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581.
I. P. Belousova K. A. Smirnov V. D. Kaz’min I. V. Kudrjavtsev 《Russian Journal of Ecology》2005,36(2):115-119
The forest ecosystem of the Orlovskoe Polese National Park has been studied in reference to the reintroduction of a rare species: the European bison (Bison bonasus L.). Preliminary data characterizing the state of forest resources and the populations of ungulates living in the forests, as well as the genetic problems associated with maintaining a viable population of the European bison, are considered.Translated from Ekologiya, No. 2, 2005, pp. 132–137.Original Russian Text Copyright © 2005 by Belousova, Smirnov, Kazmin, Kudrjavtsev. 相似文献
582.
Summary The biomass and productivity of a montane grassland of Garhwal Himalaya were estimated with the objectives to compare these
values of the dominant exotic species, Eupatorium glandulosum HBK. (Asteraceae) with other species, and to compare the sites more dominated by this species with other study sites. The
effect of dominance of this species on other species was undertaken because of its continuous spread in the grasslands of
the Garhwal Himalaya causing replacement of some native grasses and economically important herbaceous plants. Out of six study
sites, SW1, SW2, and NE1 were more dominated by Eupatorium glandulosum. Total net primary productivity (TNP) ranged from 1528.5 to 2163.4 g m−2 yr−1. Eupatorium glandulosum showed individual highest biomass on all the study sites, and the sites more dominated by this species showed higher values
of primary productivity, thereby reducing the biomass and production of other species on these sites. 相似文献
583.
依据消防法律法规赋予森林公安派出所的消防监督职能,结合林区实际,对派出所实施消防监督检查、火灾案件调查、消防宣传提出了建设性意见. 相似文献
584.
Stanley L. Ponce 《Journal of the American Water Resources Association》1979,15(2):530-535
ABSTRACT: A survey was made to determine the status of formal education in wildland hydrology by colleges and universities in the United States, Canada, and Mexico. As of December 1977 nine institutions offered the B.S. degree, 18 the M.S. degree, and 17 the degree of Ph.D. with a major or minor in watershed management, forest hydrology, or range hydrology. In addition, 8 other schools offer a minor in watershed management. The survey indicated 44 schools in the United States offer a total of 157 courses, five schools in Canada offer 24 courses, and 1 in Mexico offers one course in the related areas. The survey illustrated rapid growth in education programs and it is anticipated that growth will continue. 相似文献
585.
本文创造性地提出了国有林场“三工”合同管理的新模式,走法制化的道路,首先必须理顺国有林场与“三工”与“三工”组织的劳动关系,依照《劳动法》与《合同法》,分清各自的权利和义务,然后逐步由“三工”组织劳动合同向经济承揽合同过渡,依法解决合同管理中存在的问题。 相似文献
586.
Linnell JD Andersen R Kvam T Andrén H Liberg O Odden J Moa PF 《Environmental management》2001,27(6):869-879
Annual and seasonal home ranges were calculated for 47 Eurasian lynx in four Scandinavian study sites (two in Sweden and two
in Norway). The observed home ranges were the largest reported for the species, with study site averages ranging from 600
to 1400 km2 for resident males and from 300 to 800 km2 for resident females. When home range sizes were compared to the size of protected areas (national parks and nature reserves)
in Scandinavia, it was concluded that very few protected areas contained sufficient forest to provide space for more than
a few individuals. As a direct consequence of this, most lynx need to be conserved in the multiuse seminatural forest habitats
that cover large areas in Scandinavia. This conservation strategy leads to a number of conflicts with some land uses (sheep
and semidomestic reindeer herding, and roe deer hunters), but not all (forestry and moose harvest). Accordingly research must
be aimed at understanding the ecology of these conflicts, and finding solutions. 相似文献
587.
The effects of aspect, altitude, and slope have been observed on the moist temperate forests of Abies pindrow Spach in the Garhwal Himalaya, India. Four aspects, namely, north-east, north-west, south-east and south-west, have been studied to understand the growth behaviour of A. pindrow at varying altitudes. The total basal cover was found to be highest (5099.6 cm2/100 m2) on the north-east facing slopes, and lowest (3092.7 cm2/100 m2) on the south-east facing slopes. The A. pindrow was found to be associated with Quercus semecarpifolia as a main companion species on all the faces, whereas, Lyonia ovalifolia, was associated only on the west facing slopes. 相似文献
589.
干旱区的山地是平原区河流的水源聚积地,而山地森林更是水源的涵养林,对保证和供给山下绿洲资源水源有重要调节作用,山地森林还在保持水土、生物多样性保护、旅游、文化、教育等多方面有重要生态作用。其生态经济价值是其本身木材价值的许多倍。但过去我们对森林的生态价值认识不足,林业部门只把它当资源进行过度砍伐,以获取直接经济效益,新疆天山及阿尔泰山水源涵养林自50年代以来能砍的几乎全部砍完,仅剩两条山脉西端小面积残存未砍伐的原始森林。为了子孙后代,为了环保工程,应立即停伐。 相似文献
590.
Why the Conservation of Forest Genetic Resources Has Not Worked 总被引:3,自引:0,他引:3
Abstract: Genetic diversity is indispensable for long-term forest sustainability and is therefore mentioned in numerous binding and nonbinding political covenants calling for action. Nevertheless, there are significant obstacles to the conservation of forest genetic resources. We discuss hindrances to genetic conservation, mainly in Europe. We identified impediments by reviewing the literature and on the basis of the experiences of the authors in this field and their participation in related political processes. The impediments include (1) difficulties in assessing and monitoring genetic erosion and human impacts (e.g., by the lack of markers showing adaptive variation and the lack of record keeping on the use and transfer of forest-tree germplasm), (2) complexities of European national structures that make the development of a common strategy toward forest genetic conservation problematic, (3) lack of effective forest governance in many parts of the world, (4) the general unattractiveness of genes as flagships in raising public awareness, (5) lack of integration of genetic aspects into biodiversity conservation, and (6) the fact that scientists and politicians are often at cross-purposes. To overcome these impediments, forest geneticists and their peers in species conservation have to participate more actively in decision making. In doing so, they must be prepared to face challenges on 2 fronts: participating in political processes and the provision of significant research findings to ensure that decisions with respect to forest genetic diversity are politically implementable and effectively address targets. 相似文献