Investigating soil quality in cold highland agricultural fields with different soil types

Abstract

ABSTRACT To evaluate the soil quality of alpine farmland and elucidate the key factors influencing productivity levels under the current agricultural paradigm, we conducted an extensive collection of soil samples. In total, 234 soil samples (0–20 cm) were collected from Menyuan County, the heartland of the southern slope of the Qilian Mountains. These samples represented four predominant soil types, including cold calcic soil, luvic chernozem, calcareous meadow soil, and calcareous gray cinnamon soil. Moreover, by employing principal component analysis, we established a minimum data set (MDS) that encapsulated the essential parameters for the comprehensive evaluation of the soil quality of farmland in the study area. Upon evaluating the soil quality index, the rankings were as follows: luvic chernozem (0.63) > calcareous gray cinnamon soil (0.58) > calcareous meadow soil (0.58) > cold calcic soil (0.55). Overall, the results highlighted that the significant impact of soil total nitrogen (TN), available potassium (AK), and soil water content (SWC) on soil quality within the study area. Therefore, in the context of land management practices, careful attention should be paid to the management of soil TN, AK content, and SWC to avoid the degradation of cultivated land into abandoned fields.