基于实测光谱的湖库总磷浓度估算研究——以贵阳市红枫湖为例

对百花湖的水体光谱和传统实测数据进行分析,建立总磷浓度分析模型,计算红枫湖总磷浓度分布。分析结果表明,归一化光谱反射率和一阶微分光谱分别与实测总磷浓度的相关性最高在波段688 nm和823 nm处,其相关系数分别达到0.794 2和-0.970 8,分别以波段688 nm处归一化光谱和823 mm处一阶微分光谱建立光谱拟合模型,波段823 nm处一阶微分光谱建立的拟合模型的决定系数最高,决定系数R2高达0.943 3;采用情人谷水库、小关水库、阿哈水库和万峰湖的光谱数据验证了该模型下的总磷浓度与水库水质状况非常接近,证明了该模型的有效性和实用性;利用模型计算得到红枫湖总磷浓度分布状况,分析其浓度分布原因与当地实际情况比较符合,说明该分析方法对湖库总磷分析的精准度比较高。

A total phosphorus concentration analysis model to obtain total phosphorus concentration distribution was established for Hongfeng Lake by the analysis of the water body spectrum and traditional measured data of Baihua Lake. The analysis results show that: The normalized spectral reflectance and first-order differential spectra have the highest correlations with the measured total phosphorus concentrations at the bands 688 nm and 823 nm, respectively, and the correlation coefficients reach 0.7942 and -0.9708, respectively. A spectral fitting model was established with the normalized spectral at 688 nm and the first-order differential spectra at 823 nm separately. The coefficient of determination of the fitting model established by the first-order differential spectrum at the 823 nm band was the highest, and the coefficient of determination R2 was as high as 0.943 3;The spectral data of the Qingrengu Reservoir, the Xiaoguan Reservoir, the Aha Reservoir and the Wanfeng Lake was tested, which show that the total phosphorus concentration under the model is very close to the reservoir water quality, which proves the validity and practicality of the model;the distribution of total phosphorus concentration in Hongfeng Lake was calculated by the model. The reason for the analysis of the concentration distribution is in line with the actual situation in the area, which shows that the analysis method has higher accuracy in the analysis of total phosphorus in the lake.