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1
Akkemik, Ünal. "Dendroclimatology of Umbrella Pine (Pinus pinea L.) in Istanbul, Turkey." Tree-Ring Society, 2000. http://hdl.handle.net/10150/262533.
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To determine the response of tree rings to climate, twenty cores were extracted from ten trees of Pinus pinea L. in Istanbul-Alemdag. A response function was used to characterize the relationships between tree rings and temperature and precipitation. The precipitation of the current year and the temperature at the beginning of the growing period have a significantly positive influence on the growth of the tree ring. Mean sensitivity was found to be 0.291, and it was concluded that Pinus pinea L. is a dendroclimatologically sensitive species.
2
Hallman, Christine, Tom Harlan, and Howard Arnott. "Lost and Found: the Bristlecone Pine Collection." Tree-Ring Society, 2006. http://hdl.handle.net/10150/262622.
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3
Richter, K., D. Eckstein, and R. L. Holmes. "The Dendrochronological Signal of Pine Trees (Pinus Spp.) in Spain." Tree-Ring Society, 1991. http://hdl.handle.net/10150/262302.
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Thirty-one old-age pine stands in nine mountainous regions of Spain were studied in order to delineate dendrochronologically uniform areas. A country-wide cross-correlation analysis of the autoregressively standardized site chronologies showed the dendrochronological signal decreasing with distance so that beyond about 450 km crossdating becomes less reliable, but even over 630 km, the correlation coefficient is sometimes significantly high. A principal components analysis of the variance among the site chronologies segregated the chronologies into a northern and a southern group roughly along a line from Madrid to Barcelona. Two low-elevation northern sites were grouped with the southern sites. Moisture supply limits the growth of the pines in this group. In contrast, the high-elevation northern sites do not suffer from prolonged droughts. According to the uniform and extensive tree-ring signal in the south of the peninsula, the potential of dendrochronology for dating cultural objects is predicted to be favorable. Because of the greater variability between sites in the north, further studies are necessary to delineate uniform areas.
4
Heyerdahl, Emily K., and Steven J. McKay. "Condition of Live Fire-Scarred Ponderosa Pine Trees Six Years after Removing Partial Cross Sections." Tree-Ring Society, 2001. http://hdl.handle.net/10150/251619.
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Our objective was to document the effect of fire-history sampling on the mortality of mature ponderosa pine trees in Oregon. We examined 138 trees from which fire-scarred partial cross sections had been removed five to six years earlier, and 386 similarly sized, unsampled neighbor trees, from 78 plots distributed over about 5,000 ha. Mortality was low for both groups. Although mortality was significantly higher for the sectioned trees than their neighbors (8% versus 1 %), removing a partial section did not appear to increase a tree's susceptibility to death from factors such as wind or insect activity. Specifically, the few sectioned stems that broke did so well above sampling height. Most sectioned trees (79 %) had evidence of insect activity in 1994/95, while only an additional 5% had such evidence in 2000. Mortality among sectioned trees in this study was low probably because we removed relatively small sections, averaging 7 cm thick and 8% of the tree's cross-sectional area, from large trees of a species with effective, resin-based defenses against insects and pathogens. Sampling live ponderosa pine trees appears to be a non-lethal method of obtaining information on past fire regimes in this region because it only infrequently led to their death in the early years after sampling.
5
Génova, Ricardo. "Dendroclimatology of Mountain Pine (Pinus uncinata Ram.) in the Central Plain of Spain." Tree-Ring Society, 1986. http://hdl.handle.net/10150/261683.
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Few dendrochronological studies have been carried out in Spain or Portugal. Mountain pine (Pinus uncinata Ram.) may be especially suitable for investigation because of its broad altitudinal range and great age. Samples from a site in the Sierra de Cebollera were prepared and dated using several cross-dating techniques. The dated series were used to develop a ring-width index chronology that was compared with local climate data. Ring-width variability is related to precipitation, but temperature can also be important, indicating a complex climate response. Future studies of this species will be important for dendroclimatology and for study of ecophysiology of subalpine plants in the Mediterranean area.
6
Hudson, Laura Elizabeth. "Limber pine sensitivity to climatic and biological stressors evidence from dendrochronology and carbon isotopes /." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1495959111&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Despain, Del Westover. "Radial Growth Relationships in Utah Juniper (Juniperus Osteosperma) and Pinyon Pine (Pinus Edulis)." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184705.
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The assumption that each latewood ring in trees represents one year of growth was tested for Utah juniper (Juniperus osteosperma) and pinyon pine (Pinus edulis). Ring characteristics and growth rates were evaluated for 72 years of growth following scars of consistent date on all trees sampled. Errors in age and growth rate estimates based on ring counts were evaluated. Potential variation among observers was accounted for. Average error in ring counts was lowest when rings were counted on the fastest-growing portions of each cross-section. Errors for more than 40% of the junipers exceeded 10 percent with about half of the trees with more rings and half with less rings than actual years. Pinyons rarely had more rings than years and only 5% of the trees were missing more than 10% of the 72 annual rings. Percentage errors in growth rate estimates based on ring counts were similar to ring count errors for both species. Assigning junipers to age classes based on ring counts also can lead to error in assumed ages of trees. Assuming that ring count error for each tree for the 72 year period studied approximates potential error over the life of each tree, more than half of junipers older than 250 years would be assigned to the wrong age class when using 50 year age classes. Number of rings in junipers was highly correlated with growth rate. Competition from surrounding trees explained as much as 53% and 40% of the variation in growth rates of junipers and pinyons respectively. Relating growth rates and ring counts to ordinations of stand, site and soil characteristics indicated that trees with relatively fast growth rates or trees with the most rings tended to occur on gentle, north to northeast aspects with relatively better- developed soils. However, stand competition often had an overriding influence on growth. Presence of Koelaria pyramidata in the understory was generally an indicator of relatively favorable growing conditions for junipers. Results suggest the need for more caution in the use of ring counts for estimating ages or growth rates of Utah junipers and pinyons than has generally been used in the past, especially when drawing conclusions about specific individuals.
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Brown, Peter M., Amalava Bhattacharyya, and Santosh K. Shah. "Potential For Developing Fire Histories In Chir Pine (Pinus Roxburghii) Forest In The Himalayan Foothills." Tree-Ring Society, 2011. http://hdl.handle.net/10150/622625.
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We report on the potential for developing long-term fire histories from chir pine (Pinus roxburghii Sarg.) forests in the Western Himalayan foothills based on a preliminary study from a stand located in the state of Uttarakhand in northern India. Rings from trees collected to develop a master skeleton plot chronology were generally complacent with false rings present during most years, but were crossdatable with only minor difficulty. The oldest tree confidently crossdated back to 1886, with good sample depth (5 trees) from 1911, which helped date the fire scars in cross-sections collected from three trees. Fire frequency as determined from fire-scar dates was high, with mean and median fire intervals of 3 years from 1938 to 2006. Fires were likely from human ignitions given the prevalence of human land use in the site. Fire scars were generally recorded at false-ring boundaries and likely represent burning during the hot, dry period in May or early June before the onset of monsoon rainfall beginning in mid-June. Although only three fire-scarred trees were sampled, this preliminary assessment shows there is a potential for additional samples from other stands to develop longer-term fire histories to better understand the role of fire in the ecology and management of chir pine throughout its range in the Himalaya region.
9
Stanton, Sharon. "Effects Of Dwarf Mistletoe On Climate Response Of Mature Ponderosa Pine Trees." Tree-Ring Society, 2007. http://hdl.handle.net/10150/622558.
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This research examines the influence of western dwarf mistletoe (Arceuthobium campylopodum)
infection on the radial growth response of mature ponderosa pines (Pinus ponderosa) and its effects on dendroclimatic reconstructions. I hypothesize that trees with mistletoe have lower annual growth rates than uninfected trees, but exhibit higher mean sensitivities and stronger relationships between growth and climate variation. I tested these hypotheses using correlation and regression analyses to compare 100-year crossdated and standardized tree-ring chronologies from 26 infected and 29 uninfected trees. I compared both chronologies to climate variation as measured by changes in total precipitation, minimum, mean, and maximum temperature, and the Palmer Drought Severity Index (PDSI). Results show that trees infected with dwarf mistletoe have higher radial growth rates, exhibit greater sensitivity, and respond more strongly to climate variation. Both infected and uninfected chronologies are significantly correlated with the respective climate variables, but exhibit different patterns. The strongest correlations are between infected trees and PDSI for all months tested; significant correlations between uninfected trees and PDSI are limited to May through December lagged from the
previous year. These results suggest mistletoe-infected trees are more sensitive to climatic factors than uninfected trees and may be useful for dendroclimatic analyses.
