Question 76
Explain the importance of soil for plant growth.
Soil supports plant growth by providing:
a) Anchorage: Root systems extend outward or downward through the soil, thereby stabilising plants.
b) Oxygen: The spaces among soil particles contain air that provides oxygen, which living cells (including root cells) used to break down sugars and release the energy need to live and grow.
c) Water: The spaces among soil particles also contains water, which moves upward through plants. This water cools plants as it evaporates off the leaves and other tissues, carries essential nutrients into plants, helps to maintain cell size so that plants don’t wilt and serves as a raw material in the process of photosynthesis, the process by which plants capture light energy and store it in the form of sugars for later use.
d) Temperature modification: Soil insulates roots from drastic fluctuations in temperature. This is especially important during excessively hot or cold times of the year.
e) Nutrients: Soil supplies nutrients and also holds the nutrients that we add in the form of fertilizer.