Honghu Lake,located in the southeast of Hubei Province,China,has suffered a severe disturbance during the past few decades.To restore the ecosystem,the Honghu Lake Wetland Protection and Restoration Demonstration Proj...Honghu Lake,located in the southeast of Hubei Province,China,has suffered a severe disturbance during the past few decades.To restore the ecosystem,the Honghu Lake Wetland Protection and Restoration Demonstration Project(HLWPRDP) has been implemented since 2004.A back propagation(BP) artificial neural network(ANN) approach was applied to evaluatinig the ecosystem health of the Honghu Lake wetland.And the effectiveness of the HLWPRDP was also assessed by comparing the ecosystem health before and after the project.Particularly,12 ecosystem health indices were used as evaluation parameters to establish a set of three-layer BP ANNs.The output is one layer of ecosystem health index.After training and testing the BP ANNs,an optimal model of BP ANNs was selected to assess the ecosystem health of the Honghu Lake wetland.The result indicates that four stages can be identified based on the change of the ecosystem health from 1990 to 2008 and the ecosystem health index ranges from morbidity before the implementation of HLWPRDP(in 2002) to middle health after the implementation of the HLWPRDP(in 2005).It demonstrates that the HLWPRDP is effective and the BP ANN could be used as a tool for the assessment of ecosystem health.展开更多
Vertical profiles of the total organic carbon （TOC）, total nitrogen （TN）, phosphorus, susceptibilities, elements and partical size were analyzed in a short ^137Cs-dated sediment core collected from Honghu Lake, Ch...Vertical profiles of the total organic carbon （TOC）, total nitrogen （TN）, phosphorus, susceptibilities, elements and partical size were analyzed in a short ^137Cs-dated sediment core collected from Honghu Lake, China. The average sedimentation rate was 1.55 mm/a. The results indicated that trophic status of Honghu Lake in the historical period had experienced three stages. Before 1840 the lake was characterized with lower productivity, TOC was less than 9.92 g/kg; TN was 0.902 to 1.24 g/kg. During about 1840-1950, population increased quickly, there was an obvious change in TOC with an average of 13.0 g/kg. Since 1950, human impacts have accelerated the lake eutrophication and nutrients enriched in the sediment with TOC of 21.7 to 93.1 g/kg, TN of 1.77 to 8.78 g/kg. The heavy metal concentration profiles presented similar distribution trends except Pb .and Mn. The results from elements analyses indicated that Honghu Lake had not been polluted by heavy metals except lead.展开更多
To assess the value of air regulation in the Honghu Lake Wetland,a quantitative study was conducted based on existing literatures. Results showed that the total service value of air regulation in the Honghu Lake Wetla...To assess the value of air regulation in the Honghu Lake Wetland,a quantitative study was conducted based on existing literatures. Results showed that the total service value of air regulation in the Honghu Lake Wetland was 254. 52 million yuan/a,which was 11. 6 times of that by previous studies. The net value of fixed greenhouse gases via wetland plants( including carbon emission value from methane emission conversion into carbon dioxide greenhouse gas effect) was 58. 50 million yuan/a,the data indicated that this lake wetland was a strong carbon sink. The value of oxygen released by the wetland ecosystem was 176. 51 million yuan/a,and the value of regulating air humidity and temperature was 19. 51 million yuan/a. The net value of greenhouse gases fixed by the Honghu Lake Wetland vegetation,the value of released oxygen,and the value of lifting air humidity and temperature regulation accounted for 22. 98%,69. 35%,and 7. 70% of the total value of the air regulation services,respectively.展开更多
Five trace elements including Zn, Cu, Cd, Cr and As were investigated in surface water from ten typical sampling sites in Honghu Lake. The consequence indicated that all of the detected trace element levels were withi...Five trace elements including Zn, Cu, Cd, Cr and As were investigated in surface water from ten typical sampling sites in Honghu Lake. The consequence indicated that all of the detected trace element levels were within the allowed standard of China’s safe water guideline. The hazard quotients （HQ） and the hazard index （HI） value levels of all the five heavy metals in all sampling sites did not exceed the acceptable risk limits of non-carcinogenic value through the selected assessment method. Pearson’s correlation analysis and principal component analysis （PCA） indicated that Zn and Cu mainly originated from the natural alluviation and non-point agricultural sources, whereas Cr and As were mainly derived from industrial effluents. Moreover, Cd mainly originated from both non-point agricultural and industrial pollution sources. In addition, cluster analysis （CA） implied that cluster 1 （including S3, S5, S6 and S10） was considered the set of high pollution sites and cluster 2 （including S4 and S9） was identified as the set of moderate pollution sites.展开更多