10
Campbell, Rochelle, Danny McCarroll, Iain Robertson, Neil J. Loader, Håkan Grudd, and Björn Gunnarson. "Blue Intensity In Pinus Sylvestris Tree Rings: A Manual For A New Palaeoclimate Proxy." Tree-Ring Society, 2011. http://hdl.handle.net/10150/622639.
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Minimum blue intensity is a reflected light imaging technique that provides an inexpensive, robust and reliable surrogate for maximum latewood density. In this application it was found that
temperature reconstructions from resin-extracted samples of Pinus sylvestris (L.) from Fennoscandia provide results equivalent to conventional x-ray densitometry. This paper describes the implementation of the blue intensity method using commercially available software and a flat-bed scanner. A calibration procedure is presented that permits results obtained by different laboratories, or using different scanners, to be compared. In addition, the use of carefully prepared and chemically treated 10-mm-diameter cores are explored; suggesting that it may not be necessary to produce thin laths with the rings aligned exactly perpendicular to the measurement surface.
11
Speer, James H., and Richard L. Holmes. "Effects of Pandora Moth Outbreaks on Ponderosa Pine Wood Volume." Tree-Ring Society, 2004. http://hdl.handle.net/10150/262634.
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Coloradia pandora (Blake) is a phytophagous insect that defoliates Pinus ponderosa (Dougl. ex Laws.) in south-central Oregon. Little is known about the extent of damage this insect inflicts upon its host trees during an outbreak. In this paper, we present stem analyses on four dominant Pinus ponderosa trees that enable us to determine the amount of volume lost during each Coloradia pandora outbreak on this site for the past 450 years. We found that on average an outbreak inhibits radial growth so that an individual tree produces 0.057 m³ less wood volume than the potential growth for the duration of an individual outbreak. A total of 0.549 m³ of growth per tree was inhibited by 10 outbreaks during the lifetime of the trees, which, in this stand, equates to 9.912 m³/ha (1,700 board feet/acre) of wood suppressed over the last 450 years throughout the stand. Our results do not support previous findings of a lag in suppression onset between the canopy of the tree versus the base. Crossdating of stem analysis samples is paramount to definitively examine the potential for a lagged response throughout the
12
Kilgore, Jason S., and Frank W. Telewski. "Climate-Growth Relationships for Native and Nonnative Pinaceae in Northern Michigan's Pine Barrens." Tree-Ring Society, 2004. http://hdl.handle.net/10150/262632.
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Secondary growth responses of native and nonnative trees exposed to the same climatic conditions can elucidate sensitivities and thus adaptability to a particular region. A long-term mixed-species planting in the pine barrens of northern lower Michigan presented an opportunity to discriminate responses from species commonly planted in this region. Mean ring-width chronologies from living native Pinus resinosa Ait. and P. strobus L. and nonnative P. sylvestris L. and Picea abies (L.) Karst. at this plantation were generated, standardized, and analyzed by correlation analysis against mean monthly climatic variables. The native pine chronologies had the highest mean ring widths and signal-to-noise ratios (SNR), were highly correlated to each other, and exhibited positive responses to years with above-normal April temperatures but no significant relationships to variations in precipitation. The P. sylvestris chronology was highly correlated to the other two pine chronologies and responded similarly to April temperatures but exhibited negative correlations to January and April precipitation and positive correlations to September precipitation. The P. abies chronology had the highest mean sensitivity and was correlated with the P. strobus chronology but only responded positively to precipitation from the previous December. The low SNR (P. sylvestris, P. abies), high mean sensitivity (P. abies), and larger number of significant correlations to variations in monthly climatic variables (P. sylvestris) suggest that these nonnative species are more sensitive to this local climate. These results provide insights to the adaptability, establishment, and geographic distribution of the nonnative Pinaceae.
13
Wight, Georgina DeWeese, and Henri D. Grissino-Mayer. "Dendrochronological Dating of an Antebellum Period House, Forsyth County, Georgia, U.S.A." Tree-Ring Society, 2004. http://hdl.handle.net/10150/262616.
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We examined tree rings from cross-sections of shortleaf pine (Pinus echinata Mill.) timbers extracted from a house in Forsyth County, Georgia, that was reportedly built in the mid-19th Century during the Antebellum Period (pre-1860). Our goals were to (1) determine the probable construction year for the house to help assess its possible historical significance, and (2) create a new long-term reference chronology for the northern Georgia area where such chronologies are lacking. Sections of shortleaf pine were removed from the structure during a renovation project in 2001. Sixteen sections were used to build a floating tree-ring chronology 217 years in length from series that crossdated conclusively with other series both graphically via skeleton plots and statistically via COFECHA. We then statistically evaluated the probable absolute temporal placement of this chronology using several regional tree-ring chronologies from the southeastern U.S. A statistically significant (p , 0.0001) correlation between our chronology and a shortleaf pine chronology from Clemson, South Carolina, anchors our chronology between 1652–1868. Two missing rings are probable in the early portion of our chronology, but we currently do not have a sufficient number of samples to conclusively identify their exact placement. No cluster of outermost rings was found to support the reported construction date of 1851, although the outermost rings on 13 of 16 samples dated before 1851. This new chronology could aid further dating of wood from archaeological sites and historical structures, and establish an initial data set that could eventually provide important new insights about the climate of northern Georgia during the 17th–19th Centuries.
14
Harley, Grant L., Henri D. Grissino-Mayer, and Sally P. Horn. "The Dendrochronology Of Pinus Elliottii In The Lower Florida Keys: Chronology Development And Climate Response." Tree-Ring Society, 2011. http://hdl.handle.net/10150/622627.
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South Florida slash pine (Pinus elliottii var. densa) is the southernmost pine species in the United States and the foundation species of the globally endangered pine rockland communities in south Florida. To test if slash pine produces annual growth rings in the Lower Florida Keys, we counted the number of rings on samples collected from the North Big Pine Key site (NBP), which contained a fire scar from a known wildfire and a known date for hurricane-induced tree mortality (2006 or 2007). In addition, a crossdated tree-ring chronology (1871–2009) was developed from living trees and remnant wood found at the site and compared to divisional climate data to determine how the regional climate regime influences radial growth. Our analyses demonstrated that slash pine forms anatomically distinct, annual growth rings with the consistent year-to-year variability necessary for rigorous dendrochronological studies. Response-function and correlation analysis showed that annual growth of slash pine at NBP is primarily influenced by water availability during the growing season. However, no significant correlations were found between tree growth and the Atlantic Multidecadal Oscillation or the El Niño-Southern Oscillation. Our study reveals the potential of producing high-quality dendrochronological data in southern Florida from slash pine, which should prove useful in further studies on fire history and tree phenology and for assessing the projected impacts of impending climate change on the fragile pine rockland community.
15
Bale, Roderick Jon. "Climatic reconstruction of the last 1000 years from bristlecone pine tree rings at Blanco, White Mountains, California, USA." Thesis, Swansea University, 2008. https://cronfa.swan.ac.uk/Record/cronfa42975.
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As the first decade of the 21st century draws to a close, a key issue facing humanity is that of climate change. Understanding past climate should improve future predictions and climate models. Stable isotope ratios from tree rings may be free from some of the problems associated with tree ring width studies. This research creates a millennial (AD1005-2005) annually resolved δ¹³C based temperature and precipitation reconstruction from bristlecone pine trees growing at an elevation of c.3000m at Blanco in the White Mountains of south central California. Samples were cross dated, cut into annual increments and extracted to α-cellulose. Following this measurements of δ¹³C were made. The δ¹³C results were corrected for increasing atmospheric δ¹²C concentration due to fossil fuel combustion (δ¹³Ccor), and for increasing CO₂ over the last 150 years (δ¹³Cpin). Summer temperature and precipitation are demonstrated to influence δ¹³C ratios. Annual δ¹³C fluctuations correlate strongly with summer precipitation, while lower frequency variations appear to follow changes in summer temperature. The mid 12th, late 16th, late 17th and early 18th century appear to have been warmer, or drier than the 20th century. The late llth/early 12th, early 15th, early 17th and late 19th centuries appear to have witnessed wetter or colder periods than the 20th century. The data compares favourably with previous climate reconstructions from the Western United States.
16
Helama, Samuli, Markus Lindholm, Jouko Meriläinen, Mauri Timonen, and Matti Eronen. "Multicentennial Ring-Width Chronologies of Scots Pine Along a North-South Gradient Across Finland." Tree-Ring Society, 2005. http://hdl.handle.net/10150/262617.
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Four regional Scots pine ring-width chronologies at the northern forest-limit, and in the northern, middle and southern boreal forest belts in Finland cover the last fourteen centuries. Tree-ring statistics and response functions were examined, and tree-ring width variation was also compared to North Atlantic Oscillation (NAO) and volcanic forcing. The tree-ring statistics show evidence of an ecogeographical gradient along a north-south transect. The three northernmost regional chronologies share a positive response to mid-summer temperature, and all four chronologies show positive and significant correlation to early-summer precipitation. Moreover, a positive and significant relationship to winter NAO was detected in three out of four regional chronologies. NAO also drives the common (inter-regional) growth variability. Years of known cool summers caused by volcanic forcing exhibit exceptionally narrow tree rings in the three northernmost regional chronologies.
