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1.
ABSTRACT: Conflicts caused through development of urban areas in proximity to irrigated agriculture in water-scarce regions can be minimized through the direct urbanization of irrigated lands. This shifts the water supply from one use to another on the same site rather than creating an additional use in an adjoining area. This condition has prevailed in the Phoenix region. In the Tucson region, the municipality is buying and retiring farmland in an adjacent agricultural area, for the purpose of acquiring the water right in order to transfer water to municipal use. This land purchase is necessitated by existing Arizona water law, which ties the water to the land. This method of transfer creates problems concerning how much water can be transferred per acre retired; what to do with the abandoned farmland; inequities to agribusiness and taxing entities; and loss of food crop production which have not been resolved. An alternative to the retirement of farms, applicable in the Tucson region, is to exchange treated municipal wastewater for irrigation water. While this method appears to be the least disruptive, it requires the resolution of certain institutional problems concerned with land and water management method.  相似文献   

2.
ABSTRACT. The Bureau of Reclamation was created to implement the Reclamation Act of 1902 and subsequent legislation to conserve and develop the water resources of the western states for maximum efficient use. This has been accomplished by the planning and construction of major multiple use projects which now supply water to approximately eight million acres of land which annually produce 52 million tons of food and fiber with a gross crop value of approximately $2 billion. Fifteen million people are served with municipal and industrial water supplies and hydroelectric power from Bureau projects now returns $160 million annually to the Treasury. Flood control, recreation, and fish and wildlife enhancement are other major benefits. The Bureau of Reclamation is now undertaking a Westwide Survey of water resources and of the needs of the future which is more far-reaching than anything heretofore accomplished. The information accumulated during this ten-year survey will determine whether there is a necessity for consideration of major interbasin transfer of water supply.  相似文献   

3.
Food security concerns and the scarcity of new productive land have put productivity enhancement of degraded lands back on the political agenda. In such a context, salt‐affected lands are a valuable resource that cannot be neglected nor easily abandoned even with their lower crop yields, especially in areas where significant investments have already been made in irrigation and drainage infrastructure. A review of previous studies shows a very limited number of highly variable estimates of the costs of salt‐induced land degradation combined with methodological and contextual differences. Simple extrapolation suggests that the global annual cost of salt‐induced land degradation in irrigated areas could be US$ 27.3 billion because of lost crop production. We present selected case studies that highlight the potential for economic and environmental benefits of taking action to remediate salt‐affected lands. The findings indicate that it can be cost‐effective to invest in sustainable land management in countries confronting salt‐induced land degradation. Such investments in effective remediation of salt‐affected lands should form part of a broader strategy for food security and be defined in national action plans. This broader strategy is required to ensure the identification and effective removal of barriers to the adoption of sustainable land management, such as perverse subsidies. Whereas reversing salt‐induced land degradation would require several years, interim salinity management strategies could provide a pathway for effective remediation and further showcase the importance of reversing land degradation and the rewards of investing in sustainable land management.  相似文献   

4.
The Federal role in the enforcement of water quality requirements is of recent development. It began with the enactment in 1956 of the Federal Water Pollution Control Act as permanent law. It has been expanded by successive amendments to the Act to cover the pollution of navigable as well as interstate waters which endangers the health or welfare of persons, and to cover violations of water quality standards established for interstate waters. Two different enforcement procedures are prescribed in the law to be followed in the two types of enforcement actions. While questions have arisen of jurisdiction, States' rights, and disregard or duplication of local efforts, such questions do not lastingly impede the exercise of Federal enforcement authority and are of value in establishing a body of precedents. Limitations have their basis in the statutory distinctions between interstate and intrastate pollution which govern the application of the enforcement authority, even though a case of intrastate pollution may be as serious or more serious than a case of interstate pollution. An additional limitation results from the statutory time intervals between procedural stages in an action. Lack of data is a limitation but can always be overcome and at most causes delay. State laws which protect the confidentiality of required reports are more of a limitation. Investigative teams may obtain the needed information, however, for consideration in public meetings. Public support for effective water quality control measures, especially enforcement, and for the expenditures needed to enhance the environment, is widespread. Such support may be instrumental in modifying or eliminating existing statutory limitations.  相似文献   

