Consider the following statements : 1. Different plant species grow together. 2. Light cannot penetrate into the lower strata full of undergrowth. Which of the following types of vegetation is characterized by the above?

The characteristics described—diverse plant species growing together and restricted light penetration to the lower strata—are defining features of the Equatorial moist evergreen forest (Tropical Rainforest). These forests are characterized by a 'multitude of evergreen trees' and a 'great variety of vegetation' including lianas, epiphytes, and parasites [1]. The structure is vertically stratified with a dense, multi-layered canopy [3]. This thick canopy of foliage is so complete that it 'cuts out most of the sunlight,' preventing it from reaching the lower layers [2]. Consequently, less than 1% of light strikes the forest floor, making light a major limiting factor for undergrowth. While the understory contains shade-tolerant species, the lack of light penetration generally results in sparse ground vegetation in primary forests unless a 'light gap' is created by a fallen tree [3].

Sources

1. [1] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 15: The Hot, Wet Equatorial Climate > Natural Vegetation > p. 152
2. [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 30: Climatic Regions > Equatorial Vegetation > p. 426
3. [2] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 3: Terrestrial Ecosystems > 3.2.5. Tropical rain forests: > p. 25