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371.
Susan Bambrick 《Resources Policy》1979,5(2):150
The Sydney Showground was the scene for a major international exhibition of mining and exploration equipment - AIMEX '79. In conjunction with this was held the Australian Mining Symposium, organized by Thomson Publications (Aust) Pty Ltd, and sponsored by the Australian Mining Industry Council. The symposium, entitled ‘Projections for the future in mining and exploration— political, economic and global’, included a number of papers of wide interest, with two or three papers of much narrower technical appeal. Proceedings of the symposium are to be published. Australian Mining Symposium, Sydney, February 1979. 相似文献
372.
Susan Fuertsch Fanok Ellen E. Wohl 《Journal of the American Water Resources Association》1997,33(5):1091-1102
ABSTRACT: Gaging stations established in 1895 at Millville, West Virginia and in 1882 at Harpers Ferry, West Virginia record flows ranging from a maximum of 6,509 m3s-1 to a minimum of 2 m3s-1. Historical and botanical indicators were used to extend the systematic flood record of the Shenandoah River for a study reach approximately 7.5-km long. The long systematic record at the site provides a good opportunity to assess the accuracy of these sources of paleoflood information. Habitation of the area by settlers of European descent began in 1733, and historical flood records extend from 1748. Qualitative historical records from different sources were compared to yield the most complete flood history. The correlation between the various sources was extremely high. Botanical flood evidence preserved as adventitious sprouts, tree scars, and ring anomalies were documented in 37 trees. A flood chronology established from these data extended from 1896 to 1955. Botanical indicators provided an accurate, although incomplete, flood chronology. The ability to determine accurate flood stages from paleohydrologic indicators varied. Historical data yielded relatively accurate stages to within 1–2 m; only minimum values of flood stage could be obtained from botanical indicators. These results illustrate some of the strengths and weaknesses of paleohydrologic investigations in the eastern United States. 相似文献
373.
Over the last decade the Great Smoky Mountains National Park (GSMNP) has experienced a tremendous increase in visitation, especially in backcountry camping. In 1976 there were an estimated 117,500 backcountry visitor nights, with a peak of 16,865 visitor nights in April. The high use season extends from March to October. Visitation tends to be concentrated in certain sections of the park and at specific sites. The Appalachian Trail, which includes about 8 percent of the maintained trail mileage, carried 32 percent of the visitor nights in 1976.Campsite disturbance is also concentrated in specific sites and sections of the park. Maximum camping disturbance per km of maintained trail was 3,400 m2 for the sites on the Appalachian Trail. Shelter sites have more visitation per site and more total disturbance per site than open campsites, but shelters tend to have less intensive disturbance, such as bare soil, because they concentrate trampling impacts. Visitation levels were strongly correlated with disturbances such as bare soil at open campsites. Visitation was significantly correlated to the number of firepits at shelter sites but not to other types of disturbance. Regressions indicate that for each additional visitor night at a site (annual average), one can expect an additional 9 m2 of total disturbance and 1 m2of bare soil. The distance of a site from the nearest road was not significantly correlated with damage or visitation. Elevation was correlated to visitation levels, especially in the case of the shelters. More legal sites and large illegal sites are in mesic forest types. Illegal camping accounted for 10 percent of the total camping disturbance.The data imply that the suggested removal of shelters will require redistribution of visitor use or replacement developments, such as tent platforms, in order to mitigate damage. Zone camping is a possible alternative but presents difficulties because campers may concentrate in certain plant communities and topographic positions. 相似文献
374.
Gerald J. Bakus William G. Stillwell Susan M. Latter Margaret C. Wallerstein 《Environmental management》1982,6(6):493-504
The two major processes of decision making, behavioral interactions and decision analysis, are discussed. Comparisons are made between the Delphi and NGT methods of behavioral interaction. Three different types of decision analysis are compared, including the Goals Achievement Matrix, Concordance Analysis, and the Simple Multi-Attribute Rating Technique. Decision making problems characteristic of environmental studies are reviewed. A method of decision making that combines the best qualities of other methods is suggested. The overall purpose of this paper is to make the technical knowledge of decision making useful to environmentalists, businessmen, citizens, and politicians, and to improve the process of policy making in environmental studies. 相似文献
375.
Susan Coldicutt 《The Environmentalist》1999,18(4):251-261
Environmental knowing includes the very many bodies of formal theory which have some relevance to the environment, as well as the knowing which comes from experience in the environment. This knowing can be seen as informing action both conceptually and instrumentally. This paper presents a multidisciplinary and transdisciplinary approach which can inter-relate these many knowings in a way which is relevant to and contingent on definition of particular environmental problems. This problem-focused approach involves application of a set of questions which are implied by a taxonomy of ignorance. The paper shows how the approach can inter-relate knowings as diverse as Taoism and energy-efficiency standards, with the purpose of informating environmental action. 相似文献
376.
