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101.
102.
ZOE JEWELL 《Conservation biology》2013,27(3):501-508
Monitoring free‐ranging animals in their natural habitat is a keystone of ecosystem conservation and increasingly important in the context of current rates of loss of biological diversity. Data collected from individuals of endangered species inform conservation policies. Conservation professionals assume that these data are reliable—that the animals from whom data are collected are representative of the species in their physiology, ecology, and behavior and of the populations from which they are drawn. In the last few decades, there has been an enthusiastic adoption of invasive techniques for gathering ecological and conservation data. Although these can provide impressive quantities of data, and apparent insights into animal ranges and distributions, there is increasing evidence that these techniques can result in animal welfare problems, through the wide‐ranging physiological effects of acute and chronic stress and through direct or indirect injuries or compromised movement. Much less commonly, however, do conservation scientists consider the issue of how these effects may alter the behavior of individuals to the extent that the data they collect could be unreliable. The emerging literature on the immediate and longer‐term effects of capture and handling indicate it can no longer be assumed that a wild animal's survival of the process implies the safety of the procedure, that the procedure is ethical, or the scientific validity of the resulting data. I argue that conservation professionals should routinely assess study populations for negative effects of their monitoring techniques and adopt noninvasive approaches for best outcomes not only for the animals, but also for conservation science. Efecto de la Técnica de Monitoreo en la Calidad de la Ciencia de la Conservación 相似文献
103.
Monitoring,imperfect detection,and risk optimization of a Tasmanian devil insurance population 下载免费PDF全文
Tracy M. Rout Christopher M. Baker Stewart Huxtable Brendan A. Wintle 《Conservation biology》2018,32(2):267-275
Most species are imperfectly detected during biological surveys, which creates uncertainty around their abundance or presence at a given location. Decision makers managing threatened or pest species are regularly faced with this uncertainty. Wildlife diseases can drive species to extinction; thus, managing species with disease is an important part of conservation. Devil facial tumor disease (DFTD) is one such disease that led to the listing of the Tasmanian devil (Sarcophilus harrisii) as endangered. Managers aim to maintain devils in the wild by establishing disease‐free insurance populations at isolated sites. Often a resident DFTD‐affected population must first be removed. In a successful collaboration between decision scientists and wildlife managers, we used an accessible population model to inform monitoring decisions and facilitate the establishment of an insurance population of devils on Forestier Peninsula. We used a Bayesian catch‐effort model to estimate population size of a diseased population from removal and camera trap data. We also analyzed the costs and benefits of declaring the area disease‐free prior to reintroduction and establishment of a healthy insurance population. After the monitoring session in May–June 2015, the probability that all devils had been successfully removed was close to 1, even when we accounted for a possible introduction of a devil to the site. Given this high probability and the baseline cost of declaring population absence prematurely, we found it was not cost‐effective to carry out any additional monitoring before introducing the insurance population. Considering these results within the broader context of Tasmanian devil management, managers ultimately decided to implement an additional monitoring session before the introduction. This was a conservative decision that accounted for uncertainty in model estimates and for the broader nonmonetary costs of mistakenly declaring the area disease‐free. 相似文献
104.
Lobpreis T Vrana B Dominiak E Dercová K Mills GA Greenwood R 《Environmental pollution (Barking, Essex : 1987)》2008,153(3):706-710
Passive sampling of pollutants in water has been gaining acceptance for environmental monitoring. Previously, an integrative passive sampler (the Chemcatcher) was developed and calibrated for the measurement of time weighted average concentrations of hydrophobic pollutants in water. Effects of physicochemical properties and environmental variables (water temperature and turbulence) on kinetic and thermodynamic parameters characterising the exchange of analytes between the sampler and water have been published. In this study, the effect of modification in sampler housing geometry on these calibration parameters was studied. The results obtained for polycyclic aromatic hydrocarbons show that reducing the depth of the cavity in the sampler body geometry increased the exchange kinetics by approximately twofold, whilst having no effect on the correlation between the uptake and offload kinetics of analytes. The use of performance reference compounds thus avoids the need for extensive re-calibration when the sampler body geometry is modified. 相似文献
105.
