Land use change from paddy rice to sugarcane under long-term no-till conditions: increase P balance, soil organic matter and sugarcane productivity

Abstract

Expanding sugarcane (SC) cultivation at the expense of paddy rice (PRC) areas led to soil nutrient cycling changes. The study hypothesized that SC straw return and fertilizer application after land use change (LUC) from PRC to SC cropping would increase the soil-crop systems nutrient balance, ultimately enhancing growth, yield, and nutrient use efficiency of SC. In a field study involving a 17-year chronosequence of sugarcane 6 (SC6), 13 (SC13), and 17 (SC17) years after LUC, the nutrient balance dynamics of SC were monitored in comparison with those of PRC. A phosphorus (P) balance increase of 62–102% after LUC increased soil available P (Pav) from 5.2 to 13.6–16.0 mg kg−1. A potassium (K) balance decrease of 47–55% after LUC led to a decrease in soil exchangeable K (Kex) from 102.5 to 96.2–56.8 mg kg−1. Moreover, LUC increased the % sand, soil organic matter (SOM), total mineral nitrogen (N), and total N. In contrast, the % clay, bulk density, cation exchange capacity (CECpH7), and exchangeable calcium (Caex) decreased after LUC. An increase in soil nutrients increased cane yield and nutrient use efficiency with time after LUC. However, further research in different locations and management practices is required for the LUC investigation.