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Environmental impact of aquaculture-sedimentation and nutrient loadings from shrimp culture of the southeast coastal region of the Bay of Bengal

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Journal of Environmental Sciences 2004年第3期16卷 466-470页

作者： Biplob Das Yusuf Sharif Ahmed Khan Pranab Das Department of Earth and Atmospheric Sciences Institute of Marine SciencesInstitute of Marine Sciences 1-26 Earth Sciences Building University of Alberta Edmonton Alberta T6G 2E3CanadaUniversity of ChittagongChittagong 4331BangladeshUniversity of ChittagongChittagong 4331Bangladesh

Nutrient loadings were measured for surface seawater and bottom sediments of semi intensive and improved extensive shrimp culture pond, adjacent estuary, and fallow land in the south east coastal region of Bangladesh during August, 2000—January, 2001 to evaluate the impact of shrimp culture. The mean levels of nutrients found in the pond surface water were 108 780 mg/L for CaCO 3, 0 526 mg/L for NH + 4 N, 3 075 wt% for organic carbon, 7 00 mg/L for PO 4 P, 5 57 mg/L for NO 3 N, and 7 33 mg/L for chlorophyll a. The maximum mean value of H 2S(0 232 mg/L) was found in estuarine water. Nutrients loading were found to be decreased with distance from the shrimp farm discharge unit in estuarine water. The mean level of organic matter, total nitrogen, and organic carbon were found in higher concentrations in sediments of cultured pond compared to bottom soil of adjacent fallow land at the same elevation. Extractable Ca values were found in higher concentration(550 33 ppt) in adjacent fallow land, as the shrimps for molting in shrimp ponds use extractable Ca. The relation between seawater H 2S value and sediment pH ( r= -0 94); sediment organic carbon and sediment pH values ( r= -0 76), sediment total nitrogen and sediment pH ( r= - 0 74) were found to be highly negatively correlated. Whereas the relation between seawater H 2S value and sediment total nitrogen ( r= 0 92), water NH + 4 N and sediment pH ( r= 0 66) were found to be positively correlated. The results revealed that load of nutrients at eutrophic level in estuarine water, and decrease of soil pH; leading to acid sulphate soil formation indicates a negative impact of shrimp culture.

关键词： environment eutrophication impact nutrients shrimp culture

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Bacterial and eukaryotic community interactions might contribute to shrimp culture pond soil ecosystem at different culture stages

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Soil Ecology Letters 2022年第2期4卷 119-130页

作者： Renjun Zhou Hao Wang Dongdong Wei Shenzheng Zeng Dongwei Hou Shaoping Weng Jianguo He Zhijian Huang State Key Laboratory of Biocontrol Southern Marine Sciences and Engineering Guangdong Laboratory(Zhuhai)School of Marine SciencesSun Yat-sen UniversityGuangzhou 510275China Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

Sedimentary bacterial and eukaryotic communities are major components of the aquatic *** the linkages between their community structure and interactions is crucial to understand the diversity and functions of aquatic and soil ***,how their diversity and assembly contribute to their interactions on time scale is *** study examined sedimentary bacterial and eukaryotic communities in shrimp culture ponds at different culture *** most abundant bacteria were Proteobacteria(38.27%),whereas the most abundant eukaryotes were Chytridiomycota(27.48%).Bacterial and eukaryotic diversities were correlated(Pshrimp *** the eukaryotic community significantly increased in similarity along with the shrimp culture(Pshrimp ***-occurrence network modeling indicated that positive microbial interactions were *** homogeneous selection was the major driver of community *** diversity negatively correlated with operational taxonomic units and positive links in networks(Pculture production.

关键词： Sediment shrimp culture Bacteria Eukaryotes Microbial community

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A gradient-based stochastic search approach for optimal harvesting strategy in shrimp culture 36

A gradient-based stochastic search approach for optimal harv...

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第36届中国控制会议

作者： Wu Xiang Liu Qiaodan Lei Bangjun Zhang Kanjian School of Mathematical Sciences Guizhou Normal University School of Electrical Engineering Southeast University School of Electrical and Information Engineering Guizhou Institute of Technology School of Automation Southeast University

ISBN: (纸本)9781538629185

This paper considers an optimal harvesting strategy problem arising in shrimp culture. The problem is formulated as an optimal control problem of nonlinear impulsive system. Since the impulsive switching constraints is very complex, the impulsive switching instants are unknown, and the objective function is not continuously differentiable, it is difficult to solve this problem by standard optimization methods. To overcome the difficulty, by introducing a novel binary variable for each sale price of shrimp, relaxing the binary variable, and imposing a penalty function on the relaxation term, the nonlinear impulsive system optimal control problem is transformed into a parameter optimization problem, which can be solved efficiently using any gradient-based optimization technique. Then, a gradient-based stochastic search approach is proposed for solving this ***, a harvesting strategy problem is presented to illustrate the efficiency of the approach proposed.

