全文获取类型
收费全文 | 858篇 |
免费 | 6篇 |
国内免费 | 6篇 |
专业分类
安全科学 | 26篇 |
废物处理 | 52篇 |
环保管理 | 99篇 |
综合类 | 77篇 |
基础理论 | 179篇 |
环境理论 | 1篇 |
污染及防治 | 294篇 |
评价与监测 | 91篇 |
社会与环境 | 48篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 14篇 |
2022年 | 36篇 |
2021年 | 27篇 |
2020年 | 16篇 |
2019年 | 19篇 |
2018年 | 35篇 |
2017年 | 26篇 |
2016年 | 60篇 |
2015年 | 29篇 |
2014年 | 48篇 |
2013年 | 82篇 |
2012年 | 46篇 |
2011年 | 74篇 |
2010年 | 38篇 |
2009年 | 26篇 |
2008年 | 55篇 |
2007年 | 52篇 |
2006年 | 42篇 |
2005年 | 27篇 |
2004年 | 17篇 |
2003年 | 22篇 |
2002年 | 19篇 |
2001年 | 7篇 |
2000年 | 8篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 7篇 |
1993年 | 5篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1979年 | 2篇 |
1976年 | 1篇 |
1971年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有870条查询结果,搜索用时 15 毫秒
171.
Genetic Structure of a Mimosoid Tree Deprived of Its Seed Disperser, the Spider Monkey 总被引:1,自引:0,他引:1
Abstract: To assess the genetic consequences for a Neotropical tree of the loss of its main seed disperser, we compared the genetic structure of Inga ingoides in a site where the spider monkey (Ateles paniscus) was abundant and a site where it had been eliminated by subsistence hunting. Gene flow should be reduced in the site where the spider monkey is absent, and there should be a corresponding subpopulation differentiation of seedlings within the spatial range of the movements of these primates in the absence of between-site differences in allelic frequencies. At the microhabitat ( family) scale, seedlings growing under parent plants should be genetically more related in the absence of the spider monkey than in its presence. Subpopulation differentiation was smaller where the spider monkey was present ( four loci, FST = 0.011) than where it was absent ( four loci, FST = 0.053) for the first year of study, but not for the second year (three loci, FST = 0.005 vs. 0.003). The number of alleles in common among seedlings growing under parent plants was smaller in the presence of the spider monkey than in its absence, showing family genetic structure in the first generation for both years of study ( Mann-Whitney, z = −2.17, p = 0.03 and z = −2.72, p = 0.006 for 1996 and 1997, respectively). This family genetic structure in the first generation should accelerate the development of population genetic structure. Development of genetic structure might result in demographic changes, one of which would be a fitness reduction if the species were self-incompatible, as suggested for Inga by available evidence. Large birds and mammals are the main targets of subsistence hunting in the Neotropics. Extinction of seed-dispersing frugivores may result in pronounced changes in the demographic and genetic structure of tree species in Neotropical forests. 相似文献
172.
Jorge Luis Frangi 《生态毒理学报》2000,22(2):75-78
为这片世界最南端的森林提出的一个主要森林管理和家具木材生产方案的可能影响,已经引起广泛关注.对这些原始森林的未来所给予的注意,突出说明了环境保护/生物多样性保护与经济效益之间的冲突.火地岛的公共当局和居民处在一个能指定他们合意的生活方式与环境质量的地位,而且能参与旨在以适合于其社会、经济和生态的条件和期望的方式确保可持续性的决策. 相似文献
173.
Francisco M. Baena-Moreno Mónica Rodríguez-Galán Fernando Vega Luis F. Vilches Benito Navarrete 《International Journal of Green Energy》2019,16(5):401-412
Biomethane production through biogas upgrading is a promising renewable energy for some industries which could be part of the equilibrium needed with fossil fuels consumption to achieve a sustainable society. This paper presents a comprehensive list of biogas upgrading technologies focused on carbon dioxide removal as well as recent advances reported by researcher with wide expertise in this topic. Additionally, an extensive costs–performance comparison among the technologies studied is discussed. Among the different alternatives, chemical scrubbing stood out to achieve high biomethane purities while cryogenic technologies proved to be effective against methane losses. Regarding the different costs, water scrubbing and membrane separation seem to be the most affordable techniques. 相似文献
174.
