Sample records for spruce forest thoughfall

  1. Long-Term Wet and Dry Deposition of Total and Methyl Mercury in the Remote Boreal Ecoregion of Canada

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Graydon, Jennifer A; Louis, Vincent; Hintelmann, Holger

    2008-11-01

    Although a positive relationship between atmospheric loadings of inorganic mercury (Hg(II)) to watersheds and concentrations of methyl mercury (MeHg) in fish has now been established, net wet and dry deposition of Hg(II) and MeHg to watersheds remains challenging to quantify. In this study, concentrations and loadings of total mercury (THg; all forms of Hg in a sample) and MeHg in open area wet deposition, throughfall, and litterfall were quantified at the remote Experimental Lakes Area in the boreal ecoregion, NW Ontario, Canada. Between 1992 and 2006, mean annual THg and MeHg loadings in the open were 36 17 and 0.5more » 0.2 mg ha 1, respectively. Throughfall THg and MeHg loadings were generally 2 4 times and 0.8 2 times higher, respectively, than loadings in the open. Loadings of both THg and MeHg were highest under an old growth spruce/fir canopy and lowest under a deciduous maple canopy, whereas loadings under young jack pine and wetland spruce/pine/alder canopies were intermediate. Litterfall generally represented the largest input of THg (86 105 mg ha 1) and MeHg (0.7 0.8 mg ha 1) to the landscape on an annual basis. Using the direct method of estimating dry deposition (thoughfall + litterfall open loadings), we calculated that annual dry deposition of THg and MeHg under forest canopies ranged from 105 to 201 mg ha 1, whereas dry deposition of MeHg ranged from 0.7 to 1.2 mg ha 1. Photoreduction and emission of wet-deposited Hg(II) from canopy foliage were accounted for, resulting in 3 5% (5 6 mg ha 1) higher annual estimates of dry deposition than via the direct method alone. Net THg and MeHg loadings to this remote landscape were lower than at any other previously studied forested site globally. This study shows that THg and MeHg loading can be extremely variable within a heterogeneous boreal landscape and that processes such as Hg photoreduction and emission from foliage should be considered when estimating dry deposition of Hg.« less

  2. [Community stability for spruce-fir forest at different succession stages in Changbai Mountains, Northeast China].

    PubMed

    Zhang, Meng-tao; Zhang, Qing; Kang, Xin-gang; Yang, Ying-jun; Xu, Guang; Zhang, Li-xin

    2015-06-01

    Based on the analysis of three forest communities (polar-birch secondary forest, spruce-fir mixed forest, spruce-fir near pristine forest) in Changbai Mountains, a total of 22 factors of 5 indices, including the population regeneration, soil fertility (soil moisture and soli nutrient), woodland productivity and species diversity that reflected community characteristics were used to evaluate the stability of forest community succession at different stages by calculating subordinate function values of a model based on fuzzy mathematics. The results that the indices of population regeneration, soli nutrient, woodland productivity and species diversity were the highest in the spruce-fir mixed forest, and the indices of soil moisture were the highest in the spruce-fir near-pristine forest. The stability of three forest communities was in order of natural spruce-fir mixed forest > spruce-fir near pristine forest > polar-birch secondary forest.

  3. Reproductive potential of balsam fir (Abies balsamea), white spruce (Picea glauca), and black spruce (P. mariana) at the ecotone between mixedwood and coniferous forests in the boreal zone of western Quebec.

    PubMed

    Messaoud, Yassine; Bergeron, Yves; Asselin, Hugo

    2007-05-01

    The reproductive potentials of balsam fir and white spruce (co-dominants in mixedwood forests) and black spruce (dominant in coniferous forests) were studied to explain the location of the ecotone between the two forest types in the boreal zone of Quebec. Four sites were selected along a latitudinal gradient crossing the ecotone. Cone crop, number of seeds per cone, percentage filled seeds, and percentage germination were measured for each species. Balsam fir and white spruce cone crops were significantly lower in the coniferous than in the mixedwood forest, while black spruce had greater crop constancy and regularity between both forest types. Mast years were more frequent for black spruce than for balsam fir in both forest types (mast year data not available for white spruce). The number of seeds per cone was more related to cone size than to forest type for all species. Black spruce produced more filled seeds in the coniferous forest than balsam fir or white spruce. The sum of growing degree-days and the maximum temperature of the warmest month (both for the year prior to cone production) significantly affected balsam fir cone production. The climate-related northward decrease in reproductive potential of balsam fir and white spruce could partly explain the position of the northern limit of the mixedwood forest. This could change drastically, however, as the ongoing climate warming might cancel this competitive advantage of black spruce.

  4. Densities of breeding birds and changes in vegetation in an alaskan boreal forest following a massive disturbance by spruce beetles

    USGS Publications Warehouse

    Matsuoka, S.M.; Handel, C.M.; Ruthrauff, D.R.

    2001-01-01

    We examined bird and plant communities among forest stands with different levels of spruce mortality following a large outbreak of spruce beetles (Dendroctonus rufipennis (Kirby)) in the Copper River Basin, Alaska. Spruce beetles avoided stands with black spruce (Picea mariana) and selectively killed larger diameter white spruce (Picea glauca), thereby altering forest structure and increasing the dominance of black spruce in the region. Alders (Alnus sp.) and crowberry (Empetrum nigrum) were more abundant in areas with heavy spruce mortality, possibly a response to the death of overstory spruce. Grasses and herbaceous plants did not proliferate as has been recorded following outbreaks in more coastal Alaskan forests. Two species closely tied to coniferous habitats, the tree-nesting Ruby-crowned Kinglet (Regulus calendula) and the red squirrel (Tamiasciurus hudsonicus), a major nest predator, were less abundant in forest stands with high spruce mortality than in low-mortality stands. Understory-nesting birds as a group were more abundant in forest stands with high levels of spruce mortality, although the response of individual bird species to tree mortality was variable. Birds breeding in stands with high spruce mortality likely benefited reproductively from lower squirrel densities and a greater abundance of shrubs to conceal nests from predators.

  5. Relationships between forest structure, composition, site, and spruce beetle occurrence in the Intermountain West

    Treesearch

    R. Justin DeRose; James N. Long; John D. Shaw

    2009-01-01

    Engelmann spruce forests are structurally and compositionally diverse, occur across a wide range of physiographic conditions, and are the result of varying disturbance histories such as fire, wind and spruce beetle. The spruce beetle is a natural disturbance agent of spruce forests and has population levels that fluctuate from endemic to epidemic. Conceptually,...

  6. Lessons from native spruce forests in Alaska: managing Sitka spruce plantations worldwide to benefit biodiversity and ecosystem services

    Treesearch

    Robert L. Deal; Paul Hennon; Richard O' Hanlon; David D' Amore

    2014-01-01

    There is increasing interest worldwide in managing forests to maintain or improve biodiversity, enhance ecosystem services and assure long-term sustainability of forest resources. An important goal of forest management is to increase stand diversity, provide wildlife habitat and improve forest species diversity. We synthesize results from natural spruce forests in...

  7. Spruce budworm returns to Northeast

    Treesearch

    Lloyd Irland; William H. McWilliams

    2014-01-01

    Thinking of the Northern Forest brings to mind spruce/fir (S/F) forests, cool climates, and high elevations: not to mention fishing and canoe trips: however, spruce and fir are also very important to the northern timber economy and rural development. Considering new concerns over the spruce budworm, an update on the status of this critically important forest resource...

  8. Proceedings, forest defoliator—host interactions: A comparison between gypsy moth and spruce budworms

    Treesearch

    Robert L. Talerico; Michael Montgomery

    1983-01-01

    The Canada/U.S. Spruce Budworms Program in cooperation with the Center for Biological Control of Northeastern Forest Insects and Diseases of the Northeastern Forest Experiment Station co-sponsored this Forest Defoliator-Host Interaction Workshop.This invitational workshop was limited to investigators of the spruce bud worms and gypsy moth in the Forest Service,...

  9. Nesting ecology of boreal forest birds following a massive outbreak of spruce beetles

    USGS Publications Warehouse

    Matsuoka, S.M.; Handel, C.M.

    2007-01-01

    We studied breeding dark-eyed juncos (Junco hyemalis), yellow-rumped warblers (Dendroica coronata), and spruce-nesting birds from 1997 to 1998 among forests with different levels of spruce (Picea spp.) mortality following an outbreak of spruce beetles (Dendroctonus rufipennis) in Alaska, USA. We identified species using live and beetle-killed spruce for nest sites and monitored nests to determine how the outbreak influenced avian habitat selection and reproduction. We tested predictions that 1) nesting success of ground-nesting juncos would increase with spruce mortality due to proliferation of understory vegetation available to conceal nests from predators, 2) nesting success of canopy-nesting warblers would decrease with spruce mortality due to fewer live spruce in which to conceal nests, and 3) both species would alter nest-site selection in response to disturbance. Juncos did not benefit from changes in understory vegetation; nesting success in highly disturbed stands (46%) was comparable to that in undisturbed habitats throughout their range. In stands with low spruce mortality, nesting success of juncos was low (5%) and corresponded with high densities of red squirrels (Tamiasciurus hudsonicus). Yellow-rumped warblers nested exclusively in spruce, but success did not vary with spruce mortality. As disturbance increased, nesting warblers switched from selecting forest patches with high densities of live white spruce (Picea glauca) to patches with beetle-killed spruce. Warblers also placed nests in large-diameter live or beetle-killed spruce, depending on which was more abundant in the stand, with no differences in nesting success. Five of the 12 other species of spruce-nesting birds also used beetle-killed spruce as nest sites. Because beetle-killed spruce can remain standing for >50 years, even highly disturbed stands provide an important breeding resource for boreal forest birds. We recommend that boreal forest managers preserve uncut blocks of infested forest within managed forest landscapes and practice partial harvest of beetle-killed spruce rather than commercial clear-cutting of infested stands in order to sustain breeding bird populations until natural reforestation occurs. Because breeding densities do not always reflect fitness, assessing impacts of a massive natural disturbance should include measuring impacts of changes in vegetation on both reproductive success and predator–prey dynamics.

  10. Changes in conifer and deciduous forest foliar and forest floor chemistry and basal area tree growth across a nitrogen (N) deposition gradient in the northeastern US

    Treesearch

    Johnny L. Boggs; Steven G. McNulty; Linda H. Pardo

    2007-01-01

    We evaluated foliar and forest floor chemistry across a gradient of N deposition in the Northeast at 11 red spruce (Picea rubens Sarg.) sites in 1987/1988 and foliar and forest floor chemistry and basal area growth at six paired spruce and deciduous sites in 1999. The six red spruce plots were a subset of the original 1987/1988 spruce sites. In 1999...

  11. Characterizing forest vegetation of the Tanana Valley: what can forest inventory and analysis deliver?

    Treesearch

    Bethany Schulz

    2015-01-01

    Vegetation profile data were collected as part of a forest inventory project in the Tanana Valley in interior Alaska, providing a means of characterizing the forest vegetation. The black spruce forest type was most common, followed by Alaska paper birch, and white spruce, quaking aspen, and balsam poplar. For individual tree species, black spruce was recorded on 68...

  12. Effects of forest management legacies on spruce budworm (Choristoneura fumiferana) outbreaks

    Treesearch

    Louis-Etienne Robert; Daniel Kneeshaw; Brian R. Sturtevant

    2012-01-01

    The "silvicultural hypothesis" of spruce budworm (Choristoneura fumiferana Clem.) dynamics postulates that increasing severity of spruce budworm outbreaks over the last century resulted from forest conditions created by past management activities. Yet, definitive tests of the hypothesis remain elusive. We examined spruce budworm outbreak...

  13. Effect of increasing temperatures on the distribution of spruce beetle in Engelmann spruce forests of the Interior West, USA

    Treesearch

    R. Justin DeRose; Barbara J. Bentz; James N. Long; John D. Shaw

    2013-01-01

    The spruce beetle (Dendoctronus rufipennis) is a pervasive bark beetle indigenous to spruce (Picea spp.) forests of North America. In the last two decades outbreaks of spruce beetle have increased in severity and extent. Increasing temperatures have been implicated as they directly control beetle populations, potentially inciting endemic populations to build to...

  14. The Status of White Spruce Plantations on Lake States National Forests

    Treesearch

    Glen W. Erickson; H. Michael Rauscher

    1985-01-01

    Summarizes information about white spruce plantations as of 1982. Based on average site index, the Superior National Forest in Minnesota and the Hiawatha and Huron-Manistee in Michigan contain climate-soil-seed source complexes that are, on the average, less productive for white spruce than on the other National Forests

  15. Spectral evidence of early-stage spruce beetle infestation in Engelmann spruce

    Treesearch

    Adrianna C. Foster; Jonathan A. Walter; Herman H. Shugart; Jason Sibold; Jose Negron

    2017-01-01

    Spruce beetle (Dendroctonus rufipennis (Kirby)) outbreaks cause widespread mortality of Engelmann spruce (Picea engelmannii (Parry ex Engelm)) within the subalpine forests of the western United States. Early detection of infestations could allow forest managers to mitigate outbreaks or anticipate a response to tree mortality and the potential effects on ecosystem...

  16. Natural development and regeneration of a Central European montane spruce forest

    Treesearch

    Miroslav Svoboda; Shawn Fraver; Pavel Janda; Radek Bače; Jitka Zenáhlíková

    2010-01-01

    Montane Norway spruce forests of Central Europe have a very long tradition of use for timber production; however, recently there has been increasing concern for their role in maintaining biological diversity. This concern, coupled with recent severe windstorms that led to wide-spread bark beetle outbreaks, has brought the management of montane spruce forests to the...

  17. Integrated permanent plot and aerial monitoring for the spruce budworm decision support system

    Treesearch

    David A. MacLean

    2000-01-01

    Spruce budworm (Choristoneura fumiferana Clem.) outbreaks cause severe mortality and growth loss of spruce and fir forest over ranch of eastern North America. The Spruce Budworm Decision Support System (DSS) links prediction and interpretation models to the ARC/1NFO GIS, under an ArcView graphical user interface. It helps forest managers predict...

  18. Pulpwood, pesticides, and people. Controlling spruce budworm in northeastern North America

    NASA Astrophysics Data System (ADS)

    Irland, Lloyd C.

    1980-09-01

    The eastern spruce budworm is a major forest pest over the continental range of the spruce-fir forest ecosystem and its southern ecotonal fringes in Canada and the northeastern United States. The current budworm outbreak illustrates the difficulty of arriving at economically sound and publicly acceptable forest pest control policies. Policies ranging from no use of chemical control to annual widespread crop protection have been adopted. There is no single all-around “best” policy for spruce budworm control. Chemical spray programs have demonstrably slowed the normal progress of mortality due to budworm, but have not eradicated the pest. Where industry remains heavily dependent on a fully utilized spruce-fir forest, no easy, low-cost solutions to the budworm problem exist. Reliance on spraying will have to be reduced and plans made to utilize higher levels of tree mortality and to manage the forest for lower future vulnerability.

  19. Changes in downed and dead woody material following a spruce beetle outbreak on the Kenai Peninsula, Alaska.

    Treesearch

    Bethany Schulz

    2003-01-01

    The forests of the Kenai Peninsula, Alaska, underwent a major spruce beetle(Dendroctonus rufipennis (Kirby)) outbreak in the 1990s. A repeated inventory of forest resources was designed to assess the effects of the resulting widespread mortality of spruce trees, the dominant component of the Kenai forests. Downed woody materials, fuel heights, and...

  20. A key for predicting postfire successional trajectories in black spruce stands of interior Alaska.

    Treesearch

    Jill F. Johnstone; Teresa N. Hollingsworth; F. Stuart Chapin

    2008-01-01

    Black spruce (Picea mariana (Mill) B.S.P) is the dominant forest cover type in interior Alaska and is prone to frequent, stand-replacing wildfires. Through impacts on tree recruitment, the degree of fire consumption of soil organic layers can act as an important determinant of whether black spruce forests regenerate to a forest composition similar...

  1. Using maximum entropy modeling to identify and prioritize red spruce forest habitat in West Virginia

    Treesearch

    Nathan R. Beane; James S. Rentch; Thomas M. Schuler

    2013-01-01

    Red spruce forests in West Virginia are found in island-like distributions at high elevations and provide essential habitat for the endangered Cheat Mountain salamander and the recently delisted Virginia northern flying squirrel. Therefore, it is important to identify restoration priorities of red spruce forests. Maximum entropy modeling was used to identify areas of...

  2. Performance of the Forest Vegetation Simulator in managed white spruce plantations influenced by eastern spruce budworm in northern Minnesota

    Treesearch

    Matthew B. Russell; Anthony W. D' Amato; Michael A. Albers; Christopher W. Woodall; Klaus J. Puettmann; Michael R. Saunders; Curtis L. VanderSchaaf

    2015-01-01

    Silvicultural strategies such as thinning may minimize productivity losses from a variety of forest disturbances, including forest insects. This study analyzed the 10-year postthinning response of stands and individual trees in thinned white spruce (Picea glauca [Moench] Voss) plantations in northern Minnesota, USA, with light to moderate defoliation...

  3. Mortality patterns following spruce budworm infestation in unprotected spruce-fir forests in Maine

    Treesearch

    Dale S. Solomon; Lianjun Zhang; Thomas B. Brann; David S. Larrick

    2003-01-01

    Cumulative and annual mortality of red spruce (Picea rubens Sarg.) and balsam fir [Abies balsamea (L) Mill.] were examined over a 10 yr period to follow the mortality patterns in unprotected spruce-fir forests in northern Maine. Different mortality patterns were determined based on stand composition classes and merchantability classes. In general, balsam fir was more...

  4. Stand and landscape level effects of a major outbreak of spruce beetles on forest vegetation in the Copper River Basin, Alaska

    USGS Publications Warehouse

    Allen, J.L.; Wesser, S.; Markon, C.J.; Winterberger, K.C.

    2006-01-01

    From 1989 to 2003, a widespread outbreak of spruce beetles (Dendroctonus rufipennis) in the Copper River Basin, Alaska, infested over 275,000 ha of forests in the region. During 1997 and 1998, we measured forest vegetation structure and composition on one hundred and thirty-six 20-m ?? 20-m plots to assess both the immediate stand and landscape level effects of the spruce beetle infestation. A photo-interpreted vegetation and infestation map was produced using color-infrared aerial photography at a scale of 1:40,000. We used linear regression to quantify the effects of the outbreak on forest structure and composition. White spruce (Picea glauca) canopy cover and basal area of medium-to-large trees [???15 cm diameter-at-breast height (1.3 m, dbh)] were reduced linearly as the number of trees attacked by spruce beetles increased. Black spruce (Picea mariana) and small diameter white spruce (<15 cm dbh) were infrequently attacked and killed by spruce beetles. This selective attack of mature white spruce reduced structural complexity of stands to earlier stages of succession and caused mixed tree species stands to lose their white spruce and become more homogeneous in overstory composition. Using the resulting regressions, we developed a transition matrix to describe changes in vegetation types under varying levels of spruce beetle infestations, and applied the model to the vegetation map. Prior to the outbreak, our study area was composed primarily of stands of mixed white and black spruce (29% of area) and pure white spruce (25%). However, the selective attack on white spruce caused many of these stands to transition to black spruce dominated stands (73% increase in area) or shrublands (26% increase in area). The post-infestation landscape was thereby composed of more even distributions of shrubland and white, black, and mixed spruce communities (17-22% of study area). Changes in the cover and composition of understory vegetation were less evident in this study. However, stands with the highest mortality due to spruce beetles had the lowest densities of white spruce seedlings suggesting a longer forest regeneration time without an increase in seedling germination, growth, or survival. ?? 2006 Elsevier B.V. All rights reserved.

  5. A comparison of the status of spruce in high-elevation forests on public and private land in the southern and central Appalachian Mountains

    Treesearch

    Randall S. Morin; Richard H. Widmann

    2010-01-01

    Red spruce (Picea rubens Sarg.) is the most important component of the high-elevation forest ecosystems of the southern and central Appalachian Mountains. These communities are characterized by mixed hardwood/coniferous forests often with overstory dominance by red spruce. Due to their restricted geographic and elevation ranges, all community types...

  6. Release of Suppressed Red Spruce Using Canopy Gap Creation--Ecological Restoration in the Central Appalachians

    Treesearch

    J.S. Rentch; W.M. Ford; Thomas Schuler; Jeff Palmer; C.A. Diggins

    2016-01-01

    Red spruce (Picea rubens) and red spruce-northern hardwood mixed stands once covered as much as 300,000 ha in the Central Appalachians, but now comprise no more than 21,000 ha. Recently, interest in restoration of this forest type has increased because red spruce forests provide habitat for a number of rare animal species. Our study reports the...

  7. Small-forest management in the spruce-fir region

    Treesearch

    A. C. Hart

    1953-01-01

    Small forest properties occupy about 3.4 million acres, or 25 percent of the total forest land, in the spruce-fir region of Maine and New Hampshire. Careful management of these small forest properties is important to the region and to the owners.

  8. South-central Alaska forests: inventory highlights.

    Treesearch

    Sally Campbell; Willem W.S. van Hees; Bert. Mead

    2005-01-01

    This publication presents highlights of a recent south-central Alaska inventory conducted by the Pacific Northwest Research Station Forest Inventory and Analysis Program (USDA Forest Service). South-central Alaska has about 18.5 million acres, of which one-fifth (4 million acres) is forested. Species diversity is greatest in closed and open Sitka spruce forests, spruce...

  9. Spruce reproduction dynamics on Alaska's Kenai Peninsula, 1987-2000.

    Treesearch

    Willem W.S. van Hees

    2005-01-01

    During the past 30 years, spruce forests of Alaska’s Kenai Peninsula have undergone dramatic changes resulting from widespread spruce bark beetle(Dendroctonus rufipennis (Kirby)) infestation. In 1987 and again in 2000, the Pacific Northwest Research Station's Forest Inventory and Analysis Program conducted initial and remeasurement inventories...

  10. Effect of species composition on carbon and nitrogen stocks in forest floor and mineral soil in Norway spruce and European beech mixed forests

    NASA Astrophysics Data System (ADS)

    Andivia, Enrique; Rolo, Víctor; Jonard, Mathieu; Formánek, Pavel; Ponette, Quentin

    2015-04-01

    Management of existing forests has been identified as the main strategy to enhance carbon sequestration and to mitigate the impact of climate change on forest ecosystems. In this direction, the conversion of Norway spruce monospecific stands into mixed stands by intermingling individuals of European beech is an ongoing trend in adaptive forest management strategies, especially in Central Europe. However, studies assessing the effect of changes in tree species composition on soil organic carbon (SOC) and nitrogen stocks are still scarce and there is a lack of scientific evidence supporting tree species selection as a feasible management option to mitigate the effects of predicted future climatic scenarios. We compared C and N stocks in the forest floor (litter and humus) and the top 10 cm of mineral soil in two monospecific stands of Norway spruce and European beech and in a mixed stand of both species. The effect of tree species composition on the C and N stocks and its spatial distribution was evaluated based on litterfall, root production, elevation and canopy opening, and by using a combination of modelling and geostatistical techniques. C stock was highest in the Norway spruce and the mixed stands, while N stock was highest in the mixed stand and lowest under European beech, with intermediate values in the Norway spruce stand. Each forest type showed differences in forest floor properties, suggesting that species composition is an important factor governing forest floor characteristics, including C and N stocks. The distribution of C and N stocks between forest soil layers was different for each forest type. C and N stocks were highest in the hummus layer under Norway spruce, whereas both stocks were lowest in the European beech stand. On the other hand, the mixed stand showed the highest C and N accumulation in the uppermost mineral soil layer, while the monospecific stands showed similar values. Litterfall was the main contribution to C and N stocks of the humus layer in monospecific stands. Forest floor stocks were also influenced by microelevation and canopy opening in the European beech stand and by microelevation in the Norway spruce stand. Root turnover and Norway spruce litterfall proportion directly increased C stocks in the mineral soil of the mixed stand. Additionally, N stock in the forest floor of the mixed stand was positively correlated with the Norway spruce litterfall proportion. Spatial analyses further confirmed that species composition was the main source of spatial variability of SOC stock in mixed stands. These results suggest that the admixture of individuals of European beech and Norway spruce may lead to a translocation of SOC from the forest floor to the better protected mineral soil layer, which might be beneficial for long term SOC sequestration.

  11. Belowground effects of enhanced tropospheric ozone and drought in a beech/spruce forest (Fagus sylvatica L./Picea abies [L.] Karst).

    PubMed

    Nikolova, Petia S; Andersen, Christian P; Blaschke, Helmut; Matyssek, Rainer; Häberle, Karl-Heinz

    2010-04-01

    The effects of experimentally elevated O(3) on soil respiration rates, standing fine-root biomass, fine-root production and delta(13)C signature of newly produced fine roots were investigated in an adult European beech/Norway spruce forest in Germany during two subsequent years with contrasting rainfall patterns. During humid 2002, soil respiration rate was enhanced under elevated O(3) under beech and spruce, and was related to O(3)-stimulated fine-root production only in beech. During dry 2003, the stimulating effect of O(3) on soil respiration rate vanished under spruce, which was correlated with decreased fine-root production in spruce under drought, irrespective of the O(3) regime. delta(13)C signature of newly formed fine-roots was consistent with the differing g(s) of beech and spruce, and indicated stomatal limitation by O(3) in beech and by drought in spruce. Our study showed that drought can override the stimulating O(3) effects on fine-root dynamics and soil respiration in mature beech and spruce forests. 2009 Elsevier Ltd. All rights reserved.

  12. Migration and bioavailability of (137)Cs in forest soil of southern Germany.

    PubMed

    Konopleva, I; Klemt, E; Konoplev, A; Zibold, G

    2009-04-01

    To give a quantitative description of the radiocaesium soil-plant transfer for fern (Dryopteris carthusiana) and blackberry (Rubus fruticosus), physical and chemical properties of soils in spruce and mixed forest stands were investigated. Of special interest was the selective sorption of radiocaesium, which was determined by measuring the Radiocaesium Interception Potential (RIP). Forest soil and plants were taken at 10 locations of the Altdorfer Wald (5 sites in spruce forest and 5 sites in mixed forest). It was found that the bioavailability of radiocaesium in spruce forest was on average seven times higher than in mixed forest. It was shown that important factors determining the bioavailability of radiocaesium in forest soil were its exchangeability and the radiocaesium interception potential (RIP) of the soil. Low potassium concentration in soil solution of forest soils favors radiocaesium soil-plant transfer. Ammonium in forest soils plays an even more important role than potassium as a mobilizer of radiocaesium. The availability factor - a function of RIP, exchangeability and cationic composition of soil solution - characterized reliably the soil-plant transfer in both spruce and mixed forest. For highly organic soils in coniferous forest, radiocaesium sorption at regular exchange sites should be taken into account when its bioavailability is considered.

  13. Bareroot nursery production and practices for white spruce: a literature review.

    Treesearch

    A.A. Alm; V.M. Vaughn; H.M. Rauscher

    1991-01-01

    This summary of white spruce literature covers seed collection and treatment, nursery cultural practices, seedling growth patterns and measurements of seedling quality. It includes information relevant to bareroot white spruce but does not cover containerized seedlings. It is intended for forest land managers, researchers and bareroot forest nursery managers.

  14. Reconstruction of stand dynamics over the last 2500 years from spruce remains in a treeline peatland

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arseneault, D.; Payette, S.

    1995-06-01

    Stem remains of black spruce Picea mariana (Mill. BSP.) buried in a permafrost treeless peatland were used for the reconstruction of the long-term forest dynamics at treeline in northeastern Canada. Because most spruce remains were well preserved, forest development was assessed from stem morphology (growth form) and tree ring patterns. The peatland border was colonized by a spruce forest from at least 500 BC (2500 BP) to 1568 AD. Most spruce individuals showed an erect, monopodial bole with only minor stem damage at the snow-air interface. The forest successfully regenerated after two fire events around 350 BC and 10 AD.more » The number of damaged stems at the snow-air interface increased after another fire around 700 AD, although faster ring growth occurred between 860 and 1000 AD (Medieval period). The forest shifted to an open krummholz after the last fire in 1568 AD because of reduced postfire regeneration and site opening. Reforestation of the site would necessitate sustained warmer conditions than those presently prevailing there.« less

  15. Effects of fire on the thermal stability of permafrost in lowland and upland black spruce forests of interior Alaska in a changing climate

    USGS Publications Warehouse

    Jafarov, Elchin E.; Romanovsky, Vladimir E.; Genet, Helene; McGuire, Anthony David; Marchenko, Sergey S.

    2013-01-01

    Fire is an important factor controlling the composition and thickness of the organic layer in the black spruce forest ecosystems of interior Alaska. Fire that burns the organic layer can trigger dramatic changes in the underlying permafrost, leading to accelerated ground thawing within a relatively short time. In this study, we addressed the following questions. (1) Which factors determine post-fire ground temperature dynamics in lowland and upland black spruce forests? (2) What levels of burn severity will cause irreversible permafrost degradation in these ecosystems? We evaluated these questions in a transient modeling–sensitivity analysis framework to assess the sensitivity of permafrost to climate, burn severity, soil organic layer thickness, and soil moisture content in lowland (with thick organic layers, ~80 cm) and upland (with thin organic layers, ~30 cm) black spruce ecosystems. The results indicate that climate warming accompanied by fire disturbance could significantly accelerate permafrost degradation. In upland black spruce forest, permafrost could completely degrade in an 18 m soil column within 120 years of a severe fire in an unchanging climate. In contrast, in a lowland black spruce forest, permafrost is more resilient to disturbance and can persist under a combination of moderate burn severity and climate warming.

  16. Mapping the current and potential distribution of red spruce in Virginia: implications for the restoration of degraded high elevation habitat

    Treesearch

    Heather Griscom; Helmut Kraenzle; Zachary. Bortolot

    2010-01-01

    The objective of our project is to create a habitat suitability model to predict potential and future red spruce forest distributions. This model will be used to better understand the influence of climate change on red spruce distribution and to help guide forest restoration efforts.

  17. Altitudinal gradients of bryophyte diversity and community assemblage in southern Appalachian spruce-fir forests

    Treesearch

    Sarah E. Stehn; Christopher R. Webster; Janice M. Glime; Michael A. Jenkins

    2010-01-01

    Ground-layer plant communities in spruce-fir forests of the southern Appalachians have likely undergone significant change since the widespread death of canopy Fraser fir (Abies fraseri) caused by the exotic balsam woolly adelgid (Adelges piceae). Bryophytes comprise an important part of the ground-layer flora in the spruce-fir...

  18. The influence of spruce on acidity and nutrient content in soils of Northern Taiga dwarf shrub-green moss spruce forests

    NASA Astrophysics Data System (ADS)

    Orlova, M. A.; Lukina, N. V.; Smirnov, V. E.; Artemkina, N. A.

    2016-11-01

    Presently, among the works considering the influence of forest trees on soil properties, the idea that spruce ( Picea abies) promotes the acidification of soils predominates. The aim of this work is to assess the effects of spruce trees of different ages and Kraft classes on the acidity and content of available nutrient compounds in the soils under boreal dwarf shrub-green moss spruce forests by the example of forest soils in the Kola Peninsula. The soils are typical iron-illuvial podzols (Albic Rustic Podzols (Arenic)). Three probable ways of developing soils under spruce forests with the moss-dwarf shrub ground cover are considered. The soils under windfall-soil complexes of flat mesodepressions present the initial status. The acidity of organic soil horizons from the initial stage of mesodepression overgrowth to the formation of adult trees changed nonlinearly: the soil acidity reached its maximum under the 30-40-year-old trees and decreased under the trees older than 100 years. The contents of nitrogen and available nutrients increased. The acidity of the mineral soil horizons under the trees at the ages of 110-135 and 190-220 years was comparable, but higher than that under the 30-40-year-old trees. The differences in the strength and trends of the trees' effect on the soils are explained by the age of spruce trees and their belonging to different Kraft classes.

  19. Space sequestration below ground in old-growth spruce-beech forests-signs for facilitation?

    PubMed

    Bolte, Andreas; Kampf, Friederike; Hilbrig, Lutz

    2013-01-01

    Scientists are currently debating the effects of mixing tree species for the complementary resource acquisition in forest ecosystems. In four unmanaged old-growth spruce-beech forests in strict nature reserves in southern Sweden and northern Germany we assessed forest structure and fine rooting profiles and traits (≤2 mm) by fine root sampling and the analysis of fine root morphology and biomass. These studies were conducted in selected tree groups with four different interspecific competition perspectives: (1) spruce as a central tree, (2) spruce as competitor, (3) beech as a central tree, and (4) beech as competitor. Mean values of life fine root attributes like biomass (FRB), length (FRL), and root area index (RAI) were significantly lower for spruce than for beech in mixed stands. Vertical profiles of fine root attributes adjusted to one unit of basal area (BA) exhibited partial root system stratification when central beech is growing with spruce competitors. In this constellation, beech was able to raise its specific root length (SRL) and therefore soil exploration efficiency in the subsoil, while increasing root biomass partitioning into deeper soil layers. According to relative values of fine root attributes (rFRA), asymmetric below-ground competition was observed favoring beech over spruce, in particular when central beech trees are admixed with spruce competitors. We conclude that beech fine rooting is facilitated in the presence of spruce by lowering competitive pressure compared to intraspecific competition whereas the competitive pressure for spruce is increased by beech admixture. Our findings underline the need of spatially differentiated approaches to assess interspecific competition below ground. Single-tree approaches and simulations of below-ground competition are required to focus rather on microsites populated by tree specimens as the basic spatial study area.

  20. Using silviculture to influence carbon sequestration in southern Appalachian spruce-fir forests

    Treesearch

    Patrick T. Moore; R. Justin DeRose; James N. Long; Helga van Miegroet

    2012-01-01

    Enhancement of forest growth through silvicultural modification of stand density is one strategy for increasing carbon (C) sequestration. Using the Fire and Fuels Extension of the Forest Vegetation Simulator, the effects of even-aged, uneven-aged and no-action management scenarios on C sequestration in a southern Appalachian red spruce-Fraser fir forest were modeled....

  1. Microbial communities in the litter of middle taiga bilberry-spruce forests

    NASA Astrophysics Data System (ADS)

    Sizonenko, T. A.; Zagirova, S. V.; Khabibullina, F. M.

    2010-10-01

    The structure of the microbial communities in the litters of middle-taiga bilberry-spruce forests was studied. It was found that ammonifying and oligonitrophilic microorganisms predominate in these communities. Two maximums in the population density of the microorganisms were observed in June and August. The number of microorganisms increased in the direction from the spruce trunks to the periphery of the crowns. The species composition of the micromycetes in the litters under the spruce crowns and within the intercrown spaces differed. The maximum population density of the fungi was found in the litter under the periphery of the spruce crowns, whereas the maximum diversity of the micromycetes was observed within the intercrown spaces. The Trichoderma, Trichosporiella, Penicillium, Paecilomyces, and Chaetomium genera were most abundant in the litters of the bilberry spruce forests. The Penicillium genus had the maximum abundance during the entire growing period, and the amount of Mycelia sterilia increased in the fall. The maximum diversity of the fungi was observed in May and June.

  2. Spruce budworm returns to the northeast

    Treesearch

    Lloyd Irland; William H. McWilliams

    2014-01-01

    Spruce and balsam fir supply a wealth of timber and other benefits across the northern tier of the Northeastern United States. This article is the second of a two-part series that provides an update on spruce and fir for the four Northem Forest states (Maine, New Hampshire, New York, and Vermont) using the latest Forest Inventory and Analysis (FIA) results (2012). Part...

  3. Establishment and growth of white spruce on a boreal forest floodplain: interactions between microclimate and mammalian herbivory

    Treesearch

    Amy C. Angell; Knut Kielland

    2009-01-01

    White spruce (Picea glauca (Moench) Voss) is a dominant species in late-successional ecosystems along the Tanana River, interior Alaska, and the most important commercial timber species in these boreal floodplain forests. Whereas white spruce commonly seed in on young terraces in early primary succession, the species does not become a conspicuous...

  4. Atmospheric nitrous oxide uptake in boreal spruce forest soil

    NASA Astrophysics Data System (ADS)

    Siljanen, Henri; Welti, Nina; Heikkinen, Juha; Biasi, Christina; Martikainen, Pertti

    2017-04-01

    Nitrous oxide (N2O) uptake from the atmosphere has been found in forest soils but environmental factors controlling the uptake and its atmospheric impact are poorly known. We measured N2O fluxes over growing season in a boreal spruce forest having control plots and plots with long nitrogen fertilization history. Also methane (CH4) fluxes were measured to compare the atmospheric impact of N2O and CH4fluxes. Soil chemical and physical characteristics and climatic conditions were measured as background data. Nitrous oxide consumption and uptake mechanisms were measured in complementary laboratory incubation experiments using stable isotope approaches. Gene transcript numbers of nitrous oxide reductase (nosZ) I and II genes were quantified along the incubation with elevated N2O atmosphere. The spruce forests without fertilization history showed highest N2O uptake rates whereas pine forest had low emissions. Nitrous oxide uptake correlated positively with soil moisture, high soil silt content, and low temperature. Nitrous oxide uptake varied seasonally, being highest in spring and autumn when temperature was low and water content was high. The spruce forest was sink for CH4.Methane fluxes were decoupled from the N2O fluxes (i.e. when the N2O uptake was high the CH4 uptake was low). By using GWP approach, the cooling effect of N2O uptake was on average 30% of the cooling effect of CH4 uptake in spruce forest without fertilization. Anoxic conditions promoted higher N2O consumption rates in all soils. Gene transcription of nosZ-I genes were activated at beginning of the incubation. However, atypical/clade-II nosZ was not detected. These results suggests, that also N2O uptake rates have to be considered when accounting for the GHG budget of spruce forests.

  5. Scaling approach of terrestrial carbon cycle over Alaska's black spruce forests: a synthesis of field observation, remote sensing, and ecosystem modeling

    NASA Astrophysics Data System (ADS)

    Ueyama, M.; Date, T.; Harazono, Y.; Ichii, K.

    2007-12-01

    Spatio-temporal scale up of the eddy covariance data is an important challenge especially in the northern high latitude ecosystems, since continuous ground observations are rarely conducted. In this study, we measured the carbon fluxes at a black spruce forest in interior Alaska, and then scale up the eddy covariance data to spatio- temporal variations in regional carbon budget by using satellite remote sensing data and a process based ecosystem model, Biome-BGC. At point scale, both satellite-based empirical model and Biome-BGC could reproduce seasonal and interannual variations in GPP/RE/NEE. The magnitude of GPP/RE is also consistent among the models. However, spatial patterns in GPP/RE are something different among the models; high productivity in low elevation area is estimated by the satellite-based model whereas insignificant relationship is simulated by Biome-BGC. Long- term satellite records, AVHRR and MODIS, show the gradual decline of NDVI in Alaska's black spruce forests between 1981 and 2006, resulting in a general trend of decreasing GPP/RE for Alaska's black spruce forests. These trends are consistent with the Biome-BGC simulation. The trend of carbon budget is also consistent among the models, where the carbon budget of black spruce forests did not significantly change in the period. The simulated results suggest that the carbon fluxes in black spruce forests could be more sensitive to water availability than air temperature.

  6. CO2 flux studies of different hemiboreal forest ecosystems

    NASA Astrophysics Data System (ADS)

    Krasnova, Alisa; Krasnov, Dmitrii; Noe, Steffen M.; Uri, Veiko; Mander, Ülo; Niinemets, Ülo; Soosaar, Kaido

    2017-04-01

    Hemiboreal zone is a transition between boreal and temperate zones characterized by the combination of climatic and edaphic conditions inherent in both zones. Hemiboreal forests are typically presented by mixed forests types with different ratios of deciduous and conifer tree species. Dominating tree species composition affects the functioning of forest ecosystem and its influence on biogeochemical cycles. We present the result of ecosystem scale CO2 eddy-covariance fluxes research conducted in 4 ecosystems (3 forests sites and 1 clear-cut area) of hemiboreal zone in Estonia. All 4 sites were developing under similar climatic conditions, but different forest management practices resulted in different composition of dominating tree species: pine forest with spruce trees as a second layer (Soontaga site); spruce/birch forest with single alder trees (Liispõllu site); forest presented by sectors of pine, spruce, birch and clearcut areas (SMEAR Estonia site); 5-years old clearcut area (Kõnnu site).

  7. Management of western Hemlock-sitka spruce forests for timber production.

    Treesearch

    Robert H. Ruth; A.S. Harris

    1979-01-01

    Ecological and management information for the coastal western hemlock-Sitka spruce forests is summarized in this report. Areas of emphasis include logging methods, silvicultural systems, natural and artificial regeneration, residue disposal, weed control, thinning, growth and yield, and forest protection. Consideration is given site protection and nontimber values as...

  8. Decomposition of soil organic matter from boreal black spruce forest: environmental and chemical controls

    Treesearch

    Kimberly P. Wickland; Jason C. Neff

    2007-01-01

    Black spruce forests are a dominant covertype in the boreal forest region, and they inhabit landscapes that span a wide range of hydrologic and thermal conditions. These forests often have large stores of soil organic carbon. Recent increases in temperature at northern latitudes may be stimulating decomposition rates of this soil carbon. It is unclear, however, how...

  9. Two-dimensional wavelet analysis of spruce budworm host basal area in the Border Lakes landscape

    Treesearch

    Patrick M. James; Brian R. Sturtevant; Phil Townsend; Pete Wolter; Marie-Josee Fortin

    2011-01-01

    Increases in the extent and severity of spruce budworm (Choristoneura fumiferana Clem.) outbreaks over the last century are thought to be the result of changes in forest structure due to forest management. A corollary of this hypothesis is that manipulations of forest structure and composition can be used to reduce future forest vulnerability....

  10. Tamarack and black spruce adventitious root patterns are similar in their ability to estimate organic layer depths in northern temperate forests

    Treesearch

    Timothy J. Veverica; Evan S. Kane; Eric S. Kasischke

    2012-01-01

    Organic layer consumption during forest fires is hard to quantify. These data suggest that the adventitious root methods developed for reconstructing organic layer depths following wildfires in boreal black spruce forests can also be applied to mixed tamarack forests growing in temperate regions with glacially transported soils.

  11. Optimal uneven-aged stocking guides: an application to spruce-fir stands in New England

    Treesearch

    Jeffrey H. Gove; Mark J. Ducey

    2014-01-01

    Management guides for uneven-aged forest stands periodically need to be revisited and updated based on new information and methods. The current silvicultural guide for uneven-aged spruce-fir management in Maine and the northeast (Frank, R.M. and Bjorkbom, J.C. 1973 A silvicultural guide for spruce-fir in the northeast. General Technical Report NE-6, Forest Service. U.S...

  12. Classification, description, and dynamics of plant communities after fire in the taiga of interior Alaska.

    Treesearch

    M. Joan Foote

    1983-01-01

    One hundred thirty forest stands ranging in age from I month postfire to 200 years were sampled and described by successional series (white spruce and black spruce) and by developmental stage (newly burned, moss-herb, tall shrub-sapling, dense tree, hardwood, and spruce). Patterns of change in the two successional series are described. In addition, 12 mature forest...

  13. Early red spruce restoration research by the Appalachian Forest Experiment Station, 1922-1954

    Treesearch

    James S. Rentch; Thomas M. Schuler

    2017-01-01

    This photograph (Fig. 1), taken in June of 1923 by E.S. Ship, depicts a red spruce (Picea rubens) stand with advanced reproduction near the summit of Mount Mitchell in the Pisgah National Forest of North Carolina. According to Hopkins (1899), the original extent of red spruce encompassed as much as 1,500,000 ac in the southern Appalachians; by 1895...

  14. Spruce-fir management and spruce budworm; SAF region VI technical conference

    Treesearch

    Daniel Schmitt; ed.

    1985-01-01

    Presents a technical update of the management of spruce-fir forests. Integrated management of eastern spruce budworm is not yet a reality. The ecological, social, and economic knowledge needed to develop an integrated management system is not available. The conference was designed to move individuals to a higher level of spruce budworm management in the eastern spruce-...

  15. Incidental captures of Eastern Spotted Skunk in a high-elevation Red Spruce forest in Virginia

    USGS Publications Warehouse

    Diggins, Corinne A.; Jachowski, David S.; Martin, Jay; Ford, W. Mark

    2015-01-01

    Spilogale putorius (Eastern Spotted Skunk) is considered rare in the southern Appalachian Mountains and throughout much of its range. We report incidental captures of 6 Eastern Spotted Skunks in a high-elevation Picea rubens (Red Spruce) forest in southwestern Virginia during late February and March 2014. At 1520 m, these observations are the highest-elevation records for Eastern Spotted Skunk in the Appalachian Mountains. They are also the first known records of this species using Red Spruce forests in the southern Appalachians.

  16. Chemical properties of litter inputs and organic matter along the Canadian Boreal Forest Transect Case Study

    NASA Astrophysics Data System (ADS)

    Preston, C. M.; Bhatti, J. S.; Norris, C. E.; Quideau, S. A.; Arevalo, C.

    2012-04-01

    To improve prediction of climate change impacts on the carbon balance of boreal forests, we are investigating C stocks, fluxes and organic matter quality of jack pine (Pinus banksiana) and black spruce (Picea mariana) stands in northern Saskatchewan and Manitoba along the Boreal Forest Transect Case Study (BFTCS). Jack pine stands occupy well-drained sandy soils with thin forest floor, whereas poorly-drained black spruce stands have a thick moss-dominated forest floor. Carbon storage for jack pine and black spruce stands respectively was 3.0-5.5 kg m-2 and 5.2-8.2 kg m-2 in vegetation, and 0.20-0.85 kg m-2 and 0.12-0.40 kg m-2 in coarse woody debris. Forest floor C stock was much higher for black spruce (6.0-12.7 kg m-2) than for jack pine (0.6-0.82 kg m-2). Mineral soil C to 50 cm was also significantly higher for black spruce (3.3-12.5 kg m-2) than for jack pine sites (2.2-3.0 kg m-2). Black spruce forest floor properties indicate hindered decomposition and N cycling, with high C/N ratios, strongly stratified and depleted ^13C and ^15N values, high tannins and phenolics, and 13C nuclear magnetic resonance (NMR) spectra typical of poorly decomposed plant material, especially roots and mosses. The thinner jack pine forest floor appears to be dominated by lichen, with charcoal in some samples. These contrasts are unlikely due to the small differences in aboveground litter inputs (110 vs 121 g m-2) for jack pine and black spruce respectively, 2000-2010 means) or litter quality. Development of colder, wetter and thicker black spruce forest floor is more likely associated with soil texture and drainage, further exacerbated by increasing sphagnum coverage and forest floor depth. This suggests that small environmental changes could trigger large C losses through enhanced forest floor decomposition. An investigation of mineral soil C stabilization in four jack pine sites showed that silt plus clay accounted for 15-43 % of 0-1 m C (1.5-2.8 kg m-2); silt held 0.9-3.3% of horizon mass and 13-31% of total C. Carbon-13 NMR of HF-treated silt fractions showed that alkyl and O-alkyl C dominated the A and B horizons, but C-horizon samples were higher in aromatic C, possibly of fire origin. HCl hydrolysis was used to to isolate older C, but most 14C dates were modern, with five samples from deeper horizons ranging from 141-5184 ybp. HCl residues were mainly alkyl and aromatic C. Especially for black spruce stands, soil C appears to be dominated by inputs from roots and moss, and stabilized mainly by environmental factors; soil C stored as thick forest floor is also vulnerable to loss by fire. Forest floor and mineral soil show evidence of pyrogenic C, but quantitative data are lacking to assess its role in long-term C sequestration. Considering the sensitivity of this region to climate change, further research should focus on understanding the processes controlling climate, vegetation and soil interactions throughout the lifecycle of jack pine and black spruce forests.

  17. Effects of ammonium on elemental nutrition of red spruce and indicator plants grown in acid soil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoelldampf, B.; Barker, A.V.

    Decline of high elevation red spruce forests in the northeastern United States has been related to acid rain, particularly with respect to the deposition of nitrogenous materials. Ca and Mg deficiencies may be induced by input of air-borne nitrogenous nutrients into the forest ecosystem. This research investigated the effects of N nutrition on mineral nutrition of red spruce and radish, as an indicator plant, grown in acid forest soil. Red spruce and radishes in the greenhouse were treated with complete nutrient solutions with 15 mM N supplied as 0, 3.75, 7.5, 11.25, or 15 mM NH[sub 4][sup +] with themore » remainder being supplied as NO[sub 3][sup [minus

  18. Crafting a competitive edge: white spruce regeneration in Alaska.

    Treesearch

    Jonathan. Thompson

    2005-01-01

    Over the past two decades, unprecedented levels of disturbance have occurred in the white spruce forests of Alaska. Spruce bark beetles, fires, and timber harvests have left millions of acres of dead spruce with little spruce regeneration. To assist public and private landowners, Pacific Northwest Research (PNW) Station scientists are testing various approaches to...

  19. Release of suppressed red spruce using canopy gap creation—Ecological restoration in the Central Appalachians

    USGS Publications Warehouse

    Rentch, J.S.; Ford, W. Mark; Schuler, T.S.; Palmer, J.; Diggins, Corinne A.

    2016-01-01

    Red spruce (Picea rubens) and red spruce-northern hardwood mixed stands once covered as much as 300,000 ha in the Central Appalachians, but now comprise no more than 21,000 ha. Recently, interest in restoration of this forest type has increased because red spruce forests provide habitat for a number of rare animal species. Our study reports the results of an understory red spruce release experiment in hardwood-dominated stands that have a small component of understory red spruce. In 2005, 188 target spruce were identified in sample plots at six locations in central West Virginia. We projected a vertical cylinder above the crown of all target spruces, and in 2007, we performed a release treatment whereby overtopping hardwoods were treated with herbicide using a stem injection technique. Release treatments removed 0–10% (Control), 11–50% (Low), 51–89% (Medium), and ≤90% (High) of the basal area of overtopping trees. We also took canopy photographs at the time of each remeasurement in 2007, 2010, and 2013, and compared basal removal treatments and resulting 2010 canopy openness and understory light values. The high treatment level provided significantly greater six-year dbh and height growth than the other treatment levels. Based on these results, we propose that a tree-centered release approach utilizing small canopy gaps that emulate the historical, gap-phase disturbance regime provides a good strategy for red spruce restoration in hardwood forests where overstory spruce are virtually absent, and where red spruce is largely relegated to the understory.

  20. SPRUCE S1 Bog and SPRUCE Experiment Location Survey Results, 2015

    DOE Data Explorer

    Griffiths, Natalie A. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.; Hook, L. A. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.; Hanson, P. J. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.

    2016-01-01

    This data set provides a record of the horizontal and vertical survey results of SPRUCE experimental infrastructure and measurement locations on the S1-Bog on the Marcell Experimental Forest and the SPRUCE experimental site within the S1-Bog.

  1. Ecology and silviculture of the spruce-fir forests of eastern North America

    Treesearch

    Marinus Westveld

    1953-01-01

    Using the climax forest as a guide to growing the species best suited to the climate and the site, the author offers a silvicultural system for managing the spruce-fir forests of eastern North America. Based on ecological principles, such silviculture is aimed to bring about forests that are inherently healthy and have a natural resistance to insects and disease.

  2. Mortality of spruce and fir in Maine in 1976-78 due to the spruce budworm outbreak

    Treesearch

    Donald W. Seegrist; Stanford L. Arner

    1982-01-01

    The spruce budworm population in Maine's spruce-fir forests has been at epidemic levels since the early 1970's. Spruce-fir mortality in 1976-78 is compared with predictions of what mortality would have been had the natural mortality rates remained at the levels experienced before the budworm outbreak. It appears that mortality of spruce and fir has increased...

  3. Species composition and stand structure of a large red spruce planting 67 years after its establishment in western North Carolina

    Treesearch

    W. Henry McNab; James H. Holbrook; Ted M. Oprean

    2010-01-01

    Red spruce (Picea rubens Michx.) is a large and long-lived species that dominated high-elevation forests of the southern Appalachians before most stands were heavily logged in the early 1900s. Restoration of spruce forests by artificial methods has been studied since the 1920s, but little information is available on characteristics of older planted...

  4. Impacts of fire on non-native plant recruitment in black spruce forests of interior Alaska.

    PubMed

    Walker, Xanthe J; Frey, Matthew D; Conway, Alexandra J; Jean, Mélanie; Johnstone, Jill F

    2017-01-01

    Climate change is expected to increase the extent and severity of wildfires throughout the boreal forest. Historically, black spruce (Picea mariana (Mill.) B.S.P.) forests in interior Alaska have been relatively free of non-native species, but the compounding effects of climate change and an altered fire regime could facilitate the expansion of non-native plants. We tested the effects of wildfire on non-native plant colonization by conducting a seeding experiment of non-native plants on different substrate types in a burned black spruce forest, and surveying for non-native plants in recently burned and mature black spruce forests. We found few non-native plants in burned or mature forests, despite their high roadside presence, although invasion of some burned sites by dandelion (Taraxacum officinale) indicated the potential for non-native plants to move into burned forest. Experimental germination rates were significantly higher on mineral soil compared to organic soil, indicating that severe fires that combust much of the organic layer could increase the potential for non-native plant colonization. We conclude that fire disturbances that remove the organic layer could facilitate the invasion of non-native plants providing there is a viable seed source and dispersal vector.

  5. Population response of the northern red-backed vole (Clethrionomys rutilus) to differentially cut white spruce forest.

    Treesearch

    Stephen D. West; R. Glenn Ford; John C. Zasada

    1980-01-01

    The population response of the northern red-backed vole (Clethrionomys rutilus) to a differentially cut white spruce (Picea glauca) forest 30 km southwest of Fairbanks, Alaska, was monitored by simultaneous livetrapping in a clearcut, in a partially cut or shelterwood area, and in an area of uncut forest. During the first...

  6. Growth and yield of sitka spruce and western hemlock at Cascade Head Experimental Forest, Oregon.

    Treesearch

    Stephen H. Smith; John F. Bell; Francis R. Herman; Thomas See

    1984-01-01

    A study established in 83-year-old, even-aged stands of Sitka spruce (Picea sitchensis (Bong.) Carr.) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) at Cascade Head Experimental Forest in the Siuslaw National Forest on the Oregon coast traces their development for 33 years. Statistical data collected from 12 permanent...

  7. 25+ year changes in forest structure and tree-ring patterns in three old-growth red spruce stands in West Virginia

    Treesearch

    Eric Heitzman; Sean Doughterty; James Rentch; Steve Adams; Steve. Stephenson

    2010-01-01

    The extent of red spruce (Picea rubens) forests in West Virginia has dramatically declined from an estimated 1.5 million acres in 1865 to 30,000 acres today because of widespread logging and forest fires during the late 1800s and early 1900s.

  8. Western spruce budworm defoliation effects on forest structure and potential fire behavior.

    Treesearch

    S. Hummel; J.K. Agee

    2003-01-01

    Forest composition and structure on the eastern slope of the Cascade Mountains have been influenced by decades of fire exclusion. Multilayered canopies and high numbers of shade-tolerant true fir trees interact with western spruce budworm to alter forest structure and to affect potential fire behavior and effects. We compared...

