WorldWideScience

Sample records for semiarid northern great

  1. Amphibians of the northern Great Plains

    Science.gov (United States)

    Larson, Diane L.; Euliss, Ned H.; Lannoo, Michael J.; Mushet, David M.; Mac, M.J.; Opler, P.A.; Puckett Haecker, C. E.; Doran, P.D.

    1998-01-01

    No cry of alarm has been sounded over the fate of amphibian populations in the northern grasslands of North America, yet huge percentages of prairie wetland habitat have been lost, and the destruction continues. Scarcely 30% of the original mixedgrass prairie remains in Nebraska, South Dakota, and North Dakota (See Table 1 in this chapter). If amphibian populations haven’t declined, why haven’t they? Or, have we simply failed to notice? Amphibians in the northern grasslands evolved in a boom-or-bust environment: species that were unable to survive droughts lasting for years died out long before humans were around to count them. Species we find today are expert at seizing the rare, wet moment to rebuild their populations in preparation for the next dry season. When numbers can change so rapidly, who can say if a species is rare or common? A lot depends on when you look.

  2. Observing Semi-Arid Ecoclimates across Mountain Gradients in the Great Basin, USA

    Science.gov (United States)

    Strachan, Scotty

    Observation of climate and ecohydrological variables in mountain systems is a necessary (if challenging) endeavor for modern society. Water resources are often intimately tied to mountains, and high elevation environments are frequently home to unique landscapes and biota with limited geographical distributions. This is especially true in the temperate and semi-arid mountains of the western United States, and specifically the Great Basin. Stark contrasts in annual water balance and ecological populations are visible across steep elevational gradients in the region; and yet the bulk of our historical knowledge of climate and related processes comes from lowland observations. Interpolative models that strive to estimate conditions in mountains using existing datasets are often found to be inaccurate, making future projections of mountain climate and ecosystem response suspect. This study details the results of high-resolution topographically-diverse ecohydrological monitoring, and describes the character and seasonality of basic climatic variables such as temperature and precipitation as well as their impact on soil moisture and vegetation during the 2012-2015 drought sequence. Relationships of topography (elevation/aspect) to daily and seasonal temperatures are shown. Tests of the PRISM temperature model are performed at the large watershed scale, revealing magnitudes, modes, and potential sources of bias that could dramatically affect derivative scientific conclusions. A new method of precipitation phase partitioning to detect and quantify frozen precipitation on a sub-daily basis is described. Character of precipitation from sub-daily to annual scales is quantified across all major Great Basin vegetation/elevation zones, and the relationship of elevation to precipitation phase, intensity, and amount is explored. Water-stress responses of Great Basin conifers including Pinus flexilis, Pinus longaeva, and Pinus ponderosa are directly observed, showing potential

  3. Carbon storage capacity of semi-arid grassland soils and sequestration potentials in northern China.

    Science.gov (United States)

    Wiesmeier, Martin; Munro, Sam; Barthold, Frauke; Steffens, Markus; Schad, Peter; Kögel-Knabner, Ingrid

    2015-10-01

    Organic carbon (OC) sequestration in degraded semi-arid environments by improved soil management is assumed to contribute substantially to climate change mitigation. However, information about the soil organic carbon (SOC) sequestration potential in steppe soils and their current saturation status remains unknown. In this study, we estimated the OC storage capacity of semi-arid grassland soils on the basis of remote, natural steppe fragments in northern China. Based on the maximum OC saturation of silt and clay particles soils (grazing land, arable land, eroded areas) were estimated. The analysis of natural grassland soils revealed a strong linear regression between the proportion of the fine fraction and its OC content, confirming the importance of silt and clay particles for OC stabilization in steppe soils. This relationship was similar to derived regressions in temperate and tropical soils but on a lower level, probably due to a lower C input and different clay mineralogy. In relation to the estimated OC storage capacity, degraded steppe soils showed a high OC saturation of 78-85% despite massive SOC losses due to unsustainable land use. As a result, the potential of degraded grassland soils to sequester additional OC was generally low. This can be related to a relatively high contribution of labile SOC, which is preferentially lost in the course of soil degradation. Moreover, wind erosion leads to substantial loss of silt and clay particles and consequently results in a direct loss of the ability to stabilize additional OC. Our findings indicate that the SOC loss in semi-arid environments induced by intensive land use is largely irreversible. Observed SOC increases after improved land management mainly result in an accumulation of labile SOC prone to land use/climate changes and therefore cannot be regarded as contribution to long-term OC sequestration. © 2015 John Wiley & Sons Ltd.

  4. Long-term Agroecosystem Research in the Northern Great Plains.

    Science.gov (United States)

    Schmer, M.; Sanderson, M.; Liebig, M. A.; Wienhold, B.; Awada, T.; Papiernik, S.; Osborne, S.; Kemp, W.; Okalebo, J. A.; Riedall, W.

    2015-12-01

    The Northern Great Plains is the bread basket of the United States, accounting for a substantial portion of U.S. agricultural production. This region faces critical challenges regarding balancing food needs, resource conservation (e.g Ogallala aquifer), environmental concerns, and rural economy development. Developing transformative, multifunctional systems will require equally imaginative and efficient tools to help farmers manage complex agroecosystems in a rapidly changing climate. The Northern Plains long-term agroecosystem research (LTAR) site at Mandan, ND and the Platte River High Plains LTAR (ARS/University of Nebraska-Lincoln) at Lincoln, NE in collaboration with USDA-ARS research units in Brookings, SD and Fargo, ND are collaborating to address the grand challenge of providing and sustaining multiple service provisions from Northern Great Plains agroecosystems. We propose to attain these goals through sustainable intensification based on the adoption of conservation agriculture principles including reduced soil disturbance, livestock integration, and greater complexity and diversity in the cropping system. Here, we summarize new concepts these locations have pioneered in dynamic cropping systems, resource use efficiency, and agricultural management technologies. As part of the LTAR network, we will conduct long-term cross-site research to design and assess new agricultural practices and systems aimed at improving our understanding of decision making processes and outcomes across an array of agricultural systems.

  5. Oligocene paleogeography of the northern Great Plains and adjacent mountains

    International Nuclear Information System (INIS)

    Seeland, D.

    1985-01-01

    Early Oligocene paleogeography of the northern Great Plains and adjacent mountains is inferred in part from published surface and subsurface studies of the pre-Oligocene surface. These studies are combined with published and unpublished information on clast provenance, crossbedding orientation, and Eocene paleogeography. The Oligocene Arctic Ocean-Gulf of Mexico continental divide extended from the southern Absaroka Mountains east along the Owl Creek Mountains, across the southern Powder River Basin, through the northern Black Hills, and eastward across South Dakota. Streams north of the divide flowed northeastward. The Olligocene White River Group contains 50 to 90 percent airfall pyroclastic debris from a northern Great Basin source. Most of the uranium deposits of the region in pre-Oligocene rocks can be related to a uranium source in the volcanic ash of the White River; in many places the pre-Oligocene deposits can be related to specific Oligocene channels. Uranium deposits in sandstones of major Oligocene rivers are an important new type of deposit. The Oligocene channel sandstones also contain small quantities of gold, molybdenum, gas, and oil

  6. Saline lakes of the glaciated Northern Great Plains

    Science.gov (United States)

    Mushet, David M.

    2011-01-01

    Unless you have flown over the region or seen aerial photographs, it is hard to grasp the scale of the millions of lakes and wetlands that dot the prairie landscape of the glaciated Northern Great Plains (Figure 1). This region of abundant aquatic habitats within a grassland matrix provides for the needs of a wide diversity of wildlife species and has appropriately been deemed the "duck factory of North America." While the sheer number of lakes and wetlands within this area of the Northern Great Plains can be truly awe-inspiring, their diversity in terms of the chemical composition of their water adds an equally important component supporting biotic diversity and productivity. Water within these lakes and wetlands can range from extremely fresh with salinities approaching that of rainwater to hypersaline with salinity ten times greater than that of seawater. Additionally, while variation in salinity among these water bodies can be great, the ionic composition of lakes and wetlands with similar salinities can vary markedly, influencing the overall spatial and temporal diversity of the region's biota.

  7. Study on Rangeland production Potential and its Limitations in the Semi-Arid lands of Northern Kenya

    International Nuclear Information System (INIS)

    Keya, G.A.; Hornetz, B.

    1999-01-01

    Results obtained from recent studies focused on rangeland potential as influenced by human activity and climatic factors in the semi-arid and pastoral ecosystems of Northern Kenya indicated great temporal and spatial forage production variability. The objective of the studies was to document the primary production potential in relation to water stress (drought), herbivory and direct human activities. Efforts also focused on finding possibilities of increasing productivity while conserving the finite resources for sustainable use. Laboratory field and numeric methods were employed over several seasons and years. Forb and grass production was more viable than that of the brows (dwarf shrub) layer. Compared to forbs and dwarf shrubs, The grass layer contributed less to the total of production in all seasons, indicating that the region had less potential for grazers compared to browsers. Spatial-temporal variations in rangeland carrying capacity reflected the great spatial heterogeneity in vegetation types and production. Similarly, seasonal difference were very evident, with highest estimates in the long rainy and lowest during the dry and short rainy seasons, respectively. Factors limiting rangeland production potential and were identified to be moisture deficiency, resource-use conflicts, an increasing and partial sedentarised nomadic population, overgrazing, tree felling, and land degradation (desert encroachment). Measures that can increase rangelands production potential and provide a better way of life for the inhabitants of the region include: (a) identification of land degradation (e.g. by means of bio-indicators and Geographical Information systems, GIS); (b) technical interventions (i.e. soil and water conservation,restoration of degraded ares, fodder production); (c)socio-economic interventions (i.e. resolution of resource-use conflicts, alleviation of poverty, infrastructure development, improvement of livestock marketing channels, etc) and (d) continued

  8. Endemic shrubs in temperate arid and semiarid regions of northern China and their potentials for rangeland restoration.

    Science.gov (United States)

    Chu, Jianmin; Yang, Hongxiao; Lu, Qi; Zhang, Xiaoyan

    2015-06-03

    Some endemic shrubs in arid and semiarid ecosystems are in danger of extinction, and yet they can play useful roles in maintaining or restoring these ecosystems, thus practical efforts are needed to conserve them. The shrubs Amygdalus pedunculata Pall., Amygdalus mongolica (Maxim.) Ricker and Ammopiptanthus mongolicus (Maxim. ex Kom.) Cheng f. are endemic species in arid and semiarid regions of northern China, where rangeland desertification is pronounced due to chronic overgrazing. In this study, we tested the hypothesis that these endemic shrubs have developed adaptations to arid and semiarid environments and could play critical roles as nurse species to initiate the process of rangeland recovery. Based on careful vegetation surveys, we analysed the niches of these species in relation to precipitation, temperature and habitats. All sampling plots were categorized by these endemics and sorted by the non-metric multidimensional scaling method. Species ratios of each life form and species co-occurrence rates with the endemics were also evaluated. Annual average temperature and annual precipitation were found to be the key factors determining vegetation diversity and distributions. Amygdalus pedunculata prefers low hills and sandy land in temperate semiarid regions. Amygdalus mongolica prefers gravel deserts of temperate semiarid regions. Ammopiptanthus mongolicus prefers sandy land of temperate arid regions. Communities of A. pedunculata have the highest diversity and the largest ratios of long-lived grass species, whereas those of A. mongolicus have the lowest diversity but the largest ratios of shrub species. Communities of A. mongolica are a transition between the first two community types. These findings demonstrate that our focal endemic shrubs have evolved adaptations to arid and semiarid conditions, thus they can be nurse plants to stabilize sand ground for vegetation restoration. We suggest that land managers begin using these shrub species to restore

  9. Earliest Cucurbita from the Great Lakes, Northern USA

    Science.gov (United States)

    Monaghan, G. William; Lovis, William A.; Egan-Bruhy, Kathryn C.

    2006-03-01

    Directly dated Cucurbita from archaeological sites near Lake Huron expand the range and human usage of adventive, cultivated wild gourds or squash into the Great Lakes region, USA, by 4000 14C yr BP. The data also show that domesticated C. pepo squash was cultivated there by 3000 14C yr BP. Although milder Hypsithermal climate may have been a contributing factor, squash and gourds expanded northward during the mid-Holocene mainly by human agency and may be the first human-introduced adventive plant in temperate North America. Even after 3000 14C yr BP, when domesticated squash generally replaced wild varieties at northern sites, squash stands were probably informally managed rather than intensively cultivated.

  10. Quantifying uncertainties of seismic Bayesian inversion of Northern Great Plains

    Science.gov (United States)

    Gao, C.; Lekic, V.

    2017-12-01

    Elastic waves excited by earthquakes are the fundamental observations of the seismological studies. Seismologists measure information such as travel time, amplitude, and polarization to infer the properties of earthquake source, seismic wave propagation, and subsurface structure. Across numerous applications, seismic imaging has been able to take advantage of complimentary seismic observables to constrain profiles and lateral variations of Earth's elastic properties. Moreover, seismic imaging plays a unique role in multidisciplinary studies of geoscience by providing direct constraints on the unreachable interior of the Earth. Accurate quantification of uncertainties of inferences made from seismic observations is of paramount importance for interpreting seismic images and testing geological hypotheses. However, such quantification remains challenging and subjective due to the non-linearity and non-uniqueness of geophysical inverse problem. In this project, we apply a reverse jump Markov chain Monte Carlo (rjMcMC) algorithm for a transdimensional Bayesian inversion of continental lithosphere structure. Such inversion allows us to quantify the uncertainties of inversion results by inverting for an ensemble solution. It also yields an adaptive parameterization that enables simultaneous inversion of different elastic properties without imposing strong prior information on the relationship between them. We present retrieved profiles of shear velocity (Vs) and radial anisotropy in Northern Great Plains using measurements from USArray stations. We use both seismic surface wave dispersion and receiver function data due to their complementary constraints of lithosphere structure. Furthermore, we analyze the uncertainties of both individual and joint inversion of those two data types to quantify the benefit of doing joint inversion. As an application, we infer the variation of Moho depths and crustal layering across the northern Great Plains.

  11. Crop Sequence Influences on Sustainable Spring Wheat Production in the Northern Great Plains

    Directory of Open Access Journals (Sweden)

    Joseph M. Krupinsky

    2010-11-01

    Full Text Available Cropping systems in American agriculture are highly successful since World War II, but have become highly specialized, standardized, and simplified to meet the demands of an industrialized food system. Minimal attention has been given to the efficient exploitation of crop diversity and the synergistic and/or antagonistic relationships of crops in crop sequences. Objectives of our research were to determine if previous crop sequences have long-term benefits and/or drawbacks on spring wheat seed yield, seed N concentration, and seed precipitation-use efficiency in the semiarid northern Great Plains, USA. Research was conducted 6 km southwest of Mandan, ND using a 10 × 10 crop matrix technique as a research tool to evaluate multiple crop sequence effects on spring wheat (triticum aestivum L. production in 2004 and 2005. Spring wheat production risks can be mitigated when second year crop residue was dry pea (Pisium sativum L. averaged over all first year crop residues. When compared to spring wheat as second year crop residue in the dry year of 2004, dry pea as the second year residue crop resulted in a 30% spring wheat seed yield increase. Sustainable cropping systems need to use precipitation efficiently for crop production, especially during below average precipitation years like 2004. Precipitation use efficiency average over all treatments, during the below average precipitation year was 23% greater than the above average precipitation year of 2005. Diversifying crops in cropping systems improves production efficiencies and resilience of agricultural systems.

  12. Decreased runoff response to precipitation, Little Missouri River Basin, northern Great Plains, USA

    Science.gov (United States)

    Griffin, Eleanor R.; Friedman, Jonathan M.

    2017-01-01

    High variability in precipitation and streamflow in the semiarid northern Great Plains causes large uncertainty in water availability. This uncertainty is compounded by potential effects of future climate change. We examined historical variability in annual and growing season precipitation, temperature, and streamflow within the Little Missouri River Basin and identified differences in the runoff response to precipitation for the period 1976-2012 compared to 1939-1975 (n = 37 years in both cases). Computed mean values for the second half of the record showed little change (precipitation, but average annual runoff at the basin outlet decreased by 22%, with 66% of the reduction in flow occurring during the growing season. Our results show a statistically significant (p runoff response to precipitation (runoff ratio). Surface-water withdrawals for various uses appear to account for 1°C increases in January through March, are the dominant driver of the observed decrease in runoff response to precipitation in the Little Missouri River Basin.

  13. Retrieval of Aerosol Optical Depth in the Arid or Semiarid Region of Northern Xinjiang, China

    Directory of Open Access Journals (Sweden)

    Xinpeng Tian

    2018-01-01

    Full Text Available Satellite remote sensing has been widely used to retrieve aerosol optical depth (AOD, which is an indicator of air quality as well as radiative forcing. The dark target (DT algorithm is applied to low reflectance areas, such as dense vegetation, and the deep blue (DB algorithm is adopted for bright-reflecting regions. However, both DT and DB algorithms ignore the effect of surface bidirectional reflectance. This paper provides a method for AOD retrieval in arid or semiarid areas, in which the key points are the accurate estimation of surface reflectance and reasonable assumptions of the aerosol model. To reduce the uncertainty in surface reflectance, a minimum land surface reflectance database at the spatial resolution of 500 m for each month was constructed based on the moderate-resolution imaging spectroradiometer (MODIS surface reflectance product. Furthermore, a bidirectional reflectance distribution function (BRDF correction model was adopted to compensate for the effect of surface reflectance anisotropy. The aerosol parameters, including AOD, single scattering albedo, asymmetric factor, Ångström exponent and complex refractive index, are determined based on the observation of two sunphotometers installed in northern Xinjiang from July to August 2014. The AOD retrieved from the MODIS images was validated with ground-based measurements and the Terra-MODIS aerosol product (MOD04. The 500 m AOD retrieved from the MODIS showed high consistency with ground-based AOD measurements, with an average correlation coefficient of ~0.928, root mean square error (RMSE of ~0.042, mean absolute error (MAE of ~0.032, and the percentage falling within the expected error (EE of the collocations is higher than that for the MOD04 DB product. The results demonstrate that the new AOD algorithm is more suitable to represent aerosol conditions over Xinjiang than the DB standard product.

  14. The energy programme in Great Britain and Northern Ireland

    International Nuclear Information System (INIS)

    Fells, I.

    1985-01-01

    Great Britain and Northern Ireland are for the time being, thanks to North Sea oil and gas, self-supporting in energy supply (coal 36%, oil 34%, gas 23%, nuclear 6%, hydraulic 1%) a situation which may continue for 2 or 3 decades. By AD2101 it is expected that nuclear generation, including the use of fast-breeder reactors, will supply 50% of electrical energy (currently 14%). The article discusses primary energy sources with tabulated statistics from Government information, and mentions the 2000MW link with France now under construction. Among alternative resources the more promising appear to be wind generation and a Severn barrage; the latter could provide 2000-4000MW. Water power has very small potential but pumped storage (Dinorwic 1700MW) is important. The prospects for wave energy are poor. Acid rain is seen as a growing problem. Various ideas for energy saving are discussed and the present policy of examining the future of energy consumption in terms of 'scenarios' is briefly described. All of these include an increase in the proportion of electrical energy in the total consumption. (C.J.O.G.)

  15. Northern Great Basin Seasonal Lakes: Vulnerability to Climate Change.

    Science.gov (United States)

    Russell, M.; Eitel, J.

    2017-12-01

    Seasonal alkaline lakes in southeast Oregon, northeast California, and northwest Nevada serve as important habitat for migrating birds utilizing the Pacific Flyway, as well as local plant and animal communities. Despite their ecological importance, and anecdotal suggestions that these lakes are becoming less reliable, little is known about the vulnerability of these lakes to climate change. Our research seeks to understand the vulnerability of Northern Great Basin seasonal lakes to climate change. For this, we will be using historical information from the European Space Agency's Global Surface Water Explorer and the University of Idaho's gridMET climate product, to build a model that allows estimating surface water extent and timing based on climate variables. We will then utilize downscaled future climate projections to model surface water extent and timing in the coming decades. In addition, an unmanned aerial system (UAS) will be utilized at a subset of dried basins to obtain precise 3D bathymetry and calculate water volume hypsographs, a critical factor in understanding the likelihood of water persistence and biogeochemical habitat suitability. These results will be incorporated into decision support tools that land managers can utilize in water conservation, wildlife management, and climate mitigation actions. Future research may pair these forecasts with animal movement data to examine fragmentation of migratory corridors and species-specific impacts.

  16. Drought effect on selection of conservation reserve program grasslands by white-tailed deer on the Northern Great Plains

    Science.gov (United States)

    Grovenburg, T.W.; Jacques, C.N.; Klaver, R.W.; Jenks, J.A.

    2011-01-01

    Limited information exists regarding summer resource selection of white-tailed deer (Odocoileus virginianus) in grassland regions of the Northern Great Plains. During summers 2005-2006, we analyzed habitat selection of adult female white-tailed deer in north-central South Dakota. We collected 1905 summer locations and used 21 and 30 home ranges during 2005 and 2006, respectively, to estimate habitat selection. Results indicated that selection occurred at the population (P rural development areas containing permanent water sources during extreme drought conditions during 2006. Deer likely selected for fields of CRP grasslands during early summer for cover and natural forages, such as clover (Trifolium sp.), prior to the period when agricultural crops become available. Drought conditions occurring in semiarid prairie grassland regions may reduce food and water availability and contribute to subsequent changes in deer habitat selection across the range of the species.

  17. Potential nitrogen critical loads for northern Great Plains grassland vegetation

    Science.gov (United States)

    Symstad, Amy J.; Smith, Anine T.; Newton, Wesley E.; Knapp, Alan K.

    2015-01-01

    The National Park Service is concerned that increasing atmospheric nitrogen deposition caused by fossil fuel combustion and agricultural activities could adversely affect the northern Great Plains (NGP) ecosystems in its trust. The critical load concept facilitates communication between scientists and policy makers or land managers by translating the complex effects of air pollution on ecosystems into concrete numbers that can be used to inform air quality targets. A critical load is the exposure level below which significant harmful effects on sensitive elements of the environment do not occur. A recent review of the literature suggested that the nitrogen critical load for Great Plains vegetation is 10-25 kg N/ha/yr. For comparison, current atmospheric nitrogen deposition in NGP National Park Service (NPS) units ranges from ~4 kg N/ha/yr in the west to ~13 kg N/ha/yr in the east. The suggested critical load, however, was derived from studies far outside of the NGP, and from experiments investigating nitrogen loads substantially higher than current atmospheric deposition in the region.Therefore, to better determine the nitrogen critical load for sensitive elements in NGP parks, we conducted a four-year field experiment in three northern Great Plains vegetation types at Badlands and Wind Cave National Parks. The vegetation types were chosen because of their importance in NGP parks, their expected sensitivity to nitrogen addition, and to span a range of natural fertility. In the experiment, we added nitrogen at rates ranging from below current atmospheric deposition (2.5 kg N/ha/yr) to far above those levels but commensurate with earlier experiments (100 kg N/ha/yr). We measured the response of a variety of vegetation and soil characteristics shown to be sensitive to nitrogen addition in other studies, including plant biomass production, plant tissue nitrogen concentration, plant species richness and composition, non-native species abundance, and soil inorganic

  18. Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America

    Science.gov (United States)

    The book “Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America” summarizes published research in soil science and agronomy from various field experiments conducted in the soil-climatic/agro-ecological regions of the Northern Great Plains of North America....

  19. Hydrological Response of Semi-arid Degraded Catchments in Tigray, Northern Ethiopia

    Science.gov (United States)

    Teka, Daniel; Van Wesemael, Bas; Vanacker, Veerle; Hallet, Vincent

    2013-04-01

    To address water scarcity in the arid and semi-arid part of developing countries, accurate estimation of surface runoff is an essential task. In semi-arid catchments runoff data are scarce and therefore runoff estimation using hydrological models becomes an alternative. This research was initiated in order to characterize runoff response of semi-arid catchments in Tigray, North Ethiopia to evaluate SCS-CN for various catchments. Ten sub-catchments were selected in different river basins and rainfall and runoff were measured with automatic hydro-monitoring equipments for 2-3 years. The Curve Number was estimated for each Hydrological Response Unit (HRU) in the sub-catchments and runoff was modeled using the SCS-CN method at λ = 0.05 and λ = 0.20. The result showed a significant difference between the two abstraction ratios (P =0.05, df = 1, n= 132) and reasonable good result was obtained for predicted runoff at λ = 0.05 (NSE = -0.69; PBIAS = 18.1%). When using the CN values from literature runoff was overestimated compared to the measured value (e= -11.53). This research showed the importance of using measured runoff data to characterize semi-arid catchments and accurately estimate the scarce water resource. Key words: Hydrological response, rainfall-runoff, degraded environments, semi-arid, Ethiopia, Tigray

  20. Soil salinity study in Northern Great Plains sodium affected soil

    Science.gov (United States)

    Kharel, Tulsi P.

    Climate and land-use changes when combined with the marine sediments that underlay portions of the Northern Great Plains have increased the salinization and sodification risks. The objectives of this dissertation were to compare three chemical amendments (calcium chloride, sulfuric acid and gypsum) remediation strategies on water permeability and sodium (Na) transport in undisturbed soil columns and to develop a remote sensing technique to characterize salinization in South Dakota soils. Forty-eight undisturbed soil columns (30 cm x 15 cm) collected from White Lake, Redfield, and Pierpont were used to assess the chemical remediation strategies. In this study the experimental design was a completely randomized design and each treatment was replicated four times. Following the application of chemical remediation strategies, 45.2 cm of water was leached through these columns. The leachate was separated into 120- ml increments and analyzed for Na and electrical conductivity (EC). Sulfuric acid increased Na leaching, whereas gypsum and CaCl2 increased water permeability. Our results further indicate that to maintain effective water permeability, ratio between soil EC and sodium absorption ratio (SAR) should be considered. In the second study, soil samples from 0-15 cm depth in 62 x 62 m grid spacing were taken from the South Dakota Pierpont (65 ha) and Redfield (17 ha) sites. Saturated paste EC was measured on each soil sample. At each sampling points reflectance and derived indices (Landsat 5, 7, 8 images), elevation, slope and aspect (LiDAR) were extracted. Regression models based on multiple linear regression, classification and regression tree, cubist, and random forest techniques were developed and their ability to predict soil EC were compared. Results showed that: 1) Random forest method was found to be the most effective method because of its ability to capture spatially correlated variation, 2) the short wave infrared (1.5 -2.29 mum) and near infrared (0

  1. Rainfall-interception-evaporation-runoff relationships in a semi-arid catchment, northern Limpopo basin, Zimbabwe

    NARCIS (Netherlands)

    Love, D.; Uhlenbrook, S.; Corzo Perez, G.; Twomlow, S.; Zaag, van der P.

    2010-01-01

    Characterizing the response of a catchment to rainfall, in terms of the production of runoff vs the interception, transpiration and evaporation of water, is the first important step in understanding water resource availability in a catchment. This is particularly important in small semi-arid

  2. Nitrous oxide emissions from a Northern Great Plains soil as influenced by nitrogen management and cropping systems.

    Science.gov (United States)

    Dusenbury, M P; Engel, R E; Miller, P R; Lemke, R L; Wallander, R

    2008-01-01

    Field measurements of N2O emissions from soils are limited for cropping systems in the semiarid northern Great Plains (NGP). The objectives were to develop N2O emission-time profiles for cropping systems in the semiarid NGP, define important periods of loss, determine the impact of best management practices on N2O losses, and estimate direct N fertilizer-induced emissions (FIE). No-till (NT) wheat (Triticum Aestivum L.)-fallow, wheat-wheat, and wheat-pea (Pisum sativum), and conventional till (CT) wheat-fallow, all with three N regimes (200 and 100 kg N ha(-1) available N, unfertilized control); plus a perennial grass-alfalfa (Medicago sativa L.) system were sampled over 2 yr using vented chambers. Cumulative 2-yr N2O emissions were modest in contrast to reports from more humid regions. Greatest N2O flux activity occurred following urea-N fertilization (10-wk) and during freeze-thaw cycles. Together these periods comprised up to 84% of the 2-yr total. Nitrification was probably the dominant process responsible for N2O emissions during the post-N fertilization period, while denitrification was more important during freeze-thaw cycles. Cumulative 2-yr N2O-N losses from fertilized regimes were greater for wheat-wheat (1.31 kg N ha(-1)) than wheat-fallow (CT and NT) (0.48 kg N ha(-1)), and wheat-pea (0.71 kg N ha(-1)) due to an additional N fertilization event. Cumulative losses from unfertilized cropping systems were not different from perennial grass-alfalfa (0.28 kg N ha(-1)). Tillage did not affect N2O losses for the wheat-fallow systems. Mean FIE level was equivalent to 0.26% of applied N, and considerably below the Intergovernmental Panel on Climate Change mean default value (1.25%).

  3. Seasonal weather-related decision making for cattle production in the Northern Great Plains

    Science.gov (United States)

    High inter-annual variability of seasonal weather patterns can greatly affect forage and therefore livestock production in the Northern Great Plains. This variability can make it difficult for ranchers to set yearly stocking rates, particularly in advance of the grazing season. To better understand ...

  4. Where does blue water go in the semi-arid area of northern China under changing environments?

    Directory of Open Access Journals (Sweden)

    L. Ren

    2014-09-01

    Full Text Available River flow regimes in the semi-arid region of northern China show a decreasing trend in terms of quantity. River runoff (i.e. blue water reduction within the Laohahe catchment, the source area of the Liaohe River basin, manifests the aridity that exists widely in northern China. According to the water balance equation, during the past half-century, observed streamflow records in the Laohahe catchment show that blue water was re-directed to green water flow (i.e. evapotranspiration over annual and decadal time scales, whereas precipitation did not vary much. Human activities and land-use/land-cover changes are the fundamental reasons for such runoff change. In the studied catchment, extensive land reclamation for agriculture, water withdrawal from streams, and abstraction from aquifers for irrigation are the direct and main causes leading to the decrease in observed blue water. These factors further demonstrate that a land-use decision is also a decision about water. Therefore, there is a need for an integrated modelling framework to intrinsically link climate, hydrological, and agricultural models with social and economic analyses.

  5. Hydrogeologic and Hydrochemical Studies in a Semi-arid Watershed in Northern Mexico

    Science.gov (United States)

    Kretzschmar, T.; Vazquez, R.; Hinojosa, A.

    2006-12-01

    Within the Baja California panhandle exist quite a significant number of valleys which hydrogeology conditions are of great importance for the communities of the region. The Guadalupe Valley for example, located 30 km Northeast of Ensenada, hosts an important wine industry which presents a mayor factor for agriculture and tourism in Baja California. The irrigation is carried out basically by groundwater extracted from quaternary sediments filling this post-Miocene depression. Besides the intensive usage of the water by the wine industry in the Guadalupe Valley, the local waterworks installed in 1985 a gallery of 10 wells extracting around 320 l/s or 30 % of the total water extraction in the valley to supply the city of Ensenada with drinking water. A total of more than 500 wells with a combined annual consumption of about 28 Mio m3 are at the moment active in the valley. In the arid portions of northern Mexico Mountain front recharge presents an important recharge source for the alluvial aquifers. Other important sources directly related to precipitation are direct infiltration, recharge by surface water runoff in the arroyos as well as by active fault systems. The principal recharge sources for the Guadalupe Valley aquifer are the Sierra Juárez and the Guadalupe River. To be able to address the state of equilibrium of aquifer, recharge estimates for the watershed were calculated determining the runoff/infiltration relationships obtained by curve number determinations combined with the interpretation of satellite images. These results were integrated into an evaluation and hydrologic modeling of the hydrologic data pointing towards differences of up to over 50 percent in the recharge estimation in comparison to earlier studies carried out in the area. Furthermore hydrochemical and isotopic studies were carried out to show the effects of the excessive ground water extraction on the water quality of the aquifer. The hydrochemical data indicate that intense use of

  6. A conceptual model to facilitate amphibian conservation in the northern Great Plains

    Science.gov (United States)

    Mushnet, David M.; Euliss, Ned H.; Stockwell, Craig A.

    2012-01-01

    As pressures on agricultural landscapes to meet worldwide resource needs increase, amphibian populations face numerous threats including habitat destruction, chemical contaminants, disease outbreaks, wetland sedimentation, and synergistic effects of these perturbations. To facilitate conservation planning, we developed a conceptual model depicting elements critical for amphibian conservation in the northern Great Plains. First, we linked upland, wetland, and landscape features to specific ecological attributes. Ecological attributes included adult survival; reproduction and survival to metamorphosis; and successful dispersal and recolonization. Second, we linked ecosystem drivers, ecosystem stressors, and ecological effects of the region to each ecological attribute. Lastly, we summarized information on these ecological attributes and the drivers, stressors, and effects that work in concert to influence the maintenance of viable and genetically diverse amphibian populations in the northern Great Plains. While our focus was on the northern Great Plains, our conceptual model can be tailored to other geographic regions and taxa.

  7. A new agro-climatic classification for crop suitability zoning in northern semi-arid Ethiopia

    NARCIS (Netherlands)

    Araya, A.; Keesstra, S.D.; Stroosnijder, L.

    2010-01-01

    The agro-climatic resources of Giba catchment in northern Ethiopia were assessed and characterized. The objectives were (i) to ascertain the suitability of the climate for growing teff (Eragrostis tef) and barley (Hordeum vulgare); (ii) to determine the onset and length of the growing period (LGP),

  8. Evaluation of evapotranspiration methods for model validation in a semi-arid watershed in northern China

    Directory of Open Access Journals (Sweden)

    K. Schneider

    2007-05-01

    Full Text Available This study evaluates the performance of four evapotranspiration methods (Priestley-Taylor, Penman-Monteith, Hargreaves and Makkink of differing complexity in a semi-arid environment in north China. The results are compared to observed water vapour fluxes derived from eddy flux measurements. The analysis became necessary after discharge simulations using an automatically calibrated version of the Soil and Water Assessment Tool (SWAT failed to reproduce runoff measurements. Although the study area receives most of the annual rainfall during the vegetation period, high temperatures can cause water scarcity. We investigate which evapotranspiration method is most suitable for this environment and whether the model performance of SWAT can be improved with the most adequate evapotranspiration method.

    The evapotranspiration models were tested in two consecutive years with different rainfall amounts. In general, the simple Hargreaves and Makkink equations outmatch the more complex Priestley-Taylor and Penman-Monteith methods, although their performance depended on water availability. Effects on the quality of SWAT runoff simulations, however, remained minor. Although evapotranspiration is an important process in the hydrology of this steppe environment, our analysis indicates that other driving factors still need to be identified to improve SWAT simulations.

  9. Natural regeneration of northern hardwoods in the northern Great Lakes Region.

    Science.gov (United States)

    Carl H. Tubbs

    1977-01-01

    Reviews silvical and silvicultural information about natural regeneration pertinent to forestry practices in Lake State northern hardwood types. Seed production; effects of light, moisture, temperature and competition on establishment and growth; and how damage affects mortality rates and form are covered. Clearcutting, selection, and shelterwood experiments are...

  10. Particulate matter concentrations for mono-slope beef cattle facilities in the Northern Great Plains

    Science.gov (United States)

    Confined cattle facilities are an increasingly common housing system in the Northern Great Plains region of the United States. Producers may maintain a deep-bedded manure pack (Pack), they may remove all bedding/manure material from the pens weekly (Scrape), or use a combination of management styles...

  11. Low-dose glyphosate does not control annual bromes in the northern Great Plains

    Science.gov (United States)

    Annual bromes (downy brome and Japanese brome) have been shown to decrease perennial grass forage production and alter ecosystem functions in northern Great Plains rangelands. Large-scale chemical control might be a method for increasing rangeland forage production if low application rates confer co...

  12. Small mammals in successional prairie woodlands of the northern Great Plains

    Science.gov (United States)

    Mark A. Rumble; John E. Gobeille

    2001-01-01

    Prairie woodlands comprise about 1 percent of the landscape in the northern Great Plains. However, prairie woodlands provide habitat for far more than 1 percent of the wildlife species that occur in the prairie region. With increasing pressures on natural resources, managers need methods for managing wildlife habitat and biodiversity that are based on ecological...

  13. Grasshopper responses to fire and postfire grazing in the northern Great Plains vary among species

    Science.gov (United States)

    Rangeland management practices such as burning and grazing management may affect grasshopper populations by impacting development, survival and reproduction. Experiments are lacking in the northern Great Plains examining the effects of fire and grazing intensity on grasshoppers. As part of a larger ...

  14. Responses of Crop Water Use Efficiency to Climate Change and Agronomic Measures in the Semiarid Area of Northern China.

    Directory of Open Access Journals (Sweden)

    Jingting Zhang

    Full Text Available It has long been concerned how crop water use efficiency (WUE responds to climate change. Most of existing researches have emphasized the impact of single climate factor but have paid less attention to the effect of developed agronomic measures on crop WUE. Based on the long-term field observations/experiments data, we investigated the changing responses of crop WUE to climate variables (temperature and precipitation and agronomic practices (fertilization and cropping patterns in the semi-arid area of northern China (SAC during two periods, 1983-1999 and 2000-2010 (drier and warmer. Our results suggest that crop WUE was an intrinsical system sensitive to climate change and agronomic measures. Crops tend to reach the maximum WUE (WUEmax in warm-dry environment while reach the stable minimum WUE (WUEmin in warm-wet environment, with a difference between WUEmax and WUEmin ranging from 29.0%-55.5%. Changes in temperature and precipitation in the past three decades jointly enhanced crop WUE by 8.1%-30.6%. Elevated fertilizer and rotation cropping would increase crop WUE by 5.6-11.0% and 19.5-92.9%, respectively. These results indicate crop has the resilience by adjusting WUE, which is not only able to respond to subsequent periods of favorable water balance but also to tolerate the drought stress, and reasonable agronomic practices could enhance this resilience. However, this capacity would break down under impact of climate changes and unconscionable agronomic practices (e.g. excessive N/P/K fertilizer or traditional continuous cropping. Based on the findings in this study, a conceptual crop WUE model is constructed to indicate the threshold of crop resilience, which could help the farmer develop appropriate strategies in adapting the adverse impacts of climate warming.

  15. Changes of AM fungal abundance along environmental gradients in the arid and semi-arid grasslands of northern China.

    Directory of Open Access Journals (Sweden)

    Yajun Hu

    Full Text Available Arbuscular mycorrhizal (AM fungi are ubiquitous symbionts of higher plants in terrestrial ecosystems, while the occurrence of the AM symbiosis is influenced by a complex set of abiotic and biotic factors. To reveal the regional distribution pattern of AM fungi as driven by multiple environmental factors, and to understand the ecological importance of AM fungi in natural ecosystems, we conducted a field investigation on AM fungal abundance along environmental gradients in the arid and semi-arid grasslands of northern China. In addition to plant parameters recorded in situ, soil samples were collected, and soil chemo-physical and biological parameters were measured in the lab. Statistical analyses were performed to reveal the relative contribution of climatic, edaphic and vegetation factors to AM fungal abundance, especially for extraradical hyphal length density (HLD in the soil. The results indicated that HLD were positively correlated with mean annual temperature (MAT, soil clay content and soil pH, but negatively correlated with both soil organic carbon (SOC and soil available N. The multiple regressions and structural equation model showed that MAT was the key positive contributor and soil fertility was the key negative contributor to HLD. Furthermore, both the intraradical AM colonization (IMC and relative abundance of AM fungi, which was quantified by real-time PCR assay, tended to decrease along the increasing SOC content. With regard to the obvious negative correlation between MAT and SOC in the research area, the positive correlation between MAT and HLD implied that AM fungi could potentially mitigate soil carbon losses especially in infertile soils under global warming. However, direct evidence from long-term experiments is still expected to support the AM fungal contribution to soil carbon pools.

  16. Responses of Crop Water Use Efficiency to Climate Change and Agronomic Measures in the Semiarid Area of Northern China.

    Science.gov (United States)

    Zhang, Jingting; Ren, Wei; An, Pingli; Pan, Zhihua; Wang, Liwei; Dong, Zhiqiang; He, Di; Yang, Jia; Pan, Shufen; Tian, Hanqin

    2015-01-01

    It has long been concerned how crop water use efficiency (WUE) responds to climate change. Most of existing researches have emphasized the impact of single climate factor but have paid less attention to the effect of developed agronomic measures on crop WUE. Based on the long-term field observations/experiments data, we investigated the changing responses of crop WUE to climate variables (temperature and precipitation) and agronomic practices (fertilization and cropping patterns) in the semi-arid area of northern China (SAC) during two periods, 1983-1999 and 2000-2010 (drier and warmer). Our results suggest that crop WUE was an intrinsical system sensitive to climate change and agronomic measures. Crops tend to reach the maximum WUE (WUEmax) in warm-dry environment while reach the stable minimum WUE (WUEmin) in warm-wet environment, with a difference between WUEmax and WUEmin ranging from 29.0%-55.5%. Changes in temperature and precipitation in the past three decades jointly enhanced crop WUE by 8.1%-30.6%. Elevated fertilizer and rotation cropping would increase crop WUE by 5.6-11.0% and 19.5-92.9%, respectively. These results indicate crop has the resilience by adjusting WUE, which is not only able to respond to subsequent periods of favorable water balance but also to tolerate the drought stress, and reasonable agronomic practices could enhance this resilience. However, this capacity would break down under impact of climate changes and unconscionable agronomic practices (e.g. excessive N/P/K fertilizer or traditional continuous cropping). Based on the findings in this study, a conceptual crop WUE model is constructed to indicate the threshold of crop resilience, which could help the farmer develop appropriate strategies in adapting the adverse impacts of climate warming.

  17. Boundary Condition Effects on Hillslope Form and Soil Development Along a Climatic Gradient From Semiarid to Hyperarid in Northern Chile

    Science.gov (United States)

    Owen, J. J.; Dietrich, W. E.; Nishiizumi, K.; Bellugi, D.; Amundson, R.

    2008-12-01

    Modeling the development of hillslopes using mass balance equations has generated many testable hypotheses related to morphology, process rates, and soil properties, however it is only relatively recently that techniques for constraining these models (such as cosmogenic radionuclides) have become commonplace. As such, many hypotheses related to the effects of boundary conditions or climate on process rates and soil properties have been left untested. We selected pairs of hillslopes along a precipitation gradient in northern Chile (24°-30° S) which were either bounded by actively eroding (bedrock-bedded) channels or by stable or aggradational landforms (pediments, colluvial aprons, valley bottoms). For each hillslope we measured soil properties, atmospheric deposition rates, and bedrock denudation rates. We observe significant changes in soil properties with climate: there is a shift from thick, weathered soils in the semiarid south, to the near absence of soil in the arid middle, to salt-rich soils in the hyperarid north. Coincident with these are dramatic changes in the types and rates of processes acting on the soils. We found relatively quick, biotically-driven soil formation and transport in the south, and very slow, salt-driven processes in the north. Additionally, we observe systematic differences between hillslopes of different boundary condition within the same climate zone, such as thicker soils, gentler slopes, and slower erosion rates on hillslopes with a non-eroding boundary versus an eroding boundary. These support general predictions based on hillslope soil mass balance equations and geomorphic transport laws. Using parameters derived from our field data, we attempt to use a mass balance model of hillslope development to explore the effect of changing boundary conditions and/or shifting climate.

  18. Extensive summer water pulses do not necessarily lead to canopy growth of Great Basin and northern Mojave Desert shrubs.

    Science.gov (United States)

    Snyder, K A; Donovan, L A; James, J J; Tiller, R L; Richards, J H

    2004-10-01

    Plant species and functionally related species groups from arid and semi-arid habitats vary in their capacity to take up summer precipitation, acquire nitrogen quickly after summer precipitation, and subsequently respond with ecophysiological changes (e.g. water and nitrogen relations, gas exchange). For species that respond ecophysiologically, the use of summer precipitation is generally assumed to affect long-term plant growth and thus alter competitive interactions that structure plant communities and determine potential responses to climate change. We assessed ecophysiological and growth responses to large short-term irrigation pulses over one to three growing seasons for several widespread Great Basin and northern Mojave Desert shrub species: Chrysothamnus nauseosus, Sarcobatus vermiculatus, Atriplex confertifolia, and A. parryi. We compared control and watered plants in nine case studies that encompassed adults of all four species, juveniles for three of the species, and two sites for two of the species. In every comparison, plants used summer water pulses to improve plant water status or increase rates of functioning as indicated by other ecophysiological characters. Species and life history stage responses of ecophysiological parameters (leaf N, delta15N, delta13C, gas exchange, sap flow) were consistent with several previous short-term studies. However, use of summer water pulses did not affect canopy growth in eight out of nine comparisons, despite the range of species, growth stages, and site conditions. Summer water pulses affected canopy growth only for C. nauseosus adults. The general lack of growth effects for these species might be due to close proximity of groundwater at these sites, co-limitation by nutrients, or inability to respond due to phenological canalization. An understanding of the connections between short-term ecophysiological responses and growth, for different habitats and species, is critical for determining the significance of

  19. Land Cover Change in Northern Botswana: The Influence of Climate, Fire, and Elephants on Semi-Arid Savanna Woodlands

    Directory of Open Access Journals (Sweden)

    John Tyler Fox

    2017-10-01

    (p = 0.009, adj. R2 = 0.50, with a 41% increase in average fire occurrence in years when rainfall exceeded long-term mean annual precipitation (MAP. Loss of woodland was significantly associated with fire in locations experiencing 15 or more ignitions during the period 2001–2013 (p = 0.024. Although elephant-mediated damage is often cited as a major cause of woodland degradation in northern Botswana, we observed little evidence of unsustainable pressure on woodlands from growing elephant populations. Our data indicate broad-scale LCC processes in semi-arid savannas in Southern Africa are strongly coupled to environmental and anthropogenic forcings. Increased seasonal variability is likely to have important effects on the distribution of savanna plant communities due to climate-fire feedbacks. Long-term monitoring of LCC in these ecosystems is essential to improving land use planning and management strategies that protect biodiversity, as well as traditional cultures and livelihoods under future climate change scenarios for Southern Africa.

  20. Using Land Surface Phenology to Detect Land Use Change in the Northern Great Plains

    Science.gov (United States)

    Nguyen, L. H.; Henebry, G. M.

    2017-12-01

    The Northern Great Plains of the US have been undergoing many types of land cover / land use change over the past two decades, including expansion of irrigation, conversion of grassland to cropland, biofuels production, urbanization, and fossil fuel mining. Much of the literature on these changes has relied on post-classification change detection based on a limited number of observations per year. Here we demonstrate an approach to characterize land dynamics through land surface phenology (LSP) by synergistic use of image time series at two scales. Our study areas include regions of interest (ROIs) across the Northern Great Plains located within Landsat path overlap zones to boost the number of valid observations (free of clouds or snow) each year. We first compute accumulated growing degree-days (AGDD) from MODIS 8-day composites of land surface temperature (MOD11A2 and MYD11A2). Using Landsat Collection 1 surface reflectance-derived vegetation indices (NDVI, EVI), we then fit at each pixel a downward convex quadratic model linking the vegetation index to each year's progression of AGDD. This quadratic equation exhibits linearity in a mathematical sense; thus, the fitted models can be linearly mixed and unmixed using a set of LSP endmembers (defined by the fitted parameter coefficients of the quadratic model) that represent "pure" land cover types with distinct seasonal patterns found within the region, such as winter wheat, spring wheat, maize, soybean, sunflower, hay/pasture/grassland, developed/built-up, among others. Information about land cover corresponding to each endmember are provided by the NLCD (National Land Cover Dataset) and CDL (Cropland Data Layer). We use linear unmixing to estimate the likely proportion of each LSP endmember within particular areas stratified by latitude. By tracking the proportions over the 2001-2011 period, we can quantify various types of land transitions in the Northern Great Plains.

  1. Water quality monitoring protocol for wadeable streams and rivers in the Northern Great Plains Network

    Science.gov (United States)

    Wilson, Marcia H.; Rowe, Barbara L.; Gitzen, Robert A.; Wilson, Stephen K.; Paintner-Green, Kara J.

    2014-01-01

    Preserving the national parks unimpaired for the enjoyment of future generations is a fundamental purpose of the National Park Service (NPS). To address growing concerns regarding the overall physical, chemical, and biological elements and processes of park ecosystems, the NPS implemented science-based management through “Vital Signs” monitoring in 270 national parks (NPS 2007). The Northern Great Plains Network (NGPN) is among the 32 National Park Service Networks participating in this monitoring effort. The NGPN will develop protocols over the next several years to determine the overall health or condition of resources within 13 parks located in Nebraska, North Dakota, South Dakota, and Wyoming.

  2. COMPARATIVE LEGISLATIVE ANALYSIS OF ACTIVE BRIBERY IN THE UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND

    Directory of Open Access Journals (Sweden)

    Mijo Galiot

    2015-01-01

    Full Text Available Confronting socially unacceptable activities, especially corruptive criminal acts, including bribing, makes an important issue of every regulated legal system. The crucial part of such policies are the criminal polices. In this paper, the author deals with the criminal legislation of the United Kingdom of Great Britain and Northern Ireland, related to the matters of active bribing as one of the basic forms of corruptive behaviour. While comparing the way the penal system is regulated in the said country, the author comments basic similarities and differences of the passive bribing legal regulation in the United Kingdom and the Republic of Croatia.

  3. Transfer of Telegraph Technology to China: The Role of The Great northern Telegraph Company 1870-1890

    DEFF Research Database (Denmark)

    Baark, Erik

    This report examines the historical events surrounding the introduction of telegraph technology in China by the Danish Great Northern Telegraph Company. It describes the influence of Great Northern on diplomatic relations between Denmark and China during the decades of the 1870s and 1880s......, and the contributions in terms of the establishment of telegraph schools and development of a Chinese telegraph code that this company made as part of the technology transfer process....

  4. Evaluation of herbacceous biomass crops in the northern Great Plains. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, D.W.; Norby, W.E.; Erickson, D.O.; Johnson, R.G. [North Dakota State Univ., Fargo, ND (United States)

    1994-08-01

    Herbaceous lignocellulose crops are a potential renewable feedstock for biochemical conversion systems second in size to wood products. Several herbaceous crops are utilized as forage crops in the northern Great Plains, but forage quality considerations usually dictates a early harvest. Biomass cropping does not have this constraint; therefore, little information was available on herbaceous crops utilized as energy crops prior to this project. Our primary objectives were to evaluate the biomass yield and select chemical components of several herbaceous crops for energy crops in the northern Great Plains, compare the economic feasibility of energy crops with common competing crops, and evaluate biomass cropping on summer fallow lands. Three good, two marginal, and one irrigated sites were used during 1988 to 1992 for the first component. At least six perennial and four annual biomass species were included at all sites. Three to four nitrogen (N) levels and a crop-recrop comparison (annuals only) were management intensities included. Biomass cropping on idled lands was performed on dryland at Carrington and evaluated the effects of removing leguminous biomass on fallowed lands. This report summarizes results from the 5-year project.

  5. Variability of water properties in late spring in the northern Great South Channel

    Science.gov (United States)

    Chen, Changsheng; Beardsley, Robert C.; Limeburner, Richard

    Regional CTDIADCP surveys made in the northern Great South Channel (GSC) in late spring of 1988 and 1989 show different patterns of surface salinity in the extent of the freshwater plume east of Cape Cod. In April 1988, the surface plume was just beginning to form along the outer coast of Cape Cod, while 6 weeks later in the season in 1989, the minimum salinity was about 1.5 less, and a large pool of water fresher than 31.6 had pushed eastward over much of the northern GSC region. The difference in the amount of freshening between these two years is due primarily to the 6-week difference in the seasonal cycle and increased river discharge in 1989. The offshore spreading of the low-salinity plume was driven by the deeper circulation and upwelling-favorable winds. The distribution of Maine Intermediate Water (MIW) also significantly differed between April 1988 and June 1989. In April 1988, the seasonal thermocline was just beginning to form, and the spatial structure of MIW was relatively uniform. In June 1989, a narrow core of temperature minimum water (with T min in a range of 3.2-4.4°C) was found along the western flank of the northern GSC between 40 m and 120 m. This colder and fresher water spread to mix with the interior MIW as the core flowed southward into the central GSC. Hydrographic data plus satellite sea-surface temperature images showed a relatively permanent continuous thermal front (with a 10-km cross-isobath variation) along the eastern flank of Nantucket Shoals, across the northern shallow region of the GSC and along the northwestern flank of Georges Bank, which separated the well-mixed water over the shallow region of the GSC from stratified water in the center of the northern GSC. Comparison of the location of this front with theoretical predictions by LODER and GREENBERG [(1986) Continental Shelf Research, 6, 397-414] suggests that enhanced tidal mixing due to the spring-neap cycle is important in determining the relative balance between

  6. Palynology, sedimentology and environmental significance of Holocene swamps at northern Kaitoke, Great Barrier Island, New Zealand

    International Nuclear Information System (INIS)

    Horrocks, M.; Ogden, J.; Nichol, S.L.; Alloway, B.V.; Sutton, D.G.

    2000-01-01

    Pollen and sediment analyses of two cores from coastal freshwater swamps at northern Kaitoke (Kaitoke Swamp and Police Station Swamp), Great Barrier Island, show that c. 7300 calibrated yr BP Kaitoke Swamp was an estuary with tidal flats. Avicennia, now absent from the swamp area, was present in the estuary. By c. 4500 yr BP fresh water conditions had developed at the Kaitoke Swamp site as marine influences decreased. Around the same time, fresh water swamp conditions commenced at the Police Station Swamp site on the surface of a low lying area of a Late Pleistocene dune. A sandy layer at Kaitoke may represent rapid infilling followed by a dry soil surface until c. 1000 yr BP. Conifer-hardwood forest on the hills surrounding the sites c. 7300-c. 1800 yr BP was dominated by Dacrydium and Metrosideros. During this period, environmental conditions were relatively stable, with little change in forest composition. Between 1800 yr and 800 yr BP Kaitoke Swamp was reflooded, and the Police Station Swamp extended as a shallow lake over the nearby dune flat. These new shallow swamps were invaded by swamp forest (mainly Dacrycaprus with some Laurelia). The presence of charcoal and Pteridium spores above the Kaharoa Tephra suggests that major Polynesian deforestation at northern Kaitoke began c. 600 calibrated yr BP. (author). 41 refs., 4 figs., 2 tabs

  7. Woody encroachment in northern Great Plains grasslands: Perceptions, actions, and needs

    Science.gov (United States)

    Symstad, Amy J.; Leis, Sherry A.

    2017-01-01

    The United States Northern Great Plains (NGP) has a high potential for landscape-scale conservation, but this grassland landscape is threatened by encroachment of woody species. We surveyed NGP land managers to identify patterns in, and illustrate a broad range of, individual managers' perceptions on (1) the threat of woody encroachment to grasslands they manage, and (2) what management practices they use that may influence woody encroachment in this region. In the 34 surveys returned, which came from predominantly public lands in the study area, 79% of responses reported moderate or substantial woody encroachment. Eastern redcedar (Juniperus virginiana) and Rocky Mountain juniper (Juniperus scopulorum) were the most problematic encroachers. Thirty-one survey respondents said that prescribed fire was used on the lands they manage, and 64% of these responses reported that controlling woody encroachment was a fire management objective. However, only 18% of survey respondents using prescribed fire were achieving their desired fire return interval. Most respondents reported using mechanical and/or chemical methods to control woody species. In contrast to evidence from the central and southern Great Plains, few survey respondents viewed grazing as affecting encroachment. Although the NGP public land managers we surveyed clearly recognize woody encroachment as a problem and are taking steps to address it, many feel that the rate of their management is not keeping pace with the rate of encroachment. Developing strategies for effective woody plant control in a variety of NGP management contexts requires filling ecological science gaps and overcoming societal barriers to using prescribed fire.

  8. Potential effects of anthropogenic greenhouse gases on avian habitats and populations in the northern Great Plains

    Science.gov (United States)

    Larson, Diane L.

    1994-01-01

    Biotic response to the buildup of greenhouse gases in Earth's atmosphere is considerably more complex than an adjustment to changing temperature and precipitation. The fertilization effect carbon dioxide has on some plants, the impact UVB radiation has on health and productivity of organisms, and the resulting changes in competitive balance and trophic structure must also be considered. The intent of this paper is to review direct and indirect effects of anthropogenic greenhouse gases on wildlife, and to explore possible effects on populations of birds and their habitats in the northern Great Plains.Many of the potential effects of increasing greenhouse gases, such as declining plant nutritional value, changes in timing of insect emergence, and fewer and saltier wetlands, foreshadow a decline in avian populations on the Great Plains. However, other possible effects such as increased drought resistance and water use efficiency of vegetation, longer growing seasons, and greater overall plant biomass promise at least some mitigation. Effects of multiple simultaneous perturbations such as can be expected under doubled carbon dioxide scenarios will require substantial basic research to clarify.

  9. Plant Community and Soil Environment Response to Summer Fire in the Northern Great Plains

    Science.gov (United States)

    Fire is a keystone process in many ecosystems, especially grasslands. However, documentation of plant community and soil environment responses to fire is limited for semiarid grasslands relative to that for mesic grasslands. Replicated summer fire research is lacking, but much needed because summe...

  10. Dynamics of Soil Erosion as Influenced by Watershed Management Practices: A Case Study of the Agula Watershed in the Semi-Arid Highlands of Northern Ethiopia.

    Science.gov (United States)

    Fenta, Ayele Almaw; Yasuda, Hiroshi; Shimizu, Katsuyuki; Haregeweyn, Nigussie; Negussie, Aklilu

    2016-11-01

    Since the past two decades, watershed management practices such as construction of stone bunds and establishment of exclosures have been widely implemented in the semi-arid highlands of northern Ethiopia to curb land degradation by soil erosion. This study assessed changes in soil erosion for the years 1990, 2000 and 2012 as a result of such watershed management practices in Agula watershed using the Revised Universal Soil Loss Equation. The Revised Universal Soil Loss Equation factors were computed in a geographic information system for 30 × 30 m raster layers using spatial data obtained from different sources. The results revealed significant reduction in soil loss rates by about 55 % from about 28 to 12 t ha -1 per year in 1990-2000 and an overall 64 % reduction from 28 to 10 t ha -1 per year in 1990-2012. This change in soil loss is attributed to improvement in surface cover and stone bund practices, which resulted in the decrease in mean C and P-factors, respectively, by about 19 % and 34 % in 1990-2000 and an overall decrease in C-factor by 29 % in 1990-2012. Considerable reductions in soil loss were observed from bare land (89 %), followed by cultivated land (56 %) and shrub land (49 %). Furthermore, the reduction in soil loss was more pronounced in steeper slopes where very steep slope and steep slope classes experienced over 70 % reduction. Validation of soil erosion estimations using field observed points showed an overall accuracy of 69 %, which is fairly satisfactory. This study demonstrated the potential of watershed management efforts to bring remarkable restoration of degraded semi-arid lands that could serve as a basis for sustainable planning of future developments of areas experiencing severe land degradation due to water erosion.

  11. A spatio-temporal evaluation of the WRF physical parameterisations for numerical rainfall simulation in semi-humid and semi-arid catchments of Northern China

    Science.gov (United States)

    Tian, Jiyang; Liu, Jia; Wang, Jianhua; Li, Chuanzhe; Yu, Fuliang; Chu, Zhigang

    2017-07-01

    Mesoscale Numerical Weather Prediction systems can provide rainfall products at high resolutions in space and time, playing an increasingly more important role in water management and flood forecasting. The Weather Research and Forecasting (WRF) model is one of the most popular mesoscale systems and has been extensively used in research and practice. However, for hydrologists, an unsolved question must be addressed before each model application in a different target area. That is, how are the most appropriate combinations of physical parameterisations from the vast WRF library selected to provide the best downscaled rainfall? In this study, the WRF model was applied with 12 designed parameterisation schemes with different combinations of physical parameterisations, including microphysics, radiation, planetary boundary layer (PBL), land-surface model (LSM) and cumulus parameterisations. The selected study areas are two semi-humid and semi-arid catchments located in the Daqinghe River basin, Northern China. The performance of WRF with different parameterisation schemes is tested for simulating eight typical 24-h storm events with different evenness in space and time. In addition to the cumulative rainfall amount, the spatial and temporal patterns of the simulated rainfall are evaluated based on a two-dimensional composed verification statistic. Among the 12 parameterisation schemes, Scheme 4 outperforms the other schemes with the best average performance in simulating rainfall totals and temporal patterns; in contrast, Scheme 6 is generally a good choice for simulations of spatial rainfall distributions. Regarding the individual parameterisations, Single-Moment 6 (WSM6), Yonsei University (YSU), Kain-Fritsch (KF) and Grell-Devenyi (GD) are better choices for microphysics, planetary boundary layers (PBL) and cumulus parameterisations, respectively, in the study area. These findings provide helpful information for WRF rainfall downscaling in semi-humid and semi-arid

  12. Land Surface Phenologies of the Northern Great Plains: Possible Futures Arising From Land and Climate Change

    Science.gov (United States)

    Henebry, G. M.; Wimberly, M. C.; Senay, G.; Wang, A.; Chang, J.; Wright, C. R.; Hansen, M. C.

    2008-12-01

    Land cover change across the Northern Great Plains of North America over the past three decades has been driven by changes in agricultural management (conservation tillage; irrigation), government incentives (Conservation Reserve Program; subsidies to grain-based ethanol), crop varieties (cold-hardy soybean), and market dynamics (increasing world demand). Climate change across the Northern Great Plains over the past three decades has been evident in trends toward earlier warmth in the spring and a longer frost-free season. Together these land and climate changes induce shifts in local and regional land surface phenologies (LSPs). Any significant shift in LSP may correspond to a significant shift in evapotranspiration, with consequences for regional hydrometeorology. We explored possible future scenarios involving land use and climate change in six steps. First, we defined the nominal draw areas of current and future biorefineries in North Dakota, South Dakota, Nebraska, Minnesota, and Iowa and masked those land cover types within the draw areas that were unlikely to change to agricultural use (open water, settlements, forests, etc.). Second, we estimated the proportion of corn and soybean remaining within the masked draw areas using MODIS-derived crop maps. Third, in each draw area, we modified LSPs to simulate crop changes for a control and two treatment scenarios. In the control, we used LSP profiles identified from MODIS Collection 5 NBAR data. In one treatment, we increased the proportion of tallgrass LSPs in the draw areas to represent widespread cultivation of a perennial cellulosic crop, like switchgrass. In a second treatment, we increased the proportion of corn LSPs in the draw areas to represent increased corn cultivation. Fourth, we characterized the seasonal progression of the thermal regime associated with the LSP profiles using MODIS Land Surface Temperature (LST) products. Fifth, we modeled the LSP profile as a quadratic function of accumulated

  13. Hydrology of area 59, northern Great Plains and Rocky Mountain coal provinces, Colorado and Wyoming

    Science.gov (United States)

    Gaggiani, Neville G.; Britton, Linda J.; Minges, Donald R.; Kilpatrick, F.A.; Parker, Randolph S.; Kircher, James E.