The levels of 13 organochlorine pesticides （OCPs） in sediments of Honghu Lake were investigated in order to evaluate their potential pollution and risk. A total of 30 sediment samples from 15 sampling locations were...The levels of 13 organochlorine pesticides （OCPs） in sediments of Honghu Lake were investigated in order to evaluate their potential pollution and risk. A total of 30 sediment samples from 15 sampling locations were collected in the lake during July, 2005. The total concentrations in top-sediment samples and sub-sediment samples ranged from 3.52 ng/g to 69.71 ng/g and 0.49 ng/g to 97.37 ng/g, respectively. The HCH isomers, DDT congeners, aldrin, trans-chlordane, cis-chlordane, heptachlor and endrin-ketone were significant in these samples. The concentrations of OCPs in the lakeshore sediments were higher than those sampled across the lake. Distribution of HCHs, DDTs and other OCPs were different, indicating their various contamination sources. Composition analysis in sediments indicated recent usage or discharge of lindane, dicofol into the lake.展开更多
Honghu Lake, which is listed in the Ramsar Convention, was found to be contaminated with elevated nutrients to a certain extent.This study investigated the seasonal variation of major nutrients and probabilistic eutro...Honghu Lake, which is listed in the Ramsar Convention, was found to be contaminated with elevated nutrients to a certain extent.This study investigated the seasonal variation of major nutrients and probabilistic eutrophic state in surface water from Honghu Lake. Average concentrations of total nitrogen(TN), total phosphorus(TP), chlorophyll-a(Chl-a), chemical oxygen demand(COD_(Mn)) and transparency(SD) in summer and winter generally exceeded Grade III of the Chinese environmental quality standards for surface water(GB 3838-2002), with the exception of COD_(Mn)in winter. Mean concentrations of Chl-a and COD_(Mn) in summer were higher than that in winter, while mean concentrations of TN, TP and SD were slightly higher in winter. The improved probabilistic comprehensive trophic level index(PTLI) method based on stochastic-fuzzy theory was established to evaluate the eutrophic state in Honghu Lake. Compared with the Monte-Carlo sampling method, the Latin Hypercube sampling(LH-TFN) method was selected for the evaluation simulation due to its efficiency and stability. Evaluation results indicated that mean PTLI in summer(69.70) and winter(61.96) were both subordinated to Grade IV(Medium eutrophication). The corresponding reliability of eutrophication level subordinating to Grade IV in summer was of relatively low reliability(51.27%),which might mislead decision makers to some extent and suggest recheck. The probabilistic eutrophication level in summer developed with a trend from medium to severe eutrophication. Sensitivity analysis illustrated that COD_(Mn)and Chl-a were the priority pollutants in summer, with the contributions to PTLI of 43.3% and 22.5% respectively. Chl-a was the priority pollutant in winter, with the contribution to PTLI up to 51.3%.展开更多
Nutrients transported from catchments are one of the most important sources for lake eutrophication. In this study, the Honghu Lake Basin, located at the middle reaches of the Yangtze River, was chosen as the study ar...Nutrients transported from catchments are one of the most important sources for lake eutrophication. In this study, the Honghu Lake Basin, located at the middle reaches of the Yangtze River, was chosen as the study area, and the watershed hydrological distribution model SWAT (Soil Water Assessment Tool) was applied to evaluate the trajectory of watershed nutrient transportation over time. Based on the analysis of driving factors, three experiments corresponding to natural, traditional and modern agriculture processes respectively were designed to evaluate the changes of nutrient inputs from catchments under the three environments. The simulation results showed that there were variations in nutrient production and changes in the range and rate. For three periods of the experiments, TN concentrations have changed as 0.12→0.31→1.15 mg/L, and production as 420→1650→6522 T/a; while TP concentrations changed as 0.018→0.057→0.117 mg/L, and production as 78→303→665 T/a. The nutrient transportation experienced slowly long-term increases during 1840―1950, then showed a relatively rapid increase during the period of 1950―1980s and the period from 1980 to early 1990s, with increasing rate of 1.4% and 2.4% respectively. And from the later 1990s to now, an obviously increasing trend with 15% increasing rate occurred. The effect from human activities on the watershed nutrient transportation increased rapidly, and had become a dominant factor in changes of the nutrient transportation.展开更多
