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Sample records for vegetation types ecological

  1. Description of vegetation types

    US Fish and Wildlife Service, Department of the Interior — This document provides descriptions of five vegetation types found in Iowa- oak savannah, mature hardwoods, floodplain woods, scrub woods, and riparian woods. Oak...

  2. Next generation dynamic global vegetation models: learning from community ecology

    Scheiter, Simon; Higgins, Steven; Langan, Liam

    2013-04-01

    Dynamic global vegetation models are a powerful tool to project the past, current and future distribution of vegetation and associated water and carbon fluxes. However, most models are limited by how they define vegetation and by their simplistic representation of competition. We discuss how concepts from community assembly theory and coexistence theory can help to improve vegetation models. We further present a new trait- and individual-based dynamic vegetation model (the aDGVM2) that allows each individual plant to adopt a unique combination of trait values. These traits define how each individual plant grows and competes with other plants under given environmental conditions. The performance of individual plants in turn drives the assembly of a plant community. A genetic optimisation algorithm is used to simulate the inheritance of traits and different levels of reproductive isolation between individuals. Together these model properties allow the assembly of plant communities that are well adapted to a site's biotic and abiotic conditions. Simulated communities can be classified into different plant functional types or biome types by using trait data bases. We illustrate that the aDGVM2 can simulate (1) how environmental conditions and changes in these conditions influence the trait spectra of assembled plant communities, (2) that fire selects for traits that enhance fire protection and reduces trait diversity, and (3) the emergence of communities dominated by life history strategies that are suggestive of colonisation-competition trade-offs. The aDGVM2 deals with functional diversity and competition fundamentally differently from current dynamic vegetation models. We argue that this approach will yield novel insights as to how vegetation may respond to climate change and we believe that it could foster fruitful collaborations between research communities that focus on plant functional traits, plant competition, plant physiology, systems ecology and earth system

  3. Effect of ecological factors on the zonation of wetland vegetation

    Richard Hrivnák

    2011-04-01

    Full Text Available The influence of some ecological factors to aquatic and marsh vegetation was studied during 1998-2000. Three basic vegetation units (Caricetum buekii, Typhetum latifoliae and Ceratophylletum submersi and three transitional communities were defined in the belt transect, which was established along the moisture gradient. The content of available soil nutrients in individual vegetation types differed only in case of the Ceratophyllum submersum community, where a higher magnesium and nitrogen content accumulated due to specific environmental conditions. Water and marsh vegetation is usually characterised by a pronounced spatial and temporal dynamics. In the studied area, its zonation was dependent from the terrain morphology, and both depth and duration of floods. The fluctuation of ground and surface water table during a three-year period caused changes in the occurrence and cover of several species (e.g. Carex buekii, Typha latifolia, aquatic macrophytes. Pronounced changes in the cover of some species occurred even within a single vegetation season due to the long-term sink of water table below the ground surface.

  4. The vegetation of Yucca Mountain: Description and ecology

    NONE

    1996-03-29

    Vegetation at Yucca Mountain, Nevada, was monitored over a six-year period, from 1989 through 1994. Yucca Mountain is located at the northern limit of the Mojave Desert and is the only location being studied as a potential repository for high-level nuclear waste. Site characterization consists of a series of multidisciplinary, scientific investigations designed to provide detailed information necessary to assess the suitability of the Yucca Mountain Site as a repository. This vegetation description establishes a baseline for determining the ecological impact of site characterization activities; it porvides input for site characterization research and modeling; and it clarifies vegetation community dynamics and relationships to the physical environment. A companion study will describe the impact of site characterization of vegetation. Cover, density, production, and species composition of vascular plants were monitored at 48 Ecological Study Plots (ESPs) stratified in four vegetation associations. Precipitation, soil moisture, and maximum and minimum temperatures also were measured at each study plot.

  5. Vegetation Landscape, Ecological Characteristics and Soil Fixation for Riverbank in Taiwan

    CHANG Chunpin; LIN Farching; LIANG Taching; CHEN Yichang

    2007-01-01

    This study is aimed to investigate and analyze the vegetation landscape around Rivers of Hou-lung, Fa-tz, Da-li, Ching-shuei and Gau- ping, and to select the suitable plant species that could be applied for the area of riverbank ecological engineering in Taiwan. Studying the vegetation established the key point and procedure of ecological engineering in the riverside and revetment, to compile and edit the dominant plants' types, life form, propagating method, root systems' characteristics and functions for soil conservation. This research choses three dominant plants for roots strength test. The fitting models of plants pulling resistance(Rp', kg) between plant height (H, cm), diameter near ground (Dn,mm), diameter above ground 100 mm (Da, mm), The research finished the relative abundant, types and cluster analysis of riverbank dominant plants that generalize vegetative distribution and ecological restoration for different river types to apply and manage in Taiwan.

  6. The vegetation ecology of municipal Durban, Natal. Floristic classification

    D. C. Roberts

    1993-12-01

    Full Text Available The vegetation of municipal Durban is classified according to the Braun-Blanquet method, using the PHYTOTAB program package. Five major vegetation types with 18 communities are described, as are the major environmental factors influencing vegetation composition and structure.

  7. REPEATABILITY OF THE FRENCH HIGHER VEGETATION TYPES ACCORDING

    H. BRISSE

    1998-04-01

    Full Text Available Higher vegetation types are generally determined by successive approximations and defined by a common consent. Instead, they might be statistically determined and repeated, according to a numerical method called ‘socio-ecology’. This method deals only with floristical data, but gives them an ecological meaning by a previous calibration of the relations between plants, computed as ecological indices. It is applied to a pair of two homologous samples, each having 2.000 relevés and coming from the 60.000 relevés stored in the French data bank ‘Sophy’. Each sample covers the main ecological gradients of the bank, it defines a hierarchy of vegetation types and it explains half the peculiarity of a type with only 10 to 30 discriminant plants, out of the 5.000 plants observed in the relevés. Results : 1 The discriminant plants may characterize the vegetation types, including the higher ones, in a coherent and readable form. 2 In the two independent classifications, having different structures, the same vegetation types are repeated. They are the reciprocal nearest types, in the socio-ecological space. Though the two classifications have no one relevé in common, the repeated types have nearly the same discriminant plants. 3 At the highest level, two clear-cut main types show the difference between light and shadow. The same herbaceous discriminant plants, for a type, and the ligneous or sciaphilous ones, for the other, have similar fidelities and constancies in the two classifications. 4 Such a numerical agreement, instead of common consent, appears again in the sub-types, which remind the classical ones, but which are repeatable.

  8. Study on vegetation ecological water requirement in Ejina Oasis

    2007-01-01

    The Ecological Water Requirement (EWR) of desert oasis is the amount of water required to maintain a normal growth of vegetation in the special ecosystems. In this study EWR of the Ejina desert oasis is estimated through the relational equation between normalized difference vegetation index (NDVI), productivity and transpiration coefficient, which was established by a combination of the RS, GIS, GPS techniques with the field measurements of productivity. The results show that about 1.53×108 m3 water would be needed to maintain the present state of the Ejina Oasis, and the ecological water requirement would amount to 3.49×108 m3 if the existing vegetation was restored to the highest productivity level at present. Considering the domestic water requirement, river delivery loss, oasis vegetation water con-sumption, farmland water demand, precipitation recharge, etc., the draw-off discharge of the Heihe River (at Longxin Mount) should be 1.93×108―2.23 ×108 m3 to maintain the present state of the Ejina Oasis, and 4.28×108―5.17×108 m3 to make the existing vegetation be restored to the highest productiv-ity level at present.

  9. LANDFIRE (90m) Existing Vegetation Type

    U.S. Geological Survey, Department of the Interior — This map depicts the distribution of existing vegetation types contained in the LANDFIRE dataset. All 30-meter EVT grids were resampled to 90-meter grids and merged...

  10. The vegetation ecology of the Eastern Transvaal Escarpment in the Sabie area. 2. Floristic classification

    G. B. Deall

    1989-12-01

    Full Text Available The indigenous vegetation of the Eastern Transvaal Escarpment in the Sabie area is classified with the aid of the PHYTOTAB program package. Four ecological-formation classes (efc based on floristics. physiognomy and climate correspond to four data subsets. Plant communities in each efc are defined by means of 46 differential species-groups distributed amongst forest, thicket, woodland, shrubland and grassland structural types. Environmental correlation is facilitated by means of 21 habitat types.

  11. Vegetation Evolution with Degenerating Soil Ecology Under Unequal Competition

    LIN Zhen-Shan; QI Xiang-Zhen

    2004-01-01

    A vegetation evolution model influenced by a degeneration of soil ecological functions was set up. Three ideal communities of a) trees, b) shrubs, and c) herbage populations were first simulated. Then numerical simulations of the evolutionary and developmental processes of a natural forest community, which is composed of over 100 species,were conducted. Results of the study showed that a) in all communities, soil degeneration not only drove some weaker species to extinction, but also a few dominant ones; b) there were different response scales with species in an ideal tree metapopulation that could persist as long as a thousand years, with shrubs in an ideal shrub metapopulation that could persevere for several hundred years, and with species in an ideal herbage metapopulation that could become extinct within 10 years; and c) each metapopulation experienced three evolutionary stages during adaptation to the environment: a) the stage of compelled adaptation or resistance, b) the adjusted stage, and c) the stabilized stage.

  12. Application of GIS in Ecological Land Type (ELT) mapping——A case in Changbai Mountain area

    2002-01-01

    This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin Province), and expatiates the definition, basic characters and its development of Ecological Land Classification (ELC). Based on the combination of relief map, satellite photography for study area and vegetation inventory data of 480 sample sites, a 5-class and a 15-class ecological land type map was concluded according to 4 important factors including slope, aspect, vegetation and elevation. Ecological Classification System (ECS) is a method to identify, characterize, and map ecosystems. The Ecological Land Type (ELT) was examined and applied initially in eastern Jilin Province.

  13. Next generation dynamic global vegetation models: learning from community ecology (Invited)

    Scheiter, S.; Higgins, S.; Langan, L.

    2013-12-01

    Dynamic global vegetation models are a powerful tool to project past, current and future vegetation patterns and the associated biogeochemical cycles. However, most models are limited by their representation of vegetation by using static and pre-defined plant functional types and by their simplistic representation of competition. We discuss how concepts from community assembly theory and coexistence theory can help to improve dynamic vegetation models. We present a trait- and individual-based dynamic vegetation model, the aDGVM2, that allows individual plants to adopt a unique combination of trait values. These traits define how individual plants grow, compete and reproduce under the given biotic and abiotic conditions. A genetic optimization algorithm is used to simulate trait inheritance and reproductive isolation between individuals. These model properties allow the assembly of plant communities that are adapted to biotic and abiotic conditions. We show (1) that the aDGVM2 can simulate coarse vegetation patterns in Africa, (2) that changes in the environmental conditions and disturbances strongly influence trait diversity and the assembled plant communities by influencing traits such as leaf phenology and carbon allocation patterns of individual plants and (3) that communities do not necessarily return to the initial state when environmental conditions return to the initial state. The aDGVM2 deals with functional diversity and competition fundamentally differently from current models and allows novel insights as to how vegetation may respond to climate change. We believe that the aDGVM2 approach could foster collaborations between research communities that focus on functional plant ecology, plant competition, plant physiology and Earth system science.

  14. Mapping and characterizing the vegetation types of the Democratic Republic of Congo using SPOT VEGETATION time series

    Vancutsem, C.; Pekel, J.-F.; Evrard, C.; Malaisse, F.; Defourny, P.

    2009-02-01

    The need for quantitative and accurate information to characterize the state and evolution of vegetation types at a national scale is widely recognized. This type of information is crucial for the Democratic Republic of Congo, which contains the majority of the tropical forest cover of Central Africa and a large diversity of habitats. In spite of recent progress in earth observation capabilities, vegetation mapping and seasonality analysis in equatorial areas still represent an outstanding challenge owing to high cloud coverage and the extent and limited accessibility of the territory. On one hand, the use of coarse-resolution optical data is constrained by performance in the presence of cloud screening and by noise arising from the compositing process, which limits the spatial consistency of the composite and the temporal resolution. On the other hand, the use of high-resolution data suffers from heterogeneity of acquisition dates, images and interpretation from one scene to another. The objective of the present study was to propose and demonstrate a semi-automatic processing method for vegetation mapping and seasonality characterization based on temporal and spectral information from SPOT VEGETATION time series. A land cover map with 18 vegetation classes was produced using the proposed method that was fed by ecological knowledge gathered from botanists and reference documents. The floristic composition and physiognomy of each vegetation type are described using the Land Cover Classification System developed by the FAO. Moreover, the seasonality of each class is characterized on a monthly basis and the variation in different vegetation indicators is discussed from a phenological point of view. This mapping exercise delivers the first area estimates of seven different forest types, five different savannas characterized by specific seasonality behavior and two aquatic vegetation types. Finally, the result is compared to two recent land cover maps derived from

  15. Vegetation Classification, Ecological Integrity Assessment (EIA), Climate Change Vulnerability Assessment at Camas National Wildlife Refuge

    US Fish and Wildlife Service, Department of the Interior — This project includes a pilot study to map the vegetation of Camas National Wildlife Refuge and a report on the overall ecological integrity of the refuge, how it...

  16. Vegetation type classification and vegetation cover percentage estimation in urban green zone using pleiades imagery

    Trisakti, Bambang

    2017-01-01

    Open green space in the urban area has aims to maintain the availability of land as a water catchment area, creating aspects of urban planning through a balance between the natural environment and the built environment that are useful for the public needs. Local governments have to make the green zone plan map and monitor the green space changes in their territory. Medium and high resolution satellite imageries have been widely utilized to map and monitor the changes of vegetation cover as an indicator of green space area. This paper describes the use of pleaides imagery to classify vegetation types and estimate vegetation cover percentage in the green zone. Vegetation cover was mapped using a combination of NDVI and blue band. Furthermore, vegetation types in the green space were classified using unsupervised and supervised (ISODATA and MLEN) methods. Vegetation types in the study area were divided into sparse vegetation, low-medium vegetation and medium-high vegetation. The classification accuracies were 97.9% and 98.9% for unsupervised and supervised method respectively. The vegetation cover percentage was determined by calculating the ratio between the vegetation type area and the green zone area. These information are useful to support green zone management activities.

  17. NatureServe International Ecological Classification Standard: Terrestrial Ecological Classifications of Vegetation Alliances and Associations at Prime Hook National Wildlife Refuge

    US Fish and Wildlife Service, Department of the Interior — This subset of the International Ecological Classification Standard represents the National Vegetation Classification Standard (NVCS) and covers vegetation alliances...

  18. The integration of GPS, vegetation mapping and GIS in ecological and behavioural studies

    Steven Mark Rutter

    2007-07-01

    Full Text Available Global Positioning System (GPS satellite navigation receivers are increasingly being used in ecological and behavioural studies to track the movements of animals in relation to the environments in which they live and forage. Concurrent recording of the animal's foraging behaviour (e.g. from jaw movement recording allows foraging locations to be determined. By combining the animal GPS movement and foraging data with habitat and vegetation maps using a Geographical Information System (GIS it is possible to relate animal movement and foraging location to landscape and habitat features and vegetation types. This powerful approach is opening up new opportunities to study the spatial aspects of animal behaviour, especially foraging behaviour, with far greater precision and objectivity than before. Advances in GPS technology now mean that sub-metre precision systems can be used to track animals, extending the range of application of this technology from landscape and habitat scale to paddock and patch scale studies. As well as allowing ecological hypotheses to be empirically tested at the patch scale, the improvements in precision are also leading to the approach being increasing extended from large scale ecological studies to smaller (paddock scale agricultural studies. The use of sub-metre systems brings both new scientific opportunities and new technological challenges. For example, fitting all of the animals in a group with sub-metre precision GPS receivers allows their relative inter-individual distances to be precisely calculated, and their relative orientations can be derived from data from a digital compass fitted to each receiver. These data, analyzed using GIS, could give new insights into the social behaviour of animals. However, the improvements in precision with which the animals are being tracked also needs equivalent improvements in the precision with which habitat and vegetation are mapped. This needs some degree of automation, as

  19. FRUIT AND VEGETABLE CONSUMPTION BY ECOLOGICAL ZONE AND SOCIOECONOMIC STATUS IN GHANA.

    Amo-Adjei, Joshua; Kumi-Kyereme, Akwasi

    2015-09-01

    The disease burden in both developed and developing countries is moving towards higher proportions of chronic diseases, and diseases such as cancers are now considered to be of public health concern. In sub-Saharan Africa, healthy behaviours such as fruit and vegetable consumption are recommended to reduce the chances of onset of chronic diseases. This paper examines the determinants of fruit and vegetable consumption in Ghana with particular emphasis on consumption by ecological zone. Data were from the 2008 Ghana Demographic and Health Survey (n=4916 females; n=4568 males). Univariate and multivariate analyses were performed using basic descriptive and Poisson regression. The main independent variable was ecological zone and the dependent variables were levels of fruit and vegetable consumption. The mean number of fruits and vegetables consumed in a week was higher among females (fruits: 7.5, 95% CI=7.3-7.7; vegetables: 8.1, 95% CI=7.8-8.3) than males (fruits: 6.2, 95% CI=6.0-6.4; vegetables: 7.9, 95% CI=7.7-8.2). There were significant differences in consumption by ecological zone. Respondents in the Savannah zone consumed less fruit than those in the Coastal and Forest zones, but the differences in fruit and vegetable consumption between the Coastal and Savannah zones were not consistent, especially for vegetable consumption. The findings suggest that one of the key interventions to improve fruit and vegetable consumption could lie in improving distribution systems since their consumption is significantly higher in the Forest zone, where the production of fruit and vegetables is more developed than in the Savannah and Coastal zones. The findings relating to household wealth challenge conventional knowledge on fruit and vegetable consumption, and rather argue for equal consideration of spatial differences in critical health outcomes.

  20. Differences in hydrological responses for different vegetation types on a steep slope on the Loess Plateau, China

    Duan, Liangxia; Huang, Mingbin; Zhang, Luodan

    2016-06-01

    Extensive vegetation restoration practices have been implemented to control soil erosion on the Loess Plateau, China. However, no strict guidelines are available to determine the most suitable plant species for vegetation restoration within a given area. The objective of this study was to quantify the changes of each component (soil water storage, surface runoff, and actual evapotranspiration) of a water balance model and soil loss over time under eight different vegetation types, and to further determine the optimal vegetation type for soil and water conservation and sustainable ecological restoration on the steep slopes (>25°) on the Loess Plateau. The results indicated that vegetation type substantially affected soil water storage and that the greatest soil water storage in both the shallow (0-2 m) and the deep soil layers (2-5 m) occurred under Bothriochloa ischaemum L. (BOI). Vegetation type also affected surface runoff and soil losses. The most effective vegetation types for reducing soil erosion were BOI and Sea-buckthorn (Hippophae rhamnoides L.), while Chinese pine (Pinus tabulaeformis Carr.) and Chinese pine + Black locust (Robinia pseudoacacia L.) were the most ineffective types. Soil water dynamics and evapotranspiration varied considerably among the different vegetation types. A soil water surplus was only found under BOI, while insufficient water replenishment existed under the other seven vegetation types. The higher water consumption rates of the seven vegetation types could result in soil desiccation, which could lead to severe water stresses that would adversely affect plant growth. This study suggested that both vegetation type and its effect on controlling soil erosion should be considered when implementing vegetation restoration and that BOI should be highly recommended for vegetation restoration on the steep slopes of the Loess Plateau. A similar approach to the one used in this study could be applied to other regions of the world confronted

  1. [Remote sensing based monitoring of vegetation dynamics and ecological restoration in Beijing mountainous area].

    Hu, Yong; Liu, Liang-yun; Jia, Jian-hua

    2010-11-01

    By using the Landsat images in 1979, 1988, 1999, 2005, and 2009, and the linear unmixed model at pixel scale, this paper analyzed the spatiotemporal variation of vegetation coverage in Beijing mountainous area. After detecting the areas of vegetation degradation or restoration, the impacts of elevation, slope, and soil type on vegetation restoration were studied. From 1979 to 1988, the vegetation coverage in the study area had no obvious change, but in the following 12 years, the vegetation coverage was seriously destroyed due to the fast development of social economy. Fortunately, many protective measures were taken since 2000, which improved the vegetation coverage to 72% in 2009, with an increment of 13% compared to the vegetation coverage in 1999. A significant correlation was observed between the variations of vegetation coverage and territorial features. The areas with poor soil or large slope were more easily suffered from degradation than other places, and the flat regions with low elevation were more affected by human activities.

  2. Ecological optimality in water-limited natural soil-vegetation systems. I - Theory and hypothesis

    Eagleson, P. S.

    1982-01-01

    The solution space of an approximate statistical-dynamic model of the average annual water balance is explored with respect to the hydrologic parameters of both soil and vegetation. Within the accuracy of this model it is shown that water-limited natural vegetation systems are in stable equilibrium with their climatic and pedologic environments when the canopy density and species act to minimize average water demand stress. Theory shows a climatic limit to this equilibrium above which it is hypothesized that ecological pressure is toward maximization of biomass productivity. It is further hypothesized that natural soil-vegetation systems will develop gradually and synergistically, through vegetation-induced changes in soil structure, toward a set of hydraulic soil properties for which the minimum stress canopy density of a given species is maximum in a given climate. Using these hypotheses, only the soil effective porosity need be known to determine the optimum soil and vegetation parameters in a given climate.

  3. Vegetation relevés and soil measurements in the Netherlands: the Ecological Conditions Database (EC)

    Wamelink, G.W.W.; Adrichem, van M.H.C.; Dobben, van H.F.; Frissel, J.Y.; Held, den M.E.; Joosten, V.; Malinowska, A.H.; Slim, P.A.; Wegman, R.M.A.

    2012-01-01

    Since its establishment around 1990, the Ecological Conditions Database (EC; GIVD ID EU-00-006) has been accumulating vegetation relevés from the Netherlands, each accompanied by at least one abiotic soil measurement (e.g. pH or nutrient availability). On 1-1-2010, the database contained 8,229 relev

  4. Ecological and Economic Benefits of Vegetation Management Measures in Citrus Orchards on Red Soils

    SHUI Jian-Guo; WANG Qiu-Zhen; LIAO Gen-Qing; J.AU; J.L.ALLARD

    2008-01-01

    A three-year experiment was conducted to investigate and compare the economic and ecological benefits of six types of vegetation management measures in citrus orchards of the hilly red soil region of the eastern part of China.Six vegetation treatments,including tillage without herbicide (clean tillage) and no tillage without herbicide (sod culture)and with herbicide paraquat (paraquat),glyphosate (glyphosate),glyphosate-glyphosate-paraquat (G-G-P),and paraquatparaquat-glyphosate (P-P-G),were applied in the citrus orchards on a clayey red soil with slopes of 8° and 13° and a sandy soil with slope of 25°.The results showed that the sod culture,paraquat,glyphosate,G-G-P,and P-P-G treatments reduced surface runoff by 38.8%,42.5%,18.7%,28.7%,and 37.5%,then the soil-water losses by 55.5%,51.7%,39.9%,46.8%,and 50.0%,and the N,P,and K nutrient losses by 60.3%,50.2%,37.0%,41.8%,and 45.4%,respectively,as compared with the clean tillage treatment.The weed regeneration ratios with the treatments of clean tillage without herbicide,paraquat,glyphosate,G-G-P,and P-P-G were reduced by 55.1%,67.2%,30.3%,36.8%,and 51.2%,respectively,as compared withthe sod culture.The sod culture,paraquat,glyphosate,G-G-P,and P-P-G treatments could increase the soil fertility (annual accumulation of N,P,K,and OM) by 7.1%,6.9%,5.3%,6.2%,and 6.6%,respectively,whereas the clean tillage treatment without herbicide reduced soil fertility by 4.4% after the three-year experiment.The citrus fruit yields in the treatments of paraquat,glyphosate,G-G-P,and P-P-G increased by 7%-10%;the soluble solid,total sugar,total acidity,sugar-acid ratio,and single fruit weight of citrus fruits of all treatments except sod culture significantly (P > 0.05)exceeded that of the clean tillage treatment.In general,the paraquat treatment showed the best economic and ecological benefits among the six treatments;therefore,it could be regarded as the best available vegetation management measure in citrus orchards of hilly red

  5. Palaeo plant diversity in subtropical Africa – ecological assessment of a conceptual model of climate–vegetation interaction

    V. P. Groner

    2015-07-01

    Full Text Available We here critically re-assess a conceptual model dealing with the potential effect of plant diversity on climate–vegetation feedback, and provide an improved version adjusted to plant types that prevailed during the African Humid Period (AHP. Our work contributes to the understanding of the timing and abruptness of vegetation decline at the end of the AHP, investigated by various working groups during the past two decades using a wide range of model and palaeoproxy reconstruction approaches. While some studies indicated an abrupt collapse of vegetation at the end of the AHP, others suggested a gradual decline. Claussen et al. (2013 introduced a new aspect in the discussion, proposing that plant diversity in terms of moisture requirements could affect the strength of climate–vegetation feedback. In a conceptual model study, the authors illustrated that high plant diversity could stabilize an ecosystem, whereas a reduction in plant diversity might allow for an abrupt regime shift under gradually changing environmental conditions. Based on recently published pollen data and the current state of ecological literature, we evaluate the representation of climate–vegetation feedback in this conceptual approach, and put the suggested conclusions into an ecological context. In principle, the original model reproduces the main features of different plant types interacting together with climate although vegetation determinants other than precipitation are neglected. However, the model cannot capture the diversity of AHP vegetation. Especially tropical gallery forest taxa, indirectly linked to local precipitation, are not appropriately represented. In order to fill the gaps in the description of plant types regarding AHP diversity, we modify the original model in four main aspects. First, the growth ranges in terms of moisture requirements are extended by upper limits to represent full environmental envelopes. Second, data-based AHP plant types replace

  6. Emergence of indigenous vegetation classifications through integration of traditional ecological knowledge and remote sensing analyses.

    Naidoo, Robin; Hill, Kim

    2006-09-01

    Traditional ecological knowledge (TEK) can play an important role in the understanding of ecological systems. Although TEK has complemented scientific and managerial programs in a variety of contexts, its formal incorporation into remote sensing exercises has to date been limited. Here, we show that the vegetation classifications of the Ache, an indigenous hunter-gatherer tribe of the Mbaracayu Forest Reserve in Paraguay, are reflected in a supervised classification of satellite imagery of the reserve. Accuracy of classification was toward the low end of the range of published values, but was reasonable given the difficult nature of separating forest classes from satellite images. Comparison of the resultant map with a more traditionally elaborated vegetation map highlights differences between the two approaches and the gain in information obtained by considering TEK classifications. We suggest that integration of TEK and remote sensing may provide alternative insights into the ecology of vegetation communities and land cover, particularly in remote and densely forested areas where ecological field research is often limited by roads and/or trail systems.

  7. Ecological Land Type Associations of Minnesota

    Minnesota Department of Natural Resources — This coverage provides information for the fourth level of the Ecological Classification System. Polygon boundaries were delineated at a scale of 1:100,000 with a...

  8. Weed vegetation ecology of arable land in Salalah, Southern Oman.

    El-Sheikh, Mohamed A

    2013-07-01

    This paper applies multivariate statistical methods to a data set of weed relevés from arable fields in two different habitat types of coastal and mountainous escarpments in Southern Oman. The objectives were to test the effect of environmental gradients, crop plants and time on weed species composition, to rank the importance of these particular factors, and to describe the patterns of species composition and diversity associated with these factors. Through the application of TWINSPAN, DCA and CCA programs on data relating to 102 species recorded in 28 plots and farms distributed in the study area, six plant communities were identified: I- Dichanthium micranthum, II- Cynodon dactylon-D. micranthum, III- Convolvulus arvensis, IV- C. dactylon-Sonchus oleraceus, V- Amaranthus viridis and VI- Suaeda aegyptiaca-Achyranthes aspera. The ordination process (CCA) provided a sequence of plant communities and species diversity that correlated with some anthropogenic factors, physiographic variables and crop types. Therefore, length of time since farm construction, disturbance levels and altitude are the most important factors related to the occurrence of the species. The perennial species correlated with the more degraded mountain areas of new farm stands, whereas most of the annuals correlated with old lowland and less disturbed farms.

  9. Comparison of total polyphenol contents And antioxidant activity in cruciferous vegetables grown in diversified ecological conditions

    Joanna Kapusta-Duch

    2012-12-01

    Full Text Available Background.The aim of this study was to compare total polyphenol contents and antioxidant activity of three species of cruciferous vegetables grown under diversified ecological conditions for three consecutive years. Material and methods. Methanol extracts were prepared to be used to determine (spectrometrically the content of total phenolics, using the Folin-Ciocalteau reagent and antioxidant activity by identifying the sam- ple’s ability to extinguish an ABTS•+free radical. Results.All these species of cruciferous vegetables contained similar total polyphenols amounts regardless of its origin. Only red cabbage from organic farms was characterized by significantly higher antioxidant activity compared to vegetables purchased from local retailers in Cracow and similar or those cultivated near the steelworks. In white cabbage from farms located in a former steelworks protection zone a higher antioxidant activity was found than in organically grown vegetables and similar to that in vegetables available in retail. Brussels sprouts was characterised by a similar antioxidant activity regardless of its origin. Conclusions. On the basis of the present study, it cannot be concluded that organically grown cruciferous vegetables generally have higher contents of health-promoting secondary metabolites in comparison with the conventionally cultivated ones.

  10. Alternatives to sowing vegetable type soybeans

    Edcarlos Mannfredini

    1998-08-01

    Full Text Available Today, soybean crops of the Tamba Kurodaisu cultivar are sown in beds prior to transplantation to the field. This planting system has caused crop failure due to damage to the root system. An experiment to test different sowing alternatives to obtain plantlets for cropping of food type big seeded soybean was set up with the following treatments: sowing in beds; sowing in 130 cm³ newspaper cups; sowing in test tubes of volumes of 30 cm³, 60 cm³ and 70 cm³; sowing in 70 cm³ disposable plastic cups; sowing on 90 cm³ styrofoam trays. A randomized complete block design was used, and the following traits were assessed: germination percentage; number of days to flowering; plant height at flowering; number of days to maturity; plant height at maturity; number of seeds per plant; individual plant yield; weight of a hundred seeds. Results should that three methods could be used to set up Tamba Kurodaisu cultivar crops: sowing in disposable plastic cups, sowing in beds with later transplant, or direct sowing in the field.Atualmente, as lavouras com o cultivar Tamba Kurodaisu são semeadas em canteiros, para posterior transplante no campo. Este sistema tem causado falhas na lavoura, por ocorrer danificação no sistema radicular. Com o objetivo de testar diferentes alternativas de semeadura para obtenção de mudas visando a implantação de lavouras de soja tipo alimento, com sementes graúdas, instalou-se um experimento com os seguintes tratamentos: Semeadura em canteiros; Semeadura em copos de jornal, com volume (V igual a 130 cm³; Semeadura em tubetes, com V = 30 cm³; V = 60 cm³; V = 70 cm³; Semeadura em copos plásticos descartáveis, com V = 70 cm³; Semeadura em bandejas de isopor, com V = 90cm³. O delineamento utilizado foi blocos casualizados, tendo sido avaliados os seguintes caracteres: Porcentagem de germinação; Número de plantas por parcela; Número de dias para o florescimento; Altura da planta no florescimento; Número de dias

  11. Evaluation of Polarimetric SAR Decomposition for Classifying Wetland Vegetation Types

    Sang-Hoon Hong

    2015-07-01

    Full Text Available The Florida Everglades is the largest subtropical wetland system in the United States and, as with subtropical and tropical wetlands elsewhere, has been threatened by severe environmental stresses. It is very important to monitor such wetlands to inform management on the status of these fragile ecosystems. This study aims to examine the applicability of TerraSAR-X quadruple polarimetric (quad-pol synthetic aperture radar (PolSAR data for classifying wetland vegetation in the Everglades. We processed quad-pol data using the Hong & Wdowinski four-component decomposition, which accounts for double bounce scattering in the cross-polarization signal. The calculated decomposition images consist of four scattering mechanisms (single, co- and cross-pol double, and volume scattering. We applied an object-oriented image analysis approach to classify vegetation types with the decomposition results. We also used a high-resolution multispectral optical RapidEye image to compare statistics and classification results with Synthetic Aperture Radar (SAR observations. The calculated classification accuracy was higher than 85%, suggesting that the TerraSAR-X quad-pol SAR signal had a high potential for distinguishing different vegetation types. Scattering components from SAR acquisition were particularly advantageous for classifying mangroves along tidal channels. We conclude that the typical scattering behaviors from model-based decomposition are useful for discriminating among different wetland vegetation types.

  12. [Influence of three types of riparian vegetation on fluvial erosion control in Pantanos de Centla, Mexico].

    Sepúlveda-Lozada, Alejandra; Geissen, Violette; Ochoa-Gaona, Susana; Jarquín-Sánchez, Aarón; de la Cruz, Simón Hernández; Capetillo, Edward; Zamora-Cornelio, Luis Felipe

    2009-12-01

    Wetlands constitute very important ecological areas. The aim of this study was to quantify the soil losses due to fluvial erosion from 2006 to 2008 in two riverbanks under three types of vegetal coverage dominated by Haematoxylum campechianum, Dalbergia brownei and Brachiaria mutica, in the Pantanos de Centla Biosphere Reserve, SE Mexico. The relationship between the texture, organic matter and pH of soils and soil losses was evaluated. We used erosion sticks to estimate soil losses in 18 plots (three plots per type, three vegetation types, two riverbanks). Soil loss decreased in this order: H. campechianum>B. mutica>D. brownei indicating that D. brownei scrubland has the most potential to retain soil. The higher erosive impact within H. campechianum sites can be related with the low density of these trees in the study areas, as well as the lack of association with other types of vegetation that could reinforce the rooting of the soil profile. Furthermore, soil losses in H. campechianum sites were dependent on soil texture. The soils under this type of vegetal coverage were mainly sandy, which are more vulnerable to the erosive action in comparison with fine textured soils or soils with higher clay content, like the ones found in D. brownei and B. mutica sites. Soil losses of 100 % in the second year (B. mutica plots) can be attributed to the distribution of roots in the upper soil layer and also to livestock management along riverbanks. This study recognizes the importance of D. brownei scrublands in riverbank soil retention. Nevertheless it is necessary to consider the role of an entire vegetal community in future research.

  13. Performance Evaluation and Field Application of Red Clay Green Roof Vegetation Blocks for Ecological Restoration Projects

    Hwang-Hee Kim

    2017-02-01

    Full Text Available In this study, for restoration of ecological systems in buildings, porous vegetation red clay green roof blocks were designed for performance evaluation. Blast furnace slag (BFS; fine aggregates (agg., coarse aggregates, polyvinyl alcohol (PVA fiber (hydrophilic fiber, and red clay (ecofriendly additive material were applied to the construction of the porous vegetation red clay green roof blocks. A decrease in cement use is one way of reducing carbon emissions. To increase the water retentivity and the efficiency of roof vegetation blocks, blast furnace slag aggregates with excellent water absorptivity and polyvinyl alcohol fiber with a water absorption rate above 20% were added. In particular, the addition of polyvinyl alcohol fiber prevents performance reduction of the green roof vegetation blocks during freezing and melting in winter. Compressive strength, void ratio, and unit-mass tests were conducted to evaluate the performance of the roof vegetation blocks. After their application to roof vegetation, the effect of water purification was evaluated. According to the experimental results, the mix that satisfies the target performance of green roof vegetation blocks (compression strength above 8 MPa, void ratio above 20%, unit mass 2.0 kg/cm3 or below is: cement = 128.95 kg/m3, BFS = 96.75 kg/m3, red clay = 96.75 kg/m3, water = 81.50 kg/m3, BFS agg. = 1450 kg/m3, PVA fiber = 1.26 kg/m3. The green roof vegetation blocks were designed using the mix that satisfied the target performance. To find the amount of attainable water due to rainfall, a rainfall meter was installed after application of the roof vegetation to measure daily rainfall and calculate the amount of attainable water. The results show that, for 1 mm of rainfall, it is possible to attain about 0.53 L of water per 1 m2. In addition, the water quality of effluents after application of roof vegetation was analyzed, and the results satisfied Class 4 of the River-life Environmental

  14. Local food environment and fruit and vegetable consumption: An ecological study

    Mariana Carvalho Menezes

    2017-03-01

    Full Text Available Ecological studies are essential for understanding the environment-diet relationship. The purpose of this study was to describe environmental conditions and their relationship with fruit and vegetable (FV consumption among Brazilian public health service users in the city of Belo Horizonte. We evaluated food stores contained within 1600 m buffer zones at 18 Health Academy Programme sites, from 2013 to 2014. Variables at the community (density, proximity and type and the consumer (sectional location of FV; availability, quality, variety, price and advertising of FV and ultra-processed foods nutrition environment were measured by direct observation, while aggregate data from users (income and FV consumption were obtained by interview. Data were analysed using the Kernel intensity estimator, average nearest neighbour value and Local Moran's Index for local spatial autocorrelation. We interviewed 3414 users and analysed 336 food stores. Major geographical variations in the FV consumption were identified. Average consumption was higher (site 2A: 410.5 ± 185.7 g vs. site 4B: 311.2 ± 159.9 g in neighbourhoods with higher income and concentration of food stores, and better index of access to healthy foods. Sites with poor FV consumption had the most stores with poor access to healthy foods (index in the first tertile, ≤10. In conclusion, negative characteristics of the food environment, as seen in the present study, may contribute to low FV consumption, suggesting the need for the development and consolidation of public policies aimed at creating healthy environments through built environment interventions that increase access to and consumption of healthy foods like FV.

  15. Local food environment and fruit and vegetable consumption: An ecological study.

    Menezes, Mariana Carvalho; Costa, Bruna Vieirade Lima; Oliveira, Cláudia Di Lorenzo; Lopes, Aline Cristine Souza

    2017-03-01

    Ecological studies are essential for understanding the environment-diet relationship. The purpose of this study was to describe environmental conditions and their relationship with fruit and vegetable (FV) consumption among Brazilian public health service users in the city of Belo Horizonte. We evaluated food stores contained within 1600 m buffer zones at 18 Health Academy Programme sites, from 2013 to 2014. Variables at the community (density, proximity and type) and the consumer (sectional location of FV; availability, quality, variety, price and advertising of FV and ultra-processed foods) nutrition environment were measured by direct observation, while aggregate data from users (income and FV consumption) were obtained by interview. Data were analysed using the Kernel intensity estimator, average nearest neighbour value and Local Moran's Index for local spatial autocorrelation. We interviewed 3414 users and analysed 336 food stores. Major geographical variations in the FV consumption were identified. Average consumption was higher (site 2A: 410.5 ± 185.7 g vs. site 4B: 311.2 ± 159.9 g) in neighbourhoods with higher income and concentration of food stores, and better index of access to healthy foods. Sites with poor FV consumption had the most stores with poor access to healthy foods (index in the first tertile, ≤ 10). In conclusion, negative characteristics of the food environment, as seen in the present study, may contribute to low FV consumption, suggesting the need for the development and consolidation of public policies aimed at creating healthy environments through built environment interventions that increase access to and consumption of healthy foods like FV.

  16. Wood-inhabiting fungi in southern Italy forest stands: morphogroups, vegetation types and decay classes.

    Granito, Vito Mario; Lunghini, Dario; Maggi, Oriana; Persiani, Anna Maria

    2015-01-01

    The authors conducted an ecological study of forests subjected to varying management. The aim of the study was to extend and integrate, within a multivariate context, knowledge of how saproxylic fungal communities behave along altitudinal/vegetational gradients in response to the varying features and quality of coarse woody debris (CWD). The intra-annual seasonal monitoring of saproxylic fungi, based on sporocarp inventories, was used to investigate saproxylic fungi in relation to vegetation types and management categories. We analyzed fungal species occurrence, recorded according to the presence/absence and frequency of sporocarps, on the basis of the harvest season, of coarse woody debris decay classes as well as other environmental and ecological variables. Two-way cluster analysis, DCA and Spearman's rank correlations, for indirect gradient analysis, were performed to identify any patterns of seasonality and decay. Most of the species were found on CWD in an intermediate decay stage. The first DCA axis revealed the vegetational/microclimate gradient as the main driver of fungal community composition, while the second axis corresponded to a strong gradient of CWD decay classes.

  17. Forests, savannas and grasslands: bridging the knowledge gap between ecology and Dynamic Global Vegetation Models

    M. Baudena

    2014-06-01

    Full Text Available The forest, savanna, and grassland biomes, and the transitions between them, are expected to undergo major changes in the future, due to global climate change. Dynamic Global Vegetation Models (DGVMs are very useful to understand vegetation dynamics under present climate, and to predict its changes under future conditions. However, several DGVMs display high uncertainty in predicting vegetation in tropical areas. Here we perform a comparative analysis of three different DGVMs (JSBACH, LPJ-GUESS-SPITFIRE and aDGVM with regard to their representation of the ecological mechanisms and feedbacks that determine the forest, savanna and grassland biomes, in an attempt to bridge the knowledge gap between ecology and global modelling. Model outcomes, obtained including different mechanisms, are compared to observed tree cover along a mean annual precipitation gradient in Africa. Through these comparisons, and by drawing on the large number of recent studies that have delivered new insights into the ecology of tropical ecosystems in general, and of savannas in particular, we identify two main mechanisms that need an improved representation in the DGVMs. The first mechanism includes water limitation to tree growth, and tree-grass competition for water, which are key factors in determining savanna presence in arid and semi-arid areas. The second is a grass-fire feedback, which maintains both forest and savanna occurrences in mesic areas. Grasses constitute the majority of the fuel load, and at the same time benefit from the openness of the landscape after fires, since they recover faster than trees. Additionally, these two mechanisms are better represented when the models also include tree life stages (adults and seedlings, and distinguish between fire-prone and shade-tolerant savanna trees, and fire-resistant and shade-intolerant forest trees. Including these basic elements could improve the predictive ability of the DGVMs, not only under current climate

  18. Using ecological forecasting of future vegetation transition and fire frequency change in the Sierra Nevada to assess fire management strategies

    Thorne, J. H.; Schwartz, M. W.; Holguin, A. J.; Moritz, M.; Batllori, E.; Folger, K.; Nydick, K.

    2013-12-01

    Ecological systems may respond in complex manners as climate change progresses. Among the responses, site-level climate conditions may cause a shift in vegetation due to the physiological tolerances of plant species, and the fire return interval may change. Natural resource managers challenged with maintaining ecosystem health need a way to forecast how these processes may affect every location, in order to determine appropriate management actions and prioritize locations for interventions. We integrated climate change-driven vegetation type transitions with projected change in fire frequency for 45,203 km2 of the southern Sierra Nevada, California, containing over 10 land management agencies as well as private lands. This Magnitude of Change (MOC) approach involves classing vegetation types in current time according to their climate envelopes, and identifying which sites will in the future have climates beyond what that vegetation currently occurs in. Independently, fire models are used to determine the change in fire frequency for each site. We examined 82 vegetation types with >50 grid cell occurrences. We found iconic resources such as the giant sequoia, lower slope oak woodlands, and high elevation conifer forests are projected as highly vulnerable by models that project a warmer drier future, but not as much by models that project a warmer future that is not drier than current conditions. Further, there were strongly divergent vulnerabilities of these forest types across land ownership (National Parks versus US Forest Service lands), and by GCM. For example, of 50 giant sequoia (Sequoiadendron giganteum) groves and complexes, all but 3 (on Sierra National Forest) were in the 2 highest levels of risk of climate and fire under the GFDL A2 projection, while 15 groves with low-to-moderate risk were found on both the National Parks and National Forests 18 in the 2 under PCM A2. Landscape projections of potential MOC suggest that the region is likely to experience

  19. Characteristic of Soil Hydro-Physical Properties and Water Dynamics under Different Vegetation Restoration Types

    MA Zelong; GONG Yuanbo; HU Tingxing

    2006-01-01

    By combining the observation of the soil profile at field and the chemical and physical analysis in laboratory, a study on the hydro-physical properties of soil in six different vegetation types and the dynamics of water content after rain was conducted in Wanchanggou, Guangyuan City to find out the vegetation types with effective water-conservation functions in order to serve the ecological restoration in the low hill heavy rain area upper the Jialing River. Results showed that:the hydro-physical properties of soil in the mixed Alnus cremastogyne and Cupressua Leyland forest (AcCl) were best. But in the depth of 0-20 cm. The properties of soil in the abandoned cropland (Fm) was better than that in the AcCl. The soil bulk densities varied significantly between the layers of 0-20 cm and 20-40 cm in all the six vegetation types except that in the Robinia pseudoacacia shrub forest (RpⅡ), and the changes of the maximum and the capillary moisture capacity between layers were significant only in the Fm and in the AcCl. Of these stands, the AcCl had the shortest water-absorbing period and the strongest moisture changes in the upper layer (0-15 cm). In the same stand, the deeper the soil layer, the slighter the soil moisture varied, and the longer the soil moisture accumulating process lasted.

  20. Qualitative parameters of non-traditional types of vegetables

    Eva Kudrnáčová

    2015-08-01

    Full Text Available The main aim of this study was to determine selected quality indicators of non-traditional types of leafy vegetables. Mizuna (Brassica rapa japonica, Chinese mustard (Brassica juncea, edible chrysanthemum (Chrysanthemum coronarium and arugula (Eruca sativa belonged among the selected species of vegetables. During the one-year experiment, spring and autumn sowing was carried out for these species of vegetables. The measured quality parameters were the content of nitrates and ascorbic acid. Sampling was done in the morning and in the laboratory, the samples were further processed according to the type of determination. To determine the content of nitrates and ascorbic acid, leaves were removed from plants. The filtrate from the leaves was then prepared. Determination of nitrates and ascorbic acid was carried out using a special test strip and device Rqflex plus 10. The results of measurement of both sowing varieties were compared. Total nitrate content was higher up to 22% in plants sown in the autumn except edible chrysanthemum (Chrysanthemum coronarium. The highest content was recorded in arugula (Eruca sativa, which was recently implemented to the studies of the European Union and for which there were set the limits of nitrates. Overall, the nitrate content ranged from 221 to 334 ppm in spring varieties and from 249 to 384 mg/kg in autumn varieties. Ascorbic acid content was very high in Chinese mustard (Brassica juncea, edible chrysanthemum (Chrysanthemum coronarium and arugula (Eruca sativa in both spring and autumn varieties. Values of ascorbic acid ranged from 839 in autumn sowing up to 2909 mg/kg in spring sowing. These non-traditional types of leafy vegetables could be included among the other importants sources of vitamin C in the future.  

  1. Ecological zones of California deserts

    U.S. Geological Survey, Department of the Interior — The dataset delineates ecological zones within California deserts. We derived ecological zones by reclassifying LANDFIRE vegetation biophysical setting types, plus...

  2. Technology versus Agro-Ecology in Designing Vegetable Production Systems in the Netherlands

    Haan, de J.J.; Sukkel, W.; Stilma, E.S.C.

    2010-01-01

    Current open field vegetable production systems in the Netherlands do not meet market and societal demands. These demands could not be fulfilled by adapting current production systems. Other kinds of production systems are needed and therefore two types of systems are designed by 1) a technological

  3. An integrated probabilistic assessment to analyse stochasticity of soil erosion in different restoration vegetation types

    Zhou, Ji; Fu, Bojie; Gao, Guangyao; Lü, Yihe; Wang, Shuai

    2017-03-01

    The stochasticity of soil erosion reflects the variability of soil hydrological response to precipitation in a complex environment. Assessing this stochasticity is important for the conservation of soil and water resources; however, the stochasticity of erosion event in restoration vegetation types in water-limited environment has been little investigated. In this study, we constructed an event-driven framework to quantify the stochasticity of runoff and sediment generation in three typical restoration vegetation types (Armeniaca sibirica (T1), Spiraea pubescens (T2) and Artemisia copria (T3)) in closed runoff plots over five rainy seasons in the Loess Plateau of China. The results indicate that, under the same rainfall condition, the average probabilities of runoff and sediment in T1 (3.8 and 1.6 %) and T3 (5.6 and 4.4 %) were lowest and highest, respectively. The binomial and Poisson probabilistic model are two effective ways to simulate the frequency distributions of times of erosion events occurring in all restoration vegetation types. The Bayes model indicated that relatively longer-duration and stronger-intensity rainfall events respectively become the main probabilistic contributors to the stochasticity of an erosion event occurring in T1 and T3. Logistic regression modelling highlighted that the higher-grade rainfall intensity and canopy structure were the two most important factors to respectively improve and restrain the probability of stochastic erosion generation in all restoration vegetation types. The Bayes, binomial, Poisson and logistic regression models constituted an integrated probabilistic assessment to systematically simulate and evaluate soil erosion stochasticity. This should prove to be an innovative and important complement in understanding soil erosion from the stochasticity viewpoint, and also provide an alternative to assess the efficacy of ecological restoration in conserving soil and water resources in a semi-arid environment.

  4. Drought offset ecological restoration program-induced increase in vegetation activity in the Beijing-Tianjin Sand Source Region, China.

    Wu, Zhitao; Wu, Jianjun; He, Bin; Liu, Jinghui; Wang, Qianfeng; Zhang, Hong; Liu, Yong

    2014-10-21

    To improve the ecological conditions, the Chinese government adopted six large-scale ecological restoration programs including 'Three-North Shelterbelt Project', "Grain for Green Project" and "Beijing-Tianjin Sand Source Control Project". Meanwhile, these ecologically vulnerable areas have experienced frequent droughts. However, little attention has been paid to the impact of drought on the effectiveness of these programs. Taking Beijing-Tianjin Sand Source Region (BTSSR) as study area, we investigated the role of droughts and ecological restoration program on trends of vegetation activities and to address the question of a possible "drought signal" in assessing effectiveness of ecological restoration program. The results demonstrate the following: (1) Vegetation activity increased in the BTSSR during 2000-2010, with 58.44% of the study area showing an increased NDVI, of which 11.80% had a significant increase at 0.95 confidential level. The decreasing NDVI trends were mainly concentrated in a southwest-to-northeast strip in the study area. (2) Drought was the main driving force for a decreasing trend of vegetation activity in the southwest-to-northeast regions of the BTSSR at the regional and spatial scales. Summer droughts in 2007 and 2009 contributed to the decreasing trend in NDVI. The severe and extreme droughts in summer reduced the NDVI by approximately 13.06% and 23.55%, respectively. (3) The residual analysis result showed that human activities, particularly the ecological restoration programs, have a positive impact on vegetation change. Hence, the decreasing trends in the southwest-to-northeast regions of the BTSSR cannot be explained by the improper ecological restoration program and is partly explained by droughts, especially summer droughts. Therefore, drought offset the ecological restoration program-induced increase in vegetation activity in the BTSSR.

  5. Multivariate Analysis, Description, and Ecological Interpretation of Weed Vegetation in the Summer Crop Fields of Anhui Province, China

    Sheng QIANG

    2005-01-01

    Two surveys were conducted to investigate weed vegetation in a 153-hm2 sampling area of summer crop fields from Anhui Province, China, through visual scoring of the level of weed infestation compared with summer crops on a seven-class scale. In total, 155 sampling sites were selected in the field based on crops, tillage, rotation systems, geographical regions, and soil types across the province. Data on weed communities and environmental factors were collected and analyzed through principal component analysis (PCA) and canonical correspondence analysis (CCA), and the output was interpreted ecologically. Results showed that the main factors influencing the structure and distribution of weed communities in summer crop fields were the soil submersion period, latitude, and soil type and pH. The CCA indicated a significant relationship between weed dominance and soil submersion duration, latitude, and soil pH. From the result of the PCA and CCA ordination, the 155 sampling sites could be divided into three groups based on geographic and floristic composition, as well as weed abundance. The southern dry land group, which was characterized by a double-cropping system in the hilly regions of southern and central Anhui Province with a continuous summer crop and an autumn dry land crop, was dominated by Galium aparine Linn. var. tenerum (Gren. et Godr) Robb., Avenafatua L., and Veronica persica Poir. The northern dry land group, which had the same cropping system as the southern dry land group, was dominated by G. aparine var. tenerun, Galium tricorne Stokes, Descurainia sophia (L.) Schur., and Lithospermum arvense L. in the North Anhui Province, China. These two dry land groups could be combined into one large dry land group, in which the Galium weed vegetation type dominated. The third group was the paddy soil group, which was characterized by a continu ous summer crop and double- or triple-cropping systems of rice, and prevailed in the south and central areas of Anhui

  6. Seasonal contributions of vegetation types to suburban evapotranspiration

    Peters, Emily B.; Hiller, Rebecca V.; McFadden, Joseph P.

    2011-03-01

    Evapotranspiration is an important term of energy and water budgets in urban areas and is responsible for multiple ecosystem services provided by urban vegetation. The spatial heterogeneity of urban surface types with different seasonal water use patterns (e.g., trees and turfgrass lawns) complicates efforts to predict and manage urban evapotranspiration rates, necessitating a surface type, or component-based, approach. In a suburban neighborhood of Minneapolis-Saint Paul, Minnesota, United States, we simultaneously measured ecosystem evapotranspiration and its main component fluxes using eddy covariance and heat dissipation sap flux techniques to assess the relative contribution of plant functional types (evergreen needleleaf tree, deciduous broadleaf tree, cool season turfgrass) to seasonal and spatial variations in evapotranspiration. Component-based evapotranspiration estimates agreed well with measured water vapor fluxes, although the imbalance between methods varied seasonally from a 20% overestimate in spring to an 11% underestimate in summer. Turfgrasses represented the largest contribution to annual evapotranspiration in recreational and residential land use types (87% and 64%, respectively), followed by trees (10% and 31%, respectively), with the relative contribution of plant functional types dependent on their fractional cover and daily water use. Recreational areas had higher annual evapotranspiration than residential areas (467 versus 324 mm yr-1, respectively) and altered seasonal patterns of evapotranspiration due to greater turfgrass cover (74% versus 34%, respectively). Our results suggest that plant functional types capture much of the variability required to predict the seasonal patterns of evapotranspiration among cities, as well as differences in evapotranspiration that could result from changes in climate, land use, or vegetation composition.

  7. Physical activity, fruit and vegetable intake and the built environment: ecological and epidemiological studies among youth

    Svastisalee, Chalida

    .27-0.82) and girls (OR = 0.16; 0.05-0.52) from low social class background attending schools with low path exposure. In conclusion, at an ecological level, it is not evident that the spatial patterning of dietary and exercise resources can be attributed to socioeconomic or demographic characteristics. Studies based...... in the neighborhood, and could manifest itself in poor health behaviors. This concept is first studied at the neighborhood level, by examining the socioeconomic patterning of food and exercise resources. Next, at the individual level, I examine the combined effects of socioeconomic status and the built environment...... and health behaviors of 11-to-15-year old school children. Outcome measures for these studies were infrequent less than daily intake of fruit and vegetables (Paper II) and frequent vigorous physical activity of one hour or more per day (Paper IV). The individual dataset was appended with a validated...

  8. WETLAND TYPES AND ASSOCIATE VEGETATION IN NEPAL:AN OVERVIEW

    Mohan Siwakoti

    2007-01-01

    Wetland is the transitional zone between the permanently wet and dry environment and shares the characteristics of the environment. Wetland is not yet to be classified unambiguously as either aquatic or terrestrial. However, the Ramsar Convention adopts an extremely broad approach in determining the wetland; as a result, several varieties of habitat types are included under the wetland definition. Wetlands are among the world's most productive ecosystems and provide a wide variety of goods and services. Nepal lies on the southern slopes of central Himalayas and occupies a total area of 147 181 km2 between the latitudes 26°22′ N and 30°27′ N and the longitudes 80°40′ E and 88°12′ E. The diverse landscape (60-8 848 m) and bioclimatic conditions (alpine to tropical) of the country provide a unique niche for different types of wetlands. These are distributed from high altitudinal glacial lakes to hot springs, ponds, ox-bow lakes to river floodplains, marshes and swamps. The country has 15 types of inland freshwater natural wetlands as classified by the Ramsar Convention. These wetlands house several species of rare and endangered flora and fauna. The present paper attempts to highlight the various types of wetlands in Nepal with associate vegetation.

  9. Vegetation survey: a new focus for Applied Vegetation Science

    Chytry, M.; Schaminee, J.H.J.; Schwabe, A.

    2011-01-01

    Vegetation survey is an important research agenda in vegetation science. It defines vegetation types and helps understand differences among them, which is essential for both basic ecological research and applications in biodiversity conservation and environmental monitoring. In this editorial, we re

  10. Ecology of type II secretion in marine gammaproteobacteria.

    Evans, Flavia F; Egan, Suhelen; Kjelleberg, Staffan

    2008-05-01

    Compelling findings on the direct association of the type II secretion (T2S) system with different ecological functions in marine bacteria have challenged the traditional view of the T2S pathway, the function of which has been mostly studied in pathogenic bacteria. The availability of a number of whole-genome sequence data sets enabled the analysis of the genetic composition of the T2S system across a number of Vibrios and Alteromonads. The widespread Gammaproteobacteria, in particular the Alteromonadales and the Vibrionales group, are recognized to play significant roles in the cycling of nutrients in coastal and pelagic marine ecosystems and are also found associated with marine eukaryotes. The combined analysis of the role and the genetic composition of the T2S system in Gammaproteobacteria provides important evidence for the significance of the T2S pathway in the ecology of environmental bacteria.

  11. Vegetation Dynamics Depending on Ecological Particularities of Bozanta Mare (Maramures County-Romania Tailing Pound. Case Study

    Monica Marian

    2009-01-01

    Full Text Available The present study follows an ecological demarch of reintegration in the scenary through revegetation of an anthropic ground, consisting in a waste pond formed from the flotation activity of non-ferrous ores. Problem statement: To support the formation of a compact vegetal layer, having an anti-errosion and a restoration role, a preliminary study was required regarding the spontaneous settlement of different vegetal species. We have followed the specific floristic composition and the biodiversity on the waste pond, the manner of association of plant species, and the possible interractions with other species from the biocenosis (microorganisms and fungi. We have also studied the pace at which vegetal species settle, as well as the reciprocal influence, from the point of view of vegetation, with the neighbouring area, since the desideratum is the settlement of a vegetation similar to the natural one. Approach: The aim of the research is to draw a list of the vegetal taxa installed on the pond, as well as to detect some succession stages or some possible vegetal associations. We have established the share of different species in the vegetal layer on the waste pond through an analysis of the ecological preferences, of the geographical origin of plant species, of the cariological and bioform profile. All this was done to compare the possible vegetal associations which settle on such anthropic grounds with the neighbouring vegetation. The approach used was the classical one in fitosociology, recommended by the Central European Fitosociological School adapted to the pedo-climatic conditions in Romania. Results: Over 50 species of plants and fungi spontaniously settled have been listed, and we have followed their association as well as their distribution, compared to the microclimatical conditions of the waste pond. In this way,we have distinguished species with a large potential of revegetating highly polluted with heavy metals waste ponds and sites

  12. Potential effects of large linear pipeline construction on soil and vegetation in ecologically fragile regions.

    Xiao, Jun; Wang, Ya-Feng; Shi, Peng; Yang, Lei; Chen, Li-Ding

    2014-11-01

    Long-distance pipeline construction results in marked human disturbance of the regional ecosystem and brings into question the safety of pipeline construction with respect to the environment. Thus, the direct environmental impact and proper handling of such large projects have received much attention. The potential environmental effects, however, have not been fully addressed, particularly for large linear pipeline projects, and the threshold of such effects is unclear. In this study, two typical eco-fragile areas in western China, where large linear construction projects have been conducted, were chosen as the case study areas. Soil quality indices (SQI) and vegetation indices (VI), representing the most important potential effects, were used to analyze the scope of the effect of large pipeline construction on the surrounding environment. These two indices in different buffer zones along the pipeline were compared against the background values. The analysis resulted in three main findings. First, pipeline construction continues to influence the nearby eco-environment even after a 4-year recovery period. During this period, the effect on vegetation due to pipeline construction reaches 300 m beyond the working area, and is much larger in distance than the effect on soil, which is mainly confined to within 30 m either side of the pipeline, indicating that vegetation is more sensitive than soil to this type of human disturbance. However, the effect may not reach beyond 500 m from the pipeline. Second, the scope of the effect in terms of distance on vegetation may also be determined by the frequency of disturbance and the intensity of the pipeline construction. The greater the number of pipelines in an area, the higher the construction intensity and the more frequent the disturbance. Frequent disturbance may expand the effect on vegetation on both sides of the pipeline, but not on soil quality. Third, the construction may eliminate the stable, resident plant

  13. [Relationships between soil microbial ecological characteristics and physical-chemical properties of vegetable garden soil].

    Li, Ning; Li, Huaxing; Zhu, Fengjiao; Liu, Yuanjin; Kuang, Peirui

    2006-02-01

    The study on the 64 vegetable garden soil samples in the Baiyuan District of Guangzhou City showed that there were significantly positive correlations of soil microbial biomass carbon (Cmic) with soil total N, alkali-hydrolygable N, available K, cation exchange capacity (CEC) and organic matter (OM), of soil microbial biomass nitrogen (Nmic) with soil total N, total P, CEC and OM, of soil basal respiration (SBR) with soil total N, alkali-hydrolygable N, available K, CEC and OM, of AWCD with soil total N and OM, and of Shannon diversity index with soil total N and CEC. Low alkali-hydrolygable N increased Cmic SBR, and metabolic quotient (qCO2), while high alkali-hydrolygable N decreased qCO2. High available P decreased Cmic, Nmic and microbial quotient, and a high ratio of available P to alkali-hydrolygable N was related to the decrease of Cmic, Nmic, Cmic/Nmic and SBR. It was suggested that there were significant correlations between soil microbial ecological characteristics and physico-chemical properties, and excessive available nutrients or inappropriate ratios of alkali-hydrolygable N to available P in soil were harmful to soil microbes.

  14. Iron Ore Industry Emissions as a Potential Ecological Risk Factor for Tropical Coastal Vegetation

    Kuki, Kacilda N.; Oliva, Marco A.; Pereira, Eduardo G.

    2008-07-01

    In the coastal zone of the Espírito Santo state, Brazil, fragments of restinga, which form a natural ecosystem, share their space with an increasing number of iron ore industries. The iron ore dust and SO2 originating from the industry processing activities can interfere with the vegetation of the adjacent ecosystems at various levels. This study was undertaken in order to evaluate the effects of industry emissions on representative members of the restinga flora, by measuring physiological and phenological parameters. Foliar samples of Ipomoea pes caprae, Canavalia rosea, Sophora tomentosa, and Schinus terebinthifolius were collected at three increasing distances from an ore industry (1.0, 5.0, and 15.0 km), and were assessed for their dust deposition, chlorophyll, and Fe content. Phenological monitoring was focused on the formation of shoots, flowers, and fruits and was also performed throughout the course of a year. The results showed that the edaphic characteristics and the mineral constitutions of the plants were affected by industry emissions. In addition, the chlorophyll content of the four species increased with proximity to the industry. Phenological data revealed that the reproductive effort, as measured by fruit production, was affected by emissions and S. tomentosa was the most affected species. The use of an integrative approach that combines biochemical and ecological data indicates that the restinga flora is under stress due to industry emissions, which on a long-term basis may put the ecosystem at risk.

  15. Vegetation

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

    2012-01-01

    • Over the past 30 years (1982-2011), the Normalized Difference Vegetation Index (NDVI), an index of green vegetation, has increased 15.5% in the North American Arctic and 8.2% in the Eurasian Arctic. In the more southern regions of Arctic tundra, the estimated aboveground plant biomass has...

  16. Categorizing Grassland Vegetation with Full-Waveform Airborne Laser Scanning: A Feasibility Study for Detecting Natura 2000 Habitat Types

    András Zlinszky

    2014-08-01

    Full Text Available There is increasing demand for reliable, high-resolution vegetation maps covering large areas. Airborne laser scanning data is available for large areas with high resolution and supports automatic processing, therefore, it is well suited for habitat mapping. Lowland hay meadows are widespread habitat types in European grasslands, and also have one of the highest species richness. The objective of this study was to test the applicability of airborne laser scanning for vegetation mapping of different grasslands, including the Natura 2000 habitat type lowland hay meadows. Full waveform leaf-on and leaf-off point clouds were collected from a Natura 2000 site in Sopron, Hungary, covering several grasslands. The LIDAR data were processed to a set of rasters representing point attributes including reflectance, echo width, vegetation height, canopy openness, and surface roughness measures, and these were fused to a multi-band pseudo-image. Random forest machine learning was used for classifying this dataset. Habitat type, dominant plant species and other features of interest were noted in a set of 140 field plots. Two sets of categories were used: five classes focusing on meadow identification and the location of lowland hay meadows, and 10 classes, including eight different grassland vegetation categories. For five classes, an overall accuracy of 75% was reached, for 10 classes, this was 68%. The method delivers unprecedented fine resolution vegetation maps for management and ecological research. We conclude that high-resolution full-waveform LIDAR data can be used to detect grassland vegetation classes relevant for Natura 2000.

  17. Community Structure of Skipper Butterflies (Lepidoptera, Hesperiidae) along Elevational Gradients in Brazilian Atlantic Forest Reflects Vegetation Type Rather than Altitude

    Carneiro, Eduardo; Mielke, Olaf Hermann Hendrik; Casagrande, Mirna Martins; Fiedler, Konrad

    2014-01-01

    Species turnover across elevational gradients has matured into an important paradigm of community ecology. Here, we tested whether ecological and phylogenetic structure of skipper butterfly assemblages is more strongly structured according to altitude or vegetation type along three elevation gradients of moderate extent in Serra do Mar, Southern Brazil. Skippers were surveyed along three different mountain transects, and data on altitude and vegetation type of every collection site were recorded. NMDS ordination plots were used to assess community turnover and the influence of phylogenetic distance between species on apparent community patterns. Ordinations based on ecological similarity (Bray-Curtis index) were compared to those based on phylogenetic distance measures (MPD and MNTD) derived from a supertree. In the absence of a well-resolved phylogeny, various branch length transformation methods were applied together with four different null models, aiming to assess if results were confounded by low-resolution trees. Species composition as well as phylogenetic community structure of skipper butterflies were more prominently related to vegetation type instead of altitude per se. Phylogenetic distances reflected spatial community patterns less clearly than species composition, but revealed a more distinct fauna of monocot feeders associated with grassland habitats, implying that historical factors have played a fundamental role in shaping species composition across elevation gradients. Phylogenetic structure of community turned out to be a relevant additional tool which was even superior to identify faunal contrasts between forest and grassland habitats related to deep evolutionary splits. Since endemic skippers tend to occur in grassland habitats in the Serra do Mar, inclusion of phylogenetic diversity may also be important for conservation decisions. PMID:25272004

  18. Applying the socio-ecological model to improving fruit and vegetable intake among low-income African Americans.

    Robinson, Tanya

    2008-12-01

    Despite the growing body of literature that provides evidence of the health benefits of a diet high in fruits and vegetables, most Americans eat much less than the recommended amounts of this food group. Among those who are least likely to meet the USDA guidelines for the recommended daily servings of fruits and vegetables are non-Hispanic Blacks and individuals with lower incomes. The purpose of this literature review is to examine the dietary behaviors, focusing on fruit and vegetable intake, of low-income African Americans from a socio-ecological perspective, and to offer rationale for and guidance on integrating socio-ecological concepts into health promoting programs intended to improve dietary behaviors among this population. Based on the 12 descriptive studies retrieved in the review, dietary behaviors and fruit and vegetable intake among African Americans are the result of a complex interplay of personal, cultural, and environmental factors that can be categorized and described using the five levels of influence conceptualized by the socio-ecological model: Intrapersonal level (taste preferences, habits, and nutritional knowledge and skills), Interpersonal level/social environment (processes whereby culture, social traditions, and role expectations impact eating practices; and patterns within peer groups, friends and family), and Organizational, Community, and Public Policy levels/physical environment (environmental factors that affect food access and availability). The socio-ecological model provides a useful framework for achieving a better understanding of the multiple factors and barriers that impact dietary behaviors, and therefore can provide guidance for developing culturally appropriate and sensitive intervention strategies for African Americans. It is an integrative framework that shows great promise in moving the field closer to attaining the goal of improving dietary behaviors and nutritional status among African Americans.

  19. Ecología vegetal en la Antártida

    L.G. Sancho

    2011-01-01

    Full Text Available A menudo se ha descrito la vida vegetal en la Antártida como extremadamente pobre y ecológicamente simple. Sin embargo, esto sólo es cierto si nos referimos a las localidades más inhóspitas de la Antártida continental. En la región conocida como Antártida marítima, costa occidental de la Península Antártica e islas adyacentes, la situación es bien distinta. El número de especies de líquenes supera las 350 y se han descrito más de 100 especies de musgos y hepáticas, aunque sólo existen dos plantas con flores. En el ámbito de la ecología vegetal, la cuestión fundamental que ha preocupado a los investigadores hasta ahora es si los líquenes y musgos de la Antártida presentan algún tipo de adaptación que les permita sobrevivir mejor que otras plantas en este medio. Un segundo aspecto de gran interés en la actualidad es determinar la capacidad de adaptación de la flora antártica ante el aumento de la radiación ultravioleta (UV como consecuencia del agujero de ozono, y ante el calentamiento global. Los líquenes antárticos se han mostrado muy tolerantes a amplios periodos de frío y sequía y son capaces de mantener una fotosíntesis activa a temperatura por debajo del punto de congelación, sin embargo algunas de las especies estudiadas no son capaces de mantener tasas positivas de fotosíntesis si la temperatura sube dos o tres grados. Por otra parte, tanto musgos como líquenes se muestran muy resistentes a la radiación UV. Los líquenes y comunidades microbianas de los Valles Secos y Montañas Transantárticas no parecen limitados por la más dura combinación de frío, sequedad y radiación que se produce en nuestro planeta. Estas especies son excelentes candidatos para experimentos de astrobiología en el espacio exterior, con el fin de demostrar la capacidad de supervivencia de células complejas originadas en la Tierra a posibles transferencias interplanetarias.

  20. Review of vegetable fermentations with particular emphasis on processing modifications, microbial ecology, and spoilage

    The consumption of vegetables is widespread in the world and represents a major component of the human diet. Microorganisms (mainly lactic acid bacteria, yeasts, Enterobacteriaceae, Propionibacterium and Clostridium species) play a significant role in vegetable fermentations, affecting the quality a...

  1. Vertical and Horizontal Vegetation Structure across Natural and Modified Habitat Types at Mount Kilimanjaro.

    Rutten, Gemma; Ensslin, Andreas; Hemp, Andreas; Fischer, Markus

    2015-01-01

    In most habitats, vegetation provides the main structure of the environment. This complexity can facilitate biodiversity and ecosystem services. Therefore, measures of vegetation structure can serve as indicators in ecosystem management. However, many structural measures are laborious and require expert knowledge. Here, we used consistent and convenient measures to assess vegetation structure over an exceptionally broad elevation gradient of 866-4550 m above sea level at Mount Kilimanjaro, Tanzania. Additionally, we compared (human)-modified habitats, including maize fields, traditionally managed home gardens, grasslands, commercial coffee farms and logged and burned forests with natural habitats along this elevation gradient. We distinguished vertical and horizontal vegetation structure to account for habitat complexity and heterogeneity. Vertical vegetation structure (assessed as number, width and density of vegetation layers, maximum canopy height, leaf area index and vegetation cover) displayed a unimodal elevation pattern, peaking at intermediate elevations in montane forests, whereas horizontal structure (assessed as coefficient of variation of number, width and density of vegetation layers, maximum canopy height, leaf area index and vegetation cover) was lowest at intermediate altitudes. Overall, vertical structure was consistently lower in modified than in natural habitat types, whereas horizontal structure was inconsistently different in modified than in natural habitat types, depending on the specific structural measure and habitat type. Our study shows how vertical and horizontal vegetation structure can be assessed efficiently in various habitat types in tropical mountain regions, and we suggest to apply this as a tool for informing future biodiversity and ecosystem service studies.