    1987-01-01

    Hydrologic information and analysis aid in decisions to lease federally owned coal and to prepare necessary Environmental Assessments and Impact Study reports. This need has become even more critical with the enactment of Public Law 95-87, the "Surface Mining Control and Reclamation Act of 1977." This act requires an appropriate regulatory agency to issue permits, based on the review of permit-application data to assess hydrologic impacts. This report, which partially fulfills this requirement, is one in a series of nationwide coal province reports that present information thematically, through the use of a brief text and accompanying maps, graphs, charts, or other illustrations for single hydrologic topics. The report broadly characterizes the hydrology of Area 59 in north-central Colorado and southeastern Wyoming.The report area, located within the South Platte River basin, covers a 16,000-square-mile area of diverse geology, topography, and climate. This diversity results in contrasting hydrologic characteristics.The South Platte River, the major stream in the area, and most of its tributaries originate in granitic mountains and flow into and through the sedimentary rocks of the Great Plains. Altitudes range from less than 5,000 feet to more than 14,000 feet above sea level. Precipitation in the mountains may exceed 40 inches annually, much of it during the winter, and produces deep snowpacks. Snowmelt during the spring and summer produces most streamflow. Transmountain diversion of water from the streams on the western slope of the mountains also adds to the streamflow. Precipitation in the plains is as little as 10 inches annually. Streams that originate in the plains are ephemeral.Streamflow quality is best in the mountains, where dissolved-solids concentrations are generally small. Concentrations increase in the plains as streams flow through sedimentary basins, and as urbanization and irrigation increase. The quality of some mountain streams is affected by

  14. Subtask 7.3 - The Socioeconomic Impact of Climate Shifts in the Northern Great Plains

    Energy Technology Data Exchange (ETDEWEB)

    Jaroslav Solc; Tera Buckley; Troy Simonsen

    2007-12-31

    The Energy & Environmental Research Center (EERC) evaluated the water demand response/vulnerability to climate change factors of regional economic sectors in the northern Great Plains. Regardless of the cause of climatic trends currently observed, the research focused on practical evaluation of climate change impact, using water availability as a primary factor controlling long-term regional economic sustainability. Project results suggest that the Upper Missouri, Red River, and Upper Mississippi Watersheds exhibit analogous response to climate change, i.e., extended drought influences water availability in the entire region. The modified trend suggests that the next period for which the Red River Basin can expect a high probability of below normal precipitation will occur before 2050. Agriculture is the most sensitive economic sector in the region; however, analyses confirmed relative adaptability to changing conditions. The price of agricultural commodities is not a good indicator of the economic impact of climate change because production and price do not correlate and are subject to frequent and irregular government intervention. Project results confirm that high water demand in the primary economic sectors makes the regional economy extremely vulnerable to climatic extremes, with a similar response over the entire region. Without conservation-based water management policies, long-term periods of drought will limit socioeconomic development in the region and may threaten even the sustainability of current conditions.

  15. Breaking sod or breaking even? Flax on the northern Great Plains and Prairies, 1889-1930.

    Science.gov (United States)

    MacFayden, Joshua D

    2009-01-01

    A new thirst for paint and color in cities made extensive flax production profitable in the northern Great Plains and Prairies and contributed to the cultivation of the most fragile grassland ecosystems. The production of flax seed for linseed oil became an early spin-off of the Prairie wheat economy but, unlike wheat, flax vanished from old land after one or two rotations and reappeared in districts with the most new breaking. Officials explained the migrant crop as preparing native grasslands for cultivation or exhausting soil in old land, but farmers brought flax to their new breaking for other reasons. Producers would only put flax on any land when a range of economic and environmental conditions were in place. It was never sown without promise of adequately high prices or in the absence of affordable seed and other inputs. When price allowed, it usually appeared on new breaking because it could be planted later and transported further without upsetting the balance of other activities and without farmers learning many new techniques. Scientists discovered that diseased soil drove flax off old land, not soil exhaustion. Circumventing the disease was possible but costly, and farmers simply replaced flax with the next most lucrative commodity.

  16. Wind and wildlife in the Northern Great Plains: identifying low-impact areas for wind development.

    Directory of Open Access Journals (Sweden)

    Joseph Fargione

    Full Text Available Wind energy offers the potential to reduce carbon emissions while increasing energy independence and bolstering economic development. However, wind energy has a larger land footprint per Gigawatt (GW than most other forms of energy production and has known and predicted adverse effects on wildlife. The Northern Great Plains (NGP is home both to some of the world's best wind resources and to remaining temperate grasslands, the most converted and least protected ecological system on the planet. Thus, appropriate siting and mitigation of wind development is particularly important in this region. Steering energy development to disturbed lands with low wildlife value rather than placing new developments within large and intact habitats would reduce impacts to wildlife. Goals for wind energy development in the NGP are roughly 30 GW of nameplate capacity by 2030. Our analyses demonstrate that there are large areas where wind development would likely have few additional impacts on wildlife. We estimate there are ∼1,056 GW of potential wind energy available across the NGP on areas likely to have low-impact for biodiversity, over 35 times development goals. New policies and approaches will be required to guide wind energy development to low-impact areas.

  17. Potential Agricultural Uses of Flue Gas Desulfurization Gypsum in the Northern Great Plains

    Energy Technology Data Exchange (ETDEWEB)

    DeSutter, T.M.; Cihacek, L.J. [North Dakota State University, Fargo, ND (United States). Department of Soil Science

    2009-07-15

    Flue gas desulfurization gypsum (FGDG) is a byproduct from the combustion of coal for electrical energy production. Currently, FGDG is being produced by 15 electrical generating stations in Alabama, Florida, Indiana, Iowa, Kentucky, Ohio, North Carolina, South Carolina, Tennessee, Texas, and Wisconsin. Much of this byproduct is used in the manufacturing of wallboard. The National Network for Use of FGDG in Agriculture was initiated to explore alternative uses of this byproduct. In the northern Great Plains (North Dakota, South Dakota, and Montana), FGDG has the potential to be used as a Ca or S fertilizer, as an acid soil ameliorant, and for reclaiming or mitigating sodium-affected soils. Greater than 1.4 million Mg of FGDG could initially be used in these states for these purposes. Flue gas desulfurization gypsum can be an agriculturally important resource for helping to increase the usefulness of problem soils and to increase crop and rangeland production. Conducting beneficial use audits would increase the public awareness of this product and help identify to coal combustion electrical generating stations the agriculturally beneficial outlets for this byproduct.

  18. The role of fire in managing for biological diversity on native rangelands of the Northern Great Plains

    Science.gov (United States)

    Carolyn Hull Sieg

    1997-01-01

    A strategy for using fire to manage for biological diversity on native rangelands in the Northern Great Plains incorporates an understanding of its past frequency, timing and intensity. Historically, lightning and humans were the major fire setters, and the role of fire varied both in space and time. A burning regime that includes fires at various intervals, seasons...

  19. The Gulf of Carpentaria heated Torres Strait and the Northern Great Barrier Reef during the 2016 mass coral bleaching event

    NARCIS (Netherlands)

    Wolanski, E.; Andutta, Fernando P.; Deleersnijder, E.L.C.; Li, Y.; Thomas, C.J.

    The 2015/16 ENSO event increased the temperature of waters surrounding northeast Australia to above 30 °C, with large patches of water reaching 32 °C, for over two months, which led to severe bleaching of corals of the Northern Great Barrier Reef (NGBR). This study provides evidence gained from

  20. Effects of the "great recession" on the forest products sector in the northern region of the United States

    Science.gov (United States)

    Christopher W. Woodall; William G. Luppold; Peter J. Ince; Ronald J. Piva; Kenneth E. Skog

    2012-01-01

    The forest industry within the northern region of the United States has demonstrated a notable decline in terms of employment, number of mills, wood consumption, and forest harvests since 2000--a downturn exacerbated by the "Great Recession" of 2007-2009. Longer term industrial decline (since 2000) has been evidenced by reductions in secondary product (e.g.,...

  1. Dynamic cropping systems: Holistic approach for dryland agricultural systems in the northern Great Plains of North America

    Science.gov (United States)

    Cropping systems over the past century have developed greater crop specialization, more effectively conserve our soil and water resources, and are more resilient. The purpose of this chapter is to discuss the evolution of cropping systems in the Northern Great Plains and provide an approach to crop...

  2. Vulnerability of grazing and confined livestock in the Northern Great Plains to projected mid- and late- 21st century climate

    Science.gov (United States)

    The Northern Great Plains (NGP) region – Montana, Wyoming, Colorado, North Dakota, South Dakota and Nebraska – is a largely rural area that provides important agricultural and ecological services, including biological diversity. The NGP is projected to experience rising atmospheric CO2, warming and ...

  3. Deficit irrigation and fertilization strategies to improve soil quality and alfalfa yield in arid and semi-arid areas of northern China.

    Science.gov (United States)

    Jia, Qianmin; Kamran, Muhammad; Ali, Shahzad; Sun, Lefeng; Zhang, Peng; Ren, Xiaolong; Jia, Zhikuan

    2018-01-01

    In the arid and semi-arid areas of northern China, overexploitation of fertilizers and extensive irrigation with brackish groundwater have led to soil degradation and large areas of farmland have been abandoned. In order to improve the soil quality of abandoned farmland and make reasonable use of brackish groundwater, we conducted field trials in 2013 and 2014. In our study, we used three fertilization modes (CF, chemical fertilizer; OM, organic manure and chemical fertilizer; NF, no fertilizer) and three deficit irrigation levels (I 0 : 0 mm; I 75 : 75 mm; I 150 : 150 mm). The results showed that the activities of soil urease, alkaline phosphatase, invertase, catalase, and dehydrogenase in the OM treatment were significantly improved compared with those in the CF and NF treatments under the three deficit irrigation levels. Compared with NF, the OM treatment significantly increased soil organic carbon (SOC), water-soluble carbon (WSC), total nitrogen, microbial biomass carbon and nitrogen (MBC and MBN), and soil respiration rate, and significantly decreased soil C:N and MBC:MBN ratios and the metabolic quotient, thus improving the soil quality of abandoned farmland. Furthermore, the OM treatment increased alfalfa plant height, leaf area index, leaf chlorophyll content, and biomass yield. Under the CF and OM fertilization modes, the activities of urease and catalase in I 150 were significantly higher than those in I 0 , whereas irrigating without fertilizer did not significantly increase the activity of these two enzymes. Regardless of fertilization, alkaline phosphatase activity increased with an increase in irrigation amount, whereas invertase activity decreased. The results showed that deficit irrigation with brackish groundwater under the OM treatment can improve soil quality. Over the two years of the study, maximum SOC, total nitrogen, WSC, MBC, and MBN were observed under the OM-I 150 treatment, and the alfalfa biomass yield of this treatment was also

  4. Deficit irrigation and fertilization strategies to improve soil quality and alfalfa yield in arid and semi-arid areas of northern China

    Directory of Open Access Journals (Sweden)

    Qianmin Jia

    2018-02-01

    Full Text Available Background In the arid and semi-arid areas of northern China, overexploitation of fertilizers and extensive irrigation with brackish groundwater have led to soil degradation and large areas of farmland have been abandoned. In order to improve the soil quality of abandoned farmland and make reasonable use of brackish groundwater, we conducted field trials in 2013 and 2014. Methods In our study, we used three fertilization modes (CF, chemical fertilizer; OM, organic manure and chemical fertilizer; NF, no fertilizer and three deficit irrigation levels (I0: 0 mm; I75: 75 mm; I150: 150 mm. Results The results showed that the activities of soil urease, alkaline phosphatase, invertase, catalase, and dehydrogenase in the OM treatment were significantly improved compared with those in the CF and NF treatments under the three deficit irrigation levels. Compared with NF, the OM treatment significantly increased soil organic carbon (SOC, water-soluble carbon (WSC, total nitrogen, microbial biomass carbon and nitrogen (MBC and MBN, and soil respiration rate, and significantly decreased soil C:N and MBC:MBN ratios and the metabolic quotient, thus improving the soil quality of abandoned farmland. Furthermore, the OM treatment increased alfalfa plant height, leaf area index, leaf chlorophyll content, and biomass yield. Under the CF and OM fertilization modes, the activities of urease and catalase in I150 were significantly higher than those in I0, whereas irrigating without fertilizer did not significantly increase the activity of these two enzymes. Regardless of fertilization, alkaline phosphatase activity increased with an increase in irrigation amount, whereas invertase activity decreased. Discussion The results showed that deficit irrigation with brackish groundwater under the OM treatment can improve soil quality. Over the two years of the study, maximum SOC, total nitrogen, WSC, MBC, and MBN were observed under the OM-I150 treatment, and the alfalfa

  5. EVALUATING SHORT-TERM CLIMATE VARIABILITY IN THE LATE HOLOCENE OF THE NORTHERN GREAT PLAINS

    Energy Technology Data Exchange (ETDEWEB)

    Joseph H. Hartman

    1999-09-01

    Great Plains, northern hemisphere, and elsewhere. Finally these data can be integrated into a history of climate change and predictive climate models. This is not a small undertaking. The goals of researchers and the methods used vary considerably. The primary task of this project was literature research to (1) evaluate existing methodologies used in geologic climate change studies and evidence for short-term cycles produced by these methodologies and (2) evaluate late Holocene climate patterns and their interpretations.

  6. Tillage and residue effects on rainfed wheat and corn production in the Semi-Arid Regions of Northern China

    NARCIS (Netherlands)

    Wang, X.B.; Hoogmoed, W.B.; Perdok, U.D.; Cai, D.X.

    2003-01-01

    Field studies on tillage and residue management for spring corn were conducted at two sites, in Tunliu (1987-1990), and Shouyang (1992-1995) counties of Shanxi province in the semihumid arid regions of northern China. This paper discusses the effects of different fall tillage (winter fallow tillage)

  7. Turbulent characteristics of a semiarid atmospheric surface layer from cup anemometers – effects of soil tillage treatment (Northern Spain

    Directory of Open Access Journals (Sweden)

    S. Yahaya

    2003-10-01

    Full Text Available This paper deals with the characteristics of turbulent flow over two agricultural plots with various tillage treatments in a fallow, semiarid area (Central Aragon, Spain. The main dynamic characteristics of the Atmospheric Surface Layer (ASL measured over the experimental site (friction velocity, roughness length, etc., and energy budget, have been presented previously (Frangi and Richard, 2000. The current study is based on experimental measurements performed with cup anemometers located in the vicinity of the ground at 5 different levels (from 0.25 to 4 m and sampled at 1 Hz. It reveals that the horizontal wind variance, the Eulerian integral scales, the frequency range of turbulence and the turbulent kinetic energy dissipation rate are affected by the surface roughness. In the vicinity of the ground surface, the horizontal wind variance logarithmically increases with height, directly in relation to the friction velocity and the roughness length scale. It was found that the time integral scale (and subsequently the length integral scale increased with the surface roughness and decreased with the anemometer height. These variations imply some shifts in the meteorological spectral gap and some variations of the spectral peak length scale. The turbulent energy dissipation rate, affected by the soil roughness, shows a z-less stratification behaviour under stable conditions. In addition to the characterization of the studied ASL, this paper intends to show which turbulence characteristics, and under what conditions, are accessible through the cup anemometer.Key words. Meteorology and atmospheric dynamics (climatology, turbulence, instruments and techniques

  8. Turbulent characteristics of a semiarid atmospheric surface layer from cup anemometers – effects of soil tillage treatment (Northern Spain

    Directory of Open Access Journals (Sweden)

    S. Yahaya

    Full Text Available This paper deals with the characteristics of turbulent flow over two agricultural plots with various tillage treatments in a fallow, semiarid area (Central Aragon, Spain. The main dynamic characteristics of the Atmospheric Surface Layer (ASL measured over the experimental site (friction velocity, roughness length, etc., and energy budget, have been presented previously (Frangi and Richard, 2000. The current study is based on experimental measurements performed with cup anemometers located in the vicinity of the ground at 5 different levels (from 0.25 to 4 m and sampled at 1 Hz. It reveals that the horizontal wind variance, the Eulerian integral scales, the frequency range of turbulence and the turbulent kinetic energy dissipation rate are affected by the surface roughness. In the vicinity of the ground surface, the horizontal wind variance logarithmically increases with height, directly in relation to the friction velocity and the roughness length scale. It was found that the time integral scale (and subsequently the length integral scale increased with the surface roughness and decreased with the anemometer height. These variations imply some shifts in the meteorological spectral gap and some variations of the spectral peak length scale. The turbulent energy dissipation rate, affected by the soil roughness, shows a z-less stratification behaviour under stable conditions. In addition to the characterization of the studied ASL, this paper intends to show which turbulence characteristics, and under what conditions, are accessible through the cup anemometer.

    Key words. Meteorology and atmospheric dynamics (climatology, turbulence, instruments and techniques

  9. Preserving prairies: Understanding temporal and spatial patterns of invasive annual bromes in the Northern Great Plains

    Science.gov (United States)

    Ashton, Isabel; Symstad, Amy J.; Davis, Christopher; Swanson, Daniel J.

    2016-01-01

    Two Eurasian invasive annual brome grasses, cheatgrass (Bromus tectorum) and Japanese brome (Bromus japonicus), are well known for their impact in steppe ecosystems of the western United States where these grasses have altered fire regimes, reduced native plant diversity and abundance, and degraded wildlife habitat. Annual bromes are also abundant in the grasslands of the Northern Great Plains (NGP), but their impact and ecology are not as well studied. It is unclear whether the lessons learned from the steppe will translate to the mixed-grass prairie where native plant species are adapted to frequent fires and grazing. Developing a successful annual brome management strategy for National Park Service units and other NGP grasslands requires better understanding of (1) the impact of annual bromes on grassland condition; (2) the dynamics of these species through space and time; and (3) the relative importance of environmental factors within and outside managers' control for these spatiotemporal dynamics. Here, we use vegetation monitoring data collected from 1998 to 2015 in 295 sites to relate spatiotemporal variability of annual brome grasses to grassland composition, weather, physical environmental characteristics, and ecological processes (grazing and fire). Concern about the impact of these species in NGP grasslands is warranted, as we found a decline in native species richness with increasing annual brome cover. Annual brome cover generally increased over the time of monitoring but also displayed a 3- to 5-yr cycle of reduction and resurgence. Relative cover of annual bromes in the monitored areas was best predicted by park unit, weather, extant plant community, slope grade, soil composition, and fire history. We found no evidence that grazing reduced annual brome cover, but this may be due to the relatively low grazing pressure in our study. By understanding the consequences and patterns of annual brome invasion, we will be better able to preserve and restore

  10. Work-related ill-health: Republic of Ireland, Northern Ireland, Great Britain 2005-2012.

    Science.gov (United States)

    Money, A; Carder, M; Noone, P; Bourke, J; Hayes, J; Turner, S; Agius, R

    2015-01-01

    Data on work-related ill-health (WRIH) in the Republic of Ireland is inconsistent. To compare the incidence of WRIH in the Republic of Ireland (ROI), Northern Ireland (NI) and Great Britain (GB) reported by clinical specialists in skin and respiratory medicine and by specialist occupational physicians (OPs). Analysis of data reported to three surveillance schemes in The Health and Occupation Research (THOR) network in ROI and corresponding UK schemes. Contact dermatitis was the most frequently reported skin disease in the three areas. Asthma was the most frequently-reported respiratory disease in the ROI, while asbestos-related cases predominate in GB and NI. Mental health disorders, followed by musculoskeletal disorders were reported most frequently by OPs. Annual average incidence rates for skin disease were 2 per 100000 employed (95% confidence interval [CI] 1.9-2.8) in the ROI and 7 per 100000 for GB (95% CI 4.8-9.4). Unadjusted incidence rates for respiratory disease were 1 (95% CI 0.3-1) and 8 (95% CI 6.1-10.7) per 100000 in the ROI and GB, respectively; adjusted for reporter non-response, these figures increased to 15 (95% CI 11.3-19.6) and 32 (95% CI 28.4-35.6) per 100000 respectively. This is the first paper to include THOR data on WRIH from the ROI, NI and GB. Consistent and dedicated data collection in the ROI via the THOR schemes is viable and important in the light of a deficit of occupational ill-health data. Sustained efforts to improve participation are underway. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Buteo Nesting Ecology: Evaluating Nesting of Swainson’s Hawks in the Northern Great Plains

    Science.gov (United States)

    Inselman, Will M.; Datta, Shubham; Jenks, Jonathan A.; Jensen, Kent C.; Grovenburg, Troy W.

    2015-01-01

    Swainson’s hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson’s hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson’s hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, S Dist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%–42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson’s hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson’s hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson’s hawks arriving to the breeding grounds. PMID:26327440

  12. Buteo Nesting Ecology: Evaluating Nesting of Swainson's Hawks in the Northern Great Plains.

    Science.gov (United States)

    Inselman, Will M; Datta, Shubham; Jenks, Jonathan A; Jensen, Kent C; Grovenburg, Troy W

    2015-01-01

    Swainson's hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson's hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson's hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, SDist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%-42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson's hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson's hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson's hawks arriving to the breeding grounds.

  13. Limited change in dune mobility in response to a large decrease in wind power in semi-arid northern China since the 1970s

    Science.gov (United States)

    Mason, J.A.; Swinehart, J.B.; Lu, H.; Miao, X.; Cha, P.; Zhou, Y.

    2008-01-01

    The climatic controls on dune mobility, especially the relative importance of wind strength, remain incompletely understood. This is a key research problem in semi-arid northern China, both for interpreting past dune activity as evidence of paleoclimate and for predicting future environmental change. Potential eolian sand transport, which is approximately proportional to wind power above the threshold for sand entrainment, has decreased across much of northern China since the 1970s. Over the same period, effective moisture (ratio of precipitation to potential evapotranspiration) has not changed significantly. This "natural experiment" provides insight on the relative importance of wind power as a control on dune mobility in three dunefields of northern China (Mu Us, Otindag, and Horqin), although poorly understood and potentially large effects of human land use complicate interpretation. Dune forms in these three regions are consistent with sand transport vectors inferred from weather station data, suggesting that wind directions have remained stable and the stations adequately represent winds that shaped the dunes. The predicted effect of weaker winds since the 1970s would be dune stabilization, with lower sand transport rates allowing vegetation cover to expand. Large portions of all three dunefields remained stabilized by vegetation in the 1970s despite high wind power. Since the 1970s, trends in remotely sensed vegetation greenness and change in mobile dune area inferred from sequential Landsat images do indicate widespread dune stabilization in the eastern Mu Us region. On the other hand, expansion of active dunes took place farther west in the Mu Us dunefield and especially in the central Otindag dunefield, with little overall change in two parts of the Horqin dunes. Better ground truth is needed to validate the remote sensing analyses, but results presented here place limits on the relative importance of wind strength as a control on dune mobility in the

  14. Distribution of uranium and radium isotopes in an aquifer of a semi-arid region (Manouba-Essijoumi, Northern Tunisia)

    International Nuclear Information System (INIS)

    Added, A.; Ben Mammou, A.; Fernex, F.; Rezzoug, S.; Bernat, M.

    2005-01-01

    Groundwaters from the Sebkhet Essijoumi drainage basin, situated in northern Tunisia, West of the city of Tunis, were sampled and analyzed for uranium and radium isotopes. Low 234 U/ 238 U activity ratios coupled with relatively high 228 Ra and 238 U concentrations were found in the Manouba plain phreatic aquifer, at the northern part of the basin, where remote sensing has indicated that this plain corresponds to the main humid zone of the area. Low 234 U/ 238 U ratios probably reflected short residence time for waters in the Manouba plain, and high ratios longer residence time in the south, where water reaching the phreatic aquifer seems to have previously circulated in rocks constituting the southern hills. Assuming that, in the Manouba plain aquifer, the groundwater flows downstream from the Oued Lill pass area to the South-West of the Sebkha, the difference in the 228 Ra/ 226 Ra activity ratio suggests that the residence time of water has been 2.8 years longer near the Sebkha than upstream

  15. Distribution of uranium and radium isotopes in an aquifer of a semi-arid region (Manouba-Essijoumi, Northern Tunisia).

    Science.gov (United States)

    Added, A; Ben Mammou, A; Fernex, F; Rezzoug, S; Bernat, M

    2005-01-01

    Groundwaters from the Sebkhet Essijoumi drainage basin, situated in northern Tunisia, West of the city of Tunis, were sampled and analyzed for uranium and radium isotopes. Low (234)U/(238)U activity ratios coupled with relatively high (228)Ra and (238)U concentrations were found in the Manouba plain phreatic aquifer, at the northern part of the basin, where remote sensing has indicated that this plain corresponds to the main humid zone of the area. Low (234)U/(238)U ratios probably reflected short residence time for waters in the Manouba plain, and high ratios longer residence time in the south, where water reaching the phreatic aquifer seems to have previously circulated in rocks constituting the southern hills. Assuming that, in the Manouba plain aquifer, the groundwater flows downstream from the Oued Lill pass area to the South-West of the Sebkha, the difference in the (228)Ra/(226)Ra activity ratio suggests that the residence time of water has been 2.8 years longer near the Sebkha than upstream.

  16. Empirical and model-based estimates of spatial and temporal variations in net primary productivity in semi-arid grasslands of Northern China.

    Directory of Open Access Journals (Sweden)

    Shengwei Zhang

    Full Text Available Spatiotemporal variations in net primary productivity (NPP reflect the dynamics of water and carbon in the biosphere, and are often closely related to temperature and precipitation. We used the ecosystem model known as the Carnegie-Ames-Stanford Approach (CASA to estimate NPP of semiarid grassland in northern China counties between 2001 and 2013. Model estimates were strongly linearly correlated with observed values from different counties (slope = 0.76 (p < 0.001, intercept = 34.7 (p < 0.01, R2 = 0.67, RMSE = 35 g C·m-2·year-1, bias = -0.11 g C·m-2·year-1. We also quantified inter-annual changes in NPP over the 13-year study period. NPP varied between 141 and 313 g C·m-2·year-1, with a mean of 240 g C·m-2·year-1. NPP increased from west to east each year, and mean precipitation in each county was significantly positively correlated with NPP-annually, and in summer and autumn. Mean precipitation was positively related to NPP in spring, but not significantly so. Annual and summer temperatures were mostly negatively correlated with NPP, but temperature was positively correlated with spring and autumn NPP. Spatial correlation and partial correlation analyses at the pixel scale confirmed precipitation is a major driver of NPP. Temperature was negatively correlated with NPP in 99% of the regions at the annual scale, but after removing the effect of precipitation, temperature was positively correlated with the NPP in 77% of the regions. Our data show that temperature effects on production depend heavily on recent precipitation. Results reported here have significant and far-reaching implications for natural resource management, given the enormous size of these grasslands and the numbers of people dependent on them.

  17. Northern Great Plains Network water quality monitoring design for tributaries to the Missouri National Recreational River

    Science.gov (United States)

    Rowe, Barbara L.; Wilson, Stephen K.; Yager, Lisa; Wilson, Marcia H.

    2013-01-01

    The National Park Service (NPS) organized more than 270 parks with important natural resources into 32 ecoregional networks to conduct Inventory and Monitoring (I&M) activities for assessment of natural resources within park units. The Missouri National Recreational River (NRR) is among the 13 parks in the NPS Northern Great Plain Network (NGPN). Park managers and NGPN staff identified surface water resources as a high priority vital sign to monitor in park units. The objectives for the Missouri NRR water quality sampling design are to (1) assess the current status and long-term trends of select water quality parameters; and (2) document trends in streamflow at high-priority stream systems. Due to the large size of the Missouri River main stem, the NGPN water quality design for the Missouri NRR focuses on wadeable tributaries within the park unit. To correlate with the NGPN water quality protocols, monitoring of the Missouri NRR consists of measurement of field core parameters including dissolved oxygen, pH, specific conductance, and temperature; and streamflow. The purpose of this document is to discuss factors examined for selection of water quality monitoring on segments of the Missouri River tributaries within the Missouri NRR.Awareness of the complex history of the Missouri NRR aids in the current understanding and direction for designing a monitoring plan. Historical and current monitoring data from agencies and entities were examined to assess potential NGPN monitoring sites. In addition, the U.S. Environmental Protection Agency 303(d) list was examined for the impaired segments on tributaries to the Missouri River main stem. Because major tributaries integrate water quality effects from complex combinations of land use and environmental settings within contributing areas, a 20-mile buffer of the Missouri NRR was used to establish environmental settings that may impact the water quality of tributaries that feed the Missouri River main stem. For selection of

  18. Hydrology of area 53, Northern Great Plains and Rocky Mountain coal provinces, Colorado, Wyoming, and Utah

    Science.gov (United States)

    Driver, N.E.; Norris, J.M.; Kuhn, Gerhard; ,

    1984-01-01

    Hydrologic information and analysis are needed to aid in decisions to lease Federally owned coal and for the preparation of the necessary Environmental Assessments and Impact Study Reports. This need has become even more critical with the enactment of the Surface Mining Control and Reclamation Act of 1977 (Public Law 95-87). This report, one in a series of nationwide coal province reports, presents information thematically by describing single hydrologic topics through the use of brief texts and accompanying maps, graphs, or other illustrations. The report broadly characterizes the hydrology of Area 53 in northwestern Colorado, south-central Wyoming, and northeastern Utah. The report area, located primarily in the Wyoming Basin and Colorado Plateau physiographic provinces, consists of 14,650 square miles of diverse geology, topography, and climate. This diversity results in contrasting hydrologic characteristics. The two major rivers, the Yampa and the White Rivers, originate in humid granitic and basaltic mountains, then flow over sedimentary rocks underlying semiarid basins to their respective confluences with the Green River. Altitudes range from 4,800 to greater than 12,000 feet above sea level. Annual precipitation in the mountains, as much as 60 inches, is generally in the form of snow. Snowmelt produces most streamflow. Precipitation in the lower altitude sedimentary basins, ranging from 8 to 16 inches, is generally insufficient to sustain streamflow; therefore, most streams originating in the basins (where most of the streams in coal-mining areas originate) are ephemeral. Streamflow quality is best in the mountains where dissolved-solids concentrations generally are small. As streams flow across the sedimentary basins, mineral dissolution from the sedimentary rocks and irrigation water with high mineral content increase the dissolved-solids concentrations in a downstream direction. Due to the semiarid climate of the basins, soils are not adequately leached

  19. Spatial variation in seed bank dynamics of two annual brome species in the northern Great Plains

    Science.gov (United States)

    Annual bromes decrease forage production in northern central plains rangelands of North America. Early life history stages are when plants are most failure-prone, yet studying death post-germination and prior to emergence is difficult. In seed bank collections conducted over the course of two growin...

  20. Cheatgrass percent cover change: Comparing recent estimates to climate change − Driven predictions in the Northern Great Basin

    Science.gov (United States)

    Boyte, Stephen P.; Wylie, Bruce K.; Major, Donald J.

    2016-01-01

    Cheatgrass (Bromus tectorum L.) is a highly invasive species in the Northern Great Basin that helps decrease fire return intervals. Fire fragments the shrub steppe and reduces its capacity to provide forage for livestock and wildlife and habitat critical to sagebrush obligates. Of particular interest is the greater sage grouse (Centrocercus urophasianus), an obligate whose populations have declined so severely due, in part, to increases in cheatgrass and fires that it was considered for inclusion as an endangered species. Remote sensing technologies and satellite archives help scientists monitor terrestrial vegetation globally, including cheatgrass in the Northern Great Basin. Along with geospatial analysis and advanced spatial modeling, these data and technologies can identify areas susceptible to increased cheatgrass cover and compare these with greater sage grouse priority areas for conservation (PAC). Future climate models forecast a warmer and wetter climate for the Northern Great Basin, which likely will force changing cheatgrass dynamics. Therefore, we examine potential climate-caused changes to cheatgrass. Our results indicate that future cheatgrass percent cover will remain stable over more than 80% of the study area when compared with recent estimates, and higher overall cheatgrass cover will occur with slightly more spatial variability. The land area projected to increase or decrease in cheatgrass cover equals 18% and 1%, respectively, making an increase in fire disturbances in greater sage grouse habitat likely. Relative susceptibility measures, created by integrating cheatgrass percent cover and temporal standard deviation datasets, show that potential increases in future cheatgrass cover match future projections. This discovery indicates that some greater sage grouse PACs for conservation could be at heightened risk of fire disturbance. Multiple factors will affect future cheatgrass cover including changes in precipitation timing and totals and

  1. Communication of 19 June 1997 received from the resident representative of the United Kingdom of Great Britain and Northern Ireland to the International Atomic Energy Agency

    International Nuclear Information System (INIS)

    1997-07-01

    The document reproduces the text of a letter dated 19 June 1997 received by the Director General of the IAEA from the Resident Representative of the United Kingdom of Great Britain and Northern Ireland, referring to the Revised Supplementary Agreement Concerning the Provision of Technical Assistance by the International Atomic Energy Agency to the Government of the United Kingdom of Great Britain and Northern Ireland on behalf of the Government of Hong Kong done at Vienna on 4 February 1983

  2. The CO2 exchange of biological soil crusts in a semiarid grass-shrubland at the northern transition zone of the Negev desert, Israel

    Directory of Open Access Journals (Sweden)

    M. O. Andreae

    2008-10-01

    Full Text Available Biological soil crusts (BSC contribute significantly to the soil surface cover in many dryland ecosystems. A mixed type of BSC, which consists of cyanobacteria, mosses and cyanolichens, constitutes more than 60% of ground cover in the semiarid grass-shrub steppe at Sayeret Shaked in the northern Negev Desert, Israel. This study aimed at parameterizing the carbon sink capacity of well-developed BSC in undisturbed steppe systems. Mobile enclosures on permanent soil borne collars were used to investigate BSC-related CO2 fluxes in situ and with natural moisture supply during 10 two-day field campaigns within seven months from fall 2001 to summer 2002. Highest BSC-related CO2 deposition between –11.31 and –17.56 mmol m−2 per 15 h was found with BSC activated from rain and dew during the peak of the winter rain season. Net CO2 deposition by BSC was calculated to compensate 120%, –26%, and less than 3% of the concurrent soil CO2 efflux from November–January, February–May and November–May, respectively. Thus, BSC effectively compensated soil CO2 effluxes when CO2 uptake by vascular vegetation was probably at its low point. Nighttime respiratory emission reduced daily BSC-related CO2 deposition within the period November–January by 11–123% and on average by 27%. The analysis of CO2 fluxes and water inputs from the various sources showed that the bulk of BSC-related CO2 deposition occurs during periods with frequent rain events and subsequent condensation from water accumulated in the upper soil layers. Significant BSC activity on days without detectable atmospheric water supply emphasized the importance of high soil moisture contents as additional water source for soil-dwelling BSC, whereas activity upon dew formation at low soil water contents was not of major importance for BSC-related CO2 deposition. However, dew may still be important in attaining a pre-activated status during the transition from a long "summer" anabiosis towards

  3. Dendroclimatic potential of plains cottonwood (Populus deltoides subsp. monilifera) from the Northern Great Plains, USA

    Science.gov (United States)

    Edmonson, Jesse; Friedman, Jonathan; Meko, David; Touchan, Ramzi; Scott, Julian; Edmonson, Alan

    2014-01-01

    A new 368-year tree-ring chronology (A.D. 1643–2010) has been developed in western North Dakota using plains cottonwood (Populus deltoides subsp. monilifera) growing on the relatively undisturbed floodplain of the Little Missouri River in the North Unit of Theodore Roosevelt National Park. We document many slow-growing living trees between 150–370 years old that contradict the common understanding that cottonwoods grow fast and die young. In this northern location, cottonwood produces distinct annual rings with dramatic interannual variability that strongly crossdate. The detrended tree-ring chronology is significantly positively correlated with local growing season precipitation and soil moisture conditions (r  =  0.69). This time series shows periods of prolonged low radial tree growth during the known droughts of the instrumental record (e.g. 1931–1939 and 1980–1981) and also during prehistory (e.g. 1816–1823 and 1856–1865) when other paleoclimate studies have documented droughts in this region. Tree rings of cottonwood will be a useful tool to help reconstruct climate, streamflow, and the floodplain history of the Little Missouri River and other northern river systems.

  4. The Gulf of Carpentaria heated Torres Strait and the Northern Great Barrier Reef during the 2016 mass coral bleaching event

    Science.gov (United States)

    Wolanski, E.; Andutta, F.; Deleersnijder, E.; Li, Y.; Thomas, C. J.

    2017-07-01

    The 2015/16 ENSO event increased the temperature of waters surrounding northeast Australia to above 30 °C, with large patches of water reaching 32 °C, for over two months, which led to severe bleaching of corals of the Northern Great Barrier Reef (NGBR). This study provides evidence gained from remote-sensing data, oceanographic data and oceanographic modeling, that three factors caused this excessive heating, namely: 1) the shutdown of the North Queensland Coastal Current, which would otherwise have flushed and cooled the Northern Coral Sea and the NGBR through tidal mixing 2) the advection of warm (>30 °C) water from the Gulf of Carpentaria eastward through Torres Strait and then southward over the NGBR continental shelf, and 3) presumably local solar heating. The eastward flux of this warm water through Torres Strait was driven by a mean sea level difference on either side of the strait that in turn was controlled by the wind, which also generated the southward advection of this warm water onto the NGBR shelf. On the NGBR shelf, the residence time of this warm water was longer inshore than offshore, and this may explain the observed cross-shelf gradient of coral bleaching intensity. The fate of the Great Barrier Reef is thus controlled by the oceanography of surrounding seas.

  5. Disruption of Saturn's quasi-periodic equatorial oscillation by the great northern storm

    Science.gov (United States)

    Fletcher, Leigh N.; Guerlet, Sandrine; Orton, Glenn S.; Cosentino, Richard G.; Fouchet, Thierry; Irwin, Patrick G. J.; Li, Liming; Flasar, F. Michael; Gorius, Nicolas; Morales-Juberías, Raúl

    2017-11-01

    The equatorial middle atmospheres of the Earth1, Jupiter2 and Saturn3,4 all exhibit a remarkably similar phenomenon—a vertical, cyclic pattern of alternating temperatures and zonal (east-west) wind regimes that propagate slowly downwards with a well-defined multi-year period. Earth's quasi-biennial oscillation (QBO) (observed in the lower stratospheric winds with an average period of 28 months) is one of the most regular, repeatable cycles exhibited by our climate system1,5,6, and yet recent work has shown that this regularity can be disrupted by events occurring far away from the equatorial region, an example of a phenomenon known as atmospheric teleconnection7,8. Here, we reveal that Saturn's equatorial quasi-periodic oscillation (QPO) (with an 15-year period3,9) can also be dramatically perturbed. An intense springtime storm erupted at Saturn's northern mid-latitudes in December 201010-12, spawning a gigantic hot vortex in the stratosphere at 40° N that persisted for three years13. Far from the storm, the Cassini temperature measurements showed a dramatic 10 K cooling in the 0.5-5 mbar range across the entire equatorial region, disrupting the regular QPO pattern and significantly altering the middle-atmospheric wind structure, suggesting an injection of westward momentum into the equatorial wind system from waves generated by the northern storm. Hence, as on Earth, meteorological activity at mid-latitudes can have a profound effect on the regular atmospheric cycles in Saturn's tropics, demonstrating that waves can provide horizontal teleconnections between the phenomena shaping the middle atmospheres of giant planets.

  6. Some Features of the Functioning of the Northern Branch of the Great Silk Road

    Directory of Open Access Journals (Sweden)

    Anatoliy S. Skripkin

    2017-06-01

    Full Text Available The fact of existing economic relations in the north branch of The Great silk route is usually restored according to Claudius Ptolemey. There are some evidences to connect their activation with the establishment of political domination of Alans in the South-East of Europe. The analysis of archaeological material gives the information that not all findings of Chinese artifacts in Sarmatian burial complexes of the first century AD are the result of trade links and most of them have been brought here in the result of nomads’ migrations. The appearance of the Alans in the steppes of South-Eastern Europe refers to the first century AD. This tribal association was formed in Central Asia. Alans subdue the vast steppes from the Aral sea to the Don. In the early historical stage the Lower Don becomes their political center. In burials belonging to the Alanian nobility, a large number of items of Eastern origin were discovered. A great number of them were brought here upon the arrival of the new nomads. Economic relations in this area begin to improve after the establishment of political stability, which was reflected in the composition of Claudius Ptolemy.

  7. The importance of Northern Dobrogea in the migration of Great Cormorant (Phalacrocorax carbo

    Directory of Open Access Journals (Sweden)

    SÁNDOR D. Attila

    2009-09-01

    Full Text Available The Great Cormorants breeding and migrating through Dobrogea belong to the Phalacrocorax carbo sinensis subspecies. It is the subspecies with the most migratory populations out of the 12 subspecies ofGreat Cormorant. The species is in expansion in most regions of Europe, the P. c. sinensis subspecies’ range is expanding the most. In Romania both the number of colonies and their size have increased since 1990. The observed increase was too fast to be based only on the reproduction rate of the original local population. We suspect that a certain degree of the increase is fuelled by cormorants originating from other populations. Out of 667 cormorants ringedduring their nesting period in the Danube Delta 11 (1.64 % were recovered, while there are 15 recoveries of this speciesringed in other countries and recaptured in Dobrogea. Most of the birds ringed in the Danube Delta migrate South, being recovered in Bulgaria (in late summer or autumn and Turkey (in winter, with one out of the range record of a bird observed in the UK. The recoveries from abroad originated from either countries around the Baltic Sea (Denmark, Estonia or from Southern Ukraine and Russia. These recoveries date from autumn (mostly October and November and spring months, with one record in December and January each. As a conclusion, we state that there is a possibility that the population increase is fuelled by immigrant birds, but this assumption should be tested by a large scale capture-recapture study, based on colorringing.

  8. Shrub mound formation and stability on semi-arid slopes in the Northern Negev Desert of Israel: A field and simulation study

    NARCIS (Netherlands)

    Buis, E.; Temme, A.J.A.M.; Veldkamp, A.; Boeken, B.; Jongmans, A.G.; Breemen, van N.; Schoorl, J.M.

    2010-01-01

    In semi-arid areas vegetation is scarce and often dominated by individual shrubs on raised mounds. The processes of formation of these mounds are diverse and still debated. Often, shrub mound formation is directly related to the formation of vegetation patterns, thereby assuming that shrub mound

  9. Localised human impacts on the Harataonga coastal landscape, Great Barrier Island, northern New Zealand

    International Nuclear Information System (INIS)

    Horrocks, M.; Nichol, S.; Cockrem, J.; Shane, P.

    2008-01-01

    Here we present results of analyses of sediment profiles and cores, and coprolites, from Harataonga Bay, Great Barrier Island. Using a range of analyses (sedimentological, plant microfossils, parasitological, microbial, and steroids and myoglobin) we concentrate on human impact and reconstruction of the geomorphology and vegetation of the near-shore environments. Two different sub--environments are represented: dunes and alluvial plain. Dune instability coincides with a major increase in disturbance-related plants (especially ground ferns) as a result of forest clearance. The present form of much of the Harataonga dunes and the swamp at the eastern end of the bay is directly a result of human impact, no earlier than 737 ± 178 14 C yr BP. In the record from the alluvial plain of the main Harataonga watercourse, at the western end of the bay, it is difficult to clearly resolve sedimentary inputs that directly relate to human presence in this former tidal inlet that was open to storm surge and stream floods. The only exception is the slopewash materials forming the terrace surface, sediments of which bear pollen consistent with vegetation disturbance. The landforms are natural but the rate at which the tidal inlet was infilled to form a terrace was accelerated by human activity. The nature and timing of the localised human impacts at Harataonga are consistent with those observed elsewhere on Great Barrier Island and mainland New Zealand. Some of our techniques (e.g. bacteria, steroids) are newly applied to coprolites in New Zealand but none provided any useful information because of poor preservation. (author). 34 refs., 13 figs., 3 tabs

  10. Ground level measurement of nuclei from coal development in the northern Great Plains: baseline measurements. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Davis, B. L.; Johnson, L. R.; Sengupta, S.; Yue, P. C.

    1978-11-01

    The Institute of Atmospheric Sciences of the South Dakota School of Mines and Technology has completed 20 months of ambient air sampling at rural and remote sites in a five-state region of the northern Great Plains. Sampling was accomplished by use of a 27-ft motor home laboratory containing living accommodations for a field crew of two. The laboratory was outfitted with a number of instruments for measurement of pollutant parameters: cloud condensation nuclei, ice nuclei, Aitken nuclei, size distribution information for Aitken size particulate, sulfur dioxide, ozone, raindrop size distributions, and pH of precipitation. In addition, an instrumented meteorological tower provided wind speed, wind direction, ambient air temperature, and dew-point temperature. Instruments varied as to durability and success of operation, but better than 90% data retrieval was possible for the entire 20-month sampling study. Analyses of the large quantities of data obtained were not possible under the initial baseline measurement program, but examination of most parameters indicate that the air masses in the northern Great Plains are still relatively clean and are influenced primarily by local sources of contamination rather than large regional sources. Particulate concentrations in these remote areas are representative of mountain stations or clean rural conditions, and sulfur dioxide concentrations are at the threshold of detectability of the instrument. Precipitation is only very slightly acidic, and no significant quantity of amorphous particles (such as coal dust or combustion products) is found in the quantitative analyses of the high-volume filter collections. A summary of ''average'' conditions observed over the study area is tabulated.

  11. Growth-climate relationships across topographic gradients in the northern Great Lakes

    Science.gov (United States)

    Dymond, S.F.; D'Amato, A.W.; Kolka, R.K.; Bolstad, P.V.; Sebestyen, S.D.; Bradford, John B.

    2016-01-01

    Climatic conditions exert important control over the growth, productivity, and distribution of forests, and characterizing these relationships is essential for understanding how forest ecosystems will respond to climate change. We used dendrochronological methods to develop climate–growth relationships for two dominant species, Populus tremuloides (quaking aspen) and Pinus resinosa (red pine), in the upper Great Lakes region to understand how climate and water availability influence annual forest productivity. Trees were sampled along a topographic gradient at the Marcell Experimental Forest (Minnesota, USA) to assess growth response to variations in temperature and different water availability metrics (precipitation, potential evapotranspiration (PET), cumulative moisture index (CMI), and soil water storage). Climatic variables were able to explain 33–58% of the variation in annual growth (as measured by ring-width increment) for quaking aspen and 37–74% of the variation for red pine. Climate–growth relationships were influenced by topography for quaking aspen but not for red pine. Annual ring growth for quaking aspen decreased with June CMI on ridges, decreased with temperature in the November prior to the growing season on sideslopes, and decreased with June PET on toeslopes. Red pine growth increased with increasing July PET across all topographic positions. These results indicate the sensitivity of both quaking aspen and red pine to local climate and show several vulnerabilities of these species to shifts in water supply and temperature because of climate change.

  12. A scheme for the uniform mapping and monitoring of earth resources and environmental complexes: An assessment of natural vegetation, environmental, and crop analogs. [Sierra-Lahontan and Colorado Plateaus, Northern Great Valley (CA), and Louisiana Coastal Plain

    Science.gov (United States)

    Poulton, C. E.; Welch, R. I. (Principal Investigator)

    1975-01-01

    The author has identified the following significant results. A study was performed to develop and test a procedure for the uniform mapping and monitoring of natural ecosystems in the semi-arid and wood regions of the Sierra-Lahontan and Colorado Plateau areas, and for the estimating of rice crop production in the Northern Great Valley (Ca.) and the Louisiana Coastal Plain. ERTS-1 and high flight and low flight aerial photos were used in a visual photointerpretation scheme to identify vegetation complexes, map acreages, and evaluate crop vigor and stress. Results indicated that the vegetation analog concept is valid; that depending on the kind of vegetation and its density, analogs are interpretable at different levels in the hierarchical classification from second to the fourth level. The second level uses physiognomic growth form-structural criteria, and the fourth level uses floristic or taxonomic criteria, usually at generic level. It is recommended that analog comparisons should be made in relatively small test areas where large homogeneous examples can be found of each analog.

  13. Moistening of the northern North American Great Plains enhances land-atmosphere coupling

    Science.gov (United States)

    Gerken, T.; Bromley, G. T.; Stoy, P. C.

    2017-12-01

    Land use change impacts planetary boundary layer processes and regional climate by altering the magnitude and timing of water and energy flux into the atmosphere. In the North American Great Plains (NGP), a decline in the practice of summer fallow on the order of 20 Mha from the 1970s until the present has coincided with a decrease in summertime radiative forcing, on the order of 6 W m-2. MERRA 2 (Modern-Era Retrospective analysis for Research and Applications) for the area near Fort Peck, Montana, (a FLUXNET site established in 2000) shows a decrease of summertime (June-August) sensible heat fluxes ranging from -3.6 to -8.5 W m-2 decade-1, associated with an increase of latent heat fluxes (5.2-9.1 W m-2 decade-1) since the 1980s. Net radiation changed little. The result was a strong decrease of summer Bowen ratios from 1.5-2 in 1980 to approximately 1 in 2015. Findings are consistent with the effects on increased summertime evapotranspiration due to reduction in summer fallow that should lead to smaller Bowen ratios and a larger build-up of moist static energy. We use a mixed-layer (ML) atmospheric modeling framework to further investigate the impact of the surface energy balance on convective development and local land-atmosphere coupling in the NGP. Using summertime eddy covariance data from Fort Peck and atmospheric soundings from the nearby Glasgow airport, we compare the development of modeled ML and lifted condensation level (LCL) to find times of ML exceeding LCL, a necessary but not sufficient condition for the occurrence of convective precipitation. We establish that the ML model adequately captures ML heights and timing of locally triggered convection at the site and that there is a c. 10% increase in modeled convection permitting conditions today compared to 1975-85 in response to ML-moistening and decreasing Bo. We find that growing season land-atmosphere coupling develops from wet preference in May to dry coupling in July and atmospheric suppression

  14. A high 87Sr 86Sr mantle source for low alkali tholeiite, northern Great Basin

    Science.gov (United States)

    Mark, R.K.; Lee, Hu C.; Bowman, H.R.; Asaro, F.; McKee, E.H.; Coats, R.R.

    1975-01-01

    Olivine tholeiites, the youngest Tertiary units (about 8-11 m.y. old) at five widely spaced localities in northeastern Nevada, are geologically related to the basalts of the Snake River Plain, Idaho, to the north and are similar in major element and alkali chemistry to mid-ocean ridge basalts (MORB) and island arc tholeiites. The measured K (1250-3350 ppm), Rb (1??9-6??2 ppm) and Sr (140-240 ppm) concentrations overlap the range reported for MORB. Three of the five samples have low, unfractionated rare earth element (REE) patterns, the other two show moderate light-REE enrichment. Barium concentration is high and variable (100-780 ppm) and does not correlate with the other LIL elements. The rocks have 87Sr/86Sr = 0??7052-0??7076, considerably higher than MORB (~0??702-0??703). These samples are chemically distinct (i.e. less alkalic) from the olivine tholeiites from the adjacent Snake River Plain, but their Sr isotopic compositions are similar. They contain Sr that is distinctly more radiogenic than the basalts from the adjacent Great Basin. About 10 b.y. would be required for the mean measured Rb/Sr (~ 0??02) of these samples to generate, in a closed system, the radiogenic Sr they contain. The low alkali content of these basalts makes crustal contamination an unlikely mechanism. If the magma is uncontaminated, the time-averaged Rb/Sr of the source material must have been ~0??04. A significant decrease in Rb/Sr of the source material (a factor 2??) thus most probably occurred in the relatively recent (1??09 yr) past. Such a decrease of Rb/Sr in the mantle could accompany alkali depletion produced by an episode of partial melting and magma extraction. In contrast, low 87Sr 86Sr ratios indicate that the source material of the mid-ocean ridge basalts may have been depleted early in the Earth's history. ?? 1975.

  15. Impact of Altered Precipitation Patterns on Plant Productivity and Soil Respiration in a Northern Great Plains Grassland

    Science.gov (United States)

    Haase, L.; Flanagan, L. B.

    2017-12-01

    Precipitation patterns are expected to shift towards larger but fewer rain events, with longer intermittent dry periods, associated with climate change. The larger rain events may compensate for and help to mitigate climate change effects on key ecosystem functions such as plant productivity and soil respiration in semi-arid grasslands. We experimentally manipulated the amount and frequency of simulated precipitation added to trenched, treatment plots that were covered by rain shelters, and measured the response in plant productivity and soil respiration in a native, grassland ecosystem near Lethbridge, Alberta. We compared the observed responses to the predictions of a conceptual ecosystem response model developed by Knapp et al. 2008 (BioScience 58: 811-821). Two experiments were conducted during 14 weeks of the growing season from May-August. The first experiment (normal amount) applied total growing season precipitation of 180 mm (climate normal), and the second experiment (reduced amount) applied total precipitation of 90 mm. In both experiments, precipitation was applied at two frequencies, 1 rain event every week (normal frequency) and 1 rain event every two weeks (reduced frequency). In the normal amount experiment, the average rain event was 12.8 mm for the normal frequency treatment and 25.8 mm for the reduced frequency treatment. In the reduced amount experiment, the average rain event was 6.4 mm for the normal frequency treatment and 12.8 mm for the reduced frequency treatment. We hypothesized that larger but fewer rain events would result in increased plant productivity and soil respiration for both experiments. Plant greenness values calculated from digital photographs were used as a proxy for plant productivity, and showed significantly higher values for the normal vs. reduced amount experiment. Soil respiration rate also showed significantly higher values for the normal vs. reduced amount experiment. No significant treatment effect could be detected

  16. Task 50 - deposition of lignites in the Fort Union Group and related strata of the northern Great Plains

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, J.H.; Roth, B.; Kihm, A.J.

    1997-08-11

    Late Cretaceous, Paleocene, and early Eocene geologic and paleontologic studies were undertaken in western North Dakota, eastern and south-central Montana, and northwestern and northeastern Wyoming. These study areas comprise the Williston, Bighorn, and Powder River Basins, all of which contain significant lignite resources. Research was undertaken in these basins because they have the best geologic sections and fossil record for the development of a chronostratigraphic (time-rock) framework for the correlation of lignite beds and other economic resources. A thorough understanding of the precise geologic age of the deposition of sediments permits a powerful means of interpreting the record of geologic events across the northern Great Plains. Such an understanding allows for rigorous interpretation of paleoenviromnents and estimates of resource potential and quality in this area of economically significant deposits. This work is part of ongoing research to document change in the composition of molluscan fossil faunas to provide a paleoenvironmentally sensitive independent means of interpreting time intervals of brief duration during the Late Cretaceous, Paleocene, and Eocene. This study focuses on the record of mollusks and, to a lesser extent, mammals in the (1) Hell Creek-Tullock Formations, which include the Cretaceous-Paleocene boundary, in the western portion of the Williston Basin, Montana; (2) uppermost Cretaceous, Paleocene, and lowermost Eocene strata in western North Dakota, which -includes the last interior seaway in North Dakota; (3) upper Paleocene and lowermost Eocene of the northern portion of the Bighorn Basin of south-central Montana and northwestern Wyoming; and (4) Powder River Basin of northeastern Wyoming and southeastern Montana. The geologic record provides different physical and paleontological information to aid in interpreting the geologic record through the study interval.

  17. At Home in the Great Northern Wilderness: African Americans and Freedom’s Ecology in the Adirondacks, 1846-1859

    Directory of Open Access Journals (Sweden)

    Daegan Miller

    2013-05-01

    Full Text Available In the fall of 1846, the first of 3,000 African American settlers set foot on their 40-acre plots in the Great Northern Wilderness of New York State, a place we now call the “forever wild” wilderness of the Adirondack State Park. These black settlers were the initial wave of a social experiment meant to destroy both slavery and, more generally, racism throughout the entire United States through the redemptive practice of a utopian agrarianism. The settlers understood that nature and culture, wilderness and society, were thickly, dialectically intertwined. And they weren’t alone: their efforts were seeded by the white abolitionist, Gerrit Smith; fertilized by the utopian socialist communes that covered the Northeast in the 1840s; and nurtured by abolitionists, both black and white. To United States environmental history, I add two threads less frequently seen: African American history and an intellectual history of radical politics. Following these threads has led me beyond the disciplinary confines of history and into larger debates about the cultural politics of wilderness. In this article I argue that the critical wilderness paradigm currently reigning both in and beyond historical scholarship has obscured nuanced, sometimes radical visions of the natural world. Instead of an ironic, deconstructed notion of a troubling wilderness, I suggest another heuristic, the ecology of freedom, which highlights past contingency and hope, and can furthermore help guide our present efforts, both scholastic and activist, to find an honorable, just way of living on the earth.

  18. Using stable isotopes to understand hydrochemical processes in and around a Prairie Pothole wetland in the Northern Great Plains, USA

    International Nuclear Information System (INIS)

    Mills, Christopher T.; Goldhaber, Martin B.; Stricker, Craig A.; Holloway, JoAnn M.; Morrison, Jean M.; Ellefsen, Karl J.; Rosenberry, Donald O.; Thurston, Roland S.

    2011-01-01

    Highlights: → A stable isotope study of the hydrochemistry of a Prairie Pothole wetland system. → δ 18 O H2O and δ 2 H H2O values show salt concentration by transpiration at wetland edge. → A range of δ 34 S SO4 values indicate SO 4 source and reduction processes. → Isotopic mixing lines show interaction of surface and groundwater at wetland edge. - Abstract: Millions of internally drained wetland systems in the Prairie Potholes region of the northern Great Plains (USA and Canada) provide indispensable habitat for waterfowl and a host of other ecosystem services. The hydrochemistry of these systems is complex and a crucial control on wetland function, flora and fauna. Wetland waters can have high concentrations of SO 4 2- due to the oxidation of large amounts of pyrite in glacial till that is in part derived from the Pierre shale. Water chemistry including δ 18 O H2O , δ 2 H H2O , and δ 34 S SO4 values, was determined for groundwater, soil pore water, and wetland surface water in and around a discharge wetland in North Dakota. The isotopic data for the first time trace the interaction of processes that affect wetland chemistry, including open water evaporation, plant transpiration, and microbial SO 4 reduction.

  19. Land-use change reduces habitat suitability for supporting managed honey bee colonies in the Northern Great Plains

    Science.gov (United States)

    Otto, Clint R.; Roth, Cali; Carlson, Benjamin; Smart, Matthew

    2016-01-01

    Human reliance on insect pollination services continues to increase even as pollinator populations exhibit global declines. Increased commodity crop prices and federal subsidies for biofuel crops, such as corn and soybeans, have contributed to rapid land-use change in the US Northern Great Plains (NGP), changes that may jeopardize habitat for honey bees in a part of the country that supports >40% of the US colony stock. We investigated changes in biofuel crop production and grassland land covers surrounding ∼18,000 registered commercial apiaries in North and South Dakota from 2006 to 2014. We then developed habitat selection models to identify remotely sensed land-cover and land-use features that influence apiary site selection by Dakota beekeepers. Our study demonstrates a continual increase in biofuel crops, totaling 1.2 Mha, around registered apiary locations in North and South Dakota. Such crops were avoided by commercial beekeepers when selecting apiary sites in this region. Furthermore, our analysis reveals how grasslands that beekeepers target when selecting commercial apiary locations are becoming less common in eastern North and South Dakota, changes that may have lasting impact on pollinator conservation efforts. Our study highlights how land-use change in the NGP is altering the landscape in ways that are seemingly less conducive to beekeeping. Our models can be used to guide future conservation efforts highlighted in the US national pollinator health strategy by identifying areas that support high densities of commercial apiaries and that have exhibited significant land-use changes.

  20. Correlations of soil-gas and indoor radon with geology in glacially derived soils of the northern Great Plains

    International Nuclear Information System (INIS)

    Schumann, R.R.; Owen, D.E.; Peake, R.T.; Schmidt, K.M.

    1990-01-01

    This paper reports that a higher percentage of homes in parts of the northern Great Plains underlain by soils derived from continental glacial deposits have elevated indoor radon levels (greater than 4 pCi/L) than any other area in the country. Soil-gas radon concentrations, surface radioactivity, indoor radon levels, and soil characteristics were studied in areas underlain by glacially-derived soils in North Dakota and Minnesota to examine the factors responsible for these elevated levels. Clay-rich till soils in North Dakota have generally higher soil-gas radon levels, and correspondingly higher indoor radon levels, than the sandy till soils common to west-central Minnesota. Although the proportions of homes with indoor radon levels greater than 4 pCi/L are similar in both areas, relatively few homes underlain by sandy tills have screening indoor radon levels greater than 20 pCi/L, whereas a relatively large proportion of homes underlain by clayey tills have screening indoor radon levels exceeding 20 pCi/L. The higher radon levels in North Dakota are likely due to enhanced emanation from the smaller grains and to relatively higher soil radium concentrations in the clay-rich soils, whereas the generally higher permeability of the sandy till soils in Minnesota allows soil gas to be drawn into structures from a larger source volume, increasing indoor radon levels in these areas

  1. EXAMINATION OF THE SOLVENCY OF ENTERPRISES DEALING WITH ACCOMMODATION SERVICE PROVIDING IN THE NORTHERN GREAT PLAIN REGION

    Directory of Open Access Journals (Sweden)

    Veronika FENYVES

    2016-07-01

    Full Text Available One of the most important characteristics of tourism, as an economic and social phenomenon is that it has become a leading sector of the Hungarian economy. The importance of this sector is faithfully reflected by the fact that tourism gives nearly 9% of the GDP. Of course, aim of the enterprises of this type is the liquidity as well i.e. to maintain the short-term solvency that is essential for the long-term successful and smooth operation. The other aim of enterprises is to be solvent for the long-term as well, furthermore, to increase the corporate value and to maximize the ownership value. In our treatise, we have carried out the financial analysis and bankruptcy prediction of those enterprises providing accommodation service which are the biggest from the point of view of employment in the Northern Great Plain region. We think that, due to seasonality, even greater emphasis shall be placed on this area where useful information can be obtained from and the results of bankruptcy model can also provide further useful information and ”problem alerts”.

  2. Carbonate microbialites and hardgrounds from Manito Lake, an alkaline, hypersaline lake in the northern Great Plains of Canada

    Science.gov (United States)

    Last, Fawn M.; Last, William M.; Halden, Norman M.

    2010-03-01

    Manito Lake is a large, perennial, Na-SO 4 dominated saline to hypersaline lake located in the northern Great Plains of western Canada. Significant water level decrease over the past several decades has led to reduction in volume and surface area, as well as an increase in salinity. The salinity has increased from 10 ppt to about 50 ppt TDS. This decrease in water level has exposed large areas of nearshore microbialites. These organogenic structures range in size from several cm to over a meter and often form large bioherms several meters high. They have various external morphologies, vary in mineralogical composition, and show a variety of internal fabrics from finely laminated to massive. In addition to microbiolities and bioherms, the littoral zone of Manito Lake contains a variety of carbonate hardgrounds, pavements, and cemented clastic sediments. Dolomite and aragonite are the most common minerals found in these shoreline structures, however, calcite after ikaite, monohydrocalcite, magnesian calcite, and hydromagnesite are also present. The dolomite is nonstoichiometric and calcium-rich; the magnesian calcite has about 17 mol% MgCO 3. AMS radiocarbon dating of paired organic matter and endogenic carbonate material confirms little or no reservoir affect. Although there is abundant evidence for modern carbonate mineral precipitation and microbialite formation, most of the larger microbialites formed between about 2300 and 1000 cal BP, whereas the hardgrounds, cements, and laminated crusts formed about 1000-500 cal BP.

  3. Coal Development in the Northern Great Plains. The Impact on Revenues of State and Local Governments. Agricultural Economic Report No. 394.

    Science.gov (United States)

    Stinson, Thomas F.; Voelker, Stanley W.

    Development of Northern Great Plains coal resources will create new demands for state and local government services. Development will also produce increased government revenues. Special taxes on coal production have been enacted in Montana, North Dakota, and Wyoming in order to ensure that state and local governments receive sufficient revenues to…

  4. Communication received from the United Kingdom of Great Britain and Northern Ireland concerning its national holdings of civil high enriched uranium

    International Nuclear Information System (INIS)

    1998-01-01

    The document reproduces the text of the note verbale and its attachment dated 1 July 1998 received by the Director General of the IAEA from the Permanent Mission to the IAEA of the United Kingdom of Great Britain and Northern Ireland, making available information on its national holdings of civil high enriched uranium as of 31 December 1997

  5. Composition and seasonal phenology of a nonindigenous root-feeding weevil (Coleoptera: Curculionidae) complex in northern hardwood forests in the Great Lakes Region

    Science.gov (United States)

    R. A. Pinski; W. J. Mattson; K. F. Raffa

    2005-01-01

    Phyllobius oblongus (L.), Polydrusus sericeus (Schaller), and Sciaphilus asperatus (Bonsdorff) comprise a complex of nonindigenous root-feeding weevils in northern hardwood forests of the Great Lakes region. Little is known about their detailed biology, seasonality, relative abundance, and distribution patterns....

  6. Vulnerability of grazing and confined livestock in the Northern Great Plains to projected mid- and late-twenty-first century climate

    Science.gov (United States)

    The Northern Great Plains (NGP) region of the United States – which comprises Montana, Wyoming, Colorado, North Dakota, South Dakota and Nebraska – is a largely rural area that provides important agricultural and ecological services, including biological diversity. The region contains 25% of the Nat...

