A History of Agriculture in India v1.c10.s5: 5. The Mangrove and Beach Forests
A History of Agriculture in India v1.c10.s5
- Language
- English
5. The Mangrove and Beach Forests
v1.c10.s5.1
Throughout the tropics, particularly in the littoral regions in the estuaries of rivers, in creeks and lagoons of low-lying areas, is to be found a peculiar type of vegetation known as the mangrove vegetation or the mangrove swamp. In India and Pakistan, the mangrove forests are developed in suitable localities along the coastal region, from the Indus Delta in Sind southwards, along the West Coast of Peninsular India down to Kerala, and from the Sunderbans southwards along the East Coast of the Peninsula. They are also seen along the coast of the Andamans and the adjacent islands. The mangrove formations extend up rivers, sometimes for miles.
v1.c10.s5.2
The more common families represented in our typical mangrove forests are Rhizophoraceae, Meliaceae, Leguminosae, Combretaceae, Lythraceae, Rubiaceae, Myrsinaceae, Acanthaceae, Verbenaceae, Euphorbiaceae and Palmaceae.
v1.c10.s5.3
The following are some of the species met with in the mangrove forests of India and the Andamans: *Rhizophora mucronata*, *R. apiculata* (*R. conjugata*), *Ceriops tagal* (*C. candolleana*), *C. roxburghiana*, *Kandelia candel*, *Bruguiera conjugata* (*B. gymnorhiza*), *B. sexangula* (*B. eriopetala*), *B. cylindrica* (*B. caryophylloides*), *Xylocarpus granatum*, *Cynometra ramiflora*, *Aegialites rotundifolia*, *Xylocarpus molluccensis*, *Lumnitzera racemosa*, *L. littorea* (*L. coccinea*), *Sonneratia apetala*, *S. alba*, *S. caseolaris* (*S. acida*) *Scyphiphoya hydrophyllaceae*, *Aegiceras corniculatum*, *Acanthus ilicifolius*, *Avicennia officinalis*, *Excoecaria agallocha*, *Nipa fruticans* and *Phoenix paludosa*.
v1.c10.s5.4
As regards the distribution of the species in our mangrove forests, along the East and West Coasts of India and the Sunderbans and the Andamans, it is seen that whereas some species such as *Rhizophora mucronata*, *Bruguiera conjugata* (*B. gymnorhiza*), *Sonneratia caseolaris* (*S. acida*) and *Aegiceras corniculatum* are common to all these areas, a few others have rather a restricted distribution on the East Coast of Peninsular India and in regions east of it. Among this category may be mentioned *Xylocarpa molluccensis* *Scyphiphora hydrophyllaceae*, *Nipa fruticans* and *Phoenix paludosa*.
v1.c10.s5.5
One of the most extensively developed mangrove forests in India is in the Sunderbans in the Ganges Delta. In this forest belt, there are about 50 species of trees which may be conveniently classified into: (1) purely estuarial species, and (2) species common to other parts of India. Among the purely estuarial species are: *Hibiscus tiliaceus* (*H. tortuosus*), *Thespesia populnea*, *Brownlowia lanceolata*, *Amoora cucullata*, *Xylocarpus molluccensis*, *X. granatum*, *Bouea burmanica* (*B. oppositifolia*), *Erythrina variegata*, *Afzelia bijuga*, *Rhizophora apiculata* (*R. conjugata*), *R. mucronata*, *Ceriops roxburghiana*, *Kandelia candel*, *Bruguiera conjugata* (*B. gymnorhiza*), *B. parviflora*, *Lumnitzera racemosa*, *Barringtonia racemosa*, *Sonneratia apetala*, *S. caseolaris* (*S. acida*), *Aegialites rotundifolia*, *Aegiceras corniculatum*, *Cerbera odollam*, *Avicennia officinalis*, *A. alba*, *Excoecaria agallocha*, *Sapium indicum*, *Casuarina equisetifolia*, *Nipa fruticans* and *Phoenix paludosa*. To these may also be added *Hibiscus tiliaceous*, *Dalbergia spinosa*, *D. candenatensis* (*D. torta*), *Mucuna gigantea*, *Derrisinuata* and *D. trifoliata* (*D. uliginosa*), *Finlaysonia obovata*, *Sarcolobus globosus*, *Acanthus ilicifolius* and *A. volubilis*.
v1.c10.s5.6
Of the species common to inland Bengal, the following may be mentioned: *Kleinhovia hospita*, *Micromolum pubescens*, *Aegle marmelos*, *Ziziphus mauritiana* (*Z. jujuba*), *Lannea coromandelica*, *Cassia fistula*, *Pongamia pinnata*, *Acacia tomentosa*, *A. nilotica* (*A. arabica*), *Barringtonia acutangula*, *Ixora arborea* (*I. parviflora*), *Morinda bracteata*, *Diospyros montana*, *D. peregrina* (*D. malabarica*), *Cordia dichotoma* (*G. myxa*), *Dolichandrone spathacea* (*D. rheedii*), *Vitex trifolia*, *V. negundo*, *Drypetes assamica* (*Cyclostemon assamicus*), *Croton oblongifolius*, *Antidesma ghaesembilla*, *Trewia nudiflora*, *Streblus*, *Trema* and *Ficus*.
v1.c10.s5.7
The root-system of mangroves is characterized by special adaptations to their environments, which are often water-logged and poorly aerated. Some species as *Rhizophora* have a system of aerial stilt roots to support the trees; others, e.g. *Bruguiera*, send up peg-like projections from their roots; still others, e.g. *Heritiera*, *Lumnitzera* and *Kandelia*, produce aerial ‘knee roots’; and yet others, e.g. *Avicennia*, have pneumatophores or breathing roots. In the Sunderbans are found ‘pure sundri’ forest (*Heritiera minor*, *H. fomes*) with dense pneumatophore growth (Fig. 16).
v1.c10.s5.8
The members of Rhizophoraceae exhibit a peculiar phenomenon known as vivipary. Owing to this phenomenon, while the fruit is still attached to the parent tree, the embryo begins to grow, the hypocotyl protrudes, and the scedling hangs vertically from the fruit itself.
v1.c10.s5.9
Beach Forests. Before concluding this chapter, a brief mention may also be made of a narrow belt or strip of vegetation seen along the coast, and a little farther from the high-tide limits, known as the beach forests. In this belt, the trees are partly evergreen and partly deciduous. In places, *Casuarina equisetifolia* is cultivated extensively.
v1.c10.s5.10
Among the more common species may be mentioned: *Mimusops littoralis*, *Pongamia pinnata*, *Morinda citrifolia*, *Erythrina variegata*, *Calophyllum inophyllum*, *Terminalia catappa*, *Barringtonia asiatica* (*B. speciosa*), *Cordia subcordata*, *Thespesia populnea*, *Vigna marina* (*V. retusa*), *Mucuna gigantea*, *Colubrina asiatica*, *Calotropis gigantea* and *Pandanus odoratissimus* (*P. tectorius*).