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31.
The prevalence of diversity training has not been matched by empirical research on its effectiveness. Among the most notable gaps are an absence of attention to its impact on discrimination and limited consideration of organizational‐level factors. Results from employee surveys across 395 healthcare organizations reveal an effect of the extent of diversity training in organizations on ethnic minorities' experiences of discrimination. In addition, the results demonstrate that the consequences of ethnic discrimination for individuals' job attitudes are influenced by organizational‐level phenomenon. These findings highlight the importance of attending to ethnic discrimination as an outcome of diversity training with implications for employee attitudes. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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This special issue of the Journal of Organizational Behavior was developed to further extend attribution theory and its application to the field of organizational behavior. In this introduction, we provide a brief overview of the motivation for this special issue, a concise summary of the papers included in it, a discussion about progress toward the field's goals, and suggestions for how future research can move the field forward. In doing so, we describe how applying attribution theory to studies that utilize a broad range of study designs, research contexts, and focal topics results in insights that enhance our understanding of how attributional processes predict and explain individuals' emotions and behaviors. We also provide suggestions for how to further develop attribution theory so we can more clearly describe the generalizability of relationships across a wide variety of organizational contexts. 相似文献
35.
Biodiversity across a Rural Land-Use Gradient 总被引:6,自引:0,他引:6
Jeremy D. Maestas § Richard L. Knight † Wendell C. Gilgert‡ 《Conservation biology》2003,17(5):1425-1434
36.
Summary In an attempt to examine three main hypotheses on the evolution of leks, data on female home ranges, distance between leks and male site fidelity in the great snipe (Gallinago media) were obtained. In a 30 × 40 km area in central Sweden, the locations of 12 leks were identified. Six were within the study area (7 × 11 km) in which probably all leks were known. In the study area, nearest neighbor distances between leks were longer than the predicted drawing area (diameter of female home ranges plus the detection range of leks). Furthermore, in only 1 of 13 radio-tracked females did the estimated home range enclose many leks. These data do not fit the prediction from the hotspot hypothesis on the dispersion of leks, namely, that the distance between leks should be less than the drawing area and hence an average female home range should enclose more than one lek. The observed distance between leks was about the same as predicted by the female preference hypothesis. This hypothesis also predicts females visit mainly one lek; however, we found they sometimes visit two and nest close to a third. We propose that males may first settle according to hotspot rules, but females will resettle according to preferences for certain males and/or larger leks. In this way some hotspot leks are abandoned, and the distance between leks is increased as males become more tightly clumped. However, when all males and females have settled, the leks still existing would be on hotspots. In the female preference hypothesis, males are assumed to aggregate on leks because females prefer clustered males as they can be more easily compared than if they are dispersed. Alternatively, in the attractiveness hypothesis, it is suggested that females prefer certain males, and hence unattractive males surround the attractive are forced to join leks in order to come close to females. Our data on male site fidelity support the attractiveness hypothesis because successful and dominant males return to the same lek and territory, both within and between years, whereas unsuccessful males move to other leks. Attractiveness of certain males may explain why according to hotspot rules in this species males are more clumped than expected.
Offprint requests to: J. Höglund 相似文献
37.
In Lepidoptera polyandry is common and females may increase their lifetime reproductive output through repeated matings if they acquire essential resources from male ejaculates. However, the paternity of males mating with previously-mated females is far from assured unless sperm precedence is absolute. In this study on the polyandrous armyworm, Pseudaletia unipuncta, we used two strains of male (the black-eyed wild type and a red-eyed homozygous, recessive mutant), mated with red-eyed females, to determine (i) whether male investment has any impact on female reproductive output, and (ii) if females do benefit from multiple matings, to what extent males fertilize the eggs to which they contributed. Multiple mating resulted in a significant increase in both the fecundity and longevity of females. However, the degree of sperm precedence (those eggs fertilized by the second male) varied from 0–100%, but was not affected by either male size or age, or by the duration of copulation. In cases where sperm precedence was <50% (x = 12%) females produced significantly more eggs (1384 versus 940) prior to the second mating than females where sperm precedence was >50% (x = 89%), indicating that the quality of the first mating influenced the fertilization success of the female's second mate. 相似文献
38.