  2. Vertical and Horizontal Vegetation Structure across Natural and Modified Habitat Types at Mount Kilimanjaro.

    Gemma Rutten

    Full Text Available In most habitats, vegetation provides the main structure of the environment. This complexity can facilitate biodiversity and ecosystem services. Therefore, measures of vegetation structure can serve as indicators in ecosystem management. However, many structural measures are laborious and require expert knowledge. Here, we used consistent and convenient measures to assess vegetation structure over an exceptionally broad elevation gradient of 866-4550 m above sea level at Mount Kilimanjaro, Tanzania. Additionally, we compared (human-modified habitats, including maize fields, traditionally managed home gardens, grasslands, commercial coffee farms and logged and burned forests with natural habitats along this elevation gradient. We distinguished vertical and horizontal vegetation structure to account for habitat complexity and heterogeneity. Vertical vegetation structure (assessed as number, width and density of vegetation layers, maximum canopy height, leaf area index and vegetation cover displayed a unimodal elevation pattern, peaking at intermediate elevations in montane forests, whereas horizontal structure (assessed as coefficient of variation of number, width and density of vegetation layers, maximum canopy height, leaf area index and vegetation cover was lowest at intermediate altitudes. Overall, vertical structure was consistently lower in modified than in natural habitat types, whereas horizontal structure was inconsistently different in modified than in natural habitat types, depending on the specific structural measure and habitat type. Our study shows how vertical and horizontal vegetation structure can be assessed efficiently in various habitat types in tropical mountain regions, and we suggest to apply this as a tool for informing future biodiversity and ecosystem service studies.

  3. Temporal dynamics of spectral bioindicators evidence biological and ecological differences among functional types in a cork oak open woodland

    Cerasoli, Sofia; Costa e Silva, Filipe; Silva, João M. N.

    2016-06-01

    The application of spectral vegetation indices for the purpose of vegetation monitoring and modeling increased largely in recent years. Nonetheless, the interpretation of biophysical properties of vegetation through their spectral signature is still a challenging task. This is particularly true in Mediterranean oak forest characterized by a high spatial and temporal heterogeneity. In this study, the temporal dynamics of vegetation indices expected to be related with green biomass and photosynthetic efficiency were compared for the canopy of trees, the herbaceous layer, and two shrub species: cistus ( Cistus salviifolius) and ulex ( Ulex airensis). coexisting in a cork oak woodland. All indices were calculated from in situ measurements with a FieldSpec3 spectroradiometer (ASD Inc., Boulder, USA). Large differences emerged in the temporal trends and in the correlation between climate and vegetation indices. The relationship between spectral indices and temperature, radiation, and vapor pressure deficit for cork oak was opposite to that observed for the herbaceous layer and cistus. No correlation was observed between rainfall and vegetation indices in cork oak and ulex, but in the herbaceous layer and in the cistus, significant correlations were found. The analysis of spectral vegetation indices with fraction of absorbed PAR (fPAR) and quantum yield of chlorophyll fluorescence ( ΔF/ Fm') evidenced strongest relationships with the indices Normalized Difference Water Index (NDWI) and Photochemical Reflectance Index (PRI)512, respectively. Our results, while confirms the ability of spectral vegetation indices to represent temporal dynamics of biophysical properties of vegetation, evidence the importance to consider ecosystem composition for a correct ecological interpretation of results when the spatial resolution of observations includes different plant functional types.

  4. Dynamic surface soil components of land and vegetation types in Kebbi State Nigeria

    Suleiman Usman

    2016-04-01

    Full Text Available Land and vegetation are important components of soil and provides many benefits to surface soil including protection against erosion, climate change impact and unacceptable degradation of soil particles. Visual Soil Assessment was used as a mechanism to assess and classify the land and vegetation types of some agricultural sites in Kebbi State, Nigeria. The aim was to get better understanding of the environmental soil function for sustainable crop production in dryland and fadama areas of the State. The assessment was able to put together combinations of different vegetation types and land age classes. It is valued that the land age classes possessed the characteristics of Holocene-natural, Holocene-anthropogeomorphic, Holocene-young-natural, young-anthropogeomorphic, very-young anthropogeomorphic and very-young natural. However, the vegetation types could be related to evergreen forest, short medium forest (scattered clustered, dwarf vegetation (scattered isolated, grass vegetation, thick vegetation, stony-grass vegetation (scattered sparse and short-length vegetation. The assessment provides an improve understanding of the current status of land and vegetation conditions of the study area and suggested regular soil management for sustainable crop production in the State.

  5. Effects of vegetation type on soil microbial community structure and catabolic diversity assessed by polyphasic methods in North China

    2007-01-01

    Soil microbes play a major role in ecological processes and are closely associated with the aboveground plant community. In order to understand the effects of vegetation type on the characteristics of soil microbial communities, the soil microbial communities were assessed by plate counts, phospholipid fatty acid (PLFA) and Biolog microplate techniques in five plant communities, i.e., soybean field (SF), artificial turf (AT), artificial shrub (AS), natural shrub (NS), and maize field (MF) in Jinan, Shandong Province, North China. The results showed that plant diversity had little discernible effect on microbial biomass but a positive impact on the evennessof utilized substrates in Biolog microplate. Legumes could significantly enhance the number of cultural microorganisms, microbial biomass, and community catabolic diversity. Except for SF dominated by legumes, the biomass of fungi and the catabolic diversity of microbial community were higher in less disturbed soil beneath NS than in frequently disturbed soils beneath the other vegetation types. These results confirmed that high number of plant species, legumes, and natural vegetation types tend to support soil microbial communities with higher function. The present study also found a significant correlation between the number of cultured bacteria and catabolic diversity of the bacterial community. Different research methods led to varied results in this study. The combination of several approaches is recommended for accurately describing the characteristics of microbial communities in many respects.

  6. Ecological adaptation strategies of annual plants in artificial vegetation-stabilized sand dune in Shapotou Region

    ZHANG Jingguang; LI Xinrong; WANG Xinping; WANG Gang

    2004-01-01

    Taking annual plant Eragrostis poaeides in the artificial vegetation-stabilized sand dune in the Shapotou Experimental Research Station as example, study has been done on the adaptation strategies of annual plants to random environment through fixed quadrat observations of population changes and fixed plant determinations of individual growth, seed germination,population dynamics, spatial distribution pattern of population, competition and regulation. During the growing season, the survival rate of annual plants depends on the precipitation intensity and precipitation duration which activate the germination of seeds. The optimal germination strategy of annual plants in this habitat during the growing season appears as continuous germination under suitable conditions. Such continuous germination is an adaptive characteristic of annual plants to random environment. In addition, the variation processes of population size and regulation mechanism of E. poaeoides are studied. Statistical results of natural population in four consecutive years show that water condition in the habitat is the leading factor affecting the population dynamics of E. poaeoides. During the establishment period E. poaeoides had a higher death rate, but in the middle to later period they could survive stably. Due to the limitation of soil moisture, the competition among individuals for water inevitably led to self-thinning phenomena. Under very arid condition, the survival curve of annual herbs entirely appears as Deevey Ⅲ type (C type), but under relatively adequate precipitation condition, the survival curve appears as intermediate type. The strategy of life history obviously appears as r-strategy. Plant species of r-strategy often occurs in the early succession stage of the communities. In the relatively adequate and evenly-distributed rainfall years, E. poaeoides population exhibited a density-dependent, i. e., survival rate increased with decrease in population density. The main pattern to

  7. Water retention and evapotranspiration of green roofs and possible natural vegetation types

    Metselaar, K.

    2012-01-01

    Matching vegetation to growing conditions on green roofs is one of the options to increase biodiversity in cities. A hydrological model has been applied to match the hydrological requirements of natural vegetation types to roof substrate parameters and to simulate moisture stress for specific substr

  8. Radiation budget and soil heat fluxes in different Arctic tundra vegetation types

    Juszak, Inge; Iturrate Garcia, Maitane; Gastellu-Etchegorry, Jean-Philippe; Schaepman, Michael E.; Schaepman-Strub, Gabriela

    2016-04-01

    While solar radiation is one of the primary energy sources for warming and thawing permafrost soil, the amount of shortwave radiation reaching the soil is reduced by vegetation shading. Climate change has led to greening, shrub expansion and encroachment in many Arctic tundra regions and further changes are anticipated. These vegetation changes feed back to the atmosphere and permafrost as they modify the surface energy budget. However, canopy transmittance of solar radiation has rarely been measured or modelled for a variety of tundra vegetation types. We assessed the radiation budget of the most common vegetation types at the Kytalyk field site in North-East Siberia (70.8°N, 147.5°E) with field measurements and 3D radiative transfer modelling and linked it to soil heat fluxes. Our results show that Arctic tundra vegetation types differ in canopy albedo and transmittance as well as in soil heat flux and active layer thickness. Tussock sedges transmitted on average 56% of the incoming light and dwarf shrubs 27%. For wet sedges we found that the litter layer was very important as it reduced the average transmittance to only 6%. Model output indicated that both, albedo and transmittance, also depend on the spatial aggregation of vegetation types. We found that permafrost thaw was more strongly related to soil properties than to canopy shading. The presented radiative transfer model allows quantifying effects of the vegetation layer on the surface radiation budget in permafrost areas. The parametrised model can account for diverse vegetation types and variation of properties within types. Our results highlight small scale radiation budget and permafrost thaw variability which are indicated and partly caused by vegetation. As changes in species composition and biomass increase can influence thaw rates, small scale patterns should be considered in assessments of climate-vegetation-permafrost feedbacks.

  9. Quantifying the effectiveness of ecological restoration projects on long-term vegetation dynamics in the karst regions of Southwest China

    Tong, Xiaowei; Wang, Kelin; Yue, Yuemin; Brandt, Martin; Liu, Bo; Zhang, Chunhua; Liao, Chujie; Fensholt, Rasmus

    2017-02-01

    To alleviate the severe rocky desertification and improve the ecological degradation conditions in Southwest China, the national and local Chinese governments have implemented a series of Ecological Restoration Projects (ERPs) since the late 1990s. This study proposed a remote sensing based approach to evaluate the long-term efforts of the ERPs started in 2000. The method applies a time-series trend analysis of satellite based vegetation data corrected for climatic influences to reveal human induced vegetation changes. The improved residual method is combined with statistics on the invested project funds to derive an index, Project Effectiveness Index (PEI), measuring the project effectiveness at county scale. High effectiveness is detected in the Guangxi Province, moderate effectiveness in the Guizhou Province, and low and no effectiveness in the Yunnan Province. Successful implementations are closely related to the combined influences from climatic conditions and human management. The landforms of Peak Forest Plain and Peak Cluster Depression regions in the Guangxi Province are characterized by temperate climate with sufficient rainfall generally leading to a high effectiveness. For the karst regions of the Yunnan and Guizhou Provinces with rough terrain and lower rainfall combined with poor management practices (unsuitable species selection, low compensation rate for peasants), only low or even no effect of project implementations can be observed. However, the effectiveness distribution is not homogeneous and counties with high project effectiveness in spite of complex natural conditions were identified, while counties with negative vegetation trends despite relatively favorable conditions and high investments were also distinguished. The proposed framework is expected to be of high relevance in general monitoring of the successfulness of ecological conservation projects in relation to invested funds.

  10. Assessing Vegetation Cover Dynamics Induced by Policy-Driven Ecological Restoration and Implication to Soil Erosion in Southern China.

    Zhang, Jien; Wang, Tianming; Ge, Jianping

    2015-01-01

    In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how vegetation has changed in southern China since the launch of these programs. In this study, we used the MODIS Enhanced Vegetation Index (EVI) to analyze the vegetation cover dynamics in southern China from 2000 to 2009 and evaluate the resulting effects of controlling soil erosion. Our observations indicate that 5.3% of the study area significantly increased and 0.98% significantly decreased in EVI value (p soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River. This study displays the spatial patterns of trend in vegetation growth since the beginning of the 21st century in southern China and highlights the important role of China's afforestation program.

  11. Next-generation dynamic global vegetation models: learning from community ecology.

    Scheiter, Simon; Langan, Liam; Higgins, Steven I

    2013-05-01

    Dynamic global vegetation models (DGVMs) are powerful tools to project past, current and future vegetation patterns and associated biogeochemical cycles. However, most models are limited by how they define vegetation and by their simplistic representation of competition. We discuss how concepts from community assembly theory and coexistence theory can help to improve vegetation models. We further present a trait- and individual-based vegetation model (aDGVM2) that allows individual plants to adopt a unique combination of trait values. These traits define how individual plants grow and compete. A genetic optimization algorithm is used to simulate trait inheritance and reproductive isolation between individuals. These model properties allow the assembly of plant communities that are adapted to a site's biotic and abiotic conditions. The aDGVM2 simulates how environmental conditions influence the trait spectra of plant communities; that fire selects for traits that enhance fire protection and reduces trait diversity; and the emergence of life-history strategies that are suggestive of colonization-competition trade-offs. The aDGVM2 deals with functional diversity and competition fundamentally differently from current DGVMs. This approach may yield novel insights as to how vegetation may respond to climate change and we believe it could foster collaborations between functional plant biologists and vegetation modellers.

  12. Vegetation and Vertebrates of the Patuxent Wildlife Research Center, Outline of Ecology and Annotated Lists 1947

    US Fish and Wildlife Service, Department of the Interior — This is an extensive list of vegetation and vertebrates at the Patuxent Wildlife Research Center based on information gathered during the years 1936-1946.

  13. Ecological optimality in water-limited natural soil-vegetation systems. II - Tests and applications

    Eagleson, P. S.; Tellers, T. E.

    1982-01-01

    The long-term optimal climatic climax soil-vegetation system is defined for several climates according to previous hypotheses in terms of two free parameters, effective porosity and plant water use coefficient. The free parameters are chosen by matching the predicted and observed average annual water yield. The resulting climax soil and vegetation properties are tested by comparison with independent observations of canopy density and average annual surface runoff. The climax properties are shown also to satisfy a previous hypothesis for short-term optimization of canopy density and water use coefficient. Using these hypotheses, a relationship between average evapotranspiration and optimum vegetation canopy density is derived and is compared with additional field observations. An algorithm is suggested by which the climax soil and vegetation properties can be calculated given only the climate parameters and the soil effective porosity. Sensitivity of the climax properties to the effective porosity is explored.

  14. Using Dehydrated Vegetables in Some Brown Bread Types

    Simona Man

    2013-11-01

    Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 Expanding the range of bakery products in terms of producing supplemented or dietetic products has been an increasingly important trend in contemporary baking. Bakery products as basic and popular food, could be used in the prevention of nutritive deficiencies of many important nutrients, by supplementing the products with biologically valuable ingredients. Such ingredients are dehydrated vegetables in the form of powder. For establishing the bread quality, a special importance shows it’s chemical composition, because the substances that enter in it’s constitution serve to obtaining the energy necessary to the human body. Beside the chemical composition, the bread quality and alimentary use, respectively, depends a large measure on a series of signs: flavor and taste, external appearance, crumb porosity and texture, breads’ volume. This paper belongs to a more complex study, which aims are obtaining some bread assortments with high nutritional value, and improving their sensorial and rheological features, by adding dehydrated vegetables at different levels 4% potato flakes, 2% dehydrated onion, 0.5% dehydrated garlic and 2% dehydrated leek.

  15. Survey of the terrestrial habitats and vegetation of Shetland, 1974 - a framework for long-term ecological monitoring

    Wood, Claire M.; Bunce, Robert G. H.

    2016-02-01

    A survey of the natural environment was undertaken in Shetland in 1974, after concern was expressed that large-scale development from the new oil industry could threaten the natural features of the islands. A framework was constructed by the Institute of Terrestrial Ecology on which to select samples for the survey. The vegetation and habitat data that were collected, along with the sampling framework, have recently been made public via the following doi:10.5285/06fc0b8c-cc4a-4ea8-b4be-f8bd7ee25342 (Terrestrial habitat, vegetation and soil data from Shetland, 1974) and doi:10.5285/f1b3179e-b446-473d-a5fb-4166668da146 (Land Classification of Shetland 1974). In addition to providing valuable information about the state of the natural environment of Shetland, the repeatable and statistically robust methods developed in the survey were used to underpin the Countryside Survey, Great Britain's national long-term integrated environmental monitoring programme. The demonstration of the effectiveness of the methodology indicates that a repeat of the Shetland survey would yield statistics about ecological changes in the islands, such as those arising from the impacts of the oil industry, a range of socio-economic impacts, and perhaps climate change. Currently no such figures are available, although there is much information on the sociological impacts, as well as changes in agriculture.

  16. Survey of the terrestrial habitats and vegetation of Shetland, 1974 - a framework for long term ecological monitoring

    Wood, C. M.; Bunce, R. G. H.

    2015-10-01

    A survey of the natural environment was undertaken in Shetland in 1974, after concern was expressed that large scale development from the new oil industry could threaten the natural features of the islands. A framework was constructed by the Institute of Terrestrial Ecology on which to select samples for the survey. The vegetation and habitat data that were collected, along with the sampling framework, have recently been made public via the following DOIs: doi:10.5285/06fc0b8c-cc4a-4ea8-b4be-f8bd7ee25342 (Terrestrial habitat, vegetation and soil data from Shetland, 1974) and doi:10.5285/f1b3179e-b446-473d-a5fb-4166668da146 (Land Classification of Shetland 1974). In addition to providing valuable information about the state of the natural environment of Shetland, the repeatable and statistically robust methods developed in the survey were used to underpin the Countryside Survey, Great Britain's national long-term integrated environmental monitoring programme. The demonstration of the effectiveness of the methodology indicates that a repeat of the survey would yield statistics about ecological changes in the islands, such as those arising from the impacts of the oil industry. Currently no such figures are available although there is much information on the sociological impacts, as well as changes in agriculture.

  17. Analysis of ecological context for identifying vegetation and animal conservation planning foci: An example from the arid South-western USA

    Hamazaki, T.; Thompson, B.C.; Locke, B.A.; Boykin, K.G.

    2003-01-01

    In developing conservation strategies, it is important to maximize effects of conservation within a specified land tract and to maximize conservation effects on surrounding area (ecological context). The authors proposed two criteria to select biotic entities for conservation foci: (1) the relative occurrence of fauna or flora in a tract is greater than that of an ecological context region; and (2) occurrence of the fauna or flora is relatively limited in the ecological context region. Using extensive spatial data on vegetation and wildlife habitat distribution, the authors identified strategic vegetation and fauna conservation foci for the 400 000 ha Fort Bliss military reservation in New Mexico and Texas relative to a 164 km radius ecological context region intersecting seven ecological zones and the predicted habitat distribution of 616 animal species. The authors set two specific criteria: (1) predicted area of a species' occurrence is 5% (Fort Bliss is 4.2% of the region). These criteria selected one vegetation class and 40 animal species. Further, these vegetation and animal foci were primarily located in two areas of Fort Bliss. Sensitivity analyses with other analytical radii corroborated the context radius used. Conservation of the two areas and associated taxa will maximize the contribution of Fort Bliss's conservation efforts in its ecological proximity. This relatively simple but information-rich process represents economical and defensible preliminary contextual analysis for detailed conservation planning.

  18. Major vegetation types, climatological data, and solar radiation calculations for Colorado's Brush Creek valley

    Whiteman, C.D.; Lambeth, R.; Allwine, K.J.

    1987-04-01

    In this report we present information on the vegetative cover, climate, and solar radiation for the Brush Creek valley. A brief vegetative survey was made on October 3, 1984, to identify the vegetation types in the lowest 8 km of the valley; the reader is cautioned that this included only a small part of the Brush Creek valley. The intent was to identify the principal vegetation types, with no attempt to use available scientific sampling techniques to determine accurate relative frequencies of the vegetation types. Nevertheless, the site survey has allowed us to identify the major species of vegetation, and to make reasonably accurate differentiations of both major vegetation types on valley surfaces (the valley floor, two sidewalls, and ridgetops) and the relative abundance of major vegetation types on each surface.

  19. Aquatic vegetation in response to increased eutrophication and degraded light climate in Eastern Lake Taihu: Implications for lake ecological restoration

    Zhang, Yunlin; Liu, Xiaohan; Qin, Boqiang; Shi, Kun; Deng, Jianming; Zhou, Yongqiang

    2016-04-01

    Terrestrial and aquatic ecosystem degradation is widely recognized as a major global environmental and development problem. Although great efforts have been made to prevent aquatic ecosystem degradation, the degree, extent and impacts of this phenomenon remain controversial and unclear, such as its driving mechanisms. Here, we present results from a 17-year field investigation (1998-2014) of water quality and a 12-year remote sensing mapping (2003-2014) of the aquatic vegetation presence frequency (VPF) in Eastern Lake Taihu, a macrophyte-dominated bay of Lake Taihu in China. In the past 17 years, nutrient concentrations and water level (WL) have significantly increased, but the Secchi disk depth (SDD) has significantly decreased. These changes were associated with increased lake eutrophication and a degraded underwater light climate that further inhibited the growth of aquatic vegetation. In Eastern Lake Taihu, increased nutrients, chlorophyll a and WL, and a decreased SDD were all significantly correlated with a decreased VPF. NH4+-N concentration and SDD/WL were the most important controlling factors for VPF. Therefore, increased anthropogenic nutrient inputs and a degraded underwater light climate surely result in a decreased VPF. These results elucidate the driving mechanism of aquatic vegetation degradation and will facilitate Lake Taihu ecological restoration.

  20. 生态景观型灌排系统面源污染防治试验及生态响应%Non-point source pollution control experiment and ecological response of ecological landscape type irrigation and drainage system

    张雅杰; 邵庆军; 李海彩; 叶梁倩; 姚星; 胡将军

    2015-01-01

    The current irrigation and drainage system in land renovation was mainly designed and constructed to heighten efficiency of irrigation and drainage, structure safety and convenient management, which, however, somewhat neglected ecological landscape design, exerting an inappropriate influence on the biological habitat and agricultural non-point source pollution. Therefore, the aim of this paper is to design an ecological landscape irrigation and drainage system and realize more comprehensive benefits. First of all, originated from the traditional agricultural drainage and irrigation system, irrigation and drainage with an ecological ring-ditch was designed by using the principle of mutually-beneficial symbiosis of paddy, red duckweed, fish and vegetable planting plates, which realized the multifunctional stereo development of rice paddy pisciculture, vegetable planting and so on. Meanwhile, the roundabout biochemical pond was designed at the ecological ring-ditch drainage sluice, which was used as the treatment device of agricultural non-point source pollution. Then, ecological landscape lateral canal and lateral ditch was designed, which was made up of vegetation type diaphragm blocks, hornworts, vegetable planting plates, fish, Jumping type antiskid ecological plate and plant ecological community. What is more, by using the land reclamation project in shanghai as the experimental area, the rice growth cycle (6-10 months) as study period, the COD, NH4+-N, TN and TP as test indicators, and three monitoring sections as monitoring points, experimental of non-point source pollution prevention effects were made comparisons between system 1, system 2 and system3. The system 1 was constituted by the irrigation and drainage system using ecological ring-ditch, roundabout biochemical pond and lateral ditch wetlands. The system 2 was constituted by the irrigation and drainage system using underground pipe and current lateral ditch. And the system 3 was constituted by the

  1. Divergent Impacts of Two Cattle Types on Vegetation in Coastal Meadows: Implications for Management.

    Laurila, Marika; Huuskonen, Arto; Pesonen, Maiju; Kaseva, Janne; Joki-Tokola, Erkki; Hyvärinen, Marko

    2015-11-01

    The proportion of beef cattle in relation to the total number of cattle has increased in Europe, which has led to a higher contribution of beef cattle in the management of semi-natural grasslands. Changes in vegetation caused by this change in grazers are virtually unexplored so far. In the present study, the impacts of beef and dairy cattle on vegetation structure and composition were compared on Bothnian Bay coastal meadows. Vegetation parameters were measured in seven beef cattle, six dairy heifer pastures, and in six unmanaged meadows. Compared to unmanaged meadows, vegetation in grazed meadows was significantly lower in height and more frequently colonized by low-growth species. As expected, vegetation grazed by beef cattle was more open than that on dairy heifer pastures where litter cover and proportion of bare ground were in the same level as in the unmanaged meadows. However, the observed differences may have in part arisen from the higher cattle densities in coastal meadows grazed by beef cattle than by dairy heifers. The frequencies of different species groups and the species richness values of vegetation did not differ between the coastal meadows grazed by the two cattle types. One reason for this may be the relatively short management history of the studied pastures. The potential differences in grazing impacts of the two cattle types on vegetation structure can be utilized in the management of coastal meadows for species with divergent habitat requirements.

  2. Simulation of maximum light use efficiency for some typical vegetation types in China

    2006-01-01

    Maximum light use efficiency (εmax) is a key parameter for the estimation of net primary productivity (NPP) derived from remote sensing data. There are still many divergences about its value for each vegetation type. The εmax for some typical vegetation types in China is simulated using a modified least squares function based on NOAA/AVHRR remote sensing data and field-observed NPP data. The vegetation classification accuracy is introduced to the process. The sensitivity analysis of εmax to vegetation classification accuracy is also conducted. The results show that the simulated values of εmax are greater than the value used in CASA model, and less than the values simulated with BIOME-BGC model. This is consistent with some other studies. The relative error of εmax resulting from classification accuracy is -5.5%―8.0%. This indicates that the simulated values of εmax are reliable and stable.

  3. Regenerating degraded soils and increasing water use efficiency on vegetable farms in Uruguay through ecological intensification

    Alliaume, F.

    2016-01-01

    This thesis investigated alternative soil management strategies for vegetable crop systems and their hypothesized effects on increasing systems resilience by sequestering soil carbon, increasing the efficiency of water use, and reducing erosion. The goal was to contribute knowledge on and tools for

  4. The vegetation ecology of the Eastern Transvaal Escarpment in the Sabie area. 1. Physical environment

    Gillian B. Deall

    1989-12-01

    Full Text Available The physiography, geology, soil and climate of a broad transect of the Eastern Transvaal Escarpment in the Sabie area are described. The transect extends from Hazyview (530 m elevation to Mount Anderson (2 280 m elevation. The description provides a contextual framework for the subsequent vegetation classification.

  5. VEGETATION MAPPING IN WETLANDS

    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.

  6. Asymmetric ecological conditions favor Red-Queen type of continued evolution over stasis.

    Nordbotten, Jan Martin; Stenseth, Nils C

    2016-02-16

    Four decades ago, Leigh Van Valen presented the Red Queen's hypothesis to account for evolution of species within a multispecies ecological community [Van Valen L (1973) Evol Theory 1(1):1-30]. The overall conclusion of Van Valen's analysis was that evolution would continue even in the absence of abiotic perturbations. Stenseth and Maynard Smith presented in 1984 [Stenseth NC, Maynard Smith J (1984) Evolution 38(4):870-880] a model for the Red Queen's hypothesis showing that both Red-Queen type of continuous evolution and stasis could result from a model with biotically driven evolution. However, although that contribution demonstrated that both evolutionary outcomes were possible, it did not identify which ecological conditions would lead to each of these evolutionary outcomes. Here, we provide, using a simple, yet general population-biologically founded eco-evolutionary model, such analytically derived conditions: Stasis will predominantly emerge whenever the ecological system contains only symmetric ecological interactions, whereas both Red-Queen and stasis type of evolution may result if the ecological interactions are asymmetrical, and more likely so with increasing degree of asymmetry in the ecological system (i.e., the more trophic interactions, host-pathogen interactions, and the like there are [i.e., +/- type of ecological interactions as well as asymmetric competitive (-/-) and mutualistic (+/+) ecological interactions]). In the special case of no between-generational genetic variance, our results also predict dynamics within these types of purely ecological systems.

  7. [Reproductive phenology of three vegetation types from a coastal plain of Paraguana Penninsula, Venezuela].

    Lemus-Jiménez, Luis José; Ramírez, Nelson

    2002-01-01

    Reproductive phenology of 51 plant species was evaluated according to life form and vegetation types in a coastal plain of the Paraguaná Peninsula, Estado Falcón, Venezuela. Plant species distribution according to three vegetation types (herbaceous littoral, herbaceous psamophil, and mangrove area) was determined. Life form frequency was different according to vegetation type. Herbaceous littoral and herbaceous psamophil vegetation were dominated by herbaceous species; woody species were mostly frequent in the mangrove vegetation. Phenological data revealed that 14 (27.5%) plant species flower and fruit year-round; 23 (45.1%) plant species flower and fruit at the beginning of the wet season; seven (13.7%) plant species flower at the end of wet season, and seven (13.7%) more flower at the beginning of the dry season. Flowsring and fruiting phenology showed similar frequency distribution during the year; reproductive phenology was independent of life forms. Flowering and fruiting peaks occurred during the rainy season and the beginning of the dry season for trees and perennial herbs, and from one to three months later for shrubs and annual herbs. The lowest proportion of flowering and fruiting occurred before rain increase for all life forms. Flowering and fruiting phenologies were similar for the three vegetation types evaluated: flowering peak occurred during the lowest value of precipitation, three to four months after precipitation peak, and fruiting peak occurred four months later from the precipitation peak. These results suggest that flowering and fruiting phenology were not affected by life form and vegetation types. The peaks of flowering and fruiting during the lowest values of precipitation may be considered as a slow and late response to the precipitation maximum, and to the proximity between maximum and minimum of precipitation.

  8. Monitoring of fire incidences in vegetation types and Protected Areas of India: Implications on carbon emissions

    Reddy, C. Sudhakar; Padma Alekhya, V. V. L.; Saranya, K. R. L.; Athira, K.; Jha, C. S.; Diwakar, P. G.; Dadhwal, V. K.

    2017-02-01

    Carbon emissions released from forest fires have been identified as an environmental issue in the context of global warming. This study provides data on spatial and temporal patterns of fire incidences, burnt area and carbon emissions covering natural vegetation types (forest, scrub and grassland) and Protected Areas of India. The total area affected by fire in the forest, scrub and grasslands have been estimated as 48765.45, 6540.97 and 1821.33 km 2, respectively, in 2014 using Resourcesat-2 AWiFS data. The total CO 2 emissions from fires of these vegetation types in India were estimated to be 98.11 Tg during 2014. The highest emissions were caused by dry deciduous forests, followed by moist deciduous forests. The fire season typically occurs in February, March, April and May in different parts of India. Monthly CO 2 emissions from fires for different vegetation types have been calculated for February, March, April and May and estimated as 2.26, 33.53, 32.15 and 30.17 Tg, respectively. Protected Areas represent 11.46% of the total natural vegetation cover of India. Analysis of fire occurrences over a 10-year period with two types of sensor data, i.e., AWiFS and MODIS, have found fires in 281 (out of 614) Protected Areas of India. About 16.78 Tg of CO 2 emissions were estimated in Protected Areas in 2014. The natural vegetation types of Protected Areas have contributed for burnt area of 17.3% and CO 2 emissions of 17.1% as compared to total natural vegetation burnt area and emissions in India in 2014. 9.4% of the total vegetation in the Protected Areas was burnt in 2014. Our results suggest that Protected Areas have to be considered for strict fire management as an effective strategy for mitigating climate change and biodiversity conservation.

  9. Monitoring of fire incidences in vegetation types and Protected Areas of India: Implications on carbon emissions

    C Sudhakar Reddy; V V L Padma Alekhya; K R L Saranya; K Athira; C S Jha; P G Diwakar; V K Dadhwal

    2017-02-01

    Carbon emissions released from forest fires have been identified as an environmental issue in the context of global warming. This study provides data on spatial and temporal patterns of fire incidences, burnt area and carbon emissions covering natural vegetation types (forest, scrub and grassland) and Protected Areas of India. The total area affected by fire in the forest, scrub and grasslands have been estimated as 48765.45, 6540.97 and 1821.33 km², respectively, in 2014 using Resourcesat-2 AWiFS data. The total CO₂ emissions from fires of these vegetation types in India were estimated to be 98.11 Tg during 2014. The highest emissions were caused by dry deciduous forests, followed by moist deciduous forests. The fire season typically occurs in February, March, April and May in different parts of India. Monthly CO₂ emissions from fires for different vegetation types have been calculated for February, March, April and May and estimated as 2.26, 33.53, 32.15 and 30.17 Tg, respectively. Protected Areas represent 11.46% of the total natural vegetation cover of India. Analysis of fire occurrences over a 10-year period with two types of sensor data, i.e., AWiFS and MODIS, have found fires in 281 (out of 614) Protected Areas of India. About 16.78 Tg of CO₂ emissions were estimated in Protected Areas in 2014. The natural vegetation types of Protected Areas have contributed for burnt area of 17.3% and CO₂ emissions of 17.1% as compared to total natural vegetation burnt area and emissions in India in 2014. 9.4% of the total vegetation in the Protected Areas was burnt in 2014. Our results suggest that Protected Areas have to be considered for strict fire management as an effective strategy for mitigating climate change and biodiversity conservation.

  10. Arctic Tundra Vegetation Functional Types Based on Photosynthetic Physiology and Optical Properties

    Huemmrich, Karl Fred; Gamon, John A.; Tweedie, Craig E.; Campbell, Petya K. Entcheva; Landis, David R.; Middleton, Elizabeth M.

    2013-01-01

    Non-vascular plants (lichens and mosses) are significant components of tundra landscapes and may respond to climate change differently from vascular plants affecting ecosystem carbon balance. Remote sensing provides critical tools for monitoring plant cover types, as optical signals provide a way to scale from plot measurements to regional estimates of biophysical properties, for which spatial-temporal patterns may be analyzed. Gas exchange measurements were collected for pure patches of key vegetation functional types (lichens, mosses, and vascular plants) in sedge tundra at Barrow, AK. These functional types were found to have three significantly different values of light use efficiency (LUE) with values of 0.013 plus or minus 0.0002, 0.0018 plus or minus 0.0002, and 0.0012 plus or minus 0.0001 mol C mol (exp -1) absorbed quanta for vascular plants, mosses and lichens, respectively. Discriminant analysis of the spectra reflectance of these patches identified five spectral bands that separated each of these vegetation functional types as well as nongreen material (bare soil, standing water, and dead leaves). These results were tested along a 100 m transect where midsummer spectral reflectance and vegetation coverage were measured at one meter intervals. Along the transect, area-averaged canopy LUE estimated from coverage fractions of the three functional types varied widely, even over short distances. The patch-level statistical discriminant functions applied to in situ hyperspectral reflectance data collected along the transect successfully unmixed cover fractions of the vegetation functional types. The unmixing functions, developed from the transect data, were applied to 30 m spatial resolution Earth Observing-1 Hyperion imaging spectrometer data to examine variability in distribution of the vegetation functional types for an area near Barrow, AK. Spatial variability of LUE was derived from the observed functional type distributions. Across this landscape, a

  11. Soil data for a vegetation gradient located at Bonanza Creek Long Term Ecological Research Site, interior Alaska

    Manies, Kristen L.; Harden, Jennifer W.; Fuller, Christopher C.; Xu, Xiaomei; McGeehin, John P.

    2016-07-28

    Boreal soils play an important role in the global carbon cycle owing to the large amount of carbon stored within this northern region. To understand how carbon and nitrogen storage varied among different ecosystems, a vegetation gradient was established in the Bonanza Creek Long Term Ecological Research (LTER) site, located in interior Alaska. The ecosystems represented are a black spruce (Picea mariana)–feather moss (for example, Hylocomium sp.) forest ecosystem, a shrub-dominated ecosystem, a tussock-grass-dominated ecosystem, a sedge-dominated ecosystem, and a rich fen ecosystem. Here, we report the physical, chemical, and descriptive properties for the soil cores collected at these sites. These data have been used to calculate carbon and nitrogen accumulation rates on a long-term (decadal and century) basis (Manies and others, in press).

  12. Soil Respiration Responses to Variation in Temperature Treatment and Vegetation Type

    Liu, S.; Pavao-zuckerman, M.

    2013-12-01

    Complex linkages exist between terrestrial vegetation, soil moisture, soil organic matter (SOM), local climate, and soil microorganisms. Thus, large-scale changes in vegetation, such as the woody plant encroachment observed in many historically semiarid and arid grasslands worldwide, could potentially alter the flux of carbon from soil reserves to the atmosphere. Mathematical models that attempt to project the long-term impact of vegetative shifts on soil fluxes largely rely on assumptions such as first-order donor control rather than incorporate the biological aspects of soil respiration such as microbial activity. To examine the impact of vegetation type on soil physicochemical properties and soil microbial respiration and provide experimental data to refine existing predictive models, we compared soil (ground basalt from northern Arizona) in mesocosms established with no vegetation, velvet mesquites (Prosopis velutina; woody shrub), or sideoats gramas (Bouteloua curtipendula; grass) for 2 years, The temperature sensitivity of soil respiration was examined by incubating soil (0-10 and 10-30 cm depth fractions) from each vegetation treatment at 10, 20, 30, and 40 °C for 24 hours. Vegetated soils contained more SOM (~0.1% for mesquite and grass mesocosms) than non-vegetated soils (~0.02%). Respiration rates were generally highest from grass-established soils, intermediate from mesquite-established soils, and lowest from non-vegetated soils. Respiration rates of samples incubated without the addition of substrate peaked at approximately 30 °C, whereas respiration rates of samples incubated with dextrose were highest at 40 °C. Further, the respiration assays suggest that while respiration rates are overall higher in grass-established soils, mesquite-established soils are more temperature sensitive which may have significant implications in the context of global warming and current fire management practices.

  13. Vegetation Impact and Recovery from Oil-Induced Stress on Three Ecologically Distinct Wetland Sites in the Gulf of Mexico

    Kristen Shapiro

    2016-05-01

    Full Text Available April 20, 2010 marked the start of the British Petroleum Deepwater Horizon oil spill, the largest marine oil spill in US history, which contaminated coastal wetland ecosystems across the northern Gulf of Mexico. We used hyperspectral data from 2010 and 2011 to compare the impact of oil contamination and recovery of coastal wetland vegetation across three ecologically diverse sites: Barataria Bay (saltmarsh, East Bird’s Foot (intermediate/freshwater marsh, and Chandeleur Islands (mangrove-cordgrass barrier islands. Oil impact was measured by comparing wetland pixels along oiled and oil-free shorelines using various spectral indices. We show that the Chandeleur Islands were the most vulnerable to oiling, Barataria Bay had a small but widespread and significant impact, and East Bird’s Foot had negligible impact. A year later, the Chandeleur Islands showed the strongest signs of recovery, Barataria Bay had a moderate recovery, and East Bird’s Foot had only a slight increase in vegetation. Our results indicate that the recovery was at least partially related to the magnitude of the impact such that greater recovery occurred at sites that had greater impact.

  14. Spreading topsoil encourages ecological restoration on embankments: soil fertility, microbial activity and vegetation cover.

    Rivera, Desirée; Mejías, Violeta; Jáuregui, Berta M; Costa-Tenorio, Marga; López-Archilla, Ana Isabel; Peco, Begoña

    2014-01-01

    The construction of linear transport infrastructure has severe effects on ecosystem functions and properties, and the restoration of the associated roadslopes contributes to reduce its impact. This restoration is usually approached from the perspective of plant cover regeneration, ignoring plant-soil interactions and the consequences for plant growth. The addition of a 30 cm layer of topsoil is a common practice in roadslope restoration projects to increase vegetation recovery. However topsoil is a scarce resource. This study assesses the effects of topsoil spreading and its depth (10 to 30 cm) on two surrogates of microbial activity (β-glucosidase and phosphatase enzymes activity and soil respiration), and on plant cover, plant species richness and floristic composition of embankment vegetation. The study also evaluates the differences in selected physic-chemical properties related to soil fertility between topsoil and the original embankment substrate. Topsoil was found to have higher values of organic matter (11%), nitrogen (44%), assimilable phosphorous (50%) and silt content (54%) than the original embankment substrate. The topsoil spreading treatment increased microbial activity, and its application increased β-glucosidase activity (45%), phosphatase activity (57%) and soil respiration (60%). Depth seemed to affect soil respiration, β-glucosidase and phosphatase activity. Topsoil application also enhanced the species richness of restored embankments in relation to controls. Nevertheless, the depth of the spread topsoil did not significantly affect the resulting plant cover, species richness or floristic composition, suggesting that both depths could have similar effects on short-term recovery of the vegetation cover. A significant implication of these results is that it permits the application of thinner topsoil layers, with major savings in this scarce resource during the subsequent slope restoration work, but the quality of topsoil relative to the

  15. Spreading topsoil encourages ecological restoration on embankments: soil fertility, microbial activity and vegetation cover.

    Desirée Rivera

    Full Text Available The construction of linear transport infrastructure has severe effects on ecosystem functions and properties, and the restoration of the associated roadslopes contributes to reduce its impact. This restoration is usually approached from the perspective of plant cover regeneration, ignoring plant-soil interactions and the consequences for plant growth. The addition of a 30 cm layer of topsoil is a common practice in roadslope restoration projects to increase vegetation recovery. However topsoil is a scarce resource. This study assesses the effects of topsoil spreading and its depth (10 to 30 cm on two surrogates of microbial activity (β-glucosidase and phosphatase enzymes activity and soil respiration, and on plant cover, plant species richness and floristic composition of embankment vegetation. The study also evaluates the differences in selected physic-chemical properties related to soil fertility between topsoil and the original embankment substrate. Topsoil was found to have higher values of organic matter (11%, nitrogen (44%, assimilable phosphorous (50% and silt content (54% than the original embankment substrate. The topsoil spreading treatment increased microbial activity, and its application increased β-glucosidase activity (45%, phosphatase activity (57% and soil respiration (60%. Depth seemed to affect soil respiration, β-glucosidase and phosphatase activity. Topsoil application also enhanced the species richness of restored embankments in relation to controls. Nevertheless, the depth of the spread topsoil did not significantly affect the resulting plant cover, species richness or floristic composition, suggesting that both depths could have similar effects on short-term recovery of the vegetation cover. A significant implication of these results is that it permits the application of thinner topsoil layers, with major savings in this scarce resource during the subsequent slope restoration work, but the quality of topsoil relative to

  16. THE FORMATION OF ENTS ADAPTIVE REACTIONS DEPENDING ON THE TYPE OF PSYCHO-VEGETATIVE REGULATION

    E. M. Kazin

    2014-01-01

    Full Text Available The purpose of the students (12 to 15 years old examination was to identify the integrative criteria of assessing the nature of the functional relationships between the parameters of the psychosocial and physiological adaptation of students, depending on age, individual-typological peculiarities of vegetative regulation, personal potential at different stages of school education.The study of the characteristics of vegetative regulation of the cardiovascular system was made with a help of an automatic cardiac-rhythm programs. The research of psychophysiological parameters was fulfiled using an automatic complex. The measurement of the speed of simple visual-motor reaction (PSMR, reaction to a moving object (WFD, the level of functional mobility of nervous processes (WFP and health brain (DDM were made before. Features psychosocial adaptation was analyzed using 8-color Luscher test.All examinee were divided into three groups on the basis of the statistical characteristics of the cardiac rhythm by the tone source autonomic tone: “vagotonia” (with a predominance of parasympathetic sistems, “somatotonic” (with domination of the sympatholytic effects, “atonic” (balanced type of vegetative nervous system.Based on the analysis of psychodynamic, neurodynamic and vegetative functions showed that students with initial vagotonies tone are characterized by high levels of situational and personal anxiety, low psychosocial adaptation, decreased activity of neurodynamic functions and psychodynamic processes in the learning dynamics, whereas the individuals with dominance of sympatotonics type regulation have high level of neurodynamic processes, psychosocial adaptation, against the background of significant stress mechanisms of vegetative regulation.Students with initial vegetative tone demonstrate a sufficient level of psychosocial adaptation, activity psychodynamic and neuromotor processes, accompanied by the preservation of the functionality of

  17. Effects of Spatial Heterogeneity in Rainfall and Vegetation Type on Soil Moisture and Evapotranspiration

    Puma, Michael J; Rodriguez-Iturbe, Ignacio; Nordbotten, Jan M; Guswa, Andrew J; Kavetski, Dmitri

    2016-01-01

    Nonlinear plant-scale interactions controlling the soil-water balance are generally not valid at larger spatial scales due to spatial heterogeneity in rainfall and vegetation type. The relationships between spatially averaged variables are hysteretic even when unique relationships are imposed at the plant scale. The characteristics of these hysteretic relationships depend on the size of the averaging area and the spatial properties of the soil, vegetation, and rainfall. We upscale the plant-scale relationships to the scale of a regional land-surface model based on simulation data obtained through explicit representation of spatial heterogeneity in rainfall and vegetation type. The proposed upscaled function improves predictions of spatially averaged soil moisture and evapotranspiration relative to the effective-parameter approach for a water-limited Texas shrubland. The degree of improvement is a function of the scales of heterogeneity and the size of the averaging area. We also find that single-valued functi...

  18. Vegetation ecological restoration during geothermic exploratory perforation: A case study in Mexico

    Ortega-Rubio, A.; Salinas, F.; Naranjo, A. [and others

    1997-12-31

    At Las Tres Virgenes, B.C.S., Mexico developed the Geothermic exploratory drilling of the area. One of the main recommendations of our Environmental Impact Assessment Study includes transplantation of the plant individuals found in the zones of roads and drilling platforms. In this work we describe the methodologies used to transplant the vegetal individuals found in such zones. We listed the species selected and the survivorship rate obtained for every one of them. From a total of 4,266 transplanted individuals, including many endemic species, a total of 2349 survived. Members of the Agavaceae and Cactaceae families show the maximum survivorship rate, meanwhile the members of the Burseraceae, Euphorbiaceae and Fouqueriaceae families exhibited the minimum survivorship rate (between 12.7% and 20%).

  19. On the delineation of tropical vegetation types with an emphasis on forest/savanna transitions

    Torello-Raventos, M.; Feldpausch, T.R.; Veenendaal, E.M.; Sykora, K.V.

    2013-01-01

    Background: There is no generally agreed classification scheme for the many different vegetation formation types occurring in the tropics. This hinders cross-continental comparisons and causes confusion as words, such as ‘forest’ and ‘savanna’ have different meanings to different people. Tropical ve

  20. Plant community and ecological analysis of woodland vegetation in Metema Area, Amhara National Regional State, Northwestern Ethiopia

    Haile Adamu Wale; Tamrat Bekele; Gemedo Dalle

    2012-01-01

    We studied woodland vegetation in broad-leaved deciduous woodlands of Metema in northwestern Amhara regional state,Ethiopia to determine plant community types and species distribution patterns and their relationships with environmental variables,including altitude,pH,cation exchange capacity,electrical conductivity (EC),and moisture.We used a selective approach with a systematic sampling design.A total of 74 quadrats,each 25m × 25m at intervals of 150-200 m were sampled along the established transect lines.For herbaceous vegetation and soil data collection,five subquadrats each 1m × 1m were established at the four corners and the center of each quadrat.Three community types were identified using TWINSPAN analysis.All three community types showed high diversity (Shannon-Weiner index),the highest in community type Ⅱ at 3.55.The highest similarity coefficient was 0.49 (49%) between community types Ⅱ and Ⅲ,reflecting 0.51 (51%) dissimilarity in their species richness.The canonical correspondence ordination diagram revealed that the distribution pattern of community type Ⅰ was explained by moisture while that of community types Ⅲ and Ⅱ was explained by EC and altitude and moisture,respectively.Altitude was the most statistically significant environmental variable,followed by moisture and EC in determining the total variation in species composition and distribution patterns while pH and cation exchange capacity were non significant.In conclusion,we recommend that any intervention should take into account these three discrete community types and their environmental settings to make the intervention more successful.

  1. Soil and vegetation carbon stocks in Brazilian Western Amazonia: relationships and ecological implications for natural landscapes.

    Schaefer, C E G R; do Amaral, E F; de Mendonça, B A F; Oliveira, H; Lani, J L; Costa, L M; Fernandes Filho, E I

    2008-05-01

    The relationships between soils attributes, soil carbon stocks and vegetation carbon stocks are poorly know in Amazonia, even at regional scale. In this paper, we used the large and reliable soil database from Western Amazonia obtained from the RADAMBRASIL project and recent estimates of vegetation biomass to investigate some environmental relationships, quantifying C stocks of intact ecosystem in Western Amazonia. The results allowed separating the western Amazonia into 6 sectors, called pedo-zones: Roraima, Rio Negro Basin, Tertiary Plateaux of the Amazon, Javari-Juruá-Purus lowland, Acre Basin and Rondonia uplands. The highest C stock for the whole soil is observed in the Acre and in the Rio Negro sectors. In the former, this is due to the high nutrient status and high clay activity, whereas in the latter, it is attributed to a downward carbon movement attributed to widespread podzolization and arenization, forming spodic horizons. The youthful nature of shallow soils of the Javari-Juruá-Purus lowlands, associated with high Al, results in a high phytomass C/soil C ratio. A similar trend was observed for the shallow soils from the Roraima and Rondonia highlands. A consistent east-west decline in biomass carbon in the Rio Negro Basin sector is associated with increasing rainfall and higher sand amounts. It is related to lesser C protection and greater C loss of sandy soils, subjected to active chemical leaching and widespread podzolization. Also, these soils possess lower cation exchangeable capacity and lower water retention capacity. Zones where deeply weathered Latosols dominate have a overall pattern of high C sequestration, and greater than the shallower soils from the upper Amazon, west of Madeira and Negro rivers. This was attributed to deeper incorporation of carbon in these clayey and highly pedo-bioturbated soils. The results highlight the urgent need for refining soil data at an appropriate scale for C stocks calculations purposes in Amazonia. There

  2. Vegetation ecology meets ecosystem science: Permanent grasslands as a functional biogeography case study.

    Violle, Cyrille; Choler, Philippe; Borgy, Benjamin; Garnier, Eric; Amiaud, Bernard; Debarros, Guilhem; Diquelou, Sylvain; Gachet, Sophie; Jolivet, Claudy; Kattge, Jens; Lavorel, Sandra; Lemauviel-Lavenant, Servane; Loranger, Jessy; Mikolajczak, Alexis; Munoz, François; Olivier, Jean; Viovy, Nicolas

    2015-11-15

    The effect of biodiversity on ecosystem functioning has been widely acknowledged, and the importance of the functional roles of species, as well as their diversity, in the control of ecosystem processes has been emphasised recently. However, bridging biodiversity and ecosystem science to address issues at a biogeographic scale is still in its infancy. Bridging this gap is the primary goal of the emerging field of functional biogeography. While the rise of Big Data has catalysed functional biogeography studies in recent years, comprehensive evidence remains scarce. Here, we present the rationale and the first results of a country-wide initiative focused on the C3 permanent grasslands. We aimed to collate, integrate and process large databases of vegetation relevés, plant traits and environmental layers to provide a country-wide assessment of ecosystem properties and services which can be used to improve regional models of climate and land use changes. We outline the theoretical background, data availability, and ecoinformatics challenges associated with the approach and its feasibility. We provide a case study of upscaling of leaf dry matter content averaged at ecosystem level and country-wide predictions of forage digestibility. Our framework sets milestones for further hypothesis testing in functional biogeography and earth system modelling.

  3. An approach for detecting five typical vegetation types on the Chinese Loess Plateau using Landsat TM data.

    Wang, Zhi-Jie; Jiao, Ju-Ying; Lei, Bo; Su, Yuan

    2015-09-01

    Remote sensing can provide large-scale spatial data for the detection of vegetation types. In this study, two shortwave infrared spectral bands (TM5 and TM7) and one visible spectral band (TM3) of Landsat 5 TM data were used to detect five typical vegetation types (communities dominated by Bothriochloa ischaemum, Artemisia gmelinii, Hippophae rhamnoides, Robinia pseudoacacia, and Quercus liaotungensis) using 270 field survey data in the Yanhe watershed on the Loess Plateau. The relationships between 200 field data points and their corresponding radiance reflectance were analyzed, and the equation termed the vegetation type index (VTI) was generated. The VTI values of five vegetation types were calculated, and the accuracy was tested using the remaining 70 field data points. The applicability of VTI was also tested by the distribution of vegetation type of two small watersheds in the Yanhe watershed and field sample data collected from other regions (Ziwuling Region, Huangling County, and Luochuan County) on the Loess Plateau. The results showed that the VTI can effectively detect the five vegetation types with an average accuracy exceeding 80 % and a representativeness above 85 %. As a new approach for monitoring vegetation types using remote sensing at a larger regional scale, VTI can play an important role in the assessment of vegetation restoration and in the investigation of the spatial distribution and community diversity of vegetation on the Loess Plateau.

  4. A quantitative assessment of the vegetation types on the island of St. Eustatius, Dutch Caribbean

    Tinde van Andel

    2016-07-01

    Full Text Available Caribbean dry forests are among the most endangered tropical ecosystems on earth. Several studies exist on their floristic composition and their recovery after natural or man-made disturbances, but little is known on the small Dutch Caribbean islands. In this study, we present quantitative data on plant species richness and abundance on St. Eustatius, one of the smallest islands of the Lesser Antilles. We collected and identified trees, shrubs, lianas and herbs in 11 plots of 25 x 25 m in different vegetation types. We compared their floristic composition and structure to vegetation surveys from roughly the same locations in the 1990s and 1950s. We found substantial differences among our 11 plots: vegetation types varied from evergreen forests to deciduous shrubland and open woodland. The number of tree species ≥10 cm DBH ranged between one and 17, and their density between three and 82 per plot. In spite that all plots were subject to grazing by free roaming cattle, canopy height and floristic diversity have increased in the last decades. Invasive species are present in the open vegetation types, but not under (partly closed canopy. Comparison with the earlier surveys showed that the decline of agriculture and conservation efforts resulted in the regeneration of dry forests between the 1950s and 2015. This process has also been reported from nearby islands and offers good opportunities for the future conservation of Caribbean dry forests.

  5. [CHARACTERISTICS OF COMBINED ANESTHESIA WITH EPIDURAL COMPONENTE DEPENDING ON VEGETATIVE NERVOUS SYSTEM TYPE].

    Hasanov, F J; Aslanov, A A; Muradov, N F; Namazova, K N

    2016-01-01

    The research objective was to study the characteristics of combined anesthesia with epidural componente (CAEC) depending on vegetative nervous system type (VNS) in patients who underwent large scale traumatic surgical operations on abdominal cavity organs. The scientific research was conducted in Anaesthesiology--Reanimation Department of the Scientific Surgical Centre named after acad. MA. Topchubashev, the Ministry of Health of the Azerbaijan Republic. The research objects were 69 patients who underwent operations in conditions of CAEC due to different serious surgical pathologies of abdominal cavity organs. VNS type was identified based on electroencephalogram, Cerdo Vegetative Index (CVI), Hildebrandt coefficient (HC) and single neurophysiological tests. The patients were divided into three groups depending on VNS type: I--normotonics--17 patients (24.7%), II--sympathatonics--25 patients (36.2%), and III--vagotonics--27 patients (39.1%). Blood adrenocorticotropic hormone (ACTH) and cortisol concentration were studied in 3 stages: I -preoperative, II--operation traumatic stage, III--the 1st postoperative days. The other indicators (heart rate, systolic blood pressure--SBP, dyastolic blood pressure--DBR average blood pressure--BP ave., pulse oximetry SpO₂, ECG, gases in blood and acid-base balance, electrolytes, blood glucose level, myocardium oxygen demand--MOD) were registered after 20 minutes and the 2nd day after operation besides the above stages. The research results indicated that it is possible to define the vegetative nervous system type superiority based on complex of single tests data, EEG, ECG, Cerdo Vegetative Index, Hildebrandt coefficient. CAEC can be considered optimun alternative of general anesthesia ensuring neurohumoral and hemodynamic stability in large scale, traumatic operations on abdominal cavity organs. Clinical course of CAEC is characterized by firmer hemodynamic and humoral stability in patients with functional balance of

  6. Impact of climate and vegetation type on evapotranspiration from green roofs

    Sia, M. E.; Robinson, C. E.; O'Carroll, D. M.; Voogt, J. A.; Smart, C. C.; Way, D. A.

    2015-12-01

    Green roofs are an increasingly popular low impact development tool used to mitigate the adverse effects of urbanization and the loss of vegetated spaces. The benefits of green roofs include reducing stormwater volume and peak flows, reducing building energy loads, and mitigating the urban heat island effect. Evapotranspiration (ET) is a key process fundamental to hydrologic and thermal performance of green roofs. For example, ET governs the water storage volume available in the soil medium and thus the ability of the green roof to retain and attenuate stormwater. Green roof design considerations such as soil medium depth and plant type impact ET rates. Additionally, climate has a strong impact on ET rates. To date, the influence between climate and green roof design factors (e.g. vegetation type and soil medium depth) on ET rates have not been well quantified. We performed a field study to evaluate the impact of climate, vegetation type, and soil medium depth on ET rates from extensive modular green roofs over prolonged drying periods. Three Canadian cities with distinct climates were chosen as field sites: London, ON, Calgary, AB, and Halifax, NS. At each site, daily module weights were recorded from May to August in 2013 and 2014 for approximately 40 green roof modules. These modules were divided into four vegetation treatments (three single species and one mixed species), and each treatment was divided into two groups of soil medium depth (10 cm or 15 cm). Daily ET rates and seasonal moisture loss were calculated and compared for the modules to determine which treatment provided the highest ET rates. The root depth profile, leaf area index, and stomatal resistance were also measured. On average, daily ET rates among the vegetation treatments did not vary greatly, however, observations on plant survival indicate which plant types are best suited for each site. In all three sites, mixed species in 15 cm of soil medium had higher seasonal moisture loss compared to

  7. Use of High Resolution UAS Imagery to Classify Sub-Arctic Vegetation Types

    Herrick, C.; Palace, M. W.; Finnell, D. R.; Garnello, A.; Sullivan, F.; Anderson, S. M.; Varner, R. K.

    2014-12-01

    Sub-arctic permafrost regions are now experiencing annual warming with a resulting thaw that induces changes to the vegetative landscape. This warming trend is directly correlated to increases in annual greenhouse gas emissions including methane (CH4). Vegetation species and composition are indirect indicators of CH4 flux, and may serve as a proxy for estimating changes in CH4emission over time. Three WorldView-2 images (2m2 spatial resolution, 8 multispectral bands) were acquired in Jul/Aug of 2012-2014 over the Abisko region in northern Sweden. Color infrared (CIR) sub-meter imagery was also collected over a 4km2 area in 2014 using both a multi-rotor helicopter and a fixed wing unmanned aircraft system (UAS). Fifty 1m2 ground sample plots were established; these plots cover 5 major ground cover vegetation classes and were used in classification efforts. Texture analysis was conducted on both UAS and WV-2 imagery. Both an unsupervised k-means clustering algorithm to predict vegetation classes and a supervised classification using both random forests and neural networks were conducted; similar texture analysis and clustering were also performed on the UAS imagery. Classifications of the two imagery types were compared with promising results, thus supporting the use of UAS and high resolution satellite image collection to provide landscape level characterization of vegetation.

  8. Vegetable but not fruit consumption reduces the risk of type 2 diabetes in Chinese women.

    Villegas, Raquel; Shu, Xiao Ou; Gao, Yu-Tang; Yang, Gong; Elasy, Tom; Li, Honglan; Zheng, Wei

    2008-03-01

    We examined associations between fruit and vegetable intake and the incidence of type 2 diabetes (T2D) in a population-based prospective study of 64,191 women with no history of T2D or other chronic diseases at study recruitment and with valid dietary information. Dietary intake was assessed by in-person interviews using a validated FFQ. During 297,755 person-years of follow-up, 1608 new cases of T2D were documented. We used a Cox regression model to evaluate the association of fruit and vegetable intake (g/d) with the risk of T2D. Quintiles of vegetable intake and T2D were inversely associated. The relative risk for T2D for the upper quintile relative to the lower quintile of vegetable intake was 0.72 (95%CI: 0.61-0.85; P Fruit intake was not associated with the incidence of diabetes in this population. Our data suggest that vegetable consumption may protect against the development of T2D.

  9. Ecological and Geochemical Assessment of Woody Vegetation in Tungsten-Molybdenum Mining Area (Buryat Republic, Russia)

    Kasimov, N. S.; Kosheleva, N. E.; Timofeev, I. V.

    2016-08-01

    Biogeochemical studies performed in the impact zone of the Dzhida tungsten- molybdenum mining and processing enterprise in Zakamensk (Buryat Republic, Russia) in 2013 showed that the needles and bark of Lárix sibírica Ledeb. and the leaves and bark of Bétula platyphýlla Sukacs are characterized by certain changes in their trace element (TE) composition. The total index of the biogeochemical transformation Z v which sums all the positive and negative deviations of TE contents from the background values for larch and birch in the city averaged 95 and 46 for their assimilating organs and 30 and 25 for their perennial organs, respectively. This was caused by the increased uptake of W, Mo, V, Pb, Bi, Cd, and Co in the city. The close correlation between TE concentrations in soils and plants was observed for the elements of the strong and moderate biological capturing, including cationic Cu, Zn, Sr, Cd, and Ba and anions of the ore elements W and Mo and the associated Bi. The most intensive TE accumulation was found in the larch needles due to the wax layer which firmly fixes the dust enriched with TEs. Indication of the ecological state of urban woody plants revealed that their organs contain the increased concentrations of Pb and Fe and suffer from the Mn deficiency, which attests to disturbance of photosynthetic processes, most pronounced in the residential area. Birch leaves are characterized by a very low Cu/Zn ratio which detects the imbalance of these elements participating in the synthesis of enzymes.

  10. Browsing preference and ecological carrying capacity of sambar deer (Cervus unicolor brookei) on secondary vegetation in forest plantation.

    Ismail, Dahlan; Jiwan, Dawend

    2015-02-01

    The browsing preference and ecological carrying capacity (ECC) of sambar deer (Cervus unicolor brookei) in acacia plantations for management and conservation of the ecosystem were investigated at Sabal Forest Reserve in Sarawak, Malaysia. The identification of the species browsed by the sambar deer was based on an observation of the plant parts consumed. ECC estimation was based on body weight (BW) and the physiological stages of animals browsed in six fenced 4-ha paddocks. Sambar deer were found foraging on only 29 out of 42 species of secondary vegetation in the acacia plantation. The remaining species are too high for the deer to reach. Planted species, Shorea macrophylla are not palatable to the deer. This augurs well for the integration of sambar deer into shorea plantations. The most frequently exploited plants were Ficus spp. Sambar deer preferred woody species more than non-woody species and they are browser animals. By producing metabolizable energy of 19,000 to 27,000 MJ/ha, the ECC was five head/ha to 5.25 head/ha. Given its contribution to the conservation of wildlife and its capacity to sustain the ecosystem, the sambar deer integrated farming system offers a promising strategy for the future of tropical forestry management.

  11. Assessing climate refugia from a terrestrial vegetation vulnerability assessment for 29 types in California.

    Thorne, J. H.; Bjorkman, J.; Boynton, R.; Stewart, J.; Holguin, A.; Schwartz, M.; Albright, W.

    2015-12-01

    We assessed the climate vulnerability of 29 terrestrial macrogroup vegetation types in the National Vegetation Classification Scheme covering 99% of California. Using a 2015 landcover map, we defined current and future climate exposure of each type by assessing conditions at all known locations. This approach identifies both areas of expected high stress and of climate refugia. Species distribution models of the vegetation types proved to over-predict the extent of occupied lands, compared to their mapped extents. Trait based components of the vulnerability assessment were far less influential on level of vulnerability than climate projection. Various cutoffs can be selected to describe refugia. Here we classed refugia as the 20% of climate conditions most frequently occupied by a type. Under CNRM CM5 RCP 4.5, of 70,143 km2 that are the most climate-insulated locations, 46,420 km2 move to higher levels of climate exposure. At the other extreme of climate projections tested, MIROC ESM RCP 8.5, 59,137 km2 are lost. Four macrogroups lose their refugia under CNRM 4.5: Pacific Northwest Conifer Forests, Mountain Riparian Scrub and Wet Meadow, Salt Marsh, and Great Basin Upland Scrub. Under MIROC 8.5 and additional 8 macrogroups lose the most commonly experienced climate: Subalpine Aspen Forests & Pine Woodlands, Non-Native Forest and Woodlands, North Coast Deciduous Scrub and Terrace Prairie, Coastal Dune and Bluff Scrub, Freshwater Marsh, Wet Mountain Meadow, Big Sagebrush Scrub, and Alpine Vegetation. These results raise interesting questions regarding the definition of refugia. We review the results and ask how appropriate they are for different ecosystem types.

  12. Effects of neighboring vascular plants on the abundance of bryophytes in different vegetation types

    Jägerbrand, Annika K.; Kudo, Gaku; Alatalo, Juha M.; Molau, Ulf

    2012-07-01

    Due to the climate change, vegetation of tundra ecosystems is predicted to shift toward shrub and tree dominance, and this change may influence bryophytes. To estimate how changes in growing environment and the dominance of vascular plants influence bryophyte abundance, we compared the relationship of occurrence of bryophytes among other plant types in a five-year experiment of warming (T), fertilization (F) and T + F in two vegetation types, heath and meadow, in a subarctic-alpine ecosystem. We compared individual leaf area among shrub species to confirm that deciduous shrubs might cause severe shading effect. Effects of neighboring functional types on the performance of Hylocomium splendens was also analyzed. Results show that F and T + F treatments significantly influenced bryophyte abundance negatively. Under natural conditions, bryophytes in the heath site were negatively related to the abundance of shrubs and lichens and the relationship between lichens and bryophytes strengthened after the experimental period. After five years of experimental treatments in the meadow, a positive abundance relationship emerged between bryophytes and deciduous shrubs, evergreen shrubs and forbs. This relationship was not found in the heath site. Our study therefore shows that the abundance relationships between bryophytes and plants in two vegetation types within the same area can be different. Deciduous shrubs had larger leaf area than evergreen shrubs but did not show any shading effect on H. splendens.

  13. Effect of vegetative filter strips on herbicide runoff under various types of rainfall.

    Otto, Stefan; Cardinali, Alessandra; Marotta, Ester; Paradisi, Cristina; Zanin, Giuseppe

    2012-06-01

    Narrow vegetative filter strips proved to effectively reduce herbicide runoff from cultivated fields mainly due to the ability of vegetation to delay surface runoff, promote infiltration and adsorb herbicides. A field trial was conducted from 2007 to 2009 in north-east Italy in order to evaluate the effectiveness of various types of vegetative filter strips to reduce spring-summer runoff of the herbicides mesotrione, metolachlor and terbuthylazine, widely used in maize, and to evaluate the effect of the rainfall characteristics on the runoff volume and concentration. Results show that without vegetative filter strip the herbicide load that reaches the surface water is about 5-6 g ha(-1)year(-1) for metolachlor and terbuthylazine (i.e. 0.5-0.9% of the applied rate), confirming that runoff from flat fields as in the Po Valley can have a minor effect on the water quality, and that most of the risk is posed by a few, or even just one extreme rainfall event with a return period of about 25-27 years, causing runoff with a maximum concentration of 64-77 μg L(-1). Mesotrione instead showed rapid soil disappearance and was observed at a concentration of 1.0-3.8 μg L(-1) only after one extreme (artificial) rainfall. Vegetative filter strips of any type are generally effective and can reduce herbicide runoff by 80-88%. Their effectiveness is steady even under severe rainfall conditions, and this supports their implementation in an environmental regulatory scheme at a catchment or regional scale.

  14. Effect of non-crop vegetation types on conservation biological control of pests in olive groves.

    Paredes, Daniel; Cayuela, Luis; Gurr, Geoff M; Campos, Mercedes

    2013-01-01

    Conservation biological control (CBC) is an environmentally sound potential alternative to the use of chemical insecticides. It involves modifications of the environment to promote natural enemy activity on pests. Despite many CBC studies increasing abundance of natural enemies, there are far fewer demonstrations of reduced pest density and very little work has been conducted in olive crops. In this study we investigated the effects of four forms of non-crop vegetation on the abundance of two important pests: the olive psyllid (Euphyllura olivina) and the olive moth (Prays oleae). Areas of herbaceous vegetation and areas of woody vegetation near olive crops, and smaller patches of woody vegetation within olive groves, decreased pest abundance in the crop. Inter-row ground covers that are known to increase the abundance of some predators and parasitoids had no effect on the pests, possibly as a result of lack of synchrony between pests and natural enemies, lack of specificity or intra-guild predation. This study identifies examples of the right types of diversity for use in conservation biological control in olive production systems.

  15. Effect of non-crop vegetation types on conservation biological control of pests in olive groves

    Daniel Paredes

    2013-07-01

    Full Text Available Conservation biological control (CBC is an environmentally sound potential alternative to the use of chemical insecticides. It involves modifications of the environment to promote natural enemy activity on pests. Despite many CBC studies increasing abundance of natural enemies, there are far fewer demonstrations of reduced pest density and very little work has been conducted in olive crops. In this study we investigated the effects of four forms of non-crop vegetation on the abundance of two important pests: the olive psyllid (Euphyllura olivina and the olive moth (Prays oleae. Areas of herbaceous vegetation and areas of woody vegetation near olive crops, and smaller patches of woody vegetation within olive groves, decreased pest abundance in the crop. Inter-row ground covers that are known to increase the abundance of some predators and parasitoids had no effect on the pests, possibly as a result of lack of synchrony between pests and natural enemies, lack of specificity or intra-guild predation. This study identifies examples of the right types of diversity for use in conservation biological control in olive production systems.

  16. Palaeodistribution modelling of European vegetation types at the Last Glacial Maximum using modern analogues from Siberia: Prospects and limitations

    Janská, Veronika; Jiménez-Alfaro, Borja; Chytrý, Milan; Divíšek, Jan; Anenkhonov, Oleg; Korolyuk, Andrey; Lashchinskyi, Nikolai; Culek, Martin

    2017-03-01

    We modelled the European distribution of vegetation types at the Last Glacial Maximum (LGM) using present-day data from Siberia, a region hypothesized to be a modern analogue of European glacial climate. Distribution models were calibrated with current climate using 6274 vegetation-plot records surveyed in Siberia. Out of 22 initially used vegetation types, good or moderately good models in terms of statistical validation and expert-based evaluation were computed for 18 types, which were then projected to European climate at the LGM. The resulting distributions were generally consistent with reconstructions based on pollen records and dynamic vegetation models. Spatial predictions were most reliable for steppe, forest-steppe, taiga, tundra, fens and bogs in eastern and central Europe, which had LGM climate more similar to present-day Siberia. The models for western and southern Europe, regions with a lower degree of climatic analogy, were only reliable for mires and steppe vegetation, respectively. Modelling LGM vegetation types for the wetter and warmer regions of Europe would therefore require gathering calibration data from outside Siberia. Our approach adds value to the reconstruction of vegetation at the LGM, which is limited by scarcity of pollen and macrofossil data, suggesting where specific habitats could have occurred. Despite the uncertainties of climatic extrapolations and the difficulty of validating the projections for vegetation types, the integration of palaeodistribution modelling with other approaches has a great potential for improving our understanding of biodiversity patterns during the LGM.

  17. Vegetation type modifies the cycling and aromaticity of DOC and N in small-scale urban stormwater basins

    Nocco, M. A.; Dolliver, H.; Balster, N. J.

