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Spatio-Temporal Patterns of Nitrogen and Phosphorus Stoichiometry in Cascade Ponds in an Agricultural Small Watershed and Their Influencing Factors
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作者 Jiaogen Zhou 《Journal of Water Resource and Protection》 CAS 2022年第12期759-772,共14页
Ecological stoichiometry of nitrogen and phosphorus is an important indicator to characterize the nitrogen and phosphorus trophic status in aquatic ecosystems. The study of the spatio-temporal patterns of nitrogen and... Ecological stoichiometry of nitrogen and phosphorus is an important indicator to characterize the nitrogen and phosphorus trophic status in aquatic ecosystems. The study of the spatio-temporal patterns of nitrogen and phosphorus stoichiometry is beneficial to the nitrogen and phosphorus pollution management in pond ecosystems. In this study, 18 groups (36 in total) of typical cascade ponds were selected as long-term observations to investigate the spatial distribution patterns of nitrogen and phosphorus component ratios (ratio of total nitrogen to phosphorus: TN:TP, ratio of dissolved nitrogen to phosphorus: TDN:TDP, ratio of particulate nitrogen to phosphorus: PN:PP) in water bodies in the tropical agricultural watershed of Jinjing. The results showed that the average values of TN:TP and TDN:TDP in the upstream ponds were 26.4 and 53.4, respectively, and were more than those in the downstream (22.95 and 48.1, respectively). In contrast, the PN:PP (13.78) in the upstream was significantly lower than that of the downstream (30.39). Furthermore, the factors of rainfall, agricultural land use and fish farming influenced the spatio-temporal variability of the N:P ratios. The ratios of TN:TP and TDN:TDP were higher in the wet season and lower in the dry season. Agricultural land use and fish farming reduced the ratios of the above three nitrogen and phosphorus components in cascade ponds in the study area. Our results show that strengthening agricultural land pollution control and aquaculture management could help to improve water quality of pond ecosystems in the study area. 展开更多
关键词 Agricultural Land Use fish Farming pond Ecosystems Nitrogen and Phosphorus Component Nitrogen and Phosphorus Stoichiometry
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The Influence of Land Use and Fish Farming on the Contents of Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup>and Na<sup>+</sup>in Pond and Reservoir Ecosystems in an Agricultural Small Watershed, China
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作者 Jiaogen Zhou Caiyun Zhang 《Journal of Environmental Protection》 2021年第12期1174-1184,共11页
It is not understood well that how the effects of land use and fish farming on the contents of alkali metals (Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</... It is not understood well that how the effects of land use and fish farming on the contents of alkali metals (Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</sup>) in small water bodies of pond and reservoir ecosystems at the watershed scale. In this study, the concentrations of Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup> and Na<sup>+</sup> in water bodies were measured for 103 ponds and reservoirs used as fish farming or surrounded by different agricultural land use types in the subtropical hilly watershed of Jinjing (105 km<sup>2</sup>), China. The two important environmental factors of fishing farming and agricultural land use influenced the spatial variation the contents of alkali metals. The ponds and reservoirs in residential area had significantly higher concentrations of Ca<sup>2+</sup> and Na<sup>+</sup> than those with other land use types, reflecting the influence of domestic wastewater. Compared with those of natural ponds with non-fish farming, no significant increase of alkali metal contents occurred in fish farming ponds, due to the regular cleaning of ponds by farmers. However, the effect of fish culture on alkali metal contents was still supported indirectly by the fact that the alkali metal contents significantly correlated with nitrate contents in fish farming ponds and but high related with that of DIP in natural ponds. The suitability assessment for irrigation on the pond water indicated that almost all of ponds were suitable for irrigation except some ponds surrounded by residential area and tea plantation. Generally, our results demonstrated that fish farming and agricultural land use affected the contents of alkali metals in ponds and reservoirs. The agricultural water irrigation would be with caution from the ponds with tea plantation and residential area in the subtropical hilly watershed. 展开更多
关键词 Land Use Alkali Metals fish Farming Agricultural Small Watershed pond and Reservoir
