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Design and Implementation of Aquaculture Pond Water Quality Assessment System Based on Fuzzy Mathematics 被引量:2
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作者 王瑞梅 傅泽田 何有缘 《Agricultural Science & Technology》 CAS 2010年第7期171-175,共5页
The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond water quality,the system of index estimation and assessment standard were established afte... The aquaculture pond water quality was taken as research objects,based on the general analysis of factors influencing the pond water quality,the system of index estimation and assessment standard were established after sorting by importance of the factors by means of Delphi and expert investigation.In this study,index weight was confirmed according to the importance of the factors and relative membership grade of the measured values,thus and the fuzzy comprehensive evaluation model of aquaculture pond water quality was constructed,and the fuzzy comprehensive evaluation system of freshwater aquaculture pond water quality was designed and implemented.The application of this system in the assessment of aquaculture pond water quality by a company had achieved better result. 展开更多
关键词 pond AQUACULTURE water quality Fuzzy comprehensive evaluation
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Application of Fuzzy Comprehensive Evaluation Method Based on Entropy Weight to Evaluate Pond Water Quality 被引量:1
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作者 吴会民 张韦 +4 位作者 梁传辉 樊振中 谢刚 高勇 缴建华 《Agricultural Science & Technology》 CAS 2012年第3期664-668,共5页
[Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Meth... [Objective] This study was to provide references for the evaluation of water quality in aquaculture ponds by evaluating the pond water quality using fuzzy comprehensive evaluation method based on entropy weight. [Method] The fuzzy compre- hensive evaluation method based on entropy weight was used to evaluate the water quality in the ponds with Ukraine scale carp (Cyprinus carpio) as the main cultivated fish. The average size of the fish was 71.4 g/ind, and totally three groups of pond were set with the population density of 6 000, 9 000, 12 000 ind/hm2. [Result] According to the GB3838-2002 Environmental Quality Standards for Surface Water of China, the water quality of 6 000 ind/hm2 group was Grade I, and the water quality of 9 000 and 12 000 ind/hm2 were Grade V. [Conclusion] With the increasing of feeding density, the pond water quality would worsen, however, there is no difference on water quality between 9 000 and 12 000 ind/hm2 groups. 展开更多
关键词 water quality Aquaculture pond Fuzzy comprehensive evaluation method Entropy weight
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Influence of pore water pressure on upper bound analysis of collapse shape for square tunnel in Hoek-Brown media 被引量:5
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作者 黄阜 张道兵 +1 位作者 孙志彬 吴贲 《Journal of Central South University》 SCIE EI CAS 2011年第2期530-535,共6页
To investigate the effective shape of collapsing block in square tunnel subjected to pore water pressure,the analytical solution of detaching curve was derived using upper bound theorem of limit analysis with Hoek-Bro... To investigate the effective shape of collapsing block in square tunnel subjected to pore water pressure,the analytical solution of detaching curve was derived using upper bound theorem of limit analysis with Hoek-Brown failure criterion. The work rate of pore water pressure,which was regarded as an external rate of work,was taken into account in the framework of limit analysis. Taking advantages of variational calculation,the objective function with respect to detaching curve was optimized to obtain the effective shape of collapsing block for square tunnel. According to the numerical results,it is found that the varying pore water pressure coefficient only affects the height and width of the collapsing block,whereas the shape of collapsing block remains unchanged. 展开更多
关键词 upper hound theorem square tunnel pore water pressure variational calculation Hoek-Brown media
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Seasonal and Interannual Variations of Upper Tropospheric Water Vapor Band Brightness Temperature over the Global Monsoon Regions 被引量:2
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作者 钱维宏 朱亚芬 +1 位作者 谢安 叶谦 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1998年第3期55-63,共9页
