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881.
Drought is a significant natural hazard that slowly evolves over time. Because of its character, drought is difficult to monitor and impacts are often poorly documented. Agriculture is one of the most sensitive sectors that are prone to drought. The objective of this research is to assess the impacts of drought on soybean production and revenue in Kentucky. Soybeans are one of Kentucky’s most important commodities. In this study, impacts of 1930–1931, 1940–1942, 1952–1955, 1987–1988, 1999–2000, and 2007 droughts were considered. It was found that over the recent years, up to 56 % of the revenue from soybeans was lost due to drought. During the first half of the twentieth century, revenue loss reached up to 77 %. This research is valuable to the general public as well as planners and policy makers. Proper documentation of impacts of past droughts will help identify drought vulnerabilities and results in better risk management and mitigation. 相似文献
882.
Svetlana V. Degteva Vasily I. Ponomarev Sasha W. Eisenman Vyacheslav Dushenkov 《Ambio》2015,44(6):473-490
Increasing anthropogenic pressure on the largest remaining tracts of old-growth boreal forest in Europe necessitates additional conservation of ecosystems and biodiversity in northeastern European Russia. In a regional network comprising 8 % of the Nenets Autonomous District and 13.5 % of the Komi Republic, 248 areas have varying protected statuses as state nature reserves (zapovedniks), national parks, reserves/sanctuaries (zakazniks), or natural monuments. Due to increased natural resource extraction in this relatively pristine area, designation of additional protected areas is critical for the protection of key ecological sites. The history of ecological preservation in these regions is herein described, and recent recommendations for incorporating additional ecologically representative areas into the regional network are presented. If the protected area network can be expanded, the overall environmental stability in these globally significant ecosystems may remain intact, and can help Russia meet the 2020 Aichi conservation targets, as set forth by the Convention of Biological Diversity. 相似文献
883.
Estimating Remediation and Contaminant Respiration Emissions for Alternatives Comparisons at Petroleum Spill Sites
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Greenhouse gas emissions assessments for site cleanups typically quantify emissions associated with remediation and not those from contaminant biodegradation. Yet, at petroleum spill sites, these emissions can be significant, and some remedial actions can decrease this additional component of the environmental footprint. This article demonstrates an emissions assessment for a hypothetical site, using the following technologies as examples: excavation with disposal to a landfill, light nonaqueous‐phase liquid (LNAPL) recovery with and without recovered product recycling, passive bioventing, and monitored natural attenuation (MNA). While the emissions associated with remediation for LNAPL recovery are greater than the other considered alternatives, this technology is comparable to excavation when a credit associated with product recycling is counted. Passive bioventing, a green remedial alternative, has greater remedial emissions than MNA, but unlike MNA can decrease contaminant‐related emissions by converting subsurface methane to carbon dioxide. For the presented example, passive bioventing has the lowest total emissions of all technologies considered. This illustrates the value in estimating both remediation and contaminant respiration emissions for petroleum spill sites, so that the benefit of green remedial approaches can be quantified at the remedial alternatives selection stage rather than simply as best management practices. ©2015 Wiley Periodicals, Inc. 相似文献
884.
885.
Canhada João C. S. Paiva Fábio F. G. Shinohara Gabriel M. M. Okimoto Fernando Hiranobe Carlos T. Teixeira Silvio R. Job Aldo E. Santos Renivaldo J. 《Journal of Material Cycles and Waste Management》2023,25(2):944-953
Journal of Material Cycles and Waste Management - Leather production is a technology that boosts the economy because of its versatility and durability. However, the wastes generated throughout the... 相似文献
886.
Lunag Marcelino N. Abana Alexander S. Agcaoili Juco P. Arellano Jillien Kaith T. Caluza Coleen Angela G. Decena Nick Brylle V. Paz Emmanuel R. Dela Delgado Lyka Angela B. Obero Aaron F. Ocampo Don Miguel E. Sacdalan Charlene Ann D. 《Journal of Material Cycles and Waste Management》2023,25(2):1216-1226
Journal of Material Cycles and Waste Management - The daily use of facemask to prevent virus transmission increases the negative effect on the environment because of improper waste disposal. Due to... 相似文献
887.
