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961.
为了在水资源与水环境双重制约下制订人水和谐发展的政策提供决策支持,以我国中原经济区这一重点开发区域为例,基于层次分析法构建了以水系统自然条件、水系统服务功能及人类活动影响三要素(共计20项指标)为基础的流域水系统健康评价体系,并以2011年作为评价年,将中原经济区的水资源二级区作为基本流域单元对水系统健康状况进行评价. 结果表明:中原经济区9个水资源二级区中,除了淮河上游水资源二级区(3.20分,完全健康状态为5.00分)为基本健康状态、汉江水资源二级区(2.77分)和三门峡至花园口水资源二级区(2.18分)为亚健康状态以外,其余水资源二级区(0.55~1.77分)均为不健康及极不健康状态. 分析显示,人类活动影响是影响中原经济区内各流域水系统健康状况的主要原因,人口众多、工农业开发活动强度大使得其对水资源需求巨大. 部分水资源二级区对地下水资源依赖程度较高,造成不同程度的地下水超采现象. 伴随着高强度水资源利用的是水污染物的高强度排放,部分河流水污染状况严重,甚至在局部地区造成了地下水污染. 这种不健康的状态在中原经济区内由南向北随着水系统自然条件和水系统服务功能的降低呈加重趋势.   相似文献   
962.
为评价北京市城市河流地表水体中5种精神活性物质〔METH(甲基苯丙胺)、AMP(苯丙胺)、KET(氯胺酮)、EPH(麻黄碱)和HA(羟亚胺)〕的环境风险,通过对固相萃取柱(Oasis HLB、Oasis MCX、Oasis WAX和Oasis PRiME HLB)类型、水样酸化、洗脱剂类型及体积等条件的确定,建立了同时测定水环境中精神活性物质的固相萃取-液相色谱-质谱(SPE-LC-MS/MS)联用方法,并对北京市城市河流地表水体中5种精神活性物质的质量浓度水平进行了调查,采用RQ(风险熵)法进行了风险评价. 结果表明,在水样未酸化条件下,Oasis MCX柱对精神活性物质的回收率最高,使用含5%(V/V)氨水的甲醇作为洗脱液,5种精神活性物质的回收率可以达到81.8%~91.1%. 地表水水体基质加标结果表明,5种精神活性物质的加标回收率均大于75.5%,相对标准偏差均小于10.0%. 方法检出限为0.30~0.80 ng/L,定量限为1.00~2.68 ng/L. 北京市7条城市河流中5种精神活性物质的质量浓度在1.00~99.51 ng/L之间. EPH在所有采样点均被检出且质量浓度较高,ρ(EPH)平均值为22.79 ng/L;ρ(AMP)相对较低,在1.54~11.23 ng/L之间,但AMP检出率为97.06%;ρ(METH)较高,平均值为14.63 ng/L,最高值(99.51 ng/L)出现在坝河. 研究显示,北京市地表水中5种精神活性物质的RQ均小于0.1,表明其可能的环境风险较低,但由于精神活性物质本身具有生物活性,它们对城市河流水生生态系统产生的潜在危害不容忽视.   相似文献   
963.
东阳江是钱塘江源头之一,近年来,人口的增长、工业经济的发展以及城市化进程的加快,导致东阳江以及下游钱塘江的环境压力日趋严重.本文运用污染指数法对东阳江上中下游四个监测断面进行水质综合评价,并分析水环境问题的成因,从城镇生活污水治理、农村生活污水治理、河道综合整治与保护、环境监管提升四个方面提出相应的流域环境保护综合治理措施,以期为东阳江流域环境治理提供一定的科学支撑,以进一步减轻钱塘江环境压力.  相似文献   
964.
河流沉积物重金属污染状况对河流水生态系统健康发展具有重要意义.采集开封城市河流水系表层沉积物,分析了沉积物p H、粒度、有机质、总氮及6种重金属含量,使用相关性与主成分分析方法对沉积物中重金属来源进行解析,并采用污染负荷指数法和沉积物质量基准系数法进行了重金属的污染评价.结果表明,开封城市河流表层沉积物有机质平均含量为88.87 g·kg-1,全氮平均含量为2.48 g·kg-1,重金属Cd、Cr、Cu、Ni、Zn和Pb含量远超河南省土壤元素背景值.相关分析和主成分分析显示,沉积物有机质、全氮含量和重金属含量有一定相关关系,而沉积物p H及平均粒径对重金属含量影响较小;6种重金属可被辨识出2个主成分,其中Cd、Cr、Zn和Pb为人为复合源因子,Cu和Ni为工业与自然源因子.污染负荷指数分析表明,惠济河和化肥河为强度污染,黄汴河、东护城河、药厂河和马家河为中度污染.沉积物质量基准系数评价结果表明,惠济河存在中等生态风险,化肥河存在高等生态风险,且沉积物重金属存在较大潜在生物毒性效应.  相似文献   
965.
Saproxylic (dead-wood-associated) and old-growth species are among the most threatened species in European forest ecosystems, as they are susceptible to intensive forest management. Identifying areas with particular relevant features of biodiversity is of prime concern when developing species conservation and habitat restoration strategies and in optimizing resource investments. We present an approach to identify regional conservation and restoration priorities even if knowledge on species distribution is weak, such as for saproxylic and old-growth species in Switzerland. Habitat suitability maps were modeled for an expert-based selection of 55 focal species, using an ecological niche factor analyses (ENFA). All the maps were then overlaid, in order to identify potential species’ hotspots for different species groups of the 55 focal species (e.g., birds, fungi, red-listed species). We found that hotspots for various species groups did not correspond. Our results indicate that an approach based on “richness hotspots” may fail to conserve specific species groups. We hence recommend defining a biodiversity conservation strategy prior to implementing conservation/restoration efforts in specific regions. The conservation priority setting of the five biogeographical regions in Switzerland, however, did not differ when different hotspot definitions were applied. This observation emphasizes that the chosen method is robust. Since the ENFA needs only presence data, this species prediction method seems to be useful for any situation where the species distribution is poorly known and/or absence data are lacking. In order to identify priorities for either conservation or restoration efforts, we recommend a method based on presence data only, because absence data may reflect factors unrelated to species presence.  相似文献   
966.
