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781.
低碳农业对农产品安全的影响研究   总被引:1,自引:0,他引:1  
针对我国现代农业、农产品生产及安全的现状,深入分析高碳农业对农产品安全的危害,阐述低碳农业与农产品安全的关系,探讨低碳农业对农产品安全的保障机理,探索发展低碳农业、保障农产品安全实现的途径。通过对英国、美国以及国内有机农业实践的研究,指出保障农产品安全的关键因素是将农业的生态系统和经济系统结合起来,减少以化石燃料为基础的要素投入,提高农业系统生产力。该研究成果对加快转变农业发展模式,实现农业可持续发展,降低农产品的安全隐患具有一定的理论指导和实践参考价值。  相似文献   
782.
本文结合扬州市农业生产的实际,重点从化肥投入量的控减、农作物秸秆和畜禽粪便的资源化再利用等三个方面,分析扬州市农业节能减排的潜力。结果表明,扬州市农业节能减排的潜力巨大,只要完善相应的节能减排措施,通过农业生产节能和农业生产废弃物的能源化利用,每年可产生330万t煤炭的节能效益。据此,提出了推进扬州市农业节能减排的对策。  相似文献   
783.
论观光农业及其可持续发展的基本策略   总被引:1,自引:0,他引:1  
观光农业是农业生产和经营形式的创新,是农业和旅游业交叉产生的新产业.本文分析了观光农业的创新意义、开发模式,提出了实现其可持续发展的基本思路.  相似文献   
784.
论郊区农业生态环境建设的几个问题   总被引:1,自引:0,他引:1  
在对郊区环境组成、结构、生态环境特征等区域研究的基础上 ,以边缘效应的理论为出发点 ,深入分析了城乡交错带的几个生态环境建设问题。认为郊区生态建设应以 (1)城市废弃物的再生地 ,(2 )生态旅游与农业文化的消费地 ,(3)现代持续农业的先导区等为目标。最后分析了城乡交错面 (边缘界面 )对城乡复合生态系统中环境应力的聚合放大效应 ,指出效区农业生态环境的调控是防止城乡矛盾激化的根本措施  相似文献   
785.
1 Meteorological and biological disasters are major constraints to agriculturaldevelopment.1 .1 Meteorological disasters represented by flood and drought and the most serious threat toagricultural production.According to a survey,the average annual droughty farmland for the period 1 95 1~ 1 988wasapproximately 2× 1 0 7hm2 ;the total loss of grain caused by drought disaster only has amountedto1 .5 32 1× 1 0 11kg in the last30 years,accounting for5 0 % of the national total.Meanwhile,China is…  相似文献   
786.
Common property resources are areas of land or water being used by a community or a group of communities. These have special significance to peoples and communities who depend on them for their livelihood. The commons in all arid districts of India include village pastures, community forests, wasteland, common threshing grounds, waste dumps, watershed drainage, village baoris1, talabs2, nadis3 and ponds, and tanks, rivers, rivulets, wetlands, riverbeds, community conserved areas, protected areas, Dhaam4 or Dhooni5, culturable wastelands, barren & un-culturable land, etc. The area under commons often ranged from 9 to 28% of total village area. Appropriation of the commons by the state for building essential infrastructure such as schools, clinics, veterinary hospitals, housing for government functionaries, SEZ and industrial corridors, etc. is a cause of serious concern. Presently the ownership rights over CPRs are not clear and there are many who claim ownership, some at State level but also like local bodies. The 12th plan of the Planning Commission of India recognized and highlighted the need for favourable land tenure arrangements, institutional design and programme architecture in order to achieve effective governance and management of the commons. The revitalization of CPRs is crucial for protecting livelihoods, as well as for biodiversity conservation and for the improvement in arid microclimatic conditions. Dialogue continues on the status of common property resources, the available legal framework and some policy related issues for its conservation through strengthening of local institutions and capacity building for stakeholders.  相似文献   
787.
