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101.
The presence of Escherichia coli in recreational and potable waters is a major concern to the general public as elevated levels of E. coli suggest the presence of pathogenic bacteria and viruses. Unfortunately, traditional microbial techniques do not allow specific identification of the source of E. coli. This reduces the ability to target management practices that reduce bacterial contamination. In the Finger Lakes region of western New York, USA, wildlife resides in relatively high densities on watersheds dominated by people and dairy farms, and as a result, the sources of fecal degradation of potable and recreational waters are often unknown. In the Conesus Lake watershed, the sources of microbial contamination were assessed using Rep-PCR molecular tools, a method of amplifying repetitive DNA sequences found throughout the E. coli genome to produce distinct fingerprints for a given ecotype. Molecular fingerprints of E. coli isolated from regional populations of cattle, humans, geese and deer were compared to E. coli isolated from stream water samples. Canonical discriminant function analysis indicated that the DNA fingerprints of the original source group isolates were correctly predicted 90.2% of the time. Since land use in the sub-watersheds was dominated by dairy and cash crop farms, it was expected that the majority of E. coli isolated would be identified as cows; however, an unexpectedly high percentage of isolates were identified as wildlife (geese and deer). Geese were the dominant source of E. coli (44.7-73.7% of the total sources) in four sub-watersheds followed by cows (10.5-21.1%), deer (10.5-18.4%), humans (5.3-12.9%) and unidentifiable sources (0.0-11.8%). Management practices intended to decrease the number of cattle or the amount of manure spread in a sub-watershed were reflected in a decrease of E. coli ecotypes associated with dairy cows. 相似文献
102.
Questions of equity, justice, and fairness in the international agricultural adaptation regime have emerged in recent years, prompting interest in regime power dynamics. Here, a three-dimensional conceptual framework of ‘power as domination’ is applied to the UNFCCC adaptation regime. We argue that this ‘power-over’ framing is an important lens through which to view adaptation, a field dominated by ‘power-to’, capacity-based constructs. The framework distinguishes between power-over manifesting through decision-making, agenda setting and preference shaping. Through a literature review we demonstrate that first and second dimension behavioral views of power-over fail to account for the subtle ways in which the interests and preferences of smallholder farmers are unknowingly shaped and restricted within the regime. Potential sources of third dimension preference shaping power are explored in a survey with high-level decision makers involved in National Adaptation Plans (NAP) development in seven countries. The results suggest that several inter-related features of the international agriculture adaptation regime collectively contribute to the shaping of interests and preferences of smallholders: prevailing discourses of uncertainty and the perceived limited capacity of smallholders; the resulting privileged status of ‘expert’ decision makers; the predominance of neoliberal development rationalities; and systemic biases resulting from the nation state as the principle unit of UNFCCC negotiation. These forces lie beyond the explanatory scope of first and second dimensions of power-over and help to explain why stakeholder engagement in adaptation decision making remains superficial in nature and why adaptation responses in agriculture can be considered ‘common and non-differentiated’. We argue for increased awareness of third dimension manifestations and impacts of power in adaptation literature to facilitate the improved participation of marginalized stakeholders in UNFCCC and domestic adaptation decision making forums, to increase the diversity of adaptation options available to smallholders, and ultimately, to improve the attribution of responsibility for adaptation outcomes. 相似文献
103.
Long-term increase in climatic dryness in the East-Mediterranean as evidenced for the island of Samos 总被引:1,自引:0,他引:1
Christian Körner Dimitrios Sarris Dimitrios Christodoulakis 《Regional Environmental Change》2005,5(1):27-36
The Eastern Mediterranean region is among the regions which were predicted to become drier under IPCC climate scenarios. Here, we document a gradual reduction of rainfall and tree growth and the loss of rural springs during the last decades of the twentieth century. Years with severe drought are associated with very low tree growth (dendrochronology) and dry falling of springs as evidenced by interviews with local stakeholders. The paper discusses the consequences of accelerating drought on natural vegetation and agriculture and points at the interaction with fire dynamics and economy, both likely to enhance the drought effect. 相似文献
104.
持续农业,气候变化与有害生物持续治理 总被引:8,自引:0,他引:8
21世纪,随着世界人口的增加,首先将面临着对粮食及其它农产品的需求量的增加。要达到粮食稳定和人类的需求量,其制约的因素很多。本文就气候变化、有害生物的持续治理、对持续农业的影响进行了探讨。 相似文献
105.
