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1.
Scenarios of major terrestrial ecosystems in China   总被引:2,自引:0,他引:2  
The spatial pattern and mean-center shift of major terrestrial ecosystems, termed Holdridge Life Zones (HLZ), during the periods from 1961 to 1990 (T1), from 2010 to 2039 (T2), from 2040 to 2069 (T3) and from 2070 to 2099 (T4) were analyzed by combining the zonal patterns of climatic change in China and the climatic change scenarios of HadCM2 and HadCM3. The results showed that nival area would decrease rapidly with temperature increase in the future. HadCM2 and HadCM3 predicted that the nival areas might disappear in 552 years and 204 years, respectively. Using both HadCM2 and HadCM3, the five HLZ types with the largest areal extent are nival zone, cool temperate moist forest, warm temperate moist forest, subtropical moist forest and boreal wet forest, which collectively account for more than 50% of China's land mass. Among these five HLZ types, nival zone, warm temperate moist forest and boreal wet forest would decrease continuously, whereas subtropical moist forest and cool temperate forest would increase continuously during the four periods. HLZ diversity and patch connectivity would increase continuously in the 21st century. The shift distances of mean centers of HLZ types simulated using HadCM3 were markedly greater than those simulated using HadCM2, in general. The results from both HadCM2 and HadCM3 showed that boreal wet forest, subtropical moist forest, tropical dry forest, warm temperate moist forest and subtropical wet forest had bigger shift ranges, indicating that these HLZ types are more sensitive to the climatic change scenarios of HadCM2 and HadCM3.  相似文献   
2.
基于县域污染物排放和人口社会经济数据库,运用熵权法构建水气污染综合指数测度广东省水气环境污染状况,在解析2012—2016年水气环境污染时空变化与主体功能区分异特征的基础上,采用空间计量模型考察水气环境污染的驱动因素及其在不同类型主体功能区之间的差异.研究结果表明:① 2012—2016年,广东省水气污染综合指数降幅达到46.93%,处于污染指数高值区间的县域数量大幅减少,并呈现由边缘向核心收缩的空间变化特征;② 4类主体功能区的水气环境污染均有明显改善,但相对而言,城市化地区和农产品主产区仍是广东省水气污染物排放的主要承压区;③人口规模是各类主体功能区水气环境污染的共性驱动因素,此外,城市化地区、农产品主产区和重点生态功能区还分别受到工业化水平、社会固定资产投资和财政收入分权程度的影响.建议从引导城乡居民绿色生活、持续提升清洁生产技术、增加地方财政分权激励机制中的环境效益考核入手强化区域环境污染综合治理.  相似文献   
3.
李璐  董捷  徐磊  张俊峰 《自然资源学报》2019,34(5):1003-1015
开展功能区土地利用碳收支评估并构建碳补偿分区优化框架,对于制定适应各功能区低碳策略、指导补偿额度流向、推动区域协调发展具有重要现实意义。以武汉城市圈县域为基本单元,在分析主体功能区划下土地利用碳收支空间分异特征的基础上,借助标准显示性比较优势指数法、SOM-K-means模型、二维关联矩阵等方法,对武汉城市圈进行了碳补偿类型区划分及优化。结果表明:武汉城市圈各县域土地利用碳排放总量地区差异显著,呈现“西高东低,中心最高”空间分布格局;主体功能区划下土地利用碳排放、碳吸收均具有明显空间分异特征,碳吸收与碳排放呈现出一定程度的相对空间分布趋势;武汉城市圈共有16个碳补偿支付区、11个碳补偿获补区以及12个碳补偿平衡区;结合主体功能区规划战略目标,最终形成7类碳补偿空间优化区,并对每一类型区提出了相应的低碳发展方向及策略。  相似文献   
4.
/ The management of lands adjacent to federally designated wilderness is increasingly seen to have the potential to negatively impact wilderness resources and management objectives. This paper first examines the numerous and often conflicting laws and regulations that influence how managers can mitigate transboundary issues. We then examine the various types of transboundary issues, and describe how they impact wilderness resources. Transboundary issues include recreational use, extractive activities, fire management, exotic species introductions, aircraft overflights and military operations, water diversion, urban encroachment, and transported pollutants. KEY WORDS: Adjacent lands; Buffer zones; Ecosystem management; Wilderness; Zones of influence  相似文献   
5.