Susan Bambrick 《Resources Policy》1978,4(4):279-286
The development of Australia's North-West Shelf gasfield is the largest single private venture yet undertaken in Australia, with expenditure of around A$3000 million. Gas will be exported (primarily to Japan), and there will be local sales, at present confined to the state of Western Australia. Annual revenue is estimated to be A$743 million (in 1977 prices) over the life of the project, with annual tax and royalties rising to A$330 million once loans are repaid. The net effect on Australia's balance of payments is positive in most years. The project's apparent feasibility has provided an impetus to further offshore exploration in the West, with A$400 million now committed. 相似文献
377.
Susan Bambrick 《Resources Policy》1980,6(2):166-178
Commodity export competitiveness is influenced by prices, costs, physical attributes of commodities, supply reliability and transportation. In the case of Australia, factors affecting such considerations include government export controls, environmental requirements, aboriginal rights and trade union attitudes. The author focuses on export control and the marketing of individual commodities, and emphasizes two issues of importance for the future - further processing before export and the future for long-term contracts. 相似文献
378.
Many of todays agricultural landscapes once held vast amounts of wetland habitat for waterbirds and other wildlife. Successful restoration of these landscapes relies on access to accurate maps of the wetlands that remain. We used C-band (5.6-cm-wavelength), HH-polarized radar remote sensing (RADARSAT) at a 38° incidence angle (8-m resolution) to map the distribution of winter shorebird (Charadriiformes) habitat on agricultural lands in the Willamette Valley of western Oregon. We acquired imagery on three dates (10 December 1999, 27 January 2000, and 15 March 2000) and simultaneously collected ground reference data to classify radar signatures and evaluate map accuracy of four habitat classes: (1) wet with 50% vegetation (considered optimal shorebird habitat), (2) wet with > 50% vegetation, (3) dry with 50% vegetation, and (4) dry with > 50% vegetation. Overall accuracy varied from 45 to 60% among the three images, but the accuracy of focal class 1 was greater, ranging from 72 to 80%. Class 4 coverage was stable and dominated maps (40% of mapped study area) for all three dates, while class 3 coverage decreased slightly throughout the study period. Among wet classes, class 1 was most abundant (30% coverage) in December and January, decreasing in March by 15%. Conversely, class 2 increased dramatically from January to March, likely due to transition from class 1 as vegetation grew. This approach was successful in detecting optimal habitat for shorebirds on agricultural lands. For modest classification schemes, radar remote sensing is a valuable option for wetland mapping in areas where cloud cover is persistent.
Also, Department of Fisheries and Wildlife, Oregon State University, Corvallis, Oregon 97331, USA 相似文献
379.
Red light running is a frequent cause of motor vehicle crashes and injuries. A primary countermeasure for red light running crashes is police traffic enforcement. In recent years, many police agencies have begun using automated red light cameras as a supplement to conventional enforcement methods. The present study reviewed and evaluated available evidence in the international literature regarding the effectiveness of cameras to reduce both red light violations and crashes. Camera enforcement generally reduces violations by an estimated 40-50%. In terms of crash effects, most studies contain methodological flaws that, to varying degrees, either overestimate (failure to adjust for regression to the mean) or underestimate (comparison with nearby signalized intersections affected by cameras) crash effects. Mindful of these limitations, the research generally indicates that camera enforcement can significantly reduce injury crashes at signalized intersections, in particular right-angle injury crashes. Most studies reported increases in rear-end crashes following camera installation. Taken together the studies indicate that, overall, injury crashes, including rear-end collisions, were reduced by 25-30% as a result of camera enforcement. 相似文献
380.
Susan Carr 《Journal of Agricultural and Environmental Ethics》2002,15(1):31-38
In February 2000, the EuropeanCommission adopted a Communication on theprecautionary principle. This states how theCommission intends to apply the principle andestablishes guidelines for its application. Thedocument is intended to inform discussions oninternational agreements. In particular, itprovides a defense of European Union (EU)precautionary policies in case of tradedisputes, for example, in case the EU isaccused of imposing unfair trade barriers onexports of genetically-modified (GM) productsfrom the United States under the rules of theWorld Trade Organisation. In the communication,the Commission emphasizes the scientificaspects of the precautionary principle, perhapspartly to counter claims from US officials thatthe EU's reluctance to accept GM imports is notbased on science but is politically-motivated.However, a principle is by definition a moralguide to behavior. In other words, it is anethic. The precautionary principle should beviewed as a complement to science, to beinvoked when a lack of scientific evidencemeans that outcomes are uncertain. Anyinterpretation of this principle needs to placeat least as much emphasis on its ethical andvalue-based aspects as on its scientificjustification. The Commission's interpretationrisks undermining the painstaking progress madeamong European Union member states inresponding to public concern about GM crops andfood by adopting increased precaution. Thispaper explores the balance between thescientific and ethical/value-based aspects ofthe precautionary principle as set out in theCommission's communication, to make the casethat it is the ethical and value-based aspectsrather than the scientific aspects of theguidelines that need strengthening. 相似文献