干旱区生态环境知识资源中心

The Micro-catchment Water Harvesting (MCWH) technique has been practiced in several parts of the world, including Iran, in order increase crop production on drylands. However, its effects on plant growth and yield have not been studied effectively. This research has been conducted in order to study the influence of MCWH on vegetative growth, yield, and yield per cluster of dryland grape vine for six years in a semi-arid region of the Fars province, Iran.

The experimental sight was located on a gravely loam soil (54% gravel), with an average slope of 5-6%. The MCWH system consisted of small plots of 6.7x2.0 m(2), confined by small ridges (20-25 cm in height). Trees were located at the lower end of the slopes of the plots, and hence the runoff is directed towards the trees. The annual rainfall varied between 244 and 548 mm, and mostly occurred during November to late April. The study area had a low runoff potential. The annual runoff varied between 13.5 and 42.5 mm. The average increase in the soil water content, at a depth of 0-120 cm in the MCWH plots, were 4.2 - 9.9% with respect to the control during the different years. The average increase in the grape yield, and yield per cluster were 36.4 and 26.5% respectively. Furthermore, a multiple regression equation has been given in order to predict the grape yield per tree as a function of annual water infiltrated under the tree (rain and runoff), rainfall in April (the Persian month of 'Ordibehesht'), and the average monthly temperature in February (the Persian month of 'Bahman') of the previous year. Even though the runoff potential of the MCWH system was low in the study region, this system has increased the vegetative growth, grape yield, and the yield per cluster, due to the increase in the soil water content. Therefore the MCWH, without any surface modification, was effective in increasing the growth and yield production in this study area.