首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 203 毫秒
1.
提出了评价对象、评价目标和评价方法三位一体的城镇生态承载力综合评价方法,构建了递阶多层生态承载力评价指标体系和面向应用对象的、融合多指标评语信息的生态承载力综合评价模型.以浙江省义乌市为例,对2000-2007年义乌市的生态承载力状况进行了评价与分析.结果表明,义乌市2000 2007年的生态承载力得分在60~70分,且呈逐年增加的趋势,说明其承载力状况良好;各支持力要素中,环境支持力得分一般,虽然随时间呈现一定波动但基本保持不变.资源支持力得分最差,人类支持力得分最高,且随时间逐年增加.结合研究区域实际情况对其生态承载力影响因素进行了剖析,并提出了生态承载力提高措施,为其可持续发展提供理论指导.  相似文献   

2.
资源环境承载力研究是生态文明建设的重要组成部分,已经上升到国家战略地位。地质环境承载力评价是资源环境承载力研究的重要内容之一,也是可持续发展研究的重要方向。结合山东半岛地质环境现状和特点,将山东半岛地质环境承载力指标体系划分为水文地质环境、工程地质环境和环境地质问题3类一级指标,每类一级指标各选择其典型二级指标(共12项)构建地质环境承载力评价体系,采用层次分析法(AHP)确定各个评价指标的权重,采用综合加权指数方法,借助地理信息系统(GIS)空间分析及数据属性库管理相结合的方法对现阶段山东半岛地质环境承载力进行了评价。评价结果将山东半岛地质环境承载力划分为4个等级,并对每个等级区域做了分析说明,以期为推进生态文明建设及可持续发展提供科学依据。  相似文献   

3.
在海洋经济快速增长的同时,由于海域污染造成的海洋生态环境破坏等问题,严重制约了海洋资源、生态和环境的可持续发展.结合国内外海洋资源、生态和环境承载力研究方法,将人口、社会经济、海洋资源、生态和环境系统服务功能纳入一个综合系统,将海洋生态系统服务功能引入到承载力评价指标体系和研究方法中,构建了以系统动力学(SD)模型、状态空间评价模型、多目标规划( MOP)模型为主,以海洋生态系统服务功能价值评估、灰色预测模型GM(1,1)和曲线回归模型等为辅助手段的海洋资源-生态-环境承载力复合系统(以下简称复合系统),并选取渤海湾进行实证研究.通过复合系统在渤海湾的应用,定量评价和预测渤海湾的承载状况,为海洋开发与管理以及区域协调发展提供评价和决策支持的技术方法,促进中国海洋资源、生态和环境的可持续利用及海洋经济的可持续发展.  相似文献   

4.
水环境污染与生态用水短缺是制约流域环境与经济社会可持续发展的关键因子,评估基于水量、水质和水生态约束的水生态承载力变化对支撑环境管理决策具有重要意义。以滇池流域为研究对象,构建了流域水生态承载力评价模型和驱动力模型,对流域1999年到2014年水生态承载力变化进行了评估,并识别了主要驱动力及其贡献。结果表明,滇池流域的水生态承载力以2009年为界发生突变,前期呈现稳定状态,主要原因是经济社会发展的促进效应与水污染的阻滞效应大致相当;随后呈现快速上升趋势,经济社会的持续增长与水环境改善是导致上升的主要原因。人口因子是水生态承载力的负向驱动力,经济增长因子为水生态承载力的正向驱动因子。控制流域的人口增长,提高经济增长水平对流域水生态承载力提升具有重要意义。  相似文献   

5.
经济的高速发展不只是为社会带来了便利,也无形中增加了水资源消耗的速率与水环境污染的负担。自“十三五”以来,为提高断面水环境质量、提升整体水质环境,各省市相继出台了水环境提升、水污染防治以及生态补偿政策。南京市江宁区顺应中央要求并结合自身特点,积极制定并实施了断面生态补偿工作方案,建立了由考核指标、补偿方式、核算方法、补偿标准组成的成套断面生态补偿考核系统。明确了补偿标准机制、补偿责任分配以及补偿资金使用等关键问题。为推进江宁区断面水质达标工作与水环境提升的总体目标奠定了夯实的基础。  相似文献   

