Department of Soil Science, CCS Haryana Agricultural University, Hisar, Haryana, 125004.
1Present address: Directorate of Research, CCS, HAU, Hisar, 125004.
A study was conducted at NARP farm, Balsamand, CCS HAU, Hisar, to evaluate the effect of trenching on soil moisturc extraction pattern by twenty-year-old Acacia tortilis trees. A trench 1.5 m deep, 0.5 m wide and 30 m long was excavated on south and parallel to east-west side at a distance of 2 m from the tree line of block plantation. Pearlmillet was taken as a test crop beyond the trench. Soil moisture content at different depths (0–1.20 m) at a distance of 10 m and 20 m normal to tree line under two conditions viz. with trench and without trench at different times after a heavy rainfall (76 mm) were determined gravimetrically. It was found that the soil moisture content increased with depth in all the cases. The rate of increase of amount of water extracted from 0–1.20 m profile was appreciably less in trenching treatment than that under without-trenching treatment; the rate remained constant with distance, whereas, it was 27 per cent higher in 10 m as compared to that in 20 m under no-trech treatment. The amount of water content in 0–1.20 m was on an average 52 per cent higher in trenching than under no trenching treatment when time and distance factors taken together. It was observed that the grain yield of pearlmillet from 30 m x 15 m plot under trenching treatment was 683 per cent higher than that under no-trenching treatment. Practical implications of this study are: a) A. tortilis should not be planted on the field boundaries and on road sides, and b) if these trees are already planted then trenching technology may be practiced to check the moisture extraction-spread horizontally.
Acacia tortilis, desert eco-systems, moisture extraction, trenching