关键词： Optimal control Nonlinear impulsive system Binary novel variable Penalty function shrimp culture

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Assessment of Water Quality in shrimp culture Areas of the Mekong Delta

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Journal of Agricultural Science and Technology(B) 2014年第7期4卷 571-580页

作者： Vu Ngoc Ut Nguyen Ba Quoc Son Sam Phone College of Aquaculture and Fisheries Can Tho University Can Tho City 70 000 Vietnam

Water quality was investigated in shrimp culture areas in Cau Ngang, Tra Vinh where three culture systems were found in the same area to assess the impact of intensification of shrimp culture on the surrounding environment. Three culture systems were selected including intensive, semi-intensive and rice-shrimp alternated culture for the study. Monthly assessment of physical and chemical parameters of water and biotic parameters were done for a period of one year from March, 2009 to February, 2010 in the canals surrounding the culture systems. The physical chemical parameters of water recorded include temperature, pH, dissolved oxygen, chemical oxygen demand （COD）, total suspended solids （TSS）, total ammonium （TAN）, nitrite （N-NO2）, nitrate （N-NO3） and total nitrogen （TN）, total phosphorus （TP） in both water and sediment. Zooplankton and zoobenthos were determined quantitatively and qualitatively using zooplankton nets and Petersen grabs, respectively. The results indicated that most of water parameters were not significantly different between culture systems and were in suitable ranges for aquatic life within the national standard criteria except DO, TSS and TP at some periods. DO concentration in rice-shrimp system was significantly lower than that in other systems. TSS and TP concentrations both in water and sediment were high exceeding the limit ranges （〉 100 mg/L）. The occurrence of some zooplankton and zoobenthos species indicated that all systems were polluted at 13 level （mesosaprobic） in which the rice-shrimp alternated culture system subjected to more environmental fluctuation not only by shrimp culture but also rice cultivation and salinity variation between dry and rainy seasons.

关键词： Water quality shrimp culture bio-indicators.

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COMPARATIVE STUDIES ON NITROGEN BUDGETS OF CLOSED shrimp POLYculture SYSTEMS

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Chinese Journal of Oceanology and Limnology 2001年第3期19卷 233-242页

作者：齐振雄李德尚张曼平董双林 Ocean University of Qingdao Qingdao China

April to October, 1997 comparative studies on the nitrogen budgets of closed shrimp polyculture systems showed that, in all the studied polyculture systems, nitrogen from feeds and fertilizers were the main input items, which comprised 70.7%-83.9% of the total input nitrogen, 3.2%-7.4% of which was provided by nitrogen fixation. It was in monoculture enclosures (Y 4, Y 11 and Y 12) that the percentage reached the maximum value. The output nitrogen in harvested products comprised 10.8%-24.6% of total input nitrogen, and the highest percentage, 24.6%, was found in shrimp fish tagelus polyculture systems. In shrimp monoculture and shrimp fish polyculture systems, they were 19.1% and 21.9%, respectively. The nitrogen utilization efficiency was different and varied from 12.2% to 20.1%. The highest, 20.1%, was found in shrimp fish tagelus polyculture systems, and the average of 20.0% was found in shrimp tagelus polyculture systems. The lowest, 12.2%, was found in shrimp monoculture systems. All the nitrogen utilization efficiencies in shrimp fish systems or shrimp scallop systems seemed to be higher than that of the monoculture system, but they showed little statistical difference. The main outputs of nitrogen were found in sediment mud, and comprised 48.2%-60.8% of the total input, the lowest percentage was found in shrimp fish tagelus polyculture systems, and the highest percentage in shrimp scallop systems. During the experiment, nitrogen lost through denitrification and ammonia volatilization comprised 1.9%-6.2%, averaged 2.8%, of the total input, and the loss through seepage comprised 5.9%-8.9% of the total. The estimated nitrogen attached to the enclosure wall comprised 3.7%-13.3% of the total, and was highest in shrimp monoculture systems. Compared with the classic shrimp farming industry, the closed shrimp polyculture systems may improve the nitrogen utilization efficiency, and hence reduce the environmental impacts on coastal waters. The nitrogen discharging rate

