Tag: protecting our environment

A halophyte is a plant, that grows in waters of high salinity, coming into contact with saline water through its roots or by salt spray, such as in saline semi-deserts, mangrove swamps, marshes and sloughs, and seashores.

These specialized aerial roots enable plants to breathe air in habitats that have waterlogged soil. The roots may grow down from the stem, or up from typical roots. The surface of these roots are covered with lenticels which take up air into spongy tissue which in turn uses osmotic pathways to spread oxygen throughout the plant as needed. 

Pneumatophores are specialized root structures, that grow out from the water surface and facilitate the aeration, necessary for root respiration, present in mangroves like Rhizophora. 

The soil in coastal region is poorly aerated and it contains very small percentage of oxygen, because of waterlogging. Under such conditions, the roots of halophytes do not get sufficient aeration. In order to compensate this lack of soil aeration, the hydro-halophytes develop special type of negatively geotropic roots, called as pneumatophores or breathing roots. The pneumatophores usually develop from the underground roots and project in the air well above the surface of mud and water. They appear as peg-like structures. The tips of these respiratory roots may be pointed. They possess numerous lenticels or pneumathodes on their surface and prominent aerenchyma enclosing large air cavities internally. The gaseous exchange takes place in these roots through the lenticels.

Mangroves are marshy area found in tropical deltas and saline ponds near seashores. The area have not only excess salt but also excess water of anaerobic conditions besides difficulty in  anchoring and seed germination. Plants growing in mangroves are halophytes. Such forests are found in West Bengal in India. Mangroves of West Bengal are called Sunderbans.

Halophytes are plants of saline habitats, which have the ability to tolerate high salt content. They are able to obtain water supply inspite of high salt content in soil. They grow in saline soil, e.g., mangroves.

Halophytes grow in soil which is physiologically dry. The soil is having lots of salts, hence, halophyte plants have devised various adaptations to absorb water. A green halophytic alga Dunaliella, found in hypersaline lakes, accumulates glycerol in its cells to help in osmoregulation.

A number of halophyte plants possess small negatively geotropic vertical roots, called as pneumatophores. Pneumatophores have lenticels for gaseous exchange. They are connected with internal aerenchymatous tissue.

Rhizophora is a well-known genus of mangrove trees that grow in intertidal zones and are adapted to saline conditions.

A rhizophore is a specialized organ found in plants like Selaginella that acts as an intermediate structure, exhibiting characteristics of both roots and stems.