    2012-12-01

    Urban land use can cause ecological degradation of surface waters through stormwater inputs of dissolved organic carbon (DOC) and total dissolved nitrogen (TDN). Green infrastructure practices such as small-scale (m2) vegetated stormwater basins (e.g. bioretention basins, rain gardens, bioswales) have been implemented for the past 20 years to reduce stormwater quantity and improve water quality in urban ecosystems. Although the efficacy of these practices rests on an ecological assumption that plant-soil interactions will alter the C and N cycles relative to surrounding urban infrastructure, the impact of vegetation type on the biogeochemistry of urban stormwater basins is not well understood. We hypothesized that the two most prevalent types of vegetation planted in stormwater basins in the Midwestern United States, native prairie and woody shrubs, differ in their cycling and export of C and N due to differences in relative woody and parenchymatic tissue inputs to soil organic matter, root morphology, and root exudation. We tested this hypothesis in an open-air field laboratory consisting of 9 vegetated mesocosms (3 native prairie, 3 woody shrub, 3 bare soil) designed in 2005 according to WI-DNR specifications for residential stormwater basin construction. During precipitation events in July-October 2011, we collected stormwater runoff from an adjacent tin roof (417 m2) and conducted 9 runoff applications that mimicked the rate and intensity of runoff that would be received by a small-scale (5.9 m2) stormwater basin in the urban environment during a 2.54 cm rain event. We instrumented each mesocosm to quantify (1) first flush and peak flow concentration of DOC and TDN during gravitational soil water flux (2) DOC and TDN concentration in soil pore space after gravitational water flux ceased, and (3) SUVA254 as an optical proxy for aromaticity in the first flush and peak flow of gravitational soil water flux. Results show significant differences (psoil. The DOC

  18. 蔬菜地农药施用的土壤生态风险评估%Soil Ecological Risk Assessment of Pesticides in Vegetable Fields

    邓勋飞; 詹宇; 王祥云; 吕晓男

    2014-01-01

    Residues of pesticides are often detected in soil, surface water, and groundwater in intensive agricultural areas. Exposure to pes-ticides may have potential impacts on human health and ecosystem safety. To mitigate the negative impacts of pesticide residues, growers, policy makers, and researchers seek tools to quantitatively assess potential risks of pesticides. In this study, an assessment model for ecologi-cal risk of pesticides in soils was developed based on temperature, interception fraction of vegetables, and application rates and properties of active ingredients in interested pesticides. Geo-statistical analysis was then employed to determine the basic spatial units of ecological risk assessment for vegetable production. Finally quantitative risk assessment of pesticide uses in vegetable soils was conducted using a total of 130 pesticide use records for 2010 collected together with soil and climate parameters in vegetable fields of reclamation areas in Xiaoshan, Zhejiang Province. A total of 20 pesticides with predicted ecological risks was identified. Of which, carbendazim, used for asparagus crop in April, had the highest ecological risk, and its short-term and long-term risk values were up to 104.6 and 106.1, respectively. Imidacloprid, chlorpyrifos, acetamiprid, and azoxystrobin were the next, all showing high ecological risks in soil(risk values >85). Emamectin benzoate, iprodione, and fipronil did not show ecological risk(risk values <60). For each vegetable parcellwith multi pesticides applied, an integrated ecological risk value(IERV)of different pesticides was also calculated, and a visualized map for spatial distribution of IERV for vegetable parcels was achieved. A case study of IERV in April showed that higher risks were present in several parcels planted with asparagus, while lower risks in radish fields. In summary, this approach would be useful for growers and pesticide control advisors in screening high risk areas and mitigating the impacts

  19. The influence of distinct types of aquatic vegetation on the flow field

    Valyrakis, Manousos; Barcroft, Stephen; Yagci, Oral

    2014-05-01

    The Sustainable management of fluvial systems dealing with flood prevention, erosion protection and restoration of rivers and estuaries requires implementation of soft/green-engineering methods. In-stream aquatic vegetation can be regarded as one of these as it plays an important role for both river ecology (function) and geomorphology (form). The goal of this research is to offer insight gained from pilot experimental studies on the effects of a number of different elements modeling instream, aquatic vegetation on the local flow field. It is hypothesized that elements of the same effective "blockage" area but of distinct characteristics (structure, porosity and flexibility), will affect both the mean and fluctuating levels of the turbulent flow to a different degree. The above hypothesis is investigated through a set of rigorous set of experimental runs which are appropriately designed to assess the variability between the interaction of aquatic elements and flow, both quantitatively and qualitatively. In this investigation three elements are employed to model aquatic vegetation, namely a rigid cylinder, a porous but rigid structure and a flexible live plant (Cupressus Macrocarpa). Firstly, the flow field downstream each of the mentioned elements was measured under steady uniform flow conditions employing acoustic Doppler velocimetry. Three-dimensional flow velocities downstream the vegetation element are acquired along a measurement grid extending about five-fold the element's diameter. These measurements are analyzed to develop mean velocity and turbulent intensity profiles for all velocity components. A detailed comparison between the obtained results is demonstrative of the validity of the above hypothesis as each of the employed elements affects in a different manner and degree the flow field. Then a flow visualization technique, during which fluorescent dye is injected upstream of the element and images are captured for further analysis and comparison, was

  20. Behavioural types and ecological effects in a natural population of the cooperative cichlid Neolamprologus pulcher

    Witsenburg, Fardo; Schuerch, Roger; Otti, Oliver; Heg, Dik

    2010-01-01

    The ecological relevance of behavioural syndromes is little studied in cooperative breeding systems where it is assumed that the behavioural type might influence individual decisions on helping and dispersal (e.g. shy, nonaggressive and nonexplorative individuals remain philopatric and helpful, wher

  1. Satellite monitoring of different vegetation types by differential optical absorption spectroscopy (DOAS in the red spectral range

    T. Wagner

    2007-01-01

    Full Text Available A new method for the satellite remote sensing of different types of vegetation and ocean colour is presented. In contrast to existing algorithms relying on the strong change of the reflectivity in the red and near infrared spectral region, our method analyses weak narrow-band (few nm reflectance structures (i.e. "fingerprint" structures of vegetation in the red spectral range. It is based on differential optical absorption spectroscopy (DOAS, which is usually applied for the analysis of atmospheric trace gas absorptions. Since the spectra of atmospheric absorption and vegetation reflectance are simultaneously included in the analysis, the effects of atmospheric absorptions are automatically corrected (in contrast to other algorithms. The inclusion of the vegetation spectra also significantly improves the results of the trace gas retrieval. The global maps of the results illustrate the seasonal cycles of different vegetation types. In addition to the vegetation distribution on land, they also show patterns of biological activity in the oceans. Our results indicate that improved sets of vegetation spectra might lead to more accurate and more specific identification of vegetation type in the future.

  2. Differences between Used and Available Microhabitats and Vegetation Types for Giant Gartersnakes Associated with a Restored Marsh in California

    U.S. Geological Survey, Department of the Interior — These data describe differences in percent cover of microhabitats and vegetation types at giant gartersnake locations and random points paired with giant gartersnake...

  3. Accuracy assessment of airphoto interpretation of vegetation types and disturance levels on winter seismic trails, Arctic National Wildlife Refuge, Alaska

    US Fish and Wildlife Service, Department of the Interior — An accuracy assessment was conducted to evaluate the photo-interpretation of vegetation types and disturbance levels along seismic trails in the Arctic National...

  4. Projected Impacts of 21st Century Climate Change on Potential Habitat for Vegetation and Forest Types in Russia

    Soja, A. J.; Tchebakova, N. M.; Parfenova, E. I.; Cantin, A.; Conard, S. G.

    2015-12-01

    Global GCMs have demonstrated profound potential for projections to affect the distribution of terrestrial ecosystems and individual species at all hierarchical levels. We modeled progression of potential Russian ecotones and forest-forming species as the climate changes. Large-scale bioclimatic models were developed to predict Russian zonal vegetation (RuBCliM) and forest types (ForCliM) from three bioclimatic indices (1) growing degree-days above 5 degrees C; (2) negative degree-days below 0 C ; and (3) an annual moisture index (ratio of growing degree days to annual precipitation). The presence or absence of continuous permafrost was explicitly included in the models as limiting the forests and tree species distribution. All simulations to predict vegetation change across Russia were run by coupling our bioclimatic models with bioclimatic indices and the permafrost distribution for the baseline period and for the future 2020, 2050 and 2100 simulated by 3 GCMs (CGCM3.1, HadCM3 and IPSLCM4) and 3 climate change scenarios (A1B, A2 and B1). Under these climate scenarios, it is projected the zonobiomes will shift far northward to reach equilibrium with the change in climate. Under the warmer and drier projected future climate, about half of Russia would be suitable for the forest-steppe ecotone and grasslands, rather than for forests. Water stress tolerant light-needled taiga would have an increased advantage over water-loving dark-needled taiga. Permafrost-tolerant L. dahurica taiga would remain the dominant forest across permafrost. Increases in severe fire weather would lead to increases in large, high-severity fires, especially at boundaries between forest ecotones, which can be expected to facilitate a more rapid progression of vegetation towards a new equilibrium with the climate. Adaptation to climate change may be facilitated by: assisting migration of forests by seed transfers to establish genotypes that may be more ecologically suited as climate changes

  5. Major Vegetation Types of the Soutpansberg Conservancy and the Blouberg Nature Reserve, South Africa

    Theo H.C. Mostert

    2008-05-01

    Full Text Available The Major Megetation Types (MVT and plant communities of the Soutpansberg Centre of Endemism are described in detail, with special reference to the Soutpansberg Conservancy and the Blouberg Nature Reserve. Phytosociological data from 442 sample plots were ordinated using a DEtrended CORrespondence ANAlysis (DECORANA and classified using TWo-Way INdicator SPecies ANalysis (TWINSPAN. The resulting classification was further refined with table-sorting procedures based on the Braun–Blanquet floristic–sociological approach of vegetation classification using MEGATAB. Eight MVT’s were identified and described as Eragrostis lehmanniana var. lehmanniana–Sclerocarya birrea subsp. caffra Blouberg Northern Plains Bushveld, Euclea divinorum–Acacia tortilis Blouberg Southern Plains Bushveld, Englerophytum magalismontanum–Combretum molle Blouberg Mountain Bushveld, Adansonia digitata–Acacia nigrescens Soutpansberg Arid Northern Bushveld, Catha edulis–Flueggia virosa Soutpansberg Moist Mountain Thickets, Diplorhynchus condylocarpon–Burkea africana Soutpansberg Leached Sandveld, Rhus rigida var. rigida–Rhus magalismontanum subsp. coddii Soutpansberg Mistbelt Vegetation and Xymalos monospora–Rhus chirendensis Soutpansberg Forest Vegetation.

  6. Abundance and Dynamics of Soil Labile Carbon Pools Under Different Types of Forest Vegetation

    JIANG Pei-Kun; XU Qiu-Fang

    2006-01-01

    Soil organic matter (SOM) in forest ecosystems is not only important to global carbon (C) storage but also to sustainable management of forestland with vegetation types, being a critical factor in controlling the quantity and dynamics of SOM. In this field experiment soil plots with three replicates were selected from three forest vegetation types: broadleaf,Masson pine (Pinus massoniana Lamb.), and Chinese fir (Cunninghamia lanceolata Hook.). Soil total organic C (TOC),two easily oxidizable C levels (EOC1 and EOC2, which were oxidized by 66.7 mmol L-1 K2Cr2O7 at 130-140 ℃ and333 mmol L-1 KMnO4 at 25 ℃, respectively), microbial biomass C (MBC), and water-soluble organic C (WSOC)were analyzed for soil samples. Soil under the broadleaf forest stored significantly higher TOC (P ≤ 0.05). Because of its significantly larger total soil C storage, the soil under the broadleaf forest usually had significantly higher levels (P ≤ 0.05)of the different labile organic carbons, EOC1, EOC2, MBC, and WSOC; but when calculated as a percentage of TOC each labile C fraction of the broadleaf forest was significantly lower (P ≤ 0.05) than one of the other two forests. Under all the three vegetation types temperature as well as quality and season of litter input generally affected the dynamics of different organic C fractions in soils, with EOC1, EOC2, and MBC increasing closely following increase in temperature,whereas WSOC showed an opposite trend.

  7. Using vegetation cover type to predict and scale peatland methane dynamics.

    McArthur, K. J.; McCalley, C. K.; Palace, M. W.; Varner, R. K.; Herrick, C.; DelGreco, J. L.

    2015-12-01

    Permafrost ecosystems contain about 50% of the global soil carbon. As these northern ecosystems experience warmer temperature, permafrost thaws and may result in an increase in atmospheric methane. We examined a thawing and discontinuous permafrost boundary at Stordalen Mire, in Northern Sweden, in an effort to better understand methane emissions. Stable isotope analysis of methane in peatland porewater can give insights into the pathway of methane production. By measuring δ13CH4 we can predict whether a system is dominated by either hydrogenotrophic or acetaclastic methane production. Currently, it is a challenge to scale these isotopic patterns, thus, atmospheric inversion models simply assume that acetoclastic production dominates. We analyzed porewater samples collected across a range of vegetation cover types for δ13CH4 using a QCL (Quantum Cascade Laser Spectrometer) in conjunction with highly accurate GPS (3-10cm) measurements and high-resolution UAV imaging. We found δ13CH4 values ranging from -88‰ to -41‰, with averages based on cover type and other vegetation features showing differences of up to -15‰. We then used a computer neural network to predict cover types across Stordalen Mire from UAV imagery based on field-based plot measurements and training samples.. This prediction map was used to scale methane flux and isotope measurements. Our results suggest that the current values used in atmospheric inversion studies may oversimplify the relationship between plant and microbial communities in complex permafrost landscapes. As we gain a deeper understanding of how vegetation relates to methanogenic communities, understanding the spatial component of ecosystem methane metabolism and distribution will be increasingly valuable.

  8. Types of fruits and vegetables used in commercial baby foods and their contribution to sugar content.

    Garcia, Ada Lizbeth; McLean, Kimberley; Wright, Charlotte M

    2016-10-01

    Fruits and vegetables (F&V) are often featured in names of commercial baby foods (CBFs). We aimed to survey all available CBFs in the UK market with F&V included in the food name in order to describe the amount and types of F&V used in CBF and their contribution to total sugar content. Food labels were used to identify F&V and total sugar content. Fruits were more common than vegetables in names of the 329 CBFs identified. The six most common F&V in the names were all relatively sweet: apple, banana, tomato, mango, carrot and sweet potato. The percentage of F&V in the foods ranged from a median of 94% for sweet-spoonable to 13% for dry-savoury products. Fruit content of sweet foods (n = 177) was higher than vegetable content of savoury foods (n = 152) with a median (IQR) of 64.0 g/100 g (33.0-100.0) vs. 46.0 g/100 g (33-56.7). Fruit juice was added to 18% of products. The proportion of F&V in CBF correlated significantly with sugar content for all the food types except dry-savoury food (sweet-spoonable r = 0.24, P = 0.006; savoury-spoonable r = 0.65, P < 0.001; sweet-dry r = 0.81, P < 0.001; savoury-dry r = 0.51, P = 0.06) and explained up to two-thirds of the variation in sugar content. The F&V content of CBFs mainly consists of fruits and relatively sweet vegetables which are unlikely to encourage preferences for bitter-tasting vegetables or other non-sweet foods. F&V contribute significantly to the total sugar content, particularly of savoury foods.

  9. Invertebrate availability and vegetation characteristics explain use of nonnesting cover types by mature-forest songbirds during the postfledging period

    Streby, Henry M.; Peterson, Sean M.; Andersen, D.E.

    2011-01-01

    Some species of mature-forest-nesting songbirds use regenerating clearcuts and forested wetlands during the postfledging period (between nesting and migration). Relatively dense vegetation structure and abundant food resources in non-mature-forest cover types have been hypothesized to explain this phenomenon. We examined the relative importance of vegetation structure and invertebrate availability on use of nonnesting cover types by adult and hatch-year Ovenbirds (Seiurus aurocapilla) and American Redstarts (Setophaga ruticilla) during the postfledging period of 2009 in northern Minnesota. We used mist nets to sample bird use of forested wetlands and regenerating clearcuts of three age groups: 1-6, 7-12, and 16-19 yr after harvest. We modeled captures of birds using vegetation characteristics and invertebrate availability sampled around nets as explanatory variables. For all birds studied, captures were best explained by food availability and secondarily by vegetation characteristics including litter depth and woody debris for Ovenbirds and canopy height for American Redstarts. Shrub-level invertebrate availability received a cumulative weight of 0.74-0.99 in Akaike's information criterion corrected ranked models for adult and hatch-year birds of both species. Vegetation density and variation in vegetation density explained almost no variation in captures of either species. We conclude that both invertebrate availability and some vegetation characteristics influence use of nonnesting cover types by Ovenbirds and American Redstarts during the postfledging period, but that invertebrate availability is generally the stronger predictor of that use. ?? 2011 Association of Field Ornithologists.

  10. Variations of deep soil moisture under different vegetation types and influencing factors in a watershed of the Loess Plateau, China

    Fang, Xuening; Zhao, Wenwu; Wang, Lixin; Feng, Qiang; Ding, Jingyi; Liu, Yuanxin; Zhang, Xiao

    2016-08-01

    Soil moisture in deep soil layers is a relatively stable water resource for vegetation growth in the semi-arid Loess Plateau of China. Characterizing the variations in deep soil moisture and its influencing factors at a moderate watershed scale is important to ensure the sustainability of vegetation restoration efforts. In this study, we focus on analyzing the variations and factors that influence the deep soil moisture (DSM) in 80-500 cm soil layers based on a soil moisture survey of the Ansai watershed in Yan'an in Shanxi Province. Our results can be divided into four main findings. (1) At the watershed scale, higher variations in the DSM occurred at 120-140 and 480-500 cm in the vertical direction. At the comparable depths, the variation in the DSM under native vegetation was much lower than that in human-managed vegetation and introduced vegetation. (2) The DSM in native vegetation and human-managed vegetation was significantly higher than that in introduced vegetation, and different degrees of soil desiccation occurred under all the introduced vegetation types. Caragana korshinskii and black locust caused the most serious desiccation. (3) Taking the DSM conditions of native vegetation as a reference, the DSM in this watershed could be divided into three layers: (i) a rainfall transpiration layer (80-220 cm); (ii) a transition layer (220-400 cm); and (iii) a stable layer (400-500 cm). (4) The factors influencing DSM at the watershed scale varied with vegetation types. The main local controls of the DSM variations were the soil particle composition and mean annual rainfall; human agricultural management measures can alter the soil bulk density, which contributes to higher DSM in farmland and apple orchards. The plant growth conditions, planting density, and litter water holding capacity of introduced vegetation showed significant relationships with the DSM. The results of this study are of practical significance for vegetation restoration strategies, especially

  11. Effects of Vegetable Oil Type and Lipophilic Emulsifiers on the Induction Period of Fat Crystallization.

    Miyagawa, Yayoi; Ogawa, Takenobu; Nakagawa, Kyuya; Adachi, Shuji

    2015-01-01

    The induction period of crystallization, which is defined as the time required for oil to start to crystallize, is useful indicator of the freeze-thaw stability of food emulsions such as mayonnaise. We investigated the induction period of vegetable oils with low melting points, such as rapeseed and soybean oils, which are commonly employed for mayonnaise production. The induction period was measured by monitoring the temperature of a specimen during storage at low temperature. The induction period depended on the type of oil and lipophilic emulsifier, emulsifier concentration, and storage temperature. The effect of the oil type on the induction period depended on the composition of the oil. Differential scanning calorimetry (DSC) analyses of the lipophilic emulsifiers suggested that the melting trend of the emulsifier is strongly related to the induction period.

  12. On the potential vegetation feedbacks that enhance phosphorus availability – insights from a process-based model linking geological and ecological timescales

    C. Buendía

    2014-07-01

    We find that active P uptake is an essential mechanism for sustaining P availability on long timescales, whereas biotic de-occlusion might serve as a buffer on timescales shorter than 10 000 yr. Although active P uptake is essential for reducing P losses by leaching, humid lowland soils reach P limitation after around 100 000 yr of soil evolution. Given the generalized modelling framework, our model results compare reasonably with observed or independently estimated patterns and ranges of P concentrations in soils and vegetation. Furthermore, our simulations suggest that P limitation might be an important driver of biomass production efficiency (the fraction of the gross primary productivity used for biomass growth, and that vegetation on old soils has a smaller biomass production rate when P becomes limiting. With this study, we provide a theoretical basis for investigating the responses of terrestrial ecosystems to P availability linking geological and ecological timescales under different environmental settings.

  13. Distinguishing Bark Beetle-infested Vegetation by Tree Species Types and Stress Levels using Landsat Data

    Sivanpillai, R.; Ewers, B. E.; Speckman, H. N.; Miller, S. N.

    2015-12-01

    In the Western United States, more than 3 million hectares of lodgepole pine forests have been impacted by the Mountain pine beetle outbreak, while another 166,000 hectares of spruce-fir forests have been attacked by Spruce beetle. Following the beetle attack, the trees lose their hydraulic conductivity thus altering their carbon and water fluxes. These trees go through various stages of stress until mortality, described by color changes in their needles prior to losing them. Modeling the impact of these vegetation types require thematically precise land cover data that distinguishes lodgepole pine and spruce-fir forests along with the stage of impact since the ecosystem fluxes are different for these two systems. However, the national and regional-scale land cover datasets derived from remotely sensed data do not have this required thematic precision. We evaluated the feasibility of multispectral data collected by Landsat 8 to distinguish lodgepole pine and spruce fir, and subsequently model the different stages of attack using field data collected in Medicine Bow National Forest (Wyoming, USA). Operational Land Imager, onboard Landsat 8 has more spectral bands and higher radiometric resolution (12 bit) in comparison to sensors onboard earlier Landsat missions which could improve the ability to distinguish these vegetation types and their stress conditions. In addition to these characteristics, its repeat coverage, rigorous radiometric calibration, wide swath width, and no-cost data provide unique advantages to Landsat data for mapping large geographic areas. Initial results from this study highlight the importance of SWIR bands for distinguishing different levels of stress, and the need for ancillary data for distinguishing species types. Insights gained from this study could lead to the generation of land cover maps with higher thematic precision, and improve the ability to model various ecosystem processes as a result of these infestations.

  14. Vegetation types alter soil respiration and its temperature sensitivity at the field scale in an estuary wetland.

    Guangxuan Han

    Full Text Available Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively. During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m(-2 s(-1, followed by the Suaeda salsa site (0.77 µmol CO2 m(-2 s(-1 and the bare soil site (0.41 µmol CO2 m(-2 s(-1. The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland.

  15. Suitability of the vegetation types in Mexico's Tamaulipas state for the siting of hazardous waste treatment plants.

    Cram, Silke; Sommer, Irene; Morales, Luis-Miguel; Oropeza, Oralia; Carmona, Estela; González-Medrano, Francisco

    2006-07-01

    A land suitability study was carried out by applying a multiple-criteria technique to 12 different vegetation types in Mexico's Tamaulipas state to help select potentially suitable sites for hazardous waste treatment plants. Species richness, spatial distribution, and uniqueness were selected as the criteria for estimating a vegetation type's suitability. Using the analytical hierarchy process, we ranked and mapped vegetation types, then compared the results with rankings of the same vegetation types based only on their number of endemic species. The suitabilities of the various vegetation types were ordered in more or less the same way by both methods, except in two cases for which the results were very different. The method proved to be a useful tool despite the availability of only partial (mostly qualitative) information; under such circumstances, expert experience can be incorporated in the evaluation process to a limited degree. The technique described in this paper has a high potential to aid decisions when many opinions and options must be considered simultaneously.

  16. Fuel Consumption and Fire Emissions Estimates in Siberia: Impact of Vegetation Types, Meteorological Conditions, Forestry Practices and Fire Regimes

    Kukavskaya, Elena; Conard, Susan; Ivanova, Galina; Buryak, Ludmila; Soja, Amber; Zhila, Sergey

    2015-04-01

    Boreal forests play a crucial role in carbon budgets with Siberian carbon fluxes and pools making a major contribution to the regional and global carbon cycle. Wildfire is the main ecological disturbance in Siberia that leads to changes in forest species composition and structure and in carbon storage, as well as direct emissions of greenhouse gases and aerosols to the atmosphere. At present, the global scientific community is highly interested in quantitative and accurate estimates of fire emissions. Little research on wildland fuel consumption and carbon emission estimates has been carried out in Russia until recently. From 2000 to 2007 we conducted a series of experimental fires of varying fireline intensity in light-coniferous forest of central Siberia to obtain quantitative and qualitative data on fire behavior and carbon emissions due to fires of known behavior. From 2009 to 2013 we examined a number of burned logged areas to assess the potential impact of forest practices on fire emissions. In 2013-2014 burned areas in dark-coniferous and deciduous forests were examined to determine fuel consumption and carbon emissions. We have combined and analyzed the scarce data available in the literature with data obtained in the course of our long-term research to determine the impact of various factors on fuel consumption and to develop models of carbon emissions for different ecosystems of Siberia. Carbon emissions varied drastically (from 0.5 to 40.9 tC/ha) as a function of vegetation type, weather conditions, anthropogenic effects and fire behavior characteristics and periodicity. Our study provides a basis for better understanding of the feedbacks between wildland fire emissions and changing anthropogenic disturbance patterns and climate. The data obtained could be used by air quality agencies to calculate local emissions and by managers to develop strategies to mitigate negative smoke impacts on the environmentand human health.

  17. Burn Severities, Fire Intensities, and Impacts to Major Vegetation Types from the Cerro Grande Fire

    Balice, Randy G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bennett, Kathryn D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wright, Marjorie A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2004-12-15

    The Cerro Grande Fire resulted in major impacts and changes to the ecosystems that were burned. To partially document these effects, we estimated the acreage of major vegetation types that were burned at selected burn severity levels and fire intensity levels. To accomplish this, we adopted independently developed burn severity and fire intensity maps, in combination with a land cover map developed for habitat management purposes, as a basis for the analysis. To provide a measure of confidence in the acreage estimates, the accuracies of these maps were also assessed. In addition, two other maps of comparable quality were assessed for accuracy: one that was developed for mapping fuel risk and a second map that resulted from a preliminary application of an evolutionary computation software system, called GENIE.

  18. Impacts of grassland types and vegetation cover changes on surface air temperature in the regions of temperate grassland of China

    Shen, Xiangjin; Liu, Binhui; Li, Guangdi; Yu, Pujia; Zhou, Daowei

    2016-10-01

    The sensitivity of surface air temperature response to different grassland types and vegetation cover changes in the regions of temperate grassland of China was analyzed by observation minus reanalysis (OMR) method. The basis of the OMR approach is that reanalysis data are insensitive to local surface properties, so the temperature differences between surface observations and reanalysis can be attributed to land effects. Results showed that growing-season air temperature increased by 0.592 °C/decade in the regions of temperate grassland of China, with about 31 % of observed warming associated with the effects of grassland types and vegetation cover changes. For different grassland types, the growing-season OMR trend was the strongest for temperate desert steppe (0.259 °C/decade) and the weakest for temperate meadow (0.114 °C/decade). Our results suggest that the stronger intraseasonal changes of grassland vegetation are present, the more sensitive the OMR trend responds to the intraseasonal vegetation cover changes. In August and September, the OMR of temperate meadow showed a weak cooling trend. For temperate meadow, about 72.2 and 72.6 % of surface cooling were explained by both grassland type and increase of vegetation cover for August and September, respectively. For temperate steppe and temperate desert steppe, due to the limited soil moisture and little evaporative cooling feedback, the vegetation changes have no significant effect on the surface air temperature. These results indicate that the impact of grassland types and vegetation cover changes should be considered when projecting further climate change in the temperate grassland region of China.

  19. 植被指数-地面温度特征空间的生态学内涵及其应用%Ecological Connotation and Application of the Vegetation Index-Surface Temperature Feature Space

    江东; 王乃斌; 杨小唤; 刘红辉

    2001-01-01

    植被指数与地面温度是描述土地覆盖特征的重要参数,对两种数据的综合分析,可以衍生出更丰富、更清晰的地表信息,有助于更加准确、有效地认知土地覆盖/土地利用的时空变化规律.本文探讨了植被指数与地面温度构成的二维向量空间的物理意义与生态学内涵,以基于NOAA AVHRR的时间序列数据为本底,分析了不同土地覆盖类型在该特征空间上的时序变化规律,并以黄淮海地区主要农作物冬小麦为例,研究了植被指数-地面温度指标与干旱、半干旱地区农作物产量之间的响应关系.%Studies on character and variation of land cover/land use become more and more important in geographical and ecological research. Vegetation index and surface temperature are important parameters to describe characters of land covers. More useful information will be created by integrated analyses of these two kinds of data together, which will help us to find out main principles of the temporal and spatial variation of land cover/land use. The paper focused on physical connotation and ecological meaning of the vegetation index-surface temperature feature space, analyzed temporal variation of different type of land covers in this feature space using NOAA AVHRR remote sensing data, and did much site work on relationship between water index and winter wheat yield in the Huang Huaihai campagna. Following views have been set forth and tested based on these data: (1) Large area and long time serials land surface parameters could be retrieved from remote sensed information; (2) Different types of land covers have different characters in the vegetation index-surface temperature feature space; (3) Water index, derived from vegetation index and surface temperature, is turned out to be a good indicate of growing situation of crops.

  20. Natural vegetal regeneration as a basis for the development of strategies for ecological restoration in three Protected Biotopes in the Maya Biosphere Reserve, Guatemala

    Manolo José García Vettorazzi

    2015-07-01

    Full Text Available The natural ecosystems of the Maya Biosphere Reserve contain high levels of biodiversity providing environmental goods and services to society, so their conservation is strategic for local and regional development. However, there is a increasing tendency to disturb these ecosystems as a result of human activities, so is necessary to develop strategies that minimize the negative impacts and allow the recovery of degraded natural ecosystems. Existing information on the functioning of essential ecological processes of local ecosystems is sparse and is scattered, limiting the development of strategies. It was proposed to study the dynamics of natural regeneration of vegetation as a basis for defining strategies of ecological restoration in three Protected Biotopes in Peten and adjacent areas, by characterizing the structure and composition of vegetation in six categories of natural regeneration and forest without recent disturbance. Two modified Whitaker 0.1 ha plots were plotted by category and seed bank samples were collected. With this information a conceptual framework of natural regeneration was developed for application in restoration strategies at local and landscape scales.

  1. Diversification of Nitrogen Sources in Various Tundra Vegetation Types in the High Arctic.

    Skrzypek, Grzegorz; Wojtuń, Bronisław; Richter, Dorota; Jakubas, Dariusz; Wojczulanis-Jakubas, Katarzyna; Samecka-Cymerman, Aleksandra

    2015-01-01

    Low nitrogen availability in the high Arctic represents a major constraint for plant growth, which limits the tundra capacity for carbon retention and determines tundra vegetation types. The limited terrestrial nitrogen (N) pool in the tundra is augmented significantly by nesting seabirds, such as the planktivorous Little Auk (Alle alle). Therefore, N delivered by these birds may significantly influence the N cycling in the tundra locally and the carbon budget more globally. Moreover, should these birds experience substantial negative environmental pressure associated with climate change, this will adversely influence the tundra N-budget. Hence, assessment of bird-originated N-input to the tundra is important for understanding biological cycles in polar regions. This study analyzed the stable nitrogen composition of the three main N-sources in the High Arctic and in numerous plants that access different N-pools in ten tundra vegetation types in an experimental catchment in Hornsund (Svalbard). The percentage of the total tundra N-pool provided by birds, ranged from 0-21% in Patterned-ground tundra to 100% in Ornithocoprophilous tundra. The total N-pool utilized by tundra plants in the studied catchment was built in 36% by birds, 38% by atmospheric deposition, and 26% by atmospheric N2-fixation. The stable nitrogen isotope mixing mass balance, in contrast to direct methods that measure actual deposition, indicates the ratio between the actual N-loads acquired by plants from different N-sources. Our results enhance our understanding of the importance of different N-sources in the Arctic tundra and the used methodological approach can be applied elsewhere.

  2. Ecological aspects of lake regulation in Northern Finland. Part 2. Geomorphology and vegetation of the littoral zone. Ekologiset naekoekohdat joidenkin Pohjois-Suomen jaervien saeaennoestelyssae. Osa 2. Rannan geomorfologia ja vesikasvillisuus

    Hellsten, S.; Alasaarela, E. (9830800FI); Keraenen, R.; Nykaenen, M. (Oulu Univ. (Finland)); Neuvonen, I. (Kainuun Vesi- ja ympaeristoepiiri, Kajaani (Finland))

    1989-02-01

    Ecological aspects of lake regulation were studied in certain lakes in northern Finland in 1984-1987. The general aims of the project were to analyze the effects of regulation on lake ecosystems and to produce information that can be applied when assessing the possible effects of hydroelectric projects. The effects of lake regulation were easy to observe in the littoral zone of Lake Ontojaervi, the sandy shores in particular were unstable both above and below the water level. The shores were very much steeper than those of Lake Lentua, which affected the distribution of bottom types, minerogenic bottoms were more common than in the latter lake. The results from the two lakes were used to calculate a simple model to forecast the distribution of bottom types of Lake Ontojaervi before regulation. The effect of penetration by ice was also easy to recognize on the shores of Lake Ontojaervi; the surface sediment being frozen to a greater depth than in Lake Lentua. Beneath the freezing zone in ice just pressed down on the sediment. The littoral vegetation decreased markedly after regulation and was entirely absent in open places. Changes in abundance were particularly clear, with decreases in the large isoetides and helophytes and increases of small isoetides. The results from Lake Lentua were used to formulate a simple ecological model for the frequency of macrophytes.

  3. Assessing onset and length of greening period in six vegetation types in Oaxaca, Mexico, using NDVI-precipitation relationships.

    Gómez-Mendoza, L; Galicia, L; Cuevas-Fernández, M L; Magaña, V; Gómez, G; Palacio-Prieto, J L

    2008-07-01

    Variations in the normalized vegetation index (NDVI) for the state of Oaxaca, in southern Mexico, were analyzed in terms of precipitation anomalies for the period 1997-2003. Using 10-day averages in NDVI data, obtained from AVHRR satellite information, the response of six types of vegetation to intra-annual and inter-annual fluctuations in precipitation were examined. The onset and temporal evolution of the greening period were studied in terms of precipitation variations through spectral analysis (coherence and phase). The results indicate that extremely dry periods, such as those observed in 1997 and 2001, resulted in low values of NDVI for much of Oaxaca, while good precipitation periods produced a rapid response (20-30 days of delay) from a stressed to a non-stressed condition in most vegetation types. One of these rapid changes occurred during the transition from dry to wet conditions during the summer of 1998. As in many parts of the tropics and subtropics, the NDVI reflects low frequency variations in precipitation on several spatial scales. Even after long dry periods (2001-2002), the various regional vegetation types are capable of recovering when a good rainy season takes place, indicating that vegetation types such as the evergreen forests in the high parts of Oaxaca respond better to rainfall characteristics (timing, amount) than to temperature changes, as is the case in most mid-latitudes. This finding may be relevant to prepare climate change scenarios for forests, where increases in surface temperature and precipitation anomalies are expected.

  4. Ecosystem CO2 production during winter in a Swedish subarctic region: the relative importance of climate and vegetation type

    Grogan, Paul; Jonasson, Sven Evert

    2006-01-01

    in these predictions, we know relatively little about the plot and landscape-level controls on tundra biogeochemical cycling in wintertime as compared to summertime. We investigated the relative influence of vegetation type and climate on CO2 production rates and total wintertime CO2 release in the Scandinavian...... in northern Sweden. Both climate and vegetation type were strong interactive controls on ecosystem CO2 production rates during winter. Of all variables tested, soil temperature explained by far the largest amount of variation in respiration rates (41-75%). Our results indicate that vegetation type only...... will respond to climate change during winter because they indicate a threshold (~1 m) above which there would be little effect of increased snow accumulation on wintertime biogeochemical cycling....

  5. Temperature and substrate controls on intra-annual variation in ecosystem respiration in two subarctic vegetation types

    Grogan, Paul; Jonasson, Sven Evert

    2005-01-01

    tundra vegetation types in northern Sweden through a full annual cycle. We used a plant biomass removal treatment to differentiate bulk soil organic matter respiration from total ecosystem respiration in each vegetation type. Plant-associated and bulk soil organic matter carbon pools each contributed...... the sensitivity of ecosystem respiration to intra-annual variations in soil temperature for both vegetation types, indicating that respiration derived from recent plant carbon fixation was more temperature sensitive than respiration from bulk soil organic matter carbon stores. Accurate assessment of the potential......Arctic ecosystems are important in the context of climate change because they are expected to undergo the most rapid temperature increases, and could provide a globally significant release of CO2 to the atmosphere from their extensive bulk soil organic carbon reserves. Understanding the relative...

  6. Discussion on Vegetation Succession in Restoration Ecology Field%恢复生态学领域的植被演替研究综述

    郭帅; 赵宏霞

    2011-01-01

    For the restoration of degraded ecosystems,the essence is community succession,the first and foremost task is to choose the right build group of plant species,the ultimate aim is to establish a healthy and stable plant community,the challenge is to understand and use the vegetation succession theory to accelerate the restoration process.Vegetation succession theory is the fundamental theory to guide the restoration and reconstruction of degraded ecosystem.The development,the important status and the practice application in ecological restoration,and the research methods and trends were reviewed in this article in order to inspire new ideas of vegetation succession in restoration ecology.%退化生态系统恢复的实质是群落演替,首要任务是选择合适的建群植物种类,最终目的是建立健康稳定的植物群落,所面临的挑战是理解和利用植被演替理论来完成并加速恢复进程.植被演替理论是指导退化生态系统恢复与重建的重要基础理论.本文对植被演替理论的发展、在生态恢复中的重要地位和实践应用、植被演替的研究方法及趋势进行了综述,旨在启发恢复生态学领域植被演替研究的新思路.

  7. 河道植被驳岸筛选及其生态效应分析%Selection and Ecological Effect Analysis of Vegetation Riverbanks

    范洁群; 宋祥甫; 邹国燕; 付子轼; 吴淑杭; 潘琦

    2011-01-01

    为了筛选出护坡效果良好,且具有较好生态效益的河道植被,在模拟农村驳岸上种植马蹄金、美人蕉、杞柳3种植被,对其坡面界面伴生植物、节肢动物、土壤微生物的种群多样性和稳定性等进行生态效应研究.结果表明:除秋季伴生植物外,春秋2季3种植物的生物量,伴生植物和节肢动物的Shannon-Weiner指数和均匀度指数均为:马蹄金<美人蕉<杞柳;Simpson多样性指数:马蹄金>美人蕉>杞柳.且杞柳土壤微生物的细菌总数最多,达到7.7× 108 cfu/g土,硝化菌和反硝化菌达到3.2× 106 cfu/g土以上.秋季马蹄金被加拿大一枝黄花等伴生植物所取代.可见,杞柳驳岸是生态效应最佳的植被驳岸,其次是美人蕉驳岸,而马蹄金驳岸不适合作植被驳岸.%In order to select out the effective riverbanks vegetation, ecological effect analysis of diversity and stability which of accompanying plants, arthropoda, soil microbe had been studied on the three vegetation riverbanks, where Dichonda repens, Canna indica and Salix Integra were planted. The results showed that, despite of accompanying plants in autumn, biomass of plants, Shannon-Weiner index and evenness index of accompanying plants and arthropoda of 3 vegetation riverbanks were Dichonda repens Canna indica~> Salix integra. Bacteria amount in Salix integra soil was most, which was 7.7×l08cfu/g soil, nitrifier and denitrifying bacterium were more than 3.2×106 cfu/g soil. In autumn, Solidgo canadensis and other accompanying plants replaced Dichonda repens. At all, Salix integra riverbank was the best vegetation riverbank according to ecological effect, following with Canna indica and Dichonda repens was unsuitable for riverbank vegetation.

  8. Pool-type fishways: two different morpho-ecological cyprinid species facing plunging and streaming flows.

    Branco, Paulo; Santos, José M; Katopodis, Christos; Pinheiro, António; Ferreira, Maria T

    2013-01-01

    Fish are particularly sensitive to connectivity loss as their ability to reach spawning grounds is seriously affected. The most common way to circumvent a barrier to longitudinal connectivity, and to mitigate its impacts, is to implement a fish passage device. However, these structures are often non-effective for species with different morphological and ecological characteristics so there is a need to determine optimum dimensioning values and hydraulic parameters. The aim of this work is to study the behaviour and performance of two species with different ecological characteristics (Iberian barbel Luciobarbus bocagei-bottom oriented, and Iberian chub Squalius pyrenaicus-water column) in a full-scale experimental pool-type fishway that offers two different flow regimes-plunging and streaming. Results showed that both species passed through the surface notch more readily during streaming flow than during plunging flow. The surface oriented species used the surface notch more readily in streaming flow, and both species were more successful in moving upstream in streaming flow than in plunging flow. Streaming flow enhances upstream movement of both species, and seems the most suitable for fishways in river systems where a wide range of fish morpho-ecological traits are found.

  9. Effects of Vegetation Type and Management Practice on Soil Respiration of Grassland in Northern Japan

    Minaco Adachi

    2013-01-01

    Full Text Available Soil respiration rate in two types of grassland dominated with Zoysia japonica and Miscanthus sinensis, respectively, and under two management practices (undisturbed and intentionally burned for the M. sinensis grassland was investigated for understanding the effects of grassland vegetation type and management practices on the relationship between soil temperature and soil respiration in northern Japan. Soil temperatures at depth of 1 cm in the Z. japonica (ZJ and burned M. sinensis (MSb plots had a larger temporal variation than that in the control M. sinensis (MSc plot prior to early July. However, the coefficient of temperature sensitivity ( values, based on soil respiration rates and soil temperatures at 5 cm depth in the ZJ and MSb plots, were 1.3 and 2.9. These rates were lower than that in the MSc plot (4.3, meaning that soil respiration showed lower activity to an increase in soil temperature in the ZJ and MSb plots. In addition, monthly carbon fluxes from soil in these plots were smaller than that in the MSc plot. These results suggested that artificial disturbance would decrease soil microbial or/and plant root respiration, and it would contribute to the plant productivity. Future studies should examine the effects of the intensity and period of management on the soil respiration rate.

  10. Ecological Impacts of the Cerro Grande Fire: Predicting Elk Movement and Distribution Patterns in Response to Vegetative Recovery through Simulation Modeling October 2005

    Rupp, Susan P. [Texas Tech Univ., Lubbock, TX (United States)

    2005-10-01

    In May 2000, the Cerro Grande Fire burned approximately 17,200 ha in north-central New Mexico as the result of an escaped prescribed burn initiated by Bandelier National Monument. The interaction of large-scale fires, vegetation, and elk is an important management issue, but few studies have addressed the ecological implications of vegetative succession and landscape heterogeneity on ungulate populations following large-scale disturbance events. Primary objectives of this research were to identify elk movement pathways on local and landscape scales, to determine environmental factors that influence elk movement, and to evaluate movement and distribution patterns in relation to spatial and temporal aspects of the Cerro Grande Fire. Data collection and assimilation reflect the collaborative efforts of National Park Service, U.S. Forest Service, and Department of Energy (Los Alamos National Laboratory) personnel. Geographic positioning system (GPS) collars were used to track 54 elk over a period of 3+ years and locational data were incorporated into a multi-layered geographic information system (GIS) for analysis. Preliminary tests of GPS collar accuracy indicated a strong effect of 2D fixes on position acquisition rates (PARs) depending on time of day and season of year. Slope, aspect, elevation, and land cover type affected dilution of precision (DOP) values for both 2D and 3D fixes, although significant relationships varied from positive to negative making it difficult to delineate the mechanism behind significant responses. Two-dimensional fixes accounted for 34% of all successfully acquired locations and may affect results in which those data were used. Overall position acquisition rate was 93.3% and mean DOP values were consistently in the range of 4.0 to 6.0 leading to the conclusion collar accuracy was acceptable for modeling purposes. SAVANNA, a spatially explicit, process-oriented ecosystem model, was used to simulate successional dynamics. Inputs to the

  11. Ecology of E. coli O157:H7 and Salmonella enterica in the primary vegetable production chain

    Franz, E.; Bruggen, van A.H.C.

    2008-01-01

    There is an increased concern that plants might be more important as a carrier for human enteric pathogens like E. coli O157:H7 and Salmonella enterica serovars than previously thought. This review summarizes the knowledge available on the ecology of E. coli O157:H7 and Salmonella enterica in the pr

  12. Spatial Heterogeneity of Vegetation in China

    2007-01-01

    The spatial heterogeneity and ecological characteristics of 74 vegetation types and the lack of vegetation type within the 9.6 million km2 of Chinese territory were studied using data from the China vegetation map. The analysis used 877 large quadrats 10 mm×10 mm (actual size 100 km×100 km), which covered about 8.77 million km2. Each large-quadrat was divided into four small 5 mm×5 mm quadrats (actual size 50 km×50 km). The frequency of occurrence of all vegetation types was recorded in each small quadrat.The survey using the Shiyomi method of vegetation analysis based on the beta-binomial distribution was adopted to describe the frequency of occurrence and spatial heterogeneity for each kind of vegetation. The weighted average heterogeneity of all the vegetation types in the landscape provides a measure of the landscape level heterogeneity which describes the spatial intricacy of the existing vegetation composition.The maximum spatial vegetation heterogeneity was 0.8620 in the frigid-temperate coniferous forest of Larix(V1), which dominates cold moist northeast China. The minimum spatial heterogeneity with a low occurrence was the Caragana tibetica in the gravel desert in the western Yellow River Hetao area. The minimum occurrence with a low spatial heterogeneity was the Monsoon rainforest on rock in Guangxi and Yunnan Provinces. The vegetation types on the Qing-Zang Plateau were found to be representative of Chinese vegetation because of the very high occurrence and spatial heterogeneity of these vegetation types. The weighted average of the heterogeneity was 0.677, while the vegetation diversity index was 3.29.

  13. Seasonal variations in the biomass, quantity and quality of agar, from the reproductive and vegetative stages of Gracilaria (verrucosa type)

    Whyte, J.N.C.; Englar, J.R.; Saunders, R.G.; Lindsay, J.C.

    1981-09-01

    Optimum growth of Gracilaria (verrucosa type) in British Columbia occurred between 5 and 6 meters below mean field level and correlated with solar radiation throughout the season. Vegetative populations declined with a consequent increase in reproductive forms to a maximum in July. Tetrasporophytes dominated the reproductive population and in July attained the greatest seasonal biomass of all forms of the alga. Maximum population and biomass were attained by carposporophytes in July and by male gametophytes one month earlier. An inverse relationship between biomass and yield of agar was apparent only for the vegetative and tetrasporic forms of the alga. Variations in yields, gel strengths, and gelation characteristics of the agars isolated, were demonstrated to be dependent on time of season and life stages of the alga. Ranked in the following decreasing order of merit as a source of agar were the cystocarpic, tetrasporic, vegetative and male gametophytic forms of Gracilaria (verrucosa type).

  14. TYPE OF VEGETATION AND DISTRIBUTION IN XUNHUA COUNTY%循化县植被类型及分布

    袁青杉

    2012-01-01

    The data of remote sense T M image have been used to type of vegetation of Xunhua county , the re- suits showed that there were 5 types of vegetation forest, shrub , grassland, desert and meadow and 20 vegeta- tion groups, It was obvious vegetation perpendicularity distribution.%根据遥感影像TM数据信息及其文献资料,结合野外验证研究循化县植被类型及其分布。结果表明循化县共有森林、灌丛、草原、荒漠、草甸5个植被型组,20个植被群系;并且植被垂直分布明显。

  15. Effects of different vegetation types on the shear strength of root-permeated soils

    Yildiz, Anil; Graf, Frank; Rickli, Christian; Springman, Sarah M.

    2016-04-01

    The effects of vegetation and, in particular, of forests on the stability of slopes are well recognized and have been widely studied in recent decades. However, there is still a lack of understanding of the underlying processes that occur prior to triggering superficial failures in root-permeated soil. Thus, appropriate quantification of the vegetation effects on the shear strength of soil is crucial in order to be able to evaluate the stability of a vegetated slope. Direct shear testing is widely employed to determine the shearing response of root-permeated soil. However, mechanical aspects of direct shear apparatuses may affect the shear strength parameters derived, which often remains unnoticed and hampers direct comparison between different studies. A robust Inclinable Large-scale Direct Shear Apparatus (ILDSA), with dimensions of 500x500x400 mm, was built in order to shear root-permeated soil specimens and to analyse the influence of the machine setup on the results, too. Two different sets of planted specimens were prepared using moraine (SP-SM) from a recent landslide area in Central Switzerland: a first set consisting of Alnus incana, Trifolium pratense, Poa pratensis and a second set, consisting of these three species complemented with Salix appendiculata, Achillea millefolium, Anthyllis vulneraria. Direct shear tests were conducted on specimens planted with the different vegetation types, at a constant rate of horizontal displacement of 1 mm/min up to a maximum horizontal displacement of 190 mm, and under three different applied normal stresses: 6 kPa, 11 kPa and 16 kPa. Artificial rainfall was applied at a constant intensity (100 mm/h) prior to shearing. Tensiometers had been installed close to the shear surface and were monitored continuously to obtain the matric suction during the saturation process. Suctions were reduced as close to 0 kPa as possible, in order to simulate the loss of strength after a heavy period of rainfall. The analyses of the above

  16. Assessment of the transfer of {sup 137}Cs in three types of vegetables consumed in Hong Kong

    Yu, K.N.; Mao, S.Y.; Young, E.C.M

    1998-12-01

    A dynamic food chain model has been built for the modeling of the transfer of {sup 137}Cs in three types of vegetables consumed in Hong Kong, namely, white flowering cabbage (Brassica chinensis), head lettuce (Lactuca sativa) and celery (Apium graveolens). Some parameters have been estimated from the experimental data obtained in this work. The experimental data include the transfer factors of {sup 137}Cs from soil to the different vegetable species which are determined through high resolution gamma spectrometry, maximum crop biomasses for the vegetable species, the dry-to-fresh ratios for the vegetable species, the bulk density of soil layers and the average concentration of {sup 137}Cs in air. The derived parameters include the deposition rate and the root uptake rate, information for tillage, the logistic growth model and radionuclide concentrations in vegetables. The dynamic food chain model is solved by the Birchall-James algorithm to give the {sup 137}Cs concentration in subsurface soil, from the 0.1-25 cm soil layer, and the {sup 137}Cs concentration in harvested and unwashed vegetables. As validation of the model and parameters, the concentrations obtained experimentally and from the model are compared and are found to be in good agreement.

  17. Effect of Replacing Pork Fat with Vegetable Oils on Quality Properties of Emulsion-type Pork Sausages.

    Lee, Hyun-Jin; Jung, Eun-Hee; Lee, Sang-Hwa; Kim, Jong-Hee; Lee, Jae-Joon; Choi, Yang-Ii

    2015-01-01

    This study was conducted to evaluate the quality properties of emulsion-type pork sausages when pork fat is replaced with vegetable oil mixtures during processing. Pork sausages were processed under six treatment conditions: T1 (20% pork fat), T2 (10% pork fat + 2% grape seed oil + 4% olive oil + 4% canola oil), T3 (4% grape seed oil + 16% canola oil), T4 (4% grape seed oil + 4% olive oil + 12% canola oil), T5 (4% grape seed oil + 8% olive oil + 8% canola oil), and T6 (4% grape seed oil + 12% olive oil + 4% canola oil). Proximate analysis showed significant (pfat content among the emulsion-type pork sausages. Furthermore, replacement with vegetable oil mixtures significantly decreased the ash content (psausages. Also, cholesterol content in T6 was significantly lower than T2 (psausages were significantly (preplacement. On the contrary, cohesiveness and springiness in the T4 group were similar to those of group T1. The unsaturated fatty acid content in emulsion-type pork sausages was increased by vegetable oil mixtures replacement. Replacement of pork fat with mixed vegetable oils had no negative effects on the quality properties of emulsion-type pork sausages, and due to its reduced saturated fatty acid composition, the product had the quality characteristics of the healthy meat products desired by consumers.

  18. Sebkhas as ecological archives and the vegetation and landscape history of southeastern Tunisia during the last two millennia

    Schulz, E.; Abichou, A.; Hachicha, T.; Pomel, S.; Salzmann, U.; Zouari, K.

    2002-05-01

    Sebkhas are temporary lacustrine systems depending on the number and extension of floodings. They may create laminated sediments which can be exploited as ecological archives. Contrary to those of meromictic lakes they are seasonal but not annual. After each flooding a detritus layer and a plasmo-condensed layer of bacteria and algae are formed in the water body or film and during the subsequent dessication a third subaeric layer of evaporites is build up. These laminae show a quasi-textile fabric and they can trap and conserve any dust and fine grained material. A high resolution pollendiagram covering the last two millennia as well as geochemical analysis from a southeastern Tunisian sebkha demonstrate the potentials of these ecological archives.

  19. Regular, high, and moderate intake of vegetables rich in antioxidants may reduce cataract risk in Central African type 2 diabetics

    Mvitu M

    2012-06-01

    Full Text Available Moise Mvitu,1 Benjamin Longo-Mbenza,2 Dieudonné Tulomba,3 Augustin Nge31Department of Ophthalmology, University of Kinshasa, Democratic Republic of Congo; 2Faculty of Health Sciences, Walter Sisulu University, South Africa; 3Biostatistics Unit, Lomo Medical Center and Heart of Africa Center of Cardiology, Kinshasa, Democratic Republic of CongoBackground: Antioxidant nutrients found in popularly consumed vegetables, including red beans, are thought to prevent diabetic complications. In this study, we assessed the frequency and contributing factors of intake of fruits and vegetables rich in antioxidants, and we determined their impact on the prevention of diabetes-related cataract extraction.Methods: This was a cross-sectional study, run in Congo among 244 people with type 2 diabetes mellitus. An intake of ≥three servings of vegetables rich in antioxidants/day, intake of red beans, consumption of fruit, and cataract extraction were considered as dependent variables.Results: No patient reported a fruit intake. Intake of red beans was reported by 64 patients (26.2%, while 77 patients (31.6% reported ≥three servings of vegetables rich in antioxidants. High socioeconomic status (OR = 2.3; 95% CI: 1.1–12.5; P = 0.030 and moderate alcohol intake (OR = 4; 95% CI: 1.1–17.4; P = 0.049 were the independent determinants of eating ≥three servings of vegetables rich in antioxidants. Red beans intake (OR = 0.282; 95% CI: 0.115–0.687; P > 0.01 and eating ≥three servings of vegetables rich in antioxidants (OR = 0.256; 95% CI: 0.097–0.671; P = 0.006 were identified as independent and protective factors against the presence of cataracts (9.8% n = 24, whereas type 2 diabetes mellitus duration ≥3 years was the independent risk factor for cataract extraction (OR = 6.3; 95% CI: 2.1–19.2; P > 0.001 in the model with red beans intake and OR = 7.1; 95% CI: 2.3–22.2; P > 0.001 in the model with ≥three servings of vegetables rich in antioxidants

  20. Soil microbial communities are shaped by vegetation type and park age in cities under cold climate.

    Hui, Nan; Jumpponen, Ari; Francini, Gaia; Kotze, D Johan; Liu, Xinxin; Romantschuk, Martin; Strömmer, Rauni; Setälä, Heikki

    2017-03-01

    Soil microbes play a key role in controlling ecosystem functions and providing ecosystem services. Yet, microbial communities in urban green space soils remain poorly characterized. Here we compared soil microbial communities in 41 urban parks of (i) divergent plant functional types (evergreen trees, deciduous trees and lawn) and (ii) different ages (constructed 10, ∼50 and >100 years ago). These microbial communities were also compared to those in 5 control forests in southern Finland. Our results indicate that, despite frequent disturbances in urban parks, urban soil microbes still followed the classic patterns typical of plant-microbe associations in natural environments: both bacterial and fungal communities in urban parks responded to plant functional groups, but fungi were under tighter control of plants than bacteria. We show that park age shaped the composition of microbial communities, possibly because vegetation in old parks have had a longer time to modify soil properties and microbial communities than in young parks. Furthermore, control forests harboured distinct but less diverse soil microbial communities than urban parks that are under continuous anthropogenic disturbance. Our results highlight the importance of maintaining a diverse portfolio of urban green spaces and plant communities therein to facilitate complex microbial communities and functions in urban systems.

  1. Lake Bathymetric Aquatic Vegetation

    Minnesota Department of Natural Resources — Aquatic vegetation represented as polygon features, coded with vegetation type (emergent, submergent, etc.) and field survey date. Polygons were digitized from...

  2. CHARACTERIZATION OF THE TYPE AND EXTENT OF NUTRIENT LIMITATION IN GRASSLAND VEGETATION USING A BIOASSAY WITH INTACT SODS

    OLFF, H; PEGTEL, DM

    1994-01-01

    An important methodological problem in plant ecology concerns the way in which the type and extent of nutrient limitation in terrestrial communities should be assessed. Conclusions on nutrient limitation have been founded mainly on soil extractions, fertiliser trials and tissue nutrient concentratio

  3. Biodiesel classification by base stock type (vegetable oil) using near infrared spectroscopy data

    Balabin, Roman M., E-mail: balabin@org.chem.ethz.ch [Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich (Switzerland); Safieva, Ravilya Z. [Gubkin Russian State University of Oil and Gas, 119991 Moscow (Russian Federation)

    2011-03-18

    The use of biofuels, such as bioethanol or biodiesel, has rapidly increased in the last few years. Near infrared (near-IR, NIR, or NIRS) spectroscopy (>4000 cm{sup -1}) has previously been reported as a cheap and fast alternative for biodiesel quality control when compared with infrared, Raman, or nuclear magnetic resonance (NMR) methods; in addition, NIR can easily be done in real time (on-line). In this proof-of-principle paper, we attempt to find a correlation between the near infrared spectrum of a biodiesel sample and its base stock. This correlation is used to classify fuel samples into 10 groups according to their origin (vegetable oil): sunflower, coconut, palm, soy/soya, cottonseed, castor, Jatropha, etc. Principal component analysis (PCA) is used for outlier detection and dimensionality reduction of the NIR spectral data. Four different multivariate data analysis techniques are used to solve the classification problem, including regularized discriminant analysis (RDA), partial least squares method/projection on latent structures (PLS-DA), K-nearest neighbors (KNN) technique, and support vector machines (SVMs). Classifying biodiesel by feedstock (base stock) type can be successfully solved with modern machine learning techniques and NIR spectroscopy data. KNN and SVM methods were found to be highly effective for biodiesel classification by feedstock oil type. A classification error (E) of less than 5% can be reached using an SVM-based approach. If computational time is an important consideration, the KNN technique (E = 6.2%) can be recommended for practical (industrial) implementation. Comparison with gasoline and motor oil data shows the relative simplicity of this methodology for biodiesel classification.

  4. Factors Affecting Distribution of Vegetation Types on Abandoned Cropland in the Hilly-Gullied Loess Plateau Region of China

    2008-01-01

    A study was conducted in the forest-steppe region of the Loess Plateau to provide insight into the factors affecting the process of vegetation establishment,and to provide recommendations for the selection of indigenous species in order to speed up the succession process and to allow the establishment of vegetation more resistant to soil erosion.Four distinctive vegetation types were identified,and their distribution was affected not only by the time since abandonment but also by other environmental factors,mainly soil water and total P in the upper soil layers.One of the vegetation types,dominated by Artemisia scoparia,formed the early successional stage after abandonment while the other three types formed later successional stages with their distribution determined by the soil water content and total P.It can be concluded that the selection of appropriate species for introduction to accelerate succession should be determined by the local conditions and especially the total P concentration and soil water content.

  5. Satellite observations of high northern latitude vegetation productivity changes between 1982 and 2008: ecological variability and regional differences

    Beck, Pieter S. A.; Goetz, Scott J.

    2011-12-01

    In the first paragraph of the section '2. Data sets and methods', the Normalized Difference Vegetation Index (NDVI) data set used was incorrectly referred to as GIMMS-NDVI version 3G with a 0.084° spatial resolution. This should be corrected to GIMMS-NDVI version G with a 0.07° spatial resolution. Accordingly, the acknowledgement should state 'We would like to thank ... Jim Tucker and Jorge Pinzon for providing the GIMMS version G data', instead of 'We would like to thank ... Jorge Pinzon for providing the GIMMS 3G data'.

  6. Evolution of growth habit, inflorescence architecture, flower size, and fruit type in Rubiaceae: its ecological and evolutionary implications.

    Sylvain G Razafimandimbison

    Full Text Available During angiosperm evolution, innovations in vegetative and reproductive organs have resulted in tremendous morphological diversity, which has played a crucial role in the ecological success of flowering plants. Morindeae (Rubiaceae display considerable diversity in growth form, inflorescence architecture, flower size, and fruit type. Lianescent habit, head inflorescence, small flower, and multiple fruit are the predominant states, but arborescent habit, non-headed inflorescence, large flower, and simple fruit states occur in various genera. This makes Morindeae an ideal model for exploring the evolutionary appearances and transitions between the states of these characters. We reconstructed ancestral states for these four traits using a bayesian approach and combined nuclear/chloroplast data for 61 Morindeae species. The aim was to test three hypotheses: 1 self-supporting habit is generally ancestral in clades comprising both lianescent and arborescent species; 2 changes from lianescent to arborescent habit are uncommon due to "a high degree of specialization and developmental burden"; 3 head inflorescences and multiple fruits in Morindeae evolved from non-headed inflorescences and simple fruits, respectively. Lianescent habit, head inflorescence, large flower, and multiple fruit are inferred for Morindeae, making arborescent habit, non-headed inflorescence, small flower, and simple fruit derived within the tribe. The rate of change from lianescent to arborescent habit is much higher than the reverse change. Therefore, evolutionary changes between lianescent and arborescent forms can be reversible, and their frequency and trends vary between groups. Moreover, these changes are partly attributed to a scarcity of host trees for climbing plants in more open habitats. Changes from large to small flowers might have been driven by shifts to pollinators with progressively shorter proboscis, which are associated with shifts in breeding systems towards

  7. Effects of ecological engineering on water balance under two different vegetation scenarios in the Qilian Mountain, northwestern China

    Fei Tian

    2016-03-01

    New hydrological insights for the region: After the ecological engineering, water yield and soil water content experienced an increment of 32%, and 46%. The opposite trend was monitored in runoff and evapotranspiration, which decreased by 48% and 4%, respectively. Therefore ecosystem restoration have increased soil water retention capacity, a greater proportion of precipitation reaching the catchment is absorbed by the soil rather than flowing out of the region as runoff. Therefore trade-offs between environmental sustainability and water resources security should be carefully addressed in arid region that experienced severe water shortages.

  8. Residues and potential ecological risks of veterinary antibiotics in manures and composts associated with protected vegetable farming.

    Zhang, Haibo; Luo, Yongming; Wu, Longhua; Huang, Yujuan; Christie, Peter

    2015-04-01

    Veterinary antibiotics (VAs) are emerging contaminants and enter into soil principally by agricultural application of organic fertilizer. A total of 33 solid animal manures and 17 compost samples from protected vegetable farms in nine areas of China were analyzed for the antibiotic classes of tetracyclines, fluoroquinolones, sulfonamides, and macrolides (17 substances in total). Oxytetracycline was found as a dominant compound in the samples, and its highest concentration reached 416.8 mg kg(-1) in a chicken manure sample from Shouguang, Shandong Province. Among the samples, animal manures (especially pig manure) contained higher VA residues than composts. However, fluoroquinolones exhibited higher persistence in the compost samples than other antibiotic classes. This is particularly the case in the rice husk compost, which contained the highest level of ofloxacin and ciprofloxacin (1334.5 and 1717.4 μg kg(-1) on average, respectively). The veterinary antibiotic profile in the risk husk compost had a good relationship with that in the corresponding manures. The refined commercial compost had the lowest VA residues among the compost samples in general. This implied that composting process might be important to reduce the antibiotic residue. High residue of antibiotics in soil was assumed to be a hazard to ecosystem. This is especially noticeable under current application rates (150 t ha(-1) a(-1)) in protected vegetable farming because over half of the samples exhibited a risk quotient (RQ) >1 for one or more antibiotics.

  9. VEGETATION TYPE AND THE INTERTIDAL MACROINVERTEBRATE FAUNA OF A BRACKISH MARSH: PHRAGMITES VS. SPARTINA

    The responses of tidal marsh macroinvertebrate assemblages to the conversion of Spartina alterniflora marshes to marshes dominated by the invasive reed, Phragmites australis, are poorly understood. Changes in edaphic, vegetative, hydrological, and detrital conditions that attend ...

  10. Vegetation Cover Types of St. Vincent Island N.W.R.

    US Fish and Wildlife Service, Department of the Interior — The objectives of this vegetative study on St. Vincent National Wildlife Refuge were to: (1) identify and describe the major plant communities and associations on...

  11. Identification of Forest Vegetation Using Vegetation Indices

    Yuan Jinguo; Wang Wei

    2004-01-01

    Spectral feature of forest vegetation with remote sensing techniques is the research topic all over the world, because forest plays an important role in human beings' living environment. Research on vegetation classification with vegetation index is still very little recently. This paper proposes a method of identifying forest types based on vegetation indices,because the contrast of absorbing red waveband with reflecting near-infrared waveband strongly for different vegetation types is recognized as the theoretic basis of vegetation analysis with remote sensing. Vegetation index is highly related to leaf area index, absorbed photosynthetically active radiation and vegetation cover. Vegetation index reflects photosynthesis intensity of plants and manifests different forest types. According to reflectance data of forest canopy and soil line equation NIR=1.506R+0.0076 in Jingyuetan, Changchun of China, many vegetation indices are calculated and analyzed. The result shows that the relationships between vegetation indices and forest types are that perpendicular vegetation index (PVI) identifies broadleaf forest and coniferous forest the most easily;the next is transformed soil-adjusted vegetation index(TSVI) and modified soil-adjusted vegetation index(MSVI), but their calculation is complex. Ratio vegetation index (RVT) values of different coniferous forest vary obviously, so RVI can classify conifers.Therefore, the combination of PVI and RVI is evaluated to classify different vegetation types.

  12. Altering Their Ecological Niche: Investigating the Response of Avian Migrants to Changes in Vegetation Phenology at Northern Latitudes

    Budde, M. E.; Ward, D. H.; Ely, C. R.; Handel, C. M.; Hupp, J. W.

    2009-12-01

    The impacts of global climate change are expected to be most severe at high northern latitudes. There is now strong evidence to support the hypothesis that such changes have had dramatic effects on the phenology of spring vegetative growth in these areas. One aspect of this change that has not been thoroughly investigated is how these changes vary across habitats and whether sub-Arctic and Arctic avifauna have adapted to shifts in plant phenology by modifying the timing of migration and nesting. A recent study showed that certain bird species have experienced population decline due to the varied timing of seasonal events and points to the fact that the degree of risk facing migratory birds is not well quantified. Plant phenology is especially sensitive to annual variation in temperature and precipitation and is a major determinant of plant species distribution, making it a good indicator of climate change effects. Migratory birds are considered one of the most vulnerable groups to the impacts of climate change because climate affects bird movement and distribution through species-specific physiological tolerances and changes in food and habitat resources. In this study we analyze the evidence for long-term plant phenology changes across different biomes of Alaska using satellite remote sensing techniques. We correlate this variability with ground-based measurements of avian migration and breeding. Specifically, we try to determine if the timing of spring green-up is synchronized across breeding areas or whether the process has become fractured across intervening biomes, potentially disrupting the timing of migration and breeding, putting species at risk. Using satellite-based time series of Normalized Difference Vegetation Index (NDVI) data, we create spatially explicit maps of seasonal vegetation metrics and correlate those with the timing and distribution of avian migrant populations. Preliminary investigation focused on the last 10 year period (2000-2009) and

  13. Vegetation Map and Vegetation Monographs of China

    GUO Ke

    2010-01-01

    @@ Vegetation Map of China As the most significant component of an ecosystem,vegetation plays the most important role in maintaining biodiversity and providing the necessary resources for human beings.A vegetation map shows the major vegetation types of a region and their geographic distribution patterns.

  14. Impact of vegetation types on soil organic carbon stocks SOC-S in Mediterranean natural areas

    Parras-Alcántara, Luis; Lozano-García, Beatriz; Cantudo-Pérez, Marta

    2015-04-01

    Soils play a key role in the carbon geochemical cycle because they can either emit large quantities of CO2 or on the contrary they can act as a store for carbon. Agriculture and forestry are the only activities that can achieve this effect through photosynthesis and the carbon incorporation into carbohydrates (Parras-Alcántara et al., 2013). The Mediterranean evergreen oak Woodland (MEOW - dehesa) is a type of pasture with scattered evergreen and deciduous oak stands in which cereals are often grown under the tree cover. It is a system dedicated to the combined production of Iberian swine, sheep, fuel wood, coal and cork as well as to hunting. These semi-natural areas still preserve some of the primitive vegetation of the Mediterranean oak forests. The dehesa is a pasture where the herbaceous layer is comprised of either cultivated cereals such as oat, barley and wheat or native vegetation dominated by annual species, which are used as grazing resources. These Iberian open woodland rangelands (dehesas) have been studied from different points of view: hydrologically, with respect to soil organic matter content, as well as in relation to gully erosion, topographical thresholds, soil erosion and runoff production, soil degradation and management practices…etc, among others. The soil organic carbon stock capacity depends not only on abiotic factors such as the mineralogical composition and the climate, but also on soil use and management (Parras et al., 2014 and 2015). In Spanish soils, climate, use and management strongly affect the carbon variability, mainly in soils in dry Mediterranean climates characterized by low organic carbon content, weak structure and readily degradable soils. Hontoria et al. (2004) emphasized that the climate and soil use are two factors that greatly influence carbon content in the Mediterranean climate. This research sought to analyze the SOC stock (SOCS) variability in MEOW - dehesa with cereals, olive grove and Mediterranean oak forest

  15. Nutritional differences and leaf acclimation of climbing plants and the associated vegetation in different types of an Andean montane rainforest.

    Salzer, J; Matezki, S; Kazda, M

    2006-03-01

    Climbing plants are known to play an important role in tropical forest systems, but key features for their distribution are only partly understood. Investigation was carried out to find if climbers differ from self-supporting vegetation in their adjustment of leaf parameters over a wide variety of light regimes in different forest types along an altitudinal gradient. Relative photon flux density (PFDrel) was assessed above 75 pairs of strictly linked climbers and supporting vegetation on seven plots between 2,020 and 2,700 m a.s.l. along a mountain range in South-Ecuador up to the Páramo vegetation. Leaf samples from both growth forms were analyzed for leaf area (LA), specific leaf mass (LMA), mass and area-based carbon and nitrogen concentration (C, Carea, N, and Narea) and concentrations of P, K, Ca, Mg, Mn and Al. Leaf size of climbers was independent of general light condition, whereas the leaf size of the self-supporting vegetation increased in shade. LMA increased as expected with altitude and irradiance for both growth forms, but climbers generally built smaller leaves with lower LMA. N, P, and K concentrations were higher in the leaves of climbers than in their supporters. Relationships of LMA and Narea to the light conditions were more pronounced within the climbers than within their supporters. Slope for the regression between climber's Narea and LMA was twice as steep as for the supporter leaves. Al accumulators were only found within the self-supporting vegetation. The investigated traits indicate improved adjustment towards light supply within climbers compared to self-supporting vegetation. Thus climbing plants seem to have a higher potential trade off in resource-use efficiency regarding irradiance and nutrients.

  16. Wieslander Vegetation

    California Department of Resources — 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...

  17. Fuzzy logic merger of spectral and ecological information for improved montane forest mapping.

    White, Joseph D.; Running, Steven W.; Ryan, Kevin C.; Key, Carl H.

