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131.
Shelter, housing and recovery: a comparison of u.s. Disasters   总被引:3,自引:0,他引:3  
Bolin R  Stanford L 《Disasters》1991,15(1):24-34
In this paper we examine the issues associated with the temporary sheltering and housing of victims after natural disasters in the United States. Specific topics addressed include differential access to shelter and housing aid according to social class, ethnicity and related demographic factors; the relationship between post-disaster shelter and housing and long-term recovery; the role of social support networks in the sheltering of victims; and the implications of the research for the provision of shelter and housing aid after disasters.  相似文献   
132.
Since 1983, concern has been expressed about the apparent decline in numbers of birds in the Ravenglass estuary in west Cumbria, particularly of the black-headed gull colony on the Drigg dunes, and suggestions have been made that this decline might be due to excessive radiation in the birds' food and their general environment. Twelve species of marine invertebrates from Ravenglass, most of them known to be important foods for birds, were analysed, and further samples were taken from sites along the west Cumbrian coast. None of these samples showed excessive contamination with any of the radionuclides analysed. Analysis of a sample of bird carcasses from the areas showed oystercatchers (Haematopus ostralegus) and shelduck (Tadorna tadorna) to have some of the highest concentrations of (137)Cs in their tissues; yet their breeding success and populations were not affected. Black-headed gulls, on the other hand, were found to be feeding mainly inland, and were the least contaminated with radionuclides of all the birds at Ravenglass, yet this species and its breeding success were in decline. Calculations of the total dose equivalent rate to the whole body of the most contaminated black-headed gull amounted to 9.8 x 10(-4) mSvh(-1) (approximately equal to 8.4 x 10(-4) mGy h(-1), whole body absorbed dose rate), and the background exposure dose was of the order of 8.3 x 10(-4) mGy h(-1). As a minimum chronic dose of 1000 mGy day(-1) has been found necessary to retard growth of nestling birds, and 9600 mGy over 20 days of incubation to cause the death of 50% of embryos in black-headed gulls' eggs, the concentrations of radionuclides in the foods, body tissues and general environment were at least three orders of magnitude too low to have had any effect. The more likely cause of the desertion of the gullery was the combination of an uncontrolled fox population, the severest outbreak of myxomatosis amongst the rabbits since 1954 and the driest May-July period on record, all in the same year (1984).  相似文献   
133.
Monitoring of airborne dust in Delhi during May to July 1985 revealed residues of DDT varying from 1.3 to 7.14 ng mg(-1) (4.06-22.31 ng m(-2) day(-1)) with an average of 3.32 ng mg(-1) (10.38 ng m(-2) day(-1)), and HCH which ranged from 0.46 to 2.35 ng mg(-1) (1.44-7.34 ng m(-2) day(-1)) with a mean of 1.16 ng mg(-1) (3.63 ng m(-2) day(-1)). The concentration of total DDT was almost 3 times greater than that of HCH.  相似文献   
134.
Spring wheat (Triticum aestivum L., cv. Drabant) was exposed to different concentrations of ozone in open-top chambers for two growing seasons, 1987 and 1988, at a site located in south-west Sweden. The chambers were placed in a field of commercially grown spring wheat. The treatments were charcoal-filtered air (CF), non-filtered air (NF) and non-filtered air plus extra ozone (NF(+)). In 1988, one additional ozone concentration (NF(++)) was used. Grain yield was affected by the ozone concentration of the air. Air filtration resulted in an increase in grain yield of about 7% in both years, compared to NF. The addition of ozone (NF(+), NF(++)) reduced grain yield and increased the content of crude protein of the grain in both years. Filtration of the air had no significant effect on the content of crude protein, compared to NF. The results showed a strong positive chamber effect on grain yield in the cold and wet summer of 1987. In 1988, there was no net chamber effect on grain yield. The relative differences between the CF, NF and NF(+) treatments with respect to grain yield were of the same magnitude in the two years, despite the very different weather conditions.  相似文献   
135.
Field-grown black cherry (Prunus serotina Ehrh.) seedlings were treated with the antioxidant ethylenediurea (EDU) to evaluate height, diameter, and above-ground dry-weight biomass growth response to ambient ozone over four years. Nine blocks with 44 trees/block were used in a randomized complete block design with three foliar spray treatments: (1) 1000 ppm EDU mixed with a surfactant and water; (2) surfactant mixed with water; and (3) water only. In each growing season treatments were applied seven times at approximately 10-day intervals. Repeated measures analysis of variance indicated significant (P< or =0.05) treatment and year effects for log-transformed height and diameter growth over the four-year period. After four years, EDU-treated trees were approximately 17% taller and stem diameters were 21% greater than non-EDU-treated trees. Total above-ground dry-weight biomass at the end of four years was 47% greater for EDU-treated trees compared to non-EDU-treated trees.  相似文献   
136.
