Assessing soil microbial catabolic diversity in alder and oak plantations at varying developmental stages

1410-1424

Artikel aus einer Zeitschrifte-journal

200212196

Canadian Journal of Forest Research 2024, 54(12) ; Jrg. 54 ; 12 (2024) , 1410-1424

To evaluate the impact of forest plantations on soil microbial catabolic diversity, this study investigated the microbial response to the addition of various carbon-rich substrates in different ages of forest plantations and compared catabolic diversity between a nitrogen-fixing tree species (Alder, Alnus subcordata C. A. M.) and a non-nitrogen-fixing one (Oak, Quercus castaneifolia C. A. M.). The study also analyzed the effects of carbon substrates found in association with roots, such as carbohydrates, carboxylic acids, amino acids, and amine groups, on substrate-induced respiration. The diversity indices (Simpson and Shannon diversity indicies) and Shannon evenness index demonstrated higher values in the oldest plantations than the youngest ones (with an order of 25 > 20 > 15 years). In younger plantations (15 and 20 years old), oak stands exhibited highermicrobial diversity compared to alder stands. However, at 25 years old, alder plantation displayed greater diversity than the oak plantation, as indicated by higher values for the Shannon diversity index (2.77), Simpson diversity index (0.93), and Shannon evenness index (0.89). Forest plantations with alder and oak species significantly enhanced catabolic evenness and diversity, thereby increasing the soil capacity to decompose organic matter and the resilience of the soil to disturbance. These findings suggest that both alder and oak plantations can promote soil microbial diversity, but the influence might differ depending on the specific age of the trees. In conclusion, this study highlights the influence of forest plantations on soil microbial catabolic diversity, demonstrating the potential of diverse tree species to promote soil health and resilience through enhanced functional complexity.
Keywords: microbial community, diversity indices, carbon substrate, Hyrcanian region, topsoil