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   1061篇
  免费   104篇
  国内免费   145篇
安全科学   36篇
废物处理   5篇
环保管理   272篇
综合类   482篇
基础理论   257篇
污染及防治   40篇
评价与监测   59篇
社会与环境   128篇
灾害及防治   31篇
  2024年   4篇
  2023年   17篇
  2022年   37篇
  2021年   65篇
  2020年   42篇
  2019年   47篇
  2018年   32篇
  2017年   43篇
  2016年   57篇
  2015年   44篇
  2014年   62篇
  2013年   83篇
  2012年   70篇
  2011年   74篇
  2010年   75篇
  2009年   63篇
  2008年   58篇
  2007年   68篇
  2006年   49篇
  2005年   44篇
  2004年   44篇
  2003年   47篇
  2002年   27篇
  2001年   22篇
  2000年   24篇
  1999年   10篇
  1998年   15篇
  1997年   10篇
  1996年   14篇
  1995年   4篇
  1994年   15篇
  1993年   7篇
  1992年   5篇
  1991年   5篇
  1990年   5篇
  1989年   5篇
  1988年   3篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1984年   1篇
  1978年   2篇
  1977年   2篇
  1974年   1篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1970年   1篇
排序方式: 共有1310条查询结果,搜索用时 151 毫秒
101.
农村污染防治工作已迫在眉睫   总被引:1,自引:0,他引:1  
于永斌 《四川环境》2007,26(1):112-114
针对目前农村经济发展过程中出现的主要环境问题,结合农村的实际情况,提出了解决农村环境污染问题的几项措施。并着重分析了规模化畜禽养殖业中的环境污染问题,提出了综合防治对策。  相似文献   
102.
典型区耕地变化与GDP值变化的脱钩研究   总被引:3,自引:0,他引:3  
研究目的:为了深入分析耕地占用与GDP值增长之间的关系,研究不同区域之间耕地数量变化与GDP值变化的差异性与相似性,有利于平衡耕地占用与GDP值增长之间的矛盾,同时有利于“状态-压力-响应”体系的研究。研究方法:主要是应用脱钩理论,引入了脱钩指数来分析不同区域各时点耕地数量变化与GDP值变化之间的关系,同时运用相关分析与回归分析的方法,确立了不同研究区耕地数量与社会经济指标之间的相关性,建立了耕地面积与GDP值的回归曲线。研究结论:耕地数量的变化与GDP值之间的关系因地域差异而表现不同,但是也存在一些相似点,即各个区域相对脱钩与绝对脱钩的年份基本一样;此外脱钩理论有利于进一步深化土地利用的研究。  相似文献   
103.
Sub‐Saharan Africa continues to face the daunting challenge of alleviating poverty due to slow economic growth. In southern Africa, most countries are adopting policies that promote the integration of biodiversity conservation and rural development to contribute to rural poverty alleviation. Numerous approaches have been undertaken in this endeavour, including Transfrontier Parks (TFPs) and Transfrontier Conservation Areas (TFCAs). This paper discusses some of the limitations of the TFPs. In conclusion I posit that unlike TFPs, which are state controlled and managed, TFCAs, which promote multi‐land use and multi‐stakeholder participation are attainable and have a higher probability of sustaining biodiversity conservation and contributing to the alleviation of rural poverty, if: (i) areas of high biodiversity conservation within communal areas can be identified, zoned and leveraged to biodiversity conservation and managed in partnership between the communities and the private sector; (ii) local communities can secure legal rights to their customary land being devoted to biodiversity conservation and use such pieces of land as collateral in negotiating partnerships with the private sector in developing conservation‐based enterprises; (iii) functional community natural resource governance institutions can be established and empowered to represent their constituencies in securing fair equity from profits made from sustainable use of the conserved biodiversity assets and tourism businesses; (iv) concerted effort can be invested in developing and implementing family planning and fertility reduction strategies that would slow down human population growth to levels that can be sustained by the available natural resources; and (v) if sustainable financing mechanisms can be developed, and the governance of protected areas occurring in the TFCAs can be broadened to include other stakeholders.  相似文献   
104.
The study presented in this article used a combination of key informant interviews and a review and synthesis of existing country level literature to identify the major sources of land tenure insecurity in six Southern African countries: Botswana, Lesotho, Malawi, Mozambique, South Africa, and Zambia. Findings reveal that the main causes of land tenure insecurity experienced in Southern Africa include lack of land rights of minority groups, unclear or overlapping land rights, overcrowding, land alienation into leasehold, insecurity of farm workers and farm labour tenants, inappropriate and exploitative administrative practices, land encroachment and illegal settlers and limited women's land rights. The article presents a summary of land tenure security related initiatives that the study countries have or are in the process of adopting. Analysis of these initiatives shows that tenure reforms have focused on changing the law and rules but little has been done to translate new laws into implementable programs; capacity building; prioritization of resources to support tenure reform; provision of complementary policies and incentives; addressing HIV/AIDS‐land tenure related problems; and monitoring and evaluation. The paper contends that these policy issues should be addressed in order to ensure realization of land tenure security for all.  相似文献   
105.
