Monday, December 14, 2009


These are plants which grow in or near water and are adapted according to whether they live on the surface, or are submerged, or grow in the mud at the edge of the water.Some are a combination of all these and have several different types of leaves. Some hydrophytes (for example water lily) are anchored to the bottom by roots, and send up leaves on long stems until they reach the surface, when they unfold and spread out. The giant water lily (Victoria regia) is an extreme example of this. The flowers too come up on a long stem and open out above the water.

Some water plants are not rooted to the bottom and merely float on the surface (for example duckweed) or under the surface (for example bladderwort). Such water plants can only live in still waters but some submerged plants are anchored to the bottom by roots and produce long growth with small leaves and these are better adapted to life in running water. The leaves of most water plants have large air cavities in them to act as ‘water wings’, and some produce large bladder-like swellings for the same purpose(for example water hyacinth).

The water crowfoot is amphibious, that is it can live both in water and at the edge in the damp mud. It has surface leaves which are flat and large compared to the submerged leaves which, when living in water, are finely divided with narrow lobes. These smaller leaves disappear if the water level drops and the plants are left at the edge.

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