6.
城市是社会发展的必然产物,也是人类经济和文化的中心,目前城市发展与生态环境保护的矛盾是中国突出的资源环境问题。在城市发展的过程中,建立全面反映城市化过程中生态环境综合状况的评价指标体系对城市可持续发展至关重要。对宁波中心城区2000、2005和2010年城市化强度、生态质量、环境质量、资源环境效率和生态胁迫等5个方面指标分析的基础上,进行了城市化生态环境综合评价。结果表明,2000—2010年宁波中心城区城市化生态环境综合评价得分从0.48降至0.29。宁波中心城区经历了高强度的城市化发展,资源环境效率大幅提升,但对生态环境造成了胁迫。发展过程中需要进一步优化经济和产能结构,坚持集中集约发展,并从总量控制和强度控制两个方面入手,强化主要污染源的控制。  相似文献   

7.
在已有相关研究的指标体系和国家颁布的相关指标体系基础上,提出了区域水生态承载力评价指标体系的构建依据、构建原则、分类框架、指标选取方法和标准确定方法。根据水生态承载力的概念和内涵,以压力-状态-响应(PSR)为指标体系分类框架,采用频数统计法和理论分析法相结合的方法,将已有研究中常用的、与水生态承载力密切相关的指标筛选出来,构建了区域水生态承载力指标体系,包括58个指标,其中核心指标19个,备选指标39个。在此基础上,参考国家颁布的相关标准,选取适当的核心指标对渭河陕西段水生态承载力进行评价,并进一步计算压力指数、状态指数、响应指数和承载指数,结果显示渭河陕西段水环境系统压力较大,状态最差,响应程度较高,水环境严重超载。  相似文献   

8.
生态城市建设作为解决城市的环境污染和生态破坏的重要途径,已经受到了政府、学者和广大群众的关注。南京是一个典型的资源消耗型城市,具有一定的代表性,因此就南京自2005年开始的生态城市建设状况进行了研究,对其他城市具有参考意义。首先,介绍了南京生态城市建设的必要性、总体定位、基本目标。接着,从南京的经济、社会、文化、自然条件出发,结合过去的实践经验,从生态农业和农村、生态工业园区、生态社区三个角度,分析了南京生态城市建设的现状,并对存在的问题进行了分析,同时还对《国家生态城市建设指标》和《南京生态建设规划纲要》中的经济发展、资源与环境、社会进步三大类28项指标进行了对比研究。最后,针对南京建设生态城市所存在的主要问题,结合南京的城市特点,对照南京生态城市建设的战略定位和量化指标,提出了相应的对策和措施。  相似文献   

9.
建设生态文明,以把握自然规律、尊重和维护自然为前提,以人与自然、环境与经济、人与社会和谐共生为宗旨,以资源环境承载力为基础,以建立可持续的产业结构、生产方式、消费模式以及增强可持续发展能力为着眼点,加快构  相似文献   

10.
福州市作为海西经济区的5大龙头城市之一,其海洋经济发展非常迅速,已经成为福州市经济发展的支柱,近岸海域环境质量也承受着巨大的压力。应用地理信息系统(GIS)对福州市近岸海域进行分区,并采用熵值法分析评估了福州市不同海域区块的环境承载力变化趋势。从环境承载力评价结果来看,福州市近岸海域环境承载力空间上呈现湾区河口环境承载力相对较弱的分布,这主要受入海河流污染物排放量、沿海地区城镇发展建设等因素的影响。同时,基于环境承载力的评估结果,对福州市近岸海域的发展建设以及环境保护工作提出了相应的措施和建议。  相似文献   

