional and global scales, and its long-term record has been demonstrated to be a valuable tool for reconstructing past climate variations, monitoring the dynamics of terrestrial ecosystems in response to climate impacts, and predicting biological responses to future climate scenarios. This study detected global land surface phenology from the advanced very high resolution radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) data from 1982 to 2010. Based on daily enhanced vegetation index at a spatial resolution of 0.05 degrees, we simulated the seasonal vegetative trajectory for each individual pixel using piecewise logistic models, which was then used to detect the onset of greenness increase (OGI) and the length of vegetation growing season (GSL). Further, both overall interannual variations and pixel-based trends were examined across Koeppen's climate regions for the periods of 1982-1999 and 2000-2010, respectively. The results show that OGI and GSL varied considerably during 1982-2010 across the globe. Generally, the interannual variation could be more than a month in precipitation-controlled tropical and dry climates while it was mainly less than 15 days in temperature-controlled temperate, cold, and polar climates. OGI, overall, shifted early, and GSL was prolonged from 1982 to 2010 in most climate regions in North America and Asia while the consistently significant trends only occurred in cold climate and polar climate in North America. The overall trends in Europe were generally insignificant. Over South America, late OGI was consistent (particularly from 1982 to 1999) while either positive or negative GSL trends in a climate region were mostly reversed between the periods of 1982-1999 and 2000-2010. In the Northern Hemisphere of Africa, OGI trends were mostly insignificant, but prolonged GSL was evident over individual climate regions during the last 3

  6. Vegetation greenness trend (2000 to 2009) and the climate controls in the Qinghai-Tibetan Plateau

    Science.gov (United States)

    Zhang, Li; Guo, Huadong; Ji, Lei; Lei, Liping; Wang, Cuizhen; Yan, Dongmei; Li, Bin; Li, Jing

    2013-01-01

    The Qinghai-Tibetan Plateau has been experiencing a distinct warming trend, and climate warming has a direct and quick impact on the alpine grassland ecosystem. We detected the greenness trend of the grasslands in the plateau using Moderate Resolution Imaging Spectroradiometer data from 2000 to 2009. Weather station data were used to explore the climatic drivers for vegetation greenness variations. The results demonstrated that the region-wide averaged normalized difference vegetation index (NDVI) increased at a rate of 0.036  yr−1. Approximately 20% of the vegetation areas, which were primarily located in the northeastern plateau, exhibited significant NDVI increase trend (p-value plateau. A strong positive relationship between NDVI and precipitation, especially in the northeastern plateau, suggested that precipitation was a favorable factor for the grassland NDVI. Negative correlations between NDVI and temperature, especially in the southern plateau, indicated that higher temperature adversely affected the grassland growth. Although a warming climate was expected to be beneficial to the vegetation growth in cold regions, the grasslands in the central and southwestern plateau showed a decrease in trends influenced by increased temperature coupled with decreased precipitation.

  7. Statistical analysis of long term spatial and temporal trends of ...

    Indian Academy of Sciences (India)

    Statistical analysis of long term spatial and temporal trends of temperature ... CGCM3; HadCM3; modified Mann–Kendall test; statistical analysis; Sutlej basin. ... Water Resources Systems Division, National Institute of Hydrology, Roorkee 247 ...

  8. Modelled long term trends of surface ozone over South Africa

    CSIR Research Space (South Africa)

    Naidoo, M

    2011-10-01

    Full Text Available timescale seeks to provide a spatially comprehensive view of trends while also creating a baseline for comparisons with future projections of air quality through the forcing of air quality models with modelled predicted long term meteorology. Previous...

  9. Changes in Remotely Sensed Vegetation Growth Trend in the Heihe Basin of Arid Northwestern China.

    Directory of Open Access Journals (Sweden)

    Wenchao Sun

    Full Text Available The Heihe River Basin (HRB is the second largest inland river basin in China, characterized by high diversity in geomorphology and irrigated agriculture in middle reaches. To improve the knowledge about the relationship between biotic and hydrological processes, this study used Global Inventory Modeling and Mapping Studies Normalized Difference Vegetation Index (NDVI data (1982-2006 to analyze spatiotemporal variations in vegetation growth by using the Mann-Kendall test together with Sen's slope estimator. The results indicate that 10.1% and 1.6% of basin area exhibit statistically significant (p < 0.05 upward and downward trends, and maximum magnitude is 0.066/10a and 0.026/10a, respectively. More specifically, an increasing trend was observed in the Qilian Mountains and Hexi Corridor and a decreasing trend detected in the transitional region between them. Increases in precipitation and temperature may be one possible reason for the changes of vegetation growth in the Qilian Mountains. And decreasing trend in transitional region may be driven by the changes in precipitation. Increases of irrigation contribute to the upward trend of NDVI for cropland in the Hexi Corridor, reflecting that agricultural development becomes more intensive. Our study demonstrates the complexity of the response of vegetation growth in the HRB to climate change and anthropogenic activities and correspondingly adopting mechanistic ecological models capable of describing both factors is favorable for reasonable predictions of future vegetation growth. It is also indicated that improving irrigation water use efficiency is one practical strategy to balance water demand between human and natural ecosystems in the HRB.

  10. Trends in global vegetation activity and climatic drivers indicate a decoupled response to climate change

    DEFF Research Database (Denmark)

    Schut, Antonius G T; Ivits, Eva; Conijn, Jacob G.

    2015-01-01

    Detailed understanding of a possible decoupling between climatic drivers of plant productivity and the response of ecosystems vegetation is required. We compared trends in six NDVI metrics (1982-2010) derived from the GIMMS3g dataset with modelled biomass productivity and assessed uncertainty...... in trend estimates. Annual total biomass weight (TBW) was calculated with the LINPAC model. Trends were determined using a simple linear regression, a Thiel-Sen medium slope and a piecewise regression (PWR) with two segments. Values of NDVI metrics were related to Net Primary Production (MODIS......-NPP) and TBWper biome and land-use type. The simple linear and Thiel-Sen trends did not differ much whereas PWR increased the fraction of explained variation, depending on the NDVI metric considered. A positive trend in TBW indicating more favorable climatic conditions was found for 24% of pixels on land...

  11. The effect of submerged aquatic vegetation expansion on a declining turbidity trend in the Sacramento-San Joaquin River Delta

    Science.gov (United States)

    Hestir, E.L.; Schoellhamer, David H.; Jonathan Greenberg,; Morgan-King, Tara L.; Ustin, S.L.

    2016-01-01

    Submerged aquatic vegetation (SAV) has well-documented effects on water clarity. SAV beds can slow water movement and reduce bed shear stress, promoting sedimentation and reducing suspension. However, estuaries have multiple controls on turbidity that make it difficult to determine the effect of SAV on water clarity. In this study, we investigated the effect of primarily invasive SAV expansion on a concomitant decline in turbidity in the Sacramento-San Joaquin River Delta. The objective of this study was to separate the effects of decreasing sediment supply from the watershed from increasing SAV cover to determine the effect of SAV on the declining turbidity trend. SAV cover was determined by airborne hyperspectral remote sensing and turbidity data from long-term monitoring records. The turbidity trends were corrected for the declining sediment supply using suspended-sediment concentration data from a station immediately upstream of the Delta. We found a significant negative trend in turbidity from 1975 to 2008, and when we removed the sediment supply signal from the trend it was still significant and negative, indicating that a factor other than sediment supply was responsible for part of the turbidity decline. Turbidity monitoring stations with high rates of SAV expansion had steeper and more significant turbidity trends than those with low SAV cover. Our findings suggest that SAV is an important (but not sole) factor in the turbidity decline, and we estimate that 21–70 % of the total declining turbidity trend is due to SAV expansion.

  12. Trends of fruit and vegetable availability in neighbourhoods in Albany, NY, USA, 2003-2012.

    Science.gov (United States)

    Hosler, Akiko S; Kammer, Jamie R

    2015-02-01

    To investigate a 9-year trend of fresh fruit and vegetable availability and factors associated with the net availability change in two contrasting neighbourhoods. Longitudinal design. Data were collected in 2003, 2009 and 2012 through in-store observations. Fresh fruit and vegetable availability was presented by weight-adjusted counts of stores having designated varieties per 10 000 population. A low-income minority neighbourhood and an adjacent middle-income racially mixed neighbourhood in Albany, NY, USA. These neighbourhoods became sites of fresh produce interventions after baseline data were collected. A total of 111, 128 and 146 eligible food stores in respective years. Fresh fruit availability (two or more varieties) increased in both neighbourhoods. Inventory expansion of existing stores and the convenience store intervention contributed to the significant increase (P for trend=0·04) of fresh fruit availability in the minority neighbourhood. Although not statistically significant (P>0·05), the availability of two or more dark-coloured fresh vegetables also increased in the mixed neighbourhood, but declined slightly in the minority neighbourhood. The secular (non-intervention) fresh vegetable availability rate ratio by neighbourhood reached 3·0 in 2012 (Pconvenience store intervention to address the fresh vegetable disparity.

  13. Recent history of trends in vegetation greenness and large-scale ecosystem disturbances in Eurasia

    International Nuclear Information System (INIS)

    Potter, Christopher; Nemani, Ramakrishna; Kumar, Vipin; Klooster, Steven

    2007-01-01

    Recent patterns of land cover and vegetation dynamics on the Euasian continent have been linked to changes in the global carbon cycle. Our study was conducted to evaluate patterns in a 19-yr record of global satellite observations of terrestrial vegetation from the Advanced Very High Resolution Radiometer (AVHRR) as a means to characterize major trends in both vegetation 'greenness' and ecosystem disturbance. The fraction absorbed of photosynthetically active radiation (FPAR) by vegetation canopies worldwide has been computed from the AVHRR at a monthly time interval from 1982 to 2000 and gridded at a spatial resolution of 8 km globally. Unlike previous studies of the AVHRR multiyear time-series of vegetation dynamics, the 8-km spatial resolution makes it possible to compare disturbance events and greenness trends at the same level of spatial detail. Positive trends in FPAR were detected throughout a major greenbelt of central-eastern Europe starting in the mid-1980s. This Eurasian greenbelt extended in a wide swath over the Urals, into the vicinity of Lake Baykal south of the central Siberian plateau, mainly along a latitude belt from 55 deg N to 65 deg N. There was also significantly positive greening in relatively large areas of Great Britain, Italy, Greece, Turkey, the Caucasus and southern India. Nonetheless, a strong downward trend in the FPAR time-series over most of Eurasia was observed by the end of the 1990s. Throughout the 19-yr time period, Eurasia was also impacted by many notable droughts and other disturbance events that could have substantially offset decadal carbon gains attributed to satellite-observed greening. Large-scale ecosystems disturbance events were identified in the FPAR time-series by locating anomalously low values (FPAR-LO) that lasted longer than 12 consecutive months at any 8-km pixel. We find verifiable evidence of numerous disturbance types across Eurasia, including regional patterns of severe droughts, forest fires and insect

  14. The Geomagnetic Control Concept of The Ionospheric Long- Term Trends

    Science.gov (United States)

    Mikhailov, A. V.

    The geomagnetic control concept has been developed to explain long-term trends of the electron concentration in the F2 and E ionospheric regions. Periods with negative and positive foF2, hmF2 and foE trends correspond to the periods of increasing or decreasing geomagnetic activity with the turning points around the end of 1950s, 1960s, and 1980s where trends change their signs. Strong latitudinal and diurnal variations revealed for the foF2 and hmF2 trends can be explained by neutral composition, temperature and thermospheric wind changes. Particle precipitation is important in the auroral zone. The newly proposed concept proceeds from a natural origin of the F2-layer trends rather than an artificial one related to the greenhouse effect. Using the proposed method a very long-term foF2 and foE trends related with general increase of geomagnetic activity in the 20th century has been revealed for the first time. The firstly revealed relationship of the foE trends with geomagnetic activity is due to nitric oxide variations at the E-region heights. This "natural" relationship of the foE trends with geomagnetic activity breaks down around 1970 on many stations presumably due to chemical polution of the upper atmosphere. The increasing rate of rocket and satellite launchings in the late 1960s is considered as a reason.

  15. Panorama 2012 - Short-term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, Armelle

    2011-12-01

    Against the background of an energy market beset by the Fukushima crisis, the Arab spring and economic uncertainty, 2011 saw dynamic growth in demand for natural gas, although developments varied widely from region to region. New trends are emerging in the gas market, and these will have both short-term and longer-term impacts on how the industry develops. (author)

  16. Trends in Global Vegetation Activity and Climatic Drivers Indicate a Decoupled Response to Climate Change.

    Directory of Open Access Journals (Sweden)

    Antonius G T Schut

    Full Text Available Detailed understanding of a possible decoupling between climatic drivers of plant productivity and the response of ecosystems vegetation is required. We compared trends in six NDVI metrics (1982-2010 derived from the GIMMS3g dataset with modelled biomass productivity and assessed uncertainty in trend estimates. Annual total biomass weight (TBW was calculated with the LINPAC model. Trends were determined using a simple linear regression, a Thiel-Sen medium slope and a piecewise regression (PWR with two segments. Values of NDVI metrics were related to Net Primary Production (MODIS-NPP and TBW per biome and land-use type. The simple linear and Thiel-Sen trends did not differ much whereas PWR increased the fraction of explained variation, depending on the NDVI metric considered. A positive trend in TBW indicating more favorable climatic conditions was found for 24% of pixels on land, and for 5% a negative trend. A decoupled trend, indicating positive TBW trends and monotonic negative or segmented and negative NDVI trends, was observed for 17-36% of all productive areas depending on the NDVI metric used. For only 1-2% of all pixels in productive areas, a diverging and greening trend was found despite a strong negative trend in TBW. The choice of NDVI metric used strongly affected outcomes on regional scales and differences in the fraction of explained variation in MODIS-NPP between biomes were large, and a combination of NDVI metrics is recommended for global studies. We have found an increasing difference between trends in climatic drivers and observed NDVI for large parts of the globe. Our findings suggest that future scenarios must consider impacts of constraints on plant growth such as extremes in weather and nutrient availability to predict changes in NPP and CO2 sequestration capacity.

  17. The Electrification of Energy: Long-Term Trends and Opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Tsao, Jeffrey Y. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fouquet, Roger [London School of Economics and Political Science (United Kingdom); Schubert, E. Fred [Rensselaer Polytechnic Inst., Troy, NY (United States)

    2017-11-01

    Here, we present and analyze three powerful long-term historical trends in energy, particularly electrical energy, as well as the opportunities and challenges associated with these trends. The first trend is from a world containing a diversity of energy currencies to one whose predominant currency is electricity, driven by electricity’s transportability, exchangeability, and steadily decreasing cost. The second trend is from electricity generated from a diversity of sources to electricity generated predominantly by free-fuel sources, driven by their steadily decreasing cost and long-term abundance. These trends necessitate a just-emerging third trend: from a grid in which electricity is transported uni-directionally, traded at near-static prices, and consumed under direct human control; to a grid in which electricity is transported bi-directionally, traded at dynamic prices, and consumed under human-tailored agential control. Early acceptance and appreciation of these trends will accelerate their remaking of humanity’s energy landscape into one in which energy is much more affordable, abundant and efficiently deployed than it is today; with major economic, geo-political, and environmental benefits to human society.

  18. Assessing future vegetation trends and restoration prospects in the Karst regions of Southwest China

    DEFF Research Database (Denmark)

    Tong, Xiaowei; Wang, Kelin; Brandt, Martin Stefan

    2016-01-01

    for conservation management by monitoring vegetation dynamics, projecting the persistence of vegetation trends and identifying areas of interest for upcoming restoration measures. In this study, we use MODIS satellite time series (2001-2013) and the Hurst exponent to classify the study area (Guizhou and Guangxi......To alleviate the severe rocky desertification and improve the ecological conditions in Southwest China, the national and local Chinese governments have implemented a series of Ecological Restoration Projects since the late 1990s. In this context, remote sensing can be a valuable tool...... on the restoration prospects and associated uncertainty of different terrain classes found in the study area. The results show that 69% of the observed trends are persistent beyond 2013, with 57% being stable, 10% positive, 5% anti-persistent positive, 3% negative, 1% anti-persistent negative and 24% uncertain. Most...

  19. Long-term vegetation monitoring for different habitats in floodplains

    Directory of Open Access Journals (Sweden)

    LANG Petra

    2014-03-01

    Full Text Available A floodplain-restoration project along the Danube between Neuburg and Ingolstadt (Germany aims to bring back water and sediment dynamic to the floodplain. The accompanied long-term monitoring has to document the changes in biodiversity related to this new dynamics. Considerations on and results of the vegetation monitoring concept are documented in this paper. In a habitat rich ecosystem like a floodplain different habitats (alluvial forest, semi-aquatic/aquatic sites have different demands on the sampling methods. Therefore, different monitoring designs (preferential, random, systematic, stratified random and transect sampling are discussed and tested for their use in different habitat types of the floodplain. A stratified random sampling is chosen for the alluvial forest stands, as it guarantees an equal distribution of the monitoring plots along the main driving factors, i.e. influence of water. The parameters distance to barrage, ecological flooding, height above thalweg and distance to the new floodplain river are used for stratifying and the plots are placed randomly into these strata, resulting in 117 permanent plots. Due to small changes at the semi-aquatic/aquatic sites a transect sampling was chosen. Further, a rough stratification (channel bed, river bank adjacent floodplain was implemented, which was only possible after the start of the restoration project. To capture the small-scale changes due to the restoration measures on the vegetation, 99 additional plots completed the transect sampling. We conclude that hetereogenous study areas need different monitoring approaches, but, later on, a joint analysis must be possible.

  20. [Variation trends of natural vegetation net primary productivity in China under climate change scenario].

    Science.gov (United States)

    Zhao, Dong-sheng; Wu, Shao-hong; Yin, Yun-he

    2011-04-01

    Based on the widely used Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ) for climate change study, and according to the features of natural environment in China, the operation mechanism of the model was adjusted, and the parameters were modified. With the modified LPJ model and taking 1961-1990 as baseline period, the responses of natural vegetation net primary productivity (NPP) in China to climate change in 1991-2080 were simulated under the Special Report on Emissions Scenarios (SRES) B2 scenario. In 1961-1990, the total NPP of natural vegetation in China was about 3.06 Pg C a(-1); in 1961-2080, the total NPP showed a fluctuant decreasing trend, with an accelerated decreasing rate. Under the condition of slight precipitation change, the increase of mean air temperature would have definite adverse impact on the NPP. Spatially, the NPP decreased from southeast coast to northwest inland, and this pattern would have less variation under climate change. In eastern China with higher NPP, especially in Northeast China, east of North China, and Loess Plateau, the NPP would mainly have a decreasing trend; while in western China with lower NPP, especially in the Tibetan Plateau and Tarim Basin, the NPP would be increased. With the intensive climate change, such a variation trend of NPP would be more obvious.

  1. Verification of“Trend-Volatility Model”in Short-Term Forecast of Grain Production Potential

    Directory of Open Access Journals (Sweden)

    MI Chang-hong

    2016-02-01

    Full Text Available The "trend-volatility model" in short-term forecasting of grain production potential was verified and discussed systematically by using the grain production data from 1949 to 2014, in 16 typical counties and 6 typical districts, and 31 provinces, of China. The results showed as follows:(1 Size of forecast error reflected the precision of short-term production potential, the main reason of large prediction error was a great amount of high yield farmlands were occupied in developed areas and a great increase of vegetable and fruit planted that made grain yield decreased in a short time;(2 The micro-trend amendment method was a necessary part of "trend-volatility model", which could involve the short-term factors such as meteorological factors, science and technology input, social factors and other effects, while macro-trend prediction could not. Therefore, The micro-trend amendment method could improve the forecast precision.(3 In terms of actual situation in recent years in China, the more developed the areas was, the bigger the volatility of short-term production potential was; For the short-term production potential, the stage of increasing-decreasing-recovering also existed in developed areas;(4 In the terms of forecast precision of short-terms production potential, the scale of national was higher than the scale of province, the scale of province was higher than the scale of district, the scale of district was higher than the scale of county. And it was large differences in precision between different provinces, different districts and different counties respectively, which was concerned to the complementarity of domestic climate and the ability of the farmland resistance to natural disasters.

  2. Long-term trends in the total electron content (TEC)

    Science.gov (United States)

    Laštovička, Jan

    2017-04-01

    The long-term trends in the total electron content (TEC) have very little been studied. Lean et al. (2011; J. Geophys. Res., 116, A00H04, doi:10.1029/2010JA016378) studied trends in TEC globally based on JPL maps for 1995-2010. However, their trends appear to be too positive, which is not plausible taking into account the trends in other ionospheric parameters. Therefore they prefer the less positive trends calculated under the assumption of the same level of solar activity in solar cycle minima 22/23 and 23/24. However, as it is now clear, this is not a correct assumption. Lastovicka (2013; J. Geophys. Res. Space Phys., 118, 3831-3835, doi:10.1002/jgra.50261) selected a region around Florence, Italy, as a region with available historical TEC data based on Faraday rotation measurements and remarkably larger than average trends in TEC by Lean et al. (2011). Historical data from Florence provide no trend in TEC. However, foF2 from Juliusruh provide slight negative trends for 1976-1996 but no trends for 1995-2010. Thus the question of reality of trends by Lean et al. (2011) remained open. Here we use TEC from GIM and JPL data for two European regions with high Lean's trends, regions around Florence and around Prague, using 10-14 LT medians, 1998-2015, yearly average values. A classical approach is applied. First a model of solar activity dependence of TEC is constructed separately for each region from all data. Then model data are subtracted from experimental data and analysis is made with residuals. This analysis shows that early data (1998-2001) are by several TECU lower than they should be according to solar activity, the year 2002 is intermediate and in 2003-2015 the data fit well a weak or rather no trend of TEC. The change in TEC data does not seem to be jump-like, it lasted at least a year, if not longer. Thus the positive TEC trends reported by Lean et al. (2011) appear to be affected by data problem; real trends are evidently less positive if any.

  3. Short-term trends in the gas industry - Panorama 2008

    International Nuclear Information System (INIS)

    2008-01-01

    In a context of high investment costs and rising energy prices, and recurring unseasonably warm temperatures in recent years, the growth of natural gas demand is slowing. On the supply side, and on the demand side too, new trends are emerging, with potentially powerful impact on the short-and long-term development of the industry

  4. Gender-Based Violence in India: Long-Term Trends

    Science.gov (United States)

    Simister, John; Mehta, Parnika S.

    2010-01-01

    This article examines long-term trends in Indian society regarding domestic violence between husband and wife, and attitudes to such violence. This article analyzes crime data and uses data from several Indian household surveys: "Work Attitudes and Spending" surveys (1992 to 2007); "World Values Survey" (1990, 1995, 2001, and…

  5. Global Trends in Seasonality of Normalized Difference Vegetation Index (NDVI, 1982–2011

    Directory of Open Access Journals (Sweden)

    Assaf Anyamba

    2013-09-01

    Full Text Available A 30-year series of global monthly Normalized Difference Vegetation Index (NDVI imagery derived from the Global Inventory Modeling and Mapping Studies (GIMMS NDVI3g archive was analyzed for the presence of trends in changing seasonality. Using the Seasonal Trend Analysis (STA procedure, over half (56.30% of land surfaces were found to exhibit significant trends. Almost half (46.10% of the significant trends belonged to three classes of seasonal trends (or changes. Class 1 consisted of areas that experienced a uniform increase in NDVI throughout the year, and was primarily associated with forested areas, particularly broadleaf forests. Class 2 consisted of areas experiencing an increase in the amplitude of the annual seasonal signal whereby increases in NDVI in the green season were balanced by decreases in the brown season. These areas were found primarily in grassland and shrubland regions. Class 3 was found primarily in the Taiga and Tundra biomes and exhibited increases in the annual summer peak in NDVI. While no single attribution of cause could be determined for each of these classes, it was evident that they are primarily found in natural areas (as opposed to anthropogenic land cover conversions and that they are consistent with climate-related ameliorations of growing conditions during the study period.

  6. Long-term change analysis of satellite-based evapotranspiration over Indian vegetated surface

    Science.gov (United States)

    Gupta, Shweta; Bhattacharya, Bimal K.; Krishna, Akhouri P.

    2016-05-01

    In the present study, trend of satellite based annual evapotranspiration (ET) and natural forcing factors responsible for this were analyzed. Thirty years (1981-2010) of ET data at 0.08° grid resolution, generated over Indian region from opticalthermal observations from NOAA PAL and MODIS AQUA satellites, were used. Long-term data on gridded (0.5° x 0.5°) annual rainfall (RF), annual mean surface soil moisture (SSM) ERS scatterometer at 25 km resolution and annual mean incoming shortwave radiation from MERRA-2D reanalysis were also analyzed. Mann-Kendall tests were performed with time series data for trend analysis. Mean annual ET loss from Indian ago-ecosystem was found to be almost double (1100 Cubic Km) than Indian forest ecosystem (550 Cubic Km). Rainfed vegetation systems such as forest, rainfed cropland, grassland showed declining ET trend @ - 4.8, -0.6 &-0.4 Cubic Kmyr-1, respectively during 30 years. Irrigated cropland initially showed ET decline upto 1995 @ -0.8 cubic Kmyr-1 which could possibly be due to solar dimming followed by increasing ET @ 0.9 cubic Kmyr-1 after 1995. A cross-over point was detected between forest ET decline and ET increase in irrigated cropland during 2008. During 2001-2010, the four agriculturally important Indian states eastern, central, western and southern showed significantly increasing ET trend with S-score of 15-25 and Z-score of 1.09-2.9. Increasing ET in western and southern states was found to be coupled with increase in annual rainfall and SSM. But in eastern and central states no significant trend in rainfall was observed though significant increase in ET was noticed. The study recommended to investigate the influence of anthropogenic factors such as increase in area under irrigation, increased use of water for irrigation through ground water pumping, change in cropping pattern and cultivars on increasing ET.

  7. Cohort Measures of Internal Migration: Understanding Long-Term Trends.

    Science.gov (United States)

    Bernard, Aude

    2017-12-01

    Internal migration intensities fluctuate over time, but both migration levels and trends show great diversity. The dynamics underpinning these trends remain poorly understood because they are analyzed almost exclusively by applying period measures to cross-sectional data. This article proposes 10 cohort measures that can be applied to both prospective and retrospective data to systematically examine long-term trends. To demonstrate their benefits, the proposed measures are applied to retrospective survey data for England that provide residential histories from birth to age 50 for cohorts born between 1918 and 1957. The analysis reveals stable lifetime migration for men but increased lifetime migration for women associated with earlier ages at moving in adulthood and a compression of intervals between consecutive moves. The proposed cohort measures provide a more comprehensive picture of migration behavior and should be used to complement period measures in exploring long-term trends. Increasing availability of retrospective and longitudinal survey data means that researchers can now apply the proposed measures to a wide range of countries.

  8. PFLOTRAN-RepoTREND Source Term Comparison Summary.

    Energy Technology Data Exchange (ETDEWEB)

    Frederick, Jennifer M

    2018-03-01

    Code inter-comparison studies are useful exercises to verify and benchmark independently developed software to ensure proper function, especially when the software is used to model high-consequence systems which cannot be physically tested in a fully representative environment. This summary describes the results of the first portion of the code inter-comparison between PFLOTRAN and RepoTREND, which compares the radionuclide source term used in a typical performance assessment.

  9. Long-term trends in the total electron content

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Urbář, Jaroslav; Kozubek, Michal

    2017-01-01

    Roč. 44, č. 16 (2017), s. 8186-8172 ISSN 0094-8276 R&D Projects: GA ČR(CZ) GA15-03909S Institutional support: RVO:68378289 Keywords : total electron content * long-term trend * solar control Subject RIV: DG - Athmosphere Sciences, Meteorology OBOR OECD: Climatic research Impact factor: 4.253, year: 2016 http://onlinelibrary.wiley.com/doi/10.1002/2017GL075063/full

  10. Panorama 2016 - Short-term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, Armelle

    2015-12-01

    In an environment marked by slowing economic growth in emerging markets and developing countries, trends in gas market fundamentals varied widely across the regions during 2015. Structural economic factors stifled growth in natural gas demand, which was unable to take up all the excess supply, leading to imbalance in the global gas market and price weakness which is expected to continue in the short and medium-term. (author)

  11. [Variation trends of the vegetations in distribution region of Amur tiger based on MODIS NDVI].

    Science.gov (United States)

    Wang, Hua-Ru; Wang, Tian-Ming; Ge, Han-Ping

    2012-10-01

    By using the averaged 250 m MODIS NDVI data in growth seasons of 2000-2010 and the approach of ordinary linear regression, this paper analyzed the variation trends of the vegetations in the distribution region of Amur tiger (Panthera tigris altaica), the Far East region of Russia and the eastern part of Northeast China, as well as the relationships between these variation trends and the anthropogenic activities. In 2000 - 2010, the areas with significantly decreased NDVI were sparsely distributed and accounted for 9.6% of the total, while the areas with significantly increased NDVI were mainly concentrated in the central part of northern Russia Far East Region and only accounted for 0.5% of the total. The percentage of the areas with significantly decreased NDVI in the distribution region of Amur tiger was slightly higher than that in the whole study region. The areas with significantly decreased NDVI were mainly distributed in the places of low elevation, gentle slope, and close to roads/railroads. The number of the pixels with significantly decreased NDVI increased with the increase of the nearest distance to residential locations first, and then decreased gradually. The significant decrease of the NDVI was closely related to the anthropogenic activities, and thus, to adopt effective measures to reduce human disturbances could control the vegetation degradation, and further, provide sustainable basis for the protection of Amur tiger and the conservation of the biodiversity in the studied region.

  12. Long-term trends in restoration and associated land treatments in the southwestern United States

    Science.gov (United States)

    Copeland, Stella M.; Munson, Seth M.; Pilliod, David S.; Welty, Justin L.; Bradford, John B.; Butterfield, Bradley J.

    2018-01-01

    Restoration treatments, such as revegetation with seeding or invasive species removal, have been applied on U.S. public lands for decades. Temporal trends in these management actions have not been extensively summarized previously, particularly in the southwestern United States where invasive plant species, drought, and fire have altered dryland ecosystems. We assessed long-term (1940–2010) trends in restoration using approximately 4,000 vegetation treatments conducted on Bureau of Land Management lands across the southwestern United States. We found that since 1940, the proportions of seeding and vegetation/soil manipulation (e.g. vegetation removal or plowing) treatments have declined, while the proportions of prescribed burn and invasive species treatments have increased. Treatments in pinyon-juniper and big sagebrush communities declined in comparison to treatments in desert scrub, creosote bush, and riparian woodland communities. Restoration-focused treatment objectives increased relative to resource extraction objectives. Species richness and proportion of native species used in seeding treatments also increased. Inflation-adjusted costs per area rose 750% for vegetation/soil manipulation, 600% for seeding, and 400% for prescribed burn treatments in the decades from 1981 to 2010. Seeding treatments were implemented in warmer and drier years when compared to the climate conditions of the entire study period and warmer and wetter years relative to several years before and after the treatment. These results suggest that treatments over a 70-year period on public lands in the southwestern United States are shifting toward restoration practices that are increasingly large, expensive, and related to fire and invasive species control.

  13. 20 year long term air quality trends in Israel

    Science.gov (United States)

    Luria, M.

    2017-12-01

    The Israeli air monitoring network was established in the mid 1990's with dozens of measuring sites near most populated areas. During these past 20 years the Israel economy has increased significantly. The population grew by 30%, energy consumption and power generation by more than 40% and the number of motor vehicles increased by nearly 50%. Most of the fossil energy is consumed by the electric power industry that has changed immensely during this period. Until the early 2000's the vast majority of the electricity was generated from coal and heavy oil. However, during the last ten years natural gas has gradually becomes the major source for power generation and for most of the heavy industry. In the present study we examined the impact of these economic trends on the major criteria air pollution parameters; O3, NOx, SO2 and PM10. The analyses was based on the long term trend of median value (50th percentile) and the 90th percentile. The results revealed that SO2 levels throughout the country decreased to very low levels, with the 90th percentile near the detection limit. The levels of PM10, that are relatively high compare with other global regions, did not show any trend during the 20 year period. This is consistent with the fact that most particulate matter results from long range transport of dust from the surrounding deserts. The long term trend of NOx indicates a gradual and steady increase at most measuring sites, which is consistent with the increase of fossil fuel consumption. The increase in NOx levels is most likely the cause for the significant increase in O3 levels found at most sites in a few of them to levels that are considered as an environmental hazard.

  14. Causes of spring vegetation growth trends in the northern mid–high latitudes from 1982 to 2004

    International Nuclear Information System (INIS)

    Mao Jiafu; Shi Xiaoying; Thornton, Peter E; Piao Shilong; Wang Xuhui

    2012-01-01

    The Community Land Model version 4 (CLM4) is applied to explore the spatial–temporal patterns of spring (April–May) vegetation growth trends over the northern mid–high latitudes (NMH) (>25°N) between 1982 and 2004. During the spring season through the 23 yr period, both the satellite-derived and simulated normalized difference vegetation index (NDVI) anomalies show a statistically significant correlation and an overall greening trend within the study area. Consistently with the observed NDVI–temperature relation, the CLM4 NDVI shows a significant positive association with the spring temperature anomaly for the NMH, North America and Eurasia. Large study areas experience temperature discontinuity associated with contrasting NDVI trends. Before and after the turning point (TP) of the temperature trends, climatic variability plays a dominant role, while the other environmental factors exert minor effects on the NDVI tendencies. Simulated vegetation growth is broadly stimulated by the increasing atmospheric CO 2 . Trends show that nitrogen deposition increases NDVI mostly in southeastern China, and decreases NDVI mainly in western Russia after the temperature TP. Furthermore, land use-induced NDVI trends vary roughly with the respective changes in land management practices (crop areas and forest coverage). Our results highlight how non-climatic factors mitigate or exacerbate the impact of temperature on spring vegetation growth, particularly across regions with intensive human activity. (letter)

  15. Causes of spring vegetation greenness trends in the northern mid-high latitudes from 1982 to 2004

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Jiafu [ORNL; Shi, Xiaoying [ORNL; Thornton, Peter E [ORNL; Shilong, Dr. Piao [Peking University; Xuhui, Dr. Wang [Peking University

    2012-01-01

    The Community Land Model version 4 (CLM4) is applied to explore the spatial temporal patterns of spring (April May) vegetation growth trends over the northern mid high latitudes (NMH) (>25 N) between 1982 and 2004. During the spring season through the 23 yr period, both the satellite-derived and simulated normalized difference vegetation index (NDVI) anomalies show a statistically significant correlation and an overall greening trend within the study area. Consistently with the observed NDVI temperature relation, the CLM4 NDVI shows a significant positive association with the spring temperature anomaly for the NMH, North America and Eurasia. Large study areas experience temperature discontinuity associated with contrasting NDVI trends. Before and after the turning point (TP) of the temperature trends, climatic variability plays a dominant role, while the other environmental factors exert minor effects on the NDVI tendencies. Simulated vegetation growth is broadly stimulated by the increasing atmospheric CO2. Trends show that nitrogen deposition increases NDVI mostly in southeastern China, and decreases NDVI mainly in western Russia after the temperature TP. Furthermore, land use-induced NDVI trends vary roughly with the respective changes in land management practices (crop areas and forest coverage). Our results highlight how non-climatic factors mitigate or exacerbate the impact of temperature on spring vegetation growth, particularly across regions with intensive human activity.

  16. Detecting long-term changes to vegetation in northern Canada using the Landsat satellite image archive

    International Nuclear Information System (INIS)

    Fraser, R H; Olthof, I; Carrière, M; Deschamps, A; Pouliot, D

    2011-01-01

    Analysis of coarse resolution (∼1 km) satellite imagery has provided evidence of vegetation changes in arctic regions since the mid-1980s that may be attributable to climate warming. Here we investigate finer-scale changes to northern vegetation over the same period using stacks of 30 m resolution Landsat TM and ETM + satellite images. Linear trends in the normalized difference vegetation index (NDVI) and tasseled cap indices are derived for four widely spaced national parks in northern Canada. The trends are related to predicted changes in fractional shrub and other vegetation covers using regression tree classifiers trained with plot measurements and high resolution imagery. We find a consistent pattern of greening (6.1–25.5% of areas increasing) and predicted increases in vascular vegetation in all four parks that is associated with positive temperature trends. Coarse resolution (3 km) NDVI trends were not detected in two of the parks that had less intense greening. A range of independent studies and observations corroborate many of the major changes observed.

  17. Tundra landform and vegetation productivity trend maps for the Arctic Coastal Plain of northern Alaska

    Science.gov (United States)

    Lara, Mark J.; Nitze, Ingmar; Grosse, Guido; McGuire, A. David

    2018-01-01

    Arctic tundra landscapes are composed of a complex mosaic of patterned ground features, varying in soil moisture, vegetation composition, and surface hydrology over small spatial scales (10–100 m). The importance of microtopography and associated geomorphic landforms in influencing ecosystem structure and function is well founded, however, spatial data products describing local to regional scale distribution of patterned ground or polygonal tundra geomorphology are largely unavailable. Thus, our understanding of local impacts on regional scale processes (e.g., carbon dynamics) may be limited. We produced two key spatiotemporal datasets spanning the Arctic Coastal Plain of northern Alaska (~60,000 km2) to evaluate climate-geomorphological controls on arctic tundra productivity change, using (1) a novel 30 m classification of polygonal tundra geomorphology and (2) decadal-trends in surface greenness using the Landsat archive (1999–2014). These datasets can be easily integrated and adapted in an array of local to regional applications such as (1) upscaling plot-level measurements (e.g., carbon/energy fluxes), (2) mapping of soils, vegetation, or permafrost, and/or (3) initializing ecosystem biogeochemistry, hydrology, and/or habitat modeling.

  18. Multiscale Trend Analysis for Pampa Grasslands Using Ground Data and Vegetation Sensor Imagery

    Directory of Open Access Journals (Sweden)

    Fernando C. Scottá

    2015-07-01

    Full Text Available This study aimed to evaluate changes in the aboveground net primary productivity (ANPP of grasslands in the Pampa biome by using experimental plots and changes in the spectral responses of similar vegetation communities obtained by remote sensing and to compare both datasets with meteorological variations to validate the transition scales of the datasets. Two different geographic scales were considered in this study. At the local scale, an analysis of the climate and its direct influences on grassland ANPP was performed using data from a long-term experiment. At the regional scale, the influences of climate on the grassland reflectance patterns were determined using vegetation sensor imagery data. Overall, the monthly variations of vegetation canopy growth analysed using environmental changes (air temperature, total rainfall and total evapotranspiration were similar. The results from the ANPP data and the NDVI data showed the that variations in grassland growth were similar and independent of the analysis scale, which indicated that local data and the relationships of local data with climate can be considered at the regional scale in the Pampa biome by using remote sensing.

  19. Local Vegetation Trends in the Sahel of Mali and Senegal Using Long Time Series FAPAR Satellite Products and Field Measurement (1982–2010

    Directory of Open Access Journals (Sweden)

    Martin Brandt

    2014-03-01

    Full Text Available Local vegetation trends in the Sahel of Mali and Senegal from Geoland Version 1 (GEOV1 (5 km and the third generation Global Inventory Modeling and Mapping Studies (GIMMS3g (8 km Fraction of Absorbed Photosynthetically Active Radiation (FAPAR time series are studied over 29 years. For validation and interpretation of observed greenness trends, two methods are applied: (1 a qualitative approach using in-depth knowledge of the study areas and (2 a quantitative approach by time series of biomass observations and rainfall data. Significant greening trends from 1982 to 2010 are consistently observed in both GEOV1 and GIMMS3g FAPAR datasets. Annual rainfall increased significantly during the observed time period, explaining large parts of FAPAR variations at a regional scale. Locally, GEOV1 data reveals a heterogeneous pattern of vegetation change, which is confirmed by long-term ground data and site visits. The spatial variability in the observed vegetation trends in the Sahel area are mainly caused by varying tree- and land-cover, which are controlled by human impact, soil and drought resilience. A large proportion of the positive trends are caused by the increment in leaf biomass of woody species that has almost doubled since the 1980s due to a tree cover regeneration after a dry-period. This confirms the re-greening of the Sahel, however, degradation is also present and sometimes obscured by greening. GEOV1 as compared to GIMMS3g made it possible to better characterize the spatial pattern of trends and identify the degraded areas in the study region.

  20. [Trends of vegetables and fruits consumption among Chinese adults aged 18 to 44 years old from 1991 to 2011].

    Science.gov (United States)

    Xiao, Yingting; Su, Chang; Ouyang, Yifei; Zhang, Bing

    2015-03-01

    To identify the trends of vegetables and fruits consumption among Chinese adults aged 18 to 44 years old from 1991 to 2011. Twenty four hour dietary recall data from China Health and Nutrition Survey (1991, 1993, 1997, 2000, 2004, 2006, 2009 and 2011) were used to identify the trends of vegetables and fruits consumption among Chinese between 18 and 44 years old. From 1991 to 2011, the proportion of daily consumption of vegetables rarely varied, while the vegetables intake declined significantly; and the proportion of daily consumption and intake of fruits kept increasing as follows. By 2011, the proportion of daily consumption and intake of vegetables and fruits among the respondents were 99.7%, 48.0%, 321.6 g/d, and 90.1 g/d respectively. A significant drop was found in the vegetables intake among the respondents against the vegetables intake as recommended by the Chinese dietary guidelines, up to 50.2% in 2011; a significant rise was found in the fruits intake of the respondents against the fruits intake as recommended by the said guidelines, up to 17.4% in 2011. The average daily intake of vegetables and fruits of young and middle-aged residents (18-44 age group) in nine provinces in China was found lower than that recommended in the Chinese dietary guidelines; in view of the high proportion of people having less vegetables and fruits intake that those recommended by the Chinese dietary guidelines, further measures are expected to encourage their vegetables and fruits intake.

  1. Long term precipitation trends and variability within the Mediterranean region

    Directory of Open Access Journals (Sweden)

    C. M. Philandras

    2011-12-01

    Full Text Available In this study, the trends and variability of annual precipitation totals and annual rain days over land within the Mediterranean region are analyzed. Long term ground-based observations concerning, on one hand, monthly precipitation totals (1900–2010 and rain days (1965–2010 from 40 meteorological stations within the Mediterranean region were obtained from the Hellenic National Meteorological Service and the World Climate Data and Monitoring Programme (WCDMP of the World Meteorological Organization. On the other hand, high spatial resolution (0.5° × 0.5° gridded monthly data CRU TS 3.1 were acquired from the Climatic Research Unit, University of East Anglia, for the period 1901–2009. The two datasets were compared by means of trends and variability, while the influence of the North Atlantic Oscillation (NAO in the Mediterranean precipitation was examined. In the process, the climatic changes in the precipitation regime between the period 1961–1990 (reference period and the period 2071–2100 (future climate were presented using climate model simulations (RACMO2.1/KNMI. The future climate projections were based on SRES A1B.

    The findings of the analysis showed that statistically significant (95% confidence level negative trends of the annual precipitation totals exist in the majority of Mediterranean regions during the period 1901–2009, with an exception of northern Africa, southern Italy and western Iberian peninsula, where slight positive trends (not statistically significant at 95% CL appear. Concerning the annual number of rain days, a pronounced decrease of 20 %, statistically significant (95% confidence level, appears in representative meteorological stations of east Mediterranean, while the trends are insignificant for west and central Mediterranean. Additionally, NAO index was found to be anticorrelated with the precipitation totals and the number of rain days mainly in Spain, southern France, Italy and Greece. These

  2. LONG-TERM TRENDS IN THE SOLAR WIND PROTON MEASUREMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Heather A.; McComas, David J. [Southwest Research Institute, San Antonio, TX (United States); DeForest, Craig E. [Southwest Research Institute, Boulder, CO (United States)

    2016-11-20

    We examine the long-term time evolution (1965–2015) of the relationships between solar wind proton temperature ( T {sub p}) and speed ( V {sub p}) and between the proton density ( n {sub p}) and speed using OMNI solar wind observations taken near Earth. We find a long-term decrease in the proton temperature–speed ( T {sub p}– V {sub p}) slope that lasted from 1972 to 2010, but has been trending upward since 2010. Since the solar wind proton density–speed ( n {sub p}– V {sub p}) relationship is not linear like the T {sub p}– V {sub p} relationship, we perform power-law fits for n {sub p}– V {sub p}. The exponent (steepness in the n {sub p}– V {sub p} relationship) is correlated with the solar cycle. This exponent has a stronger correlation with current sheet tilt angle than with sunspot number because the sunspot number maxima vary considerably from cycle to cycle and the tilt angle maxima do not. To understand this finding, we examined the average n {sub p} for different speed ranges, and found that for the slow wind n {sub p} is highly correlated with the sunspot number, with a lag of approximately four years. The fast wind n {sub p} variation was less, but in phase with the cycle. This phase difference may contribute to the n {sub p}– V {sub p} exponent correlation with the solar cycle. These long-term trends are important since empirical formulas based on fits to T {sub p} and V {sub p} data are commonly used to identify interplanetary coronal mass ejections, but these formulas do not include any time dependence. Changes in the solar wind density over a solar cycle will create corresponding changes in the near-Earth space environment and the overall extent of the heliosphere.

  3. Evaluating temporal consistency of long-term global NDVI datasets for trend analysis

    DEFF Research Database (Denmark)

    Tian, Feng; Fensholt, Rasmus; Verbesselt, Jan

    2015-01-01

    -sensor NDVI time series by analyzing the co-occurrence between breaks in the NDVI time series and sensor shifts from GIMMS3g (Global Inventory Modeling and Mapping Studies 3rd generation), VIP3 (Vegetation Index and Phenology version 3), LTDR4 (Long Term Data Record version 4) and SPOT-VGT (Système Pour l......, potentially introducing uncertainties in NDVI trend analysis. Platform/sensor change from VGT-1 to VGT-2 is found to cause a significant positive break in the SPOT-VGT NDVI time series. Potential artifacts exist in humid, dry-subhumid, semi-arid and hyper-arid regions of GIMMS3g NDVI, whereas no signs...

  4. High-latitude tree growth and satellite vegetation indices: Correlations and trends in Russia and Canada (1982-2008)

    Science.gov (United States)

    Berner, Logan T.; Beck, Pieter S. A.; Bunn, Andrew G.; Lloyd, Andrea H.; Goetz, Scott J.

    2011-03-01

    Vegetation in northern high latitudes affects regional and global climate through energy partitioning and carbon storage. Spaceborne observations of vegetation, largely based on the normalized difference vegetation index (NDVI), suggest decreased productivity during recent decades in many regions of the Eurasian and North American boreal forests. To improve interpretation of NDVI trends over forest regions, we examined the relationship between NDVI from the advanced very high resolution radiometers and tree ring width measurements, a proxy of tree productivity. We collected tree core samples from spruce, pine, and larch at 22 sites in northeast Russia and northwest Canada. Annual growth rings were measured and used to generate site-level ring width index (RWI) chronologies. Correlation analysis was used to assess the association between RWI and summer NDVI from 1982 to 2008, while linear regression was used to examine trends in both measurements. The correlation between NDVI and RWI was highly variable across sites, though consistently positive (r = 0.43, SD = 0.19, n = 27). We observed significant temporal autocorrelation in both NDVI and RWI measurements at sites with evergreen conifers (spruce and pine), though weak autocorrelation at sites with deciduous conifers (larch). No sites exhibited a positive trend in both NDVI and RWI, although five sites showed negative trends in both measurements. While there are technological and physiological limitations to this approach, these findings demonstrate a positive association between NDVI and tree ring measurements, as well as the importance of considering lagged effects when modeling vegetation productivity using satellite data.

  5. Breaks in MODIS time series portend vegetation change: verification using long-term data in an arid grassland ecosystem.

    Science.gov (United States)

    Browning, Dawn M; Maynard, Jonathan J; Karl, Jason W; Peters, Debra C

    2017-07-01

    Frequency and severity of extreme climatic events are forecast to increase in the 21st century. Predicting how managed ecosystems may respond to climatic extremes is intensified by uncertainty associated with knowing when, where, and how long effects of extreme events will be manifest in an ecosystem. In water-limited ecosystems with high inter-annual variability in rainfall, it is important to be able to distinguish responses that result from seasonal fluctuations in rainfall from long-term directional increases or decreases in precipitation. A tool that successfully distinguishes seasonal from directional biomass responses would allow land managers to make informed decisions about prioritizing mitigation strategies, allocating human resource monitoring efforts, and mobilizing resources to withstand extreme climatic events. We leveraged long-term observations (2000-2013) of quadrat-level plant biomass at multiple locations across a semiarid landscape in southern New Mexico to verify the use of Normalized Difference Vegetation Index (NDVI) time series derived from 250-m Moderate Resolution Imaging Spectroradiometer (MODIS) data as a proxy for changes in aboveground productivity. This period encompassed years of sustained drought (2000-2003) and record-breaking high rainfall (2006 and 2008) followed by subsequent drought years (2011 through 2013) that resulted in a restructuring of plant community composition in some locations. Our objective was to decompose vegetation patterns derived from MODIS NDVI over this period into contributions from (1) the long-term trend, (2) seasonal cycle, and (3) unexplained variance using the Breaks for Additive Season and Trend (BFAST) model. BFAST breakpoints in NDVI trend and seasonal components were verified with field-estimated biomass at 15 sites that differed in species richness, vegetation cover, and soil properties. We found that 34 of 45 breaks in NDVI trend reflected large changes in mean biomass and 16 of 19 seasonal

  6. CLIMATE CHANGE: LONG-TERM TRENDS AND SHORT-TERM OSCILLATIONS

    Institute of Scientific and Technical Information of China (English)

    GAO Xin-quan; ZHANG Xin; QIAN Wei-hong

    2006-01-01

    Identifying the Northern Hemisphere (NH) temperature reconstruction and instrumental data for the past 1000 years shows that climate change in the last millennium includes long-term trends and various oscillations. Two long-term trends and the quasi-70-year oscillation were detected in the global temperature series for the last 140 years and the NH millennium series. One important feature was emphasized that temperature decreases slowly but it increases rapidly based on the analysis of different series. Benefits can be obtained of climate change from understanding various long-term trends and oscillations. Millennial temperature proxies from the natural climate system and time series of nonlinear model system are used in understanding the natural climate change and recognizing potential benefits by using the method of wavelet transform analysis. The results from numerical modeling show that major oscillations contained in numerical solutions on the interdecadal timescale are consistent with that of natural proxies. It seems that these oscillations in the climate change are not directly linked with the solar radiation as an external forcing. This investigation may conclude that the climate variability at the interdecadal timescale strongly depends on the internal nonlinear effects in the climate system.

  7. Soil and vegetation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.

    1995-06-01

    Soil sampling and analysis evaluates long-term contamination trends and monitors environmental radionuclide inventories. This section of the 1994 Hanford Site Environmental Report summarizes the soil and vegetation surveillance programs which were conducted during 1994. Vegetation surveillance is conducted offsite to monitor atmospheric deposition of radioactive materials in areas not under cultivation and onsite at locations adjacent to potential sources of radioactivity.

  8. Long-term trends of surface ozone and its influencing factors at the Mt Waliguan GAW station, China - Part 1: Overall trends and characteristics

    Science.gov (United States)

    Xu, Wanyun; Lin, Weili; Xu, Xiaobin; Tang, Jie; Huang, Jianqing; Wu, Hao; Zhang, Xiaochun

    2016-05-01

    Tropospheric ozone is an important atmospheric oxidant, greenhouse gas and atmospheric pollutant at the same time. The oxidation capacity of the atmosphere, climate, human and vegetation health can be impacted by the increase of the ozone level. Therefore, long-term determination of trends of baseline ozone is highly needed information for environmental and climate change assessment. So far, studies on the long-term trends of ozone at representative sites are mainly available for European and North American sites. Similar studies are lacking for China and many other developing countries. Measurements of surface ozone were carried out at a baseline Global Atmospheric Watch (GAW) station in the north-eastern Tibetan Plateau region (Mt Waliguan, 36°17' N, 100°54' E, 3816 m a.s.l.) for the period of 1994 to 2013. To uncover the variation characteristics, long-term trends and influencing factors of surface ozone at this remote site in western China, a two-part study has been carried out, with this part focusing on the overall characteristics of diurnal, seasonal and long-term variations and the trends of surface ozone. To obtain reliable ozone trends, we performed the Mann-Kendall trend test and the Hilbert-Huang transform (HHT) analysis on the ozone data. Our results confirm that the mountain-valley breeze plays an important role in the diurnal cycle of surface ozone at Waliguan, resulting in higher ozone values during the night and lower ones during the day, as was previously reported. Systematic diurnal and seasonal variations were found in mountain-valley breezes at the site, which were used in defining season-dependent daytime and nighttime periods for trend calculations. Significant positive trends in surface ozone were detected for both daytime (0.24 ± 0.16 ppbv year-1) and nighttime (0.28 ± 0.17 ppbv year-1). The largest nighttime increasing rate occurred in autumn (0.29 ± 0.11 ppbv year-1), followed by spring (0.24 ± 0.12 ppbv year-1), summer (0.22 ± 0

  9. Long-term dynamics of the hemiparasite Rhinanthus angustifolius and its relationship with vegetation structure

    NARCIS (Netherlands)

    Ameloot, Els; Verheyen, Kris; Bakker, Jan P.; De Vries, Yzaak; Hermy, Martin

    2006-01-01

    Questions: 1. How are the long-term dynamics of the root hemiparasite Rhinanthus angustifolius related to vegetation structure, grassland management and climate? 2. Does R. angustifolius have a long-term impact on standing crop and community composition? Location: A formerly fertilized grassland,

  10. Dual scale trend analysis for evaluating climatic and anthropogenic effects on the vegetated land surface in Russia and Kazakhstan

    Energy Technology Data Exchange (ETDEWEB)

    De Beurs, K M [Department of Geography, Virginia Polytechnic Institute and State University, 107 Major Williams Hall, Blacksburg, VA 24061 (United States); Wright, C K; Henebry, G M, E-mail: kdebeurs@vt.ed, E-mail: christopher.wright@sdstate.ed, E-mail: geoffrey.henebry@sdstate.ed [Geographic Information Science Center of Excellence (GIScCE), South Dakota State University, 1021 Medary Avenue, Wecota Hall 506B, Brookings, SD 57007-3510 (United States)

    2009-10-15

    We present a dual scale trend analysis for characterizing and comparing two contrasting areas of change in Russia and Kazakhstan that lie less than 800 km apart. We selected a global NASA MODIS (moderate resolution imaging spectroradiometer) product (MCD43C4 and MCD43A4) at a 0.05 deg. ({approx}5.6 km) and 500 m spatial resolution and a 16-day temporal resolution from 2000 to 2008. We applied a refinement of the seasonal Kendall trend method to the normalized difference vegetation index (NDVI) image series at both scales. We only incorporated composites during the vegetative growing season which was delineated by start of season and end of season estimates based on analysis of normalized difference infrared index data. Trend patterns on two scales pointed to drought as the proximal cause of significant declines in NDVI in Kazakhstan. In contrast, the area of increasing NDVI trend in Russia was linked through the dual scale analysis with agricultural land cover change. The coarser scale analysis was relevant to atmospheric boundary layer processes, while the finer scale data revealed trends that were more relevant to human decision-making and regional economics.

  11. Dual scale trend analysis for evaluating climatic and anthropogenic effects on the vegetated land surface in Russia and Kazakhstan

    International Nuclear Information System (INIS)

    De Beurs, K M; Wright, C K; Henebry, G M

    2009-01-01

    We present a dual scale trend analysis for characterizing and comparing two contrasting areas of change in Russia and Kazakhstan that lie less than 800 km apart. We selected a global NASA MODIS (moderate resolution imaging spectroradiometer) product (MCD43C4 and MCD43A4) at a 0.05 deg. (∼5.6 km) and 500 m spatial resolution and a 16-day temporal resolution from 2000 to 2008. We applied a refinement of the seasonal Kendall trend method to the normalized difference vegetation index (NDVI) image series at both scales. We only incorporated composites during the vegetative growing season which was delineated by start of season and end of season estimates based on analysis of normalized difference infrared index data. Trend patterns on two scales pointed to drought as the proximal cause of significant declines in NDVI in Kazakhstan. In contrast, the area of increasing NDVI trend in Russia was linked through the dual scale analysis with agricultural land cover change. The coarser scale analysis was relevant to atmospheric boundary layer processes, while the finer scale data revealed trends that were more relevant to human decision-making and regional economics.

  12. Evaluating the Long-term Water Cycle Trends at a Global-scale using Satellite and Assimilation Datasets

    Science.gov (United States)

    Kim, H.; Lakshmi, V.

    2017-12-01

    Global-scale soil moisture and rainfall products retrieved from remotely sensed and assimilation datasets provide an effective way to monitor near surface soil moisture content and precipitation with sub-daily temporal resolution. In the present study, we employed the concept of the stored precipitation fraction Fp(f) in order to examine the long-term water cycle trends at a global-scale. The analysis was done for Fp(f) trends with the various geophysical aspects such as climate zone, land use classifications, amount of vegetation, and soil properties. Furthermore, we compared a global-scale Fp(f) using different microwave-based satellite soil moisture datasets. The Fp(f) is calculated by utilized surface soil moisture dataset from Soil Moisture Active Passive (SMAP), Soil Moisture and Ocean Salinity, Advanced Scatterometer, Advanced Microwave Scanning Radiometer 2, and precipitation information from Global Precipitation Measurement Mission and Global Land Data Assimilation System. Different results from microwave-based soil moisture dataset showed discordant results particularly over arid and highly vegetated regions. The results of this study provide us new insights of the long-term water cycle trends over different land surface areas. Thereby also highlighting the advantages of the recently available GPM and SMAP datasets for the uses in various hydrometeorological applications.

  13. Vegetation

    DEFF Research Database (Denmark)

    Epstein, H.E.; Walker, D.A.; Bhatt, U.S.

    2012-01-01

    increased 20-26%. • Increasing shrub growth and range extension throughout the Low Arctic are related to winter and early growing season temperature increases. Growth of other tundra plant types, including graminoids and forbs, is increasing, while growth of mosses and lichens is decreasing. • Increases...... in vegetation (including shrub tundra expansion) and thunderstorm activity, each a result of Arctic warming, have created conditions that favor a more active Arctic fire regime....

  14. 1998 Annual Status Report: Status and Trend of Submersed and Floating-leaved Aquatic Vegetation in Thirty-two Backwaters in Pools 4, 8, 13, and 26 and La Grange Pool of the Upper Mississippi River System

    National Research Council Canada - National Science Library

    Yin, Yao

    2000-01-01

    .... The status and trend of aquatic vegetation in 1998 varied among the thirty-two backwaters. In upper Pool 4 (above Lake Pepin), where aquatic vegetation has declined since 1991, the trend continued in 1998...

  15. Google Trends terms reporting rhinitis and related topics differ in European countries

    DEFF Research Database (Denmark)

    Bousquet, J.; Agache, I; Anto, J M

    2017-01-01

    Google Trends (GT) searches trends of specific queries in Google and reflects the real-life epidemiology of allergic rhinitis. We compared Google Trends terms related to allergy and rhinitis in all European Union countries, Norway and Switzerland from 1 January 2011 to 20 December 2016. The aim w...

  16. Detecting long-term growth trends using tree rings: a critical evaluation of methods.

    Science.gov (United States)

    Peters, Richard L; Groenendijk, Peter; Vlam, Mart; Zuidema, Pieter A

    2015-05-01

    Tree-ring analysis is often used to assess long-term trends in tree growth. A variety of growth-trend detection methods (GDMs) exist to disentangle age/size trends in growth from long-term growth changes. However, these detrending methods strongly differ in approach, with possible implications for their output. Here, we critically evaluate the consistency, sensitivity, reliability and accuracy of four most widely used GDMs: conservative detrending (CD) applies mathematical functions to correct for decreasing ring widths with age; basal area correction (BAC) transforms diameter into basal area growth; regional curve standardization (RCS) detrends individual tree-ring series using average age/size trends; and size class isolation (SCI) calculates growth trends within separate size classes. First, we evaluated whether these GDMs produce consistent results applied to an empirical tree-ring data set of Melia azedarach, a tropical tree species from Thailand. Three GDMs yielded similar results - a growth decline over time - but the widely used CD method did not detect any change. Second, we assessed the sensitivity (probability of correct growth-trend detection), reliability (100% minus probability of detecting false trends) and accuracy (whether the strength of imposed trends is correctly detected) of these GDMs, by applying them to simulated growth trajectories with different imposed trends: no trend, strong trends (-6% and +6% change per decade) and weak trends (-2%, +2%). All methods except CD, showed high sensitivity, reliability and accuracy to detect strong imposed trends. However, these were considerably lower in the weak or no-trend scenarios. BAC showed good sensitivity and accuracy, but low reliability, indicating uncertainty of trend detection using this method. Our study reveals that the choice of GDM influences results of growth-trend studies. We recommend applying multiple methods when analysing trends and encourage performing sensitivity and reliability

  17. Climate-vegetation-soil interactions and long-term hydrologic partitioning: signatures of catchment co-evolution

    Directory of Open Access Journals (Sweden)

    P. A. Troch

    2013-06-01

    Full Text Available Budyko (1974 postulated that long-term catchment water balance is controlled to first order by the available water and energy. This leads to the interesting question of how do landscape characteristics (soils, geology, vegetation and climate properties (precipitation, potential evaporation, number of wet and dry days interact at the catchment scale to produce such a simple and predictable outcome of hydrological partitioning? Here we use a physically-based hydrologic model separately parameterized in 12 US catchments across a climate gradient to decouple the impact of climate and landscape properties to gain insight into the role of climate-vegetation-soil interactions in long-term hydrologic partitioning. The 12 catchment models (with different paramterizations are subjected to the 12 different climate forcings, resulting in 144 10 yr model simulations. The results are analyzed per catchment (one catchment model subjected to 12 climates and per climate (one climate filtered by 12 different model parameterization, and compared to water balance predictions based on Budyko's hypothesis (E/P = ϕ (Ep/P; E: evaporation, P: precipitation, Ep: potential evaporation. We find significant anti-correlation between average deviations of the evaporation index (E/P computed per catchment vs. per climate, compared to that predicted by Budyko. Catchments that on average produce more E/P have developed in climates that on average produce less E/P, when compared to Budyko's prediction. Water and energy seasonality could not explain these observations, confirming previous results reported by Potter et al. (2005. Next, we analyze which model (i.e., landscape filter characteristics explain the catchment's tendency to produce more or less E/P. We find that the time scale that controls subsurface storage release explains the observed trend. This time scale combines several geomorphologic and hydraulic soil properties. Catchments with relatively longer

  18. Long-term trends in alcohol policy attitudes in Norway.

    Science.gov (United States)

    Rossow, Ingeborg; Storvoll, Elisabet E

    2014-05-01

    The aim of this study was to describe trends in attitudes to alcohol control policies in Norway over a period of 50 years and to discuss how these trends relate to developments in alcohol policy. Survey data from 17 national population surveys, national statistics and previous publications were applied to describe trends in attitudes to alcohol control polices (access to alcohol and price) and changes in these policies over the period 1962 to 2012. From 1962 to 1999, an increasing proportion of the population reported that regulations on availability of alcohol were too strict and that alcohol prices were too high, whereas in the 2000s this trend was reversed and support for existing control policies increased. Although the pillars of Norwegian alcohol policy--high prices, restricted access and a state monopoly on retail sales-remained, control policies were gradually relaxed throughout the entire period. Relaxation of strict alcohol control policies in Norway in the first four decades were probably, in part, the result of increasingly liberal public opinion. The subsequent reversed trend in opinions with increasing support for control policies may be due to several factors, for example, consumer-oriented changes in the monopoly system, increased availability and affordability, increased awareness of alcohol-related harm and the effectiveness of control policies. Thus, the dynamics of policies and attitudes may well change over time. © 2013 Australasian Professional Society on Alcohol and other Drugs.

  19. Integrated modeling of long-term vegetation and hydrologic dynamics in Rocky Mountain watersheds

    Science.gov (United States)

    Robert Steven Ahl

    2007-01-01

    Changes in forest structure resulting from natural disturbances, or managed treatments, can have negative and long lasting impacts on water resources. To facilitate integrated management of forest and water resources, a System for Long-Term Integrated Management Modeling (SLIMM) was developed. By combining two spatially explicit, continuous time models, vegetation...

  20. Influence of Vegetation on Long-term Phosphorus Sequestration in Subtropical Treatment Wetlands.

    Science.gov (United States)

    Bhomia, R K; Reddy, K R

    2018-03-01

    Sustainable operation of a treatment wetland depends on its continued treatment of influent water to achieve desired outflow water quality targets. Water treatment or nutrient reduction is attained by a combination of biotic and abiotic processes. We studied one of the world's largest treatment wetlands established to revive the Florida Everglades from impacts of excessive phosphorus (P) inputs. Phosphorus retained in the treatment wetlands is sequestered within the accumulated material via biotic and abiotic pathways that are influenced by the existing wetland vegetation. Recently accreted soils (RAS) provide a major sink for stored P, and long-term P removal efficiency of treatment wetlands is governed by the stability of accreted P because more stable P pools are less susceptible to mobilization and loss. We quantified reactive P (extracted with acid and alkali) and nonreactive P (not extracted with acid and alkali) pools in wetland soils by using an operationally defined P fractionation scheme and assessed the effect of emergent vs. submerged vegetation communities on stability of sequestered P. Reactive P comprised 63 to 79% of total P in wetland soils without a clear difference between two vegetation groups. The quantities of reactive P forms (inorganic vs. organic P) were significantly different between two vegetation types. A higher proportion of reactive P was stored as organic P in flocculent detrital organic matter (floc) and RAS under emergent vegetation (46-47% total P) in comparison with submerged vegetation (21-34% total P). The dominant P removal pathway in the submerged vegetation system was associated with calcium whereas plant uptake and peat burial appeared to be the main pathway in the emergent vegetation system. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. [Effects of a long-term intervention in a work cafeteria on employee vegetable intake].

    Science.gov (United States)

    Misawa, Akemi; Yoshita, Katsushi; Fukumura, Tomoe; Tanaka, Taichiro; Tamaki, Junko; Takebayashi, Toru; Kusaka, Yukinori; Nakagawa, Hideaki; Yamato, Hiroshi; Okayama, Akira; Miura, Katsuyuki; Okamura, Tomonori; Ueshima, Hirotsugu

    2015-01-01

    We examined the effects on employee vegetable intake of a long-term intervention in an employee work cafeteria. The subjects were approximately 1,200 employees (aged 19-61 years) of an industrial company in Fukui prefecture. We promoted the intake of typical Japanese style meals that combined three elements (staple foods, main dishes and vegetable dishes) to increase vegetables intake. We displayed all items on the menus of the employee cafeteria using three colors (yellow, red and green to denote three elements) to indicate healthy food choices for the maintenance of a healthy food environment. We advised employees to choose meals containing the three elements at the time of payment, for nutritional education (appropriate portion choice: APC). We evaluated the ratio of APC at the same time. To calculate the mean daily intake per person, we carried out a questionnaire survey similar to the "semi-quantitative food frequency questionnaire" and asked about the frequency and approximate intake of vegetables. The APC was 63.5% after one year of intervention, significantly increased to 82.1% after two years (p breakfast (p < 0.001), lunch (p < 0.001) and dinner (p = 0.011), and from vegetable juice (p = 0.030) significantly increased after three years of intervention. The consumption of pickles significantly decreased after three years of intervention (p = 0.009). It was estimated that the vegetable intake of men increased from 167.3 to 184.6 g, and that of women from 157.9 to 187.7 g. Employee estimated vegetable intake was significantly increased and that of pickles was significantly decreased by a long-term intervention (three years) in the employee work cafeteria.

  2. Detecting Inter-Annual Variations in the Phenology of Evergreen Conifers Using Long-Term MODIS Vegetation Index Time Series

    OpenAIRE

    Ulsig, Laura; Nichol, Caroline J.; Huemmrich, Karl F.; Landis, David R.; Middleton, Elizabeth M.; Lyapustin, Alexei I.; Mammarella, Ivan; Levula, Janne; Porcar-Castell, Albert

    2017-01-01

    Long-term observations of vegetation phenology can be used to monitor the response of terrestrial ecosystems to climate change. Satellite remote sensing provides the most efficient means to observe phenological events through time series analysis of vegetation indices such as the Normalized Difference Vegetation Index (NDVI). This study investigates the potential of a Photochemical Reflectance Index (PRI), which has been linked to vegetation light use efficiency, to improve the accuracy of MO...

  3. Detecting inter-annual variations in the phenology of evergreen conifers using long-term MODIS vegetation index time series.

    OpenAIRE

    Ulsig, Laura

    2016-01-01

    Long-term observations of vegetation phenology can be used to monitor the response of terrestrial ecosystems to climate change. Satellite remote sensing provides the most efficient means to observe phenological events through time series analysis of vegetation indices such as the Normalised Difference Vegetation Index (NDVI). This study investigates the potential of the Photochemical Reflectance Index (PRI), which has been linked to vegetation light use efficiency, to improve the accuracy of ...

  4. Spring onset variations and long-term trends from new hemispheric-scale products and remote sensing

    Science.gov (United States)

    Dye, D. G.; Li, X.; Ault, T.; Zurita-Milla, R.; Schwartz, M. D.