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Eco-drainage Pond in Non Irrigated Land for the Conservation of Land and Water Based on Community Participation
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作者 Dwi Tjahjanto Sriyana +3 位作者 Sobri Harun Zulhilmi Ismail Arien Heryansyah Muhamad Askari 《Journal of Environmental Science and Engineering(A)》 2012年第1期92-99,共8页
There are some bad impacts from a critical land such as flood in rainy season and dryness in dry season. Long dryness could cause shortage of water for human consumption, industry and agriculture. Prevention has been ... There are some bad impacts from a critical land such as flood in rainy season and dryness in dry season. Long dryness could cause shortage of water for human consumption, industry and agriculture. Prevention has been made to avoid the both bad impacts by building hydraulic structures like reservoirs and ponds in order to reduce the peak flow during the rainy season and to store the water for use during the dry season. However, they gradually become full of sediment. This will make them work insufficiently and will cause high maintenance cost. Moreover, wells in agriculture field used as retention also suffer dryness to make crop failure. This study aims to develop a model of pond for conservation of land and water in non irrigated land. Community participation is crucial in order to solve the flood and dryness problems. The community, especially the farmers will participate actively in the implementation and maintenance of the model. There are benefits in using the pond model such as: (1) to control sediment transport to the rivers, reservoir or other hydraulic structures; (2) to reduce flood rate; (3) to increase ground water recharge; (4) to contain water for agriculture and (5) to control the fertility of land. The cost of making a unit of model (sedrainpond) of 1.5 m diameter and 1.5 meter depth is relatively cheap between $10 to $20 (US), and the maintenance is done by the farmers. When the pond model becomes functional, besides containing water in the rainy season, the water can be used to sustain water for agriculture in the dry season to avoid any crop failure. When the pond becomes dry, the farmers can harvest the suspended load sediment such as clay or silt to spread onto their land to keep its fertility. 展开更多
关键词 Model of drain eco-drainage system model of pond.
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The Relationship between the Area of Aquaculture Pond and Purification Pond in Water Circulation Aquaculture System 被引量:1
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作者 宋超 陈家长 +3 位作者 戈贤平 孟顺龙 范立民 胡庚东 《Agricultural Science & Technology》 CAS 2013年第4期684-688,共5页
The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. H... The establishment of water circulation aquaculture system realized the hi- erarchical use of nitrogen, phosphorus and other eutrophic substances in aquaculture wastewater and the recirculation use of water resource. However, no research has been reported on the detailed calculation of the relationship between the area of aquaculture pond and purification pond. In this study, referring to the absorption ability of aquatic plants to pollutants in aquaculture wastewater and pollutant generation and discharge coefficient in aquaculture pond, based on the general rules of water quality management in freshwater aquaculture system, a calculation mode was es- tablished to investigate the relationship between the area of aquaculture pond and purification pond in freshwater recirculation aquaculture system, which was feasible to explain related cases and would provide theoretical basis to reduce the economic costs in the construction of water circulation aquaculture system and realize the bal- ance between the ecological benefits and the economic benefits. 展开更多
关键词 Freshwater fish pond Recirculation aquaculture system Area of aquaculture pond Area of purification pond Calculation mode
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Perceptions of the Role Played by Aquaculture and the Services It Provides for Territories: Complementarity of Survey Types
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作者 Syndhia Mathé Hélène Rey-Valette 《Open Journal of Ecology》 2018年第4期270-285,共16页
This article discusses the perception of ecosystem services for French and Brazilian pond fish farming. Its aim is to study the extent to which the industry and its stakeholders are aware of the existence of such serv... This article discusses the perception of ecosystem services for French and Brazilian pond fish farming. Its aim is to study the extent to which the industry and its stakeholders are aware of the existence of such services in order to be able to prioritize them with respect to social well-being. This identification phase is seldom discussed. It requires that survey questionnaires be designed so as to improve understanding of these perceptions. The surveys undertaken combined both open questions where the interviewees expressed their perceptions spontaneously and closed questions where they were invited to rank a pre-established list of the relevant services. These surveys involved 133 fish farmers and 93 stakeholders. The results show that perceptions differ by question type, and confirm the significance of the questionnaire design and the importance of combining several kinds of approach. 展开更多