17
Biondi, Franco, and Fares Qeadan. "A Theory-Driven Approach To Tree-Ring Standardization: Defining The Biological Trend From Expected Basal Area Increment." Tree-Ring Society, 2008. http://hdl.handle.net/10150/622585.
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One of the main elements of dendrochronological standardization is removing the biological
trend, i.e. the progressive decline of ring width along a cross-sectional radius that is caused by the corresponding increase in stem size and tree age over time. The ‘‘conservative’’ option for removing this biological trend is to fit a modified negative exponential curve (or a straight line with slope ≤ 0) to the ring-width measurements. This method is based on the assumption that, especially for open-grown and/or shade-intolerant species, annual growth rate of mature trees fluctuates around a specific level, expressed by a constant ring width. Because this method has numerical and conceptual drawbacks, we propose an alternative approach based on the assumption that constant growth is expressed by a constant basal area increment distributed over a growing surface. From this starting point, we derive a mathematical expression for the biological trend of ring width, which can be easily calculated and used for dendrochronological standardization. The proposed C-method is compared to other standardization techniques, including Regional Curve Standardization (RCS), of tree-ring width from ponderosa pines (Pinus ponderosa Douglas ex P.Lawson & C.Lawson) located at the Gus Pearson Natural Area (GPNA) in northern Arizona, USA. Master ring-index chronologies built from ring area, RCS, and C-method reproduced stand-wide patterns of tree growth at the GPNA, whereas other standardization options, including the ‘‘conservative’’ one, failed to do so. In addition, the C-method has the advantage of calculating an expected growth curve for each tree, whereas RCS is based on applying the same growth curve to all trees. In conclusion, the C-method replaces the purely empirical ‘‘conservative’’ option with a theory based approach, which is applicable to individual ring-width measurement series, does not require fitting a growth curve using nonlinear regression, and can be rigorously tested for improving tree-ring records of environmental changes.
18
Woodall, C. W. "When Is One Core Per Tree Suffifcient To Characterize Stand Attributes? Results Of A Pinus Ponderosa Case Study." Tree-Ring Society, 2008. http://hdl.handle.net/10150/622568.
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Increment cores are invaluable for assessing tree attributes such as inside bark diameter, radial
growth, and sapwood area. However, because trees accrue growth and sapwood unevenly around their pith, tree attributes derived from one increment core may not provide sufficient precision for forest management/research activities. To assess the variability in a tree’s inside bark radius, sapwood radius, and 10-year radial growth estimated by tree cores, two increment cores at 90 degree angles were collected from ponderosa pine (Pinus ponderosa) trees in eastern Montana (n = 2,156). Paired core measurements varied substantially with 13% mean difference for inside bark radius, 19% mean difference for sapwood radius, and 23% mean difference for estimates of radial increment. Furthermore, decreasing crown ratio, decreasing diameter, and increasing site slope were all found to increase differences in estimates derived from paired cores. Whether for management or research purposes, the number of cores that should collected per tree depend on a stand’s susceptibility to reaction wood, required measurement precision, and budgetary constraints.
19
Perkins, Dana Lee. "Ecology of Treeline Whitebark Pine (Pinus albicaulis) Populations in Central Idaho: Successional Status, Recruitment, and Mortality, and A Spring Temperature Reconstruction from Whitebark Pine Tree Rings." DigitalCommons@USU, 2001. https://digitalcommons.usu.edu/etd/6591.
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T his research investigated the successional status of treeline whitebark pine (Pinus albicaulis) populations on 14 stands in central Idaho and used empirical statistical models to determine the principal factors affecting recruitment and mortality. The longest lived whitebark pines from four additional high-elevation sites were used to develop a tree-ring chronology to reconstruct over 1,000 years of average April-May temperature.
The assessment of stand structures using size-frequency distributions generally provides evidence that treeline whitebark pine populations are currently self-sustaining in areas of low to nonexistent incidence of white pine blister rust (Cronartium ribicola). However the presence of subalpine fir (Abies lasiocarpa) in all size classes on sample plots suggests potential replacement of, or codominant climax with whitebark pine.
Inference from Poisson regression models suggests that stand structure variables are important to whitebark pine establishment, which may be constrained by interference competition and available growing space. Subalpine fir establishment appears to be constrained by distance to seed source at lower elevations and by favorable site water-balance effects on northly aspects.
Inferences from logistic regression models calibrated from pre-epidemic stand conditions and post-epidemic mortality levels surrounding a historic mountain pine beetle (Dendroctonus ponderosae) outbreak suggest that density and tree size variables are significant predictors of stand and individual tree attack. The significance of the predictor variables in these models corroborates the susceptible host characteristics identified in other pine-mountain pine beetle system risk assessments.
A composite whitebark pine tree-ring chronology from 24 trees from four sites was used to develop a 1028-year long reconstruction of spring temperature for the Sawtooth-Salmon River region of central Idaho. The chronology was calibrated against Ketchum and New Meadows, Idaho US Historical Stations, April-May average monthly temperature using half-sample calibration-verification tests for the period that contained historic climate data, 1909-1992. The chronology accounted for 41% of the variability in the climatic data and successfully simulated medium to high frequency trends. A 19th century cold period coincides with the "Little Ice Age." Neither the instrumental nor the proxy temperature records show evidence of warming in the 20th century.
20
Ballesteros, J. A., M. Stoffel, J. M. Bodoque, M. Bollschweiler, O. Hitz, and A. Díez-Herrero. "Changes In Wood Anatomy In Tree Rings Of Pinus Pinaster Ait. Following Wounding By Flash Floods." Tree-Ring Society, 2010. http://hdl.handle.net/10150/622618.
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This paper analyzes the anatomical response of Pinus pinaster Ait. following wounding by flash
floods. A total of 14 wood samples were taken from 14 different scarred trees located on the river banks of the Arroyo Cabrera torrent (Spanish Central System). In addition, 20 increment cores were collected from undisturbed and healthy P. pinaster trees to build a local reference chronology. For the injured trees, analysis focused on growth changes in early earlywood (EE) tracheids, namely on differences in (i) lumen size; (ii) cell-wall percentage and cell-wall thickness; (iii) radial length and tangential width of tracheids; as well as (iv) in the abundance of resin ducts in earlywood (EW) and latewood (LW) following wounding. Results indicate that tissues bordering flash-flood wounds are characterized by reduced growth rates and a decrease of EE tracheid lumen area by 51%. In addition, cell-wall percentage increases by 34% in the increment rings formed after the event and significant changes are observed in the radial length and tangential width of EE tracheids. Observations on resin ducts do not yield any significant
results. Based on these anatomical parameters, detecting and dating past flash-flood events in growth rings is now possible for Mediterranean species, specifically P. pinaster.
21
Rydval, Miloš. "Dendroclimatic reconstruction of late Holocene summer temperatures in the Scottish Highlands." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/8418.
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This thesis focuses on reconstructing past temperatures using Scots pine (Pinus sylvestris L.) tree-ring chronologies developed from Scotland. The research aims to fill a spatial and temporal gap in understanding northwest European climate dynamics, thus providing the context for assessing future climate changes in this region. Development of both a spatially complete reconstruction from an extensive network of 44 'living' Scottish tree-ring chronologies for the last few centuries, but also a near-millennium length chronology from central Scotland using mainly lake-derived 'subfossil' wood material was undertaken. Before reconstruction development, a combination of treegrowth modelling and disturbance removal methodologies was utilised in order to understand the drivers of pine growth in the Scottish Highlands, and to assess and remove anthropogenic disturbance and other non-climatic influences on growth. The advantages and limitations of utilising the relatively new 'Blue Intensity' (BI) parameter was also explored and assessed, particularly in relation to its possible utilization as a more affordable surrogate for maximum latewood density in the development of temperature reconstructions and for crossdating validation of undated samples. Although BI showed much promise for dendroclimatology, elimination of low frequency biases resulting from sample discolouration still requires further attention. Chronologies from the Cairngorms in central Scotland were identified as most suitable for reconstruction development, while reconstructions based on chronologies from other areas in the west were found to be weaker due to a range of factors including disturbance. In order to maximise reconstruction strength, BI and ring width (RW) data were combined to produce composite high-frequency BI / low-frequency RW chronologies. Although it was possible to develop an ~800 year reconstruction of temperature from central Scotland, there is substantial potential to further extend this reconstruction back in time.
