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231.
全球环境变化对农作物影响的研究进展   总被引:14,自引:2,他引:14  
从CO2浓度升高、CO2浓度与温度升高以及CO2浓度与水分变化的协同作用、CO2浓度升高与环境盐胁迫的协同作用和作物产量预测模拟及其适应对策4个方面总结了近年来国内外关于农业生产对全球环境变化的响应与适应及其变化趋势的研究进展,指出目前人类关于农业生产对未来全球环境变化响应机理的理解与预测很有限,提出中国未来需要拟加强的研究领域.参38  相似文献   
232.
Agricultural adaptation to climate change in China   总被引:4,自引:0,他引:4  
IntroductionAdaptationreferstoeffortstoreducesystem’svulnerabilitiestoclimate.Amongthemostfrequentlycitedhumansystemslikelytobeaffectedbyclimaticchangeisagriculture.Itisespeciallysensitivetotheconsequencesofglobalwarmingasitreliesheavilyontheweatheran…  相似文献   
233.
Adaptation in response to anthropogenic climate change seeks to maintain viability by maximising benefits and minimising losses. It is necessary because some climatic change is now inevitable, despite the international focus on mitigation measures. Indeed, the measures agreed at Kyoto would by themselves result in only a small reduction in the climate changes to be expected over the next century.Discussion of the expected changes and possible impacts leads to the following conclusions regarding climate change scenarios in relation to impacts and adaptation: Climate change in the foreseeable future will not be some new stable "equilibrium" climate, but rather an ongoing "transient" process; Climate change predictions relevant to impacts on most sectors and ecosystems are still highly uncertain; There is a need for a greater focus on developing countries and tropical regions, and on relevant key variables, including the magnitude and frequency of extreme events; The focus should shift from single predictions, or extreme ranges of uncertainty, to risk assessment; Thresholds critical to impacted sectors and ecosystems should be identified, and expressed as functions of climatic variables; Planned adaptations will be necessary to cope with multiple stresses, including those due to non-climatic changes; A major task of adaptation science is to identify the limits of adaptation, i.e., to identify "dangerous levels of greenhouse gases" beyond which adaptation becomes impractical or prohibitively expensive.  相似文献   
234.
Climate change adaptation strategies that aim to minimize harm and maximize benefits related to climate change impacts have mushroomed at all levels of government in recent years. While many studies have explored barriers that stand in the way of their implementation, the factors determining their potential to mainstream adaptation into various sectors are less clear. In the present paper, we aim to address this gap for two international, six national, and six local adaptation strategies. Based on document analyses and 35 semi‐structured interviews, the 14 case studies also explore in how far the factors facilitating climate change adaptation are similar across levels of government or level‐specific. Although located at three different levels of government, we find that the 14 adaptation strategies analyzed here represent “one‐size‐fits‐all governance arrangements” that are characterized by voluntariness and a lack institutionalization. Since adaptation strategies are relatively weak coordination hubs that are unable to force adaptation onto sectoral policy agendas, they rely mainly on sectoral self‐interest in adapting to climate change, largely determined by problem pressure. We conclude that one‐size‐fits‐all governance arrangements are rarely adequate responses to complex challenges, such as climate change. Although climate change adaptation depends more on framework conditions such as problem pressure than on administrative or governance features, the findings presented here can help to understand under what circumstances adaptation is likely to make progress.  相似文献   
235.
为了对飞行员的不安全行为进行科学有效的管理,挖掘组织因素带来的深层影响,防止因飞行员不安全行为造成的不安全事件发生,运用系统动力学方法,构建组织因素对飞行员不安全行为的干预策略模型。以S航空公司为研究对象,通过调节组织因素中的飞行技术训练力度和奖惩力度等变量,制定不同的干预策略,运用VENSIM软件模拟不同干预策略的干预结果。研究结果表明:飞行员不安全行为的最佳干预策略组合为安全记录考核奖励程度、副驾驶转正/机长升职力度、监管力度、罚款力度、飞行技术训练强度的组合,到2020年实现不安全行为数量平均降低26%,在2020年改变干预策略数值,到2030年实现不安全行为数量平均降低54%。  相似文献   
236.
