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61.
62.
从农村土地整理的内涵及现实情境出发构建投入产出绩效评价指标体系,运用DEA方法对浙江省已竣工验收的48个国家投资土地整理项目效率水平进行测度,借此深入分析农村土地整理项目的治理绩效以及影响因素,旨在为改善我国农村土地整理项目治理绩效研究提供新的理论与方法。研究结果显示:(1)浙江省48个国家投资项目的综合效率均值为0.851、技术效率均值为0.903、规模效率均值为0.936,说明项目总体治理绩效较好,但项目之间的差异比较明显;(2)超效率分析发现,杭州北部、宁波南部和温州东南部等自然和社会条件较好地区的项目绩效水平较高,衢州西部和奉化西南等丘陵地区绩效水平较低;(3)影响因素分析发现,生态防护林种植数量、灌溉渠系长度、土地平整土方量、田间道路长度等工程投入过量,作物总产值增加量、单位面积涉及人口数、植被覆盖率等产出不足是导致绩效不高的主要原因;(4)DEA分析法是一种有效的治理绩效分析法,有助于从技术改进和规模调整角度来理解农村土地整理项目治理绩效内涵。根据结论,提出应该从生产技术上增强项目投入产出的转化能力,以改善绩效水平。 相似文献
63.
The Stream and Its Altered Valley: Integrating Landscape Ecology into Environmental Assessments of Agro-Ecosystems 总被引:2,自引:0,他引:2
Little is known about the importance of landscape and land cover to the implementation and performance of agricultural conservation projects designed to improve stream quality. In our study, we addressed the potential importance of landscape and land cover to conservation projects by measuring variation across 191 μ-basins (100–2400 ha) and integrating the observed variation into a study design aimed at determining the effectiveness of conservation projects. Our findings indicate that there are strong gradients across which landscape and land cover attributes vary. Land cover varied along a gradient of agricultural intensity, basin morphometry across gradients of stream closure and basin size, basin substrate was described by variation in drumlin formation, glacial landform type, and soil drainage, while agricultural conservation projects varied according to the level of project implementation. Correlation of these gradients found several associations between landscape and land cover, indicating that agricultural intensity was being constrained predominantly by drumlin formation and glacial landform type. Landscape and land cover did not appear to be determining factors in the implementation of conservation projects by land owners. Based on these findings we chose 32 μ-basins which represented the variability along each of the defined gradients for further study. We conclude that landscape scale variables demonstrate important variation and covariation that can and should be integrated into study designs for the assessment of streams and human activities affecting streams. 相似文献
64.
The Economic and Environmental Outcomes of Microfinance Projects: An Indian Case Study 总被引:1,自引:0,他引:1
Microfinance projects now seek to achieve improvement in environmental quality in addition to poverty alleviation. Achievement
of these goals may depend upon the economic and environmental impact of microfinance businesses. This study is a quantitative
analysis of these outcomes for Ecodevelopment, an Indian microfinance project, which aims to prevent forest degradation by
poverty alleviation. The study divides businesses into perishable goods, non-perishable goods, simple skills, and special
skills and measures their economic outcome by two indicators, repayment percentage and continuity of businesses. The study
examines the effect of loan amount on the economic outcome of businesses. To quantify the environmental outcome, it analyzes
the use of firewood or fodder and release of pollutants by businesses. The results show that loan amount does not affect the
economic outcome, special skills have best performance, and skills cause less pressure on forest resources. These results
suggest the need for development of knowledge-intensive skills, involvement of institutions in the operations of business,
and inclusive policies for protected area management. 相似文献
65.
通过对工程项目特点的分析和对参与项目建设当事人对工程质量安全的影响归因分析,认为,制度安排的缺陷及诚信文化缺失是我国建设工程质量安全事故频繁发生的根本原因。根据我国国情并借鉴国际工程保险的经验,笔者指出,专业保险公司介入建设工程项目监理,是弥补制度缺陷和诚信文化缺失、提高工程的质量安全系数的最佳选择。 相似文献
66.
