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991.
In spite of widespread support from most member countries’ societies for European Union policy, including support for the
sustainable development idea, in many EU countries the levels of acceptance of new environmental protection programmes have
been and, in particular in new member states, still are considerably low. The experience of the countries which were the first
to implement union directives show that they cannot be effectively applied without widespread public participation. The goal
of this study was, using the example of Poland, to assess public acceptance of the expansion of nature conservation in the
context of sustainable development principles and to discover whether existing nature governance should be modified when establishing
new protected areas. The increase in protected areas in Poland has become a hotbed of numerous conflicts. In spite of the
generally favourable attitudes to nature which Polish people generally have, Natura 2000 is perceived as an unnecessary additional
conservation tool. Both local authorities and communities residing in the Natura areas think that the programme is a hindrance,
rather than a help in the economic development of municipalities or regions, as was initially supposed. This lack of acceptance
results from many factors, mainly social, historic and economic. The implications of these findings for current approach to
the nature governance in Poland are discussed. 相似文献
992.
In recent years, altered forest conditions, climate change, and the increasing numbers of homes built in fire prone areas
has meant that wildfires are affecting more people. An important part of minimizing the potential negative impacts of wildfire
is engaging homeowners in mitigating the fire hazard on their land. It is therefore important to understand what makes homeowners
more or less willing to take action. The research presented here comes from a study that interviewed a total of 198 homeowners
in six communities in the western United States about the activities they had undertaken to mitigate their fire risk, the
factors that contributed to their decisions, and their future intentions. The current paper reports on findings from the first
half of the longitudinal study, after 3 years we will return to interview the current homeowner on the same properties to
assess maintenance actions and facilitating and limiting factors. Overall we found a body of individuals who understand the
fire risk, are taking numerous mitigation actions, and think that these actions have reduced their risk. These homeowners
typically did not expect the government to do it for them: they wanted information about what to do and, in some cases, assistance
with the work, but saw taking care of their property primarily as their responsibility. Responses also show that key information
sources and motivating factors vary by location and that it is not inherently necessary to have relationships between community
members to create defensible space. 相似文献
993.
The current article looks into the development of an organic market segment in Norway by following organic milk and the controversies
that have emerged in the trail of this morally infused artefact. In particular focus is the reformatting of organic milk around
the turn of the millennium and the following attempts by various actors to make this product more accessible for a larger
group of consumers. The approach favored in this undertaking is actor-network theory (ANT), which stresses the distributed
nature of moral agency and that human and non-human elements of actor networks should be given equal attention when accounting
for societal practices. Economic narratives such as the sovereign consumer are also used to shed light on the constitution
of organic milk as a moral object and the positioning of this product relative to products stemming from conventional agriculture. 相似文献
994.
995.
Carolyn?M.?KurleEmail author Elizabeth?H.?Sinclair Ann?E.?Edwards Carolyn?J.?Gudmundson 《Marine Biology》2011,158(11):2389-2404
To test the hypothesis that stable isotope ratios from marine organisms vary, the δ15N and δ13C values from fish and squid collected in Alaskan waters were measured across years (1997, 2000, and 2005), seasons, geographic
locations, and different size/age classes, and between muscle tissue and whole animals. Temporal, geographic, and ontogenetic
differences in stable isotope ratios ranged from 0.5–2.5‰ (δ15N) to 0.5–2.0‰ (δ13C). Twenty-one comparisons of stable isotope values between whole organisms and muscle tissue revealed only four small differences
each for δ15N and δ13C, making costly and space prohibitive collection of whole animals unnecessary. The data from this study indicate that significant
variations of stable isotope values from animals in marine systems necessitates collection of prey and predator tissues from
the same time and place for best interpretation of stable isotope analysis in foraging ecology studies. 相似文献
996.
Gert Everaert Pieter BoetsKoen Lock Sašo D?eroskiPeter L.M. Goethals 《Ecological modelling》2011,222(14):2202-2212
Polder lakes in Flanders are stagnant waters that were flooded by the sea in the past. Several of these systems are colonized by exotic species, but have hardly been studied until present. The aim of the present study was: (1) to assess the influence of exotic macrobenthic species on the outcome of the Multimetric Macroinvertebrate Index Flanders (MMIF) and (2) to use classification trees for evaluating to what extent physical-chemical characteristics affect the presence of exotic species.In total, 27 mollusc and 10 macro-crustacean species were present in the monitored lakes of which respectively five and four were exotic. The exclusion of the exotic species from the MMIF resulted in a significant decline of this ecological index (−0.03 ± 0.04; p = 0.00). This elimination often resulted into a lower ecological water quality class and more samples were classified into the bad and poor ecological water quality classes.Single-target classification trees for Gammarus tigrinus and Potamopyrgus antipodarum were constructed, relating environmental parameters and ecological status (MMIF) to the occurrence of both exotic invasive species. The major advantages of using single-target classification trees are the transparency of the rule sets and the possibility to use relatively small datasets. However, this classification technique only predicts a single-target attribute and the trees of the different species are often hard to integrate and use for water managers. As a solution, a multi-target approach was used in the present study. Exotic molluscs and crustaceans communities were modelled based on environmental parameters and the ecological status (MMIF) using multi-target classification trees. Multi-target classification trees can be used in management planning and investment decisions as they can lead to integrated decisions for the whole set of exotic species and avoid the construction of many models for each individual species. These trees provide general insights concerning the occurrence patterns of individual crustaceans and molluscs in an integrated way. 相似文献
997.
