Linking tree rings, summer aridity, and regional fire data: an example from the boreal forests of the Komi Republic, East European Russia

2004 ◽  
Vol 34 (11) ◽  
pp. 2327-2339 ◽  
Author(s):  
Igor Drobyshev ◽  
Mats Niklasson
Keyword(s):  
Tree Ring ◽  
Boreal Forests ◽  
Fire Suppression ◽  
Siberian Larch ◽  
Komi Republic ◽  
Burned Area ◽  
Annual Number ◽  
Climate Data ◽  
Tree Ring Data ◽  
Fire Activity

To evaluate the potential use of tree-ring data as a proxy for fire activity at the scale of a large boreal region, we analyzed a set of regional tree-ring chronologies of Siberian larch (Larix sibirica L.), a spatially implicit annual fire record, and monthly climate data for the Komi Republic for the period 1950–1990. In most years, annually burned area was below 0.001% of the republic's forested area and reached up to 0.7% during fire-prone years. Principal components (PC) of summer aridity resolved 64.2% of the annual variation in the number of fires, 12.2% in the average fire size, and 59.2% in the annually burned area. In turn, tree-ring PCs explained 65.2% of variation in fire-related weather PCs. Dendrochronological reconstruction of the annual number of fires and of the log-transformed annually burned area predicted 27.0% and 40.1% of the high-frequency variance of these variables, respectively. Coefficient of efficiency, a measure of reconstruction usefulness, reached 0.081 (number of fires) and 0.315 (annual area burned), supporting the obtained index as a realistic proxy for regional fire activity. Decadal variation in coefficient of efficiency values suggested improved monitoring accuracy since 1960 and more effective fire suppression during the last studied decade (1980–1990).

Determinants of fire activity during the last 3500 yr at a wildland—urban interface, Alberta, Canada

2016 ◽  
Vol 86 (3) ◽  
pp. 247-259 ◽  
Author(s):  
Emma L. Davis ◽  
Colin J. Courtney Mustaphi ◽  
Amber Gall ◽  
Michael F.J. Pisaric ◽  
Jesse C. Vermaire ◽  
...  
Keyword(s):  
Tree Ring ◽  
Management Practices ◽  
Vegetation History ◽  
Fire Regime ◽  
Fire Suppression ◽  
Fire Frequency ◽  
Sources Of Information ◽  
Fire Activity ◽  
Historical Range

AbstractLong-term records of wildfires and their controlling factors are important sources of information for informing land management practices. Here, dendrochronology and lake sediment analyses are used to develop a 3500-yr fire and vegetation history for a montane forest in Jasper National Park, Alberta, Canada. The tree-ring record (AD 1771-2012) indicates that this region historically experienced a mixed-severity fire regime, and that effective fire suppression excluded widespread fire events from the study area during the 20th century. A sediment core collected from Little Trefoil Lake, located near the Jasper townsite, is analyzed for subfossil pollen and macroscopic charcoal (>150 μm). When comparing the tree-ring record to the 3500-yr record of sediment-derived fire events, only high-severity fires are represented in the charcoal record. Comparisons between the charcoal record and historical climate and pollen data indicate that climate and vegetation composition have been important controls on the fire regime for most of the last 3500 yr. Although fire frequency is presently within the historical range of variability, the fire return interval of the last 150 yr is longer than expected given modern climate and vegetation conditions, indicating that humans have become the main control on fire activity around Little Trefoil Lake.

Comparison between Blue Intensity (BI) and Maximum Latewood Density (MXD) tree-ring chronologies from the North American Boreal forests

2020 ◽  
Author(s):  
Laia Andreu-Hayles ◽  
Rosanne D'Arrigo ◽  
Rose Oelkers ◽  
Kevin Anchukaitis ◽  
Greg Wiles ◽  
...  
Keyword(s):  
High Resolution ◽  
North America ◽  
Tree Ring ◽  
Boreal Forests ◽  
Ring Width ◽  
Maximum Latewood Density ◽  
Latewood Density ◽  
Tree Ring Data ◽  
Summer Temperatures ◽  
Blue Intensity

