首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2178篇
  免费   140篇
  国内免费   130篇
安全科学   287篇
废物处理   50篇
环保管理   499篇
综合类   839篇
基础理论   268篇
环境理论   1篇
污染及防治   103篇
评价与监测   65篇
社会与环境   213篇
灾害及防治   123篇
  2024年   7篇
  2023年   19篇
  2022年   53篇
  2021年   70篇
  2020年   89篇
  2019年   51篇
  2018年   37篇
  2017年   69篇
  2016年   73篇
  2015年   74篇
  2014年   90篇
  2013年   149篇
  2012年   158篇
  2011年   159篇
  2010年   111篇
  2009年   100篇
  2008年   81篇
  2007年   139篇
  2006年   127篇
  2005年   92篇
  2004年   114篇
  2003年   82篇
  2002年   73篇
  2001年   69篇
  2000年   76篇
  1999年   50篇
  1998年   37篇
  1997年   29篇
  1996年   30篇
  1995年   15篇
  1994年   22篇
  1993年   31篇
  1992年   17篇
  1991年   7篇
  1990年   8篇
  1989年   5篇
  1988年   5篇
  1987年   6篇
  1986年   4篇
  1983年   4篇
  1982年   1篇
  1981年   1篇
  1979年   1篇
  1977年   1篇
  1975年   1篇
  1974年   3篇
  1973年   2篇
  1971年   3篇
  1970年   1篇
  1969年   1篇
排序方式: 共有2448条查询结果,搜索用时 15 毫秒
71.
How do youth learn through participation in efforts to study and change the school food system? Through our participatory youth action research (YPAR) project, we move beyond the “youth as consumer” frame to a food justice youth development (FJYD) approach. We track how a group of youth learned about food and the public policy process through their efforts to transform their own school food systems by conducting a participatory evaluation of farm-to-school efforts in collaboration with university and community partners. We used the Photovoice research method, placing cameras in the hands of young people so that they themselves could document and discuss their concerns and perspectives. The research was designed to gain insight about youths’ knowledge of food, health, and community food systems. Drawing upon the youth group’s insights, we build a framework for building critical consciousness through FJYD.  相似文献   
72.
In a world of shrinking habitats and increasing competition for natural resources, potentially dangerous predators bring the challenges of coexisting with wildlife sharply into focus. Through interdisciplinary collaboration among authors trained in the humanities, social sciences, and natural sciences, we reviewed current approaches to mitigating adverse human–predator encounters and devised a vision for future approaches to understanding and mitigating such encounters. Limitations to current approaches to mitigation include too much focus on negative impacts; oversimplified equating of levels of damage with levels of conflict; and unsuccessful technical fixes resulting from failure to engage locals, address hidden costs, or understand cultural (nonscientific) explanations of the causality of attacks. An emerging interdisciplinary literature suggests that to better frame and successfully mitigate negative human–predator relations conservation professionals need to consider dispensing with conflict as the dominant framework for thinking about human–predator encounters; work out what conflicts are really about (they may be human–human conflicts); unravel the historical contexts of particular conflicts; and explore different cultural ways of thinking about animals. The idea of cosmopolitan natures may help conservation professionals think more clearly about human–predator relations in both local and global context. These new perspectives for future research practice include a recommendation for focused interdisciplinary research and the use of new approaches, including human‐animal geography, multispecies ethnography, and approaches from the environmental humanities notably environmental history. Managers should think carefully about how they engage with local cultural beliefs about wildlife, work with all parties to agree on what constitutes good evidence, develop processes and methods to mitigate conflicts, and decide how to monitor and evaluate these. Demand for immediate solutions that benefit both conservation and development favors dispute resolution and technical fixes, which obscures important underlying drivers of conflicts. If these drivers are not considered, well‐intentioned efforts focused on human–wildlife conflicts will fail.  相似文献   
73.