    2002-01-01

    Environmental data are often utilized to guide interpretation of spectral information based on context, however, these are also important in deriving vegetation maps themselves, especially where ecological information can be mapped spatially. A vegetation classification procedure is presented which combines a classification of spectral data from Landsat‐5 Thematic Mapper (TM) and environmental data based on topography and fire history. These data were combined utilizing fuzzy logic where assignment of each pixel to a single vegetation category was derived comparing the partial membership of each vegetation category within spectral and environmental classes. Partial membership was assigned from canopy cover for forest types measured from field sampling. Initial classification of spectral and ecological data produced map accuracies of less than 50% due to overlap between spectrally similar vegetation and limited spatial precision for predicting local vegetation types solely from the ecological information. Combination of environmental data through fuzzy logic increased overall mapping accuracy (70%) in coniferous forest communities of northwestern Montana, USA.

  18. Invasive Plant-Soil Feedbacks and Ecosystem Resistance and Resilience: A Comparison of Three Vegetation Types in California

    Dickens, Sara Jo Myrtle

    2010-01-01

    ABSTRACT OF THE DISSERTATIONInvasive Plant-Soil Feedbacks and Ecosystem Resistance and Resilience: A Comparison of Three Vegetation Types in CaliforniaBy Sara Jo DickensDoctor of Philosophy, Graduate Program in Plant BiologyUniversity of California, Riverside, December 2010Dr Edith B. Allen, ChairpersonEcosystem processes are strongly dependant on plant-soil feedbacks. The invasion of exotic plant species can result in the introduction of novel traits capable of de-coupling native plant-soil ...

  19. Comparison modeling for alpine vegetation distribution in an arid area.

    Zhou, Jihua; Lai, Liming; Guan, Tianyu; Cai, Wetao; Gao, Nannan; Zhang, Xiaolong; Yang, Dawen; Cong, Zhentao; Zheng, Yuanrun

    2016-07-01

    Mapping and modeling vegetation distribution are fundamental topics in vegetation ecology. With the rise of powerful new statistical techniques and GIS tools, the development of predictive vegetation distribution models has increased rapidly. However, modeling alpine vegetation with high accuracy in arid areas is still a challenge because of the complexity and heterogeneity of the environment. Here, we used a set of 70 variables from ASTER GDEM, WorldClim, and Landsat-8 OLI (land surface albedo and spectral vegetation indices) data with decision tree (DT), maximum likelihood classification (MLC), and random forest (RF) models to discriminate the eight vegetation groups and 19 vegetation formations in the upper reaches of the Heihe River Basin in the Qilian Mountains, northwest China. The combination of variables clearly discriminated vegetation groups but failed to discriminate vegetation formations. Different variable combinations performed differently in each type of model, but the most consistently important parameter in alpine vegetation modeling was elevation. The best RF model was more accurate for vegetation modeling compared with the DT and MLC models for this alpine region, with an overall accuracy of 75 % and a kappa coefficient of 0.64 verified against field point data and an overall accuracy of 65 % and a kappa of 0.52 verified against vegetation map data. The accuracy of regional vegetation modeling differed depending on the variable combinations and models, resulting in different classifications for specific vegetation groups.

  20. Root Effect of Three Vegetation Types on Shoreline Stabilization of Chongming Island, Shanghai

    DU Qin; ZHONG Qi-Cheng; WANG Kai-Yun

    2010-01-01

    Coastal erosion is currently a major problem along the southern coast of Chongming Island, Shanghai. To enhance the erosion protection ability of coastal shelterbelts, two woody tree species, Taxodium ascendens and Salix babylonica, were planted separately into Phragmites australis + Scirpus mariqueter communities in 2006. Two years later, we investigated whether either of these experiments reduced erosion and increased stability in the native herbaceous plant community. We also examined soil stability and root length density under T. ascendens added, S. babylonica added and native herbaceous vegetation conditions along an intertidal gradient from the soil surface to a depth of 40 cm in each experiment, thus to determine the capacity of T. ascendens and S. babylonica to contribute to shoreline stabilization. Topsoil under the native vegetation had greater stability at the middle and higher intertidal zones because its soil stability index and root length density were significantly higher than in the T. ascendens or S. babylonica planted communities. The effect of T.ascendens on soil stability was not generally better than that of the native vegetation. Only at the 20-30 cm soil depth of the middle intertidal zone and in the 10-20 cm layer of the higher intertidal zone the soil stability index and root length densities under the T. ascendens added condition were significantly higher (P < 0.05) than those of the native vegetation.The S. babylonica planted soil had greater stability in the deeper soil layer than the soil under either the native vegetation or the T. ascendens added condition, and its soil stability index and root length density were significant higher (P < 0.05) than those of other vegetation conditions at the 30-40 cm soil depth for the lower intertidal zone and at the 20-40 cm layer for middle and higher intertidal zones.

  1. Perceived social-ecological factors associated with fruit and vegetable purchasing, preparation, and consumption among young adults.

    Graham, Dan J; Pelletier, Jennifer E; Neumark-Sztainer, Dianne; Lust, Katherine; Laska, Melissa N

    2013-10-01

    Most young adults do not consume recommended levels of fruits and vegetables (F/V), and interventions to increase F/V-related behaviors among this understudied population are needed. Therefore, it is important to identify correlates of F/V intake among young adults to guide intervention development. This cross-sectional study used data from an online survey to identify factors related to young adults' F/V purchasing, preparation, and consumption, and to explore between-factor relationships using mediation analysis. In 2010, 1,201 college students in Minnesota completed questionnaires assessing F/V behaviors as well as perceptions of F/V-related individual, social, and environmental factors. Factor analysis identified questionnaire items assessing similar constructs. Seven factors were identified (personal barriers, F/V knowledge, family, friends, neighborhood, access barriers, and campus) and evaluated for relationships with F/V purchasing, preparation, and consumption using linear regression. Results revealed that perceived personal barriers (eg, lacking cooking skills) were inversely related to all F/V outcomes. Perception that family and friends eat healthfully and neighborhood access to F/V were positively related to all outcomes. Individual-, social-, and environment-level perceptions were related to purchasing, preparation, and consumption, and the effects of these factors were similar when accounting for mediated effects. Factors at all three levels and the ways in which these various factors operate together may be important to consider in future efforts to improve F/V behaviors among young adults.

  2. Evaluation of vegetation types in the West Zagros (Beiranshahr region as a case study, in Lorestan Province, Iran

    ATENA ESLAMI FAROUJI

    2016-04-01

    Full Text Available Farouji AE, Khodayari H. 2016. Evaluation of vegetation types in the West Zagros (Beiranshahr region as a case study, in Lorestan Province, Iran. Biodiversita 17: 1-10. The accurate identification of plant communities and their distribution are classical tools for mapping and classification of plants. Plants are strongly sensitive against changing environmental conditions. Moreover, Iran has a special position in Asia which has been creating a diverse ecosystem. Close floristic studies are necessary for precise determination of diversity and uniformity. To determine plant species in different vegetation types in Beiran shahr region, modified multi-scale Whittaker plots were constructed. This studied area was about 20000 ha and located in Northwest to Southwest of Iran. Eighty-nine plots were made in different longitude and latitudes. The minimum and maximum heights were 1101 and 2489 m asl., respectively. Within each modified multi-scale plots, each species was explored. Of 608 species, 498 and 97 are belonging to dicotyledons and monocotyledons, and remained 13 species were Pteridophytes. As measured, Therophyte and Champhyte are the dominant and recessive form of life in studied area. Based on species of each plot and subplots, mean Jaccard's coefficient, number of unique species and mean unique species/plot were estimated for each vegetation type. It is obvious that there is a clear correlation between Slopes of the species-log area curve and Mean number of unique species per plot.

  3. Energy partitioning and environmental influence factors in different vegetation types in the GEWEX Asian Monsoon Experiment

    Liu, Fengshan; Tao, Fulu; Li, Shenggong; Zhang, Shuai; Xiao, Dengpan; Wang, Meng

    2014-12-01

    Environmental influences upon energy balance in areas of different vegetation types (i.e., forest at Kog-Ma in Thailand and at Yakutsk in Russia, grassland at Amdo in Chinese Tibet and at Arvaikheer in Mongolia, and mixed farmland at Tak in Thailand) in the GEWEX Asian Monsoon Experiment were investigated. The sites we investigated are geographically and climatologically different; and consequently had quite large variations in temperature ( T), water vapor pressure deficit (VPD), soil moisture (SM), and precipitation (PPT). During May-October, the net radiation flux ( R n) (in W·m-2) was 406.21 at Tak, 365.57 at Kog-Ma, 390.97 at Amdo, 316.65 at Arvaikheer, and 287.10 at Yakutsk. During the growing period, the R n partitioned into latent heat flux ( λE/ R n) was greater than that partitioned into sensible heat flux ( H/ R n) at Tak and at Kog-Ma. In contrast, λE/ R n was lower than H/ R n at Arvaikheer, H/ R n was less than λE/ R n between DOY 149 and DOY 270 at Amdo, and between DOY 165 and DOY 235 at Yakutsk. The R n partitioned into ground heat flux was generally less than 0.15. The short-wave albedo was 0.12, 0.18, and 0.20 at the forest, mixed land, and grass sites, respectively. At an hourly scale, energy partitions had no correlation with environmental factors, based on average summer halfhourly values. At a seasonal scale energy partitions were linearly correlated (usually p<0.05) with T, VPD, and SM. The λE/ R n increased with increases in SM, T, and VPD at forest areas. At mixed farmlands, λE/ R n generally had positive correlations with SM, T, and VPD, but was restrained at extremely high values of VPD and T. At grasslands, λE/ R n was enhanced with increases of SM and T, but was decreased with VPD.

  4. Effect of vegetation types on soil arbuscular mycorrhizal fungi and nitrogen-fixing bacterial communities in a karst region.

    Liang, Yueming; Pan, Fujing; He, Xunyang; Chen, Xiangbi; Su, Yirong

    2016-09-01

    Arbuscular mycorrhizal (AM) fungi and nitrogen-fixing bacteria play important roles in plant growth and recovery in degraded ecosystems. The desertification in karst regions has become more severe in recent decades. Evaluation of the fungal and bacterial diversity of such regions during vegetation restoration is required for effective protection and restoration in these regions. Therefore, we analyzed relationships among AM fungi and nitrogen-fixing bacteria abundances, plant species diversity, and soil properties in four typical ecosystems of vegetation restoration (tussock (TK), shrub (SB), secondary forest (SF), and primary forest (PF)) in a karst region of southwest China. Abundance of AM fungi and nitrogen-fixing bacteria, plant species diversity, and soil nutrient levels increased from the tussock to the primary forest. The AM fungus, nitrogen-fixing bacterium, and plant community composition differed significantly between vegetation types (p fungi and nitrogen-fixing bacteria, respectively. Available phosphorus, total nitrogen, and soil organic carbon levels and plant richness were positively correlated with the abundance of AM fungi and nitrogen-fixing bacteria (p fungi and nitrogen-fixing bacteria increased from the tussock to the primary forest and highlight the essentiality of these communities for vegetation restoration.

  5. Resource type influences the effects of reserves and connectivity on ecological functions.

    Yabsley, Nicholas A; Olds, Andrew D; Connolly, Rod M; Martin, Tyson S H; Gilby, Ben L; Maxwell, Paul S; Huijbers, Chantal M; Schoeman, David S; Schlacher, Thomas A

    2016-03-01

    Connectivity is a pivotal feature of landscapes that affects the structure of populations and the functioning of ecosystems. It is also a key consideration in conservation planning. But the potential functional effects of landscape connectivity are rarely evaluated in a conservation context. The removal of algae by herbivorous fish is a key ecological function on coral reefs that promotes coral growth and recruitment. Many reef herbivores are harvested and some use other habitats (like mangroves) as nurseries or feeding areas. Thus, the effects of habitat connectivity and marine reserves can jointly promote herbivore populations on coral reefs, thereby influencing reef health. We used a coral reef seascape in eastern Australia to test whether seascape connectivity and reserves influence herbivory. We measured herbivore abundance and rates of herbivory (on turf algae and macroalgae) on reefs that differed in both their level of connectivity to adjacent mangrove habitats and their level of protection from fishing. Reserves enhanced the biomass of herbivorous fish on coral reefs in all seascape settings and promoted consumption of turf algae. Consumption of turf algae was correlated with the biomass of surgeonfish that are exploited outside reserves. By contrast, both reserve status and connectivity influenced herbivory on macroalgae. Consumption of macroalgae was greatest on fished reefs that were far from mangroves and was not strongly correlated with any fish species. Our findings demonstrate that landscape connectivity and reserve status can jointly affect the functioning of ecosystems. Moreover, we show that reserve and connectivity effects can differ markedly depending on resource type (in this case turf algae vs. macroalgae). The effectiveness of conservation initiatives will therefore depend on our ability to understand how these multiple interactive effects structure the distribution of ecological functions. These findings have wider implications for the

  6. On the potential vegetation feedbacks that enhance phosphorus availability - insights from a process-based model linking geological and ecological timescales

    Buendía, C.; Arens, S.; Hickler, T.; Higgins, S. I.; Porada, P.; Kleidon, A.

    2014-07-01

    In old and heavily weathered soils, the availability of P might be so small that the primary production of plants is limited. However, plants have evolved several mechanisms to actively take up P from the soil or mine it to overcome this limitation. These mechanisms involve the active uptake of P mediated by mycorrhiza, biotic de-occlusion through root clusters, and the biotic enhancement of weathering through root exudation. The objective of this paper is to investigate how and where these processes contribute to alleviate P limitation on primary productivity. To do so, we propose a process-based model accounting for the major processes of the carbon, water, and P cycles including chemical weathering at the global scale. Implementing P limitation on biomass synthesis allows the assessment of the efficiencies of biomass production across different ecosystems. We use simulation experiments to assess the relative importance of the different uptake mechanisms to alleviate P limitation on biomass production. We find that active P uptake is an essential mechanism for sustaining P availability on long timescales, whereas biotic de-occlusion might serve as a buffer on timescales shorter than 10 000 yr. Although active P uptake is essential for reducing P losses by leaching, humid lowland soils reach P limitation after around 100 000 yr of soil evolution. Given the generalized modelling framework, our model results compare reasonably with observed or independently estimated patterns and ranges of P concentrations in soils and vegetation. Furthermore, our simulations suggest that P limitation might be an important driver of biomass production efficiency (the fraction of the gross primary productivity used for biomass growth), and that vegetation on old soils has a smaller biomass production rate when P becomes limiting. With this study, we provide a theoretical basis for investigating the responses of terrestrial ecosystems to P availability linking geological and

  7. Crestridge Vegetation Map [ds211

    California Department of Resources — This layer represents vegetation communities in the Department of Fish and Game's Crestridge Ecological Reserve. The County of San Diego, the Conservation Biology...

  8. Late Holocene vegetation dynamics and deforestation in Rano Aroi: Implications for Easter Island's ecological and cultural history

    Rull, Valentí; Cañellas-Boltà, Núria; Margalef, Olga; Sáez, Alberto; Pla-Rabes, Sergi; Giralt, Santiago

    2015-10-01

    Easter Island (Rapa Nui) has been considered an example of how societies can cause their own destruction through the overexploitation of natural resources. The flagship of this ecocidal paradigm is the supposed abrupt, island-wide deforestation that occurred about one millennium ago, a few centuries after the arrival of Polynesian settlers to the island. Other hypotheses attribute the forest demise to different causes such as fruit consumption by rats or aridity but the occurrence of an abrupt, island-wide deforestation during the last millennium has become paradigmatic in Rapa Nui. We argue that such a view can be questioned, as it is based on the palynological study of incomplete records, owing to the existence of major sedimentary gaps. Here, we present a multiproxy (pollen, charcoal and geochemistry) study of the Aroi core, the first gap-free sedimentary sequence of the last millennia obtained to date in the island. Our results show changing vegetation patterns under the action of either climatic or anthropogenic drivers, or both, depending on the time interval considered. Palm forests were present in Aroi until the 16th century, when deforestation started, coinciding with fire exacerbation -likely of human origin- and a dry climate. This is the latest deforestation event recorded so far in the island and took place roughly a century before European contact. In comparison to other Easter Island records, this record shows that deforestation was neither simultaneous nor proceeded at the same pace over the whole island. These findings suggest that Easter Island's deforestation was a heterogeneous process in space and time, and highlights the relevance of local catchment traits in the island's environmental and land management history.

  9. Predictors of College-Student Food Security and Fruit and Vegetable Intake Differ by Housing Type

    Mirabitur, Erica; Peterson, Karen E.; Rathz, Colleen; Matlen, Stacey; Kasper, Nicole

    2016-01-01

    Objective: We assessed whether college-student characteristics associate with food security and fruit and vegetable (FV) intake and whether these associations differ in students in housing with and without food provision. Participants: 514 randomly-sampled students from a large, Midwestern, public university in 2012 and 2013 Methods: Ordered…

  10. Effect of harvest at different times of day on the physical and chemical characteristics of vegetable-type soybean

    Andréia Cristina Santana

    2012-06-01

    Full Text Available The objective of this study was to evaluate the effect of harvest at different times of day on the chemical and physical characteristics of vegetable-type soybean BRS 267 cultivar, harvested at the R6 stage (seed development and to compare it with that on the grains harvested at the R8 stage (maturation. The pods of the BRS 267 cultivar were harvested at the R6 stage (at 8:00 AM, 12:00 AM, and 6:00 PM, the color parameters were evaluated, and the grains were analyzed for chemical composition, activity inhibitor trypsin, phytic acid content, starch, sugars, fatty acids, and isoflavones. No differences were observed among the different harvest times in terms of the chemical constituents of vegetable-type soybean BRS 267 cultivar harvested at the R6 stage. Isoflavones content did not change with different harvest times, and the aglycone forms (daidzein, glycitein, and genistein were found in smaller quantities at the R6 stage compared to the R8 stage. The color of the pods of soybean BRS 267 cultivar, harvested at the R6 stage did not change with different harvest times. The grains harvested at the R6 stage had lower protein content, phytic acid, and sucrose and higher levels of lipids, carbohydrates, starch, glucose, fructose, stachyose, and linolenic acids than those collected at the R8 stage. The different times of harvest did not affect the quality of the vegetable-type soybean BRS 267 cultivar harvested at stage R6. Nevertheless, it is recommended to harvest in the morning, when the temperature is milder, like other vegetables, to facilitate and optimize its marketing and in natura consumption.

  11. Vegetation Mapping of the Mond Protected Area of Bushehr Province (South-west Iran)

    Ahmadreza Mehrabian; Alireza Naqinezhad; Abdolrassoul Salman Mahiny; Hossein Mostafavi; Homan Liaghati; Mohsen Kouchekzadeh

    2009-01-01

    Add regions of the wodd occupy up to 35% of the earth's surface, the basis of various definitions of climatic conditions,vegetation types or potential for food production. Due to their high ecological value, monitoring of add regions is necessary and modem vegetation studies can help in the conservation and management of these areas. The use of remote sensing for mapping of desert vegetation is difficult due to mixing of the spectral reflectance of bright desert soils with the weak spectral response of sparse vegetation. We studied the vegetation types in the semiarid to arid region of Mond Protected Area, south-west Iran, based on unsupervised classification of the Spot XS bands and then produced updated maps.Sixteen map units covering t2 vegetation types were recognized in the area based on both field works and satellite mapping. Halocnemum strobilaceum and Suaeda fruticosa vegetation types were the dominant types and Ephedra foliata,Salicornia europaaa-Suaeda heterophylla vegetation types were the smallest. Vegetation coverage decreased sharply with the increase in salinity towards the coastal areas of the Persian Gulf. The highest vegetation coverage belonged to the riparian vegetation along the Mond River, which represents the northern boundary of the protected area. The location of vegetation types was studied on the separate soil and habitat diversity maps of the study area, which helped in final refinements of the vegetation map produced.

  12. Eddy covariance and scintillation measurements of atmospheric exchange processes over different types of vegetation

    Nieveen, J.P.

    1999-01-01

    Introduction and objectivesGood comprehension of the energy and mass cycles and their effect on climate dynamics is crucial to understanding, predicting and anticipating ecological changes due to possible future climate perturbations. Here direct and long-term flux density measurements of greenhouse

  13. Distribution of phytoplankton functional types in high-nitrate, low-chlorophyll waters in a new diagnostic ecological indicator model

    A. P. Palacz

    2013-11-01

    Full Text Available Modeling and monitoring plankton functional types (PFTs is challenged by the insufficient amount of field measurements of ground truths in both plankton models and bio-optical algorithms. In this study, we combine remote sensing data and a dynamic plankton model to simulate an ecologically sound spatial and temporal distribution of phyto-PFTs. We apply an innovative ecological indicator approach to modeling PFTs and focus on resolving the question of diatom–coccolithophore coexistence in the subpolar high-nitrate and low-chlorophyll regions. We choose an artificial neural network as our modeling framework because it has the potential to interpret complex nonlinear interactions governing complex adaptive systems, of which marine ecosystems are a prime example. Using ecological indicators that fulfill the criteria of measurability, sensitivity and specificity, we demonstrate that our diagnostic model correctly interprets some basic ecological rules similar to ones emerging from dynamic models. Our time series highlight a dynamic phyto-PFT community composition in all high-latitude areas and indicate seasonal coexistence of diatoms and coccolithophores. This observation, though consistent with in situ and remote sensing measurements, has so far not been captured by state-of-the-art dynamic models, which struggle to resolve this "paradox of the plankton". We conclude that an ecological indicator approach is useful for ecological modeling of phytoplankton and potentially higher trophic levels. Finally, we speculate that it could serve as a powerful tool in advancing ecosystem-based management of marine resources.

  14. Study on Types and Features of Urban Vegetation in Urumqi%乌鲁木齐城市植被类型及其特点

    尹林克; 南伟疆; 严成; 王蕾; 姜逢清; 昝勤

    2011-01-01

    根据人为干扰程度、群落功能以及优势建群种,将乌鲁木齐市城市植被划分为自然植被、半自然植被和人工植被3个植被类、13个植被组和125个植被型。自然植被类划分为7个植被组82个植被型;半自然植被类划分为4个植被组33个植被型;人工植被类划分为2个植被组10个植被型。乌鲁木齐自然植被类谱系完整,旱生和超旱生灌木、半灌木及多年生草本优势明显。半自然植被类由于人类活动的扰动,植物群落物种数量较自然植被明显增多,乔灌木比例加大,上层乔灌木种类大部分为人工栽培种,草本组多为原生和外来的野生植物种,部分物种呈斑块状分布并沿灌溉带呈线状分布,物种多样性指数较高。人工植被类中园林绿地破碎度较高,呈点、块、条状散布于城市中心,覆盖率低,种群间和群落间关联度小。其中,以防护林绿地为主,群落中引入归化种和外来种的比例过高;受市场经济影响,农业植被组以粮食、蔬菜和油料为主。%According to the degree of human disturbance,community functions and advantages of the dominant and constructive species,in this paper,urban vegetation in Urumqi was divided into three parts,i.e.the natural vegetation,semi-natural vegetation and artificial vegetation,including 3 vegetation races,13 vegetation groups and 125 vegetation types.Natural vegetation race is classified into 7 vegetation groups,i.e.the coniferous forest vegetation group,broadleaf forest vegetation group,shrub vegetation group,desert vegetation group,meadow vegetation group,steppe vegetation group and alpine vegetation group with 82 vegetation types;semi-natural vegetation race is divided into 4 vegetation groups,i.e.the broadleaf forest vegetation group,shrub vegetation group,herbaceous vegetation group and partner person vegetation group with 33 vegetation types;artificial vegetation race is classified into 2 vegetation groups

  15. [Comparison of soil fertility among open-pit mine reclaimed lands in Antaibao regenerated with different vegetation types].

    Wang, Xiang; Li, Jin-chuan; Yue, Jian-ying; Zhou, Xiao-mei; Guo, Chun-yan; Lu, Ning; Wang, Yu-hong; Yang, Sheng-quan

    2013-09-01

    Re-vegetation is mainly applied into regeneration in opencast mine to improve the soil quality. It is very important to choose feasible vegetation types for soil restoration. In this study, three typical forest restoration types were studied at Antaibao mine, namely, Medicago sativa, mixed forests Pinus taebelaefolius-Robinia pseudoacacia-Caragana korshinskii and Elaeagnus angustifolia-Robinia pseudoacacia-Caragana korshinskii-Hipophae rhamnoides, to determine the nutrient contents and enzyme activities in different soil layers. The results showed that re-vegetation markedly increased soil nutrient contents and the enzyme activities during the restoration process. The nutrient content of soil in the P. taebelaefolius-R. pseudoacacia-C. korshinskii mixed forest field was significantly higher than those in other plots. It was found that the soil of the P. taebelaefolius-R. pseudoacacia-C. korshinskii mixed forest had the highest integrated fertility index values. In conclusion, the restoration effects of the P. zaebelaefolius-R. pseudoacacia-C. Korshinskii mixed forest was better than that of E. angustifolia-R. pseudoacacia-C. korshinskii-H. rhamnoides, while M. sativa grassland had the least effect.

  16. Ecological recovery of vegetation on a coke-factory soil: role of plant antioxidant enzymes and possible implications in site restoration.

    Dazy, Marc; Jung, Vincent; Férard, Jean-François; Masfaraud, Jean-François

    2008-12-01

    The present paper investigated the short-term colonization by plants of a highly degraded soil in field conditions. The objectives were to identify, through phytosociological analysis, the plant species able to grow on such polluted areas and to characterize pollutant effects at different biological levels through analyses of plant oxidative status, plant growth or community indexes of richness and biodiversity. Our results showed that among the plants present in the uncontaminated surrounding area, only few species were able to colonize the polluted soil. These species were typical of the first years of grassland successions. Ecological indexes proved that the polluted soil vegetation presented a lower degree of species richness and biodiversity than the control area. These discrepancies were partly explained by pollutant phytotoxicity. Indeed, for several species including Erigeron canadensis and Oenothera biennis, we observed toxic effects of the polluted soil on plant height and biomass. Moreover, at the cellular level, changes in antioxidant enzyme activities (SOD, CAT, APX, GPX and GRD) and lipid peroxidation level (MDA) were observed. Such biochemical changes seemed to play an important role on plant sensitivity/tolerance to pollutants and thus to render them more or less competitive for colonization of such disturbed areas.

  17. Feed intake and activity level of two broiler genotypes foraging different types of vegetation in the finishing period

    Almeida, Gustavo Fonseca; Hinrichsen, Lena Karina; Horsted, Klaus;

    2012-01-01

    were included in a 2 × 2 factorial design with groups of 25 birds replicated 3 times. The use of outdoor areas, performance, and forage intake were investigated. To identify possible differences in foraging activity, the use of the range was monitored one day per week at 4 different times of the day......A study was performed with 2 broiler genotypes (slow and medium growth) restricted in supplementary feed and foraging 2 different mixed vegetations (grass/clover or chicory) to identify possible benefits of herbage on nutrition during the finishing period (80 to 113 d of age). Three hundred birds....... Feed intake from foraging was estimated by killing 4 birds per plot (2 males and 2 females) in the morning and in the evening on 3 d during the experiment and measuring crop content. Vegetation type did not influence broiler use of the free-range area, feed intake, or performance. Differences...

  18. Effect of non-crop vegetation types on conservation biological control of pests in olive groves

    2013-01-01

    Conservation biological control (CBC) is an environmentally sound potential alternative to the use of chemical insecticides. It involves modifications of the environment to promote natural enemy activity on pests. Despite many CBC studies increasing abundance of natural enemies, there are far fewer demonstrations of reduced pest density and very little work has been conducted in olive crops. In this study we investigated the effects of four forms of non-crop vegetation on the abundance of two...

  19. Soil carbon fractions and enzyme activities under different vegetation types on the Loess Plateau of China

    Zhang, Haixin; Zeng, Quanchao; An, Shaoshan; Dong, Yanghong; Darboux, Frédéric

    2016-01-01

    Vegetation restoration was effective way of protecting soil erosion and water conservation on the Loess Plateau. Carbon fractions and enzyme activities were sensitive parameters for assessment of soil remediation through revegetation. Forest, forest steppe and grassland soils were collected at 0–5 cm and 5–20 cm soil layers in Yanhe watershed, Shaanxi Province. Urease, sucrase, alkaline phosphatase, soil organic carbon (SOC), microbial biomass carbon (MBC), easily ox...

  20. Type utilization of baked-smashed sweet potato and vegetables on patisserie product

    Ana; Subekti, S.; Sudewi; Perdani, E. N.; Hanum, F.; Suciani, T.; Tania, V.

    2016-04-01

    The research was an experimental study in Green Skill Patisserie Course using Project-Based Learning model. It aims to complete the project development of pie named guramnis rainbow pie. Several experiments were carried out to produce a pie dough crust mixed with baked-smashed sweet potato and added with vegetables extract as the food coloring. The experiment method in order to make a better appearance or an attractive shape and to have more nutrition. In addition, the pie was filled with a mixture of sweet and sour gurame as Indonesian traditional food. By applying an organoleptic test to 10 respondents, the result shows that pie dough recipe using flour substituted by baked-smashed sweet potato with 2:1 of a ratio. Coloring pie dough adding extract vegetables (carrots, beets and celery) as color. We found that pie dough has more interesting pie color (90%) and the texture of the pie with a quite level of crispness (60%). Moreover, the pie taste is fairly (70%) and tasty (70%). Nutritional analysis results show that per size, serving guramnis rainbow pie contains energy as much as 81.72 calories, carbohydrates 12.5 grams, fat 2.32 grams and 2.77 grams of protein. The main findings are the pie appearance and taste was different compared to the previous pies because of the pie was served with gurame asam manis as the filling and had flour and cilembu sweet potato as the basic ingredients. The color of guramnis rainbow pie was resulted not only from food coloring but also from vegetables extract namely carrot (orange), bit (red), and salary (green). Thus, it had many benefits for health and adds the nutrition. The researchers recommend a further study in order to make pie dough with baked sweet potato and vegetables extract having an optimal level of crispness.

  1. Between Design and Ecology

    Bjørn, Mona Chor

    such vegetation, based on concepts and theories in plant community ecology. If these communities are based on local forbs there is a continuum in anthropogenic intervention from designed and intensively maintained to semi-natural herbaceous vegetation. Results from a large field experiment show that, after three...... colonised by grasses and eventually woody species. This thesis adds useful basic knowledge in plant community ecology and species-specific growth, which are relevant to research and planning in landscape architecture and ecology....

  2. Dissolved organic carbon (DOC) concentrations in UK soils and the influence of soil, vegetation type and seasonality.

    van den Berg, Leon J L; Shotbolt, Laura; Ashmore, Mike R

    2012-06-15

    Given the lack of studies which measured dissolved organic carbon (DOC) over long periods, especially in non-forest habitat, the aim of this study was to expand the existing datasets with data of mainly non-forest sites that were representative of the major soil and habitat types in the UK. A further aim was to predict DOC concentrations from a number of biotic and abiotic explanatory variables such as rainfall, temperature, vegetation type and soil type in a multivariate way. Pore water was sampled using Rhizon or Prenart samplers at two to three week intervals for 1 year. DOC, pH, organic carbon, carbon/nitrogen (C:N) ratios of soils and slope were measured and data on vegetation, soil type, temperature and precipitation were obtained. The majority of the variation in DOC concentrations between the UK sites could be explained by simple empirical models that included annual precipitation, and soil C:N ratio with precipitation being negatively related to DOC concentrations and C:N ratio being positively related to DOC concentrations. Our study adds significantly to the data reporting DOC concentrations in soils, especially in grasslands, heathlands and moorlands. Broad climatic and site factors have been identified as key factors influencing DOC concentrations.

  3. Simple and robust methods for remote sensing of canopy chlorophyll content: a comparative analysis of hyperspectral data for different types of vegetation.

    Inoue, Yoshio; Guérif, Martine; Baret, Frédéric; Skidmore, Andrew; Gitelson, Anatoly; Schlerf, Martin; Darvishzadeh, Roshanak; Olioso, Albert

    2016-12-01

    Canopy chlorophyll content (CCC) is an essential ecophysiological variable for photosynthetic functioning. Remote sensing of CCC is vital for a wide range of ecological and agricultural applications. The objectives of this study were to explore simple and robust algorithms for spectral assessment of CCC. Hyperspectral datasets for six vegetation types (rice, wheat, corn, soybean, sugar beet and natural grass) acquired in four locations (Japan, France, Italy and USA) were analysed. To explore the best predictive model, spectral index approaches using the entire wavebands and multivariable regression approaches were employed. The comprehensive analysis elucidated the accuracy, linearity, sensitivity and applicability of various spectral models. Multivariable regression models using many wavebands proved inferior in applicability to different datasets. A simple model using the ratio spectral index (RSI; R815, R704) with the reflectance at 815 and 704 nm showed the highest accuracy and applicability. Simulation analysis using a physically based reflectance model suggested the biophysical soundness of the results. The model would work as a robust algorithm for canopy-chlorophyll-metre and/or remote sensing of CCC in ecosystem and regional scales. The predictive-ability maps using hyperspectral data allow not only evaluation of the relative significance of wavebands in various sensors but also selection of the optimal wavelengths and effective bandwidths.

  4. Woody plants diversity and type of vegetation in non cultivated plain of Moutourwa, Far-North, Cameroon

    Gilbert Todou

    2016-12-01

    Full Text Available In order to valorize the wild vegetal resources for the efficient conservation and sustainable use in sahelo-sudanian zone in Cameroon, a study of non cultivated plain of Moutourwa was carry out to assess the floristic richness, the specific diversity and the type of vegetation. The inventory of all trees and shrubs (dbh ? 2.5 cm and the determination of the vegetation cover were done in five linear transects (20 m × 1000 m. In total, 27 families, 54 genera and 75 species were found. Caesalpinaceae is the most abundant family that relative abundance (pi*100 is 34.41%, the most abundant genus was Piliostigma (pi*100 = 30.66% and the most represented species was Piliostigma reticulatum (pi*100 = 29.56%; D = 53.6 stems/ha. The Simpson index (E= 0.89, the Shannon index (H= 3.2 and the equitability index of Pielou (J= 0.74 indicated that there were moderate diversity with more or less equitable species. The wild fruits species were numerous (pi*100 = 32.76%; D = 59.7 stems/ha. A. senegalensis is was the most represented (pi*100 = 9.04 ; D = 16.4 followed by Hexalobus monopetalus (pi*100 = 5.16 ; D = 9.4 and Balanites aegyptiaca (pi*100 = 3.69 ; D = 6.7. These results contribute efficaciously to valorize the wild vegetal resources for efficient conservation and sustainable use. Keywords: Woody plants diversity, conservation, sustainable use, sahelo-sudanian, Moutourwa

  5. The effect of vegetation type and fire on permafrost thaw: An empirical test of a process based model

    Thierry, Aaron; Estop-Aragones, Cristian; Fisher, James; Hartley, Iain; Murton, Julian; Phoenix, Gareth; Street, Lorna; Williams, Mathew

    2015-04-01

    As conditions become more favourable for plant growth in the high latitudes, most models predict that these areas will take up more carbon during the 21st century. However, vast stores of carbon are frozen in boreal and arctic permafrost, and warming may result in some of this carbon being released to the atmosphere. The recent inclusion of permafrost thaw in large-scale model simulations has suggested that the permafrost feedback could potentially substantially reduce the predicted global net uptake of carbon by terrestrial ecosystems, with major implications for the rate of climate change. However, large uncertainties remain in predicting rates of permafrost thaw and in determining the impacts of thaw in contrasting ecosystems, with many of the key processes missing from carbon-climate models. The role that different plant communities play in insulating soils and protecting permafrost is poorly quantified, with key groups such as mosses absent in many models. But it is thought that they may play a key role in determining permafrost resilience. In order to test the importance of these ecological processes we use a new specially acquired dataset from sites in the Canadian arctic to develop, parameterise and evaluate a detailed process-based model of vegetation-soil-permafrost interactions which includes an insulating moss understory. We tested the sensitivity of modelled active layer depth to a series of factors linked to fire disturbance, which is common in boreal permafrost areas. We show how simulations of active layer depth (ALD) respond to removals of (i) vascular vegetation, (ii) moss cover, and (iii) organic soil layers. We compare model responses to observed patterns from Canada. We also describe the sensitivity of our modelled ALD to changes in temperature and precipitation. We found that four parameters controlled most of the sensitivity in the modelled ALD, linked to conductivity of organic soils and mosses.

  6. Ecological Species Groups of Wetland Vegetation on Lianbotan in Fen River, Shanxi%汾河连伯滩湿地植被生态种组

    焦磊; 张峰

    2011-01-01

    根据42个野外样方调查资料,采用Fisher精确检验、Pearson相关系数和Spearman秩相关系数,研究汾河连伯滩湿地21个优势种的种间关系,结合组平均法的聚类结果,对生态种组进行了划分.结果表明:1)在210个种对中,Fisher精确检验结果表明共有16个种对为正关联,1个种对为负关联;Pearson相关系数有20个种对为正相关,5个种对为负相关;Spearman秩相关系数有34个种对为正相关,7个种对为负相关;2)在所有的种对中,大多数种对间表现为不显著关联,种间不显著相关,说明优势种群间生态位相对分离;3)综合种间关联、种间相关和聚类分析结果,将21个优势种划分成4个生态种组,分别是芦苇生态种组、赖草生态种组、白茅生态种组和野艾蒿生态种组,这4个生态种组反映了随水分条件变化连伯滩湿地植被群落的组成特征.%Interspecies relationships between the dominant species of wetland vegetation on Lianbotan in Fen River,Shanxi by Fishers exact test, Pearson's correlation coefficient and Spearman's rank correlation based on the data collected from 42 field plots. Ecological species groups of those dominant species were studied by using group averaging clustering.The results indicated that: Sixteen species-pairs had positive association coefficient and one species-pair had negative association coefficient by Fisher's exact test. In addition, 20 species-pairs had positive correlation coefficient and 5 species-pairs had negative correlation coefficient by Pearson's correlation analysis. Furthermore, 34 species-pairs displayed positive and 7 were negative correlations by Spearman. Associations and correlations between most species-pairs were not significant, which suggested that the dominant species distributed in an isolated pattern and their inches separated. On the basis of the results of association and correlation of those dominant species as well as that of analysis of clustering, those

  7. Ecological studies on rain forest in Northern Suriname

    Schulz, J.P.

    1960-01-01

    During the years 1955-1957 ecological data were collected in various types of mesophytic forest occurring in the northern half of central Suriname (fig. 1). Physiognomically as well as floristically these forests correspond with the type of vegetation which in the other parts of tropical America gen

  8. Effect of Different Vegetation Types on the Rhizosphere Soil Microbial Community Structure in the Loess Plateau of China

    ZHANG Chao; LIU Guo-bin; XUE Sha; and XIAO Lie

    2013-01-01

    The Loess Plateau in China is one of the most eroded areas in the world. Accordingly, vegetation restoration has been implemented in this area over the past two decades to remedy the soil degradation problem. Understanding the microbial community structure is essential for the sustainability of ecosystems and for the reclamation of degraded arable land. This study aimed to determine the effect of different vegetation types on microbial processes and community structure in rhizosphere soils in the Loess Plateau. The six vegetation types were as follows:two natural grassland (Artemisia capillaries and Heteropappus altaicus), two artificial grassland (Astragalus adsurgens and Panicum virgatum), and two artificial shrubland (Caragana korshinskii and Hippophae rhamnoides) species. The microbial community structure and functional diversity were examined by analyzing the phospholipid fatty acids (PLFAs) and community-level physiological profiles. The results showed that rhizosphere soil sampled from the H. altaicus and A. capillaries plots had the highest values of microbial biomass C, average well color development of carbon resources, Gram-negative (G-) bacterial PLFA, bacterial PLFA, total PLFA, Shannon richness, and Shannon evenness, as well as the lowest metabolic quotient. Soil sampled from the H. rhamnoides plots had the highest metabolic quotient and Gram-positive (G+) bacterial PLFA, and soil sampled from the A. adsurgens and A. capillaries plots had the highest fungal PLFA and fungal:bacterial PLFA ratio. Correlation analysis indicated a signiifcant positive relationship among the microbial biomass C, G- bacterial PLFA, bacterial PLFA, and total PLFA. In conclusion, plant species under arid climatic conditions signiifcantly affected the microbial community structure in rhizosphere soil. Among the studied plants, natural grassland species generated the most favorable microbial conditions.

  9. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China.

    Niu, Xiang; Gao, Peng; Wang, Bing; Liu, Yu

    2015-12-03

    Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD) and soil water retention curve (WRC) under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1) the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM) > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM) > Pinus thunbergii Parl. (PTP) > Juglans rigia Linn. (JRL) > abandoned grassland (ABG); (2) the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL) were significantly higher than that in ABG, and mixed forests (QRM and PPM) were higher than that in pure forests (PTP and JRL); (3) the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4) the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure.

  10. Influence of animal fat substitution by vegetal fat on Mortadella-type products formulated with different hydrocolloids

    Erick Saldaña

    2015-12-01

    Full Text Available Meat has played a crucial role in human evolution and is an important component of a healthy and well-balanced diet on account of its nutritional properties, its high biological value as a source of protein, and the vitamins and minerals it supplies. We studied the effects of animal fat reduction and substitution by hydrogenated vegetal fat, sodium alginate and guar gum. Fatty acid composition, lipid oxidation, color and instrumental texture as well as the sensorial difference between low, substituted-fat and the traditional formulations for mortadella-type products were analyzed. Both substitution and reduction of animal fat decreased the saturated fatty acids percentage from 40% down to 31%. A texture profile analysis showed differences between the formulations. Furthermore, lipid oxidation values were not significant for treatments as regards the type and quantity of fat used while the use of sodium alginate and guar gum reduced the amounts of liquid released after cooking. Animal fat substitution does cause, however, a difference in overall sensorial perception compared with non-substituted products. The results confirm the viability of substituting vegetal fat for animal fat.

  11. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China

    Xiang Niu

    2015-12-01

    Full Text Available Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD and soil water retention curve (WRC under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1 the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM > Pinus thunbergii Parl. (PTP > Juglans rigia Linn. (JRL > abandoned grassland (ABG; (2 the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL were significantly higher than that in ABG, and mixed forests (QRM and PPM were higher than that in pure forests (PTP and JRL; (3 the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4 the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure.

  12. Evaluation of sensor types and environmental controls on mapping biomass of coastal marsh emergent vegetation

    Byrd, Kristin B.; O'Connell, Jessica L.; Di Tommaso, Stefania; Kelly, Maggi

    2014-01-01

    There is a need to quantify large-scale plant productivity in coastal marshes to understand marsh resilience to sea level rise, to help define eligibility for carbon offset credits, and to monitor impacts from land use, eutrophication and contamination. Remote monitoring of aboveground biomass of emergent wetland vegetation will help address this need. Differences in sensor spatial resolution, bandwidth, temporal frequency and cost constrain the accuracy of biomass maps produced for management applications. In addition the use of vegetation indices to map biomass may not be effective in wetlands due to confounding effects of water inundation on spectral reflectance. To address these challenges, we used partial least squares regression to select optimal spectral features in situ and with satellite reflectance data to develop predictive models of aboveground biomass for common emergent freshwater marsh species, Typha spp. and Schoenoplectus acutus, at two restored marshes in the Sacramento–San Joaquin River Delta, California, USA. We used field spectrometer data to test model errors associated with hyperspectral narrowbands and multispectral broadbands, the influence of water inundation on prediction accuracy, and the ability to develop species specific models. We used Hyperion data, Digital Globe World View-2 (WV-2) data, and Landsat 7 data to scale up the best statistical models of biomass. Field spectrometer-based models of the full dataset showed that narrowband reflectance data predicted biomass somewhat, though not significantly better than broadband reflectance data [R2 = 0.46 and percent normalized RMSE (%RMSE) = 16% for narrowband models]. However hyperspectral first derivative reflectance spectra best predicted biomass for plots where water levels were less than 15 cm (R2 = 0.69, %RMSE = 12.6%). In species-specific models, error rates differed by species (Typha spp.: %RMSE = 18.5%; S. acutus: %RMSE = 24.9%), likely due to the more vertical structure and

  13. Impacts of climate gradients on the vegetation phenology of major land use types in Central Asia (1981-2008)

    Jahan KARIYEVA; Willem J.D.van LEEUWEN; Connie A.WOODHOUSE

    2012-01-01

    Time-series of land surface phenology (LSP)data offer insights about vegetation growth patterns.They can be generated by exploiting the temporal and spectral reflectance properties of land surface components.Interannual and seasonal LSP data are important for understanding and predicting an ecosystem's response to variations caused by natural and anthropogenic drivers.This research examines spatio-temporal change patterns and interactions between terrestrial phenology and 28 years of climate dynamics in Central Asia.Long-term (1981-2008) LSP records such as timing of the start,peak and length of the growing season and vegetation productivity were derived from remotely sensed vegetation greenness data.The patterns were analyzed to identify and characterize the impact of climate drivers at regional scales.We explored the relationships between phenological and precipitation and temperature variables for three generalized land use types that were exposed to decadelong regional drought events and intensified land and water resource use:rainfed agriculture,irrigated agriculture,and non-agriculture.To determine whether and how LSP dynamics are associated with climate patterns,a series of simple linear regression analyses between these two variables was executed.The three land use classes showed unique phenological responses to climate variation across Central Asia.Most of the phenological response variables were shown to be positively correlated to precipitation and negatively correlated to temperature.The most substantial climate variable affecting phenological responses of all three land use classes was a spring temperature regime.These results indicate that future higher temperatures would cause earlier and longer growing seasons.

  14. The impact of greenhouse vegetable farming duration and soil types on phytoavailability of heavy metals and their health risk in eastern China.

    Yang, Lanqin; Huang, Biao; Hu, Wenyou; Chen, Yong; Mao, Mingcui; Yao, Lipeng

    2014-05-01

    Heavy metal contamination in vegetables from greenhouse vegetable production (GVP) in China requires major attention. For GVP sustainability at a large regional level, 441 surface GVP soil and 132 corresponding greenhouse vegetable samples were collected from six typical GVP bases in eastern China to systematically evaluate the impact of GVP duration and soil types (Anthrosols and Cambosols) on phytoavailability of four major metals, Cd, Cu, Zn, and Pb, and their health risk. The results revealed high Cd accumulation in leaf vegetables grown in Anthrosols, which might pose potential health risk. Regardless of soil types in the study region, greenhouse farming lowered soil pH and enhanced metal availability with rising GVP duration, which might exacerbate Cd phytoavailability and vegetable Cd contamination as well as potential health risk. Also, increased GVP soil organic matter contents over time, found in some locations, affected crop-depending Cu and Zn uptakes. Furthermore, due to GVP, the annual decrease rate of soil pH and increase rates of soil available metal concentrations were generally much greater in Anthrosols than those in Cambosols, which contributed a lot to high Cd uptake by leaf vegetables grown in Anthrosols and their potential health risk. From sustainable GVP perspective, fertilization strategy with reduced frequency and rate is especially important and effective for abating soil and vegetable contamination by heavy metals under greenhouse farming.

  15. Tidal saline wetland regeneration of sentinel vegetation types in the Northern Gulf of Mexico: An overview

    Jones, Scott F.; Stagg, Camille L.; Krauss, Ken W.; Hester, Mark W.

    2016-06-01

    Tidal saline wetlands in the Northern Gulf of Mexico (NGoM) are dynamic and frequently disturbed systems that provide myriad ecosystem services. For these services to be sustained, dominant macrophytes must continuously recolonize and establish after disturbance. Macrophytes accomplish this regeneration through combinations of vegetative propagation and sexual reproduction, the relative importance of which varies by species. Concurrently, tidal saline wetland systems experience both anthropogenic and natural hydrologic alterations, such as levee construction, sea-level rise, storm impacts, and restoration activities. These hydrologic alterations can affect the success of plant regeneration, leading to large-scale, variable changes in ecosystem structure and function. This review describes the specific regeneration requirements of four dominant coastal wetland macrophytes along the NGoM (Spartina alterniflora, Avicennia germinans, Juncus roemerianus, and Batis maritima) and compares them with current hydrologic alterations to provide insights into potential future changes in dominant ecosystem structure and function and to highlight knowledge gaps in the current literature that need to be addressed.

  16. Tidal saline wetland regeneration of sentinel vegetation types in the Northern Gulf of Mexico: An overview

    Jones, Scott F; Stagg, Camille L.; Krauss, Ken W.; Hester, Mark W.

    2016-01-01

    Tidal saline wetlands in the Northern Gulf of Mexico (NGoM) are dynamic and frequently disturbed systems that provide myriad ecosystem services. For these services to be sustained, dominant macrophytes must continuously recolonize and establish after disturbance. Macrophytes accomplish this regeneration through combinations of vegetative propagation and sexual reproduction, the relative importance of which varies by species. Concurrently, tidal saline wetland systems experience both anthropogenic and natural hydrologic alterations, such as levee construction, sea-level rise, storm impacts, and restoration activities. These hydrologic alterations can affect the success of plant regeneration, leading to large-scale, variable changes in ecosystem structure and function. This review describes the specific regeneration requirements of four dominant coastal wetland macrophytes along the NGoM (Spartina alterniflora, Avicennia germinans, Juncus roemerianus, and Batis maritima) and compares them with current hydrologic alterations to provide insights into potential future changes in dominant ecosystem structure and function and to highlight knowledge gaps in the current literature that need to be addressed.

  17. Design and Development of a Spectral Library for Different Vegetation and Landcover Types for Arctic, Antarctic and Chihuahua Desert Ecosystem

    Matharasi, K.; Goswami, S.; Gamon, J.; Vargas, S.; Marin, R.; Lin, D.; Tweedie, C. E.

    2008-12-01

    All objects on the Earth's surface absorb and reflect portions of the electromagnetic spectrum. Depending on the composition of the material, every material has its characteristic spectral profile. The characteristic spectral profile for vegetation is often used to study how vegetation patterns at large spatial scales affect ecosystem structure and function. Analysis of spectroscopic data from the laboratory, and from various other platforms like aircraft or spacecraft, requires a knowledge base that consists of different characteristic spectral profiles for known different materials. This study reports on establishment of an online and searchable spectral library for a range of plant species and landcover types in the Arctic, Anatarctic and Chihuahuan desert ecosystems. Field data were collected from Arctic Alaska, the Antarctic Peninsula and the Chihuahuan desert in the visible to near infrared (IR) range using a handheld portable spectrometer. The data have been archived in a database created using postgre sql with have been made publicly available on a plone web-interface. This poster describes the data collected in more detail and offers instruction to users who wish to make use of this free online resource.

  18. Vegetation Spatial Heterogeneity of Different Soil Regions in Inner Mongolia, China

    2007-01-01

    The vegetation spatial heterogeneity and ecological characteristics in different soil regions were analyzed by surveying the vegetation in 12 different soil regions of Inner Mongolia, China, including coniferous-broadleaf deciduous forests, shrub, grassland, and desert regions with 1122 large 2 cm × 2 cm quadrats (actual size 30 km × 30 km, referred to as L-quadrat hereafter) in about 1.18 million km2. Each Lquadrat was divided into four small 1 cm× 1 cm quadrats (actual size 15 km × 15 km, S-quadrat). The vegetation was analyzed based on the beta-binomial distribution to describe the frequency of occurrence and spatial heterogeneity for each kind of vegetation. The weighted average of the heterogeneity of all vegetation in the same soil region provides a measure of the soil regional landscape level heterogeneity which describes the spatial complexity of the regional landscape composition of the existing vegetation. Comparison of the vegetation characteristics in the 12 soil regions shows that, the calcic gray soil has the highest average vegetation type per quadrat. The largest soil region is calcic chestnut soil and has the most vegetation types. Every soil region has its own dominant vegetation sequence which dominates in occurrence and dominant vegetation types which dominates in spatial heterogeneity. For the Inner Mongolian vegetation, the weighted average of the heterogeneity is 0.60 and the vegetation diversity index is 4.47.

  19. Remote sensing-based vegetation indices for monitoring vegetation change in the semi-arid region of Sudan

    R. A., Majdaldin; Osunmadewa, B. A.; Csaplovics, E.; Aralova, D.

    2016-10-01

    Land degradation, a phenomenon referring to (drought) in arid, semi-arid and dry sub-humid regions as a result of climatic variations and anthropogenic activities most especially in the semi-arid lands of Sudan, where vast majority of the rural population depend solely on agriculture and pasture for their daily livelihood, the ecological pattern had been greatly influenced thereby leading to loss of vegetation cover coupled with climatic variability and replacement of the natural tree composition with invasive mesquite species. The principal aim of this study is to quantitatively examine the vigour of vegetation in Sudan through different vegetation indices. The assessment was done based on indicators such as soil adjusted vegetation index (SAVI). Cloud free multi-spectral remotely sensed data from LANDSAT imagery for the dry season periods of 1984 and 2009 were used in this study. Results of this study shows conversion of vegetation to other land use type. In general, an increase in area covered by vegetation was observed from the NDVI results of 2009 which is a contrast of that of 1984. The results of the vegetation indices for NDVI in 1984 (vegetated area) showed that about 21% was covered by vegetation while 49% of the area were covered with vegetation in 2009. Similar increase in vegetated area were observed from the result of SAVI. The decrease in vegetation observed in 1984 is as a result of extensive drought period which affects vegetation productivity thereby accelerating expansion of bare surfaces and sand accumulation. Although, increase in vegetated area were observed from the result of this study, this increase has a negative impact as the natural vegetation are degraded due to human induced activities which gradually led to the replacement of the natural vegetation with invasive tree species. The results of the study shows that NDVI perform better than by SAVI.

  20. [Characteristics of soil pH and exchangeable acidity in red soil profile under different vegetation types].

    Ji, Gang; Xu, Ming-gang; Wen, Shi-lin; Wang, Bo-ren; Zhang, Lu; Liu, Li-sheng

    2015-09-01

    The characteristics of soil pH and exchangeable acidity in soil profile under different vegetation types were studied in hilly red soil regions of southern Hunan Province, China. The soil samples from red soil profiles within 0-100 cm depth at fertilized plots and unfertilized plots were collected and analyzed to understand the profile distribution of soil pH and exchangeable acidity. The results showed that, pH in 0-60 cm soil from the fertilized plots decreased as the following sequence: citrus orchard > Arachis hypogaea field > tea garden. As for exchangeable acidity content, the sequence was A. hypogaea field ≤ citrus orchard soil (0-40 cm), compared with the deep soil (60-100 cm), and soil pH decreased by 0.55 and 0.17 respectively, but such changes did not occur in citrus orchard. Soil pH in 0-40 cm soil from the natural recovery vegetation unfertilized plots decreased as the following sequence: Imperata cylindrica land > Castanea mollissima garden > Pinus elliottii forest ≥ Loropetalum chinensis forest. As for exchangeable acidity content, the sequence was L cylindrica land Soil pH in surface soil (0-20 cm) from natural forest plots, secondary forest and Camellia oleifera forest were significantly lower than that from P. massoniana forest, decreased by 0.34 and 0.20 respectively. For exchangeable acidity content in 0-20 cm soil from natural forest plot, P. massoniana forest and secondary forest were significantly lower than C. oleifera forest. Compared with bare land, surface soil acidification in unfertilized plots except I. cylindrica land had been accelerated, and the natural secondary forest was the most serious among them, with surface soil pH decreasing by 0.52. However, the pH increased in deep soils from unfertilized plots except natural secondary forest, and I. cylindrica land was the most obvious among them, with soil pH increasing by 0.43. The effects of fertilization and vegetation type on pH and exchangeable acidity decreased with the

  1. Litter flammability of French Mediterranean vegetation types : a cross-substratum analysis

    Curt, T.; Schaffhauser, A.; Borgniet, L.; Esteve, R.; Ganteaume, A.; Jappiot, M.; Lampin-Maillet, C.; Martin, W.; N'Diaye, A

    2010-01-01

    International audience; Assessing the flammability of litters in fire-prone ecosystems of major importance to quantify the wildland fire hazard. We compared undisturbed litter samples typical of French ecosystems on the two main types of substratum, i.e. acidic versus limestone, to investigate to which extent their characteristics and flammability may differ. We measured in the laboratory several flammability parameters on oven-dried samples that mimic the high fire hazard level in summer. On...

  2. [Consumption of nuts and vegetal oil in people with type 1 diabetes mellitus].

    Ferrer-García, Juan Carlos; Granell Vidal, Lina; Muñoz Izquierdo, Amparo; Sánchez Juan, Carlos

    2015-06-01

    Introducción: estudios recientes han demostrado los beneficios cardiovasculares de la dieta mediterránea enriquecida con aceite de oliva y frutos secos. Las personas con diabetes, que tienen un mayor riesgo de complicaciones cardiovasculares, podrían beneficiarse en gran medida de seguir ese tipo de patrón alimentario. Objetivos: análisis de la ingesta de grasas vegetales procedentes de frutos secos y aceites vegetales en pacientes con diabetes mellitus tipo 1 (DM1). Métodos: estudio transversal descriptivo que compara 60 personas con DM1 y 60 sujetos sanos. Se recoge la frecuencia de consumo de aceites vegetales y de frutos secos y se calcula el aporte procedente de estos alimentos en ácidos grasos mono y poliinsaturados (ácido oleico, linoleico y -linolénico). Se utilizó un cuestionario de frecuencia de consumo diseñado de forma específica. Se recogen variables antropométricas, factores de riesgo cardiovascular y variables relacionadas con la diabetes. Resultados: el consumo total de grasa vegetal procedente de aceites vegetales fue similar en los pacientes con DM1 frente a los sujetos control (3,02 ± 1,14 vs. 3,07 ± 1,27 Raciones (R)/día, P = 0,822) y de frutos secos (1,35 ± 2,24 vs. 1,60 ± 2,44 R/semana, P = 0,560). El grupo DM1 consumió menos aceite de oliva que el grupo control (2,55 ± 1,17 vs. 3,02 ± 1,34 R/día, P = 0,046). Se detectó un menor consumo de ácido -linolénico respecto al grupo control (1,13 ± 2,06 vs. 2,64 ± 4,37 g/día, P = 0,018), mientras que no hubo diferencias en el resto de ácidos grasos (oleico 28,30 ± 18,13 vs. 29,53 ± 16,90 g/día, P = 0,703; linoleico 13,70 ± 16,80 vs. 15,45 ± 19,90 g/día, P = 0,605). En los DM1 no se demostró una influencia del consumo de las grasas vegetales procedentes de aceites y frutos secos en los parámetros antropométricos, metabólicos y variables específicas de la diabetes. Conclusiones: en las personas con DM1 el consumo total de aceites vegetales y frutos secos no

  3. Nitrogen–use efficiency in different vegetation type at Cikaniki Research Station, Halimun-Salak Mountain National Park, West Java

    SUHARNO

    2007-10-01

    Full Text Available A research about nitrogen–use efficiency (NUE and trees identification was conducted at different vegetation type at Cikaniki, Halimun-Salak National Park, West Java. Plot quadrate methods (20 x 50 m was used to analyze trees vegetation and Kjeldahl methods was used to analyze leaf nitrogen. The width and length of the leaf was also measured to obtain the leaf surface area. The result showed that there are 61 individual trees which consisted of 24 species was identified. The species which have 5 highest important value are Altingia excelsa (64,657, Castanopsis javanica (39,698, Platea latifolia (27,684, Garcinia rostrata (21,151, and Schima walichii (16,049. Futhermore Eugenia lineata (13,967, Melanochyla caesa (12,241, Quercus lineata (10,766, platea excelsa (10,766 have lower important value. Other trees have important value less than 10. Morphological and nitrogen content analyze were done on 4 species : Quercus lineata, G. rostrata, A. excelsa, and E. lineata. Among them, Quercus lineata has highest specific leaf area (SLA (0,01153, followed by G. rostrata (0,00821, A. excelsa (0,00579, and E. lineata (0,00984 g/cm2. The highest number of stomata was found on A. excelsa (85,10/mm2, followed by E. lineata (74,40/mm2, Q. lineata (53,70/mm2, and G. rostrata (18,4 /mm2. The emergent species (A. excelsa and Q. lineata have higher nitrogen content than the underlayer species (G. rostrata and E. lineata. A. excelsa have highest nitrogen use efficiency (28,19% compare to E. lineata (23,81% , Q. lineata (19,09%, and G. rostrata (14,87%. Although not significant, emergen species have higher NUE than underlayer species.

  4. Spatial-seasonal variation of soil denitrification under three riparian vegetation types around the Dianchi Lake in Yunnan, China.

    Wang, Shaojun; Cao, Zilin; Li, Xiaoying; Liao, Zhouyu; Hu, Binghui; Ni, Jie; Ruan, Honghua

    2013-05-01

    Outbreaks of nuisance cyanobacterial bloom are predicted to occur frequently under the effect of severe eutrophication in the water body of Lake Dianchi since the 1990s. Riparian buffers are now well recognized for their roles in the removal of inorganic nitrogen mainly via denitrification. Little is known, however, about the mechanisms of nitrate removal in the riparian buffers of Lake Dianchi. We investigated the wet and dry seasonal dynamics of denitrification rate (DNR) in the soil profiles along the topographic gradient in three riparian buffers with different vegetation types (i.e. forest, open forest, and grass). A strong vertical pattern was observed in soil organic C and N concentrations (i.e. total N, DON, NO3-N, and NH4-N) along the soil layers. We also found significantly higher in situ denitrification activity in the upper horizon along each topohydrosequence while the activities of soil denitrification could be detected down to deeper soil horizons (0.1 to 0.8 mg N per kg dry soil per day), which may contribute significantly to the reduction of the ground water nitrate. Meanwhile, the DNR in the zones near the lake was significantly higher than that in zones near the border with the upland terrace, and also in the wet seasons than in dry seasons. Denitrification rates in the forest, open forest and grass sites were significantly different only in wet seasons. Especially, we found soil organic C had a strong correlation with denitrification in all sites, despite the large intersite variability of soil and vegetation. Our data suggested spatial heterogeneity of substrate availability along a hydrologic and topographic gradient can be the primary control on spatial-seasonal patterns of denitrification in riparian buffers.

  5. Soil respiration at mean annual temperature predicts annual total across vegetation types and biomes

    M. Bahn

    2009-12-01

    Full Text Available Soil respiration (SR constitutes the largest flux of CO2 from terrestrial ecosystems to the atmosphere. There still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 72 site-years for 58 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SR MAT, irrespective of the type of ecosystem and biome. This convergence is to be theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q10. We further show that for seasonally dry sites where annual precipitation (P is lower than potential evapotranspiration (PET, annual SR can be predicted from wet season SR MAT corrected for a factor related to P/PET. Our finding indicates that it is sufficient to measure SR MAT for obtaining a highly constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution and interannual variation of soil CO2 emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatio-temporal resolution of a major component of the global carbon cycle.

  6. Soil respiration at mean annual temperature predicts annual total across vegetation types and biomes

    M. Bahn

    2010-07-01

    Full Text Available Soil respiration (SR constitutes the largest flux of CO2 from terrestrial ecosystems to the atmosphere. However, there still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 80 site-years for 57 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SRMAT, irrespective of the type of ecosystem and biome. This is theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q10. We further show that for seasonally dry sites where annual precipitation (P is lower than potential evapotranspiration (PET, annual SR can be predicted from wet season SRMAT corrected for a factor related to P/PET. Our finding indicates that it can be sufficient to measure SRMAT for obtaining a well constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution of soil CO2 emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatial resolution of a major component of the global carbon cycle.

  7. Spatiotemporal variations of vegetation cover on the Chinese Loess Plateau(1981―2006):Impacts of climate changes and human activities

    2008-01-01

    Spatiotemporal variations of Chinese Loess Plateau vegetation cover during 1981-2006 have been investigated using GIMMS and SPOT VGT NDVI data and the cause of vegetation cover changes has been analyzed, considering the climate changes and human activities. Vegetation cover changes on the Loess Plateau have experienced four stages as follows: (1) vegetation cover showed a continued increasing phase during 1981―1989; (2) vegetation cover changes came into a relative steady phase with small fluctuations during 1990―1998; (3) vegetation cover declined rapidly during 1999―2001; and (4) vegetation cover increased rapidly during 2002―2006. The vegetation cover changes of the Loess Plateau show a notable spatial difference. The vegetation cover has obviously increased in the Inner Mongolia and Ningxia plain along the Yellow River and the ecological rehabilitated region of Ordos Plateau, however the vegetation cover evidently decreased in the hilly and gully areas of Loess Plateau, Liupan Mountains region and the northern hillside of Qinling Mountains. The response of NDVI to climate changes varied with different vegetation types. NDVI of sandy land vegetation, grassland and cultivated land show a significant increasing trend, but forest shows a decreasing trend. The results obtained in this study show that the spatiotemporal variations of vegetation cover are the outcome of climate changes and human activities. Temperature is a control factor of the seasonal change of vegetation growth. The increased temperature makes soil drier and unfavors vegetation growth in summer, but it favors vegetation growth in spring and autumn because of a longer growing period. There is a significant correlation between vegetation cover and precipitation and thus, the change in precipitation is an important factor for vegetation variation. The improved agricultural production has resulted in an increase of NDVI in the farmland, and the implementation of large-scale vegetation

  8. Spatiotemporal variations of vegetation cover on the Chinese Loess Plateau (1981―2006): Impacts of climate changes and human activities

    2008-01-01

    Spatiotemporal variations of Chinese Loess Plateau vegetation cover during 1981-2006 have been investigated using GIMMS and SPOT VGT NDVI data and the cause of vegetation cover changes has been analyzed, considering the climate changes and human activities. Vegetation cover changes on the Loess Plateau have experienced four stages as follows: (1) vegetation cover showed a continued increasing phase during 1981-1989; (2) vegetation cover changes came into a relative steady phase with small fluctuations during 1990-1998; (3) vegetation cover declined rapidly during 1999-2001; and (4) vegetation cover increased rapidly during 2002-2006. The vegetation cover changes of the Loess Plateau show a notable spatial difference. The vegetation cover has obviously increased in the Inner Mongolia and Ningxia plain along the Yellow River and the ecological rehabilitated region of Ordos Plateau, however the vegetation cover evidently decreased in the hilly and gully areas of Loess Plateau, Liupan Mountains region and the northern hillside of Qinling Mountains. The response of NDVI to climate changes varied with different vegetation types. NDVI of sandy land vegetation, grassland and cultivated land show a significant increasing trend, but forest shows a decreasing trend. The results obtained in this study show that the spatiotemporal variations of vegetation cover are the outcome of climate changes and human activities. Temperature is a control factor of the seasonal change of vegetation growth. The increased temperature makes soil drier and unfavors vegetation growth in summer, but it favors vegetation growth in spring and autumn because of a longer growing period. There is a significant correlation between vegetation cover and precipitation and thus, the change in precipitation is an important factor for vegetation variation. The improved agricultural production has resulted in an increase of NDVI in the farmland, and the implementation of large-scale vegetation construction has

  9. Four types of interference competition and their impacts on the ecology and evolution of size-structured populations and communities.

    Zhang, Lai; Andersen, Ken H; Dieckmann, Ulf; Brännström, Åke

    2015-09-07

    We investigate how four types of interference competition - which alternatively affect foraging, metabolism, survival, and reproduction - impact the ecology and evolution of size-structured populations. Even though all four types of interference competition reduce population biomass, interference competition at intermediate intensity sometimes significantly increases the abundance of adult individuals and the population׳s reproduction rate. We find that foraging and metabolic interference evolutionarily favor smaller maturation size when interference is weak and larger maturation size when interference is strong. The evolutionary response to survival interference and reproductive interference is always larger maturation size. We also investigate how the four types of interference competition impact the evolutionary dynamics and resultant diversity and trophic structure of size-structured communities. Like other types of trait-mediated competition, all four types of interference competition can induce disruptive selection and thus promote initial diversification. Even though foraging interference and reproductive interference are more potent in promoting initial diversification, they catalyze the formation of diverse communities with complex trophic structure only at high levels of interference intensity. By contrast, survival interference does so already at intermediate levels, while reproductive interference can only support relatively smaller communities with simpler trophic structure. Taken together, our results show how the type and intensity of interference competition jointly affect coexistence patterns in structured population models.

  10. Growth potential of Salmonella spp. and Listeria monocytogenes in nine types of ready-to-eat vegetables stored at variable temperature conditions during shelf-life.

    Sant'Ana, Anderson S; Barbosa, Matheus S; Destro, Maria Teresa; Landgraf, Mariza; Franco, Bernadette D G M

    2012-06-15

    Growth potential (δ) is defined as the difference between the population of a microorganism at the end of shelf-life of specific food and its initial population. The determination of δ of Salmonella and Listeria monocytogenes in RTE vegetables can be very useful to determine likely threats to food safety. However, little is known on the behavior of these microorganisms in several RTE vegetables. Therefore, the aim of this study was to determine the δ of both pathogens in nine different types of RTE vegetables (escarole, collard green, spinach, watercress, arugula, grated carrot, green salad, and mix for yakisoba) stored at refrigeration (7°C) and abuse temperature (15°C). The population of aerobic microorganisms and lactic acid bacteria, including those showing antimicrobial activity has been also determined. Results indicated that L. monocytogenes was able to grow (δ≥0.5 log(10)) in more storage conditions and vegetables than Salmonella. Both microorganisms were inhibited in carrots, although a more pronounced effect has been observed against L. monocytogenes. The highest δ values were obtained when the RTE vegetables were stored 15°C/6days in collard greens (δ=3.3) and arugula (δ=3.2) (L. monocytogenes) and arugula (δ=4.1) and escarole (δ=2.8) (Salmonella). In most vegetables and storage conditions studied, the counts of total aerobic microorganisms raised significantly independent of the temperature of storage (p<0.05). Counts of lactic acid bacteria were higher in vegetables partially or fully stored at abuse temperature with recovery of isolates showing antimicrobial activity. In conclusion, the results of this study show that Salmonella and L. monocytogenes may grow and reach high populations in RTE vegetables depending on storage conditions and the definition of effective intervention strategies are needed to control their growth in these products.

  11. Differences in Fine-Root Biomass of Trees and Understory Vegetation among Stand Types in Subtropical Forests.

    Fu, Xiaoli; Wang, Jianlei; Di, Yuebao; Wang, Huimin

    2015-01-01

    Variation of total fine-root biomass among types of tree stands has previously been attributed to the characteristics of the stand layers. The effects of the understory vegetation on total fine-root biomass are less well studied. We examined the variation of total fine-root biomass in subtropical tree stands at two sites of Datian and Huitong in China. The two sites have similar humid monsoon climate but different soil organic carbon. One examination compared two categories of basal areas (high vs. low basal area) in stands of single species. A second examination compared single-species and mixed stands with comparable basal areas. Low basal area did not correlate with low total fine-root biomass in the single-species stands. The increase in seedling density but decrease in stem density for the low basal area stands at Datian and the quite similar stand structures for the basal-area contrast at Huitong helped in the lack of association between basal area and total fine-root biomass at the two sites, respectively. The mixed stands also did not yield higher total fine-root biomasses. In addition to the lack of niche complementarity between tree species, the differences in stem and seedling densities and the belowground competition between the tree and non-tree species also contributed to the similarity of the total fine-root biomasses in the mixed and single-species stands. Across stand types, the more fertile site Datian yielded higher tree, non-tree and total fine-root biomasses than Huitong. However, the contribution of non-tree fine-root biomass to the total fine-root biomass was higher at Huitong (29.4%) than that at Datian (16.7%). This study suggests that the variation of total fine-root biomass across stand types not only was associated with the characteristics of trees, but also may be highly dependent on the understory layer.

