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971.
972.
Hideaki Shibata Cristina Branquinho William H. McDowell Myron J. Mitchell Don T. Monteith Jianwu Tang Lauri Arvola Cristina Cruz Daniela F. Cusack Lubos Halada Ji?í Kopá?ek Cristina Máguas Samson Sajidu Hendrik Schubert Naoko Tokuchi Jaroslav Záhora 《Ambio》2015,44(3):178-193
Anthropogenically derived nitrogen (N) has a central role in global environmental changes, including climate change, biodiversity loss, air pollution, greenhouse gas emission, water pollution, as well as food production and human health. Current understanding of the biogeochemical processes that govern the N cycle in coupled human–ecological systems around the globe is drawn largely from the long-term ecological monitoring and experimental studies. Here, we review spatial and temporal patterns and trends in reactive N emissions, and the interactions between N and other important elements that dictate their delivery from terrestrial to aquatic ecosystems, and the impacts of N on biodiversity and human society. Integrated international and long-term collaborative studies covering research gaps will reduce uncertainties and promote further understanding of the nitrogen cycle in various ecosystems. 相似文献
973.
Digital technology and the conservation of nature 总被引:1,自引:0,他引:1
Digital technology is changing nature conservation in increasingly profound ways. We describe this impact and its significance through the concept of ‘digital conservation’, which we found to comprise five pivotal dimensions: data on nature, data on people, data integration and analysis, communication and experience, and participatory governance. Examining digital innovation in nature conservation and addressing how its development, implementation and diffusion may be steered, we warn against hypes, techno-fix thinking, good news narratives and unverified assumptions. We identify a need for rigorous evaluation, more comprehensive consideration of social exclusion, frameworks for regulation and increased multi-sector as well as multi-discipline awareness and cooperation. Along the way, digital technology may best be reconceptualised by conservationists from something that is either good or bad, to a dual-faced force in need of guidance. 相似文献
974.
Junna Xin Pei Zhang Michael P. Wolcott Jinwen Zhang William C. Hiscox Xiao Zhang 《Journal of Polymers and the Environment》2017,25(3):599-605
In this work, a novel two-step process to prepare primary lignin amine was developed. The lignin used in this study was obtained from the residue of cellulosic sugar fermentation for bioethanol (referred as “lignin”). The lignin was initially oxidized through Fenton oxidation. The oxidized lignin was further converted to lignin amine by reductive amination. Ammonia was used in the second step leading to give the highly active primary lignin amine. The oxidation and reduction exhibited relatively high yields of 80.0 and 91.2 % respectively. For comparison, lignin was partially depolymerized via mild hydrogenolysis and then the partial depolymerized lignin was also converted to lignin amine using the same method. The obtained lignin amines were characterized in detail using elemental analysis, proton nuclear magnetic resonance (1H NMR), and Fourier transform infrared spectroscopy (FTIR). Further, modification of soy protein adhesive by lignin amine was exemplified in wood bonding, and the results indicated that addition of lignin amine greatly increased water resistance of soy protein adhesives. 相似文献
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Mark E. Paddrik Richard Haynes Andrew E. Todd William T. Scherer Peter A. Beling 《The Environmentalist》2016,36(2):167-182
Electronic markets and automated trading have resulted in a drastic increase in the quantity and complexity of regulatory data. Reconstructing the limit order book and analyzing order flow is an emerging challenge for financial regulators. New order types, intra-market behavior, and other exchange functionality further complicate the task of understanding market behavior at multiple levels. Data visualizations have proven to be a fundamental tool for building intuition and enabling exploratory data analysis in many fields. In this paper, we propose the incorporation of visualizations in the workflow of multiple financial regulatory roles, including market surveillance, enforcement and supporting academic research. 相似文献
979.
Jennifer L. Cochran‐Biederman Katherine E. Wyman William E. French Grace L. Loppnow 《Conservation biology》2015,29(1):175-186
Reintroduction of imperiled native freshwater fish is becoming an increasingly important conservation tool amidst persistent anthropogenic pressures and new threats related to climate change. We summarized trends in native fish reintroductions in the current literature, identified predictors of reintroduction outcome, and devised recommendations for managers attempting future native fish reintroductions. We constructed random forest classifications using data from 260 published case studies of native fish reintroductions to estimate the effectiveness of variables in predicting reintroduction outcome. The outcome of each case was assigned as a success or failure on the basis of the author's perception of the outcome and on whether or not survival, spawning, or recruitment were documented during post‐reintroduction monitoring. Inadequately addressing the initial cause of decline was the best predictor of reintroduction failure. Variables associated with habitat (e.g., water quality, prey availability) were also good predictors of reintroduction outcomes, followed by variables associated with stocking (e.g., genetic diversity of stock source, duration of stocking event). Consideration of these variables by managers during the planning process may increase the likelihood for successful outcomes in future reintroduction attempts of native freshwater fish. Identificación de Correlaciones de Éxito y Fracaso de Reintroducciones de Peces de Nativos Agua Dulce 相似文献
980.
Ayesha I.T. Tulloch Richard F. Maloney Liana N. Joseph Joseph R. Bennett Martina M.I. Di Fonzo William J.M. Probert Shaun M. O'Connor Jodie P. Densem Hugh P. Possingham 《Conservation biology》2015,29(2):513-524
Conservation outcomes are uncertain. Agencies making decisions about what threat mitigation actions to take to save which species frequently face the dilemma of whether to invest in actions with high probability of success and guaranteed benefits or to choose projects with a greater risk of failure that might provide higher benefits if they succeed. The answer to this dilemma lies in the decision maker's aversion to risk—their unwillingness to accept uncertain outcomes. Little guidance exists on how risk preferences affect conservation investment priorities. Using a prioritization approach based on cost effectiveness, we compared 2 approaches: a conservative probability threshold approach that excludes investment in projects with a risk of management failure greater than a fixed level, and a variance‐discounting heuristic used in economics that explicitly accounts for risk tolerance and the probabilities of management success and failure. We applied both approaches to prioritizing projects for 700 of New Zealand's threatened species across 8303 management actions. Both decision makers’ risk tolerance and our choice of approach to dealing with risk preferences drove the prioritization solution (i.e., the species selected for management). Use of a probability threshold minimized uncertainty, but more expensive projects were selected than with variance discounting, which maximized expected benefits by selecting the management of species with higher extinction risk and higher conservation value. Explicitly incorporating risk preferences within the decision making process reduced the number of species expected to be safe from extinction because lower risk tolerance resulted in more species being excluded from management, but the approach allowed decision makers to choose a level of acceptable risk that fit with their ability to accommodate failure. We argue for transparency in risk tolerance and recommend that decision makers accept risk in an adaptive management framework to maximize benefits and avoid potential extinctions due to inefficient allocation of limited resources. El Efecto de la Aversión de Riesgo sobre la Priorización de Proyectos de Conservación 相似文献