Laaksonen T Adamczyk F Ahola M Möstl E Lessells CK 《Behavioral ecology and sociobiology》2011,65(2):257-264
Female birds might be able to manipulate the parental effort of their male partner through elevated transfer of hormones to
the eggs, since these hormones affect many chick traits that males might use as cues for adjusting the level of their investment.
We experimentally studied whether female pied flycatchers Ficedula hypoleuca could manipulate male investment via yolk androgens. There is much more variation in yolk androgen levels between females
than within clutches, and in order to change the androgen levels of the eggs, we swapped whole clutches between nests. To
estimate the androgen levels of the clutch, we measured the androgen content of a single egg per clutch. Females did not succeed
in manipulating male effort using yolk androgens, since there was no relationship between the division of parental care within
a pair and either original or foster egg androgen levels. One of these relationships should have occurred if females were
manipulating males. The proportion of feeding visits by the male was higher when the male was old (55%) than when he was young
(45%) and females laid eggs with higher androgen levels when mated with a young male. Young males did not exhibit any responses
to yolk androgen levels either, which indicates that females cannot exploit their effort more than that of old males. We suggest
that females may allocate yolk androgens to adjust the growth trajectories of the chicks to poor growing conditions when mated
with young males that are poor providers or occupying a poor territory. 相似文献
998.
The social spider Anelosimus studiosus exhibits a behavioral polymorphism where colony members express either a passive, tolerant behavioral tendency (social) or
an aggressive, intolerant behavioral tendency (asocial). Here we test whether asocial individuals act as colony defenders
by deflecting the suite of foreign (i.e., heterospecific) spider species that commonly exploit multi-female colonies. We (1)
determined whether the phenotypic composition of colonies is associated with foreign spider abundance, (2) tested whether
heterospecific spider abundance and diversity affect colony survival in the field, and (3) performed staged encounters between
groups of A. studiosus and their colony-level predator Agelenopsis emertoni (A. emertoni)to determine whether asocial females exhibit more defensive behavior. We found that larger colonies harbor more foreign spiders,
and the number of asocial colony members was negatively associated with foreign spider abundance. Additionally, colony persistence
was negatively associated with the abundance and diversity of foreign spiders within colonies. In encounters with a colony-level
predator, asocial females were more likely to exhibit escalatory behavior, and this might explain the negative association
between the frequency of asocial females and the presence of foreign spider associates. Together, our results indicate that
foreign spiders are detrimental to colony survival, and that asocial females play a defensive role in multi-female colonies. 相似文献
999.
James?C.?MakinsonEmail author Benjamin?P.?Oldroyd Timothy?M.?Schaerf Wandee?Wattanachaiyingcharoen Madeleine?Beekman 《Behavioral ecology and sociobiology》2011,65(5):945-958
The Red Dwarf honeybee (Apis florea) is one of two basal species in the genus Apis. A. florea differs from the well-studied Western Hive bee (Apis mellifera) in that it nests in the open rather than in cavities. This fundamental difference in nesting biology is likely to have implications
for nest-site selection, the process by which a reproductive swarm selects a new site to live in. In A. mellifera, workers show a series of characteristic behaviors that allow the swarm to select the best nest site possible. Here, we describe
the behavior of individual A. florea workers during the process of nest-site selection and show that it differs from that seen in A. mellifera. We analyzed a total of 1,459 waggle dances performed by 197 scouts in five separate swarms. Our results suggest that two
fundamental aspects of the behavior of A. mellifera scouts—the process of dance decay and the process of repeated nest site evaluation—do not occur in A. florea. We also found that the piping signal used by A. mellifera scouts to signal that a quorum has been reached at the chosen site, is performed by both dancing and non-dancing bees in
A. florea. Thus, the piping signal appears to serve a different purpose in A. florea. Our results illustrate how differences in nesting biology affect the behavior of individual bees during the nest-site selection
process. 相似文献
1000.
Robin?F.?A.?MoritzEmail author H.?Michael?G.?Lattorff Kendall?L.?Crous Randall?H.?Hepburn 《Behavioral ecology and sociobiology》2011,65(4):735-740
Workers of a queenless honeybee colony can requeen the colony by raising a new queen from a young worker brood laid by the
old queen. If this process fails, the colony becomes hopelessly queenless and workers activate their ovaries to lay eggs themselves.
Laying Cape honeybee workers (Apis mellifera capensis) produce female offspring as an additional pathway for requeening. We tested the frequency of successful requeening in ten
hopelessly queenless colonies. DNA genotyping revealed that only 8% of all queens reared in hopelessly queenless colonies
were the offspring of native laying worker offspring. The vast majority of queens resulted from parasitic takeovers by foreign
queens (27%) and invading parasitic workers (19%). This shows that hopelessly queenless colonies typically die due to parasitic
takeovers and that the parasitic laying workers are an important life history strategy more frequently used than in providing
a native queen to rescue the colony. Parasitism by foreign queens, which might enter colonies alone or accompanied by only
a small worker force is much more frequent than previously considered and constitutes an additional life history strategy
in Cape honeybees. 相似文献