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991.
992.
ANA NUNO NILS BUNNEFELD LOIRUCK C. NAIMAN E. J. MILNER‐GULLAND 《Conservation biology》2013,27(6):1355-1365
Assessing anthropogenic effects on biological diversity, identifying drivers of human behavior, and motivating behavioral change are at the core of effective conservation. Yet knowledge of people's behaviors is often limited because the true extent of natural resource exploitation is difficult to ascertain, particularly if it is illegal. To obtain estimates of rule‐breaking behavior, a technique has been developed with which to ask sensitive questions. We used this technique, unmatched‐count technique (UCT), to provide estimates of bushmeat poaching, to determine motivation and seasonal and spatial distribution of poaching, and to characterize poaching households in the Serengeti. We also assessed the potential for survey biases on the basis of respondent perceptions of understanding, anonymity, and discomfort. Eighteen percent of households admitted to being involved in hunting. Illegal bushmeat hunting was more likely in households with seasonal or full‐time employment, lower household size, and longer household residence in the village. The majority of respondents found the UCT questions easy to understand and were comfortable answering them. Our results suggest poaching remains widespread in the Serengeti and current alternative sources of income may not be sufficiently attractive to compete with the opportunities provided by hunting. We demonstrate that the UCT is well suited to investigating noncompliance in conservation because it reduces evasive responses, resulting in more accurate estimates, and is technically simple to apply. We suggest that the UCT could be more widely used, with the trade‐off being the increased complexity of data analyses and requirement for large sample sizes. Una Aproximación Novedosa para Evaluar la Prevalencia y Factores de la Cacería Ilegal en el Serengueti 相似文献
993.
994.
M. Yu. Semenov T. V. Khodzher V. A. Obolkin V. M. Domysheva L. P. Golobokova N. A. Kobeleva O. G. Netsvetaeva V. L. Potemkin R. Van Grieken N. Fukuzaki 《Chemistry and Ecology》2006,22(1):1-11
Data from 3-year-long observations on the chemical composition of precipitation, atmospheric gases, aerosols, soils, and surface waters at three monitoring stations in the Baikal region are presented. The stability of terrestrial ecosystems and surface waters to acidification has been estimated quantitatively. It has been shown that, unlike soils, surface waters of the Baikal watershed are more sensitive to acid deposition. The permissible acidity load for soils and surface waters of the territory varied from 0.30 to 20.00 keq ha-1 yr-1, whereas the maximal contemporary acidity load attains 0.50 keq ha-1 yr-1. 相似文献
995.
The inorganic anion pollution of the New Calabar River surface water was investigated. Results showed seasonal variations
in the inorganic anion levels. Water parameters such as sulfite, nitrate, phosphate, and alkalinity showed significantly higher
values in the rainy season than in the dry season. Dissolved oxygen, pH, sulfide, sulfate, ammonia, and nitrite showed no
significant differences between their rainy and dry season levels. Upstream-downstream changes were shown by conductivity,
total dissolved solids, chloride, salinity, and temperature. Exceptions occurred in the nitrite levels, where the effect was
minimal. Although the concentrations of some anions analyzed fell within internationally acceptable limits, the New Calabar
River water is, in the main, polluted with inorganic anions and may be unacceptable for potable and industrial uses without
treatment. 相似文献
996.
Global sustainability policies, such as the Sustainable Development Goals (SDGs) or the Aichi Targets, aim to ensure sustainable development, including improved human well-being and the conservation of nature. Although not yet explicitly used to evaluate the progress towards sustainable development, the ecosystem service concept implies a direct link between biodiversity and human well-being. This study explores how and which ecosystem services are currently considered in the SDGs and the Aichi Targets. We also identify which information might be already available for monitoring the progress towards their goals by reviewing national ecosystem assessments. This allows the identification of the main knowledge gaps for monitoring progress towards these global sustainability targets.There is a wealth of information on all major ecosystem services categories which is directly relevant for the Aichi Targets and the SDGs. The top 25% most cited ecosystem services across both policy documents are: Natural heritage and diversity, Capture fisheries, Aquaculture, Water purification, Crops, Cultural heritage & diversity and Livestock. Most monitoring information recommended for the global sustainability goals, as well as in the information available from national assessments, is biased towards supply related aspects of ecosystem services flows. In contrast, there is much less information on social behaviour, use, demand and governance measures. Indicators are rarely available for all aspects of a specific ecosystem service.The national statistical bureaus currently in charge of providing observations for reporting on SDGs, could be well placed to address this bias, by integrating ecological observations with socio-economic statistics into socio-ecological indicators for ecosystem services flows. IPBES can potentially address the gaps identified in this paper by improving coverage of the different dimensions of ecosystem services flows. 相似文献
997.
Simplified method for wetland habitat assessment 总被引:2,自引:0,他引:2
This article presents a wetland habitat assessment technique (HAT) using birds as indicators of habitat quality. The technique is quick, simple, inexpensive, and lends itself to screening large numbers of wetlands. HAT can provide input to more extensive evaluation techniques. Measures of species diversity and rarity are used to assess the quality of the wetland. By applying the notion of ecologically optimum size, the technique addresses the issue of economic efficiency. Results of field testing HAT on 11 tidally influenced wetlands are presented to illustrate HAT's utility. Application of HAT in a variety of situations is discussed. 相似文献
998.
盐碱地不同土地利用方式下土壤细菌群落结构多样性差异分析 总被引:7,自引:1,他引:6
为了研究盐碱地不同土地利用方式下土壤细菌群落结构特征分布,利用高通量测序技术,对黄河三角洲地区的耕地、园地和荒地中3个不同深度的土壤细菌群落结构多样性进行了研究.结果表明:①荒地中的土壤细菌群落丰富度和多样性均大于其他土地利用类型.②相同土地利用类型的细菌群落结构相似度较高,而不同土地利用类型的细菌群落结构有一定的差别.③细菌群落在门类水平上达到20门以上,优势菌种均以放线菌门、变形菌门、酸杆菌门、绿弯菌门及浮霉菌门为主,相对丰度约为69%~83%;属类水平的细菌群落达230多属,酸杆菌属在土壤中的相对丰度最高,为5.76%.④土壤有效磷、速效钾和有机质含量与土壤细菌多样性指数呈显著相关性. 相似文献
999.
1000.
对县级环境监测站标准化建设的思考 总被引:1,自引:0,他引:1
周希勤 《环境监测管理与技术》1997,9(3):28-29
分析了县级环境测站在标准化创建工作中存在的问题和实际困难。为加快标准化环境监测站的建设速度,促进环境测站的全面建设,提出了包括提高认识,制订目标,加强队伍建设和拓宽经费渠道的若干对策建议。 相似文献