Use of the arts in international aid is common in an ad hoc form, but it has not been systematically theorised or evaluated. The arts have the potential to be a culturally contextualised and sustainable intervention for adults and children in the aftermath of war or disaster. On the micro level, the arts are a method to enable the retrieval and reprocessing of traumatic memories that are often encoded in images rather than in words. On a macro level, they can help to reconstruct a group narrative of a disaster as well as mobilise people back into control of their lives. This paper researches a long‐term project using arts in Sri Lanka following the civil war and tsunami. A central finding is the need to understand arts within their cultural context, and their usefulness in strengthening the voices and problem‐solving capacities of the victims of the disaster.  相似文献   
74.
Natural scientists are increasingly interested in social research because they recognize that conservation problems are commonly social problems. Interpreting social research, however, requires at least a basic understanding of the philosophical principles and theoretical assumptions of the discipline, which are embedded in the design of social research. Natural scientists who engage in social science but are unfamiliar with these principles and assumptions can misinterpret their results. We developed a guide to assist natural scientists in understanding the philosophical basis of social science to support the meaningful interpretation of social research outcomes. The 3 fundamental elements of research are ontology, what exists in the human world that researchers can acquire knowledge about; epistemology, how knowledge is created; and philosophical perspective, the philosophical orientation of the researcher that guides her or his action. Many elements of the guide also apply to the natural sciences. Natural scientists can use the guide to assist them in interpreting social science research to determine how the ontological position of the researcher can influence the nature of the research; how the epistemological position can be used to support the legitimacy of different types of knowledge; and how philosophical perspective can shape the researcher's choice of methods and affect interpretation, communication, and application of results. The use of this guide can also support and promote the effective integration of the natural and social sciences to generate more insightful and relevant conservation research outcomes. Una Guía para Entender la Investigación de Ciencias Sociales para las Ciencias Naturales Katie Moon  相似文献   
75.
Understanding human perspectives is critical in a range of conservation contexts, for example, in overcoming conflicts or developing projects that are acceptable to relevant stakeholders. The Q methodology is a unique semiquantitative technique used to explore human perspectives. It has been applied for decades in other disciplines and recently gained traction in conservation. This paper helps researchers assess when Q is useful for a given conservation question and what its use involves. To do so, we explained the steps necessary to conduct a Q study, from the research design to the interpretation of results. We provided recommendations to minimize biases in conducting a Q study, which can affect mostly when designing the study and collecting the data. We conducted a structured literature review of 52 studies to examine in what empirical conservation contexts Q has been used. Most studies were subnational or national cases, but some also address multinational or global questions. We found that Q has been applied to 4 broad types of conservation goals: addressing conflict, devising management alternatives, understanding policy acceptability, and critically reflecting on the values that implicitly influence research and practice. Through these applications, researchers found hidden views, understood opinions in depth and discovered points of consensus that facilitated unlocking difficult disagreements. The Q methodology has a clear procedure but is also flexible, allowing researchers explore long‐term views, or views about items other than statements, such as landscape images. We also found some inconsistencies in applying and, mainly, in reporting Q studies, whereby it was not possible to fully understand how the research was conducted or why some atypical research decisions had been taken in some studies. Accordingly, we suggest a reporting checklist.  相似文献   
76.
Many argue that monitoring conducted exclusively by scientists is insufficient to address ongoing environmental challenges. One solution entails the use of mobile digital devices in participatory monitoring (PM) programs. But how digital data entry affects programs with varying levels of stakeholder participation, from nonscientists collecting field data to nonscientists administering every step of a monitoring program, remains unclear. We reviewed the successes, in terms of management interventions and sustainability, of 107 monitoring programs described in the literature (hereafter programs) and compared these with case studies from our PM experiences in Australia, Canada, Ethiopia, Ghana, Greenland, and Vietnam (hereafter cases). Our literature review showed that participatory programs were less likely to use digital devices, and 2 of our 3 more participatory cases were also slow to adopt digital data entry. Programs that were participatory and used digital devices were more likely to report management actions, which was consistent with cases in Ethiopia, Greenland, and Australia. Programs engaging volunteers were more frequently reported as ongoing, but those involving digital data entry were less often sustained when data collectors were volunteers. For the Vietnamese and Canadian cases, sustainability was undermined by a mismatch in stakeholder objectives. In the Ghanaian case, complex field protocols diminished monitoring sustainability. Innovative technologies attract interest, but the foundation of effective participatory adaptive monitoring depends more on collaboratively defined questions, objectives, conceptual models, and monitoring approaches. When this foundation is built through effective partnerships, digital data entry can enable the collection of more data of higher quality. Without this foundation, or when implemented ineffectively or unnecessarily, digital data entry can be an additional expense that distracts from core monitoring objectives and undermines project sustainability. The appropriate role of digital data entry in PM likely depends more on the context in which it is used and less on the technology itself.  相似文献   
77.