基金Under the auspices of National Natural Science Foundation of China (No 40871251)Knowledge Innovation Programs of Chinese Academy of Sciences (No KZCX2-YW-141)
文摘Honghu Lake,located in the southeast of Hubei Province,China,has suffered a severe disturbance during the past few decades.To restore the ecosystem,the Honghu Lake Wetland Protection and Restoration Demonstration Project(HLWPRDP) has been implemented since 2004.A back propagation(BP) artificial neural network(ANN) approach was applied to evaluatinig the ecosystem health of the Honghu Lake wetland.And the effectiveness of the HLWPRDP was also assessed by comparing the ecosystem health before and after the project.Particularly,12 ecosystem health indices were used as evaluation parameters to establish a set of three-layer BP ANNs.The output is one layer of ecosystem health index.After training and testing the BP ANNs,an optimal model of BP ANNs was selected to assess the ecosystem health of the Honghu Lake wetland.The result indicates that four stages can be identified based on the change of the ecosystem health from 1990 to 2008 and the ecosystem health index ranges from morbidity before the implementation of HLWPRDP(in 2002) to middle health after the implementation of the HLWPRDP(in 2005).It demonstrates that the HLWPRDP is effective and the BP ANN could be used as a tool for the assessment of ecosystem health.
文摘Vertical profiles of the total organic carbon （TOC）, total nitrogen （TN）, phosphorus, susceptibilities, elements and partical size were analyzed in a short ^137Cs-dated sediment core collected from Honghu Lake, China. The average sedimentation rate was 1.55 mm/a. The results indicated that trophic status of Honghu Lake in the historical period had experienced three stages. Before 1840 the lake was characterized with lower productivity, TOC was less than 9.92 g/kg; TN was 0.902 to 1.24 g/kg. During about 1840-1950, population increased quickly, there was an obvious change in TOC with an average of 13.0 g/kg. Since 1950, human impacts have accelerated the lake eutrophication and nutrients enriched in the sediment with TOC of 21.7 to 93.1 g/kg, TN of 1.77 to 8.78 g/kg. The heavy metal concentration profiles presented similar distribution trends except Pb .and Mn. The results from elements analyses indicated that Honghu Lake had not been polluted by heavy metals except lead.
基金Supported by Project of Honghu Lake Wetland National Ecosystem Research Station,State Forestry Administration of the People’s Republic of China(2017-LYPT-DW-059)
文摘To assess the value of air regulation in the Honghu Lake Wetland,a quantitative study was conducted based on existing literatures. Results showed that the total service value of air regulation in the Honghu Lake Wetland was 254. 52 million yuan/a,which was 11. 6 times of that by previous studies. The net value of fixed greenhouse gases via wetland plants( including carbon emission value from methane emission conversion into carbon dioxide greenhouse gas effect) was 58. 50 million yuan/a,the data indicated that this lake wetland was a strong carbon sink. The value of oxygen released by the wetland ecosystem was 176. 51 million yuan/a,and the value of regulating air humidity and temperature was 19. 51 million yuan/a. The net value of greenhouse gases fixed by the Honghu Lake Wetland vegetation,the value of released oxygen,and the value of lifting air humidity and temperature regulation accounted for 22. 98%,69. 35%,and 7. 70% of the total value of the air regulation services,respectively.
基金Projects(51578222,51178172) supported by the National Natural Science Foundation of ChinaProjects(17Z017,17G025) supported by the Humanities and Social Science Project of Hubei Provincial Education Department,China+1 种基金Project(1718WT15) supported by the Hubei College Student Affairs Research Institute,ChinaProjects(2016J1410,2016J1411) supported by the Graduate Innovative Education Program of Zhongnan University of Economics and Law,China
文摘Five trace elements including Zn, Cu, Cd, Cr and As were investigated in surface water from ten typical sampling sites in Honghu Lake. The consequence indicated that all of the detected trace element levels were within the allowed standard of China’s safe water guideline. The hazard quotients （HQ） and the hazard index （HI） value levels of all the five heavy metals in all sampling sites did not exceed the acceptable risk limits of non-carcinogenic value through the selected assessment method. Pearson’s correlation analysis and principal component analysis （PCA） indicated that Zn and Cu mainly originated from the natural alluviation and non-point agricultural sources, whereas Cr and As were mainly derived from industrial effluents. Moreover, Cd mainly originated from both non-point agricultural and industrial pollution sources. In addition, cluster analysis （CA） implied that cluster 1 （including S3, S5, S6 and S10） was considered the set of high pollution sites and cluster 2 （including S4 and S9） was identified as the set of moderate pollution sites.
