Revisiting decomposition theory through a macro-detritivore lens.

Area of Science:

• Ecology
• Soil Science
• Biogeochemistry

Background:

• Current decomposition models primarily focus on microbial decomposers and environmental factors like climate and substrate quality.
• These models often overlook the role of larger organisms in nutrient cycling.
• Mesic environments dominate current research, potentially limiting the generalizability of findings.

Purpose of the Study:

• To challenge the established paradigm of terrestrial decomposition.
• To highlight the crucial, yet often underestimated, role of macrofaunal detritivores in decomposition processes.
• To propose the integration of macro-detritivores into ecological theory for a more complete understanding of elemental cycling.

Main Methods:

• The study presents a theoretical argument, synthesizing existing knowledge on macrofaunal detritivore characteristics and functions.
• It contrasts the capabilities of macro-detritivores with those of micro-organisms in decomposition.
• It discusses the mechanisms by which macro-detritivores influence decomposition rates and nutrient availability.

Main Results:

• Macrofaunal detritivores mitigate the strong regulation of decomposition by substrate quality and climate.
• Their traits (size, desiccation tolerance, mobility, nutrition) enable decomposition when microbial activity is limited.
• Macro-detritivores enhance microbial decomposition by fragmenting and translocating detritus to favorable microhabitats.

Conclusions:

• Incorporating macro-detritivores into decomposition theory is essential for a comprehensive understanding of elemental cycling.
• Macro-detritivores play a vital role in nutrient cycling, particularly in environments facing climate change.
• Future research should focus on the understudied contributions of macro-detritivores to ecosystem processes, especially in a warmer and drier world.