5.
ABSTRACT: Completion of a 1270 acre recreational impoundment (Legend Lake) in the glacial sands of Menominee County, Wisconsin, produced geochemical and hydrologic alterations in some nearby natural lakes. The impoundment was produced by the construction of three dams, one of which proved to be temporary, connecting 9 natural lakes and ponds of 383 acres with 951 acres of flooded lands. Water levels were raised 3–15 feet within the impounded area. Much of the flooded area was peat rich wetland associated with the prior drainage. Water depths are less than 15 feet in 70% of the impoundment. Three seepage lakes, located less than 1/2 mile from the impoundment, experienced shoreline flooding, shoreline and soil erosion, some tree kills, and increased turbidity. These lakes also experienced concentration increases in several chemical constituents which indicate an influx of impoundment water through a regional alternation in the groundwater flow paths. The three lakes were connected by canals, and a 2.3 cfs gravity drain with an auxiliary pumping station was built to return excess water to the outflow of the impoundment. Future projects of this type would benefit from a more extensive hydrologic and geochemical analysis prior to initiation. Had environmental assessments been required at the time of this development, as they now are in Wisconsin for similar projects, some of the problems encountered might have been alleviated.  相似文献   

6.
ABSTRACT: Rapid population growth in the metropolitan area of Denver, Colorado, is causing conflicts over water use. Two cities, Thomton and Westminster, have begun condemnation proceedings against three irrigation companies to secure agricultural water rights for municipal use. This is the first condemnation proceeding against irrigation water rights for municipal use. Should the suit succeed, over 30,000 acres of presently irrigated land will lose its water supply. There are about four hundred landowners in the area; two hundred of these are commercial farmers, including truck, dairy and specialty farms. Total agricultural production amounts to about $8 million per year. About 561 jobs related to agriculture will disappear along with about $4 million in not income. Only 6.4 percent of the farmland along the Front Range is irrigated. Continued urban growth will put pressure on the water supply of much of this land. The interested parties of the region should cooperate to lessen the impact of urban growth on agricultural lands and water by forming a metropolitan water district. Such a district could share costs of development of additional municipal water and develop systems where municipalities would recycle waste water back to the irrigated lands.  相似文献   

7.
ABSTRACT: Economic models sometimes indicate that irrigation water is misallocated in agriculture, especially when it appears that the marginal value product is higher in other uses (such as for hydro-power). Historically, trends tend to contradict this reasoning, however, especially since irrigation has grown from 20 million acres in 1940 to over 50 million acres in 1980. Results of this study tend to indicate that as agriculture becomes more and more intensive (in terms of inputs), irrigation is part of that long term trend. Further, major economic variables, such as output and investments in agriculture, appear to be more highly correlated with irrigated land than with dryland agriculture. Recent data indicate an upper limit of about 320 million acres for dryland farming in the United States, while no such constraint is apparent for irrigated agriculture.  相似文献   

8.
ABSTRACT: Irrigation costs are rising rapidly on the 32 million acres irrigated with ground water. Ground water levels are declining under about 15 million of those acres adding to increased costs. However, from 1975 to 1982, 75 to 80 percent of increased ground water irrigation costs were due to higher nominal energy prices and interest rates. In real dollars, adjusted for inflation, these costs have risen faster than other irrigation costs and the real rise in commodity prices has been very small. A continuation of rapidly rising costs and slowly rising prices will shorten the economic life of those aquifers experiencing declining water levels. That same condition of prices and costs place all ground water irrigators in a disadvantaged position compared to nonirrigators and could cause a decline in ground water irrigation.  相似文献   