This paper provides an overview of the emerging role of Aboriginal people in Sustainable Forest Management (SFM) in Canada over the past decade. The 1996 Royal Commission on Aboriginal Peoples (RCAP) provided guidance and recommendations for improving Aboriginal peoples' position in Canadian society, beginning with strengthening understanding and building relationships between Aboriginal and non-Aboriginal parties. This paper explores the extent to which advances in Aboriginal/non-Aboriginal relationships and Aboriginal forestry have been made as a result of RCAP's call for renewed relationships based on co-existence among nations. Such changes have begun to alter the context in which Aboriginal/non-Aboriginal relationships exist with respect to SFM. While governments themselves have generally not demonstrated the leadership called for by RCAP in taking up these challenges, industry and other partners are demonstrating some improvements. A degree of progress has been achieved in terms of lands and resources, particularly with co-management-type arrangements, but a fundamental re-structuring needed to reflect nation-to-nation relationships has not yet occurred. Other factors related to increasing Aboriginal participation in SFM, such as the recognition of Aboriginal and treaty rights, are also highlighted, along with suggestions for moving Aboriginal peoples' SFM agenda forward in the coming years.  相似文献   
967.
2009年初以来,在福建省九龙江北溪的支流和干流连续发生了拟多甲藻(Peridiniopsis penardii)水华。经检测,拟多甲藻水华没有明显的生物毒性,但其所形成的深褐色水色和轻微藻腥味对该流域的龙岩、漳州和厦门三城市的生产和生活是造成了一定的影响。研究结果表明,在甲藻水华的防治与应急处置过程中,必须进一步加强组织体系建设,明确各职能部门职责,并根据不同水域的实际情况和季节变化,采取相应的物理、化学和生物方法予以防治和应急处置。  相似文献   
968.
Unsustainable hunting outside protected areas is threatening tropical biodiversity worldwide and requires conservationists to engage increasingly in antipoaching activities. Following the example of ecocertified logging companies, we argue that other extractive industries managing large concessions should engage in antipoaching activities as part of their environmental management plans. Onshore hydrocarbon concessions should also adopt antipoaching protocols as a standard because they represent a biodiversity threat comparable to logging. We examined the spatiotemporal patterns of small‐ and large‐mammal poaching in an onshore oil concession in Gabon, Central Africa, with a Bayesian occupancy model based on signs of poaching collected from 2010 to 2015 on antipoaching patrols. Patrol locations were initially determined based on local intelligence and past patrol successes (adaptive management) and subsequently with a systematic sampling of the concession. We generated maps of poaching probability in the concession and determined the temporal trends of this threat over 5 years. The spatiotemporal patterns of large‐ and small‐mammal poaching differed throughout the concession, and likely these groups will need different management strategies. By elucidating the relationship between site‐specific sampling effort and detection probability, the Bayesian method allowed us to set goals for future antipoaching patrols. Our results indicate that a combination of systematic sampling and adaptive management data is necessary to infer spatiotemporal patterns with the statistical method we used. On the basis of our case study, we recommend hydrocarbon companies interested in implementing efficient antipoaching activities in their onshore concessions to lay the foundation of long‐needed industry standards by: adequately measuring antipoaching effort; mixing adaptive management and balanced sampling; setting goals for antipoaching effort; pairing patrols with large‐mammal monitoring; supporting antipoaching patrols across the landscape; restricting access to their concessions; performing random searches for bushmeat and mammal products at points of entry; controlling urban and agricultural expansion; supporting bushmeat alternatives; and supporting land‐use planning.  相似文献   
969.
Abstract: Informally gathered species lists are a potential source of data for conservation biology, but most remain unused because of questions of reliability and statistical issues. We applied two alternative analytical methods (contingency tests and occupancy modeling) to a 35‐year data set (1973–2007) to test hypotheses about local bird extinction. We compiled data from bird lists collected by expert amateurs and professional scientists in a 2‐km2 fragment of lowland tropical forest in coastal Ecuador. We tested the effects of the following on local extinction: trophic level, sociality, foraging specialization, light tolerance, geographical range area, and biogeographic source. First we assessed extinction on the basis of the number of years in which a species was not detected on the site and used contingency tests with each factor to compare the frequency of expected and observed extinction events among different species categories. Then we defined four multiyear periods that reflected different stages of deforestation and isolation of the study site and used occupancy modeling to test extinction hypotheses singly and in combination. Both types of analyses supported the biogeographic source hypothesis and the species‐range hypothesis as causes of extinction; however, occupancy modeling indicated the model incorporating all factors except foraging specialization best fit the data.  相似文献   
970.
发展旅游业是扩大就业的重要渠道。森林公园旅游业是中国森林旅游业的主体。本文首先概述了中国森林公园建设与发展状况,并基于林业统计年鉴数据,分析中国森林公园旅游业发展及直接就业效应,进而采用投入产出法对森林公园旅游业的间接就业效应进行了测算,最后总结全文并提出相关政策建议。研究结果表明:森林公园旅游业持续发展的就业效应可观。测算数据显示,2011-2020年森林公园旅游业的总体就业量为512.1万人,其中直接和间接就业量分别为238.5万人和273.6万人。  相似文献   
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