22
Heyerdahl, Emily K., and Steven J. McKay. "Condition Of Live Fire-Scarred Ponderosa Pine Eleven Years After Removing Partial Cross-Sections." Tree-Ring Society, 2008. http://hdl.handle.net/10150/622566.
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Our objective is to report mortality rates for ponderosa pine trees in Oregon ten to eleven years
after removing a fire-scarred partial cross-section from them, and five years after an initial survey of post-sampling mortality. We surveyed 138 live trees from which we removed fire-scarred partial crosssections in 1994/95 and 387 similarly sized, unsampled neighbor trees of the same species. These trees were from 78 plots distributed over about 5,000 ha at two sites in northeastern Oregon. The annual mortality rate for sectioned trees from 1994/95 to 2005 was 3.6% compared to 2.1% for the neighbor trees. However, many of the trees that died between 2000 and 2005 were likely killed by two prescribed fires at one of the sites. Excluding all trees in the plots burned by these fires (regardless of whether they died or not), the annual mortality rate for sectioned trees was 1.4% (identical to the rate from 1994/95 to 2000) compared to 1.0% for neighbor trees. During these fires, a greater proportion of sectioned trees died than did catfaced neighbor trees (80% versus 64%) but the difference was not significant.
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De, Schutter Alice, and Karin Markendahl. "Using blue light reflectance from high-resolution images (6000 dpi) of Scots pine tree rings to reconstruct three centuries of Scottish summer temperatures." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297369.
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Advances in scanner technology have made it possible to obtain high resolution (6000 dpi) images of tree samples. Due to the images’ increased capability of resolving anatomical wood structures, the new technology could be of benefit to dendroclimatology. This study attempts to expand on Rydval et al.’s (2017) previous 800 years reconstruction of Scottish summer temperatures by assessing whether a higher image resolution of samples has the ability to improve the accuracy of the region’s temperature reconstruction. Two independent blue intensity (BI) chronologies, based on differing image resolutions (6000 dpi and 2400 dpi) of Scots pine samples, were developed and subjected to standard detrending procedures. Raw data from Rydval et al.’s (2017) prior study was used to develop the chronology which was based on the 2400 dpi images. On the other hand, newly acquired data was utilized for the other chronology. In order to resolve the primary question that this paper explores, the characteristics and strength of the two BI chronologies’ climatic signals were compared. In addition, the newly acquired data was used to develop a 318 years reconstruction of mean July/August temperatures for Scotland. Calibrations against meteorological data indicated that the improved image resolution did not generate a positive effect on the chronology’s ability to retain a reliable climatic signal. The study’s findings were thus inconclusive in showing that a higher image resolution of Scots pine samples improves the accuracy of temperature reconstructions for Scotland. Future studies are encouraged to investigate the applicability of dendroclimatic computer softwares (i.e. CooRecorder) with regard to a high image resolution. From a broader perspective, this study contributes to setting climate change in a more accurate long term spatiotemporal context. This is crucial in predicting future climate variability, as well as understanding the role and extent of anthropogenic forcing.<br>Framsteg inom skannerteknik har gjort det möjligt att få bilder av trädprover med hög upplösning (6000 dpi). På grund av bildernas ökade förmåga att lösa anatomiska träd strukturer kan den nya tekniken vara till nytta för dendroklimatologi. Denna studie strävar mot att utveckla Rydval et al.s (2017) tidigare 800 års rekonstruktion av skotska sommartemperaturer genom att bedöma om en högre bildupplösning av prover har förmågan att förbättra noggrannheten för regionens temperaturrekonstruktion. Två oberoende blåintensitet (BI) -kronologier, baserade på olika bildupplösningar (6000 dpi och 2400 dpi) av skotska träprover, framtogs och utsattes för standardförfaranden. Rådata från Rydval et al.s (2017) tidigare studie användes för att utveckla kronologin som baserades på 2400 dpi-bilderna. Å andra sidan användes nyförvärvade data för den andra kronologin. För att besvara den primära frågan som denna studie undersöker jämfördes egenskaperna och styrkan hos de två BI-kronologins klimat signaler. Dessutom används de nyförvärvade uppgifterna för att utveckla en 318 års rekonstruktion av genomsnittliga juli/augusti temperaturer för Skottland. Kalibreringar mot meteorologiska data indikerade att den förbättrade bildupplösningen inte genererade en positiv effekt på kronologins förmåga att behålla en pålitlig klimat signal. Studiens resultat var således otvetydiga när de visade att en högre bildupplösning av skotsk tallprover förbättrar noggrannheten i temperatur rekonstruktioner för Skottland. Framtida studier uppmuntras att undersöka användbarheten av dendroklimatiska datorprogram (dvs CooRecorder) med avseende på en ultrahög bildupplösning. Ur ett bredare perspektiv bidrar denna studie till att placera klimatförändringarna i ett mer exakt långsiktigt rumsligt tidsmässigt sammanhang. Detta är avgörande för att förutsäga framtida klimatvariationer samt förstå rollen och omfattningen av antropogen tvingande.
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Bhuta, Arvind A. R., Lisa M. Kennedy, and Neil Pederson. "Climate-Radial Growth Relationships Of Northern Latitudinal Range Margin Longleaf Pine (Pinus Palustris P. Mill.) In The Atlantic Coastal Plain Of Southeastern Virginia." Tree-Ring Society, 2009. http://hdl.handle.net/10150/622605.
Full textAbstract:
Climate and longleaf pine (Pinus palustris P. Mill.) radial growth relationships have been
documented within its southern and western distribution. However, knowledge of this relationship is lacking along its northern latitudinal range margin (NLRM). Based on the principles of ecological amplitude, limiting factors, and studies of coniferous species in eastern temperate forests of the U.S., we hypothesized that the radial growth of longleaf pine in mixed pine-hardwood forests is responding to winter temperatures in southeastern Virginia. Two longleaf pine chronologies were developed to determine the relationship between radial growth and monthly temperature, precipitation, and Palmer Drought Severity Index (PDSI) via response function analysis (RFA). Results at the 0.05 level yielded significant response function coefficients with a positive response to current winter temperature and precipitation and a negative response to prior August PDSI. In studies of climate and longleaf pine radial growth in other parts of its range, winter temperature and precipitation have not shared a significant positive association with radial growth. Instead current spring and summer precipitation usually share this positive association. These findings add more evidence to an emerging pattern suggesting that winter temperatures contribute to limiting the radial growth of temperate conifers at northern range margins in the Northern Hemisphere.
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Van, De Gevel Saskia L., Justin L. Hart, Henri D. Grissino-Mayer, and Kenneth W. Robinson. "Tree-Ring Dating Of Old-Growth Longleaf Pine (Pinus Palustris Mill.) Logs From An Exposed Timber Crib Dam, Hope Mills, North Carolina, U.S.A." Tree-Ring Society, 2009. http://hdl.handle.net/10150/622604.
Full textAbstract:
On 26 May 2003, intense rainfall from a series of thunderstorms in eastern North Carolina
caused flooding that eventually destroyed the concrete dam in Hope Mills, draining Hope Mills Lake, and revealing a formerly submerged and buried structure that was identified as a timber crib dam. Inspection revealed these logs to be old-growth longleaf pines, which are now rare on the coastal plain landscape. Our primary objective was to develop a new multi-century longleaf pine tree-ring chronology by crossdating the tree rings from sections extracted from logs in the crib dam with an anchored tree-ring chronology created from nearby living longleaf pine trees. We also examined the climatic response in the longleaf pine trees to evaluate their potential for reconstructing climate. Using tree-ring measurements obtained from old-growth longleaf pines found at a nearby church, we were able to date the rings on 21 series representing 14 logs from the crib dam, spanning the years 1597 to 1825. Distorted sapwood in many of the logs prevented us from finding absolute cutting dates and lessened the strength of correlation during the period of overlap between the church series and crib dam series. Human disturbances, specifically related to the naval stores industry, likely influenced the growth-ring patterns of the crib dam pine samples, as well. Correlation analyses between the longleaf pine chronology and temperature, precipitation, Palmer Drought Severity Indices, and North Atlantic sea surface temperatures showed a significant response to cool and wet spring months.
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Pepper, David A. "Investigation of the long term physiological response of Huon pine (Lagarostrobos franklinii) to changes in atmospheric CO2 and climate using stable isotopes." Connect to full text, 1999. http://ses.library.usyd.edu.au/handle/2123/4032.
Full textAbstract:
Thesis (Ph. D.)--University of Sydney, 2000.<br>Title from title screen (viewed February 12, 2009). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Biological Sciences, Faculty of Science. Degree awarded 2000; thesis submitted 1999. The 2 in the title is in subscript. Includes bibliographical references. Also available in print form.
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Pepper, David A. "Investigation of the long term physiological response of Huon pine (Lagarostrobos franklinii) to changes in atmospheric CO2 and climate using stable isotopes." Phd thesis, School of Biological Sciences, 1999. http://hdl.handle.net/2123/4032.
