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371.
S.I Schwartz D.E Hansen T.C Foin 《Journal of Environmental Economics and Management》1975,2(2):120-134
The premature conversion of agricultural lands to urban use has concerned many persons, especially when urban sprawl results. In an effort to reduce such premature conversion California offers reduced property taxation to landowners who sign a contract to give up development rights to their property for a specified period. The California program is described and the potential economic benefits, measured as the present value of the tax savings, are calculated. Using these values, the conditions under which acceptance of a contract is preferred to nonacceptance are analyzed. The implications of the results for program effectiveness and land use control policy are discussed. 相似文献
372.
Lene Hansen Egon Noe Katrine Højring 《Journal of Agricultural and Environmental Ethics》2006,19(2):147-168
The relationship between agriculture and nature is a central issue in the current agricultural debate. Organic Farming has
ambitions and a special potential in relation to nature. Consideration for nature is part of the guiding principals of organic
farming and many organic farmers are committed to protecting natural qualities. However, the issue of nature, landscape, and
land use is not straightforward. Nature is an ambiguous concept that involves multiple interests and actors reaching far beyond
farmers. The Danish research project Nature Quality in Organic Farming has investigated the relationship between nature and organic farming. This article will focus on an expert workshop held
in connection with the project that investigates the way different actors conceptualize nature. Farmers, scientists, and non-governmental
organizations came together to discuss their experiences of nature and expectations of organic agriculture. From this interaction,
it was clear that nature is a contested notion. Different understandings of nature exist within the three groups and there
is disagreement as to whether emphasis should be given to biological qualities, production values, or experiential and aesthetic
perspectives. This complexity provides a challenge to organic farming as well as to the implementation of nature considerations
in general. It illustrates an underlying battle for the right to define nature and nature quality and essentially decide what
organic farmers should work towards. We argue that successful implementation requires organic farmers to carefully consider
what expectations they wish to meet. Optimally it is dependent on a dialog between stakeholder interest groups that allows
for multivocality and pluralism. 相似文献
373.
Kirsten Hansen 《Journal of Agricultural and Environmental Ethics》2004,17(1):67-76
In this paper I argue that consumerautonomy does not count in favor of thelabeling of genetically modified foods (GMfoods) more than for the labeling of non-GMfoods. Further, reasonable considerationssupport the view that it is non-GM foods ratherthan GM foods that should be labeled. 相似文献
374.
H. Evan Cornfield Vicente L. Lopes 《Journal of the American Water Resources Association》2004,40(2):321-332
ABSTRACT: A process based, distributed runoff erosion model (KINEROS2) was used to examine problems of parameter identification of sediment entrainment equations for small watersheds. Two multipliers were used to reflect the distributed nature of the sediment entrainment parameters: one multiplier for a raindrop induced entrainment parameter, and one multiplier for a flow induced entrainment parameter. The study was conducted in three parts. First, parameter identification was studied for simulated error free data sets where the parameter values were known. Second, the number of data points in the simulated sedigraphs was reduced to reflect the effect of temporal sampling frequency on parameter identification. Finally, event data from a small range‐land watershed were used to examine parameter identifiability when the parameter values are unknown. Results demonstrated that whereas unique multiplier values can be obtained for simulated error free data, unique parameter values could not be obtained for some event data. Unique multiplier values for raindrop induced entrainment and flow induced entrainment were found for events with greater than a two‐year return period (~25 mm) that also had at least 10 mm of rain in ten minutes. It was also found that the three‐minute sampling frequency used for the sediment sampler might be inadequate to identify parameters in some cases. 相似文献
375.
376.
This article discusses the current framework of coastal decision making which tends to exclude participation by individuals and those without a strong institutional representation. A distinction is drawn between institutional and local stakeholders to illustrate weaknesses in the existing decision framework. It is argued that particularly in the coastal environment, the relationship between changes in physical form and changes in social welfare is critical to understanding how decision making may engage more fully with local stakeholders and ultimately improve decision outcomes. A reordering of stakeholder engagement in decision systems at the coast is proposed and a framework is outlined which enhances the capacity of local stakeholders to influence decision making. 相似文献
377.
Amenity Migration and Public Lands: Rise of the Protected Areas 总被引:1,自引:0,他引:1
Environmental Management - Rural amenity migration, or the relocation for quality of life purposes as opposed to monetary enhancement, has been occurring for decades and has been particularly... 相似文献
378.
Robert K Hall Peter Husby Gary Wolinsky Olof Hansen Michiko Mares 《Environmental monitoring and assessment》1998,51(1-2):357-367
The Central Valley of California contains critical habitat for many aquatic and terrestrial biological resources. The purpose of this R-EMAP project was to assess the effects from a highly modified agriculturally dominated landuse area on the aquatic resources of the lower portion of the Central Valley watersheds. The study area is 24,346 mi2 and comprises the Sacramento Valley and San Joaquin Valley watersheds to the 1,000 ft. elevation contour. Populations of interest are man-made conveyances and wadeable natural streams. There are 40,756 miles of streams and constructed conveyances within the Central Valley as designated by RF3 database. Sample sites were selected to represent 14,399 miles of streams and sloughs, and 16,697 miles of constructed conveyances. 相似文献
379.
The general results of material flow analyses for agricultural farms presented in Part I are now specified for three farms in Lower Saxony. For this, the existing material flow net for winter wheat is extended by the crops of winter barley, winter rye, summer barley, rape, sugar beets and potatoes. The assessment is essentially done regarding the impact categories of resource depletion, cumulated energy demand (CED) and emissions to atmosphere. Besides the assessment of single farms or crops, also the comparison, of different agricultural production systems is possible, whereby the choice of the functional unit and the basis of comparison (with reference to input or output) is of major importance. Additionally, as for agricultural means of production, the material flows and emissions resulting from the provision of carbolime — an often employed carbonate fertiliser as for sugar-beet cultivation — are derived completely within this article. Furthermore, sensitivity analyses on the subject of detail intensity of agricultural basic data are presented for the example of machine employment. The material flow nets are regarded as transferable to other farms with similar crop rotation systems, with an appropriate expenditure of information gathering and parameterisation. The complete net can be used as a module within further investigations, e.g. of the industrial processing of food, as a pre-production chain for agricultural resources being part of the production process (winter wheat — mill, brewing barley — brewery, sugar beets — sugar-factory). 相似文献
380.