Benyei Petra Cohen Marianne Gresillon Etienne Angles Stéphane Araque-Jiménez Eduardo Alonso-Roldán María Espadas-Tormo Isidro 《Regional Environmental Change》2018,18(2):595-605
Regional Environmental Change - In the context of climate change, concern is raising about the negative effects of some pruning waste management practices. On the one hand, burning of pruning... 相似文献
175.
Team trust is gaining attention in research and practice due to its benefits for team performance, yet clarity about the intricacies of its measurement is needed. Therefore, we meta-analyzed 118 studies (N = 7,738) to untangle the role of measurement features by investigating the degree to which they influence the trust–performance relationship. Results showed that the trust–performance relationship is contingent upon time lag and source of measurement. Specifically, cross-sectional and single-source studies produced higher effect sizes than time-lagged and different-source studies. In contrast, the moderating roles of conceptualization–operationalization alignment and referent of trust measures were not supported. Post hoc analyses revealed that affective trust is more strongly related to global, versus specific team outcomes, and that mixed-referent items are particularly effective within intact teams, whereas the trust–performance relationship is constrained when direct consensus items are used within ad hoc teams. Furthermore, we provided a critical review that highlights the importance of composites, multilevel forces, and item content and wording. Finally, we clarified key gaps in the literature, calling for research where needed. This review serves as a bridge between conceptualization and measurement and lays the groundwork for advancing knowledge of team trust. 相似文献
176.
The modern sociological literature on disasters highlights the fact that many of the ideas about human behaviour in disasters which were long considered as valid, are wrong. The main discovery is based on the fact that situations of crisis increase people's moral principles and capability of response. This paper illustrates some of these ideas, in a case study of a village which was struck by a natural disaster in the north of Granada (Spain) in 1986. The population's attitude revealed a huge potential of resources that were underestimated by professionals of disaster management. The analysis shows that it is necessary to bring civil protection systems and the population's capability of response into close harmony. 相似文献
177.
Wendlandt Amézaga Teodoro Rafael Camarena José Luis Celaya Figueroa Roberto Garduño Realivazquez Karla Alejandra 《Environment, Development and Sustainability》2022,24(1):765-788
Environment, Development and Sustainability - Current trends such as imminent overpopulation and the take-make-waste economic model are largely responsible for the planet’s dire situation.... 相似文献
178.
Luis Antonio Bojórquez-Tapia Peter F. Ffolliott D. Phillip Guertin 《Environmental management》1990,14(3):317-324
The current Mexican environmental law provides the legal basis for comprehensive land-use planning. Under the law, development
of natural ecosystems must combine goals, policies, and practices towards the sustainable use of natural resources and the
protection of biological diversity. Thus, ecosystem manipulation must be able to counter fragmentation of natural ecosystems
and isolation of natural reserves, while providing for human needs. Assessment of the potential of natural ecosystems and
management impacts are required. Multiple-resource simulation is an assessment and land-use planning tool that permits managers
and decision makers to comply with the law, providing a flexible, user-oriented system that can meet the needs of managers,
conservationists, and researchers. A multiple-resource model and an example of how it can be applied to meet planning needs
is presented for discussion. 相似文献
179.
Duncan J Golicher Robert B O'Hara Lorena Ruíz-Montoya Luis Cayuela 《Ecological applications》2006,16(1):202-212
Bayesian methods incorporate prior knowledge into a statistical analysis. This prior knowledge is usually restricted to assumptions regarding the form of probability distributions of the parameters of interest, leaving their values to be determined mainly through the data. Here we show how a Bayesian approach can be applied to the problem of drawing inference regarding species abundance distributions and comparing diversity indices between sites. The classic log series and the lognormal models of relative- abundance distribution are apparently quite different in form. The first is a sampling distribution while the other is a model of abundance of the underlying population. Bayesian methods help unite these two models in a common framework. Markov chain Monte Carlo simulation can be used to fit both distributions as small hierarchical models with shared common assumptions. Sampling error can be assumed to follow a Poisson distribution. Species not found in a sample, but suspected to be present in the region or community of interest, can be given zero abundance. This not only simplifies the process of model fitting, but also provides a convenient way of calculating confidence intervals for diversity indices. The method is especially useful when a comparison of species diversity between sites with different sample sizes is the key motivation behind the research. We illustrate the potential of the approach using data on fruit-feeding butterflies in southern Mexico. We conclude that, once all assumptions have been made transparent, a single data set may provide support for the belief that diversity is negatively affected by anthropogenic forest disturbance. Bayesian methods help to apply theory regarding the distribution of abundance in ecological communities to applied conservation. 相似文献
180.