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731.
ABSTRACT: Water quality and nonpoint source (NPS) pollution are important issues in many areas of the world, including the Inner Bluegrass Region of Kentucky where urban development is changing formerly rural watersheds into urban and mixed use watersheds. In watersheds where land use is mixed, the relative contributions of NPS pollution from rural and urban land uses can be difficult to separate. To better understand NPS pollution sources in mixed use watersheds, surface water samples were taken at three sites that varied in land use to examine the effect of land use on water quality. Within the group of three watersheds, one was predominately agriculture (Agricultural), one was predominately urban (Urban), and a third had relatively equal representation of both types of land uses (Mixed). Nitrogen (N), phosphorus (P), total suspended solids (TSS), turbidity, pH, temperature, and streamflow were measured for one year. Comparisons are made among watersheds for concentration and fluxes of water quality parameters. Nitrate and orthophosphate concentrations were found to be significantly higher in the Agricultural watershed. Total suspended solids, turbidity, temperature, and pH, were found to be generally higher in the Urban and Mixed watersheds. No differences were found for streamflow (per unit area), total phosphorus, and ammonium concentrations among watersheds. Fluxes of orthophosphate were greater in the Agricultural watershed that in the Urban watershed while fluxes of TSS were greater in the Mixed watershed when compared to the Agricultural watershed. Fluxes of nitrate, ammonium, and total phosphorus did not vary among watersheds. It is apparent from the data that Agricultural land uses are generally a greater source of nutrients than the Urban land uses while Urban land uses are generally a greater source of suspended sediment.  相似文献   
732.
Objective: Bicycle riding is increasingly popular in Taiwan, but the number of cyclists injured and cyclists' death rates are both increasing. The aim of this study was to investigate the different characteristics and clinical outcomes of traffic accident–related head injuries among cyclists in urban and rural areas.

Methods: Records of 812 patients (533 urban and 279 rural) admitted to 27 hospitals in Taipei City and Hualien County as the result of a traumatic head injury while bicycling between 1998 and 2013 were retrieved for study. Demographics, details about the accident, protective helmet use, and clinical outcomes were then subjected to analysis.

Results: Urban victims were more likely to be injured during morning and early evening rush hours and rural victims during the day; most urban victims were between 19 and 34 years of age and injured in the slow lane; rural victims tended to be younger or older and were injured in the fast lane (all P ≤.001). Riders who wore a helmet were less likely to suffer loss of consciousness (odds ratio [OR] = 0.31), amnesia (OR = 0.069), neurological disorders (OR = 0.205), or facial fractures (OR = 0.369). Older age, more severe head injuries, and bicycle–motor vehicle collisions influenced the severity of symptoms on admission and the residual effects at discharge.

Conclusions: Differences in the characteristics of injuries in urban and rural areas and the utilization of protective helmets may help government authorities adopt appropriate policies to promote safer and more enjoyable cycling.  相似文献   

