Arizona State University (ASU) BIO320 Fundamentals of Ecology Exam 3 Practice

Higher lignin concentrations are typically not relevant to increasing rates of nutrient decay because lignin is a complex organic polymer found in the cell walls of plants. It is known for its structural role and makes plant materials more resistant to decomposition. Lignin’s stable structure presents a challenge for decomposers such as fungi and bacteria, which find it difficult to break down. As a result, environments with high lignin levels experience slower rates of nutrient decay.

In contrast, increased moisture levels enhance microbial activity and promote decomposition by allowing decomposers to thrive. Higher bacterial populations directly contribute to the breakdown of organic materials, leading to faster nutrient cycling. Higher carbon concentrations in organic matter provide an essential energy source that supports the microbial community responsible for decomposition. All these factors facilitate more rapid nutrient decay, making them relevant in this context, unlike lignin, which slows down the process.