Arid Zone Research ›› 2023, Vol. 40 ›› Issue (12): 1907-1917.doi: 10.13866/j.azr.2023.12.04

• Land and Water Resources • Previous Articles     Next Articles

Main nutrient characteristics and influencing factors of farmland soil in the Loess Plateau of the Shaanxi Province

HE Junqi1,2,3(),BAI Hanwei1,2,3,XU Yiwei4,NI Lili5   

  1. 1. School of Water and Environmental, Chang’an University, Xi’an 710054, Shaanxi, China
    2. Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of Ministry of Education, Chang’an University, Xi’an 710054, Shaanxi, China
    3. Key Laboratory of Ecological Hydrology and Water Security in Arid Areas, Ministry of Water Resources, Chang’an University, Xi’an 710054, Shaanxi, China
    4. Shaanxi Science and Technology Exchange Center, Xi’an 710054, Shaanxi, China
    5. Shaanxi Province Farmland Quality and Agricultural Environmental Protection Workstation, Xi’an 710003, Shaanxi, China
  • Received:2023-06-06 Revised:2023-09-11 Online:2023-12-15 Published:2023-12-18

Abstract:

To explore the main soil nutrient characteristics and influencing factors of farmland in the Loess Plateau of Shaanxi, spatial analysis was conducted on the content of SOM, TN, AP, and AK using GIS and geostatistics methods based on the data from 5096 farmland sampling points with a depth of 0-20 cm in the study area. A geographic detector model was used to explore the degree to which 18 influencing factors explained the spatial variation of nutrients. The results showed that the average contents of SOM, TN, AP, and AK were 14.43 g·kg?1, 0.92 g·kg?1, 18.21 mg·kg?1, and 190.28 mg·kg?1, respectively, showing moderate variation. The four best-fit models for nutrients were all exponential models, with moderate spatial correlation among each nutrient. The combined effect of structural and random factors causes spatial differences in the nutrient content. The global spatial correlation of nutrients is TN > SOM > AK > AP. The regional differences in nutrient content are significant, indicating a gradually increasing trend from north to south. The single-factor effects of annual sunshine duration, annual average temperature, fertilizer use, and geomorphic type have stronger explanatory power for spatial variation in nutrient content but lesser than that of the interaction between the two factors. Research has shown that it is necessary to increase fertilizer input in the northern Shaanxi region, perform intensive cultivation in the Guanzhong region, and consider multiple factors in farmland construction.

Key words: main nutrients in soil, spatial variation, influencing factors, geological detector model, the Loess Plateau of Shaanxi Province