全文获取类型
收费全文 | 33136篇 |
免费 | 369篇 |
国内免费 | 469篇 |
专业分类
安全科学 | 983篇 |
废物处理 | 1612篇 |
环保管理 | 3848篇 |
综合类 | 5548篇 |
基础理论 | 8548篇 |
环境理论 | 22篇 |
污染及防治 | 8952篇 |
评价与监测 | 2342篇 |
社会与环境 | 1935篇 |
灾害及防治 | 184篇 |
出版年
2023年 | 172篇 |
2022年 | 422篇 |
2021年 | 406篇 |
2020年 | 281篇 |
2019年 | 321篇 |
2018年 | 592篇 |
2017年 | 562篇 |
2016年 | 891篇 |
2015年 | 651篇 |
2014年 | 1054篇 |
2013年 | 2694篇 |
2012年 | 1235篇 |
2011年 | 1600篇 |
2010年 | 1300篇 |
2009年 | 1292篇 |
2008年 | 1590篇 |
2007年 | 1631篇 |
2006年 | 1399篇 |
2005年 | 1171篇 |
2004年 | 1059篇 |
2003年 | 1143篇 |
2002年 | 1005篇 |
2001年 | 1268篇 |
2000年 | 884篇 |
1999年 | 536篇 |
1998年 | 354篇 |
1997年 | 364篇 |
1996年 | 359篇 |
1995年 | 442篇 |
1994年 | 457篇 |
1993年 | 360篇 |
1992年 | 376篇 |
1991年 | 355篇 |
1990年 | 390篇 |
1989年 | 348篇 |
1988年 | 298篇 |
1987年 | 282篇 |
1986年 | 225篇 |
1985年 | 252篇 |
1984年 | 265篇 |
1983年 | 257篇 |
1982年 | 245篇 |
1981年 | 222篇 |
1980年 | 176篇 |
1979年 | 196篇 |
1978年 | 176篇 |
1975年 | 143篇 |
1974年 | 118篇 |
1972年 | 131篇 |
1971年 | 132篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
231.
REED F. NOSS ERICA FLEISHMAN† DOMINICK A. DELLASALA‡ JOHN M. FITZGERALD§ MART R. GROSS MARTIN B. MAIN†† FIONA NAGLE‡‡ STACEY L. O'MALLEY JON ROSALES§§ 《Conservation biology》2009,23(4):825-833
Abstract: The Society for Conservation Biology (SCB) can enhance conservation of biodiversity in North America by increasing its engagement in public policy. Toward this end, the North America Section of SCB is establishing partnerships with other professional organizations in order to speak more powerfully to decision makers and taking other actions—such as increasing interaction with chapters—geared to engage members more substantively in science-policy issues. Additionally, the section is developing a North American Biodiversity Blueprint, which spans the continental United States and Canada and is informed by natural and social science. This blueprint is intended to clarify the policy challenges for protecting continental biodiversity, to foster bilateral collaboration to resolve common problems, and to suggest rational alternative policies and practices that are more likely than current practices to sustain North America's natural heritage. Conservation scientists and practitioners can play a key role by drawing policy makers' attention to ultimate, as well as proximate, causes of biodiversity decline and to the ecological and economic consequences of not addressing these threats. 相似文献
232.
Abstract: Indigenous people inhabit approximately 85% of areas designated for biodiversity conservation worldwide. They also continue to struggle for recognition and preservation of cultural identities, lifestyles, and livelihoods—a struggle contingent on control and protection of traditional lands and associated natural resources (hereafter, self‐determination). Indigenous lands and the biodiversity they support are increasingly threatened because of human population growth and per capita consumption. Application of the Endangered Species Act (ESA) to tribal lands in the United States provides a rich example of the articulation between biodiversity conservation and indigenous peoples' struggle for self‐determination. We found a paradoxical relationship whereby tribal governments are simultaneously and contradictorily sovereign nations; yet their communities depend on the U.S. government for protection through the federal‐trust doctrine. The unique legal status of tribal lands, their importance for conserving federally protected species, and federal environmental regulations' failure to define applicability to tribal lands creates conflict between tribal sovereignty, self‐determination, and constitutional authority. We reviewed Secretarial Order 3206, the U.S. policy on “American Indian tribal rights, federal–tribal trust responsibilities, and the ESA,” and evaluated how it influences ESA implementation on tribal lands. We found improved biodiversity conservation and tribal self‐determination requires revision of the fiduciary relationship between the federal government and the tribes to establish clear, legal definitions regarding land rights, applicability of environmental laws, and financial responsibilities. Such actions will allow provision of adequate funding and training to tribal leaders and resource managers, government agency personnel responsible for biodiversity conservation and land management, and environmental policy makers. Increased capacity, cooperation, and knowledge transfer among tribes and conservationists will improve biodiversity conservation and indigenous self‐determination. 相似文献
233.
Abstract: We reviewed the evidence on the extent and efficacy of conservation of tropical forest biodiversity for each of the classes of conservation action defined by the new International Union for Conservation of Nature (IUCN) classification. Protected areas are the most tested conservation approach, and a number of studies show they are generally effective in slowing deforestation. There is some documentation of the extent of sustainable timber management in tropical forest, but little information on other landscape‐conservation tactics. The extent and effectiveness of ex situ species conservation is quite well known. Forty‐one tropical‐forest species now survive only in captivity. Other single‐species conservation actions are not as well documented. The potential of policy mechanisms, such as international conventions and provision of funds, to slow extinctions in tropical forests is considerable, but the effects of policy are difficult to measure. Finally, interventions to promote tropical conservation by supporting education and livelihoods, providing incentives, and furthering capacity building are all thought to be important, but their extent and effectiveness remain poorly known. For birds, the best studied taxon, the sum of such conservation actions has averted one‐fifth of the extinctions that would otherwise have occurred over the last century. Clearly, tropical forest conservation works, but more is needed, as is critical assessment of what works in what circumstances, if mass extinction is to be averted. 相似文献
234.
235.
236.
237.
238.
239.
240.