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71.
20 0 1 0 1 2 6印度西北部的普杰地区发生了 7 8级强烈地震。对这次强震事件 ,利用卫星遥感监测地气系统射出长波辐射的数值产品资料 ,分析了以普杰为中心整个西亚范围内 ,事件发生前后共计 6个月的月平均辐射场的分布特征及其演变过程。发现自震前 2个月至震时当月 ,普杰地区始终是一个辐射 (热 )场的高值中心 ,震后明显消散。据此认为印度大地震有可识别的预警信息 ,提出利用卫星遥感技术及其产品 ,有可能为“突破”短临地震预报开拓出一种新的预测技术生长点 相似文献
72.
George Mulamoottil Robert Farvolden 《Journal of the American Water Resources Association》1975,11(3):599-604
ABSTRACT: By field investigations and planning, it is profitable to rehabilitate gravel pits as recreational lakes in urban areas. Some of the important aspects to be considered are topography, soil, surface water and groundwater. A case study is presented and some general guidelines in the rehabilitation process are given. This kind of a use for derelict land is important at the present time as there is a growing demand for recreational lakes in urban areas. 相似文献
73.
Thomas J. Jackson Richard H. McCuen 《Journal of the American Water Resources Association》1979,15(2):436-446
ABSTRACT: Remote sensing offers an attractive alternative to conventional data collection employed in the estimation of certain hydrologic model parameters. In this investigation, the standard error of parameters estimated from Landsat data are examined. Relationships between the standard error and the size of the spatial-modeling units are developed that allow extending results to larger areas. Based upon the investigations conducted, a generalized model of the error relationships could not be developed. 相似文献
74.
Judith A. Pickering Richard A. Andrews 《Journal of the American Water Resources Association》1979,15(4):1039-1049
ABSTRACT: The objective of the study was to evaluate alternative land developments around New Hampshire lakes. Alternative development patterns, evaluated by their impacts on the lake area environment and area economy, included residential patterns, commercial patterns, and combinations of these two types. Phosphorus loading of the lake water was used as a proxy variable for changes in the lake water quality. Commercial developments yielded the highest revenues to the town and the local area. It also attracted the most lake users to the area as well as contributing the largest phosphorus loading in the lake waters. Residential developments, although contributing high revenues to the businessmen in the area, yielded less net income to the town. Phosphorus loading levels from residential developments were much lower than lake phosphorus loading by commercial developments. 相似文献
75.
S. F. Shih 《Journal of the American Water Resources Association》1980,16(4):724-727
ABSTRACT: The water budget computation in shallow lakes is complicated because marsh vegetation can transpire large quantities of lake water. Thus, a model including the marsh zone evapotranspiration (WET) was developed to compute the water budget for Lake Okeechobee. Three periods of testing (1969–74), planning (1963–74), and recorded period (1952–77) were used to compare the differences of the sum of storage deviation between the WET and conventional methods (WOET). Results of the WOET method showed that the sum of stage deviations were 87.42 cm (2.868 ft.), 231.80 cm (7.605 ft.), and 284.50 cm (9.333 ft.) in the testing, planning, and recorded periods, respectively. These stage deviations are equivalent in the same order to 29, 76, and 93 percent of the lake volume. In general, the WET method not only was applicable to compute the water budget for the lake but also reduced the sum of storage deviation by about 42, 31, and 49 percent, respectively, in those three periods. The storage deviation in WET method was reduced on an average to about 2 percent each year in all three periods, and the deviations were scattered more randomly than in WOET. 相似文献
76.
J. Roger McHenry Jerry C. Ritchie Frank R. Schiebe 《Journal of the American Water Resources Association》1977,13(1):81-92
ABSTRACT: The total suspended sediment loads of four north Mississippi reservoirs were determined from measurements of concentrations of suspended sediment in a vertical profile at several locations on each reservoir made during the year. These data were combined with the stage-height and known stage-volume relationships for each reservoir in a numerical integration to determine the total suspended sediment in the water body. Total suspended sediments were estimated using the product of the suspended sediment concentration in the surface water by the appropriate reservoir volume. The averaged ratios of the estimated to measured suspended sediment loads for each reservoir exceeded 0.90. Since the concentration of suspended sediments in surface waters of north Mississippi reservoirs has been shown as highly correlated with spectral reflectance, estimating the total suspended sediment of these reservoirs using remotely sensed spectral reflectance data is possible. 相似文献
77.
Albert Rango Arthur T. Anderson 《Journal of the American Water Resources Association》1974,10(5):1060-1081
ABSTRACT. The Spring 1973 Mississippi River flood was investigated using remotely sensed data from ERTS-1. Both manual and automatic analyses of the data indicate that ERTS-I is extremely useful as a regional tool for flood management. Quantitative estimates of area flooded were made in St. Charles County, Missouri and Arkansas. Flood hazard mapping was conducted in three study areas along the Mississippi River using pre-flood ERTS-1 imagery enlarged to 1:250,000 and 1:100,000 scale. The flood prone areas delineated on these maps correspond to areas that would be inundated by significant flooding (approximately the 100 year flood). The flood prone area boundaries were generally in agreement with flood hazard maps produced by the U. S. Army Corps of Engineers and U. S. Geological Survey although the latter are somewhat more detailed because of their larger scale. Initial results indicate that ERTS-1 digital mapping of flood prone areas can be performed at 1:62,500 which is comparable to some conventional flood hazard map scales. 相似文献
78.
ABSTRACT: To investigate the magnitude of denitrification and assimilatory nitrate reduction as these reactions relate to the fate of nitrate reaching sediments via groundwater seepage, undisturbed core samples of sediments (40 cm length) from two lakes (Mendota and Tomahawk) were leached from the bottom (at 1.4 cm/day) with a solution of 15N-nitrate (10 mg N/liter). The sediment columns were fitted with Pt electrodes to measure the oxidation-reduction (Eh) potential. While leaching removed considerable ammonium-N and soluble organic N, essentially no 15N had passed through the columns by 50 days. The Eh readings indicated that denitrification was occurring in the lower portions of the columns. The 15N distribution of the sediment N after 50 days showed that about 15 to 26% of the added nitrate-N was converted to organic N and ammonium-N. The data show that denitrification can be a significant N sink in seepage lakes. 相似文献
79.
80.
Gail Krantzberg 《The Environmentalist》2008,28(3):301-305
Some argue that a collective vision for the future of the Laurentian Great Lakes is embodied in the␣Great Lakes Water Quality
Agreement (GLWQA). The GLWQA is a binational agreement, first signed in 1972 by Prime Minister Pierre Trudeau and President
Richard Nixon, wherein the two countries (the Parties) commit to “restore and maintain the chemical, physical and biological
integrity of the waters of the Great Lakes Basin Ecosystem.” Article X of the Agreement states that the Parties shall conduct
a comprehensive review of the operation and effectiveness of this Agreement following every third biennial report of the [International
Joint] Commission (IJC). The IJC’s 12th Biennial Report, released in 2004, triggered this important science, program, and
policy review which commenced May 2006. This essay makes the case for a rigorous review, that explores deliberately the future
scope of the Agreement to protect the world’s largest surface freshwater resource, and calls for innovation in the governance
regime of this binational ecosystem. 相似文献