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951.
塔里木石油资源的开发极大地促进了南疆地区社会和经济的发展。但同时也对开发区自然环境造成了一定的影响。深入全面地分析这些影响,制定预防措施,防止由此而引起的生态环境的进一步恶化,这对保障国民经济高速、持续、稳定发展,有着十分重要的意义。 相似文献
952.
简述了《江苏省生态环境监测条例》(以下简称《条例》)出台的重要意义,对《条例》的主要内容和特点进行了解读。《条例》于2020年5月1日正式实施,是我国首部生态环境监测地方性法规,也是落实党中央、国务院深化生态环境监测体制改革的具体举措,弥补了生态环境监测立法的空白。《条例》共分6章47条,重点建立了生态环境监测质量管理、监测机构监督管理、网络管理、污染源监测、监测信息公开与共享等制度,明确了统一监督管理、严厉打击监测数据造假等内容。提出,加快补齐监测网络建设、基层监测能力、污染源执法监测、社会监测机构监管等方面的短板,确保监测数据的真实准确,推动监测事业依法、科学、规范开展。 相似文献
953.
景观生态学与荒漠生态环境监测 总被引:2,自引:0,他引:2
通过对景观生态的阐述,在讨论荒漠生态环境监测的概念、对象、内容、方法和目的的基础上,分析了景观生态学成为荒漠生态环境监测理论和实践的基础的可能性和必要性,指出景观生态学在荒漠生态环境监测中的应用大有可为。 相似文献
954.
It is widely acknowledged that a simplified and robust approach to evaluating thecombined effects of chemical mixtures is critical for ecological risk assessment (ERA) of contaminated soil. The earthworm (Eisenia fetida) was used as a model to study the combined effects of polymetallic contamination and the herbicide siduron in field soil using a microcosm experiment. The responses of multiple biomarkers, including the activities of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and acetylcholine esterase (AChE), the concentrations of glycogen, soluble protein (SP), malonaldehyde (MDA), and metallothionein (MT), and the neutral red uptake test (NRU), were investigated. Multivariate analysis, Principal Component Analysis (PCA) and Spearman's Rank Correlations analysis (BVSTEP) revealed that the activities of AChE and CAT and the NRU content were the prognostic biomarkers capturing the minimum data set of all the variables. Internal Cd (tissue Cd) in earthworms was closely related to the health status of worms under combined contamination of heavy metals and siduron. The integrated effect (Emix) calculated based on the activities of AChE and CAT and NRU content using the stress index method had significantly linear regression with internal Cd (p<0.01). Emix(10), Emix(20), and Emix(50) were then calculated, at 1.27, 1.63 and 2.71 mg/kg dry weight, respectively. It could be concluded that a bioassay-based approach incorporating multivariate analysis and internal dose was pragmatic and applicable to evaluating combined effects of chemical mixtures in soils under the guidance of the top-down evaluation concept of combined toxicity. 相似文献
955.
环境效率是考量生态补偿政策实施效果的重要指标,对国家重点生态功能区生态补偿环境效率进行有效测度可以为完善我国生态补偿政策提供有益参考.采用三阶段DEA模型对长江经济带11个省市的国家重点生态功能区生态补偿环境效率水平、变化趋势及其差异性进行评价,通过线性数据转化方法对非期望环境负产出进行处理,并识别第三产业增加值占比等背景变量对投入产出效率的影响.结果表明:①长江经济带第三产业增加值占比对能源投入产出的影响显著(t值检验达到5%显著性水平),进出口总额、人均GDP、人口密度等因素对各项投入产出的影响均不显著.②长江经济带11个省市2012-2017年综合技术效率均值在剔除背景因素和随机干扰前后未发生变化,但纯技术效率均值由调整前的0.94升至调整后的0.96,规模效率均值由调整前的0.94降至0.92,表明纯技术效率对提高环境效率起主导作用.③上游4个省市(重庆市、四川省、云南省、贵州省)与中下游7个省市(江西省、湖南省、湖北省、安徽省、江苏省、浙江省、上海市)生态补偿环境效率均值差距较大,其中,云南省的环境效率最低.研究显示,长江经济带11个省市的国家重点生态功能区生态补偿环境效率从上游到下游整体呈上升趋势,应在提高综合技术效率的同时,更加注重基本公共服务能力和生态环境保护双重目标的协调. 相似文献
956.
