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481.
Elizabeth Wilson 《Journal of Environmental Planning and Management》1999,42(4):581-598
Capacity for environmental protection is important in developed and transitional countries, but the latter sometimes present a paradox where capacity has been created at the same time as public pressure and awareness has diminished. Slovakia presents a particular paradox, as its new democratic institutions have proved especially fragile. This paper adopts a framework developed by Janicke and Weidner in crossnational studies which implies that the use made of environmental capacity is a function of institutional, informational and structural conditions. By analysing the key features of the Slovakian environmental policy process in the context of these conditions, the paper confirms the utility of the model, and points to the prospects for future policy implementation. 相似文献
482.
Bruce L. Rhoads David Wilson Michael Urban Edwin E. Herricks 《Environmental management》1999,24(3):297-308
The authors' personal experience in watershed planning and decision making in the agricultural Midwest is described to illustrate
how: (1) formalization of the process of community-based management is not sufficient to guarantee that local people will
meaningfully consider scientific information and opinion when making decisions about watersheds, and (2) genuine social interaction
between scientists and nonscientists requires a considerable investment of time and energy on the part of the scientist to
develop personal relationships with nonscientists based on trust and mutual exchange of information. This experience provides
the basis for developing a general conceptual model of the interaction between scientists and nonscientists in community-based
watershed management in the agricultural Midwest.
An important aspect of integrating science effectively into community-based decision making is the need to revise existing
concepts to accommodate place-based contexts. Stream naturalization is introduced as an alternative to stream restoration
and rehabilitation, which are viewed as inappropriate management strategies in human-dominated environments. Stream naturalization
seeks to establish sustainable, morphologically and hydraulically varied, yet dynamically stable fluvial systems that are
capable of supporting healthy, biologically diverse aquatic ecosystems. This general goal is consistent with the types of
stream-management practices emerging from community-based decision making in human-dominated, agricultural landscapes. Further
research on the linkages between geomorphological and ecological dynamics of human-modified agricultural streams over multiple
spatial and temporal scales is needed to provide a sound scientific framework for stream naturalization. 相似文献
483.
Bostrychus sinensis is a facultative air breather that inhabits waters of a wide range of salinities. This study aimed to elucidate whether branchial
and intestinal osmoregulatory acclimation occurred in B. sinensis transferred from 5‰ water through a progressive increase in salinities to seawater. Our results indicate that B. sinensis acted as a hyperosmotic regulator in 5‰ water, but exhibited hypoosmotic hypoionic regulation in seawater. During short-
(1 day) and medium- (10 days) term acclimation to seawater, there were only minor perturbations in plasma osmolality and [Na+], which returned to control levels after 45 days of exposure to seawater. Branchial Na+/K+-ATPase activity was unaffected by 1, 10 or 45 days of exposure to seawater. However, prolonged (45 days) acclimation to seawater
led to a significant increase in Na+/K+-ATPase α-subunit protein abundance. Taken together, these results indicate that there could be changes in the expression
of Na+/K+-ATPase isoforms and/or post-translational modification of Na+/K+-ATPase in the gills of fish exposed to seawater. Immunofluorescence microscopy revealed that acclimation to seawater for
10 days only resulted in no change in branchial Na+/K+-ATPase protein expression, but there were increases in protein expression of cystic fibrosis transmembrane regulator (CFTR)-like
chloride channel and Na+:K+:2Cl− cotransporter (NKCC; probably NKCC1). Indeed, NKCC was undetectable in gills of fish kept in 5‰ water by Western blotting,
but it became weakly detectable in fish exposed to seawater for 10 days and prominently expressed in fish exposed to seawater
for 45 days. Therefore, our results indicate that branchial CFTR-like chloride channel and NKCC1 were the determining factors
in the transition between hyperosmotic regulation and hypoosmotic hypoionic regulation in B. sinensis. Furthermore, the intestine of B. sinensis also served as an important osmoregulatory organ, since there were significant increases in both the activity and protein
abundance of intestinal Na+/K+-ATPase in fish acclimated to seawater for 45 days. The effectiveness of branchial and intestinal osmoregulatory acclimation
in B. sinensis during seawater acclimation led to only a minor increase in plasma osmolality, and thus resulted in relatively unchanged
free amino acid contents in muscle and liver. 相似文献
484.
