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991.
MATTHEW SOMMERVILLE E.J. MILNER‐GULLAND MICHAEL RAHAJAHARISON JULIA P.G. JONES 《Conservation biology》2010,24(6):1488-1498
Abstract: Despite the growing interest in conservation approaches that include payments for environmental services (PES), few evaluations of the influence of such interventions on behaviors of individuals have been conducted. We used self‐reported changes in six legal and illegal forest‐use behaviors to investigate the way in which a PES for biodiversity conservation intervention in Menabe, Madagascar, influenced behavior. Individuals (n =864) from eight intervention communities and five control communities answered questions on their forest‐use behaviors before and after the intervention began, as well as on their reasons for changing and their attitudes to various institutions. The payments had little impact on individuals’ reported decisions to change behaviors, but it had a strong impact on individuals’ attitudes. Payments appeared to legitimize monitoring of behaviors by the implementing nongovernmental organization (NGO), but did not act as a behavioral driver in their own right. Although there were no clear differences between changes in behaviors in the intervention and control communities, the intervention did influence motivations for change. Fear of local forest associations and the implementing NGO were strong motivators for changing behavior in communities with the PES intervention, whereas fear of the national government was the main reason given for change in control communities. Behavioral changes were most stable where fear of local organizations motivated the change. Our results highlight the interactions between different incentives people face when making behavioral decisions and the importance of considering the full range of incentives when designing community‐based PES interventions. 相似文献
992.
We tracked the long-term movements of 70 parrotfishes, surgeonfishes and goatfishes captured inside a small (1.3 km2) marine protected area (MPA: Kealakekua Bay Marine Life Conservation District, Hawaii) by implanting them with small transmitters
and deploying underwater monitoring devices inside the bay and along 100 km of the adjacent west Hawaii coastline. Individual
fish were detected inside Kealakekua Bay for up to 612 days but many were detected for much shorter periods (median = 52 days).
There were species-specific differences in the scale of movements and habitats used, but most fish utilized between 0.2 and
1.6 km of coastline, and individuals of each species showed some degree of diel habitat shift. A wide variety of reef fishes
captured inside the MPA swam back and forth across an MPA boundary intersecting continuous reef (i.e., this boundary was porous
to reef fish movements), but only 1 of 11 species tagged crossed a wide sandy channel inside Kealakekua Bay suggesting that
this feature may function as a natural barrier to movements. Results indicate relatively small MPAs (<2 km of coastline) could
provide effective, long-term protection for multi-species assemblages of reef fishes provided that boundaries are situated
along major habitat breaks (e.g., large sand channels between reefs) that may serve as natural barriers to reef fish movements.
It is crucial that a multi-species approach be used when assessing MPA effectiveness. 相似文献
993.
This paper presents a scan statistic, progressive upper level set (PULSE) scan statistic, for geospatial hotspot detection
and its software implementation. Like ULS, the PULSE scan statistic is based on the arbitrarily shaped scan window and can
be adapted for a network setting. PULSE is a refinement of the upper level set (ULS) scan statistic. Like some other likelihood
based scanning devices, the ULS scan statistic identifies maximum likelihood estimate (MLE) zones that tend to be ‘stringy’
and sprawling. Its search path increases possibility of inclusion of extraneous cells in its MLE zones and, to a smaller extent,
of exclusion of cells that belong to a true hotspot from its MLE zone. The PULSE scan statistic achieves improvement over
the ULS scan statistic in two ways. First, it begins its search for a most likely zone with a large population of candidate
zones obtained by modifying the ULS tree structure and continues its search using a genetic algorithm. Secondly, to reduce
chances of generating an MLE that is excessively stringy and that includes extraneous cells in the MLE zone, PULSE uses cardinality
and compactness of zones along with their likelihoods as the fitness function in the genetic algorithm and uses several pertinent
criteria including evenness of intra-zone cellular response ratios to determine the MLE zone. To reduce computation, Gumbel
distribution of extreme values is used to determine the p-value of the MLE zone. Better results come at the cost of increased processing time. An evaluative performance study is presented. 相似文献
994.