关键词 Ecosystem SERVICES pondS fish FARMING QUESTIONNAIRE Design France Brazil
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Approximate Compositional Values and Tissue Fatty Acid Profiles of Nile Tilapia (<i>Oreochromis niloticus</i>L.) Fed <i>Azolla</i>-Diets in Earthen Ponds
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作者 Youssouf Abou Emile Didier Fiogbé +1 位作者 Yves Beckers Jean-Claude Micha 《Food and Nutrition Sciences》 2011年第9期964-973,共10页
The approximate general composition and the fatty acid profile of Nile tilapia fed Azolla-diets in ponds were studied for 90 days. Six isonitrogenous (29.2% CP) and isoenergetic (16.9 kJ·g>sup>-1) diets wer... The approximate general composition and the fatty acid profile of Nile tilapia fed Azolla-diets in ponds were studied for 90 days. Six isonitrogenous (29.2% CP) and isoenergetic (16.9 kJ·g>sup>-1) diets were formulated to contain 0% (A0), 10% (A10), 20% (A>sub>20), 30% (A30), 40% (A40) and 50% (A50) of Azolla meal (AM), as partial fish meal (FM) substitutes. Diet A0 without AM served as a control. Fish growth decreased as AM level exceeded 20% in diets (P 0.05). Crude lipid was significantly lower in fish fed A50 and significant differences were also found in crude ash (P 20, A30 and A50. High level of the fern reduces growth without negatively affecting fatty acid in fish. Fish PUFA, especially the (n - 3) fatty acids, are affected positively, even when fed 50% AM, which is good for the quality of the fish produced in regard to the benefits for the health of consumers. 展开更多
关键词 AZOLLA Filiculoides fish Meal Replacement OREOCHROMIS NILOTICUS Fatty Acid Natural Food Earthen pond
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Influence of Management on the Water Quality and Sediment in Tropical Fish Farm
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作者 Lúcia H.Sipaúba-Tavares Rodrigo N.Millan Atanásio A.do Amaral 《Journal of Water Resource and Protection》 2013年第5期495-501,共7页
A seven-month research evaluated the management effect on the water quality and sediment of seven fish ponds. Water and sediment were collected at nine sample sites: seven in the fish ponds;one in inlet water and anot... A seven-month research evaluated the management effect on the water quality and sediment of seven fish ponds. Water and sediment were collected at nine sample sites: seven in the fish ponds;one in inlet water and another in the fish farm’s effluent. The soil samples were analyzed for macro- and micro-nutrients and the water samples were analyzed for physical and chemical parameters. Management and local climate conditions affected nutrient seasonality in the sediment and featured high concentrations of Al, Ca, Cu, K, Mg, C, Na, Zn and OM at the effluent with low pH, ranging between 4.4 and 6.5. Sudden decrease of DO (less than 3 mg/L) during the rainy season, with a 180 mmrainfall, and a TSS increase (approximately 10 mg/L) were reported. Use of organic manure in fish pond V6 caused higher rates of ammonia (over 1 mg/L). Due to the sediment’s acid pH (less than 4.8) and Al at 0.92 mg/L at the effluent, great care was required in the fish farm. Maintenance and procedures management in the fish farm under analysis should be given more attention since high levels of Al, Fe and acid pH and low levels of potassium and phosphorus in the sediment may produce unfavorable conditions in the water column, and may ultimately have an impact on fish. 展开更多
关键词 Water Quality fish ponds MANAGEMENT SEDIMENT
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The Development of a Renewable-Energy-Driven Reverse Osmosis System for Water Desalination and Aquaculture Production 被引量:1
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作者 Clark C K Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1357-1362,共6页