Birds are commonly sexually promiscuous, which can lead to conflict between the sexes and the evolution of paternity assurance strategies, such as mate guarding. Adaptive explanations for mate guarding have tended to focus on fitness consequences for males, but mate guarding and participation in being guarded is also likely adaptive for females in certain contexts. To better understand the adaptive explanations for mate guarding as well as the observed variation in paternity patterns, it is necessary to explore the relative costs and benefits of guarding (and being guarded) from both the male and female perspective. To investigate these costs and benefits, we conducted an experiment with the Australian zebra finch (Teniopygia guttata) in which we independently varied the perceived opportunity for each member of a captive breeding pair to engage in extra-pair copulation (EPC) solicitation behavior; as an individual’s EPC opportunity increased, the partner’s EPC opportunity remained constant. Our results indicate that, for males, mate guarding intensity increases when their female’s EPC opportunity increases but decreases when their own (i.e., male) EPC opportunity increases. We did not find evidence of flexible female guarding behavior, but we found that females do not evade their partners more as female EPC opportunity increases. 相似文献
485.
486.
Colin J. Garroway Jeff Bowman Paul J. Wilson 《Behavioral ecology and sociobiology》2013,67(1):113-122
Social individuals have organized relationships that affect fitness and so a species' tendency to be social has important implications for its population ecology, gene flow, and its distribution in space and time. We quantitatively examined the social structure of southern flying squirrels (Glaucomys volans) and tested for a role of kinship and prior familiarity in predicting social structure. To quantify social structure, we monitored nest group composition of southern flying squirrels. All squirrels at the study site were marked with passive integrated transponder (PIT) tags and nest cavity entrances were monitored with automated PIT tag recorders for a period of 28 months. Squirrels were genotyped at eight microsatellite loci. Permutation tests of associations suggested that individuals nested with other specific individuals more often than expected by chance. The lagged association rate indicated that relationships were stable and persisted across seasons and years. Multiple summer nest associates came together in winter to form larger nest groups which were likely important for social thermoregulation. A measure of prior familiarity, but not kinship, was related to the proportion of time individuals nested together during winter. We suggest that the evolution of sociality in southern flying squirrels is driven largely by mutually beneficial behaviors related to social thermoregulation although other, as of yet, unidentified mechanisms are needed to explain sociality in the warm season. We hypothesize that minimum group size requirements associated with social thermoregulation could explain the absence of this species in patchy landscapes and aspects of range boundary dynamics near their northern range boundary. 相似文献
487.
David Bierbach Sophie Oster Jonas Jourdan Lenin Arias-Rodriguez Jens Krause Alexander D. M. Wilson Martin Plath 《Behavioral ecology and sociobiology》2014,68(6):935-945
Social organization is often studied through point estimates of individual association or interaction patterns, which does not account for temporal changes in the course of familiarization processes and the establishment of social dominance. Here, we present new insights on short-term temporal dynamics in social organization of mixed-sex groups that have the potential to affect sexual selection patterns. Using the live-bearing Atlantic molly (Poecilia mexicana), a species with pronounced male size polymorphism, we investigated social network dynamics of mixed sex experimental groups consisting of eight females and three different-sized males over a period of 5 days. Analyzing association-based social networks as well as direct measures of spatial proximity, we found that large males tended to monopolize most females, while excluding small- and medium-bodied males from access to females. This effect, however, emerged only gradually over time, and different-sized males had equal access to females on day 1 as well as day 2, though to a lesser extent. In this highly aggressive species with strong social dominance stratifications, the observed temporal dynamics in male-female association patterns may balance the presumed reproductive skew among differentially competitive male phenotypes when social structures are unstable (i.e., when individual turnover rates are moderate to high). Ultimately, our results point toward context-dependent sexual selection arising from temporal shifts in social organization. 相似文献
488.
