Abramoff, R. | Search bioRxiv

bioRxiv2023

Contribution of carbon inputs to soil carbon accumulation cannot be neglected

In a recently published paper (1), the authors report that microbial carbon use efficiency (CUE) is the primary determinant of global soil organic carbon (SOC) storage and that the relative impact of plant carbon inputs on SOC is minor. While soil microbes undoubtedly play an important role in soil organic carbon cycling, we are concerned about the robustness of the approach taken by Tao et al. (1) and highlight potential biases in their analyses that may lead to misleading, model-dependent results.

ecology↗

bioRxiv2020

A global map of root biomass across the world's forests

Abstract (150 words limits)Root plays a key role in plant growth and functioning. Here we combine 10307 field measurements of forest root biomass worldwide with global observations of forest structure, climatic conditions, topography, land management and soil characteristics to derive a spatially-explicit global high-resolution (~ 1km) root biomass dataset, including fine and coarse roots. In total, 142 {+/-} 32 Pg of live dry matter biomass is stored below-ground, that is a global average root:shoot biomass ratio of 0.25 {+/-} 0.10. Our estimations of total root biomass in tropical, temperate and boreal forests are 44-226% smaller than earlier studies1-3. The smaller estimation is attributable to the updated forest area, spatially explicit above-ground biomass density used to predict the patterns of root biomass, new root measurements and upscaling methodology. We show specifically that the root shoot allometry is one underlying driver that leads to methodological overestimation of root biomass in previous estimations.

ecology↗