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31.
Urban waste management is one of the most complex and urgent challenges that the society faces. In this paper, an innovative research methodology is proposed, introducing a systemic approach to circular waste management strategy‐making. Urban waste management is a complex system that needs to be tackled in a holistic, yet context‐specific manner. To produce truly integrative outcomes, this paper provides insight into the system as a whole, its components and the relationships between them, using specific tools, to form the basis for a circular strategy. A toolbox is presented for transforming the current linear and fragmented waste management processes into integrative and circular strategies. The proposed integrative methodology encompassing outline, multipillar mapping, and synthesis can be applied to different locations and waste streams. The concept is subsequently demonstrated through a case study focusing on the municipality of Amsterdam (the Netherlands) and the management of organic waste streams. 相似文献
32.
Peter Schausberger 《Behavioral ecology and sociobiology》2005,58(1):53-59
A crucial question with respect to imprinting is how animals ensure that kin imprint on kin but not on non-kin. Imprinting takes place in a sensitive ontogenetic phase, usually in an early period of life or when offspring are produced, at which time the recipient imprints on the first referents met. In the predatory mite Phytoseiulus persimilis, imprinting among immature individuals happens in the larval stage immediately after hatching. I tested the hypothesis that adult P. persimilis females manipulate offspring imprinting by influencing the likelihood of encounters among recipients and referents via egg placement and egg aggregation. I conducted two experiments, one of which addressed imprinting and cannibalism, and the other addressed egg placement and egg aggregation. The imprinting experiment suggests that larvae imprint on any conspecific individual met in a sensitive ontogenetic phase and later on treat this individual as kin, irrespective of relatedness. After molting to protonymphs, imprinted individuals preferentially cannibalized unfamiliar to familiar larvae. Irrespective of familiarity, kin were cannibalized earlier than non-kin, suggesting the involvement of self-referent phenotype matching. The egg-placement experiment provides evidence that females adjust the aggregation level of their own eggs according to the degree of relatedness to present eggs from a previously ovipositing female. Both experiments in concert suggest that egg placement is a maternal strategy influencing imprinting among immature individuals. Apart from avoiding kin cannibalism, egg placement and imprinting by larvae may have relevance to other behaviors influenced by kin recognition, such as mate choice, prey-patch choice and dispersal.Communicated by L. Simmons 相似文献
33.
黑龙江省地质灾害防治与环境保护策略分析 总被引:1,自引:1,他引:1
地质灾害与地质环境是一对互为影响、互为关联的矛盾统一体。地质灾害是在特定的地质环境条件下孕育发展的,它的发生受到其所处地质环境的制约。反过来,地质灾害对地质环境又具有改造作用,经常会导致产生新的、更大的地质灾害,形成恶性循环,制约经济、社会的可持续发展。因此,防治地质灾害和保护好地质环境是人类在经济、社会发展中面临的重要任务。地质灾害防治与地质环境保护是互利的,灾害的防治是环境质量的保证,环境条件的改善则可在一定程度上制约灾害的发生或降低灾害的程度和频度。如此同步进行可有效防灾,有效保护环境。分析了黑龙江省地质灾害概况和主要地质环境问题;探讨了地质灾害防治和地质环境保护两者之间的关系;并根据该省地质灾害频繁发生和地质环境日益恶化的现实及减灾工作现状,提出了今后加强地质灾害防治和地质环境保护工作的若干建议。 相似文献
34.
以磁流变阻尼器所在层的层间位移和层速度响应为输入变量,以控制电流为输出变量,根据抗震规范和实际经验提出了模糊控制器的合理的设计方法。对一个3层钢筋混凝土结构进行了实例分析,结果表明,模糊控制无论是对于位移响应还是加速度响应都有较好的控制效果。 相似文献
35.
36.
