A postglacial palaeoecological record from the San Juan Mountains of Colorado USA: Fire, climate and vegetation history

Jaime L. Toney, Scott R Anderson

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

Continuous sediment, charcoal and pollen records were developed from a ∼4.5 m sediment core from Little Molas Lake (LML), 3370 m elevation, San Juan County, CO. LML formed by 11 200 cal. BP subsequent to glacial retreat. Turbated clay and gyttja was derived from in-lake productivity and outwash sediments from the drainage basin from ∼11 200 cal. BP until ∼10 200 cal. BP. Cessation of glacial input and replacement of tundra with Picea forest correlates with the termination of the Younger Dryas and indicates warming. An increase in diploxylon pollen (cf. P. ponderosa), probably from lower elevations, reflects the influence of the southwestern monsoon c. 10 160 cal. BP. Pollen ratios indicate that Picea and other conifers persisted near the lake for the remainer of the Holocene. The driest Holocene period occurs c. 6200 to 5900 cal. BP, when lake levels were the lowest as indicated by all the proxy records. Wetter conditions during the last c. 2600 cal. BP favoured the expansion of P. edulis and P. ponderosa. Lateglacial fire events occurred on average every 65 years with a doubling of the fire return interval in the early Holocene. The former may reflect an increase in biomass for burning during a period of rapid vegetation turnover. The lowest fire event frequency occurs during the Neoglacial (after c. 4100), during a period of moister and cooler climate. The most recent pronounced peak in charcoal coincides with the historically documented AD 1879 Lime Creek Burn.

Original languageEnglish (US)
Pages (from-to)505-517
Number of pages13
JournalHolocene
Volume16
Issue number4
DOIs
StatePublished - Jun 2006

Fingerprint

vegetation history
Postglacial
mountain
pollen
lake
Holocene
climate
charcoal
gyttja
Neoglacial
outwash
Younger Dryas
lake level
tundra
drainage basin
sediment
lime
coniferous tree
sediment core
turnover

Keywords

  • Charcoal analysis
  • Fire history
  • Holocene
  • Palaeoecology
  • Pollen analysis
  • Southern Rocky Mountains
  • Vegetation history

ASJC Scopus subject areas

  • Earth and Planetary Sciences (miscellaneous)

Cite this

A postglacial palaeoecological record from the San Juan Mountains of Colorado USA : Fire, climate and vegetation history. / Toney, Jaime L.; Anderson, Scott R.

In: Holocene, Vol. 16, No. 4, 06.2006, p. 505-517.

Research output: Contribution to journalArticle

@article{bf60a5cd80b64fcc9cb6a6436a366c08,
title = "A postglacial palaeoecological record from the San Juan Mountains of Colorado USA: Fire, climate and vegetation history",
abstract = "Continuous sediment, charcoal and pollen records were developed from a ∼4.5 m sediment core from Little Molas Lake (LML), 3370 m elevation, San Juan County, CO. LML formed by 11 200 cal. BP subsequent to glacial retreat. Turbated clay and gyttja was derived from in-lake productivity and outwash sediments from the drainage basin from ∼11 200 cal. BP until ∼10 200 cal. BP. Cessation of glacial input and replacement of tundra with Picea forest correlates with the termination of the Younger Dryas and indicates warming. An increase in diploxylon pollen (cf. P. ponderosa), probably from lower elevations, reflects the influence of the southwestern monsoon c. 10 160 cal. BP. Pollen ratios indicate that Picea and other conifers persisted near the lake for the remainer of the Holocene. The driest Holocene period occurs c. 6200 to 5900 cal. BP, when lake levels were the lowest as indicated by all the proxy records. Wetter conditions during the last c. 2600 cal. BP favoured the expansion of P. edulis and P. ponderosa. Lateglacial fire events occurred on average every 65 years with a doubling of the fire return interval in the early Holocene. The former may reflect an increase in biomass for burning during a period of rapid vegetation turnover. The lowest fire event frequency occurs during the Neoglacial (after c. 4100), during a period of moister and cooler climate. The most recent pronounced peak in charcoal coincides with the historically documented AD 1879 Lime Creek Burn.",
keywords = "Charcoal analysis, Fire history, Holocene, Palaeoecology, Pollen analysis, Southern Rocky Mountains, Vegetation history",
author = "Toney, {Jaime L.} and Anderson, {Scott R}",
year = "2006",
month = "6",
doi = "10.1191/0959683606hl946rp",
language = "English (US)",
volume = "16",
pages = "505--517",
journal = "Holocene",
issn = "0959-6836",
publisher = "SAGE Publications Ltd",
number = "4",