  9. Changes in canopy cover alter surface air and forest floor temperature in a high-elevation red spruce (Picea rubens Sarg.) forest

    Treesearch

    Johnny L. Boggs; Steven G. McNulty

    2010-01-01

    The objective of this study is to describe winter and summer surface air and forest floor temperature patterns and diurnal fluctuations in high-elevation red spruce (Picea rubens Sarg.) forests with different levels of canopy cover. In 1988, a series of 10- x 10-meter plots (control, low nitrogen [N] addition, and high nitrogen addition) were...

  10. A 4-year record of sitka spruce and western hemlock seed fall on the Cascade Head Experimental Forest.

    Treesearch

    Robert H. Ruth; Carl M. Berntsen

    1955-01-01

    Four years' measurement of seed fall in the spruce-hemlock type on the Cascade Head Experimental Forest indicates that an ample supply of seed is distributed over clear-cut areas under staggered-setting cutting. The largest tract sampled was 81 acres; in spite of a seed crop failure in 1950, it received an average of 243,000 viable spruce and hemlock seeds per...

  11. Patterns of total ecosystem carbon storage with changes in soil temperature in boreal black spruce forests

    Treesearch

    E.S. Kane; J.G. Vogel

    2009-01-01

    To understand how carbon (C) pools in boreal ecosystems may change with warming, we measured above- and belowground C pools and C increment along a soil temperature gradient across 16 mature upland black spruce (Picea mariana Mill. [B•S.P]) forests in interior Alaska. Total spruce C stocks (stand and root C) increased from 1.3 to 8.5 kg C m

  12. Mountain Climates on the Move: Implications for Past and Future Vegetation Shifts in the Northeastern United States

    NASA Astrophysics Data System (ADS)

    Wason, J. W., III; Dovciak, M.; Bevilacqua, E.

    2015-12-01

    Climate change in the northeastern United States is expected to shift climatic (temperature) envelopes for spruce-fir forests upslope and northward decreasing their area in the region by 2100. Coarse scale landscape models however, may not incorporate heterogeneity in climatic conditions in mountains that can create climatic refugia for species in high-elevation spruce-fir forests. To determine spatial and temporal trends in climate of mountain spruce-fir forests we measured microclimate at 98 forest plots in 2012 and 2013 on 12 mountains in New York, Vermont, New Hampshire, and Maine. By linking regional climate trends with our spatial climate data we calculated elevational shifts in temperature envelopes during the last 50 years. Additionally we linked our spatial dataset to a range of future climate conditions for 2100 based on Representative Concentration Pathways (1 to 5°C warming). We hypothesized that climates have already changed to an extent that spruce-fir forests should begin to respond and that future climate conditions may shift suitable habitat for spruce-fir forests beyond their current range. We found that regional climate change over the last 50 years has resulted in warming of 0.66 and 1.62°C for average annual daily maximum (Tmax) and minimum (Tmin) temperatures in the region. When linked to our spatial microclimate model, this warming results in a 100 (Tmax) and 312m (Tmin) upslope shift in temperature envelopes. Future climate projections suggest that by 2100 Tmax may shift upslope between 152 and 758m for the 1 and 5°C scenarios respectively, while Tmin may shift upslope between 192 and 962m. Spruce-fir forests typically occupy an elevation range of ~500m suggesting that the climate experienced in these forests 50 years ago may not be found within their elevation range by 2100. These results are discussed in the context of responses of tree populations and growth rates observed along the elevation gradients of northeastern United States.

  13. Spruce aphid, Elatobium abietinum (Walker): Life history and damage to Engelmann spruce in the Pinaleno Mountains, Arizona

    Treesearch

    Ann M. Lynch

    2009-01-01

    Spruce aphid is an exotic insect recently introduced to the Pinaleno Mountains. It feeds on dormant Engelmann spruce, and possible effects include tree-growth suppression, tree mortality, and reduction in seed and cone production. Potential longer-term effects include changes in forest structure and species composition - primarily through reduction in Engelmann spruce...

  14. Succession change of microorganisms on plant waste decomposition in simulation modelling field experiment

    NASA Astrophysics Data System (ADS)

    Vinogradova, Julia; Perminova, Evgenia; Khabibullina, Fluza; Kovaleva, Vera; Lapteva, Elena

    2016-04-01

    Plant waste decomposition processes are closely associated with living activity of soil microbiota in aboveground ecosystems. Functional activity of microorganisms and soil invertebrates determines plant material transformation rate whereby changes in plant material chemical composition during destruction - succession change of soil biota. The purpose of the work was revealing the mechanism of microorganisms succession change during plant waste decomposition in middle-taiga green-moss spruce forests and coniferous-deciduous secondary stands formed after earlier cut bilberry spruce forests. The study materials were undisturbed bilberry spruce forest (Sample Plot 1 - SP1) and coniferous-deciduous secondary stands which were formed after tree cutting activities of 2001-2002 (SP2) and 1969 and 1970 (SP3). Plant material decomposition intensity was determined in microcosms isolated into kapron bags with cell size of 1 mm. At SP1 and SP2, test material was living mosses and at SP3 - fallen birch and aspen leaves. Every test material was exposed for 2 years. Destruction rate was calculated as a weight loss for a particular time period. Composition of micromycetes which participated in plant material decomposition was assessed by the method of inoculation of soil extract to Getchinson's medium and acidified Czapek's medium (pH=4.5). Microbe number and biomass was analyzed by the method of luminescent microscopy. Chemical analysis of plant material was done in the certified Ecoanalytical Laboratory of the Institute of Biology Komi SC UrD RAS. Finally, plant material destruction intensity was similar for study plots and comprised 40-44 % weight loss for 2 years. The strongest differences in plant material decomposition rate between undisturbed spruce forests and secondary after-cut stands were observed at first stages of destruction process. In the first exposition year, mineralizing processes were most active in undisturbed spruce forest. Decomposition rate in cuts at that period was less by a factor of 1.7-2.3. The highest diversity of moss-decomposing micromycetes (30 species of microscopic fungi of 13 genera) was found for undisturbed spruce forest (SP1). At cuts, the figures were 17 and 23 species of micromycetes, correspondingly. Succession change in composition of micromycetes was best pronounced in undisturbed spruce forest. At cuts, there was no clear mechanism of micromycetes species diversity change during plant waste decomposition. This could serve an anthropogenic disturbance marker of taiga ecosystems. Generally, microscopic moss- and leaf-decomposing fungi at all plots were very species specific. Total biomass of microorganisms in microcosms at cuts was less than that at undisturbed spruce forest by 1.4-1.6 time. Its structure was dominated by mycelium and fungal spores (98-99 % total biomass). On leaf waste decomposition (SP3), microbe biomass got more bacteria. By the obtained data, undisturbed middle-taiga spruce forests have better conditions for living activity of plant waste-decomposing microscopic fungi. This is evidenced by less species diversity of microscopic fungi, shorter length and less biomass of mycelium at cuts as compared with undisturbed spruce forests.

  15. Spruce Budworm in the Eastern United States

    Treesearch

    Daniel R. Kuceral; Peter W. Orr

    The spruce budworm Choristoneura fumiferana (Clemens) is one of the most destructive native insects in the northern spruce and fir forests of the Eastern United States and Canada. Periodic outbreaks of the spruce budworm are a part of the natural cycle of events associated with the maturing of balsam fir.

  16. Spruce aphid in high elevation habitats in the Southwest U.S.

    Treesearch

    Ann M. Lynch

    2003-01-01

    Spruce aphid, Elatobium abietinum (Walker) (Homoptera: Aphididae), is a new invasive pest in the interior Southwestern United States. This insect is causing extensive and severe damage on dormant Engelmann spruce, Picea engelmannii Parry, and Colorado blue spruce, P. pungens Engelm., in high elevation forests in...

  17. Revisiting Pearson's climate and forest type studies on the Fort Valley Experimental Forest

    Treesearch

    Joseph E. Crouse; Margaret M. Moore; Peter Fule

    2008-01-01

    Five weather station sites were established in 1916 by Fort Valley personnel along an elevational gradient from the Experimental Station to near the top of the San Francisco Peaks to investigate the factors that controlled and limited forest types. The stations were located in the ponderosa pine, Douglas-fir, limber pine, Engelmann spruce, and Engelmann spruce/...

  18. Forest health restoration in south-central Alaska: a problem analysis.

    Treesearch

    Darrell W. Ross; Gary E. Daterman; Jerry L. Boughton; Thomas M. Quigley

    2001-01-01

    A spruce beetle outbreak of unprecedented size and intensity killed most of the spruce trees on millions of acres of forest land in south-central Alaska in the 1990s. The tree mortality is affecting every component of the ecosystem, including the socioeconomic culture dependent on the resources of these vast forests. Based on information obtained through workshops and...

  19. Revisiting Pearson's climate and forest type studies on the Fort Valley Experimental Forest (P-53)

    Treesearch

    Joseph E. Crouse; Margaret M. Moore; Peter Z. Fule

    2008-01-01

    Five weather station sites were established in 1916 by Fort Valley personnel along an elevational gradient from the Experimental Station to near the top of the San Francisco Peaks to investigate the factors that controlled and limited forest types. The stations were located in the ponderosa pine, Douglas-fir, limber pine, Engelmann spruce, and Engelmann spruce/...

  20. Susceptibility of burned black spruce (Picea mariana) forests to non-native plant invasions in interior Alaska

    Treesearch

    Katie V. Spellman; Christa P.H. Mulder; Teresa N. Hollingsworth

    2014-01-01

    As climate rapidly warms at high-latitudes, the boreal forest faces the simultaneous threats of increasing invasive plant abundances and increasing area burned by wildfire. Highly flammable and widespread black spruce (Picea mariana) forest represents a boreal habitat that may be increasingly susceptible to non-native plant invasion. This study assess the role of burn...

  1. Dynamics of calcium concentration in stemwood of red spruce and Siberian fir

    Treesearch

    Kevin T. Smith; Walter C. Shortle; Rakesh Minocha; Vladislav A. Alexeyev

    1996-01-01

    The atmospheric deposition of strong acid anions such as sulfate and nitrate shifts the ion exchange equilibrium in the rooting zone of sensitive forests. Red spruce and other northern coniferous forests are especially sensitive to deposition due to the shallow rooting of trees in a mor-type forest floor. Initially, the deposition of strong acid ions mobilizes...

  2. Spruce-fir forest changes during a 30-year nitrogen saturation experiment

    Treesearch

    Steven G. McNulty; Johnny L. Boggs; John D. Aber; Lindsey E. Rustad

    2017-01-01

    A field experiment was established in a high elevation red spruce (Picea rubens Sarg.) – balsam fir (Abies balsamea) forest on Mount Ascutney Vermont, USA in 1988 to test the nitrogen (N) saturation hypothesis, and to better understand the mechanisms causing forest decline at the time. The study established replicate control, lowand high dose nitrogen addition plots (i...

  3. Ecophysiology of seedling establishment in contrasting spruce-fir forests of southern Appalachian and Rocky Mountain ecotones, USA

    Treesearch

    William K. Smith; Keith N.C. Reinhardt; Daniel M. Johnson

    2010-01-01

    Fraser fir (Abies fraseri [Pursh] Poiret) and red spruce (Picea rubens Sarg.) occur as codominant trees in six relic, mountain-top populations that make up the high-elevation forests of the Southern Appalachian Mountains (SA). These two relic species of the former boreal forest have experienced a significant decline over the past...

  4. Effects of bark beetle attack on canopy fuel flammability and crown fire potential in lodgepole pine and Engelmann spruce forests

    Treesearch

    Wesley G. Page; Martin E. Alexander; Michael J. Jenkins

    2015-01-01

    Large wildland fires in conifer forests typically involve some degree of crowning, with their initiation and propagation dependent upon several characteristics of the canopy fuels. Recent outbreaks of mountain pine beetle (Dendroctonus ponderosae Hopkins) in lodgepole pine (Pinus contorta Dougl. var. latifolia E ngelm.) forests and spruce beetle (Dendroctonus...

  5. Assessment of soil calcium status in red spruce forests in the northeastern United States

    USGS Publications Warehouse

    Lawrence, G.B.; David, M.B.; Bailey, S.W.; Shortle, W.C.

    1997-01-01

    Long-term changes in concentrations of available Ca in soils of red spruce forests have been documented, but remaining questions about the magnitude and regional extent of these changes have precluded an assessment of the current and future status of soil Ca. To address this problem, soil samples were collected in 1992-93 from 12 sites in New York, Vermont, New Hampshire, and Maine to provide additional data necessary to synthesize all available research results on soil Ca in red spruce forests. Sites were chosen to encompass the range of environmental conditions experienced by red spruce. Concentrations of exchangeable Ca ranged from 2.13 to 21.6 cmol(c) kg-1 in the Oa horizon, and from 0.11 to 0.68 cmol(c) kg-1 in the upper 10 cm of the B horizon. These measurements expanded the range of exchangeable Ca reported in the literature for both horizons in northeastern red spruce forests. Exchangeable Ca was the largest Ca fraction in the forest floor at most sites (92% of acid-extractable Ca), but mineral Ca was the largest fraction at the three sites that also had the highest mineral-matter concentrations. The primary factor causing variability in Ca concentrations among sites was the mineralogy of parent material, but exchangeable concentrations in the B horizon of all sites were probably reduced by acidic deposition. Because the majority of Ca in the forest floor is in a readily leachable form, and Ca inputs to the forest floor from the mineral soil and atmospheric deposition have been decreasing in recent decades, the previously documented decreases in Ca concentrations in the forest floor over previous decades may extend into the future.

  6. Space sequestration below ground in old-growth spruce-beech forests—signs for facilitation?

    PubMed Central

    Bolte, Andreas; Kampf, Friederike; Hilbrig, Lutz

    2013-01-01

    Scientists are currently debating the effects of mixing tree species for the complementary resource acquisition in forest ecosystems. In four unmanaged old-growth spruce-beech forests in strict nature reserves in southern Sweden and northern Germany we assessed forest structure and fine rooting profiles and traits (≤2 mm) by fine root sampling and the analysis of fine root morphology and biomass. These studies were conducted in selected tree groups with four different interspecific competition perspectives: (1) spruce as a central tree, (2) spruce as competitor, (3) beech as a central tree, and (4) beech as competitor. Mean values of life fine root attributes like biomass (FRB), length (FRL), and root area index (RAI) were significantly lower for spruce than for beech in mixed stands. Vertical profiles of fine root attributes adjusted to one unit of basal area (BA) exhibited partial root system stratification when central beech is growing with spruce competitors. In this constellation, beech was able to raise its specific root length (SRL) and therefore soil exploration efficiency in the subsoil, while increasing root biomass partitioning into deeper soil layers. According to relative values of fine root attributes (rFRA), asymmetric below-ground competition was observed favoring beech over spruce, in particular when central beech trees are admixed with spruce competitors. We conclude that beech fine rooting is facilitated in the presence of spruce by lowering competitive pressure compared to intraspecific competition whereas the competitive pressure for spruce is increased by beech admixture. Our findings underline the need of spatially differentiated approaches to assess interspecific competition below ground. Single-tree approaches and simulations of below-ground competition are required to focus rather on microsites populated by tree specimens as the basic spatial study area. PMID:24009616

  7. Evidence of montane spruce-fir forest recovery on the high peaks and ridges of the black mountains, North Carolina: recent trends, 1986-2003

    Treesearch

    Todd Allen Bowers; Robert I. Bruck

    2010-01-01

    Decline in high elevation red spruce (Picea rubens Sarg.) and Fraser fir (Abies fraseri (Pursh) Poir.) forests throughout the southern Appalachians was shown following extensive surveys conducted during the 1980s.

  8. Proceedings of the ninth Lake States Forest Tree Improvement Conference, August 22-23, 1969.

    Treesearch

    USDA

    1970-01-01

    Presents nine papers concerning recent research in forest genetics, physiology, and allied fields. Species discussed include Scotch pine, red pine, jack pine, white pine, larch, white spruce, black spruce, balsam fir, yellow birch, sugar maple, red oak, American elm, and aspen.

  9. Precipitation nutrients in the open and under two forests in Minnesota

    Treesearch

    Elon S. Verry; D.R. Timmons

    1977-01-01

    Concentrations of N, P, K, Ca, Mg, and Na were measured in rain and snow in the open, and in throughfall and stemflow under black spruce and aspen forests in north-central Minnesota. Concentrations of total P in rain and black spruce throughfall were inversely related to storm size. Annual precipitation nutrient inputs to the forest floor were calculated for each site...

  10. AmeriFlux CA-Qc2 Quebec - 1975 Harvested Black Spruce (HBS75)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Margolis, Hank

    This is the AmeriFlux version of the carbon flux data for the site CA-Qc2 Quebec - 1975 Harvested Black Spruce (HBS75). Site Description - Quebec - Eastern Boreal; Black Spruce forest harvested in 1975.

  11. Red spruce restoration modeling in LANDIS

    Treesearch

    Melissa. Thomas-Van Gundy

    2010-01-01

    Scenarios for the restoration of red spruce (Picea rubens)-dominated forests on the Monongahela National Forest were created in the landscape simulation model LANDIS. The resulting landscapes were compared to existing habitat suitability index models for the Virginia northern flying squirrel (VNFS) and Cheat Mountain salamander (CMS) as a measure of...

  12. Effects of defoliation on growth of certain conifers

    Treesearch

    Thomas W., Jr. Church

    1949-01-01

    In planning forest management of spruce-fir forests in the Northeast, the possibility of recurring epidemics of the spruce budworm (Archips fumiferana) must be considered. Investigations of this insect must take into account not only the effects of defoliation on mortality, but also the growth losses that result from partial defoliation.

  13. Structure and resilience of fungal communities in Alaskan boreal forest soils

    Treesearch

    D. Lee Taylor; Ian C. Herriott; Kelsie E. Stone; Jack W. McFarland; Michael G. Booth; Mary Beth Leigh

    2010-01-01

    This paper outlines molecular analyses of soil fungi within the Bonanza Creek Long Term Ecological Research program. We examined community structure in three studies in mixed upland, black spruce (Picea mariana (Mill.) BSP), and white spruce (Picea glauca (Moench) Voss) forests and examined taxa involved in cellulose...

  14. AmeriFlux US-Prr Poker Flat Research Range Black Spruce Forest

    DOE Data Explorer

    Suzuki, Rikie [Japan Agency for Marine-Earth Science and Technology

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Prr Poker Flat Research Range Black Spruce Forest. Site Description - This site is located in a blackspruce forest within the property of the Poker Flat Research Range, University of Alaska, Fairbanks. Time-lapse image of the canopy is measured at the same time to relate flux data to satellite images.

  15. Topographic controls on black carbon accumulation in Alaskan black spruce forest soils: implications for organic matter dynamics

    Treesearch

    E.S. Kane; W.C. Hockaday; M.R. Turetsky; C.A. Masiello; D.W. Valentine; B.P. Finney; J.A. Badlock

    2010-01-01

    There is still much uncertainty as to how wildfire affects the accumulation of burn residues (such as black carbon [BC]) in the soil, and the corresponding changes in soil organic carbon (SOC) composition in boreal forests. We investigated SOC and BC composition in black spruce forests on different landscape positions in Alaska, USA. Mean BC stocks in surface mineral...

  16. Can aspen persist in conifer dominated forests?

    Treesearch

    Douglas H. Page; John D. Shaw

    2016-01-01

    In 1998 we measured a large, old aspen in a mixed spruce-fir-aspen forest on the Utah State University T.W. Daniel Experimental Forest in northern Utah. The tree was 297 years old - about the same age as the oldest spruce in the stand. A search of the forestry literature revealed that the oldest published age for an aspen came from a tree in the Sierra Nevada Range in...

  17. Fire severity unaffected by spruce beetle outbreak in spruce-fir forests in southwestern Colorado.

    PubMed

    Andrus, Robert A; Veblen, Thomas T; Harvey, Brian J; Hart, Sarah J

    2016-04-01

    Recent large and severe outbreaks of native bark beetles have raised concern among the general public and land managers about potential for amplified fire activity in western North America. To date, the majority of studies examining bark beetle outbreaks and subsequent fire severity in the U.S. Rocky Mountains have focused on outbreaks of mountain pine beetle (MPB; Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests, but few studies, particularly field studies, have addressed the effects of the severity of spruce beetle (Dendroctonus rufipennis Kirby) infestation on subsequent fire severity in subalpine Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests. In Colorado, the annual area infested by spruce beetle outbreaks is rapidly rising, while MPB outbreaks are subsiding; therefore understanding this relationship is of growing importance. We collected extensive field data in subalpine forests in the eastern San Juan Mountains, southwestern Colorado, USA, to investigate whether a gray-stage (< 5 yr from outbreak to time of fire) spruce beetle infestation affected fire severity. Contrary to the expectation that bark beetle infestation alters subsequent fire severity, correlation and multivariate generalized linear regression analysis revealed no influence of pre-fire spruce beetle severity on nearly all field or remotely sensed measurements of fire severity. Findings were consistent across moderate and extreme burning conditions. In comparison to severity of the pre-fire beetle outbreak, we found that topography, pre-outbreak basal area, and weather conditions exerted a stronger effect on fire severity. Our finding that beetle infestation did not alter fire severity is consistent with previous retrospective studies examining fire activity following other bark beetle outbreaks and reiterates the overriding influence of climate that creates conditions conducive to large, high-severity fires in the subalpine zone of Colorado. Both bark beetle outbreaks and wildfires have increased autonomously due to recent climate variability, but this study does not support the expectation that post-beetle outbreak forests will alter fire severity, a result that has important implications for management and policy decisions.

  18. Continuing Climate Warming Will Result in Failure of Post-Harvest Natural Regeneration across the Landscape in Interior Alaska

    NASA Astrophysics Data System (ADS)

    Morimoto, M.; Juday, G. P.; Huettmann, F.

    2016-12-01

    Following forest disturbance, the stand initiation stage decisively influences future forest structure. Understanding post-harvest regeneration, especially under climate change, is essential to predicting future carbon stores in this extensive forest biome. We apply IPCC B1, A1B, and A2 climate scenarios to generate plausible future forest conditions under different management. We recorded presence of white spruce, birch, and aspen in 726 plots on 30 state forest white spruce harvest units. We built spatially explicit models and scenarios of species presence/absence using TreeNet (Stochastic Gradient Boosting). Post-harvest tree regeneration predictions in calibration data closely matched the validation set, indicating tree regeneration scenarios are reliable. Early stage post-harvest regeneration is similar to post-fire regeneration and matches the pattern of long-term natural vegetation distribution, confirming that site environmental factors are more important than management practices. Post-harvest natural regeneration of tree species increases under moderate warming scenarios, but fails under strong warming scenarios in landscape positions with high temperatures and low precipitation. Under all warming scenarios, the most successful regenerating species following white spruce harvest is white spruce. Birch experiences about 30% regeneration failure under A2 scenario by 2050. White spruce and aspen are projected to regenerate more successfully when site preparation is applied. Although white spruce has been the major managed species, birch may require more intensive management. Sites likely to experience regeneration failure of current tree species apparently will experience biome shift, although adaptive migration of existing or new species might be an option. Our scenario modeling tool allows resource managers to forecast tree regeneration on productive managed sites that have made a disproportionate contribution to carbon flux in a critical region.

  19. Soil Microbial Biomass, Basal Respiration and Enzyme Activity of Main Forest Types in the Qinling Mountains

    PubMed Central

    Cheng, Fei; Peng, Xiaobang; Zhao, Peng; Yuan, Jie; Zhong, Chonggao; Cheng, Yalong; Cui, Cui; Zhang, Shuoxin

    2013-01-01

    Different forest types exert essential impacts on soil physical-chemical characteristics by dominant tree species producing diverse litters and root exudates, thereby further regulating size and activity of soil microbial communities. However, the study accuracy is usually restricted by differences in climate, soil type and forest age. Our objective is to precisely quantify soil microbial biomass, basal respiration and enzyme activity of five natural secondary forest (NSF) types with the same stand age and soil type in a small climate region and to evaluate relationship between soil microbial and physical-chemical characters. We determined soil physical-chemical indices and used the chloroform fumigation-extraction method, alkali absorption method and titration or colorimetry to obtain the microbial data. Our results showed that soil physical-chemical characters remarkably differed among the NSFs. Microbial biomass carbon (Cmic) was the highest in wilson spruce soils, while microbial biomass nitrogen (Nmic) was the highest in sharptooth oak soils. Moreover, the highest basal respiration was found in the spruce soils, but mixed, Chinese pine and spruce stands exhibited a higher soil qCO2. The spruce soils had the highest Cmic/Nmic ratio, the greatest Nmic/TN and Cmic/Corg ratios were found in the oak soils. Additionally, the spruce soils had the maximum invertase activity and the minimum urease and catalase activities, but the maximum urease and catalase activities were found in the mixed stand. The Pearson correlation and principle component analyses revealed that the soils of spruce and oak stands obviously discriminated from other NSFs, whereas the others were similar. This suggested that the forest types affected soil microbial properties significantly due to differences in soil physical-chemical features. PMID:23840671

  20. Can a bog drained for forestry be a stronger carbon sink than a natural bog forest?

    NASA Astrophysics Data System (ADS)

    Hommeltenberg, J.; Schmid, H. P.; Drösler, M.; Werle, P.

    2014-07-01

    This study compares the CO2 exchange of a natural bog forest, and of a bog drained for forestry in the pre-Alpine region of southern Germany. The sites are separated by only 10 km, they share the same soil formation history and are exposed to the same climate and weather conditions. In contrast, they differ in land use history: at the Schechenfilz site a natural bog-pine forest (Pinus mugo ssp. rotundata) grows on an undisturbed, about 5 m thick peat layer; at Mooseurach a planted spruce forest (Picea abies) grows on drained and degraded peat (3.4 m). The net ecosystem exchange of CO2 (NEE) at both sites has been investigated for 2 years (July 2010-June 2012), using the eddy covariance technique. Our results indicate that the drained, forested bog at Mooseurach is a much stronger carbon dioxide sink (-130 ± 31 and -300 ± 66 g C m-2 a-1 in the first and second year, respectively) than the natural bog forest at Schechenfilz (-53 ± 28 and -73 ± 38 g C m-2 a-1). The strong net CO2 uptake can be explained by the high gross primary productivity of the 44-year old spruces that over-compensates the two-times stronger ecosystem respiration at the drained site. The larger productivity of the spruces can be clearly attributed to the larger plant area index (PAI) of the spruce site. However, even though current flux measurements indicate strong CO2 uptake of the drained spruce forest, the site is a strong net CO2 source when the whole life-cycle since forest planting is considered. It is important to access this result in terms of the long-term biome balance. To do so, we used historical data to estimate the difference between carbon fixation by the spruces and the carbon loss from the peat due to drainage since forest planting. This rough estimate indicates a strong carbon release of +134 t C ha-1 within the last 44 years. Thus, the spruces would need to grow for another 100 years at about the current rate, to compensate the potential peat loss of the former years. In contrast, the natural bog-pine ecosystem has likely been a small but stable carbon sink for decades, which our results suggest is very robust regarding short-term changes of environmental factors.

  1. Evaluating the Suitability of Management Strategies of Pure Norway Spruce Forests in the Black Forest Area of Southwest Germany for Adaptation to or Mitigation of Climate Change

    NASA Astrophysics Data System (ADS)

    Yousefpour, Rasoul; Hanewinkel, Marc; Le Moguédec, Gilles

    2010-02-01

    The study deals with the problem of evaluating management strategies for pure stands of Norway spruce ( Picea abies Karst) to balance adaptation to and mitigation of climate change, taking into account multiple objectives of a forest owner. A simulation and optimization approach was used to evaluate the management of a 1000 ha model Age-Class forest, representing the age-class distribution of an area of 66,000 ha of pure Norway spruce forests in the Black Forest region of Southwest Germany. Eight silvicultural scenarios comprising five forest conversion schemes which were interpreted as “adaptation” strategies which aims at increasing the proportion of Beech, that is expected to better cope with climate change than the existing Norway spruce, and three conventional strategies including a “Do-nothing” alternative classified as “mitigation”, trying to keep rather higher levels of growing stock of spruce, were simulated using the empirical growth simulator BWINPro-S. A linear programming approach was adapted to simultaneously maximize the net present values of carbon sequestration and timber production subject to the two constraints of wood even flow and partial protection of the oldest (nature protection). The optimized plan, with the global utility of 11,687 €/ha in forty years, allocated a combination of silvicultural scenarios to the entire forest area. Overall, strategies classified as “mitigation” were favored, while strategies falling into the “adaptation”-category were limited to the youngest age-classes in the optimal solution. Carbon sequestration of the “Do-nothing” alternative was between 1.72 and 1.85 million tons higher than the other alternatives for the entire forest area while the differences between the adaptation and mitigation approaches were approximately 133,000 tons. Sensitivity analysis showed that a carbon price of 21 €/ t is the threshold at which carbon sequestration is promoted, while an interest rate of above 2% would decrease the amount of carbon.

  2. Coarse woody debris in a southern Appalachian spruce-fir forest of the Great Smoky Mountains National Park

    Treesearch

    Anita Rose; N.S. Nicholas

    2009-01-01

    Spruce-fir forests in the southern Appalachian Mountains receive high atmospheric nitrogen inputs and have high nitrate levels in soil solution and streamwater. High levels of excess nitrogen have been associated with reduced tree vigor. Additionally, the balsam woolly adelgid (Adelges piceae Ratz.) has killed the...

  3. Rates of forest floor decomposition and nutrient turnover in aspen, pine, and spruce stands on two soils.

    Treesearch

    D. A. Perala; D.H. Alban

    1982-01-01

    Compares rates of forest floor decomposition and nutrient turnover in aspen and conifers. These rates were generally most rapid under aspen, slowest under spruce, and more rapid on a loamy fine sand than on a very fine sandy loam. Compares results with literature values.

  4. 78 FR 46312 - Spruce Beetle Epidemic and Aspen Decline Management Response; Grand Mesa, Uncompahgre and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... providing for human safety. Treatments would be carried out on National Forest System (NFS) Lands within the scope of direction provided in the GMUG Revised Land and Resource Management Plan. DATES: To be most... DEPARTMENT OF AGRICULTURE Forest Service Spruce Beetle Epidemic and Aspen Decline Management...

  5. Physiological and environmental causes of freezing injury in red spruce

    Treesearch

    Paul G. Schaberg; Donald H. DeHayes

    2000-01-01

    For many, concerns about the implications of "environmental change" conjure up scenarios of forest responses to global warming, enrichment of greenhouse gases, such as carbon dioxide and methane, and the northward migration of maladapted forests. From that perspective, the primary focus of this chapter, that is, causes of freezing injury to red spruce (

  6. Predicting wildfire behavior in black spruce forests in Alaska.

    Treesearch

    Rodney A. Norum

    1982-01-01

    The current fire behavior system, when properly adjusted, accurately predicts forward rate of spread and flame length of wildfires in black spruce (Picea mariana (Mill.) B.S.P.) forests in Alaska. After fire behavior was observed and quantified, adjustment factors were calculated and assigned to the selected fuel models to correct the outputs to...

  7. The western spruce budworm model: structure and content.

    Treesearch

    K.A. Sheehan; W.P. Kemp; J.J. Colbert; N.L. Crookston

    1989-01-01

    The Budworm Model predicts the amounts of foliage destroyed annually by the western spruce budworm, Choristoneura occidentalis Freeman, in a forest stand. The model may be used independently, or it may be linked to the Stand Prognosis Model to simulate the dynamics of forest stands. Many processes that affect budworm population dynamics are...

  8. Foliar and soil chemistry at red spruce sites in the Monongahela National Forest

    Treesearch

    Stephanie J. Connolly

    2010-01-01

    In 2005, soil and foliar chemistry were sampled from 10 sites in the Monongahela National Forest which support red spruce. Soils were sampled from hand-dug pits, by horizon, from the O-horizon to bedrock or 152 cm, and each pit was described fully. Replicate, archived samples also were collected.

  9. Red spruce as witness tree on the Monongahela National Forest

    Treesearch

    Melissa. Thomas-Van Gundy

    2010-01-01

    A digital database of witness tree locations has been created from the earliest deeds of the area now within the Monongahela National Forest. These locations were used to describe the distribution, environmental gradients, and associated tree species of red spruce (Picea rubens) in eastern West Virginia from between 1771 and 1889.

  10. Calcium status of the forest floor in red spruce forests of the northeastern U.S. - past, present and future

    Treesearch

    Mark B. David; Gregory B. Lawrence; Walter C. Shortle; Scott W. Bailey

    1996-01-01

    Dieback and growth decline of red spruce (Picea rubens) in the eastern U.S. coincides with the period of acidic deposition, and has led to much speculation as to whether this decline is caused by decreased root-available Ca in the soil.

  11. Abundance of red spruce regeneration across spruce-hardwood ecotones at Gaudineer Knob, West Virginia

    Treesearch

    Albert E. Mayfield; Ray R. Hicks

    2010-01-01

    The abundance of red spruce (Picea rubens Sarg.) in the Central Appalachian Mountains has been drastically reduced over the past 100 to 150 years. The purpose of this study was to examine the potential for increases in the relative abundance of overstory red spruce in a Central Appalachian, high-elevation forest by measuring the abundance of red...

  12. Acidic deposition and red spruce in the central and southern Appalachians, past and present

    Treesearch

    Mary Beth. Adams

    2010-01-01

    During the 1980s, the Spruce-Fir Research Program, part of the Congressionally mandated National Atmospheric Precipitation Assessment Program (NAPAP), investigated the links between acidic deposition and decline and mortality of red spruce forests in the eastern United States. The Spruce-Fir Research Program was highly successful in advancing the state of knowledge on...

  13. The effects of a western spruce budworm outbreak on the dead wood component in relation to ownership in forests of eastern Oregon

    Treesearch

    David Azuma

    2010-01-01

    Forest Inventory and Analysis data were used to investigate the effects of a severe western spruce budworm outbreak on the dead wood component of forests in 11 counties of eastern Oregon for two time periods. The ownership and the level of damage (as assessed by aerial surveys) affected the resulting down woody material and standing dead trees. The pattern of coarse...

  14. The influences of canopy species and topographic variables on understory species diversity and composition in coniferous forests.

    PubMed

    Huo, Hong; Feng, Qi; Su, Yong-hong

    2014-01-01

    Understanding the factors that influence the distribution of understory vegetation is important for biological conservation and forest management. We compared understory species composition by multi-response permutation procedure and indicator species analysis between plots dominated by Qinghai spruce (Picea crassifolia Kom.) and Qilian juniper (Sabina przewalskii Kom.) in coniferous forests of the Qilian Mountains, northwestern China. Understory species composition differed markedly between the forest types. Many heliophilous species were significantly associated with juniper forest, while only one species was indicative of spruce forest. Using constrained ordination and the variation partitioning model, we quantitatively assessed the relative effects of two sets of explanatory variables on understory species composition. The results showed that topographic variables had higher explanatory power than did site conditions for understory plant distributions. However, a large amount of the variation in understory species composition remained unexplained. Forward selection revealed that understory species distributions were primarily affected by elevation and aspect. Juniper forest had higher species richness and α-diversity and lower β-diversity in the herb layer of the understory plant community than spruce forest, suggesting that the former may be more important in maintaining understory biodiversity and community stability in alpine coniferous forest ecosystems.

  15. Environmental changes, forest history and human impact in the southern part of Valdai Hills (European Russia) during the last 7000 years

    NASA Astrophysics Data System (ADS)

    Novenko, Elena; Tsyganov, Andery; Pisarchuk, Natalia; Kozlov, Daniil

    2017-04-01

    Understanding the long-term ecological dynamics of swampy boreal forest is essential for assessment of the possible responses and feedbacks of forest ecosystems to climate change and natural disturbance. The multi-proxy record from the Central Forest State Natural Biosphere Reserve (CFSNBR), locate on the South of Valdai Hills, provides important new data on the forest history, human impact, paludification dynamics and environmental changes in the central part of the East European Plain during the Holocene. The results of peat humification, pollen, plant macrofossil, micro charcoal and testate amoeba analyses from forest pealand show that between 7000 and 4000 cal yr BP the southern part of Valdai Hills was occupied by broad-leaved forests. Spruce occurred in forest communities as small admixture and gradually increased its abundance. After 4000 cal yr BP spruce rapidly become the main forest forming species, however broad-leaved trees took place in plant cover. Despite significant climatic fluctuation, mixed broad-leaved-spruce forests persisted in vegetation until 900 cal yr BP and then were replaced by waterlogged herbal spruce forests. The extensive Sphagnum spruce forests are recent plant communities and were formed during the last 100 years that could be explain by changes in water balance of the territory due to both climate and anthropogenic factors. According to reconstruction of Mid- and Late Holocene climate changes, warm and relatively dry period of the Holocene Thermal Maximum (7000-5500 cal yr BP) was followed by climate cooling that included several relatively cold phases at about 5000, 3500, 2000, 1200 cal yr BP and warm intervals at about 2600, 1500 and 900 cal yr BP. The distinct cooling was reconstructed between 800 and 400 cal yr BP, apparently, correlated with the Little Ice Age. Climate dynamics appeared as significant changes of environmental conditions at local ecosystem. Warming phases are indicated by high peat humification and organic matter content and relatively low peat accumulation rates. Peat deposits poses sign of several fire episodes. During cool and humid phases the rate of vertical and lateral peat growth increased, while degree of peat decomposition become lower. Dramatic changes in environmental conditions in the study area and changes in trends of ecosystem dynamics occurred during the last 400-350 year. The obtained results suggest evident climate warming, significant increase in surface wetness and increase fivefold of peat accumulation rates. During the last hundred years, the local wetness in the studied localities became considerably higher that promoted the growth of Sphagnum mosses and overall transformation of forest stands to Sphagnum spruce forests. Evidences of significant human impact on the area about 300-250 cal yr BP were detected by indicator species in pollen analysis and reconstructions of woodland coverage by BMA approach. The modern vegetation of the Reserve may develop from a plant cover with mosaic pattern that included not only the mature spruce forests but also secondary birch woodlands, meadows and agricultural lands. This study was supported by the Russian Science Foundation (Grant 16-17-10045).

  16. Can spruce beetle (Dendroctonus rufipennis Kirky) pheromone trap catches or stand conditions predict Engelmann spruce (Picea engelmannii Parry ex Engelm.) tree mortality in Colorado?

    Treesearch

    Jose F. Negron; John B. Popp

    2017-01-01

    1) Bark beetles (Coleoptera: Curculionidae: Scolytinae) can cause extensive tree mortality in forests dominated by their hosts. Among these, the spruce beetle (Dendroctonus rufipennis) is one of the most important beetles in western North America causing Engelmann spruce (Picea engelmannii) tree mortality. 2) Although pheromone traps with attractants are commonly used...

  17. Western spruce budworm as related to stand characteristics in the bitterroot national forest

    Treesearch

    Carroll B. Williams; Patrick J. Shea; Gerald S. Walton

    1971-01-01

    Relation of population density to certain stand conditions and damage indicators was analyzed in four drainages on the Bitterroot National Forest of Montana. Western spruce budworm (Choristoneura occidentalis Freeman) populations were strongly related to plot basal area, tree species, and tree crown levels, and also to current and past levels of tree defoliation....

  18. Soil Warming: Consequences for Foliar Litter Decay in a Spruce-Fir Forest in Maine, USA

    Treesearch

    Lindsey E. Rustad; Ivan J. Fernandez

    1998-01-01

    Increased rates of litter decay due to projected global warming could substantially alter the balance between C assimilation and release in forest soils, with consequent feedbacks to climate change. This study was conducted to investigate the effects of soil warming on the decomposition of red spruce (Picea rubens Sarg.) and red maple (...

  19. Proceedings of the US/FRG research symposium: effects of atmospheric pollutants on the spruce-fir forests of the Eastern United States and the Federal Republic of Germany

    Treesearch

    Gerard, tech. coord. Hertel; Gerard Hertel

    1988-01-01

    Includes 66 papers presented at the US/FRG research symposium: effects of atmospheric pollutants on the spruce-fir forests of the Eastern United States and the Federal Republic of Germany, which was held October 19-23, 1987, in Burlington, Vermont.

  20. Some harvest options and their consequences for the aspen, birch, and associated forest types of the Lake States.

    Treesearch

    L.F Ohmann; H.O. Batzer; R.R. Buech; D.C. Lothner; D. A. Perala; A.L. Schipper; E.S. Verry

    1978-01-01

    Describes some harvest options and their consequences in terms of timber investment return, water yield and quality, wildlife, visual quality, and disease and insect impact for the aspen, white birch, red pine, white pine, jack pine, black spruce, spruce-fir, and white-cedar forest types of the Lake States.

  1. Location, evolution and importance of Cephalcia spp. (Hym: Pamphiliidae) populations in Polish Carpathian Mountains

    Treesearch

    Marcin Jachym

    2003-01-01

    The web-spinning sawflies (Cephalcia Panz.) are members of the Symphyta that are of economic significance, and which constitutes an integral part of the spruce forest environment. Spruce, which is the dominant component of Western Carpathian forest stands, is the only known host plant for all the species of Cephalcia...

  2. Stand dynamics of relict red spruce in the Alarka Creek headwaters, North Carolina

    Treesearch

    Beverly Collins; Thomas M. Schuler; W. Mark Ford; Danielle. Hawkins

    2010-01-01

    Disjunct red spruce (Picea rubens Sarg.) forests in the southern Appalachians can serve as models for understanding past and future impacts of climate change and other perturbations for larger areas of high-elevation forests throughout the Appalachians. We conducted a vegetation and dendrochronological survey to determine the age, size class, and...

  3. Below-ground effects of enhanced tropospheric ozone and drought in a beech/spruce forest (Fagus sylvatica L. / Picea abies [L.] Karst)

    EPA Science Inventory

    The effects of experimentally elevated O3 on soil respiration rates, standing fine-root biomass, fine-root production and δ13C signature of newly produced fine roots were investigated in an adult European beech/Norway spruce forest in Germany during two subsequent years with cont...

  4. Flower production on clonal orchards at Oconto River Seed Orchard in Wisconsin

    Treesearch

    J.G. Murphy; R.G. Miller

    1977-01-01

    The Eastern Region, USDA Forest Service has been establishing and managing seed orchards to produce improved seed for the National Forests in the Lake States since 1969. This paper presents a review of the female flower production for the past 4 years in the white pine, white spruce, and black spruce clonal seed orchards.

  5. Negative impacts of high temperatures on growth of black spruce forests intensify with the anticipated climate warming.

    PubMed

    Girardin, Martin P; Hogg, Edward H; Bernier, Pierre Y; Kurz, Werner A; Guo, Xiao Jing; Cyr, Guillaume

    2016-02-01

    An increasing number of studies conclude that water limitations and heat stress may hinder the capacity of black spruce (Picea mariana (Mill.) B.S.P.) trees, a dominant species of Canada's boreal forests, to grow and assimilate atmospheric carbon. However, there is currently no scientific consensus on the future of these forests over the next century in the context of widespread climate warming. The large spatial extent of black spruce forests across the Canadian boreal forest and associated variability in climate, demography, and site conditions pose challenges for projecting future climate change responses. Here we provide an evaluation of the impacts of climate warming and drying, as well as increasing [CO2 ], on the aboveground productivity of black spruce forests across Canada south of 60°N for the period 1971 to 2100. We use a new extensive network of tree-ring data obtained from Canada's National Forest Inventory, spatially explicit simulations of net primary productivity (NPP) and its drivers, and multivariate statistical modeling. We found that soil water availability is a significant driver of black spruce interannual variability in productivity across broad areas of the western to eastern Canadian boreal forest. Interannual variability in productivity was also found to be driven by autotrophic respiration in the warmest regions. In most regions, the impacts of soil water availability and respiration on interannual variability in productivity occurred during the phase of carbohydrate accumulation the year preceding tree-ring formation. Results from projections suggest an increase in the importance of soil water availability and respiration as limiting factors on NPP over the next century due to warming, but this response may vary to the extent that other factors such as carbon dioxide fertilization, and respiration acclimation to high temperature, contribute to dampening these limitations. © 2015 Her Majesty the Queen in Right of Canada. Reproduced with the permission of the Minister of Natural Resources Canada.

  6. Disruption of calcium nutrition at Hubbard Brook Experimental Forest (New Hampshire) alters the health and productivity of red spruce and sugar maple trees and provides lessons pertinent to other sites and regions

    Treesearch

    Paul G. Schaberg; Gary J. Hawley

    2010-01-01

    Pollution-induced acidification and other anthropogenic factors are leaching calcium (Ca) and mobilizing aluminum (Al) in many forest soils. Because Ca is an essential nutrient and Al is a potential toxin, resulting depletions of Ca and increases in available Al may significantly alter the health and productivity of forest trees. Controlled experiments on red spruce (...

  7. Experimental soil warming effects on CO2 and CH4 flux from a low elevation spruce-fir forest soil in Maine, USA

    Treesearch

    Lindsey E. Rustad; Ivan J. Fernandez

    1998-01-01

    The effect of soil warming on CO2 and CH4 flux from a spruce-fir forest soil was evaluated at the Howland Integrated Forest Study site in Maine, USA from 1993 to 1995. Elevated soil temperatures (~5 °C) were maintained during the snow-free season (May-November) in replicated 15 × 15-m plots using electric cables buried 1-2...

  8. Root mass, net primary production and turnover in aspen, jack pine and black spruce forests in Saskatchewan and Manitoba, Canada.

    PubMed

    Steele, Sarah J.; Gower, Stith T.; Vogel, Jason G.; Norman, John M.

    1997-01-01

    Root biomass, net primary production and turnover were studied in aspen, jack pine and black spruce forests in two contrasting climates. The climate of the Southern Study Area (SSA) near Prince Albert, Saskatchewan is warmer and drier in the summer and milder in the winter than the Northern Study Area (NSA) near Thompson, Manitoba, Canada. Ingrowth soil cores and minirhizotrons were used to quantify fine root net primary production (NPPFR). Average daily fine root growth (m m(-2) day(-1)) was positively correlated with soil temperature at 10-cm depth (r(2) = 0.83-0.93) for all three species, with black spruce showing the strongest temperature effect. At both study areas, fine root biomass (measured from soil cores) and fine root length (measured from minirhizotrons) were less for jack pine than for the other two species. Except for the aspen stands, estimates of NPPFR from minirhizotrons were significantly greater than estimates from ingrowth cores. The core method underestimated NPPFR because it does not account for simultaneous fine root growth and mortality. Minirhizotron NPPFR estimates ranged from 59 g m(-2) year(-1) for aspen stands at SSA to 235 g m(-2) year(-1) for black spruce at NSA. The ratio of NPPFR to total detritus production (aboveground litterfall + NPPFR) was greater for evergreen forests than for deciduous forests, suggesting that carbon allocation patterns differ between boreal evergreen and deciduous forests. In all stands, NPPFR consistently exceeded annual fine root turnover and the differences were larger for stands in the NSA than for stands in the SSA, whereas the difference between study areas was only significant for black spruce. The imbalance between NPPFR and fine root turnover is sufficient to explain the net accumulation of carbon in boreal forest soils.

  9. Spruce beetle (Coleoptera: Scolytidae) response to traps baited with selected semiochemicals in Utah.

    Treesearch

    Darrell W. Ross; Gary E. Daterman; A. Steven Munson

    2005-01-01

    Spruce beetle, Dendroctonus rufipennis (Kirby), populations periodically reach outbreak densities throughout the range of spruce, Picea spp., in western North America. During outbreaks it may kill thousands to millions of trees over vast areas, dramatically altering forest structure, composition, and ecological processes, thus impacting a variety...

  10. Oldest known Engelmann spruce

    Treesearch

    Peter M. Brown; Wayne D. Shepperd; Christopher C. Brown; Stephen A. Mata; Douglas L. McClain

    1995-01-01

    Age structure in a stand of very old-age Engelmann spruce is described. The site is at 3,505 m near treeline in the Fraser Experimental Forest in central Colorado. The site contains the oldest Engelmann spruce trees yet reported in the literature; the oldest tree is at least 852 years of age.

  11. The Kenai experience: communities and forest health.

    Treesearch

    Valerie. Rapp

    2005-01-01

    Over the last 15 years, spruce bark beetles have killed huge numbers of spruce trees, the dominant conifer across south-central Alaska. From 80 to 90 percent of the trees are dead in large areas on the Kenai Peninsula. The consequences of the spruce bark beetle outbreak will continue for years.

  12. Ecosystem disturbances in Central European spruce forests: a multi-proxy integration of dendroecology and sedimentary records

    NASA Astrophysics Data System (ADS)

    Clear, Jennifer; Chiverrell, Richard; Kunes, Petr; Svoboda, Miroslav; Boyle, John

    2016-04-01

    Disturbance dynamics in forest ecosystems shows signs of perturbation in the light of changing climate regimes with the frequency and intensity of events (e.g. pathogens in North America and Central Europe) amplified, becoming more frequent and severe. The montane Norway spruce (Picea abies) dominated forests of Central Europe are a niche habitat and environment; situated outside their natural boreal distribution (e.g. Fenno-Scandinavia). These communities are at or near their ecological limits and are vulnerable to both short term disturbances (e.g. fire, windstorm and pathogens) and longer-term environmental change (e.g. climate induced stress and changing disturbance patterns). Researches have linked negative impacts on spruce forest with both wind disturbance (wind-throw) and outbreaks of spruce bark beetle (Ips typographus), and there is growing evidence for co-association with wind damage enhancing pathogenic outbreaks. Examples include: in the Bohemian Forest (Czech Republic) the mid-1990s spruce bark beetle outbreak and the 2007 windstorm and subsequent bark beetle outbreak. In the High Tatra Mountains (Slovakia) there is a further co-association of forest disturbance with windstorms (2004 and 2014) and an ongoing bark beetle outbreak. The scale and severity of these recent outbreaks of spruce bark beetle are unprecedented in the historical forest records. Here, findings from ongoing research developing and integrating data from dendroecological, sedimentary palaeoecological and geochemical time series to develop a longer-term perspective on forest dynamics in these regions. Tree-ring series from plots or forest stands (>500) are used alongside lake (5) and forest hollow (3) sediments from the Czech and Slovak Republics to explore the local, regional and biogeographical scale of forest disturbances. Dendroecological data showing tree-ring gap recruitment and post-suppression growth release highlight frequent disturbance events focused on tree or forest stand spatial scales, but are patchy in terms of reoccurrence. However they highlight levels of disturbance in the late 19th Century. Sediment records from lakes and forest hollows record variable pollen influx (beetle host / non-host ratios) and a stratigraphy that includes mineral in-wash events. μXRF scanning of lakes in the region with varying catchments and catchment-to-lake area ratios show spikes in K, Zr, Ti concentrations reflecting frequent erosive episodes throughout the Holocene. Linking across the temporal scales inherent in dendroecological (0 to 250 years) and sedimentary (0 to 11,500 years) is enhancing our understanding of disturbance dynamics. The identified recent and ongoing forest disturbances coupled with well-evidenced events in the 19th century highlight the need for the longer sedimentary perspective to assess whether contemporary climate warming has and continues to stretch the resilience of these fragile ecosystems. Our data are informative to the ongoing land-management conflict between active forest management (harvesting valuable timber and salvage logging) and forest conservation agenda encouraging forest dynamics and disturbance recovery.

  13. Evaporation and transpiration from forests in Central Europe - relevance of patch-level studies for spatial scaling

    NASA Astrophysics Data System (ADS)

    Köstner, B.

    Spatial scaling from patch to the landscape level requires knowledge on the effects of vegetation structure on maximum surface conductances and evaporation rates. The following paper summarizes results on atmospheric, edaphic, and structural controls on forest evaporation and transpiration observed in stands of Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and European beech (Fagus sylvatica). Forest canopy transpiration (Ec) was determined by tree sapflow measurements scaled to the stand level. Estimates of understory transpiration and forest floor evaporation were derived from lysimeter and chamber measurements. Strong reduction of Ec due to soil drought was only observed at a Scots pine stand when soil water content dropped below 16% v/v. Although relative responses of Ec on atmospheric conditions were similar, daily maximum rates of could differ more than 100% between forest patches of different structure (1.5-3.0mmd-1 and 2.6-6.4mmd-1 for spruce and beech, respectively). A significant decrease of Ecmax per leaf area index with increasing stand age was found for monocultures of Norway spruce, whereas no pronounced changes in were observed for beech stands. It is concluded that structural effects on Ecmax can be specified and must be considered for spatial scaling from forest stands to landscapes. Hereby, in conjunction with LAI, age-related structural parameters are important for Norway spruce stands. Although compensating effects of tree canopy layers and understory on total evaporation of forests were observed, more information is needed to quantify structure-function relationships in forests of heterogenous structure.

  14. An analytical method to assess spruce beetle impacts on white spruce resources, Kenai Peninsula, Alaska.

    Treesearch

    Willem W.S. van Hees

    1992-01-01

    Forest inventory data collected in 1987 fTom sample plots established on the Kenai Peninsula were analyzed to provide point-in-time estimates of the trend and current status of a spruce beetle infestation. Ground plots were categorized by stage of infestation. Estimates of numbers of live and dead white spruce trees, cubic-foot volume in those trees, and areal extent...

  15. Coarse woody debris in a Southern Appalachian spruce-fir forest of the Great Smoky Mountains National Park

    Treesearch

    Anita K. Rose; N.S. Nicholas

    2008-01-01

    Spruce-fir forests in the southern Appalachian Mountains receive high atmospheric nitrogen inputs and have high nitrate levels in soil solution and streamwater. High levels of excess nitrogen have been associated with reduced tree vigor. Additionally, the balsam woolly adelgid (Adelges piceae Ratz.) has killed the majority of endemic Fraser fir [

  16. Spatiotemporal dynamics of recent mountain pine beetle and western spruce budworm outbreaks across the Pacific Northwest Region, USA

    Treesearch

    Garrett W. Meigs; Robert E. Kennedy; Andrew N. Gray; Matthew J. Gregory

    2015-01-01

    Across the western US, the two most prevalent native forest insect pests are mountain pine beetle (MPB; Dendroctonus ponderosae; a bark beetle) and western spruce budworm (WSB; Choristoneura freemani; a defoliator). MPB outbreaks have received more forest management attention than WSB outbreaks, but studies to date have not compared their cumulative mortality impacts...

  17. Relationships between prefire composition, fire impact, and postfire legacies in the boreal forest of Eastern Canada

    Treesearch

    Alain Leduc; Yves Bergeron; Sylvie Gauthier

    2007-01-01

    Canadian mixedwood forests have a high compositional and structural diversity. It includes both hardwood (aspen, balsam poplar, and white birch) and softwood (balsam fir, white spruce, black spruce, larch, and white cedar) species that can form pure stands or mixed stands. This heterogeneity results in a variety of vertical structural strata that can potentially...