9.
Increasingly, the public and governmental agencies are concerned about remediating and reclaiming contaminated sites. Understanding the ecological resources on-site and valuing those resources in terms of future uses is important for determining suitable future land uses. In this article, we suggest the major categories of natural resource information required by managers, policy makers, and the general public for making initial future land-use determinations. We then use a dataset of 25 Department of Energy (DOE) sites slated for remediation to explore whether such data are readily available and whether the data can be used to assess natural resource value. Although information is available for almost all sites on federally endangered and threatened species, this information is less available for state-listed species. Biodiversity information is available only for some sites for birds (N = 17), mammals (N = 15), reptiles (N = 14), amphibians (N = 13), and plants (N = 11) and is almost nonexistent for invertebrates (N = 2). Some information is available for invasive species (N = 9). The number of available habitats is directly related to total acres and nonindustrial acres. Biodiversity of birds, mammals, and reptiles (but not amphibians) is directly related to both total acres and total nonindustrial acres of sites. These data suggest that even over a wide geographical area (from eastern to western United States), biodiversity relates to habitat size and number of habitats available. This information will be useful not only to DOE managers but also to natural resource trustees, ecologists, state and federal regulators, and the general public in the discourse over future uses of these lands.*Published online Author to whom correspondence should be addressed; Joanna Burger  相似文献   

10.
This study utilizes remote sensing derived forest aboveground biomass (AGB) estimates and ownership information obtained from the Protected Areas Database (PAD), combining landscape analyses and GIS techniques to demonstrate how different ownerships (public, regulated private, and other private) relate to the spatial distribution of AGB in New England states of the USA. “Regulated private” lands were dominated by lands in Maine covered by a Land Use Regulatory Commission. The AGB means between all pairs of the identified ownership categories were significantly different (P < 0.05). Mean AGB observed in public lands (156 Mg/ha) was 43% higher than that in regulated private lands (109 Mg/ha), or 30% higher than that of private lands as a whole. Seventy-seven percent of the regional forests (or about 9,300 km2) with AGB >200 Mg/ha were located outside the area designated in the PAD and concentrated in western MA, southern VT, southwestern NH, and northwestern CT. While relatively unfragmented and high-AGB forests (>200 Mg/ha) accounted for about 8% of total forested land, they were unevenly proportioned among the three major ownership groups across the region: 19.6% of the public land, 0.8% of the regulated private land, and 11.0% of the other private land. Mean disturbance rates (in absolute value) between 1992 and 2001 were 16, 66, and 19 percent, respectively, on public, regulated private, and other private land. This indicates that management practices from different ownerships have a strong impact on dynamic changes of landscape structures and AGB distributions. Our results may provide insight information for policy makers on issues regarding forest carbon management, conservation biology, and biodiversity studies at regional level.  相似文献   

11.
ABSTRACT: Legal, economic, and social constraints prevented the development of a surface outlet from an 878 acre watershed in the eastern Great Plains. However, frequent flooding of potentially excellent cropland within the watershed had to be controlled. The process of considering various alternatives within given constraints and utilizing natural features of the watershed to attain a water management system without surface runoff is presented. The coordinated system includes surface drainage, waterholding structures, and pumping plants. The excellent water control provided permits effective utilization of more than 115 acres of land which was previously of very low productivity.  相似文献   

12.
Drawing from experiences gained from the development and implementation of four approved habitat conservation plans (HCPs), I describe the goals and strategies used by the nine local government members of the Riverside County Habitat Conservation Agency (RCHCA) to reconcile conflicts among a rapidly growing population and the need to conserve the habitat of a number of declining wildlife species in western Riverside County, California. Several important goals have been pursued by RCHCA member governments in their sponsorship of multiple-species habitat conservation plans (MSHCPs), including (1) establishing certainty and control over future uses of land; (2) eliminating project-by-project negotiations with federal and state wildlife agencies; (3) coordinating mitigation obligations under the Endangered Species Act, Clean Water Act, California Environmental Quality Act, and other federal and state laws; (4) reducing conflict and litigation resulting from land development activities; and (5) ensuring that wildlife conservation activities are conducted in a manner that permits local governments to perform those functions necessary to maintain public health, safety, and welfare. I also describe the emergence of strategies by local governments to achieve MSHCP goals, including (1) use of an inclusive planning process that seeks to build consensus among affected interests; (2) extensive involvement of federal and state wildlife agencies in the preparation of MSHCP documents; (3) management of public lands to support MSHCP conservation objectives; (4) encouragement of voluntary conservation by private property owners through incentive programs; and (5) active solicitation of federal and state funding for MSHCP implementation activities.  相似文献   

