摘要本研究以浙江省具有代表性的城市湿地湘湖及西溪湿地为研究对象,通过对观测点的测量获得了水体的表观光学参数、水体中藻类颗粒吸收系数以及叶绿素浓度等信息。分析表明了在湘湖观测点叶绿素在11:00-15:00呈上升趋势在15:00后下降,西溪湿地各个不同观测点的叶绿素浓度受外界因素影响存在着比较大的差异;通过藻类颗粒吸收系数的特征,分析藻类颗粒的光学特性,发现湘湖观测点藻类颗粒吸收系数在夏季比秋季要高,而在西溪湿地观测点春季的藻类颗粒吸收系数比秋季的高;由测量的观测点ASD信号绘制了观测点水体遥感反射率曲线,并且分析遥感反射率的特征峰与藻类叶绿素之间的关系。进一步分析2015年3月西溪湿地叶绿素a浓度以及相应观测点的遥感反射率之间的关系,通过对遥感反射率进行归一化处理,计算二者的相关性,并选择高相关系数的波段建立统计回归模型。结果表明:基于归一化反射率单波段建立的线性回归模型中,R675与R482拟合度最高;而在基于归一化反射率波段比值建立的线性及二项式模型中,利用波段比R675/R482建立的二项式模型的拟合效果最好。48256
Abstract
In this study the typical urban wetland Xianghu Lake and Xixi Wetland in Zhejiang Province were taken as the research objects. We obtained the information such as apparent optical parameters of the water, algae particle absorption coefficient of the water and chlorophyll concentration. The analysis indicated that chlorophyll concentration at Xianghu observation sites kept an increasing trend between 11:00am and 3:00pm, and gradually decreased after 3:00pm. Chlorophyll concentration at different observation sites of Xixi Wetland showed great difference because of the influence of many environmental factors. Based on the characteristics of the absorption of algae particles, we analyzed the optical characteristics and gave a conclusion that absorption coefficient of algae particles in Xianghu Lake was higher in autumn than in summer, while absorption coefficient of algae particles in Xixi Wetland was higher in autumn than in spring. We derived remote sensing reflectance from ASD data; and analyzed the relationship between the characteristic peaks and chlorophyll concentration. Further analysis was made to find out the relationship between chlorophyll a concentration and remote sensing reflectance at corresponding observation sites in Xixi Wetland in 2015.The correlation between chlorophyll a concentrations and normalized reflectance were analyzed. The bands with high correlation coefficients were selected to build statistical regression model. Results indicated that single bands as R675 and R482 reached the highest fitting precision in all linear regression, and the binomial model with combined bands as R675/R482 made the best fitting in all linear and binomial models.
毕业论文关键词:湿地; 藻类; 叶绿素;吸收系数;遥感反射率; 回归模型
Keyword: Wetland; Algae; Chlorophyll; Absorption coefficient; Remote sensing reflectance; Regression model
目录
第一章 引言 4
第二章 研究思路与研究内容 5
第一节 研究思路 5
第二节 研究内容 5
一、叶绿素浓度的测量与分析 5
二、藻类颗粒吸收系数测量与分析 6
三、水体遥感反射率的测量与分析 6
四、水体遥感反射率与叶绿素a相关性分析 6
第三章 数据的采集与观测准备 7 湿地水体水色要素藻类颗粒现场调查及分析:http://www.751com.cn/shengwu/lunwen_50797.html