  7. Ages, geochemistry and tectonic implications of the Cambrian igneous rocks in the northern Great Xing'an Range, NE China

    Science.gov (United States)

    Feng, Zhiqiang; Liu, Yongjiang; Li, Yanrong; Li, Weimin; Wen, Quanbo; Liu, Binqiang; Zhou, Jianping; Zhao, Yingli

    2017-08-01

    The Xinlin-Xiguitu suture zone, located in the Great Xing'an Range, NE China, in the eastern segment of the Central Asian Orogenic Belt (CAOB), represents the boundary between the Erguna and Xing'an micro-continental blocks. The exact location of the Xinlin-Xiguitu suture zone has been debated, especially, the location of the northern extension of the suture zone. In this study, based on a detailed field, geochemical, geochronological and Sr-Nd-Hf isotope study, we focus our work on the Cambrian igneous rocks in the Erguna-Xing'an block. The Xinglong granitoids, mainly include ∼520 Ma diorite, ∼470 Ma monzogranite and ∼480 Ma pyroxene diorite. The granitoids show medium to high-K calc-alkaline series characteristics with post-collision granite affinity. The circa 500 Ma granitoids have low εHf (t) values (-16.6 to +2.2) and ancient two-stage model (TDM2) ages between 1317 Ma and 2528 Ma. These results indicate the primary magmas of the Xinglong granitoids were probably derived from the partial melting of a dominantly Paleo-Mesoproterozoic ;old; crustal source with possible different degrees of addition of juvenile materials, and formed in a post-collision tectonic setting after the amalgamation of the Erguna and Xing'an blocks. Compared with the Xinglong granitoids, the Duobaoshan igneous rocks are consisted of the approximately coeval rhyolitic tuffs (491 ± 5 Ma) and ultramafic intrusions (497 ± 5 Ma) within the Duobaoshan Formation. They are generally enriched in large ion lithophile elements (LILEs) and depleted in high field strength elements (HFSEs; e.g., Nb, Ta, and Ti), consistent with the geochemistry of igneous rocks from island arcs or active continental margins. The ultramafic rocks have high positive εHf (t) values (+1.3 to +15) and εNd (t) (+1.86 to +2.28), and relatively young two-stage model (TDM2) ages and low initial 87Sr/86Sr ratios (0.70628-0.70853), indicating the partial melting of a depleted mantle source from a subducted slab in

  8. Model-based scenario planning to inform climate change adaptation in the Northern Great Plains—Final report

    Science.gov (United States)

    Symstad, Amy J.; Miller, Brian W.; Friedman, Jonathan M.; Fisichelli, Nicholas A.; Ray, Andrea J.; Rowland, Erika; Schuurman, Gregor W.

    2017-12-18

    Public SummaryWe worked with managers in two focal areas to plan for the uncertain future by integrating quantitative climate change scenarios and simulation modeling into scenario planning exercises.In our central North Dakota focal area, centered on Knife River Indian Villages National Historic Site, managers are concerned about how changes in flood severity and growing conditions for native and invasive plants may affect archaeological resources and cultural landscapes associated with the Knife and Missouri Rivers. Climate projections and hydrological modeling based on those projections indicate plausible changes in spring and summer soil moisture ranging from a 7 percent decrease to a 13 percent increase and maximum winter snowpack (important for spring flooding) changes ranging from a 13 percent decrease to a 47 percent increase. Facilitated discussions among managers and scientists exploring the implications of these different climate scenarios for resource management revealed potential conflicts between protecting archeological sites and fostering riparian cottonwood forests. The discussions also indicated the need to prioritize archeological sites for excavation or protection and culturally important plant species for intensive management attention.In our southwestern South Dakota focal area, centered on Badlands National Park, managers are concerned about how changing climate will affect vegetation production, wildlife populations, and erosion of fossils, archeological artifacts, and roads. Climate scenarios explored by managers and scientists in this focal area ranged from a 13 percent decrease to a 33 percent increase in spring precipitation, which is critical to plant growth in the northern Great Plains region, and a slight decrease to a near doubling of intense rain events. Facilitated discussions in this focal area concluded that greater effort should be put into preparing for emergency protection, excavation, and preservation of exposed fossils or

  9. Accessing the uncertainties of seismic velocity and anisotropy structure of Northern Great Plains using a transdimensional Bayesian approach

    Science.gov (United States)

    Gao, C.; Lekic, V.

    2017-12-01

    Seismic imaging utilizing complementary seismic data provides unique insight on the formation, evolution and current structure of continental lithosphere. While numerous efforts have improved the resolution of seismic structure, the quantification of uncertainties remains challenging due to the non-linearity and the non-uniqueness of geophysical inverse problem. In this project, we use a reverse jump Markov chain Monte Carlo (rjMcMC) algorithm to incorporate seismic observables including Rayleigh and Love wave dispersion, Ps and Sp receiver function to invert for shear velocity (Vs), compressional velocity (Vp), density, and radial anisotropy of the lithospheric structure. The Bayesian nature and the transdimensionality of this approach allow the quantification of the model parameter uncertainties while keeping the models parsimonious. Both synthetic test and inversion of actual data for Ps and Sp receiver functions are performed. We quantify the information gained in different inversions by calculating the Kullback-Leibler divergence. Furthermore, we explore the ability of Rayleigh and Love wave dispersion data to constrain radial anisotropy. We show that when multiple types of model parameters (Vsv, Vsh, and Vp) are inverted simultaneously, the constraints on radial anisotropy are limited by relatively large data uncertainties and trade-off strongly with Vp. We then perform joint inversion of the surface wave dispersion (SWD) and Ps, Sp receiver functions, and show that the constraints on both isotropic Vs and radial anisotropy are significantly improved. To achieve faster convergence of the rjMcMC, we propose a progressive inclusion scheme, and invert SWD measurements and receiver functions from about 400 USArray stations in the Northern Great Plains. We start by only using SWD data due to its fast convergence rate. We then use the average of the ensemble as a starting model for the joint inversion, which is able to resolve distinct seismic signatures of

  10. Enhanced sediment delivery in a changing climate in semi-arid mountain basins: Implications for water resource management and aquatic habitat in the northern Rocky Mountains

    Science.gov (United States)

    Jaime R. Goode; Charles H. Luce; John M. Buffington

    2012-01-01

    The delivery and transport of sediment through mountain rivers affects aquatic habitat and water resource infrastructure. While climate change is widely expected to produce significant changes in hydrology and stream temperature, the effects of climate change on sediment yield have received less attention. In the northern Rocky Mountains, we expect climate change to...

  11. Land use in the Northern Great Plains region of the U.S. influences the survival and productivity of honey bee colonies

    Science.gov (United States)

    Smart, Matthew; Pettis, Jeff S.; Euliss, Ned H. Jr.; Spivak, Marla S.

    2016-01-01

    The Northern Great Plains region of the US annually hosts a large portion of commercially managed U.S. honey bee colonies each summer. Changing land use patterns over the last several decades have contributed to declines in the availability of bee forage across the region, and the future sustainability of the region to support honey bee colonies is unclear. We examined the influence of varying land use on the survivorship and productivity of honey bee colonies located in six apiaries within the Northern Great Plains state of North Dakota, an area of intensive agriculture and high density of beekeeping operations. Land use surrounding the apiaries was quantified over three years, 2010–2012, and survival and productivity of honey bee colonies were determined in response to the amount of bee forage land within a 3.2-km radius of each apiary. The area of uncultivated forage land (including pasture, USDA conservation program fields, fallow land, flowering woody plants, grassland, hay land, and roadside ditches) exerted a positive impact on annual apiary survival and honey production. Taxonomic diversity of bee-collected pollen and pesticide residues contained therein varied seasonally among apiaries, but overall were not correlated to large-scale land use patterns or survival and honey production. The predominant flowering plants utilized by honey bee colonies for pollen were volunteer species present in unmanaged (for honey bees), and often ephemeral, lands; thus placing honey bee colonies in a precarious situation for acquiring forage and nutrients over the entire growing season. We discuss the implications for land management, conservation, and beekeeper site selection in the Northern Great Plains to adequately support honey bee colonies and insure long term security for pollinator-dependent crops across the entire country.

  12. Professor Sir Mark Walport Government Chief Scientific Adviser Head of Government Science and Engineering Profession Chief Executive Designate of UK Research and Innovation United Kingdom of Great Britain and Northern Ireland

    CERN Multimedia

    Bennett, Sophia Elizabeth

    2017-01-01

    Professor Sir Mark Walport Government Chief Scientific Adviser Head of Government Science and Engineering Profession Chief Executive Designate of UK Research and Innovation United Kingdom of Great Britain and Northern Ireland

  13. The text of the Agreement of 22 September 1982 between Chile and the Agency for the application of safeguards in connection with the supply of nuclear material from the United Kingdom of Great Britain and Northern Ireland

    International Nuclear Information System (INIS)

    1983-07-01

    The full text of the agreement of 22 September 1982 between Chile and the Agency for the application of safeguards to nuclear material supplied from the United Kingdom of Great Britain and Northern Ireland is presented

  14. 20 January 2014 - Members of the Regional Assemblies and Parliaments United Kingdom of Great Britain and Northern Ireland visiting the LHC tunnel at Point 8 with Technology Department, Vacuum, Surfaces and Coatings Group P. Cruikshank.

    CERN Document Server

    Pantelia, Anna

    2014-01-01

    20 January 2014 - Members of the Regional Assemblies and Parliaments United Kingdom of Great Britain and Northern Ireland visiting the LHC tunnel at Point 8 with Technology Department, Vacuum, Surfaces and Coatings Group P. Cruikshank.

  15. Her Excellency Mrs Sarah Gillett Her Majesty's Ambassador to the Swiss Confederation United Kingdom of Great Britain and Northern Ireland on the occasion of the Antony Gormley sculpture unveiling ceremony Wednesday 7th December 2011

    CERN Document Server

    Maximilien Brice

    2011-01-01

    Her Excellency Mrs Sarah Gillett Her Majesty's Ambassador to the Swiss Confederation United Kingdom of Great Britain and Northern Ireland on the occasion of the Antony Gormley sculpture unveiling ceremony Wednesday 7th December 2011

  16. Exploiting differential vegetation phenology for satellite-based mapping of semiarid grass vegetation in the southwestern United States and northern Mexico

    Science.gov (United States)

    Dye, Dennis G.; Middleton, Barry R.; Vogel, John M.; Wu, Zhuoting; Velasco, Miguel G.

    2016-01-01

    We developed and evaluated a methodology for subpixel discrimination and large-area mapping of the perennial warm-season (C4) grass component of vegetation cover in mixed-composition landscapes of the southwestern United States and northern Mexico. We describe the methodology within a general, conceptual framework that we identify as the differential vegetation phenology (DVP) paradigm. We introduce a DVP index, the Normalized Difference Phenometric Index (NDPI) that provides vegetation type-specific information at the subpixel scale by exploiting differential patterns of vegetation phenology detectable in time-series spectral vegetation index (VI) data from multispectral land imagers. We used modified soil-adjusted vegetation index (MSAVI2) data from Landsat to develop the NDPI, and MSAVI2 data from MODIS to compare its performance relative to one alternate DVP metric (difference of spring average MSAVI2 and summer maximum MSAVI2), and two simple, conventional VI metrics (summer average MSAVI2, summer maximum MSAVI2). The NDPI in a scaled form (NDPIs) performed best in predicting variation in perennial C4 grass cover as estimated from landscape photographs at 92 sites (R2 = 0.76, p landscapes of the Southwest, and potentially for monitoring of its response to drought, climate change, grazing and other factors, including land management. With appropriate adjustments, the method could potentially be used for subpixel discrimination and mapping of grass or other vegetation types in other regions where the vegetation components of the landscape exhibit contrasting seasonal patterns of phenology.

  17. Protocol Additional to the agreement between the United Kingdom of Great Britain and Northern Ireland, the European Atomic Energy Community and the International Atomic Energy Agency for the application of safeguards in the United Kingdom of Great Britain and Northern Ireland in connection with the Treaty on the Non-Proliferation of Nuclear Weapons

    International Nuclear Information System (INIS)

    2005-01-01

    The text of the Protocol Additional to the Agreement between the United Kingdom of Great Britain and Northern Ireland, the European Atomic Energy Community and the International Atomic Energy Agency for the Application of Safeguards in the United Kingdom of Great Britain and Northern Ireland in Connection with the Treaty on the Non-Proliferation of Nuclear Weapons is reproduced in the Annex to this document for the information of all Members. The Additional Protocol was approved by the Board of Governors on 11 June 1998. It was signed in Vienna on 22 September 1998. Pursuant to Article 17 of the Additional Protocol, the Protocol entered into force on 30 April 2004, the date on which the Agency received written notification that the European Atomic Energy Community and the United Kingdom had met their respective internal requirements for entry into force

  18. Analyses of infrequent (quasi-decadal) large groundwater recharge events in the northern Great Basin: Their importance for groundwater availability, use, and management

    Science.gov (United States)

    Masbruch, Melissa D.; Rumsey, Christine; Gangopadhyay, Subhrendu; Susong, David D.; Pruitt, Tom

    2016-01-01

    There has been a considerable amount of research linking climatic variability to hydrologic responses in the western United States. Although much effort has been spent to assess and predict changes in surface water resources, little has been done to understand how climatic events and changes affect groundwater resources. This study focuses on characterizing and quantifying the effects of large, multiyear, quasi-decadal groundwater recharge events in the northern Utah portion of the Great Basin for the period 1960–2013. Annual groundwater level data were analyzed with climatic data to characterize climatic conditions and frequency of these large recharge events. Using observed water-level changes and multivariate analysis, five large groundwater recharge events were identified with a frequency of about 11–13 years. These events were generally characterized as having above-average annual precipitation and snow water equivalent and below-average seasonal temperatures, especially during the spring (April through June). Existing groundwater flow models for several basins within the study area were used to quantify changes in groundwater storage from these events. Simulated groundwater storage increases per basin from a single recharge event ranged from about 115 to 205 Mm3. Extrapolating these amounts over the entire northern Great Basin indicates that a single large quasi-decadal recharge event could result in billions of cubic meters of groundwater storage. Understanding the role of these large quasi-decadal recharge events in replenishing aquifers and sustaining water supplies is crucial for long-term groundwater management.

  19. Opportunistic sampling to quantify plastics in the diet of unfledged Black Legged Kittiwakes (Rissa tridactyla), Northern Fulmars (Fulmarus glacialis) and Great Cormorants (Phalacrocorax carbo).

    Science.gov (United States)

    Acampora, Heidi; Newton, Stephen; O'Connor, Ian

    2017-06-30

    Seabirds can interact with marine litter, mainly by entanglement or ingestion. The ingestion of plastics can lead to starvation or physical damage to the digestive tract. For chicks, it could additionally lead to reduced growth, affecting survival and fledging. This study quantified the ingestion of plastics by seabird chicks via an opportunistic sampling strategy. When ringing is carried out at colonies, birds may spontaneously regurgitate their stomach contents due to the stress or as a defence mechanism. Regurgitates were collected from nestlings of three different species: Black-legged Kittiwake (Rissa tridactyla, n=38), Northern Fulmar (Fulmarus glacialis, n=14) and Great Cormorant (Phalacrocorax carbo, n=28). Plastic was present in all species, with the highest frequency of occurrence (FO) in Northern Fulmar chicks (28.6%), followed by Black-legged Kittiwakes (7.9%) and Great Cormorants (7.1%). The observed load of plastics on chicks, which have not yet left the nest, highlights the pervasive nature of plastic pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Paleoecology of a Northern Michigan Lake and the relationship among climate, vegetation, and Great Lakes water levels

    Science.gov (United States)

    Booth, R.K.; Jackson, S.T.; Thompson, T.A.

    2002-01-01

    We reconstructed Holocene water-level and vegetation dynamics based on pollen and plant macrofossils from a coastal lake in Upper Michigan. Our primary objective was to test the hypothesis that major fluctuations in Great Lakes water levels resulted in part from climatic changes. We also used our data to provide temporal constraints to the mid-Holocene dry period in Upper Michigan. From 9600 to 8600 cal yr B.P. a shallow, lacustrine environment characterized the Mud Lake basin. A Sphagnum-dominated wetland occupied the basin during the mid-Holocene dry period (???8600 to 6600 cal yr B.P.). The basin flooded at 6600 cal yr B.P. as a result of rising water levels associated with the onset of the Nipissing I phase of ancestral Lake Superior. This flooding event occured contemporaneously with a well-documented regional expansion of Tsuga. Betula pollen increased during the Nipissing II phase (4500 cal yr B.P.). Macrofossil evidence from Mud Lake suggests that Betula alleghaniensis expansion was primarily responsible for the rising Betula pollen percentages. Major regional and local vegetational changes were associated with all the major Holocene highstands of the western Great Lakes (Nipissing I, Nipissing II, and Algoma). Traditional interpretations of Great Lakes water-level history should be revised to include a major role of climate. ?? 2002 University of Washington.

  1. Lower Mesophotic Coral Communities (60-125 m Depth of the Northern Great Barrier Reef and Coral Sea.

    Directory of Open Access Journals (Sweden)

    Norbert Englebert

    Full Text Available Mesophotic coral ecosystems in the Indo-Pacific remain relatively unexplored, particularly at lower mesophotic depths (≥60 m, despite their potentially large spatial extent. Here, we used a remotely operated vehicle to conduct a qualitative assessment of the zooxanthellate coral community at lower mesophotic depths (60-125 m at 10 different locations in the Great Barrier Reef Marine Park and the Coral Sea Commonwealth Marine Reserve. Lower mesophotic coral communities were present at all 10 locations, with zooxanthellate scleractinian corals extending down to ~100 metres on walls and ~125 m on steep slopes. Lower mesophotic coral communities were most diverse in the 60-80 m zone, while at depths of ≥100 m the coral community consisted almost exclusively of the genus Leptoseris. Collections of coral specimens (n = 213 between 60 and 125 m depth confirmed the presence of at least 29 different species belonging to 18 genera, including several potential new species and geographic/depth range extensions. Overall, this study highlights that lower mesophotic coral ecosystems are likely to be ubiquitous features on the outer reefs of the Great Barrier Reef and atolls of the Coral Sea, and harbour a generic and species richness of corals that is much higher than thus far reported. Further research efforts are urgently required to better understand and manage these ecosystems as part of the Great Barrier Reef Marine Park and Coral Sea Commonwealth Marine Reserve.

  2. Hydrologic variability in the Red River of the North basin at the eastern margin of the northern Great Plains

    International Nuclear Information System (INIS)

    Wiche, G.J.

    1991-01-01

    The temporal and spatial variations in streamflow in the Red River of the North basin on the eastern margin of the Great Plains are described and related to the various climatic conditions associated with the flows. The Red River drains about 290,000 square kilometers in parts of Minnesota, South Dakota, North Dakota, Saskatchewan and Manitoba, and a 200 year flood history is available from documents of fur traders, explorers and missionaries, as well as from gauging-station records. The coefficient of variation of mean annual streamflow ranges from ca 110% for streams in the southern and western parts of the Assiniboine River basin to ca 50% for streams along the eastern margin of the Red River of the North basin. Decadal streamflow variability is great in the Red River of the North basin, with mean annual streamflow for the 10 years ending 1940 of 489 cubic hectometers and for the 10 years ending 1975 of 3,670 cubic hectometers. Construction of the Rafferty Reservoir on the Souris River and the Almeda Reservoir on Moose Mountain Creek will cause changes in water quality in the Souris River, with most problems occurring during protracted low flow conditions

  3. National coal resource assessment non-proprietary data: Location, stratigraphy, and coal quality for selected tertiary coal in the Northern Rocky Mountains and Great Plains region

    Science.gov (United States)

    Flores, Romeo M.; Ochs, A.M.; Stricker, G.D.; Ellis, M.S.; Roberts, S.B.; Keighin, C.W.; Murphy, E.C.; Cavaroc, V.V.; Johnson, R.C.; Wilde, E.M.

    1999-01-01

    One of the objectives of the National Coal Resource Assessment in the Northern Rocky Mountains and Great Plains region was to compile stratigraphic and coal quality-trace-element data on selected and potentially minable coal beds and zones of the Fort Union Formation (Paleocene) and equivalent formations. In order to implement this objective, drill-hole information was compiled from hard-copy and digital files of the: (1) U.S. Bureau of Land Management (BLM) offices in Casper, Rawlins, and Rock Springs, Wyoming, and in Billings, Montana, (2) State geological surveys of Montana, North Dakota, and Wyoming, (3) Wyoming Department of Environmental Quality in Cheyenne, (4) U.S. Office of Surface Mining in Denver, Colorado, (5) U.S. Geological Survey, National Coal Resource Data System (NCRDS) in Reston, Virginia, (6) U.S. Geological Survey coal publications, (7) university theses, and (8) mining companies.

  4. Evaluation of Electromagnetic Induction to Characterize and Map Sodium-Affected Soils in the Northern Great Plains of the United States

    Science.gov (United States)

    Brevik, E. C.; Heilig, J.; Kempenich, J.; Doolittle, J.; Ulmer, M.

    2012-04-01

    Sodium-affected soils (SAS) cover over 4 million hectares in the Northern Great Plains of the United States. Improving the classification, interpretation, and mapping of SAS is a major goal of the United States Department of Agriculture-Natural Resource Conservation Service (USDA-NRCS) as Northern Great Plains soil surveys are updated. Apparent electrical conductivity (ECa) as measured with ground conductivity meters has shown promise for mapping SAS, however, this use of this geophysical tool needs additional evaluation. This study used an EM-38 MK2-2 meter (Geonics Limited, Mississauga, Ontario), a Trimble AgGPS 114 L-band DGPS (Trimble, Sunnyvale, CA) and the RTmap38MK2 program (Geomar Software, Inc., Mississauga, Ontario) on an Allegro CX field computer (Juniper Systems, North Logan, UT) to collect, observe, and interpret ECa data in the field. The ECa map generated on-site was then used to guide collection of soil samples for soil characterization and to evaluate the influence of soil properties in SAS on ECa as measured with the EM-38MK2-2. Stochastic models contained in the ESAP software package were used to estimate the SAR and salinity levels from the measured ECa data in 30 cm depth intervals to a depth of 90 cm and for the bulk soil (0 to 90 cm). This technique showed promise, with meaningful spatial patterns apparent in the ECa data. However, many of the stochastic models used for salinity and SAR for individual depth intervals and for the bulk soil had low R-squared values. At both sites, significant variability in soil clay and water contents along with a small number of soil samples taken to calibrate the ECa values to soil properties likely contributed to these low R-squared values.

  5. [Responses of boreal forest landscape in northern Great Xing'an Mountains of Northeast China to climate change].

    Science.gov (United States)

    Li, Xiao-Na; He, Hong-Shi; Wu, Zhi-Wei; Liang, Yu

    2012-12-01

    With the combination of forest landscape model (LANDIS) and forest gap model (LINKAGES), this paper simulated the effects of climate change on the boreal forest landscape in the Great Xing'an Mountains, and compared the direct effects of climate change and the effects of climate warming-induced fires on the forest landscape. The results showed that under the current climate conditions and fire disturbances, the forest landscape in the study area could maintain its dynamic balance, and Larix gmelinii was still the dominant tree species. Under the future climate and fire disturbances scenario, the distribution area of L. gmelinii and Pinus pumila would be decreased, while that of Betula platyphylla, Populus davidiana, Populus suaveolens, Chosenia arbutifolia, and Pinus sylvestris var. mongolica would be increased, and the forest fragmentation and forest diversity would have an increase. The changes of the forest landscape lagged behind climate change. Climate warming would increase the growth of most tree species except L. gmelinii, while the increased fires would increase the distribution area of P. davidiana, P. suaveolens, and C. arbutifolia and decrease the distribution area of L. gmelinii, P. sylvestris var. mongolica, and P. pumila. The effects of climate warming-induced fires on the forest landscape were almost equal to the direct effects of climate change, and aggravated the direct effects of climate change on forest composition, forest landscape fragmentation, and forest landscape diversity.

  6. 6 March 2013 - Committee for Employment and Learning, Northern Ireland Legislative Assembly, United Kingdom of Great Britain and Northern Ireland in the LHC tunnel and visiting the LHCb experiment at LHC Point 8. Director for Accelerators and Technology S. Myers with Vice-Chair T. Buchanan.

    CERN Multimedia

    Anna Pantelia

    2013-01-01

    6 March 2013 - Committee for Employment and Learning, Northern Ireland Legislative Assembly, United Kingdom of Great Britain and Northern Ireland in the LHC tunnel and visiting the LHCb experiment at LHC Point 8. Director for Accelerators and Technology S. Myers with Vice-Chair T. Buchanan.

  7. Developments Related to Tourism and Their Effects in Debrecen Following the Turn of the Millennium (Northern Great Plain Region, Hungary Success Or Failure?

    Directory of Open Access Journals (Sweden)

    Mária Vasvári

    2013-04-01

    Full Text Available The present paper focuses on the developments related to tourism and their effects in Debrecen, the largest city in the Northern Great Plain Region most of all in the time period after the country joining the European Union. The tourist industrial development regarding the infrastructure and supra-structure inDebrecen is presented. These developed further the traditionally popular attractions (Great Forest of the city. Relationship between the demand and reception conditions are described reflecting statistic data and the role of Debrecen in the market is analysed in relation to several other greater towns of the country. Data reveal that the number of visitors did not increase despite the developments related to tourism in the years following the turn of the millennium, even so it decreased after 2008 similarly to other greater towns of the country. Our questionnaire survey performed among the inhabitants and visitors as well revealed that the realized investments and the produced new attractions have only a slight role in attracting the target audience. Still the traditionally popular attractions attract most of the visitors to Debrecen therefore the most important task for the leaders of the Debrecen-Hortobágy Tourism Destination Management founded in 2010 is to propagate the new attraction elements.

  8. Using a network modularity analysis to inform management of a rare endemic plant in the northern Great Plains, USA

    Science.gov (United States)

    Larson, Diane L.; Droege, Sam; Rabie, Paul A.; Larson, Jennifer L.; Devalez, Jelle; Haar, Milton; McDermott-Kubeczko, Margaret

    2014-01-01

    1. Analyses of flower-visitor interaction networks allow application of community-level information to conservation problems, but management recommendations that ensue from such analyses are not well characterized. Results of modularity analyses, which detect groups of species (modules) that interact more with each other than with species outside their module, may be particularly applicable to management concerns. 2. We conducted modularity analyses of networks surrounding a rare endemic annual plant, Eriogonum visheri, at Badlands National Park, USA, in 2010 and 2011. Plant species visited were determined by pollen on insect bodies and by flower species upon which insects were captured. Roles within modules (network hub, module hub, connector and peripheral, in decreasing order of network structural importance) were determined for each species. 3. Relationships demonstrated by the modularity analysis, in concert with knowledge of pollen species carried by insects, allowed us to infer effects of two invasive species on E. visheri. Sharing a module increased risk of interspecific pollen transfer to E. visheri. Control of invasive Salsola tragus, which shared a module with E. visheri, is therefore a prudent management objective, but lack of control of invasive Melilotus officinalis, which occupied a different module, is unlikely to negatively affect pollination of E. visheri. Eriogonum pauciflorum may occupy a key position in this network, supporting insects from the E. visheri module when E. visheri is less abundant. 4. Year-to-year variation in species' roles suggests management decisions must be based on observations over several years. Information on pollen deposition on stigmas would greatly strengthen inferences made from the modularity analysis. 5. Synthesis and applications: Assessing the consequences of pollination, whether at the community or individual level, is inherently time-consuming. A trade-off exists: rather than an estimate of fitness effects, the

  9. Preliminary study of uranium in Pennsylvanian and lower Permian strata in the Powder River Basin, Wyoming and Montana, and the Northern Great Plains

    International Nuclear Information System (INIS)

    Dunagan, J.F. Jr.; Kadish, K.A.

    1977-11-01

    Persistent and widespread radiometric anomalies occur in Pennsylvanian and Lower Permian strata in the subsurface of the northern Great Plains and the Powder River Basin. The primary host lithology of these anomalies is shale interbedded with sandstone, dolomite, and dolomitic sandstone. Samples from the project area indicate that uranium is responsible for some anomalies. In some samples there seems to be a correlation between high uranium content and high organic-carbon content, which possibly indicates that carbonaceous material acted as a trapping mechanism in some strata. The Pennsylvanian and Permian rocks studied are predominantly marine carbonates and clastics, but there are rocks of fluvial origin in the basal Pennsylvanian of Montana, North Dakota, and South Dakota and in the Pennsylvanian and Permian deposits on the east flank of the Laramie Mountains. Fine-grained clastic rocks that flank the Chadron arch in western Nebraska are possibly of continental origin. The trend of the Chadron arch approximately parallels the trend of radiometric anomalies in the subsurface Permian-Pennsylvanian section. Possible source areas for uranium in the sediments studied were pre-Pennsylvanian strata of the Canadian Shield and Precambrian igneous rocks of the Ancestral Rocky Mountains

  10. The Use of Remote Sensing for Monitoring, Prediction, and Management of Hydrologic, Agricultural, and Ecological Processes in the Northern Great Plains

    Science.gov (United States)

    Farwell, Sherry O.; DeTroye, Diane (Technical Monitor)

    2002-01-01

    The NASA-EPSCoR program in South Dakota is focused on the enhancement of NASA-related research in earth system science and corresponding infrastructure development to support this theme. Hence, the program has adopted a strategy that keys on research projects that: a) establish quantitative links between geospatial information technologies and fundamental climatic and ecosystem processes in the Northern Great Plains (NGP) and b) develop and use coupled modeling tools, which can be initialized by data from combined satellite and surface measurements, to provide reliable predictions and management guidance for hydrologic, agricultural, and ecological systems of the NGP. Building a partnership network that includes both internal and external team members is recognized as an essential element of the SD NASA-EPSCoR program. Hence, promoting and tracking such linkages along with their relevant programmatic consequences are used as one metric to assess the program's progress and success. This annual report first summarizes general activities and accomplishments, and then provides progress narratives for the two separate, yet related research projects that are essential components of the SD NASA-EPSCoR program.

  11. The timing and nature of Late Quaternary vegetation changes in the northern Great Plains, USA and Canada: a re-assessment of the spruce phase

    Science.gov (United States)

    Yansa, Catherine H.

    2006-02-01

    This paper revises the chronology for the northward migration of Picea glauca (white spruce) across the northern Great Plains, following the recession of the Laurentide Ice Sheet, and reinterprets the species composition and structure of the late-glacial vegetation on the basis of pollen and plant-macrofossil analysis. The timing of spruce migration is based on 26 14C ages obtained from Picea macrofossils. The date for the appearance of white spruce in southern South Dakota, USA, remains unchanged, 12,600 14C yr BP (ca 15,000 cal yr BP), but its arrival in southern Saskatchewan, Canada, by 10,300 14C yr BP (ca 12,100 cal yr BP) is about 1500 years later than previously estimated based on an organic sediment date. Picea glauca thus migrated northwards at an average rate of 0.38 km/ 14C year (0.30 km/calendar year), significantly slower than the previously published rate of 2 km/ 14C year. White spruce trees probably inhabited lake shorelines, whereas prairie, parkland, and boreal plants occupied both lowlands and uplands, forming an open white spruce parkland. This interpretation differs from a previous reconstruction of a boreal-type spruce forest and thus offers another paleoclimatic interpretation. Precipitation was probably low and summer temperatures relatively mild, averaging about 19 °C.

  12. Estimation of potential evapotranspiration from extraterrestrial radiation, air temperature and humidity to assess future climate change effects on the vegetation of the Northern Great Plains, USA

    Science.gov (United States)

    King, David A.; Bachelet, Dominique M.; Symstad, Amy J.; Ferschweiler, Ken; Hobbins, Michael

    2014-01-01

    The potential evapotranspiration (PET) that would occur with unlimited plant access to water is a central driver of simulated plant growth in many ecological models. PET is influenced by solar and longwave radiation, temperature, wind speed, and humidity, but it is often modeled as a function of temperature alone. This approach can cause biases in projections of future climate impacts in part because it confounds the effects of warming due to increased greenhouse gases with that which would be caused by increased radiation from the sun. We developed an algorithm for linking PET to extraterrestrial solar radiation (incoming top-of atmosphere solar radiation), as well as temperature and atmospheric water vapor pressure, and incorporated this algorithm into the dynamic global vegetation model MC1. We tested the new algorithm for the Northern Great Plains, USA, whose remaining grasslands are threatened by continuing woody encroachment. Both the new and the standard temperature-dependent MC1 algorithm adequately simulated current PET, as compared to the more rigorous PenPan model of Rotstayn et al. (2006). However, compared to the standard algorithm, the new algorithm projected a much more gradual increase in PET over the 21st century for three contrasting future climates. This difference led to lower simulated drought effects and hence greater woody encroachment with the new algorithm, illustrating the importance of more rigorous calculations of PET in ecological models dealing with climate change.

  13. Non-European Union doctors in the National Health Service: why, when and how do they come to the United Kingdom of Great Britain and Northern Ireland?

    Directory of Open Access Journals (Sweden)

    Jude Edward B

    2007-02-01

    Full Text Available Abstract Background As many as 30% of doctors working for the National Health System (NHS of the United Kingdom of Great Britain and Northern Ireland (UK have obtained their primary qualifications from a country outside the European Union. However, factors driving this migration of doctors to the UK merit continuing exploration. Our objective was to obtain training and employment profile of UK doctors who obtained their primary medical qualification outside the European Union (non-European doctors and to assess self-reported reasons for their migration. Methods We conducted an online survey of non-European doctors using a pre-validated questionnaire. Results One thousand six hundred and nineteen doctors of 26 different nationalities completed the survey. Of the respondents, 90.1% were from India and over three-quarters migrated to the UK mainly for 'training'. Other reasons cited were 'better pay' (7.2%, 'better work environment' (7.1% and 'having family and friends in the UK' (2.8%. Many of the respondents have been in the UK for more than a year (88.8%, with 31.3% having spent more than 3 years gaining experience of working in the NHS. Most respondents believe they will be affected by recent changes to UK immigration policy (86.6%, few report that they would be unaffected (3.7% and the rest are unsure (9.8%. Conclusion The primary reason for many non-European doctors to migrate to the UK is for training within the NHS. Secondary reasons like better pay, better work environment and having friends and family in the UK also play a role in attracting these doctors, predominantly from the Indian subcontinent and other British Commonwealth countries.

  14. Spatial variation in pollen and charcoal records in relation to the 665 yr BP Kaharoa tephra at Harataonga Bay, Great Barrier Island, northern New Zealand : preliminary results

    International Nuclear Information System (INIS)

    Horrocks, M.; Nichol, S.L.; Jones, M.D.; Shane, P.A.; Sutton, D.G.

    2001-01-01

    We present preliminary results of a pollen study examining spatial variability using the 665 14 C yr BP Kaharoa tephra as the key stratigraphic marker. Our aim is to highlight potential differences in pollen and charcoal profiles from adjacent sites, and to point out the implications of these differences for the interpretation of pollen records. Three sediment cores were taken from swampy ground behind foredunes at Harataonga Bay, a small catchment on Great Barrier Island. Core 1 provides a c. 5000 14 C yr record of the swamp and is typical of northern New Zealand pollen profiles in that the deforestation signal appears immediately after Kaharoa tephra. Cores 2 and 3, however, show this signal at least 1 m below the tephra layer. Also, artefact pollen of gourd Lagenaria, an introduced Polynesian cultigen, was found 80 cm below the tephra layer in Core 2. This apparent difference in the timing of the human signal may be explained by the occurrence of small-scale, highly localised fires that are not recorded at adjacent sites. This has implications for inferring date of human presence in extensive areas, such as regions or large catchments, from a small number of pollen cores taken from within those areas. An alternative explanation is that sediments in cores 2 and 3 have been reworked to a much greater extent than those in Core 1. This has implications for the use of tephra as critical data for events, particularly when using recent tephra such as Kaharoa for dating human presence when the necessary resolution is to decades or centuries rather than millenia. (author). 18 refs., 6 figs., 2 tabs

  15. Communication dated 30 May 2007 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA concerning enrichment bonds - A voluntary scheme for reliable access to nuclear fuel

    International Nuclear Information System (INIS)

    2007-01-01

    The Secretariat has received a letter dated 30 May 2007 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA attaching a UK Non-paper entitled 'Food for Thought: Enrichment Bonds - A Voluntary Scheme for Reliable Access to Nuclear Fuel'. As requested in that letter, the letter and the attachment is now being circulated for the information of all Member States

  16. Communication dated 19 May 2011 received from the Resident Representative of the United Kingdom of Great Britain and Northern Ireland to the Agency regarding Assurance of Supply of Enrichment Services and Low Enriched Uranium for Use in Nuclear Power Plants

    International Nuclear Information System (INIS)

    2011-01-01

    The Secretariat has received a letter dated 19 May 2011 from the Resident Representative of the United Kingdom of Great Britain and Northern Ireland to the Agency, attaching the Proposal for the Assurance of Supply of Enrichment Services and Low Enriched Uranium for Use in Nuclear Power Plants, as described in document GOV/2011/10. As requested by the Resident Representative, the letter and its attachment are circulated herewith for information of all Member States

  17. The Text of the Agreement of 6 September 1976 between The United Kingdom of Great Britain and Northern Ireland, The European Atomic Energy Community and the Agency in Connection with the Treaty on the Non-Proliferation of Nuclear Weapons

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1978-10-15

    The text of the Agreement, and of the Protocol which is an integral part thereof, between the United Kingdom of Great Britain and Northern Ireland, the European Atomic Energy Community and the Agency for the application of safeguards in the United Kingdom in connection with the Treaty on the Non-Proliferation of Nuclear Weapons is reproduced in this document for the information of all Members.

  18. Communication dated 19 May 2011 received from the Resident Representative of the United Kingdom of Great Britain and Northern Ireland to the Agency regarding Assurance of Supply of Enrichment Services and Low Enriched Uranium for Use in Nuclear Power Plants

    International Nuclear Information System (INIS)

    2011-01-01

    The Secretariat has received a letter dated 19 May 2011 from the Resident Representative of the United Kingdom of Great Britain and Northern Ireland to the Agency, attaching the Proposal for the Assurance of Supply of Enrichment Services and Low Enriched Uranium for Use in Nuclear Power Plants, as described in document GOV/2011/10. As requested by the Resident Representative, the letter and its attachment are circulated herewith for information of all Member States [es

  19. The Text of the Agreement of 6 September 1976 between The United Kingdom of Great Britain and Northern Ireland, The European Atomic Energy Community and the Agency in Connection with the Treaty on the Non-Proliferation of Nuclear Weapons

    International Nuclear Information System (INIS)

    1978-10-01

    The text of the Agreement, and of the Protocol which is an integral part thereof, between the United Kingdom of Great Britain and Northern Ireland, the European Atomic Energy Community and the Agency for the application of safeguards in the United Kingdom in connection with the Treaty on the Non-Proliferation of Nuclear Weapons is reproduced in this document for the information of all Members

  20. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2010-01-01

    The Secretariat has received a note verbale dated 28 July 2010 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines'), and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2009 [es

  1. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2011-01-01

    The Secretariat has received a note verbale dated 6 June 2011 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2010 [es

  2. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2013-01-01

    The Secretariat has received a note verbale dated 17 June 2013 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2012 [es

  3. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning Its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2007-01-01

    The Secretariat has received a Note Verbale dated 23 August 2007 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the United Nations and the International Organizations in Vienna in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2006 [es

  4. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2012-01-01

    The Secretariat has received a note verbale dated 3 July 2012 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2011 [es

  5. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2009-01-01

    The Secretariat has received a note verbale dated 26 June 2009 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2008 [es

  6. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning Its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2006-01-01

    The Director General has received a Note Verbale dated 3 August 2005 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2004

  7. Communication received from the United Kingdom of Great Britain and Northern Ireland concerning its policies regarding the management of plutonium. Statements on the management of plutonium and of highly enriched uranium

    International Nuclear Information System (INIS)

    2004-01-01

    The Director General has received a Note Verbale dated 2 August 2004 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2003

  8. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning Its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2007-01-01

    The Secretariat has received a Note Verbale dated 23 August 2007 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the United Nations and the International Organizations in Vienna in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2006 [fr

  9. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2012-01-01

    The Secretariat has received a note verbale dated 3 July 2012 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2011 [fr

  10. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2013-01-01

    The Secretariat has received a note verbale dated 17 June 2013 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2012 [fr

  11. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2012-01-01

    The Secretariat has received a note verbale dated 3 July 2012 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2011

  12. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning Its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2007-01-01

    The Secretariat has received a Note Verbale dated 23 August 2007 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the United Nations and the International Organizations in Vienna in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2006

  13. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2011-01-01

    The Secretariat has received a note verbale dated 6 June 2011 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2010

  14. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2013-01-01

    The Secretariat has received a note verbale dated 17 June 2013 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2012

  15. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2010-01-01

    The Secretariat has received a note verbale dated 28 July 2010 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines'), and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2009

  16. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2009-01-01

    The Secretariat has received a note verbale dated 26 June 2009 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2008

  17. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2011-01-01

    The Secretariat has received a note verbale dated 6 June 2011 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2010 [fr

  18. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2010-01-01

    The Secretariat has received a note verbale dated 28 July 2010 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines'), and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2009 [fr

  19. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium

    International Nuclear Information System (INIS)

    2009-01-01

    The Secretariat has received a note verbale dated 26 June 2009 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2008 [fr

  20. Effect on stone lines on soil chemical characteristics under continuous sorghum cropping in semiarid Burkina Faso

    NARCIS (Netherlands)

    Zougmore, R.; Gnankambary, Z.; Guillobez, L.S.; Stroosnijder, L.

    2002-01-01

    In the semiarid Sahel, farmers commonly lay stone lines in fields to disperse runoff. This study was conducted in northern Burkina Faso to assess the chemical fertility of soil under a permanent, non-fertilised sorghum crop, which is the main production system in this area, 5 years after laying

  1. Impacts of water development on aquatic macroinvertebrates, amphibians, and plants in wetlands of a semi-arid landscape

    Science.gov (United States)

    Euliss, Ned H.; Mushet, David M.

    2004-01-01

    We compared the macroinvertebrate and amphibian communities of 12 excavated and 12 natural wetlands in western North Dakota, USA, to assess the effects of artificially lengthened hydroperiods on the biotic communities of wetlands in this semi-arid region. Excavated wetlands were much deeper and captured greater volumes of water than natural wetlands. Most excavated wetlands maintained water throughout the study period (May to October 1999), whereas most of the natural wetlands were dry by June. Excavated wetlands were largely unvegetated or contained submergent and deep-marsh plant species. The natural wetlands had two well-defined vegetative zones populated by plant species typical of wet meadows and shallow marshes. Excavated wetlands had a richer aquatic macroinvertebrate community that included several predatory taxa not found in natural wetlands. Taxa adapted to the short hydroperiods of seasonal wetlands were largely absent from excavated wetlands. The amphibian community of natural and excavated wetlands included the boreal chorus frog (Pseudacris maculata), northern leopard frog (Rana pipiens), plains spadefoot (Scaphiopus bombifrons), Woodhouse's toad (Bufo woodhousii woodhousii), and tiger salamander (Ambystoma tigrinum). The plains spadefoot occurred only in natural wetlands while tiger salamanders occurred in all 12 excavated wetlands and only one natural wetland. Boreal chorus frogs and northern leopard frogs were present in both wetland types; however, they successfully reproduced only in wetlands lacking tiger salamanders. Artificially extending the hydroperiod of wetlands by excavation has greatly influenced the composition of native biotic communities adapted to the naturally short hydroperiods of wetlands in this semi-arid region. The compositional change of the biotic communities can be related to hydrological changes and biotic interactions, especially predation related to excavation.

  2. Influence of a large late summer precipitation event on food limitation and grasshopper population dynamics in a northern Great Plains grassland.

    Science.gov (United States)

    Branson, David H

    2008-06-01

    The complex interplay between grasshoppers, weather conditions, and plants that cause fluctuations in grasshopper populations remains poorly understood, and little is known about the ecological processes that generate grasshopper outbreaks. Grasshopper populations respond to interacting extrinsic and intrinsic factors, with yearly and decadal weather patterns and the timing of precipitation all potentially important. The effects of initial and increasing grasshopper densities on grasshopper survival and reproductive correlates were examined at a northern mixed-grass prairie site through manipulations of grasshopper densities inside 10-m2 cages. High-quality grass growth occurred after a 9.1-cm mid-August rain. Reduced proportional survival was apparent in the two higher density treatments before the rain, indicative of food-limited density-dependent mortality. However, the large late summer rainfall event mediated the effects of exploitative competition on demographic characteristics because of the high-quality vegetation growth. This led to weaker effects of food limitation on survival and reproduction at the end of the experiment. The results indicate a direct link between weather variation, resource quality and grasshopper population dynamics led to a severe grasshopper outbreak and show that infrequent large precipitation events can have significant effects on population dynamics. Additional research is needed to examine the importance of infrequent large precipitation events on grasshopper population dynamics in grassland ecosystems.

  3. Tree ring δ18O reveals no long-term change of atmospheric water demand since 1800 in the northern Great Hinggan Mountains, China

    Science.gov (United States)

    Liu, Xiaohong; Zhang, Xuanwen; Zhao, Liangju; Xu, Guobao; Wang, Lixin; Sun, Weizhen; Zhang, Qiuliang; Wang, Wenzhi; Zeng, Xiaomin; Wu, Guoju

    2017-07-01

    Global warming will significantly increase transpirational water demand, which could dramatically affect plant physiology and carbon and water budgets. Tree ring δ18O is a potential index of the leaf-to-air vapor-pressure deficit (VPD) and therefore has great potential for long-term climatic reconstruction. Here we developed δ18O chronologies of two dominant native trees, Dahurian larch (Larix gmelinii Rupr.) and Mongolian pine (Pinus sylvestris var. mongolica), from a permafrost region in the Great Hinggan Mountains of northeastern China. We found that the July-August VPD and relative humidity were the dominant factors that controlled tree ring δ18O in the study region, indicating strong regulation of stomatal conductance. Based on the larch and pine tree ring δ18O chronologies, we developed a reliable summer (July-August) VPD reconstruction since 1800. Warming growing season temperatures increase transpiration and enrich cellulose 18O, but precipitation seemed to be the most important influence on VPD changes in this cold region. Periods with stronger transpirational demand occurred around the 1850s, from 1914 to 1925, and from 2005 to 2010. However, we found no overall long-term increasing or decreasing trends for VPD since 1800, suggesting that despite the increasing temperatures and thawing permafrost throughout the region, forest transpirational demand has not increased significantly during the past two centuries. Under current climatic conditions, VPD did not limit growth of larch and pine, even during extremely drought years. Our findings will support more realistic evaluations and reliable predictions of the potential influences of ongoing climatic change on carbon and water cycles and on forest dynamics in permafrost regions.

  4. Seven new species of Paleanotus (Annelida: Chrysopetalidae) described from Lizard Island, Great Barrier Reef, and coral reefs of northern Australia and the Indo-Pacific: two cryptic species pairs revealed between western Pacific Ocean and the eastern Indian Ocean.

    Science.gov (United States)

    Watson, Charlotte

    2015-09-18

    Morphological investigation into the paleate genus Paleanotus Schmarda 1861 of the family Chrysopetalidae from northern Australian coral reefs, primarily Lizard Island and outlying reefs, included a complex of very small, slender individuals (length < 5 mm). This complex resolved into 7 new species, described herein: Paleanotus inornatus n. sp., P. adornatus n. sp., P. chrysos n. sp., P. aquifolia n. sp., P. latifolia n. sp., P. silus n. sp., and P. silopsis n. sp. A key is provided to the new species and Paleanotus distinguished from Treptopale and Hyalopale, two closely related genera. Diagnostic features of the apical structure and shape of the notochaetal main paleae plus median paleae shape and raised rib pattern, differentiates each species from the other. Gametous states are described. Two cryptic species pairs (Paleanotus silopsis n. sp. and P. silus n. sp.; Paleanotus aquifolia n. sp. and P. latifolia n. sp.) were identified. In each case one species is restricted to either the NE or NW Australian coast. In each pair the most eastern point for the NW Australian species range occurs at Darwin, western Arnhemland, Northern Territory. Additional material for each species pair extends their respective ranges northwards: NW Australia to Thailand, Andaman Sea, eastern Indian Ocean or NE Australia, Great Barrier Reef to the Philippines, western Pacific Ocean. Cryptic morphology and potential genetic diversity is discussed in Paleanotus inornatus n. sp. and P. adornatus n. sp. that possess overlapping widespread distribution patterns across northern Australia and Indo-Pacific reefs. The smallest bodied taxon, Paleanotus chrysos n. sp. is the only species with a Coral Sea range encompassing Lizard Island, Heron Island and New Caledonia.

  5. Soil Respiration in Semiarid Temperate Grasslands under Various Land Management.

    Directory of Open Access Journals (Sweden)

    Zhen Wang

    Full Text Available Soil respiration, a major component of the global carbon cycle, is significantly influenced by land management practices. Grasslands are potentially a major sink for carbon, but can also be a source. Here, we investigated the potential effect of land management (grazing, clipping, and ungrazed enclosures on soil respiration in the semiarid grassland of northern China. Our results showed the mean soil respiration was significantly higher under enclosures (2.17 μmol.m(-2.s(-1 and clipping (2.06 μmol.m(-2.s(-1 than under grazing (1.65 μmol.m-(2.s(-1 over the three growing seasons. The high rates of soil respiration under enclosure and clipping were associated with the higher belowground net primary productivity (BNPP. Our analyses indicated that soil respiration was primarily related to BNPP under grazing, to soil water content under clipping. Using structural equation models, we found that soil water content, aboveground net primary productivity (ANPP and BNPP regulated soil respiration, with soil water content as the predominant factor. Our findings highlight that management-induced changes in abiotic (soil temperature and soil water content and biotic (ANPP and BNPP factors regulate soil respiration in the semiarid temperate grassland of northern China.

  6. Soil Respiration in Semiarid Temperate Grasslands under Various Land Management.

    Science.gov (United States)

    Wang, Zhen; Ji, Lei; Hou, Xiangyang; Schellenberg, Michael P

    2016-01-01

    Soil respiration, a major component of the global carbon cycle, is significantly influenced by land management practices. Grasslands are potentially a major sink for carbon, but can also be a source. Here, we investigated the potential effect of land management (grazing, clipping, and ungrazed enclosures) on soil respiration in the semiarid grassland of northern China. Our results showed the mean soil respiration was significantly higher under enclosures (2.17 μmol.m(-2).s(-1)) and clipping (2.06 μmol.m(-2).s(-1)) than under grazing (1.65 μmol.m-(2).s(-1)) over the three growing seasons. The high rates of soil respiration under enclosure and clipping were associated with the higher belowground net primary productivity (BNPP). Our analyses indicated that soil respiration was primarily related to BNPP under grazing, to soil water content under clipping. Using structural equation models, we found that soil water content, aboveground net primary productivity (ANPP) and BNPP regulated soil respiration, with soil water content as the predominant factor. Our findings highlight that management-induced changes in abiotic (soil temperature and soil water content) and biotic (ANPP and BNPP) factors regulate soil respiration in the semiarid temperate grassland of northern China.

  7. The impact of unconfined mine tailings in residential areas from a mining town in a semi-arid environment: Nacozari, Sonora, Mexico.

    Science.gov (United States)

    Meza-Figueroa, Diana; Maier, Raina M; de la O-Villanueva, Margarita; Gómez-Alvarez, Agustín; Moreno-Zazueta, Alan; Rivera, Jacinto; Campillo, Alberto; Grandlic, Christopher J; Anaya, Ricardo; Palafox-Reyes, Juan

    2009-09-01

    Past mining activities in northern Mexico left a legacy of delerict landscapes devoid of vegetation and seasonal formation of salt efflorescence. Metal content was measured in mine tailings, efflorescent salts, soils, road dust, and residential soils to investigate contamination. Climatic effects such as heavy wind and rainfall events can have great impact on the dispersion of metals in semi-arid areas, since soils are typically sparsely vegetated. Geochemical analysis of this site revealed that even though total metal content in mine tailings was relatively low (e.g. Cu= 1000 mg kg(-1)), metals including Mn, Ba, Zn, and Cu were all found at significantly higher levels in efflorescence salts formed by evaporation on the tailings impoundment surface following the rainy season (e.g. Cu= 68,000 mg kg(-1)). Such efflorescent fine-grained salts are susceptible to wind erosion resulting in increased metal spread to nearby residential soils. Our results highlight the importance of seasonally dependent salt-formation and wind erosion in determining risk levels associated with potential inhalation or ingestion of airborne particulates originating from contaminated sites such as tailings impoundments. In low metal-content mine tailings located in arid and semi-arid environments, efflorescence salts could represent a human health risk and a challenge for plant establishment in mine tailings.

  8. Tropical Warm Semi-Arid Regions Expanding Over Temperate Latitudes In The Projected 21st Century

    Science.gov (United States)

    Rajaud, A.; de Noblet, N. I.

    2015-12-01

    Two billion people today live in drylands, where extreme climatic conditions prevail, and natural resources are limited. Drylands are expected to expand under several scenarios of climatic change. However, relevant adaptation strategies need to account for the aridity level: it conditions the equilibrium tree-cover density, ranging from deserts (hyper-arid) to dense savannas (sub-humid). Here we focus on the evolution of climatically defined warm semi-arid areas, where low-tree density covers can be maintained. We study the global repartition of these regions in the future and the bioclimatic shifts involved. We adopted a bioclimatological approach based on the Köppen climate classification. The warm semi-arid class is characterized by mean annual temperatures over 18°C and a rainfall-limitation criterion. A multi-model ensemble of CMIP5 projections for three representative concentration pathways was selected to analyze future conditions. The classification was first applied to the start, middle and end of the 20th and 21st centuries, in order to localize past and future warm semi-arid regions. Then, time-series for the classification were built to characterize trends and variability in the evolution of those regions. According to the CRU datasets, global expansion of the warm semi-arid area has already started (~+13%), following the global warming trend since the 1900s. This will continue according to all projections, most significantly so outside the tropical belt. Under the "business as usual" scenario, the global warm semi-arid area will increase by 30% and expand 12° poleward in the Northern Hemisphere, according to the multi-model mean. Drying drives the conversion from equatorial sub-humid conditions. Beyond 30° of latitude, cold semi-arid conditions become warm semi-arid through warming, and temperate conditions through combined warming and drying processes. Those various transitions may have drastic but also very distinct ecological and sociological

  9. Testing for thresholds in a semiarid grassland: The influence of prairie dogs and plague

    Science.gov (United States)

    State and transition models for semiarid grasslands in the Great Plains of North America suggest that the presence of herbivorous black-tailed prairie dogs (Cynomys ludovicianus) on a site (1) creates a vegetation state characterized by increased dominance of annual forbs and unpalatable bunchgrasse...

  10. Great Apes

    Science.gov (United States)

    Sleeman, Jonathan M.; Cerveny, Shannon

    2014-01-01

    Anesthesia of great apes is often necessary to conduct diagnostic analysis, provide therapeutics, facilitate surgical procedures, and enable transport and translocation for conservation purposes. Due to the stress of remote delivery injection of anesthetic agents, recent studies have focused on oral delivery and/or transmucosal absorption of preanesthetic and anesthetic agents. Maintenance of the airway and provision of oxygen is an important aspect of anesthesia in great ape species. The provision of analgesia is an important aspect of the anesthesia protocol for any procedure involving painful stimuli. Opioids and nonsteroidal anti-inflammatory drugs (NSAIDs) are often administered alone, or in combination to provide multi-modal analgesia. There is increasing conservation management of in situ great ape populations, which has resulted in the development of field anesthesia techniques for free-living great apes for the purposes of translocation, reintroduction into the wild, and clinical interventions.

  11. Communication received from the United Kingdom of Great Britain and Northern Ireland concerning its policies regarding the management of plutonium. Statements on the management of plutonium and of highly enriched uranium

    International Nuclear Information System (INIS)

    2003-01-01

    The Director General has received a Note Verbale, dated 17 July 2003, from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government of the United Kingdom, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines'), and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its national holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2002. The Government of the United Kingdom has also made available a statement of its annual figures for holdings of civil high enriched uranium (HEU), and of civil depleted, natural and low enriched uranium (DNLEU) in the civil nuclear fuel cycle, as of 31 December 2002. 3. In the light of the requests expressed by the Government of the United Kingdom in its Note Verbale of 1 December 1997 concerning its policies regarding the management of plutonium (INFCIRC/549 of 16 March 1998) and in its Note Verbale of 17 July 2003, the Note Verbale of 17 July 2003 and the enclosures thereto are attached for the information of all Member States

  12. State Transitions in Semiarid Landscapes

    Science.gov (United States)

    Phillips, J. D.

    2012-04-01

    The U.S. Department of Agriculture has developed a large number of state-and-transition models (STM) to predict and interpret changes in vegetation communities in drylands of the southwestern U.S. These are represented as box-and-arrow models indicating potential changes in response to various combinations of management practices and environmental forcings. Analysis of the 320 STMs developed for areas within the state of Texas reveals two important aspects of environmental change in semiarid environments. First, the STMs are highly local—they are specific to very particular combinations of landform, soil, and climate. This is consistent with the perfect landscape concept in geomorphology, which emphasizes the irreducible importance of geographically and historically contingent local factors in addition to universal laws or principles in determining the state or condition of landscapes. Second, analysis of the STMs using algebraic graph theory shows that a majority of them have structures that tend to amplify effects of change and disturbances. In many cases the STMs represent a form of self-organization characterized by the potential of divergent behavior rather than convergence toward a dominant pattern or outcome. These results indicate that geomorphic, hydrologic, and ecological responses to climate and land use change are likely to be highly variable and idiosyncratic, both within and between semiarid landscapes of Texas.

  13. 27 June 2012 - Ambassador K. Pierce, Permanent Representative of the United Kingdom of Great Britain and Northern Ireland to the United Nations Office and other international organisations in Geneva visiting the LHC tunnel at Point 5 with Department Head P. Collier and CMS control room with Former Collaboration Spokesperson J. Virdee.

    CERN Multimedia

    Laurent Egli

    2012-01-01

    27 June 2012 - Ambassador K. Pierce, Permanent Representative of the United Kingdom of Great Britain and Northern Ireland to the United Nations Office and other international organisations in Geneva visiting the LHC tunnel at Point 5 with Department Head P. Collier and CMS control room with Former Collaboration Spokesperson J. Virdee.

  14. 9 April 2013 - Minister for Universities and Science United Kingdom of Great Britain and Northern Ireland D. Willetts in the ATLAS experimental cavern with ATLAS Collaboration Spokesperson D. Charlton and in the LHC tunnel at Point 1 with Beams Department Head P. Collier. Director for Accelerators and Technology S. Myers, Editor at the Communication Group K. Kahle and Beams Department Engineer R. Veness present.

    CERN Multimedia

    Jean-Claude Gadmer

    2013-01-01

    9 April 2013 - Minister for Universities and Science United Kingdom of Great Britain and Northern Ireland D. Willetts in the ATLAS experimental cavern with ATLAS Collaboration Spokesperson D. Charlton and in the LHC tunnel at Point 1 with Beams Department Head P. Collier. Director for Accelerators and Technology S. Myers, Editor at the Communication Group K. Kahle and Beams Department Engineer R. Veness present.

  15. Soil Moisture Variability and its Effects on Herbage Production in Semi-arid Rangelands of Kenya

    International Nuclear Information System (INIS)

    Too, D.K.; Trlica, M.J.; Swift, D.M.; Musembi, D.K.

    1999-01-01

    Results obtained from recent studies focused on rangelands potential as influenced by human activity and climatic factors in the semi-arid and arid pastoral ecosystems of Northern Kenya indicated great temporal and spatial forage production variability. The objective of the studies was to document primary production in relation to water stress (drought), herbivory and direct human activities. Efforts also focused on finding possibilities of increasing productivity while conserving the finite resources for sustainable use. Laboratory, field and numerical methods were employed over several seasons and years. Forb and grass production was more variable than that of the browse (dwarf shrub) layer. Compared to forbs and dwarf shrubs, the grass layer contributed less to the total production in all seasons, indicating that the region had less potential for grazers compared to browsers. Spatial-temporal variation in rangeland carrying capacity reflected the great spatial heterogeneity in vegetation types and production. Similarly, seasonal differences were very evident, with highest estimates in the long rainy and the lowest during the dry and short rainy seasons, respectively. Factors limiting rangeland production potential were identified to be moisture deficiency, resource-use conflicts, an increasing and partially sedentarised nomadic population, overgrazing, tree felling, and land degradation (desert encroachment). Measures that can improve rangeland production potential and provide a better way of life for the inhabitants of the region include: (a) identification of land degradation (e.g. by means of bio-indicators and Geographical Information Systems, GIS); (b) technical interventions (i.e. soil and water conservation, restoration of degraded areas, fodder production); (c) social-economic interventions (i.e. resolution of resource-use conflicts, alleviation of poverty, infrastructure development improvement of livestock marketing channels etc.) and (d) continued

  16. Drought Variability and Land Degradation in Semiarid Regions: Assessment Using Remote Sensing Data and Drought Indices (1982–2011

    Directory of Open Access Journals (Sweden)

    Sergio M. Vicente-Serrano

    2015-04-01

    Full Text Available We analyzed potential land degradation processes in semiarid regions worldwide using long time series of remote sensing images and the Normalized Difference Vegetation Index (NDVI for the period 1981 to 2011. The objectives of the study were to identify semiarid regions showing a marked decrease in potential vegetation activity, indicative of the occurrence of land degradation processes, and to assess the possible influence of the observed drought trends quantified using the Standardized Precipitation Evapotranspiration Index (SPEI. We found that the NDVI values recorded during the period of maximum vegetation activity (NDVImax predominantly showed a positive evolution in the majority of the semiarid regions assessed, but NDVImax was highly correlated with drought variability, and the trends of drought events influenced trends in NDVImax at the global scale. The semiarid regions that showed most increase in NDVImax (the Sahel, northern Australia, South Africa were characterized by a clear positive trend in the SPEI values, indicative of conditions of greater humidity and lesser drought conditions. While changes in drought severity may be an important driver of NDVI trends and land degradation processes in semiarid regions worldwide, drought did not apparently explain some of the observed changes in NDVImax. This reflects the complexity of vegetation activity processes in the world’s semiarid regions, and the difficulty of defining a universal response to drought in these regions, where a number of factors (natural and anthropogenic may also affect on land degradation.

  17. Drought Variability and Land Degradation in Semiarid Regions: Assessment Using Remote Sensing Data and Drought Indices (1982–2011)

    KAUST Repository

    Vicente-Serrano, Sergio

    2015-04-14

    We analyzed potential land degradation processes in semiarid regions worldwide using long time series of remote sensing images and the Normalized Difference Vegetation Index (NDVI) for the period 1981 to 2011. The objectives of the study were to identify semiarid regions showing a marked decrease in potential vegetation activity, indicative of the occurrence of land degradation processes, and to assess the possible influence of the observed drought trends quantified using the Standardized Precipitation Evapotranspiration Index (SPEI). We found that the NDVI values recorded during the period of maximum vegetation activity (NDVImax) predominantly showed a positive evolution in the majority of the semiarid regions assessed, but NDVImax was highly correlated with drought variability, and the trends of drought events influenced trends in NDVImax at the global scale. The semiarid regions that showed most increase in NDVImax (the Sahel, northern Australia, South Africa) were characterized by a clear positive trend in the SPEI values, indicative of conditions of greater humidity and lesser drought conditions. While changes in drought severity may be an important driver of NDVI trends and land degradation processes in semiarid regions worldwide, drought did not apparently explain some of the observed changes in NDVImax. This reflects the complexity of vegetation activity processes in the world’s semiarid regions, and the difficulty of defining a universal response to drought in these regions, where a number of factors (natural and anthropogenic) may also affect on land degradation.

