We describe two new species of Sellaphora from Lake Fuxian, Ytmnan Plateau, China. Based on both light and scanning electron microscopy, these species are described as S. yunnanensis sp. nov. and S. sinensis sp. nov. ...We describe two new species of Sellaphora from Lake Fuxian, Ytmnan Plateau, China. Based on both light and scanning electron microscopy, these species are described as S. yunnanensis sp. nov. and S. sinensis sp. nov. The primary features of S. yunnanens＆ are： elliptical to linear-elliptical valves with broadly rounded ends, straight filiform raphe, almost straight central endings and small, slightly expanding central pores, small central area, symmetrical or slightly asymmetrical central nodule. The primary features of S. sinensis are： elliptical valves, obtusely rounded ends, similar raphe and axial area, transapically less expanded central area, larger, elliptical central nodule. We compare these species to those of a similar shape and morphology.展开更多
Lake Fuxian is the largest deep freshwater lake in China. Although its average water quality meets Class I of the China National Water Quality Standard （CNWQS）, i.e., GB3838-2002, monitoring data indicate that the w...Lake Fuxian is the largest deep freshwater lake in China. Although its average water quality meets Class I of the China National Water Quality Standard （CNWQS）, i.e., GB3838-2002, monitoring data indicate that the water quality approaches the Class II threshold in some areas. Thus it is urgent to reduce the watershed load through the total maximum daily load （TMDL） program. A three-dimensional hydrodynamic and water quality model was developed for Lake Fuxian, simulating flow circulation and pollutant fate and transport. The model development process consists of several steps, including grid generation, initial and boundary condition configurations, and model calibration processes. The model accurately reproduced the observed water surface elevation, spatiotemporal variations in temperature, and total nitrogen （TN）, total phosphorus （TP）, and chemical oxygen demand （COD） concentrations, suggesting a reasonable numerical representation of the prototype system for further TMDL analyses. The TMDL was calculated using two interpretations of the water quality standards for Class I of the CNWQS based on the maximum instantaneous surface and annual average surface water concentrations. Analysis of the first scenario indicated that the TN, TP and COD loads should be reduced by 66%, 68% and 57%, respectively. Water quality was the highest priority; however, local economic development and cost feasibility for load reduction can pose significant issues. In the second interpretation, the model results showed that, under the existing conditions, the average water quality meets the Class I standard and therefore load reduction is unnecessary. Future studies are needed to conduct risk and cost assessments for realistic decision-making.展开更多
By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were ...By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were respectively calculated.The tree species structure and the coverage degree of every kind of forest vegetation were investigated,and the characteristics of forest vegetation were analyzed.The results showed that the soil conservation amount of forest in Fuxian Lake basin was 137.50×106 t/a,and the soil conservation value was 622.30×106 yuan/a.Moreover,the water source conservation value was 506.84×106 yuan/a.展开更多
Lake Fuxian is a large, deep, and oligotrophic freshwater lake. In recent sediment of this lake, a series of branched and cyclic alkanes, including branched alkanes with one or two quaternary carbon atoms(C2ncompounds...Lake Fuxian is a large, deep, and oligotrophic freshwater lake. In recent sediment of this lake, a series of branched and cyclic alkanes, including branched alkanes with one or two quaternary carbon atoms(C2ncompounds),alkylcycloheptane, and alkylcyclohexane, were detected in high abundance. For each homolog of long-chain branched/cyclic alkanes, molecules with only an odd or even carbon number were present in the sediment. The abundance variation of each compound homolog corresponded to those of other compound homolog in the section, indicating the same origin of these compounds. The concentrations of long-chain branched/cyclic alkanes in the sediment profile exhibited variations similar to those of phytoplankton biomarkers,such as 3-methyl-alkanes, short-chain odd carbon n-alkanes,hopene, polyunsaturated fatty acids, phytol, sterols, and long-chain alkyl diols, but slightly different from those of long-chain odd carbon n-alkanes, which are ubiquitous biomarkers for higher plants. Therefore, the C2ncompounds and long-chain cyclic alkanes in the lake sediment were most likely produced by algae and bacteria in the water, primarily,by the heterotrophic bacteria in the moderately oxygenated waters, which flourishing might be the results of specific water environments in Lake Fuxian.展开更多
