Q. The sequence of communities of primary succession in water is
Solution:
In aquatic habitat like freshly formed pond the succession is hydrosere. From hydric to mesic condition the successional series progress.
(i) Pioneer Community : Phytoplanktons i.e. the minute microscopic autotrophic organisms like diatoms, unicellular, colonial or filamentous green algae and blue -green algae makes pioneer community. Through wind or animals in the newly formed pond the spores of these phytoplankton organism reaches. As they multiply rapidly, it becomes a suitable habitat for the zooplankton which feed upon them. With the clay and slit at the bottom of the pond the organic matter formed by the death and decay of plankton mixes and it forms soft mud. This makes the habitat suitable for the growth of next stage.
(ii) Transitional Communities : (a) Submerged plant stage : At the bottom of the water body in the mud this plant are anchored with the help of their roots. e.g., Myriophyllum, Hydrilla, Vallisneria, Potamogeton etc. (b) Submerged free-floating plant stage : The bottom level is raised as well as ponds become rich in minerals (nutrients) due to the accumulation of dead and decaying remains of submerged plant, which becomes suitable for free-floating plants, e.g., Azolla, Wolfia, Pistia etc. (c) Reed-swamp stage : Due to continuous siltation more shallowing of plant occurs which paves way for the growth of rooted emergent plant i.e. reeds (amphibious plants). e.g., Typha, Sagittaria, Phragmites etc. (d) Marsh-meadow stage : The marshy plants invades reed-swamp stage. With increased settling of silt and deposition of dead organic matter derived from floating and rooted species, the shallowing of pond occurs until it gets transformed into terrestrial habitat. e.g., Carex, Juncas, Cyperus. (e) Scrub stage : Shrubs replaces marsh-meadow stage. e.g., Salix, Populus, Alnus. (iii) Climax Community : The trees replaces the scrub stage and it grows up to greater heights the nature of climax community depends on the climate of that area. e.g., Forest.
Thus, the sequence of communities of primary succession in water is as follows:- phytoplankton rooted submerged hydrophytes floating hydrophytes reed swamp sedges meadow trees (Forest).
(i) Pioneer Community : Phytoplanktons i.e. the minute microscopic autotrophic organisms like diatoms, unicellular, colonial or filamentous green algae and blue -green algae makes pioneer community. Through wind or animals in the newly formed pond the spores of these phytoplankton organism reaches. As they multiply rapidly, it becomes a suitable habitat for the zooplankton which feed upon them. With the clay and slit at the bottom of the pond the organic matter formed by the death and decay of plankton mixes and it forms soft mud. This makes the habitat suitable for the growth of next stage.
Thus, the sequence of communities of primary succession in water is as follows:- phytoplankton rooted submerged hydrophytes floating hydrophytes reed swamp sedges meadow trees (Forest).