  18. The historical role of Ips hauseri (Coleoptera: Curculionidae) in the spruce forest of Ile-Alatausky and Medeo National Parks

    Treesearch

    N. Mukhamadiev; A. Lynch; C. O' Connor; A. Sagitov; N. Ashikbaev; I. Panyushkina

    2014-01-01

    On 17 May and 27 June 2011 severe cyclonic storms damaged several hundred hectares of spruce forest (Picea schrenkiana) in the Tian Shan Mountains. Bark beetle populations increased rapidly in dead and damaged trees, particularly Ips hauseri, I. typographus, I. sexdentatus, and Piiyogenesperfossus (all Coleoptera: Curculionidae), and there is concern about the...

  19. Life-history traits maintain the genomic integrity of sympatric species of the spruce budworm (Choristoneura fumiferana) group on an isolated forest island

    Treesearch

    Lisa M. Lumley; Felix A.H. Sperling

    2011-01-01

    Identification of widespread species collected from islands can be challenging due to the potential for local ecological and phenotypic divergence in isolated populations. We sought to determine how many species of the spruce budworm (Choristoneura fumiferana) complex reside in Cypress Hills, an isolated remnant coniferous forest in western Canada....

  20. Braconid (Hymenoptera, Braconidae) parasitoids of bark beetles in upland spruce stands of the Czech Republic

    Treesearch

    Aural Lozan; Jiri Zeleny

    2003-01-01

    Several species of bark beetles occur frequently in the upland spruce forests of the Czech Republic; some of them are serious pests that may cause vast destruction of forest stands. In the last decade, a complex of several species from the genera Ips, Pityogenes and Polygraphus contributed to large-scale devastation of thousand...

  1. Red spruce stand dynamics, simulations, and restoration opportunities in the central Appalachians

    Treesearch

    James S. Rentch; Thomas M. Schuler; W. Mark Ford; Gergory J. Nowacki

    2007-01-01

    Red spruce (Picea rubens)-dominated forests occupied as much as 600,000 ha in West Virginia prior to exploitive logging era of the late nineteenth and early twentieth centuries. Subsequently, much of this forest type was converted to northern hardwoods. As an important habitat type for a number of rare or sensitive species, only about 12,000 ha of...

  2. Seedling distribution on a spruce-hemlock clearcut.

    Treesearch

    Carl M. Berntsen

    1955-01-01

    A better job of regeneration on cutover areas can be done if foresters know what areas are difficult to regenerate and what sort of practices are best for the difficult areas. A study recently completed at Cascade Head Experimental Forest has supplied that sort of information for a typical spruce-hemlock clearcut. Nearly a fifth of the area was still unstocked 6 years...

  3. Secondary succession following logging in the Sitka sprucewestern hemlock forests of southeast Alaska: Implications for wildlife management.

    Treesearch

    Paul B. Alaback

    1984-01-01

    Preliminary information on general landscape patterns in southeast Alaska suggests that two major, compositionally distinct vegetation zones can be defined for the closed-forest type: western hemlock-Sitka spruce/Alaska huckleberry/bunchberry on the uplands, and Sitka spruce/devils club-salmonberry on alluvial flats and terraces.Recent clearcuts (0 to 30...

  4. Postfire seed rain of black spruce, a semiserotinous conifer, in forests of interior Alaska

    Treesearch

    Jill Johnstone; Leslie Boby; Emily Tissier; Michelle Mack; Dave Verbyla; Xanthe. Walker

    2009-01-01

    The availability of viable seed can act as an important constraint on plant regeneration following disturbance. This study presents data on seed quantity and quality for black spruce (Picea mariana (Mill.) B.S.P.), a semiserotinous conifer that dominates large areas of North American boreal forest. We sampled seed rain and viability for 2 years...

  5. Climate driven changes in Engelmann spruce stands at timberline in the La Sal Mountains

    Treesearch

    James F. Fowler; Steven Overby; Barb Smith

    2012-01-01

    Due to global warming spruce-fir forest and associated vegetation may experience elevational displacement and altered species composition at the timberline-treeline ecotone. These forests and their component species are predicted to migrate upslope and thus landscape features such as timberline and treeline may move upslope as well. Prior to this study, baseline data...

  6. Interglacial Extension of the Boreal Forest Limit in the Noatak Valley, Northwest Alaska: Evidence from an Exhumed River-Cut Bluff and Debris Apron

    USGS Publications Warehouse

    Edwards, M.E.; Hamilton, T.D.; Elias, S.A.; Bigelow, N.H.; Krumhardt, A.P.

    2003-01-01

    Numerous exposures of Pleistocene sediments occur in the Noatak basin, which extends for 130 km along the Noatak River in northwestern Alaska. Nk-37, an extensive bluff exposure near the west end of the basin, contains a record of at least three glacial advances separated by interglacial and interstadial deposits. An ancient river-cut bluff and associated debris apron is exposed in profile through the central part of Nk-37. The debris apron contains a rich biotic record and represents part of an interglaciation that is probably assignable to marine-isotope stage 5. Pollen spectra from the lower part of the debris apron closely resemble modern samples taken from the Noatak floodplain in spruce gallery forest, and macrofossils of spruce are also present at this level. Fossil bark beetles and carpenter ants occur higher in the debris apron. Mutual Climatic Range (MCR) estimates from the fossil beetles suggest temperatures similar to or warmer than today. Together, these fossils indicate the presence of an interglacial spruce forest in the western part of the Noatak Basin, which lies about 80 km upstream of the modern limit of spruce forest.

  7. Multi-Cohort Stand Structural Classification: Ground- and LiDAR-based Approaches for Boreal Mixedwood and Black Spruce Forest Types of Northeastern Ontario

    NASA Astrophysics Data System (ADS)

    Kuttner, Benjamin George

    Natural fire return intervals are relatively long in eastern Canadian boreal forests and often allow for the development of stands with multiple, successive cohorts of trees. Multi-cohort forest management (MCM) provides a strategy to maintain such multi-cohort stands that focuses on three broad phases of increasingly complex, post-fire stand development, termed "cohorts", and recommends different silvicultural approaches be applied to emulate different cohort types. Previous research on structural cohort typing has relied upon primarily subjective classification methods; in this thesis, I develop more comprehensive and objective methods for three common boreal mixedwood and black spruce forest types in northeastern Ontario. Additionally, I examine relationships between cohort types and stand age, productivity, and disturbance history and the utility of airborne LiDAR to retrieve ground-based classifications and to extend structural cohort typing from plot- to stand-levels. In both mixedwood and black spruce forest types, stand age and age-related deadwood features varied systematically with cohort classes in support of an age-based interpretation of increasing cohort complexity. However, correlations of stand age with cohort classes were surprisingly weak. Differences in site productivity had a significant effect on the accrual of increasingly complex multi-cohort stand structure in both forest types, especially in black spruce stands. The effects of past harvesting in predictive models of class membership were only significant when considered in isolation of age. As an age-emulation strategy, the three cohort model appeared to be poorly suited to black spruce forests where the accrual of structural complexity appeared to be more a function of site productivity than age. Airborne LiDAR data appear to be particularly useful in recovering plot-based cohort types and extending them to the stand-level. The main gradients of structural variability detected using LiDAR were similar between boreal mixedwood and black spruce forest types; the best LiDAR-based models of cohort type relied upon combinations of tree size, size heterogeneity, and tree density related variables. The methods described here to measure, classify, and predict cohort-related structural complexity assist in translating the conceptual three cohort model to a more precise, measurement-based management system. In addition, the approaches presented here to measure and classify stand structural complexity promise to significantly enhance the detail of structural information in operational forest inventories in support of a wide array of forest management and conservation applications.

  8. Climate-growth relationships along a black spruce toposequence in Interior Alaska

    Treesearch

    Jane M. Wolken; Daniel H. Mann; Thomas A. Grant; Andrea H. Lloyd; T. Scott Rupp; Teresa N. Hollingsworth

    2016-01-01

    Despite its wide geographic distribution and important role in boreal forest fire regimes, little is known about the climate-growth relationships of black spruce (Picea mariana [Mill.] B.S.P.). We used site- and tree-level analyses to evaluate the radial growth responses to climate of black spruce growing...

  9. Remote detection of forest damage

    NASA Technical Reports Server (NTRS)

    Rock, B. N.; Vogelmann, J. E.; Vogelmann, A. F.; Hoshizaki, T.; Williams, D. L.

    1986-01-01

    The use of remote sensing to discriminate, measure, and map forest damage is evaluated. TM spectal coverage, a helicopter-mounted radiometer, and ground-based surveys were utilized to examine the responses of the spruces and firs of Camels Hump Mountain, Vermont to stresses, such as pollution and trace metals. The basic spectral properties of vegetation are described. Forest damage at the site was estimated as 11.8-76.0 percent for the spruces and 19-43.8 percent for the balsam firs. Shifts in the spectra of the conifers in particular in the near IR region are analyzed, and variations in the mesophyll cell anatomy and pigment content of the spruces and firs are investigated. The relations between canopy moisture and damage is studied. The TM data are compared to aircraft data and found to be well correlated.

  10. Structure and dynamics in a virgin northern hardwood-spruce-fir forest--the Bowl, New Hampshire

    Treesearch

    Stanley R. Gemborys

    1996-01-01

    A phytosociological study was conducted in a virgin northern hardwood- spruce-fir forest in the Bowl in the White Mountains of New Hampshire. There is no evidence of fire or human disturbance but hurricane winds were significant in the past. Bray and Curtis ordination was used to develop an XY vegetational mosaic. Differentiating species were Picea rubens and Acer...

  11. Relation of heart rots to mortality of red spruce in the Green Mountain National Forest

    Treesearch

    Paul V. Mook; Harold G. Eno

    1956-01-01

    Several years ago, old-growth red spruce at high elevations in the Green Mountain National Forest were observed to be dying. Entomologists and pathologists who examined the affected area found no insect or fungus that was obviously causing the deaths. However, many of the dead and dying trees were butt-rotted by the fungus Polyporus borealis. Though it seemed unlikely...

  12. Field performance in southeast Alaska of sitka spruce seedlings produced at two nurseries.

    Treesearch

    John C. Zasada; Peyton W. Owston; Dennis Murphy

    1990-01-01

    A study of nursery stock performance was conducted on four sites in the Tongass National Forest in southeastern Alaska: two sites at Fire Cove (Ketchikan Ranger District [R.D.]) and one each at Anita Bay (Wrangell R.D.) and Eight Fathom (Hoonah R.D.). Containerized Sitka spruce seedlings used in the study were grown at USDA Forest Service nurseries in Petersburg,...

  13. Environmental equity and the conservation of unique ecosystems: an analysis of the distribution of benefits for protecting Southern Appalachian spruce-fir forests

    Treesearch

    Joseph E. Aldy; Randall A. Kramer; Thomas P. Holmes

    1999-01-01

    Some critics in the environmental equity literature argue that low-income populations disproportionately have environmental risks, while the wealthy and better educated gain disproportionately from protecting unique ecosystems. The authors test this hypothesis in an analysis of the decline of Southern Appalachian spruce-fir forests. They calculate willingness-to-pay...

  14. Effects of forest disturbance and soil depth on digestible energy for moose and white-tailed deer

    Treesearch

    Hewlette S. Crawford; R. A. Lautenschlager; Martin R. Stokes; Timothy L. Stone

    1993-01-01

    Spruce budworm defoliation, clearcutting for salvage, and prescribed burning of clearcut areas on deep and shallow soils influenced deer and moose foraging in eastern Maine spruce-fir forests from 1980 to 1984. Plant standing crop biomass, seasonal plant selection by tractable moose and white-tailed deer, and digestible energy for deer and moose were determined for...

  15. FIBER handbook: a growth model for spruce-fir and northern hardwood types

    Treesearch

    Dale S. Solomon; Richard A. Hosmer; Homer T., Jr. Hayslett; Homer T. Hayslett

    1987-01-01

    A matrix model, FIBER, has been developed to provide the forest manager with a means of simulating the management and growth of forest stands in the Northeast. Instructional material is presented for the management of even-aged and multi-aged spruce-fir, mixedwood, and northern hardwood stands. FIBER allows the user to simulate a range of silvicultural treatments for a...

  16. Changes after partial cutting of a spruce-fir stand in Maine

    Treesearch

    Arthur C. Hart

    1956-01-01

    In 1945 a partial-cutting experiment in spruce-fir silviculture was begun by the Penobscot Research Center of the Northeastern Forest Experiment Station. The Eastern Pulp Wood Company of Calais, Maine, made available for the study a tract of forest land, in Dyer Township, Washington County, Maine. This 20.6-acre tract is part of a large area that had been burned over...

  17. Genetic diversity, genetic structure, and mating system of brewer spruce (Pinaceae), a relict of the acto-tertiary forest

    Treesearch

    F. Thomas Ledig; Paul D. Hodgskiss; David R. Johnson

    2005-01-01

    Brewer spruce (Picea breweriana), a relict of the widespread Arcto-Tertiary forests, is now restricted to a highly fragmented range in the Klamath Region of California and Oregon. Expected heterozygosity for 26 isozyme loci, averaged over 10 populations, was 0.121. More notable than the relatively high level of diversity when compared to other woody...

  18. Calcium fertilization increases the concentration of calcium in sapwood and calcium oxalate in foliage of red spruce

    Treesearch

    Kevin T. Smith; Walter C. Shortle; Jon H. Connolly; Rakesh Minocha; Jody Jellison

    2009-01-01

    Calcium cycling plays a key role in the health and productivity of red spruce forests in the northeastern US. A portion of the flowpath of calcium within forests includes translocation as Ca2+ in sapwood and accumulation as crystals of calcium oxalate in foliage. Concentrations of Ca in these tree tissues have been used as markers of...

  19. Differences in ecosystem carbon distribution and nutrient cycling linked to forest tree species composition in a mid-successional boreal forest

    USGS Publications Warehouse

    Melvin, April M.; Mack, Michelle C.; Johnstone, Jill F.; McGuire, A. David; Genet, Helene; Schuur, Edward A.G.

    2015-01-01

    In the boreal forest of Alaska, increased fire severity associated with climate change is expanding deciduous forest cover in areas previously dominated by black spruce (Picea mariana). Needle-leaf conifer and broad-leaf deciduous species are commonly associated with differences in tree growth, carbon (C) and nutrient cycling, and C accumulation in soils. Although this suggests that changes in tree species composition in Alaska could impact C and nutrient pools and fluxes, few studies have measured these linkages. We quantified C, nitrogen, phosphorus, and base cation pools and fluxes in three stands of black spruce and Alaska paper birch (Betula neoalaskana) that established following a single fire event in 1958. Paper birch consistently displayed characteristics of more rapid C and nutrient cycling, including greater aboveground net primary productivity, higher live foliage and litter nutrient concentrations, and larger ammonium and nitrate pools in the soil organic layer (SOL). Ecosystem C stocks (aboveground + SOL + 0–10 cm mineral soil) were similar for the two species; however, in black spruce, 78% of measured C was found in soil pools, primarily in the SOL, whereas aboveground biomass dominated ecosystem C pools in birch forest. Radiocarbon analysis indicated that approximately one-quarter of the black spruce SOL C accumulated prior to the 1958 fire, whereas no pre-fire C was observed in birch soils. Our findings suggest that tree species exert a strong influence over C and nutrient cycling in boreal forest and forest compositional shifts may have long-term implications for ecosystem C and nutrient dynamics.

  20. Latitudinal shifts in spruce budworm (Lepidoptera: Tortricidae) outbreaks and spruce-fir forest distrbutions with climate change

    Treesearch

    D.W. Williams; Andrew Liebhold

    1997-01-01

    Changes in global temperatures over the next century resulting from the greenhouse effect may have profound effects on the distribution and abundance of insect populations. One general hypothesis is the poleward shift of species distributions. We investigated potential range shifts for the spruce budworm, Choristoneura fumiferana, in the...

  1. A density management diagram for Norway spruce in the temperate Europe montane region

    Treesearch

    Giorgio Vacchiano; R. Justin DeRose; John D. Shaw; Miroslav Svoboda; Renzo Motta

    2013-01-01

    Norway spruce is one of the most important conifer tree species in Europe, paramount for timber provision, habitat, recreation, and protection of mountain roads and settlements from natural hazards. Although natural Norway spruce forests exhibit diverse structures, even-aged stands can arise after disturbance or as the result of common silvicultural practice, including...

  2. Factors influencing northern spruce engraver colonization of white spruce slash in interior Alaska

    Treesearch

    Christopher J. Fettig; Roger E. Burnside; Chistopher J. Hayes; James J. Kruse; Nicholas J. Lisuzzo; Stephen R. McKelvey; Sylvia R. Mori; Stephen K. Nickel; Mark E. Schultz

    2013-01-01

    In interior Alaska, increased use of mechanical fuel reduction treatments, increased interests in the use of wood energy systems as alternatives to fossil fuels, and elevated populations of northern spruce engraver, Ips perturbatus (Eichhoff), have raised concerns regarding the impact of this bark beetle to forest resources. We conducted a large-...

  3. Acidic deposition, cation mobilization, and biochemical indicators of stress in healthy red spruce

    Treesearch

    Walter C. Shortle; Kevin T. Smith; Rakesh Minocha; Gregory B. Lawrence; Mark B. David

    1997-01-01

    Dendrochemical and biochemical markers link stress in apparently healthy red spruce trees (Picea rubens) to acidic deposition. Acidic deposition to spruce forests of the northeastern USA increased sharply during the 1960s. Previous reports related visible damage of trees at high elevations to root and soil processes. In this report, dendrochemical...

  4. Decay of subalpine fir in Colorado

    Treesearch

    Thomas E. Hinds; Frank G. Hawksworth; Ross W. Davidson

    1960-01-01

    Spruce-fir is one of the major forest types in the central Rocky Mountains. Engelmann spruce, Picea engelmanni Parry, is usually the predominant species with subalpine fir, Abies lasiocarpa (Hook. ) Nutt., making up one-fourth or less of the total volume. Lodgepole pine, Pinus contorta Dougl. ex Loud., is frequently present at the lower elevations of the spruce-fir...

  5. The isolated red spruce communities of Virginia and West Virginia

    Treesearch

    Harold S. Adams; Steven Stephenson; Adam W. Rollins; Mary Beth Adams

    2010-01-01

    Quantitative data on the composition and structure of coniferous forests containing red spruce in the mountains of central and southwestern Virginia and eastern central West Virginia, based on sampling carried out in 67 stands during the 1982 to 1984 field seasons, are provided. The average importance value ([relative basal area + relative density/2]) of red spruce was...

  6. Patch occupancy and dispersal of spruce grouse on the edge of its range in Maine

    USGS Publications Warehouse

    Whitcomb, S.A.; Servello, F.A.; O'Connell, A.F.

    1996-01-01

    We surveyed 18 habitat patches (black spruce (Picea marinana) - tamarack (Larix larcina) wetlands) for spruce grouse (Dendragapus canadensis canadensis) on Mount Desert Island, Maine, during April-May in 1992 and 1993 to determine patch occupancy relative to patch area. We also equipped nine juvenile grouse with radio transmitters to determine movement and habitat use outside of patches during autumn dispersal. The 2 large patches (77 and 269 ha), 5 of 6 medium-sized (11-26 ha) patches, and 1 of 10 small (4-8 ha) patches were occupied. Spruce grouse occupied smaller habitat patches than previously reported, and occupied patches were closer (P < 0.05) to the nearest occupied patch (x = 1.2 km) than were unoccupied patches (x = 2.5 km). Eight of nine juvenile grouse left their natal habitat patch during autumn dispersal, and net dispersal distance (x = 2.3 km) was greater than that reported for grouse in areas with more contiguous habitat. Dispersing juveniles used all major forest types and 33 % of relocations were in deciduous forest. Thus, deciduous forest was not an absolute dispersal barrier.

  7. Field tests with a highly concentrated Bacillus thuringiensis formula against spruce budworm, Choristoneura fumiferana (Clem.) (Lepidoptera: tortricidae)

    Treesearch

    W. A. Smirnoff

    1985-01-01

    Field tests were conducted in 1980, 1981, and 1982 with a new Bacillus thuringiensis formula called Futura. Tests were conducted with a Grumman AgCat aircraft on 40 ha forest blocks and with a DC-4G aircraft on larger forested areas. Futura which is able to disperse the required 20 x 109 I.U./ha for spruce budworm control in 2....

  8. Aluminum mobilization and calcium depletion in the forest floor of red spruce forests in the northeastern United States

    Treesearch

    Gregory B. Lawrence; Mark B. David; Walter C. Shortle

    1996-01-01

    Mechanisms of Ca depletion were investigated as part of a regional study of relations among acidic deposition, soil chemistry and red spruce decline. Comparison with results from studies in the Adirondack Mountains of New York and the White Mountains of New Hampshire indicates that current acid-extractable Ca concentrations in the Oa horizon are less than one-half the...

  9. Recovery of carbon pools a decade after wildfire in black spruce forests of interior Alaska: effects of soil texture and landscape position

    Treesearch

    Gregory P. Houle; Evan S. Kane; Eric S. Kasischke; Carolyn M. Gibson; Merritt R. Turetsky

    2017-01-01

    We measured organic-layer (OL) recovery and carbon stocks in dead woody debris a decade after wildfire in black spruce (Picea mariana (Mill.) B.S.P.) forests of interior Alaska. Previous study at these research plots has shown the strong role that landscape position plays in governing the proportion of OL consumed during fire and revegetation after...

  10. Stakeholders' relationships with the USDA Forest Service at the Spruce Knob-Seneca Rocks National Recreation Area, West Virginia

    Treesearch

    Katherine A. Thompson; Chad D. Pierskalla; Steven W. Selin

    2007-01-01

    The Spruce Knob-Seneca Rocks National Recreation Area (NRA) is developing a collaborative management plan. To develop a public involvement strategy, it is necessary to assess the social conditions in the area. The purpose of this study was to determine the relationship local stakeholders in the NRA have with the USDA Forest Service (USFS) with regard to the...

  11. Assessment of calcium status in soils of red spruce forests in the northeastern United States

    Treesearch

    Gergory B. Lawrence; Mark B. David; Scott W. Bailey; Walter C. Shortle

    1997-01-01

    Long term changes in concentrations of available Ca in soils of red spruce forests have been documented, but remaining questions about the magnitude and regional extent of these changes have precluded an assessment of the current and future status of soil Ca. To address this problem, soil samples were collected in 1992-93 from 12 sites in New York, Vermont, New...

  12. Evaluation of the composite burn index for assessing fire severity in Alaskan black spruce forests

    Treesearch

    Eric S. Kasischke; Merritt R. Turetsky; Roger D. Ottmar; Nancy H.F. French; Elizabeth E. Hoy; Evan S. Kane

    2008-01-01

    We evaluated the utility of the composite burn index (CBI) for estimating fire severity in Alaskan black spruce forests by comparing data from 81 plots located in 2004 and 2005 fire events. We collected data to estimate the CBI and quantify crown damage, percentage of trees standing after the fire, depth of the organic layer remaining after the fire, depth of burning...

  13. Climate-induced mortality of spruce stands in Belarus

    NASA Astrophysics Data System (ADS)

    Kharuk, Viacheslav I.; Im, Sergei T.; Dvinskaya, Maria L.; Golukov, Alexei S.; Ranson, Kenneth J.

    2015-12-01

    The aim of this work is an analysis of the causes of spruce (Picea abies L.) decline and mortality in Belarus. The analysis was based on forest inventory and Landsat satellite (land cover classification, climate variables (air temperature, precipitation, evaporation, vapor pressure deficit, SPEI drought index)), and GRACE-derived soil moisture estimation (equivalent of water thickness anomalies, EWTA). We found a difference in spatial patterns between dead stands and all stands (i.e., before mortality). Dead stands were located preferentially on relief features with higher water stress risk (i.e., higher elevations, steeper slopes, south and southwestern exposure). Spruce mortality followed a series of repeated droughts between 1990 and 2010. Mortality was negatively correlated with air humidity (r = -0.52), and precipitation (r = -0.57), and positively correlated with the prior year vapor pressure deficit (r = 0.47), and drought increase (r = 0.57). Mortality increased with the increase in occurrence of spring frosts (r = 0.5), and decreased with an increase in winter cloud cover (r = -0.37). Spruce mortality was negatively correlated with snow water accumulation (r = -0.81) and previous year anomalies in water soil content (r = -0.8). Weakened by water stress, spruce stands were attacked by pests and phytopathogens. Overall, spruce mortality in Belarussian forests was caused by drought episodes and drought increase in synergy with pest and phytopathogen attacks. Vast Picea abies mortality in Belarus and adjacent areas of Russia and Eastern Europe is a result of low adaptation of that species to increased drought. This indicates the necessity of spruce replacement by drought-tolerant indigenous (e.g., Pinus sylvestris, Querqus robur) or introduced (e.g., Larix sp. or Pseudotsuga menzieslii) species to obtain sustainable forest growth management.

  14. Climate-Induced Mortality of Spruce Stands in Belarus

    NASA Technical Reports Server (NTRS)

    Kharuk, Viacheslav I.; Im, Sergei T.; Dvinskaya, Maria L.; Golukov, Alexei S.; Ranson, Kenneth J.

    2015-01-01

    The aim of this work is an analysis of the causes of spruce (Picea abies L.) decline and mortality in Belarus. The analysis was based on forest inventory and Landsat satellite (land cover classification, climate variables (air temperature, precipitation, evaporation, vapor pressure deficit, SPEI drought index)), and GRACE-derived soil moisture estimation (equivalent of water thickness anomalies, EWTA). We found a difference in spatial patterns between dead stands and all stands (i.e., before mortality). Dead stands were located preferentially on relief features with higher water stress risk (i.e., higher elevations, steeper slopes, south and southwestern exposure). Spruce mortality followed a series of repeated droughts between 1990 and 2010. Mortality was negatively correlated with air humidity (r = -0.52), and precipitation (r = -0.57), and positively correlated with the prior year vapor pressure deficit (r = 0.47), and drought increase (r = 0.57). Mortality increased with the increase in occurrence of spring frosts (r = 0.5), and decreased with an increase in winter cloud cover (r = -0.37). Spruce mortality was negatively correlated with snow water accumulation (r = -0.81) and previous year anomalies in water soil content (r = -0.8). Weakened by water stress, spruce stands were attacked by pests and phytopathogens. Overall, spruce mortality in Belarussian forests was caused by drought episodes and drought increase in synergy with pest and phytopathogen attacks. Vast Picea abies mortality in Belarus and adjacent areas of Russia and Eastern Europe is a result of low adaptation of that species to increased drought. This indicates the necessity of spruce replacement by drought-tolerant indigenous (e.g., Pinus sylvestris, Querqus robur) or introduced (e.g., Larix sp. or Pseudotsuga menzieslii) species to obtain sustainable forest growth management.

  15. The variations of aluminium species in mountainous forest soils and its implications to soil acidification.

    PubMed

    Bradová, Monika; Tejnecký, Václav; Borůvka, Luboš; Němeček, Karel; Ash, Christopher; Šebek, Ondřej; Svoboda, Miroslav; Zenáhlíková, Jitka; Drábek, Ondřej

    2015-11-01

    Aluminium (Al) speciation is a characteristic that can be used as a tool for describing the soil acidification process. The question that was answered is how tree species (beech vs spruce) and type of soil horizon affect Al speciation. Our hypotesis is that spruce and beech forest vegetation are able to modify the chemical characteristics of organic horizon, hence the content of Al species. Moreover, these characteristics are seasonally dependent. To answer these questions, a detailed chromatographic speciation of Al in forest soils under contrasting tree species was performed. The Jizera Mountains area (Czech Republic) was chosen as a representative mountainous soil ecosystem. A basic forestry survey was performed on the investigated area. Soil and precipitation samples (throughfall, stemflow) were collected under both beech and spruce stands at monthly intervals from April to November during the years 2008-2011. Total aluminium content and Al speciation, pH, and dissolved organic carbon were determined in aqueous soil extracts and in precipitation samples. We found that the most important factors affecting the chemistry of soils, hence content of the Al species, are soil horizons and vegetation cover. pH strongly affects the amount of Al species under both forests. Fermentation (F) and humified (H) organic horizons contain a higher content of water extractable Al and Al(3+) compared to organo-mineral (A) and mineral horizons (B). With increasing soil profile depth, the amount of water extractable Al, Al(3+) and moisture decreases. The prevailing water-extractable species of Al in all studied soils and profiles under both spruce and beech forests were organically bound monovalent Al species. Distinct seasonal variations in organic and mineral soil horizons were found under both spruce and beech forests. Maximum concentrations of water-extractable Al and Al(3+) were determined in the summer, and the lowest in spring.

  16. The current status of red spruce in the eastern United States: distribution, population trends, and environmental drivers

    Treesearch

    Gregory Nowacki; Robert Carr; Michael. Van Dyck

    2010-01-01

    Red spruce (Picea rubens Sarg.) was affected by an array of direct (logging, fire, and grazing) and indirect human activities (acid deposition) over the past centuries. To adequately assess past impacts on red spruce, thus helping frame its restoration potential, requires a clear understanding of its current status. To achieve this, Forest and...

  17. Cold tolerance and photosystem function in a montane red spruce population: physiological relationships with foliar carbohydrates

    Treesearch

    P.G. Schaberg; G.R. Strimbeck; G.J. Hawley; D.H. DeHayes; J.B. Shane; P.F. Murakami; T.D. Perkins; J.R. Donnelly; B.L. Wong

    2000-01-01

    Red spruce (Picea rubens Sarg.) growing in northern montane forests of eastern North America appears to be distinctive with respect to at least two aspects of winter physiology. First, red spruce attains only a modest level of midwinter cold tolerance compared to other north temperate conifers and appears barely capable of avoiding freezing injury at...

  18. Site characteristics of red spruce witness tree locations in the uplands of West Virginia, USA

    Treesearch

    Melissa Thomas-Van Gundy; Michael Strager; James. Rentch

    2012-01-01

    Knowledge, both of the historical range of spruce-dominated forests and associated site conditions, is needed by land managers to help define restoration goals and potential sites for restoration. We used an existing digital database of witness trees listed in deeds from 1752 to 1899 to compare characteristics of red spruce (Picea rubens Sarg.) sites...

  19. How damage to balsam fir develops after a spruce budworm epidemic

    Treesearch

    Thomas F. McLintock

    1955-01-01

    From 1948 to 1952 a light to medium spruce budworm infestation occurred in the spruce-fir forests of northern Maine. During this period both the degree of infestation and the acreage affected fluctuated considerably, but the population remained below the damage level. In 1953 there was a general reduction in budworm population in all portions of northern Maine except a...

  20. Evaluation of tree risk in the spruce - fir region of the Northeast

    Treesearch

    Thomas F. McLintock

    1948-01-01

    In attempting to find possible means of combating recurrent epidemics of the spruce budworm in the Northeast, research has shown that forest management has considerable promise. Reduction in the proportion of balsam fir to spruce and attainment of the highest possible proportion of rapidly growing trees are expected to result in a less severe outbreak and a higher...

  1. Using environmental and site-specific variables to model current and potential distribution of red spruce forest habitat in West Virginia

    Treesearch

    Nathan Beane; James Rentch

    2010-01-01

    With the extensive loss of presettlement habitat for red spruce, this species is a high priority for restoration in West Virginia. The advent of climate change caused by human activity and the uncertainty of future environmental changes has also raised interests in the protection and restoration of red spruce ecosystems.

  2. Stand basal-area and tree-diameter growth in red spruce-fir forests in Maine, 1960-80

    Treesearch

    S.J. Zarnoch; D.A. Gansner; D.S. Powell; T.A. Birch; T.A. Birch

    1990-01-01

    Stand basal-area change and individual surviving red spruce d.b.h. growth from 1960 to 1980 were analyzed for red spruce-fir stands in Maine. Regression modeling was used to relate these measures of growth to stand and tree conditions and to compare growth throughout the period. Results indicate a decline in growth.

  3. Maximum size-density relationships for mixed softwoods in the northeastern USA

    Treesearch

    Dale S. Solomon; Lianjun Zhang

    2002-01-01

    The maximum size-density relationships or self-thinning lines were developed for three mix .ed-softwood climax forest habitats (hemlock-red spruce, spruce-fir, and cedar-black spruce) in the northeastern USA. The plot data were collected from an extensive data base used in growth studies from 1950 to 1970, and represented a wide range of species compositions, sites,...

  4. Exploring the Alaskan black spruce ecosystem: variability in species composition, ecosystem function, and fire history

    Treesearch

    T.N. Hollingsworth

    2008-01-01

    In this overview, I present extensive studies looking at the structure and function of the black spruce (Picea mariana) ecosystem of the boreal region of interior Alaska. One of the studies provides a classification of black spruce communities, the most abundant forest type in the region. Other studies examine large-scale processes that drive this...

  5. Patterns of Cross-Continental Variation in Tree Seed Mass in the Canadian Boreal Forest

    PubMed Central

    Liu, Jushan; Bai, Yuguang; Lamb, Eric G.; Simpson, Dale; Liu, Guofang; Wei, Yongsheng; Wang, Deli; McKenney, Daniel W.; Papadopol, Pia

    2013-01-01

    Seed mass is an adaptive trait affecting species distribution, population dynamics and community structure. In widely distributed species, variation in seed mass may reflect both genetic adaptation to local environments and adaptive phenotypic plasticity. Acknowledging the difficulty in separating these two aspects, we examined the causal relationships determining seed mass variation to better understand adaptability and/or plasticity of selected tree species to spatial/climatic variation. A total of 504, 481 and 454 seed collections of black spruce (Picea mariana (Mill.) B.S.P.), white spruce (Picea glauca (Moench) Voss) and jack pine (Pinus banksiana Lamb) across the Canadian Boreal Forest, respectively, were selected. Correlation analyses were used to determine how seed mass vary with latitude, longitude, and altitude. Structural Equation Modeling was used to examine how geographic and climatic variables influence seed mass. Climatic factors explained a large portion of the variation in seed mass (34, 14 and 29%, for black spruce, white spruce and jack pine, respectively), indicating species-specific adaptation to long term climate conditions. Higher annual mean temperature and winter precipitation caused greater seed mass in black spruce, but annual precipitation was the controlling factor for white spruce. The combination of factors such as growing season temperature and evapotranspiration, temperature seasonality and annual precipitation together determined seed mass of jack pine. Overall, sites with higher winter temperatures were correlated with larger seeds. Thus, long-term climatic conditions, at least in part, determined spatial variation in seed mass. Black spruce and Jack pine, species with relatively more specific habitat requirements and less plasticity, had more variation in seed mass explained by climate than did the more plastic species white spruce. As traits such as seed mass are related to seedling growth and survival, they potentially influence forest species composition in a changing climate and should be included in future modeling of vegetation shifts. PMID:23593392

  6. Associations between regional moisture gradient, tree species dominance, and downed wood abundance

    NASA Astrophysics Data System (ADS)

    Johnson, A. C.; Mills, J.

    2007-12-01

    Downed wood functions as a source of nurse logs, physical structure in streams, food, and carbon. Because downed wood is important in upland and aquatic habitats, an understanding of wood recruitment along a continuum from wet to dry landscapes is critical for both preservation of biodiversity and restoration of natural ecosystem structure and function. We assessed downed wood in public and private forests of Washington and Oregon by using a subset of the Forest Inventory and Analysis (FIA) database including 15,842 sampled conditions. Multivariate regression trees, ANOVA, and t-tests were used to discern environmental conditions most closely associated with abundance of woody debris. Of the 16 parameters included in the analysis, rainfall, forest ownership, number of damaged standing trees, and forest elevation were most indicative of woody debris abundance. The Hemlock/spruce Group, including hemlock, spruce, cedar, and white pine, most associated with wetter soils, had significantly more downed wood than 12 other forest groups. The Ponderosa Pine Group, indicative of drier sites with higher fire frequencies, included ponderosa pine, sugar pine, and incense cedar, and had significantly less downed wood volume. Overall, the amount of woody debris in either the Spruce/hemlock Group or the Ponderosa Pine Group did not change significantly as tree age increased from 5 to 350 years. Plots within the Hemlock/spruce with greater standing tree volume also had significantly greater downed wood volume. In contrast, greater downed wood volume was not associated with greater standing tree volume in the Ponderosa Pine Group. Knowledge of linkages among environmental variables and stand characteristics are useful in development of regional forest models aimed at understanding the effects of climate change and disturbance on forest succession.

  7. Modeling compensatory responses of ecosystem-scale water fluxes in forests affected by pine and spruce beetle mortality

    NASA Astrophysics Data System (ADS)

    Millar, D.; Ewers, B. E.; Peckham, S. D.; Mackay, D. S.; Frank, J. M.; Massman, W. J.; Reed, D. E.

    2015-12-01

    Mountain pine beetle (Dendroctonus ponderosae) and spruce beetle (Dendroctonus rufipennis) epidemics have led to extensive mortality in lodgepole pine (Pinus contorta) and Engelmann spruce (Picea engelmannii) forests in the Rocky Mountains of the western US. In both of these tree species, mortality results from hydraulic failure within the xylem, due to blue stain fungal infection associated with beetle attack. However, the impacts of these disturbances on ecosystem-scale water fluxes can be complex, owing to their variable and transient nature. In this work, xylem scaling factors that reduced whole-tree conductance were initially incorporated into a forest ecohydrological model (TREES) to simulate the impact of beetle mortality on evapotranspiration (ET) in both pine and spruce forests. For both forests, simulated ET was compared to observed ET fluxes recorded using eddy covariance techniques. Using xylem scaling factors, the model overestimated the impact of beetle mortality, and observed ET fluxes were approximately two-fold higher than model predictions in both forests. The discrepancy between simulated and observed ET following the onset of beetle mortality may be the result of spatial and temporal heterogeneity of plant communities within the foot prints of the eddy covariance towers. Since simulated ET fluxes following beetle mortality in both forests only accounted for approximately 50% of those observed in the field, it is possible that newly established understory vegetation in recently killed tree stands may play a role in stabilizing ecosystem ET fluxes. Here, we further investigate the unaccounted for ET fluxes in the model by breaking it down into multiple cohorts that represent live trees, dying trees, and understory vegetation that establishes following tree mortality.

  8. Modeling tree growth and stable isotope ratios of white spruce in western Alaska.

    NASA Astrophysics Data System (ADS)

    Boucher, Etienne; Andreu-Hayles, Laia; Field, Robert; Oelkers, Rose; D'Arrigo, Rosanne

    2017-04-01

    Summer temperatures are assumed to exert a dominant control on physiological processes driving forest productivity in interior Alaska. However, despite the recent warming of the last few decades, numerous lines of evidence indicate that the enhancing effect of summer temperatures on high latitude forest populations has been weakening. First, satellite-derived indices of photosynthetic activity, such as the Normalized-Difference Vegetation Index (NDVI, 1982-2005), show overall declines in productivity in the interior boreal forests. Second, some white spruce tree ring series strongly diverge from summer temperatures during the second half of the 20th century, indicating a persistent loss of temperature sensitivity of tree ring proxies. Thus, the physiological response of treeline forests to ongoing climate change cannot be accurately predicted, especially from correlation analysis. Here, we make use of a process-based dendroecological model (MAIDENiso) to elucidate the complex linkages between global warming and increases in atmospheric CO2 concentration [CO2] with the response of treeline white spruce stands in interior Alaska (Seward). In order to fully capture the array of processes controlling tree growth in the area, multiple physiological indicators of white spruce productivity are used as target variables: NDVI images, ring widths (RW), maximum density (MXD) and newly measured carbon and oxygen stable isotope ratios from ring cellulose. Based on these data, we highlight the processes and mechanisms responsible for the apparent loss of sensitivity of white spruce trees to recent climate warming and [CO2] increase in order to elucidate the sensitivity and vulnerability of these trees to climate change.

  9. Animal vectors of eastern dwarf mistletoe of black spruce.

    Treesearch

    Michael E. Ostry; Thomas H. Nicholls; D.W. French

    1983-01-01

    Describes a study to determine the importance of animals in the spread of eastern dwarf mistletoe of black spruce. Radio telemetry, banding, and color-marking techniques were used to study vectors of this forest pathogen.

  10. Near real time observational data collection for SPRUCE experiment- PakBus protocol for slow satellite connections

    NASA Astrophysics Data System (ADS)

    Krassovski, Misha; Hanson, Paul; Riggs, Jeff

    2017-04-01

    Climate change studies are one of the most important aspects of modern science and related experiments are getting bigger and more complex. One such experiment is the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE, http://mnspruce.ornl.gov) conducted in in northern Minnesota, 40 km north of Grand Rapids, in the USDA Forest Service Marcell Experimental Forest (MEF). The SPRUCE experimental mission is to assess ecosystem-level biological responses of vulnerable, high carbon terrestrial ecosystems to a range of climate warming manipulations and an elevated CO2 atmosphere. This manipulation experiment generates a lot of observational data and requires a reliable onsite data collection system, dependable methods to transfer data to a robust scientific facility, and real-time monitoring capabilities. This publication shares our experience of establishing near real time data collection and monitoring system via a satellite link using PakBus protocol.

  11. Near real time/low latency data collection for climate warming manipulations and an elevated CO2 SPRUCE experiment

    NASA Astrophysics Data System (ADS)

    Krassovski, M.; Hanson, P. J.; Riggs, J. S.; Nettles, W. R., IV

    2017-12-01

    Climate change studies are one of the most important aspects of modern science and related experiments are getting bigger and more complex. One such experiment is the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE, http://mnspruce.ornl.gov) conducted in in northern Minnesota, 40 km north of Grand Rapids, in the USDA Forest Service Marcell Experimental Forest (MEF). The SPRUCE experimental mission is to assess ecosystem-level biological responses of vulnerable, high carbon terrestrial ecosystems to a range of climate warming manipulations and an elevated CO2 atmosphere. This manipulation experiment generates a lot of observational data and requires a reliable onsite data collection system, dependable methods to transfer data to a robust scientific facility, and real-time monitoring capabilities. This presentation shares our experience of establishing near real time/low latency data collection and monitoring system using satellite communication.

  12. The effects of fire on the thermal stability of permafrost in lowland and upland black spruce forests of interior Alaska in a changing climate

    Treesearch

    E.E. Jafarov; V.E. Romanovsky; H. Genet; A.D. McGuire; S.S. Marchenko

    2013-01-01

    Fire is an important factor controlling the composition and thickness of the organic layer in the black spruce forest ecosystems of interior Alaska. Fire that burns the organic layer can trigger dramatic changes in the underlying permafrost, leading to accelerated ground thawing within a relatively short time. In this study, we addressed the following questions. (1)...

  13. Strip Clearcutting Did Not Degrade the Site in a Spruce-Fir Forest in Central Maine

    Treesearch

    Miroslaw M. Czapowskyi; Robert V. Rourke; Robert M. Frank

    1977-01-01

    Changes in the nutrient concentration in the forest floor and in the mineral soil were assessed on a mature spruce-fir stand in central Maine that had been harvested in 1965 by strip clearcutting. On part of the site, slash was left in place; on other parts it was removed, and on some it was burned. Eight years after the harvest, the clearcut areas tended to have...

  14. Paradigms and proboscideans in the southern Great Lakes region, USA

    USGS Publications Warehouse

    Saunders, J.J.; Grimm, E.C.; Widga, C.C.; Campbell, G.D.; Curry, B. Brandon; Grimley, D.A.; Hanson, P.R.; McCullum, J.P.; Oliver, J.S.; Treworgy, J.D.

    2010-01-01

    Thirteen new chronometric dates for Illinois proboscideans are considered in relation to well-dated pollen records from northeastern and central Illinois. These dates span an interval from 21,228 to 12,944 cal BP. When compared to pollen spectra, it is evident that Mammut americanum inhabited spruce (Picea) and black ash (Fraxinus nigra) forest during the B??lling-Aller??d (14,700-12,900 cal BP) and early Younger Dryas (12,900-11,650 cal BP) chronozones. Both Mammuthus jeffersonii and Mammuthus primigenius inhabited spruce dominated open-woodland during the Oldest Dryas chronozone, while M.??primigenius persisted in a forest of predominantly black ash during the Aller??d chronozone. A newly discovered specimen from Lincoln, IL, clarifies the taxonomic distinction between M. primigenius and M.??jeffersonii. Hitherto, a paradigm of proboscidean succession during the full- to late-glacial periods was based on the vegetation succession of steppe tundra-like vegetation to spruce forest to spruce-deciduous forest. The presumed proboscidean succession was that of cold, dry steppe-adapted M. primigenius succeeded by more mesic-tolerant M. jeffersonii that in turn was succeeded by the wet forest-adapted M.??americanum. Reported data do not support this view and indicate a need for re-evaluation of assumptions of proboscidean ecology and history, e.g., the environmental tolerances and habits of M.??primigenius in regions south of 55??N, and its dynamic relationship with other proboscidean taxa. ?? 2009 Elsevier Ltd and INQUA.

  15. Effect of Forest Management of Picea abies and Fagus sylvatica with Different Types of Felling on Carbon and Economic Balances in the Czech Republic

    NASA Astrophysics Data System (ADS)

    Plch, Radek; Pulkrab, Karel; Bukáček, Jan; Sloup, Roman; Cudlín, Pavel

    2016-10-01

    The selection of the most sustainable forest management under given site conditions needs suitable criteria and indicators. For this purpose, carbon and economic balance assessment, completed with environmental impact computation using the Life Cycle Assessment (LCA) were used. The aim of this study was to compare forestry operations and wood production of selected forest stands with different i) tree species composition (Norway spruce - Picea abies and European beech - Fagus sylvatica) and ii) type of felling (chainsaw and harvester). Carbon and economic balance methods consist in the comparison of quantified inputs (fossil fuels, electricity, used machinery, fertilizers, etc., converted into emission units of carbon in Mg of C- CO2-eq. or EUR) with quantified outputs (biomass production in Mg of carbon or EUR). In this contribution, similar forest stands (“forest site complexes”) in the 4th forest vegetation zone (in the Czech Republic approximately 400-700 m above sea-level) were selected. Forestry operations were divided into 5 main stages: i) seedling production, ii) stand establishment and pruning, iii) thinning and final cutting, iv) skidding, and v) secondary timber transport and modelled for one rotation period of timber production (ca. 100 years). The differences between Norway spruce and European beech forest stands in the carbon efficiency were relatively small while higher differences were achieved in the economic efficiency (forest stands with Norway spruce had a higher economic efficiency). Concerning the comparison of different types of felling in Norway spruce forest stands, the harvester use proved to induce significantly higher environmental impacts (emission of carbon) and lower economic costs. The comparison of forestry operation stages showed that the main part of carbon emissions, originating from fuel production and combustion, is connected with a thinning and final cutting, skidding and secondary timber transport in relations to different types of felling.

  16. Finders keepers, losers weepers - drought as a modifier of competition between European beech and Norway spruce -

    NASA Astrophysics Data System (ADS)

    Goisser, Michael; Blanck, Christian; Geppert, Uwe; Häberle, Karl-Heinz; Matyssek, Rainer; Grams, Thorsten E. E.

    2016-04-01

    Mixed stands of European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst.) frequently reflect over-yielding, when compared to respective monospecific stands. Over-yielding is attributed to enhanced resource uptake efficiency through niche complementarity alleviating species competition. Under climate change, however, with severe and frequent summer drought, water limitation may become crucial in modifying the competitive interaction between neighboring beech and spruce trees. In view of the demands by silvicultural practice, basic knowledge from experimental field work about competitive versus facilitative interaction in maturing mixed beech-spruce forests is scarce. To this end, we investigate species-specific drought response including underlying mechanisms of species interaction in a maturing group-wise mixed beech-spruce forest, amongst 60 and 53 adult trees of beech and spruce, respectively (spruce 65 ± 2, beech 85 ± 4 years old). Severe and repeated experimental drought is being induced over several years through a stand-scale approach of rain throughfall exclusion (Kranzberg Forest Roof Experiment, KROOF). The experimental design comprises 6 roofed (E, automated, closing only during rain) and 6 control (C) plots with a total area of almost 1800 square meters. In 2015 minimum predawn potentials of -2.16 MPa and -2.26 MPa were reached in E for beech and spruce respectively. At the leaf level, spruce displayed high drought susceptibility reflected by a distinct decrease in both stomatal conductance and net CO2 uptake rate by more than 80% each, suggesting isohydric response. Beech rather displayed anisohydry indicated by less pronounced yet significant reduction of stomatal conductance and net CO2 uptake rate by more than 55% and 45%, respectively. Under the C regime, a negative species interaction effect on stomatal conductance was found in beech, contrasting with a positive effect in spruce. However, drought reversed the effect of species interaction on stomatal conductance, suggesting competition release in beech and by contrast, a shift from facilitation to competition in spruce, if both species grew in mixture. Based on fine root distribution and soil moisture assessments, we interpret this reversed interaction effect as a consequence of different spatio-temporal patterns of soil water use in combination with enhanced root stratification between neighboring beech and spruce trees. Under humid climate conditions (i.e. with only short drought) the rather conservative strategy of spruce (isohydric response, root dominance in upper soil) appears to be advantageous, facilitating pre-emption of nutrients from litter mineralization and water from precipitation. During extended periods of drought, however, shallow rooting and early stomatal closure limits the accessibility to deep soil water and, hence, photosynthetic carbon assimilation, eventually constraining competitiveness of spruce. Beech rather benefits from reduced water consumption of its drought stressed competitor spruce. Regarding stomatal conductance, positive effects of beech-spruce interaction are overridden under extended periods of drought.

  17. Lagged cumulative spruce budworm defoliation affects the risk of fire ignition in Ontario, Canada.

    PubMed

    James, Patrick M A; Robert, Louis-Etienne; Wotton, B Mike; Martell, David L; Fleming, Richard A

    2017-03-01

    Detailed understanding of forest disturbance interactions is needed for effective forecasting, modelling, and management. Insect outbreaks are a significant forest disturbance that alters forest structure as well as the distribution and connectivity of combustible fuels at broad spatial scales. The effect of insect outbreaks on fire activity is an important but contentious issue with significant policy consequences. The eastern spruce budworm (Choristoneura fumiferana) is a native defoliating insect in eastern North America whose periodic outbreaks create large patches of dead fir and spruce trees. Of particular concern to fire and forest managers is whether these patches represent an increased fire risk, if so, for how long, and how the relationship between defoliation and fire risk varies through space and time. Previous work suggests a temporary increase in flammability in budworm-killed forests, but regional and seasonal variability in these relationships has not been examined. Using an extensive database on historical lightning-caused fire ignitions and spruce budworm defoliation between 1963 and 2000, we assess the relative importance of cumulative defoliation and fire weather on the probability of ignition in Ontario, Canada. We modeled fire ignition using a generalized additive logistic regression model that accounts for temporal autocorrelation in fire weather. We compared two ecoregions in eastern Ontario (Abitibi Plains) and western Ontario (Lake of the Woods) that differ in terms of climate, geomorphology, and forest composition. We found that defoliation has the potential to both increase and decrease the probability of ignition depending on the time scale, ecoregion, and season examined. Most importantly, we found that lagged spruce budworm defoliation (8-10 yr) increases the risk of fire ignition whereas recent defoliation (1 yr) can decrease this risk. We also found that historical defoliation has a greater influence on ignition risk during the spring than during the summer fire season. Given predicted increases in forest insect activity due to global change, these results represent important information for fire management agencies that can be used to refine existing models of fire risk. © 2016 by the Ecological Society of America.

  18. Effects of soil calcium and aluminum on the physiology of balsam fir and red spruce saplings in northern New England

    Treesearch

    Richard L. Boyce; Paul G. Schaberg; Gary J. Hawley; Joshua M. Halman; Paula F. Murakami

    2013-01-01

    We examined the influence of calcium (Ca) and aluminum (Al) nutrition on the foliar physiology of red spruce (Picea rubens Sarg.) and balsam fir [Abies balsamea (L.) Mill.] in northern New England, USA. At the Hubbard Brook Experimental Forest (NH, USA), spruce and fir saplings were sampled from control, Al-, and Ca-supplemented...

  19. Historical reconstructions of high-elevation spruce forests in the Appalachian mountains

    Treesearch

    Carolyn A. Copenheaver

    2010-01-01

    The objective of this study was to determine whether the historical distribution of a small, high-elevation red spruce stand could be reconstructed based upon historical records. The study site was Giles County, VA, where a small stand of red spruce exists today, indicating that it has been in this location for as long as the written record exists for this region....

  20. Drought-triggered western spruce budworm outbreaks in the Interior Pacific Northwest: A multi-century dendrochronological record

    Treesearch

    A. Flower; D. G. Gavin; E. K. Heyerdahl; R. A. Parsons; G. M. Cohn

    2014-01-01

    Douglas-fir forests in the interior Pacific Northwest are subject to sporadic outbreaks of the western spruce budworm, a species widely recognized as the most destructive defoliator in western North America. Outbreaks of the western spruce budworm often occur synchronously over broad regions and lead to widespread loss of leaf area and decrease in growth rates in...

  1. Red spruce ecosystem level changes following 14 years of chronic N fertilization

    Treesearch

    Steven G. McNulty; Johnny Boggs; John D. Aber; Lindsey Rustad; Allison Magill

    2005-01-01

    In the early 1980s, nitrogen (N) deposition was first postulated as a cause of N saturation and spruce mortality across the northeastern US. In 1988, a series of high elevation spruce-fir forest N addition plots were established on Mt. Ascutney (southeastern) Vermont to test this hypothesis. The paired plots each received, in addition to ambient N deposition, 15.7 kg...

  2. The forests of Maine: 2003

    Treesearch

    William H. McWilliams; Brett J. Butler; Laurence E. Caldwell; Douglas M. Griffith; Michael L. Hoppus; Kenneth M. Laustsen; Andrew J. Lister; Tonya W. Lister; Jacob W. Metzler; Randall S. Morin; Steven A. Sader; Lucretia B. Stewart; James R. Steinman; James, A. Westfall; David A. Williams; Andrew Whitman; Christopher W. Woodall; Christopher W. Woodall

    2005-01-01

    In 1999, the Maine Forest Service and USDA Forest Service's Forest Inventory and Analysis program implemented a new system for inventorying and monitoring Maine's forests. The effects of the spruce budworm epidemic continue to affect the composition, structure, and distribution of Maine's forested ecosystems. The area of forest land in Maine has remained...

  3. CANUSA mid-program report

    Treesearch

    David G. Grimble

    1981-01-01

    The Canada-United States Spruce Budworms Program (CANUSA) is a 6-year joint effort by the Department of the Environment, Canada, and the USDA Forest Service to develop methods for controlling spruce budworms in the Eastern and Western United States and in Canada.