  12. Differences in Fine-Root Biomass of Trees and Understory Vegetation among Stand Types in Subtropical Forests.

    Xiaoli Fu

    Full Text Available Variation of total fine-root biomass among types of tree stands has previously been attributed to the characteristics of the stand layers. The effects of the understory vegetation on total fine-root biomass are less well studied. We examined the variation of total fine-root biomass in subtropical tree stands at two sites of Datian and Huitong in China. The two sites have similar humid monsoon climate but different soil organic carbon. One examination compared two categories of basal areas (high vs. low basal area in stands of single species. A second examination compared single-species and mixed stands with comparable basal areas. Low basal area did not correlate with low total fine-root biomass in the single-species stands. The increase in seedling density but decrease in stem density for the low basal area stands at Datian and the quite similar stand structures for the basal-area contrast at Huitong helped in the lack of association between basal area and total fine-root biomass at the two sites, respectively. The mixed stands also did not yield higher total fine-root biomasses. In addition to the lack of niche complementarity between tree species, the differences in stem and seedling densities and the belowground competition between the tree and non-tree species also contributed to the similarity of the total fine-root biomasses in the mixed and single-species stands. Across stand types, the more fertile site Datian yielded higher tree, non-tree and total fine-root biomasses than Huitong. However, the contribution of non-tree fine-root biomass to the total fine-root biomass was higher at Huitong (29.4% than that at Datian (16.7%. This study suggests that the variation of total fine-root biomass across stand types not only was associated with the characteristics of trees, but also may be highly dependent on the understory layer.

  13. Ecological Inference

    King, Gary; Rosen, Ori; Tanner, Martin A.

    2004-09-01

    This collection of essays brings together a diverse group of scholars to survey the latest strategies for solving ecological inference problems in various fields. The last half-decade has witnessed an explosion of research in ecological inference--the process of trying to infer individual behavior from aggregate data. Although uncertainties and information lost in aggregation make ecological inference one of the most problematic types of research to rely on, these inferences are required in many academic fields, as well as by legislatures and the Courts in redistricting, by business in marketing research, and by governments in policy analysis.

  14. A high-performance ground-based prototype of horn-type sequential vegetable production facility for life support system in space

    Fu, Yuming; Liu, Hui; Shao, Lingzhi; Wang, Minjuan; Berkovich, Yu A.; Erokhin, A. N.; Liu, Hong

    2013-07-01

    Vegetable cultivation plays a crucial role in dietary supplements and psychosocial benefits of the crew during manned space flight. Here we developed a ground-based prototype of horn-type sequential vegetable production facility, named Horn-type Producer (HTP), which was capable of simulating the microgravity effect and the continuous cultivation of leaf-vegetables on root modules. The growth chamber of the facility had a volume of 0.12 m3, characterized by a three-stage space expansion with plant growth. The planting surface of 0.154 m2 was comprised of six ring-shaped root modules with a fibrous ion-exchange resin substrate. Root modules were fastened to a central porous tube supplying water, and moved forward with plant growth. The total illuminated crop area of 0.567 m2 was provided by a combination of red and white light emitting diodes on the internal surfaces. In tests with a 24-h photoperiod, the productivity of the HTP at 0.3 kW for lettuce achieved 254.3 g eatable biomass per week. Long-term operation of the HTP did not alter vegetable nutrition composition to any great extent. Furthermore, the efficiency of the HTP, based on the Q-criterion, was 7 × 10-4 g2 m-3 J-1. These results show that the HTP exhibited high productivity, stable quality, and good efficiency in the process of planting lettuce, indicative of an interesting design for space vegetable production.

  15. 广西植被类型及其分类系统%Types of Vegetation and Its Classified System in Guangxi

    温远光; 严理; 李治基; 李信贤; 朱宏光; 梁宏温; 和太平; 庄嘉; 罗应华; 吴庆标

    2014-01-01

    [Objective]Vegetation is the most sensitive factor of the local natural biogeography on the Earth,and play an important role in maintaining human being sustainable development and mitigating climate change.The obj ective of this paper was to introtduce systematically the types of vegetation in Guangxi and its classified system and to provide basic data for protection, research and uses of the vegetation.[Methods]Based on the classification principle,unit and sys-tem of China vegetation,the data that included both publications recording the types of Guan-gxi vegetations and authors'vegetation investigation in Guangxi since 1950 were gathered and sorted out.And then two classification systems were drawn up for natural and artificial vegeta-tions of Guangxi.[Results]The natural vegetation in Guangxi could be divided into 4 classes of vegetation type,26 groups of vegetation type,and 722 formations.The artificial vegetation in Guangxi could be divided into 5 vegetation types, 20 vegetation subtypes, and 298 formations.Among 722 formations of natural vegetation,the type numbers of forest,bamboo forest,shrub,herb and hydrovegetation account for 63%,4%,10%,6% and 17%,respectively. Among 2 9 8 formations of artificial vegetation, the type numbers of timber forest,economic frult and tree forest,urban forest vegetation,crop vegetation and artificial paludal and hydric vegetation account for 28%,20%,29%,17% and 6%,respectively.[Conclusion]Guangxi is one of the most rich regions of vegetation types in China with 1020 formations,and has an impor-tant position in the protection,research and uses of vegetation in China.%【目的】植被是地球上最为敏感的自然地理环境要素,在减缓气候变化和实现人类可持续发展中具有无法替代的作用。本文全面、系统地介绍广西植被类型及其分类系统,为植被保护、研究和利用提供基础资料。【方法】通过对已发表记载有广西植被类型以及作者近60年来对广西

  16. Spatial Vegetation Data for Tuzigoot National Monument Vegetation Mapping Project

    National Park Service, Department of the Interior — The vegetation units on this map were determined through the stereoscopic interpretation of aerial photographs supported by field sampling and ecological analysis....

  17. Spatial Vegetation Data for Colorado National Monument Vegetation Mapping Project

    National Park Service, Department of the Interior — The vegetation units on this map were determined through a series of image processing steps including unsupervised classification, ecological modeling and...

  18. The soil carbon/nitrogen ratio and moisture affect microbial community structures in alkaline permafrost-affected soils with different vegetation types on the Tibetan plateau.

    Zhang, Xinfang; Xu, Shijian; Li, Changming; Zhao, Lin; Feng, Huyuan; Yue, Guangyang; Ren, Zhengwei; Cheng, Guogdong

    2014-01-01

    In the Tibetan permafrost region, vegetation types and soil properties have been affected by permafrost degradation, but little is known about the corresponding patterns of their soil microbial communities. Thus, we analyzed the effects of vegetation types and their covariant soil properties on bacterial and fungal community structure and membership and bacterial community-level physiological patterns. Pyrosequencing and Biolog EcoPlates were used to analyze 19 permafrost-affected soil samples from four principal vegetation types: swamp meadow (SM), meadow (M), steppe (S) and desert steppe (DS). Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria dominated bacterial communities and the main fungal phyla were Ascomycota, Basidiomycota and Mucoromycotina. The ratios of Proteobacteria/Acidobacteria decreased in the order: SM>M>S>DS, whereas the Ascomycota/Basidiomycota ratios increased. The distributions of carbon and nitrogen cycling bacterial genera detected were related to soil properties. The bacterial communities in SM/M soils degraded amines/amino acids very rapidly, while polymers were degraded rapidly by S/DS communities. UniFrac analysis of bacterial communities detected differences among vegetation types. The fungal UniFrac community patterns of SM differed from the others. Redundancy analysis showed that the carbon/nitrogen ratio had the main effect on bacteria community structures and their diversity in alkaline soil, whereas soil moisture was mainly responsible for structuring fungal communities. Thus, microbial communities and their functioning are probably affected by soil environmental change in response to permafrost degradation.

  19. Soil Organic Carbon and Its Fractions Across Vegetation Types: Effects of Soil Mineral Surface Area and Microaggregates

    WU Qing-Biao; WANG Xiao-Ke; OUYANG Zhi-Yun

    2009-01-01

    Soil organic carbon (SOC) can act as a sink or source of atmospheric carbon dioxide;therefore,it is important to understand the amount and composition of SOC in terrestrial ecosystems,the spatial variation in SOC,and the underlying mechanisms that stabilize SOC.In this study,density fractionation and acid hydrolysis were used to assess the spatial variation in SOC,the heavy fraction of organic carbon (HFOC),and the resistant organic carbon (ROC) in soils of the southern Hulun Buir region,northeastern China,and to identify the major factors that contribute to this variation.The results showed that as the contents of clay and silt particles (0-50 μm) increased,both methylene blue (MB) adsorption by soil minerals and microaggregate contents increased in the 0-20 and 20-40 cm soil layers (P<0.05).Although varying with vegetation types,SOC,HFOC,and ROC contents increased significantly with the content of clay and silt particles,MB adsorption by soil minerals,and microaggregate content (P<0.05),suggesting that soil texture,the MB adsorption by soil minerals,and microaggregate abundance might be important factors influencing the spatial heterogeneity of carbon contents in soils of the southern Hulun Buir region.

  20. Effect of oil type and fatty acid composition on dynamic and steady shear rheology of vegetable oils.

    Yalcin, Hasan; Toker, Omer Said; Dogan, Mahmut

    2012-01-01

    In this study, effect of fatty acid composition on dynamic and steady shear rheology of oils was studied. For this aim, different types of vegetable oils (soybean, sunflower, olive, hazelnut, cottonseed and canola), were used. Rheological properties of oil samples were identified by rheometer (Thermo-Haake) at 25°C and fatty acid composition of oils was determined by GC (Agilent 6890). Steady shear rheological properties of oil samples were measured at shear rate range of 0.1-100 s⁻¹. Viscosity of olive, hazelnut, cottonseed, canola, soybean and sunflower was 61.2 mPa.s, 59.7 mPa.s, 57.3 mPa.s, 53.5 mPa.s, 48.7 mPa.s and 48.2 mPa.s, respectively. There was a significant difference between viscosity of oils except soybean and sunflower. As a result it was seen that there was a correlation between viscosity and monounsaturated (R=0.89), polyunsaturated (R=-0.97) fatty acid composition of oils, separately. Equation was found to predict viscosity of the oils based on mono and polyunsaturation composition of oils. In addition the dynamic rheological properties of oils were also examined. G', G'' and tan δ (G''/G') values were measured at 0.3 Pa (in viscoelastic region) and 0.1-1 Hz. As a result of multiple regression analysis another equations were found between tan δ, viscosity and polyunsaturated fatty acids.

  1. Canadian National Vegetation Classification (CNVC)

    US Fish and Wildlife Service, Department of the Interior — The mandate of the CNVC is to comprehensively classify and describe natural and semi-natural Canadian vegetation in an ecologically meaningful manner. The...

  2. Trophodynamics of current use pesticides and ecological relationships in the Bathurst region vegetation-caribou-wolf food chain of the Canadian Arctic.

    Morris, Adam D; Muir, Derek C G; Solomon, Keith R; Teixeira, Camilla; Duric, Mark; Wang, Xiaowa

    2014-09-01

    The bioaccumulation of current use pesticides (CUPs) and stable isotopes of carbon and nitrogen were investigated in vegetation-caribou-wolf food chain in the Bathurst region (Nunavut, Canada). Volumetric bioconcentration factors (BCF(v)) in vegetation were generally greatest for dacthal (10-12) ≥ endosulfan sulfate (10-11) > ß-endosulfan (>9.0-9.7) ≥ pentachloronitrobenzene (PCNB; 8.4-9.6) > α-endosulfan (8.3-9.3) > chlorpyrifos (8.0-8.7) >chlorothalonil (7.6-8.3). The BCF(v) values in vegetation were significantly correlated with the logarithm of the octanol-air partition coefficients (log K(OA)) of CUPs (r(2)  = 0.90, p = 0.0040), although dacthal was an outlier and not included in this relationship. Most biomagnification factors (BMFs) for CUPs in caribou:diet comparisons were significantly less than 1. Similarly, the majority of wolf:caribou BMFs were either significantly less than 1 or were not statistically greater than 1. Significant trophic magnification factors (TMFs) were all less than 1, indicating that these CUPs exhibit trophic dilution through this terrestrial food chain. The log K(OA) reasonably predicted bioconcentration in vegetation for most CUPs but was not correlated with BMFs or TMFs in mammals. Our results, along with those of metabolic studies, suggest that mammals actively metabolize these CUPs, limiting their biomagnification potential despite entry into the food chain through effective bioconcentration in vegetation.

  3. Comparative Analysis of Polysaccharides from Two Ecological Types of Leymus chinensis

    LI Jing-jing; BI Hong-tao; YAN Ji-hong; SUN Fang; FAN Sha-sha; CAO Gang; ZHOU Yi-fa; CHEN Xi-guang

    2012-01-01

    Leymus chinensis(Trin.) Tzvel.,widely distributed at eastern Eurasian steppe and divided into gray-green type and yellow-green type,has different stress resistance to environment.In the present study,the water-soluble polysaccharides from two ecotypes ofL.chinensis were analyzed in detail,and the differences between polysaccharides from the two ecotypes ofL.chinensis in the yield,monosaccharide composition,molecular weight and structure were clarified.The polysaccharides of L.chinensis were composed of both neutral and acidic polysaccharides.The neutral polysaccharides contained mannose,glucose,galactose,xylose and arabinose,and mainly consisted of β-1,4-Glcp,α-1,3-Galp and α-1,2-Xylp residues.The acidic polysaccharides contained mannose,rhamnose,glucuronic acid,galacturonic acid,glucose,galactose,xylose and arabinose.However,the yields,monosaccharides contents and the molecular weights of the polysaccharides from the two ecotypes of L.chinensis were different.Moreover,the resistance type(gray-green type) of L.chinensis contained a number of α-1,3-Manp and reducing end of β-Glcp residues,and much more O-methyl groups than normal type(yellow-green type) of L.chinensis.The differences of the polysaccharides of the two ecotypes ofL.chinensis might be due to the long-term environmental adaptability of plant,and the differences of the polysaccharides might influence the stress resistance of L.chinensis.

  4. Uniform persistence of multispecies ecological competition predator-pray system with Holling Ⅲ type functional response

    2008-01-01

    The main purpose of this paper is to study the persistence of the general multispecies competition predator-pray system with Holling Ⅲ type functional response.In this system,the competition among predator species and among prey species are simultaneously considered.By using the comparison theory and qualitative analysis,the sufficient conditions for uniform strong persistence are obtained.

  5. Effects of soil type and farm management on soil ecological functional genes and microbial activities

    Reeve, Jennifer [Washington State University; Schadt, Christopher Warren [ORNL; Carpenter-Boggs, Lynne [Washington State University; Kang, S. [University of Oklahoma; Zhou, Jizhong [University of Oklahoma, Norman; Reganold, John P. [Washington State University

    2010-01-01

    Relationships between soil microbial diversity and soil function are the subject of much debate. Process-level analyses have shown that microbial function varies with soil type and responds to soil management. However, such measurements cannot determine the role of community structure and diversity in soil function. The goal of this study was to investigate the role of gene frequency and diversity, measured by microarray analysis, on soil processes. The study was conducted in an agro-ecosystem characterized by contrasting management practices and soil types. Eight pairs of adjacent commercial organic and conventional strawberry fields were matched for soil type, strawberry variety, and all other environmental conditions. Soil physical, chemical and biological analyses were conducted including functional gene microarrays (FGA). Soil physical and chemical characteristics were primarily determined by soil textural type (coarse vs fine-textured), but biological and FGA measures were more influenced by management (organic vs conventional). Organically managed soils consistently showed greater functional activity as well as FGA signal intensity (SI) and diversity. Overall FGA SI and diversity were correlated to total soil microbial biomass. Functional gene group SI and/or diversity were correlated to related soil chemical and biological measures such as microbial biomass, cellulose, dehydrogenase, ammonium and sulfur. Management was the dominant determinant of soil biology as measured by microbial gene frequency and diversity, which paralleled measured microbial processes.

  6. Quantifying influences of physiographic factors on temperate dryland vegetation, Northwest China

    Du, Ziqiang; Zhang, Xiaoyu; Xu, Xiaoming; Zhang, Hong; Wu, Zhitao; Pang, Jing

    2017-01-01

    Variability in satellite measurements of terrestrial greenness in drylands is widely observed in land surface processes and global change studies. Yet the underlying causes differ and are not fully understood. Here, we used the GeogDetector model, a new spatial statistical approach, to examine the individual and combined influences of physiographic factors on dryland vegetation greenness changes, and to identify the most suitable characteristics of each principal factor for stimulating vegetation growth. Our results indicated that dryland greenness was predominantly affected by precipitation, soil type, vegetation type, and temperature, either separately or in concert. The interaction between pairs of physiographic factors enhanced the influence of any single factor and displayed significantly non-linear influences on vegetation greenness. Our results also implied that vegetation greenness could be promoted by adopting favorable ranges or types of major physiographical factors, thus beneficial for ecological conservation and restoration that aimed at mitigating environmental degradation. PMID:28067259

  7. Zinc and Other Metals Deficiencies and Risk of Type 1 Diabetes: An Ecological Study in the High Risk Sardinia Island.

    Paolo Valera

    Full Text Available Type 1 diabetes incidence presents a decreasing gradient in Europe from the Nordic countries to the Mediterranean ones. Exception to this gradient is represented by Sardinia, the second largest Mediterranean island whose population shows the highest incidence in Europe, after Finland. The genetic features of this population have created a fertile ground for the epidemic of the disease, however, as well as being strikingly high, the incidence rate has suddenly presented a continuous increase from the '50s, not explainable by accumulation of new genetic variants. Several environmental factors have been taken into account, possibly interacting with the genetic/epigenetic scenario, but there are no strong evidences to date.The present study investigated the hypothesis that geochemical elements could create permissive environmental conditions for autoimmune diabetes. An ecological analysis was performed to test possible correlations between the values of eight elements in stream sediments and type 1 diabetes incidence rate in Sardinia.Analyses revealed negative associations between elements, such as Co, Cr, Cu, Mn, Ni, Zn, and type 1 diabetes incidence.The results suggest a possible protective role of some elements against the onset of the disease.

  8. THE GENESIS OF PHOTOSYNTHESIS TYPES AS THE BASIS OF ECOLOGICAL EXPANSION OF HALOPHYTIC PLANTS

    Pyurko O.Ye.

    2011-12-01

    Full Text Available The C3, C4, and CAM photosynthesis types are considerably differed by CO2 absorption intensity, its biochemistry, saturation level, water productivity, biological productivity, and other different features, which secure the plants survival at stress and extreme conditions. The aim of current research was to discover the photosynthesis peculiarities at halophytic plants species (Salicornia europaea L., Halimione pedunculata, Artemisia santonica L., Plantago lanceolata L. by salinity at model and natural conditions, and to generalize data in historical aspect. It was constituted that S. europaea L. was characterized by C3 photosynthesis passage which was switched on CAM CO2 fixation under soil salinity conditions till 4-4,5 %, but glycophyte A.santonica was immanent C4assimilation way of aspartate type.Analysis of literature data and own research allows to find out that in majority the C3photosynthesis dependence from environmental factors described by determinate curve with matched mathematical expression. It was suggested to generalize the data by Lagrange polynomial. The obtained results proved that the pattern of photosynthesis evolution is: C3 → C4 → CAM with commute possibilities: C3 → CAM; C4 → CAM.

  9. Analysis of heavy metals in different soil types and the vegetables%不同类型土壤及蔬菜中的重金属分析

    谢娟; 田恬; 王莉平; 韩融; 陈爱侠; 何克; 王柱命; 张江华

    2015-01-01

    为了研究不同类型土壤及种植蔬菜中重金属含量,选择两块试验田,种植不同品种蔬菜,分析了土壤及蔬菜中的重金属含量. 试验结果表明:土壤深度为0~80 cm时,两种类型土壤中的重金属Pb、Cu、Zn、Cd、Cr含量随着土壤深度的增加而减小;A区土壤Pb、Cu、Zn含量比B区高;种植的小青菜、小白菜中Pb、Cd、Cr含量A区大于B区;果实类蔬菜对重金属的累积量小于叶菜类.本研究成果可为土壤污染治理提供参考,为人体健康提供依据.%In order to study the content of heavy metals in different soil types and the vegetables planted,this pa-per chooses two plots to plant different varieties of vegetables,and analyzes the heavy metals content in the soil and vegetables.The results show that within the scope of 0 cm to 80 cm,the concentration of heavy metals Pb,Cu,Zn,Cd, Cr in two types of soil decreases with the soil depth.The content of heavy metals Pb,Cu,Zn in A area is higher than B area.The content of heavy metals Pb,Cd,Cr in small brassinca chinensis and small cabbages planted in A area is more than that in B area.Heavy metals accumulation amount in fruit vegetables is less than leaf vegetables.This study pro-vides reference for the soil pollution control and the basis for human health management.

  10. 搓动式沉水植物脱盐机脱盐效果的试验研究%Experimental Study on Desalting Efficacy of Rubbing Type Submerged Vegetation Desalting Machine

    岳海军; 尚士友; 马清艳

    2014-01-01

    In the ecological management and resources development of Lake Wuliangsuhai , harvesting submerged vegeta-tion by mechanization method can decrease the accumulation of internal nutrient salts ; meliorate the water environment and transfer nutrient salts of nitrogen and phosphorus to achieve the purpose of eutrophication management and resources development .Design of rubbing type submerged vegetation desalting machine can decrease the amount of nutrient salts on the submerged plants after harvesting , improve the dainty of submerged vegetation feedstuff .Desalting submerged vegeta-tion shows that removal effect for about 9%-22 %moisture , 720 r/min rated rotation speed and 16 mm size of vibration sieve pore is the best and maximum removal rate reaches to 85 .45%, its desalting efficacy is better than beater pulveriz-er.Grey system theory model was set up to estimate desalting rate , average error is -1.66%, which lays theoretical foundation for its technology parameter optimization .%在乌梁素海的生态治理和资源开发中,以机械化方式收割沉水植物能够削减湖泊内各种营养盐的积累,转移各种氮磷营养盐,改善水质环境,实现湖泊富营养化治理和资源开发兼顾的目的。搓动式沉水植物脱盐机的研究设计,能够减少收割后沉水植物的含盐量,提高其作为沉水植物饲料的适口性。对晒干后的沉水植物进行脱盐试验表明:在含水率9%~22%,电动机额定转速720r/min,振动筛孔16mm 时,最大去除率达85.45%,较锤片式粉碎机去除效果好。利用灰色系统理论建立数学模型,预测不同工艺参数时的沉水植物饲料脱盐率,其平均误差为-1.66%,可为其工艺参数优化提供理论依据。

  11. Relationship between tourism development and vegetated landscapes in Luya Mountain Nature Reserve, Shanxi, China.

    Cheng, Zhan-Hong; Zhang, Jin-Tun

    2005-09-01

    The relationship between tourism development and vegetated landscapes is analyzed for the Luya Mountain Nature Reserve (LMNR), Shanxi, China, in this study. Indices such as Sensitive Level (SL), Landscape Importance Value (LIV), information index of biodiversity (H'), Shade-tolerant Species Proportion (SSP), and Tourism Influencing Index (TII) are used to characterize vegetated landscapes, the impact of tourism, and their relationship. Their relationship is studied by Two-Way Indicator Species Analysis (TWINSPAN) and Detrended Correspondence Analysis (DCA). TWINSPAN gives correct and rapid partition to the classification, and DCA ordination shows the changing tendency of all vegetation types based on tourism development. These results reflect the ecological relationship between tourism development and vegetated landscapes. In Luya Mountain Nature Reserve, most plant communities are in good or medium condition, which shows that these vegetated landscapes can support more tourism. However, the occurrence of the bad condition shows that there is a severe contradiction between tourism development and vegetated landscapes.

  12. Observations on the distribution and ecology of Clostridium botulinum type E in Alaska.

    Miller, L G

    1975-06-01

    Environmental samples collected along the coastline and from the interior of Alaska were examined for the presence of Clostridium botulinum. Clostridium botulinum type E was detected in soils from 5 of 12 beaches; in 7 of 115 non-coastal soil samples; in sediments from six of eight locales; in gills of salmon from two fishing areas; and in the feces of 1 of 44 colonic samples from marine mammals. The basic biochemical characteristics of the isolates were determined. Tube tests for demonstrating gelatin liquefaction proved insensitive with these strains, whereas a plate test detected gelatinase in all isolates. The presence of multiple nidi and the continual discharge of organic materials into the environment may contribute to the perpetuation of botulinum spores by which foods prepared form marine animals become contaminated. An emphasis should be placed upon the need for measures to reduce environmental contamination, to reduce contamination during food preparation, and to alert continually the population of the hazard wherever botulism is endemic.

  13. Vegetables and PUFA-rich plant oil reduce DNA strand breaks in individuals with type 2 diabetes

    Müllner, Elisabeth; Brath, Helmut; Pleifer, Simone;

    2013-01-01

    (Comet Assay), urinary excretion of 8-oxo-7-hydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo) and glycated hemoglobin (HbA1c) were measured at baseline, after 4, 8 (end of intervention), and 16 weeks. The intervention with vegetables and PUFA-rich oil led to a significant...

  14. Measurement of ecological capital of Chinese terrestrial ecosystem based on remote sensing

    PAN; Yaozhong; SHI; Peijun; ZHU; Wenquan; GU; Xiaohe; FAN

    2005-01-01

    The biosphere of the Earth is essential to human survival and development. The services of ecosystems are critical to the functioning of the Earth's life-support system. They contribute to human welfare both directly and indirectly. Ecological capital refers to the sum of the direct biological resources value and the indirect ecosystem services value. It is necessary to estimate the ecological capital in order to bring it to the society and market economic system, and draw the social attention to ecological environment constructions. An estimation model for ecological capital based on remote sensing is presented in this paper. The parameters in the model are quantitatively measured using NOAA/AVHRR and other ancillary data, including the land cover types, the vegetation coverage, and the vegetation net primary productivity (NPP) of terrestrial ecosystem. Based on the economic parameters in previously published studies and a few original calculations, the annual ecological capital of the entire terrestrial ecosystem of China is quantitatively estimated at 6.44 trillion (1012) yuan (RMB), and the spatial distribution of the ecological capital is also analyzed. Traditional ecological methods to ecological capital measurement are based on homogeneous plot scales, and the regional scaling is a key problem in their applications. As the proposed remote sensing approach, it provides a new method to ecological capital measurement completely based on observation data. It can not only overcome the regional scaling problem easily, but also allows the ecological capital to be estimated objectively and spatial-explicitly.

  15. Projected impacts of 21st century climate change on the distribution of potential habitat for vegetation, forest types and major conifer species across Russia.

    Tchebakova, Nadezda; Parfenova, Elena; Cantin, Alan; Shvetsov, Eugene; Soja, Amber; Conard, Susane

    2013-04-01

    Global simulations have demonstrated the potential for profound effects of GCM-projected climate change on the distribution of terrestrial ecosystems and individual species at all hierarchical levels. We modeled progressions of potential vegetation cover, forest cover and forest types in Russia in the warming climate during the 21st century. We used large-scale bioclimatic models to predict zonal vegetation (RuBCliM), and forest cover (ForCliM) and forest types. A forest type was defined as a combination of a dominant tree conifer and a ground layer. Distributions of vegetation zones (zonobiomes), conifer species and forest types were simulated based on three bioclimatic indices (1) growing degree-days above 5oC ; (2) negative degree-days below 0oC; and (3) an annual moisture index (ratio of growing degree days to annual precipitation). Additionally, the presence/absence of continuous permafrost, identified by active layer depth of 2 m, was explicitly included in the models as limiting the forests and tree species distribution in Siberia. All simulations to predict vegetation change across Russia were run by coupling our bioclimatic models with bioclimatic indices and the permafrost distribution for the baseline period 1971-2000 and for the future decades of 2011-2020, 2041-2050 and 2091-2100. To provide a range of warming we used three global climate models (CGCM3.1, HadCM3 and IPSLCM4) and three climate change scenarios (A1B, A2 and B1). The CGCM model and the B1 scenario projected the smallest temperature increases, and the IPSL model and the A2 scenario projected the greatest temperature increases. We compared the modeled vegetation and the modeled tree species distributions in the contemporary climate to actual vegetation and forest maps using Kappa (K) statistics. RuBioCliM models of Russian zonal vegetation were fairly accurate (K= 0.40). Contemporary major conifer species (Pinus sibirica, Pinus sylvestris, Larix spp., Abies sibirica and Picea obovata

  16. Physiological and ecological studies of the vegetation on ore deposits. I. Zinc flora and indicator plants on the 2nd Yunwha mine. [Sedum sp. ; Dianthus sinensis

    Chang, N.K.; Chang, S.M.

    1977-01-01

    During the period of 1975-76, a survey was carried out to find out zinc indicators in the natural vegetation in Korea. The symptoms of chlorosis were observed in flowering plants in the areas of zinc outcrop of Wolgok-A, Seokgok-9, and Sowolgok. Although 28 species were found to be chlorotic, the total quantity of chlorotic foliage observed was small. Reasons for chlorosis in the areas of zinc ore deposits is considered as effects of zinc, lead, copper and calcium ions. Sedum sp. and Dianthus sinensis were confined to soil containing more than exchangeable zinc of 30 ppm and to accumulation in the plants contained at least 1,300-14,000 ppm of zinc. Therefore, Sedum sp. and Dianthus sinensis might be used as zinc indicators in Korea. 12 references, 1 figure, 5 tables.

  17. [Feeding habits and trophic ecology of the fish Lutjanus griseus (Pisces: Lutjanidae) associated with submerged vegetation in Laguna de Términos, Campeche, Mexico].

    Guevara, Emma; Alvarez, Hernán; Mascaró, Maite; Rosas, Carlos; Sánchez, Alberto

    2007-01-01

    In Campeche, Mexico, the Laguna de Términos has Thalassia testudinum beds inhabited by the grey snapper, Lutjanus griseus (Linnaeus 1758). Along one year, we collected 994 individuals and 672 had food in their stomachs; we recorded number, weight, and frequency oftrophic groups, and the index of relative importance. Dominant food components were Farfantepenaeus duorarum and Palemonetes octaviae, Eucinostomus gula (Cuvier 1830) and Libinia dubia. Salinity and temperature were related to the number of individuals collected and with greater fish consumption by large L. griseus. The trophic niche breadth index was calculated for six size-classes of fish. The smallest and the largest fish had the lowest index values, whereas medium-size snappers had higher values. This snapper has a preference for habitats with submerged vegetation. The percentage of fish with food in their stomachs was higher during dark hours, providing evidence of the nocturnal habits of this fish.

  18. Balkan Vegetation Database

    Vassilev, Kiril; Pedashenko, Hristo; Alexandrova, Alexandra; Tashev, Alexandar; Ganeva, Anna; Gavrilova, Anna; Gradevska, Asya; Assenov, Assen; Vitkova, Antonina; Grigorov, Borislav; Gussev, Chavdar; Filipova, Eva; Aneva, Ina; Knollová, Ilona; Nikolov, Ivaylo; Georgiev, Georgi; Gogushev, Georgi; Tinchev, Georgi; Pachedjieva, Kalina; Koev, Koycho; Lyubenova, Mariyana; Dimitrov, Marius; Apostolova-Stoyanova, Nadezhda; Velev, Nikolay; Zhelev, Petar; Glogov, Plamen; Natcheva, Rayna; Tzonev, Rossen; Boch, Steffen; Hennekens, Stephan M.; Georgiev, Stoyan; Stoyanov, Stoyan; Karakiev, Todor; Kalníková, Veronika; Shivarov, Veselin; Russakova, Veska; Vulchev, Vladimir

    2016-01-01

    The Balkan Vegetation Database (BVD; GIVD ID: EU-00-019; http://www.givd.info/ID/EU-00- 019) is a regional database that consists of phytosociological relevés from different vegetation types from six countries on the Balkan Peninsula (Albania, Bosnia and Herzegovina, Bulgaria, Kosovo, Montenegro

  19. Variation in trait trade-offs allows differentiation among predefined plant functional types: implications for predictive ecology.

    Verheijen, Lieneke M; Aerts, Rien; Bönisch, Gerhard; Kattge, Jens; Van Bodegom, Peter M

    2016-01-01

    Plant functional types (PFTs) aggregate the variety of plant species into a small number of functionally different classes. We examined to what extent plant traits, which reflect species' functional adaptations, can capture functional differences between predefined PFTs and which traits optimally describe these differences. We applied Gaussian kernel density estimation to determine probability density functions for individual PFTs in an n-dimensional trait space and compared predicted PFTs with observed PFTs. All possible combinations of 1-6 traits from a database with 18 different traits (total of 18 287 species) were tested. A variety of trait sets had approximately similar performance, and 4-5 traits were sufficient to classify up to 85% of the species into PFTs correctly, whereas this was 80% for a bioclimatically defined tree PFT classification. Well-performing trait sets included combinations of correlated traits that are considered functionally redundant within a single plant strategy. This analysis quantitatively demonstrates how structural differences between PFTs are reflected in functional differences described by particular traits. Differentiation between PFTs is possible despite large overlap in plant strategies and traits, showing that PFTs are differently positioned in multidimensional trait space. This study therefore provides the foundation for important applications for predictive ecology.

  20. Building the United States National Vegetation Classification

    Franklin, S.B.; Faber-Langendoen, D.; Jennings, M.; Keeler-Wolf, T.; Loucks, O.; Peet, R.; Roberts, D.; McKerrow, A.

    2012-01-01

    The Federal Geographic Data Committee (FGDC) Vegetation Subcommittee, the Ecological Society of America Panel on Vegetation Classification, and NatureServe have worked together to develop the United States National Vegetation Classification (USNVC). The current standard was accepted in 2008 and fosters consistency across Federal agencies and non-federal partners for the description of each vegetation concept and its hierarchical classification. The USNVC is structured as a dynamic standard, where changes to types at any level may be proposed at any time as new information comes in. But, because much information already exists from previous work, the NVC partners first established methods for screening existing types to determine their acceptability with respect to the 2008 standard. Current efforts include a screening process to assign confidence to Association and Group level descriptions, and a review of the upper three levels of the classification. For the upper levels especially, the expectation is that the review process includes international scientists. Immediate future efforts include the review of remaining levels and the development of a proposal review process.

  1. Agricultural non-point nitrogen pollution control function of different vegetation types in riparian wetlands: A case study in the Yellow River wetland in China

    ZHAO Tongqian; XU Huashan; HE Yuxiao; TAI Chao; MENG Hongqi; ZENG Fanfu; XING Menglin

    2009-01-01

    Riparian wetland is the major transition zone of matter, energy and information transfer between aquatic and terrestrial ecosystems and has important functions of water purification and non-point pollution control. Using the field experiment method and an isotope tracing technique, the agricultural non-point nitrogen pollution control function of different vegetation types in riparian wetland was studied in the Kouma Section of the Yellow River. The results showed that the retention of agricultural non-point nitrogen pollution by riparian wetland soil occurs mainly in top 0-10 cm layer. The amount of nitrogen retained by surface soils associated with three types of vegetation are 0.045 mg/g for Phragmites communis Trin Lima, 0.036 mg/g for Scirpus triqueter Liun, and 0.032 mg/g for Typha angustifolia Linn, which account for 59.21%, 56.25%, and 56.14% of the total nitrogen interception, respectively. Exogenous nitrogen in 0-10 cm soil layer changes more quickly than in other layers. One month after adding K15NO3 to the tested vegetation, nitrogen content was 77.78% for P. Communis Trin, 68.75% for T. Angustifolia, and 8.33% for S. Triqueter in the surface soil. After three months, nitrogen content was 93.33% for P. Communis Trin, 72.22% for S. Triqueter, and 37.50% for T. Angustifolia. There are large differences among vegetation communities respecting to purification of agricultural non-point nitrogen pollution. The nitrogen uptake amount decreases in the sequence: new shoots of P. Communis Trin (9.731 mg/g)>old P. Communis Trin (4.939 mg/g)>S. Triqueter (0.620 mg/g)>T. Angustifolia (0.186 mg/g). Observations indicated that the presence of riparian wetlands as buffers on and adjacent to stream banks could be recommended to control agricultural non-point pollution.

  2. Ecology of Listeria spp. in a fish farm and molecular typing of Listeria monocytogenes from fish farming and processing companies.

    Miettinen, Hanna; Wirtanen, Gun

    2006-11-01

    This study focused on the ecology of Listeria monocytogenes in a fish farm by following the changes in its occurrence in different types of samples for a three year period. In addition, L. monocytogenes isolates from different seafood industry areas were compared with pulsed field gel electrophoresis (PFGE) typing to discover possible associations between primary production, further processing and final products. Weather conditions were found to have a strong influence on the probability of finding Listeria spp. in a fish farm environment. The number of samples contaminated with Listeria spp. was typically bigger after rainy periods. Brook and river waters as well as other runoff waters seemed to be the main contamination source at the farm studied. The farmed fish originally found to carry L. monocytogenes become gradually Listeria free. The time needed for the purification of the fish was several months. The sea bottom soil samples were the ones that preserved the L. monocytogenes contamination the longest time. It can be stated that the fish and fish farm equipment studied did not spread listeria contamination. On the contrary, they were found to suffer from listeria contamination coming from outside sources like the brook water. There was a wide range of different L. monocytogenes PFGE-pulsotypes (30) found at 15 Finnish fish farms and fish processing factories. L. monocytogenes isolates from the final products often belonged to the same pulsotypes as did the isolates from the processing environment as well as from the raw fish. This suggests that, in addition to the fish processing factory environment, the fish raw materials are important sources of L. monocytogenes contamination in final products.

  3. Comparison of different cutaneous carotenoid sensors and influence of age, skin type, and kinetic changes subsequent to intake of a vegetable extract

    Meinke, Martina C.; Schanzer, Sabine; Lohan, Silke B.; Shchatsinin, Ihar; Darvin, Maxim E.; Vollert, Henning; Magnussen, Björn; Köcher, Wolfang; Helfmann, Jürgen; Lademann, Jürgen

    2016-10-01

    In the last decade, cutaneous carotenoid measurements have become increasingly popular, as carotenoids were found to be a biomarker of nutrition rich in fruits and vegetables, permitting monitoring of the influence of various stress factors. For such measurements, in addition to the specific and selective resonance Raman spectroscopy (RRS), newly developed low expensive small and mobile sensors that are based on spatially resolved reflectance spectroscopy (SRRS) are used for cutaneous carotenoid measurements. Human volunteers of different age exhibiting skin types I to III were investigated using RRS and two SRRS-based sensors to determine the influence of these parameters on the measuring results. In two studies on volunteers of either the same age or skin type, however, the respective other parameter being varied and no significant influences of age or skin type could be detected. Furthermore, the kinetic changes resulting from the intake and discontinued intake of a vegetable extract rich in carotenoids showed a good correlation among the three sensors and with the detected blood carotenoids. This illustrates that the SRRS-based sensors and RRS device provide reliable cutaneous carotenoid values independent of age and skin types I to III of the volunteers.

  4. [Ecology and ecologies].

    Valera, Luca

    2011-01-01

    Ecology (from the Greek words οιχοσ, "house" and λογια "study of") is the science of the "house", since it studies the environments where we live. There are three main ways of thinking about Ecology: Ecology as the study of interactions (between humans and the environment, between humans and living beings, between all living beings, etc.), Ecology as the statistical study of interactions, Ecology as a faith, or rather as a science that requires a metaphysical view. The history of Ecology shows us how this view was released by the label of "folk sense" to gain the epistemological status of science, a science that strives to be interdisciplinary. So, the aim of Ecology is to study, through a scientific methodology, the whole natural world, answering to very different questions, that arise from several fields (Economics, Biology, Sociology, Philosophy, etc.). The plurality of issues that Ecology has to face led, during the Twentieth-century, to branch off in several different "ecologies". As a result, each one of these new approaches chose as its own field a more limited and specific portion of reality.

  5. Vegetation Growth Monitoring Under Coal Exploitation Stress by Remote Sensing in the Bulianta Coal Mining Area

    2007-01-01

    Coal exploitation inevitably damages the natural ecological environment through large scale underground exploitation which exhausts the surrounding areas and is the cause of surface subsidence and cracks.These types of damage seriously lower the underground water table.Deterioration of the environment has certainly an impact on and limits growth of vegetation, which is a very important indicator of a healthy ecological system.Dynamically monitoring vegetation growth under coal exploitation stress by remote sensing technology provides advantages such as large scale coverage, high accuracy and abundant information.A scatter plot was built by a TM (Thematic Mapper) infrared and red bands.A detailed analysis of the distributional characteristics of vegetation pixels has been carried out.Results show that vegetation pixels are affected by soil background pixels, while the distribution of soil pixels presents a linear pattern.Soil line equations were obtained mainly by linear regression.A new band, reflecting vegetation growth, has been obtained based on the elimination of the soil background.A grading of vegetation images was extracted by means of a density slice method.Our analysis indicates that before the exploitation of the Bulianta coal mining area, vegetation growth had gradually reduced; especially intermediate growth vegetation had been transformed into low vegetation.It may have been caused by the deterioration of the brittle environment in the western part of the mining area.All the same, after the start of coal production, vegetation growth has gradually improved, probably due to large scale aerial seeding.Remote sensing interpretation results proved to be consistent with the actual situation on the ground.From our research results we can not conclude that coal exploitation stress has no impact on the growth of vegetation.More detailed research on vegetation growth needs to be analyzed.

  6. La ecología espacial como punto de encuentro entre la ecología animal y vegetal. Modelos espacialmente explícitos de dispersión endozoócora

    L. Santamaría

    2006-01-01

    Full Text Available Modelos espacialmente explícitos de dispersión endozoócora. En este artículo, utilizamos los sistemas de dispersión de semillas como ejemplo para exponer la importancia de la ecología espacial en las interacciones planta-animal. Estos sistemas han recibido la atención prioritaria de los ecólogos vegetales, lo que ha conllevado tanto una simplificación excesiva del papel que juegan el comportamiento y fisiología de los animales dispersantes. Además, el enfoque casi exclusivo en los "kernel de dispersión" unidimensionales involucra asunciones que son generalmente violadas en los sistemas de estudio, como la isometría del kernel dispersivo o la ausencia de heterogeneidad espacial en dicho kernel. La mayoría de estas limitaciones pueden corregirse mediante la inclusión explícita del componente espacial, pasando de modelos de dispersión unidimensionales a modelos bi- o tri-dimensionales. Este enfoque se ilustra con dos ejemplos: la dispersión de semillas de Ephedra fragilis por la lagartija balear, Podarcis lilfordii, y el papel del elefante asiático, Oliphas maximus, en la dispersión de especies nativas e invasoras del bosque tropical seco de Sri Lanka.

  7. Vegetation type and the presence of ash as factors in the evolution of soil water repellency after a forest fire

    P. Jiménez-Pinilla

    2013-05-01

    Full Text Available After wildfires, burning may induce the occurrence of soil water repellency. Soil water repellency may vary in space and time in function of vegetation, the presence of ash and soil moisture. This study analyzes the evolution of fire-induced soil water repellency in function of these factors, and proposes measures to promote the restoration of fire-affected soils. Burnt and unburnt (control soil plots under pine and shrub from a recently burned area (Gorga, Alicante, SE Spain were established. Three treatments were applied: in some of the plots, the original ash layer was kept on the ground; in a second group, the ash layer was removed for simulating the effects of erosion; finally, in a third group, percolating irrigation was conducted to simulate a possible good input of water into the soil profile after burning, that could occur if the first rains were with high quantity but low intensity. During the dry season, soil moisture content was significantly lower in burned plots due to fire-induced water repellency and reduced vegetation cover. During the wet season, soil moisture decreased in the control unburnt plots due to direct evaporation of water intercepted by vegetation and consumption by roots. Fire increased soil water repellency only in plots under pine. Water repellency decreased during the wet season, disappearing in January and reappearing after declining rainfalls. This baseline recovery of soil water repellency was lower where ash removal was simulated. In unburned plots, seasonal fluctuations were less important. In general, ash removal promotes a rapid reduction of water repellency, since it can induce washing of hydrophobic compounds. Irrigation performed immediately after the fire also contributed to decreased water repellency.

  8. Description and validation of an automated methodology for mapping mineralogy, vegetation, and hydrothermal alteration type from ASTER satellite imagery with examples from the San Juan Mountains, Colorado

    Rockwell, Barnaby W.

    2012-01-01

    The efficacy of airborne spectroscopic, or "hyperspectral," remote sensing for geoenvironmental watershed evaluations and deposit-scale mapping of exposed mineral deposits has been demonstrated. However, the acquisition, processing, and analysis of such airborne data at regional and national scales can be time and cost prohibitive. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor carried by the NASA Earth Observing System Terra satellite was designed for mineral mapping and the acquired data can be efficiently used to generate uniform mineral maps over very large areas. Multispectral remote sensing data acquired by the ASTER sensor were analyzed to identify and map minerals, mineral groups, hydrothermal alteration types, and vegetation groups in the western San Juan Mountains, Colorado, including the Silverton and Lake City calderas. This mapping was performed in support of multidisciplinary studies involving the predictive modeling of surface water geochemistry at watershed and regional scales. Detailed maps of minerals, vegetation groups, and water were produced from an ASTER scene using spectroscopic, expert system-based analysis techniques which have been previously described. New methodologies are presented for the modeling of hydrothermal alteration type based on the Boolean combination of the detailed mineral maps, and for the entirely automated mapping of alteration types, mineral groups, and green vegetation. Results of these methodologies are compared with the more detailed maps and with previously published mineral mapping results derived from analysis of high-resolution spectroscopic data acquired by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) sensor. Such comparisons are also presented for other mineralized and (or) altered areas including the Goldfield and Cuprite mining districts, Nevada and the central Marysvale volcanic field, Wah Wah Mountains, and San Francisco Mountains, Utah. The automated

  9. Vegetation cover and relationships of habitat-type with elevation on the Mississippi-Alabama Barrier Islands in the initial six years after Hurricane Katrina

    Funderburk, W.; Carter, G. A.; Anderson, C. P.; Jeter, G. W., Jr.; Otvos, E. G.; Lucas, K. L.; Hopper, N. L.

    2015-12-01

    Quantifying change in vegetation and geomorphic features which occur during and after storm impact is necessary toward understanding barrier island habitat resiliency under continued climate warming and sea level rise. In August, 2005, the Mississippi-Alabama barrier islands, including, from west-to-east, Cat, West Ship, East Ship, Horn, Petit Bois and Dauphin islands, were completely inundated by the tidal surge of Hurricane Katrina. Overwash, scouring, burial under sand, and mechanical damage combined with saltwater flooding and post-storm drought resulted in immediate and long-term vegetation loss. Remotely-sensed data acquired before (2004-2005) and after (2005-2011) Katrina were compared via image classification to determine immediate storm impacts and assess natural re-growth of land area and vegetation. By 2008, merely three years after the storm, total land area of Cat, West Ship, East Ship, Horn, Petit Bois and West Dauphin had recovered to 92, 90, 33, 99, 93 and 91 percent, and total vegetated land area to 85, 101, 85, 94, 83 and 102 percent of pre-Katrina values, respectively. Habitat-type maps developed from field survey, SPOT-5 and radar data were compared with LIDAR-derived elevation models to assess 2010 habitat-type distribution with respect to ground elevation. Although median MSL elevations associated with habitat classes ranged only from 0.5 m to 1.4 m, habitat-type changed distinctively with decimeter-scale changes in elevation. Low marsh, high marsh, estuarine shrubland, slash pine woodland, beach dune, bare sand and beach dune herbland were associated with median elevations of 0.5, 0.9, 1.0, 1.1, 1.2, 1.3 and 1.4 m ± 0.1 m, respectively. The anticipated increases in sea level and tropical storm energy under a continually warming climate will likely inhibit the reformation of higher-elevation habitat-types, such as shrublands and woodlands, in the 21st century.

  10. Rational groundwater table indicated by the eco-physiological parameters of the vegetation: A case study of ecological restoration in the lower reaches of the Tarim River

    CHEN Yaning; WANG Qiang; LI Weihong; RUAN Xiao; CHEN Yapeng; ZHANG Lihua

    2006-01-01

    The eco-physiological response and adaptation of Populus euphratica Oliv and Tamarix ramosissima Ldb during water release period were investigated. Nine typical areas and forty-five transects were selected along the lower reaches of Tarim River. The groundwater table as well as plant performance and the contents of proline, soluble sugars,and plant endogenous hormone (ABA, CTK) in leaves were monitored and analyzed. The groundwater table was raised in different areas and transects by water release program. The physiological stress to P. euphratica and T. ramosissima had been reduced after water release. Our results suggested that the groundwater table in the studied region remained at-3.15 to -4.12 m, the proline content from 9.28 to 11.06 (mmol/L), the soluble sugar content from 224.71 to 252.16 (mmol/L), the ABA content from 3.59 to 5.01 (ng/g FW), and the CK content from 4.01 to 4.56 (ng/g FW), for the optimum growth and restoration of P. euphratica indicated by the plant performance parameters and the efficiency of water application was the highest. The groundwater table in the studied region remained at -2.16 to -3.38 m, the proline content from 12.15 to 14.17 (mmol/L), the soluble sugar content from 154.71 to 183.16 (mmol/L), the ABA content from 2.78 to 4.86 (ng/g FW), and the CK content from 3.78 to 4.22 (ng/g FW), for the optimum growth and restoration of T. ramosissima indicated by the plant performance parameters and the efficiency of water application was the highest. The rational groundwater table for the restoration of vegetation in the studied region was at -3.15 to -3.38 m.

  11. Re-assignment of the Affinities of the Fossil Pollen Type Tricolpites trioblatus Mildenhall and Pocknall to Wilsonia (Convolvulaceae) and a reassessment of the ecological interpretations.

    Martin

    2000-09-01

    Tricolpites trioblatus Mildenhall and Pocknall was described from Upper Miocene-Pliocene sediments of New Zealand and attributed to the Hebe complex (Scrophulariaceae), which is common in the New Zealand vegetation, especially in montane and subalpine habitats. Pollen in Miocene-Pliocene sediments in central Australia is identified with T. trioblatus, and the depositional situations included shallow lakes, with fresh or brackish waters, sometimes becoming saline. The affinities of T. trioblatus are re-examined in the light of these disparate environments in Australia and New Zealand. It has been found that all the fossil grains examined are more comparable to pollen of Wilsonia, and perhaps Cressa (Convolvulaceae), than to those of the Hebe complex. Wilsonia and Cressa are found in salt marshes, hence affinities with them are ecologically more credible for central Australia. T. trioblatus is found in late Eocene sediments deposited under episodic marine transgressions; an environment likely to stimulate the evolution of new species tolerant to saline conditions.

  12. Study on Climatic Variation and Its Effect on Vegetable Type Soybean Genotypes at Khumaltar, Lalitpur in the Last Ten Years

    Santosh Raj Tripathi

    2015-03-01

    Full Text Available Soybean (Glycine max L. Merril is widely grown in the mid hills as intercrop with maize or in paddy bunds, while it is gaining popularity as sole crop in terai and inner terai. Mean temperature at Khumaltar during soybean growing period was mostly fluctuating; but we observed an increasing trend in temperature. Amount of rainfall was not changed dramatically but number of rainy days was decreased during study period. Rainfall during germination time increase soil moisture which also increase germination and found higher early stand. Days from sowing to 50% flowering and 90% maturity were short in the case of higher minimum temperature and low rainfall. Among the genotypes, AGS-377, AGS-378, AGS-379 and Tarkari Bhattmas-1 were more sensitive. However, seed yield decreased in the case of higher temperatures and low rainfall. Cool night temperatures and high moisture increased disease incidence in soybean which, eventually reduced yield. In last three years, plant suffered from moisture stress during early vegetative stage and high moisture during late vegetative stage which reduced seed yield and seed weight. In conclusion, we found that genotypes like AGS- 360, Sathiya and Tarkari Bhatmas-1 are very sensitive to climatic variation.

  13. Seasonal Dynamics of Soil Labile Organic Carbon and Enzyme Activities in Relation to Vegetation Types in Hangzhou Bay Tidal Flat Wetland.

    Shao, Xuexin; Yang, Wenying; Wu, Ming

    2015-01-01

    Soil labile organic carbon and soil enzymes play important roles in the carbon cycle of coastal wetlands that have high organic carbon accumulation rates. Soils under three vegetations (Phragmites australis, Spartina alterniflora, and Scirpusm mariqueter) as well as bare mudflat in Hangzhou Bay wetland of China were collected seasonally. Seasonal dynamics and correlations of soil labile organic carbon fractions and soil enzyme activities were analyzed. The results showed that there were significant differences among vegetation types in the contents of soil organic carbon (SOC) and dissolved organic carbon (DOC), excepting for that of microbial biomass carbon (MBC). The P. australis soil was with the highest content of both SOC (7.86 g kg-1) and DOC (306 mg kg-1), while the S. mariqueter soil was with the lowest content of SOC (6.83 g kg-1), and the bare mudflat was with the lowest content of DOC (270 mg kg-1). Soil enzyme activities were significantly different among vegetation types except for urease. The P. australis had the highest annual average activity of alkaline phosphomonoesterase (21.4 mg kg-1 h-1), and the S. alterniflora had the highest annual average activities of β-glycosidase (4.10 mg kg-1 h-1) and invertase (9.81 mg g-1 24h-1); however, the bare mudflat had the lowest activities of alkaline phosphomonoesterase (16.2 mg kg-1 h-1), β-glycosidase (2.87 mg kg-1 h-1), and invertase (8.02 mg g-1 24h-1). Analysis also showed that the soil labile organic carbon fractions and soil enzyme activities had distinct seasonal dynamics. In addition, the soil MBC content was significantly correlated with the activities of urease and β-glucosidase. The DOC content was significantly correlated with the activities of urease, alkaline phosphomonoesterase, and invertase. The results indicated that vegetation type is an important factor influencing the spatial-temporal variation of soil enzyme activities and labile organic carbon in coastal wetlands.

  14. Analyzing nonlinear variations in terrestrial vegetation in China during 1982-2012.

    Liu, Yanxu; Liu, Xianfeng; Hu, Yi'na; Li, Shuangshuang; Peng, Jian; Wang, Yanglin

    2015-11-01

    Quantifying the long-term trends of changes in terrestrial vegetation on a large scale is an effective method for detecting the effects of global environmental change. In view of the trend towards overall restoration and local degradation of terrestrial vegetation in China, it is necessary to pay attention to the spatial processes of vegetative restoration or degradation, as well as to clarify the temporal and spatial characteristics of vegetative growth in greater geographical detail. However, traditional linear regression analysis has some drawbacks when describing ecological processes. Combining nonparametric linear regression analysis with high-order nonlinear fitting, the temporal and spatial characteristics of terrestrial vegetative growth in China during 1982-2012 were detected using the third generation of Global Inventory Modeling and Mapping Studies (GIMMS3g) dataset. The results showed that high-order curves could be effective. The region joining Ordos City and Shaanxi Gansu Ningxia on the Loess Plateau may have experienced restoration-degradation-restoration processes of vegetative growth. In the Daloushan Mountains, degradation-restoration processes of vegetative growth may have occurred, and the occurrence of several hidden vegetative growth processes was located in different regions of eastern China. Changes in cultivated vegetation were inconsistent with changes in other vegetation types. In southern China and some high-altitude areas, temperature was the primary driver of vegetative growth on an interannual scale, while in the north, the effect of rainfall was more significant. Nevertheless, the influence of climate on vegetation activity in large urban areas was weak. The trend types of degradation-restoration processes in several regions were inconsistent with the implements of regional land development and protection strategy. Thus, the role of human activity cannot be ignored. In future studies, it will be still necessary to quantify the

  15. Improvement of boreal vegetation modelling and climate interactions through the introduction of new bryophyte and artic-shrub plant functional types in a land surface model.

    Druel, Arsène; Krinner, Gerhard; Peylin, Philippe; Ciais, Philippe; Viovy, Nicolas; Peregon, Anna

    2016-04-01

    Boreal and tundra vegetation, which represents 22% of the global land area, has had a significant impact on climate through changes of albedo, snow cover, soil thermal dynamics, etc. However, it is frequently poorly represented in earth system models used for climate predictions. We improved the description of high-latitude vegetation and its interactions with the environment in the ORCHIDEE land surface model by creating new plant functional types with specific biogeochemical and biophysical properties: boreal shrubs, bryophytes (mosses and lichens) and boreal C3 grasses. The introduction of shrub specificities allows for an intermediate stratum between trees and grasses, with a new carbon allometry within the plant, inducing new interactions between wooden species and their environment, especially the complex snow-shrubs interaction. Similarly, the introduction of non-vascular plants (i.e. bryophytes) involves numerous changes both in physical and biological processes, such as the response of photosynthesis to surface humidity, the decomposition of carbon and the soil thermal conductivity. These changes in turn lead to new processes and interactions between vegetation and moisture (soil and air), carbon cycle, energy balance, etc. For the boreal C3 grasses we did not include new processes compared to the generic C3 grass PFT, but improved the realism of the carbon and water budgets with new boreal adjusted parameters. We assess the performance of the modified ORCHIDEE land surface model and in particular its ability to represent the new plant types (their phenology etc.), and evaluate the effects of these new PFTs on the simulated energy, water and carbon balances of boreal ecosystems. The potential impact of these refinements on future climate simulations will be discussed.

  16. Remote sensing analysis of desert vegetation and its landscape changes: The case in middle reaches of Tarim River Basin, Xinjiang, China

    王让会; 樊自立; 张慧芝; 陈亚萍; 马映军

    2002-01-01

    Based on remote sensing information sources including B/W aerial photos of 1983,pseudo-color aerial photos of 1992 and JERS-1/OPS VNIR image of 1996, vegetation types ofYingbazha, in the middle reaches of the Tarim River Basin in Xinjiang, China are mapped usingARC/INFO and related software. The changes in vegetation areas and distribution conditions areanalyzed. As a result of natural and human influences, vegetation changes have temporal andspatial characteristics. According to the principles of landscape ecology and geographical informa-tion science, the landscape changes are indicated. Moreover, the remote sensing and GIS tech-niques are integrated to study vegetation and its landscape.

  17. Spatial Vegetation Data for Gateway National Recreation Area Vegetation Mapping Project

    National Park Service, Department of the Interior — Vegetation map of Gateway National Recreation Area provides local names for vegetation types, as well as crosswalks to the National Vegetation Classification System...

  18. Spatial Vegetation Data for Johnstown Flood National Memorial Vegetation Mapping Project

    National Park Service, Department of the Interior — Vegetation map of Johnstown Flood National Memorial provides local park-specific names for vegetation types, as well as crosswalks to the National Vegetation...

  19. Influence of the type of vegetable oil on the drug release profile from lipid-core nanocapsules and in vivo genotoxicity study.

    Rigo, Lucas Almeida; Frescura, Viviane; Fiel, Luana; Coradini, Karine; Ourique, Aline Ferreira; Emanuelli, Tatiana; Quatrin, Andréia; Tedesco, Solange; Silva, Cristiane B da; Guterres, Silvia Staniçuaski; Pohlmann, Adriana Raffin; Beck, Ruy Carlos Ruver

    2014-11-01

    The use of rice bran (RB), soybean (SB) or sunflower seed (SF) oils to prepare lipid-core nanocapsules (LNCs) as controlled drug delivery systems was investigated. LNCs were prepared by interfacial deposition using the preformed polymer method. All formulations showed negative zeta potential and adequate nanotechnological characteristics (particle size 220-230  nm, polydispersity index oils did not present genotoxic potential. Clobetasol propionate (CP) was selected as a model drug to evaluate the influence of the type of vegetable oil on the control of the drug release from LNCs. Biphasic drug release profiles were observed for all formulations. After 168  h, the concentration of drug released from the formulation containing SF oil was lower (0.36  mg/mL) than from formulations containing SB (0.40  mg/mL) or RB oil (0.45  mg/mL). Good correlations between the consistency indices for the LNC cores and the burst and sustained drug release rate constants were obtained. Therefore, the type of the vegetal oil was shown as an important factor governing the control of drug release from LNCs.

  20. [Demography and human ecology].

    Nazareth, J M

    1993-01-01

    At the end of the 19th century the German biologist Ernest Haekel was the first scientist to use the term ecology, which was defined as the study of relationships of organisms or groups of organisms with the environment and indicated the interdependence of the living world, including plants, animals, and humans. This concept also indicates a continuous process of adaptation of organisms to their external environment. The basic concepts of scientific ecology, which developed at the end of the 19th century, can be attributed to Darwin: the relationships between living beings and the notion of the process of adaptation to their environment. The term human ecology appeared in the early 1920s. Human ecology embodies fundamental ideas: biotype, habitat, community, biocenosis, ecosystem, biomass, interchange and equilibrium, and circulation of energy. The accumulated knowledge about human ecology is broken down using the criteria of topography (ecology of humid forests, deserts, lakes, etc.); followed by the appearance of species; and the variants of classical division: auto ecology (influence of external factors on living beings) and sinecology (the study of groups of associated organisms, i.e., natural, animal, and vegetation communities). The species are considered on the basis of equality or sinecology (all of them have the same interests), while in human ecology a species is determined by its relation to a reference group--autoecology or anthropocentric ecology. In 1911, J. Thompson bridged the gap between biological knowledge and social sciences; in 1921, H. Barrows identified human ecology as a component of geography; in 1925, L. Bernard presented the classification of ecosystems; and in 1936, Ezra Park published his work, Human Ecology, followed in 1945 by the emergence of the Chicago school. Demography and human ecology are intimately connected because population is the result of natural and migratory movements, therefore the two sciences require a methodology

  1. Quantitative relationship between pollen and vegetation in northern China

    XU QingHai; LI YueCong; YANG XiaoLan; ZHENG ZhenHua

    2007-01-01

    and Nitraria, and their pollen percentages are less than 1% where original plant are absent. Caragana and Spiraea pollen percentages have some relations with vegetation cover. The relations between pollen percentages and vegetation cover are not clear for Rosaceae and Saxifragaceae. For herb pollen types, Cyperaceae pollen has the closest correlation with vegetation cover, where pollen percentages are more than 20% when Cyperaceae are constructive or dominant species in vegetation, and pollen percentages are less than 5% where Cyperaceae are not constructive or dominant species(cover less than 30%).Artemisia and Chenopodiaceae pollen percentages mainly have close relations with ecological regions. The relations between pollen percentages and cover are not clear for Gramineae, Leguminosae nosae and Compositae.

  2. [Change trend of vegetation cover in Beijing metropolitan region before and after the 2008 Olympics].

    Sun, Xiao-Peng; Wang, Tian-Ming; Wu, Jian-Guo; Ge, Jian-Ping

    2012-11-01

    The MODIS-NDVI data from 2000 to 2009 were used to analyze the temporal dynamics and spatial distribution of the vegetation cover in the Beijing metropolitan region before and after the 2008 Olympics. During the study period, the proportion of the significantly increased pixels of NDVI occupied 20.7% while that of the significantly decreased pixels only occupied 4.1% of the total, and the decreasing rate of the NDVI was slightly faster than the increasing rate. The significant changes of the NDVI were mainly concentrated in the low altitude and small slope areas with intensive human activities, and two bands were formed in the plain area, i. e., the vegetation increasing band within the 5th Ring Road and the vegetation decreasing band from the 5th Ring Road to the outside areas of the 6th Ring Road. In the areas with significant vegetation change, there was an obvious transition between the high and low NDVI sections but less change in the medium NDVI section, mainly due to the conversion of land cover type. In the Capital function core area and ecological conservation zones, vegetation change represented a positive trend; while in the urban function expansion area and urban development area, vegetation change had the dual characteristics of both positive and negative trends. A series of ecological engineering projects during the preparatory period of the 2008 Olympics was the main cause of the vegetation increase in the study area.

  3. Dynamic monitoring of landscape patterns and ecological processes using HJ-1 and SPOT satellite data over Hulunbeier grassland, China

    Feng Zhang; Ying Li; Sihan Liu; Shaohua Zhao; Yanting Wu

    2014-03-01

    Landscape patterns and ecological processes have been in long-term research focus in the field of landscape ecology, but how to measure their quantitative relations is still open. This work chooses the Hulunbeier grassland as the study area where ecosystem shows high vulnerability, frequent evolvement of landscape patterns and ecological processes. With remote sensing technology, the relationships between landscape patterns and ecological processes were analyzed quantitatively from multi-scale, multitemporal and time series perspective. Firstly, the information about the current situation and change of landscape patterns and ecological processes are obtained from HJ-1 (Environmental and Disaster Small Satellite) and LANDSAT TM (Thermal Mapper) data. Secondly, SPOT NDVI (Normalized Difference Vegetation Index) data during 2000–2008 are used to analyze the dynamic changes of ecological processes, and to simulate its inter-annual variety at pixel scale. Finally, the dynamic change trends of ecological processes of grassland vegetation are described. The results indicate that the unchanged ecosystem types account for most of the study area, unused land in the central part expands continuously which results in the increase of desertification, and most ecosystem types in the eastern part are changed to grassland and woodland. Furthermore, the vegetation vulnerability is the highest in the grassland-dominated region, the second in grassland–farmland–woodland transition, and the smallest in the woodland-dominated region, where the stability is enhanced in turn. Due to the dynamic change of vegetation, it can be concluded that the study area underwent ecological processes of vegetation cover with a negative trend and a changed phenology.

  4. Distribution of phytoplankton functional types in high-nitrate low-chlorophyll waters in a new diagnostic ecological indicator model

    Palacz, Artur; St. John, Michael; Brevin, R.J.W.

    2013-01-01

    and temporal distribution of phyto-PFTs. We apply an innovative ecological indicator approach to modeling PFTs, and focus on resolving the question of diatom-coccolithophore co-existence in the subpolar high-nitrate and low-chlorophyll regions. We choose an artificial neural network as our modeling framework...

  5. Administrative Ecology

    McGarity, Augustus C., III; Maulding, Wanda

    2007-01-01

    This article discusses how all four facets of administrative ecology help dispel the claims about the "impossibility" of the superintendency. These are personal ecology, professional ecology, organizational ecology, and community ecology. Using today's superintendency as an administrative platform, current literature describes a preponderance of…

  6. The influence of soil type, vegetation cover and soil moisture on spin up behaviour of a land surface model in a monsoonal region

    Bhattacharya, Anwesha; Mandal, Manabottam

    2015-04-01

    Model spin-up is the process through which the model is adequately equilibrated to ensure balance between the mass fields and velocity fields. In this study, an offline one dimensional Noah land surface model is integrated recursively for three years to assess its spin-up behavior at different sites over the Indian Monsoon domain. Several numerical experiments are performed to investigate the impact of soil category, vegetation cover, initial soil moisture and subsequent dry or wet condition on model spin-up. These include simulations with the dominant soil and vegetation covers of this region, different initial soil moisture content (observed soil moisture; dry soil; moderately wet soil; saturated soil), simulations initialized at different rain conditions (no rain; infrequent rain; continuous rain) and different seasons (Winter, Spring, Summer/Pre-Monsoon, Monsoon and Autumn). It is seen that the spin-up behavior of the model depends on the soil type and vegetation cover with soil characteristics having the larger influence. Over India, the model has the longest spin-up in the case of simulations with loamy soil covered with mixed-shrub. It is noted that the model has a significantly longer spin-up when initialized with very low initial soil moisture content than with higher soil moisture content. It is also seen that in general, simulations initialized just before a continuous rainfall event have the least spin-up time. This observation is reinforced by the results from the simulations initialized in different seasons. It is seen that for monsoonal region, the model spin-up time is least for simulations initialized just before the Monsoon. Model initialized during the Monsoon rain episodes has a longer spin-up than that initialized in any other season. Furthermore, it is seen that the model has a shorter spin-up if it reaches the equilibrium state predominantly via drying process and could be as low as two months under quasi-equilibrium condition depending on

  7. Runoff and erosion in a pinon-juniper woodland: Influence of vegetation patches

    Reid, K.D.; Wilcox, B.P.; Breshears, D.D.; MacDonald, L.

    1999-12-01

    In many semiarid regions, runoff and erosion differ according to vegetation patch type. These differences, although hypothesized to fundamentally affect ecological processes, have been poorly quantified. In a semiarid pinion-juniper woodland [Pinus edulis Engelm. and Juniperus monosperma (Engelm) Sarg.] in northern New Mexico, the authors measured runoff and erosion from the three patch types that compose these woodlands: Canopy patches (those beneath woody plants), vegetated patched in intercanopy areas, and bare patches in intercanopy areas. The bare intercanopy patches exhibited the highest rates, followed by vegetated intercanopy patches and then by canopy patches. Large convective summer storms, though relatively infrequent, generated much of the runoff and most of the sediment; prolonged frontal storms were capable of generating considerable runoff but little sediment. A portion of the runoff and most of the sediment generated from bare intercanopy patches was redistributed down-slope, probably to adjacent vegetated intercanopy patches, demonstrating connectivity between these two patch types. Their results indicate that there are significant and important differences in runoff and sediment production from the three patch types; that bare intercanopy patches act as sources of both water and sediment for the vegetated intercanopy patches; and that the transfer of water and sediment at small scales is both frequent enough and substantial enough to be considered ecologically significant.

  8. Vegetative response to water availability on the San Carlos Apache Reservation

    Petrakis, Roy; Wu, Zhuoting; McVay, Jason; Middleton, Barry R.; Dye, Dennis G.; Vogel, John M.

    2016-01-01

    On the San Carlos Apache Reservation in east-central Arizona, U.S.A., vegetation types such as ponderosa pine forests, pinyon-juniper woodlands, and grasslands have significant ecological, cultural, and economic value for the Tribe. This value extends beyond the tribal lands and across the Western United States. Vegetation across the Southwestern United States is susceptible to drought conditions and fluctuating water availability. Remotely sensed vegetation indices can be used to measure and monitor spatial and temporal vegetative response to fluctuating water availability conditions. We used the Moderate Resolution Imaging Spectroradiometer (MODIS)-derived Modified Soil Adjusted Vegetation Index II (MSAVI2) to measure the condition of three dominant vegetation types (ponderosa pine forest, woodland, and grassland) in response to two fluctuating environmental variables: precipitation and the Standardized Precipitation Evapotranspiration Index (SPEI). The study period covered 2002 through 2014 and focused on a region within the San Carlos Apache Reservation. We determined that grassland and woodland had a similar moderate to strong, year-round, positive relationship with precipitation as well as with summer SPEI. This suggests that these vegetation types respond negatively to drought conditions and are more susceptible to initial precipitation deficits. Ponderosa pine forest had a comparatively weaker relationship with monthly precipitation and summer SPEI, indicating that it is more buffered against short-term drought conditions. This research highlights the response of multiple, dominant vegetation types to seasonal and inter-annual water availability. This research demonstrates that multi-temporal remote sensing imagery can be an effective tool for the large scale detection of vegetation response to adverse impacts from climate change and support potential management practices such as increased monitoring and management of drought-affected areas. Different

  9. Presettlement Vegetation

    Minnesota Department of Natural Resources — Presettlement vegetation of Minnesota based on Marschner's original analysis of Public Land Survey notes and landscape patterns. Marschner compiled his results in...