文摘The levels of 13 organochlorine pesticides （OCPs） in sediments of Honghu Lake were investigated in order to evaluate their potential pollution and risk. A total of 30 sediment samples from 15 sampling locations were collected in the lake during July, 2005. The total concentrations in top-sediment samples and sub-sediment samples ranged from 3.52 ng/g to 69.71 ng/g and 0.49 ng/g to 97.37 ng/g, respectively. The HCH isomers, DDT congeners, aldrin, trans-chlordane, cis-chlordane, heptachlor and endrin-ketone were significant in these samples. The concentrations of OCPs in the lakeshore sediments were higher than those sampled across the lake. Distribution of HCHs, DDTs and other OCPs were different, indicating their various contamination sources. Composition analysis in sediments indicated recent usage or discharge of lindane, dicofol into the lake.
基金supported by the Humanities and Social Sciences Foundation of Ministry of Education of China(Grant No.17YJCZH081)Natural Science Foundation of Hubei Province and the Science and Technology Research Project of Hubei Provincial Education Department(Grant No.B2017601)
文摘Honghu Lake, which is listed in the Ramsar Convention, was found to be contaminated with elevated nutrients to a certain extent.This study investigated the seasonal variation of major nutrients and probabilistic eutrophic state in surface water from Honghu Lake. Average concentrations of total nitrogen(TN), total phosphorus(TP), chlorophyll-a(Chl-a), chemical oxygen demand(COD_(Mn)) and transparency(SD) in summer and winter generally exceeded Grade III of the Chinese environmental quality standards for surface water(GB 3838-2002), with the exception of COD_(Mn)in winter. Mean concentrations of Chl-a and COD_(Mn) in summer were higher than that in winter, while mean concentrations of TN, TP and SD were slightly higher in winter. The improved probabilistic comprehensive trophic level index(PTLI) method based on stochastic-fuzzy theory was established to evaluate the eutrophic state in Honghu Lake. Compared with the Monte-Carlo sampling method, the Latin Hypercube sampling(LH-TFN) method was selected for the evaluation simulation due to its efficiency and stability. Evaluation results indicated that mean PTLI in summer(69.70) and winter(61.96) were both subordinated to Grade IV(Medium eutrophication). The corresponding reliability of eutrophication level subordinating to Grade IV in summer was of relatively low reliability(51.27%),which might mislead decision makers to some extent and suggest recheck. The probabilistic eutrophication level in summer developed with a trend from medium to severe eutrophication. Sensitivity analysis illustrated that COD_(Mn)and Chl-a were the priority pollutants in summer, with the contributions to PTLI of 43.3% and 22.5% respectively. Chl-a was the priority pollutant in winter, with the contribution to PTLI up to 51.3%.
基金the Major Special Program of National Science and Technology of China (Grant No. 2008ZX02002-001)
文摘Nutrients transported from catchments are one of the most important sources for lake eutrophication. In this study, the Honghu Lake Basin, located at the middle reaches of the Yangtze River, was chosen as the study area, and the watershed hydrological distribution model SWAT (Soil Water Assessment Tool) was applied to evaluate the trajectory of watershed nutrient transportation over time. Based on the analysis of driving factors, three experiments corresponding to natural, traditional and modern agriculture processes respectively were designed to evaluate the changes of nutrient inputs from catchments under the three environments. The simulation results showed that there were variations in nutrient production and changes in the range and rate. For three periods of the experiments, TN concentrations have changed as 0.12→0.31→1.15 mg/L, and production as 420→1650→6522 T/a; while TP concentrations changed as 0.018→0.057→0.117 mg/L, and production as 78→303→665 T/a. The nutrient transportation experienced slowly long-term increases during 1840―1950, then showed a relatively rapid increase during the period of 1950―1980s and the period from 1980 to early 1990s, with increasing rate of 1.4% and 2.4% respectively. And from the later 1990s to now, an obviously increasing trend with 15% increasing rate occurred. The effect from human activities on the watershed nutrient transportation increased rapidly, and had become a dominant factor in changes of the nutrient transportation.
