全文获取类型
收费全文 | 127篇 |
免费 | 3篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 9篇 |
废物处理 | 3篇 |
环保管理 | 13篇 |
综合类 | 28篇 |
基础理论 | 31篇 |
环境理论 | 1篇 |
污染及防治 | 37篇 |
评价与监测 | 8篇 |
社会与环境 | 4篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 5篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 2篇 |
2015年 | 2篇 |
2014年 | 4篇 |
2013年 | 7篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 2篇 |
2009年 | 1篇 |
2008年 | 4篇 |
2007年 | 10篇 |
2006年 | 10篇 |
2005年 | 6篇 |
2004年 | 12篇 |
2003年 | 3篇 |
2002年 | 9篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1975年 | 2篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有134条查询结果,搜索用时 171 毫秒
41.
Richard A. Phillips Rona A. R. McGill Deborah A. Dawson Stuart Bearhop 《Marine Biology》2011,158(10):2199-2208
Considerable attention has focused on inter- and intraspecific variation in trophic niches of marine predators. Although this
has revealed evidence for sexual segregation in distribution in some species, few studies have been able to address sex-related
dietary specialisation. Stable isotope analysis of blood cells collected from albatrosses and petrels at South Georgia during
chick-rearing indicated a difference in δ13C, suggesting that females fed to the north of males, only in two species with male-biased sexual size dimorphism; in no species
did sexes differ in trophic level (δ15N). Based on a wider review, significant differences between sexes in isotope signatures were much more common in seabirds
during the pre-laying or breeding than the nonbreeding period, presumably reflecting greater between-sex partitioning of resources
when foraging ranges are more constrained and competition is greater. Sex differences, or their absence, were usually consistent
across successive stages during the pre-laying and breeding periods, but not necessarily year-round nor between populations.
Significant differences in isotope signatures between males and females were extremely rare in monomorphic species, suggesting
a link between sexual size dimorphism and segregation in diet or distribution. Among the Southern Ocean albatrosses, sex differences
in δ13C suggested the underlying mechanism was related to habitat specialisation, whereas in other size-dimorphic taxa (both male-
and female-biased), sex differences were more common in δ15N than δ13C and therefore more consistent with size-mediated competitive exclusion or dietary specialisation. 相似文献
42.
Effects of environmental factors on organochlorine pesticide residues in soils of the Guanting Reservoir area, China 总被引:1,自引:0,他引:1
Wang TY Lu YL Dawson RW Shi YJ Zhang H Xing Y 《Journal of environmental science and health. Part. B》2006,41(3):309-321
Topsoil samples from 56 sites around the Guanting Reservoir, China, were measured for HCH and DDT concentrations. The total soil HCH content (including alpha-, beta-, gamma-, and delta-isomers) in these soil samples ranged from 0 to 7.33 ng x g(-1), with a mean of 0.69 ng x g(-1). These levels were considerably lower than those of the total DDT soil contents (including pp'-DDE, pp'-DDD, op'-DDT, and pp'-DDT), which ranged from 0 to 76.01 ng x g(-1), with a mean of 9.46 ng x g(-1). DDT was also found to be the major pollutant in the soil samples, accounting for approximately 93% of the total organochlorine pesticide (OCP) contents. Several environmental factors including land use, soil texture, soil taxonomy, and microbial biomass were considered to be responsible for the OCP levels observed. The data provide some insight into the effects of environmental conditions such as soil formation, agricultural cultivation, nutrient enrichment, and other anthropogenic activities on the degradation of OCPs in soils. Although the OCP residues currently are below the maximum limits set for use on agricultural land in China, and only rarely would such levels pose significant ecological concern, OCPs are highly persistent in soil and bioaccumulative. The data provided in this study are considered crucial for reservoir remediation, especially since the Guanting Reservoir will serve as one of the main drinking water sources for Beijing in the foreseeable future. 相似文献
43.
A. Guala E. Biroli P. Bassini G. Botta D. Licata G. Di Cara D. Franceschini P. Franceschini 《黑龙江环境通报》2001,21(13):1146-1149
Kyphomelic dysplasia (KD) is a rare autosomal recessive entity characterized by disproportionate dwarfism with shortening and bowing of the limbs, narrow chest, 11 ribs and metaphyseal flaring. Mental development is generally normal. We report the in utero ultrasound appearances and post-mortem radiographic findings of a 22-week-old male fetus suggestive of KD. A review of 19 previously reported patients with KD is also presented. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
44.
