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804.
Christian Toochi Egbuche Jia’en Zhang Okechukwu Ukaga 《Environment, Development and Sustainability》2009,11(4):905-928
Using institutional appraisal focused groups (FG) and participatory appraisals with Dillman Total Design Method (TDM), this
study examines community interaction with and utilization of wetland resources in Xinhui, Guangdong Province, China. Field
results show high commercial activities and corresponding impacts on coastal environment. Other interacting factors identified
include: legislation and ecosystem management, stakeholders’ participation, international guidelines criteria, and utilization
of mangrove resources in the region. Sensitivity index and community-based natural resources management collaboration comparison
percentile showed significant differences between cumulative distributions of respondents (D = 0.2568, P = 0.078). Likert statement of 11 sensitivity optional indexes in EMS of K–S test at 0.05 level of P = 0.078 also show significant differences in interaction between respondent groups and sensitivity factors. This indicates
a dysfunction between regional environmental management systems and CBNRM in Xinhui coastal district. Considering the high
tourism potential and economic quest of the region, there is the need for coordinated community enlightenment and further
studies on the social, ecological and economic value of wetland resources.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
805.
Dietary, age and trans-generational effects on the fate of organohalogen contaminants in captive sledge dogs in Greenland 总被引:1,自引:0,他引:1
Studies on the fate of organohalogen contaminants (OHCs) in wild top predator mammals in the Arctic have often been a challenge due to important knowledge deficiencies in the life history of the sampled animals. The present study investigated the influence of age, dietary and trans-generational factors on the fate of major lipophilic chlorinated and brominated OHCs in adipose tissue of a potential surrogate captive species for the polar bear (Ursus maritimus), the sledge dog (Canis familiaris) in West Greenland. Adult female sledge dogs (P) and their sexually-mature (F1) and/or pre-weaning pups (F1-MLK) were divided into an exposed group (EXP) fed blubber from a Greenland minke whale (Balaenoptera acutorostrata) and a control group (CON) given commercially available pork fat. Large dietary treatment-related differences in summed and individual congener/compound adipose tissue concentrations of polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB), chlordanes (CHLs) and polychlorinated biphenyls (PCBs) were found between the EXP and CON groups for all the sledge dog cohorts. However, among the F1-MLK, F1 and P dogs in both of the EXP and CON groups, little or no difference existed in PBDE, HCB, CHL and PCB concentrations, suggesting higher state of equilibrium in adipose tissue concentrations from a very early stage of life. In contrast, the distribution pattern (proportions to the summed concentrations) of OHC classes, and the major congeners/compounds constituting those classes, varied on a dietary group- and/or cohort-dependent manner. The present captive sledge dog study demonstrated the importance of the confounding effects of diet composition, mother-pup association (maternal transfer), reproductive status (nursing), and to a lesser extent age in the fate of OHCs in adipose tissue of a large top carnivore mammal. 相似文献
806.
Differences in the way local and regional interest groups perceive Sustainable Forest Management in regions with different forest use histories were studied using Southeastern Finland, the Mauricie in Quebec and Central Labrador in Canada as examples of regions with high, medium and low importance of commercial forestry. We present a conceptual model illustrating the cyclic interaction between the forest, cultural models about forests and forest management. We hypothesized that peoples' perceptions would be influenced by their cultural models about forests and would thus vary amongst regions with different forest use histories and among different interest groups. The weightings of the environmental, economic and social components of sustainability as well as themes important for each of the interest groups were elicited using individual listing of SFM indicators and group work aimed at developing a consensus opinion on a common indicator list. In Southeastern Finland the views of the different groups were polarized along the environment-economy axis, whereas in Central Labrador all groups were environmentally oriented. The social dimension was low overall except among the Metis and the Innu in Labrador. Only environmental groups were similar in all three research regions, the largest differences between regions were found among the forestry professionals in their weightings concerning economy and nature. As the importance of commercial forestry increased, a greater importance of economic issues was expressed whereas the opposite trend was observed for issues regarding nature. Also inter-group differences grew as the importance of commercial forestry increased in the region. Forest management and forest use can be seen as factors strongly influencing peoples' cultural models on forests. 相似文献
807.