The upper-troposphere water vapor (UTWV) band brightness temperature (BT) dataset derived from the High-resolution Infrared Radiation Sounder (HIRS) channel 12 of the National Oceanic and Atmospheric Administration (N... The upper-troposphere water vapor (UTWV) band brightness temperature (BT) dataset derived from the High-resolution Infrared Radiation Sounder (HIRS) channel 12 of the National Oceanic and Atmospheric Administration (NOAA) polar satellites from 1979 to 1995 is used to analyze the seasonal and interannual variations for the global monsoon regions. Results show that (i) there are three major regions where the UTWV band BT varies significantly with season, i.e., South Asia, the western coastal South-North America tropical region and the low-latitude African region; (ii) UTWV band BT clearly reveals the water vapor temporal/spatial features as well as the atmospheric circulation structure over the low-latitude during the monsoon onset; and (iii) there is a remarkable relationship between the interannual variation of the UTWV band BT over the monsoon regions and the sea surface temperature anomaly in the eastern equatorial Pacific. 展开更多
关键词 MONSOON Seasonal variation Interannual variability upper tropospheric water vapor Brightness temperature
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Water quality in forest and village ponds in Burkina Faso(western Africa) 被引量:1
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作者 Bilass Zongo Frdric Zongo +1 位作者 Aboubacar Toguyeni Joseph I.Boussim 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第5期1039-1048,共10页
Forest ecosystems help conserve the quality of water resources in aquatic habitats. The conservation of biological diversity in aquatic and terrestrial ecosystems remains a communal concern. Aquatic ecosystems and res... Forest ecosystems help conserve the quality of water resources in aquatic habitats. The conservation of biological diversity in aquatic and terrestrial ecosystems remains a communal concern. Aquatic ecosystems and resources are vulnerable but can be preserved and protected by forests. In sub-Saharan regions of Africa, water from ecosystems such as ponds still play important role in the livelihood of local populations. Water from temporary ponds is used by local populations for multiple needs; however, in this part of the world, the population is increasing, thus increasing human needs and activities and land use in the region. Land-use changes lead to deforestation, land degradation and the decline in freshwater, affecting human health and well-being. Forest degradation leads to the decline in ecosystem goods and services, particularly those related to watersheds. This study conducted in eastern Burkina Faso aimed to assess water quality of temporary ponds in protected forest areas (reserves) and surrounding villages. It was conducted in 61 temporary ponds where physical, chemical and biological variables were measured, such as water surface area, depth, transparency, macrophyte cover, pH, dissolved O<sub>2</sub>, conductivity, nutrient concentrations and algae biomass. The results showed that at p < 5%, water surface area (p = 0.02), depth (p = 0.00), nutrient content (p = 0.00), and algae biomass (p = 0.04) were significantly higher outside reserves than inside reserves. In contrast, macrophyte cover (mean cover percentages 53 vs. 44.5%) and water transparency (p = 0.02) were higher inside reserves. The variations in conductivity and pH were not significant. All trends showed the influences of human activities on water characteristics and the role forests and land cover had in preventing negative human impacts and disturbance of temporary ponds. Forests and land cover are important to water quality conservation and algae biomass regulation in temporary ponds. Protecting and managing forests is therefore an essential part of future strategies for limiting algal blooms and their negative consequences, maintaining water quality and providing clean water to citizens. 展开更多
关键词 Ecosystem services pond water RESERVES VARIABLES Western Africa
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Assessment of Climate Change Impact on Water Resources in the Upper Senegal Basin (West Africa) 被引量:3
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作者 Mamadou Lamine Mbaye Stefan Hagemann +3 位作者 Andreas Haensler Tobias Stacke Amadou Thierno Gaye Abel Afouda 《American Journal of Climate Change》 2015年第1期77-93,共17页
This study assesses the potential impacts of climate change on water resources and the effect of statistical bias correction on the projected climate change signal in hydrological variables over the Upper Senegal Basi... This study assesses the potential impacts of climate change on water resources and the effect of statistical bias correction on the projected climate change signal in hydrological variables over the Upper Senegal Basin (West Africa). Original and bias corrected climate data from the regional climate model REMO were used as input for the Max Planck Institute for Meteorology-Hydrology Model (MPI-HM) to simulate river discharge, runoff, soil moisture and evapotranspiration. The results during the historical period (1971-2000) show that using the bias corrected input yields a better representation of the mean river flow regimes and the 10th and 90th percentiles of river flow at the