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1.
Rashid Umar M. Muqtada A. Khan Izrar Ahmed Shakeel Ahmed 《Journal of Earth System Science》2008,117(1):69-78
The Kali-Hindon inter-stream region extends over an area of 395 km2 within the Ganga-Yamuna interfluve. It is a fertile tract for sugarcane cultivation. Groundwater is a primary resource for
irrigation and industrial purposes. In recent years, over-exploitation has resulted in an adverse impact on the groundwater
regime. In this study, an attempt has been made to calculate a water balance for the Kali-Hindon inter-stream region. Various
inflows and outflows to and from the aquifer have been calculated. The recharge due to rainfall and other recharge parameters
such as horizontal inflow, irrigation return flow and canal seepage were also evaluated. Groundwater withdrawals, evaporation
from the water table, discharge from the aquifer to rivers and horizontal subsurface outflows were also estimated. The results
show that total recharge into the system is 148.72 million cubic metres (Mcum), whereas the total discharge is 161.06 Mcum,
leaving a deficit balance of −12.34 Mcum. Similarly, the groundwater balance was evaluated for the successive four years.
The result shows that the groundwater balance is highly sensitive to variation in rainfall followed by draft through pumpage.
The depths to water level are shallow in the canal-irrigated northern part of the basin and deeper in the southern part. The
pre-monsoon and post-monsoon water levels range from 4.6 to 17.7 m below ground level (bgl) and from 3.5 to 16.5 m bgl respectively.
It is concluded that the groundwater may be pumped in the canal-irrigated northern part, while withdrawals may be restricted
to the southern portion of the basin, where intense abstraction has led to rapidly falling water table levels. 相似文献
2.
现代灌溉引水工程的发展,改善了灌区的农业用水条件,但同时改变了灌区上的自然生态环境、地质条件与水文地质条件等。分阶段总结了地下水的相关研究与应用;剖析了地下水调控的必要性与重要性;分析了地下水调控研究现状;最后通过总结给出了进一步研究的建议。 相似文献
3.
黄土台缘滑坡地表水入渗问题分析 总被引:7,自引:0,他引:7
黄土塬区提灌工程保证了农业生产,却造成了地下水位大幅抬升,使得近年来黄土台缘滑坡不断发生。黄土滑坡一个普遍特征就是后缘发育地裂缝以及落水洞,使地表水(灌溉水以及降雨)直接灌入坡体,诱发了大量黄土滑坡。因此,地表水入渗对于黄土滑坡机理研究以及滑坡防治具有重要意义。文章基于对陕西泾阳南塬黄土滑坡的现场调查,对黄土台缘滑坡地表水入渗工程地质问题进行了初步分析,包括:①地表水入渗与落水洞形成机制;②地表水入渗途径及其与黄土滑坡发育过程的关系;③降雨因素对于黄土滑坡的影响程度。 相似文献
4.
YousifK. Kharaka Evangelos G. Kakouros James J. Thordsen David L. Naftz 《中国地球化学学报》2006,25(B08):100-101
Selenium (Se) is an essential micronutrient to biota, but can become a potent toxicant at elevated concentrations. The natural sources and chemical properties of Se species make the boundary between deficiency and toxicity narrow for some biota, with both phenomena common around the globe. Large areas of farmland in the Colorado River Basin (CRB) generate salinized drainage water with Se concentrations much higher than 5 μg/L, the U.S. Environmental Protection Agency chronic water-quality criterion for the protection of aquatic life. We have carried out detailed field and laboratory studies to investigate Se geochemistry and remediation in two of these areas: the Middle Green River Basin, Utah and the Salton Sea Basin, California, located respectively in the Upper and Lower CRB. Results from these and other studies show that approximately 90% of the dissolved Se in the Colorado River and its tributaries originally is derived from the Upper Cretaceous Mancos Shale and equivalent pyritic marine units that outcrop in the Upper CRB. Selenium is mobilized commonly by biogeochemical oxidation of this pyritic shale and is concentrated mainly as selenate (SeO4^2-) in soils and agricultural drainage water of dry climates by evaporation. Minor (0%-5%) amounts of Se are present as the selenite species (HSeO3^-) and (SEO3^2-), but these species and the more reduced species, elemental Se (SeO) and selenide (Se^2-), have much lower solubility and/or have high sorptive affinity towards organic matter, clay minerals and iron oxyhydroxides. The concentration of dissolved Se (-2.5 μg/L) and salinity in the Lower Colorado River water are among the highest of the world major rivers. Because of low precipitation (7 cm/a) and extreme evapotranspiration (-1.8 m/a) rates in the Salton Sea Basin, California, Se values in irrigation water imported from the Colorado River increase to 〉300 μg/L in drainage wastewater. Removal of Se from contaminated wastewater by nanofiltration membranes was demonstrated in laboratory and pilot-scale field experiments. 相似文献
5.