Water and energy are closely linked natural resources - the transportation, treatment, and distribution of water depends on low-cost energy; while power generation requires large volumes of water. Seawater desalinatio... Water and energy are closely linked natural resources - the transportation, treatment, and distribution of water depends on low-cost energy; while power generation requires large volumes of water. Seawater desalination is a mature technology for increasing freshwater supply, but it is essentially a trade of energy for freshwater and is not a viable solution for regions where both water and energy are in short supply. This paper discusses the development and application of a renewable-energy-driven reverse osmosis (RO) system for water desalination and the treatment and reuse of aquaculture wastewater. The system consists of (1) a wind-driven pumping subsystem, (2) a pressure-driven RO membrane desalination subsystem, and (3) a solar-driven feedback control module. The results of the pilot experiments indicated that the system, operated under wind speeds of 3 m s-~ or higher, can be used for brackish water desalination by reducing the salinity of feedwater with total dissolved solids (TDS) of over 3 000 mg L-1 to product water or permeate with a TDS of 200 mg L-~ or less. Results of the pilot experiments also indicated that the system can remove up to 97% of the nitrogenous wastes from the fish pond effluent and can recover and reuse up to 56% of the freshwater supply for fish pond operation. 展开更多
关键词 renewable energy DESALINATION pressure-driven membrane processes AQUACULTURE fish pond
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Effects of Rice-Fish Co-culture on Oxygen Consumption in Intensive Aquaculture Pond 被引量:5
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作者 LI Fengbo SUN Zhiping +6 位作者 QI Hangying ZHOU Xiyue XU Chunchun WU Dianxin FANG Fuping FENG Jinfei ZHANG Ning 《Rice science》 SCIE CSCD 2019年第1期50-59,共10页
Rice-fish co-culture has gained increasing attention to remediate the negative environmental impacts induced by intensive aquaculture. However, the effect of rice-fish co-culture on oxygen depletion has rarely been in... Rice-fish co-culture has gained increasing attention to remediate the negative environmental impacts induced by intensive aquaculture. However, the effect of rice-fish co-culture on oxygen depletion has rarely been investigated. We constructed a rice-fish co-culture system in yellow catfish(Pelteobagrus fulvidraco) and freshwater shrimp(Macrobrachium nipponense) ponds using a new high-stalk rice variety, and conducted a field experiment to investigate the effect of rice-fish co-culture on water parameters and oxygen consumption. The results showed that rice-fish co-culture reduced the nutrients(total nitrogen, ammonia-N, total phosphorous and potassium) and the dissolved oxygen content in fish and shrimp ponds. However, they showed similar seasonal change of dissolved oxygen in the water of fish and shrimp ponds. Rice-fish co-culture reduced the total amount of oxygen consumption and optimized the oxygen consumption structure in pond. The respiration rates in water and sediment were significantly reduced by 66.1% and 31.7% in the catfish pond, and 64.4% and 38.7% in the shrimp pond, respectively, by additional rice cultivation. Rice-fish co-culture decreased the proportions of respiration in sediment and water, and increased the proportion of fish respiration. These results suggest that rice-fish co-culture is an efficient way to reduce hypoxia in intensive culture pond. 展开更多
关键词 rice-fish CO-CULTURE oxygen depletion respiration pond aquaculture yellow CATfish FRESHWATER shrimp
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Model of Wetland Carbon Sequestration in the Venetian Lagoon, Italy 被引量:1
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作者 Mauro Doimi Angelo Ferrari +1 位作者 Daniele DalMolin Italo Gardan 《Journal of Environmental Science and Engineering(B)》 2013年第11期657-671,共15页
This research deals with an evaluation of the sink of greenhouse gas CO2 in a eutrophic area of the Venetian lagoon where fish is farmed ("Valle da pesca"). Following CDM UNFCCC (Clean Development Mechanism Unite... This research deals with an evaluation of the sink of greenhouse gas CO2 in a eutrophic area of the Venetian lagoon where fish is farmed ("Valle da pesca"). Following CDM UNFCCC (Clean Development Mechanism United Nations Framework Convention on Climate Change) criteria, this can be considered relevant to the international standard for the voluntary evaluation of carbon credits on the basis of Annex a of Kyoto Protocol. To identify the "Valle da pesca" brackish lagoon properties regulating the carbon dioxide (CO2), a survey has been performed during three seasons in one year and in four different locations. These places are located in the Italian Venetian Lagoon and in the Grado Lagoon in North Italy, Europe. To identify the CO2 sink capacity, a special index is calculated. The CO2 concentrations and sink are regulated by the balance of autotrophic and heterotrophic activities, and the sediment anoxic denitrification and macro algae are crucial tank of CO2 in the valley shallow waters. The ponds potential-CO2 yield of 80-124 kg/m2 per year and the value are related and proportional to the correct human environmental control (water flux control). 展开更多
关键词 Carbon sink LAGOON fish ponds Valle da pesca Italy.
