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201.
I offer a very qualified argument to the effect that rights are grounded in a certain sort of prejudice that privileges individualistic and perhaps masculinist ways of thinking about moral life. I also propose that we look carefully at other conceptions of social ontology and moral life, including the much discussed care conception.  相似文献   
202.
The National Forest Management Act (1976) specifies that multiresource inventories be conducted to provide baseline data for development and, later, monitoring of national forest management plans. This mandate entails the most ambitious and complex resource planning effort ever attempted. In this paper we evaluate the structure and use of current inventory-monitoring programs and recommend a framework for gathering data to improve national forest planning. Current national guidelines are general and provide only basic directions to forest-level planners. Forest inventories have traditionally concentrated on timber. Although these inventories are often well designed, the questions we are now asking about forest resources have outgrown these methods. Forest management is impeded by general confusion over definitions of resources and the interactions among them. We outline a simple classification scheme that centers on identification of basic ecosystem elements that can be readily measured. Furthermore, spatial and temporal scales must be considered in the design of inventory-monitoring programs. The concept of ecological indicators is reviewed, and caution is advised in their use. Inventory-monitoring programs should be goal-directed and based on as rigorous a statistical design as possible. We also review fundamental issues of variable selection, validation, and sampling bias. We conclude by developing a flexible inventory-monitoring program that is designed to provide information on individual characteristics of the environment, rather than being based on fixed definitions of resources.  相似文献   
203.
ABSTRACT: Because of its importance and the perceived inability of private sector sources to meet water demands, many countries have depended on the public sector to provide water services for their populations. Yet this has resulted in many inefficient public water projects and in inadequate supplies of good quality and reliable water. Decentralization of water management, including the use of water markets, cannot solve all of these water problems, but it can improve the efficiency of water allocation. When given adequate responsibility and authority, water user associations have effectively taken over water management activities at a savings to tax payers. Moreover, water markets add the potential benefit of improving water efficiency within a sector as well as providing a mechanism for reallocating water among sectors. The key question involves developing innovative mechanisms for reducing the transaction costs of organizing water users and of making water trades. Water rights need to be established which are recorded, tradable, enforceable, and separate from land if markets are to operate effectively. Also, institutions are needed that effectively resolve conflicts over water rights, including third party impacts and water quality concerns.  相似文献   
204.
ABSTRACT: Both catchment experiments and a review of hydrologic processes suggest a varying effect of forest harvest on the magnitude of peak flows according to the cause of those peak flows. In northwestern Montana and Northeastern Idaho, annual maximum flows can result from spring snowmelt, rain, mid-winter rain-on-snow, or rain-on-spring-snowmelt. Meteorologic and physical data were used to determine the cause of annual maximum flows in six basins which had the necessary data and were smaller than 150 mi2. Rain-on-spring-snowmelt was the most frequent cause of annual maximum flows in all six basins, although there was a strong gradient in the magnitude and cause of peak flows from southwest to northeast. Less frequent mid-winter rain-on-snow events caused the largest flows on record in four basins. Mid-winter rain-on-snow should be distinguished from rain-on-spring-snowmelt because of differences in seasonal timing, the relative contributions of rain vs. snowmelt, and the projected effects of forest harvest. The effects of mixed flood populations on the flood-frequency curve varied from basin to basin. Annual maximum daily flows could not be reliably predicted from rainfall and snowmelt data.  相似文献   
205.
ABSTRACT: Three forest watersheds were isolated by roads in poorly drained flatwoods of Florida. After 12 months of baseline calibration the forest in one watershed was harvested and regenerated with minimum disturbance, in the second watershed with maximum disturbance from common practices, and in the third watershed left intact as a control. Water yields from the maximum treatments increased a significant 250 percent while that from the minimum treatments increased 117 percent as compared to the control. Weed vegetation remaining after the minimum treatment continued significant water use. The water yield increases lasted only for one year. Water quality was reduced by both treatments with the most effect immediately after the maximum disturbance. Absolute levels of suspended sediments, potassium, and calcium remained relatively low. The maximum treatment caused significant changes in net cation balances only for one year. The information shows relative little effect of silvicultural practices in flatwoods on water quality as compared to data from upland forests. Water yield increases may be manipulated by the degree of harvest and weed control practices.  相似文献   
206.
207.
生态开发福建非木质森林资源   总被引:5,自引:0,他引:5  
森林生态系统中具有丰富的非木质资源,生态开发这类资源可以缓解林业发展的压力,并为山区经济提供新的动力。文章分析了福建非木质森林资源的开发现状、机遇及进一步发展的阻碍因素,并给出了政策建议。  相似文献   
208.
林亦曦 《林业劳动安全》2002,15(3):37-38,40
论述了在新形势下国有林场“三工”安全管理存在的问题,提出了坚持以人为本、以理服人、以情感人、加强企业安全文化建设的“三工”安全管理新机制。  相似文献   
209.
分析了新形势下单纯依赖专业森林消防队伍扑救森林火灾的不足与问题,提出了有偿扑火构想与保证措施。  相似文献   
210.
基于传热分析的林火蔓延特性研究   总被引:4,自引:1,他引:4  
计算了水平流动的热烟气与大乔木、小乔木、灌木主干及大乔木树叶间的强制对流传热;垂直上升流动的热烟气与各类林木的纵向自然对流、纵向强制对流传热;以及烟气对各类林木的辐射传热。分别比较了它们的热流密度和总换热量。讨论了烟气流速、温度、林木尺寸等因素对换热的影响。在此基础上,对不同林木的火险特性进行了预测。  相似文献   
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