Regional ecosystem monitoring is a central form of knowledge sharing and collaboration amongst scientists and decision makers on environmental health, land use change, and science-policy development. Despite the proliferation of such research networks on long-term monitoring on many continents, little has been achieved in Africa. This study aims to assess and examine the spatiotemporal trend and categorical patterns in ecosystem monitoring-related research in Africa for the benefits of conserving biodiversity and sustaining natural resource sectors for well-being and livelihood security, environmental planning, and ecological stewardship. A systematic review was conducted using bibliometric tools. Based on a set of search terms and peer-reviewed publications retrieved from various ecosystem monitoring networks and journal databases, further analysis was conducted using social network approaches, mapping tools, and content analysis. About 1442 scientific publications on ecosystem monitoring and related research were documented from 1987 to 2014 mostly published in English. The number of publication increased progressively since 1992 after the Convention on Biodiversity was signed and this trend peaked till 2008. South African Journal of Science was the most leading journal and Nature the most cited. Internationally coauthored and collaborative articles represented majority of the findings with the United Kingdom at the central position in the research network due to colonial relationships. Regional collaboration amongst countries is limited owing to language barriers and other institutional constraints such as funding and short-term projects. These findings have implication for prioritizing national and regional policies toward biodiversity science and its contribution to human well-being, food security, and global change responses. 相似文献
106.
107.
为独立评估环境空气连续自动监测系统运维质量,掌握环境空气监测数据准确性等信息,我国开展了环境空气连续自动监测系统性能审核工作,通过分析影响审核结果的相关因素,提出,性能审核标准气体浓度应接近实际监测空气中的气体浓度,性能审核时间的选择应满足《环境空气质量标准》(GB 3095—2012)中数据统计的有效性规定,性能审核气体压力应保持恒定并接近实际采样时的气压,标准气体进样方式应通过日常采样管路等,从而进一步提高性能审核结果的科学性和准确性,为生态环境管理部门了解环境空气数据质量提供坚实基础。 相似文献
108.
采用不同质量浓度的氨氮标准样品和实际样品,用氨气敏电极法和纳氏试剂分光光度法进行同步测试。结果表明,2种分析方法在水样氨氮质量浓度在0. 159~2. 81 mg/L范围内具有良好的可比性、精密性和准确性。氨气敏电极法的检出限为0. 03 mg/L,平行6次测定样品的相对标准偏差为0. 4%~4. 2%,加标回收率为85. 0%~110%;纳氏试剂分光光度法的检出限为0. 025 mg/L,平行6次测定样品的相对标准偏差为0. 5%~6. 4%,加标回收率为93. 0%~99. 8%。同时氨气敏电极法在样品预处理、试剂配制和分析时间上要优于纳氏试剂分光光度法。氨气敏电极法能够满足地表水自动监测在线比对实际工作的需求,该方法具有良好的适用性。 相似文献
109.
基于2011—2015年Landsat7、Landsat8等卫星遥感影像,结合土壤侵蚀面积、水资源量、降雨量、污染物排放量等统计数据,按照《生态环境状况评价技术规范》(HJ 192—2015),研究评价广东省"十二五"期间生态环境状况及其时空变化趋势,并对其影响因素进行综合分析。结果表明,广东省的生态环境状况总体为优,各市生态环境状况均属优、良,粤北生态环境状况整体最好;广东省及各市生态环境状况稳中趋好,但呈现温和地波动变化;主要污染物排放量下降和水资源总量提高是促进生态环境状况改善的主要原因。 相似文献
110.
介绍了采用称量法制备瓶装1μmol/mol氮气中42个组分挥发性有机物(VOCs)标准物质的研制方法。建立了选择离子模式,气相色谱-质谱联用的分析方法,对目标组分在气瓶中的长期稳定性进行了考察。所选择的42种目标组分完全满足中国环境保护标准《环境空气挥发性有机物的测定吸附管采样-热脱附/气相色谱-质谱法》(HJ 644—2013)和美国环保署《使用特殊处理的采样罐/气相色谱仪检测环境大气中的挥发性有机物》(EPA TO—14A)这2个方法标准中所规定的环境空气中挥发性有机有害成分的监测要求。将研制的气体标准物质与中国计量科学研究院(NIM)和英国国家物理实验室(NPL)分别进行了比对测试,取得了良好的比对结果与国际等效度。结果表明,1μmol/mol氮气中42种组分VOCs标准物质的有效期为一年,相对扩展不确定度为5.0%(包含因子k=2),并取得国家标准物质证书GBW(E)062231。 相似文献