The Chemotactic Behavior of Microorganisms Plays a Critical Role in the Spatial Regulation of Carbon Emission Hotspots

Abstract

The global carbon cycle is fundamentally a biological achievement of spatial organization, yet conventional soil carbon models frequently overlook the active role of microbial motility by assuming spatial homogeneity. This review challenges that assumption by elucidating the impact of bacterial chemotaxis—mediated by the Che A/Che Y signal transduction pathway—on the formation of metabolic hotspots. We demonstrate how microorganisms navigate tortuous pore networks to sense chemical fingerprints (e.g., root exudates), generating micrometer-scale zones where metabolic activity increases by two to three orders of magnitude. The physical disruption of this spatial order, particularly through tillage, leads to a profound "decoupling" of the carbon cycle, evidenced by a 27%–34% reduction in soil respiration and a loss of carbon sink capacity. By integrating molecular ecology with microscale process dynamics, we propose a novel framework that elucidates the cascade mechanism extending from chemical fingerprint recognition to community self-organization, and ultimately to carbon flux regulation." This approach links chemotactic protein signaling to gas diffusion processes, offering a robust theoretical foundation for the precise regulation of soil carbon sinks in the pursuit of carbon neutrality.