Van Langenhove, L., I. A. Janssens, Verryckt, Lore L. Brechet, I. P. Hartley, C. Stahl, E. Courtois, I. Urbina, O. Grau, J. Sardans, G. Peguero, A. Gargallo-Garriga, J. Peñuelas, and S. Vicca. 2020.
Tree growth on weathered soils in lowland tropical forests is limited by low phosphorous (P) availability. However, nutrient manupulation experiments do not always increase the P content in these trees, which raises the question whether trees are taking up added P. In French Guianese lowland rainforest, we measured changes in nitrogen (N) and P availability before and up to two months after N and P fertilizer addition, in soils with intact root systems and in soils where roots and mycorrhizal fungi were excluded by root exclusion cylinders. When the root system was excluded, P addition increased P availability to a much greater extent and for a longer time than in soils with an intact root system. Soil N dynamics were unaffected by root presence/absence. These results indicate rapid P uptake, but not N uptake, by tree roots, suggesting a very effective P acquisition process in these lowland rainforests.
Tropical forest Phosphorus Nitrogen Fertilization Root system Plant root simulator probes