  18. Drought Variability and Land Degradation in Semiarid Regions: Assessment Using Remote Sensing Data and Drought Indices (1982–2011)

    KAUST Repository

    Vicente-Serrano, Sergio; Cabello, Daniel; Tomá s-Burguera, Miquel; Martí n-Herná ndez, Natalia; Beguerí a, Santiago; Azorin-Molina, Cesar; Kenawy, Ahmed

    2015-01-01

    We analyzed potential land degradation processes in semiarid regions worldwide using long time series of remote sensing images and the Normalized Difference Vegetation Index (NDVI) for the period 1981 to 2011. The objectives of the study were to identify semiarid regions showing a marked decrease in potential vegetation activity, indicative of the occurrence of land degradation processes, and to assess the possible influence of the observed drought trends quantified using the Standardized Precipitation Evapotranspiration Index (SPEI). We found that the NDVI values recorded during the period of maximum vegetation activity (NDVImax) predominantly showed a positive evolution in the majority of the semiarid regions assessed, but NDVImax was highly correlated with drought variability, and the trends of drought events influenced trends in NDVImax at the global scale. The semiarid regions that showed most increase in NDVImax (the Sahel, northern Australia, South Africa) were characterized by a clear positive trend in the SPEI values, indicative of conditions of greater humidity and lesser drought conditions. While changes in drought severity may be an important driver of NDVI trends and land degradation processes in semiarid regions worldwide, drought did not apparently explain some of the observed changes in NDVImax. This reflects the complexity of vegetation activity processes in the world’s semiarid regions, and the difficulty of defining a universal response to drought in these regions, where a number of factors (natural and anthropogenic) may also affect on land degradation.

  19. Great Expectations

    NARCIS (Netherlands)

    Dickens, Charles

    2005-01-01

    One of Dickens's most renowned and enjoyable novels, Great Expectations tells the story of Pip, an orphan boy who wishes to transcend his humble origins and finds himself unexpectedly given the opportunity to live a life of wealth and respectability. Over the course of the tale, in which Pip

  20. Great Lakes

    Science.gov (United States)

    Edsall, Thomas A.; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.

    1998-01-01

    The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean.The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a).The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human

  1. Assessing Ecosystem Model Performance in Semiarid Systems

    Science.gov (United States)

    Thomas, A.; Dietze, M.; Scott, R. L.; Biederman, J. A.

    2017-12-01

    In ecosystem process modelling, comparing outputs to benchmark datasets observed in the field is an important way to validate models, allowing the modelling community to track model performance over time and compare models at specific sites. Multi-model comparison projects as well as models themselves have largely been focused on temperate forests and similar biomes. Semiarid regions, on the other hand, are underrepresented in land surface and ecosystem modelling efforts, and yet will be disproportionately impacted by disturbances such as climate change due to their sensitivity to changes in the water balance. Benchmarking models at semiarid sites is an important step in assessing and improving models' suitability for predicting the impact of disturbance on semiarid ecosystems. In this study, several ecosystem models were compared at a semiarid grassland in southwestern Arizona using PEcAn, or the Predictive Ecosystem Analyzer, an open-source eco-informatics toolbox ideal for creating the repeatable model workflows necessary for benchmarking. Models included SIPNET, DALEC, JULES, ED2, GDAY, LPJ-GUESS, MAESPA, CLM, CABLE, and FATES. Comparison between model output and benchmarks such as net ecosystem exchange (NEE) tended to produce high root mean square error and low correlation coefficients, reflecting poor simulation of seasonality and the tendency for models to create much higher carbon sources than observed. These results indicate that ecosystem models do not currently adequately represent semiarid ecosystem processes.

  2. Spatial distribution of overland flow and sediment yield in semi-arid rangelands

    International Nuclear Information System (INIS)

    Sarah, P.; Lavee, H.

    2009-01-01

    Feedbacks and mutual links exist among soil, vegetation and water; they enable co-evolution of these features within eco-geomorphic systems, These relations are fragile, especially in semi-arid areas where grazing is the main land use. The simples subdivision of the surface of many semi-arid rangelands is into a two-component mosaic pattern comprising shrub patches interspersed with open spaces, with the former acting s skinks for water and other resources, and the latter as sources. However close observations in areas under grazing in the northern Negev region of Israel suggested that the spatial patterns of surface components is more complicated, and that the open space between shrubs consists of two components: herbaceous areas, separated by trampling routes that support no vegetation. (Author)

  3. Water conservation in semiarid dryland agriculture

    International Nuclear Information System (INIS)

    Willis, W.O.

    1980-01-01

    Factors affecting water conservation in semiarid dryland regions are discussed. Because precipitation is the only source of water for plant growth in most semiarid regions, a good understanding of precipitation patterns (quantity, distribution, and their probable frequency) is needed for each dryland area. The various dryland practices, e.g. tillage, cultivars, residue management, fertility, erosion control, and grazing, must be considered as integral parts of an entire system to develop best management practices and to gain most efficient water conservation for food and fiber production. (author)

  4. Geomorphic controls on Great Basin riparian vegetation at the watershed and process zone scales

    Science.gov (United States)

    Blake Meneken Engelhardt

    2009-01-01

    Riparian ecosystems supply valuable resources in all landscapes, but especially in semiarid regions such as the Great Basin of the western United States. Over half of Great Basin streams are thought to be in poor ecological condition and further deterioration is of significant concern to stakeholders. A thorough understanding of how physical processes acting at...

  5. Is annual recharge coefficient a valid concept in arid and semi-arid regions?

    Directory of Open Access Journals (Sweden)

    Y. Cheng

    2017-10-01

    Full Text Available Deep soil recharge (DSR (at depth greater than 200 cm is an important part of water circulation in arid and semi-arid regions. Quantitative monitoring of DSR is of great importance to assess water resources and to study water balance in arid and semi-arid regions. This study used a typical bare land on the eastern margin of Mu Us Sandy Land in the Ordos Basin of China as an example to illustrate a new lysimeter method of measuring DSR to examine if the annual recharge coefficient is valid or not in the study site, where the annual recharge efficient is the ratio of annual DSR over annual total precipitation. Positioning monitoring was done on precipitation and DSR measurements underneath mobile sand dunes from 2013 to 2015 in the study area. Results showed that use of an annual recharge coefficient for estimating DSR in bare sand land in arid and semi-arid regions is questionable and could lead to considerable errors. It appeared that DSR in those regions was influenced by precipitation pattern and was closely correlated with spontaneous strong precipitation events (with precipitation greater than 10 mm other than the total precipitation. This study showed that as much as 42 % of precipitation in a single strong precipitation event can be transformed into DSR. During the observation period, the maximum annual DSR could make up 24.33 % of the annual precipitation. This study provided a reliable method of estimating DSR in sandy areas of arid and semi-arid regions, which is valuable for managing groundwater resources and ecological restoration in those regions. It also provided strong evidence that the annual recharge coefficient was invalid for calculating DSR in arid and semi-arid regions. This study shows that DSR is closely related to the strong precipitation events, rather than to the average annual precipitation, as well as the precipitation patterns.

  6. Spatial patterns and natural recruitment of native shrubs in a semi-arid sandy land.

    Science.gov (United States)

    Wu, Bo; Yang, Hongxiao

    2013-01-01

    Passive restoration depending on native shrubs is an attractive approach for restoring desertified landscapes in semi-arid sandy regions. We sought to understand the relationships between spatial patterns of native shrubs and their survival ability in sandy environments. Furthermore, we applied our results to better understand whether passive restoration is feasible for desertified landscapes in semi-arid sandy regions. The study was conducted in the semi-arid Mu Us sandy land of northern China with the native shrub Artemisia ordosica. We analyzed population structures and patterns of A. ordosica at the edges and centers of land patches where sand was stabilized by A. ordosica-dominated vegetation. Saplings were more aggregated than adults, and both were more aggregated at the patch edges than at the patch centers. At the patch edges, spatial association of the saplings with the adults was mostly positive at distances 0.3-6.6 m, and turned from positive to neutral, and even negative, at other distances. At the patch centers, the saplings were spaced almost randomly around the adults, and their distances from the adults did not seem to affect their locations. A greater number of A. ordosica individuals emerged at the patch edges than at the patch centers. Such patterns may have resulted from their integrative adjustment to specific conditions of soil water supply and sand drift intensity. These findings suggest that in semi-arid sandy regions, native shrubs that are well-adapted to local environments may serve as low-cost and competent ecological engineers that can promote the passive restoration of surrounding patches of mobile sandy land.

  7. Estimation of alluvial recharge in the semiarid

    OpenAIRE

    Andrade,Tafnes S.; Montenegro,Suzana M. G. L.; Montenegro,Abelardo A. de A.; Rodrigues,Diogo F. B.

    2014-01-01

    In areas where there is irrigated agriculture, the recuperation of water reserves in alluvial aquifers may occur preferentially due to precipitation. Recharging can be evaluated from variation information of water depth measured in piezometers or observation wells. Thus, the aim of this research is to study the recharge in the alluvial aquifer formed by the Mimoso temporary stream in the semiarid region of Pernambuco (PE), Brazil, using the method of the fluctuation of the water level. This s...

  8. Water conservation for semi-arid rangelands

    International Nuclear Information System (INIS)

    Willis, W.O.

    1983-01-01

    Water deficiency is most often the cause for low forage production on rangelands in semi-arid and arid regions. Water conservation methods have been developed but additional research is needed to develop the best management practices for various climatic regions. Poor management is another major cause of low rangeland production. Better management, including the application of research findings, depends on attitudes, policies, adaptability of findings, resources for implementation and a good understanding of the governing biotic and abiotic factors. (author)

  9. The Great Recession was not so Great

    NARCIS (Netherlands)

    van Ours, J.C.

    2015-01-01

    The Great Recession is characterized by a GDP-decline that was unprecedented in the past decades. This paper discusses the implications of the Great Recession analyzing labor market data from 20 OECD countries. Comparing the Great Recession with the 1980s recession it is concluded that there is a

  10. A review of fire effects on vegetation and soils in the Great Basin region: response and ecological site characteristics

    Science.gov (United States)

    Miller, Richard F.; Chambers, Jeanne C.; Pyke, David A.; Pierson, Fred B.; Williams, C. Jason

    2013-01-01

    This review synthesizes the state of knowledge on fire effects on vegetation and soils in semi-arid ecosystems in the Great Basin Region, including the central and northern Great Basin and Range, Columbia River Basin, and the Snake River Plain. We summarize available literature related to: (1) the effects of environmental gradients, ecological site, and vegetation characteristics on resilience to disturbance and resistance to invasive species; (2) the effects of fire on individual plant species and communities, biological soil crusts, seed banks, soil nutrients, and hydrology; and (3) the role of fire severity, fire versus fire surrogate treatments, and post-fire grazing in determining ecosystem response. From this, we identify knowledge gaps and present a framework for predicting plant successional trajectories following wild and prescribed fires and fire surrogate treatments. Possibly the three most important ecological site characteristics that influence a site’s resilience (ability of the ecological site to recover from disturbance) and resistance to invasive species are soil temperature/moisture regimes and the composition and structure of vegetation on the ecological site just prior to the disturbance event.

  11. Aeolian desertification and its control in Northern China

    Directory of Open Access Journals (Sweden)

    Wang Tao

    2014-12-01

    Full Text Available Aeolian desertification is a kind of land degradation through wind erosion resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in Northern China. To compare the results of remote sensing data in the late 1950s, 1975, 1987, 2000 and 2010, we can summarize that the expansion of aeolian desertified land in Northern China has been accelerated for 5 decades, as its annual expanded rate was 1,560 km2 during the late 1950s and 1975, 2,100 km2 between 1975 and 1988, 3,600 km2 from 1988 to 2000, and -1,375 km2 from 2000 to 2010. The desertified land kept expanding before 2000 and began to get rehabilitated since 2000. The impact of human activity on the aeolian desertification process is much more active than that from natural process which mainly incarnates on land use change (from rangeland to farmland and increased land use intensity (over-cultivation, over-grassing, and over-fuelwood collection. The natural vegetation cover destroyed by the human activities has accelerated the development of aeolian desertification. China has made great progresses in understanding and combating aeolian desertification through decades of effort and there were many projects carried out for the prevention and control purpose. The National Project of Grain for Green Program is the most important one with 1060 counties of 22 provinces involved. The objective is to withdraw 3.67 million ha of dry land farming and degraded steppe, and 5.13 million ha of aeolian desertified land suited to reforestation and re-vegetation will be rehabilitated. There are about 8 million ha of lands suffering from aeolian desertification will be brought under control in the next ten years and 26.67 million ha of windbreaks will be planted. The total investment from the central government is estimated to be 75 billion RMB (11 billion USD.

  12. Northern employment

    International Nuclear Information System (INIS)

    Zavitz, J.

    1997-01-01

    Hiring practices and policies and employment opportunities that were available in the Beaufort Sea and MacKenzie Delta project for local residents and for people from southern Canada were dealt with in this chapter. Depending on the source, Northern hiring was a mere token, or a genuine and successful effort on the part of the companies to involve the native population and to share with them the benefits of the project. The fact remains that opening up job opportunities for Northerners was not easily attained, and would never have been realized without the involvement of government and community organizations. Government also played a major role in developing policies and training regimes. By the end of exploration operations, the hiring of Northern residents in the oil and gas industry had become a requirement of drilling applications. Training programs were also created to ensure that Northern residents received the means necessary to take advantage of Northern employment opportunities

  13. Hypogeous fungi from Southern Spanish semi-arid lands

    NARCIS (Netherlands)

    Honrubia, M.; Cano, A.; Molina-Niñirola, C.

    1992-01-01

    Six hypogeous fungi of Ascomycotina and Basidiomycotina have been studied from semiarid zones in Southern Spain. Melanogaster variegatus (Vitt.) Tul. is recorded for the first time from Spain. Picoa juniperi Vitt. and Terfezia claveryi Chat. are revealed as the most frequent species in semi-arid

  14. Pathways to Resilience in Semi-Arid Economies (PRISE)

    International Development Research Centre (IDRC) Digital Library (Canada)

    rlarbey

    PRISE Goal. This research will support the emergence of equitable, climate resilient economic development in semi-arid lands through research excellence and ... change in semi-arid areas, and how is the private sector adapting? 4. How do ... Role. Individual. Contact email. Lead Principal Investigator. Dr Tom Mitchell.

  15. Identifying plant traits: a key aspect for suitable species selection in ecological restoration of semiarid slopes

    Science.gov (United States)

    Bochet, Esther; García-Fayos, Patricio

    2017-04-01

    conclusion, these new insights from basic ecology and practical management guidance represent a great opportunity for practitioners to move forward with the success of roadslope restoration in semiarid environments.

  16. Feedback mechanisms between water availability and water use in a semi-arid river basin: a geographically explicit multi-agent simulation approach

    NARCIS (Netherlands)

    van Oel, P.R.; Krol, Martinus S.; Hoekstra, Arjen Ysbert; Taddei, Renzo R.

    2010-01-01

    Understanding the processes responsible for the distribution of water availability over space and time is of great importance to spatial planning in a semi-arid river basin. In this study the usefulness of a multi-agent simulation (MAS) approach for representing these processes is discussed. A MAS

  17. Priority research and management issues for the imperiled Great Basin of the western United States

    Science.gov (United States)

    Jeanne C. Chambers; Michael J. Wisdom

    2009-01-01

    Like many arid and semiarid regions, the Great Basin of the western United States is undergoing major ecological, social, and economic changes that are having widespread detrimental effects on the structure, composition, and function of native ecosystems. The causes of change are highly interactive and include urban, suburban, and exurban growth, past and present land...

  18. Cover crop biomass production and water use in the central great plains under varying water availability

    Science.gov (United States)

    The water-limited environment of the semi-arid central Great Plains may not have potential to produce enough cover crop biomass to generate benefits associated with cover crop use in more humid regions. There have been reports that cover crops grown in mixtures produce more biomass with greater wate...

  19. Great Lakes Science Center

    Data.gov (United States)

    Federal Laboratory Consortium — Since 1927, Great Lakes Science Center (GLSC) research has provided critical information for the sound management of Great Lakes fish populations and other important...

  20. Cereals for the semi-arid tropics

    International Nuclear Information System (INIS)

    De Wet, J.M.J.

    1989-01-01

    The region of semi-arid tropics is the most famine prone area of the world. This region with nearly one billion people extends across some 20 million square kilometres. Major domesticated cereals adapted to semi-arid regions are sorghum (Sorghum bicolor (L.) Moench), foxtail millet (Setaria italica (L.) P. Beauv.) and pearl millet (Pennisetum glaucum (L.) R. Br.). Several minor cereals are grown as speciality crops, or harvested in the wild in times of severe drought and scarcity. Important in the African Sahel are the fonios Digitaria iburua Stapf, D. exilis (Kapist) Stapf and Brachiaria deflexa (Schumach). C.E. Hubbard. These species are aggressive colonizers and are commonly encouraged as weeds in cultivated fields. Sown genotypes differ from their close wild relatives primarily in the lack of efficient natural seed dispersal. The fonios lend themselves to rapid domestication. Several wild cereals extend well beyond the limits of agriculture into the Sahara. Commonly harvested are the perennial Stipagrostis pungens and Panicum turgidum, and the annual Cenchrus biflorus (kram-kram). Kram-kram yields well under extreme heat and drought stress, and holds promise as a domesticated cereal. Sauwi millet (Panicum sonorum) is promising cereal in arid northwestern Mexico. (author). 31 refs

  1. An overview of the floristic richness and conservation of the arid regions of northern Mexico

    Science.gov (United States)

    Laura Arriaga; Elizabeth Moreno; Claudia Aguilar

    2005-01-01

    The arid and semiarid regions of Northern Mexico harbor diverse, highly endemic, and geographically complex ecosystems. These share topographic and biogeographic similarities that can be used as an analytical framework to assess biodiversity patterns. This study presents the current status of vascular plant inventories for Mexican Aridamerica. The spatial distribution...

  2. HCMM: Soil moisture in relation to geologic structure and lithology, northern California. [Northern Coast Range, Sacramento Valley, and the Modoc Plateau

    Science.gov (United States)

    Rich, E. I. (Principal Investigator)

    1981-01-01

    Heat capacity mapping mission images of about 80,000 sq km in northern California were qualitatively evaluated for usefulness in regional geologic investigations of structure and lithology. The thermal characteristics recorded vary among the several geomorphic provinces and depend chiefly on the topographic expression and vegetation cover. Identification of rock types, or groups of rock types, was most successfully carried out within the semiarid parts of the region; however, extensive features, such as faults, folds and volcanic fields could be delineated. Comparisons of seasonally obtained HCMM images are of limited value except in semiarid regions.

  3. AGROECOLOGY AND CLIMATE CHANGE IN THE SEMIARID TROPICS

    Directory of Open Access Journals (Sweden)

    Guillermo Gamarra-Rojas

    2017-04-01

    Full Text Available This article makes a theoretical and, to a certain extent, propositional reflection on the conceptions, assumptions and evidences of climate change in the tropics, with emphasis on the Brazilian semiarid region. The contributions of agriculture to climate change are presented and the impacts of climate change on family agriculture in the semiarid region are analyzed. Evidence of mitigation and adaptation in agroecological systems of the semiarid region is presented and an outline of an agenda of the sector based on the commitments assumed by the country and the needs of mitigation and adaptation is provided.

  4. Economic Feasibility of Underwater Adduction of Rivers for Metropolises in Semiarid Coastal Environments: Case Studies

    Directory of Open Access Journals (Sweden)

    Daniel Albiero

    2018-02-01

    Full Text Available The supply of raw water to the inhabitants of metropolises is not a trivial problem, and involves many challenges, both in terms of the quantity and quality of this water. When these metropolises are located in semiarid regions, this challenge takes on enormous proportions, and in many situations, there are no sustainable solutions, especially in times of global climate change. One hypothesis to try to mitigate this problem in coastal cities is the underwater adduction of rivers. The objective of this paper was to make the abstraction of drinking water in the mouths of great rivers near semi-arid regions. This water would be led by a pipeline below the water level and would follow the route of the seacoast, where the energy to move the water would be supplied by an axial hydraulic pump embedded in the pipeline by water-cooled electric motors driven by the energy generated from offshore wind turbines. Estimates have been made for the four metropolises in semi-arid regions: Fortaleza-Brazil, Dalian-China, Tel Aviv-Israel, and Gaza-Palestine, where it was possible to calculate economic viability through the Present Worth Value, the internal rate of return, and payback. The results indicated that Fortaleza had economic viability under restrictions. Dalian proved the ideal result. Tel Aviv and Gaza both had great economic viability, but only if Egypt agreed to supply water from the Nile. This paper proved that the management of the water supply for human consumption through the underwater adduction of rivers could be achieved with real clearance for any deficits in the volume of water that due to global climate change are becoming more frequent.

  5. Envisioning Adaptive Strategies to Change: Participatory Scenarios for Agropastoral Semiarid Systems in Nicaragua

    Directory of Open Access Journals (Sweden)

    Federica Ravera

    2011-03-01

    Full Text Available Historically, the semiarid social-ecological systems of the dry Central American corridor have proven resilient to pressures. However, in the last century, these systems have experienced huge environmental and socioeconomic changes that have increased the vulnerability of local livelihoods to shocks. New approaches are needed to capture complex, uncertain, cross-scale and nonlinear relationships among drivers of change and vulnerability. Therefore, to tackle this challenge, we have applied a participatory and interdisciplinary methodological framework of vulnerability assessment to a case study in northern Nicaragua. We triangulated a range of information and data from participatory and scientific research to explore historical and current drivers of changes that affect the system's components and indicators of vulnerability, represented in a 3-dimensional space in terms of ecological resilience, the socioeconomic ability of individuals to adapt to change, and an institutional capacity to buffer and respond to crisis. A projection of climatic changes combined with a participatory scenario analysis helped, then, to heuristically analyze tendencies of vulnerability in the future and to explore what policy options might enhance the system's adaptive capacity to face new pressures. Our work primarily contributes to an empirical understanding of key factors that influence vulnerability and learning about local strategies to adapt to change in semiarid agropastoral systems in Central America. We also make a methodological contribution by testing the use of a multidimensional vulnerability framework as a way of stimulating discussion among researchers, local stakeholders, and policy makers.

  6. Mucorales from the semiarid of Pernambuco, Brazil.

    Science.gov (United States)

    de Azevedo Santiago, André Luiz Cabral Monteiro; Dos Santos, Paulo Jorge Parreira; Maia, Leonor Costa

    2013-01-01

    Nineteen taxa of Mucorales, belonging to Absidia, Apophysomyces, Cunninghamella, Fennellomyces, Lichtheimia, Mucor, Mycotypha, Rhizopus and Syncephalastrum were isolated from 36 composite soil samples in three semiarid areas in the State of Pernambuco (Triunfo, Cabrobó and Belém de São Francisco), Northeast Brazil, which are characterized by Caatinga vegetation. Triunfo is preserved, whereas Cabroró and Belém de São Francisco are experiencing low and severe desertification processes, respectively. Mucorales were isolated in Petri dishes in triplicate from 5 mg samples of soil placed on the surface of wheat germ agar plus chloramphenicol and Cercobin [Dimethyl 4,49-(103 phenylene) bis (3-thioallophanate)] medium. The plates were left on a bench at room temperature (28 ± 2 °C) for 72 h of alternating dark and light periods. Absidia cylindrospora presented the highest amount of CFU/g of soil, followed by L. hyalospora, C. phaeospora and C. echinulata var. echinulata. The latter, and R. microsporus var. microsporus, presented the highest frequencies of occurrence. Soils from Triunfo showed higher diversity of Mucorales than the samples from the other areas, although without differing statistically in relation to species richness. The communities of Mucorales from the degraded areas were more similar, while that from the preserved area was quite different. Most of the identified specimens have been commonly isolated from soil in other Brazilian regions, which indicates that they are not endemic of the semiarid. Eleven taxa are registered for the first time in this ecosystem, while F. heterothallicus is reported for the first time in Brazil.

  7. Mucorales from the semiarid of Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    André Luiz Cabral Monteiro de Azevedo Santiago

    2013-01-01

    Full Text Available Nineteen taxa of Mucorales, belonging to Absidi, Apophysomyces, Cunninghamella, Fennellomyces, Lichtheimi, Mucor, Mycotypha, Rhizopus and Syncephalastrum were isolated from 36 composite soil samples in three semiarid areas in the State of Pernambuco (Triunfo, Cabrobó and Belém de São Francisco, Northeast Brazil, which are characterized by Caatinga vegetation. Triunfo is preserved, whereas Cabroró and Belém de São Francisco are experiencing low and severe desertification processes, respectively. Mucorales were isolated in Petri dishes in triplicate from 5 mg samples of soil placed on the surface of wheat germ agar plus chloramphenicol and Cercobin [Dimethyl 4,49-(103 phenylene bis (3-thioallophanate] medium. The plates were left on a bench at room temperature (28 ± 2 ºC for 72 h of alternating dark and light periods. Absidia cylindrospora presented the highest amount of CFU/g of soil, followed by L. hyalospor, C. phaeospora and C. echinulata var. echinulata. The latter, and R. microsporus var. microsporus, presented the highest frequencies of occurrence. Soils from Triunfo showed higher diversity of Mucorales than the samples from the other areas, although without differing statistically in relation to species richness. The communities of Mucorales from the degraded areas were more similar, while that from the preserved area was quite different. Most of the identified specimens have been commonly isolated from soil in other Brazilian regions, which indicates that they are not endemic of the semiarid. Eleven taxa are registered for the first time in this ecosystem, while F. heterothallicus is reported for the first time in Brazil.

  8. Introducing Pathways to Resilience in Semi-Arid Economies (PRISE ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    rlarbey

    Equitable, climate resilient economic development in semi-arid .... manufacturing or services (apart from health, insurance and tourism). Further research ... evaluated, particularly economic impact assessments of adaptation both on existing.

  9. Patchiness in semi-arid dwarf shrublands: evidence from satellite ...

    African Journals Online (AJOL)

    ... Plants; Remote sensing; Rhigozum obovatum Burch; Satellite-derived vegetation indices; Woody species; patchiness; semi-arid; dwarf shrubland; shrublands; co2; assimilation; karoo; south africa; ndvi; satellite imagery; geochemical mound; rhigozum obovatum; eriocephalus ericoides; pentzia incana; vegetation; botany

  10. Mining influence on underground water resources in arid and semiarid regions

    Science.gov (United States)

    Luo, A. K.; Hou, Y.; Hu, X. Y.

    2018-02-01

    Coordinated mining of coal and water resources in arid and semiarid regions has traditionally become a focus issue. The research takes Energy and Chemical Base in Northern Shaanxi as an example, and conducts statistical analysis on coal yield and drainage volume from several large-scale mines in the mining area. Meanwhile, research determines average water volume per ton coal, and calculates four typical years’ drainage volume in different mining intensity. Then during mining drainage, with the combination of precipitation observation data in recent two decades and water level data from observation well, the calculation of groundwater table, precipitation infiltration recharge, and evaporation capacity are performed. Moreover, the research analyzes the transforming relationship between surface water, mine water, and groundwater. The result shows that the main reason for reduction of water resources quantity and transforming relationship between surface water, groundwater, and mine water is massive mine drainage, which is caused by large-scale coal mining in the research area.

  11. HCMM: Soil moisture in relation to geologic structure and lithology, northern California

    Science.gov (United States)

    Rich, E. I. (Principal Investigator)

    1981-01-01

    Some HCMM images of about 80,000 sq km in northern California were qualitatively evaluated for usefulness in regional geologic investigations of structure and lithology. The thermal characteristics recorded vary among the several geomorphic provinces and depends chiefly on the topographic expression and vegetation cover. Identification of rock types, or groups of rock types, was most successfully carried out within the semi-arid parts of the region; however, extensive features, such as faults, folds and volcanic fields could be delineated. Comparisons of seasonally obtained HCMM images were limited value, except in semi-arid regions.

  12. An Overview of Biodegradation of LNAPLs in Coastal (Semi)-arid Environment.

    KAUST Repository

    Yadav, Brijesh Kumar

    2011-02-22

    Contamination of soil and water due to the release of light non-aqueous phase liquids (LNAPLs) is a ubiquitous problem. The problem is more severe in arid and semi-arid coastal regions where most of the petroleum production and related refinery industries are located. Biological treatment of these organic contaminated resources is receiving increasing interests and where applicable, can serve as a cost-effective remediation alternative. The success of bioremediation greatly depends on the prevailing environmental variables, and their remediation favoring customization requires a sound understanding of their integrated behavior on fate and transport of LNAPLs under site-specific conditions. The arid and semi-arid coastal sites are characterized by specific environmental extremes; primarily, varying low and high temperatures, high salinity, water table dynamics, and fluctuating soil moisture content. An understanding of the behavior of these environmental variables on biological interactions with LNAPLs would be helpful in customizing the bioremediation for restoring problematic sites in these regions. Therefore, this paper reviews the microbial degradation of LNAPLs in soil-water, considering the influences of prevailing environmental parameters of arid and semi-arid coastal regions. First, the mechanism of biodegradation of LNAPLs is discussed briefly, followed by a summary of popular kinetic models used by researchers for describing the degradation rate of these hydrocarbons. Next, the impact of soil moisture content, water table dynamics, and soil-water temperature on the fate and transport of LNAPLs are discussed, including an overview of the studies conducted so far. Finally, based on the reviewed information, a general conclusion is presented with recommendations for future research subjects on optimizing the bioremediation technique in the field under the aforesaid environmental conditions. The present review will be useful to better understand the

  13. Sedimentology, geochemistry and OSL dating of the alluvial succession in the northern Gujarat alluvial plain (western India) - A record to evaluate the sensitivity of a semiarid fluvial system to the climatic and tectonic forcing since the late Marine Isotopic Stage 3

    Science.gov (United States)

    Bhattacharya, Falguni; Shukla, Anil D.; Patel, R. C.; Rastogi, B. K.; Juyal, Navin

    2017-11-01

    The alluvial successions in the northern Gujarat alluvial plain (western India) have been investigated for reconstructing the climatic fluctuations during the last 40 ka. Alluvial architecture and geochemical proxies indicate prevalence of a strengthened Indian Summer Monsoon (ISM) with fluctuations between the late Marine Isotopic Stage 3 (MIS 3; 37 ka) to the early MIS 2 (27 ka). A gradual onset of aridity (declining ISM) after 27 ka with peak aridity at 22 ka is observed. A gradual strengthening of ISM at around 18 and > 12 ka followed by a short reversal in ISM intensity between 12 and 11 ka, is attributed to the Younger-Dryas (YD) cooling event. The aeolian sand sheet dated to 6 and 3.5 ka represents the onset of regional aridity. Following this, a short-lived humid phase was observed after 2 ka, which includes the Medieval Warm Period (MWP). The study suggests that the variability in the ISM to the latitudinal migration of the Inter Tropical Convergence Zone was caused by insolation-driven cooling and warming events in the North Atlantic. The incision of the valley fill alluvium occurred in two distinct phases. The older incision phase occurred after 11 ka and before 6 ka, whereas the younger incision phase that led to the development of present day topography is bracketed between 3.5 ka and before 1 ka. The older incision phase is ascribed to the early to mid-Holocene enhanced ISM (climatically driven), whereas the younger incision seems to be modulated by the activation of basement faults (tectonically driven).

  14. INFLUENCE OF SEMIARID SUMMER BROWSING ON CHEMICAL

    Directory of Open Access Journals (Sweden)

    Claudia Puga

    2009-06-01

    Full Text Available A group (A of 20 female French Alpine goats (50 ± 5 Kg BW were fed on summer semiarid vegetation in Querétaro, México. Other group (B with similar characteristic was fed in full confinement with Lucerne hay and concentrate of cereals. Four kids of cheese were prepared: 1 browsed-raw (BR, 2 browsed-pasteurized (BP, 3 indoor-raw (IR and 4 indoor-pasteurized (IP; using 30 kg of milk per group, 15 kg each group were proceed in raw and 15 kg each were pasteurized. Moisture, energy, protein, ash, lipids, cholesterol, fatty acids profile and CLA were determined in the cheeses; the results were analyzed with a variance analysis in a 2x2 factorial arrangement. Energy, fat and ash did not affect for feeding system and heat treatment. Protein content was higher in IP cheese compared with BR and BP cheeses. BR cheese had a lowest cholesterol value in relation to BP, IR and IP cheeses. The browed cheeses had the highest concentration of CLA, EPA and DHA acids in relation to indoor cheeses. Pasteurization did not have effect in cheese quality. Browsing increased concentration of compounds with a beneficial effect on human health, factor that could add revenue to the small farmer’s income.

  15. Salinization mechanisms in semi-arid regions

    International Nuclear Information System (INIS)

    Santiago, M.M.F.

    1984-01-01

    During a period of three years the basins of the Pereira de Miranda and Caxitore dams, located in the crystalline rock area of Ceara, Brazil, were studied in order to determine the mechanisms of salinization of their waters. Isotope methods ( 18 O/ 16 O) and hidrochemistry (determination of the of the maior ions) were applied to surface, underground and rain water in this study. An isotope model was designed and applied to the determination of evaporation and percolation of dams in semi-arid zones during the dry season. The results are compared to those from a conventional chemical model. As causes of salinization of the water in the dams, the contributions of the rain itself and the lixiviation of the soil are quantified. An interaction between the dams and the underground water is imperceptible. The salinization of the underground water is attributed to recharge of the aquifer with rain water from the surface runoff followed by evaporation of the water rising, due to capilarity, in a one-directional flow to the surface. (Author) [pt

  16. Range Cattle Winter Water Consumption in Northern Great Plains

    Science.gov (United States)

    Water consumption and DMI has been found to be positively correlated and may interact to alter range cow productivity. Environmental conditions can have a significant influence on water consumption during the winter. The objective of this study was to determine influences of water and air temperatur...

  17. Great Lakes Literacy Principles

    Science.gov (United States)

    Fortner, Rosanne W.; Manzo, Lyndsey

    2011-03-01

    Lakes Superior, Huron, Michigan, Ontario, and Erie together form North America's Great Lakes, a region that contains 20% of the world's fresh surface water and is home to roughly one quarter of the U.S. population (Figure 1). Supporting a $4 billion sport fishing industry, plus $16 billion annually in boating, 1.5 million U.S. jobs, and $62 billion in annual wages directly, the Great Lakes form the backbone of a regional economy that is vital to the United States as a whole (see http://www.miseagrant.umich.edu/downloads/economy/11-708-Great-Lakes-Jobs.pdf). Yet the grandeur and importance of this freshwater resource are little understood, not only by people in the rest of the country but also by many in the region itself. To help address this lack of knowledge, the Centers for Ocean Sciences Education Excellence (COSEE) Great Lakes, supported by the U.S. National Science Foundation and the National Oceanic and Atmospheric Administration, developed literacy principles for the Great Lakes to serve as a guide for education of students and the public. These “Great Lakes Literacy Principles” represent an understanding of the Great Lakes' influences on society and society's influences on the Great Lakes.

  18. The Next Great Generation?

    Science.gov (United States)

    Brownstein, Andrew

    2000-01-01

    Discusses ideas from a new book, "Millennials Rising: The Next Great Generation," (by Neil Howe and William Strauss) suggesting that youth culture is on the cusp of a radical shift with the generation beginning with this year's college freshmen who are typically team oriented, optimistic, and poised for greatness on a global scale. Includes a…

  19. Water Resources Management. Coexistence and Conflict in Semiarid Brazil

    Directory of Open Access Journals (Sweden)

    Thiago Ferreira Dias

    2016-01-01

    Full Text Available The paper analyzes water management in the Brazilian semiarid region with emphasis on aspects of coexistence and conflicts over access in rural areas. Experiences of social coexistence in semiarid technologies from the joint to the Brazilian semiarid (ASA and water conflicts from cases of irrigated areas in the states of Ceará and Rio Grande do Norte are explained. For this purpose, we used a qualitative approach through the use of primary and secondary data. The cases provide concrete actions that articulate civil society and the State in favor of the common good. The results indicate that the policy articulated by the ASA there is a governance process in which there are links between the forums of civil society and the interfaces in the planning and implementation of public policies in building public agenda that can bridge the gap between planning, deployment, management and improvement of this policy. In the second case the policy is implemented exclusion and allocation of those communities, placing them on the margins of development, scrapping its links with the territory. The water is not seen from the perspective of the common good and the communities are perceived as an obstacle to “development”. Finally, it outlines themselves from the cases under study, with the idea that limiting access to water in the semiarid region, reflects the precarious welfare and perpetuation of relations of dependency, paternalism and clientelism high proportion of the population rural Brazilian semiarid.

  20. Reduction of tree cover in West African woodlands and promotion in semi-arid farmlands

    Science.gov (United States)

    Brandt, Martin; Rasmussen, Kjeld; Hiernaux, Pierre; Herrmann, Stefanie; Tucker, Compton J.; Tong, Xiaoye; Tian, Feng; Mertz, Ole; Kergoat, Laurent; Mbow, Cheikh; David, John L.; Melocik, Katherine A.; Dendoncker, Morgane; Vincke, Caroline; Fensholt, Rasmus

    2018-05-01

    Woody vegetation in farmland acts as a carbon sink and provides ecosystem services for local people, but no macroscale assessments of the impact of management and climate on woody cover exist for drylands. Here we make use of very high spatial resolution satellite imagery to derive wall-to-wall woody cover patterns in tropical West African drylands. Our study reveals that mean woody cover in farmlands along all semi-arid and sub-humid rainfall zones is 16%, on average only 6% lower than in savannahs. In semi-arid Sahel, farmland management promotes woody cover around villages (11%), while neighbouring savannahs had on average less woody cover. However, farmlands in sub-humid zones have a greatly reduced woody cover (21%) as compared with savannahs (33%). In the region as a whole, rainfall, terrain and soil are the most important (80%) determinants of woody cover, while management factors play a smaller (20%) role. We conclude that agricultural expansion causes a considerable reduction of trees in woodlands, but observations in Sahel indicate that villagers safeguard trees on nearby farmlands which contradicts simplistic ideas of a high negative correlation between population density and woody cover.

  1. Global synthesis of groundwater recharge in semiarid and arid regions

    Science.gov (United States)

    Scanlon, Bridget R.; Keese, K.E.; Flint, A.L.; Flint, L.E.; Gaye, C.B.; Edmunds, W.M.; Simmers, I.

    2006-01-01

    Global synthesis of the findings from ∼140 recharge study areas in semiarid and arid regions provides important information on recharge rates, controls, and processes, which are critical for sustainable water development. Water resource evaluation, dryland salinity assessment (Australia), and radioactive waste disposal (US) are among the primary goals of many of these recharge studies. The chloride mass balance (CMB) technique is widely used to estimate recharge. Average recharge rates estimated over large areas (40–374 000 km2) range from 0·2 to 35 mm year−1, representing 0·1–5% of long-term average annual precipitation. Extreme local variability in recharge, with rates up to ∼720 m year−1, results from focussed recharge beneath ephemeral streams and lakes and preferential flow mostly in fractured systems. System response to climate variability and land use/land cover (LU/LC) changes is archived in unsaturated zone tracer profiles and in groundwater level fluctuations. Inter-annual climate variability related to El Niño Southern Oscillation (ENSO) results in up to three times higher recharge in regions within the SW US during periods of frequent El Niños (1977–1998) relative to periods dominated by La Niñas (1941–1957). Enhanced recharge related to ENSO is also documented in Argentina. Climate variability at decadal to century scales recorded in chloride profiles in Africa results in recharge rates of 30 mm year−1 during the Sahel drought (1970–1986) to 150 mm year−1 during non-drought periods. Variations in climate at millennial scales in the SW US changed systems from recharge during the Pleistocene glacial period (≥10 000 years ago) to discharge during the Holocene semiarid period. LU/LC changes such as deforestation in Australia increased recharge up to about 2 orders of magnitude. Changes from natural grassland and shrublands to dryland (rain-fed) agriculture altered systems from discharge (evapotranspiration, ET) to recharge in

  2. Great Indoors Awards 2007

    Index Scriptorium Estoniae

    2007-01-01

    Hollandis Maastrichtis jagati 17. XI esimest korda rahvusvahelist auhinda The Great Indoors Award. Aasta sisekujundusfirmaks valiti Masamichi Katayama asutatud Wonderwall. Auhinna said veel Zaha Hadid, Heatherwick Studio, Ryui Nakamura Architects ja Item Idem

  3. Great Lakes Bathymetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lakes Michigan, Erie, Saint Clair, Ontario and Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and...

  4. Modeling mechanisms of vegetation change due to fire in a semi-arid ecosystem

    Science.gov (United States)

    White, J.D.; Gutzwiller, K.J.; Barrow, W.C.; Randall, L.J.; Swint, P.

    2008-01-01

    Vegetation growth and community composition in semi-arid environments is determined by water availability and carbon assimilation mechanisms specific to different plant types. Disturbance also impacts vegetation productivity and composition dependent on area affected, intensity, and frequency factors. In this study, a new spatially explicit ecosystem model is presented for the purpose of simulating vegetation cover type changes associated with fire disturbance in the northern Chihuahuan Desert region. The model is called the Landscape and Fire Simulator (LAFS) and represents physiological activity of six functional plant types incorporating site climate, fire, and seed dispersal routines for individual grid cells. We applied this model for Big Bend National Park, Texas, by assessing the impact of wildfire on the trajectory of vegetation communities over time. The model was initialized and calibrated based on landcover maps derived from Landsat-5 Thematic Mapper data acquired in 1986 and 1999 coupled with plant biomass measurements collected in the field during 2000. Initial vegetation cover change analysis from satellite data showed shrub encroachment during this time period that was captured in the simulated results. A synthetic 50-year climate record was derived from historical meteorological data to assess system response based on initial landcover conditions. This simulation showed that shrublands increased to the detriment of grass and yucca-ocotillo vegetation cover types indicating an ecosystem-level trajectory for shrub encroachment. Our analysis of simulated fires also showed that fires significantly reduced site biomass components including leaf area, stem, and seed biomass in this semi-arid ecosystem. In contrast to other landscape simulation models, this new model incorporates detailed physiological responses of functional plant types that will allow us to simulated the impact of increased atmospheric CO2 occurring with climate change coupled with fire

  5. Variability of atmospheric carbonyl sulfide at a semi-arid urban site in western India.

    Science.gov (United States)

    Mallik, Chinmay; Chandra, Naveen; Venkataramani, S; Lal, Shyam

    2016-05-01

    Atmospheric carbonyl sulfide (COS) is a major precursor for sulfate aerosols that play a critical role in climate regulation. Recent studies have highlighted the importance of COS measurements as a reliable means to constrain biospheric carbon assimilation. In a scenario of limited availability of COS data around the globe, we present gas-chromatographic measurements of atmospheric COS mixing ratios over Ahmedabad, a semi-arid, urban region in western India. These measurements, being reported for the first time over an Indian site, enable us to understand the diurnal and seasonal variation in atmospheric COS with respect to its natural, anthropogenic and photochemical sources and sinks. The annual mean COS mixing ratio over Ahmedabad is found to be 0.83±0.43ppbv, which is substantially higher than free tropospheric values for the northern hemisphere. Inverse correlation of COS with soil and skin temperature, suggests that the dry soil of the semi-arid study region is a potential sink for atmospheric COS. Positive correlations of COS with NO2 and CO during post-monsoon and the COS/CO slope of 0.78pptv/ppbv reveals influence of diesel combustion and tire wear. The highest concentrations of COS are observed during pre-monsoon; COS/CO2 slope of 44.75pptv/ppmv combined with information from air mass back-trajectories reveal marshy wetlands spanning over 7500km(2) as an important source of COS in Ahmedabad. COS/CO2 slopes decrease drastically (8.28pptv/ppmv) during post-monsoon due to combined impact of biospheric uptake and anthropogenic emissions. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Hydrologic feasibility of artificial forestation in the semi-arid Loess Plateau of China

    Science.gov (United States)

    Jin, T. T.; Fu, B. J.; Liu, G. H.; Wang, Z.

    2011-08-01

    Hydrologic viability, in terms of moisture availability, is fundamental to ecosystem sustainability in arid and semi-arid regions. In this study, we examine the spatial distribution and after-planting variations of soil moisture content (SMC) in black locust tree (Robinia pseudoacacia L.) plantings in the Loess Plateau of China at a regional scale. Thirty sites (5 to 45 yr old) were selected, spanning an area of 300 km by 190 km in the northern region of the Shaanxi Province. The SMC was measured to a depth of 100 cm at intervals of 10 cm. Geographical, topographic and vegetation information was recorded, and soil organic matter was evaluated. The results show that, at the regional scale, SMC spatial variability was most highly correlated with rainfall. The negative relationship between the SMC at a depth of 20-50 cm and the stand age was stronger than at other depths, although this relationship was not significant at a 5 % level. Watershed analysis shows that the after-planting SMC variation differed depending upon precipitation. The SMC of plantings in areas receiving sufficient precipitation (e.g., mean annual precipitation (MAP) of 617 mm) may increase with stand age due to improvements in soil water-holding capacity and water-retention abilities after planting. For areas experiencing water shortages (e.g., MAP = 509 mm), evapotranspiration may cause planting soils to dry within the first 20 yr of growth. It is expected that, as arid and semi-arid plantings age, evapotranspiration will decrease, and the soil profile may gradually recover. In extremely dry areas (e.g., MAP = 352 mm), the variation in after-planting SMC with stand age was found to be negligible. The MAP can be used as an index to divide the study area into different ecological regions. Afforestation may sequentially exert positive, negative and negligible effects on SMCs with a decrease in the MAP. Therefore, future restoration measures should correspond to the local climate conditions, and the

  7. The GREAT3 challenge

    International Nuclear Information System (INIS)

    Miyatake, H; Mandelbaum, R; Rowe, B

    2014-01-01

    The GRavitational lEnsing Accuracy Testing 3 (GREAT3) challenge is an image analysis competition that aims to test algorithms to measure weak gravitational lensing from astronomical images. The challenge started in October 2013 and ends 30 April 2014. The challenge focuses on testing the impact on weak lensing measurements of realistically complex galaxy morphologies, realistic point spread function, and combination of multiple different exposures. It includes simulated ground- and space-based data. The details of the challenge are described in [1], and the challenge website and its leader board can be found at http://great3challenge.info and http://great3.projects.phys.ucl.ac.uk/leaderboard/, respectively

  8. Nothing Great Is Easy

    OpenAIRE

    Stansbie, Lisa

    2014-01-01

    A solo exhibition of 13 pieces of art work.\\ud \\ud Nothing Great is Easy is an exhibition of sculpture, film, drawing and photography that proposes reconstructed narratives using the sport of swimming and in particular the collective interaction and identity of the channel swimmer. The work utilises the processes, rituals/rules, language and the apparatus of sport.\\ud \\ud “Nothing great is easy” are the words on the memorial to Captain Matthew Webb who was the first man to swim the English ch...

  9. Modelling annual evapotranspiration in a semi-arid, African savanna ...

    African Journals Online (AJOL)

    Accurately measuring evapotranspiration (ET) is essential if we are to derive reasonable estimates of production and water use for semi-arid savannas. Estimates of ET are also important in defining the health of an ecosystem and the quantity of water used by the vegetation when preparing a catchment-scale water balance.

  10. Rainwater harvesting in arid and semi-arid zones

    NARCIS (Netherlands)

    Boers, T.M.

    1994-01-01

    In arid and semi-arid regions, the scarcity of water can be alleviated by rainwater harvesting, which is defined as a method of inducing, collecting, storing, and conserving local surface runoff for agriculture. Rainwater harvesting can be applied with different

  11. Homogenization of the soil surface following fire in semiarid grasslands

    Science.gov (United States)

    Carleton S. White

    2011-01-01

    Semiarid grasslands accumulate soil beneath plant "islands" that are raised above bare interspaces. This fine-scale variation in microtopographic relief is plant-induced and is increased with shrub establishment. Research found that fire-induced water repellency enhanced local-scale soil erosion that reduced variation in microtopographic relief, suggesting...

  12. Determining Dry Matter Degradability of Some Semi-Arid Browse ...

    African Journals Online (AJOL)

    acer

    ABSTRACT: The in vitro gas production of some semi-arid browse species were evaluated. The relationship between in ... between in vitro gas measured on incubation of browse leaves and that calculated from SCFA allows the prediction of SCFA from ... with concentrate feed (40% corn, 10% wheat offal, 10% palm kernel ...

  13. Adaptation at Scale in Semi-Arid Regions | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    People living in Africa and South Asia's semi-arid regions face challenges that hinder their economic growth and development. This project seeks to find proactive, longer-term approaches to climate change adaptation in these vulnerable regions, while helping locals manage existing risks. Short-term focus must shift. So far ...

  14. Uses of tree legumes in semi-arid regions

    Energy Technology Data Exchange (ETDEWEB)

    Felker, P.

    1980-01-01

    Uses of tree legumes in semi-arid and arid regions are reviewed. This review is divided into sections according to the following general use categories: fuels; human food; livestock food; to increase yields of crops grown beneath their canopies;and control of desertification. (MHR)

  15. REPRODUCTIVE ADAPTATIONS OF THE GREEN IGUANA ON A SEMIARID ISLAND

    NARCIS (Netherlands)

    LICHTENBELT, WDV; ALBERS, KB

    1993-01-01

    Reproductive cycle and clutch size were studied in the green iguana (Iguana iguana) on the semiarid Caribbean island of Curacao. The reproductive cycle is correlated with seasonality in rainfall. Mating is in the first half of the dry season, egg laying in the second part of the dry season, and

  16. Paclobutrazol biodegradation in unsaturated soil in the Semi-Arid ...

    African Journals Online (AJOL)

    Paclobutrazol (PBZ) is a plant growth regulator, increasing flowe ring and yield that is widely used in mango cultivation in the semi-arid northeastern Brazil. PBZ remains active in the soil for several years. However, it can severely affect the growth and development of subsequent crops, mainly by reducing vegetative vigor.

  17. The Great Mathematician Project

    Science.gov (United States)

    Goldberg, Sabrina R.

    2013-01-01

    The Great Mathematician Project (GMP) introduces both mathematically sophisticated and struggling students to the history of mathematics. The rationale for the GMP is twofold: first, mathematics is a uniquely people-centered discipline that is used to make sense of the world; and second, students often express curiosity about the history of…

  18. What great managers do.

    Science.gov (United States)

    Buckingham, Marcus

    2005-03-01

    Much has been written about the qualities that make a great manager, but most of the literature overlooks a fundamental question: What does a great manager actually do? While there are countless management styles, one thing underpins the behavior of all great managers. Above all, an exceptional manager comes to know and value the particular quirks and abilities of her employees. She figures out how to capitalize on her staffers' strengths and tweaks her environment to meet her larger goals. Such a specialized approach may seem like a lot of work. But in fact, capitalizing on each person's uniqueness can save time. Rather than encourage employees to conform to strict job descriptions that may include tasks they don't enjoy and aren't good at, a manager who develops positions for his staff members based on their unique abilities will be rewarded with behaviors that are far more efficient and effective than they would be otherwise. This focus on individuals also makes employees more accountable. Because staffers are evaluated on their particular strengths and weaknesses, they are challenged to take responsibility for their abilities and to hone them. Capitalizing on a person's uniqueness also builds a stronger sense of team. By taking the time to understand what makes each employee tick, a great manager shows that he sees his people for who they are. This personal investment not only motivates individuals but also galvanizes the entire team. Finally, this approach shakes up existing hierarchies, which leads to more creative thinking. To take great managing from theory to practice, the author says, you must know three things about a person: her strengths, the triggers that activate those strengths, and how she learns. By asking the right questions, squeezing the right triggers, and becoming aware of your employees' learning styles, you will discover what motivates each person to excel.

  19. The importance of considering rainfall partitioning in afforestation initiatives in semiarid climates: A comparison of common planted tree species in Tehran, Iran

    International Nuclear Information System (INIS)

    Sadeghi, Seyed Mohammad Moein; Attarod, Pedram; Van Stan, John Toland; Pypker, Thomas Grant

    2016-01-01

    As plantations become increasingly important sources of wood and fiber in arid/semiarid places, they have also become increasingly criticized for their hydrological impacts. An examination and comparison of gross rainfall (GR) partitioning across commonly-planted tree species (Pinus eldarica, Cupressus arizonica, Robinia pseudoacacia, and Fraxinus rotundifolia) in semiarid regions has great value for watershed and forest managers interested in managing canopy hydrological processes for societal benefit. Therefore, we performed a field study examining GR partitioning into throughfall (TF), stemflow (SF), and rainfall interception (I) for these species in the semiarid Chitgar Forest Park, Tehran, Iran. An advantage to our study is that we explore the effects of forest structural differences in plantation forests experiencing similar climatic factors and storm conditions. As such, variability in GR partitioning due to different meteorological conditions is minimized, allowing comparison of structural attributes across plantations. Our results show that commonly-selected afforestation species experiencing the same climate produced differing stand structures that differentially partition GR into TF, SF, and I. P. eldarica might be the best of the four species to plant if the primary goal of afforestation is to limit erosion and stormwater runoff as it intercepted more rainfall than other species. However, the high SF generation from F. rotundifolia, and low GR necessary to initiate SF, could maximize retention of water in the soils since SF has been shown to infiltrate along root pathways and access groundwater. A consideration of GR partitioning should be considered when selecting a species for afforestation/reforestation in water-limited ecosystems. - Highlights: • Measured rain partitioning of four most common species used in semiarid afforestation • Species rain partitioning differences are important in a water management. • Recommendations provided to guide

  20. The importance of considering rainfall partitioning in afforestation initiatives in semiarid climates: A comparison of common planted tree species in Tehran, Iran

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi, Seyed Mohammad Moein, E-mail: moeinsadeghi@ut.ac.ir [Department of Forestry and Forest Economics, University of Tehran (Iran, Islamic Republic of); Attarod, Pedram [Department of Forestry and Forest Economics, University of Tehran (Iran, Islamic Republic of); Van Stan, John Toland [Department of Geology and Geography, Georgia Southern University, Statesboro, Georgia (United States); Pypker, Thomas Grant [Department of Natural Resource Sciences, Faculty of Science, Thompson Rivers University, Kamloops (Canada)

    2016-10-15

    As plantations become increasingly important sources of wood and fiber in arid/semiarid places, they have also become increasingly criticized for their hydrological impacts. An examination and comparison of gross rainfall (GR) partitioning across commonly-planted tree species (Pinus eldarica, Cupressus arizonica, Robinia pseudoacacia, and Fraxinus rotundifolia) in semiarid regions has great value for watershed and forest managers interested in managing canopy hydrological processes for societal benefit. Therefore, we performed a field study examining GR partitioning into throughfall (TF), stemflow (SF), and rainfall interception (I) for these species in the semiarid Chitgar Forest Park, Tehran, Iran. An advantage to our study is that we explore the effects of forest structural differences in plantation forests experiencing similar climatic factors and storm conditions. As such, variability in GR partitioning due to different meteorological conditions is minimized, allowing comparison of structural attributes across plantations. Our results show that commonly-selected afforestation species experiencing the same climate produced differing stand structures that differentially partition GR into TF, SF, and I. P. eldarica might be the best of the four species to plant if the primary goal of afforestation is to limit erosion and stormwater runoff as it intercepted more rainfall than other species. However, the high SF generation from F. rotundifolia, and low GR necessary to initiate SF, could maximize retention of water in the soils since SF has been shown to infiltrate along root pathways and access groundwater. A consideration of GR partitioning should be considered when selecting a species for afforestation/reforestation in water-limited ecosystems. - Highlights: • Measured rain partitioning of four most common species used in semiarid afforestation • Species rain partitioning differences are important in a water management. • Recommendations provided to guide

  1. Tree survey and allometric models for tiger bush in northern Senegal and comparison with tree parameters derived from high resolution satellite data

    DEFF Research Database (Denmark)

    Rasmussen, Mads Olander; Goettsche, Frank-M.; Diop, Doudou

    2011-01-01

    A tree survey and an analysis of high resolution satellite data were performed to characterise the woody vegetation within a 10 x 10 km(2) area around a site located close to the town of Dahra in the semiarid northern part of Senegal. The surveyed parameters were tree species, height, tree crown...

  2. Great magnetic storms

    International Nuclear Information System (INIS)

    Tsurutani, B.T.; Yen Te Lee; Tang, F.; Gonzalez, W.D.

    1992-01-01

    The five largest magnetic storms that occurred between 1971 and 1986 are studied to determine their solar and interplanetary causes. All of the events are found to be associated with high speed solar wind streams led by collisionless shocks. The high speed streams are clearly related to identifiable solar flares. It is found that (1) it is the extreme values of the southward interplanetary magnetic fields rather than solar wind speeds that are the primary causes of great magnetic storms, (2) shocked and draped sheath fields preceding the driver gas (magnetic cloud) are at least as effective in causing the onset of great magnetic storms (3 of 5 events ) as the strong fields within the driver gas itself, and (3) precursor southward fields ahead of the high speed streams allow the shock compression mechanism (item 2) to be particularly geoeffective

  3. The great intimidators.

    Science.gov (United States)

    Kramer, Roderick M

    2006-02-01

    After Disney's Michael Eisner, Miramax's Harvey Weinstein, and Hewlett-Packard's Carly Fiorina fell from their heights of power, the business media quickly proclaimed thatthe reign of abrasive, intimidating leaders was over. However, it's premature to proclaim their extinction. Many great intimidators have done fine for a long time and continue to thrive. Their modus operandi runs counter to a lot of preconceptions about what it takes to be a good leader. They're rough, loud, and in your face. Their tactics include invading others' personal space, staging tantrums, keeping people guessing, and possessing an indisputable command of facts. But make no mistake--great intimidators are not your typical bullies. They're driven by vision, not by sheer ego or malice. Beneath their tough exteriors and sharp edges are some genuine, deep insights into human motivation and organizational behavior. Indeed, these leaders possess political intelligence, which can make the difference between paralysis and successful--if sometimes wrenching--organizational change. Like socially intelligent leaders, politically intelligent leaders are adept at sizing up others, but they notice different things. Those with social intelligence assess people's strengths and figure out how to leverage them; those with political intelligence exploit people's weaknesses and insecurities. Despite all the obvious drawbacks of working under them, great intimidators often attract the best and brightest. And their appeal goes beyond their ability to inspire high performance. Many accomplished professionals who gravitate toward these leaders want to cultivate a little "inner intimidator" of their own. In the author's research, quite a few individuals reported having positive relationships with intimidating leaders. In fact, some described these relationships as profoundly educational and even transformational. So before we throw out all the great intimidators, the author argues, we should stop to consider what

  4. Great Lakes Energy Institute

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, J. Iwan [Case Western Reserve Univ., Cleveland, OH (United States)

    2012-11-18

    The vision of the Great Lakes Energy Institute is to enable the transition to advanced, sustainable energy generation, storage, distribution and utilization through coordinated research, development, and education. The Institute will place emphasis on translating leading edge research into next generation energy technology. The Institute’s research thrusts focus on coordinated research in decentralized power generation devices (e.g. fuel cells, wind turbines, solar photovoltaic devices), management of electrical power transmission and distribution, energy storage, and energy efficiency.

  5. Climate change, groundwater and intensive commercial farming in the semi-arid northern Sandveld, South Africa

    CSIR Research Space (South Africa)

    Archer van Garderen, Emma RM

    2009-06-01

    Full Text Available practice guidelines for undertaking intensive commercial agriculture in a sensitive biodiverse environment. The study suggests that climate change may make the achievement of such better practice significantly more challenging. Climate change is here seen...

  6. Chapter 13. Current management situation: Great gray owls

    Science.gov (United States)

    Jon Verner

    1994-01-01

    The breeding range of great gray owls (Strix nebulosa) in the United States includes portions of Alaska, mountains in the western United States including portions of the Cascades and Sierra Nevada ranges and the northern Rockies, and portions of Minnesota, Michigan, Wisconsin, and New York (see Chapter 14 and Map 3). The species is sometimes observed...

  7. Idiopathic great saphenous phlebosclerosis.

    Directory of Open Access Journals (Sweden)

    Ahmadreza Jodati

    2013-06-01

    Full Text Available Arterial sclerosis has been extensively described but reports on venous sclerosis are very sparse. Phlebosclerosis refers to the thickening and hardening of the venous wall. Despite its morphological similarities with arteriosclerosis and potential morbid consequences, phlebosclerosis has gained only little attention. We report a 72 year old male with paralysis and atrophy of the right leg due to childhood poliomyelitis who was referred for coronary artery bypass surgery. The great saphenous vein, harvested from the left leg, showed a hardened cord-like obliterated vein. Surprisingly, harvested veins from the atrophic limb were normal and successfully used for grafting.

  8. Great software debates

    CERN Document Server

    Davis, A

    2004-01-01

    The industry’s most outspoken and insightful critic explains how the software industry REALLY works. In Great Software Debates, Al Davis, shares what he has learned about the difference between the theory and the realities of business and encourages you to question and think about software engineering in ways that will help you succeed where others fail. In short, provocative essays, Davis fearlessly reveals the truth about process improvement, productivity, software quality, metrics, agile development, requirements documentation, modeling, software marketing and sales, empiricism, start-up financing, software research, requirements triage, software estimation, and entrepreneurship.

  9. Making Psychotherapy Great Again?

    Science.gov (United States)

    Plakun, Eric M

    2017-05-01

    Psychotherapy never stopped being as "great" as other treatments. This column explores the evidence base for both psychotherapy and medications, using depression as a specific example. The limitations are comparable for psychotherapy and medication, with much of the evidence based on small degrees of "statistically significant" rather than "clinically meaningful" change. Our field's biomedical emphasis leads to a false assumption that most patients present with single disorders, when comorbidity is the rule rather than the exception. This false assumption contributes to limitations in the evidence base and in our ability to treat patients optimally.

  10. Study on Applicability of Conceptual Hydrological Models for Flood Forecasting in Humid, Semi-Humid Semi-Arid and Arid Basins in China

    Directory of Open Access Journals (Sweden)

    Guangyuan Kan

    2017-09-01

    Full Text Available Flood simulation and forecasting in various types of watersheds is a hot issue in hydrology. Conceptual hydrological models have been widely applied to flood forecasting for decades. With the development of economy, modern China faces with severe flood disasters in all types of watersheds include humid, semi-humid semi-arid and arid watersheds. However, conceptual model-based flood forecasting in semi-humid semi-arid and arid regions is still challenging. To investigate the applicability of conceptual hydrological models for flood forecasting in the above mentioned regions, three typical conceptual models, include Xinanjiang (XAJ, mix runoff generation (MIX and northern Shannxi (NS, are applied to 3 humid, 3 semi-humid semi-arid, and 3 arid watersheds. The rainfall-runoff data of the 9 watersheds are analyzed based on statistical analysis and information theory, and the model performances are compared and analyzed based on boxplots and scatter plots. It is observed the complexity of drier watershed data is higher than that of the wetter watersheds. This indicates the flood forecasting is harder in drier watersheds. Simulation results indicate all models perform satisfactorily in humid watersheds and only NS model is applicable in arid watersheds. Model with consideration of saturation excess runoff generation (XAJ and MIX perform better than the infiltration excess-based NS model in semi-humid semi-arid watersheds. It is concluded more accurate mix runoff generation theory, more stable and efficient numerical solution of infiltration equation and rainfall data with higher spatial-temporal resolution are main obstacles for conceptual model-based flood simulation and forecasting.

  11. Ecosystem properties of semiarid savanna grassland in West Africa and its relationship with environmental variability.