    2015-12-01

    Spring onset is commonly characterized by plant phenophase changes among a variety of biophysical transitions and has important implications for natural and man-managed ecosystems. Here, we present a new integrated analysis of variability in gridded Northern Hemisphere spring onset metrics. We developed a set of hemispheric temperature-based spring indices spanning 1920-2013. As these were derived solely from meteorological data, they are used as a benchmark for isolating the climate system's role in modulating spring "green up" estimated from the annual cycle of normalized difference vegetation index (NDVI). Spatial patterns of interannual variations, teleconnections, and long-term trends were also analyzed in all metrics. At mid-to-high latitudes, all indices exhibit larger variability at interannual to decadal time scales than at spatial scales of a few kilometers. Trends of spring onset vary across space and time. However, compared to long-term trend, interannual to decadal variability generally accounts for a larger portion of the total variance in spring onset timing. Therefore, spring onset trends identified from short existing records may be aliased by decadal climate variations due to their limited temporal depth, even when these records span the entire satellite era. Based on our findings, we also demonstrated that our indices have skill in representing ecosystem-level spring phenology and may have important implications in understanding relationships between phenology, atmosphere dynamics and climate variability.

  5. Multiple long-term trends and trend reversals dominate environmental conditions in a man-made freshwater reservoir.

    Science.gov (United States)

    Znachor, Petr; Nedoma, Jiří; Hejzlar, Josef; Seďa, Jaromír; Kopáček, Jiří; Boukal, David; Mrkvička, Tomáš

    2018-05-15

    Man-made reservoirs are common across the world and provide a wide range of ecological services. Environmental conditions in riverine reservoirs are affected by the changing climate, catchment-wide processes and manipulations with the water level, and water abstraction from the reservoir. Long-term trends of environmental conditions in reservoirs thus reflect a wider range of drivers in comparison to lakes, which makes the understanding of reservoir dynamics more challenging. We analysed a 32-year time series of 36 environmental variables characterising weather, land use in the catchment, reservoir hydrochemistry, hydrology and light availability in the small, canyon-shaped Římov Reservoir in the Czech Republic to detect underlying trends, trend reversals and regime shifts. To do so, we fitted linear and piecewise linear regression and a regime shift model to the time series of mean annual values of each variable and to principal components produced by Principal Component Analysis. Models were weighted and ranked using Akaike information criterion and the model selection approach. Most environmental variables exhibited temporal changes that included time-varying trends and trend reversals. For instance, dissolved organic carbon showed a linear increasing trend while nitrate concentration or conductivity exemplified trend reversal. All trend reversals and cessations of temporal trends in reservoir hydrochemistry (except total phosphorus concentrations) occurred in the late 1980s and during 1990s as a consequence of dramatic socioeconomic changes. After a series of heavy rains in the late 1990s, an administrative decision to increase the flood-retention volume of the reservoir resulted in a significant regime shift in reservoir hydraulic conditions in 1999. Our analyses also highlight the utility of the model selection framework, based on relatively simple extensions of linear regression, to describe temporal trends in reservoir characteristics. This approach can

  6. Short- and Long-Term Feedbacks on Vegetation Water Use: Unifying Evidence from Observations and Modeling

    Science.gov (United States)

    Mackay, D. S.

    2001-05-01

    Recent efforts to measure and model the interacting influences of climate, soil, and vegetation on soil water and nutrient dynamics have identified numerous important feedbacks that produce nonlinear responses. In particular, plant physiological factors that control rates of transpiration respond to soil water deficits and vapor pressure deficits (VPD) in the short-term, and to climate, nutrient cycling and disturbance in the long-term. The starting point of this presentation is the observation that in many systems, in particular forest ecosystems, conservative water use emerges as a result of short-term closure of stomata in response to high evaporative demand, and long-term vegetative canopy development under nutrient limiting conditions. Evidence for important short-term controls is presented from sap flux measurements of stand transpiration, remote sensing, and modeling of transpiration through a combination of physically-based modeling and Monte Carlo analysis. A common result is a strong association between stomatal conductance (gs) and the negative evaporative gain (∂ gs/∂ VPD) associated with the sensitivity of stomatal closure to rates of water loss. The importance of this association from the standpoint of modeling transpiration depends on the degree of canopy-atmosphere coupling. This suggests possible simplifications to future canopy component models for use in watershed and larger-scale hydrologic models for short-term processes. However, further results are presented from theoretical modeling, which suggest that feedbacks between hydrology and vegetation in current long-term (inter-annual to century) models may be too simple, as they do not capture the spatially variable nature of slow nutrient cycling in response to soil water dynamics and site history. Memory effects in the soil nutrient pools can leave lasting effects on more rapid processes associated with soil, vegetation, atmosphere coupling.

  7. Long term trends in world energy demand and supply

    International Nuclear Information System (INIS)

    Frisch, J.

    1992-01-01

    In this address, the author discusses projected changes in fuel use, shifts in energy consumption and projected increases in carbon dioxide emissions. He expects these energy issues to cause geopolitical uncertainties that will complicate attempts to reduce greenhouse gases. There is great concern for the poverty-stricken areas of Asia and Africa. Thirty-five to forty-five percent of their energy needs will be supplied by scarce fuelwood and poor animal and vegetal residues by the year 2020. International cooperation will be needed to alleviate the tensions caused by these inequities of energy supplies

  8. Rice to vegetables: short- versus long-term impact of land-use change on the indigenous soil microbial community.

    Science.gov (United States)

    Sun, Bo; Dong, Zhi-Xing; Zhang, Xue-Xian; Li, Yun; Cao, Hui; Cui, Zong-Li

    2011-08-01

    Land-use change is known to have a significant effect on the indigenous soil microbial community, but it is unknown if there are any general trends regarding how this effect varies over time. Here, we describe a comparative analysis of microbial communities from three adjacent agricultural fields: one-century-old paddy field (OP) and two vegetable fields (new vegetable field (NV) and old vegetable field (OV)) that were established on traditional paddy fields 10 and 100 years ago, respectively. Soil chemical and physical analysis showed that both vegetable fields were more nutrient rich than the paddy field in terms of organic C, total N, total P, and available K. The vegetable fields possessed relatively higher abundance of culturable bacteria, fungi, and specific groups of bacteria (Actinomyces, nitrifying bacteria, and cellulose-decomposing bacteria) but lower levels of microbial biomass C and N. Notably, the decrease of biomass was further confirmed by analysis of seven additional soils in chronosequence sampled from the same area. Next we examined the metabolic diversity of the microbial community using the EcoPlate(TM) system from Biolog Inc. (Hayward, CA, USA). The utilization patterns of 31 unique C substrates (i.e., community-level physiological profile) showed that microorganisms in vegetable soil and paddy soil prefer to use different C substrates (polymeric compounds for NV and OV soils, phenolic acids for OP soil). Principal component analysis and the average well color development data showed that the NV is metabolically more distinct from the OV and OP. The effect was likely attributable to the elevated soil pH in NV soil. Furthermore, we assessed the diversity of soil bacterial populations using the cultivation-independent technology of amplified ribosomal DNA restriction analysis (ARDRA). Results showed that levels of bacterial diversity in OP and NV soils were similar (Shannon's diversity index H = 4.83 and 4.79, respectively), whereas bacteria in

  9. Spatial And Temporal Trends Of Organic Pollutants In Vegetation From Remote And Rural Areas.

    Science.gov (United States)

    Bartrons, Mireia; Catalan, Jordi; Penuelas, Josep

    2016-05-05

    Persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) used in agricultural, industrial, and domestic applications are widely distributed and bioaccumulate in food webs, causing adverse effects to the biosphere. A review of published data for 1977-2015 for a wide range of vegetation around the globe indicates an extensive load of pollutants in vegetation. On a global perspective, the accumulation of POPs and PAHs in vegetation depends on the industrialization history across continents and distance to emission sources, beyond organism type and climatic variables. International regulations initially reduced the concentrations of POPs in vegetation in rural areas, but concentrations of HCB, HCHs, and DDTs at remote sites did not decrease or even increased over time, pointing to a remobilization of POPs from source areas to remote sites. The concentrations of compounds currently in use, PBDEs and PAHs, are still increasing in vegetation. Differential congener specific accumulation is mostly determined by continent-in accordance to the different regulations of HCHs, PCBs and PBDEs in different countries-and by plant type (PAHs). These results support a concerning general accumulation of toxic pollutants in most ecosystems of the globe that for some compounds is still far from being mitigated in the near future.

  10. Panorama 2013 - Short term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, Armelle

    2012-10-01

    The outlook for gas industry development in the short term is clouded by uncertainties (impact of the economic slowdown, competition between energies, price fluctuations, etc.). However, as in 2012, many favorable factors in terms of natural gas supply and demand point to sustained and sustainable growth of this energy. (author)

  11. Monitoring the long term vegetation phenology change in Northeast China from 1982 to 2015.

    Science.gov (United States)

    Yu, Lingxue; Liu, Tingxiang; Bu, Kun; Yan, Fengqin; Yang, Jiuchun; Chang, Liping; Zhang, Shuwen

    2017-11-07

    Global warming has contributed to the extension of the growing season in North Hemisphere. In this paper, we investigated the spatial characteristics of the date of the start of the season (SOS), the date of the end of the season (EOS) and the length of the season (LOS) and their change trends from 1982 to 2015 in Northeast China. Our results showed that there was a significant advance of SOS and a significant delay of EOS, especially in the north part of Northeast China. For the average change slope of EOS in the study area, the delay trend was 0.25 d/y, which was more obvious than the advance trend of -0.13 d/y from the SOS. In particular, the LOS of deciduous needleleaf forest (DNF) and grassland increased with a trend of 0.63 d/y and 0.66 d/y from 1982 to 2015, indicating the growth season increased 21.42 and 22.44 days in a 34-year period, respectively. However, few negative signals were detected nearby Hulun Lake, suggesting that the continuous climate warming in the future may bring no longer growing periods for the grass in the semiarid areas as the drought caused by climate warming may limit the vegetation growth.

  12. Trends in soil-vegetation dynamics in burned Mediterranean pine forests: the effects of soil properties

    Science.gov (United States)

    Wittenberg, L.; Malkinson, D.

    2009-04-01

    Fire can impact a variety of soil physical and chemical properties. These changes may result, given the fire severity and the local conditions, in decreased infiltration and increased runoff and erosion rates. Most of these changes are caused by complex interactions among eco-geomorphic processes which affect, in turn, the rehabilitation dynamics of the soil and the regeneration of the burnt vegetation. Following wildfire events in two forests growing on different soil types, we investigated runoff, erosion, nutrient export (specifically nitrogen and phosphorous) and vegetation recovery dynamics. The Biriya forest site, burned during the 2006 summer, is composed of two dominant lithological types: soft chalk and marl which are relatively impermeable. The rocks are usually overlain by relatively thick, up of to 80 cm, grayish-white Rendzina soil, which contains large amounts of dissolved carbonate. These carbonates serve as a limiting factor for vegetation growth. The planted forest in Biriya is comprised of monospecific stands of Pinus spp. and Cupressus spp. The Mt. Carmel area, which was last burned in the 2005 spring, represents a system of varied Mediterranean landscapes, differentiated by lithology, soils and vegetation. Lithology is mainly composed of limestone, dolomite, and chalk. The dominant soil is Brown Rendzina whilst in some locations Grey Rendzina and Terra Rossa can be found. The local vegetation is composed mainly of a complex of pine (Pinus halepensis), oak (Quercus calliprinos), Pistacia lentiscus and associations At each site several 3X3 m monitoring plots were established to collect runoff and sediment. In-plot vegetation changes were monitored by a sequence of aerial photographs captured using a 6 m pole-mounted camera. At the terra-rosa sites (Mt. Carmel) mean runoff coefficients were 2.18% during the first year after the fire and 1.6% in the second. Mean erosion rates also decreased, from 42 gr/m2 to 4 gr/m2. The recovering vegetation was

  13. The influence of flood frequency, riparian vegetation and threshold on long-term river transport capacity

    Science.gov (United States)

    Croissant, Thomas; Lague, Dimitri; Davy, Philippe

    2016-04-01

    Climate fluctuations at geological timescales control the capacity of rivers to transport sediment with consequences on geochemical cycles, sedimentary basins dynamics and sedimentation/tectonics interactions. While the impact of differential friction generated by riparian vegetation has been studied for individual flood events, its impact on the long-term sediment transport capacity of rivers, modulated by the frequency of floods remains unknown. Here, we investigate this effect on a simplified river-floodplain configuration obeying observed hydraulic scaling laws. We numerically integrate the full-frequency magnitude distribution of discharge events and its impact on the transport capacity of bedload and suspended material for various level of vegetation-linked differential friction. We demonstrate that riparian vegetation by acting as a virtual confinement of the flow i) increases significantly the instantaneous transport capacity of the river independently of the transport mode and ii) increases the long term bedload transport rates as a function of discharge variability. Our results expose the dominance of flood frequency rather than riparian vegetation on the long term sediment transport capacity. Therefore, flood frequency has to be considered when evaluating long-term bedload transport capacity while floodplain vegetation is important only in high discharge variability regimes. By comparing the transport capacity of unconfined alluvial rivers and confined bedrock gorges, we demonstrate that the latter always presents the highest long term transport capacity at equivalent width and slope. The loss of confinement at the transition between bedrock and alluvial river must be compensated by a widening or a steepening of the alluvial channel to avoid infinite storage. Because steepening is never observed in natural system, we compute the alluvial widening factor value that varies between 3 to 11 times the width of the bedrock channel depending on riparian

  14. Analysis of Trends in Vegetation Avhrr-Ndvi Data Across Sokoto ...

    African Journals Online (AJOL)

    The current situation in vegetation productivity across Nigeria and indeed in Sokoto State is being affected by climatic change and other unfavourable environmental conditions. Time-series Remotely Sensed data within Geographic Information System (GIS) environment can be utilized to timely monitor the trajectory in ...

  15. Trends in birth asphyxia, obstetric interventions and perinatal mortality among term singletons: a nationwide cohort study

    NARCIS (Netherlands)

    Ensing, Sabine; Abu-Hanna, Ameen; Schaaf, Jelle M.; Mol, Ben Willem J.; Ravelli, Anita C. J.

    2015-01-01

    The objective of the present study is to investigate trends in birth asphyxia and perinatal mortality in the Netherlands over the last decade. A nationwide cohort study among women with a term singleton pregnancy. We assessed trends in birth asphyxia in relation to obstetric interventions for fetal

  16. Panorama 2010: Short-term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, A.

    2010-01-01

    After a period of strong expansion that lasted for most of 2008, the gas industry was hard hit by the impact of the economic recession. Although the competitiveness of the gas price was often an advantage in 2009, the natural gas market saw a net decline in consumption that led to a historic decrease in world production and international trade. In addition, the subsequent collapse of market prices gave LNG a competitive edge in the Atlantic Basin, where surplus gas continued to accumulate, heralding a long 'gas bubble' period that the industry will have to adjust to permit harmonious, long-term development of the gas markets. (author)

  17. Panorama 2014 - Short term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, Armelle

    2013-12-01

    Due to sustained competition between energy sources and an economic and geopolitical climate that is still unstable, gas growth has slowed. The year 2013 looks very mixed for the gas industry, particularly on the upstream side. Constraints on the supply of gas and the increased dependence on imports in consumer markets increase the vulnerability of the gas markets to the vagaries of geopolitical risks and result in tensions on the international market. In an environment full of uncertainties about future prices and contractual terms, investors are slow to initiate the projects necessary for a global gas balance in this decade. (author)

  18. Limits to detectability of land degradation by trend analysis of vegetation index data

    CSIR Research Space (South Africa)

    Wessels, Konrad J

    2012-10-01

    Full Text Available of reductions in seasonally-summed NDVI are systematically varied on sample data to simulate land degradation, after which the trend analysis was applied and its sensitivity evaluated. The study was based on a widely-used, 1 km2 AVHRR data set for a test area...

  19. NDVI indicated long-term interannual changes in vegetation activities and their responses to climatic and anthropogenic factors in the Three Gorges Reservoir Region, China.

    Science.gov (United States)

    Wen, Zhaofei; Wu, Shengjun; Chen, Jilong; Lü, Mingquan

    2017-01-01

    Natural and social environmental changes in the China's Three Gorges Reservoir Region (TGRR) have received worldwide attention. Identifying interannual changes in vegetation activities in the TGRR is an important task for assessing the impact these changes have on the local ecosystem. We used long-term (1982-2011) satellite-derived Normalized Difference Vegetation Index (NDVI) datasets and climatic and anthropogenic factors to analyze the spatiotemporal patterns of vegetation activities in the TGRR, as well as their links to changes in temperature (TEM), precipitation (PRE), downward radiation (RAD), and anthropogenic activities. At the whole TGRR regional scale, a statistically significant overall uptrend in NDVI variations was observed in 1982-2011. More specifically, there were two distinct periods with different trends split by a breakpoint in 1991: NDVI first sharply increased prior to 1991, and then showed a relatively weak rate of increase after 1991. At the pixel scale, most parts of the TGRR experienced increasing NDVI before the 1990s but different trend change types after the 1990s: trends were positive in forests in the northeastern parts, but negative in farmland in southwest parts of the TGRR. The TEM warming trend was the main climate-related driver of uptrending NDVI variations pre-1990s, and decreasing PRE was the main climate factor (42%) influencing the mid-western farmland areas' NDVI variations post-1990s. We also found that anthropogenic factors such as population density, man-made ecological restoration, and urbanization have notable impacts on the TGRR's NDVI variations. For example, large overall trend slopes in NDVI were more likely to appear in TGRR regions with large fractions of ecological restoration within the last two decades. The findings of this study may help to build a better understanding of the mechanics of NDVI variations in the periods before and during TGDP construction for ongoing ecosystem monitoring and assessment in the

  20. Long-term trends of foE and geomagnetic activity variations

    Directory of Open Access Journals (Sweden)

    A. V. Mikhailov

    2003-03-01

    Full Text Available A relationship between foE trends and geomagnetic activity long-term variations has been revealed for the first time. By analogy with earlier obtained results on the foF2 trends it is possible to speak about the geomagnetic control of the foE long-term trends as well. Periods of increasing geomagnetic activity correspond to negative foE trends, while these trends are positive for the decreasing phase of geomagnetic activity. This "natural" relationship breaks down around 1970 (on some stations later when pronounced positive foE trends have appeared on most of the stations considered. The dependence of foE trends on geomagnetic activity can be related with nitric oxide variations at the E-layer heights. The positive foE trends that appeared after the "break down" effect may also be explained by the [NO] decrease which is not related to geomagnetic activity variations. But negative trends or irregular foE variations on some stations for the same time period require some different mechanism. Chemical pollution of the lower thermosphere due to the anthropogenic activity may be responsible for such abnormal foE behavior after the end of the 1960s.Key words. Ionosphere (ionosphere-atmosphere interactions; ionospheric disturbances

  1. Vegetation cover, tidal amplitude and land area predict short-term marsh vulnerability in Coastal Louisiana

    Science.gov (United States)

    Schoolmaster, Donald; Stagg, Camille L.; Sharp, Leigh Anne; McGinnis, Tommy S.; Wood, Bernard; Piazza, Sarai

    2018-01-01

    The loss of coastal marshes is a topic of great concern, because these habitats provide tangible ecosystem services and are at risk from sea-level rise and human activities. In recent years, significant effort has gone into understanding and modeling the relationships between the biological and physical factors that contribute to marsh stability. Simulation-based process models suggest that marsh stability is the product of a complex feedback between sediment supply, flooding regime and vegetation response, resulting in elevation gains sufficient to match the combination of relative sea-level rise and losses from erosion. However, there have been few direct, empirical tests of these models, because long-term datasets that have captured sufficient numbers of marsh loss events in the context of a rigorous monitoring program are rare. We use a multi-year data set collected by the Coastwide Reference Monitoring System (CRMS) that includes transitions of monitored vegetation plots to open water to build and test a predictive model of near-term marsh vulnerability. We found that despite the conclusions of previous process models, elevation change had no ability to predict the transition of vegetated marsh to open water. However, we found that the processes that drive elevation change were significant predictors of transitions. Specifically, vegetation cover in prior year, land area in the surrounding 1 km2 (an estimate of marsh fragmentation), and the interaction of tidal amplitude and position in tidal frame were all significant factors predicting marsh loss. This suggests that 1) elevation change is likely better a predictor of marsh loss at time scales longer than we consider in this study and 2) the significant predictive factors affect marsh vulnerability through pathways other than elevation change, such as resistance to erosion. In addition, we found that, while sensitivity of marsh vulnerability to the predictive factors varied spatially across coastal Louisiana

  2. Panorama 2011: Short-term trends in the gas industry

    International Nuclear Information System (INIS)

    Lecarpentier, A.

    2011-01-01

    2009 was a particularly bad year for the natural gas industry, with demand falling dramatically by 2.8% as a result of the world economic crisis. However, 2010 appears to have been a very positive year for the industry, with a sustained increase in production and trade. Increased economic activity, together with harsh winters and competitive gas prices are the reasons for the markets having rediscovered their buoyancy. Although the economic recovery has shown signs of fragility in OECD countries, global natural gas demand should continue to grow rapidly in the short-term, driven by consumption in developing countries, suggesting that the gas bubble will be reabsorbed faster than expected on the international markets. (author)

  3. On the relative importance of vegetation terms in computational fluid dynamics on flow and Dispersion in the urban environment

    NARCIS (Netherlands)

    Gromke, C.B.; Blocken, B.J.E.

    2013-01-01

    The relative importance of vegetation terms was analysed for flow and dispersion in an urban street canyon with avenue-trees. To this end, simulations with three k-e turbulence models and different approaches to model vegetation were performed. The different approaches resulted in rather slight

  4. Variability and climate change trend in vegetation phenology of recent decades in the Greater Khingan Mountain area, Northeastern China

    Directory of Open Access Journals (Sweden)

    Huan Tang

    2015-09-01

    Full Text Available Vegetation phenology has been used in studies as an indicator of an ecosystem’s responses to climate change. Satellite remote sensing techniques can capture changes in vegetation greenness, which can be used to estimate vegetation phenology. In this study, a long-term vegetation phenology study of the Greater Khingan Mountain area in Northeastern China was performed by using the Global Inventory Modeling and Mapping Studies (GIMMS normalized difference vegetation index version 3 (NDVI3g dataset from the years 1982–2012. After reconstructing the NDVI time series, the start date of the growing season (SOS, the end date of the growing season (EOS and the length of the growing season (LOS were extracted using a dynamic threshold method. The response of the variation in phenology with climatic factors was also analyzed. The results showed that the phenology in the study area changed significantly in the three decades between 1982 and 2012, including a 12.1-day increase in the entire region’s average LOS, a 3.3-day advance in the SOS and an 8.8-day delay in the EOS. However, differences existed between the steppe, forest and agricultural regions, with the LOSs of the steppe region, forest region and agricultural region increasing by 4.40 days, 10.42 days and 1.71 days, respectively, and a later EOS seemed to more strongly affect the extension of the growing season. Additionally, temperature and precipitation were closely correlated with the phenology variations. This study provides a useful understanding of the recent change in phenology and its variability in this high-latitude study area, and this study also details the responses of several ecosystems to climate change.

  5. Long term spatial and temporal rainfall trends and homogeneity analysis in Wainganga basin, Central India

    Directory of Open Access Journals (Sweden)

    Arun Kumar Taxak

    2014-08-01

    Full Text Available Gridded rainfall data of 0.5×0.5° resolution (CRU TS 3.21 was analysed to study long term spatial and temporal trends on annual and seasonal scales in Wainganga river basin located in Central India during 1901–2012. After testing the presence of autocorrelation, Mann–Kendall (Modified Mann–Kendall test was applied to non-auto correlated (auto correlated series to detect the trends in rainfall data. Theil and Sen׳s slope estimator test was used for finding the magnitude of change over a time period. For detecting the most probable change year, Pettitt–Mann–Whitney test was applied. The Rainfall series was then divided into two partial duration series for finding changes in trends before and after the change year. Arc GIS was used to explore spatial patterns of the trends over the entire basin. Though most of the grid points shows a decreasing trend in annual rainfall, only seven grids has a significant decreasing trend during 1901–2012. On the basis of seasonal trend analysis, non-significant increasing trend is observed only in post monsoon season while seven grid points show significant decreasing trend in monsoon rainfall and non-significant in pre-monsoon and winter rainfall over the last 112 years. During the study period, overall a 8.45% decrease in annual rainfall is estimated. The most probable year of change was found to be 1948 in annual and monsoonal rainfall. There is an increasing rainfall trend in the basin during the period 1901–1948, which is reversed during the period 1949–2012 resulting in decreasing rainfall trend in the basin. Homogeneous trends in annual and seasonal rainfall over a grid points is exhibited in the basin by van Belle and Hughes׳ homogeneity trend test.

  6. Comparison of the long-term trends in stratospheric dynamics of four reanalyses

    Directory of Open Access Journals (Sweden)

    M. Kozubek

    2017-02-01

    Full Text Available Since the long-term trends of different atmospheric parameters have been already studied separately in many papers, this study is focused on the stratospheric wind (zonal and meridional components and temperature over the whole globe at 10 hPa during 1979–2015. We present the trends for the whole winter (October–March, for each individual month of winter and separately for the period before and after the ozone trend turnaround during the mid-1990s. The change of ozone trends has a clear impact on trends in other investigated stratospheric parameters. Four reanalyses (MERRA, ERA-Interim, JRA-55 and NCEP-DOE are used for comparison. Every grid point is analysed, not zonal averages. The comparison of trends in meridional wind, which is closely connected with Brewer–Dobson circulation, shows a good agreement for all four reanalyses (main features and amplitudes of the trends in terms of winter averages, but there are some differences in individual months, particularly in trend amplitude. These results could be important for studying dynamics (transport in the whole stratosphere.

  7. Long-term CO2 fertilization increases vegetation productivity and has little effect on hydrological partitioning in tropical rainforests

    Science.gov (United States)

    Yang, Yuting; Donohue, Randall J.; McVicar, Tim R.; Roderick, Michael L.; Beck, Hylke E.

    2016-08-01

    Understanding how tropical rainforests respond to elevated atmospheric CO2 concentration (eCO2) is essential for predicting Earth's carbon, water, and energy budgets under future climate change. Here we use long-term (1982-2010) precipitation (P) and runoff (Q) measurements to infer runoff coefficient (Q/P) and evapotranspiration (E) trends across 18 unimpaired tropical rainforest catchments. We complement that analysis by using satellite observations coupled with ecosystem process modeling (using both "top-down" and "bottom-up" perspectives) to examine trends in carbon uptake and relate that to the observed changes in Q/P and E. Our results show there have been only minor changes in the satellite-observed canopy leaf area over 1982-2010, suggesting that eCO2 has not increased vegetation leaf area in tropical rainforests and therefore any plant response to eCO2 occurs at the leaf level. Meanwhile, observed Q/P and E also remained relatively constant in the 18 catchments, implying an unchanged hydrological partitioning and thus approximately conserved transpiration under eCO2. For the same period, using a top-down model based on gas exchange theory, we predict increases in plant assimilation (A) and light use efficiency (ɛ) at the leaf level under eCO2, the magnitude of which is essentially that of eCO2 (i.e., 12% over 1982-2010). Simulations from 10 state-of-the-art bottom-up ecosystem models over the same catchments also show that the direct effect of eCO2 is to mostly increase A and ɛ with little impact on E. Our findings add to the current limited pool of knowledge regarding the long-term eCO2 impacts in tropical rainforests.

  8. Long-term trends in stratospheric ozone, temperature, and water vapor over the Indian region

    Science.gov (United States)

    Thankamani Akhil Raj, Sivan; Venkat Ratnam, Madineni; Narayana Rao, Daggumati; Venkata Krishna Murthy, Boddam

    2018-01-01

    We have investigated the long-term trends in and variabilities of stratospheric ozone, water vapor and temperature over the Indian monsoon region using the long-term data constructed from multi-satellite (Upper Atmosphere Research Satellite (UARS MLS and HALOE, 1993-2005), Aura Microwave Limb Sounder (MLS, 2004-2015), Sounding of the Atmosphere using Broadband Emission Radiometry (SABER, 2002-2015) on board TIMED (Thermosphere Ionosphere Mesosphere Energetics Dynamics)) observations covering the period 1993-2015. We have selected two locations, namely, Trivandrum (8.4° N, 76.9° E) and New Delhi (28° N, 77° E), covering northern and southern parts of the Indian region. We also used observations from another station, Gadanki (13.5° N, 79.2° E), for comparison. A decreasing trend in ozone associated with NOx chemistry in the tropical middle stratosphere is found, and the trend turned to positive in the upper stratosphere. Temperature shows a cooling trend in the stratosphere, with a maximum around 37 km over Trivandrum (-1.71 ± 0.49 K decade-1) and New Delhi (-1.15 ± 0.55 K decade-1). The observed cooling trend in the stratosphere over Trivandrum and New Delhi is consistent with Gadanki lidar observations during 1998-2011. The water vapor shows a decreasing trend in the lower stratosphere and an increasing trend in the middle and upper stratosphere. A good correlation between N2O and O3 is found in the middle stratosphere (˜ 10 hPa) and poor correlation in the lower stratosphere. There is not much regional difference in the water vapor and temperature trends. However, upper stratospheric ozone trends over Trivandrum and New Delhi are different. The trend analysis carried out by varying the initial year has shown significant changes in the estimated trend.

  9. Long-term changes and trends in the upper atmosphere - An introduction

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Akmaev, R. A.; Emmert, J. T.

    2009-01-01

    Roč. 71, 14-15 (2009), s. 1511-1513 ISSN 1364-6826 Institutional research plan: CEZ:AV0Z30420517 Keywords : long-term changes * long-term trends * upper atmosphere Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.643, year: 2009 http://www.sciencedirect.com/science/journal/13646826

  10. Long term trending of engineering data for the Hubble Space Telescope

    Science.gov (United States)

    Cox, Ross M.

    1993-01-01

    A major goal in spacecraft engineering analysis is the detection of component failures before the fact. Trending is the process of monitoring subsystem states to discern unusual behaviors. This involves reducing vast amounts of data about a component or subsystem into a form that helps humans discern underlying patterns and correlations. A long term trending system has been developed for the Hubble Space Telescope. Besides processing the data for 988 distinct telemetry measurements each day, it produces plots of 477 important parameters for the entire 24 hours. Daily updates to the trend files also produce 339 thirty day trend plots each month. The total system combines command procedures to control the execution of the C-based data processing program, user-written FORTRAN routines, and commercial off-the-shelf plotting software. This paper includes a discussion the performance of the trending system and of its limitations.

  11. Short-term fluctuations in vegetation and phytoplankton during the Middle Eocene greenhouse climate: a 640-kyr record from the Messel oil shale (Germany)

    Science.gov (United States)

    Lenz, Olaf K.; Wilde, Volker; Riegel, Walter

    2011-11-01

    The Palaeogene was the most recent greenhouse period on Earth. Especially for the Late Palaeocene and Early Eocene, several superimposed short-term hyperthermal events have been described, including extremes such as the Palaeocene-Eocene Thermal Maximum. Major faunal and floral turnovers in the marine and terrestrial realms were recorded in association with these events. High-resolution palynological analysis of the early Middle Eocene maar lake sediments at Messel, near Darmstadt, Germany, provides an insight into the dynamics of a climax vegetation during the Middle Eocene greenhouse climate in a time span without significant climatic excursions. Numerical techniques like detrended correspondence analysis and wavelet analysis have been applied to recognize cyclic fluctuations and long-term trends in the vegetation through a time interval of approximately 640 kyr. Based on the numerical zoning of the pollen diagram, three phases in the development of the vegetation may be distinguished. Throughout these phases, the climax vegetation did not change substantially in qualitative composition, but a trend towards noticeably less humid conditions probably in combination with a drop of the water level in the lake may be recognized. A shift in algal population from the freshwater dinoflagellate cyst Messelodinium thielepfeifferae to a dominance of Botryococcus in the uppermost part of the core is interpreted as a response to changes in acidity and nutrient availability within the lake. Time series analyses of pollen assemblages show that variations in the Milankovitch range of eccentricity, obliquity and precession can be distinguished. In addition, fluctuations in the sub-Milankovitch range are indicated. This demonstrates that floral changes during steady depositional conditions in the Middle Eocene of Messel were controlled by orbital forcing.

  12. Long-term Trends in Catch Composition from Elasmobranch Derbies in Elkhorn Slough, California

    OpenAIRE

    Carlisle, Aaron

    2007-01-01

    Long-term trends in the elasmobranch assemblage of Elkhorn Slough, Monterey Bay, California, were analyzed by documenting species composition and catch per unit effort (CPUE) from 55 sport fishing derbies that occurred during May, June, and July, from 1951 until 1995. The most abundant species (bat ray, Myliobatis californica; shovelnose guitarfish, Rhinobatos productus; and leopard shark, Triakis semifasciata) were also analyzed for size-weight relationships, trends in size class distributio...

  13. Assessing Woody Vegetation Trends in Sahelian Drylands Using MODIS Based Seasonal Metrics

    Science.gov (United States)

    Brandt, Martin; Hiernaux, Pierre; Rasmussen, Kjeld; Mbow, Cheikh; Kergoat, Laurent; Tagesson, Torbern; Ibrahim, Yahaya Z.; Wele, Abdoulaye; Tucker, Compton J.; Fensholt, Rasmus

    2016-01-01

    Woody plants play a major role for the resilience of drylands and in peoples' livelihoods. However, due to their scattered distribution, quantifying and monitoring woody cover over space and time is challenging. We develop a phenology driven model and train/validate MODIS (MCD43A4, 500m) derived metrics with 178 ground observations from Niger, Senegal and Mali to estimate woody cover trends from 2000 to 2014 over the entire Sahel. The annual woody cover estimation at 500 m scale is fairly accurate with an RMSE of 4.3 (woody cover %) and r(exp 2) = 0.74. Over the 15 year period we observed an average increase of 1.7 (+/- 5.0) woody cover (%) with large spatial differences: No clear change can be observed in densely populated areas (0.2 +/- 4.2), whereas a positive change is seen in sparsely populated areas (2.1 +/- 5.2). Woody cover is generally stable in cropland areas (0.9 +/- 4.6), reflecting the protective management of parkland trees by the farmers. Positive changes are observed in savannas (2.5 +/- 5.4) and woodland areas (3.9 +/- 7.3). The major pattern of woody cover change reveals strong increases in the sparsely populated Sahel zones of eastern Senegal, western Mali and central Chad, but a decreasing trend is observed in the densely populated western parts of Senegal, northern Nigeria, Sudan and southwestern Niger. This decrease is often local and limited to woodlands, being an indication of ongoing expansion of cultivated areas and selective logging.We show that an overall positive trend is found in areas of low anthropogenic pressure demonstrating the potential of these ecosystems to provide services such as carbon storage, if not over-utilized. Taken together, our results provide an unprecedented synthesis of woody cover dynamics in theSahel, and point to land use and human population density as important drivers, however only partially and locally offsetting a general post-drought increase.

  14. Long-term trends of foF2 independent of geomagnetic activity

    Directory of Open Access Journals (Sweden)

    A. D. Danilov

    Full Text Available A detailed analysis of the foF2 data at a series of ionospheric stations is performed to reveal long-term trends independent of the long-term changes in geomagnetic activity during the recent decades (nongeomagnetic trends. The method developed by the author and published earlier is used. It is found that the results for 21 out of 23 stations considered agree well and give a relative nongeomagnetic trend of -0.0012 per year (or an absolute nongeomagnetic trend of about -0.012 MHz per year for the period between 1958 and the mid-nineties. The trends derived show no dependence on geomagnetic latitude or local time, a fact confirming their independence of geomagnetic activity. The consideration of the earlier period (1948–1985 for a few stations for which the corresponding data are available provides significantly lower foF2 trends, the difference between the later and earlier periods being a factor of 1.6. This is a strong argument in favor of an anthropogenic nature of the trends derived.Key words. Ionosphere (ionosphere-atmosphere interactions; ionospheric disturbances; mid-latitude ionosphere

  15. A Global Assessment of Long-Term Greening and Browning Trends in Pasture Lands Using the GIMMS LAI3g Dataset

    Directory of Open Access Journals (Sweden)

    Benjamin I. Cook

    2013-05-01

    Full Text Available Pasture ecosystems may be particularly vulnerable to land degradation due to the high risk of human disturbance (e.g., overgrazing, burning, etc., especially when compared with natural ecosystems (non-pasture, non-cultivated where direct human impacts are minimal. Using maximum annual leaf area index (LAImax as a proxy for standing biomass and peak annual aboveground productivity, we analyze greening and browning trends in pasture areas from 1982–2008. Inter-annual variability in pasture productivity is strongly controlled by precipitation (positive correlation and, to a lesser extent, temperature (negative correlation. Linear temporal trends are significant in 23% of pasture cells, with the vast majority of these areas showing positive LAImax trends. Spatially extensive productivity declines are only found in a few regions, most notably central Asia, southwest North America, and southeast Australia. Statistically removing the influence of precipitation reduces LAImax trends by only 13%, suggesting that precipitation trends are only a minor contributor to long-term greening and browning of pasture lands. No significant global relationship was found between LAImax and pasture intensity, although the magnitude of trends did vary between cells classified as natural versus pasture. In the tropics and Southern Hemisphere, the median rate of greening in pasture cells is significantly higher than for cells dominated by natural vegetation. In the Northern Hemisphere extra-tropics, conversely, greening of natural areas is 2–4 times the magnitude of greening in pasture areas. This analysis presents one of the first global assessments of greening and browning trends in global pasture lands, including a comparison with vegetation trends in regions dominated by natural ecosystems. Our results suggest that degradation of pasture lands is not a globally widespread phenomenon and, consistent with much of the terrestrial biosphere, there have been widespread

  16. Restoration treatments in urban park forests drive long-term changes in vegetation trajectories.

    Science.gov (United States)

    Johnson, Lea R; Handel, Steven N

    2016-04-01

    Municipalities are turning to ecological restoration of urban forests as a measure to improve air quality, ameliorate urban heat island effects, improve storm water infiltration, and provide other social and ecological benefits. However, community dynamics following urban forest restoration treatments are poorly documented. This study examines the long-term effects of ecological restoration undertaken in New York City, New York, USA, to restore native forest in urban park natural areas invaded by woody non-native plants that are regional problems. In 2009 and 2010, we sampled vegetation in 30 invaded sites in three large public parks that were restored 1988-1993, and 30 sites in three large parks that were similarly invaded but had not been restored. Data from these matched plots reveal that the restoration treatment achieved its central goals. After 15-20 years, invasive species removal followed by native tree planting resulted in persistent structural and compositional shifts, significantly lower invasive species abundance, a more complex forest structure, and greater native tree recruitment. Together, these findings indicate that successional trajectories of vegetation dynamics have diverged between restored forests and invaded forests that were not restored. In addition, the data suggest that future composition of these urban forest patches will be novel assemblages. Restored and untreated sites shared a suite of shade-intolerant, quickly-growing tree species that colonize disturbed sites, indicating that restoration treatments created sites hospitable for germination and growth of species adapted to high light conditions and disturbed soils. These findings yield an urban perspective on the use of succession theory in ecological restoration. Models of ecological restoration developed in more pristine environments must be modified for use in cities. By anticipating both urban disturbances and ecological succession, management of urban forest patches can be

  17. Google Trends terms reporting rhinitis and related topics differ in European countries.

    Science.gov (United States)

    Bousquet, J; Agache, I; Anto, J M; Bergmann, K C; Bachert, C; Annesi-Maesano, I; Bousquet, P J; D'Amato, G; Demoly, P; De Vries, G; Eller, E; Fokkens, W J; Fonseca, J; Haahtela, T; Hellings, P W; Just, J; Keil, T; Klimek, L; Kuna, P; Lodrup Carlsen, K C; Mösges, R; Murray, R; Nekam, K; Onorato, G; Papadopoulos, N G; Samolinski, B; Schmid-Grendelmeier, P; Thibaudon, M; Tomazic, P; Triggiani, M; Valiulis, A; Valovirta, E; Van Eerd, M; Wickman, M; Zuberbier, T; Sheikh, A

    2017-08-01

    Google Trends (GT) searches trends of specific queries in Google and reflects the real-life epidemiology of allergic rhinitis. We compared Google Trends terms related to allergy and rhinitis in all European Union countries, Norway and Switzerland from 1 January 2011 to 20 December 2016. The aim was to assess whether the same terms could be used to report the seasonal variations of allergic diseases. Using the Google Trend 5-year graph, an annual and clear seasonality of queries was found in all countries apart from Cyprus, Estonia, Latvia, Lithuania and Malta. Different terms were found to demonstrate seasonality depending on the country - namely 'hay fever', 'allergy' and 'pollen' - showing cultural differences. A single set of terms cannot be used across all European countries, but allergy seasonality can be compared across Europe providing the above three terms are used. Using longitudinal data in different countries and multiple terms, we identified an awareness-related spike of searches (December 2016). © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Is there an upward long term trend in Danish real house prices?

    DEFF Research Database (Denmark)

    Skak, Morten

    2012-01-01

    In Denmark, like in other countries, there is no agreement on the fundamental long term path of real house prices and the sustainability of the present price level. The paper presents Danish house price indices and discusses the question of quality correction of the indices. Subsequently, factors...... behind the long term trend in real house prices and its sustainability are discussed. The paper finds an annual real growth trend around 1.5 per cent for Danish single family house prices likely for the coming ten years....

  19. Long-term trends in the ionospheric E and F1 regions

    Directory of Open Access Journals (Sweden)

    J. Bremer

    2008-05-01

    Full Text Available Ground based ionosonde measurements are the most essential source of information about long-term variations in the ionospheric E and F1 regions. Data of such observations have been derived at many different ionospheric stations all over the world some for more than 50 years. The standard parameters foE, h'E, and foF1 are used for trend analyses in this paper. Two main problems have to be considered in these analyses. Firstly, the data series have to be homogeneous, i.e. the observations should not be disturbed by artificial steps due to technical reasons or changes in the evaluation algorithm. Secondly, the strong solar and geomagnetic influences upon the ionospheric data have carefully to be removed by an appropriate regression analysis. Otherwise the small trends in the different ionospheric parameters cannot be detected.

    The trends derived at individual stations differ markedly, however their dependence on geographic or geomagnetic latitude is only small. Nevertheless, the mean global trends estimated from the trends at the different stations show some general behaviour (positive trends in foE and foF1, negative trend in h'E which can at least qualitatively be explained by an increasing atmospheric greenhouse effect (increase of CO2 content and other greenhouse gases and decreasing ozone values. The positive foE trend is also in qualitative agreement with rocket mass spectrometer observations of ion densities in the E region. First indications could be found that the changing ozone trend at mid-latitudes (before about 1979, between 1979 until 1995, and after about 1995 modifies the estimated mean foE trend.

  20. Short-term responses of decomposers and vegetation to stump removal

    Energy Technology Data Exchange (ETDEWEB)

    Kataja-aho, S.

    2011-07-01

    Stump removal has become a common practice to produce raw material for bioenergy production. It was hypothesized that stump removal is an extensive and more intense disturbance for forest ecosystems (soil decomposer organisms and vegetation) compared to traditional site preparation after clear cutting. Therefore, the effects of stump harvesting on forest soil decomposers, vegetation and nutrient dynamics in undisturbed patches of the forest soil and in exposed mineral soil were compared to the effects of the traditional site preparation method, mounding. Nematodes and enchytraeids were the only decomposer groups that were directly affected (negatively) by the stump removal. Regardless of the treatment, the abundances of most of the decomposer groups were consistently lower in the exposed mineral soil than in the intact forest soil. There was 2-3 times more exposed mineral soil in stump removal sites compared to mounding sites. When this was taken into account, the decomposer community was negatively affected by the stump removal at the forest stand level. However, the greater soil disturbance at the stump harvesting sites enhanced CO{sub 2} production, net nitrogen mineralisation and nitrification. The increased N availability and the changes in microclimate due to the disturbance probably explained the vegetation increase at the stump harvested sites. Planted Norway spruce seedlings grew faster during the first two growing periods at the stump removal sites than at the mounding sites. The seedlings had high and similar ectomycorrhizal colonization rate in both treatments. In the short-term, it is probably not the resources removed in the stumps themselves, but the degree and amount of soil disturbance during the stump harvesting procedure that affects the decomposer community and its function in the clear-felled stands. (orig.)

  1. Chances of short-term cooling trends over Canada for the next decades

    Science.gov (United States)

    Grenier, Patrick; de Elia, Ramon; Chaumont, Diane

    2014-05-01

    As climate services continue to develop in Quebec, Canada, an increasing number of requests are made for providing information relevant for the near term. As a response, one approach has been to consider short-term cooling trends as a basis for climate products. This project comprises different aspects: technical steps, knowledge transfer, and societal use. Each step does represent a different challenge. The technical part, i.e. producing probabilistic distributions of short-term temperature trends, involves relatively complex scenario construction methods including bias-related post-processing, and access to wide simulation and observation databases. Calculations are performed on 60 CMIP5-based scenarios on a grid covering Canada during the period 2006-2035, and for 5, 10, 15, 20 and 25-year trend durations. Knowledge transfer implies overcoming misinterpretation, given that probabilistic projections based on simulation ensembles are not perfectly related to real-Earth possible outcomes. Finally, societal use of this information remains the biggest challenge. On the one hand, users clearly state their interest in near-term relevant information, and intuitively it seems clear that short-term cooling trends embedded within the long-term warming path should be considered in adaptation plans, for avoiding over-adaptation. On the other hand, the exact way of incorporating such information within a decision-making process has proven not to be obvious. Irrespective of that, the study and communication of short-term cooling chances is necessary for preventing decision-makers to infer from the eventual occurrence of such a trend that global warming isn't happening. The presentation will discuss the three aspects aforementioned.

  2. Long-term trend of foE in European higher middle latitudes

    Science.gov (United States)

    Laštovička, Jan

    2016-04-01

    Long-term changes and trends have been observed in the whole ionosphere below its maximum. As concerns the E region, historical global data (Bremer, 2008) provide predominantly slightly positive trend, even though some stations provide a negative trend. Here we use data of two European stations with the best long data series of parameters of the ionospheric E layer, Slough/Chilton and Juliusruh over 1975-2014 (40 years). Noon-time medians (10-14 LT) are analyzed. The trend pattern after removing solar influence is complex. For yearly average values for Chilton first foE is decreasing in 1975-1990 by about 0.1 MHz, then the trend levels off or a little increase occurs in 1990-2004, and finally in 2004-2014 again a decrease is observed (again by about 0.1 MHz but over shorter period). Juliusruh yields a similar pattern. Similar analysis is also done for some months to check seasonal dependence of trends. The stability of relation between solar activity and foE is tested to clarify potential role of this factor in apparent trend of foE.

  3. Global long-term ozone trends derived from different observed and modelled data sets

    Science.gov (United States)

    Coldewey-Egbers, M.; Loyola, D.; Zimmer, W.; van Roozendael, M.; Lerot, C.; Dameris, M.; Garny, H.; Braesicke, P.; Koukouli, M.; Balis, D.

    2012-04-01

    The long-term behaviour of stratospheric ozone amounts during the past three decades is investigated on a global scale using different observed and modelled data sets. Three European satellite sensors GOME/ERS-2, SCIAMACHY/ENVISAT, and GOME-2/METOP are combined and a merged global monthly mean total ozone product has been prepared using an inter-satellite calibration approach. The data set covers the 16-years period from June 1995 to June 2011 and it exhibits an excellent long-term stability, which is required for such trend studies. A multiple linear least-squares regression algorithm using different explanatory variables is applied to the time series and statistically significant positive trends are detected in the northern mid latitudes and subtropics. Global trends are also estimated using a second satellite-based Merged Ozone Data set (MOD) provided by NASA. For few selected geographical regions ozone trends are additionally calculated using well-maintained measurements of individual Dobson/Brewer ground-based instruments. A reasonable agreement in the spatial patterns of the trends is found amongst the European satellite, the NASA satellite, and the ground-based observations. Furthermore, two long-term simulations obtained with the Chemistry-Climate Models E39C-A provided by German Aerospace Center and UMUKCA-UCAM provided by University of Cambridge are analysed.

  4. Long-Term Warming Trends in Korea and Contribution of Urbanization: An Updated Assessment

    Science.gov (United States)

    Park, Bo-Joung; Kim, Yeon-Hee; Min, Seung-Ki; Kim, Maeng-Ki; Choi, Youngeun; Boo, Kyung-On; Shim, Sungbo

    2017-10-01

    This study conducted an updated analysis of the long-term temperature trends over South Korea and reassessed the contribution of the urbanization effect to the local warming trends. Linear trends were analyzed for three different periods over South Korea in order to consider possible inhomogeneity due to changes in the number of available stations: recent 103 years (1912-2014), 61 years (1954-2014), and 42 years (1973-2014). The local temperature has increased by 1.90°C, 1.35°C, and 0.99°C during the three periods, respectively, which are found 1.4-2.6 times larger than the global land mean trends. The countries located in the northern middle and high latitudes exhibit similar warming trends (about 1.5 times stronger than the global mean), suggesting a weak influence of urbanization on the local warming over South Korea. Urbanization contribution is assessed using two methods. First, results from "city minus rural" methods showed that 30-45% of the local warming trends during recent four decades are likely due to the urbanization effect, depending on station classification methods and analysis periods. Results from an "observation minus reanalysis" method using the Twentieth Century Reanalysis (20CR) data sets (v2 and v2c) indicated about 25-30% contribution of the urbanization effect to the local warming trend during the recent six decades. However, the urbanization contribution was estimated as low as 3-11% when considering the century-long period. Our results confirm large uncertainties in the estimation of urbanization contribution when using shorter-term periods and suggest that the urbanization contribution to the century-long warming trends could be much lower.

  5. Long-term trend analysis on total and extreme precipitation over Shasta Dam watershed.

    Science.gov (United States)

    Toride, Kinya; Cawthorne, Dylan L; Ishida, Kei; Kavvas, M Levent; Anderson, Michael L

    2018-06-01

    California's interconnected water system is one of the most advanced water management systems in the world, and understanding of long-term trends in atmospheric and hydrologic behavior has increasingly being seen as vital to its future well-being. Knowledge of such trends is hampered by the lack of long-period observation data and the uncertainty surrounding future projections of atmospheric models. This study examines historical precipitation trends over the Shasta Dam watershed (SDW), which lies upstream of one of the most important components of California's water system, Shasta Dam, using a dynamical downscaling methodology that can produce atmospheric data at fine time-space scales. The Weather Research and Forecasting (WRF) model is employed to reconstruct 159years of long-term hourly precipitation data at 3km spatial resolution over SDW using the 20th Century Reanalysis Version 2c dataset. Trend analysis on this data indicates a significant increase in total precipitation as well as a growing intensity of extreme events such as 1, 6, 12, 24, 48, and 72-hour storms over the period of 1851 to 2010. The turning point of the increasing trend and no significant trend periods is found to be 1940 for annual precipitation and the period of 1950 to 1960 for extreme precipitation using the sequential Mann-Kendall test. Based on these analysis, we find the trends at the regional scale do not necessarily apply to the watershed-scale. The sharp increase in the variability of annual precipitation since 1970s is also detected, which implies an increase in the occurrence of extreme wet and dry conditions. These results inform long-term planning decisions regarding the future of Shasta Dam and California's water system. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Long term trends in oral antidiabetic drug use among children and adolescents in the Netherlands

    NARCIS (Netherlands)

    S. Fazeli Farsani; P. Souverein (Patrick); J.A. Overbeek (Jetty); M.M.J. Van Der Vorst; C.A.J. Knibbe (Catherijne); R.M.C. Herings (Ron); A.C. de Boer (Anton); A.K. Mantel-Teeuwisse (Aukje)

    2015-01-01

    textabstractAim The aim of the study was to document long term trends in oral antidiabetic drug (OAD) use among children and adolescents in the Netherlands. Methods A population-based cohort study was conducted using the Dutch PHARMO Database Network. All patients younger than 20 years old with at

  7. Long term trends in oral antidiabetic drug use among children and adolescents in the Netherlands

    NARCIS (Netherlands)

    Fazeli Farsani, S; Souverein, P C; Overbeek, J A; van der Vorst, M M J; Knibbe, C A J; Herings, R M C; de Boer, Anthonius; Mantel-Teeuwisse, A K

    AIM: The aim of the study was to document long term trends in oral antidiabetic drug (OAD) use among children and adolescents in the Netherlands. METHODS: A population-based cohort study was conducted using the Dutch PHARMO Database Network. All patients younger than 20 years old with at least one

  8. Long-term trends in foF2: A comparison of various methods

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Mikhailov, A. V.; Ulich, T.; Bremer, J.; Elias, A. G.; Ortiz de Adler, N.; Jara, V.; Abarca del Rio, R.; Foppiano, A. J.; Ovalle, E.; Danilov, A. D.

    2006-01-01

    Roč. 68, č. 17 (2006), s. 1854-1870 ISSN 1364-6826 Institutional research plan: CEZ:AV0Z30420517 Keywords : Ionosphere * foF2 * Long-term trends * Anthropogenic effects Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.448, year: 2006

  9. Long-term trends and interannual variability of forest, savanna and agricultural fires in South America

    NARCIS (Netherlands)

    Chen, Y.; Morton, D. C.; Yin, Y. F.; Collatz, G. J.; Kasibhatla, P. S.; van der Werf, G.R.; DeFries, R. S.; Randerson, J. T.

    2013-01-01

    Background: Landscape fires in South America have considerable impacts on ecosystems, air quality and the climate system. We examined long-term trends and interannual variability of forest, savanna and agricultural fires for the continent during 2001-2012 using multiple satellite-derived fire

  10. Long-term trends from ecosystem research at the Hubbard Brook Experimental Forest

    Science.gov (United States)

    John L. Campbell; Charles T. Driscoll; Christopher Eagar; Gene E. Likens; Thomas G. Siccama; Chris E. Johnson; Timothy J. Fahey; Steven P. Hamburg; Richard T. Holmes; Amey S. Bailey; Donald C. Buso

    2007-01-01

    Summarizes 52 years of collaborative, long-term research conducted at the Hubbard Brook (NH) Experimental Forest on ecosystem response to disturbances such as air pollution, climate change, forest disturbance, and forest management practices. Also provides explanations of some of the trends and lists references from scientific literature for further reading.

  11. Short-term responses of wetland vegetation after liming of an Adirondack watershed

    Energy Technology Data Exchange (ETDEWEB)

    Mackun, I.R.; Leopold, D.J.; Raynal, D.J. (State Univ. of New York, Syracuse, NY (United States))

    1994-08-01

    Watershed liming has been suggested as a long-term mitigation strategy for lake acidity, particularly in areas subject to high levels of acidic deposition. However, virtually no information has been available on the impacts of liming on wetland vegetation. In 1989, 1100 Mg of limestone (83.5% CaCO[sub 3]) were aerially applied to 48% (100 ha) of the Woods Lake watershed in the west-central Adirondack region of New York as part of the first comprehensive watershed liming study in North America. We inventoried wetland vegetation in 1.0-m[sup 2] plots before liming and during the subsequent 2 yr. Within this period liming influenced the cover, frequency, or importance values of only 6 of 64 wetland taxa. The cover of Sphagnum spp. and of the cespitose sedge Carex interior decreased in control relative to limed plots, and cover of the rhizomatous sedge Cladium mariscoides increased nearly threefold in limed areas. These two sedges, which are relatively tall, are characteristic of more calcareous habitats. Cover of the grass Muhlenbergia uniflora, cover and importance were adversely affected or inhibited by lime. It is unclear whether liming directly inhibited the growth of these three small-statured species, or whether the adverse effects of lime were mediated through shifts in competitive interactions with other species. The limited responses that we observed to liming, along with changes that occurred in control plots over the study period, may indicate that in the short term watershed liming was no more of a perturbation than the environmental factors responsible for natural annual variation in wetland communities.

  12. Long-term trends in stratospheric ozone, temperature, and water vapor over the Indian region

    Directory of Open Access Journals (Sweden)

    S. T. Akhil Raj

    2018-01-01

    Full Text Available We have investigated the long-term trends in and variabilities of stratospheric ozone, water vapor and temperature over the Indian monsoon region using the long-term data constructed from multi-satellite (Upper Atmosphere Research Satellite (UARS MLS and HALOE, 1993–2005, Aura Microwave Limb Sounder (MLS, 2004–2015, Sounding of the Atmosphere using Broadband Emission Radiometry (SABER, 2002–2015 on board TIMED (Thermosphere Ionosphere Mesosphere Energetics Dynamics observations covering the period 1993–2015. We have selected two locations, namely, Trivandrum (8.4° N, 76.9° E and New Delhi (28° N, 77° E, covering northern and southern parts of the Indian region. We also used observations from another station, Gadanki (13.5° N, 79.2° E, for comparison. A decreasing trend in ozone associated with NOx chemistry in the tropical middle stratosphere is found, and the trend turned to positive in the upper stratosphere. Temperature shows a cooling trend in the stratosphere, with a maximum around 37 km over Trivandrum (−1.71 ± 0.49 K decade−1 and New Delhi (−1.15 ± 0.55 K decade−1. The observed cooling trend in the stratosphere over Trivandrum and New Delhi is consistent with Gadanki lidar observations during 1998–2011. The water vapor shows a decreasing trend in the lower stratosphere and an increasing trend in the middle and upper stratosphere. A good correlation between N2O and O3 is found in the middle stratosphere (∼ 10 hPa and poor correlation in the lower stratosphere. There is not much regional difference in the water vapor and temperature trends. However, upper stratospheric ozone trends over Trivandrum and New Delhi are different. The trend analysis carried out by varying the initial year has shown significant changes in the estimated trend.

  13. Short-term trends in vegetation cover of Danish semi-natural ecosystems

    DEFF Research Database (Denmark)

    Timmermann, Allan; Damgaard, Christian; Strandberg, Morten Tune

    The landscapes in which many plant communities persist today are increasingly modified by anthropogenic activities, especially in Denmark, where most communities are influenced by for example atmospheric deposition of Nitrogen, changes in soil moisture levels (e.g. ground water-table changes caused...... species with similar traits to respond similarly to systematic shifts in habitat conditions and disturbance. Consequently, contrasting traits of winner and loser species could be a powerful tool in identifying mechanisms that might be driving community changes. In this study, we use a large dataset....... Notably, do winner and loser species display distinct sets of traits of the ones related to: exotic species invasion, eutrophication by nitrogen deposition, management changes (decreasing grazing and associated encroachment by woody plants), soil moisture changes (due to excessive water extraction...

  14. Effects of a long-term disturbance on arthropods and vegetation in subalpine wetlands: manifestations of pack stock grazing in early versus mid-season.

    Directory of Open Access Journals (Sweden)

    Jeffrey G Holmquist

    Full Text Available Conclusions regarding disturbance effects in high elevation or high latitude ecosystems based solely on infrequent, long-term sampling may be misleading, because the long winters may erase severe, short-term impacts at the height of the abbreviated growing season. We separated a long-term effects of pack stock grazing, manifested in early season prior to stock arrival, from b additional pack stock grazing effects that might become apparent during annual stock grazing, by use of paired grazed and control wet meadows that we sampled at the beginning and end of subalpine growing seasons. Control meadows had been closed to grazing for at least two decades, and meadow pairs were distributed across Sequoia National Park, California, USA. The study was thus effectively a landscape-scale, long-term manipulation of wetland grazing. We sampled arthropods at these remote sites and collected data on associated vegetation structure. Litter cover and depth, percent bare ground, and soil strength had negative responses to grazing. In contrast, fauna showed little response to grazing, and there were overall negative effects for only three arthropod families. Mid-season and long-term results were generally congruent, and the only indications of lower faunal diversity on mid-season grazed wetlands were trends of lower abundance across morphospecies and lower diversity for canopy fauna across assemblage metrics. Treatment x Season interactions almost absent. Thus impacts on vegetation structure only minimally cascaded into the arthropod assemblage and were not greatly intensified during the annual growing season. Differences between years, which were likely a response to divergent snowfall patterns, were more important than differences between early and mid-season. Reliance on either vegetation or faunal metrics exclusively would have yielded different conclusions; using both flora and fauna served to provide a more integrative view of ecosystem response.

  15. Effects of a long-term disturbance on arthropods and vegetation in subalpine wetlands: manifestations of pack stock grazing in early versus mid-season.

    Science.gov (United States)

    Holmquist, Jeffrey G; Schmidt-Gengenbach, Jutta; Haultain, Sylvia A

    2013-01-01

    Conclusions regarding disturbance effects in high elevation or high latitude ecosystems based solely on infrequent, long-term sampling may be misleading, because the long winters may erase severe, short-term impacts at the height of the abbreviated growing season. We separated a) long-term effects of pack stock grazing, manifested in early season prior to stock arrival, from b) additional pack stock grazing effects that might become apparent during annual stock grazing, by use of paired grazed and control wet meadows that we sampled at the beginning and end of subalpine growing seasons. Control meadows had been closed to grazing for at least two decades, and meadow pairs were distributed across Sequoia National Park, California, USA. The study was thus effectively a landscape-scale, long-term manipulation of wetland grazing. We sampled arthropods at these remote sites and collected data on associated vegetation structure. Litter cover and depth, percent bare ground, and soil strength had negative responses to grazing. In contrast, fauna showed little response to grazing, and there were overall negative effects for only three arthropod families. Mid-season and long-term results were generally congruent, and the only indications of lower faunal diversity on mid-season grazed wetlands were trends of lower abundance across morphospecies and lower diversity for canopy fauna across assemblage metrics. Treatment x Season interactions almost absent. Thus impacts on vegetation structure only minimally cascaded into the arthropod assemblage and were not greatly intensified during the annual growing season. Differences between years, which were likely a response to divergent snowfall patterns, were more important than differences between early and mid-season. Reliance on either vegetation or faunal metrics exclusively would have yielded different conclusions; using both flora and fauna served to provide a more integrative view of ecosystem response.

  16. Long-Term Trend Analysis of Precipitation and Air Temperature for Kentucky, United States

    Directory of Open Access Journals (Sweden)

    Somsubhra Chattopadhyay

    2016-02-01

    Full Text Available Variation in quantities such as precipitation and temperature is often assessed by detecting and characterizing trends in available meteorological data. The objective of this study was to determine the long-term trends in annual precipitation and mean annual air temperature for the state of Kentucky. Non-parametric statistical tests were applied to homogenized and (as needed pre-whitened annual series of precipitation and mean air temperature during 1950–2010. Significant trends in annual precipitation were detected (both positive, averaging 4.1 mm/year for only two of the 60 precipitation-homogenous weather stations (Calloway and Carlisle counties in rural western Kentucky. Only three of the 42 temperature-homogenous stations demonstrated trends (all positive, averaging 0.01 °C/year in mean annual temperature: Calloway County, Allen County in southern-central Kentucky, and urbanized Jefferson County in northern-central Kentucky. In view of the locations of the stations demonstrating positive trends, similar work in adjacent states will be required to better understand the processes responsible for those trends and to properly place them in their larger context, if any.

  17. Emerging medical informatics research trends detection based on MeSH terms.

    Science.gov (United States)

    Lyu, Peng-Hui; Yao, Qiang; Mao, Jin; Zhang, Shi-Jing

    2015-01-01

    The aim of this study is to analyze the research trends of medical informatics over the last 12 years. A new method based on MeSH terms was proposed to identify emerging topics and trends of medical informatics research. Informetric methods and visualization technologies were applied to investigate research trends of medical informatics. The metric of perspective factor (PF) embedding MeSH terms was appropriately employed to assess the perspective quality for journals. The emerging MeSH terms have changed dramatically over the last 12 years, identifying two stages of medical informatics: the "medical imaging stage" and the "medical informatics stage". The focus of medical informatics has shifted from acquisition and storage of healthcare data by integrating computational, informational, cognitive and organizational sciences to semantic analysis for problem solving and clinical decision-making. About 30 core journals were determined by Bradford's Law in the last 3 years in this area. These journals, with high PF values, have relative high perspective quality and lead the trend of medical informatics.

  18. The Vegetation Trends and Drivers in Beijing-Tianjing Region from 1982 TO 2013 Based on Time Series Gimms NDVI3g

    Science.gov (United States)

    Liu, S.; Tian, H.; Wang, X.; Li, H.; He, Y.

    2018-04-01

    Vegetation plays a leading role in ecosystems. Plant communities are the main components of ecosystems. Green plants in ecosystems are the primary producers, and they provide the living organic matter for the survival of other organisms. The dynamics of most landscapes are driven by both natural processes and human activities. In this study, the growing season GIMMS NDVI3g and climatic data were used to analyse the vegetation trends and drivers in Beijing-Tianjin-Hebei region from 1982 to 2013. Result shows that, the vegetation in Beijing-Tianjin-Hebei region shows overall restoration and partial degradation trend. The significant restoration region accounts for 61.5 % of Beijing-Tianjin-Hebei region, while the significant degradation region accounts for 2.1 %. The dominant climatic factor for time series NDVI were analyzed using the multi-linear regression model. Vegetation growth in 17.9 % of Beijing-Tianjin-Hebei region is dominated by temperature, 35.5 % is dominated by precipitation, and 11.68 % is dominated by solar radiance. Human activities play important role for vegetation restoration in Beijing-Tianjin-Hebei Region, where the large scale forest restoration programs are the main human activities, such as the three-north shelterbelt construction project, Beijing-Tianjin-Hebei sandstorm source control project and grain for green projects.

  19. THE VEGETATION TRENDS AND DRIVERS IN BEIJING-TIANJING-HEIBEI REGION FROM 1982 TO 2013 BASED ON TIME SERIES GIMMS NDVI3g

    Directory of Open Access Journals (Sweden)

    S. Liu

    2018-04-01

    Full Text Available Vegetation plays a leading role in ecosystems. Plant communities are the main components of ecosystems. Green plants in ecosystems are the primary producers, and they provide the living organic matter for the survival of other organisms. The dynamics of most landscapes are driven by both natural processes and human activities. In this study, the growing season GIMMS NDVI3g and climatic data were used to analyse the vegetation trends and drivers in Beijing-Tianjin-Hebei region from 1982 to 2013. Result shows that, the vegetation in Beijing-Tianjin-Hebei region shows overall restoration and partial degradation trend. The significant restoration region accounts for 61.5 % of Beijing-Tianjin-Hebei region, while the significant degradation region accounts for 2.1 %. The dominant climatic factor for time series NDVI were analyzed using the multi-linear regression model. Vegetation growth in 17.9 % of Beijing-Tianjin-Hebei region is dominated by temperature, 35.5 % is dominated by precipitation, and 11.68 % is dominated by solar radiance. Human activities play important role for vegetation restoration in Beijing-Tianjin-Hebei Region, where the large scale forest restoration programs are the main human activities, such as the three-north shelterbelt construction project, Beijing-Tianjin-Hebei sandstorm source control project and grain for green projects.

  20. Long-Term and Seasonal Trends in Estuarine and Coastal Carbonate Systems

    DEFF Research Database (Denmark)

    Carstensen, Jacob; Chierici, Melissa; Gustafsson, Bo G.

    2018-01-01

    Coastal pH and total alkalinity are regulated by a diverse range of local processes superimposed on global trends of warming and ocean acidification, yet few studies have investigated the relative importance of different processes for coastal acidification. We describe long-term (1972...... for a pH decrease of 0.0008year(-1). Accounting for mixing, salinity, and temperature effects on dissociation and solubility constants, the resulting pH decline (0.0040year(-1)) was about twice the ocean trend, emphasizing the effect of nutrient management on primary production and coastal acidification....... Coastal pCO(2) increased similar to 4 times more rapidly than ocean rates, enhancing CO2 emissions to the atmosphere. Indeed, coastal systems undergo more drastic changes than the ocean and coastal acidification trends are substantially enhanced from nutrient reductions to address coastal eutrophication....

  1. Contribution of changing risk factors to the trend in breech presentation at term.

    Science.gov (United States)

    Bin, Yu Sun; Roberts, Christine L; Nicholl, Michael C; Nassar, Natasha; Ford, Jane B

    2016-12-01

    Recent population-wide changes in perinatal risk factors may affect rates of breech presentation at birth, and have implications for the provision of breech services and training in breech management. To investigate whether changes in maternal and pregnancy characteristics explain the observed trend in breech presentation at term. All singleton term (≥37 week) births in New South Wales during 2002-2012 were identified through birth and associated hospital records. Annual rates of breech presentation were determined. Logistic regression modelling was used to predict expected rates of breech presentation and these were compared with observed rates over time. A priori predictors included maternal age, country of birth, parity, smoking during pregnancy, diabetes, pregnancy hypertension, placenta praevia, previous singleton term breech, previous caesarean section, infant sex, gestational age, birthweight and congenital anomalies. Hospital and Medicare data were used to assess concomitant trends in external cephalic version. Among 914 147 singleton term births, 3.1% were breech at delivery. Rates of breech presentation declined from 3.6% in 2002 to 2.7% in 2012 (test for trend P breech presentation and previous caesarean section. However, use of external cephalic version appears to have increased over time. Breech presentation at delivery has decreased in New South Wales. Increased use of external cephalic version likely accounts for this decline, as changes in risk factors do not. © 2016 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  2. Long-term trends of heat stress and energy use implications in subtropical climates

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Joseph C.; Wan, Kevin K.W.; Wong, S.L.; Lam, Tony N.T. [Building Energy Research Group, Department of Building and Construction, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR (China)

    2010-02-15

    Past and future trends of human comfort in terms of heat and cold stresses under the local subtropical climates using measured meteorological data as well as predictions from general climate models were investigated. Summer discomfort showed an increasing trend (and winter discomfort a decreasing trend) over the past 41 years from 1968 to 2008. Monthly mean minimum and maximum temperatures and moisture content predictions from a general climate model (MIROC3.2-H) were used to determine summer and winter discomfort for future years (2009-2100) based on two emissions scenarios B1 and A1B (low and medium forcing). The 92-year (2009-2100) mean cold stress would be reduced from the 41-year (1968-2008) mean value of 8.7 to about three for both emissions scenarios. The 92-year mean heat stress would be 115.9 and 120.6 for B1 and A1B, respectively, representing 31.6% and 36.9% increase over the 1968-2008 long-term average of 88.1. These suggest that the already small winter heating requirement in subtropical Hong Kong would become even more insignificant in future years, whereas the increasing trend of summer discomfort would result in more cooling demand in the built environment. (author)

  3. Long-term effects of seeding after wildfire on vegetation in Great Basin shrubland ecosystems

    Science.gov (United States)

    Knutson, Kevin C.; Pyke, David A.; Wirth, Troy A.; Arkle, Robert S.; Pilliod, David S.; Brooks, Matthew L.; Chambers, Jeanne C.; Grace, James B.