  10. Vegetation type and age drive changes in soil properties, nitrogen and carbon sequestration in urban parks under cold climate

    Heikki Martti Setälä

    2016-08-01

    Full Text Available Urban green spaces provide ecosystem properties fundamental to the provision of ecosystem services, such as the sequestration of carbon and nutrients and serving as a reservoir for organic matter. Although urban vegetation influences soil physico-chemical properties, it remains unknown whether ecosystem properties depend on plant species portfolios. We tested the influence of three common functional plant groups (evergreen trees, deciduous trees, grass/lawn for their ability to modify soils in parks of various ages under cold climatic conditions in Finland. We hypothesized that (i plant functional groups affect soils differently resulting in divergent ecosystem properties, and (ii that these ecosystem properties also depend on park age. We included 41 urban parks of varying ages (10, 50 and > 100 years and additional control forests. Park soils were sampled for physico-chemical parameters up to 50 cm depth. Our data indicate that plant functional groups modify soils differently, especially between the evergreen and lawn treatments at 50 and > 100 year old parks. Soils under evergreen trees had the lowest pH and generally the highest percentage organic matter, percentage total carbon and percentage total nitrogen. Soil pH remained the same, whereas concentrations of organic matter, total carbon and total nitrogen declined by depth. Soils in the reference forests had lower pH but higher percentages organic matter, total carbon and total nitrogen than those in parks. We estimate that old parks with evergreen trees can store 35.5 kg C m-2 and 2.3 kg N m-2 – considerably more than in urban soils in warmer climates. Our data suggest that plant-soil interactions in urban parks, in spite of being constructed environments, are surprisingly similar to those in natural forests.

  11. Enrichment Difference of Different Types of Vegetables to Heavy Metals%不同种类蔬菜对土壤重金属的富集差异

    韩峰; 高雪; 陈海燕

    2014-01-01

    To explore the feasibility of planting vegetaldes on the land with heavy metal content above the national standard,a field contrast experiment was conducted to analyze the contents of heavy metals (Cd,Hg,As,Pb)in 12 vegetable variety samples planted in soils with heavy metals exceed standard,and the pollution levels were evaluated in the paper.The results indicated that cucumber had the strongest enrichment capacity for Cd,celery had the strongest enrichment capacity for Hg,all vegetables had weak enrichment capability on As and Pb.Single factor pollution index Cd in cucumber,cabbage,lettuce, radish and kidney beans were 3.260,3.140,2.900,2.520,and 1.900,respectively,which were moderate and above pollution level.Hg reached severe and above polluted in celery,radish,carrot,eggplant, lettuce loofah,and cabbage.Whereas,both As and Pb had no significant effect on quality in different vegetable varieties,which reached clean level.Therefore,it was suggested that under the detection of heavy metal contents in the soil,and according to the differences of heavy metal absorption in different vegetables,selectively plant different vegetables types to avoid the exceed of heavy metal contents,and to expand the planting areas of vegetables in Guizhou.%为探索重金属含量超标的耕地种植蔬菜的可行性,通过田间种植对比试验,分析了 Cd、Hg、As、Pb 超标土壤上12个蔬菜品种中的重金属含量,并对污染程度进行了评价。结果表明:黄瓜、芹菜分别对 Hg、Cd 的富集能力最强,各类蔬菜均对 As 和 Pb 富集能力较弱。黄瓜、大白菜、生菜、萝卜和棒豆中 Cd的单因子污染指数分别为3.260、3.140、2.900、2.520和1.900,达中度及以上污染水平;Hg 达到重度污染水平以上的蔬菜品种有芹菜、萝卜、胡萝卜、茄子、生菜、丝瓜和大白菜;As 和 Pb 均达清洁水平,对不同蔬菜品种质量均无显著影响。在 As、Pb

  12. Interaction type influences ecological network structure more than local abiotic conditions: evidence from endophytic and endolichenic fungi at a continental scale.

    Chagnon, Pierre-Luc; U'Ren, Jana M; Miadlikowska, Jolanta; Lutzoni, François; Arnold, A Elizabeth

    2016-01-01

    Understanding the factors that shape community assembly remains one of the most enduring and important questions in modern ecology. Network theory can reveal rules of community assembly within and across study systems and suggest novel hypotheses regarding the formation and stability of communities. However, such studies generally face the challenge of disentangling the relative influence of factors such as interaction type and environmental conditions on shaping communities and associated networks. Endophytic and endolichenic symbioses, characterized by microbial species that occur within healthy plants and lichen thalli, represent some of the most ubiquitous interactions in nature. Fungi that engage in these symbioses are hyperdiverse, often horizontally transmitted, and functionally beneficial in many cases, and they represent the diversification of multiple phylogenetic groups. We evaluated six measures of ecological network structure for >4100 isolates of endophytic and endolichenic fungi collected systematically from five sites across North America. Our comparison of these co-occurring interactions in biomes ranging from tundra to subtropical forest showed that the type of interactions (i.e., endophytic vs. endolichenic) had a much more pronounced influence on network structure than did environmental conditions. In particular, endophytic networks were less nested, less connected, and more modular than endolichenic networks in all sites. The consistency of the network structure within each interaction type, independent of site, is encouraging for current efforts devoted to gathering metadata on ecological network structure at a global scale. We discuss several mechanisms potentially responsible for such patterns and draw attention to knowledge gaps in our understanding of networks for diverse interaction types.

  13. 石羊河流域海拔、植被覆盖与景观类型空间关系研究%Spatial relationship between elevation, vegetation cover and landscape types in Shiyang River Basin

    魏伟; 石培基; 赵军; 王旭峰

    2012-01-01

    complex,and the regression result about them were not very perfect. Seen from the whole study area, the landscape developed to the heterogeneous direction, this indi- cated that the proportional difference among various landscapes types was increasing, this kind of change has reflec- ted the human activity's influence to the whole landscape to a certain extent. However, the study provides a refer- ence to the landscape pattern and its optimization as well as ecological planning and management. The thoughtway and results were significant for vegetation and ecological environment changes in the arid inland revier basin. Using RS and GIS technology, we can understand the spatial relationship betwwen elevation, vegetation cover and land- scape Types through quantitative analysis in spatial patterns. This technology can explore idiographic landscape structures and related problems of the study area. However, the analysis data is not very ideal. For example, RS im- ages scan cycle is long and its spatial resolution is poor. So it is difficult to get better images of grassland in the growing season under the interferential condition. The data is too complex to analyze one by one. Some results have shortages in calculating and analyzing precision. It will be ameliorated in the future study.%以Landsat/TM为数据源,在桌面GIS支持下解译出研究区各景观类型,根据植被的生长周期,结合植被指数NDVI作为研究因子,采用目前较为流行的主成分变换法(PCA),结合景观类型图和数字高程模型(DEM),参考相关地理基础图件,对石羊河流域海拔和植被覆盖进行分级分类。运用叠置分析法研究了不同海拔高度和不同植被覆盖下NDVI变化情况;同时分析了各景观类型与海拔和植被覆盖三者之间的空间关系。结果表明:研究区各景观类型大体依海拔呈垂直性分布,各自然要素组成垂直分异性特征亦较为明显。植被覆盖、景观类

  14. Quantitative relationship between pollen and vegetation in northern China

    2007-01-01

    , Tamariaceae and Nitraria, and their pollen percentages are less than 1% where original plant are absent. Caragana and Spiraea pollen percentages have some relations with vegetation cover. The relations between pollen percentages and vegetation cover are not clear for Rosaceae and Saxifragaceae. For herb pollen types, Cyperaceae pollen has the closest correlation with vegetation cover, where pollen percentages are more than 20% when Cyperaceae are constructive or dominant species in vegetation, and pollen per- centages are less than 5% where Cyperaceae are not constructive or dominant species (cover less than 30%). Artemisia and Chenopodiaceae pollen percentages mainly have close relations with ecological regions. The relations between pollen percentages and cover are not clear for Gramineae, Legumi- nosae and Compositae.

  15. Response of Coprophagus Beetles (Coleoptera: Scarabaeidae on changes of vegetation structure in various habitat types at Lore Lindu National Park, Central Sulawesi

    CHRISTIAN H. SCHULZE

    2007-01-01

    Full Text Available This study analysed the response of dung beetles − a group of beetles which play a major role in decomposition of dung and animal carcasses − to changes of vegetation structure due to forest conversion to different human-made habitat types at the margin of Lore Lindu National Park. Therefore, dung beetles were sampled at natural forest, cacao agroforestry systems and open area. A total of 28 species of coprophagus beetle species were recorded from the sampled sites. Species richness and abundance of dung beetles, particularly of large species, decreased from forest towards agroforestry systems and open areas. However, more than 80 % of the species recorded in natural forest were found in cacao agroforestry systems Of the measured habitat parameters, particularly the number of tree species, air temperature, and canopy cover had a significant power for explaining changes in dung beetle ensembles along the gradient of land-use intensity.

  16. Analyses on types and characteristics of community of urban semi-natural vegetation in Urumqi%乌鲁木齐城市半自然植被群落类型及特征分析

    南伟疆; 昝勤; 姜逢清; 王蕾; 严成; 尹林

    2011-01-01

    Based on previous study results and combined with investigation of typical sampling plots,community types of urban semi-natural vegetation in Urumqi were classified, and characteristics of community structure, species composition and plant growth-form spectrum were analyzed. The results show that types of urban semi-natural vegetation in Urumqi can be divided into four vegetation races,thirty-three vegetation types and thirty-eight association groups. In which, broadleaved forest vegetation race includes eight vegetation types and eleven association groups; shrub vegetation race does twelve vegetation types and twelve association groups; herb vegetation race does ten vegetation types and eleven association groups; vegetation race associated with human does three vegetation types and four association groups. The number of vegetation types and association groups in shrub vegetation race are the most,while those in vegetation race associated with human are the fewest. In the urban semi-natural vegetation community, the synusium of broadleaved forest vegetation race are two- and three- layers, that of shrub vegetation race mainly two-layer, those of herb vegetation race and vegetation race associated with human one-layer. The synusium types mainly are single herb type, arbor-shrub type and shrub-herb type. There are eighty-eight species of spermatophyte belonging to seventy-four genera of twenty-four families in the urban semi-natural vegetation community, the dominant families are Gramineae, Chenopodiaceae,Leguminosae, Compositae, Rosaceae and Cruciferae, containing forty-seven genera and fifty-seven species accounting for 63.51% and 64.77% of total number of genera and species of spermatophyte respectively in the community. In the community, annual and perennial herbs and perennial semishrub species are more with a percentage of 29.55%, 34.10% and 17.04% of total species, respectively.According to related results, the differences between the urban semi

  17. Seasonal variation and controlling factors of soil carbon effluxes in six vegetation types in southeast of Sweden

    Tagesson, Torbern (Dept. of Physical Geography and Ecosystem Analysis, Lund Univ., Lund (SE))

    2007-11-15

    Soil carbon effluxes of a pine stand, a spruce stand, a lichen rock, two oak stands and a meadow in the Laxemar investigation area in south-eastern Sweden (57 deg 5 N, 16 deg 7 E) have been measured with the closed chamber technique at 14 occasions between 23 of March 2004 and 10th of March 2005. Soil temperature at 10 cm depth, air temperature, soil moisture and photosynthetically active radiation (PAR) were also measured. Exponential regressions with soil respiration against air and soil temperature were used to estimate soil respiration between 15th of March 2004 and 14th of March 2005. A light response curve with Gross Primary Production (GPP) against PAR and a cubic regression with GPP against air temperature were used for modelling GPP in meadow for the growing season, 15th of March to 31st of October 2004. The exponential regressions with soil respiration against air and soil temperature explained on average 30.6% and 47.6% of the variation, respectively. Soil moisture had a linear limiting effect on soil respiration for all ecosystems but spruce, where soil moisture was the limiting factor above a threshold value of about 50%vol. In the forest ecosystems, GPP of the ground vegetation were not reducing soil carbon effluxes, while in meadow it was. In meadow, the light response curve with GPP against PAR explained 32.7% of the variation in GPP while the cubic regression against air temperature explained 33.9%. No significant effect of soil moisture on GPP was detected. The exponential regression equations with air and soil temperature against soil respiration could be used to temporally extrapolate the occasional field measurements. The light response curve with GPP against PAR and the cubic regression with GPP against air temperature could also be used for temporal extrapolation. From the modelled soil respiration, annual soil respiration for the ecosystems in Laxemar, during 15th of March 2004 to 14th of March 2005, were estimated to be between 0.56 and 1

  18. Exposure of trees to drought-induced die-off is defined by a common climatic threshold across different vegetation types.

    Mitchell, Patrick J; O'Grady, Anthony P; Hayes, Keith R; Pinkard, Elizabeth A

    2014-04-01

    Increases in drought and temperature stress in forest and woodland ecosystems are thought to be responsible for the rise in episodic mortality events observed globally. However, key climatic drivers common to mortality events and the impacts of future extreme droughts on tree survival have not been evaluated. Here, we characterize climatic drivers associated with documented tree die-off events across Australia using standardized climatic indices to represent the key dimensions of drought stress for a range of vegetation types. We identify a common probabilistic threshold associated with an increased risk of die-off across all the sites that we examined. We show that observed die-off events occur when water deficits and maximum temperatures are high and exist outside 98% of the observed range in drought intensity; this threshold was evident at all sites regardless of vegetation type and climate. The observed die-off events also coincided with at least one heat wave (three consecutive days above the 90th percentile for maximum temperature), emphasizing a pivotal role of heat stress in amplifying tree die-off and mortality processes. The joint drought intensity and maximum temperature distributions were modeled for each site to describe the co-occurrence of both hot and dry conditions and evaluate future shifts in climatic thresholds associated with the die-off events. Under a relatively dry and moderate warming scenario, the frequency of droughts capable of inducing significant tree die-off across Australia could increase from 1 in 24 years to 1 in 15 years by 2050, accompanied by a doubling in the occurrence of associated heat waves. By defining commonalities in drought conditions capable of inducing tree die-off, we show a strong interactive effect of water and high temperature stress and provide a consistent approach for assessing changes in the exposure of ecosystems to extreme drought events.

  19. Dissolved inorganic nitrogen pools and surface flux under different brackish marsh vegetation types, common reed (Phragmites australis) and salt hay (Spartina patens)

    Windham-Myers, L.

    2005-01-01

    The current expansion of Phragmites australis into the high marsh shortgrass (Spartina patens, Distichlis spicata) communities of eastern U.S. salt marshes provided an opportunity to identify the influence of vegetation types on pools and fluxes of dissolved inorganic nitrogen (DIN). Two brackish tidal marshes of the National Estuarine Research Reserve system were examined, Piermont Marsh of the Hudson River NERR in New York and Hog Island in the Jacques Coustaeu NERR of New Jersey. Pools of DIN in porewater and rates of DIN surface flux were compared in replicated pairs of recently-expanded P. australis and neighboring S. patens-dominated patches on the high marsh surface. Both marshes generally imported nitrate (NO3-) and exported ammonium (NH4+), such that overall DIN was exported. No differences in surface exchange of NO3- or NH4+ were observed between vegetation types. Depth-averaged porewater NH4+ concentrations over the entire growing season were 56% lower under P. australis than under S. patens (average 1.4 vs. 3.2 mg NH4+ L-1) with the most profound differences in November. Porewater profiles showed an accumulation of NH4+ at depth in S. patens and constant low concentrations in P. australis from the soil surface to 50 cm depth, with no significant differences in porewater salinity. Despite these profound differences in porewater, NH 4+ diffusion from soils of P. australis and S. patens were not measurably different, were similar to other published rates, and were well below estimated rates based on passive diffusion alone. Rapid adsorption and uptake by litter and microbes in surface soils of both communities may buffer NH4+ loss to flooding tides in both communities, thereby reducing the impact of P. australis invasion on NH4+ flux to flooding waters. ?? Springer 2005.

  20. Non-free ionic transport of sodium, magnesium, and calcium in streams of two adjacent headwater catchments with different vegetation types in Japan

    Terajima, Tomomi; Moriizumi, Mihoko; Nakamura, Tomohiro

    2017-01-01

    Sodium (Na), magnesium (Mg), calcium (Ca) are usually believed to occur mostly as free ions in the fresh water and consequently little is known about their chemical species. To understand the importance of non-free ionic fractions (NIF) of major metals in freshwater streams, Na, Mg, Ca, silicon (Si), and fulvic acid-like materials (FAM) were measured in streams of mountainous adjacent headwater catchments dominated by different vegetation types (planted evergreen coniferous forest and natural deciduous broadleaf forest). During both no rainfall periods and rainstorms, the proportion of NIF relative to total elements was lower in the coniferous catchment than in the deciduous catchment, although it sometimes accounted for half or more of the total concentrations of Na, Mg, and Ca in both catchments. The solubility of metal compounds was higher than the measured maximum concentrations of Na+, Mg2+, and Ca2+ to the extent that inorganic bonding was hardly possible. During no rainfall periods when FAM was slightly produced into the streams, the fluxes of NIF and Si were highly correlated (r > 0.92, p NIF correlated weakly with that of Si but did not correlate with that of FAM in both catchments. In contrast, during a heavy rainstorm, the flux of NIF correlated strongly (r ⩾ 0.83, p NIF originated in the quick-flow component (i.e., surface or near-surface water) in stream water (ΔNIF) correlated strongly (r ⩾ 0.81, p < 0.0001, n = 22) with that of FAM. These findings imply that heavy rainstorms may enhance the bonding of the major metals with humic substances mainly in the deciduous catchment; and also exhibit that, in the headwater catchments, both water flow pathways resulted from the different vegetation types play a very important role to promote the bonding of major metals with humic substances in stream water.

  1. Mercury mobilisation from soils and ashes after a wildfire and rainfall events: effects of vegetation type and fire severity

    Campos, Isabel; Abrantes, Nelson; Keizer, Jan Jacob; Vale, Carlos; Serpa, Dalila; Pereira, Patrícia

    2016-04-01

    Wildfire is a major disturbance of forests worldwide, with huge environmental impacts. The number of catastrophic wildfires is increasing over the past few decades mainly due to a combined effect of climate change and poor land-use management. Interestingly, wildfires have an important role in contaminants production and mobilization and, thus, on their biogeochemical cycles. For instance, trace elements could be mobilized during a wildfire from burnt vegetation and ashes and may eventually achieve the aquatic systems upon a rainfall period. In this regard, wildfires represent a relevant diffuse source of trace elements to aquatic systems that has, so far, been poorly investigated. The current study aims to mitigate such lack of knowledge for mercury, a well-recognized persistent toxicant with potential harmful impacts on the environment and on human health. Thus, a field study was conducted in two Portuguese forests (Ermida and S. Pedro do Sul, North-centre of Portugal) with distinct fire severity. Fire was classified as moderate in Ermida and moderate to high severity in S. Pedro do Sul. In Ermida, soil samples and ashes were collected in the seven hillslopes (three burnt eucalypt, three burnt pine and one unburnt eucalypt) immediately and 4 months after the fire, the latter following an episode of intense rainfall. In S. Pedro do Sul, sampling took place immediately after the fire in four hillslopes (one burnt eucalypt and three burnt pine). Mercury analysis was performed in an Hg analyser in which samples were thermally decomposed by controlled heating. The final decomposition products were passed through an Hg amalgamator heated to 700 °C and Hg(0) was released and detected by absorption spectrometry at 254 nm. Burnt soil samples showed significantly lower levels of mercury than non-burnt soil, confirming the potential of a forest fire to release accumulated mercury in soil prior to the burning. Such process could be particularly relevant for this element due

  2. The Ecological Role of Type Three Secretion Systems in the Interaction of Bacteria with Fungi in Soil and Related Habitats Is Diverse and Context-Dependent

    Nazir, Rashid; Mazurier, Sylvie; Yang, Pu; Lemanceau, Philippe; van Elsas, Jan Dirk

    2017-01-01

    Bacteria and fungi constitute important organisms in many ecosystems, in particular terrestrial ones. Both organismal groups contribute significantly to biogeochemical cycling processes. Ecological theory postulates that bacteria capable of receiving benefits from host fungi are likely to evolve efficient association strategies. The purpose of this review is to examine the mechanisms that underpin the bacterial interactions with fungi in soil and other systems, with special focus on the type III secretion system (T3SS). Starting with a brief description of the versatility of the T3SS as an interaction system with diverse eukaryotic hosts, we subsequently examine the recent advances made in our understanding of its contribution to interactions with soil fungi. The analysis used data sets ranging from circumstantial evidence to gene-knockout-based experimental data. The initial finding that the abundance of T3SSs in microbiomes is often enhanced in fungal-affected habitats like the mycosphere and the mycorrhizosphere is now substantiated with in-depth knowledge of the specific systems involved. Different fungal–interactive bacteria, in positive or negative associations with partner fungi, harbor and express T3SSs, with different ecological outcomes. In some particular cases, bacterial T3SSs have been shown to modulate the physiology of its fungal partner, affecting its ecological characteristics and consequently shaping its own habitat. Overall, the analyses of the collective data set revealed that diverse T3SSs have assumed diverse roles in the interactions of bacteria with host fungi, as driven by ecological and evolutionary niche requirements. PMID:28197129

  3. Vegetation survey of Sengwa

    G. C. Craig

    1983-12-01

    Full Text Available The approach and initial results of a vegetation survey of the Sengwa Wildlife Area are outlined. The objectives were to produce a vegetation classification and map sufficiently detailed to serve as a base for the management of the natural vegetation. The methods adopted consist of (a stratification of the area into homogeneous units using 1:10 000 colour aerial photographs; (b plotless random sampling of each stratum by recording cover abundance on the Braun-Blaunquet scale for all woody species; and (c analysis of the data by indicator species analysis using the computer programme 'Twinspan’. The classification produced is successful in achieving recognizable vegetation types which tie in well with known environmental features.

  4. Forest vegetation of Xishuangbanna, south China

    Zhu Hua

    2006-01-01

    Xishuangbanna of southern Yunnan is biogeographically located at a transitional zone from tropical southeast (SE) Asia to subtropical east Asia and is at the junction of the Indian and Burmese plates of Gondwana and the Eurasian plate of Laurasia. The region, though surprisingly far from the equator and at a relatively high altitude, has a rich tropical flora and a typical tropical rain forest in the lowland areas. Based on physiognomic and ecological characteristics, floristic composition and habitats combined, the primary vegetation in Xishuangbanna can be organized into four main vegetation types: tropical rain forest, tropical seasonal moist forest, tropical montane evergreen broad-leaved forest and tropical monsoon forest. The tropical rain forest can be classified into two subtypes, i.e. a tropical seasonal rain forest in the lowlands and a tropical montane rain forest at higher elevations. The tropical seasonal rain forest has almost the same forest profile and physiognomic characteristics as equatorial lowland rain forests and is a type of truly tropical rain forest. Because of conspicuous similarity on ecological and floristic characteristics, the tropical rain forest in Xishuangbanna is a type of tropical Asian rain forest. However, since the tropical rain forest of Xishuangbanna occurs at the northern edge of tropical SE Asia, it differs from typical lowland rain forests in equatorial areas in having some deciduous trees in the canopy layer, fewer megaphanerophytes and epiphytes but more abundant lianas and more plants with microphyll. It is a type of semi-evergreen rain forest at the northern edge of the tropical zone. The tropical montane rain forest occurs at wet montane habitats and is similar to the lower montane rain forest in equatorial Asia in floristic composition and physiognomy. It is a type of lower montane rain forests within the broader category of tropical rain forests. The tropical seasonal moist forest occurs on middle and upper

  5. Lake Victoria wetlands and the ecology of the Nile tilapia, oreochromis niloticus linn,.

    Balirwa, J.S.

    1998-01-01

    An ecological study of wetlands was undertaken in northern Lake Victoria (East Africa) between 1993 and 1996 with a major aim of characterising shallow vegetation-dominated interface habitats, and evaluating their importance for fish, in particular, for the stocked and socio-economically important Oreochromis niloticus LINNÉ (the Nile tilapia). From field and laboratory experiments, five major habitat types could be defined by the type of the dominant emergent macrophyte at the shore from the...

  6. Airborne Spectral BRDF of Various Surface Types (Ocean, Vegetation, Snow, Desert, Wetlands, Cloud Decks, Smoke Layers) for Remote Sensing Applications

    Gatebe, Charles K.; King, Michael D.

    2016-01-01

    In this paper we describe measurements of the bidirectional reflectance-distribution function (BRDF) acquired over a 30-year period (1984-2014) by the National Aeronautics and Space Administration's (NASA's) Cloud Absorption Radiometer (CAR). Our BRDF database encompasses various natural surfaces that are representative of many land cover or ecosystem types found throughout the world. CAR's unique measurement geometry allows a comparison of measurements acquired from different satellite instruments with various geometrical configurations, none of which are capable of obtaining such a complete and nearly instantaneous BRDF. This database is therefore of great value in validating many satellite sensors and assessing corrections of reflectances for angular effects. These data can also be used to evaluate the ability of analytical models to reproduce the observed directional signatures, to develop BRDF models that are suitable for sub-kilometer-scale satellite observations over both homogeneous and heterogeneous landscape types, and to test future spaceborne sensors. All of these BRDF data are publicly available and accessible in hierarchical data format (http:car.gsfc.nasa.gov/).

  7. Plant traits demonstrate that temperate and tropical giant eucalypt forests are ecologically convergent with rainforest not savanna.

    Tng, David Y P; Jordan, Greg J; Bowman, David M J S

    2013-01-01

    Ecological theory differentiates rainforest and open vegetation in many regions as functionally divergent alternative stable states with transitional (ecotonal) vegetation between the two forming transient unstable states. This transitional vegetation is of considerable significance, not only as a test case for theories of vegetation dynamics, but also because this type of vegetation is of major economic importance, and is home to a suite of species of conservation significance, including the world's tallest flowering plants. We therefore created predictions of patterns in plant functional traits that would test the alternative stable states model of these systems. We measured functional traits of 128 trees and shrubs across tropical and temperate rainforest - open vegetation transitions in Australia, with giant eucalypt forests situated between these vegetation types. We analysed a set of functional traits: leaf carbon isotopes, leaf area, leaf mass per area, leaf slenderness, wood density, maximum height and bark thickness, using univariate and multivariate methods. For most traits, giant eucalypt forest was similar to rainforest, while rainforest, particularly tropical rainforest, was significantly different from the open vegetation. In multivariate analyses, tropical and temperate rainforest diverged functionally, and both segregated from open vegetation. Furthermore, the giant eucalypt forests overlapped in function with their respective rainforests. The two types of giant eucalypt forests also exhibited greater overall functional similarity to each other than to any of the open vegetation types. We conclude that tropical and temperate giant eucalypt forests are ecologically and functionally convergent. The lack of clear functional differentiation from rainforest suggests that giant eucalypt forests are unstable states within the basin of attraction of rainforest. Our results have important implications for giant eucalypt forest management.

  8. Spatial Vegetation Data for Florissant Fossil Beds National Monument Vegetation Mapping Project

    National Park Service, Department of the Interior — The vegetation units on this map were determined through the stereoscopic interpretation of aerial photographs supported by field sampling and ecological analysis....

  9. Kuchler Vegetation

    California Department of Resources — 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...

  10. Ecological bioavailability of permethrin and p,p'-DDT: toxicity depends on type of organic matter resource.

    de Perre, Chloé; Trimble, Andrew J; Maul, Jonathan D; Lydy, Michael J

    2014-02-01

    Hydrophobic organic contaminants readily partition from aqueous to organic phases in aquatic systems with past research largely focusing on sediment. However, within many aquatic systems, matrices such as leaf material and detritus are abundant and ecologically important, as they may represent a primary exposure route for aquatic invertebrates. The objectives of the present study were to examine partitioning and toxicity to Hyalella azteca among permethrin and p,p'-DDT contaminated sediment, leaf, and a sediment-leaf mixture. Log organic carbon-water partitioning coefficients ranged from 4.21 to 5.82 for both insecticides, and were greatest within sediment and lowest in coarse leaf material. H. azteca lethal concentrations for 50% of the population (LC50s) ranged from 0.5 to 111μgg(-1) organic carbon, and were dependent on the matrix composition. The variation in sorption and toxicity among matrices common within stream ecosystems suggests that the ecological niche of aquatic organisms may be important for estimating risk of hydrophobic pesticides.

  11. Diversity and Impacts of Mining on the Non-Volant Small Mammal Communities of Two Vegetation Types in the Brazilian Amazon

    Ardente, Natália Carneiro; Ferreguetti, Átilla Colombo; Gettinger, Donald; Leal, Pricila; Mendes-Oliveira, Ana Cristina; Martins-Hatano, Fernanda; Bergallo, Helena Godoy

    2016-01-01

    The Carajás National Forest contains some of the largest iron ore deposits in the world. The majority of the minerals are found below a plant community known as Savana Metalófila, or “Canga”, which represents only 3% of the landscape within the Carajás National Forest (CNF). The aim of our study was to understand the diversity of community of non-volant small mammals in the two predominant vegetation types: Ombrophilous Forest and Canga, and to examine how mining impacts these communities. Sampling was conducted from January 2010 to August 2011 in 11 sampling sites divided by the total area of Canga and 12 sampling sites in the forest, totalizing 23 sites. Of these, 12 sites (Canga and Forest) were considered impacted areas located close to the mine (<< 900 meters) and 11 sites (Canga and Forest), serving as controls, which were at least 7,000 meters from the mine. We recorded 28 species, 11 from the Order Didelphimorphia and 17 from the Order Rodentia. The two forest types shared 68.42% of the species found in the CNF. A gradient analysis (Non-metric multidimensional scaling) revealed that the first axis clearly separated the non-flying small mammal communities by vegetation type. Occupancy models showed that the detectability of species was affected by the distance from the mining activities. Of all the small mammals analyzed, 10 species were positively affected by the distance from mining in areas impacted (e.g. more likely to be detected farther from mining areas) and detectability was lower in impacted areas. However, three species were negatively affected by the distance from mining, with higher detectability in the impacted areas, and seven species showed no effect of their proximity to mining operations. To date, there are no studies in Brazil about the impact of mining on mammals or other vertebrates. This study reveals that the effect of mining may go beyond the forest destruction caused by the opening of the mining pits, but also may negatively

  12. Application of 3S Techniques in Vegetation Type Investigation in Yajiang%基于3S技术的雅江县植被类型调查与分析

    刘中正; 彭培好; 周正坤

    2013-01-01

    使用TM遥感影像,借助GIS软件进行了影像的处理和解译;制作了植被类型图,计算主要植被类型的面积及其变化情况;分析了3S技术在植被调查中的优势,并调查了植被动态变化,为植被恢复模式的建立提供了依据.%Based on the data available and using the GIS software, we processed and interpreted the Remote Sensing images composed by TM. And we also made the vegetation type chart, in order to calculate the vegetation type area and its change. In this thesis, we explored the advantages of 3S techniques in vegetation investigation and found the dynamic changes in vegetation type area, so as to lay the foundation for building vegetation restoration mode.

  13. Exploring vegetation in the fourth dimension.

    Mitchell, Fraser J G

    2011-01-01

    Much ecological research focuses on changes in vegetation on spatial scales from stands to landscapes; however, capturing data on vegetation change over relevant timescales remains a challenge. Pollen analysis offers unrivalled access to data with global coverage over long timescales. Robust techniques have now been developed that enable pollen data to be converted into vegetation data in terms of individual taxa, plant communities or biomes, with the possibility of deriving from those data a range of plant attributes and ecological indicators. In this review, I discuss how coupling pollen with macrofossil, charcoal and genetic data opens up the extensive pollen databases to investigation of the drivers of vegetation change over time and also provides extensive data sets for testing hypotheses with wide ecological relevance.

  14. 浅析发展高山反季节蔬菜在贵州生态环境建设中的作用%The Functional Analysis of Developing Off-season Vegetables in the Ecological Environment Construction in Guizhou

    刘明智; 陈明霞; 高建强; 方小宁

    2011-01-01

    贵州省地处云贵高原东侧,是我国石漠化较为严重且经济欠发达的农业地区,但这些地区具有适合高山反季节蔬菜种植所需的温度、光照、水分和土壤等自然条件.黔西北、黔西南等地区近些年来的高山反季节蔬菜生产实践表明,贵州海拔500 m以上山区适合种植蔬菜,特别是夏秋蔬菜.在贵州高山地区发展反季节蔬菜,能促进石漠化地区的农业发展和现代生态农业模式的建立,进而促进生态环境的良性发展.%Guizhou is located at the northern Yunnan plateau,it is the agricultural area that is stony desertification badly and economic underdevelopment, but the area has the natural conditions of temperature, highlight, moisture and soil that is suitable for the mountain anti -season vegetables cultivation. The producing practice of the mountain anti -season vegetables in Northwest and Southwest Guizhou indicated that, the mountain area with an elevation of 500 m in Guizhou is suitable for planting vegetables, especially the Xia Qiu vegetables. Developing anti -season vegetables cultivation in mountain area of Guizhou could promote the agricultural development of stony desertification area and the establishment of modern ecological agriculture model, thereby promote the healthy development of ecological environment.

  15. Evaluation and analysis of post-seismic restoration of ecological security in Wenchuan using remote sensing and GIS

    Chunxiang Cao

    2016-11-01

    Full Text Available Aiming at studying the ecological security in Wenchuan, China, where the ecological system had been greatly damaged by the earthquake in 2008, an evaluation indicators system was established based on the pressure–state–response (PSR model, and the indicators were derived from remote sensing images, meteorological data, and statistical data. Ecological security indexes in 2007, 2008, and 2013 were calculated through a comprehensive index method. Then the spatio-temporal analysis on ecological security was conducted. Particularly, the changes of ecological security were centrally analyzed concerning topography, land use types, vegetation coverage, as well as ecological PSR. It is found that the ecological security in Wenchuan presented a distinct vertical-belt distribution. It was damaged by the earthquake, however, it had been improved obviously by 2013, which still did not reach the level in 2007. Meanwhile, the epicentre, the Minjiang River and the southwestern mountains have typically regional characteristics, where the changes of ecological security were analyzed elaborately. The ecological security of these regions had been differently restored compared with 2007. However, there were still some regions with unsafe ecological security. Finally, the studied area was divided into four regions with different protection strategies and some recommendations were provided for further ecological protection.

  16. Plant Type and Its Effects on Canopy Structure at Heading Stage in Various Ecological Areas for a Two-line Hybrid Rice Combination, Liangyoupeijiu

    LU Chuan-gen; HU Ning; YAO Ke-min; XIA Shi-jian; QI Qing-ming

    2010-01-01

    A two-line hybrid rice combination, Liangyoupeijiu, was used to estimate several factors of plant type, and environmental models for these factors at the heading stage were established using the data of eight ecological experimental sites in 2006 and 2007. According to climatic data from 1951 to 2005, the differences in those factors and their effects on plant canopy were analyzed for four rice cropping areas in China, including South China, the middle-lower reaches of the Yangtze River, Sichuan Basin, and river valley in Yunnan, China. The thickness of leaf layer (the distance from pulvinus of the third leaf from the top to the tip of flag leaf) and distribution of leaf area could be used as candidate indices for the plant type of a rice canopy.

  17. Status of urban vegetation in Guangzhou City

    GUAN Dong-sheng; CHEN Yu-juan

    2003-01-01

    According to a survey for the urban vegetation of Guangzhou, urban vegetation has a significantly difference from natural vegetation because of intense human impacts. The research was conducted in a synthetic survey for soil, species diversity, roadside trees and ecological function of urban vegetation in Guangzhou City. The results showed that: (1) soil densities of urban roadside and park forests were higher than mean density of natural forest soil. The pH values of soil in urban roadside were higher too, and the content of organic matter and the concentration of nitrogen were lower. (2) Species diversity of urban vegetation was lower. The most number of species was only 16 species in tree layers of urban forest. (3) Tree growth was limited by narrow space in high-density urban area, where the trees with defects and disorders were common. (4) Comparing with mature natural forests, the productivity of urban vegetation was lower. The effect of urban vegetation on balance of carbon and oxygen were influenced by the low primary production of urban vegetation. Therefore, the growth condition for urban vegetation should be improved. Biodiversity, primary production and ecological function should be increased for urban vegetation in order to improve urban eco-environment.

  18. An interdisciplinary analysis of multispectral satellite data for selected cover types in the Colorado Mountains, using automatic data processing techniques. [hydrology, ecology, geology, vegetation, and mineral deposits

    Hoffer, R. M. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. Documentation is presented of the capability of the middle infrared portion of the electromagnetic spectrum to spectrally differentiate clouds from snow. Other portions of the spectrum cannot provide this capability.

  19. Study on Obstacles to Continuous Cropping of Vegetables and Soil Remediation Technology

    Pingsheng FAN; Gang CHEN; Deli XU; Weimin FENG; Yuyu LU; Anqin GUAN

    2016-01-01

    Firstly,this paper analyzes the cause of obstacles to continuous cropping of vegetables,and then introduces the soil ecological remediation technology used for overcoming obstacles to continuous cropping of vegetables. Finally,this paper analyzes the effect of applying soil ecological remediation technology in overcoming obstacles to continuous cropping of vegetables.

  20. Comprimento da estaca e tipo de substrato na propagação vegetativa de atroveran Shoot cutting length and substrate types on vegetative propagation of atroveran

    Larissa Corrêa do Bomfim Costa

    2007-08-01

    Full Text Available A propagação vegetativa de espécies medicinais vem despertando interesse das pesquisas agronômicas, uma vez que se constitui no ponto de partida e em ferramenta básica para qualquer cultivo em escala comercial. Este trabalho objetivou determinar o comprimento de estaca e o tipo de substrato mais adequados para a propagação vegetativa de atroveran. Em condições de casa de vegetação sob nebulização intermitente, foram testados dois comprimentos de estacas (10 e 20cm e três substratos (areia lavada, casca de arroz carbonizada e substrato comercial Plantmax®, em delineamento experimental em blocos casualizados, com quatro repetições e cinco estacas por parcela. Aos trinta e cinco dias, foram avaliados a porcentagem de enraizamento, o comprimento da maior raiz (cm e a biomassa seca das folhas e das raízes (mg. Os resultados indicaram que a propagação vegetativa de atroveran por meio de estaquia é viável, uma vez que o seu enraizamento médio ficou acima de 70%. As mudas de atroveran obtidas de estacas com 20cm apresentaram maior biomassa seca das folhas e das raízes, apesar de o comprimento da estaca não ter afetado a porcentagem de enraizamento e o comprimento da raiz. Os tipos de substrato não proporcionaram efeito sobre o desenvolvimento das estacas de atroveran. Recomenda-se a produção de mudas de atroveran com estacas de 20cm de comprimento, utilizando-se qualquer um dos três substratos testados.The vegetative propagation of medicinal species is in increasing agronomic interest because it is the starting point and a basic tool for any cultivation in commercial scale. The objective of this work was to determine the best shoot cutting length and the best substrate for vegetative propagation of Ocimum selloi. Cuttings were placed in greenhouse conditions under intermittent mist. Two cutting sizes (10 and 20cm and three substrate types (washed sand, carbonized rice hulls and commercial substrate Plantmax® were tested

  1. Wetland vegetation establishment in L-Lake

    Kroeger, S.R.

    1990-07-01

    Wetland vegetation was transplanted from PAR Pond to L-Lake between January and August, 1987. Approximately 100,000 individual plants representing over 40 species were transplanted along the southern shoreline. Three zones of vegetation were created: (1) submersed/floating-leaved, (2) emergent, (3) upper emergent/shrub. During the summers of 1987, 1988, 1989, the Savannah River Ecology Laboratory sampled the vegetation in 54 permanent transects located in planted (N=32) and unplanted areas (N=22). The 1989 vegetation data from L-Lake were compared to 1985 data from PAR Pond.

  2. The relationship between vegetables and fruits intake and glycosylated hemoglobin values, lipids profiles and nitrogen status in type II inactive diabetic patients

    Marjan Tabesh

    2013-01-01

    Conclusions : Intake of vegetables and fruits may reduce the glycosylated hemoglobin, therefore choosing the appropriate diet with high fruits and vegetables may help to develop antioxidant defense and reduce the HbA1C in diabetic patients but it did not have any impact on lipids profiles, BUN/creatinine and urine protein 24 h.

  3. Seventy-five years of vegetation treatments on public rangelands in the Great Basin of North America

    Pilliod, David S.; Welty, Justin; Toevs, Gordon R.

    2017-01-01

    On the Ground Land treatments occurring over millions of hectares of public rangelands in the Great Basin over the last 75 years represent one of the largest vegetation manipulation and restoration efforts in the world.The ability to use legacy data from land treatments in adaptive management and ecological research has improved with the creation of the Land Treatment Digital Library (LTDL), a spatially explicit database of land treatments conducted by the U.S. Bureau of Land Management.The LTDL contains information on over 9,000 confirmed land treatments in the Great Basin, composed of seedings (58%), vegetation control treatments (24%), and other types of vegetation or soil manipulations (18%).The potential application of land treatment legacy data for adaptive management or as natural experiments for retrospective analyses of effects of land management actions on physical, hydrologic, and ecologic patterns and processes is considerable and just beginning to be realized.

  4. Past and future scenarios of the effect of carbon dioxide on plant growth and transpiration for three vegetation types of southwestern France

    J.-C. Calvet

    2007-04-01

    Full Text Available The sensitivity of an operational CO2-responsive land surface model (the ISBA-A-gs model of Météo-France to the atmospheric CO2 concentration, [CO2], is investigated for 3 vegetation types (winter wheat, irrigated corn, coniferous forest. Past (1960 and future (2050 scenarios of [CO2] corresponding to 320 ppm and 550 ppm, respectively, are explored. The sensitivity study is performed for 4 annual cycles presenting contrasting conditions of precipitation regime and air temperature, based on continuous measurements performed on the SMOSREX site near Toulouse, in southwestern France. A significant CO2-driven reduction of canopy conductance is simulated for the irrigated corn and the coniferous forest. The reduction is particularly large for corn, from 2000 to 2050 (–18%, and triggers a drop in optimum irrigation (–30 mm y−1. In the case of wheat, the response is more complex, with an equal occurrence of enhanced or reduced canopy conductance.

  5. European green lizard (Lacerta viridis) personalities: Linking behavioural types to ecologically relevant traits at different ontogenetic stages.

    Bajer, Katalin; Horváth, Gergely; Molnár, Orsolya; Török, János; Garamszegi, László Zsolt; Herczeg, Gábor

    2015-02-01

    Consistent individual differences within (animal personality) and across (behavioural syndrome) behaviours became well recognized during the past decade. Nevertheless, our knowledge about the evolutionary and developmental mechanisms behind the phenomena is still incomplete. Here, we explored if risk-taking and exploration were consistent and linked to different ecologically relevant traits in wild-caught adult male European green lizards (Lacerta viridis) and in their 2-3 weeks old laboratory-reared offspring. Both adults and juveniles displayed animal personality, consistency being higher in juveniles. We found correlation between risk-taking and exploration (suggestive of a behavioural syndrome) only in adults. Juveniles were more explorative than adults. Large or ectoparasite-free adult males were more explorative than small or parasitized males. Juvenile females tended to be more risk-taking than males. Behaviour of fathers and their offspring did not correlate. We conclude that European green lizards show high behavioural consistency and age is an important determinant of its strength and links to traits likely affecting fitness.

  6. Four types of interference competition and their impacts on the ecology and evolution of size-structured populations and communities

    Zhang, Lai; Andersen, Ken Haste; Dieckmann, Ulf

    2015-01-01

    -structured communities. Like other types of trait-mediated competition, all four types of interference competition can induce disruptive selection and thus promote initial diversification. Even though foraging interference and reproductive interference are more potent in promoting initial diversification, they catalyze...... the formation of diverse communities with complex trophic structure only at high levels of interference intensity. By contrast, survival interference does so already at intermediate levels, while reproductive interference can only support relatively smaller communities with simpler trophic structure. Taken...

  7. An ecological analysis of food outlet density and prevalence of type II diabetes in South Carolina counties

    AlHasan, Dana M.; Eberth, Jan Marie

    2016-01-01

    Background Studies suggest that the built environment with high numbers of fast food restaurants and convenience stores and low numbers of super stores and grocery stores are related to obesity, type II diabetes mellitus, and other chronic diseases. Since few studies assess these relationships at the county level, we aim to examine fast food restaurant density, convenience store density, super store density, and grocery store density and prevalence of type II diabetes among counties in South ...

  8. Assessments of Drought Impacts on Vegetation in China with the Optimal Time Scales of the Climatic Drought Index.

    Li, Zheng; Zhou, Tao; Zhao, Xiang; Huang, Kaicheng; Gao, Shan; Wu, Hao; Luo, Hui

    2015-07-08

    Drought is expected to increase in frequency and severity due to global warming, and its impacts on vegetation are typically extensively evaluated with climatic drought indices, such as multi-scalar Standardized Precipitation Evapotranspiration Index (SPEI). We analyzed the covariation between the SPEIs of various time scales and the anomalies of the normalized difference vegetation index (NDVI), from which the vegetation type-related optimal time scales were retrieved. The results indicated that the optimal time scales of needle-leaved forest, broadleaf forest and shrubland were between 10 and 12 months, which were considerably longer than the grassland, meadow and cultivated vegetation ones (2 to 4 months). When the optimal vegetation type-related time scales were used, the SPEI could better reflect the vegetation's responses to water conditions, with the correlation coefficients between SPEIs and NDVI anomalies increased by 5.88% to 28.4%. We investigated the spatio-temporal characteristics of drought and quantified the different responses of vegetation growth to drought during the growing season (April-October). The results revealed that the frequency of drought has increased in the 21st century with the drying trend occurring in most of China. These results are useful for ecological assessments and adapting management steps to mitigate the impact of drought on vegetation. They are helpful to employ water resources more efficiently and reduce potential damage to human health caused by water shortages.

  9. Generic index of aquatic vegetation (IVAM) for a rapid assessment of ecological quality of Spanish rivers: taxonomic resolution and application to Castilla-La Mancha region; Indice Generico de Vegetacion Acuatica (IVAM): Propuesta de evaluacion rapida del estado ecologico de los rios ibericos en aplicacion de la Directiva Marco del Agua

    Moreno, J. L.; Navarro, C.; Hera, J. de las

    2005-07-01

    The Water Framework Directive proposes the use of aquatic flora as a valid bio indicator for assessing the ecological status of European rivers. Due to the lack of an aquatic vegetation index for Spanish rivers, we present an index to assess trophic status or eutrophication in rivers and streams. Thus, we calculated tolerance scores and indicator values for tax from nutrient levels. the index is called IVAM (Macroscopic Aquatic Vegetation Index). The index takes into account either macrophyte or microphytes (the latter making up macroscopic growth forms) including briophytes. The IVAM showed the best correlation with nutrients besides other quality indices, indicating a solid tool to assess trophic status or eutrophication. (Author) 15 refs.

  10. General Vegetation

    Earth Data Analysis Center, University of New Mexico — This file contains vector digital data for vegetation groupings in New Mexico at a 1:1,000,000 scale. The source software was ARC/INFO 5.0.1 and the conversion...

  11. Drought-induced vegetation shifts in terrestrial ecosystems: The key role of regeneration dynamics

    Martínez-Vilalta, Jordi; Lloret, Francisco

    2016-09-01

    Ongoing climate change is modifying climatic conditions worldwide, with a trend towards drier conditions in most regions. Vegetation will respond to these changes, eventually adjusting to the new climate. It is unclear, however, how close different ecosystems are to climate-related tipping points and, thus, how dramatic these vegetation changes will be in the short- to mid-term, given the existence of strong stabilizing processes. Here, we review the published evidence for recent drought-induced vegetation shifts worldwide, addressing the following questions: (i) what are the necessary conditions for vegetation shifts to occur? (ii) How much evidence of drought-induced vegetation shifts do we have at present and where are they occurring? (iii) What are the main processes that favor/oppose the occurrence of shifts at different ecological scales? (iv) What are the complications in detecting and attributing drought-induced vegetation shifts? (v) What ecological factors can interact with drought to promote shifts or stability? We propose a demographic framework to classify the likely outcome of instances of drought-induced mortality, based upon the survival of adults of potential replacement species and the regeneration of both formerly dominant affected species and potential replacement species. Out of 35 selected case studies only eight were clearly consistent with the occurrence of a vegetation shift (species or biome shift), whereas three corresponded to self-replacements in which the affected, formerly dominant species was able to regenerate after suffering drought-induced mortality. The other 24 cases were classified as uncertain, either due to lack of information or, more commonly, because the initially affected and potential replacement species all showed similar levels of regeneration after the mortality event. Overall, potential vegetation transitions were consistent with more drought-resistant species replacing less resistant ones. However, almost half (44

  12. Evidence for ecological divergence across a mosaic of soil types in an Amazonian tropical tree: Protium subserratum (Burseraceae).

    Misiewicz, Tracy M; Fine, Paul V A

    2014-05-01

    Soil heterogeneity is an important driver of divergent natural selection in plants. Neotropical forests have the highest tree diversity on earth, and frequently, soil specialist congeners are distributed parapatrically. While the role of edaphic heterogeneity in the origin and maintenance of tropical tree diversity is unknown, it has been posited that natural selection across the patchwork of soils in the Amazon rainforest is important in driving and maintaining tree diversity. We examined genetic and morphological differentiation among populations of the tropical tree Protium subserratum growing parapatrically on the mosaic of white-sand, brown-sand and clay soils found throughout western Amazonia. Nuclear microsatellites and leaf morphology were used to (i) quantify the extent of phenotypic and genetic divergence across habitat types, (ii) assess the importance of natural selection vs. drift in population divergence, (iii) determine the extent of hybridization and introgression across habitat types, (iv) estimate migration rates among populations. We found significant morphological variation correlated with soil type. Higher levels of genetic differentiation and lower migration rates were observed between adjacent populations found on different soil types than between geographically distant populations on the same soil type. PST -FST comparisons indicate a role for natural selection in population divergence among soil types. A small number of hybrids were detected suggesting that gene flow among soil specialist populations may occur at low frequencies. Our results suggest that edaphic specialization has occurred multiple times in P. subserratum and that divergent natural selection across edaphic boundaries may be a general mechanism promoting and maintaining Amazonian tree diversity.

  13. Taking a systems approach to ecological systems

    Grace, James B.

    2015-01-01

    Increasingly, there is interest in a systems-level understanding of ecological problems, which requires the evaluation of more complex, causal hypotheses. In this issue of the Journal of Vegetation Science, Soliveres et al. use structural equation modeling to test a causal network hypothesis about how tree canopies affect understorey communities. Historical analysis suggests structural equation modeling has been under-utilized in ecology.

  14. Investigation of vegetation with multifrequency and multipolarization SAR systems

    Winter, Rudolf; Roth, Achim; Bayer, Thomas

    1990-05-01

    Investigations of vegetation is conducted by synergism of different types of digital image data and models. As a standard application, satellite images are digitally coregistered with existant topographical data and stored in the Geographic Information Systems (GIS). The usefulness of multiparametric SAR (Synthetic Aperture Radar) data for vegetation mapping is discussed. The multifrequency aspects requires precise geocoding. Different application fields with recent results are discussed: forest investigations with SIR (Spaceborne Imaging Radar)-B data in the southern Rhine valley ; extraction of landuse categories in landscape units using two geocoded Seasat-SAR scenes in the area of Bonn; relief effects on image gray values in geocoded Seasat-SAR images; the concept of a remote sensing data base for ecological applications.

  15. Connectivity processes and riparian vegetation of the upper Paraná River, Brazil

    Stevaux, José C.; Corradini, Fabrício A.; Aquino, Samia

    2013-10-01

    In fluvial systems, the relationship between a dominant variable (e.g. flood pulse) and its dependent ones (e.g. riparian vegetation) is called connectivity. This paper analyzes the connectivity elements and processes controlling riparian vegetation for a reach of the upper Paraná River (Brazil) and estimates the future changes in channel-vegetation relationship as a consequence of the managing of a large dam. The studied reach is situated 30 km downstream from the Porto Primavera Dam (construction finished in 1999). Through aerial photography (1:25,000, 1996), RGB-CBERS satellite imagery and a previous field botany survey it was possible to elaborate a map with the five major morpho-vegetation units: 1) Tree-dominated natural levee, 2) Shrubby upper floodplain, 3) Shrub-herbaceous mid floodplain, 4) Grass-herbaceous lower floodplain and 5) Shrub-herbaceous flood runoff channel units. By use of a detailed topographic survey and statistical tools each morpho-vegetation type was analyzed according to its connectivity parameters (frequency, recurrence, permanence, seasonality, potamophase, limnophase and FCQ index) in the pre- and post-dam closure periods of the historical series. Data showed that most of the morpho-vegetation units were predicted to present changes in connectivity parameters values after dam closing and the new regime could affect, in different intensity, the river ecology and particularly the riparian vegetation. The methods used in this study can be useful for dam impact studies in other South American tropical rivers.

  16. Monitoring vegetation responses to drought -- linking Remotely-sensed Drought Indices with Meteorological drought indices

    Wang, H.; Lin, H.; Liu, D.

    2013-12-01

    Abstract: Effectively monitoring vegetation drought is of great significance in ecological conservation and agriculture irrigation at the regional scale. Combining meteorological drought indices with remotely sensed drought indices can improve tracking vegetation dynamic under the threat of drought. This study analyzes the dynamics of spatially-defined Temperature Vegetation Dryness Index (TVDI) and temporally-defined Vegetation Health Index (VHI) from remotely sensed NDVI and LST datasets in the dry spells in Southwest China. We analyzed the correlation between remotely sensed drought indices and meteorological drought index of different time scales. The results show that TVDI was limited by the spatial variations of LST and NDVI, while VHI was limited by the temporal variations of LST and NDVI. Station-based buffering analysis indicates that the extracted remotely sensed drought indices and Standard Precipitation Index (SPI) could reach stable correlation with buffering radius larger than 35 km. Three factors affect the spatiotemporal relationship between remotely sensed drought indices and SPI: i) different vegetation types; ii) the timescale of SPI; and iii) remote sensing data noise. Vegetation responds differently to meteorological drought at various time scales. The correlation between SPI6 and VHI is more significant than that between SPI6 and TVDI. Spatial consistency between VHI and TVDI varies with drought aggravation. In early drought period from October to December, VHI and TVDI show limited consistency due to the low quality of remotely sensed images. The study helps to improve monitoring vegetation drought using both meteorological drought indices and remotely sensed drought indices.

  17. Mapping ecological states in a complex environment

    Steele, C. M.; Bestelmeyer, B.; Burkett, L. M.; Ayers, E.; Romig, K.; Slaughter, A.

    2013-12-01

    analysis provides a platform for classification that more closely resembles human recognition of objects within a remotely sensed image. The analysis presented here compares multiple thematic maps created for test locations on the USDA-ARS Jornada Experimental Range ranch. Three study sites in different pastures, each 300 ha in size, were selected for comparison on the basis of their ecological site type (';Clayey', ';Sandy' and a combination of both) and the degree of complexity of vegetation cover. Thematic maps were produced for each study site using (i) manual interpretation of digital aerial photography (by five independent interpreters); (ii) object-oriented, decision-tree classification of fine and moderate spatial resolution imagery (Quickbird; Landsat Thematic Mapper) and (iii) ground survey. To identify areas of uncertainty, we compared agreement in location, areal extent and class assignation between 5 independently produced, manually-digitized ecological state maps and with the map created from ground survey. Location, areal extent and class assignation of the map produced by object-oriented classification was also assessed with reference to the ground survey map.

  18. Ecological economic benefit in sustainable development

    Jiang Xuemin; Ren Long

    2006-01-01

    From the concept of ecological economic benefit, I put forward the general formula for the benefit of ecological economy and the appraisal methods of the ecological economy, Theory on ecological benefit and economic benefit is the base of the benefits of ecological economy To some extent, the development of ecological economy, theory and practice on eco-agriculture are both the production made from opposition and unify of ecological benefit and economic benefit. This paper discusses the "T" type structure, which will give the theoretical bases for enhancing the ecological and economical benefits.

  19. The soil microbial community composition and soil microbial carbon uptake are more affected by soil type than by different vegetation types (C3 and C4 plants) and seasonal changes

    Griselle Mellado Vazquez, Perla; Lange, Markus; Gleixner, Gerd

    2016-04-01

    This study investigates the influence of different vegetation types (C3 and C4 plants), soil type and seasonal changes on the soil microbial biomass, soil microbial community composition and soil microbial carbon (C) uptake. We collected soil samples in winter (non-growing season) and summer (growing season) in 2012 from an experimental site cropping C3 and C4 plants for 6 years on two different soil types (sandy and clayey). The amount of phospholipid fatty acids (PLFAs) and their compound-specific δ13C values were used to determined microbial biomass and the flow of C from plants to soil microorganisms, respectively. Higher microbial biomass was found in the growing season. The microbial community composition was mainly explained by soil type. Higher amounts of SOC were driving the predominance of G+ bacteria, actinobacteria and cyclic G- bacteria in sandy soils, whereas root biomass was significantly related to the increased proportions of G- bacteria in clayey soils. Plant-derived C in G- bacteria increased significantly in clayey soils in the growing season. This increase was positively and significantly driven by root biomass. Moreover, changes in plant-derived C among microbial groups pointed to specific capabilities of different microbial groups to decompose distinct sources of C. We concluded that soil texture and favorable growth conditions driven by rhizosphere interactions are the most important factors controlling the soil microbial community. Our results demonstrate that a change of C3 plants vs. C4 plants has only a minor effect on the soil microbial community. Thus, such experiments are well suited to investigate soil organic matter dynamics as they allow to trace the C flow from plants into the soil microbial community without changing the community abundance and composition.

  20. 地枫皮营养器官解剖结构特征及其叶片结构的生态适应性%Anatomical Features of Vegetative Organs and Ecological Adaptability of Leaf Structure of Illicium difengpi

    孔德鑫; 李雁群; 梁惠凌; 王满莲; 史艳财; 蒋运生

    2012-01-01

    In order to study the structural characteristic of Illicium difengpi, and the difference of leaf anatomy between leaves from trees which grow in the limestone mountaintop and the open mountainside forest, the paraffin and half thin section technology were used to observe the vegetative organs of Illicium difengpi and the responses of leaf structure in different ecological environments were also evaluated. The results show that in roots, the secondary vascular tissue is well developed and the xylem ray and phloem ray are all obvious. In stem, the storage substance in secondary structure is abundant and has large stone cells group, and the xylem ray and phloem ray are apparent as well, while marrow cells containe a large number of druse and a few of single crystal. In the cross section, the leaf is typically bifacial, and epidermal cells are only in one layer and no stomata is in the upper epidermis. Moreover, there are sclereids scattered in parenchyma cells of main vein. The anatomical features of leaf show that the /. difengpi has the characters of typical xerophytic plants when it grows in naked limestone mountaintop. The cuticle of leaf epidermis cell wall is thicker and the ratio of palisade to spongy tissuesis increased, but the cells of spongy tissue become to be organized loosely rather than tightly, In addition, there are a large number of oil cells distributed in velamen, bark and mesophyll.%为了明确地枫皮的结构特征及其在石灰岩山顶和山腰疏林间两种环境下生长的叶片解剖结构的差异,本研究采用石蜡切片和半薄切片对地枫皮营养器官进行解剖观察并评价了叶片结构对不同生态环境的响应.结果表明:地枫皮根中次生维管组织发达,木射线和韧皮射线明显.老茎的次生构造中,皮层贮藏物质丰富,内有大的石细胞群,韧皮射线和木射线明显;而髓细胞内含有大量晶簇和少量单晶.在叶片横切面观上,叶为异面叶,表皮细胞一层,上表

  1. Desertification Risk Monitoring for North Shaanxi Province, China, Using Normalized Difference Vegetation Index (NDVI)

    2002-01-01

    In this study, the remote sensing is applied to the examination of the relationship between desertification and normalized difference vegetation index (NDVI) in the context of northern Shaanxi Province. This relationship is also examined using spatial analysis methods. A strong negative correlation is found in the largest area desert, indicating that the relationship between desert and NDVI is not a simple linear one and that the correlation coefficient between NDVI and vegetation abundance is significant.The normalized difference vegetation index (NDVI) was compared with other vegetation index-based methodologies. NDVI is a valuable first-cut indicator for such systems, although the analysis and interpretation of its relationship to desertification are complex and also based on the detailed analysis of its reiationship to ecological zone, vegetation type and season. Conclusions thus made would help to upgrade the methodology as an effective tool for early-warning desertification in the northern Shaanxi Province where a drought is a recurring threat. This methodology includes the integration of NDVI with other socio-economic and bio-physical indicators in GIS, the complementation of desert area data with satellite data, and the analysis of the relationship between NDVI and specific climatic zones, for each season and vegetation type.

  2. Riparian vegetation and water yield: A synthesis

    Salemi, Luiz Felippe; Groppo, Juliano Daniel; Trevisan, Rodrigo; Marcos de Moraes, Jorge; de Paula Lima, Walter; Martinelli, Luiz Antonio

    2012-08-01

    SummaryForested riparian zones perform numerous ecosystem functions, including the following: storing and fixing carbon; serving as wildlife habitats and ecological corridors; stabilizing streambanks; providing shade, organic matter, and food for streams and their biota; retaining sediments and filtering chemicals applied on cultivated/agricultural sites on upslope regions of the catchments. In this paper, we report a synthesis of a different feature of this type of vegetation, which is its effect on water yield. By synthesizing results from studies that used (i) the nested catchment and (ii) the paired catchment approaches, we show that riparian forests decrease water yield on a daily to annual basis. In terms of the treated area increases on average were 1.32 ± 0.85 mm day-1 and 483 ± 309 mm yr-1, respectively; n = 9. Similarly, riparian forest plantation or regeneration promoted reduced water yield (on average 1.25 ± 0.34 mm day-1 and 456 ± 125 mm yr-1 on daily and annual basis, respectively, when prorated to the catchment area subjected to treatment; n = 5). Although there are substantially fewer paired catchment studies assessing the effect of this vegetation type compared to classical paired catchment studies that manipulate the entire vegetation of small catchments, our results indicate the same trend. Despite the occurrence of many current restoration programs, measurements of the effect on water yield under natural forest restoration conditions are still lacking. We hope that presenting these gaps will encourage the scientific community to enhance the number of observations in these situations as well as produce more data from tropical regions.

  3. Vegetation of the rock habitats of the Sekhukhuneland Centre of Plan Endemism, South Africa

    S. J. Siebert

    2003-12-01

    Full Text Available A hierarchical classification, description, and ecological and floristic interpretations are presented on the vegetation types of the ultramafic rock habitats of the Sekhukhuneland Centre of Plant Endemism. Relevés were compiled in 100 stratified random plots. A TWINSPAN classification, refined by Braun-Blanquet procedures, revealed 17 plant communities, which are classified into 13 associations belonging to four proposed alliances. Many new syntaxa are ecologically interpreted and described. For each syntaxon, the species richness, endemism and conservation status was determined. Much of the plant community distribution can be ascribed to specific habitat preference. The floristic and habitat information, proposed classification, general description and vegetation key are provided to aid future identification of conservation areas, land use planning and research. An ordination (DECORANA based on floristic data confirmed potential relationships that could exist between the plant communities and associated habitats and environmental gradients.

  4. Vegetated foreshores as coastal protection strategy: Coping with uncertainties and implementation

    Borsje, Bas; Bouma, Tjeerd; De Vries, Mindert; Timmermans, Jos; Vuik, Vincent; Hermans, Leon; Hulscher, Suzanne; Jonkman, Bas

    2014-05-01

    Promising Building with Nature solutions for flood protection, such as vegetated foreshores, inherently have a dynamic nature. Therefore there is a relatively large degree of uncertainty with respect to their contribution to flood protection. This hampers innovation and the implementation of vegetated foreshores in flood risk management worldwide. We aim to develop new methods to assess how, and how much vegetated foreshores can contribute to flood risk reduction. The project will lead to a better understanding of (uncertainties in) the functioning and stability of these ecosystems and the development of novel governance arrangements. This requires integration of knowledge from ecology, biogeomorphology, hydraulic engineering, and governance. By field observations on several sites and flume measurements we will analyse fundamental ecological and physical processes for various types of wetland vegetations. The knowledge obtained will be applied in one implementation case study for a location in the Netherlands where dike reinforcement is needed in the future. This case study integrates fundamental knowledge from all the disciplines. It is used to design governance and implementation arrangements, and to demonstrate how vegetated foreshores can contribute to flood risk reduction. The project will provide the knowledge, methods and tools (e.g. a maptable) required for the design and implementation of vegetated foreshores as a safe, ecologically desirable, and cost effective alternative in flood management. Strong cooperation with end-users from the private sector, government and non-governmental organizations is embedded in the project to enhance the implementation of our findings in practice. In the full-paper, we present a multidisciplinary research agenda how to address the uncertainties hampering application, how to develop probabilistic tools to derive failure chance in legally imposed terms and how to derive at suitable governance arrangements.

  5. Spatial Vegetation Data for Sagamore Hill National Historic Site Vegetation Mapping Project

    National Park Service, Department of the Interior — This shapefile is the final vegetation map of Sagamore Hill National Historic Site that provides local names for vegetation types, as well as crosswalks to the...

  6. Spatial Vegetation Data for Allegheny Portage Railroad National Historic Site Vegetation Mapping Project

    National Park Service, Department of the Interior — Vegetation map of Allegheny Portage Railroad National Historic Site provides local park-specific names for vegetation types, as well as crosswalks to the National...

  7. [Tourism function zoning of Jinyintan Grassland Scenic Area in Qinghai Province based on ecological sensitivity analysis].

    Zhong, Lin-sheng; Tang, Cheng-cai; Guo, Hua

    2010-07-01

    Based on the statistical data of natural ecology and social economy in Jinyintan Grassland Scenic Area in Qinghai Province in 2008, an evaluation index system for the ecological sensitivity of this area was established from the aspects of protected area rank, vegetation type, slope, and land use type. The ecological sensitivity of the sub-areas with higher tourism value and ecological function in the area was evaluated, and the tourism function zoning of these sub-areas was made by the technology of GIS and according to the analysis of eco-environmental characteristics and ecological sensitivity of each sensitive sub-area. It was suggested that the Jinyintan Grassland Scenic Area could be divided into three ecological sensitivity sub-areas (high, moderate, and low), three tourism functional sub-areas (restricted development ecotourism, moderate development ecotourism, and mass tourism), and six tourism functional sub-areas (wetland protection, primitive ecological sightseeing, agriculture and pasture tourism, grassland tourism, town tourism, and rural tourism).

  8. Determining Spatial Parameters of the Ecological Niche of Parus Major (Passeriformes, Paridae on the Base of Remote Sensing Data

    Zimaroeva А. A.

    2016-06-01

    Full Text Available Using factor analysis of ecological niches, we found that Parus major has high marginality to such ecogeographical variables (EGVs, as normalized difference vegetation index, the altitude above sea level, the diffuse insolation, activity of chlorophyll, normalized difference water index. This species is highly specialized in relation to various vegetation indices. Based on the type of habitat preference map, we found that Parus major doesn’t implement all its potential pro-spatial niche. Considering the ecological niche of great tit on different levels of scale, we noticed certain features: first, a list of factors that influence the distribution of great tit significantly altered by changing the scale, secondly, the factors that play a significant role in spreading Parus major on level of total consideration losing their weight and relevance on closer inspection (when the scale down; third, although specialization of great tits changes with the scale of consideration but Parus major mostly specialized by vegetation index.

  9. Historical and contemporary geographic data reveal complex spatial and temporal responses of vegetation to climate and land stewardship

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

    2013-01-01

    Vegetation and land-cover changes are not always directional but follow complex trajectories over space and time, driven by changing anthropogenic and abiotic conditions. We present a multi-observational approach to land-change analysis that addresses the complex geographic and temporal variability of vegetation changes related to climate and land use. Using land-ownership 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. In contrast to many reported vegetation changes, notably shrub encroachment in desert grasslands, we found an overall increase in grassland area and decline of xeroriparian and riparian vegetation. These observed change patterns were neither temporally directional nor spatially uniform over the landscape. Historical data suggest that long-term vegetation changes coincide with broad climate fluctuations while fine-scale patterns are determined by land-management practices. In some cases, restoration and active management appear to weaken the effects of climate on vegetation; therefore, if land managers in this region act in accord with on-going directional changes, the current drought and associated ecological reorganization may provide an opportunity to achieve desired restoration endpoints.

  10. Assessments of Drought Impacts on Vegetation in China with the Optimal Time Scales of the Climatic Drought Index

    Zheng Li

    2015-07-01

    Full Text Available Drought is expected to increase in frequency and severity due to global warming, and its impacts on vegetation are typically extensively evaluated with climatic drought indices, such as multi-scalar Standardized Precipitation Evapotranspiration Index (SPEI. We analyzed the covariation between the SPEIs of various time scales and the anomalies of the normalized difference vegetation index (NDVI, from which the vegetation type-related optimal time scales were retrieved. The results indicated that the optimal time scales of needle-leaved forest, broadleaf forest and shrubland were between 10 and 12 months, which were considerably longer than the grassland, meadow and cultivated vegetation ones (2 to 4 months. When the optimal vegetation type-related time scales were used, the SPEI could better reflect the vegetation’s responses to water conditions, with the correlation coefficients between SPEIs and NDVI anomalies increased by 5.88% to 28.4%. We investigated the spatio-temporal characteristics of drought and quantified the different responses of vegetation growth to drought during the growing season (April–October. The results revealed that the frequency of drought has increased in the 21st century with the drying trend occurring in most of China. These results are useful for ecological assessments and adapting management steps to mitigate the impact of drought on vegetation. They are helpful to employ water resources more efficiently and reduce potential damage to human health caused by water shortages.

  11. Classification and ordination of understory vegetation using multivariate techniques in the Pinus wallichiana forests of Swat Valley, northern Pakistan

    Rahman, Inayat Ur; Khan, Nasrullah; Ali, Kishwar

    2017-04-01

    An understory vegetation survey of the Pinus wallichiana-dominated temperate forests of Swat District was carried out to inspect the structure, composition and ecological associations of the forest vegetation. A quadrat method of sampling was used to record the floristic and phytosociological data necessary for the analysis using 300 quadrats of 10 × 10 m each. Some vegetation parameters viz. frequency and density for trees (overstory vegetation) as well as for the understory vegetation were recorded. The results revealed that in total, 92 species belonging to 77 different genera and 45 families existed in the area. The largest families were Asteraceae, Rosaceae and Lamiaceae with 12, ten and nine species, respectively. Ward's agglomerative cluster analysis for tree species resulted in three floristically and ecologically distinct community types along different topographic and soil variables. Importance value indices (IVI) were also calculated for understory vegetation and were subjected to ordination techniques, i.e. canonical correspondence analysis (CCA) and detrended correspondence analysis (DCA). DCA bi-plots for stands show that most of the stands were scattered around the centre of the DCA bi-plot, identified by two slightly scattered clusters. DCA for species bi-plot clearly identified three clusters of species revealing three types of understory communities in the study area. Results of the CCA were somewhat different from the DCA showing the impact of environmental variables on the understory species. CCA results reveal that three environmental variables, i.e. altitude, slope and P (mg/kg), have a strong influence on distribution of stands and species. Impact of tree species on the understory vegetation was also tested by CCA which showed that four tree species, i.e. P. wallichiana A.B. Jackson, Juglans regia Linn., Quercus dilatata Lindl. ex Royle and Cedrus deodara (Roxb. ex Lamb.) G. Don, have strong influences on associated understory vegetation. It

  12. Ecological recovery in an Arctic delta following widespread saline incursion.

    Lantz, Trevor C; Kokelj, Steve V; Fraser, Robert H

    2015-01-01

    Arctic ecosystems are vulnerable to the combined effects of climate change and a range of other anthropogenic perturbations. Predicting the cumulative impact of these stressors requires an improved understanding of the factors affecting ecological resilience. In September of 1999, a severe storm surge in the Mackenzie Delta flooded alluvial surfaces up to 30 km inland from the coast with saline waters, driving environmental impacts unprecedented in the last millennium. In this study we combined field monitoring of permanent sampling plots with an analysis of the Landsat archive (1986-2011) to explore the factors affecting the recovery of ecosystems to this disturbance. Soil salinization following the 1999 storm caused the abrupt dieback of more than 30,000 ha of tundra vegetation. Vegetation cover and soil chemistry show that recovery is occurring, but the rate and spatial extent are strongly dependent on vegetation type, with graminoid- and upright shrub-dominated areas showing recovery after a decade, but dwarf shrub tundra exhibiting little to no recovery over this period. Our analyses suggest that recovery from salinization has been strongly influenced by vegetation type and the frequency of freshwater flooding following the storm. With increased ocean storm activity, rising sea levels, and reduced sea ice cover, Arctic coastal ecosystems will be more likely to experience similar disturbances in the future, highlighting the importance of combining field sampling with regional-scale remote sensing in efforts to detect, understand, and anticipate environmental change.