  4. Biological decomposition efficiency in different woodland soils.

    PubMed

    Herlitzius, H

    1983-03-01

    The decomposition (meaning disappearance) of different leaf types and artificial leaves made from cellulose hydrate foil was studied in three forests - an alluvial forest (Ulmetum), a beech forest on limestone soil (Melico-Fagetum), and a spruce forest in soil overlying limestone bedrock.Fine, medium, and coarse mesh litter bags of special design were used to investigate the roles of abiotic factors, microorganisms, and meso- and macrofauna in effecting decomposition in the three habitats. Additionally, the experimental design was carefully arranged so as to provide information about the effects on decomposition processes of the duration of exposure and the date or moment of exposure. 1. Exposure of litter samples oor 12 months showed: a) Litter enclosed in fine mesh bags decomposed to some 40-44% of the initial amount placed in each of the three forests. Most of this decomposition can be attributed to abiotic factors and microoganisms. b) Litter placed in medium mesh litter bags reduced by ca. 60% in alluvial forest, ca. 50% in beech forest and ca. 44% in spruce forest. c) Litter enclosed in coarse mesh litter bags was reduced by 71% of the initial weights exposed in alluvial and beech forests; in the spruce forest decomposition was no greater than observed with fine and medium mesh litter bags. Clearly, in spruce forest the macrofauna has little or no part to play in effecting decomposition. 2. Sequential month by month exposure of hazel leaves and cellulose hydrate foil in coarse mesh litter bags in all three forests showed that one month of exposure led to only slight material losses, they did occur smallest between March and May, and largest between June and October/November. 3. Coarse mesh litter bags containing either hazel or artificial leaves of cellulose hydrate foil were exposed to natural decomposition processes in December 1977 and subsampled monthly over a period of one year, this series constituted the From-sequence of experiments. Each of the From-sequence samples removed was immediately replaced by a fresh litter bag which was left in place until December 1978, this series constituted the To-sequence of experiments. The results arising from the designated From- and To-sequences showed: a) During the course of one year hazel leaves decomposed completely in alluvial forest, almost completely in beech forest but to only 50% of the initial value in spruce forest. b) Duration of exposure and not the date of exposure is the major controlling influence on decomposition in alluvial forest, a characteristic reflected in the mirror-image courses of the From- and To-sequences curves with respect to the abscissa or time axis. Conversely the date of exposure and not the duration of exposure is the major controlling influence on decomposition in the spruce forest, a characteristic reflected in the mirror-image courses of the From-and To-sequences with respect to the ordinate or axis of percentage decomposition. c) Leaf powder amendment increased the decomposition rate of the hazel and cellulose hydrate leaves in the spruce forest but had no significant effect on their decomposition rate in alluvial and beech forests. It is concluded from this, and other evidence, that litter amendment by leaf fragments of phytophage frass in sites of low biological decomposition activity (eg. spruce) enhances decomposition processes. d) The time course of hazel leaf decomposition in both alluvial and beech forest is sigmoidal. Three s-phases are distinguished and correspond to the activity of microflora/microfauna, mesofauna/macrofauna, and then microflora/microfauna again. In general, the sigmoidal pattern of the curve can be considered valid for all decomposition processes occurring in terrestrial situations. It is contended that no decomposition (=disappearance) curve actually follows an e-type exponential function. A logarithmic linear regression can be constructed from the sigmoid curve data and although this facilitates inter-system comparisons it does not clearly express the dynamics of decomposition. 4. The course of the curve constructed from information about the standard deviations of means derived from the From- and To-sequence data does reflect the dynamics of litter decomposition. The three s-phases can be recognised and by comparing the actual From-sequence deviation curve with a mirror inversion representation of the To-sequence curve it is possible to determine whether decomposition is primarily controlled by the duration of exposure or the date of exposure. As is the case for hazel leaf decomposition in beech forest intermediate conditions can be readily recognised.

  5. Effects of calcium fertilization and acid mist on calcium concentration and cold tolerance of red spruce needles

    Treesearch

    G. R. Strimbeck; David R. Vann; Arthur H. Johnson

    1996-01-01

    Several studies have shown that exposure to acid mist impairs cold tolerance of red spruce foliage, predisposing it to winter injury, which appears to be a major factor in the decline of montane populations of the species. Other studies have shown increases in calcium (Ca) concentration in canopy throughfall in montane spruce-fir forests, and decreases in foliar Ca...

  6. Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest

    USGS Publications Warehouse

    Kueppers, Lara M.; Conlisk, Erin; Castanha, Cristina; Moyes, Andrew B.; Germino, Matthew; de Valpine, Perry; Torn, Margaret S.; Mitton, Jeffry B.

    2017-01-01

    Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations at the upper forest edge providing the seed best adapted to the alpine. Here, we test these expectations using a novel combination of common gardens, seeded with two widely distributed subalpine conifers, and climate manipulations replicated at three elevations. Infrared heaters raised temperatures in heated plots, but raised temperatures more in the forest than at or above treeline because strong winds at high elevation reduced heating efficiency. Watering increased season-average soil moisture similarly across sites. Contrary to expectations, warming reduced Engelmann spruce recruitment at and above treeline, as well as in the forest. Warming reduced limber pine first-year recruitment in the forest, but had no net effect on fourth-year recruitment at any site. Watering during the snow-free season alleviated some negative effects of warming, indicating that warming exacerbated water limitations. Contrary to expectations of local adaptation, low-elevation seeds of both species initially recruited more strongly than high-elevation seeds across the elevation gradient, although the low-provenance advantage diminished by the fourth year for Engelmann spruce, likely due to small sample sizes. High- and low-elevation provenances responded similarly to warming across sites for Engelmann spruce, but differently for limber pine. In the context of increasing tree mortality, lower recruitment at all elevations with warming, combined with lower quality, high-provenance seed being most available for colonizing the alpine, portends range contraction for Engelmann spruce. The lower sensitivity of limber pine to warming indicates a potential for this species to become more important in subalpine forest communities in the coming centuries.

  7. Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest.

    PubMed

    Kueppers, Lara M; Conlisk, Erin; Castanha, Cristina; Moyes, Andrew B; Germino, Matthew J; de Valpine, Perry; Torn, Margaret S; Mitton, Jeffry B

    2017-06-01

    Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations at the upper forest edge providing the seed best adapted to the alpine. Here, we test these expectations using a novel combination of common gardens, seeded with two widely distributed subalpine conifers, and climate manipulations replicated at three elevations. Infrared heaters raised temperatures in heated plots, but raised temperatures more in the forest than at or above treeline because strong winds at high elevation reduced heating efficiency. Watering increased season-average soil moisture similarly across sites. Contrary to expectations, warming reduced Engelmann spruce recruitment at and above treeline, as well as in the forest. Warming reduced limber pine first-year recruitment in the forest, but had no net effect on fourth-year recruitment at any site. Watering during the snow-free season alleviated some negative effects of warming, indicating that warming exacerbated water limitations. Contrary to expectations of local adaptation, low-elevation seeds of both species initially recruited more strongly than high-elevation seeds across the elevation gradient, although the low-provenance advantage diminished by the fourth year for Engelmann spruce, likely due to small sample sizes. High- and low-elevation provenances responded similarly to warming across sites for Engelmann spruce, but differently for limber pine. In the context of increasing tree mortality, lower recruitment at all elevations with warming, combined with lower quality, high-provenance seed being most available for colonizing the alpine, portends range contraction for Engelmann spruce. The lower sensitivity of limber pine to warming indicates a potential for this species to become more important in subalpine forest communities in the coming centuries. © 2016 John Wiley & Sons Ltd.

  8. Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kueppers, Lara M.; Conlisk, Erin; Castanha, Cristina

    Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations at the upper forest edge providing the seed best adapted to the alpine. Here, we test these expectations using a novel combination of common gardens, seeded with two widely distributed subalpine conifers, and climate manipulations replicated at three elevations. Infrared heaters raised temperatures in heated plots, butmore » raised temperatures more in the forest than at or above treeline because strong winds at high elevation reduced heating efficiency. Watering increased season-average soil moisture similarly across sites. Contrary to expectations, warming reduced Engelmann spruce recruitment at and above treeline, as well as in the forest. Warming reduced limber pine first-year recruitment in the forest, but had no net effect on fourth-year recruitment at any site. Watering during the snow-free season alleviated some negative effects of warming, indicating that warming exacerbated water limitations. Contrary to expectations of local adaptation, low-elevation seeds of both species initially recruited more strongly than high-elevation seeds across the elevation gradient, although the low-provenance advantage diminished by the fourth year for Engelmann spruce, likely due to small sample sizes. High- and low-elevation provenances responded similarly to warming across sites for Engelmann spruce, but differently for limber pine. In the context of increasing tree mortality, lower recruitment at all elevations with warming, combined with lower quality, high-provenance seed being most available for colonizing the alpine, portends range contraction for Engelmann spruce. The lower sensitivity of limber pine to warming indicates a potential for this species to become more important in subalpine forest communities in the coming centuries.« less

  9. Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest

    DOE PAGES

    Kueppers, Lara M.; Conlisk, Erin; Castanha, Cristina; ...

    2016-12-15

    Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations at the upper forest edge providing the seed best adapted to the alpine. Here, we test these expectations using a novel combination of common gardens, seeded with two widely distributed subalpine conifers, and climate manipulations replicated at three elevations. Infrared heaters raised temperatures in heated plots, butmore » raised temperatures more in the forest than at or above treeline because strong winds at high elevation reduced heating efficiency. Watering increased season-average soil moisture similarly across sites. Contrary to expectations, warming reduced Engelmann spruce recruitment at and above treeline, as well as in the forest. Warming reduced limber pine first-year recruitment in the forest, but had no net effect on fourth-year recruitment at any site. Watering during the snow-free season alleviated some negative effects of warming, indicating that warming exacerbated water limitations. Contrary to expectations of local adaptation, low-elevation seeds of both species initially recruited more strongly than high-elevation seeds across the elevation gradient, although the low-provenance advantage diminished by the fourth year for Engelmann spruce, likely due to small sample sizes. High- and low-elevation provenances responded similarly to warming across sites for Engelmann spruce, but differently for limber pine. In the context of increasing tree mortality, lower recruitment at all elevations with warming, combined with lower quality, high-provenance seed being most available for colonizing the alpine, portends range contraction for Engelmann spruce. The lower sensitivity of limber pine to warming indicates a potential for this species to become more important in subalpine forest communities in the coming centuries.« less

  10. Effects of acid deposition on calcium nutrition and health of Southern Appalachian spruce fir forests

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McLaughlin, S.B.; Wullschleger, S.; Stone, A.

    The role of acid deposition in the health of spruce fir forests in the Southern Appalachian Mountains has been investigated by a wide variety of experimental approaches during the past 10 years. These studies have proceeded from initial dendroecological documentation of altered growth patterns of mature trees to increasingly more focused ecophysiological research on the causes and characteristics of changes in system function associated with increased acidic deposition. Field studies across gradients in deposition and soil chemistry have been located on four mountains spanning 85 km of latitude within the Southern Appalachians. The conclusion that calcium nutrition is an importantmore » component regulating health of red spruce in the Southern Appalachians and that acid deposition significantly reduces calcium availability in several ways has emerged as a consistent result from multiple lines or research. These have included analysis of trends in wood chemistry, soil solution chemistry, foliar nutrition, gas exchange physiology, root histochemistry, and controlled laboratory and field studies in which acid deposition and/or calcium nutrition has been manipulated and growth and nutritional status of saplings or mature red spruce trees measured. This earlier research has led us to investigate the broader implications and consequences of calcium deficiency for changing resistance of spruce-fir forests to natural stresses. Current research is exploring possible relationships between altered calcium nutrition and shifts in response of Fraser fir to insect attack by the balsam wooly adelgid. In addition, changes in wood ultrastructural properties in relation to altered wood chemistry is being examined to evaluate its possible role in canopy deterioration, under wind and ice stresses typical of high elevation forests.« less

  11. Forest biomonitoring of the largest Slovene thermal power plant with respect to reduction of air pollution.

    PubMed

    Al Sayegh Petkovšek, Samar

    2013-02-01

    The condition of the forest ecosystem in the vicinity of the largest Slovene power plant [the Šoštanj Thermal Power Plant (ŠTPP)] was monitored during the period 1991-2008 by determining the total concentration of sulphur, ascorbic acid and chlorophyll in Norway spruce needles. After 1995, the introduction of cleaning devices at the ŠTPP dramatically reduced the former extremely high SO(2) and dust emissions. The most significant findings of this comprehensive, long-duration survey are as follows: (1) the chosen parameters are suitable bioindicators of stress caused by air pollution in Norway spruce needles; they reflect both spatial and temporal variations in air pollution as well as the degree of efficiency of the cleaning devices; (2) observations show that the physiological condition of Norway spruce in northern Slovenia has significantly improved since 1995, when the first desulphurization device at ŠTPP was built, together with a reduction in the area influenced by pollution from ŠTPP; (3) metabolic processes in spruce needles react to air pollution according to the severity of the pollution and the length of exposure; exposure to high SO(2) ambient levels and/or spread over a long duration can damage the antioxidant defence mechanisms of spruce trees as well as diminishing the concentration of ascorbic acid; (4) a reduction in the exposure to air pollution improves the vitality of the trees (e.g. higher concentrations of total (a + b) chlorophyll), as well as restoring their defence capabilities as shown by higher concentrations of ascorbic acid; and (5) forest monitoring should be continued and focused on integrating the effects of multiple stressors, which can additionally affect a forest ecosystem.

  12. Nonlinearities, scale-dependence, and individualism of boreal forest trees to climate forcing

    NASA Astrophysics Data System (ADS)

    Wolken, J. M.; Mann, D. H.; Grant, T. A., III; Lloyd, A. H.; Hollingsworth, T. N.

    2013-12-01

    Our understanding of the climate-growth relationships of trees are complicated by the nonlinearity and variability of these responses through space and time. Furthermore, trees growing at the same site may exhibit opposing growth responses to climate, a phenomenon termed growth divergence. To date the majority of dendrochronological studies in Interior Alaska have involved white spruce growing at treeline, even though black spruce is the most abundant tree species. Although changing climate-growth relationships have been observed in black spruce, there is little known about the multivariate responses of individual trees to temperature and precipitation and whether or not black spruce exhibits growth divergences similar to those documented for white spruce. To evaluate the occurrence of growth divergences in black spruce, we collected cores from trees growing on a steep, north-facing toposequence having a gradient in environmental parameters. Our overall goal was to assess how the climate-growth relationships of black spruce change over space and time. Specifically, we evaluated how topography influences the climate-growth relationships of black spruce and if the growth responses to climate are homogeneous. At the site-level most trees responded negatively to temperature and positively to precipitation, while at the tree-level black spruce exhibited heterogenous growth responses to climate that varied in both space (i.e., between sites) and time (i.e., seasonally and annually). There was a dominant response-type at each site, but there was also considerable variability in the proportion of trees exhibiting each response-type combination. Even in a climatically extreme setting like Alaska's boreal forest, tree responses to climate variability are spatially and temporally complex, as well as highly nonlinear.

  13. Soil charcoal from the plains to tundra in the Colorado Front Range

    NASA Astrophysics Data System (ADS)

    Sanford, R. L.; Licata, C.

    2010-12-01

    Throughout the forests of the central Rockies, soil charcoal from Holocene wildfires has been produced in response to wildland natural fire regimes. The extent and spatial distribution of soil charcoal production is poorly documented in this region, especially with regard to forests and shrublands at different elevations. Soil charcoal is a super-passive C pool derived from woody biomass that can be sequestered for millennia in forest soils. Recent research indicates that soil charcoal may promote enhanced soil fertility. Additionally, soil charcoal is an often overlooked component of soil C mass and flux. We hypothesize that differences in forest and shrubland fire regimes over the millennia have resulted in different soil charcoal amounts. Geospatial data were used to locate random sample plots in foothills shrublands (Cercocarpus montanus), and four forest types; ponderosa pine (Pinus ponderosa), Douglas-fir (Pseudotsuga menziesii), lodgepole pine (Pinus contorta) and spruce-fir (Picea engelmannii - Abies lasiocarpa). Sample plots were stratified to occur with the mid 200 m elevation band of each vegetation type with east aspect, and 10-30% slope. Soils were sampled widely at 0-10 cm depth and analyzed for total soil C and soil charcoal C via chemical digestion and dry combustion techniques. Overall, soil charcoal is four times more abundant in spruce-fir forests than in foothills shrublands (1.9 +/- 0.92 Mg C/ha versus 0.54 +/- 0.44 Mg C/ha). Soil charcoal is also abundant in lodgepole pine and ponderosa pine soils (1.4 +/- 1.02 Mg C/ha and 1.4 +/- 0.54 Mg C/ha respectively) but is less plentiful in Douglas-fir soils (1.0 +/- 0.67). Spruce-fir forests have the most above ground biomass, slower decomposition rates and a less frequent mean fire return interval than the other four forests, hence it makes sense that high per-fire rates of charcoal production would occur in the spruce-fir zone, given large amounts of surface fuels at the time of fire. In contrast, low amounts of coarse woody debris in ponderosa, lodgepole, and shrub communities would cause less charcoal to form, despite higher fire frequencies. The Douglas-fir soil charcoal seems anomalously low, but it may reflect a combination of low forest floor woody debris and low fire frequency. Foothills shrublands have the least biomass, comparatively rapid decomposition rates and a more frequent mean fire return interval. We propose that high biomass and slow turnover rates in the spruce-fir forests creates conditions for relatively higher net soil charcoal accumulation.

  14. Minnesota's forest resources in 2004

    Treesearch

    Patrick D. Miles; Gary J. Brand; Manfred E. Mielke

    2006-01-01

    This report presents forest statistics based on the five annual inventory panels measured from 2000 through 2004. Forest area is estimated at 16.2 million acres or 32 percent of the total land area in the State. Important pests in Minnesota forests include the forest tent caterpillar and spruce budworm.

  15. Late winter and early spring home range and habitat use of the endangered Carolina northern flying squirrel in western North Carolina

    USGS Publications Warehouse

    Ford, W. Mark; Kelly, Christine A.; Rodrigue, Jane L.; Odom, Richard H.; Newcomb, Douglas; Gilley, L. Michelle; Diggins, Corinne A.

    2014-01-01

    The Carolina northern flying squirrel Glaucomys sabrinus coloratus is an endangered subspecies that is restricted to high elevation forests in the southern Appalachian Mountains. Owing to rugged terrain and nocturnal habits, the subspecies’ natural history, home range characteristics and habitat preferences are poorly known. We radio-tracked 3 female and 2 male Carolina northern flying squirrels during late winter through spring 2012 in the Pisgah National Forest, North Carolina, USA. Tracked squirrels used 13 yellow birch Betula alleghaniensis and 9 red spruce Picea rubens as diurnal dens. Ten of the yellow birch dens were in cavities, whereas the remainders were dreys. Conversely, 8 of the red spruce dens were dreys and one was in a cavity. Mean (±SE) female 95 and 50% adaptive kernel home ranges were 6.50 ± 2.19 and 0.93 ± 0.33 ha, respectively, whereas the corresponding values for males were 12.6 ± 0.9 and 1.45 ± 0.1 ha, respectively. Squirrels used red spruce stands with canopies >20 m more than expected based on availability at the landscape and home range scales. Results should be interpreted cautiously because of small sample sizes and seasonal observations; however, they provide evidence that although northern hardwoods such as yellow birch are an important den habitat component, mature red spruce-dominated habitats with complex structure provide foraging habitats and are also den habitat. Our findings support efforts to improve the structural condition of extant red spruce forests and/or increase red spruce acreage to potentially benefit Carolina northern flying squirrels.

  16. Environmental Assessment for the Joint Advanced Weapons Scoring System Installation in the Oklahoma Range, Donnelly West Training Area, Alaska

    DTIC Science & Technology

    2008-06-01

    complex, formally known as the Birch Creek Shist. Figure 3-3 – Proposed Donnelly Ridge Tower Site 3.1.4 Soils 3.1.4.1 The Delta Creek channel...in elevation, and fire history. Major vegetation types include white and black spruce coniferous forests; paper birch and poplar broadleaf forests...consists primarily of black spruce, dwarf birch , willow, sedges, and grasses (Figure 3-4). 3.2.2 Wildlife 3.2.2.1 The lands associated

  17. Remote sensing applications to forest vegetation classification and conifer vigor loss due to dwarf mistletoe

    NASA Technical Reports Server (NTRS)

    Douglass, R. W.; Meyer, M. P.; French, D. W.

    1972-01-01

    Criteria was established for practical remote sensing of vegetation stress and mortality caused by dwarf mistletoe infections in black spruce subboreal forest stands. The project was accomplished in two stages: (1) A fixed tower-tramway site in an infected black spruce stand was used for periodic multispectral photo coverage to establish basic film/filter/scale/season/weather parameters; (2) The photographic combinations suggested by the tower-tramway tests were used in low, medium, and high altitude aerial photography.

  18. Sbexpert users guide (version 1.0): A knowledge-based decision-support system for spruce beetle management. Forest Service general technical report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reynolds, K.M.; Holsten, E.H.; Werner, R.A.

    1995-03-01

    SBexpert version 1.0 is a knowledge-based decision-support system for management of spruce beetle developed for use in Microsoft Windows. The users guide provides detailed instructions on the use of all SBexpert features. SBexpert has four main subprograms; introduction, analysis, textbook, and literature. The introduction is the first of the five subtopics in the SBexpert help system. The analysis topic is an advisory system for spruce beetle management that provides recommendation for reducing spruce beetle hazard and risk to spruce stands and is the main analytical topic in SBexpert. The textbook and literature topics provide complementary decision support for analysis.

  19. Pulpability of beetle-killed spruce. Forest Service research paper

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scott, G.M.; Bormett, D.W.; Sutherland, N.R.

    1996-08-01

    Infestation of the Dendroctonus rufipennis beetle has resulted in large stands of dead and dying timber on the Kenai Peninsula in Alaska. Tests were conducted to evaluate the value of beetle-killed spruce as pulpwood. The results showed that live and dead spruce wood can be pulped effectively. The two least deteriorated classes and the most deteriorated class of logs had similar characteristics when pulped; the remaining class had somewhat poorer pulpability.

  20. Calcium addition at the Hubbard Brook Experimental Forest increases the capacity for stress tolerance and carbon capture in red spruce (Picea rubens) trees during the cold season

    Treesearch

    Paul G. Schaberg; Rakesh Minocha; Stephanie Long; Joshua M. Halman; Gary J. Hawley; Christopher Eagar

    2011-01-01

    Red spruce (Picea rubens Sarg.) trees are uniquely vulnerable to foliar freezing injury during the cold season (fall and winter), but are also capable of photosynthetic activity if temperatures moderate. To evaluate the influence of calcium (Ca) addition on the physiology of red spruce during the cold season, we measured concentrations of foliar...

  1. Patterns of Canopy and Surface Layer Consumption in a Boreal Forest Fire from Repeat Airborne Lidar

    NASA Technical Reports Server (NTRS)

    Alonzo, Michael; Morton, Douglas C.; Cook, Bruce D.; Andersen, Hans-Erik; Babcock, Chad; Pattison, Robert

    2017-01-01

    Fire in the boreal region is the dominant agent of forest disturbance with direct impacts on ecosystem structure, carbon cycling, and global climate. Global and biome-scale impacts are mediated by burn severity, measured as loss of forest canopy and consumption of the soil organic layer. To date, knowledge of the spatial variability in burn severity has been limited by sparse field sampling and moderate resolution satellite data. Here, we used pre- and post-fire airborne lidar data to directly estimate changes in canopy vertical structure and surface elevation for a 2005 boreal forest fire on Alaskas Kenai Peninsula. We found that both canopy and surface losses were strongly linked to pre-fire species composition and exhibited important fine-scale spatial variability at sub-30m resolution. The fractional reduction in canopy volume ranged from 0.61 in lowland black spruce stands to 0.27 in mixed white spruce and broad leaf forest. Residual structure largely reflects standing dead trees, highlighting the influence of pre-fire forest structure on delayed carbon losses from above ground biomass, post-fire albedo, and variability in understory light environments. Median loss of surface elevation was highest in lowland black spruce stands (0.18 m) but much lower in mixed stands (0.02 m), consistent with differences in pre-fire organic layer accumulation. Spatially continuous depth-of-burn estimates from repeat lidar measurements provide novel information to constrain carbon emissions from the surface organic layer and may inform related research on post-fire successional trajectories. Spectral measures of burn severity from Landsat were correlated with canopy (r = 0.76) and surface (r = -0.71) removal in black spruce stands but captured less of the spatial variability in fire effects for mixed stands (canopy r = 0.56, surface r = -0.26), underscoring the difficulty in capturing fire effects in heterogeneous boreal forest landscapes using proxy measures of burn severity from Landsat.

  2. Patterns of canopy and surface layer consumption in a boreal forest fire from repeat airborne lidar

    NASA Astrophysics Data System (ADS)

    Alonzo, Michael; Morton, Douglas C.; Cook, Bruce D.; Andersen, Hans-Erik; Babcock, Chad; Pattison, Robert

    2017-05-01

    Fire in the boreal region is the dominant agent of forest disturbance with direct impacts on ecosystem structure, carbon cycling, and global climate. Global and biome-scale impacts are mediated by burn severity, measured as loss of forest canopy and consumption of the soil organic layer. To date, knowledge of the spatial variability in burn severity has been limited by sparse field sampling and moderate resolution satellite data. Here, we used pre- and post-fire airborne lidar data to directly estimate changes in canopy vertical structure and surface elevation for a 2005 boreal forest fire on Alaska’s Kenai Peninsula. We found that both canopy and surface losses were strongly linked to pre-fire species composition and exhibited important fine-scale spatial variability at sub-30 m resolution. The fractional reduction in canopy volume ranged from 0.61 in lowland black spruce stands to 0.27 in mixed white spruce and broadleaf forest. Residual structure largely reflects standing dead trees, highlighting the influence of pre-fire forest structure on delayed carbon losses from aboveground biomass, post-fire albedo, and variability in understory light environments. Median loss of surface elevation was highest in lowland black spruce stands (0.18 m) but much lower in mixed stands (0.02 m), consistent with differences in pre-fire organic layer accumulation. Spatially continuous depth-of-burn estimates from repeat lidar measurements provide novel information to constrain carbon emissions from the surface organic layer and may inform related research on post-fire successional trajectories. Spectral measures of burn severity from Landsat were correlated with canopy (r = 0.76) and surface (r = -0.71) removal in black spruce stands but captured less of the spatial variability in fire effects for mixed stands (canopy r = 0.56, surface r = -0.26), underscoring the difficulty in capturing fire effects in heterogeneous boreal forest landscapes using proxy measures of burn severity from Landsat.

  3. Succession after fire: variation in \\delta13C of organic tissues and respired CO2 in boreal forests

    NASA Astrophysics Data System (ADS)

    Fessenden, J. E.; Li, H.; Mack, M.; Schuur, T.; Warren, S.; Randerson, J. T.

    2001-12-01

    Isotope ratios of carbon dioxide and leaf organic matter were measured in 5 neighboring forests of varying ages: 7, 14, 45, 140, and 160 years. These forests are composed primarily of black spruce (Picea Mariana) and quaking aspen (Populus tremuloides) with a shift in species dominance from aspen to spruce 50 years after fire disturbance. Research on the carbon isotope ratios of leaf material and CO2 was conducted to look for influences from species composition, forest age, and time after most recent burn. Samples of organic \\delta13C in whole leaf tissue were collected from the dominant species of each forest. Concurrent aboveground NPP measurements allowed us to estimate total ecosystem \\delta13C by providing a method for weighting \\delta13C of individual species and plant tissues. \\delta13CO2 and [CO2] were measured on canopy CO2 to determine the isotopic ratio of ecosystem respiration. The atmospheric results indicated that the \\delta13C of ecosystem respiration changes with successional stage. Specifically, the aspen dominating forests showed 13C depleted values relative to the spruce dominated forests. Organic results showed more 13C-enriched values with increased forest age and vegetation functional type. Specifically, oldest trees within the coniferous species had the most 13C-enriched values in leaf tissues. These results suggest that increases in the disturbance regime of northern boreal forests will lead to a decrease in the \\delta13C of ecosystem carbon with consequences for the atmospheric \\delta13C budget.

  4. SOIL CO2 EFFLUX FROM ISOTOPICALLY LABELED BEECH AND SPRUCE IN SOUTHERN GERMANY

    EPA Science Inventory

    • Carbon acquisition and transport to roots in forest trees is difficult to quantify and is affected by a number of factors, including micrometeorology and anthropogenic stresses. The canopies of mature European beech (Fagus sylvatica) and Norway spruce (Picea abies) were expose...

  5. Thermokarst rates intensify due to climate change and forest fragmentation in an Alaskan boreal forest lowland.

    PubMed

    Lara, Mark J; Genet, Hélène; McGuire, Anthony D; Euskirchen, Eugénie S; Zhang, Yujin; Brown, Dana R N; Jorgenson, Mark T; Romanovsky, Vladimir; Breen, Amy; Bolton, William R

    2016-02-01

    Lowland boreal forest ecosystems in Alaska are dominated by wetlands comprised of a complex mosaic of fens, collapse-scar bogs, low shrub/scrub, and forests growing on elevated ice-rich permafrost soils. Thermokarst has affected the lowlands of the Tanana Flats in central Alaska for centuries, as thawing permafrost collapses forests that transition to wetlands. Located within the discontinuous permafrost zone, this region has significantly warmed over the past half-century, and much of these carbon-rich permafrost soils are now within ~0.5 °C of thawing. Increased permafrost thaw in lowland boreal forests in response to warming may have consequences for the climate system. This study evaluates the trajectories and potential drivers of 60 years of forest change in a landscape subjected to permafrost thaw in unburned dominant forest types (paper birch and black spruce) associated with location on elevated permafrost plateau and across multiple time periods (1949, 1978, 1986, 1998, and 2009) using historical and contemporary aerial and satellite images for change detection. We developed (i) a deterministic statistical model to evaluate the potential climatic controls on forest change using gradient boosting and regression tree analysis, and (ii) a 30 × 30 m land cover map of the Tanana Flats to estimate the potential landscape-level losses of forest area due to thermokarst from 1949 to 2009. Over the 60-year period, we observed a nonlinear loss of birch forests and a relatively continuous gain of spruce forest associated with thermokarst and forest succession, while gradient boosting/regression tree models identify precipitation and forest fragmentation as the primary factors controlling birch and spruce forest change, respectively. Between 1950 and 2009, landscape-level analysis estimates a transition of ~15 km² or ~7% of birch forests to wetlands, where the greatest change followed warm periods. This work highlights that the vulnerability and resilience of lowland ice-rich permafrost ecosystems to climate changes depend on forest type. © 2015 John Wiley & Sons Ltd.

  6. Thermokarst rates intensify due to climate change and forest fragmentation in an Alaskan boreal forest lowland

    USGS Publications Warehouse

    Lara, M.; Genet, Helene; McGuire, A. David; Euskirchen, Eugénie S.; Zhang, Yujin; Brown, Dana R. N.; Jorgenson, M.T.; Romanovsky, V.; Breen, Amy L.; Bolton, W.R.

    2016-01-01

    Lowland boreal forest ecosystems in Alaska are dominated by wetlands comprised of a complex mosaic of fens, collapse-scar bogs, low shrub/scrub, and forests growing on elevated ice-rich permafrost soils. Thermokarst has affected the lowlands of the Tanana Flats in central Alaska for centuries, as thawing permafrost collapses forests that transition to wetlands. Located within the discontinuous permafrost zone, this region has significantly warmed over the past half-century, and much of these carbon-rich permafrost soils are now within ~0.5 °C of thawing. Increased permafrost thaw in lowland boreal forests in response to warming may have consequences for the climate system. This study evaluates the trajectories and potential drivers of 60 years of forest change in a landscape subjected to permafrost thaw in unburned dominant forest types (paper birch and black spruce) associated with location on elevated permafrost plateau and across multiple time periods (1949, 1978, 1986, 1998, and 2009) using historical and contemporary aerial and satellite images for change detection. We developed (i) a deterministic statistical model to evaluate the potential climatic controls on forest change using gradient boosting and regression tree analysis, and (ii) a 30 × 30 m land cover map of the Tanana Flats to estimate the potential landscape-level losses of forest area due to thermokarst from 1949 to 2009. Over the 60-year period, we observed a nonlinear loss of birch forests and a relatively continuous gain of spruce forest associated with thermokarst and forest succession, while gradient boosting/regression tree models identify precipitation and forest fragmentation as the primary factors controlling birch and spruce forest change, respectively. Between 1950 and 2009, landscape-level analysis estimates a transition of ~15 km² or ~7% of birch forests to wetlands, where the greatest change followed warm periods. This work highlights that the vulnerability and resilience of lowland ice-rich permafrost ecosystems to climate changes depend on forest type.

  7. Post-fire forest dynamics and climate variability affect spatial and temporal properties of spruce beetle outbreaks on a Sky Island mountain range

    Treesearch

    Christopher D. O' Connor; Ann M. Lynch; Donald A. Falk; Thomas W. Swetnam

    2014-01-01

    The spruce beetle (Dendroctonus rufipennis) is known for extensive outbreaks resulting in high spruce mortality, but several recent outbreaks in the western United States have been among the largest and most severe in the documentary record. In the Pinaleño Mountains of southeast Arizona, U.S.A., an outbreak in the mid-1990s resulted in 85% mortality of Engelmann...

  8. Dispersal of forest insects

    NASA Technical Reports Server (NTRS)

    Mcmanus, M. L.

    1979-01-01

    Dispersal flights of selected species of forest insects which are associated with periodic outbreaks of pests that occur over large contiguous forested areas are discussed. Gypsy moths, spruce budworms, and forest tent caterpillars were studied for their massive migrations in forested areas. Results indicate that large dispersals into forested areas are due to the females, except in the case of the gypsy moth.

  9. Effects of Plant Leachates from Four Boreal Understorey Species on Soil N Mineralization, and White Spruce (Picea glauca) Germination and Seedling Growth

    PubMed Central

    CASTELLS, EVA; PEÑUELAS, JOSEP; VALENTINE, DAVID W.

    2005-01-01

    • Background and Aims Natural regeneration of white spruce (Picea glauca) after disturbance has been reported to be very poor. Here a study was made to determine whether C compounds released from understorey species growing together with white spruce could be involved in this regeneration failure, either by (1) changing soil nutrient dynamics, (2) inhibiting germination, and/or (3) delaying seedling growth. • Methods Foliage leachates were obtained from two shrubs (Ledum palustre and Empetrum hermaphroditum) and one bryophyte (Sphagnum sp.) with high phenolic compound concentrations that have been reported to depress growth of conifers in boreal forests, and, as a comparison, one bryophyte (Hylocomium splendens) with negligible phenolic compounds. Mineral soil from a white spruce forest was amended with plant leachates to examine the effect of each species on net N mineralization. Additionally, white spruce seeds and seedlings were watered with plant leachates to determine their effects on germination and growth. • Key Results Leachates from the shrubs L. palustre and E. hermaphroditum contained high phenolic compound concentrations and dissolved organic carbon (DOC), while no detectable levels of C compounds were released from the bryophytes Sphagnum sp. or H. splendens. A decrease in net N mineralization was determined in soils amended with L. palustre or E. hermaphroditum leachates, and this effect was inversely proportional to the phenolic concentrations, DOC and leachate C/N ratio. The total percentage of white spruce germination and the growth of white spruce seedlings were similar among treatments. • Conclusions These results suggest that the shrubs L. palustre and E. hermaphroditum could negatively affect the performance of white spruce due to a decrease in soil N availability, but not by direct effects on plant physiology. PMID:15802310

  10. Effects of plant leachates from four boreal understorey species on soil N mineralization, and white spruce (Picea glauca) germination and seedling growth.

    PubMed

    Castells, Eva; Peñuelas, Josep; Valentine, David W

    2005-06-01

    Natural regeneration of white spruce (Picea glauca) after disturbance has been reported to be very poor. Here a study was made to determine whether C compounds released from understorey species growing together with white spruce could be involved in this regeneration failure, either by (1) changing soil nutrient dynamics, (2) inhibiting germination, and/or (3) delaying seedling growth. Foliage leachates were obtained from two shrubs (Ledum palustre and Empetrum hermaphroditum) and one bryophyte (Sphagnum sp.) with high phenolic compound concentrations that have been reported to depress growth of conifers in boreal forests, and, as a comparison, one bryophyte (Hylocomium splendens) with negligible phenolic compounds. Mineral soil from a white spruce forest was amended with plant leachates to examine the effect of each species on net N mineralization. Additionally, white spruce seeds and seedlings were watered with plant leachates to determine their effects on germination and growth. Leachates from the shrubs L. palustre and E. hermaphroditum contained high phenolic compound concentrations and dissolved organic carbon (DOC), while no detectable levels of C compounds were released from the bryophytes Sphagnum sp. or H. splendens. A decrease in net N mineralization was determined in soils amended with L. palustre or E. hermaphroditum leachates, and this effect was inversely proportional to the phenolic concentrations, DOC and leachate C/N ratio. The total percentage of white spruce germination and the growth of white spruce seedlings were similar among treatments. These results suggest that the shrubs L. palustre and E. hermaphroditum could negatively affect the performance of white spruce due to a decrease in soil N availability, but not by direct effects on plant physiology.

  11. Fine root morphological adaptations in Scots pine, Norway spruce and silver birch along a latitudinal gradient in boreal forests.

    PubMed

    Ostonen, Ivika; Lõhmus, Krista; Helmisaari, Heljä-Sisko; Truu, Jaak; Meel, Signe

    2007-11-01

    Variability in short root morphology of the three main tree species of Europe's boreal forest (Norway spruce (Picea abies L. Karst.), Scots pine (Pinus sylvestris L.) and silver birch (Betula pendula Roth)) was investigated in four stands along a latitudinal gradient from northern Finland to southern Estonia. Silver birch and Scots pine were present in three stands and Norway spruce was present in all stands. For three fertile Norway spruce stands, fine root biomass and number of root tips per stand area or unit basal area were assessed from north to south. Principal component analysis indicated that short root morphology was significantly affected by tree species and site, which together explained 34.7% of the total variability. The range of variation in mean specific root area (SRA) was 51-74, 60-70 and 84-124 m(2) kg(-1) for Norway spruce, Scots pine and silver birch, respectively, and the corresponding ranges for specific root length were 37-47, 40-48 and 87-97 m g(-1). The range of variation in root tissue density of Norway spruce, Scots pine and silver birch was 113-182, 127-158 and 81-156 kg m(-3), respectively. Sensitivity of short root morphology to site conditions decreased in the order: Norway spruce > silver birch > Scots pine. Short root SRA increased with site fertility in all species. In Norway spruce, fine root biomass and number of root tips per m(2) decreased from north to south. The differences in morphological parameters among sites were significant but smaller than the site differences in fine root biomass and number of root tips.

  12. Estimating forest species composition using a multi-sensor approach

    Treesearch

    P.T. Wolter

    2009-01-01

    The magnitude, duration, and frequency of forest disturbance caused by the spruce budworm and forest tent caterpillar has increased over the last century due to a shift in forest species composition linked to historical fire suppression, forest management, and pesticide application that has fostered the increase in dominance of host tree species. Modeling approaches...

  13. Dynamics of forest health status in Slovakia from 1987 to 1994

    Treesearch

    Julius Oszlanyi

    1998-01-01

    Slovakia is a mountainous and forested country (40.6 percent forest cover) in central Europe and has a large variety of vegetation zones, forest types, and a rich diversity of forest tree species. The most important tree species are beech (Fagus sylvatica L.), Norway spruce (Picea abies Karst.), oak species (Quercus...

  14. Western Spruce Budworm

    Treesearch

    David G. Fellin; Jerald E. Dewey

    1982-01-01

    The western spruce budworm, Choristoneura occidentalis Freeman, is the most widely distributed and destructive defoliator of coniferous forests in Western North America. It is one of nearly a dozen Choristoneura species, subspecies, or forms, with a complexity of variation among populations found throughout much of the United States and Canada. It occurs in the Rocky...

  15. Multipartite Symbioses Among Fungi, Mites, Nematodes, and the Spruce Beetle, Dendroctonus rufipennis.

    Treesearch

    Yasmin Cardoza; John Moser; Kier Klepzizg; Raffa Kenneth

    2008-01-01

    The spruce beetle, Dendroctonus rufipennis, is an eruptive forest pest of signifcant economic and ecological importance. D. rufipennis has symbiotic associations with a number of microorganisms, especially the ophiostomatoid fungus Leptographium abietinum. The nature of this interaction is only partially understood. Additionally, mite and nematode associates can...

  16. Stable carbon isotope analysis reveals widespread drought stress in boreal black spruce forests.

    PubMed

    Walker, Xanthe J; Mack, Michelle C; Johnstone, Jill F

    2015-08-01

    Unprecedented rates of climate warming over the past century have resulted in increased forest stress and mortality worldwide. Decreased tree growth in association with increasing temperatures is generally accepted as a signal of temperature-induced drought stress. However, variations in tree growth alone do not reveal the physiological mechanisms behind recent changes in tree growth. Examining stable carbon isotope composition of tree rings in addition to tree growth can provide a secondary line of evidence for physiological drought stress. In this study, we examined patterns of black spruce growth and carbon isotopic composition in tree rings in response to climate warming and drying in the boreal forest of interior Alaska. We examined trees at three nested scales: landscape, toposequence, and a subsample of trees within the toposequence. At each scale, we studied the potential effects of differences in microclimate and moisture availability by sampling on northern and southern aspects. We found that black spruce radial growth responded negatively to monthly metrics of temperature at all examined scales, and we examined ∆(13)C responses on a subsample of trees as representative of the wider region. The negative ∆(13)C responses to temperature reveal that black spruce trees are experiencing moisture stress on both northern and southern aspects. Contrary to our expectations, ∆(13)C from trees on the northern aspect exhibited the strongest drought signal. Our results highlight the prominence of drought stress in the boreal forest of interior Alaska. We conclude that if temperatures continue to warm, we can expect drought-induced productivity declines across large regions of the boreal forest, even for trees located in cool and moist landscape positions. © 2015 John Wiley & Sons Ltd.

  17. Biogenic nitric oxide emission from a spruce forest soil in mountainous terrain

    NASA Astrophysics Data System (ADS)

    Falge, Eva; Bargsten, Anika; Behrendt, Thomas; Meixner, Franz X.

    2010-05-01

    The process-based spatial simulation model SVAT-CN was used to estimate biogenic nitric oxide (NO) emission by soils of a Norway spruce forest (Weidenbrunnen) in the Fichtelgebirge, Germany. SVAT-CN core is a combination of a multiple-layer soil water balance model and a multi-layered canopy gas exchange model. The soil modules comprise a flexible hybrid between a layered bucket model and classical basic liquid flow theory. Further soil processes include: heat transport, distribution of transpiration demand proportionally to soil resistance, reduction of leaf physiological parameters with limiting soil moisture. Spruce forest soils usually are characterized by a thick organic layer (raw humus), with the topmost centimetres being the location where most of the biogenic NO is produced. Within individual spruce forest stands the understory might be composed of patches characterized by different species (e.g. Vaccinium myrtillus, Picea abies, Deschampsia caespitosa), and NO production potentials. The effect of soil physical and chemical parameters and understory types on NO emission from the organic layer was investigated in laboratory incubation and fumigation experiments on soils sampled below the various understory covers found at the Weidenbrunnen site. Results from the laboratory experiments were used to parameterize multi-factorial regression models of soil NO emission with respect to its response to soil temperature and moisture. Parameterization of the spatial model SVAT-CN includes horizontal heterogeneity of over- and understory PAI, understory species distribution, soil texture, bulk density, thickness of organic layer. Simulations are run for intensive observations periods of 2007 and 2008 of the EGER (ExchanGE processes in mountainous Regions) project, a late summer/fall and an early summer period, providing estimates for different understory types (young spruce, blueberry, grass, and moss/litter patches). Validation of the model is being carried out at point scale, by comparison with measured soil moisture and temperature data at 12 locations at the Weidenbrunnen site. In addition model output is compared to soil NO emission data from dynamic chambers. Understory type was found to have a strong influence on the magnitude of soil NO emissions, with emissions from blueberry and young spruce one order of magnitude larger than those from grass or moss/litter patches.

  18. Assessing forest damage in high-elevation coniferous forests in Vermont and New Hampshire using Thematic Mapper data

    NASA Technical Reports Server (NTRS)

    Vogelmann, James E.; Rock, Barrett N.

    1988-01-01

    This study evaluates the potential of measuring/mapping forest damage in spruce-fir forests in the Green Mountains of Vermont and White Mountains of New Hampshire using Landsat Thematic Mapper (TM) data. The TM 1.65/0.83-micron (TM5/4) and 2.22/0.83-micron (TM7/4) band ratios were found to correlate well with ground-based measurements of forest damage (a measure of percentage foliar loss) at 11 spruce-fir stands located on Camels Hump, a mountain in northern Vermont. Images using 0.56 and 1.65-micron bands with 1.65/0.83-micron band ratios indicated locations of heavy conifer forest damage. Both 1.65/0.83 and 2.22/0.83-micron band ratios were used to quantify levels of conifer forest damage among individual mountains throughout many of the Green and White Mountains. Damage was found to be consistently higher for the Green than the White Mountains.

  19. Estimating Forest Species Composition Using a Multi-Sensor Approach

    NASA Astrophysics Data System (ADS)

    Wolter, P. T.

    2009-12-01

    The magnitude, duration, and frequency of forest disturbance caused by the spruce budworm and forest tent caterpillar has increased over the last century due to a shift in forest species composition linked to historical fire suppression, forest management, and pesticide application that has fostered the increase in dominance of host tree species. Modeling approaches are currently being used to understand and forecast potential management effects in changing insect disturbance trends. However, detailed forest composition data needed for these efforts is often lacking. Here, we used partial least squares (PLS) regression to integrate satellite sensor data from Landsat, Radarsat-1, and PALSAR, as well as pixel-wise forest structure information derived from SPOT-5 sensor data (Wolter et al. 2009), to estimate species-level forest composition of 12 species required for modeling efforts. C-band Radarsat-1 data and L-band PALSAR data were frequently among the strongest predictors of forest composition. Pixel-level forest structure data were more important for estimating conifer rather than hardwood forest composition. The coefficients of determination for species relative basal area (RBA) ranged from 0.57 (white cedar) to 0.94 (maple) with RMSE of 8.88 to 6.44 % RBA, respectively. Receiver operating characteristic (ROC) curves were used to determine the effective lower limits of usefulness of species RBA estimates which ranged from 5.94 % (jack pine) to 39.41 % (black ash). These estimates were then used to produce a dominant forest species map for the study region with an overall accuracy of 78 %. Most notably, this approach facilitated discrimination of aspen from birch as well as spruce and fir from other conifer species which is crucial for the study of forest tent caterpillar and spruce budworm dynamics, respectively, in the Upper Midwest. Thus, use of PLS regression as a data fusion strategy has proven to be an effective tool for regional characterization of forest composition within spatially heterogeneous forests using large-format satellite sensor data.

  20. SPRUCE Epiphytic Lichen Annual Biomass Growth in Experimental Plots, 2013-2016.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, R.J.; Nelson, P.R.; Jovan, S.

    This data set provides annual biomass growth rates of epiphytic lichen transplants in the SPRUCE experimental plots at the S1 Bog of the Marcell Experimental Forest. Epiphytic lichens (Evernia mesomorpha, a boreal forest indicator species) were collected at S1 Bog outside the experimental enclosures and mounted on Picea mariana branches inside the 10 experimental enclosures and the 2 ambient plots without enclosures using transplant techniques. Lichen transplants were weighed annually, in August of 2013-2016, to measure biomass growth rates as a function of experimental temperature and CO2 treatments.

  1. UHF Radiowave Propagation through Forests

    DTIC Science & Technology

    1984-05-01

    Region Trees Diameter D r2 Frank et al [24] Northeast US Spruce - Fir 1-12" 2.44" 1.00 Roach [54] ’ Allegheny hardwoods 1-12" 2.27" 0.99 Wiant [76...34A Silvicultural Guide for Spruce - Fir , USDA Forest Service General Technical Report NE-6 (1973). 26. A•K. Fury and M.P. Chen, "Scattering from a... Appalachian hardwoods 4-15" 2.44" 0.99 2-8 DI . • • • Z ,,,¢, :..••.•,,, ,:•; ,., ,,,.. .. empirical density function exceeds that of the normal density

  2. Sensitivity of managed boreal forests in Finland to climate change, with implications for adaptive management.

    PubMed

    Kellomäki, Seppo; Peltola, Heli; Nuutinen, Tuula; Korhonen, Kari T; Strandman, Harri

    2008-07-12

    This study investigated the sensitivity of managed boreal forests to climate change, with consequent needs to adapt the management to climate change. Model simulations representing the Finnish territory between 60 and 70 degrees N showed that climate change may substantially change the dynamics of managed boreal forests in northern Europe. This is especially probable at the northern and southern edges of this forest zone. In the north, forest growth may increase, but the special features of northern forests may be diminished. In the south, climate change may create a suboptimal environment for Norway spruce. Dominance of Scots pine may increase on less fertile sites currently occupied by Norway spruce. Birches may compete with Scots pine even in these sites and the dominance of birches may increase. These changes may reduce the total forest growth locally but, over the whole of Finland, total forest growth may increase by 44%, with an increase of 82% in the potential cutting drain. The choice of appropriate species and reduced rotation length may sustain the productivity of forest land under climate change.

  3. Maine's forests 2008

    Treesearch

    George L. McCaskill; William H. McWilliams; Charles J. Barnett; Brett J. Butler; Mark A. Hatfield; Cassandra M. Kurtz; Randall S. Morin; W. Keith Moser; Charles H. Perry; Christopher W. Woodall

    2011-01-01

    The second annual inventory of Maine's forests was completed in 2008 after more than 3,160 forested plots were measured. Forest land occupies almost 17.7 million acres, which represents 82 percent of the total land area of Maine. The dominant forest-type groups are maple/beech/yellow birch, spruce/fir, white/red/jack pine, and aspen/white birch. Statewide volume...

  4. Multi-sensor data fusion for estimating forest species composition and abundance in northern Minnesota

    Treesearch

    Peter P. Wolter; Phillip A. Townsend

    2011-01-01

    The magnitude, duration, and frequency of forest disturbance caused by the spruce budworm and forest tent caterpillar in northern Minnesota and neighboring Ontario, Canada have increased over the last century due to a shift in forest species composition linked to historical fire suppression, forest management, and pesticide application that has fostered increased...

  5. Wetfall deposition and precipitation chemistry for a central Appalachian forest

    Treesearch

    Frank S. Gilliam; Mary Beth Adams

    1996-01-01

    Although extensive research on acidic deposition has been directed toward spruce-fir forests, less research has been done on the impacts of air pollution on eastern montane hardwood forests. The purpose of this study was to describe precipitation chemistry for several Appalachian hardwood forest sites at or near the Fernow Experimental Forest (FEF) to assess the...

  6. Landscape host abundance and configuration regulate periodic outbreak behavior in spruce budworm Choristoneura fumiferana

    Treesearch

    Louis-Etienne Robert; Brian R. Sturtevant; Barry J. Cooke; Patrick M. A. James; Marie-Josée Fortin; Philip A. Townsend; Peter T. Wolter; Daniel Kneeshaw

    2018-01-01

    Landscape-level forest management has long been hypothesized to affect forest insect outbreak dynamics, but empirical evidence remains elusive. We hypothesized that the combination of increased hardwood relative to host tree species, prevalence of younger forests, and fragmentation of those forests due to forest harvesting legacies would reduce outbreak intensity,...

  7. Chapter 6: Creating a basis for watershed management in high elevation forests

    Treesearch

    Gerald J. Gottfried; Leonard F. DeBano; Peter F. Ffolliott

    1999-01-01

    Higher mountains and plateaus in the Central Arizona Highlands generally support southwestern mixed conifer forests, associated aspen and spruce-fir forests, and a small acreage of grasslands interspersed among the forested areas. Most of the major rivers in the region originate on headwater watersheds that support mixed conifer forests where annual precipitation,...

  8. Influence of fire frequency on carbon consumption in Alaskan blackspruce forests

    NASA Astrophysics Data System (ADS)

    Hoy, E.; Kasischke, E. S.

    2014-12-01

    Increasing temperatures and drier conditions within the boreal forests of Alaska have resulted in increases in burned area and fire frequency, which alter carbon storage and emissions. In particular, analyses of satellite remote sensing data showed that >20% of the area impacted by fires in interior Alaska occurred in areas that had previously burned since 1950 (e.g., short to intermediate interval fires). Field studies showed that in immature black spruce forests ~ 35 to 55 years old organic layers experienced deep burning regardless of topographic position or seasonality of burning, factors that control depth of burning in mature black spruce forests. Here, refinements were made to a carbon consumption model to account for variations in fuel loads and fraction of carbon consumed associated with fire frequency based on quantifying burned area in recently burned sites using satellite imagery. An immature black spruce (Picea mariana) fuel type (including stands of ~0-50 years) was developed which contains new ground-layer carbon consumption values in order to more accurately account for differences between various age classes of black spruce forest. Both versions of the model were used to assess carbon consumption during 100 fire events (over 4.4 x 10^6 ha of burned area) from two recent ultra-large fire years (2004 and 2005). Using the improved model to better attribute fuel type and consumption resulted in higher ground-layer carbon consumption (4.9% in 2004 and 6.8% in 2005) than previously estimated. These adjustments in ground-layer burning resulted in total carbon consumption within 2004 and 2005 of 63.5 and 42.0 Tg of carbon, respectively. Results from this research could be incorporated into larger scale modeling efforts to better assess changes in the climate-fire-vegetation dynamics in interior Alaskan boreal forests, and to understand the impacts of these changes on carbon consumption and emissions.

  9. Effect of bark beetle (Ips typographus L.) attack on bark VOC emissions of Norway spruce (Picea abies Karst.) trees

    NASA Astrophysics Data System (ADS)

    Ghimire, Rajendra P.; Kivimäenpää, Minna; Blomqvist, Minna; Holopainen, Toini; Lyytikäinen-Saarenmaa, Päivi; Holopainen, Jarmo K.

    2016-02-01

    Climate warming driven storms are evident causes for an outbreak of the European spruce bark beetle (Ips typographus L.) resulting in the serious destruction of mature Norway spruce (Picea abies Karst.) forests in northern Europe. Conifer species are major sources of biogenic volatile organic compounds (BVOCs) in the boreal zone. Climate relevant BVOC emissions are expected to increase when conifer trees defend against bark beetle attack by monoterpene (MT)-rich resin flow. In this study, BVOC emission rates from the bark surface of beetle-attacked and non-attacked spruce trees were measured from two outbreak areas, Iitti and Lahti in southern Finland, and from one control site at Kuopio in central Finland. Beetle attack increased emissions of total MTs 20-fold at Iitti compared to Kuopio, but decreased the emissions of several sesquiterpenes (SQTs) at Iitti. At the Lahti site, the emission rate of α-pinene was positively correlated with mean trap catch of bark beetles. The responsive individual MTs were tricyclene, α-pinene, camphene, myrcene, limonene, 1,8-cineole and bornyl acetate in both of the outbreak areas. Our results suggest that bark beetle outbreaks affect local BVOC emissions from conifer forests dominated by Norway spruce. Therefore, the impacts of insect outbreaks are worth of consideration to global BVOC emission models.

  10. Size-dependence of tree growth response to drought for Norway spruce and European beech individuals in monospecific and mixed-species stands.

