Organic matter (OM), total nitrogen (TN), organic phosphorous (OP) and total phosphorous (TP)content of soil in northwest water-level fluctuating zone (WLFZ) of Lake Chaohu under natural and different artifi...Organic matter (OM), total nitrogen (TN), organic phosphorous (OP) and total phosphorous (TP)content of soil in northwest water-level fluctuating zone (WLFZ) of Lake Chaohu under natural and different artificial conditions were ana- lyzed to study the variation of OM, TN, OP and TP. It showed: Flooding and air- drying help to increase soil OM content in study area. Process of flooding and air- drying is conducive to soil adsorption of nitrogen and it can enhance spatial hetero- geneity of soil OM, TN, OP, process of flooding and air-drying also can reduce the difference of TP contents among different points. Riprap embankment is not con- ducive to maintaining soil organic matter under flooded conditions, emergent plants are conducive to maintaining soil organic matter under flooded conditions. Soil with high nitrogen content will release nitrogen to overlying water under flooded condi- tions. Under drying after flooding conditions, demand for phosphorus of vegetation growth will reduce TP content in soil, bare area will enrich phosphorus, when the next flood cover up a greater release of phosphorus will happen展开更多
[Objective] The aim was to study on effects of controlled release fertilizer on loss of nitrogen and phosphorus from farmland. [Method] Experiment was conducted in fields planted with rice and corn around Chao Lake an...[Objective] The aim was to study on effects of controlled release fertilizer on loss of nitrogen and phosphorus from farmland. [Method] Experiment was conducted in fields planted with rice and corn around Chao Lake and effects of compound fertilizer, controlled release fertilizer and controlled release fertilizer (reduced by 20%) on loss of nitrogen and phosphorus through runoff and leaching were analyzed. [Result] Loss of nitrogen and phosphorus mainly occurred in early stage of fertilizing; loss caused by runoff accounted for over 98% and caused by leaching was lower than 2%, indicating that nutrients of rice and corn mainly lost through runoff. As for controlled release fertilizers with 20% reduced, total loss of N and P decreased by 60% and 63% in rice field and reduced by 27.8% and 34% in corn field, respectively, indicating that controlled release fertilizer would maintain nutrients in soils high in later period of plant growth, improve use efficiency of N and P, reduce N and P loss in rice and corn fields in rainy season, and decrease non-point pollution. [Conclusion] The research suggested that controlled release fertilizer would slow down the loss of nutrients in farmlands, providing scientific references and technological support for extension of controlled release fertilizer and reduction of agricultural non-point pollution.展开更多
The research analyzed social and economic development around Chao Lake as well as changes of water quality in Chao Lake and explored the relation- ships of local population and GDP with water chemical oxygen demand (...The research analyzed social and economic development around Chao Lake as well as changes of water quality in Chao Lake and explored the relation- ships of local population and GDP with water chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), chlorophyll and eutrophication index. The re- sults showed that population around Chao Lake and GDP kept growing from 2001 to 2013, and water quality was improving. In addition, correlation analysis indicated that except of water eutrophication, GDP and population showed inverse correlation with other indices, demonstrating that water quality has been effectively controlled in Chao Lake recently.展开更多
[Objective] To study the characteristics and effects of inorganic nitrogen in east water-source and inflow rivers of Chaohu Lake. [Method] The speciation and distribution characteristics of dissolvable inorganic nitro...[Objective] To study the characteristics and effects of inorganic nitrogen in east water-source and inflow rivers of Chaohu Lake. [Method] The speciation and distribution characteristics of dissolvable inorganic nitrogen (DIN) in east water-source and inflow rivers of Chaohu Lake were investigated, and their effects on water qual- ity were examined. [Result] The concentrations of NH3-N and NO2--N were the high in flood season, and low in non-flood season, while the concentration of NO3--N pre- sented the opposite trend; the concentration of NO3--N was the highest in Shuangqiao estuary, where the pollution was the worst. DIN in Zhegao estuary and Xiaozhegao estuary was mainly caused by domestic sewage and industrial wastewaters; surface runoff and pollution from ships contribute the most to the DIN content in Shuangqiao estuary. [Conclusion] This study provided basic data and theoretical basis for the control and management of eutrophication in Chaohu Lake.展开更多
Chaohu Lake, located in the central Anhui Province, is one of the five largest fresh lakes in China. Now it is one of the three most eutrophication lakes in China. The deterioration of its water quality has influenced...Chaohu Lake, located in the central Anhui Province, is one of the five largest fresh lakes in China. Now it is one of the three most eutrophication lakes in China. The deterioration of its water quality has influenced the sustainable development of society, economy and environment of Hefei City, the capital of Anhui Province. A series of measures have been carried out to control its eutrophication, but it is still serious. On the basis of the lake water quality data from 1984 to 2003, the causes of the eutrophication of Chaohu Lake are analyzed. Studies indicated that the suitable natural conditions and human activities played a crucial role in the process of the eutrophication of Chaohu Lake. A great amount of industrial, agricultural and domestic sewage discharged into the lake is the main cause of eutrophication in the lake. Land use, soil erosion and shoreline collapse destroyed the watershed eco-environment and the terrestrial ecosystem of Chaohu Lake. And the building of Yuxi Gate extends the sluggish of the nutritious substance and speeds up the process of the eutrophication. From the view of systematic engineering and watershed ecology, a series of the countermeasures have been put forward to control the eutrophication.展开更多
