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1.
Hussain  Zamir 《Natural Hazards》2017,86(1):107-123
Natural Hazards - The paper illustrates the results of regional flood frequency analysis of eleven sites of the four major rivers of Punjab, Pakistan. The discordancy measure (D i ) shows that none...  相似文献   

2.
Agricultural activities act as dominant polluter of groundwater due to increased fertilizers and pesticides usage. Bist-Doab region, Punjab, India, is one such region facing deterioration of groundwater quality due to usage of fertilizers. This study aims in delineating and evaluating the groundwater quality in the region. Water samples are collected from canals, reservoir, and shallow and deep groundwater. Water types in canal and reservoir in Kandi region are Mg2+HCO3 ? and Mg2+Ca2+Na+HCO3 ?, respectively. While water types of shallow and deep groundwaters are found to be of two types: Na+Mg2+Ca2+HCO3 ? and Ca2+Mg2+Na+HCO3 ?. Presence of Mg2+ in groundwater at locations adjoining canals indicates recharge due to canal. The major ion (Na+, Mg2+, Ca2+, HCO3 ?) chemistry of the region is due to weathering of rocks that are rich in sodic minerals and kankar. Deep groundwater quality in the region meets BIS and WHO standards for drinking purpose, unlike shallow groundwater which is of poor quality at many locations. Both shallow and deep groundwater with high sodium concentration (>1.5 meq/l) affect cropping yield and permeability of soil matrix. High concentration of SO4 2? and NO3 2? (>1 meq/l) in shallow groundwater at few locations indicates influence of anthropogenic (fertilizer) activity. Factor analysis indicates that the major cations, bicarbonate and chloride are derived from weathering/dissolution of source rocks. Higher concentration of nitrate and presence of sulphate in shallow groundwater at few locations is due to usage of fertilizers and pesticides.  相似文献   

3.
Salt tolerance in eighteen advanced rice genotypes was studied under an artificially salinized (EC=8.5 dSm?1) soil conditions after 90 days of transplanting. The results showed that the yield per plant, chlorophyll concentrations, fertility percentage, and number of productive tillers, panicle length and number of primary braches per panicle of all the genotypes were reduced by salinity. However, genotypes viz. Jhona-349 x Basmati-370, NR-1, DM-59418, DM-63275, DM-64198 and DM-38-88 showed better salinity tolerance than others.  相似文献   

4.
Groundwater is being used for drinking and irrigation purposes in the agricultural dominated Indian state of Punjab. Fifty-six groundwater samples were collected from Bathinda, a south-western district of Punjab, during the pre-monsoon (March 2010) and post-monsoon (October 2011) seasons. These samples were tested for major cations, anions and contaminants. Various classification systems were used to study the groundwater quality with respect to drinking as well as irrigation purposes. Total dissolved solids (TDS) and total hardness (TH) are generally used to determine the suitability of groundwater for drinking purpose. Considering TDS as a parameter, 54 and 57 % groundwater samples were found to be unsuitable for use during the pre- and post-monsoon seasons. A wide range of TH values were observed in the pre-monsoon and post-monsoon waters samples (mean 250 and 270 mgL?1). About 75 % of pre-monsoon and 79 % of post-monsoon samples exceeded the maximum permissible limit (MPL) of TH (150 mg L?1) proposed by WHO. In terms of contaminant ions, 40 % and 55 % of the pre- and post-monsoon water samples were unfit for drinking purposes w.r.t. fluoride (MPL 1.5 mg F L?1), 29 and 36 % were unfit w.r.t arsenic (MPL 10 μg L?1) and 33 and 45 % were unfit w.r.t nitrate (MPL 45 mg NO3 ? L?1), respectively. To determine the suitability of groundwater of Bathinda for irrigation purpose, three classification systems proposed by different research workers were used. The parameters electrical conductivity (EC), sodium adsorption ratio, and residual sodium carbonate (RSC) were calculated on the basis of chemical data. Considering EC and RSC together, 32 % samples collected during pre-monsoon season were fit, 19 % were marginal and 49 % were unfit for use. However, during post-monsoon, samples fit for irrigation decreased to 17 % and samples unfit for irrigation increased to 70 %. Increases in the percentage of unfit samples for irrigation after monsoon indicates addition of salts along with the rain water percolated into the groundwater. The other two classification systems, i.e. US Salinity diagram and Wilcox diagram also showed the similar results.  相似文献   