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Mathematical Equations for Reducing Water Pollution Problems among Poultry Production Clusters in Nong Khai Province, Thailand
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作者 Worapol Aengwanich Thongchai Boonsorn Komvut Thammasar 《Journal of Geoscience and Environment Protection》 2014年第2期48-51,共4页
Poultry production clusters (PPC) in Nong Khai raise layer chickens in the poultry houses constructed over fish ponds. Layer farmers use chicken manure to feed their fish. However, unbalance between chicken raising an... Poultry production clusters (PPC) in Nong Khai raise layer chickens in the poultry houses constructed over fish ponds. Layer farmers use chicken manure to feed their fish. However, unbalance between chicken raising and the size of fish pond or number of fish results in low water quality, which affects fish production and the community’s public water resource. In this field study, data was collected from layer farms in three poultry production clusters in Nong Khai province in the northeast of Thailand (a total of 90 farms) between April and August 2013. Data collected consisted of observations of dissolved oxygen (DO) values of water in the fish ponds, the number of egg-laying chickens raised above the fish ponds, the number of fish and size of the fish ponds. When all of these four observations were analyzed, mathematical equations for calculating the number of chickens raised, the number of fish per one rai (1600 m2), and the size of pond suitable for the number of chickens and fish were obtained as follows: 1) number of fish/rai = 5796 + 1097(size of pond) (R2 = 0.71), 2) number of chicken/rai = 513 + 223(size of pond) (R2 = 0.48) and 3) size of pond =-0.328474 + 0.000262(Fish) + 0.00117(Chicken) (R2 = 0.40). When pond = desired pond size, fish = number of fish to be raised and chicken = number of chickens to be raised. 展开更多
关键词 Mathematic Equation Water Pollution POULTRY Production CLUSTERS PPCS fish pond Thailand
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Metal Concentration in Muscle Tissue of Carp and Pike from Different Fish Ponds in Belgrade Area
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作者 Jelena Janjie Jelena Ivanovic +4 位作者 Radmila Markovic Marija Starcevic Marija Boskovic Vesna Dordevic Milan Baltic 《Journal of Agricultural Science and Technology(B)》 2015年第6期429-436,共8页
This study was conducted to determine the contamination data of some heavy metals in 10 fish tissue samples of two different fish species---common carp and Northern pike from four different fish ponds and to compare t... This study was conducted to determine the contamination data of some heavy metals in 10 fish tissue samples of two different fish species---common carp and Northern pike from four different fish ponds and to compare the level of contamination and the differences in the concentration of these elements between these two fish species and between compared fish ponds. In various fish ponds, metal concentrations in the carp muscle tissue varied depending on the metal type. Between compared fish ponds, there were significant differences (P 〈 0.01) in the concentration in muscle carp tissue, except for cadmium. Metal concentrations in the pike muscle tissue also varied among fish ponds, depending on the type of metal. In all compared cases, there were significant differences between metal concentration in pike muscle tissue (P 〈 0.01). Lead and cadmium concentration in pike muscle tissue were significantly higher (P 〈 0.01, P 〈 0.05, respectively), and mercury and arsenic concentration were significantly lower (P 〈 0.01) than concentration of this heavy metals in carp muscle tissue in all comapered fish ponds. The results obtained in this study indicate variation in a range of examined metal concentration in muscle tissue, which seems to be typical for the Serbian fish ponds, but is lower than those in rivers with considerable anthropogenic impact. 展开更多
关键词 Common carp fish pond metal concentration Northern pike.