Full textAbstract:
Thesis (Ph. D.)--University of Sydney, 2000.<br>Title from title screen (viewed February 12, 2009). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Biological Sciences, Faculty of Science. Degree awarded 2000; thesis submitted 1999. The 2 in the title is in subscript. Includes bibliographical references. Also available in print form.
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Klinka, Karel, Bernhard E. Splechtna, Jaroslav Dobry, and Christine Chourmouzis. "Climate - radial growth relationships in some major tree species of British Columbia." Forest Sciences Department, University of British Columbia, 1998. http://hdl.handle.net/2429/671.
Full textAbstract:
This study examines the influence of climate on tree-ring properties of several major tree species: Pacific silver fir (Abies amabilis (Dougl. ex Loud.) Forbes), subalpine fir (Abies lasiocarpa (Hook.) Nutt.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and lodgepole pine (Pinus contorta var. latifolia Dougl. ex Loud.). Our three objectives were to determine how (1) tree-ring properties change along an elevation gradient, (2) short-term climatic influences are correlated with tree-ring properties, and (3) long-term climatic influence on tree-ring properties.
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Biondi, Franco. "Development of a Tree-Ring Network for the Italian Peninsula." Tree-Ring Society, 1992. http://hdl.handle.net/10150/262358.
Full textAbstract:
This article describes the analysis of tree-ring collections from standing trees of sixteen species at twenty sites distributed throughout the Italian Peninsula. Visual and numerical crossdating among ring widths allowed the computation of standard and residual tree-ring chronologies. Relationships among chronologies were identified by Spearman's coefficient of rank correlation, using Bonferroni's inequality to adjust significance level. The oldest living tree sampled to date is a 963-year old palebark pine (Pinus leucodermis Ant.) at Parco del Pollino. Individuals more than two centuries old were identified at eleven sites for eight species. The tree-ring network so far consists of twenty-two chronologies for nine species at nineteen sites. Seven conifer species account for ten chronologies and two angiosperm species account for the remaining twelve chronologies. The most represented species is Fagus sylvatica L., with eleven chronologies distributed over the entire peninsula and highly correlated with one another. The order of autoregressive models fitted to the data never exceeded two. In particular, the order of autoregressive models fitted to Fagus sylvatica chronologies decreased with decreasing age of sampled trees. Based on the significant coefficients of rank correlation, residual chronologies of Fagus sylvatica could be separated into northern, central, and southern groups. This points to the existence of broad regions distributed along a latitudinal gradient, corresponding to large-scale climatic regimes over the Italian Peninsula.
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Cleaveland, Malcolm K. "Climatic Response of Densitometric Properties in Semiarid Site Tree Rings." Tree-Ring Society, 1986. http://hdl.handle.net/10150/261691.
Full textAbstract:
X-ray densitometry has proven useful in dendroclimatic research on relatively fast growing, complacent trees in mesic climates. The best dendrochronological materials, however, come from semiarid-site conifers that grow very slowly, have missing rings, are extremely sensitive to climate, and attain advanced ages. This study presents the first evaluation of X-ray densitometry of Douglas-fir, ponderosa pine, and pinyon from four semiarid sites in the eastern San Juan River Basin (northwestern New Mexico and southwestern Colorado). The relationship of climate with intra-annual tree-ring anatomy is anlyzed. Moving slit X-ray densitometry definest earlywood and latewood zones, yielding eight data types for each annual ring: total ring width, earlywood and latewood width, mean ring density, mean earlywood and latewood density, and minimum earlywood and maximum latewood density. response functions using regional averages of monthly mean temperature and total precipitation indicate that climate may strongly influence all eight types of data, depending on species and site conditions. Low moisture stress (cooler, wetter climate) increases total ring width, earlywood and latewood width, and ring, latewood, and maximum latewood density. High moisture stress increases earlywood and minimum earlywood density. The climate response of the density parameters differs from that reported for conifers in more mesic environments, although selected density parameters from a relatively mesic southwestern site are strongly related to climate. Site selection has nevertheless proven to be an important factor in getting the most climatically sensitive densitometric data. This study demonstrates that densitometry is feasible with conifers from semiarid sites. The intra-annual width and density data derived can increase the climate information available from these dry-site trees and should lead to improved seasonal and annual reconstructions of paleoclimate. Practical constraints imposed by current X-ray densitometric techniques may be removed with promising new procedures such as surface image analysis of cell anatomy.
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Shi, Chunming. "Paleoclimate information archived in tree-ring width and tree-ring stable isotopes on Tibetan Plateau." Versailles-St Quentin en Yvelines, 2011. http://www.theses.fr/2011VERS0023.
Full textAbstract:
Le plateau tibétain, avec une altitude moyenne de 4000m, est appelé le « troisième pôle de la Terre ». Il est l’objet d’une attention particulière dans les études qui portent sur le changement climatique global. D’une part, il constitue un obstacle physique à la circulation atmosphérique et, d’autre part, il agit comme un régulateur thermique qui réchauffe l’air sus-jacent en été et le refroidit en hiver. Le climat du plateau tibétain n’est pas une composante isolée du climat global mais bien une composante interactive avec les autres systèmes. En particulier, le plateau joue un rôle décisif dans la variabilité de la mousson asiatique qui affecte une aire géographique conséquente et densément peuplée. Soixante pourcent des eaux du Fleuve Jaune, dont dépendent plus de 100 millions de personnes et une industrie en pleine expansion, proviennent du plateau (Zhao et al. , 2008). Or, le débit de ce fleuve a diminué régulièrement depuis les années 1950 (Liu and Xia, 2004; Chang et al. , 2007). Il est crucial de comprendre comment les variations climatiques locales et globales affectent l’approvisionnement en eau de cette région appelée le « Château d’eau » de la Chine. Les enregistrements instrumentaux, qui ont généralement démarré dans la seconde moitié du 20ème siècle, sont toutefois trop courts pour appréhender la variabilité climatique. Le plateau tibétain offre une variété d’archives climatiques permettant d’étendre notre connaissance de la variabilité du climat au-delà des séries instrumentales. Le climat de haute altitude permet la formation de cernes d’arbres qui peuvent être parfaitement datés et offrent l’accès à une résolution saisonnière à annuelle. La largeur des cernes et la composition isotopique d’arbres anciens permettent, dans certaines conditions, de quantifier des paramètres clés du climat. Le potentiel de ces proxies pour reconstruire la variabilité des paramètres liés au cycle hydrologique (précipitation, humidité relative, couverture nuageuse, débit des rivières) reste à explorer. Cette thèse vise à répondre aux questions concernant la variabilité climatique sur le plateau au cours des derniers siècles. Les objectifs spécifiques sont : a) de déterminer les relations entre les variables climatiques du plateau et les paramètres des arbres (largeurs de cernes et composition isotopique de l’oxygène et du carbone de la cellulose) sur la période instrumentale, b) d’obtenir de longues séries de valeurs de largeurs de cernes et de composition isotopique de la cellulose et de les interpréter en termes climatiques, c) de reconstruire la variabilité climatique à partir de ces données et de leur confrontation à d’autres enregistrements de la variabilité climatique passée<br>The Tibetan plateau, 4000m high, is called the earth’s third pole. No other area in the world is a water repository of such size, serving as a lifeline for much of a continent and millions of people in countries downstream. The water supply in this head water region accounts for instance for more than 60% of the total runoff to the Yellow River (Zhao et al. , 2008). Climate evolution in Tibet would potentially have serious impacts. The current climate change could thus cause a rapid retreat of the glaciers with significant consequences on water resources in the region. However, the glacier water balance is influenced not only by local temperature variations, but also by precipitation ones. In southern Tibet, precipitation events exhibit a strong interannual-to-decadal variability directly related to the variability of Indian monsoon rainfall. To decipher the causes and the driving forces of water supply variability in the ‘water tower’ of China, it is therefore crucial to understand how it is affected by local and global climate changes. The climate and river flow in the source region of the Yellow River are documented through instrumental records starting in the 20th century. The Tibetan Plateau can offer a variety of climate archives but high-resolution proxy data, which are needed to document long-term climate change impacts, are still scarce in this area. The width and the isotopic composition of tree-ring have shown to be very valuable proxies of climate parameters. However, the potential of these proxies for reconstructing parameters linked to the hydrological cycle (precipitation, relative humidity, cloud cover, river flow) in this area still needs to be investigated. This thesis aims at characterizing climate variability in the Southern Tibetan Plateau over the last centuries. The main goals are: a) to determine the relations between some key climate parameters and tree-ring parameters (ring-width and cellulose 13C and 18O) over the instrumental time-period, b) to reconstruct and interpret climate variability in the South-Eastern Plateau over the last centuries from new tree-ring chronologies
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Ababneh, Linah Nabeeh. "Analysis of Radial Growth Patterns of Strip-Bark and Whole-Bark Bristlecone Pine Trees in the White Mountains of California: Implications in Paleoclimatology and Archaeology of the Great Basin." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/193510.
