In the grasslands, trees do not replace the grasses as a part of an ec

In the grasslands, trees do not replace the grasses as a part of an ecological succession because of

insects and fungi
limited sunlight and paucity of nutrients
water limits and fire
None of the above
This question was previously asked in
UPSC IAS – 2013
The correct answer is C) water limits and fire.
In many grassland ecosystems, the primary environmental factors that prevent the establishment and growth of trees, thus maintaining the dominance of grasses in ecological succession, are limited water availability (seasonal droughts, low rainfall) and frequent fires (natural or human-caused). Grasses are well-adapted to these conditions, with deep root systems that survive drought and ability to quickly regrow after fire, whereas young trees are often killed by lack of water or fire.
Ecological succession is the process by which the mix of species and habitat in an area changes over time. In a typical succession sequence in a region capable of supporting forests, grassland might be a transitional stage before shrubland and then forest. However, specific environmental regimes like drought and fire can create “climax communities” like grasslands where forest does not develop. While other factors like grazing can also influence grasslands, water limits and fire are fundamental abiotic factors that often define this biome.