13.
ABSTRACT: Agricultural lands (including most forest lands) make up almost four-fifths of the total land area of the United States and include, or are traversed by, perhaps an equal proportion of our ground and surface waters. Therefore, a very large part of our environment is directly “agriculture-related” in any consideration of the discharge of pollutants. Several important Federal and State laws relate to the control or abatement of agriculture-related pollution. Existing legislation generally mandates the control or abatement of pollution (from point or nonpoint sources) or authorizes the use use of public funds or other resources for such purposes. Some of these laws can be effective instruments in keeping pollutants from being discharged into surface or ground waters or into the air, but the degree to which some pollutants originating from agricultural lands and operations constitute a serious environmental hazard in waters remains controversial. Although most of the technology exists to reduce greatly the movement of these pollutants, investments are often required which benefit the nonfarm public without economic returns to the farmer. Whether a zero discharge is either an environmentally or economically feasible alternative to more limited or selective control, is explored. However, if the public is willing to bear its reasonable share of the cost for clean air and water, the needed basic legislation already largely exists. Under it, agricultural land holders may apply program standards and use their own and available program resources to bring about effective control or abatement of pollutants.  相似文献   

14.
Out study deals with the demand for water and alternative agricultural production and land use patterns under varying prices for both surface and ground water. We derive irrigation water demands for both the United States and regions of it. Not only is a different amount of water used at each set of water prices but also a different mix of crops, livestock, and production technology develops among the different regions. Under the highest set of prices used, more than fourteen million acres are converted into dryland farming. Total irrigated water use decreases by more than 25 million acre-feet. Irrigated crop yields are reduced and cropping patterns shift away from irrigation. Commodity shadow prices increase as much as 15 percent under high prices for both surface and ground water. A redistribution of farm income occurs between irrigated and dryland regions.  相似文献   

15.
This paper applies a property rights framework to federal mineral lands in the western United States from the enactment of the Mining Law in 1872 until the enactment of the Mineral Leasing Act for fossil fuels in 1920. There are two principal findings. First, the Mining Law appears to have been an effective means for assigning rights to mineral stocks on public lands (at least through 1920). This conclusion is supported by evidence from claim disputes in the West. Second, the impetus for the Mineral Leasing Act did not derive from the different physical characteristics of hardrock minerals and petroleum. The relevance of these conclusions to contemporary mineral policy is also discussed.  相似文献   

16.
ABSTRACT: The salinity of the lower South Platte River in Colorado is characterized by plotting the average annual flow, total dissolved solids, and salt mass flow against distance along the stream. The plots show that salts are being leached from the irrigated lands above Greeley and are being deposited on the irrigated lands below Greeley. The salt deposition on the lower lands will result in their salination. The plots show also that fall and winter stream flows carry most of the salt loads. These fall and winter flows are stored in off stream reservoirs for use during the irrigation season. Therefore these salts are transferred to the lower irrigated lands where they accumulate. The salt balance for these lands can be improved by permitting the fall and winter flows to leave the basin, or by providing adequate land drainage coupled with supplemental irrigation water.  相似文献   

17.
Wetlands provide a variety of ecological services, but are attractive sites for many development activities. Between the mid-1950's and mid-1970's about 550,000 acres, or about 0.5 percent, of the vegetated wetlands remaining in the conterminous states were converted to other uses each year. About 80 percent of these losses involved draining and clearing of inland wetlands for agricultural purposes. Recent reductions in national wetland conversion rates are due primarily to declining rates of agricultural drainage and secondarily to government programs that regulate wetlands use. Several governmental policies and programs exist that either encourage or discourage wetland conversions. Section 404 of the Clean Water Act is the major tool for Federal involvement in controlling the conversion of wetlands to other uses. The 404 program, in combination with State regulatory programs, is responsible for reducing annual conversions nationwide by about 50 percent of what is applied for, or 50,000 acres of wetlands per year, primarily through project modifications. Coastal wetlands are reasonably well protected. Inland, freshwater wetlands are generally poorly protected. Efforts to protect wetlands, given a set level of resources, could be improved by categorizing wetlands according to their relative importance and focusing existing wetland programs on high value wetlands.  相似文献   

