Species Diversity, Soil Nutrients Dynamics and Regeneration Status of Sal (Shorea robusta) Forests in Western Himalayan Region of India

Sal (Shorea robusta) forest is found in an extensive array of conditions in Western Himalaya. It has been heavily used for commercial purposes. Thus, we did a study to gather the information on sal forests occupying a broad range of the Rajaji Tiger Reserve which spans across an extensive range in the Western Himalaya. We tested the species diversity, soil nutrients status, and regeneration potential of the Sal forest. Vegetation was sampled in 10 transects zone of 20×20 m2 plots covering an area of 10.0 ha area. Trees, saplings, seedlings, shrubs, and herbs were sampled along the transects in the Chilla forest division of the tiger reserve. Samplings were done every 200 m along the transect with the help of the Nested quadrat method. Altogether 64 species were recorded: 24 trees, 12 shrubs, and 28 herbs. Environmental variables like pH, organic carbon, total nitrogen, available potassium, available phosphorous, and soil texture were also recorded to observe the effects of these environmental variables into diversity attributes. The Shannon Weiner index for trees was 1.350, for saplings 1.774, for seedlings 1.679. For shrub species, it was1.96. The Shannon Weiner index for herbaceous species in the rainy season was 2.8, in winter it was 2.36 whereas in summer it was 2.46. We concluded that the management of sal has enhanced the diversity and soil nutrients dynamics in the study area. Sal diversity also has enhanced the growth of co-dominant species like Mallotus philippensis, Aegle marmelos, Listea chinensis, Naringi crenulata, Ehretia laevis, Cassia fistula, etc. in the study area. Although we did not find any seedlings of the sal during the present study, the regeneration potential of sal forest increasing with a greater number of associated species provide a favorable environment for sal species