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What will be the $P / R$ ratio of a climax community and a pioneer community? What explanation could you offer for the changes seen in $\mathrm{P} / \mathrm{R}$ ratio of a pioneer community and the climax community?
Explanation
Production/Respiration ratio ( $\mathrm{P} / \mathrm{R}$ ) ratio It shows the relationship between gross production and total community respiration where $\mathrm{P} / \mathrm{R}=1$ a steady state community result.
This result may be instantaneously daily one or over a longer period. If $P / R$ is persistantly greater or less than/then organic matter either accumulates or is depleted respectively.
| Pioneer Community | Climax Community |
|---|---|
| The species that invade a base area are called pioneer species on base rockes these are generally lichens. | It is a final biotic community that develops in an area. |
| In aquatic ecosystem there are phytoplanktons. | It occurs over an area previously occupied by several communities. |
| In pioneer community the $P / R$ ratio will be more than one. | In climax community the P/R ratio will be 1 . |