18.
US Federal law mandates that mined land be returned by mine operators to a condition capable of supporting its pre-mining use or a higher use. Previously forested lands have commonly been reclaimed to hayland/pasture or wildlife habitat, and most of these lands have been abandoned from management and rendered non-productive. This situation has left landowners in the position of converting these reclaimed mined lands to forests at a later date, if they choose to make them economically productive. Such land-use conversion, however, comes with a substantial up-front cost to the landowner, which makes the financial viability of such a conversion questionable. We examine the financial viability of reforestation of these previously reclaimed mine lands by calculating land expectation value (LEV) under a range of conditions that include forest type, site quality, and reforestation intensity. We find that conversion to white pine is viable on higher quality sites under low to moderate interest rates with low or high timber prices, but conversion to mixed hardwoods is only profitable under the high price scenario with low interest rates, and only on higher quality sites. We also consider the implications of a shift in reforestation burden from the landowner to the mine operator, and results suggest that including costs of reforestation as part of the mining operation creates a financially viable forest enterprise for landowners under all scenarios for both white pine and mixed hardwoods. Two forms of carbon payments that could encourage reforestation of previously reclaimed mined lands also are examined: an annual payment based upon the total accumulated carbon found on-site in a given year, and an annual payment based on only the increment of carbon storage each year. Our carbon payment results indicate that annual values of up to $5.17 per ton of carbon stored in hardwoods and $9.39 per ton of carbon stored in pines would be required to make reforestation profitable under the poorest conditions (high interest rates, low prices, and poor quality site) when the payment is based on accumulated on-site carbon, although lower values are required under more favorable scenarios. Payments that are based upon the annual increment of carbon must fall in the range of $8.66–$71.88 per ton of carbon stored in hardwoods and $0–$83.29 per ton of carbon stored in pines to make reforestation financially viable.  相似文献   

19.
China’s new Classification-Based Forest Management (CFM) is a two-class system, including Commodity Forest (CoF) and Ecological Welfare Forest (EWF) lands, so named according to differences in their distinct functions and services. The purposes of CFM are to improve forestry economic systems, strengthen resource management in a market economy, ease the conflicts between wood demands and public welfare, and meet the diversified needs for forest services in China. The formative process of China’s CFM has involved a series of trials and revisions. China’s central government accelerated the reform of CFM in the year 2000 and completed the final version in 2003. CFM was implemented at the provincial level with the aid of subsidies from the central government. About a quarter of the forestland in China was approved as National EWF lands by the State Forestry Administration in 2006 and 2007. Logging is prohibited on National EWF lands, and their landowners or managers receive subsidies of about 70 RMB (US$10) per hectare from the central government. CFM represents a new forestry strategy in China and its implementation inevitably faces challenges in promoting the understanding of forest ecological services, generalizing nationwide criteria for identifying EWF and CoF lands, setting up forest-specific compensation mechanisms for ecological benefits, enhancing the knowledge of administrators and the general public about CFM, and sustaining EWF lands under China’s current forestland tenure system. CFM does, however, offer a viable pathway toward sustainable forest management in China.  相似文献   

20.
A hedonic price function is estimated that illustrates how the price per acre of open space paid by public buyers such as counties or land trusts, is influenced by local demand and supply factors. The empirical regression model is illustrated using 133 public transactions (73% are purchases and 27% are easements) of open space in the Front Range of Colorado. The mean price per acre was $13 635. If a property provides access to water bodies, this feature increases the price per acre by $937, while adjacency of the parcel to existing park or open space adds $11 039 an acre. A 1% increase in county population results in a 0.27% increase in price per acre. Easements cost $6783 less than purchases, a sizeable cost saving. The prediction capability of the hedonic price equation may be an alternative to traditional real estate appraisal techniques when agencies must determine fair market values of prospective open space parcels that vary in attributes from existing ones.  相似文献   

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