Full textAbstract:
Dendrochronology focuses on the relationship between a tree's growth and its environment and thus investigates interdisciplinary questions related to archaeology, climate, ecology, and global climate change. In this study, I examine the growth of two forms of bristlecone pine (Pinus longaeva): strip-bark and whole-bark trees from two subalpine adjacent sites: Patriarch Grove and Sheep Mountain in the White Mountains of California. Classical tree-ring width analysis is utilized to test a hypothesis related to a proposed effect of the strip-bark formation on trees' utilization of atmospheric carbon dioxide. This effect has grown to be controversial because of the dual effect of temperature and carbon dioxide on trees' growth. The proposed effect is hypothesized to have accelerated growth since 1850 that produced wider rings, and the relation of the latter topic to anthropogenic activities and climate change. An interdisciplinary approach is taken by answering a question that relates temperature inferences and precipitation reconstructions from the chronologies developed in the study and other chronologies to Native Americans subsistence settlements and alpine villages in the White Mountains. Strip-bark trees do exhibit an enhanced growth that varies between sites. Strip-bark trees grow faster than whole-bark trees, however, accelerated growth is also evident in whole-bark trees but to a lesser degree. No evidence can be provided on the cause of the accelerated growth from the methods used. In the archaeological study, 88% of the calibrated radiocarbon dates from the alpine villages of the White Mountains cluster around above average precipitation, while no straightforward relationship can be established with temperature variations. These results confirm that water is the essence of life in the desert.
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Moir, Andy. "The dendroclimatology of modern and neolithic scots pine (Pinus sylvestris l.) in the peatlands of northern Scotland." Thesis, Brunel University, 2008. http://bura.brunel.ac.uk/handle/2438/6028.
Full textAbstract:
For the first time in northern Scotland, Modern tree-ring chronologies for Scots pine growing on peat are compared against those growing on mineral substrates. Mean tree-ring growth of pine on active bogs/mires is found to be limited to 0.5 to 1 mm yr-1, compared to ≥1.5 mm yr-1 on adjacent mineral sites. Almost instant change of radial growth rates in response to changes in water levels highlights the potential use of pine in reconstructions of lake levels and water tables in bog and mire. Dendroclimatological analysis identifies January and February temperatures to often be more important than summer temperature. Positive correlation of ring-width and North Atlantic Oscillation (NAO) indices also occur in January and February. Lower winter temperatures, due to increased altitude and distance from the moderating effects of the ocean, may be important in limiting tree growth near its northern margin. Moving correlation functions identify a widespread reduction in the response of pine growing on both substrates from the 1920s. Nine subfossil pine site chronologies located beyond the species current northern limit are cross-matched to form a chronology called WRATH-9. This chronology is tentatively crossdated against Irish pine chronologies to provide the first picture of Neolithic Scots pines 200 year expansion from c. 3200 BC and subsequent 250 year retreat across northern Scotland at annual resolution. The mean orientation of maximum radial growth at eleven modern pine sites is found to coincide well with the W/SW prevailing wind, suggesting Scots pine may provide a good proxy indicator of wind. Six coeval Neolithic sites indicate a broadly consistent northerly prevailing wind. This provides tentative evidence for a change of prevailing wind that may be related to a southward incursion of the polar front in the eastern N. Atlantic. The potential of this exciting subfield of dendroclimatological analysis is called dendroaeology and is highlighted for further research.
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Tran, Tyler J., Jamis M. Bruening, Andrew G. Bunn, Matthew W. Salzer, and Stuart B. Weiss. "Cluster analysis and topoclimate modeling to examine bristlecone pine tree-ring growth signals in the Great Basin, USA." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/622956.
Full textAbstract:
Tree rings have long been used to make inferences about the environmental factors that influence tree growth. Great Basin bristlecone pine is a long-lived species and valuable dendroclimatic resource, but often with mixed growth signals; in many cases, not all trees at one location are limited by the same environmental variable. Past work has identified an elevational threshold below the upper treeline above which trees are limited by temperature, and below which trees tend to be moisture limited. This study identifies a similar threshold in terms of temperature instead of elevation through fine-scale topoclimatic modeling, which uses a suite of topographic and temperature-sensor data to predict temperatures across landscapes. We sampled trees near the upper limit of growth at four high-elevation locations in the Great Basin region, USA, and used cluster analysis to find dual-signal patterns in radial growth. We observed dual-signal patterns in ring widths at two of those sites, with the signals mimicking temperature and precipitation patterns. Trees in temperature-sensitive clusters grew in colder areas, while moisture-sensitive cluster trees grew in warmer areas. We found thresholds between temperature- and moisture-sensitivity ranging from 7.4 degrees C to 8 degrees C growing season mean temperature. Our findings allow for a better physiological understanding of bristlecone pine growth, and seek to improve the accuracy of climate reconstructions.
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Martin-Benito, Dario, Kevin Anchukaitis, Michael Evans, Río Miren del, Hans Beeckman, and Isabel Cañellas. "Effects of Drought on Xylem Anatomy and Water-Use Efficiency of Two Co-Occurring Pine Species." MDPI AG, 2017. http://hdl.handle.net/10150/625999.
Full textAbstract:
Exploring how drought influences growth, performance, and survival in different species is crucial to understanding the impacts of climate change on forest ecosystems. Here, we investigate the responses of two co-occurring pines (Pinus nigra and Pinus sylvestris) to interannual drought in east-central Spain by dendrochronological and wood anatomical features integrated with isotopic ratios of carbon (delta C-13) and oxygen (delta O-18) in tree rings. Our results showed that drought induces both species to allocate less carbon to build tracheid cell-walls but increases tracheid lumen diameters, particularly in the transition wood between early and latewood, potentially maximizing hydraulic conductivity but reducing resistance to embolism at a critical phase during the growing season. The thicker cell-wall-to-lumen ratio in P. nigra could imply that its xylem may be more resistant to bending stress and drought-induced cavitation than P. sylvestris. In contrast, the higher intrinsic water-use efficiency (iWUE) in P. sylvestris suggests that it relies more on a water-saving strategy. Our results suggest that narrower cell-walls and reduced growth under drought are not necessarily linked to increased iWUE. At our site P. nigra showed a higher growth plasticity, grew faster and was more competitive than P. sylvestris. In the long term, these sustained differences in iWUE and anatomical characters could affect forest species performance and composition, particularly under increased drought stress.
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Andreu, Hayles Laia. "Climate and Atmospheric CO2 Effects on Iberian Pine Forests assessed by Tree-Ring Chronologies and their potential for Climatic Reconstructions." Doctoral thesis, Universitat de Barcelona, 2007. http://hdl.handle.net/10803/1440.
