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391.
392.
兴文石林是喀斯特岩溶地质风景名胜区兴文石海的中心景区,喀斯特岩溶山地的生态环境具有一定脆弱特性。随着旅游业的不断发展,景区加大了开发力度,可能导致景区脆弱性的加剧,为了保证在旅游开发中能对景区重要的地质资源进行更好地保护。采用生态脆弱区评级指标厦权重值评分法对兴文石林的10个主蒂点进行了研究,分析得出,兴文石林存在轻生态脆弱性、中生态脆弱性和强生态脆弱性三种梯度趋向,其中,脆弱性最强区域面积达到2平方公里的面积,这些区域分布在景区的边缘地带,因此。要实现旅游资源的可持续利用,必须对强生态脆弱性区域实行禁游和实行退耕还林等措施,以防止脆弱区域的扩大和脆弱性加剧。 相似文献
393.
William J. de Groot Robert D. Field Michael A. Brady Orbita Roswintiarti Maznorizan Mohamad 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):165-180
Forest and land fires in Southeast Asia have many social, economic, and environmental impacts. Tropical peatland fires affect
global carbon dynamics, and haze from peat fires has serious negative impacts on the regional economy and human health. To
mitigate these fire-related problems, forest and land management agencies require an early warning system to assist them in
implementing fire prevention and management plans before fire problems begin. Fire Danger Rating Systems (FDRS) were developed
for Indonesia and Malaysia to provide early warning of the potential for serious fire and haze events. In particular, they
identify time periods when fires can readily start and spread to become uncontrolled fires and time periods when smoke from
smouldering fires will cause an unacceptably high level of haze. The FDRS were developed by adapting components of the Canadian
Forest Fire Danger Rating System, including the Canadian Forest Fire Weather Index (FWI) System and the Canadian Forest Fire
Behavior Prediction (FBP) System, to local vegetation, climate, and fire regime conditions. A smoke potential indicator was
developed using the Drought Code (DC) of the FWI System. Historical air quality analysis showed that the occurrence of severe
haze events increased substantially when DC was above 400. An ignition potential indicator was developed using the Fine Fuel
Moisture Code (FFMC) of the FWI System. Historical hot spot analysis, grass moisture, and grass ignition studies showed that
fire occurrence and the ability for grass fires to start and spread dramatically increased when FFMC > 82. The Initial Spread
Index (ISI) of the FWI System was used to develop a difficulty of control indicator for grassland fires, a fuel type that
can exhibit high rates of spread and fire intensity. This ISI-based indicator was developed using the grass fuel model of
the FBP System, along with a standard grass fuel load and curing level estimated from previous Indonesian studies. Very high
fire intensity is expected in grasslands when ISI ≥ 6. To provide early warning, the FDRS identifies classes of increasing
fire danger as the FFMC, DC, and ISI approach these key threshold values. The Indonesian FDRS is now operated nationally at
the Indonesian Meteorological and Geophysical Agency. The Malaysian Meteorological Service operates the Malaysian FDRS and
displays regional outputs for the Association of Southeast Asian Nations. The FDRS are being used by forestry, agriculture,
environment, and fire and rescue agencies to develop and implement fire prevention, detection, and suppression plans. 相似文献
394.
S. Suyanto 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):67-74
One of the social phenomena that have arisen in Indonesia in the post-Reformasi period (mid-1998) is the increase in land tenure conflicts between local communities and tree plantation companies, and between
local communities and the forestry department. Land tenure conflicts often trigger forest and land fires, which is both a
symptom and a cause of increasing conflict over tenure and use rights. If the tenure issue is not appropriately addressed,
it will continue to result in unwanted fires and forest degradation, related smoke and gas emissions, and environmental and
economic losses.
A recent study in Sumatra revealed that, in many cases, (1) tenure conflicts between companies and communities, resulting
from past government policies and practices, often trigger forest and land fires because of frustrations by the communities
of being unable to have their claims heard in a fair and transparent judicial system; and (2) even with the use of military
force, forest policy and management has largely failed to protect forest resources when local communities were not involved.
The nature of the partnership between communities and companies in land use development is also an important factor in influencing
the incidence and control of fire. 相似文献
395.
本文介绍了南岳森林土壤与母岩的化学性状,以了解气候和植被对土壤的影响;介绍了土壤有机质的作用、含量、分布;讨论了影响土壤有机质含量的因素并给出了循环模型。 相似文献
396.
397.
398.
200 years of sustainability in forestry: Lessons from history 总被引:4,自引:0,他引:4
K. Freerk Wiersum 《Environmental management》1995,19(3):321-329
Since the end of the 1980s the concept of sustainable development has gained general acceptance, but much uncertainty still
exists on how to operationalize this concept. In forestry the concept of sustainability has been an accepted principle since
the 18th century. The experiences with its application in forestry may contribute towards obtaining a better insight into
the implications and operational significance of the concept of sustainability. This article describes the history of sustainability
in forestry, including the various social values on which its interpretation has been based. The original principle of sustained
yield has gradually been broadened to a more inclusive principle of sustainable forest management. The dynamics in social
valuation of forest resources resulted in various attempts at practical operationalization of the principle. Notwithstanding
200 years of efforts to operationalize the concept of sustainability, its exact application in forestry remains troublesome.
Three lessons are drawn: (1) the need to recognize the different nature of ecological limits and social dynamics, (2) the
role of dynamic social values with respect to forest resources, and (3) the significance of operational experiences in trying
to attain sustainability within a concrete context. 相似文献
399.
Warren B. Cohen John D. Kushla William J. Ripple Steven L. Garman 《Environmental management》1996,20(3):421-435
Aerial photography has been routinely used for several decades by natural resource scientists and managers to map and monitor the condition of forested landscapes. Recently, along with the emergence of concepts in managing forests as ecosystems, has come a significant shift in emphasis from smaller to larger spatial scales and the widespread use of geographic information systems. These developments have precipitated an increasing need for vegetation information derived from other remote sensing imagery, especially digital data acquired from high-elevation aircraft and satellite platforms. This paper introduces fundamental concepts in digital remote sensing and describes numerous applications of the technology. The intent is to provide a balanced, nontechnical view, discussing the shortcomings, successes, and future potential for digital remote sensing of forested ecosystems. 相似文献
400.
The Delphi approach to the mediation of environmental disputes 总被引:1,自引:1,他引:1
Environmental disputes, in many countries, have taken on a ritualistic character. Their persistence, even after prolonged analysis and debate, suggests that they result from ideological rather than factual differences. Since no single ideological position holds a monopoly on the truth, effective environmental management would seem to require an integration of views, the problem being how to achieve this. One approach to this problem is illustrated in this article. Two factions in the spruce budworm dispute in New Brunswick, Canada, were engaged in a mediation exercise using the Delphi method. Details of the design and execution of this form of mediation are provided, together with an evaluation of the Delphi's effectiveness in this context. 相似文献