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931.
Inexact Fuzzy-Stochastic Programming for Water Resources Management Under Multiple Uncertainties 总被引:1,自引:0,他引:1
In this study, an interval-parameter fuzzy-stochastic two-stage programming (IFSTP) approach is developed for irrigation planning
within an agriculture system under multiple uncertainties. A concept of the distribution with fuzzy-interval probability (DFIP)
is defined to address multiple uncertainties expressed as integration of intervals, fuzzy sets, and probability distributions.
IFSTP integrates the interval programming, two-stage stochastic programming, and fuzzy-stochastic programming within a general
optimization framework. IFSTP incorporates the pre-regulated water resources management policies directly into its optimization
process to analyze various policy scenarios; each scenario has different economic penalty when the promised amounts are not
delivered. IFSTP is applied to an irrigation planning in a water resources management system. Solutions from IFSTP provide
desired water allocation patterns, which maximize both the system’s benefits and feasibility. The results indicate that reasonable
solutions are generated for objective function values and decision variables; thus, a number of decision alternatives can
be generated under different levels of stream flows. 相似文献
932.
Chaudhary P Singh SB Chaudhry S Nain L 《Environmental monitoring and assessment》2012,184(2):1145-1156
The present study is aimed at analysing and comparing different soil enzymes in soil samples of native contaminated sites
of a Mathura refinery and adjoining agricultural land. Enzyme activities are considered as indicators of soil quality and
changes in biogeochemical function due to management or perturbations. Soil samples were collected from the premises and nearby
area of Mathura refinery, India. Biological health parameters (dehydrogenase, aryl esterase, aryl sulphatase,
\upbeta \upbeta -glucosidase, alkaline phosphatase, acid phosphatase, lipase, laccase and catalase activity) were estimated in the soil samples.
Among all the samples, sewage sludge soil showed maximum activity of enzymes, microbial biomass carbon and most probable number
of polycyclic aromatic hydrocarbon (PAH) degraders in soils spiked with three- to four-ring PAHs at 50 ppm. Available phosphorus,
potassium and nitrogen was also exceptionally high in this sample, indicating maximum microbial bioconversion due to presence
of nutrients stimulating potent PAH-degrading microorganisms. 相似文献
933.
Karakaya and Sultansuyu Dam Lakes, located in the eastern part of Turkey, are important water sources, both for irrigation
and fishery. The main goal of the study was to investigate water qualities of dam lakes using a set of biomarkers in the fish
Cyprinus carpio. For this aim, field sample and laboratory-acclimated fish were compared to identify changes in selected biomarkers. The
activities of ethoxyresorufin-O-deethylase, glutathione S-transferase, glutathione reductase, and carboxylesterase were determined in liver samples. Also, plasma and liver lactate
dehydrogenase, aspartate aminotransferase, and alanine aminotransferase activities were assayed. Brain acetylcholinesterase
and carboxylesterase activities were also determined. The hepatosomatic index and condition factors were calculated. Plasma
vitellogenin assays were evaluated for the presence of xenoestrogen. Physicochemical values of water samples showed the existence
of eutrophication risk, and also, some chemicals in both lakes were determined to be over tolerable limits. The comparisons
of samples from both dam lake and laboratory-acclimated fish showed that the lakes may be at risk of pollution by some xenobiotics,
namely xenoestrogens and acetylcholinesterase-inhibiting agents. 相似文献
934.
The effect of two fly ashes as soil amendment on the adsorption–desorption of metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylphenyl)] and atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) was studied in alluvial and laterite soils. The adsorption data for both the herbicides fitted well the Freundlich equation, and Freundlich adsorption coefficient (K f) increased with an increase of fly ash amount. Both the fly ashes differed in their extent to increase herbicide sorption, and the effect was different in different soils. Atrazine was sorbed more in the soils/soils?+?fly ash mixtures than the metolachlor. The K f values showed significant correlation with the amount of fly ash amendment (correlation coefficient, R?>?0.982). The desorption isotherms also fitted the Freundlich equation, and desorption showed hysteresis which increased with an increase in the content of fly ash amendment. The free energy change (ΔG) indicated that the sorption process is exothermic, spontaneous, and physical in nature. The study has shown that fly ash as soil amendment significantly increased the sorption of metolachlor and atrazine, but the effect is soil- and fly ash-specific. 相似文献
935.
