光谱学与光谱分析
光譜學與光譜分析
광보학여광보분석
SPECTROSCOPY AND SPECTRAL ANALYSIS
2014年
6期
1649-1655
,共7页
毛海颖%冯仲科%巩垠熙%于景鑫
毛海穎%馮仲科%鞏垠熙%于景鑫
모해영%풍중과%공은희%우경흠
多光谱%遗传算法%土壤类型%土壤含水量%永定河
多光譜%遺傳算法%土壤類型%土壤含水量%永定河
다광보%유전산법%토양류형%토양함수량%영정하
Multispectral technology%Genetic algorithm%Soil type%NDWI%Yongding River
永定河流域的土壤类型及含水量与植被覆盖指数是影响该流域水量的重要因素,利用传统取样法对该流域土壤类型及含水量进行调查,耗费人力的同时还会因仪器误差等客观因素造成实验精度下降。选择永定河流域(北京地区)为研究区,利用全站仪进行野外调查测定34块样地并取样,结合1978-2009年6期的TM影像数据对土壤信息进行提取,研究该地区的土壤含水量与各类多光谱遥感因子间的相关关系,利用遗传算法对土壤归一化水体指数(NDWI)的主要影响因子进行筛选,因NDWI 是基于绿波段与近红外波段的归一化比值指数,一般用来提取影像中的水体信息,效果较好。为了更准确的筛选与土壤含水量相关的因子,利用遗传算法全局择优的特点,通过控制迭代次数加速收敛来筛选关键因子。进而利用多元回归的方法建立NDWI反演模型,分析出模型的内符合精度为0.987,并利用边缘树种进行外符合精度检验,得出:土壤中速效氮、磷、钾的含量与经度相关性不明显,却与纬度和土层成正相关关系,当模型计算的迭代次数Maxgen达到最优时,内符合精度为87.6%。通过遥感影像与野外调查相结合的方法得到的土壤NDWI与植被盖度、地形、气候等相关因子的模型而计算得出的NDWI值与单纯利用传统土壤取样法得到的值进行对比分析,得出平均相对误差E为-0.021%,外符合精度P 达到87.54%。该模型的建立可为日后对永定河流域土壤水分及有机质的分析与研究提供较好的实践及理论依据。
永定河流域的土壤類型及含水量與植被覆蓋指數是影響該流域水量的重要因素,利用傳統取樣法對該流域土壤類型及含水量進行調查,耗費人力的同時還會因儀器誤差等客觀因素造成實驗精度下降。選擇永定河流域(北京地區)為研究區,利用全站儀進行野外調查測定34塊樣地併取樣,結閤1978-2009年6期的TM影像數據對土壤信息進行提取,研究該地區的土壤含水量與各類多光譜遙感因子間的相關關繫,利用遺傳算法對土壤歸一化水體指數(NDWI)的主要影響因子進行篩選,因NDWI 是基于綠波段與近紅外波段的歸一化比值指數,一般用來提取影像中的水體信息,效果較好。為瞭更準確的篩選與土壤含水量相關的因子,利用遺傳算法全跼擇優的特點,通過控製迭代次數加速收斂來篩選關鍵因子。進而利用多元迴歸的方法建立NDWI反縯模型,分析齣模型的內符閤精度為0.987,併利用邊緣樹種進行外符閤精度檢驗,得齣:土壤中速效氮、燐、鉀的含量與經度相關性不明顯,卻與緯度和土層成正相關關繫,噹模型計算的迭代次數Maxgen達到最優時,內符閤精度為87.6%。通過遙感影像與野外調查相結閤的方法得到的土壤NDWI與植被蓋度、地形、氣候等相關因子的模型而計算得齣的NDWI值與單純利用傳統土壤取樣法得到的值進行對比分析,得齣平均相對誤差E為-0.021%,外符閤精度P 達到87.54%。該模型的建立可為日後對永定河流域土壤水分及有機質的分析與研究提供較好的實踐及理論依據。
영정하류역적토양류형급함수량여식피복개지수시영향해류역수량적중요인소,이용전통취양법대해류역토양류형급함수량진행조사,모비인력적동시환회인의기오차등객관인소조성실험정도하강。선택영정하류역(북경지구)위연구구,이용전참의진행야외조사측정34괴양지병취양,결합1978-2009년6기적TM영상수거대토양신식진행제취,연구해지구적토양함수량여각류다광보요감인자간적상관관계,이용유전산법대토양귀일화수체지수(NDWI)적주요영향인자진행사선,인NDWI 시기우록파단여근홍외파단적귀일화비치지수,일반용래제취영상중적수체신식,효과교호。위료경준학적사선여토양함수량상관적인자,이용유전산법전국택우적특점,통과공제질대차수가속수렴래사선관건인자。진이이용다원회귀적방법건립NDWI반연모형,분석출모형적내부합정도위0.987,병이용변연수충진행외부합정도검험,득출:토양중속효담、린、갑적함량여경도상관성불명현,각여위도화토층성정상관관계,당모형계산적질대차수Maxgen체도최우시,내부합정도위87.6%。통과요감영상여야외조사상결합적방법득도적토양NDWI여식피개도、지형、기후등상관인자적모형이계산득출적NDWI치여단순이용전통토양취양법득도적치진행대비분석,득출평균상대오차E위-0.021%,외부합정도P 체도87.54%。해모형적건립가위일후대영정하류역토양수분급유궤질적분석여연구제공교호적실천급이론의거。
Basin soil type,moisture content and vegetation cover index are important factors affecting the basin water of Yong-ding River,using traditional sampling method to investigate soil moisture and the watershed soil type not only consuming a lot of manpower and material resources but also causing experimental error because of the instrument and other objective factors.This article selecting the Yongding River Basin-Beijing section as the study area,using total station instruments to survey field sam-pling and determination 34 plots,combined with 6 TM image data from 1978 to 2009 to extract soil information and the relation-ship between region’s soil type,soil moisture and remote sensing factors.Using genetic algorithms normalization to select key factors which influenced NDWI,which is based on the green band and near-infrared bands normalized ratio index,usually used to extract water information in the image.In order to accurate screening and factors related to soil moisture,using genetic algo-rithms preferred characteristics,accelerate the convergence by controlling the number of iterations to filter key factor.Using multiple regression method to establish NDWI inversion model,which analysis the accuracy of model is 0. 987,also use the spe-cies outside edges tree to meet accuracy test,which arrived that soil available nitrogen,phosphorus and potassium content and longitude correlation is not obvious,but a positive correlation with latitude and soil,inner precision researched 87. 6% when the number of iterations to achieve optimal model calculation Maxgen.Models between NDWI and vegetation cover,topography,cli-mate ect,through remote sensing and field survey methods could calculate the NDWI values compared with the traditional val-ues,arrived the average relative error E is -0. 021%,suits accord P reached 87. 54%.The establishment of this model will be provide better practical and theoretical basis to the research and analysis of the watershed soil moisture and organic of Yongding River.