Holland  N. D.  Leonard  A. B.  Meyer  D. L. 《Marine Biology》1991,111(1):113-119
The movement and digestion of food in the gut ofOligometra serripinna (Carpenter) were studied at Lizard Island (14°3842S; 145°2710E) in the austral winter of 1986. Feather stars in the laboratory were fed a brief, small meal of brine shrimp nauplii and killed at increasing time intervals thereafter. Histological reconstructions showed that the ingested nauplii progressed along the digestive tract surprisingly quickly. Some nauplii were found in the mid and hind intestine in only 30 min, and all of the nauplii had reached the hind intestine and rectum in 1 h. Digestion of the nauplii had started at 1 h, and only a few fragments of naupliar exoskeleton remained in the hind intestine and rectum 5 h after the start of feeding. Videotape analysis showed that no fecal pellets were released during this experiment. In the natural environment ofO. serripinna, ingested particles may similarly be transported quickly to the hind part of the gut and digested there — when feather stars were fixed in the field, most of the gut contents were found in the hind intestine and rectum.O. serripinna, which efficiently rejects inert particles before they are ingested, usually defecates infrequently (probably not more than once over a span of many hours) and differs from some other feather stars that ingest numerous inert particles and defecate much more frequently. When specimens ofO. serripinna were fed continuously on brine shrimp nauplii,Artemia sp. (San Francisco strain), in the laboratory, the feather stars fed gluttonously, packing their guts with several hundred nauplii in 1 to 2 h. Thereafter, superfluous feeding began (i.e., further ingestions appeared to force undigested nauplii, some of them still living, out of the anus). These observations suggest thatO. serripinna usually feeds at relatively modest rates in its natural habitat, but can feed gluttonously to take advantage of infrequent patches of highly concentrated, nutritious particles (e.g. copepod swarms, migrating demersal zooplankton, and invertebrate gametes from mass spawnings). It is likely that such patches of nutritious particles are usually small enough to drift out of reach of the feather stars before gluttonous feeding proceeds to superfluous feeding. Opportunities for superfluous feeding in nature are probably very infrequent (e.g. ingestion of coral gametes and embryos after a mass spawning), and the feather stars evidently have no behavior that stops further ingestions after the gut becomes filled to capacity.  相似文献   
137.
Stemwater running down the trunks of beech (Fagus sylvatica L.) has an acidifying effect on soil near the stem. The deposition of acidifying substances may be two to four times higher close to the stem compared to in the stand in general. To study reversibility of soil acidification, 72 stumps of beech trees were chosen from five different year classes of felling (3, 6, 9, 14-15, 25-30), representing the years when stemflow ceased to affect the soil. The H(+) concentration (pH KCl) in the topsoil (0-5 cm) differed between the distances 10-30 cm and 230-250 cm from the stumps, the soil close to the stem being more acid. The longer the time since felling the smaller the differences in H(+) concentration became. This reduction in soil acidity amounted to ca. 50% after 15 years, and only small further changes occurred over the next ten years. This indicates that soil may not recover fully from acidification, or does so at a rather slow rate after the initial 15 years of recovery.  相似文献   
138.
Effects of increased ozone (O3) and carbon dioxide (CO2) on polyamine levels were determined in soybean (Glycine max L. Merr. cv. Clark) grown in open-top field chambers. The chamber treatments consisted of three O3 regimes equal to charcoal filtered (CF), non-filtered (NF), and non-filtered plus 40 nl litre(-1) O3 and CO2 treatments equal to 350, 400 and 500 microl litre(-1) for a total of nine treatments. Leaf samples were taken at three different times during the growing season. Examination of growth and physiological characteristics, such as photosynthesis, stomatal resistance, and shoot weight, revealed that increasing CO2 ameliorated the deleterious effects of increased O3. Results from the initial harvest, at the pre-flowering growth stage (23 days of treatment), showed that increasing O3 at ambient CO2 caused increases in putrescine (Put) and spermidine (Spd) of up to six-fold. These effects were lessened with increased CO2. Elevated CO2 increased polyamines in plants treated with CF air, but had no effect in the presence of ambient or enhanced O3 levels. Leaves harvested during peak flowering (37 days of treatment) showed O3-induced increases in Put and Spd at ambient CO2 concentrations. However, increased CO2 levels inhibited this response by blocking the O3-induced polyamine increase. Leaves harvested during the pod fill stage (57 days of treatment) showed no significant O3 or CO2 effects on polyamine levels. Our results demonstrate that current ambient O3 levels induce the accumulation of Put and Spd early in the growing season and that further increases in O3 could result in even greater polyamine increases. These results are consistent with a possible antiozonant function for polyamines. The ability of increased CO2 to protect soybeans from O3 damage, however, does not appear to involve polyamine accumulation.  相似文献   
139.
The many abandoned base metal mines of the mid-Wales ore field are sources of extensive pollution. Some of the mineralised veins contain large amounts of pyrite and marcasite and oxidative weathering of these produces sulphuric acid resulting in very acidic mine drainage waters. In addition, the spoil tips associated with these mines can contain abundant iron sulphides. Drainage waters from these sources have pH values as low as 2.6 and are heavily contaminated with metals such as Al, Zn, Cd and Ni.Two of the main rivers of the area, the Rheidol and Ystwyth, intercept heavily contaminated acidic drainage which has a marked effect on water quality. The Rheidol contains over 100 g L–1 Zn for 16 km downstream of the acid water influx. This level is over three times the recommended EEC limit for Zn in salmonoid waters of low hardness.  相似文献   
140.
Lead and zinc effects on Bufo arenarum larval survival were studied in single and combined treatments. On a weight basis, lead is about twice as toxic as zinc. The antagonism or synergism between these heavy metals is dose-dependent.  相似文献   
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