Aneil?F.?AgrawalEmail author Jeremy?M.?Brown Edmund?D.?BrodieIII 《Behavioral ecology and sociobiology》2004,57(2):139-148
Maternal-offspring interactions are important in a variety of animals. Understanding the evolution of these interactions requires that we also study the broader social context in which they occur. To date, behavioral studies on burrower bugs, Sehirus cinctus, have focused exclusively on interactions between mothers and offspring. Here we ask whether these interactions occur in a social context that extends beyond the family unit of a mother and her own genetic offspring. Such social structure can arise from behaviors that occur before eggs are laid, or from actions of individuals that occur post-hatching. We present field data showing that lay sites of mothers are spatially aggregated on a scale that would lead to behavioral interactions among families. Microsatellite markers suggest neighboring mothers are unrelated. Laboratory experiments do not support the hypothesis that spatial aggregation results from a direct attraction of females to one another. Other laboratory studies reported here indicate that, after hatching, unrelated clutches sometimes join together to form multifamily groups. Experiments reveal that mothers are not necessary for these joining events to occur. In sum, these data suggest that both mothers and offspring play active, but different, roles in generating the social environment in which offspring rearing occurs.Communicated by N. Wedell 相似文献
39.
The context of famine in Turkana has changed in recent years as the role played by livestock raiding in contributing to famine has increased. External responses to famine in Turkana have largely been drought driven, for example, food assistance and livestock restocking programmes, which have failed to meet the real needs of herders. The role of armed conflict in the form of raiding has been overlooked as a common feature of societies facing famine and food insecurity.The traditional livelihood-enhancing functions of livestock raiding are contrasted with the more predatory forms common today. The direct impact of raiding on livelihood security can be devastating, while the threat of raids and measures taken to cope with this uncertainty undermine herders' livelihood strategies. Self-imposed restrictions on mobility negatively affect the vegetation of both grazed and ungrazed pastures and restrict the available survival strategies. Predatory raiding leads to a collapse in the moral economy. Some implications of this for relief and development policy are considered, including approaches to conflict resolution. 相似文献
40.
Marek K. Jarecki Timothy B. Parkin Alvarus S.K. Chan Thomas C. Kaspar Thomas B. Moorman Jeremy W. Singer Brian J. Kerr Jerry L. Hatfield Raymond Jones 《Agriculture, ecosystems & environment》2009,134(1-2):29-35
Agriculture contributes 40–60% of the total annual N2O emissions to the atmosphere. Development of management practices to reduce these emissions would have a significant impact on greenhouse gas levels. Non-leguminous cover crops are efficient scavengers of residual soil NO3, thereby reducing leaching losses. However, the effect of a grass cover crop on N2O emissions from soil receiving liquid swine manure has not been evaluated. This study investigated: (i) the temporal patterns of N2O emissions following addition of swine manure slurry in a laboratory setting under fluctuating soil moisture regimes; (ii) assessed the potential of a rye (Secale cereale L.) cover crop to decrease N2O emissions under these conditions; and (iii) quantified field N2O emissions in response to either spring applied urea ammonium nitrate (UAN) or different rates of fall-applied liquid swine manure, in the presence or absence of a rye/oat winter cover crop. Laboratory experiments investigating cover crop effects N2O emissions were performed in a controlled environment chamber programmed for a 14 h light period, 18 °C day temperature, and 15 °C night temperature. Treatments with or without a living rye cover crop were treated with either: (i) no manure; (ii) a phosphorus-based manure application rate (low manure): or (iii) a nitrogen-based manure application rate (high manure). We observed a significant reduction in N2O emissions in the presence of the rye cover crop. Field experiments were performed on a fine-loamy soil in Central Iowa from October 12, 2005 to October 2, 2006. We observed no significant effect of the cover crop on cumulative N2O emissions in the field. The primary factor influencing N2O emission was N application rate, regardless of form or timing. The response of N2O emission to N additions was non-linear, with progressively more N2O emitted with increasing N application. These results indicate that while cover crops have the potential to reduce N2O emissions, N application rate may be the overriding factor. 相似文献