首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   25387篇
  免费   1602篇
  国内免费   2357篇
安全科学   3842篇
废物处理   326篇
环保管理   5691篇
综合类   10658篇
基础理论   2714篇
环境理论   25篇
污染及防治   1108篇
评价与监测   1166篇
社会与环境   2508篇
灾害及防治   1308篇
  2024年   45篇
  2023年   251篇
  2022年   438篇
  2021年   610篇
  2020年   663篇
  2019年   572篇
  2018年   523篇
  2017年   685篇
  2016年   861篇
  2015年   850篇
  2014年   960篇
  2013年   1436篇
  2012年   1525篇
  2011年   1786篇
  2010年   1280篇
  2009年   1382篇
  2008年   1101篇
  2007年   1639篇
  2006年   1666篇
  2005年   1357篇
  2004年   1248篇
  2003年   1257篇
  2002年   1090篇
  2001年   935篇
  2000年   894篇
  1999年   807篇
  1998年   585篇
  1997年   482篇
  1996年   382篇
  1995年   358篇
  1994年   293篇
  1993年   261篇
  1992年   204篇
  1991年   160篇
  1990年   110篇
  1989年   72篇
  1988年   74篇
  1987年   52篇
  1986年   45篇
  1985年   51篇
  1984年   41篇
  1983年   34篇
  1982年   33篇
  1981年   26篇
  1980年   31篇
  1979年   42篇
  1978年   24篇
  1977年   20篇
  1973年   21篇
  1971年   19篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
61.
From an economic point of view, the industrial economy is efficient to overcome situations of a scarcity of goods. From a technological point of view, the resource efficiency of the manufacturing processes of the industrial economy has been permanently improved during the last 200 years. In addition, cleaner processes have been developed. However, from an ecologic point of view, an increasing world population with increasing consumption has produced a "global footprint" which approaches the carrying capacity of the planet. A circular economy and its high-value spin-offs-a lake economy and a performance or functional service economy-can fulfil customers' needs with considerably less resource consumption, less environmental impairment in production and considerably less end-of-life product waste, especially in situations of affluence, when a considerable stock of physical goods and infrastructures exists. Also, in situations of a scarcity of natural resources, both energy and materials, often characterised by rapidly rising resource prices, the economic actors of a circular economy have a high competitive advantage over the actors of the industrial economy, due to much lower procurement costs for materials and energy. From a social point of view, a circular economy increases the number of skilled jobs in regional enterprises. However, the shift from a linear manufacturing economy to a circular or service economy means a change in economic thinking from flow (throughput) management to stock (asset) management: in a manufacturing economy with largely unsaturated markets, total wealth increases through accumulation as resource throughput (flow) is transformed into a higher stock of goods of better quality (but in a manufacturing economy with largely saturated markets, wealth represented by the stock of goods will no longer increase); in a circular or service economy, total wealth increases through a smart management of existing physical assets (stock) that are adapted to changes in both technology and customer demand. This second approach not only applies to physical capital but equally to social capital, such as health and education and green GDP. To measure the social wealth of a population, it is not the amount of money spent on schools and hospitals that matters, butif this expenditure has led to a better education of the students, and a better health of the people.  相似文献   
62.
浙江木材产业可持续发展分析   总被引:1,自引:0,他引:1  
浙江是一个森林资源稀缺的区域,在面临森林资源稀缺的条件下,浙江木材产业发展却位居全国前列.论文首先从产业规模、产业组织和产业集聚三方面总续了浙江木材产业发展现状及特点;在此基础上,总结了浙江木材产业快速发展过程中面临的主要问题,诸如木材资源供给的不可持续性、木材产业经营成本不断上涨、国际市场与国内市场分割等.问题分析表明,木材资源的短缺已成为浙江木材产业发展的瓶颈,经营成本的上涨影响了浙江木材产业发展的动力,国内外市场分割限制了浙江木材产业的竞争范围,这直接影响到浙江木材产业的可持续发展.现代市场经济发展表明,产业可持续发展需要企业、行业协会以及政府的通力合作.最后,论文分别从企业、行业协会和政府三个层面提出了促进浙江木材产业可持续发展的对策建议.  相似文献   
63.
