The mitigation potential of avenue tree species needs a sound understanding, especially for landscape planning or planting tree species on roadside, especially in city limits where there is huge traffic due to more number of vehicles. A preliminary study was conducted to investigate the impact of heavy traffic movement and pollution thereof on physiological functioning of Lagerstroemia speciosa trees planted on roadside in terms of carbon absorption, mitigation potential and adaptive behavior. Trees on roadside exhibited reduced carbon assimilation (36.7 ± 2.4%) and transpiration rate (42.14 ± 2.9%), decreased stomatal conductance (66.85 ± 3.87%), increased stomatal resistance (212.2 ± 11.25%), more leaf thickness (40.54 ± 3.25) and water use efficiency (9.4 ± 0.87%), and changes in lead (179.31 ± 10.24%) and proline (15.61 ± 1.92%) concentration in leaf tissues when compared to less traffic area (FRI campus). The impacts were also witnessed in the form of enhanced vapour pressure deficit of air (63.18 ± 4.94%) and leaf (45.72 ± 3.25%), and air temperature (3.2 ± 0.16%) and leaf temperature (9.0 ± 0.82%) along roadside trees. It was inferred that heavy traffic movements interrupt the physiological functioning of trees due to alteration in the surrounding environment as compared to non-traffic areas. The present study provides baseline information to further explore and identify the potential avenue tree species having significant mitigation potential and adaptive efficiency to heavy traffic movements for improving urban environment.

The aim was to investigate the role of seasonal changes of physico-chemical parameters in forest soil of Doon Valley of Uttarakhand, India. The samples were collected from four different environmental conditions viz. urbanized area, industrial area, urbanization with dense forest area, and wetland area during summer, monsoon, and winter seasons from two different depths of 0-15 cm and 15-30 cm, respectively. The soil parameters were analyzed such as pH, total nitrogen, total phosphorous, total hydrogen, total carbon, organic carbon, inorganic carbon, exchangeable cations such as sodium, potassium, calcium, and magnesium. The result revealed that site-I and IV of both depths were found to be of good quality due to less human interference, low urbanization effect, and covered by the forest area whereas site-II and III were confirmed of poor quality. Pearson's correlation coefficient analysis suggest soils at both depths has following relation: total carbon and nitrogen (r = 0.90), magnesium and potassium (r = 0.74), Ca with N, P, C, OC, Na, K, Mg, organic carbon and total phosphorous (r = 0.85), organic carbon and nitrogen (r = 0.91). Hence, the soil fertility is good and very important for plant growth and development in agriculture process for sustainable development.

The accumulation of heavy metals in soil at roadside has been studied by the analysis of top soil/dust samples. Concentration of the elements Co, Cr, Pb and Cd were measured on 39 top soil/dust samples collected from near the highways, industrial area and control site. The samples were analysed for Zn, Cu, Fe, Mn, Pb, Cd, Ni, and Cr by using atomic absorption spectrophotometer (AAS). The mean concentrations of Co, Cr, Pb and Cd were 0.390, 0.090, 2.195 and 0.094 mg kg-1, respectively. Data obtained from analysis, were statistically examined to know the distribution of metals in different highways and industrial area. The results showed that the topsoil/dust near the highway and industrial sites had significantly enrichment particularly Pb than control sites.

Dalbergia sissoo Roxb. is one of the most important timber species of India. It is used for high quality furniture, cabinets making and has pesticidal property. It is commonly planted tree species in urban and suburban areas, roadsides and industrial areas where the soil may be polluted with heavy metals such as Co or Pb. Lead (Pb) and Cobalt (Co) are one of the non essential and toxic heavy metals which can cause oxidative stress in plants. The concentrations of these heavy metals in the environment are currently increasing, due mainly to anthropogenic activities. The effect of these heavy metals on biochemical parameters and antioxidant activity were studied in leaves of Dalbergia sissoo Roxb. grown under control laboratory conditions in pot culture and four levels of heavy metal stress (10, 20, 30 and 40ppm Pb2+, Co2+). Six months exposure of Dalbergia sissoo Roxb. plantlets to different concentration of Co or Pb in normal soil conditions elicited an antioxidative response, measured in terms of ascorbic acid, proline accumulation and biochemical responses in terms of protein and free amino acids. The results indicate that the proline, ascorbic acid contents increased with increase in Co and Pb amount in soil whereas the protein and total chlorophyll contents showed opposite trend.

To evaluate the ambient air quality of the Dehradun city, respirable particulate matter was collected using respirable dust sampler (RDS) and analysed for the heavy metal content using atomic absorption spectroscopy (AAS). The morphology of particulates were determined using scanning electron microscope (SEM) and the elemental composition was determined through SEM- energy dispersive spectroscopy (EDS). Particulate matter mass concentration ranged from 65.00 µg m-3 to 337.33 µg m-3. Quantified heavy metals in particulate matter were Copper (Cu), Zinc (Zn), Cobalt (Co), Manganese (Mn), Iron (Fe), Nickel (Ni), Chromium (Cr), Lead (Pb) and Cadmium (Cd). The order of concentration of heavy metals were found to be in the trend of Fe>Zn>Cu>Pb>Cr>Ni>Mn>Co>Cd. Maximum concentration of PM10 was found at commercial site during summer, winter and monsoon season. Enrichment factor analysis showed substantial contribution of anthropogenic activities on PM10. Source apportionment (varimax rotated factor analysis method) showed dominance of incineration and uncontrolled burning of waste and refuses, resuspended dust with vehicular emission and crustal sources as the dominant sources in Dehradun. Plantation drive strategy have major role in ambient particulate matter mitigation measures and carbon sequestration from climate change and global problem worldwide. This study will be help to mitigate or decrease the load of air pollution by the using of various trees for sustainable human development on the marvellous earth planet.