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251.
Sandström P Pahlén TG Edenius L Tømmervik H Hagner O Hemberg L Olsson H Baer K Stenlund T Brandt LG Egberth M 《Ambio》2003,32(8):557-567
When seeking to resolve complex land-management issues, geographical assessment of resources that are in short supply or in dispute can aid the communication of knowledge and the understanding among and between different stakeholders. In this paper, we illustrate how remote sensing and GIS can be used to gather and compile information regarding land-use activities and patterns among reindeer herders and other land users (forestry, mining, tourism, etc) in northern Sweden. The project represents a novel user-oriented effort largely based on the work carried out by the principal end user, i.e. the reindeer herders themselves. The basis for development of land-use plans for reindeer husbandry, was the following: to collect and digitally systemize traditional ecological and landscape knowledge of reindeer habitat use; to integrate this information with results from field inventories and satellite-based vegetation classifications; to map activities of other land users. The resulting land-use plans provide information that can facilitate consultation between the reindeer herders and other stakeholders and can facilitate operational work in reindeer management. This project can serve as a model for participatory involvement and planning, bringing indigenous knowledge and advanced remote-sensing techniques together in an interactive process. 相似文献
252.
Animal behavior is a central part of animal welfare, a keystone in sustainable animal breeding. During domestication, animals have adapted with respect to behavior and an array of other traits. We compared the behavior of junglefowl and White Leghorn layers, selected for egg production (and indirectly for growth). Jungle-fowl had a more active behavior in social, exploratory, anti-predatory, and feeding tests. A genome scan for Quantitative Trait Loci (QTLs) in a junglefowl x White Leghorn intercross revealed several significant or suggestive QTLs for different traits. Some production QTLs coincided with QTLs for behavior, suggesting that pleiotropic effects may be important for the development of domestication phenotypes. One gene has been located, which has a strong effect on the risk of being a victim of feather pecking, a detrimental behavior disorder. Modern genomics paired with analysis of behavior may help in designing more sustainable and robust breeding in the future. 相似文献
253.
K. Pingoud A.-L. Perälä A. Pussinen 《Mitigation and Adaptation Strategies for Global Change》2001,6(2):91-111
The carbon (C) reservoir of wood products in Finnishconstruction and civil engineering was estimated by three inventoriesincluding the years 1980, 1990 and 1995. The inventory method ismainly based on the statistics of Finnish building stock. The use of differentconstruction materials in different parts of buildings is estimated for eachbuilding type. Information collected through building permits includes thematerials of bearing frames and facades. More information about the useof wood products in construction is gathered by many enquiries. The mixof construction materials has changed during each decade. Furthermore, thetimber stocks in construction not subject to permission and in civilengineering (e.g. bridges) were estimated. The C reservoir is calculated onthe basis of dry matter content of wooden construction materials. The timeparameters of a simple exponential decay model and a more detailed Cbalance model of wood products were calibrated to the inventory resultsusing the estimated wood flows to construction as model inputs.According to the inventories the C pool in sawn wood and wood-basedpanels of the Finnish building stock was 8.7 Tg C in 1980, 10.7 Tg C in1990 and 11.5 Tg C in 1995. The mean annual increases, 0.20 Tg Cfrom 1980 to 1990 and 0.15 Tg C from 1990 to 1995, areapproximately 1.3% and 0.8% of the fossil fuel C emissions in Finlandduring the same periods. When also taking into account construction notsubject to permission and civil engineering works, the estimated C stock ofwood products in Finland was 16.5 Tg C in 1995, which is about 3.3 MgC per capita and approximately 2.4% of the C reservoir in Finnish forestbiomass. The total C reservoir of wood products (excluding wood wasteand paper products) coming from Finnish forests might be as much as 7%of the standing biomass if exported wood products are also included. Theaverage lifetime of sawn wood in Finnish construction is less than 40 years. 相似文献
254.
Christina Skarpe Per Arild Aarrestad Harry P. Andreassen Shivcharn S. Dhillion Thatayaone Dimakatso Johan T. du Toit Duncan J. Halley Hkan Hytteborn Shimane Makhabu Moses Mari Wilson Marokane Gaseitsiwe Masunga Ditshoswane Modise Stein R. Moe Rapelang Mojaphoko David Mosugelo Sekgowa Motsumi Gosiame Neo-Mahupeleng Mpho Ramotadima Lucas Rutina Lettie Sechele Thato B. Sejoe Sigbjrn Stokke Jon E. Swenson Cyril Taolo Mark Van 《Ambio-人类环境杂志》2004,33(6):254-260
博茨瓦纳北部及其毗邻地区分布着世界上最大的非洲象种群(Loxodonta africana),而在100年前,由于过度捕猎,大象的种群数量极为稀少. 相似文献
255.
