Forest Ecology

Forest Ecology

Many different schemes to classify tropical forest types are based on various criteria including climate, soil, species composition, structure, function and successional stage. Included Evergreen tropical forests (including rain forests), Seasonal tropical forests, Dry tropical forests, and Tropical forests on mountains.

Forest Regeneration

Forest restoration is all about accelerating natural forest succession, so its success depends on understanding and enhancing the natural mechanisms of forest succession. Succession is a series of predictable changes in ecosystem structure and composition that occurs after disturbance. If allowed to run its course, succession eventually results in a final, climax ecosystem with maximum biomass, structural complexity and biodiversity within the limitations imposed by the local soil and climatic conditions.

A climax tropical forest is not a stable unchanging system but rather a dynamic equilibrium undergoing constant disturbances and renewal. Gaps are formed when large trees die, but they are rapidly filled as saplings and seedlings grow up to exploit the light.

Understanding forest succession is essential for designing effective forest restoration methods. Forest restoration seeks to remove those factors that prevent natural forest succession from progressing.

Regeneration in Large Deforested Areas

The establishment of forest trees usually depends on the availability of local seed sources and the dispersal of seeds into deforested sites. Seeds must land where conditions are suitable for germination and they must escape the attention of seed-eating animals, the so called ‘seed predators’. After germination, tree seedlings must win an intense competition with weeds for light, moisture and nutrients. Growing trees must also avoid being burnt by wildfires or eaten by cattle.

Succession proceeds rapidly in tree-fall gaps within intact forest. (A) Nearby fruiting trees provide (B) a dense seed rain. The surrounding forest provides habitat for (C) seed-dispersing animals. (D) Damaged trees and (E) tree stumps re-grow. (F) Seedlings and (G) saplings, which were formerly suppressed by the dense forest canopy, now grow rapidly. (H) Seeds in the soil seed bank germinate. In large deforested areas, many of these natural mechanisms of forest regeneration are reduced or blocked entirely by human activities.