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151.
基于安全学习志的安全管理信息系统构建 总被引:1,自引:0,他引:1
通过分析论述安全学习志及安全管理信息系统的发展与特点,提出基于安全学习志安全管理信息系统的逻辑结构、总体构架和功能结构,以及从方法和技术角度为“安全学习志”在企业安全管理的应用提供一个全新的实现方案。本文把安全学习志这种理念融入到企业安全管理中,并对安全应急决策系统综合理论及安全管理信息系统建立技术方案的研究,目的在于为今后进一步的安全管理信息系统开发作理论和技术方法探索。 相似文献
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155.
安全管理新概念--关于"安全学习志"的探讨 总被引:2,自引:1,他引:2
本文提出了一种基于安全学习志的安全管理新概念.安全学习志是一种用于解答安全管理难题,将组织的经验知识转化为行动的管理工具.它继承了中华民族修志写史的优良文化传统,同时也借鉴了国外商业领域利用学习志集中学习互动的优点.具体从编撰方法、功能作用、推广应用及发展前景等几个方面阐述了这种管理概念的可行性. 相似文献
156.
基于土地利用变化的生态服务价值损益估算--以大庆市为例 总被引:21,自引:0,他引:21
土地利用/覆盖变化遥感研究表明,大庆市自1988年以来土地利用状态变化很大,由此引起了该区域生态环境的一系列响应及其生态系统服务价值的变化。以大庆市1988年和2001年的Landsat TM图像解译数据为基础,应用Costanza等人对全球生态系统服务价值的测算方法,分析了该市土地利用变化及其所引起的生态系统服务价值的变化。研究结果表明,13年间,大庆市土地利用的变化损害了该区域生态系统的生态服务功能,使生态系统服务价值损失了20.76%-24.01%。 相似文献
157.
TIM (Threat Identification Model) is a framework for the ex ante assessment of agricultural land management sustainability at the land unit scale that identifies sources of unsustainability within agricultural land management systems. The model explicitly links defined hazards to land productivity and environmental integrity, land resource data and information, and land management practice options using expert and local knowledge on land management and its potential effects. The model was tested in the Crystal Creek Subcatchment, a narrow coastal strip of land situated in north Queensland, Australia. This area was chosen due to the expansion of the sugar industry onto increasingly marginal land in the area, which represents a threat to sustainable land use and a requirement for careful land-use planning and land management.TIM may be used in a relational database as a stand alone decision support system for land-management planning. Its usefulness in land-use planning is greatest when it is linked to a Geographic Information System (GIS) as shown in this paper. GIS allows TIM outputs, such as constraints to agriculture and site-specific best-management practices, to be identified in a spatially explicit manner.The main advantages of TIM are that it can be done ex ante, it removes the need to define sustainability assessment criteria and indicators, it utilises current understanding of the causes and effects of land degradation and how different land-management practices influence these, and links this knowledge to definite land-management options. 相似文献
158.
Female choice and male–male aggression are two modes of sexual selection that can lead to elaboration of male morphological
and behavioral traits. In lek-mating species, male mating success is often strongly skewed, and it is puzzling why variation
in male traits is still observed given directional female choice. If male traits correlated with reproductive success are
honest signals of male quality, there may be survival costs associated with the expression of those traits. In this study,
we examined whether morphological, behavioral, and territorial traits are correlated with male mating success and survival
in the lek-mating greater prairie-chicken (Tympanuchus cupido). We introduce a novel application of multinomial discrete choice models for analysis of female mate choice behavior. We
found that behavioral and territorial attributes showed 6.5 times more variability among males than morphological traits.
Both display and aggressive behaviors were strong predictors of male mating success, suggesting that both female choice and
male–male aggression were important in determining mating success among male greater prairie-chickens. Moreover, annual survival
of male prairie-chickens was independent of mating success and male traits. Females appear to be choosing males based on behavioral
traits where large variation exists between males (coefficient of variation >30%). Behavioral traits were the most important
factor in determining mating success of male prairie-chickens, but the mechanism underlying this relationship is unknown.
In the future, experimental manipulations of male hormones or parasite loads could bridge the proximate mechanisms and ultimate
consequences of factors mediating male mating success in lek-mating grouse. 相似文献
159.
Facultative joint colony founding by social insects provides opportunities to analyze the roles of genetic and ecological
factors in the evolution of cooperation. Although cooperative nesting is observed in range of social insect taxa, the most
detailed studies of this behavior have been conducted with Hymenoptera (ants, bees, and wasps). Here, we show that foundress
associations in the haplodiploid social thrips Dunatothrips aneurae (Insecta: Thysanoptera) are most often comprised of close relatives (sisters), though groups with unrelated foundresses are
also found. Associations among relatives appear to be facilitated by limited female dispersal, which results in viscous population
structure. In addition, we found that per capita productivity declined with increasing group size, sex ratios were female-biased,
and some female offspring apparently remained in their natal domicile for some time following eclosion. D. aneurae thus exhibits a suite of similarities with eusocial Hymenoptera, providing evidence for the convergent evolution of associated
social and life-history traits in Hymenoptera and Thysanoptera. 相似文献
160.
Insect larvae increase in size with several orders of magnitude throughout development making them more conspicuous to visually
hunting predators. This change in predation pressure is likely to impose selection on larval anti-predator behaviour and since
the risk of detection is likely to decrease in darkness, the night may offer safer foraging opportunities to large individuals.
However, forsaking day foraging reduces development rate and could be extra costly if prey are subjected to seasonal time
stress. Here we test if size-dependent risk and time constraints on feeding affect the foraging–predation risk trade-off expressed
by the use of the diurnal–nocturnal period. We exposed larvae of one seasonal and one non-seasonal butterfly to different
levels of seasonal time stress and time for diurnal–nocturnal feeding by rearing them in two photoperiods. In both species,
diurnal foraging ceased at large sizes while nocturnal foraging remained constant or increased, thus larvae showed ontogenetic
shifts in behaviour. Short night lengths forced small individuals to take higher risks and forage more during daytime, postponing
the shift to strict night foraging to later on in development. In the non-seasonal species, seasonal time stress had a small
effect on development and the diurnal–nocturnal foraging mode. In contrast, in the seasonal species, time for pupation and
the timing of the foraging shift were strongly affected. We argue that a large part of the observed variation in larval diurnal–nocturnal
activity and resulting growth rates is explained by changes in the cost/benefit ratio of foraging mediated by size-dependent
predation and time stress. 相似文献