    PubMed

    Ding, H; Pretzsch, H; Schütze, G; Rötzer, T

    2017-09-01

    Climate anomalies have resulted in changing forest productivity, increasing tree mortality in Central and Southern Europe. This has resulted in more severe and frequent ecological disturbances to forest stands. This study analysed the size-dependence of growth response to drought years based on 384 tree individuals of Norway spruce [Picea abies (L.) Karst.] and European beech [Fagus sylvatica ([L.)] in Bavaria, Germany. Samples were collected in both monospecific and mixed-species stands. To quantify the growth response to drought stress, indices for basal area increment, resistance, recovery and resilience were calculated from tree ring measurements of increment cores. Linear mixed models were developed to estimate the influence of drought periods. The results show that ageing-related growth decline is significant in drought years. Drought resilience and resistance decrease significantly with growth size among Norway spruce individuals. Evidence is also provided for robustness in the resilience capacity of European beech during drought stress. Spruce benefits from species mixing with deciduous beech, with over-yielding spruce in pure stands. The importance of the influence of size-dependence within tree growth studies during disturbances is highlighted and should be considered in future studies of disturbances, including drought. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

  11. Phenotypic evidence suggests a possible major-gene element to weevil resistance in Sitka spruce

    Treesearch

    John N. King; René I. Alfaro; Peter Ott; Lara vanAkker

    2012-01-01

    The weevil resistance breeding program against the white pine weevil, Pissodes strobi Peck (Coleoptera: Curculionidae), particularly for Sitka spruce (Picea sitchensis (Bong.) Carr), is arguably one of the most successful pest resistance breeding programs for plantation forest species, and it has done a lot to rehabilitate...

  12. Site-index comparisons for tree species in northern Minnesota.

    Treesearch

    Willard H. Carmean; Alexander Vasilevsky

    1971-01-01

    Presents site-index comparisons for the following forest species in northern Minnesota: quaking aspen, paper birch, basswood, red oak, black ash, jack pine, red pine, white pine, white spruce, black spruce, balsam fir, white-cedar, and tamarack. Shows site-index relationships among these species by using site-index ratios and species-comparison graphs.

  13. Age and size effects on seed productivity of northern black spruce

    Treesearch

    J. N. Viglas; C. D. Brown; J. F. Johnstone

    2013-01-01

    Slow-growing conifers of the northern boreal forest may require several decades to reach reproductive maturity, making them vulnerable to increases in disturbance frequency. Here, we examine the relationship between stand age and seed productivity of black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.) in Yukon Territory and Alaska....

  14. Fire severity mediates climate-driven shifts in understorey community composition of black spruce stands of interior Alaska

    Treesearch

    Emily L. Bernhardt; Teresa N. Hollingsworth; F. Stuart Chapin

    2011-01-01

    Question: How do pre-fire conditions (community composition and environmental characteristics) and climate-driven disturbance characteristics (fire severity) affect post-fire community composition in black spruce stands? Location: Northern boreal forest, interior Alaska. Methods: We compared plant community composition and environmental stand characteristics in 14...

  15. Premature Needle Loss of Spruce

    Treesearch

    Jennifer Juzwik; Joseph G. O Brien

    1990-01-01

    Premature needle loss on white, black and Norway spruce has been observed in forest plantations in Wisconsin and Minnesota during the past six years. Symptoms vary by species but usually appear first in 2-4-year old needles on lower branches. Infected needles are dropped, resulting in branch mortality that progresses upward through the crown, sometimes killing even...

  16. Red-edge vegetation indices for detecting and assessing disturbances in Norway spruce dominated mountain forests

    NASA Astrophysics Data System (ADS)

    Adamczyk, Joanna; Osberger, Antonia

    2015-05-01

    Here we propose an approach to enhance the detection and assessment of forest disturbances in mountain areas based on red-edge reflectance. The research addresses the need for improved monitoring of areas included in the European Natura 2000 network. Thirty-eight vegetation indices (VI) are assessed for sensitivity to topographic variations. A separability analysis is performed for the resulting set of ten VI whereby two VI (PSSRc2, SR 800/550) are found most suitable for threshold-based OBIA classification. With a correlation analysis (SRCC) between VI and the training samples we identify Datt4 as suitable to represent the magnitude of forest disturbance. The provided information layers illustrate two combined phenomena that were derived by (1) an OBIA delineation and (2) continuous representation of the magnitude of forest disturbance. The satisfactory accuracy assessment results confirm that the approach is useful for operational tasks in the long-term monitoring of Norway spruce dominated forests in mountainous areas, with regard to forest disturbance.

  17. Timber productivity of seven forest ecosystems in southeastern Alaska.

    Treesearch

    Willem W.S. van Hees

    1988-01-01

    Observations of growth on Alaska-cedar (Chamaecyparis nootkatensis), mountain hemlock (Tsuga mertensiana), Sitka spruce (Picea sitchensis), western hemlock (Tsuga heterophylla), and western redcedar (Thuja plicata) on seven forest ecosystems in southeastern Alaska...

  18. AmeriFlux CA-NS6 UCI-1989 burn site

    DOE Data Explorer

    Goulden, Mike [University of California - Irvine

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-NS6 UCI-1989 burn site. Site Description - The UCI-1989 site is located in a continental boreal forest, dominated by black spruce trees, within the BOREAS northern study area in central Manitoba, Canada. The site is a member of a chronological series of sites that are representative secondary succession growth stages after large stand replacement fires. Black spruce trees undergo a slow growth process enabling the accurate determination of the chronosequence of stand age disturbance. Additionally, boreal forests make up approximately 25% of forest ecosystems on earth. With both of these in mind, the UCI sites provide an excellent location to study the CO2 exchange between the atmosphere and boreal forest ecosystems as a function of sequential wildfires.

  19. AmeriFlux CA-NS2 UCI-1930 burn site

    DOE Data Explorer

    Goulden, Mike [University of California - Irvine

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-NS2 UCI-1930 burn site. Site Description - The UCI-1930 site is located in a continental boreal forest, dominated by black spruce trees, within the BOREAS northern study area in central Manitoba, Canada. The site is a member of a chronological series of sites that are representative secondary succession growth stages after large stand replacement fires. Black spruce trees undergo a slow growth process enabling the accurate determination of the chronosequence of stand age disturbance. Additionally, boreal forests make up approximately 25% of forest ecosystems on earth. With both of these in mind, the UCI sites provide an excellent location to study the CO2 exchange between the atmosphere and boreal forest ecosystems as a function of sequential wildfires.

  20. AmeriFlux CA-NS3 UCI-1964 burn site

    DOE Data Explorer

    Goulden, Mike [University of California - Irvine

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-NS3 UCI-1964 burn site. Site Description - The UCI-1964 site is located in a continental boreal forest, dominated by black spruce trees, within the BOREAS northern study area in central Manitoba, Canada. The site is a member of a chronological series of sites that are representative secondary succession growth stages after large stand replacement fires. Black spruce trees undergo a slow growth process enabling the accurate determination of the chronosequence of stand age disturbance. Additionally, boreal forests make up approximately 25% of forest ecosystems on earth. With both of these in mind, the UCI sites provide an excellent location to study the CO2 exchange between the atmosphere and boreal forest ecosystems as a function of sequential wildfires.

  1. AmeriFlux CA-NS7 UCI-1998 burn site

    DOE Data Explorer

    Goulden, Mike [University of California - Irvine

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-NS7 UCI-1998 burn site. Site Description - The UCI-1998 site is located in a continental boreal forest, dominated by black spruce trees, within the BOREAS northern study area in central Manitoba, Canada. The site is a member of a chronological series of sites that are representative secondary succession growth stages after large stand replacement fires. Black spruce trees undergo a slow growth process enabling the accurate determination of the chronosequence of stand age disturbance. Additionally, boreal forests make up approximately 25% of forest ecosystems on earth. With both of these in mind, the UCI sites provide an excellent location to study the CO2 exchange between the atmosphere and boreal forest ecosystems as a function of sequential wildfires.

  2. AmeriFlux CA-NS8 UCI-2003 burn site

    DOE Data Explorer

    Goulden, Mike [University of California - Irvine

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-NS8 UCI-2003 burn site. Site Description - The UCI-2003 site is located in a continental boreal forest, dominated by black spruce trees, within the BOREAS northern study area in central Manitoba, Canada. The site is a member of a chronological series of sites that are representative secondary succession growth stages after large stand replacement fires. Black spruce trees undergo a slow growth process enabling the accurate determination of the chronosequence of stand age disturbance. Additionally, boreal forests make up approximately 25% of forest ecosystems on earth. With both of these in mind, the UCI sites provide an excellent location to study the CO2 exchange between the atmosphere and boreal forest ecosystems as a function of sequential wildfires.

  3. AmeriFlux CA-NS5 UCI-1981 burn site

    DOE Data Explorer

    Goulden, Mike [University of California - Irvine

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-NS5 UCI-1981 burn site. Site Description - The UCI-1981 site is located in a continental boreal forest, dominated by black spruce trees, within the BOREAS northern study area in central Manitoba, Canada. The site is a member of a chronological series of sites that are representative secondary succession growth stages after large stand replacement fires. Black spruce trees undergo a slow growth process enabling the accurate determination of the chronosequence of stand age disturbance. Additionally, boreal forests make up approximately 25% of forest ecosystems on earth. With both of these in mind, the UCI sites provide an excellent location to study the CO2 exchange between the atmosphere and boreal forest ecosystems as a function of sequential wildfires.

  4. AmeriFlux CA-NS4 UCI-1964 burn site wet

    DOE Data Explorer

    Goulden, Mike [University of California - Irvine

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-NS4 UCI-1964 burn site wet. Site Description - The UCI-1964 wet site is located in a continental boreal forest, dominated by black spruce trees, within the BOREAS northern study area in central Manitoba, Canada. The site is a member of a chronological series of sites that are representative secondary succession growth stages after large stand replacement fires. Black spruce trees undergo a slow growth process enabling the accurate determination of the chronosequence of stand age disturbance. Additionally, boreal forests make up approximately 25% of forest ecosystems on earth. With both of these in mind, the UCI sites provide an excellent location to study the CO2 exchange between the atmosphere and boreal forest ecosystems as a function of sequential wildfires.

  5. AmeriFlux CA-NS1 UCI-1850 burn site

    DOE Data Explorer

    Goulden, Mike [University of California - Irvine

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-NS1 UCI-1850 burn site. Site Description - The UCI-1850 site is located in a continental boreal forest, dominated by black spruce trees, within the BOREAS northern study area in central Manitoba, Canada. The site is a member of a chronological series of sites that are representative secondary succession growth stages after large stand replacement fires. Black spruce trees undergo a slow growth process enabling the accurate determination of the chronosequence of stand age disturbance. Additionally, boreal forests make up approximately 25% of forest ecosystems on earth. With both of these in mind, the UCI sites provide an excellent location to study the CO2 exchange between the atmosphere and boreal forest ecosystems as a function of sequential wildfires.

  6. Production of ectomycorrhizal mycelium peaks during canopy closure in Norway spruce forests.

    PubMed

    Wallander, Håkan; Johansson, Ulf; Sterkenburg, Erica; Brandström Durling, Mikael; Lindahl, Björn D

    2010-09-01

    *Here, species composition and biomass production of actively growing ectomycorrhizal (EM) mycelia were studied over the rotation period of managed Norway spruce (Picea abies) stands in south-western Sweden. *The EM mycelia were collected using ingrowth mesh bags incubated in the forest soil during one growing season. Fungal biomass was estimated by ergosterol analysis and the EM species were identified by 454 sequencing of internal transcribed spacer (ITS) amplicons. Nutrient availability and the fungal biomass in soil samples were also estimated. *Biomass production peaked in young stands (10-30 yr old) before the first thinning phase. Tylospora fibrillosa dominated the EM community, especially in these young stands, where it constituted 80% of the EM amplicons derived from the mesh bags. Species richness increased in older stands. *The establishment of EM mycelial networks in young Norway spruce stands requires large amounts of carbon, while much less is needed to sustain the EM community in older stands. The variation in EM biomass production over the rotation period has implications for carbon sequestration rates in forest soils.

  7. Climate change in Canadian forests: Effect of global warming and CO2 fertilization on natural populations of black and white spruce

    NASA Astrophysics Data System (ADS)

    Nelson, E. A.; Thomas, S. C.

    2007-12-01

    Global increases in temperature and atmospheric CO2 concentration are predicted to enhance tree growth in the short term, but studies of current impacts of climate change on Canada's forests are limited. This study examined the effects of increasing temperature and atmospheric CO2 concentration on tree ring growth in west-central Manitoba and northern Ontario, sampling white spruce (Picea glauca) and black spruce (Picea mariana), respectively. Over 50 tree cores from each site were sampled, analysed for ring-width, cross-dated and detrended, generating a ~100 y chronology for each population. We found a positive correlation between ring-width increment and spring temperatures (April-May: p<0.005) in Ontario. In Manitoba, however, we found a negative correlation between summer temperatures (Jul-Aug: p<0.005) and ring-width increment coincident with a positive relationship with summer precipitation (July: p<0.03). We examined the residuals following a regression with temperature for a positive trend over time, which has been interpreted in prior studies as evidence for a CO2 fertilization effect. We detected no such putative CO2 fertilization signal in either spruce population. Our results suggest that temperature-limited lowland black spruce communities may respond positively to moderate warming, but that water-limited upland white spruce communities may suffer from drought stress under high temperature conditions. Neither population appears to benefit from increasing CO2 availability.

  8. Spatial distribution of Qinghai spruce forests and the thresholds of influencing factors in a small catchment, Qilian Mountains, northwest China.

    PubMed

    Yang, Wenjuan; Wang, Yanhui; Wang, Shunli; Webb, Ashley A; Yu, Pengtao; Liu, Xiande; Zhang, Xuelong

    2017-07-17

    Forest restoration in dryland mountainous areas is extremely difficult due to dry climate, complex topography and accelerating climate change. Thus, exact identification of suitable sites is required. This study at a small watershed of Qilian Mountains, Northwest China, aimed to determine the important factors and their thresholds limiting the spatial distribution of forests of Qinghai spruce (Picea crassifolia), a locally dominant tree species. The watershed was divided into 342 spatial units. Their location, terrain and vegetation characteristics were recorded. Statistical analysis showed that the potential distribution area of Qinghai spruce forests is within an ellipse with the axes of elevation (from 2673.6 to 3202.2 m a.s.l.) and slope aspect (from -162.1° to 75.1° deviated from North). Within this ellipse, the forested sites have a soil thickness ≥40 cm, and slope positions of lower-slope, lower- or middle-slope, anywhere if the elevation is <2800, 2800-2900, >2900 m a.s.l, respectively. The corresponding mean annual air temperature at upper elevation boundary is -2.69 °C, while the mean annual precipitation at lower elevation boundary is 374 (331) mm within the small watershed (study area). The high prediction accuracy using these 4 factors can help to identify suitable sites and increase the success of afforestation.

  9. Cloud immersion alters microclimate, photosynthesis and water relations in Rhododendron catawbiense and Abies fraseri seedlings in the southern Appalachian Mountains, USA.

    PubMed

    Johnson, Daniel M; Smith, William K

    2008-03-01

    The high altitude spruce-fir (Abies fraseri (Pursh) Poiret.-Picea rubens Sarg.) forests of the southern Appalachian Mountains, USA, experience frequent cloud immersion. Recent studies indicate that cloud bases may have risen over the past 30 years, resulting in less frequent forest cloud immersion, and that further increases in cloud base height are likely in the event of continued climate warming. To assess the impact of this trend on the regeneration of high altitude spruce-fir forests and the migration of plant communities, in particular the encroachment of spruce-fir forests and Rhododendron catawbiense Michx. islands into adjacent grass bald communities, we investigated effects of cloud immersion on photosynthetic parameters of seedlings of Abies fraseri and R. catawbiense in a grass bald site and A. fraseri in a forest understory. Although photosynthetic photon flux was 4.2 to 19.4-fold greater during clear conditions, cloud immersion had no effect on photosynthesis in A. fraseri at either site, whereas it reduced photosynthesis of R. catawbiense by about 40%. However, cloud immersion increased mean leaf fluorescence by 7.1 to 12.8% in both species at both sites. Cloud immersion increased mean relative humidity from 65 to 96%, reduced transpiration by 95% and reduced mean leaf-to-air temperature difference from 6.6 to 0.5 degrees C.

  10. Time since death and decay rate constants of Norway spruce and European larch deadwood in subalpine forests determined using dendrochronology and radiocarbon dating

    NASA Astrophysics Data System (ADS)

    Petrillo, M.; Cherubini, P.; Fravolini, G.; Ascher, J.; Schärer, M.; Synal, H.-A.; Bertoldi, D.; Camin, F.; Larcher, R.; Egli, M.

    2015-09-01

    Due to the large size and highly heterogeneous spatial distribution of deadwood, the time scales involved in the coarse woody debris (CWD) decay of Picea abies (L.) Karst. and Larix decidua Mill. in Alpine forests have been poorly investigated and are largely unknown. We investigated the CWD decay dynamics in an Alpine valley in Italy using the five-decay class system commonly employed for forest surveys, based on a macromorphological and visual assessment. For the decay classes 1 to 3, most of the dendrochronological samples were cross-dated to assess the time that had elapsed since tree death, but for decay classes 4 and 5 (poorly preserved tree rings) and some others not having enough tree rings, radiocarbon dating was used. In addition, density, cellulose and lignin data were measured for the dated CWD. The decay rate constants for spruce and larch were estimated on the basis of the density loss using a single negative exponential model. In the decay classes 1 to 3, the ages of the CWD were similar varying between 1 and 54 years for spruce and 3 and 40 years for larch with no significant differences between the classes; classes 1-3 are therefore not indicative for deadwood age. We found, however, distinct tree species-specific differences in decay classes 4 and 5, with larch CWD reaching an average age of 210 years in class 5 and spruce only 77 years. The mean CWD rate constants were 0.012 to 0.018 yr-1 for spruce and 0.005 to 0.012 yr-1 for larch. Cellulose and lignin time trends half-lives (using a multiple-exponential model) could be derived on the basis of the ages of the CWD. The half-lives for cellulose were 21 yr for spruce and 50 yr for larch. The half-life of lignin is considerably higher and may be more than 100 years in larch CWD.

  11. Persistent Effects of Fire Severity on Early Successional Forests in Interior Alaska

    NASA Technical Reports Server (NTRS)

    Shenoy, Aditi; Johnstone, Jill F.; Kasischke, Eric S.; Kielland, Knut

    2011-01-01

    There has been a recent increase in the frequency and extent of wildfires in interior Alaska, and this trend is predicted to continue under a warming climate. Although less well documented, corresponding increases in fire severity are expected. Previous research from boreal forests in Alaska and western Canada indicate that severe fire promotes the recruitment of deciduous tree species and decreases the relative abundance of black spruce (Picea mariana) immediately after fire. Here we extend these observations by (1) examining changes in patterns of aspen and spruce density and biomass that occurred during the first two decades of post-fire succession, and (2) comparing patterns of tree composition in relation to variations in post-fire organic layer depth in four burned black spruce forests in interior Alaska after 10-20 years of succession.Wefound that initial effects of fire severity on recruitment and establishment of aspen and black spruce were maintained by subsequent effects of organic layer depth and initial plant biomass on plant growth during post-fire succession. The proportional contribution of aspen (Populus tremuloides) to total stand biomass remained above 90% during the first and second decades of succession in severely burned sites, while in lightly burned sites the proportional contribution of aspen was reduced due to a 40- fold increase in spruce biomass in these sites. Relationships between organic layer depth and stem density and biomass were consistently negative for aspen, and positive or neutral for black spruce in all four burns. Our results suggest that initial effects of post-fire organic layer depths on deciduous recruitment are likely to translate into a prolonged phase of deciduous dominance during post-fire succession in severely burned stands. This shift in vegetation distribution has important implications for climate-albedo feedbacks, future fire regime, wildlife habitat quality and natural resources for indigenous subsistence activities in interior Alaska.

  12. Silver fir and Douglas fir are more tolerant to extreme droughts than Norway spruce in south-western Germany.

    PubMed

    Vitali, Valentina; Büntgen, Ulf; Bauhus, Jürgen

    2017-12-01

    Improving our understanding of the potential of forest adaptation is an urgent task in the light of predicted climate change. Long-term alternatives for susceptible yet economically important tree species such as Norway spruce (Picea abies) are required, if the frequency and intensity of summer droughts will continue to increase. Although Silver fir (Abies alba) and Douglas fir (Pseudotsuga menziesii) have both been described as drought-tolerant species, our understanding of their growth responses to drought extremes is still limited. Here, we use a dendroecological approach to assess the resistance, resilience, and recovery of these important central Europe to conifer species the exceptional droughts in 1976 and 2003. A total of 270 trees per species were sampled in 18 managed mixed-species stands along an altitudinal gradient (400-1200 m a.s.l.) at the western slopes of the southern and central Black Forest in southwest Germany. While radial growth in all species responded similarly to the 1976 drought, Norway spruce was least resistant and resilient to the 2003 summer drought. Silver fir showed the overall highest resistance to drought, similarly to Douglas fir, which exhibited the widest growth rings. Silver fir trees from lower elevations were more drought prone than trees at higher elevations. Douglas fir and Norway spruce, however, revealed lower drought resilience at higher altitudes. Although the 1976 and 2003 drought extremes were quite different, Douglas fir maintained consistently the highest radial growth. Although our study did not examine population-level responses, it clearly indicates that Silver fir and Douglas fir are generally more resistant and resilient to previous drought extremes and are therefore suitable alternatives to Norway spruce; Silver fir more so at higher altitudes. Cultivating these species instead of Norway spruce will contribute to maintaining a high level of productivity across many Central European mountain forests under future climate change. © 2017 John Wiley & Sons Ltd.

  13. Acidic deposition, cation mobilization, and biochemical indicators of stress in healthy red spruce

    USGS Publications Warehouse

    Shortle, W.C.; Smith, K.T.; Minocha, R.; Lawrence, G.B.; David, M.B.

    1997-01-01

    Dendrochemical and biochemical markers link stress in apparently healthy red spruce trees (Picea rubens) to acidic deposition. Acidic deposition to spruce forests of the northeastern USA increased sharply during the 1960s. Previous reports related visible damage of trees at high elevations to root and soil processes. In this report, dendrochemical and foliar biochemical markers indicate perturbations in biological processes in healthy red spruce trees across the northeastern USA. Previous research on the dendrochemistry of red spruce stemwood indicated that under uniform environmental conditions, stemwood concentrations of Ca and Mg decreased with increasing radial distance from the pith. For nine forest locations, frequency analysis shows that 28 and 52% of samples of red spruce stemwood formed in the 1960s are enriched in Ca and Mg, respectively, relative to wood formed prior to and after the 1960s. This enrichment in trees throughout the northeastern USA may be interpretable as a signal of increased availability of essential cations in forest soils. Such a temporary increase in the availability of Ca and Mg could be caused by cation mobilization, a consequence of increased acidic deposition. During cation mobilization, essential Ca and Mg as well as potentially harmful Al become more available for interaction with binding sites in the soil and absorbing roots. As conditions which favor cation mobilization continue, Ca and Mg can be leached or displaced from the soil. A measure of the interaction between Ca and Al is the Al/Ca binding ratio (molar charge ratio of exchangeable Al to exchangeable Ca). As the Al/Ca binding ratio in the root zone increased from 0.3 to 1.9, the foliar concentration of the biochemical stress marker putrescine also increased from 45 to 145 nm g-1. The correlation of the putrescine concentration to the Al/Ca binding ratio (adj. r2 = 0.68, P < 0.027) suggests that foliar stress may be linked to soil chemistry.

  14. Wildlife of southern forests habitat & management (Chapter 4): Defining the Forests

    Treesearch

    James G. Dickson; Raymond M. Sheffield

    2003-01-01

    Forests of the South are very diverse and productive. Included among southern forests are the boreal spruce- fir forests of the highest mountain peaks of the Blue Ridge Mountains to the lowest bottomland hardwoods on flood-deposited soil with elevations near sea level. In between are the diverse upland hardwood stands in northerly mountainous areas of the South and...

  15. Changes in forest soils as the result of exotic diseases, timber harvest, and fire exclusion and their implications on forest restoration

    Treesearch

    Russell T. Graham; Theresa B. Jain

    2007-01-01

    In the western United States and throughout the world, three general classes of coniferous forests can be identified with each having similar vegetative complexes, native disturbances, and climate (Daubenmire and Daubenmire 1968, Hann et al. 1997). Dry forests, often dominated by pines (Pinus), cold forests often dominated by spruces (Picea...

  16. Expression of the β-glucosidase gene Pgβglu-1 underpins natural resistance of white spruce against spruce budworm

    PubMed Central

    Mageroy, Melissa H; Parent, Geneviève; Germanos, Gaby; Giguère, Isabelle; Delvas, Nathalie; Maaroufi, Halim; Bauce, Éric; Bohlmann, Joerg; Mackay, John J

    2015-01-01

    Periodic outbreaks of spruce budworm (SBW) affect large areas of ecologically and economically important conifer forests in North America, causing tree mortality and reduced forest productivity. Host resistance against SBW has been linked to growth phenology and the chemical composition of foliage, but the underlying molecular mechanisms and population variation are largely unknown. Using a genomics approach, we discovered a β-glucosidase gene, Pgβglu-1, whose expression levels and function underpin natural resistance to SBW in mature white spruce (Picea glauca) trees. In phenotypically resistant trees, Pgβglu-1 transcripts were up to 1000 times more abundant than in non-resistant trees and were highly enriched in foliage. The encoded PgβGLU-1 enzyme catalysed the cleavage of acetophenone sugar conjugates to release the aglycons piceol and pungenol. These aglycons were previously shown to be active against SBW. Levels of Pgβglu-1 transcripts and biologically active acetophenone aglycons were substantially different between resistant and non-resistant trees over time, were positively correlated with each other and were highly variable in a natural white spruce population. These results suggest that expression of Pgβglu-1 and accumulation of acetophenone aglycons is a constitutive defence mechanism in white spruce. The progeny of resistant trees had higher Pgβglu-1 gene expression than non-resistant progeny, indicating that the trait is heritable. With reported increases in the intensity of SBW outbreaks, influenced by climate, variation of Pgβglu-1 transcript expression, PgβGLU-1 enzyme activity and acetophenone accumulation may serve as resistance markers to better predict impacts of SBW in both managed and wild spruce populations. PMID:25302566

  17. Biogeochemistry and plant physiological traits interact to reinforce patterns of post-fire dominance in boreal forests

    NASA Astrophysics Data System (ADS)

    Shenoy, A.; Kielland, K.; Johnstone, J. F.

    2011-12-01

    Increases in the frequency, extent, and severity of fire in the North American boreal region are projected to continue under a warming climate and are likely to be associated with changes in future vegetation composition. In interior Alaska, fire severity is linked to the relative dominance of deciduous versus coniferous canopy species. Severely burned areas have high levels of deciduous recruitment and subsequent stand dominance, while lightly burned areas exhibit black spruce self-replacement. To elucidate potential mechanisms by which differential fire severity results in differential post-fire vegetation development, we examined changes in soil nitrogen (N) supply (NO3- and NH4+) and in situ 15N uptake by young aspen (Populus tremuloides) and black spruce (Picea mariana) trees growing in lightly and severely burned areas. We hypothesized that (a) soil nitrate supply would be higher in severely burned sites and (b) since conifers have been shown to have a reduced physiological capacity for NO3- uptake, aspen would display greater rates of NO3- uptake than spruce in severely burned sites. Our results suggested that the composition and magnitude of inorganic N supply 14 years after the fire was nearly identical in high-severity and low-severity sites, and nitrate represented nearly 50% of the supply. However, both aspen and spruce took up substantially more NH4+-N than NO3- -N regardless of fire severity. Surprisingly, spruce exhibited only a moderately lower rate of NO3- uptake (μg N/g root-1h-1) than aspen. At the stand level, aspen took up nearly an order-of-magnitude more N per hectare in severely burned sites compared to lightly burned sites, while spruce exhibited the opposite pattern of N uptake with respect to fire severity. Whereas ammonium appeared to be preferred by both species, nitrate represented a larger component of N uptake (based on the NO3-:NH4+ uptake ratio) in aspen (0.7) than in spruce (0.4). We suggest that these species-specific differences in N preference coupled with their respective physiological response to fire severity represent a positive feedback loop that reinforce the opposing stand dominance patterns that have developed at the two ends of the fire severity spectrum. Shifts in forest composition from the current dominance by conifers to a future landscape dominated by deciduous forest are of concern due to impacts on climate-albedo feedbacks, forest productivity, ecosystem carbon storage, and wildlife habitat use.

  18. Survival of Norway spruce remains higher in mixed stands under a dryer and warmer climate.

    PubMed

    Neuner, Susanne; Albrecht, Axel; Cullmann, Dominik; Engels, Friedrich; Griess, Verena C; Hahn, W Andreas; Hanewinkel, Marc; Härtl, Fabian; Kölling, Christian; Staupendahl, Kai; Knoke, Thomas

    2015-02-01

    Shifts in tree species distributions caused by climatic change are expected to cause severe losses in the economic value of European forestland. However, this projection disregards potential adaptation options such as tree species conversion, shorter production periods, or establishment of mixed species forests. The effect of tree species mixture has, as yet, not been quantitatively investigated for its potential to mitigate future increases in production risks. For the first time, we use survival time analysis to assess the effects of climate, species mixture and soil condition on survival probabilities for Norway spruce and European beech. Accelerated Failure Time (AFT) models based on an extensive dataset of almost 65,000 trees from the European Forest Damage Survey (FDS)--part of the European-wide Level I monitoring network--predicted a 24% decrease in survival probability for Norway spruce in pure stands at age 120 when unfavorable changes in climate conditions were assumed. Increasing species admixture greatly reduced the negative effects of unfavorable climate conditions, resulting in a decline in survival probabilities of only 7%. We conclude that future studies of forest management under climate change as well as forest policy measures need to take this, as yet unconsidered, strongly advantageous effect of tree species mixture into account. © 2014 John Wiley & Sons Ltd.

  19. Mapping of taiga forest units using AIRSAR data and/or optical data, and retrieval of forest parameters

    NASA Technical Reports Server (NTRS)

    Rignot, Eric; Williams, Cynthia; Way, Jobea; Viereck, Leslie

    1993-01-01

    A maximum a posteriori Bayesian classifier for multifrequency polarimetric SAR data is used to perform a supervised classification of forest types in the floodplains of Alaska. The image classes include white spruce, balsam poplar, black spruce, alder, non-forests, and open water. The authors investigate the effect on classification accuracy of changing environmental conditions, and of frequency and polarization of the signal. The highest classification accuracy (86 percent correctly classified forest pixels, and 91 percent overall) is obtained combining L- and C-band frequencies fully polarimetric on a date where the forest is just recovering from flooding. The forest map compares favorably with a vegetation map assembled from digitized aerial photos which took five years for completion, and address the state of the forest in 1978, ignoring subsequent fires, changes in the course of the river, clear-cutting of trees, and tree growth. HV-polarization is the most useful polarization at L- and C-band for classification. C-band VV (ERS-1 mode) and L-band HH (J-ERS-1 mode) alone or combined yield unsatisfactory classification accuracies. Additional data acquired in the winter season during thawed and frozen days yield classification accuracies respectively 20 percent and 30 percent lower due to a greater confusion between conifers and deciduous trees. Data acquired at the peak of flooding in May 1991 also yield classification accuracies 10 percent lower because of dominant trunk-ground interactions which mask out finer differences in radar backscatter between tree species. Combination of several of these dates does not improve classification accuracy. For comparison, panchromatic optical data acquired by SPOT in the summer season of 1991 are used to classify the same area. The classification accuracy (78 percent for the forest types and 90 percent if open water is included) is lower than that obtained with AIRSAR although conifers and deciduous trees are better separated due to the presence of leaves on the deciduous trees. Optical data do not separate black spruce and white spruce as well as SAR data, cannot separate alder from balsam poplar, and are of course limited by the frequent cloud cover in the polar regions. Yet, combining SPOT and AIRSAR offers better chances to identify vegetation types independent of ground truth information using a combination of NDVI indexes from SPOT, biomass numbers from AIRSAR, and a segmentation map from either one.

  20. Evidence of compounded disturbance effects on vegetation recovery following high-severity wildfire and spruce beetle outbreak

    Treesearch

    Amanda R. Carlson; Jason S. Sibold; Timothy J. Assal; Jose F. Negron

    2017-01-01

    Spruce beetle (Dendroctonus rufipennis) outbreaks are rapidly spreading throughout subalpine forests of the Rocky Mountains, raising concerns that altered fuel structures may increase the ecological severity of wildfires. Although many recent studies have found no conclusive link between beetle outbreaks and increased fire size or canopy mortality, few studies have...

  1. Influence of precommercial thinning and herbicides on understory vegetation of young-growth Sitka spruce forest in southeastern Alaska

    Treesearch

    Elizabeth C. Cole; Thomas A. Hanley; Michael Newton

    2010-01-01

    The effects of precommercial thinning on the understory vegetative cover of 16- to 18-year-old spruce-hemlock (Picea sitchensis (Bong.) Carriere--Tsuga heterophylla (Raf.) Sarg.) stands were studied in seven replicate areas over seven growing seasons postthinning. Vegetative cover was analyzed at the class level, but species-...

  2. Photosynthetic characteristics of fagus sylvatica and quercus robur established for stand conversion from picea abies

    Treesearch

    Emile S. Gardiner; Magnus Lof; Joseph J. O' brien; John A. Stanturf; Palle Madsen

    2009-01-01

    Efforts inEurope to convertNorway spruce (Picea abies) plantations to broadleaf ormixed broadleaf-conifer forests could be bolstered by an increased understanding of how artificial regeneration acclimates and functions under a range of Norway spruce stand conditions. We studied foliage characteristics and leaflevel photosynthesis on 7-year-old European beech (Fagus...

  3. Putrescine: a marker of stress in red spruce trees

    Treesearch

    Rakesh Minocha; Walter C. Shortle; Gregory B. Lawrence; B. David Mark; Subhash C. Minocha

    1996-01-01

    Aluminum (Al) has been suggested to be an important stress factor in forest decline due to its mobilization in soil following atmospheric deposition of acidic pollutants. A major goal of our research is to develop physiological and biochemical markers of stress in trees using cell cultures and whole plants. Needles of red spruce (Picea rubens)...

  4. Carbon flux to woody tissues in a beech/spruce forest during summer and in response to chronic O3 exposure

    EPA Science Inventory

    The present study compares the dynamics in carbon (C) allocation of adult deciduous beech (Fagus sylvatica) and evergreen spruce (Picea abies) during summer and in response to seven-year-long exposure with twice-ambient ozone (O3) concentrations (2 × O3). Focus was on the respira...

  5. Photosynthetic characteristics of Fagus sylvatica and Quercus robur established for stand conversion from Picea abies

    Treesearch

    E.S. Gardiner; J.J. O’Brien; M. Löf; J.A. Stanturf; P. Madsen

    2009-01-01

    Efforts in Europe to convertNorway spruce (Picea abies) plantations to broadleaf ormixed broadleaf-conifer forests could be bolstered by an increased understanding of how artificial regeneration acclimates and functions under a range of Norway spruce stand conditions. We studied foliage characteristics and leaflevel photosynthesis on 7-year-old European beech (Fagus...

  6. Animal damage to young spruce and fir in Maine

    Treesearch

    Barton M. Blum

    1977-01-01

    The loss of terminal buds on small balsam fir (Abies balsamea (L.) Mill.) and spruce (Picea spp.) trees because of nipping by mammals or birds has increased on the Penobscot Experimental Forest in recent years. The cut stem is smooth and slightly angled; there is no sign of tearing. Unnipped trees grew about 13 percent more than...

  7. Forest defoliators and climatic change: potential changes in spatial distribution of outbreaks of western spruce budworm (Lepidoptera: Tortricidae) and gypsy moth (Lepidoptera Lymantriidae)

    Treesearch

    David W. ​Williams; Andrew M. Liebhold

    1995-01-01

    Changes in geographical ranges and spatial extent of outbreaks of pest species are likely consequences of climatic change. We investigated potential changes in spatial distribution of outbreaks of western spruce budworm, Choristoneura occidentalis Freeman, and gypsy moth, Lymantria dispar (L.), in Oregon and Pennsylvania,...

  8. Minnesota Forest Resources in 2000.

    Treesearch

    David E. Haugen; Manfred E. Mielke

    2002-01-01

    Results of the 2000 annual inventory of Minnesota show over 16.5 million acres of forest land, over 17.6 billion cubic feet of all live volume on timberland, and an estimated 429 million dry tons of all live aboveground tree biomass on timberland. Known pests in Minnesota forests include the forest tent caterpillar, spruce budworm, large aspen tortrix, and introduced...

  9. Saproxylic and non-saproxylic beetle assemblages in boreal spruce forests of different age and forestry intensity.

    PubMed

    Stenbacka, Fredrik; Hjältén, Joakim; Hilszczański, Jacek; Dynesius, Mats

    2010-12-01

    Current clear-cutting forestry practices affect many boreal organisms negatively, and those dependent on dead wood (saproxylics) are considered as particularly vulnerable. The succession of species assemblages in managed forest habitats regenerating after clear-cutting is, however, poorly known. We compared beetle assemblages in three successional stages of managed boreal spruce forests established after clear-cutting and two types of older spruce forests that had not been clear-cut. We also assessed whether saproxylic and non-saproxylic beetle assemblages show similar biodiversity patterns among these forest types. Beetles were collected in window traps in nine study areas, each encompassing a protected old-growth forest (mean forest age approximately 160 years, mean dead wood volume 34 m3/ha), an unprotected mature forest (approximately 120 years old, 15 m3/ha), a middle-aged commercially thinned forest (53 years old, 3 m3/ha), a young unthinned forest (30 years old, 4 m3/ha), and a clearcut (5-7 years after harvest, 11 m3/ha). Saproxylic beetles, in particular red-listed species, were more abundant and more species rich in older forest types, whereas no significant differences among forest types in these variables were detected for non-saproxylics. The saproxylic assemblages were clearly differentiated; with increasing forest age, assemblage compositions gradually became more similar to those of protected old-growth forests, but the assemblage composition in thinned forests could not be statistically distinguished from those of the two oldest forest types. Many saproxylic beetles adapted to late-successional stages were present in thinned middle-aged forests but absent from younger unthinned forests. In contrast, non-saproxylics were generally more evenly distributed among the five forest types, and the assemblages were mainly differentiated between clearcuts and forested habitats. The saproxylic beetle assemblages of unprotected mature forests were very similar to those of protected old-growth forests. This indicates a relatively high conservation value of mature boreal forests currently subjected to clear-cutting and raises the question of whether future mature forests will have the same qualities. Our results suggest a high beetle conservation potential of developing managed forests, provided that sufficient amounts and qualities of dead wood are made available (e.g., during thinning operations). Confirming studies of beetle reproduction in dead wood introduced during thinning are, however, lacking.

  10. Severely insect-damaged forest: A temporary trap for red squirrels?

    Treesearch

    Claire A. Zugmeyer; John L. Koprowski

    2009-01-01

    Recent insect infestations in the spruce-fir forest in the Pinalenno Mountains of southeastern Arizona provided an opportunity to document response to severe forest disturbance and existence of an ecological trap for an endemic montane isolate, the endangered Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamensis). From September 2003 to...

  11. Greenery - an opportunity for forest landowners

    Treesearch

    A.L. Hammett; J.L. Chamberlain

    2002-01-01

    For generations, materials gathered from American forests have been used for holiday decorations and floral arrangements including Christmas wreaths, roping, swags, and sprays. Forest species utilized for these products include Fraser fir, Norway and blue spruce, mountain laurel, boxwood, ivy, grape vine, juniper, Douglas fir, incense cedar, and holly. White pine (...

  12. Sphagnum mosses limit total carbon consumption during fire in Alaskan black spruce forests

    Treesearch

    G. Shetler; .R. Turetsky; E. Kane; E. Kasischke

    2008-01-01

    The high water retention of hummock-forming Sphagnum species minimizes soil moisture fluctuations and might protect forest floor organic matter from burning during wildfire. We hypothesized that Sphagnum cover reduces overall forest floor organic matter consumption during wildfire compared with other ground-layer vegetation. We...

  13. Northern forests, Chapter 7

    Treesearch

    L.H. Pardo; C.L. Goodale; E.A. Lilleskov; L.H. Geiser

    2011-01-01

    The Northern Forests ecological region spans much of Canada, from Saskatchewan to Newfoundland; its southern portion extends into the northern United States (CEC 1997). The U.S. component includes the northern hardwood and spruce-fir forest types and encompasses parts of the Northeast (mountainous regions in Pennsylvania, New York, New Jersey, Connecticut,...

  14. Effects of vegetation type on microbial biomass carbon and nitrogen in subalpine mountain forest soils.

    PubMed

    Ravindran, Anita; Yang, Shang-Shyng

    2015-08-01

    Microbial biomass plays an important role in nutrient transformation and conservation of forest and grassland ecosystems. The objective of this study was to determine the microbial biomass among three vegetation types in subalpine mountain forest soils of Taiwan. Tatachia is a typical high-altitude subalpine temperate forest ecosystem in Taiwan with an elevation of 1800-3952 m and consists of three vegetation types: spruce, hemlock, and grassland. Three plots were selected in each vegetation type. Soil samples were collected from the organic layer, topsoil, and subsoil. Microbial biomass carbon (Cmic) was determined by the chloroform fumigation-extraction method, and microbial biomass nitrogen (Nmic) was determined from the total nitrogen (Ntot) released during fumigation-extraction. Bacteria, actinomycetes, fungi, cellulolytic microbes, phosphate-solubilizing microbes, and nitrogen-fixing microbes were also counted. The Cmic and Nmic were highest in the surface soil and declined with the soil depth. These were also highest in spruce soils, followed by in hemlock soils, and were lowest in grassland soils. Cmic and Nmic had the highest values in the spring season and the lowest values in the winter season. Cmic and Nmic had significantly positive correlations with total organic carbon (Corg) and Ntot. Contributions of Cmic and Nmic, respectively, to Corg and Ntot indicated that the microbial biomass was immobilized more in spruce and hemlock soils than in grassland soils. Microbial populations of the tested vegetation types decreased with increasing soil depth. Cmic and Nmic were high in the organic layer and decreased with the depth of layers. These values were higher for spruce and hemlock soils than for grassland soils. Positive correlations were observed between Cmic and Nmic and between Corg and Ntot. Copyright © 2014. Published by Elsevier B.V.

  15. Forest biomass carbon stocks and variation in Tibet's carbon-dense forests from 2001 to 2050.

    PubMed

    Sun, Xiangyang; Wang, Genxu; Huang, Mei; Chang, Ruiying; Ran, Fei

    2016-10-05

    Tibet's forests, in contrast to China's other forests, are characterized by primary forests, high carbon (C) density and less anthropogenic disturbance, and they function as an important carbon pool in China. Using the biomass C density data from 413 forest inventory sites and a spatial forest age map, we developed an allometric equation for the forest biomass C density and forest age to assess the spatial biomass C stocks and variation in Tibet's forests from 2001 to 2050. The results indicated that the forest biomass C stock would increase from 831.1 Tg C in 2001 to 969.4 Tg C in 2050, with a net C gain of 3.6 Tg C yr -1 between 2001 and 2010 and a decrease of 1.9 Tg C yr -1 between 2040 and 2050. Carbon tends to allocate more in the roots of fir forests and less in the roots of spruce and pine forests with increasing stand age. The increase of the biomass carbon pool does not promote significant augmentation of the soil carbon pool. Our findings suggest that Tibet's mature forests will remain a persistent C sink until 2050. However, afforestation or reforestation, especially with the larger carbon sink potential forest types, such as fir and spruce, should be carried out to maintain the high C sink capacity.

  16. Forest biomass carbon stocks and variation in Tibet’s carbon-dense forests from 2001 to 2050

    PubMed Central

    Sun, Xiangyang; Wang, Genxu; Huang, Mei; Chang, Ruiying; Ran, Fei

    2016-01-01

    Tibet’s forests, in contrast to China’s other forests, are characterized by primary forests, high carbon (C) density and less anthropogenic disturbance, and they function as an important carbon pool in China. Using the biomass C density data from 413 forest inventory sites and a spatial forest age map, we developed an allometric equation for the forest biomass C density and forest age to assess the spatial biomass C stocks and variation in Tibet’s forests from 2001 to 2050. The results indicated that the forest biomass C stock would increase from 831.1 Tg C in 2001 to 969.4 Tg C in 2050, with a net C gain of 3.6 Tg C yr−1 between 2001 and 2010 and a decrease of 1.9 Tg C yr−1 between 2040 and 2050. Carbon tends to allocate more in the roots of fir forests and less in the roots of spruce and pine forests with increasing stand age. The increase of the biomass carbon pool does not promote significant augmentation of the soil carbon pool. Our findings suggest that Tibet’s mature forests will remain a persistent C sink until 2050. However, afforestation or reforestation, especially with the larger carbon sink potential forest types, such as fir and spruce, should be carried out to maintain the high C sink capacity. PMID:27703215

  17. Nonlinear responses of white spruce growth to climate variability in interior Alaska

    Treesearch

    A.H. Lloyd; P.A. Duffy; D.H. Mann

    2013-01-01

    Ongoing warming at high latitudes is expected to lead to large changes in the structure and function of boreal forests. Our objective in this research is to determine the climatic controls over the growth of white spruce (Picea glauca (Moench) Voss) at the warmest driest margins of its range in interior Alaska. We then use those relationships to...

  18. Effects of a western spruce budworm outbreak on private lands in eastern Oregon, 1980-1994.

    Treesearch

    David L. Azuma; David L. Overhulser

    2008-01-01

    Forest Inventory and Analysis data from three inventory periods were used to examine the effects of a western spruce budworm outbreak on private lands in eastern Oregon. Growth was negatively related to defoliation with differences between crown ratio and species. The mortality and salvage harvesting caused changes in stand structure on private lands. Although many...

  19. Crown structure and growth efficiency of red spruce in uneven-aged, mixed-species stands in Maine

    Treesearch

    Douglas A. Maguire; John C. Brissette; Lianhong. Gu

    1998-01-01

    Several hypotheses about the relationships among individual tree growth, tree leaf area, and relative tree size or position were tested with red spruce (Picea rubens Sarg.) growing in uneven-aged, mixed-species forests of south-central Maine, U.S.A. Based on data from 65 sample trees, predictive models were developed to (i)...

  20. Estimating potential Engelmann spruce seed production on the Fraser Experimental Forest, Colorado

    Treesearch

    Robert R. Alexander; Carleton B. Edminster; Ross K. Watkins

    1986-01-01

    Two good, three heavy, and two bumper spruce seed crops were produced during a 15-year period. There was considerable variability in seed crops, however. Not all locations produced good to bumper seed crops when overall yearly ratings averaged good or better; conversely, some locations produced bumper seed crops in 3 or more years. Mathematical relationships,...

  1. Silvicultural potential for pre-comercial treatment in northern forest type

    Treesearch

    H. W.,Jr Hocker

    1977-01-01

    It is proposed that pre-commercial thinning of young northern hardwood, oak, white pine and spruce-fir stands be carried out using appropriate stocking guides to regulate stand density. Thinning should be carried out when stands are-between 1" and 2" dbh. Pruning of eastern white pine is recommended, while pruning of spruce and yellow birch seems feasible,...

  2. Recent evolution and divergence among populations of a rare Mexican endemic, Chihuahua spruce, following holocene climatic warming

    Treesearch

    F. Thomas Ledig; Virginia Jacob-Cervantes; Paul D. Hodgskiss

    1997-01-01

    Fragmentation and reduction in population size are expected to reduce genetic diversity. However, examples from natural populations of forest trees are scarce. The range of Chihuahua spruce retreated northward and fragmented coincident with the warming climate that marked the early Holocene. The isolated populations vary from 15 to 2441 trees, which provided an...

  3. Bioecology of the conifer swift moth, Korscheltellus gracilis, a root feeder associated with spruce-fir decline

    Treesearch

    William E. Wallner; David L. Wagner; Bruce L. Parker; Donald L. Tobi

    1991-01-01

    During the past two decades, the decline of red spruce, Picea rubens Sargent, and balsam fir, Abies balsamea (L), at high elevations (900-1200 m) in eastern North America has evoked concern about the effects of anthropogenic deposition upon terrestrial ecosystems. In many high-elevation forests across New England, as many as 50...

  4. Remote sensing of the distribution and abundance of host species for spruce budworm in Northern Minnesota and Ontario

    Treesearch

    Peter T. Wolter; Philip A. Townsend; Brian R. Sturtevant; Clayton C. Kingdon

    2008-01-01

    Insects and disease affect large areas of forest in the U.S. and Canada. Understanding ecosystem impacts of such disturbances requires knowledge of host species distribution patterns on the landscape. In this study, we mapped the distribution and abundance of host species for the spruce budworm (Choristoneura fumiferana) to facilitate landscape scale...

  5. Juvenility and serial vegetative propagation of Norway spruce clones (Picea abies Karst.).

    Treesearch

    J.B. St. Clair; J. Kleinschmit; J. Svolba

    1985-01-01

    Effects associated with progressive maturation of clones are of greatest concern in clonal tree improvement programs. Serial propagation has been in use at the Lower Saxony Forest Research Institute since 1968 to arrest maturation in Norway spruce clones. By 1980 cuttings were established in the nursery that had been serially propagated from one to five cycles. This...

  6. Penobscot woodlands yield annual cuts

    Treesearch

    A. C. Hart

    1958-01-01

    Two small woodlands, put under management at the Penobscot Experimental Forest in the early 1950's, have yielded continuous annual cuts. The two woodlands, in the spruce-fir type, were selected to be representative of small forest properties in that region.

  7. Tree species composition affects the abundance of rowan (Sorbus aucuparia L.) in urban forests in Finland.

    PubMed

    Hamberg, Leena; Lehvävirta, Susanna; Kotze, D Johan; Heikkinen, Juha

    2015-03-15

    Recent studies have shown a considerable increase in the abundance of rowan (Sorbus aucuparia) saplings in urban forests in Finland, yet the reasons for this increase are not well understood. Here we investigated whether canopy cover or tree species composition, i.e., the basal areas of different tree species in Norway spruce dominated urban forests, affects the abundances of rowan seedlings, saplings and trees. Altogether 24 urban forest patches were investigated. We sampled the number of rowan and other saplings, and calculated the basal areas of trees. We showed that rowan abundance was affected by tree species composition. The basal area of rowan trees (≥ 5 cm in diameter at breast height, dbh) decreased with increasing basal area of Norway spruce, while the cover of rowan seedlings increased with an increase in Norway spruce basal area. However, a decrease in the abundance of birch (Betula pendula) and an increase in the broad-leaved tree group (Acer platanoides, Alnus glutinosa, Alnus incana, Amelanchier spicata, Prunus padus, Quercus robur, Rhamnus frangula and Salix caprea) coincided with a decreasing number of rowans. Furthermore, rowan saplings were scarce in the vicinity of mature rowan trees. Although it seems that tree species composition has an effect on rowan, the relationship between rowan saplings and mature trees is complex, and therefore we conclude that regulating tree species composition is not an easy way to keep rowan thickets under control in urban forests in Finland. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Can Tree Ring Analyses Predict Resilience of Black Spruce Forests to Fire in Interior Alaska?

    NASA Astrophysics Data System (ADS)

    Walker, X. J.; Johnstone, J. F.; Mack, M. C.

    2015-12-01

    Climate change has increased the occurrence, severity, and impact of disturbances on forested ecosystems worldwide. As such there is a growing need to identify factors that contribute to an ecosystem's ability to recover from disturbance, commonly referred to as ecosystem resilience. In trees, drought-induced growth declines may signal decreased ecosystem resilience if mature trees are able to survive in stressful environmental conditions that do not permit successful post-disturbance recruitment and survival. Here we explore links between ecosystem resilience and the growth-climate relationships of pre-fire trees, specifically drought stress signals, across topographic moisture gradients within the boreal forest. We sampled 72 recently (2004) burned black spruce stands within interior Alaska and found the proportion of black spruce relative to deciduous trees decreased post-fire, ranging from almost no change to a 90% decrease. The largest shifts in post-fire species composition occurred in sites where trees showed negative growth responses to warm spring temperatures, and shallow post-fire organic layer depths due to dry site conditions or high fire severity. These sites were generally located at warmer and drier landscape positions, suggesting they are less resilient to disturbance than sites at the wetter end of the gradient. Tree growth-climate responses can provide an estimate of stand environmental stress to ongoing climate change and as such are a valuable tool for predicting landscape variations in forest ecosystem resilience and forecasting future forest composition.

  9. Comparison of riparian and upland forest stand structure and fuel loads in beetle infested watersheds, southern Rocky Mountains

    Treesearch

    Kathleen A. Dwire; Robert Hubbard; Roberto Bazan

    2015-01-01

    Extensive outbreaks of mountain pine beetle (MPB), spruce beetle (SB), and other insects are altering forest stand structure throughout western North America, and thereby contributing to the heterogeneity of fuel distribution. In forested watersheds, conifer-dominated riparian forests frequently occur as narrow linear features in the landscape mosaic and contribute to...

  10. Permafrost conditions at the Upper Kuskokwim river area and its influence on local communities.

    NASA Astrophysics Data System (ADS)

    Kholodov, A. L.; Panda, S. K.; Hanson, T.

    2017-12-01

    Research area located within the zone of discontinuous permafrost distribution. Recent mean annual air temperature here is close to the 0C. It means, that taking in consideration warming influence of the snow cower during winter, mean annual temperature at the ground surface is well above freezing point. It means that presence or absence of permafrost here completely controlled by the ecological conditions. Based on remote sensing data and the surveys conducted in 2016-17 we selected 6 main ecotypes typical for this area: black spruce boreal forest, wetlands, low and tall shrubs, deciduous and mixed forest. Most of them (low shrubs, deciduous and mixed forest) represent different stages of area recovering after forest fires that was confirmed by the presence of ashy layer close to ground surface in soil pits had been dug within these landscapes. Permafrost was observed only within 2 of them: low shrubs and black spruce boreal forest. Within these types of terrain temperature at the bottom of active layer varies from -0.2/-0.5C at the areas of low shrubs, recovered after relatively recent (approximately 30-50 years old) fires to -1/-1.5 within black spruce forest. Active (seasonally thawed) layer as thick as 0.6 to 0.8 m. Warmest ecotypes for the area are tall shrubs and deciduous forest, temperature at the depth close to 1 m is about +3C. At the mixed forest temperature at the same depth consists of +1/+2C. Active (seasonally frozen) layer thickness within permafrost free areas is 1-1.5 m at the drained sites and about 0.5 within wetlands. Ice-rich permafrost underlying the active layer was noticed only within the black spruce forest. Areas which are free of permafrost are much better drained, typical moisture of mineral soil is less than 30% versus 45-50% in seasonally thawed layer. The current state of permafrost and the fact that it presence completely depends on ecosystems limits land use abilities of local inhabitants. Any changes of forest coverage or organic layer thickness will lead to permafrost degradation and initiate thermokarst process or dryness of the area that increases risk of wild fires. Also, shallow soil freezing within wetlands makes shorter the safe period of snow machines operation. Current research should help local communities make more informed decisions in adaptation of resources management and land use.

