Question

Identify the correct sequence of the seral stage in hydroseres.
A. Plankton, submerged, floating, red swamp, sedge meadow, woodland
B. Plankton, floating, submerged, red swamp, sedge meadow, woodland
C. Plankton, floating, submerged, sedge meadow, red swamp, woodland
D. Plankton, submerged, floating, sedge meadow, woodland, red swamp

Answer 1

Biological Succession is a series of events that occur on the barren surface that starts with the pioneer community and reaches to the climax community which is a stable community. An algal bloom is excessive growth of algae in a water body, which destroys the water quality and aquatic life.

Complete answer: Series of biotic communities that develop on the recently formed lake or pond is called the hydrosere. It begins when the muddy water becomes clear. The hydrosere type of biological succession consists of various stages.
a) Planktonic sage:- It is a pioneer stage of hydrosere, the spore of this stage reaches to the water body via wind or animal, the first-minute organism which appears is called phytoplankton like diatom, green flagellates and blue-green algae. They soon multiply and are maintained by zooplanktons which feed on phytoplankton. The death of these microbes creates the next seral stages.
b) Submerged stage:- In this stage, the bottom of the lake is lined with soft muddy organic matter which is favourable for a submerged plant like hydrilla, najas, etc. They root in the mud and form a dense growth. This results in sand and silt deposition around the plant. The bottom level rise and the older plant buried creates humus which favours the next seral stages.
c) Floating stage:- Nuphar like plant appears where water is shallow. Such plants have a subterranean stem-like rhizome and tuber. The plant makes the water richer in nutrient and organic matter which is suitable for a free-floating plant-like Lemna , Spirodela , Wolffia and Azolla. They cover the water body.
d) Reed swamp stage is the stage of plants that grow where water becomes shallow. Plants of reed swamp stage transpire huge quantities of water.
e) Sedge meadow:- The shore of the reed swamp stage is invaded by sedge, Juncus and grasses. These plants transpire rapidly and add abundant humus, which favours the next seral stages.
f) Woodland stage:- The periphery of the meadow stage is invaded by some rhizome bearing shrubby plants which can tolerate both sunlight and waterlogged condition. This stage creates a favourable environment for the next climax community.
Hence, the correct option is A.

Note: The succession is of two types: primary and secondary succession. Primary succession occurs on unweathered or new form rock-like deposited lava or new island, while secondary succession occurs on an area that became barren due to the destruction of the previous community.