Introduction to Forests, roots and soil carbon

Below-ground components including roots are key contributors to the total forest ecosystem biomass and productivity.

Prescott, C.; Addo-Danso, S. D.; Godbold, D. L.

2016

English

Below-ground components including roots are key contributors to the total forest ecosystem biomass and productivity. Usually neglected in ecological studies, roots (and their microbial associates) are now recognized as key determinants of carbon sequestration in forest soils. They influence pools and fluxes of soil C through production of recalcitrant organic matter, slow or incomplete decomposition, aggregate formation, and priming of organic matter decay through release of C-rich exudates. These important roles make roots disproportionately important to the global carbon cycling, yet they remained largely under-studied until recently. Exploring these forests components, and their roles have been partly hindered by concerns about the reliability and accuracy of available tools and approaches. New insights have however arisen from recent application of functional trait analysis and root-order determination, and novel techniques such as nuclear magnetic resonance spectroscopy of organic matter and stable-isotope probing of C fluxes through soil food webs. Methods to increase efficiency of root biomass estimation and production have also improved, as has our understanding of root turnover and its relationship with site, species and climate. Recognition of the recent rapid advances in this field led to the proposal for a session on this topic at the XXIV World Congress of the International Union of Forest Research Organizations (IUFRO) held in Salt Lake City, Utah, USA, 5–11 October, 2014. The objectives of the sessions were to: (1) provide insights into new tools and approaches to quantify forest ecosystem root-carbon dynamics; and (2) improve understanding of the contribution of roots to soil carbon, and their linkages to forest management, climate change and ecosystem services. Ten oral presentations and 17 poster presentations were made on these topics during the double session, which was complemented with lively discussion. Authors were invited to submit manuscripts for this special issue of Forest Ecology and Management, and the resulting papers appear in the following pages. We thank the authors, the conference presenters and the peer reviewers for their valuable contributions to this special section.