华北平原东部淡水资源短缺,旱涝碱成灾害限制了农业生产的可持续发展。海河的治理,解决了排洪排涝排咸出路。春季开发利用地下水包括微咸水和半咸水抗旱灌溉。夏季利用伏雨洗盐排咸,增大降雨入渗,减少径流流失,防治渍涝灾害,把降雨转化为地下水资源。秋冬引蓄河水,回灌地下水补源。以土壤与潜水的地层空间作为调节大气降水、土壤水、地下水、地表水的地下水库,以调控地下水埋深在临界动态为指标,最大限度地把时空分布不均的天然降雨转化为可持续利用的水资源。地表水地下水联合运用,促使水资源采补平衡,降雨灌溉淋洗脱盐强于干旱蒸发积盐过程,地下水淡化强于矿化过程。实现旱涝碱咸综合治理,水土资源可持续利用,经济社会可持续发展,生态环境良性循环。 相似文献
6.
7.
利用土壤水分平衡方程,结合河南省冬小麦和夏玉米的生长规律和1994~2000年冬小麦、夏玉米田实测土壤湿度资料,建立了河南省冬小麦、夏玉米土壤水分预报及优化灌溉的计算机模型。用1998~1999年郑州市麦田实测土壤湿度资料验证该模型模拟结果,未来10、20、30天土壤湿度相对误差分别为-7.3%~7.7%、-8.3%~6.8%、-7.6%~7.7%,表明利用该模型,可以较为准确地预报未来1个月的土壤水分变化,并可根据小麦、玉米不同发育期特点,给出以最高产量和最佳经济效益为目标的灌溉建议。 相似文献
8.
An experiment on evapotranspiration from citrus trees under irrigation with saline waterwas carried out for 4 months. Two lysimeters planted with a citrus tree in the green house wereused. One lysimeter was irrigated with saline water (NaCl and CaCl2 of 2000 mg/L equivalence,EC = 3.8 dS/m, SAR = 5.9) and the other was irrigated with freshwater using drip irrigation. Theapplied irrigation water was 1.2 times that of the evapotranspiration on the previous day.Evapotranspiration was calculated as the change in lysimeter weight recorded every 30 minutes.The lysimeters were filled with soil with 95.8% sand. The results of the experiment were as follows.(i) The evapotranspiration from citrus tree was reduced after irrigation with saline water. Theevapotranspiration returns to normal after leaching. However it takes months to exhaust the saltfrom the tree. ( ii ) To estimate the impact of irrigation with saline water on the evapotranspirationfrom citrus trees, the reduction coefficient due to salt stress (Ks) was used in this experiment.Evapotranspiration under irrigation with saline water (ETs) can be calculated from evapotranspira-tion under irrigation with freshwater (ET) by the equation ETs = Ks× ET. Ks can be expressed as afunction of ECsw. (iii) The critical soil-water electrical conductivity (ECsw) is 9.5 dS/m, beyondwhich adverse effects on evapotranspiration begin to appear. If ECsw can be controlled at below9.5 dS/m, saline water can be safely used for irrigation. 相似文献
9.
《The Professional geographer》2003,55(2):285-287
Patrick McCully. New York: Blackwell Publishing, 2001. ill and 416 pp., diags., notes, apps., and index. $69.95 cloth (ISBN 1856499014), $25.00 paper (ISBN 1856499022). Reviewed by Patrick H. Buckley, Department of Environmental Studies, Policy, Planning, Education, and Geography, Western Washington University, Bellingham, WA. 相似文献
10.
This article explores the possibility of urbanization‐ and irrigation‐induced increases in summer precipitation totals in central Arizona. Maximum precipitation impacts are hypothesized to occur downwind of the Phoenix area in the Lower Verde basin. Results from statistical tests indicate that summer precipitation totals in the Lower Verde basin are greater than totals in nearby basins. Precipitation totals in the basin also appear to be equivalent to totals at more monsoon‐impacted stations in eastern Arizona. While this research is preliminary, the results do provide encouraging evidence of the existence of anthropogenically enhanced summer precipitation in central Arizona. 相似文献