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561.
为破解文化和旅游融合发展过程中的困难和挑战,借鉴共生理论、社会互动理论和互惠规范理论,构建了文化和旅游"共生—共建—共享"的关系网络,并进一步从政府、企业和旅游者角度提出文旅融合发展路径,最终构建了文化和旅游在理念、职能、产业、市场、服务和交流方面的六大融合矩阵。  相似文献   
562.
目的 研究铝合金大气腐蚀受自然环境因素的影响性,探索环境因素对铝合金腐蚀的影响规律。方法 采用多层感知器神经网络分析环境因素对7种铝合金平均腐蚀速率的影响。结果 确定了影响铝合金腐蚀损伤的重要因素为SO2沉积率、Cl沉积率、NOx沉积率;辅要因素为年降雨量、年雾露时数、相对湿度、年日照时数、温度、铝合金成分;次要因素为年累积降水时数、雨水pH值。结论 基于多层感知器神经网络分析有效展现了环境因素对平均腐蚀速率的影响性。  相似文献   
563.
Polycentric networks of formal organizations and informal stakeholder groups, as opposed to centralized institutional hierarchies, can be critically important for strengthening the capacity of governance systems to adapt to unexpected social and biophysical change. Adaptive governance is one type of environmental governance characterized by the emergence of networks that stimulate adaptive capacity through increases in social-learning, communication, trust, public participation and adaptive management. However, detecting and analyzing adaptive governance networks remains elusive, especially given contexts of highly contested resource governance such as large-scale negotiations over water use. Research methods such as social network analysis (SNA) are often infeasible as they necessitate collecting in-depth and politically sensitive personal data from a near-complete set of actors or organizations in a network. Here we present a method for resolving this problem by describing the results of an institutional SNA aimed at characterizing the changing governance network in the Klamath River Basin, USA during a period of contested negotiations over water. Through this research, we forward a method of institutional SNA useful when an individual or egocentric approach to SNA is problematic for political, logistical or financial reasons. We focus our analysis on publically available data signaling changes in formal relationships (statutory, regulatory, contractual) between organizations and stakeholder groups. We find that employing this type of SNA is useful for describing potential and actual transitions in governance that yield increases in adaptive capacity to respond to social and biophysical surprises such as increasing water scarcity and changes in water distribution.  相似文献   
564.
Herbarium specimens are increasingly recognized as an important resource for conservation science and virtual herbaria are making specimens freely available to a wider range of users than ever before. Few virtual herbaria are designed with conservation use as a primary driver. Exceptionally, Brazil's Reflora Virtual Herbarium (RVH) was created to increase knowledge and conservation of the Brazilian flora. The RVH is closely integrated with the Flora of Brazil 2020 platform on which Brazil's new national Flora is under construction. Both resources are accessible via the Reflora home page and thousands of users move seamlessly between these Reflora resources. To understand how the Reflora resources are currently used and their impact on conservation science, we conducted a literature review and an online survey. We searched for publications of studies in which Reflora resources were used and publications resulting from Brazilian researchers who were part of Reflora's research and mobility program. The survey contained multiple choice questions and questions that required a written response. We targeted Reflora webpage visitors with the survey to capture a wider range of Reflora users than the literature review. Reflora resources were used for a variety of conservation-relevant purposes. Half the 806 scientific publications in which Reflora was cited and 81% of the 1069 survey respondents accessing Reflora resources mentioned conservation-relevant research outputs. Most conservation-relevant uses of the Reflora resources in scientific publications were research rather than implementation focused. The survey of Reflora users showed conservation uses and impacts of virtual herbaria were more numerous and diverse than the uses captured in the literature review. Virtual herbaria are vital resources for conservation science, but they must document use and impacts more comprehensively to ensure sustainability.  相似文献   
565.
Ecosystem function and resilience are compromised when habitats become fragmented due to land‐use change. This has led to national and international conservation strategies aimed at restoring habitat extent and improving functional connectivity (i.e., maintaining dispersal processes). However, biodiversity responses to landscape‐scale habitat creation and the relative importance of spatial and temporal scales are poorly understood, and there is disagreement over which conservation strategies should be prioritized. We used 160 years of historic post‐agricultural woodland creation as a natural experiment to evaluate biodiversity responses to habitat creation in a landscape context. Birds were surveyed in 101 secondary, broadleaf woodlands aged 10–160 years with ≥80% canopy cover and in landscapes with 0‐17% broadleaf woodland cover within 3000 m. We used piecewise structural equation modeling to examine the direct and indirect relationships between bird abundance and diversity, ecological continuity, patch characteristics, and landscape structure and quantified the relative conservation value of local and landscape scales for bird communities. Ecological continuity indirectly affected overall bird abundance and species richness through its effects on stand structure, but had a weaker influence (effect size near 0) on the abundance and diversity of species most closely associated with woodland habitats. This was probably because woodlands were rapidly colonized by woodland generalists in ≤10 years (minimum patch age) but were on average too young (median 50 years) to be colonized by woodland specialists. Local patch characteristics were relatively more important than landscape characteristics for bird communities. Based on our results, biodiversity responses to habitat creation depended on local‐ and landscape‐scale factors that interacted across time and space. We suggest that there is a need for further studies that focus on habitat creation in a landscape context and that knowledge gained from studies of habitat fragmentation and loss should be used to inform habitat creation with caution because the outcomes are not necessarily reciprocal.  相似文献   
566.
