Plant growth and decomposition are constrained by the comparatively small amount of light and heat and by the very short but intense growing season. These limiting factors affect the ability of wildlife and plants to reproduce successfully and to maintain their populations over time. The following activities demonstrate the effects of temperature and freezing on decomposition and the effect of permafrost on plant growth. The honeycomb polygonal shape is the result of the seasonal churning of the ground above the underlying layer of permafrost. Temperature and Decomposition D ecomposers are a crucial link in food chains and food webs because they return to the soil organic compounds that enhance plant growth.
Decomposition is slower in the far North than in the rest of North America.
Because decomposing matter takes longer to become integrated into the soil, plant growth may be limited by the lack of organic compounds in the soil. The slow process of soil formation in cool climates means that existing soil is slow to recover from disturbance by humans, animals, or the forces of erosion. Have students try the following activity to help them understand the effect of cool temperatures on decomposition. Prior to the investigation, record students' hypotheses about how temperature relates to decomposition. Keep the light conditions reasonably similar in each environment.