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371.
Roland Weber Stefan Gonser Jutta Köhler Wolfgang Körner Christine Herold Roland Haag Margit Krapp Ludwig Peichl 《Environmental science and pollution research international》2018,25(17):16344-16354
In the 1980s, it was demonstrated that semi-volatile organic compounds (SVOCs) like polychlorinated biphenyls (PCBs) accumulate in plant leaves. Plants are at the base of the food chain, and therefore a starting point for transfer of PCBs to animals and related human exposure. For two decades, the Environment Agency of the German federal state of Bavaria (LfU) has been operating long-term monitoring stations to measure the impact of organic air pollutants. Standardized ryegrass, curly kale, and spruce needles are used as bioindicators for the atmospheric entries of PCBs into vegetation. From the end of 1990s to 2009, there was a marked decline in the concentrations of indicator PCBs (i-PCBs) and a minor decline in PCB-TEQ levels. After 2009, the concentrations leveled off. In rural areas, the median concentrations of Σ6 i-PCB in ryegrass and curly kale were about 3 and 4 μg/kg dm in 2000, and have been about 0.5 and 1 μg/kg dm since 2009, respectively. Concentrations in spruce needles fell from 0.9 to 0.4 μg/kg dm. Median PCB-TEQ concentrations in the bioindicator plants ranged from 0.05 to 0.23 ng/kg dm between 2002 and 2009 and from 0.15 to 0.05 ng/kg dm after 2009. Indicator PCB and PCB-TEQ concentrations were several times higher at the urban station in Munich than at the rural areas, reflecting the emissions from in-use PCB stocks in the building sector. The likely reason of the slower decrease of PCB-TEQ compared to i-PCBs is the formation of PCB-126 by dechlorination of industrial PCBs in open applications. 相似文献
372.
Design principles and common pool resource management: an institutional approach to evaluating community management in semi-arid Tanzania 总被引:1,自引:0,他引:1
This paper analyses the role of institutions in the management of common pool resources (CPRs) in semi-arid Tanzania. Common property regimes have often been considered inadequate for the management of CPRs because of the problems of excludability, but they are becoming more widely supported as the way forward to overcome the problems of resource use and degradation in developing countries. A series of design principles for long enduring common property institutions have been proposed by Ostrom, but there is concern that they are not applicable to a wide range of real life situations or that they may be specific to certain types of CPR. Here, we compare these principles to the situation prevailing in 12 villages in six districts in semi-arid Tanzania. Data on management institutions were collected through semi-structured interviews and meetings at district and village level. The combined information was used to make a qualitative assessment of the strength with which each design principle appeared to operate in the management of forest, pasture and water resources. Boundaries, conflict and negotiation in CPR management are of key importance in semi-arid regions. However, the need for flexibility in order to deal with ecological uncertainty means that many management institutions would be considered weak or absent according to the design principle approach. This supports the view that the design principles should not be used as a 'blueprint to be imposed on resource management regimes' rather that they provide a framework for investigating common property regimes with the proviso that, certainly for semi-arid regions, they may highlight where management cannot be explained by institutional theory alone. 相似文献
373.
Lennert-Cody Cleridy E. Maunder Mark N. Román Marlon H. Xu Haikun Minami Mihoko Lopez Jon 《Environmental and Ecological Statistics》2020,27(4):649-664
Environmental and Ecological Statistics - Management of large-scale pelagic fisheries relies heavily on fishery data to provide information on tuna population status because, for widely distributed... 相似文献
374.
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376.
Understanding the evolutionary processes from recent demographic history is especially difficult for interstitial organisms
due to their poorly known natural history. In this study, the genetic variation and population history of the four Ototyphlonemertes (Diesing in Sitz ber Math Nat Kl Akad Wiss Wien 46:413–416, 1863) species were evaluated from samples collected along the Brazilian coast (between 27°31′S and 13°00′W) in 2006. The mitochondrial
region cytochrome c oxidase subunit 3 (COX3) is analyzed to assess the genetic variation of these dioecious species. Although these species have
a sympatric distribution along the coast, our data suggest that their levels of differentiation and their demographic histories
differ sharply. There is strong evidence of gene flow among demes in O. erneba and O. evelinae, and their level of structuring is much lower than for the other two species. Indeed, the COX3 fragment reveals cryptic lineages
in O. lactea and O. parmula. The results seem to contradict the high genetic structuring and low intrapopulational variability expected with the ecological
constriction and habitat discontinuity faced by these organisms, meaning that there might be gene flow among populations or
their dispersal capability has been underestimated. 相似文献
377.