<p>Tree ring-width (TRW) and Maximum Latewood Density (MXD) series have been largely used to develop high-resolution temperature reconstructions for the Northern Hemisphere. The divergence phenomenon, a weakening of the positive relationship between TRW and summer temperatures, has been observed particularly in northwestern North America chronologies. In contrast, MXD datasets have shown a more stable relationship with summer temperatures, but it is costly and labor-intensive to produce. Recently, methodological advances in image analyses have led to development of a less expensive and labor-intensive MXD proxy known as Blue Intensity (BI). Here, we compare 6 newly developed BI tree-ring chronologies of white spruce (<em>Picea glauca</em> [Moench] Voss) from high-latitude boreal forests in North America (Alaska in USA; Yukon and the Northwestern Territory in Canada), with MXD chronologies developed at the same sites. We assessed the quality of BI in relation to MXD based on mean correlation between trees, chronology reliability based on the Expressed Population Signal (EPS), spectral properties, and the strength and spatial extent of the temperature signal. Individual BI chronologies established significant correlations with summer temperatures showing a similar strength and spatial cover than MXD chronologies. Overall, the BI tree-ring data is emerging as a valuable proxy for generating high-resolution temperature spatial reconstructions over northwestern America.</p>

scholarly journals A Comparative Analysis of Burned Area Datasets in Canadian Boreal Forest in 2000

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Laia Núñez-Casillas ◽  
José Rafael García Lázaro ◽  
José Andrés Moreno-Ruiz ◽  
Manuel Arbelo
Keyword(s):  
Comparative Analysis ◽  
Boreal Forest ◽  
Boreal Forests ◽  
Burned Area ◽  
Diverse Group ◽  
Spatial Accuracy ◽  
Noaa Avhrr ◽  
Fire Activity ◽  
Canadian Boreal Forest ◽  
Area Data

The turn of the new millennium was accompanied by a particularly diverse group of burned area datasets from different sensors in the Canadian boreal forests, brought together in a year of low global fire activity. This paper provides an assessment of spatial and temporal accuracy, by means of a fire-by-fire comparison of the following: two burned area datasets obtained from SPOT-VEGETATION (VGT) imagery, a MODIS Collection 5 burned area dataset, and three different datasets obtained from NOAA-AVHRR. Results showed that burned area data from MODIS provided accurate dates of burn but great omission error, partially caused by calibration problems. One of the VGT-derived datasets (L3JRC) represented the largest number of fire sites in spite of its great overall underestimation, whereas the GBA2000 dataset achieved the best burned area quantification, both showing delayed and very variable fire timing. Spatial accuracy was comparable between the 5 km and the 1 km AVHRR-derived datasets but was remarkably lower in the 8 km dataset leading, us to conclude that at higher spatial resolutions, temporal accuracy was lower. The probable methodological and contextual causes of these differences were analyzed in detail.

scholarly journals Satellite-based assessment of climate controls on US burned area

2012 ◽  
Vol 9 (6) ◽  
pp. 7853-7892 ◽  
Author(s):  
D. C. Morton ◽  
G. J. Collatz ◽  
D. Wang ◽  
J. T. Randerson ◽  
L. Giglio ◽  
...  
Keyword(s):  
Shortwave Radiation ◽  
Fire Season ◽  
Burned Area ◽  
Strongly Correlated ◽  
Climate Data ◽  
Spatial And Temporal Patterns ◽  
Fire Emissions ◽  
Mitigation And Adaptation ◽  
Fire Activity ◽  
Climate Controls

Abstract. Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate-fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burned area (BA), the Global Fire Emissions Database (GFED, 1997–2010) and Monitoring Trends in Burn Severity (MTBS, 1984–2009) BA products. For each US National Climate Assessment (NCA) region, we analyzed the relationships between monthly BA and potential evaporation (PE) derived from reanalysis climate data at 0.5° resolution. US fire activity increased over the past 25 yr, with statistically significant increases in MTBS BA for entire US and the Southeast and Southwest NCA regions. Monthly PE was strongly correlated with US fire activity, yet the climate driver of PE varied regionally. Fire season temperature and shortwave radiation were the primary controls on PE} and fire activity in the Alaska, while water deficit (precipitation – PE) was strongly correlated with fire activity in the Plains regions and Northwest US. BA and precipitation anomalies were negatively correlated in all regions, although fuel-limited ecosystems in the Southern Plains and Southwest exhibited positive correlations with longer lead times (6–12 months). Fire season PE increased from the 1980s–2000s, enhancing climate-driven fire risk in the southern and western US where PE-BA correlations were strongest. Spatial and temporal patterns of increasing fire season PE and BA during the 1990s–2000s highlight the potential sensitivity of US fire activity to climate change in coming decades. However, climate-fire relationships at the national scale are complex, based on the diversity of fire types, ecosystems, and ignition sources within each NCA region. Changes in the seasonality or magnitude of climate anomalies are therefore unlikely to result in uniform changes in US fire activity.

