Management of Ravines Through Anicuts and Afforestation

Abstract

Ravines, the product of natural erosion, indicate the worst form of land degradation. The principal types of water erosion are sheet and gully erosion. Sheet erosion causes the removal of surface soil in thin uniform layers, year after year, and, therefore, usually goes unnoticed. Erosion damages rangelands, croplands and infrastructures. The locked-up production potential of ravines in only three states of Uttar Pradesh, Rajasthan and Gujarat alone is estimated to 3 million tons of food grain annually. Efficient reclamation schemes can be had through sustainable agricultural practices, controlled grazing, construction of peripheral bunds, contour bunding, contour trenches, gully plugging, spillways, diversion channel, breaking the length of slopes into smaller units and by plantation. This will prevent further damage to the valuable land as well as increase the production from reclaimed lands.

Different types of mechanical structures were constructed in the in 20 ha area at research site. These structures were bori bandhan, earthen bunds, masonry structure, gabion structure and modified gabion. The total sediment stored against the structures constructed till date is 7346 m³ out of which 3100 m³ against the earthen structures (16 earthen and 1 bori bandhan), 1705 m³ against the gabion structures (three in numbers) and 2541 m³ in permanent structure (four in numbers). The study revealed that bori bandhan conserved 43.5 Mg ha⁻¹soil, and these structures were partially fitted with moderate rainfalls; the earthen bunds were average 25.3 Mg ha⁻¹ soil stored in each structure, and not suitable as breaks frequently and suitable only for very low rains. Whereas the masonry structures were found very good and most suitable to check the soil erosion, average 915.4 Mg ha⁻¹ soil stored against the masonry structures, gabion structures were tested, and results show that gabion stored 784.5 Mg ha⁻¹ soil with high spillage and found that there was problem of pilferage from below and the side. Modified gabions were constructed to resolve the problem of gabion and found that these structures are economical, effective with minimum soil loss and stored average 1204 Mg ha⁻¹ soil. The soil and water conservation through structures and afforestation is one of the most important components for management of ravine. This paper discusses the soil and water conservation from the anicuts and afforestation interventions that were found promising for improving productivity and reducing land degradation in different regions of India.