Title: Multidecadal stability in tropical rain forest structure and dynamics across an old-growth landscape

Abstract

Have tropical rain forest landscapes changed directionally through recent decades? To answer this question requires tracking forest structure and dynamics through time and across within-forest environmental heterogeneity. While the impacts of major environmental gradients in soil nutrients, climate and topography on lowland tropical rain forest (TRF) structure and function have been extensively analyzed, the effects of the shorter environmental gradients typical of mesoscale TRF landscapes remain poorly understood. To evaluate multi-decadal performance of an old-growth TRF at the La Selva Biological Station, Costa Rica, we established 18 0.5-ha annually-censused forest inventory plots in a stratified-random design across major landscape edaphic gradients. Over the 17-year study period, there were moderate differences in stand dynamics and structure across these gradients but no detectable difference in woody productivity. We found large effects on forest structure and dynamics from the mega-Niño event at the outset of the study, with subdecadal recovery and subsequent stabilization. To extend the timeline to >40 years, we combined our findings with those from earlier studies at this site. While there were annual to multiannual variations in the structure and dynamics, particularly in relation to local disturbances and the mega-Niño event, at the longer temporal scale and broader spatial scalemore » this landscape was remarkably stable. This stability contrasts notably with a current hypothesis of increasing biomass and dynamics of TRF, which we term the Bigger and Faster Hypothesis (B&FH_o). We consider possible reasons for the contradiction and conclude that it is currently not possible to independently assess the vast majority of previously published B&FH_o evidence due to restricted data access.« less

Authors:

Clark, David B. ;

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Clark, Deborah A.; Oberbauer, Steven F.; Kellner, James R.; Zang, ed., RunGuo

Publication Date:

Thu Oct 05 00:00:00 EDT 2017

Research Org.:

Florida International Univ. (FIU), Miami, FL (United States)

Sponsoring Org.:

USDOE; National Science Foundation (NSF)

OSTI Identifier:

1398135

Alternate Identifier(s):

OSTI ID: 1499889

Grant/Contract Number:  

FG02-96ER62289

Resource Type:

Published Article

Journal Name:

PLoS ONE

Additional Journal Information:

Journal Name: PLoS ONE Journal Volume: 12 Journal Issue: 10; Journal ID: ISSN 1932-6203

Publisher:

Public Library of Science

Country of Publication:

United States

Language:

English

Subject:

54 ENVIRONMENTAL SCIENCES