Terracing

In Maharashtra, terracing is initially done at Govt. cost and then the amount is recovered from cultivators as loan along with concessional rate of interest in suitable annual installments. 62p.c. of the loan is treated as subsidy. Terracing has become popular in Sahyadri ranges of Maharashtra. It is suitable on bigger slopes up to 10p.c., and where rainfall is higher than 1,250mm. Terrace bunds consist of comparatively narrow embankments constructed at intervals across the slope and the vertical spacing between bunds may vary from 1 to 2m., depending upon the slope, type of soil, rainfall etc. Bench terracing is done when gradient is steeper than 10 p.c., as a series of step like platforms along contours. These terraces are like tabletops sloping outwards and are provided with stone wasteweirs ot drain away surplus water. Angular and big boulders should be used for terrace outlets because round and small boulders will slip and get dislodged under the gushing water. Terracing is generally very costly and the cost may come to Rs.2,500 to 5,000 per hectare.

Terracing of side slopes: - The uneven side slopes of the medium gullies having 8 to 15% slope are bench-terraced into level terraces at 0.9 to 1.2m vertical intervals. The terraces are given a back slope of 1 in 50 and a longitudinal grade of 1 in 200 towards the grassed outlet. A ridge bund of 0.3 sq m cross-section is provided at the edge of each terrace. Terrace faces are given a slope of 1.5:1. Bench terraces are constructed when the gully sides are having a uniform slope for a length of at least 120m to justify the cost of terracing. The terrace faces, grassed outlets and earthen check dams are stabilized by sodding or growing them with suitable grasses. Dicanthium annulatum and Cenchrus ciliaris have been found suitable for this purpose, specially in Gujarat and in the ravines on the banks of the Jamuna river. Bench terraces and the check dams require careful maintenace for the first two years in view of the unsettled conditions of the soil. Bench terraces may be sloping outward or inward with or without a slight longitudinal grade, according to the rainfall of the tract medium, poor or heavy, and the soil and the subsoil are fairly absorptive or poorly permeable. On steeply sloping and undulating land, intersive farming can be practised only with bench-terracing. The initial cost of bench-terracing is more than that of bunding. However, bench-terracing helps to retain the soil, moisture, manure and fertilizer better and facilitates the application of irrigation, if available. In rainfed areas, terracing is usually practised on slopes ranging from 6 to 33 per cent. It may have to be used on gentle slopes, if irrigation is to be applied to the crop.

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