  11. Barred Owl (Strix varia) nest site characteristics in the boreal forest of Saskatchewan, Canada

    Treesearch

    Kurt M. Mazur; Paul C. James; Shanna D. Frith

    1997-01-01

    Between 1994 and 1996 we located 15 active Barred Owl (Strix varia) nests in the boreal forest of central Saskatchewan, Canada. Eighty-seven percent of Barred Owl nests were located within old mixedwood forest stands. Nest tree species included white spruce (Picea glauca), trembling aspen (Populus tremuloides),...

  12. Climate drivers of bark beetle outbreak dynamics in Norway spruce forests

    Treesearch

    Lorenzo Marini; Bjorn Okland; Anna Maria Jonsson; Barbara Bentz; Allan Carroll; Beat Forster; Jean-Claude Gregoire; Rainer Hurling; Louis Michel Nageleisen; Sigrid Netherer; Hans Peter Ravn; Aaron Weed; Martin Schroeder

    2017-01-01

    Bark beetles are among the most devastating biotic agents affecting forests globally and several species are expected to be favored by climate change. Given the potential interactions of insect outbreaks with other biotic and abiotic disturbances, and the potentially strong impact of changing disturbance regimes on forest resources, investigating climatic drivers of...

  13. Joint proceedings of the 10th Lake States Forest Tree Improvement Conference & 7th Central States Forest Tree Improvement Conference, September 22-24, 1971.

    Treesearch

    USDA FS

    1973-01-01

    Presents 12 papers concerning recent research in forest genetics, physiology, and allied fields. Species discussed include cottonwood, white spruce, jack pine, white pine, aspen, and others. Emphasizes the role of tree improvement in increasing wood-fiber production.

  14. Impact of climate warming-induced increase in drought stress on successional dynamic of a coniferous forest within a dry inner Alpine environment

    NASA Astrophysics Data System (ADS)

    Schuster, R.; Zeisler, B.; Oberhuber, W.

    2012-04-01

    Climate sensitivity of tree growth will effect the development of forest ecosystems under a warmer and drier climate by changing species composition and inducing shifts in forest distribution. We applied dendroclimatological techniques to determine impact of climate warming on radial stem growth of three native and widespread coniferous tree species of the central Austrian Alps (Norway spruce, Picea abies; European larch, Larix decidua; Scots pine, Pinus sylvestris), which grow intermixed at dry-mesic sites within a dry inner Alpine environment (750 m a.s.l., Tyrol, Austria). Time series of annual increments were developed from > 250 saplings and mature trees. Radial growth response to recent climate warming was explored by means of moving response functions (MRF) and evaluation of trends in basal area increment (BAI) for the period 1911 - 2009. Climate-growth relationships revealed significant differences among species in response to water availability. While precipitation in May - June favoured radial growth of spruce and larch, Scots pine growth mainly depended on April - May precipitation. Spruce growth was most sensitive to May - June temperature (inverse relationship). Although MRF coefficients indicated increasing drought sensitivity of all species, which is most likely related to intensified belowground competition for scarce water with increasing stand density and higher evapotranspiration rates due to climate warming, recent BAI trends strikingly differed among species. While BAI of larch was distinctly declining, spruce showed steadily increasing BAI and quite constant BAI was maintained in drought adapted Scots pine, although at lowest level of all species. Furthermore, more favourable growing conditions of spruce in recent decades are indicated by scattered natural regeneration and higher growth rates of younger trees during first decades of their lifespan. Because human interference and wildlife stock is negligible within the study area, results suggest a competitive advantage of shade-tolerant and shallow-rooted late successional spruce over early successional species, whereby the spruce`s competitive strength is most likely related to synergistic effects of shade-tolerance and efficient uptake of small rainfall events by fine roots distributed primarily in upper soil layers. On the other hand, strikingly decreasing trend in BAI of larch is suggested to be due to negative influence of climate warming on tree water status. We conclude that climate warming-induced increase in drought sensitivity changed competitive strength of co-occurring conifers due to differences in inherent adaptive capacity at a drought-prone inner Alpine site.

  15. Identifying calcium sources at an acid deposition-impacted spruce forest: A strontium isotope, alkaline earth element multi-tracer approach

    USGS Publications Warehouse

    Bullen, T.D.; Bailey, S.W.

    2005-01-01

    Depletion of calcium from forest soils has important implications for forest productivity and health. Ca is available to fine feeder roots from a number of soil organic and mineral sources, but identifying the primary source or changes of sources in response to environmental change is problematic. We used strontium isotope and alkaline earth element concentration ratios of trees and soils to discern the record of Ca sources for red spruce at a base-poor, acid deposition-impacted watershed. We measured 87Sr/86Sr and chemical compositions of cross-sectional stemwood cores of red spruce, other spruce tissues and sequential extracts of co-located soil samples. 87Sr/86Sr and Sr/Ba ratios together provide a tracer of alkaline earth element sources that distinguishes the plant-available fraction of the shallow organic soils from those of deeper organic and mineral soils. Ca/Sr ratios proved less diagnostic, due to within-tree processes that fractionate these elements from each other. Over the growth period from 1870 to 1960, 87Sr/86Sr and Sr/Ba ratios of stemwood samples became progressively more variable and on average trended toward values that considered together are characteristic of the uppermost forest floor. In detail the stemwood chemistry revealed an episode of simultaneous enhanced uptake of all alkaline earth elements during the growth period from 1930 to 1960, coincident with reported local and regional increases in atmospheric inputs of inorganic acidity. We attribute the temporal trends in stemwood chemistry to progressive shallowing of the effective depth of alkaline earth element uptake by fine roots over this growth period, due to preferential concentration of fine roots in the upper forest floor coupled with reduced nutrient uptake by roots in the lower organic and upper mineral soils in response to acid-induced aluminum toxicity. Although both increased atmospheric deposition and selective weathering of Ca-rich minerals such as apatite provide possible alternative explanations of aspects of the observed trends, the chemical buffering capacity of the forest floor-biomass pool limits their effectiveness as causal mechanisms. ?? Springer 2005.

  16. Initial observations on using SAR to monitor wildfire scars in boreal forests

    NASA Technical Reports Server (NTRS)

    Kasischke, E. S.; Bourgeau-Chavez, L. L.; French, N. H. F.; Harrell, P.; Christensen, N. L., Jr.

    1992-01-01

    Initial observations on the effects of wildfires in black spruce forests on radar backscatter are presented. Airborne and spaceborne SAR imagery are utilized to illustrate two distinct fire signatures. A theory is presented to explain these differences.

  17. Research update on the brown spruce longhorn beetle, Tetropium fuscum (Fabr.)

    Treesearch

    Jon Sweeney; Peter Silk; Deepa Pureswaran; Leah Flaherty; Junping Wu; Jessica Price; Jerzy M. Gutowski; Peter Mayo

    2009-01-01

    A 3-year research project, funded by the Canadian Forest Service and the Canadian Food Inspection Agency, was initiated in the spring of 2007 to address key issues of provincial and forest industry stakeholders concerning the brown...

  18. Proceedings of the Eighth Lake States Forest Tree Improvement conference, Sept. 12-13, 1967.

    Treesearch

    NCFES

    1968-01-01

    Presents 11 papers concerning recent research in forest genetics, physiology, and allied fields. Species discussed include red pine, jack pine, Scotch pine, black spruce, larch, yellow birch, sugar maple, silver maple, cottonwood, and walnut.

  19. Effects of moisture limitation on tree growth in upland and floodplain forest ecosystems in interior Alaska

    Treesearch

    John. Yarie

    2008-01-01

    The objective of this study was to examine the impact of summer throughfall on the growth of trees, at upland and floodplain locations, in the vicinity of Fairbanks, Alaska. Corrugated clear plastic covers were installed under the canopy of floodplain balsam poplar/white spruce stands and upland hardwood/white spruce stands to control soil moisture recharge as a result...

  20. Genesis of peat-bog soils in the northern taiga spruce forests of the Kola Peninsula

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nikonov, V.V.

    1981-01-01

    The characteristics of soil formation processes in the Peat-Bog soils of waterlogged spruce phytocenoses on the Kola Peninsula are investigated. It is found that the ash composition of the peat layer is determined primarily by the composition of the buried plant residues. The effect of the chemical composition of water feeding the peat bogs is determined. (Refs. 7).

  1. Relationships among foliar chemistry, foliar polyamines, and soil chemistry in red spruce trees growing across the northeastern United States

    Treesearch

    Rakesh Minocha; Walter C. Shortle; Gregory B. Lawrence; Mark B. David; Subhash C. Minocha

    1997-01-01

    Forest trees are constantly exposed to various types of natural and anthropogenic stressors. A major long-term goal of our research is to develop a set of early physiological and biochemical markers of stress in trees before the appearance of visual symptoms. Six red spruce (Picea rubens Sarg.) stands from the northeastern United States were selected...

  2. Effects of permafrost melting on CO2 and CH4 exchange of a poorly drained black spruce lowland

    Treesearch

    Kimberly P. Wickland; Robert G. Striegl; Jason C. Neff; Torsten Sachs

    2006-01-01

    Permafrost melting is occurring in areas of the boreal forest region where large amounts of carbon (C) are stored in organic soils. We measured soil respiration, net CO2 flux, and net CH4 flux during May-September 2003 and March 2004 in a black spruce lowland in interior Alaska to better understand how permafrost thaw in...

  3. Aluminum and calcium in fine root tips of red spruce collected from the forest floor

    Treesearch

    K.T. Smith; W.C. Shortle; W.D. Ostrofsky

    1995-01-01

    Root chemistry is being increasingly used as a marker of biologically relevant soil chemistry. To evaluate this marker, we determined the precision of measurement, the effect of organic soil horizon, and the effect of stand elevation on the chemistry of fine root tips of red spruce (Picea rubens Sarg.) Fine root tips were collected from the F and H...

  4. Effects of aerially applied mexacarbate on western spruce budworm larvae and their parasites in Montana

    Treesearch

    Carroll B. Williams; Patrick J. Shea; Mark D. McGregor

    1979-01-01

    In tests on the Bitterroot National Forest, Montana, in 1965 and 1966, mexacarbate, aerially applied at the rate of 0.15 lb a.i./gal/acre (68.04 g a.iJ3.785 1/0.404 ha), killed about 90 percent of the western spruce budworm (Choristoneura occidentalis Freeman) populations. More parasitized budworm larvae survived treatments than nonparasitized.

  5. Long-distance dispersal of spruce budworm (Choristoneura fumiferana Clemens) in Minnesota (USA) and Ontario (Canada) via the atmospheric pathway

    Treesearch

    Brian R. Sturtevant; Gary L. Achtemeier; Joseph J. Charney; Dean P. Anderson; Barry J. Cooke; Phillip A. Townsend

    2013-01-01

    Dispersal can play an important role in the population dynamics of forest insects, but the role of long-distance immigration and emigration remains unclear due to the difficulty of quantifying dispersal distance and direction. We designed an agent-based spruce budworm flight behavior model that, when interfaced with temperature, wind speed, and precipitation output...

  6. Tolerance of spruce budworm to malathion...Montana, New Mexico populations show no differences

    Treesearch

    Robert L. Lyon; Marion Page; Sylvia J. Brown

    1968-01-01

    In pest control operations by the U.S. Forest Service using malathion sprays, nearly twice as many spruce budworms were killed in Montana as in New Mexico. To find out if budworms in New Mexico had greater tolerance to the insecticide, malathion was applied by topical and aerosol treatments in the laboratory to 6th - instar populations from the two States. No...

  7. Effect of tree-ring detrending method on apparent growth trends of black and white spruce in interior Alaska

    Treesearch

    Patrick F Sullivan; Robert R Pattison; Annalis H Brownlee; Sean M P Cahoon; Teresa N Hollingsworth

    2016-01-01

    Boreal forests are critical sinks in the global carbon cycle. However, recent studies have revealed increasing frequency and extent of wildfires, decreasing landscape greenness, increasing tree mortality and declining growth of black and white spruce in boreal North America. We measured ring widths from a large set of increment cores collected across a vast area of...

  8. Assessing relationships between red spruce radial growth and pollution critical load exceedance values

    Treesearch

    Benjamin J. Engel; Paul G. Schaberg; Gary J. Hawley; Shelly A. Rayback; Jennifer Pontius; Alexandra M. Kosiba; Eric K. Miller

    2016-01-01

    Acidic sulfur (S) and nitrogen (N) deposition depletes cations such as calcium (Ca) from forest soils and has been linked to increases in foliar winter injury that led to the decline of red spruce (Picea rubens Sarg.) in the northeastern United States. We used results from a 30 m resolution steady-state S and N critical load exceedance model for New...

  9. Calcium addition at the Hubbard Brook Experimental Forest increases sugar storage, antioxidant activity and cold tolerance in native red spruce (Picea rubens)

    Treesearch

    Joshua M. Halman; Paul G. Schaberg; Gary J. Hawley; Christopher Eagar

    2008-01-01

    In fall (November 2005) and winter (February 2006), we collected current-year foliage of native red spruce (Picea rubens Sarg.) growing in a reference watershed and in a watershed treated in 1999 with wollastonite (CaSiO3, a slow-release calcium source) to simulate preindustrial soil calcium concentrations (Ca-addition...

  10. Calcium addition at the Hubbard Brook Experimental Forest reduced winter injury to red spruce in a high-injury year

    Treesearch

    Gary J. Hawley; Paul G. Schaberg; Christopher Eagar; Catherine H. Borer

    2006-01-01

    Laboratory experiments have verified that acid-deposition-induced calcium (Ca) leaching reduces the foliar cold tolerance of red spruce (Picea rubens Sarg.) current-year foliage, increasing the risk of winter injury and crown deterioration. However, to date no studies have shown that ambient losses in soil Ca have resulted in increased winter injury...

  11. Contribution of black spruce (Picea mariana) transpiration to growing season evapotranspiration in a subarctic discontinuous permafrost peatland complex

    NASA Astrophysics Data System (ADS)

    Helbig, M.; Warren, R. K.; Pappas, C.; Sonnentag, O.; Berg, A. A.; Chasmer, L.; Baltzer, J. L.; Quinton, W. L.; Patankar, R.

    2016-12-01

    Partitioning the components of evapotranspiration (ET), evaporation and transpiration, has been increasingly important for the better understanding and modeling of carbon, water, and energy dynamics, and for reliable water resources quantification and management. However, disentangling its individual processes remains highly uncertain. Here, we quantify the contribution of black spruce transpiration, the dominant overstory, to ET of a boreal forest-wetland landscape in the southern Taiga Plains. In these ecosystems, thawing permafrost induces rapid landscape change, whereby permafrost-supported forested plateaus are transformed into bogs or fens (wetlands), resulting in tree mortality. Using historical and projected rates of forest-wetland changes, we assess how the contribution of black spruce transpiration to landscape ET might be altered with continued permafrost loss, and quantify the resulting water balance changes. We use two nested eddy covariance flux towers and a footprint model to quantify ET over the entire landscape. Sap flux density of black spruce is measured using the heat ratio method during the 2013 (n=22) and 2014 (n=3) growing seasons, and is used to estimate tree-level transpiration. Allometric relations between tree height, diameter at breast height and sapwood area are derived to upscale tree-level transpiration to overstory transpiration within the eddy covariance footprint. Black spruce transpiration accounts for <10% of total landscape ET. The largest daily contribution of overstory transpiration to landscape ET is observed shortly after the landscape becomes snow-free, continually decreasing throughout the progression of the growing season. Total transpiration is notably lower in 2014 (2.34 mm) than 2013 (2.83 mm) over the same 40-day period, corresponding to 3% of cumulative landscape ET in both years. This difference is likely due to the antecedent moisture conditions, where the 2014 growing season was proceeded by lower than average snowfall. As wetland features contribute a larger percentage to landscape ET than plateaus and expand with thawing permafrost, black spruce transpiration may become a negligible component of the water balance in these environments in the near future, with pronounced implications for the hydrological regime in these ecosystems.

  12. Ozone gradients in a spruce forest stand in relation to wind speed and time of the day

    NASA Astrophysics Data System (ADS)

    Pleijel, H.; Wallin, G.; Karlsson, P. E.; Skärby, L.

    Ozone concentrations were measured outside and inside a 60-year-old 15-20 m tall spruce forest at a wind-exposed forest edge in southwest Sweden, at 3 and 13 m height 15 m outside the forest, and at 3 and 13 m height inside the forest 45 m from the forest edge. Measurements at 3 m were made with three replicate tubes on each site, the replicates being separated by 10 m. In addition, horizontal and vertical wind speeds were measured at 8 m height outside and inside the forest. During daytime, the concentrations inside the forest were generally slightly lower. Negative ozone concentration gradients from the open field into the forest were observed at 3 m height when the wind speed was below approximately 1.5 m s -1. At very low wind speeds, mainly occurring during the night, the ozone concentrations at 3 m height were frequently higher inside the forest than outside the forest. This may be caused by a very large aerodynamic resistance to ozone deposition, due to very small air movements inside the forest under stable conditions. It is concluded that ozone uptake by the trees is likely to be very small at night, even if stomata are not entirely closed. Results from open-top chamber experiments are also discussed.

  13. Microwave dielectric properties of boreal forest trees

    NASA Technical Reports Server (NTRS)

    Xu, G.; Ahern, F.; Brown, J.

    1993-01-01

    The knowledge of vegetation dielectric behavior is important in studying the scattering properties of the vegetation canopy and radar backscatter modelling. Until now, a limited number of studies have been published on the dielectric properties in the boreal forest context. This paper presents the results of the dielectric constant as a function of depth in the trunks of two common boreal forest species: black spruce and trembling aspen, obtained from field measurements. The microwave penetration depth for the two species is estimated at C, L, and P bands and used to derive the equivalent dielectric constant for the trunk as a whole. The backscatter modelling is carried out in the case of black spruce and the results are compared with the JPL AIRSAR data. The sensitivity of the backscatter coefficient to the dielectric constant is also examined.

  14. Low volume undiluted Btk application against heavy gypsy moth population densities in southern Corsica

    Treesearch

    Robert A. Fusco; Jean-Claude Martin

    2003-01-01

    Low volume undiluted applications of Bacillus thuringiensis are common and efficacious against coniferous forest pests such as pine processionary moth and spruce budworm, but have not been common practice against deciduous forest pests due to coverage issues.

  15. BOREAS TGB-8 Photosynthetic Rate Data over the SSA-OBS and the SSA-OJP

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Lerdau, Manuel

    2000-01-01

    The BOREAS TGB-8 team collected data to investigate the controls over NMHC fluxes from boreal forest tree species. This data set includes measurements of photosynthetic rates at mature jack pine and black spruce sites. The data were collected at the OJP and OBS tower flux locations in the BOREAS SSA. These areas contained mature stands of jack pine and black spruce and were the focal sites in the BOREAS program for studies of biosphere/atmosphere exchange from these two habitat types. The OBS site is situated in a black spruce/sphagnum bog with the largest trees 155 years old and 10-15 m tall. The OJP site is in a jack pine forest, 80 to 120 years old, which lies on a sandy bench of glacial outwash with the largest tree standing 15 m tall. Temporally, the data cover the period of 24-May-1994 to 19-Sep-1994. The data are stored in tabular ASCII files.

  16. BOREAS TGB-8 Starch Concentration Data Over the SSA-OBS and the SSA-OJP

    NASA Technical Reports Server (NTRS)

    Lerdau, Manuel; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOREAS TGB-8 team collected data to investigate the controls over NMHC fluxes from boreal forest tree species. This data set includes measurements of starch concentrations in foliar samples at mature jack pine and black spruce sites. The data were collected at the OJP and OBS tower flux locations in the BOREAS SSA. These areas contained mature stands of jack pine and black spruce and were the focal sites in the BOREAS program for studies of biosphere/atmosphere exchange from these two habitat types. The OBS site is situated in a black spruce/sphagnum bog with the largest trees 155 years old and 10-15 m tall. The OJP site is in a jack pine forest, 80 to 120 years old, which lies on a sandy bench of glacial outwash with the largest tree standing 15 m tall. Temporally, the data cover the period of 24-May-1994 to 19-Sep-1994. The data are stored in tabular ASCII files.

  17. Simulation of the effect of air pollution on forest ecosystems in a region

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tarko, A.M.; Bykadorov, A.V.; Kryuchkov, V.V.

    1995-03-01

    This article describes a model of air pollution effects on spruce in forests of the northern taiga regions which have been exposed to air pollution from a large metallurgical industrial complex. Both the predictions the model makes about forest ecosystem degradation zones and the limitations of the model are discussed. 5 refs., 1 fig.

  18. Pennsylvania boreal conifer forests and their bird communities: past, present, and potential

    Treesearch

    Douglas A. Gross

    2010-01-01

    Pennsylvania spruce (Picea spp.)- and eastern hemlock (Tsuga canadensis)-dominated forests, found primarily on glaciated parts of the Allegheny Plateau, are relicts of boreal forest that covered the region following glacial retreat. The timber era of the late 1800s and early 1900s (as late as 1942) destroyed most of the boreal...

  19. Stand hazard rating for central Idaho forests

    Treesearch

    Robert Steele; Ralph E. Williams; Julie C. Weatherby; Elizabeth D. Reinhardt; James T. Hoffman; R. W. Thier

    1996-01-01

    Growing concern over sustainability of central ldaho forests has created a need to assess the health of forest stands on a relative basis. A stand hazard rating was developed as a composite of 11 individual ratings to compare the health hazards of different stands. The composite rating includes Douglas-fir beetle, mountain pine beetle, western pine beetle, spruce...

  20. Morphological and functional diversity of ectomycorrhizal fungi on Roan Mountain (NC/TN)

    Treesearch

    Claire Bird; Coleman McCleneghan

    2005-01-01

    A comparison of ectomycorrhizal morphotypes and hypogeous fungi (truffles and false-truffles) in northern hardwood and spruce-fir forests on Roan Mountain (NC/TN) was performed to increase our knowledge of the fungal communities in the Southern Appalachian high elevation forests. These forests are home to an endangered subspecies and mycophagist, the Carolina northern...

  1. Relationships between Sitka black-tailed deer and their habitat.

    Treesearch

    Thomas A. Hanley

    1984-01-01

    Old-growth, western hemlock-Sitka spruce forest in southeastern Alaska is an important element of the habitat of Sitka black-tailed deer. The conversion of uneven-aged, old-growth forests to even-aged, second-growth forests has generated concern about the future carrying capacity of the habitat for deer, especially where snow accumulation is common on winter ranges....

  2. Modeling insect disturbance across forested landscapes: Insights from the spruce budworm

    Treesearch

    Brian R. Sturtevant; Barry J. Cooke; Daniel D. Kneeshaw; David A. MacLean

    2015-01-01

    Insects are important disturbance agents affecting temperate and boreal biomes (Wermelinger 2004; Johnson et al. 2005; Cooke et al. 2007; Raffa et al. 2008). Defoliating insects in particular have historically affected a staggering area of North American forests, particularly across the boreal biome (Fig. 5.1). Principal among these boreal forest defoliators is the...

  3. Elemental cycling response of an Adirondack subalpine spruce-fir forest to atmospheric and environmental change

    Treesearch

    Andrew J. Friedland; Eric K. Miller

    1996-01-01

    Patterns and trends in forest elemental cycling can become more apparent in the presence of atmospheric perturbations. High-elevation forests of the northeastern United States have received large amounts of atmospheric deposition of pollutants, which have altered natural elemental cycling and retention rates in a variety of ways. This study examined atmospheric...

  4. Simulated effects of reduced sulfur, nitrogen, and base cation deposition on soils and solutions in Southern Appalachian forests

    Treesearch

    D.W. Johnson; R.B. Susfalk; P.F. Brewer; W.T. Swank

    1999-01-01

    Effects of reduced deposition of N, S, and CB on nutrient pools, fluxes, soil, and soil solution chemistry were simulated for two Appalachian forest ecosystems using the nutrient cycling model. In the extremely acidic, N- and S-saturated red spruce (Picea rubens (Sarg.)) forest (Nolan Divide), reducing

  5. Managing forest disturbances and community responses: lessons from the Kenai Peninsula, Alaska.

    Treesearch

    Courtney G. Flint; Richard Haynes

    2006-01-01

    Managing forest disturbances can be complicated by diverse human community responses. Interview and quantitative analysis of mail surveys were used to assess risk perceptions and community actions in response to forest disturbance by spruce bark beetles. Despite high risk perception of immediate threats to personal safety and property, risk perceptions of broader...

  6. Seeing the bigger picture: multi-partner spruce restoration in the central and southern Appalachian mountains

    Treesearch

    Jack Tribble; Thomas Minney; Catherine Johnson; Ken. Sturm

    2010-01-01

    Habitat-based ecosystem partnerships are necessary for implementing strategic forest restoration plans. Overwhelming environmental threats such as climate change and invasive pests and pathogens could have traumatic and devastating effects to our native forests. Additionally, past land-use history has left existing forests isolated, fragmented and in some cases...

  7. Diapause and overwintering of two spruce bark beetle species

    PubMed Central

    Hansen, E. Matthew; Schopf, Axel; Ragland, Gregory J.; Stauffer, Christian; Bentz, Barbara J.

    2017-01-01

    Abstract Diapause, a strategy to endure unfavourable conditions (e.g. cold winters) is commonly found in ectothermic organisms and is characterized by an arrest of development and reproduction, a reduction of metabolic rate, and an increased resistance to adversity. Diapause, in addition to adaptations for surviving low winter temperatures, significantly influences phenology, voltinism and ultimately population growth. We review the literature on diapause and overwintering behaviour of two bark beetle species that affect spruce‐dominated forests in the northern hemisphere, and describe and compare how these strategies can influence population dynamics. The European spruce bark beetle Ips typographus (L.) (Coleoptera, Curculionidae) is the most important forest pest of Norway spruce in Europe. It enters an adult reproductive diapause that might be either facultative or obligate. Obligate diapausing beetles are considered strictly univoltine, entering this dormancy type regardless of environmental cues. Facultative diapausing individuals enter diapause induced by photoperiod, modified by temperature, thus being potentially multivoltine. The spruce beetle Dendroctonus rufipennis (Kirby) (Coleoptera: Curculionidae) infests all spruce species in its natural range in North America. A facultative prepupal diapause is averted by relatively warm temperatures, resulting in a univoltine life cycle, whereas cool temperatures induce prepupal diapause leading to a semivoltine cycle. An adult obligate diapause in D. rufipennis could limit bi‐ or multivoltinism. We discuss and compare the influence of diapause and overwinter survival on voltinism and population dynamics of these two species in a changing climate and provide an outlook on future research. PMID:28979060

  8. Decomposition of soil organic matter from boreal black spruce forest: Environmental and chemical controls

    USGS Publications Warehouse

    Wickland, K.P.; Neff, J.C.

    2008-01-01

    Black spruce forests are a dominant covertype in the boreal forest region, and they inhabit landscapes that span a wide range of hydrologic and thermal conditions. These forests often have large stores of soil organic carbon. Recent increases in temperature at northern latitudes may be stimulating decomposition rates of this soil carbon. It is unclear, however, how changes in environmental conditions influence decomposition in these systems, and if substrate controls of decomposition vary with hydrologic and thermal regime. We addressed these issues by investigating the effects of temperature, moisture, and organic matter chemical characteristics on decomposition of fibric soil horizons from three black spruce forest sites. The sites varied in drainage and permafrost, and included a "Well Drained" site where permafrost was absent, and "Moderately well Drained" and "Poorly Drained" sites where permafrost was present at about 0.5 m depth. Samples collected from each site were incubated at five different moisture contents (2, 25, 50, 75, and 100% saturation) and two different temperatures (10??C and 20??C) in a full factorial design for two months. Organic matter chemistry was analyzed using pyrolysis gas chromatography-mass spectrometry prior to incubation, and after incubation on soils held at 20??C, 50% saturation. Mean cumulative mineralization, normalized to initial carbon content, ranged from 0.2% to 4.7%, and was dependent on temperature, moisture, and site. The effect of temperature on mineralization was significantly influenced by moisture content, as mineralization was greatest at 20??C and 50-75% saturation. While the relative effects of temperature and moisture were similar for all soils, mineralization rates were significantly greater for samples from the "Well Drained" site compared to the other sites. Variations in the relative abundances of polysaccharide-derivatives and compounds of undetermined source (such as toluene, phenol, 4-methyl phenol, and several unidentifiable compounds) could account for approximately 44% of the variation in mineralization across all sites under ideal temperature and moisture conditions. Based on our results, changes in temperature and moisture likely have similar, additive effects on in situ soil organic matter (SOM) decomposition across a wide range of black spruce forest systems, while variations in SOM chemistry can lead to significant differences in decomposition rates within and among forest sites. ?? 2007 Springer Science+Business Media B.V.

  9. Will changes in root-zone temperature in boreal spring affect recovery of photosynthesis in Picea mariana and Populus tremuloides in a future climate?

    PubMed

    Fréchette, Emmanuelle; Ensminger, Ingo; Bergeron, Yves; Gessler, Arthur; Berninger, Frank

    2011-11-01

    Future climate will alter the soil cover of mosses and snow depths in the boreal forests of eastern Canada. In field manipulation experiments, we assessed the effects of varying moss and snow depths on the physiology of black spruce (Picea -mariana (Mill.) B.S.P.) and trembling aspen (Populus tremuloides Michx.) in the boreal black spruce forest of western Québec. For 1 year, naturally regenerated 10-year-old spruce and aspen were grown with one of the following treatments: additional N fertilization, addition of sphagnum moss cover, removal of mosses, delayed soil thawing through snow and hay addition, or accelerated soil thawing through springtime snow removal. Treatments that involved the addition of insulating moss or snow in the spring caused lower soil temperature, while removing moss and snow in the spring caused elevated soil temperature and thus had a warming effect. Soil warming treatments were associated with greater temperature variability. Additional soil cover, whether moss or snow, increased the rate of photosynthetic recovery in the spring. Moss and snow removal, on the other hand, had the opposite effect and lowered photosynthetic activity, especially in spruce. Maximal electron transport rate (ETR(max)) was, for spruce, 39.5% lower after moss removal than with moss addition, and 16.3% lower with accelerated thawing than with delayed thawing. Impaired photosynthetic recovery in the absence of insulating moss or snow covers was associated with lower foliar N concentrations. Both species were affected in that way, but trembling aspen generally reacted less strongly to all treatments. Our results indicate that a clear negative response of black spruce to changes in root-zone temperature should be anticipated in a future climate. Reduced moss cover and snow depth could adversely affect the photosynthetic capacities of black spruce, while having only minor effects on trembling aspen.

  10. Expansion of forest stands into tundra in the Noatak National Preserve, northwest Alaska

    USGS Publications Warehouse

    Suarez, F.; Binkley, Dan; Kaye, Margot W.; Stottlemyer, R.

    1999-01-01

    Temperatures across the northern regions of North America have been increasing for 150 years, and forests have responded to this increase. In the Noatak National Preserve in Alaska, white spruce (Picea glauca [Moench] Voss) forests reach their northern limit, occurring primarily on well-drained sites and as gallery forests along streams. Rolling plateaus of tundra separate the white spruce forests into disjunct stands. We examined patterns of tree age, tree growth, and tree encroachment into tundra ecosystems in six stands along the Agashashok River. Warming over the past 150 years appears to have increased tree growth and resulted in forest expansion into adjacent tundra ecosystems. The forest/tundra ecotone shifted by about 80 to 100 m into the tundra in the past 200 years, as evidenced by declining maximum tree age with distance towards the tundra. The decadal-scale pattern of tree establishment at the farthest extent of trees into the tundra (the tundra-forest ecotone) correlated with the detrended growth index for trees within the forests; climate conditions that led to higher tree growth appeared to foster tree establishment in the tundra. This recent forest expansion has occurred across topographic boundaries, from well-drained soils on slopes onto poorly drained, flatter areas of tundra. Further expansion of the forests may be limited by more severe wind exposure and poor drainage that make the majority of tundra less suitable for trees.

  11. Updating beliefs and combining evidence in adaptive forest management under climate change: a case study of Norway spruce (Picea abies L. Karst) in the Black Forest, Germany.

    PubMed

    Yousefpour, Rasoul; Temperli, Christian; Bugmann, Harald; Elkin, Che; Hanewinkel, Marc; Meilby, Henrik; Jacobsen, Jette Bredahl; Thorsen, Bo Jellesmark

    2013-06-15

    We study climate uncertainty and how managers' beliefs about climate change develop and influence their decisions. We develop an approach for updating knowledge and beliefs based on the observation of forest and climate variables and illustrate its application for the adaptive management of an even-aged Norway spruce (Picea abies L. Karst) forest in the Black Forest, Germany. We simulated forest development under a range of climate change scenarios and forest management alternatives. Our analysis used Bayesian updating and Dempster's rule of combination to simulate how observations of climate and forest variables may influence a decision maker's beliefs about climate development and thereby management decisions. While forest managers may be inclined to rely on observed forest variables to infer climate change and impacts, we found that observation of climate state, e.g. temperature or precipitation is superior for updating beliefs and supporting decision-making. However, with little conflict among information sources, the strongest evidence would be offered by a combination of at least two informative variables, e.g., temperature and precipitation. The success of adaptive forest management depends on when managers switch to forward-looking management schemes. Thus, robust climate adaptation policies may depend crucially on a better understanding of what factors influence managers' belief in climate change. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Discerning environmental factors affecting current tree growth in Central Europe.

    PubMed

    Cienciala, Emil; Russ, Radek; Šantrůčková, Hana; Altman, Jan; Kopáček, Jiří; Hůnová, Iva; Štěpánek, Petr; Oulehle, Filip; Tumajer, Jan; Ståhl, Göran

    2016-12-15

    We examined the effect of individual environmental factors on the current spruce tree growth assessed from a repeated country-level statistical landscape (incl. forest) survey in the Czech Republic. An extensive set of variables related to tree size, competition, site characteristics including soil texture, chemistry, N deposition and climate was tested within a random-effect model to explain growth in the conditions of dominantly managed forest ecosystems. The current spruce basal area increment was assessed from two consecutive landscape surveys conducted in 2008/2009 and six years later in 2014/2015. Tree size, age and competition within forest stands were found to be the dominant explanatory variables, whereas the expression of site characteristics, environmental and climatic drives was weaker. The significant site variables affecting growth included soil C/N ratio and soil exchangeable acidity (pH KCl; positive response) reflecting soil chemistry, long-term N-deposition (averaged since 1975) in combination with soil texture (clay content) and Standardized Precipitation Index (SPI), a drought index expressing moisture conditions. Sensitivity of growth to N-deposition was positive, although weak. SPI was positively related to and significant in explaining tree growth when expressed for the growth season. Except SPI, no significant relation of growth was determined to altitude-related variables (temperature, growth season length). We identified the current spruce growth optimum at elevations about 800ma.s.l. or higher in the conditions of the country. This suggests that at lower elevations, limitation by a more pronounced water deficit dominates, whereas direct temperature limitation may concern the less frequent higher elevations. The mixed linear model of spruce tree growth explained 55 and 65% of the variability with fixed and random effects included, respectively, and provided new insights on the current spruce tree growth and factors affecting it within the environmental gradients of the country. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Can a fake fir tell the truth about Swiss needle cast?

    EPA Science Inventory

    A key question in dendrochronology to reconstruct forest disturbance history is how to distinguish between the effects of Swiss needle cast (SNC) and other forest disturbance agents (e.g., Douglas-fir beetle, tussock moth, western spruce budworm, laminated root rot, Armillaria ro...

  14. (abstract) Monitoring Seasonal Change in Taiga Forests Using ERS-1 SAR Data

    NASA Technical Reports Server (NTRS)

    Way, JoBea; Rignot, Eric; McDonald, Kyle; Viereck, Leslie; Williams, Cynthia; Adams, Phyllis; Payne, Cheryl; Wood, William

    1993-01-01

    Sensitivity of radar backscatter to the dielectric and geometric character of forested regions suggests significant changes in backscatter are expected with season due to freezing temperatures, snow, wind, leaf fall, and drought. The first European Remote Sensing Satellite, ERS-1, offers a unique opportunity to monitor a complete seasonal cycle for the Alaskan taiga forest ecosystem with synthetic aperture radar. During the 3-day repeat Commissioning Phase of ERS-1, from August 1991to December 1991, ERS-1 SAR data were collected in the region of Manley Hot Springs, Alaska, along the Tanana River, west of Fairbanks. In parallel with the SAR data collection, meteorological data from three weather stations positioned in three forest stands were collected continuously along with in situ measurements of the dielectric and moisture properties of the canopy and of ground cover which were collected during each overflight. The in situ data were collected in floodplain forest stands dominated by balsam poplar, white spruce, and black spruce. These results from the Commissioning Phase as well as preliminary results from the 35-day Repeat Phase will be presented.

  15. A new mechanism for calcium loss in forest-floor soils

    USGS Publications Warehouse

    Lawrence, G.B.; David, M.B.; Shortle, W.C.

    1995-01-01

    CALCIUM is the fifth most abundant element in trees, and is an essential component for wood formation and the maintenance of cell walls. Depletion of Ca from the rooting zone can result in acidification of soil1 and surface water2 and possibly growth decline and dieback of red spruce3,4. During the past six decades, concentrations of root-available Ca (exchangeable and acid-ex tract able forms) in forest-floor soils have decreased in the northeastern United States5,6. Both net forest growth and acid deposition have been put forth as mechanisms that can account for this Ca depletion5,6. Here, however, we present data collected in red spruce forests in the northeastern United States that are inconsistent with either of these mechanisms. We propose that aluminium, mobilized in the mineral soil by acid deposition, is transported into the forest floor in a reactive form that reduces storage of Ca, and thus its availability for root uptake. This results in potential stress to trees and, by increasing the demand for Ca, also decreases neutralization of drainage waters, thereby leading to acidification of lakes and streams.

  16. Properties of dissolved and total organic matter in throughfall, stemflow and forest floor leachate of Central European forests

    NASA Astrophysics Data System (ADS)

    Bischoff, S.; Schwarz, M. T.; Siemens, J.; Thieme, L.; Wilcke, W.; Michalzik, B.

    2014-10-01

    For the first time, we investigated the composition of dissolved organic matter (DOM) compared to total OM (TOM, consisting of DOM and particulate OM, POM) in throughfall, stemflow and forest floor leachate of beech and spruce forests using solid state 13C nuclear magnetic resonance spectroscopy. We hypothesized that the composition and properties of OM in forest ecosystem water samples differed between DOM and TOM and between the two tree species. Under beech, a contribution of phyllosphere-derived fresh POM was echoed in structural differences. Compared with DOM, TOM exhibited higher relative intensities for the alkyl C region, representing aliphatic C from less decomposed organic material, and lower relative intensities for lignin-derived and aromatic C of the aryl C region, resulting in lower aromaticity indices and reduced humification intensities. Since differences in the structural composition of DOM and TOM were less pronounced under spruce than under beech, we suspect a~tree species-related effect on the origin of OM composition and resulting properties (e.g. recalcitrance, allelopathic potential).

  17. Effects of air pollution and climatic factors on Norway spruce forests in the Orlicke hory Mts. (Czech Republic), 1979-2014

    Treesearch

    Stanislav Vacek; Iva Hunova; Zdenek Vacek; Pavla Hejcmanova; Vilem Podrazsky; Jan Kral; Tereza Putalova; W. Keith Moser

    2015-01-01

    The area of the Orlicke hory Mts. has been characterised by decline and disturbances of Norway spruce (Picea abies/L./Karst.) stands since the 1980s. Currently, only three permanent research plots have been preserved from the original sixteen established plots in this region. In the present study, the health status, as indicated by defoliation, mortality, and...

  18. Studies in the wilderness areas of the Kenai National Wildlife Refuge: fire, bark beetles, human development, and climate change

    Treesearch

    Edward E. Berg

    2000-01-01

    Wilderness areas comprise 65% of the 1.92 million acre Kenai National Wildlife Refuge, Alaska. Fire history studies indicate that fire frequency increased substantially in both white and black spruce forests after European settlement. Dendrochronolgy studies indicate that regional-scale spruce bark beetle outbreaks occurred in the 1820s, 1880s, and 1970s. None of these...

  19. Characteristics of organic soil in black spruce forests: implications for the application of land surface and ecosystem models in cold regions

    Treesearch

    Shuhua Yi; Kristen Manies; Jennifer Harden; David McGuire

    2009-01-01

    Soil organic layers (OL) play an important role in land-atmosphere exchanges of water, energy and carbon in cold environments. The proper implementation of OL in land surface and ecosystem models is important for predicting dynamic responses to climate warming. Based on the analysis of OL samples of black spruce (Picea mariana), we recommend that...

  20. Heart Rots of Engelmann Spruce and Subalpine Fir in the Central Rocky Mountain Region (FIDL)

    Treesearch

    T.E. Hinds

    1977-01-01

    Engelmann spruce (Picea engelmannii)-subalpine fir (Abies lasiocarpa) forests are widely distributed in western North America--from the northern Rocky Mountains of British Columbia and Alberta southward into Arizona and New Mexico. They occur at elevations of 2,000 to 7,000 feet in their northern range whereas they are found from about 8,000 to 12,000 feet in the south...

  1. Balsam fir conservation and red spruce ecosystem restoration initiatives in the West Virginia highlands

    Treesearch

    Corey A. Bonasso; David W. Saville

    2010-01-01

    The West Virginia Highlands Conservancy has been working for more than a decade to protect, conserve, and restore the spruce-fir forests in West Virginia. Beginning in the mid 1990s an effort was initiated to conserve balsam fir in West Virginia where it reaches its southern most extent in North America. This work led to further efforts which have focused on the...

  2. Historical patterns of spruce budworm defoliation and bark beetle outbreaks in North American conifer forests: an atlas and description of digital maps

    Treesearch

    David W. Williams; Richard A. Birdsey

    2003-01-01

    This atlas presents maps of historical defoliation by the eastern and western spruce budworms and historical outbreaks of the mountain and southern pine beetles during the past half century. The maps encompass various regions of the conterminous United States and eastern Canada. This publication also serves as documentation for an extended set of digital maps, which...

  3. Growth comparison of northern white-cedar to balsam fir and red spruce by site class

    Treesearch

    Philip V. Hofmeyer; Laura S. Kenefic; Robert S. Seymour; John C. Brissette

    2006-01-01

    Though northern white-cedar is a common and economically important component of the Acadian Forest of Maine and adjacent Canada, there is little regional data about the growth and development of this species. Sixty sites in northern Maine were used to compare growth of cedar to that of red spruce and balsam fir along a range of site classes and light exposures. On...

  4. Concentrations of Ca and Mg in early stages of sapwood decay in red spruce, eastern hemlock, red maple, and paper birch

    Treesearch

    Kevin T. Smith; Walter C. Shortle; Jody Jellison; Jon Connolly; Jonathan Schilling

    2007-01-01

    The decay of coarse woody debris is a key component in the formation of forest soil and in the biogeochemical cycles of Ca and Mg. We tracked changes in density and concentration of Ca and Mg in sapwood of red maple (Acer rubrum L.), red spruce (Picea rubens Sarg.), paper birch (Betula papyrifera Marsh.), and...

  5. Management implications of using tree shelters for restoration of high elevation spruce-fir forests in the Rocky Mountains

    Treesearch

    Douglass F. Jacobs

    2012-01-01

    This paper presents a summary of a research project designed to study the use of tree shelters as a means to provide initial shade for planted Engelmann spruce (Picea englemannii Parry ex Engelm.) seedlings on a reforestation site in southwestern Colorado where several past planting attempts had failed. Study results following 2, 6, and 11 growing seasons were formally...

  6. Historical patterns of western spruce budworm and Douglas-fir tussock moth outbreaks in the northern Blue Mountains, Oregon, since A.D. 1700.

    Treesearch

    Thomas Swetnam; Boyd E. Wickman; H. Gene Paul; Christopher H. Baisan

    1995-01-01

    Dendroecology methods were used to reconstruct a three-century history of western spruce budworm and Douglas-fir tussock moth outbreaks in the Blue Mountains of northeastern Oregon. Comparisons of 20th century Forest Service documentary records and host and nonhost tree-ring width chronologies provided an objective basis for distinguishing climatic effects from insect-...

  7. Spruce bark beetle in Sumava NP: A precedent case of EU Wilderness Protection, the role of NGOs and the public in wilderness protection

    Treesearch

    Jaromir Blaha; Vojtech Kotecky

    2015-01-01

    Sumava National Park, in the Czech Republic, is, along with the adjacent Bayerischer Wald NP in Germany, one of the largest wilderness areas in Western and Central Europe. Mountain spruce forests here have been heavily influenced by natural disturbances. Following years of debate about conservation management in the national park, logging operations on the Czech side...

  8. Contrasting drivers and trends of coniferous and deciduous tree growth in interior Alaska.

    PubMed

    Cahoon, Sean M P; Sullivan, Patrick F; Brownlee, Annalis H; Pattison, Robert R; Andersen, Hans-Erik; Legner, Kate; Hollingsworth, Teresa N

    2018-03-22

    The boreal biome represents approximately one third of the world's forested area and plays an important role in global biogeochemical and energy cycles. Numerous studies in boreal Alaska have concluded that growth of black and white spruce is declining as a result of temperature-induced drought stress. The combined evidence of declining spruce growth and changes in the fire regime that favor establishment of deciduous tree species has led some investigators to suggest the region may be transitioning from dominance by spruce to dominance by deciduous forests and/or grasslands. Although spruce growth trends have been extensively investigated, few studies have evaluated long-term radial growth trends of the dominant deciduous species (Alaska paper birch and trembling aspen) and their sensitivity to moisture availability. We used a large and spatially extensive sample of tree cores from interior Alaska to compare long-term growth trends among contrasting tree species (white and black spruce vs. birch and aspen). All species showed a growth peak in the mid-1940s, although growth following the peak varied strongly across species. Following an initial decline from the peak, growth of white spruce showed little evidence of a trend, while black spruce and birch growth showed slight growth declines from ~1970 to present. Aspen growth was much more variable than the other species and showed a steep decline from ~1970 to present. Growth of birch, black and white spruce was sensitive to moisture availability throughout most of the tree-ring chronologies, as evidenced by negative correlations with air temperature and positive correlations with precipitation. However, a positive correlation between previous July precipitation and aspen growth disappeared in recent decades, corresponding with a rise in the population of the aspen leaf miner (Phyllocnistis populiella), an herbivorous moth, which may have driven growth to a level not seen since the early 20th century. Our results provide important historical context for recent growth and raise questions regarding competitive interactions among the dominant tree species and exchanges of carbon and energy in the warming climate of interior Alaska. © 2018 by the Ecological Society of America.

  9. Changes in canopy processes following whole-forest canopy nitrogen fertilization of a mature spruce-hemlock forest

    Treesearch

    E. Gaige; D.B. Dail; D.Y. Hollinger; E.A. Davidson; I.J. Fernandez; H. Sievering; A. White; W. Halteman

    2007-01-01

    Most experimental additions of nitrogen to forest ecosystems apply the N to the forest floor, bypassing important processes taking place in the canopy, including canopy retention of N and/or conversion of N from one form to another. To quantify these processes, we carried out a large-scale experiment and determined the fate of nitrogen applied directly to a mature...

  10. Northeastern conifer research: Multiple species and multiple values

    Treesearch

    Laura S. Kenefic; John C. Brissette; Richard W. Judd

    2014-01-01

    The northern conifer, or spruce-fir, forest of the northeastern USA and adjacent Canada has had a defining influence on the economy and culture of the region. The same can be said of the USDA Forest Service’s research in this forest, which began more than 100 years ago. Forest Service research has evolved since that time in response to changes in the needs and...

  11. Bat habitat use in White Mountain National Forest

    Treesearch

    Rachel A. Krusic; Mariko Yamasaki; Christopher D. Neefus; Peter J. Pekins

    1996-01-01

    In 1992 and 1993, we surveyed the foraging and feeding activity of bat species with broadband bat detectors at 2 foliage heights in 4 age classes of northern hardwood and spruce/fir forest stands in White Mountain National Forest, New Hampshire and Maine. The association of bat activity with trails and water bodies and the effect of elevation were measured. Mist nets,...

  12. Assessment of forest quality in southwestern Poland with the use of remotely sensed data

    Treesearch

    Zbigniew Bochenek; Andrzej Ciolkosz; Maria Iracka

    1998-01-01

    A three-stage approach was applied to assess the quality of forests in southwestern Poland, which are heavily affected with air pollution and insect infestations. In the first stage a ground evaluation of spruce stands was done within the selected test areas. Three main characteristics of forest quality were determined as a result of these works: defoliation,...

  13. Climate warming shifts carbon allocation from stemwood to roots in calcium-depleted spruce forests

    Treesearch

    Andrei G. ​Lapenis; Gregory B. Lawrence; Alexander Heim; Chengyang Zheng; Walter Shortle

    2013-01-01

    Increased greening of northern forests, measured by the Normalized Difference Vegetation Index (NDVI), has been presented as evidence that a warmer climate has increased both net primary productivity (NPP) and the carbon sink in boreal forests. However, higher production and greener canopies may accompany changes in carbon allocation that favor foliage or fine roots...

  14. Modelling and economic evaluation of forest biome shifts under climate change in Southwest Germany

    Treesearch

    Marc Hanewinkel; Susan Hummel; Dominik Cullmann

    2010-01-01

    We evaluated the economic effects of a predicted shift from Norway spruce (Picea abies) to European beech (Fagus sylvatica) for a forest area of 1.3 million ha in southwest Germany. The shift was modelled with a generalized linear model (GLM) by using presence/absence data from the National Forest Inventory in Baden-Wurttemberg...

  15. Potential of decaying wood to restore root-available base cations in depleted forest soils

    Treesearch

    Walter C. Shortle; Kevin T. Smith; Jody Jellison; Jonathan S. Schilling

    2012-01-01

    The depletion of root-available Ca in northern forest soils exposed to decades of increased acid deposition adversely affects forest health and productivity. Laboratory studies indicated the potential of wood-decay fungi to restore lost Ca. This study presents changes in concentration of Ca, Mg, and K in sapwood of red spruce (Picea rubens Sarg.),...

  16. Diet and food availability of the Virginia northern flying squirrel (Glaucomys sabrinus fuscus): implications for dispersal in a fragmented forest

    Treesearch

    Stephanie E. Trapp; Winston P. Smith; Elizabeth A. Flaherty

    2017-01-01

    A history of timber harvest in West Virginia has reduced red spruce (Picea rubens) forests to < 10% of their historic range and resulted in considerable habitat fragmentation for wildlife species associated with these forests. The Virginia northern flying squirrel (Glaucomys sabrinus fuscus) has been described as a red...

  17. The lost research of early northeastern spruce-fir experimental forests: a tale of lost opportunities

    Treesearch

    Kate Berven; Laura Kenefic; Aaron Weiskittel; Mark Twery; Jeremy. Wilson

    2013-01-01

    Long-term research is critical to our understanding of forest dynamics. Observations made over decades or centuries provide valuable insight into the effects of natural and anthropogenic disturbances, and allow scientists and forest managers to determine which management regimes succeed and which ones fail in terms of desired objectives. Unfortunately, many long-term...

  18. Tree variables related to growth response and acclimation of advance regeneration of Norway spruce and other coniferous species after release

    Treesearch

    Marek Metslaid; Kalev Jogiste; Eero Nikinma; W. Keith Moser; Albert Porcar-Castell

    2007-01-01

    Modern forestry has been evolving towards multiple-use of forests and maintenance of biodiversity. Interest in integrating natural forest dynamics into management planning and silvicultural practices has increased as a result of concerns related to biodiversity values and maintaining ecological functions in managed forests. Taking advantage of naturally formed...

  19. Recent acceleration of biomass burning and carbon losses in Alaskan forests and peatlands

    USGS Publications Warehouse

    Turetsky, M.R.; Kane, E.S.; Harden, J.W.; Ottmar, R.D.; Manies, K.L.; Hoy, E.; Kasischke, E.S.

    2011-01-01

    Climate change has increased the area affected by forest fires each year in boreal North America. Increases in burned area and fire frequency are expected to stimulate boreal carbon losses. However, the impact of wildfires on carbon emissions is also affected by the severity of burning. How climate change influences the severity of biomass burning has proved difficult to assess. Here, we examined the depth of ground-layer combustion in 178 sites dominated by black spruce in Alaska, using data collected from 31 fire events between 1983 and 2005. We show that the depth of burning increased as the fire season progressed when the annual area burned was small. However, deep burning occurred throughout the fire season when the annual area burned was large. Depth of burning increased late in the fire season in upland forests, but not in peatland and permafrost sites. Simulations of wildfire-induced carbon losses from Alaskan black spruce stands over the past 60 years suggest that ground-layer combustion has accelerated regional carbon losses over the past decade, owing to increases in burn area and late-season burning. As a result, soils in these black spruce stands have become a net source of carbon to the atmosphere, with carbon emissions far exceeding decadal uptake.

  20. Spatial and temporal variability in forest-atmosphere CO2 exchange

    Treesearch

    D.Y. Hollinger; J. Aber; B. Dail; E.A. Davidson; S.M. Goltz; et al.

    2004-01-01

    Seven years of carbon dioxide flux measurements indicate that a ∼ 90-year-old spruce dominated forest in Maine, USA, has been sequestering 174±46 gCm-2 yr-1 (mean±1 standard deviation, nocturnal friction velocity (u*) threshold >0.25ms-1...

  1. Spatial variation in population dynamics of Sitka mice in floodplain forests.

    Treesearch

    T.A. Hanley; J.C. Barnard

    1999-01-01

    Population dynamics and demography of the Sitka mouse, Peromyscus keeni sitkensis, were studied by mark-recapture live-trapping over a 4-year period in four floodplain and upland forest habitats: old-growth Sitka spruce (Picea sitchensis) floodplain; red alder (Alnus rubra) floodplain; beaver-pond...

  2. SPRUCE Shrub-Layer Growth Assessments in S1-Bog Plots and SPRUCE Experimental Plots beginning in 2010

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanson, P.J.; Phillips, J.R.; Brice, D.J.

    This data set reports shrub layer growth assessments for the S1-Bog on the Marcell Experimental Forest in Minnesota from 2010 through 2017. Data were obtained by destructively harvesting two 0.25 m2 plots within defined plot areas of the S1-Bog or SPRUCE experimental plots. In 2015, SPRUCE plots 4, 6, 8, 10, 11, 13, 16, 17, 19 and 20 were enclosed in the SPRUCE enclosures. Prior to 2015 all data are for open ambient conditions. In early years a distinct hummock and a hollow sampling square were both collected, but in later years unsampled hollow areas became unavailable due to priormore » sampling or instrument installations. All vegetation material above the Sphagnum surface of the bog was clipped and transferred to plastic storage bags which were then frozen until the samples could be sorted. Sorting was done by species, tissue type (leaves vs. stems) and tissue age (current-year vs. older tissues).« less

  3. Distinguishing Bark Beetle-infested Vegetation by Tree Species Types and Stress Levels using Landsat Data

    NASA Astrophysics Data System (ADS)

    Sivanpillai, R.; Ewers, B. E.; Speckman, H. N.; Miller, S. N.