Effect of dust load on the leaf attributes of the tree species growing along the roadside 总被引:1,自引:0,他引:1
R. K. Chaturvedi Shikha Prasad Savita Rana S. M. Obaidullah Vijay Pandey Hema Singh 《Environmental monitoring and assessment》2013,185(1):383-391
Dust is considered as one of the most widespread air pollutants. The objective of the study was to analyse the effect of dust load (DL) on the leaf attributes of the four tree species planted along the roadside at a low pollution Banaras Hindu University (BHU) campus and a highly polluted industrial area (Chunar, Mirzapur) of India. The studied leaf attributes were: leaf area, specific leaf area (SLA), relative water content (RWC), leaf nitrogen content (LNC), leaf phosphorus content (LPC), chlorophyll content (Chl), maximum stomatal conductance (Gsmax), maximum photosynthetic rate (A max) and intrinsic water-use efficiency (WUEi). Results showed significant effect of sites and species for DL and the leaf attributes. Average DL across the four tree species was greater at Chunar, whereas, the average values of leaf attributes were greater at the BHU campus. Maximum DL was observed for Tectona grandis at Chunar site and minimum for Syzygium cumini at BHU campus. Across the two sites, maximum value of SLA, Chl and Gsmax were exhibited by S. cumini, whereas, the greatest value of RWC, LNC, LPC, A max and WUEi were observed in Anthocephalus cadamba. A. cadamba and S. cumini exhibited 28 and 27 times more dust accumulation, respectively, at the most polluted Chunar site as compared to the BHU campus. They also exhibited less reduction in A max due to dust deposition as compared to the other two species. Therefore, both these species may be promoted for plantation along the roadside of the sites having greater dust deposition. 相似文献
936.
Majid Soleimani Lope G. Tabil Ike Oguocha Jimmy Fung 《Journal of Polymers and the Environment》2018,26(2):532-542
The objective of this work was to improve the impact and thermal properties of polylactic acid (PLA)-based biocomposite by appropriate application of cellulosic fiber and a bioelastomer. Biocomposites formulations with fiber contents of up to 20% in combination with a bioelastomer were extrusion-compounded in a twin-screw extruder followed by molding in an injection molding system. Fibers used in the formulations included three types of cellulosic fiber; namely, raw fiber from oat hull biomass (RF), hydrolysis byproduct (ATF) which was the solid fraction obtained from an acid-catalyzed hydrolysis of RF, and delignified fibers (AD30, AD65, AD100) which were the products of delignification of ATF. Formulated biocomposites were characterized for thermal (glass transition and melting temperatures, and enthalpy of melting) and physico-mechanical (tensile and bending strengths, stiffness, impact energy, and water absorption) properties. Among all types of biofibers, RF resulted in poor properties in the biocomposites due to the high hemicellulose content in the structure. On the other hand, the ratio of lignin to cellulose (in the absence of hemicellulose) in the modified fibers did not significantly affect the physico-mechanical and thermal properties of the biocomposites. The elastomer applied in the formulations improved the impact energy, thermal properties, and elongation at break of the composites. However, it adversely affected the strength and water resistance of biocomposites, especially in the presence of hemicellulose. The results indicated that, depending on the application, a wide range of PLA green composites with different physico-mechanical properties can be achieved. 相似文献
937.
