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41.
2 semiarid irrigated area with salt-affected soils. The available soil map is at 1:100,000 scale and its mapping units are
used for the land evaluation with the FAO framework. These data are then elaborated using the index value method. This procedure
gives a map of land evaluation units and a table that rates the productive potential of these units for six crops: alfalfa,
barley, maize, rice, sunflower, and wheat. 相似文献
42.
Gladys Mutangadura 《Natural resources forum》2007,31(3):176-187
The study presented in this article used a combination of key informant interviews and a review and synthesis of existing country level literature to identify the major sources of land tenure insecurity in six Southern African countries: Botswana, Lesotho, Malawi, Mozambique, South Africa, and Zambia. Findings reveal that the main causes of land tenure insecurity experienced in Southern Africa include lack of land rights of minority groups, unclear or overlapping land rights, overcrowding, land alienation into leasehold, insecurity of farm workers and farm labour tenants, inappropriate and exploitative administrative practices, land encroachment and illegal settlers and limited women's land rights. The article presents a summary of land tenure security related initiatives that the study countries have or are in the process of adopting. Analysis of these initiatives shows that tenure reforms have focused on changing the law and rules but little has been done to translate new laws into implementable programs; capacity building; prioritization of resources to support tenure reform; provision of complementary policies and incentives; addressing HIV/AIDS‐land tenure related problems; and monitoring and evaluation. The paper contends that these policy issues should be addressed in order to ensure realization of land tenure security for all. 相似文献
43.
A land suitability model was developed to provide the planner with a quantitative tool for assessing the environmental limitations on proposed land-use changes in the area surrounding Lake Monroe in southern Indiana. The model incorporates a weighting procedure that allows the environmental evaluation of a decision to convert the present land use to another category. The data base for the model was assembled by a multidisciplinary team. A case study is included, which illustrates the advantages and limitations of the land suitability model as it is applied to the evaluation of a site for the Alumni Family Camp. 相似文献
44.
45.
Edwin T. Engmun 《Journal of the American Water Resources Association》1974,10(3):512-521
ABSTRACT: According to a concept known as partial area hydrology, watershed areas are separated into hydrologically active and passive subareas. The literature relating to the development of the partial area concept is reviewed briefly and the relationship of partial area hydrology to geology, soils, and micrometeorology is illustrated. The potential application of partial area hydrology is discussed with respect to present hydrologic techniques, future hydrologic models, urban hydrology, water quality, and water management. Suggestions for identifying and delineating the contributing areas are discussed. 相似文献
46.
Tiziano Gomiero Davide Pettenella Giang Phan Trieu Maurizio G. Paoletti 《Environment, Development and Sustainability》2000,2(2):119-142
Vietnam, in the ongoing transition to market economies, has to cope with high rural poverty and a dramatic process of forest loss and environment degradation, particularly in the mountainous regions. The government considers rural poverty as the main cause of environment degradation, associated with slash-and-burn cultivation and to an unclear definition of property rights on forest land. In 1993, the government launched a Forest Land Allocation programme aiming to lease forest lands to individual households and, on this basis, to solve food security problems, halt the increasing environment degradation and preserve the remaining forests.To evaluate the results of this land reform policy, two upland pilot communes have been intensively monitored. The environmental and economic impacts of the forest land reform allocation in the two study areas are presented, after providing a background on the Vietnamese situation of mountain zones. On the basis of these findings, it is discussed as to whether the current forest land allocation process may actually promote local development and natural resources conservation, and under what conditions. Deforestation problems must be tackled also with new macroeconomic policies (e.g. credit programmes to support sustainable agriculture practices) and social policy (e.g. reduction of demographic pressure), together with the reform of the State institutions (e.g. State Forest Enterprises) involved in management of the forest areas. 相似文献
47.