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Treatise by Olbrycht Strumieński (1573)--The First Polish Book on Hydraulic Engineering
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作者 Małgorzata Taborska 《Journal of Physical Science and Application》 2019年第2期30-38,共9页
The treatise by Olbrycht Strumieński is chronologically the first book in Poland, and the second in Europe, describinglevelling instruments. A few years after Strumieński’s death, the text was published by Stanisła... The treatise by Olbrycht Strumieński is chronologically the first book in Poland, and the second in Europe, describinglevelling instruments. A few years after Strumieński’s death, the text was published by Stanisław Stroynowski. Until the 19th century,only three Polish-language treatises addressed the problems of levelling. Strumieński described the technique of building andmanaging fish ponds in Moravia, Bohemia and Poland. The presented surveying instruments and measuring methods are sufficientfor the design and construction of a pond that can survive for over 300 years. Strumieński also presented the principles of freshwateraquaculture. Poland, along with Bohemia, Moravia and Hungary, was an exporter of freshwater fish to Western Europe from the 16thto the mid-18th century. 展开更多
关键词 levelling instruments levelling treatise fish ponds
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基于物联网的智能鱼塘水质环境监测系统设计
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作者 赵志阳 张宸瑞 +1 位作者 赵轩毅 高明阳 《无线互联科技》 2024年第17期21-23,共3页
文章设计并实现了一种基于STM32的智能鱼塘水质环境监测系统。该系统旨在通过实时监测鱼塘水质参数,如温度、溶解氧、pH值、氨氮和亚硝酸盐,提供科学的养殖环境管理支持。系统硬件包括STM32微控制器、各类传感器、LCD显示屏和PC端软件,... 文章设计并实现了一种基于STM32的智能鱼塘水质环境监测系统。该系统旨在通过实时监测鱼塘水质参数,如温度、溶解氧、pH值、氨氮和亚硝酸盐,提供科学的养殖环境管理支持。系统硬件包括STM32微控制器、各类传感器、LCD显示屏和PC端软件,软件架构则涵盖数据采集、处理、传输及用户界面模块,最后的实验结果验证了系统的有效性。 展开更多
关键词 物联网 智能鱼塘 STM32 水质监测
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长江流域2种水产养殖模式的生命周期环境影响评价 被引量:1
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作者 董寅 李冰 +3 位作者 贾睿 侯诒然 刁维旭 朱健 《渔业科学进展》 CSCD 北大核心 2024年第1期23-32,共10页
本研究以长江流域内的池塘养殖和稻渔综合种养2种水产养殖模式为对象,应用生命周期评价方法,分析2种养殖模式对能源消耗(EU)、全球变暖潜势(GWP)、酸化潜势(AP)、富营养化潜势(EP)以及水资源消耗(WU)5种环境指标的影响,并探究2种主要输... 本研究以长江流域内的池塘养殖和稻渔综合种养2种水产养殖模式为对象,应用生命周期评价方法,分析2种养殖模式对能源消耗(EU)、全球变暖潜势(GWP)、酸化潜势(AP)、富营养化潜势(EP)以及水资源消耗(WU)5种环境指标的影响,并探究2种主要输入因子(饲料和电力供应)和养殖过程对各环境指标的影响,从而评价2种养殖模式对环境影响的差异。生命周期评价结果标准化处理和加权评估显示,稻渔综合种养模式的WU、EP、GWP、AP和EU值分别为11.650、0.770、0.141、0.096和0.003,总环境影响指数(TEII)为12.660;池塘养殖模式的WU、EP、GWP、AP和EU值分别为31.453、1.187、0.210、0.174和0.007,TEII为33.031。与稻渔综合种养模式相比,池塘养殖模式的各项环境指标均较高。对环境影响的贡献率分析表明,饲料供应对EU、GWP和AP的贡献率最高,EP主要受饲料供应和养殖过程的共同影响,而WU主要集中在养殖过程中,电力供应主要影响EU、GWP和AP。生命周期评价的结果表明,与池塘养殖模式相比,稻渔综合种养模式显示出更友好的环境效益,在我国长江流域具有较大的发展空间。2种养殖模式的贡献率分析表明,改进饲料生产工艺、建立精准投喂技术、应用先进的尾水处理技术和适当提高养殖密度是我国长江流域水产养殖环境友好生产的关键。 展开更多