    2014-01-01

    1. Invasive annual grasses alter fire regimes in shrubland ecosystems of the western USA, threatening ecosystem function and fragmenting habitats necessary for shrub-obligate species such as greater sage-grouse. Post-fire stabilization and rehabilitation treatments have been administered to stabilize soils, reduce invasive species spread and restore or establish sustainable ecosystems in which native species are well represented. Long-term effectiveness of these treatments has rarely been evaluated. 2. We studied vegetation at 88 sites where aerial or drill seeding was implemented following fires between 1990 and 2003 in Great Basin (USA) shrublands. We examined sites on loamy soils that burned only once since 1970 to eliminate confounding effects of recurrent fire and to assess soils most conducive to establishment of seeded species. We evaluated whether seeding provided greater cover of perennial seeded species than burned–unseeded and unburned–unseeded sites, while also accounting for environmental variation. 3. Post-fire seeding of native perennial grasses generally did not increase cover relative to burned–unseeded areas. Native perennial grass cover did, however, increase after drill seeding when competitive non-natives were not included in mixes. Seeding non-native perennial grasses and the shrub Bassia prostrata resulted in more vegetative cover in aerial and drill seeding, with non-native perennial grass cover increasing with annual precipitation. Seeding native shrubs, particularly Artemisia tridentata, did not increase shrub cover or density in burned areas. Cover of undesirable, non-native annual grasses was lower in drill seeded relative to unseeded areas, but only at higher elevations. 4. Synthesis and applications. Management objectives are more likely to be met in high-elevation or precipitation locations where establishment of perennial grasses occurred. On lower and drier sites, management objectives are unlikely to be met with seeding alone

  4. Long Term Trend Analysis in the Capital Market – The Case of Serbia

    Directory of Open Access Journals (Sweden)

    Radukić Snežana

    2014-09-01

    Full Text Available The paper explores the possibility of making investment decisions in emerging markets by using the trend analysis method on a particular example of the capital market in Serbia. The authors, starting from the common features of technical analysis, have analysed the common share index value in the capital market in Serbia, in the Belgrade Stock Exchange - Belexline from 1 March 2006 to 31 March 2009, by the usage of two moving averages method - Moving Average Convergence Divergence (MACD: an intermediate term of 50 days and a long-term one of 100 days. The above mentioned moving averages identify the establishment of a trend, the cessation of the existing one, a change and an establishment of the new one.

  5. Are Remotely Sensed Trends in the Built Environment and Urban Vegetation Predictive of Changes in Metropolitan Housing Markets?

    Science.gov (United States)

    Endsley, K. A.

    2017-12-01

    In the midst of a global urbanization trend, residential neighborhoods are undergoing a variety of changes, including neighborhood turnover, the re-location of employment centers, and, recently, the increasing social and economic isolation of the suburbs. In the U.S., where residential lawns account for more area than any other irrigated crop (Polsky et al. 2014, in PNAS), coeval changes in residential populations, the built environment, and vegetation have serious implications for urban sustainability. To date, detailed studies of dynamic neighborhood changes have been hampered by the lack of fine time-series data on neighborhood composition. Most notably, the U.S. Census is conducted only once every decade leading to the likely inaccurate assumption of linear change between Census years. To the extent that human activities alter the built environment and urban ecology, can remotely sensed biophysical changes serve as a good proxy for neighborhood socio-economic changes? In this study, I apply time series data on spectral reflectance, spectral indices, and land-cover abundances from 15-to-25 years of Landsat data to fine-scale data on residential property transactions in two metropolitan areas with different regional economic and environmental contexts: Detroit and Los Angeles. The real estate record provides parcel-level, monthly data on sale prices and tax foreclosures; taken together, these provide a good description of the housing market and an acceptable proxy for neighborhood stability. By comparing lagged features from the remote sensing (RS) archive at different time scales in a non-parametric statistical learning algorithm, I identify which RS features best predict changes in the housing market and compare these associations between the two metropolitan areas and across multiple spatial and temporal scales along an urban to peri-urban gradient.

  6. Long-term trends in the ionosphere and upper atmosphere parameters

    Czech Academy of Sciences Publication Activity Database

    Bremer, J.; Alfonsi, L.; Pal, B.; Laštovička, Jan; Mikhailov, A. V.; Rogers, N.

    47 /suppl./, 2/3 (2004), s. 1009-1029 ISSN 1593-5213. [Final Meeting COST271 Action. Effects of the upper atmosphere on terrestrial and Earth-space communications (EACOS). Abingdon, 26.08.2004-27.08.2004] R&D Projects: GA MŠk OC 271.10 Institutional research plan: CEZ:AV0Z3042911 Keywords : long-term trends * ionosphere * upper atmosphere Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 0.413, year: 2004

  7. Photovoltaic System Pricing Trends. Historical, Recent, and Near-Term Projections, 2015 Edition

    Energy Technology Data Exchange (ETDEWEB)

    Feldman, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Margolis, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chung, Donald [National Renewable Energy Lab. (NREL), Golden, CO (United States); Fu, Ran [National Renewable Energy Lab. (NREL), Golden, CO (United States); Seel, Joachim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davidson, Carolyn [National Renewable Energy Lab. (NREL), Golden, CO (United States); Darghouth, Naïm [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-08-25

    This presentation, based on research at Lawrence Berkeley National Laboratory and the National Renewable Energy Laboratory, provides a high-level overview of historical, recent, and projected near-term PV pricing trends in the United States focusing on the installed price of PV systems. It also attempts to provide clarity surrounding the wide variety of potentially conflicting data available about PV system prices. This PowerPoint is the fourth edition from this series.

  8. Long-term trends in the northern extratropical ozone laminae with focus on European stations

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Križan, Peter; Kozubek, Michal

    2014-01-01

    Roč. 120, December (2014), s. 88-95 ISSN 1364-6826 R&D Projects: GA MŠk LD12070; GA ČR GAP209/10/1792 Institutional support: RVO:68378289 Keywords : ozone laminae * long-term trends * atmospheric dynamics Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.474, year: 2014 http://www.sciencedirect.com/science/article/pii/S1364682614002119

  9. Long-term surface pCO2 trends from observations and models

    International Nuclear Information System (INIS)

    Tjiputra, Jerry F.; Olsen, Are; Heinze, Christoph; Bopp, Laurent; Roy, Tilla

    2014-01-01

    We estimate regional long-term surface ocean pCO 2 growth rates using all available underway and bottled biogeochemistry data collected over the past four decades. These observed regional trends are compared with those simulated by five state-of-the-art Earth system models over the historical period. Oceanic pCO 2 growth rates faster than the atmospheric growth rates indicate decreasing atmospheric CO 2 uptake, while ocean pCO 2 growth rates slower than the atmospheric growth rates indicate increasing atmospheric CO 2 uptake. Aside from the western sub-polar North Pacific and the subtropical North Atlantic, our analysis indicates that the current observation-based basin-scale trends may be underestimated, indicating that more observations are needed to determine the trends in these regions. Encouragingly, good agreement between the simulated and observed pCO 2 trends is found when the simulated fields are sub sampled with the observational coverage. In agreement with observations, we see that the simulated pCO 2 trends are primarily associated with the increase in surface dissolved inorganic carbon (DIC) associated with atmospheric carbon uptake, and in part by warming of the sea surface. Under the RCP8.5 future scenario, DIC continues to be the dominant driver of pCO 2 trends, with little change in the relative contribution of SST. However, the changes in the hydrological cycle play an increasingly important role. For the contemporary (1970-2011) period, the simulated regional pCO 2 trends are lower than the atmospheric growth rate over 90% of the ocean. However, by year 2100 more than 40% of the surface ocean area has a higher oceanic pCO 2 trend than the atmosphere, implying a reduction in the atmospheric CO 2 uptake rate. The fastest pCO 2 growth rates are projected for the sub-polar North Atlantic, while the high-latitude Southern Ocean and eastern equatorial Pacific have the weakest growth rates, remaining below the atmospheric pCO 2 growth rate. Our work

  10. Long-term surface pCO2 trends from observations and models

    Directory of Open Access Journals (Sweden)

    Jerry F. Tjiputra

    2014-05-01

    Full Text Available We estimate regional long-term surface ocean pCO2 growth rates using all available underway and bottled biogeochemistry data collected over the past four decades. These observed regional trends are compared with those simulated by five state-of-the-art Earth system models over the historical period. Oceanic pCO2 growth rates faster than the atmospheric growth rates indicate decreasing atmospheric CO2 uptake, while ocean pCO2 growth rates slower than the atmospheric growth rates indicate increasing atmospheric CO2 uptake. Aside from the western subpolar North Pacific and the subtropical North Atlantic, our analysis indicates that the current observation-based basin-scale trends may be underestimated, indicating that more observations are needed to determine the trends in these regions. Encouragingly, good agreement between the simulated and observed pCO2 trends is found when the simulated fields are subsampled with the observational coverage. In agreement with observations, we see that the simulated pCO2 trends are primarily associated with the increase in surface dissolved inorganic carbon (DIC associated with atmospheric carbon uptake, and in part by warming of the sea surface. Under the RCP8.5 future scenario, DIC continues to be the dominant driver of pCO2 trends, with little change in the relative contribution of SST. However, the changes in the hydrological cycle play an increasingly important role. For the contemporary (1970–2011 period, the simulated regional pCO2 trends are lower than the atmospheric growth rate over 90% of the ocean. However, by year 2100 more than 40% of the surface ocean area has a higher oceanic pCO2 trend than the atmosphere, implying a reduction in the atmospheric CO2 uptake rate. The fastest pCO2 growth rates are projected for the subpolar North Atlantic, while the high-latitude Southern Ocean and eastern equatorial Pacific have the weakest growth rates, remaining below the atmospheric pCO2 growth rate. Our work

  11. Functional Trait Changes, Productivity Shifts and Vegetation Stability in Mountain Grasslands during a Short-Term Warming.

    Science.gov (United States)

    Debouk, Haifa; de Bello, Francesco; Sebastià, Maria-Teresa

    2015-01-01

    Plant functional traits underlie vegetation responses to environmental changes such as global warming, and consequently influence ecosystem processes. While most of the existing studies focus on the effect of warming only on species diversity and productivity, we further investigated (i) how the structure of community plant functional traits in temperate grasslands respond to experimental warming, and (ii) whether species and functional diversity contribute to a greater stability of grasslands, in terms of vegetation composition and productivity. Intact vegetation turves were extracted from temperate subalpine grassland (highland) in the Eastern Pyrenees and transplanted into a warm continental, experimental site in Lleida, in Western Catalonia (lowland). The impacts of simulated warming on plant production and diversity, functional trait structure, and vegetation compositional stability were assessed. We observed an increase in biomass and a reduction in species and functional diversity under short-term warming. The functional structure of the grassland communities changed significantly, in terms of functional diversity and community-weighted means (CWM) for several traits. Acquisitive and fast-growing species with higher SLA, early flowering, erect growth habit, and rhizomatous strategy became dominant in the lowland. Productivity was significantly positively related to species, and to a lower extent, functional diversity, but productivity and stability after warming were more dependent on trait composition (CWM) than on diversity. The turves with more acquisitive species before warming changed less in composition after warming. Results suggest that (i) the short-term warming can lead to the dominance of acquisitive fast growing species over conservative species, thus reducing species richness, and (ii) the functional traits structure in grassland communities had a greater influence on the productivity and stability of the community under short-term warming

  12. Functional Trait Changes, Productivity Shifts and Vegetation Stability in Mountain Grasslands during a Short-Term Warming.

    Directory of Open Access Journals (Sweden)

    Haifa Debouk

    Full Text Available Plant functional traits underlie vegetation responses to environmental changes such as global warming, and consequently influence ecosystem processes. While most of the existing studies focus on the effect of warming only on species diversity and productivity, we further investigated (i how the structure of community plant functional traits in temperate grasslands respond to experimental warming, and (ii whether species and functional diversity contribute to a greater stability of grasslands, in terms of vegetation composition and productivity. Intact vegetation turves were extracted from temperate subalpine grassland (highland in the Eastern Pyrenees and transplanted into a warm continental, experimental site in Lleida, in Western Catalonia (lowland. The impacts of simulated warming on plant production and diversity, functional trait structure, and vegetation compositional stability were assessed. We observed an increase in biomass and a reduction in species and functional diversity under short-term warming. The functional structure of the grassland communities changed significantly, in terms of functional diversity and community-weighted means (CWM for several traits. Acquisitive and fast-growing species with higher SLA, early flowering, erect growth habit, and rhizomatous strategy became dominant in the lowland. Productivity was significantly positively related to species, and to a lower extent, functional diversity, but productivity and stability after warming were more dependent on trait composition (CWM than on diversity. The turves with more acquisitive species before warming changed less in composition after warming. Results suggest that (i the short-term warming can lead to the dominance of acquisitive fast growing species over conservative species, thus reducing species richness, and (ii the functional traits structure in grassland communities had a greater influence on the productivity and stability of the community under short-term

  13. Importance of considering riparian vegetation requirements for the long-term efficiency of environmental flows in aquatic microhabitats

    Directory of Open Access Journals (Sweden)

    R. Rivaes

    2017-11-01

    Full Text Available Environmental flows remain biased toward the traditional biological group of fish species. Consequently, these flows ignore the inter-annual flow variability that rules species with longer lifecycles and therefore disregard the long-term perspective of the riverine ecosystem. We analyzed the importance of considering riparian requirements for the long-term efficiency of environmental flows. For that analysis, we modeled the riparian vegetation development for a decade facing different environmental flows in two case studies. Next, we assessed the corresponding fish habitat availability of three common fish species in each of the resulting riparian landscape scenarios. Modeling results demonstrated that the environmental flows disregarding riparian vegetation requirements promoted riparian degradation, particularly vegetation encroachment. Such circumstance altered the hydraulic characteristics of the river channel where flow depths and velocities underwent local changes of up to 10 cm and 40 cm s−1, respectively. Accordingly, after a decade of this flow regime, the available habitat area for the considered fish species experienced modifications of up to 110 % when compared to the natural habitat. In turn, environmental flows regarding riparian vegetation requirements were able to maintain riparian vegetation near natural standards, thereby preserving the hydraulic characteristics of the river channel and sustaining the fish habitat close to the natural condition. As a result, fish habitat availability never changed more than 17 % from the natural habitat.

  14. Trends in All-Cause Mortality across Gestational Age in Days for Children Born at Term

    DEFF Research Database (Denmark)

    Wu, Chunsen; Sun, Yuelian; Nohr, Ellen Aagaard

    2015-01-01

    pattern was observed when analyses were restricted to children born to by mothers without pregnancy complications. CONCLUSIONS: This study demonstrates heterogeneity in mortality rates even among singletons born at term. The highest mortality was observed among children born 37 weeks of gestation, which......BACKGROUND: Term birth is a gestational age from 259 days to 293 days. However trends in mortality according to gestational ages in days have not yet been described in this time period. METHODS AND FINDINGS: Based on nation-wide registries, we conducted a population-based cohort study among all...... children born at term in Denmark from 1997 to 2004 to estimate differences in mortality across gestational ages in days among singletons born at term. We studied early-neonatal mortality, neonatal mortality, infant mortality, and five-year mortality. Children were followed from birth up to the last day...

  15. Trend analysis of evapotranspiration over India: Observed from long-term satellite measurements

    Science.gov (United States)

    Goroshi, Sheshakumar; Pradhan, Rohit; Singh, Raghavendra P.; Singh, K. K.; Parihar, Jai Singh

    2017-12-01

    Owing to the lack of consistent spatial time series data on actual evapotranspiration ( ET), very few studies have been conducted on the long-term trend and variability in ET at a national scale over the Indian subcontinent. The present study uses biome specific ET data derived from NOAA satellite's advanced very high resolution radiometer to investigate the trends and variability in ET over India from 1983 to 2006. Trend analysis using the non-parametric Mann-Kendall test showed that the domain average ET decreased during the period at a rate of 0.22 mm year^{-1}. A strong decreasing trend (m = -1.75 mm year^{-1}, F = 17.41, P 0.01) was observed in forest regions. Seasonal analyses indicated a decreasing trend during southwest summer monsoon (m= -0.320 mm season^{-1} year^{-1}) and post-monsoon period (m= -0.188 mm season^{-1 } year^{-1}). In contrast, an increasing trend was observed during northeast winter monsoon (m = 0.156 mm season^{-1 } year^{-1}) and pre-monsoon (m = 0.068 mm season^{-1 } year^{-1}) periods. Despite an overall net decline in the country, a considerable increase ( 4 mm year^{-1}) was observed over arid and semi-arid regions. Grid level correlation with various climatic parameters exhibited a strong positive correlation (r >0.5) of ET with soil moisture and precipitation over semi-arid and arid regions, whereas a negative correlation (r -0.5) occurred with temperature and insolation in dry regions of western India. The results of this analysis are useful for understanding regional ET dynamics and its relationship with various climatic parameters over India. Future studies on the effects of ET changes on the hydrological cycle, carbon cycle, and energy partitioning are needed to account for the feedbacks to the climate.

  16. How consistent are global long-term satellite LAI products in terms of interannual variability and trend?

    Science.gov (United States)

    Jiang, C.; Ryu, Y.; Fang, H.

    2016-12-01

    Proper usage of global satellite LAI products requires comprehensive evaluation. To address this issue, the Committee on Earth Observation Satellites (CEOS) Land Product Validation (LPV) subgroup proposed a four-stage validation hierarchy. During the past decade, great efforts have been made following this validation framework, mainly focused on absolute magnitude, seasonal trajectory, and spatial pattern of those global satellite LAI products. However, interannual variability and trends of global satellite LAI products have been investigated marginally. Targeting on this gap, we made an intercomparison between seven global satellite LAI datasets, including four short-term ones: MODIS C5, MODIS C6, GEOV1, MERIS, and three long-term products ones: LAI3g, GLASS, and GLOBMAP. We calculated global annual LAI time series for each dataset, among which we found substantial differences. During the overlapped period (2003 - 2011), MODIS C5, GLASS and GLOBMAP have positive correlation (r > 0.6) between each other, while MODIS C6, GEOV1, MERIS, and LAI3g are highly consistent (r > 0.7) in interannual variations. However, the previous three datasets show negative trends, all of which use MODIS C5 reflectance data, whereas the latter four show positive trends, using MODIS C6, SPOT/VGT, ENVISAT/MERIS, and NOAA/AVHRR, respectively. During the pre-MODIS era (1982 - 1999), the three AVHRR-based datasets (LAI3g, GLASS and GLOBMAP) agree well (r > 0.7), yet all of them show oscillation related with NOAA platform changes. In addition, both GLASS and GLOBMAP show clear cut-points around 2000 when they move from AVHRR to MODIS. Such inconsistency is also visible for GEOV1, which uses SPOT-4 and SPOT-5 before and after 2002. We further investigate the map-to-map deviations among these products. This study highlights that continuous sensor calibration and cross calibration are essential to obtain reliable global LAI time series.

  17. Decreasing Trend in the Use and Long-Term Use of Benzodiazepines Among Young Adults.

    Science.gov (United States)

    Tähkäpää, Sanna-Mari; Saastamoinen, Leena; Airaksinen, Marja; Tuulio-Henriksson, Annamari; Aalto-Setälä, Terhi; Kurko, Terhi

    2018-03-14

    Patterns of benzodiazepine (BZD) use and long-term use among young adults are not well known. Our aim was to study trends in BZD use and long-term use among 18-25-year-old young adults by gender and active substance in a nationwide retrospective longitudinal register-based setting. All Finns aged 18-25 years with reimbursed purchases of BZDs in 2006-2014 recorded to the Finnish Prescription Register were included. Annual prevalence rates of BZD use and long-term use among young adults were reported overall, according to gender, drug group (anxiolytic or hypnotic), and active substance. Long-term use of BZDs was defined as purchasing ≥180 Defined Daily Doses (DDDs) in at least two drug purchases during a calendar year. Overall prevalence of BZD use among young adults decreased from 24.0 to 18.8 users per 1000 inhabitants in 2006-2014. Prevalence of long-term use decreased from 5.5 to 3.3 users per 1000 inhabitants. Overall BZD use was higher among females, whereas long-term use was more common among males. Use of anxiolytics was more common than use of hypnotics. Oxazepam, alprazolam, zopiclone, and zolpidem were the most used BZDs, whereas alprazolam and clonazepam were the substances with most long-term use. The use and long-term use of BZDs have decreased annually since 2008 among Finnish young adults. Further research is needed to investigate the reasons behind the decline.

  18. Identification of trend in long term precipitation and reference evapotranspiration over Narmada river basin (India)

    Science.gov (United States)

    Pandey, Brij Kishor; Khare, Deepak

    2018-02-01

    Precipitation and reference evapotranspiration are key parameters in hydro-meteorological studies and used for agricultural planning, irrigation system design and management. Precipitation and evaporative demand are expected to be alter under climate change and affect the sustainable development. In this article, spatial variability and temporal trend of precipitation and reference evapotranspiration (ETo) were investigated over Narmada river basin (India), a humid tropical climatic region. In the present study, 12 and 28 observatory stations were selected for precipitation and ETo, respectively of 102-years period (1901-2002). A rigorous analysis for trend detection was carried out using non parametric tests such as Mann-Kendall (MK) and Spearman Rho (SR). Sen's slope estimator was used to analyze the rate of change in long term series. Moreover, all the stations of basin exhibit positive trend for annual ETo, while 8% stations indicate significant negative trend for mean annual precipitation, respectively. Change points of annual precipitation were identified around the year 1962 applying Buishand's and Pettit's test. Annual mean precipitation reduced by 9% in upper part while increased maximum by 5% in lower part of the basin due temporal changes. Although annual mean ETo increase by 4-12% in most of the region. Moreover, results of the study are very helpful in planning and development of agricultural water resources.

  19. Do climate model predictions agree with long-term precipitation trends in the arid southwestern United States?

    Science.gov (United States)

    Elias, E.; Rango, A.; James, D.; Maxwell, C.; Anderson, J.; Abatzoglou, J. T.

    2016-12-01

    Researchers evaluating climate projections across southwestern North America observed a decreasing precipitation trend. Aridification was most pronounced in the cold (non-monsoonal) season, whereas downward trends in precipitation were smaller in the warm (monsoonal) season. In this region, based upon a multimodel mean of 20 Coupled Model Intercomparison Project 5 models using a business-as-usual (Representative Concentration Pathway 8.5) trajectory, midcentury precipitation is projected to increase slightly during the monsoonal time period (July-September; 6%) and decrease slightly during the remainder of the year (October-June; -4%). We use observed long-term (1915-2015) monthly precipitation records from 16 weather stations to investigate how well measured trends corroborate climate model predictions during the monsoonal and non-monsoonal timeframe. Running trend analysis using the Mann-Kendall test for 15 to 101 year moving windows reveals that half the stations showed significant (p≤0.1), albeit small, increasing trends based on the longest term record. Trends based on shorter-term records reveal a period of significant precipitation decline at all stations representing the 1950s drought. Trends from 1930 to 2015 reveal significant annual, monsoonal and non-monsoonal increases in precipitation (Fig 1). The 1960 to 2015 time window shows no significant precipitation trends. The more recent time window (1980 to 2015) shows a slight, but not significant, increase in monsoonal precipitation and a larger, significant decline in non-monsoonal precipitation. GCM precipitation projections are consistent with more recent trends for the region. Running trends from the most recent time window (mid-1990s to 2015) at all stations show increasing monsoonal precipitation and decreasing Oct-Jun precipitation, with significant trends at 6 of 16 stations. Running trend analysis revealed that the long-term trends were not persistent throughout the series length, but depended

  20. Long-term dynamics of OH * temperatures over central Europe: trends and solar correlations

    Directory of Open Access Journals (Sweden)

    C. Kalicinsky

    2016-12-01

    Full Text Available We present the analysis of annual average OH* temperatures in the mesopause region derived from measurements of the Ground-based Infrared P-branch Spectrometer (GRIPS at Wuppertal (51° N, 7° E in the time interval 1988 to 2015. The new study uses a temperature time series which is 7 years longer than that used for the latest analysis regarding the long-term dynamics. This additional observation time leads to a change in characterisation of the observed long-term dynamics. We perform a multiple linear regression using the solar radio flux F10.7 cm (11-year cycle of solar activity and time to describe the temperature evolution. The analysis leads to a linear trend of (−0.089 ± 0.055 K year−1 and a sensitivity to the solar activity of (4.2 ± 0.9 K (100 SFU−1 (r2 of fit 0.6. However, one linear trend in combination with the 11-year solar cycle is not sufficient to explain all observed long-term dynamics. In fact, we find a clear trend break in the temperature time series in the middle of 2008. Before this break point there is an explicit negative linear trend of (−0.24 ± 0.07 K year−1, and after 2008 the linear trend turns positive with a value of (0.64 ± 0.33 K year−1. This apparent trend break can also be described using a long periodic oscillation. One possibility is to use the 22-year solar cycle that describes the reversal of the solar magnetic field (Hale cycle. A multiple linear regression using the solar radio flux and the solar polar magnetic field as parameters leads to the regression coefficients Csolar = (5.0 ± 0.7 K (100 SFU−1 and Chale = (1.8 ±  0.5 K (100 µT−1 (r2 = 0.71. The second way of describing the OH* temperature time series is to use the solar radio flux and an oscillation. A least-square fit leads to a sensitivity to the solar activity of (4.1 ± 0.8 K (100 SFU−1, a period P  =  (24.8 ± 3.3 years, and

  1. Long-Term Trends in Hematological and Nutritional Status After Gastrectomy for Gastric Cancer.

    Science.gov (United States)

    Kim, Ji-Hyun; Bae, You-Jin; Jun, Kyong-Hwa; Chin, Hyung-Min

    2017-08-01

    This study investigated long-term trends in hematological and nutritional parameters after gastrectomy for gastric cancer and evaluated the influence of the reconstruction type on these trends. The medical records of 558 patients who underwent curative gastrectomy with standard lymph node dissection for stage I gastric cancer between January 2006 and December 2013 were reviewed. The hematological and nutritional parameters evaluated included hemoglobin, ferritin, vitamin B 12 , total protein, albumin, total cholesterol, triglyceride, and calcium. The patients were followed up for 6 months postoperatively and then annually until death, cancer recurrence, or follow-up loss. In the long term, ferritin and triglyceride gradually decreased after gastrectomy, while the other parameters decreased slightly or were stable. In the comparisons according to reconstruction type, the Roux-en-Y group had the lowest levels of hemoglobin, ferritin, vitamin B12, total protein, albumin, and total cholesterol beginning 6 months postoperatively compared with the Billroth I and II groups. However, only ferritin and vitamin B 12 had significant differences in the 5-year cumulative incidences of deficiency/reduction according to the reconstruction type, whereas albumin, triglyceride, total cholesterol, and calcium did not. Although malabsorption and malnutrition are common in patients after a gastrectomy, most nutritional parameters were stable or decreased slightly in the long-term and were not markedly influenced by the reconstruction type or extent of gastrectomy. Therefore, for more accurate nutritional assessment after gastrectomy, multidirectional monitoring should be considered rather than simply measuring biochemical parameters.

  2. Long-term trends in foF2: their estimating and origin

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Yue, X.; Wan, W.

    2008-01-01

    Roč. 26, č. 3 (2008), s. 593-598 ISSN 0992-7689 R&D Projects: GA MŠk OC 091 Grant - others:COST(XE) 296; National Science Foundation of China(CN) 40636032; National Science Foundation of China(CN) 40574071; National important Basic Research Project(CN) 2006CB806306 Institutional research plan: CEZ:AV0Z30420517 Keywords : ionosphere * long-term trends * geomagnetism and paleomagnetism * Radio Science Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.660, year: 2008 http://www.ann-geophys.net/26/593/2008/

  3. Northern Hemisphere stratospheric winds in higher midlatitudes: longitudinal distribution and long-term trends

    Czech Academy of Sciences Publication Activity Database

    Kozubek, Michal; Križan, Peter; Laštovička, Jan

    2015-01-01

    Roč. 15, Feb (2015), s. 2203-2213 ISSN 1680-7316 R&D Projects: GA ČR GAP209/10/1792; GA ČR GA15-03909S; GA MŠk LD12070 Institutional support: RVO:68378289 Keywords : stratospheric dynamics * meridional wind * long-term trend Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 5.114, year: 2015 http://www.atmos-chem-phys.net/15/2203/2015/acp-15-2203-2015.html

  4. Long-Term Energy Trends – Where Will We Be in 2050?

    OpenAIRE

    DIAZ-RAINEY, Ivan

    2009-01-01

    4TH ENERDAY CONFERENCE ON ENERGY ECONOMICS AND TECHNOLOGY, TU DRESDEN APRIL 3RD, 2009 The fourth gathering of the popular ENERDAY Conference was a one day event guided by the giddy-sounding theme of “LONG-TERM ENERGY TRENDS – WHERE WILL WE BE IN 2050?” The event attracted over 90 European experts in energy policy, energy technology and energy economics from academia, regulators, consultancies, and the energy industry itself. The event took place under the umbrella of TU Dres...

  5. MORTALITY TRENDS FOR MOST COMMON TYPES OF CANCER IN SILESIA VOIVODESHIP IN SHORT TERM PROJECTION

    Directory of Open Access Journals (Sweden)

    Brunon Zemła

    2011-06-01

    Full Text Available Background: The incidence of morbidity and mortality of cancers rapidly increase in the world and so it is in case of Poland and Silesia Voivodeship. Therefore an attempt is made to assess this phenomenon in projection scale within Silesia Voivodeship. Materials and methods: The time-trends analysis of the six most common types of cancer have been selected: stomach, colorectal, pancreas and lung (among both genders, prostate (among males and breast (among females. For the period 1990–2008 age standardized mortality rates have been determined. Time-trends in mortality with employment of joinpoint regression have been estimated and depending on trends linear or log-linear regression models were used which set up the base for short-term projection. Results: For the year 2018 projection values of mortality rates among males will drop (with the exception of lung and colorectal cancers. For prostate cancer – the values will be increasing. Among females stomach mortality rates will drop, but again lung cancer mortality rate will double in comparison to data for 1990. Conclusions: 1. The prognostic number of death to 2018 year concern all studied cancer increasing, for exept stomach cancer. 2. Especially will be increasing cancer mortality standardized rates for lung cancer among females and prostate and colorectal cancers among males.

  6. NAEP 1999 Long-Term Trend Technical Analysis Report: Three Decades of Student Performance. NCES 2005-484

    Science.gov (United States)

    Allen, Nancy L.; McClellan, Catherine A.; Stoeckel, Joan J.

    2005-01-01

    This report provides an update to the technical analysis procedures documenting the 1996 National Assessment of Educational Progress (NAEP) as presented in "The NAEP 1996 Technical Report" (Allen, Carlson, and Zelenak, 1999). It describes how the 1999 long-term trend data were incorporated into the trend analyses. Since no national main…

  7. Long-term trends of men's co-residence with children in England and Wales

    Directory of Open Access Journals (Sweden)

    Ursula Henz

    2014-03-01

    Full Text Available Background: Increasing numbers of childless men as well as fathers with reduced or no contact with their children have sparked concern about an erosion of fatherhood. Although the general trend is undisputed, claims about men's decreasing family involvement lack a sound empirical basis that enables comparisons between countries and sub-groups of society. Objective: This study derives long-term trends in father-child co-residence over the life course in England and Wales, and provides comparisons of these trends by level of education and ethnic origin. Methods: The paper calculates shares of father-child co-residence from the National Statistics Longitudinal Study (LS and the British Labour-Force Surveys (LFS. Results: There has been a decline of father-child co-residence in England and Wales for men in their thirties, an even greater decline for men in their twenties, and a small increase in the shares of father-child co-residence at higher ages. The trends for different educational groups were similar, but men with a degree had particularly low rates of father-child co-residence at younger ages, and relatively high ones at older ages. Neither less-educated men, nor men from Black-Caribbean and Black-African origins showed rates of father-child co-residence as low as one might have expected. Conclusions: The steady decline of father-child co-residence among men born between 1930 and 1979 in England and Wales lends support to claims about an erosion of fatherhood. However, it is unwarranted to generalize findings from other countries about particularly low levels of father-child co-residence among less-educated men to men in England and Wales.

  8. Long- and short-term trends in vessel conditioning of TFTR [Tokamak Fusion Test Reactor

    International Nuclear Information System (INIS)

    LaMarche, P.H.; Dylla, H.F.; Bell, M.G.

    1986-10-01

    We have investigated trends in the conditioning of the Tokamak Fusion Test Reactor (TFTR) vacuum vessel during the May 1984 to April 1985 run period. The initial conditioning of the vessel, consisting of glow discharge cleaning (GDC) and pulse discharge cleaning (PDC) in concert with a 150 0 C vessel bakeout, is necessary to assure plasma operation after atmospheric venting. A long-term conditioning process, ascribed to limiter conditioning, effectively improves operational conditions during the course of the run. Over several thousand high power plasma discharges, the improvement was documented by using standard parameter (fiducial) plasma discharges. Several techniques demonstrated short-term improvements in vessel conditioning during this time period, including: Cr gettering and programming the plasma position relative to the limiter contact area

  9. Long term trends in PBDE concentrations in gannet (Morus bassanus) eggs from two UK colonies

    International Nuclear Information System (INIS)

    Crosse, John D.; Shore, Richard F.; Jones, Kevin C.; Pereira, M. Glória

    2012-01-01

    We used the eggs of an avian sentinel, the Northern gannet (Morus bassanus), to determine long-term (1977–2007) trends in PBDE contamination in Western Atlantic (Ailsa Craig colony) and North Sea (Bass Rock colony) waters around the UK. BDEs 47, 49, 99, 100, 153, 154 were the most abundant and were found in all eggs. Individual congener and ΣPBDE concentrations in eggs from both colonies increased mainly from the late 1980s, peaked in 1994, and then rapidly declined so that concentrations in 2002 were similar to or lower than those in the 1970s and 1980s. The PBDE congener profile and temporal variation in PBDE concentrations suggests that the Penta-BDE technical formula was the main source of PBDE contamination. However, contributions of heavier BDE congeners to ΣPBDE concentrations have increased over time, suggesting other sources are becoming more important. PBDEs had no measurable effect on egg volume or eggshell index. - Highlights: ► Detailed long-term (1977–2007) PBDE trends are presented in gannet eggs from the UK. ► Temporal trends mirror consumption of PeBDE technical products. ► In recent years the PBDE profile heavier BDEs became increasingly more important. ► BDE35 concentrations decreased linearly throughout the monitoring period. ► ΣPBDE levels in gannet eggs are below levels linked to impaired reproductive output. - PBDE levels in gannet eggs from two UK colonies mirrored patterns of PBDE consumption, but sources other than PeBDE became more prevalent in recent years.

  10. Nitrogen Dioxide long term trends at mid and high latitudes by means of ground based observations

    Science.gov (United States)

    Bortoli, D.; Petritoli, A.; Giovanelli, G.; Kostadinov, I.; Ravegnani, F.

    2003-04-01

    The interactions between mid- and high latitudes atmospheric changes are going to be one of the main issue for the future of stratospheric and tropospheric chemistry research. A more detailed study of the ozone trends as well as a wider comprehension of the interactions with lower and higher latitudes are maybe the main arguments to which scientist should address their works in order to build-up a more detailed picture of what scenarios we have to face in the near future. GASCODs type spectrometers (Gas Analyzer Spectrometer Correlating Optical Differences) are installed at the "Ottavio Vittori" research station (44.11N, 10.42E, 2165 m asl) since June 1993, at the Italian Antarctic Station (74.69S, 164.12E) since December 1995 and at the STIL-BAS station (42.42N, 25.63E) since 1999. The instruments measure zenith scattered solar radiation between 407 and 464 nm. Nitrogen dioxide total column is retrieved with DOAS methodology. The seasonal trend of NO2 vc values is reported and it shows the expected behaviour: maximum values during the summer period while the minimum occur in the winter season in both the hemispheres. A typical behaviour of the AMPM ratio at high latitudes is highlight. A Fourier analysis is proposed as a tool to investigate the long-term components of nitrogen dioxide stratospheric amount. Results are presented and the NO2 trend is evidenced and commented. ACKNOWLEDGMENTS: The author Daniele Bortoli was financially supported by the Subprograma Ciência e Tecnologia do 3° Quadro Comunitário de Apoio. The National Antarctic Research Program (PNRA) and the Quantification and Interpretation of Long-Term UV-Vis Observations of the Stratosphere (QUILT) project supported this research.

  11. Volcanic ash deposition and long-term vegetation change on Subantarctic Marion Island

    NARCIS (Netherlands)

    Yeloff, D.; Mauquoy, D.S.; Barber, K.; Way, S.; van Geel, B.; Turney, C.S.M.

    2007-01-01

    A c. 5500 year record of peatland development and vegetation change was generated from a core recovered from an Agrostis magellanica peat bog on subantarctic Marion Island, using palynomorph, plant macrofossil, and tephra analyses. Two tephra horizons (both 17 cm thick) were identified and dated to

  12. The Interval Slope Method for Long-Term Forecasting of Stock Price Trends

    Directory of Open Access Journals (Sweden)

    Chun-xue Nie

    2016-01-01

    Full Text Available A stock price is a typical but complex type of time series data. We used the effective prediction of long-term time series data to schedule an investment strategy and obtain higher profit. Due to economic, environmental, and other factors, it is very difficult to obtain a precise long-term stock price prediction. The exponentially segmented pattern (ESP is introduced here and used to predict the fluctuation of different stock data over five future prediction intervals. The new feature of stock pricing during the subinterval, named the interval slope, can characterize fluctuations in stock price over specific periods. The cumulative distribution function (CDF of MSE was compared to those of MMSE-BC and SVR. We concluded that the interval slope developed here can capture more complex dynamics of stock price trends. The mean stock price can then be predicted over specific time intervals relatively accurately, in which multiple mean values over time intervals are used to express the time series in the long term. In this way, the prediction of long-term stock price can be more precise and prevent the development of cumulative errors.

  13. Detecting robust signals of interannual variability of gross primary productivity in Asia from multiple terrestrial carbon cycle models and long-term satellite-based vegetation data

    Science.gov (United States)

    Ichii, K.; Kondo, M.; Ueyama, M.; Kato, T.; Ito, A.; Sasai, T.; Sato, H.; Kobayashi, H.; Saigusa, N.

    2014-12-01

    Long term record of satellite-based terrestrial vegetation are important to evaluate terrestrial carbon cycle models. In this study, we demonstrate how multiple satellite observation can be used for evaluating past changes in gross primary productivity (GPP) and detecting robust anomalies in terrestrial carbon cycle in Asia through our model-data synthesis analysis, Asia-MIP. We focused on the two different temporal coverages: long-term (30 years; 1982-2011) and decadal (10 years; 2001-2011; data intensive period) scales. We used a NOAA/AVHRR NDVI record for long-term analysis and multiple satellite data and products (e.g. Terra-MODIS, SPOT-VEGETATION) as historical satellite data, and multiple terrestrial carbon cycle models (e.g. BEAMS, Biome-BGC, ORCHIDEE, SEIB-DGVM, and VISIT). As a results of long-term (30 years) trend analysis, satellite-based time-series data showed that approximately 40% of the area has experienced a significant increase in the NDVI, while only a few areas have experienced a significant decreasing trend over the last 30 years. The increases in the NDVI were dominant in the sub-continental regions of Siberia, East Asia, and India. Simulations using the terrestrial biosphere models also showed significant increases in GPP, similar to the results for the NDVI, in boreal and temperate regions. A modeled sensitivity analysis showed that the increases in GPP are explained by increased temperature and precipitation in Siberia. Precipitation, solar radiation, CO2fertilization and land cover changes are important factors in the tropical regions. However, the relative contributions of each factor to GPP changes are different among the models. Year-to-year variations of terrestrial GPP were overall consistently captured by the satellite data and terrestrial carbon cycle models if the anomalies are large (e.g. 2003 summer GPP anomalies in East Asia and 2002 spring GPP anomalies in mid to high latitudes). The behind mechanisms can be consistently

  14. Long-term trend and variability of atmospheric PM10 concentration in the Po Valley

    Science.gov (United States)

    Bigi, A.; Ghermandi, G.

    2014-05-01

    The limits to atmospheric pollutant concentration set by the European Commission provide a challenging target for the municipalities in the Po Valley, because of the characteristic climatic conditions and high population density of this region. In order to assess climatology and trends in the concentration of atmospheric particles in the Po Valley, a data set of PM10 data from 41 sites across the Po Valley have been analysed, including both traffic and background sites (either urban, suburban or rural). Of these 41 sites, 18 with 10 yr or longer record have been analysed for long-term trend in deseasonalized monthly means, in annual quantiles and in monthly frequency distribution. A widespread significant decreasing trend has been observed at most sites, up to a few percent per year, by a generalized least squares and Theil-Sen method. All 41 sites have been tested for significant weekly periodicity by Kruskal-Wallis test for mean anomalies and by Wilcoxon test for weekend effect magnitude. A significant weekly periodicity has been observed for most PM10 series, particularly in summer and ascribed mainly to anthropic particulate emissions. A cluster analysis has been applied in order to highlight stations sharing similar pollution conditions over the reference period. Five clusters have been found, two encompassing the metropolitan areas of Turin and Milan and their respective nearby sites and the other three clusters gathering northeast, northwest and central Po Valley sites respectively. Finally, the observed trends in atmospheric PM10 have been compared to trends in provincial emissions of particulates and PM precursors, and analysed along with data on vehicular fleet age, composition and fuel sales. A significant basin-wide drop in emissions occurred for gaseous pollutants, contrarily to emissions of PM10 and PM2.5, whose drop was low and restricted to a few provinces. It is not clear whether the decrease for only gaseous emissions is sufficient to explain the

  15. Assessment of short- and long-term memory in trends of major climatic variables over Iran: 1966-2015

    Science.gov (United States)

    Mianabadi, Ameneh; Shirazi, Pooya; Ghahraman, Bijan; Coenders-Gerrits, A. M. J.; Alizadeh, Amin; Davary, Kamran

    2018-02-01

    In arid and semi-arid regions, water scarcity is the crucial issue for crop production. Identifying the spatial and temporal trends in aridity, especially during the crop-growing season, is important for farmers to manage their agricultural practices. This will become especially relevant when considering climate change projections. To reliably determine the actual trends, the influence of short- and long-term memory should be removed from the trend analysis. The objective of this study is to investigate the effect of short- and long-term memory on estimates of trends in two aridity indicators—the inverted De Martonne (ϕ IDM ) and Budyko (ϕ B ) indices. The analysis is done using precipitation and temperature data over Iran for a 50-year period (1966-2015) at three temporal scales: annual, wheat-growing season (October-June), and maize-growing season (May-November). For this purpose, the original and the modified Mann-Kendall tests (i.e., modified by three methods of trend free pre-whitening (TFPT), effective sample size (ESS), and long-term persistence (LTP)) are used to investigate the temporal trends in aridity indices, precipitation, and temperature by taking into account the effect of short- and long-term memory. Precipitation and temperature data were provided by the Islamic Republic of Iran Meteorological Organization (IRIMO). The temporal trend analysis showed that aridity increased from 1966 to 2015 at the annual and wheat-growing season scales, which is due to a decreasing trend in precipitation and an increasing trend in mean temperature at these two timescales. The trend in aridity indices was decreasing in the maize-growing season, since precipitation has an increasing trend for most parts of Iran in that season. The increasing trend in aridity indices is significant in Western Iran, which can be related to the significantly more negative trend in precipitation in the West. This increasing trend in aridity could result in an increasing crop water

  16. Assessment of pest and pesticide trends in vegetable crops in united arab emirates and sultanate of oman

    International Nuclear Information System (INIS)

    Waakeh, W.; Aldahmani, J.H.; Deadman, M.L.; Saadi, A.A.

    2007-01-01

    A preliminary survey on pesticide uses in 40 vegetable-growing farms representing different agricultural areas in Oman and the UAE, twenty farms from each country, revealed that all the vegetable farms used pesticides for crop protection. Among the major insect-pests, white flies (Bemisia tabaci), leafminers (Liriomyza trifolii), melon fruit flies (Bactrocera ciliatus), aphids (Aphis spp.) and tobacco leafworm (Spodoptera litteralis) were recorded in Omani farms. In the UAE, white flies, leafminers, cutworms (Agrotis ypsilan), tomato fruitworms (Helicoverpa armigera) and eggplant fruitworms (Leucinodes orbonalis) were the 5 top insect-pests. Among the plant diseases, powdery mildew (Erysiphe spp.), blight (Alternaria spp.), damping off (Pythium spp.), leafspot (Alternaria spp.) and mosaic (CMV) Were major cause of vegetable diseases in Omani farms; whereas, damping off (Pythium aphanidermatum), downy mildew (Pseudoperonspora cubensis), early blight (Alternaria solani), septoria leaf spot (Septoria lycopersici) and anthracnose rip rot (colletotrichum spp.) were the most predominant diseases encountered in most UAE farms. Among the most commonly used pesticides, 29 insecticides, 16 fungicides and 3 herbicides were used by the vegetable farmers. Around 55% of Omani farms used routine application of pesticides, irrespective of the pest presence. Whereas, in the UAE, most farmers started to spray pesticides at 6-20% pest (insect, disease and weeds) infection. Over 65 of the farms, in both the countries, received chemical pest management information from the sales representatives. (author)

  17. Detecting Inter-Annual Variations in the Phenology of Evergreen Conifers Using Long-Term MODIS Vegetation Index Time Series

    Directory of Open Access Journals (Sweden)

    Laura Ulsig

    2017-01-01

    Full Text Available Long-term observations of vegetation phenology can be used to monitor the response of terrestrial ecosystems to climate change. Satellite remote sensing provides the most efficient means to observe phenological events through time series analysis of vegetation indices such as the Normalized Difference Vegetation Index (NDVI. This study investigates the potential of a Photochemical Reflectance Index (PRI, which has been linked to vegetation light use efficiency, to improve the accuracy of MODIS-based estimates of phenology in an evergreen conifer forest. Timings of the start and end of the growing season (SGS and EGS were derived from a 13-year-long time series of PRI and NDVI based on a MAIAC (multi-angle implementation of atmospheric correction processed MODIS dataset and standard MODIS NDVI product data. The derived dates were validated with phenology estimates from ground-based flux tower measurements of ecosystem productivity. Significant correlations were found between the MAIAC time series and ground-estimated SGS (R2 = 0.36–0.8, which is remarkable since previous studies have found it difficult to observe inter-annual phenological variations in evergreen vegetation from satellite data. The considerably noisier NDVI product could not accurately predict SGS, and EGS could not be derived successfully from any of the time series. While the strongest relationship overall was found between SGS derived from the ground data and PRI, MAIAC NDVI exhibited high correlations with SGS more consistently (R2 > 0.6 in all cases. The results suggest that PRI can serve as an effective indicator of spring seasonal transitions, however, additional work is necessary to confirm the relationships observed and to further explore the usefulness of MODIS PRI for detecting phenology.

  18. Long term operation of nuclear power plants – IAEA SALTO missions observations and trends

    Energy Technology Data Exchange (ETDEWEB)

    Krivanek, Robert, E-mail: r.krivanek@iaea.org [Operational Safety Section, Department of Nuclear Safety and Security, International Atomic Energy Agency (IAEA), Vienna 1400 (Austria); Havel, Radim, E-mail: Radim.Havel@gmail.com [RESCO, Nitranska 894/8, 10100 Praha 10 (Czech Republic)

    2016-08-15

    Highlights: • During the period 2005–mid 2015, 22 SALTO peer review missions and 2 LTO modules of OSART missions were conducted. • Analysis of these mission results and main trends observed are gathered in this paper. • The main task of the assessment performed was to evaluate and give a weight to the evaluation. • Results of SALTO follow-up missions as well as OSART follow-up missions with LTO module are summarized. • The SALTO peer review service is strongly recommended for NPPs prior to entering LTO period. - Abstract: This paper builds on paper “Long term operation of nuclear power plants – IAEA SALTO peer review service and its results”, NED8070, presented in Nuclear Engineering and Design in September 2014. This paper presents the analysis of SALTO mission results and main trends observed so that all the most important results of SALTO missions are gathered in one paper. The paper also includes the results of LTO module reviews performed in the frame of OSART missions where applicable as well as follow-up missions. This paper is divided in three main Sections. Section 1 provides brief introduction to SALTO peer review service. Section 2 provides overview of performed SALTO missions and LTO modules of OSART missions performed between 2005 and mid-2015. Section 3 summarizes the most significant observations and trends resulting from the missions between 2005 and mid-2015. Section 4 summarizes the results of SALTO follow-up missions as well as OSART follow-up missions.

  19. Long-term Trend and Fractal of Annual Runoff Process in Mainstream of Tarim River

    Institute of Scientific and Technical Information of China (English)

    XU Jianhua; CHEN Yaning; LI Weihong; DONG Shan

    2008-01-01

    Based on the time series data from the Aral hydrological station for the period of 1958-2005, the paper re-veals the long-term trend and fractal of the annual runoff process in the mainstream of the Tarim River by using thewavelet analysis method and the fractal theory. The main conclusions are as follows: 1) From a large time scale pointof view, i.e. the time scale of 16 (24) years, the annual runoff basically shows a slightly decreasing trend as a wholefrom 1958 to 2005. If the time scale is reduced to 8 (23) or 4 (22) years, the annual runoff still displays the basic trendas the large time scale, but it has fluctuated more obviously during the period. 2) The correlation dimension for theannual runoff process is 3.4307, non-integral, which indicates that the process has both fractal and chaotic characteris-tics. The correlation dimension is above 3, which means that at least four independent variables are needed to describethe dynamics of the annual runoff process. 3) The Hurst exponent for the first period (1958-1973) is 0.5036, whichequals 0.5 approximately and indicates that the annual runoff process is in chaos. The Hurst exponents for the second(1974-1989) and third (1990-2005) periods are both greater than 0.50, which indicate that the annual runoff processshowed a long-enduring characteristic in the two periods. The Hurst exponent for the period from 1990 to 2005 indi-cates that the annual runoffwill show a slightly increasing trend in the 16 years after 2005.

  20. Long-term sustainability of a worksite canteen intervention of serving more fruit and vegetables

    DEFF Research Database (Denmark)

    Thorsen, Anne Vibeke; Lassen, Anne Dahl; Tetens, Inge

    2010-01-01

    Objective: To analyse the 5-year sustainability of a worksite canteen intervention of serving more fruit and vegetables (F&V). Design: Average F&V consumption per customer per meal per day was assessed in five worksite canteens by weighing F&V served and subtracting waste. Data were collected by ...... where the participatory and empowering approach, self-monitoring, environmental change, dialogue with suppliers and networking among worksite canteens are applied....

  1. Regeneration after fire in campo rupestre : Short- and long-term vegetation dynamics

    OpenAIRE

    Le Stradic , Soizig; Hernandez , Pauline; Fernandes , Geraldo Wilson; Buisson , Elise

    2018-01-01

    International audience; The Cerrado (Brazilian savanna) is the second largest biome in Brazil, covering 22% of the country, and campo rupestre is one of the most biodiverse ecosystem. Campo rupestre are extremely old mountaintop tropical ecosystems, composed of a mosaic of herbaceous, shrubland and savanna vegetation, generally located above 900 m above sea level characterized by shallow, acidic and nutrient-poor soils. In the context of increased land-use changes, effective conservation and ...

  2. Short-term vegetation change on rehabilitated peatland on Rietvlei Nature Reserve

    Directory of Open Access Journals (Sweden)

    C.E. Venter

    2003-12-01

    Full Text Available Natural peatlands occur on the Rietvlei Nature Reserve. Before the Pretoria City Council acquired the land, these peatlands were mined by private land-owners. Ditches were constructed to drain the area for mining and the peatlands became desicrated. Later the area was proclaimed as a nature reserve and has since then been managed as such. Rehabilitation of the drained peatland on Rietvlei Nature Reserve first started in 2000 as a Working for Water project. The aim of the rehabilitation was to close the ditches and rewet the peatland, to enable possible revival of the peatland. A baseline vegetation survey was undertaken during the summer (March to April of 2001 to determine the nature of the pioneer communities that established on the rehabilitated area. This survey was repeated during the summer (March to April of 2002 to detect changes in the vegetation. The same sample plots were used on both occasions. The initial pioneer vegetation was mostly composed of weedy annuals.

  3. Long term trends in prevalence of neural tube defects in Europe

    DEFF Research Database (Denmark)

    Khoshnood, Babak; Loane, Maria; Walle, Hermien de

    2015-01-01

    STUDY QUESTION: What are the long term trends in the total (live births, fetal deaths, and terminations of pregnancy for fetal anomaly) and live birth prevalence of neural tube defects (NTD) in Europe, where many countries have issued recommendations for folic acid supplementation but a policy...... for mandatory folic acid fortification of food does not exist? METHODS: This was a population based, observational study using data on 11 353 cases of NTD not associated with chromosomal anomalies, including 4162 cases of anencephaly and 5776 cases of spina bifida from 28 EUROCAT (European Surveillance......-conceptional folic acid supplementation and existence of voluntary folic acid fortification. FUNDING, COMPETING INTERESTS, DATA SHARING: The study was funded by the European Public Health Commission, EUROCAT Joint Action 2011-2013. HD and ML received support from the European Commission DG Sanco during the conduct...

  4. Long-term trends in midwestern milkweed abundances and their relevance to monarch butterfly declines

    Science.gov (United States)

    Zaya, David N.; Pearse, Ian; Spyreas, Gregory

    2017-01-01

    Declines in monarch butterfly populations have prompted investigation into the sensitivity of their milkweed host plants to land-use change. Documented declines in milkweed abundance in croplands have spurred efforts to promote milkweeds in other habitats. Nevertheless, our current understanding of milkweed populations is poor. We used a long-term plant survey from Illinois to evaluate whether trends in milkweed abundance have caused monarch decline and to highlight the habitat-management practices that promote milkweeds. Milkweed abundance in natural areas has not declined precipitously, although when croplands are considered, changes in agricultural weed management have led to a 68% loss of milkweed available for monarchs across the region. Midsuccessional plant communities with few invasive species provide optimal milkweed habitat. The augmentation of natural areas and the management of existing grasslands, such as less frequent mowing and woody- and exotic-species control, may replace some of the milkweed that has been lost from croplands.

  5. Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation.

    Science.gov (United States)

    Lawrence, Dan; Philip, Graham; Hunt, Hannah; Snape-Kennedy, Lisa; Wilkinson, T J

    2016-01-01

    Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term.

  6. Long-term aerosol climatology over Indo-Gangetic Plain: Trend, prediction and potential source fields

    Science.gov (United States)

    Kumar, M.; Parmar, K. S.; Kumar, D. B.; Mhawish, A.; Broday, D. M.; Mall, R. K.; Banerjee, T.

    2018-05-01

    Long-term aerosol climatology is derived using Terra MODIS (Collection 6) enhanced Deep Blue (DB) AOD retrieval algorithm to investigate decadal trend (2006-2015) in columnar aerosol loading, future scenarios and potential source fields over the Indo-Gangetic Plain (IGP), South Asia. Satellite based aerosol climatology was analyzed in two contexts: for the entire IGP considering area weighted mean AOD and for nine individual stations located at upper (Karachi, Multan, Lahore), central (Delhi, Kanpur, Varanasi, Patna) and lower IGP (Kolkata, Dhaka). A comparatively high aerosol loading (AOD: 0.50 ± 0.25) was evident over IGP with a statistically insignificant increasing trend of 0.002 year-1. Analysis highlights the existing spatial and temporal gradients in aerosol loading with stations over central IGP like Varanasi (decadal mean AOD±SD; 0.67 ± 0.28) and Patna (0.65 ± 0.30) exhibit the highest AOD, followed by stations over lower IGP (Kolkata: 0.58 ± 0.21; Dhaka: 0.60 ± 0.24), with a statistically significant increasing trend (0.0174-0.0206 year-1). In contrast, stations over upper IGP reveal a comparatively low aerosol loading, having an insignificant increasing trend. Variation in AOD across IGP is found to be mainly influenced by seasonality and topography. A distinct "aerosol pool" region over eastern part of Ganges plain is identified, where meteorology, topography, and aerosol sources favor the persistence of airborne particulates. A strong seasonality in aerosol loading and types is also witnessed, with high AOD and dominance of fine particulates over central to lower IGP, especially during post-monsoon and winter. The time series analyses by autoregressive integrated moving average (ARIMA) indicate contrasting patterns in randomness of AOD over individual stations with better performance especially over central IGP. Concentration weighted trajectory analyses identify the crucial contributions of western dry regions and partial contributions from

  7. Elusive drought: uncertainty in observed trends and short- and long-term CMIP5 projections

    Directory of Open Access Journals (Sweden)

    B. Orlowsky

    2013-05-01

    Full Text Available Recent years have seen a number of severe droughts in different regions around the world, causing agricultural and economic losses, famines and migration. Despite their devastating consequences, the Standardised Precipitation Index (SPI of these events lies within the general range of observation-based SPI time series and simulations from the 5th phase of the Coupled Model Intercomparison Project (CMIP5. In terms of magnitude, regional trends of SPI over the last decades remain mostly inconclusive in observation-based datasets and CMIP5 simulations, but Soil Moisture Anomalies (SMAs in CMIP5 simulations hint at increased drought in a few regions (e.g., the Mediterranean, Central America/Mexico, the Amazon, North-East Brazil and South Africa. Also for the future, projections of changes in the magnitude of meteorological (SPI and soil moisture (SMA drought in CMIP5 display large spreads over all time frames, generally impeding trend detection. However, projections of changes in the frequencies of future drought events display more robust signal-to-noise ratios, with detectable trends towards more frequent drought before the end of the 21st century in the Mediterranean, South Africa and Central America/Mexico. Other present-day hot spots are projected to become less drought-prone, or display non-significant changes in drought occurrence. A separation of different sources of uncertainty in projections of meteorological and soil moisture drought reveals that for the near term, internal climate variability is the dominant source, while the formulation of Global Climate Models (GCMs generally becomes the dominant source of spread by the end of the 21st century, especially for soil moisture drought. In comparison, the uncertainty from Green-House Gas (GHG concentrations scenarios is negligible for most regions. These findings stand in contrast to respective analyses for a heat wave index, for which GHG concentrations scenarios constitute the main source

  8. Spatio-temporal long-term (1950-2009) temperature trend analysis in North Carolina, United States

    Science.gov (United States)

    Sayemuzzaman, Mohammad; Jha, Manoj K.; Mekonnen, Ademe

    2015-04-01

    This study analyzed long-term (1950-2009) annual and seasonal time series data of maximum and minimum temperature from 249 uniformly distributed stations across the State of North Carolina, United States. The Mann-Kendall and Theil-Sen approach were applied to quantify the significance and magnitude of trend, respectively. A pre-whitening technique was applied to eliminate the effect of lag-1 serial correlation. For most stations over the period of the past 60 years, the difference between minimum and maximum temperatures was found decreasing with an overall increasing trend in the mean temperature. However, significant trends (confidence level ≥ 95 %) in the mean temperature analysis were detected only in 20, 3, 23, and 20 % of the stations in summer, winter, autumn, and spring, respectively. The magnitude of the highest warming trend in minimum temperature and the highest cooling trend in maximum temperature was +0.073 °C/year in the autumn season and -0.12 °C/year in the summer season, respectively. Additional analysis in mean temperature trend was conducted on three regions of North Carolina (mountain, piedmont, and coastal). The results revealed a warming trend for the coastal zone, a cooling trend for the mountain zone, and no distinct trend for the piedmont zone. The Sequential Mann-Kendall test results indicated that the significant increasing trends in minimum temperature and decreasing trend in maximum temperature had begun around 1970 and 1960 (change point), respectively, in most of the stations. Finally, the comparison between mean surface air temperature (SAT) and the North Atlantic Oscillation (NAO) concluded that the variability and trend in SAT can be explained partially by the NAO index for North Carolina.

  9. Underweight and overweight among children and adolescents in Tuscany (Italy). Prevalence and short-term trends.

    Science.gov (United States)

    Lazzeri, G; Rossi, S; Pammolli, A; Pilato, V; Pozzi, T; Giacchi, M V

    2008-03-01

    The recent increase in both childhood obesity and adolescent anorexia nervosa in developed countries has underlined the important consequences that these trends may have on public health, as there is an increased risk that these conditions may become chronic diseases in adulthood. Therefore, it is necessary to monitor prevalence rates and trends in thinness and overweight (including obesity) among children and adolescents at different levels: international, national and sub-national. Since 2001/2002, a nutritional surveillance system has been implemented in the Tuscany Region to estimate the nutritional status and lifestyles of children and adolescents. The main objectives were to assess the prevalence of thinness, overweight and obesity among Tuscan children and adolescents and to provide baseline information on the prevalence of thinness, for the first time calculated according to the new international definitions, for geographical comparisons and descriptions of time trends. Independent cross-sectional sample surveys were conducted in 2002, 2004 and 2006 in Tuscany, North-Central Italy. Data were collected from stratified two-stage cluster samples of children aged 9 years (n = 3,048 in 2002 and n = 1,430 in 2006) and of adolescents aged 11-13-15 years (n = 1,066, n = 1185 and n = 1,160 in 2004 and n = 1,189, n = 1,211 and n = 1,178 in 2006, respectively). Weights and heights of primary school children were measured by means of standardized methods, while those of adolescents were self-reported. Decimal age was calculated from the date of birth to the date of measurement. Body Mass Index classes were calculated according to the International Obesity Task Force standards. Instead of the term underweight in children, we used the term thinness, which the World Health Organization uses to mean low Body Mass Index for age in adults and adolescents. According to Cole's recently published cut-offs for thinness, we divided our Body Mass Index values below 18.5 into three

  10. Effects of various uranium leaching procedures on soil: Short-term vegetation growth and physiology. Progress report, April 1994

    International Nuclear Information System (INIS)

    Edwards, N.T.

    1994-08-01

    Significant volumes of soil containing elevated levels of uranium exist in the eastern United States. The contamination resulted from the development of the nuclear industry in the United States requiring a large variety of uranium products. The contaminated soil poses a collection and disposal problem of a magnitude that justifies the development of decontamination methods. Consequently, the Department of Energy (DOE) Office of Technology Development formed the Uranium Soils Integrated Demonstration (USID) program to address the problem. The fundamental goal of the USID task group has been the selective extraction/leaching or removal of uranium from soil faster, cheaper, and safer than what can be done using current conventional technologies. The objective is to selectively remove uranium from soil without seriously degrading the soil's physicochemical characteristics and without generating waste that is difficult to manage and/or dispose of. However, procedures developed for removing uranium from contaminated soil have involved harsh chemical treatments that affect the physicochemical properties of the soil. The questions are (1) are the changes in soil properties severe enough to destroy the soil's capacity to support and sustain vegetation growth and survival? and (2) what amendments might be made to the leached soil to return it to a reasonable vegetation production capacity? This study examines the vegetation-support capacity of soil that had been chemically leached to remove uranium. The approach is to conduct short-term germination and phytotoxicity tests for evaluating soils after they are subjected to various leaching procedures followed by longer term pot studies on successfully leached soils that show the greatest capacity to support plant growth. This report details the results from germination and short-term phytotoxicity testing of soils that underwent a variety of leaching procedures at the bench scale at ORNL and at the pilot plant at Fernald

  11. Aid alignment: a longer term lens on trends in development assistance for health in Uganda.

    Science.gov (United States)

    Stierman, Elizabeth; Ssengooba, Freddie; Bennett, Sara

    2013-02-20

    Over the past decade, development assistance for health (DAH) in Uganda has increased dramatically, surpassing the government's own expenditures on health. Yet primary health care and other priorities identified in Uganda's health sector strategic plan remain underfunded. Using data available from the Creditor Reporting System (CRS), National Health Accounts (NHA), and government financial reports, we examined trends in how donors channel DAH and the extent to which DAH is aligned with sector priorities. The study follows the flow of DAH from the donor to the implementing organization, specifying the modality used for disbursing funds and categorizing funds based on program area or support function. Despite efforts to improve alignment through the formation of a sector-wide approach (SWAp) for health in 1999 and the creation of a fund to pool resources for identified priorities, increasingly DAH is provided as short-term, project-based support for disease-specific initiatives, in particular HIV/AIDS. These findings highlight the need to better align external resources with country priorities and refocus attention on longer-term sector-wide objectives.

  12. Temporal trends in respiratory mortality and short-term effects of air pollutants in Shenyang, China.

    Science.gov (United States)

    Xue, Xiaoxia; Chen, Jianping; Sun, Baijun; Zhou, Baosen; Li, Xuelian

    2018-04-01

    Short-term exposures to air pollution are associated with acute effects on respiratory health. This study aimed to describe 10-year temporal trends in respiratory mortality in the urban areas of Shenyang, China, according to gender and age and estimate the effects of air pollution on respiratory diseases (ICD-10J00-J99) and lung cancer (ICD-10 C33-C34) using a case-crossover design. During the study period 2013-2015, the exposure-response relationship between ambient air pollutants and mortality data was fitted by a quasi-Poisson model. Age-standardized mortality rates for a combined number of respiratory diseases and for lung cancer declined in Shenyang; however, death counts increased with aging. Deaths from respiratory diseases increased by 4.7% (95% CI, 0.00-9.9), and lung cancer mortality increased by 6.5% (95% CI, 1.2-12.0), both associated with a 10 μg/m 3 increase in exposure to particulate matter pollutants. These results provided an updated estimate of the short-term effects of air pollution in Shenyang. Since population aging is also associated with increasing mortality from respiratory diseases and lung cancer, reinforcing air quality control measures and health-promoting behaviors is urgent and necessary in Shenyang.

  13. The long-term trend of carbon-14 level in Japan

    International Nuclear Information System (INIS)

    Yoshikazu Inoue; Tetsuo Iwakura

    1993-01-01

    The long-term trend of the specific activity of 14 C in terms of dpm/gC from 1942 to 1991 in the natural environment in Japan was obtained as baseline data by analyzing plant components so as to evaluate the collective effective dose. It was deduced that the specific activity of 14 C in plants reflected well that of atmospheric 14 CO 2 . Uniform distribution of the specific activity in plant among species as well as the production places was confirmed. The Suess effect was observed clearly for a period of 10 years from the late 1960's. The 14 C level was at about 13.7 dpm/gC due to cosmic ray production in 1940's, and reached a peak of about 24.5 dpm/gC in 1963 due to nuclear weapons testing and decreased to 15.6 dpm/gC in 1991. Fermented alcohol proved to be a convenient indicator for measuring the annual mean specific activity of 14 C in the atmosphere. (3 figs.)

  14. Hawaiian forest bird trends: using log-linear models to assess long-term trends is supported by model diagnostics and assumptions (reply to Freed and Cann 2013)

    Science.gov (United States)

    Camp, Richard J.; Pratt, Thane K.; Gorresen, P. Marcos; Woodworth, Bethany L.; Jeffrey, John J.

    2014-01-01

    Freed and Cann (2013) criticized our use of linear models to assess trends in the status of Hawaiian forest birds through time (Camp et al. 2009a, 2009b, 2010) by questioning our sampling scheme, whether we met model assumptions, and whether we ignored short-term changes in the population time series. In the present paper, we address these concerns and reiterate that our results do not support the position of Freed and Cann (2013) that the forest birds in the Hakalau Forest National Wildlife Refuge (NWR) are declining, or that the federally listed endangered birds are showing signs of imminent collapse. On the contrary, our data indicate that the 21-year long-term trends for native birds in Hakalau Forest NWR are stable to increasing, especially in areas that have received active management.

