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The variability of soil qualities across the coffee‐growing areas and consequences of conversion of forest to coffee plantations on soil qualities and sustainability in the Western Ghats of South India are evaluated in this study by assessing and studying the six representative pedons selected from Chikmagalur district in Karnataka and Wayanad and Idukki districts of Kerala taking into consideration of the agro‐ecological zones, they belong. Sixty sites were located for monitoring soil quality, of which 46 sites were located in coffee plantations of all agro‐climates and 14 in forests adjacent to coffee plantations in similar setting. Soil quality indicators were selected by carrying out principal component analysis (PCA) on measured soil attributes, which provided 4 PCs in both land uses with eigen values > 1 and explaining at least 5 per cent variance in data set. The indicators for coffee land use were pH, exch. Al and CEC and for forest land use, organic carbon, pH and exch. Al. These indicators were transformed into scores following linear scoring method and soil quality index was determined, on a scale of 0–1, using the weighting factors obtained from PCA. Soil quality index was high (0.836) for natural forest land use, while it was medium (0.634) for coffee land use. Results indicated that organic carbon, pH and exch. Al are the most powerful indicators of soil quality. Proper management of soil acidity in coffee plantations due to liming, pooling back of nutrients, fertilization effect and other anthropogenic interventions in them have helped in maintaining a near equal soil quality to that of natural forest, which can be made sustainable by adopting effective plantation management practices. [ABSTRACT FROM AUTHOR]

Integrated landscape management of key population areas along with the corridors linking them is important for tiger conservation in the Indian subcontinent. Relationships between gene flow and landscape patterns, however, cannot be generalized given that different limiting factors influence movement in different spatial contexts. Here, we study the landscape features affecting tiger gene flow in the Western Ghats, and examine how and why limiting landscape features differ between Central India and the Western Ghats. We also assess whether these landscape features have been altered by land use changes in the last five decades. Our study area covers 30 000 km2 from Bhadra Tiger Reserve to the Nilgiri Biosphere Reserve in India. We used genetic data of 115 tigers and landscape resistance model optimization to create a resistance surface to gene flow in the Western Ghats. Tiger gene flow, both in Central India and the Western Ghats, is primarily related to topographic roughness and secondarily to diffuse disturbance, however these relations are inverted in the two landscapes ‐ in Central India, gene flow correlates with rough terrain, whereas in the Western Ghats, it correlates with smooth, forested terrain with minimal human disturbance. Topographic complexity is an important factor affecting tiger dispersal, but tiger's response to topography seems to be dependent upon interactions with human‐related disturbance. Tigers in Central India favor rough terrain for dispersal primarily because it is the only part of the landscape without heavy human footprint and the last refuge for natural vegetation, whereas in the Western Ghats, forest cover is more extensive in flatter terrain and human footprint is generally lower. [ABSTRACT FROM AUTHOR]