MATTIGA PANOMTARANICHAGUL1, SIVAPONG NAREUBAN2
1Chiang Mai University, Department of Soil Science and Conservation, Thailand
2Ministry of Agriculture and Agricultural Co-operative, Maehongson Research and Technology Service Centre, Thailand
This experiment aims to evaluate the effects of water harvesting strategies and anti-erosive cultural practices on the improvements of soil and water conservation for sustainable rainfed multiple crop production on sloping land. The field trials (Sites A and B) in Borkrai Village, Northern Thailand, consisted of 12 sub plots (5 x 30m) each site, with rotations of maize (Zea mays) followed by upland rice (Oryza sativa) and lablab bean (Lablab purpureous). The experiment was a completely randomised design (CRD) with three replicates of 4 anti-erosive cultural practices, (i) Conventional contour planting (CP), (ii) Contour furrow cultivation and alley cropping with the hedgerows of mixed fruit trees (CF -AL), (iii) Contour furrow cultivation with mulching and alley cropping (CF-M-AL), and (iv) Conventional contour planting and alley cropping + vetiver grass rows (CP -AL-VG). The measured data were top soil chemical and physical properties, surface runoff and soil loss, 1m soil water content profile, crop total dry biomasses and yields.
The results obtained from Site A (which were similar to Site B) during the first experimental year are described as follows. (i) CF-M-AL tended to give better soil properties than the other treatments. (ii) The lowest surface runoff and soil loss occurred in CF-M-AL plots (87 m3 ha-1 and 57 t ha-1) while the highest amounts were found in CP plots (132 m3 ha-1 and 315 t ha-1), compared to CF-AL plots (92 m3 ha-1 and 90 t ha-1) or CP-AL-VG plots (97 m3 ha-1 and 189 t ha-1). (iii) The highest amount of mid-dry season soil water contents (1m soil depth) was obtained under CF-M-AL (165 mm), compared to CP (133 mm) or CF-AL (139 mm) or CP-AL-VG (125). (iv) Maize yields was the lowest under CP (4.32 t ha-1) compared to CF-M-AL (7.20 t ha-1), CF-AL (6.20 t ha-1) and CP-AL-VG (5.87 t ha-1). CF-M-AL gave the highest total biomass yield of maize and lablab beans compared to the other treatments. The results indicated that contour furrow cultivation with mulching (CF-M-AL) was the best while conventional contour planting (CP) was the worst strategy for soil and water conservation, and multiple crop production improvement.
Keywords: Alley cropping, anti-erosive, contour furrow cultivation, multiple cropping, water harvest