ABSTRACT: The optimization of real-time operations for a single reservoir system is studied. The objective is to maximize the sum of hourly power generation over a period of one day subject to constraints of hourly power schedules, daily flow requirement for water supply and other purposes, and the limitations of the facilities. The problem has a nonlinear concave objective function with nonlinear concave and linear constraints. Nonlinear Duality Theorems and Lagrangian Procedures are applied to solve the problem where the minimization of the Lagrangian is carried out by a modified gradient projection technique along with an optimal stepsize determination routine. The dimension of the problem in terms of the number of variables and constraints is reduced by eliminating the 24 continuity equations with a special implicit routine. A numerical example is presented using data provided by the Bureau of Reclamation, Sacramento, California. 相似文献
67.
A conceptual model is developed herein for the purpose of stimulating discussions within groups planning and carrying out
integrated natural resource projects. We first describe four basic components of integrated planning and modeling efforts:
people, databases, technology, and organizational commitment. Second, we provide one view of the relationship between the
size of the project's decision-making body and the timing of decisions during a project's life cycle. Finally, these two discussions
are combined into a conceptual model describing the dynamic nature of decision-making within integrated projects. The abstractions
and generalizations described here are not unique to private industry or governmental organizations and should provide the
basis for a discussion of decision-making issues among interdisciplinary professionals embarking on large-scale or complex
modeling efforts. 相似文献
68.
Development of regional climate mitigation baseline for a dominant agro-ecological zone of Karnataka,India 总被引:1,自引:0,他引:1
P. Sudha D. Subhashree H. Khan G. T. Hedge I. K. Murthy V. Shreedhara N. H. Ravindranath 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):1051-1075
Setting a baseline for carbon stock changes in forest and land use sector mitigation projects is an essential step for assessing
additionality of the project. There are two approaches for setting baselines namely, project-specific and regional baseline.
This paper presents the methodology adopted for estimating the land available for mitigation, for developing a regional baseline,
transaction cost involved and a comparison of project-specific and regional baseline. The study showed that it is possible
to estimate the potential land and its suitability for afforestation and reforestation mitigation projects, using existing
maps and data, in the dry zone of Karnataka, southern India. The study adopted a three-step approach for developing a regional
baseline, namely: (i) identification of likely baseline options for land use, (ii) estimation of baseline rates of land-use
change, and (iii) quantification of baseline carbon profile over time. The analysis showed that carbon stock estimates made
for wastelands and fallow lands for project-specific as well as the regional baseline are comparable. The ratio of wasteland
Carbon stocks of a project to regional baseline is 1.02, and that of fallow lands in the project to regional baseline is 0.97.
The cost of conducting field studies for determination of regional baseline is about a quarter of the cost of developing a
project-specific baseline on a per hectare basis. The study has shown the reliability, feasibility and cost-effectiveness
of adopting regional baseline for forestry sector mitigation projects.
相似文献
N. H. RavindranathEmail: |
69.
摘要:水利工程建设项目为非污染生态破坏型建设项目,该类建设项目对水环境的影响按影响程度和影响类型可分为施工期影响和运行期影响,影响对象主要为水体、河流、及相关的生态环境等。本文对水利工程建设对水环境的影响进行分析,并提出了防范措施,为水利工程项目的设计、建设、后期的管理及环保措施的落实提供了依据。 相似文献
70.
蚁群算法是一种智能仿生优化算法,实际运用仿真模拟时具有良好的寻优性和高效性。将蚁群算法与石化项目的路径规划结合,借鉴蚁群算法解决旅行商问题TSP的思路并将之运用于应急路径规划,利用MATLAB仿真软件,以某石化项目的应急路径规划为实例,较好地实现了有关应急路径模拟图,可为有关石化项目的安全规划提供借鉴和参考。 相似文献