  15. Long-term atmospheric visibility trend in Southeast China, 1973-2010

    Science.gov (United States)

    Deng, Junjun; Du, Ke; Wang, Kai; Yuan, Chung-Shin; Zhao, Juanjuan

    2012-11-01

    Particulate matter (PM) pollution in Southeast China has been worsening because of the rapid industrial development and urbanization, which have significant negative effects on atmospheric visibility. Characterization of the trend in atmospheric visibility is important for evaluating the impact of PM pollution on the impairment of visual air quality in urban and rural areas. Long-term trend in atmospheric visibility in Southeast China was analyzed for the period of 1973-2010 based on the meteorological data from the National Climatic Data Center (NCDC) database using four statistical methods: annual mean visibility, percentages of “very good” visibility and “bad” visibility, ridit analysis, and cumulative percentiles. The relationship of atmospheric extinction with Air Pollution Index (API) was studied. In addition, the effects of recent environment policies on visibility were studied. The results showed that the visibility had decreased in 94% stations of this region and prefecture stations had the highest decreasing trend of -3.1 km/decade during the entire period. The average visibility of all the 17 stations (i.e., region-average) declined at a rate of -2.0 km/decade, with a 38-year average of 18.1 km. Decrease in the percentage of “very good” visibility and increase in the percentage of “bad” visibility existed in 14 and 16 stations, respectively. Region-average percentage of “bad” visibility was in the range of 2.2-21.5%, with an increasing rate of 5.0% per decade, and that of “very good” visibility was 24.4-71.8%, with a decreasing rate of -10.7% per decade. During the entire period, county and prefecture stations had similar changing patterns and trends in visibility, while town stations had the least worsening trends. Region-average visibility was better before 1988 while worse after 1993 when comparing to the entire period, with the transition period of 1988-1993. The worst 20%, 50% and best 20% of region-average visibility

  16. A mathematical model for lake ontogeny in terms of filling with sediments and macrophyte vegetation

    International Nuclear Information System (INIS)

    Brydsten, Lars

    2004-05-01

    A mathematical model for simulation of lake basin filling processes in areas with positive shore displacement was constructed. The model was calibrated using sediment and catchments data from eight existing lake basins situated in the northern coastal area of the province of Uppland, Sweden. The lake basin filling processes were separated into three phases: basin filling with wave-washed material (silt, silty sand or sand), filling with fine-grained material during the shallow gulf and lake stages, respectively, and filling with vegetation during the lake stage. The basin filling rates for wave-washed material were generally low but varied considerably both between and within lakes. The mean basin filling rate of wave-washed material was 4.1%. The volume of inorganic sediments produced, and basin filling rates during the shallow gulf and lake phases were determined for all the eight lakes. The relationship between basin filling rate and parameters describing the catchments, the former postglacial basins and the lakes, respectively, was determined using multiple regression analysis. The basin filling rate with inorganic sediments was best described by parameters related to former postglacial basin morphometry and current lake morphometry, e.g. basin volume, lake volume, and lake area. The goodness of fit turned out to be 0.99 for a simple regression with basin volume as the sole independent variable. The basin filling with vegetation (Phragmites australis followed by Sphagnum spp.) was treated as a 2-dimensional process. A dataset with 84 bogs was selected from a digital soil map. The ages of the bogs were calculated using a digital elevation map and an equation for shore displacement. The choke-up rate was then calculated by dividing the area of the bogs with their age. A strong exponential relationship exists between areas of the bogs and choke-up rat, and this relationship was then used in the model. The resulting model starts by filling the former coastal basin

  17. A mathematical model for lake ontogeny in terms of filling with sediments and macrophyte vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Brydsten, Lars [Umeaa Univ. (Sweden). Dept. of Biology and Environmental Science

    2004-05-01

    A mathematical model for simulation of lake basin filling processes in areas with positive shore displacement was constructed. The model was calibrated using sediment and catchments data from eight existing lake basins situated in the northern coastal area of the province of Uppland, Sweden. The lake basin filling processes were separated into three phases: basin filling with wave-washed material (silt, silty sand or sand), filling with fine-grained material during the shallow gulf and lake stages, respectively, and filling with vegetation during the lake stage. The basin filling rates for wave-washed material were generally low but varied considerably both between and within lakes. The mean basin filling rate of wave-washed material was 4.1%. The volume of inorganic sediments produced, and basin filling rates during the shallow gulf and lake phases were determined for all the eight lakes. The relationship between basin filling rate and parameters describing the catchments, the former postglacial basins and the lakes, respectively, was determined using multiple regression analysis. The basin filling rate with inorganic sediments was best described by parameters related to former postglacial basin morphometry and current lake morphometry, e.g. basin volume, lake volume, and lake area. The goodness of fit turned out to be 0.99 for a simple regression with basin volume as the sole independent variable. The basin filling with vegetation (Phragmites australis followed by Sphagnum spp.) was treated as a 2-dimensional process. A dataset with 84 bogs was selected from a digital soil map. The ages of the bogs were calculated using a digital elevation map and an equation for shore displacement. The choke-up rate was then calculated by dividing the area of the bogs with their age. A strong exponential relationship exists between areas of the bogs and choke-up rat, and this relationship was then used in the model. The resulting model starts by filling the former coastal basin

  18. Trends in precipitation extremes and long-term memory of runoff records in Zhejiang, East China

    NARCIS (Netherlands)

    Tian, Y.; Tian, Ye; Xu, YuePing; Booij, Martijn J.; Zhang, Qingqing; Lin, Shengji; Franks, Steward W.; Boegh, Eva; Blyth, Eleanor; Hannah, David M.; Yilmaz, Koray K.

    2011-01-01

    Extreme weather events have a huge impact on human beings and therefore it is of vital importance to investigate trends in relevant climatological and hydrological variables. In this study, precipitation and streamflow trends in Zhejiang Province in east China are analysed. Trends in annual and

  19. Long-term trends of surface ozone and its influencing factors at the Mt. Waliguan GAW station, China - Part 1: Overall trends and characteristics

    Science.gov (United States)

    Xu, W. Y.; Lin, W. L.; Xu, X. B.; Tang, J.; Huang, J. Q.; Wu, H.; Zhang, X. C.

    2015-11-01

    Tropospheric ozone is an important atmospheric oxidant, greenhouse gas and atmospheric pollutant at the same time. The level of tropospheric ozone, particularly in the surface layer, is impacted by emissions of precursors and is subjected to meteorological conditions. Due its importance, the long-term variation trend of baseline ozone is highly needed for environmental and climate change assessment. So far, studies about the long-term trends of ozone at representative sites are mainly available for European and North American sites. Similar studies are lacking for China, a country with rapid economic growth for recent decades, and many other developing countries. To uncover the long-term characteristics and trends of baseline surface ozone, concentration in western China, measurements at a global baseline Global Atmospheric Watch (GAW) station in the north-eastern Tibetan Plateau region (Mt. Waliguan) for the period of 1994 to 2013 were analysed in this study, using a modified Mann-Kendall test and the Hilbert-Huang Transform analysis for the trend and periodicity analysis, respectively. Results reveal higher surface ozone during the night and lower during the day at Waliguan, due to mountain-valley breezes. A seasonal maximum in summer was found, which was probably caused by enhanced stratosphere-to-troposphere exchange events and/or by tropospheric photochemistry. Analysis suggests that there is a season-diurnal cycle in the three-dimensional winds on top of Mt. Waliguan. Season-dependent daytime and nighttime ranges of 6 h were determined based on the season-diurnal cycle in the three-dimensional winds and were used to sort subsets of ozone data for trend analysis. Significant increasing trends in surface ozone were detected for both daytime (1.5-2.7 ppbv 10 a-1) and nighttime (1.3-2.9 ppbv 10 a-1). Autumn and spring revealed the largest increase rates, while summer and winter showed relatively weaker increases. The HHT spectral analysis confirmed the increasing

  20. Long Term Evaluation of Yield Stability Trend for Cereal Crops in Iran

    Directory of Open Access Journals (Sweden)

    mehdi nassiri mahalati

    2016-05-01

    Full Text Available During the last few decades cereals yield have increased drastically at the national level however, information about yield stability and its resistance to annual environmental variability are scare. In this study long term stability of grin yield of wheat, barley, rice, corn and overall cereals in Iran were evaluated during a 40-year period (1971-2011. Stability analysis was conducted using two different methods. In the first method the residuals of regression between crop yield and time (years were calculated as stability index. For this different segmented regression models including linear, bi-linear and tri-linear were fitted to yield trend data and the best model for each crop was selected based on statistical measures. Absolute residuals (the difference between actual and predicted yields for each year as well as relative residuals (absolute residuals as percent of predicted yield were estimated. In the second method yield stability was estimated from the slope of the regression line between average annual yield of all cereals (environmental index and the yield of each crop in the same year. Results indicted that in wheat and barley absolute and relative residuals were increased during the study period leading to reduction of stability despite considerable yield increment. However, for rice and corn residuals followed a decreasing trend and therefore yield stability of these crops was increased during the last 40 years. The same result was obtained with the environmental index but in this method reduction of yield stability in barley was lower than wheat. Based on the results, yield and yield stability of cereals crops in Iran increased during the last 40 years. However, the percentage increase in stability is lower than that of yield. Application of nitrogen fertilizers was led to reduction in stability. Yield stability of wheat, barley, rice, corn and overall cereals was improved with increasing their cultivated area.

  1. Long-Term Trend and Seasonal Variability of Horizontal Visibility in Nigerian Troposphere

    Directory of Open Access Journals (Sweden)

    Mukhtar Balarabe

    2015-10-01

    Full Text Available A study of the long-term variability; trend and characteristics of visibility in four zones of Nigeria was carried out. Visibility and other meteorological data from NOAA-NCDC and aerosol index data over Nigeria during 1984–2013 are analyzed using time series and  simple regression model. There are significant decreasing trends for every region and season during the 30-years period; the fluctuations exhibited nearly similar pattern. The 30-year mean visibilities for the four zones (Sahel; North Central; Southern; and Coastal were 13.8 ± 3.9; 14.3 ± 4.2; 13.6 ± 3.5 and 12.8 ± 3.1 km with decreasing trends at the rates of 0.08; 0.06; 0.02 and 0.02 km/year. In all the zones; visibilities were better in summer while worse in Harmattan (dry season. During summer visibility was best in Sahel and North-central; however; in Harmattan visibility was best in southern and coastal zones. It was best between May and June (17.6; 18.9; 16.6 and 15.1 km with a second peak in September. The 30-year seasonal averages were 16.2 ± 2.1; 16.8 ± 2.4; 15.4 ± 1.8 and 14.0 ± 2.2 km in summer; and 10.2 ± 2.5; 10.9 ± 2.9; 11.0 ± 3.3 and 11.4 ± 3.0 km in Harmattan for the respective zones. Sahel and North Central had the worse visibility reduction during Harmattan compared with Southern and coastal areas. An analysis based on simple regression equation reveals a strong and negative relationship between visibility on one hand; AI; and AOD on the other hand. The analysis also discusses the variability regarding the frequency of occurrence of a dust storm; dust haze; and good visibility over the period of study.

  2. Employment trends during preschool years among mothers of term singletons born with low birth weight.

    Science.gov (United States)

    Hauge, Lars Johan; Kornstad, Tom; Nes, Ragnhild Bang; Kristensen, Petter; Irgens, Lorentz M; Landolt, Markus A; Eskedal, Leif T; Vollrath, Margarete E

    2014-11-01

    Children born at term with low birth weight (LBW) are regarded growth restricted and are at particular risk of adverse health outcomes requiring a high degree of parental participation in the day-to-day care. This study examined whether their increased risk of special health care needs compared to other children may influence mothers' opportunities for participation in the labor market at different times after delivery. Data from 32,938 participants in the population-based Norwegian Mother and Child Cohort Study with singleton children born at term in 2004-2006 were linked to national registers in order to investigate the mothers' employment status when their children were 1-3 years in 2007 and 4-6 years in 2010. Children weighing less than two standard deviations below the gender-specific mean were defined as LBW children. Although not significantly different from mothers of children in the normal weight range, mothers of LBW children had the overall highest level of non-employment when the children were 1-3 years. At child age 4-6 years on the other hand, LBW was associated with an increased risk of non-employment (RR 1.39: 95 % CI 1.11-1.75) also after adjustment for factors associated with employment in general. In accordance with employment trends in the general population, our findings show that while mothers of normal birth weight children re-enter the labor market as their children grow older, mothers of LBW children born at term participate to a lesser extent in paid employment and remain at levels similar to those of mothers with younger children.

  3. Long-term trends of sulfur deposition in East Asia during 1981-2005

    Science.gov (United States)

    Kuribayashi, Masatoshi; Ohara, Toshimasa; Morino, Yu; Uno, Itsushi; Kurokawa, Jun-ichi; Hara, Hiroshi

    2012-11-01

    We used a chemical transport model to investigate the long-term trends of sulfur deposition in East Asia during 1981-2005. The model reproduced the observed spatial distributions in East Asia of the rate of wet deposition of non-seasalt sulfate (nss-SO42-), volume-weighted mean concentrations of nss-SO42- in precipitation, precipitation, and concentrations in air of gaseous sulfur dioxide and particulate nss-SO42-. The model also reproduced well observed seasonal variations and long-term trends of wet deposition of nss-SO42- in Japan from 1988 to 2005. The increasing rate of wet deposition of nss-SO42- in Japan during 1991-2005 was demonstrated with 99.9% significance for both observed and modeled data. The annual rate of total (wet + dry) sulfur deposition in Japan increased from 15.6 Gmol S y-1 in 1981-1985 to 23.9 Gmol S y-1 in 2001-2005 in response to both increasing contributions from Chinese emissions and the eruption of Miyakejima volcano in 2000. During that 25-year period, approximately 2.1% of the sulfur from Chinese emissions was deposited in Japan. Over the same period, the rate of deposition of sulfur in East Asia increased gradually from 14.2 mmol S m-2 y-1 to 24.0 mmol S m-2 y-1, and the contribution of emissions from China to total sulfur deposition in East Asia increased from 65% to 77%. The contribution of Miyakejima volcano was 3% during 2001-2005. The increase in the sulfur deposition rate was remarkably high on the North China Plain, around Guangzhou, and south of Chongqing. The rate of increase in East Asia was greatest in winter, although the rate of sulfur deposition was highest in summer. Sulfur flux from China to Japan increased by a factor of 2.5 at altitudes of 0-3000 m from 1981 to 2005.

  4. Interactions of Flow, Sediment Transport, and Vegetation in the Long-Term Evolution of Arroyos

    Science.gov (United States)

    Perignon, M. C.; Griffin, E. R.; Tucker, G. E.; Friedman, J. M.; Overeem, I.

    2014-12-01

    Arroyos in the Southwestern United States have experienced multiple cut-and-fill cycles in the late Quaternary. Extensive studies fo the Lower Rio Puerco, New Mexico, USA, show that it has most recently progressed from an (1) unincised state with a broad floodplain in the mid 1800s, through a period of (2) incision, forming a deep gully with steep walls by the early 1900s, and to the (3) present-day stage of arroyo widening and filling. The arroyo cycle is driven by a combination of autogenic processes and external forcings, although the relative influence of each process is under debate. We use the morphodynamic model ANUGA to explore the influences of discharge, sediment transport, and vegetation on the geomorphic evolution of the Lower Rio Puerco through the arroyo cycle. The predictive power of the numerical model is first established by using it to hind-cast the morphologic evolution of a reach of the river during a large flood in 2006, and comparing the model predictions to real-world magnitudes and patterns of topographic change recorded for this event by multi-temporal airborne lidar. The morphodynamic model is then used to simulate the response of this stream to floods in the past. A comprehensive dataset of the topography and hydrology of the Lower Rio Puerco since the 1920s is used to reproduce the morphology of the arroyo at multiple points in time, and historical descriptions serve to extrapolate these into the 19th century. We test the sensitivity of the reconstructed landscapes to changes in peak discharge, sediment supply, and the distribution and characteristics of vegetation in order to determine the relative influence of each forcing in the evolution of the stream, and to understand how the interactions of different processes could drive its progression through the arroyo cycle.

  5. Detecting Long-term Trend of Water Quality Indices of Dong-gang River, Taiwan Using Quantile Regression

    Science.gov (United States)

    Yang, D.; Shiau, J.

    2013-12-01

    ABSTRACT BODY: Abstract Surface water quality is an essential issue in water-supply for human uses and sustaining healthy ecosystem of rivers. However, water quality of rivers is easily influenced by anthropogenic activities such as urban development and wastewater disposal. Long-term monitoring of water quality can assess whether water quality of rivers deteriorates or not. Taiwan is a population-dense area and heavily depends on surface water for domestic, industrial, and agricultural uses. Dong-gang River is one of major resources in southern Taiwan for agricultural requirements. The water-quality data of four monitoring stations of the Dong-gang River for the period of 2000-2012 are selected for trend analysis. The parameters used to characterize water quality of rivers include biochemical oxygen demand (BOD), dissolved oxygen (DO), suspended solids (SS), and ammonia nitrogen (NH3-N). These four water-quality parameters are integrated into an index called river pollution index (RPI) to indicate the pollution level of rivers. Although widely used non-parametric Mann-Kendall test and linear regression exhibit computational efficiency to identify trends of water-quality indices, limitations of such approaches include sensitive to outliers and estimations of conditional mean only. Quantile regression, capable of identifying changes over time of any percentile values, is employed in this study to detect long-term trend of water-quality indices for the Dong-gang River located in southern Taiwan. The results show that Dong-gang River 4 stations from 2000 to 2012 monthly long-term trends in water quality.To analyze s Dong-gang River long-term water quality trends and pollution characteristics. The results showed that the bridge measuring ammonia Long-dong, BOD5 measure in that station on a downward trend, DO, and SS is on the rise, River Pollution Index (RPI) on a downward trend. The results form Chau-Jhou station also ahowed simialar trends .more and more near the

  6. Improving simulated long-term responses of vegetation to temperature and precipitation extremes using the ACME land model

    Science.gov (United States)

    Ricciuto, D. M.; Warren, J.; Guha, A.

    2017-12-01

    While carbon and energy fluxes in current Earth system models generally have reasonable instantaneous responses to extreme temperature and precipitation events, they often do not adequately represent the long-term impacts of these events. For example, simulated net primary productivity (NPP) may decrease during an extreme heat wave or drought, but may recover rapidly to pre-event levels following the conclusion of the extreme event. However, field measurements indicate that long-lasting damage to leaves and other plant components often occur, potentially affecting the carbon and energy balance for months after the extreme event. The duration and frequency of such extreme conditions is likely to shift in the future, and therefore it is critical for Earth system models to better represent these processes for more accurate predictions of future vegetation productivity and land-atmosphere feedbacks. Here we modify the structure of the Accelerated Climate Model for Energy (ACME) land surface model to represent long-term impacts and test the improved model against observations from experiments that applied extreme conditions in growth chambers. Additionally, we test the model against eddy covariance measurements that followed extreme conditions at selected locations in North America, and against satellite-measured vegetation indices following regional extreme events.

  7. Vegetative filter strips efficiency controlling soil loss and trapping herbicides in two olive orchards at the short-term

    Science.gov (United States)

    de Luna, Elena; Guzmán, Gema; Gómez, José A.

    2014-05-01

    The optimization of water use in a semi-arid climate is based on an optimal use of rainwater adopting management practices that prevent and/or control runoff. This is a key point for increasing the economic and environmental sustainability of agriculture due to the minimization of diffuse pollution associated to runoff and to sediment and chemical transport. One strategy is the establishment of vegetative filters strips that prevent pesticides (Stehle et al. 2011), herbicides (Vianello et al. 2005), fertilizers (Withers et al. 2009) and runoff-sediment (Campo-Bescós et al. 2013) from entering streams or surface water reservoirs. To evaluate the short-term risks associated with the use of herbicides a trial was designed in two olive groves located in Benacazón (Sevilla) and Cabra (Córdoba) both with an average steepness of 11%. Two different management systems were evaluated, bare soil and bare soil with vegetative filter strips. Pre-emergence herbicides were applied and analysed at the beginning of the trial by chromatography GC-MS and after each rainfall event both in soil and sediment. Runoff and soil losses were measured, as well. The results obtained from this study show that soil management practices such as, the use of vegetative filter strips results in a reduction of soil losses and runoff. This it is translated in the improvement of soil quality and a reduction of water pollution caused by the use of herbicides. This information will improve the understanding of insufficiently known aspects and it will help to increase the knowledge for a better implementation of sustainable management practices at a farm scale and at larger temporal scale. References: Campo-Bescós, M. A., Muñoz-Carpena, R., & Kiker, G. (2013) Influencia del suelo en la eficiencia de la implantación de filtros verdes en un distrito de riego por superficie en medio árido. En Estudios de la Zona no Saturada del Suelo, Vol. XI: 183-187. Stehle, S., Elsaesser, D., Gregoire, C., Imfeld

  8. A Systematic Review of Global Publication Trends Regarding Long-Term Outcomes of ADHD

    Science.gov (United States)

    Hodgkins, Paul; Arnold, L. Eugene; Shaw, Monica; Caci, Hervé; Kahle, Jennifer; Woods, Alisa G; Young, Susan

    2012-01-01

    There is increased global recognition of attention deficit hyperactivity disorder (ADHD) as a serious medical condition with long-term consequences. Although originally conceived of as a childhood disorder, ADHD is being increasingly recognized in adults. Individual geographic regions may have specific interests and objectives for the study of ADHD. A systematic review of long-term outcomes (LTOs) in ADHD was conducted to evaluate research on ADHD LTOs on a global scale. Studies that were at least 2 years in duration were examined. A total of 351 studies were identified in the final analysis. We identified nine outcomes of interest and classified studies by specific geographical regions, age groups studied and study design by region and over time. Published studies of LTOs in ADHD have increased in all geographical regions over the past three decades, with a peak number of 42 publications in 2008. This rise in publications on ADHD LTOs may reflect a rise in global interest and recognition of consequences and impairment associated with ADHD. Although many world regions have published on ADHD LTOs, the majority of studies have emerged from the US and Canada, followed by Europe. While investigators in the US and Canada were predominantly interested in drug addiction as a LTO, European researchers were more interested in antisocial behavior, and Eastern Asian investigators focused on both of these LTOs as well as self-esteem. Geographical differences in the focus of ADHD LTO studies may reflect regional variations in cultural values. Proportionally fewer prospective longitudinal studies and proportionally more retrospective and cross-sectional studies have been published in more recent decades. Finally, more studies focusing on ADHD in adolescents and adults have been conducted in recent years, and particularly adolescents in Eastern Asia. These changes in basic study design may reflect an increase in the recognition that ADHD is a lifetime chronic disorder. This

  9. Assessing variability and long-term trends in burned area by merging multiple satellite fire products

    Directory of Open Access Journals (Sweden)

    L. Giglio

    2010-03-01

    Full Text Available Long term, high quality estimates of burned area are needed for improving both prognostic and diagnostic fire emissions models and for assessing feedbacks between fire and the climate system. We developed global, monthly burned area estimates aggregated to 0.5° spatial resolution for the time period July 1996 through mid-2009 using four satellite data sets. From 2001–2009, our primary data source was 500-m burned area maps produced using Moderate Resolution Imaging Spectroradiometer (MODIS surface reflectance imagery; more than 90% of the global area burned during this time period was mapped in this fashion. During times when the 500-m MODIS data were not available, we used a combination of local regression and regional regression trees developed over periods when burned area and Terra MODIS active fire data were available to indirectly estimate burned area. Cross-calibration with fire observations from the Tropical Rainfall Measuring Mission (TRMM Visible and Infrared Scanner (VIRS and the Along-Track Scanning Radiometer (ATSR allowed the data set to be extended prior to the MODIS era. With our data set we estimated that the global annual area burned for the years 1997–2008 varied between 330 and 431 Mha, with the maximum occurring in 1998. We compared our data set to the recent GFED2, L3JRC, GLOBCARBON, and MODIS MCD45A1 global burned area products and found substantial differences in many regions. Lastly, we assessed the interannual variability and long-term trends in global burned area over the past 13 years. This burned area time series serves as the basis for the third version of the Global Fire Emissions Database (GFED3 estimates of trace gas and aerosol emissions.

  10. A systematic review of long-term outcomes in ADHD: global publication trends

    Directory of Open Access Journals (Sweden)

    Paul eHodgkins

    2012-01-01

    Full Text Available There is increased global recognition of attention deficit hyperactivity disorder (ADHD as a serious medical condition with long-term consequences. Although originally conceived of as a childhood disorder, ADHD is being increasingly recognized in adults. Individual geographic regions may have specific interests and objectives for the study of ADHD. A systematic review of long-term outcomes (LTOs in ADHD was conducted to evaluate research on ADHD LTOs on a global scale. Studies that were at least two years in duration were examined. We identified nine outcomes of interest and classified studies by specific geographical regions, age groups studied and study design by region and over time. Published studies of LTOs in ADHD have increased in all geographical regions over the past three decades, with a peak number of publications in 2008. Although many world regions have published on ADHD LTOs, the majority of studies have emerged from the US and Canada, followed by Europe. While investigators in the US and Canada were predominantly interested in drug addiction as a LTO, European researchers were more interested in antisocial behavior, and Eastern Asian investigators focused on both of these LTOs as well as self-esteem. Proportionally fewer prospective longitudinal studies and proportionally more retrospective and cross-sectional studies have been published in more recent decades. Finally, more studies focusing on ADHD in adolescents and adults have been conducted in recent years, and particularly adolescents in Eastern Asia. This systematic review analysis of publication trends in ADHD LTOs reflects geographically-based interests that change over time.

  11. Long-term trends of native and non-native fish faunas in the American Southwest

    Directory of Open Access Journals (Sweden)

    Olden, J. D.

    2005-06-01

    Full Text Available Environmental degradation and the proliferation of non-native fish species threaten the endemic, and highly unique fish faunas of the American Southwest. The present study examines long-term trends (> 160 years of fish species distributions in the Lower Colorado River Basin and identifies those native species (n = 28 exhibiting the greatest rates of decline and those non-native species (n = 48 exhibiting the highest rates of spread. Among the fastest expanding invaders in the basin are red shiner (Cyprinella lutrensis, fathead minnow (Pimephales promelas, green sunfish (Lepomis cyanellus, largemouth bass (Micropterus salmoides, western mosquitofish (Gambussia affinis and channel catfish (Ictalurus punctatus; species considered to be the most invasive in terms of their negative impacts on native fish communities. Interestingly, non-native species that have been recently introduced (1950+ have generally spread at substantially lower rates as compared to species introduced prior to this time (especially from 1920 to 1950, likely reflecting reductions in human-aided spread of species. We found general agreement between patterns of species decline and extant distribution sizes and official listing status under the U.S. Endangered Species Act. ‘Endangered’ species have generally experienced greater declines and have smaller present-day distributions compared to ‘threatened’ species, which in turn have shown greater declines and smaller distributions than those species not currently listed. A number of notable exceptions did exist, however, and these may provide critical information to help guide the future listing of species (i.e., identification of candidates and the upgrading or downgrading of current listed species that are endemic to the Lower Colorado River Basin. The strong correlation between probability estimates of local extirpation and patterns of native species decline and present-day distributions suggest a possible proactive

  12. A systematic review of global publication trends regarding long-term outcomes of ADHD.

    Science.gov (United States)

    Hodgkins, Paul; Arnold, L Eugene; Shaw, Monica; Caci, Hervé; Kahle, Jennifer; Woods, Alisa G; Young, Susan

    2011-01-01

    There is increased global recognition of attention deficit hyperactivity disorder (ADHD) as a serious medical condition with long-term consequences. Although originally conceived of as a childhood disorder, ADHD is being increasingly recognized in adults. Individual geographic regions may have specific interests and objectives for the study of ADHD. A systematic review of long-term outcomes (LTOs) in ADHD was conducted to evaluate research on ADHD LTOs on a global scale. Studies that were at least 2 years in duration were examined. A total of 351 studies were identified in the final analysis. We identified nine outcomes of interest and classified studies by specific geographical regions, age groups studied and study design by region and over time. Published studies of LTOs in ADHD have increased in all geographical regions over the past three decades, with a peak number of 42 publications in 2008. This rise in publications on ADHD LTOs may reflect a rise in global interest and recognition of consequences and impairment associated with ADHD. Although many world regions have published on ADHD LTOs, the majority of studies have emerged from the US and Canada, followed by Europe. While investigators in the US and Canada were predominantly interested in drug addiction as a LTO, European researchers were more interested in antisocial behavior, and Eastern Asian investigators focused on both of these LTOs as well as self-esteem. Geographical differences in the focus of ADHD LTO studies may reflect regional variations in cultural values. Proportionally fewer prospective longitudinal studies and proportionally more retrospective and cross-sectional studies have been published in more recent decades. Finally, more studies focusing on ADHD in adolescents and adults have been conducted in recent years, and particularly adolescents in Eastern Asia. These changes in basic study design may reflect an increase in the recognition that ADHD is a lifetime chronic disorder. This

  13. Modelling impacts of atmospheric deposition and temperature on long-term DOC trends.

    Science.gov (United States)

    Sawicka, K; Rowe, E C; Evans, C D; Monteith, D T; E I Vanguelova; Wade, A J; J M Clark

    2017-02-01

    It is increasingly recognised that widespread and substantial increases in Dissolved organic carbon (DOC) concentrations in remote surface, and soil, waters in recent decades are linked to declining acid deposition. Effects of rising pH and declining ionic strength on DOC solubility have been proposed as potential dominant mechanisms. However, since DOC in these systems is derived mainly from recently-fixed carbon, and since organic matter decomposition rates are considered sensitive to temperature, uncertainty persists over the extent to which other drivers that could influence DOC production. Such potential drivers include fertilisation by nitrogen (N) and global warming. We therefore ran the dynamic soil chemistry model MADOC for a range of UK soils, for which time series data are available, to consider the likely relative importance of decreased deposition of sulphate and chloride, accumulation of reactive N, and higher temperatures, on soil DOC production in different soils. Modelled patterns of DOC change generally agreed favourably with measurements collated over 10-20years, but differed markedly between sites. While the acidifying effect of sulphur deposition appeared to be the predominant control on the observed soil water DOC trends in all the soils considered other than a blanket peat, the model suggested that over the long term, the effects of nitrogen deposition on N-limited soils may have been sufficient to raise the "acid recovery DOC baseline" significantly. In contrast, reductions in non-marine chloride deposition and effects of long term warming appeared to have been relatively unimportant. The suggestion that future DOC concentrations might exceed preindustrial levels as a consequence of nitrogen pollution has important implications for drinking water catchment management and the setting and pursuit of appropriate restoration targets, but findings still require validation from reliable centennial-scale proxy records, such as those being developed

  14. Medium-Term Renewable Energy Market Report 2013: Market trends and projections to 2018

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    Renewable electricity generation increased strongly worldwide in 2012, and deployment is occurring in a greater number of markets. However, the story of renewable energy development is becoming more complex. Short-term indicators in some regions of the globe have pointed to increased challenges. Despite remaining high, global new investment in renewable energy fell in 2012. Policy uncertainties, economic challenges, incentive reductions and competition from other energy sources clouded the investment outlook for some markets. Some countries and regions have faced difficulties in integrating variable renewables in their power grids. The renewable manufacturing industry, particularly solar and wind, entered a deeper period of restructuring and consolidation. Nevertheless, despite economic, policy and industry turbulence, the underlying fundamentals for renewable deployment remain robust. Even with challenges in some countries, more positive developments elsewhere continue to drive global growth. Competitive opportunities for renewables are emerging across traditional and new markets. While OECD countries remain a driver of renewable power development, non-OECD countries are increasingly accounting for overall growth. The roles of biofuels for transport and renewable heat are also increasing, though at somewhat slower rates than renewable electricity. The Medium-Term Renewable Energy Market Report 2013 assesses market trends for the renewable electricity, biofuels for transport and renewable heat sectors, identifying drivers and challenges to deployment, and making projections through 2018. The analysis features in-depth renewable electricity market analysis and forecasts for a slate of countries in the OECD and non-OECD. The report also presents an outlook for renewable electricity technologies, global biofuels supply, final energy use of renewables for heat and prospects for renewable investment.

  15. Lessons learned from Three Mile Island (TMI), USNRC long-term trends, industry response

    International Nuclear Information System (INIS)

    Szalay, R.A.

    1981-01-01

    Studies resulting from Three Mile Island (TMI) showed that corrections were needed in information processing, operator training and procedures, and certain aspects of the safety review process. These have been undertaken by industry and NRC and the results are positive. New safety instructions have been set up. The Nuclear Safety Analysis Center (NSAC) is providing a focus for analysis of issues which have generic elements affecting a number of plants of similar or related design. The Institute of Nuclear Power Operations (INPO) is setting industry standards for training and certification of operators and supervisory personnel, and for training of the managerial chain which oversees safety practices. Changes in procedures and in some design features called for in the recommendations of the NRC Lessons Learned Task Force (NUREG-0578) have been simplemented by utilities. Other requirements included in the NRC Action Plan (NUREG-0660) and its companion document clarification of TMI Action Plan Requirements (NUREG-0737), are also being addressed. Improved operator training and emergency procedures provide a continuing opportunity to make safety gains. Problems remain to be faced in the regulatory and political arenas. The long-term licensing trend will be affected by the manner in which degraded core issues and the development of a safety goal proceed. The Industry Degraded Core Rulemaking (IDCOR) program has been undertaken to develop the nuclear industry's position in anticipation of an impending rulemaking. Both industry and NRC are working on the development of a safety goal and standard risk assessment methodology. (AF)

  16. Short-term load forecast using trend information and process reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Santos, P.J.; Pires, A.J.; Martins, J.F. [Instituto Politecnico de Setubal (Portugal). Dept. of Electrical Engineering; Martins, A.G. [University of Coimbra (Portugal). Dept. of Electrical Engineering; Mendes, R.V. [Instituto Superior Tecnico, Lisboa (Portugal). Laboratorio de Mecatronica

    2005-07-01

    The algorithms for short-term load forecast (STLF), especially within the next-hour horizon, belong to a group of methodologies that aim to render more effective the actions of planning, operating and controlling electric energy systems (EES). In the context of the progressive liberalization of the electricity sector, unbundling of the previous monopolistic structure emphasizes the need for load forecast, particularly at the network level. Methodologies such as artificial neural networks (ANN) have been widely used in next-hour load forecast. Designing an ANN requires the proper choice of input variables, avoiding overfitting and an unnecessarily complex input vector (IV). This may be achieved by trying to reduce the arbitrariness in the choice of endogenous variables. At a first stage, we have applied the mathematical techniques of process-reconstruction to the underlying stochastic process, using coding and block entropies to characterize the measure and memory range. At a second stage, the concept of consumption trend in homologous days of previous weeks has been used. The possibility to include weather-related variables in the IV has also been analysed, the option finally being to establish a model of the non-weather sensitive type. The paper uses a real-life case study. (author)

  17. Short-term trends in the gas industry - Panorama 2008; Tendances a court terme de l'industrie gaziere - Panorama 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    In a context of high investment costs and rising energy prices, and recurring unseasonably warm temperatures in recent years, the growth of natural gas demand is slowing. On the supply side, and on the demand side too, new trends are emerging, with potentially powerful impact on the short-and long-term development of the industry.

  18. Accumulation of cadmium and zinc in soil and vegetation from long-term application of wastewater

    International Nuclear Information System (INIS)

    Hill, D.C.; Olson, B.H.; Rigby, M.G.

    1981-01-01

    The accumulation of Cd and Zn in soils and vegetation irrigated with treated sewage effluents was examined at 3 locations in southern California. The Whittier Narrows site, a groundwater recharge test plot, received secondary effluent through intermittent flooding for approximately 14 years. Fountain Valley, a forested site, was flood irrigated with both primary and secondary effluents for 16 years. The 3 Las Virgenes sites received various amounts of secondary effluent by spray irrigation for 8 years. Elevated levels of Cd and Zn were observed in the upper layers of soil at the Fountain Valley and Whittier Narrows sites. No metal accumulation from wastewater application was found at Las Virgenes. However, Cd was elevated throughout the soil profiles which reflected the Cd-enriched underlying host rock, Monterey Shale. A variety of weed species were examined at the Las Virgenes and Whittier Narrows sites and 4 tree species were studied at the Fountain Valley site. These results indicated that Cd and Zn concentrations in the tissue of most genera paralleled soil levels, but accumulation and exclusion patterns of Cd and Zn can be species dependent and therefore differ at the same site

  19. Water quality of the Neuse River, North Carolina - Variability, pollution loads, and long-term trends

    Science.gov (United States)

    Harned, Doughlas A.

    1982-01-01

    Interpretation of water-quality data collected by the U.S. Geological Survey for the Neuse River, North Carolina, has identified water-quality variations, charactrized the current condition of the river in reference to water-quality standards, estimated the degree of pollution caused by man, and evaluated long-term trends in concentrations of major dissolved constituents. Two sampling stations, Neuse River near Clayton (02087500) and Neuse River at Kinston (02089500) have more than 12 years of water-quality data collected during the period from 1955 to 1978. The Clayton station provides information on the upper fourth of the basin (1,129 mi 2) which includes several urbanized areas, including Raleigh, N.C., and part of Durham, N.C. The Kinston station provides information from the predominantly rural midsection of the basin (2,690 mi2). A network of temporary stations on small rural streams in the Neuse River and adjacent basins provide an estimate of baseline or es- sentially unpolluted water quality. Overall, the water quality of the Neuse River is satisfactory for most uses. However, dissolved-oxygen, iron, and manganese concentrations, pH, and bacterial concentrations often reach undesirable levels. Concentrations of cadmium, and lead also periodically peak at or above criterion levels for domestic water supply sources. Nutrient levels are generally high enough to allow rich algal growth. Sediment concentrations in the Neuse are high in comparison to pristine streams, however, the impacts of these high levels are difficult to quantify. Sediment and nutrient concentrations peak on the leading edge of flood discharges at Clayton. At Kinston, however, the discharge and sediment concentration peak almost simultaneously. Changes in algal dominance, from genera usually associated with organically enriched waters to genera that are less tolerant to organic enrichment, indicate improvement in water qualiy of the Neuse since 1973. These changes, along with a reduction

  20. Spatiotemporal distribution and short-term trends of particulate matter concentration over China, 2006-2010.

    Science.gov (United States)

    Yao, Ling; Lu, Ning

    2014-01-01

    Air quality problems caused by atmospheric particulate have drawn broad public concern in the global scope. In the paper, the spatiotemporal distributions of fine particle (PM2.5) and inhalable particle (PM10) concentrations estimated with the artificial neural network (ANN) over China during 2006 to 2010 have been discussed. Most high PM10 concentration appears in Xinjiang, Qinghai, Gansu, Ningxia, Hubei, and parts of Inner Mongolia. The distribution of PM2.5 concentration is consistent with China's three gradient terrains. The seasonal variations of PM2.5 and PM10 concentrations both indicate that they are higher in north China in spring and winter, lowest in summer. In autumn, most provinces in south China appear high value. In particular, high PM2.5 concentration appears in the southeast coastal cities while high PM10 concentration prefers the central regions in south China. On this basis, seasonal Mann-Kendall test method is utilized to analyze the short-term trends. The results also show significant changes of PM2.5 and PM10 concentrations of China in the past 5 years, and most provinces present the tendency of reduction (3-5 μg/m(3) for PM2.5 and 10-20 μg/m(3) for PM10 per year) while a fraction of provinces appear the increasing trend of 8-16 μg/m(3) (PM2.5) and 16-30 μg/m(3) (PM10). Simultaneously, PM2.5 population exposure is discussed with the combination of population density-gridded data. Municipalities get much higher exposure level than other provinces. Shanghai suffers the highest population exposure to PM2.5, followed by Beijing and then Tianjin, Jiangsu province. Most provincial capitals, such as Guangzhou, Nanjing, Chengdu, and Wuhan, face much higher exposure level than other regions of their province. Moreover, the PM2.5 exposure situation is more serious in southeast than northwest regions for Beijing-Tianjin-Hebei region. Also, per capita PM2.5 concentration and population-weighted PM2.5 concentration are calculated. The former shows that

  1. The long-term relationship between population growth and vegetation cover: an empirical analysis based on the panel data of 21 cities in Guangdong Province, China.

    Science.gov (United States)

    Li, Chao; Kuang, Yaoqiu; Huang, Ningsheng; Zhang, Chao

    2013-02-07

    It is generally believed that there is an inverse relationship between population growth and vegetation cover. However, reports about vegetation protection and reforestation around the World have been continuously increasing in recent decades, which seems to indicate that this relationship may not be true. In this paper, we have taken 21 cities in Guangdong Province, China as the study area to test the long-term relationship between population growth and vegetation cover, using an AVHRR NDVI data set and the panel cointegrated regression method. The results show that there is a long-term inverted N-shaped curve relationship between population growth and vegetation cover in the region where there are frequent human activities and the influence of climate change on vegetation cover changes is relatively small. The two turning points of the inverted N-shaped curve for the case of Guangdong Province correspond to 2,200 persons · km(-2) and 3,820 persons · km(-2), and they can provide a reference range for similar regions of the World. It also states that the population urbanization may have a negative impact on the vegetation cover at the early stage, but have a positive impact at the later stage. In addition, the Panel Error Correction Model (PECM) is used to investigate the causality direction between population growth and vegetation cover. The results show that not only will the consuming destruction effect and planting construction effect induced by the population growth have a great impact on vegetation cover changes, but vegetation cover changes in turn will also affect the population growth in the long term.

  2. The Long-Term Relationship between Population Growth and Vegetation Cover: An Empirical Analysis Based on the Panel Data of 21 Cities in Guangdong Province, China

    Directory of Open Access Journals (Sweden)

    Chao Li

    2013-02-01

    Full Text Available It is generally believed that there is an inverse relationship between population growth and vegetation cover. However, reports about vegetation protection and reforestation around the World have been continuously increasing in recent decades, which seems to indicate that this relationship may not be true. In this paper, we have taken 21 cities in Guangdong Province, China as the study area to test the long-term relationship between population growth and vegetation cover, using an AVHRR NDVI data set and the panel cointegrated regression method. The results show that there is a long-term inverted N-shaped curve relationship between population growth and vegetation cover in the region where there are frequent human activities and the influence of climate change on vegetation cover changes is relatively small. The two turning points of the inverted N-shaped curve for the case of Guangdong Province correspond to 2,200 persons·km−2 and 3,820 persons·km−2, and they can provide a reference range for similar regions of the World. It also states that the population urbanization may have a negative impact on the vegetation cover at the early stage, but have a positive impact at the later stage. In addition, the Panel Error Correction Model (PECM is used to investigate the causality direction between population growth and vegetation cover. The results show that not only will the consuming destruction effect and planting construction effect induced by the population growth have a great impact on vegetation cover changes, but vegetation cover changes in turn will also affect the population growth in the long term.

  3. Short-term vegetation response following mechanical control of saltcedar (Tamarix spp.) on the Virgin River, Nevada, USA

    Science.gov (United States)

    Ostoja, Steven M.; Brooks, Matthew L.; Dudley, Tom; Lee, Steven R.

    2014-01-01

    Tamarisk (a.k.a. saltcedar, Tamarix spp.) is an invasive plant species that occurs throughout western riparian and wetland ecosystems. It is implicated in alterations of ecosystem structure and function and is the subject of many local control projects, including removal using heavy equipment. We evaluated short-term vegetation responses to mechanical Tamarix spp. removal at sites ranging from 2 to 5 yr post-treatment along the Virgin River in Nevada, USA. Treatments resulted in lower density and cover (but not eradication) of Tamarix spp., increased cover of the native shrub Pluchea sericia (arrow weed), decreased density and cover of all woody species combined, increased density of both native annual forbs and the nonnative annual Salsola tragus (prickly Russian-thistle), and lower density of nonnative annual grasses. The treated plots had lower mean woody species richness, but greater herbaceous species richness and diversity. Among herbaceous species, native taxa increased in richness whereas nonnative species increased in both species richness and diversity. Thus, efforts to remove Tamarix,/i> spp. at the Virgin River reduced vegetative cover contributing to fuel loads and probability of fire, and resulted in positive effects for native plant diversity, with mixed effects on other nonnative species. However, absolute abundances of native species

  4. Medium-Term Oil Market Report 2012: Market Trends and Projections to 2017

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Supply shortfalls – from the Libyan civil war in 2011 and international sanctions on Iran in 2012 to a swathe of unplanned non-OPEC output stoppages – have buffeted the oil market, sending prices near 2008 highs and rekindling debate on the role of speculation in fuelling volatility. There have also been success stories. Growth in North American light, tight oil and non-conventional supply has reached game-changing levels. Iraqi production has scaled new heights, the Libyan production recovery in 2012 defied expectations and Saudi output surged to 30-year highs. On the demand front, the economic recovery has lost momentum. Market share continues to shift from mature to newly industrialised economies, but amid persistent concerns about the health of the former; China, the leading engine of oil demand growth of the last 15 years, is giving signs of slowdown. Those developments have challenged earlier assumptions and significantly changed the oil market outlook for the next five years. The IEA Medium-Term Oil Market Report (MTOMR) – companion to the monthly OMR – draws their implications for the future. It provides detailed projections for oil supply at field level, crude quality trends, demand by product, refined product output and oil investments through 2017. It examines oil price formation, regulatory changes, OPEC dynamics and the future of spare capacity – while also reviewing the contribution of new supplies from deepwater, light tight oil, biofuel and natural gas liquids. It explores how market changes are reshaping the refining industry – and what that means for trade flows. At a time of heightened economic and geopolitical risk, MTOMR is essential reading for anyone interested in oil market dynamics and in understanding the oil market context in which these risks are playing out.

  5. Long-term Trends in Particulate Organic Carbon from a Low-Gradient Autotrophic Watershed

    Science.gov (United States)

    Fox, J.; Ford, W. I., III

    2014-12-01

    Recent insights from low-gradient streams dominated by fine surficial sediments have shown fluvial organic matter dynamics are governed by coupled hydrologic and biotic controls at event to seasonal timescales. Notwithstanding the importance of shorter timescales, quantity and quality of carbon in stream ecosystems at annual and decadal scales is of increased interest in order to understand if stream ecosystems are net stores or sinks of carbon and how stream carbon behaves under dynamic climate conditions. As part of an ongoing study in a low-gradient, agricultural watershed in the Bluegrass Region of Central Kentucky, an eight year dataset of transported particulate organic carbon (POC) was analyzed for the present study. The objective was to investigate if POC dynamics at multi-year timescales are governed by biotic or hydrologic processes. A statistical analysis using Empirical Mode Decomposition was performed on an 8 year dataset of transported sediment carbon, temperature, and log-transformed flowrates at the watershed outlet. Simulations from a previously validated, process-based, organic carbon model were utilized as further verification of drivers. Results from the analysis suggest that a 4 degree Celsius mean annual temperature shift corresponds to a 63% increase in organic carbon content at the main-stem, third order outlet and a 33% increase in organic carbon content at the main-stem inlet. Model and stable isotope results for the 8 year study support that long-term increases in organic carbon concentration are governed by biotic growth and humification of algal biomass in which increasing annual temperatures promote increased organic carbon production, relative to ecosystem respiration. This result contradicts conventional wisdom, suggesting projected warming trends will shift autotrophic freshwater systems to net heterotrophic, which has significant implications for the role of benthic stream ecosystems under changing climate conditions. Future work

  6. Long-term trends in foF2: their estimating and origin

    Directory of Open Access Journals (Sweden)

    W. Wan

    2008-03-01

    Full Text Available This paper deals with two problems, methods of foF2 trend determination and origin of trends in foF2, both being controversial in current literature. We found that various regression-based methods and artificial neural network-based method of Yue et al. (2006 provided comparable results within uncertainties caused mainly by various ways of removing/suppressing the dominant solar cycle effect. The role of geomagnetic activity in the observed trends in foF2 was probably substantial and might be still even rather dominant in the last quarter of the 20th century.

  7. Elderly and long-term care trends and policy in Taiwan: Challenges and opportunities for health care professionals

    Directory of Open Access Journals (Sweden)

    Hsiu-Hung Wang

    2012-09-01

    Full Text Available The purpose of this article is to address the trends and policy of elderly and long-term care in Taiwan. In response to the increasing demand of an aging society, healthcare professionals play crucial roles in elderly and long-term care and quality assurance of services. This article focuses on the current situation of elderly health care, demands of long-term care, long-term care policy in Taiwan, draft of the Long-term Care Services Act, and draft of the Long-term Care Insurance Act. After the 10-year long-term care project was proposed by the Taiwan government, the supply of health care services and demand for long-term care have created many challenges and opportunities for innovative health professional development. Challenges consist of low old dependency ratio caused by low birth rate, lack of elderly and long-term care related manpower, services and education reform related to long-term care for the future society, and interprofessional collaboration and team work of long-term care. Opportunities include expanding the roles and the career pathways of healthcare professionals, promoting the concepts of active aging and good quality of life, and developing industrial cooperation related to long-term care services. Under these circumstances, healthcare professonals are actively involved in practice, education and research of long-term care services that ensure elderly and disabled people can live a healthier and better life.

  8. Spatial and temporal trends in runoff at long-term streamgages within and near the Chesapeake Bay Watershed

    Science.gov (United States)

    Rice, Karen C.; Hirsch, Robert M.

    2012-01-01

    Long-term streamflow data within the Chesapeake Bay watershed and surrounding area were analyzed in an attempt to identify trends in streamflow. Data from 30 streamgages near and within the Chesapeake Bay watershed were selected from 1930 through 2010 for analysis. Streamflow data were converted to runoff and trend slopes in percent change per decade were calculated. Trend slopes for three runoff statistics (the 7-day minimum, the mean, and the 1-day maximum) were analyzed annually and seasonally. The slopes also were analyzed both spatially and temporally. The spatial results indicated that trend slopes in the northern half of the watershed were generally greater than those in the southern half. The temporal analysis was done by splitting the 80-year flow record into two subsets; records for 28 streamgages were analyzed for 1930 through 1969 and records for 30 streamgages were analyzed for 1970 through 2010. The mean of the data for all sites for each year were plotted so that the following datasets were analyzed: the 7-day minimum runoff for the north, the 7-day minimum runoff for the south, the mean runoff for the north, the mean runoff for the south, the 1-day maximum runoff for the north, and the 1-day maximum runoff for the south. Results indicated that the period 1930 through 1969 was statistically different from the period 1970 through 2010. For the 7-day minimum runoff and the mean runoff, the latter period had significantly higher streamflow than did the earlier period, although within those two periods no significant linear trends were identified. For the 1-day maximum runoff, no step trend or linear trend could be shown to be statistically significant for the north, although the south showed a mixture of an upward step trend accompanied by linear downtrends within the periods. In no case was a change identified that indicated an increasing rate of change over time, and no general pattern was identified of hydrologic conditions becoming "more extreme

  9. Health Care Cost Growth and Demographic Trends Drive the Long-Term Fiscal Challenge

    National Research Council Canada - National Science Library

    2008-01-01

    ... health care costs and known demographic trends. In fact, the oldest members of the baby boom generation are now eligible for Social Security retirement benefits and will be eligible for Medicare benefits in less than 3 years...

  10. Climate-vegetation-fire interactions and their impact on long-term carbon dynamics in a boreal peatland landscape in northern Manitoba, Canada

    Science.gov (United States)

    Camill, Philip; Barry, Ann; Williams, Evie; Andreassi, Christian; Limmer, Jacob; Solick, Donald

    2009-12-01

    Climate warming may increase the size and frequency of fires in the boreal biome, possibly causing greater carbon release that amplifies warming. However, in peatlands, vegetation change may also control long-term fire and carbon accumulation, confounding simple relationships between climate, fire, and carbon accumulation. Using 17 peat cores dating to 8000 cal years B.P. from northern Manitoba, Canada, we addressed the following questions: (1) Do past climate changes correlate with shifts in peatland vegetation? (2) What is the relationship between peatland vegetation and fire severity? (3) What is the mean return interval for boreal peat fires, and how does it change across fires of different severities? (4) How does fire severity affect carbon accumulation rates? (5) Do fire and long-term carbon accumulation change directly in response to climate or indirectly though climate-driven changes in vegetation? We measured carbon accumulation rates, fire severity, and return intervals using macroscopic charcoal and changes in vegetation using macrofossils. Climate and vegetation changes covaried, with shifts from wetter fen to drier, forested bog communities during the Holocene Thermal Maximum (HTM). Fires became more severe following the shift to forested bogs, with fire severity peaking after 4000 cal years B.P. rather than during the HTM. Rising fire severity, in turn, was correlated with a significant decrease in carbon accumulation from ˜6000 to 2000 cal years B.P. The Medieval Warm Period and Little Ice Age affected vegetation composition and permafrost, further impacting fire and carbon accumulation. Our results indicate that long-term changes in fire and carbon dynamics are mediated by climate-driven changes in vegetation.

  11. Long‐term trends in fall age ratios of black brant

    Science.gov (United States)

    Ward, David H.; Amundson, Courtney L.; Stehn, Robert A.; Dau, Christian P.

    2018-01-01

    Accurate estimates of the age composition of populations can inform past reproductive success and future population trajectories. We examined fall age ratios (juveniles:total birds) of black brant (Branta bernicla nigricans; brant) staging at Izembek National Wildlife Refuge near the tip of the Alaska Peninsula, southwest Alaska, USA, 1963 to 2015. We also investigated variation in fall age ratios associated with sampling location, an index of flock size, survey effort, day of season, observer, survey platform (boat‐ or land‐based) and tide stage. We analyzed data using logistic regression models implemented in a Bayesian framework. Mean predicted fall age ratio controlling for survey effort, day of year, and temporal and spatial variation was 0.24 (95% CL = 0.23, 0.25). Overall trend in age ratios was −0.6% per year (95% CL = −1.3%, 0.2%), resulting in an approximate 26% decline in the proportion of juveniles over the study period. We found evidence for variation across a range of variables implying that juveniles are not randomly distributed in space and time within Izembek Lagoon. Age ratios varied by location within the study area and were highly variable among years. They decreased with the number of birds aged (an index of flock size) and increased throughout September before leveling off in early October and declining in late October. Age ratios were similar among tide stages and observers and were lower during boat‐based (offshore) than land‐based (nearshore) surveys. Our results indicate surveys should be conducted annually during early to mid‐October to ensure the entire population is present and available for sampling, and throughout Izembek Lagoon to account for spatiotemporal variation in age ratios. Sampling should include a wide range of flock sizes representative of their distribution and occur in flocks located near and off shore. Further research evaluating the cause of declining age ratios in the fall population is necessary

  12. Factors challenging our ability to detect long-term trends in ocean chlorophyll

    Directory of Open Access Journals (Sweden)

    C. Beaulieu

    2013-04-01

    Full Text Available Global climate change is expected to affect the ocean's biological productivity. The most comprehensive information available about the global distribution of contemporary ocean primary productivity is derived from satellite data. Large spatial patchiness and interannual to multidecadal variability in chlorophyll a concentration challenges efforts to distinguish a global, secular trend given satellite records which are limited in duration and continuity. The longest ocean color satellite record comes from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS, which failed in December 2010. The Moderate Resolution Imaging Spectroradiometer (MODIS ocean color sensors are beyond their originally planned operational lifetime. Successful retrieval of a quality signal from the current Visible Infrared Imager Radiometer Suite (VIIRS instrument, or successful launch of the Ocean and Land Colour Instrument (OLCI expected in 2014 will hopefully extend the ocean color time series and increase the potential for detecting trends in ocean productivity in the future. Alternatively, a potential discontinuity in the time series of ocean chlorophyll a, introduced by a change of instrument without overlap and opportunity for cross-calibration, would make trend detection even more challenging. In this paper, we demonstrate that there are a few regions with statistically significant trends over the ten years of SeaWiFS data, but at a global scale the trend is not large enough to be distinguished from noise. We quantify the degree to which red noise (autocorrelation especially challenges trend detection in these observational time series. We further demonstrate how discontinuities in the time series at various points would affect our ability to detect trends in ocean chlorophyll a. We highlight the importance of maintaining continuous, climate-quality satellite data records for climate-change detection and attribution studies.

  13. The role of tectonic uplift, climate, and vegetation in the long-term terrestrial phosphorous cycle

    Directory of Open Access Journals (Sweden)

    C. Buendía

    2010-06-01

    Full Text Available Phosphorus (P is a crucial element for life and therefore for maintaining ecosystem productivity. Its local availability to the terrestrial biosphere results from the interaction between climate, tectonic uplift, atmospheric transport, and biotic cycling. Here we present a mathematical model that describes the terrestrial P-cycle in a simple but comprehensive way. The resulting dynamical system can be solved analytically for steady-state conditions, allowing us to test the sensitivity of the P-availability to the key parameters and processes. Given constant inputs, we find that humid ecosystems exhibit lower P availability due to higher runoff and losses, and that tectonic uplift is a fundamental constraint. In particular, we find that in humid ecosystems the biotic cycling seem essential to maintain long-term P-availability. The time-dependent P dynamics for the Franz Josef and Hawaii chronosequences show how tectonic uplift is an important constraint on ecosystem productivity, while hydroclimatic conditions control the P-losses and speed towards steady-state. The model also helps describe how, with limited uplift and atmospheric input, as in the case of the Amazon Basin, ecosystems must rely on mechanisms that enhance P-availability and retention. Our novel model has a limited number of parameters and can be easily integrated into global climate models to provide a representation of the response of the terrestrial biosphere to global change.

  14. Geomagnetic and ionospheric data analysis over Antarctica: a contribution to the long term trends investigation

    Directory of Open Access Journals (Sweden)

    L. Alfonsi

    2008-05-01

    Full Text Available The analysis of the foF2 ionosonde data acquired at mid and high latitudes reveals a general decreasing of the F2 plasma frequency over more than two solar cycles, showing steeper trends over the high latitude stations and, in particular, over Antarctica. A careful analysis of the foF2 hourly data, opportunely catalogued in different levels of magneto-ionospheric conditions, highlights the role of the geomagnetic activity in the secular change of the ionosphere and confirms the latitudinal dependence of the trends. These results suggest interesting relations with some recent findings on the rapid decrease of some important physical and statistical quantities related to the geomagnetic field over the whole globe and mainly in Antarctica. In this paper we discuss the possibility of a connection between the ionospheric trends and a possible imminent geomagnetic reversal or excursion.

  15. Geomagnetic and ionospheric data analysis over Antarctica: a contribution to the long term trends investigation

    Directory of Open Access Journals (Sweden)

    L. Alfonsi

    2008-05-01

    Full Text Available The analysis of the foF2 ionosonde data acquired at mid and high latitudes reveals a general decreasing of the F2 plasma frequency over more than two solar cycles, showing steeper trends over the high latitude stations and, in particular, over Antarctica. A careful analysis of the foF2 hourly data, opportunely catalogued in different levels of magneto-ionospheric conditions, highlights the role of the geomagnetic activity in the secular change of the ionosphere and confirms the latitudinal dependence of the trends. These results suggest interesting relations with some recent findings on the rapid decrease of some important physical and statistical quantities related to the geomagnetic field over the whole globe and mainly in Antarctica. In this paper we discuss the possibility of a connection between the ionospheric trends and a possible imminent geomagnetic reversal or excursion.

  16. Calibration Uncertainty in Ocean Color Satellite Sensors and Trends in Long-term Environmental Records

    Science.gov (United States)

    Turpie, Kevin R.; Eplee, Robert E., Jr.; Franz, Bryan A.; Del Castillo, Carlos

    2014-01-01

    Launched in late 2011, the Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the Suomi National Polar-orbiting Partnership (NPP) spacecraft is being evaluated by NASA to determine whether this sensor can continue the ocean color data record established through the Sea-Viewing Wide Field-of-view Sensor (SeaWiFS) and the MODerate resolution Imaging Spectroradiometer (MODIS). To this end, Goddard Space Flight Center generated evaluation ocean color data products using calibration techniques and algorithms established by NASA during the SeaWiFS and MODIS missions. The calibration trending was subjected to some initial sensitivity and uncertainty analyses. Here we present an introductory assessment of how the NASA-produced time series of ocean color is influenced by uncertainty in trending instrument response over time. The results help quantify the uncertainty in measuring regional and global biospheric trends in the ocean using satellite remote sensing, which better define the roles of such records in climate research.

  17. On the role of solar and geomagnetic activity in long-term trends in the atmosphere-ionosphere system

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan

    2005-01-01

    Roč. 67, č. 1-2 (2005), s. 83-92 ISSN 1364-6826 R&D Projects: GA AV ČR KSK3012103; GA AV ČR IAA3042102 Institutional research plan: CEZ:AV0Z30420517 Keywords : Long-term trends * Atmosphere * Ionosphere * Solar activity * Geomagnetic activity Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.309, year: 2005

  18. Long term climatology and trends of heat and cold waves over ...

    Indian Academy of Sciences (India)

    at the rate 0.15 and 0.17 per year, respectively, with significance at 95% confidence level. Zone-IIIB on ... ever, few stations have shown significant decreasing trends in heat ..... per hectare) have been tested and were found best for resilience ...

  19. Thinning method and intensity influence long-term mortality trends in a red pine forest

    Science.gov (United States)

    Matthew D. Powers; Brian J. Palik; John B. Bradford; Shawn Fraver; Christopher R. Webster

    2010-01-01

    Tree mortality shapes forest development, but rising mortality can represent lost production or an adverse response to changing environmental conditions. Thinning represents a strategy for reducing mortality rates, but different thinning techniques and intensities could have varying impacts depending on how they alter stand structure. We analyzed trends in stand...

  20. Detection of field significant long-term monotonic trends in spring yields

    Czech Academy of Sciences Publication Activity Database

    Ledvinka, O.; Lamačová, Anna

    2015-01-01

    Roč. 29, č. 5 (2015), s. 1463-1484 ISSN 1436-3240 Institutional support: RVO:67179843 Keywords : Cross-correlation * Groundwater monitoring * Serial correlation * Spring yields * Trend analysis Subject RIV: DA - Hydrology ; Limnology OBOR OECD: Hydrology Impact factor: 2.237, year: 2015

  1. Long-term citizen-collected data reveal geographical patterns and temporal trends in lake water clarity

    Science.gov (United States)

    Lottig, Noah R.; Wagner, Tyler; Henry, Emily N.; Cheruvelil, Kendra Spence; Webster, Katherine E.; Downing, John A.; Stow, Craig A.

    2014-01-01

    We compiled a lake-water clarity database using publically available, citizen volunteer observations made between 1938 and 2012 across eight states in the Upper Midwest, USA. Our objectives were to determine (1) whether temporal trends in lake-water clarity existed across this large geographic area and (2) whether trends were related to the lake-specific characteristics of latitude, lake size, or time period the lake was monitored. Our database consisted of >140,000 individual Secchi observations from 3,251 lakes that we summarized per lake-year, resulting in 21,020 summer averages. Using Bayesian hierarchical modeling, we found approximately a 1% per year increase in water clarity (quantified as Secchi depth) for the entire population of lakes. On an individual lake basis, 7% of lakes showed increased water clarity and 4% showed decreased clarity. Trend direction and strength were related to latitude and median sample date. Lakes in the southern part of our study-region had lower average annual summer water clarity, more negative long-term trends, and greater inter-annual variability in water clarity compared to northern lakes. Increasing trends were strongest for lakes with median sample dates earlier in the period of record (1938–2012). Our ability to identify specific mechanisms for these trends is currently hampered by the lack of a large, multi-thematic database of variables that drive water clarity (e.g., climate, land use/cover). Our results demonstrate, however, that citizen science can provide the critical monitoring data needed to address environmental questions at large spatial and long temporal scales. Collaborations among citizens, research scientists, and government agencies may be important for developing the data sources and analytical tools necessary to move toward an understanding of the factors influencing macro-scale patterns such as those shown here for lake water clarity.

  2. Long-Term Trends in Nutrient Concentrations and Fluxes in Streams Draining to Lake Tahoe, California

    Science.gov (United States)

    Domagalski, J. L.

    2017-12-01

    Lake Tahoe, situated in the rain shadow of the eastern Sierra Nevada at an elevation of 1,897 meters, has numerous small to medium sized tributaries that are sources of nutrients and fine sediment. The Tahoe watershed is relatively small and the surface area of the lake occupies about 38% of the total watershed area (1,313 km2). Each stream contributing water to the lake therefore also occupies a small watershed, mostly forested, with typical trees being Jeffrey, Ponderosa, or Sugar Pine and White Fir. Outflow from the lake contributes to downstream uses such as water supply and ecological resources. Only about 6% of the watershed is urbanized or residential land, and wastewater is exported to adjacent basins and not discharged to the lake as part of a plan to maintain water clarity. The lake's exceptional clarity has been diminishing due to phytoplankton and fine sediment, prompting development of management plans to improve water quality. Much of the annual discharge and flux of nutrients to the lake results from snowmelt in the spring and summer months, and climatic changes have begun to shift this melt to earlier time frames. Winter rains on urbanized land also contribute to nutrient loads. To understand the relative importance of land use, climate, and other factors affecting stream concentrations and fluxes, a Weighted Regression on Time Discharge and Season (WRTDS) model documented trends over a time frame of greater than 25 years. Ten streams have records of discharge, nutrient (NO3, NH3, OP, TP, TKN) and sediment data to complete this analysis. Both urbanized and non-urbanized locations generally show NO3 trending down in the 1980s. Some locations show initially decreasing orthophosphate trends, followed by small significant increases in concentration and fluxes starting around 2000 to 2005. Although no wastewater enters the streams, ammonia concentrations mimic those of orthophosphate, with initially negative trends in concentration and flux followed by

  3. Effects of organic matter removal, soil compaction, and vegetation control on 5-year seedling performance: a regional comparison of long-term soil productivity sites

    Science.gov (United States)

    Robert L. Fleming; Robert F. Powers; Neil W. Foster; J. Marty Kranabetter; D. Andrew Scott; Felix Jr. Ponder; Shannon Berch; William K. Chapman; Richard D. Kabzems; Kim H. Ludovici; David M. Morris; Deborah S. Page-Dumroese; Paul T. Sanborn; Felipe G. Sanchez; Douglas M. Stone; Allan E. Tiarks

    2006-01-01

    We examined fifth-year seedling response to soil disturbance and vegetation control at 42 experimental locations representing 25 replicated studies within the North American Long-Term Soil Productivity (LTSP) program. These studies share a common experimental design while encompassing a wide range of climate, site conditions, and forest types. Whole-tree harvest had...

  4. A Lagrangian analysis of mid-latitude stratospheric ozone variability and long-term trends.

    Science.gov (United States)

    Koch, G.; Wernli, H.; Staehelin, J.; Peter, T.

    2002-05-01

    A systematic Lagrangian investigation is performed of wintertime high-resolution stratospheric ozone soundings at Payerne, Switzerland, from January 1970 to March 2001. For every ozone sounding, 10-day backward trajectories have been calculated on 16 isentropic levels using NCEP reanalysis data. Both the minimum/maximum latitude and potential vorticity (PV) averaged along the trajectories are used as indicators of the air parcels' ``origin''. The importance of transport for the understandin g of single ozone profiles is confirmed by a statistical analysis which shows that negative/positive ozone deviations gener ally coincide with transport from regions with climatologically low/high ozone values. The stable relationship between PV and ozone for the 32 year period indicates either no direct chemical impact or no temporal change of this impact. In the upper layer the PV-ozone relationship changes significantly after 1987 and a separate trend analysis for air masses transported from the polar, midlatitude and subtropical regions shows negative ozone trends in all three categories (with a maximum for the polar region). This is not direct evidence for, but would be in agreement with, an increased chemical ozone depletion in the Arctic since the late 1980s. The reasons for the negative trend in the mid-stratospheric air masses with subtropical origin that are in qualitative agreement with recent satellite observations are presently unknown.

  5. Historical trends and the long-term changes of the hydrological cycle components in a Mediterranean river basin.

    Science.gov (United States)

    Mentzafou, A; Wagner, S; Dimitriou, E

    2018-04-29

    Identifying the historical hydrometeorological trends in a river basin is necessary for understanding the dominant interactions between climate, human activities and local hydromorphological conditions. Estimating the hydrological reference conditions in a river is also crucial for estimating accurately the impacts from human water related activities and design appropriate water management schemes. In this effort, the output of a regional past climate model was used, covering the period from 1660 to 1990, in combination with a dynamic, spatially distributed, hydrologic model to estimate the past and recent trends in the main hydrologic parameters such as overland flow, water storages and evapotranspiration, in a Mediterranean river basin. The simulated past hydrologic conditions (1660-1960) were compared with the current hydrologic regime (1960-1990), to assess the magnitude of human and natural impacts on the identified hydrologic trends. The hydrological components of the recent period of 2008-2016 were also examined in relation to the impact of human activities. The estimated long-term trends of the hydrologic parameters were partially assigned to varying atmospheric forcing due to volcanic activity combined with spontaneous meteorological fluctuations. Copyright © 2018. Published by Elsevier B.V.

  6. Long-term trends in California mobile source emissions and ambient concentrations of black carbon and organic aerosol.

    Science.gov (United States)

    McDonald, Brian C; Goldstein, Allen H; Harley, Robert A

    2015-04-21

    A fuel-based approach is used to assess long-term trends (1970-2010) in mobile source emissions of black carbon (BC) and organic aerosol (OA, including both primary emissions and secondary formation). The main focus of this analysis is the Los Angeles Basin, where a long record of measurements is available to infer trends in ambient concentrations of BC and organic carbon (OC), with OC used here as a proxy for OA. Mobile source emissions and ambient concentrations have decreased similarly, reflecting the importance of on- and off-road engines as sources of BC and OA in urban areas. In 1970, the on-road sector accounted for ∼90% of total mobile source emissions of BC and OA (primary + secondary). Over time, as on-road engine emissions have been controlled, the relative importance of off-road sources has grown. By 2010, off-road engines were estimated to account for 37 ± 20% and 45 ± 16% of total mobile source contributions to BC and OA, respectively, in the Los Angeles area. This study highlights both the success of efforts to control on-road emission sources, and the importance of considering off-road engine and other VOC source contributions when assessing long-term emission and ambient air quality trends.

  7. Long-term trends in nitrogen isotope composition and nitrogen concentration in brazilian rainforest trees suggest changes in nitrogen cycle.