Junga Petr Trávníček Petr Suchý Pavel Kotek Luboš Vítěz Tomáš 《Journal of Material Cycles and Waste Management》2023,25(1):288-301
Journal of Material Cycles and Waste Management - This work focuses on the issue of emergency prevention in the operation of municipal solid waste landfills. In this work, an emergency is... 相似文献
888.
Cristina E. Almeida-Naranjo Bryan Morillo María B. Aldás Nicole Garcés Alexis Debut Victor H. Guerrero 《补救:环境净化治理成本、技术与工艺杂志》2023,33(2):135-150
The removal of heavy metals from wastewater has become a global challenge, which demands the continuous study of efficient and low-cost treatment alternatives such as adsorption. In this research, the removal of zinc was evaluated using batch adsorption processes with nonconventional materials such as graphene oxide (GO), magnetite (MG), and their composites (GO:MG), formulated with three weight ratios (2:1, 1:1, and 1:2). Graphene was synthesized by the modified Marcano method, using pencil lead graphite as a precursor. MG and the composites were synthesized by chemical coprecipitation of ferrous sulfate and ferric chloride. The materials were characterized by Raman and Fourier transform infrared spectroscopies, scanning electron microscopy, X-ray diffraction, and the Brunauer–Emmett–Teller method to determine the functional groups, microstructural and morphological characteristics, and specific surface area. Batch adsorption tests were carried out to optimize the adsorbent dose and contact time with zinc solutions of 10 ppm. Zinc adsorption reached equilibrium at 2 h, with an optimal dose between 0.25 and 1.0 g/L. The maximum zinc removal efficiencies/adsorption capacities were 98.6%/165.6, 83.4%/47.6, 83.5%/21.9, 72.8%/19.9, and 82.2%/9.25 mg/g using GO, 2GO:1MG, 1GO:1MG, 1GO:2MG, and MG, respectively. Furthermore, the analysis of the isotherm and adsorption kinetics models determined that the adsorption processes using MG and the composites fit the Sips and pseudo-second-order models. 相似文献
889.
敌敌畏农药是一种广泛使用的中等毒性的有机磷农药,采用传统方法测定难以满足现场测定的需要。试验以戊二醛为交联剂制备了一种基于丁酰胆碱脂酶的ISFET(离子敏场效应管)生物传感器,并将其应用于敌敌畏的测定,考察了不同pH值、底物浓度、抑制时间等对传感器响应(电压)值的影响,得到了最佳测定条件。 相似文献
890.
Robyn E. Tuerena Claire Mahaffey Sian F. Henley Camille de la Vega Louisa Norman Tim Brand Tina Sanders Margot Debyser Kirstin Dhnke Judith Braun Christian Mrz 《Ambio》2022,51(2):355
Climate change is altering nutrient cycling within the Arctic Ocean, having knock-on effects to Arctic ecosystems. Primary production in the Arctic is principally nitrogen-limited, particularly in the western Pacific-dominated regions where denitrification exacerbates nitrogen loss. The nutrient status of the eastern Eurasian Arctic remains under debate. In the Barents Sea, primary production has increased by 88% since 1998. To support this rapid increase in productivity, either the standing stock of nutrients has been depleted, or the external nutrient supply has increased. Atlantic water inflow, enhanced mixing, benthic nitrogen cycling, and land–ocean interaction have the potential to alter the nutrient supply through addition, dilution or removal. Here we use new datasets from the Changing Arctic Ocean program alongside historical datasets to assess how nitrate and phosphate concentrations may be changing in response to these processes. We highlight how nutrient dynamics may continue to change, why this is important for regional and international policy-making and suggest relevant research priorities for the future.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01673-0. 相似文献