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Modified DRASTIC assessment for intrinsic vulnerability mapping of karst aquifers: a case study 总被引：4，自引：1，他引：3
Groundwater in karstic aquifers can be dangerously sensitive to contamination. In this paper, DRASTIC assessment was modified
and applied, for the first time, to address the intrinsic vulnerability for karst aquifers. The theoretical weights of two
of DRASTIC’s parameters (aquifer media and hydraulic conductivity) were modified through sensitivity analysis. Two tests of
sensitivity analyses were carried out: the map removal and the single parameter sensitivity analyses. The modified assessment
was applied for the karst aquifers underlying Ramallah District (Palestine) as a case study. The aquifer vulnerability map
indicated that the case study area is under low, moderate and high vulnerability of groundwater to contamination. The vulnerability
index can assist in the implementation of groundwater management strategies to prevent degradation of groundwater quality.
The modified DRASTIC assessment has proven to be effective because it is relatively straightforward, use data that are commonly
available or estimated and produces an end product that is easily interpreted. 相似文献
2.
Evaluation of several techniques for estimating stormwater runoff in arid watersheds 总被引：2，自引：1，他引：1
Nidal Hadadin 《Environmental Earth Sciences》2013,69(5):1773-1782
Several traditional techniques have been used for estimating storm-water runoff from ungauged watersheds. Some of these techniques were applied to watersheds of Rashadia in south-eastern desert of Jordan. When engineers apply rainfall-runoff models for hydrologic design, there are difficulties in defining and quantifying peak discharges that are required to design different types of hydraulic structures. The lack of data presents major difficulties for rainfall-runoff modeling in arid regions. These regions have characteristically high rainfall intensity and consequent flash floods. The specific objectives of this study are: (1) apply synthetic hydrographs for estimating peak discharges from limited hydrological data. (2) Evaluate the reliability of six techniques to accurately estimate storm-water runoff; and, to evaluate the runoff that is required to design hydraulic structures such as bridges, culverts and dams. (3) Estimate the flood resulting from direct runoff after subtracting all the loses such as: the infiltration, interflow and evaporation. (4) Develop a simple regression relationship between peak flow discharges and catchment areas. The results show that there is uncertainty in determining the accuracy of storm-water volume, this is due to several methods were utilizing the estimation the hydrographs base time, but promising results in predicting the peak flow discharge. 相似文献
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We consider astronomical and geophysical bounds in order to test Kaluza-Klein like models and some particular models of Bekenstein's
theory. Bounds on the free parameteres of the theories are obtained.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Nidal Hadadin 《国际泥沙研究》2017,32(1)
The effects of basin hydrology on hydraulic geometry of channels variability for incised streams were investigated using available field data sets and models of watershed hydrology and channel hydraulics for the Yazoo River basin,USA.The study presents the hydraulic geometry relations of bankfull discharge,channel width,mean depth,cross-sectional area,longitudinal slope,unit stream power,and mean velocity at bankfull discharge as a function of drainage area using simple linear regression.The hydraulic geometry relations were developed for 61 streams,20 of them are classified as channel evolution model(CEM) Types Ⅳ and Ⅴ and 41 of them are CEM streams Types Ⅱ and Ⅲ.These relationships are invaluable to hydraulic and water resources engineers,hydrologists,and geomorphologists involved in stream restoration and protection.These relations can be used to assist in field identification of bankfull stage and stream dimension in un-gauged watersheds as well as estimation of the comparative stability of a stream channel.A set of hydraulic geometry relations are presented in this study,these empirical relations describe physical correlations for stable and incised channels.Cross-sectional area,which combines the effects of channel width and mean channel depth,was found to be highly responsive to changes in drainage area and bankfull discharge.Analyses of cross-sectional area,channel width,mean channel depth,and mean velocity in conjunction with changes in drainage area and bankfull discharge indicated that the channel width is much more responsive to changes in both drainage area and bankfull discharge than are mean channel depth or mean velocity. 相似文献
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