Graham W. Prescott  William J. Sutherland  Daniel Aguirre  Matthew Baird  Vicky Bowman  Jake Brunner  Grant M. Connette  Martin Cosier  David Dapice  Jose Don T. De Alban  Alex Diment  Julia Fogerite  Jefferson Fox  Win Hlaing  Saw Htun  Jack Hurd  Katherine LaJeunesse Connette  Felicia Lasmana  Cheng Ling Lim  Antony Lynam  Aye Chan Maung  Benjamin McCarron  John F. McCarthy  William J. McShea  Frank Momberg  Myat Su Mon  Than Myint  Robert Oberndorf  Thaung Naing Oo  Jacob Phelps  Madhu Rao  Dietrich Schmidt‐Vogt  Hugh Speechly  Oliver Springate‐Baginski  Robert Steinmetz  Kirk Talbott  Maung Maung Than  Tint Lwin Thaung  Salai Cung Lian Thawng  Kyaw Min Thein  Shwe Thein  Robert Tizard  Tony Whitten  Guy Williams  Trevor Wilson  Kevin Woods  Alan D. Ziegler  Michal Zrust  Edward L. Webb 《Conservation biology》2017,31(6):1257-1270
Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long‐running civil war. With these transitions in mind, we used a horizon‐scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land‐tenure insecurity, large‐scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure‐ and energy‐project planning, and reforming land‐tenure and environmental‐protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.  相似文献   
788.
SUMMARY

Plantain (Musa AAB), a primary food crop in Ghana, is a key component in sustainable agricultural systems in high rainfall zones. Recently, there has been a substantial yield decline and reduction in plantation life. To elucidate the context in which intervention strategies should be developed, a Participatory Rural Appraisal (PRA) was conducted at five villages in the major plantain-producing belt of Ghana. The importance of plantain as a preferred food was confirmed, although farmers tended to sell plantain for cash income, using cheaper, less preferred alternatives for home consumption. Farmers identified decreasing soil fertility, the high cost of labour for weeding, pests and diseases, lack of good quality planting material and marketing-related issues as the major production constraints. Due to declining productivity in less fertile regions, plantain has been replaced with other food crops such as cassava and maize. Farmers overestimated the importance of insect pests but were unaware of the extensive damage that could be caused by nematodes and the foliar disease, black sigatoka. They observed, however, that pest damage is more severe when soil fertility is poor. Clearly, integrated pest management is likely to be most effective when practiced within the context of cropping systems management; sustainable strategies that are being developed for resource-limited plantain farmers in Ghana are discussed.  相似文献   
789.
Habitat loss and degradation are primary threats to amphibians and reptiles, but the relative effects of common land uses on assemblages and the mechanisms that underlie faunal responses are poorly studied. We reviewed the effects of four prevalent types of habitat alteration (urbanization, agriculture, livestock grazing, and silviculture) on amphibian and reptile species richness and abundance by summarizing reported responses in the literature and by estimating effect sizes across studies for species richness in each land‐use type. We then used a multinomial model to classify species as natural habitat specialists, generalists, and disturbed habitat specialists and examined variation in effect sizes for each land‐use type according to habitat specialization categories. There were mixed conclusions from individual studies, some reporting negative, neutral, or positive effects of land use on species richness and total abundance. A large proportion of studies reported species‐specific effects of individual species abundance. However, in our analysis of effect sizes, we found a general trend of negative effects of land use on species richness. We also demonstrate that habitat associations of common species and species turnover can explain variation in the effect of land use on herpetofauna. Our review highlights the pervasive negative effects of common land uses on amphibians and reptiles, the importance of identifying groups vulnerable to land‐use change (e.g., forest‐associated species) in conservation studies, and the potential influence of disturbance‐associated species on whole assemblage analyses.  相似文献   
790.
西北干旱区发展节水农业保障体系研究   总被引:1,自引:0,他引:1  
水资源短缺已成为西北干旱区严重的制约因素之一.实施节水型农业模式,成为促进西北干旱区农业持续发展、生态环境保护乃至整个社会经济发展的必要选择.结合西北干旱区水资源开发利用的现状和节水农业发展中存在的主要问题,构建了西北干旱区节水型农业发展的保障体系:加强宣传培训,提高节水农业意识;制定科学规划,促进农业持续发展;构建完整体系,支持节水农业发展;健全法律制度,保障节水农业发展.  相似文献   
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