关键词： nitrogen budget shrimp culture polyculture system

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Assessment of nitrogen and sulphur cycle bacteria and shrimp production in ponds treated with biological products

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Journal of Coastal Life Medicine 2015年第6期 466-470页

作者： Thangapalam Jawahar Abraham Shubhadeep Ghosh Debasis Sasmal Department of Aquatic Animal Health Faculty of Fishery SciencesWest Bengal University of Animal and Fishery SciencesKolkata 700094India

Objective:To study the influence of biological products on the levels of nitrogen and sulphur cycle bacteria in shrimp culture systems of West Bengal,***:The pond water and sediment samples were analyzed for physico-chemical parameters as per standard *** bacteria involved in ammonification,nitrification,denitrification,sulphate reduction and sulphur oxidation were enumerated by most probable number ***:The semi-intensive and modified extensive shrimp farms used a variety of biological products during various stages of *** biological products were used in traditional *** water and sediment samples of modified extensive system recorded significantly higher mean heterotrophic bacterial *** counts of ammonia,nitrite and sulphur oxidizers,and nitrate and sulphate reducers varied among the *** cycling of nitrogen and sulphur appeared to be affected with the intensification of culture ***:The application of biological products in certain systems helped to maintain the bacteria involved in nitrogen and sulphur cycles and safe levels of ammonia,nitrite and *** assessment of these metabolically active bacteria in shrimp culture ponds and the application of right kind microbial products would help ameliorate the organic pollution in shrimp aquaculture.

关键词： shrimp culture Biological products Heterotrophic bacteria Nitrogen cycle bacteria Sulphur cycle bacteria

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A Unit Study of Externality of shrimp Farming on Provisioning Services (Paddy Farming)

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NASS Journal of Agricultural Sciences 2019年第2期1卷 13-18页

作者： Suvendu Das Prosenjit Saha Arnab Banerjee Manaswee Maity Santanu Ray Systems Ecology&Ecological Modelling Laboratory Department of ZoologyVisva-Bharati UniversitySantiniketan731235India Department of Geography Memari CollegeMemariBurdwan713146India Department of Mathematics Jadavpur UniversityKolkata700032India

Externality;the term can define as a positive or negative impact from either production or consumption of goods or *** provided by particular location have very specific dependency on spatial characteristics of that region.A region’s distinct characteristics make it ecologically unique from other such *** services are offered by these regions thus differ according to these unique ecological *** this particular study,artificially imposed expansion of coastal shrimp farming towards the inland and its impact over paddy cultivation have been *** of the extent of this manipulative coastal expansion has been supported by little modification of a previously described *** the investment prediction for both shrimp and paddy farming has been investigated by calculating net present value(NPV).shrimp farming has very specific externality on local ecosystem *** this particular case,some contradictory results are presented and with respect to positive or negative externality;but the externalities are *** results indicate that there is no long-term profitability in case of shrimp ***,an overall externality of shrimp farming has been described in context of this study.

关键词： shrimp culture Altered ecosystem services Paddy farming Spatial influence Net Present Value Externality

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Effect of polyculture of shrimp with fish on luminous bacterial growth in grow-out pond water and sediment

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Journal of Coastal Life Medicine 2014年第6期 438-441页

作者： Thangapalam Jawahar Abraham Department of Aquatic Animal Health Faculty of Fishery SciencesWest Bengal University of Animal and Fishery SciencesKolkata-700094West BengalIndia

Objective:To study the distribution of marine luminous bacteria in shrimp culture systems of West Bengal and the effect of polyculture of shrimp with fish to reduce luminous ***:Luminous bacterial counts were enumerated by spread plating on seawater complex agar from shrimp grow-out pond water and pond sediment samples of West Bengal,***:About 31.16%and 51.44%of pond sediment and pond water samples respectively had detectable levels of luminous *** was noticed that in normal ponds a shift happened in bacterial profile of water from the day of flooding up to 60 d,with the dominance of luminous bacteria among vibrios,reaching counts 10^(4) cells/mL or *** in diseased ponds,luminous bacterial abundance within the ponds was noticed in the first 6 weeks of *** reduction in luminous bacterial counts of water and sediment was observed through out the culture period in polyculture ponds compared to monoculture *** was no incidence of white spot syndrome viral disease and luminous vibriosis in both controlled and experimental ***:The results suggest vigilant monitoring of ponds for luminous bacteria abundance and polyculture of shrimp with fish in ecofriendly sustainable aquaculture can reduce the impact of shrimp disease outbreak.

关键词： shrimp culture Luminous bacteria Biological treatments Polyculture

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