    Science.gov (United States)

    Hietz, Peter; Dünisch, Oliver; Wanek, Wolfgang

    2010-02-15

    Direct or indirect anthropogenic effects on ecosystem nitrogen cycles are important components of global change. Recent research has shown that N isotopes in tree rings reflect changes in ecosystem nitrogen sources or cycles and can be used to study past changes. We analyzed trends in two tree species from a remote and pristine tropical rainforest in Brazil, using trees of different ages to distinguish between the effect of tree age and long-term trends. Because sapwood differed from heartwood in delta(15)N and N concentration and N can be translocated between living sapwood cells, long-term trends are best seen in dead heartwood. Heartwood delta(15)N in Spanish cedar (Cedrela odorata) and big-leaf mahogany (Swietenia macrophylla) increased with tree age, and N concentrations increased with age in Cedrela. Controlling for tree age, delta(15)N increased significantly during the past century even when analyzing only heartwood and after removing labile N compounds. In contrast to northern temperate and boreal forests where wood delta(15)N often decreased, the delta(15)N increase in a remote rainforest is unlikely to be a direct signal of changed N deposition. More plausibly, the change in N isotopic composition indicates a more open N cycle, i.e., higher N losses relative to internal N cycling in the forest, which could be the result of changed forest dynamics.

  8. Long-term energy balance and vegetation water stress monitoring of Mediterranean oak savanna using satellite thermal data

    Science.gov (United States)

    González-Dugo, Maria P.; Chen, Xuelong; Andreu, Ana; Carpintero, Elisabet; Gómez-Giraldez, Pedro; Su, Z.(Bob)

    2017-04-01

    Drought is one of the major hazards faced by natural and cropped vegetation in the Mediterranean Sea Basin. Water scarcity is likely to be worsened under the predicted conditions of climate change, which is expected to make this region both warmer and drier. A Holm oak savanna, known as dehesa in Spain and montado in Portugal, is an agro-silvo-pastoral system occupying more than 3 million hectares the Iberian Peninsula and Greece. It consists of widely-spaced oak trees (mostly Quercus ilex L.), combined with crops, pasture and Mediterranean shrubs. This ecosystem is considered an example of sustainable land use, supporting a large number of species and diversity of habitats and for its importance in rural economy. A similar ecosystem is worldwide distributed in areas with Mediterranean climate (as California or South Africa) and shares structural and functional properties with tropical savannas in Africa, Australia and South America. Remote sensing time series can assist the monitoring of the energy balance components, with special attention to the evapotranspiration and vegetation water stress over these areas. Long-term data analysis may improve our understanding of the functioning of the system, helping to assess drought impacts and leading to reduce the economic and environmental vulnerability of this ecosystem. This work analyzes the evolution the surface energy balance components, mapping the evapotranspiration and moisture stress of holm oak woodlands of Spain and Portugal during the last 15 years (2001-2015). The surface energy balance model (SEBS) has been applied over the Iberian Peninsula on a monthly time scale and 0.05° spatial resolution, using multi-satellite and meteorological forcing data. Modelled energy and water fluxes have been validated using ground measurements of two eddy covariance towers located in oak savanna sites during 3 years, resulting in moderate deviations from observations (10-25 W/m2). The departure of actual ET from the

  9. Long-term trends in the abundance and community structure of ...

    African Journals Online (AJOL)

    ... increased predation by top predators. Another mechanism contributing to the long-term increase in zooplankton is the observed long-term intensification of coastal upwelling, which could enhance primary and secondary production, and increase advective input of zooplankton populations into the study area and augment ...

  10. Prevalent Long-Term Trends of Hypertension in Austria: The Impact of Obesity and Socio-Demography.

    Directory of Open Access Journals (Sweden)

    Franziska Großschädl

    Full Text Available Globally there are only less long-term-studies on hypertension available to provide reliable estimates and identify risk groups. This study aims to analyse the prevalence and long-term-trend of hypertension in Austria, recognize affected subpopulations and investigate social inequalities.This representative population-based study is based on self-reported data of adults (mean age: 47.7 ± 17.5; n = 178,818 that were taken from five health surveys between 1973 and 2007. An adjustment of self-reported BMI was performed based on a preliminary validation study. Absolute changes (AC and aetiologic fractions (AF were calculated from logistic regressions in order to measure trends. To quantify the extent of social inequality, a relative index of inequality (RII was computed.During the study period the age-standardized hypertension prevalence increased from 1.0% to 18.8%, with a considerable rise from 1991 onwards. There was a positive trend in all subpopulations, with the highest AC among obese women (+50.2% and obese subjects aged 75 years and older (+54.4%, whereas the highest risk was observed among the youngest obese adults (AF: 99.4%. The RII for hypertension was higher for women than men, but in general unstable during the investigation period.Obesity and older age are significant factors for increased morbidity of hypertension. The most undesirable trends occurred in obese women and obese subjects aged 75 years and older. These risk groups should be given special attention when planning hypertension prevention programs. The high increase in the prevalence of hypertension is due to different aspects, e.g. a demographic change and a change in the definition of hypertension. These findings help to understand why hypertension is becoming more common in the Austrian population.

  11. Coping with climate variability and long-term climate trends for Nicaraguan maize-bean farmers (Invited)

    Science.gov (United States)

    Gourdji, S.; Zelaya Martinez, C.; Martinez Valle, A.; Mejia, O.; Laderach, P.; Lobell, D. B.

    2013-12-01

    Climate variability and change impact farmers at different timescales, but both are of concern for livelihoods and long-term viability of small farms in tropical, rain-fed agricultural systems. This study uses a historical dataset to analyze the impact of 40-year climate trends in Nicaragua on bean production, a staple crop that is an important source of calories and protein in the local diet, particularly in rural areas and in lower income classes. Bean yields are sensitive to rising temperatures, but also frequently limited by seasonal drought and low soil fertility. We use an empirical model to relate department-level yields to spatial variation and inter-annual fluctuations in historical precipitation, temperature and extreme rain events. We then use this model to quantify the impact on yields of long-term observed warming in day and night temperatures, increases in rainfall intensity, longer gaps between rain events, a shorter rainy season and overall drying in certain regions of the country. Preliminary results confirm the negative impacts of warming night temperatures, higher vapor pressure deficits, and longer gaps between rain events on bean yields, although some drying at harvest time has helped to reduce rotting. Across all bean-growing areas, these climate trends have led to a ~10% yield decline per decade relative to a stationary climate and production system, with this decline reaching up to ~20% in the dry northern highlands. In regions that have been particularly impacted by these trends, we look for evidence of farm abandonment, increases in off-farm employment, or on-farm adaptation solutions through crop diversification, use of drought or heat-tolerant seed, and adoption of rainwater harvesting. We will also repeat the modeling exercise for maize, another staple crop providing ~25% of daily calories at the national scale, but which is projected to be more resilient to climate trends.

  12. Black Carbon and Sulfate Aerosols in the Arctic: Long-term Trends, Radiative Impacts, and Source Attributions

    Science.gov (United States)

    Wang, H.; Zhang, R.; Yang, Y.; Smith, S.; Rasch, P. J.

    2017-12-01

    The Arctic has warmed dramatically in recent decades. As one of the important short-lived climate forcers, aerosols affect the Arctic radiative budget directly by interfering radiation and indirectly by modifying clouds. Light-absorbing particles (e.g., black carbon) in snow/ice can reduce the surface albedo. The direct radiative impact of aerosols on the Arctic climate can be either warming or cooling, depending on their composition and location, which can further alter the poleward heat transport. Anthropogenic emissions, especially, BC and SO2, have changed drastically in low/mid-latitude source regions in the past few decades. Arctic surface observations at some locations show that BC and sulfate aerosols had a decreasing trend in the recent decades. In order to understand the impact of long-term emission changes on aerosols and their radiative effects, we use the Community Earth System Model (CESM) equipped with an explicit BC and sulfur source-tagging technique to quantify the source-receptor relationships and decadal trends of Arctic sulfate and BC and to identify variations in their atmospheric transport pathways from lower latitudes. The simulation was conducted for 36 years (1979-2014) with prescribed sea surface temperatures and sea ice concentrations. To minimize potential biases in modeled large-scale circulations, wind fields in the simulation are nudged toward an atmospheric reanalysis dataset, while atmospheric constituents including water vapor, clouds, and aerosols are allowed to evolve according to the model physics. Both anthropogenic and open fire emissions came from the newly released CMIP6 datasets, which show strong regional trends in BC and SO2 emissions during the simulation time period. Results show that emissions from East Asia and South Asia together have the largest contributions to Arctic sulfate and BC concentrations in the upper troposphere, which have an increasing trend. The strong decrease in emissions from Europe, Russia and

  13. Long-term trends in total inorganic nitrogen and sulfur deposition in the US from 1990 to 2010

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2018-06-01

    Full Text Available Excess deposition (including both wet and dry deposition of nitrogen and sulfur is detrimental to ecosystems. Recent studies have investigated the spatial patterns and temporal trends of nitrogen and sulfur wet deposition, but few studies have focused on dry deposition due to the scarcity of dry deposition measurements. Here, we use long-term model simulations from the coupled Weather Research and Forecasting and the Community Multiscale Air Quality (WRF-CMAQ model covering the period from 1990 to 2010 to study changes in spatial distribution as well as temporal trends in total (TDEP, wet (WDEP, and dry deposition (DDEP of total inorganic nitrogen (TIN and sulfur (TS in the United States (US. We first evaluate the model's performance in simulating WDEP over the US by comparing the model results with observational data from the US National Atmospheric Deposition Program. The coupled model generally underestimates the WDEP of both TIN (including both the oxidized nitrogen deposition, TNO3, and the reduced nitrogen deposition, NHx and TS, with better performance in the eastern US than the western US. The underestimation of the wet deposition by the model is mainly caused by the coarse model grid resolution, missing lightning NOx emissions, and the poor temporal and spatial representation of NH3 emissions. TDEP of both TIN and TS shows significant decreases over the US, especially in the east, due to the large emission reductions that occurred in that region. The decreasing trends of TIN TDEP are caused by decreases in TNO3, and the increasing trends of TIN deposition over the Great Plains and Tropical Wet Forests (Southern Florida Coastal Plain regions are caused by increases in NH3 emissions, although it should be noted that these increasing trends are not significant. TIN WDEP shows decreasing trends throughout the US, except for the Marine West Coast Forest region. TIN DDEP shows significant decreasing trends in the Eastern Temperate Forests

  14. Long-term trends in child and youth injury mortality in Taiwan, 1989-2007

    Directory of Open Access Journals (Sweden)

    Yun-Lin Lu

    2015-01-01

    Full Text Available Background: Injuries are the leading causes of death and contribute greatly to morbidity in children. Our study examined injuries′ age and gender-specific variations over time among children 0-19, from 1989 to 2007. Materials and Methods: Numbers of deaths caused by injury are drawn from Taiwan′s official Vital Statistics System. Mortality was age-adjusted to the US 2000 standard population. Temporal trends were analyzed by linear regression. Results: Both genders′ annual mortality rates and proportional mortality ratios of unintentional injuries declined significantly during 1989-2007. Conversely, an increasing trend of intentional deaths occurred. In general, during 1992-2007, increasing the rates of suicide deaths in ages 10-19 and of homicide deaths in ages 0-9 occurred. Boys had more suicide deaths than did girls. Conclusions: Unlike unintentional injuries, intentional injuries increased over the 1989-2007 period. Deaths in the subgroups of ages 0-19 and categorized by genders were caused by varying injuries.

  15. Long-term trends in the St. Marys River open water fish community

    Science.gov (United States)

    Schaeffer, Jeffrey S.; Fielder, David G.; Godby, Neal; Bowen, Anjanette; O'Connor, Lisa; Parrish, Josh; Greenwood, Susan; Chong, Stephen; Wright, Greg

    2011-01-01

    We examined trends in species composition and abundance of the St. Marys River fish community. Abundance data were available approximately once every six years from 1975 through 2006, and size and age data were available from 1995 through 2006. We also compared survey data in 2006 with results of a concurrent creel survey that year, as well as data from prior surveys spanning a 69 year time frame. The St. Marys River fish community was best characterized as a coolwater fish community with apparent little variation in species composition, and only slight variation in overall fish abundance since 1975. However, we did find recent trends in abundance among target species sought by anglers: centrarchids increased, percids appeared stable, and both northern pike Esox lucius and cisco Coregonus artedii declined. Survey results suggested that walleye (Sander vitreus) and yellow perch (Perca flavescens) experienced moderate exploitation but benefited from recent strong recruitment and faster growth. Mechanisms underlying declines of northern pike and cisco were not clear; reduced abundance could have resulted from high exploitation, variation in recruitment, or a combination of both factors. Despite these challenges, the St. Marys River fish community appears remarkably stable. We suggest that managers insure that creel surveys occur simultaneously with assessments, but periodic gill net surveys may no longer provide adequate data in support of recent, more complex management objectives. While additional surveys would add costs, more frequent data might ensure sustainability of a unique fish community that supports a large proportion of angler effort on Lake Huron.

  16. Effect of long-term organic fertilization on the soil pore characteristics of greenhouse vegetable fields converted from rice-wheat rotation fields.

    Science.gov (United States)

    Xu, L Y; Wang, M Y; Shi, X Z; Yu, Q B; Shi, Y J; Xu, S X; Sun, W X

    2018-08-01

    The shift from rice-wheat rotation (RWR) to greenhouse vegetable soils has been widely practiced in China. Several studies have discussed the changes in soil properties with land-use changes, but few studies have sought to address the differences in soil pore properties, especially for fields based on long-term organic fertilization under greenhouse vegetable system from RWR fields. This study uses the X-ray computed tomography (CT) scanning and statistical analysis to compare the long-term effects of the conversion of organic greenhouse vegetable fields (over one year, nine years, and fourteen years) from RWR fields on the soil macropore structure as well as the influencing factors from samples obtained in Nanjing, Jiangsu, China, using the surface soil layer and triplicate samples. The results demonstrated that the macropore structure became more complex and stable, with a higher connectivity, fractal dimension (FD) and a lower degree of anisotropy (DA), as the greenhouse vegetable planting time increased. The total topsoil macroporosity increased considerably, but the rate of increase gradually decelerated with time. The transmission pores (round pores ranging from 50 to 500μm) increased with time, but the biopores (>2000μm) clearly decreased after nine years of use as greenhouse vegetable fields. Soil organic matter (OM) has a significant relationship with the soil pore structure characteristics, especially for the transmission pores. In addition, organic fertilization on the topsoil had a short-term effect on the pores, but the effect stabilized and had a weak influence on the pores over longer periods. These results suggested that organic fertilization was conducive for controlling soil degradation regarding it physical quality for water and oxygen availability in the short term. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Long-term meteorologically independent trend analysis of ozone air quality at an urban site in the greater Houston area.

    Science.gov (United States)

    Botlaguduru, Venkata S V; Kommalapati, Raghava R; Huque, Ziaul

    2018-04-19

    The Houston-Galveston-Brazoria (HGB) area of Texas has a history of ozone exceedances and is currently classified under moderate nonattainment status for the 2008 8-hr ozone standard of 75 ppb. The HGB area is characterized by intense solar radiation, high temperature, and humidity, which influence day-to-day variations in ozone concentrations. Long-term air quality trends independent of meteorological influence need to be constructed for ascertaining the effectiveness of air quality management in this area. The Kolmogorov-Zurbenko (KZ) filter technique used to separate different scales of motion in a time series, is applied in the current study for maximum daily 8-hr (MDA8) ozone concentrations at an urban site (EPA AQS Site ID: 48-201-0024, Aldine) in the HGB area. This site located within 10 miles of downtown Houston and the George Bush Intercontinental Airport, was selected for developing long-term meteorologically independent MDA8 ozone trends for the years 1990-2016. Results from this study indicate a consistent decrease in meteorologically independent MDA8 ozone between 2000-2016. This pattern could be partially attributed to a reduction in underlying NO X emissions, particularly that of lowering nitrogen dioxide (NO 2 ) levels, and a decrease in the release of highly reactive volatile organic compounds (HRVOC). Results also suggest solar radiation to be most strongly correlated to ozone, with temperature being the secondary meteorological control variable. Relative humidity and wind speed have tertiary influence at this site. This study observed that meteorological variability accounts for a high of 61% variability in baseline ozone (low-frequency component, sum of long-term and seasonal components), while 64% of the change in long-term MDA8 ozone post-2000 could be attributed to NO X emissions reduction. Long-term MDA8 ozone trend component was estimated to be decreasing at a linear rate of 0.412 ± 0.007 ppb/yr for the years 2000-2016, and 0.155

  18. Public Awareness of Uterine Power Morcellation Through US Food and Drug Administration Communications: Analysis of Google Trends Search Term Patterns.

    Science.gov (United States)

    Wood, Lauren N; Jamnagerwalla, Juzar; Markowitz, Melissa A; Thum, D Joseph; McCarty, Philip; Medendorp, Andrew R; Raz, Shlomo; Kim, Ja-Hong

    2018-04-26

    Uterine power morcellation, where the uterus is shred into smaller pieces, is a widely used technique for removal of uterine specimens in patients undergoing minimally invasive abdominal hysterectomy or myomectomy. Complications related to power morcellation of uterine specimens led to US Food and Drug Administration (FDA) communications in 2014 ultimately recommending against the use of power morcellation for women undergoing minimally invasive hysterectomy. Subsequently, practitioners drastically decreased the use of morcellation. We aimed to determine the effect of increased patient awareness on the decrease in use of the morcellator. Google Trends is a public tool that provides data on temporal patterns of search terms, and we correlated this data with the timing of the FDA communication. Weekly relative search volume (RSV) was obtained from Google Trends using the term “morcellation.” Higher RSV corresponds to increases in weekly search volume. Search volumes were divided into 3 groups: the 2 years prior to the FDA communication, a 1-year period following, and thereafter, with the distribution of the weekly RSV over the 3 periods tested using 1-way analysis of variance. Additionally, we analyzed the total number of websites containing the term “morcellation” over this time. The mean RSV prior to the FDA communication was 12.0 (SD 15.8), with the RSV being 60.3 (SD 24.7) in the 1-year after and 19.3 (SD 5.2) thereafter (PGoogle search activity about morcellation of uterine specimens increased significantly after the FDA communications. This trend indicates an increased public awareness regarding morcellation and its complications. More extensive preoperative counseling and alteration of surgical technique and clinician practice may be necessary. ©Lauren N Wood, Juzar Jamnagerwalla, Melissa A Markowitz, D Joseph Thum, Philip McCarty, Andrew R Medendorp, Shlomo Raz, Ja-Hong Kim. Originally published in JMIR Public Health and Surveillance (http

  19. Fire and vegetation history on Santa Rosa Island, Channel Islands, and long-term environmental change in southern California

    Science.gov (United States)

    Starratt, Scott W.; Pinter, N.; Anderson, Robert S.; Jass, R.B.

    2009-01-01

    The long-term history of vegetation and fire was investigated at two locations – Soledad Pond (275 m; from ca. 12 000 cal. a BP) and Abalone Rocks Marsh (0 m; from ca. 7000 cal. a BP) – on Santa Rosa Island, situated off the coast of southern California. A coastal conifer forest covered highlands of Santa Rosa during the last glacial, but by ca. 11 800 cal. a BP Pinus stands, coastal sage scrub and grassland replaced the forest as the climate warmed. The early Holocene became increasingly drier, particularly after ca. 9150 cal. a BP, as the pond dried frequently, and coastal sage scrub covered the nearby hillslopes. By ca. 6900 cal. a BP grasslands recovered at both sites. Pollen of wetland plants became prominent at Soledad Pond after ca. 4500 cal. a BP, and at Abalone Rocks Marsh after ca. 3465 cal. a BP. Diatoms suggest freshening of the Abalone Rocks Marsh somewhat later, probably by additional runoff from the highlands. Introduction of non-native species by ranchers occurred subsequent to AD 1850. Charcoal influx is high early in the record, but declines during the early Holocene when minimal biomass suggests extended drought. A general increase occurs after ca. 7000 cal. a BP, and especially after ca. 4500 cal. a BP. The Holocene pattern closely resembles population levels constructed from the archaeological record, and suggests a potential influence by humans on the fire regime of the islands, particularly during the late Holocene.

  20. The Australian Dollar's Long-Term Fluctuations and Trend: The Commodity Prices-cum-Economic Cycles Hypothesis

    OpenAIRE

    Sanidas, Elias

    2005-01-01

    The Australian dollar’s exchange rate (mainly in relation to the American dollar) has received a considerable attention in research and several models have been proposed to explain its trend and fluctuations. Thus, as a conclusion of this research we can say that this commodity currency very much depends on the terms of trade which in turn depend on commodity prices. The present paper is based on this conclusion and hence proposes the possibility that the Australian dollar’s behavior is overw...

  1. Identification of sources and long term trends for pollutants in the arctic using isentropic trajectory analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mahura, A.; Jaffe, D.; Harris, J.

    2003-07-01

    The understanding of factors driving climate and ecosystem changes in the Arctic requires careful consideration of the sources, correlation and trends for anthropogenic pollutants. The database from the NOAA-CMDL Barrow Observatory (71deg.17'N, 156deg.47'W) is the longest and most complete record of pollutant measurements in the Arctic. It includes observations of carbon dioxide (CO{sub 2}), methane (CH{sub 4}), carbon monoxide (CO), ozone (O{sub 3}), aerosol scattering coefficient ({sigma}{sub sp}), aerosol number concentration (NC{sub asl}), etc. The objectives of this study are to understand the role of long-range transport to Barrow in explaining: (1) the year-to-year variations, and (2) the trends in the atmospheric chemistry record at the NOAA-CMDL Barrow observatory. The key questions we try to answer are: 1. What is the relationship between various chemical species measured at Barrow Observatory, Alaska and transport pathways at various altitudes? 2. What are the trends of species and their relation to transport patterns from the source regions? 3. What is the impact of the Prudhoe Bay emissions on the Barrow's records? To answer on these questions we apply the following main research tools. First, it is an isentropic trajectory model used to calculate the trajectories arriving at Barrow at three altitudes of 0.5, 1.5 and 3 km above sea level. Second - clustering procedure used to divide the trajectories into groups based on source regions. Third - various statistical analysis tools such as the exploratory data analysis, two component correlation analysis, trend analysis, principal components and factor analysis used to identify the relationship between various chemical species vs. source regions as a function of time. In this study, we used the chemical data from the NOAA-CMDL Barrow observatory in combination with isentropic backward trajectories from gridded ECMWF data to understand the importance of various pollutant source regions on

  2. Identification of sources and long term trends for pollutants in the arctic using isentropic trajectory analysis

    International Nuclear Information System (INIS)

    Mahura, A.; Jaffe, D.; Harris, J.

    2003-01-01

    The understanding of factors driving climate and ecosystem changes in the Arctic requires careful consideration of the sources, correlation and trends for anthropogenic pollutants. The database from the NOAA-CMDL Barrow Observatory (71deg.17'N, 156deg.47'W) is the longest and most complete record of pollutant measurements in the Arctic. It includes observations of carbon dioxide (CO 2 ), methane (CH 4 ), carbon monoxide (CO), ozone (O 3 ), aerosol scattering coefficient (σ sp ), aerosol number concentration (NC asl ), etc. The objectives of this study are to understand the role of long-range transport to Barrow in explaining: (1) the year-to-year variations, and (2) the trends in the atmospheric chemistry record at the NOAA-CMDL Barrow observatory. The key questions we try to answer are: 1. What is the relationship between various chemical species measured at Barrow Observatory, Alaska and transport pathways at various altitudes? 2. What are the trends of species and their relation to transport patterns from the source regions? 3. What is the impact of the Prudhoe Bay emissions on the Barrow's records? To answer on these questions we apply the following main research tools. First, it is an isentropic trajectory model used to calculate the trajectories arriving at Barrow at three altitudes of 0.5, 1.5 and 3 km above sea level. Second - clustering procedure used to divide the trajectories into groups based on source regions. Third - various statistical analysis tools such as the exploratory data analysis, two component correlation analysis, trend analysis, principal components and factor analysis used to identify the relationship between various chemical species vs. source regions as a function of time. In this study, we used the chemical data from the NOAA-CMDL Barrow observatory in combination with isentropic backward trajectories from gridded ECMWF data to understand the importance of various pollutant source regions on atmospheric composition in the Arctic. We

  3. Statistical modelling and RCS detrending methods provide similar estimates of long-term trend in radial growth of common beech in north-eastern France

    OpenAIRE

    Bontemps , Jean-Daniel; Esper , Jan

    2011-01-01

    International audience; Dendrochronological methods have greatly contributed to the documentation of past long-term trends in forest growth. These methods primarily focus on the high-frequency signals of tree ring chronologies. They require the removal of the ageing trend in tree growth, known as 'standardisation' or 'detrending', as a prerequisite to the estimation of such trends. Because the approach is sequential, it may however absorb part of the low-frequency historical signal. In this s...

  4. Comparative long-term trend analysis of daily weather conditions with daily pollen concentrations in Brussels, Belgium

    Science.gov (United States)

    Bruffaerts, Nicolas; De Smedt, Tom; Delcloo, Andy; Simons, Koen; Hoebeke, Lucie; Verstraeten, Caroline; Van Nieuwenhuyse, An; Packeu, Ann; Hendrickx, Marijke

    2018-03-01

    A clear rise in seasonal and annual temperatures, a gradual increase of total radiation, and a relative trend of change in seasonal precipitation have been observed for the last four decades in Brussels (Belgium). These local modifications may have a direct and indirect public health impact by altering the timing and intensity of allergenic pollen seasons. In this study, we assessed the statistical correlations (Spearman's test) between pollen concentration and meteorological conditions by using long-term daily datasets of 11 pollen types (8 trees and 3 herbaceous plants) and 10 meteorological parameters observed in Brussels between 1982 and 2015. Furthermore, we analyzed the rate of change in the annual cycle of the same selected pollen types by the Mann-Kendall test. We revealed an overall trend of increase in daily airborne tree pollen (except for the European beech tree) and an overall trend of decrease in daily airborne pollen from herbaceous plants (except for Urticaceae). These results revealed an earlier onset of the flowering period for birch, oak, ash, plane, grasses, and Urticaceae. Finally, the rates of change in pollen annual cycles were shown to be associated with the rates of change in the annual cycles of several meteorological parameters such as temperature, radiation, humidity, and rainfall.

  5. Comparative long-term trend analysis of daily weather conditions with daily pollen concentrations in Brussels, Belgium.

    Science.gov (United States)

    Bruffaerts, Nicolas; De Smedt, Tom; Delcloo, Andy; Simons, Koen; Hoebeke, Lucie; Verstraeten, Caroline; Van Nieuwenhuyse, An; Packeu, Ann; Hendrickx, Marijke

    2018-03-01

    A clear rise in seasonal and annual temperatures, a gradual increase of total radiation, and a relative trend of change in seasonal precipitation have been observed for the last four decades in Brussels (Belgium). These local modifications may have a direct and indirect public health impact by altering the timing and intensity of allergenic pollen seasons. In this study, we assessed the statistical correlations (Spearman's test) between pollen concentration and meteorological conditions by using long-term daily datasets of 11 pollen types (8 trees and 3 herbaceous plants) and 10 meteorological parameters observed in Brussels between 1982 and 2015. Furthermore, we analyzed the rate of change in the annual cycle of the same selected pollen types by the Mann-Kendall test. We revealed an overall trend of increase in daily airborne tree pollen (except for the European beech tree) and an overall trend of decrease in daily airborne pollen from herbaceous plants (except for Urticaceae). These results revealed an earlier onset of the flowering period for birch, oak, ash, plane, grasses, and Urticaceae. Finally, the rates of change in pollen annual cycles were shown to be associated with the rates of change in the annual cycles of several meteorological parameters such as temperature, radiation, humidity, and rainfall.

  6. Autonomous long-term gamma-spectrometric monitoring of submarine groundwater discharge trends in Hawaii

    International Nuclear Information System (INIS)

    Dulai, Henrietta; Waters, Ch.A.; Kennedy, Joseph; Kamenik, Jan; Academy of Sciences of the Czech Republic, Rez; Babinec, James; Jolly, James; Williamson, Mario

    2016-01-01

    We developed a fully autonomous underwater gamma-spectrometer for long-term coastal submarine groundwater discharge (SGD) monitoring. The instrument represents a significant improvement over previous submarine gamma-spectrometers in that it is very robust, has high sensitivity allowing high temporal resolution, and is completely autonomous. Here we describe the technical parameters of the new instrument as well as data collected over its 9-month deployment in Kiholo Bay, HI, USA. We also present methods to convert the measured activities to SGD rates. In Kiholo Bay, the derived SGD matched previous estimates but in addition it revealed previously undocumented short- and long-term patterns in SGD. (author)

  7. Long-term effects of submergence and wetland vegetation on metals in a 90-year old abandoned Pb-Zn mine tailings pond

    International Nuclear Information System (INIS)

    Jacob, Donna L.; Otte, Marinus L.

    2004-01-01

    A Pb-Zn tailings pond, abandoned for approximately 90 years, has been naturally colonized by Glyceria fluitans and is an excellent example of long-term metal retention in tailings ponds under various water cover and vegetation conditions. Shallow/intermittently flooded areas (dry zone) were unvegetated and low in organic matter (OM) content. Permanently flooded areas were either unvegetated with low OM, contained dead vegetation and high OM, or living plants and high OM. It was expected that either water cover or high OM would result in enhanced reducing conditions and lower metal mobility, but live plants would increase metal mobility due to root radial oxygen loss. The flooded low OM tailings showed higher As and Fe mobility compared with dry low OM tailings. In the permanently flooded areas without live vegetation, the high OM content decreased Zn mobility and caused extremely high concentrations of acid-volatile sulfides (AVS). In areas with high OM, living plants significantly increased Zn mobility and decreased concentrations of AVS, indicating root induced sediment oxidation or decreased sulfate-reduction. This is the first study reporting the ability of wetland plants to affect the metal mobility and AVS in long-term (decades), unmanaged tailings ponds. - Metal and acid-volatile sulfide concentrations were affected differently by flooding vegetation

  8. Photovoltaic (PV) Pricing Trends: Historical, Recent, and Near-Term Projections

    Energy Technology Data Exchange (ETDEWEB)

    Feldman, D.; Barbose, G.; Margolis, R.; Wiser, R.; Darghouth, N.; Goodrich, A.

    2012-11-01

    This report helps to clarify the confusion surrounding different estimates of system pricing by distinguishing between past, current, and near-term projected estimates. It also discusses the different methodologies and factors that impact the estimated price of a PV system, such as system size, location, technology, and reporting methods.These factors, including timing, can have a significant impact on system pricing.

  9. Long-Term United Kindrom Trends in the Breeding Phenology of the Common Frog, Rana temporaria

    Czech Academy of Sciences Publication Activity Database

    Scott, W.A.; Pithart, David; Adamson, J. K.

    2008-01-01

    Roč. 42, č. 1 (2008), s. 89-96 ISSN 0022-1511 Institutional research plan: CEZ:AV0Z60870520 Keywords : Long-term * Common Frog * Breeding * Rana temporaria Subject RIV: EG - Zoology Impact factor: 0.888, year: 2008

  10. Autonomous long-term gamma-spectrometric monitoring of submarine groundwater discharge trends in Hawaii

    Czech Academy of Sciences Publication Activity Database

    Dulai, H.; Kameník, Jan; Waters, C. A.; Kennedy, J.; Babinec, J.; Jolly, J.; Williamson, M.

    2016-01-01

    Roč. 307, č. 3 (2016), s. 1865-1870 ISSN 0236-5731. [10th International Conference on Methods and Applications of Radioanalytical Chemistry (MARC). Kailua Kona, 12.04.2015-17.04.2015] Institutional support: RVO:61389005 Keywords : submarine groundwater discharge * long-term SGD monitoring * underwater gammaspectrometry Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.282, year: 2016

  11. Long-term trends in nutrient budgets of the western Dutch Wadden Sea (1976–2012)

    NARCIS (Netherlands)

    Jung, A.S; Brinkman, A.G.; Folmer, E.O.; Herman, P.M.J.; van der Veer, H.W.; Philippart, C.J.M.

    2017-01-01

    Long-term field observations of nitrogen [N] and phosphorus [P] concentrations were used to construct nutrient budgets for the western Dutch Wadden Sea between 1976 and 2012. Nutrients come into the western Dutch Wadden Sea via river runoff, through exchange with the coastal zone of the North Sea,

  12. Long term trends in economic inequality : Lessons from colonial Botswana 1921–1974

    NARCIS (Netherlands)

    Bolt, Jutta; Hillbom, Ellen

    2016-01-01

    This article contributes to the growing literature on colonial legacies influencing long-term development. It focuses on Botswana, a case where the post-independence diamond-led economy has been considered an economic success story, despite its high levels of inequality. Here it is argued that this

  13. Long-term trends of phosphorus concentrations in an artificial lake: Socio-economic and climate drivers.

    Science.gov (United States)

    Vystavna, Yuliya; Hejzlar, Josef; Kopáček, Jiří

    2017-01-01

    European freshwater ecosystems have undergone significant human-induced and environmentally-driven variations in nutrient export from catchments throughout the past five decades, mainly in connection with changes in land-use, agricultural practice, waste water production and treatment, and climatic conditions. We analysed the relations among concentration of total phosphorus (TP) in the Slapy Reservoir (a middle reservoir of the Vltava River Cascade, Czechia), and socio-economic and climatic factors from 1963 to 2015. The study was based on a time series analysis, using conventional statistical tools, and the identification of breaking points, using a segmented regression. Results indicated clear long-term trends and seasonal patterns of TP, with annual average TP increasing up until 1991 and decreasing from 1992 to 2015. Trends in annual, winter and spring average TP concentrations reflected a shift in development of sewerage and sanitary infrastructure, agricultural application of fertilizers, and livestock production in the early 1990s that was associated with changes from the planned to the market economy. No trends were observed for average TP in autumn. The summer average TP has fluctuated with increased amplitude since 1991 in connection with recent climate warming, changes in thermal stratification stability, increased water flow irregularities, and short-circuiting of TP-rich inflow during high flow events. The climate-change-induced processes confound the generally declining trend in lake-water TP concentration and can result in eutrophication despite decreased phosphorus loads from the catchment. Our findings indicate the need of further reduction of phosphorus sources to meet ecological quality standards of the EU Water Framework Directive because the climate change may lead to a greater susceptibility of the aquatic ecosystem to the supply of nutrients.

  14. Trends of PM2.5 concentrations in China: A long term approach.

    Science.gov (United States)

    Fontes, Tânia; Li, Peilin; Barros, Nelson; Zhao, Pengjun

    2017-07-01

    The fast economic growth of China along the last two decades has created a strong impact on the environment. The occurrence of heavy haze pollution days is the most visible effect. Although many researchers have studied such problem, a high number of spatio-temporal limitations in the recent studies were identified. From our best knowledge the long trends of PM 2.5 concentrations were not fully investigated in China, in particular the year-to-year trends and the seasonal and daily cycles. Therefore, in this work the PM 2.5 concentrations collected from automatic monitors from five urban sites located in megacities with different climatic zones in China were analysed: Beijing (40°N), Chengdu (31°N), Guangzhou (23°N), Shanghai (31°N) and Shenyang (43°N). For an inter-comparison a meta-analysis was carried out. An evaluation conducted since 1999 demonstrates that PM 2.5 concentrations have been reduced until 2008, period which match with the occurrence of the Olympic Games. However, a seasonal analysis highlight that such decrease occurs mostly during warmer seasons than cold seasons. During winter PM 2.5 concentrations are typically 1.3 to 2.7 higher than in summer. The average daily cycle shows that the lowest and highest PM 2.5 concentrations often occurs in the afternoon and evening hours respectively. Such daily variations are mostly driven by the daily variation of the boundary layer depth and emissions. Although the PM 2.5 levels have showing signs of improvement, even during the warming season the values are still too high in comparison with the annual environmental standards of China (35 μg m -3 ). Moreover, during cold seasons the north regions have values twice higher than this limit. Thus, to fulfil these standards the governmental mitigation measures need to be strongly reinforced in order to optimize the daily living energy consumption, primarily in the north regions of China and during the winter periods. Copyright © 2017 Elsevier Ltd. All

  15. Long-term trends in radial growth of Siberian spruce and Scots pine in Komi Republic (northwestern Russia)

    Energy Technology Data Exchange (ETDEWEB)

    Lopatin, E. (Univ. of Joensuu (Finland)); Kolstroem, T. (Russian Academy of Sciences, Syktyvkar (Russian Federation)); Spiecker, H. (Univ. of Freiburg (Germany))

    2008-07-01

    Komi is situated on the eastern boundary of the European part of Russia, in the boreal region where large areas of natural forest still exist. Using radial growth measurements it was possible to attain positive long-term trends of growth in Scots pine (Pinus sylvestris) and Siberian spruce (Picea obovata) in the Komi Republic. Increases in the radial growth of Siberian spruce in the forest-tundra were 134% and in the northern taiga zone 35% over successive 50-year periods from 1901 to 1950 and from 1951 to 2000. Respectively, in the middle taiga zone a 76% increase in radial growth was found (over 100 years), whilst in the southern taiga zone the changes were not statistically significant. The increase in radial growth of Scots pine in the northern taiga zone was 32%. In the middle taiga zone the radial growth increase in Scots pine was 55% and in the southern taiga zone the changes were not statistically significant. The long-term growth trends of Komi were compared with those in other parts of Europe. (orig.)

  16. Increasing Juniperus virginiana L. pollen in the Tulsa atmosphere: long-term trends, variability, and influence of meteorological conditions

    Science.gov (United States)

    Flonard, Michaela; Lo, Esther; Levetin, Estelle

    2018-02-01

    In the Tulsa area, the Cupressaceae is largely represented by eastern red cedar ( Juniperus virginiana L.). The encroachment of this species into the grasslands of Oklahoma has been well documented, and it is believed this trend will continue. The pollen is known to be allergenic and is a major component of the Tulsa atmosphere in February and March. This study examined airborne Cupressaceae pollen data from 1987 to 2016 to determine long-term trends, pollen seasonal variability, and influence of meteorological variables on airborne pollen concentrations. Pollen was collected through means of a Burkard sampler and analyzed with microscopy. Daily pollen concentrations and yearly pollen metrics showed a high degree of variability. In addition, there were significant increases over time in the seasonal pollen index and in peak concentrations. These increases parallel the increasing population of J. virginiana in the region. Pollen data were split into pre- and post-peak categories for statistical analyses, which revealed significant differences in correlations of the two datasets when analyzed with meteorological conditions. While temperature and dew point, among others were significant in both datasets, other factors, like relative humidity, were significant only in one dataset. Analyses using wind direction showed that southerly and southwestern winds contributed to increased pollen concentrations. This study confirms that J. virginiana pollen has become an increasing risk for individuals sensitive to this pollen and emphasizes the need for long-term aerobiological monitoring in other areas.

  17. Long-Term Climate Trends and Extreme Events in Northern Fennoscandia (1914–2013

    Directory of Open Access Journals (Sweden)

    Sonja Kivinen

    2017-02-01

    Full Text Available We studied climate trends and the occurrence of rare and extreme temperature and precipitation events in northern Fennoscandia in 1914–2013. Weather data were derived from nine observation stations located in Finland, Norway, Sweden and Russia. The results showed that spring and autumn temperatures and to a lesser extent summer temperatures increased significantly in the study region, the observed changes being the greatest for daily minimum temperatures. The number of frost days declined both in spring and autumn. Rarely cold winter, spring, summer and autumn seasons had a low occurrence and rarely warm spring and autumn seasons a high occurrence during the last 20-year interval (1994–2013, compared to the other 20-year intervals. That period was also characterized by a low number of days with extremely low temperature in all seasons (4–9% of all extremely cold days and a high number of April and October days with extremely high temperature (36–42% of all extremely warm days. A tendency of exceptionally high daily precipitation sums to grow even higher towards the end of the study period was also observed. To summarize, the results indicate a shortening of the cold season in northern Fennoscandia. Furthermore, the results suggest significant declines in extremely cold climate events in all seasons and increases in extremely warm climate events particularly in spring and autumn seasons.

  18. Long-term trends in the uptake of radiocesium in Rozites caperatus

    DEFF Research Database (Denmark)

    Strandberg, M.

    2004-01-01

    Measurements of Cs-134 and Cs-137 in Rozites caperatus from 1991 to 2001 showed differences in the uptake pattern of Chernobyl and fallout derived radiocesium over time. The effective half-life of Chernobyl derived Cs-137 was determined to 12.4 years, whereas fallout derived Cs-137 had an effective...... half-life of 9.8 years. However, the trend for Chernobyl derived Cs-137 was clearly not linear. An effective average half-life of 3.1 years was determined for Chernobyl derived Cs-137 in the period from 1991 to 1994. The corresponding ecological half-life was 3.4 years. In the period from 1994 to 2001...... it is possible that the effective half-life was longer than the physical, which indicates that more Chernobyl cesium becomes available than disappears through radioactive decay. The difference may be due to depth distribution of radiocesium, i.e. fallout derived cesium have penetrated deeper than Chernobyl...

  19. Long-term trends in direct and indirect household energy intensities: a factor in dematerialisation?

    International Nuclear Information System (INIS)

    Vringer, K.; Blok, K.

    2000-01-01

    Dematerialisation is assumed to contribute significantly to the alleviation of environmental problems. One of the possible causes of dematerialisation is a change in the consumption patterns of households. The aim of this article is to analyse changes in consumption patterns of Dutch households in the period between 1948 to 1996 in order to discover whether these changes have influenced the energy intensity of society. Due to the rise in consumption, the total household energy requirement per capita grew on average by 2.4 per cent per year over a period of 48 years (this figure ignores efficiency changes in the supplying sectors). In the same period the total energy intensity of households fluctuated but on average changed from 5.6 to 6.3 MJ/NLG, an increase of 0.25 per cent per year. If we exclude the direct energy consumption we find a slight decline in the indirect energy intensity, namely from 3.8 to 3.6 MJ/NLG ( - 0.14 per cent per year). No significant trends to a lower energy intensity are found and there is no indication of dematerialisation of the consumption patterns. If governments pursue a policy of sustainable development they have to take into account the fact that dematerialisation of the consumption pattern does not seem to be an autonomous process. (author)

  20. Emergency medical readmission: long-term trends and impact on mortality.

    LENUS (Irish Health Repository)

    Glynn, Nigel

    2011-04-01

    There is increasing emphasis on prevention of emergency medical readmissions. The broad pattern of acute medical readmissions was studied over a seven-year period and the impact of any readmission on 30-day mortality was recorded. Significant predictors of outcome, including co-morbidity and illness severity score, were entered into a multivariate regression model, adjusting the univariate estimates of the readmission status on mortality. In total, 23,114 consecutive acute medical patients were admitted between 2002-8; the overall readmission rate was 27%. Readmission independently predicted an increased 30-day mortality; the odds ratio, was 1.12 (95% confidence interval (CI) 1.09 to 1.14). This fell to 1.05 (95% CI 1.02 to 1.08) when adjusted for outcome predictors including acute illness severity. The trend for readmissions was to progressively increase over time; the median times between consecutive admissions formed an exponential time series. Efforts to reduce or avoid readmissions may depend on an ability to modify the underlying chronic disease.

  1. Investigation of short and long term trends in chemical composition of Eastern Mediterranean aerosols

    International Nuclear Information System (INIS)

    2011-01-01

    A collaborative study was started with the Middle East Technical University, Environmental Engineering Department in 2004 in order to determine the transport of air pollutants and their deposition rates to Eastern Mediterranean with the ultimate aim of filling the gaps in knowledge on the current status of Eastern Mediterranean air quality profile. Collection sufficient amount of representative samples, analyzes of the collected samples with high accuracy and precision and interpretation of generated data are crucial efforts. To attain this goal, EDXRF spectrometer, which is a rapid, reliable and sensitive analytical instrument, located at our center was employed in analysis of the collected samples after calibration with 'NIST 2783 Air Particles on Filter'. The effectiveness of the control strategies taken on the emissions was discussed by investigating the short and long term variations in the chemical composition of samples collected between 1993 and 2001 at Antalya station. In this context, generated data set was studied for short (daily) term, seasonal and long term variations. It has been found that short term variations in the concentrations of pollutants in short time scale are highly episodic. The concentration of measured pollutants was changed 10-20 folds in the subsequent two days. The most important factors affecting the chemical composition of pollutants in short time interval are meteorological factors such as precipitation and variations observed at the emission strength of pollutants. The declined in Pb concentrations at the Antalya station was attributed to observed decrease in Pb emissions in Europe after the introduction of leaded gasoline. Highest summer averages were reported for anthropogenic pollutants in summer months. Aegean Sea (Izmir-Aliaga) studies of the project will be completed this year

  2. Long-term Trends of Organic Carbon Concentrations in Freshwaters: Strengths and Weaknesses of Existing Evidence

    Directory of Open Access Journals (Sweden)

    Montserrat Filella

    2014-05-01

    Full Text Available Many articles published in the last few years start with the assumption that the past decades have seen an increase in dissolved organic carbon (DOC concentrations in the rivers and lakes of the Northern Hemisphere. This study analyses whether the existing evidence supports this claim. With this aim, we have collected published studies where long series of organic carbon concentrations (i.e., longer than 10 years were analyzed for existing trends and have carefully evaluated the 63 articles found. Information has been collated in a comprehensive and comparable way, allowing readers to easily access it. The two main aspects considered in our analysis have been the analytical methods used and the data treatment methods applied. Both are sensitive issues because, on the one hand, the difficulties associated with correctly determining organic carbon concentrations in surface waters are well known, while, on the other, dealing with real environmental data (i.e., lack of normality, censoring, missing values, etc. is an extremely intricate matter. Other issues such as data reporting and the geographical location of the systems studied are also discussed. In conclusion, it is clear that organic carbon concentrations have increased in some surface waters in the Northern Hemisphere since the 1990s. However, due to a lack of data in many parts of the world, it is not known whether this phenomenon is general and, more importantly, in the areas for which such data do exist, the reporting and methodological problems in the published studies prevent any conclusion on the existence of a general temporal behavior of organic carbon from being drawn.

  3. Sampling design for long-term regional trends in marine rocky intertidal communities

    Science.gov (United States)

    Irvine, Gail V.; Shelley, Alice

    2013-01-01

    Probability-based designs reduce bias and allow inference of results to the pool of sites from which they were chosen. We developed and tested probability-based designs for monitoring marine rocky intertidal assemblages at Glacier Bay National Park and Preserve (GLBA), Alaska. A multilevel design was used that varied in scale and inference. The levels included aerial surveys, extensive sampling of 25 sites, and more intensive sampling of 6 sites. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope ≤30° was rare. This unexpected finding illustrated one value of probability-based surveys and led to a shift in the target habitat type to include steeper, more mixed rocky habitat. Subsequently, we evaluated the statistical power of different sampling methods and sampling strategies to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles Balanomorpha, the mussel Mytilus trossulus, and the rockweed Fucus distichus subsp. evanescens. There was greatest power to detect trends in Mytilus and lesser power for barnacles and Fucus. Because of its greater power, the extensive, coarse-grained sampling scheme was adopted in subsequent years over the intensive, fine-grained scheme. The sampling attributes that had the largest effects on power included sampling of “vertical” line transects (vs. horizontal line transects or quadrats) and increasing the number of sites. We also evaluated the power of several management-set parameters. Given equal sampling effort, sampling more sites fewer times had greater power. The information gained through intertidal monitoring is likely to be useful in assessing changes due to climate, including ocean acidification; invasive species; trampling effects; and oil spills.

  4. Short-Term Dynamic and Local Epidemiological Trends in the South American HIV-1B Epidemic.

    Directory of Open Access Journals (Sweden)

    Dennis Maletich Junqueira

    Full Text Available The human displacement and sexual behavior are the main factors driving the HIV-1 pandemic to the current profile. The intrinsic structure of the HIV transmission among different individuals has valuable importance for the understanding of the epidemic and for the public health response. The aim of this study was to characterize the HIV-1 subtype B (HIV-1B epidemic in South America through the identification of transmission links and infer trends about geographical patterns and median time of transmission between individuals. Sequences of the protease and reverse transcriptase coding regions from 4,810 individuals were selected from GenBank. Maximum likelihood phylogenies were inferred and submitted to ClusterPicker to identify transmission links. Bayesian analyses were applied only for clusters including ≥5 dated samples in order to estimate the median maximum inter-transmission interval. This study analyzed sequences sampled from 12 South American countries, from individuals of different exposure categories, under different antiretroviral profiles, and from a wide period of time (1989-2013. Continentally, Brazil, Argentina and Venezuela were revealed important sites for the spread of HIV-1B among countries inside South America. Of note, from all the clusters identified about 70% of the HIV-1B infections are primarily occurring among individuals living in the same geographic region. In addition, these transmissions seem to occur early after the infection of an individual, taking in average 2.39 years (95% CI 1.48-3.30 to succeed. Homosexual/Bisexual individuals transmit the virus as quickly as almost half time of that estimated for the general population sampled here. Public health services can be broadly benefitted from this kind of information whether to focus on specific programs of response to the epidemic whether as guiding of prevention campaigns to specific risk groups.

  5. Short-Term Dynamic and Local Epidemiological Trends in the South American HIV-1B Epidemic.

    Science.gov (United States)

    Junqueira, Dennis Maletich; de Medeiros, Rubia Marília; Gräf, Tiago; Almeida, Sabrina Esteves de Matos

    2016-01-01

    The human displacement and sexual behavior are the main factors driving the HIV-1 pandemic to the current profile. The intrinsic structure of the HIV transmission among different individuals has valuable importance for the understanding of the epidemic and for the public health response. The aim of this study was to characterize the HIV-1 subtype B (HIV-1B) epidemic in South America through the identification of transmission links and infer trends about geographical patterns and median time of transmission between individuals. Sequences of the protease and reverse transcriptase coding regions from 4,810 individuals were selected from GenBank. Maximum likelihood phylogenies were inferred and submitted to ClusterPicker to identify transmission links. Bayesian analyses were applied only for clusters including ≥5 dated samples in order to estimate the median maximum inter-transmission interval. This study analyzed sequences sampled from 12 South American countries, from individuals of different exposure categories, under different antiretroviral profiles, and from a wide period of time (1989-2013). Continentally, Brazil, Argentina and Venezuela were revealed important sites for the spread of HIV-1B among countries inside South America. Of note, from all the clusters identified about 70% of the HIV-1B infections are primarily occurring among individuals living in the same geographic region. In addition, these transmissions seem to occur early after the infection of an individual, taking in average 2.39 years (95% CI 1.48-3.30) to succeed. Homosexual/Bisexual individuals transmit the virus as quickly as almost half time of that estimated for the general population sampled here. Public health services can be broadly benefitted from this kind of information whether to focus on specific programs of response to the epidemic whether as guiding of prevention campaigns to specific risk groups.

  6. Unravelling long-term vegetation change patterns in a binational watershed using multitemporal land cover data and historical photography

    Science.gov (United States)

    Villarreal, Miguel L.; Norman, Laura M.; Webb, Robert H.; Boyer, Diane E.; Turner, Raymond M.

    2011-01-01

    A significant amount of research conducted in the Sonoran Desert of North America has documented, both anecdotally and empirically, major vegetation changes over the past century due to human land use activities. However, many studies lack coincidental landscape-scale data characterizing the spatial and temporal manifestation of these changes. Vegetation changes in a binational (USA and Mexico) watershed were documented using a series of four land cover maps (1979-2009) derived from multispectral satellite imagery. Cover changes are compared to georeferenced, repeat oblique photographs dating from the late 19th century to present. Results indicate the expansion of grassland over the past 20 years following nearly a century of decline. Historical repeat photography documents early-mid 20th century mesquite invasions, but recent land cover data and rephotography demonstrate declines in xeroriparian/riparian mesquite communities in recent decades. These vegetation changes are variable over the landscape and influenced by topography and land management.

  7. Long-term trends in sunshine duration and its association with schizophrenia birth rates and age at first registration--data from Australia and the Netherlands.

    Science.gov (United States)

    McGrath, John; Selten, Jean-Paul; Chant, David

    2002-04-01

    Based on the well-described excess of schizophrenia births in winter and spring, we hypothesised that individuals with schizophrenia (a) would be more likely to be born during periods of decreased perinatal sunshine, and (b) those born during periods of less sunshine would have an earlier age of first registration. We undertook an ecological analysis of long-term trends in perinatal sunshine duration and schizophrenia birth rates based on two mental health registers (Queensland, Australia n=6630; The Netherlands n=24,474). For each of the 480 months between 1931 and 1970, the agreement between slopes of the trends in psychosis and long-term sunshine duration series were assessed. Age at first registration was assessed by quartiles of long-term trends in perinatal sunshine duration. Males and females were assessed separately. Both the Dutch and Australian data showed a statistically significant association between falling long-term trends in sunshine duration around the time of birth and rising schizophrenia birth rates for males only. In both the Dutch and Australian data there were significant associations between earlier age of first registration and reduced long-term trends in sunshine duration around the time of birth for both males and females. A measure of long-term trends in perinatal sunshine duration was associated with two epidemiological features of schizophrenia in two separate data sets. Exposures related to sunshine duration warrant further consideration in schizophrenia research.

  8. The price of crude oil between 1973 et 2014: a cyclical trend over the long term

    International Nuclear Information System (INIS)

    Bui Xuan Hoi

    2015-01-01

    In 2014, given the geopolitical events occurring in regions that are highly sensitive for oil markets - Iraq, Iran, Syria, Russia, the Ukraine, etc. -, one could have expected a hike in the price of a barrel of crude oil. In fact, the opposite happened. Does this mean the end of a cycle characterised by high prices and the beginning of a new cycle epitomised by low prices on the international market place? What is really the mechanism behind long term price formation? Some of the answers emanate from the analysis of the 1973-2014 period. (author)

  9. Long-term temporal and spatial trends in eutrophication status of the Baltic Sea

    DEFF Research Database (Denmark)

    Andersen, Jesper; Carstensen, Jacob; Conley, Daniel J.

    2017-01-01

    the last 50–100 years. Secondly, the Baltic Sea is naturally susceptible to nutrient enrichment due to a combination of long retention times and stratification restricting ventilation of deep waters. Here, based on a unique data set collated from research activities and long-term monitoring programs, we......Much of the Baltic Sea is currently classified as ‘affected by eutrophication’. The causes for this are twofold. First, current levels of nutrient inputs (nitrogen and phosphorus) from human activities exceed the natural processing capacity with an accumulation of nutrients in the Baltic Sea over...

  10. LONG-TERM TREND OF SOLAR CORONAL HOLE DISTRIBUTION FROM 1975 TO 2014

    Energy Technology Data Exchange (ETDEWEB)

    Fujiki, K.; Tokumaru, M.; Hayashi, K.; Satonaka, D. [Institute for Space-Earth Environmental Research (ISEE), Nagoya University, Furo-cho, Chikusa, Nagoya Aichi 464-8601 (Japan); Hakamada, K., E-mail: fujiki@isee.nagoya-u.ac.jp [Department of Natural Science and Mathematics, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501 (Japan)

    2016-08-20

    We developed an automated prediction technique for coronal holes using potential magnetic field extrapolation in the solar corona to construct a database of coronal holes appearing from 1975 February to 2015 July (Carrington rotations from 1625 to 2165). Coronal holes are labeled with the location, size, and average magnetic field of each coronal hole on the photosphere and source surface. As a result, we identified 3335 coronal holes and found that the long-term distribution of coronal holes shows a similar pattern known as the magnetic butterfly diagram, and polar/low-latitude coronal holes tend to decrease/increase in the last solar minimum relative to the previous two minima.

  11. The long-term legacy of geomorphic and riparian vegetation feedbacks on the dammed Bill Williams River, Arizona, USA

    Science.gov (United States)

    Kui, Li; Stella, John C.; Shafroth, Patrick B.; House, P. Kyle; Wilcox, Andrew C.

    2017-01-01

    On alluvial rivers, fluvial landforms and riparian vegetation communities codevelop as a result of feedbacks between plants and abiotic processes. The influence of vegetation on river channel and floodplain geomorphology can be particularly strong on dammed rivers with altered hydrology and reduced flood disturbance. We used a 56-year series of aerial photos on the dammed Bill Williams River (Arizona, USA) to investigate how (a) different woody riparian vegetation types influence river channel planform and (b) how different fluvial landforms drive the composition of riparian plant communities over time. We mapped vegetation types and geomorphic surfaces and quantified how relations between fluvial and biotic processes covaried over time using linear mixed models. In the decades after the dam was built, woody plant cover within the river's bottomland nearly doubled, narrowing the active channel by 60% and transforming its planform from wide and braided to a single thread and more sinuous channel. Compared with native cottonwood–willow vegetation, nonnative tamarisk locally induced a twofold greater reduction in channel braiding. Vegetation expanded at different rates depending on the type of landform, with tamarisk cover on former high-flow channels increasing 17% faster than cottonwood–willow. Former low-flow channels with frequent inundation supported a greater increase in cottonwood–willow relative to tamarisk. These findings give insight into how feedbacks between abiotic and biotic processes in river channels accelerate and fortify changes triggered by dam construction, creating river systems increasingly distinct from predam ecological communities and landforms, and progressively more resistant to restoration of predam forms and processes.

  12. Multistate Models Reveal Long-Term Trends of Northern Spotted Owls in the Absence of a Novel Competitor.

    Directory of Open Access Journals (Sweden)

    Andrew J Kroll

    Full Text Available Quantifying spatial and temporal variability in population trends is a critical aspect of successful management of imperiled species. We evaluated territory occupancy dynamics of northern spotted owls (Strix occidentalis caurina, California, USA, 1990-2014. The study area possessed two unique aspects. First, timber management has occurred for over 100 years, resulting in dramatically different forest successional and structural conditions compared to other areas. Second, the barred owl (Strix varia, an exotic congener known to exert significant negative effects on spotted owls, has not colonized the study area. We used a Bayesian dynamic multistate model to evaluate if territory occupancy of reproductive spotted owls has declined as in other study areas. The state-space approach for dynamic multistate modeling imputes the number of territories for each nesting state and allows for the estimation of longer-term trends in occupied or reproductive territories from longitudinal studies. The multistate approach accounts for different detection probabilities by nesting state (to account for either inherent differences in detection or for the use of different survey methods for different occupancy states and reduces bias in state assignment. Estimated linear trends in the number of reproductive territories suggested an average loss of approximately one half territory per year (-0.55, 90% CRI: -0.76, -0.33, in one management block and a loss of 0.15 per year (-0.15, 90% CRI: -0.24, -0.07, in another management block during the 25 year observation period. Estimated trends in the third management block were also negative, but substantial uncertainty existed in the estimate (-0.09, 90% CRI: -0.35, 0.17. Our results indicate that the number of territories occupied by northern spotted owl pairs remained relatively constant over a 25 year period (-0.07, 90% CRI: -0.20, 0.05; -0.01, 90% CRI: -0.19, 0.16; -0.16, 90% CRI: -0.40, 0.06. However, we cannot exclude

  13. Multistate Models Reveal Long-Term Trends of Northern Spotted Owls in the Absence of a Novel Competitor.

    Science.gov (United States)

    Kroll, Andrew J; Jones, Jay E; Stringer, Angela B; Meekins, Douglas J

    2016-01-01

    Quantifying spatial and temporal variability in population trends is a critical aspect of successful management of imperiled species. We evaluated territory occupancy dynamics of northern spotted owls (Strix occidentalis caurina), California, USA, 1990-2014. The study area possessed two unique aspects. First, timber management has occurred for over 100 years, resulting in dramatically different forest successional and structural conditions compared to other areas. Second, the barred owl (Strix varia), an exotic congener known to exert significant negative effects on spotted owls, has not colonized the study area. We used a Bayesian dynamic multistate model to evaluate if territory occupancy of reproductive spotted owls has declined as in other study areas. The state-space approach for dynamic multistate modeling imputes the number of territories for each nesting state and allows for the estimation of longer-term trends in occupied or reproductive territories from longitudinal studies. The multistate approach accounts for different detection probabilities by nesting state (to account for either inherent differences in detection or for the use of different survey methods for different occupancy states) and reduces bias in state assignment. Estimated linear trends in the number of reproductive territories suggested an average loss of approximately one half territory per year (-0.55, 90% CRI: -0.76, -0.33), in one management block and a loss of 0.15 per year (-0.15, 90% CRI: -0.24, -0.07), in another management block during the 25 year observation period. Estimated trends in the third management block were also negative, but substantial uncertainty existed in the estimate (-0.09, 90% CRI: -0.35, 0.17). Our results indicate that the number of territories occupied by northern spotted owl pairs remained relatively constant over a 25 year period (-0.07, 90% CRI: -0.20, 0.05; -0.01, 90% CRI: -0.19, 0.16; -0.16, 90% CRI: -0.40, 0.06). However, we cannot exclude small

  14. Medium-Term Gas Market Report 2013: Market Trends and Projections to 2018

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    Global growth in natural gas use slowed measurably in 2012, although it still exceeded that of oil and total energy use. Among the headwinds facing gas are continuing weak demand in Europe, resilience of coal in North America as well as persistent bottlenecks and disruptions in the LNG value chain that in 2012 caused an exceptional global decline of LNG supply. At the same time, Asian demand for gas remains red-hot, and gas is beginning to gain traction as a transport fuel. The IEA new Medium-Term Gas Market Report provides a detailed analysis of demand, upstream investment and trade developments through 2018 that will shape the gas industry and the role of gas in the global energy system. Its special sections investigate the economic viability of gas-fired power generation in Europe, the prospects for an LNG trading hub in Asia as well as the potentially transformational role of natural gas in transport. Amid a continuous regional divergence between North American abundance, European weakness and Asian thirst for LNG, the 2013 Medium Term Gas Market Report will investigate the key questions that the gas industry faces. These include the prospect of the United States becoming a major gas exporter, the challenges of securing enough gas to meet China’s growth, and the ability of Russian gas – spurred both by weak EU demand and resurgent domestic production – to find its manifest destiny in Asia.

  15. Long-term effects of elevated ozone and UV-B radiation on vegetation and methane dynamics in northern peatland ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Morsky, S.K.

    2012-06-15

    In the stratosphere, ozone (O{sub 3}) forms an effective barrier against high energy ultraviolet radiation (UV), which is harmful to living cells. Despite the stratospheric O{sub 3} layer recovering due to international agreements, seasonal O{sub 3} depletion periods with high UV-B levels, may still occur, especially in the Polar regions. In the troposphere, O{sub 3} is a significant greenhouse gas contributing to global warming and also causing oxidative stress to animal- and plant cells. Global tropospheric O{sub 3} concentration has approximately doubled during the last century and the same trend is expected to continue. Northern peatlands are sinks of atmospheric carbon dioxide (CO{sub 2}) and sources of the powerful greenhouse gas methane (CH{sub 4}). Two multi-year open-field experiments were conducted to study the effects of elevated O{sub 3} concentration and UV-B radiation on peatland vegetation and CH{sub 4} dynamics in Finland. Peatland microcosms were used in the O{sub 3} experiment and the UV-B exposure study was conducted on a natural fen. Elevated O{sub 3} concentration significantly increased leaf cross-sections and the total number of Eriophorum vaginatum leaves towards the end of the experiment, but did not affect relative length growth, stomatal density or volume of aerenchymatous tissue of leaves. Elevated O{sub 3} did not affect relative length growth of Sphagnum papillosum shoots either. Concentrations of chlorophylls or carotenoids in E. vaginatum leaves or in S. papillosum shoots were not changed under elevated O{sub 3}. During the first growing season, elevated O{sub 3} concentration decreased methanol-extractable, UV-absorbing compounds in E. vaginatum leaves. Elevated O{sub 3} increased concentrations of organic acids and microbial biomass (estimated by phospholipid fatty acid biomarkers) in peat during the third growing season. In the first growing season net CH{sub 4} emission was temporarily decreased by elevated O{sub 3} concentration

  16. Long-Term Trends in Glaucoma-Related Blindness in Olmsted County, Minnesota

    Science.gov (United States)

    Malihi, Mehrdad; Moura Filho, Edney R.; Hodge, David O.; Sit, Arthur J.

    2013-01-01

    Objective To determine the longitudinal trends in the probability of blindness due to open-angle glaucoma (OAG) in Olmsted County, Minnesota from 1965 to 2009. Design Retrospective, population-based cohort study. Participants All residents of Olmsted County, Minnesota (40 years of age and over) who were diagnosed with OAG between January 1, 1965 to December 31, 2000. Methods All available medical records of every incident case of OAG were reviewed until December 31, 2009 to identify progression to blindness, defined as visual acuity of 20/200 or worse, and/or visual field constriction to 20° or less. Kaplan–Meier analysis was used to estimate the cumulative probability of glaucoma-related blindness. Population incidence of blindness within 10 years of diagnosis was calculated using United States Census data. Rates for subjects diagnosed in the period 1965–1980 were compared with rates for subjects diagnosed in the period 1981–2000 using logrank tests and Poisson regression models. Main Outcome Measures Cumulative probability of OAG-related blindness, and population incidence of blindness within 10 years of diagnosis. Results Probability of glaucoma-related blindness in at least one eye at 20 years decreased from 25.8 % (95% Confidence interval [CI]: 18.5–32.5) for subjects diagnosed in 1965–1980, to 13.5% (95% CI: 8.8–17.9) for subjects diagnosed in 1981–2000 (P=0.01). The population incidence of blindness within 10 years of the diagnosis decreased from 8.7 per 100,000 (95% CI: 5.9–11.5) for subjects diagnosed in 1965–1980, to 5.5 per 100,000 (95% CI: 3.9–7.2) for subjects diagnosed in 1981–2000 (P=0.02). Higher age at diagnosis was associated with increased risk of progression to blindness (Pblindness due to OAG in at least one eye have decreased over a 45 year period from 1965 to 2009. However, a significant proportion of patients still progress to blindness despite recent diagnostic and therapeutic advancements. PMID:24823760

  17. Changing trends in intestinal parasitic infections among long-term-residents and settled immigrants in Qatar

    Directory of Open Access Journals (Sweden)

    Doiphode Sanjay H

    2010-10-01

    Full Text Available Abstract Background The rapid socio-economic development in Qatar in the last two decades has encouraged a mass influx of immigrant workers, the majority of whom originate from countries with low socio-economic levels, inadequate medical care and many are known to carry patent intestinal helminth and protozoan infections on arrival in Qatar. Some eventually acquire residency status but little is known about whether they continue to harbour infections. Methods We examined 9208 hospital records of stool samples that had been analysed for the presence of intestinal helminth and protozoan ova/cysts, over the period 2005-2008, of subjects from 28 nationalities, but resident in Qatar and therefore not recent arrivals in the country. Results Overall 10.2% of subjects were infected with at least one species, 2.6% with helminths and 8.0% with protozoan species. Although hookworms, Ascaris lumbricoides, Trichuris trichiura and Hymenolepis nana were observed, the majority of helminth infections (69% were caused by hookworms, and these were largely aggregated among 20.0-39.9 year-old male subjects from Nepal. The remaining cases of helminth infection were mostly among Asian immigrants. Protozoan infections were more uniformly spread across immigrants from different regions when prevalence was calculated on combined data, but this disguised three quite contrasting underlying patterns for 3 taxa of intestinal protozoa. Blastocystis hominis, Giardia duodenalis and non-pathogenic amoebae were all acquired in childhood, but whereas prevalence of B. hominis rose to a plateau and then even further among the elderly, prevalence of G. duodenalis fell markedly in children aged 10 and older, and stayed low (Entamoeba coli, E. hartmanni, Endolimax nana and Iodamoeba buetschlii peaked in the 30.0-39.9 age group and only then dropped to very low values among the oldest subjects examined. A worrying trend in respect of both helminth and protozoan parasites was the

  18. Wheat Yield Trend and Soil Fertility Status in Long Term Rice-Rice-Wheat Cropping System

    Directory of Open Access Journals (Sweden)

    Nabin Rawal

    2015-12-01

    Full Text Available A long-term soil fertility experiment under rice-rice-wheat system was performed to evaluate the long term effects of inorganic fertilizer and manure applications on soil properties and grain yield of wheat. The experiment began since 1978 was laid out in randomized complete block design with 9 treatments replicated 3 times. From 1990 onwards, periodic modifications have been made in all the treatments splitting the plots in two equal halves of 4 x 3 m2 leaving one half as original. In the original treatments, recent data revealed that the use of Farm Yard Manure (FYM @10 t ha-1 gave significantly (P≤0.05 higher yield of 2.3 t ha-1 in wheat, whereas control plot gave the lowest grain yield of 277 kg ha-1. Similarly, in the modified treatments, the use of FYM @10 t ha-1 along with inorganic Nitrogen (N and Potassium oxide (K2O @ 50 kg ha-1 produced significantly (P≤0.05 the highest yield of 2.4 t/ha in wheat. The control plot with an indigenous nutrient supply only produced wheat yield of 277 kg ha-1 after 35th year completion of rice-rice-wheat system. A sharp decline in wheat yields was noted in minus N, phosphorus (P, Potassium (K treatments during recent years. Yields were consistently higher in the N:P2O5:K2O and FYM treatments than in treatments, where one or more nutrients were lacking. The application of P2O5 and K2O caused a partial recovery of yield in P and K deficient plots. There was significant (P≤0.05 effect of use of chemical fertilizers and manure on soil properties. The soil analysis data showed an improvement in soil pH (7.8, soil organic matter (4.1%, total N content (0.16%, available P (503.5 kg P2O5 ha-1 and exchangeable K (137.5 kg K2O ha-1 in FYM applied treatments over all other treatments. The findings showed that the productivity of the wheat can be increased and sustained by improving nutrient through the integrated use of organic and inorganic manures in long term.

