On the basis of introducing the status quo of land use in Luan County,the existing problems in the process of land use are analyzed as follows.First,the farmland is the majority,the area of garden land and forests is ...On the basis of introducing the status quo of land use in Luan County,the existing problems in the process of land use are analyzed as follows.First,the farmland is the majority,the area of garden land and forests is small and the farmland quality degenerates;second,the scale of construction use land is large,but the intensification level is low;third,reserve resources are scanty and the pressure of protecting farmland mounts.This paper discusses the orientation of Luan County in provincial and municipal land use strategy and geographical conditions of Luan County,analyzes the future development status of Luan County,and proposes that we should take guaranteeing land use strategy realization of Hebei Province and Tangshan City as important condition of land use strategy selection of Luan County.It points out that we should implement land use strategy of Luan County from the following aspects:first,strictly protect farmland,especially the basic farmland;second,focus on economic development and adopt intensive and high-efficiency land use pattern;third,pay equal attention to ecological protection and construction,and adopt many means to improve ecological environment.展开更多
Luan River is the main water source in Beijing-Tianjin-Hebei region,northern China,where the groundwater system is vulnerable and pollution issue is serious.It is significant for regional groundwater resources protect...Luan River is the main water source in Beijing-Tianjin-Hebei region,northern China,where the groundwater system is vulnerable and pollution issue is serious.It is significant for regional groundwater resources protection to identify the hydrogeochemistry evolution and affecting factors along flow direction occurred in the upper reaches,especially the surface water-groundwater(SWGW)conversion relationship.In this study,recharge,conversion and geochemistry evolution of SW and GW were elucidated based on physical-hydrochemical indicators and stable isotopes in 36 GW samples and 20 SW samples,which were collected in July 2019 and July 2020.The factor analysis was further utilized to determine the main factors responsible for regional hydrogeochemical evolution.Results indicate that GW recharged SW in plateau area,and SW and GW recharged each other in typical Alpine valley area.The hydrochemical types are HCO3-Ca·Mg and HCO3-Ca,and the hydrochemical evolution is dominated by weathering of silicate and carbonate minerals.The cation exchange adsorption has minor impact on groundwater hydrochemistry.The rise of SO42-and NO3-contents in groundwater is related to industrial and agricultural activities.The main controlling factors of SW hydrochemical components included recharge from groundwater,industrial and mining activities,explaining 90.04%of data variance.However,water-rock interaction,agricultural and domestic sewage are responsible for GW quality,accounting for 83.38%.展开更多
Concentrations of the heavy metals Cu, Ni, Pb, Zn, Cd, and Cr were examined in surface water and sediment from the Luan River inChina,. With a decline in Cu and Ni concentration found in surface water at downstream st...Concentrations of the heavy metals Cu, Ni, Pb, Zn, Cd, and Cr were examined in surface water and sediment from the Luan River inChina,. With a decline in Cu and Ni concentration found in surface water at downstream stations. This finding suggests that water currents are a major explanatory factor in heavy metal contamination. The abundance of Cr, Pb, and Cd observed in the middle reaches of the river indicates heavy metal contamination in local areas, although there was an obvious decrease in concentrations in the water downstream of the Daheiting Reservoir. The significant rising trend in Cu, Pb, and Ni seen the sediment farther away from the river also suggests that anthropogenic activities contribute to heavy metal pollution Sediments were therefore used as environmental indicators, with sediment assessment was conducted using the geo-accumulation index （Igeo） and the potential ecological risk index （R/）. The Igeo values revealed that Cd （3.13） and Cr （2.39） had accumulated significantly in the Luan River. The R/values for most （89%） of the sampling stations were higher than 300, suggesting that sediment from the Luan River poses a severe ecological risk, with the potential ecological risks downstream higher than that in the upper and middle streams. Good correlations among Pb/Ni, Pb/Cd, Cu/Pb, and Cu/Cd in the water and Cr/Ni in the sediment were observed. Cluster analysis suggested that Cd may have various origins, being derived from anthropogenic sources.展开更多
Amomg the BO known species of the algal family Prasiolaceae （Prasiolales, Chlorophyta}, nine marine species have been found in marine environments but none in China seas. We reported here two new species Prasiola fan...Amomg the BO known species of the algal family Prasiolaceae （Prasiolales, Chlorophyta}, nine marine species have been found in marine environments but none in China seas. We reported here two new species Prasiola fangchengensis Luan et Ding sp. nov. and Prasiola volcanica Luan et Ding sp. nov. from subtropical coastal water of southern China.展开更多
文摘On the basis of introducing the status quo of land use in Luan County,the existing problems in the process of land use are analyzed as follows.First,the farmland is the majority,the area of garden land and forests is small and the farmland quality degenerates;second,the scale of construction use land is large,but the intensification level is low;third,reserve resources are scanty and the pressure of protecting farmland mounts.This paper discusses the orientation of Luan County in provincial and municipal land use strategy and geographical conditions of Luan County,analyzes the future development status of Luan County,and proposes that we should take guaranteeing land use strategy realization of Hebei Province and Tangshan City as important condition of land use strategy selection of Luan County.It points out that we should implement land use strategy of Luan County from the following aspects:first,strictly protect farmland,especially the basic farmland;second,focus on economic development and adopt intensive and high-efficiency land use pattern;third,pay equal attention to ecological protection and construction,and adopt many means to improve ecological environment.
