Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Chine → 2021 → Soil Salinity Inversion and Soil Quality Assessment in Oasis of Manas River Basin

Shihezi University (石河子大学) 2021

Soil Salinity Inversion and Soil Quality Assessment in Oasis of Manas River Basin

杨小虎

Titre : Soil Salinity Inversion and Soil Quality Assessment in Oasis of Manas River Basin

Auteur : 杨小虎

Grade : Master 2021

Université : Shihezi University (石河子大学)

Résumé partiel
he Manas River Basin,one of the four major irrigated agricultural areas in Xinjiang,is the first area in China to achieve large-scale drip irrigation.Long-term drip irrigation conditions affect the law of soil salt transport,so it is particularly important to explore the temporal and spatial changes of salinized soil,influencing factors,and comprehensive evaluation of soil quality at the catchment scale.【Methods】The oasis of Manas River Basin is selected as the research area.Based on the combination of remote sensing data and field measured data,an inversion model of soil salinity is constructed.The spatio-temporal evolution characteristics of soil salinization in the study area are explored.Based on SEBS model,the regional evapotranspiration is inversed in order to analyze the effect of evapotranspiration on soil salinization.And the soil quality of salinized soil is evaluated using soil quality comprehensive index method.【Results】The main research results are as follows :(1)The remote sensing indexes selected in this paper are normalized vegetation index,ratio vegetation index and soil regulation vegetation index,and the correlation coefficients with soil salinity are-0.746,-0.663 and-0.733,respectively.The coefficient of determination(R2)of the combined model constructed by the single prediction model is 0.797,and the root mean square error(RMSE)is 3.111.Compared with PLSR and BPNN model,the R2 of the combined model is improved by 0.038 and 0.094,respectively.Compared with the single model,the combined model can more accurately predict the current status of soil salinization in the study area.(2)Surface soil salinity from 1996 to 2019 inversed using the combined model.The analysis shows that the saline soil in the study area has gradually changed to heavy and moderately salinized soil,and the moderately and heavily salinized soil has gradually changed to lightly salinized and non-salinized soil.The area of moderately and heavily salinized soil is large,and there is a potential risk of secondary salinization.78.02%of the soil salinization in the study area has been sign SQIcantly improved,and 10.09%of the soil salinization has been sign SQIcantly worsened.Soil salinization has been prevented effectively after a long time and large area drip irrigation under the mulch

Mots clés : Manas River Basin ;Salinity inversion ;Combination model ;Evapotranspiration;Soil quality evaluation ;

Présentation (CNKI)

Page publiée le 8 mars 2022