Fluctuations and interactions of bacterial activity in sandy beach sediments and overlying waters 总被引:3,自引:0,他引:3
Fluctuations and interactions of the following microbiological variables and sediment properties were investigated on samples from sandy beaches of the Baltic Sea: bacterial number and biomass, net uptake and respiration rate of 14C-glucose (U), concentration of natural free dissolved glucose and fructose, actual uptake rate and turnover time of glucose, sand-grain size and shape, water and organic matter content of the sediment. Spearman rank correlation analysis demonstrated significant relationships between cell number, biomass and actual uptake rate of glucose. The concentration of natural glucose varied with sand-grain shape, and the uptake rates of glucose were inversely correlated with the water content of the sediment. In the overlying water, cell number and/or biomass were significantly correlated with both concentration and uptake rates of glucose. Partial correlation analysis, however, indicates that, in the water overlying the sediment at least one of the standing crop variables (bacterial number or biomass) is independently variable with uptake activity. The sediment bacterial standing crop does not necessarily reflect metabolic activity. Various significant interactions were noted between mainly sediment properties (water content, organic matter content, grain size) and variables in the water above (cell number, biomass, concentration and uptake rates of glucose).Publication No. 206 of the Joint Research Program at Kiel University (Sonderfor-schungsbereich 95 der Deutschen Forschungsgemeinschaft). 相似文献
45.
Olszyk DM Bytnerowicz A Fox CA Kats G Dawson PJ Wolf J 《Environmental pollution (Barking, Essex : 1987)》1987,48(3):197-211
The response of shrubs of Larrea tridentata (DEC) Coville (creosotebush) exposed to sulphur dioxide (SO(2)) was evaluated using in situ plants of the Majove Desert. Larrea was exposed to acute levels of 0.3 to 2.0 microl litre(-1) SO(2) for periods up to 13 days using field chambers or an open-air fumigation system. Plants exposed in the spring exhibited considerable leaf injury (necrosis and defoliation) when exposed to 2.0 microl litre(-1) SO(2), and in the autumn had leaf injury when exposed to >0.4microl litre(-1) SO(2). Injured plants had higher transpiration rates, less negative water pressure potentials, and/or lower photosynthetic rates than control plants. It is likely that Larrea would not be injured by the typically low SO(2) concentrations and dry environmental conditions of the Mojave Desert. However, if injury were to occur, it would be accompanied by changes in plant-water relations and photosynthesis, followed by recovery after the SO(2) stress was removed. 相似文献
46.
Tsunami represents one of the most potentially serious forms of coastal flood risk. Although much is known on the recorded history of tsunamis for given areas of the world, very little information is available on the occurrence of palaeotsunamis during prehistory. This is of fundamental importance in calculating tsunami flood risk for any given coastal area. Given sufficient information on past tsunami activity for a particular coastal area, the numerical calculation of aggregate coastal flood risk (including tsunami) for a coastal area is very difficult to estimate since one needs also to take into account the risk of a tsunami and a storm surge taking place simultaneously during a high tide. Estimates of coastal flood risk also need to consider future changes in relative sea level caused by the combined effects of global climate change and vertical movements of the lithosphere. 相似文献
47.
Pierre-Paul Bitton Russell D. Dawson Courtney L. Ochs 《Behavioral ecology and sociobiology》2008,62(10):1543-1550
Elaborate ornamental plumage has been associated with various measures of individual quality in many species of birds. Male
plumage characteristics, which have been relatively well studied, have been shown to reflect past reproductive investment,
as well as the potential for reproductive investment in the current breeding attempt. In contrast, the signalling functions
of female traits remain largely unexplored. In this study, we investigated the relationship between plumage attributes of
breeding adult tree swallows and past reproductive investment, current reproductive investment and social mate pairing strategy.