  19. Medium-Term Oil Market Report 2013: Market Trends and Projections to 2018

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    The global oil market will undergo sweeping changes over the next five years. The 2013 Medium-Term Oil Market Report evaluates the impact of these changes on the global oil system by 2018 based on all that we know today – current expectations of economic growth, existing or announced policies and regulations, commercially proven technologies, field decline rates, investment programmes (upstream, midstream and downstream), etc. The five-year forecast period corresponds to the length of the typical investment cycle and as such is critical to policymakers and market participants. This Report shows, in detailed but concise terms, why the ongoing North American hydrocarbon revolution is a ''game changer''. The region’s expected contribution to supply growth, however impressive, is only part of the story: Crude quality, infrastructure requirements, current regulations, and the potential for replication elsewhere are bound to spark a chain reaction that will leave few links in the global oil supply chain unaffected. While North America is expected to lead medium-term supply growth, the East-of- Suez region is in the lead on the demand side. Non-OECD oil demand, led by Asia and the Middle East, looks set to overtake the OECD for the first time as early as 2Q13 and will widen its lead afterwards. Non-OECD economies are already home to over half global refining capacity. With that share only expected to grow by 2018, the non-OECD region will be firmly entrenched as the world’s largest crude importer. These and other changes are carefully laid out in this Report, which also examines recent and future changes in global oil storage, shifts in OPEC production capacity and crude and product trade, and the consequences of the ongoing refinery construction boom in emerging markets and developing economies. It is required reading for anyone engaged in policy or investment decision-making in the energy sphere, and those more broadly interested in the oil

  20. Modeling long-term yield trends of Miscanthusxgiganteus using experimental data from across Europe

    DEFF Research Database (Denmark)

    Lesur, Claire; Jeuffroy, Marie-Hélène; Makowski, David

    2013-01-01

    and the ceiling phases and (ii) to determine whether M. giganteus ceiling phase is followed by a decline phase where yields decrease across years. Data were analyzed through comparisons between a set of statistical growth models. The model that best fitted the experimental data included a decline phase....... The decline intensity and the value of several other model parameters, such as the maximum yield reached during the ceiling phase or the duration of the establishment phase, were highly variable. The highest maximum yields were obtained in the experiments located in the southern part of the studied area....... giganteus is known to have an establishment phase during which annual yields increased as a function of crop age, followed by a ceiling phase, the duration of which is unknown. We built a database including 16 European long-term experiments (i) to describe the yield evolution during the establishment...

  1. Long term trend analysis of emergency power diesel generator reliability in german nuclear power plants

    International Nuclear Information System (INIS)

    Kotthoff, K.; Maqua, M.

    1990-01-01

    The paper deals with a long-term investigation on the availability of diesel generators. This investigation has been performed in two steps in 1980/81 and 1988/89. It is based on the operating experiences of a total of 110 diesel generators in 20 German NPP's. The overall probability of diesel failure during start and short-time operation amounts to about 5E-3/demand. Compared to the result of the first part of the investigation (8E-3/demand) there has been some further improvement of diesel generator performance in recent years. The upper limit calculated for the probability of common mode failures (about 6E-4/demand) is approximately one order of magnitude smaller. The influence of various parameters on the failure probability has been discussed. A statistically significant dependence could not be identified

  2. New trends of short-term humanitarian medical volunteerism: professional and ethical considerations.

    Science.gov (United States)

    Asgary, Ramin; Junck, Emily

    2013-10-01

    Short-term humanitarian medical volunteerism has grown significantly among both clinicians and trainees over the past several years. Increasingly, both volunteers and their respective institutions have faced important challenges in regard to medical ethics and professional codes that should not be overlooked. We explore these potential concerns and their risk factors in three categories: ethical responsibilities in patient care, professional responsibility to communities and populations, and institutional responsibilities towards trainees. We discuss factors increasing the risk of harm to patients and communities, including inadequate preparation, the use of advanced technology and the translation of Western medicine, issues with clinical epidemiology and test utility, difficulties with the principles of justice and clinical justice, the lack of population-based medicine, sociopolitical effects of foreign aid, volunteer stress management, and need for sufficient trainee supervision. We review existing resources and offer suggestions for future skill-based training, organisational responsibilities, and ethical preparation.

  3. A Remote Sensing and GIS Approach to Study the Long-Term Vegetation Recovery of a Fire-Affected Pine Forest in Southern Greece

    Directory of Open Access Journals (Sweden)

    Foula Nioti

    2015-06-01

    Full Text Available Management strategies and silvicultural treatments of fire-prone ecosystems often rely on knowledge of the regeneration potential and long-term recovery ability of vegetation types. Remote sensing and GIS applications are valuable tools providing cost-efficient information on vegetation recovery patterns and their associated environmental factors. In this study we used an ordinal classification scheme to describe the land cover changes induced by a wildfire that occurred in 1983 in Pinus brutia woodlands on Karpathos Aegean Island, south-eastern Greece. As a proxy variable that indicates ecosystem recovery, we also estimated the difference between the NDVI and NBR indices a few months (1984 and almost 30 years after the fire (2012. Environmental explanatory variables were selected using a digital elevation model and various thematic maps. To identify the most influential environmental factors contributing to woodland recovery, binary logistic regression and linear regression techniques were applied. The analyses showed that although a large proportion of the P. brutia woodland has recovered 26 years after the fire event, a considerable amount of woodland had turned into scrub vegetation. Altitude, slope inclination, solar radiation, and pre-fire woodland physiognomy were identified as dominant factors influencing the vegetation’s recovery probability. Additionally, altitude and inclination are the variables that explain changes in the satellite remote sensing vegetation indices reflecting the recovery potential. Pinus brutia showed a good post-fire recovery potential, especially in parts of the study area with increased moisture availability.

  4. The effect of long-term irrigation using wastewater on heavy metal contents of soils under vegetables in Harare, Zimbabwe

    NARCIS (Netherlands)

    Mapanda, F.; Mangwayana, E.N.; Nyamangara, J.; Giller, K.E.

    2005-01-01

    The magnitude of contamination, regulatory compliance and annual loadings of soils with copper (Cu), zinc (Zn), cadmium (Cd), nickel (Ni), chromium (Cr) and lead (Pb) were determined at three sites in Harare where wastewater was used to irrigate vegetable gardens for at least 10 years. Heavy metal

  5. Repeatability of riparian vegetation sampling methods: how useful are these techniques for broad-scale, long-term monitoring?

    Science.gov (United States)

    Marc C. Coles-Ritchie; Richard C. Henderson; Eric K. Archer; Caroline Kennedy; Jeffrey L. Kershner

    2004-01-01

    Tests were conducted to evaluate variability among observers for riparian vegetation data collection methods and data reduction techniques. The methods are used as part of a largescale monitoring program designed to detect changes in riparian resource conditions on Federal lands. Methods were evaluated using agreement matrices, the Bray-Curtis dissimilarity metric, the...

  6. Vegetable processing wastes addition to improve swine manure anaerobic digestion: Evaluation in terms of methane yield and SEM characterization

    International Nuclear Information System (INIS)

    Molinuevo-Salces, Beatriz; González-Fernández, Cristina; Gómez, Xiomar; García-González, María Cruz; Morán, Antonio

    2012-01-01

    Highlights: ► Vegetable waste as co-substrate for swine manure anaerobic digestion. ► Two hydraulic retention times of 25 and 15 d, respectively. ► SEM characterization of anaerobic sludges to observe microbial composition. ► Vegetable waste as co-substrate increases methane yields up to three times. ► Microbial composition changes after 120 d of digestion. -- Abstract: The effect of adding vegetable waste as a co-substrate in the anaerobic digestion of swine manure was investigated. The study was carried out at laboratory scale using semi-continuous stirred tank reactors working at 37 °C. Organic loading rates (OLRs) of 0.4 and 0.6 g VS L −1 d −1 were evaluated, corresponding to hydraulic retention times (HRTs) of 25 and 15 d, respectively. The addition of vegetable wastes (50% dw/dw) resulted in an improvement of 3 and 1.4-fold in methane yields at HRTs of 25 and 15 d, respectively. Changes on microbial morphotypes were studied by Scanning Electron Microscopy (SEM). Samples analyzed were sludge used as inoculum and digestate obtained from swine manure anaerobic reactors. SEM pictures demonstrated that lignocellulosic material was not completely degraded. Additionally, microbial composition was found to change to cocci and rods morphotypes after 120 d of anaerobic digestion.

  7. Multiple scattering effects with cyclical terms in active remote sensing of vegetated surface using vector radiative transfer theory

    Science.gov (United States)

    The energy transport in a vegetated (corn) surface layer is examined by solving the vector radiative transfer equation using a numerical iterative approach. This approach allows a higher order that includes the multiple scattering effects. Multiple scattering effects are important when the optical t...

  8. Understanding Climate Change Impacts in a Cholera Endemic Megacity: Disease Trends, Hydroclimatic Indicators and Near Future-Term Projections

    Science.gov (United States)

    Akanda, A. S. S.; Hasan, M. A.; Serman, E. A.; Jutla, A.; Huq, A.; Colwell, R. R.

    2015-12-01

    The last three decades of surveillance data shows a drastic increase of cholera prevalence in the largest cholera-endemic city in the world - Dhaka, Bangladesh. While an endemic trend is getting stronger in the dry season, the post-monsoon season shows increased variability and is epidemic in nature. The pre-monsoon dry season is becoming the dominant cholera season of the year, followed by monsoon flood related propagation in later months of the year. Although the heavily populated and rapidly urbanizing Dhaka region has experienced noticeable shifts in pre monsoon temperature and precipitation patterns and subsequent monsoon variations, to date, there has not been any systematic study on linking the long-term disease trends with observed changes in hydroclimatic indicators. Here, we focus on the past 30-year dynamics of urban cholera prevalence in Dhaka with changes in climatic or anthropogenic forcings to develop projections for the next 30-year period. We focus on the dry and the wet season indicators individually, and develop trends of maximum rainfall intensity, lowest rainfall totals in the pre-monsoon period, number of consecutive dry days, number of wet days, and number of rainy days with greater than 500mm rainfall using a recently developed gridded data product - and compare with regional hydrology, flooding, water usage, changes in distribution systems, population growth and density in urban settlements, and frequency of natural disasters. We then use a bias correction method to develop the next 30 years projections of CMIP5 Regional Climate Model outputs and impacts on cholera prevalence using a probabilistic forecasting approach.

  9. Energy Efficiency Market Report 2013: Market Trends and Medium-Term Prospects

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    Energy efficiency has been referred to as a ''hidden fuel'', one that extends energy supplies, increases energy security, lowers carbon emissions and generally supports sustainable economic growth. Yet it is hiding in plain sight: in 2011, investments in the energy efficiency market globally were at a similar scale to those in renewable energy or fossil-fuel power generation. The Energy Efficiency Market Report provides a practical basis for understanding energy efficiency market activities, a review of the methodological and practical challenges associated with measuring the market and its components, and statistical analysis of energy efficiency and its impact on energy demand. It also highlights a specific technology sector in which there is significant energy efficiency market activity, in this instance appliances and ICT. The report presents a selection of country case studies that illustrate current energy efficiency markets in specific sectors, and how they may evolve in the medium term. The energy efficiency market is diffuse, varied and involves all energy-consuming sectors of the economy. A comprehensive overview of market activity is complicated by the challenges associated with quantifying the components of the market and the paucity of comparable reported data. This report underscores how vital high-quality and timely energy efficiency data is to understanding this market.

  10. Solar Cycle Response and Long-Term Trends in the Mesospheric Metal Layers

    Science.gov (United States)

    Dawkins, E. C. M.; Plane, J. M. C.; Chipperfield, M.; Feng, W.; Marsh, D. R.; Hoffner, J.; Janches, D.

    2016-01-01

    The meteoric metal layers (Na, Fe, and K) which form as a result of the ablation of incoming meteors act as unique tracers for chemical and dynamical processes that occur within the upper mesosphere lower thermosphere region. In this work, we examine whether these metal layers are sensitive Fe indicators of decadal long-term changes within the upper atmosphere. Output from a whole-atmosphere climate model is used to assess the response of the Na, K, and Fe layers across a 50 year period (1955-2005). At short timescales, the K layer has previously been shown to exhibit a very different seasonal behavior compared to the other metals. Here we show that this unusual behavior is also exhibited at longer time scales (both the 11 year solar cycle and 50 year periods), where K displays a much more pronounced response to atmospheric temperature changes than either Na or Fe. The contrasting solar cycle behavior of the K and Na layers predicted by the model is confirmed using satellite and lidar observations for the period 2004-2013.

  11. Long-term trends in nutrient budgets of the western Dutch Wadden Sea (1976-2012)

    Science.gov (United States)

    Jung, A. S.; Brinkman, A. G.; Folmer, E. O.; Herman, P. M. J.; van der Veer, H. W.; Philippart, C. J. M.

    2017-09-01

    Long-term field observations of nitrogen [N] and phosphorus [P] concentrations were used to construct nutrient budgets for the western Dutch Wadden Sea between 1976 and 2012. Nutrients come into the western Dutch Wadden Sea via river runoff, through exchange with the coastal zone of the North Sea, neighbouring tidal basins and through atmospheric deposition (for N). The highest concentrations in phosphorus and nitrogen were observed in the mid-1980s. Improved phosphorus removal at waste water treatment plants, management of fertilization in agriculture and removal of phosphates from detergents led to reduced riverine nutrient inputs and, consequently, reduced nutrient concentrations in the Wadden Sea. The budgets suggest that the period of the initial net import of phosphorus and nitrogen switched to a net export in 1981 for nitrogen and in 1992 for phosphorus. Such different behaviour in nutrient budgets during the rise and fall of external nutrient concentrations may be the result of different sediment-water exchange dynamics for P and N. It is hypothesized that during the period of increasing eutrophication (1976-1981) P, and to a lesser degree N, were stored in sediments as organic and inorganic nutrients. In the following period (1981-1992) external nutrient concentrations (especially in the North Sea) decreased, but P concentrations in the Wadden Sea remained high due to prolonged sediment release, whilst denitrification removed substantial amounts of N. From 1992 onwards, P and N budgets were closed by net loss, most probably because P stores were then depleted and denitrification continued. Under the present conditions (lower rates of sediment import and depleted P stores), nutrient concentrations in this area are expected to be more strongly influenced by wind-driven exchange with the North Sea and precipitation-driven discharge from Lake IJssel. This implies that the consequences of climate change will be more important, than during the 1970s and 1980s.

  12. Sex differences in lung cancer survival: long-term trends using population-based cancer registry data in Osaka, Japan.

    Science.gov (United States)

    Kinoshita, Fukuaki Lee; Ito, Yuri; Morishima, Toshitaka; Miyashiro, Isao; Nakayama, Tomio

    2017-09-01

    Several studies of sex differences in lung cancer survival have been reported. However, large-size population-based studies based on long-term observation are scarce. We investigated long-term trends in sex differences in lung cancer survival using population-based cancer registry data from Osaka, Japan. We analyzed 79 330 cases from the Osaka Cancer Registry (OCR) diagnosed between 1975 and 2007. We calculated 5-year relative survival in the six periods (1975-1980, 1981-1986, 1987-1992, 1993-1997, 1998-2002 and 2003-2007). To estimate the trends in sex differences in lung cancer survival throughout the study period, we applied a multivariate excess hazard model to control for confounders. The proportion of adenocarcinoma (ADC) and 5-year relative relative survival have increased for both sexes. Sex differences in lung cancer survival have widened over the period, especially in ADC and since the late 1990s. The excess hazard ratio of death within 5 years for males was 1.19 (95% CI: 1.16-1.21), adjusting for period at diagnosis, histologic type, stage, age group and treatment. We reported that females have better prognosis in lung cancer than males and the sex differences in lung cancer survival have become wider in Osaka, Japan. This can be partly explained by the sex differences in the proportions of histologic type and stage. Further studies considering other factors that influence sex differences in lung cancer survival are needed. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  13. Global changes in dryland vegetation dynamics (1988–2008 assessed by satellite remote sensing: comparing a new passive microwave vegetation density record with reflective greenness data

    Directory of Open Access Journals (Sweden)

    N. Andela

    2013-10-01

    Full Text Available Drylands, covering nearly 30% of the global land surface, are characterized by high climate variability and sensitivity to land management. Here, two satellite-observed vegetation products were used to study the long-term (1988–2008 vegetation changes of global drylands: the widely used reflective-based Normalized Difference Vegetation Index (NDVI and the recently developed passive-microwave-based Vegetation Optical Depth (VOD. The NDVI is sensitive to the chlorophyll concentrations in the canopy and the canopy cover fraction, while the VOD is sensitive to vegetation water content of both leafy and woody components. Therefore it can be expected that using both products helps to better characterize vegetation dynamics, particularly over regions with mixed herbaceous and woody vegetation. Linear regression analysis was performed between antecedent precipitation and observed NDVI and VOD independently to distinguish the contribution of climatic and non-climatic drivers in vegetation variations. Where possible, the contributions of fire, grazing, agriculture and CO2 level to vegetation trends were assessed. The results suggest that NDVI is more sensitive to fluctuations in herbaceous vegetation, which primarily uses shallow soil water, whereas VOD is more sensitive to woody vegetation, which additionally can exploit deeper water stores. Globally, evidence is found for woody encroachment over drylands. In the arid drylands, woody encroachment appears to be at the expense of herbaceous vegetation and a global driver is interpreted. Trends in semi-arid drylands vary widely between regions, suggesting that local rather than global drivers caused most of the vegetation response. In savannas, besides precipitation, fire regime plays an important role in shaping trends. Our results demonstrate that NDVI and VOD provide complementary information and allow new insights into dryland vegetation dynamics.

  14. Long-term trends of changes in pine and oak foliar nitrogen metabolism in response to chronic nitrogen amendments at Harvard Forest, MA

    Science.gov (United States)

    Rakesh Minocha; Swathi A. Turlapati; Stephanie Long; William H. McDowell; Subhash C. Minocha

    2015-01-01

    We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements...

  15. Long-term stabilization of uranium mill tailings: effects of rock material on vegetation on soil moisture

    International Nuclear Information System (INIS)

    Beedlow, P.A.; Carlile, D.W.

    1982-11-01

    A field-scale experiment was conducted to investigate the effects of pit-run rock and washed cobble on vegetation and soil moisture. The success of various seed mixtures, transplanting and irrigation levels were evaluated. Total cover changed negligibly from the first growing season to the next, but the structure of the vegetation changed markedly. Moderate levels of irrigation increased the establishment of perennial grasses and shrubs. Rock placed on the surface prior to planting resulted in increased cover of weeds, shrubs and forbs and decreased grass cover relative to soil without surface rock. The most successful seed mixture was one of predominantly shrub and forb species adapted to the local environment. No significant differences in soil moisture were found between surface cover types. 6 references, 7 figures

  16. Post-eruption legacy effects and their implications for long-term recovery of the vegetation on Kasatochi Island, Alaska

    Science.gov (United States)

    Talbot, S. S.; Talbot, S.L.; Walker, L.R.

    2010-01-01

    We studied the vegetation of Kasatochi Island, central Aleutian Islands, to provide a general field assessment regarding the survival of plants, lichens, and fungi following a destructive volcanic eruption that occurred in 2008. Plant community data were analyzed using multivariate methods to explore the relationship between pre- and post-eruption plant cover; 5 major vegetation types were identified: Honckenya peploides beach, Festuca rubra cliff shelf, Lupinus nootkatensisFestuca rubra meadow, Leymus mollis bluff ridge (and beach), and Aleuria aurantia lower slope barrens. Our study provided a very unusual glimpse into the early stages of plant primary succession on a remote island where most of the vegetation was destroyed. Plants that apparently survived the eruption dominated early plant communities. Not surprisingly, the most diverse post-eruption community most closely resembled a widespread pre-eruption type. Microhabitats where early plant communities were found were distinct and apparently crucial in determining plant survival. Comparison with volcanic events in related boreal regions indicated some post-eruption pattern similarities. ?? 2010 Regents of the University of Colorado.

  17. A long-term vegetation history of the Mojave-Colorado Desert ecotone at Joshua Tree National Park

    Science.gov (United States)

    Holmgren, Camille A.; Betancourt, Julio L.; Rylander, Kate A.

    2010-01-01

    Thirty-eight dated packrat middens were collected from upper desert (930–1357 m) elevations within Joshua Tree National Park near the ecotone between the Mojave Desert and Colorado Desert, providing a 30 ka record of vegetation change with remarkably even coverage for the last 15 ka. This record indicates that vegetation was relatively stable, which may reflect the lack of invasion by extralocal species during the late glacial and the early establishment and persistence of many desert scrub elements. Many of the species found in the modern vegetation assemblages were present by the early Holocene, as indicated by increasing Sørenson's Similarity Index values. C4 grasses and summer-flowering annuals arrived later at Joshua Tree National Park in the early Holocene, suggesting a delayed onset of warm-season monsoonal precipitation compared to other Sonoran Desert and Chihuahuan Desert localities to the east, where summer rains and C4 grasses persisted through the last glacial–interglacial cycle. This would suggest that contemporary flow of monsoonal moisture into eastern California is secondary to the core processes of the North American Monsoon, which remained intact throughout the late Quaternary. In the Holocene, northward displacement of the jet stream, in both summer and winter, allowed migration of the subtropical ridge as far north as southern Idaho and the advection of monsoonal moisture both westward into eastern California and northward into the southern Great Basin and Colorado Plateau.

  18. Comment on “Long-term trends in thermospheric neutral temperatures and density above Millstone Hill” by W. L. Oliver et al

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan

    2015-01-01

    Roč. 120, č. 3 (2015), s. 2347-2349 ISSN 2169-9380 R&D Projects: GA ČR GAP209/10/1792; GA ČR GA15-03909S Institutional support: RVO:68378289 Keywords : ionosphere * thermosphere * long-term trends * drivers of trends Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 3.318, year: 2015 http://onlinelibrary.wiley.com/doi/10.1002/2014JA020864/abstract

  19. Drivers for spatial, temporal and long-term trends in atmospheric ammonia and ammonium in the UK

    Directory of Open Access Journals (Sweden)

    Y. S. Tang

    2018-01-01

    Full Text Available A unique long-term dataset from the UK National Ammonia Monitoring Network (NAMN is used here to assess spatial, seasonal and long-term variability in atmospheric ammonia (NH3: 1998–2014 and particulate ammonium (NH4+: 1999–2014 across the UK. Extensive spatial heterogeneity in NH3 concentrations is observed, with lowest annual mean concentrations at remote sites (< 0.2 µg m−3 and highest in the areas with intensive agriculture (up to 22 µg m−3, while NH4+ concentrations show less spatial variability (e.g. range of 0.14 to 1.8 µg m−3 annual mean in 2005. Temporally, NH3 concentrations are influenced by environmental conditions and local emission sources. In particular, peak NH3 concentrations are observed in summer at background sites (defined by 5 km grid average NH3 emissions < 1 kg N ha−1 yr−1 and in areas dominated by sheep farming, driven by increased volatilization of NH3 in warmer summer temperatures. In areas where cattle, pig and poultry farming is dominant, the largest NH3 concentrations are in spring and autumn, matching periods of manure application to fields. By contrast, peak concentrations of NH4+ aerosol occur in spring, associated with long-range transboundary sources. An estimated decrease in NH3 emissions by 16 % between 1998 and 2014 was reported by the UK National Atmospheric Emissions Inventory. Annually averaged NH3 data from NAMN sites operational over the same period (n =  59 show an indicative downward trend, although the reduction in NH3 concentrations is smaller and non-significant: Mann–Kendall (MK, −6.3 %; linear regression (LR, −3.1 %. In areas dominated by pig and poultry farming, a significant reduction in NH3 concentrations between 1998 and 2014 (MK: −22 %; LR: −21 %, annually averaged NH3 is consistent with, but not as large as the decrease in estimated NH3 emissions from this sector over the same period (−39 %. By contrast, in cattle

  20. Summary of preliminary step-trend analysis from the Interagency Whitebark Pine Long-termMonitoring Program—2004-2013

    Science.gov (United States)

    Legg, Kristin; Shanahan, Erin; Daley, Rob; Irvine, Kathryn M.

    2014-01-01

    In mixed and dominant stands, whitebark pine (Pinus albicaulis) occurs in over two million acres within the six national forests and two national parks that comprise the Greater Yellowstone Ecosystem (GYE). Currently, whitebark pine, an ecologically important species, is impacted by multiple ecological disturbances; white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus ponderosae), wildfire, and climate change all pose significant threats to the persistence of whitebark pine populations. Substantial declines in whitebark pine populations have been documented throughout its range.Under the auspices of the Greater Yellowstone Coordinating Committee (GYCC), several agencies began a collaborative, long-term monitoring program to track and document the status of whitebark pine across the GYE. This alliance resulted in the formation of the Greater Yellowstone Whitebark Pine Monitoring Working Group (GYWPMWG), which consists of representatives from the U.S. Forest Service (USFS), National Park Service (NPS), U.S. Geological Survey (USGS), and Montana State University (MSU). This groundbased monitoring program was initiated in 2004 and follows a peer-reviewed protocol (GYWPMWG 2011). The program is led by the Greater Yellowstone Inventory and Monitoring Network (GRYN) of the National Park Service in coordination with multiple agencies. More information about this monitoring effort is available at: http://science. nature.nps.gov/im/units/gryn/monitor/whitebark_pine.cfm. The purpose of this report is to provide a draft summary of the first step-trend analysis for the interagency, long-term monitoring of whitebark pine health to the Interagency Grizzly Bear Study Team (IGBST) as part of a synthesis of the state of whitebark pine in the GYE. Due to the various stages of the analyses and reporting, this is the most efficient way to provide these results to the IGBST.

  1. Evaluation of long-term trends in hydrographic and nutrient parameters in a southeast US coastal river.

    Science.gov (United States)

    Williams, Asher A; Kimball, Matthew E

    2013-12-01

    The Nassau River estuary is located in northeast Florida adjacent to the eutrophic St. Johns River. Historically, development has been sparse in the Nassau River's catchment; thus, the system may provide a relatively undisturbed aquatic environment. To monitor the condition of the Nassau River estuary and to discern spatial and temporal trends in water quality, nutrients and hydrographic variables were assessed throughout the estuary from 1997 to 2011. Hydrographic (temperature, salinity, total suspended solids, and turbidity) and nutrient parameters (total phosphorus, ortho-PO₄(3-), total nitrogen, NH₄(+), total Kjeldahl nitrogen, and NO₃(-)) were monitored bimonthly at 12 sites in the mesohaline and polyhaline zones of the river. Nonparametric Kendall's Tau was implemented to analyze long-term water quality patterns. Salinity was found to increase with time, particularly in the mesohaline sampling sites. Dissolved oxygen decreased over time in the estuary and hypoxic conditions became increasingly frequent in the final years of the study. Nutrients increased in the estuary, ranging from 149 to 401%. Rainfall data collected in adjacent conservation areas did not correlate well with nutrients as compared with stream discharge data collected in the basin headwaters, outside of the conservation lands, attributed here to expanding urbanization. During the study period, the Nassau basin underwent rapid human population growth and land development resulting in commensurate impacts to water quality. Nutrient and physical data collected during this study indicate that the Nassau River estuary is becoming more eutrophic with time.

  2. Long-term deforestation in NW Spain: linking the Holocene fire history to vegetation change and human activities

    Science.gov (United States)

    Kaal, Joeri; Carrión Marco, Yolanda; Asouti, Eleni; Martín Seijo, Maria; Martínez Cortizas, Antonio; Costa Casáis, Manuela; Criado Boado, Felipe

    2011-01-01

    The Holocene fire regime is thought to have had a key role in deforestation and shrubland expansion in Galicia (NW Spain) but the contribution of past societies to vegetation burning remains poorly understood. This may be, in part, due to the fact that detailed fire records from areas in close proximity to archaeological sites are scarce. To fill this gap, we performed charcoal analysis in five colluvial soils from an archaeological area (Campo Lameiro) and compared the results to earlier studies from this area and palaeo-ecological literature from NW Spain. This analysis allowed for the reconstruction of the vegetation and fire dynamics in the area during the last ca 11 000 yrs. In the Early Holocene, Fabaceae and Betula sp. were dominant in the charcoal record. Quercus sp. started to replace these species around 10 000 cal BP, forming a deciduous forest that prevailed during the Holocene Thermal Maximum until ˜5500 cal BP. Following that, several cycles of potentially fire-induced forest regression with subsequent incomplete recovery eventually led to the formation of an open landscape dominated by shrubs (Erica sp. and Fabaceae). Major episodes of forest regression were (1) ˜5500-5000 cal BP, which marks the mid-Holocene cooling after the Holocene Thermal Maximum, but also the period during which agropastoral activities in NW Spain became widespread, and (2) ˜2000-1500 cal BP, which corresponds roughly to the end of the Roman Warm Period and the transition from the Roman to the Germanic period. The low degree of chronological precision, which is inherent in fire history reconstructions from colluvial soils, made it impossible to distinguish climatic from human-induced fires. Nonetheless, the abundance of synanthropic pollen indicators (e.g. Plantago lanceolata and Urtica dioica) since at least ˜6000 cal BP strongly suggests that humans used fire to generate and maintain pasture.

  3. Probing the Gaps: A Synthesis of Well-known and Lesser-known Hydrological Feedbacks Influencing Vegetation Patterning and Long-term Geomorphic Change in Low-gradient Fluvial Landscapes

    Science.gov (United States)

    Larsen, L.; Christensen, A.; Harvey, J. W.; Ma, H.; Newman, S.; Saunders, C.; Twilley, R.

    2017-12-01

    Emergence of vegetation patterning in fluvial landscapes is a classic example of how autogenic processes can drive long term fluvial and geomorphic adjustments in aquatic ecosystems. Studies elucidating the physics of flow through vegetation patches have produced understanding of how patterning in topography and vegetation commonly emerges and what effect it has on long term geomorphic change. However, with regard to mechanisms underlying pattern existence and resilience, several knowledge gaps remain, including the role of landscape-scale flow-vegetation feedbacks, feedbacks that invoke additional biogeochemical or biological agents, and determination of the relative importance of autogenic processes relative to external drivers. Here we provide a synthesis of the processes over a range of scales known to drive vegetation patterning and sedimentation in low gradient fluvial landscapes, emphasizing recent field and modeling studies in the Everglades, FL and Wax Lake Delta, LA that address these gaps. In the Everglades, while flow routing and sediment redistribution at the patch scale is known to be a primary driver of vegetation pattern emergence, landscape-scale routing of flow, as driven by the landscape's connectivity, can set up positive feedbacks that influence the rate of pattern degradation. Recent flow release experiments reveal that an additional feedback, involving phosphorus concentrations, flow, and floating vegetation communities that are abundant under low phosphorus, low flow conditions further stabilizes the alternative landscape states established through local scale sediment redistribution. Biogeochemistry-vegetation-sediment feedbacks may also be important for geomorphic development of newly emerging landscapes such as the Wax Lake Delta. There, fine sediment deposition shapes hydrogeomorphic zones with vegetation patterns that stimulate the growth of biofilm, while biofilm characteristics override the physical characteristics of vegetation

  4. Long-term trends and survival analysis of esophageal and gastric cancer in Yangzhong, 1991-2013.

    Directory of Open Access Journals (Sweden)

    Zhaolai Hua

    Full Text Available To describe the long-term trends of the incidence, mortality and survival of upper digestive tract cancers in a high-risk area of China.We extracted esophageal and gastric cancer cases diagnosed from 1991 to 2013 through the Yangzhong Cancer Registry and calculated the crude and age-standardized incidence and mortality rates. Cancer trends were calculated using the Joinpoint Regression Program and were reported using the annual percentage change (APC. The cancer-specific survival rates were evaluated and compared between groups using the Kaplan-Meier method and log-rank test.The age-standardized incidence rate of esophageal cancer declined from 107.06 per 100,000 person-years (male: 118.05 per 100,000 person-years; female: 97.42 per 100,000 person-years in 1991 to 37.04 per 100,000 person-years (male: 46.43 per 100,000 person-years; female: 27.26 per 100,000 person-years in 2013, with an APC of -2.5% (95% confidence interval (CI: -3.4%, -1.5% for males and -4.9% (95% CI:-5.8%, -3.9% for females. The age-standardized incidence rate of gastric cancer was 165.11 per 100,000 person-years (male: 225.39 per 100,000 person-years; female: 113.34 per 100,000 person-years in 1991 and 53.46 per 100,000 person-years (male: 76.51 per 100,000 person-years; female: 32.43 per 100,000 person-years in 2013, with the APC of -3.6% (95% CI: -4.5%, -2.7% for males and -4.8% (95% CI: -5.7%, -3.9% for females. The median survival time was 3.0 years for patients with esophageal or gastric cancer. Cancer cases detected after 2004 had a better prognosis.The age-standardized incidence rates of both esophageal and gastric cancer continuously decreased since 1991 through 2013, whereas the mortality rate remained stable before 2004 and significantly declined following the massive endoscopic screening program initiated in 2004. The survival probability of patients with esophageal and gastric cancer has improved obviously in recent decades.

  5. Climatic drivers of vegetation based on wavelet analysis

    Science.gov (United States)

    Claessen, Jeroen; Martens, Brecht; Verhoest, Niko E. C.; Molini, Annalisa; Miralles, Diego

    2017-04-01

    Vegetation dynamics are driven by climate, and at the same time they play a key role in forcing the different bio-geochemical cycles. As climate change leads to an increase in frequency and intensity of hydro-meteorological extremes, vegetation is expected to respond to these changes, and subsequently feed back on their occurrence. This response can be analysed using time series of different vegetation diagnostics observed from space, in the optical (e.g. Normalised Difference Vegetation Index (NDVI), Solar Induced Fluorescence (SIF)) and microwave (Vegetation Optical Depth (VOD)) domains. In this contribution, we compare the climatic drivers of different vegetation diagnostics, based on a monthly global data-cube of 24 years at a 0.25° resolution. To do so, we calculate the wavelet coherence between each vegetation-related observation and observations of air temperature, precipitation and incoming radiation. The use of wavelet coherence allows unveiling the scale-by-scale response and sensitivity of the diverse vegetation indices to their climatic drivers. Our preliminary results show that the wavelet-based statistics prove to be a suitable tool for extracting information from different vegetation indices. Going beyond traditional methods based on linear correlations, the application of wavelet coherence provides information about: (a) the specific periods at which the correspondence between climate and vegetation dynamics is larger, (b) the frequencies at which this correspondence occurs (e.g. monthly or seasonal scales), and (c) the time lag in the response of vegetation to their climate drivers, and vice versa. As expected, areas of high rainfall volumes are characterised by a strong control of radiation and temperature over vegetation. Furthermore, precipitation is the most important driver of vegetation variability over short terms in most regions of the world - which can be explained by the rapid response of leaf development towards available water content

  6. The six year report: Acidification of surface water in Europe and North America. Dose/response relationships and long-term trends

    Energy Technology Data Exchange (ETDEWEB)

    Skjelkvaale, B L; Newell, A D; Raddum, G; Johannessen, M; Hovind, H; Tjomsland, T; Wathne, B M

    1994-12-31

    This report discusses The International Cooperative Programme on Assessment and Monitoring of Acidification of Rivers and Lakes, which is designed to (1) establish degree and extent of acidification of surface waters, (2) evaluate dose/response relationships and (3) define long-term trends and variations in aquatic chemistry and biota attributable to atmospheric pollution. Data from 200 sites in 14 countries of Europe and North America are available. Dose/response relationships show that the fauna is adapted to different water qualities in different regions, and that critical limits for the fauna must be calculated according to data for the specific region. Long-term trends of water chemistry show decreases in SO{sub 4}{sup 2-} and Ca{sup 2+} at many sites. Nitrate shows no consistent trends. 66 refs., 26 figs., 16 tabs.

  7. Comments on "Long-Term Variations of Exospheric Temperature Inferred From foF1 Observations: A Comparison to ISR Ti Trend Estimates" by Perrone and Mikhailov

    Science.gov (United States)

    Zhang, Shun-Rong; Holt, John M.; Erickson, Philip J.; Goncharenko, Larisa P.

    2018-05-01

    Perrone and Mikhailov (2017, https://doi.org/10.1002/2017JA024193) and Mikhailov et al. (2017, https://doi.org/10.1002/2017JA023909) have recently examined thermospheric and ionospheric long-term trends using a data set of four thermospheric parameters (Tex, [O], [N2], and [O2]) and solar EUV flux. These data were derived from one single ionospheric parameter, foF1, using a nonlinear fitting procedure involving a photochemical model for the F1 peak. The F1 peak is assumed at the transition height ht with the linear recombination for atomic oxygen ions being equal to the quadratic recombination for molecular ions. This procedure has a number of obvious problems that are not addressed or not sufficiently justified. The potentially large ambiguities and biases in derived parameters make them unsuitable for precise quantitative ionospheric and thermospheric long-term trend studies. Furthermore, we assert that Perrone and Mikhailov (2017, https://doi.org/10.1002/2017JA024193) conclusions regarding incoherent scatter radar (ISR) ion temperature analysis for long-term trend studies are incorrect and in particular are based on a misunderstanding of the nature of the incoherent scatter radar measurement process. Large ISR data sets remain a consistent and statistically robust method for determining long term secular plasma temperature trends.

  8. Long-term trends of black carbon and sulphate aerosol in the Arctic: changes in atmospheric transport and source region emissions

    Directory of Open Access Journals (Sweden)

    D. Hirdman

    2010-10-01

    Full Text Available As a part of the IPY project POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols and Transport and building on previous work (Hirdman et al., 2010, this paper studies the long-term trends of both atmospheric transport as well as equivalent black carbon (EBC and sulphate for the three Arctic stations Alert, Barrow and Zeppelin. We find a general downward trend in the measured EBC concentrations at all three stations, with a decrease of −2.1±0.4 ng m−3 yr−1 (for the years 1989–2008 and −1.4±0.8 ng m−3 yr−1 (2002–2009 at Alert and Zeppelin respectively. The decrease at Barrow is, however, not statistically significant. The measured sulphate concentrations show a decreasing trend at Alert and Zeppelin of −15±3 ng m−3 yr−1 (1985–2006 and −1.3±1.2 ng m−3 yr−1 (1990–2008 respectively, while there is no trend detectable at Barrow.

    To reveal the contribution of different source regions on these trends, we used a cluster analysis of the output of the Lagrangian particle dispersion model FLEXPART run backward in time from the measurement stations. We have investigated to what extent variations in the atmospheric circulation, expressed as variations in the frequencies of the transport from four source regions with different emission rates, can explain the long-term trends in EBC and sulphate measured at these stations. We find that the long-term trend in the atmospheric circulation can only explain a minor fraction of the overall downward trend seen in the measurements of EBC (0.3–7.2% and sulphate (0.3–5.3% at the Arctic stations. The changes in emissions are dominant in explaining the trends. We find that the highest EBC and sulphate concentrations are associated with transport from Northern Eurasia and decreasing emissions in this region drive the

  9. Temporal Changes in Coupled Vegetation Phenology and Productivity are Biome-Specific in the Northern Hemisphere

    Directory of Open Access Journals (Sweden)

    Lanhui Wang

    2017-12-01

    Full Text Available Global warming has greatly stimulated vegetation growth through both extending the growing season and promoting photosynthesis in the Northern Hemisphere (NH. Analyzing the combined dynamics of such trends can potentially improve our current understanding on changes in vegetation functioning and the complex relationship between anthropogenic and climatic drivers. This study aims to analyze the relationships (long-term trends and correlations of length of vegetation growing season (LOS and vegetation productivity assessed by the growing season NDVI integral (GSI in the NH (>30°N to study any dependency of major biomes that are characterized by different imprint from anthropogenic influence. Spatial patterns of converging/diverging trends in LOS and GSI and temporal changes in the coupling between LOS and GSI are analyzed for major biomes at hemispheric and continental scales from the third generation Global Inventory Monitoring and Modeling Studies (GIMMS Normalized Difference Vegetation Index (NDVI dataset for a 32-year period (1982–2013. A quarter area of the NH is covered by converging trends (consistent significant trends in LOS and GSI, whereas diverging trends (opposing significant trends in LOS and GSI cover about 6% of the region. Diverging trends are observed mainly in high latitudes and arid/semi-arid areas of non-forest biomes (shrublands, savannas, and grasslands, whereas forest biomes and croplands are primarily characterized by converging trends. The study shows spatially-distinct and biome-specific patterns between the continental land masses of Eurasia (EA and North America (NA. Finally, areas of high positive correlation between LOS and GSI showed to increase during the period of analysis, with areas of significant positive trends in correlation being more widespread in NA as compared to EA. The temporal changes in the coupled vegetation phenology and productivity suggest complex relationships and interactions that are induced

  10. Long-Term Arctic Peatland Dynamics, Vegetation and Climate History of the Pur-Taz Region, Western Siberia

    Science.gov (United States)

    Peteet, Dorothy; Andreev, Andrei; Bardeen, William; Mistretta, Francesca

    1998-01-01

    Stratigraphic analyses of peat composition, LOI, pollen, spores, macrofossils, charcoal, and AMS ages are used to reconstruct the peatland, vegetation and climatic dynamics in the Pur-Taz region of western Siberia over 5000 years (9300 - 4500 BP). Section stratigraphy shows many changes from shallow lake sediment to different combinations of forested or open sedge, moss, and Equisetum fen and peatland environments. Macrofossil and pollen data indicate that Larix sibirica and Betula pubescens trees were first to arrive, followed by Picea obovata. The dominance of Picea macrofossils 6000-5000 BP in the Pur-Taz peatland along with regional Picea pollen maxima indicate warmer conditions and movement of the spruce treeline northward at this time. The decline of pollen and macrofossils from all of these tree species in uppermost peats suggests a change in the environment less favorable for their growth, perhaps cooler temperatures and/or less moisture. Of major significance is the evidence for old ages of the uppermost peats in this area of Siberia, suggesting a real lack of peat accumulation in recent millennia or recent oxidation of uppermost peat.

  11. Vegetation Dynamics in the Upper Guinean Forest Region of West Africa from 2001 to 2015

    Directory of Open Access Journals (Sweden)

    Zhihua Liu

    2016-12-01

    Full Text Available The Upper Guinea Forest (UGF region of West Africa is one of the most climatically marginal and human-impacted tropical forest regions in the world. Research on the patterns and drivers of vegetation change is critical for developing strategies to sustain ecosystem services in the region and to understand how climate and land use change will affect other tropical forests around the globe. We compared six spectral indices calculated from the 2001–2015 MODIS optical-infrared reflectance data with manually-interpreted measurements of woody vegetation cover from high resolution imagery. The tasseled cap wetness (TCW index was found to have the strongest association with woody vegetation cover, whereas greenness indices, such as the enhanced vegetation index (EVI, had relatively weak associations with woody cover. Trends in woody vegetation cover measured with the TCW index were analyzed using Mann–Kendall statistics and were contrasted with trends in vegetation greenness measured with EVI. In the drier West Sudanian Savanna and Guinean Forest-Savanna Mosaic ecoregions, EVI trends were primarily positive, and TCW trends were primarily negative, suggesting that woody vegetation cover was decreasing, while herbaceous vegetation cover is increasing. In the wettest tropical forests in the Western Guinean Lowland Forest ecoregion, declining trends in both TCW and EVI were indicative of widespread forest degradation resulting from human activities. Across all ecoregions, declines in woody cover were less prevalent in protected areas where human activities were restricted. Multiple lines of evidence suggested that human land use and resource extraction, rather than climate trends or short-term climatic anomalies, were the predominant drivers of recent vegetation change in the UGF region of West Africa.

  12. Long-Term Trends in Marriage Timing and the Impact of Migration, the Netherlands (1650-1899

    Directory of Open Access Journals (Sweden)

    Charlotte Störmer

    2017-12-01

    Full Text Available The features of historical marriage patterns have been linked to debates in social and economic history about economic growth and female agency. However, there is a lack of empirical evidence on the demographics of marriage prior to the nineteenth century. Here, we study trends in sex-specific ages at first marriage, regional variation and the impact of migration on marital timing in the Netherlands in the period 1650-1900. We make use of two new large historical datasets, namely an aggregation of Dutch genealogies and the transcribed marriage banns of Amsterdam. This allows us to understand the features and developments of marriage ages from a long-term perspective in what is known as one of the core-areas of the so-called European Marriage Pattern. Our results show high marriage ages for both sexes from the beginning of our study period, increasing until the mid-19th century. A closer look at regional variation reveals clear differences between the provinces and between urban and rural settings with those in the western part of the country and in urban centers marrying earlier. Migrating individuals married on average later than non-migrating individuals both compared to men and women in the receiving community, as to the ‘stayers’ in the location of origin. As later marriage implies a reduction of the window of fertility, especially for women, our results suggest that migration and increasing regional mobility might have been an important driver of the demographic shift toward higher marriage ages and lower fertility in Europe between the 17th and 19th centuries.

  13. Drivers, trends, and potential impacts of long-term coastal reclamation in China from 1985 to 2010

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Bo; Wu, Wenting; Yang, Zhaoqing; Zhou, Yunxuan

    2016-03-01

    Driven by rapid economic development, population growth, and urbanization, China has experienced severe coastal land reclamation over the last decades, which resulted in significant loss of coastal wetland and wildlife habitat, and degradation of marine ecosystems. This study used advanced remote-sensing techniques to analyze the spatial and temporal distributions of coastal reclamation in China and investigated the relationships between coastal land reclamation and coastal economy, population growth, and urbanization. Analysis of long-term Landsat images time series from 1985 to 2010 in 5-year intervals, in combination with remotely sensed image techniques, indicated a sharp increasing trend of land reclamation after 2005, which accounted for over 35% of China’s total reclamation during the 25-year period since 1985. High-intensity coastal reclamation in China was mainly driven by the booming economy associated with urbanization and industrial development in the coastal region. Analysis indicated that coastal land reclamation is closely correlated with the GDP per capita in China. Study results of Landsat images showed that 754,697 ha of coastal wetlands have been reclaimed across all coastal provinces and metropolises from 1985 to 2010, at an annual rate of 5.9%. Coastal areas within the three major economic zones (Bohai Bay, Yangtze River Delta, and Pearl River Delta) were found to generally have higher reclamation rates. For example, the built-up area in Shanghai, which is located in the Yangtze River Delta, increased more than five times from 1985 to 2010. Approximately 35% of the reclamation occurred in Bohai Bay, in which the CRI between 2005 and 2010 was three times higher than the average CRI over the 25-year period.

  14. Organic tritium in freshwater ecosystems: long-term trends in the environment of French nuclear power plants

    International Nuclear Information System (INIS)

    Gontier, G.; Siclet, F.

    2011-01-01

    From 1977 to 2009, more than 600 measurements of organic tritium were performed on fish, aquatic plants and sediments upstream and downstream of the 15 French NPP located along rivers. Examination of the results shows that organic tritium activities have exponentially decreased over the last thirty years, in all components of aquatic ecosystems. Upstream of all NPP, OBT levels in sediments are higher than in plants and fish, themselves larger than HTO in surface water. The magnitude of these differences and the long-term trends depend on the river basin and can be explained by the varying nature of tritium sources. In river catchment, where atmospheric test fallout is the main source of tritium, the observed levels result from the exposure of aquatic organisms to two distinct tritium pools of different ages: atmospheric tritiated water (representing present fallout), and organic tritium from soils (formed over several decades) which supplies particulate matter to surface waters. In the Rhone and Rhine river basins, an additional source of organic tritium of very low bio-availability, probably originating from the luminescent paint industry, is responsible for the spiking of sediment organic matter up to 100 to 100 000 Bq.L -1 combustion water. The comparison of upstream and downstream NPP tritium levels shows that the influence of tritium discharges is detectable only in rivers, with low background OBT activities, i.e in basins other than the Rhone and Rhine. The observed increase in plant and fish OBT is lower than the added HTO activity in water due to discharge, which supports the absence of bioaccumulation for tritium originating from HTO and the absence of highly bio-available tritiated organic molecules in NPP discharges. (authors)

  15. Decoupling of stream and vegetation solutes during the late stages of weathering: insights from elemental and Mg isotope trends at the Luquillo Critical Zone Observatory, Puerto Rico

    Science.gov (United States)

    Chapela Lara, M.; Schuessler, J. A.; Buss, H. L.; McDowell, W. H.

    2017-12-01

    During the evolution of the critical zone, the predominant source of nutrients to the vegetation changes from bedrock weathering to atmospheric inputs and biological recycling. In parallel, the architecture of the critical zone changes with time, promoting a change in water flow regime from near-surface porous flow during early weathering stages to more complex flow regimes modulated by clay-rich regolith during the late stages of weathering. As a consequence of these two concurrent processes, we can expect the predominant sources and pathways of solutes to the streams to also change during critical zone evolution. If this is true, we would observe a decoupling between the solutes used by the vegetation and those that determine the composition of the streams during the late stages of weathering, represented by geomorphically stable tropical settings. To test these hypotheses, we are analyzing the elemental and Mg isotopic composition of regolith and streams at the humid tropical Luquillo Critical Zone Observatory. We aim to trace the relative contributions of the surficial, biologically mediated pathways and the deeper, weathering controlled nutrient pathways. We also investigate the role of lithology on the solute decoupling between the vegetation and the stream, by examining two similar headwater catchments draining two different bedrocks (andesitic volcaniclastic and granitic). Our preliminary elemental and Mg isotope results are consistent with atmospheric inputs in the upper 2 m of regolith in both lithologies and with bedrock weathering at depth. During a short storm event ( 6 h), a headwater stream draining volcaniclastic bedrock showed a large variation in Mg and δ26Mg, correlated with total suspended solids, while another similar headwater granitic stream showed a much narrower variation. A larger stream draining volcaniclastic bedrock showed changes in Mg concentration in response to rain during the same storm event, but did not change in δ26Mg

  16. Coevolution of nonlinear trends in vegetation, soils, and topography with elevation and slope aspect: A case study in the sky islands of southern Arizona

    Science.gov (United States)

    Pelletier, Jon D.; Barron-Gafford, Greg A.; Breshears, David D.; Brooks, Paul D.; Chorover, Jon; Durcik, Matej; Harman, Ciaran J.; Huxman, Travis E.; Lohse, Kathleen A.; Lybrand, Rebecca; Meixner, Tom; McIntosh, Jennifer C.; Papuga, Shirley A.; Rasmussen, Craig; Schaap, Marcel; Swetnam, Tyson L.; Troch, Peter A.

    2013-06-01

    among vegetation dynamics, pedogenesis, and topographic development affect the "critical zone"—the living filter for Earth's hydrologic, biogeochemical, and rock/sediment cycles. Assessing the importance of such feedbacks, which may be particularly pronounced in water-limited systems, remains a fundamental interdisciplinary challenge. The sky islands of southern Arizona offer an unusually well-defined natural experiment involving such feedbacks because mean annual precipitation varies by a factor of five over distances of approximately 10 km in areas of similar rock type (granite) and tectonic history. Here we compile high-resolution, spatially distributed data for Effective Energy and Mass Transfer (EEMT: the energy available to drive bedrock weathering), above-ground biomass, soil thickness, hillslope-scale topographic relief, and drainage density in two such mountain ranges (Santa Catalina: SCM; Pinaleño: PM). Strong correlations exist among vegetation-soil-topography variables, which vary nonlinearly with elevation, such that warm, dry, low-elevation portions of these ranges are characterized by relatively low above-ground biomass, thin soils, minimal soil organic matter, steep slopes, and high drainage densities; conversely, cooler, wetter, higher elevations have systematically higher biomass, thicker organic-rich soils, gentler slopes, and lower drainage densities. To test if eco-pedo-geomorphic feedbacks drive this pattern, we developed a landscape evolution model that couples pedogenesis and topographic development over geologic time scales, with rates explicitly dependent on vegetation density. The model self-organizes into states similar to those observed in SCM and PM. Our results highlight the potential importance of eco-pedo-geomorphic feedbacks, mediated by soil thickness, in water-limited systems.

  17. Seasonal dynamics and long-term trend of hypoxia in the coastal zone of Emilia Romagna (NW Adriatic Sea, Italy).

    Science.gov (United States)

    Alvisi, Francesca; Cozzi, Stefano

    2016-01-15

    Long-term series of meteorological, hydrological and oceanographic data were compared with hypoxia occurrence, in order to define characteristics and trends of this phenomenon in the Emilia Romagna Coastal Zone (ERCZ) in 1977-2008. During this period, hypoxia was recorded at all sampling stations, up to 20 km offshore. In winter, spring and late autumn, hypoxia appearance was matched to significant positive anomalies of air and surface seawater temperatures (up to +3.6 °C), whereas this effect was less pronounced in August-October. Hypoxia generally occurred with scarce precipitation (0-2 dm(3)m(2)d(-1)) and low wind velocity (0-2 ms(-1)), suggesting the importance of stable meteo-marine conditions for the onset of this phenomenon. Nevertheless, wind direction emerged as an indicator of hydrodynamic seasonal changes in the area and is thus a hypoxia regulator. In winter, spring and autumn, hypoxia was favored by large increases of biomass induced by river freshets. In contrast, summer hypoxia occurred during periods of low runoff, suggesting that pronounced stratification and weak circulation of coastal waters were more important in this season. Since the 1990s, a shift from widespread summer hypoxia to local hypoxia irregularly distributed across the year has occurred. This process was concomitant to long-term increases of air temperature (+0.14 °C yr(-1)), wind speed (+0.03 ms(-1) yr(-1)) and salinity (+0.09 yr(-1)), and decreases of Po River flow (-0.54 km(3) yr(-1)), oxygen saturation (-0.2% yr(-1)) and PO4(3-) (-0.004 μmol P L(-1) yr(-1)) and NH4(+) (-0.04 μmol N L(-1) yr(-1)) concentrations in surface coastal waters. Despite that several of these changes suggest an ERCZ trophic level positive reduction, similar to that reported for the N Adriatic, the concomitant climate warming might further exacerbate hypoxia in particularly shallow shelf locations. Therefore, in order to avoid hypoxia development a further mitigation of anthropogenic pressure is still

  18. Nonthermal physical technologies to decontaminate and extend the shelf-life of fruits and vegetables: Trends aiming at quality and safety.

    Science.gov (United States)

    Pinela, José; Ferreira, Isabel C F R

    2017-07-03

    Minimally processed fruits and vegetables are one of the major growing sectors in food industry. This growing demand for healthy and convenient foods with fresh-like properties is accompanied by concerns surrounding efficacy of the available sanitizing methods to appropriately deal with food-borne diseases. In fact, chemical sanitizers do not provide an efficient microbial reduction, besides being perceived negatively by the consumers, dangerous for human health, and harmful to the environment, and the conventional thermal treatments may negatively affect physical, nutritional, or bioactive properties of these perishable foods. For these reasons, the industry is investigating alternative nonthermal physical technologies, namely innovative packaging systems, ionizing and ultraviolet radiation, pulsed light, high-power ultrasound, cold plasma, high hydrostatic pressure, and dense phase carbon dioxide, as well as possible combinations between them or with other preservation factors (hurdles). This review discusses the potential of these novel or emerging technologies for decontamination and shelf-life extension of fresh and minimally processed fruits and vegetables. Advantages, limitations, and challenges related to its use in this sector are also highlighted.

  19. Towards a more objective evaluation of modelled land-carbon trends using atmospheric CO2 and satellite-based vegetation activity observations

    Directory of Open Access Journals (Sweden)

    D. Dalmonech

    2013-06-01

    Full Text Available Terrestrial ecosystem models used for Earth system modelling show a significant divergence in future patterns of ecosystem processes, in particular the net land–atmosphere carbon exchanges, despite a seemingly common behaviour for the contemporary period. An in-depth evaluation of these models is hence of high importance to better understand the reasons for this disagreement. Here, we develop an extension for existing benchmarking systems by making use of the complementary information contained in the observational records of atmospheric CO2 and remotely sensed vegetation activity to provide a novel set of diagnostics of ecosystem responses to climate variability in the last 30 yr at different temporal and spatial scales. The selection of observational characteristics (traits specifically considers the robustness of information given that the uncertainty of both data and evaluation methodology is largely unknown or difficult to quantify. Based on these considerations, we introduce a baseline benchmark – a minimum test that any model has to pass – to provide a more objective, quantitative evaluation framework. The benchmarking strategy can be used for any land surface model, either driven by observed meteorology or coupled to a climate model. We apply this framework to evaluate the offline version of the MPI Earth System Model's land surface scheme JSBACH. We demonstrate that the complementary use of atmospheric CO2 and satellite-based vegetation activity data allows pinpointing of specific model deficiencies that would not be possible by the sole use of atmospheric CO2 observations.

  20. Identification of long-term trends and seasonality in high-frequency water quality data from the Yangtze River basin, China

    Science.gov (United States)

    He, Bin; Chen, Yaning; Zou, Shan; Wang, Yi; Nover, Daniel; Chen, Wen; Yang, Guishan

    2018-01-01

    Comprehensive understanding of the long-term trends and seasonality of water quality is important for controlling water pollution. This study focuses on spatio-temporal distributions, long-term trends, and seasonality of water quality in the Yangtze River basin using a combination of the seasonal Mann-Kendall test and time-series decomposition. The used weekly water quality data were from 17 environmental stations for the period January 2004 to December 2015. Results show gradual improvement in water quality during this period in the Yangtze River basin and greater improvement in the Uppermost Yangtze River basin. The larger cities, with high GDP and population density, experienced relatively higher pollution levels due to discharge of industrial and household wastewater. There are higher pollution levels in Xiang and Gan River basins, as indicated by higher NH4-N and CODMn concentrations measured at the stations within these basins. Significant trends in water quality were identified for the 2004–2015 period. Operations of the three Gorges Reservoir (TGR) enhanced pH fluctuations and possibly attenuated CODMn, and NH4-N transportation. Finally, seasonal cycles of varying strength were detected for time-series of pollutants in river discharge. Seasonal patterns in pH indicate that maxima appear in winter, and minima in summer, with the opposite true for CODMn. Accurate understanding of long-term trends and seasonality are necessary goals of water quality monitoring system efforts and the analysis methods described here provide essential information for effectively controlling water pollution. PMID:29466354

  1. Identification of long-term trends and seasonality in high-frequency water quality data from the Yangtze River basin, China.

    Science.gov (United States)

    Duan, Weili; He, Bin; Chen, Yaning; Zou, Shan; Wang, Yi; Nover, Daniel; Chen, Wen; Yang, Guishan

    2018-01-01

    Comprehensive understanding of the long-term trends and seasonality of water quality is important for controlling water pollution. This study focuses on spatio-temporal distributions, long-term trends, and seasonality of water quality in the Yangtze River basin using a combination of the seasonal Mann-Kendall test and time-series decomposition. The used weekly water quality data were from 17 environmental stations for the period January 2004 to December 2015. Results show gradual improvement in water quality during this period in the Yangtze River basin and greater improvement in the Uppermost Yangtze River basin. The larger cities, with high GDP and population density, experienced relatively higher pollution levels due to discharge of industrial and household wastewater. There are higher pollution levels in Xiang and Gan River basins, as indicated by higher NH4-N and CODMn concentrations measured at the stations within these basins. Significant trends in water quality were identified for the 2004-2015 period. Operations of the three Gorges Reservoir (TGR) enhanced pH fluctuations and possibly attenuated CODMn, and NH4-N transportation. Finally, seasonal cycles of varying strength were detected for time-series of pollutants in river discharge. Seasonal patterns in pH indicate that maxima appear in winter, and minima in summer, with the opposite true for CODMn. Accurate understanding of long-term trends and seasonality are necessary goals of water quality monitoring system efforts and the analysis methods described here provide essential information for effectively controlling water pollution.

  2. Statistical Analysis of Long-Term Trend of Performance, Production and Cultivated Area of 17 Field Crops Khorasan Razavi Province

    Directory of Open Access Journals (Sweden)

    H. Zareabyaneh

    2014-12-01

    Full Text Available Any planning for the future requires estimates of future conditions. It is possible to study changes over time series. In this study, changes of production and cultivated area of 17 field crops of Khorasan Razavi province in a 25-year period were determined with Mann - Kendall test, Sen’s Estimator Slope and linear regression. Analysis of the three tests showed that performance of 76.5% from yield, 88.2% from area under cultivation and 55.8% from agricultural production were significant at the 0.01 and 0.05 level. On the other hand, trend of yields 58.8% was increase, 17.7% was reduced and 23.5% was no significant trend. Similarly, trend of 23.5% from area under cultivation was acreage, 64.7% was reduction, and 11.8% was no significant trend. For production variable, 29.4% was significantly increased and 29.4% was significant reduction. More detailed analysis showed that performance, production and area under cultivation of three crops of cotton, grain and tomatoes increased significantly. Results of all three methods showed the highest trend of negatively performance and area under cultivation variation is related to pea and melon respectively. Furthermore, most of the positive trend in production of tomatoes and grain, performance in onions, potatoes and tomatoes and area under cultivation in tomato observed. The results showed that linear trend and the nonparametric tests of important products of province: wheat, barley, sugar beet, cotton, melons, watermelons and tomatoes in 0.01 were significant. This result shows the importance of these yields in gross state province product.

  3. Time trend investigation of PCBs, PBDEs, and organochlorine pesticides in selected n-3 polyunsaturated fatty acid rich dietary fish oil and vegetable oil supplements; nutritional relevance for human essential n-3 fatty acid requirements.

    Science.gov (United States)

    Jacobs, Miriam N; Covaci, Adrian; Gheorghe, Adriana; Schepens, Paul

    2004-03-24

    In addition to being used in the food and animal feed industry, fish oils have also been used traditionally as dietary supplements. Due to the presence of long-chain n-3 fatty acids, fish oils have therapeutic benefits in the prevention and treatment of cardiovascular, immunological, and arthritic diseases, as well as childhood deficiency diseases such as rickets, because of a high content of vitamin D. However, fish oils are also susceptible to contamination with lipophilic organic chemicals that are now ubiquitous contaminants of marine ecosystems. Many vegetable oils are sources of the shorter chain precursor forms of n-3 fatty acids, and in recent years the specialist dietary supplement market has expanded to include these oils in a variety of different formulations. This paper reports analytical results of selected contaminants, including polychlorinated biphenyls, organochlorine pesticides, and polybrominated diphenyl ethers, for a range of commercially available n-3 fatty acid rich fish and vegetable oil dietary supplements. Using principal component analysis, the values are compared with historic samples to elucidate time trends in contamination profiles. Levels of contaminants are discussed in relation to the nutritional benefits to the consumer of long- and short-chain forms of n-3 fatty acids.

  4. Comparison of Modeling Grassland Degradation with and without Considering Localized Spatial Associations in Vegetation Changing Patterns

    Directory of Open Access Journals (Sweden)

    Yuwei Wang

    2018-01-01

    Full Text Available Grassland ecosystems worldwide are confronted with degradation. It is of great importance to understand long-term trajectory patterns of grassland vegetation by advanced analytical models. This study proposes a new approach called a binary logistic regression model with neighborhood interactions, or BLR-NIs, which is based on binary logistic regression (BLR, but fully considers the spatio-temporally localized spatial associations or characterization of neighborhood interactions (NIs in the patterns of grassland vegetation. The BLR-NIs model was applied to a modeled vegetation degradation of grasslands in the Xilin river basin, Inner Mongolia, China. Residual trend analysis on the normalized difference vegetation index (RESTREND-NDVI, which excluded the climatic impact on vegetation dynamics, was adopted as a preprocessing step to derive three human-induced trajectory patterns (vegetation degradation, vegetation recovery, and no significant change in vegetation during two consecutive periods, T1 (2000–2008 and T2 (2007–2015. Human activities, including livestock grazing intensity and transportation accessibility measured by road network density, were included as explanatory variables for vegetation degradation, which was defined for locations if vegetation recovery or no significant change in vegetation in T1 and vegetation degradation in T2 were observed. Our work compared the results of BLR-NIs and the traditional BLR model that did not consider NIs. The study showed that: (1 both grazing intensity and road density had a positive correlation to vegetation degradation based on the traditional BLR model; (2 only road density was found to positively correlate to vegetation degradation by the BLR-NIs model; NIs appeared to be critical factors to predict vegetation degradation; and (3 including NIs in the BLR model improved the model performance substantially. The study provided evidence for the importance of including localized spatial

  5. Climate change and coral reef bleaching: An ecological assessment of long-term impacts, recovery trends and future outlook

    Science.gov (United States)

    Baker, Andrew C.; Glynn, Peter W.; Riegl, Bernhard

    2008-12-01

    Since the early 1980s, episodes of coral reef bleaching and mortality, due primarily to climate-induced ocean warming, have occurred almost annually in one or more of the world's tropical or subtropical seas. Bleaching is episodic, with the most severe events typically accompanying coupled ocean-atmosphere phenomena, such as the El Niño-Southern Oscillation (ENSO), which result in sustained regional elevations of ocean temperature. Using this extended dataset (25+ years), we review the short- and long-term ecological impacts of coral bleaching on reef ecosystems, and quantitatively synthesize recovery data worldwide. Bleaching episodes have resulted in catastrophic loss of coral cover in some locations, and have changed coral community structure in many others, with a potentially critical influence on the maintenance of biodiversity in the marine tropics. Bleaching has also set the stage for other declines in reef health, such as increases in coral diseases, the breakdown of reef framework by bioeroders, and the loss of critical habitat for associated reef fishes and other biota. Secondary ecological effects, such as the concentration of predators on remnant surviving coral populations, have also accelerated the pace of decline in some areas. Although bleaching severity and recovery have been variable across all spatial scales, some reefs have experienced relatively rapid recovery from severe bleaching impacts. There has been a significant overall recovery of coral cover in the Indian Ocean, where many reefs were devastated by a single large bleaching event in 1998. In contrast, coral cover on western Atlantic reefs has generally continued to decline in response to multiple smaller bleaching events and a diverse set of chronic secondary stressors. No clear trends are apparent in the eastern Pacific, the central-southern-western Pacific or the Arabian Gulf, where some reefs are recovering and others are not. The majority of survivors and new recruits on

  6. Tropospheric observations of CFC-114 and CFC-114a with a focus on long-term trends and emissions

    Directory of Open Access Journals (Sweden)

    J. C. Laube

    2016-12-01

    Full Text Available Chlorofluorocarbons (CFCs are ozone-depleting substances as well as strong greenhouse gases, and the control of their production and use under the Montreal Protocol has had demonstrable benefits to both mitigation of increasing surface UV radiation and climate forcing. A global ban on consumption came into force in 2010, but there is evidence of continuing emissions of certain CFCs from a range of sources. One compound has received little attention in the literature, namely CFC-114 (C2Cl2F4. Of particular interest here is the differentiation between CFC-114 (CClF2CClF2 and its asymmetric isomeric form CFC-114a (CF3CCl2F as atmospheric long-term measurements in the peer-reviewed literature to date have been assumed to represent the sum of both isomers with a time-invariant isomeric speciation. Here we report the first long-term measurements of the two isomeric forms separately, and find that they have different origins and trends in the atmosphere. Air samples collected at Cape Grim (41° S, Australia, during atmospheric background conditions since 1978, combined with samples collected from deep polar snow (firn enable us to obtain a near-complete record of both gases since their initial production and release in the 1940s. Both isomers were present in the unpolluted atmosphere in comparably small amounts before 1960. The mixing ratio of CFC-114 doubled from 7.9 to 14.8 parts per trillion (ppt between the start of the Cape Grim record in 1978 and the end of our record in 2014, while over the same time CFC-114a trebled from 0.35 to 1.03 ppt. Mixing ratios of both isomers are slowly decreasing by the end of this period. This is consistent with measurements of recent aircraft-based samples showing no significant interhemispheric mixing ratio gradient. We also find that the fraction of CFC-114a mixing ratio relative to that of CFC-114 increased from 4.2 to 6.9 % over the 37-year period. This contradicts the current tacit assumption used in

  7. Tropospheric observations of CFC-114 and CFC-114a with a focus on long-term trends and emissions

    Science.gov (United States)

    Laube, Johannes C.; Hanif, Norfazrin Mohd; Martinerie, Patricia; Gallacher, Eileen; Fraser, Paul J.; Langenfelds, Ray; Brenninkmeijer, Carl A. M.; Schwander, Jakob; Witrant, Emmanuel; Wang, Jia-Lin; Ou-Yang, Chang-Feng; Gooch, Lauren J.; Reeves, Claire E.; Sturges, William T.; Oram, David E.

    2016-12-01

    Chlorofluorocarbons (CFCs) are ozone-depleting substances as well as strong greenhouse gases, and the control of their production and use under the Montreal Protocol has had demonstrable benefits to both mitigation of increasing surface UV radiation and climate forcing. A global ban on consumption came into force in 2010, but there is evidence of continuing emissions of certain CFCs from a range of sources. One compound has received little attention in the literature, namely CFC-114 (C2Cl2F4). Of particular interest here is the differentiation between CFC-114 (CClF2CClF2) and its asymmetric isomeric form CFC-114a (CF3CCl2F) as atmospheric long-term measurements in the peer-reviewed literature to date have been assumed to represent the sum of both isomers with a time-invariant isomeric speciation. Here we report the first long-term measurements of the two isomeric forms separately, and find that they have different origins and trends in the atmosphere. Air samples collected at Cape Grim (41° S), Australia, during atmospheric background conditions since 1978, combined with samples collected from deep polar snow (firn) enable us to obtain a near-complete record of both gases since their initial production and release in the 1940s. Both isomers were present in the unpolluted atmosphere in comparably small amounts before 1960. The mixing ratio of CFC-114 doubled from 7.9 to 14.8 parts per trillion (ppt) between the start of the Cape Grim record in 1978 and the end of our record in 2014, while over the same time CFC-114a trebled from 0.35 to 1.03 ppt. Mixing ratios of both isomers are slowly decreasing by the end of this period. This is consistent with measurements of recent aircraft-based samples showing no significant interhemispheric mixing ratio gradient. We also find that the fraction of CFC-114a mixing ratio relative to that of CFC-114 increased from 4.2 to 6.9 % over the 37-year period. This contradicts the current tacit assumption used in international climate

  8. Publication trends of Allergy, Pediatric Allergy and Immunology, and Clinical and Translational Allergy journals: a MeSH term-based bibliometric analysis.

