为研究高分一号(GF-1)卫星数据监测太湖水质的可行性,基于新发射的GF-1卫星16 m分辨率的多光谱宽覆盖(wide field of view,WFV)相机和HJ-1A CCD数据,对太湖的叶绿素a、悬浮物、透明度和富营养化状况进行遥感监测,以评价GF-1 WFV相机的...为研究高分一号(GF-1)卫星数据监测太湖水质的可行性,基于新发射的GF-1卫星16 m分辨率的多光谱宽覆盖(wide field of view,WFV)相机和HJ-1A CCD数据,对太湖的叶绿素a、悬浮物、透明度和富营养化状况进行遥感监测,以评价GF-1 WFV相机的应用潜力。研究结果表明:GF-1 WFV与HJ-1A CCD数据对水质参数的反演结果具有一致性,可有效反映叶绿素a浓度、悬浮物浓度、透明度和富营养化指数的空间变化规律。其中,太湖西北部分布有少量水华蓝藻,在大面积蓝藻爆发区域附近,叶绿素a浓度明显高于其他区域的水体,平均浓度为62.46 mg·m-3;悬浮物浓度以竺山湾及西部沿岸湖区较大,沿西北向东南方向递减,平均浓度为26.07 mg·L-1;透明度整体从西北向东南递增,与悬浮物浓度的分布趋势相反,平均值为22.1 cm;富营养化指数整体从西北向东南递减,与叶绿素浓度的分布趋势相同,平均值为69.62。遥感监测指标的结果均符合常规监测规律。展开更多
Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore wat...Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen （DIN） and phosphate （PO4-P） occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index （El）, Trophic index （TRIX） and Assessment of Estuarine Trophic Status （ASSETS） methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices： influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf.展开更多
基金Supported by the Natural Science Foundation of Guangxi Province,China(Nos.2012GXNSFEA053001,2010GXNSFE013001,2011GXNSFE018002,2011GXNSFA018108)
文摘Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen （DIN） and phosphate （PO4-P） occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index （El）, Trophic index （TRIX） and Assessment of Estuarine Trophic Status （ASSETS） methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices： influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf.
