Inner bark vs sapwood is the main driver of nitrogen and phosphorus allocation in stems and roots across three tropical woody plant communities

Abstract

Summary Nutrient allocation is central to understanding plant ecological strategies and forest roles in biogeochemical cycles. Thought to be mainly driven by environmental conditions, nutrient allocation to woody organs, especially to living tissues, is poorly understood. To examine the role of differences in living tissues (sapwood, SW, vs inner bark, IB), organs, ecological strategies, and environmental conditions in driving nutrient allocation and scaling in woody plants, we quantified nitrogen and phosphorus in main stems and coarse roots of 45 species from three tropical ecosystems with contrasting precipitation, fire regime, and soil nutrients. Nutrient concentration variation was mostly explained by differences between IB and SW, followed by differences between species and, in the case of phosphorus, soil nutrient availability. IB nutrient concentrations were four times those of SW, with root tissues having slightly higher concentrations than stem tissues. Scaling between IB and SW, and between stems and roots, was generally isometric. In cross‐sections, IB contributed half of total nutrients in roots and a third in stems. Our results highlight the important role of IB and SW for nutrient storage, the coordination in nutrient allocation across tissues and organs, and the need to differentiate between IB and SW to understand plant nutrient allocation.

Artificial Floating Islands for the Removal of Nutrients and Improvement of the Quality of Urban Wastewater

“…To determine the concentration of NO 3 -N and PO 4 3 -P in roots and leaves, each plant was cut and divided into roots, stems, and leaves; subsequently, these were dried in an oven at 100 ± 5 • C for 4 h. Once the vegetative parts were dry, each part was ground in a mortar and then passed through a 40-mesh mesh [37,38]. The powder obtained was stored in polyethylene bags for the determination of nitrate and phosphate concentrations.…”

Woody debris removal modifies carbon stocks and soil properties in a fragmented tropical rainforest

“…Previous research has shown that reducing leaf litter inputs can increase soil bulk density with possible detrimental consequences for soil fertility (Sayer, 2006), suggesting that the impacts of CWD removal on soil bulk density and fertility are worth examining. Recent studies also offer evidence that the wood of tropical trees constitutes a significant reservoir of rock-derived (i.e., originally mobilized by rock weathering) nutrients such as phosphorus (P), potassium (K), magnesium (Mg), and calcium (Ca), in addition to nitrogen (Bauters et al, 2022;Heineman et al, 2016;Inagawa et al, 2023;Rosell et al, 2023). This suggests that CWD removal could also affect soil fertility in tropical forests by curtailing the recycling of key nutrients from vegetation to soil.…”