全文获取类型
收费全文 | 1538篇 |
免费 | 59篇 |
国内免费 | 77篇 |
专业分类
安全科学 | 99篇 |
废物处理 | 23篇 |
环保管理 | 438篇 |
综合类 | 536篇 |
基础理论 | 116篇 |
污染及防治 | 173篇 |
评价与监测 | 108篇 |
社会与环境 | 115篇 |
灾害及防治 | 66篇 |
出版年
2024年 | 8篇 |
2023年 | 28篇 |
2022年 | 35篇 |
2021年 | 46篇 |
2020年 | 69篇 |
2019年 | 31篇 |
2018年 | 23篇 |
2017年 | 55篇 |
2016年 | 71篇 |
2015年 | 43篇 |
2014年 | 61篇 |
2013年 | 62篇 |
2012年 | 67篇 |
2011年 | 137篇 |
2010年 | 50篇 |
2009年 | 85篇 |
2008年 | 108篇 |
2007年 | 77篇 |
2006年 | 68篇 |
2005年 | 47篇 |
2004年 | 49篇 |
2003年 | 41篇 |
2002年 | 40篇 |
2001年 | 36篇 |
2000年 | 38篇 |
1999年 | 42篇 |
1998年 | 36篇 |
1997年 | 30篇 |
1996年 | 23篇 |
1995年 | 28篇 |
1994年 | 25篇 |
1993年 | 12篇 |
1992年 | 15篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 6篇 |
1988年 | 7篇 |
1987年 | 7篇 |
1986年 | 15篇 |
1985年 | 10篇 |
1984年 | 8篇 |
1983年 | 6篇 |
1982年 | 7篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1977年 | 2篇 |
1973年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有1674条查询结果,搜索用时 15 毫秒
941.
生态规划和生态建设是协调经济发展和生态环境关系,创造人与环境相和谐的人工化环境的重要调控对策.本文研究了沈阳开发区生态规划与建设中的理论、方法,着重探讨了开发区经济、环境协调发展的途径.其主要是:①选择理想的协调发展优化方案.②发展集中供热和低能耗的高技术产业.③节约水资源,提高水循环利用率.④在生态学原理指导下进行生态管理. 相似文献
942.
重庆的环境空气质量和酸雨十年回顾 总被引:8,自引:0,他引:8
重庆是中国酸沉降的一个代表地区。本文对过去十年的空气质量和酸雨的时空分布,化学特征,污染来源,途径以及发展趋势进行了回顾与评价。重庆近年的空气质量没有随城市的发展而恶化,然而,酸雨影响的区域却在扩大。 相似文献
943.
944.
对环境管理中可运用的经济手段及其在国内外的应用作了简要综述、并据此对在我国制定有关环境保护经济手段的政策问题进行了初步探讨。按照经济合作与发展组织的研究,环境保护经济手段可以分为5类:收费;补贴;押金制;建立市场;鼓励金。在我国,制定有关经济手段的政策,需考虑4个因素:①污染者付费;②与管制手段的关系;③激励机制;④操作成本。 相似文献
945.
AHP法是规划决策管理的有效工具,本文通过在城市生态系统质量评价中AHP法的应用着重阐述了城市生态系统的层次结构分析和在多级递阶结构的基础上,经过判断矩阵的建立和运算,为城市生态系统质量评价中权重确定的科学化提供了定量的依据。 相似文献
946.
947.
This paper presents the main results of two studies of contrasting natural and man-induced conditions along the Pacific coast
of Baja California (Mexico), based on the assumption that ecological insight can be obtained from man-induced modifications
insofar as relevant activities are explicitly addressed as parts of the systems under study. The study is concerned with a
fragmented coastal succulent-sage scrub and showed that several patches of different size and age may harbor as many species
as non-fragmented areas, and that 83% of the original species assemblage persisted in the fragments, in which the invasion
by opportunistic exotic species may not progress beyond certain limits. The study of dune-backed and urban-backed beaches
showed a significantly greater abundance of the Snowy Plover (Charadrius alexandrinus) at the dune-backed beach, where a much more active back-shore feeding of adult birds and the only evidences of breeding
occurred. Both studies refer to landscape features of regional concern and its results may be used in conservation management.
