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971.
MARIJKE WIJNROKS MARTIN W. BLOEM NAEL ISLAM HABIB RAHMAN SWAPAN KUMAR DAS ABDUL HYE GILLIAN HALL 《Disasters》1993,17(4):348-356
Early in 1992, Bangladesh experienced an influx of Burmese refugees, reaching a total of 263,000 by May. As the health and nutritional status of the refugee population was reportedly poor, a need was felt to collect dependable data through epidemiological surveillance, on which interventions could be based. The nutritional and health status of children was dramatically poor in all camps surveyed and a deterioration was expected in the coming monsoon. Several problem areas could be identified. Based on these findings it was possible to undertake appropriate action and to avert threatening calamities. Epidemiological surveillance is an important monitoring tool to provide reliable data on the health and nutritional status of refugee populations and to help the organizations involved to prioritize and evaluate their actions. 相似文献
972.
W. B. Kirchner S. Grabowski 《Journal of the American Water Resources Association》1972,8(6):1259-1264
This paper serves as a literature review of manganese in fresh water. The major aspects of manganese occurrence discussed are: (1) sources, (2) geochemistry, (3) manganese-iron relationships, (4) effects on the fauna and flora and (5) detection. 相似文献
973.
Charles W. Howe 《Journal of the American Water Resources Association》1971,7(4):670-675
ABSTRACT
Three main issues are discussed: the demands for additional water stemming from population dispersion; supply alternatives to large-scale interbasin transfers; and the displacement of agriculture from nonprofit regions. It is concluded that population dispersion is unlikely to increase aggregate water demands; that large additional supplies are available from other sources at lesser costs; and that a very likely consequence of large-scale transfers will be the displacement of agriculture in other parts of the country. 相似文献
Three main issues are discussed: the demands for additional water stemming from population dispersion; supply alternatives to large-scale interbasin transfers; and the displacement of agriculture from nonprofit regions. It is concluded that population dispersion is unlikely to increase aggregate water demands; that large additional supplies are available from other sources at lesser costs; and that a very likely consequence of large-scale transfers will be the displacement of agriculture in other parts of the country. 相似文献
974.
Dan M. Wells Ellis W. Huddleston Robert G. Rekers 《Journal of the American Water Resources Association》1971,7(1):124-132
ABSTRACT. .Eighteen rural lakes in Lubbock County were sampled on a routine basis following runoff-producing rainfall for a period of approximately eighteen months to determine whether or not runoff from intensively farmed agricultural areas contained significant concentrations of nitrates, phosphates, herbicides, or insecticides. An additional fifteen lakes lying within a triangle bounded by the cities of Plainview, Canyon, and Hereford, Texas, were sampled one time during the summer of 1969 to provide additional data regarding the nature and extent of the potential problem in an area with a different soil type and a slightly different cropping pattern. Based on results of detailed analyses of approximately two hundred samples of water collected from the lakes and an equal number of sediment samples collected from the same lakes at the same time, it appears that the concentrations of all chemical pollutants in runoff from agricultural lands in the High Plains are well below the allowable concentrations for drinking water. 相似文献
975.
Peter P. Zwack Mark D. Shulman John W. Philpot 《Journal of the American Water Resources Association》1969,5(4):9-15
A 30-year record of monthly precipitation for Northern New Jersey was analyzed for its statistical components. With a weak annual periodicity eliminated, the series was found to be random. The data for each month were fit with a gamma distribution using Thom's suggested best estimates of the distribution parameters. A one-thousand-year simulated monthly precipitation series was generated using random values from the twelve gamma distributions. The statistical properties of the simulated and sample time series agreed well. Numerous anomalous precipitation regimes were observed in the simulated data. 相似文献
976.
977.
W. Nentwig 《Die Naturwissenschaften》1999,86(9):411-421
Ecology is defined as the set of complex interactions between the biotic and abiotic environments. Human ecology concerns
principally the population ecology "only" of Homo sapiens, but it also includes all aspects of global ecology because humans are the most important species. Human demography is characterized
by a recent decline in mortality and fertility rates. These demographic transitions have largely been completed in industrialized
countries, but not in the 140 developing countries. Approximately 100 countries are following the same demographic pattern
as industrialized countries, however with a time delay of several generations. China has effectively reduced its population
increase by means that would be unacceptable in Western democracies. Some 44 developing countries still show increasing population
growth and no detectable demographic transition in birth rate. Thus one part of the world shows limited (and, in the long
run, shrinking) population growth, and another continues with a strong increase. All populations are limited in their development
by their sustainability by their environment, for example, food and energy resources, and the extent of pollution which the
use of these resources produces. It is argued that in the case of human population the limits of sustainability have already
been reached with the 6 billion humans alive today, since at least 20% of these suffer from hunger, natural resources are
overexploited, and biodiversity is threatened. In the coming 200 years it is more likely that the total population will substantially
oscillate rather than approach the predicted 12 billion. The most important goal of human ecology should therefore be to slow
population growth as far as possible. 相似文献
978.
Effect of manganese on the concentration of amino acids in different regions of the rat brain 总被引:5,自引:0,他引:5
Lipe GW Duhart H Newport GD Slikker W Ali SF 《Journal of environmental science and health. Part. B》1999,34(1):119-132
The present study was designed to determine if chronic exposure of weanlings and adult rats to Mn produces significant alterations in amino acid concentrations in different regions of the rat brain. Weanling (30 day old) and adult (90 day old) male rats were exposed to 10 and 20 mg Mn/kg body weight per day, by gavage, for 30 days. Forty-eight hours after the last dose, animals were sacrificed by decapitation and brains were dissected into different regions to determine the concentration of amino acids by HPLC/EC. A dose dependent decrease in body weight gain was found in the adult, but not in the weanling rats. Significant increases occurred in concentrations of aspartate, glutamate, glutamine, taurine and gamma-aminobutyric acid (GABA) in the cerebellum of the adult rats dosed with 20 mg/kg per day, Mn. A significant decrease in the concentration of glutamine was observed in caudate nucleus and hippocampus of weanling rats dosed with 10 mg/kg, Mn. These data suggest that chronic Mn exposure can produce a decrease in body weight gain in adult rats and alterations in amino acids in different regions of weanling and adult rat brains. 相似文献
979.
Aspects of the population dynamics ofMacrocystis integrifolia Bory were determined from harvested wild populations over a 26-month period and cultivated plants over a 40-month period. Mean wild plant size varied from 0.1 wet kg and two fronds in the winter to 3.1 wet kg and mine fronds in the summer. Plant recruitment probably occurred year-round with recruits making up 20 to 86% of the total population. Plant half-lives, estimated from population data, ranged from 1 to 3 months, with few plants exceedings 2 to 3 years in age. Standing crop ranged from 1.6 plants m-2 and 0.1 wet kg m-2 in winter to 8.3 plants m-2 and 8 wet kg m-2 in summer. 相似文献
980.
Lawrence W. Long 《环境质量管理》1992,2(2):193-196
Anheuser-Busch is a large, diversified corporation, both in its products and in its environmental efforts. It is well-known that Anheuser-Busch is the world'S largest brewer, with twelve operating breweries and a thirteenth under construction. It also operates the largest aluminum can recycling network in the world, Anheuser-Busch Recycling (A-BR). A-BR recycled more than 600 million pounds of aluminum in 1991, or more than 17 billion cans. This article describes how Anheuser-Busch has put TQEM ideas into practice involving all of its employees. 相似文献