Jon D. Unruh 《Natural resources forum》2008,32(2):103-115
Land tenure plays a primary role in sustainable development efforts. However armed conflict and its repercussions reconfigure the network of social relations upon which all land tenure systems depend. In post‐conflict settings new laws have the opportunity to address tenure issues in the context of what people are already doing ‘on the ground’, with a view to moving from the fluidity of post‐conflict situations to a more solidified and peaceful social and legal environment. However there exists a lack of tools to analyze postwar land tenure and the prospects for reconstituting tenure systems to support recovery and development. This paper uses the Sustainable Livelihoods framework to examine postwar land tenure issues in order to draw out latent opportunities within emergent informal smallholder tenure constructs which may have utility in the reconstitution of national tenure systems. 相似文献
48.
Kenneth R. Krach Benjamin R. Burns Baikun Li Alison Shuler Charles Cole Yuefeng Xie 《Water, Air, & Soil Pollution: Focus》2008,8(3-4):369-378
Over three million dry metric tons of biosolids produced in the United States are land applied as Class B. Lime stabilization
is employed for biosolids treatment at approximately 20% of the wastewater treatment plants because it is a simple and inexpensive
process. During lime stabilization, the pH of sewage sludge is raised above 12 for pathogen inactivation and odor reduction.
Lime dose and mixing have been found to greatly reduce odor generation from lime stabilized biosolids. A better quality biosolids
product is less likely to create public opposition to land application programs. In this study, land application tests using
Class B biosolids were conducted in order to determine whether better mixing can reduce odor generation during the land application
of lime stabilized biosolids. The mixing quality of a treatment plant’s lime stabilized biosolids was improved by relocating
the lime addition point, which prolonged the mixing time and produced a better mixed biosolids product. Based on field observations
of land application, the poorly mixed biosolids were more odorous and offensive prior to incorporation. However, once incorporated
into the soil, there was no appreciable odor difference between the biosolids. Another land application study was conducted
to assess the odor of unincorporated Class A biosolids and compare it with incorporated Class A biosolids with the soil. 相似文献
49.
科尔沁沙地生态环境质量综合评价 总被引:1,自引:0,他引:1
基于研究区2000年土地利用图形数据、土地沙漠化监测数据、环境状况公报数据以及统计年鉴数据,采用中华人民共和国环境保护行业标准《生态环境状况评价技术规范(试行)》HJ/T192—2006)规定的生态环境状况评价的指标体系和计算方法。从旗、县尺度上对科尔沁沙地的生态环境状况进行综合评价。结果表明:2000年科尔沁沙地各旗县的生物丰度指数为22.01-37.96。植被覆盖指数为25.20~45.86,水网密度指数为22.51—30.97。土地退化指数为1.47—21.06。环境质量指数为57.98~59.84,综合生态环境质量指数为25.28~33.25。根据国家生态环境状况分级标准判断.该区域生态环境状况属于较差级别.意昧着该区域植被疆盖度较差。严重干旱少雨.物种较少。存在着明显限制人类生存的因素。 相似文献
50.
Several international initiatives, including the European Biodiversity Strategy to 2020, promote the identification and mapping of ecosystems as basic tools for the conservation of biodiversity and related services. On coarse scales, the spatial representation of ecosystems is usually based on broad land cover categories that largely overlook important ecological and biogeographic features of the biotic communities they are meant to exemplify. This paper presents a nationwide ecosystem mapping approach that promotes a degree of thematic detail, which is more suited than that found in the continental maps to meeting biodiversity conservation targets in Italy. The approach is based on the rationale that current and potential vegetation cover are valuable proxies for outlining ecosystems. The resulting Ecosystem Map of Italy includes 43 types of forest ecosystems instead of the 5 woodland, forest and other wooded land types recognized at the European level. We outline the expected advantages of this enhanced thematic detail for a number of conservation purposes and highlight how the resulting maps may help to meet biodiversity conservation targets at the national level. In particular, we refer to the assessment of conservation status, the definition of restoration priorities, the planning of green infrastructure and the identification of collapse risks for the ecosystems identified. Comprehensively, the definition, characterization and assessment of ecosystem types represent the carrying structure of the recently launched national system of natural capital accounting. 相似文献