CAJ | 학술논문

土壤含水量的时空分布与变化情况对土壤温度变化、陆地—大气间热量平衡以及陆面大气环流产生显著的影响，因此，对大范围内土壤含水量进行实时动态监测，获得某段时间内土壤含水量的连续变化情况具有重要的意义。研究目的是借助高光谱遥感手段，通过构建不同质量含水量的土壤反射率光谱模拟模型，深入了解土壤质量含水量与土壤反射率光谱之间的关系，为监测土壤含水量提供有效手段。利用ASD Field Spectral FR野外光谱仪和加水称重法获得北京市8个采样点的土壤样品不同质量含水量下的土壤反射率光谱实测数据，利用其中2个土壤样品不同质量含水量下的光谱数据构建含水土壤反射率光谱模拟模型，并利用未参与建模的另外6个土壤样品数据对该模型的模拟效果进行了检验。通过数据验证发现，当土壤质量含水量小于田间持水量时，该模型的模拟精度较高；而且对于不同的土壤样品，模型的模拟效果都比较好。最后又利用北京大学校园内三个采样点的实地测量光谱数据对模型进行了验证，光谱的模拟值与实测值之间的均方根误差最小可达0.0058。因此该模型可实现对质量含水量小于田间持水量的不同类型土壤的反射率光谱进行较高精度的模拟。
토양함수량적시공분포여변화정황대토양온도변화、륙지—대기간열량평형이급륙면대기배유산생현저적영향，인차，대대범위내토양함수량진행실시동태감측，획득모단시간내토양함수량적련속변화정황구유중요적의의。연구목적시차조고광보요감수단，통과구건불동질량함수량적토양반사솔광보모의모형，심입료해토양질량함수량여토양반사솔광보지간적관계，위감측토양함수량제공유효수단。이용ASD Field Spectral FR야외광보의화가수칭중법획득북경시8개채양점적토양양품불동질량함수량하적토양반사솔광보실측수거，이용기중2개토양양품불동질량함수량하적광보수거구건함수토양반사솔광보모의모형，병이용미삼여건모적령외6개토양양품수거대해모형적모의효과진행료검험。통과수거험증발현，당토양질량함수량소우전간지수량시，해모형적모의정도교고；이차대우불동적토양양품，모형적모의효과도비교호。최후우이용북경대학교완내삼개채양점적실지측량광보수거대모형진행료험증，광보적모의치여실측치지간적균방근오차최소가체0.0058。인차해모형가실현대질량함수량소우전간지수량적불동류형토양적반사솔광보진행교고정도적모의。
The spatio‐temporal distribution and variation of soil moisture content have a significant impact on soil temperature , heat balance between land and atmosphere and atmospheric circulation .Hence ,it is of great significance to monitor the soil mois‐ture content dynamically at a large scale and to acquire its continuous change during a certain period of time .T he object of this paper is to explore the relationship between the mass moisture content of soil and soil spectrum .This was accomplished by build‐ing a spectral simulation model of soil with different mass moisture content using hyperspectral remote sensing data .The spectra of soil samples of 8 sampling sites in Beijing were obtained using ASD Field Spectrometer .Their mass moisture contents were measured using oven drying method .Spectra of two soil samples under different mass moisture content were used to construct soil spectral simulation model ,and the model was validated using spectra of the other six soil samples .The results show that the accuracy of the model is higher when the mass water content of soil is below field capacity .At last ,we used the spectra of three sampling points on campus of Peking University to test the model ,and the minimum value of root mean square error between simulated and measured spectral reflectance was 0.005 8 .Therefore the model is expected to perform well in simulating the spec‐trum reflectance of different types of soil when mass water content below field capacity .