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771.
Land take and food security: assessment of land take on the agricultural production in Europe 总被引:1,自引:0,他引:1
Ciro Gardi Panos Panagos Marc Van Liedekerke Claudio Bosco Delphine De Brogniez 《Journal of Environmental Planning and Management》2015,58(5):898-912
Soil is a multifunctional, non-renewable natural resource for Europe as clearly expressed in the European Union (EU) Thematic Strategy for Soil Protection (COM (2006)231). Soil carries out multiple functions, including the support of food production. Urban development and its associated land take poses a major threat to soil and could have significant effects on agricultural production. This paper aims to evaluate the potential productivity losses in European agriculture due to land-take processes between 1990 and 2006. Agricultural land take was calculated using CORINE Land Cover maps of 1990, 2000 and 2006. For 21 of the 27 EU member states, agricultural land take was computed to be 752,973 ha for 1990–2000 and 436,095 ha for 2000–2006, representing 70.8% and 53.5%, respectively, of the total EU land take for these periods. The impact of this land take on the production capabilities of the agricultural sector for the period 1990–2006 for 19 of the 21 states was estimated to be equivalent to a loss of more than six million tonnes of wheat. The paper demonstrates that Europe's intense urbanisation has a direct impact on its capability to produce food. 相似文献
772.
Spatial distribution of archaeal and bacterial ammonia oxidizers in the littoral buffer zone of a nitrogen-rich lake 总被引:3,自引:0,他引:3
Yu Wang Guibing Zhu Lei Ye Xiaojuan Feng Huub J. M. Op den Camp Chengqing Yin 《环境科学学报(英文版)》2012,24(5):790-799
The spatial distribution and diversity of archaeal and bacterial ammonia oxidizers (AOA and AOB) were evaluated targeting amoA genes in the gradient of a littoral buffer zone which has been identified as a hot spot for N cycling. Here we found high spatial heterogeneity in the nitrification rate and abundance of ammonia oxidizers in the five sampling sites. The bacterial amoA gene was numerically dominant in most of the surface soil but decreased dramatically in deep layers. Higher nitrification potentials were detected in two sites near the land/water interface at 4.4-6.1 μg NO2--N/(g dry weight soil·hr), while only 1.0-1.7 μg NO2--N/(g dry weight soil·hr) was measured at other sites. The potential nitrification rates were proportional to the amoA gene abundance for AOB, but with no significant correlation with AOA. The NH4 + concentration was the most determinative parameter for the abundance of AOB and potential nitrification rates in this study. Higher richness in the surface layer was found in the analysis of biodiversity. Phylogenetic analysis revealed that most of the bacterial amoA sequences in surface soil were affiliated with the genus of Nitrosopira while the archaeal sequences were almost equally affiliated with Candidatus ‘Nitrososphaera gargensis’ and Candidatus ‘Nitrosocaldus yellowstonii’. The spatial distribution of AOA and AOB indicated that bacteria may play a more important role in nitrification in the littoral buffer zone of a N-rich lake. 相似文献
773.
Amanda N. Van Buskirk Bertram Bynum Boley Charlie H. Killmaster Kristina L. Johannsen Gino J. D'Angelo 《Conservation biology》2023,37(3):e14028
Citizen science (CS) is gaining recognition as a valuable approach to meet data needs for environmental projects while fostering collaboration between scientists and members of the public. Despite increasing implementation of CS by natural resource entities, organizations’ motivations for engaging in CS remain poorly understood. We examined the utility of the theory of planned behavior (TPB) and social exchange theory (SET) in identifying factors influencing support of CS by scientific organizations. To test predictions of the TPB and SET theories, we surveyed (quantitative, web based) state wildlife agency staff in the United States on their perceptions of organizational engagement in CS. We divided questions that measured TPB items into individual and organizational components to address the influence of personal- and organization-level decision-making on staff perceptions and attitudes. We used structural equation modeling to identify key constructs that influence staff support of CS in state wildlife agencies. The survey yielded 627 responses across 44 states. Both TPB and SET constructs accurately predicted staff support of CS; however, measures from SET (e.g., public engagement benefits and costs of CS to scientific credibility) were most influential (i.e., TPB constructs had less impact). Our findings indicate that organizational support for CS is primarily influenced by assessment of trade-offs among perceived costs and benefits. Indicators of support for CS were further elucidated by including measures from the TPB model. Based on our results, we suggest that natural resource entities give careful consideration to CS project design, develop thorough communication and data management plans, and practice iterative evaluation of CS project productivity. 相似文献
774.
Nguyen Trinh Duy Lee Taeyoon Van Tran Thuan Nguyen Vinh Huu Nong Linh Xuan Bach Long Giang Vo Dai-Viet N. 《Environmental Chemistry Letters》2023,21(2):935-980
Environmental Chemistry Letters - Pollution of waste and natural waters by antibiotics is a major health issue that induces the development of resistant pathogens. Pollutant may be removed by... 相似文献
775.
