Open AccessChanges in soil bacterial community triggered by drought‐induced gap succession preceded changes in soil C stocks and quality
Author(s) -
Yuste Jorge Curiel,
Barba Josep,
FernandezGonzalez Antonio José,
FernandezLopez Manuel,
Mattana Stefania,
MartinezVilalta Jordi,
Nolis Pau,
Lloret Francisco
Publication year - 2012
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.409
Subject(s) - ecological succession , soil water , population , biology , ecology , soil quality , actinobacteria , environmental science , botany , bacteria , genetics , demography , 16s ribosomal rna , sociology
The aim of this study was to understand how drought‐induced tree mortality and subsequent secondary succession would affect soil bacterial taxonomic composition as well as soil organic matter ( SOM ) quantity and quality in a mixed Mediterranean forest where the S cots pine ( P inus sylvestris ) population, affected by climatic drought‐induced die‐off, is being replaced by H olm‐oaks ( HO ; Q uercus ilex ). We apply a high throughput DNA pyrosequencing technique and 13 C solid‐state Nuclear Magnetic Resonance ( CP ‐ MAS 13 C NMR ) to soils within areas of influence (defined as an surface with 2‐m radius around the trunk) of different trees: healthy and affected (defoliated) pines, pines that died a decade ago and healthy HO s. Soil respiration was also measured in the same spots during a spring campaign using a static close‐chamber method (soda lime). A decade after death, and before aerial colonization by the more competitive HO s have even taken place, we could not find changes in soil C pools (quantity and/or quality) associated with tree mortality and secondary succession. Unlike C pools, bacterial diversity and community structure were strongly determined by tree mortality. Convergence between the most abundant taxa of soil bacterial communities under dead pines and colonizer trees ( HO s) further suggests that physical gap colonization was occurring below‐ground before above‐ground colonization was taken place. Significantly higher soil respiration rates under dead trees, together with higher bacterial diversity and anomalously high representation of bacteria commonly associated with copiotrophic environments (r‐strategic bacteria) further gives indications of how drought‐induced tree mortality and secondary succession were influencing the structure of microbial communities and the metabolic activity of soils.