11.
A number of key projects in the Environmental Protection Agency (EPA) particulate R&;D program having applicability to industry are presented. For electrostatic precipitators (ESP) there is presented the result of work on large diameter discharge electrodes which provide a decrease in penetration of up to a factor of 4 when compared to conventional small diameter electrodes. Also discussed is the multistage ESP which provides a collection efficiency that would require a collecting plate area 4 or 5 times larger with conventional ESP technology. The E-SOX technology makes use of the multistage concept to free up space in the ESP for SO2 removals of up to 90%. Electrostatically augmented fabric filtration provides a reduction in pressure drop of about 5 0% as compared to conventional fabric filtration. Wind tunnel modeling of windbreaks for material storage piles indicates a potential for providing engineering design data that would allow significant emission reduction caused by wind erosion  相似文献   

12.
This paper investigates some of the reflectivity characteristics that clouds (when modelled as solid bodies) must exhibit to be compatible with observations that the reflecting surface of a cloud (i) appears almost equally bright across its face, (ii) is brightest when the cloud is opposite to the Sun but decreases in brightness as the cloud moves to other positions and (iii) increases in brightness with increasing optical thickness of the cloud in the observer's line of sight. These observations, respectively, are shown to imply that the peak value of the bidirectional total reflectivity from a cloud surface (i) increases in inverse proportion to the cosine of the angle between the Sun and the normal to the cloud surface, as the incident angle increases, (ii) appears to be directed back in the direction of the incident radiation, and (iii) increases as optical thickness of the cloud in the observer's line of sight increases. The results could have application in many fields (e.g. modelling diffuse radiance distributions for cloudy skies).  相似文献   

13.
Abstract

A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits.  相似文献   

14.
结合扬中生态环境的基本情况和存在的不足,进行了具体分析,对扬中未来生态建设的发展方向提出了建议及实施措施。  相似文献   

15.
16.
张仁泉 《污染防治技术》2005,18(2):15-17,34
在实施ISO/IEC17025:1999标准《检测和校准实验室能力的通用要求》过程中,通过实验室质量管理体系内部审核的实践与系统分析,识别出内部审核实施阶段的关键环节,提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法,对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。  相似文献   

17.
介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠  相似文献   

18.
The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing.  相似文献   

19.

Objective

This work aims to investigate the correlation between the photocatalytic activity determined by methylene blue bleaching (DIN 52980), stearic acid degradation, and degradation of acetone in gas phase.

Method

The photocatalytic TiO2 coatings included in this investigation ranged from thin commercially available coatings (ActivTM and BioCleanTM) and ready to use suspensions (Nano-X PK1245) to lab-produced PVD and sol?Cgel coatings. XRD analysis of the photocatalytic coatings showed that all the coatings consisted of nanocrystalline anatase, although the thickness and porosity varied considerably.

Results

The study showed that the reproducibility of the activity measurements was good. However, more importantly, the investigation showed that there is a good correlation between the activities determined by the different methods even though the characteristics of the photocatalytic coatings and the organic probe molecules varied considerably.

Conclusion

The overall findings of this work suggest that there is a good correlation between the investigated methods. These results are promising for the future work concerning standardization of methods for determination of the activity of photocatalytic films.  相似文献   

20.
Bhattacharya A  Sarkar SK 《Ambio》2003,32(1):70-75
India has a very extensive coastline of about 7515 km, rich in diverse living resources. These resources continue to deteriorate with rampant harvesting or are altered for other uses such as aquaculture and fisheries. The present paper deals with degrading coastal habitats in northeastern India, and projects the intensity of the stress arising from the collection of tiger prawn seeds (Penaeus monodon) for aquacultural farms and molluskan shells for poultry feed and edible lime. Indiscriminate exploitation of these resources leads to a heavy reduction of the species concerned and other associated marine communities. The magnitude of such destruction has been quantified. The impacts of biodiversity loss and their after-effects on the ecobalance of this coastal system have become a matter of great concern to ecologists to maintain security and sustainability. The authors propose a public awareness program on themes relating to the importance of biodiversity for human livelihoods.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号