全文获取类型
收费全文 | 327篇 |
免费 | 6篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 2篇 |
环保管理 | 158篇 |
综合类 | 45篇 |
基础理论 | 77篇 |
污染及防治 | 41篇 |
评价与监测 | 4篇 |
社会与环境 | 7篇 |
灾害及防治 | 1篇 |
出版年
2022年 | 5篇 |
2021年 | 12篇 |
2020年 | 1篇 |
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 5篇 |
2016年 | 18篇 |
2015年 | 8篇 |
2014年 | 7篇 |
2013年 | 18篇 |
2012年 | 6篇 |
2011年 | 23篇 |
2010年 | 9篇 |
2009年 | 31篇 |
2008年 | 18篇 |
2007年 | 24篇 |
2006年 | 13篇 |
2005年 | 9篇 |
2004年 | 6篇 |
2003年 | 14篇 |
2002年 | 6篇 |
2001年 | 11篇 |
2000年 | 12篇 |
1999年 | 8篇 |
1998年 | 3篇 |
1997年 | 6篇 |
1996年 | 9篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 7篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 5篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有335条查询结果,搜索用时 359 毫秒
251.
H. Doing 《Journal of Coastal Conservation》1995,1(2):145-172
This paper is a summary and elaboration of an earlier publication in Dutch on the compilation of a landscape-ecological map,
scale 1 : 50 000, of the Dutch coast. It is argued that such an integrated map is the best basis for the conservation and
management of the coastal dunes and salt marshes. It may be combined with local more detailed vegetation maps, some examples
of which are mentioned in the context of management.
The Dutch North Sea coast is a ca. 350 km long chain of sandy beaches and sand dunes, from only 100 m to more than 10 km wide.
On sheltered stretches of dune coasts along estuaries in the Southwest and on the Wadden Sea islands, salt marshes have developed.
The small-scale gradient structure of the beach-dune-salt marsh complex is emphasized. 相似文献
252.
浙江省生物多样性保护对策研究 总被引:5,自引:0,他引:5
由于森林的破坏与片段化、湖泊面积缩小、水域污染、滩涂湿地围垦和物种资源过度开发利用等原因,使生物多样性严重受协。在对浙江省生物多样性保护进行系统研究的基础上,提出了浙江省生物多样性保护的目标和主要对策。 相似文献
253.
In many countries, a large proportion of forest biodiversity exists on private land. Legal restrictions are often inadequate to prevent loss of habitat and encourage forest owners to manage areas for biodiversity, especially when these management actions require time, money, and other resources. Environmental programs encouraging these actions through economic incentives can be used instead of additional legal restrictions, although to be efficient and successful, an incentive program must be thoughtfully developed and its conservation goals must be clear. In addition to being economically efficient, programs must be acceptable to landowners and ecologically appropriate, especially with respect to the case-specific objectives and the ecosystems in question. We introduce a sample of voluntary incentive programs for private forests in Europe and North America. We briefly describe the economic, social, and ecological characteristics of the programs and the forests they aim to conserve, and evaluate the success of these programs with respect to their explicitly stated goals and the ecological status of the forests in that country or state. Important factors contributing to program success include an allowance for some economic productivity in enrolled forests, a long period since time of program inception, and little interference from other incentive programs. 相似文献
254.
鄱阳湖候鸟保护区的自然环境 总被引:2,自引:0,他引:2
根据较丰富的第一手资料,叙述了鄱阳湖候鸟保护区内的自然环境因素:气候、水文、水质、动植物资源等。调查表明,保护区内冬季气候温和,平均气温在5.0℃以上,平均水温为6.2℃,每年10月至次年3月的气温、水温和水深适宜候鸟越冬;水质较好;水陆动植物和鸟类资源丰富,有许多国家级保护鸟类,如白鹤、小天鹅等。文章最后呼吁,要切实保护好鄱阳湖这块世界A级自然保护区,增划一些禁猎区、广泛开展爱鸟活动,形成依法护鸟,全民爱鸟的社会风气。 相似文献
255.
红树林生态系统服务功能及其保护 总被引:4,自引:0,他引:4
红树林有多种生态系统服务功能,包括促进渔业生产,护岸减灾,保护生物多样性,改善环境质量等,中国红树植物种类少,分布范围窄,资源面积小,质量差,尤其人类活动加剧了其脆弱和濒危程度,近年程度工作有一定进展,资源有所恢复,但仍需正确处理沿海地区发展和红树林生态系统保护的关系,在国土资源保护中给予红树林最高保护等级的地位。 相似文献
256.
