Water samples were collected in 120 stations in the Bohai Sea of China to analyze the distribution of dissolved nutrients and assess the degree of eutrophication in August 2002. The result shows that the average conce...Water samples were collected in 120 stations in the Bohai Sea of China to analyze the distribution of dissolved nutrients and assess the degree of eutrophication in August 2002. The result shows that the average concentration of DIN increased and the PO4-P concentration sharply decreased compared to the previous data of corresponding period. The high concentrations of DIN and PO4-P occurred in coastal waters, especially in the bays and some river estuaries, while the high concentrations of SiO3-Si in the surface and middle depth occurred in the central area of the Bohai Sea. The average ratio of DIN/PO4-P was much higher than the Redfield Ratio （16：1）. Apparently, PO4-P was one of the limiting nutrient for phytoplankton growing in the sea. The average concentrations of DON and DOP were higher than their inorganic forms. The results of eutrophication assessment show that 22.1% of all stations were classified as violating the concentration levels of the National Seawater Quality Standard （GB 3097-1997） for DIN and only 3.9% for PO4-R The average eutrophication index in the overall area was 0.21±0.22 and the high values occurred in Bohai Bay, Liaodong Bay and near the Yellow River estuary. This means that the state of eutrophication was generally mesotrophic in the Bohai Sea, but relatively worse in the bays, especially some river estuaries.展开更多
Water shortage is a major issue in northern China. With the transfer of China＇s economic center from south to north, Circum-Bohai Economic Circle has gradually formed and developed as the third pole of China＇s econo...Water shortage is a major issue in northern China. With the transfer of China＇s economic center from south to north, Circum-Bohai Economic Circle has gradually formed and developed as the third pole of China＇s economy after Yangtze River Delta and Pearl River Delta, the problem of water has inevitably become more and more serious. South-to-North Water Diversion and Sea Water Desalination are helpful to solve this dilemma, but some difficulties appeared during the course of the two projects. By contrast, sea ice desalination can be considered as a third way to alleviate freshwater crisis in Bohai Rim. Firstly, the amount of sea ice in Bohai Sea is as much as 1.27 billion m3 even in normal years. Then the salinity of sea ice is only 1/4 to 1/7 as that of sea water. And furthermore, desalinized water of sea ice can meet national water quality standard for drinking. Purposely use the abundant sea ice resources as water source for industry, agriculture and living is very likely to open a new path for the solution of freshwater shortage, which can promote rapid and healthy development of Circum-Bohai Economic Circle.展开更多
基金Supported by the National Natural Science Foundation of China (No. 40136020)Key International Technology Cooperation Plan (No. 2004DFA03600)the National Basic Research Program of China (973 Program, No. 2005CB422305)
文摘Water samples were collected in 120 stations in the Bohai Sea of China to analyze the distribution of dissolved nutrients and assess the degree of eutrophication in August 2002. The result shows that the average concentration of DIN increased and the PO4-P concentration sharply decreased compared to the previous data of corresponding period. The high concentrations of DIN and PO4-P occurred in coastal waters, especially in the bays and some river estuaries, while the high concentrations of SiO3-Si in the surface and middle depth occurred in the central area of the Bohai Sea. The average ratio of DIN/PO4-P was much higher than the Redfield Ratio （16：1）. Apparently, PO4-P was one of the limiting nutrient for phytoplankton growing in the sea. The average concentrations of DON and DOP were higher than their inorganic forms. The results of eutrophication assessment show that 22.1% of all stations were classified as violating the concentration levels of the National Seawater Quality Standard （GB 3097-1997） for DIN and only 3.9% for PO4-R The average eutrophication index in the overall area was 0.21±0.22 and the high values occurred in Bohai Bay, Liaodong Bay and near the Yellow River estuary. This means that the state of eutrophication was generally mesotrophic in the Bohai Sea, but relatively worse in the bays, especially some river estuaries.
文摘Water shortage is a major issue in northern China. With the transfer of China＇s economic center from south to north, Circum-Bohai Economic Circle has gradually formed and developed as the third pole of China＇s economy after Yangtze River Delta and Pearl River Delta, the problem of water has inevitably become more and more serious. South-to-North Water Diversion and Sea Water Desalination are helpful to solve this dilemma, but some difficulties appeared during the course of the two projects. By contrast, sea ice desalination can be considered as a third way to alleviate freshwater crisis in Bohai Rim. Firstly, the amount of sea ice in Bohai Sea is as much as 1.27 billion m3 even in normal years. Then the salinity of sea ice is only 1/4 to 1/7 as that of sea water. And furthermore, desalinized water of sea ice can meet national water quality standard for drinking. Purposely use the abundant sea ice resources as water source for industry, agriculture and living is very likely to open a new path for the solution of freshwater shortage, which can promote rapid and healthy development of Circum-Bohai Economic Circle.