Abstract: Streams draining mountain headwater areas of the western Mojave Desert are commonly physically isolated from downstream hydrologic systems such as springs, playa lakes, wetlands, or larger streams and rivers by stream reaches that are dry much of the time. The physical isolation of surface flow in these streams may be broken for brief periods after rainfall or snowmelt when runoff is sufficient to allow flow along the entire stream reach. Despite the physical isolation of surface flow in these streams, they are an integral part of the hydrologic cycle. Water infiltrated from headwater streams moves through the unsaturated zone to recharge the underlying ground‐water system and eventually discharges to support springs, streamflow, isolated wetlands, or native vegetation. Water movement through thick unsaturated zones may require several hundred years and subsequent movement through the underlying ground‐water systems may require many thousands of years – contributing to the temporal isolation of mountain headwater streams.  相似文献   
106.
ABSTRACT. The Spring 1973 Mississippi River flood was investigated using remotely sensed data from ERTS-1. Both manual and automatic analyses of the data indicate that ERTS-I is extremely useful as a regional tool for flood management. Quantitative estimates of area flooded were made in St. Charles County, Missouri and Arkansas. Flood hazard mapping was conducted in three study areas along the Mississippi River using pre-flood ERTS-1 imagery enlarged to 1:250,000 and 1:100,000 scale. The flood prone areas delineated on these maps correspond to areas that would be inundated by significant flooding (approximately the 100 year flood). The flood prone area boundaries were generally in agreement with flood hazard maps produced by the U. S. Army Corps of Engineers and U. S. Geological Survey although the latter are somewhat more detailed because of their larger scale. Initial results indicate that ERTS-1 digital mapping of flood prone areas can be performed at 1:62,500 which is comparable to some conventional flood hazard map scales.  相似文献   
107.
以四川藏区矿产资源的开发利用为研究对象,一方面,从环境公害本土化的视角解读四川藏区的资源开发公害问题;另一方面,从法律的价值和应对的视角对资源开发公害问题进行法律规制,以期对四川藏区生态环境的保护有所裨益。  相似文献   
108.
农村生活固体垃圾的处理现状及影响因素   总被引:1,自引:0,他引:1  
随着我国农村经济与农民收入水平的快速提高,农村生活固体垃圾产生与排放的数量快速增加,已经严重影响了农村环境、农民健康和农业可持续发展.该文的主要目的是基于甘肃和河北省60个村和240个农户的调研资料,深入了解农村生活固体垃圾的处理和管理现状及影响生活固体垃圾有效处理的制约因素.结果表明,大多数村没有处理生活固体垃圾的设施,总体看甘肃省拥有的处理设施要好于河北省.超过一半的村中生活固体垃圾都没有人管理,但部分村开始制定相关的管理计划.描述性统计分析和计量模型的分析结果表明,农村生活固体垃圾的处理状况与农民人均收入水平的提高和交通便利程度的改进有显著正相关关系,而非农就业机会的增加不利于当地生活垃圾的处理.  相似文献   
109.
本文从分析我国传统的经济增长方式入手,通过对资源近视症”的表现及后果的分析,提出西部西地区,特别是西部少数民族地区只有树立全面的资源观,立足优势,面向市场,抓住机遇,合理开发资源和利用资源,才能走出一条符合本民族,本地区实际的可持续发展之路。  相似文献   
110.
长江下游典型滨海地区农业土壤重金属污染特征   总被引:1,自引:0,他引:1  
为揭示长江下游滨海地区农业土壤重金属污染状况,以滨江临海的南通市为例,网格化布点,采集表层农业土壤样品共计334个,对其重金属Cu、Pb、Cr、As、Hg含量进行了测定分析.结果表明,研究区域表层农业土壤中各重金属含量均已超过其背景值,且以Pb污染最为严重;区域性差异较大,以滨海的如东、海门、启东污染最为严重,且以海门、启东As含量最高;各重金属间相关性不显著,来源途径不止一种.从而提出南通市农业土壤重金属污染的防治应立足于防重于治的方针,着重滨海地区,以Pb、As污染源为主,并对污染土壤进行修复.  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