利用连云港海州湾2004年至2006年的水质监测资料,选取时间上完全同步的空间分辨率为500m的 MODIS Terra 1B 数据,对反射率的单波段因子和波段组合因子与可溶无机氮(DIN)质量浓度之间进行相关分析。从总体上看,单波段因子与 DIN 质量浓...利用连云港海州湾2004年至2006年的水质监测资料,选取时间上完全同步的空间分辨率为500m的 MODIS Terra 1B 数据,对反射率的单波段因子和波段组合因子与可溶无机氮(DIN)质量浓度之间进行相关分析。从总体上看,单波段因子与 DIN 质量浓度的相关性较低,但在含氮基团倍频和合频吸收带附近的波段(波段2、7)反射率与 DIN 质量浓度呈负相关,显示了含氮基团对水体光谱特征的影响;在波段组合因子中,因子 F_(11(3,4))和 F_(13(3,4))与 DIN 质量浓度呈显著正相关,用这两个因子建立 DIN 质量浓度的回归模型,R^2达到0.7以上,相对精度达70%左右,最终选择因子 F_(11(3,4))的线性模型反演该海域的 DIN质量浓度,其结果与实际情况非常吻合。展开更多
Systematic studies of the changes in dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphorus(DIP) and their effects on phytoplankton over the last 30 years in the Bohai Sea are presented.The amount of sew...Systematic studies of the changes in dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphorus(DIP) and their effects on phytoplankton over the last 30 years in the Bohai Sea are presented.The amount of sewage disposal,use of fertilizer and the Huanghe River runoff were found to have a significant influence on the DIN or DIP concentrations in the Bohai Sea over the last 30 years.Moreover,the changes in DIN and DIP resulted in changes in the limiting nutrients of phytoplankton in the Bohai Sea from nitrogen in the early 1980s to nitrogen-phosphorus in the late 1980s,and then to phosphorus after the 1990s.In addition,changes in nitrogen and phosphorus had a significant effect on the phytoplankton community structure.The half saturation constant(Ks) was used to evaluate the effect of nutrients on the phytoplankton community structure in the Bohai Sea over the last 30 years.Cell abundance percentages of dominant phytoplankton species with high Ks values for phosphorus and low Ks values for nitrogen have decreased since the 1980s,while those of dominant phytoplankton species with low Ks values for phosphorus and high Ks values for nitrogen increased during this period.展开更多
Based on survey data from April to May 2009, distribution and its influential factors of dissolved inorganic nitrogen (DIN) over the continental slopes of the Yellow Sea (YS) and East China Sea (ECS) are discussed. In...Based on survey data from April to May 2009, distribution and its influential factors of dissolved inorganic nitrogen (DIN) over the continental slopes of the Yellow Sea (YS) and East China Sea (ECS) are discussed. Influenced by the Changjiang (Yangtze) River water, alongshore currents, and the Kuroshio current off the coast, DIN concentrations were higher in the Changjiang River estuary, but lower (<1 μmol/L) in the northern and eastern YS and outer continental shelf area of the ECS. In the YS, the thermocline formed in spring, and a cold-water mass with higher DIN concentration (about 11 μmol/L) formed in benthonic water around 123.2°E. In Changjiang estuary (around 123°E, 32°N), DIN concentration was higher in the 10 m layer; however, the bottom DIN concentration was lower, possibly influenced by mixing of the Taiwan Warm Current and offshore currents.展开更多
文摘利用连云港海州湾2004年至2006年的水质监测资料,选取时间上完全同步的空间分辨率为500m的 MODIS Terra 1B 数据,对反射率的单波段因子和波段组合因子与可溶无机氮(DIN)质量浓度之间进行相关分析。从总体上看,单波段因子与 DIN 质量浓度的相关性较低,但在含氮基团倍频和合频吸收带附近的波段(波段2、7)反射率与 DIN 质量浓度呈负相关,显示了含氮基团对水体光谱特征的影响;在波段组合因子中,因子 F_(11(3,4))和 F_(13(3,4))与 DIN 质量浓度呈显著正相关,用这两个因子建立 DIN 质量浓度的回归模型,R^2达到0.7以上,相对精度达70%左右,最终选择因子 F_(11(3,4))的线性模型反演该海域的 DIN质量浓度,其结果与实际情况非常吻合。
基金Supported by the National Natural Science Foundation of China for Creative Research Groups by(National Natural Science Foundation of China)(No.40821004)the National Basic Research Program of China(973 Program)(No.2007CB407305)
文摘Systematic studies of the changes in dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphorus(DIP) and their effects on phytoplankton over the last 30 years in the Bohai Sea are presented.The amount of sewage disposal,use of fertilizer and the Huanghe River runoff were found to have a significant influence on the DIN or DIP concentrations in the Bohai Sea over the last 30 years.Moreover,the changes in DIN and DIP resulted in changes in the limiting nutrients of phytoplankton in the Bohai Sea from nitrogen in the early 1980s to nitrogen-phosphorus in the late 1980s,and then to phosphorus after the 1990s.In addition,changes in nitrogen and phosphorus had a significant effect on the phytoplankton community structure.The half saturation constant(Ks) was used to evaluate the effect of nutrients on the phytoplankton community structure in the Bohai Sea over the last 30 years.Cell abundance percentages of dominant phytoplankton species with high Ks values for phosphorus and low Ks values for nitrogen have decreased since the 1980s,while those of dominant phytoplankton species with low Ks values for phosphorus and high Ks values for nitrogen increased during this period.
基金Supported by the National Basic Research Program of China (973 Program) (Nos. 2010CB428701, 2005CB422305)
文摘Based on survey data from April to May 2009, distribution and its influential factors of dissolved inorganic nitrogen (DIN) over the continental slopes of the Yellow Sea (YS) and East China Sea (ECS) are discussed. Influenced by the Changjiang (Yangtze) River water, alongshore currents, and the Kuroshio current off the coast, DIN concentrations were higher in the Changjiang River estuary, but lower (<1 μmol/L) in the northern and eastern YS and outer continental shelf area of the ECS. In the YS, the thermocline formed in spring, and a cold-water mass with higher DIN concentration (about 11 μmol/L) formed in benthonic water around 123.2°E. In Changjiang estuary (around 123°E, 32°N), DIN concentration was higher in the 10 m layer; however, the bottom DIN concentration was lower, possibly influenced by mixing of the Taiwan Warm Current and offshore currents.
