Dynamics of an old-growth, fire-initiated, subalpine forest in southern interior British Columbia: tree-ring reconstruction of 2 year cycle spruce budworm outbreaks

2002 ◽  
Vol 32 (11) ◽  
pp. 1947-1960 ◽  
Author(s):  
Roberta Parish ◽  
Joseph A Antos

Tree-ring width chronologies of three species from a 330-year-old subalpine forest were used to reconstruct outbreaks of 2 year cycle spruce budworm (Choristoneura biennis Freeman). The growth of host species, Engelmann spruce (Picea engelmannii Parry ex Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.), was compared with that of the nonhost, lodgepole pine (Pinus contorta Dougl. ex Loud.) with and without the removal of the effects of climate on growth. Seven periods, 1989–1991, 1943–1957, 1911–1927, 1869–1875, 1839–1861, 1823–1829, 1785–1801, were identified in which the growth of both host species was reduced relative to the non-host; this includes the single known outbreak from 1944 to 1956. Spectral analysis indicated a periodicity for growth reduction of the host relative to non-host species of ca. 45 years for both spruce and fir. For three periods, the known outbreak in the 1940–1950s, and two inferred outbreaks in the 1910–1920s and 1840–1850s, we calculated the four measures of radial growth first proposed by Brubaker and Greene (L.B. Brubaker and S.K. Greene. 1979. Can. J. For. Res. 9: 95–105): the maximum rate of growth loss, 1-year and 5-year losses, and the rate and time to recovery. Growth losses were greater for fir than for spruce during all three periods. During the 1940–1950s, growth losses were severe, but losses were less in the 1910–1920s. The impact of C. biennis has varied among outbreak periods but, overall, has made a pronounced contribution to present stand conditions. Our work suggests that budworms have been a frequent agent of disturbance with major effects on forest dynamics in southern British Columbia, especially in spruce–fir forests when long periods occur between fires.

1985 ◽  
Vol 22 (4) ◽  
pp. 498-505 ◽  
Author(s):  
R. F. Miller ◽  
A. V. Morgan ◽  
S. R. Hicock

Samples of organic silt from post-Coquitlam Quadra sand at Port Moody and Mary Hill, British Columbia (dated at 18 300 and 18 700 years BP, respectively) were examined for insect remains and yielded small assemblages of beetles.At Port Moody species of the family Staphylinidae, whose members are often associated with moss or leaf litter, are the most abundant fossils present. Other specimens included open-ground beetles of the family Carabidae, as well as weevils (Curculionidae) and bark beetles (Scolytidae), which inhabit conifers. The assemblage appears to represent an open forest-floor community. Some of the species in this site have distribution ranges that do not include the Port Moody area today, but do occur in the interior of British Columbia and at higher altitude near the coast. One of the most numerous species, Micropeplus laticollis Mäklin, occurs in duff of conifers including Picea engelmannii, Abies lasiocarpa, Pinus ponderosa, and Pinus contorta. These trees are characteristic of the subalpine forest. The insect assemblage suggests an in situ deposit, subalpine in nature, probably in a cool but dry environment that developed during the short episode when this part of the Fraser Lowland was ice free between the Coquitlam and Vashon ice advances.The beetle assemblage from Mary Hill Quadra sediments probably indicates that a bog environment existed at that time; however, the lack of specific identifications precludes detailed paleoclimatic interpretation.


1979 ◽  
Vol 9 (1) ◽  
pp. 95-105 ◽  
Author(s):  
Linda B. Brubaker ◽  
Shannon K. Greene