Ants are abundant, diverse, and ecologically dominant in tropical forests. Subterranean ants in particular are thought to
have a significant environmental impact, although difficulties associated with collecting ants underground and examining their
ecology and behavior have limited research. In this paper, we present the results of a study of subterranean ant diversity
in Amazonian Ecuador that employs a novel probe to facilitate the discovery of species inhabiting the soil horizon. Forty-seven
species of ants in 19 genera, including new and apparently rare species, were collected in probes. Approximately 19% of the
species collected at different depths in the soil were unique to probe samples. Analysis of similarity (ANOSIM) results showed
that the species composition of ants collected with the probe was significantly different from samples collected using other
techniques. Additionally, ANOSIM computations indicated the species assemblage of ants collected 12.5 cm below the surface
was significantly different from those found at 25, 37.5, and 50 cm. Ant diversity and species accumulation rates decreased
with increasing depth. There were no species unique to the lowest depths, suggesting that subterranean ants may not be distributed
deep in the soil in Amazonia due to the high water table. The technique we describe could be used to gain new insights into
the distribution and biology of subterranean ant species and other members of the species-rich soil invertebrate macrofauna. 相似文献
257.
As with many farmland bird species, the house sparrow Passer domesticus is declining in Europe, mainly due to intensification of agriculture reducing nest sites and food supplies. During 2002–2005,
we studied the population size and nest site characteristics of house sparrows breeding within white stork Ciconia ciconia nests in a large area of agricultural landscape within western Poland. To explain sparrow density within stork nests, we
examined characteristics of white stork nests (position, age, productivity) and the farm type around the nest. House sparrow
density was greatest in the longest established (and hence larger) white stork nests located on traditionally managed farms.
Two recent changes appear to have adverse effects on house sparrows. The first is the intensification of farming and the second
is active management of white stork nests on electric poles to reduce nest size and thus avoid both disruption to the electrical
supply and electrocution of white storks. Because the white stork has such a high profile in Poland, there are numerous schemes
to conserve and enhance this species. In conclusion, we clearly show that protecting one species can have valuable, although
unplanned, benefits to another species of conservation interest, the house sparrow. 相似文献
258.
259.
Kyle A. Young 《Environmental management》2000,26(2):131-144
Oncorhynchus sp.), regional governments now restrict timber harvest in riparian forests. I summarize and assess the riparian zone management
guidelines of the states of California, Oregon, and Washington (USA) and the province of British Columbia (Canada). Only Oregon
and British Columbia protect fish-bearing streams with “no-harvest” zones, and only the wider (20–50 m) no-harvest zones for
larger fish-bearing streams in British Columbia are likely to maintain near-natural linkages between riparian and stream ecosystems.
All four jurisdictions protect most streams with “management zones” of variable width, in which timber harvest activities
are restricted. All the management zone guidelines permit the harvest of the largest conifers from riparian forests and will,
if applied over a series of timber harvest rotations (60–80 years), result in the continued removal of potential sources of
large woody debris from the region's watersheds. All four jurisdictions require additional protection for streams and watersheds
that are severely degraded or (in the United States) contain threatened or endangered species. The governments of the PNW
have taken a “manage until degraded, then protect” approach to riparian forest management that is unlikely to maintain or
restore the full suite of riparian-stream linkages necessary for lotic ecosystems to function naturally at the stream, watershed,
basin, or regional scale. 相似文献
260.
Nesting biodiversity conservation into landscape management 总被引:3,自引:0,他引:3
Eduardo R. Fuentes-Quezada Nikhil Sekhran and Arundhati Kunte-Pant 《Natural resources forum》2000,24(2):83-95
There is universal recognition that biological diversity (biodiversity) is being lost at an alarming rate. The costs and risks of these losses for humanity are still not fully understood, but are believed to be very significant. While much is being achieved through conservation programmes, the task of addressing the current crisis remains complex, particularly as there are significant biological, social and economic challenges to nesting conservation objectives into land-use management. This paper emphasizes the socio-economic challenges, wherein a central issue is that of equitably sharing the costs and benefits of conservation among all beneficiaries, nationally and internationally. The world's biological heritage supplies mankind with a number of ecological goods and services, which have attached direct use values, indirect use values, existence values and option values. Currently, only a few direct values are tangible and here much remains to be done to capture effectively and distribute equitably the benefits arising from the other values. The paper discusses three instances where some of these challenges are being addressed, in Belize, Pakistan and Mongolia. Finally, the paper discusses the need for additional mechanisms that will help meet the challenge of establishing and maintaining conservation arrangements in the landscapes of developing countries, where much of the most threatened biota is found. 相似文献