Journal Article

Soil-mediated filtering organizes tree assemblages in regenerating tropical forests

Pierce, Simon, Arroyo-Rodríguez, Víctor, Pinho, Bruno Ximenes, de Melo, Felipe Pimentel Lopes, Lohbeck, Madelon, Tabarelli, Marcelo

2018

Overview

1. Secondary forests are increasingly dominant in human-modified tropical landscapes, but the drivers of forest recovery remain poorly understood. Soil conditions influence plant community composition, and are expected to change over a gradient of succession. However, the role of soil conditions as an environmental filter driving community assembly during forest succession has rarely been explicitly assessed. 2. We evaluated the role of stand basal area and soil conditions on community assembly and its consequences for community functional properties along a chronosequence of Atlantic forest regeneration following sugar cane cultivation. Specifically, we tested whether community functional properties are related to stand basal area, soil fertility and soil moisture. Our expectations were that edaphic environmental filters play an increasingly important role along secondary succession by increasing functional trait convergence towards more conservative attributes. 3. We sampled soil and woody vegetation features across 15 second-growth (3-30 years) and 11 old-growth forest plots (300 m² each). We recorded tree functional traits related to resource-use strategies (specific leaf area, SLA; leaf dry matter content, LDMC; leaf area, LA; leaf thickness, LT; and leaf succulence, LS) and calculated community functional properties using the community-weighted mean (CWM) of each trait and the functional dispersion (FDis) of each trait separately and all traits together. 4. With exception of LA, all leaf traits were strongly associated with stand basal area; LDMC and SLA increased, while LT and LS decreased with forest development. Such changes in LDMC, LT and LS were also related to the decrease in soil nutrient availability and pH along succession, while soil moisture was weakly related to community functional properties. Considering all traits, as well as leaf thickness and succulence separately, FDis strongly decreased with increasing basal area and decreasing soil fertility along forest succession, presenting the lowest values in oldgrowth forests. 5. Synthesis. Our findings suggest that tropical forest regeneration may be a deterministic process shaped by soil conditions. Soil fertility operates as a key filter causing functional convergence towards more conservative resource-use strategies, such as leaves with higher leaf dry matter content.

• Publisher: John Wiley & Sons Ltd,Blackwell Publishing Ltd
• Subject: Area / Assembly / Atlantic forest / botanical composition / Brazil / chronosequences / Community assembly / Community composition / Convergence / Cultivation / Determinants of plant community diversity and structure / Dry matter / Dry matter content / Ecological succession / environmental factors / Environmental filtering / Fertility / Filtration / Forest regeneration / forest succession / forestry development / Forests / functional properties / Functional traits / Growth / Landscape / landscapes / Leaf area / Leaves / Mineral nutrients / Nutrient availability / old-growth forests / pH effects / Plant communities / Plant-soil (below-ground) interactions / Properties / Properties (attributes) / Regeneration / Regeneration (biological) / Saccharides / second growth / secondary forests / Secondary succession / Soil / Soil conditions / Soil conservation / Soil fertility / Soil moisture / Soil nutrients / soil quality / soil water / stand basal area / Sugar / Sugarcane / trees / Tropical climate / Tropical forests / Woody plants