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21.
John N. Clarke 《Disasters》2013,37(3):420-441
With the increase in internal conflicts following the end of the Cold War, the scale and scope of the United Nations' work in conflict and post‐conflict environments grew markedly. As a result, the coordination of programming and policy in the transition from relief to recovery has been a central preoccupation of academics and practitioners alike. Intergovernmental bodies such as the United Nations Economic and Social Council (ECOSOC) have made these topics a subject of regular discussion, while some countries have altered their bureaucratic structures to respond more effectively in post‐crisis settings, particularly in cases involving the deployment of national troops. The United Nations Resident Coordinator's Office in Sudan provides a model for other transitional countries and is a useful case study of the broader challenges of post‐crisis programming. Effective coordination structures and planning/programming processes are identified as interdependent prerequisites for ensuring a successful transition from relief to recovery.  相似文献   
22.
Rob Kevlihan PhD 《Disasters》2013,37(4):579-603
The impact of conflict, particularly conflict arising during civil wars, on the provision of healthcare is a subject that has not been widely considered in conflict‐related research. Combatants often target health services to weaken or to defeat the enemy, while attempts to maintain or improve health systems also can comprise part of counter‐insurgency ‘hearts‐and‐minds’ strategies. This paper describes the dynamics associated with the provision of health services in Malakal, an important garrison town in South Sudan, during the second Sudanese civil war (1983–2005). Drawing on the concepts of opportunity hoarding and exploitation, it explores the social and political dynamics of service provision in and around the town during the war. These concepts provide a useful lens with which to understand better how health services are affected by conflict, while the empirical case study presented in the paper illustrates dynamics that may be repeated in other contexts. The concepts and case study set out in this paper should prove useful to healthcare providers working in conflict zones, including humanitarian aid agencies and their employees, increasing their understanding of the social and political dynamics that they are likely to face during future conflict‐related complex emergencies.  相似文献   
23.
东洞庭湖保护区1989~1998年水禽栖息地动态研究   总被引:7,自引:0,他引:7  
栖息地的改变是全球生物多样性存在的最大威胁。利用卫星遥感技术和地理信息系统的空间分析功能,从景观尺度上研究了东洞庭湖自然保护区1989~1998年越冬水禽栖息地的动态变化特征,结果表明:1989~1998年水体、泥滩地、草滩地和水田等水禽适宜栖息地的面积在减小,破碎化程度有所增加,而芦苇滩地、旱地、林地、建成区这几类水禽分布较少栖息地类型的面积和破碎化程度的变化正好相反;近10年来水禽栖息地的变化比较明显,其中草滩地演变为芦苇滩地及水田改为旱作农田的变化最为突出,变化的面积分别占整个保护区面积的10.66%和6.13%。这些变化趋势意味着研究区近10年来水禽的适宜栖息地在退化。针对变化的原因,论文还对该区域生物多样性的保护与栖息地管理提出了可行的建议。  相似文献   
24.
本文较系统研究了扬子型铜矿床中有代表性的菱铁矿、胶黄铁矿、黄铁矿、磁黄铁矿、磁铁矿、黄铜矿及部分脉石矿物的稀土元素组成及特征,总结了展状矿石中和矽卡岩矿石中矿物稀土元素组成的特点及二者之间存在的明显差别,从一个方面探索扬子型铜矿床的成因。  相似文献   
25.
A2/O工艺强化反硝化除磷体系中微生物特性分析   总被引:1,自引:0,他引:1  
为了更直观地认识反硝化除磷体系中生物脱氮除磷机理及运行状态,本文尝试了对A2/O工艺强化反硝化除磷体系在稳定运行期的活性污泥采取直接染色的手段,观察聚-β羟基丁酸(PHB)和聚磷酸盐(Poly-P)的沿程变化状况,同时结合活性污泥的电镜扫描图像,考察该系统的微生物菌群特征.试验结果表明,在厌氧阶段,微生物细胞内PHB的量大幅提高,上清液中磷酸盐的含量上升,聚磷酸盐含量明显下降,粒径为1~1.5μm、呈球状和棒状的菌群构成的葡萄状细胞簇占居优势;在缺氧阶段,微生物细胞内PHB的量下降,上清液中磷酸盐含量下降,聚磷酸盐含量上升,粒径为0.5~1μm的椭球菌与1.0~1.5μm的球杆菌占优势;在好氧阶段,微生物细胞内PHB的量较低或接近零,上清液中磷酸盐的含量接近零,聚磷酸盐含量明显上升,此时粒径1.0~1.5μm的球菌以单个或成对出现,球菌不再饱满,呈现接近消失的状态.相比之下,单纯的脱氮系统则不存在上述微生物特性的变化.图8参12  相似文献   
26.