Shikha Raghuwanshi M. G. H. Zaidi Saurabh Kumar Reeta Goel 《Journal of Polymers and the Environment》2018,26(7):2661-2675
The global demand of bioplastics has lead to an exponential increase in their production commercially. Hence, biodegradable nature needs to be evaluated in various ecosystems viz. air, water, soil and other environmental conditions to avoid the polymeric waste accumulation in the nature. In this paper, we investigated the progressive response of two indigenously developed bacterial consortia, i.e., consortium-I (C-I: Pseudomonas sp. strain Rb10, Pseudomonas sp. strain Rb11 and Bacillus sp. strain Rb18), and consortium-II (C-II: Lysinibacillus sp. strain Rb1, Pseudomonas sp. strain Rb13 and Pseudomonas sp. strain Rb19), against biodegradation behavior of polyhydroxybutyrate (PHB) film composites, under natural soil ecosystem (in net house). The biodegraded films recovered after 6 and 9 months of incubation were analyzed through Fourier transform infrared spectroscopy and scanning electron microscopy to determine the variations in chemical and morphological parameters (before and after incubation). Noticeable changes in the bond intensity, surface morphology and conductivity were found when PHB composites were treated with C-II. These changes were drastic in case of blends in comparison to copolymer. The potential isolates not only survived, but, also, there was a significant increase in bacterial diversity during whole period of incubation. To the best of our knowledge, it is the first report which described the biodegradation potential of Lysinibacillus sp. as a part of C-II with Pseudomonas sp. against PHB film composites. 相似文献
938.
939.
Buse Tuğba Zaman Emine Gülhan Bakırdere Nursu Aylin Kasa Serenay Deniz Sabriye Sel Dotse Selali Chormey Sezgin Bakırdere 《Environmental monitoring and assessment》2018,190(7):437
This study describes the determination of trace levels of copper by slotted quartz tube atomic absorption spectrometry after dispersive liquid-liquid microextraction. A ligand synthesized from the reaction of salicylaldehyde and 1-naphthylamine was used to form coordinate copper complex prior to extraction. All parameters that influence the output of complex formation, extraction, and instrumental measurement were optimized to enhance the absorbance signal of copper. Under the optimum conditions, about 104-fold enhancement in sensitivity was recorded over the conventional flame atomic absorption spectrometer, corresponding to a 0.51 ng/mL detection limit. The percent relative standard deviation calculated for the lowest concentration (4.8%) indicated high precision for the experimental procedure. Accuracy and applicability of the optimum method were determined by performing spiked recovery tests on urine, lake water, and mineral water samples. Satisfactory recovery results were obtained between 82.2 and 106.3% at four different concentrations. Matrix matching method was also performed to increase the accuracy of quantification, and the percent recovery calculated for 175 ng/mL was 105.14%. 相似文献
940.
Oktay Yildiz Ernaz Altundağ Bilal Çetin Ş. Teoman Güner Murat Sarginci Bulent Toprak 《Environmental monitoring and assessment》2018,190(6):355
The afforestation of arid lands faces many challenges, and perhaps the most important key for success is choosing one or more species that are adapted well for local environmental conditions. We explored species that would be suitable for the steppe region of Central Anatolia. Intensive site preparation included ripping the subsoil (to 80 cm) and plowing the upper soil before planting seedlings of Elaeagnus angustifolia, Robinia pseudoacacia, Fraxinus angustifolia, and Pinus nigra were used as tree species. We also tested the success of several shrub species: Amygdalus orientalis, Calligonum polygonoides, and Spartium junceum. After five growing seasons, E. angustifolia showed the highest survival, with 80% of planted seedlings remaining. For the shrubs, A. orientalis was the most successful species with a 95% survival rate. Broad-leaved trees grew a cumulative average of 34 cm in height in 5 years, whereas P. nigra seedings grew only 9 cm. The greatest height growth occurred in the shrubs, with A. orientalis gaining 40 cm in height in 5 years. Overall, E. angustifolia and A. orientalis appeared best suited for afforestation in these areas. R. pseodoacacia and F. angustifolia may also be used as alternative species. 相似文献