钼矿区土壤中重金属污染状况的分析与评价   总被引:11,自引:0,他引:11  
曲蛟  袁星  王莉莉  王楠 《环境保护科学》2007,33(2):36-38,48
对葫芦岛钼矿区土壤重金属污染的情况进行了详细研究。选择土壤样本80个,采用HNO3-HF-HClO4混酸对土壤样品进行处理,运用等离子体发射光谱仪(ICP-OES)测定土壤样品中Pb、As、Hg、Cr、Cd、Zn、Cu、Ni、Mo的含量,全面系统地评价土壤重金属污染现状。结果表明,该矿区土壤重金属As、Cd和Hg污染较为严重,平均含量分别达154.13mg/kg,74.92mg/kg和3.06mg/kg。不同片区间存在明显差别,污染强度以矿山山沿污染最高,其次是运输区、选矿厂及矿区附近山地,内梅罗综合指数分别为78.34、74.34、71.42、68.55。  相似文献   
6.
环境政策是主体功能区区域政策的重要组成部分,从环境准入政策、环境管理政策和环境经济政策3个方面研究提出了不同主体功能区域的环境政策导向,以推动主体功能区分类别环境政策框架体系的形成。  相似文献   
7.
Marine-protected areas (MPAs) are vital to marine conservation, but their coverage and distribution is insufficient to address declines in global biodiversity and fisheries. In response, many countries have committed through the Aichi Target 11 of the Convention on Biological Diversity to conserve 10% of the marine environment through ecologically representative and equitably managed MPAs by 2020. The rush to fulfill this commitment has raised concerns on how increasing MPA coverage will affect other elements of Target 11, including representation and equity. We examined a Philippines case study to assess and compare 3 MPA planning approaches for biodiversity representation and equitable distribution of costs to small-scale fishers. In the opportunistic approach, MPAs were identified and supported by coastal communities. The donor-assisted approach used local knowledge to select MPAs through a national-scale and donor-assisted conservation project. The systematic conservation planning approach identified MPA locations with the spatial prioritization software Marxan with Zones to achieve biodiversity objectives with minimal costs to fishers. We collected spatial data on biodiversity and fisheries features and performed a gap analysis to evaluate MPAs derived from different approaches. We assessed representation based on the proportion of biodiversity features conserved in MPAs and distribution equity by the distribution of opportunity costs (fishing areas lost in MPAs) among fisher stakeholder groups. The opportunistic approach did not ineffectively represent biodiversity and resulted in inequitable costs to fishers. The donor-assisted approach affected fishers disproportionately but provided near-optimal regional representation. Only the systematic approach achieved all representation targets with minimal and equitable costs to fishers. Our results demonstrate the utility of systematic conservation planning to address key elements of Target 11 and highlight opportunities (e.g., integration of local and scientific knowledge can address representation and equity concerns) and pitfalls (e.g., insufficient stakeholder considerations can exacerbate social inequalities) for planning MPAs in similar contexts.  相似文献   
8.
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   
9.
A climatic classification for Europe suitable for pesticide fate modelling was constructed using a 3-stage process involving the identification of key climatic variables, the extraction of the dominant modes of spatial variability in those variables and the use of k-means clustering to identify regions with similar climates. The procedure identified 16 coherent zones that reflect the variability of climate across Europe whilst maintaining a manageable number of zones for subsequent modelling studies. An analysis of basic climatic parameters for each zone demonstrates the success of the scheme in identifying distinct climatic regions. Objective criteria were used to identify one representative 26-year daily meteorological series from a European dataset for each zone. The representativeness of each series was then verified against the zonal classifications. These new FOOTPRINT climate zones provide a state-of-the-art objective classification of European climate complete with representative daily data that are suitable for use in pesticide fate modelling.  相似文献   
10.
ABSTRACT

This paper investigates whether environmental regulation affects firm’s performance including productivity, wage and employment using firm-level data in 1996–2007. The identification uses Two Control Zones (TCZ) policy implemented by the Chinese government in 1998, in which tougher environmental regulations were imposed in TCZ cities but not others. By difference-in-differences estimation, we find that tougher environmental regulation leads to larger increase on both total factor productivity and wage, and firms tend to employ fewer workers under pressure of environmental protection. Heterogeneous tests show that the impacts are better for non-pollution intensive firms, non-exporters and SOEs. Finally, we find that R&D input and exiting firms among industry are the driving forces for enhancing TFP and increasing wage and unemployment.  相似文献   
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