Soil Quality Assessment of Tobacco Field Based on Minimum Data Set in Southwest Guizhou Autonomous Prefecture

LIU Zhiyong; LUO Fufang; LU Wanhua; ZHU Bo; LI Hongxun; LIU Zhangyong; CHEN Jie; YI Lixia

doi:10.15933/j.cnki.1004-3268.2024.07.011

Abstract：To clarify the soil quality characteristics of typical flue-cured tobacco planting areas in Southwest Guizhou Autonomous Prefecture,51 representative soil sampling points were selected to study the physicochemical properties and biological characteristics for topsoil(0-10 cm)and subtopsoil(10-20 cm).Concurrently,a minimum data set(MDS)was established based on principal component analysis(PCA)to evaluate the impact of varying tobacco cropping durations(Y1:0-10 years;Y2:10-20 years;Y3:over 20 years)on soil quality indicator(SQI)in tobacco-growing areas.The results of PCA indicated that MDS consisted of six indicators:soil organic matter,total nitrogen,total phosphorus,alkali-hydrolyzable nitrogen,available potassium content,and urease activity.The soil quality indicator(TDS-SQI,mean 0.589)of the total data set(TDS)was highly positively correlated with MDS-SQI(mean 0.581)(R2=0.993,P<0.01),suggesting that both MDS and TDS could be used to explain soil quality characteristics.Additionally,MDS-SQI showed a highly significant positive correlation with tobacco plant height and length of leaf,indicating a better growth condition of tobacco plants in areas with higher MDS-SQI values,and revealing the good representativeness of indicators belonging to MDS.There were no significant differences in SQI between different soil layers(0-10 cm and 10-20 cm);however,SQI of Y3(over 20 years)tobacco field was lower than that of Y2(10-20 years)and Y1(0-10 years),with a significant difference between Y1 and Y3 SQI values(P<0.05).In conclusion,six indicators including soil organic matter,total nitrogen,total phosphorus,alkaline hydrolyzable nitrogen,available potassium content,and urease activity can effectively evaluate the soil quality of tobacco fields in Southwest Guizhou Autonomous Prefecture;Long-term continuous cropping of tobacco leads to declining of soil quality.