Ecological Niches

Most angiosperms can be split into three different categories depending on their ecological niches and the availability of water in their habitats. Each group lives in drastically different conditions to the others due to climate and availability of water. All three plant groups have numerous adaptations, that allow them to live in their different environments. With each environment come limitations, but because of the plant's adaptations, they are able to live successfully with these limitations. 

Hydrophytes live in conditions where water is plentiful such as swamps, ponds, streams and lakes.  Some hydrophytes have leaves on the surface of the water while others are completely submerged. The limitation hydrophytes face is the huge quantity of water they are exposed to. Therefore, hydrophytes have minimal adaptations specific to conserving water as they are often surrounded by it. Instead, their adaptations specialise in allowing them to survive in their aquatic environments and enabling the movement of water through the plant. Hydrophytes have adaptations that help eliminate competition with other plants so that lack of other resources don’t become limiting factors to processes such as photosynthesis.

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Mesophyte plants live in environments like those experienced in New Zealand; where there aren’t extreme climate conditions. As mesophytes aren’t exposed to extremely wet or dry conditions, water loss is only a major problem during the hotter time periods such as midday in summer. There isn’t much competition with other plants as far as water is concerned, as there are ample water supplies.

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Xerophytes live in dry, arid conditions such as deserts. The obvious limitation of this environment is the lack of water. Xerophytes are often exposed to extreme heat, cold and wind, making water preservation one of their key focuses. They have adaptations that allow them to gather and store water. It is because of these adaptations that xerophytes are able to survive in their environments. There is a large amount of competition for water as rainfall is minimal. Consequently, most xerophytes’ adaptations are specific to retaining moisture and protecting their water supplies.

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