outlet of the Upper Senegal Basin (USB). The Nash-Sutcliffe efficiency coefficient is 0.92 using the bias corrected input, which demonstrates the ability of the model in simulating river flow. The percent bias of 3.88% indicates a slight overestimation of the river flow by the model using the corrected input. The evaluation demonstrates the ability of the bias correction and its necessity for the simulation of historical river regimes. As for the potential changes of hydrological variables by the end of 21st century (2071-2100), a general decrease of river discharge, runoff, actual evapotranspiration, soil moisture is found under two Representative Concentration Pathways (RCP4.5 and RCP8.5) in all simulations. The decrease is higher under RCP8.5 with uncorrected data in the northern basin. However, there are some localized increases in some parts of the basin (e.g. Guinean Highlands). The projected climate change signal of these above variables has the same spatial pattern and tendency for the uncorrected and bias corrected data although the magnitude of the corrected signal is somewhat lower than that uncorrected. Furthermore, the available water resources are projected to substantially decrease by more than -50% in the majority of the basin (especially in driest and hottest northern basin with RCP8.5 scenario) for all data, except the Guinean highlands where no change is projected. The comparison of simulations driven with uncorrected and bias corrected input reveals that the bias correction does not substantially change the signal of future changes of hydrological variables for both scenarios over the USB even though there are differences in magnitude and deviations in some parts of the basin. 展开更多
关键词 Climate Change Impact Signal BIAS Correction upper Senegal BASIN water RESOURCES
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Retrieval of Upper Tropospheric Relative Humidity by the GMS-5 Water Vapor Channel:A Study of the Technique 被引量:1
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作者 黄毅 王美华 毛节泰 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第1期53-60,共8页
This paper presents an analysis of a technique for retrieving upper tropospheric relative humidity through the GMS-5 satellite's 6.7-micron water vapor channel brightness temperature. NCEP analysis shows that a cr... This paper presents an analysis of a technique for retrieving upper tropospheric relative humidity through the GMS-5 satellite's 6.7-micron water vapor channel brightness temperature. NCEP analysis shows that a critical assumption of the retrieval theory, namely the constant temperature lapse rate, matches only in the tropical atmosphere. By statistical analyses of brightness temperature simulated by a radiative transfer model and of relative humidity, we examine the effect of lapse rate on this retrieval method and obtain retrieval parameters and error estimates applicable to the GMS-5 satellite over East Asia. If the retrieval parameters are properly chosen, the relative error of retrieving the upper tropospheric relative humidity in this region is less than 10%, and if applied to the low-latitude summer atmosphere, it is less than 5%. 展开更多
关键词 upper troposphere water vapor satellite retrieval brightness temperature
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Biological Effects of Nutrient Nualgi on the Water Ecological Environment in Culture Pond 被引量:1
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作者 Li Gu Mao Mengzhe +2 位作者 Li Xiaoli Tao Ling Gao Maolin 《Animal Husbandry and Feed Science》 CAS 2016年第6期369-376,共8页
In order to study the short-term effects of Nualgi on water quality and phytoplankton in fishpend, we conducted continuous and regular surveys on the phytoplankton community and the water quality indexes in four group... In order to study the short-term effects of Nualgi on water quality and phytoplankton in fishpend, we conducted continuous and regular surveys on the phytoplankton community and the water quality indexes in four groups. The four groups were a Nualgi group ( M1 ), a diatom group ( M2 ), a Nualgi and diatom group (M3), and a control group (C). The results showed that there were no significance differences in pH, dissolved oxygen (DO), total nitrogen (TN) and total phosphorus (TP) among the four groups. The IP concentration of groups MI and M3 was significantly lower than that of groups M2 and C, indicating that Nualgl can reduce the IP concentration of water. The concentrations of NH4+ -N, NO2- -N and CODMn, of groups M1 , M2 and M3 were sigeificantly lower than those of group C, suggesting that both Nualgi and dominant diatom species can adjust water quality by reducing the concentrations of NH4+ -N, NO2- -N and CODMR. In this test, we identified 186 species that belonged to 109 genera of seven phyla. Among them, 86 species were Chlorophyta, 48 were Bacillariophyta, 27 were Cyanophyta, 17 were Euglenophyta, three