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141.
Agricultural irrigation accounts for nearly 70% of the total water use around the world. Uncertainties and climate change together exacerbate the complexity of optimal allocation of water resources for irrigation. An interval‐fuzzy two‐stage stochastic quadratic programming model is developed for determining the plans for water allocation for irrigation with maximum benefits. The model is shown to be applicable when inputs are expressed as discrete, fuzzy or random. In order to reflect the effect of marginal utility on benefit and cost, the model can also deal with nonlinearities in the objective function. Results from applying the model to a case study in the middle reaches of the Heihe River basin, China, show schemes for water allocation for irrigation of different crops in every month of the crop growth period under various flow levels are effective for achieving high economic benefits. Different climate change scenarios are used to analyze the impact of changing water requirement and water availability on irrigation water allocation. The proposed model can aid the decision maker in formulating desired irrigation water management policies in the wake of uncertainties and changing environment.  相似文献   
142.
Environmental Science and Pollution Research - Green macroalgae comprise significant amount of structural carbohydrates for their conversion to liquid biofuels. However, it generally relies on...  相似文献   
143.
Environmental Science and Pollution Research - Antibiotics are frequently used in the dairy sector for prophylactic uses along with therapeutic purposes. Throughout the globe, antibiotic resistance...  相似文献   
144.
Environmental Science and Pollution Research - Nano-titania (n-TiO2), due to its unique photocatalytic and hydrophobic properties, can be used to prepare self-cleaning cement-based smart building...  相似文献   
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147.

As a global pollutant, Hg (Hg) since the turn of the last century has received increased attention. Decreasing the emission of Hg into the food chain and the atmosphere is an effective way to reduce the Hg damage. The current study provided information about pilot-scale horizontal subsurface flow (HSSF) constructed wetlands (CWs) to remove different Hg species in polluted water. Synthetic wastewater was fed to two HSSF CWs, one was planted with Acorus calamus L and the other was unplanted as a control. The total Hg (THg), dissolved Hg (DHg), and particulate Hg (PHg) from five sites along the HSSF CWs were analyzed to describe the process of Hg removal. Results show that the CWs have high removal efficiency of Hg which is more than 90%. The removal efficiencies of THg and DHg from the unplanted CW were 92.1?±?3.6% and 72.4?±?13.1%, respectively. While, the removal efficiencies of THg and DHg in planted CW were 95.9?±?7.5% and 94.9?±?4.9%, which were higher than that in blank CW. The PHg was mainly removed in the first quarter of the CWs, which was also revealed by the partition coefficient Kd. To a certain extent, the effect of plants depends on the hydraulic retention time (HRT). The results in the current study show the potential of the HSSF-CWs for restoration from Hg-contaminated water.

  相似文献   
148.
A survey was conducted in Uttar Pradesh to enlist the available exotic fish species in culture. The culture and feeding details of unofficially introduced Clarias gariepinus was collected from 419 ponds existing in rural areas of 23 districts of Uttar Pradesh. The data indicated that 32% ponds were culturing exotic fishes of which 79% cases are of monoculture of exotic African catfish. Feeding analysis of these exotic African catfish revealed that 7% cases subsist on natural pond feed while 29% cases are fed on slaughter house waste. In 32% cases of the exotic magur monoculture, chicken waste was given whereas 11% cases were recorded with fish waste feeding. The possible threats and environmental risks of such unauthorised and indiscreminate culture of exotic magur has been discussed in this paper.  相似文献   
149.
Increasing soil pH retarded growth, tillers and bio-mass production of rice cultivar Sarjoo-52. Application of 10 to 15 kgZn ha(-1) increased the bio-mass by 33 to 41% at pH 8.5 and 27 to 32% at pH 10.3. Panicle length, rachis branches, total spikelets, filled grains, grain size were all adversely affected to the tune of 19, 23, 40, 74 and 21%, respectively by higher soil alkalinity at pH 10.3. Alkalinity resulted in 19, 31 and 65% spikelet sterility which reduced to 3, 21 and 55% at pH 8.5, 9.5 and 10.3, respectively by Zn applied @ 15 kg ha(-1). Grain yield reduced to 50% at pH 10.3 but Zn in general, raised the yield levels by 1.6 to 2.3, times. The chlorophyll decreased by 36 to 50% whereas carbonic anhydrase activities decreased only by 13% due to increase in soil sodicity and alkalinity. Further, increase in pH caused significant decrease in Zn, Ca, Mg, P and K concentrations but phenomenal rise in Na content Zinc application, apart from increasing tissue Zn content, elevated Ca :Na and K :Na ratio resulting in improved growth and yield of rice under soil sodicity and alkalinity.  相似文献   
150.
An attempt has been made to study antimicrobial resistance among the coliforms, faecal coliforms and faecal streptococci isolated from the runoff of the Gangotri glacier. The number of multiple antibiotic resistances (MAR) coliform isolates increases from upper stretch (33.33%) to lower stretch (83.33%). All faecal coliforms (100%) and faecal streptococci (100%) of lower stretch of study area showed multiple antibiotic resistances. Among coliforms, the value of Antibiotic resistance index (ARI) was found maximum in lower stretch (0.34) followed by middle stretch (0.29) and upper stretch (0.25).  相似文献   
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