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951.
Factors influencing farmers’ decisions on nitrogen fertilizer application in the Liangzihu Lake basin,Central China 总被引:3,自引:0,他引:3
Jin Zhang Günther Manske Pi Qi Zhou Bernhard Tischbein Mathias Becker Zhao Hua Li 《Environment, Development and Sustainability》2017,19(3):791-805
Overuse of nitrogen (N) fertilizers in agriculture activities has caused severe water pollution in China. The lack of data at producer level hampers decision makers in the development and implementation of efficient policies to curb excessive N-fertilizer use. In a survey of 300 farm households in the Liangzihu Lake basin, we identified factors associated with farmers’ decisions on N-fertilizer use and application rate. Household survey and multiple linear regression models indicate that the average application rate in the study region is 229 kg N ha?1, which exceeds the recommended rate for maximum profit for cereal crops (maize, wheat, and rice) in China of 150–180 kg N ha?1. High N-application rates are associated with low farmland productivity (coefficient = ?15.66, p = 0.02), a high share of off-farm income (coefficient = 27.14, p = 0.003), and a low education level of the household head (coefficient = ?10.83, p = 0.039). Neither physical infrastructure nor access to input markets appears to be related to N-application rates. It may be concluded that excessive use of N in agriculture of Central China is mainly a problem of insufficient awareness and high share of off-farm income. 相似文献
952.
953.
Trends in the dynamics of herbivore community related to trophic competition in summer have been analyzed on Wrangel Island. The results show that the trophic spectra overlap considerably, resources are partitioned on the principle “weak competitors after strong competitors,” and community dynamics in the absence of extermination depend on specific competitive advantages related to the width of food spectrum. We conclude that the dynamics of this insular community prior to the establishment of nature reserve on the island have been determined by human activities, as well as the structure of arctic herbivore communities in general. 相似文献
954.
Jonathan M. H. Green Gemma R. Cranston William J. Sutherland Hannah R. Tranter Sarah J. Bell Tim G. Benton Eva Blixt Colm Bowe Sarah Broadley Andrew Brown Chris Brown Neil Burns David Butler Hannah Collins Helen Crowley Justin DeKoszmovszky Les G. Firbank Brett Fulford Toby A. Gardner Rosemary S. Hails Sharla Halvorson Michael Jack Ben Kerrison Lenny S. C. Koh Steven C. Lang Emily J. McKenzie Pablo Monsivais Timothy O’Riordan Jeremy Osborn Stephen Oswald Emma Price Thomas David Raffaelli Belinda Reyers Jagjit S. Srai Bernardo B. N. Strassburg David Webster Ruth Welters Gail Whiteman James Wilsdon Bhaskar Vira 《Sustainability Science》2017,12(2):319-331
Delivering access to sufficient food, energy and water resources to ensure human wellbeing is a major concern for governments worldwide. However, it is crucial to account for the ‘nexus’ of interactions between these natural resources and the consequent implications for human wellbeing. The private sector has a critical role in driving positive change towards more sustainable nexus management and could reap considerable benefits from collaboration with researchers to devise solutions to some of the foremost sustainability challenges of today. Yet opportunities are missed because the private sector is rarely involved in the formulation of deliverable research priorities. We convened senior research scientists and influential business leaders to collaboratively identify the top forty questions that, if answered, would best help companies understand and manage their food-energy-water-environment nexus dependencies and impacts. Codification of the top order nexus themes highlighted research priorities around development of pragmatic yet credible tools that allow businesses to incorporate nexus interactions into their decision-making; demonstration of the business case for more sustainable nexus management; identification of the most effective levers for behaviour change; and understanding incentives or circumstances that allow individuals and businesses to take a leadership stance. Greater investment in the complex but productive relations between the private sector and research community will create deeper and more meaningful collaboration and cooperation. 相似文献
955.