我国海岸带灾害成因分析及减灾对策 总被引:14,自引:1,他引:14
近年来海岸带灾害越来越成为制约海岸带-我国最重要的经济带社会、经济和环境可持续发展的重要因素。本文在全球变化和人类活动影响的背景下,分析探讨了我国海岸带灾害的基本成因,并提出了相应的概念性减灾对策框架,海岸带生态环境的脆弱性,全球变化(相对海平面变化、气候异常)和人类活动是导致我国海岸带灾害的3个主要方面。据此,认为减灾的关键在于合理规范人类行为,保护和改善本已十分脆弱的海岸带生态环境,使人与自然界和谐相处;对于全球变化诱发的灾害,则力求基于科学认识与预测,在海岸带开发中合理规划建设,做到未雨绸缪,实现海岸带社会经济可持续发展。 相似文献
37.
超补偿理论及其在虫害控制中的意义 总被引:3,自引:0,他引:3
本文较为系统地阐述了作物对虫害损伤的超补偿理论,表明超补偿广泛存在于各种作物中,并对超补偿所需条件、基本原因以及与害虫控制的关系作进一步讨论。 相似文献
38.
关于中国企业品牌战略的研究 总被引:2,自引:0,他引:2
陈威 《湖南环境生物职业技术学院学报》2009,15(1):39-42
为使中国企业更好的应对国外品牌的竞争,稳健的实施企业品牌战略,该文就我国企业实施品牌战略的现状以及存在的问题进行了分析,有针对性的提出了具体在实施品牌战略过程中应特别注意并实行有效调控的对策。参4. 相似文献
39.
Managing mangroves in Bangladesh: A strategy analysis 总被引:1,自引:0,他引:1
Bangladesh, favoured by a tropical climate, houses the world’s largest stretch of mangroves forests (Sundarbans Reserved Forest)
and plantations. Around half of the forests of the country occur in the coastal zone. People extract various goods and services
from the mangroves. Nevertheless the mangrove forests are depleting. Although the extent of the Sundarbans forest has not
changed much, its decline is of a qualitative nature. Mangrove plantations are increasing in area but they are losing growing
stock. To arrest this, Bangladesh has adopted several strategies.
The ‘Sustainable Ecosystem Management’ strategy has now been adopted instead of the ‘Sustained Yield Principle’. Biodiversity
conservation and enhancement has been taken as a key management goal. A zoning system is being developed for both production
and protection purposes. The government facilitates alternative income for the local people by generating activities for the
communities which are dependent on the forest. Different non-governmental organizations collaborate with the government in
reducing the local people’s dependence on the forest. Coastal plantations are erected to protect people from cyclones and
to make the land more suitable for habitation. Through this greening of the coastal belt tree plantation is encouraged in
coastal villages. Coastal embankments are being planted and leased to poor settlers in exchange for routine maintenance of
the embankments. Plantations on newly accreted mud flats help in stabilizing the land, which can later on be settled by victims
of erosion elsewhere. These adopted management measures do not only contribute to forestry resource management but also to
the social, environmental and economic wellbeing of the coastal communities. These efforts are at present being integrated
into an Integrated Coastal Zone Management (ICZM) project. 相似文献
40.
We conducted field surveys and laboratory analyses to test the effects of soil characteristics in habitat mitigation sites and natural sites on the growth and condition of blue elderberry (Sambucus mexicana), which is the sole host plant for the federally threatened Valley elderberry longhorn beetle (Desmocerus californicus dimorphus). Thirty mitigation and 16 natural sites were selected throughout the range of the beetle. We found that although plant relative growth rates were comparable between mitigation sites and a natural site, mitigation sites contained substantially less soil nutrients than mitigation sites. Within mitigation sites, elderberry health and growth were positively correlated with the amount of total nitrogen in soils and less strongly with other soil nutrients and soil moisture. Analyses demonstrated reductions in the relative growth rate of elderberry as mitigation sites aged, and that soil nutrients and soil moisture became depleted over time. For mitigation sites, it took approximately seven years to develop basal stem diameters that have been linked to successful beetle colonization. Mitigation sites have smaller shrubs than natural sites and growth slows as mitigation sites age, thus delaying convergence of conditions between natural and mitigation sites. Analyses of soil particle size and whether sites were within the 100-year floodplain (as an indicator of riparian conditions) were inconclusive. We recommend investigating fertilizing and optimum planting densities for elderberry at restoration and mitigation sites, as well as increasing the duration of irrigation and monitoring. 相似文献