在实地调研湖北赤壁的基础上,探讨AHP-SWOT法在城市圈建设过程中的耕地保护策略分析中的应用.结果表明,耕地异地占补平衡是主要优势,耕地数量持续减少是主要劣势,新一轮土地利用总体规划是主要机遇,城市圈建设占用耕地是主要威胁,建议赤壁市在城市圈建设过程中应发挥耕地异地占补平衡优势,回避城市圈建设占用耕地的威胁.  相似文献   
78.
王永琴  周叶  张荣 《环境工程》2017,35(1):155-159
从研究方法的角度出发,对近年来国内外碳排放影响因子及碳足迹的相关研究进行文献综述。根据碳排放影响因子的研究方法—情景分析法、因素分解法中的指数分解法以及其他计量模型,介绍了国内外关于碳排放影响因子的研究现状,最后对方法进行归类和对比。根据碳足迹研究方法—投入产出法、生命周期评价法、IPCC法以及其他模型,分析了国内外关于碳足迹的研究进展。最后通过总结,对碳排放和碳足迹的未来研究方向进行了展望。  相似文献   
79.
我国土壤修复行业面临的问题及商业模式分析   总被引:1,自引:0,他引:1       下载免费PDF全文
基于我国土壤污染的严峻形势,分析了我国土壤修复行业面临的主要问题。针对我国土壤修复资金需求量大,资金来源困难、责任界定情况复杂等现状,探讨了"谁污染,谁治理"、"谁使用,谁治理"、"政府出资"、RT、ROT、ROO、TRT等几种适合我国国情的土壤修复商业模式。同时,结合我国土壤修复行业正处于成长期初级阶段的现实情况,展望了我国土壤修复行业的发展,并给出了一些有益建议。  相似文献   
80.
为考察自养脱氮污泥亚硝化活性快速恢复的策略,在3个反应器内分别采用不同的方法对经过长期冷冻保存后的污泥进行了恢复活性的研究.其中R1为MBR(膜生物反应器),采用低ρ(DO)(0.30 mg/L)连续流恢复策略;R2为SBR(序批式反应器),采用低ρ(DO)(0.30 mg/L)间歇流恢复策略;R3为SBR,采用低ρ(NH4+-N)预培养-高曝气-低ρ(DO)运行三阶段的恢复策略.结果表明,R1的恢复时间为46 d,NH4+-N氧化速率达到4.99 mg/(h·g)(以N计),最终ρ(MLSS)达到5.43 g/L;R2的恢复时间为39 d,NH4+-N氧化速率达到4.61 mg/(h·g),最终ρ(MLSS)达到4.47 g/L;R3的恢复时间为48 d,NH4+-N氧化速率达到5.64 mg/(h·g),最终ρ(MLSS)达到5.16 g/L. 3个反应器均能长期抑制亚硝酸盐氧化细菌的活性,使亚硝化稳定运行. 3个反应器中,R3恢复所需时间最长,但污泥活性最好; R1中的污泥活性较低,但是膜组件有效截留了污泥,达到了最高的ρ(MLSS).研究显示,通过厌氧预培养后转为膜生物反应器连续流运行的策略,可有助于污泥的极大保留及污泥活性的最大恢复.   相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号