We equipped individual tiger (Galeocerdo cuvier Péron and Lesueur, 1822) and Galapagos (Carcharhinus galapagensis Snodgrass and Heller, 1905) sharks with both acoustic and satellite transmitters to quantify their long-term movements in
the Papahanaumokuakea Marine National Monument (Northwestern Hawaiian Islands). Tiger sharks exhibited two broad patterns
of behavior. Some individuals were detected at French Frigate Shoals (FFS) year round, whereas others visited FFS atoll in
summer to forage on fledging albatross, then swam thousands of kilometers along the Hawaiian chain, or out into open ocean
to the North Pacific transition zone chlorophyll front, before returning to FFS in subsequent years. These patterns suggest
tiger sharks may use cognitive maps to navigate between distant foraging areas. Different patterns of spatial behavior may
arise because cognitive maps are built up through individual exploration, and each tiger shark learns a unique combination
of foraging sites. Galapagos shark detections were all associated with FFS, suggesting these sharks may be more resident around
oceanic islands. Both Galapagos and tiger sharks primarily used the mixed layer (<100 m depth) and made occasional deeper
dives through the thermocline down to 680 m. Results show reef-associated sharks utilize a wide variety of habitats ranging
from shallow atoll lagoons to deep reefs and open ocean and may provide important trophic links between these habitats. 相似文献
995.
Lorien Pichegru Peter G. Ryan Robert J. M. Crawford Carl D. van der Lingen David Grémillet 《Marine Biology》2010,157(3):537-544
In variable environments, organisms are bound to track environmental changes if they are to survive. Most marine mammals and
seabirds are colonial, central-place foragers with long-term breeding-site fidelity. When confronted with environmental change,
such species are potentially constrained in their ability to respond to these changes. For example, if environmental conditions
deteriorate within their limited foraging range, long-lived species favour adult survival and abandon their current breeding
effort, which ultimately influences population dynamics. Should poor conditions persist over several seasons, breeding-site
fidelity may force animals to continue breeding in low-quality habitats instead of emigrating towards more profitable grounds.
We assessed the behavioural response of a site-faithful central-place forager, the Cape gannet Morus capensis, endemic to the Benguela upwelling system, to a rapid shift in the distribution and abundance of its preferred prey, small
pelagic shoaling fish. We studied the distribution and the abundance of prey species, and the diet, foraging distribution,
foraging effort, energy requirements, and breeding success of gannets at Malgas Island (South Africa) over four consecutive
breeding seasons. Facing a rapid depletion of preferred food within their foraging range, Cape gannets initially increased
their foraging effort in search of their natural prey. However, as pelagic fish became progressively scarcer, breeding birds
resorted to scavenging readily available discards from a nearby demersal fishery. Their chicks cannot survive on such a diet,
and during our 4-year study, numbers of breeding birds at the colony decreased by 40% and breeding success of the remaining
birds was very low. Such behavioural inflexibility caused numbers of Cape gannets breeding in Namibia to crash by 95% following
over-fishing of pelagic fish in the 1970s. In the context of rapid environmental changes, breeding-site fidelity of long-lived
species may increase the risk of local or even global extinction, rendering these species particularly vulnerable to global
change. 相似文献
996.
Olle Anderbrant Donald S. Matteson C. Rikard Unelius Philip S. Pharazyn Ellen M. Santangelo Fredrik Schlyter Göran Birgersson 《Chemoecology》2010,20(3):179-187
Stereoisomers of 4-methyl-3-heptanol (MH) are pheromone components of several Scolytus bark beetles. The elm bark beetle Scolytus laevis (Coleoptera: Scolytidae) has in previous studies been caught in traps baited with commercial MH containing all four stereoisomers,
but the lure has been considered a weak attractant. In this study, we addressed the question whether stereospecific responses
by S. laevis to stereoisomers of MH might contribute to its niche separation from other sympatric Scolytus species. Using GC–MS, we analyzed extracts of hindguts and abdomens from male and female S. laevis and the sympatric S. triarmatus. We also tested all four MH-stereoisomers individually and in combinations in the field to determine their role for S. laevis. All four stereoisomers were synthesized via a boronic ester method with 1,2-dicyclohexylethanediol as chiral director. In
addition, the (3S,4R)-stereoisomer of MH was prepared through enantioselective, lipase-mediated transesterification of a mixture of the four stereoisomers
of MH. Females of both species contained small amounts of syn-MH, and males contained trace amounts of anti-MH. The anti stereoisomer
(3R,4S)-MH was attractive to male and female S. laevis, whereas the syn stereoisomer (3S,4S)-MH acted as an inhibitor or deterrent and reduced the catch when added to the attractive isomer. The syn isomer is the main
aggregation pheromone component of the larger and sympatric S. scolytus and possibly also of S. triarmatus. The avoidance response of S. laevis to the (3S,4S)-stereoisomer may reduce interspecific competition for host trees. 相似文献
997.
