species for green belts with respect to its ecological identity, soil specifications, method of its cultivation, use of special chemicals and pigments to give extra strength to the species to grow in not-so-favourable environment. Not all types of plants are suitable for mitigation of the air pollution. There have been several studies in India since 1972 on the survey and assessment of different plant species for their tolerance to air pollution under field and laboratory conditions. Based on these studies assortment of several plant species have been done for the green belts of specific purposes and presented herewith.

Table 3 : Plant species suitable for growing along roadside with heavy vehicular traffic

Sr. No.	Botanical Name	Habit	Location of Plantation
1.	Eucalyptus Sp.	Tree	Road side
2.	Polyalthia longifolia	-do-	-do-
3.	Syzygium Jambolana	-do-	-do-
4.	Casia fistula	-do-	-do-
5.	Mangifera indica	-do-	-do-
6.	Alstonia scholaris	Shrub	Road divider channel
7.	Nerium indicum	-do-	Road side too
8.	Bougainvillea spectabilis	-do-	-do-
9.	Duranta Plumieri	-do-	-do-
10.	Cynodon dactylon	Herb	Traffic island, Parks

PROTECTION OF PLANTS AGAINST AIR POLLUTION

Soil
A pit of 3 x 3 x 3 ft. should be dug and be filled with soil and farm yard manure in the ratio 1:1.

Age
The age of the plant species for plantation in green belts should be as high as practicable because young plants are more vulnerable to air pollution damage even lower. Generally the height of the tree sapling should be 3 - 5 feet.

Watering
The watering of the plants must be done at least once or twice in a day to maintain its water content. More water in plant body help to maintain the physiological balance under stress conditions of air pollution when the transpiration rates are usually high. The water level in plant body is especially vital for maintaining the ionic balance of cell sap because many gaseous pollutents lower the PH of cell sap on entering in the leaf through stomate thereby adversely affecting the growth and productivity of the plant. Water stress in plants also reduce their dust capturing capacity.

Table 4 : Plant species suitable for growing in premises of industries

Sr. No.	Botanical Name	Habit	Pollutant Target
1.	Eucalyptus Sp.	Tree	Gases
2.	Leucaena leucocephala	-do-	-do-
3.	Polyalthia pendulosa	-do-	-do-
4.	Casia fistula	-do-	-do-
5.	Syzygium jambolana	-do-	-do-
6.	Tectona grandis	-do-	Dust
7.	Shorea robusta	-do-	-do-
8.	Polyalthia longifolia	-do-	-do-
9.	Mangifera indica	-do-	-do-
10.	Anthocephalus cadamba	-do-	-do-
11.	Bougainvillea spectabilis	Shrub	Dust & gases
12.	Alstonia scholoris	-do-	-do-
13.	Murraya exotica	-do-	-do-
14.	Nerium odoratum	-do-	-do-
15.	Cynodon dactylon	Herb	Dust + gases

Table 5 : Plant species suitable for growing around Sewage Treatment Plants

Sr. No.	Botanical Name	Habit
1.	Leucaena leucocephala	Evergreen Trees
2.	Eucalyptus rostrata	-do-
3.	Alstonia scholoris	-do-
4.	Ficus glomerate	-do-
5.	Pithecelobium dulca	-do-
6.	Ricinus communis	Shrub
7.	Calotropis Sp.	-do-
8.	Poinsettia Pulcherima	-do-
9.	Rosa indica	-do-
10.	Duranta plumieri	-do-
11.	Vinca rosea	Herb
12.	Croton tiglium	-do-
13.	Ocimum basilicum	-do-
14.	Cynodon dactylon	-do-
15.	Ageratum conyzoides	-do-