Villanger GD Jenssen BM Fjeldberg RR Letcher RJ Muir DC Kirkegaard M Sonne C Dietz R 《Environment international》2011,37(4):694-708
We investigated the multivariate relationships between adipose tissue residue levels of 48 individual organohalogen contaminants (OHCs) and circulating thyroid hormone (TH) levels in polar bears (Ursus maritimus) from East Greenland (1999-2001, n=62), using projection to latent structure (PLS) regression for four groupings of polar bears; subadults (SubA), adult females with cubs (AdF_N), adult females without cubs (AdF_S) and adult males (AdM). In the resulting significant PLS models for SubA, AdF_N and AdF_S, some OHCs were especially important in explaining variations in circulating TH levels: polybrominated diphenylether (PBDE)-99, PBDE-100, PBDE-153, polychlorinated biphenyl (PCB)-52, PCB-118, cis-nonachlor, trans-nonachlor, trichlorobenzene (TCB) and pentachlorobenzene (QCB), and both negative and positive relationships with THs were found. In addition, the models revealed that DDTs had a positive influence on total 3,5,3'-triiodothyronine (TT3) in AdF_S, and that a group of 17 higher chlorinated ortho-PCBs had a positive influence on total 3,5,3',5'-tetraiodothyronine (thyroxine, TT4) in AdF_N. TH levels in AdM seemed less influenced by OHCs because of non-significant PLS models. TH levels were also influenced by biological factors such as age, sex, body size, lipid content of adipose tissue and sampling date. When controlling for biological variables, the major relationships from the PLS models for SubA, AdF_N and AdF_S were found significant in partial correlations. The most important OHCs that influenced TH levels in the significant PLS models may potentially act through similar mechanisms on the hypothalamic-pituitary-thyroid (HPT) axis, suggesting that both combined effects by dose and response addition and perhaps synergistic potentiation may be a possibility in these polar bears. Statistical associations are not evidence per se of biological cause-effect relationships. Still, the results of the present study indicate that OHCs may affect circulating TH levels in East Greenland polar bears, adding to the "weight of evidence" suggesting that OHCs might interfere with thyroid homeostasis in polar bears. 相似文献
808.
A new species has recently invaded coastal dune ecosystems in North West Europe. The native and expansive inland grass, Deschampsia flexuosa, progressively dominating inland heaths, has recently invaded coastal dunes in Denmark, occasionally even as a dominant species.
A total of 222 coastal locations with 5,000 random sample plots have been investigated. These findings are in contrast to
historical records, and D. flexuosa has never been considered belonging to coastal dune ecosystems. The occurrence of the typical inland grass in the coastal
dunes is a strong indication of increase in nutrient level and that human influences may cause a native species to be invasive
in new ecosystems. This could be a radical example of change in species composition due to a long lasting exceedance of critical
load of nitrogen. The investigation also showed a general increase in cover of the most dominant species. 相似文献
809.
Christian Brodhag 《Natural resources forum》2010,34(1):63-70
The importance of sustainable consumption and production in the international agenda has been growing, both because of unsustainable patterns of consumption and production in industrialized countries and because it appears to be a means for meeting the essential needs of developing countries. Adapting Fernand Braudel's model of the three layers of the economy (everyday life, market economy and global capitalism) to the current situation, this paper advocates for differentiated policies, which cannot be limited to those based on the dominant model of a rational legal system dealing with rational consumers. The cultural and collective dimensions of consumption, the social role of conspicuous consumption, the consumption of ecological services outside formal markets, the diversity of approaches to knowledge and rationality, all plead for an overarching approach and diversified policy tools. The paper underlines the need for global regulation processes which involve all stakeholders by focusing on two examples: the international task force on sustainable tourism, and the ISO 26000 standard on social responsibility. 相似文献
810.
Maria H. G. Canteri Agnes P. Scheer Gilvan Wosiacki Christian Ginies Marise Reich Catherine M. C. G. Renard 《Journal of Polymers and the Environment》2010,18(4):593-599
Brazil is the world’s main producer of passion fruit. Previous reports show that passion fruit rinds, an industrial waste,
contain large amounts of pectin. Pectin is a dietary fiber that is widely used in the food industry as a gelling agent and
stabilizer. In this study, the quality and characteristics of pectin extracted from yellow passion fruit rind flour was investigated.
Pectin was extracted from both commercially available and prepared passion fruit peels using nitric acid. Once extracted,
the pectin was evaluated for its molecular characteristics and chemical composition as well as for the apparent and reduced
viscosity of the gel. Prepared (blanched) rind flour yielded 203.4 g kg−1 of pectin, which contained a uronic acid content of 681 mg g−1, a degree of esterification of 80, a degree of methylation of 80, a reduced viscosity of 6.8 dL g−1 and an apparent viscosity of 13.4 cP. The results suggest a clear influence of the raw material on it’s the resultant characteristics
of the pectin. In addition, our results show that therheological properties and molar characteristics of pectin were negatively
affected when the rind flours were subjected to high temperatures. Pectin methyl esterase activity was detected in the freeze-dried,
unblanched raw material. Extensive efforts have been directed towards minimizing waste and the reported results show that
high quality pectin can be obtained from passion fruit rinds, an industrial waste product of passion fruit processing. 相似文献