Full textAbstract:
Two main purposes divided this Thesis into two parts, taking into account that the need of understanding current climatic fluctuations is still an important request of population living in the 21st century and the enormous wide range of responses observed to these changes depending on regions, ecosystems and/or species. The first main objective is to assess how climate and atmospheric CO2 concentration changes are affecting Iberian pine forests. The second aim is to extract the climatic signal registered by the studied stands with the aim of reconstructing past climate. Therefore, we will use the relationship between trees and climate in both directions: assessing the effects of climate on the forests, and afterwards, using these results to estimate climatic conditions before the existence of instrumental records. The methodology proposed is based on the study of width and delta-13C tree-ring chronologies established at different sites along the north and east of the Iberian Peninsula.<br/>Significant changes in tree-growth variability in a network of thirty-eight forests and in their climatic sensitivity (Chapter 1), as well as an increase in water use-efficiency of five selected stands (Chapter 2) in the Iberian Peninsula during the second half of the 20th century are unusual relative to the past. Growth pattern changes were related to recent warming and precipitation variability increase, while water-use efficiency trends were related to the rise of atmospheric CO2 concentration. <br/>Delta-13C values reflected drought stress signal during summer season better than ring width in tree-ring chronologies of five Spanish pine forests (Chapter 3). Summer precipitation reconstructions in Spain for the last 400 years were performed based on three width and Delta-13C tree-ring chronologies and significant links with large-scale atmospheric phenomenon as NAO and ENSO were established (Chapter 4). In addition to the well-known application of dendrochronological techniques to reconstruct past climate, our results highlight the enormous potential of combining different kind of tree-ring proxies in climatic research.<br>L'estudi realitzat es fonamenta en el fet que la necessitat d'entendre les fluctuacions del clima actual encara representa una important demanda de la població del segle XXI, així com en el gran ventall de respostes observades a aquests canvis en funció de regions, ecosistemes i/o espècies. La metodologia utilitzada es basa en l'estudi de cronologies de gruix i de Delta-13C dels anells dels arbres establertes en diferents localitats al llarg del nord i est de la Península Ibèrica. <br/>En primer lloc, aquesta tesi proporciona informació sobre la interacció entre el clima i els ecosistemes forestals, així com l'impacte que el canvi climàtic està tenint sobre ells. Canvis en el patró de creixement i en la sensibilitat climàtica d'una xarxa de 38 cronologies a la segona meitat del segle XX van ser relacionats amb el recent augment de les temperatures i de la variabilitat de les precipitacions. Per altra banda, un augment en l'eficiència de l'ús de l'aigua en cinc boscos seleccionats es va relacionar amb l'augment en la concentració del CO2 atmosfèric. En segon lloc, un cop demostrada i establerta la relació entre els boscos i el clima, es va extreure el senyal climàtic enregistrat en els arbres dels boscos estudiats amb la intenció de reconstruir el clima del passat anterior a l'existència de dades climàtiques instrumentals. Els valors de Delta-13C dels anells dels arbres van reflectir un senyal d'estrès hídric estival millor que el gruix d'aquests. Finalment, es van realitzar reconstruccions preliminars de la precipitació estival a España pels darrers 400 anys basades en cronologies d'anells dels arbres de gruix i de Delta-13C, establint relacions significatives entre elles, així com amb fenòmens atmosfèrics com la NAO i l'ENSO. Addicionalment, a la ben coneguda aplicació de les tècniques dendrocronològiques per a reconstruir el clima del passat, els nostres resultats destaquen l'enorme potencial de combinar diferents variables dels anells dels arbres en les investigacions climàtiques.<br>El estudio realizado parte del hecho que la necesidad de entender las fluctuaciones del clima actual todavía representa una importante demanda de la población del siglo XXI, así como del enorme rango de respuestas observadas a estos cambios dependiendo de regiones, ecosistemas y/o especies. La metodología utilizada se basa en el estudio de cronologías de grosor y de Delta-13C de los anillos de los árboles establecidas en diferentes localidades a lo largo del norte y este de la Península Ibérica. <br/>En primer lugar, esta tesis proporciona información sobre la interacción entre el clima y los ecosistemas forestales, así como el impacto que el cambio climático está teniendo sobre ellos. Cambios en el patrón de crecimiento y en la sensibilidad climática de una red de 38 cronologías en la segunda mitad del siglo XX fueran relacionados con el reciente aumento de las temperaturas y de la variabilidad de las precipitaciones. Por otro lado, un aumento en la eficiencia del uso del agua en cinco rodales seleccionados se relacionó con un aumento en la concentración del CO2 atmosférico. En segundo lugar, una vez demostrada y establecida la relación entre los bosques y el clima, se extrajo la señal climática registrada en los árboles de los bosques estudiados con la intención de reconstruir el clima del pasado anterior a la existencia de datos climáticos instrumentales. Los valores de Delta-13C de los anillos de los árboles reflejaron una señal de estrés hídrico estival mejor que el grosor de éstos. Finalmente, se realizaron reconstrucciones preliminares de la precipitación estival en España para los últimos 400 años basadas en cronologías de anillos de los árboles de grosor y de Delta-13C, estableciendo relaciones significativas entre ellas, así como con fenómenos atmosféricos como la NAO y el ENSO. Adicionalmente, a la bien conocida aplicación de las técnicas dendrocronológicas para reconstruir el clima del pasado, nuestros resultados destacan el enorme potencial de combinar diferentes variables de los anillos de los árboles en las investigaciones climáticas.
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Panyushkina, Irina P., Alexei A. Karpukhin та Asya V. Engovatova. "Moisture record of the Upper Volga catchment between AD 1430 and 1600 supported by a δ13C tree-ring chronology of archaeological pine timbers". ELSEVIER GMBH, URBAN & FISCHER VERLAG, 2016. http://hdl.handle.net/10150/622437.
Full textAbstract:
Investigations of interactions between climate change and humans suffer from the lack of climate proxies directly linked to historical or archaeological datasets that describe past environmental conditions at a particular location and time. We present a new set of pine tree-ring records (Pinus sylvestris L) developed from burial timbers excavated at the historical center of Yaroslavl city, Russia. A 171 year delta C-13 tree-ring chronology from AD 1430 to AD 1600 evidences mostly wet summers during the 15th century but exceptionally dry conditions of the 16th century at the Upper Volga catchment. According to the tree-ring record there were four major droughts (<-1.5 sigma) lasting from 9 to 26 years: 1501-1517, 1524-1533, 1542-1555 and 1570-1596, and major pluvials (>+1.5 sigma) lasting from 70 to 5 years: 1430-1500, 1518-1523, 1534-1541, and 1556-1564. We discuss a plausible contribution of these droughts to crop failures and city fires documented with historical chronicles for the Upper Volga catchment. The devastating drought regime of the 16th century corresponds to the loss of independence of the Yaroslavl principality to the Grand Duchy of Moscow and the formation of the centralized Russian State during the reign of Ivan the Terrible (1533-1584) underpinning the emergence of the Russian Empire. This study substantiates the value of archaeological timbers from the oldest Russian cities and inclusion of stable carbon isotope analysis for understanding hydroclimatic regimes across the mid latitudes of East European Plain, and their relationship to the history of Russia. (C) 2016 Elsevier GmbH. All rights reserved.
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Keen, Rachel M. "Using Tree-Ring Growth and Stable Isotopes to Explore Ponderosa Pine Ecophysiological Responses to Climate Variability and the 2012-2015 California Drought." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7511.
Full textAbstract:
Climate warming in recent decades has resulted in more frequent and severe drought events in the western United States. These changes are projected to continue, making it exceedingly important to understand how forests respond to severe drought stress, and how we can manage these forests to reduce mortality during future events. The 2012-2015 California drought is a recent example of a severe, multi-year drought that was coupled with an epidemic-scale outbreak of western pine beetle, killing nearly 90% of ponderosa pines in the central and southern Sierra Nevadas. In the first portion of this study, we compared pairs of surviving and dead ponderosa pines following this drought event to determine how the surviving trees were able to survive. We were also interested in how closely ponderosa pine tree-rings were recording ecosystem responses to this drought event. In the second portion of this study, we compared tree-ring growth rates and stable isotopes to data from an on-site flux tower to determine whether tree-rings were recording important information regarding ecosystem carbon and water fluxes during this severe drought event. Overall, we sought to better understand how the 2012- 2015 California drought event affected ponderosa pines to inform future management practices in forests of the western United States.
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Rebenack, Carrie E. "A Carbon and Oxygen Stable Isotope-Dendrochronology Study of Trees from South Florida: Implications for the Development of a High-Resolution Subtropical Paleoclimate Record." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/3009.
Full textAbstract:
The global paleoclimate archive is lacking in tropical dendrochronology studies as a result of limitations from inconsistent tree-ring production imposed by precipitation-driven seasonality. The slash pine, Pinus elliottii Engelm. var. densa, is the dominant canopy species of Big Pine Key (BPK) rocklands and has been shown to produce complicated, but distinct, ring structures; however, traditional dendrochronology studies have not established correlations between ring width measurements and major climate drivers controlling South Florida precipitation. My study utilized the carbon (δ13C) and oxygen (δ18O) isotope records in the α-cellulose component of tree-rings to extract information about the physiological responses of trees to climate and tropical cyclone activity. The δ13C measurements in the earlywood and latewood of four P. elliottii var. densa trees were used to build a chronology (1922-2005) and to distinguish annual growth from intra-annual density fluctuations (IADFs). Empirical orthogonal functions were used to determine individual response to precipitation, El Niño-Southern Oscillation (ENSO), and the Atlantic Multidecadal Oscillation (AMO). There is a distinct relationship between the δ13C values of cellulose and ENSO; however the nature (direct vs. inversely correlated) is temporally controlled by the prevailing phase of the AMO. The appearance of some IADFs coincide with the timing of El Niño winters occurring during the cool AMO phase, resulting in enriched δ13C values. The additional precipitation may encourage tree growth, but subsequent dry periods may slow growth and cause the tree to employ water-conservation strategies. Tree growth is influenced by the major climate drivers and the control they exert over the timing of precipitation; however, growth is ultimately controlled by the microenvironment surrounding individual trees. The δ18O and δ13C values of the latewood cellulose were compared to tropical cyclone activity occurring within a 100km radius of BPK. Tropical storms and depressions appeared as anomalously depleted values in the δ18O residual record, reflecting large amounts of tropical rain. The effects of hurricanes varied by storm; however, many of the major hurricanes (category 3-5) were preserved as an enrichments in the δ13C value of the following earlywood season. The application of stable isotope analyses greatly increases the breadth of paleoclimate information available from the trees.
