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61.
Markets are increasingly being incorporated into many aspects of daily life and are becoming an important part of the conservation solution space. Although market-based solutions to environmental problems can result in improvements to conservation, a body of social science research highlights how markets may also have unforeseen consequences by crowding out or displacing 3 key types of behaviors potentially relevant to conservation, including people's willingness to engage in collective action and civic duty; tolerance for inflicting harm on others (third-party externalities); and desire for equity. Better understanding of the contexts and mechanisms through which this crowding out occurs and whether specific market-based instruments are more prone to different types of crowding out will be crucial to developing novel conservation initiatives that can reduce or prevent crowding out.  相似文献   
62.
Phosphorus enhances eutrophication of fresh water bodies. This study was conducted to determine the influence of tillage and P placement on P losses in runoff water from a somewhat poorly drained soil (Woodson silt loam [fine, smectitic, thermic Abruptic Argiaquoll], 1.0-1.5% slope) in a grain sorghum [Sorghum bicolor (L.) Moenchl-soybean [Glycine mar (L.) Merr] rotation. Chisel-disk-field cultivate (ChT), ridge-till (RT), and no-till (NT) in combination with 0 kg P ha(-1) or 24 kg P ha(-1) broadcast or knifed (applied prior to planting grain sorghum) were studied. Runoff volume and losses of sediment and P were summed over the growing season. Significant interactions between tillage and P placement for soluble P losses were found. For example, soluble P loss in 1999 for NT-broadcast in grain sorghum was 358 g ha(-1); significantly greater than 31 g ha(-1) for NT-knife or 23 g ha(-1) for NT-check. Similar results were found for RT but no such differences were found for ChT. Bioavailable P losses were generally highest with broadcast P placement and for NT and RT. Total P losses were significantly higher at 959 g ha(-1) with broadcast P on grain sorghum in 1998, compared with 521 g ha(-1) for the check and 659 g ha(-1) for the knifed P applications. Total P losses in 1999 for soybeans were only 18 g ha(-1) for NT, which was significantly lower than 75 g ha(-1) for ChT and 66 g ha(-1) for RT. The results indicate that broadcast P applications on RT and NT will increase P losses, but the influence of tillage was not consistent.  相似文献   
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64.
Fatty acid analyses are emerging as a powerful technique to probe trophic interactions between organisms. In this paper, the application of both this procedure and gonad index (GI) determination on two populations (intertidal and subtidal) of the echinoid Psammechinus miliaris is reported. The investigation spanned the 3-month spawning period of Scottish west coast populations. In both populations a progressive decrease in the GI was found, coupled with an increasing maturity stage (from mature to spent). Sexual maturation and decrease in GI was synchronous between the two populations. In conjunction, there were distinct changes in gonad biochemistry. Differences in the fatty acid composition of the gonad reflected the changes in sexual maturation. Mature males and females had significant differences in the fatty acid composition of their gonads, whereas post-spawned individuals showed no gender differences. Male urchins had higher levels of polyunsaturated fatty acids (PUFAs) compared to females, and there was a dramatic reduction in the fatty acids 22:6(n−3) and 20:5(n−3) with increasing maturity stage. Using multivariate statistical techniques, these changes in the fatty acid composition of the sea urchin gonad were linked to habitat related diet differences combined with gender differences. These changes in the fatty acid signatures clearly reflect the dual function of the gonad as both a nutrient store and a reproductive organ.  相似文献   
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66.
The purpose of this paper is to review the literature to characterize infiltration rates from landfill liners to support groundwater modeling efforts. The focus of this investigation was on collecting studies that describe the performance of liners 'as installed' or 'as operated'. This document reviews the state of the science and practice on the infiltration rate through compacted clay liner (CCL) for 149 sites and geosynthetic clay liner (GCL) for 1 site. In addition, it reviews the leakage rate through geomembrane (GM) liners and composite liners for 259 sites. For compacted clay liners (CCL), there was limited information on infiltration rates (i.e., only 9 sites reported infiltration rates.), thus, it was difficult to develop a national distribution. The field hydraulic conductivities for natural clay liners range from 1 x 10(-9) cm s(-1) to 1 x 10(-4) cm s(-1), with an average of 6.5 x 10(-8) cm s(-1). There was limited information on geosynthetic clay liner. For composite lined and geomembrane systems, the leak detection system flow rates were utilized. The average monthly flow rate for composite liners ranged from 0-32 lphd for geomembrane and GCL systems to 0 to 1410 lphd for geomembrane and CCL systems. The increased infiltration for the geomembrane and CCL system may be attributed to consolidation water from the clay.  相似文献   
67.
ABSTRACT: A series of reforms in the water industry in Australia has created a demand from the industry and regulators for objective methodologies to evaluate incremental changes in the customer service standards. In this paper, the use of choice modeling for estimating implicit prices associated with urban water supply attributes is explored. Results from multinomial logit (MNL) and random parameters logit (RPL) models show that increases in annual water bills and the frequency of future interruptions were the most important attributes. Implicit price confidence intervals based on the best models suggest that people are willing to pay positive amounts to achieve a water supply that is less frequently interrupted. The provision of alternative water supplies during an interruption and notification of the interruption were found to be unimportant to respondents. Choice modeling proved to be a useful technique and provided the industry and regulators with additional information for standard setting.  相似文献   
68.
The inductively coupled plasma (ICP), when employed as an excitation source in optical atomic emission spec.troscopy (AES), is finding widespread utilization for single and multielement inorganic trace analysis of pollutants. The recent availability of commercial ICP‐AES instrument systems has stimulated applications for the determination of metals and metalloids in diverse materials ranging from air particulates and fly ash to industrial effluents, sewage, and hard, soft, and saline waters.

The capabilities and limitations of ICP‐AES for applications in air and water pollution analysis are reviewed, and a number of recent examples presented.  相似文献   
69.
Seasonal changes of respiratory metabolism and biochemical composition were studied in Actinia equina L. (Cnidaria: Anthozoa) collected in 1982 and 1983 from two shore locations in Spain. Changes of metabolic activity follow closely those of biochemical constituents, particularly carbohydrates and lipids, showing maxima in late fall and spring. Weight dependence, established according to the exponential equation y=a xb (x=weight), results in virtually isometric relationships for proteins, total lipids and sugars but not glycogen. Allometry for this last compound represents a reduction in glycogen level in connection with size decrease; this weight effect declines when glycogen levels rise, both in field and laboratory fed anemones, thus suggesting a stronger influence of food availability on storage in small anemones.  相似文献   
70.
Marine plastic pollution has emerged as one of the most pressing environmental challenges of our time. Although there has been a surge in global investment for implementing interventions to mitigate plastic pollution, there has been little attention given to the cost of these interventions. We developed a decision support framework to identify the economic, social, and ecological costs and benefits of plastic pollution interventions for different sectors and stakeholders. We calculated net cost as a function of six cost and benefit categories with the following equation: cost of implementing an intervention (direct, indirect, and nonmonetary costs) minus recovered costs and benefits (monetary and nonmonetary) produced by the interventions. We applied our framework to two quantitative case studies (a solid waste management plan and a trash interceptor) and four comparative case studies, evaluating the costs of beach cleanups and waste-to-energy plants in various contexts, to identify factors that influence the costs of plastic pollution interventions. The socioeconomic context of implementation, the spatial scale of implementation, and the time scale of evaluation all influence costs and the distribution of costs across stakeholders. Our framework provides an approach to estimate and compare the costs of a range of interventions across sociopolitical and economic contexts.  相似文献   
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