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101.
Compassionate conservation focuses on 4 tenets: first, do no harm; individuals matter; inclusivity of individual animals; and peaceful coexistence between humans and animals. Recently, compassionate conservation has been promoted as an alternative to conventional conservation philosophy. We believe examples presented by compassionate conservationists are deliberately or arbitrarily chosen to focus on mammals; inherently not compassionate; and offer ineffective conservation solutions. Compassionate conservation arbitrarily focuses on charismatic species, notably large predators and megaherbivores. The philosophy is not compassionate when it leaves invasive predators in the environment to cause harm to vastly more individuals of native species or uses the fear of harm by apex predators to terrorize mesopredators. Hindering the control of exotic species (megafauna, predators) in situ will not improve the conservation condition of the majority of biodiversity. The positions taken by so-called compassionate conservationists on particular species and on conservation actions could be extended to hinder other forms of conservation, including translocations, conservation fencing, and fertility control. Animal welfare is incredibly important to conservation, but ironically compassionate conservation does not offer the best welfare outcomes to animals and is often ineffective in achieving conservation goals. Consequently, compassionate conservation may threaten public and governmental support for conservation because of the limited understanding of conservation problems by the general public.  相似文献   
102.
Poaching is rapidly extirpating African forest elephants (Loxodonta cyclotis) from most of their historical range, leaving vast areas of elephant‐free tropical forest. Elephants are ecological engineers that create and maintain forest habitat; thus, their loss will have large consequences for the composition and structure of Afrotropical forests. Through a comprehensive literature review, we evaluated the roles of forest elephants in seed dispersal, nutrient recycling, and herbivory and physical damage to predict the cascading ecological effects of their population declines. Loss of seed dispersal by elephants will favor tree species dispersed abiotically and by smaller dispersal agents, and tree species composition will depend on the downstream effects of changes in elephant nutrient cycling and browsing. Loss of trampling and herbivory of seedlings and saplings will result in high tree density with release from browsing pressures. Diminished seed dispersal by elephants and high stem density are likely to reduce the recruitment of large trees and thus increase homogeneity of forest structure and decrease carbon stocks. The loss of ecological services by forest elephants likely means Central African forests will be more like Neotropical forests, from which megafauna were extirpated thousands of years ago. Without intervention, as much as 96% of Central African forests will have modified species composition and structure as elephants are compressed into remaining protected areas. Stopping elephant poaching is an urgent first step to mitigating these effects, but long‐term conservation will require land‐use planning that incorporates elephant habitat into forested landscapes that are being rapidly transformed by industrial agriculture and logging.  相似文献   
103.
Fire is used as a management tool for biodiversity conservation worldwide. A common objective is to avoid population extinctions due to inappropriate fire regimes. However, in many ecosystems, it is unclear what mix of fire histories will achieve this goal. We determined the optimal fire history of a given area for biological conservation with a method that links tools from 3 fields of research: species distribution modeling, composite indices of biodiversity, and decision science. We based our case study on extensive field surveys of birds, reptiles, and mammals in fire‐prone semi‐arid Australia. First, we developed statistical models of species’ responses to fire history. Second, we determined the optimal allocation of successional states in a given area, based on the geometric mean of species relative abundance. Finally, we showed how conservation targets based on this index can be incorporated into a decision‐making framework for fire management. Pyrodiversity per se did not necessarily promote vertebrate biodiversity. Maximizing pyrodiversity by having an even allocation of successional states did not maximize the geometric mean abundance of bird species. Older vegetation was disproportionately important for the conservation of birds, reptiles, and small mammals. Because our method defines fire management objectives based on the habitat requirements of multiple species in the community, it could be used widely to maximize biodiversity in fire‐prone ecosystems. Historiales de Incendios Óptimos para la Conservación de la Biodiversidad  相似文献   
104.
In some species, sperm is stored within the female reproductive tract for months to years, and yet remains viable to fertilize eggs and produce offspring. Female red-sided garter snakes store sperm for over 7 months of winter dormancy. In previous work, we demonstrated that these stored sperm account for an average of 25 % paternity of a litter when the female mates with a male at spring emergence. Here, we tested whether last-male sperm precedence was prevalent when a female mates with two males during the spring. On average, paternity was shared equally among the first (P1 proportion of paternity of the first male to mate) and second males (P2) to mate in the spring, and stored sperm (Pss), but the variance in paternity was high. Thus, last male sperm precedence may diminish when a female has more than two mates. Male size did not affect paternity, but, as the interval between matings increased, P1 increased at the expense of Pss. Interestingly, as the second spring male’s copulation duration increased, P1 also increased at the expense of P2. This result suggests that female influence over sperm and/or copulatory plug transfer during matings may also affect which male fathers her offspring in response to coercive matings as we assisted females to mate for their second mating. Finally, all females were spring “virgins”; consequently, sperm stored from autumn matings (and/or previous spring matings) remain competitive even when faced with two rivals in sperm competition and is likely the driver of the evolution of sperm longevity.  相似文献   
105.
106.
Universities considering integrating an environmental management system (EMS) have numerous decisions to consider. Should they pursue a formal certified model or an informal uncertified one? If informal is appropriate, which framework best meets their needs? Which environmental interactions are most important to manage? Are there any other sector-specific considerations? This article discusses six different campus EMS frameworks, three different categories of drivers, and the six unique features of a campus EMS, and offers suggestions on when each framework is best applied. The frameworks considered are from: ISO 14001; Higher Education 21 (UK); the EMS Self-Assessment Checklist (USA); the Auditing Instrument for Sustainability in Higher Education (Netherlands); the Osnabrück University model (Germany) and the Sustainable University model (Mexico). This article also draws upon the empirical experiences of Dalhousie University in Halifax, Canada.  相似文献   
107.
Contaminants remaining onsite after regulatory‐approved environmental remediation operations are complete represent continued risk to human health and the environment. Many sites require continued management efforts to: (1) protect the integrity of the engineered remedy/control, (2) limit the exposure of individuals to residual contamination by limiting reuse activities, (3) maintain ready access to accurate records/information, and (4) protect against vulnerabilities from intentional threats/actions. This article presents performance information from selected case studies to provide insight into various management approaches employed for addressing the risks associated with residual contaminants. The case studies involve sites remediated within the U.S. Comprehensive Environmental Response, Compensation, and Liability Act framework and illustrate two prevailing management approaches for addressing the risks. Sacrifice zones are sites that are purposefully isolated to prevent human access onto the property. Reuse sites provide limited access for specific use. © 2008 Wiley Periodicals, Inc.  相似文献   
108.
The relative abundance of chaetodontid and pomacentrid fishes in 8 habitats, ranging in depth from 0.5 to 17 m, was determined by visual counting of free-swimming fish in the field. Habitat widths and overlaps were determined using weighting factors, developed by Colwell and Futuyma (1971), which account for the different degree of uniqueness of each habitat. The average habitat widths and the average habitat overlaps were greater for the chaetodontids than the pomacentrids. This was due, in part, to the greater use of habitat structure by the pomacentrids, and it is hypothesized that this is because they are the more vulnerable to predation. The juveniles and adults reached peak abundance in different habitats for at least some of the species, and this may further reduce the habitat-overlap values for adults of some pairs of species. It is clear, however, that the ability of the species in these families to coexist is largely due to factors operating within habitats rather than to a large degree of habitat specialization.  相似文献   
109.
110.
Analytic webs support the synthesis of ecological data sets   总被引:1,自引:0,他引:1  
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