5.
A field experiment was carried out in order to investigate the effects of sewage sludge application on the growth and yield components of triticale (X Triticosecale Wittmack). Five treatments were compared: a control (C) without application of sludge or nitrogen fertilization; a mineral fertilization treatment (MF) applied as ammonium nitrate; and three sewage sludge treatments (SS), 6, 12, and 18 t ha?1, applied 15 days prior to triticale sowing. The main results showed that SS application improved plant growth by increasing leaf area index, tillering capacity, accumulated aboveground dry matter, and plant height of triticale. As a result, 18 t ha?1 of SS could be recommended the suitable dose for triticale, where dry matter production was more than twofold above the control value. No toxic effects arising from the heavy metals in triticale plants were observed. The Cu concentration was the only trace element that increased in the straw tissues with sludge application, although the values recorded were below critical environmental thresholds. Furthermore, growth and yield responses of triticale to all SS rates are comparable even sometimes more important than those for mineral fertilizer.  相似文献   

6.
The present study focuses on building a workflow for structural interpretation and velocity modeling and implementing to Jurassic-Cretaceous succession (Chiltan Limestone and Massive sand of the Lower Goru Formation). 2D-Migrated seismic sections of the area are used as data set and in order to confirm the presence of hydrocarbons in the study area, P and S-wave seismic velocities are estimated from single-component seismic data. Some specific issues in the use of seismic data for modeling and hydrocarbon evaluation need to deal with including distinguishing the reservoir and cap rocks, and the effects of faults, folds and presence of hydrocarbons on these rocks. This study has carried out the structural interpretation and modeling of the seismic data for the identification of traps. The results demonstrate existence of appropriate structural traps in the form of horst and grabens in the area. 2D and 3D velocity modeling of the horizons indicates the presence of high velocity zones in the eastern half of the study while relatively low velocity zones are encountered in the western half of the area. Two wells were drilled in the study area (i.e. Fateh-01 and Ichhri-01) and both are dry. Immature hydrocarbons migration is considered as a failure reason for Fateh-01 and Ichhri-01 well.  相似文献   

7.
The present research is contributed on groundwater quality, its deterioration and evaluation based on drinking, irrigation, and construction standards. The study area chosen for investigation on water quality is the Tirunagar (TN) area, located in the south-west of Madurai City. The TN area was formerly an agricultural land but presently a residential area that is at a starvation of drinking water quality. A total of 49 bore well samples from TN and Amaithisolai (AS) were investigated for drinking, irrigation, and construction qualities based on various physicochemical parameters. The chemistry of groundwater samples was reflected from very hard and noncarbonate-dominating species. TN was recorded with higher inorganic species in groundwater sources than AS. The Water Quality Index values indicated that 75 % of the samples fall under excellent category and the positive Langelier Saturation Index values of the samples highlighted their tendency to deposit calcium carbonate. The Gibbs plot showed that AS samples were categorized under the domination of rock–water interaction whereas the TN samples under evaporation zone. The US Salinity Laboratory Staff plot depicted that all the groundwater sources at AS with C3S1 type whereas 88 % of the TN sources represented C4S1 type. The results from Wilcox diagram for irrigation inferred that the groundwater sources at AS were permissible, but 68 % of the samples at TN was registered under unfit type. The suitability of groundwater from the knowledge of residual sodium carbonate, sodium absorption ratio, and sodium percentage was also investigated. The perception based on standards recommended the groundwater sources for construction activities. The contribution of ionic species and inter-relationship among the ions were also interpreted from the knowledge of statistical studies.  相似文献   