were Dinophyta, three were Cryptophyta and two were Chrysophyta. Both diatom species and Nualgi can promote the growth of Bacillariophyta, restrain the growth of Chlorophyta and Cyanophyta, and thus change phytoplankton community structure. The biomass of Bacillariophyta in groups M1, M2 and M3 was larger than that in group C from the 20th d of the experiment, while the biomasses of Chlorophyta and Cyanophyta were lower than that in group C. Melo- sira granulata became the dominant algae species in groups M1, M2 and M3 , while Coelastrum microporum and Crucigenia tetrapedia were the dominant algae species in group Conly. Scenedesmus quadr/cauda became the dominant algae in groups M1 , M2 and C. There was no remarkable difference in diversity index among the four groups. The Shannon-Wiener index in all the four groups were all above 2.00, suggesting that the addition of Nualgi or diatom species did not affect the species diversity in this experiment. 展开更多
关键词 Nualgi DIATOM PHYTOPLANKTON pond water quality
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Review on Pond Aquaculture Tail Water Treatment Technologies 被引量:2
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作者 Shunlong MENG Lihua REN +6 位作者 Xi CHEN Liping QIU Chao SONG Limin FAN Dandan LI Jiazhang CHEN Pao XU 《Agricultural Biotechnology》 CAS 2022年第2期93-98,共6页
Carrying out the treatment of aquaculture tail water and realizing the discharge and recycling of the aquaculture tail water are the inevitable trend in the development of the fishery industry at present and in the fu... Carrying out the treatment of aquaculture tail water and realizing the discharge and recycling of the aquaculture tail water are the inevitable trend in the development of the fishery industry at present and in the future.For this reason,this paper reviewed the characteristics of pond aquaculture tail water,the sources of pollutants in intensive aquaculture tail water,the important parameters in the water body that affect the growth of cultured organisms,and the water treatment methods in the process of aquaculture,and prospected from the technical level and industrial policy level,hoping to accumulate data for promoting the green development of aquaculture and cleaner production. 展开更多
关键词 pond aquaculture Tail water treatment POLLUTANT PARAMETER
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Water quality characteristics of rivers and ponds in Japan 被引量:1
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作者 高橋幸彦 杜茂安 中村玄正 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第5期501-505,共5页
In Japan, various countermeasures have been taken to improve the water quality of public waters such as rivers and lakes. Though water quality has improved, it is still insufficient. In summer, eutrophication is seen ... In Japan, various countermeasures have been taken to improve the water quality of public waters such as rivers and lakes. Though water quality has improved, it is still insufficient. In summer, eutrophication is seen in lakes and inner bays, as well as rivers. As a countermeasure to prevent eutrophication, the removal treatment of nutrient salts such as nitrogen and phosphorus is done, in addition to organic substance elimination in the domestic sewerage system. This report will show the water quality characteristics of rivers and ponds in Japan. It is considered that these investigative results are effective when the water quality improvement of the stabilization ponds where eutrophication occurs are examined in China. 展开更多
关键词 water quality characteristics EUTROPHICATION nitrogen and phosphorus stabilization ponds
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Cr (Ⅲ) Removal from Synthetic Waste Water by Using Water Pond Mud 被引量:1
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作者 Ashok Kumar Balwant Singh Bisht +2 位作者 Amitabh Talwar Manish Kumar Lalit Kumar 《Journal of Life Sciences》 2010年第3期33-35,共3页
The pollution of aquatic ecosystem by heavy metals has assumed serious proportions due to their toxicity and accumulative behavior. The toxicity metal is dependent on its chemical form and therefore removal of metal i... The pollution of aquatic ecosystem by heavy metals has assumed serious proportions due to their toxicity and accumulative behavior. The toxicity metal is dependent on its chemical form and therefore removal of metal is more meaningful than the estimation of its concentrations. In this study, the batch experiments were carried out under 30℃ to study the effect of pH, initial Cr concentration, adsorbent dose and contact time on the removal of Cr (lII). The maximum adsorption efficiency (99%) was observed when 1.5 g of pond mud was used for removal ofCr (Ⅲ) from test solution containing 150 mg·Cr / 100 ml. The optimal pH and contact time recorded during the study were 6 and 10.0, respectively. 展开更多
关键词 Aquatic ecosystem TOXICITY water pond mud contact time adsorption.