Many conservation interventions are hypothesized to be beneficial for both the environment and people's well-being, but this has rarely been tested rigorously. We examined the effects of adoption or nonadoption of a conservation intervention on 3 dimensions of people's well-being (material, relational, and subjective) over time. We focused on a fisheries bycatch management initiative intended to reduce environmental externalities associated with resource extraction. We collected panel data from fishers (n = 250) in villages with (adopters and nonadopters) and without (control) the conservation intervention 3 times over 2 years. We found no evidence that adoption reduced any of the 3 dimensions of well-being in the local populations affected by the intervention. There were modest improvements in material (t = –1.58) and subjective livelihood well-being (p = 0.04) for adopters relative to nonadopters over time. The variations in well-being experiences (in terms of magnitude of change) among adopters, nonadopters, and controls across the different domains over time affirmed the dynamic and social nature of well-being.  相似文献   
567.
Purpose. In ergonomics and human factors investigations, pulling force (PF) estimation has usually been achieved using various types of biomechanical models, and independent approximation of PF was done with the help of upper extremity joints. Recently, multiple regression methods have gained importance for task-relevant inputs in predicting PF. Artificial neural networks (ANNs) also play a vital role in fitting the data; however, their use in work-related biomechanics and ergonomics is inadequate. Therefore, the current research aimed to accomplish comparative investigation of ANN and regression models by assessing their capacity to predict PF values. Methods. Multipositional PF data were acquired from 200 subjects at three different handle heights and body locations. ANN and regression models were formed using a random sample of three subsets (75% training, 15% selection, 10% validation) for proving the outcomes. Results. The comparison of ANN and regression models shows that the predictions of ANN models had a profoundly explained variance and lower root mean square difference values for the PF data at three handle heights. Conclusions. These outcomes advise that ANNs offer a precise and robust substitute for regression methods, and should be considered a useful method in biomechanics and ergonomics task assessments.  相似文献   
568.
The aim of this study was to investigate the feasibility of using visible near-infrared (VisNIR) diffuse reflectance spectroscopy (DRS) as an easy, inexpensive, and rapid method to predict compost enzymatic activity, which traditionally measured by fluorescein diacetate hydrolysis (FDA-HR) assay. Compost samples representative of five different compost facilities were scanned by DRS, and the raw reflectance spectra were preprocessed using seven spectral transformations for predicting compost FDA-HR with six multivariate algorithms. Although principal component analysis for all spectral pretreatments satisfactorily identified the clusters by compost types, it could not separate different FDA contents. Furthermore, the artificial neural network multilayer perceptron (residual prediction deviation = 3.2, validation r2 = 0.91 and RMSE = 13.38 μg g?1 h?1) outperformed other multivariate models to capture the highly non-linear relationships between compost enzymatic activity and VisNIR reflectance spectra after Savitzky–Golay first derivative pretreatment. This work demonstrates the efficiency of VisNIR DRS for predicting compost enzymatic as well as microbial activity.  相似文献   
569.
In this paper we examine and compare communication processes aimed at building social networks and increasing citizen engagement in two communities participating in a municipal sustainability planning (MSP) pilot programme in Alberta, Canada, initiated by the Alberta Urban Municipalities Association (AUMA). Data were gathered through qualitative semi-structured interviews and documentary review. In soliciting citizen engagement, each community utilised a variety of communication methods, based on available resources and on-going evaluation of community responses. In both cases, citizens developed a shared vision of a preferred future for their community, aided by a reconfiguration of their internal and external social networks. In addition to drawing upon and strengthening bonding relationships within the community, bridging relationships with external actors and agencies promoted knowledge mobilisation that aided in planning and transitioning towards sustainability. Both communities faced challenges as well, which the authors discuss in relation to the sustainability of MSP planning.  相似文献   
570.
斜坡稳定性评估神经网络专家系统N^2ES^3E   总被引:3,自引:0,他引:3  
夏元友  朱瑞赓 《灾害学》1998,13(4):7-11
在于工程实列,采用神经网络理论,建立了斜坡稳定性评估分支结构专家系统,并针对斜坡评价的不同阶段,分别建立了以地质信息为3指标和斜坡的几何与力学参数为评价指标的两种评估系统。文中阐述了该系统的开发设想,介绍了系统的主要组成部分,同时给出了应用实例,应用结果表明该系统是有效的。  相似文献   
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