    Science.gov (United States)

    Tagesson, Torbern; Fensholt, Rasmus; Guiro, Idrissa; Rasmussen, Mads Olander; Huber, Silvia; Mbow, Cheikh; Garcia, Monica; Horion, Stéphanie; Sandholt, Inge; Holm-Rasmussen, Bo; Göttsche, Frank M; Ridler, Marc-Etienne; Olén, Niklas; Lundegard Olsen, Jørgen; Ehammer, Andrea; Madsen, Mathias; Olesen, Folke S; Ardö, Jonas

    2015-01-01

    The Dahra field site in Senegal, West Africa, was established in 2002 to monitor ecosystem properties of semiarid savanna grassland and their responses to climatic and environmental change. This article describes the environment and the ecosystem properties of the site using a unique set of in situ data. The studied variables include hydroclimatic variables, species composition, albedo, normalized difference vegetation index (NDVI), hyperspectral characteristics (350-1800 nm), surface reflectance anisotropy, brightness temperature, fraction of absorbed photosynthetic active radiation (FAPAR), biomass, vegetation water content, and land-atmosphere exchanges of carbon (NEE) and energy. The Dahra field site experiences a typical Sahelian climate and is covered by coexisting trees (~3% canopy cover) and grass species, characterizing large parts of the Sahel. This makes the site suitable for investigating relationships between ecosystem properties and hydroclimatic variables for semiarid savanna ecosystems of the region. There were strong interannual, seasonal and diurnal dynamics in NEE, with high values of ~-7.5 g C m(-2)  day(-1) during the peak of the growing season. We found neither browning nor greening NDVI trends from 2002 to 2012. Interannual variation in species composition was strongly related to rainfall distribution. NDVI and FAPAR were strongly related to species composition, especially for years dominated by the species Zornia glochidiata. This influence was not observed in interannual variation in biomass and vegetation productivity, thus challenging dryland productivity models based on remote sensing. Surface reflectance anisotropy (350-1800 nm) at the peak of the growing season varied strongly depending on wavelength and viewing angle thereby having implications for the design of remotely sensed spectral vegetation indices covering different wavelength regions. The presented time series of in situ data have great potential for dryland dynamics

  12. Adverbial descriptions in Northern Sotho | Pretorius | South African ...

    African Journals Online (AJOL)

    Important language strategies, such as the use of auxiliary word groups and ideophones in expressing adverbial meanings are, to a great extent, neglected in most popular Northern Sotho grammars. Owing to the fact that in most cases, no one-to-one lexical equivalence exists between Northern Sotho and for instance ...

  13. Semi-arid development: competitiveness factors in biodiesel productive chain

    OpenAIRE

    Breno Barros Telles do Carmo; Dmontier Pinheiro Aragão; Heráclito Lopes Jaguaribe Pontes; Bruno Magalhães Ribeiro; Marcos Ronaldo Albertin

    2009-01-01

    The new global market competitiveness considerer the competition between productive chains (PC) or supply chains, not just between enterprises. In this case, it can be observed collaboration and cooperation enterprises that dispute with others productives chain. The PC competitiveness can be impaired if is subject by inhibitors factors, that can impairer the performance. This paper analyses these competitiveness factors inhibitors in biodiesel productive chain (CPB) in semi-arid area: exporte...

  14. Excessive reliance on afforestation in China's arid and semi-arid regions: Lessons in ecological restoration

    Science.gov (United States)

    Cao, Shixiong; Chen, Li; Shankman, David; Wang, Chunmei; Wang, Xiongbin; Zhang, Hong

    2011-02-01

    Afforestation is a primary tool for controlling desertification and soil erosion in China. Large-scale afforestation, however, has complex and poorly understood consequences for the structure and composition of future ecosystems. Here, we discuss the potential links between China's historical large-scale afforestation practices and the program's effects on environmental restoration in arid and semi-arid regions in northern China based on a review of data from published papers, and offer recommendations to overcome the shortcomings of current environmental policy. Although afforestation is potentially an important approach for environmental restoration, current Chinese policy has not been tailored to local environmental conditions, leading to the use of inappropriate species and an overemphasis on tree and shrub planting, thereby compromising the ability to achieve environmental policy goals. China's huge investment to increase forest cover seems likely to exacerbate environmental degradation in environmentally fragile areas because it has ignored climate, pedological, hydrological, and landscape factors that would make a site unsuitable for afforestation. This has, in many cases, led to the deterioration of soil ecosystems and decreased vegetation cover, and has exacerbated water shortages. Large-scale and long-term research is urgently needed to provide information that supports a more effective and flexible environmental restoration policy.

  15. Forest carbon sinks in the Northern Hemisphere

    Science.gov (United States)

    Christine L. Goodale; Michael J. Apps; Richard A. Birdsey; Christopher B. Field; Linda S. Heath; Richard A. Houghton; Jennifer C. Jenkins; Gundolf H. Kohlmaier; Werner Kurz; Shirong Liu; Gert-Jan Nabuurs; Sten Nilsson; Anatoly Z. Shvidenko

    2002-01-01

    There is general agreement that terrestrial systems in the Northern Hemisphere provide a significant sink for atmospheric CO2; however, estimates of the magnitude and distribution of this sink vary greatly. National forest inventories provide strong, measurement-based constraints on the magnitude of net forest carbon uptake. We brought together...

  16. Great Britain at CERN

    CERN Multimedia

    2006-01-01

    From 14 to 16 November 2006 Administration Building, Bldg. 60/61 - ground and 1st floor 09.30 - 17.30 Fifteen companies will present their latest technologies at the 'Great Britain at CERN' exhibition. British industry will exhibit products and technologies related to the field of particle physics. The main fields represented will be computing technologies, electrical engineering, electronics, mechanical engineering, vacuum & low temperature technologies and particle detectors. The exhibition is organised by BEAMA Exhibitions (the British Electrotechnical and Allied Manufacturers Association). Below you will find: a list of the exhibitors. A detailed programme will be available in due course: from your Departmental secretariat, from the Reception information desk, Building 33, at the exhibition itself. A detailed list of the companies is available at the following FI link: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm LIST OF EXHIBITORS 3D Metrics Almat...

  17. Great Britain at CERN

    CERN Multimedia

    2006-01-01

    From 14 to 16 November 2006 Administration Building, Bldg. 60/61 - ground and 1st floor 09.30 - 17.30 Fifteen companies will present their latest technologies at the 'Great Britain at CERN' exhibition. British industry will exhibit products and technologies related to the field of particle physics. The main fields represented will be computing technologies, electrical engineering, electronics, mechanical engineering, vacuum & low temperature technologies and particle detectors. The exhibition is organised by BEAMA Exhibitions (the British Electrotechnical and Allied Manufacturers Association). Below you will find: a list of the exhibitors. A detailed programme will be available in due course: from your Departmental secretariat, from the Reception information desk, Building 33, at the exhibition itself. A detailed list of the companies is available at the following FI link: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm LIST OF EXHIBITORS 3D Metrics Alma...

  18. Effectiveness of conservation agriculture practices on soil erosion processes in semi-arid areas of Zimbabwe

    Science.gov (United States)

    Chikwari, Emmanuel; Mhaka, Luke; Gwandu, Tariro; Chipangura, Tafadzwa; Misi Manyanga, Amos; Sabastian Matsenyengwa, Nyasha; Rabesiranana, Naivo; Mabit, Lionel

    2016-04-01

    years before being conventionally tilled. Despite lower fallout in the southern hemisphere than in the northern hemisphere, this study demonstrates the potential of the Cs-137 technique in assessing field-scale variations of soil loss and redistribution arising from different agricultural management practices in semi-arid areas of Zimbabwe.

  19. Variations of Near Surface Energy Balance Caused by Land Cover Changes in the Semiarid Grassland Area of China

    Directory of Open Access Journals (Sweden)

    Qun’ou Jiang

    2014-01-01

    Full Text Available This study applies the Dynamics of Land System (DLS model to simulating the land cover under the designed scenarios and then analyzes the effects of land cover conversion on energy flux in the semiarid grassland area of China with the Weather Research and Forecasting (WRF model. The results indicate that the grassland will show a steadily upgrowing trend under the coordinated environmental sustainability (CES scenario. Compared to the CES scenario, the rate of increase in grassland cover is lower, while the rate of increase in urban land cover will be higher under the rapid economic growth (REG scenario. Although the conversion from cropland to grassland will reduce the energy flux, the expansion of urban area and decreasing of forestry area will bring about more energy flux. As a whole, the energy flux of near surface will obviously not change under the CES scenario, and the climate therefore will not be possible to be influenced greatly by land cover change. The energy flux under the REG scenario is higher than that under the CES scenario. Those research conclusions can offer valuable information for the land use planning and climate change adaptation in the semiarid grassland area of China.

  20. [Sowing date of corn in semiarid region of Jilin Province, Northeast China in adapting to climate change].

    Science.gov (United States)

    Jin, Ying-Hua; Zhou, Dao-Wei; Qin, Li-Jie

    2012-10-01

    Under the background of global climate change, the climate in semiarid region of west Jilin Province changed greatly, producing a profound impact on the corn production in this region. In this study, the corn seeds were under three treatments (accelerating germination at 10 and 25 degrees C, and dry seeds), and a field experiment with early sowing and traditional sowing was conducted in 2008 to investigate the effects of early sowing these seeds on the seedling emergence, growth, and yield, and compare the effects of early sowing and traditional sowing dates on the corn production and yield. In 1961-2010, the first day of the growth season of corn in semiarid region of west Jilin Province was advanced, the air temperature increased significantly, and the precipitation displayed a decreasing trend. At present, the corn sowing date in this region could be advanced to 11th, April. Accelerating germination at 10 degrees C, directly sowing dry seeds, and bed-irrigation sowing all benefited the seedling emergence and cold resistance of early-sown seeds, and the corn plant height and leaf area under early sowing were significantly higher, with the yield increased by 35% - 48%, compared with those under traditional sowing.

  1. Review: The Great Gatsby

    Directory of Open Access Journals (Sweden)

    Antonia de Jesus Sales

    2016-08-01

    Full Text Available A presente resenha busca discutir a tradução de The Great Gatsby para o contexto brasileiro. Diversas traduções foram feitas, em diversas épocas e com repercussão positiva no contexto brasileiro. Para o presente estudo, foi observada a tradução de Vanessa Bárbara, de 2011. Nesse sentido, o aspecto biográficos do autor e a forma como se apresentam os personagens na obra são fatores de cotejamento na obra original e na tradução brasileira. Francis Scott Key Fitzgerald (1896 – 1940 é famoso por ter em suas obras traços biográficos, algo que certamente influencia o leitor que adentra a sua obra. Quanto à recepção de O Grande Gatsby no contexto brasileiro, há que se considerar que O Grande Gatsby teve diversas traduções no Brasil. Depois dessa tradução de Vanessa Bárbara, em 2011, outras três vieram em 2013, juntamente com o filme. Há que considerar os aspectos comerciais embutidos nessas traduções e que muito corroboram para o resultado final. Prova disso são as capas, que são sempre diferenciadas em cada edição lançada. O tradutor nem sempre pode opinar sobre questões como estas. A tradução, a meu ver, é uma obra de qualidade, visto que a tradutora buscou ser fiel, sem dificultar a interpretação da obra para o leitor.

  2. Review: The Great Gatsby

    Directory of Open Access Journals (Sweden)

    Antonia de Jesus Sales

    2016-05-01

    Full Text Available A presente resenha busca discutir a tradução de The Great Gatsby para o contexto brasileiro. Diversas traduções foram feitas, em diversas épocas e com repercussão positiva no contexto brasileiro. Para o presente estudo, foi observada a tradução de Vanessa Bárbara, de 2011. Nesse sentido, o aspecto biográficos do autor e a forma como se apresentam os personagens na obra são fatores de cotejamento na obra original e na tradução brasileira. Francis Scott Key Fitzgerald (1896 – 1940 é famoso por ter em suas obras traços biográficos, algo que certamente influencia o leitor que adentra a sua obra. Quanto à recepção de O Grande Gatsby no contexto brasileiro, há que se considerar que O Grande Gatsby teve diversas traduções no Brasil. Depois dessa tradução de Vanessa Bárbara, em 2011, outras três vieram em 2013, juntamente com o filme. Há que considerar os aspectos comerciais embutidos nessas traduções e que muito corroboram para o resultado final. Prova disso são as capas, que são sempre diferenciadas em cada edição lançada. O tradutor nem sempre pode opinar sobre questões como estas. A tradução, a meu ver, é uma obra de qualidade, visto que a tradutora buscou ser fiel, sem dificultar a interpretação da obra para o leitor.

  3. Great Lakes Environmental Database (GLENDA)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Great Lakes Environmental Database (GLENDA) houses environmental data on a wide variety of constituents in water, biota, sediment, and air in the Great Lakes area.

  4. Pathways to Resilience in Semi-Arid Economies | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Pathways to Resilience in Semi-Arid Economies. How can populations become resilient to climate change while pursuing economic growth? This question is at the heart of a research project designed to support climate-resilient economic development in semi-arid lands. It will do so by addressing the conditions for ...

  5. The challenges of rehabilitating denuded patches of a semi-arid environment in Kenya

    NARCIS (Netherlands)

    Mganga, K.Z.; Nyangito, M.M.; Musimba, N.K.R.; Nyariki, D.M.; Mwangombe, A.W.; Ekaya, W.N.; Muiri, W.M.; Clavel, D.; Francis, J.; Kaufmann, Von R.; Verhagen, J.

    2010-01-01

    Land degradation is a major problem in the semi-arid environments of Sub-Saharan Africa. Fighting land degradation is essential to ensure the sustainable and long-term productivity of the habited semiarid lands. In Kenya, grass reseeding technology has been used to combat land degradation. However,

  6. Soil Chemistry after Irrigation with Treated Wastewater in Semiarid Climate

    Directory of Open Access Journals (Sweden)

    Pedro Carlos Pacheco de Oliveira

    2016-01-01

    Full Text Available ABSTRACT Soil irrigation using treated wastewater in the Brazilian semiarid region is a promising practice as this area currently faces water scarcity and pollution of water resources by domestic sewage. The aim of this study was to evaluate the use of treated wastewater in drip irrigation and its effect on the chemistry of soil cultivated with squash (Cucurbita maxima Duch. Coroa IAC and to verify whether there was an increase in soil salinity under a semiarid climate. The experiment was conducted for 123 days on a farm close to the sewage treatment plant, in a randomized block design with five treatments and four replications. The treatments consisted of two irrigation water depths (100 and 150 % of the evapotranspiration, two applications of gypsum to attenuate wastewater sodicity (0 and 5.51 g per plant, and a control treatment with no application of wastewater or gypsum. During the experiment, treated wastewater and soil gravitational water, at a depth of 0.40 m, were collected for measurement of Na+, K+, Ca2+, Mg2+, NO−3, NH4+, Cl− , alkalinity, electrical conductivity, pH and sodium adsorption ratio. At the end of the experiment, soil samples were collected at depths of 0.00-0.10, 0.10-0.20, and 0.20-0.40 m; and pH, total N, organic C, exchangeable cations and electrical conductivity of the saturation extract (CEs were analyzed. Besides an increase in pH and a reduction in total N, the irrigation with wastewater reduces soil salinity of the naturally salt-rich soils of the semiarid climate. It also led to soil sodification, in spite of the added gypsum, which indicates that irrigation with wastewater might require the addition of greater quantities of gypsum to prevent physical degradation of the soil.

  7. Wind and water erosion control on semiarid lands

    International Nuclear Information System (INIS)

    Siddoway, F.H.

    1980-01-01

    Commercial crop production on semiarid lands is difficult because insufficient water is often present to manage the system effectively. Erosion control presents the major management problem. The factors contributing to wind erosion and their interaction have been quantified into a wind erosion equation. The control of wind erosion through agronomic alteration of the various factors is discussed. The quantification and control of water erosion is also discussed with respect to the Universal Soil Loss Equation. Radioisotopes tracers have been used in conjunction with these erosion equations to measure soil losses. (author)

  8. Pythiosis in dogs in the semiarid region of Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Maria T.S. Frade

    Full Text Available ABSTRACT: We describe the epidemiological, clinical and pathological features of five cases of pythiosis in dogs in northeast semiarid. The disease occurred in dogs with age between one and three years, females and males of different breeds. The dogs were created in urban areas, but were occasionally taken to the countryside and then had contact with wetlands. The main clinical signs were weight loss, vomiting, diarrhea and tenesmus. Macroscopically there were intestinal wall thickening with irregular firm masses with yellowish granular areas interspersed with a whitish tissue, involving the duodenum, colon and rectum, extending to the lymph nodes and pancreas, and the vagina and liver. In the skin there were areas of alopecia and irregular ulcerations, some containing small cavitations with serosanguineous secretion. Microscopically there were pyogranulomatous inflammation and in one case also there were eosinophilic necrosis associated with negative images tubuliformes by hematoxylin and eosin, strongly stained by GMS and weakly by PAS. Hyphae were strongly marked by immunohistochemistry with polyclonal anti-Pythium insidiosum. The disease occurs sporadically in dogs in the semiarid Northeast, however should be included in the differential diagnosis of chronic diseases and proliferative aspect of the gastrointestinal system, and front skin lesions of difficult treatment.

  9. Using NDVI to measure precipitation in semi-arid landscapes

    Science.gov (United States)

    Birtwhistle, Amy N.; Laituri, Melinda; Bledsoe, Brian; Friedman, Jonathan M.

    2016-01-01

    Measuring precipitation in semi-arid landscapes is important for understanding the processes related to rainfall and run-off; however, measuring precipitation accurately can often be challenging especially within remote regions where precipitation instruments are scarce. Typically, rain-gauges are sparsely distributed and research comparing rain-gauge and RADAR precipitation estimates reveal that RADAR data are often misleading, especially for monsoon season convective storms. This study investigates an alternative way to map the spatial and temporal variation of precipitation inputs along ephemeral stream channels using Normalized Difference Vegetation Index (NDVI) derived from Landsat Thematic Mapper imagery. NDVI values from 26 years of pre- and post-monsoon season Landsat imagery were derived across Yuma Proving Ground (YPG), a region covering 3,367 km2 of semiarid landscapes in southwestern Arizona, USA. The change in NDVI from a pre-to post-monsoon season image along ephemeral stream channels explained 73% of the variance in annual monsoonal precipitation totals from a nearby rain-gauge. In addition, large seasonal changes in NDVI along channels were useful in determining when and where flow events have occurred.

  10. Contamination of semiarid potiguar reservoirs by harmful bacteria

    Directory of Open Access Journals (Sweden)

    Ermeton Duarte do Nascimento

    2016-04-01

    Full Text Available Water contamination in the semi-arid section of Northeast Brazil is a current concern for the country’s researchers, since this region is considered one of the poorest in Brazil and the water in these locations is a primary vehicle for disease transmission. We collected physical and chemical data as well as water samples from four semiarid potiguar reservoirs during the dry and rainy seasons of 2013 and 2014. These samples were prepared in a laboratory at the Federal University of Rio Grande do Norte (UFRN and their physical, chemical and microbiological characteristics were evaluated. The procedures of microbial isolation and identification followed the Standard Methods for Examinations of Water and Wastewater. Then Vitek II system (Bio-Merieux® was used to identify the microbial specimens and we calculated the frequency of specimens’ occurrence. Altogether, 168 bacteria were isolated and identified; 97% were Gram-negative and only 3% were Gram-positive. Within the Gram negatives, 73.2% were identified as belonging to the Enterobacteriaceae family and, in general terms, the most constant genera in the water reservoirs were Vibrio and Aeromonas. Among the Enterobacteriaceae family, the species Escherichia coli, Enterobacter cloacae complex and Klebsiella pneumoniae were the most frequent. There was no statistical difference between the number or morphotype groups found in the periods, p=0.255 and p=0.237, respectively. The analyzed data indicate possible contamination of these water reservoirs by human and/or animal fecal material.

  11. Composition and fate of mine- and smelter-derived particulates in soils from humid subtropical and semiarid areas

    Science.gov (United States)

    Ettler, Vojtech; Kribek, Bohdan; Mihaljevic, Martin; Vanek, Ales; Penizek, Vit; Sracek, Ondra; Mapani, Ben; Kamona, Fred; Nyambe, Imasiku

    2017-04-01

    Soils in the vicinity of non-ferrous metal smelters are often highly polluted by inorganic contaminants released from particulate emissions, which undergo weathering processes and release contaminants when deposited in soils. We studied the heavy mineral fraction, separated from mining- and smelter-affected topsoils, from both a humid subtropical area in the Zambian Copperbelt and a hot semi-arid area in the northern Namibia. High concentrations of metal(loid)s were detected in the studied soils: up to 1450 ppm As, 8980 ppm Cu, 4640 ppm Pb, 2620 ppm Zn. A combination of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM/EDS), and electron probe microanalysis (EPMA) helped to identify the phases forming individual metal(loid)-bearing particles. Whereas spherical particles originate from the smelting and flue gas cleaning processes, angular particles either have geogenic origins or they are windblown from the mining operations and mine waste disposal sites. Sulphides from ores and mine tailings often exhibit weathering rims in contrast to smelter-derived high-temperature sulphides (chalcocite [Cu2S], digenite [Cu9S5], covellite [CuS], non-stoichiometric quenched Cu-Fe-S phases). Soils from humid subtropical areas exhibit higher available concentrations of metal(loids), and higher frequencies of weathering features (especially for copper-bearing oxides such as delafossite [CuFeO2]) are observed. In contrast, metal(loid)s are efficiently retained in semi-arid soils, where a high proportion of non-weathered smelter slag particles and low-solubility Ca-Cu-Pb arsenates occur. Our results indicate that compared to semi-arid areas (where inorganic contaminants were rather immobile in soils despite their high concentrations) a higher potential risk exists for agriculture in mine- and smelter-affected humid subtropical areas (where metal(loid) contaminants can be highly available for the uptake by crops). This study was supported by the Czech Science

  12. Antecedent Moisture and Biological Inertia as Predictors of Plant and Ecosystem Productivity in Arid and Semiarid Systems

    Science.gov (United States)

    Ogle, K.

    2011-12-01

    Many plant and ecosystem processes in arid and semiarid systems may be affected by antecedent environmental conditions (e.g., precipitation patterns, soil water availability, temperature) that integrate over past days, weeks, months, seasons, or years. However, the importance of such antecedent exogenous effects relative to conditions occurring at the time of the observed process is relatively unexplored. Even less is known about the potential importance of antecedent endogenous effects that describe the influence of past ecosystem states on the current ecosystem state; e.g., how is current ecosystem productivity related to past productivity patterns? We hypothesize that incorporation of antecedent exogenous and endogenous factors can improve our predictive understanding of many plant and ecosystem processes, especially in arid and semiarid ecosystems. Furthermore, the common approach to quantifying the effects of antecedent (exogenous) variables relies on arbitrary, deterministic definitions of antecedent variables that (1) may not accurately describe the role of antecedent conditions and (2) ignore uncertainty associated with applying deterministic definitions. In this study, we employ a stochastic framework for (1) computing the antecedent variables that estimates the relative importance of conditions experienced each time unit into the past, also providing insight into potential lag responses, and (2) estimating the effect of antecedent factors on the response variable of interest. We employ this approach to explore the potential roles of antecedent exogenous and endogenous influences in three settings that illustrate the: (1) importance of antecedent precipitation for net primary productivity in the shortgrass steppe in northern Colorado, (2) dependency of tree growth on antecedent precipitation and past growth states for pinyon growing in western Colorado, and (3) influence of antecedent soil water and prior root status on observed root growth in the Mojave

  13. Minimizing risk associated with shallow burial of waste in semiarid ecosystems: Erosion and vegetation dynamics

    International Nuclear Information System (INIS)

    Breshears, D.D.; Martens, S.N.; Nyhan, J.W.; Springer, E.P.; Wilcox, B.P.

    1994-01-01

    Numerous regulations govern the disposal of low-level radioactive and hazardous waste by burial in shallow pits. The overall goal of these regulations is to reduce the risk to humans and components of the ecosystem for 500 to 1 000 years. Erosional loss of the soil profile covering waste and contamination of groundwater by leachate are two pathways that influence human and ecological risks. Screening calculations for a waste site in a pinyon-juniper woodland at Los Alamos National Laboratory predict the entire 2 m cover of a waste site could be lost by erosion in less than 500 years. In contrast, less than 0.001% of the waste would reach groundwater by leachate. Predicted erosion rates depend highly on plant cover. The boundary between ponderosa pine forest and pinyon-juniper woodland has shifted more than 1 km in less than 50 years in the Los Alamos region and additional boundary shifts have been hypothesized in conjunction with global warming. High erosion rates (> 0.2 cm per year) have been measured in these transition zones. In concert, these results suggest that risk associated with erosional loss of the waste site cover may greatly exceed risks associated with groundwater contamination in semiarid ecosystems

  14. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium; Comunicacion recibida del Reino Unido de Gran Bretana e Irlanda del Norte en relacion con sus politicas referentes a la gestion del plutonio. Declaraciones sobre la gestion del plutonio y del uranio muy enriquecido

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-19

    The Secretariat has received a note verbale dated 6 June 2011 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2010 [Spanish] La Secretaria ha recibido una nota verbal, de fecha 6 de junio de 2011, de la Mision Permanente del Reino Unido de Gran Bretana e Irlanda del Norte ante el OIEA, en cuyos anexos el Gobierno, en cumplimiento de su compromiso contraido en virtud de las Directrices para la gestion del plutonio (transcritas en el documento INFCIRC/549 de 22 de junio de 1998 y denominadas en adelante las 'directrices') y de conformidad con los anexos B y C de las directrices, presenta las cifras anuales de sus existencias de plutonio no irradiado de uso civil y las cantidades estimadas de plutonio contenido en el combustible gastado de reactores de uso civil, a 31 de diciembre de 2010.

  15. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium; Comunicacion recibida del Reino Unido de Gran Bretana e Irlanda del Norte en relacion con sus politicas referentes a la gestion del plutonio. Declaraciones sobre la gestion del plutonio y del uranio muy enriquecido

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-13

    The Secretariat has received a note verbale dated 28 July 2010 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines'), and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2009 [Spanish] La Secretaria ha recibido una nota verbal, de fecha 28 de julio de 2010, de la Mision Permanente del Reino Unido de Gran Bretana e Irlanda del Norte ante el OIEA, en cuyos anexos el Gobierno, en cumplimiento de su compromiso contraido en virtud de las Directrices para la gestion del plutonio (transcritas en el documento INFCIRC/549 de 16 de marzo de 1998 y denominadas en adelante las 'directrices') y de conformidad con los anexos B y C de las directrices, presenta las cifras anuales de sus existencias de plutonio no irradiado de uso civil y las cantidades estimadas de plutonio contenido en el combustible gastado de reactores de uso civil, a 31 de diciembre de 2009.

  16. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium; Comunicacion recibida del Reino Unido de Gran Bretana e Irlanda del Norte en relacion con sus politicas referentes a la gestion del plutonio. Declaraciones sobre la gestion del plutonio y del uranio muy enriquecido

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-10-30

    The Secretariat has received a note verbale dated 26 June 2009 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the IAEA in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2008 [Spanish] La Secretaria ha recibido una nota verbal, de fecha 26 de junio de 2009, de la Mision Permanente del Reino Unido de Gran Bretana e Irlanda del Norte ante el OIEA, en cuyos anexos el Gobierno, en cumplimiento de su compromiso contraido en virtud de las Directrices para la gestion del plutonio (transcritas en el documento INFCIRC/549 de 22 de junio de 1998 y denominadas en adelante las 'directrices') y de conformidad con los anexos B y C de las directrices, presenta las cifras anuales de sus existencias de plutonio no irradiado de uso civil y las cantidades estimadas de plutonio contenido en el combustible gastado de reactores de uso civil, a 31 de diciembre de 2008.

  17. Communication Received from the United Kingdom of Great Britain and Northern Ireland Concerning Its Policies Regarding the Management of Plutonium. Statements on the Management of Plutonium and of High Enriched Uranium; Comunicacion recibida del Reino Unido de Gran Bretana e Irlanda del Norte en relacion con sus politicas referentes a la gestion del plutonio. Declaraciones sobre la gestion del plutonio y del uranio muy enriquecido

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-09-25

    The Secretariat has received a Note Verbale dated 23 August 2007 from the Permanent Mission of the United Kingdom of Great Britain and Northern Ireland to the United Nations and the International Organizations in Vienna in the enclosures of which the Government, in keeping with its commitment under the Guidelines for the Management of Plutonium (contained in INFCIRC/549 of 16 March 1998 and hereinafter referred to as the 'Guidelines') and in accordance with Annexes B and C of the Guidelines, has made available annual figures for its holdings of civil unirradiated plutonium and the estimated amounts of plutonium contained in spent civil reactor fuel as of 31 December 2006 [Spanish] La Secretaria ha recibido una nota verbal, de fecha 23 de agosto de 2007, de la Mision Permanente del Reino Unido de Gran Bretana e Irlanda del Norte ante las Naciones Unidas y las Organizaciones Internacionales con sede en Viena, en cuyos anexos el Gobierno, en cumplimiento de su compromiso contraido en virtud de las Directrices para la gestion del plutonio (transcritas en el documento INFCIRC/549 de 16 de marzo de 1998 y denominadas en adelante las 'Directrices') y de conformidad con los anexos B y C de las Directrices, presenta las cifras anuales de sus existencias de plutonio no irradiado de uso civil y las cantidades estimadas de plutonio contenido en el combustible gastado de reactores de uso civil, a 31 de diciembre de 2006.

  18. Convergent responses of nitrogen and phosphorus resorption to nitrogen inputs in a semiarid grassland

    Science.gov (United States)

    Lü, Xiao-Tao; Reed, Sasha; Yu, Qiang; He, Nian-Peng; Wang, Zheng-Wen; Han, Xing-Guo

    2013-01-01

    Human activities have significantly altered nitrogen (N) availability in most terrestrial ecosystems, with consequences for community composition and ecosystem functioning. Although studies of how changes in N availability affect biodiversity and community composition are relatively common, much less remains known about the effects of N inputs on the coupled biogeochemical cycling of N and phosphorus (P), and still fewer data exist regarding how increased N inputs affect the internal cycling of these two elements in plants. Nutrient resorption is an important driver of plant nutrient economies and of the quality of litter plants produce. Accordingly, resorption patterns have marked ecological implications for plant population and community fitness, as well as for ecosystem nutrient cycling. In a semiarid grassland in northern China, we studied the effects of a wide range of N inputs on foliar nutrient resorption of two dominant grasses, Leymus chinensis and Stipa grandis. After 4 years of treatments, N and P availability in soil and N and P concentrations in green and senesced grass leaves increased with increasing rates of N addition. Foliar N and P resorption significantly decreased along the N addition gradient, implying a resorption-mediated, positive plant–soil feedback induced by N inputs. Furthermore, N : P resorption ratios were negatively correlated with the rates of N addition, indicating the sensitivity of plant N and P stoichiometry to N inputs. Taken together, the results demonstrate that N additions accelerate ecosystem uptake and turnover of both N and P in the temperate steppe and that N and P cycles are coupled in dynamic ways. The convergence of N and P resorption in response to N inputs emphasizes the importance of nutrient resorption as a pathway by which plants and ecosystems adjust in the face of increasing N availability.

  19. The role of upland wetlands in modulating snowmelt runoff in the semi-arid Andes

    Science.gov (United States)

    Hevia, Andres; Sproles, Eric; Soulsby, Chris; Tetzlaff, Doerthe

    2016-04-01

    The wetlands, or bofedales, of semi-arid northern central Chile (29°-32°S) provide a critical store of water that modulate spring snowmelt runoff. Water released from bofedales helps sustain flows throughout the dry portions of the year, providing fresh water to downstream residents and a robust tourist, agricultural, and mining economy. In the Río Claro watershed (30°S, 1515 km2, 800m to 5500 m a.s.l.) a series fourteen bofedales have formed at natural choke points in the valley bottoms of the headwater reaches. The highly erosive dynamic of this watershed provides ample sediment, and some of these bofedales are up to 30 m deep. Annual precipitation in the region is limited to 4-6 events annually that fall primarily as snow at elevations above 3500 m. The subsurface storage of the headwaters is limited by the steep terrain of the headwater catchments that are devoid of soils and primarily underlain by granite bedrock. Downstream, irrigated area has increased by 200% between 1985 and 2005, driven by the cultivation of table grapes for export. For over 70 years local water managers have flooded the bodfedales during spring runoff to augment late season flow when irrigation demand peaks. While this low-tech strategy has worked in the past, a recent 8-year drought has raised concerns over long-term water security. We apply geophysical and geographic measurements, water quality, and stable isotopic tracers to calculate the volume of water storage and residence times in the bofedales of Río Claro. This information will be used to evaluate the reliability of the bofedale system as compared to a proposed reservoir in the headwaters of the Río Claro. Additionally, estimating the storage and residence times of the will help reduce uncertainty for modeling efforts currently underway in Río Claro.

  20. Should we plant trees to offset greenhouse gas emissions in semi-arid environments?

    Science.gov (United States)

    Pataki, D. E.; Pincetl, S.; Gillespie, T. W.; Li, W.; McCarthy, H. R.; Saatchi, S.; Saphores, J.

    2008-12-01

    Urban tree planting programs have been gaining popularity in the United States. Urban trees have been associated with a variety of environmental benefits, including improvements in air quality, mitigation of urban heat island effects, reductions in stormwater runoff, and more recently, carbon sequestration. There are also other potential aesthetic and economic benefits of urban forests, which have been shown to affect real estate values. However, there may also be significant economic and environmental costs of planting and maintaining trees in urban areas, particularly in semi-arid environments where trees are not native and require irrigation and fertilization. We are conducting an analysis of the Million Tree Initiative in the city of Los Angeles, which has committed to a major tree planting program. Los Angeles currently has a low tree canopy cover relative to other cities, particularly in its low income neighborhoods. We are evaluating the decision-making processes associated with the new tree planting program, its perceived benefits, and its actual benefits based on measurements of plant and ecosystem processes such as transpiration, photosynthesis, and water use efficiency; remote sensing analyses of tree cover and surface temperature; and economic analyses. We have found great variability in the interpretation of the program by its various participants, but also significant institutional learning as the program has evolved. Our datasets have challenged some of the common assumptions of the program, for example, the assumption that native species use less water than imported species and are therefore more environmentally beneficial in terms of water resources. We have also found significant impacts of the urban forest on air temperature, which may reduce energy use during the summer due to reductions in air conditioning. This is likely to be a larger effect of urban trees on greenhouse gas emissions than direct carbon sequestration alone, which is a very

  1. Untangling the biological contributions to soil stability in semiarid shrublands

    Science.gov (United States)

    Chaudhary, V. Bala; Bowker, Matthew A.; O'Dell, Thomas E.; Grace, James B.; Redman, Andrea E.; Rillig, Matthias C.; Johnson, Nancy C.

    2009-01-01

    Communities of plants, biological soil crusts (BSCs), and arbuscular mycorrhizal (AM) fungi are known to influence soil stability individually, but their relative contributions, interactions, and combined effects are not well understood, particularly in arid and semiarid ecosystems. In a landscape-scale field study we quantified plant, BSC, and AM fungal communities at 216 locations along a gradient of soil stability levels in southern Utah, USA. We used multivariate modeling to examine the relative influences of plants, BSCs, and AM fungi on surface and subsurface stability in a semiarid shrubland landscape. Models were found to be congruent with the data and explained 35% of the variation in surface stability and 54% of the variation in subsurface stability. The results support several tentative conclusions. While BSCs, plants, and AM fungi all contribute to surface stability, only plants and AM fungi contribute to subsurface stability. In both surface and subsurface models, the strongest contributions to soil stability are made by biological components of the system. Biological soil crust cover was found to have the strongest direct effect on surface soil stability (0.60; controlling for other factors). Surprisingly, AM fungi appeared to influence surface soil stability (0.37), even though they are not generally considered to exist in the top few millimeters of the soil. In the subsurface model, plant cover appeared to have the strongest direct influence on soil stability (0.42); in both models, results indicate that plant cover influences soil stability both directly (controlling for other factors) and indirectly through influences on other organisms. Soil organic matter was not found to have a direct contribution to surface or subsurface stability in this system. The relative influence of AM fungi on soil stability in these semiarid shrublands was similar to that reported for a mesic tallgrass prairie. Estimates of effects that BSCs, plants, and AM fungi have

  2. Cosmic Reason of Great Glaciation

    Science.gov (United States)

    Bagrov, Alexander; Murtazov, Andrey

    The origin of long-time and global glaciations in the past of our planet, which have been named «great», is still not clear. Both the advance of glaciers and their subsequent melting must be connected with some energy consuming processes. There is a powerful energy source permanently functioning throughout the Earth’s history - the solar radiation. The equality of the incoming shortwave solar energy and the transformed long-wave energy emitted by the Earth provides for the whole ecosphere’s sustainable evolution. Great glaciations might be caused by space body falls into the world oceans. If the body is large enough, it can stir waters down to the bottom. The world waters are part of the global heat transfer from the planet’s equator to its poles (nowadays, mostly to the North Pole). The mixing of the bottom and surface waters breaks the circulation of flows and they stop. The termination of heat transfer to the poles will result in an icecap at high latitudes which in its turn will decrease the total solar heat inflow to the planet and shift the pole ice boarder to the equator. This positive feedback may last long and result in long-time glaciations. The oceanic currents will remain only near the equator. The factor obstructing the global cooling is the greenhouse effect. Volcanic eruptions supply a lot of carbon dioxide into the atmosphere. When due to the increased albedo the planet receives less solar heat, plants bind less carbon oxide into biomass and more of it retains in the atmosphere. Therefore, the outflow of heat from the planet decreases and glaciations does not involve the whole planet. The balance established between the heat inflow and heat losses is unstable. Any imbalance acts as a positive feed-back factor. If the volcanic activity grows, the inflow of the carbon dioxide into the atmosphere will cause its heating-up (plants will fail to reproduce themselves quickly enough to utilize the carbonic acid). The temperature growth will lead to

  3. What Caused the Great Depression?

    Science.gov (United States)

    Caldwell, Jean; O'Driscoll, Timothy G.

    2007-01-01

    Economists and historians have struggled for almost 80 years to account for the American Great Depression, which began in 1929 and lasted until the early years of World War II. In this article, the authors discuss three major schools of thought on the causes of the Great Depression and the long failure of the American economy to return to full…

  4. Conserving the Brazilian semiarid (Caatinga) biome under climate change

    DEFF Research Database (Denmark)

    Oliveira, Guilherme de; Bastos Araujo, Miguel; Rangel, Thiago Fernado

    2012-01-01

    to assess changes in climate suitability across individual species ranges, ensemble forecasting was used based on seven bioclimatic envelope models, three atmosphere–ocean general circulation models, and two greenhouse emission gas scenarios for 2020, 2050, and 2080. We found that most species will gain...... additional threats to the biome’s biodiversity. Here, we ask if the remnants of natural vegetation in Caatinga biome, where endemic terrestrial vertebrate species occur, are likely to retain more climatic suitability under climate change scenarios than other less pristine areas of the biome. In order......The Caatinga is a semiarid biome of the northeast of Brazil with only 1 % of its territory currently conserved. The biome’s biodiversity is highly threatened due to exposure to land conversion for agricultural and cattle ranch. Climate forecasts predict increases in aridity, which could pose...

  5. Water quality issues associated with agricultural drainage in semiarid regions

    Science.gov (United States)

    Sylvester, Marc A.

    High incidences of mortality, birth defects, and reproductive failure in waterfowl using Kesterson Reservoir in the San Joaquin Valley, Calif., have occurred because of the bioaccumulation of selenium from irrigation drainage. These circumstances have prompted concern about the quality of agriculture drainage and its potential effects on human health, fish and wildlife, and beneficial uses of water. The U.S. Geological Survey (USGS) and Lawrence Berkeley Laboratory, University of California (Berkeley, Calif.) organized a 1-day session at the 1986 AGU Fall Meeting in San Francisco, Calif., to provide an interdisciplinary forum for hydrologists, geochemists, and aquatic chemists to discuss the processes controlling the distribution, mobilization, transport, and fate of trace elements in source rocks, soils, water, and biota in semiarid regions in which irrigated agriculture occurs. The focus of t h e session was the presentation of research results on the source, distribution, movement, and fate of selenium in agricultural drainage.

  6. Wind Erosion Induced Soil Degradation in Northern China: Status, Measures and Perspective

    Directory of Open Access Journals (Sweden)

    Zhongling Guo

    2014-12-01

    Full Text Available Soil degradation is one of the most serious ecological problems in the world. In arid and semi-arid northern China, soil degradation predominantly arises from wind erosion. Trends in soil degradation caused by wind erosion in northern China frequently change with human activities and climatic change. To decrease soil loss by wind erosion and enhance local ecosystems, the Chinese government has been encouraging residents to reduce wind-induced soil degradation through a series of national policies and several ecological projects, such as the Natural Forest Protection Program, the National Action Program to Combat Desertification, the “Three Norths” Shelter Forest System, the Beijing-Tianjin Sand Source Control Engineering Project, and the Grain for Green Project. All these were implemented a number of decades ago, and have thus created many land management practices and control techniques across different landscapes. These measures include conservation tillage, windbreak networks, checkerboard barriers, the Non-Watering and Tube-Protecting Planting Technique, afforestation, grassland enclosures, etc. As a result, the aeolian degradation of land has been controlled in many regions of arid and semiarid northern China. However, the challenge of mitigating and further reversing soil degradation caused by wind erosion still remains.

  7. Direct Seeding of Pinus halepensis Mill. for Recovery of Burned Semi-Arid Forests: Implications for Post-Fire Management for Improving Natural Regeneration

    Directory of Open Access Journals (Sweden)

    Francisco Antonio García-Morote

    2017-09-01

    Full Text Available Background: In order to maximize the resiliency of Pinus halepensis in semiarid forests, we analyzed direct seeding methods to recover burned stands by simulating post-fire soil treatments. Methods: Seeding was done by installing spot seeding (100 seeds in a 50 × 50 cm plot, using five methods: (1 covering seeding with wood chips; (2 seeding in branch piles; (3 seeding along trunks on contour-felled logs (on the shaded side; (4 seeding next to grass (Stipa tenacissima; and (5 seeding on the bare ground (control. The experiment was replicated according to aspect (northern and southern aspects. The response variables were seed germination (%, and seedling survival after the summer (measured in autumn 2015 and 2016. Direct seeding was carried out in 32 plots with 160-spot seeding, and data were analyzed using general linear models, including nested random effects. Results: Wood chips as a surface-covering material represented the only treatment that significantly improved seed germination and seedling survival (by 12.4%, and 17.4 seedlings m−2 in year 2, respectively compared with the control in the two topographic aspects. Conclusions: Covering seeding with wood chips, and thus chipping wood within the burned stand, form a recommended post-fire treatment to improve regeneration in Pinus halepensis semiarid stands.

  8. Semiarid ethnoagroforestry management: Tajos in the Sierra Gorda, Guanajuato, Mexico.

    Science.gov (United States)

    Hoogesteger van Dijk, Vincent M; Casas, Alejandro; Moreno-Calles, Ana Isabel

    2017-06-12

    The semi-arid environments harbor nearly 40% of biodiversity, and half of indigenous cultures of Mexico. Thousands of communities settled in these areas depend on agriculture and using wild biodiversity for their subsistence. Water, soil, and biodiversity management strategies are therefore crucial for people's life. The tajos, from Sierra Gorda, are important, poorly studied, biocultural systems established in narrow, arid alluvial valleys. The systems are constructed with stone-walls for capturing sediments, gradually creating fertile soils in terraces suitable for agriculture in places where it would not be possible. We analyzed biocultural, ecological, economic and technological relevance of the artificial oasis-like tajos, hypothesizing their high capacity for maintaining agricultural and wild biodiversity while providing resources to people. We conducted our research in three sections of the Mezquital-Xichú River, in three communities of Guanajuato, Mexico. Agroforestry management practices were documented through semi-structured and in-depth qualitative interviews. Vegetation composition of local forests and that maintained in tajos was sampled and compared. Tajos harbor high agrobiodiversity, including native varieties of maize and beans, seven secondary crops, 47 native and 25 introduced perennial plant species. Perennial plants cover on average 26.8% of the total surface of plots. Tajos provide nearly 70% of the products required by households' subsistence and are part of their cultural identity. Tajos are heritage of TEK and land management forms of pre-Columbian Mexican and Mediterranean agricultural techniques, adapting and integrating modern agricultural practices. Tajos are valuable biocultural systems adapted to local semiarid conditions and sources of technology for similar areas of the World.

  9. The 2009 Samoa-Tonga great earthquake triggered doublet

    Science.gov (United States)

    Lay, T.; Ammon, C.J.; Kanamori, H.; Rivera, L.; Koper, K.D.; Hutko, Alexander R.

    2010-01-01

    Great earthquakes (having seismic magnitudes of at least 8) usually involve abrupt sliding of rock masses at a boundary between tectonic plates. Such interplate ruptures produce dynamic and static stress changes that can activate nearby intraplate aftershocks, as is commonly observed in the trench-slope region seaward of a great subduction zone thrust event1-4. The earthquake sequence addressed here involves a rare instance in which a great trench-slope intraplate earthquake triggered extensive interplate faulting, reversing the typical pattern and broadly expanding the seismic and tsunami hazard. On 29 September 2009, within two minutes of the initiation of a normal faulting event with moment magnitude 8.1 in the outer trench-slope at the northern end of the Tonga subduction zone, two major interplate underthrusting subevents (both with moment magnitude 7.8), with total moment equal to a second great earthquake of moment magnitude 8.0, ruptured the nearby subduction zone megathrust. The collective faulting produced tsunami waves with localized regions of about 12metres run-up that claimed 192 lives in Samoa, American Samoa and Tonga. Overlap of the seismic signals obscured the fact that distinct faults separated by more than 50km had ruptured with different geometries, with the triggered thrust faulting only being revealed by detailed seismic wave analyses. Extensive interplate and intraplate aftershock activity was activated over a large region of the northern Tonga subduction zone. ?? 2010 Macmillan Publishers Limited. All rights reserved.

  10. Karst characterization in a semi-arid region using gravity, seismic, and resistivity geophysical techniques.

    Energy Technology Data Exchange (ETDEWEB)

    Barnhart, Kevin Scott

    2013-10-01

    We proposed to customize emerging in situ geophysical monitoring technology to generate time-series data during sporadic rain events in a semi-arid region. Electrodes were to be connected to wireless \

  11. An Overview of Biodegradation of LNAPLs in Coastal (Semi)-arid Environment.

    KAUST Repository

    Yadav, Brijesh Kumar; Hassanizadeh, S Majid

    2011-01-01

    environmental variables, and their remediation favoring customization requires a sound understanding of their integrated behavior on fate and transport of LNAPLs under site-specific conditions. The arid and semi-arid coastal sites are characterized by specific

  12. Canopy management and water use efficiency in vineyards under Mediterranean semiarid conditions

    Directory of Open Access Journals (Sweden)

    de la Fuente Mario

    2015-01-01

    In addition, both positive effects of sprawl treatments (crop load and training system resulted in better yield and quality in Mediterranean semiarid conditions under the same inputs (sun, water and soil, causing higher efficiency of natural resources.

  13. Financial costs of ecologically nonsustainable farming practices in a semiarid system

    CSIR Research Space (South Africa)

    Herling, MC

    2009-11-01

    Full Text Available Nonsustainable ostrich farming practices have degraded large areas of the Little Karoo, a semiarid region in South Africa. The Little Karoo lies within the Succulent Karoo biome, a recognized biodiversity hotspot. A financial feasibility analysis...

  14. Geothermal conditions in Northern Switzerland

    International Nuclear Information System (INIS)

    Rybach, L.; Eugster, W.; Griesser, J.C.

    1987-01-01

    The geothermal field in northern Switzerland, derived from a great number of borehole temperature measurements, is characterized by a strongly positive temperature gradient and heat flow anomaly (>150 mW/m 2 ) in the lower Aare valley. The anomaly is centered above the recently discovered Permocarboniferous trough. Several possibilities to explain the anomaly (thermal disturbance in the mantle, cooling shallow intrusion, locally strong uplift/erosion, local contrasts in petrophysical properties) can be ruled out on the basis of model calculations. Uprising deep groundwater is favoured as the mechanism creating the observed anomaly. Deep groundwater circulation was investigated in detail, especially to clarify the hydraulic role of the Permocarboniferous trough, by coupled thermo-hydraulic modelling, using the integrated finite difference technique. The model was carefully validated by field data. The results reveal the draining effect of the Permocarboniferous trough and indicate that vertical permeability is present in the vicinity of the trough even at depths of several kilometers. They further imply that large parts of the crystalline basement in northern Switzerland have average hydraulic conductivities >10 -9 m/sec and that Darcy velocities in the order of 10 mm/year must be expected. (author) 24 refs., 4 figs., 1 tab

  15. Development and implementation of a monitoring and information system to increase water use efficiency in arid and semi-arid areas in Limarí, Central Chile (WEIN

    Directory of Open Access Journals (Sweden)

    E. Berger

    2016-10-01

    Full Text Available The project WEIN was funded by the Federal Ministry of Education and Research (BMBF | Berlin, Germany in the framework of the high-tech strategy of Germany's program "KMU-Innovativ". The project started in 2012 and was completed in 2014. In the scope of the project, an integrated system for analysis, monitoring and information at river basin level was developed, which provides relevant information for all stakeholders that are concerned with water resource issues. The main objective of the project was to improve water use efficiency and hence ensure the agricultural production in the region. The pilot region, in which this system was implemented, is the semi-arid Limarí basin in Northern Central Chile. One of the main parts of the project was the development and implementation of a web- and app-based irrigation water ordering and accounting system for local farmers.

  16. Great Lakes Environmental Research Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — NOAA-GLERL and its partners conduct innovative research on the dynamic environments and ecosystems of the Great Lakes and coastal regions to provide information for...

  17. What Caused the Great Recession?

    OpenAIRE

    Homburg, Stefan

    2014-01-01

    This paper examines five possible explanations for the Great Recession of 2008 and 2009, using data for the United States and the eurozone. Of these five hypotheses, four are not supported by the data, while the fifth appears reasonable.

  18. Arthroscopy of the great toe

    NARCIS (Netherlands)

    Frey, C.; van Dijk, C. N.

    1999-01-01

    The few available reports of arthroscopic treatment of the first MTP joint in the literature indicate favorable outcome. However, arthroscopy of the great toe is an advanced technique and should only be undertaken by experienced surgeons

  19. Mapping Annual Forest Cover in Sub-Humid and Semi-Arid Regions through Analysis of Landsat and PALSAR Imagery

    Directory of Open Access Journals (Sweden)

    Yuanwei Qin

    2016-11-01

    Full Text Available Accurately mapping the spatial distribution of forests in sub-humid to semi-arid regions over time is important for forest management but a challenging task. Relatively large uncertainties still exist in the spatial distribution of forests and forest changes in the sub-humid and semi-arid regions. Numerous publications have used either optical or synthetic aperture radar (SAR remote sensing imagery, but the resultant forest cover maps often have large errors. In this study, we propose a pixel- and rule-based algorithm to identify and map annual forests from 2007 to 2010 in Oklahoma, USA, a transitional region with various climates and landscapes, using the integration of the L-band Advanced Land Observation Satellite (ALOS PALSAR Fine Beam Dual Polarization (FBD mosaic dataset and Landsat images. The overall accuracy and Kappa coefficient of the PALSAR/Landsat forest map were about 88.2% and 0.75 in 2010, with the user and producer accuracy about 93.4% and 75.7%, based on the 3270 random ground plots collected in 2012 and 2013. Compared with the forest products from Japan Aerospace Exploration Agency (JAXA, National Land Cover Database (NLCD, Oklahoma Ecological Systems Map (OKESM and Oklahoma Forest Resource Assessment (OKFRA, the PALSAR/Landsat forest map showed great improvement. The area of the PALSAR/Landsat forest was about 40,149 km2 in 2010, which was close to the area from OKFRA (40,468 km2, but much larger than those from JAXA (32,403 km2 and NLCD (37,628 km2. We analyzed annual forest cover dynamics, and the results show extensive forest cover loss (2761 km2, 6.9% of the total forest area in 2010 and gain (3630 km2, 9.0% in southeast and central Oklahoma, and the total area of forests increased by 684 km2 from 2007 to 2010. This study clearly demonstrates the potential of data fusion between PALSAR and Landsat images for mapping annual forest cover dynamics in sub-humid to semi-arid regions, and the resultant forest maps would be

  20. Simulating the impact of no-till systems on field water fluxes and maize productivity under semi-arid conditions

    Science.gov (United States)

    Mupangwa, W.; Jewitt, G. P. W.

    NT systems may have great potential for reducing surface runoff from smallholder fields and that the NT systems may have potential to recharge groundwater resources through increased deep drainage. However, it was also noted that the APSIM model has major shortcomings in simulating the water balance at this level of detail and that the findings need to be confirmed by further field based and modelling studies. Nevertheless, it is clear that without mulch or a cover crop, the continued high soil evaporation and correspondingly low crop yields suggest that there is little benefit to farmers adopting NT systems in semiarid environments, despite potential water resources benefits downstream. In such cases, the potential for payment for ecosystem services should be explored.

  1. Modeled Impacts of Chronic Wasting Disease on White-Tailed Deer in a Semi-Arid Environment.

    Directory of Open Access Journals (Sweden)

    Aaron M Foley

    adult survivorship to buffer the low and erratic fawn recruitment rates. The increase in additive mortality rates for adults via CWD negatively impacted simulated population trends to the extent that hunter opportunity would be greatly reduced. Our results improve understanding of the potential influences of CWD on deer populations in semi-arid environments with implications for deer managers, disease ecologists, and policy makers.

  2. The Sixth Great Mass Extinction

    Science.gov (United States)

    Wagler, Ron

    2012-01-01

    Five past great mass extinctions have occurred during Earth's history. Humanity is currently in the midst of a sixth, human-induced great mass extinction of plant and animal life (e.g., Alroy 2008; Jackson 2008; Lewis 2006; McDaniel and Borton 2002; Rockstrom et al. 2009; Rohr et al. 2008; Steffen, Crutzen, and McNeill 2007; Thomas et al. 2004;…

  3. Rapid warming accelerates tree growth decline in semi-arid forests of Inner Asia.

    Science.gov (United States)

    Liu, Hongyan; Park Williams, A; Allen, Craig D; Guo, Dali; Wu, Xiuchen; Anenkhonov, Oleg A; Liang, Eryuan; Sandanov, Denis V; Yin, Yi; Qi, Zhaohuan; Badmaeva, Natalya K

    2013-08-01

    Forests around the world are subject to risk of high rates of tree growth decline and increased tree mortality from combinations of climate warming and drought, notably in semi-arid settings. Here, we assess how climate warming has affected tree growth in one of the world's most extensive zones of semi-arid forests, in Inner Asia, a region where lack of data limits our understanding of how climate change may impact forests. We show that pervasive tree growth declines since 1994 in Inner Asia have been confined to semi-arid forests, where growing season water stress has been rising due to warming-induced increases in atmospheric moisture demand. A causal link between increasing drought and declining growth at semi-arid sites is corroborated by correlation analyses comparing annual climate data to records of tree-ring widths. These ring-width records tend to be substantially more sensitive to drought variability at semi-arid sites than at semi-humid sites. Fire occurrence and insect/pathogen attacks have increased in tandem with the most recent (2007-2009) documented episode of tree mortality. If warming in Inner Asia continues, further increases in forest stress and tree mortality could be expected, potentially driving the eventual regional loss of current semi-arid forests. © 2013 John Wiley & Sons Ltd.

  4. Coastal Wetland Ecosystem Responses to Climate Change: the Role of Macroclimatic Drivers along the Northern Gulf of Mexico

    Science.gov (United States)

    Osland, M. J.; Enwright, N.; Day, R. H.; Gabler, C. A.; Stagg, C. L.; From, A. S.

    2014-12-01

    Across the globe, macroclimatic drivers greatly influence coastal wetland ecosystem structure and function. However, changing macroclimatic conditions are rarely incorporated into coastal wetland vulnerability assessments. Here, we quantify the influence of macroclimatic drivers upon coastal wetland ecosystems along the Northern Gulf of Mexico (NGOM) coast. From a global perspective, the NGOM coast provides several excellent opportunities to examine the effects of climate change upon coastal wetlands. The abundant coastal wetland ecosystems in the region span two major climatic gradients: (1) a winter temperature gradient that crosses temperate to tropical climatic zones; and (2) a precipitation gradient that crosses humid to semi-arid zones. We present analyses where we used geospatial data (historical climate, hydrology, and coastal wetland coverage) and field data (soil, elevation, and plant community composition and structure) to quantify climate-mediated ecological transitions. We identified winter climate and precipitation-based thresholds that separate mangrove forests from salt marshes and vegetated wetlands from unvegetated wetlands, respectively. We used simple distribution and abundance models to evaluate the potential ecological effects of alternative future climate change scenarios. Our results illustrate and quantify the importance of macroclimatic drivers and indicate that climate change could result in landscape-scale changes in coastal wetland ecosystem structure and function. These macroclimate-mediated ecological changes could affect the supply of some ecosystem goods and services as well as the resilience of these ecosystems to stressors, including accelerated sea level rise. Collectively, our findings highlight the importance of incorporating macroclimatic drivers within future-focused coastal wetland vulnerability assessments.

  5. Vulnerability Assessment of the Livelihoods in Tanzania’s Semi-Arid Agro-Ecological Zone under Climate Change Scenarios

    Directory of Open Access Journals (Sweden)

    Msafiri Y. Mkonda

    2018-04-01

    Full Text Available Despite the established literature on the vulnerability to climate change in various parts of Tanzania, it is worthwhile to assess the extent of this vulnerability of the peoples’ livelihoods and predict its future outcome. This is particularly important in the vulnerable ecosystems, that is, the semi-arid zones of Tanzania where the people’s livelihoods are highly attached to the declining local condition. The present study aims to assess the livelihoods vulnerability in Kongwa District, the semi-arid zone of Central Tanzania. In doing so, a wide range of methods were employed during data collection and analyses including surveys, informative interviews, discussions and observation. The study sampled 400 (≤10% respondents during a survey. The Mann-Kendall Test with SPSS V20, Microsoft Excel and Theme content techniques were used for data analyses. The results indicate that climate stress has adversely impacted the quality of soil, vegetation, crop yields and intensified environmental degradation. Since most people depend upon the mentioned affected aspects, it is expected that also the level of livelihood vulnerability has elevated. Further, this situation has greatly contributed to increased poverty and thus, propagates the “tragedy of the common” to the available environmental resources. As a response to increased vulnerability, some farmers have abandoned thousands of hectares of agricultural farms that seemed to be less productive. Despite this, slight measures have been taken by both the government and other key stakeholders to limit vulnerability. The findings of this study provide a theoretical and practical basis for coordinating a sustainable man-environment relationship, ensuring the sustainability of the environment which is the major source of peoples’ livelihoods.

  6. Constraining water uptake depths in semiarid environments using water stable isotopes

    Science.gov (United States)

    Beyer, Matthias; Königer, Paul; Himmelsbach, Thomas

    2017-04-01

    The biophysical process of transpiration recently received increased attention by ecohydrologists as it has been proven the largest flux of the global water balance. However, fundamental aspects related to the questions how and from which sources plants receive their water are not fully understood. Especially the process of plant water uptake from deeper soil and its impact on the water balance requires increased scientific effort. In this study we combined tracer experiments with the analysis of natural isotopic compositions in order to: i) derive a suitable site-specific root water uptake distribution for hydrological modeling; ii) find indicators for groundwater use by specific plants; and iii) evaluate the importance of deep unsaturated zone water uptake using HYDRUS 1D. The bayesian mixing model MixSIAR was applied at a semiarid site with a deep unsaturated zone in northern Namibia in order to identify source water contributions of the most abundant species (A.erioloba, B.plurijuga, C.collinum, S.luebertii and T.sericea). In addition, a previously developed method for the investigation of root water uptake depths based on deuterium labeling (2H2O) at specific depths (0.5 to 4 m) and monitoring of tracer uptake by plants was carried out with a focus on the deeper unsaturated zone. With the experimental results a root water uptake distribution for the lateral root zone was derived which allows to constrain the source water contributions estimated with MixSIAR. Finally, a HYDRUS 1D model was established and unsaturated zone water transport was evaluated. The analysis of the natural isotopic compositions reveals a significant contribution of groundwater (median: 48%) to the isotopic composition of A.erioloba at the end of the dry season indicating the presence of deep tap roots for a number of individuals. All other investigated species obtain their water from the shallow (median: 22%) or deeper (median: 62%) unsaturated zone at this time of the year. The water

  7. Northern Dimension: Participant Strategies

    Directory of Open Access Journals (Sweden)

    Busygina Irina

    2009-03-01

    Full Text Available This article is devoted to the “Northern Dimension” initiative of the EU which also includes North-West Russia, Norway and Iceland. It is noted that the “Northern Dimension” in the theoretical perspective can be considered as part of strategic multi-level interactions between member-states of the EU and Russia. On this basis, the authors analyze implications and effects of the strategic interdependence of all the EU-Russia relation levels.

  8. Northern Dimension: Participant Strategies

    Directory of Open Access Journals (Sweden)

    Busygina I.

    2009-01-01

    Full Text Available his article is devoted to the “Northern Dimension” initiative of the EU which also includes North-West Russia, Norway and Iceland. It is noted that the “Northern Dimension” in the theoretical perspective can be considered as part of strategic multi-level interactions between member-states of the EU and Russia. On this basis, the authors analyze implications and effects of the strategic interdependence of all the EU-Russia relation levels.

  9. Strategic Framework for Sustainable Management of Drainage Systems in Semi-Arid Cities: An Iraqi Case Study

    Directory of Open Access Journals (Sweden)

    Mohammed Nanekely

    2016-09-01

    Full Text Available For the purpose of this paper, Erbil city, located in the northern part of Iraq, has been chosen as a representative case study for a large number of cities, particularly in semi-arid areas, lacking sustainable drainage systems (SuDS. The study assesses (a the role of SuDS as a measure in areas with a water shortage; (b water scarcity in decision-making processes; (c the lack of legislation to implement SuDS; (d the adverse effects of climate change on the urban drainage system; and (e the effects of an increased population on SuDS implementation. An integrated methodology that incorporates a self-administrated questionnaire, workshops, face-to-face communication and interviews, as well as electronic media interactions, were used to achieve the objectives. A generic platform that consists of thirteen pillars, supporting the short to long-term national policies and strategies towards a sustainable urban drainage system, has been developed. Results showed that environmental laws need to be introduced. Findings also indicate that a growing population, which is partly due to an increase of internally displaced people, is a major challenge to an early application of SuDS, due to a rise in land demand and a lack of financial resources.

  10. Landscape Characteristics and Variations in Longitudinal Stream Flow Contribution in two Headwater Semi-Arid Mountain Watersheds

    Science.gov (United States)

    Shakespeare, B.; Gooseff, M. N.

    2005-12-01

    Understanding what role particular catchment attributes (slope, aspect, landcover, and contributing area) play in the contribution of stream flow is important for land management decisions, especially in the semi-arid western areas of the United States. Our study site is paired small catchments (approximately 9 and 11 km2) in the headwaters of the Weber drainage basin in Northern Utah. These catchments are surrounded by Wasatch formation with loamy textured soils. One catchment is predominantly underlain by quartzite while the other catchment is mostly underlain by limestone. We measured lateral flow gains every 200 to 400 meters using salt dilution gauging techniques throughout the ~5 km long streams. These measurements were taken synoptically 3 times during the seasonal discharge recession (summer 2005). The flows ranged spatially from 4 L s-1 to 55 L s-1 and varied temporally by as much as 50% when comparing the same reaches. Using GIS software, landscape analysis of slope, aspect, contributing area, topographic convergence, riparian and hillslope area, and landcover was performed for each of the delineated stream reach contributing areas. The results were tested for correlations between lateral flow gains measured in the field and different landscape characteristics. Each of the synoptic events was compared with each other to explore effects of seasonal recession on the relationships between flow gain and landscape characteristics.

  11. Has contemporary climate change played a role in population declines of the lizard Ctenophorus decresii from semi-arid Australia?