8.
变化环境下武江超定量洪水门限值响应规律及影响   总被引:2,自引:0,他引:2       下载免费PDF全文
世界众多江河洪水超定量(POT)系列门限值已发生变化,门限值选取不当会影响频率分析合理性.结合历史洪水资料,采用洪水POT理论分析变化环境下武江门限值响应规律及影响.结果表明:武江流域下垫面植被和径流系数在1991年明显改变,变化环境下不仅洪水门限值显著增大,且超过特定量级洪水的发生次数也在增加,POT模型能捕捉洪水在量级和发生次数方面的变化信息.分别选用变化环境前后门限值来推算设计洪峰,当重现期大于200年时,坪石站差异度达19.21%,犁市站达8.12%以上.选用变化环境后高门限值可有效提高线型对大洪水的拟合程度和设计洪水计算精度.  相似文献   

9.
变化环境下武江超定量洪水门限值响应规律及影响   总被引:1,自引:0,他引:1  
世界众多江河洪水超定量(POT)系列门限值已发生变化,门限值选取不当会影响频率分析合理性。结合历史洪水资料,采用洪水POT理论分析变化环境下武江门限值响应规律及影响。结果表明:武江流域下垫面植被和径流系数在1991年明显改变,变化环境下不仅洪水门限值显著增大,且超过特定量级洪水的发生次数也在增加,POT模型能捕捉洪水在量级和发生次数方面的变化信息。分别选用变化环境前后门限值来推算设计洪峰,当重现期大于200年时,坪石站差异度达19.21%,犁市站达8.12%以上。选用变化环境后高门限值可有效提高线型对大洪水的拟合程度和设计洪水计算精度。  相似文献   

10.
A new organic/inorganic composite based on polyacrylonitrile and stannic molybdophosphate (PAN–SMP) as an adsorbent was synthesized under various conditions. The physicochemical properties of this material were specified by elemental analysis, scanning electron microscopy, infrared spectroscopy and thermogravimetry studies. The synthesized material was found to be stable in demineralized water, in dilute acids, under gamma radiation up to the total radiated of 100 kGy doses and in high temperature up to 500 °C. Ion exchange capacity of the synthesized composite and its distribution coefficient (K d) for several metal ions were determined. The results showed that PAN–SMP has a great affinity toward some metal ions such as Tl+, Sr2+, Ba2+, UO2 2+ and La4+. Based on the determined K d values, two binary quantitative separations of metal ions (Cr6+ from Cu2+ and Pb2+ from Cu2+) have been achieved on columns of this ion exchanger. The ability of PAN–SMP to decontaminate low-level liquid waste was also investigated.  相似文献   

11.
Intensive agriculture by indiscriminate use of agrochemicals, sewage water, and polluted drain water has posed a serious threat to groundwater quality in some peri-urban areas of Delhi like Najafgarh block. The objective of the study was to determine the groundwater quality and to map their spatial variation in terms of suitability for irrigation and drinking purpose. Ordinary kriging method was used for preparation of thematic maps of groundwater quality parameters such as electrical conductivity, sodium adsorption ratio, bicarbonate, magnesium/calcium ratio, total dissolved solids, chloride, nitrate and hardness. Exponential semivariogram model was best fitted for all quality parameters except chloride and hardness, where spherical model fitted best. Pollution level was highest at south and south-eastern part of the study area. Better quality groundwater may be expected at the northern and western part. High salinity was due to high chloride concentration in the groundwater. Nitrate pollution level was found to be very alarming and need immediate interventions. High dissolved solids and hardness made the groundwater unsuitable for drinking. There were negligible sodium and bicarbonate hazard in the study area. The groundwater quality index was devised to analyse the combined impact of different quality parameters on irrigation and drinking purposes. The irrigation water quality index and drinking water quality index distribution maps delineated an area of 47.29 and 6.54 km2 suitable for irrigation and drinking, respectively. These safe zones were found as a small strip along the northern boundary and a very small pocket at the western side of the study area.  相似文献   