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Application of polymeric flocculant for enhancing settling of the pond ash particles and water drainage from hydraulically stowed pond ash 被引量:1
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作者 Mishra Devi Prasad Das Samir Kumar 《International Journal of Mining Science and Technology》 SCIE EI 2013年第1期21-26,共6页
Delayed settling of the ash particles and poor drainage of water from the pond ash are the major problems faced during the hydraulic stowing of pond ash. In this study the effect of polymeric flocculant on settling of... Delayed settling of the ash particles and poor drainage of water from the pond ash are the major problems faced during the hydraulic stowing of pond ash. In this study the effect of polymeric flocculant on settling of the ash particles and drainage of water during pond ash stowing are investigated. In addition, the parameters, viz. drainage and absorption of water during pond ash stowing are quantified by stowing a mine goaf model with pond ash slurries of five different concentrations added with and without flocculant. The study revealed that addition of only 5 10 6 of Sodium Carboxymethyl Cellulose (Na-CMC) flocculant with the pond ash slurries during stowing offers best result in terms of quicker settling of the ash particles and enhanced water drainage from the hydraulically stowed pond ash. Besides, it resulted in drainage of more than 85% of the total water used in the initial 45 min of stowing. The improvement in drainage is caused due to coagulation and flocculation of the pond ash particles because of charge neutralization and particle-particle bridging. This study may provide a basis for estimating the drainage and absorption of water during the real pond ash stowing operation in underground mines. 展开更多
关键词 Fly ash pond ash Stowing Settling water drainage Polymeric flocculant
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Water masses classification of the upper layer in the Equatorial Western Pacific using ISODATA of fuzzy cluster 被引量:1
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《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第2期187-201,共15页
-In this paper,by using ISODATA of fuzzy cluster,the water masses classification of the upper layer in the E-quatorial Western Pacific is carried out. On the basis of the degree of the membership in the obtained optim... -In this paper,by using ISODATA of fuzzy cluster,the water masses classification of the upper layer in the E-quatorial Western Pacific is carried out. On the basis of the degree of the membership in the obtained optima) classification matrix, the solid distribution of the detailed structure of water masses is made. The water of the upper layer,consisting of six water masses,may be divided into three layers,i, e. ,the surface,subsurface and intermediate layer. Besides analyzing the features of various water masses,a discussion on their distribution structure and formation mechanism is also made. 展开更多
关键词 water masses classification of the upper layer in the Equatorial Western Pacific using ISODATA of fuzzy cluster ISODATA
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Annual Variation of Water Quality in Aquaculture Ponds for Apostichopus japonicus 被引量:1
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作者 Yaoming LUO Yuan CHENG +4 位作者 Duohui LI Zhiying GAO Luping WANG Jiangyi WU Dawei JIANG 《Asian Agricultural Research》 2019年第11期25-27,共3页
By measuring water temperature,salinity,pH,dissolved oxygen,nitrite and ammonia nitrogen,the annual variation regularity of water quality in the aquaculture ponds for sea cucumbers Apostichopus japonicus in Dalian wer... By measuring water temperature,salinity,pH,dissolved oxygen,nitrite and ammonia nitrogen,the annual variation regularity of water quality in the aquaculture ponds for sea cucumbers Apostichopus japonicus in Dalian were studied.Results showed that the physicochemical indicators kept changing in the year,and the various ranges of water temperature,salinity,pH,dissolved oxygen,nitrite,and ammonia nitrogen were 6.38-27.27℃,29.20‰-33.78‰,7.86-8.38,5.19-13.36 mg/L,0.0037-0.0090 mg/L and 0.0171-0.0908 mg/L,respectively.Analysis indicated that there was an extremely significant negative correlation between water temperature and dissolved oxygen(P<0.01),an extremely significant positive correlation between water temperature and ammonia nitrogen(P<0.01),a significant negative correlation between salinity and nitrite(P<0.05),a significant negative correlation between dissolved oxygen and nitrite(P<0.05),and an extremely significant negative correlation between dissolved oxygen and ammonia nitrogen(P<0.01)in the aquaculture ponds for sea cucumber in Dalian.Research showed that the water quality of aquaculture ponds kept fluctuating all the time during the tested period,there were complicated and close relationships among physicochemical indicators,and a slight variation of external factors would bring consecutive reactions to different indicators in the water quality of aquaculture ponds.A reference for the production and management of sea cucumbers could be provided from the results. 展开更多