Ninety-nine human blood samples were collected from the riverine region of northern Sudan and the traditional and mechanized rain-fed areas of western and eastern Sudan, representing areas of limited pesticide use in Sudan. Blood samples were analyzed for organochlorine pesticides by gas liquid chromatography (GLC) followed by electron-capture detection (ECD). p,p′-DDE (a metabolite of DDT), heptachlor epoxide, β-hexachlorocyclohexane (β-HCH), and dieldrin were detected in all locations surveyed. The level of total organochlorine burden was highest in the traditional rain-fed area, followed by the mechanized rain-fed area, and the riverine area. A highly significant correlation was observed between total organochlorine blood burden and the age of the donors (r = 0.608**).  相似文献   
27.
28.
段伟 《灾害学》2003,18(3):91-96
认为东汉王景治河后500多年黄河下游决溢次数、规模均逊于西汉时期及唐以后各代,主河道变迁亦少,可谓相对安流。其原因在于王景能根据河流规律,因势利导,扩大了黄河行洪能力,巩固了河堤,河道较为顺直;在王景之后,政府的治河机构进一步加强,巩固河堤的工作得以继续进行;相对西汉时期,这一时期气候寒冷,黄河年径流量大为减少,消弱了致灾因子;黄河中游地区植被得到一定程度的恢复。  相似文献   
29.
This article focuses on agricultural production in lift irrigation schemes along the White Nile in the Sudan. A comparison is drawn between the theoretical forecast and actual practical experience regarding the feasibility of transferring management from government-run parastatal organizations to private farmer organizations. Although the theoretical model indicates that farmers should be able to cover the cost of managing the river lift irrigation systems, field data show, however, that farmers growing wheat are barely able to break even. Even assuming a doubling of the present wheat yields, the cash surplus earned would only suffice for fuel to operate the pumps. Under these circumstances, it is not surprising that, contrary to government expectations, the private sector has been unenthusiastic about taking over management of White Nile river lift schemes. The lessons that emerge from this study indicate that unplanned and rapid withdrawal of state management can lead to negative results. The transfer of management responsibility for the river pumps does not appear to influence economic performance considerably, which depends on the wider context of the country's economic, political and institutional environment, within which the agricultural sector functions.  相似文献   
30.
As the number of proposals to divert streamflow for power production has increased in recent years, interest has grown in predicting the impacts of flow reductions on riparian vegetation. Because the extent and density of riparian vegetation depend largely on local geomorphic and hydrologic setting, site-specific geomorphic and hydrologic information is needed. This article describes methods for collecting relevant hydrologic data, and reports the results of such studies on seven stream reaches proposed for hydroelectric development in the eastern Sierra Nevada, California, USA. The methods described are: (a) preparing geomorphic maps from aerial photographs, (b) using well level records to evaluate the influence of streamflow on the riparian water table, (c) taking synoptic flow measurements to identify gaining and losing reaches, and (d) analyzing flow records from an upstream-downstream pair of gages to document seasonal variations in downstream flow losses. In the eastern Sierra Nevada, the geomorphic influences on hydrology and riparian vegetation were pronounced. For example, in a large, U-shaped glacial valley, the width of the riparian strip was highly variable along the study reach and was related to geomorphic controls, whereas the study reaches on alluvial fan deposits had relatively uniform geomorphology and riparian strip width. Flow losses of 20% were typical over reaches on alluvial fans. In a mountain valley, however, one stream gained up to 275% from geomorphically controlled groundwater contributions.  相似文献   
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