    2015-12-01

    In the Western United States, more than 3 million hectares of lodgepole pine forests have been impacted by the Mountain pine beetle outbreak, while another 166,000 hectares of spruce-fir forests have been attacked by Spruce beetle. Following the beetle attack, the trees lose their hydraulic conductivity thus altering their carbon and water fluxes. These trees go through various stages of stress until mortality, described by color changes in their needles prior to losing them. Modeling the impact of these vegetation types require thematically precise land cover data that distinguishes lodgepole pine and spruce-fir forests along with the stage of impact since the ecosystem fluxes are different for these two systems. However, the national and regional-scale land cover datasets derived from remotely sensed data do not have this required thematic precision. We evaluated the feasibility of multispectral data collected by Landsat 8 to distinguish lodgepole pine and spruce fir, and subsequently model the different stages of attack using field data collected in Medicine Bow National Forest (Wyoming, USA). Operational Land Imager, onboard Landsat 8 has more spectral bands and higher radiometric resolution (12 bit) in comparison to sensors onboard earlier Landsat missions which could improve the ability to distinguish these vegetation types and their stress conditions. In addition to these characteristics, its repeat coverage, rigorous radiometric calibration, wide swath width, and no-cost data provide unique advantages to Landsat data for mapping large geographic areas. Initial results from this study highlight the importance of SWIR bands for distinguishing different levels of stress, and the need for ancillary data for distinguishing species types. Insights gained from this study could lead to the generation of land cover maps with higher thematic precision, and improve the ability to model various ecosystem processes as a result of these infestations.

  4. Interspecific Competition and Trade-offs in Resource Allocation are the Key to Successful Growth of Seedlings of White Spruce (Picea glauca (Moench) Voss) at Subarctic Treelines in Warming Alaska.

    NASA Astrophysics Data System (ADS)

    Okano, K.; Bret-Harte, M. S.

    2015-12-01

    Alpine treelines in Alaska have advanced for the past 50 years in response to the recent climate warming. However, further increases in temperatures may cause treeline species drought stress and increase susceptibility to insect outbreaks and fire. Complex factors such as soil conditions and plant species composition also impact the growth of seedlings, which are essential to sustain boreal forests. Our goals were to assess 1) the current optimal elevation for the treeline species Picea glauca (white spruce) seedlings and how it is altered by climate change, and 2) their growth/survival strategies at each environmental site. We studied the growth response of spruce seedlings along an altitudinal gradient at 6 sites, consisting of tundra, forest, or transitional ecotone in Denali National Park and one forest site in Fairbanks, AK. In May 2012, four-month old seedlings were planted with or without naturally occurring plants to compare the presence or absence of the interspecific interaction. Summer temperatures were increased by one small greenhouse per site. Over 2 growing seasons, growth was measured non-destructively, and then the seedlings were harvested. Relative growth rate (RGR) in height was increased significantly as the altitude was increased. Elevated temperature increased height only in seedlings at a high-altitude forest. Seedlings with neighboring plants had a higher RGR in height than seedlings that had neighbors removed, while significantly wider diameters were measured from the seedlings without neighbors. A weak trend of declining diameter width with increasing altitudes was seen. Seedlings that grew taller did not grow their stems wider, indicating trade-offs in resource allocation. None of the altitudinal sites had a clear advantage for the growth of the seedlings. Habitat microclimate and the interaction with other species could be more important than the altitude or temperatures and hence, key to the survival and growth of spruce seedlings in this region.

  5. Influence of windthrows and tree species on forest soil plant biomass and carbon stocks

    NASA Astrophysics Data System (ADS)

    Veselinovic, B.; Hager, H.

    2012-04-01

    The role of forests has generally been recognized in climate change mitigation and adaptation strategies and policies (e.g. Kyoto Protocol within articles 3.3 and 3.4, RES-E Directive of EU, Country Biomass Action Plans etc.). Application of mitigation actions, to decrease of CO2-emissions and, as the increase of carbon(C)-stocks and appropriate GHG-accounting has been hampered due to a lack of reliable data and good statistical models for the factors influencing C-sequestration in and its release from these systems (e.g. natural and human induced disturbances). Highest uncertainties are still present for estimation of soil C-stocks, which is at the same time the second biggest C-reservoir on earth. Spruce monocultures have been a widely used management practice in central Europe during the past century. Such stands are in lower altitudes (e.g. submontane to lower montane elevation zone) and on heavy soils unstable and prone to disturbances, especially on blowdown. As the windthrow-areas act as CO2-source, we hypothesize that conversion to natural beech and oak forests will provide sustainable wood supply and higher stability of stands against blowdown, which simultaneously provides the long-term belowground C-sequestration. This work focuses on influence of Norway spruce, Common beech and Oak stands on belowground C-dynamics (mineral soil, humus and belowground biomass) taking into consideration the increased impact of windthrows on spruce monocultures as a result of climate change. For this purpose the 300-700m altitude and pseudogley (planosols/temporally logged) soils were chosen in order to evaluate long-term impacts of the observed tree species on belowground C-dynamics and human induced disturbances on secondary spruce stands. Using the false chronosequence approach, the C-pools have been estimated for different compartments and age classes. The sampling of forest floor and surface vegetation was done using 30x30 (homogenous plots) and 50x50cm (inhomogeneous plots) frame. It was distinguished between following fractions: fine/coarse roots ( than 2mm), woody debris (dead wood, branches and seeds), living vegetation (ground vegetation and its roots), litter (leaves fresh and decomposed until the stage where the basic form can still be recognized) and humus layer (more than 30% organic matter in the fine fraction). Mineral soil was sampled down to 1m depth. The C stocks for 60 and 100cm depth were evaluated. The data enable a good overview of allocation of organic C within the belowground compartments, and its dynamics over the stand development stages for the relevant tree species of the Northern Alpine Foothills. In addition, these data enable the simulation of the long-term development of the belowground biomass and C-stocks for the three different stand types (pure spruce stands, mixed beech-spruce stands and oak stands). These results enable improvement of the statistical models in relation to site factors or stocking tree species and serve herewith further, as a valuable decision support for the innovative forest management practices and ensure the accomplishment of ecological, social and economical services of forest ecosystems.

  6. Shoot water relations of mature black spruce families displaying a genotype x environment interaction in growth rate. II. Temporal trends and response to varying soil water conditions

    Treesearch

    John E. Major; Kurt H. Johnsen

    1999-01-01

    Pressure-volume curves and shoot water potentials were determined for black spruce (Picea mariana (Mill.) BSP) trees from four full-sib families at the Petawawa Research Forest, Ontario, Canada. Trees were sampled from a dry site in 1992 and from the dry site and a wet site in 1993. Modulus of elasticity (e ), osmotic potential at...

  7. Deposition of Mercury in Forests along a Montane Elevation Gradient.

    PubMed

    Blackwell, Bradley D; Driscoll, Charles T

    2015-05-05

    Atmospheric mercury (Hg) deposition varies along elevation gradients and is influenced by both orographic and biological factors. We quantified total Hg deposition over a 2 year period at 24 forest sites at Whiteface Mountain, NY, USA, that ranged from 450 to 1450 m above sea level and covered three distinct forest types: deciduous/hardwood forest (14.1 μg/m2-yr), spruce/fir forest (33.8 μg/m2-yr), and stunted growth alpine/fir forest (44.0 μg/m2-yr). Atmospheric Hg deposition increased with elevation, with the dominant deposition pathways shifting from litterfall in low-elevation hardwoods to throughfall in midelevation spruce/fir to cloudwater in high-elevation alpine forest. Soil Hg concentrations (ranging from 69 to 416 ng/g for the Oi/Oe and 72 to 598 ng/g for the Oa horizons) were correlated with total Hg deposition, but the weakness of the correlations suggests that additional factors such as climate and tree species also contribute to soil Hg accumulation. Meteorological conditions influenced Hg deposition pathways, as cloudwater Hg diminished in 2010 (dry conditions) compared to 2009 (wet conditions). However, the dry conditions in 2010 led to increased Hg dry deposition and subsequent significant increases in throughfall Hg fluxes compared to 2009. These findings suggest that elevation, forest characteristics, and meteorological conditions are all important drivers of atmospheric Hg deposition to montane forests.

  8. Biosynthesis of the Major Tetrahydroxystilbenes in Spruce, Astringin and Isorhapontin, Proceeds via Resveratrol and Is Enhanced by Fungal Infection1[W][OA

    PubMed Central

    Hammerbacher, Almuth; Ralph, Steven G.; Bohlmann, Joerg; Fenning, Trevor M.; Gershenzon, Jonathan; Schmidt, Axel

    2011-01-01

    Stilbenes are dibenzyl polyphenolic compounds produced in several unrelated plant families that appear to protect against various biotic and abiotic stresses. Stilbene biosynthesis has been well described in economically important plants, such as grape (Vitis vinifera), peanut (Arachis hypogaea), and pine (Pinus species). However, very little is known about the biosynthesis and ecological role of stilbenes in spruce (Picea), an important gymnosperm tree genus in temperate and boreal forests. To investigate the biosynthesis of stilbenes in spruce, we identified two similar stilbene synthase (STS) genes in Norway spruce (Picea abies), PaSTS1 and PaSTS2, which had orthologs with high sequence identity in sitka (Picea sitchensis) and white (Picea glauca) spruce. Despite the conservation of STS sequences in these three spruce species, they differed substantially from angiosperm STSs. Several types of in vitro and in vivo assays revealed that the P. abies STSs catalyze the condensation of p-coumaroyl-coenzyme A and three molecules of malonyl-coenzyme A to yield the trihydroxystilbene resveratrol but do not directly form the dominant spruce stilbenes, which are tetrahydroxylated. However, in transgenic Norway spruce overexpressing PaSTS1, significantly higher amounts of the tetrahydroxystilbene glycosides, astringin and isorhapontin, were produced. This result suggests that the first step of stilbene biosynthesis in spruce is the formation of resveratrol, which is further modified by hydroxylation, O-methylation, and O-glucosylation to yield astringin and isorhapontin. Inoculating spruce with fungal mycelium increased STS transcript abundance and tetrahydroxystilbene glycoside production. Extracts from STS-overexpressing lines significantly inhibited fungal growth in vitro compared with extracts from control lines, suggesting that spruce stilbenes have a role in antifungal defense. PMID:21865488

  9. Biosynthesis of the major tetrahydroxystilbenes in spruce, astringin and isorhapontin, proceeds via resveratrol and is enhanced by fungal infection.

    PubMed

    Hammerbacher, Almuth; Ralph, Steven G; Bohlmann, Joerg; Fenning, Trevor M; Gershenzon, Jonathan; Schmidt, Axel

    2011-10-01

    Stilbenes are dibenzyl polyphenolic compounds produced in several unrelated plant families that appear to protect against various biotic and abiotic stresses. Stilbene biosynthesis has been well described in economically important plants, such as grape (Vitis vinifera), peanut (Arachis hypogaea), and pine (Pinus species). However, very little is known about the biosynthesis and ecological role of stilbenes in spruce (Picea), an important gymnosperm tree genus in temperate and boreal forests. To investigate the biosynthesis of stilbenes in spruce, we identified two similar stilbene synthase (STS) genes in Norway spruce (Picea abies), PaSTS1 and PaSTS2, which had orthologs with high sequence identity in sitka (Picea sitchensis) and white (Picea glauca) spruce. Despite the conservation of STS sequences in these three spruce species, they differed substantially from angiosperm STSs. Several types of in vitro and in vivo assays revealed that the P. abies STSs catalyze the condensation of p-coumaroyl-coenzyme A and three molecules of malonyl-coenzyme A to yield the trihydroxystilbene resveratrol but do not directly form the dominant spruce stilbenes, which are tetrahydroxylated. However, in transgenic Norway spruce overexpressing PaSTS1, significantly higher amounts of the tetrahydroxystilbene glycosides, astringin and isorhapontin, were produced. This result suggests that the first step of stilbene biosynthesis in spruce is the formation of resveratrol, which is further modified by hydroxylation, O-methylation, and O-glucosylation to yield astringin and isorhapontin. Inoculating spruce with fungal mycelium increased STS transcript abundance and tetrahydroxystilbene glycoside production. Extracts from STS-overexpressing lines significantly inhibited fungal growth in vitro compared with extracts from control lines, suggesting that spruce stilbenes have a role in antifungal defense.

  10. Photo guide for appraising downed woody fuels in Montana forests: lodgepole pine and Engelmann spruce - subalpine fir cover types

    Treesearch

    William C. Fischer

    1981-01-01

    Two series of color photographs show different levels of downed woody material resulting from natural processes in two forest cover types in Montana. Each photo is supplemented by fuel inventory data and potential fire· behavior ratings.

  11. Research at the Institute of Forest Genetics, Rhinelander, Wisconsin.

    Treesearch

    Richard M. Jeffers

    1971-01-01

    Reports research at the Forest Genetics Institute in Rhinelander, Wisconsin, since its beginning in 1957. Describes the physical plant, study objectives, and work program. The latter includes studies of seed source, inheritance in white spruce, disease and insect resistance, interspecific hybridization, radiation genetics and radiobiology, vegetative propagation,...

  12. CARBON MONOXIDE FLUXES OF DIFFERENT SOIL LAYERS IN UPLAND CANADIAN BOREAL FORESTS

    EPA Science Inventory

    Dark or low-light carbon monoxide fluxes at upland Canadian boreal forest sites were measured on-site with static chambers and with a laboratory incubation technique using cores from different depths at the same sites. Three different upland black spruce sites, burned in 1987,199...

  13. Linking climate and environmental factors to the recent and surprising growth increase of red spruce trees across the northeastern US

    NASA Astrophysics Data System (ADS)

    Kosiba, A. M.; Schaberg, P. G.; Rayback, S. A.; Hawley, G. J.

    2016-12-01

    Recent investigations have uncovered an unanticipated trend: red spruce (Picea rubens Sarg.) trees in the northeastern US are undergoing a marked surge in growth. This discovery stands in contrast to the declines in growth and vigor for red spruce that were documented in the second half of the 20th century and quantitatively attributed to acid deposition-induced calcium depletion. Further, predictions of potential habitat due to climate change depict red spruce habitat constricting from low elevations and latitudes. Considering these conflicting findings, we asked: what factors are most likely stimulating growth increases for red spruce trees? Here we use a uniquely large and both spatially- and temporally-explicit tree ring dataset to assess changes in red spruce growth over time. We compare patterns in growth to local weather data, atmospheric deposition rates, and other environmental and forest-stand metrics, including nutrient soil status and buffering capacity. These results allow us to model areas in the region where we predict similar growth increases for red spruce trees. Through this study, we suggest that this temperate conifer may be uniquely posed to benefit from a lengthened functional growing season, increased annual temperatures, particularly in winter, and decreased atmospheric pollution levels that proved problematic in the past.

  14. SPRUCE experiment data infrastructure

    NASA Astrophysics Data System (ADS)

    Krassovski, M.; Hanson, P. J.; Boden, T.; Riggs, J.; Nettles, W. R.; Hook, L. A.

    2013-12-01

    The Carbon Dioxide Information Analysis Center (CDIAC) at Oak Ridge National Laboratory (ORNL), USA has provided scientific data management support for the US Department of Energy and international climate change science since 1982. Among the many data activities CDIAC performs are design and implementation of the data systems. One current example is the data system and network for SPRUCE experiment. The SPRUCE experiment (http://mnspruce.ornl.gov) is the primary component of the Terrestrial Ecosystem Science Scientific Focus Area of ORNL's Climate Change Program, focused on terrestrial ecosystems and the mechanisms that underlie their responses to climatic change. The experimental work is to be conducted in a bog forest in northern Minnesota, 40 km north of Grand Rapids, in the USDA Forest Service Marcell Experimental Forest (MEF). The site is located at the southern margin of the boreal peatland forest. Experimental work in the 8.1-ha S1 bog will be a climate change manipulation focusing on the combined responses to multiple levels of warming at ambient or elevated CO2 (eCO2) levels. The experiment provides a platform for testing mechanisms controlling the vulnerability of organisms, biogeochemical processes and ecosystems to climatic change (e.g., thresholds for organism decline or mortality, limitations to regeneration, biogeochemical limitations to productivity, the cycling and release of CO2 and CH4 to the atmosphere). The manipulation will evaluate the response of the existing biological communities to a range of warming levels from ambient to +9°C, provided via large, modified open-top chambers. The ambient and +9°C warming treatments will also be conducted at eCO2 (in the range of 800 to 900 ppm). Both direct and indirect effects of these experimental perturbations will be analyzed to develop and refine models needed for full Earth system analyses. SPRUCE provides wide range continuous and discrete measurements. To successfully manage SPRUCE data flow and support climate change research, CDIAC has designed flexible data collection system using proven network technologies and taking advantage of existing software components. The SPRUCE data system comprised primarily of a set of network components, relational database, a web server to monitor data collection status, FTP server and replication/backup arrangement. Later the data interface on the existing website will be expanded to allow users to query the SPRUCE collection in a variety of ways and then subset, visualize and download the data. From the perspective of data stewardship, on the other hand, this system is designed for CDIAC to easily control database content, automate data movement, track data provenance, manage metadata content, and handle additions and corrections. In this presentation, we share our approaches to meet the challenges of designing and constructing data system for managing sources of high volume in situ observations in a remote location. It will demonstrate the dataflow starting from the sensors and ending at the archiving/distribution points, discuss types of hardware and software used, and examine considerations that were used to choose them.

  15. Postglacial vegetation history of the Kachemak Bay area, Cook Inlet, south-central Alaska: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1998

    USGS Publications Warehouse

    Ager, Thomas A.

    2000-01-01

    Pollen records from two sites on the north shore of Kachemak Bay, south-central Alaska, provide the first radiocarbon-dated histories of postglacial vegetation development for southern Cook Inlet. During the late Wisconsin glacial interval, glaciers covered most of Cook Inlet. Deglaciation of Kachemak Bay began prior to 13,000 yr B.P. Pollen evidence indicates that a pioneering herbaceous tundra began to develop by 12,800 yr B.P., but was soon replaced by a shrub tundra of dwarf birch (Betula), Ericales (Ericaceae and Empetrum) and willows (Salix).By 9,500 yr B.P., a shrub-dominated vegetation of alders (Alnus) and willows, with some deciduous trees (Populus spp.) quickly developed and persisted until late Holocene time. By about 4,000–3,800 yr B.P., spruce trees (Picea glauca and (or) P. mariana) from the interior boreal forests reached the northern Kachemak Bay area from upper Cook Inlet and began to displace the alder-dominated vegetation. A coastal forest of Sitka spruce (Picea sitchensis) began to colonize Kachemak Bay more recently, about 1,650 yr B.P. (minimum age), apparently from sources in Prince William Sound to the east. Where Sitka spruce came into proximity with boreal white spruce (Picea glauca), hybridization occurred, ultimately influencing the spruce forests over a large area of the Kenai Lowland. Some key findings of this study are: (1) the Kachemak Bay-area pollen records do not display persuasive evidence for a “Younger Dryas” cold, dry interval ca. 11,000–10,000 yr B.P. that has been reported from pollen records on Kodiak Island (Gulf of Alaska) and Pleasant Island (southeastern Alaska); (2) at least one species of alder may have survived in refugia in south-central Alaska during the last glacial interval; (3) coastal forests appear to be still migrating west along the coast of south-central Alaska, but their spread northward is being limited by drier, colder winter climates; (4) the mountainous topography of south-central Alaska, coupled with varying degrees of maritime climate influence, create complex patterns of climates and vegetation in the region, in both the past and present.

  16. Tropospheric ozone fluxes in Norway spruce forest during the transition period from autumn to winter

    NASA Astrophysics Data System (ADS)

    Juran, Stanislav; Fares, Silvano; Zapletal, Miloš; Cudlín, Pavel; Večeřa, Zbyněk; Urban, Otmar

    2017-04-01

    Norway spruce exhibits seasonal variations in stomatal conductance and photosynthetic activity typical for overwintering plants, with a decline during autumn and a complete recovery during spring. We investigated ozone fluxes during this transient period (November 2016). Fluxes of tropospheric ozone, the major phytotoxic near-ground pollutant causing injuries to plant tissues, were measured at Bily Kriz experimental station in Beskydy Mountains, the Czech Republic. Dry chemiluminescence fast-response ozone sensor coupled with sonic anemometer was used to measure fast fluctuations in ozone concentration and three-dimensional wind speed, respectively. Apart from this eddy covariance technique, within-canopy ozone concentration gradient was simultaneously measured by UV-absorption based slow-response ozone analysers. Ozone fluxes were subsequently modelled by an Inverse Lagrangian Transport Model (ILTM). A comparison of measured and calculated fluxes is thus available. Moreover, stomatal ozone flux was calculated based on Evaporative/Resistive method assuming stomata are the most relevant sink in the spruce forest. The low NOx concentration throughout the year and low concentrations of volatile organic compounds (VOCs) during the transition period led to hypothesize that non-stomatal flux here estimated by difference between total ozone flux and stomatal ozone flux is represented mainly by dry soil deposition and wet deposition during the snow period. We discuss here the ILTM parameterisation with comparison to measured ozone fluxes. Correct estimation of stomatal ozone flux is essential, especially in transition periods, where main scientific emphasis is put rarely. In addition, this research should help to develop metrics for ozone-risk assessment and advance our knowledge in biosphere-atmosphere exchange over Norway spruce forest. Acknowledgement This work was supported by the Ministry of Education, Youth and Sports within the National Programme for Sustainability (grant No. LO1415) and project CzeCOS (grant No. LM2015061).

  17. Ecophysiological importance of cloud immersion in a relic spruce-fir forest at elevational limits, southern Appalachian Mountains, USA.

    PubMed

    Berry, Z Carter; Smith, William K

    2013-11-01

    Climate warming predicts changes to the frequency and height of cloud-immersion events in mountain communities. Threatened southern Appalachian spruce-fir forests have been suggested to persist because of frequent periods of cloud immersion. These relic forests exist on only seven mountaintop areas, grow only above ca. 1,500 m elevation (maximum 2,037 m), and harbor the endemic Abies fraseri. To predict future distribution, we examined the ecophysiological effects of cloud immersion on saplings of A. fraseri and Picea rubens at their upper and lower elevational limits. Leaf photosynthesis, conductance, transpiration, xylem water potentials, and general abiotic variables were measured simultaneously on individuals at the top (1,960 m) and bottom (1,510 m) of their elevation limits on numerous clear and cloud-immersed days throughout the growing season. The high elevation sites had 1.5 as many cloud-immersed days (75 % of days) as the low elevation sites (56 % of days). Cloud immersion resulted in higher photosynthesis, leaf conductance, and xylem water potentials, particularly during afternoon measurements. Leaf conductance remained higher throughout the day with corresponding increases in photosynthesis and transpiration, despite low photon flux density levels, leading to an increase in water potentials from morning to afternoon. The endemic A. fraseri had a greater response in carbon gain and water balance in response to cloud immersion. Climate models predict warmer temperatures with a decrease in the frequency of cloud immersion for this region, leading to an environment on these peaks similar to elevations where spruce-fir communities currently do not exist. Because spruce-fir communities may rely on cloud immersion for improved carbon gain and water conservation, an upslope shift is likely if cloud ceilings rise. Their ultimate survival will likely depend on the magnitude of changes in cloud regimes.

  18. Heterotrophic cultivation of Auxenochlorella protothecoides using forest biomass as a feedstock for sustainable biodiesel production.

    PubMed

    Patel, Alok; Matsakas, Leonidas; Rova, Ulrika; Christakopoulos, Paul

    2018-01-01

    The aim of this work was to establish a process for the heterotrophic growth of green microalgae using forest biomass hydrolysates. To provide a carbon source for the growth of the green microalgae, two forest biomasses (Norway spruce and silver birch) were pretreated with a hybrid organosolv-steam explosion method, resulting in inhibitor-free pretreated solids with a high cellulose content of 77.9% w/w (birch) and 72% w/w (spruce). Pretreated solids were hydrolyzed using commercial cellulolytic enzymes to produce hydrolysate for the culture of algae. The heterotrophic growth of A. protothecoides was assessed using synthetic medium with glucose as carbon source, where the effect of sugar concentration and the carbon-to-nitrogen ratio were optimized, resulting in accumulation of lipids at 5.42 ± 0.32 g/L (64.52 ± 0.53% lipid content) after 5 days of culture on glucose at 20 g/L. The use of birch and spruce hydrolysates was favorable for the growth and lipid accumulation of the algae, resulting in lipid production of 5.65 ± 0.21 g/L (66 ± 0.33% lipid content) and 5.28 ± 0.17 g/L (63.08 ± 0.71% lipid content) when grown on birch and spruce, respectively, after only 120 h of cultivation. To the best of our knowledge, this is the first report of using organosolv pretreated wood biomass hydrolysates for the growth and lipid production of microalgae in the literature. The pretreatment process used in this study provided high saccharification of biomass without the presence of inhibitors. Moreover, the lipid profile of this microalga showed similar contents to vegetable oils which improve the biodiesel properties.

  19. Estimation of forest structural parameters using 5 and 10 meter SPOT-5 satellite data

    Treesearch

    Peter T. Wolter; Phillip A. Townsend; Brian R. Sturtevant

    2009-01-01

    Large areas of forest in the US and Canada are affected by insects and disease each year. Over the past century, outbreaks of the Eastern spruce budworm have become more frequent and severe. The notion of designing a more pest resistant landscape through prescriptive management practices hinges on our ability to effectively model forest?insect dynamics at regional...

  20. Weed killers may be useful in reforesting old burns

    Treesearch

    A. F. Hough

    1950-01-01

    More than 6 million acres in the 12 Northeastern and Middle Atlantic States need to be reforested, according to Forest Service estimates. Yet many of the sites that need planting are rocky and steep and hard to plant. In many places there is a dense cover of grasses, weeds, and shrubby growth. Old burns in the northern hardwood-hemlock forests and spruce-fir forests...

  1. The pollen record of a 20th century spruce beetle (Dendroctonus rufipennis) outbreak in a Colorado subalpine forest, USA

    Treesearch

    R. Scott Anderson; Susan J. Smith; Ann M. Lynch; Brian W. Geils

    2010-01-01

    The frequency and intensity of ecosystem disturbance, including outbreaks of forest insects and forest fires, is expected to increase in the future as a result of higher temperatures and prolonged drought. While many studies have concentrated on the future climatic impacts on fire, little is known about the impact of future climate on insect infestation....

  2. Identifying calcium sources at an acid deposition-impacted spruce forest: a strontium isotope, alkaline earth element multi-tracer approach

    Treesearch

    Thomas D. Bullen; Scott W. Bailey

    2005-01-01

    Depletion of calcium from forest soils has important implications for forest productivity and health. Ca is available to fine feeder roots from a number of soil organic and mineral sources. but identifying the primary source or changes of sources in response to environmental change is problematic. We used strontium isotope and alkaline earth element concentration...

  3. Forest canopy uptake of atmospheric nitrogen deposition at eastern U.S. conifer sites: Carbon storage implications?

    Treesearch

    Herman Sievering; Ivan Fernandez; John Lee; John Hom; Lindsey Rustad

    2000-01-01

    Dry deposition determinations, along with wet deposition and throughfall (TF) measurements, at a spruce fir forest in central Maine were used to estimate the effect of atmospherically deposited nitrogen (N) uptake on forest carbon storage. Using nitric acid and particulate N as well as TF ammonium and nitrate data, the growing season (May-October) net canopy uptake of...

  4. Impact of Market-Based Disturbance on the Composition of West Virginia's Forest Resource

    Treesearch

    William G. Luppold; John E. Baumgras; John E. Baumgras

    2000-01-01

    The eastern hardwood resource has been shaped by a combination of human and natural disturbances. This impact on the forest resources of West Virginia has been especially dramatic. This resource has changed from a virgin forest dominated white oak, chestnut, spruce, white pine, and hemlock in the late 19th century, to one dominated by red oak in the 1950's, to...

  5. Forest attributes and fuel loads of riparian vs. upland stands in mountain pine beetle infested watersheds, southern Rocky Mountains [Chapter 13

    Treesearch

    Kathleen A. Dwire; Roberto A. Bazan; Robert Hubbard

    2015-01-01

    Extensive outbreaks of mountain pine beetle (MPB), spruce beetle (SB), and other insects are altering forest stand structure throughout the Western United States, and thereby increasing the natural heterogeneity of fuel distribution. Riparian forests frequently occur as narrow linear features in the landscape mosaic and can contribute to the spatial complexity of...

  6. Population densities of northern Saw-whet Owls (Aegolius acadicus) in degraded boreal forests of the southern Appalachians

    Treesearch

    Timothy C. Milling; Matthew P. Rowe; Bennie L. Cockerel; Timothy A. Dellinger; Johnny B. Gailes; Christopher E. Hill

    1997-01-01

    A disjunct population of the Northern Saw-whet Owl (Aegolius acadicus) breeds in the montane spruce-fir forests of the southern Appalachian Mountains. These forests are listed as the second most endangered ecosystem in the United States, having suffered from logging and massive fir die-off from the exotic balsam woolly adelgid. We used audio...

  7. Control of depth to permafrost and soil temperature by the forest floor in black spruce/feathermoss communities.

    Treesearch

    C.T. Dyrness

    1982-01-01

    Changes in depth to permafrost and soil temperature were investigated for 4 years after treatment of the forest floor on small plots by fire and mechanical removal of half the forest floor layer and the entire layer. The only treatments to show a consistent, statistically significant effect were the mechanical removals. Fire treatments usually did not have a...

  8. Forests on drained agricultural peatland are potentially large sources of greenhouse gases - insights from a full rotation period simulation

    NASA Astrophysics Data System (ADS)

    He, Hongxing; Jansson, Per-Erik; Svensson, Magnus; Björklund, Jesper; Tarvainen, Lasse; Klemedtsson, Leif; Kasimir, Åsa

    2016-04-01

    The CoupModel was used to simulate a Norway spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring data a "vegetation fitted" model was obtained by which we were able to describe the fluxes and controlling factors over the 60 years. We discuss some conceptual issues relevant to improving the model in order to better understand peat soil simulations. However, the present model was able to describe the most important ecosystem dynamics such as the plant biomass development and GHG emissions. The GHG fluxes are composed of two important quantities, the spruce forest carbon (C) uptake, 413 g C m-2 yr-1 and the decomposition of peat soil, 399 g C m-2 yr-1. N2O emissions contribute to the GHG emissions by up to 0.7 g N m-2 yr-1, corresponding to 76 g C m-2 yr-1. The 60-year old spruce forest has an accumulated biomass of 16.0 kg C m-2 (corresponding to 60 kg CO2 m-2). However, over this period, 26.4 kg C m-2 (97 kg CO2eq m-2) has been added to the atmosphere, as both CO2 and N2O originating from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding CO2 to the atmosphere.

  9. Snow distribution and heat flow in the taiga

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sturm, M.

    1992-05-01

    The trees of the taiga intercept falling snow and cause it to become distributed in an uneven fashion. Around aspen and birch, cone-shaped accumulations form. Beneath large spruce trees, the snow cover is depleted, forming a bowl-shaped depression called a tree well. Small spruce trees become covered with snow, creating cavities that funnel cold air to the snow/ground interface. The depletion of snow under large spruce trees results in greater heat loss from the ground. A finite difference model suggests that heat flow from tree wells can be more than twice that of undisturbed snow. In forested watersheds, this increasemore » can be a significant percentage of the total winter energy exchange.« less

  10. Individual variation of sap-flow rate in large pine and spruce trees and stand transpiration: a pilot study at the central NOPEX site

    NASA Astrophysics Data System (ADS)

    Čermák, J.; Cienciala, E.; Kučera, J.; Lindroth, A.; Bednářová, E.

    1995-06-01

    Transpiration in a mixed old stand of sub-boreal forest in the Norunda region (central Sweden) was estimated on the basis of direct measurement of sap flow rate in 24 large Scots pine and Norway spruce trees in July and August 1993. Sap flow rate was measured using the trunk tissue heat balance method based on internal (electric) heating and sensing of temperature. Transpiration was only 0.7 mm day -1 in a relatively dry period in July (i.e. about 20% of potential evaporation) and substantially higher after a rainy period in August. The error of the estimates of transpiration was higher during a dry period (about 13% and 22% in pine and spruce, respectively) and significantly lower (about 9% in both species) during a period of sufficient water supply. Shallow-rooted spruce trees responded much faster to precipitation than deeply rooted pines.

  11. Reconciling multiple data sources to improve accuracy of large-scale prediction of forest disease incidence

    USGS Publications Warehouse

    Hanks, E.M.; Hooten, M.B.; Baker, F.A.

    2011-01-01

    Ecological spatial data often come from multiple sources, varying in extent and accuracy. We describe a general approach to reconciling such data sets through the use of the Bayesian hierarchical framework. This approach provides a way for the data sets to borrow strength from one another while allowing for inference on the underlying ecological process. We apply this approach to study the incidence of eastern spruce dwarf mistletoe (Arceuthobium pusillum) in Minnesota black spruce (Picea mariana). A Minnesota Department of Natural Resources operational inventory of black spruce stands in northern Minnesota found mistletoe in 11% of surveyed stands, while a small, specific-pest survey found mistletoe in 56% of the surveyed stands. We reconcile these two surveys within a Bayesian hierarchical framework and predict that 35-59% of black spruce stands in northern Minnesota are infested with dwarf mistletoe. ?? 2011 by the Ecological Society of America.

  12. Shoot water relations of mature black spruce families displaying a genotype × environment interaction in growth rate. III. Diurnal patterns as influenced by vapor pressure deficit and internal water status

    Treesearch

    John E. Major; Kurt H. Johnsen

    2001-01-01

    Pressure­volume curves were constructed and shoot water potentials measured for +20-year-old black spruce (Picea mariana (Mill.) BSP) trees from four full-sib families growing on a moist site and a dry site at the Petawawa Research Forest, Ontario, to determine whether differences in diurnal water relations traits were related to productivity. To...

  13. Vitality and chemistry of roots of red spruce in forest floors of stands with a gradient of soil Al/Ca ratios in the northeastern United States

    Treesearch

    Philip M. Wargo; Kristiina Vogt; Daniel Vogt; Quintaniay Holifield; Joel Tilley; Gregory Lawrence; Mark David

    2003-01-01

    Number of living root tips per branch, percent dead roots, percent mycorrhizae and mycorrhizal morphotype, response of woody roots to wounding and colonization by fungi, and concentrations of starch, soluble sugars, phenols, percent C and N and C/N ratio, and Al, Ca, Fe, K, Mg, Mn, and P were measured for 2 consecutive years in roots of red spruce (Picea...

  14. Spruce budworm feeding and oviposition are stimulated by monoterpenes in white spruce epicuticular waxes.

    PubMed

    Ennis, Darragh; Despland, Emma; Chen, Fei; Forgione, Pat; Bauce, Eric

    2017-02-01

    Monoterpenes, source of the distinctive odor of conifers, are generally considered plant defensive compounds. However, they are also known to act as long-range insect attractants, as they are volatile and permeate forest airspaces. Moreover, they are lipid soluble and can be absorbed into plant epicuticular waxes. We test their role in short-range host plant choice by both adult females and larvae of a folivorous forest pest (Choristoneura fumiferana). We conducted laboratory assays testing the responses of Eastern spruce budworm to an artificial monoterpene mix (α-pinene, β-pinene, limonene, myrcene) and to white spruce (Picea glauca) epicuticular waxes in closed arenas. Ovipositing females preferred filter paper discs treated with P. glauca waxes to controls, and preferred the waxes + monoterpenes treatment to waxes alone. However, females showed no preference between the monoterpene-treated disc and the control when presented without waxes. Feeding larvae prefered wax discs to control discs. They also consumed discs treated with realistic monoterpene concentrations and wax preferentially over wax-only discs, but showed no preference between extremely high monoterpene concentrations and wax-only controls. In an insect-free assay, P. glauca epicuticular wax decreased monoterpene volatilization. These results suggest that P. glauca waxes and realistic concentrations of monoterpenes are stimulatory to both egg-laying females and feeding larvae, and that their effects are synergistic. © 2015 Institute of Zoology, Chinese Academy of Sciences.

  15. Habitat Effects on the Breeding Performance of Three Forest-Dwelling Hawks.

    PubMed

    Björklund, Heidi; Valkama, Jari; Tomppo, Erkki; Laaksonen, Toni

    2015-01-01

    Habitat loss causes population declines, but the mechanisms are rarely known. In the European Boreal Zone, loss of old forest due to intensive forestry is suspected to cause declines in forest-dwelling raptors by reducing their breeding performance. We studied the boreal breeding habitat and habitat-associated breeding performance of the northern goshawk (Accipiter gentilis), common buzzard (Buteo buteo) and European honey buzzard (Pernis apivorus). We combined long-term Finnish bird-of-prey data with multi-source national forest inventory data at various distances (100-4000 m) around the hawk nests. We found that breeding success of the goshawk was best explained by the habitat within a 2000-m radius around the nests; breeding was more successful with increasing proportions of old spruce forest and water, and decreasing proportions of young thinning forest. None of the habitat variables affected significantly the breeding success of the common buzzard or the honey buzzard, or the brood size of any of the species. The amount of old spruce forest decreased both around goshawk and common buzzard nests and throughout southern Finland in 1992-2010. In contrast, the area of young forest increased in southern Finland but not around hawk nests. We emphasize the importance of studying habitats at several spatial and temporal scales to determine the relevant species-specific scale and to detect environmental changes. Further effort is needed to reconcile the socioeconomic and ecological functions of forests and habitat requirements of old forest specialists.

  16. Ponderosa pine, mixed conifer, and spruce-fir forests [Chapter 2

    Treesearch

    Michael A. Battaglia; Wayne D. Shepperd

    2007-01-01

    Before European settlement of the interior west of the United States, coniferous forests of this region were influenced by many disturbance regimes, primarily fires, insects, diseases, and herbivory, which maintained a diversity of successional stages and vegetative types across landscapes. Activities after settlement, such as fire suppression, grazing, and logging...

  17. Interactions between white spruce and shrubby alders at three boreal forest sites in Alaska.

    Treesearch

    Tricia L. Wurtz

    2000-01-01

    To document possible soil nitrogen mosaics before timber harvesting on three boreal forest sites in Alaska, maps of the distribution of understory green (Alnus crispa (Ait.) Pursh) and Sitka alder (A. sitchensis(Reg.) Rydb.) stems were made. Understory alders were regularly distributed throughout the northernmost site (Standard...

  18. Foliar chemistry of sugar maple: a regional view

    Treesearch

    Richard A. Hallett; Stephen B. Horsley; Robert P. Long; Scott W. Bailey; Thomas J. Hall

    1999-01-01

    Forest health and monitoring issues have become major focus of scientists and research institutions in Europe and North America during the last decade because of wide-spread forest decline symptoms in Europe, high elevation spruce/fir decline in eastern North America and sugar maple (Acer saccharum Marsh.) decline in Quebec, and the United States....

  19. Modeling biological disturbances in LANDIS: a module description and demonstration using spruce budworm

    Treesearch

    Brian R. Sturtevant; Eric J. Gustafson; Wei Li; Hong S. He

    2004-01-01

    Insects and diseases are common disturbance agents in forested ecosystems. Severe outbreaks can cause significant changes in tree species composition, age structure, and fuel conditions over broad areas. To investigate the role of biological disturbances in shaping forest landscapes over time, we constructed a new "biological disturbance agent" (BDA) module...

  20. Siberian Moth: Potential New Pest

    Treesearch

    Yuri Baranchikov; Michael Montgomery; Daniel Kucera

    1997-01-01

    The Siberian moth, Dendrolimus superans Butler (Family Lasiocampidae), is the most destructive defoliator of conifer forests in Northern Asia. Outbreaks defoliate millions of acres and occur at intervals of 8 to 11 years. The larvae feed on most conifers in the pine family, but outbreaks occur in fir, spruce, Siberian pine, and larch forests. The...

  1. Budworm damage in Canada: some observations on mortality

    Treesearch

    Thomas F. McLintock

    1951-01-01

    Information about spruce budworm damage in Canadian forests may be useful in reducing losses in Maine if the infestation becomes epidemic there. For this reason the Northeastern Forest Experiment Station has been studying the budworm epidemic in southwestern Quebec since 1945. Since trees are still dying, results of these studies must be considered indicative rather...

  2. Timberland resources of the Kenai Peninsula, Alaska, 1987.

    Treesearch

    Willem W.S. van Hees; Frederic R. Larson

    1991-01-01

    The 1987 inventory of the forest resources of the Kenai Peninsula was designed to assess the impact of the spruce beetle (Dendroctonus rufipennis (Kirby)) on the timberland component of the forest resource. Estimates of timberland area, volumes of timber, and growth and mortality of timber were developed. These estimates of timber resource...

  3. Temperature regimes and turbulent heat fluxes across a heterogeneous canopy in an Alaskan boreal forest

    USDA-ARS?s Scientific Manuscript database

    We evaluate local differences in thermal regimes and turbulent heat fluxes across the heterogeneous canopy of a black spruce boreal forest on discontinuous permafrost in interior Alaska. The data was taken during an intensive observing period in the summer of 2013 from two micrometeorological tower...

  4. Chemical changes in organic matter after fungal colonization in a nitrogen fertilized and unfertilized Norway spruce forest

    DOE PAGES

    Nicolas, Cesar; Almeida, Juan P.; Ellstrom, Magnus; ...

    2017-07-08

    Decomposition and transformation of organic matter (OM) in forest soils are conducted by the concomitant action of saprotrophic and mycorrhizal fungi. Here, we examine chemical changes in OM after fungal colonization in nitrogen fertilized and unfertilized soils from a Norway spruce forest. Sand-filled bags amended with composted maize leaves were placed in the forest soil and harvested after 17 months. Infrared and near edge X-ray absorption fine structure spectroscopies were used to study the chemical changes in the OM. Fungal community composition of the bags was also evaluated. The proportion of ectomycorrhizal fungi declined in the fertilized plots, but themore » overall fungal community composition was similar between N treatments. Decomposition of the OM was, independently of the N level or soil horizon, accompanied by an increase of C/N ratio of the mesh-bag content. Furthermore, the proportions of carboxylic compounds in the incubated OM increased in the mineral horizon, while heterocyclic-N compounds decreased, especially in unfertilized plots with higher N demand from the trees.« less

  5. Chemical changes in organic matter after fungal colonization in a nitrogen fertilized and unfertilized Norway spruce forest

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nicolas, Cesar; Almeida, Juan P.; Ellstrom, Magnus

    Decomposition and transformation of organic matter (OM) in forest soils are conducted by the concomitant action of saprotrophic and mycorrhizal fungi. Here, we examine chemical changes in OM after fungal colonization in nitrogen fertilized and unfertilized soils from a Norway spruce forest. Sand-filled bags amended with composted maize leaves were placed in the forest soil and harvested after 17 months. Infrared and near edge X-ray absorption fine structure spectroscopies were used to study the chemical changes in the OM. Fungal community composition of the bags was also evaluated. The proportion of ectomycorrhizal fungi declined in the fertilized plots, but themore » overall fungal community composition was similar between N treatments. Decomposition of the OM was, independently of the N level or soil horizon, accompanied by an increase of C/N ratio of the mesh-bag content. Furthermore, the proportions of carboxylic compounds in the incubated OM increased in the mineral horizon, while heterocyclic-N compounds decreased, especially in unfertilized plots with higher N demand from the trees.« less

  6. Early Stages Of Biome Shift in Boreal Alaska: Climate Sensitivity of Tree Growth and Accelerated Tree Mortality

    NASA Astrophysics Data System (ADS)

    Juday, G. P.; Grant, T.; Alix, C. M.; Spencer, D. L.; Beck, P. S.

    2012-12-01

    The boreal forest region of Alaska is characterized by a major east-west climate gradient, in addition to a widely appreciated north-south gradient. Low elevations of the eastern and central Interior experience warm summer temperatures and low annual precipitation, while coastal western Alaska has cool summer temperatures and greater precipitation. In the Interior the four dominant tree species of white and black spruce, aspen, and Alaska birch on low elevation sites nearly all register a strong negative radial growth relationship to summer temperatures, concentrated in May and July. Precipitation, particularly in late winter and midsummer, plays a supplemental role as a positive factor in growth. Floodplain white spruce along the Yukon and Kuskokwim Rivers transition from negative temperature response to positive response in western Alaska near the tree limit. Populations of white spruce on treeline sites display both negative growth response to July temperature and positive response to spring temperatures, with the negative response dominant in the east and the positive response dominant in the west. Across boreal Alaska summer temperatures increased abruptly in 1974, and have remained at historically high levels since. Correspondingly, climatic favorability for radial growth of Interior trees on most low elevation sites has been at extreme low levels particularly in the 21st century. Satellite-based NDVI coverage confirms that forest growth reduction is widespread in boreal Alaska since the 1980s. Defoliating and wood boring insects have reached outbreak population levels across most of boreal Alaska, partly from release of direct temperature control on the insects and partly from increased tree host susceptibility. Major outbreak species include aspen leaf miner, spruce engraver beetle, and spruce budworm. About a dozen tall willow species have been subjected to widespread attack by willow leaf blotch miner, and a new disease and defoliating insect have spread rapidly in alder shrubs, so nearly all woody species face health challenges. Temperatures and precipitation on many Interior sites are now at or beyond tolerance limits for white spruce, aspen, and Alaska birch. Two episodes of acute drought injury were widespread in birch during the last decade. Deficits in climate predicted tree growth are synchronous with the major insect outbreaks as recorded in insect trapping records and aerial surveys of area affected. Over the past 25 years tree mortality of 50% or more occurred in nearly all long-term monitoring plots in mature stands on productive sites in the Interior, but to date trees have successfully regenerated on most disturbed sites. These environmental changes and tree responses, including opposite responses, are coherent, and consistent with early stages of a biome shift eliminating boreal forest on dry Interior sites, and emergence of a new climate optimum zone in western Alaska currently only sparsely populated with forest.

  7. Thermal Acclimation of Photosynthesis and Respiration Differ Across Mature Conifer Species in a Boreal Forest Peatland

    NASA Astrophysics Data System (ADS)

    Dusenge, M. E.; Stinziano, J. R.; Warren, J.; Ward, E. J.; Wullschleger, S.; Hanson, P. J.; Way, D.

    2017-12-01

    Boreal forests are often assumed to be temperature-limited, and warming is therefore expected to stimulate their carbon uptake. However, much of our information on the ability of boreal conifers to acclimate photosynthesis and respiration to rising temperatures comes from seedlings. We measured net CO2 assimilation rates (A) and dark respiration (R) at 25 °C (A25 and R25) and at prevailing growth temperatures (Ag and Rg) in mature Picea mariana (spruce) and Larix laricina (tamarack) exposed to ambient, +2.25, +4.5, +6.75 and +9 °C warming treatments in open top chambers in the field at the SPRUCE experiment (MN, USA). In spruce, A25 and Ag were similar across plots in May and June. In August, spruce in warmer treatments had higher A25, an effect that was offset by warmer leaf temperatures in the Ag data. In tamarack, A25 was stimulated by warming in both June and August, an effect that was mainly offset by higher leaf temperatures when Ag was assessed in June, while in August, Ag was still slightly higher in the warmest treatments (+6.75 and +9) compared to the ambient plots. In spruce, R25 was enhanced in warm-grown trees in May, but was similar across treatments in June and August, indicating little acclimation of R. Rg slightly increased with warming treatments across the season in spruce. In contrast, R in tamarack thermally acclimated, as R25 decreased with warming. But while this acclimation generated homeostatic Rg in June, Rg in August was still highest in the warmest treatments. Our work suggests that the capacity for thermal acclimation in both photosynthesis and respiration varies among boreal tree species, which may lead to shifts in the performance of these species as the climate warms.

  8. The role of soil drainage class in carbon dioxide exchange and decomposition in boreal black spruce (Picea mariana) forest stands

    USGS Publications Warehouse

    Wickland, K.P.; Neff, J.C.; Harden, J.W.

    2010-01-01

    Black spruce (Picea mariana (Mill.) B.S.P.) forest stands range from well drained to poorly drained, typically contain large amounts of soil organic carbon (SOC), and are often underlain by permafrost. To better understand the role of soil drainage class in carbon dioxide (CO2) exchange and decomposition, we measured soil respiration and net CO2 fluxes, litter decomposition and litterfall rates, and SOC stocks above permafrost in three Alaska black spruce forest stands characterized as well drained (WD), moderately drained (MD), and poorly drained (PD). Soil respiration and net CO2 fluxes were not significantly different among sites, although the relation between soil respiration rate and temperature varied with site (Qw: WD > MD > PD). Annual estimated soil respiration, litter decomposition, and groundcover photosynthesis were greatest at PD. These results suggest that soil temperature and moisture conditions in shallow organic horizon soils at PD were more favorable for decomposition compared with the better drained sites. SOC stocks, however, increase from WD to MD to PD such that surface decomposition and C storage are diametric. Greater groundcover vegetation productivity, protection of deep SOC by permafrost and anoxic conditions, and differences in fire return interval and (or) severity at PD counteract the relatively high near-surface decomposition rates, resulting in high net C accumulation.

  9. Bird conservation issues in high-elevation (red spruce-fraser fir-northern hardwood) forests of the southern Blue Ridge

    Treesearch

    William C. Hunter

    2010-01-01

    The highest elevations in North America east of the Mississippi River are in the southern Blue Ridge of Virginia, North Carolina, and Tennessee. This area supports fauna and flora more characteristic of Canada than anywhere else in the southeast United States. The high-elevation forests are within the High Peaks Region to distinguish them from similar forests of the...

  10. Assessing urban forest effects and values, Casper's urban forest

    Treesearch

    David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

    2006-01-01

    An analysis of trees in Casper, WY reveals that this city has about 123,000 trees with canopies that cover 8.9 percent of the area. The most common tree species are plains cottonwood, blue spruce, and American elm. The urban forest currently store about 37,000 tons of carbon valued at $689,000. In addition, these trees remove about 1,200 tons of carbon per year ($22,...

  11. Small mammal habitat associations in poletimber and sawtimber stands of four forest cover types

    Treesearch

    Richard M. DeGraaf; Dana P. Snyder; Barbara J. Hill

    1991-01-01

    Small mammal distribution was examined in poletimber and sawtimber stands of four forest cover types in northern New England: northern hardwoods, red maple, balsam fir, and red spruce-balsam fir. During 1980 and 1981, eight stands on the White Mountain National Forest, NH, were sampled with four trap types (three sizes of snap traps and one pit-fall) for 16 000 trap-...

  12. Contrasts in carbon and nitrogen ecosystem budgets in adjacent Norway spruce and Appalachian hardwood watersheds in the Fernow Experimental Forest, West Virginia

    Treesearch

    Charlene Kelly; Stephen Schoenholtz; Mary Beth Adams

    2011-01-01

    We constructed watershed mass-balance budgets of carbon (C) and nitrogen (N) and measured seasonal net N mineralization in an attempt to account for nearly 40 years of large discrepancies in stream NO3-N export in two adjacent, gauged watersheds at the U.S. Department of Agriculture Forest Service's Fernow Experimental Forest, WV. These...

  13. Forest residues in hemlock-spruce forests of the Pacific Northwest and Alaska: a state-of-knowledge review with recommendations for residue management.

    Treesearch

    Robert H. Ruth; A.S. Harris

    1975-01-01

    The forest manager must balance all the interacting and often conflicting factors influencing residue management and decide on the best course of action. He needs to determine optimum volume, size, and arrangement of residues to leave on an area after logging, then to select the harvesting methods and residue management alternatives that best provide these conditions....

  14. Charcoal Reflectance Reveals Early Holocene Boreal Deciduous Forests Burned at High Intensities

    PubMed Central

    Hudspith, Victoria A.; Belcher, Claire M.; Kelly, Ryan; Hu, Feng Sheng

    2015-01-01

    Wildfire size, frequency, and severity are increasing in the Alaskan boreal forest in response to climate warming. One of the potential impacts of this changing fire regime is the alteration of successional trajectories, from black spruce to mixed stands dominated by aspen, a vegetation composition not experienced since the early Holocene. Such changes in vegetation composition may consequently alter the intensity of fires, influencing fire feedbacks to the ecosystem. Paleorecords document past wildfire-vegetation dynamics and as such, are imperative for our understanding of how these ecosystems will respond to future climate warming. For the first time, we have used reflectance measurements of macroscopic charcoal particles (>180μm) from an Alaskan lake-sediment record to estimate ancient charring temperatures (termed pyrolysis intensity). We demonstrate that pyrolysis intensity increased markedly from an interval of birch tundra 11 ky ago (mean 1.52%Ro; 485°C), to the expansion of trees on the landscape ∼10.5 ky ago, remaining high to the present (mean 3.54%Ro; 640°C) irrespective of stand composition. Despite differing flammabilities and adaptations to fire, the highest pyrolysis intensities derive from two intervals with distinct vegetation compositions. 1) the expansion of mixed aspen and spruce woodland at 10 cal. kyr BP, and 2) the establishment of black spruce, and the modern boreal forest at 4 cal. kyr BP. Based on our analysis, we infer that predicted expansion of deciduous trees into the boreal forest in the future could lead to high intensity, but low severity fires, potentially moderating future climate-fire feedbacks. PMID:25853712

  15. Charcoal reflectance reveals early holocene boreal deciduous forests burned at high intensities.

    PubMed

    Hudspith, Victoria A; Belcher, Claire M; Kelly, Ryan; Hu, Feng Sheng

    2015-01-01

    Wildfire size, frequency, and severity are increasing in the Alaskan boreal forest in response to climate warming. One of the potential impacts of this changing fire regime is the alteration of successional trajectories, from black spruce to mixed stands dominated by aspen, a vegetation composition not experienced since the early Holocene. Such changes in vegetation composition may consequently alter the intensity of fires, influencing fire feedbacks to the ecosystem. Paleorecords document past wildfire-vegetation dynamics and as such, are imperative for our understanding of how these ecosystems will respond to future climate warming. For the first time, we have used reflectance measurements of macroscopic charcoal particles (>180μm) from an Alaskan lake-sediment record to estimate ancient charring temperatures (termed pyrolysis intensity). We demonstrate that pyrolysis intensity increased markedly from an interval of birch tundra 11 ky ago (mean 1.52%Ro; 485°C), to the expansion of trees on the landscape ~10.5 ky ago, remaining high to the present (mean 3.54%Ro; 640°C) irrespective of stand composition. Despite differing flammabilities and adaptations to fire, the highest pyrolysis intensities derive from two intervals with distinct vegetation compositions. 1) the expansion of mixed aspen and spruce woodland at 10 cal. kyr BP, and 2) the establishment of black spruce, and the modern boreal forest at 4 cal. kyr BP. Based on our analysis, we infer that predicted expansion of deciduous trees into the boreal forest in the future could lead to high intensity, but low severity fires, potentially moderating future climate-fire feedbacks.

  16. Field measurements of dry deposition to spruce foliage and petri dishes in the Black Forest, F.R.G.

    USGS Publications Warehouse

    Shanley, J.B.