12.
张哲寰  刘凯  赵君  梁帅  魏明辉  刘洋 《物探与化探》2022,46(5):1087-1096
利用1:25万土地质量地球化学调查数据,根据《土地质量地球化学评价规范》和《土壤环境质量农用地土壤污染风险管控标准(试行)》,对逊克平原土壤质量和绿色产地土壤环境质量进行评价。结果显示: 逊克平原土地肥沃,环境优良,适合于发展绿色农业。①逊克平原土壤养分N、P、K、有机质、CaO、MgO、Fe2O3、S、B、Zn、Mn、Cu、Mo、Co、Ge、V 16项中,CaO、MgO、Cu、Zn为较缺乏,Ge、B缺乏,其他指标均为丰富和较丰富。土壤养分综合等级以丰富和较丰富为主,面积分别为6 088 km2和4 984 km2,分别占全区面积的44.58%和36.5%。②土壤环境质量综合等级以无风险为主,面积13 600 km2,占调查区面积的99.59%; 风险可控区面积56 km2,占0.41%。③土壤质量综合等级以优质土壤为主,面积为11 028 km2,占全区面积的80.76%; 良好土壤面积2 072 km2,占全区的15.17%; 中等土地面积556 km2,占4.07%,没有差等(四等)和劣等(五等)土壤。④逊克平原满足一级(AA级)绿色产地要求的土壤面积为13 396.45 km2,占全区面积的98.1%; 满足二级(A级)绿色产地要求的土壤面积为148 km2,占全区面积的1.1%; 不符合绿色食品产地要求的土壤面积为112 km2,占全区面积的0.8%。逊克平原土壤养分充足,环境清洁,开发绿色食品产地潜力巨大。  相似文献   

13.
14.
在农业生态地质调查基础上,通过对土壤有效态元素及石榴品质的测定,对影响河北省元氏县石榴品质的土壤物理化学因素进行了分析探讨。结果表明土壤母质岩性、母岩裂隙、土壤结构对石榴品质有一定的影响。在元氏丘陵山区片麻岩土、石英片麻岩土中P、K、Mg、Fe、Mn、Zn、B、S、Mo、Na、Mg、Cu、Si有效态元素含量高,母岩裂隙及土壤结构有利于水分及养分的保持和石榴根系吸收,有利于石榴的品质。  相似文献   

15.
The present study aims to discuss the hydrogeochemical processes in the Aosta Valley region and assess the quality of its groundwater for suitability of drinking and irrigation purposes. One hundred twenty-two samples were collected from the Aosta Valley region in the years 2007 and 2008 (61 per year), and analysed for pH, electrical conductivity, total dissolved solids (TDS), total hardness, major cations and anions. The pH of the samples in both years indicated a near-neutral to alkaline nature of the groundwater. The cation and anion chemistry showed the general ionic abundance as: Ca2+ > Mg2+ > Na+ > K+ and HCO3 ?>SO4 2?>Cl?>NO3 ?>F? in both years. Ca2+-Mg2+-HCO3 ? and Ca2+-Mg2+-Cl?-SO4 2? were the dominant hydrogeochemical facies. The computed saturation indices demonstrated that the groundwater was supersaturated with respect to dolomite and calcite in both years. The groundwater chemistry of the study area was mainly controlled by the dissolution of carbonate, sulphate and silicate minerals, as well as ion exchange processes. A comparison of the groundwater quality in relation to drinking water standards showed that most of the water samples were suitable for drinking and domestic uses. The computed water quality index (WQI) values of the study area groundwater ranged from 24 to 84 in the year 2007 and from 22 to 82 in the year 2008, and all the location fell under the Excellent to Good category. Quality assessment for irrigation uses revealed that the groundwater was good to permissible quality for irrigation; however, locally higher salinity, residual sodium carbonate (RSC) and magnesium hazard (MH) restricted its suitability for irrigation at a few sites. These results will be useful in implementing future measures in groundwater resource management at regional and national level.  相似文献   

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