关键词 稻渔综合种养 池塘养殖 生命周期评价 环境影响
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气象条件对夏季鱼塘溶氧垂直变化影响及对策研究
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作者 刘可群 邓爱娟 +2 位作者 孟翠丽 李伟 汤阳 《农学学报》 2024年第8期81-88,共8页
鱼塘溶氧垂直差异大小是健康生态养殖的重要指标之一。基于湖北洪湖2022年6月21日—7月14日鱼塘溶氧、水温、光强等上下垂直分层观测资料,以及同步地面气象观测资料,分析了鱼塘水体溶氧日变化特征,在排除了人为因素干扰相关资料后,采用... 鱼塘溶氧垂直差异大小是健康生态养殖的重要指标之一。基于湖北洪湖2022年6月21日—7月14日鱼塘溶氧、水温、光强等上下垂直分层观测资料,以及同步地面气象观测资料,分析了鱼塘水体溶氧日变化特征,在排除了人为因素干扰相关资料后,采用统计回归方法,诊断分析了上下层溶氧差异与气象环境因子关系。结果表明:夏季晴好天气下,随进入水体的光照增强,上层溶氧常处于饱和或过饱和,下层处于低溶氧状态;120 cm层溶氧增量与光强呈不显著的负相关,鱼塘下层难以通过光合产氧满足底层鱼类溶氧需求。鱼塘水体温度上高下低的垂直梯度会阻碍氧向下迁移,在30 cm与60 cm两层水温相差1℃的情况下,其溶氧量差可达6.6 mg/L。在风的作用下,风力越大,上下层水温差异越小,迁移阻力小、迁移快,溶氧差异小;地面极大风速达9 m/s以上时,鱼塘上下层的溶氧差异小,无需人工干预增氧。打破水温垂直梯度变化是确保夏季鱼塘良好生态环境重要手段,人为干预强度由风力的大小决定,风力越小,所需干预力度越大。研究结果以期为鱼塘健康养殖,降低生产成本、减少灾害损失,以及促进水产养殖智能机械化发展提供科学依据。 展开更多
关键词 夏季 鱼塘 DO 影响因子
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晋祠鱼沼飞梁结构整体稳定性分析研究
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作者 李晋芳 韩鹏举 +3 位作者 安一劲 柴琳 王崇恩 白向灵 《太原理工大学学报》 CAS 北大核心 2024年第2期316-324,共9页
【目的】晋祠鱼沼飞梁作为“世界上最古老的立交桥”,凸显着山西古建筑的文化特色。【方法】通过回弹仪对晋祠鱼沼飞梁石柱抗压强度进行测试;依据测绘图纸利用AutoCAD软件进行三维建模,并利用ABAQUS有限元分析软件对其静力荷载及地震作... 【目的】晋祠鱼沼飞梁作为“世界上最古老的立交桥”,凸显着山西古建筑的文化特色。【方法】通过回弹仪对晋祠鱼沼飞梁石柱抗压强度进行测试;依据测绘图纸利用AutoCAD软件进行三维建模,并利用ABAQUS有限元分析软件对其静力荷载及地震作用下的整体稳定性进行数值模拟分析。【结果】结果表明:鱼沼飞梁在静力作用下,构件所受应力远小于允许值,地基沉降量较小,趋于稳定;在地震作用下,结构受力均匀对称,顶面位移最大,石柱第三主应力主要集中于柱脚与柱顶,且沿地震波加载方向,斜截面发展,所受应力也小于允许值,具备较好的抗震稳定性。本研究可为鱼沼飞梁日后的保护和修缮工作提供参考依据。 展开更多
关键词 晋祠鱼沼飞梁 回弹测试 稳定性分析 有限元模拟 应力分析
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全球重要农业文化遗产桑基鱼塘时空格局演变和驱动因素
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作者 周然 游诗雪 +1 位作者 黄璐 王珂 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2024年第2期200-208,共9页
浙江省湖州市南浔区是目前桑基鱼塘保留最完整、规模最大的区域之一,该地的桑基鱼塘系统被列入全球重要农业文化遗产。随着社会经济发展、消费需求改变、农业现代化生产,桑基鱼塘系统的生产方式、经济及服务价值等发生了重大变化。本文... 浙江省湖州市南浔区是目前桑基鱼塘保留最完整、规模最大的区域之一,该地的桑基鱼塘系统被列入全球重要农业文化遗产。随着社会经济发展、消费需求改变、农业现代化生产,桑基鱼塘系统的生产方式、经济及服务价值等发生了重大变化。本文利用遥感影像、社会经济等数据对1975—2019年南浔区桑基鱼塘的时空格局演变和驱动因素进行了研究,主要结果如下:1)从规模变化上看,鱼塘快速扩张,桑园明显减少,水田剧烈萎缩,桑基鱼塘规模明显减小,基塘比例严重降低;从形态变化上看,鱼塘呈集聚化、规模化趋势,桑园和水田呈破碎化趋势,且鱼塘逐渐脱离传统桑基鱼塘系统布局特色而独立存在。2)2012—2019年,鱼塘养殖的经济效益远高于蚕桑养殖和水稻种植,是导致桑园、水田明显萎缩及鱼塘大规模扩张的主要驱动力。因此,通过全球重要农业文化遗产的建立来进一步加强桑基鱼塘系统的保护与传承是非常必要的,也是支撑湖州市南浔区农业可持续发展的重要举措。 展开更多