This study compares the effects of separate Douglas-fir tussock moth (Orgiapseudotsugata McDunnough) and western spruce budworm (Choristoneuraoccidentalis Freeman) infestations on the radial growth of two host species, grand fir (Abiesgrandis (Doug.) Lindl.) and Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco). Growth records from nonhost species were also examined to substantiate that growth reduction in the hosts resulted from feeding by the respective defoliators. Ring-width data, standardized to remove trends of decreasing width from pith to bark, were tested statistically to identify significant differences in the effects of each defoliator on each host species. Four measures of radial growth were examined: maximum rate of growth decline, average rate of growth recovery, 1-year growth loss, and 5-year growth loss. The effects of tussock moth did not differ statistically between host species, but the impact of budworm defoliation on grand fir was significantly greater than on Douglas-fir. Differences occurred between the overall effects of tussock moth and budworm on the host species, with tussock moth causing significantly more rapid growth reductions and greater growth losses than budworm. It is concluded that (1) grand fir and Douglas-fir ring patterns, individually or in combination, can provide good evidence of severe defoliation by Douglas-fir tussock moth, (2) grand fir ring patterns can be used to identify severe defoliation by western spruce budworm, and (3) Douglas-fir ring patterns can provide evidence of budworm infestation only if corroborative evidence of a budworm infestation is present in the ring patterns of grand fir trees in the same stand.


2019 ◽  
Vol 15 (2) ◽  
pp. 685-700 ◽  
Author(s):  
Olga V. Churakova (Sidorova) ◽  
Marina V. Fonti ◽  
Matthias Saurer ◽  
Sébastien Guillet ◽  
Christophe Corona ◽  
...  

Abstract. Stratospheric volcanic eruptions have far-reaching impacts on global climate and society. Tree rings can provide valuable climatic information on these impacts across different spatial and temporal scales. To detect temperature and hydroclimatic changes after strong stratospheric Common Era (CE) volcanic eruptions for the last 1500 years (535 CE unknown, 540 CE unknown, 1257 CE Samalas, 1640 CE Parker, 1815 CE Tambora, and 1991 CE Pinatubo), we measured and analyzed tree-ring width (TRW), maximum latewood density (MXD), cell wall thickness (CWT), and δ13C and δ18O in tree-ring cellulose chronologies of climate-sensitive larch trees from three different Siberian regions (northeastern Yakutia – YAK, eastern Taimyr – TAY, and Russian Altai – ALT). All tree-ring proxies proved to encode a significant and specific climatic signal of the growing season. Our findings suggest that TRW, MXD, and CWT show strong negative summer air temperature anomalies in 536, 541–542, and 1258–1259 at all studied regions. Based on δ13C, 536 was extremely humid at YAK, as was 537–538 in TAY. No extreme hydroclimatic anomalies occurred in Siberia after the volcanic eruptions in 1640, 1815, and 1991, except for 1817 at ALT. The signal stored in δ18O indicated significantly lower summer sunshine duration in 542 and 1258–1259 at YAK and 536 at ALT. Our results show that trees growing at YAK and ALT mainly responded the first year after the eruptions, whereas at TAY, the growth response occurred after 2 years. The fact that differences exist in climate responses to volcanic eruptions – both in space and time – underlines the added value of a multiple tree-ring proxy assessment. As such, the various indicators used clearly help to provide a more realistic picture of the impact of volcanic eruption on past climate dynamics, which is fundamental for an improved understanding of climate dynamics, but also for the validation of global climate models.


2003 ◽  
Vol 33 (6) ◽  
pp. 1010-1028 ◽  
Author(s):  
Daniel E Ryerson ◽  
Thomas W Swetnam ◽  
Ann M Lynch

Tree-ring records were used to reconstruct spatial and temporal patterns of western spruce budworm (Choristoneura occidentalis Freeman) outbreaks in mixed conifer forests of southern Colorado. Reconstructions in 11 host stands showed a regionally synchronous pattern of at least 14 outbreaks during the past 350 years. Intervals between outbreaks were highly variable within stands, but at the regional scale outbreak intervals were more consistent. Spectral analyses of regional outbreak time series confirmed periodicities at about 25, 37, and 83 years. Comparison with an independent drought reconstruction indicated that outbreaks typically corresponded to increased moisture, while relatively little budworm activity occurred during dry periods. In contrast to other published reconstructions in Colorado and New Mexico, reconstructions from this study area did not exhibit significant 20th-century changes in the frequency of outbreak occurrence or magnitude of growth reduction. Sharply reduced growth during outbreaks was not clearly visible on the increment core samples, and budworm-induced reductions in tree-ring growth were usually detectable only after comparison with nonhost tree-ring series. This finding emphasizes that defoliation effects on ring growth can be highly relativistic. Hence, caution should be exercised in reconstructing insect outbreak histories based only on visual detection approaches, or without comparison with nonhost or nondefoliated tree-ring control series.