关键词 AQUACULTURE pondS for Apostichopus JAPONICUS water quality PHYSICOCHEMICAL indicator
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Models to predict sunlight-induced photodegradation rates of contaminants in wastewater stabilisation ponds and clarifiers
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作者 Xi-Zhi Niu 《Water Science and Engineering》 EI CAS CSCD 2019年第4期293-297,共5页
Two kinetic models were established for conservative estimates of photodegradation rates of contaminants under sunlight irradiation,in particular for wastewater stabilisation ponds and clarifiers in conventional waste... Two kinetic models were established for conservative estimates of photodegradation rates of contaminants under sunlight irradiation,in particular for wastewater stabilisation ponds and clarifiers in conventional wastewater treatment plants.These two models were designated for(1)contaminants with high photolytic rates or high photolytic quantum yields,whose photodegradation is unlikely to be enhanced by aquatic photosensitisers;and(2)contaminants withstanding direct photolysis in sunlit waters but subjected to indirect photolysis.The effortlessly intelligible prediction procedure involves sampling and analysis of real water samples,simulated solar experiments in the laboratory,and transfer of the laboratory results to realise water treatment using the prediction models.Although similar models have been widely used for laboratory studies,this paper provides a preliminary example of translating laboratory results to the photochemical fate of contaminants in real waters. 展开更多
关键词 Sunlight irradiation PHOTODEGRADATION CONTAMINANTS Stabilisation ponds Solar water treatment
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Contamination of Pond Water and Sediment in Coal Burning Area
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作者 Reetu Sharma Khageshwar Singh Patel +1 位作者 Lesia Lata Huber Milos 《Journal of Environmental Protection》 2017年第3期358-379,共22页
The pond water is used by a variety of animals i.e. mammals, birds, duck, and fish. Sediments play a significant role in determining the overall environmental quality for the living organism. Therefore, in this work, ... The pond water is used by a variety of animals i.e. mammals, birds, duck, and fish. Sediments play a significant role in determining the overall environmental quality for the living organism. Therefore, in this work, chemical characterization of pond water and sediment in the largest coal burning basin of India i.e. Korba basin is described. Elements i.e. C, O, S, F, Cl, Na, Mg, Al, Si, P, K, Ca, Ti, Fe, As, Cr, Cu, Zn, Cd, Pb, and Hg were quantified. Toxic metals i.e. As, Cd, Hg, and Pb were highly enriched in the sediments, ranging from 36 - 154, 0.14 - 1.19, 0.12 - 0.82 and 26 - 127 mg/kg with mean value (p = 0.05) of 95 ± 12, 0.62 ± 0.11, 0.35 ± 0.08 and 75 ± 13 mg/kg, respectively. The concentration variations, pollution indices and sources of elements in water and sediment are discussed. 展开更多
关键词 SEDIMENT pond water CONTAMINATION IONS Metals POLLUTION Indices
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Changing water regime and adaptation strategies in Upper Mustang Valley of Upper Kaligandaki Basin in Nepal
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作者 Prem Sagar Chapagain Jagat K. Bhusal 《Research in Cold and Arid Regions》 CSCD 2013年第1期133-139,共7页
Recent climate change has brought changes to the water regime that has affected the traditional agro-pastoral production systems and livelihoods in the Upper Kaligandaki Basin of the Nepal Himalayas. Based on fieldwor... Recent climate change has brought changes to the water regime that has affected the traditional agro-pastoral production systems and livelihoods in the Upper Kaligandaki Basin of the Nepal Himalayas. Based on fieldwork and available meteorological and hydrological data, this paper examines the changing water regime and various adaptation strategies that local farmers have adopt- ed in this cold alid region. Increasing temperature and decreasing min|hll and snowfall have resulted in a negative water balance. In this scenario, lhmlers have implemented six major adaptive strategies in the trans-Himalayan Upper Mustang Valley. 展开更多
