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Abstract. This paper attempts to provide information for policymakers and soil conservation planners in the form of district-wise soil erosion risk (SER) maps prepared for the state of Telangana, India. The SER values for each district were computed by extracting the information on grid-wise soil erosion and soil loss tolerance limit values existing on the country-scale in a GIS environment. The objectives of the study were to (i) identify the areas of the state with a high erosion risk, and (ii) identify areas with an urgent need of conservation measures. The results reveal that around 69 % of the state has a negligible risk of soil erosion above the tolerance limits, and does not call for immediate soil conservation measures. The remaining area (2.17 M ha) requires conservation planning. Four districts, viz. Adilabad, Warangal, Khammam, and Karimnagar are the most risk-prone with more than one-quarter of their total geographical areas showing net positive SER values. In order to obtain a clearer picture and categorize the districts based on their extent of vulnerability, weighted erosion risk values were computed. Adilabad, Warangal, and Khammam were identified as the worst-affected districts in terms of soil erosion, and therefore are in need of immediate attention of natural resource conservation.

Degraded sites like mine spoils on hillslopes are characterized by poor soil physico‐chemical environments and instability. Reclamation of such areas using low cost bioengineering and vegetative methods were carried out in an abandoned limestone mine in the lower western Indian Himalayas and the impact of these measures on vegetation diversity, secondary succession and growth of seeded Acacia catechu Willd. after two decades of protection are reported in this paper. Results reveal that introduction of fast growing leguminous species affected species diversity and hampered the regeneration and growth of native vegetation, due to the dense shade of the over‐storey component. Species diversity (H') levels increased with the opening of the canopy at different elevations, with the highest diversity (1·624) being recorded on the hilltop with Acacia catechu and Wedlandia exserta dominating the area. Enumeration of various species in the growth stages indicated a large population in the pole stage followed by tree and sapling stage indicating scattered regeneration mostly by 1‐2 species. Tree associations in the lower, middle and upper reaches were of Leucaena leucocephala—A. catechu, A. catechu—Boehemeria rugulosa and A. catechu‐W. exserta, respectively. Seeded A. catechu plants now in the tree stage have attained an average height of 5·5 m and dbh of 10·44 cm with an average wood volume of 0·027 m3 in a period of 16–21 years. At current prices of heartwood (US $435 per m3) of A. catechu which is used in the manufacture of ‘kattha’, the investments made two decades ago (US$ 13043) in the rehabilitation of the limestone mine are fairly justified. Copyright © 2010 John Wiley & Sons, Ltd.

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