In this study, we investigate, through two study samples, whether relationships between social leader–member exchange (SLMX) and economic leader–member exchange (ELMX) relationships and outcomes differ depending on the followers' level of other orientation or the extent to which they are concerned for the welfare of others. We propose that followers with higher other orientation would respond less negatively to higher levels of ELMX and more positively to higher levels of SLMX because they are less likely to engage in behaviors based on rational and self‐interested calculations. In Study 1 (N = 200), we found that higher other orientation mitigated ELMX's negative relations with affective commitment and turnover intention. In Study 2 (N = 4,518), we both replicated the findings from Study 1 and also found that higher other orientation mitigated ELMX's negative relations with work effort. We also uncovered a weaker positive relationship between SLMX and organizational citizenship behavior for followers with higher other orientation.  相似文献   
237.
Despite significant interest in the attributions employees make about their organization's human resource (HR) practices, there is little understanding of the antecedents of HR attributions. Drawing on attribution theory, we suggest that HR attributions are influenced by information (perceptions of distributive and procedural fairness), beliefs (organizational cynicism), and motivation (perceived relevance). We test a model through a two‐wave survey of 347 academic faculty in the United Kingdom, examining their attributions of the purpose of their institution's workload management framework. After two preliminary studies (an interview study and a cross‐sectional survey) to establish contextually relevant attributions, we find that fairness and cynicism are important for the formation of internal attributions of commitment but less so for cost‐saving or exploitation attributions. Fairness and cynicism also interact such that distributive fairness buffers the negative attributional effect of cynicism, and individuals are more likely to attribute fair procedures to external forces if they are cynical about their organization. This study furthers the application of attribution theory to the organizational domain while making significant contributions to our understanding of the HR‐performance process.  相似文献   
238.
Drawing on fairness heuristics theory (Lind, 2001) and cue consistency theory (Maheswaran & Chaiken, 1991; Slovic, 1966), we test a moderated mediation model that examines whether the institutionalization of organizational socialization tactics enhances or constrains the beneficial effects of supervisory and coworker‐referenced justice and support on newcomer role clarity and social integration. The findings of a three‐wave study of 219 French newcomers show that although institutionalized tactics strengthen the positive indirect effects of supervisory interpersonal and informational justice on role clarity, via perceived supervisor support, it also acts as a substitute that weakens the positive indirect effect of coworker‐referenced interpersonal justice on social integration, via perceived coworker support. Implications of the findings for socialization research and practice are discussed.  相似文献   
239.
Aim. The objective of the present study was to test the psychometric properties, reliability and validity of three job stressor measures, namely, the Interpersonal Conflict at Work Scale, the Organizational Constraints Scale and the Quantitative Workload Inventory. Method. The study was conducted on two samples (N?=?382 and 3368) representing a wide range of occupations. The estimation of internal consistency with Cronbach's α and the test–retest method as well as both exploratory and confirmatory factor analyses were the main statistical methods. Results. The internal consistency of the scales proved satisfactory, ranging from 0.80 to 0.90 for Cronbach's α test and from 0.72 to 0.86 for the test–retest method. The one-dimensional structure of the three measurements was confirmed. The three scales have acceptable fit to the data. The one-factor structures and other psychometric properties of the Polish version of the scales seem to be similar to those found in the US version of the scales. It was also proved that the three job stressors are positively related to all the job strain measures. Conclusions. The Polish versions of the three analysed scales can be used to measure the job stressors in Polish conditions.  相似文献   
240.
The impacts of natural disasters on communities living in hazard prone areas are wide ranging and complex. In Mwanza, steep slopes, rocky hills and river valleys are inhabited by society's poorest people. These areas are prone to natural disasters. Residents have accumulated coping mechanisms for disaster risks and impact reduction. We combine spatial data, household surveys and data from focus groups to identify and rank areas based on their exposure to major disasters. We also examine household and communal mitigation efforts in relation to these disasters. Most areas of the city are exposed to at least one of the natural disasters studied. Pre- and post-disaster risk reduction measures are influenced by the site of homesteads and the socioeconomic situation of households. Current resilience measures are skewed towards the development of physical infrastructure. The challenge of reducing disaster risks in Mwanza involves recognizing the role of non-infrastructure based factors that promote urban resilience to natural disasters.  相似文献   
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