The results on fragmented coastal succulentsage scrub may encourage alternative urban designs that keep patches of the original
landscape, thus meeting existing requirements of low density urban development for most of the coastal succulent-sage scrub
area. The evidence presented on the negative effects of dune destruction on the abundance, feeding and reproductive performance
of a threatened bird species has a bearing on the topic of biodiversity management. It may also contribute to the conservation
of the coastal dunes system. 相似文献
948.
Climis A. Davos 《Journal of Coastal Conservation》1999,5(2):171-180
Coastal management is a collective action. As such, it depends for its effective implementation on the cooperation of a multitude
of stakeholders, i.e. civic organizations, economic interest groups, environmental groups, governmental agencies, scientists
and other individuals. Where ‘effective implementation’ implies the achievement of targeted objectives within targeted time
horizons and ‘cooperation’ connotes that stakeholders elect to pursue cooperative strategies that may yield higher gains for
all stakeholders instead of competitive strategies that may maximize individual benefits. Thus, the fundamental challenge
of Coastal Zone Management (CZM) is to maximize the effectiveness of this management by maximizing and sustaining stakeholder
cooperation. I submit that sustainable cooperation can be maximized and nurtured for its voluntariness only by a process-oriented,
cooperative CZM. The alternative, outcome-oriented, normative CZM can force, directly or indirectly, cooperation but it cannot
sustain it. My purpose in this paper, is to highlight arguments supporting this view as well as the analytical challenges
of cooperative ICZM. Certain points are also viewed in the light of preliminary findings of a research project designed to
probe these challenges. 相似文献
949.
生态系统服务及其变化是多种因素驱动的复杂过程,了解生态系统服务之间的权衡与协同作用及其驱动因素,对于实现生态系统服务有效管理和人类福祉至关重要.以长江经济带为研究区域,分析了2000~2020年产水、土壤保持、碳固定和粮食供给这4项生态系统服务的时空变化特征,运用相关性分析和地理加权回归识别和量化了生态系统服务间的权衡与协同关系,在此基础上应用偏最小二乘结构方程模型探究自然与人类活动对生态系统服务的影响,再通过地理探测器分析生态系统服务关系变化的驱动机制.结果表明:①近20年来,碳固定服务年均值由946.14 t·km-2增至1 202.73 t·km-2,粮食供给均值则由32.73万元·km-2增至127.22万元·km-2;产水和土壤保持服务增加幅度较小.②整体上,碳固定与土壤保持、粮食供给与产水为协同关系,其他生态系统服务之间为权衡关系;生态系统服务间的关系在不同地区存在一定的差异.③地形和气候是生态系统服务及多对生态系统服务权衡与协同关系的重要驱动因素,其中结构方程模型结果表明,气候对产水为正向影响(S = 0.73),地形对粮食供给为负向影响(S = -0.57);地理探测器结果揭示,影响碳固定与产水在空间上关系的主要驱动因子为海拔(q = 0.38)和降水(q = 0.19).研究结果可为长江经济带生态系统服务可持续管理和实现该区域生态环境保护与社会经济的协同发展提供科学参考. 相似文献
950.
Ecological network determination of sectoral linkages, utility relations and structural characteristics on urban ecological economic system 总被引:1,自引:0,他引:1
Analyzing the structure and functioning of the urban system revealed ways to optimize its structure by adjusting the relationships among compartments, thereby demonstrating how ecological network analysis can be used in urban system research. Based on the account of the extended exergy utilization in the sector of urban socio-economic system, which is considered as the composition of extraction (Ex), conversion (Co), agriculture (Ag), industry (In), transportation (Tr), tertiary (Te) and households (Do) sectors, an urban ecological network model is constructed to gain insights into the economic processes oriented to sustainable urban development. Taking Beijing city as the case, the network accounting and related ecological evaluation of a practical urban economy are carried out in this study in the light of flux, efficiency, utility and structure analysis. The results showed that a large quantity of energy and resources have to be consumed to maintain the structure and function of a city. The thermodynamic efficiencies of individual sector in Beijing remain at a low level. The social system in Beijing is a highly competitive network, and there are 8 competitive relations and only two mutualistic ones. The Domestic and Agricultural sector are the major controlling factors of the system. Moreover, the assessment results of Beijing are compared with the other three socio-economic systems, Norway, UK and Italy, and the ecological network function and structure comparisons are correspondingly illuminated and discussed. The conclusions indicate that the exergy-based network analysis can be refined to become an integrative tool for evaluation, policy-making and regulation for urban socio-economic system management concerning structure and efficiency at urban levels. 相似文献