Two field studies of interpersonal conflict in organizations and a simulated dyadic negotiation show that problem solving and forcing are frequently combined simultaneously and sequentially. As a robust finding, conglomerations of problem solving and forcing appear to enhance the parties' joint effectiveness. The best substantive and relational outcomes for the organization are reached through forcing followed by problem solving. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
776.
This study addresses spontaneous inferences about causes and consequences of performance‐related behavior of leaders and subordinates. Respondents (leaders and subordinates) completed sentences describing the behavior of leaders or subordinates. It was expected that behavior of leaders induces more causal analysis because it can more strongly affect others. This hypothesis was confirmed, suggesting that position labels can trigger control motivation. It was also found that leader behavior induced more inferences about the consequences for the environment than for the actor, supporting the assumption that leaders are seen as persons who affect their environment. In addition, the data indicate that subordinate respondents made more inferences about causes as well as consequences than leaders did, and have a more positive view of others. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
777.
Tamera Van Horn 《环境质量管理》2000,9(3):59-63
Colorado's Environmental Leadership Program is based on collaboration, flexibility, and innovation. It may offer a glimpse of what the future of environmental protection could look like. © 2000 John Wiley & Sons, Inc. 相似文献
778.
R. Herrmann R. Stottlemyer J. C. Zak R. L. Edmonds H. Van Miegroet 《Journal of the American Water Resources Association》2000,36(2):337-346
ABSTRACT: Federal parks and other public lands have unique mandates and rules regulating their use and conservation. Because of variation in their response to local, regional, and global‐scale disturbance, development of mitigation strategies requires substantial research in the context of long‐term inventory and monitoring. In 1982, the National Park Service began long‐term, watershed‐level studies in a series of national parks. The objective was to provide a more comprehensive database against which the effects of global change and other issues could be quantified. A subset of five sites in North Carolina, Texas, Washington, Michigan, and Alaska, is examined here. During the last 50 years, temperatures have declined at the southern sites and increased at the northern sites with the greatest increase in Alaska. Only the most southern site has shown an increase in precipitation amount. The net effect of these trends, especially for the most northern and southern sites, would likely be an increase in the growing season and especially the time soil processes could continue without moisture or temperature limitations. During the last 18 years, there were few trends in atmospheric ion inputs. The most evident was the decline in SO42 deposition. There were no significant relationships between ion input and stream water output. This finding suggests other factors as modification of precipitation or canopy throughfall by soil processes, hydrologic flow path, and snowmelt rates are major processes regulating stream water chemical outputs. 相似文献
779.
Alaa Ali Wossenu Abtew Stuart Van Horn Nagendra Khanal 《Journal of the American Water Resources Association》2000,36(4):833-848
requency evaluation and spatial characterization of rainfall in Central and South Florida are presented. Point frequency analysis performed at all available sites has shown that the 2‐parameter Gamma probability density function is the best model for monthly rainfall frequency over Central and South Florida. The model's parameters estimated at 145 stations were used to provide monthly rainfall estimates for 10‐ and 100‐year dry and wet return periods. Experimental and theoretical variograms computed for these estimates, as well as the Kriging estimation variance maps, show that the existing rain gage network is less capable of resolving monthly rainfall variation in the wet season than the dry season. May is the dry‐to‐wet transition month, while October is the wet‐to‐dry transition month with average rainfall of 4.5 inches. Monthly average rainfall is above 7 inches during the wet season and below 3 inches during the dry season. Two‐thirds of the annual rainfall is accumulated in the wet season. Annual average rainfall is maximum (above 60 inches) in many areas along the east coast, and is minimum (below 45 inches) in many areas over Lake Okee‐chobee and Central Florida. Rainfall maps show a changing pattern between the wet and the dry seasons. Frontal rainfall occurs in the dry season, while convective rainfall, tropical depression, and hurricanes occur in the wet season. Average rainfall is higher along the east coast area in the dry season and it is higher along the west coast area in the wet season. 相似文献
780.
Catherine Chamberlin Marilyn ten Brink Kate Munson Alyssa Le Naomi Detenbeck 《Journal of the American Water Resources Association》2023,59(1):178-196
Excess loading of nitrogen and phosphorus to river networks causes environmental harm, but reducing loads from large river basins is difficult and expensive. We developed a new tool, the River Basin Export Reduction Optimization Support Tool (RBEROST) to identify the least-cost combinations of management practices that will reduce nutrient loading to target levels in downstream and mid-network waterbodies. We demonstrate the utility of the tool in a case study in the Upper Connecticut River Basin in New England, USA. The total project cost of optimized lowest-cost plans ranged from $18.0 million to $41.0 million per year over 15 years depending on user specifications. Plans include both point source and non-point source management practices, and most costs are associated with urban stormwater practices. Adding a 2% margin of safety to loading targets improved the estimated probability of success from 37.5% to 99%. The large spatial scale of RBEROST, and the consideration of both point and non-point source contributions of nutrients, make it well suited as an initial screening tool in watershed planning. 相似文献