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Ribas, Matamoros Montserrat. "Dendroecología de "Pinus halepensis" Mill. en Este de la Península Ibérica e Islas Baleares: Sensibilidad y grado de adaptación a las condiciones climáticas." Doctoral thesis, Universitat de Barcelona, 2006. http://hdl.handle.net/10803/83274.
Full textAbstract:
El objetivo principal que se plantea en el presente trabajo es determinar la plasticidad del crecimiento radial del pino carrasco (Pinus halepensis Mill.) frente al clima. Más concretamente, evaluar el grado de adecuación del crecimiento en grosor del tronco de las masas forestales de esta especie, a las distintas condiciones climáticas que se encuentran dentro de su área de distribución en España. Dicho propósito se aborda mediante el análisis de las series de crecimiento radial y su relación con el clima a distintas escalas temporales y espaciales.
Una primera perspectiva se basa en el seguimiento (realizado con resolución casi quincenal) del crecimiento radial del pino carrasco en una localidad situada dentro del Parc Natural del Garraf (Barcelona, Catalunya). La finalidad de este seguimiento es precisar el grado de ajuste de las tasas de crecimiento radial del pino carrasco a la variabilidad climática inter e intraanual. Dicho de otro modo, delimitar los períodos de actividad y reposo del crecimiento en grosor del tronco y definir qué factores climáticos controlan la formación de los anillos de crecimiento.
Los objetivos parciales que se plantean son:
(i) Establecer el patrón temporal del crecimiento radial (períodos de crecimiento y reposo).
(ii) Determinar el grado de ajuste del crecimiento radial de la especie a la variabilidad climática inter e intraanual a lo largo de los 10 años del seguimiento.
(iii) Identificar los factores que determinan las tasas de crecimiento en grosor del tronco, sus efectos en las sus características anatómicas del anillo de crecimiento y, la periodicidad con la que dichos anillos se forman.
Los resultados derivados de este seguimiento intensivo del crecimiento radial constituirán una base sólida para la interpretación de los resultados obtenidos en el estudio dendroclimático del pino carrasco en España, el cuál se basa en una red de cronologías del grosor de los anillos de crecimiento lo más extensa posible (temporal y espacialmente). Los objetivos en los que se desglosa este segundo propósito son los siguientes:
(i) Establecer una red de localidades representativa del área de distribución de la especie, de los bioclimas en los que habita y del tipo de masas forestales que encontramos en España; y describir detalladamente el clima de cada una de ellas, sus peculiaridades y sus tendencias temporales.
(ii) Caracterizar ecológicamente los bosques españoles de pino carrasco, mediante dos parámetros: Uno, la descripción de la estructura demográfica de edades y por tamaños y de las características actuales de las masas forestales (densidad, área basal, estructura espacial, etc.); y dos, la reconstrucción de su historia reciente (últimos 100 años) y obtención de su régimen de perturbaciones.
(iii) Establecer las relaciones entre el crecimiento (series del grosor de los anillos) y las condiciones climáticas locales, y de su variación a lo largo del este de la Península e Islas Baleares, resaltando el grado de adecuación del crecimiento radial del pino carrasco al clima en las distintas regiones bioclimáticas en las que se halla.
(iv) Analizar la variación espacial de los patrones de crecimiento radial de la especie en España y de su relación con el clima a escala regional; y valorar el grado en que dichas variaciones regionales pueden estar relacionadas con fenómenos de circulación atmosférica de escala global (teleconexiones climáticas).
(v) Contrastar la estabilidad temporal de las relaciones crecimiento-clima a escala local y regional.
La interpretación de los resultados obtenidos proporcionarán una visión global y precisa de la respuesta al cambio climático que pueden tener los bosques españoles de pino carrasco, la especie más importante en el paisaje español de baja altitud, no sólo por el área de territorio que ocupa sino por su importante función ecológica (ej. prevención de la erosión y perdida de suelo y recuperación del entorno natural después de perturbaciones, especialmente incendios).
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Lehečková, Eliška. "Citlivost letokruhových řad borovice lesní (Pinus sylvestris) ke klimatickým parametrům." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-325080.
Full textAbstract:
Presented master's thesis deals with the climate sensitivity of radial growth of Scots Pine (Pinus sylvestris) growing in the Protected Landscape Area Kokořínsko. The principal aim was to find out whether there are differences in the climate-growth response of pines growing on dry and mesic sites. To cope with that question tree ring cores were collected from stands on dry sandstones plateau and from stands near valley bottom with better water supply. Residual chronologies were developed and climatic factors limiting growth were identified using partial correlation analysis. The results show that pines on rocky sites respond positively to high precipitation during the vegetation season whereas trees on wetter sites react positively to high temperatures. In most study stands high February temperatures positively affect radial growth. Moving partial correlations analysis showed that the strongest responses to month climatic variables were stable over the studied period 1902 - 2009. Pointer years were determined and compared with precipitation and temperature anomalies in the corresponding pointer year, furthermore the effect of climate on number of trees with growth anomaly was studied using partial correlations analysis. Results of these analyses were in compliance with the previous findings. In...
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Ferguson, C. W., and D. A. Graybill. "Dendrochronology of Bristlecone Pine." 1985. http://hdl.handle.net/10150/246033.
Full textAbstract:
"A Final Technical Report Submitted 31 May 1985 on the National Science Foundation grant EAR-8018687 for the period 1 April 1981 to 31 October 1984 with the assistance of the Department of Energy contract no. DE-AC02-81EV10680 covering the period 1 May 1981 to 31 October 1982"<br>Since Edmund Schulman’s initial interest in 1953, the Laboratory of Tree-Ring Research has conducted dendrochronological studies of bristlecone pine (Pinus longaeva D. K. Bailey, sp. Nov.) in the White Mountains of east-central California where living trees reach ages in excess of 4,000 years. The focus of this report relates to the support by the Geology and Anthropology sections in the National Science Foundation under grant EAR-8018687 for the period 1 April 1981 to 31 October 1984 with the assistance of the Department of Energy contract no. DE-AC02-81EV10680 covering the period 1 May 1981 to 31 October 1982. A summary of this research was recently published in Radiocarbon (Ferguson and Graybill 1983). In most cases various facets of the work were related to projects sponsored by all agencies. Therefore the full range of activities during that period is described herein. The primary project goals were: To extend the bristlecone pine chronology from the White Mountains of California beyond 6700 B.C. and strengthen it by incorporating additional specimens. To develop bristlecone pine chronologies in new areas for applications in archaeology, isotopic studies, and other earth sciences. To furnish dendrochronologically dated wood to researchers engaged in the study of past variations in carbon isotopes and climate.
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Aldrich, Serena Rose. "Fire Regimes and Successional Dynamics of Pine and Oak Forests in the Central Appalachian Mountains." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9176.
Full textAbstract:
The role of fire in determining the structure and composition of many forested ecosystems is well documented (e.g. North American boreal forests; piñon-juniper woodlands of the western US). Fire is also believed to be important in temperate forests of eastern North America, but the processes acting here are less clear, particularly in xerophytic forests dominated by yellow pine (Pinus, subgenus Diploxylon Koehne) and oak (Quercus L.). In this study, I use dendroecological techniques to investigate fire history and vegetation dynamics of mixed pine-oak forests in the central Appalachian Mountains of Virginia. The study addresses three objectives: (1) develop a lengthy fire chronology to document fire history beginning in the late presettlement era and extending throughout the period of European settlement, industrialization and modern fire exclusion; (2) explore fire-climate relationships; and (3) investigate vegetation dynamics in relation to fire occurrence. The study was conducted on three study sites within the George Washington National Forest. I used fire-scarred cross-sections from yellow pine trees to document fire history. Fire-climate relationships were investigated for each study site individually and all sites combined using superposed epoch analysis (SEA). Fire-history information was coupled with dendroecological data on age structure to explore stand development in relation to fire occurrence. Results of fire history analysis reveal a long history of frequent fire with little temporal variation despite changes in land use history. Mean fire intervals (MFI) ranged from 3.7–17.4 years. The most important change in the fire regime was the initiation of fire suppression in the early twentieth century. Results of SEA show that periodic droughts may be important drivers of fire activity. Drought the year of fire was important at two of the three study sites and when all sites were combined. Results of age structure indicate that vegetation development was clearly influenced by fire. Frequent burning maintained populations of yellow pine throughout the period of study until fire suppression allowed fire-sensitive hardwood trees and shrubs to establish. It is clear from this study that continued fire suppression will likely result in fire-tolerant pines and oaks being replaced by more mesophytic trees and shrubs.
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Campelo, Filipe José Valente. "Climatic significance of tree-ring width and intra-annual wood features in Pinus pinea L. and Quercus ilex L." Doctoral thesis, 2008. http://hdl.handle.net/10316/9678.
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