基于季节分异的太湖叶绿素浓度反演模型研究

第11卷 第4期2007年7月

遥 感 学 报

J OURNAL OF REMOTE SENSI N G

V o.l 11,N o .4

Ju l y ,2007

收稿日期:2006-05-31;修订日期:2006-11-23

基金项目:国家自然科学基金项目: 湖泊水质高光谱遥感监测的机理模型研究 (编号:40571110)。

作者简介:乐成峰(1982 ),男,现为南京师范大学地图学与地理信息系统专业硕士研究生,主要从事水质遥感研究。E -ma i :l lcf 320@126.co m 。

文章编号:1007-4619(2007)04-0473-08

基于季节分异的太湖叶绿素浓度反演模型研究

乐成峰,李云梅,孙德勇,王海君

(南京师范大学江苏省地理信息科学重点实验室,江苏南京 210097)

摘 要: 叶绿素浓度反演算法主要有经验方法、半经验/分析方法和分析方法,其中半经验/分析方法应用最为广泛。但是反演的模型以及模型中的参数和反演精度都随着水体中叶绿素浓度的变化而改变。不同的季节水体中叶绿素浓度不同,水体反射光谱曲线特征和与叶绿素浓度相关性较高的敏感波段也不一致,使得各季节选用的反演模型和模型中的参数也存在一定的差异。本文在对2005年1 10月份叶绿素a(Chla)浓度季节差异进行分析的基础上,对4 10月份同步测量的水体光谱数据分春、夏、秋三个季节进行分析,分季节建立叶绿素浓度反演模型,并对它们进行比较,旨在为各季节选择最佳的反演模型。研究结果表明:春季和秋季选用波段比值算法反演精度较高,其中对数模型,线性模型和一元二次模型都有较高的相关性;夏季选用微分算法较好,该算法所建立的三种模型均具有较高的相关性。

关键词: 季节分异;太湖;Ch l a 浓度;反演模型中图分类号: TP701 文献标识码: A

R esearch on Chlorophyll Concentration R etrievalM odels of Tai hu L ake Based on Seasonal D ifference

LE Cheng -feng ,L IY un -m e,i S UN D e -yong ,WANG H a-i jun

(Jian g su P rovi n ci a lL ab .of Geog ra ph i c Infor m ati on Sci encesN anjin g N or m al University ,Jian g su N anji ng 210097,C hina )

Abstract : R etrieval chlorophyll conce ntrat i on models could be classified i nto t hree categories ,na me l y

e m pirical appr oach ,se m -i e m pirical/analytical approac h and a nalyt ical appr oach .Am ong those a l gorithm s ,the se m -i e m pirical/analytical algorith m i s app lied w i del y .But as c h l orophyll c oncentration changes ,retrieval

models asw ell as para m eter in mode ls a nd retrieval precision are c hanged accordi ngly .D ifferent season has d ifferent chl orophyll concentrati on in water body ,character of w ater reflect -spectr a l and sensiti v ity band whic h are better relate d to chl orophyll concentration also have difference ,resulting in the d ifference i n retrievalm odels and para m eters i n models f or each season .Th i s paper first analyzes the seasonal d ifference of chl orophyll a (Chla)concentrati on data whic h w ere collected fro m Januar y to O ctober i n 2005,and the n analyzes reflect -spectral data whic h were collected sync hronous w ith w ater sa m ple fro m A pril to O ctober i n 2005.W e di v i ded the tm i e span i nto spring ,summer and autumn ,built differe nt models for the t hree seasons and co mpared the m,so as to buil d an optm i al model for each season .The research result i ndicates that :in spri ng and aut umn ,the band -ration algorith m has better retrieval precisi on ,a m ong differe nt m odels ,logarith m mode,l li nerm odel and quadratic equation model has h i gher relat i v ity ;

i n summ er ,differential algorithm has better retrieval result ,

three models bu ilt dependent on the algorith m has h i gh relativity .K ey words : season d ifference ;T ai hu Lake ;Chla concentration ;retrieval m odels