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451.
ABSTRACT: Public investments in water resource development projects are continually under scrutiny in terms of economic, environmental, and social impacts. Results of an analysis of a water development project that supplies irrigation water in Idaho are discussed in terms of the impact on income distribution and income growth 44 to 64 years after the project was initiated. Gini ratios for the rural farm population of these counties were consistently lower than they were for the United States as a whole and for the state of Idaho. In addition, income distributions tended to become more equitable over time in the water project counties. Rural farm population income growth rates were found to be similar to those for the nation as a whole. Some of the reasons for these results may be related to the tendency for income distribution to become more equitable as income increases, and the fact that average farm size is relatively small.  相似文献   
452.
ABSTRACT: During the past 15 years a number of methods have been developed that purport to evaluate the amenity values of rivers. Most methods are designed to identify the physical, biological, cultural, and esthetic features of a river or river corridor that are conducive to recreation, preservation, and other amenity values. This paper reviews and comments on 13 methods that evaluate amenity values. The methods are reviewed and discussed under three general headings: River Recreation Potential Evaluation, River Esthetic Evaluation, and River Preservation Evaluation. A final section of the paper identifies areas where improvements and further research are needed.  相似文献   
453.
454.
Bogs are of interest to outdoor recreationists, but little information exists concerning how recreation resource managers might manage these areas to enhance visitor benefits. This study evaluates bog visitor characteristics and experiences, visual preferences, and reasons for visiting. Implications for recreational resource management of bogs include the location and design of boardwalk trails and management of understory vegetation to meet the visual preferences and motives of bog visitors.  相似文献   
455.
ABSTRACT: Decisionmaking associated with the Nation's 1.7 billion acres of forest and range land has become increasingly complicated because of the rise in competition for resource use and in the awareness of environmental and social effects. This system analysis approach uses four models to synthesize pertinent masses of information into measures of economic, environmental, and social impacts. The system results can be used to help evaluate alternative national programs. The models are:
456.
Farmers from four irrigation districts in Texas and California were questioned about water conservation practices they are now using, those they plan to adopt, and potential incentives that government might offer to induce still further water conservation on their part. While responses differed somewhat from place to place and among individual farmers, the general results were: a) farmers reported that “water conservation” is not new to them, it is something they practice regularly; b) recent innovations such as laser controlled land leveling devices have permitted some substantial water use reductions in recent years; and c) even greater incentive mechanisms that government could provide and that farmers would accept as useful incentives, such as long term low interest loans for water saving equipment, would probably not be able to reduce water use in agriculture much further than 15 percent below current levels. It is recommended nonetheless that Federal agencies and local water districts and individuals should nonetheless pursue water conservation training and education programs, demonstrations of conjunctive use and water banking opportunities for water saving, and increased loan programs for installation of water saving equipment.  相似文献   
457.
ABSTRACT: The effectiveness of water conservation policies on reduction of water consumption was evaluated by use of a multiple regression predictive model. Data were obtained from eight Iowa communities, with regard to water consumption and water conservation policies adopted during the drought of 1977. The proposed model, which takes precipitation, temperature, month effects, and uniqueness of communities into account, is considered superior to the use of simple percent changes in evaluating the significance of reduction in water consumption due to conservation efforts. Among the variety of policies reviewed, mandatory policies with per capita restrictions were found to be most effective. However, voluntary conservation policies also resulted in significant reduction in some communities located in close proximity to other communities with severer water shortages. High credibility of local governments as to water shortage information was singled out as the most important factor in successful conservation by water resource policymakers of these communities. Use of the proposed predictive model for water consumption was demonstrated. Recommendations regarding future water conservation were made.  相似文献   
458.
Thousands of individuals throughout the world are now users of satellite data. Hundreds of satellites have been launched—military, navigation, communications, educational, weather, and earth resources. One of the weather satellites (the SMS/GOES) and the NASA earth resources mapping satellite (Landsat) are the subjects of this article. Data from these systems have been highly cost beneficial, not only in the United States, but in developed and developing nations all over the globe as well. There is an increasing demand both for data and for training in data use.Data samples are shown and applications are discussed. Strong reference is made to the value of the digital computer in natural and man-made features mapping and monitoring. Procedures for acquiring NASA data are explained so that the reader may order data for his home region, or for other regions throughout the world which are of interest for their agriculture, forestry, hydrology, marine resources, geology, or land use. The cost of data is incredibly low; some products cost as little as three dollars.Also discussed are the remotely based data-collection platforms that acquire ground or water data daily and relay results to the NASA Landsat or to the NOAA SMS/GOES.  相似文献   
459.
Disaster risk management, particularly management of climate-related risks, has become central to the international policy agenda. Reducing hazard-related loss and damage relies heavily on scientific inputs. Science, in turn, relies on data—in this case 1) risk-related data on hazards, exposure and vulnerability, and 2) data on associated loss and damage outcomes. The latter, data on losses and damage, are also post-2015 international policy outcome indicators at the highest level, required for countries’ monitoring of progress in reducing disaster risk, adapting to climate change, and achieving sustainable development. Although the quantity and accessibility of loss and damage data are improving, a number of issues continue to constrain their potential. These include needs for more consistent cataloguing of hazards and extreme events, more systematic and accurate documentation of per-event losses and damage, more precise cross-referencing of hazard events with associated loss and damage, and improved standardization and interoperability among databases. We identify measures for improvement in this regard, both for research purposes and for post-2015 international policy implementation.  相似文献   
460.
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   
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