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241.
To achieve a safe and reliable drinking water supply, water producers need to manage a large range of risks regarding both water quality and quantity. A risk management approach where risks are systematically identified and handled in a preventive manner is promoted by the World Health Organization and supported by researchers and drinking water experts worldwide. Risk assessment is an important part of such a management approach, and a variety of tools for risk assessment are described in the literature. There is, however, little knowledge of how drinking water risk assessment is performed in practice, including which tools that are actually used. This study investigates the use of risk assessment tools, and the approach to risk management, on a local level in the Swedish water sector. It is based on interviews with key persons from a targeted selection of water producers. We find that the application of tools as well as the approach to risk assessment and management differs considerably between the water producers. The tools most frequently used are mainly the ones promoted or required by Swedish national organizations. Although many of the water producers have done some kind of risk assessment, most have not implemented a risk management approach. Furthermore, their knowledge of the concepts of risk and risk management is often limited. The largest challenge identified is to prioritize risk assessment, so that it is actually performed and then used as a basis for managing risk in a systematic way. 相似文献
242.
Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape
change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational
needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives
and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for
organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes
ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to
address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models
to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the
role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process
to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify
monitoring data that would both advance ecologic theory and inform management decisions. 相似文献
243.
South Korea’s Civilian Control Zone (CCZ), a relatively untouched area due to tight military oversight since the end of Korean
War, has received considerable attention nationally and internationally for its rich biodiversity. However, the exclusion
of local communities from the process of defining problems and goals and of setting priorities for biodiversity conservation
has halted a series of biodiversity conservation efforts. Through qualitative research, we explored CCZ farmers’ views of
key problems and issues and also the sources of their opposition to the government-initiated conservation approaches. Key
findings include the farmers’ concerns about the impact of conservation restrictions on their access to necessary resources
needed to farm, wildlife impacts on the value of rice and other agricultural goods they produce, and farmers’ strong distrust
of government, the military, and planners, based on their experiences with past conservation processes. The findings regarding
farmers’ perceptions should prove useful for the design of future participatory planning processes for biodiversity conservation
in the CCZ. This case highlights how conservative measures, perceived to be imposed from above—however scientifically valuable—can
be undermined and suggests the value that must be placed on communication among planners and stakeholders. 相似文献
244.
Toward Adaptive Management: The Impacts of Different Management Strategies on Fish Stocks and Fisheries in a Large Regulated Lake 总被引:1,自引:0,他引:1
We applied the adaptive management approach to analyze the demand and feasibility of adaptive management of fish stocks in a large regulated lake, Oulujärvi, in northern Finland. The process consisted of four phases: (1) analysis of the current state of the fisheries system (fishers, related markets and industry, fisheries researches and authorities, related organizations, etc.); (2) analysis of the objectives of different stakeholders; (3) the composition of alternative management strategies and assessment of their impacts; and (4) recommendations for future management. We used catch statistics from the period 1973–1995 to analyze fish stocks and fishing. Fish species involved were brown trout (Salmo trutta L.), whitefish [Coregonus lavaretus (L.) sl.], vendace (Coregonus albula L.); and pikeperch (Stizostedion lucioperca L.). Questionnaires and interviews were applied to ascertain the opinions of different groups of fishermen. Several models and cost–benefit analysis were used to assess the ecological, economic, and social impacts of three alternative management strategies. The results emphasize that when determining stocking levels and fishing regulations, the system should be considered as a whole, and impacts on major fish species and different groups of fishermen should be assessed. The stocking policy and fishing regulations should also be flexible to accommodate changing biotic and societal conditions. The key questions in applying the adaptive management process in Oulujärvi fisheries are how to determine clear objectives for fisheries management, find a fisheries management structure that provides workable interactions between different stakeholders, and arrange cost-effective monitoring. The lessons learned from the Oulujärvi experience and recommendations for fisheries management are relevant to other lakes with conflicting objectives of different stakeholders. 相似文献
245.
Wastewater management in small and medium-sized enterprises representing the chemical and food industries was investigated.
The results showed that wastewater discharged from an ink-production factory was highly contaminated with organic pollutants.
Anaerobic biological treatment followed by chemical coagulation using ferric chloride aided with lime proved to be very effective
and produced an effluent that complied with national regulatory standard for wastewater discharge into public sewage network.
Also, management of wastewater from a confectionery factory representing the food sector was carried out. Aerobic biological
treatment using plastic-packed trickling filter proved to be an effective treatment method. However, application of in-plant
control measures alleviated the requirement for the construction of a wastewater treatment plant. The applied pollution prevention
and cleaner production measures involved good housekeeping, recovery of spent chocolate, modification of floor cleaning and
installation of suction devices for the removal of sugar and starch powders. All improvement measures were documented by cost/benefit
analysis. 相似文献
246.
247.
Awareness of farm animal welfare issues is growing in Canada, as part of a larger food movement. The baseline Canadian standards for farm animal welfare—the Recommended Codes of Practice for the Care and Handling of Farm Animals—are up for revision. The success of these standards will depend in part on perceived legitimacy, which helps determine whether voluntary code systems are adopted, implemented, and accepted by target audiences. In the context of the Codes, legitimacy will also hinge on whether the standards-developers marshal narratives about farm animals that accord with their audiences’ expectations. The aim of this paper is to catalogue factors that influence legitimacy in farm animal welfare standard-setting, including which narratives of animal welfare are emphasized by standard-setters. Drawing upon the example of the baseline Canadian standards, and the National Farm Animal Care Council, the paper will present a theoretical and methodological framework for analyzing legitimacy in the context of animal welfare standards-development and discuss associated policy considerations. 相似文献
248.