Huber Nica Hergert Rico Price Bronwyn Zäch Christian Hersperger Anna M. Pütz Marco Kienast Felix Bolliger Janine 《Regional Environmental Change》2017,17(4):1241-1255
Regional Environmental Change - Replacement of conventional energy sources with renewables such as solar panels and wind turbines requires adequate land. Impact assessments should be conducted to... 相似文献
956.
Loran Christin Munteanu Catalina Verburg Peter H. Schmatz Dirk R. Bürgi Matthias Zimmermann Niklaus E. 《Regional Environmental Change》2017,17(8):2223-2235
Regional Environmental Change - The spatial distribution of forests in Europe represents the legacy of centuries of human land use decisions. Due to the limited availability of historical data,... 相似文献
957.
Feurdean Angelica Munteanu Catalina Kuemmerle Tobias Nielsen Anne B. Hutchinson Simon M. Ruprecht Eszter Parr Catherine L. Perşoiu Aurel Hickler Thomas 《Regional Environmental Change》2017,17(8):2193-2207
Regional Environmental Change - Traditional farming landscapes in the temperate zone that have persisted for millennia can be exceptionally species-rich and are therefore key conservation targets.... 相似文献
958.
How can public engagement assist in the development of just processes and outcomes in adaptation discourse and policymaking? A concern with justice is at the center of thinking about adaptation that is not only resilient, but also public, engaging, and transformative. Theoretically, the intersection of adaptation, transformation, and environmental and climate justice is examined, before exploring the specific concerns and normative foundations for adaptation policy articulated by local governments, environmental groups, and local residents engaged in adaptation planning in Australia. Despite a discursive disconnect between governmental focus on a risk or resilience-based approach and a community concern with the vulnerability of basic needs and capabilities of everyday life, deliberative engagement in adaptation planning can both address issues of justice and represent a transformative practice. 相似文献
959.
The Deepwater Horizon oil spill occurred in the Gulf of Mexico on April 20, 2010. Considered the largest accidental marine oil spill in history, oil flowed for three months and approximately five million barrels of oil spilled through by mid-July 2010. In this article, we analyze bird data to assess the impact of the oil spill on the Gulf wildlife. Particularly, we want to determine in which regions Laughing Gulls were mostly affected by the oil spill, and whether those regions spatially shifted throughout the year 2010. Though our data sets have some limitations to apply statistical analysis methods, we obtained very interesting results. Our analyses showed the general consistency of the results based on two population data sets (from the 2011 Data Expo and from the eBird community) and justified the use of both publicly available data sets. We showed that the closer the surface oil spill area approached to the Laughing Gulls habitats, the more significant clusters of bird cases were observed. 相似文献
960.
Manuel Vonrüti Aleksandar Spasojevic Nils Nölke Thomas Kneib Christoph Kleinn 《Environmental and Ecological Statistics》2017,24(3):385-398
Temperature is an important physical factor that is known to strongly affect biodiversity as well as ecosystems and their functioning. However, research in this area is still relatively limited; this may also be attributed to the multitude of influencing factors and the complexity of the statistics involved. This study analyzes the differences between the surface temperature of three Central European broadleaf tree species. A better understanding of these differences may help to elucidate the role of microclimate in biodiversity. We consider a time series of high-resolution thermal images taken from a meteorological observation tower and calculate mean canopy leaf temperatures for beech, ash and maple (Fagus silvatica, Fraxinus excelsior and Acer pseudoplatanus). In a first step, comparable image areas are extracted from the thermal image sections of the crown of each tree species avoiding shadow areas, branches, etc. We used an automatic segmentation technique, the Otsu thresholding. Extracted canopy leaf temperature values were then processed and the resulting temperature profiles estimated by O’Sullivan penalized splines. For comparing the differences in canopy leaf temperature over time, we propose the construction of simultaneous confidence bands. The analyses show that there are significant—though small—differences in canopy surface temperature between the three tree species. 相似文献