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911.
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
912.
C. B. Cluff K. J. DeCook W. G. Matlock 《Journal of the American Water Resources Association》1971,7(4):726-739
ABSTRACT .Many growing municipalities near irrigated agriculture are advocating a transfer of water now utilized for irrigation to municipal use. Alternatives are presented whereby this water can be transferred to municipal use in exchange for treated sewage effluent. The irrigation water would in effect be cycled through the municipal system prior to use on the farms. A case study of the Tucson region illustrates the relevant legal, economic and technical aspects. Effluent could be delivered to irrigators in Avra Valley at a cost less than that now paid for water pumped from declining water tables. In return the City of Tucson could import ground water now being used for irrigation through an existing pipeline which presently cannot be used because of a court injunction obtained by the irrigators. It appears that such an exchange agreement could be made without modification of existing statutory law. Similar exchange arrangements may prove to be feasible in other regions containing irrigated agriculture. Increased efficiency of water use can be achieved avoiding external effects which commonly arise in a direct transfer and are difficult to evaluate. High quality water is allocated to municipal use whereas nutrient-rich sewage effluent is transferred to irrigation. 相似文献
913.
D. Goldberg B. Gornat M. Shmueli I. Ben-Asher M. Rinot 《Journal of the American Water Resources Association》1971,7(4):802-809
ABSTRACT .A study was conducted in two arid zones to determine the effect of saline water applied to various crops growing in coarse-textured soil, using trickle irrigation. The test crops responded most favorably to this new method of water application in terms of plant development and yield. The method provides us with the possibility of raising the permissible salinity level of irrigation water, and thus to increase the water reserves suitable for agricultural use in the world. 相似文献
914.
H. B. Osborn L. J. Lane R. S. Kagan 《Journal of the American Water Resources Association》1971,7(3):484-494
ABSTRACT Significant parameters for predicting thunderstorm runoff from small semiarid watersheds are determined using data from the Walnut Gulch watershed in southern Arizona. Based on these data, thunderstorm rainfall is dominant over watershed parameters for predicting runoff from multiple linear regression equations. In some cases antecedent moisture added significantly to the models. A technique is developed for estimating precision of predicted values from multiple linear regression equations. The technique involves matrix methods in estimating the variance of mean predicted values from a regression equation. The estimated variance of the mean predicted value is then used to estimate the variance of an individual predicted value. A computer program is developed to implement these matrix methods and to form confidence limits on predicted values based on both a normality assumption and the Chebyshev inequality. 相似文献
915.
Sa V. Ho B. Mason Hughes Philip H. Brodsky John S. Merz Larry P. Egley 《补救:环境净化治理成本、技术与工艺杂志》1999,9(3):103-116
Originated from a recognized need for significantly more effective technologies for soil cleanup, the LasagnaTM project provides an interesting case study in which industry, government, and academia successfully collaborated to rapidly advance the technology from the laboratory to the field. Called LasagnaTM because of its layered configurations, the technology combines electrically induced contaminant transport in soils, treatment in place, and geotechnical methods to achieve completely in situ clean-up of contaminated soils. Experiences with respect to the partnership, the development of technology and its current commercialization status are described. 相似文献
916.
The NGO, Action contre la Faim (ACF), has been operating in Burundi since 1994, where the situation has dramatically hampered humanitarian programmes. These include poor security resulting in an inability to maintain 24-hour care for the severely malnourished and poor access to the beneficiaries, all within a politically and economically unstable context. However, ACF has been able to capitalise on lessons learnt and reflect on ways to move forward, which have included the improvement of their capacities in the treatment of severe malnutrition and the integration within broader disciplines and national structures. The protocols for the treatment of severe malnutrition currently used in Burundi have been developed as a result of the research of ACF over the past five years. Other aspects of the nutrition programme remain to be further developed. These include, for example, an improved capacity to care for severely malnourished adolescents and adults; and also a better knowledge of the beneficiaries to allow for stronger links between the provision of treatment and support for their longer-term food security. 相似文献
917.
Identifying and mapping community vulnerability 总被引:30,自引:1,他引:29
Morrow BH 《Disasters》1999,23(1):1-18
Disaster vulnerability is socially constructed, i.e., it arises out of the social and economic circumstances of everyday living. Most often discussed from the perspective of developing nations, this article extends the argument using American demographic trends. Examples from recent disasters, Hurricane Andrew in particular, illustrate how certain categories of people, such as the poor, the elderly, women-headed households and recent residents, are at greater risk throughout the disaster response process. Knowledge of where these groups are concentrated within communities and the general nature of their circumstances is an important step towards effective emergency management. Emergency planners, policy-makers and responding organisations are encouraged to identify and locate high-risk sectors on Community Vulnerability Maps, integrating this information into GIS systems where feasible. Effective disaster management calls for aggressively involving these neighbourhoods and groups at all levels of planning and response, as well as mitigation efforts that address the root causes of vulnerability. 相似文献
918.
M. Brasseur-Daudruy C. Garel V. Brossard F. Broux B. Heckettsweiler D. Eurin 《黑龙江环境通报》2006,26(13):1254-1255
We suggest the term ‘hyper-echogenic colon’ to describe a hyperechoic foetal colonic content with no other intestinal abnormality. This is a rare pattern, which to our knowledge, has never been correlated with a specific pathology. The accidental observation of a cystine kidney stone in an infant who presented with this sign during the prenatal period made it possible to diagnose this disease retrospectively in two other children. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
919.
Among recent lemmings (D. torquatus from the Yamal Peninsula and D. groenlandicus from Somerset, Bathurst, Melville, and Devon islands), there are populations with archaic sets of morphotypes characteristic of the end of the Late Pleistocene. In some parts of the species range, lemming morphotypes follow the pattern characteristic of the Holocene stage of their evolution. Lemmings with the best developed tooth system live in the Bering Sea sector of the Arctic (Wrangel Island, Chukotka and Alaska). The correspondence of the boundaries of the groups distinguished by odontological traits to the phylogeographic data on mitochondrial DNA (mtDNA) and chromosomal groups is discussed. 相似文献
920.
Robert B. Olshansky 《Journal of Environmental Planning and Management》1996,39(3):371-386
Landslides continue to be an expensive problem in the U nited States. This paper explores the difficult problem of how to pay for reducing existing landslide risks. The paper examines a hierarchy of methods to cover repair and long term maintenance of unstable areas: assessment districts; homeowner associations; and insurance. It looks at several examples, and finds that costs in all but the worst cases average about $5000 to $15 000 per property. Landslide insurance is shown to be feasible and could be designed so as to encourage mitigation. The paper concludes that an optimal approach for mitigation and compensation would combine insurance with assessment districts. 相似文献