Rita JC Gama-Rodrigues EF Gama-Rodrigues AC Polidoro JC Machado RC Baligar VC 《Environmental management》2011,48(1):134-141
Agroforestry systems (AFSs) have an important role in capturing above and below ground soil carbon and play a dominant role
in mitigation of atmospheric CO2. Attempts has been made here to identify soil organic matter fractions in the cacao-AFSs that have different susceptibility
to microbial decomposition and further represent the basis of understanding soil C dynamics. The objective of this study was
to characterize the organic matter density fractions and soil size fractions in soils of two types of cacao agroforestry systems
and to compare with an adjacent natural forest in Bahia, Brazil. The land-use systems studied were: (1) a 30-year-old stand
of natural forest with cacao (cacao cabruca), (2) a 30-year-old stand of cacao with Erythrina glauca as shade trees (cacao + erythrina), and (3) an adjacent natural forest without cacao. Soil samples were collected from 0-10 cm
depth layer in reddish-yellow Oxisols. Soil samples was separated by wet sieving into five fraction-size classes (>2000 μm,
1000–2000 μm, 250–1000 μm, 53–250 μm, and <53 μm). C and N accumulated in to the light (free- and intra-aggregate density
fractions) and heavy fractions of whole soil and soil size fraction were determined. Soil size fraction obtained in cacao
AFS soils consisted mainly (65 %) of mega-aggregates (>2000 μm) mixed with macroaggregates (32–34%), and microaggregates (1–1.3%).
Soil organic carbon (SOC) and total N content increased with increasing soil size fraction in all land-use systems. Organic
C-to-total N ratio was higher in the macroaggregate than in the microaggregate. In general, in natural forest and cacao cabruca
the contribution of C and N in the light and heavy fractions was similar. However, in cacao + erythrina the heavy fraction
was the most common and contributed 67% of C and 63% of N. Finding of this study shows that the majority of C and N in all
three systems studied are found in macroaggregates, particularly in the 250–1000 μm size aggregate class. The heavy fraction
was the most common organic matter fraction in these soils. Thus, in mature cacao AFS on highly weathered soils the main mechanisms
of C stabilization could be the physical protection within macroaggregate structures thereby minimizing the impact of conversion
of forest to cacao AFS. 相似文献
249.
Surindra Suthar 《The Environmentalist》2011,31(1):74-86
Efforts have been made in this study to estimate the current status of earthworm biodiversity in western arid and semiarid lands of India. A total of 513 different locations (rural, urban, and sub-urban localities) covering both arid and semiarid areas were surveyed and 11 earthworm species: Perionyx sansibaricus (Perrier), Amynthas morrisi (Beddard), Metaphire posthuma (Vaillant), Lampito mauritti Kinberg, Dichogaster bolaui (Michaelsen), Octochaetona paliensis (Stephenson), Ramiella bishambari (Stephonson), Ocnerodrilus occidentalis Eisen, Malabaria sp, Allolobophora parva Eisen, and Pontoscolex corethrurus (Müller) belonging to five different families were rerecorded. A few earthworm species, e.g., L. mauritii, M. posthuma, O. occidentalis, and D. bolaui showed their presence in most of the sampling localities, while R. bishambari, Malabaria sp., A. parva, and P. corethrurus were restricted to a particular locality in arid land. Earthworm fauna of this region showed a patchy distribution pattern and the majority of the species were recorded from northern canal-irrigated and central alluvial plain belt (mid to eastern part) of the Thar Desert. Earthworm distribution and species-richness pattern were directly related to the local microclimatic factors and human activities. Thus, results suggested that human activities have been acted as important agency for invasion of earthworm communities in remote areas of western arid land of India. 相似文献
250.
Donald B. Thompson 《Journal of Agricultural and Environmental Ethics》2011,24(2):165-194
The term natural is effective in the marketing of a wide variety of foods. This ambiguous term carries important meaning in Western culture.
To challenge an uncritical understanding of natural with respect to food and to explore the ambiguity of the term, the development of Western ideas of nature is first discussed. Personification and hypostasization of nature are given special emphasis. Leo Marx’s idea of the pastoral
design in literature is then used to explore the meaning of natural as applied to food, emphasizing Marx’s distinction between
a sentimental and a complex pastoral. The latter is applied to natural as a means of collapsing a dichotomy of man and nature to the idea of second nature. From this perspective an understanding of the industrialization of the food system and the importance of local and organic
food are considered. The extent to which processed foods might properly be considered natural is raised and discussed for
several common foods. Although marketing of natural foods might make us think that we consume nature, I suggest that what
is consumed is more appropriately second nature. I suggest that in order to maintain a critical perspective about one’s relationship
to the natural world, everyone should make an attempt to experience the complex pastoral with respect to at least something
that is consumed as food. When nature is understood as second nature in the context of a complex pastoral, the question of
whether a food or ingredient is to be considered natural is replaced by deliberative thought based on our best knowledge and
judgment, and the result will be less constrained by ideology. 相似文献