| 摘要: |
| 通过在江苏射阳河口现场采集光谱和水样, 将实测光谱重采样为北京一号的波段反射率并与可溶性无机氮(DIN)和可溶性无机磷(DIP)浓度作相关性分析。结果表明, 北京一号的近红外和红波段与DIN、DIP浓度呈强烈的正相关, 这反映了沉积物的再悬浮作用是该海域营养盐的重要来源; 与DIN、DIP浓度相关性高的主要波段组合因子是由近红外波段与绿波段以及红波段与绿波段的比值或差值构成的因子, 其相关性高于单波段因子。最终选择因子F10(3, 1)的三次多项式模型作为该海域DIN、DIP浓度定量反演模型。模型相对浓度较高的样本组(DIN≥200μg/L, DIP≥20μg/L)其预测精度分别为73.69%和73.45%, 而该海域DIN、DIP浓度的均值远远超过了上述阈值, 影像反演结果也与实际情况高度吻合, 反映了模型在该海域的实际应用价值。 |
| 关键词: DIN浓度 DIP浓度 射阳河口 北京一号小卫星 遥感 |
| DOI：10.11693/hyhz20120831002 |
| 分类号: |
| 基金项目:国家自然科学基金项目, 41071083 号; 江苏省高校自然科学研究面上项目, 11KJB170010 号; 盐城师范学院教授、博士基金, 10YSYJB0207 号。 |
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| DETERMINE CONCENTRATIONS OF NITROGEN AND PHOSPHORUS IN ESTUARY WITH SATELLITE IMAGE |
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XU Yong1,2, CHENG Chang-Chun1,2, ZHANG Ying3, ZHANG Dong3
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1.School of Urban and Resource Environment, Yancheng Teachers University, Jiangsu Province;2.Research Institute of Jiangsu Coastal Development, Jiangsu Province;3.College of Geography, Nanjing Normal University
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| Abstract: |
| Using in-situ measured spectrum, we simulated the reflectance of multi-spectral image taken by satellite Beijing-1 and calculated the correlations between simulated reflectance and concentrations of dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) in Sheyang River estuary in northern Jiangsu Province, Yellow Sea, East China. Results show that near-infrared and red bands have greater positive correlations with DIN and DIP concentrations than that of green band, indicating that resuspended sediment is an important source of nutrients in the estuary. Multi-band factors are more closely correlated with DIN and DIP concentrations than single band factors do, which is caused mostly by the difference or ratio of near-infrared and green bands. After comparing R2 and relative accuracy, the cubic models established by F10(3, 1)factor are chosen to retrieve DIN and DIP concentrations. The value R2 of DIN and DIP models arrive at 0.645 and 0.730, respectively. The accuracy of the models under relatively high concentration conditions (DIN≥200μg/L, DIP≥20μg/L, which are well below the average value in this area) arrive at 73.69% and 73.45%. The retrieved results are well consistent with the real conditions and errors between the retrieved results and in-situ data are
lower than errors of whole sample set. The model therefore, was proved effective. |
| Key words: DIN concentration DIP concentration Sheyang River estuary Beijing-1 Micro-satellite remote sensing |