This paper has advanced a new method for determining historical earthquakes. Its object of study is lake sediments. The research method is environmental magnetism represented by susceptibility. The purpose is extracti...This paper has advanced a new method for determining historical earthquakes. Its object of study is lake sediments. The research method is environmental magnetism represented by susceptibility. The purpose is extracting historical earthquake informations from lake sediments to explore the correlation between the turbidity current sediments initiated by the earthquakes and historical earthquakes round Fuxian Lake.展开更多
[ Objective] The study aimed at discussing the purification effect of constructed wetlands for treating river water flowing from phosphate mine areas into Fuxian Lake. [Method] The running parameters of the constructe...[ Objective] The study aimed at discussing the purification effect of constructed wetlands for treating river water flowing from phosphate mine areas into Fuxian Lake. [Method] The running parameters of the constructed wetlands were investigated for one year, and the purification effect of the constructed wetlands for treating the sewage from phosphate mine areas was analyzed. [Result] With the aid of the constructed wet- land, the average removal rates of total nitrogen （TN）, total phosphorus （TP） and CODcr were 52%, 32% and 54%, and the removal effects were best when the designed hydraulic load was 0.67 m3/（ m2 · d）. Running stably for six years, the constructed wetlands had advantages of no power, low resistance and high removal rate. [ Conclusion] The constructed wetlands reduced the load of pollutants from phosphate mine areas into Fuxian Lake effectivelv, which Dlaved important roles in the Drotection of water aualitv of Fuxian Lake.展开更多
抚仙湖位于云南省玉溪市,流域生态资源丰富,但存在潜在环境风险。地理信息系统(Geographic Information System,GIS)具有强大的空间分析能力,常用于分析流域生态敏感性。为了保护抚仙湖,有必要建立评价因子指标体系,采用ArcGIS软件分析...抚仙湖位于云南省玉溪市,流域生态资源丰富,但存在潜在环境风险。地理信息系统(Geographic Information System,GIS)具有强大的空间分析能力,常用于分析流域生态敏感性。为了保护抚仙湖,有必要建立评价因子指标体系,采用ArcGIS软件分析抚仙湖流域生态敏感性,得到生态敏感性分区的面积比例,确定抚仙湖流域的生态保护区域。分析结果显示,极敏感区占流域面积的26.79%,属于重点保护区;高敏感区占比仅为2.01%,应限制人类活动对该区域的干扰;中敏感区占比为13.26%,开发前应专门进行可行性论证;低敏感区占比为27.48%,可进行适度开发;不敏感区占比为30.46%,可进行多用途开发。展开更多
基金Supported by the National Basic Research Program (973 Program) (No.2010CB833404)the Knowledge Innovation Program of the Chinese Academy of Sciences (Nos. KZCX2-YW-319 and KZCX1-YW-14)the National Natural Science Foundation of China (No. 40972114)
文摘We describe two new species of Sellaphora from Lake Fuxian, Ytmnan Plateau, China. Based on both light and scanning electron microscopy, these species are described as S. yunnanensis sp. nov. and S. sinensis sp. nov. The primary features of S. yunnanens＆ are： elliptical to linear-elliptical valves with broadly rounded ends, straight filiform raphe, almost straight central endings and small, slightly expanding central pores, small central area, symmetrical or slightly asymmetrical central nodule. The primary features of S. sinensis are： elliptical valves, obtusely rounded ends, similar raphe and axial area, transapically less expanded central area, larger, elliptical central nodule. We compare these species to those of a similar shape and morphology.
基金supported by the National Natural Science Foundation of China (No. 41101180)the China National Water Pollution Control Program (No.2010ZX07102-006)
文摘Lake Fuxian is the largest deep freshwater lake in China. Although its average water quality meets Class I of the China National Water Quality Standard （CNWQS）, i.e., GB3838-2002, monitoring data indicate that the water quality approaches the Class II threshold in some areas. Thus it is urgent to reduce the watershed load through the total maximum daily load （TMDL） program. A three-dimensional hydrodynamic and water quality model was developed for Lake Fuxian, simulating flow circulation and pollutant fate and transport. The model development process consists of several steps, including grid generation, initial and boundary condition configurations, and model calibration processes. The model accurately reproduced the observed water surface elevation, spatiotemporal variations in temperature, and total nitrogen （TN）, total phosphorus （TP）, and chemical oxygen demand （COD） concentrations, suggesting a reasonable numerical representation of the prototype system for further TMDL analyses. The TMDL was calculated using two interpretations of the water quality standards for Class I of the CNWQS based on the maximum instantaneous surface and annual average surface water concentrations. Analysis of the first scenario indicated that the TN, TP and COD loads should be reduced by 66%, 68% and 57%, respectively. Water quality was the highest priority; however, local economic development and cost feasibility for load reduction can pose significant issues. In the second interpretation, the model results showed that, under the existing conditions, the average water quality meets the Class I standard and therefore load reduction is unnecessary. Future studies are needed to conduct risk and cost assessments for realistic decision-making.