中央生态环境保护督察是党中央、国务院推进生态文明建设和生态环境保护工作的重大制度创新。《中央生态环境保护督察工作规定》于近期正式出台,首次以党内法规形式明确了生态环境保护督察的制度框架、程序规范、权限责任等。从发展历程来看,我国生态环境保护督察大致经历了督企为主、督政督企并举、党政同责三个阶段。生态环境保护督察具有突出政治站位、压实责任,坚持问题导向、强化震慑,突出边督边改、取信于民等基本特征。为强化成果应用,全面准确把握当前我国生态环境保护工作的重点难点,本文设置7个一级指标和18个二级指标对首轮中央生态环境保护督察所指问题的分布特征进行统计分析,初步剖析问题产生原因,并从督察对象、督察内容和督察体制方面对第二轮中央生态环境保护督察进行了展望。 相似文献
957.
本文根据秦皇岛市的地理条件,气候资源和土壤资源,分析了该地区的农业生产总环境和自然经济条件,提出了因地制宜,合理利用各地的自然资源,建立科学合理又相近相趋的生态农业模式和实施方案。 相似文献
958.
Wetlands are critical natural resources in developing countries where they perform a range of environmental functions and provide numerous socio-economic benefits to local communities and a wider population. In recent years, however, many wetlands throughout eastern Africa have come under extreme pressure as government policies, socio-economic change and population pressure have stimulated a need for more agriculturally productive land. Although wetland drainage and cultivation can make a key contribution to food and livelihood security in the short term, in the long term there are concerns over the sustainability of this utilization and the maintenance of wetland benefits. This article draws upon recent research carried out in western Ethiopia, which addressed the sustainability of wetland agriculture in an area of increasing food insecurity and population pressure. It discusses the impacts of drainage and cultivation on wetland hydrology and draws attention to local wetland management strategies, particularly those characterized by multiple use of wetlands, where agriculture exists alongside other wetland uses. The article suggests that where multiple wetland uses exist, a range of benefits can be sustained with little evidence of environmental degradation. Ways of promoting and empowering such sustainable wetland management systems are discussed in the context of the wider need for water security throughout the region. 相似文献
959.
/ Many of the aquatic and terrestrial ecosystems of the Pacific Northwest United States have been simplified and degraded in part through past land-management activities. Recent listings of fishes under the Endangered Species Act and major new initiatives for the restoration of forest health have precipitated contentious debate among managers and conservation interests in the region. Because aggressive management activities proposed for forest restoration may directly affect watershed processes and functions, the goals of aquatic and terrestrial conservation and restoration are generally viewed as in conflict. The inextricable links in ecological processes and functions, however, suggest the two perspectives should really represent elements of the same problem; that of conserving and restoring more functional landscapes. We used recent information on the status and distribution of forest and fish communities to classify river subbasins across the region and explore the potential conflict and opportunity for a more integrated view of management. Our classification indicated that there are often common trends in terrestrial and aquatic communities that highlight areas of potential convergence in management goals. Regions where patterns diverge may emphasize the need for particular care and investment in detailed risk analyses. Our spatially explicit classification of subbasin conditions provides a mechanism for progress in three areas that we think is necessary for a more integrated approach to management: (1) communication among disciplines; (2) effective prioritization of limited conservation and restoration resources; and (3) a framework for experimentation and demonstration of commitment and untested restoration techniques. 相似文献
960.
Resource inventory and monitoring (I&M) programs in national parks combine multiple objectives in order to create a plan of
action over a finite time horizon. Because all program activities are constrained by time and money, it is critical to plan
I&M activities that make the best use of available agency resources. However, multiple objectives complicate a relatively
straightforward allocation process. The analytic hierarchy process (AHP) offers a structure for multiobjective decision making
so that decision-makers’ preferences can be formally incorporated in seeking potential solutions. Within the AHP, inventory
and monitoring program objectives and decision criteria are organized into a hierarchy. Pairwise comparisons among decision
elements at any level of the hierarchy provide a ratio scale ranking of those elements. The resulting priority values for
all projects are used as each project’s contribution to the value of an overall I&M program. These priorities, along with
budget and personnel constraints, are formulated as a zero/one integer programming problem that can be solved to select those
projects that produce the best program. An extensive example illustrates how this approach is being applied to I&M projects
in national parks in the Pacific Northwest region of the United States. The proposed planning process provides an analytical
framework for multicriteria decisionmaking that is rational, consistent, explicit, and defensible. 相似文献