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821.
Hans Schreier Sandra Brown George Kennedy Pravakar B. Shah 《Environmental management》1991,15(6):815-822
A GIS-based land evaluation model was developed to determine the food, feed, and fuelwood sufficiency of all districts in
Nepal. Resource surpluses or deficits were calculated for each district for 1981, the year for which the national land resource
data were available. Of the three resources, feed supplies were found to be the most critical. Feed deficits occurred in 57%
of all districts in 1981, while food and fuelwood deficits occurred in less than 10% of all districts. Different scenarios
were carried out for the year 2000 to estimate the magnitude of future resource deficits, assuming resource use and yields
in Nepal remain constant in the face of growing population and livestock numbers. Linking resource data with spreadsheet and
GIS systems provides a new way to understand and evaluate resources at the district and national levels. To more fully capture
the usefulness of this approach, information on rates of change in productivity and land use is needed. 相似文献
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Degradation and mobility of the surfactants linear alkylbenzene sulfonate (LAS) and nonylphenol (NP) were investigated in a lysimeter study using a sandy loam soil and 45-cm soil columns. Anaerobically digested sewage sludge was incorporated in the top-15-cm soil layer to an initial content of 38 mg LAS and 0.56 mg NP kg(-1) dry wt., respectively. Spring barley (Hordeum vulgare L.) was sown onto the columns. The lysimeters were placed outdoors and therefore received natural precipitation, but were also irrigated to a total amount of water equivalent to 700 mm of precipitation. Leachate and soil samples from three soil layers were collected continuously during a growth period of 110 d. Leachate samples and soil extracts were concentrated by solid-phase extraction (SPE) and analyzed using high performance liquid chromatography (HPLC) with fluorescence detection. The concentrations in the top-15-cm soil layer declined to 25 and 45% of the initial contents for LAS and NP, respectively, within the first 10 d of the study. At the end of the study, less than 1% LAS was left, while the NP content was below the detection limit. Assuming first-order degradation kinetics, half-lives of 20 and 37 d were estimated for LAS and NP, respectively. The surfactants were not measured in leachate samples in concentrations above the analytical detection limits of 4.0 and 0.5 microg L(-1) for LAS and NP, respectively. In addition, neither LAS nor NP were measured in concentrations above the detection limits of 150 and 50 microg kg(-1) dry wt., respectively, in soil layers below the 15 cm of sludge incorporation, indicating negligible downward transport of the surfactants in the lysimeters. 相似文献
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Ione M. Smith Ken J. Hall Les M. Lavkulich Hans Schreier 《Journal of the American Water Resources Association》2007,43(6):1455-1467
Abstract: Effects of agricultural intensification and a naturally occurring landslide of asbestos material upon water and sediment quality in a transboundary watershed were investigated. The water and sediments of the Sumas River watershed were analyzed for copper (Cu), zinc (Zn), chromium (Cr), and nickel (Ni) concentrations in 1993/1994 and 2003/2004 and differences within sites over time were examined. Based upon a review of the literature, Cu and Zn were used as indicators of agricultural impacts while Cr and Ni were used as indicators of impacts from an asbestos landslide. Animal unit equivalents (AUEs) were calculated on a per area basis as an indicator of livestock density using detailed statistical census data. Whatman #42 filtered metals, bioavailable metals, and sediment‐bound metals (in the <63 μm fraction) were determined at 22 sites along the mainstem and tributaries, including two reference sites. Temperature, pH, and dissolved organic carbon (DOC) were also measured. The bioavailable metal fraction was determined using the diffusive gradient thin film technique (DGT). Sediment‐bound results were compared with British Columbia’s Interim Sediment Quality Guidelines (ISQGs) and Severe Effects Levels (SELs). A Wilcoxon signed rank test was used to determine if the concentrations of metals changed significantly within sites between 1993/1994 and 2003/2004. Spearman rank correlation analysis was used to determine relationships between trace metals, water quality parameters, and AUEs/hectare. The results indicate that Cu and Zn levels in sediments increased significantly to concentrations above the ISQGs of 35.7 mg/kg and 123 mg/kg, respectively from 1993/1994 to 2003/2004 in streams, where associated land use was dominated by intensive agriculture. Higher AUEs/hectare were significantly correlated with greater bioavailable levels of Zn as well as higher sediment‐bound Zn concentrations. Neither Cu nor Cr were detected by the DGTs on any of the sampling occasions. The Cr and Ni sediment concentrations were highest in Swift Creek, the headwater tributary affected by the natural landslide of asbestos material, and decreased in the Sumas River downstream from the point of input. Cr and Ni concentrations have increased in the mid‐region of the Sumas River since 1993/1994, suggesting downstream movement of the asbestos material over time. DGT results indicated that bioavailable Zn is significantly positively correlated to sediment‐bound Zn and livestock density, and bioavailable Ni is significantly correlated to sediment‐bound Ni. 相似文献
828.
Barbara Skorupinski Heike Baranzke Hans Werner Ingensiep Marc Meinhardt 《Journal of Agricultural and Environmental Ethics》2007,20(1):37-52
This paper focuses on experiences from a case study dealing with the Swiss type of a consensus conference called “PubliForum”
concerning “Genetic Technology and Nutrition” (1999). Societal and ethical aspects of genetically modified food meanwhile
can be seen as prototypes of topics depending on the involvement of the public through a participatory process. The important
role of the lay perspective in this field seems to be accepted in practice. Nevertheless, there is still some theoretical
controversy about the necessity and democratic legitimacy of participatory processes in general, and especially about those
dealing with technological or environmental problems (sustainable development) concerning society. From an ethical point of
view, a lot of heterogeneous problems concerning contents and procedures of public participation can be pointed out, not only
on the theoretical level but also in practice, e.g., concerning the communication process between laypersons and experts.
The intention of our paper is to give hints and to clarify criteria that support the communication process leading to a dialog
of autonomous citizens and which especially consider ethical aspects in the field. One important result is that there must
be an orientation for all members of a consensus conference having clear rules and knowing their different roles that support
transparency, credibility, and fairness of the whole procedure and a “good product”: a substantial final document or citizens’
report.
This paper presents results of the project Ethical Bio-TA Tools as funded by the European Commission, DG Research, under FP5,
Quality of Life Programme. 相似文献
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