Impact of National Highway (Nh-22) Expansion Activities on Soil Microbial Diversity in Forest Located Along Shoghi-Shimla Dhali Bypass, Himachal Pradesh, India

Abstract

The study was conducted to analyze the impact of highway expansion activity on soil microbial diversity. The study area was divided into four equal sites based on distances viz. Site 1, Site 2, Site 3 and Site 4. The surface soil samples from each site were collected at three horizontal distances from the edge of the National Highway during pre- monsoon and post-monsoon seasons. The horizontal distances to collect the soil data considered were 0–10-meter, 10-10 meter and > 20 meter which were replicated four times in randomized block design. The total microbial count in the surface soil lies in between from 31 x 106 cfu /g to 156 x 106 cfu/g. The highest value of total microbial count 156 x 106 cfu /g was recorded in pre-monsoon season at a distance of > 20 m at Dhali and lowest of 31 x 106 cfu /g at a distance of 0-10 m in post-monsoon season at Raghanv. The spatial variation showed an increasing trend with the increasing distances from the highway