关键词 桑基鱼塘系统 全球重要农业文化遗产 时空格局 经济效益
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水产养殖固体废弃物有机肥对土壤肥效和蔬菜品质的影响
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作者 丁兰 徐胜南 +3 位作者 周聃 刘梅 李万祈 邹松保 《中国农学通报》 2024年第19期102-108,共7页
研究旨在探讨水产养殖固体废弃物作为有机肥料对土壤肥力和蔬菜品质的影响。通过田间小区试验,设置4个不同处理组,分别为不施肥+辣椒(CK1)、不施肥+番茄(CK2)、施鱼粪有机肥+辣椒(T_(1))、施鸡粪有机肥+辣椒(T_(2))、施鱼粪有机肥+番茄(... 研究旨在探讨水产养殖固体废弃物作为有机肥料对土壤肥力和蔬菜品质的影响。通过田间小区试验,设置4个不同处理组,分别为不施肥+辣椒(CK1)、不施肥+番茄(CK2)、施鱼粪有机肥+辣椒(T_(1))、施鸡粪有机肥+辣椒(T_(2))、施鱼粪有机肥+番茄(T_(3))、施鸡粪有机肥+番茄(T_(4)),研究鱼粪有机肥施用对土壤肥力、辣椒和番茄生长及果实品质的影响。研究结果显示,与空白对照组相比,鱼粪有机肥可以显著增加土壤微生物数量,提高土壤有机质、全氮、全磷、有效磷、孔隙度等指标数值,从而增加土壤肥力,改善土壤物理结构,促进辣椒和番茄植株生长。同时鱼粪处理组蔬菜果实维生素C含量平均提高11.9%~24.0%、可溶性糖含量提高8.1%~16.7%,果实品质显著改善、营养价值提升。然而,与市售商品鸡粪有机肥相比,还需优化相关营养成分比例配置,尤其是提高速效钾含量。 展开更多
关键词 养殖池塘 固体废弃物 水产养殖固体废弃物 有机肥 土壤肥效 土壤肥力 蔬菜品质 鱼粪、鸡粪、田间试验
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Nitrogen and Phosphorus Removal from Lake Kinneret Inputs
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作者 Moshe Gophen 《Open Journal of Ecology》 2024年第2期165-182,共18页
The Hula Valley was drained in 1957. The land use was modified from natural wetland and old shallow lake ecosystems to agricultural development. About half of the drained land area was utilized for aquaculture. Popula... The Hula Valley was drained in 1957. The land use was modified from natural wetland and old shallow lake ecosystems to agricultural development. About half of the drained land area was utilized for aquaculture. Population size was enhanced and the diary was developed intensively resulting in the enhancement of domestic and husbandry sewage production that increased as well. The natural intact Hula Valley-Lake Kinneret ecosystem was heavily anthropogenically interrupted: The Hula was drained and Kinneret became a national source for domestic water supply. Some aspects of the environmental and water quality protection policy of the system are presented. The causation and operational management implications for the reduction of Nitrogen and Phosphorus migration from the Hula Valley are discussed. Drastic (81%) restriction of aquaculture accompanied by sewage totally removed achieved a reasonable improvement in pollution control which was also supported by the Hula Project. The implications of anthropogenic intervention in the process of environmental management design are presented. 展开更多
关键词 Hula Valley JORDAN Kinneret NITROGEN PHOSPHORUS Peat Soil fish ponds Sewage Removal
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