scholarly journals Testing for anthropogenic influence on fire regime for a 600-year period in the Jaksha area, Komi Republic, East European Russia

2004 ◽  
Vol 34 (10) ◽  
pp. 2027-2036 ◽  
Author(s):  
Igor Drobyshev ◽  
Mats Niklasson ◽  
Per Angelstam ◽  
Przemyslaw Majewski
Keyword(s):  
Human Impact ◽  
Tree Ring ◽  
Fire Regime ◽  
Ring Width ◽  
Komi Republic ◽  
European Russia ◽  
Statistical Relationship ◽  
East European ◽  
Tree Ring Data ◽  
A Site

In an attempt to quantitatively evaluate the natural versus anthropogenic signal in site fire histories, the statistical relationship between dendrochronologically dated fire events and tree-ring chronologies (deemed to be an independent proxy for climate variation) was analyzed for 14 sites in a 2600-km2 area of pine-dominated forests in the Komi Republic (East European Russia) over the period from 1424 to 1954. We developed a cumulative measure of statistical fit between two types of fire events (early- and late-season fires) and ring-width chronologies of Scots pine (Pinus sylvestris L.) (total ring- and latewood-width chronologies). For a given site, the statistical fit between fires and tree-ring data tended to decrease with an increasing proportion of unique fire years. Distance from a site to the nearest village (deemed to be a proxy of human impact) explained 50% of the variation in statistical fit between fires and tree-ring data. The fit decreased in the majority of the sites from the earlier (1424–1700) to the later (1700–1960) periods. We interpret this to be a result of increased human impact on the fire regime since 1700 due to intensified colonization of the area.

scholarly journals Oak decline in a southern Finnish forest as affected by a drought sequence

2014 ◽  
Vol 41 (1) ◽  
pp. 92-103 ◽  
Author(s):  
Kristina Sohar ◽  
Samuli Helama ◽  
Alar Läänelaid ◽  
Juha Raisio ◽  
Heikki Tuomenvirta
Keyword(s):  
Tree Ring ◽  
Time Lag ◽  
Ring Width ◽  
Summer Drought ◽  
Radial Increment ◽  
Pedunculate Oak ◽  
Climate Data ◽  
Tree Ring Data ◽  
The Dead ◽  
Old Trees

Abstract We investigated the decline of a pedunculate oak (Quercus robur L.) forest growing on shallow soil at the northern distributional limit of the species in southern Finland, using the dendroclimatic approach. About 200-year-old trees in three vigour classes — healthy, declining and dead — were sampled in 2008. Annual tree-ring, earlywood and latewood widths were measured and chronologies were established. The tree-ring data were correlated with monthly and seasonal climate data. Radial increment of oaks was positively related to the June and July precipitations. This was expressed especially in total ring width and latewood width, whereas the earlywood was more influenced by the warmer winter and spring. Furthermore, the correlation between the current year earlywood width and the preceding year latewood width was higher than between the earlywood and latewood of the same year. The analyses showed that the dead oaks and part of the declining oaks had ceased growing during 2005–2007 after a decadelong summer drought series. This indicates a time lag in the oak dieback. The radial growth of the declining and the dead oaks had dropped already since the 1990s, while the healthy oaks had better longterm growth and higher adaptive capacity to climate variation.

Early summer temperatures since 1670 A.D. for Central Kamchatka reconstructed based on a Siberian larch tree-ring width chronology

1996 ◽  
Vol 26 (11) ◽  
pp. 2048-2052 ◽  
Author(s):  
Moses Gostev ◽  
Gregory Wiles ◽  
Rosanne D'Arrigo ◽  
Gordon Jacoby ◽  
Peter Khomentovsky
Keyword(s):  
Tree Ring ◽  
Ring Width ◽  
Siberian Larch ◽  
Kamchatka Peninsula ◽  
Early Summer ◽  
Model Verification ◽  
Tree Ring Width ◽  
Tree Ring Data ◽  
Summer Temperatures ◽  
Larch Tree

