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Forest restoration at large scales, or landscapes, is an approach that is increasingly relevant to the practice of environmental conservation. However, implementation remains a challenge; poor monitoring and lesson learning lead to similar mistakes being repeated. The World Wildlife Fund (WWF), the global conservation organization, recently took stock of its 10 years of implementation of forest landscape restoration. A significant body of knowledge has emerged from the work of the WWF and its partners in the different countries, which can be of use to the wider conservation community, but for this to happen, lessons need to be systematically collected and disseminated in a coherent manner to the broader conservation and development communities and, importantly, to policy makers. We use this review of the WWF’s experiences and compare and contrast it with other relevant and recent literature to highlight 11 important lessons for future large-scale forest restoration interventions. These lessons are presented using a stepwise approach to the restoration of forested landscapes. We identify the need for long-term commitment and funding, and a concerted and collaborative effort for successful forest landscape restoration. Our review highlights that monitoring impact within landscape-scale forest restoration remains inadequate. We conclude that forest restoration within landscapes is a challenging yet important proposition that has a real but undervalued place in environmental conservation in the twenty-first century. 相似文献
874.
Daniel F. Viana Stefan Gelcich Erendira Aceves-Bueno Becky Twohey Steven D. Gaines 《Conservation biology》2019,33(2):361-368
Small-scale fisheries collectively have a large ecological footprint and are key sources of food security, especially in developing countries. Many of the data-intensive approaches to fishery management are infeasible in these fisheries, but a strategy that has emerged to overcome these challenges is the establishment of territorial user rights for fisheries (TURFs). In this approach, exclusive fishing zones are established for groups of stakeholders, which eliminates the race to fish with other groups. A key challenge, however, is setting the size of TURFs—too large and the number of stakeholders sharing them impedes collective action, and too small and the movement of target fish species in and out of the TURFs effectively removes the community's exclusive access. We assessed the size of 137 TURFs from across the globe relative to this design challenge by applying theoretical models that predict their performance. We estimated that roughly two-thirds of these TURFs were sized ideally to overcome the challenges posed by resource movement and fisher group size. However, for most of the remaining TURFs, all possible sizes were either too small to overcome the resource-movement challenge or too large to overcome the collective action challenge. Our results suggest these fisheries, which target mobile species in densely populated regions, may need additional interventions to be successful. 相似文献
875.
Coupled bio-physical models of larval dispersal predict that the Costa Rica–Panama (CR–PAN) reefs should constitute a demographically
isolated region in the western Caribbean. We tested the hypothesis that CR–PAN coral reef fish populations would be isolated
from Mesoamerican Barrier Reef System (MBRS) populations. To test that, we assessed population genetic structure in bicolor
damselfish (Stegastes partitus) from both regions. Adult fish were genotyped from five reefs in CR–PAN and from four reefs along the MBRS at 12 microsatellite
loci. Between-region F
ST (F
ST = 0.0030, P < 0.005) and exact test (x
2 = 74.34, df = 18, P < 0.0001) results indicated that there is weak but significant genetic differentiation between regions, suggesting some restriction
in connectivity along the Central American coastline, as predicted by bio-oceanographic models. Additionally, there is among-site
genetic structure in the CR–PAN region, relative to the MBRS and between regions, suggesting higher self-recruitment within
CR–PAN. This finding may be explained by differences in habitat characteristics. 相似文献
876.
Marcela Nováková Barbora Vašáková Hana Kutalová Katarina Galeštoková Klára Průšová Petr Šmilauer Radim Šumbera Daniel Frynta 《Behavioral ecology and sociobiology》2010,64(3):371-379
Spiny mice of the genus Acomys (Muridae) represent a very suitable mammalian model for studying factors influencing the secondary sex ratio (SSR). The maternal
effort in these rodents is extremely biased in favour of the prenatal period and, therefore, maternal manipulation of the
SSR is potentially more advantageous. We studied the SSR in four populations/species of spiny mice kept in family groups consisting
of two closely related females, one non-relative male and their descendants. The groups were established from founding animals
aged about 3 months (maturing age) and were allowed to breed freely for several months. Each litter was sexed after birth,
and relevant data were thoroughly recorded. Altogether, data were collected on 1684 litters: 189 of Acomys sp. from Iran, 203 of A. cilicicus, 875 of A. cahirinus, and 417 of A. dimidiatus. We recorded the sex of 4048 newborns of which 1995 were males and 2053 were females. The overall sex ratio was close to
1:1 (49.2%). Generalized linear mixed models and/or generalized linear models were constructed to evaluate the effect of four
life history and eight social variables on the sex ratio. No consistent effects of these variables on the sex ratio were found
and, interestingly, none of the variables associated with maternal life history had any effect on the sex ratio. Three factors
associated with group composition (i.e. the number of immature males, the number of immature females and the number of breeding
females) did have significant effects on the sex ratio, but these effects were not consistent across the studied species.