733.
农村能源建设滞后制约着经济的发展,尤其是高效而稳定的持续农业的发展。本文从以沼气为纽带的生态农业出发,论述了农村能源建设是实现持续农业的重要前提,对农村整体具有经济,社会,生态效益。  相似文献   
734.
根据岫岩的自然环境特点和自然资源状况,分析了岫岩农村生态环境现状和存在的主要问题,提出了加强农村生态环境建设的主要对策:合理使用化肥、农药,促进土壤养分良性循环;提出深化生态示范区建设的环保对策和资金倾斜政策;加强乡镇企业环境管理,用政府宏观调控职能,控制污染负荷增加;对资源开发项目征收环境资源补偿费,对已污染的土地建立土地恢复基金制度,并提出了环保部门在农村生态环境保护中应尽的职责。  相似文献   
735.
湖北省农村环境调查与分析   总被引:5,自引:0,他引:5  
文章调查分析了湖北省江汉平原、鄂北岗地等部分地区农村的环境状况,并对农民环境意识进行了问卷调查.调查表明,湖北省农村化肥、农药等过量施用十分突出;除鄂西山区外,地表水污染相当严重,塘堰已基本丧失饮用功能;垃圾污染不显著,但秸秆乱垛、垃圾乱倒、粪肥乱堆、畜禽乱跑等现象相当普遍;乡镇企业污染不突出,但应密切关注;农民已有一定的环境意识和要求,也有一定的环境知识;农民最关心的实事是修水泥路,其次为建水厂;农民不仅有改善环境的愿望,也有为之支付部分费用和劳动力的意愿.最后,提出了保护农村环境的建议和对策.  相似文献   
736.
文章调查分析了湖北名江汉平原、鄂北岗地等部分地区农村的环境状况,并对农民环境意识进行了问卷调查。调查表明,湖北名农村化肥、农药等过量施用十分突出;除鄂西山区外,地表水污染相当严重,塘堰已基本丧失饮用功能;垃圾污染不显著。但秸秆乱垛、垃圾乱倒、粪肥乱堆、畜禽乱跑等现象相当普遍;乡镇企业污染不突出,但应密切关注;农民已有一定的环境意识和要求。也有一定的环境知识;农民最关心的实事是修水泥路,其次为建水厂;农民不仅有改善环境的愿望,也有为之支付部分费用和劳动力的意愿。最后,提出了保护农村环境的建议和对策。  相似文献   
737.
抓好农村环境教育   总被引:2,自引:0,他引:2  
解决农村的环境问题,首要的是提高人们的环境意识,加强环境教育。农村环境教育,主要是领导层的教育,对广大农民的教育内容要丰富,形式要多样,要贴近生活要有针对性,政府要有措施作保障。  相似文献   
738.
中国乡村城市化过程中的景观生态学问题与对策研究   总被引:10,自引:1,他引:10  
刘黎明  杨琳  李振鹏 《生态环境》2006,15(1):202-206
城市和乡村的发展共同构成了社会-经济-自然复合生态系统的可持续发展,然而长期以来,重城市轻乡村的发展思想导致了城乡二元结构矛盾不断尖锐。随着经济的高速发展和加入WTO后的国际化冲击,未来的10~20年间,中国将进入一个乡村城市化快速发展的时期,这将使得中国本来紧张的人地关系变得更加严重,资源消耗与环境污染问题日益突出,乡村发展将面临更大的挑战,同时也将是中国乡村发展的重要契机。本文依据景观生态学原理与方法,通过研究乡村城市化进程中乡村景观的组合、结构、功能以及变化中存在的问题,提出了城乡协调、全盘布局和保留自身特色等相应的生态规划治理措施和对策,尽可能使乡村景观格局呈现多样性、异质性,并在功能上表现出稳定性和连续性,最终实现城乡景观和谐发展的局面。  相似文献   
739.
Performance evaluation of two reverse osmosis (RO) desalination plants (DSP) at villages: Melasirupodhu (30 m3 day-1) and Sikkal (50 m3 day-1) in Ramanathpuram district,Tamil Nadu (India) were studied so as to bring out the state-of-art of their operation and maintenance (O&M). Detailedinformation on plant design and engineering, water quality,plant personnel, and cost of O&M was collected for a period ofthree years after commissioning of the two plants. Feed waterwas brackish, the TDS varied in the range of 6500–8500 mg L-1 at Melasirupodhu and 5300–7100 mg L-1 atSikkal villages. The product water quality was observed to begradually deteriorating as the salt rejection by the membranesdecreased with time. The salt rejection was 97–99% atthe time of commissioning of the plants, and came down to89–90% at the end of 3 years of operation. Product water TDS soonafter installation of the plants was excellent and within desirable limits of BIS. After three years of operation, few parameters exceeded the desirable limits, however, they were found to be within permissible limits of BIS. The analyses of thedata showed that both plants were operated only at 30–36% of the design capacity. Plant shut-down due to inadequate and erratic power supply, and plant break-down and inherent delay in repairs due to lack of adequate infrastructure were found tobe the major causes for the low utilization of the plants. Consequently the recurring cost of product water production enhanced to Rs. 25.0/m3 at Melasirupodhu and Rs. 17.5 m-3 at Sikkal, as against the estimated cost of Rs. 15.0/m3 and Rs. 11.0/m3, respectively, as per the design. Over the years, the energy consumption for the product water output increased reflecting higher operational pressures needed with the aging of the membranes.  相似文献   
740.
Chambers R 《Disasters》1982,6(1):21-30
Rapid change In rural Africa raises new policy problems In dealing with mass influxes of rural refugees. Self-settlement in agriculture has become less feasible and is less acceptable now that Its disadvantages are better understood. Organized smallholder settlement can be a better solution where it is economically viable, refugees have freedom of movement, and staff are suitable. But growing land shortage means that Increasing proportions of refugees are being placed in camps. To offset this trend, more attention is suggested to programmes for groups of refugees, categorized by time of arrival, by ability to self-settle or to farm, and by skills and experience. Practically-oriented social science research can contribute to these and other approaches which will require imagination and ingenuity. Solutions to future rural refugee problems should be linked with programmes of social and economic development which will make easier the achievement of humanitarian objectives.  相似文献   
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