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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Disentangling the roles of resource availability and disturbance in fine and coarse root biomass in savanna

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Loiola, Priscilla P. [1] ; Carvalho, Gustavo H. [2] ; Batalha, Marco A. [1]
Total Authors: 3
[1] Univ Fed Sao Carlos, Dept Bot, Rod Washington Luis Km 235, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Estadual Santa Cruz, Dept Biol Sci, Santa Cruz - Brazil
Total Affiliations: 2
Document type: Journal article
Source: AUSTRAL ECOLOGY; v. 41, n. 3, p. 255-262, MAY 2016.
Web of Science Citations: 3

Savannas are among the most unknown biomes concerning the plant below-ground system. Root biomass might be influenced by the availability of limiting resources and by the type and intensity of disturbances, mediated by the plant functional attributes related to environmental conditions. Fine and coarse roots should be affected differently: the former should be more responsive to resource supplies, whilst the latter should be related to changes in disturbance frequency. We studied the roles of soil fertility, topography of the plots indicating water availability, fire frequency and plant resistance to fire in affecting fine and coarse root biomass. We sampled the root biomass, environmental variables and functional attributes of all individuals present in 100 plots in savanna physiognomies of cerrado, in central Brazil. We used structural equation modelling to test our hypothesis and found that shallow root biomass, from 0 to 20cm deep, was not caused by resource availability, by disturbances, as fire or drought, or by functional attributes. Biotic interactions were not considered in our study, but they may have a central role in affecting the shallow root biomass. In the deep layer, from 20 to 100cm deep, we identified soil fertility and recent fires as the main factors causing changes in fine and coarse root biomass in the cerrado, respectively. Low nutrient availability in the soil caused higher fine root biomass, increasing the uptake of resources, whereas recent fires led to less coarse root biomass below 20cm deep, probably due to the higher dominance of the herbaceous layer in the plots, with less coarse root biomass. According to our expectation, fine roots were mostly affected by nutrient availability in the soil, whereas coarse roots were more related to disturbance, in our case, recent fires. (AU)

FAPESP's process: 10/00982-0 - Belowground biomass production in a Brazilian Savanna: relationships with fire, soil, and topographic features
Grantee:Priscilla de Paula Loiola
Support type: Scholarships in Brazil - Doctorate