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961.
Fabrizia Ratto Tom D. Breeze Lorna J. Cole Michael P. D. Garratt David Kleijn Bill Kunin Denis Michez Rory O'Connor Jeff Ollerton Robert J. Paxton Guy M. Poppy Simon G. Potts Deepa Senapathi Rosalind Shaw Lynn V. Dicks Kelvin S.-H. Peh 《Conservation biology》2022,36(4):e13886
Pollinator declines have prompted efforts to assess how land-use change affects insect pollinators and pollination services in agricultural landscapes. Yet many tools to measure insect pollination services require substantial landscape-scale data and technical expertise. In expert workshops, 3 straightforward methods (desk-based method, field survey, and empirical manipulation with exclusion experiments) for rapid insect pollination assessment at site scale were developed to provide an adaptable framework that is accessible to nonspecialist with limited resources. These methods were designed for TESSA (Toolkit for Ecosystem Service Site-Based Assessment) and allow comparative assessment of pollination services at a site of conservation interest and in its most plausible alternative state (e.g., converted to agricultural land). We applied the methods at a nature reserve in the United Kingdom to estimate the value of insect pollination services provided by the reserve. The economic value of pollination services provided by the reserve ranged from US$6163 to US$11,546/year. The conversion of the reserve to arable land would provide no insect pollination services and a net annual benefit from insect-pollinated crop production of approximately $1542/year (US$24∙ha–1∙year–1). The methods had wide applicability and were readily adapted to different insect-pollinated crops: rape (Brassica napus) and beans (Vicia faba) crops. All methods were rapidly employed under a low budget. The relatively less robust methods that required fewer resources yielded higher estimates of annual insect pollination benefit. 相似文献
962.
Santana Antônio H. Araújo José A. S. Bento Amanda M. S. Santos Ana R. Santos Leocácia G. Gomes Hiago de O. da Costa José Galberto M. Menezes Jorge Marcell C. Coutinho Henrique Douglas Melo Filho Francisco José de P. Teixeira Raimundo Nonato P. 《Environmental geochemistry and health》2021,43(4):1583-1597
Environmental Geochemistry and Health - The contamination of bodies of water by potentially hazardous elements has in recent decades become an environmental problem that poses serious risks to... 相似文献
963.
气相色谱法观测本底大气中的甲烷和二氧化碳 总被引:19,自引:6,他引:19
根据世界气象组织全球大气监测(WMO/GAW)开展全球温室气体监测的要求,建立了气相色谱(GC)法甲烷和二氧化碳(CH4/CO2)连续观测系统,概述了该系统厍拿大大气环境局(AES)5个月的组装调试,以及在中国大气本底基准台(CGAWBO_一年多时间里的业务运行和标定情况,且装调试和运动标定,与红餐吸收(NDIR)法,气瓶采样-实验室分析(FLASK)法数据,以及与上其它台站观测资料的对比结果表明 相似文献
964.
Simba Tirim Casey Bartrem Ian von Lindern Margrit von Braun Douglas Lin Shehu Mohamed Ank Aishat Abdullahi 《环境科学学报(英文版)》2018,30(5):260-272
In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put residents, especially children, at the highest risk. Principal routes of exposure were incidental ingestion and inhalation of contaminated soil and dusts. Several Nigerian and international health organizations collaborated to reduce lead exposures through environmental remediation and medical treatment. The contribution of contaminated food to total lead exposure was assessed during the environmental health response. Objectives of this investigation were to assess the influence of cultural/dietary habits on lead exposure pathways and estimate the contribution of contaminated food to children's blood lead levels(BLLs). A survey of village dietary practices and staple food lead content was conducted to determine dietary composition, caloric intakes, and lead intake. Potential blood lead increments were estimated using bio-kinetic modeling techniques. Most dietary lead exposure was associated with contamination of staple cereal grains and legumes during post-harvest processing and preparation in contaminated homes. Average post-harvest and processed cereal grain lead levels were 0.32 mg/kg and 0.85 mg/kg dry weight, respectively. Age-specific food lead intake ranged from 7 to 78 μg/day. Lead ingestion and absorption were likely aggravated by the dusty environment, fasting between meals, and nutritional deficiencies. Contamination of staple cereal grains by highly bioavailable pulverized ores could account for as much as 11%–34% of children's BLLs during the epidemic, and were a continuing source after residential soil remediation until stored grain inventories were exhausted. 相似文献
965.
Gregory S. Douglas Jeffery H. Hardenstine Roopa Kamath Deyuan Kong Robert E. Hoffmann Sara McMillen 《补救:环境净化治理成本、技术与工艺杂志》2020,30(4):27-37
Bioremediation is a proven alternative for remediating petroleum‐impacted soils at exploration and production (E&P) sites. Monitoring remediation performance can involve detection and quantification of biodegradation resistant compounds such as C3017α(H),21β(H)‐hopane, which requires the use of gas chromatography with mass spectrometry detection (GC/MS). Due to the remoteness of many E&P sites, this technology is not always available, and alternative methods are needed to provide reliable quantitative measurements of petroleum remediation efficiency. This study provides a detailed chemical characterization of lacustrine‐sourced crude oils and a technical basis for measuring the effectiveness of bioremediation efforts for soil impacted by those crudes. We show that the novel isoprenoid hydrocarbon botryococcane is relatively stable in lacustrine‐sourced crude oils compared with C3017α(H),21β(H)‐hopane under moderate biodegradation conditions generally observed in field samples. We have also demonstrated that, due to the stability and relatively elevated concentration of botryococcane in lacustrine oils, it can be reliably measured using the more cost‐effective and available GC/FID methodology, and thereby be used to monitor the progress of ongoing soil bioremediation activities at remote sites. 相似文献
966.
