AGGARWAL, R.K.WALIA, KASHISH2018-12-182018-12-182018-09http://krishikosh.egranth.ac.in/handle/1/5810086028ABSTRACT The present investigation entitled “Environmental Impact Assessment Studies on Expansion of National Highway-22 in Himachal Pradesh” was conducted during the years 2015 to 2017 in the Department of Environmental Science, Dr. YS Parmar University of Horticulture and Forestry, Nauni-Solan, Himachal Pradesh. The impact of highway expansion on air, water and soil quality and on the socio-economic conditions of habitants was studied. The investigation further aimed to assess the carbon loss and changes in microclimate of the study area and lastly the Air Pollution Tolerance Index of native vegetation was evaluated for green belt establishment and environmental management plan was also developed. In order to study the effect of highway expansion activity on soil, water and air quality, the study area was divided into four equal sites based on distances viz. Site 1, Site 2, Site 3 and Site 4.The observations on different parameters at each site were recorded during pre-monsoon, monsoon and post-monsoon seasons and were replicated under randomized block design. The socio-economic impact of highway expansion on the habitants was assessed on the basis of pre-tested questionnaire. The assessment of carbon loss and changes in microclimatic conditions was done by collecting secondary data from the District Forest Office, Solan and weather data for past thirty years from Dr. YSPUHF, Nauni and API and APTI was computed to select most tolerant species for green belt development. The study revealed that SO2, NO2,, VOC’s, PM10, NRSPM and TSPM ranged from 6.41 to 7.98, 31.15 to 44.87, 2.97 to 6.82, 118.42 to 148.87, 183.62 to 231.29 and 3312.26 to 380.16 μg m-3, respectively. The concentration of PM10 was above the permissible limits. The AQI of the study area was categorised as “moderately polluted”. The surface water pH in the study area ranged from 7.04 to 7.61, EC from 0.20 to 0.32 dsm-1, TDS, TSS and TS from 102.04 to 166.58 mg l- 1, 10.58 to 30.12 mg l-1 and 124.25 to 186.54 mg l-1, respectively. BOD and COD of surface water ranged from 1.93 to 3.15 mg l-1 and 26.30 mg l-1 to 64.29 mg l-1, respectively. The concentration of chloride, nitrate, calcium and magnesium varied from 15.49 to 38.44 mg l-1, 3.60 to 6.04 mg l-1, 82.19 to 122.78 mg l-1 and 7.60 to 11.78 mg l-1, respectively. The concentration of heavy metals Cd, Cr, Pb and Fe in surface water ranged from 0.005 to 0.018 mg l-1, 0.021 to 0.049 mg l-1, 0.012 to 0.032mg l-1 and 0.153 to 0.328 mg l-1, respectively. The surface soil pH, EC and OC ranged from 7.19 to 7.62, 0.27 to 0.39dsm-1 and 0.42 to 1.31 per cent, respectively. NPK content in the soil ranged from 261.08 to 325.70 kg ha-1, 26.79 to 50.15 kg ha-1 and 190.27 to 224.34 kg ha-1, respectively. The soil carbon stock ranged from 7.61 to 23.79 Mg C ha-1.The concentration of heavy metals Cd, Cr, Pb and Fe in surface soil ranged from 0.016 to 0.029 mg kg-1, 0.047 to 0.017 mg kg-1, 2.83 to 0.25 mg kg-1 and 42.28 to 20.94 mg kg-1, respectively. The highway expansion significantly affected the residents in proximity of the highways as the total change of 0.013 ha in land holding per household was recorded and 64.70 per cent decrease in the annual income of the small scale entrepreneurs has been found. Loss of 122002.85 tonnes of carbon dioxide to the atmospheres was observed due to felling 39049 trees (including sapling, seedlings and poles). The region has experienced a rise of 0.35°C in mean minimum temperature, a fall of 0.03°C in mean maximum temperature and a decrease of 19.21 mm in annual rainfall from over the base years. The APTI of selected plants ranged from 8.50 to 23.50. The API of selected plants was in the order of C. fistula > L. leucocephala > T. ciliata >W. fruticosa > G. optiva > G. robusta. C. fistula with high APTI value and high API score resulted to be most tolerant species to pollution and therefore, can be suggested for green belt development. G.optiva with higher dust accumulation capacity of 0.112gm-2 than the other selected species can be suggested for plantation to lower the levels of dust in the atmosphere generated from expansion activities. A detailed, environmental plan has been suggested to lower the impacts of highway expansion activities on the environment and humans.ennullThesis