    Science.gov (United States)

    Walker, Samantha; Stuart-Fox, Devi; Kearney, Michael R

    2015-12-01

    Whilst contemporary climatic changes are small in magnitude compared to those predicted for the coming decades, they have already been linked to species range shifts and local extinctions. Elucidating the drivers behind species' responses to contemporary climate change will better inform management strategies for vulnerable and pest species alike. A recent proposal to explain worldwide local extinctions in lizards is that increasing maximum temperatures have constrained lizard activity time in the breeding season beyond extinction thresholds. Here we document a significant population decline and potential local extinction at the warm (northern) range margin of the tawny dragon, Ctenophorus decresii, a rock-dwelling lizard from the Flinders Ranges in semi-arid Australia. We developed and tested a biophysical model of tawny dragon thermoregulatory behaviour and drove the model with daily weather data for the period 1990-2009 across the Flinders Ranges. Our results indicate that potential annual activity time has likely increased over this period throughout the historic range, with within-season declines only in the summer months at the northern range limit. However, populations that have declined since 2000 have also likely experienced higher active body temperatures and more stringent retreat-site requirements (deeper crevices) than have regions where the species remains common, during a period of declining rainfall. Our laboratory estimates of thermal preference in this species were insensitive to altered nutritional and hydric state. Thus it is possible that recent population declines are linked to desiccation stress driven by higher body temperatures and declining rainfall. Our study illustrates that simple indices of the impact of climate warming on animals, such as activity restriction, may in fact reflect a variety of potential mechanisms whose ultimate outcome will be contingent on other factors such as water and shelter availability. Copyright © 2014

  12. Co-evolution of Vegetation, Sediment Transport and Infiltration on semi-arid hillslopes

    Science.gov (United States)

    Harman, C. J.; Troch, P. A.; Lohse, K. A.; Sivapalan, M.

    2011-12-01

    Soils in semi-arid landscapes can vary over very small distances, with a great deal of variation associated with 'resource islands' created and maintained by woody vegetation. The distinct physical and hydraulic properties that arise in these islands can lead to spatial patterns of infiltration that have been implicated in the maintenance of the vegetation populating the island. Less well understood are the roles that the small-scale variability in soils plays in determining the transport of sediments, water and sediment-bound carbon and nitrogen across hillslopes. Here we explore these relationships using a coupled field and modeling approach. Detailed field data from hillslopes underlain by both granite and schist parent materials in the Santa Catalina mountains (part of the JSC Critical Zone Observatory) suggest that soils under individual velvet mesquite (latin name) contain higher concentration of soil organic matter and have higher hydraulic conductivity and water holding capacity. Greater infiltration and increased roughness under the canopy appears to lead to the formation of mounds that alter overland flow lines around the area under the canopy, particularly in the finer schist soils. This diversion leads to a complex distribution of shear stresses across the hillslope, creating systematic patterns in the transport of carbon and nitrogen rich soils under the canopies. The relationship between the small scale mechanism and the emergent pattern dynamics in the temporal variability of materials delivered to the stream from the hillslope are also examined, and the implications of these results for the modeling of water, sediment and nutrient fluxes at hillslope scales will be discussed.

  13. QUALITY OF IRRIGATED APPLES IN THE SEMIARID REGION OF THE NORTHEAST OF BRAZIL

    Directory of Open Access Journals (Sweden)

    CÍNTIA PATRÍCIA MARTINS DE OLIVEIRA

    2017-01-01

    Full Text Available The great solar radiation in the Brazilian semiarid region, combined with an adequate irrigation management, favors fruit production and quality of crops that were adapted to this region. The objective of this work was to evaluate the fruit quality of two apple cultivars grown in the Sub-Mid São Francisco River Valley under different irrigation water depths. A complete randomized block experimental design in a split -plot arrangement with five replications was used. The plots consisted of four irrigation water depths (ID (60, 80, 100 and 120% of the reference evapotranspiration - ETo, the subplots consisted of two apple cultivars (C (Julieta and Princesa and the sub-subplots consisted of fruit positions in the tree canopies (FP (east and west sides. The soluble solids content (SS, titratable acidity (TA, SS/TA ratio, pulp firmness (PF and fresh weight (FW of the fruits were evaluated. The factors evaluated showed no triple interaction between the evaluated factors, however, the SS and TA were significantly affected by them; the interaction between ID and C significantly affected the PF; the interaction between ID and FP significantly affected the PF, SS/TA ratio and FW; and the interaction between C and FP significantly affected the SS/TA ratio. The increase in water depth increased the fruit size of both cultivars, without compromising the post-harvest quality. The cultivar Princesa presented the best results regarding SS, TA, PF and FW, however, both cultivars had organoleptic characteristics within the recommended standards for commercialization. The fruits harvested on the west side presented better post-harvest quality.

  14. The Great Pratfall of China

    Institute of Scientific and Technical Information of China (English)

    Tyler; Roney

    2013-01-01

    With China on its way out of the dark as spring gets into swing,we feel the Northern Hemisphere could use a bit of a chuckle.Liu Jue dug through annals of clowns,tricksters and fools to shed some light on the history of jesters in China with'Don’t Pity the Fool.'encompassing thousands of years of these lowly entertainers who could once speak truth to power.From derisive dwarfs to mordant musicians,the Chinese fool hits on all sides of history,with stories of brave men harassing their emperors with sarcasm and cutting parody for the public good.

  15. [One year after the Great Tohoku Disaster].

    Science.gov (United States)

    Aoki, Masashi

    2012-01-01

    After the great earthquake of March 11, 2011, at least seven hospitals with 723 beds along the Miyagi Prefecture northern coastline were so devastated they could no longer function, leaving only several available hospitals. The two crucial issues thus became maintaining communications and regional transport. Phones and wireless were knocked out in most hospitals and areas. Many of the severe cases had to be brought to the Tohoku University Hospital at Sendai from the above the hospitals. Tohoku University Hospital and other medical facilities in the Tohoku district were in a terrible crisis of electricity shortage. It was a critical situation, particularly for patients with amyotrophic lateral sclerosis requiring artificial ventilation. We should hurry to submit a guideline for medical transportation for patients with neuromuscular diseases requiring artificial ventilation. We also should research the disaster medicine in the field of neurology, and prevent the neurological disease progressing after the earthquake. A large number of hospitals in coastal areas suffered devastating damage. We do not think it is feasible or even reasonable to restore such hospitals to what they were before the disaster. We started Tohoku Medical Megabank Organization as a disaster recovery model for revitalizing the areas reported to have scarce medical services. The project provides supports to local medical services, constructs a community coalition for medical information, sets up a biobank based on large-scale cohort studies, and provides educational training to produce highly specialized medical practitioners.

  16. RAINFALL CHARACTERIZATION AND SEDIMENTOLOGICAL RESPONSES OF WATERSHEDS WITH DIFFERENT LAND USES TO PRECIPITATION IN THE SEMIARID REGION OF BRAZIL

    Directory of Open Access Journals (Sweden)

    JACQUES CARVALHO RIBEIRO FILHO

    2017-01-01

    Full Text Available The objective of this work was to evaluated the precipitation characteristics (depth, I30 and erosivity and their effects on sediment production in three watersheds under different managements of land use 35 - year regenerating Caatinga (RC, thinned Caatinga (TC, which underwent thinning of trees with diameter smaller than 10 cm; and deforested Caatinga (followed by burning and pasture (DC. The experimente was conducted in the central, tropical semiarid region of the State of Ceará, Brazil. The precipitation events, surface runoff and sediment production were monitored from 2010 to 2015. The precipitation characteristics were subjected to Pearson's correlation at 1 and 5% of significance and the events that produced sediments in each watershed were hierarchically grouped by hierarchical cluster analysis technique. Two hundred precipitation events were recorded, with 23 (RC, 18 (TC and 43 (DC events producing sediments. The use of thinning (TC decreased the sediment production by 53.5%, while the deforestation, burn and pasture cultivation (DC increased soil losses by 14%, compared with the RC. The sediment production was greatly correlated with the I30 in the three watersheds, denoting the erosion process great dependence on the precipitation intensity.

  17. Famous puzzles of great mathematicians

    CERN Document Server

    Petković, Miodrag S

    2009-01-01

    This entertaining book presents a collection of 180 famous mathematical puzzles and intriguing elementary problems that great mathematicians have posed, discussed, and/or solved. The selected problems do not require advanced mathematics, making this book accessible to a variety of readers. Mathematical recreations offer a rich playground for both amateur and professional mathematicians. Believing that creative stimuli and aesthetic considerations are closely related, great mathematicians from ancient times to the present have always taken an interest in puzzles and diversions. The goal of this

  18. Source identification of fine-grained suspended sediment in the Kharaa River basin, northern Mongolia

    Energy Technology Data Exchange (ETDEWEB)

    Theuring, Philipp [Department of Aquatic Ecosystem Analysis and Management — ASAM, Helmholtz Centre for Environmental Research — UFZ, Brückstrasse 3a, D-39114 Magdeburg (Germany); Collins, Adrian L. [Sustainable Soils and Grassland Systems Department, Rothamsted Research, North Wyke, Okehampton, Devon EX20 2SB (United Kingdom); Rode, Michael [Department of Aquatic Ecosystem Analysis and Management — ASAM, Helmholtz Centre for Environmental Research — UFZ, Brückstrasse 3a, D-39114 Magdeburg (Germany)

    2015-09-01

    Fine sediment inputs into river systems can be a major source of nutrients and heavy metals and have a strong impact on water quality and ecosystem functions of rivers and lakes, including those in semiarid regions. However, little is known to date about the spatial distribution of sediment sources in most large scale river basins in Central Asia. Accordingly, a sediment source fingerprinting technique was used to assess the spatial sources of fine-grained (< 10 μm) sediment in the 15 000 km{sup 2} Kharaa River basin in northern Mongolia. Variation in geochemical composition (e.g. in Ti, Sn, Mo, Mn, As, Sr, B, U, Ca and Sb) was used for sediment source discrimination with geochemical composite fingerprints based on Genetic Algorithm (GA)-driven Discriminant Function Analysis, the Kruskal–Wallis H-test and Principal Component Analysis. All composite fingerprints yielded a satisfactory GOF (> 0.97) and were subsequently used for numerical mass balance modelling with uncertainty analysis. The contributions of the individual sub-catchment spatial sediment sources varied from 6.4% (the headwater sub-catchment of Sugnugur Gol) to 36.2% (the Kharaa II sub-catchment in the middle reaches of the study basin), generally showing higher contributions from the sub-catchments in the middle, rather than the upstream, portions of the study area. The importance of river bank erosion is shown to increase from upstream to midstream tributaries. The source tracing procedure provides results in reasonable accordance with previous findings in the study region and demonstrates the applicability and associated uncertainties of the approach for fine-grained sediment source investigation in large scale semi-arid catchments. - Highlights: • Applied statistical approach for selecting composite fingerprints in Mongolia. • Geochemical fingerprinting for the definition of source areas in semiarid catchment. • Test of applicability of sediment sourcing in large scale semi-arid catchments

  19. Distribution of Chironomidae in a semiarid intermittent river of Brazil.

    Science.gov (United States)

    Farias, R L; Carvalho, L K; Medeiros, E S F

    2012-12-01

    The effects of the intermittency of water flow on habitat structure and substrate composition have been reported to create a patch dynamics for the aquatic fauna, mostly for that associated with the substrate. This study aims to describe the spatial distribution of Chironomidae in an intermittent river of semiarid Brazil and to associate assemblage composition with environmental variables. Benthic invertebrates were sampled during the wet and dry seasons using a D-shaped net (40 cm wide and 250 μm mesh), and the Chironomidae were identified to genus level. The most abundant genera were Tanytarsus, Polypedilum, and Saetheria with important contributions of the genera Procladius, Aedokritus, and Dicrotendipes. Richness and density were not significantly different between the study sites, and multiple regression showed that the variation in richness and density explained by the environmental variables was significant only for substrate composition. The composition of genera showed significant spatial segregation across the study sites. Canonical Correspondence Analysis showed significant correspondence between Chironomidae composition and the environmental variables, with submerged vegetation, elevation, and leaf litter being important predictors of the Chironomidae fauna. This study showed that Chironomidae presented important spatial variation along the river and that this variation was substantially explained by environmental variables associated with the habitat structure and river hierarchy. We suggest that the observed spatial segregation in the fauna results in the high diversity of this group of organisms in intermittent streams.

  20. Efficiency of snake sampling methods in the Brazilian semiarid region.

    Science.gov (United States)

    Mesquita, Paula C M D; Passos, Daniel C; Cechin, Sonia Z

    2013-09-01

    The choice of sampling methods is a crucial step in every field survey in herpetology. In countries where time and financial support are limited, the choice of the methods is critical. The methods used to sample snakes often lack objective criteria, and the traditional methods have apparently been more important when making the choice. Consequently researches using not-standardized methods are frequently found in the literature. We have compared four commonly used methods for sampling snake assemblages in a semiarid area in Brazil. We compared the efficacy of each method based on the cost-benefit regarding the number of individuals and species captured, time, and financial investment. We found that pitfall traps were the less effective method in all aspects that were evaluated and it was not complementary to the other methods in terms of abundance of species and assemblage structure. We conclude that methods can only be considered complementary if they are standardized to the objectives of the study. The use of pitfall traps in short-term surveys of the snake fauna in areas with shrubby vegetation and stony soil is not recommended.

  1. Perceptions of termites in urban areas of semiarid Brazil

    Directory of Open Access Journals (Sweden)

    Maria Avany Bezerra Gusmão

    2014-07-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2014v27n4p117 Perception of termites in urban areas of semiarid Brazil. Termites are present in the daily life of most people, although they usually evoke a sense of strong dislike, especially in populations of urban areas. This study sought to analyze the perception of these insects in human populations in urban areas in the towns of Fagundes (A1 and Pocinhos (A2, in Paraíba state, Brazil. Semi-structured questionnaires were answered by 100 residents in these two areas, following both synchronic and diachronic situations. In spite of the fact that most of the interviewees (64% in A1 and 72% in A2 were able to identify termites by morphology and had knowledge of use for treating eight types of human diseases, very few understood their ecological roles in nature. Attempts to eliminate termites from human environments were linked to the popular belief that these animals are sources of bad luck. Twenty-two percent of the interviewees in A1 and 8% in A2 believe that termites are capable of doing damage or harm, of having a foul smell, and/or of containing pus.In this sense, academic studies are important because they can inform people of the ecological roles of termites in natural and urban environments, while demystifying the termite as an agent of fear and destruction.

  2. The Ecohydrologic Role of Coexistence and Competition in Semiarid Hillslopes

    Science.gov (United States)

    Soltanjalili, M. J.; Saco, P. M.; Willgoose, G. R.

    2015-12-01

    Through its influence on runoff and erosion-deposition processes, vegetation remarkably regulates different aspects of landscape dynamics. Here, the influence of different plant functional traits on the coexistence of different species in arid and semi-arid regions with patchy vegetation is investigated using an ecohydrology model. The model simulates coevolving changes in biomass patterns for two species, as well as overland flow and soil moisture dynamics. Vegetation patterns emerge as a result of facilitation (shading and infiltration) and competition mechanisms as well as varying seed dispersal strategies. The results show that the survival of only one species or the coexistence of both species not only strongly depends on environmental stresses, but also on differences in hillslope micro and macro topography. These vegetation patterns have very different hydrologic signatures and the potential to trigger remarkably different geomorphic responses. Based on these results we establish new hypothesis that will be used to further investigate the role of plant interspecific and intraspecific feedbacks on landscape coevolution processes.

  3. Making a Great First Impression

    Science.gov (United States)

    Evenson, Renee

    2007-01-01

    Managers and business owners often base hiring decisions on first impressions. That is why it is so important to teach students to make a great first impression--before they go on that first job interview. Managers do not have unrealistic expectations, they just want to hire people who they believe can develop into valuable employees. A nice…

  4. Great Basin paleoenvironmental studies project

    International Nuclear Information System (INIS)

    1993-01-01

    Project goals, project tasks, progress on tasks, and problems encountered are described and discussed for each of the studies that make up the Great Basin Paleoenvironmental Studies Project for Yucca Mountain. These studies are: Paleobotany, Paleofauna, Geomorphology, and Transportation. Budget summaries are also given for each of the studies and for the overall project

  5. The Great Books and Economics.

    Science.gov (United States)

    Hartley, James E.

    2001-01-01

    Describes an introductory economics course in which all of the reading material is drawn from the Great Books of Western Civilization. Explains the rationale and mechanics of the course. Includes an annotated course syllabus that details how the reading material relates to the lecture material. (RLH)

  6. Great tit hatchling sex ratios

    NARCIS (Netherlands)

    Lessells, C.M.; Mateman, A.C.; Visser, J.

    1996-01-01

    The sex of Great Tit Parus major nestlings was determined using PCR RAPDs. Because this technique requires minute amounts of DNA, chicks could be sampled soon (0-2d) after hatching, before any nestling mortality occurred. The proportion of males among 752 chicks hatching in 102 broods (98.9% of

  7. The Great Gatsby. [Lesson Plan].

    Science.gov (United States)

    Zelasko, Ken

    Based on F. Scott Fitzgerald's novel "The Great Gatsby," this lesson plan presents activities designed to help students understand that adapting part of a novel into a dramatic reading makes students more intimate with the author's intentions and craft; and that a part of a novel may lend itself to various oral interpretations. The main activity…

  8. Great Basin wildlife disease concerns

    Science.gov (United States)

    Russ Mason

    2008-01-01

    In the Great Basin, wildlife diseases have always represented a significant challenge to wildlife managers, agricultural production, and human health and safety. One of the first priorities of the U.S. Department of Agriculture, Division of Fish and Wildlife Services was Congressionally directed action to eradicate vectors for zoonotic disease, particularly rabies, in...

  9. Traditional and Local Knowledge Practices for Disaster Risk Reduction in Northern Ghana

    Directory of Open Access Journals (Sweden)

    Nsioh Macnight Ngwese

    2018-03-01

    Full Text Available In order to deal with recurrent disasters, like floods and droughts coupled with the limited adaptive capacity, in the semiarid regions of Northern Ghana, local communities have no choice but to apply traditional and local knowledge practices. This study seeks to identify such practices employed in selected rural communities in Northern Ghana and to investigate their effectiveness. Data were collected through key informant interviews, household questionnaire surveys, focus group discussions, and participant observations. The findings indicated that although diverse practices were applied to predict and manage local disaster events, skepticism prevailed among locals toward these practices regarding their effectiveness. Due to the lack of science-based tools and systems for disaster prediction and management, local communities continually depended on these knowledge systems and practices. Integrating local and traditional disaster risk reduction (DRR efforts into modern scientific knowledge should be encouraged in order to reduce the vulnerability of local communities to disasters with thorough effectiveness evaluation protocols.

  10. Recovery of microbial community structure and functioning after wildfire in semi-arid environments: optimising methods for monitoring and assessment

    Science.gov (United States)

    Muñoz-Rojas, Miriam; Martini, Dylan; Erickson, Todd; Merritt, David; Dixon, Kingsley

    2015-04-01

    Introduction In semi-arid areas such as northern Western Australia, wildfires are a natural part of the environment and many ecosystems in these landscapes have evolved and developed a strong relationship with fire. Soil microbial communities play a crucial role in ecosystem processes by regulating the cycling of nutrients via decomposition, mineralization, and immobilization processes. Thus, the structure (e.g. soil microbial biomass) and functioning (e.g. soil microbial activity) of microbial communities, as well as their changes after ecosystem disturbance, can be useful indicators of soil quality and health recovery. In this research, we assess the impacts of fire on soil microbial communities and their recovery in a biodiverse semi-arid environment of Western Australia (Pilbara region). New methods for determining soil microbial respiration as an indicator of microbial activity and soil health are also tested. Methodology Soil samples were collected from 10 similar ecosystems in the Pilbara with analogous native vegetation, but differing levels of post-fire disturbance (i.e. 3 months, 1 year, 5, 7 and 14 years after wildfire). Soil microbial activity was measured with the Solvita test which determines soil microbial respiration rate based on the measurement of the CO2 burst of a dry soil after it is moistened. Soils were dried and re-wetted and a CO2 probe was inserted before incubation at constant conditions of 25°C during 24 h. Measurements were taken with a digital mini spectrometer. Microbial (bacteria and fungi) biomass and community composition were measured by phospholipid fatty acid analysis (PLFA). Results Immediately after the fire (i.e. 3 months), soil microbial activity and microbial biomass are similar to 14 years 'undisturbed' levels (53.18±3.68 ppm CO2-CO and 14.07±0.65 mg kg-1, respectively). However, after the first year post-fire, with larger plant productivity, microbial biomass and microbial activity increase rapidly, peaking after 5

  11. Jojoba - a promising plant for the semi-arid regions. [North America, plants, seeds, oils, waxes, growth, cultivation, lubricants, guayule, mesquite

    Energy Technology Data Exchange (ETDEWEB)

    Yermanos, D.M.

    1979-01-01

    As a result of the world-wide concern for conservation of resources and for the development of new renewable resources a great deal of attention has been directed towards the development of jojoba as a potential new crop for semi-arid regions. Jojoba grows wild in the Southwestern U.S. and N. Mexico, in areas where the annual precipitation is 4''-15''. Under cultivation it appears to grow satisfactorily in areas of marginal soil fertility, high salinity and high atmospheric temperatures. It appears to have no major natural enemies and to be tolerant to chemical treatments, if they were to become necessary. It is perennial with an assumed life span in excess of 150 years. Jojoba seed has an average weight of about 0.5 grams per seed, and it contains a unique liquid wax which is a superior lubricant and a potential replacement of whale oil, obtained from the sperm whale, and endangered species. Thus, jojoba has a double appeal, first as a potential crop of semi-arid regions requiring low cultural and energy inputs and second as a source of a valuable commodity. It should be pointed out that a cheap and abundant source of lubricants will disappear when our stock of fossil fuels are exhausted and that none of our new sources of energy have lubricants as by-products. Finally, jojoba could be grown with other companion crops such as guayule or mesquite for more diversified farming.

  12. Northern Ireland gas industry

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R S [Belfast City Council Gas Dept.; Asquith, R S; Brown, J M; McKay, G

    1977-07-01

    Throughout Northern Ireland the production of town gas is derived from hydrocarbon feedstocks. In the larger undertakings in Northern Ireland the feedstock is light distillate; a light petroleum feedstock which is a crude gasoline comprised mainly of pentanes, reformed in catalytic plants. The remaining gas undertakings produce a liquefied petroleum gas (LPG)/air mixture using a mixture of either butane or propane and air. The individual gas units and the type of reforming feedstock are shown. A review of the oil-dependence of town gas and electricity production in Northern Ireland has been considered and is mainly responsible for the high fuel prices experienced in the community. A detailed description of the reforming process has been described, and considerable efforts have been made to optimize the process. In spite of substantial economic savings being made on the processing unit, the gas industry is very susceptible to the changes in oil prices which have escalated rapidly in recent years. The difference in gas prices between the United Kingdom and Northern Ireland indicates that North Sea gas would offer major economic benefits to the gas industry in Northern Ireland, which is operating at a substantial loss at the moment. The industrial concerns, which are dependent on gas and therefore paying high fuel costs, suffer in competition with outside companies. The injection of a moderately cheap natural gas supply to the community may encourage industrial expansion and provide work in a high unemployment area. Although substantial costs must be incurred in distribution pipelines and burner conversions if Northern Ireland changes to natural gas, there appears to be a strong case to introduce North Sea gas in the near future.

  13. The Changing Family in Northern Ireland: Young People and Divorce.

    Science.gov (United States)

    Fawcett, Margaret I.

    2000-01-01

    Interviewed adolescents in Northern Ireland to investigate their experiences with the divorce process and help provided by family, friends, and professionals. They considered the separation/divorce process long, frequently underpinned by acrimony and violence. Extended family and peers provided great support. Many teens used specialist counselors…

  14. Northern blotting analysis

    DEFF Research Database (Denmark)

    Josefsen, Knud; Nielsen, Henrik

    2011-01-01

    Northern blotting analysis is a classical method for analysis of the size and steady-state level of a specific RNA in a complex sample. In short, the RNA is size-fractionated by gel electrophoresis and transferred by blotting onto a membrane to which the RNA is covalently bound. Then, the membrane...... is analysed by hybridization to one or more specific probes that are labelled for subsequent detection. Northern blotting is relatively simple to perform, inexpensive, and not plagued by artefacts. Recent developments of hybridization membranes and buffers have resulted in increased sensitivity closing...

  15. Southern Great Plains Safety Orientation

    Energy Technology Data Exchange (ETDEWEB)

    Schatz, John

    2014-05-01

    Welcome to the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ARM) Southern Great Plains (SGP) site. This U.S. Department of Energy (DOE) site is managed by Argonne National Laboratory (ANL). It is very important that all visitors comply with all DOE and ANL safety requirements, as well as those of the Occupational Safety and Health Administration (OSHA), the National Fire Protection Association, and the U.S. Environmental Protection Agency, and with other requirements as applicable.

  16. Early warning signals of desertification transitions in semiarid ecosystems.

    Science.gov (United States)

    Corrado, Raffaele; Cherubini, Anna Maria; Pennetta, Cecilia

    2014-12-01

    The identification of early warning signals for regime shifts in ecosystems is of crucial importance given their impact in terms of economic and social effects. We present here the results of a theoretical study on the desertification transition in semiarid ecosystems under external stress. We performed numerical simulations based on a stochastic cellular automaton model, and we studied the dynamics of the vegetation clusters in terms of percolation theory, assumed as an effective tool for analyzing the geometrical properties of the clusters. Focusing on the role played by the strength of external stresses, measured by the mortality rate m, we followed the progressive degradation of the ecosystem for increasing m, identifying different stages: first, the fragmentation transition occurring at relatively low values of m, then the desertification transition at higher mortality rates, and finally the full desertification transition corresponding to the extinction of the vegetation and the almost complete degradation of the soil, attained at the maximum value of m. For each transition we calculated the spanning probabilities as functions of m and the percolation thresholds according to different spanning criteria. The identification of the different thresholds is proposed as an useful tool for monitoring the increasing degradation of real-world finite-size systems. Moreover, we studied the time fluctuations of the sizes of the biggest clusters of vegetated and nonvegetated cells over the entire range of mortality values. The change of sign in the skewness of the size distributions, occurring at the fragmentation threshold for the biggest vegetation cluster and at the desertification threshold for the nonvegetated cluster, offers new early warning signals for desertification. Other new and robust indicators are given by the maxima of the root-mean-square deviation of the distributions, which are attained respectively inside the fragmentation interval, for the vegetated

  17. Water use efficiency and functional traits of a semiarid shrubland

    Science.gov (United States)

    Perez-Priego, Oscar; Lopez-Ballesteros, Ana; Sánchez-Cañete, Enrique P.; Serrano-Ortiz, Penélope; Carrara, Arnaud; Palomares-Palacio, Agustí; Oyonarte, Cecilio; Domingo, Francisco; Kowalski, Andrew S.

    2013-04-01

    In semiarid climates, water is the fundamental factor determining ecosystem productivity and thereby the capacity for carbon sequestration. Increased water use efficiency (WUE), the ratio of carbon dioxide assimilation (canopy photosynthesis, Pc) to water transpired (canopy evaporation, Ec), is assumed to be an adaptive strategy for sclerophyll shrublands to improve productivity and stress resistance in water-limited environments. However, the real complexity of WUE lies in its dependence on both plant physiological traits (e.g. stomatal resistance, photosynthetic capacity, leaf chemical composition, structure) and on environmental conditions (e.g. atmospheric CO2 concentration, vapour pressure deficit, temperature, light, soil water availability). We used a transient-state closed canopy-chamber to characterise CO2 and water vapour exchanges at the whole plant scale under different environmental conditions and phenological stages. Diurnal and seasonal variations in Pc, Ec and WUE were explained by both physiological and environmental variables. All species showed symmetric patterns in both Pc and Ec when not water limited, but asymmetry during summer drought when leaf water potential was low. During drought, grasses (Festuca sp.) showed a marked decline in functioning (Pc and Ec), whereas shrubs (Genista sp., Hormathophylla sp.) maintained spring-like assimilation rates all morning until stomatal controls shut down gas exchanges. While grasses showed the highest WUE when not water limited, their near senescence during summer drought yielded the lowest WUE. Shrubs showed reduced WUE under moderate drought stress, in contradiction to the assumptions made in global ecosystem models. The importance of the appropriate time-scale for calculating WUE (daily versus hourly), together with water use strategies and ecological functions of individual species, will be further discussed.

  18. Ecohydrology and tipping points in semiarid australian rangelands

    Science.gov (United States)

    Saco, P. M.; Azadi, S.; Moreno de las Heras, M.; Willgoose, G. R.

    2017-12-01

    Semiarid landscapes are often characterised by a spatially heterogeneous vegetation cover forming mosaics of patches with dense vegetation within bare soil. This patchy vegetation cover, which is linked to the healthy function of these ecosystems, is sensitive to human disturbances that can lead to degradation. Previous work suggests that vegetation loss below a critical value can lead to a sudden decrease in landscape functionality following threshold behaviour. The decrease in vegetation cover is linked to erosion and substantial water losses by increasing landscape hydrological connectivity. We study these interactions and the possible existence of tipping points in the Mulga land bioregion, by combining remote sensing observations and results from an eco-geomorphologic model to investigate changes in ecosystem connectivity and the existence of threshold behaviour. More than 30 sites were selected along a precipitation gradient spanning a range from approximately 250 to 500 mm annual rainfall. The analysis of vegetation patterns is derived from high resolution remote sensing images (IKONOS, QuickBird, Pleiades) and MODIS NDVI, which combined with local precipitation data is used to compute rainfall use efficiency to assess the ecosystem function. A critical tipping point associated to loss of vegetation cover appears in the sites with lower annual precipitation. We found that this tipping point behaviour decreases for sites with higher rainfall. We use the model to investigate the relation between structural and functional connectivity and the emergence of threshold behaviour for selected plots along this precipitation gradient. Both observations and modelling results suggest that sites with higher rainfall are more resilient to changes in surface connectivity. The implications for ecosystem resilience and land management are discussed

  19. Climate-smart crop production in semi-arid areas through increased knowledge of varieties, environment and management factors

    NARCIS (Netherlands)

    Murungweni, C.; Wijk, van M.T.; Smaling, E.M.A.; Giller, K.E.

    2016-01-01

    In large regions of sub-Saharan Africa, semi-arid conditions are likely to increase with climate change, yet these regions are becoming more important to feed production zones due to increasing population pressure. A production system in the semi-arid south eastern Zimbabwe was studied to assess

  20. Analysis and evaluation of tillage on an alfisol in a semi-arid tropical region of India

    NARCIS (Netherlands)

    Klaij, M.C.

    1983-01-01

    Tillage field experiments were conducted on Alfisols in a semi-arid tropical environment in India. The research was conducted within the framework of the Farming Systems Research Program of the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT).

    To put the

  1. Arid and semiarid land stewardship: A 10-year review of accomplishments and contributions of the lnternational Arid Lands Consortium

    Science.gov (United States)

    Peter F. Ffolliott; Jeffrey O. Dawson; James T. Fisher; Itshack Moshe; Darrell W. DeBoers; Timothy. E. Fulbright; John Tracy; Abdullah Al Musa; Carter Johnson; Jim P. M. Chamie

    2001-01-01

    The International Arid Lands Consortium (IALC) was established in 1990 to promote research, education, and training activities related to the development, management, and restoration or reclamation of arid and semiarid lands worldwide. The IALC, a leading international organization, supports ecological sustainability and development of arid and semiarid lands. Building...

  2. Large-scale hydrological modelling in the semi-arid north-east of Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Guentner, A

    2002-09-01

    Semi-arid areas are characterized by small water resources. An increasing water demand due to population growth and economic development as well as a possible decreasing water availability in the course of climate change may aggravate water scarcity in future in these areas. The quantitative assessment of the water resources is a prerequisite for the development of sustainable measures of water management. For this task, hydrological models within a dynamic integrated framework are indispensable tools. The main objective of this study is to develop a hydrological model for the quantification of water availability over a large geographic domain of semi-arid environments. The study area is the Federal State of Ceara in the semi-arid north-east of Brazil. Surface water from reservoirs provides the largest part of water supply. The area has recurrently been affected by droughts which caused serious economic losses and social impacts like migration from the rural regions. (orig.)

  3. Are acid volatile sulfides (AVS) important trace metals sinks in semi-arid mangroves?

    Science.gov (United States)

    Queiroz, Hermano Melo; Nóbrega, Gabriel Nuto; Otero, Xose L; Ferreira, Tiago Osório

    2018-01-01

    Acid-volatile sulfides (AVS) formation and its role on trace metals bioavailability were studied in semi-arid mangroves. The semi-arid climatic conditions at the studied sites, marked by low rainfall and high evapotranspiration rates, clearly limited the AVS formation (AVS contents varied from 0.10 to 2.34μmolg -1 ) by favoring oxic conditions (Eh>+350mV). The AVS contents were strongly correlated with reactive iron and organic carbon (r=0.84; r=0.83 respectively), evidencing their dominant role for AVS formation under semi-arid conditions. On the other hand, the recorded ΣSEM/AVS values remained >1 evidencing a little control of AVS over the bioavailability of trace metals and, thus, its minor role as a sink for toxic metals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Estimation of groundwater recharge via deuterium labelling in the semi-arid Cuvelai-Etosha Basin, Namibia.

    Science.gov (United States)

    Beyer, Matthias; Gaj, Marcel; Hamutoko, Josefina Tulimeveva; Koeniger, Paul; Wanke, Heike; Himmelsbach, Thomas

    2015-01-01

    The stable water isotope deuterium ((2)H) was applied as an artificial tracer ((2)H2O) in order to estimate groundwater recharge through the unsaturated zone and describe soil water movement in a semi-arid region of northern central Namibia. A particular focus of this study was to assess the spatiotemporal persistence of the tracer when applied in the field on a small scale under extreme climatic conditions and to propose a method to obtain estimates of recharge in data-scarce regions. At two natural sites that differ in vegetation cover, soil and geology, 500 ml of a 70% (2)H2O solution was irrigated onto water saturated plots. The displacement of the (2)H peak was analyzed 1 and 10 days after an artificial rain event of 20 mm as well as after the rainy season. Results show that it is possible to apply the peak displacement method for the estimation of groundwater recharge rates in semi-arid environments via deuterium labelling. Potential recharge for the rainy season 2013/2014 was calculated as 45 mm a(-1) at 5.6 m depth and 40 mm a(-1) at 0.9 m depth at the two studied sites, respectively. Under saturated conditions, the artificial rain events moved 2.1 and 0.5 m downwards, respectively. The tracer at the deep sand site (site 1) was found after the rainy season at 5.6 m depth, corresponding to a displacement of 3.2 m. This equals in an average travel velocity of 2.8 cm d(-1) during the rainy season at the first site. At the second location, the tracer peak was discovered at 0.9 m depth; displacement was found to be only 0.4 m equalling an average movement of 0.2 cm d(-1) through the unsaturated zone due to an underlying calcrete formation. Tracer recovery after one rainy season was found to be as low as 3.6% at site 1 and 1.9% at site 2. With an in situ measuring technique, a three-dimensional distribution of (2)H after the rainy season could be measured and visualized. This study comprises the first application of the peak displacement method using a

  5. Northern blotting analysis

    DEFF Research Database (Denmark)

    Josefsen, Knud; Nielsen, Henrik

    2011-01-01

    is analysed by hybridization to one or more specific probes that are labelled for subsequent detection. Northern blotting is relatively simple to perform, inexpensive, and not plagued by artefacts. Recent developments of hybridization membranes and buffers have resulted in increased sensitivity closing...

  6. insurgencies in northern Uganda

    African Journals Online (AJOL)

    International Criminal Court (ICC) investigations into the LRA activities. ... and the rebel movements in northern Uganda, see Human Rights Watch 2003, and ... the ICC, Luis Moreno Ocampo, met at Hotel Intercontinental, Hyde Park, London, ..... expunge criminal liability for war crimes and crimes against humanity, appear.

  7. Comparative habitat use of sympatric Mexican spotted and great horned owls

    Science.gov (United States)

    Joseph L. Ganey; William M. Block; Jeffrey S. Jenness; Randolph A. Wilson

    1997-01-01

    To provide information on comparative habitat use, we studied radiotagged Mexican spotted owls (Strix occidentalis lucida: n = 13) and great horned owls (Bubo virginianus: n = 4) in northern Arizona. Home-range size (95% adaptive kernel estimate) did not differ significantly between species during either the breeding or nonbreeding...

  8. Quantitative analysis and implications of drainage morphometry of the Agula watershed in the semi-arid northern Ethiopia

    Science.gov (United States)

    Fenta, Ayele Almaw; Yasuda, Hiroshi; Shimizu, Katsuyuki; Haregeweyn, Nigussie; Woldearegay, Kifle

    2017-11-01

    This study aimed at quantitative analysis of morphometric parameters of Agula watershed and its sub-watersheds using remote sensing data, geographic information system, and statistical methods. Morphometric parameters were evaluated from four perspectives: drainage network, watershed geometry, drainage texture, and relief characteristics. A sixth-order river drains Agula watershed and the drainage network is mainly dendritic type. The mean bifurcation ratio ( R b) was 4.46 and at sub-watershed scale, high R b values ( R b > 5) were observed which might be expected in regions of steeply sloping terrain. The longest flow path of Agula watershed is 48.5 km, with knickpoints along the main river which could be attributed to change of lithology and major faults which are common along the rift escarpments. The watershed has elongated shape suggesting low peak flows for longer duration and hence easier flood management. The drainage texture analysis revealed fine drainage which implies the dominance of impermeable soft rock with low resistance against erosion. High relief and steep slopes dominates, by which rough landforms (hills, breaks, and low mountains) make up 76% of the watershed. The S-shaped hypsometric curve with hypsometric integral of 0.4 suggests that Agula watershed is in equilibrium or mature stage of geomorphic evolution. At sub-watershed scale, the derived morphometric parameters were grouped into three clusters (low, moderate, and high) and considerable spatial variability was observed. The results of this study provide information on drainage morphometry that can help better understand the watershed characteristics and serve as a basis for improved planning, management, and decision making to ensure sustainable use of watershed resources.

  9. Land-atmosphere interaction and disaster-causing process of drought in northern China: observation and experiment (DroughtPEX_China)

    Science.gov (United States)

    Li, Yaohui

    2017-04-01

    aims to establish a complete observation &experiment system for droughts particularly over the arid and semi-arid regions in northern China. Relying on the existing meteorological observation network and experimental bases, the DroughtPEX_China implemented interdisciplinary, comprehensive and systemic drought-scientific experiment including the routine observation, intensive and special observation, and the artificially field control test for the drought forming and reducing. Such large observation &experiment will promote a large step or theoretical breakthrough on the knowledge of the complex dynamic process for the formation and development of drought disasters, the mechanism of the water-energy cycle in the atmosphere-soil-vegetation on multi-scales, and the interrelationship in the atmosphere, agriculture and hydrological droughts. The ultimate purpose of DroughtPEX_China is to make great progress on the technology of accurate drought monitoring, risk assessment and early warning. This paper will introduce the Drought PEX_China with the scientific goal, experiment design and layout, preliminary results, information sharing, and its promoting role on international cooperation of drought scientific research. Key words: Disaster-causing process of drought; Observation & experiment; Northern China

  10. First record of Chantransia macrospora Wood, 1887 (Batrachospermales, Rhodophyta in semi-arid northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Janiele França Vasconcelos

    2014-12-01

    Full Text Available This study presents the first record of Chantransia macrospora in the state of Rio Grande do Norte, in the semi-arid region of northeastern Brazil. Analyses of periphytic algae revealed C. macrospora individuals associated in particular with shells of Melanoides tuberculatus, a non-native species, suggesting that C. macrospora have been introduced into systems associated with the gastropods. In this context, new records of C. macrospora are still expected for the Brazilian semi-arid region in the next years.

  11. First record of Chantransia macrospora Wood, 1887 (Batrachospermales, Rhodophyta in semi-arid northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Janiele França Vasconcelos

    2014-08-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2014v27n4p129 This study presents the first record of Chantransia macrospora in the state of Rio Grande do Norte, in the semi-arid region of northeastern Brazil. Analyses of periphytic algae revealed C. macrospora individuals associated in particular with shells of Melanoides tuberculatus, a non-native species, suggesting that C. macrospora have been introduced into systems associated with the gastropods. In this context, new records of C. macrospora are still expected for the Brazilian semi-arid region in the next years.

  12. Learning and the Great Moderation

    OpenAIRE

    Bullard, James B.; Singh, Aarti

    2009-01-01

    We study a stylized theory of the volatility reduction in the U.S. after 1984 - the Great Moderation - which attributes part of the stabilization to less volatile shocks and another part to more difficult inference on the part of Bayesian households attempting to learn the latent state of the economy. We use a standard equilibrium business cycle model with technology following an unobserved regime-switching process. After 1984, according to Kim and Nelson (1999a), the variance of U.S. macroec...

  13. Pricing regulations in Great Britain

    International Nuclear Information System (INIS)

    Cicoletti, G.

    1993-01-01

    This paper briefly describes the structure and functions of Great Britain's essential electric power regulatory authority institutionalized by the 1989 British Electricity Act, i.e., the Office of Electricity Regulation, OFFER, and the responsibilities and tasks of the head of OFFER -the Director General of Electricity Supply (DGES). In particular, with regard to the latter, the paper describes how the DGES works together with regional electricity commissions to ensure the respect, by the various utilities, of consumer price caps and compliance with overall quality of service standards, as well as, to oversee 'pooling' activities by producers and distributors

  14. Pricing regulations in Great Britain

    International Nuclear Information System (INIS)

    Cicoletti, G.

    1993-01-01

    This paper briefly describes the structure and functions of Great Britain's essential electric power regulatory authority institutionalized by the 1989 British Electricity Act, i.e., the Office of Electricity Regulation, OFFER, and the responsibilities and tasks of the head of OFFER - the Director General of Electricity Supply (DGES). In particular, with regard to the latter, the paper describes how the DGES works together with regional electricity commissions to ensure the respect, by the various utilities, of consumer price caps and compliance with overall quality of service standards, as well as, to oversee 'pooling' activities by producers and distributors

  15. What killed Alexander the Great?

    Science.gov (United States)

    Battersby, Cameron

    2007-01-01

    The cause of the death of the Macedonian King, Alexander the Great, at Babylon in 323 BC has excited interest and conjecture throughout the ages. The information available in the surviving ancient sources, none of which is contemporaneous, has been reviewed and compared with modern knowledge as set out in several well-known recent surgical texts. The ancient sources record epic drinking by the Macedonian nobility since at least the time of Phillip II, Alexander's father. Alexander's sudden illness and death is likely to have resulted from a surgical complication of acute alcoholic excess.

  16. Commanders of the Great Victory

    Directory of Open Access Journals (Sweden)

    Anatoly Dmitriyevich Borshchov

    2015-01-01

    Full Text Available The honorary title of «commander» as well as the «admiral» is granted to a military or naval figure on the basis of public recognition of his personal contribution to the success of actions. Generals are usually individuals with creative thinking, the ability to foresee the development of military events. Generals usually have such personality traits as a strong will and determination, rich combat experience, credibility and high organizational skills. In an article dedicated to the 70th anniversary of the Soviet victory in the Great War examines the experience of formation and practice of the most talent-ed Soviet military leaders.

  17. The Great Whale review and the federal government's disappearing act

    International Nuclear Information System (INIS)

    Fenge, T.

    1991-01-01

    After considerable political and legal pressure, the Canadian and Quebec governments, plus the electric utility Hydro-Quebec, agreed to a global review and environmental assessment of the Great Whale hydroelectric project in northern Quebec. The assessment is being handled by five committees, each covering distinct areas of geography and responsibility. The initial task of the review committees was to determine the scope of the assessment, and 23 days of public hearings were held in northern and southern Quebec and on the Belcher Islands. The federal government's absence from the scoping hearings was a curious development, since federal agencies normally participate actively in such hearings. A federal guidelines order upheld recently by the Canadian Supreme Court requires federal participation in environmental assessment processes. The Great Whale project affects areas of federal jurisdiction as well as areas outside Quebec, and federal expertise in such matters as the marine environment is crucial in airing environmental issues related to the project. Interviews with federal officials on the reasons for federal absence are summarized. It is concluded that the federal agencies did not really regard scoping hearings as part of the public review, and that this review does not start until hearings begin on the environmental impact statement

  18. Great apes prefer cooked food.

    Science.gov (United States)

    Wobber, Victoria; Hare, Brian; Wrangham, Richard

    2008-08-01

    The cooking hypothesis proposes that a diet of cooked food was responsible for diverse morphological and behavioral changes in human evolution. However, it does not predict whether a preference for cooked food evolved before or after the control of fire. This question is important because the greater the preference shown by a raw-food-eating hominid for the properties present in cooked food, the more easily cooking should have been adopted following the control of fire. Here we use great apes to model food preferences by Paleolithic hominids. We conducted preference tests with various plant and animal foods to determine whether great apes prefer food items raw or cooked. We found that several populations of captive apes tended to prefer their food cooked, though with important exceptions. These results suggest that Paleolithic hominids would likewise have spontaneously preferred cooked food to raw, exapting a pre-existing preference for high-quality, easily chewed foods onto these cooked items. The results, therefore, challenge the hypothesis that the control of fire preceded cooking by a significant period.

  19. Studying The Great Russian Revolution

    Directory of Open Access Journals (Sweden)

    A. V. Torkunov

    2017-01-01

    Full Text Available The article revises an established view of Russian Revolution as two separate events - February Revolution and October Revolution. The author supports the concept of the «Great Russian Revolution», which unites these two events in a single process of revolutionary development. The author draws attention to the following advantages of the concept under consideration. First, it conceptualizes the revolution as a process contingent of a local and global historical context. In this sense, the revolution is presented as the transition of society to the modern stage of development, meaning the transition to modernity. Second, revolutionary events in Russia are considered from the point of view of the evolution of the spatial and socioeconomic distribution and rearrangement of key social groups: peasantry, elites, national and ethnic minorities. Third, it takes into account the personal factor in the revolutionary events, the influence of individual personalities on escalation or the reduction of socio-political tensions. Fourth, it draws attention to the fact that revolutions imply the use of various forms of political violence. Each revolution is characterized by a unique correlation of forms and intensity of political violence. Finally, it gives a normative assessment of the Revolution, encouraging a national discussion on the results and consequences of this great event.

  20. Second-Generation Outcomes of the Great Migration.

    Science.gov (United States)

    Alexander, J Trent; Leibbrand, Christine; Massey, Catherine; Tolnay, Stewart

    2017-12-01

    The mass migration of African Americans out of the South during the first two-thirds of the twentieth century represents one of the most significant internal migration flows in U.S. Those undertaking the Great Migration left the South in search of a better life, and their move transformed the cultural, social, and political dynamics of African American life specifically and U.S. society more generally. Recent research offers conflicting evidence regarding the migrants' success in translating their geographic mobility into economic mobility. Due in part to the lack of a large body of longitudinal data, almost all studies of the Great Migration have focused on the migrants themselves, usually over short periods of their working lives. Using longitudinally linked census data, we take a broader view, investigating the long-term economic and social effects of the Great Migration on the migrants' children. Our results reveal modest but statistically significant advantages in education, income, and poverty status for the African American children of the Great Migration relative to the children of southerners who remained in the South. In contrast, second-generation white migrants experienced few benefits from migrating relative to southern or northern stayers.

  1. Systematic revision of the marbled velvet geckos (Oedura marmorata species complex, Diplodactylidae) from the Australian arid and semi-arid zones.

    Science.gov (United States)

    Oliver, Paul M; Doughty, Paul

    2016-03-08

    Lizards restricted to rocky habitats often comprise numerous deeply divergent lineages, reflecting the disjunct nature of their preferred habitat and the capacity of rocky habitats to function as evolutionary refugia. Here we review the systematics and diversity of the predominantly saxicoline Australian marbled velvet geckos (genus Oedura) in the Australian arid and semi-arid zones using newly-gathered morphological data and previously published genetic data. Earlier work showed that four largely allopatric and genetically divergent lineages are present: Western (Pilbara and Gascoyne regions), Gulf (west and south of the Gulf of Carpentaria), Central (central ranges) and Eastern (Cooper and Darling Basins). None of these four populations are conspecific with true O. marmorata, a seperate species complex that is restricted to the Top End region of the Northern Territory. Top End forms share a short, bulbous tail whereas the other four lineages treated here possess a long, tapering tail. Morphological differences among the arid and semi-arid lineages include smaller body size, tapering lamellae and a shorter tail for the Gulf population, and a partially divided rostral scale in the Western population compared to the Central and Eastern populations. Accordingly, we resurrect O. cincta de Vis from synonymy for the Central and Eastern lineages, and regard this species as being comprised of two evolutionary significant units. We also describe the Gulf and Western lineages as new species: Oedura bella sp. nov. and O. fimbria sp. nov., respectively. We note that a predominantly arboreal lineage (the Eastern lineage of O. cincta) is more widely distributed than the other lineages and is phylogenetically nested within a saxicoline clade, but tends to have a deeper head and shorter limbs, consistent with morphological variation observed in other lizard radiations including both saxicoline and arboreal taxa.

  2. Trends and variations of pH and hardness in a typical semi-arid river in a monsoon climate region during 1985-2009.

    Science.gov (United States)

    Hao, Shaonan; Li, Xuyong; Jiang, Yan; Zhao, Hongtao; Yang, Lei

    2016-09-01

    The rapid growth of urbanization and industrialization, along with dramatic climate change, has strongly influenced hydrochemical characteristics in recent decades in China and thus could cause the variation of pH and general total hardness of a river. To explore such variations and their potential influencing factors in a river of the monsoon climate region, we analyzed a long-term monitoring dataset of pH, SO4 (2-), NOx, general total hardness (GH), Mg(2+), Ca(2+), and Cl(-) in surface water and groundwater in the Luan River basin from 1985 to 2009. The nonparametric Seasonal Kendall trend test was used to test the long-term trends of pH and GH. Relationship between the affecting factors, pH and GH were discussed. Results showed that pH showed a decreasing trend and that GH had an increasing trend in the long-term. Seasonal variation of pH and GH was mainly due to the typical monsoon climate. Results of correlation analysis showed that the unit area usage amounts of chemical fertilizer, NO3 (-), and SO4 (2-) were negatively correlated with pH in groundwater. In addition, mining activity affected GH spatial variation. Acid deposition, drought, and increasing the use of chemical fertilizers would contribute to the acidification trend, and mining activities would affect the spatial variation of GH. Variations of precipitation and runoff in semi-arid monsoon climate areas had significant influences on the pH and GH. Our findings implied that human activities played a critical role in river acidification in the semi-arid monsoon climate region of northern China.

  3. Commercialization of animal-derived remedies as complementary medicine in the semi-arid region of Northeastern Brazil.

    Science.gov (United States)

    Alves, Rômulo R N; Léo Neto, Nivaldo A; Brooks, Sharon E; Albuquerque, Ulysses P

    2009-07-30

    In this study, we aim to document the use of animal species in traditional medicine and healing practices in the semi-arid region of Northeastern Brazil. While widespread and of great importance to large population that has limited access to contemporary medicine, such practices are poorly understood and the potential value of medicinal animal species largely unknown. Based on interviews with the merchants of medicinal animals, we calculated the informant consensus factor (ICF) to determine the consensus over which species are effective for particular ailments, as well as the species relative importance to determine the extent of potential utilization of each species. We describe the therapeutic effects of 36 animal species used medicinally. The zootherapeutical products sold commercially are used to treat 40 health problems that were classified into 10 broad categories. We also highlight those species valued for their effectiveness against a range of ailments. The highest ICF value (0.91) was cited for diseases of the skin and subcutaneous tissue, which include relief of symptoms such as acne and furuncles. This study demonstrates that many animal species play an important role in healing practices. Animals provide the raw materials for remedies prescribed clinically and are also used in the form of amulets and charms in magic-religious rituals and ceremonies. The medicinal value of animal species depends on the local knowledge that exists within user communities, and therefore, the conservation of animal species is imperative to the preservation of local medicinal knowledge and culture.

  4. Lake Area Changes and Their Influence on Factors in Arid and Semi-Arid Regions along the Silk Road

    Directory of Open Access Journals (Sweden)

    Chao Tan

    2018-04-01

    Full Text Available In the context of global warming, the changes in major lakes and their responses to the influence factors in arid and semi-arid regions along the Silk Road are especially important for the sustainable development of local water resources. In this study, the areas of 24 lakes were extracted using MODIS NDVI data, and their spatial-temporal characteristics were analyzed. In addition, the relationship between lake areas and the influence factors, including air temperature, precipitation, evapotranspiration, land use and land cover change (LULCC and population density in the watersheds, were investigated. The results indicated that the areas of most lakes shrank, and the total area decreased by 22,189.7 km2 from 2001 to 2016, except for those of the lakes located on the Qinghai-Tibetan Plateau. The air temperature was the most important factor for all the lakes and increased at a rate of 0.113 °C/a during the past 16 years. LULCC and the increasing population density markedly influenced the lakes located in the middle to western parts of this study area. Therefore, our results connecting lake area changes in the study region highlight the great challenge of water resources and the urgency of implementation of the green policy in the One Belt and One Road Initiative through international collaboration.

  5. Occurrence and identification of the etiologic agents of plant diseases in cactus (Opuntia ficus-indica Mill. in the semi-arid region of Paraiba

    Directory of Open Access Journals (Sweden)

    Anne Evelyne Franco de Souza

    2010-01-01

    Full Text Available Cactus forage (Opuntia ficus-indica Mill., intensely cultivated in dry regions of northeast Brazil, although well adapted to the harsh semi-arid climate is affected by major problems such as pests and diseases, responsible for significant losses in production. This study aimed to investigate the occurrence and diversity of the etiologic agents of diseases of cactus cultivated in 38 municipalities in the semi-arid region of Paraiba. The analyses were conducted and processed at the Laboratory of Phytopathology of the Centro de Ciências Agrárias da Universidade Federal da Paraíba, in Areia - PB. Starting from sick cladodes isolations, multiplications and identifications of the found microorganisms were made. The identification of the microorganisms was achieved through observations of the macro and micromorphological characteristics of the cultures and tests of Gram and pathogenicity. Great incidence and diversity of microorganisms was verified in the cacti researched, but the highest occurrence was mainly that of fungus. The fungi of widest occurrence were: Scytallidium lignicola, Alternate tenuis, Macrophomina phaseolina, Cladosporium cladosporides, Lasiodiplodia theobromae, Fusarium oxysporum f. sp. opuntiarum, Curvularia lunata, Aspergillus niger, Nigrospora sphaerica, Colletotrichum gloeosporioides, Exserohilum turcicum, Pestalotia pitospora, Rhizopus stolonifer, Rhizoctonia solani and Sphaceloma protearum. A bacterium was also detected that was suspected to belong to the Erwinia sp. strain. Satisfaction of the Postulates of Koch proved the infectious nature of the detected microorganisms. High occurrence of the fungus S. lignicola, an agent of scale rot disease in 100% of the places researched, was observed. This fact is of great concern, since the progression of the disease can cause significant losses in production.

  6. The Great Hedge of India

    International Nuclear Information System (INIS)

    Moxham, Roy

    2015-01-01

    The 'Great Hedge of India', a 3 700 kilometre-long hedge installed by the British customs to safeguard the colonial salt tax system and avoid salt smuggling totally faded from both memory and records (e.g. maps) in less than a century. Roy Moxham found traces of the hedge in a book footnote and searched it for several years until he found its meagre remains. The speaker wrote a book about this quest. He said that this story reveals how things disappear when they are no longer useful and, especially, when they are linked to parts of history that are not deemed particularly positive (the hedge was a means of colonial power)

  7. Gypsum karst in Great Britain

    Directory of Open Access Journals (Sweden)

    Cooper A.H.

    1996-01-01

    Full Text Available In Great Britain the most spectacular gypsum karst development is in the Zechstein gypsum (late Permian mainly in north-eastern England. The Midlands of England also has some karst developed in the Triassic gypsum in the vicinity of Nottingham. Along the north-east coast, south of Sunderland, well-developed palaeokarst, with magnificent breccia pipes, was produced by dissolution of Permian gypsum. In north-west England a small gypsum cave system of phreatic origin has been surveyed and recorded. A large actively evolving phreatic gypsum cave system has been postulated beneath the Ripon area on the basis of studies of subsidence and boreholes. The rate of gypsum dissolution here, and the associated collapse lead to difficult civil engineering and construction conditions, which can also be aggravated by water abstraction.

  8. Great-Britain at CERN

    CERN Multimedia

    C. Laignel

    2004-01-01

    From 23 to 25 November 2004 Administration Building Bldg 60/61 - ground and 1st floor 09.30 - 17.30 Twenty five companies will present their latest technology at the "Great-Britain at CERN" exhibition. British industry will exhibit products and technologies which are related to the field of particle physics. The main subjects are: electrical engineering, electronics, mechanical engineering, vacuum & low temperatures technologies, particles detectors and telecommunications. The exhibition is organised by BEAMA Exhibitions, The British Electrotechnical and Allied Manufacturer's Association There follows : the list of exhibitors. A detailed programme will be available in due course at : your Departemental secretariat, the reception information desk, Building 33, the exhibition. A detailed list of firms is available under the following FI link: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm 1 Accles & Pollock 2 A S Scientific Products Ltd 3 C...

  9. Great Basin Experimental Range: Annotated bibliography

    Science.gov (United States)

    E. Durant McArthur; Bryce A. Richardson; Stanley G. Kitchen

    2013-01-01

    This annotated bibliography documents the research that has been conducted on the Great Basin Experimental Range (GBER, also known as the Utah Experiment Station, Great Basin Station, the Great Basin Branch Experiment Station, Great Basin Experimental Center, and other similar name variants) over the 102 years of its existence. Entries were drawn from the original...

  10. The origin of 'Great Walls'

    International Nuclear Information System (INIS)

    Shandarin, Sergei F.

    2009-01-01

    A new semi-analytical model that explains the formation and sizes of the 'great walls' - the largest structures observed in the universe is suggested. Although the basis of the model is the Zel'dovich approximation it has been used in a new way very different from the previous studies. Instead of traditional approach that evaluates the nonlinear density field it has been utilized for identification of the regions in Lagrangian space that after the mapping to real or redshift space (depending on the kind of structure is studied) end up in the regions where shell-crossing occurs. The set of these regions in Lagrangian space form the progenitor of the structure and after the mapping it determines the pattern of the structure in real or redshift space. The particle trajectories have crossed in such regions and the mapping is no longer unique there. The progenitor after mapping makes only one stream in the multi-stream flow regions therefore it does not comprise all the mass. Nevertheless, it approximately retains the shape of the structure. The progenitor of the structure in real space is determined by the linear density field along with two non-Gaussian fields derived from the initial potential. Its shape in Eulerian space is also affected by the displacement field. The progenitor of the structure in redshift space also depends on these fields but in addition it is strongly affected by two anisotropic fields that determine the pattern of great walls as well as their huge sizes. All the fields used in the mappings are derived from the linear potential smoothed at the current scale of nonlinearity which is R nl = 2.7 h −1 Mpc for the adopted parameters of the ΛCDM universe normalized to σ 8 = 0.8. The model predicts the existence of walls with sizes significantly greater than 500 h −1 Mpc that may be found in sufficiently large redshift surveys

  11. The Great Warming Brian Fagan

    Science.gov (United States)

    Fagan, B. M.

    2010-12-01

    The Great Warming is a journey back to the world of a thousand years ago, to the Medieval Warm Period. Five centuries of irregular warming from 800 to 1250 had beneficial effects in Europe and the North Atlantic, but brought prolonged droughts to much of the Americas and lands affected by the South Asian monsoon. The book describes these impacts of warming on medieval European societies, as well as the Norse and the Inuit of the far north, then analyzes the impact of harsh, lengthy droughts on hunting societies in western North America and the Ancestral Pueblo farmers of Chaco Canyon, New Mexico. These peoples reacted to drought by relocating entire communities. The Maya civilization was much more vulnerable that small-scale hunter-gatherer societies and subsistence farmers in North America. Maya rulers created huge water storage facilities, but their civilization partially collapsed under the stress of repeated multiyear droughts, while the Chimu lords of coastal Peru adapted with sophisticated irrigation works. The climatic villain was prolonged, cool La Niñalike conditions in the Pacific, which caused droughts from Venezuela to East Asia, and as far west as East Africa. The Great Warming argues that the warm centuries brought savage drought to much of humanity, from China to Peru. It also argues that drought is one of the most dangerous elements in today’s humanly created global warming, often ignored by preoccupied commentators, but with the potential to cause over a billion people to starve. Finally, I use the book to discuss the issues and problems of communicating multidisciplinary science to the general public.

  12. Plastic debris in great skua (Stercorarius skua) pellets corresponds to seabird prey species.

    Science.gov (United States)

    Hammer, S; Nager, R G; Johnson, P C D; Furness, R W; Provencher, J F

    2016-02-15

    Plastic is a common item in marine environments. Studies assessing seabird ingestion of plastics have focused on species that ingest plastics mistaken for prey items. Few studies have examined a scavenger and predatory species that are likely to ingest plastics indirectly through their prey items, such as the great skua (Stercorarius skua). We examined 1034 regurgitated pellets from a great skua colony in the Faroe Islands for plastics and found approximately 6% contained plastics. Pellets containing remains of Northern fulmars (Fulmarus glacialis) had the highest prevalence of plastic. Our findings support previous work showing that Northern fulmars have higher loads of plastics than other sympatric species. This study demonstrates that marine plastic debris is transferred from surface feeding seabird species to predatory great skuas. Examination of plastic ingestion in species that do not ingest plastics directly can provide insights into how plastic particles transfer vertically within the food web. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Northern pipelines : backgrounder

    International Nuclear Information System (INIS)

    2002-04-01

    Most analysts agree that demand for natural gas in North America will continue to grow. Favourable market conditions created by rising demand and declining production have sparked renewed interest in northern natural gas development. The 2002 Annual Energy Outlook forecasted U.S. consumption to increase at an annual average rate of 2 per cent from 22.8 trillion cubic feet to 33.8 TCF by 2020, mostly due to rapid growth in demand for electric power generation. Natural gas prices are also expected to increase at an annual average rate of 1.6 per cent, reaching $3.26 per thousand cubic feet in 2020. There are currently 3 proposals for pipelines to move northern gas to US markets. They include a stand-alone Mackenzie Delta Project, the Alaska Highway Pipeline Project, and an offshore route that would combine Alaskan and Canadian gas in a pipeline across the floor of the Beaufort Sea. Current market conditions and demand suggest that the projects are not mutually exclusive, but complimentary. The factors that differentiate northern pipeline proposals are reserves, preparedness for market, costs, engineering, and environmental differences. Canada has affirmed its role to provide the regulatory and fiscal certainty needed by industry to make investment decisions. The Government of the Yukon does not believe that the Alaska Highway Project will shut in Mackenzie Delta gas, but will instead pave the way for development of a new northern natural gas industry. The Alaska Highway Pipeline Project will bring significant benefits for the Yukon, the Northwest Territories and the rest of Canada. Unresolved land claims are one of the challenges that has to be addressed for both Yukon and the Northwest Territories, as the proposed Alaska Highway Pipeline will travel through traditional territories of several Yukon first Nations. 1 tab., 4 figs

  14. Use of a geomorphological transfer function to model design floods in small hillside catchments in semiarid Tunisia

    Science.gov (United States)

    Nasri, S.; Cudennec, C.; Albergel, J.; Berndtsson, R.

