Journal Article

Quantifying wetland plant vertical root distribution for estimating the Interface with the anoxic zone

He, Yuhong, Proctor, Cameron

2019

Overview

Aims Plant roots control many important interactions in the wetland anoxic zone such as carbon deposition, gas exchange, and nutrient dynamics, yet few studies document the vertical depth distribution of fine roots which mediates these interactions. Methods Excavated root systems of a wetland sedge and shrub were scanned. Utilizing Root System Analyzer, normalized root length per 5 cm depth interval were quantified for 10 samples of each species. Utilizing bootstrapping, root length per depth interval for each root class was fitted to a density distribution function and matched to water table depth. Results Vertical root length distributions varied by root class, with shrub fine roots constrained to a narrow depth range. Between 1999 and 2010, the interface with the anoxic zone can vary by a factor of four between wet and dry years. Conclusions Compared to estimates of root vertical distribution based on biomass, this study indicates a considerably higher portion of the fine roots occur in anoxic soil. Accurately quantifying the spatial distribution of the fine roots, root tips, and other sites associated with exudation is crucial for determining the strength of root-methanogen interactions.

• Publisher: Springer Science + Business Media,Springer International Publishing,Springer,Springer Nature B.V
• Subject: biomass / Biomedical and Life Sciences / carbon / Density distribution / Distribution (Probability theory) / Distribution functions / Ecology / Exudation / fine roots / Gas exchange / Life Sciences / Nutrient dynamics / Plant Physiology / Plant roots / Plant Sciences / REGULAR ARTICLE / Root distribution / root systems / root tips / Roots / shrubs / soil / Soil Science & Conservation / Spatial distribution / Vertical distribution / Water depth / Water table / Water table depth / wetland plants / Wetlands