Marianne E. Bechmann Per Stlnacke Sigrun H. Kvrn 《Agriculture, ecosystems & environment》2007,120(2-4):117-128
Simple risk assessment tools for agricultural phosphorus (P) losses, like the P index, have been developed in the U.S.A. and in some European countries. Despite its popularity, there have been surprisingly few studies, which try to test the index close to the field scale. For Norway, the P index approach comprises the risk related to both the source of P (soil P status, amount of fertilizer and manure as well as method of application, plant P release by freezing and P balance) and the risk related to transport of P (erosion, flooding, surface runoff, contributing distance, modified connectivity, soil profile, subsurface drainage). In this paper, we have applied the Norwegian P index to farmer fields within a small agricultural catchment, the Skuterud catchment (450 ha), in southeastern Norway. The Norwegian P index was tested for two agricultural fields (0.3–0.4 ha) and nine subcatchments (6–65 ha). Total P concentrations in runoff from the 11 study areas were measured during the year from May 2001 to April 2002. Results from the testing showed that the Norwegian P index described 66% of the variation in measured relative total P concentration for fields and subcatchments included in this study. Additionally, the P index was able to detect fields and subcatchments with the highest measured P concentrations. Results also showed that the source factor contributed most to the variation between fields and hence were important for the identification of high-risk areas in Skuterud catchment. It was found that the soil P status described 66% of the variation in the source factor. Among the transport variables, it was found that both erosion risk and contributing distance had an important influence on the transport factor. Overall, the study illustrated the potential of the P index to detect areas with the highest risk of P loss. 相似文献
256.
Per Mickwitz Matti Melanen Ulla Rosenstrm Jyri Seppl 《Journal of Cleaner Production》2006,14(18):1603-1611
Eco-efficiency emerged in the 1990s as a measure of “the efficiency with which ecological resources are used to meet human needs.” Eco-efficiency indicators as tools for regional sustainability policy were demonstrated in a Life-Environment project, ECOREG, in the Finnish region of Kymenlaakso. A participatory approach was utilised to produce indicators that are relevant for regional decision-makers and that will actually be used. The approach established a system through which decision-makers are able to monitor changes using several economic-environmental ratio indicators, and at the same time obtain information on the social progress taking place in the region. In the future, there will be a need for an ongoing dialogue among the different actors in the region in order to ensure that the indicators are indeed used to promote sustainable development. 相似文献
257.
258.
259.
Theory predicts that, with conflicting selection pressures mediated by mutualists and antagonists, alternative reproductive strategies can be maintained by negative frequency-dependent selection if it results in rare-morph advantage. We combined field experiments and surveys of natural populations to determine whether selection on floral display is frequency dependent in the self-incompatible herb Primula farinosa, which is polymorphic for inflorescence height and occurs in a short-scaped and a long-scaped morph. Among short-scaped plants, both pollination success, quantified as initiation of fruits and seeds, and seed predation were positively correlated with the relative frequency of the long-scaped morph. The relative strength of these effects and the direction of the resulting frequency-dependent selection on scape morph varied among years and populations. The results suggest that both mutualists and antagonists may mediate frequency-dependent selection and that frequency dependence may vary from positive to negative with rare-morph advantage, depending on the relative strength of these interactions. 相似文献
260.
Peery MZ Beissinger SR House RF Bérubé M Hall LA Sellas A Palsbøll PJ 《Ecology》2008,89(10):2746-2759
Source-sink dynamics have been suggested to characterize the population structure of many species, but the prevalence of source-sink systems in nature is uncertain because of inherent challenges in estimating migration rates among populations. Migration rates are often difficult to estimate directly with demographic methods, and indirect genetic methods are subject to a variety of assumptions that are difficult to meet or to apply to evolutionary timescales. Furthermore, such methods cannot be rigorously applied to high-gene-flow species. Here, we employ genetic parentage assignments in conjunction with demographic simulations to infer the level of immigration into a putative sink population. We use individual-based demographic models to estimate expected distributions of parent-offspring dyads under competing sink and closed-population models. By comparing the actual number of parent-offspring dyads (identified from multilocus genetic profiles) in a random sample of individuals taken from a population to expectations under these two contrasting demographic models, it is possible to estimate the rate of immigration and test hypotheses related to the role of immigration on population processes on an ecological timescale. The difference in the expected number of parent-offspring dyads between the two population models was greatest when immigration into the sink population was high, indicating that unlike traditional population genetic inference models, the highest degree of statistical power is achieved for the approach presented here when migration rates are high. We used the proposed genetic parentage approach to demonstrate that a threatened population of Marbled Murrelets (Braclhyrarmphus marmotus) appears to be supplemented by a low level of immigration (approximately 2-6% annually) from other populations. 相似文献