基金funded by the Ecological Civilization Demonstration Area Comprehensive Geological Survey Project“Hydrogeological Survey of Chengde Area”(No.DD20200522)the National Natural Science Foundation of China(Nos.41521001 and 42177078)the“111”Program of China(No.B18049).
文摘Luan River is the main water source in Beijing-Tianjin-Hebei region,northern China,where the groundwater system is vulnerable and pollution issue is serious.It is significant for regional groundwater resources protection to identify the hydrogeochemistry evolution and affecting factors along flow direction occurred in the upper reaches,especially the surface water-groundwater(SWGW)conversion relationship.In this study,recharge,conversion and geochemistry evolution of SW and GW were elucidated based on physical-hydrochemical indicators and stable isotopes in 36 GW samples and 20 SW samples,which were collected in July 2019 and July 2020.The factor analysis was further utilized to determine the main factors responsible for regional hydrogeochemical evolution.Results indicate that GW recharged SW in plateau area,and SW and GW recharged each other in typical Alpine valley area.The hydrochemical types are HCO3-Ca·Mg and HCO3-Ca,and the hydrochemical evolution is dominated by weathering of silicate and carbonate minerals.The cation exchange adsorption has minor impact on groundwater hydrochemistry.The rise of SO42-and NO3-contents in groundwater is related to industrial and agricultural activities.The main controlling factors of SW hydrochemical components included recharge from groundwater,industrial and mining activities,explaining 90.04%of data variance.However,water-rock interaction,agricultural and domestic sewage are responsible for GW quality,accounting for 83.38%.
基金Acknowledgements This study was financially supported by the National Natural Science Foundation of China （Grant No. 40925003）, the National Major Scientific and Technological Specific Projects of China （2012ZX07501002002）.
文摘Concentrations of the heavy metals Cu, Ni, Pb, Zn, Cd, and Cr were examined in surface water and sediment from the Luan River inChina,. With a decline in Cu and Ni concentration found in surface water at downstream stations. This finding suggests that water currents are a major explanatory factor in heavy metal contamination. The abundance of Cr, Pb, and Cd observed in the middle reaches of the river indicates heavy metal contamination in local areas, although there was an obvious decrease in concentrations in the water downstream of the Daheiting Reservoir. The significant rising trend in Cu, Pb, and Ni seen the sediment farther away from the river also suggests that anthropogenic activities contribute to heavy metal pollution Sediments were therefore used as environmental indicators, with sediment assessment was conducted using the geo-accumulation index （Igeo） and the potential ecological risk index （R/）. The Igeo values revealed that Cd （3.13） and Cr （2.39） had accumulated significantly in the Luan River. The R/values for most （89%） of the sampling stations were higher than 300, suggesting that sediment from the Luan River poses a severe ecological risk, with the potential ecological risks downstream higher than that in the upper and middle streams. Good correlations among Pb/Ni, Pb/Cd, Cu/Pb, and Cu/Cd in the water and Cr/Ni in the sediment were observed. Cluster analysis suggested that Cd may have various origins, being derived from anthropogenic sources.
基金The general and major projects of the National Natural Science Foundation of China (NSFC) under contract No.40876081The general and major projects of the National Natural Science Foundation of China (NSFC) under contract No.30570125The general and major projects of the National Natural Science Foundation of China (NSFC) under contract No.30499340 (partly) respectively
文摘Amomg the BO known species of the algal family Prasiolaceae （Prasiolales, Chlorophyta}, nine marine species have been found in marine environments but none in China seas. We reported here two new species Prasiola fangchengensis Luan et Ding sp. nov. and Prasiola volcanica Luan et Ding sp. nov. from subtropical coastal water of southern China.