基金Supported by Yuxi Forest Resource Planning Design Investigation Project in Yunnan Province
文摘By using French SPOT5 satellite remote sensing image to contrast on the spot,the forest vegetation in Fuxian Lake basin was categorized into 23 forest types,6 vegetation subtypes,5 vegetation types,and the areas were respectively calculated.The tree species structure and the coverage degree of every kind of forest vegetation were investigated,and the characteristics of forest vegetation were analyzed.The results showed that the soil conservation amount of forest in Fuxian Lake basin was 137.50×106 t/a,and the soil conservation value was 622.30×106 yuan/a.Moreover,the water source conservation value was 506.84×106 yuan/a.
基金supported by the National Natural Science Foundation of China(U1033602 and 31100341)‘‘135’ ’NIGLAS Key Program(NIGLAS2012135007)President Fund Program of Chinese Academy of Sciences(NIGLAS2012QD11)
文摘Lake Fuxian is a large, deep, and oligotrophic freshwater lake. In recent sediment of this lake, a series of branched and cyclic alkanes, including branched alkanes with one or two quaternary carbon atoms(C2ncompounds),alkylcycloheptane, and alkylcyclohexane, were detected in high abundance. For each homolog of long-chain branched/cyclic alkanes, molecules with only an odd or even carbon number were present in the sediment. The abundance variation of each compound homolog corresponded to those of other compound homolog in the section, indicating the same origin of these compounds. The concentrations of long-chain branched/cyclic alkanes in the sediment profile exhibited variations similar to those of phytoplankton biomarkers,such as 3-methyl-alkanes, short-chain odd carbon n-alkanes,hopene, polyunsaturated fatty acids, phytol, sterols, and long-chain alkyl diols, but slightly different from those of long-chain odd carbon n-alkanes, which are ubiquitous biomarkers for higher plants. Therefore, the C2ncompounds and long-chain cyclic alkanes in the lake sediment were most likely produced by algae and bacteria in the water, primarily,by the heterotrophic bacteria in the moderately oxygenated waters, which flourishing might be the results of specific water environments in Lake Fuxian.
文摘This paper has advanced a new method for determining historical earthquakes. Its object of study is lake sediments. The research method is environmental magnetism represented by susceptibility. The purpose is extracting historical earthquake informations from lake sediments to explore the correlation between the turbidity current sediments initiated by the earthquakes and historical earthquakes round Fuxian Lake.
基金Supported by Key Project of Social Development Basic Research of Yunnan Provincial Science and Technology Department(2009cc025)
文摘[ Objective] The study aimed at discussing the purification effect of constructed wetlands for treating river water flowing from phosphate mine areas into Fuxian Lake. [Method] The running parameters of the constructed wetlands were investigated for one year, and the purification effect of the constructed wetlands for treating the sewage from phosphate mine areas was analyzed. [Result] With the aid of the constructed wet- land, the average removal rates of total nitrogen （TN）, total phosphorus （TP） and CODcr were 52%, 32% and 54%, and the removal effects were best when the designed hydraulic load was 0.67 m3/（ m2 · d）. Running stably for six years, the constructed wetlands had advantages of no power, low resistance and high removal rate. [ Conclusion] The constructed wetlands reduced the load of pollutants from phosphate mine areas into Fuxian Lake effectivelv, which Dlaved important roles in the Drotection of water aualitv of Fuxian Lake.
文摘抚仙湖位于云南省玉溪市,流域生态资源丰富,但存在潜在环境风险。地理信息系统(Geographic Information System,GIS)具有强大的空间分析能力,常用于分析流域生态敏感性。为了保护抚仙湖,有必要建立评价因子指标体系,采用ArcGIS软件分析抚仙湖流域生态敏感性,得到生态敏感性分区的面积比例,确定抚仙湖流域的生态保护区域。分析结果显示,极敏感区占流域面积的26.79%,属于重点保护区;高敏感区占比仅为2.01%,应限制人类活动对该区域的干扰;中敏感区占比为13.26%,开发前应专门进行可行性论证;低敏感区占比为27.48%,可进行适度开发;不敏感区占比为30.46%,可进行多用途开发。
