What is van mahotsava? What is its social impact?

Van mahotsava is a tree plantation drive undertaken by both government and non-government agencies including schools and colleges. It is performed twice a year during July and February when the climate is favorable and the soil has sufficient moisture. Tree plantation drive not only replaces the trees felled during development but also add to the number already existing. It shall
(i) Keep the air cleaner by removal of dust and pollutants.
(ii) Add to the oxygen content of the air.
(iii) Reduction in $C{O}_2$ content.
(iv) Reduction in noise by acting as green muffler.
(v) Moderating climate.
(vi) Bringing us near to nature as trees will invite a number of small animals to take shelter.
(vii) Inculcation of the spirit of comradeship and service to nation as well as nature.