DOI: 10.5061/dryad.905qfttm3
title: Interspecific differences in the responses of root phosphatase activities and morphology to nitrogen and phosphorus fertilization in Bornean tropical rain forests

description: Soil organic phosphorus (P) compounds can be the main P source for plants
 in P‐limited tropical rainforests. Phosphorus occurs in diverse chemical
 forms, including monoester P, diester P, and phytate, which require
 enzymatic hydrolysis by phosphatase into inorganic P before assimilation
 by plants. The interactions between plant interspecific differences in
 organic P acquisition strategies via phosphatase activities with root
 morphological traits would lead to P resource partitioning, but they have
 not been rigorously evaluated. We measured the activities of three classes
 of phosphatases (phosphomonoesterase, PME; phosphodiesterase, PDE; and
 phytase, PhT), specific root length (SRL), root diameter, and root tissue
 density in mature tree species with different mycorrhizal associations
 (ectomycorrhizal [ECM] or arbuscular mycorrhizal [AM]) and different
 successional status (climax or pioneer species) in Sabah, Malaysia. We
 studied nitrogen (N)‐ and P‐fertilized plots to evaluate the acquisition
 strategies for organic P under P‐limited conditions 7 years after
 fertilization was initiated. P fertilization reduced the PME activity in
 all studied species and reduced PhT and PDE activities more in climax
 species than in the two pioneer species, irrespective of the mycorrhizal
 type. PDE activity increased in some climax species after N fertilization,
 suggesting that these species allocate excess N to the synthesis of PDE.
 Moreover, PME and PhT activities, but not PDE activity, correlated
 positively with SRL. We suggest that climax species tend to be more
 strongly dependent on recalcitrant organic P (i.e., phytate and/or diester
 P) than pioneer species, regardless of the mycorrhizal type. We also
 suggest that trees in which root PME or PhT activity is enhanced can
 increase their SRL to acquire P efficiently. Resource partitioning of soil
 organic P would occur among species through differences in their
 phosphatase activities, which plays potentially ecologically important
 role in reducing the competition among coexisting tree species in lowland
 tropical rainforests.
description: # Interspecific differences in the responses of root phosphatase
 activities and morphology to nitrogen and phosphorus fertilization in
 Bornean tropical rain forests Dataset DOI:
 [https://doi.org/10.5061/dryad.905qfttm3](https://doi.org/10.5061/dryad.905qfttm3) ## Description of the data and file structure This is supplementary data used for analysis in the paper entitled “Interspecific differences in the responses of root phosphatase activities and morphology to nitrogen and phosphorus fertilization in Bornean tropical rain forests”. The csv files include the information on species name and values of root phosphatases and morphology. There are some missing data because of limited sample availability, which are indicated as NA. ### Files and variables #### File: Apase.csv and Morphology.csv ##### Variables Common variable names: * species: Species name of the sampled individual. * treatment: fertilization treatment. C: control, N: N fertilization, P: P fertilization, NP: N and P fertilization together * Plant_ID: tree tag number of the sampled individual. * root_replication: Replicate number for an individual. Variable names in Apase.csv * PME: Fine-root phosphomonoesterase activity (µmol *p*NP g–1 hr-1) * PDE: Fine-root phosphodiesterase activity (µmol *p*NP g–1 hr-1) * PhT: Fine-root phytase activity (µmol PO4* *g–1 hr-1) Variable names in Morphology.csv * dia: root diamter (mm) * RTD: root tissue density (g cm–3) * SRL: specific root length (m g–1)