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961.
长江三角洲耕地资源态势与保护对策 总被引:20,自引:7,他引:13
长江三角洲是我国东部沿海经济最发达的地区,在全国占有十分重要的经济地位。随着经济的发展,资源与环境发生了严重的问题,特别是近年来耕地资源锐减,而后备耕地资源却短缺,人地人粮矛盾更加尖锐,已成为影响这一地区农业持续发展的重要因素。本文分析了这一地区的经济特点与耕地资源的变化态势,并提出了相应的耕地保护措施。首先,要严格控制非农用地,确保基本农田,其次要采用经济手段,建立保护耕地的经济机制;此外,还要 相似文献
962.
资源工程体系建设探讨——以三峡库区坡地资源开发保护体系建设为例 总被引:2,自引:1,他引:1
申元村 《长江流域资源与环境》1998,(2)
资源工程是实现社会经济发展的基本途径。资源开发体系和保护体系建设是构成资源工程体系的主要内容。文章阐述了如何设计一个资源开发和保护体系的总体思路(包括原则、目标、内容、行动、效益评估),并以长江三峡库区坡地资源利用保护为例,通过植物篱农林复合技术,使水土流失和环境退化基本得到了控制,经济产出比纯柑桔系统和纯粮食作物系统分别高出1/5和1/4,成为开发与保护融为一体、经济和生态相互促进的技术。这一技术值得在中国东部湿润半湿润区域推广。 相似文献
963.
Indigenous people and mineral taxation regimes 总被引:1,自引:0,他引:1
Ciaran O'Faircheallaigh 《Resources Policy》1998,24(4):187-198
Indigenous people in a number of major mineral-producing countries have established a substantial and growing capacity to tax mineral resources extracted from their traditional lands. However, almost no analysis has been conducted regarding the conceptual and practical issues involved in designing mineral taxation regimes for use by indigenous people. The general literature on mineral taxation is of limited relevance because basic assumptions it makes regarding the nature of the taxing authority (national or state governments) do not apply to indigenous peoples. This article discusses some key characteristics of indigenous communities as they relate to taxation of mineral resources. Against this background, it identifies a number of approaches to mineral taxation which might be utilized by indigenous groups and which acknowledge the specific constraints and circumstances they face while at the same time recognizing their need to attract and maintain investment on their traditional lands. It also reviews the inter-relationship between indigenous and state or governmental tax regimes. 相似文献
964.
陕南秦巴山地农业资源立体专业化开发利用 总被引:4,自引:0,他引:4
本文对秦巴山地农业环境特点、资源构成和分异规律进行了系统分析,提出了农业地域专业化开发利用的原则和模式. 相似文献
965.
异地开发是农村剩余劳动力转移的重要模式 总被引:2,自引:0,他引:2
本文阐述了异地开发在农业方面的4点作用和农村剩余劳动力转移的3种基本模式。结合我国国情,指出异地开发是当前我国农村剩余劳动力转移的重要模式,它具有投入小、见效快、收益大的特点。建议政府组织开展有关实施异地开发的政策和措施等问题的研究,把异地开发工作引向深入。 相似文献
966.
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968.
For communicating data on the state of the environment to policy makers, various integrative frameworks are used, including
regional integration. For this kind of integration we have developed two related ecological regionalizations, ecoregions and
ecodistricts, which are two levels in a series of classifications for hierarchically nested ecosystems at different spatial
scale levels. We explain the compilation of the maps from existing geographical data, demonstrating the relatively holistic,
a priori integrated approach. The resulting maps are submitted to discriminant analysis to test the consistancy of the use
of mapping characteristics, using data on individual abiotic ecosystem components from a national database on a 1-km2 grid. This reveals that the spatial patterns of soil, groundwater, and geomorphology correspond with the ecoregion and ecodistrict
maps. Differences between the original maps and maps formed by automatically reclassifying 1-km2 cells with these discriminant components are found to be few. These differences are discussed against the background of the
principal dilemma between deductive, a priori integrated, and inductive, a posteriori, classification. 相似文献
969.
Margot W. Garcia 《Environmental management》1989,13(5):583-592
The National Forest Management Act and National Environmental Policy Act require the use of an interdisciplinary team (ID team) to do integrated resource planning for the National Forests and the concurrent environmental analysis. A survey sent to all National Forest planning officers (82% response) reveals the composition of the ID teams used in integrated resource and land management planning. More than half the National Forests ID teams met NEPA and NFMA compositional requirements. National Forest planners recount their experiences with these ID teams. Despite frustrations with many aspects of the ID teams, the planners strongly support the idea that ID teams are an important part of the land-use planning process and think that their use leads to better National Forest integrated resource plans. 相似文献
970.
A first alternative for estimating the physical carrying capacities of natural areas for recreation 总被引:2,自引:0,他引:2
Utilizing an adaptation of the Universal Soil Loss Equation, this article discusses a method for approximating the physical carrying capacity of natural areas for outdoor recreation. Classification of forested woodland and field environments is based upon the conversion of ground cover coefficients to the percentage of ground cover required to maintain soil productivity over time. Four canopy types, three canopy densities, and two general types of ground cover are recognized in the equation as well as soil characteristics, topographical variations, and rainfall velocities and intensities. The method requires that the areal distribution of soils occurring within natural areas be mapped. Approximations will vary according to the intensity of the planning desired, and may range from a general classification of large land areas to highly site-specific evaluations. Data generated from over 40 years of cooperative research form the basis for classifying natural areas according to their relative physical capacities to accommodate outdoor recreation. 相似文献