A tree-ring width chronology of larch (Larixkurilensis Mayr) has been developed from along the Bystraya River near Esso in the interior valley of the Kamchatka Peninsula, Russia. The chronology, which covers from 1670 to 1992, explains 38% of the variance in May–June temperatures for the Esso meteorological station. This ring-width series is used to develop the first dendroclimatic reconstruction for Kamchatka. We caution that the Esso station record, the closest to the tree-ring site, is only 42 years in length, making model verification difficult. Periods of above-average temperatures are inferred for ca. 1750, 1800, and over the last few decades; colder than average conditions are inferred for 1710–1720, 1760–1770s, and 1860–1880s. The ring-width chronology cross-dates with other larch tree-ring data for Kamchatka and, during certain intervals, with a larch ring-width record from eastern Siberia. Comparison of the two records suggests that the insertion of a missing ring for the year 1816 in the eastern Siberian series is not justified. A birch (Betulaermanii Cham.) chronology from a coastal site near Petropavlovsk-Kamchatskiy correlates with July–August temperatures. Both the larch and more widespread birch species show promise for further dendroclimatic studies in Kamchatka.

A quantitative comparison of forest fires in central and northern California under early (1911–1924) and contemporary (2002–2015) fire suppression

2019 ◽  
Vol 28 (2) ◽  
pp. 138 ◽  
Author(s):  
Brandon M. Collins ◽  
Jay D. Miller ◽  
Eric E. Knapp ◽  
David B. Sapsis
Keyword(s):  
Forest Fires ◽  
Large Scale ◽  
Fire Regime ◽  
Fire Suppression ◽  
Major Change ◽  
Timber Harvesting ◽  
Burned Area ◽  
Annual Number ◽  
Regime Changes ◽  
Major Shift

Most studies of fire-regime changes in western North American forests rely on a reference period that pre-dates Euro-American settlement. Less is known about fire-regime changes relative to the early onset of major change agents, i.e. fire suppression and timber harvesting. We digitised ledgers that contained over 18000 individual fire records from 1911 through 1924 (early suppression period). We performed analyses comparing a subset of these fire records, largely in mixed-conifer forests, to similar records from 2002 through 2015 (contemporary period). Mapped ignition frequencies indicated similar geographic patterns for lightning-caused fires between periods, but notable shifts in certain areas for human-caused fires. There was no statistical difference in annual number of human-caused fires between the early suppression and contemporary time periods. However, there was a major shift in the distribution of burned area across fire size classes. Fires >12145ha accounted for 0–6% of total burned area in the early suppression period, and 53–73% in the contemporary period. Also, both the total number and percentage of fires >2024ha occurred significantly earlier in the year in the contemporary period. These shifts are likely driven by large-scale changes in fuel loads and continuity, and possibly exacerbated by climatic warming.

Climatic reconstruction from tree rings at Banff

1988 ◽  
Vol 18 (7) ◽  
pp. 888-900 ◽  
Author(s):  
E. O. Robertson ◽  
L. A. Jozsa
Keyword(s):  
Tree Ring ◽  
Transfer Functions ◽  
Principal Component ◽  
Regression Equations ◽  
Climate Variables ◽  
Climate Data ◽  
Data Set ◽  
Tree Ring Data ◽  
Variable Data ◽  
Component Scores

This study describes new techniques of tree-ring data preparation and data analysis for deriving proxy climate data from senescent Douglas-fir (Pseudotsugamenziesii var. glauca (Beissn.) Franco) trees from the Canadian Rockies, near Banff, Alberta. Fifteen annual tree-ring variables were measured by X-ray densitometry for 429 years (1550–1978) for 12 increment cores. Ring variable data were reduced to standard indexes using a 99-year normally weighted digital filter. Missing ring values were estimated using correlation with younger and more vigorous specimens, and each ring variable data set (12 cores × 429 years) was reduced to its first and second principal component score, to be used in the development of response and transfer functions. Factor analysis identified six subsets of ring variable principal component scores. The best multiple regression equations for transferring tree-ring variable principal components into reconstruction of climate were identified by screening all possible combinations of principal component scores between factor groups. Annual climate variables, such as total precipitation, did not transfer as successfully as did the shorter-term climate variables like June–July precipitation (R2 = 0.36 compared with 0.51). Verified transfer functions were developed for five climate variables which can now be reconstructed to 1550 a.d. (429 years).

Sign in / Sign up

Export Citation Format

Share Document