2020 ◽  
Vol 11 (2) ◽  
pp. 127-134
Author(s):  
Branko Stajić ◽  
Marko Kazimirović ◽  
Vojislav Dukić ◽  
Nenad Radaković

In order to assess the impact of climate variations on Austrian pine forest in the Belgrade area, the radial growth of artificially-established Austrian pine trees and its dependence on temperature and precipitation was studied using dendroclimatological methods. The site is classified as Quercetum-frainetto cerris Rudski. Standard and residual chronologies were established and several common statistics were calculated. A dendroclimatic study was carried out using the correlation and response function analysis. The Pearson correlation coefficients between the chronology indices and 13 seasonal (3-month period) precipitation and temperature data were calculated for the period from 1959 to 2014. The applied response function analysis included 24 precipitation and temperature variables from October of the prior year to September of the current year. The results of the correlation analysis pointed out that there was a strong tendency towards a positive response to the summer and late summer/early autumn precipitation and a weak significant negative response to the spring and summer temperatures. Climate-growth relationships were further first studied using the response functions for the significant seasons that were detected from the correlation analysis and then for individual months from previous October to current September. These results also highlighted the findings that higher precipitation in the current summer months has a beneficial effect on the tree-ring width. The conducted correlation between the residual chronology and the Standardised Precipitation Evapotranspiration Index indicated that a high summer value of this drought index had a positive impact on the pine growth and reinforced the previously detected relevance of September as an important month for the Austrian pine growth. These preliminary results point out that some additional climate-Austrian pine growth studies (application of various tree-ring features, growth data with a much longer time span, more sites/stands, etc.) should be performed to obtain new and valuable knowledge important for the sustainable management of Austrian pine forests.


2021 ◽  
Author(s):  
Paolo Cherubini ◽  
Giovanna Battipaglia ◽  
John L. Innes

<p>Forest health, although not yet unanimously defined, has been monitored in the past forty years assessing tree vitality, trying to estimate tree photosynthesis rates and productivity. Used in monitoring forest decline in Central Europe since the 1980s, crown foliage transparency has been commonly believed to be the best indicator of tree condition in relation to air pollution, although annual variations appear more closely related to water stress. Although crown transparency is not a good indicator of tree photosynthesis rates, defoliation is still one of the most used indicators of tree vitality. Tree rings have been often used as indicators of past productivity. However, long-term tree-growth trends are difficult to interpret because of sampling bias, and ring-width patterns do not provide any information about tree physiological processes. In the past two decades, tree-ring carbon and oxygen stable isotopes have been used  to reconstruct the impact of past climatic events, such as drought. They have proven to be useful tools for retrospectively understanding physiological processes and tree response to  stress factors. Tree-ring stable isotopes integrate crown transpiration rates and photosynthesis rates and may enhance our understanding of tree vitality. They are promising indicators of tree vitality. We call for the use of tree-ring stable isotopes in future monitoring programmes.</p>


1988 ◽  
Vol 66 (5) ◽  
pp. 963-969 ◽  
Author(s):  
Gregory A. Carter ◽  
William K. Smith

Differences in water and photosynthetic relations were compared for three codominant conifers (Engelmann spruce (Picea engelmaniï), subalpine fir (Abies lasiocarpa), and lodgepole pine (Pinus contorta) at microhabitats within a subalpine forest (central Rocky Mountains, U.S.A.) that were considered representative of different successional stages. Diumal measurements of photosynthesis, leaf conductance, and transpiration were taken at microhabitats considered early-successional (open), intermediate (forest gap), and late-successional (forest understory) environments to evaluate possible influences of gas-exchange physiology in observed distributional and successional patterns. Pine had greater water-use efficiency (photosynthesis/transpiration) in early- versus late-successional environments, primarily as a result of a lower leaf conductance and transpiration. Photosynthetic performance was similar among all three species at each respective microhabitat and increased as the openness of the microhabitat increased. Greater water-use efficiency may significantly improve the growth of pine over spruce and fir on more open, drier sites at lower elevation. Higher transpiration in spruce and fir may limit these species to higher elevation sites, to understory sites at middle elevations, and to moister open sites at lower elevations (e.g., riparian sites).


