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961.
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
962.
Lawrence J. MacDonnell David H. Getches William C. Hugenberg 《Journal of the American Water Resources Association》1995,31(5):825-836
ABSTRACT: The waters of the Colorado River are divided among seven states according to a complex ‘Law of the River’ drawn from interstate compacts, international treaties, statutes, and regulations. The Law of the River creates certain priorities among the states and the Republic of Mexico, and in the event of a severe sustained drought, the Law of the River dictates the distribution of water and operation of the elaborate reservoir system. Earlier work indicated that there is remarkable resilience in the system for established uses of water in the Lower Basin of the Colorado River. This work shows, based on an application of the Law of the River using computer modeling of operations of facilities on the Colorado River, that there may be serious environmental consequences and related legal restraints on how the water is used in times of shortage and that the existing legal and institutional framework governing the Colorado River does not adequately address all the issues that would be raised in a severe sustained drought. Several possible legal options for dealing with drought in the context of the Law of the River are identified. 相似文献
963.
Richard S. Krannich Sean P. Keenan Michael S. Walker Donald L. Hardesty 《Journal of the American Water Resources Association》1995,31(5):851-865
ABSTRACT: Survey data collected in the San Joaquin Valley of southern California and the Grand Valley of western Colorado reveal that residents of both areas believe that a severe sustained drought is likely to occur within the next 20–25 years and that their communities would be seriously impacted by such an event. Although a severe sustained drought affecting the Colorado River Basin would cause major economic and social disruptions in these and other communities, residents express little support for water management alternatives that would require significant shifts in economic development activities or in water use and allocation patterns. In particular, residents of these areas express little support for strategies such as construction and growth moratoriums, mandatory water conservation programs, water transfers from low-to high-population areas, water marketing, or reallocations of water from agricultural to municipal/industrial uses. This rejection of water management strategies that would require a departure from “business as usual” with respect to water use and allocations severely restricts the capacity of these and similar communities to respond effectively should a severe sustained drought occur. 相似文献
964.
Taiye B. Sangoyomi Benjamin L. Harding 《Journal of the American Water Resources Association》1995,31(5):925-938
ABSTRACT: We evaluated the effects of institutional responses developed for coping with a severe sustained drought (SSD) in the Colorado River Basin on selected system variables using a SSD inflow hydrology derived from the drought which occurred in the Colorado River basin from 1579–1616. Institutional responses considered are reverse equalization, salinity reduction, minimum flow requirements, and temporary suspension of the delivery obligation of the Colorado River Compact. Selected system variables (reservoir contents, streamflows, consumptive uses, salinity, and power generation) from scenarios incorporating the drought-coping responses were compared to those from Baseline conditions using the current operating criteria. The coping responses successfully mitigated some impacts of the SSD on consumptive uses in the Upper Basin with only slight impacts on consumptive uses in the Lower Basin, and successfully maintained specified minimum streamflows throughout the drought with no apparent effect on consumptive uses. The impacts of the coping responses on other system variables were not as clear cut. We also assessed the effects of the drought-coping responses to normal and wet hydrologic conditions to determine if they were overly conservative. The results show that the rules would have inconsequential effects on the system during normal and wet years. 相似文献
965.
本文概述了在制定和部署抗震救灾工作预案时,所引起地震误传事件的经过、对社会造成的影响,以及采取的对策和所汲取的教训。 相似文献
966.
Richard W. Paulson William G. Shope Jr. 《Journal of the American Water Resources Association》1984,20(4):611-618
ABSTRACT The use of satellite telemetry is playing a major role in the collection of hydrologic data. Advancing technology and availability of government satellites have permitted many agencies to take advantage of new procedures for acquiring data from automated remote data collection stations. Experiments with Earth satellite technology started in the 1960's and 1970's, with the polar-orbiting National Aeronautics and Space Administration Nimbus and Landsat satellites. Subsequent advancements took place through the development phase to operational systems using the Geostationary Operational Environmental Satellite (GOES) of the National Oceanic and Atmospheric Administration. This satellite system supports more than 2,500 active telemetry sites, of which approximately 1,200 are Geological Survey stream-gaging stations for the collection of hydrologic data. A satellite data collection system is made up of three primary components; a small battery-operated radio, and Earth-orbiting satellite, and an Earth receive and data processing station. The data relay satellites' vast aerial view of the Earth's surface gives satellite telemetry a large advantage over ground-based systems for the collection of real-time hydrologic data for flood warning, reservoir management, irrigation water control, hydropower generation, and the operation of hydrologic stations. 相似文献
967.
P. B. Martin 《Environmental management》1983,7(1):59-64
Two important habitat management strategies in pasture systems involve controlled burning and effective grazing manipulation schemes to maintain native climax grassland vegetation These climax grasslands have historically suffered less insect pest pressure than imported systems However, these types of grasslands are difficult to reestablish after relatively severe disruption by man Also, the proper diversity and stability is difficult to capture in developing imported systems. Imported pastures can exhibit substantial yields per land unit but are often composed of vegetation that rapidly mines nutrients stored by the native vegetation, and often need considerable inputs of fossil fuel, manufactured fertilizers and pesticides, because they are or become very susceptible to pestiferous insects. Habitat manipulation efforts can be effective in regulating forage pest populations below economic levels in imported pasture systems Such efforts include: 1) land use (coupled with plant diversity, grazing, and harvest manipulations), 2) sanitation (including controlled burning), 3) planting dates and harvest times (including grazing manipulations), 4) tillage methods, 5) fertilization, 6) trap crops, 7) water management, and 8) fire management for insect pest suppression and augmentation of natural enemies. 相似文献
968.
Recycling wastewater seems to have become a highly useful technique for meeting the shortage of fresh water in all parts of the world. It seems all the more important for Muslim countries because a large number of these countries face acute fresh water shortage. This paper views the problem from an Islamic viewpoint, that is, in the light of the Qur'n, theSunnah, andFiqh works.In Islamic law, water is classified into three categories oftahr,thir, andmutanajjis. The last two categories can be transmuted intotahr water and thus may be used for all mundane as well as religious purposes if they are assimilated into the overall supply oftahr water. This would be lawful from the Islamic viewpoint even without treating the water. To make use of modern technology in order to recycle wastewater effluents after treatment seems quite in keeping with the spirit and letter of the Islamic teachings. 相似文献
969.
青龙满族自治县被列为河北省桃林口水库上游重点治理区,境内大量“四荒”资源闲置浪费。该县立足县情,制定优惠政策,强化管理,因地制宜地开发这些资源,取得显著成效,其做法值得推广和借鉴。 相似文献
970.
By using fluidized-bed furnace and rotary-kiln+stoker furnace and four different kinds of industrial wastes such as waste wood, coffee mill, waste oils and waste plastics, we have drawn the following conclusions:
(1) A relationship between H6CBz and DXN is acquired, which is DXN=0.34×H6CBz1.1.
(2) The following means of emission reduction can be considered. (a) Reduction of DXN and Cl accumulation within the furnace, (b) control by the incinerated object, (c) control through the precursors of H6CBz, (d) improvement through operational control, (e) ammonia injection into the high-temperature zone of the furnace seems to be effective in reducing DXN and (f) DXN concentration is high with CO above 1800 ppm, though it decreases with CO below ≈10 ppm. 相似文献