    Science.gov (United States)

    Martinho-Dias, Daniel; Sousa-Pinto, Bernardo; Botelho-Souza, Júlio; Soares, António; Delgado, Luís; Fonseca, João Almeida

    2018-01-01

    We performed a MeSH term-based bibliometric analysis aiming to assess the publication trends of EAACI journals, namely Allergy, Pediatric Allergy and Immunology (PAI) (from 1990 to 2015) and Clinical and Translational Allergy (CTA) (from its inception in 2011 to 2015). We also aimed to discuss the impact of the creation of CTA in the publication topics of Allergy and PAI. We analysed a total of 1973 articles and 23,660 MeSH terms. Most MeSH terms in the three journals fell in the category of "basic immunology and molecular biology" (BIMB). During the studied period, we observed an increase in the proportion of MeSH terms on BIMB, and a decreasing proportion of terms on allergic rhinitis and aeroallergens. The observed changes in Allergy and PAI publication topics hint at a possible impact from CTA creation.

  9. The U.S. mussel watch : nationwide geographic and long-term trends of PAHs in coastal mussels and oysters

    International Nuclear Information System (INIS)

    Mearns, A.J.; Lauenstein, G.C.; O'Connor, T.P.

    1998-01-01

    The issue of fishery evaluation criteria following oil spills in lakes, rivers and seas was discussed. This paper focused on the problem of developing criteria for closing and opening fisheries during responses to oil spills. Closures are implemented to prevent the public from consuming toxic chemicals such as polycyclic aromatic hydrocarbons (PAHs) and to prevent tainted sea food products from entering the marketplace. A U.S. nationwide program, called Mussel Watch Project of the National Oceanic and Atmospheric Administration (NOAA) National Status and Trends (NS and T) Program, was established to monitor spatial distribution and temporal trends of contaminant concentrations at over 200 coastal and estuarian sites around the U.S. The program has analyzed concentrations of 44 PAHs. The trends of PAHs was compared with other pollutants. An assessment of the extent to which PAHs in mollusks reflect population density was discussed. 16 refs., 4 tabs

  10. Suitability of vegetation for erosion control on uranium mill tailings: a regional analysis

    International Nuclear Information System (INIS)

    Beedlow, P.A.; McShane, M.C.

    1983-11-01

    Inactive uranium mill tailings (UMTRAP sites) in the West were grouped into three major climatic regions to evaluate the adequacy of vegetation for long-term stabilization: the Colorado Plateau, the West Slope of the Rocky Mountains, and the Northern Great Plains. Four general vegetation types were found at western sites: grasslands, shrub-steppe, and saltshrub and woodland. Soil-loss rates, calculated using the Universal Soil Loss Equation, were variable within regions and vegetation types, but trends were apparent. Calculations indicated that vegetation or vegetation plus a layer of surface rock provided adequate stabilization against long-term average soil loss for slopes less than 10% at the UMTRAP sites evaluated. However, detailed analyses of erosion due to severe storm events, gully formation and channel cutting is necessary for designing protective covers at each site. 11 references, 3 figures, 3 tables

  11. The suitability of vegetation for erosion control on uranium mill tailings: A regional analysis

    International Nuclear Information System (INIS)

    Beedlow, P.A.; McShane, M.C.

    1984-01-01

    Inactive uranium mill tailings (UMTRAP sites) in the West were grouped into three major climatic regions to evaluate the suitability of vegetation for long-term stabilization: the Colorado Plateau, the West Slope of the Rocky Mountains, and the Northern Great Plains. Four general vegetation types were found at western sites: grassland, shrub, salt shrub and woodland. Soil-loss rates, calculated using the Universal Soil Loss Equation, were variable within regions and vegetation types, but trends were apparent. Calculations indicated that vegetation or vegetation plus a layer of surface rock provided adequate stabilization against long-term average soil loss on slopes of less than 10%. However, at each site, detailed analyses of erosion caused by severe storm events, gully formation and channel cutting is necessary for designing protective covers

  12. Monitoring temporal Vegetation changes in Lao tropical forests

    International Nuclear Information System (INIS)

    Phompila, Chittana; Lewis, Megan; Clarke, Kenneth; Ostendorf, Bertram

    2014-01-01

    Studies on changes in vegetation are essential for understanding the interaction between humans and the environment. These studies provide key information for land use assessment, terrestrial ecosystem monitoring, carbon flux modelling and impacts of global climate change. The primary purpose of this study was to detect temporal vegetation changes in tropical forests in the southern part of Lao PDR from 2001-2012. The study investigated the annual vegetation phenological response of dominant land cover types across the study area and relationships to seasonal precipitation and temperature. Improved understanding of intra-annual patterns of vegetation variation was useful to detect longer term changes in vegetation. The breaks for additive season and trend (BFAST) approach was implemented to detect changes in these land cover types throughout the 2001-2012 period. We used the enhanced vegetation index (EVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) (MOD13Q1 products) and monthly rainfall and temperature data obtained from the Meteorology and Hydrology Department, Ministry of Agriculture-Forestry, published by Lao National Statistical Centre in this research. EVI well documented the annual seasonal growth of vegetation and clearly distinguished the characteristic phenology of four different land use types; native forest, plantation, agriculture and mixed wooded/cleared area. Native forests maintained high EVI throughout the year, while plantations, wooded/cleared areas and agriculture showed greater inter-annual variation, with minimum EVI at the end of the dry season in April and maximum EVI in September-October, around two months after the wet season peak in rainfall. The BFAST analysis detected abrupt temporal changes in vegetation in the tropical forests, especially in a large conversion of mixed wooded/cleared area into plantation. Within the study area from 2001-2012 there has been an overall decreasing trend of vegetation cover for

  13. Long-term spatiotemporal trends and health risk assessment of oyster arsenic levels in coastal waters of northern South China Sea.

    Science.gov (United States)

    Wang, Xuefeng; Wang, Lifei; Jia, Xiaoping; Jackson, Donald A

    2017-09-01

    Long-term spatiotemporal trends and health risk assessment of oyster arsenic levels in the coastal waters of northern South China Sea were investigated in order to help improve the quality and safety control and sustainable aquaculture for mollusks in China. Cultured oysters (Crassostrea rivularis) collected from the waters of 23 bays, harbors, and estuaries along the coast of northern South China Sea from 1989 to 2012 were examined for spatial patterns and long-term temporal trends of oyster arsenic levels. Single-factor index and health risk assessment were used to quantify arsenic exposure to human health through oyster consumption. Overall, arsenic was detected in 97.4% of the oyster samples, and oyster arsenic levels were non-detectable-2.51 mg/kg with an average of 0.63 ± 0.54 mg/kg. Oyster arsenic levels in the coastal waters of northern South China Sea showed an overall decline from 1989 to 2012, remained relatively low since 2005, and slightly increased after 2007. Oyster arsenic levels in Guangdong coastal waters were much higher with more variation than in Guangxi and Hainan coastal waters, and the long-term trends of oyster arsenic levels in Guangdong coastal waters dominated the overall trends of oyster arsenic levels in the coastal waters of northern South China Sea. Within Guangdong Province, oyster arsenic levels were highest in east Guangdong coastal waters, followed by the Pearl River estuary and west Guangdong coastal waters. Single-factor index ranged between 0.27 and 0.97, and average health risk coefficient was 3.85 × 10 -5 , both suggesting that oyster arsenic levels in northern South China Sea are within the safe range for human consumption. However, long-term attention should be given to seafood market monitoring in China and the risk of arsenic exposure to human health through oyster consumption.

  14. Recovery from chronic and snowmelt acidification: Long-term trends in stream and soil water chemistry at the Hubbard Brook Experimental Forest, New Hampshire, USA

    Science.gov (United States)

    Colin B. Fuss; Charles T. Driscoll; John L. Campbell

    2015-01-01

    Atmospheric acid deposition of sulfate and nitrate has declined markedly in the northeastern United States due to emissions controls. We investigated long-term trends in soil water (1984–2011) and stream water (1982–2011) chemistry along an elevation gradient of a forested watershed to evaluate the progress of recovery of drainage waters from acidic deposition at the...

  15. Evaluating the performance of water purification in a vegetated groundwater recharge basin maintained by short-term pulsed infiltration events.

    Science.gov (United States)

    Mindl, Birgit; Hofer, Julia; Kellermann, Claudia; Stichler, Willibald; Teichmann, Günter; Psenner, Roland; Danielopol, Dan L; Neudorfer, Wolfgang; Griebler, Christian

    2015-01-01

    Infiltration of surface water constitutes an important pillar in artificial groundwater recharge. However, insufficient transformation of organic carbon and nutrients, as well as clogging of sediments often cause major problems. The attenuation efficiency of dissolved organic carbon (DOC), nutrients and pathogens versus the risk of bioclogging for intermittent recharge were studied in an infiltration basin covered with different kinds of macrovegetation. The quality and concentration of organic carbon, major nutrients, as well as bacterial biomass, activity and diversity in the surface water, the porewater, and the sediment matrix were monitored over one recharge period. Additionally, the numbers of viral particles and Escherichia coli were assessed. Our study showed a fast establishment of high microbial activity. DOC and nutrients have sustainably been reduced within 1.2 m of sediment passage. Numbers of E. coli, which were high in the topmost centimetres of sediment porewater, dropped below the detection limit. Reed cover was found to be advantageous over bushes and trees, since it supported higher microbial activities along with a good infiltration and purification performance. Short-term infiltration periods of several days followed by a break of similar time were found suitable for providing high recharge rates, and good water purification without the risk of bioclogging.

  16. LONG-TERM TRENDS IN GROWTH OF PINUS PALUSTRIS AND PINUS ELLIOTTII GROWING ALONG A HYDROLOGICAL GRADIENT IN CENTRAL FLORIDA

    Science.gov (United States)

    Land-use change and urbanization has led to changes in the hydrologic regime in wet central Florida, with a trend toward lowered water table levels. These hydrologic changes are having environmental consequences in wetlands, where shifts in species composition and fire frequency...

  17. Assessment of short- and long-term memory in trends of major climatic variables over Iran: 1966–2015

    NARCIS (Netherlands)

    Mianabadi, Ameneh; Shirazi, Pooya; Ghahraman, Bijan; Coenders, A.M.J.; Alizadeh, Amin; Davary, Kamran

    2018-01-01

    In arid and semi-arid regions, water scarcity is the crucial issue for crop production. Identifying the spatial and temporal trends in aridity, especially during the crop-growing season, is important for farmers to manage their agricultural practices. This will become especially relevant when

  18. The role of birth cohorts in long-term trends in liver cirrhosis mortality across eight European countries

    NARCIS (Netherlands)

    Trias-Llimós, Sergi; Bijlsma, Maarten J; Janssen, Fanny

    BACKGROUND AND AIMS: Understanding why inequalities in alcohol-related mortality trends by sex and country exist, is essential for developing health policies. Birth cohort effects, indicative of differences by generation in drinking, have rarely been studied. This study estimated the relative

  19. The role of birth cohorts in long-term trends in liver cirrhosis mortality across eight European countries.

    NARCIS (Netherlands)

    Trias Llimós, S.; Bijlsma, M.; Janssen, F.

    2017-01-01

    Background and aims Understanding why inequalities in alcohol-related mortality trends by sex and country exist, is essential for developing health policies. Birth cohort effects, indicative of differences by generation in drinking, have rarely been studied. This study estimated the relative

  20. Vegetation cover and long-term conservation of radioactive waste packages: the case study of the CSM waste disposal facility (Manche District, France).

    Science.gov (United States)

    Petit-Berghem, Yves; Lemperiere, Guy

    2012-03-01

    The CSM is the first French waste disposal facility for radioactive waste. Waste material is buried several meters deep and protected by a multi-layer cover, and equipped with a drainage system. On the surface, the plant cover is a grassland vegetation type. A scientific assessment has been carried out by the Géophen laboratory, University of Caen, in order to better characterize the plant cover (ecological groups and associated soils) and to observe its medium and long term evolution. Field assessments made on 10 plots were complemented by laboratory analyses carried out over a period of 1 year. The results indicate scenarios and alternative solutions which could arise, in order to passively ensure the long-term safety of the waste disposal system. Several proposals for a blanket solution are currently being studied and discussed, under the auspices of international research institutions in order to determine the most appropriate materials for the storage conditions. One proposal is an increased thickness of these materials associated with a geotechnical barrier since it is well adapted to the forest plants which are likely to colonize the site. The current experiments that are carried out will allow to select the best option and could provide feedback for other waste disposal facility sites already being operated in France (CSFMA waste disposal facility, Aube district) or in other countries.

  1. Factors affecting long-term trends in surface-water quality in the Gwynns Falls watershed, Baltimore City and County, Maryland, 1998–2016

    Science.gov (United States)

    Majcher, Emily H.; Woytowitz, Ellen L.; Reisinger, Alexander J.; Groffman, Peter M.

    2018-03-30

    Factors affecting water-quality trends in urban streams are not well understood, despite current regulatory requirements and considerable ongoing investments in gray and green infrastructure. To address this gap, long-term water-quality trends and factors affecting these trends were examined in the Gwynns Falls, Maryland, watershed during 1998–2016 in cooperation with Blue Water Baltimore. Data on water-quality constituents and potential factors of influence were obtained from multiple sources and compiled for analysis, with a focus on data collected as part of the National Science Foundation funded Long-Term Ecological Research project, the Baltimore Ecosystem Study.Variability in climate (specifically, precipitation) and land cover can overwhelm actions taken to improve water quality and can present challenges for meeting regulatory goals. Analysis of land cover during 2001–11 in the Gwynns Falls watershed indicated minimal change during the study time frame; therefore, land-cover change is likely not a factor affecting trends in water quality. However, a modest increase in annual precipitation and a significant increase in winter precipitation were apparent in the region. A higher proportion of runoff producing storms was observed in the winter and a lower proportion in the summer, indicating that climate change may affect water quality in the watershed. The increase in precipitation was not reflected in annual or seasonal trends of streamflow in the watershed. Nonetheless, these precipitation changes may exacerbate the inflow and infiltration of water to gray infrastructure and reduce the effectiveness of green infrastructure. For streamflow and most water-quality constituents examined, no discernable trends were noted over the timeframe examined. Despite the increases in precipitation, no trends were observed for annual or seasonal discharge at the various sites within the study area. In some locations, nitrate, phosphate, and total nitrogen show downward

  2. Deterioration trends of asphalt pavement friction and roughness from medium-term surveys on major Italian roads

    Directory of Open Access Journals (Sweden)

    Alberti Susanna

    2017-09-01

    Full Text Available Deterioration models are the key factor for effective Pavement Management Systems, helping out road agencies to assess the actual pavement condition and forecast future performance of the asset. Among pavement condition characteristics, friction should be taken into account due to its important effect on user safety, while roughness could be used to express user comfort. The purpose of this study was to provide a reasonable case study for future improvements of Italian road management, even if the length of the analyzed highways was not intended to be representative of the overall Italian network.This research studied the friction trend (Side Force Coefficient depending on traffic levels (ESALs and pavement aging for Italian highways, combining the data with roughness and macrotexture. Surface characteristics were monitored during a seven-year time span. A selection of different road sections with homogeneous traffic levels, similar environmental conditions and surface material was performed and high-speed/high-quality road surveys were used for distress data collection. Pavement deterioration models for Italian road sectors were developed at project level, as starting point to advance pavement management practices in Italy. Degradation curves showed the same trends for similar pavement structures, materials and traffic levels; on the other hand, differences in pavement characteristics, increased ESALs and various maintenance treatments significantly altered those trends. Keywords: Pavement Management System, Deterioration models, Friction, Roughness, MPD, High-speed monitoring

  3. Differing long term trends for two common amphibian species (Bufo bufo and Rana temporaria in alpine landscapes of Salzburg, Austria.

    Directory of Open Access Journals (Sweden)

    Martin Kyek

    Full Text Available This study focuses on the population trends of two widespread European anuran species: the common toad (Bufo bufo and the common frog (Rana temporaria. The basis of this study is data gathered over two decades of amphibian fencing alongside roads in the Austrian state of Salzburg. Different statistical approaches were used to analyse the data. Overall average increase or decrease of each species was estimated by calculating a simple average locality index. In addition the statistical software TRIM was used to verify these trends as well as to categorize the data based on the geographic location of each migration site. The results show differing overall trends for the two species: the common toad being stable and the common frog showing a substantial decline over the last two decades. Further analyses based on geographic categorization reveal the strongest decrease in the alpine range of the species. Drainage and agricultural intensification are still ongoing problems within alpine areas, not only in Salzburg. Particularly in respect to micro-climate and the availability of spawning places these changes appear to have a greater impact on the habitats of the common frog than the common toad. Therefore we consider habitat destruction to be the main potential reason behind this dramatic decline. We also conclude that the substantial loss of biomass of a widespread species such as the common frog must have a severe, and often overlooked, ecological impact.

  4. Analysis of rainfall and temperature time series to detect long-term climatic trends and variability over semi-arid Botswana

    Science.gov (United States)

    Byakatonda, Jimmy; Parida, B. P.; Kenabatho, Piet K.; Moalafhi, D. B.

    2018-03-01

    Arid and semi-arid environments have been identified with locations prone to impacts of climate variability and change. Investigating long-term trends is one way of tracing climate change impacts. This study investigates variability through annual and seasonal meteorological time series. Possible inhomogeneities and years of intervention are analysed using four absolute homogeneity tests. Trends in the climatic variables were determined using Mann-Kendall and Sen's Slope estimator statistics. Association of El Niño Southern Oscillation (ENSO) with local climate is also investigated through multivariate analysis. Results from the study show that rainfall time series are fully homogeneous with 78.6 and 50% of the stations for maximum and minimum temperature, respectively, showing homogeneity. Trends also indicate a general decrease of 5.8, 7.4 and 18.1% in annual, summer and winter rainfall, respectively. Warming trends are observed in annual and winter temperature at 0.3 and 1.5% for maximum temperature and 1.7 and 6.5% for minimum temperature, respectively. Rainfall reported a positive correlation with Southern Oscillation Index (SOI) and at the same time negative association with Sea Surface Temperatures (SSTs). Strong relationships between SSTs and maximum temperature are observed during the El Niño and La Niña years. These study findings could facilitate planning and management of agricultural and water resources in Botswana.

  5. Analysis of long-term trends (1950–2009) in precipitation, runoff and runoff coefficient in major urban watersheds in the United States

    International Nuclear Information System (INIS)

    Velpuri, N M; Senay, G B

    2013-01-01

    This study investigates the long-term trends in precipitation, runoff and runoff coefficient in major urban watersheds in the United States. The seasonal Mann–Kendall trend test was performed on monthly precipitation, runoff and runoff coefficient data from 1950 to 2009 obtained from 62 urban watersheds covering 21 major urban centers in the United States. The results indicate that only five out of 21 urban centers in the United States showed an uptrend in precipitation. Twelve urban centers showed an uptrend in runoff coefficient. However, six urban centers did not show any trend in runoff coefficient, and three urban centers showed a significant downtrend. The highest rate of change in precipitation, runoff and runoff coefficient was observed in the Houston urban watershed. Based on the results obtained, we also attributed plausible causes for the trends. Our analysis indicated that while a human only influence is observed in most of the urban watersheds, a combined climate and human influence is observed in the central United States. (letter)

  6. Long-term (2001-2012) trends of carbonaceous aerosols from a remote island in the western North Pacific: an outflow region of Asian pollutants

    Science.gov (United States)

    Boreddy, Suresh K. R.; Mozammel Haque, M.; Kawamura, Kimitaka

    2018-01-01

    The present study reports on long-term trends of carbonaceous aerosols in total suspended particulate (TSP) samples collected at Chichijima in the western North Pacific during 2001-2012. Seasonal variations of elemental carbon (EC), organic carbon (OC), and water-soluble organic carbon (WSOC) concentrations showed maxima in winter to spring and minima in summer. These seasonal differences in the concentrations of carbonaceous aerosols were associated with the outflows of polluted air masses from East Asia, which are clearly distinguishable from pristine air masses from the central Pacific. The higher concentrations of carbonaceous aerosols during winter to spring are associated with long-range atmospheric transport of East Asian continental polluted air masses, whereas lower concentrations may be due to pristine air masses from the central Pacific in summer. The annual trends of OC / EC (+0.46 % yr-1), WSOC (+0.18 % yr-1) and WSOC / OC (+0.08 % yr-1) showed significant (p Asia.

  7. Long-term trends at the Boknis Eck time series station (Baltic Sea, 1957–2013: does climate change counteract the decline in eutrophication?

    Directory of Open Access Journals (Sweden)

    S. T. Lennartz

    2014-11-01

    Full Text Available The Boknis Eck (BE time series station, initiated in 1957, is one of the longest-operated time series stations worldwide. We present the first statistical evaluation of a data set of nine physical, chemical and biological parameters in the period of 1957–2013. In the past three to five decades, all of the measured parameters underwent significant long-term changes. Most striking is an ongoing decline in bottom water oxygen concentration, despite a significant decrease of nutrient and chlorophyll a concentrations. Temperature-enhanced oxygen consumption in the bottom water and a prolongation of the stratification period are discussed as possible reasons for the ongoing oxygen decline despite declining eutrophication. Observations at the BE station were compared with model output of the Kiel Baltic Sea Ice Ocean Model (BSIOM. Reproduced trends were in good agreement with observed trends for temperature and oxygen, but generally the oxygen concentration at the bottom has been overestimated.

  8. Remotely Sensed Northern Vegetation Response to Changing Climate: Growing Season and Productivity Perspective

    Science.gov (United States)

    Ganguly, S.; Park, Taejin; Choi, Sungho; Bi, Jian; Knyazikhin, Yuri; Myneni, Ranga

    2016-01-01

    Vegetation growing season and maximum photosynthetic state determine spatiotemporal variability of seasonal total gross primary productivity of vegetation. Recent warming induced impacts accelerate shifts on growing season and physiological status over Northern vegetated land. Thus, understanding and quantifying these changes are very important. Here, we first investigate how vegetation growing season and maximum photosynthesis state are evolved and how such components contribute on inter-annual variation of seasonal total gross primary productivity. Furthermore, seasonally different response of northern vegetation to changing temperature and water availability is also investigated. We utilized both long-term remotely sensed data to extract larger scale growing season metrics (growing season start, end and duration) and productivity (i.e., growing season summed vegetation index, GSSVI) for answering these questions. We find that regionally diverged growing season shift and maximum photosynthetic state contribute differently characterized productivity inter-annual variability and trend. Also seasonally different response of vegetation gives different view of spatially varying interaction between vegetation and climate. These results highlight spatially and temporally varying vegetation dynamics and are reflective of biome-specific responses of northern vegetation to changing climate.

  9. Evaluation of long-term trends in hydrologic and water-quality conditions, and estimation of water budgets through 2013, Chester County, Pennsylvania

    Science.gov (United States)

    Sloto, Ronald A.; Reif, Andrew G.

    2017-06-02

    An evaluation of trends in hydrologic and water quality conditions and estimation of water budgets through 2013 was done by the U.S. Geological Survey in cooperation with the Chester County Water Resources Authority. Long-term hydrologic, meteorologic, and biologic data collected in Chester County, Pennsylvania, which included streamflow, groundwater levels, surface-water quality, biotic integrity, precipitation, and air temperature were analyzed to determine possible trends or changes in hydrologic conditions. Statistically significant trends were determined by applying the Kendall rank correlation test; the magnitudes of the trends were determined using the Sen slope estimator. Water budgets for eight selected watersheds were updated and a new water budget was developed for the Marsh Creek watershed. An average water budget for Chester County was developed using the eight selected watersheds and the new Marsh Creek water budget.Annual and monthly mean streamflow, base flow, and runoff were analyzed for trends at 10 streamgages. The periods of record at the 10 streamgages ranged from 1961‒2013 to 1988‒2013. The only statistically significant trend for annual mean streamflow was for West Branch Brandywine Creek near Honey Brook, Pa. (01480300) where annual mean streamflow increased 1.6 cubic feet per second (ft3/s) per decade. The greatest increase in monthly mean streamflow was for Brandywine Creek at Chadds Ford, Pa. (01481000) for December; the increase was 47 ft3/s per decade. No statistically significant trends in annual mean base flow or runoff were determined for the 10 streamgages. The greatest increase in monthly mean base flow was for Brandywine Creek at Chadds Ford, Pa. (01481000) for December; the increase was 26 ft3/s per decade.The magnitude of peaks greater than a base streamflow was analyzed for trends for 12 streamgages. The period of record at the 12 stream gages ranged from 1912‒2012 to 2004–11. Fifty percent of the streamgages showed a

  10. Long-term temperature trends and variability on Spitsbergen: the extended Svalbard Airport temperature series, 1898–2012

    Directory of Open Access Journals (Sweden)

    Øyvind Nordli

    2014-01-01

    Full Text Available One of the few long instrumental records available for the Arctic is the Svalbard Airport composite series that hitherto began in 1911, with observations made on Spitsbergen, the largest island in the Svalbard Archipelago. This record has now been extended to 1898 with the inclusion of observations made by hunting and scientific expeditions. Temperature has been observed almost continuously in Svalbard since 1898, although at different sites. It has therefore been possible to create one composite series for Svalbard Airport covering the period 1898–2012, and this valuable new record is presented here. The series reveals large temperature variability on Spitsbergen, with the early 20th century warming as one striking feature: an abrupt change from the cold 1910s to the local maxima of the 1930s and 1950s. With the inclusion of the new data it is possible to show that the 1910s were colder than the years at the start of the series. From the 1960s, temperatures have increased, so the present temperature level is significantly higher than at any earlier period in the instrumental history. For the entire period, and for all seasons, there are positive, statistically significant trends. Regarding the annual mean, the total trend is 2.6°C/century, whereas the largest trend is in spring, at 3.9°C/century. In Europe, it is the Svalbard Archipelago that has experienced the greatest temperature increase during the latest three decades. The composite series may be downloaded from the home page of the Norwegian Meteorological Institute and should be used with reference to the present article.

  11. Trend Change Detection in NDVI Time Series: Effects of Inter-Annual Variability and Methodology

    Science.gov (United States)

    Forkel, Matthias; Carvalhais, Nuno; Verbesselt, Jan; Mahecha, Miguel D.; Neigh, Christopher S.R.; Reichstein, Markus

    2013-01-01

    Changing trends in ecosystem productivity can be quantified using satellite observations of Normalized Difference Vegetation Index (NDVI). However, the estimation of trends from NDVI time series differs substantially depending on analyzed satellite dataset, the corresponding spatiotemporal resolution, and the applied statistical method. Here we compare the performance of a wide range of trend estimation methods and demonstrate that performance decreases with increasing inter-annual variability in the NDVI time series. Trend slope estimates based on annual aggregated time series or based on a seasonal-trend model show better performances than methods that remove the seasonal cycle of the time series. A breakpoint detection analysis reveals that an overestimation of breakpoints in NDVI trends can result in wrong or even opposite trend estimates. Based on our results, we give practical recommendations for the application of trend methods on long-term NDVI time series. Particularly, we apply and compare different methods on NDVI time series in Alaska, where both greening and browning trends have been previously observed. Here, the multi-method uncertainty of NDVI trends is quantified through the application of the different trend estimation methods. Our results indicate that greening NDVI trends in Alaska are more spatially and temporally prevalent than browning trends. We also show that detected breakpoints in NDVI trends tend to coincide with large fires. Overall, our analyses demonstrate that seasonal trend methods need to be improved against inter-annual variability to quantify changing trends in ecosystem productivity with higher accuracy.

  12. Decreasing soil water Ca2+ reduces DOC adsorption in mineral soils: implications for long-term DOC trends in an upland forested catchment in southern Ontario, Canada.

    Science.gov (United States)

    Kerr, Jason Grainger; Eimers, M Catherine

    2012-06-15

    Positive trends in dissolved organic carbon (DOC) concentration have been observed in surface waters throughout North America and northern Europe. Although adsorption in mineral soils is an important driver of DOC in upland streams, little is known about the potential for changes in DOC adsorption to contribute to these trends. We hypothesized that long-term declines in soil water Ca(2+) levels, in response to declining acid deposition, might influence DOC adsorption and that this could contribute to long-term DOC trends in an upland forested catchment in south-central Ontario, Canada. Between 1987 and 2009, DOC concentrations increased significantly (pDOC concentration (DOC(np)), which is a measure of the soil water DOC concentration at equilibrium with the soil, ranged from 1.27 to 3.75 mg L(-1) in B horizon soils. This was similar to the mean DOC concentrations of B horizon soil water (2.04-6.30 mg L(-1)) and stream water (2.20 mg L(-1)), indicating that soil and stream water DOC concentrations are controlled by equilibrium processes at the soil-water interface. Adsorption experiments using variable Ca(2+) concentrations demonstrated that as Ca(2+) decreased the DOC(np) increased (1.96 to 4.74 mg L(-1)), which was consistent with the observed negative correlation between DOC and Ca(2+) in B horizon soil water (pDOC adsorption (p>0.05), indicating that changes in DOC adsorption might be related to cation bridging. We conclude that declines in soil water Ca(2+) concentration can contribute to increasing DOC trends in upland streams by reducing DOC adsorption in mineral soils. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Risk Assessment of Heavy Metal Contamination on Vegetables Grown in Long-term Wastewater Irrigated Urban Farming Sites in Accra, Ghana

    DEFF Research Database (Denmark)

    Lente, I.; Keraita, Bernard; Drechsel, P.

    2012-01-01

    Assessment was done of heavy-metal contamination and its related health risks in urban vegetable farming in Accra. Samples of irrigation water (n = 120), soil (n = 144) and five different kinds of vegetable (n = 240) were collected and analyzed for copper, zinc, lead, cadmium, chromium, nickel an...

  14. Surface-Water Quality Conditions and Long-Term Trends at Selected Sites within the Ambient Water-Quality Monitoring Network in Missouri, Water Years 1993-2008

    Science.gov (United States)

    Barr, Miya N.; Davis, Jerri V.

    2010-01-01

    The U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, collects data pertaining to the surface-water resources of Missouri. These data are collected as part of the Missouri Ambient Water-Quality Monitoring Network and constitute a valuable source of reliable, impartial, and timely information for developing an improved understanding of water resources in the State. Six sites from the Ambient Water-Quality Monitoring Network, with data available from the 1993 through 2008 water years, were chosen to compare water-quality conditions and long-term trends of dissolved oxygen, selected physical properties, total suspended solids, dissolved nitrate plus nitrite as nitrogen, total phosphorous, fecal indicator bacteria, and selected trace elements. The six sites used in the study were classified in groups corresponding to the physiography, main land use, and drainage basin size, and represent most stream types in Missouri. Long-term trends in this study were analyzed using flow-adjusted and non-flow adjusted models. Highly censored datasets (greater than 5 percent but less than 50 percent censored values) were not flow-adjusted. Trends that were detected can possibly be related to changes in agriculture or urban development within the drainage basins. Trends in nutrients were the most prevalent. Upward flow-adjusted trends in dissolved nitrate plus nitrite (as nitrogen) concentrations were identified at the Elk River site, and in total phosphorus concentrations at the South Fabius and Grand River sites. A downward flow-adjusted trend was identified in total phosphorus concentrations from Wilson Creek, the only urban site in the study. The downward trend in phosphorus possibly was related to a phosphorus reduction system that began operation in 2001 at a wastewater treatment plant upstream from the sampling site. Total suspended solids concentrations indicated an upward non-flow adjusted trend at the two northern sites (South Fabius

  15. Satellite view of seasonal greenness trends and controls in South Asia

    Science.gov (United States)

    Sarmah, Sangeeta; Jia, Gensuo; Zhang, Anzhi

    2018-03-01

    South Asia (SA) has been considered one of the most remarkable regions for changing vegetation greenness, accompanying its major expansion of agricultural activities, especially irrigated farming. The influence of the monsoon climate on the seasonal trends and anomalies of vegetation greenness is poorly understood in this area. Herein, we used the satellite-based Normalized Difference Vegetation Index (NDVI) to investigate various spatiotemporal patterns in vegetation activity during summer and winter monsoon (SM and WM) seasons and among irrigated croplands (IC), rainfed croplands (RC), and natural vegetation (NV) areas during 1982–2013. Seasonal NDVI variations with climatic factors (precipitation and temperature) and land use and cover changes (LUCC) have also been investigated. This study demonstrates that the seasonal dynamics of vegetation could improve the detailed understanding of vegetation productivity over the region. We found distinct greenness trends between two monsoon seasons and among the major land use/cover classes. Winter monsoons contributed greater variability to the overall vegetation dynamics of SA. Major greening occurred due to the increased productivity over irrigated croplands during the winter monsoon season; meanwhile, browning trends were prominent over NV areas during the same season. Maximum temperatures had been increasing tremendously during the WM season; however, the precipitation trend was not significant over SA. Both the climate variability and LUCC revealed coupled effects on the long term NDVI trends in NV areas, especially in the hilly regions, whereas anthropogenic activities (agricultural advancements) played a pivotal role in the rest of the area. Until now, advanced cultivation techniques have proven to be beneficial for the region in terms of the productivity of croplands. However, the crop productivity is at risk under climate change.

  16. Providing long-term trend and gravimetric factor at Chandler period from superconducting gravimeter records by using Singular Spectrum Analysis along with its multivariate extension

    Science.gov (United States)

    Gruszczynska, M.; Rosat, S.; Klos, A.; Bogusz, J.

    2017-12-01

    In this study, Singular Spectrum Analysis (SSA) along with its multivariate extension MSSA (Multichannel SSA) were used to estimate long-term trend and gravimetric factor at the Chandler wobble frequency from superconducting gravimeter (SG) records. We have used data from seven stations located worldwide and contributing to the International Geodynamics and Earth Tides Service (IGETS). The timespan ranged from 15 to 19 years. Before applying SSA and MSSA, we had removed local tides, atmospheric (ECMWF data), hydrological (MERRA2 products) loadings and non-tidal ocean loading (ECCO2 products) effects. In the first part of analysis, we used the SSA approach in order to estimate the long-term trends from SG observations. We use the technique based on the classical Karhunen-Loève spectral decomposition of time series into long-term trend, oscillations and noise. In the second part, we present the determination of common time-varying pole tide (annual and Chandler wobble) to estimate gravimetric factor from SG time series using the MSSA approach. The presented method takes advantage over traditional methods like Least Squares Estimation by determining common modes of variability which reflect common geophysical field. We adopted a 6-year lag-window as the optimal length to extract common seasonal signals and the Chandler components of the Earth polar motion. The signals characterized by annual and Chandler wobble account for approximately 62% of the total variance of residual SG data. Then, we estimated the amplitude factors and phase lags of Chandler wobble with respect to the IERS (International Earth Rotation and Reference Systems Service) polar motion observations. The resulting gravimetric factors at the Chandler Wobble period are finally compared with previously estimates. A robust estimate of the gravimetric Earth response to the Chandlerian component of the polar motion is required to better constrain the mantle anelasticity at this frequency and hence the

  17. Development of a Long-term Sampling Network to Monitor Restoration Success in the Southwest Coastal Everglades: Vegetation, Hydrology, and Sediments

    Science.gov (United States)

    Smith, Thomas J.

    2004-01-01

    Introduction and History Hurricane Andrew, a Category 5 storm, crossed the southern Florida peninsula on the morning of August 24, 1992 (Fig. 1). Following the storm, the National Park Service conducted an environmental damage assessment to gauge the storm's impacts on the natural resources of south Florida Park Service holdings (Pimm et al., 1994). Although hurricanes have impacted Park Service lands such as the Everglades in the past (Houston and Powell, 2003), no systematic, permanent sampling scheme has been established to monitor long-term recovery (or lack thereof) following disturbance. In October 1992, vegetation monitoring plots were established in heavily damaged areas of mangrove forest on the southwest coast of the Everlgades, along the Lostmans and Broad Rivers (Smith et al., 1994, see Fig. 2). As the permanent plot network was being established, funding was awarded for the South Florida Global Climate Change project (SOFL-GCC). This led to the establishment of a network of hydrological monitoring stations (Anderson and Smith, 2004). Finally, sediment elevation tables (SETs) were installed at many locations. SETs provide the means to measure very small changes (2 mm) in the sediment surface elevation accurately over time (Cahoon et al., 2002). We also set up marker horizons to measure accretion of sediment at each site (Smith and Cahoon, 2003). Sampling sites were located along three transects extending from upstream freshwater wetlands to downstream saltwater wetlands along the Shark, Lostmans and Chatham Rivers in Everglades National Park (Fig. 2). While we were developing our sampling network for basic scientific research needs, concern mounted over the health of the Greater Everglades Ecosystem and in particular over the influence of decreased freshwater flows (Smith et al., 1989). Ecosystem restoration planning was begun, resulting in the multi-agency, $8 billion Comprehensive Everglades Restoration Plan (CERP). Our co-located sampling networks

  18. Melting of major Glaciers in the western Himalayas: evidence of climatic changes from long term MSU derived tropospheric temperature trend (1979–2008

    Directory of Open Access Journals (Sweden)

    A. K. Prasad

    2009-12-01

    Full Text Available Global warming or the increase of the surface and atmospheric temperatures of the Earth, is increasingly discernible in the polar, sub-polar and major land glacial areas. The Himalayan and Tibetan Plateau Glaciers, which are the largest glaciers outside of the Polar Regions, are showing a large-scale decrease of snow cover and an extensive glacial retreat. These glaciers such as Siachen and Gangotri are a major water resource for Asia as they feed major rivers such as the Indus, Ganga and Brahmaputra. Due to scarcity of ground measuring stations, the long-term observations of atmospheric temperatures acquired from the Microwave Sounding Unit (MSU since 1979–2008 is highly useful. The lower and middle tropospheric temperature trend based on 30 years of MSU data shows warming of the Northern Hemisphere's mid-latitude regions. The mean month-to-month warming (up to 0.048±0.026°K/year or 1.44°K over 30 years of the mid troposphere (near surface over the high altitude Himalayas and Tibetan Plateau is prominent and statistically significant at a 95% confidence interval. Though the mean annual warming trend over the Himalayas (0.016±0.005°K/year, and Tibetan Plateau (0.008±0.006°K/year is positive, the month to month warming trend is higher (by 2–3 times, positive and significant only over a period of six months (December to May. The factors responsible for the reversal of this trend from June to November are discussed here. The inequality in the magnitude of the warming trends of the troposphere between the western and eastern Himalayas and the IG (Indo-Gangetic plains is attributed to the differences in increased aerosol loading (due to dust storms over these regions. The monthly mean lower-tropospheric MSU-derived temperature trend over the IG plains (dust sink region; up to 0.032±0.027°K/year and dust source regions (Sahara desert, Middle East, Arabian region, Afghanistan-Iran-Pakistan and Thar Desert regions; up to 0.068±0.033

  19. The road to success. Long-term prognosis for persons living with HIV in Denmark - time trends and risk factors

    DEFF Research Database (Denmark)

    Lohse, Nicolai

    2016-01-01

    compared temporal trends in quality and quantity of ART introduction in Den-mark and Greenland. Despite similar levels of health worker education and economic resources, ART implementation and mortality decline in Greenland lacked several years behind Denmark. The study reminded us that although economy...... another 39 years, only 12.2 years less than a person in a matched general population cohort would survive. With improved survival and declining HIV-related co-morbidity, non-HIV related co-morbidity became a more visible contributor to the health status of persons with HIV. We assessed the impact of non......-HIV related comorbidity acquired before the person became infected with HIV. We found that 32% of the observed mortality in our cohort was due to HCV and co-morbidities measured by the Charlson Comorbidity Index, 13% corresponded to the background mortality in the population, and that only 55...

  20. A burn prevention program as a long-term investment: trends in burn injuries among Jews and Bedouin children in Israel.

    Science.gov (United States)

    Shani, E; Bahar-Fuchs, S A; Abu-Hammad, I; Friger, M; Rosenberg, L

    2000-03-01

    In order to broaden our long-term intervention efforts in elementary schools in Israel (underway since 1988) and to set priorities for further population-specific actions, we compared the pattern of burn injuries among two age groups (0-4; 5-14) of two ethnic groups of Jews and Bedouins admitted to a regional hospital between 1986 and 1995 (n = 1050). The findings indicated a significant downward trend, though somewhat nonlinear, in burn admissions among the older age groups. A relatively less favorable trend was observed for the younger age groups. Consistently across years, burn rates in the younger group of Bedouin children were the highest. For the 10-year period, a significant season by ethnic group variation in burn admissions was observed, with a peak in the spring and in the wintertime for the Jews and Bedouins, respectively. A significant trend of decrease, mostly among older children, in average lengths of hospital stay, was also evident. Yet, regardless of age group and across years, Bedouin children stayed longer in the hospital than Jewish children. The overall leading causes of injury (for 1992-1995) were hot liquids (69%), fire (17%), chemicals (9.5%) and contact (2%). In our view, there is a need to address at-risk populations through environmental, community and family-oriented interventions and to venture beyond the pathogenic factors to the investigation of the salutary factors of health under diverse life conditions.

  1. The role of diet on long-term concentration and pattern trends of brominated and chlorinated contaminants in western Hudson Bay polar bears, 1991-2007

    International Nuclear Information System (INIS)

    McKinney, Melissa A.; Stirling, Ian; Lunn, Nick J.; Peacock, Elizabeth; Letcher, Robert J.

    2010-01-01

    Adipose tissue was sampled from the western Hudson Bay (WHB) subpopulation of polar bears at intervals from 1991 to 2007 to examine temporal trends of PCB and OCP levels both on an individual and sum-(Σ-)contaminant basis. We also determined levels and temporal trends of emerging polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), polybrominated biphenyls (PBBs) and other current-use brominated flame retardants. Over the 17-year period, Σ DDT (and p,p'-DDE, p,p'-DDD, p,p'-DDT) decreased (-8.4%/year); α-hexachlorocyclohexane (α-HCH) decreased (-11%/year); β-HCH increased (+ 8.3%/year); and Σ PCB and Σ chlordane (CHL), both contaminants at highest concentrations in all years (> 1 ppm), showed no distinct trends even when compared to previous data for this subpopulation dating back to 1968. Some of the less persistent PCB congeners decreased significantly (-1.6%/year to -6.3%/year), whereas CB153 levels tended to increase (+ 3.3%/year). Parent CHLs (c-nonachlor, t-nonachlor) declined, whereas non-monotonic trends were detected for metabolites (heptachlor epoxide, oxychlordane). Σ chlorobenzene, octachlorostyrene, Σ mirex, Σ MeSO 2 -PCB and dieldrin did not significantly change. Increasing Σ PBDE levels (+ 13%/year) matched increases in the four consistently detected congeners, BDE47, BDE99, BDE100 and BDE153. Although no trend was observed, total-(α)-HBCD was only detected post-2000. Levels of the highest concentration brominated contaminant, BB153, showed no temporal change. As long-term ecosystem changes affecting contaminant levels may also affect contaminant patterns, we examined the influence of year (i.e., aging or 'weathering' of the contaminant pattern), dietary tracers (carbon stable isotope ratios, fatty acid patterns) and biological (age/sex) group on congener/metabolite profiles. Patterns of PCBs, CHLs and PBDEs were correlated with dietary tracers and biological group, but only PCB and CHL patterns were correlated with year

  2. Use of Long-Term Opportunistic Surveys to Estimate Trends in Abundance of Hibernating Townsend's Big-Eared Bats

    Science.gov (United States)

    Theodore J. Weller; Shawn C. Thomas; James A. Baldwin

    2014-01-01

    The advent of broad-scale threats to bats such as white-nose syndrome and climate change highlights the need for reliable baseline assessment of their populations. However, few long-term, rigorously designed assessments of bat populations exist, particularly in western North America. Consequently, results of informal monitoring efforts are often the only data available...

  3. A decade of monitoring at Swiss Long-Term Forest Ecosystem Research (LWF) sites: can we observe trends in atmospheric acid deposition and in soil solution acidity?

    Science.gov (United States)

    Pannatier, Elisabeth Graf; Thimonier, Anne; Schmitt, Maria; Walthert, Lorenz; Waldner, Peter

    2011-03-01

    Trends in atmospheric acid deposition and in soil solution acidity from 1995 or later until 2007 were investigated at several forest sites throughout Switzerland to assess the effects of air pollution abatements on deposition and the response of the soil solution chemistry. Deposition of the major elements was estimated from throughfall and bulk deposition measurements at nine sites of the Swiss Long-Term Forest Ecosystem Research network (LWF) since 1995 or later. Soil solution was measured at seven plots at four soil depths since 1998 or later. Trends in the molar ratio of base cations to aluminum (BC/Al) in soil solutions and in concentrations and fluxes of inorganic N (NO(3)-N + NH(4)-N), sulfate (SO(4)-S), and base cations (BC) were used to detect changes in soil solution chemistry. Acid deposition significantly decreased at three out of the nine study sites due to a decrease in total N deposition. Total SO(4)-S deposition decreased at the nine sites, but due to the relatively low amount of SO(4)-S load compared to N deposition, it did not contribute to decrease acid deposition significantly. No trend in total BC deposition was detected. In the soil solution, no trend in concentrations and fluxes of BC, SO(4)-S, and inorganic N were found at most soil depths at five out of the seven sites. This suggests that the soil solution reacted very little to the changes in atmospheric deposition. A stronger reduction in base cations compared to aluminum was detected at two sites, which might indicate that acidification of the soil solution was proceeding faster at these sites.

  4. Spatial and temporal evaluation of long term trend (2005-2014) of OMI retrieved NO2 and SO2 concentrations in Henan Province, China

    Science.gov (United States)

    Zhang, Leishi; Lee, Chih Sheng; Zhang, Ruiqin; Chen, Liangfu

    2017-04-01

    Tropospheric NO2 and SO2 concentrations are of great importance with regard to air quality, atmospheric chemistry, and climate change. Due to lack of surface monitoring stations, this study analyzes long term trend of NO2 and SO2 levels (2005-2014), retrieved from Ozone Monitoring Instrument (OMI) board on the NASA's Aura satellite, in an important region of China - Henan Province. Henan Province, located in North China Plain, has encountered serious air pollution problems including extremely high PM2.5 concentrations and as one of the most polluted region in China. The satellite spatial images clearly show that high levels of both NO2 and SO2 are concentrated in north and northeastern regions with much lower levels observed in other parts of Henan. Both pollutants exhibit the highest levels in winter with the least in summer/spring. The temporal trend analysis based on moving average of deseasonalized and decyclic data indicates that for NO2, there is a continuous increasing pattern from 2005 to 2011 at 6.4% per year, thereafter, it shows a decreasing trend (10.6% per year). As for SO2, the increasing trend is about 16% per year from 2005 to 2007 with decreasing rate 7% per year from 2007 to 2014. The economic development with incredible annual 11% GDP growth in Henan is responsible for increasing levels of NO2 and SO2. The observed decreasing SO2 level starting in 2007 is due to reduced SO2 emission, utilization of flue gas desulfurization (FGD) devices and to some extent, in preparation of Beijing 2008 Olympic Games. On the other hand, increasing vehicle numbers (155% from 2006 to 2012) and coal consumption (37% during the same span), along with the lack of denitration process for removing flue/exhaust gas NOx are responsible for increasing NO2 trend until 2011. The ratio of SO2/NO2 started decreasing in 2007 and dropped significantly from 2011 to 2013 indicating good performance of FGD and ever increasing NOx contribution from mobile sources. Unlike those

  5. Long-term decrease in satellite vegetation indices in response to environmental variables in an iconic desert riparian ecosystem: the Upper San Pedro, Arizona, United States

    Science.gov (United States)

    Nguyen, Uyen; Glenn, Edward P.; Nagler, Pamela L.; Scott, Russell L.

    2015-01-01

    The Upper San Pedro River is one of the few remaining undammed rivers that maintain a vibrant riparian ecosystem in the southwest United States. However, its riparian forest is threatened by diminishing groundwater and surface water inputs, due to either changes in watershed characteristics such as changes in riparian and upland vegetation, or human activities such as regional groundwater pumping. We used satellite vegetation indices to quantify the green leaf density of the groundwater-dependent riparian forest from 1984 to 2012. The river was divided into a southern, upstream (mainly perennial flow) reach and a northern, downstream (mainly intermittent and ephemeral flow) reach. Pre-monsoon (June) Landsat normalized difference vegetation index (NDVI) values showed a 20% drop for the northern reach (P  0·05). NDVI and enhanced vegetation index values were positively correlated (P deterioration of the riparian forest in the northern reach.

  6. RepoTREND. The program package for the integrated long term safety analysis of final repository systems. Version 4.5 (State March 2016); RepoTREND. Das Programmpaket zur integrierten Langzeitsicherheitsanalyse von Endlagersystemen. Version 4.5 (Stand Maerz 2016)

    Energy Technology Data Exchange (ETDEWEB)

    Reiche, Tatiana

    2016-04-15

    The long-term safety analysis is the analysis of final repository behavior after closure includes the spreading of pollutants into the biosphere (mobilization and release of pollutants into the near field, radionuclide migration through the geosphere, radiation exposure in the biosphere) and the radiological consequences. The report describes the program package RepoTREND, the respective modules (near field, GeoTREND, BioTREND and probabilistic analyses), sequencing and postprocessing and the quality management.

  7. Evaluation of Seismic Response Trends from Long-Term Monitoring of Two Instrumented RC Buildings Including Soil-Structure Interaction

    Directory of Open Access Journals (Sweden)

    Faheem Butt

    2012-01-01

    Full Text Available This paper presents analyses of the seismic responses of two reinforced concrete buildings monitored for a period of more than two years. One of the structures was a three-storey reinforced concrete (RC frame building with a shear core, while the other was a three-storey RC frame building without a core. Both buildings are part of the same large complex but are seismically separated from the rest of it. Statistical analysis of the relationships between maximum free field accelerations and responses at different points on the buildings was conducted and demonstrated strong correlation between those. System identification studies using recorded accelerations were undertaken and revealed that natural frequencies and damping ratios of the building structures vary during different earthquake excitations. This variation was statistically examined and relationships between identified natural frequencies and damping ratios, and the peak response acceleration at the roof level were developed. A general trend of decreasing modal frequencies and increasing damping ratios was observed with increased level of shaking and response. Moreover, the influence of soil structure interaction (SSI on the modal characteristics was evaluated. SSI effects decreased the modal frequencies and increased some of the damping ratios.

  8. Long-term trends in mercury and PCB congener concentrations in gannet (Morus bassanus) eggs in Britain

    International Nuclear Information System (INIS)

    Pereira, M. Gloria; Walker, Lee A.; Best, Jennifer; Shore, Richard F.

    2009-01-01

    Gannet (Morus bassanus) eggs from Bass Rock (North Sea) and Ailsa Craig (eastern Atlantic) were monitored for PCB congeners (1990-2004) and total mercury (1974-2004). Congener profiles for both colonies were dominated by PCBs 153, 138, 180, 118 and 170. All declined in concentration at Ailsa Craig but some (153, 170, 180) remained stable or increased slightly at Bass Rock. Egg congener concentrations at Bass Rock were typically 10-fold higher than at Ailsa Craig by 2002, and Principal Component Analysis indicated that colony differences were driven by the dominant congeners. Egg mercury concentrations were significantly lower at Bass Rock than at Ailsa Craig and temporal trends differed, there being a significant decline at Ailsa Craig but a marginal increase at Bass Rock. Our results suggest there may be differences in contamination between the eastern Atlantic and North Sea and/or there are colony differences in prey selection and associated contaminant loads. - Monitoring of PCBs and Hg in gannet eggs reveals contrasting temporal patterns between colonies on the eastern Atlantic and North Sea coasts of Britain

  9. Including land cover change in analysis of greenness trends using all available Landsat 5, 7, and 8 images: A case study from Guangzhou, China (2000–2014)

    Science.gov (United States)

    Zhu, Zhe; Fu, Yingchun; Woodcock, Curtis; Olofsson, Pontus; Vogelmann, James; Holden, Christopher; Wang, Min; Dai, Shu; Yu, Yang

    2016-01-01

    Remote sensing has proven a useful way of evaluating long-term trends in vegetation “greenness” through the use of vegetation indices like Normalized Differences Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). In particular, analyses of greenness trends have been performed for large areas (continents, for example) in an attempt to understand vegetation response to climate. These studies have been most often used coarse resolution sensors like Moderate Resolution Image Spectroradiometer (MODIS) and Advanced Very High Resolution Radiometer (AVHRR). However, trends in greenness are also important at more local scales, particularly in and around cities as vegetation offers a variety of valuable ecosystem services ranging from minimizing air pollution to mitigating urban heat island effects. To explore the ability to monitor greenness trends in and around cities, this paper presents a new way for analyzing greenness trends based on all available Landsat 5, 7, and 8 images and applies it to Guangzhou, China. This method is capable of including the effects of land cover change in the evaluation of greenness trends by separating the effects of abrupt and gradual changes, and providing information on the timing of greenness trends.

  10. Reversal of Long-Term Trends in Ethane Identified from the Global Atmosphere Watch Reactive Gases Measurement Network

    OpenAIRE

    Helmig, Detlev; Buchmann, Brigitte; Carpenter, Lucy; Claude, Anja; Emmons, Louisa; Flocke, Frank; Franco, Bruno; Galbally, Ian; Hannigan, James; Hueber, Jacques; Koide, Hiroshi; Lewis, Alastair; Masarie, Ken; Mahieu, Emmanuel; Montzka, Stephen

    2016-01-01

    Reactive gases play an important role in climate and air pollution issues. They control the self-cleansing capability of the troposphere, contribute to air pollution and acid deposition, regulate the lifetimes and provide tracers for deciphering sources and sinks for greenhouse gases. Within GAW, the focus is placed on long-term, high-quality observations of ozone (O3), carbon monoxide (CO), volatile organic compounds (VOC), nitrogen oxides (NOx), and sulfur dioxide (SO2). More than 100 stati...

  11. Long-term enhanced winter soil frost alters growing season CO2 fluxes through its impact on vegetation development in a boreal peatland.

    Science.gov (United States)

    Zhao, Junbin; Peichl, Matthias; Nilsson, Mats B

    2017-08-01

    At high latitudes, winter climate change alters snow cover and, consequently, may cause a sustained change in soil frost dynamics. Altered winter soil conditions could influence the ecosystem exchange of carbon dioxide (CO 2 ) and, in turn, provide feedbacks to ongoing climate change. To investigate the mechanisms that modify the peatland CO 2 exchange in response to altered winter soil frost, we conducted a snow exclusion experiment to enhance winter soil frost and to evaluate its short-term (1-3 years) and long-term (11 years) effects on CO 2 fluxes during subsequent growing seasons in a boreal peatland. In the first 3 years after initiating the treatment, no significant effects were observed on either gross primary production (GPP) or ecosystem respiration (ER). However, after 11 years, the temperature sensitivity of ER was reduced in the treatment plots relative to the control, resulting in an overall lower ER in the former. Furthermore, early growing season GPP was also lower in the treatment plots than in the controls during periods with photosynthetic photon flux density (PPFD) ≥800 μmol m -2  s -1 , corresponding to lower sedge leaf biomass in the treatment plots during the same period. During the peak growing season, a higher GPP was observed in the treatment plots under the low light condition (i.e. PPFD 400 μmol m -2  s -1 ) compared to the control. As Sphagnum moss maximizes photosynthesis at low light levels, this GPP difference between the plots may have been due to greater moss photosynthesis, as indicated by greater moss biomass production, in the treatment plots relative to the controls. Our study highlights the different responses to enhanced winter soil frost among plant functional types which regulate CO 2 fluxes, suggesting that winter climate change could considerably alter the growing season CO 2 exchange in boreal peatlands through its effect on vegetation development. © 2017 John Wiley & Sons Ltd.

  12. Kuchler Vegetation

    Data.gov (United States)

    California Natural Resource Agency — Digital version of potential natural plant communites as compiled and published on 'Map of the Natural Vegetation of California' by A. W. Kuchler, 1976. Source map...

  13. Wieslander Vegetation

    Data.gov (United States)

    California Natural Resource Agency — Digital version of the 1945 California Vegetation Type Maps by A. E. Wieslander of the U.S. Forest Service. Source scale of maps are 1:100,000. These compiled maps...

  14. Complex interplay between intrinsic and extrinsic drivers of long-term survival trends in southern elephant seals

    Directory of Open Access Journals (Sweden)

    McMahon Clive R

    2007-03-01

    Full Text Available Abstract Background Determining the relative contribution of intrinsic and extrinsic factors to fluctuations in population size, trends and demographic composition is analytically complex. It is often only possible to examine the combined effects of these factors through measurements made over long periods, spanning an array of population densities or levels of food availability. Using age-structured mark-recapture models and datasets spanning five decades (1950–1999, and two periods of differing relative population density, we estimated age-specific probabilities of survival and examined the combined effects of population density and environmental conditions on juvenile survival of southern elephant seals at Macquarie Island. Results First-year survival decreased with density during the period of highest population size, and survival increased during years when the Southern Oscillation Index (SOI anomaly (deviation from a 50-year mean during the mother's previous foraging trip to sea was positive (i.e., El Niño. However, when environmental stochasticity and density were considered together, the effect of density on first-year survival effectively disappeared. Ignoring density effects also leads to models placing too much emphasis on the environmental conditions prevailing during the naïve pup's first year at sea. Conclusion Our analyses revealed that both the state of the environment and population density combine to modify juvenile survival, but that the degree to which these processes contributed to the variation observed was interactive and complex. This underlines the importance of evaluating the relative contribution of both the intrinsic and extrinsic factors that regulate animal populations because false conclusions regarding the importance of population regulation may be reached if they are examined in isolation.

  15. Mapping long-term changes in savannah crop productivity in Senegal through trend analysis of time-series of remote sensing data

    DEFF Research Database (Denmark)

    Tøttrup, Christian; Rasmussen, Michael Schultz

    2004-01-01

    Remote sensing, NDVI, trend analysis, environmental change, rainfall, land cover change, Senegal......Remote sensing, NDVI, trend analysis, environmental change, rainfall, land cover change, Senegal...

  16. Editor's Choice - Prolonged ICU Length of Stay after AAA Repair: Analysis of Time Trends and Long-term Outcome.

    Science.gov (United States)

    Gavali, H; Mani, K; Tegler, G; Kawati, R; Covaciu, L; Wanhainen, A

    2017-08-01

    The aim of the study was to investigate the frequency and outcome of prolonged intensive care unit (ICU) length of stay (LOS) after abdominal aortic aneurysm (AAA) repair in the endovascular era. All patients operated on for AAA between 1999 and 2013 at Uppsala University hospital were identified. Data were retrieved from the Swedish Vascular registry, the Swedish Intensive Care registry, the National Population registry, and case records. Prolonged ICU LOS was defined as ≥ 48 h during the primary hospital stay. Patients surviving ≥ 48 h after AAA surgery were included in the analysis. A total of 725 patients were identified, of whom 707 (97.5%) survived ≥ 48 h; 563 (79.6%) underwent intact AAA repair and 144 (20.4%) ruptured AAA repair. A total of 548 patients (77.5%) required AAA repairs in 1999 to 7.3% in 2013 (p < .001) whereas the use of endovascular aortic repair (EVAR) increased from 6.9% in 1999 to 78.0% in 2013 (p < .001). The 30 day survival rate was 98.2% for those with < 48 h ICU stay versus 93.0% for 2-6 days versus 81.8% for ≥ 7 days (p < .001); the corresponding 90 day survival was 97.1% versus 86.1% versus 63.6% (p < .001) respectively. For patients surviving 90 days after repair, there was no difference in long-term survival between the groups. During the period of progressively increasing use of EVAR, a simultaneous significant reduction in frequency of prolonged ICU LOS occurred. Although prolonged ICU LOS was associated with a high short-term mortality, long-term outcome among those surviving the initial 90 days was less affected. Copyright © 2017 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  17. Long-term trend of haze pollution and impact of particulate matter in the Yangtze River Delta, China

    International Nuclear Information System (INIS)

    Cheng, Zhen; Wang, Shuxiao; Jiang, Jingkun; Fu, Qingyan; Chen, Changhong; Xu, Bingye; Yu, Jianqiao; Fu, Xiao; Hao, Jiming

    2013-01-01

    Haze pollution caused by heavy particulate matter (PM) loading brings significant damage in eastern China. Long-term monitoring from 1980 to 2011 and 1-year field measurement in 2011–2012 are used for investigating visibility variation and the impact of PM pollution for the Yangtze River Delta (YRD). It was found that visual range in the YRD endured a sharp reduction from 13.2 km to 10.5 km during 1980–2000. Average mass extinction efficiency (MEE) for inhalable PM (PM 10 ) is 2.25 m 2 /g in 2001–2011, and extinction coefficient due to PM 10 is 207 Mm −1 , accounting for 36.2% of total extinction coefficient. MEE of PM 2.5 and PM 2.5–10 are 4.08 m 2 /g and 0.58 m 2 /g, respectively. Extinction coefficient due to PM 2.5 and PM 2.5–10 is 198 Mm −1 (39.6%) and 20 Mm −1 (4.0%) in 2011–2012. Maximum daily concentration of PM 10 and PM 2.5 is estimated to be 63 μg/m 3 (RH: 73%) and 38 μg/m 3 (RH: 70%) to keep visual range above 10 km. Fine particulate matter is the key factor for haze pollution improvement in the YRD area. -- Highlights: •Long-term visual range variation and its causes in the Yangtze River Delta are analyzed. •Quantitative contribution of particulate matter to haze pollution is estimated. •Mass extinction efficiency of PM 10 , PM 2.5 , and PM 2.5–10 is estimated. -- The long-term variation of haze pollution in the YRD and its cause is investigated and the quantitative contribution of particulate matter to haze pollution is estimated

  18. Long-term Trends in Coral Reef Fish Yields and Exploitation Rates of Commercial Species from Coastal Kenya

    OpenAIRE

    Kaunda-Arara, B.; Rose, G.A.; Muchiri, M.S.; Kaka, R.

    2003-01-01

    Analysis of long-term (1978–2001) marine fisheries data showed that Kenyan coralreefs produced an estimated 2–4 metric t/km2/year of demersal fish. A rapid overall decline in landings occurred during the 1990s. Yields (t/km2/year) showed bimodal peaks in 1982 (2.98) and 1991 (2.90). The average total landings dropped by 55% during the last decade following peak landings in 1982. Landings of the commercially important families (e.g., Siganidae, Lethrinidae, Lutjanidae and Serran...

  19. Cadmium-related mortality and long-term secular trends in the cadmium body burden of an environmentally exposed population.

    Science.gov (United States)

    Nawrot, Tim S; Van Hecke, Etienne; Thijs, Lutgarde; Richart, Tom; Kuznetsova, Tatiana; Jin, Yu; Vangronsveld, Jaco; Roels, Harry A; Staessen, Jan A

    2008-12-01

    Few population studies have reported on the long-term changes in the internal cadmium dose and simultaneously occurring mortality. We monitored blood cadmium (BCd), 24-hr urinary cadmium (UCd), and mortality in an environmentally exposed population. Starting from 1985, we followed BCd (until 2003), UCd (until 1996), and mortality (until 2007) among 476 and 480 subjects, randomly recruited from low- exposure areas (LEA) and high-exposure areas (HEA). The last cadmium-producing plant in the HEA closed in 2002. From 1985-1989 to 1991-1996, BCd decreased by 40.3% and 18.9% in the LEA and HEA, respectively (p fashion without threshold.

  20. Long-term trends of suicide by choice of method in Norway: a joinpoint regression analysis of data from 1969 to 2012.

    Science.gov (United States)

    Puzo, Quirino; Qin, Ping; Mehlum, Lars

    2016-03-11

    Suicide mortality and the rates by specific methods in a population may change over time in response to concurrent changes in relevant factors in society. This study aimed to identify significant changing points in method-specific suicide mortality from 1969 to 2012 in Norway. Data on suicide mortality by specific methods and by sex and age were retrieved from the Norwegian Cause-of-Death Register. Long-term trends in age-standardized rates of suicide mortality were analyzed by using joinpoint regression analysis. The most frequently used suicide method in the total population was hanging, followed by poisoning and firearms. Men chose suicide by firearms more often than women, whereas poisoning and drowning were more frequently used by women. The joinpoint analysis revealed that the overall trend of suicide mortality significantly changed twice along the period of 1969 to 2012 for both sexes. The male age-standardized suicide rate increased by 3.1% per year until 1989, and decreased by 1.2% per year between 1994 and 2012. Among females the long-term suicide rate increased by 4.0% per year until 1988, decreased by 5.5% through 1995, and then stabilized. Both sexes experienced an upward trend for suicide by hanging during the 44-year observation period, with a particularly significant increase in 15-24 year old males. The most distinct change among men was seen for firearms after 1988 with a significant decrease through 2012 of around 5% per year. For women, significant reductions since 1985-88 were observed for suicide by drowning and poisoning. The present study demonstrates different time trends for different suicide methods with significant reductions in suicide by firearms, drowning and poisoning after the peak in the suicide rate in the late 1980s. Suicide by means of hanging continuously increased, but did not fully compensate for the reduced use of other methods. This lends some support for the effectiveness of method-specific suicide preventive measures

  1. Long-term trends in airborne SO2 in an air quality monitoring station in Seoul, Korea, from 1987 to 2013.

    Science.gov (United States)

    Khan, Azmatullah; Kim, Ki-Hyun; Szulejko, Jan E; Brown, Richard J C; Jeon, Eui-Chan; Oh, Jong-Min; Shin, Yong Soon; Adelodun, Adedeji A

    2017-08-01

    Atmospheric concentration of sulfur dioxide (SO 2 ) was intermittently measured at an air quality monitoring (AQM) station in the Yong-san district of Seoul, Korea, between 1987 and 2013. The SO 2 level was compared with other important pollutants concurrently measured, including methane (CH 4 ), carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO 2 ), ozone (O 3 ), and particulate matter (PM 10 ). If split into three different periods (period 1, 1987-1988, period 2, 1999-2000, and period 3, 2004-2013), the respective mean [SO 2 ] values (6.57 ± 4.29, 6.30 ± 2.44, and 5.29 ± 0.63 ppb) showed a slight reduction across the entire study period. The concentrations of SO 2 are found to be strongly correlated with other pollutants such as CO (r = 0.614, p = 0.02), which tracked reductions in reported emissions due to tighter emissions standards enacted by the South Korean government. There was also a clear seasonal trend in the SO 2 level, especially in periods 2 and 3, reflecting the combined effects of domestic heating by coal briquettes and meteorological conditions. Although only a 16% concentration reduction was achieved during the 27-year study duration, this is significant if one considers rapid urbanization, an 83.2% increase in population, and rapid industrialization that took place during that period. Since 1970, a network of air quality monitoring (AQM) stations has been operated by the Korean Ministry of Environment (KMOE) for routine nationwide monitoring of air pollutant concentrations in urban/suburban areas. To date, the information obtained from these stations has provided a platform for analyzing long-term trends of major pollutant species. In this study, we examined the long-term trends of SO 2 levels and relevant environmental parameters monitored continuously in the Yong-san district of Seoul between 1987 and 2013. The data were analyzed over various time scales (i.e., monthly, seasonal, and annual intervals). The results obtained from

  2. On the decline of the Rusty Blackbird and the use of ornithological literature to document long-term population trends

    Science.gov (United States)

    Greenberg, R.; Droege, S.

    1999-01-01

    Unlike most North American blackbirds, Rusty Blackbirds (Euphagus carolensis) have shown steep population declines. Declines of approximately 90% are indicated for three recent decades from the Breeding Bird Survey, Christmas Bird Counts, and Quebec Checklist Program. Analyses of abundance classifications in bird distribution books and annotated checklists reveal an overlooked but long-term decline dating back to at least the early part of this century. Rusty Blackbirds were described as very common to abundant in 5656 of the pre-192O published accounts, 19% of the 1921-1950 accounts, and only 7% of the post-1950 accounts. Rusty Blackbirds were described as uncommon in none of the pre-1950 accounts, 18% of the 1951-1980 accounts, and 43% of the post-1980 accounts. A similar pattern was found for analyses based on local checklists. Destruction of wooded wetlands on wintering grounds, acid precipitation, and the conversion of boreal forest wetlands could have contributed to these declines. Systematic analysis of regional guides and checklists provides a valuable tool for examining large-scale and long-term population changes in birds.

  3. Long-Term Trends and Variability in Spring Development of Calanus finmarchicus in the Southeastern Norwegian Sea during 1996-2012

    Science.gov (United States)

    Dupont, N.; Bagøien, E.; Melle, W.

    2016-02-01

    Calanus finmarchicus is the dominant copepod species in the Norwegian Sea in terms of biomass, playing a key role in the ecosystem by transferring energy from primary producers to higher trophic levels. This study analyses the long-term trend of a 17-year time series (1996-2012) on abundance of adult Calanus finmarchicus in the Atlantic water-mass of the southern Norwegian Sea during spring. The long-term trend in spring abundance was assessed by using Generalised Additive Models, while simultaneously accounting for both general population development and inter-annual variation in population development throughout the study period. In one model, we focus on inter-annual changes in timing of the Calanus spring seasonal development by including Mean Stage Composition as a measure for state of population development. Following a short increase during the years 1996 to 2000, the abundance of Calanus finmarchicus decreased strongly until about the year 2010. For the two last years of the studied period, 2011-2012, increasing population abundances are suggested but with less certainty. The model results suggest that the analysis is capturing the G0 generation, displaying a peak for the adults in about mid-April. Inter-annual differences in spring seasonal development, with the peak of adults shifting towards earlier in the season as well as a shorter generation time are suggested. Considering the importance of Calanus finmarchicus as food for planktivorous predators in the Norwegian Sea, our time series analysis suggests relevant changes both with respect to the spring abundance and timing of this food source. The next step is to relate variation in the Calanus time series to environmental factors with special emphasis on climatic drivers.

