Bog Plants
A type of physiologically dry habitat is the bog. There is abundance of water but lake of drainage makes the soil water- logged. The soil is not aerated. Anaerobic bacteria thrive. This leads to an accumulation of carbon dioxide and organic acids in the soil. Some of the products of bacterial metabolism are toxic to the roots. The water also becomes acidic. Under these conditions, absorption of water by the roots is very difficult. The plants, therefore, show marked xerophytic characters. The special features of the bog plants are the large intercellular spaces which form a well-drained system of air cavities in their roots. These communicate with similar cavities in the stem and leaf-stalks. Oxygen formed during photosynthesis is forced down towards the roots and there it is used for respiration.
No comments:
Post a Comment