Both males and older females possess metallic green to metallic blue iridescent plumage on their dorsal surface, making this
a suitable species for this type of investigation. We did not find any effects of past reproductive investment and success
on the plumage attributes of returning breeders. In contrast, female plumage hue covaried with fledging success, and female
plumage brightness was positively associated with mean clutch egg mass. In addition, we found that social pairs mated assortatively
with respect to plumage brightness. We argue that since plumage characteristics vary with age in both male and female tree
swallows, plumage attributes in this species are indicative of breeding experience and may be honest signals of quality. Positive
assortative pairing could be the result of mutual mate choice or intra-sexual competition for nest sites by both males and
females. 相似文献
48.
Dearing JA Bullock S Costanza R Dawson TP Edwards ME Poppy GM Smith GM 《Environmental management》2012,49(4):767-775
The ‘Perfect Storm’ metaphor describes a combination of events that causes a surprising or dramatic impact. It lends an evolutionary
perspective to how social-ecological interactions change. Thus, we argue that an improved understanding of how social-ecological
systems have evolved up to the present is necessary for the modelling, understanding and anticipation of current and future
social-ecological systems. Here we consider the implications of an evolutionary perspective for designing research approaches.
One desirable approach is the creation of multi-decadal records produced by integrating palaeoenvironmental, instrument and
documentary sources at multiple spatial scales. We also consider the potential for improved analytical and modelling approaches
by developing system dynamical, cellular and agent-based models, observing complex behaviour in social-ecological systems
against which to test systems dynamical theory, and drawing better lessons from history. Alongside these is the need to find
more appropriate ways to communicate complex systems, risk and uncertainty to the public and to policy-makers. 相似文献
49.
Economic Analysis of Summer Fallow Management to Reduce Take-All Disease and N Leaching in a Wheat Crop Rotation 总被引:1,自引:0,他引:1
Stéphane De Cara Florence Jacquet Arnaud Reynaud Gaël Goulevant Marie-Hélène Jeuffroy Françoise Montfort Philippe Lucas 《Environmental Modeling and Assessment》2011,16(1):91-105
This paper addresses the question of summer cover-crop adoption by farmers in presence of a risk of yield loss due to take-all disease and climate variability. To analyze the public incentives needed to encourage farmers to adopt summer cover crops as a means of reducing N leaching, we combine outputs from an economic, an epidemiological and an agronomic model. The economic model is a simple model of choice under risk. The farmer is assumed to choose among a range of summer fallow managements and input uses on the basis of the expected utility criterion (HARA assumption) in presence of both climate and take-all risks. The epidemiological model proposed by Ennaïfar et al. (Eur J Plant Pathol 118:127–143, 2007) is used to determine the impact of take all on yields and N uptake. The crop-soil model (STICS) is used to compute yield developments and N leaching under various management options and climatic conditions. The input parameters are chosen to match the conditions prevailing in Grignon, located in the main wheat-growing area in France. Eight management systems are examined: four summer fallow managements: ‘wheat volunteers’ (WV), ‘bare soil’ (BS), ‘early mustard’, ‘late mustard’, and two input intensities. We show that the optimal systems are BS (WV) when the take-all risk is (not) taken into account by agents. We then compute the minimum payment to each system such that it emerges in the optimum. We thus derive the required amounts of transfer needed to trigger catch-crop adoption. The results of the Monte Carlo sensitivity analysis show that the ranking of management systems is robust over a wide range of input parameters. 相似文献
50.
Hungshu Wang PhD. Judith L. Bellinger Kathleen Brierley Laura E. Dawson Claire L. Goldsmith Alasdair G. W. Hunter 《黑龙江环境通报》1994,14(9):868-872
Single copies of tiny chromosome fragments, appearing either as single or as double minutes, were observed in a high frequency in amniotic fluid cultures of five mothers who underwent prenatal testing because of advanced age. In four cases, the minutes had arisen de novo. The minutes were later confirmed in fetal skin following termination of pregnancy in one case; in another, in cord blood following the birth of a normal boy; and in the third, in peripheral blood of a normal 3-year-old girl. In the fourth case, the minutes were not confirmed in cord blood following the birth of a normal boy. A follow-up chromosome study of the baby boy in the fifth case was not possible but the minutes were maternally transmitted. 相似文献