Macroalgal fields are a feature of the shallow tropical benthos, yet their importance for coral reef fish population dynamics remains poorly understood. The abundance of fish recruits was recorded using underwater visual census at six macroalgal and 11 coral reef sites in the Montebello and Barrow Islands. Surveys identified 6,935 individual recruit fish from 105 species, 54 genera and 20 families. Of these, 1,401 recruits from 48 species, 31 genera and 14 families were observed in macroalgal sites. Sixteen of the 105 recruit species (15.2 %) were observed exclusively at macroalgal sites. Forty-two (87.5 %) of these species have been observed as adults on adjacent coral reefs. Species composition of fish recruits differed significantly between the two habitats. Corallivore, small omnivore and zooplanktivore recruits had significantly higher numbers in the coral sites, while the results clearly demonstrate that juveniles, within the genera Lethrinus and Choerodon, as well as large algal croppers, are predominantly found at macroalgal (74–100 %) rather than coral-dominated sites. High-canopy macroalgae cover was positively correlated with abundance of these taxa, particularly Lethrinids (r 2 = 0.40). This study is the first to highlight the important attributes of tropical macroalgal fields and suggests that they have a similar role to seagrass meadows as essential juvenile habitat, thus warranting greater attention in conservation planning and ecological studies. 相似文献
489.
David M. DeJoy Author Vitae Lindsay J. Della Author Vitae Author Vitae Mark G. Wilson Author Vitae 《Journal of Safety Research》2010,41(2):163-171
Introduction
This study tests a conceptual model that focuses on social exchange in the context of safety management. The model hypothesizes that supportive safety policies and programs should impact both safety climate and organizational commitment. Further, perceived organizational support is predicted to partially mediate both of these relationships.Methods
Study outcomes included traditional outcomes for both organizational commitment (e.g., withdrawal behaviors) as well as safety climate (e.g., self-reported work accidents). Questionnaire responses were obtained from 1,723 employees of a large national retailer.Results
Using structural equation modeling (SEM) techniques, all of the model's hypothesized relationships were statistically significant and in the expected directions. The results are discussed in terms of social exchange in organizations and research on safety climate.Impact on Industry
Maximizing safety is a social-technical enterprise. Expectations related to social exchange and reciprocity figure prominently in creating a positive climate for safety within the organization. 相似文献490.
Enforcement gaps are an especially vexing problem in China due to pervasive "pro-growth" local government priorities, the weak administrative capacity of environmental agencies themselves, and relatively weak levels of societal support for a cleaner environment. This study seeks to examine this problem from the perspective of the local enforcement officials by empirically examining the relationships between these and other influences on their perceptions of enforcement effectiveness. Using samples of enforcement officials from the fast-growing cities of Chengdu, Dalian, and Guangzhou, this study finds that many of the more commonly cited problems related to regulatory enforcement were not as influential in accounting for variations in perceptions of enforcement effectiveness than the current literature might suggest. Moreover, this study also finds that the pattern of influences varies greatly across jurisdictions, with only the officials' belief in the legitimacy of the governments' policies being significant in all three samples. Strong influences on perceptions of enforcement effectiveness in two of the three samples include the environmental values of enforcement officials, their perceptions of organizational capacity for enforcement, and their assessment of government support for environmental protection. Although government support was found to be a strong predictor of enforcement effectiveness in two of the three samples, the influence of societal support had a somewhat mixed and more complicated effect. In addition, this study suggests that further improvements in enforcement effectiveness may be possible by cultivating or selecting enforcement officials with strong environmental values and beliefs in the legitimacy of the government's environmental policy to take charge of enforcement. Because it is generally accepted that local environmental protection bureaus are generally upgrading their organizational capacity for improvement as the result of increasing central government support for environmental protection and institutional restructuring, and because environmental awareness in China is growing, this study suggests that some incremental progress is likely in China's efforts to close the enforcement gap. Unfortunately, such improvements are likely to be masked by the steep trajectory of economic growth, the narrow scope of regulatory control (i.e., with scant attention paid to nonindustrial sources), and the migration of industrial pollution to rural areas. 相似文献