}

TY - JOUR

T1 - A postglacial palaeoecological record from the San Juan Mountains of Colorado USA

T2 - Fire, climate and vegetation history

AU - Toney, Jaime L.

AU - Anderson, Scott R

PY - 2006/6

Y1 - 2006/6

N2 - Continuous sediment, charcoal and pollen records were developed from a ∼4.5 m sediment core from Little Molas Lake (LML), 3370 m elevation, San Juan County, CO. LML formed by 11 200 cal. BP subsequent to glacial retreat. Turbated clay and gyttja was derived from in-lake productivity and outwash sediments from the drainage basin from ∼11 200 cal. BP until ∼10 200 cal. BP. Cessation of glacial input and replacement of tundra with Picea forest correlates with the termination of the Younger Dryas and indicates warming. An increase in diploxylon pollen (cf. P. ponderosa), probably from lower elevations, reflects the influence of the southwestern monsoon c. 10 160 cal. BP. Pollen ratios indicate that Picea and other conifers persisted near the lake for the remainer of the Holocene. The driest Holocene period occurs c. 6200 to 5900 cal. BP, when lake levels were the lowest as indicated by all the proxy records. Wetter conditions during the last c. 2600 cal. BP favoured the expansion of P. edulis and P. ponderosa. Lateglacial fire events occurred on average every 65 years with a doubling of the fire return interval in the early Holocene. The former may reflect an increase in biomass for burning during a period of rapid vegetation turnover. The lowest fire event frequency occurs during the Neoglacial (after c. 4100), during a period of moister and cooler climate. The most recent pronounced peak in charcoal coincides with the historically documented AD 1879 Lime Creek Burn.

AB - Continuous sediment, charcoal and pollen records were developed from a ∼4.5 m sediment core from Little Molas Lake (LML), 3370 m elevation, San Juan County, CO. LML formed by 11 200 cal. BP subsequent to glacial retreat. Turbated clay and gyttja was derived from in-lake productivity and outwash sediments from the drainage basin from ∼11 200 cal. BP until ∼10 200 cal. BP. Cessation of glacial input and replacement of tundra with Picea forest correlates with the termination of the Younger Dryas and indicates warming. An increase in diploxylon pollen (cf. P. ponderosa), probably from lower elevations, reflects the influence of the southwestern monsoon c. 10 160 cal. BP. Pollen ratios indicate that Picea and other conifers persisted near the lake for the remainer of the Holocene. The driest Holocene period occurs c. 6200 to 5900 cal. BP, when lake levels were the lowest as indicated by all the proxy records. Wetter conditions during the last c. 2600 cal. BP favoured the expansion of P. edulis and P. ponderosa. Lateglacial fire events occurred on average every 65 years with a doubling of the fire return interval in the early Holocene. The former may reflect an increase in biomass for burning during a period of rapid vegetation turnover. The lowest fire event frequency occurs during the Neoglacial (after c. 4100), during a period of moister and cooler climate. The most recent pronounced peak in charcoal coincides with the historically documented AD 1879 Lime Creek Burn.

KW - Charcoal analysis

KW - Fire history

KW - Holocene

KW - Palaeoecology

KW - Pollen analysis

KW - Southern Rocky Mountains

KW - Vegetation history

UR - http://www.scopus.com/inward/record.url?scp=33745974499&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33745974499&partnerID=8YFLogxK

U2 - 10.1191/0959683606hl946rp

DO - 10.1191/0959683606hl946rp

M3 - Article

AN - SCOPUS:33745974499

VL - 16

SP - 505

EP - 517

JO - Holocene

JF - Holocene

SN - 0959-6836

IS - 4

ER -