Beehive fences as a multidimensional conflict‐mitigation tool for farmers coexisting with elephants
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Lucy E. King Fredrick Lala Hesron Nzumu Emmanuel Mwambingu Iain Douglas‐Hamilton 《Conservation biology》2017,31(4):743-752
Increasing habitat fragmentation and human population growth in Africa has resulted in an escalation in human–elephant conflict between small‐scale farmers and free‐ranging African elephants (Loxodonta Africana). In 2012 Kenya Wildlife Service (KWS) implemented the national 10‐year Conservation and Management Strategy for the Elephant in Kenya, which includes an action aimed at testing whether beehive fences can be used to mitigate human–elephant conflict. From 2012 to 2015, we field‐tested the efficacy of beehive fences to protect 10 0.4‐ha farms next to Tsavo East National Park from elephants. We hung a series of beehives every 10 m around the boundary of each farm plot. The hives were linked with strong wire. After an initial pilot test with 2 farms, the remaining 8 of 10 beehive fences also contained 2‐dimensional dummy hives between real beehives to help reduce the cost of the fence. Each trial plot had a neighboring control plot of the same size within the same farm. Of the 131 beehives deployed 88% were occupied at least once during the 3.5‐year trial. Two hundred and fifty‐three elephants, predominantly 20–45 years old entered the community farming area, typically during the crop‐ ripening season. Eighty percent of the elephants that approached the trial farms were kept out of the areas protected by the beehive fences, and elephants that broke a fence were in smaller than average groups. Beehive fences not only kept large groups of elephants from invading the farmland plots but the farmers also benefited socially and financially from the sale of 228 kg of elephant‐friendly honey. As news of the success of the trial spread, a further 12 farmers requested to join the project, bringing the number of beehive fence protected farms to 22 and beehives to 297. This demonstrates positive adoption of beehive fences as a community mitigation tool. Understanding the response of elephants to the beehive fences, the seasonality of crop raiding and fence breaking, and the willingness of the community to engage with the mitigation method will help contribute to future management strategies for this high human–elephant conflict hotspot and other similar areas in Kenya. 相似文献
967.
Renzun Zhao John T. Novak C. Douglas Goldsmith 《Waste management (New York, N.Y.)》2013,33(5):1207-1214
To explore the feasible treatment alternatives for organic contaminant, especially organic arsenic species in the landfill gas (LFG) condensate, a variety of treatment approaches were examined and evaluated in this study. Biological degradation, conventional and advanced oxidation, and physical absorption showed limited effectiveness to convert the methylated arsenic to inorganic arsenic. Reverse osmosis (RO) was found to be able to remove the organic arsenic and meet the discharge limits. Maximum removal efficiency and cost level were summarized for all treatment approaches tested, which can be a reference for the organic arsenic treatment method selection under different circumstances. 相似文献
968.
Douglas Goudie 《Water, Air, & Soil Pollution: Focus》2009,9(5-6):469-484
Engineering is taking a lead role in sustainability implementation, despite problems linking institutional decision-makers with such things as water purification and cleansing wetlands. An emerging science may help speed an all-system approach to implementing sustainable urban planning. The many innovative approaches to engineering and planning will lead to cities and suburbs where water, urban travel, energy chains and food provision infrastructures are bound together by ESD values, flow-on principles and a workable process of sustainability achievement. JCU Townsville is developing such a process of Sustainability Implementation Planning (SIP) and Engineering, aspiring to become a tropics sustainability exemplar. This article reports on a 90-strong workshop: Paths to Sustainability held in August 2008, with strong regional leadership support. An integrated intellectual frame and ‘futures oriented’ blueprint is provided to achieve the myriad cultural, social, economic, energy, water, food, engineering and environmental needs to ‘go sustainable’ in an urban setting, where most of us live. The workshop results show SIP water management begins with local raindrops, local capture, local ground penetration, use and reuse, entering local nutrient flows to local urban food gardens and then used as a source to grow aquatic protein and fuel oils. Energy engineering becomes a local mix of renewables and innovative storage, appropriate building design, transport systems and industry; including embodied and life-cycle energy analysis and careful considerations in all built structure and use. Urban planning, people movement, housing location and travel mode will increasingly be judged by energy costs, as will food production. 相似文献
969.
Roy V. Rea Kenneth N. Child David P. Spata Douglas MacDonald 《Environmental management》2010,46(1):101-109
Plants cut at different times produce resprouts that vary in their nutritional value relative to when they are cut. To determine
how vegetation management in transportation (road and rail) corridors at different times of the year could influence browse
quality in the years following cutting, and how this could potentially influence encounters between herbivores and vehicles,
we undertook a 3-year study. In 2001, at a wildlife viewing area near Prince George, British Columbia, Canada, we established
a control area and treatment areas where shrubs and trees that are used as food by moose (Alces alces) were cut at the beginning of June, July, August, September, and October. In the fall, moose were most often observed browsing
the resprouts of plants cut in August (years 1 and 2 post-treatment) and September (year 3). Cumulative winter track counts
were highest in the uncut control area in the years following cutting. Spring pellet counts revealed that most pellets were
deposited in the uncut (years 1 and 2) and August-cut (year 3) areas during winter. With the exception of the first year after
cutting, browse removal by moose was highest for plants cut later in the growing season. Overall, our findings suggest that
following cutting, plants cut later in the year are selected more often by moose relative to those cut earlier. To reduce
browse use of corridor vegetation in areas where concerns for moose-vehicle collisions exist, we recommend that vegetation
maintenance activities be conducted in the early summer months of June and July. 相似文献
970.
Conservation and Biodiversity Monitoring in the Tropics: Realities, Priorities, and Distractions 总被引:5,自引:1,他引:4
Douglas Sheil 《Conservation biology》2001,15(4):1179-1182