Adjusting the timing of hatching to changing environmental conditions has fitness costs in blue tits
Edward?KluenEmail author Maaike?E.?de?Heij Jon?E.?Brommer 《Behavioral ecology and sociobiology》2011,65(11):2091-2103
After laying the first egg, a bird can, to a certain extent, adjust the hatching date of the brood to environmental conditions.
However, costs of this adjustment have remained largely unexplored. We studied potential costs of hatching delay in a population
of blue tits in southern Finland. We explored the factors underlying hatching delay and investigated the association between
hatching delay, clutch hatchability and female body condition. Finally, we reciprocally cross-fostered a large number of broods
irrespective of their experienced hatching delay to address possible downstream effects of hatching delay on developmental
parameters in offspring. We found that hatching delay was associated with early laying dates and low mean temperatures during
the egg-laying phase. Furthermore, we found evidence that delayed hatching negatively affected the breeding performance. Hatchability
of the clutch was lowered and the breeding female was energetically impaired, resulting in smaller clutch sizes, lower female
body mass at hatching and lowered survival of nestlings reared in nests that had experienced a long hatching delay. In addition,
delayed hatching had a significant negative effect on the body mass of nestlings prior to fledging. However, ultimately we
did not find evidence that delayed hatching affected survival of the breeding female nor recruitment of fledglings in the
local breeding population. Our study demonstrates that environmental conditions during egg laying can have lasting effects
throughout the breeding and nestling phase. Furthermore, our results emphasize the importance of energetic tradeoffs by breeding
females during the early breeding phase to manage reproductive costs. 相似文献
378.
Hansen S Nieboer E Sandanger TM Wilsgaard T Thomassen Y Veyhe AS Odland JØ 《Journal of environmental monitoring : JEM》2011,13(8):2143-2152
The objective of this study was to investigate changes in the levels of toxic and essential elements in maternal blood during pregnancy and subsequently. A subset of 211 pregnant women from the North Norwegian Mother-and-Child Study was included. Blood samples were collected during the 2(nd) trimester (P1) and postpartum (day 3, P2; and 6 weeks, P3) in different regions of northern Norway, and were analyzed for a suite of 10 selected elements. The latter feature three general but distinct concentration patterns across the three collection periods, namely: progressive increase [Group 1: As, Cd (non-smokers only), Mn, Pb and Zn]; V-shaped, with a minimum at P2 [Group 2: Cd (smokers), Hg, Mo and Se]; and downward V, with a maximum at P2 [Group 3: Co and Cu]. These trends are interpreted in the context of underlying metabolic, hematological and physiological changes that occur in mothers, as well the biochemistry and accumulation preferences of these elements within the whole blood compartment and breast milk. Implications for biomonitoring strategies are discussed. In a multivariable analysis of the P1 data, fish consumption was a robust positive predictor for Hg (p < 0.02), As (p < 0.01) and Se (p ≤ 0.001) blood concentrations, multivitamin intake for Se (p < 0.001), and parity for Co (p < 0.002); age reached significance only for Hg (p < 0.001). An inverse association was observed between parity and Hg (p < 0.05). For the other elements, predictor patterns were not evident. 相似文献
379.
Elie Gaget Alison Johnston Diego Pavón-Jordán Aleksi S. Lehikoinen Brett K. Sandercock Alaaeldin Soultan Luka Božič Preben Clausen Koen Devos Cristi Domsa Vitor Encarnação Sándor Faragó Niamh Fitzgerald Teresa Frost Clemence Gaudard Lívia Gosztonyi Fredrik Haas Menno Hornman Tom Langendoen Christina Ieronymidou Leho Luigujõe Włodzimierz Meissner Tibor Mikuska Blas Molina Zuzana Musilová Jean-Yves Paquet Nicky Petkov Danae Portolou Jozef Ridzoň Laimonas Sniauksta Antra Stīpniece Norbert Teufelbauer Johannes Wahl Marco Zenatello Jon E. Brommer 《Conservation biology》2022,36(4):e13877
Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds. 相似文献
380.