Who explained: "Succession is an extraordinarily mobile phenomenon whose processes are not to be stated as fixed laws, but only as general principles of exceedingly broad nature and whose results need not and frequently do not occur in any definite predictable way"?

Correct option is C

The correct answer is (c) H.A. Gleason (Individualistic Concept). H.A. Gleason proposed the Individualistic Concept of Succession, which argues that ecological succession is not a fixed or predictable process. Instead, it depends on the interactions of individual species, their dispersal patterns, and environmental conditions. This concept suggests that plant communities are not tightly integrated entities but rather a collection of species that happen to coexist due to similar environmental requirements.
Breakdown of Other Options:
· (a) F.E. Clements (Relay Floristics view):
· Proposed the Relay Floristics model, suggesting that succession occurs in a predictable sequence where one group of species prepares the environment for the next.
· (b) F.E. Egler (Initial Floristics Composition view):
· Suggested that most species are present early in succession, and the sequence depends on which species dominate at different times.
· (d) D. Tilman (Resource-ratio hypothesis):
· Focused on the Resource-Ratio Hypothesis, explaining how species composition changes based on competition for limited resources.
Information Booster 1. Clementsian Succession:
· Succession follows a predictable, orderly sequence of stages, leading to a stable climax community.
2. Gleason’s Individualistic Concept:
· Succession is unpredictable and depends on the interactions of individual species and environmental variability.
3. Egler’s Initial Floristics:
· Suggests that all potential species arrive early, and succession depends on differential growth rates.
4. Tilman’s Resource-Ratio Hypothesis:
· Succession is influenced by the relative availability of resources (e.g., light, nutrients).