Modelling the critical transition from Chilean evergreen forest to savanna: Early warning signals and livestock management

Research output: Contribution to journalArticle

Abstract

Semi-desert areas are sensitive to changes in rainfall and agricultural pressure, prone to abrupt changes and to the collapse of ecological functions. The sclerophyllous evergreen forest of central Chile, known as matorral, has been extensively overgrazed by domestic livestock. As a consequence, the native and endemic species of this forest community have been replaced by a savanna-type environment dominated by the species Acacia caven, known as espinales. It has been hypothesized that the collapse of matorral forest can be abrupt, and the two ecosystems represent two alternative stable states. To understand the ecological dynamics that occur during this transition, their signature in space, and the consequences of livestock management, a cellular automata model that considers the local interaction among forest vegetation, Acacia, and livestock management was developed. By simulating and analyzing the process of fragmentation in space and time, in a gradient of livestock pressure and aridity, the results show that the system exhibits properties of “robust criticality” with a shift of patch-size distributions from models matching power-laws to models matching truncated power-laws as livestock pressure increases nearby the point of collapse. Simulation results in scenarios with rotation of livestock at the tipping point reveal the interaction between resting frequency and forest conservation. These results provide information to design better management strategies in human-modified landscapes in the remaining Chilean matorral.

Original languageEnglish (US)
Pages (from-to)115-123
Number of pages9
JournalEcological Modelling
Volume388
DOIs
StatePublished - Nov 24 2018

Fingerprint

livestock farming
evergreen forest
savanna
livestock
modeling
power law
cellular automaton
patch size
aridity
endemic species
native species
fragmentation
desert
rainfall
ecosystem
vegetation
simulation

Keywords

  • Acacia caven
  • Alternative ecosystem states
  • Ecosystem shift
  • Matorral
  • Robust criticality

ASJC Scopus subject areas

  • Ecological Modeling

Cite this

@article{4a098461604f49dba762c529b3ea2b7b,
title = "Modelling the critical transition from Chilean evergreen forest to savanna: Early warning signals and livestock management",
abstract = "Semi-desert areas are sensitive to changes in rainfall and agricultural pressure, prone to abrupt changes and to the collapse of ecological functions. The sclerophyllous evergreen forest of central Chile, known as matorral, has been extensively overgrazed by domestic livestock. As a consequence, the native and endemic species of this forest community have been replaced by a savanna-type environment dominated by the species Acacia caven, known as espinales. It has been hypothesized that the collapse of matorral forest can be abrupt, and the two ecosystems represent two alternative stable states. To understand the ecological dynamics that occur during this transition, their signature in space, and the consequences of livestock management, a cellular automata model that considers the local interaction among forest vegetation, Acacia, and livestock management was developed. By simulating and analyzing the process of fragmentation in space and time, in a gradient of livestock pressure and aridity, the results show that the system exhibits properties of “robust criticality” with a shift of patch-size distributions from models matching power-laws to models matching truncated power-laws as livestock pressure increases nearby the point of collapse. Simulation results in scenarios with rotation of livestock at the tipping point reveal the interaction between resting frequency and forest conservation. These results provide information to design better management strategies in human-modified landscapes in the remaining Chilean matorral.",
keywords = "Acacia caven, Alternative ecosystem states, Ecosystem shift, Matorral, Robust criticality",
author = "Andres Baeza-Castro",
year = "2018",
month = "11",
day = "24",
doi = "10.1016/j.ecolmodel.2018.09.022",
language = "English (US)",
volume = "388",
pages = "115--123",
journal = "Ecological Modelling",
issn = "0304-3800",
publisher = "Elsevier",

}

TY - JOUR

T1 - Modelling the critical transition from Chilean evergreen forest to savanna

T2 - Early warning signals and livestock management

AU - Baeza-Castro, Andres

PY - 2018/11/24

Y1 - 2018/11/24

N2 - Semi-desert areas are sensitive to changes in rainfall and agricultural pressure, prone to abrupt changes and to the collapse of ecological functions. The sclerophyllous evergreen forest of central Chile, known as matorral, has been extensively overgrazed by domestic livestock. As a consequence, the native and endemic species of this forest community have been replaced by a savanna-type environment dominated by the species Acacia caven, known as espinales. It has been hypothesized that the collapse of matorral forest can be abrupt, and the two ecosystems represent two alternative stable states. To understand the ecological dynamics that occur during this transition, their signature in space, and the consequences of livestock management, a cellular automata model that considers the local interaction among forest vegetation, Acacia, and livestock management was developed. By simulating and analyzing the process of fragmentation in space and time, in a gradient of livestock pressure and aridity, the results show that the system exhibits properties of “robust criticality” with a shift of patch-size distributions from models matching power-laws to models matching truncated power-laws as livestock pressure increases nearby the point of collapse. Simulation results in scenarios with rotation of livestock at the tipping point reveal the interaction between resting frequency and forest conservation. These results provide information to design better management strategies in human-modified landscapes in the remaining Chilean matorral.

AB - Semi-desert areas are sensitive to changes in rainfall and agricultural pressure, prone to abrupt changes and to the collapse of ecological functions. The sclerophyllous evergreen forest of central Chile, known as matorral, has been extensively overgrazed by domestic livestock. As a consequence, the native and endemic species of this forest community have been replaced by a savanna-type environment dominated by the species Acacia caven, known as espinales. It has been hypothesized that the collapse of matorral forest can be abrupt, and the two ecosystems represent two alternative stable states. To understand the ecological dynamics that occur during this transition, their signature in space, and the consequences of livestock management, a cellular automata model that considers the local interaction among forest vegetation, Acacia, and livestock management was developed. By simulating and analyzing the process of fragmentation in space and time, in a gradient of livestock pressure and aridity, the results show that the system exhibits properties of “robust criticality” with a shift of patch-size distributions from models matching power-laws to models matching truncated power-laws as livestock pressure increases nearby the point of collapse. Simulation results in scenarios with rotation of livestock at the tipping point reveal the interaction between resting frequency and forest conservation. These results provide information to design better management strategies in human-modified landscapes in the remaining Chilean matorral.

KW - Acacia caven

KW - Alternative ecosystem states

KW - Ecosystem shift

KW - Matorral

KW - Robust criticality

UR - http://www.scopus.com/inward/record.url?scp=85054620175&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85054620175&partnerID=8YFLogxK

U2 - 10.1016/j.ecolmodel.2018.09.022

DO - 10.1016/j.ecolmodel.2018.09.022

M3 - Article

VL - 388

SP - 115

EP - 123

JO - Ecological Modelling

JF - Ecological Modelling

SN - 0304-3800

ER -