Flood is one kind of unexpected and the most common natural disasters, which is affected by many factors and has complex mechanism. At home and abroad, there is still no mature theory and method used for the long-term...Flood is one kind of unexpected and the most common natural disasters, which is affected by many factors and has complex mechanism. At home and abroad, there is still no mature theory and method used for the long-term forecast of natural precipitation at present. In the present paper the disadvantages of grey GM (1, 1) and Markov chain are ana- lyzed, and Grey-Markov forecast theory about flood is put forward and then the modifying model is developed by making prediction of Chaohu Lake basin. Hydrological law was conducted based on the theoretical forecasts by grey system GM (1, 1) forecast model with improved Markov chain. The above method contained Stat-analysis, embodying scientific approach, precise forecast and its reliable results.展开更多
Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simp...Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simple and effective mathematical-ecological model to evaluate the growth status and predict the population dynamics of Microcystis blooms. In this study, phytoplankton were collected and identified from 8 sampling sites in Chaohu Lake every month from July to October, 2010. The niche breadth and niche overlap of common species were calculated using standard equations, and the potential relative growth rates of Microcystis were calculated as a weighted-value of niche overlap. In July, the potential relative growth rate was 2.79 (a.u., arbitrary units) but then rapidly declined in the following months to -3.99 a.u. in September. A significant correlation (R=0.998, P<0.01) was found in the model between the net-increase in biomass of Microcystis in the field and the predicted values calculated by the niche model, we concluded that the niche model is suitable for forecasting the dynamics of Microcystis blooms. Redundancy analysis indicated that decreases in water temperature, dissolved oxygen and total dissolved phosphorus might be major factors underlying bloom decline. Based on the theory of community succession being caused by resource competition, the growth and decline of blooms can be predicted from a community structure. This may provide a basis for early warning and control of algal blooms.展开更多
基金Supported by the Major Science and Technology Program for Water Pollution Control and Treatment(2012ZX07103-0042012ZX07103-003-03)~~
文摘Organic matter (OM), total nitrogen (TN), organic phosphorous (OP) and total phosphorous (TP)content of soil in northwest water-level fluctuating zone (WLFZ) of Lake Chaohu under natural and different artificial conditions were ana- lyzed to study the variation of OM, TN, OP and TP. It showed: Flooding and air- drying help to increase soil OM content in study area. Process of flooding and air- drying is conducive to soil adsorption of nitrogen and it can enhance spatial hetero- geneity of soil OM, TN, OP, process of flooding and air-drying also can reduce the difference of TP contents among different points. Riprap embankment is not con- ducive to maintaining soil organic matter under flooded conditions, emergent plants are conducive to maintaining soil organic matter under flooded conditions. Soil with high nitrogen content will release nitrogen to overlying water under flooded condi- tions. Under drying after flooding conditions, demand for phosphorus of vegetation growth will reduce TP content in soil, bare area will enrich phosphorus, when the next flood cover up a greater release of phosphorus will happen
基金Supported by Major Project of Control and Treatment on Domestic Water Pollution(2012ZX07103003)National 973 Project(2008CB418006)Science and Technology Foundation for Distinguished Young Schlors in Anhui Province(10040606Y30)~~
文摘[Objective] The aim was to study on effects of controlled release fertilizer on loss of nitrogen and phosphorus from farmland. [Method] Experiment was conducted in fields planted with rice and corn around Chao Lake and effects of compound fertilizer, controlled release fertilizer and controlled release fertilizer (reduced by 20%) on loss of nitrogen and phosphorus through runoff and leaching were analyzed. [Result] Loss of nitrogen and phosphorus mainly occurred in early stage of fertilizing; loss caused by runoff accounted for over 98% and caused by leaching was lower than 2%, indicating that nutrients of rice and corn mainly lost through runoff. As for controlled release fertilizers with 20% reduced, total loss of N and P decreased by 60% and 63% in rice field and reduced by 27.8% and 34% in corn field, respectively, indicating that controlled release fertilizer would maintain nutrients in soils high in later period of plant growth, improve use efficiency of N and P, reduce N and P loss in rice and corn fields in rainy season, and decrease non-point pollution. [Conclusion] The research suggested that controlled release fertilizer would slow down the loss of nutrients in farmlands, providing scientific references and technological support for extension of controlled release fertilizer and reduction of agricultural non-point pollution.