The implementation of sustainable development may seem a simple concept when written on paper. However to carry-out long term actions put forward by the Agenda 21 (AG21) at the local level represents one of the main challenges as municipal governments in general do not have the capacity to effectively implement the process. Regional environmental assessment (REA) has shown to be effective in supporting decision-making not only to correct environmental problems due to past unsustainable social-economic developments but also help local governments to implement sustainable actions. However this requires long-term investments of AG21 plans and projects. The allocation of regular and consistent financial resources is one of the main ingredients for the sustainable development process. But traditional plans and projects financed by national and/or international funds may not be sustainable in the long-term because they become dependent on external funding. Research demonstrate that innovative economic instruments such as ecotaxes represent a feasible alternative to sponsor local sustainability because taxes are collected permanently by the government and could be invested in continuous actions. Ecotaxes experiences have provided important reference to structure a municipal incentive model (MIM) to sponsor AG21’s environmental plans and projects on a long-term (permanent) basis. However sustainable development cannot be solely through economic investments. A comprehensive municipal environmental management scheme (MEMS) has been established to support the incentive model. The scheme seeks not only to improve local institutional framework but also incentive continuous participation of local stakeholders at all levels of society. Participatory events and the provision of incentives (educational and financial) are key to motivate society to protect the environment and support actively the sustainable development process as emphasised in the RIO-92 Conference.  相似文献   
64.
我国海岸侵蚀灾害及对策   总被引:1,自引:0,他引:1  
赵全基 《灾害学》1992,7(4):39-42
文章通过大量实际资料展现了我国海岸侵蚀灾害的严重性;从入海泥沙、人类活动、地面沉降、海岸特性、海平面上升等方面分析了造成海岸侵蚀的原因;提出了一系列防治海岸侵蚀灾害的对策。  相似文献   
65.
农村水资源及其相关设施的改革需要更多了解村和户层次上的现实状况和机制安排。以避免改革扭曲和失败。通过对湖北和广西共四个村的村委会、关键知情人及120个农户的调查。在村和农户两个层次上描述水资源及其相关设施的管理与利用,尤其是在干旱年份村和户所采取的策略。并深入分析了农村村级水资源管理与利用的制度安排与问题。得出的结论是。追求水利管理效率的市场化改革需要考虑干旱的威胁,要有基于风险的制度设计和法律保障。  相似文献   
66.
山东省正处于工业化的中期阶段。矿产资源可持续利用面临重大挑战。本文分析了我国矿业大省——山东省的矿产资源开发利用存在的问题。提出山东省提高矿产资源的保障能力、促进矿产资源可持续利用的对策建议。  相似文献   
67.
ABSTRACT: This paper describes the formulation of an Index of Water Quality to evaluate the level of pollution in fresh water. A Four-Round Delphi equation, using a panel of seven nationally recognized water scientists, was performed to ascertain the pollutants to be included in the index, the relationship between the quantity of these pollutants in the water and the resulting quality of the water, and the importance of each pollution variable to each water use as well as to overall pollution. A multiplicative index was used to bring the pollutants together into one system.  相似文献   
68.
农业生产地域分工与农产品专业化生产是使农业从自然经济阶段向以市场为导向的商品农产品生产转变的一个标志。本文在分析该区农业布局现状及其存在问题的基础上,提出了农业总体布局的设想与不同类型地域农业开发的主攻方向与对策,并对市场经济体制下粮食、棉花、猪、禽、水产品等农产品生产基地的地域选择、建设规模与技术措施等进行了探讨。  相似文献   
69.
本文简要介绍区域性“减灾十年初步规划”编制的一般原则,包括规划编制的意义、目的、编制顺序和规划应注意的几个方面,并提出规划成果的实施意见。可供各地编制规划时参考。  相似文献   
70.
Indices of abundance and reproduction rate are considered in some groups of aquatic and terrestrial vertebrates from the zones of technogenic disasters. Upon a critical population decline caused by external destructive factors, such as emissions of acute ecotoxicants, the ecophysiological and behavioral compensatory mechanisms are activated, which provide for restoration of the total population size to the optimum within a short period of time. Environmental pollution with substances disturbing the reproductive function has the gravest consequences for animals. In this case, population size may remain fairly high, and, therefore, the effect of enhanced reproduction as a response to population decline does not take place, which eventually leads to a gradual but irreversible destruction of the population. Pathologies of reproduction should be used as a criterion for assessing the state of animals in the zones of technogenic disasters.Translated from Ekologiya, No. 1, 2005, pp. 32–38.Original Russian Text Copyright © 2005 by Shilova, Shatunovskii.  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