  4. Diagnosis of vegetation recovery within herbaceous sub-systems in the West African Sahel Region

    Science.gov (United States)

    Anchang, J.; Hanan, N. P.; Prihodko, L.; Sathyachandran, S. K.; Ji, W.; Ross, C. W.

    2017-12-01

    The West African Sahel (WAS) region is an extensive water limited environment that features a delicate balance of herbaceous and woody vegetation sub systems. These play an important role in the cycling of carbon while also supporting the dominant agro-pastoral human activities in the region. Quantifying the temporal trends in vegetation with regard to these two systems is therefore very important in assessing resource sustainability and food security. In water limited areas, rainfall is a primary driver of vegetation productivity and past watershed scale studies in the WAS region have shown that increase in the slope of the productivity-to-rainfall relationship is indicative of increasing cover and density of herbaceous plants. Given the importance of grazing resources to the region, we perform a wall-to-wall pixel based analysis of changing short-term vegetation sensitivity to changing annual rainfall (hereafter referred to as dS) to examine temporal trends in herbaceous vegetation health. Results indicate that 43% of the Sahelian region has experienced changes (P Western and Central Mali and South Western Niger. Positive dS is indicative of herbaceous vegetation recovery, in response to changing management and rainfall conditions that promote long-term herbaceous community recovery following degradation during the 1970-1980s droughts.

  5. Long-term Measurements of Summer-time Ozone at the Walnut Grove Tower - Understanding Trends in the Boundary Layer

    Science.gov (United States)

    Mahmud, A.; Di, P.; Mims, D.; Avise, J.; DaMassa, J.; Kaduwela, A. P.

    2015-12-01

    The California Air Resources Board (CARB) has been monitoring boundary layer ozone at the Walnut Grove Tower (WGT) since 1996 for investigating regional transport and vertical profile. Walnut Grove is located between Sacramento and Stockton, CA in the Sacramento - San Joaquin Delta. Sampling inlets are positioned at 30-ft, 400-ft, 800-ft, 1200-ft and 1600-ft levels of the 2000-ft tower, which is one of the tallest monitoring towers in the Western US. Ozone, ambient temperature, wind speed, and wind direction are simultaneously measured at each level, and reported as hourly averages. The current study included analyses of available ozone and corresponding meteorological data for the months of June - September from 1996 - 2014 with objectives to: 1) explore trends and inter-annual variability of ozone, 2) examine any correlations between ozone and meteorological parameters, 3) understand interactions of ozone measured at various levels, and 4) assess how well a regulatory state-of-the-science air quality model such as the Community Multi-scale Air Quality Model (CMAQ) captures observation. Daily 1-hr maximum ozone has been consistently decreasing during the 1996 - 2014 period at a rate of ~1 ppb per year. This indicates that CARB's measures to control ambient ozone have been effective over the past years. Evolution of the vertical profile throughout the day shows that ozone is fairly homogeneously mixed between 1 - 5 pm, when mixing height typically reaches the maximum. Ozone at 30-ft shows the greatest variability because of its proximity to the ground and emissions sources - rises faster during morning hours (7 - 10 am) and declines more rapidly during evening hours (7 - 10 pm) compared to other levels. Air masses reaching the tower are predominantly southwesterly (247 - 257 deg.) at the bottom, and southwesterly to slightly northwesterly (254 - 302 deg.) at top levels. Daily 1-hr maximum ozone was negatively correlated with wind speed (i.e. ozone was high under

  6. Long-term trends in the prevalence of patients hospitalized with ischemic stroke from 1995 to 2010 in Sweden.

    Directory of Open Access Journals (Sweden)

    Kok Wai Giang

    Full Text Available The prevalence of stroke is expected to increase partly because of prolonged life expectancy in the general population. The objective of this study was to investigate trends in the prevalence of patients hospitalized with ischemic stroke (IS in Sweden from 1995-2010.The Swedish inpatient and cause-specific death registries were used to estimate the absolute numbers and prevalence of patients who were hospitalized with and survived an IS from 1995-2010.The overall number of IS increased from 129,418 in 1995 to 148,778 in 2010. In 1995, the prevalence of IS was 189 patients per 10,000 population. An increase in overall prevalence was observed until 2000, and then it remained stable, followed by a decline with an annual percentage change of (APC -0.8% (95% CI -1.0 to 0.6 and with a final prevalence of 199 patients per 10,000 population in 2010. The prevalence of IS in people aged <45 years increased from 6.4 in 1995 to 7.6 patients per 10,000 population in 2010, with an APC of 2.1% (95% CI 0.9 to 3.4 from 1995-1998 and 0.7% (95% CI 0.6-0.9 from 1998-2010. Among those aged 45-54 years, the prevalence rose through the mid to late 1990s, followed by a slight decrease (APC: -0.7%, 95% CI-1.1 to -0.4 until 2006 and then remained stable with a prevalence of 43.8 patients per 10,000 population in 2010. Among ≥85 years, there was a minor decrease (APC: -0.3%, 95% CI -0.5 to -0.1 in overall prevalence after 2002 from 1481 to 1453 patients per 10,000 population in 2010.The overall prevalence of IS increased until 2000, but then remained stable followed by a slight decline. However, the prevalence of IS in the young increased through the study period. The absolute number of IS survivors has markedly increased, mainly because of demographic changes.

  7. Roles of patch characteristics, drought frequency, and restoration in long-term trends of a widespread amphibian.

    Science.gov (United States)

    Hossack, Blake R; Adams, Michael J; Pearl, Christopher A; Wilson, Kristine W; Bull, Evelyn L; Lohr, Kristin; Patla, Debra; Pilliod, David S; Jones, Jason M; Wheeler, Kevin K; McKay, Samuel P; Corn, Paul Stephen

    2013-12-01

    Despite the high profile of amphibian declines and the increasing threat of drought and fragmentation to aquatic ecosystems, few studies have examined long-term rates of change for a single species across a large geographic area. We analyzed growth in annual egg-mass counts of the Columbia spotted frog (Rana luteiventris) across the northwestern United States, an area encompassing 3 genetic clades. On the basis of data collected by multiple partners from 98 water bodies between 1991 and 2011, we used state-space and linear-regression models to measure effects of patch characteristics, frequency of summer drought, and wetland restoration on population growth. Abundance increased in the 2 clades with greatest decline history, but declined where populations are considered most secure. Population growth was negatively associated with temporary hydroperiods and landscape modification (measured by the human footprint index), but was similar in modified and natural water bodies. The effect of drought was mediated by the size of the water body: populations in large water bodies maintained positive growth despite drought, whereas drought magnified declines in small water bodies. Rapid growth in restored wetlands in areas of historical population declines provided strong evidence of successful management. Our results highlight the importance of maintaining large areas of habitat and underscore the greater vulnerability of small areas of habitat to environmental stochasticity. Similar long-term growth rates in modified and natural water bodies and rapid, positive responses to restoration suggest pond construction and other forms of management can effectively increase population growth. These tools are likely to become increasingly important to mitigate effects of increased drought expected from global climate change. Papeles de las Características del Fragmento, Frecuencia de Sequía y Restauración en las Tendencias a Largo Plazo de un Anfibio Ampliamente Distribuido

  8. Roles of patch characteristics, drought frequency, and restoration in long-term trends of a widespread amphibian

    Science.gov (United States)

    Hossack, Blake R.; Adams, Michael J.; Pearl, Christopher A.; Pilliod, David S.; Corn, P. Stephen; , KRISTINE W. WILSON; , EVELYN L. BULL; , KRISTIN LOHR; , DEBRA PATLA; , JASON JONES

    2013-01-01

    Despite the high profile of amphibian declines and the increasing threat of drought and fragmentation to aquatic ecosystems, few studies have examined long-term rates of change for a single species across a large geographic area. We analyzed growth in annual egg-mass counts of the Columbia spotted frog (Rana luteiventris) across the northwestern United States, an area encompassing 3 genetic clades. On the basis of data collected by multiple partners from 98 water bodies between 1991 and 2011, we used state-space and linear-regression models to measure effects of patch characteristics, frequency of summer drought, and wetland restoration on population growth. Abundance increased in the 2 clades with greatest decline history, but declined where populations are considered most secure. Population growth was negatively associated with temporary hydroperiods and landscape modification (measured by the human footprint index), but was similar in modified and natural water bodies. The effect of drought was mediated by the size of the water body: populations in large water bodies maintained positive growth despite drought, whereas drought magnified declines in small water bodies. Rapid growth in restored wetlands in areas of historical population declines provided strong evidence of successful management. Our results highlight the importance of maintaining large areas of habitat and underscore the greater vulnerability of small areas of habitat to environmental stochasticity. Similar long-term growth rates in modified and natural water bodies and rapid, positive responses to restoration suggest pond construction and other forms of management can effectively increase population growth. These tools are likely to become increasingly important to mitigate effects of increased drought expected from global climate change.

  9. Long-Term Vegetation Dynamics in a Megadiverse Hotspot: The Ice-Age Record of a Pre-montane Forest of Central Ecuador

    Directory of Open Access Journals (Sweden)

    Encarni Montoya

    2018-02-01

    Full Text Available Tropical ecosystems play a key role in many aspects of Earth system dynamics currently of global concern, including carbon sequestration and biodiversity. To accurately understand complex tropical systems it is necessary to parameterise key ecological aspects, such as rates of change (RoC, species turnover, dynamism, resilience, or stability. To obtain a long-term (>50 years perspective on these ecological aspects we must turn to the fossil record. However, compared to temperate zones, collecting continuous sedimentary archives in the lowland tropics is often difficult due to the active landscape processes, with potentially frequent volcanic, tectonic, and/or fluvial events confounding sediment deposition, preservation, and recovery. Consequently, the nature, and drivers, of vegetation dynamics during the last glacial are barely known from many non-montane tropical landscapes. One of the first lowland Amazonian locations from which palaeoecological data were obtained was an outcrop near Mera (Ecuador. Mera was discovered, and analysed, by Paul Colinvaux in the 1980s, but his interpretation of the data as indicative of a forested glacial period were criticised based on the ecology and age control. Here we present new palaeoecological data from a lake located less than 10 km away from Mera. Sediment cores raised from Laguna Pindo (1250 masl; 1°27′S, 78°05′W have been shown to span the late last glacial period [50–13 cal kyr BP (calibrated kiloyears before present]. The palaeoecological information obtained from Laguna Pindo indicate that the region was characterised by a relatively stable plant community, formed by taxa nowadays common at both mid and high elevations. Miconia was the dominant taxon until around 30 cal kyr BP, when it was replaced by Hedyosmum, Asteraceae and Ilex among other taxa. Heat intolerant taxa including Podocarpus, Alnus, and Myrica peaked around the onset of the Last Glacial Maximum (c. 21 cal kyr BP. The results

  10. Long-term vegetation, climate and ocean dynamics inferred from a 73,500 years old marine sediment core (GeoB2107-3) off southern Brazil

    Science.gov (United States)

    Gu, Fang; Zonneveld, Karin A. F.; Chiessi, Cristiano M.; Arz, Helge W.; Pätzold, Jürgen; Behling, Hermann

    2017-09-01

    Long-term changes in vegetation and climate of southern Brazil, as well as ocean dynamics of the adjacent South Atlantic, were studied by analyses of pollen, spores and organic-walled dinoflagellate cysts (dinocysts) in marine sediment core GeoB2107-3 collected offshore southern Brazil covering the last 73.5 cal kyr BP. The pollen record indicates that grasslands were much more frequent in the landscapes of southern Brazil during the last glacial period if compared to the late Holocene, reflecting relatively colder and/or less humid climatic conditions. Patches of forest occurred in the lowlands and probably also on the exposed continental shelf that was mainly covered by salt marshes. Interestingly, drought-susceptible Araucaria trees were frequent in the highlands (with a similar abundance as during the late Holocene) until 65 cal kyr BP, but were rare during the following glacial period. Atlantic rainforest was present in the northern lowlands of southern Brazil during the recorded last glacial period, but was strongly reduced from 38.5 until 13.0 cal kyr BP. The reduction was probably controlled by colder and/or less humid climatic conditions. Atlantic rainforest expanded to the south since the Lateglacial period, while Araucaria forests advanced in the highlands only during the late Holocene. Dinocysts data indicate that the Brazil Current (BC) with its warm, salty and nutrient-poor waters influenced the study area throughout the investigated period. However, variations in the proportion of dinocyst taxa indicating an eutrophic environment reflect the input of nutrients transported mainly by the Brazilian Coastal Current (BCC) and partly discharged by the Rio Itajaí (the major river closest to the core site). This was strongly related to changes in sea level. A stronger influence of the BCC with nutrient rich waters occurred during Marine Isotope Stage (MIS) 4 and in particular during the late MIS 3 and MIS 2 under low sea level. Evidence of Nothofagus pollen

  11. Long-term trends in first arrival and first egg laying dates of some migrant and resident bird species in northern Italy

    Science.gov (United States)

    Rubolini, Diego; Ambrosini, Roberto; Caffi, Mario; Brichetti, Pierandrea; Armiraglio, Stefano; Saino, Nicola

    2007-08-01

    Climate change is affecting the phenology of seasonal events in Europe and the Northern Hemisphere, as shown by several studies of birds’ timing of migration and reproduction. Here, we analyse the long-term (1982-2006) trends of first arrival dates of four long-distance migratory birds [swift ( Apus apus), nightingale ( Luscinia megarhynchos), barn swallow ( Hirundo rustica), and house martin ( Delichon urbicum)] and first egg laying dates of two migrant (swift, barn swallow) and two resident species [starling ( Sturnus vulgaris), Italian sparrow ( Passer italiae)] at a study site in northern Italy. We also addressed the effects of local weather (temperature and precipitation) and a climate index (the North Atlantic Oscillation, NAO) on the interannual variability of phenological events. We found that the swift and the barn swallow significantly advanced both arrival and laying dates, whereas all other species did not show any significant temporal trend in either arrival or laying date. The earlier arrival of swifts was explained by increasing local temperatures in April, whereas this was not the case for arrival dates of swallows and first egg laying dates of both species. In addition, arrival dates of house martins were earlier following high NAO winters, while nightingale arrival was earlier when local spring rainfall was greater. Finally, Italian sparrow onset of reproduction was anticipated by greater spring rainfall, but delayed by high spring NAO anomalies, and swift’s onset of reproduction was anticipated by abundant rainfall prior to reproduction. There were no significant temporal trends in the interval between onset of laying and arrival in either the swift or the barn swallow. Our findings therefore indicate that birds may show idiosyncratic responses to climate variability at different spatial scales, though some species may be adjusting their calendar to rapidly changing climatic conditions.

  12. Long-Term Trends and Temporal Synchrony in Plankton Richness, Diversity and Biomass Driven by Re-Oligotrophication and Climate across 17 Danish Lakes

    Directory of Open Access Journals (Sweden)

    Korhan Özkan

    2016-09-01

    Full Text Available A two-decade (1989–2008 time series of lake phyto- and zooplankton, water characteristics and climate in 17 Danish lakes was analysed to examine the long term changes and the effects of lake restoration efforts. The analyses of the pair-wise correlations across time series revealed a strong synchrony in climatic variables among the lakes. A significant, but weak increase in air temperature was observed and resulted in a corresponding increase in surface water temperature only in summer. Lake physico-chemical variables had weaker synchrony than climatic variables. Synchrony in water temperature and stratification was stronger than lake chemistry as the former is mostly affected by atmospheric energy flux. Synchrony in the taxonomic richness of the plankton groups and phytoplankton biomass was apparent, to a similar degree as observed for lake chemistry. The synchrony and the temporal trends in lake chemistry and plankton were more pronounced for the lakes with strong re-oligotrophication. Phytoplankton biomass decreased and plankton richness increased in these lakes, with a shift from Chlorophyta dominance towards more heterogeneous phytoplankton communities. Notably, a widespread significant positive trend in plankton richness was observed not only in lakes with strong re-oligotrophication but across all lakes. The widespread increase in plankton richness coincided with widespread decrease in phosphate and total nitrogen concentrations, as well as with the trends in climate indicating a likely joint effect of nutrient reduction and climate in driving lake plankton. However, temporal changes and synchrony as well as the recovery of richness and composition of lake plankton more coherently corresponded with the nutrient loading reduction across the Danish landscape, while the role of climate control of the lake plankton was less pronounced.

  13. Temporal Trends in Analgesic Use in Long-Term Care Facilities: A Systematic Review of International Prescribing.

    Science.gov (United States)

    La Frenais, Francesca L; Bedder, Rachel; Vickerstaff, Victoria; Stone, Patrick; Sampson, Elizabeth L

    2018-02-01

    To explore global changes in the prescription of analgesic drugs over time in the international long-term care (LTC) population. Systematic review. We included original research articles in English, published and unpublished, that included number of participants, country and year(s) of data collection, and prescription of analgesics (analgesics not otherwise specified, opioids, acetaminophen; scheduled only, or scheduled plus as needed (PRN)). LTC residents. We searched PubMed, EMBASE, CINAHL, International Pharmaceutical Abstracts, PsycINFO, Cochrane, Web of Science, Google Scholar, using keywords for LTC facilities and analgesic medication; hand-searched references of eligible papers; correspondence. Studies were quality rated using an adapted Newcastle-Ottawa scale. Pearson correlation coefficients were generated between percentage of residents prescribed an analgesic and year of data collection. If available, we investigated changes in acetaminophen and opioid prescriptions. Forty studies met inclusion criteria. A moderate correlation (0.59) suggested that scheduled prescription rates for analgesics have increased over time. Similar findings were reflected in scheduled prescriptions for acetaminophen and opioids. No increase was seen when analyzing scheduled plus PRN analgesics. Use of opioids (scheduled plus PRN) appears to have increased over time. Worldwide, use of opioids and acetaminophen has increased in LTC residents. Research is needed to explore whether this reflects appropriate pain management for LTC residents and if PRN medication is used effectively. © 2017 The Authors. Journal of the American Geriatrics Society published by Wiley Periodicals, Inc. on behalf of The American Geriatrics Society.

  14. Uncertainties in satellite remote sensing of aerosols and impact on monitoring its long-term trend: a review and perspective

    Directory of Open Access Journals (Sweden)

    Z. Li

    2009-07-01

    Full Text Available As a result of increasing attention paid to aerosols in climate studies, numerous global satellite aerosol products have been generated. Aerosol parameters and underlining physical processes are now incorporated in many general circulation models (GCMs in order to account for their direct and indirect effects on the earth's climate, through their interactions with the energy and water cycles. There exists, however, an outstanding problem that these satellite products have substantial discrepancies, that must be lowered substantially for narrowing the range of the estimates of aerosol's climate effects. In this paper, numerous key uncertain factors in the retrieval of aerosol optical depth (AOD are articulated for some widely used and relatively long satellite aerosol products including the AVHRR, TOMS, MODIS, MISR, and SeaWiFS. We systematically review the algorithms developed for these sensors in terms of four key elements that influence the quality of passive satellite aerosol retrieval: calibration, cloud screening, classification of aerosol types, and surface effects. To gain further insights into these uncertain factors, the NOAA AVHRR data are employed to conduct various tests, which help estimate the ranges of uncertainties incurred by each of the factors. At the end, recommendations are made to cope with these issues and to produce a consistent and unified aerosol database of high quality for both environment monitoring and climate studies.

  15. The long-term supply/demand trend of world energy and the current oil situation in the Asia

    International Nuclear Information System (INIS)

    Okamoto, Hiroyuki

    1996-01-01

    Total world primary energy consumption excluding the FSU increased by 2.9% in 1995, which is somewhat above the 10 year average rate of 2.4%. This reflected strong economic growth in most parts of the world. The increase in demand confirmed the recovery of the link between the economic growth and consumption of primary energy, which broke down in the period of oil crises. Oil demand in the Asian Emerging Market Economies has continued to be very strong. Oil demand has doubled in a decade in this region and is now one sixth of world consumption. Malaysia was the fastest growing oil market in the world in 1995 at 15.5%. In volume terms, S. Korea grew the most in the world by 170,000 b/d, closely followed by China and India. Because of the fast growing oil demand, many energy economists expect a tight supply situation in the Asian oil market in the early 21st Century. However, recent technological developments would be able to supply crude oil appropriate for an increase in oil demand. (author)

  16. Hydrological influences on long-term gas flow trends at locations in the Vogtland/NW Bohemian seismic region (German-Czech border

    Directory of Open Access Journals (Sweden)

    J. Heinicke

    2007-06-01

    Full Text Available One of the typical methods for the identification of seismo-hydrological effects is to monitor changes in the free gas flow throughout springs or mofettes. For several years, the gas flow regime of mineral springs at Bad Brambach (Germany and mofettes in the Nature Park Soos (Czech Republic and its dependence on hydro-/meteorological parameters have been studied. The mineral spring ‘Wettinquelle’, Bad Brambach, is a well-known seismo- hydrologically sensitive location for swarmquakes at a special epicentral area of NW Bohemia. Since 2000, a slight upward trend in the gas flow of three Bad Brambach mineral springs has been observed, which became stronger after the ‘Eisenquelle’ spring capture reconstruction (winter 2003/2004. Similar behaviour could be detected at a mofette in Soos. The results correspond to a 3He/4He mantle ratio increase in gases at mofettes in the Cheb Basin (CZ traced by other authors for more than 12 years, and could give hints for a higher degassing activity of the magma body below that area. Common and special properties in the degassing regimes of the Bad Brambach and Soos locations are discussed. It is demonstrated that the long-term gas flow trend was interrupted in 2003 because of very low groundwater levels. This effect was amplified by the artificial groundwater lowering during the ‘Eisenquelle’ spring capture reconstruction.

  17. Long-Term Trends, Variability and Extremes of In Situ Sea Surface Temperature Measured Along the Eastern Adriatic Coast and its Relationship to Hemispheric Processes

    Science.gov (United States)

    Grbec, Branka; Matić, Frano; Beg Paklar, Gordana; Morović, Mira; Popović, Ružica; Vilibić, Ivica

    2018-02-01

    This paper examines long-term series of in situ sea surface temperature (SST) data measured at nine coastal and one open sea stations along the eastern Adriatic Sea for the period 1959-2015. Monthly and yearly averages were used to document SST trends and variability, while clustering and connections to hemispheric indices were achieved by applying the Principal Component Analysis (PCA) and Self-Organizing Maps (SOM) method. Both PCA and SOM revealed the dominance of temporal changes with respect to the effects of spatial differences in SST anomalies, indicating the prevalence of hemispheric processes over local dynamics, such as bora wind spatial inhomogeneity. SST extremes were connected with blocking atmospheric patterns. A substantial warming between 1979 and 2015, in total exceeding 1 °C, was preceded by a period with a negative SST trend, implying strong multidecadal variability in the Adriatic. The strongest connection was found between yearly SST and the East Atlantic (EA) pattern, while North Atlantic Oscillation (NAO) and East Atlantic/West Russia (EAWR) patterns were found to also affect February SST values. Quantification of the Adriatic SST and their connection to hemispheric indices allow for more precise projections of future SST, considered to be rather important for Adriatic thermohaline circulation, biogeochemistry and fisheries, and sensitive to ongoing climate change.

  18. Quasi-biennial oscillation in atmospheric ozone, and its possible consequences for damaging UV-B radiation and for determination of long-term ozone trends

    Energy Technology Data Exchange (ETDEWEB)

    Gruzdev, A N [Russian Academy of Sciences, Moscow (Russian Federation). Inst. of Atmospheric Physics

    1996-12-31

    The quasi-biennial oscillation (QBO) in ozone is supposed to be related to the QBO of zonal wind in the tropical stratosphere, with an approximate period of 29 months. Generally speaking, mechanisms of QBO-related effects in the extratropical atmosphere should depend on season and region, resulting in other periodicities (e.g., a 20-month periodicity) due to nonlinear interaction between the `pure` QBO and an annual cycle. Seasonal and regional dependences of QBO-related effects in ozone not only influence the regime of ozone variability itself, but can have important consequences, for example, for interannual changes in biologically active UV-B radiation and for determination of long-term ozone trends. This work is concerned with these problems

  19. Quasi-biennial oscillation in atmospheric ozone, and its possible consequences for damaging UV-B radiation and for determination of long-term ozone trends

    Energy Technology Data Exchange (ETDEWEB)

    Gruzdev, A.N. [Russian Academy of Sciences, Moscow (Russian Federation). Inst. of Atmospheric Physics

    1995-12-31

    The quasi-biennial oscillation (QBO) in ozone is supposed to be related to the QBO of zonal wind in the tropical stratosphere, with an approximate period of 29 months. Generally speaking, mechanisms of QBO-related effects in the extratropical atmosphere should depend on season and region, resulting in other periodicities (e.g., a 20-month periodicity) due to nonlinear interaction between the `pure` QBO and an annual cycle. Seasonal and regional dependences of QBO-related effects in ozone not only influence the regime of ozone variability itself, but can have important consequences, for example, for interannual changes in biologically active UV-B radiation and for determination of long-term ozone trends. This work is concerned with these problems

  20. Assessment of the Long Term Trends in Extreme Heat Events and the Associated Health Impacts in the United States

    Science.gov (United States)

    Bell, J.; Rennie, J.; Kunkel, K.; Herring, S.; Cullen, H. M.

    2017-12-01

    Land surface air temperature products have been essential for monitoring the evolution of the climate system. Before a temperature dataset is included in such reports, it is important that non-climatic influences be removed or changed so the dataset is considered homogenous. These inhomogeneities include changes in station location, instrumentation and observing practices. While many homogenized products exist on the monthly time scale, few daily products exist, due to the complication of removing breakpoints that are truly inhomogeneous rather than solely by chance (for example, sharp changes due to synoptic conditions). Recently, a sub monthly homogenized dataset has been developed using data and software provided by NOAA's National Centers for Environmental Information (NCEI). Homogeneous daily data are useful for identification and attribution of extreme heat events over a period of time. Projections of increasing temperatures are expected to result in corresponding increases in the frequency, duration, and intensity of extreme heat events. It is also established that extreme heat events can have significant public health impacts, including short-term increases in mortality and morbidity. In addition, it can exacerbate chronic health conditions in vulnerable populations, including renal and cardiovascular issues. To understand how heat events impact a specific population, it will be important to connect observations on the duration and intensity of extreme heat events with health impacts data including insurance claims and hospital admissions data. This presentation will explain the methodology to identify extreme heat events, provide a climatology of heat event onset, length and severity, and explore a case study of an anomalous heat event with available health data.

  1. Effects of silver nitrate and silver nanoparticles on a planktonic community: general trends after short-term exposure.

    Directory of Open Access Journals (Sweden)

    Jens Boenigk

    Full Text Available Among metal pollutants silver ions are one of the most toxic forms, and have thus been assigned to the highest toxicity class. Its toxicity to a wide range of microorganisms combined with its low toxicity to humans lead to the development of a wealth of silver-based products in many bactericidal applications accounting to more than 1000 nano-technology-based consumer products. Accordingly, silver is a widely distributed metal in the environment originating from its different forms of application as metal, salt and nanoparticle. A realistic assessment of silver nanoparticle toxicity in natural waters is, however, problematic and needs to be linked to experimental approaches. Here we apply metatranscriptome sequencing allowing for elucidating reactions of whole communities present in a water sample to stressors. We compared the toxicity of ionic silver and ligand-free silver nanoparticles by short term exposure on a natural community of aquatic microorganisms. We analyzed the effects of the treatments on metabolic pathways and species composition on the eukaryote metatranscriptome level in order to describe immediate molecular responses of organisms using a community approach. We found significant differences between the samples treated with 5 µg/L AgNO3 compared to the controls, but no significant differences in the samples treated with AgNP compared to the control samples. Statistical analysis yielded 126 genes (KO-IDs with significant differential expression with a false discovery rate (FDR <0.05 between the control (KO and AgNO3 (NO3 groups. A KEGG pathway enrichment analysis showed significant results with a FDR below 0.05 for pathways related to photosynthesis. Our study therefore supports the view that ionic silver rather than silver nanoparticles are responsible for silver toxicity. Nevertheless, our results highlight the strength of metatranscriptome approaches for assessing metal toxicity on aquatic communities.

  2. VEGETATION MAPPING IN WETLANDS

    Directory of Open Access Journals (Sweden)

    F. PEDROTTI

    2004-01-01

    Full Text Available The current work examines the main aspects of wetland vegetation mapping, which can be summarized as analysis of the ecological-vegetational (ecotone gradients; vegetation complexes; relationships between vegetation distribution and geomorphology; vegetation of the hydrographic basin lo which the wetland in question belongs; vegetation monitoring with help of four vegetation maps: phytosociological map of the real and potential vegetation, map of vegetation dynamical tendencies, map of vegetation series.

  3. A model approach to assess the long-term trends of indirect photochemistry in lake water. The case of Lake Maggiore (NW Italy).

    Science.gov (United States)

    Minella, Marco; Rogora, Michela; Vione, Davide; Maurino, Valter; Minero, Claudio

    2011-08-15

    A model-based approach is here developed and applied to predict the long-term trends of indirect photochemical processes in the surface layer (5m water depth) of Lake Maggiore, NW Italy. For this lake, time series of the main parameters of photochemical importance that cover almost two decades are available. As a way to assess the relevant photochemical reactions, the modelled steady-state concentrations of important photogenerated transients ((•)OH, ³CDOM* and CO₃(-•)) were taken into account. A multivariate analysis approach was adopted to have an overview of the system, to emphasise relationships among chemical, photochemical and seasonal variables, and to highlight annual and long-term trends. Over the considered time period, because of the decrease of the dissolved organic carbon (DOC) content of water and of the increase of alkalinity, a significant increase is predicted for the steady-state concentrations of the radicals (•)OH and CO₃(-•). Therefore, the photochemical degradation processes that involve the two radical species would be enhanced. Another issue of potential photochemical importance is related to the winter maxima of nitrate (a photochemical (•)OH source) and the summer maxima of DOC ((•)OH sink and ³CDOM* source) in the lake water under consideration. From the combination of sunlight irradiance and chemical composition data, one predicts that the processes involving (•)OH and CO₃(-•) would be most important in spring, while the reactions involving ³CDOM* would be most important in summer. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Assessing global vegetation activity using spatio-temporal Bayesian modelling

    Science.gov (United States)

    Mulder, Vera L.; van Eck, Christel M.; Friedlingstein, Pierre; Regnier, Pierre A. G.

    2016-04-01

    This work demonstrates the potential of modelling vegetation activity using a hierarchical Bayesian spatio-temporal model. This approach allows modelling changes in vegetation and climate simultaneous in space and time. Changes of vegetation activity such as phenology are modelled as a dynamic process depending on climate variability in both space and time. Additionally, differences in observed vegetation status can be contributed to other abiotic ecosystem properties, e.g. soil and terrain properties. Although these properties do not change in time, they do change in space and may provide valuable information in addition to the climate dynamics. The spatio-temporal Bayesian models were calibrated at a regional scale because the local trends in space and time can be better captured by the model. The regional subsets were defined according to the SREX segmentation, as defined by the IPCC. Each region is considered being relatively homogeneous in terms of large-scale climate and biomes, still capturing small-scale (grid-cell level) variability. Modelling within these regions is hence expected to be less uncertain due to the absence of these large-scale patterns, compared to a global approach. This overall modelling approach allows the comparison of model behavior for the different regions and may provide insights on the main dynamic processes driving the interaction between vegetation and climate within different regions. The data employed in this study encompasses the global datasets for soil properties (SoilGrids), terrain properties (Global Relief Model based on SRTM DEM and ETOPO), monthly time series of satellite-derived vegetation indices (GIMMS NDVI3g) and climate variables (Princeton Meteorological Forcing Dataset). The findings proved the potential of a spatio-temporal Bayesian modelling approach for assessing vegetation dynamics, at a regional scale. The observed interrelationships of the employed data and the different spatial and temporal trends support

  5. Long-term trend in ground-based air temperature and its responses to atmospheric circulation and anthropogenic activity in the Yangtze River Delta, China

    Science.gov (United States)

    Peng, Xia; She, Qiannan; Long, Lingbo; Liu, Min; Xu, Qian; Zhang, Jiaxin; Xiang, Weining

    2017-10-01

    The Yangtze River Delta (YRD), including Shanghai City, Jiangsu and Zhejiang Provinces, is the largest metropolitan region in China. In the past decades, the region has experienced massive urbanization and detrimentally affected the environment in the region. Identifying the spatio-temporal variations of climate change and its influencing mechanism in the YRD is an important task for assessing their impacts on the local society and ecosystem. Based on long-term (1958-2014) observation data of meteorological stations, three temperature indices, i.e. extreme maximum temperature (TXx), extreme minimum temperature (TNn), and mean temperature (TMm), were selected and spatialized with climatological calculations and spatial techniques. Evolution and spatial heterogeneity of three temperature indices over YRD as well as their links to atmospheric circulation and anthropogenic activity were investigated. In the whole YRD, a statistically significant overall uptrend could be detected in three temperature indices with the Mann-Kendall (M-K) trend test method. The linear increasing trend for TMm was 0.31 °C/10 a, which was higher than the global average (0.12 °C/10 a during 1951-2012). For TXx and TNn, the increasing rates were 0.41 °C/10 a and 0.52 °C/10 a. Partial correlation analysis indicated that TMm was more related with TXx (rp = 0.68, p < 0.001) than TNn (rp = 0.48, p < 0.001). Furthermore, it was detected with M-K analysis at pixel scale that 62.17%, 96.75% and 97.05% of the areas in the YRD showed significant increasing trends for TXx, TNn and TMm, respectively. The increasing trend was more obvious in the southern mountainous areas than the northern plains areas. Further analysis indicated that the variation of TXx over YRD was mainly influenced by anthropogenic activities (e.g. economic development), while TNn was more affected by atmospheric circulations (e.g., the Eurasian zonal circulation index (EAZ) and the cold air activity index (CA)). For TMm, it was a

  6. Long-term trends of surface-water mercury and methylmercury concentrations downstream of historic mining within the Carson River watershed.

    Science.gov (United States)

    Morway, Eric D; Thodal, Carl E; Marvin-DiPasquale, Mark

    2017-10-01

    The Carson River is a vital water resource for local municipalities and migratory birds travelling the Pacific Flyway. Historic mining practices that used mercury (Hg) to extract gold from Comstock Lode ore has left much of the river system heavily contaminated with Hg, a practice that continues in many parts of the world today. Between 1998 and 2013, the United States Geological Survey (USGS) collected and analyzed Carson River water for Hg and methylmercury (MeHg) concentrations resulting in a sixteen year record of unfiltered total mercury (uf.THg), filtered (dissolved) Hg (f.THg), total methylmercury (uf.MeHg), filtered MeHg (f.MeHg), and particulate-bound THg (p.THg) and MeHg (p.MeHg) concentrations. This represents one of the longest continuous records of Hg speciation data for any riverine system, thereby providing a unique opportunity to evaluate long-term trends in concentrations and annual loads. During the period of analysis, uf.THg concentration and load trended downward at rates of -0.85% and -1.8% per year, respectively. Conversely, the f.THg concentration increased at a rate of 1.7% per year between 1998 and 2005, and 4.9% per year between 2005 and 2013. Trends in flow-normalized partition coefficients for both Hg and MeHg suggest a statistically significant shift from the particulate to the filtered phase. The upwardly accelerating f.THg concentration and observed shift from the solid phase to the aqueous phase among the pools of Hg and MeHg within the river water column signals an increased risk of deteriorating ecological conditions in the lower basin with respect to Hg contamination. More broadly, the 16-year trend analysis, completed 140 years after the commencement of major Hg releases to the Carson River, provides a poignant example of the ongoing legacy left behind by gold and silver mining techniques that relied on Hg amalgamation, and a cautionary tale for regions still pursuing the practice in other countries. Published by Elsevier Ltd.

  7. Long-term effects of fire frequency and season on herbaceous vegetation in savannas of the Kruger National Park, South Africa

    CSIR Research Space (South Africa)

    Smith, MD

    2012-05-01

    Full Text Available in savannas, the experimental burn plots (EBPs), which is located in the Kruger National Park (South Africa) and encompasses four major savanna vegetation types that span broad spatial gradients of rainfall (450–700mm) and soil fertility....

  8. Long-term patterns of air temperatures, daily temperature range, precipitation, grass-reference evapotranspiration and aridity index in the USA Great Plains: Part I. Spatial trends

    Science.gov (United States)

    Kukal, M.; Irmak, S.

    2016-11-01

    Due to their substantial spatio-temporal behavior, long-term quantification and analyses of important hydrological variables are essential for practical applications in water resources planning, evaluating the water use of agricultural crop production and quantifying crop evapotranspiration patterns and irrigation management vs. hydrologic balance relationships. Observed data at over 800 sites across the Great Plains of USA, comprising of 9 states and 2,307,410 km2 of surface area, which is about 30% of the terrestrial area of the USA, were used to quantify and map large-scale and long-term (1968-2013) spatial trends of air temperatures, daily temperature range (DTR), precipitation, grass-reference evapotranspiration (ETo) and aridity index (AI) at monthly, growing season and annual time steps. Air temperatures had a strong north to south increasing trend, with annual average varying from -1 to 24 °C, and growing season average temperature varying from 8 to 30 °C. DTR gradually decreased from western to eastern parts of the region, with a regional annual and growing season averages of 14.25 °C and 14.79 °C, respectively. Precipitation had a gradual shift towards higher magnitudes from west to east, with the average annual and growing season (May-September) precipitation ranging from 163 to 1486 mm and from 98 to 746 mm, respectively. ETo had a southwest-northeast decreasing trend, with regional annual and growing season averages of 1297 mm and 823 mm, respectively. AI increased from west to east, indicating higher humidity (less arid) towards the east, with regional annual and growing season averages of 0.49 and 0.44, respectively. The spatial datasets and maps for these important climate variables can serve as valuable background for climate change and hydrologic studies in the Great Plains region. Through identification of priority areas from the developed maps, efforts of the concerned personnel and agencies and resources can be diverted towards development

  9. Trends in Short- and Long-Term Outcomes for Takotsubo Cardiomyopathy Among Medicare Fee-for-Service Beneficiaries, 2007 to 2012.

    Science.gov (United States)

    Murugiah, Karthik; Wang, Yun; Desai, Nihar R; Spatz, Erica S; Nuti, Sudhakar V; Dreyer, Rachel P; Krumholz, Harlan M

    2016-03-01

    The aim of this study was to assess trends in hospitalizations and outcomes for Takotsubo cardiomyopathy (TTC). There is a paucity of nationally representative data on trends in short- and long-term outcomes for patients with TTC. The authors examined hospitalization rates; in-hospital, 30-day, and 1-year mortality; and all-cause 30-day readmission for Medicare fee-for-service beneficiaries with principal and secondary diagnoses of TTC from 2007 to 2012. Hospitalizations for principal or secondary diagnosis of TTC increased from 5.7 per 100,000 person-years in 2007 to 17.4 in 2012 (p for trend < 0.001). Patients were predominantly women and of white race. For principal TTC, in-hospital, 30-day, and 1-year mortality was 1.3% (95% confidence interval [CI]: 1.1% to 1.6%), 2.5% (95% CI: 2.2% to 2.8%), and 6.9% (95% CI: 6.4% to 7.5%), and the 30-day readmission rate was 11.6% (95% CI: 10.9% to 12.3%). For secondary TTC, in-hospital, 30-day, and 1-year mortality was 3% (95% CI: 2.7% to 3.3%), 4.7% (95% CI: 4.4% to 5.1%), and 11.4% (95% CI: 10.8% to 11.9%), and the 30-day readmission rate was 15.8% (95% CI: 15.1% to 16.4%). Over time, there was no change in mortality or readmission rate for both cohorts. Patients ≥85 years of age had higher in-hospital, 30-day, and 1-year mortality and 30-day readmission rates. Among patients with principal TTC, male and nonwhite patients had higher 1-year mortality than their counterparts, whereas in those with secondary TTC, mortality was worse at all 3 time points. Nonwhite patients had higher 30-day readmission rates for both cohorts. Hospitalization rates for TTC are increasing, but short- and long-term outcomes have not changed. At 1 year, 14 in 15 patients with principal TTC and 8 in 9 with secondary TTC are alive. Older, male, and nonwhite patients have worse outcomes. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. Vegetative regeneration

    Science.gov (United States)

    George A. Schier; John R. Jones; Robert P. Winokur

    1985-01-01

    Aspen is noted for its ability to regenerate vegetatively by adventitious shoots or suckers that arise on its long lateral roots. It also produces sprouts from stumps and root collars; but they are not common. In a survey of regeneration after clearcutting mature aspen in Utah. Baker (1918b) found that 92% of the shoots originated from roots, 7% from root collars, and...

  11. Understory vegetation

    Science.gov (United States)

    Steve Sutherland; Todd F. Hutchinson; Jennifer L. Windus

    2003-01-01

    This chapter documents patterns of species composition and diversity within the understory vegetation layer and provides a species list for the four study areas in southern Ohio. Within each of 108 plots, we recorded the frequency of all vascular plant species in sixteen 2-m² quadrats. We recorded 297 species, including 187 forbs (176 perennials, 9 annuals, 2...

  12. Serving vegetables first: A strategy to increase vegetable consumption in elementary school cafeterias.

    Science.gov (United States)

    Elsbernd, S L; Reicks, M M; Mann, T L; Redden, J P; Mykerezi, E; Vickers, Z M

    2016-01-01

    Vegetable consumption in the United States is low despite the wealth of evidence that vegetables play an important role in reducing risk of various chronic diseases. Because eating patterns developed in childhood continue through adulthood, we need to form healthy eating habits in children. The objective of this study was to determine if offering vegetables before other meal components would increase the overall consumption of vegetables at school lunch. We served kindergarten through fifth-grade students a small portion (26-33 g) of a raw vegetable (red and yellow bell peppers) while they waited in line to receive the rest of their lunch meal. They then had the options to take more of the bell peppers, a different vegetable, or no vegetable from the lunch line. We measured the amount of each vegetable consumed by each child. Serving vegetables first greatly increased the number of students eating vegetables. On intervention days most of the vegetables consumed came from the vegetables-first portions. Total vegetable intake per student eating lunch was low because most students chose to not eat vegetables, but the intervention significantly increased this value. Serving vegetables first is a viable strategy to increase vegetable consumption in elementary schools. Long-term implementation of this strategy may have an important impact on healthy eating habits, vegetable consumption, and the health consequences of vegetable intake. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Observational Quantification of Climatic and Human Influences on Vegetation Greening in China

    Directory of Open Access Journals (Sweden)

    Wenjian Hua

    2017-04-01

    Full Text Available This study attempts to quantify the relative contributions of vegetation greening in China due to climatic and human influences from multiple observational datasets. Satellite measured vegetation greenness, Normalized Difference Vegetation Index (NDVI, and relevant climate, land cover, and socioeconomic data since 1982 are analyzed using a multiple linear regression (MLR method. A statistically significant positive trend of average growing-season (April–October NDVI is found over more than 34% of the vegetated areas, mainly in North China, while significant decreases in NDVI are only seen in less than 5% of the areas. The relationships between vegetation and climate (temperature, precipitation, and radiation vary by geographical location and vegetation type. We estimate the NDVI changes in association with the non-climatic effects by removing the climatic effects from the original NDVI time series using the MLR analysis. Our results indicate that land use change is the dominant factor driving the long-term changes in vegetation greenness. The significant greening in North China is due to the increase in crops, grasslands, and forests. The socioeconomic datasets provide consistent and supportive results for the non-climatic effects at the provincial level that afforestation and reduced fire events generally have a major contribution. This study provides a basis for quantifying the non-climatic effects due to possible human influences on the vegetation greening in China.

  14. The Climate-Population Nexus in the East African Horn: Emerging Degradation Trends in Rangeland and Pastoral Livelihood Zones

    Science.gov (United States)

    Pricope, N. G.; Husak, G. J.; Funk, C. C.; Lopez-Carr, D.

    2014-12-01

    Increasing climate variability and extreme weather conditions along with declining trends in both rainfall and temperature represent major risk factors affecting agricultural production and food security in many regions of the world. We identify regions where significant rainfall decrease from 1979-2011 over the entire continent of Africa couples with significant human population density increase. The rangelands of Ethiopia, Kenya, and Somalia in the East African Horn remain one of the world's most food insecure regions, yet have significantly increasing human populations predominantly dependent on pastoralist and agro-pastoralist livelihoods. Vegetation in this region is characterized by a variable mosaic of land covers, generally dominated by grasslands necessary for agro-pastoralism, interspersed by woody vegetation. Recent assessments indicate that widespread degradation is occurring, adversely impacting fragile ecosystems and human livelihoods. Using two underutilized MODIS products, we observe significant changes in vegetation patterns and productivity over the last decade all across the East African Horn. We observe significant vegetation browning trends in areas experiencing drying precipitation trends in addition to increasing population pressures. We also found that the drying precipitation trends only partially statistically explain the vegetation browning trends, further indicating that other factors such as population pressures and land use changes are responsible for the observed declining vegetation health. Furthermore, we show that the general vegetation browning trends persist even during years with normal rainfall conditions such as 2012, indicating potential long-term degradation of rangelands on which approximately 10 million people depend. These findings have serious implications for current and future regional food security monitoring and forecasting as well as for mitigation and adaptation strategies in a region where population is expected

  15. Understanding long-term (1982-2013) patterns and trends in winter wheat spring green-up date over the North China Plain

    Science.gov (United States)

    Wang, Sisi; Mo, Xingguo; Liu, Zhengjia; Baig, Muhammad Hasan Ali; Chi, Wenfeng

    2017-05-01

    Monitoring the spring green-up date (GUD) has grown in importance for crop management and food security. However, most satellite-based GUD models are associated with a high degree of uncertainty when applied to croplands. In this study, we introduced an improved GUD algorithm to extract GUD data for 32 years (1982-2013) for the winter wheat croplands on the North China Plain (NCP), using the third-generation normalized difference vegetation index form Global Inventory Modeling and Mapping Studies (GIMMS3g NDVI). The spatial and temporal variations in GUD with the effects of the pre-season climate and soil moisture conditions on GUD were comprehensively investigated. Our results showed that a higher correlation coefficient (r = 0.44, p the improved algorithm relative to GUD from the MCD12Q2 phenology product. In spatial terms, GUD increased from the southwest (less than day of year (DOY) 60) to the northeast (more than DOY 90) of the NCP, which corresponded to spatial reductions in temperature and precipitation. GUD advanced in most (78%) of the winter wheat area on the NCP, with significant advances in 37.8% of the area (p the interannual scale, the average GUD advanced from DOY 76.9 in the 1980s (average 1982-1989) to DOY 73.2 in the 1990s (average 1991-1999), and to DOY 70.3 after 2000 (average 2000-2013), indicating an average advance of 1.8 days/decade (r = 0.35, p the pre-season temperature, our findings underline that the effect of the pre-season soil moisture on GUD should also be considered. The improved GUD algorithm and satellite-based long-term GUD data are helpful for improving the representation of GUD in terrestrial ecosystem models and enhancing crop management efficiency.

  16. An initial investigation of the long-term trends in the fluxgate magnetometer (FGM) calibration parameters on the four Cluster spacecraft

    Science.gov (United States)

    Alconcel, L. N. S.; Fox, P.; Brown, P.; Oddy, T. M.; Lucek, E. L.; Carr, C. M.

    2014-07-01

    Over the course of more than 10 years in operation, the calibration parameters of the outboard fluxgate magnetometer (FGM) sensors on the four Cluster spacecraft are shown to be remarkably stable. The parameters are refined on the ground during the rigorous FGM calibration process performed for the Cluster Active Archive (CAA). Fluctuations in some parameters show some correlation with trends in the sensor temperature (orbit position). The parameters, particularly the offsets, of the spacecraft 1 (C1) sensor have undergone more long-term drift than those of the other spacecraft (C2, C3 and C4) sensors. Some potentially anomalous calibration parameters have been identified and will require further investigation in future. However, the observed long-term stability demonstrated in this initial study gives confidence in the accuracy of the Cluster magnetic field data. For the most sensitive ranges of the FGM instrument, the offset drift is typically 0.2 nT per year in each sensor on C1 and negligible on C2, C3 and C4.

  17. Long-term trends of changes in pine and oak foliar nitrogen metabolism in response to chronic nitrogen amendments at Harvard Forest, MA.

    Science.gov (United States)

    Minocha, Rakesh; Turlapati, Swathi A; Long, Stephanie; McDowell, William H; Minocha, Subhash C

    2015-08-01

    We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements were analyzed for control, low N (LN, 50 kg NH4NO3 ha(-1) year(-1)) and high N (HN, 150 kg NH4NO3 ha(-1) year(-1)) treatments. In the pine stands, partitioning of excess N into foliar PAs and AAs increased with both N treatments until 2002. By 2005, several of these effects on N metabolites disappeared for HN, and by 2008 they were mostly observed for LN plot. A significant decline in foliar Ca and P was observed mostly with HN for a few years until 2005. However, sapwood data actually showed an increase in Ca, Mg and Mn and no change in PAs in the HN plot for 2008, while AAs data revealed trends that were generally similar to foliage for 2008. Concomitant with these changes, mortality data revealed a large number of dead trees in HN pine plots by 2002; the mortality rate started to decline by 2005. Oak trees in the hardwood plot did not exhibit any major changes in PAs, AAs, nutrients and mortality rate with LN treatment, indicating that oak trees were able to tolerate the yearly doses of 50 kg NH4NO3 ha(-1) year(-1). However, HN trees suffered from physiological and nutritional stress along with increased mortality in 2008. In this case also, foliar data were supported by the sapwood data. Overall, both low and high N applications resulted in greater physiological stress to the pine trees than the oaks. In general, the time course of changes in metabolic data are in agreement with the published reports on changes in soil chemistry and microbial community structure, rates of soil carbon sequestration and production of woody biomass for this chronic N study. This correspondence of selected metabolites

  18. Trend of head circumference as a predictor of microcephaly among term infants born at a regional center in Malaysia between 2011-2015

    Directory of Open Access Journals (Sweden)

    Sutan R

    2018-01-01

    Full Text Available Rosnah Sutan,1 May Luu Yeong,1 Zaleha Abdullah Mahdy,2 Ahmad Shuhaila,2 Jaafar Rohana,3 Shareena Ishak,3 Khadijah Shamsuddin,1 Aniza Ismail,1 Idayu Badillah Idris,1 Saperi Sulong4 1Department of Community Health, 2Department of Obstetrics and Gynecology, 3Department of Pediatrics, 4Department of Medical Records, Universiti Kebangsaan Malaysia Medical Center, Kuala Lumpur, Malaysia Introduction: The aim of this study was to determine the trend of head circumference as predictor of microcephaly among term infants born in a teaching hospital in Malaysia from 2011 to 2015. Methodology: This was a cross-sectional study using data from the electronic birth census. The independent variables were mothers’ age and height, parity, birth weight and birth length. All term newborns, both alive and stillbirth, with 37–41 completed gestational weeks, and a birth weight of at least 500 g was extracted from the census. Results: A total of 26,503 newborns fulfilled the inclusion criteria (13,655 males, 12,840 females. The mean head circumferences for male and female newborns were 32.93 cm (± SD 1.32 and 32.56 cm (± SD 1.31. The average head circumference for Malaysian newborns was found to be smaller than the World Health Organization Standard Growth Chart for Term Infant. A total of 17.6% (n=4,669 of the total samples were observed to have microcephaly. Among them, 73.2% (n=3,419 were non-proportionate microcephaly with normal birth weight of 2.5kg and above. Bivariate analyses showed that all independent variables were significant predictors of microcephaly. Both simple and multiple logistic regressions demonstrated that low birth weight was the most significant predictors for microcephaly (adjusted OR 12.14, 95% CI 10.80, 13.65. Conclusion: There is an increasing trend of microcephaly across the years and the low birth weight was noted as the main predictor of microcephaly. Future studies are needed to determine the possible cause of increasing

  19. A comparative study of ancient sedimentary DNA, pollen and macrofossils from permafrost sediments of northern Siberia reveals long-term vegetational stability

    DEFF Research Database (Denmark)

    Jørgensen, Tina; Haile, James Seymour; Möller, Per

    2012-01-01

    and the determination of indicator species to describe environmental changes. Combining data from all three proxies reveals an area continually dominated by a mosaic vegetation of tundra-steppe, pioneer and wet-indicator plants. Such vegetational stability is unexpected, given the severe climate changes taking place...... in the Northern Hemisphere during this time, with changes in average annual temperatures of >22 °C. This may explain the abundance of ice-age mammals such as horse and bison in Taymyr Peninsula during the Pleistocene and why it acted as a refugium for the last mainland woolly mammoth. Our finding reveals...... the benefits of combining sedaDNA, pollen and macrofossil for palaeovegetational reconstruction and adds to the increasing evidence suggesting large areas of the Northern Hemisphere remained ecologically stable during the Late Pleistocene....

  20. Long-term trends of surface ozone and its influencing factors at the Mt Waliguan GAW station, China - Part 2: The roles of anthropogenic emissions and climate variability

    Science.gov (United States)

    Xu, Wanyun; Xu, Xiaobin; Lin, Meiyun; Lin, Weili; Tarasick, David; Tang, Jie; Ma, Jianzhong; Zheng, Xiangdong

    2018-01-01

    Inter-annual variability and long-term trends in tropospheric ozone are both environmental and climate concerns. Ozone measured at Mt Waliguan Observatory (WLG, 3816 m a.s.l.) on the Tibetan Plateau over the period of 1994-2013 has increased significantly by 0.2-0.3 ppbv yr-1 during spring and autumn but shows a much smaller trend in winter and no significant trend in summer. Here we explore the factors driving the observed ozone changes at WLG using backward trajectory analysis, chemistry-climate model hindcast simulations (GFDL AM3), a trajectory-mapped ozonesonde data set, and several climate indices. A stratospheric ozone tracer implemented in GFDL AM3 indicates that stratosphere-to-troposphere transport (STT) can explain ˜ 60 % of the simulated springtime ozone increase at WLG, consistent with an increase in the NW air-mass frequency inferred from the trajectory analysis. Enhanced STT associated with the strengthening of the mid-latitude jet stream contributes to the observed high ozone anomalies at WLG during the springs of 1999 and 2012. During autumn, observations at WLG are more heavily influenced by polluted air masses originating from South East Asia than in the other seasons. Rising Asian anthropogenic emissions of ozone precursors are the key driver of increasing autumnal ozone observed at WLG, as supported by the GFDL AM3 model with time-varying emissions, which captures the observed ozone increase (0.26 ± 0.11 ppbv yr-1). AM3 simulates a greater ozone increase of 0.38 ± 0.11 ppbv yr-1 at WLG in autumn under conditions with strong transport from South East Asia and shows no significant ozone trend in autumn when anthropogenic emissions are held constant in time. During summer, WLG is mostly influenced by easterly air masses, but these trajectories do not extend to the polluted regions of eastern China and have decreased significantly over the last 2 decades, which likely explains why summertime ozone measured at WLG shows no significant trend

  1. The long-term spatial-temporal trends and burden of esophageal cancer in one high-risk area: A population-registered study in Feicheng, China.

    Directory of Open Access Journals (Sweden)

    Xiubin Sun

    Full Text Available Feicheng County is a high-risk area for esophageal cancer in Shandong province, China. It is important to determine the long-term spatio-temporal trends in epidemiological characteristics and the burden of esophageal cancer, especially since the implementation of the national esophageal cancer screening program for early detection and treatment in 2005.The data collected in Feicheng County from 2001 to 2012 was extracted from the whole-population cancer registry system. The incidence, mortality, disability-adjusted life years (DALY and changing trends in esophageal cancer according to age and sex were calculated and described.The incidence rate of esophageal cancer in Feicheng was consistently high, and increased significantly for male, but not for female from 2001 to 2012, according to the joinpoint regression analysis. The highest and lowest yearly crude incidence rates were 160.78 and 95.97 per 100000 for males, and 81.36 and 52.17 per 100000 for females. The highest and lowest crude yearly mortality rates were 122.26 and 94.40 per 100000 for males, and 60.75 and 49.35 per 100000for females. Esophageal squamous cell carcinoma was the main pathology type and the tumor location changed significantly from 2001 to 2012. Overall, the DALY remained roughly stable and was estimated as 11.50 for males and 4.90 for females per 1000 people. The burden was mainly caused by premature death. There is an obvious spatial pattern in the distribution of incidence density and burden.Esophageal cancer remains a public health issue in Feicheng County with a high incidence, mortality and disease burden. The incidence and burden have obvious spatial heterogeneity, and further studies should be conducted to identify geographical risk factors for precise local prevention and control measures.

  2. componente vegetal

    Directory of Open Access Journals (Sweden)

    Fabio Moscovich

    2005-01-01

    Full Text Available In order to determine environmental impact, indicators based on vegetation characteristics that would generate the forestry monoculture with the adjacent native forest, 32 sample unit were installed in an area of LIPSIA private enterprise, Esperanza Department, Misiones with those characteristics. The plots of 100 m2 were distributed systematically every 25 meters. The vegetation was divided in stratum: superior (DBH ≥ 10 cm, middle (1,6 cm ≤ DBH > 10 cm and inferior (DBH< cm. There were installed 10 plots in a logged native forest, 10 plots in a 18 years old Pinus elliottii Engelm. with approximately 400 trees/ha., 6 plots in a 10 – 25 years old Araucaria angustifolia (Bertd. Kuntze limiting area with approximately 900 trees/ha., and 6 plots located in this plantation. In the studied area were identified 150 vegetation species. In the inferior stratum there were found differences as function of various floristic diversity indexes. In all the cases the native forest showed larger diversity than plantations, followed by Pinus elliottii, Araucaria plantation and Araucaria limiting area. All the studied forest fitted to a logarithmical series of species distributions, that would indicate the incidence of a environmental factor in this distribution.

  3. Beyond DAPA and DACA: Revisiting Legislative Reform in Light of Long-Term Trends in Unauthorized Immigration to the United States

    Directory of Open Access Journals (Sweden)

    Robert Warren

    2015-02-01

    exceeded the number who entered across the southern land border without inspection (EWIs in each year from 2008 to 2012.While the CMS estimates are based on sample data and assumptions that are subject to error, these trends are consistent with the best empirical information available.In November 2014 the Obama Administration announced an unprecedented set of executive action initiatives. At this writing, the Deferred Action for Parental Accountability (DAPA program and the expanded Deferred Action for Childhood Arrivals (DACA program, which would provide work authorization and temporary reprieve from removal to eligible persons, have been preliminarily enjoined. The temporary injunction, which the US Department of Justice plans to appeal to the Fifth Circuit Court of Appeals, comes in response to a legal challenge to the two programs by 26 states under Article II, section 3 of the US Constitution which requires the president to “take Care that the Laws be faithfully executed,” and under the Administrative Procedure Act (APA. In addition, the Republican majorities of the 114th Congress have vowed to prevent the implementation of these programs. However, the administration has expressed confidence that it will ultimately prevail in court and in its battle with Congress over these programs. Meanwhile, nongovernmental organizations (NGOs, community-based organizations (CBOs, and others continue to plan intensively for the DAPA and DACA programs, as well as for other executive action initiatives.This paper provides estimates of those who are potentially eligible for DAPA and DACA. However, it also looks beyond DAPA and DACA to make the case for broad legislative reform in light of long-term trends in unauthorized migration to the United States and the unauthorized resident population. In particular, it argues that substantial declines in the unauthorized population—a goal shared by partisans on both sides of the immigration debate—will require reform of the legal

  4. Long-term changes in the flora and vegetation of Lake Mikołajskie (Poland as a result of its eutrophication

    Directory of Open Access Journals (Sweden)

    Barbara Solińska-Górnicka

    2014-01-01

    Full Text Available Changes in littoral flora as well as aquatic and swamp vegetation were analysed with increasing eutrophication of the mesotrophic Lake Mikołajskie. Over 30 years the habitat conditions of the lake deteriorated and the phy-tolittoral was reduced from a zone 6 metres wide to one of only 2 metres. In addition, the number of submerged macrophyte species decreased by 50% and the frequency of most of the remaining species declined severalfold. No new species were encountered. Species retreating from the lake littoral included all Chara species, Potamogeton obtusifolius, P. natans and Hydrocharis morsus-ranae. A significant lowering of the phytosociological diversity and species richness of aquatic and swamp communities was observed. By 1994, six of the 12 associations identified in 1964 and representing the submerged and floating-leaved vegetation (e.g. Nitellopsidetum ubtusae, Charetum asperae and Potamogetonetum compressi were no longer present. In turn, 6 swamp communities from among the original 14 identified in the lake were lacking (e.g. Typhetum angustifoliae, Sugittario-Sparganietum emersi and Eleocharitetum palustris. At the same time, two new aquatic and swamp communities appeared (Ranunculetum circinuti, Myriophylletum spicati, Caricetum acutiformis and Caricetum distichae. In contrast there was an increase in the species richness of reedswamp communities due to an influx of marshland species. While the 1990s witnessed a distinct decrease in concentrations of nutrients in Lake Mikołajskie, the consequent increase in water transparency was not associated with an increase in the area of submerged macrophytes, or the species richness of aquatic vegetation.

  5. Spatial relationship between climatologies and changes in global vegetation activity

    NARCIS (Netherlands)

    Jong, de R.; Schaepman, M.E.; Furrer, R.; Bruin, de S.; Verburg, P.H.

    2013-01-01

    Vegetation forms a main component of the terrestrial biosphere and plays a crucial role in land-cover and climate-related studies. Activity of vegetation systems is commonly quantified using remotely sensed vegetation indices (VI). Extensive reports on temporal trends over the past decades in time

  6. A comparison of the isotopic composition of lead in rainwater, surface vegetation and tree bark at the long-term monitoring site, Glensaugh, Scotland, in 2007

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, John G., E-mail: J.G.Farmer@ed.ac.uk [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Eades, Lorna J. [School of Chemistry, University of Edinburgh, Edinburgh EH9 3JJ, Scotland (United Kingdom); Graham, Margaret C.; Cloy, Joanna M. [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Bacon, Jeffrey R. [The Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland (United Kingdom)

    2010-08-01

    The lead concentrations and isotopic ratios ({sup 206}Pb/{sup 207}Pb, {sup 208}Pb/{sup 206}Pb, {sup 208}Pb/{sup 207}Pb) of 31 rainwater (September 2006-December 2007) and 11 surface vegetation (moss, lichen, heather) samples (October 2007) from the rural upland catchment of Glensaugh in northeast Scotland and of nine bark samples (October 2007) from trees, predominantly Scots pine, in or near Glensaugh were determined. The mean {sup 206}Pb/{sup 207}Pb ratios for rainwater in 2006 and 2007 were similar to those previously determined for 2000 to 2003 at Glensaugh, yielding an average mean annual value of 1.151 {+-} 0.005 ({+-} 1 SD) for the period from 2000, when an outright ban on leaded petrol came into force in the UK, to 2007. The mean {sup 206}Pb/{sup 207}Pb ratio (1.146 {+-} 0.004; n = 7) for surface vegetation near the top (430-450 m) of the catchment was not significantly different (Student's t test) from that of rainwater (1.148 {+-} 0.017; n = 24) collected over the 12-month period prior to vegetation sampling, but both were significantly different, at the 0.1% (i.e. p < 0.001) and 1% (p < 0.01) level, respectively, from the corresponding mean value (1.134 {+-} 0.006; n = 9) for the outermost layer of tree bark. When considered in conjunction with similar direct evidence for 2002 and indirect evidence (e.g. grass, atmospheric particulates, dated peat) for recent decades in the Glensaugh area, these findings confirm that the lead isotopic composition of surface vegetation, including that of suitably located moss, reflects that of the atmosphere while that of the outermost layer of Scots pine bark is affected by non-contemporaneous lead. The nature and relative extent of the different contributory sources of lead to the current UK atmosphere in the era of unleaded petrol, however, are presently not well characterised on the basis of lead isotopic measurements.

  7. Vegetation development and native species establishment in reclaimed coal mine lands in Alberta : directions for reclamation planning

    Energy Technology Data Exchange (ETDEWEB)

    Longman, P. [Calgary Univ., AB (Canada). Faculty of Environmental Design

    2010-07-01

    This paper discussed a study undertaken to evaluate reclamation vegetation at Coal Valley Mine in Alberta with respect to expected vegetation changes over time, establishing a successional model of vegetation development, and factors contributing to the observed patterns. Most of the expected vegetation trends were evident, including lower grass cover and height, lower legume cover, a higher degree of native plant species richness, and the establishment of woody species. Four vegetation communities (2 graminoid-dominated and 2 conifer-dominated) were identified in the study, for which a possible successional model was constructed. Vegetation dynamics for agronomic grasses, legumes, and tree cover were discussed. Areas with Lodgepole Pine were found to have higher species richness and cover. Concerns were raised that the identified trends may not in fact supply the expected opportunities for native species establishment. In order to facilitate the establishment of native species and better manage reclamation vegetation development, the author recommended that a conifer overstory be established to increase native richness and native cover, and that more appropriate seeding mixes be developed as certain agronomic species are detrimental to long-term goals. The author also recommended that site-specific seed mixes be developed according to end land-use goals, that a planting program for native plants and shrubs be developed, and that a monitoring program be established to better inform future reclamation efforts. The recommendations were designed to bring reclamation efforts into line with reclamation goals. 12 refs., 4 tabs., 2 figs.

  8. Persistent organic pollutants (POPs) in the atmosphere of coastal areas of the Ross Sea, Antarctica: Indications for long-term downward trends.

    Science.gov (United States)

    Pozo, Karla; Martellini, Tania; Corsolini, Simonetta; Harner, Tom; Estellano, Victor; Kukučka, Petr; Mulder, Marie D; Lammel, Gerhard; Cincinelli, Alessandra

    2017-07-01

    Passive air samplers were used to evaluate long-term trends and spatial distribution of trace organic compounds in Antarctica. Duplicate PUF disk samplers were deployed at six automatic weather stations in the coastal area of the Ross sea (East Antarctica), between December 2010 and January 2011, during the XXVI Italian Scientific Research Expedition. Among the investigated persistent organic compounds, Hexachlorobenzene was the most abundant, with air concentrations ranging from 0.8 to 50 pg m -3 . In general, the following decreasing concentration order was found for the air samples analyzed: HCB > PeCB > PCBs > DDTs > HCHs. While HCB concentrations were in the same range as those reported in the atmosphere of other Antarctic sampling areas and did not show a decline, HCHs and DDTs levels were lower or similar to those determined one or two decades ago. In general, the very low concentrations reflected the pristine state of the East Antarctica air. Backward trajectories indicated the prevalence of air masses coming from the Antarctic continent. Local contamination and volatilization from ice were suggested as potential sources for the presence of persistent organic pollutants in the atmosphere. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. The use of autecological and environmental parameters for establishing the status of lichen vegetation in a baseline study for a long-term monitoring survey

    International Nuclear Information System (INIS)

    Gombert, S.; Asta, J.; Seaward, M.R.D.

    2005-01-01

    In 1997 the ecological characteristics of the epiphytic species (83 lichens and two algae) of an urban area (Grenoble, France) were determined. Seven autecological indices were used to characterize the lichen ecology: illumination index, humidity index, pH of bark, nutrient status of substratum, ecological index of IAP and frequency. Six clusters (A1-A6) were defined using cluster analysis and principal component analysis. Seven environmental parameters characterizing the stations and the lichen releves were also used: elevation, parameters of artificiality (urbanization, traffic and local land use), IAP, and the percentage of nitrophytic and acidophytic species. Six clusters (B1-B6) were defined using cluster analysis and canonical correspondence analysis. Four clusters (C1-C4) were finally defined using an empirical integrated method combining the autecological and environmental parameters. This final clustering which established the status of the lichen vegetation in 1997 can be reliably used as a baseline study to effectively monitor environmental changes in this urban area. - Ecological clustering which establishes the status of lichen vegetation can be reliably used as a baseline study to monitor environmental changes

  10. Vegetable Genetic Resources in China

    Directory of Open Access Journals (Sweden)

    Haiping WANG

    2018-03-01

    Full Text Available China is recognized as an important region for plant biodiversity based on its vast and historical collection of vegetable germplasm. The aim of this review is to describe the exploration status of vegetable genetic resources in China, including their collection, preservation, evaluation, and utilization. China has established a number of national-level vegetable genetic resources preservation units, including the National Mid-term Genebank for Vegetable Germplasm Resources, the National Germplasm Repository for Vegetatively-Propagated Vegetables, and the National Germplasm Repository for Aquatic Vegetables. In 2015, at least 36 000 accessions were collected and preserved in these units. In the past decade, 44 descriptors and data standards for different species have been published, and most accessions have been evaluated for screening the germplasms for specific important traits such as morphological characteristics, disease resistance, pest resistance, and stress tolerance. Moreover, the genetic diversity and evolution of some vegetable germplasms have been evaluated at the molecular level. Recently, more than 1 000 accessions were distributed to researchers and breeders each year by various means for vegetable research and production. However, additional wild-relative and abroad germplasms from other regions need to be collected and preserved in the units to expand genetic diversity. Furthermore, there is a need to utilize advanced techniques to better understand the background and genetic diversity of a wide range of vegetable genetic resources. This review will provide agricultural scientists’ insights into the genetic diversity in China and provide information on the distribution and potential utilization of these valuable genetic resources. Keywords: vegetable, genetic resource, preservation, evaluation, utilization