Question

For the following aspects, choose if biodiversity increases, decreases or does not affect it:
$\begin{array}{cc}ColumnI& ColumnII\\ \left(i\right)Soilerosion& \left(r\right)Decreases\\ \left(ii\right)Globalwarming& \left(q\right)Increases\\ \left(iii\right)Nutrientrecycling& \left(s\right)Doesnotaffect\\ \left(iv\right)Pollination& \\ \left(v\right)Biologicalcontrol& \end{array}$

• A. (i) - s, (ii) - q, (iii) - q, (iv) - r, (v) - s
• B. (i) - r, (ii) - q, (iii) - q, (iv) - r, (v) - r
• C. (i) - r, (ii) - r, (iii) - q, (iv) - q, (v) - q
• D. (i) - q, (ii) - s, (iii) - q, (iv) - r, (v) - s
• E. (i) - r, (ii) - s, (iii) - r, (iv) - q, (v) - q

Answer 1

The correct option is C (i) - r, (ii) - r, (iii) - q, (iv) - q, (v) - q

A high degree of biodiversity gives rise to a range of plant types that have unique properties. There is a higher likelihood of the emergence of plants that have strong roots that anchor the giant trees firmly in the soil. This in turn keeps the soil in place and reduces the risk of soil erosion. Biodiversity also indirectly reduces soil erosion by enabling trees with large trunks to act as windbreakers and hence, reduce the action of wind on soil erosion. Biodiversity also enables the emergence of accessory plants like creepers, shrubs and herbs and together, the highly diverse ecosystem sequesters carbon dioxide - a greenhouse gas and thereby reduces global warming. The presence of a diverse range of plant species enables many animals and birds to take shelter and reside in these plants. The excreta of these animals along with the dead remains of plants and animals forms rich fodder for detritivores to feed on and release essential nutrients back into the system thereby increasing nutrient cycling. Biodiversity also increases the presence of pollinators like bees and birds which in turn, enable intermixing of genes to ensure a healthy heterogenous genetic population, which further increases biodiversity. Some animals, especially birds, bats and insects are also often the natural enemies of weeds, pests and diseases that can harm crops and act as effective biological control agents. Therefore, biodiversity reduces soil erosion and global warming while it increases nutrient cycling, pollination and biological control.