关键词 upper Kaligandaki Fanning: livelihoods climate change water balance adaptation strategies
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Water budgets for freshwater aquaculture ponds with reference to effluent volume
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作者 K. K. Sharma B. C. Mohapatra +2 位作者 P. C. Das Bikash Sarkar S. Chand 《Agricultural Sciences》 2013年第8期353-359,共7页
This paper presents the consumptive water use for freshwater pond aquaculture for semi-intensive carps farming practices. The consumptive use of water includes evaporation loss, seepage loss and water exchanges requir... This paper presents the consumptive water use for freshwater pond aquaculture for semi-intensive carps farming practices. The consumptive use of water includes evaporation loss, seepage loss and water exchanges requirements. The water requirement has been estimated to be10.3 m3/Kg of fish production under present study for semi-intensive culture and with supplemental feeding. Out of which7.6 m3/Kg of fish production is system associated requirement. On an average the evaporation loss from the pond is1498.3 mm/year and seepage loss per year is about1182.60 mm/year. Seepage and water exchange losses recharge the ground water aquifers and if they are treated and recycled, the water use in aquaculture can be reduced significantly. A further reduction in fresh water use in pond aquaculture is possible through development of intensive and superintensive culture systems and aqua feeds. 展开更多
关键词 water Budgets FRESHwater AQUACULTURE pondS CARPS SEEPAGE pond Evaporation
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Impact of Surface Water and Groundwater Pollutions on Irrigated Soil, El Minia Province, Northern Upper Egypt
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作者 Rafat Zaki Esam A. Ismail +1 位作者 Wagih S. Mohamed Ali Kamel Ali 《Journal of Water Resource and Protection》 2015年第17期1467-1472,共6页
Current research has been focused on heavy metals pollution in surface water and groundwater and effect on irrigated soil from El Minia Province, north Upper Egypt. Concentration of heavy metals (e.g., As, Co, Hg, Ni,... Current research has been focused on heavy metals pollution in surface water and groundwater and effect on irrigated soil from El Minia Province, north Upper Egypt. Concentration of heavy metals (e.g., As, Co, Hg, Ni, Se, Cd and Cr) in surface water, groundwater and irrigated soil samples is most significantly affected by leachate of many pollutants as the factories, agricultural activities, urban and natural processes. Microbiological parameters and microscopic investigations are revealed that some localities are common by micro-organisms, which are unsuitable for drinking waters. 展开更多
关键词 Heavy Metals Pollution Surface water Groundwater Soils EL Minia PROVINCE North upper EGYPT
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Water Purification Capacity of Four Kinds of Aquatic Plants in the Upper Reaches of Luanhe River
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作者 YUAN Wenge ZHENG Jianwei +2 位作者 GU Jiancai LU Guiqiao YU Xinxiao 《Journal of Landscape Research》 2018年第6期51-55,59,共6页
Under artificially simulated conditions, the water purification effects of Lythrum salicaria, Typha minima, Scirpus validus, Iris wilsonii and their configurations were studied. The results showed that various aquatic... Under artificially simulated conditions, the water purification effects of Lythrum salicaria, Typha minima, Scirpus validus, Iris wilsonii and their configurations were studied. The results showed that various aquatic plants and their configurations showed purification effects for total nitrogen(TN), nitrate nitrogen(NO_3^-), total phosphorus(TP), orthophosphate(PO_4^(3-)) and chemical oxygen demand(COD) in water body, and the purification effects of aquatic plant configurations were better than those of single ones. Regression analysis was conducted for dynamics of various water quality indicators. The removal rates of TN and COD within 50 d by the combination of L. salicaria and I. wilsonii were 73.83% and 77.4%, respectively, with the best purification effect; the removal rate of NO_3^- within 20 d by the combination of S. validus and I. wilsonii was 89.41%; and the combination of S. validus and I. wilsonii showed the best removal effect for TP and PO43-, of which the 50-d removal rates were 88.98% and 92.39%, respectively. Reasonable choice of local aquatic plants and their optimal combinations can be applied in the improvement of water quality of rivers. 展开更多
关键词 upper reaches of Luanhe RIVER AQUATIC PLANTS CONFIGURATION water PURIFICATION
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