Sustainable land use options for optimum resources use in maize based cropping system on uplands of Western Thailand

Worldwide, soil degradation due to erosion is still a major issue. Minimum tillage, intercropping, and alley cropping are important features of conservation agriculture and food security, but the farming communities are reluctant to accept these practices due to area reduction and plant competition. We investigated maize sole cropping (T1) as current farmers’ practice; T2: maize intercropped with chilies, tillage and fertilization; T3: maize-chili intercrop, mini. tillage, fertilization, Jack-bean relay cropping; T4: Like T3 but with hedges; T5 and T6 like T3 and T4, respectively, but without fertilization on Thai uplands during 2010 and 2011. Maize above ground biomass (AGB) was higher in T2 than T1 during both years. Light use efficiency (LUE) for AGB was 1.44–1.56 and 1.44–1.96 g DM MJ−1 in T4 during 2010 and 2011, 17–47% higher than T1, respectively. Land equivalent ratio was 1.23 and 1.17 in T2 while 1.28 and 1.21 in T4 during 2010 and 2011, respectively. Maize grain nitrogen (Ng) was significantly lower in unfertilized treatments. Intercropping with soil conservation enhanced land use efficiency with soil protection against erosion. Understanding spatial variations of LUE, Ng, as well as their impact on crop productivity are useful for fine-tuning crop management in conservation agriculture and sustainable land use on uplands.