基金Supported by Anhui Environmental Protection Scientific Research Program(2014-004)~~
文摘The research analyzed social and economic development around Chao Lake as well as changes of water quality in Chao Lake and explored the relation- ships of local population and GDP with water chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), chlorophyll and eutrophication index. The re- sults showed that population around Chao Lake and GDP kept growing from 2001 to 2013, and water quality was improving. In addition, correlation analysis indicated that except of water eutrophication, GDP and population showed inverse correlation with other indices, demonstrating that water quality has been effectively controlled in Chao Lake recently.
基金Supported by the Special Fund for the Control and Management of Chaohu Lake of the National Key Technology R&D Program,China(2008ZX07103-005)the Special Fund for the Control and Management of Huaihe River of the National Key Technology R&D Program,China(2008ZX07010-004)+1 种基金National Natural Science Foundation of China(40073030,40972092,41172121)the Natural Science Foundation of Anhui Province,China(090413083)~~
文摘[Objective] To study the characteristics and effects of inorganic nitrogen in east water-source and inflow rivers of Chaohu Lake. [Method] The speciation and distribution characteristics of dissolvable inorganic nitrogen (DIN) in east water-source and inflow rivers of Chaohu Lake were investigated, and their effects on water qual- ity were examined. [Result] The concentrations of NH3-N and NO2--N were the high in flood season, and low in non-flood season, while the concentration of NO3--N pre- sented the opposite trend; the concentration of NO3--N was the highest in Shuangqiao estuary, where the pollution was the worst. DIN in Zhegao estuary and Xiaozhegao estuary was mainly caused by domestic sewage and industrial wastewaters; surface runoff and pollution from ships contribute the most to the DIN content in Shuangqiao estuary. [Conclusion] This study provided basic data and theoretical basis for the control and management of eutrophication in Chaohu Lake.
基金U nderthe auspicesofthe cooperative projectbetw een G overnm entofChina and Japan (N o.JIC A G L:SCH EFY 98)
文摘Chaohu Lake, located in the central Anhui Province, is one of the five largest fresh lakes in China. Now it is one of the three most eutrophication lakes in China. The deterioration of its water quality has influenced the sustainable development of society, economy and environment of Hefei City, the capital of Anhui Province. A series of measures have been carried out to control its eutrophication, but it is still serious. On the basis of the lake water quality data from 1984 to 2003, the causes of the eutrophication of Chaohu Lake are analyzed. Studies indicated that the suitable natural conditions and human activities played a crucial role in the process of the eutrophication of Chaohu Lake. A great amount of industrial, agricultural and domestic sewage discharged into the lake is the main cause of eutrophication in the lake. Land use, soil erosion and shoreline collapse destroyed the watershed eco-environment and the terrestrial ecosystem of Chaohu Lake. And the building of Yuxi Gate extends the sluggish of the nutritious substance and speeds up the process of the eutrophication. From the view of systematic engineering and watershed ecology, a series of the countermeasures have been put forward to control the eutrophication.
基金Under the auspices of the National Natural Science Foundation of China (No. 40571162)the Natural Science Foun-dation of Anhui Province (No. 050450401)
文摘Flood is one kind of unexpected and the most common natural disasters, which is affected by many factors and has complex mechanism. At home and abroad, there is still no mature theory and method used for the long-term forecast of natural precipitation at present. In the present paper the disadvantages of grey GM (1, 1) and Markov chain are ana- lyzed, and Grey-Markov forecast theory about flood is put forward and then the modifying model is developed by making prediction of Chaohu Lake basin. Hydrological law was conducted based on the theoretical forecasts by grey system GM (1, 1) forecast model with improved Markov chain. The above method contained Stat-analysis, embodying scientific approach, precise forecast and its reliable results.
基金Supported by the National Basic Research Program of China (973 Program)(No. 2008CB418002)the National Major Programs of Water Body Pollution Control and Remediation (Nos. 2009ZX07106-001, 2009ZX07104-005)the National Natural Science Foundation of China (No. 30830025)
文摘Cyanobacterial blooms occur frequently in lakes due to eutrophication. Although a number of models have been proposed to forecast algal blooms, a good and applicable method is still lacking. This study explored a simple and effective mathematical-ecological model to evaluate the growth status and predict the population dynamics of Microcystis blooms. In this study, phytoplankton were collected and identified from 8 sampling sites in Chaohu Lake every month from July to October, 2010. The niche breadth and niche overlap of common species were calculated using standard equations, and the potential relative growth rates of Microcystis were calculated as a weighted-value of niche overlap. In July, the potential relative growth rate was 2.79 (a.u., arbitrary units) but then rapidly declined in the following months to -3.99 a.u. in September. A significant correlation (R=0.998, P<0.01) was found in the model between the net-increase in biomass of Microcystis in the field and the predicted values calculated by the niche model, we concluded that the niche model is suitable for forecasting the dynamics of Microcystis blooms. Redundancy analysis indicated that decreases in water temperature, dissolved oxygen and total dissolved phosphorus might be major factors underlying bloom decline. Based on the theory of community succession being caused by resource competition, the growth and decline of blooms can be predicted from a community structure. This may provide a basis for early warning and control of algal blooms.