JOCELYN G. MUELLER ISSOUFOU HASSANE BIL ASSANOU† IRO DAN GUIMBO‡ ASTIER M. ALMEDOM§ 《Conservation biology》2010,24(1):140-150
Abstract: There is a pressing need to find both locally and globally relevant tools to measure and compare biodiversity patterns. Traditional ecological knowledge (TEK) is important to biodiversity monitoring, but has a contested role in preliminary biodiversity assessments. We examined rapid participatory rural appraisal (rPRA) (a tool commonly used for local needs assessments) as an alternative to surveys of vascular plants conducted by people with local knowledge. We used rPRA to determine the local-knowledge consensus on the average richness, diversity, and height of local grasses and trees in three habitats surrounding Boumba, Niger, bordering Park-W. We then conducted our own vascular plant surveys to collect information on plant richness, abundance, and structure. Using a qualitative ranking, we compared TEK-based assessments of diversity patterns with our survey-based assessments. The TEK-based assessments matched survey-based assessments on measures of height and density for grasses and trees and tree richness. The two assessments correlated poorly on herb richness and Simpson's D value for both trees and grasses. Plant life form and gender of the participant affected the way diversity patterns were described, which highlights the usefulness of TEK in explaining local realities and indicates limitations of using TEK as a large-scale assessment tool. Our results demonstrate that rPRA can serve to combine local-knowledge inquiry with scientific study at a cost lower than vascular plant surveys and demonstrates a useful blunt tool for preliminary biodiversity assessment. 相似文献
998.
Adrian A. Smith Jocelyn G. Millar Lawrence M. Hanks Andrew V. Suarez 《Behavioral ecology and sociobiology》2012,66(9):1267-1276
Eusociality is characterized by a reproductive division of labor, wherein workers respond to the presence of reproductive individuals by refraining from reproduction themselves and restricting the reproductive efforts of others. Our understanding of how eusociality is maintained therefore depends on characterizing the mechanism by which workers detect the presence of a reproductive. Variations in cuticular hydrocarbons correspond to changes in reproductive ability in ants, and experimental studies are beginning to reveal the function of hydrocarbons as signals. In this study, we compare the cuticular hydrocarbon profiles of dominant and reproductive workers and queens of the ant Odontomachus brunneus with profiles of non-reproductive workers. Using split/reunification tests we document the existence of worker policing in both queenless and queenright colonies; supernumerary reproductives were treated aggressively by nestmates. Finally, we induce aggression and replicate queen-like submissive nestmate responses by supplementing the hydrocarbon profile of workers with (Z)-9-nonacosene, a compound that was significantly more abundant on the cuticles of reproductives. In three bioassays, we compare this manipulation to various control manipulations of the hydrocarbon profile and demonstrate that workers gauge the reproductive activity of nestmates through changes in their cuticular hydrocarbon profiles. 相似文献
999.
In the present study, the hypothesis that marine nudibranch mollusks harbor symbiotic bacteria was tested using analyses of fatty acids as biochemical markers and transmission electron microscopy of the tissues of Dendrodoris nigra (Gastropoda/Opisthobranchia/Nudibranchia). An aberrant level of the odd-numbered carbon chain and branched fatty acids, iso- and anteiso- that are specific for bacteria, was detected in the nudibranch tissues. Their amounts in the notum exceeded significantly that in the viscera. Rod-shaped gram-negative bacteria were revealed in the epithelial cells of the notum and the mantle edge as well as in the adjoining glycocalix. These bacteria were enclosed in secondary vacuoles in the epithelial cells. The consequent stages of inoculation of the bacteria into the cytoplasm of epithelial cells, from adhesion to the apical surface to invagination of the cell membrane and formation of the vacuole with an enclosed bacterium, were observed. The presence of dividing bacteria suggests that the epithelium includes a renewable, dividing population of symbiotic bacteria. No bacteria were detected in the gonads and the digestive system. Probable functions of these symbiotic bacteria such as involvement in protection or defense from predators and environmental impacts as well as their nutritional role in the nudibranch are discussed. 相似文献
1000.
G. Verreydt I. Van Keer J. Bronders L. Diels P. Vanderauwera 《Environmental geochemistry and health》2012,34(6):725-736
A site- and receptor-specific risk management strategy for groundwater pollution based on the measurement of contaminant mass flux is proposed. The approach is useful and compatible with the demands formulated in the European Water Framework Directive, its Groundwater Daughter Directive and the regulations applicable in the EU member states. The proposed CMF method focuses on the following: (1) capture zones, (2) the location of control planes, (3) the definition of the maximum allowed contaminant mass discharge and (4) contaminant mass flux measurements. For every control plane, such a maximum allowed contaminant mass discharge is derived and is crucial for the receptor risk management strategy. The method is demonstrated for a large area of groundwater pollution present in the industrial area of Vilvoorde–Machelen located in Flanders, Belgium. 相似文献