  13. Ecological restoration and soil improvement performance of the seabuckthorn flexible dam in the Pisha Sandstone area of Northwestern China

    Yang, F. S.; Cao, M. M.; Li, H. E.; Wang, X. H.; Bi, C. F.

    2014-09-01

    Soil erosion of the Pisha Sandstone area of Loess Plateau is extremely severe in China. The Pisha Sandstone is very hard when it is dry, while it is very frail when wet. The seabuckthorn flexible dam (SFD), a type of ecological engineering, was proposed to control soil erosion and meliorate soil within the Pisha Sandstone area. To assess its effectiveness and the ecological restoration and soil improvement performance, a field experiment was conducted in this area. We found the strong sediment retention capacity of the SFD is the basis of using it to restore the ecosystem. We compared some certain ecological factors and soil quality between a gully with the SFD and a gully without the SFD, including soil moisture, soil organic matter (SOM), soil nutrients (including Ammonia Nitrogen, available phosphorus and Potassium), vegetation coverage and biodiversity. The results showed that the SFD exhibits excellent performance for ecological restoration and soil improvement of this area. The results are as follows: (i) by the sediment retention action, the deposition commonly occurred in the SFD gully, and the deposition patterns are obviously different from upper to lower gully, (ii) more surprisingly, unlike trees or other shrubs, the seabuckthorn has good horizontal extending capacity by its root system, (iii) soil moisture, SOM, soil nutrients, vegetation coverage and biodiversity in the vegetated gully with the SFD are all markedly increased. The results showed the SFD is both effective and novel biological measure for ecological restoration and soil improvement within the Pisha Sandstone area.

  14. Post-fire vegetation dynamics in Portugal

    Gouveia, C.; Dacamara, C. C.; Trigo, R. M.

    2009-04-01

    analysed for some selected areas and a regression model of post-fire recovery was fitted to the recorded values of NDVI. The model allowed characterising the dynamics of the regeneration process. It was found that recovery rates depend on geographical location, fire intensity/severity and type of vegetation cover. Díaz-Delgado, R., Salvador, R. and Pons, X., 1998: Monitoring of plant community regeneration after fire by remote sensing. In L. Traboud (Ed.), Fire management and landscape ecology (pp. 315-324). International Association of Wildland Fire, Fairfield, WA. Pausas, G.J. and Vallejo, V.R., 1999: The role of fire in European Mediterranean Ecosystems. In: E. Chuvieco (Ed.), Remote sensing of large wildfires in the European Mediterranean basin (pp. 3-16). Springer-Verlag. Trigo R.M., Pereira J.M.C., Pereira M.G., Mota B., Calado M.T., DaCamara C.C., Santo F.E., 2006: Atmospheric conditions associated with the exceptional fire season of 2003 in Portugal. International Journal of Climatology 26 (13): 1741-1757 NOV 15 2006.

  15. 石羊河上游林区景观空间邻接特征及生态安全分析%Spatial neighboring characteristics among forest landscape types patches on the upper reaches of Shiyang River Basin and its ecological security

    汤萃文; 张忠明; 苏研科; 郭明; 杨莎莎; 王天强; 杨啸林

    2013-01-01

    在干旱区山地,荒地斑块特征可反映植被的破碎化及退化状况,农田斑块特征可反映自然植被景观受农田开垦的威胁程度,而其它景观类型与这两种类型斑块的邻接特征可间接反映这些类型潜在的植被退化风险大小或受农田开垦的威胁程度.以Landsat/TM及林相图作为数据源,在桌面GIS下解译出石羊河上游的哈溪林区各景观类型,计算了各景观类型与荒地和农田的空间邻接长度和数目比例,并利用缓冲区分析方法计算了荒地和农田对各景观的影响面积.在此基础上通过计算各类型植被退化风险大小和受农田开垦的威胁程度,定量分析了研究区各景观类型的生态安全性.结果表明:灌丛和草地与荒地的邻接边长和数目较大,由放牧活动引起的植被破碎化和退化的风险较大,而乔木林种与农田的邻接长度、数目较大,受农田开垦的威胁较为严重;景观整体植被退化的风险(0.28)高于受农田威胁程度(0.11);各类型植被退化风险值的差别不明显,但灌丛草地相对较高,而各乔木林种受农田开垦的威胁程度明显高于灌丛和草地;基于景观类型空间邻接的生态安全评价分析可以初步反映干旱区山地景观受人类活动影响的威胁程度.%There is highly significant to estimate the ecological security of the forest landscape ecosystem in the upper reaches of Shiyang River basin which has become the typical ecological degeneration region in arid inland river basin in China recently. In the arid mountains area, the patches characteristics of wasteland can reflect the state of degeneration of vegetation, and the patches characteristic of farmland can reflect the threatening degree of natural vegetation damaged by farmland reclamation. So the magnitudes of potential risk of vegetation degeneration and the threatening degree of farmland reclamation of the forest landscape types should be indicated by

  16. Vegetation - Carrizo Plain ER, 2005 - 2008 [ds561

    California Department of Resources — The Vegetation Map of the Carrizo Plain Ecological Reserve, San Luis Obispo County, California was created by the California Department of Fish and Game (DFG)...

  17. Avalanche ecology and large magnitude avalanche events: Glacier National Park, Montana, USA

    Fagre, Daniel B.; Peitzsch, Erich H.

    2010-01-01

    Large magnitude snow avalanches play an important role ecologically in terms of wildlife habitat, vegetation diversity, and sediment transport within a watershed. Ecological effects from these infrequent avalanches can last for decades. Understanding the frequency of such large magnitude avalanches is also critical to avalanche forecasting for the Going-to-the-Sun Road (GTSR). In January 2009, a large magnitude avalanche cycle occurred in and around Glacier National Park, Montana. The study site is the Little Granite avalanche path located along the GTSR. The study is designed to quantify change in vegetative cover immediately after a large magnitude event and document ecological response over a multi-year period. GPS field mapping was completed to determine the redefined perimeter of the avalanche path. Vegetation was inventoried using modified U.S. Forest Service Forest Inventory and Analysis plots, cross sections were taken from over 100 dead trees throughout the avalanche path, and an avalanche chronology was developed. Initial results indicate that the perimeter of this path was expanded by 30%. The avalanche travelled approximately 1200 vertical meters and 3 linear kilometers. Stands of large conifers as old as 150 years were decimated by the avalanche, causing a shift in dominant vegetation types in many parts of the avalanche path. Woody debris is a major ground cover up to 3 m in depth on lower portions of the avalanche path and will likely affect tree regrowth. Monitoring and measuring the post-avalanche vegetation recovery of this particular avalanche path provides a unique dataset for determining the ecological role of avalanches in mountain landscapes.

  18. Variation in soil enzyme activity as a function of vegetation amount, type, and spatial structure in fire-prone Mediterranean shrublands

    Garcia Mayor, Angeles; Goirán, Silvana B.; Vallejo, Ramón V.; Bautista, Susana

    2016-01-01

    Fire-prone Mediterranean shrublands may be seriously threatened by land degradation due to progressive opening of the vegetation cover driven by increasing drought and fire recurrence. However, information about the consequences of this opening process for critical ecosystem functions is scant. I

  19. ECOLOGICAL SERIES OF SOIL ANIMALS IN DARLIDAI MOUNTAIN

    2002-01-01

    The ecological series of soil animals under the broad-leaved and pine mixed forest in Darlidai Mountainwas studied. Seven sample plots were selected according to different altitude gradients, which belong to different vegeta-tion types. By investigating and analyzing soil animals in every sample plot it is found that there are 45 groups and 1956individuals, which are involved in 3 phylums, 7 classes, 16 orders, respectively. The altitude is a key factor which af-fects ecological series of soil animals. Both the groups and individuals of soil animals increase with altitude increasingunder certain conditions, which contrastes with ordinary cases, resulting from special micro-climate in studied area. Thegroups and individuls of soil animals are the most under the broad-leaved and pine forest on the top of the mountain, andthe least under Picea-Abies forest in the foot of the mountain.

  20. Vegetation impact on the thermal regimes of the active layer and near-surface permafrost in the Greater Hinggan Mountains, Northeastern China

    XiaoLi Chang; ShaoPeng Yu; HuiJun Jin; YanLin Zhang

    2014-01-01

    The ground temperature and active layer are greatly influenced by vegetation in the Greater Hinggan Mountains in Northeastern China. However, vegetation, as a complex system, is difficult to separate the influence of its different components on the ground thermal regime. In this paper, four vegetation types, including a Larix dahurica-Ledum palustre var. dilatatum-Bryum forest (P1), a L. dahurica-Betula fruticosa forest (P2), a L. dahurica-Carex tato forest (P3) in the China Forest Ecological Research Network Station in Genhe, and a Carex tato swamp (P4) at the permafrost observation site in Yitulihe, have been selected to study and compare their seasonal and annual influence on the ground thermal regime. Results show that the vegetation insulates the ground resulting in a relatively high ground temperature variability in the Carex tato swamp where there are no tree stands and shrubs when compared with three forested vegetation types present in the area. Vegetation thickness, structure, and coverage are the most important factors that determine the insulating prop-erties of the vegetation. In particular, the growth of ground cover, its water-holding capacity and ability to intercept snow exert a significant effect on the degree of insulation of the soil under the same vegetation.

  1. Mollusc and plant assemblages controlled by different ecological gradients at Eastern European fens

    Schenková, Veronika; Horsák, Michal; Hájek, Michal; Plesková, Zuzana; Dítě, Daniel; Pawlikowski, Paweł

    2014-04-01

    Ecological patterns of mollusc assemblages and vegetation in relation to water chemistry, water regime, nutrient availability and climate were studied in eastern Polish lowland fens. Our goal was to examine if major compositional changes differ for molluscs and vegetation under the joint influence of multiple ecological gradients. Altogether 32 fen sites were investigated in 2010-2011, and analyzed using metric multidimensional scaling, cluster analysis and generalized additive models. Two major gradients driving the differences in mollusc species composition were revealed. The main direction of compositional changes was associated with the water table gradient, governing a species turnover from inundated and strongly water-logged sites occupied mostly by aquatic mollusc species, to moderately wet sites with the predominance of fen and meadow species. The second most important gradient for molluscs was that of mineral richness. For vegetation, three major gradients explained the changes in species composition. The highest importance was assigned to the nitrogen-to-phosphorus availability gradient (defined as a shift from N-limited to P-limited vegetation), followed by the water table gradient, and the mineral richness gradient. Our results demonstrate that the impact of mineral richness gradient, which has been often reported as the major determinant of compositional changes of fen molluscs and vegetation, can be exceeded by other ecological gradients of comparable variation. We also document for the first time that the main species turnover of fen vegetation is not accompanied by the analogous change in species composition of mollusc assemblages, due to a different sensitivity of these taxa to particular environmental factors (i.e. water level dynamics and type of nutrient limitation).

  2. Ecological implications of behavioural syndromes.

    Sih, Andrew; Cote, Julien; Evans, Mara; Fogarty, Sean; Pruitt, Jonathan

    2012-03-01

    Interspecific trait variation has long served as a conceptual foundation for our understanding of ecological patterns and dynamics. In particular, ecologists recognise the important role that animal behaviour plays in shaping ecological processes. An emerging area of interest in animal behaviour, the study of behavioural syndromes (animal personalities) considers how limited behavioural plasticity, as well as behavioural correlations affects an individual's fitness in diverse ecological contexts. In this article we explore how insights from the concept and study of behavioural syndromes provide fresh understanding of major issues in population ecology. We identify several general mechanisms for how population ecology phenomena can be influenced by a species or population's average behavioural type, by within-species variation in behavioural type, or by behavioural correlations across time or across ecological contexts. We note, in particular, the importance of behavioural type-dependent dispersal in spatial ecology. We then review recent literature and provide new syntheses for how these general mechanisms produce novel insights on five major issues in population ecology: (1) limits to species' distribution and abundance; (2) species interactions; (3) population dynamics; (4) relative responses to human-induced rapid environmental change; and (5) ecological invasions.

  3. Interactions between Climate, Land Use and Vegetation Fire Occurrences in El Salvador

    Dolors Armenteras

    2016-02-01

    Full Text Available Vegetation burning is a global environmental threat that results in local ecological, economic and social impacts but also has large-scale implications for global change. The burning is usually a result of interacting factors such as climate, land use and vegetation type. Despite its importance as a factor shaping ecological, economic and social processes, countries highly vulnerable to climate change in Central America, such as El Salvador, lack an assessment of this complex relationship. In this study we rely on remotely sensed measures of the Normalized Vegetation Difference Index (NDVI and thermal anomaly detections by the Moderate Resolution Imaging Spectroradiometer (MODIS sensor to identify vegetation cover changes and fire occurrences. We also use land use data and rainfall observations derived from the Tropical Rainfall Measuring Mission (TRMM data to determine the spatial and temporal variability and interactions of these factors. Our results indicate a highly marked seasonality of fire occurrence linked to the climatic variability with a peak of fire occurrences in 2004 and 2013. Low vegetation indices occurred in March–April, around two months after the driest period of the year (December–February, corresponding to months with high detection of fires. Spatially, 65.6% of the fires were recurrent and clustered in agriculture/cropland areas and within 1 km of roads (70% and only a 4.7% of fires detected were associated with forests. Remaining forests in El Salvador deserve more attention due to underestimated consequences of forest fires. The identification of these clear patterns can be used as a baseline to better shape management of fire regimes and support decision making in this country. Recommendations resulting from this work include focusing on fire risk models and agriculture fires and long-term ecological and economic consequences of those. Furthermore, El Salvador will need to include agricultural fires in the

  4. Ecological Modernization

    Mol, A.P.J.

    2006-01-01

    The Encyclopedia of Globalization provides a thorough understanding of the theoretical underpinnings of globalization as well as the various historical and analytical interpretations. Consisting of over 400 entries, coverage includes key cultural, ecological, economic, geographical, historical, poli

  5. Cognitive ecology.

    Hutchins, Edwin

    2010-10-01

    Cognitive ecology is the study of cognitive phenomena in context. In particular, it points to the web of mutual dependence among the elements of a cognitive ecosystem. At least three fields were taking a deeply ecological approach to cognition 30 years ago: Gibson's ecological psychology, Bateson's ecology of mind, and Soviet cultural-historical activity theory. The ideas developed in those projects have now found a place in modern views of embodied, situated, distributed cognition. As cognitive theory continues to shift from units of analysis defined by inherent properties of the elements to units defined in terms of dynamic patterns of correlation across elements, the study of cognitive ecosystems will become an increasingly important part of cognitive science.

  6. Community Ecology

    1988-01-01

    This book presents the proceedings of a workshop on community ecology organized at Davis, in April, 1986, sponsored by the Sloan Foundation. There have been several recent symposia on community ecology (Strong et. al., 1984, Diamond and Case, 1987) which have covered a wide range of topics. The goal of the workshop at Davis was more narrow: to explore the role of scale in developing a theoretical approach to understanding communities. There are a number of aspects of scale that enter into attempts to understand ecological communities. One of the most basic is organizational scale. Should community ecology proceed by building up from population biology? This question and its ramifications are stressed throughout the book and explored in the first chapter by Simon Levin. Notions of scale have long been important in understanding physical systems. Thus, in understanding the interactions of organisms with their physical environment, questions of scale become paramount. These more physical questions illustrate the...

  7. 农村金融生态环境与新型农村金融机构脆弱性%The Fragility of Rural Financial Ecological Environment and New-type Rural Financial Institutions' Based on SEM Analysis

    何颖媛

    2013-01-01

    农村金融生态环境是新型农村金融机构生存和发展的环境基础.为了深入揭示农村金融生态环境对新型农村金融机构脆弱性的影响程度,在分析农村金融生态环境属性构成基础上,构建了农村金融生态环境与新型农村金融机构脆弱性的关系模型,并在问卷调查基础上运用结构方程模型进行实证检验,研究结果表明:除了农村法律环境的影响假设未得到支持外,农村经济环境、农村金融环境、农村政策环境和农村信用环境在降低新型农村金融机构脆弱性方面有显著正向影响.%Rural financial ecological environment provides the basis for the existence and development of new-type rural financial institutions. In order to reveal how much the rural financial ecological environment has influenced the fragility of new-type rural financial institutions this paper, based on an analysis of the components of rural financial ecological environment, constructs a relation model between the rural financial ecological environment and the new-type rural financial Institutions' fragility. SEM is used to analyze the questionnaires. The result proves that rural financial ecological environment consists of five parts: except rural legal environment, rural economic environment, rural financial environment, rural policy environment, rural legal environment and rural credit environment all have a significant positive effect on New-type rural financial Institutions' fragility.

  8. The mountain vegetation of South Peru

    Montesinos-Tubée, D.B.

    2016-01-01

    THE MOUNTAIN VEGETATION OF SOUTH PERU: SYNTAXONOMY, ECOLOGY, PHYTOGEOGRAPHY AND CONSERVATION This thesis presents an overview and revision of plant communities from xerophytic and mountain landscapes in the dry Andes of South Peru. The revision is based on comparison of the collecte

  9. Studying the effect of elevation and edaphic variables on vegetation composition in Khezrabad rangelands using principal component analysis (PCA

    Ruhollah TAGHIZADEH MEHRJARDI

    2009-11-01

    Full Text Available A major scientific challenge in plant ecology is to identify and quantify the strength of environmental factors that are responsible for the distribution and abundance of plant species within and among ecosystems. Hence, this study is focused on relation between plant communities and environmental variables in Khezrabad region of Iran. Based on field surveys, eight vegetation types including Artemisia sieberi-Acantholimon erinaceum, Artemisia sieberi-Hertia angustifolia, Artemisia sieberi-Launea acanthodes, Artemisia sieberi-Salsola tomentosa, Artemisia sieberi-Zygophyllum atriplicoides, Artemisia aucheri-Astrgalus albispinus, Artemisia sieberi-Fortuynia bungei, Haloxylon aphyllum were identified. With respecting to the present variance between vegetation and environmental factors, four samples were established in each vegetation type in 0–30 cm depth. The studied soil variables affecting plant communities were texture, EC, pH, Na+, k+, Cl-, Ca2+, Mg2+, SP, O.M, CaCO3, HCO3 - and CEC. Among the topographic conditions, elevation was recorded in sampling regions as well. Data matrix of environmental factors and vegetation type was made using the windows (ver. 4.17 of PC-ORD. Results according to PCA showed that in the study area, among different environmental factors, the distribution of vegetation types was most strongly correlated with some agents such as soil texture, salinity and sodicity. In fact, soil texture controls distribution of plant species by affecting moisture availability, ventilation and distribution of plant roots. Beside, soil salinity and sodicity because of habitat condition, plant ecological needs and tolerance range can have negative affect on plant diversity. In addition, results indicated that increasing of elevation had negative effect on plant distribution. However, soil characteristics have more influence on vegetation separation than to the elevation in this study.

  10. An Evaluation of the Romanian Fruits and Vegetables Producers Access to Different Types of Common Agricultural Policy Instruments. Is there Any Real Consistency with the Policy Objectives?

    Nicu MARCU

    2015-04-01

    Full Text Available Fruits and vegetables sectors are considered to be strategic in the European Union due to their contribution to a better human health. Among others positive effects, their intake increase reduce mortality and obesity, assuring in the same time harmonised development for young children. The present study thus focused to reveal the consistency of the measure implemented in the Common Agricultural Policy to support fruits and vegetables production in Romania in liaison with the policy objectives. The country is one of the main ten important European producers of horticultural products in terms of production volumes and acreage. Results showed that over the last seven years (2007-2014, the sectorial production drawbacks have not been ameliorated very much. Both sectors are dominated by small-size farms that can produce only seasonally and mainly for short-market chains. In the same time, the greenhouses area shrink to levels that made the country extremely dependent to imports especially for tomatoes. The analysis of the pillar one payments schemes revealed that the fruits and vegetables producers could have access to only one payment that was half from European averages. Moreover, almost half of the producers had low sizes that left them outside the eligible criteria. The measures designed for the second pillar also penalized producers through the selection criteria. These results showed that for Romania there was not a real consistency between the actual policy measures and the objectives assumed by policy makers. The future measures (2014-2020 seem to correct these negative findings being better tailored to the situation of the local fruits and vegetables producers.

  11. SRS ecology: Environmental information document

    Wike, L.D.; Shipley, R.W.; Bowers, J.A. [and others

    1993-09-01

    The purpose of this Document is to provide a source of ecological information based on the exiting knowledge gained from research conducted at the Savannah River Site. This document provides a summary and synthesis of ecological research in the three main ecosystem types found at SRS and information on the threatened and endangered species residing there.

  12. Empirical Analysis of the Vegetable Industry in Hebei Province

    2012-01-01

    We first introduce the status quo of the development of vegetable industry in Hebei Province,and then conduct empirical analysis of the development of vegetable industry in Hebei Province.Further,we analyze the development advantage of the vegetable industry in Hebei Province using SAI(Scale Advantage Indices) and SCA(Symmetric Comparative Advantage),drawing the conclusion that the vegetable industry in Hebei Province has much room for development;at the same time,we analyze the factors influencing vegetable consumption of residents in Hebei Province through the regression model,drawing the conclusion that the vegetable consumer price index is the main factor affecting the consumption.Finally we make recommendations for the development of vegetable industry in Hebei Province as follows:increasing financial input,promoting policy guarantee capacity;implementing brand strategy,promoting the competitiveness of products;improving the ecological environment,promoting industrialization of pollution-free vegetables.

  13. A Case Study on a Trial Site in Western Austria to Assess Benefits of Railway Lineside Vegetation

    Hoerbinger, Stephan; Obriejetan, Michael

    2016-04-01

    Lineside vegetation along railways can provide a wide range of ecosystem services and benefits. At the same time, there are several specific demands on the vegetation systems ensuring maintenance of highest standards of safety and operational performance. As a first step of the study, these demands on lineside vegetation but also their potentials for both rail specific internal and external benefits were summarized. For further analyses a case study was performed. A trial site, located in Austriás western federal state of Vorarlberg, was selected. The overall trial corridor was 22 km long and offered a large diversity in geomorphology, embankment types and surrounding land cover. A GIS-based classification of location types was conducted by using available open source geodata. Additionally, images, taken every fifty meters by a camera, mounted on a locomotive, supported the classification process. Following parameter were assessed: type of the track body, geomorphology, site conditions, technical facilities and surrounding land cover. Along railway infrastructure facilities, ecosystem services, provided by the lineside vegetation, are closely associated with improvement of the stability and resilience of embankments and cuttings. At the same time, specific criteria that must be fulfilled at every location type. These are safety and technical issues, such as keeping the railway clearance profile, economical issues respectively avoiding additional maintenance costs by strong plant growth. Supplementary ecosystem services are strongly related to the position in the landscape and the surrounding land cover. Along urban structures, that can be noise- or sight protection, provided by the lineside vegetation. On location types along agricultural land, lineside vegetation can provide ecological corridors or enhance the landscape structure. In this context, ecosystem services were derived to the previously assigned location types. The result of the case study is a GIS

  14. Mediterranean Biomes: Evolution of their Vegetation, Floras and Climate

    Rundel, Philip W.; Arroyo, Mary T.K.; Cowling, R.M.; Keeley, J. E.; Lamont, B.B.; Vargas, Pablo

    2016-01-01

    Mediterranean-type ecosystems (MTEs) possess the highest levels of plant species richness in the world outside of the wet tropics. Sclerophyll vegetation similar to today’s mediterranean-type shrublands was already present on oligotrophic soils in the wet and humid climate of the Cretaceous, with fire-adapted Paleogene lineages in southwestern Australia and the Cape Region. The novel MTC seasonality present since the mid-Miocene has allowed colonization of MTEs from a regional species pool with associated diversification. Fire persistence has been a primary driving factor for speciation in four of the five regions. Understanding the regional patterns of plant species diversity among the MTEs involves complex interactions of geologic and climatic histories for each region as well as ecological factors that have promoted diversification in the Neogene and Quaternary. A critical element of species richness for many MTE lineages has been their ability to speciate and persist at fine spatial scales, with low rates of extinction.

  15. A regional dynamic vegetation-climate model for Central America

    Snell, R. S.; Cowling, S. A.; Smith, B.

    2009-12-01

    Global vegetation models simulate the distribution of vegetation as a function of climate. Dynamic global vegetation models (DGVMs) are also able to simulate the vegetation shifts in response to climate change, which makes them particularly useful for addressing questions about past and future climate scenarios. However, DGVMs have been criticized for using generic plant functional types (PFTs) and running the models at a coarse grid cell resolution. Regional dynamic vegetation models are able to simulate important landscape variation, since they use a finer resolution and specific PFTs for their region. Regional studies have typically focused on boreal or temperate ecosystems in North America and Europe. We will be presenting the results of applying a dynamic regional vegetation-climate model (LPJ-GUESS) for Central America. Initially, the model was run with the described global PFTs. However, several biomes were very poorly represented. Two PFTs were added: a Tropical Needleleaf Evergreen Tree to improve the simulation of the Mixed Pine-Oak biome, and a Desert Shrub to capture the Xeric Shrublands. The overall distribution of biomes was visually similar, however the Kappa statistic indicated a poor agreement with the potential biome map (overall Kappa = 0.301). The Kappa statistic did improve as we aggregated cell sizes and simplified the biomes (overall Kappa = 0.728). Compared to remote sensing data, the model showed a strong correlation with total LAI (r = 0.75). The poor Kappa statistic is likely due to a combination of factors. The way in which biomes are defined by the author can have a large influence on the level of agreement between simulated and potential vegetation. The Kappa statistic is also limited to comparing individual grid cells and thus, cannot detect overall patterns. Examining those areas which are poorly represented will help to identify future work and improve the representation of vegetation in these ecological models. In particular, the

  16. Audubon vegetation monitoring

    US Fish and Wildlife Service, Department of the Interior — This document is the summary and the analysis of vegetative data for the Audubon Refuge from NPWRC. The data included measurements of vegetation density, vegetation...

  17. Is New Zealand vegetation really 'problematic'? Dansereau's puzzles revisited.

    Wilson, J Bastow; Lee, William G

    2012-05-01

    Over four decades ago, Pierre Dansereau, the noted North American ecologist, proposed six features of New Zealand vegetation as being problematic or unusual in a global context. We examine his propositions in the light of current ecological knowledge to determine whether or not these can still be considered unusual characteristics of New Zealand vegetation. (1) 'Climatic change is still progressing' resulting in disequilibrium between species' distributions and the present climate. New data and methods of analysis now available have removed the impression that Dansereau gained of imprecise zonation, unclear vegetation/climate relations and missing vegetation types. Communities cited as having regeneration failure can now be seen as even-aged stands that developed after major disturbance, although there are other, also non-climatic, explanations. However, the cause of the Westland 'Nothofagus gap' has become more, rather than less, controversial. (2) 'Continuity of community composition defies classification' and 'Very few New Zealand associations have faithful species' are correct observations, but perhaps equally true of vegetation elsewhere. Dansereau's assertion of low species richness in New Zealand is not supported by the comparative data available. (3) 'Lack of intolerant [i.e. mid-seral] trees …' is not evident with newer information. The order of species in succession, seen as unclear by Dansereau, has been determined by a range of approaches, largely confirming each other. (4) 'Discrepancies of form and function …' in divaricate shrubs and widespread heteroblasty are still controversial, with many more explanations. Several abiotic explanations have failed to stand up to investigation. Explanations in terms of herbivory have been well supported, although the extinction of the large avian herbivores makes certainty impossible. (5) 'Incidence of hybridization …' remains problematic. We do not know whether the incidence is unusually high, as Dansereau

  18. The marsh vegetation of Kleinmond Lagoon

    M. O'Callaghan

    1994-12-01

    Full Text Available The vegetation of Kleinmond Lagoon suggests that this system is in transition from an estuary to a coastal lake. Two major types of vegetation were recognized, one which is subjected to soil and water conditions of marine origin and the other which is subjected to conditions of terrestrial origin. These vegetation types are discussed and compared to the vegetation of other estuarine systems. Artificial manipulations of the mouth seem to have resulted in sediment deposition and a freshening of the system. These unseasonable manipulations also threaten the continued existence of a number of species in the system.

  19. Top-down vs. bottom-up control on vegetation composition in a tidal marsh depends on scale.

    Elschot, Kelly; Vermeulen, Anke; Vandenbruwaene, Wouter; Bakker, Jan P; Bouma, Tjeerd J; Stahl, Julia; Castelijns, Henk; Temmerman, Stijn

    2017-01-01

    The relative impact of top-down control by herbivores and bottom-up control by environmental conditions on vegetation is a subject of debate in ecology. In this study, we hypothesize that top-down control by goose foraging and bottom-up control by sediment accretion on vegetation composition within an ecosystem can co-occur but operate at different spatial and temporal scales. We used a highly dynamic marsh system with a large population of the Greylag goose (Anser anser) to investigate the potential importance of spatial and temporal scales on these processes. At the local scale, Greylag geese grub for below-ground storage organs of the vegetation, thereby creating bare patches of a few square metres within the marsh vegetation. In our study, such activities by Greylag geese allowed them to exert top-down control by setting back vegetation succession. However, we found that the patches reverted back to the initial vegetation type within 12 years. At large spatial (i.e. several square kilometres) and temporal scales (i.e. decades), high rates of sediment accretion surpassing the rate of local sea-level rise were found to drive long-term vegetation succession and increased cover of several climax vegetation types. In summary, we conclude that the vegetation composition within this tidal marsh was primarily controlled by the bottom-up factor of sediment accretion, which operates at large spatial as well as temporal scales. Top-down control exerted by herbivores was found to be a secondary process and operated at much smaller spatial and temporal scales.

  20. Economic and ecological outcomes of flexible biodiversity offset systems.

    Habib, Thomas J; Farr, Daniel R; Schneider, Richard R; Boutin, Stan

    2013-12-01

    The commonly expressed goal of biodiversity offsets is to achieve no net loss of specific biological features affected by development. However, strict equivalency requirements may complicate trading of offset credits, increase costs due to restricted offset placement options, and force offset activities to focus on features that may not represent regional conservation priorities. Using the oil sands industry of Alberta, Canada, as a case study, we evaluated the economic and ecological performance of alternative offset systems targeting either ecologically equivalent areas (vegetation types) or regional conservation priorities (caribou and the Dry Mixedwood natural subregion). Exchanging dissimilar biodiversity elements requires assessment via a generalized metric; we used an empirically derived index of biodiversity intactness to link offsets with losses incurred by development. We considered 2 offset activities: land protection, with costs estimated as the net present value of profits of petroleum and timber resources to be paid as compensation to resource tenure holders, and restoration of anthropogenic footprint, with costs estimated from existing restoration projects. We used the spatial optimization tool MARXAN to develop hypothetical offset networks that met either the equivalent-vegetation or conservation-priority targets. Networks that required offsetting equivalent vegetation cost 2-17 times more than priority-focused networks. This finding calls into question the prudence of equivalency-based systems, particularly in relatively undeveloped jurisdictions, where conservation focuses on limiting and directing future losses. Priority-focused offsets may offer benefits to industry and environmental stakeholders by allowing for lower-cost conservation of valued ecological features and may invite discussion on what land-use trade-offs are acceptable when trading biodiversity via offsets. Resultados Económicos y Ecológicos de Sistemas de Compensación de

  1. Ecological epigenetics.

    Kilvitis, Holly J; Alvarez, Mariano; Foust, Christy M; Schrey, Aaron W; Robertson, Marta; Richards, Christina L

    2014-01-01

    Biologists have assumed that heritable variation due to DNA sequence differences (i.e., genetic variation) allows populations of organisms to be both robust and adaptable to extreme environmental conditions. Natural selection acts on the variation among different genotypes and ultimately changes the genetic composition of the population. While there is compelling evidence about the importance of genetic polymorphisms, evidence is accumulating that epigenetic mechanisms (e.g., chromatin modifications, DNA methylation) can affect ecologically important traits, even in the absence of genetic variation. In this chapter, we review this evidence and discuss the consequences of epigenetic variation in natural populations. We begin by defining the term epigenetics, providing a brief overview of various epigenetic mechanisms, and noting the potential importance of epigenetics in the study of ecology. We continue with a review of the ecological epigenetics literature to demonstrate what is currently known about the amount and distribution of epigenetic variation in natural populations. Then, we consider the various ecological contexts in which epigenetics has proven particularly insightful and discuss the potential evolutionary consequences of epigenetic variation. Finally, we conclude with suggestions for future directions of ecological epigenetics research.

  2. Research in remote sensing of vegetation

    Schrumpf, Barry J.; Ripple, William J.; Isaacson, Dennis L.

    1988-01-01

    The research topics undertaken were primarily selected to further the understanding of fundamental relationships between electromagnetic energy measured from Earth orbiting satellites and terrestrial features, principally vegetation. Vegetation is an essential component in the soil formation process and the major factor in protecting and holding soil in place. Vegetation plays key roles in hydrological and nutrient cycles. Awareness of improvement or deterioration in the capacity of vegetation and the trends that those changes may indicate are, therefore, critical detections to make. A study of the relationships requires consideration of the various portions of the electromagnetic spectrum; characteristics of detector system; synergism that may be achieved by merging data from two or more detector systems or multiple dates of data; and vegetational characteristics. The vegetation of Oregon is sufficiently diverse as to provide ample opportunity to investigate the relationships suggested above several vegetation types.

  3. Information Ecology

    Christiansen, Ellen Tove

    2006-01-01

    The paper describes a pedagogical didactical paradigm for teaching student-designers how to deal with context issues. Form/context-relationships are conceptualized as information ecologies and described as behavioral settings using a key concept developed by social psychologist R.A. Baker...... in the 1960ties, and chosen here because it integrates cultural and psychological trajectories in a theory of living settings. The pedagogical-didactical paradigm comprises three distinct information ecologies, named after their intended outcome: the problem-setting, the exploration-setting, and the fit......-setting. It is specified how context issues can be treated within each of these information ecologies. The paper concludes by discussing the outcome of applying this paradigm with respect to the student-designers’ competence as reflective practitioners....

  4. An ecohydrological approach to predicting hillslope-scale vegetation patterns and dynamics in dryland ecosystems

    Franz, Trenton; King, Elizabeth

    2015-04-01

    Drylands are an important ecosystem, as they cover over 40% of the Earth's land surface and are know to exhibit threshold behavior in response to climatic change and anthropogenic disturbance. Where dryland vegetation supports pastoralist livestock production, catastrophic ecological shifts present a grave concern because of the direct coupling between the livestock forage available and human livelihoods. In this research we investigate the spatiotemporal organization of grazing resources on hillslopes by developing a relatively simple spatially explicit daily stochastic ecohydrological 1-layer bucket model with dynamic vegetation and grazing components. The model, MVUA MINGI (Mosaic Vegetation Using Agent-based Modeling Incorporating Non-linear Grazing Impacts), was constructed using a 2-year observational study in central Kenya combining in-situ sensors with near surface hydrogeophysical surveys. The data were used to derive an empirical patch water balance of three representative patch types, bare soil, grass, and tree. Visual and hydrogeophysical observations indicated the system is dominated by Hortonian runoff, overland flow, and vertical infiltration of water into vegetation patches. The patch-based water balances were next incorporated into a Cellular Automata model allowing us to simulate a range of surface flowpath convergence states across the hillslope during a rain event. The model also allows the root to canopy radius of the tree patches to vary affecting the length scale of water competition. By changing the length scales of facilitation and competition, we find the model demonstrates a range of most efficient static vegetation patterns from random to highly organized. In order simulate the vegetation dynamics we incorporated continuous transition probabilities for each patch type based on the frequency and duration of drought and grazing intensity. The modeled vegetation dynamics indicate various stable states and the timescales between the state

  5. Vegetation communities associated with the 100-Area and 200-Area facilities on the Hanford Site

    Stegen, J.A.

    1994-01-17

    The Hanford Site, Benton County, Washington, lies within the broad semi-arid shrub-steppe vegetation zone of the Columbia Basin. Thirteen different habitat types on the Hanford Site have been mapped in Habitat Types on the Hanford Site: Wildlife and Plant Species of Concern (Downs et al. 1993). In a broad sense, this classification is correct. On a smaller scale, however, finer delineations are possible. This study was conducted to determine the plant communities and estimate vegetation cover in and directly adjacent to the 100 and 200 Areas, primarily in relation to waste sites, as part of a comprehensive ecological study for the Compensation Environmental Response, Compensation, and Liability Act (CERCLA) characterization of the 100 and 200 Areas. During the summer of 1993, field surveys were conducted and a map of vegetation communities in each area, including dominant species associations, was produced. The field surveys consisted of qualitative community delineations. The community delineations described were made by field reconnaissance and are qualitative in nature. The delineations were made by visually determining the dominant plant species or vegetation types and were based on the species most apparent at the time of inspection. Additionally, 38 transects were run in these plant communities to try to obtain a more accurate representation of the community. Because habitat disturbances from construction/operations activities continue to occur in these areas, users of this information should be cautious in applying these maps without a current ground survey. This work will complement large-scale habitat maps of the Hanford Site.

  6. Using historic aerial photography and paleohydrologic techniques to assess long-term ecological response to two Montana dam removals.

    Schmitz, Denine; Blank, Matt; Ammondt, Selita; Patten, Duncan T

    2009-07-01

    The restorative potential of dam removal on ecosystem function depends on the reversibility of dam effects and its operations. While dam removal is an established engineering practice, the need for an understanding of the ecological response remains. We used paleoflood hydrology, hydrologic modeling, and aerial photo interpretation to investigate the long-term ecologic responses to dam failure and breach. We investigated downstream geomorphic and vegetation responses to a dam failure (Pattengail Dam in 1927) and a controlled dam breach, which used natural sediment removal (Mystic Lake Dam in 1985). Our data showed vegetation responses indicative of channel and floodplain evolution at Pattengail. The size of the flood following the Pattengail dam failure initiated a series of channel adjustments and reworked over 19ha of floodplain downstream of the dam. In Mystic, we observed few flood stage indicators and a slight response in floodplain vegetation. We made several findings. (1) Dam removal effects on channel evolution and floodplain development depend on reach types and their responsiveness to flow regime change. (2) Ecologic response to dam removal depends on the sizes and timing of high flow events during and following removal. (3) Paleohydrology can be used to assess historic floods (>20 years). We see the utility of assessing the ecological responsiveness of a system to previous fluvial events or changes in flow regime. Informed about the character of a system based on its history, dam removal scientists can use these tools to set realistic restoration goals for removing a dam.

  7. Verification of watershed vegetation restoration policies, arid China

    Zhang, Chengqi; Li, Yu

    2016-07-01

    Verification of restoration policies that have been implemented is of significance to simultaneously reduce global environmental risks while also meeting economic development goals. This paper proposed a novel method according to the idea of multiple time scales to verify ecological restoration policies in the Shiyang River drainage basin, arid China. We integrated modern pollen transport characteristics of the entire basin and pollen records from 8 Holocene sedimentary sections, and quantitatively reconstructed the millennial-scale changes of watershed vegetation zones by defining a new pollen-precipitation index. Meanwhile, Empirical Orthogonal Function method was used to quantitatively analyze spatial and temporal variations of Normalized Difference Vegetation Index in summer (June to August) of 2000-2014. By contrasting the vegetation changes that mainly controlled by millennial-scale natural ecological evolution with that under conditions of modern ecological restoration measures, we found that vegetation changes of the entire Shiyang River drainage basin are synchronous in both two time scales, and the current ecological restoration policies met the requirements of long-term restoration objectives and showed promising early results on ecological environmental restoration. Our findings present an innovative method to verify river ecological restoration policies, and also provide the scientific basis to propose future emphasizes of ecological restoration strategies.

  8. Fractals in Spatial Patterns of Vegetation Formations

    SONG Zhiyuan; HUANG Daming; Masae Shiyomi; WANG Yusheng; Shigeo Takahashi; Hori Yoshimichi; Yasuo Yamamuru; CHEN Jun

    2006-01-01

    The spatial distribution patterns of species are always scale-dependent and spatially self-similar in ecological systems. In this work, vegetation distribution data collected from the vegetation map of the Xigazê region was analyzed using a box-counting method. The power law of the box-counting dimension (DB) across a range of scales (5-160 km) confirms the fractal patterns for most vegetation formations, while the fluctuations of the scale-specific DB among the different abundance groups indicate limitations of fractal coherence. The fractal method is shown to be a useful tool for measuring the distribution patterns of vegetation formations across scales, which provides important information for both species and habitat conservation, especially in landscape management.

  9. Vegetables, fruit, and cancer prevention: a review.

    Steinmetz, K A; Potter, J D

    1996-10-01

    In this review of the scientific literature on the relationship between vegetable and fruit consumption and risk of cancer, results from 206 human epidemiologic studies and 22 animal studies are summarized. The evidence for a protective effect of greater vegetable and fruit consumption is consistent for cancers of the stomach, esophagus, lung, oral cavity and pharynx, endometrium, pancreas, and colon. The types of vegetables or fruit that most often appear to be protective against cancer are raw vegetables, followed by allium vegetables, carrots, green vegetables, cruciferous vegetables, and tomatoes. Substances present in vegetables and fruit that may help protect against cancer, and their mechanisms, are also briefly reviewed; these include dithiolthiones, isothiocyanates, indole-3-carbinol, allium compounds, isoflavones, protease inhibitors, saponins, phytosterols, inositol hexaphosphate, vitamin C, D-limonene, lutein, folic acid, beta carotene, lycopene, selenium, vitamin E, flavonoids, and dietary fiber. Current US vegetable and fruit intake, which averages about 3.4 servings per day, is discussed, as are possible noncancer-related effects of increased vegetable and fruit consumption, including benefits against cardiovascular disease, diabetes, stroke, obesity, diverticulosis, and cataracts. Suggestions for dietitians to use in counseling persons toward increasing vegetable and fruit intake are presented.

  10. Is grazing exclusion effective in restoring vegetation in degraded alpine grasslands in Tibet, China?

    Yan, Yan; Lu, Xuyang

    2015-01-01

    Overgrazing is considered one of the key disturbance factors that results in alpine grassland degradation in Tibet. Grazing exclusion by fencing has been widely used as an approach to restore degraded grasslands in Tibet since 2004. Is the grazing exclusion management strategy effective for the vegetation restoration of degraded alpine grasslands? Three alpine grassland types were selected in Tibet to investigate the effect of grazing exclusion on plant community structure and biomass. Our results showed that species biodiversity indicators, including the Pielou evenness index, the Shannon-Wiener diversity index, and the Simpson dominance index, did not significantly change under grazing exclusion conditions. In contrast, the total vegetation cover, the mean vegetation height of the community, and the aboveground biomass were significantly higher in the grazing exclusion grasslands than in the free grazed grasslands. These results indicated that grazing exclusion is an effective measure for maintaining community stability and improving aboveground vegetation growth in alpine grasslands. However, the statistical analysis showed that the growing season precipitation (GSP) plays a more important role than grazing exclusion in which influence on vegetation in alpine grasslands. In addition, because the results of the present study come from short term (6-8 years) grazing exclusion, it is still uncertain whether these improvements will be continuable if grazing exclusion is continuously implemented. Therefore, the assessments of the ecological effects of the grazing exclusion management strategy on degraded alpine grasslands in Tibet still need long term continued research.

  11. Is grazing exclusion effective in restoring vegetation in degraded alpine grasslands in Tibet, China?

    Yan Yan

    2015-06-01

    Full Text Available Overgrazing is considered one of the key disturbance factors that results in alpine grassland degradation in Tibet. Grazing exclusion by fencing has been widely used as an approach to restore degraded grasslands in Tibet since 2004. Is the grazing exclusion management strategy effective for the vegetation restoration of degraded alpine grasslands? Three alpine grassland types were selected in Tibet to investigate the effect of grazing exclusion on plant community structure and biomass. Our results showed that species biodiversity indicators, including the Pielou evenness index, the Shannon–Wiener diversity index, and the Simpson dominance index, did not significantly change under grazing exclusion conditions. In contrast, the total vegetation cover, the mean vegetation height of the community, and the aboveground biomass were significantly higher in the grazing exclusion grasslands than in the free grazed grasslands. These results indicated that grazing exclusion is an effective measure for maintaining community stability and improving aboveground vegetation growth in alpine grasslands. However, the statistical analysis showed that the growing season precipitation (GSP plays a more important role than grazing exclusion in which influence on vegetation in alpine grasslands. In addition, because the results of the present study come from short term (6–8 years grazing exclusion, it is still uncertain whether these improvements will be continuable if grazing exclusion is continuously implemented. Therefore, the assessments of the ecological effects of the grazing exclusion management strategy on degraded alpine grasslands in Tibet still need long term continued research.

  12. 武汉现代新型城市圈文化生态培育的路径选择%Access Selecting of Cultural Ecological Cultivation in the Modern New-type Urban Circle of Wuhan

    方爱清

    2011-01-01

    The changing time leads to the change of our cultural ecology.The fact that the modern new-type urban circle of Wuhan was approved by the state government as a reforming experimental zone comprehensively assorted with construction of the "two-type society" is a good chance for historical development in constructing cultural ecology.The paper is to analyze the logical relationships between construction of the "two-type society" and cultural ecology,to observe the new demand of the construction of "two-type society" for the cultural ecology in the modern new-type urban circle of Wuhan,and to raise basic way of thinking about the construction of the cultural ecology of the modern new-type urban circle of Wuhan from a point of the chance and difficulties concerning the present construction of "two-type" society" faced by Wuhan City".Special attention is given to Wuhan's reality.%时代的变迁使我们的文化生态发生了变化。武汉现代新型城市圈被国家正式批准为"两型社会"建设综合配套改革试验区,对于文化生态建设来说,是一个难得的历史性发展机遇。剖析"两型社会"建设与文化生态之间的逻辑关系,透视"两型社会"建设对武汉现代新型城市圈文化生态的新要求,从武汉市当前"两型社会"建设所面临的机遇和困境着手,重点结合武汉实际,提出武汉现代新型城市圈生态文化建设的基本思路。

  13. Bacterial Ecology

    Fenchel, Tom

    2011-01-01

    Bacterial ecology is concerned with the interactions between bacteria and their biological and nonbiological environments and with the role of bacteria in biogeochemical element cycling. Many fundamental properties of bacteria are consequences of their small size. Thus, they can efficiently exploit...

  14. The South African National Vegetation Database: History, development, applications, problems and future

    Leslie W. Powrie

    2012-01-01

    Full Text Available Southern Africa has been recognised as one of the most interesting and important areas of the world from an ecological and evolutionary point of view. The establishment and development of the National Vegetation Database (NVD of South Africa enabled South Africa to contribute to environmental planning and conservation management in this floristically unique region. In this paper, we aim to provide an update on the development of the NVD since it was last described, near its inception, more than a decade ago. The NVD was developed using the Turboveg software environment, and currently comprises 46 697 vegetation plots (relevés sharing 11 690 plant taxa and containing 968 943 species occurrence records. The NVD was primarily founded to serve vegetation classification and mapping goals but soon became recognised as an important tool in conservation assessment and target setting. The NVD has directly helped produce the National Vegetation Map, National Forest Type Classification, South African National Biodiversity Assessment and Forest Type Conservation Assessment. With further development of the NVD and more consistent handling of the legacy data (old data sets, the current limitations regarding certain types of application of the data should be significantly reduced. However, the use of the current NVD in multidisciplinary research has certainly not been fully explored. With the availability of new pools of well-trained vegetation surveyors, the NVD will continue to be purpose driven and serve the needs of biological survey in pursuit of sustainable use of the vegetation and flora resources of the southern African subcontinent.

  15. Roosting ecology and the evolution of pelage markings in bats.

    Santana, Sharlene E; Dial, Thomas O; Eiting, Thomas P; Alfaro, Michael E

    2011-01-01

    Multiple lineages of bats have evolved striking facial and body pelage makings, including spots, stripes and countershading. Although researchers have hypothesized that these markings mainly evolved for crypsis, this idea has never been tested in a quantitative and comparative context. We present the first comparative study integrating data on roosting ecology (roost type and colony size) and pelage coloration patterns across bats, and explore the hypothesis that the evolution of bat pelage markings is associated with roosting ecologies that benefit from crypsis. We find that lineages that roost in the vegetation have evolved pelage markings, especially stripes and neck collars, which may function in crypsis through disruptive coloration and a type of countershading that might be unique to bats. We also demonstrate that lineages that live in larger colonies and are larger in size tend not to have pelage markings, possibly because of reduced predation pressures due to the predator dilution effect and a lower number of potential predators. Although social functions for pelage color patterns are also possible, our work provides strong support for the idea that roosting ecology has driven the evolution of pelage markings in bats.

  16. ECOLOGICAL FEATURES OF ALGAE COMMUNITIES IN FOREST FLOOR OF PINE PLANTATIONS OF DIFFERENT TYPES OF LANDSCAPES IN STEPPE AREA OF UKRAINE

    Maltsev Yevhen

    2013-12-01

    Full Text Available The steppe zone of Ukraine features a large variety of types of natural landscapes that together significantly differ in microclimatic, soil, hydrological and geobotanic conditions. Such a diversity of forest conditions affects not only the trees, but also on all biotic components of forest ecosystems including algae. Purpose of the study was establish systematic position of species, dominant and subdominant, leading families of algae for plantings in forest floor of pine plantations of the valley-terrace and inundable-terrace landscapes in steppe area of Ukraine. In general, in the forest floor of Samara pine forest marked 34 species of algae with 4 divisions, most of which related to green: Chlorophyta – 22 (65%, Xanthophyta – 8 (23%, Bacillariophyta – 2 (6% and Eustigmatophyta – 2 (6%. Among the leading families of the greatest number of species belonged to: Pleurochloridaceae (7 species, Chlorococcaceae (5, Chlamydomonadaceae (4. During all studied seasons in base of algae communities were species resistant to extreme values of all climatic conditions. Total in forest floor of pine forest in Altagir forest marked 42 species of algae with 5 divisions: Chlorophyta - 23 (55 %, Xanthophyta - 9 (21 %, Cyanophyta - 5 (12 %, Bacillariophyta - 3 (7% and Eustigmatophyta – 2 (5%. Systematic structure of list species determine three family, which have the number of species in excess of the average number (2: Pleurochloridaceae, Chlamydomonadaceae and Myrmeciaceae. The base of algae community are moisture-loving and shade-tolerant species, which may be the result of favorable moisture regime. In the forest floor of pine plantings in forest floor of pine plantations of the valley-terrace (Samara pine forest and inundable-terrace (Altagir forest landscapes found 64 species of algae with 5 divisions, which are dominated by green algae - 37 species (58%, that exceed xanthophytes - 15 (23%, blue-green 5 (8 %, eustigmatofites 4 (6% and diatoms 3 (5

  17. Vegetation of natural and artificial shorelines in Upper Klamath Basin’s fringe wetlands

    Ray, Andrew M.; Irvine, Kathryn M.; Hamilton, Andy S.

    2013-01-01

    The Upper Klamath Basin (UKB) in northern California and southern Oregon supports large hypereutrophic lakes surrounded by natural and artificial shorelines. Lake shorelines contain fringe wetlands that provide key ecological services to the people of this region. These wetlands also provide a context for drawing inferences about how differing wetland types and wave exposure contribute to the vegetative assemblages in lake-fringe wetlands. Here, we summarize how elevation profiles and vegetation richness vary as a function of wave exposure and wetland type. Our results show that levee wetland shorelines are 4X steeper and support fewer species than other wetland types. We also summarize the occurrence probability of the five common wetland plant species that represent the overwhelming majority of the diversity of these wetlands. In brief, the occurrence probability of the culturally significant Nuphar lutea spp. polysepala and the invasive Phalaris arundinacea in wave exposed and sheltered sites varies based on wetland type. The occurrence probability for P. arundinacea was greatest in exposed portions of deltaic shorelines, but these trends were reversed on levees where the occurrence probability was greater in sheltered sites. The widespread Schoenoplectus acutus var. acutus occurred throughout all wetland and exposure type combinations but had a higher probability of occurrence in wave exposed sites. Results from this work will add to our current understanding of how wetland shoreline profiles interact with wave exposure to influence the occurrence probability of the dominant vegetative species in UKB’s shoreline wetlands.

  18. [American cutaneous leishmaniasis in municipalities in the northwestern region of Paraná State: use of remote sensing for analysis of vegetation types and places with disease occurrence].

    Arraes, Sandra Mara Alessi Aristides; Veit, Renata Tonon; Bernal, Marcos Vinícius Zandonadi; Becker, Tânia Cristina Alexandrino; Nanni, Marcos Rafael

    2008-01-01

    American cutaneous leishmaniasis, an endemic disease in the northwestern region of Paraná, Brazil, is transmitted by phlebotomines to man and animals like dogs, armadillos, opossums and wild rodents. This disease has been occurring in places where forests have been felled and on the banks of rivers and lakes with arboreal vegetation, where man comes into contact with infected insects. This disease is a public health problem because of the occurrence of epidemic outbreaks throughout Paraná. Because of the importance of finding out about endemic areas, this study used epidemiological file data on patients attended between 1999 and 2004. These data were correlated with areas of forest felling that were identified by means of satellite remote sensing techniques and products. The results showed that the occurrences of cases in the municipalities of this region coincided with the presumed likely areas for patient infection.

  19. Effects of fertilization on the vascular ground vegetation of European beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Lieb.) stands

    Misson, Laurent; Gaëtan Du Bus De Warnaffe,; Jonard, Mathieu

    2001-01-01

    International audience; The objective of this study was to assess the effects of base cation (Ca, Mg, K) and phosphorous (P) fertilization on the vascular ground vegetation in mature European beech and sessile oak stands located on acid brown soils. Two types of treatment were applied next to control plots (dolomite lime, dolomite lime + natural phosphate + potassium sulphate). Specific richness, total cover (% ), equitability coefficient as well as the Ecological Group of the ground vegetati...

  20. Effects of pomegranate and pomegranate-apple blend juices on the growth characteristics of Alicyclobacillus acidoterrestris DSM 3922 type strain vegetative cells and spores.

    Molva, Celenk; Baysal, Ayse Handan

    2015-05-04

    The present study examined the growth characteristics of Alicyclobacillus acidoterrestris DSM 3922 vegetative cells and spores after inoculation into apple, pomegranate and pomegranate-apple blend juices (10, 20, 40 and 80%, v/v). Also, the effect of sporulation medium was tested using mineral [Bacillus acidoterrestris agar (BATA) and Bacillus acidocaldarius agar (BAA)] and non-mineral containing media [potato dextrose agar (PDA) and malt extract agar (MEA)]. The juice samples were inoculated separately with approximately 10(5)CFU/mL cells or spores from different sporulation media and then incubated at 37°C for 336 h. The number of cells decreased significantly with increasing pomegranate juice concentration in the blend juices and storage time (ppomegranate juices, respectively while the cell counts attained approximately 7.17 log CFU/mL in apple juice after 336 h. On the other hand, the cell growth was inhibited for a certain time, and then the numbers started to increase after 72 and 144 h in 10% and 20% blend juices, respectively. After 336 h, total population among spores produced on PDA, BATA, BAA and MEA indicated 1.49, 1.65, 1.67, and 1.28 log reductions in pomegranate juice; and 1.51, 1.38, 1.40 and 1.16 log reductions in 80% blend juice, respectively. The inhibitory effects of 10%, 20% and 40% blend juices varied depending on the sporulation media used. The results obtained in this study suggested that pomegranate and pomegranate-apple blend juices could inhibit the growth of A. acidoterrestris DSM 3922 vegetative cells and spores.

  1. A review and synthesis of recreation ecology research findings on visitor impacts to wilderness and protected natural areas

    Marion, Jeff; Leung, Yu-Fai; Eagleston, Holly; Burroughs, Kaitlin

    2016-01-01

    The 50th anniversary of the US Wilderness Act of 1964 presents a worthy opportunity to review our collective knowledge on how recreation visitation affects wilderness and protected natural area resources. Studies of recreation impacts, examined within the recreation ecology field of study, have spanned 80 years and generated more than 1,200 citations. This article examines the recreation ecology literature most relevant to wilderness and backcountry, with a focus on visitor impacts to vegetation, soil, wildlife, and water resources. We also review relationships with influential factors, such as the amount of use, visitor behavior, and vegetation type. An understanding of these impacts and their relationships with influential factors is necessary for land managers seeking to identify acceptable limits of impact or selecting management actions that will effectively avoid or minimize resource impacts.

  2. Dynamic Response of Satellite-Derived Vegetation Growth to Climate Change in the Three North Shelter Forest Region in China

    Bin He

    2015-08-01

    Full Text Available Since the late 1970s, the Chinese government has initiated ecological restoration programs in the Three North Shelter Forest System Project (TNSFSP area. Whether accelerated climate change will help or hinder these efforts is still poorly understood. Using the updated and extended AVHRR NDVI3g dataset from 1982 to 2011 and corresponding climatic data, we investigated vegetation variations in response to climate change. The results showed that the overall state of vegetation in the study region has improved over the past three decades. Vegetation cover significantly decreased in 23.1% and significantly increased in 21.8% of the study area. An increase in all three main vegetation types (forest, grassland, and cropland was observed, but the trend was only statistically significant in cropland. In addition, bare and sparsely vegetated areas, mainly located in the western part of the study area, have significantly expanded since the early 2000s. A moisture condition analysis indicated that the study area experienced significant climate variations, with warm-wet conditions in the western region and warm-dry conditions in the eastern region. Correlation analysis showed that variations in the Normalized Difference Vegetation Index (NDVI were positively correlated with precipitation and negatively correlated with temperature. Ultimately, climate change influenced vegetation growth by controlling the availability of soil moisture. Further investigation suggested that the positive impacts of precipitation on NDVI have weakened in the study region, whereas the negative impacts from temperature have been enhanced in the eastern study area. However, over recent years, the negative temperature impacts have been converted to positive impacts in the western region. Considering the variations in the relationship between NDVI and climatic variables, the warm–dry climate in the eastern region is likely harmful to vegetation growth, whereas the warm

  3. Weed Identification and Control in Vegetable Crops.

    Ferretti, Peter A., Comp.

    This agriculture extension service publication from Pennsylvania State University examines weed control and identification in vegetable crops. Contents include: (1) Types of weeds; (2) Reducing losses caused by weeds, general control methods and home garden weed control; (3) How herbicides are used; (4) Specific weeds in vegetable plantings; and…

  4. HEAVY METALS ACCUMULATION IN GREENHOUSE VEGETABLE PRODUCTION SYSTEMS AND ITS ECOLOGICAL EFFECTS%设施蔬菜生产系统重金属积累特征及生态效应

    陈永; 黄标; 胡文友; 杨岚钦; 毛明翠

    2013-01-01

    To study spatial variability of soil heavy metals may help reveal effects of human activities on soil heavy metals accumulation and provide important basic data for soil utilization and its pollution risk assessment.Based on systematical analysis of heavy metals,arsenic (As),cadmium (Cd),copper (Cu),mercury (Hg),lead (Pb),zinc (Zn)in the environmental media,such as soil,irrigation water,fertilizer,and plants of a greenhouse vegetable production system typical of the suburbs of Nanjing,spatial variability and accumulation of heavy metals in the soil was explored causes of the accumulation analyzed,and effect of the accumulation on plant uptake of heavy metals in this system discussed.Results show that (1) accumulation of Cu,Hg,Pb,and Zn in the soil was significant compared with that in open fields,and the average contents of Cu,Hg,and Pb in the soil were higher than the criteria set in the Environmental Quality Evaluation Standard for Farmland in Greenhouse Vegetable Production ; (2) Large amounts of agro-inputs significantly affected spatial variability of soil properties,and hence,the spatial variability of soil Cu,Hg,Pb,and Zn in a similar way,for these elements were closely correlated with soil properties; and (3) The changes in soil properties and the accumulation of heavy metals strongly affected leaf vegetable' s uptake of heavy metals,and the former played a more important role.%研究土壤重金属的空间变异特征,可以揭示人为活动对土壤中重金属积累特征的影响,进而为土壤利用、污染风险评价提供重要的基础资料.选取南京市郊区一处典型的设施蔬菜生产系统为研究对象,测定了土壤、灌溉用水、肥料、蔬菜等介质中重金属砷(As)、镉(Cd)、铜(Cu)、汞(Hg)、铅(Pb)、锌(Zn)含量,研究了土壤中重金属的空间变异及积累特征,分析了积累产生的原因,讨论了系统中作物的重金属积累效应.结果表明:(1)与露天蔬菜地相比,设施蔬菜地土壤

  5. Effects of landscape gradients on wetland vegetation communities: information for large-scale restoration

    Zweig, Christa L.; Kitchens, Wiley M.

    2008-01-01

    Projects of the scope of the restoration of the Florida Everglades require substantial information regarding ecological mechanisms, and these are often poorly understood. We provide critical base knowledge for Everglades restoration by characterizing the existing vegetation communities of an Everglades remnant, describing how present and historic hydrology affect wetland vegetation community composition, and documenting change from communities described in previous studies. Vegetation biomass samples were collected along transects across Water Conservation Area 3A South (3AS). Ten community types were present between November 2002 and 2005. Separate analyses for key a priori groups (slough, wet prairie, and sawgrass) provided detailed conclusions about effects of historic hydrology on the vegetation of 3AS. Communities were affected by hydrologic variables LIP to four years previous to the sample. We identified wet prairie/slough species such as Eleocharis spp. and Nymphaea odorata as short-term sentinel species of community change. Sawgrass and N. odorata should be monitored for long-term change. Comparisons to preceding studies indicated that many of the communities of previous times, when conditions were drier, no longer exist in our study area and have been replaced by deeper water community types.

  6. Comparative analysis of two vegetation types and its ecotone, Miranda - MS Análise comparativa de duas formações vegetacionais e de seu ecótono, Miranda - MS

    Mariana Chaves Mota

    2011-12-01

    Full Text Available The Pantanal consists of different vegetation types, including the Paratudal, a monodominat floodable savanna, and Riparian vegetation. This study aimed to analyze diversity and similarity in samples ofthese two vegetations, and its ecotone. The study was developed in the region of Passo do Lontra, at the Miranda river margins. Five plots 10 x 10m, were allocated in each area, where all individuals above 1m height were counted and identified. Nine hundred and thirteen individuals were registered, distributed in 70 taxa, of which 60 were identified in species level. The Shannon diversity index (H’ was 2.715 with Pielou Eveness (J’ of 0.806 in Paratudal, 3.010 and 0.835 in Riparian vegetation, and 2.739 and 0.797 in ecotone, respectively. These results show highest diversity in the Riparian vegetation, as expected, since the Paratudal’s ambient conditions are more restrictive. The floristic similarity between the Paratudal and the Riparian vegetation, according to the Sorensen index, was of 0.2, what distinguish both environments. Therefore, this study evidences the distinction among Riparian vegetation andParatudal, as well the existence of an intermediary values with ecotone. O Pantanal é constituído por diferentes formações vegetacionais, entre elas o Paratudal e a Mata Ciliar. Este trabalho objetivou analisar comparativamente essas duas formações, e o ecótono entre elas, quanto à diversidade e similaridade. O estudo foi desenvolvido na região do Passo do Lontra, às margens do rio Miranda, MS. Foram estabelecidas cinco parcelas de 10 x 10m em cada área e nelas todos os indivíduos acima de 1m de altura foram contados e identificados. Foram registrados 913 indivíduos, distribuídos em 70 taxa, dos quais 60 foram identificados em nível de espécie. O índice de diversidade de Shannon (H’ foi 2,715 com equidade de Pielou (J’ de 0,806 no Paratudal; 3,010 e 0,835 na MataCiliar; e 2,739 e 0,797 no ecótono, respectivamente

  7. Sensitivity of vegetation indices to different burn and vegetation ratios using LANDSAT-5 satellite data

    Pleniou, M.; Koutsias, N.

    2013-08-01

    The application of vegetation indices is a very common approach in remote sensing of burned areas to either map the fire scar or estimate burn severity since they minimize the effect of exogenous factors and enhance the correlation with the internal parameters of vegetation. In a recent study we found that the original spectral channels, based on which these indices are estimated, are sensitive to external parameters of the vegetation as for example the spectral reflectance of the background soil. In such cases, the influence of the soil in the reflectance values is different in the various spectral regions depending on its type. These problems are further enhanced by the non-homogeneous pixels, as created from fractions of different types of land cover. Parnitha (Greece), where a wildfire occurred on July 2007, was established as test site. The purpose of this work is to explore the sensitivity of vegetation indices when used to estimate and map different fractions of fire-scorched (burned) and non fire-scorched (vegetated) areas. IKONOS, a very high resolution satellite imagery, was used to create a three-class thematic map to extract the percentages of vegetation, burned surfaces, and bare soil. Using an overlaid fishnet we extracted samples of completely "burned", completely "vegetated" pixels and proportions with different burn/vegetation ratios (45%-55% burned - 45%-55% vegetation, 20%-30% burned - 70%- 80% vegetation, 70%-80% burned - 20%-30% vegetation). Vegetation indices were calculated (NDVI, IPVI, SAVI) and their values were extracted to characterize the mentioned classes. The main findings of our recent research were that vegetation indices are less sensitive to external parameters of the vegetation by minimizing external effects. Thus, the semi-burned classes were spectrally more consistent to their different fractions of scorched and non-scorched vegetation, than the original spectral channels based on which these indices are estimated.

  8. Analysis of Adenoid Vegetation Children with Different Types of Tympanograms and Secretory Otitis Media%腺样体肥大患儿鼓室导抗图与分泌性中耳炎的关系探讨

    高永平; 田从哲; 刘会清; 孟胜环; 刘海燕

    2013-01-01

    目的:探讨腺样体肥大患儿的不同鼓室导抗图与分泌性中耳炎的关系。方法回顾性分析2009年1月~2011年6月收治的328例腺样体肥大患儿的临床资料,分析统计分泌性中耳炎的发病例(耳)数及声导抗测试诊断分泌性中耳炎的阳性率。结果328例腺样体肥大患儿中有104例(169耳)最终经鼓膜穿刺或鼓膜置管确诊为分泌性中耳炎(31.71%,104/328),其中鼓室导抗图为B型者89例152耳,最终确诊为分泌性中耳炎者为86例147耳,阳性率为96.71%(147/152);鼓室导抗图为C型(负压在-150 daPa以上)者33例49耳,最终确诊为分泌性中耳炎者为16例20耳,阳性率为40.82%(20/49);鼓室导抗图为A s型者2例2耳最终均确诊为分泌性中耳炎。结论腺样体肥大患儿无论有无听力下降主诉,均应行声导抗测试,B型鼓室导抗图对鼓室积液判断的准确率最高,C型次之,As型也有鼓室积液的可能。%Objective To explore the relationship between adenoid vegetation children with different types of tympanograms and secretory otitis media in children and diagnosis of secretory otitis media .Methods A retrospec-tive study was carried out among 328 cases with adenoid vegetation in children ,including simple adenoid vegetation and associated with chronic tonsillitis and tonsillar hypertrophy ,from August 2010 to May 2012 .The incidence of secretory otitis media and outcomes of tympanometry for the diagnosis were analyzed .Results 104 cases were diag-nosed with secretory otitis media by tympanic membrane puncture or tympanostomy tube in 328 cases with adenoid vegetation (32 .31% );86 cases (147 ears) were finally diagnosed as secretory otitis media among 89 cases (152 ears) with type B tympanogram (147/152 ,96 .63% );16 cases (20 ears) were finally diagnosed secretory otitis media among 33 cases (49 ears) with type C tympanogram (20/49 ,40 .82% );2 cases (2 ears) with

  9. Digitally determining forest inventory units with an ecological classification system

    TANG Lina; WANG Qingli; Guofan Shao; DAI Limin; WANG Shunzhong; LI Xiufen; XU Dong

    2006-01-01

    Management-level forest resource data in China were obtained with a combination of two forest inventories. However, inconsistencies in the spatial attributes of forest data vary between the two inventory types and between two inventories of the same type. The inconsistencies make it inconvenient for long-term forest management planning with digital technologies. Ecological Land Types (ELTs) and Ecological Land Type Phases (ELTPs) have been mapped in selected forestry regions in northeast China, where important forest industries are located. The boundaries of ELTs are determined by geomorphic conditions, which are quantified by Digital Elevation Models (DEM); ELTPs are classified by overlaying ELTs with forest vegetation data layers that are obtained with both remotely sensed and ground data. The ELTPs represent the divisions of land in terms of both natural and human-induced forest conditions, and therefore they are reliable units for forest inventories and management. This paper introduces a case study for digitally determining forest inventory units in Benxi City, Liaoning Province, northeast China. The general objective of the study was to explain how a compatible forest inventory system should be designed and why the compatible forest inventory system was significant to digital forestry in China.

  10. Challenges in writing ecological site descriptions

    The Natural Resources Conservation Service (NRCS) adopted the Ecological Site Description (ESD) concept in 1997. The State and Transition Model (STM) is used to describe vegetation dynamics and is an integral component of ESDs that meet users needs. NRCS is currently developing ESDs for much of the ...

  11. Global change and climate-vegetation classification

    2000-01-01

    Three phrases of the quantitative study of climate-vegetation classification and their characteristics are presented based on the review of advance in climate-vegetation interaction, a key issue of "global change and terrestrial ecosystems (GCTE)" which is the core project of International Geosphere-Biosphere Programme (IGBP): (ⅰ) characterized by the correlation between natural vegetation types and climate; (ⅱ) characterized by climatic indices which have obviously been restricted to plant ecophysiology; (ⅲ) characterized by coupling both structure and function of vegetation. Thus, the prospective of climate-vegetation classification for global change study in China was proposed, especially the study coupling climate-vegetation classification models with atmospheric general circulation models (GCMs) was emphasized.

  12. Terrestrial transect study on driving mechanism of vegetation changes

    2008-01-01

    In terms of Chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2) in China from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast China Transect (NECT) and the North-South Transect of Eastern China (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

  13. Influence of Watering with an enriched solution of surfactants on the soil properties and vegetation growth. Experimental model with two types of soils: district cambisol and calcaricum cambisol; Influencia del riego con solucion enriquecida en tensoactivos sobre las propiedades del suelo y el desarrollo vigetal

    Cruz Caravaca, M. T.; Crespo Alia, M. A. [Universidad Complutense. Madrid (Spain)

    2000-07-01

    A study done on the the influence of watering with an enriched solution of surfactants on the soil properties and vegetation growth using an experimental model with two types of soils, each one with different characteristic: district Cambisol and calcaricum Cambisol. The results show significant differences in conductivity, organic carbon content, clay content and in phosphates. As well, the sodium enrichment of the adjuvants components of the detergent employed significantly influence the content of free clay and the SAR values. The chosen vegetation was seen to be affected in these areas: sprouting, vegetal mass and principally in the amount of calcium foliage. (Author) 18 refs.