    2004-02-01

    In the beginning of the 1990s, the Tunisian Ministry of Agriculture launched an ambitious program for constructing small hillside reservoirs in the northern and central region of the country. At present, more than 720 reservoirs have been created. They consist of small compacted earth dams supplied with a horizontal overflow weir. Due to lack of hydrological data and the area's extreme floods, however, it is very difficult to design the overflow weirs. Also, catchments are very sensitive to erosion and the reservoirs are rapidly silted up. Consequently, prediction of flood volumes for important rainfall events becomes crucial. Few hydrological observations, however, exist for the catchment areas. For this purpose a geomorphological model methodology is presented to predict shape and volume of hydrographs for important floods. This model is built around a production function that defines the net storm rainfall (portion of rainfall during a storm which reaches a stream channel as direct runoff) from the total rainfall (observed rainfall in the catchment) and a transfer function based on the most complete possible definition of the surface drainage system. Observed rainfall during 5-min time steps was used in the model. The model runoff generation is based on surface drainage characteristics which can be easily extracted from maps. The model was applied to two representative experimental catchments in central Tunisia. The conceptual rainfall-runoff model based on surface topography and drainage network was seen to reproduce observed runoff satisfactory. The calibrated model was used to estimate runoff from 5, 10, 20, and 50 year rainfall return periods regarding runoff volume, maximum runoff, as well as the general shape of the runoff hydrograph. Practical conclusions to design hill reservoirs and to extrapolate results using this model methodology for ungauged small catchments in semiarid Tunisia are made.

  15. Prediction of onset and cessation of austral summer rainfall and dry spell frequency analysis in semiarid Botswana

    Science.gov (United States)

    Byakatonda, Jimmy; Parida, B. P.; Kenabatho, Piet K.; Moalafhi, D. B.

    2018-01-01

    Uncertainties in rainfall have increased in the recent past exacerbating climate risks which are projected to be higher in semiarid environments. This study investigates the associated features of rainfall such as rain onset, cessation, length of the rain season (LRS), and dry spell frequency (DSF) as part of climate risk management in Botswana. Their trends were analysed using Mann-Kendall test statistic and Sen's Slope estimator. The rainfall-evapotranspiration relationships were used in formulating the rain onset and cessation criteria. To understand some of the complexities arising from such uncertainties, artificial neural network (ANN) is used to predict onset and cessation of rain. Results reveal higher coefficients of variation in onset dates as compared to cessation of rain. Pandamatenga experiences the earliest onset on 28th of November while Tsabong the latest on 14th of January. Likewise, earliest cessation is observed at Tshane on 22nd of February and the latest on 30th of March at Shakawe. The shortest LRS of 45 days is registered at Tsabong whereas the northern locations show LRS greater than 100 days. Stations across the country experience strong negative correlation between onset and LRS of - 0.9. DSF shows increasing trends in 50% of the stations but only significant at Mahalapye, Pandamatenga, and Shakawe. Combining the LRS criteria and DSF, Kasane, Pandamatenga, and Shakawe were identified to be suitable for rainfed agriculture in Botswana especially for short to medium maturing cereal varieties. Predictions of onset and cessation indicate the possibility of delayed onset by 2-5 weeks in the next 5 years. Information generated from this study could help Botswana in climate risk management in the context of rainfed farming.

  16. Soil fertility management strategies and practices by smallholder farmers in semi-arid areas of Zimbabwe

    NARCIS (Netherlands)

    Mapfumo, P.; Giller, K.E.

    2001-01-01

    Indigenous soil fertility management strategies in semi-arid Communal Areas of Zimbabwe have largely been driven by an extensive use of resources. The shrinking of common property resources (CPRs) due to expansion of cultivated lands, the general loss of productivity in natural ecosystems (e.g.,

  17. Beyond the desertification narrative: a framework for agricultural drought in semi-arid East Africa

    NARCIS (Netherlands)

    Slegers, M.F.W.; Stroosnijder, L.

    2008-01-01

    In the 20th century, much research was done on desertification. Desertification developed into a complex and vague construct that means land degradation under specific conditions. Projects focusing on land degradation in semiarid East Africa have met with limited success because farmers prioritize

  18. Cattle grazing in semiarid forestlands: Habitat selection during periods of drought

    Science.gov (United States)

    C. L. Roever; T. DelCurto; M. Rowland; M. Vavra; M. Wisdom

    2015-01-01

    Climate change models are predicting increased frequency and severity of droughts in arid and semiarid environments, and these areas are responsible for much of the world’s livestock production. Because cattle (Bos Taurus) grazing can impact the abundance, distribution, and ecological function of native plant and animal communities, it is important...

  19. Vegetation monitoring on semi-arid grasslands unglazed by domestic livestock

    Science.gov (United States)

    Linda Kennedy; Dan Robinett

    2013-01-01

    The Research Ranch is an 8000-acre sanctuary and research facility in the semi-arid grasslands of southeastern Arizona, USA. Cattle were removed from the property in 1968 to provide a reference area by which various land uses, such as grazing and exurbanization, could be evaluated. Vegetation transects were established in 2000 and 2003 on several ecological sites in...

  20. Coupled flow and salinity transport modelling in semi-arid environments

    DEFF Research Database (Denmark)

    Bauer-Gottwein, Peter; Held, R.J.; Zimmermann, S.

    2006-01-01

    Numerical groundwater modelling is used as the base for sound aquifer system analysis and water resources assessment. In many cases, particularly in semi-arid and arid regions, groundwater flow is intricately linked to salinity transport. A case in point is the Shashe River Valley in Botswana. A ...

  1. Runoff controlling factors in various sized catchments in a semi-arid Mediterranean environment in Spain

    NARCIS (Netherlands)

    Wit, A.M.W. de

    2001-01-01

    Understanding land degradation in a semi-arid Mediterranean environment is very difficult because of the contributing factors: precipitation, infiltration vegetation cover and discontinuity of flow and the temporal and spatial levels of resolution at which these factors are acting. Therefore it

  2. Catchment management in semi-arid area of central South Africa ...

    African Journals Online (AJOL)

    This accentuates the need for wise decisions by catchment management agencies (CMAs), especially in water-scarce semi-arid areas. ... A financial analysis also showed that gross margin of option, expressed as R/ m3 of rainwater utilised, was estimated to be between 0.0234 to 0.0254 under Option 1 and 0.0354 for ...

  3. Spatiotemporal soil and saprolite moisture dynamics across a semi-arid woody plant gradient

    Science.gov (United States)

    Woody plant cover has increased 10-fold over the last 140+ years in many parts of the semi-arid western USA. Woody plant cover can alter the timing and amount of plant available moisture in the soil and saprolite. To assess spatiotemporal subsurface moisture dynamics over two water years in a snow-d...

  4. Water scarcity under scenarios for global climate change and regional development in semiarid Northeastern Brazil

    NARCIS (Netherlands)

    de Araújo, José Carlos; Döll, Petra; Güntner, Andreas; Krol, Martinus S.; Rodrigues Abreu, Cláudia Beghini; Hauschild, Maike; Mendiondo, Eduardo Mario

    2004-01-01

    The State of Ceará, located in semiarid Northeastern Brazil, suffers under irregularly recurring droughts that go along with water scarcity. Structural policies to control and reduce water scarcity, as water supply and demand management, should be seen as long-term planning, and thus have to

  5. Contour hedgerows and grass strips in erosion and runoff control in semi-arid Kenya

    NARCIS (Netherlands)

    Kinama, J.M.; Stigter, C.J.; Ong, C.K.; Ng'ang'a, J.K.; Gichuki, F.N.

    2007-01-01

    Most early alley cropping studies in semi-arid Kenya were on fairly flat land while there is an increase in cultivated sloping land. The effectiveness of aging contour hedgerows and grass strips for erosion control on an about 15% slope of an Alfisol was compared. The five treatments were Senna

  6. Soil water retention as affected by tillage and residue management in semiarid Spain

    NARCIS (Netherlands)

    Bescansa, P.; Imaz, M.J.; Virto, I.; Enrique, A.; Hoogmoed, W.B.

    2006-01-01

    Conservation tillage preserves soil water and this has been the main reason for its rapid dissemination in rainfed agriculture in semiarid climates. We determined the effects of conservation versus conventional tillage on available soil water capacity (AWC) and related properties at the end of 5

  7. Hydrological modeling in semi-arid region using HEC-HMS model ...

    African Journals Online (AJOL)

    The purpose of this study is to simulate rainfall-runoff in the semi-arid region of ... the frequency storm is used for the meteorological model, the SCS curve number is ... SCS unit hydrograph method have been applied to simulate the runoff rate.

  8. An automated microlysimeter to study dew formation and evaporation in arid and semiarid regions

    NARCIS (Netherlands)

    Heusinkveld, B.G.; Berkowicz, S.M.; Jacobs, A.F.G.; Holtslag, A.A.M.; Hillen, W.C.A.M.

    2006-01-01

    The development of a simple and low-cost portable weighing microlysimeter that makes use of a load cell for automated recording and for studying daily dew formation, rate of accumulation, and subsequent evaporation in arid or semiarid regions during rainless seasons is presented. The sampling cup is

  9. Preface paper to the Semi-Arid Land-Surface-Atmosphere (SALSA) Program special issue

    Science.gov (United States)

    Goodrich, D.C.; Chehbouni, A.; Goff, B.; MacNish, B.; Maddock, T.; Moran, S.; Shuttleworth, W.J.; Williams, D.G.; Watts, C.; Hipps, L.H.; Cooper, D.I.; Schieldge, J.; Kerr, Y.H.; Arias, H.; Kirkland, M.; Carlos, R.; Cayrol, P.; Kepner, W.; Jones, B.; Avissar, R.; Begue, A.; Bonnefond, J.-M.; Boulet, G.; Branan, B.; Brunel, J.P.; Chen, L.C.; Clarke, T.; Davis, M.R.; DeBruin, H.; Dedieu, G.; Elguero, E.; Eichinger, W.E.; Everitt, J.; Garatuza-Payan, J.; Gempko, V.L.; Gupta, H.; Harlow, C.; Hartogensis, O.; Helfert, M.; Holifield, C.; Hymer, D.; Kahle, A.; Keefer, T.; Krishnamoorthy, S.; Lhomme, J.-P.; Lagouarde, J.-P.; Lo, Seen D.; Luquet, D.; Marsett, R.; Monteny, B.; Ni, W.; Nouvellon, Y.; Pinker, R.; Peters, C.; Pool, D.; Qi, J.; Rambal, S.; Rodriguez, J.; Santiago, F.; Sano, E.; Schaeffer, S.M.; Schulte, M.; Scott, R.; Shao, X.; Snyder, K.A.; Sorooshian, S.; Unkrich, C.L.; Whitaker, M.; Yucel, I.

    2000-01-01

    The Semi-Arid Land-Surface-Atmosphere Program (SALSA) is a multi-agency, multi-national research effort that seeks to evaluate the consequences of natural and human-induced environmental change in semi-arid regions. The ultimate goal of SALSA is to advance scientific understanding of the semi-arid portion of the hydrosphere-biosphere interface in order to provide reliable information for environmental decision making. SALSA approaches this goal through a program of long-term, integrated observations, process research, modeling, assessment, and information management that is sustained by cooperation among scientists and information users. In this preface to the SALSA special issue, general program background information and the critical nature of semi-arid regions is presented. A brief description of the Upper San Pedro River Basin, the initial location for focused SALSA research follows. Several overarching research objectives under which much of the interdisciplinary research contained in the special issue was undertaken are discussed. Principal methods, primary research sites and data collection used by numerous investigators during 1997-1999 are then presented. Scientists from about 20 US, five European (four French and one Dutch), and three Mexican agencies and institutions have collaborated closely to make the research leading to this special issue a reality. The SALSA Program has served as a model of interagency cooperation by breaking new ground in the approach to large scale interdisciplinary science with relatively limited resources.

  10. Agroforestry parkland species diversity : uses and management in semi-arid West-Africa (Burkina Faso)

    NARCIS (Netherlands)

    Nikiema, A.

    2005-01-01

    Agroforestry parkland in semi-arid West Africa is a rural land use system, which allows farmers to grow annual crops in combination with useful trees. In addition to cereals, tree products such as vegetables, fruits, vegetable oil, firewood, fodder, and medicines are obtained from the parklands.

  11. Energetics of the green iguana (Iguana iguana) in a semi-arid environment

    OpenAIRE

    van Marken Lichtenbelt, Wouter David

    1991-01-01

    Energy budgets in the herbivorous green iguana (Iguana Iguana) were studied from April 1985-October 1988 in a strongly seasonal environment on the semi-arid island Curacao (Netherlands Antilles) under the auspices of the CARMABI Foundation in cooperation with the State University of Groningen (The Netherlands). ... Zie: Summary

  12. Energetics of the green iguana (Iguana iguana) in a semi-arid environment

    NARCIS (Netherlands)

    van Marken Lichtenbelt, Wouter David

    1991-01-01

    Energy budgets in the herbivorous green iguana (Iguana Iguana) were studied from April 1985-October 1988 in a strongly seasonal environment on the semi-arid island Curacao (Netherlands Antilles) under the auspices of the CARMABI Foundation in cooperation with the State University of Groningen (The

  13. Evaluating rainwater harvesting systems in arid and semi-arid regions

    NARCIS (Netherlands)

    Ammar, Adham Ali

    2017-01-01

    Rainwater harvesting (RWH) is an ancient traditional technology practised in many parts of the world, especially in arid and semi-arid regions (ASARs). ASARs represent 40% of the earth’s land surface and are characterised by low average annual rainfall and uneven temporal and spatial

  14. Recovery of rangelands : the functioning of soil seed banks in a semi-arid African savanna

    NARCIS (Netherlands)

    Tessema, Z.K.

    2011-01-01

    Rangelands in Africa provide important forage resources for herbivores; particularly perennial grasses provide grazing for domestic and wild herbivores. However, semi-arid African rangelands experience severe vegetation and soil degradation due to heavy grazing, causing negative impacts

  15. Beekeeping technology adoption in arid and semi-arid lands of ...

    African Journals Online (AJOL)

    This study was conducted in Kibwezi Sub-County, south eastern Kenya. This is a typical semiarid area and beekeeping is a major economic activity. Although various beekeeping technologies have been available in the study area for many decades, information on the effect of these technologies on the production levels of ...

  16. Integrated water and nutrient management for sorghum production in semi-arid Burkina Faso

    NARCIS (Netherlands)

    Zougmoré, R.

    2003-01-01

    Loss of water and nutrients through runoff are major agriculture problems for inherent poor fertile soils in semiarid West Africa. The intensification of crop production requires an integration of soil, water and nutrient management that is locally acceptable and beneficial for smallholder farmers.

  17. Extensive Green Roof Species and Soilless Media Evaluations in Semi-arid Colorado

    Science.gov (United States)

    In the high elevation, semi-arid climate of Colorado, green roofs have not been scientifically tested. This research examined alternative plant species, soilless media blends and plant interactions on an existing, modular-extensive (shallow, 10 cm deep) green roof in Denver, Colo...

  18. Infiltration and planting pits for improved water management and maize yield in semi-arid Zimbabwe

    NARCIS (Netherlands)

    Nyakudya, I.W.; Stroosnijder, L.; Nyagumbo, I.

    2014-01-01

    Realising that rainwater harvesting (RWH) improves crop productivity, smallholder farmers in semi-arid Zimbabwe modified contour ridges traditionally used for rainwater management by digging infiltration pits inside contour ridge channels in order to retain more water in crop fields. However,

  19. Growth and yield performance of Jerusalem artichoke clones in a semiarid region of China

    NARCIS (Netherlands)

    Liu, Z.X.; Spiertz, J.H.J.; Sha, J.; Xue, S.; Xie, G.H.

    2012-01-01

    This study investigated biomass yield and growth characteristics of 26 Jerusalem artichoke (Helianthus tuberosus L.) clones and assessed it as a bioenergy crop for a semiarid region of the Loess Plateau in China. Genotype, year, and genotype ´ year interaction contributed to differences in crop

  20. 1 Title page Title: Groundwater quality in a semi-arid region of India ...

    Indian Academy of Sciences (India)

    64

    Groundwater quality in a semi-arid region of India - suitability for drinking, ... concentration ranges from 0.1 to 4.4 mg/L and 39% of the total samples measured ..... on identifying local priorities and implementing proper management is very.

  1. Prescribed fire, soil inorganic nitrogen dynamics, and plant responses in a semiarid grassland

    Science.gov (United States)

    David J. Augustine; Paul Brewer; Dana M. Blumenthal; Justin D. Derner; Joseph C. von Fischer

    2014-01-01

    In arid and semiarid ecosystems, fire can potentially affect ecosystem dynamics through changes in soil moisture, temperature, and nitrogen cycling, as well as through direct effects on plant meristem mortality. We examined effects of annual and triennial prescribed fires conducted in early spring on soil moisture, temperature, and N, plant growth, and plant N content...

  2. Woody plants in agro-ecosystems of semi-arid regions

    NARCIS (Netherlands)

    Breman, H.; Kessler, J.J.

    1995-01-01

    A quantitative analysis of the role of woody plants in semi-arid regions, focusing on the Sahel and Sudan zones in West-Africa, is given for the assessment of their benefits in agro-sylvopastoral land-use systems with productive and sustainability objectives.

  3. Soil moisture prediction to support management in semiarid wetlands during drying episodes

    NARCIS (Netherlands)

    Aguilera, Héctor; Moreno, Luis; Wesseling, Jan G.; Jiménez-Hernández, María E.; Castaño, Silvino

    2016-01-01

    Wetlands supported by groundwater in semiarid regions are extremely vulnerable to the impacts of droughts, particularly anthropized systems. During drying periods, soil water content arises as the controlling factor for environmental and ecological disturbances such as the spread of invasive

  4. Characterisation of rainfall at a semi-arid ecotope in the Limpopo ...

    African Journals Online (AJOL)

    Detailed knowledge of rainfall regime is an important prerequisite for agricultural planning. Despite the importance of rain-fed agriculture to food security in the semi-arid regions of South Africa, studies to understand the spatial and temporal variability of rainfall are not widely documented. Twenty-three years (1983 to 2005) ...

  5. Nuclear applications for the management of aquifers in the semi-arid region

    International Nuclear Information System (INIS)

    Simoes Filho, Fernando Lamego

    2005-01-01

    The semi-arid region of the Northeast of Brazil is characterized by a lack of superficial waters due to the low pluviometric precipitation and high evaporation rates. In addition to this, the precipitation events are irregular in time causing long periods of dryness or flooding with catastrophic consequences. Owing to adverse climatic conditions with recurrent droughts, intense pressure is being put on the use of groundwater resources. Groundwater occurrence on its turn depends on a series of geological and climatological characteristics that are very variable in the region. Because of this situation, groundwater is of strategical importance and represents a vital factor to its socioeconomic development. However, there is still insufficient knowledge of the basic aquifers characteristics leading to an over exploitation of the water resources. It is not surprising that, amongst other reasons, this situation contributes to the fact that areas with the lowest human development pattern are located in the semi-arid region of Brazil. Given the nature of hydrological problems that need to be addressed in semi-arid regions, nuclear/isotope techniques are increasingly recognized as indispensable tools for water resources assessment and development. However, information arising from these techniques has to cope with other hydrological methods in an integrated manner. The general objective was prospect nuclear technologies as tools for aquifer management, promoting sustainable use of groundwater in the semi-arid region. (author)

  6. Effects of irrigation and plastic mulch on soil properties on semi-arid abandoned fields

    NARCIS (Netherlands)

    van der Meulen, E.S.; Nol, L.; Cammeraat, L.H.

    2006-01-01

    The Guadalentín Basin in Spain is one of the driest areas of Europe and has problems with high evaporation rates, and high risks of desertification exist including soil quality loss and soil erosion. Farmers in this semi-arid region use polyethylene covers on their irrigated croplands to reduce

  7. Understanding hydrological variability for improved water management in the Semi-Arid Karkheh basin, Iran

    NARCIS (Netherlands)

    Masih, I.

    2011-01-01

    This study provides a hydrology based assessment of (surface) water resources and its continuum of variability and change at different spatio-temporal scales in the semi-arid Karkheh Basin, Iran, where water is scarce, competition among users is high and massive water resources development is under

  8. Polyacrylamide molecular weight and phosphogypsum effects on infiltration and erosion in semi-arid soils

    Science.gov (United States)

    Seal formation at the surface of semi-arid soils during rainstorms reduces soil infiltration rate (IR) and causes runoff and erosion. Surface application of dry anionic polyacrylamide (PAM) with high molecular weight (MW) has been found to be effective in stabilizing soil aggregates, and decreasing ...

  9. The Soil-Land use System in a Sand Spit Area in the Semi-Arid ...

    African Journals Online (AJOL)

    The Soil-Land use System in a Sand Spit Area in the Semi-Arid Coastal Savanna Region of Ghana – Development, Sustainability and Threats. ... The investigation comprises soil profile descriptions and analyses on the dominant soil type on the sand spit, measurement of electrical conductivity of well water and in the soil, ...

  10. Soil quality improvement for crop production in semi-arid West Africa

    NARCIS (Netherlands)

    Ouédraogo, E.

    2004-01-01

    Soil quality maintenance and crop production improvement in semi-arid West Africa require appropriate cropping technologies, which are ecologically sound and economically viable. Thus, on-farm and on-station experiments have been carried out on the central plateau and in the south of Burkina Faso

  11. Sustainable semiarid dryland production in relation to tillage effects on Hydrology: 1983-2013

    Science.gov (United States)

    Semiarid dryland crop yields with no-till, NT, residue management are often greater than stubble-mulch tillage, SM, as a result of improved soil conditions or water conservation, but knowledge of long-term tillage effects on the comprehensive field hydrology and sustained crop production is needed. ...

  12. Semi-arid Northeast Brazil: integrated modelling of regional development and global change impacts

    NARCIS (Netherlands)

    Krol, Martinus S.; Fuhr, Dagmar; Döring, Andreas; Unruh, Jon D.; Krol, Maarten S.; Kliot, Nurit

    2004-01-01

    Societies in semi-arid areas in developing regions are amongst those most vulnerable to climate variability and potentially most vulnerable to climate change. The vulnerability to climate variability emerges from a combination of the level of availability of natural resources and the human

  13. Integrated Scenarios of Regional Development in Two Semi-Arid States of North-Eastern Brazil

    NARCIS (Netherlands)

    Döll, Petra; Krol, Martinus S.

    2002-01-01

    Scenario analysis of the future is an important tool for supporting sustainability-oriented regional planning. To assist regional planning in two federal states in semi-arid North-eastern Brazil, Ceará and Piauí, we developed integrated qualitative¿quantitative scenarios that show potential

  14. Evaluation of methods for delineating riparian zones in a semi-arid montane watershed

    Science.gov (United States)

    Jessica A. Salo; David M. Theobald; Thomas C. Brown

    2016-01-01

    Riparian zones in semi-arid, mountainous regions provide a disproportionate amount of the available wildlife habitat and ecosystem services. Despite their importance, there is little guidance on the best way to map riparian zones for broad spatial extents (e.g., large watersheds) when detailed maps from field data or high-resolution imagery and terrain data...

  15. Simulated biomass, environmental impacts and best management practices for long-term switchgrass systems in a semi-arid region

    International Nuclear Information System (INIS)

    Wang, Limei; Qian, Yaling; Brummer, Joe E.; Zheng, Jiyong; Wilhelm, Sarah; Parton, William J.

    2015-01-01

    Long-term information on switchgrass (Panicum virgatum L.) as a biomass energy crop grown on marginally saline soil and the associated impacts on soil carbon (C) and nitrogen (N) dynamics, greenhouse gas (GHG) emissions, and best management practices (BMPs) are limited. In this study, we employed the DAYCENT model, based on a 4-year switchgrass field experiment, to evaluate the long-term biomass yield potential and environmental impacts, and further to develop BMPs for switchgrass in a semi-arid region. The model showed that long-term (14-year) annual mean biomass yields were 9.6 and 5.2 Mg ha −1 for irrigated and rainfed switchgrass systems, respectively. The simulated biomass yields correlated well with field-measured biomass with r 2 values of 0.99 and 0.89 for irrigated and rainfed systems, respectively. Soil organic carbon (SOC) and soil total nitrogen (STN) accumulated rapidly after switchgrass establishment, with mean accrual rates of 0.99–1.13 Mg C ha −1  yr −1 and 0.04–0.08 Mg N ha −1  yr −1 , respectively. Based on the outputs of numerous long-term model simulations with variable irrigation water supplies and N rates, the irrigation regime and N rate with the highest yield to input ratio were chosen as BMPs. The DAYCENT model predicted-BMP was irrigating every 14 days at 70% potential evapotranspiration combined with an N rate of 67 kg ha −1  yr −1 . Switchgrass established and produced biomass reasonably well in this semi-arid region; however, appropriate irrigation and N fertilization were needed for optimal biomass yield. Switchgrass had a great potential to sequester C into soils with low N 2 O emissions while supplying significant quantities of biomass for biofuel synthesis. - Highlights: • The DAYCENT model reliably simulated the growth of switchgrass on marginal land. • Long-term biomass and environmental impacts were simulated using the DAYCENT model. • Switchgrass produced biomass well on marginal land, but

  16. Phytogeographical patterns of dry forests sensu stricto in northern Minas Gerais State, Brazil.

    Science.gov (United States)

    Arruda, Daniel M; Ferreira-Júnior, Walnir G; Duque-Brasil, Reinaldo; Schaefer, Carlos E R

    2013-01-01

    The Deciduous Complex that occurs in northern Minas Gerais State, Brazil, raises questions about the floristic affinities of these formations in relation to neighboring phytogeographical domains. Little is known about the identity of the seasonal forest formations that comprise this complex, or about its relationships to abiotic components, such as soils, topography and climate. This study aimed to recognize the patterns of floristic similarity of all studied fragments of dry forest of northern Minas Gerais with soil and climate attributes, based on the available database. Cluster analysis indicated the existence of two floristic groups that had clear associations with either the Koppen's BSh (semi-arid) or Aw (seasonal tropical) climates. Likewise, the subdivisions of these groups showed clear associations with the dominant soil classes in the region. The Red-Yellow Latosol is the dominant soil classes in the BSh climatic domain, seconded by alluvial areas associated with Fluvic Neosols. The Aw domain comprised a much varied set of soils: Nitosols, Argisols, Cambisols and Litholic Neosols, most derived from the Bambuí limestone/slate formation. The ecotonal nature of northern Minas Gerais State provides a complex interaction between the flora of neighboring phytogeographical domains. This, allied to pedogeomorphological factors, allowed a better understanding of the effects of late Quaternary climate changes for the Deciduous Complex evolution. We conclude that the Latosols under present-day semi-arid climates (BSh) are relicts of former wetter climates, during which humid forest (semideciduous) expansion took place. Later, these semideciduous forests were subjected to a much drier climate, when selection for deciduousness led to the present-days Deciduous Complex scenario.

  17. Microbial Community Activity And Plant Biomass Are Insensitive To Passive Warming In A Semiarid Ecosystem

    Science.gov (United States)

    Espinosa, N. J.; Fehmi, J. S.; Rasmussen, C.; Gallery, R. E.

    2017-12-01

    Soil microorganisms drive biogeochemical and nutrient cycling through the production of extracellular enzymes that facilitate organic matter decomposition and the flux of large amounts of carbon dioxide to the atmosphere. Although dryland ecosystems occupy over 40% of land cover and are projected to expand due to climate change, much of our current understanding of these processes comes from mesic temperate ecosystems. Understanding the responses of these globally predominant dryland ecosystems is therefore important yet complicated by co-occurring environmental changes. For example, the widespread and pervasive transition from grass to woody dominated landscapes is changing the hydrology, fire regimes, and carbon storage potential of semiarid ecosystems. In this study, we used a novel passive method of warming to conduct a warming experiment with added plant debris as either woodchip or biochar, to simulate different long-term carbon additions that accompany woody plant encroachment in semiarid ecosystems. The response of heterotrophic respiration, plant biomass, and microbial activity was monitored bi-annually. We hypothesized that the temperature manipulations would have direct and indirect effects on microbial activity. Warmer soils directly reduce the activity of soil extracellular enzymes through denaturation and dehydration of soil pores and indirectly through reducing microbe-available substrates and plant inputs. Overall, reduction in extracellular enzyme activity may reduce decomposition of coarse woody debris and potentially enhance soil carbon storage in semiarid ecosystems. For all seven hydrolytic enzymes examined as well as heterotrophic respiration, there was no consistent or significant response to experimental warming, regardless of seasonal climatic and soil moisture variation. The enzyme results observed here are consistent with the few other experimental results for warming in semiarid ecosystems and indicate that the controls over soil

  18. Differential nitrogen cycling in semiarid sub-shrubs with contrasting leaf habit.

    Directory of Open Access Journals (Sweden)

    Sara Palacio

    Full Text Available Nitrogen (N is, after water, the most limiting resource in semiarid ecosystems. However, knowledge on the N cycling ability of semiarid woody plants is still very rudimentary. This study analyzed the seasonal change in the N concentrations and pools of the leaves and woody organs of two species of semiarid sub-shrubs with contrasting leaf habit. The ability of both species to uptake, remobilize and recycle N, plus the main storage organ for N during summer drought were evaluated. We combined an observational approach in the field with experimental (15N labelling of adult individuals grown in sand culture. Seasonal patterns of N concentrations were different between species and organs and foliar N concentrations of the summer deciduous Lepidium subulatum were almost double those of the evergreen Linum suffruticosum. L. subulatum up took ca. 60% more external N than the evergreen and it also had a higher N resorption efficiency and proficiency. Contrastingly, L. suffruticosum relied more on internal N remobilization for shoot growth. Differently to temperate species, the evergreen stored N preferentially in the main stem and old trunks, while the summer deciduous stored it in the foliage and young stems. The higher ability of L. subulatum to uptake external N can be related to its ability to perform opportunistic growth and exploit the sporadic pulses of N typical of semiarid ecosystems. Such ability may also explain its high foliar N concentrations and its preferential storage of N in leaves and young stems. Finally, L. suffruticosum had a lower ability to recycle N during leaf senescence. These strategies contrast with those of evergreen and deciduous species from temperate and boreal areas, highlighting the need of further studies on semiarid and arid plants.

  19. The heart and great vessels

    International Nuclear Information System (INIS)

    Condon, V.

    1985-01-01

    Heart disease is the fifth most common cause of death in infants and children (preceded by anoxic and hypoxic conditions, gross congenital malformations, accidental death, and immaturity). Of all the cardiac lesions, congenital heart disease (CHD) makes up the gross majority, accounting for approximately 90% of all cardiac deaths. Approximately two-thirds of all infants who die from CHD do so within the first year of life; of these, approximately one-third die within the first month. The most common cause of death in the first month is hypoplastic left heart syndrome and lesions associated with it, i.e., aortic atresia/critical aortic stenosis and mitral atresia/critical mitral stenosis. Severe coarctation of the aorta (coarctation syndrome) and transposition of the great arteries are the other most important causes of death in this age group. CHD occurs as a familial condition in approximately 1-4% of cases; ventricular septal defects, patent ductus arteriosus, and atrial septal defect are particularly common forms. Parental age plays an important role, with a significantly increased risk of CHD in infants of mothers over 39 years of age. Patent ductus arteriosus is more prevalent in firstborn children, particularly those born prematurely to young mothers. Environmental factors, such as exposure to teratogenic agents, have also been shown to increase the incidence of CHD. Children with various syndromes also have increased incidence of CHD. Down syndrome is a classic example, as are other trisomies

  20. Tipping Points, Great and Small

    Science.gov (United States)

    Morrison, Foster

    2010-12-01

    The Forum by Jordan et al. [2010] addressed environmental problems of various scales in great detail, but getting the critical message through to the formulators of public policies requires going back to basics, namely, that exponential growth (of a population, an economy, or most anything else) is not sustainable. When have you heard any politician or economist from anywhere across the ideological spectrum say anything other than that more growth is essential? There is no need for computer models to demonstrate “limits to growth,” as was done in the 1960s. Of course, as one seeks more details, the complexity of modeling will rapidly outstrip the capabilities of both observation and computing. This is common with nonlinear systems, even simple ones. Thus, identifying all possible “tipping points,” as suggested by Jordan et al. [2010], and then stopping just short of them, is impractical if not impossible. The main thing needed to avoid environmental disasters is a bit of common sense.

  1. Estratégias na suplementação de vacas leiteiras no semi-árido do Brasil Strategies for the supplementation of dairy cows in the Brazilian semi-arid

    Directory of Open Access Journals (Sweden)

    Marcelo de Andrade Ferreira

    2009-07-01

    Full Text Available A região semi-árida do Brasil prolonga-se por uma área de 928 km² abrangendo uma parte do norte dos estados de Minas Gerais e Espírito Santo, os sertões da Bahia, Sergipe, Alagoas, Pernambuco, Paraíba, Rio Grande do Norte, Ceará e Piauí e mais 45 municípios do sudeste do Maranhão. A população é predominantemente rural e a ocupação principal de sua força de trabalho é a agropecuária. A pecuária leiteira aparece como uma das poucas opções nas regiões semi-áridas, principalmente no nordeste do Brasil, onde a alimentação dos rebanhos fundamenta-se na utilização de forrageiras cultivadas e no uso da vegetação nativa, predominantemente a caatinga, aspecto que imprime características estacionais à produção nesta região. A escassez e irregularidade acentuada na distribuição de chuvas, tanto no tempo quanto no espaço, com a ocorrência de longos períodos de estiagem, praticamente, determina a obrigatoriedade de suplementação de vacas leiteiras nos sistemas de produções em regiões semi-áridas do Brasil.Desta forma, a suplementação tem se baseado na utilização de recursos forrageiros adaptados à seca, co- produtos e resíduos da agroindústria local e em alimentos concentrados. Algumas alternativas têm sido utilizadas pelos produtores na tentativa de reduzir custos sem perder produtividade nos períodos de estiagem. Para superar as adversidades alguns sistemas de produção têm sido propostos como o CBL (Caatinga-buffel-leucena e o Sistema Glória. Além desses sistemas mencionados anteriormente, merecem destaque a utilização de co-produtos agroindustriais, restos de cultura, além de forrageiras nativas e adaptadas. Neste aspecto, a palma forrageira (Opuntia fícus indica- Mill merece atenção especial pela sua grande adaptação, valor nutritivo e produtividade.The Brazilian semi-arid region has 928 km² ranging from the northern portion of Minas Gerais and Espirito Santo States, the semi-arid lands

  2. Isolating and Quantifying the Effects of Climate and CO2 Changes (1980–2014 on the Net Primary Productivity in Arid and Semiarid China

    Directory of Open Access Journals (Sweden)

    Xia Fang

    2017-02-01

    Full Text Available Although the net primary productivity (NPP of arid/semiarid ecosystem is generally thought to be controlled by precipitation, other factors like CO2 fertilization effect and temperature change may also have important impacts, especially in the cold temperate areas of the northern China, where significant warming was reported in the recent decades. However, the impacts of climate and atmospheric CO2 changes to the NPP dynamics in the arid and semiarid areas of China (ASA-China is still unclear, hindering the development of climate adaptation strategy. Based on numeric experiments and factorial analysis, this study isolated and quantified the effects of climate and CO2 changes between 1980–2014 on ASA-China’s NPP, using the Arid Ecosystem Model (AEM that performed well in predicting ecosystems’ responses to climate/CO2 change according to our evaluation based on 21 field experiments. Our results showed that the annual variation in NPP was dominated by changes in precipitation, which reduced the regional NPP by 10.9 g·C/(m2·year. The precipitation-induced loss, however, has been compensated by the CO2 fertilization effect that increased the regional NPP by 14.9 g·C/(m2·year. The CO2 fertilization effect particularly benefited the extensive croplands in the Northern China Plain, but was weakened in the dry grassland of the central Tibetan Plateau due to suppressed plant activity as induced by a drier climate. Our study showed that the climate change in ASA-China and the ecosystem’s responses were highly heterogeneous in space and time. There were complex interactive effects among the climate factors, and different plant functional types (e.g., phreatophyte vs. non-phreatophyte could have distinct responses to similar climate change. Therefore, effective climate-adaptive strategies should be based on careful analysis of local climate pattern and understanding of the characteristic responses of the dominant species. Particularly, China

  3. Resolution VII International Conference Working Group on Birds of Prey of Northern Eurasia “Birds of Prey of Northern Eurasia: Problems and Adaptation Under Modern Conditions”

    Directory of Open Access Journals (Sweden)

    Igor V. Karyakin

    2017-01-01

    Full Text Available From 19 to 24 September, 2016 VII International Conference of the Working Group on Raptors of Northern Eurasia “Birds of prey of Northern Eurasia: problems and adaptation under modern conditions” was held on the basis of the Sochi National Park. Materials for the conference were presented by 198 ornithologists from Russia, Ukraine, Belarus, Kazakhstan, Moldova, Turkmenistan, Austria, Great Britain, Hungary, Mongolia, Poland, Estonia and the USA, who published 148 articles in two collections “Birds of prey of Northern Eurasia” and “Palearctic Harriers”.

  4. Northern Pintail Telemetry [ds231

    Data.gov (United States)

    California Natural Resource Agency — Using radio-telemetry, female northern pintail (Anas acuta) survival, distribution, and movements during late August-March in Central California were determined...

  5. Transposition of the great arteries

    Directory of Open Access Journals (Sweden)

    Castela Eduardo

    2008-10-01

    Full Text Available Abstract Transposition of the great arteries (TGA, also referred to as complete transposition, is a congenital cardiac malformation characterised by atrioventricular concordance and ventriculoarterial (VA discordance. The incidence is estimated at 1 in 3,500–5,000 live births, with a male-to-female ratio 1.5 to 3.2:1. In 50% of cases, the VA discordance is an isolated finding. In 10% of cases, TGA is associated with noncardiac malformations. The association with other cardiac malformations such as ventricular septal defect (VSD and left ventricular outflow tract obstruction is frequent and dictates timing and clinical presentation, which consists of cyanosis with or without congestive heart failure. The onset and severity depend on anatomical and functional variants that influence the degree of mixing between the two circulations. If no obstructive lesions are present and there is a large VSD, cyanosis may go undetected and only be perceived during episodes of crying or agitation. In these cases, signs of congestive heart failure prevail. The exact aetiology remains unknown. Some associated risk factors (gestational diabetes mellitus, maternal exposure to rodenticides and herbicides, maternal use of antiepileptic drugs have been postulated. Mutations in growth differentiation factor-1 gene, the thyroid hormone receptor-associated protein-2 gene and the gene encoding the cryptic protein have been shown implicated in discordant VA connections, but they explain only a small minority of TGA cases. The diagnosis is confirmed by echocardiography, which also provides the morphological details required for future surgical management. Prenatal diagnosis by foetal echocardiography is possible and desirable, as it may improve the early neonatal management and reduce morbidity and mortality. Differential diagnosis includes other causes of central neonatal cyanosis. Palliative treatment with prostaglandin E1 and balloon atrial septostomy are usually

  6. Analysis of benthic macroinvertebrates and biotic indices to evaluate water quality in rivers impacted by mining activities in northern Chile

    Directory of Open Access Journals (Sweden)

    Alvial I.E.

    2013-02-01

    Full Text Available Catchments in the semiarid regions are especially susceptible to environmental perturbation associated with water scarcity, hydrological variations and overuse by anthropogenic activities. Using multivariate analysis to relate environmental and biological data, and diversity and biotic indices (ChBMWP, ChIBF, we analyzed the macroinvertebrate composition of 12 rivers of the semiarid region of northern Chile. A non-metric multidimensional scaling for macroinvertebrate taxa and a principal component analysis for environmental variables strongly separated upstream sites (e.g. Vacas Heladas and Malo Rivers, which presented low pH and high dissolved metal concentrations, from other sites. Effectively, CCA showed that metals and low pH, associated with the altitudinal gradient, determined the distributional patterns of macroinvertebrates in the Elqui catchment. The causes of these particular conditions could be related to geological processes and human impact. The biotic indices applied to the sampling sites corroborated and reflected these characteristics, with La Laguna and Turbio Rivers showing a diverse macroinvertebrate community and moderate to good water quality, and the Claro River showing favorable conditions for the development of aquatic biota, indicating its better quality relative to other stations. To the middle and low part of the basin, a change in the composition of the community was observed, with species that suggest an impact by an increase in organic matter, due to agricultural activities and urban settlements concentrated in this area. Our results suggest that macroinvertebrate taxa in northern Chile may be exceptional species, adapted to unfavorable geochemical conditions, and emphasize the need for protection of the semiarid basins of the region.

  7. Growth-climate relationships across topographic gradients in the northern Great Lakes

    Science.gov (United States)

    S.F. Dymond; A.W. D' Amato; Randy Kolka; P.V. Bolstad; Stephen Sebestyen; J.B. Bradford

    2016-01-01

    Climatic conditions exert important control over the growth, productivity, and distribution of forests, and characterizing these relationships is essential for understanding how forest ecosystems will respond to climate change. We used dendrochronological methods to develop climate–growth relationships for two dominant species, Populus tremuloides...

  8. Perennial forbs for wildlife habitat restoration on mined lands in the northern Great Plains

    Science.gov (United States)

    Ardell J. Bjugstad; Warren C. Whitman

    1982-01-01

    Research was designed to assess the establishment and growth potential of 30 perennial forbs by seeding and/or transplanting them on coal mine spoil materials over a 2-year period. Five species showed exceptional emergence and vigorous growth from direct seeding. Six species showed vigorous growth with the use of transplanted plants. Seeding resulted in successful...

  9. Importance of agricultural landscapes to nesting burrowing owls in the Northern Great Plains, USA

    Science.gov (United States)

    Restani, M.; Davies, J.M.; Newton, W.E.

    2008-01-01

    Anthropogenic habitat loss and fragmentation are the principle factors causing declines of grassland birds. Declines in burrowing owl (Athene cunicularia) populations have been extensive and have been linked to habitat loss, primarily the decline of black-tailed prairie dog (Cynomys ludovicianus) colonies. Development of habitat use models is a research priority and will aid conservation of owls inhabiting human-altered landscapes. From 2001 to 2004 we located 160 burrowing owl nests on prairie dog colonies on the Little Missouri National Grassland in North Dakota. We used multiple linear regression and Akaike's Information Criterion to estimate the relationship between cover type characteristics surrounding prairie dog colonies and (1) number of owl pairs per colony and (2) reproductive success. Models were developed for two spatial scales, within 600 m and 2,000 m radii of nests for cropland, crested wheatgrass (Agropyron cristatum), grassland, and prairie dog colonies. We also included number of patches as a metric of landscape fragmentation. Annually, fewer than 30% of prairie dog colonies were occupied by owls. None of the models at the 600 m scale explained variation in number of owl pairs or reproductive success. However, models at the 2,000 m scale did explain number of owl pairs and reproductive success. Models included cropland, crested wheatgrass, and prairie dog colonies. Grasslands were not included in any of the models and had low importance values, although percentage grassland surrounding colonies was high. Management that protects prairie dog colonies bordering cropland and crested wheatgrass should be implemented to maintain nesting habitat of burrowing owls. ?? 2008 Springer Science+Business Media B.V.

  10. Distribution, Abundance and Population Structuring of Beaked Wales in the Great Bahama Canyon, Northern Bahamas

    Science.gov (United States)

    2012-09-02

    Jatanon On« laafaaa» Sur» 1204 AitngJon VA 222Q2^S0T Raapondanto ahoutf til provrwor oi la» no parw thai be vjbfgct to an» panaWy «or taanq to comply...Providence Channel NW Atlantic Octan NE Providence Channel Cul de Sec • « tea i * i«1 a Figure 2. Equal-angle line transects were run in four

  11. Homogenization of northern U.S. Great Lakes forests due to land use

    Science.gov (United States)

    Lisa A. Schulte; David J. Mladenoff; Thomas R. Crow; Laura C. Merrick; David T. Cleland

    2007-01-01

    Human land use of forested regions has intensified worldwide in recent decades, threatening long-term sustainability. Primary effects include conversion of land cover or reversion to an earlier stage of successional development. Both types of change can have cascading effects through ecosystems; however, the longterm effects where forests are allowed to regrow are...

  12. RELATIONSHIPS BETWEEN COMPETITIVENESS IN THE NORTHERN GREAT PLAIN AND THE ORGANISATIONAL CULTURE OF LOCAL AUTHORITIES

    OpenAIRE

    Matko, Andrea Emese; Berde, Csaba

    2012-01-01

    One of the five basic factors in the Lengyel-type pyramid model – institutions and social capital – is essential in the economic growth of the region. Economic success however, does not only depend on participants in the economy, but on social factors such as the roles played by local authorities, including their functions, operation and organisational culture, all of which are crucial factors. Based on the results obtained regarding organisational culture it can be stated that performanc...

  13. Communication received from the United Kingdom of Great Britain and Northern Ireland

    International Nuclear Information System (INIS)

    1998-01-01

    The document reproduces the text of a letter received by the Director General of the IAEA on 11 September 1998 from the Governor of the United Kingdom concerning the policy of the UK Government related to fissile material transparency, safeguards and irreversibility initiatives

  14. Ecological importance of intermediate windstorms rivals large, infrequent disturbances in the northern Great Lakes

    Science.gov (United States)

    Kirk M. Stueve; Charles H. (Hobie) Perry; Mark D. Nelson; Sean P. Healey; Andrew D. Hill; Gretchen G. Moisen; Warren B. Cohen; Dale D. Gormanson; Chengquan. Huang

    2011-01-01

    Exogenous disturbances are critical agents of change in temperate forests capable of damaging trees and influencing forest structure, composition, demography, and ecosystem processes. Forest disturbances of intermediate magnitude and intensity receive relatively sparse attention, particularly at landscape scales, despite influencing most forests at least once per...

  15. Plastic-Film Mulching for Enhanced Water-Use Efficiency and Economic Returns from Maize Fields in Semiarid China

    OpenAIRE

    Zhang, Peng; Wei, Ting; Cai, Tie; Ali, Shahzad; Han, Qingfang; Ren, Xiaolong; Jia, Zhikuan

    2017-01-01

    Film mulch has gradually been popularized to increase water availability to crops for improving and stabilizing agricultural production in the semiarid areas of Northwest China. To find more sustainable and economic film mulch methods for alleviating drought stress in semiarid region, it is necessary to test optimum planting methods in same cultivation conditions. A field experiment was conducted during 2013 and 2014 to evaluate the effects of different plastic film mulch methods on soil wate...

  16. Insert Maranhao in O cial Semi-Arid Geography: A Requirement of Social Justice in the Brazilian Northeast

    Directory of Open Access Journals (Sweden)

    José de Jesus Sousa Lemos

    2016-07-01

    Full Text Available The study attempts to show that the Brazilian semi-arid region is a region too needy. Even the Interior Ministry considering that there are municipalities only in the semiarid in eight of the Northeastern States excluding Maranhão, but incorporating municipalities in the state of Minas Gerais, the study also seeks to show that at least fteen municipalities of Maranhão has semiarid features and these municipalities have some of the largest pockets of poverty in this Brazilian ecosystem. In order to achieve its objectives the study uses data collected by the State University of Maranhão, the Demographic Census of IBGE 2010 and the GDP of the municipalities published by the IBGE in 2012. They use the estimated drought indices in a previous study of the State University of Maranhão to the Maranhão municipalities supposed to possess technical characteristics of semiarid region. Social indicators are estimated suchas education exclusion, income, running water, sanitation and garbage collection to all municipalities. The results showed that the average GDP of the semi-arid districts are much smaller than that of other municipalities in the Northeast. The ratio between the highest and the lowest GDP per capita in the semiarid region is 38.4. The iliteracy rates are high in all of them. Very high is also deprivation of access to piped water, sanitation and garbage collection also. e evidence of this study allow us to conclude that, in general, municipalities with technical characteristics of semi-arid in Maranhao State has economic, social and environmental indicators worse than the average of other municipalities already recognized in the Brazilian semiarid region.

  17. Great earthquakes along the Western United States continental margin: implications for hazards, stratigraphy and turbidite lithology

    Science.gov (United States)

    Nelson, C. H.; Gutiérrez Pastor, J.; Goldfinger, C.; Escutia, C.

    2012-11-01

    We summarize the importance of great earthquakes (Mw ≳ 8) for hazards, stratigraphy of basin floors, and turbidite lithology along the active tectonic continental margins of the Cascadia subduction zone and the northern San Andreas Transform Fault by utilizing studies of swath bathymetry visual core descriptions, grain size analysis, X-ray radiographs and physical properties. Recurrence times of Holocene turbidites as proxies for earthquakes on the Cascadia and northern California margins are analyzed using two methods: (1) radiometric dating (14C method), and (2) relative dating, using hemipelagic sediment thickness and sedimentation rates (H method). The H method provides (1) the best estimate of minimum recurrence times, which are the most important for seismic hazards risk analysis, and (2) the most complete dataset of recurrence times, which shows a normal distribution pattern for paleoseismic turbidite frequencies. We observe that, on these tectonically active continental margins, during the sea-level highstand of Holocene time, triggering of turbidity currents is controlled dominantly by earthquakes, and paleoseismic turbidites have an average recurrence time of ~550 yr in northern Cascadia Basin and ~200 yr along northern California margin. The minimum recurrence times for great earthquakes are approximately 300 yr for the Cascadia subduction zone and 130 yr for the northern San Andreas Fault, which indicates both fault systems are in (Cascadia) or very close (San Andreas) to the early window for another great earthquake. On active tectonic margins with great earthquakes, the volumes of mass transport deposits (MTDs) are limited on basin floors along the margins. The maximum run-out distances of MTD sheets across abyssal-basin floors along active margins are an order of magnitude less (~100 km) than on passive margins (~1000 km). The great earthquakes along the Cascadia and northern California margins cause seismic strengthening of the sediment, which

  18. Great earthquakes along the Western United States continental margin: implications for hazards, stratigraphy and turbidite lithology

    Directory of Open Access Journals (Sweden)

    C. H. Nelson

    2012-11-01

    Full Text Available We summarize the importance of great earthquakes (Mw ≳ 8 for hazards, stratigraphy of basin floors, and turbidite lithology along the active tectonic continental margins of the Cascadia subduction zone and the northern San Andreas Transform Fault by utilizing studies of swath bathymetry visual core descriptions, grain size analysis, X-ray radiographs and physical properties. Recurrence times of Holocene turbidites as proxies for earthquakes on the Cascadia and northern California margins are analyzed using two methods: (1 radiometric dating (14C method, and (2 relative dating, using hemipelagic sediment thickness and sedimentation rates (H method. The H method provides (1 the best estimate of minimum recurrence times, which are the most important for seismic hazards risk analysis, and (2 the most complete dataset of recurrence times, which shows a normal distribution pattern for paleoseismic turbidite frequencies. We observe that, on these tectonically active continental margins, during the sea-level highstand of Holocene time, triggering of turbidity currents is controlled dominantly by earthquakes, and paleoseismic turbidites have an average recurrence time of ~550 yr in northern Cascadia Basin and ~200 yr along northern California margin. The minimum recurrence times for great earthquakes are approximately 300 yr for the Cascadia subduction zone and 130 yr for the northern San Andreas Fault, which indicates both fault systems are in (Cascadia or very close (San Andreas to the early window for another great earthquake.

    On active tectonic margins with great earthquakes, the volumes of mass transport deposits (MTDs are limited on basin floors along the margins. The maximum run-out distances of MTD sheets across abyssal-basin floors along active margins are an order of magnitude less (~100 km than on passive margins (~1000 km. The great earthquakes along the Cascadia and northern California margins

  19. Exploring Niches for Short-Season Grain Legumes in Semi-Arid Eastern Kenya — Coping with the Impacts of Climate Variability

    Directory of Open Access Journals (Sweden)

    Anne Sennhenn

    2017-05-01

    Full Text Available Climate variability is the major risk to agricultural production in semi-arid agroecosystems and the key challenge to sustain farm livelihoods for the 500 million people who inhabit these areas worldwide. Short-season grain legumes have great potential to address this challenge and help to design more resilient and productive farming systems. However, grain legumes display a great diversity and differ widely in growth, development, and resource use efficiency. Three contrasting short season grain legumes common bean (Phaseolus vulgaris L., cowpea (Vigna unguiculata (L. Walp.] and lablab [Lablab purpureus (L. Sweet] were selected to assess their agricultural potential with respect to climate variability and change along the Machakos-Makueni transect in semi-arid Eastern Kenya. This was undertaken using measured data [a water response trial conducted during 2012/13 and 2013/14 in Machakos, Kenya] and simulated data using the Agricultural Production System sIMulator (APSIM. The APSIM crop model was calibrated and validated to simulate growth and development of short-season grain legumes in semi-arid environments. Water use efficiency (WUE was used as indicator to quantify the production potential. The major traits of adaptation include early flowering and pod and seed set before the onset of terminal drought. Early phenology together with adapted canopy architecture allowed more optimal water use and greater partitioning of dry matter into seed (higher harvest index. While common bean followed a comparatively conservative strategy of minimizing water loss through crop transpiration, the very short development time and compact growth habit limited grain yield to rarely exceed 1,000 kg ha−1. An advantage of this strategy was relatively stable yields independent of in-crop rainfall or season length across the Machakos-Makueni transect. The growth habit of cowpea in contrast minimized water loss through soil evaporation with rapid ground cover and

  20. Exploring Niches for Short-Season Grain Legumes in Semi-Arid Eastern Kenya - Coping with the Impacts of Climate Variability.

    Science.gov (United States)

    Sennhenn, Anne; Njarui, Donald M G; Maass, Brigitte L; Whitbread, Anthony M

    2017-01-01

    Climate variability is the major risk to agricultural production in semi-arid agroecosystems and the key challenge to sustain farm livelihoods for the 500 million people who inhabit these areas worldwide. Short-season grain legumes have great potential to address this challenge and help to design more resilient and productive farming systems. However, grain legumes display a great diversity and differ widely in growth, development, and resource use efficiency. Three contrasting short season grain legumes common bean ( Phaseolus vulgaris L.), cowpea ( Vigna unguiculata (L.) Walp.] and lablab [ Lablab purpureus (L.) Sweet] were selected to assess their agricultural potential with respect to climate variability and change along the Machakos-Makueni transect in semi-arid Eastern Kenya. This was undertaken using measured data [a water response trial conducted during 2012/13 and 2013/14 in Machakos, Kenya] and simulated data using the Agricultural Production System sIMulator (APSIM). The APSIM crop model was calibrated and validated to simulate growth and development of short-season grain legumes in semi-arid environments. Water use efficiency (WUE) was used as indicator to quantify the production potential. The major traits of adaptation include early flowering and pod and seed set before the onset of terminal drought. Early phenology together with adapted canopy architecture allowed more optimal water use and greater partitioning of dry matter into seed (higher harvest index). While common bean followed a comparatively conservative strategy of minimizing water loss through crop transpiration, the very short development time and compact growth habit limited grain yield to rarely exceed 1,000 kg ha -1 . An advantage of this strategy was relatively stable yields independent of in-crop rainfall or season length across the Machakos-Makueni transect. The growth habit of cowpea in contrast minimized water loss through soil evaporation with rapid ground cover and dry matter

  1. Exploring Niches for Short-Season Grain Legumes in Semi-Arid Eastern Kenya — Coping with the Impacts of Climate Variability

    Science.gov (United States)

    Sennhenn, Anne; Njarui, Donald M. G.; Maass, Brigitte L.; Whitbread, Anthony M.

    2017-01-01

    Climate variability is the major risk to agricultural production in semi-arid agroecosystems and the key challenge to sustain farm livelihoods for the 500 million people who inhabit these areas worldwide. Short-season grain legumes have great potential to address this challenge and help to design more resilient and productive farming systems. However, grain legumes display a great diversity and differ widely in growth, development, and resource use efficiency. Three contrasting short season grain legumes common bean (Phaseolus vulgaris L.), cowpea (Vigna unguiculata (L.) Walp.] and lablab [Lablab purpureus (L.) Sweet] were selected to assess their agricultural potential with respect to climate variability and change along the Machakos-Makueni transect in semi-arid Eastern Kenya. This was undertaken using measured data [a water response trial conducted during 2012/13 and 2013/14 in Machakos, Kenya] and simulated data using the Agricultural Production System sIMulator (APSIM). The APSIM crop model was calibrated and validated to simulate growth and development of short-season grain legumes in semi-arid environments. Water use efficiency (WUE) was used as indicator to quantify the production potential. The major traits of adaptation include early flowering and pod and seed set before the onset of terminal drought. Early phenology together with adapted canopy architecture allowed more optimal water use and greater partitioning of dry matter into seed (higher harvest index). While common bean followed a comparatively conservative strategy of minimizing water loss through crop transpiration, the very short development time and compact growth habit limited grain yield to rarely exceed 1,000 kg ha−1. An advantage of this strategy was relatively stable yields independent of in-crop rainfall or season length across the Machakos-Makueni transect. The growth habit of cowpea in contrast minimized water loss through soil evaporation with rapid ground cover and dry matter

  2. Sanctuaries for lake trout in the Great Lakes

    Science.gov (United States)

    Stanley, Jon G.; Eshenroder, Randy L.; Hartman, Wilbur L.

    1987-01-01

    Populations of lake trout, severely depleted in Lake Superior and virtually extirpated from the other Great Lakes because of sea lamprey predation and intense fishing, are now maintained by annual plantings of hatchery-reared fish in Lakes Michigan, Huron, and Ontario and parts of Lake Superior. The extensive coastal areas of the Great Lakes and proximity to large populations resulted in fishing pressure on planted lake trout heavy enough to push annual mortality associated with sport and commercial fisheries well above the critical level needed to reestablish self-sustaining stocks. The interagency, international program for rehabilitating lake trout includes controlling sea lamprey abundance, stocking hatchery-reared lake trout, managing the catch, and establishing sanctuaries where harvest is prohibited. Three lake trout sanctuaries have been established in Lake Michigan: the Fox Island Sanctuary of 121, 500 ha, in the Chippewa-Ottawa Treaty fishing zone in the northern region of the lake; the Milwaukee Reef Sanctuary of 160, 000 ha in midlake, in boundary waters of Michigan and Wisconsin; and Julian's Reef Sanctuary of 6, 500 ha, in Illinois waters. In northern Lake Huron, Drummond Island Sanctuary of 55, 000 ha is two thirds in Indian treaty-ceded waters in Michigan and one third in Ontario waters of Canada. A second sanctuary, Six Fathom Bank-Yankee Reef Sanctuary, in central Lake Huron contains 168, 000 ha. Sanctuary status for the Canadian areas remains to be approved by the Provincial government. In Lake Superior, sanctuaries protect the spawning grounds of Gull Island Shoal (70, 000 ha) and Devils Island Shoal (44, 000 ha) in Wisconsin's Apostle Island area. These seven sanctuaries, established by the several States and agreed upon by the States, Indian tribes, the U.S. Department of the Interior, and the Province of Ontario, contribute toward solving an interjurisdictional fishery problem.

  3. Northern Eurasia Future Initiative (NEFI)

    DEFF Research Database (Denmark)

    Groisman, Pavel; Shugart, Herman; Kicklighter, David

    2017-01-01

    . The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to better...

  4. Seedling survival of Handroanthus impetiginosus (Mart ex DC Mattos in a semi-arid environment through modified germination speed and post-germination desiccation tolerance

    Directory of Open Access Journals (Sweden)

    J. R. Martins

    Full Text Available Abstract Uniform rapid seed germination generally forms a great risk for the plant population if subsequent intermittent precipitation causes desiccation and seedling death. Handroanthus impetiginosus can be found commonly in a wide range of biomes within Brazil including those that are semi-arid. Germination and early growth was studied to understand how germinated seeds survive under these stringent conditions. Accessions were sampled from four seasonally dry biomes in Brazil. Precipitation at the start of the rainy season in the Caatinga, a semi-arid biome, is less predictable and the number of successive dry days per dry interval in the first four months of the rainy season was higher than in the other studied biomes. Plants from the Caatinga produced thicker seeds and this trait concurred with slow germination and stronger osmotic inhibition of germination across the accessions, forming a stress avoidance mechanism in the Caatinga. Post-germination desiccation tolerance was high in the Caatinga accession, could be re-induced in accessions from biomes with more regular precipitation (Cerrado and transition zone, but remained poor in the Cerradão accession; thus forming a stress tolerance mechanism. Production of adventitious roots ascertained survival of all tested individuals from all four locations, even if protruded radicles did not survive desiccation, forming an additional stress tolerance mechanism. A sequence of stress avoidance and stress tolerance mechanisms in seeds and germinated seeds was associated with precipitation patterns in different biomes. These mechanisms purportedly allow rapid seedling establishment when conditions are suitable and enable survival of the young seedling when conditions are adverse.

  5. Socio-economic effect on socially-deprived communities of developing drinking water quality problems in arid and semi-arid area of central Rajasthan

    Directory of Open Access Journals (Sweden)

    I. Husain

    2014-09-01

    Full Text Available Rajasthan is well known for its Great Thar desert. Central Rajasthan has an arid to semi-arid environment. The area faces either scarcity of water or poor quality of drinking water. In some areas water is transported 2 km or more, which uses time, energy and money. Rich people have their own sources, which is restricted for use by others. Such conditions are affecting socially-deprived communities, both socially and economically. Groundwater is a major source of drinking water due to the unavailability of surface water. There is a lack of groundwater quality knowledge in the community and the data available is hard to understand by consumers. The CCME Water Quality Index is a tool to simplify the water quality report by rating the water on quality standards. It provides meaningful summaries of overall water quality and trends, which is accessible to non-technical lay people. In the present study the objective is to examine the groundwater quality of six districts (Ajmer, Bhilwara, Pali, Rajasamand, Nagaur and Jodhpur, centrally located in Rajasthan, with arid and semi-arid conditions. CCME WQI is also evaluated to produce quality data in a form to be understood by the community. A total of 4369 groundwater sources in 1680 villages from six districts (76 546 km2 were collected and examined. Results are outlined in the Bureau of Indian Standards (BIS: 10500, 2012 and 2952 sources are unsafe for drinking. According to CCME WQI groundwater of 93 villages is poor, 343 villages are marginal, and 369 villages are fair in quality. Toxicological studies of unsafe drinking water and their remedial measures are also discussed. A tentative correlation between prevailing water-borne diseases and quality parameter has also been shown

  6. Soil water effect on crop growth, leaf gas exchange, water and radiation use efficiency of Saccharum spontaneum L. ssp. aegyptiacum (Willd. Hackel in semi-arid Mediterranean environment

    Directory of Open Access Journals (Sweden)

    Danilo Scordia

    2015-12-01

    Full Text Available Great effort has been placed to identify the most suited bioenergy crop under different environments and management practices, however, there is still need to find new genetic resources for constrained areas. For instance, South Mediterranean area is strongly affected by prolonged drought, high vapour pressure deficit (VPD and extremely high temperatures during summertime. In the present work we investigated the soil water effect on crop growth and leaf gas exchange of Saccharum spontaneum L. ssp. aegyptiacum (Willd. Hackel, a perennial, rhizomatous, herbaceous grass. Furthermore, the net increase of biomass production per unit light intercepted [radiation use efficiency (RUE] and per unit water transpired [water use efficiency (WUE] was also studied. To this end a field trial was carried out imposing three levels of soil water availability (I100, I50 and I0, corresponding to 100%, 50% and 0% of ETm restutition under a semi-arid Mediterranean environment. Leaf area index (LAI, stem height, biomass dry matter yield, CO2 assimilation rate, and transpiration rate resulted significantly affected by measurement time and irrigation treatment, with the highest values in I100 and the lowest in I0. RUE was the highest in I100 followed by I50 and I0; on the other hand, WUE was higher in I0 than I50 and I100. At LAI values greater than 2.0, 85% photosynthetically active radiation was intercepted by the Saccharum stand, irrespective of the irrigation treatment. Saccharum spontaneum spp. aegyptiacum is a potential species for biomass production in environment characterized by drought stress, high temperatures and high VPD, as those of Southern Europe and similar semi-arid areas.

