Holocene Dynamics of Temperate Rainforests in West-Central Patagonia
Analyses of long-term ecosystem dynamics offer insights into the conditions that have led to stability vs. rapid change in the past and the importance of disturbance in regulating community composition. In this study, we (1) used lithology, pollen, and charcoal data from Mallín Casanova (47°S) to re...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Frontiers Media S.A.
2018-01-01
|
Series: | Frontiers in Ecology and Evolution |
Subjects: | |
Online Access: | http://journal.frontiersin.org/article/10.3389/fevo.2017.00177/full |
id |
doaj-5338da69ad84443992d7f139556521dc |
---|---|
record_format |
Article |
spelling |
doaj-5338da69ad84443992d7f139556521dc2020-11-25T00:28:42ZengFrontiers Media S.A.Frontiers in Ecology and Evolution2296-701X2018-01-01510.3389/fevo.2017.00177323398Holocene Dynamics of Temperate Rainforests in West-Central PatagoniaVirginia Iglesias0Simon G. Haberle1Andrés Holz2Cathy Whitlock3Cathy Whitlock4Montana Institute on Ecosystems, Montana State University, Bozeman, MT, United StatesSchool of Culture, History and Language, Australian National University, Canberra, ACT, AustraliaDepartment of Geography, Portland State University, Portland, OR, United StatesMontana Institute on Ecosystems, Montana State University, Bozeman, MT, United StatesDepartment of Earth Sciences, Montana State University, Bozeman, MT, United StatesAnalyses of long-term ecosystem dynamics offer insights into the conditions that have led to stability vs. rapid change in the past and the importance of disturbance in regulating community composition. In this study, we (1) used lithology, pollen, and charcoal data from Mallín Casanova (47°S) to reconstruct the wetland, vegetation, and fire history of west-central Patagonia; and (2) compared the records with independent paleoenvironmental and archeological information to assess the effects of past climate and human activity on ecosystem dynamics. Pollen data indicate that Nothofagus-Pilgerodendron forests were established by 9,000 cal yr BP. Although the biodiversity of the understory increased between 8,480 and 5,630 cal yr BP, forests remained relatively unchanged from 9,000 to 2,000 cal yr BP. The charcoal record registers high fire-episode frequency in the early Holocene followed by low biomass burning between 6,500 and 2,000 cal yr BP. Covarying trends in charcoal, bog development, and Neoglacial advances suggest that climate was the primary driver of these changes. After 2,000 cal yr BP, the proxy data indicate (a) increased fire-episode frequency; (b) centennial-scale shifts in bog and forest composition; (c) the emergence of vegetation-fire linkages not recorded in previous times; and (d) paludification in the last 500 years possibly associated with forest loss. Our results therefore suggest that Nothofagus-Pilgerodendron dominance was maintained through much of the Holocene despite long-term changes in climate and fire. Unparalleled fluctuations in local ecosystems during the last two millennia were governed by disturbance-vegetation-hydrology feedbacks likely triggered by greater climate variability and deforestation.http://journal.frontiersin.org/article/10.3389/fevo.2017.00177/fullanthropogenic impactcharcoalclimatepollenstabilityvegetation |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Virginia Iglesias Simon G. Haberle Andrés Holz Cathy Whitlock Cathy Whitlock |
spellingShingle |
Virginia Iglesias Simon G. Haberle Andrés Holz Cathy Whitlock Cathy Whitlock Holocene Dynamics of Temperate Rainforests in West-Central Patagonia Frontiers in Ecology and Evolution anthropogenic impact charcoal climate pollen stability vegetation |
author_facet |
Virginia Iglesias Simon G. Haberle Andrés Holz Cathy Whitlock Cathy Whitlock |
author_sort |
Virginia Iglesias |
title |
Holocene Dynamics of Temperate Rainforests in West-Central Patagonia |
title_short |
Holocene Dynamics of Temperate Rainforests in West-Central Patagonia |
title_full |
Holocene Dynamics of Temperate Rainforests in West-Central Patagonia |
title_fullStr |
Holocene Dynamics of Temperate Rainforests in West-Central Patagonia |
title_full_unstemmed |
Holocene Dynamics of Temperate Rainforests in West-Central Patagonia |
title_sort |
holocene dynamics of temperate rainforests in west-central patagonia |
publisher |
Frontiers Media S.A. |
series |
Frontiers in Ecology and Evolution |
issn |
2296-701X |
publishDate |
2018-01-01 |
description |
Analyses of long-term ecosystem dynamics offer insights into the conditions that have led to stability vs. rapid change in the past and the importance of disturbance in regulating community composition. In this study, we (1) used lithology, pollen, and charcoal data from Mallín Casanova (47°S) to reconstruct the wetland, vegetation, and fire history of west-central Patagonia; and (2) compared the records with independent paleoenvironmental and archeological information to assess the effects of past climate and human activity on ecosystem dynamics. Pollen data indicate that Nothofagus-Pilgerodendron forests were established by 9,000 cal yr BP. Although the biodiversity of the understory increased between 8,480 and 5,630 cal yr BP, forests remained relatively unchanged from 9,000 to 2,000 cal yr BP. The charcoal record registers high fire-episode frequency in the early Holocene followed by low biomass burning between 6,500 and 2,000 cal yr BP. Covarying trends in charcoal, bog development, and Neoglacial advances suggest that climate was the primary driver of these changes. After 2,000 cal yr BP, the proxy data indicate (a) increased fire-episode frequency; (b) centennial-scale shifts in bog and forest composition; (c) the emergence of vegetation-fire linkages not recorded in previous times; and (d) paludification in the last 500 years possibly associated with forest loss. Our results therefore suggest that Nothofagus-Pilgerodendron dominance was maintained through much of the Holocene despite long-term changes in climate and fire. Unparalleled fluctuations in local ecosystems during the last two millennia were governed by disturbance-vegetation-hydrology feedbacks likely triggered by greater climate variability and deforestation. |
topic |
anthropogenic impact charcoal climate pollen stability vegetation |
url |
http://journal.frontiersin.org/article/10.3389/fevo.2017.00177/full |
work_keys_str_mv |
AT virginiaiglesias holocenedynamicsoftemperaterainforestsinwestcentralpatagonia AT simonghaberle holocenedynamicsoftemperaterainforestsinwestcentralpatagonia AT andresholz holocenedynamicsoftemperaterainforestsinwestcentralpatagonia AT cathywhitlock holocenedynamicsoftemperaterainforestsinwestcentralpatagonia AT cathywhitlock holocenedynamicsoftemperaterainforestsinwestcentralpatagonia |
_version_ |
1725334744935170048 |