  14. 污染足迹:一种基于生态系统服务的生态足迹%Pollution Footprint: A Type of Ecological Footprint Based on Ecosystem Services

    闵庆文; 焦雯珺; 成升魁

    2011-01-01

    impacts lies in that the assumption of the exclusive land function has prevented the non-bioproductive commodities and services from being considered.To overcome the limitations in conventional ecological footprint theories, the authors suggested that the multi-functionality of land should be acknowledged.Furthermore, a concept of ecosystem services-based ecological footprint was proposed.The ecosystem services-based ecological footprint is defined as the aggregated area of land and water in a variety of ecological categories that is claimed by a certain group of population to provide all types of ecosystem services they consume.The authors also elaborated the model construction and calculation methods of ecosystem services-based ecological footprint, in particular pollution footprint.The pollution footprint, an ecological footprint based on pollution absorption, is a typical ecosystem services-based ecological footprint.It is noted that the pollution footprint is not a simple replacement of energy footprint in the conventional ecological footprint; it is able to account for most pollutants incurred by human activities and to be further clarified in terms of different classes or types of pollutants.Difficulties in pollution footprint calculation include 1) pollutant transfer mechanisms and 2) the determination of the quantity of pollutants for each type of land cover and the capability of these land covers to accommodate pollution.The difficulty in application rests on the determination of the relationship among footprints of different classes or types of pollutants.

  15. Chemical ecology of marine plankton.

    Schwartz, Emily R; Poulin, Remington X; Mojib, Nazia; Kubanek, Julia

    2016-07-28

    Covering: January 2013 to online publication December 2014This review summarizes recent research in the chemical ecology of marine pelagic ecosystems, and aims to provide a comprehensive overview of advances in the field in the time period covered. In order to highlight the role of chemical cues and toxins in plankton ecology this review has been organized by ecological interaction types starting with intraspecific interactions, then interspecific interactions (including facilitation and mutualism, host-parasite, allelopathy, and predator-prey), and finally community and ecosystem-wide interactions.

  16. The movement ecology of seagrasses.

    McMahon, Kathryn; van Dijk, Kor-Jent; Ruiz-Montoya, Leonardo; Kendrick, Gary A; Krauss, Siegfried L; Waycott, Michelle; Verduin, Jennifer; Lowe, Ryan; Statton, John; Brown, Eloise; Duarte, Carlos

    2014-11-22

    A movement ecology framework is applied to enhance our understanding of the causes, mechanisms and consequences of movement in seagrasses: marine, clonal, flowering plants. Four life-history stages of seagrasses can move: pollen, sexual propagules, vegetative fragments and the spread of individuals through clonal growth. Movement occurs on the water surface, in the water column, on or in the sediment, via animal vectors and through spreading clones. A capacity for long-distance dispersal and demographic connectivity over multiple timeframes is the novel feature of the movement ecology of seagrasses with significant evolutionary and ecological consequences. The space-time movement footprint of different life-history stages varies. For example, the distance moved by reproductive propagules and vegetative expansion via clonal growth is similar, but the timescales range exponentially, from hours to months or centuries to millennia, respectively. Consequently, environmental factors and key traits that interact to influence movement also operate on vastly different spatial and temporal scales. Six key future research areas have been identified.

  17. Ecological baseline studies in Los Alamos and Guaje Canyons County of Los Alamos, New Mexico. A two-year study

    Foxx, T.S. [comp.

    1995-11-01

    During the summers of 1993 and 1994, the Biological Resource Evaluations Team (BRET) of the Environmental Protection Group (ESH-8) conducted baseline studies within two canyon systems, Los Alamos and Guaje Canyons. Biological data was collected within each canyon to provide background and baseline information for Ecological Risk models. Baseline studies included establishment of permanent vegetation plots within each canyon along the elevational gradient. Then, in association with the various vegetation types, surveys were conducted for ground dwelling insects, birds, and small mammals. The stream channels associated with the permanent vegetation plots were characterized and aquatic macroinvertebrates collected within the stream monthly throughout a six-month period. The Geographic Position System (GPS) in combination with ARC INFO was used to map the study areas. Considerable data was collected during these surveys and are summarized in individual chapters.

  18. Graphic Ecologies

    Brook Weld Muller

    2014-12-01

    Full Text Available This essay describes strategic approaches to graphic representation associated with critical environmental engagement and that build from the idea of works of architecture as stitches in the ecological fabric of the city. It focuses on the building up of partial or fragmented graphics in order to describe inclusive, open-ended possibilities for making architecture that marry rich experience and responsive performance. An aphoristic approach to crafting drawings involves complex layering, conscious absence and the embracing of tension. A self-critical attitude toward the generation of imagery characterized by the notion of ‘loose precision’ may lead to more transformative and environmentally responsive architectures.

  19. The Weird Vegetable Price

    2011-01-01

    The Chinese Government faces the task of stabilizing vegetable prices to avoid steep increases and dips Fluctuations of vegetable prices in China have recently caused near panic in the domestic market.Purchase prices for farm produce are decreasing dramatically

  20. Total Vegetation 2002

    U.S. Geological Survey, Department of the Interior — These are polygons that contain vegetated pixels in the May, 2002 imagery from aerial overflight of the Grand Canyon. Vegetation was mapped between stage elevations...

  1. Procedures for Sampling Vegetation

    US Fish and Wildlife Service, Department of the Interior — This report outlines vegetation sampling procedures used on various refuges in Region 3. The importance of sampling the response of marsh vegetation to management...

  2. Characterization of Vegetation Change in a Sub-Arctic Mire using Remotely Sensed Imagery

    DelGreco, J. L.; McArthur, K. J.; Palace, M. W.; Herrick, C.; Garnello, A.; Finnell, D.; McCalley, C. K.; Anderson, S. M.; Varner, R. K.

    2015-12-01

    Climate change is impacting northern ecosystems through the thawing of the permafrost, which has resulted in changes to plant communities and greenhouse gas emissions, such as carbon dioxide (CO2) and methane (CH4). These greenhouse gases are of concern due to their potential feedbacks which create a warmer climate, thus increasing permafrost thawing. Our study focuses on how vegetation type differs in areas that have been impacted by thawing permafrost at Stordalen Mire located in Abisko, Sweden. To estimate change in vegetation communities, field-based measurements combined with remotely sensed image data was used. 75 randomized square-meter plots were measured for vegetation composition and classified into one of five site-types, each representing a different stage of permafrost degradation. New high-resolution imagery (1 cm) was collected using Unmanned Aerial Vehicles (UAV) providing insight into the spatial patterning, characterizations, and changes of these communities. The UAV imagery was georectified using high precision GPS points collected across the mire. The imagery was then examined using a neural network analysis to estimate cover type across the mire. This 2015 cover type classification was then compared to previous UAV imagery taken on July 2014 to analyze changes in vegetation distribution as an indication of permafrost thaw. Hummock sites represent intact permafrost and have lost 21.5% coverage since 2014, while tall gramminoid sites, which indicate fully thawed sites, have increased coverage by 12.1%. A discriminate function analysis showed that site types can be differentiated based on species composition, thus showing that vegetation differs significantly across the thaw gradient. Using average flux rates of CH4 from each cover type reported previously, the percent of CH4 emitted over the mire was estimated for 2014 and 2015. Comparing both estimates, CH4 emissions increased with a flux change of 5604.5 g CH4/day. Our estimates of vegetation

  3. 漓江鱼类生态类型及生物多样性变化情况%Ecological Types and Biodiversity of Fish in Lijiang River,Guilin,China

    朱瑜; 蔡德所; 周解; 韩耀全

    2012-01-01

    The ecological environment of the river is monitored through investigation of the ecological types and biodiversity of fish in Lijiang river. The results show that the biodiversity of fish in Lijiang river was higher,but with more genu of single species,sensitive species reduced greatly,the submucosa and benthic fish reduced significantly,the proportion of omnivorous fish increased,CPUE reduced,economic fish was of miniatunization and younger age. The ecological envirment of water is under great pressure.%本文通过对漓江水流域鱼类生态类型和鱼类生物多样性的变化进行调查,监测河流生态系统的情况.结果是,漓江鱼类物种多样性指数较高,但单种属较多;敏感性鱼类种类大幅度减少,中下层鱼类和底栖鱼类明显减少,杂食性鱼类比例上升;单位捕捞努力量渔获量减少,经济鱼类小型化,低龄化.水域生态环境存在较大的压力.

  4. Relationship between fire regime and vegetation symphenological timing in Sardinia

    Carlo Ricotta

    2008-01-01

    Full Text Available Fire is a basic ecological factor that contributes to determine vegetation biodiversity and dynamics in time and space. Fuel characteristics play an essential role in fire ignition and propagation; for instance fuel availability and flammability are closely related to the coarse-scale vegetation phenological trends that directly affect wildfire distribution in time and space. In this perspective, the annual NDVI profiles derived from high temporal resolution satellite images like SPOT Vegetation represent an effective tool for monitoring plant seasonal dynamics at the landscape scale. The objective of this study consists in relating the wildfire regime in Sardinia during 2000-2004 with the remotely sensed phenological parameters of the vegetation, segmented according to potential natural vegetation characteristics. The results of our study highlight a good correspondence between the NDVI temporal dynamics of the potential natural vegetation of Sardinia and the corresponding fires regime characteristics.

  5. Diversidad de reptiles en tres tipos de vegetación del estado de Hidalgo, México Diversity of reptiles in three vegetation types of the Hidalgo state, México

    Raciel Cruz-Elizalde

    2012-06-01

    Full Text Available La zona sureste del estado de Hidalgo presenta diversos tipos de vegetación, como el bosque mesófilo de montaña, bosque de pino-encino y bosque de pino, con alta riqueza de reptiles. En este estudio, se analizó la diversidad alfa y beta de los reptiles en los 3 tipos de vegetación presentes en la zona sureste. Durante el periodo de recolección, de junio 2008 a agosto del 2009, se realizaron 12 salidas, 1 por mes, con duración de 3 días cada una. La diversidad de reptiles está compuesta por 25 especies, incluyendo un registro nuevo para el estado, la culebra Thamnophis scaliger. El bosque mesófilo de montaña (BMM presentó la mayor riqueza, con 15 especies, seguido del bosque de pino (BP, con 13, y el bosque de pino-encino (BPE, con 12. Las asociaciones realizadas entre el BMM-BP y BMM-BPE presentaron la más alta disimilitud en especies, y el menor valor fue para el BPE-BP. Este estudio muestra la riqueza y distribución de las especies de los reptiles en los diferentes tipos de vegetación del sureste del estado y presenta nuevos registros de especies para la entidad. El conocimiento de la riqueza de especies por tipos de vegetación de este estudio sienta las bases sobre la biodiversidad, lo que ayuda a plantear estudios dirigidos a la conservación de este grupo.The southeast of Hidalgo in Mexico includes various vegetation types, such as cloud forest, pine-oak forest and pine forest, all harbouring a high species richness of reptiles. In this study we analyzed the alpha and beta diversity of reptiles in 3 vegetation types in the southeast of the state. The field work period was from June 2008 to August 2009, comprising 12 sampling periods of 3 days, 1 per month. The diversity of reptiles is composed of 25 species, reporting the snake Thamnophis scaliger as a new record for the state. The cloud forest (CF has the highest richness, with 15 species, followed by pine forest (PF, with 13, and finally, the pine-oak forest (POF, with 12

  6. Dutch Vegetation Database (LVD)

    Hennekens, S.M.

    2011-01-01

    The Dutch Vegetation Database (LVD) hosts information on all plant communities in the Netherlands. This substantial archive consists of over 600.000 recent and historic vegetation descriptions. The data provide information on more than 85 years of vegetation recording in various habitats covering te

  7. Vegetation inventory, mapping, and classification report, Fort Bowie National Historic Site

    Studd, Sarah; Fallon, Elizabeth; Crumbacher, Laura; Drake, Sam; Villarreal, Miguel

    2013-01-01

    ephemeral washes dominated by Ash (Fraxinus), Walnut (Juglans) and Hackberry (Celtis) to drier upland sites typical of desert scrub and semi-desert grassland communities. These shrublands boast a diverse mixture of shrubs, succulents and perennial grasses. In many places the vegetation could be seen to echo the history of the fort site, with management of shrub encroachment apparent in the grasslands and the paucity of trees evidence of historic cutting for timber and fire wood. Seven of the 16 vegetation types were ‘accepted’ types within the NVC while the others have been described here as specific to FOBO and have proposed status within the NVC. The map was designed to facilitate ecologically-based natural resources management and research. The map is in digital format within a geodatabase structure that allows for complex relationships to be established between spatial and tabular data, and makes accessing the product easy and seamless. The GIS format allows user flexibility and will also enable updates to be made as new information becomes available (such as revised NVC codes or vegetation type names) or in the event of major disturbance events that could impact the vegetation.

  8. Contrast in vegetation net primary productivity estimation models and ecological effect value evaluation in Northwest China%西北地区植被净初级生产力估算模型对比与其生态价值评价

    任志远; 刘焱序

    2013-01-01

    净初级生产力(NPP)是绿色植物在单位时间和单位面积上所能产生的有机干物质总量,是地球碳氧循环研究的关键问题之一.通过使用不同模型进行NPP物质量测算并换算为价值量,分析2000-2009年西北地区NPP价值的时空分异特征,了解西北地区近年植被生态效应的变化格局与趋势.结果表明:(1) CASA模型估算出耕地、草地、常绿针叶林的平均NPP分别为4.15 t·hm-2、4.87 t·hm-2和7.35 t·hm-2,统计模型中综合模型与北京模型和CASA模型估算结果最为相近;(2)研究区NPP价值随时间序列递增,耕地与建设用地的增幅集中在2000-2003年,而草地与未利用地增幅集中于2006-2009年,草地增长最快,2009年达7.91×107万元;(3)以县域为单元分析NPP价值空间差异,空间分布的不对称性、趋向均值的偏离程度有所增加,但高值集聚特征也有所加强;(4) NPP价值的空间集聚变化有低值快速升高、高值继续升高、较高值出现下降3种趋势,青藏高原与黄土高原NPP价值增速最快.NPP价值升高趋势比下降趋势更明显,反映了西北地区生态环境呈现整体好转、局部恶化的态势.%Net primary productivity (NPP) is the total dry organic matter produced by green plants in unit time and area. It is one of the key parameters used in carbon and oxygen cycle research. Not much NPP research has covered the whole of Northwest China and model estimates of NPP have also varied considerably. Photosynthesis is the main mode vegetation generates dry mater and is the core link between natural carbon and oxygen cycles. The synthesis of NPP is accompanied by energy fixing, carbon sinking and oxygen production; which are three indispensable ecological processes for human survival and development. By estimation of NPP based on photosynthetic equation, ecological effects via the synthesis of NPP can be effectively and quantitatively evaluated. This study compared different NPP

  9. Nest success and reproductive ecology of the Texas Botteri’s Sparrow (Peucaea botterii texana) in exotic and native grasses

    Miller, Katherine S.; McCarthy, Erin M.; Woodin, Marc C.; Withers, Kim

    2013-01-01

    Very little information is available for Peucaea botterii texana (Texas Botteri’s Sparrow) and nothing is known about its nesting ecology, in part due to its cryptic behavior and nesting strategies. Our goal was to examine the nesting ecology of Texas Botteri’s Sparrows and compare reproductive success between exotic and native grass- lands. We searched for and monitored nests in 2004 and 2005 on the King Ranch in southern Texas. We found no relationship in reproductive effort, nest characteristics, and plant species richness around the nest between grassland types. Vegetation surrounding Texas Botteri's Sparrow nests was significantly taller and denser in native grasslands than in exotic grasslands. Further research on nesting ecology for the Texas Botteri’s Sparrow is necessary to determine its habitat needs and its role as an indicator of grassland quality.

  10. Rock vegetation types of Danxia landform in Zhejiang Province%浙江省丹霞地貌岩生植被类型

    沈年华; 李传磊; 王小德

    2011-01-01

    Rock vegetation of Danxia landform in Zhejiang Province consists of 5 categories, namely, shrub, shrub-grassland, meadow, vine and moss. Shrubs include Spiraea blumei, Exochorda racemosa, Vitex negundo var. Cannabifolia and Lagerstroemia indie a. Shrub-grasslands include Celtis biondii-Conandron ramondioides, Lespedeza bicolor-Neyraudia montana and Lespedeza bicolor-Sedum alfredii. Meadows include Neyraudia montana, Orostachys erubescens-Sedum polytrichoides, Conandron ramondioides, Selaginella moellendorffii, Pyrrosia lingua and Drynaria fortunei. Vines include Trachelospermum jasminoides, Ficus pumila and Parthenocissus tricuspidata. Mosses include Pogonatum inflexion, Campylopus umbellatus, Philonotis turneriana -Campylopus umbellatus and Bryum argenteum-Sematophyllum subhumile.%浙江省丹霞地貌岩生植被由灌丛、灌草丛、草甸、藤本和苔藓等5种类型组成.其中,灌丛有绣球绣线菊Spiraeab lumei灌丛、白鹃梅Exochorda racemosa灌丛、牡荆Vitex negundo vat.cannabifoli灌丛和紫薇Lagerstroemia indica灌丛;灌草丛有紫弹朴Celtis biondii-苦苣苔Conandron ramondioides灌草丛、胡枝子Lespedeza bicolor-山类芦Neyraudia montana灌草丛和小蜡Lespedeza bicolor-东南景天Sedum alfredii灌草丛;草甸有山类芦草甸、晚红瓦松Orostachys erubescens-藓状景天Sedum polytrichoides草甸、苦苣苔草甸、江南卷柏Selaginella moellendorffii草甸、石韦Pyrrosia lingua草甸和槲蕨Drynaria fortunei草甸;藤本类型有络石Trachelospermum jasminoides,薜荔Ficus pumila和爬山虎Parthenocissus tricuspidata;苔藓类型有东亚小金发藓Pogonatum inflexum,节茎曲柄藓Campylopus umbellatus、东亚泽藓Philonotis turneriana-节茎曲柄藓Campylopus umbellatus和真藓Bryum argenteum-矮锦藓Sematophyllum subhumile等.

  11. 基于 SolidWorks 的果蔬采摘基本构型库的设计%Design of Fruit and Vegetable Picking Mechanism Type Library System Based on Solidworks Software

    夏红梅; 李志伟; 甄文斌; 赖基平

    2013-01-01

      少自由度串、并联机构构型是果蔬采摘机构构型综合的基本单元。为此,基于SolidWorks2008软件,采用尺寸驱动的设计方法,开发了少自由度串并联基本构型库系统。通过建立基本构型三维模型模板,创建机构性能属性信息数据库,利用VisualC++设计系统交互界面,编写API和ADO接口程序,实现基本机构构型参数化设计和属性信息查询修改功能,为果蔬采摘机构构型智能、高效和高质量综合提供设计资源平台。%Low-mobility serial or parallel mechanism is the basic unit for fruit and vegetable picking mechanism structur -al synthesis .Based on Solidworks 2008 software , low-mobility serial or parallel mechanism type library was developed by dimension driven design method .The basic mechanism type library system architecture was put forward .Through estab-lishing three-dimensional model template for basic mechanisms , creating mechanism performance data attribute informa-tion table , designing system interface with Visual C++software , writing API and ADO interface program , parameter de-sign and attribute information query modification function for basic mechanisms was realized .An intelligent , efficient , high quality design resource platform for fruit and vegetable picking mechanism structural synthesis was developed in the paper .

  12. Field-testing ecological and economic benefits of coffee certification programs.

    Philpott, Stacy M; Bichier, Peter; Rice, Robert; Greenberg, Russell

    2007-08-01

    Coffee agroecosystems are critical to the success of conservation efforts in Latin America because of their ecological and economic importance. Coffee certification programs may offer one way to protect biodiversity and maintain farmer livelihoods. Established coffee certification programs fall into three distinct, but not mutually exclusive categories: organic, fair trade, and shade. The results of previous studies demonstrate that shade certification can benefit biodiversity, but it remains unclear whether a farmer's participation in any certification program can provide both ecological and economic benefits. To assess the value of coffee certification for conservation efforts in the region, we examined economic and ecological aspects of coffee production for eight coffee cooperatives in Chiapas, Mexico, that were certified organic, certified organic and fair trade, or uncertified. We compared vegetation and ant and bird diversity in coffee farms and forests, and interviewed farmers to determine coffee yield, gross revenue from coffee production, and area in coffee production. Although there are no shade-certified farms in the study region, we used vegetation data to determine whether cooperatives would qualify for shade certification. We found no differences in vegetation characteristics, ant or bird species richness, or fraction of forest fauna in farms based on certification. Farmers with organic and organic and fair-trade certification had more land under cultivation and in some cases higher revenue than uncertified farmers. Coffee production area did not vary among farm types. No cooperative passed shade-coffee certification standards because the plantations lacked vertical stratification, yet vegetation variables for shade certification significantly correlated with ant and bird diversity. Although farmers in the Chiapas highlands with organic and/or fair-trade certification may reap some economic benefits from their certification status, their farms may

  13. Relationship Between Agriculture and Ecological Deterioration, Restoration and Reconstruction in Loess Plateau Areas of Northwest China

    CHENG Xu

    2002-01-01

    A comprehensive analysis was conducted on the current situation as well as historic succession process of agriculture and ecological conditions in Northwest China, in particular in the Loess Plateau, by means of a inter-disciplinary approach of ecology, agro-geohistory, and agronomy. It was concluded that the fundamental causes responsible for the ecological deterioration, signed by the poor agro-productivity and serious soil erosion, had been the extensive cropping system by ever-increasing reclamation on semi-drought slope land, where initiated a natural vegetation of brushy grasses with sparse trees, thus suitable only for animal husbandry. Based on an identification of specific actual status of China, several countermeasures of correctly dealing with the relationship between agricultural development and the ecological restoration and reconstruction were proposed, including to get breakthrough first in the transection area by means of the rational use of resources and the raising of agro-system productivity, to promoting "water conservancy-type ecological agriculture" through the radical shift of traditional production pattern, and the adoption of a policy of proper degree of grain self-reliance, as well as to construct livestock industry base in Northwest China.

  14. Analysis of the vegetation of the sandstone ridges (Ib land type of the north-eastern parts of the Mapungubwe National Park, Limpopo Province, South Africa

    Albie R. Gotze

    2008-05-01

    Full Text Available The establishment of the Mapungubwe National Park has been an objective of several conservationists for many years. The ultimate objective is that this park should become a major component of a Transfrontier National Park shared by Botswana, Zimbabwe and South Africa. The aim of this study was to identify, classify and describe the plant communities present in the Ib land type of the park. Sampling was done by means of the Braun-Blanquet method. A total of 48 stratified random relevés were sampled in the Ib land type. All relevé data were imported into a TURBOVEG database, after which the numerical classification technique TWINSPAN was used as a first approximation. Subsequently, Braun-Blanquet procedures were used to refine data and a phytosociological table was constructed, using the visual editor, MEGATAB. Two plant communities and several subcommunities and variants were identified and described from the phytosociological table.

  15. Ecological macroeconomics

    Røpke, Inge

    2013-01-01

    of this discussion includes contributions from actors involved with efforts to advance a ‘Green New Deal’ that repeats the idea that the promotion of green innovation and government funding of greener infrastructure would improve competitiveness and increase employment. This time ‘Green Keynesianism’ is accompanied...... to shift resources from consumption to investment and describing the role of consumer-citizens in such a change. The chapter starts by identifying the problems and challenges for an ecological macroeconomics. The next section outlines some of the shortcomings of traditional macroeconomics...... to energy, transport, housing, food and so forth. The fourth section outlines briefly the roles of consumer-citizens in relation to such sustainability transformations and the final section considers the possibilities for initiating the envisioned changes....

  16. Vegetation of eastern Unalaska Island, Aleutian Islands, Alaska

    Talbot, Stephen S.; Schofield, Wilfred B.; Talbot, Sandra L.; Daniëls, Fred J. A.

    2010-01-01

    Plant communities of Unalaska Island in the eastern Aleutian Islands of western Alaska, and their relationship to environmental variables, were studied using a combined Braun-Blanquet and multivariate approach. Seventy relevés represented the range of structural and compositional variation in the matrix of vegetation and landform zonation. Eleven major community types were distinguished within six physiognomic–ecological groups: I. Dry coastal meadows: Honckenya peploides beach meadow, Leymus mollis dune meadow. II. Mesic meadows: Athyrium filix-femina – Aconitum maximum meadow, Athyrium filix-femina – Calamagrostis nutkaensis meadow, Erigeron peregrinus – Thelypteris quelpaertensis meadow. III. Wet snowbed meadow: Carex nigricans snowbed meadow. IV. Heath: Linnaea borealis – Empetrum nigrum heath, Phyllodoce aleutica heath, Vaccinium uliginosum – Thamnolia vermicularis fellfield. V. Mire: Carex pluriflora – Plantago macrocarpa mire. VI. Deciduous shrub thicket: Salix barclayi – Athyrium filix-femina thicket. These were interpreted as a complex gradient primarily influenced by soil moisture, elevation, and pH. Phytogeographical and syntaxonomical analysis of the plant communities indicated that the dry coastal meadows, most of the heaths, and the mire vegetation belonged, respectively, to the widespread classes Honckenyo–Elymetea, Loiseleurio–Vaccinietea, and Scheuchzerio–Caricetea, characterized by their circumpolar and widespread species. Amphi-Beringian species were likely diagnostic of amphi-Beringian syntaxa, many of these yet to be described.

  17. Assessment of the environmental effects of mining using SPOT-Vegetation NDVI

    Tote, C.; Swinnen, E.; Goossens, M.; Reusen, I.; Delalieux, S.

    2012-04-01

    Within the ImpactMin project, funded by the Framework Programme 7 of the European Commission, new methods for the environmental impact monitoring of mining operations are being developed. The objective of this study is to analyze the impact of mining on soil properties through assessment of the vegetation status using time series analysis of low resolution Normalized Difference Vegetation Index (NDVI) images derived from SPOT-Vegetation. The study focuses on the surroundings of mining areas in the Orenburg region in the Russian Urals. Karabash has been a centre for mining and metal production for well over 3000 years, and environmental impact of (historical) mining in the area is extremely severe. The area was characterized as an 'ecological disaster zone', based on chemical analysis of soil samples in the area [1]. The mining activities were intensified in the early to mid-20th century, but the old smelter was modernized in the 1990s. A time series of 10-daily NDVI images from SPOT-Vegetation (S10 April/1998-December/2010 at 1km2 resolution, http://www.vgt.vito.be/) is analyzed. Different land cover types clearly show different phenology. To remove seasonal vegetation changes and thus to facilitate the interpretation through the historical record, a Standardized Difference Vegetation Index (SDVI) was calculated for each pixel and for each record of the time series. The first results of trend analyses indicate a strong recovery of open forests in the Karabash region in the last decade. To what extent this can be related to reduced mining impact or climate factors, still needs to be assessed. Further research will also focus on the spatial heterogeneity of phenological parameters, in relation to distance to and wind direction of the smelters and soil properties. [1] V. Nestersnko, "Urban associations of elements- environmental pollutants in Karabash city (Chelyabinsk oblast) as a reflection of ore-chemical descriptions of mineral raw material", Proceedings of the

  18. Integrating field sampling, geostatistics and remote sensing to map wetland vegetation in the Pantanal, Brazil

    Arieira, J.; Karssenberg, D.; de Jong, S. M.; Addink, E. A.; Couto, E. G.; Nunes da Cunha, C.; Skøien, J. O.

    2011-03-01

    Development of efficient methodologies for mapping wetland vegetation is of key importance to wetland conservation. Here we propose the integration of a number of statistical techniques, in particular cluster analysis, universal kriging and error propagation modelling, to integrate observations from remote sensing and field sampling for mapping vegetation communities and estimating uncertainty. The approach results in seven vegetation communities with a known floral composition that can be mapped over large areas using remotely sensed data. The relationship between remotely sensed data and vegetation patterns, captured in four factorial axes, were described using multiple linear regression models. There were then used in a universal kriging procedure to reduce the mapping uncertainty. Cross-validation procedures and Monte Carlo simulations were used to quantify the uncertainty in the resulting map. Cross-validation showed that accuracy in classification varies according with the community type, as a result of sampling density and configuration. A map of uncertainty derived from Monte Carlo simulations revealed significant spatial variation in classification, but this had little impact on the proportion and arrangement of the communities observed. These results suggested that mapping improvement could be achieved by increasing the number of field observations of those communities with a scattered and small patch size distribution; or by including a larger number of digital images as explanatory variables in the model. Comparison of the resulting plant community map with a flood duration map, revealed that flooding duration is an important driver of vegetation zonation. This mapping approach is able to integrate field point data and high-resolution remote-sensing images, providing a new basis to map wetland vegetation and allow its future application in habitat management, conservation assessment and long-term ecological monitoring in wetland landscapes.

  19. Resilience Through Disturbance: Effects of Wildfire on Vegetation and Water Balance in the Sierra Nevadas

    Boisrame, G. F. S.; Thompson, S. E.; Stephens, S.; Collins, B.; Tague, N.

    2015-12-01

    A century of fire suppression in the Western United States has drastically altered the historically fire-adapated ecology in California's Sierra Nevada Mountains. Fire suppression is understood to have increased the forest cover, as well as the stem density, canopy cover and water demand of montane forests, reducing resilience of the forests to drought, and increasing the risk of catastrophic fire by drying the landscape and increasing fuel loads. The potential to reverse these trends by re-introducing fire into the Sierra Nevada is highly promising, but the likely effects on vegetation structure and water balance are poorly quantified. The Illilouette Creek Basin in Yosemite National Park represents a unique experiment in the Sierra Nevada, in which managers have moved from fire suppression to allowing a near-natural fire regime to prevail since 1972. Changes in vegetation structure in the Illilouette since the restoration of natural burning provides a unique opportunity to examine how frequent, mixed severity fires can reshape the Sierra Nevada landscape. We characterize these changes from 1969 to the present using a combination of Landsat products and high-resolution aerial imagery. We describe how the landscape structure has changed in terms of vegetation composition and its spatial organization, and explore the drivers of different post-fire vegetation type transitions (e.g. forest to shrubland vs. forest to meadow). By upscaling field data using vegetation maps and Landsat wetness indices, we explore how these vegetation transitions have impacted the water balance of the Illilouette Creek Basin, potentially increasing its resilience in the face of drought, climate change, and catastrophic fire. In a region that is adapted to frequent disturbance from fire, this work helps us understand how allowing such natural disturbances to take place can increase the sustainability of diverse landscapes in the long term.

  20. The effects of vegetation cover on soil nematode communities in various biotopes disturbed by industrial emissions.

    Šalamún, Peter; Hanzelová, Vladimíra; Miklisová, Dana; Šestinová, Oľga; Findoráková, Lenka; Kováčik, Peter

    2017-08-15

    Better understanding of interactions among belowground and aboveground components in biotopes may improve our knowledge about soil ecosystem, and is necessary in environment assessment using indigenous soil organisms. In this study, we proposed that in disturbed biotopes, vegetation play important role in the buffering of contamination impact on soil communities and decrease the ecological pressure on soil biota. To assess the effects of these interactions we compared nematode communities, known for their bioindication abilities, from four types of disturbed and undisturbed biotopes (coniferous forest, permanent grassland, agricultural field, clearings), where the main stress agent was represented by long-term acidic industrial emissions containing heavy metals (As, Cd, Cu, and Pb). To understand the ecological interactions taking place in studied biotopes, we studied abiotic factors (soil properties) and biotic factors (vegetation, nematode communities). Except significant increase in metals total and mobile concentrations in disturbed biotopes soil, we found acidification of soil horizon, mainly in the clearings (pH=3.68), due to SO2 precipitation. These factors has caused in clearings degradation of native phytocoenoses and decrease in decomposition rate characterized by high amount of organic matter (Cox=4.29%). Nematodes reacts to these conditions by shifts in trophic structure (bacteriovores to fungal feeders), increase in c-p 2 genera (Aphelenchoides, Acrobeloides, and Cephalobus), absence of sensitive groups (c-p 3-5, omnivores, predators), and decrease in ecological indices (SI, MI, MI2-5, H'). Similar contamination was found in forest biotope, but the nematodes composition indicates more suitable conditions; more complex community structure (presence of sensitive trophic and higher c-p groups), higher abundance and indices values, comparable with less stressed field and grassland biotopes. As showed our results, the vegetation undoubtedly plays an

  1. Catálogo de los ejemplares tipo de peces depositados en la colección del Laboratorio de Ecología del Departamento de Zoología, ENCB, IPN Catalogue of fish types housed at Colección del Laboratorio de Ecología del Departamento de Zoología, ENCB, IPN

    Ana Fabiola Guzmán

    2011-08-01

    Full Text Available Se presenta la información de los ejemplares tipo de peces actinopterigios depositados en la colección del Laboratorio de Ecología, de la Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, de acuerdo a la recomendación 72F del Código Internacional de Nomenclatura Zoológica. La información fue documentada con base en el análisis bibliográfico de las descripciones originales, los diccionarios, catálogos, etiquetas y ejemplares en cuestión. Los tipos corresponden a holotipos y paratipos y designan a seis especies, dos géneros y una familia. Cuatro de los seis nombres de especie son válidos y uno más se usa bajo una nueva combinación.Information regarding type specimens of actinopterygian fishes housed at Laboratorio de Ecología, Escuela Nacional de Ciencias Biológicas-IPN, is provided. This information follows the International Code of Zoological Nomenclature recommendation 72F. Data were documented based on the analysis of original descriptions, dictionaries, catalogues, labels and specimens themselves. The types comprise holotypes and paratypes, which correspond to six species, two genera, and 1 family names. Four of the six species names are still valid and one is used under a new combination.

  2. Long-term protection effects of national reserve to forest vegetation in 4 decades: Biodiversity change analysis of major forest types in Changbai Mountain Nature Reserve, China

    BAI Fan; SANG WeiGuo; LI GuangQi; LIU RuiGang; CHEN LingZhi; WANG Kun

    2008-01-01

    The Changbai Mountain Nature Reserve (CNR) was established in 1960 to protect the virgin Korean pine mixed hardwood forest, a typical temperate forest of northeast China. We conducted systematic stud-ies of vascular diversity patterns on the north slope of the CNR mountainside forests (800-1700 m a.s.I.) in 1963 and 2006 respectively. The aim of this comparison is to assess the long-term effects of the protection on plant biodiversity of CNR during the interval 43 years. The research was carried out in three types of forests: mixed coniferous and broad-leaved forest (MCBF), mixed coniferous forest (MCF), and sub-alpine coniferous forest (SCF), characterized by different dominant species. The alpha diversity indicted by species richness and the Shannon-Wiener index were found different in the same elevations and forest types during the 43-year interval. The floral composition and the diversity of vascular species were generally similar along altitudinal gradients before and after the 43-year interval, but some substantial changes were evident with the altitude gradient. In the tree layers, the dominant species in 2006 were similar to those of 1963, though diversity declined with altitude. The indices in the three forest types did not differ significantly between 1963 and 2006, and these values even increased in the MCBF and MCF from 1963 to 2006. However, originally dominant species, P. koraiensis for ex-ample, tended to decline, while the proportion of broad-leaved trees increased, and the species turn-over in the succession layers trended to shift to higher altitudes. The diversity pattern of the under canopy fluctuated along the altitudinal gradient due to micro-environmental variations. Comparison of the alpha diversity in the three forests shows that the diversity of the shrub and herb layer decreased with time. During the process of survey, we also found some rare and medicinal species disappeared. Analysis indicates that the changes of the diversity pattern

  3. Long-term protection effects of national reserve to forest vegetation in 4 decades: biodiversity change analysis of major forest types in Changbai Mountain Nature Reserve, China

    2008-01-01

    The Changbai Mountain Nature Reserve (CNR) was established in 1960 to protect the virgin Korean pine mixed hardwood forest, a typical temperate forest of northeast China. We conducted systematic stud- ies of vascular diversity patterns on the north slope of the CNR mountainside forests (800-1700 m a.s.l.) in 1963 and 2006 respectively. The aim of this comparison is to assess the long-term effects of the protection on plant biodiversity of CNR during the interval 43 years. The research was carried out in three types of forests: mixed coniferous and broad-leaved forest (MCBF), mixed coniferous forest (MCF), and sub-alpine coniferous forest (SCF), characterized by different dominant species. The alpha diversity indicted by species richness and the Shannon-Wiener index were found different in the same elevations and forest types during the 43-year interval. The floral composition and the diversity of vascular species were generally similar along altitudinal gradients before and after the 43-year interval, but some substantial changes were evident with the altitude gradient. In the tree layers, the dominant species in 2006 were similar to those of 1963, though diversity declined with altitude. The indices in the three forest types did not differ significantly between 1963 and 2006, and these values even increased in the MCBF and MCF from 1963 to 2006. However, originally dominant species, P. koraiensis for ex- ample, tended to decline, while the proportion of broad-leaved trees increased, and the species turn- over in the succession layers trended to shift to higher altitudes. The diversity pattern of the under canopy fluctuated along the altitudinal gradient due to micro-environmental variations. Comparison of the alpha diversity in the three forests shows that the diversity of the shrub and herb layer decreased with time. During the process of survey, we also found some rare and medicinal species disappeared. Analysis indicates that the changes of the diversity

  4. Long-term protection effects of National Reserve to forest vegetation in 4 decades: biodiversity change analysis of major forest types in Changbai Mountain Nature Reserve, China.

    Bai, Fan; Sang, WeiGuo; Li, GuangQi; Liu, RuiGang; Chen, LingZhi; Wang, Kun

    2008-10-01

    The Changbai Mountain Nature Reserve (CNR) was established in 1960 to protect the virgin Korean pine mixed hardwood forest, a typical temperate forest of northeast China. We conducted systematic studies of vascular diversity patterns on the north slope of the CNR mountainside forests (800-1700 m a.s.l.) in 1963 and 2006 respectively. The aim of this comparison is to assess the long-term effects of the protection on plant biodiversity of CNR during the interval 43 years. The research was carried out in three types of forests: mixed coniferous and broad-leaved forest (MCBF), mixed coniferous forest (MCF), and sub-alpine coniferous forest (SCF), characterized by different dominant species. The alpha diversity indicted by species richness and the Shannon-Wiener index were found different in the same elevations and forest types during the 43-year interval. The floral composition and the diversity of vascular species were generally similar along altitudinal gradients before and after the 43-year interval, but some substantial changes were evident with the altitude gradient. In the tree layers, the dominant species in 2006 were similar to those of 1963, though diversity declined with altitude. The indices in the three forest types did not differ significantly between 1963 and 2006, and these values even increased in the MCBF and MCF from 1963 to 2006. However, originally dominant species, P. koraiensis for example, tended to decline, while the proportion of broad-leaved trees increased, and the species turnover in the succession layers trended to shift to higher altitudes. The diversity pattern of the under canopy fluctuated along the altitudinal gradient due to micro-environmental variations. Comparison of the alpha diversity in the three forests shows that the diversity of the shrub and herb layer decreased with time. During the process of survey, we also found some rare and medicinal species disappeared. Analysis indicates that the changes of the diversity pattern in

  5. Survey of ecological resources at selected US Department of Energy sites

    McAllister, C.; Beckert, H.; Abrams, C. [and others

    1996-09-01

    The U.S. Department of Energy (DOE) owns and manages a wide range of ecological resources. During the next 30 years, DOE Headquarters and Field Offices will make land-use planning decisions and conduct environmental remediation and restoration activities in response to federal and state statutes. This document fulfills, in part, DOE`s need to know what types of ecological resources it currently owns and manages by synthesizing information on the types and locations of ecological resources at 10 DOE sites: Hanford Site, Idaho National Engineering Laboratory, Lawrence Livermore National Laboratory, Sandia National Laboratory, Rocky Flats Plant, Los Alamos National Laboratory, savannah River Site, Oak Ridge National Laboratory, Argonne National Laboratory, and Fernald Environmental Management Project. This report summarizes information on ecosystems, habitats, and federally listed threatened, endangered, and candidate species that could be stressed by contaminants or physical activity during the restoration process, or by the natural or anthropogenic transport of contaminants from presently contaminated areas into presently uncontaminated areas. This report also provides summary information on the ecosystems, habitats, and threatened and endangered species that exist on each of the 10 sites. Each site chapter contains a general description of the site, including information on size, location, history, geology, hydrology, and climate. Descriptions of the major vegetation and animal communities and of aquatic resources are also provided, with discussions of the treatened or endangered plant or animal species present. Site-specific ecological issues are also discussed in each site chapter. 106 refs., 11 figs., 1 tab.

  6. Contrasting total carbon and nitrogen stocks between ecological site types in a Sub-Boreal research forest in central British Columbia

    Bois, C.H.; Janzen, D.T. [Northern British Columbia Univ., Prince George, BC (Canada). Ecosystem Science and Management Program; Sanborn, P.T.; Fredeen, A.L. [Northern British Columbia Univ., Prince George, BC (Canada). Ecosystem Science and Management Program]|[Northern British Columbia Univ., Prince George, BC (Canada). Natural Resources and Environmental Studies Inst.

    2006-07-01

    Carbon (C) sequestration and carbon stocks within managed and natural forests have become topical issues since the adoption of the Kyoto Protocol. A multi-year study was conducted to evaluate the total C stocks present in a 10 km{sup 2} area of University of British Columbia's Aleza Lake Research Forest located 60 km east of Prince George in the Sub-Boreal Spruce biogeoclimatic zone of east-central British Columbia. The purpose was to address gaps in knowledge about forest C budgets, total pool sizes, dynamics of forest floor and mineral soil carbon by studying the effects of forest management. Sampling plots were chosen randomly within strata composed of the dominant ecological site classes, soil textures and management histories. The study involved the creation of 137 plots, of which 108 and 29 were located on fine and coarse textured soils, respectively. Sampling was reduced in these strata due to a shortage of middle-aged stands and the near lack of coarse textured soils. Data collection and sampling methodology were adapted from the National Forest Inventory Ground Sampling Guidelines of the Canadian Forest Service. Carbon stocks were measured in forest floor and mineral soil to a depth of 1 metre. The Dumas-combustion method was used to determine C and nitrogen (N) concentrations. It was determined that stand age did not decidedly change the forest floor or mineral soil total C and N in either fine or coarse textured soil plots. However, forest floor C and N were considerably higher in coarse textured soils compared to C and N measured in fine soil plots. Mineral soil C concentration decreased methodically with depth from 4.6 per cent C at 0 cm to 0.2 per cent at 100 cm. The paper also addressed the breakdown of forest floor and mineral soil C and N pools according to ecological site series.

  7. Relationship between Ecological Species Groups and Environmental Factors (Case Study: Vezg Region in Southeast of Yasouj

    R. Aghaei

    2013-03-01

    Full Text Available In applied studies, identification and study of vegetation, for management and protection of natural ecosystems, are very important. This study was carried out in Vezg forest with an area of 308 hectares located in southeast of Yasouj city. The purpose of this study was to classify ecological species groups and survey their relation to soil physic-chemical properties and physiographic attributes. For this purpose, the field data were obtained using 52 sample plots (15m×30m in a systematic random grid. In each sample plot, the cover percentage of tree, shrub and grass species type were recorded, by using Braun-Blanquet method. The TWINSPAN method and Canonical Correspondence Analysis (CCA were used for the definition of ecological species groups and determintion of the relationship between ecological species groups and environmental properties. Results showed that, there were four ecological species groups in the study area. The First group included: Anchusa italic-Quercus brantii, the second group: Heteranthelium piliferum-Avena clauda, the third group: Teucrium polium and the fourth group: Salvia reautreana. The first group was in an area, where there was a higher percentage of Persian oak litter. The second group was located in site a with higher grass cover than the site of other groups in the area. The third and fourth groups, were located in the higher elevation and steep points. Results of CCA showed that soil properties were not in significant relation with ecological species groups. But, the relationships of ecological species groups with other environmental factors such as litter, altitude, grass cover and slope were significant. So, we can conclude that these properties are effective in the separation and distribution of ecological groups.

  8. Distribution and ecological consequences of ploidy variation in Artemisia sieberi in Iran

    Jalili, Adel; Rabie, Mina; Azarnivand, Hossein; Hodgson, John G.; Arzani, Hossein; Jamzad, Ziba; Asri, Younes; Hamzehee, Behnam; Ghasemi, Farzaneh; Hesamzadeh Hejazi, S. M.; Abbas-Azimi, R.

    2013-11-01

    Because of their high proportion in the plant kingdom polyploid taxa are considered to have had evolutionary advantages over their diploid ancestors. These advantages may have included new characteristics that enable polyploids to occupy a broader range of habitats. In this context, we assess the ecological range of Artemisia sieberi, a canopy dominant within an important vegetation type in Iran. We assess the extent to which ploidy covaries with geographical and ecological distribution and look for ecologically-significant differences in the functional characteristics of diploids and polyploids. Populations of A. sieberi were sampled widely in Iran and soil characteristics, climate and anatomical and phytochemical plant attributes were measured. Also, in parallel, an independent genetic assessment of populations was carried out using genetic fingerprinting. Two ploidy levels were identified: 75% of the 34 populations of A. sieberi populations sampled were tetraploid (2n = 4x = 36) with the remainder diploid (2n = 2x = 18). Plants of differing ploidy also differed anatomically, genetically and chemically. Tetraploid populations had larger cells and lower stomatal densities and a different essential oil composition. They also appear ecologically distinct, occupying more fertile, mesic habitats than diploids. Genetic fingerprinting revealed the existence of two genetically differentiated subgroups independent of ploidy but with some geographic and ecological pattern. We conclude that diploids and tetraploids have a different ecological distribution and that the absence of mixed diploid-tetraploid populations is a reflection of differing fitness in different habitats. We suspect that a key ecological difference between diploids and tetraploids is the increased stomatal size of tetraploids, possibly resulting from the increased genome and hence cell size following polyploidisation. Polyploid-formation may be constrained in arid habitats by problems of water

  9. Management pattern of ecological public welfare forests in South China

    Chong LOU; Anxing LIU; Guomin ZHU

    2008-01-01

    The characteristics and actualities of ecologi-cal public welfare forests in South China are studied in this paper, including common and special management patterns. The restoration and reconstruction pattern of subtropical evergreen broad-leaved forests, zonal vegeta-tion in the key eco-zone, and the transformation pattern of coniferous and broad-leaved mixed forests in the general eco-zone with multi-forms are discussed in detail. The authors also point out, based on ecological transformation and utilization, that ecological public welfare forests should be oriented to multiple benefit utilization to maintain sustainable management.

  10. Vegetation factors influencing density and distribution of wild large herbivores in a southern African savannah

    Gandiwa, E.

    2014-01-01

    Understanding factors influencing large herbivore densities and distribution in terrestrial ecosystems is a fundamental goal of ecology. This study examined environmental factors influencing the density and distribution of wild large herbivores in Gonarezhou National Park, Zimbabwe. Vegetation and s

  11. Significant variation in vegetation characteristics and dynamics from ecohydrological optimality of net carbon profit

    Dekker, S.C.; Vrugt, J.A.; Elkington, R.J.

    2012-01-01

    Recent contributions to the ecological literature have questioned the continued usefulness of the classical model calibration paradigm in estimating parameters in coupled ecohydrological models. Schymanski (2007) and Schymanski et al. (2007, 2008) have demonstrated that the assumption of vegetation

  12. The Research of Ecology-Oriented Reasonable Deployment of Water Resources at Shuangtaizi Estuary Wetland

    LU Xiaofeng; WANG Tieliang; SU Fangli; ZHOU Linfei; LI Bo

    2011-01-01

    Shuangtaizi estuary wetland, the largest natural conservation district in China, and one of the best preserved, largest ecological lands with the most complete vegetation types in the world, is located in Panjin city, Liaoning Province. In rccent years,the degradation of Shuangtaizi estuary wetland is very serious. In order to rescue lives in the wetland and protect valuable natural resources, the information system of Shuangtaizi estuary wetland was built with ‘3S' technology, and the minimum, optimum, and maximum eco-environmental water requirements were calculated respectively. Furthermore, for restoring the ecological functions of wetland and preventing wetland degradation, the balance between supply and demand of water resource was analyzed, and an optimal allocation scheme of water resources was proposed based on three kinds of equilibrium.

  13. Wordsworthian Ecology

    朱文宣

    2014-01-01

    Wordsworth devoted himself to the ideal of a harmonious relation between human and nature, between man and soci-ety, between man and the ego. In this sense, Wordsworth improved the development of ecology. This argument will be support-ed by the approach of eco-criticism and Heidegger’s eco-philosophy. And it is supported by the following points.The first part points out that Wordsworth’s love of nature led to his love of man, which was reflected by his care for common people. Part Two shows Wordsworth’s solicitude for dwelling. His notion of dwelling had aspect of poetic dwelling. The harmonious hu-man-nature relationship reveals thee essence of free dwelling. His poetic experiment agreed with Heidegger ’s argument on poet-ic creation. His discussion of free labour was like Heidegger’s interpretation of“merit”. Part Three tells about Wordsworth’s great effort to amend the alienated human nature by treasuring the Child’s nature, imagination and human feelings.In this way, the conclusion can be got:although it would be a huge project to reinterpret Wordsworth with the approaches of eco-criticism and Heidegger’s eco-philosophy, it is still worth making the effort.

  14. Sound Ecologies

    Michelle Duffy

    2010-02-01

    Full Text Available Discussions about what constitutes ‘the rural’ invariably focus on notions of spatial location – of inhabiting spaces apart from that of the metropolitan. Deeply embedded in our images of what it means to be Australian, nonetheless our intellectual framing of ‘the rural’ as something outback and beyond has significant implications for our relations with these spaces. The relatively recent phenomenon of sea- and tree-changes has struck many unawares, and not simply because a good latté is so hard to find. Although a frivolous remark, such an apparent lack does shift our focus to a bodily scale of the rural; how is rural place re/made through our experiences of it? This article originates out of on-going research that explores the practice of listening and sound and the ways in which the body can draw attention to the intuitive, emotional, and psychoanalytical processes of subjectivity and place-making. Drawing on Nigel Thrift’s concept of an ecology of place, I suggest that contemporary heightened concerns with regards to loss and lack in rural Australia has led to a nascent emotional economy – one in which individual and intimate connections to the rural require a rethinking of how we live community and belonging. In such a terrain, what does it mean to be rural?

  15. Integrating field sampling, spatial statistics and remote sensing to map wetland vegetation in the Pantanal, Brazil

    Arieira, J.; Karssenberg, D.; de Jong, S. M.; Addink, E. A.; Couto, E. G.; Nunes da Cunha, C.; Skøien, J. O.

    2010-09-01

    To improve the protection of wetlands, it is imperative to have a thorough understanding of their structuring elements and of the identification of efficient methods to describe and monitor them. This article uses sophisticated statistical classification, interpolation and error propagation techniques, in order to describe vegetation spatial patterns, map plant community distribution and evaluate the capability of statistical approaches to produce high-quality vegetation maps. The approach results in seven vegetation communities with a known floral composition that can be mapped over large areas using remotely sensed data. The relations between remotely sensing data and vegetation patterns, captured in four factorial axes, were formalized mathematically in multiple linear regression models and used in a universal kriging procedure to reduce the uncertainty in mapped communities. Universal kriging has shown to be a valuable interpolation technique because parts of vegetation variability not explained by the images could be modeled as spatially correlated residuals, increasing prediction accuracy. Differences in spatial dependence of the vegetation gradients evidenced the multi-scale nature of vegetation communities. Cross validation procedures and Monte Carlo simulations were used to quantify the uncertainty in the resulting map. Cross-validation showed that accuracy in classification varies according with the community type, as a result of sampling density and configuration. A map of uncertainty resulted from Monte Carlo simulations displayed the spatial variation in classification accuracy, showing that the quality of classification varies spatially, even though the proportion and arrangement of communities observed in the original map is preserved to a great extent. These results suggested that mapping improvement could be achieved by increasing the number of field observations of those communities with a scattered and small patch size distribution; or by

  16. Trepadeiras: florística da Estação Ecológica do Caiuá e chave de identificação vegetativa para espécies do Norte do Estado do Paraná=Climbers: flora of the Caiuá Ecological Station and an identification key for the vegetative species of Northern Paraná State

    Ana Odete Santos Vieira

    2012-04-01

    Full Text Available As trepadeiras são plantas com alta representatividade nas florestas tropicais e de grande importância ecológica, apontadas como um dos fatores básicos que diferencia florestas tropicais de temperadas. Este trabalho apresenta as espécies de trepadeiras da Estação Ecológica do Caiuá (EECAIUÁ, município de Diamante do Norte, Estado do Paraná, inserida na floresta estacional semidecidual (FES submontana, situada à margem do rio Paranapanema. Foram encontradas 17 famílias, 44 gêneros e 53 espécies. As cinco famílias mais ricas em número de espécies perfazem juntas 57% do total encontrado. As trepadeiras herbáceas ocorrem em menor número quando comparadas às lianas, e quanto à estratégia utilizada para ascender, as volúveis são as mais diversas, seguidas pelas de órgãos preensores (gavinhas e escandentes. Uma chave de identificação para famílias, baseada em caracteres vegetativos, foi produzida para as famílias desta localidade com as famílias encontradas em outras duas no Norte do Paraná.Climbers are highly represented in tropical forests and are of great ecological importance, having been identified as one of the key factors that differentiate tropical forests from temperate rainforests. This paper presents the climber species of the Caiuá Ecological Station (EECAIUÁ in the City of Diamante do Norte, Paraná State; the Station is located in a submountainous seasonal semideciduous forest (SSF and is situated on the edge of the Paranapanema river. We found 17 families, 44 genera and 53 species of vines. The five families with the greatest number of species jointly accounted for 57% of the total species found. Herbaceous vines occurred less frequently than did lianas. When considering the climbing strategy used by the species, the graspers were the most diverse, followed by those that had tendrils (scramblers and climbers. An identification key based on vegetative characters of families found in other parts of

  17. Technology Drives Vegetable Industry

    2011-01-01

    @@ Arobot for vegetable planting is able to examine growing conditions, detect disease of the vegetables and pick up the ripe ones through identifying the color; a tomato tree is able to produce up to 3,000kgs of tomatoes; sweet potatoes are growing in the air; fish and vegeta-bles are living together harmoniously...Viewing these, you may doubt that you were in a fancy world.Actually, you are here at the 12th China (Shouguang) International Vegetable Sci-tech Fair.

  18. Monitoring vegetation growth and morphodynamic effects after stream restoration

    Vargas-Luna, Andrés; Crosato, Alessandra; Anders, Niels; Hoitink, Ton; Keesstra, Saskia; Uijttewaal, Wim

    2016-04-01

    Vegetation processes are widely recognized as a key component on the ecological and morphological development of river channels. Moreover, plants reduce flow velocities and bed-shear stresses by increasing the local hydraulic roughness and thus increasing water levels. Therefore, monitoring the vegetation development is an important activity in river management not only for protecting ecological services, but also in flood risk reduction; especially in times of a changing climate. This paper presents the analysis the effects of riparian vegetation growth on the morphology of a lowland restored stream located in The Netherlands, the Lunterse beek. An Unmanned Aerial Vehicle (UAV) was used to obtain aerial imagery at different time steps which was the basis for generating land cover maps with semi-automated image classification. In addition hydrological series and multi-temporal high-resolution bathymetric data allowed analysing river bed morphology and the relevance of seasonality. The UAV campaigns were found a crucial step to ease the vegetation mapping and monitoring. The morphological change observed in this stream, represented by the channel-width adjustment and the cross sectional evolution, is slowed down once vegetation is stablished on the stream. Results of this work show that the vegetation root system assert a strong control on soil stabilization, even during the winter season when the plants biomass is highly reduced. Seasonal variations in plant development appear important only during the first stages of establishment, when vegetation has a low density and, more importantly, a root system that is not fully developed yet.

  19. Vegetation patterns and nature reserve construction in an extremely-arid desert in Anxi, NW China's Gansu Province.

    Liu, Hong-Yan; Xu, Li-Hong; Chen, Chang-Du; Cui, Hai-Ting; Xu, Xing-Ying

    2002-07-01

    Anxi County is located in the northwestern part of the Hexi Corridor in Gansu Province and has the sole national level nature reserve of extremely-arid desert in China. Phytosociological methods (Braun-Blanquet, 1964) are used to classify plant community types in this area. Eleven are distinguished, including six of deserts, four of cases and one transitional type between deserts and cases. Direct gradient analysis (DCA) is employed to correlate the distribution of plant communities to physiogeographic conditions. This study makes clear that water is the most important ecological factor for the distribution of plant species and communities in this area. The effects of water have been demonstrated in different ways. A vegetation gradient from lower altitude to higher altitude in the southern part of the reserve is driven by a precipitation gradient. The effects of the depth of ground water table contribute to the differentiation of vegetation from desert to oasis in the flat area. In a finer scale, the washed gullies have obviously higher species richness and also higher vegetation cover than the surround gobi surfaces, possibly caused by the effects of floods. The vegetation patterns demonstrate that the area of Anxi County is a complete landscape unit. The range of the current nature reserve is not large enough for the purpose of conserving the unique biodiversity in this area.

  20. Impacts of Sloping Land Conversion Program on the vegetation in loess hilly and gully area of northern Shaanxi

    Ma Junfei; Lu Changhe; Yu Bohua

    2009-01-01

    Aiming at alleviating the serious soil erosion,the Chinese government initiated the Sloping Land Con.version Program (SLCP) in 1999.Now,after 8 years of project implementation,the ecological recovery effects of the SLCP have become the hot issue of academic circle.This paper,taking the loess hdl and gully area of northern Shaanxi as an example,presents a methodology for assessing the vegetation restoration effect of SLCP with normalized difference vegetation index (NDVI).The key components include calculation of the Growing Season NDVI (GSNDVI),and estimation of the NVDI change induced by climate and SLCP,re,wectively.Based on the method,the NDVI change between 2000 and 2006 was obtained using the GSNDVI that excluded the noise from snow and ice.Afier the part of total NDVI change caused by climate variation was estimated using empiric formulae,we obtained the part induced by human factors,i.e.the SLCP.The human induced part of NDVI change was considered as an approximation indicating the effect of the SLCP on the vegetation.Finally,we analyzed the NDVI change characters of the whole study area,different slope lands and different land use types by spatial statistics method Results show that the vegetation condition is significantly improved by the SLCP,particularly land types that directly involved in the SLCP,such as steeply slope farmlands,degraded grasslands,etc.

  1. Vegetation patterns and nature reserve construction in an extremely-arid desert in Anxi,NW China's Gansu Province

    2002-01-01

    Anxi County is located in the northwestern part of the Hexi Corridor in Gansu Province and has the sole national level nature reserve of extremely-arid desert in China.Phytosociological methods (Braun-Blanquet,1964) are used to classify plant community types in this area.Eleven are distinguished,including six of deserts,four of oases and one transitional type between deserts and oases.Direct gradient analysis ( DCA ) is employed to correlate the distribution of plant communities to physiogeographic conditions.This study makes clear that water is the most important ecological factor for the distribution of plant species and communities in this area.The effects of water have been demonstrated in different ways.A vegetation gradient from lower altitude to higher altitude in the southern part of the reserve is driven by a precipitation gradient.The effects of the depth of ground water table contribute to the differentiation of vegetation from desert to oasis in the flat area.In a finer scale,the washed gullies have obviously higher species richness and also higher vegetation cover than the surround gobi surfaces,possibly caused by the effects of floods.The vegetation patterns demonstrate that the area of Anxi County is a complete landscape unit.The range of the current nature reserve is not large enough for the purpose of conserving the unique biodiversity in this area.

  2. Remote sensing of aquatic vegetation: theory and applications.

    Silva, Thiago S F; Costa, Maycira P F; Melack, John M; Novo, Evlyn M L M

    2008-05-01

    Aquatic vegetation is an important component of wetland and coastal ecosystems, playing a key role in the ecological functions of these environments. Surveys of macrophyte communities are commonly hindered by logistic problems, and remote sensing represents a powerful alternative, allowing comprehensive assessment and monitoring. Also, many vegetation characteristics can be estimated from reflectance measurements, such as species composition, vegetation structure, biomass, and plant physiological parameters. However, proper use of these methods requires an understanding of the physical processes behind the interaction between electromagnetic radiation and vegetation, and remote sensing of aquatic plants have some particular difficulties that have to be properly addressed in order to obtain successful results. The present paper reviews the theoretical background and possible applications of remote sensing techniques to the study of aquatic vegetation.

  3. Selection of Hyperspectral Narrowbands (HNBs) and Composition of Hyperspectral Twoband Vegetation Indices (HVIs) for Biophysical Characterization and Discrimination of Crop Types Using Field Reflectance and Hyperion-EO-1 Data

    Thenkabail, Prasad S.; Mariotto, Isabella; Gumma, Murali Krishna; Middleton, Elizabeth M.; Landis, David R.; Huemmrich, K. Fred

    2013-01-01

    The overarching goal of this study was to establish optimal hyperspectral vegetation indices (HVIs) and hyperspectral narrowbands (HNBs) that best characterize, classify, model, and map the world's main agricultural crops. The primary objectives were: (1) crop biophysical modeling through HNBs and HVIs, (2) accuracy assessment of crop type discrimination using Wilks' Lambda through a discriminant model, and (3) meta-analysis to select optimal HNBs and HVIs for applications related to agriculture. The study was conducted using two Earth Observing One (EO-1) Hyperion scenes and other surface hyperspectral data for the eight leading worldwide crops (wheat, corn, rice, barley, soybeans, pulses, cotton, and alfalfa) that occupy approx. 70% of all cropland areas globally. This study integrated data collected from multiple study areas in various agroecosystems of Africa, the Middle East, Central Asia, and India. Data were collected for the eight crop types in six distinct growth stages. These included (a) field spectroradiometer measurements (350-2500 nm) sampled at 1-nm discrete bandwidths, and (b) field biophysical variables (e.g., biomass, leaf area index) acquired to correspond with spectroradiometer measurements. The eight crops were described and classified using approx. 20 HNBs. The accuracy of classifying these 8 crops using HNBs was around 95%, which was approx. 25% better than the multi-spectral results possible from Landsat-7's Enhanced Thematic Mapper+ or EO-1's Advanced Land Imager. Further, based on this research and meta-analysis involving over 100 papers, the study established 33 optimal HNBs and an equal number of specific two-band normalized difference HVIs to best model and study specific biophysical and biochemical quantities of major agricultural crops of the world. Redundant bands identified in this study will help overcome the Hughes Phenomenon (or "the curse of high dimensionality") in hyperspectral data for a particular application (e

  4. A preliminary study on vegetation-erosion dynamics and its applications

    WANG; Zhaoyin; WANG; Guangqian; LI; Changzhi

    2005-01-01

    Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the coupled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang watershed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

  5. [Treatment effect of biological filtration and vegetable floating-bed combined system on greenhouse turtle breeding wastewater].

    Chen, Chong-Jun; Zhang, Rui; Xiang, Kun; Wu, Wei-Xiang

    2014-08-01

    Unorganized discharge of greenhouse turtle breeding wastewater has brought several negative influences on the ecological environment in the rural area of Yangtze River Delta. Biological filtration and vegetable floating-bed combined system is a potential ecological method for greenhouse turtle breeding wastewater treatment. In order to explore the feasibility of this system and evaluate the contribution of vegetable uptake of nitrogen (N) and phosphorus (P) in treating greenhouse turtle breeding wastewater, three types of vegetables, including Ipomoea aquatica, lettuce and celery were selected in this study. Results showed the combined system had a high capacity in simultaneous removal of organic matter, N and P. The removal efficiencies of COD, NH4(+)-N, TN and TP from the wastewater reached up to 93.2%-95.6%, 97.2%-99.6%, 73.9%-93.1% and 74.9%-90.0%, respectively. System with I. aquatica had the highest efficiencies in N and P removal, followed by lettuce and celery. However, plant uptake was not the primary pathway for TN arid TP removal in the combined system. The vegetable uptake of N and P accounted for only 9.1%-25.0% of TN and TP removal from the wastewater while the effect of microorganisms would be dominant for N and P removal. In addition, the highest amounts of N and P uptake in I. aquatica were closely related with the biomass of plant. Results from the study indicated that the biological filtration and vegetable floating-bed combined system was an effective approach to treating greenhouse turtle breeding wastewater in China.

  6. Chemical ecology of the marine plankton.

    Roy, Jessie S; Poulson-Ellestad, Kelsey L; Drew Sieg, R; Poulin, Remington X; Kubanek, Julia

    2013-10-11

    This review summarizes recent work in the chemical ecology of pelagic marine ecosystems. In order to provide a comprehensive overview of advances in the field over the period covered, we have organized this review by ecological interaction type beginning with intraspecific interactions, then interspecific interactions (including mutualism, parasitism, competition, and predation), and finally community- and ecosystem-wide interactions.

  7. An evaluation of selected ecological benefits of forest stands under acid stress based on biogeochemical processes in a catchment in Southwestern China

    Zhang, J.

    2011-12-01

    Based on nutrient biogeochemical cycles between soil, plants and the atmosphere, four ecological functions and values of forest stands under acid stress in a small catchment in Southwestern China are evaluated in this work: nutrient retaining, carbon sequestration, erosion control and water conservation. Integrated remote sensing Landsat-5 TM spectral data and field measurements of acid deposition are applied to simulate the temporal and spatial distributions of soil acidification and nutrient cycling for a small catchment with various types of vegetations in Southwestern China, using the Model of Acidification of Groundwater in Catchments (MAGIC) coupled with a soil water balance module and a vegetation growth model. The major cations in the soil solution, the net primary productivity, the soil conservation and the rainfall intercept are considered in the evaluation of the four selected ecological benefits of forest stands in the study area. Biogeochemical processes including deposition, nitrification, weathering, mineralization, uptake, allocation and litterfall are considered in the simulation. The simulation results show that the average amounts of nutrient retaining, carbon sequestration, and soil and water conservation were 1.67 t/hm2, 2.96 t/hm2, 913 t/hm2 and 10000 t/hm2 respectively for the catchment during the period from April 2007 to April 2008. The ecological functions also vary with the vegetation types. The nutrient retaining amount is the highest in grassland and the mixed forest came next. The mixed forest has higher carbon sequestration amount than coniferous forest, shrubs and the grass. The coniferous forest and the shrubs have the highest soil conservation and water conservation amounts respectively. The forest ecological values for the selected four functions are also estimated by the prices of substitutes and found to be 20 times that of timber economic benefit. The forest ecological functions will change under different scenarios of acid

  8. Soil and vegetation surveillance

    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.

  9. Hyperspectral remote sensing of vegetation

    Thenkabail, Prasad S.; Lyon, John G.; Huete, Alfredo

    2011-01-01

    Hyperspectral narrow-band (or imaging spectroscopy) spectral data are fast emerging as practical solutions in modeling and mapping vegetation. Recent research has demonstrated the advances in and merit of hyperspectral data in a range of applications including quantifying agricultural crops, modeling forest canopy biochemical properties, detecting crop stress and disease, mapping leaf chlorophyll content as it influences crop production, identifying plants affected by contaminants such as arsenic, demonstrating sensitivity to plant nitrogen content, classifying vegetation species and type, characterizing wetlands, and mapping invasive species. The need for significant improvements in quantifying, modeling, and mapping plant chemical, physical, and water properties is more critical than ever before to reduce uncertainties in our understanding of the Earth and to better sustain it. There is also a need for a synthesis of the vast knowledge spread throughout the literature from more than 40 years of research.

  10. Post-fire vegetation recovery in Portugal based on spot/vegetation data

    Gouveia, C.; Dacamara, C. C.; Trigo, R. M.

    2010-04-01

    A procedure is presented that allows identifying large burned scars and the monitoring of vegetation recovery in the years following major fire episodes. The procedure relies on 10-day fields of Maximum Value Composites of Normalized Difference Vegetation Index (MVC-NDVI), with a 1 km×1 km spatial resolution obtained from the VEGETATION instrument. The identification of fire scars during the extremely severe 2003 fire season is performed based on cluster analysis of NDVI anomalies that persist during the vegetative cycle of the year following the fire event. Two regions containing very large burned scars were selected, located in Central and Southwestern Portugal, respectively, and time series of MVC-NDVI analysed before the fire events took place and throughout the post-fire period. It is shown that post-fire vegetation dynamics in the two selected regions may be characterised based on maps of recovery rates as estimated by fitting a monoparametric model of vegetation recovery to MVC-NDVI data over each burned scar. Results indicated that the recovery process in the region located in Central Portugal is mostly related to fire damage rather than to vegetation density before 2003, whereas the latter seems to have a more prominent role than vegetation conditions after the fire episode, e.g. in the case of the region in Southwestern Portugal. These differences are consistent with the respective predominant types of vegetation. The burned area located in Central Portugal is dominated by Pinus Pinaster whose natural regeneration crucially depends on the destruction of seeds present on the soil surface during the fire, whereas the burned scar in Southwestern Portugal was populated by Eucalyptus that may quickly re-sprout from buds after fire. Besides its simplicity, the monoparametric model of vegetation recovery has the advantage of being easily adapted to other low-resolution satellite data, as well as to other types of vegetation indices.

  11. Post-fire vegetation recovery in Portugal based ewline on spot/vegetation data

    C. Gouveia

    2010-04-01

    Full Text Available A procedure is presented that allows identifying large burned scars and the monitoring of vegetation recovery in the years following major fire episodes. The procedure relies on 10-day fields of Maximum Value Composites of Normalized Difference Vegetation Index (MVC-NDVI, with a 1 km×1 km spatial resolution obtained from the VEGETATION instrument. The identification of fire scars during the extremely severe 2003 fire season is performed based on cluster analysis of NDVI anomalies that persist during the vegetative cycle of the year following the fire event. Two regions containing very large burned scars were selected, located in Central and Southwestern Portugal, respectively, and time series of MVC-NDVI analysed before the fire events took place and throughout the post-fire period. It is shown that post-fire vegetation dynamics in the two selected regions may be characterised based on maps of recovery rates as estimated by fitting a monoparametric model of vegetation recovery to MVC-NDVI data over each burned scar. Results indicated that the recovery process in the region located in Central Portugal is mostly related to fire damage rather than to vegetation density before 2003, whereas the latter seems to have a more prominent role than vegetation conditions after the fire episode, e.g. in the case of the region in Southwestern Portugal. These differences are consistent with the respective predominant types of vegetation. The burned area located in Central Portugal is dominated by Pinus Pinaster whose natural regeneration crucially depends on the destruction of seeds present on the soil surface during the fire, whereas the burned scar in Southwestern Portugal was populated by Eucalyptus that may quickly re-sprout from buds after fire. Besides its simplicity, the monoparametric model of vegetation recovery has the advantage of being easily adapted to other low-resolution satellite data, as well as to other types of vegetation

  12. Wyoming big sagebrush associations of eastern Oregon; vegetation attributes

    This report provides a synopsis of several vegetative characteristics for the Wyoming big sagebrush complex in eastern Oregon covering the High Desert , Snake River, and Owyhee Ecological Provinces in Harney, Lake, and Malheur Counties. The complex has been grouped into six associations defined by t...

  13. Systemic allergic dermatitis caused by Apiaceae root vegetables

    Paulsen, Evy; Petersen, Thomas H; Fretté, Xavier C;

    2014-01-01

    Immediate hypersensitivity reactions to root vegetables of the Umbelliferae plant family (Apiaceae) is well known. Delayed-type hypersensitivity is rarely reported.......Immediate hypersensitivity reactions to root vegetables of the Umbelliferae plant family (Apiaceae) is well known. Delayed-type hypersensitivity is rarely reported....

  14. Nationwide classification of forest types of India using remote sensing and GIS.

    Reddy, C Sudhakar; Jha, C S; Diwakar, P G; Dadhwal, V K

    2015-12-01

    India, a mega-diverse country, possesses a wide range of climate and vegetation types along with a varied topography. The present study has cla