  7. ESTIMATION OF EXTRACELLULAR LIPOLYTIC ENZYME ACTIVITY BY THERMOPHILIC BACILLUS SP. ISOLATED FROM ARID AND SEMI-ARID REGION OF RAJASTHAN, INDIA

    Directory of Open Access Journals (Sweden)

    Deeksha Gaur

    2012-10-01

    Full Text Available Thermophilic organisms can be defined as, micro-organisms which are adapted to survive at high temperatures. The enzymes secreted by thermophilic bacteria are capable of catalyzing biochemical reactions at high temperatures. Thermophilic bacteria are able to produce thermostable lipolytic enzymes (capable of degradation of lipid at temperatures higher than mesophilic bacteria. Therefore, the isolation of thermophilic bacteria from natural sources and their identification are quite beneficial in terms of discovering thermostable lipase enzymes. Due to great temperature fluctuation in hot arid and semi-arid region of Rajasthan, this area could serve as a good source for new thermophilic lipase producing bacteria with novel industrially important properties. The main objective of this research is the isolation and estimation of industrially important thermophilic lipase enzyme produced by thermophilic bacteria, isolated from arid and semi-arid region of Rajasthan. For this research purpose soil samples were collected from Churu, Sikar and Jhunjunu regions of Rajasthan. Total 16 bacterial strains were isolated and among only 2 thermostable lipolytic enzyme producing bacteria were charcterized. The thermostable lipolytic enzyme was estimated by qualitative and quantitative experiments. The isolates were identified as Bacillus sp. by microscopic, biochemical and molecular characterization. The optimum enzyme activity was observed at pH 8, temperature 60°C and 6% salt concentrations at 24 hrs time duration. Lipolytic enzyme find useful in a variety of biotechnological fields such as food and dairy (cheese ripening, flavour development, detergent, pharmaceutical (naproxen, ibuprofen, agrochemical (insecticide, pesticide and oleochemical (fat and oil hydrolysis, biosurfactant synthesis industries. Lipolytic enzyme can be further used in many newer areas where they can serve as potential biocatalysts.

  8. Monitoring the variations of evapotranspiration due to land use/cover change in a semiarid shrubland

    Science.gov (United States)

    Gong, Tingting; Lei, Huimin; Yang, Dawen; Jiao, Yang; Yang, Hanbo

    2017-02-01

    Evapotranspiration (ET) is an important process in the hydrological cycle, and vegetation change is a primary factor that affects ET. In this study, we analyzed the annual and inter-annual characteristics of ET using continuous observation data from eddy covariance (EC) measurement over 4 years (1 July 2011 to 30 June 2015) in a semiarid shrubland of Mu Us Sandy Land, China. The Normalized Difference Vegetation Index (NDVI) was demonstrated as the predominant factor that influences the seasonal variations in ET. Additionally, during the land degradation and vegetation rehabilitation processes, ET and normalized ET both increased due to the integrated effects of the changes in vegetation type, topography, and soil surface characteristics. This study could improve our understanding of the effects of land use/cover change on ET in the fragile ecosystem of semiarid regions and provide a scientific reference for the sustainable management of regional land and water resources.

  9. Produced water irrigation changes the soil mesofauna community in a semiarid agroecosystem.

    Science.gov (United States)

    Ferreira, Raimundo Nonato Costa; Weber, Olmar Baller; Crisóstomo, Lindbergue Araujo

    2015-08-01

    The scarcity of water in semiarid regions requires alternative sources for irrigation to improve agricultural production. Here, we aimed to evaluate the effects of produced water from oil exploration on the structure of soil mesofauna during the dry and rainy seasons in irrigated sunflower and castor bean fields in a Brazilian semiarid region. Three irrigation treatments were applied on plots cultivated with castor beans and sunflowers: produced water treated by filtration (filtrated) or treated by reverse osmosis (reverse osmosis) and groundwater. The mesofauna under the biofuel crops was collected and identified during the dry and rainy seasons. Although the abundance and richness of the total fauna did not differ between seasons in sunflower plots, the community was altered. In castor beans, the abundance, richness, and community of mesofauna observed in plots irrigated with produced water differed from the groundwater treatment. Irrigation with produced water promotes important changes in soil fauna community that justify their assessment for the maintenance and monitoring of agroecosystems.

  10. Isotope and radiation techniques for efficient water and fertilizer use in semi-arid regions

    International Nuclear Information System (INIS)

    1986-04-01

    The Joint FAO/IAEA Division carried out a coordinated research programme, which was concerned with the efficiency of water and fertilizer uses in semi-arid farming systems. The present publication is a summary of the individual contributions from Belgium, Chile, Ivory Coast, Cyprus, France, India, Israel, Romania, Senegal, Sri Lanka and the United States of America, over the period 1978-1984. Water and fertilizer uptake by crops are dynamic processes affected by several factors of the soil-plant-atmosphere system. The neutron moisture meters were used not only to measure soil water contents but also to understand water dynamics under field conditions. Nitrogen is the most limiting nutrient in many semi-arid regions, and as its absorption is very much related to water dynamics in the soil, experiments using N-15 labelled fertilizer were carried out, which are presented in this report

  11. Arbuscular mycorrhizal fungi in a semi-arid, limestone mining-impacted area of Brazil

    Directory of Open Access Journals (Sweden)

    Thaís Teixeira-Rios

    2013-12-01

    Full Text Available The main goal of this study was to determine the diversity and activity of arbuscular mycorrhizal fungi (AMF in an area degraded by limestone mining within the semi-arid region of Brazil known as the caatinga (shrublands. Near a limestone quarry, we selected two areas of caatinga (preserved and degraded for study. The number of glomerospores did not differ significantly between the two areas. There was a trend toward the most probable number of infective propagules being higher in the degraded area. Twenty AMF taxa were identified in the two sampled areas, species richness, diversity and evenness being higher in the preserved area. Two species of Racocetra represent new records for the semi-arid region of Brazil. Glomerospore production and AMF species richness were unaffected by mining activity in the study area.

  12. Transfer of 137Cs in Zea mays and Phaseolus vulgaris in a semi-arid ecosystem

    International Nuclear Information System (INIS)

    Cervantes, M.L.; Segovia, N.; Gaso P, M.I.; Palacios, J.C.

    1999-01-01

    With the objective to analyse the transference of 137 Cs from soil to plants, it is realized a study in maize and bean plants in the Radioactive Waste Storage Center (CADER). This site is located in a semi-arid region with a characteristic vegetation of a sub humid temperature zone. So those plants maize and beans were cultivated in four zones near CADER during a four years period. The obtained results for 1991 to 1994 for 137 Cs in soil samples for those zones showed an evident contamination in zone 1, due to a rupture of an industrial source. In 1994 the effect of decontamination was evident since the values of specific activity found in roots were around magnitude lesser than found in 1992. In spite of exhaustive studies have been reported about the transference factors for 137 Cs in different agricultural foods, relatively few of them have paid attention to the interactions between cereals and leguminous associated in semiarid ecosystems. (Author)

  13. Water balance of two earthen landfill caps in a semi-arid climate

    International Nuclear Information System (INIS)

    Khire, M.V.; Benson, C.H.; Bosscher, P.J.

    1997-01-01

    Water balance data are presented that were obtained from two earthen cap test sections located in a semi-arid region. The test sections were constructed on a municipal solid waste landfill in East Wenatchee, Washington, USA. One test section represents a traditional resistive barrier, and is constructed with a compacted silty clay barrier 60 cm thick and a vegetated silty clay surface layer 15 cm thick. The other test section represents a capillary barrier and has a sand layer 75 cm thick overlain by a 15-cm-thick vegetated surface layer of silt. Extensive hydrological and meteorological data have been collected since November 1992. Unsaturated hydraulic properties of soils, hydrologic parameters, and vegetation have been extensively characterized. Results of the study show that capillary barriers can be effective caps in semi-arid and arid regions. They are also cheaper to construct and can perform better than traditional resistive barriers

  14. Adaptation to the degradation of natural resources in the semiarid area of Mexico

    Directory of Open Access Journals (Sweden)

    José Luis Gonzalez Barrios

    2010-12-01

    Full Text Available Hydrology and soil research in the semiarid zone of Mexico highlight an erosion process that is worsened by climate and land use changes. Scientific results have inspired a successful adaptation program with an environmental and socioeconomic scope. The Hydrological Environmental Services Programm.e (PSAH, in Spanish pays local workers to build soil and water conservation infrastructure in areas with the potential to provide hydrological environmental services. The programme’s results are still under assessment, but some qualitative results may be already identified: soil and water retention, plant cover recovery, permanence of local people in their comm.unities, and social welfare, among others. The PSAH as a strategy should be echoed in other places of Mexico in order to replicate their benefits on the physical and human environments of the semiarid zone.

  15. Will water scarcity in semiarid regions limit hydraulic fracturing of shale plays?

    International Nuclear Information System (INIS)

    Scanlon, Bridget R; Reedy, Robert C; Philippe Nicot, Jean

    2014-01-01

    There is increasing concern about water constraints limiting oil and gas production using hydraulic fracturing (HF) in shale plays, particularly in semiarid regions and during droughts. Here we evaluate HF vulnerability by comparing HF water demand with supply in the semiarid Texas Eagle Ford play, the largest shale oil producer globally. Current HF water demand (18 billion gallons, bgal; 68 billion liters, bL in 2013) equates to ∼16% of total water consumption in the play area. Projected HF water demand of ∼330 bgal with ∼62 000 additional wells over the next 20 years equates to ∼10% of historic groundwater depletion from regional irrigation. Estimated potential freshwater supplies include ∼1000 bgal over 20 yr from recharge and ∼10 000 bgal from aquifer storage, with land-owner lease agreements often stipulating purchase of freshwater. However, pumpage has resulted in excessive drawdown locally with estimated declines of ∼100–200 ft in ∼6% of the western play area since HF began in 2009–2013. Non-freshwater sources include initial flowback water, which is ≤5% of HF water demand, limiting reuse/recycling. Operators report shifting to brackish groundwater with estimated groundwater storage of 80 000 bgal. Comparison with other semiarid plays indicates increasing brackish groundwater and produced water use in the Permian Basin and large surface water inputs from the Missouri River in the Bakken play. The variety of water sources in semiarid regions, with projected HF water demand representing ∼3% of fresh and ∼1% of brackish water storage in the Eagle Ford footprint indicates that, with appropriate management, water availability should not physically limit future shale energy production. (letter)

  16. Germination patterns of a suite of semiarid grassland forbs from central New Mexico

    Science.gov (United States)

    Rosemary L. Pendleton; Burton K. Pendleton

    2014-01-01

    We examined the germination response of 21 forb species collected from semiarid grasslands of central New Mexico. After-ripened seeds were subjected to 1 of 3 treatments: 1) no treatment; 2) a 3-wk stratification at 5 °C (cold-moist treatment); or 3) a 3-wk warm-moist treatment at 30 °C. All seeds were incubated under an alternating 10/20 °C temperature regime for 6 wk...

  17. Economic evaluation of cereal cropping systems under semiarid conditions: minimum input, organic and conventional

    OpenAIRE

    Pardo,Gabriel; Aibar,Joaquín; Cavero,José; Zaragoza,Carlos

    2009-01-01

    Cropping systems like organic farming, selling products at a higher price and promoting environmental sustainability by reducing fertilizer and pesticides, can be more profitable than conventional systems. An economic evaluation of three cropping systems in a seven year period experiment was performed, using a common rotation (fallow-barley-vetch-durum wheat) in a semi-arid rainfed field of Spain. The minimum input system included mouldboard ploughing, cultivator preparation, sowing and harve...

  18. Soil quality improvement for crop production in semi-arid West Africa

    OpenAIRE

    Ouédraogo, E.

    2004-01-01

    Soil quality maintenance and crop production improvement in semi-arid West Africa require appropriate cropping technologies, which are ecologically sound and economically viable. Thus, on-farm and on-station experiments have been carried out on the central plateau and in the south of Burkina Faso The results show that adoption of improved soil fertility technologies such as composting by farmers is determined by soil fertility status, access to the market and social reasons. Organic amendment...

  19. Agroforestry parkland species diversity : uses and management in semi-arid West-Africa (Burkina Faso)

    OpenAIRE

    Nikiema, A.

    2005-01-01

    Agroforestry parkland in semi-arid West Africa is a rural land use system, which allows farmers to grow annual crops in combination with useful trees. In addition to cereals, tree products such as vegetables, fruits, vegetable oil, firewood, fodder, and medicines are obtained from the parklands. However the multiple function of the parkland system can only be fulfilled if parkland species diversity is adequately managed.This thesis is focused on assessing the woody species diversity in the pa...

  20. Changes in zinc speciation with mine tailings acidification in a semi-arid weathering environment

    OpenAIRE

    Hayes, Sarah M.; O’Day, Peggy A.; Webb, Sam M.; Maier, Raina M.; Chorover, Jon

    2011-01-01

    High concentrations of residual metal contaminants in mine tailings can be transported easily by wind and water, particularly when tailings remain unvegetated for decades following mining cessation, as is the case in semi-arid landscapes. Understanding the speciation and mobility of contaminant metal(loid)s, particularly in surficial tailings, is essential to controlling their phytotoxicities and to revegetating impacted sites. In prior work, we showed that surficial tailings samples from the...

  1. Insolation driven biomagnetic response to the Holocene Warm Period in semi-arid East Asia

    OpenAIRE

    Liu, Suzhen; Deng, Chenglong; Xiao, Jule; Li, Jinhua; Paterson, Greig A.; Chang, Liao; Yi, Liang; Qin, Huafeng; Pan, Yongxin; Zhu, Rixiang

    2015-01-01

    The Holocene Warm Period (HWP) provides valuable insights into the climate system and biotic responses to environmental variability and thus serves as an excellent analogue for future global climate changes. Here we document, for the first time, that warm and wet HWP conditions were highly favourable for magnetofossil proliferation in the semi-arid Asian interior. The pronounced increase of magnetofossil concentrations at ~9.8?ka and decrease at ~5.9?ka in Dali Lake coincided respectively wit...

  2. Competing effects of groundwater withdrawals and climate change on water availability in semi-arid India

    Science.gov (United States)

    Sishodia, R. P.; Shukla, S.

    2017-12-01

    India, a global leader in groundwater use (250 km3/yr), is experiencing groundwater depletion. There has been a 130-fold increase in number of irrigation wells since 1960. Anticipated future increase in groundwater demand is likely to exacerbate the water availability in the semi-arid regions of India. Depending on the direction of change, future climate change may either worsen or enhance the water availability. This study uses an integrated hydrologic modeling approach (MIKE SHE MIKE 11) to compare and combine the effects of future (2040-2069) increased groundwater withdrawals and climate change on surface and groundwater flows and availability for an agricultural watershed in semi-arid south India. Modeling results showed that increased groundwater withdrawals in the future resulted in reduced surface flows (25%) and increased frequency and duration (90 days/yr) of well drying. In contrast, projected future increase in rainfall (7-43%) under the changed climate showed increased groundwater recharge (15-67%) and surface flows (9-155%). Modeling results suggest that the positive effects of climate change may enhance the water availability in this semi-arid region of India. However, in combination with increased withdrawals, climate change was shown to increase the well drying and reduce the water availability especially during dry years. A combination of management options such as flood to drip conversion, energy subsidy reductions and water storage can support increased groundwater irrigated area in the future while mitigating the well drying. A cost-benefit analysis showed that dispersed water storage and flood to drip conversion can be highly cost-effective in this semi-arid region. The study results suggest that the government and management policies need to be focused towards an integrated management of demand and supply to create a sustainable food-water-energy nexus in the region.

  3. Antibacterial, Antioxidant, and Anticholinesterase Activities of Plant Seed Extracts from Brazilian Semiarid Region

    OpenAIRE

    Davi Felipe Farias; Terezinha Maria Souza; Martônio Ponte Viana; Bruno Marques Soares; Arcelina Pacheco Cunha; Ilka Maria Vasconcelos; Nágila Maria Pontes Silva Ricardo; Paulo Michel Pinheiro Ferreira; Vânia Maria Maciel Melo; Ana Fontenele Urano Carvalho

    2013-01-01

    The antimicrobial, antioxidant, and anticholinesterase activities of ethanolic seed extracts of twenty-one plant species from Brazilian semiarid region were investigated. The extracts were tested for antimicrobial activity against six bacteria strains and three yeasts. Six extracts presented activity against the Gram (−) organism Salmonella choleraesuis and the Gram (+) organisms Staphylococcus aureus and Bacillus subtilis. The MIC values ranged from 4.96 to 37.32 mg/mL. The Triplaris gardner...

  4. Use of fertilizer nitrogen by wheat in semiarid region of the pampa, Argentina

    International Nuclear Information System (INIS)

    Lazzari, M.A.; Laurent, G.C.

    1984-01-01

    The efficiency of nitrogen utilization by wheat (Buck Pucara cultivar) in semiarid region of the Argentina Pampas is studied. A single-treatment-fertility-experimet is used, and in this method all treatments, as far as the plant, soil or environment are concerned, are identical. The only difference is the occurrence of the 15 N label within a given subtreatment. (M.A.C.) [pt

  5. Continental margin evolution of the northern Arabian platform in Syria

    Energy Technology Data Exchange (ETDEWEB)

    Best, J.A.; Barazangi, M. (Cornell Univ., Ithaca, NY (United States)); Al-Saad, D.; Sawaf, T.; Gebran, A. (Syrian Petroleum Company, Damascus (Syrian Arab Republic))

    1993-02-01

    Synthesis of available geological and geophysical data in the Syrian Arab Republic permits a descriptive account of the pre-Cenozoic geologic history of the northern Arabian platform. The northern Arabian platform appears to be a composite plate similar up to that interpreted in the rocks of the Arabian shield. The structural and stratigraphic relationships of the Paleozoic and Mesozoic sedimentary sections in Syria record the transformation of an eastward-facing Gondwana passive margin in the early Paleozoic into a westward-facing Levantine margin in the Mesozoic, at which time the northern platform was closely associated with the creation of the eastern Mediterranean basin. Timing of the margin transformation is inferred from the orientation and thickness variations of Lower Triassic rocks, but the transformation may have initiated as early as the Permian. The diversity and timing of geological features in Syria suggest that the northern Arabian platform did not behave as a rigid plate throughout its geological history. The present-day Palmyride mountain belt, located within the northern Arabian platform in Syria and initiated in the early Mesozoic as a northeast-trending rift nearly perpendicular to the Levantine margin, subsequently was inverted in the Cenozoic by transpression. The location of the rift may be associated with the reactivation of a zone of crustal weakness, i.e., a Proterozoic suture zone previously proposed from modeling of Bouguer gravity data. Thus, the northern and southern parts of the Arabian platform are similar in their respective geologic histories during the Proterozoic and Paleozoic; however, the northern Arabian platform was greatly affected by Mesozoic rifting and the creation of the eastern Mediterranean basin during the Mesozoic. 13 figs.

  6. Arbuscular mycorrhizal fungi in Mimosa tenuiflora (Willd. Poir from Brazilian semi-arid

    Directory of Open Access Journals (Sweden)

    Tancredo Augusto Feitosa de Souza

    2016-06-01

    Full Text Available Abstract Many plant species from Brazilian semi-arid present arbuscular mycorrhizal fungi (AMF in their rhizosphere. These microorganisms play a key role in the establishment, growth, survival of plants and protection against drought, pathogenic fungi and nematodes. This study presents a quantitative analysis of the AMF species associated with Mimosa tenuiflora, an important native plant of the Caatinga flora. AMF diversity, spore abundance and root colonization were estimated in seven sampling locations in the Ceará and Paraíba States, during September of 2012. There were significant differences in soil properties, spore abundance, percentage of root colonization, and AMF diversity among sites. Altogether, 18 AMF species were identified, and spores of the genera Acaulospora, Claroideoglomus, Dentiscutata, Entrophospora, Funneliformis, Gigaspora, Glomus, Racocetra, Rhizoglomus and Scutellospora were observed. AMF species diversity and their spore abundance found in M. tenuiflora rhizosphere shown that this native plant species is an important host plant to AMF communities from Brazilian semi-arid region. We concluded that: (a during the dry period and in semi-arid conditions, there is a high spore production in M. tenuiflora root zone; and (b soil properties, as soil pH and available phosphorous, affect AMF species diversity, thus constituting key factors for the similarity/dissimilarity of AMF communities in the M. tenuiflora root zone among sites.

  7. Phytostabilization of semiarid soils residually contaminated with trace elements using by-products: Sustainability and risks

    Energy Technology Data Exchange (ETDEWEB)

    Perez-de-Mora, Alfredo, E-mail: perezdemora@gmail.com [Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS), CSIC, PO Box 1052, 41080 Sevilla (Spain); Madejon, Paula; Burgos, Pilar; Cabrera, Francisco [Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS), CSIC, PO Box 1052, 41080 Sevilla (Spain); Lepp, Nicholas W. [35, Victoria Road, Formby, Liverpool L37 7DH (United Kingdom); Madejon, Engracia [Instituto de Recursos Naturales y Agrobiologia de Sevilla (IRNAS), CSIC, PO Box 1052, 41080 Sevilla (Spain)

    2011-10-15

    We investigated the efficiency of various by-products (sugarbeet lime, biosolid compost and leonardite), based on single or repeated applications to field plots, on the establishment of a vegetation cover compatible with a stabilization strategy on a multi-element (As, Cd, Cu, Pb and Zn) contaminated soil 4-6 years after initial amendment applications. Results indicate that the need for re-treatment is amendment- and element-dependent; in some cases, a single application may reduce trace element concentrations in above-ground biomass and enhance the establishment of a healthy vegetation cover. Amendment performance as evaluated by % cover, biomass and number of colonizing taxa differs; however, changes in plant community composition are not necessarily amendment-specific. Although the translocation of trace elements to the plant biotic compartment is greater in re-vegetated areas, overall loss of trace elements due to soil erosion and plant uptake is usually smaller compared to that in bare soil. - Highlights: > By-products enhance vegetation dynamics in contaminated semiarid soils. > Depending on the situation single or repeated incorporations may be required. > The structure of the plant community established is not amendment-dependent. > Phytostabilization reduces overall loss of trace elements in semiarid soils. - Phytostabilization using by-products as amendments is a suitable approach for long-term immobilization of various trace elements in semiarid contaminated soils.

  8. Phytostabilization of semiarid soils residually contaminated with trace elements using by-products: Sustainability and risks

    International Nuclear Information System (INIS)

    Perez-de-Mora, Alfredo; Madejon, Paula; Burgos, Pilar; Cabrera, Francisco; Lepp, Nicholas W.; Madejon, Engracia

    2011-01-01

    We investigated the efficiency of various by-products (sugarbeet lime, biosolid compost and leonardite), based on single or repeated applications to field plots, on the establishment of a vegetation cover compatible with a stabilization strategy on a multi-element (As, Cd, Cu, Pb and Zn) contaminated soil 4-6 years after initial amendment applications. Results indicate that the need for re-treatment is amendment- and element-dependent; in some cases, a single application may reduce trace element concentrations in above-ground biomass and enhance the establishment of a healthy vegetation cover. Amendment performance as evaluated by % cover, biomass and number of colonizing taxa differs; however, changes in plant community composition are not necessarily amendment-specific. Although the translocation of trace elements to the plant biotic compartment is greater in re-vegetated areas, overall loss of trace elements due to soil erosion and plant uptake is usually smaller compared to that in bare soil. - Highlights: → By-products enhance vegetation dynamics in contaminated semiarid soils. → Depending on the situation single or repeated incorporations may be required. → The structure of the plant community established is not amendment-dependent. → Phytostabilization reduces overall loss of trace elements in semiarid soils. - Phytostabilization using by-products as amendments is a suitable approach for long-term immobilization of various trace elements in semiarid contaminated soils.

  9. Arbuscular mycorrhizal fungi regulate soil respiration and its response to precipitation change in a semiarid steppe.

    Science.gov (United States)

    Zhang, Bingwei; Li, Shan; Chen, Shiping; Ren, Tingting; Yang, Zhiqiang; Zhao, Hanlin; Liang, Yu; Han, Xingguo

    2016-01-28

    Arbuscular mycorrhizal fungi (AMF) are critical links in plant-soil continuum and play a critical role in soil carbon cycles. Soil respiration, one of the largest carbon fluxes in global carbon cycle, is sensitive to precipitation change in semiarid ecosystems. In this study, a field experiment with fungicide application and water addition was conducted during 2010-2013 in a semiarid steppe in Inner Mongolia, China, and soil respiration was continuously measured to investigate the influences of AMF on soil respiration under different precipitation regimes. Results showed that soil respiration was promoted by water addition treatment especially during drought seasons, which induced a nonlinear response of soil respiration to precipitation change. Fungicide application suppressed AMF root colonization without impacts on soil microbes. AMF suppression treatment accelerated soil respiration with 2.7, 28.5 and 37.6 g C m(-2) across three seasons, which were mainly caused by the enhanced heterotrophic component. A steeper response of soil respiration rate to precipitation was found under fungicide application treatments, suggesting a greater dampening effect of AMF on soil carbon release as water availability increased. Our study highlighted the importance of AMF on soil carbon stabilization and sequestration in semiarid steppe ecosystems especially during wet seasons.

  10. Soil-atmosphere trace gas exchange in semiarid and arid zones.

    Science.gov (United States)

    Galbally, Ian E; Kirstine, Wayne V; Meyer, C P Mick; Wang, Ying Ping

    2008-01-01

    A review is presented on trace gas exchange of CH4, CO, N2O, and NOx arising from agriculture and natural sources in the world's semiarid and arid zones due to soil processes. These gases are important contributors to the radiative forcing and the chemistry of the atmosphere. Quantitative information is summarized from the available studies. Between 5 and 40% of the global soil-atmosphere exchange for these gases (CH4, CO, N2O, and NOx) may occur in semiarid and arid zones, but for each of these gases there are fewer than a dozen studies to support the individual estimates, and these are from a limited number of locations. Significant differences in the biophysical and chemical processes controlling these trace gas exchanges are identified through the comparison of semiarid and arid zones with the moist temperate or wet/dry savanna land regions. Therefore, there is a poorly quantified understanding of the contribution of these regions to the global trace gas cycles and atmospheric chemistry. More importantly, there is a poor understanding of the feedback between these exchanges, global change, and regional land use and air pollution issues. A set of research issues is presented.

  11. A zoological catalogue of hunted reptiles in the semiarid region of Brazil.

    Science.gov (United States)

    Nóbrega Alves, Rômulo Romeu; Pereira Filho, Gentil Alves; Silva Vieira, Kleber; Silva Souto, Wedson Medeiros; Mendonça, Lívia Emanuelle Tavares; Montenegro, Paulofernandoguedespereira; Almeida, Waltécio de Oliveira; Silva Vieira, Washington Luiz

    2012-07-30

    The variety of interactions between human cultures and herpetofauna is the subject matter of Ethnoherpetology, a subdivision of Ethnozoology. In the semi-arid region of Brazil, many reptiles interact with human communities because of their utility or because of the risks they represent. These interactions have obvious implications for the conservation of reptiles from this region. In this context, ethnoherpetology studies are crucial because they serve as subsidies for guiding strategies for the handling and conservation of reptiles. This paper presents ethnozoological and taxonomic informations of hunted reptiles in the semiarid region of Brazil and analyse the implications on conservation that are related to the interactions between people and reptiles in this region. Taxonomic keys to identifying recorded reptiles are provided. Records of humans interacting with 38 reptile species that belong to 31 genuses and 16 families have been found. The groups with the largest numbers of recorded species were snakes (18 species), and this group was followed in number by lizards (13), chelonians (4), and crocodilians (3). The reptiles that were recorded may be used for the following purposes: medicinal purposes (24 species), food (13 species), ornamental or decorative purposes (11 species), in magical/religious practices (10 species), and as pets (10 species). Some species (n = 16) may have multiple uses. Furthermore, more than half of the species (n = 19) are commonly killed because they are considered potentially dangerous. Strategies for conserving the reptiles of the Brazilian semi-arid region must reconcile and integrate human and conservation needs.

  12. Agroecological and Social Transformations for Coexistence with Semi-Aridity in Brazil

    Directory of Open Access Journals (Sweden)

    Aldrin M. Pérez-Marin

    2017-06-01

    Full Text Available This article explores whether a shift in development paradigm resulted in coexistence with semi-aridity for residents of the Semi-Arid region of Brazil (SAB. If so, which strategies contributed and which conditions facilitated it? We conducted a comparative analysis of the transformations that occurred in 10 territories of the SAB during two time periods: PI (1973–2001 when “development” policies almost exclusively aimed to “combat drought and its effects”; and PII (2002–2016 when a concept of coexistence with semi-aridity informed policy making. Our study from the 10 territories of the SAB show significant changes between PI and PII. On average, there was a substantial improvement in Access to Water Infrastructure (+33%∆, Diversification of Production Systems (Animals +36%∆; Crops +61%∆, Management of Common Pool Resources (+45%∆, Involvement in Spaces of Political Organizing (+24%∆, and Access to Public Programs (+29%∆. As such, “coexistence” went from concept to action as a consequence of structural, agroecological, social, and management transformations in combination with a strengthening of mechanisms for community reciprocity. These were characterized by (a the creation of resource reserves for use during times of drought; (b the efficient use of available natural resources; and (c enhanced articulation between diverse actors.

  13. Arbuscular mycorrhizal fungi regulate soil respiration and its response to precipitation change in a semiarid steppe

    Science.gov (United States)

    Zhang, Bingwei; Li, Shan; Chen, Shiping; Ren, Tingting; Yang, Zhiqiang; Zhao, Hanlin; Liang, Yu; Han, Xingguo

    2016-01-01

    Arbuscular mycorrhizal fungi (AMF) are critical links in plant-soil continuum and play a critical role in soil carbon cycles. Soil respiration, one of the largest carbon fluxes in global carbon cycle, is sensitive to precipitation change in semiarid ecosystems. In this study, a field experiment with fungicide application and water addition was conducted during 2010-2013 in a semiarid steppe in Inner Mongolia, China, and soil respiration was continuously measured to investigate the influences of AMF on soil respiration under different precipitation regimes. Results showed that soil respiration was promoted by water addition treatment especially during drought seasons, which induced a nonlinear response of soil respiration to precipitation change. Fungicide application suppressed AMF root colonization without impacts on soil microbes. AMF suppression treatment accelerated soil respiration with 2.7, 28.5 and 37.6 g C m-2 across three seasons, which were mainly caused by the enhanced heterotrophic component. A steeper response of soil respiration rate to precipitation was found under fungicide application treatments, suggesting a greater dampening effect of AMF on soil carbon release as water availability increased. Our study highlighted the importance of AMF on soil carbon stabilization and sequestration in semiarid steppe ecosystems especially during wet seasons.

  14. Coprophilous Mucorales (ex Zygomycota from three areas in the semi-arid of Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Fragoso de Souza

    Full Text Available Abstract Mucorales comprises fungi commonly isolated as saprobes from soil, dung, stored grains and plants. Although these fungi have been studied in several countries, there are relatively a few reports of them in semi-arid areas. Therefore, the aims of the present study were to assess and compare the Mucorales communities in dung from different species and breeds of herbivores in the semi-arid of Pernambuco, based on the frequency of occurrence and species richness of these fungi. Samples of dung collected in the cities of Arcoverde, Serra Talhada and Sertânia were incubated in moist chambers in triplicate. Altogether, 24 taxa of Mucorales distributed in the genera Absidia, Circinella, Cunninghamella, Lichtheimia, Mucor, Pilobolus, Rhizopus and Syncephalastrum were identified. The highest species richness was found in sheep excrement. Mucor circinelloides f. griseo-cyanus was the most common taxon, followed by M. ramosissimus. The similarity of the composition of Mucorales species was greatest between the excrements of Guzerá and Sindi breeds (bovine. All mucoralean species isolated are being cited for the first time from animal dung found in Caatinga and a new species of Mucor was recorded. An identification key for species of Mucorales from dung in the semi-arid region of Brazil is provided.

  15. Modeling water scarcity and droughts for policy adaptation to climate change in arid and semiarid regions

    Science.gov (United States)

    Kahil, Mohamed Taher; Dinar, Ariel; Albiac, Jose

    2015-03-01

    Growing water extractions combined with emerging demands for environment protection increase competition for scarce water resources worldwide, especially in arid and semiarid regions. In those regions, climate change is projected to exacerbate water scarcity and increase the recurrence and intensity of droughts. These circumstances call for methodologies that can support the design of sustainable water management. This paper presents a hydro-economic model that links a reduced form hydrological component, with economic and environmental components. The model is applied to an arid and semiarid basin in Southeastern Spain to analyze the effects of droughts and to assess alternative adaptation policies. Results indicate that drought events have large impacts on social welfare, with the main adjustments sustained by irrigation and the environment. The water market policy seems to be a suitable option to overcome the negative economic effects of droughts, although the environmental effects may weaken its advantages for society. The environmental water market policy, where water is acquired for the environment, is an appealing policy to reap the private benefits of markets while protecting ecosystems. The current water management approach in Spain, based on stakeholders' cooperation, achieves almost the same economic outcomes and better environmental outcomes compared to a pure water market. These findings call for a reconsideration of the current management in arid and semiarid basins around the world. The paper illustrates the potential of hydro-economic modeling for integrating the multiple dimensions of water resources, becoming a valuable tool in the advancement of sustainable water management policies.

  16. Coprophilous Mucorales (ex Zygomycota) from three areas in the semi-arid of Pernambuco, Brazil.

    Science.gov (United States)

    Souza, Carlos Alberto Fragoso de; Lima, Diogo Xavier; Gurgel, Luciana M S; Santiago, André Luiz Cabral Monteiro de Azevedo

    Mucorales comprises fungi commonly isolated as saprobes from soil, dung, stored grains and plants. Although these fungi have been studied in several countries, there are relatively a few reports of them in semi-arid areas. Therefore, the aims of the present study were to assess and compare the Mucorales communities in dung from different species and breeds of herbivores in the semi-arid of Pernambuco, based on the frequency of occurrence and species richness of these fungi. Samples of dung collected in the cities of Arcoverde, Serra Talhada and Sertânia were incubated in moist chambers in triplicate. Altogether, 24 taxa of Mucorales distributed in the genera Absidia, Circinella, Cunninghamella, Lichtheimia, Mucor, Pilobolus, Rhizopus and Syncephalastrum were identified. The highest species richness was found in sheep excrement. Mucor circinelloides f. griseo-cyanus was the most common taxon, followed by M. ramosissimus. The similarity of the composition of Mucorales species was greatest between the excrements of Guzerá and Sindi breeds (bovine). All mucoralean species isolated are being cited for the first time from animal dung found in Caatinga and a new species of Mucor was recorded. An identification key for species of Mucorales from dung in the semi-arid region of Brazil is provided. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  17. Effects of fishing technique on assessing species composition in aquatic systems in semi-arid Brazil

    Directory of Open Access Journals (Sweden)

    ESF Medeiros

    Full Text Available In most ecological field research, appropriate sampling is critical for the understanding of processes underlying fish populations and communities, and is even more important in heterogeneous environments such as the aquatic systems of the semi-arid region of Brazil. This study intends to make a contribution to the development of sampling programs and gear selection in aquatic systems of semi-arid Brazil by evaluating the effects of different fishing techniques on the assessment of richness and composition of the fish fauna in selected aquatic environments. Six sites were selected to represent typical artificial (reservoirs and natural (intermittent streams environments and four different types of sampling gear were applied to each site during four occasions. The present study shows that when selecting sampling techniques to be used in aquatic systems in semi-arid Brazil, one must consider the objectives of the study, e.g. ecological or taxonomic, in order to decide on inclusion of rare species in the sampling population. Also, the effect of the sampling gear on natural abundances of fish must be considered given that some sampling techniques are highly detrimental to fish population numbers.

  18. Effect of high ambient temperature on behavior of sheep under semi-arid tropical environment.

    Science.gov (United States)

    De, Kalyan; Kumar, Davendra; Saxena, Vijay Kumar; Thirumurugan, Palanisamy; Naqvi, Syed Mohammed Khursheed

    2017-07-01

    High environmental temperature is a major constraint in sheep production under semi-arid tropical environment. Behavior is the earliest indicator of animal's adaptation and responses to the environmental alteration. Therefore, the objective of this study was to assess the effects of high ambient temperature on the behavior of sheep under a semi-arid tropical environment. The experiment was conducted for 6 weeks on 16 Malpura cross (Garole × Malpura × Malpura (GMM)) rams. The rams were divided equally into two groups, designated as C and T. The rams of C were kept in comfortable environmental conditions served as control. The rams of T were exposed to a different temperature at different hours of the day in a climatic chamber, to simulate a high environmental temperature of summer in semi-arid tropic. The behavioral observations were taken by direct instantaneous observation at 15-min intervals for each animal individually. The feeding, ruminating, standing, and lying behaviors were recorded twice a week from morning (0800 hours) to afternoon (1700 hours) for 6 weeks. Exposure of rams to high temperature (T) significantly (P behavior of sheep which is directed to circumvent the effect of the stressor.

  19. Effect of high ambient temperature on behavior of sheep under semi-arid tropical environment

    Science.gov (United States)

    De, Kalyan; Kumar, Davendra; Saxena, Vijay Kumar; Thirumurugan, Palanisamy; Naqvi, Syed Mohammed Khursheed

    2017-07-01

    High environmental temperature is a major constraint in sheep production under semi-arid tropical environment. Behavior is the earliest indicator of animal's adaptation and responses to the environmental alteration. Therefore, the objective of this study was to assess the effects of high ambient temperature on the behavior of sheep under a semi-arid tropical environment. The experiment was conducted for 6 weeks on 16 Malpura cross (Garole × Malpura × Malpura (GMM)) rams. The rams were divided equally into two groups, designated as C and T. The rams of C were kept in comfortable environmental conditions served as control. The rams of T were exposed to a different temperature at different hours of the day in a climatic chamber, to simulate a high environmental temperature of summer in semi-arid tropic. The behavioral observations were taken by direct instantaneous observation at 15-min intervals for each animal individually. The feeding, ruminating, standing, and lying behaviors were recorded twice a week from morning (0800 hours) to afternoon (1700 hours) for 6 weeks. Exposure of rams to high temperature (T) significantly ( P animals of T spent significantly ( P behavior of sheep which is directed to circumvent the effect of the stressor.

  20. Use of GIS and Remote Sensing for Estimation of the Desertification of Northern Caspian Region

    Directory of Open Access Journals (Sweden)

    Shabanov Dmitriy Ivanovich

    2014-12-01

    Full Text Available Northern Caspian Region is a part of the territory of Russia. On the territory of the Northern Caspian Region arid and semi-arid landscapes exist and are used as pastures for ages. Mining, construction, installation and operation of communications, cultivation of land make significant impact to the environmental change of this territory. Desertification is the most typical respond to irrational environmental impact for the arid areas, and assessment of the current status and trends of desertification of the territory are necessary to determine the plans for the development and environment restoration missions. Four scenes from Landsat-8 (OLI, June 2014 have been processed via ENVI software. Top of the surface reflectance have been calculated, supervised and classified using ROI based on ground truth data. Based on the remote sensing data area of desertification was estimated and created a map “Desertification of the Northern Caspian Region.” The obtained data are preliminary and require further clarification, including verification by ground truth and further research.

  1. Effect of synthetic and natural water-absorbing soil amendments on photosynthesis characteristics and tuber nutritional quality of potato in a semi-arid region.

    Science.gov (United States)

    Xu, Shengtao; Zhang, Lei; McLaughlin, Neil B; Mi, Junzhen; Chen, Qin; Liu, Jinghui

    2016-02-01

    The effect of water-absorbing soil amendments on photosynthesis characteristics and tuber nutritional quality was investigated in a field experiment in a semi-arid region in northern China in 2010-2012. Treatments included two synthetic water-absorbing amendments, potassium polyacrylate (PAA) and polyacrylamide (PAM), and one natural amendment, humic acid (HA), both as single amendments and compound amendments (HA combined with PAA or PAM), and a no amendment control. Soil amendments had a highly significant effect (P ≤ 0.01) on photosynthesis characteristics, dry biomass, crop root/shoot (R/S) ratio and tuber nutritional quality. They improved both dry biomass above ground and dry biomass underground in the whole growing season by 4.6-31.2 and 1.1-83.1% respectively in all three years. Crop R/S ratio was reduced in the early growing season by 2.0-29.4% and increased in the later growing season by 2.3-32.6%. Soil amendments improved leaf soil plant analysis development value, net photosynthesis rate, stomatal conductance and transpiration rate by 1.4-17.0, 5.1-45.9, 2.4-90.6 and 2.0-22.6% respectively and reduced intercellular CO2 concentration by 2.1-19.5% in all three years. Amendment treatment with PAM + HA always had the greatest effect on photosynthesis characteristics and tuber nutritional quality among all amendment treatments and thus merits further research. © 2015 Society of Chemical Industry.

  2. Spatial Distribution of Aboveground Carbon Stock of the Arboreal Vegetation in Brazilian Biomes of Savanna, Atlantic Forest and Semi-Arid Woodland.

    Science.gov (United States)

    Scolforo, Henrique Ferraco; Scolforo, Jose Roberto Soares; Mello, Carlos Rogerio; Mello, Jose Marcio; Ferraz Filho, Antonio Carlos

    2015-01-01

    The objective of this study was to map the spatial distribution of aboveground carbon stock (using Regression-kriging) of arboreal plants in the Atlantic Forest, Semi-arid woodland, and Savanna Biomes in Minas Gerais State, southeastern Brazil. The database used in this study was obtained from 163 forest fragments, totaling 4,146 plots of 1,000 m2 distributed in these Biomes. A geographical model for carbon stock estimation was parameterized as a function of Biome, latitude and altitude. This model was applied over the samples and the residuals generated were mapped based on geostatistical procedures, selecting the exponential semivariogram theoretical model for conducting ordinary Kriging. The aboveground carbon stock was found to have a greater concentration in the north of the State, where the largest contingent of native vegetation is located, mainly the Savanna Biome, with Wooded Savanna and Shrub Savanna phytophysiognomes. The largest weighted averages of carbon stock per hectare were found in the south-center region (48.6 Mg/ha) and in the southern part of the eastern region (48.4 Mg/ha) of Minas Gerais State, due to the greatest predominance of Atlantic Forest Biome forest fragments. The smallest weighted averages per hectare were found in the central (21.2 Mg/ha), northern (20.4 Mg/ha), and northwestern (20.7 Mg/ha) regions of Minas Gerais State, where Savanna Biome fragments are predominant, in the phytophysiognomes Wooded Savanna and Shrub Savanna.

  3. [Temporal diversity dynamics of the arbuscular mycorrhizal fungi of Larrea tridentata (Sesse & Mocino ex DC) Coville in a semi-arid ecosystem].

    Science.gov (United States)

    Hernández-Zamudio, Genoveva; Sáenz-Mata, Jorge; Moreno-Reséndez, Alejandro; Castañeda-Gaytán, Gamaliel; Ogaz, Alfredo; Carballar-Hernández, Santos; Hernández-Cuevas, Laura

    2017-12-06

    Arbuscular mycorrhizal fungi (AMF) of arid and semiarid ecosystems are important for the development of plants that grow under biotic stress in wild or in agro-ecosystems. There is little information on the temporal diversity of these organisms in perennial plants from arid ecosystems in northern Mexico. On this study, the mycorrhizal colonization and the temporal diversity of AMF in the rhizosphere of Larrea tridentata, perennial plant abundant in the Chihuahuan Desert region were explored. Samples of the rhizosphere and roots of fifteen plants in each of the three sampling dates during the 2015 year were obtained. A total of 17 species of HMA belonging to 12 genera and 7 families within the phylum Glomeromycota in all three sampling dates were found. Funneliformis geosporum was the dominant species belonging to the family Glomeraceae which possess the highest genera number on L. tridentata. The highest mycorrhization percentage was in February with 83.22, followed by September and May with 75.27 and 65.27%, respectively. A maximum of 16 AM fungal species were isolated and identified from L. tridentata rhizosphere in February, 15 species in May and 12 species in September. Statistical analysis showed significant differences between sampling dates in the spores number. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Tectonic setting of the Great Dyke, Chembadzi, Chewore and Atchiza layered complexes in Zimbabwe and Mozambique

    International Nuclear Information System (INIS)

    Master, S.

    1990-01-01

    The Great Dyke of Zimbabwe is one of the largest ultramafic-mafic layered igneous complexexs in the world. Because of the economic importance of large layered intrusions like the Great Dyke, their tectonic setting is of great interest. The Chembadzi complex is a 14 km long, dyke-like layered intrusion up to 800m wide. The Chewore complex, which was thought to have the structure of an irregular lopolith, outcrops over an area of about 200 km in horst blocks in the lower Zambezi Valley in northern Zimbabwe. The Atchiza complex is situated just north of the Cahora Bassa lake and the Zambezi River valley in Mozambique. In considering the tectonic setting of the Great Dyke and its correlatives, most attention has been focussed on events in the Limpopo Mobile Belt, which were responsible for producing the fractures in the Zimbabwe craton that is occupied by the intrusives. 39 refs

  5. Amphibian and reptile biodiversity in the semi-arid region of the municipality of Nopala de Villagrán, Hidalgo, Mexico

    OpenAIRE

    Roth-Monzón, Andrea J.; Mendoza-Hernández, Andrés Alberto; Flores-Villela, Oscar

    2018-01-01

    Current global changes are putting both biodiversity and the processes that depend on it at risk. This is especially true for semi-arid regions and the flagship groups that inhabit them, such as amphibians and reptiles. Semi-arid regions are often thought to have lower biodiversity and thus have been overlooked, resulting in the underestimation of their biological richness. Therefore, the aim of this study was to conduct an inventory of amphibians and reptiles in the semi-arid municipality of...

  6. Effects of different agricultural managements in soil microbial community structure in a semi-arid Mediterranean region.

    Science.gov (United States)

    García-Orenes, Fuensanta; Morugan, Alicia; Mataix-Solera, Jorge; Scow, Kate

    2013-04-01

    Agriculture has been practiced in semi-arid Mediterranean regions for 10.000 years and in many cases these practices have been unsuitable causing land degradation for millennium and an important loss of soil quality. The land management can provide solutions to find the best agricultural practices in order to maintain the soil quality and get a sustainable agriculture model. Microbiological properties are the most sensitive and rapid indicators of soil perturbations and land use managements. The study of microbial community and diversity has an important interest as indicators of changes in soil quality. The main objective of this work was to asses the effect of different agricultural management practices in soil microbial community (evaluated as abundance of phospholipid fatty acids, PLFA). Four different treatments were selected, based on the most commonly practices applied by farmers in the study area, "El Teularet Experimental Station", located at the Enguera Range in the southern part of the Valencia province (eastern Spain). These treatments were: a) ploughing, b) herbicides c) mulch, using the types applied by organic farmers to develop a sustainable agriculture, such as oat straw and d) control that was established as plot where the treatment was abandonment after farming. An adjacent area with the same type of soil, but with natural vegetation was used as a standard or reference high quality soil. Soil samples were taken to evaluate the changes in microbial soil structure, analysing the abundance of PLFA. The results showed a major content of total PLFA in soils treated with oats straw, being these results similar to the content of PLFA in the soil with natural vegetation, also these soils were similar in the distribution of abundance of different PLFA studied. However, the herbicide and tillage treatments showed great differences regarding the soil used as reference (soil under natural vegetation).

  7. A model analysis of climate and CO2 controls on tree growth in a semi-arid woodland

    Science.gov (United States)

    Li, G.; Harrison, S. P.; Prentice, I. C.

    2015-03-01

    We used a light-use efficiency model of photosynthesis coupled with a dynamic carbon allocation and tree-growth model to simulate annual growth of the gymnosperm Callitris columellaris in the semi-arid Great Western Woodlands, Western Australia, over the past 100 years. Parameter values were derived from independent observations except for sapwood specific respiration rate, fine-root turnover time, fine-root specific respiration rate and the ratio of fine-root mass to foliage area, which were estimated by Bayesian optimization. The model reproduced the general pattern of interannual variability in radial growth (tree-ring width), including the response to the shift in precipitation regimes that occurred in the 1960s. Simulated and observed responses to climate were consistent. Both showed a significant positive response of tree-ring width to total photosynthetically active radiation received and to the ratio of modeled actual to equilibrium evapotranspiration, and a significant negative response to vapour pressure deficit. However, the simulations showed an enhancement of radial growth in response to increasing atmospheric CO2 concentration (ppm) ([CO2]) during recent decades that is not present in the observations. The discrepancy disappeared when the model was recalibrated on successive 30-year windows. Then the ratio of fine-root mass to foliage area increases by 14% (from 0.127 to 0.144 kg C m-2) as [CO2] increased while the other three estimated parameters remained constant. The absence of a signal of increasing [CO2] has been noted in many tree-ring records, despite the enhancement of photosynthetic rates and water-use efficiency resulting from increasing [CO2]. Our simulations suggest that this behaviour could be explained as a consequence of a shift towards below-ground carbon allocation.

  8. Accumulation of carbon in northern mire ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, K.; Turunen, J.; Alm, J. [Joensuu Univ. (Finland). Dept. of Biology; Korhola, A. [Helsinki Univ. (Finland). Lab. of Physical Geography; Jungner, H. [Helsinki Univ. (Finland). Dating Lab.; Vasander, H. [Helsinki Univ. (Finland). Dept. of Forest Ecology

    1996-12-31

    The basic feature in the functional ecology of any mire ecosystem is retardation of the effective decay of organic material resulting in a conspicuous accumulation of plant debris as peat overtime. The carbon accumulation process is slow, and climatic change may have an impact on the carbon cycle of peatlands, therefore, it has been of interest to study the rate of carbon accumulation by geological methods from dated peat strata. The approach is hampered by several facts. First, the mires vary enormously as to their vegetation and hydrology and hence their production and decay properties. It follows that a great number of study sites are needed. Second, the peat in mires expands both vertically and laterally, and this requires a spatial reconstruction of carbon accumulation within a mire basin. Third, simple geological methods cannot account for the actual rate of carbon accumulation in peat, and finally, an additional carbon sink in the mire ecosystems can be the mineral subsoil beneath peat. The proposed warming will perhaps shift northwards the existing climatic mire regimes and, thus, the northern aapa fens will change to Sphagnum bogs that are more effective in sequestering carbon, but distinctly less effective in their CH{sub 4} and N{sub 2}O emanation. The role of mire fires in more remote northern areas may then become another important factor. The answer to the important question of future total sequestration of carbon to peatlands depends on the precipitation and its seasonal distribution pattern. Most climatic scenarios predict a decrease in the evaporation surplus during the summer at northern regions. Presumably, the consequent lowering of the water table would improve growth of forest on mires and simultaneously decrease the methane fluxes from peat. The combined net effect could be a clear restraining of the radiative forcing

  9. Accumulation of carbon in northern mire ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, K; Turunen, J; Alm, J [Joensuu Univ. (Finland). Dept. of Biology; Korhola, A [Helsinki Univ. (Finland). Lab. of Physical Geography; Jungner, H [Helsinki Univ. (Finland). Dating Lab.; Vasander, H [Helsinki Univ. (Finland). Dept. of Forest Ecology

    1997-12-31

    The basic feature in the functional ecology of any mire ecosystem is retardation of the effective decay of organic material resulting in a conspicuous accumulation of plant debris as peat overtime. The carbon accumulation process is slow, and climatic change may have an impact on the carbon cycle of peatlands, therefore, it has been of interest to study the rate of carbon accumulation by geological methods from dated peat strata. The approach is hampered by several facts. First, the mires vary enormously as to their vegetation and hydrology and hence their production and decay properties. It follows that a great number of study sites are needed. Second, the peat in mires expands both vertically and laterally, and this requires a spatial reconstruction of carbon accumulation within a mire basin. Third, simple geological methods cannot account for the actual rate of carbon accumulation in peat, and finally, an additional carbon sink in the mire ecosystems can be the mineral subsoil beneath peat. The proposed warming will perhaps shift northwards the existing climatic mire regimes and, thus, the northern aapa fens will change to Sphagnum bogs that are more effective in sequestering carbon, but distinctly less effective in their CH{sub 4} and N{sub 2}O emanation. The role of mire fires in more remote northern areas may then become another important factor. The answer to the important question of future total sequestration of carbon to peatlands depends on the precipitation and its seasonal distribution pattern. Most climatic scenarios predict a decrease in the evaporation surplus during the summer at northern regions. Presumably, the consequent lowering of the water table would improve growth of forest on mires and simultaneously decrease the methane fluxes from peat. The combined net effect could be a clear restraining of the radiative forcing

  10. Land use in the northern Coachella Valley

    Science.gov (United States)

    Bale, J. B.; Bowden, L. W.

    1973-01-01

    Satellite imagery has proved to have great utility for monitoring land use change and as a data source for regional planning. In California, open space desert resources are under severe pressure to serve as a source for recreational gratification to individuals living in the heavily populated southern coastal plain. Concern for these sensitive arid environments has been expressed by both federal and state agencies. The northern half of the Coachella Valley has historically served as a focal point for weekend recreational activity and second homes. Since demand in this area has remained high, land use change from rural to urban residential has been occurring continuously since 1968. This area of rapid change is an ideal site to illustrate the utility of satellite imagery as a data source for planning information, and has served as the areal focus of this investigation.

  11. Radioactivity in Northern Ireland soils - December 1986

    International Nuclear Information System (INIS)

    Jenkins, D.W.K.

    1989-01-01

    The main objective of the survey was to establish the radionuclide content of permanent pasture soils. The extent of contamination from the Chernobyl accident was also studied with the use of Cs-134 as an indicator of Chernobyl fallout. A preliminary radiological assessment was performed by referring to the generalised derived limits. Results of the grassland grid survey show that Chernobyl-derived radiocaesium was widely spread throughout Northern Ireland with the exception of the East Coast where the deposition was more localised reflecting the showery-rainfall pattern on the 3rd May 1986. Accumulation of Chernobyl material showed a high correlation with rainfall on that day, which resulted in a substantial increase in Cs-137 levels compared to estimated pre-Chernobyl concentrations in many areas. The main areas affected lay in a band across the country from the North East to the South with a smaller incursion to the North. The plutonium content in soils from Northern Ireland arising from nuclear weapons fallout was similar to levels found in other surveys completed in Great Britain before Chernobyl. (author)

  12. Proposed artificial recharge studies in northern Qatar

    Science.gov (United States)

    Kimrey, J.O.

    1985-01-01

    The aquifer system in northern Qatar comprises a water-table aquifer in the Rus Formation which is separated by an aquitard from a partially confined aquifer in the top of the overlying Umm er Radhuma Formation. These two aquifers are composed of limestone and dolomite of Eocene and Paleocene age and contain a fragile lens of freshwater which is heavily exploited as a source of water for agricultural irrigation. Net withdrawals are greatly in excess of total recharge, and quality of ground water is declining. Use of desalinated seawater for artificial recharge has been proposed for the area. Artificial recharge, on a large scale, could stabilize the decline in ground-water quality while allowing increased withdrawals for irrigation. The proposal appears technically feasible. Recharge should be by injection to the Umm er Radhuma aquifer whose average transmissivity is about 2,000 meters squared per day (as compared to an average of about 200 meters squared per day for the Rus aquifer). Implementation of artificial recharge should be preceded by a hydrogeologic appraisal. These studies should include test drilling, conventional aquifer tests, and recharge-recovery tests at four sites in northern Qatar. (USGS)

  13. Mapping Soil hydrologic features in a semi-arid irrigated area in Spain

    Science.gov (United States)

    Jiménez-Aguirre, M.° Teresa; Isidoro, Daniel; Usón, Asunción

    2016-04-01

    The lack of soil information is a managerial problem in irrigated areas in Spain. The Violada Irrigation District (VID; 5234 ha) is a gypsic, semi-arid region in the Middle Ebro River Basin, northeast Spain. VID is under irrigation since the 1940's. The implementation of the flood irrigation system gave rise to waterlogging problems, solved along the years with the installation of an artificial drainage network. Aggregated water balances have been performed in VID since the early 1980's considering average soil properties and aggregated irrigation data for the calculations (crop evapotranspiration, canal seepage, and soil drainage). In 2008-2009, 91% of the VID was modernized to sprinkler irrigation. This new system provides detailed irrigation management information that together with detailed soil information would allow for disaggregated water balances for a better understanding of the system. Our goal was to draw a semi-detailed soil map of VID presenting the main soil characteristics related to irrigation management. A second step of the work was to set up pedotransfer functions (PTF) to estimate the water content and saturated hydraulic conductivity (Ks) from easily measurable parameters. Thirty four pits were opened, described and sampled for chemical and physical properties. Thirty three additional auger holes were sampled for water holding capacity (WHC; down to 60 cm), helping to draw the soil units boundaries. And 15 Ks tests (inverse auger hole method) were made. The WHC was determined as the difference between the field capacity (FC) and wilting point (WP) measured in samples dried at 40°C during 5 days. The comparison with old values dried at 105°C for 2 days highlighted the importance of the method when gypsum is present in order to avoid water removal from gypsum molecules. The soil map was drawn down to family level. Thirteen soil units were defined by the combination of five subgroups [Typic Calcixerept (A), Petrocalcic Calcixerept (B), Gypsic

  14. Prospecting for safe (low fluoride groundwater in the Eastern African Rift: the Arumeru District (Northern Tanzania

    Directory of Open Access Journals (Sweden)

    G. Ghiglieri

    2010-06-01

    Full Text Available A multidisciplinary research effort, including geological, hydrogeological, hydro-chemical, geophysical and hydrological investigations, was aimed at locating a source of safe groundwater for a district of northern Tanzania, within the western branch of the East Africa Rift Valley, where water shortage is common and much of the surface water carries unacceptable levels of dissolved fluoride. The 440 km2 study area lies in the northern part of Arumeru district and is dominated by Mt. Meru (4565 m a.s.l.. The local climate is semi-arid, with distinct wet and dry seasons. Four hydrogeological complexes were identified, occurring within different volcanic formations, either alone or superimposed upon one another. The groundwater flow system was interpreted from the spatial distribution of the springs, combined with a lithology- and geometry-based reconstruction of the aquifers. The dominant pattern consists of a multi-directional flow from the higher elevations in the south towards the lower areas in the north, but this is complicated by structures such as grabens, faults, lava domes and tholoids. After the identification of the major fluoride source, an interference pattern between groundwater and high fluoride surface water was drawn. Finally, vertical electrical soundings were performed to define the location of aquifers in regions where release of fluoride was prevented. The methodological approach for the prospecting of safe water in a semi-arid, fluoride polluted region was validated by the drilling of a 60 m deep well capable of supplying at least 3.8 l/s of low fluoride, drinkable water.

  15. Modelling hydrologic and hydrodynamic processes in basins with large semi-arid wetlands

    Science.gov (United States)

    Fleischmann, Ayan; Siqueira, Vinícius; Paris, Adrien; Collischonn, Walter; Paiva, Rodrigo; Pontes, Paulo; Crétaux, Jean-François; Bergé-Nguyen, Muriel; Biancamaria, Sylvain; Gosset, Marielle; Calmant, Stephane; Tanimoun, Bachir

    2018-06-01

    Hydrological and hydrodynamic models are core tools for simulation of large basins and complex river systems associated to wetlands. Recent studies have pointed towards the importance of online coupling strategies, representing feedbacks between floodplain inundation and vertical hydrology. Especially across semi-arid regions, soil-floodplain interactions can be strong. In this study, we included a two-way coupling scheme in a large scale hydrological-hydrodynamic model (MGB) and tested different model structures, in order to assess which processes are important to be simulated in large semi-arid wetlands and how these processes interact with water budget components. To demonstrate benefits from this coupling over a validation case, the model was applied to the Upper Niger River basin encompassing the Niger Inner Delta, a vast semi-arid wetland in the Sahel Desert. Simulation was carried out from 1999 to 2014 with daily TMPA 3B42 precipitation as forcing, using both in-situ and remotely sensed data for calibration and validation. Model outputs were in good agreement with discharge and water levels at stations both upstream and downstream of the Inner Delta (Nash-Sutcliffe Efficiency (NSE) >0.6 for most gauges), as well as for flooded areas within the Delta region (NSE = 0.6; r = 0.85). Model estimates of annual water losses across the Delta varied between 20.1 and 30.6 km3/yr, while annual evapotranspiration ranged between 760 mm/yr and 1130 mm/yr. Evaluation of model structure indicated that representation of both floodplain channels hydrodynamics (storage, bifurcations, lateral connections) and vertical hydrological processes (floodplain water infiltration into soil column; evapotranspiration from soil and vegetation and evaporation of open water) are necessary to correctly simulate flood wave attenuation and evapotranspiration along the basin. Two-way coupled models are necessary to better understand processes in large semi-arid wetlands. Finally, such coupled

  16. 'Great Power Style' in China's Economic Policy

    DEFF Research Database (Denmark)

    Jiang, Yang

    2011-01-01

    China’s ascendance attracts concern, even though Beijing claims to be a responsible great power and tries to demonstrate its ‘great power style’ in economic diplomacy. This article therefore discusses the following questions: to what extent does the current notion and practice of Chinese ‘great...... power style’ in economic diplomacy comply with, or differ from, the criteria of benign hegemony; and what are the major constraining factors? Conceptually, China’s ‘great power style’ is rooted in ancient Chinese political philosophy and institution, but it highly resembles the Western notion of benign...

  17. Evaluation of Sugar Maple Dieback in the Upper Great Lakes Region and Development of a Forest Health Youth Education Program

    Science.gov (United States)

    Bal, Tara L.

    2013-01-01

    Sugar Maple, "Acer saccharum" Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as…

  18. Water in northern Alberta

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    This report contains background information, including historical aspects, roles of government agencies, and relevant technical information, for use as a resource document at a conference on water resources in northern Alberta. An overview is presented of the three river basins which are the geographic focus of this report (Peace River, Athabasca, and Beaver River), describing their characteristics, the types of human activity occurring in them, and the relevant issues pertaining to water. The roles and responsibilities of government departments and agencies in water management are then introduced. A section on water resource issues defines ten topic areas, and for each issue, a summary of the issue, background of the issue, and key concerns and suggested actions are given. These issue areas concern groundwater management (including protection from contamination by oil field produced water), community water supply, farmland drainage and erosion, protection of surface water quality, watershed and wetlands management, farm and rural water supply, tourism/recreation and fisheries, industrial water use (particularly by the oil sand, forestry, and hydroelectric power industries), native peoples' concerns, and water diversion. The final section discusses a number of common themes which arose from the public consultation process, including integrated planning and program coordination, monitoring and enforcement, public information, and research requirements. 22 refs., 8 figs., 3 tabs.

  19. Characterization of the deforestation effect in a semi-arid region by the use of satellite images

    Science.gov (United States)

    Benhanifia, Khatir; Haddouche, Driss; Smahi, Zakaria; Bensaid, Abdelkrim; Hamimed, Abderrahmane

    2004-02-01

    In Algeria, arid and semi-arid regions occupy over than 95% of whole territory. Forests in the semi arid zone constitutes a front face to the advance of the desert towards northern sides. Like in other regions of the world, deforestation phenomenon have a serious consequences on the fragile ecosystem. Severe continuous drought, fires, pasture, insects as well as the absence of a clear forest politics are so many factors that reduced forest areas in this country. However, the conservation of this patrimony must be a priority of any regional development project. This paper describes an evaluating study of the deforestation impact on forests in the region of Djelfa situated in the Saharian Atlas using multitemporal satellite remote sensing data. In order to establish a forest change map, a methodology based on the comparison between normalized difference vegetation indexes (NDVI) generated from satellite images was adopted. For this purpose, a pair of Landsat and (ETM+) images acquired over the region on April 11th, 1987 and march 24th, 2001 have been used. Until being processed, data used have been geometrically and atmospherically corrected. Then, an (NDVI) have been produced for each date. Resulting from compared (NDVI) image presents the forest change map in the study area. Radiometric values of resulting image have been regrouped into three classes according to change types as follow : Increased radiometry = more active vegetation Decreased radiometry = deterioration in vegetation activity Non changed areas = Non changed Investigations made on the terrain permitted to interpret many causes of detected evolutions. Regressive changes were considerable and demonstrates however, the degradation effect on the vegetation state. Some of regressed radiometry are related to forest fires that affected the region in 1994. Almost of regressive changes are due to a deterioration of vegetation caused by multiple factors. Drought, deceases, pasture and infection are considered

  20. Great Expectations for Middle School Counselors

    Science.gov (United States)

    Wright, Robert J.

    2012-01-01

    During the Great Recession, 2008 to 2010, school systems scrambled to balance budgets, and the ratio of counselors to students became even larger. To make matters worse, the Great Recession had a major impact on cuts in educational funding. Budget cutbacks tend to occur where the public will be least likely to notice. The loss of teachers and the…