分析了农业发展过程中的一系列矛盾及我国在农业持续发展方面与发达国家的差异 ,提出农业发展持续的机制 ,主要由以下几方面内容构成 :人口控制机制 ;资源保护与更新机制 ;环境成本控制机制 ;土地投入机制 ;新技术开发与推广机制。 相似文献
106.
云南省农业自然灾害区划指标之探讨 总被引:7,自引:1,他引:7
自然灾害区划是防灾减灾和灾害科学研究的重要内容,而正确地选取区划指标是进行区划工作的关键环节。本文作为《云南省农业自然灾害区划研究》课题的一部分,在探讨各单项灾害(干旱、洪涝、低温霜冻、风雹、水土流失)区划指标的基础上,提出了综合农业自然灾害区划的基本指标-即“综合农业自然灾害指数”,并对指标进行了分级,为区划工作提供了依据。 相似文献
107.
Does efficient irrigation technology lead to reduced groundwater extraction? Empirical evidence 总被引:1,自引:0,他引:1
Encouraging the use of more efficient irrigation technology is often viewed as an effective, politically feasible method to reduce the consumptive use of water for agricultural production. Despite its pervasive recommendation, it is not clear that increasing irrigation efficiency will lead to water conservation in practice. In this paper, we evaluate the effect of a widespread conversion from traditional center pivot irrigation systems to higher efficiency dropped-nozzle center pivot systems that has occurred in western Kansas. State and national cost-share programs subsidized the conversion. On an average, the intended reduction in groundwater use did not occur; the shift to more efficient irrigation technology has increased groundwater extraction, in part due to shifting crop patterns. 相似文献
108.
Joseph Chung 《Disasters》1987,11(1):40-48
Tropical cyclones and hurricanes have a severe impact on the social and economic activities of affected communities. For small island nations in the Pacific region, the effects can be devastating because of their smallness. FQi and several other countries in the region are vulnerable to such disasters as they are situated in the zone where cyclones occur frequently.
During the last decade, the frequency of natural disasters and their adverse impact on die economic and social development of small nations like Fiji, has aroused awareness mat relief efforts must go beyond immediate "mopping up" operations to those which contribute to attaining longer term benefits through reconstruction and rehabilitation.
The paper outlines the 1985 agricultural rehabilitation program and discusses related issues and problems. 相似文献
During the last decade, the frequency of natural disasters and their adverse impact on die economic and social development of small nations like Fiji, has aroused awareness mat relief efforts must go beyond immediate "mopping up" operations to those which contribute to attaining longer term benefits through reconstruction and rehabilitation.
The paper outlines the 1985 agricultural rehabilitation program and discusses related issues and problems. 相似文献
109.
Financing of wasteland afforestation in India 总被引:2,自引:0,他引:2
India has vast tracts of wastelands, which have been lying barren for ages. Most such lands are physically suitable for growing trees and thus could be put to socially productive uses. However, although usually economically viable, afforestation requires massive initial investment, generally beyond the means of the landowners. Also, government budgetary allocations do not cover current needs. In this situation, institutional credit is required. The National Bank for Agriculture and Rural Development (NABARD) of India has recognized this need and has devised a number of different schemes to provide refinance facilities to individuals and organisations. Although the number of forestry schemes refinanced by NABARD has increased rapidly in the past, they currently constitute only about 1% of the total number of loans sanctioned, and only about 2% of NABARD's cumulative loan disbursement to date. In fact, since 1992, the share of afforestation schemes has declined. A number of factors have been identified as major constraints, including time-consuming and complicated procedures for accessing land; restrictions on harvesting and selling trees; delays in sanctioning and disbursement of bank credit; non-remunerative prices for tree products; and flawed public policies and programmes. This article argues that unless these constraints are overcome, NABARD will not be able to play an effective role in speeding up development programmes in the forestry sector. It further argues that most of the current constraints on institutional credit for wasteland afforestation can be removed or relaxed. Practical strategies are suggested to mobilize more funds and channel more institutional credit for wasteland afforestation in India. 相似文献
110.
Climate forecasts of the total rainfall in the Sudano-Sahelian region of West Africa may have sufficient value to assist in agricultural decision-making at the national, regional and local level. Forecasts are produced in both international and national centres using a variety of techniques. Institutions in Burkina Faso, the focus of the present case study, that are involved in agro-meteorology and agriculture are interested in using forecasts. They have requested many improvements in the forecasts—some of which are beyond the state of the art. The research for the present article, based on interviews with representatives of institutions and following the trail of other agro-meteorological information, confirms the existence of an information network within Burkina Faso that could reasonably well disseminate climate forecasts to interested organizations, farmers, and pastoralists. 相似文献