In conclusion, our evaluation of this large dataset revealed that the sex ratio in spiny mice is surprisingly stable. 相似文献
877.
878.
This study determines the efficiency of polyaluminium chloride application on phytoplankton species as a consequence of five reservoir restorations in the Czech Republic during the years 2005 and 2008, including the first ever large-scale application. Although polyaluminium chloride has been used in water treatment plants across the world, information about its application toward cyanobacterial blooms in nature is poor. Although the application of polyaluminium chloride did not cause any fundamental long-term changes in the composition of phytoplankton species or phosphorus load, instead causing fast and acute removal of the phytoplankton community, it may act as an algicidal compound with fast removal efficiency. All treated water bodies described in our study remained unaffected by cyanobacterial blooms and the hygienic limit for the purposes of recreation was not exceeded in any particular season. This article should serve as notice of the advantages and disadvantages of polyaluminium chloride application, and also warn against the uniform usage of this chemical as a method of reducing phytoplankton species in all types of water bodies where cyanobacteria are present. Moreover, data about the effects on non-target (invertebrates) species and microcystin release from cyanobacterial cells are also mentioned. 相似文献
879.
Julian E. Spallholz PhD L. Mallory Boylan M. Mahmububur Rahman Daniel Katz J. David Robertson A. B. M. Zakaria 《毒物与环境化学》2013,95(2):211-220
Static and dynamic adsorption studies of Co (II) ions have been undertaken at fixed pH and ionic strength taking binary biopolymeric beads of cross-linked calcium alginate and carboxy methylcellulose as biosorbents. The adsorption data were applied to Langmuir and Freundlich isotherm equations and various static parameters were calculated. The dynamic nature of adsorption process was quantified in terms of several kinetic constants such as rate constants for adsorption (K) and Lagergreen rate constant (K ad). The influence of various experimental parameters such as solid-to-liquid ratio, pH, and temperature, the presence of salts and chemical composition of biopolymeric beads were investigated on the adsorption of cobalt ions. 相似文献
880.
Judy S. LaKind Cheston M. Berlin Jr Jennifer L. Stokes Daniel Q. Naiman Ian M. Paul Donald G. Patterson Jr 《毒物与环境化学》2013,95(6):1047-1054
Polybrominated diphenyl ethers (PBDE) are a class of brominated flame retardants with some congeners having the ability to accumulate in body lipids. The incorporation of PBDE in consumer products found primarily in the indoor environment suggests that routes of exposure include inhalation of indoor air and contact with indoor dust. The purpose of this study was to test the hypothesis that lifestyle factors, and in particular the proximity and use of products likely to contain PBDE in the indoor environment, are primarily responsible for levels of PBDE found in human milk. Human milk samples were taken from two populations of lactating women in the same geographic region of the United States: one “typical” of US suburban lifestyle, and the other practicing a traditional Amish lifestyle, which excludes many modern amenities containing PBDE, such as computers and televisions. For a subset of the cohort, persistent organic pesticides and polychlorinated biphenyls (PCB) were also measured in human milk samples. Despite the small number of participants, there is evidence suggestive of Amish women having lower PBDE concentrations in their milk. In addition, the nonsignificant differences in levels of PCBs and pesticides between the two groups of women as compared to the significant differences in levels of PBDE suggest an important route of exposure for PBDE other than diet. Information prepared for study participants is provided to initiate a dialogue on how to best communicate biomonitoring findings to study participants and to the public in general. 相似文献