The Holocene ◽  
2018 ◽  
Vol 29 (2) ◽  
pp. 300-312
Author(s):  
Sandra Garcés-Pastor ◽  
Emilia Gutiérrez-Merino ◽  
Elisabet Martínez-Sancho ◽  
Isabel Dorado-Liñán ◽  
J Julio Camarero ◽  
...  

Understanding how climate has modulated forest growth and composition in the past is necessary to predict the influence of the ongoing climate warming on the dynamics of mountain forests. We studied the past dynamics of subalpine Pyrenean forests during the last 700 years by assessing the relationships between sedimentary pollen and tree-ring records, and their link with climatic drivers. We compared the pollen record and the montane pollen ratio, an integrative index obtained from sedimentary pollen that allows inferring past altitudinal variations in the montane–subalpine ecotone, with tree-ring width from mountain pine ( Pinus uncinata) subalpine forests located in Central Pyrenees. To assess climate–growth associations, we related the dendrochronological data with instrumental meteorological records (1901–2010) and temperature reconstructions from the Pyrenees and Northern Hemisphere. Few robust associations were found between arboreal pollen taxa and tree-ring width series of the surrounding forests. However, significant correlations were found between the montane pollen ratio and tree-ring width series from nearby forests (located less than 10 km apart). This relationship could be potentially useful to infer long-term forest growth changes at decadal to centennial scales using the montane pollen ratio. On the contrary, our results show that tree radial growth has mainly been constrained by low temperatures although the growth sensitivity to climate has considerably varied over the last 700 years. Similar results were obtained for the last century as growth variability of these high-elevation forests is still driven by low temperatures, but a relaxation of this constrain in recent decades has been detected.


2011 ◽  
Vol 41 (2) ◽  
pp. 331-340 ◽  
Author(s):  
Christof Bigler ◽  
Thomas T. Veblen

Litter and dead wood affect important processes in forest ecosystems such as nutrient and carbon cycling and are key influences on biodiversity and fire behavior. Increased tree mortality rates in western North America associated with climate trends and increased bark beetle activity highlight the need to better understand the dynamics of litter and dead wood following tree death. For eight old-growth stands in a subalpine forest landscape in northern Colorado (USA), we compared litter and dead wood loads beneath more than 200 dead and live Engelmann spruce (Picea engelmannii Parry ex Engelm.), subalpine fir (Abies lasiocarpa (Hook.) Nutt.), and lodgepole pine (Pinus contorta Douglas ex Loudon). The dynamics of litter and dead wood were analyzed using chronosequences of tree death dates over >100 years that we determined from tree rings. Immediately following tree death, high loads of litter accumulated, particularly for the biggest spruces, which accumulated 10 times more litter than live spruces (five times more for fir, two times more for pine). We estimated a higher decay rate of litter for spruce (half-life of four years) than for pine (15 years) and fir (19 years). The accumulation rates for dead wood following tree death were highly variable among trees, but maximum accumulation was attained during the first 50–60 years.


1999 ◽  
Vol 29 (10) ◽  
pp. 1583-1591 ◽  
Author(s):  
Cornelia Krause ◽  
Hubert Morin

Radial growth along the stems and root systems of black spruce trees (Picea mariana (Mill.) BSP) was examined to determine the effects of spruce budworm defoliation. A mixed conifer and pure black spruce stand located in the boreal zone of Quebec, Canada were sampled. Following defoliation, dendrochronological analyses revealed the percent growth reduction in the ring width at different stem heights and throughout the root system. Ring widths of black spruce were found to be reduced during the last three spruce budworm outbreaks. The reduction of the tree-ring width after spruce budworm outbreaks started first in the crown region and was followed by reduction at the stem base. For the whole root system, the ring-width index exhibited a decrease. The root system showed a high sensitivity to defoliation by spruce budworm. Inside the root system, the growth reduction after a spruce budworm outbreak was variable in each root branch. The growth decrease of the pure black spruce stand was less intensive than in the mixed stand.


Sign in / Sign up

Export Citation Format

Share Document