    1989-01-01

    Dry deposition fluxes Ca2+, Mg2+, K+, Mn2+, Pb2+ and SO42- to spruce foliage and petri dishes were measured in two high-elevation sites (>900 m) in the southern Black Forest, F.R.G., during 12 periods (2-7 days, each) from mid-September to mid-November, 1983, In situ extraction of deposited material from small spruce branches allowed repeated use of the same foliar collecting surfaces for a direct comparison of deposition between periods. Fluxes were corrected for leaching of internally cycled constituents using factors determined from serial extraction experiments. The ratio of flux to petri dishes vs foliage (P/F) was >1.0 for Ca2+, Pb2+ and SO42-, and somewhat 900 m) in the southern Black Forest, F.R.G., during 12 periods (2-7 days, each) from mid-September to mid-November, 1983. The ratio of flux to petri dishes vs foliage (P/F) was >1.0 for Ca2+, Pb2+, and SO42-, and somewhat <1.0 but more constant for Mg2+. Temporal variations in dry deposition fluxes at an exposed site near the industrialized Rhine Valley correlated with variations in total air particulate concentrations at a nearby air quality station. Deposition rates were comparable in magnitude but different in temporal pattern at a remote site in the Black Forest interior. Fluxes at each site reached a minimum during the period of 4-9 November when a regional air inversion confined pollutants to the Rhine Valley below the study sites. High fluxes accompanied the inversion break-up.

  17. AmeriFlux CA-Gro Ontario - Groundhog River, Boreal Mixedwood Forest.

    DOE Data Explorer

    McCaughey, Harry [Queen's University

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-Gro Ontario - Groundhog River, Boreal Mixedwood Forest.. Site Description - Groundhog River (FCRN or CCP site "ON-OMW") is situated in a typical boreal mixedwood forest in northeastern Ontario (48.217 degrees north and 82.156 degrees west) about 80 km southwest of Timmins in Reeves Twp. near the Groundhog River. Rowe (1972) places the site in the Missinaibi-Cabonga Section of the Boreal Forest Region. In terms of ecoregion and ecozone, the site is in the Lake Timiskaming Lowlands of the Boreal Shield. The forest developed after high-grade logging in the 1930's. The average age in 2013 is estimated at beteen 75 and 80 years. The forest is dominated by five species characteristic of Ontario boreal mixedwoods: trembling aspen (Populus tremuloides Michx.), black spruce (Picea mariana (Mill.) B.S.P.), white spruce (Picea glauca (Moench.) Voss.), white birch (Betula papyrifera Marsh.), and balsam fir (Abies balsamea (L.) Mill.). The surficial geology is a lacustrine deposit of varved or massive clays, silts and silty sands. The soil is an orthic gleysol with a soil moisture regime classified as fresh to very fresh. Plonski (1974) rates it as a site class 1. The topography is simple and flat with an overall elevation of 340 m ASL.

  18. Tree species partition N uptake by soil depth in boreal forests.

    PubMed

    Houle, D; Moore, J D; Ouimet, R; Marty, C

    2014-05-01

    It is recognized that the coexistence of herbaceous species in N-depleted habitats can be facilitated by N partitioning; however, the existence of such a phenomenon for trees has not yet been demonstrated. Here, we show from both foliage and soil 15N natural abundance values and from a 12-year in situ 15N addition experiment, that black spruce (Picea mariana) and jack pine (Pinus banksiana), two widespread species of the Canadian boreal forest, take up N at different depths. While black spruce takes up N from the organic soil, jack pine acquires it deeper within the highly N-depleted mineral soil. Systematic difference in foliar 15N natural abundance between the two species across seven sites distributed throughout the eastern Canadian boreal forest shows that N spatial partitioning is a widespread phenomenon. Distinct relationships between delta15N and N concentration in leaves of both species further emphasize their difference in N acquisition strategies. This result suggests that such complementary mechanisms of N acquisition could facilitate tree species coexistence in such N-depleted habitats and could contribute to the positive biodiversity-productivity relationship recently revealed for the eastern Canadian boreal forest, where jack pine is present. It also has implications for forest management and provides new insights to interpret boreal forest regeneration following natural or anthropogenic perturbations.

  19. Ecosystem development on terraces along the Kugururok River, northwest Alaska

    USGS Publications Warehouse

    Binkley, Dan; Suarez, F.; Stottlemyer, R.; Caldwell, B.

    1997-01-01

    Riverside terraces along the Kugururok River in the Noatak National Preserve provided an opportunity to study primary succession, considering general trends that apply across all terraces, and unique events that influence individual terraces. The 30-year-old willow/poplar (Salix spp., Populus balsamifera L.) terrace had no trees taller than 1.5 m; the abundant spruce trees were not tall enough to emerge from the canopy height of the willows and poplars, and moose (Alces alces [Clinton]) browsing limited the canopy height of these plants. The 75-year-old poplar/spruce (Picea glauca [Moench] Voss) terrace had a high density of poplars (> 1000/ha) and low density of spruce (125/ha); heavy browsing by moose reduced the density of poplar by about one-half. The removal of the poplar by moose in this stand resulted in sustained increases in growth of individual spruce trees. The 100-year-old younger spruce/poplar terrace had about twice as many spruce trees (1250/ha) as poplar trees (500/ha), and the spruce trees were larger on average than the poplar trees. In the 220+ year-old older spruce/poplar type, only a few poplars remained (about 25/ha), and the number of spruce trees (600/ha) was only half that of the younger stage, either from lower initial spruce density on this terrace, or increased mortality of spruce. The 240+ year-old spruce type was a second-generation forest, characterized by a high density (1950/ha) of small spruce trees, some of which were tilted, indicating discontinuous permafrost. Plant litterfall mass showed no strong trend with terrace age, although N content of litterfall appeared to decline by about 1/3 in the spruce-dominated stages. Fungal biomass increased with ecosystem age, whereas bacterial biomass and microfauna declined. We found no evidence of declining soil N supply in older stages, but fertilization experiments would be needed to determine if N limitation of productivity changed with ecosystem development. We conclude that the general successional trend of increased spruce dominance is robust for this location, but that unique events play important roles in determining tree densities and the timing of the shift in dominance from poplar to spruce. The arrival of moose in the 1970s accelerated dominance by spruce on young terraces.

  20. Comparing modern and presettlement forest dynamics of a subboreal wilderness: Does spruce budworm enhance fire risk?

    USGS Publications Warehouse

    Sturtevant, Brian R.; Miranda, Brian R.; Shinneman, Douglas J.; Gustafson, Eric J.; Wolter, Peter T.

    2012-01-01

    Insect disturbance is often thought to increase fire risk through enhanced fuel loadings, particularly in coniferous forest ecosystems. Yet insect disturbances also affect successional pathways and landscape structure that interact with fire disturbances (and vice-versa) over longer time scales. We applied a landscape succession and disturbance model (LANDIS-II) to evaluate the relative strength of interactions between spruce budworm (Choristoneura fumiferana) outbreaks and fire disturbances in the Boundary Waters Canoe Area (BWCA) in northern Minnesota (USA). Disturbance interactions were evaluated for two different scenarios: presettlement forests and fire regimes vs. contemporary forests and fire regimes. Forest composition under the contemporary scenario trended toward mixtures of deciduous species (primarily Betula papyrifera and Populus spp.) and shade-tolerant conifers (Picea mariana, Abies balsamea, Thuja occidentalis), with disturbances dominated by a combination of budworm defoliation and high-severity fires. The presettlement scenario retained comparatively more “big pines” (i.e., Pinus strobus, P. resinosa) and tamarack (L. laricina), and experienced less budworm disturbance and a comparatively less-severe fire regime. Spruce budworm disturbance decreased area burned and fire severity under both scenarios when averaged across the entire 300-year simulations. Contrary to past research, area burned and fire severity during outbreak decades were each similar to that observed in non-outbreak decades. Our analyses suggest budworm disturbances within forests of the BWCA have a comparatively weak effect on long-term forest composition due to a combination of characteristics. These include strict host specificity, fine-scaled patchiness created by defoliation damage, and advance regeneration of its primary host, balsam fir (A. balsamea) that allows its host to persist despite repeated disturbances. Understanding the nature of the three-way interaction between budworm, fire, and composition has important ramifications for both fire mitigation strategies and ecosystem restoration initiatives. We conclude that budworm disturbance can partially mitigate long-term future fire risk by periodically reducing live ladder fuel within the mixed forest types of the BWCA but will do little to reverse the compositional trends caused in part by reduced fire rotations.

  1. Interspecific variation in growth responses to tree size, competition and climate of western Canadian boreal mixed forests.

    PubMed

    Jiang, Xinyu; Huang, Jian-Guo; Cheng, Jiong; Dawson, Andria; Stadt, Kenneth J; Comeau, Philip G; Chen, Han Y H

    2018-08-01

    Tree growth of boreal forest plays an important role on global carbon (C) cycle, while tree growth in the western Canadian boreal mixed forests has been predicted to be negatively affected by regional drought. Individual tree growth can be controlled by many factors, such as competition, climate, tree size and age. However, information about contributions of different factors to tree growth is still limited in this region. In order to address this uncertainty, tree rings of two dominant tree species, trembling aspen (Populus tremuloides Michx.) and white spruce (Picea glauca (Moench.) Voss), were sampled from boreal mixed forest stands distributed across Alberta, Canada. Tree growth rates over different time intervals (10years interval, 1998-2007; 20years interval, 1988-2007; 30years interval, 1978-2007) were calculated to study the effects of different factors (tree size, competition, climate, and age) on tree growth. Results indicated that tree growth of two species were both primarily affected by competition or tree size, while climatic indices showed less effects on tree growth. Growth of trembling aspen was significantly affected by inter- and intraspecific competition, while growth of white spruce was primarily influenced by tree size, followed by competition. Positive relationship was found between growth of white spruce and competition index of coniferous group, suggesting an intraspecific mutualism mechanism within coniferous group. Our results further suggested that competition driven succession was the primary process of forest composition shift in the western Canadian boreal mixed forest. Although drought stress increased tree mortality, decline of stem density under climate change released competition stress of surviving trees, which in turn sustained growth of surviving trees. Therefore, climatic indices showed fewer effects on growth of dominant tree species compared to other factors in our study. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Morphological plasticity of ectomycorrhizal short roots in Betula sp and Picea abies forests across climate and forest succession gradients: its role in changing environments

    PubMed Central

    Ostonen, Ivika; Rosenvald, Katrin; Helmisaari, Heljä-Sisko; Godbold, Douglas; Parts, Kaarin; Uri, Veiko; Lõhmus, Krista

    2013-01-01

    Morphological plasticity of ectomycorrhizal (EcM) short roots (known also as first and second order roots with primary development) allows trees to adjust their water and nutrient uptake to local environmental conditions. The morphological traits (MTs) of short-living EcM roots, such as specific root length (SRL) and area, root tip frequency per mass unit (RTF), root tissue density, as well as mean diameter, length, and mass of the root tips, are good indicators of acclimation. We investigated the role of EcM root morphological plasticity across the climate gradient (48–68°N) in Norway spruce (Picea abies (L.) Karst) and (53–66°N) birch (Betula pendula Roth., B. pubescens Ehrh.) forests, as well as in primary and secondary successional birch forests assuming higher plasticity of a respective root trait to reflect higher relevance of that characteristic in acclimation process. We hypothesized that although the morphological plasticity of EcM roots is subject to the abiotic and biotic environmental conditions in the changing climate; the tools to achieve the appropriate morphological acclimation are tree species-specific. Long-term (1994–2010) measurements of EcM roots morphology strongly imply that tree species have different acclimation-indicative root traits in response to changing environments. Birch EcM roots acclimated along latitude by changing mostly SRL [plasticity index (PI) = 0.60], while spruce EcM roots became adjusted by modifying RTF (PI = 0.68). Silver birch as a pioneer species must have a broader tolerance to environmental conditions across various environments; however, the mean PI of all MTs did not differ between early-successional birch and late-successional spruce. The differences between species in SRL, and RTF, diameter, and length decreased southward, toward temperate forests with more favorable growth conditions. EcM root traits reflected root-rhizosphere succession across forest succession stages. PMID:24032035

  3. Morphological plasticity of ectomycorrhizal short roots in Betula sp and Picea abies forests across climate and forest succession gradients: its role in changing environments.

    PubMed

    Ostonen, Ivika; Rosenvald, Katrin; Helmisaari, Heljä-Sisko; Godbold, Douglas; Parts, Kaarin; Uri, Veiko; Lõhmus, Krista

    2013-01-01

    Morphological plasticity of ectomycorrhizal (EcM) short roots (known also as first and second order roots with primary development) allows trees to adjust their water and nutrient uptake to local environmental conditions. The morphological traits (MTs) of short-living EcM roots, such as specific root length (SRL) and area, root tip frequency per mass unit (RTF), root tissue density, as well as mean diameter, length, and mass of the root tips, are good indicators of acclimation. We investigated the role of EcM root morphological plasticity across the climate gradient (48-68°N) in Norway spruce (Picea abies (L.) Karst) and (53-66°N) birch (Betula pendula Roth., B. pubescens Ehrh.) forests, as well as in primary and secondary successional birch forests assuming higher plasticity of a respective root trait to reflect higher relevance of that characteristic in acclimation process. We hypothesized that although the morphological plasticity of EcM roots is subject to the abiotic and biotic environmental conditions in the changing climate; the tools to achieve the appropriate morphological acclimation are tree species-specific. Long-term (1994-2010) measurements of EcM roots morphology strongly imply that tree species have different acclimation-indicative root traits in response to changing environments. Birch EcM roots acclimated along latitude by changing mostly SRL [plasticity index (PI) = 0.60], while spruce EcM roots became adjusted by modifying RTF (PI = 0.68). Silver birch as a pioneer species must have a broader tolerance to environmental conditions across various environments; however, the mean PI of all MTs did not differ between early-successional birch and late-successional spruce. The differences between species in SRL, and RTF, diameter, and length decreased southward, toward temperate forests with more favorable growth conditions. EcM root traits reflected root-rhizosphere succession across forest succession stages.

  4. Size-mediated tree transpiration along soil drainage gradients in a boreal black spruce forest wildfire chronosequence.

    PubMed

    Angstmann, J L; Ewers, B E; Kwon, H

    2012-05-01

    Boreal forests are crucial to climate change predictions because of their large land area and ability to sequester and store carbon, which is controlled by water availability. Heterogeneity of these forests is predicted to increase with climate change through more frequent wildfires, warmer, longer growing seasons and potential drainage of forested wetlands. This study aims at quantifying controls over tree transpiration with drainage condition, stand age and species in a central Canadian black spruce boreal forest. Heat dissipation sensors were installed in 2007 and data were collected through 2008 on 118 trees (69 Picea mariana (Mill.) Britton, Sterns & Poggenb. (black spruce), 25 Populus tremuloides Michx. (trembling aspen), 19 Pinus banksiana Lamb. (jack pine), 3 Larix laricina (Du Roi) K. Koch (tamarack) and 2 Salix spp. (willow)) at four stand ages (18, 43, 77 and 157 years old) each containing a well- and poorly-drained stand. Transpiration estimates from sap flux were expressed per unit xylem area, J(S), per unit ground area, E(C) and per unit leaf area, E(L), using sapwood (A(S)) and leaf (A(L)) area calculated from stand- and species-specific allometry. Soil drainage differences in transpiration were variable; only the 43- and 157-year-old poorly-drained stands had ∼ 50% higher total stand E(C) than well-drained locations. Total stand E(C) tended to decrease with stand age after an initial increase between the 18- and 43-year-old stands. Soil drainage differences in transpiration were controlled primarily by short-term physiological drivers such as vapor pressure deficit and soil moisture whereas stand age differences were controlled by successional species shifts and changes in tree size (i.e., A(S)). Future predictions of boreal climate change must include stand age, species and soil drainage heterogeneity to avoid biased estimates of forest water loss and latent energy exchanges.

  5. Development of spatial scaling technique of forest health sample point information

    NASA Astrophysics Data System (ADS)

    Lee, J.; Ryu, J.; Choi, Y. Y.; Chung, H. I.; Kim, S. H.; Jeon, S. W.

    2017-12-01

    Most forest health assessments are limited to monitoring sampling sites. The monitoring of forest health in Britain in Britain was carried out mainly on five species (Norway spruce, Sitka spruce, Scots pine, Oak, Beech) Database construction using Oracle database program with density The Forest Health Assessment in GreatBay in the United States was conducted to identify the characteristics of the ecosystem populations of each area based on the evaluation of forest health by tree species, diameter at breast height, water pipe and density in summer and fall of 200. In the case of Korea, in the first evaluation report on forest health vitality, 1000 sample points were placed in the forests using a systematic method of arranging forests at 4Km × 4Km at regular intervals based on an sample point, and 29 items in four categories such as tree health, vegetation, soil, and atmosphere. As mentioned above, existing researches have been done through the monitoring of the survey sample points, and it is difficult to collect information to support customized policies for the regional survey sites. In the case of special forests such as urban forests and major forests, policy and management appropriate to the forest characteristics are needed. Therefore, it is necessary to expand the survey headquarters for diagnosis and evaluation of customized forest health. For this reason, we have constructed a method of spatial scale through the spatial interpolation according to the characteristics of each index of the main sample point table of 29 index in the four points of diagnosis and evaluation report of the first forest health vitality report, PCA statistical analysis and correlative analysis are conducted to construct the indicators with significance, and then weights are selected for each index, and evaluation of forest health is conducted through statistical grading.

  6. The joint influence of photoperiod and temperature during growth cessation and development of dormancy in white spruce (Picea glauca).

    PubMed

    Hamilton, Jill A; El Kayal, Walid; Hart, Ashley T; Runcie, Daniel E; Arango-Velez, Adriana; Cooke, Janice E K

    2016-11-01

    Timely responses to environmental cues enable the synchronization of phenological life-history transitions essential for the health and survival of north-temperate and boreal tree species. While photoperiodic cues will remain persistent under climate change, temperature cues may vary, contributing to possible asynchrony in signals influencing developmental and physiological transitions essential to forest health. Understanding the relative contribution of photoperiod and temperature as determinants of the transition from active growth to dormancy is important for informing adaptive forest management decisions that consider future climates. Using a combination of photoperiod (long = 20 h or short = 8 h day lengths) and temperature (warm = 22 °C/16 °C and cool = 8 °C/4 °C day/night, respectively) treatments, we used microscopy, physiology and modeling to comprehensively examine hallmark traits of the growth-dormancy transition-including bud formation, growth cessation, cold hardiness and gas exchange-within two provenances of white spruce [Picea glauca (Moench) Voss] spanning a broad latitude in Alberta, Canada. Following exposure to experimental treatments, seedlings were transferred to favorable conditions, and the depth of dormancy was assessed by determining the timing and ability of spruce seedlings to resume growth. Short photoperiods promoted bud development and growth cessation, whereas longer photoperiods extended the growing season through the induction of lammas growth. In contrast, cool temperatures under both photoperiodic conditions delayed bud development. Photoperiod strongly predicted the development of cold hardiness, whereas temperature predicted photosynthetic rates associated with active growth. White spruce was capable of attaining endodormancy, but its release was environmentally determined. Dormancy depth varied substantially across experimental treatments suggesting that environmental cues experienced within one season could affect growth in the following season, which is particularly important for a determinate species such as white spruce. The joint influence of these environmental cues points toward the importance of including local constant photoperiod and shifting temperature cues into predictive models that consider how climate change may affect northern forests. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Disentangling the effects of acidic air pollution, atmospheric CO2 , and climate change on recent growth of red spruce trees in the Central Appalachian Mountains.

    PubMed

    Mathias, Justin M; Thomas, Richard B

    2018-05-20

    In the 45 years after legislation of the Clean Air Act, there has been tremendous progress in reducing acidic air pollutants in the eastern United States, yet limited evidence exists that cleaner air has improved forest health. Here, we investigate the influence of recent environmental changes on the growth and physiology of red spruce (Picea rubens Sarg.) trees, a key indicator species of forest health, spanning three locations along a 100 km transect in the Central Appalachian Mountains. We incorporated a multiproxy approach using 75-year tree ring chronologies of basal tree growth, carbon isotope discrimination (∆ 13 C, a proxy for leaf gas exchange), and δ 15 N (a proxy for ecosystem N status) to examine tree and ecosystem level responses to environmental change. Results reveal the two most important factors driving increased tree growth since ca. 1989 are reductions in acidic sulfur pollution and increases in atmospheric CO 2 , while reductions in pollutant emissions of NO x and warmer springs played smaller, but significant roles. Tree ring ∆ 13 C signatures increased significantly since 1989, concurrently with significant declines in tree ring δ 15 N signatures. These isotope chronologies provide strong evidence that simultaneous changes in C and N cycling, including greater photosynthesis and stomatal conductance of trees and increases in ecosystem N retention, were related to recent increases in red spruce tree growth and are consequential to ecosystem recovery from acidic pollution. Intrinsic water use efficiency (iWUE) of the red spruce trees increased by ~51% across the 75-year chronology, and was driven by changes in atmospheric CO 2 and acid pollution, but iWUE was not linked to recent increases in tree growth. This study documents the complex environmental interactions that have contributed to the recovery of red spruce forest ecosystems from pervasive acidic air pollution beginning in 1989, about 15 years after acidic pollutants started to decline in the United States. © 2018 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  8. Upland Trees Contribute to Exchange of Nitrous Oxide (N2O) in Forest Ecosystems

    NASA Astrophysics Data System (ADS)

    Tian, H.; Thompson, R.; Canadell, J.; Winiwarter, W.; Machacova, K.; Maier, M.; Halmeenmäki, E.; Svobodova, K.; Lang, F.; Pihlatie, M.; Urban, O.

    2017-12-01

    The increase in atmospheric nitrous oxide (N2O) concentration contributes to the acceleration of the greenhouse effect. However, the role of trees in the N2O exchange of forest ecosystems is still an open question. While the soils of temperate and boreal forests were shown to be a natural source of N2O, trees have been so far overlooked in the forest N2O inventories. We determined N2O fluxes in common tree species of boreal and temperate forests: Scots pine (Pinus sylvestris), Norway spruce (Picea abies), downy and silver birch (Betula pubescens, B. pendula), and European beech (Fagus sylvatica). We investigated (1) whether these tree species exchange N2O with the atmosphere under natural field conditions, (2) how the tree N2O fluxes contribute to the forest N2O balance, and (3) whether these fluxes show seasonal dynamics. The studies were performed in a boreal forest (SMEAR II station, Finland; June 2014 - May 2015) and two temperate mountain forests (White Carpathians, Czech Republic; Black Forest, Germany; June and July 2015). Fluxes of N2O in mature tree stems and forest floor were measured using static chamber systems followed by chromatographic and photo-acoustic analyses of N2O concentration changes. Pine, spruce and birch trees were identified as net annual N2O sources. Spruce was found the strongest emitter (0.27 mg ha-1 h-1) amounting thus up to 2.5% of forest floor N2O emissions. All tree species showed a substantial seasonality in stem N2O flux that was related to their physiological activity and climatic variables. In contrast, stems of beech trees growing at soils consuming N2O may act as a substantial sink of N2O from the atmosphere. Consistent N2O consumption by tree stems ranging between -12.1 and -35.2 mg ha-1 h-1 and contributing by up to 3.4% to the forest floor N2O uptake is a novel finding in contrast to current studies presenting trees as N2O emitters. To understand these fluxes, N2O exchange of photoautotrophic organisms associated with beech bark (lichens, mosses and algae) was quantified. All the organisms were net N2O sinks at full rehydration with consumption rates comparable to stem consumption rates. All tree species studied contribute to N2O exchange in forest ecosystems and these fluxes have to be included in the forest N2O emission inventories.

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lawrence, G.B.; Fernandez, I.J.; Goltz, S.M.

    To provide information needed to assess the current and future status of spruce-fir forests in Maine, the Howland Integrated Forest Study (HIFS) was initiated in 1987 as part of the USDA Forest Service Forest Response Program, in conjunction with the establishment of a Mountain Cloud Chemistry Program (MCCP) monitoring site. Through this project, bulk and wet-only precipitation, dry deposition, throughfall and soil solution chemistry has been determined. This paper will focus on soil solution collected between May, 1988 and bulk precipitation collected from June through November, 1988.

  10. Climate-diameter growth relationships of black spruce and jack pine trees in boreal Ontario, Canada.

    PubMed

    Subedi, Nirmal; Sharma, Mahadev

    2013-02-01

    To predict the long-term effects of climate change - global warming and changes in precipitation - on the diameter (radial) growth of jack pine (Pinus banksiana Lamb.) and black spruce (Picea mariana [Mill.] B.S.P.) trees in boreal Ontario, we modified an existing diameter growth model to include climate variables. Diameter chronologies of 927 jack pine and 1173 black spruce trees, growing in the area from 47°N to 50°N and 80°W to 92°W, were used to develop diameter growth models in a nonlinear mixed-effects approach. Our results showed that the variables long-term average of mean growing season temperature, precipitation during wettest quarter, and total precipitation during growing season were significant (alpha = 0.05) in explaining variation in diameter growth of the sample trees. Model results indicated that higher temperatures during the growing season would increase the diameter growth of jack pine trees, but decrease that of black spruce trees. More precipitation during the wettest quarter would favor the diameter growth of both species. On the other hand, a wetter growing season, which may decrease radiation inputs, increase nutrient leaching, and reduce the decomposition rate, would reduce the diameter growth of both species. Moreover, our results indicated that future (2041-2070) diameter growth rate may differ from current (1971-2000) growth rates for both species, with conditions being more favorable for jack pine than black spruce trees. Expected future changes in the growth rate of boreal trees need to be considered in forest management decisions. We recommend that knowledge of climate-growth relationships, as represented by models, be combined with learning from adaptive management to reduce the risks and uncertainties associated with forest management decisions. © 2012 Blackwell Publishing Ltd.

  11. Survival and growth patterns of white spruce (Picea glauca [Moench] Voss) rangewide provenances and their implications for climate change adaptation

    PubMed Central

    Lu, Pengxin; Parker, William H; Cherry, Marilyn; Colombo, Steve; Parker, William C; Man, Rongzhou; Roubal, Ngaire

    2014-01-01

    Intraspecific assisted migration (ISAM) through seed transfer during artificial forest regeneration has been suggested as an adaptation strategy to enhance forest resilience and productivity under future climate. In this study, we assessed the risks and benefits of ISAM in white spruce based on long-term and multilocation, rangewide provenance test data. Our results indicate that the adaptive capacity and growth potential of white spruce varied considerably among 245 range-wide provenances sampled across North America; however, the results revealed that local populations could be outperformed by nonlocal ones. Provenances originating from south-central Ontario and southwestern Québec, Canada, close to the southern edge of the species' natural distribution, demonstrated superior growth in more northerly environments compared with local populations and performed much better than populations from western Canada and Alaska, United States. During the 19–28 years between planting and measurement, the southern provenances have not been more susceptible to freezing damage compared with local populations, indicating they have the potential to be used now for the reforestation of more northerly planting sites; based on changing temperature, these seed sources potentially could maintain or increase white spruce productivity at or above historical levels at northern sites. A universal response function (URF), which uses climatic variables to predict provenance performance across field trials, indicated a relatively weak relationship between provenance performance and the climate at provenance origin. Consequently, the URF from this study did not provide information useful to ISAM. The ecological and economic importance of conserving white spruce genetic resources in south-central Ontario and southwestern Québec for use in ISAM is discussed. PMID:25360273

  12. Survival and growth patterns of white spruce (Picea glauca [Moench] Voss) rangewide provenances and their implications for climate change adaptation.

    PubMed

    Lu, Pengxin; Parker, William H; Cherry, Marilyn; Colombo, Steve; Parker, William C; Man, Rongzhou; Roubal, Ngaire

    2014-06-01

    Intraspecific assisted migration (ISAM) through seed transfer during artificial forest regeneration has been suggested as an adaptation strategy to enhance forest resilience and productivity under future climate. In this study, we assessed the risks and benefits of ISAM in white spruce based on long-term and multilocation, rangewide provenance test data. Our results indicate that the adaptive capacity and growth potential of white spruce varied considerably among 245 range-wide provenances sampled across North America; however, the results revealed that local populations could be outperformed by nonlocal ones. Provenances originating from south-central Ontario and southwestern Québec, Canada, close to the southern edge of the species' natural distribution, demonstrated superior growth in more northerly environments compared with local populations and performed much better than populations from western Canada and Alaska, United States. During the 19-28 years between planting and measurement, the southern provenances have not been more susceptible to freezing damage compared with local populations, indicating they have the potential to be used now for the reforestation of more northerly planting sites; based on changing temperature, these seed sources potentially could maintain or increase white spruce productivity at or above historical levels at northern sites. A universal response function (URF), which uses climatic variables to predict provenance performance across field trials, indicated a relatively weak relationship between provenance performance and the climate at provenance origin. Consequently, the URF from this study did not provide information useful to ISAM. The ecological and economic importance of conserving white spruce genetic resources in south-central Ontario and southwestern Québec for use in ISAM is discussed.

  13. The timing and nature of Late Quaternary vegetation changes in the northern Great Plains, USA and Canada: a re-assessment of the spruce phase

    NASA Astrophysics Data System (ADS)

    Yansa, Catherine H.

    2006-02-01

    This paper revises the chronology for the northward migration of Picea glauca (white spruce) across the northern Great Plains, following the recession of the Laurentide Ice Sheet, and reinterprets the species composition and structure of the late-glacial vegetation on the basis of pollen and plant-macrofossil analysis. The timing of spruce migration is based on 26 14C ages obtained from Picea macrofossils. The date for the appearance of white spruce in southern South Dakota, USA, remains unchanged, 12,600 14C yr BP (ca 15,000 cal yr BP), but its arrival in southern Saskatchewan, Canada, by 10,300 14C yr BP (ca 12,100 cal yr BP) is about 1500 years later than previously estimated based on an organic sediment date. Picea glauca thus migrated northwards at an average rate of 0.38 km/ 14C year (0.30 km/calendar year), significantly slower than the previously published rate of 2 km/ 14C year. White spruce trees probably inhabited lake shorelines, whereas prairie, parkland, and boreal plants occupied both lowlands and uplands, forming an open white spruce parkland. This interpretation differs from a previous reconstruction of a boreal-type spruce forest and thus offers another paleoclimatic interpretation. Precipitation was probably low and summer temperatures relatively mild, averaging about 19 °C.

  14. Effect of wildfire and fireline construction on the annual depth of thaw in a black spruce permafrost forest in interior Alaska: a 36-year record of recovery

    Treesearch

    Leslie A. Viereck; Nancy R. Werdin-Pfisterer; Phyllis C. Adams; Kenji Yoshikawa

    2008-01-01

    Maximum thaw depths were measured annually in an unburned stand, a heavily burned stand, and a fireline in and adjacent to the 1971 Wickersham fire. Maximum thaw in the unburned black spruce stand ranged from 36 to 52 cm. In the burned stand, thaw increased each year to a maximum depth of 302 cm in 1995. In 1996, the entire layer of seasonal frost remained, creating a...

  15. SPRUCE Methylotrophic Methanogenesis in Sphagnum-dominated Peatland Soils – CH4 and CO2 Production in Laboratory Incubations

    DOE Data Explorer

    Zalman, Cassandra A.; Meade, N.; Chanton, J.; Kostka, J. E.; Bridgham, S. D.; Keller, J. K.

    2017-12-01

    This study investigated the potential for methylotrophic methanogenesis in three Sphagnum-dominated peatland soils in northern Minnesota. Collected soils were amended with 13C-labeled traditional substrates (acetate and sodium bicarbonate/ H2) and methylated substrates (methanol, monomethylamine (“MMA”), dimethylsulfide (“DMS”)) and monitored for δ13C-CH4, δ 13C-CO2, and net CH4 and CO2 production in laboratory incubations. The peatlands included in the study were (1) the S1 Bog, home to the SPRUCE Experiment and located at the Marcell Experimental Forest (MEF, U.S. Forest Service), (2) Bog Lake Fen, also located at the MEF, and (3) Zim Bog. These sites have been described in detail previously (Medvedeff et al., 2015)

  16. AmeriFlux CA-SF3 Saskatchewan - Western Boreal, forest burned in 1998.

    DOE Data Explorer

    Amiro, Brian [University of Manitoba; Canadian Forest Service

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site CA-SF3 Saskatchewan - Western Boreal, forest burned in 1998.. Site Description - The 1998 burn site (F98) was in the east part of Prince Albert National Park, Saskatchewan, in the Waskesiu Fire, ignited by lightning that burned about 1700 ha in July 1998. The pre-fire forest consisted of jack pine and black spruce stands, with some intermixed aspen. The fire was severe, consuming much of the top layer of organic soil and killing all trees. In 2001, much of the regenerating vegetation consisted of aspen saplings about 1 m tall and shorter jack pine and black spruce seedlings. An overstory of dead, leafless jack pine trees dominated at a height of 18 m. Sparse grass and herbs, such as fireweed (Epilobium angustifolium L.) covered the ground. There were a large number of fallen dead trees, mostly perched above the ground and not decomposing quickly.

  17. Drought as a modifier of interaction between adult beech and spruce - impacts on tree water use, C budgets and biotic interactions above- and belowground

    NASA Astrophysics Data System (ADS)

    Grams, Thorsten

    2017-04-01

    Understanding biotic interactions among tree species with their microbial associates under drought will be crucial for silviculture in meeting ecological challenges of the future. This contribution gives an overview on a project integrating a throughfall-exclusion experiment (TEE) on adult trees with a natural precipitation gradient (PGR) in central European forests. Focus is on drought affecting species interaction above and belowground, including associated ectomycorrhizal (ECM) communities. Study objects are pure and mixed forests dominated by adult European beech and Norway spruce trees (c. 70-years old). At the throughfall-exclusion experiment (TEE), trees are readily accessible via scaffolding and canopy crane (Kranzberg Forest, southern Germany). Effects of experimentally induced, repeated summer drought are assessed with roughly 100 trees assigned to a total of 12 plots (Kranzberg forest ROOF experiment, kroof.wzw.tum.de). The summer drought treatment started in 2014 and was repeated in 2015 and 2106. The focus on species interaction is intensified by a parallel study along a natural precipitation gradient with plot triplets of monocultures and mixed cultures of European beech and Norway spruce at each of the five study sites. Complementary resource use, effects of competitive vs. facilitation and related changes in ECM communities are exemplified for the two tree species of contrasting foliage (i.e. deciduous vs. evergreen) and stomatal sensitivity to drought (i.e. an-isohydric vs. isohydric behavior). At the TEE site, precipitation throughfall was completely excluded from early spring to late fall (i.e. March to November), resulting in pre-dawn leaf water potentials of both beech and spruce as low as -2.5 MPa. Despite significant reductions in growth and rate of photosynthesis by up to 80% under drought, NSC budget of trees was hardly affected. Moreover, phloem functionality, tested as phloem transport velocity through 13C-labeling of recent photoassimilates, remained unaffected. The link between photosynthesis and stem cellulose (DBH) was assessed based on natural abundance of delta13C and delta18O. Under drought, mixing of recent photoassimilates with older carbohydrates during phloem transport significantly affected isotopic signatures of transported sucrose, diminishing the impact of drought. A quantitative relationship of this mixing effect (i.e. uncoupling of photosynthetic fractionation at the leaf level and isotopic signatures in stem cellulose) was established. Belowground, a distinct decline in fine root biomass, in particular in spruce, was observed. Along that line, repeated summer drought affected species composition of associated ECM fungi in both species. In particular, changes of ECM exploration types (i.e. contact/short-distance vs. long distance) may be related to C shortage of trees. Along the natural precipitation gradient (PGR), basal area increment of tree stems (DBH) was related to 13C discrimination in tree rings. Carbon isotope signatures proved to be a more sensible indicator of tree responses to drought that BAI. Sensitivity of trees was significantly affected by growth conditions, i.e. growth in mono- vs. mixed culture. Higher drought resistance was displayed by spruce on drier sites (i.e. habituation effect) and, conversely, by beech on moist sites, in particular when grown in mixture with spruce.

  18. Interactive effects of wildfire and permafrost on microbial communities and soil processes in an Alaskan black spruce forest.

    Treesearch

    Mark P. Waldrop; Jennifer W. Harden

    2008-01-01

    Boreal forests contain significant quantities of soil carbon that may be oxidized to CO2 given future increases in climate warming and wildfire behavior. At the ecosystem scale, decomposition and heterotrophic respiration are strongly controlled by temperature and moisture, but we questioned whether changes in microbial biomass, activity, or...

  19. Whole-tree clearcutting in New England: manager's guide to impacts on soils, streams, and regeneration

    Treesearch

    Robert S. Pierce; James W. Hornbeck; Wayne C. Martin; Louise M. Tritton; Tattersall C. Smith; Anthony C. Federer; Harry W. Yawney

    1993-01-01

    Studies of impacts of whole-tree clearcutting in spruce-fir, northern hardwood, and central hardwood forest types are summarized for use by practicing foresters, land managers, environmental protection agencies and organizations, and the general public. Guidelines are given for protecting soils, stream water quality, nutrient cycles, and site productivity.

  20. Make way for seedlings: regenerating white spruce in Alaska

    Treesearch

    Rhonda Mazza; Andrew Youngblood

    2012-01-01

    Alaska's boreal forest have experienced unprecedented levels of disturbance. Fire is becoming more frequent and burning larger areas compared to the 1960s and 1970s. In the mid 1990s, insect outbreaks reached epidemic proportions. During the same period, timber harvesting increased to meet demand for logs no longer coming from the Pacific Northwest forest. Alaska...

  1. Geoecology of a forest watershed underlain by serpentine in Central Europe

    Treesearch

    Pavel Krám; Filip Oulehle; Veronika Štedrá; Jakub Hruška; James B. Shanley; Rakesh Minocha; Elena Traister

    2009-01-01

    The geoecology of a serpentinite-dominated site in the Czech Republic was investigated by rock, soil, water, and plant analyses. The 22-ha Pluhuv Bor watershed is almost entirely forested by a nearly 110-year old plantation of Picea abies (Norway Spruce) mixed with native Pinus sylvestris (Scots Pine) in the highest elevations...

  2. The care and handling of the forest gene pool

    Treesearch

    Roy R. Silen; Ivan Doig

    1976-01-01

    What must be the world's most magnificent pool of forest genes has timbered our Pacific slopes.Why else do the tallest firs, pines, spruces, hemlocks, redwoods, and larches all rise along the Pacific Coast of North America? Does their hugeness simply thrust up from our deep soils and mild, rainy climate? From a vantage point of three...

  3. Botanical reconnaissance of Nancy Brook Research Natural Area

    Treesearch

    Joshua L. Royte; Daniel D. Sperduto; John P. Lortie

    1996-01-01

    A survey of the flora and natural communities of Nancy Brook Research Natural Area, Crawford Notch, White Mountain National Forest, New Hampshire, was conducted during the summer and fall of 1992. Nancy Brook Research Natural Area is noted for being the largest virgin mountain spruce forest in New Hampshire, and one of the few remaining large examples in the...

  4. Rating spruce-fir silviculture for wildlife and forestry

    Treesearch

    H.S. Crawford; R.M. Frank

    1985-01-01

    Forest managers face a wide array of potential choices when they consider all of the products derived from woodlands. Many of these products compete with one another to some degree. For instance, hardwood regeneration may be removed in thinnings to favor softwood growth. Forest wildlife-is also influenced by silvicultural practice and the manager must decide whether to...

  5. Test of four stand growth simulators for the northeastern United States

    Treesearch

    Thomas M. Schuler; David A. Marquis; Richard L. Ernst; Brian T. Simpson; Brian T. Simpson

    1993-01-01

    Evaluates SILVAH, FIBER, NE-TWIGS, and OAKSIM, simulators commonly used in the northeastern United States, by comparing predicted stand development with actual stand development records for periods ranging from 15 to 50 years. Results varied with stand parameter, forest type, projection length, and geographic area. Except in the spruce-fir forest type where FIBER...

  6. Can Landscape-scale management influence insect outbreak dynamics? A natural experiment for eastern spruce budworm

    Treesearch

    Brian R. Sturtevant; V. Quinn; L.E. Robert; D. Kneeshaw; P. James; M.-J. Fortin; P. Wolter; P. Townsend; B. Cooke; D. Anderson

    2010-01-01

    The balance of evidence suggests forest insect outbreaks today are more damaging than ever because of changes in forest composition and structure induced by fire suppression and post-harvest proliferation of tree species intolerant to herbivory. We hypothesized that landscape connectivity of acceptable host trees increases defoliator population connectivity, altering...

  7. Comparing modern and presettlement forest dynamics of a subboreal wilderness: Does spruce budworm enhance fire risk?

    Treesearch

    Brian R Sturtevant; Brian R Miranda; Douglas J Shinneman; Eric J Gustafson; Peter T. Wolter

    2012-01-01

    Insect disturbance is often thought to increase fire risk through enhanced fuel loadings, particularly in coniferous forest ecosystems. Yet insect disturbances also affect successional pathways and landscape structure that interact with fire disturbances (and vice-versa) over longer time scales. We applied a landscape succession and disturbance model (LANDIS-II) to...

  8. Drought-driven disturbance history characterizes a southern Rocky Mountain subalpine forest

    Treesearch

    R. Justin DeRose; James N. Long

    2012-01-01

    The view that subalpine forest vegetation dynamics in western North America are "driven" by a particular disturbance type (i.e., fire) has shaped our understanding of their disturbance regimes. In the wake of a recent (1990s) landscape- extent spruce beetle (Dendroctonus rufipennis Kirby) outbreak in the southern Rocky Mountains, we re-examined the temporal...

  9. Proceedings of the 12th Lake States Forest Tree Improvement Conference, August 1975.

    Treesearch

    USDA FS

    1976-01-01

    Presents 20 papers concerning recent research in forest genetics, physiology, and allied fields. Species discussed include cottonwood, white spruce, jack pine, white pine, aspen, and others. Emphasizes the role of tree improvement in increasing wood-fiber production. Includes abstracts from papers presented at the 15th Canadian Tree Improvement Association Meeting...

  10. Experimental soil warming effects on C, N, and major element cycling in a low elevation spruce-fir forest soil

    Treesearch

    Lindsey E. Rustad; Ivan J. Fernandez; Stephanie Arnold

    1996-01-01

    The effect of global warming on north temperate and boreal forest soils has been the subject of much recent debate. These soils serve as major reservoirs for C, N, and other nutrients necessary for forest growth and productivity. Given the uncertainties in estimates of organic matter turnover rates and storage, it is unclear whether these soils will serve as short or...

  11. China Report, Agriculture, Hubei Agricultural Geography

    DTIC Science & Technology

    1984-03-14

    the growing of crops. Numerous farm crops, forest trees and pasture grasses are suited to growth in soil with a pH of between 6 and 8. Plants do...kinds of timber forest trees Fir [Abies fabri], dragon spruce [Picea asperata], China fir, Pinus armandi, birch, oaks, mountain poplar [Populus...half of which are in timber forests . The trees most used in construc- tion are massoon pine, oak, Chinese fir, Pinus armandi, Chinese pine [ Pinus

  12. Impacts of nitrogen and sulfur deposition on the growth of red spruce and sugar maple in the United States

    Treesearch

    Jennifer N. Phelan; Paramita Sinha; George Van Houtven; Marion Deerhake; Randall G. Waite; Anne W. Rea; Ginger M. Tennant

    2012-01-01

    Total nitrogen (N) and sulfur (S) deposition in forest systems can have either positive or negative impacts on tree growth. The growth of many forests in North America is limited by N availability. Therefore, N fertilization is often a key component of forest management, and in areas of N deposition, tree growth may be stimulated. However, N additions can sometimes be...

  13. Impact of endochitinase-transformed white spruce on soil fungal communities under greenhouse conditions.

    PubMed

    Lamarche, Josyanne; Stefani, Franck O P; Séguin, Armand; Hamelin, Richard C

    2011-05-01

    Chitinase genes isolated from plants, bacteria or fungi have been widely used in genetic engineering to enhance the resistance of crops and trees to fungal pathogens. However, there are concerns about the possible effect of chitinase-transformed plants on nontarget fungi. This study aimed at evaluating the impact of endochitinase-transformed white spruce on soil fungal communities. Endochitinase-expressing white spruce and untransformed controls were transplanted in soils from two natural forests and grown for 8 months in a greenhouse. Soil fungal biomass and diversity, estimated through species richness and Shannon and Rao diversity indices, were not different between transgenic and control tree rhizospheres. The fungal phylogenetic community structure was the same in soil samples from control and transgenic white spruces after 8 months. Soil type and presence of seedlings had a much more significant impact on fungal community structure than the insertion and expression of the ech42 transgene within the white spruce genome. The results suggest that the insertion and constitutive expression of the ech42 gene in white spruce did not significantly affect soil fungal biomass, diversity and community structure. © 2011 Her Majesty the Queen in Right of Canada FEMS Microbiology Ecology © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd.

  14. Overstory and Understory CO2 and Energy Fluxes of a Black Spruce Forest in Interior Alaska

    NASA Astrophysics Data System (ADS)

    Ikawa, H.; Nakai, T.; Busey, R.; Kim, Y.; Kobayashi, H.; Nagai, S.; Ueyama, M.; Saito, K.; Suzuki, R.; Hinzman, L. D.

    2014-12-01

    Eddy covariance techniques were used to quantify understory contributions to carbon and energy balances, and to evaluate the environmental responses of the overstory and understory at a black spruce forest in interior Alaska. Net ecosystem productivity (NEP), gross primary productivity (GPP), ecosystem respiration (RE), sensible heat flux (H), and latent heat flux (LE) were estimated for the ecosystem (subscripted by 'eco'), canopy (subscripted by 'cano') and forest floor (subscripted by 'floor') based on canopy gap fraction and footprint analyses for 3 years, 2011 - 2013. Fluxes per unit land surface area of black spruce overstory (subscripted by 'b') and that of understory (subscripted by 'u') were also evaluated their ecophysiological responses to micrometeorological environments. Overall, NEPfloor, GPPfloor, REfloor and LEfloor represented 60 (37, growing season in parenthesis) %, 47 (51) %, 47 (54) %, and 75 (76) % of NEPeco, GPPeco, REeco, and LEeco, respectively with the average canopy gap fraction of 0.52 (± 0.073 SD). The year, 2013 was characterized by high air temperature and vapor pressure deficit (VPD) during the growing season. The high temperature and VPD particularly reduced understory NEP and their growth inferred by low green excessive index (GEI), which was correlated to GPPu more strongly than GPPb. LEu linearly increased with vapor pressure deficit (VPD) whereas LEb was insensitive to VPD. Future warming and drying expected in the boreal forest will increase understory evapotranspiration disproportionately to that of black spruce and likely decrease the production of the current understory community. Acknowledgments This study was supported by the Japan Aerospace Exploration Agency (JAXA) and the JAMSTEC-IARC Collaboration Study, with funding provided by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) to the International Arctic Research Center (IARC). The Polar Geospatial Center, University of Minnesota provided the Quick Bird Image as a support for the NSF grand number 1107524. HI acknowledges J. H. Matthes for helping the footprint algorism, R. Hirata, D. McGuire, and E. Euskirchen for fruitful discussion, and Y. Harazono and H. Nagano for providing parts of meteorological data. We thank N. Bauer for editing.

  15. Assessing the resilience of Norway spruce forests through a model-based reanalysis of thinning trials☆

    PubMed Central

    Seidl, Rupert; Vigl, Friedrich; Rössler, Günter; Neumann, Markus; Rammer, Werner

    2017-01-01

    As a result of a rapidly changing climate the resilience of forests is an increasingly important property for ecosystem management. Recent efforts have improved the theoretical understanding of resilience, yet its operational quantification remains challenging. Furthermore, there is growing awareness that resilience is not only a means to addressing the consequences of climate change but is also affected by it, necessitating a better understanding of the climate sensitivity of resilience. Quantifying current and future resilience is thus an important step towards mainstreaming resilience thinking into ecosystem management. Here, we present a novel approach for quantifying forest resilience from thinning trials, and assess the climate sensitivity of resilience using process-based ecosystem modeling. We reinterpret the wide range of removal intensities and frequencies in thinning trials as an experimental gradient of perturbation, and estimate resilience as the recovery rate after perturbation. Our specific objectives were (i) to determine how resilience varies with stand and site conditions, (ii) to assess the climate sensitivity of resilience across a range of potential future climate scenarios, and (iii) to evaluate the robustness of resilience estimates to different focal indicators and assessment methodologies. We analyzed three long-term thinning trials in Norway spruce (Picea abies (L.) Karst.) forests across an elevation gradient in Austria, evaluating and applying the individual-based process model iLand. The resilience of Norway spruce was highest at the montane site, and decreased at lower elevations. Resilience also decreased with increasing stand age and basal area. The effects of climate change were strongly context-dependent: At the montane site, where precipitation levels were ample even under climate change, warming increased resilience in all scenarios. At lower elevations, however, rising temperatures decreased resilience, particularly at precipitation levels below 750–800 mm. Our results were largely robust to different focal variables and resilience definitions. Based on our findings management can improve the capacity to recover from partial disturbances by avoiding overmature and overstocked conditions. At increasingly water limited sites a strongly decreasing resilience of Norway spruce will require a shift towards tree species better adapted to the expected future conditions. PMID:28860674

  16. Carbon stocks of trees killed by bark beetles and wildfire in the western United States

    USGS Publications Warehouse

    Hicke, Jeffrey A.; Meddens, Arjan J.H.; Allen, Craig D.; Kolden, Crystal A.

    2013-01-01

    Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984-2010, fires killed trees that contained 5-11 Tg C year-1 and during 1997-2010, beetles killed trees that contained 2-24 Tg C year-1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5-10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States.

  17. AmeriFlux CA-SF2 Saskatchewan - Western Boreal, forest burned in 1989.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Amiro, Brian

    This is the AmeriFlux version of the carbon flux data for the site CA-SF2 Saskatchewan - Western Boreal, forest burned in 1989.. Site Description - Amiro_et_al_2006, AFM/136:...The 1989 burn site (F89) was northeast of Prince Albert National Park, Saskatchewan, with the humancaused fire covering 13,500 ha. Parts of the area had been logged prior to the fire, and slash residues would have been burned in some locations. Parts of the area were aerially seeded with jack pine seeds in the winter of 1990. The present tree canopy was composed of balsam poplar (Populus balsamifera L.), jack pine, trembling aspen, andmore » birch (Betula papyrifera Marsh.) and prior to the fire, the stand consisted of these same species aswell asblack spruce.Deadsnags of black spruce and jack pinewere still standing, althoughmost had fallen over and formed a leaningmix of dry, dead tree boles. The understory vegetation consisted mostly of black spruce saplings, saplings of the tree overstory species, bearberry, blueberry (Vaccinium myrtilloides Michx.), raspberry (Rubus idaeus L.), rose (Rosa acicularis Lindl.), bunchberry (Cornus canadensis L.), and reed grass (Calamagrostis canadensis (Michx.) Nutt.).« less

  18. Calcium addition at the Hubbard Brook Experimental Forest increases sugar storage, antioxidant activity and cold tolerance in native red spruce (Picea rubens).

    PubMed

    Halman, Joshua M; Schaberg, Paul G; Hawley, Gary J; Eagar, Christopher

    2008-06-01

    In fall (November 2005) and winter (February 2006), we collected current-year foliage of native red spruce (Picea rubens Sarg.) growing in a reference watershed and in a watershed treated in 1999 with wollastonite (CaSiO(3), a slow-release calcium source) to simulate preindustrial soil calcium concentrations (Ca-addition watershed) at the Hubbard Brook Experimental Forest (Thornton, NH). We analyzed nutrition, soluble sugar concentrations, ascorbate peroxidase (APX) activity and cold tolerance, to evaluate the basis of recent (2003) differences between watersheds in red spruce foliar winter injury. Foliar Ca and total sugar concentrations were significantly higher in trees in the Ca-addition watershed than in trees in the reference watershed during both fall (P=0.037 and 0.035, respectively) and winter (P=0.055 and 0.036, respectively). The Ca-addition treatment significantly increased foliar fructose and glucose concentrations in November (P=0.013 and 0.007, respectively) and foliar sucrose concentrations in winter (P=0.040). Foliar APX activity was similar in trees in both watersheds during fall (P=0.28), but higher in trees in the Ca-addition watershed during winter (P=0.063). Cold tolerance of foliage was significantly greater in trees in the Ca-addition watershed than in trees in the reference watershed (P<0.001). Our results suggest that low foliar sugar concentrations and APX activity, and reduced cold tolerance in trees in the reference watershed contributed to their high vulnerability to winter injury in 2003. Because the reference watershed reflects forest conditions in the region, the consequences of impaired physiological function caused by soil Ca depletion may have widespread implications for forest health.

  19. VAM populations in relation to grass invasion associated with forest decline.

    PubMed

    Vosatka, M; Cudlin, P; Mejstrik, V

    1991-01-01

    Spruce stands in Northern Bohemia forests, damaged to various degrees by industrial pollution, have shown establishment of grass cover following tree defoliation. Populations of vesicular-arbuscular mycorrhizal (VAM) fungi were studied under this grass cover in four permanent plots with spruce under different levels of pollution stress. Soil and root samples were collected in April and June within each plot as follows: (1) sites without grass, (2) sites with initial stages of grass invasion, and (3) sites with fully developed grass cover. In all plots, the highest number of propagules were recovered from samples taken from sites having full grass cover. Mycorrhizal infection of grass was highest in the plot with the severest pollution damage and lowest in the least damaged plot. The development of grass cover and VAM infection of grass increased with tree defoliation caused by air pollution.

  20. Warming delays autumn declines in photosynthetic capacity in a boreal conifer, Norway spruce (Picea abies).

    PubMed

    Stinziano, Joseph R; Hüner, Norman P A; Way, Danielle A

    2015-12-01

    Climate change, via warmer springs and autumns, may lengthen the carbon uptake period of boreal tree species, increasing the potential for carbon sequestration in boreal forests, which could help slow climate change. However, if other seasonal cues such as photoperiod dictate when photosynthetic capacity declines, warmer autumn temperatures may have little effect on when carbon uptake capacity decreases in these species. We investigated whether autumn warming would delay photosynthetic decline in Norway spruce (Picea abies (L.) H. Karst.) by growing seedlings under declining weekly photoperiods and weekly temperatures either at ambient temperature or a warming treatment 4 °C above ambient. Photosynthetic capacity was relatively constant in both treatments when weekly temperatures were >8 °C, but declined rapidly at lower temperatures, leading to a delay in the autumn decline in photosynthetic capacity in the warming treatment. The decline in photosynthetic capacity was not related to changes in leaf nitrogen or chlorophyll concentrations, but was correlated with a decrease in the apparent fraction of leaf nitrogen invested in Rubisco, implicating a shift in nitrogen allocation away from the Calvin cycle at low autumn growing temperatures. Our data suggest that as the climate warms, the period of net carbon uptake will be extended in the autumn for boreal forests dominated by Norway spruce, which could increase total carbon uptake in these forests. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Using LiDAR to evaluate forest landscapes and health factors and their relationship to habitat of the endangered Mount Graham red squirrel on the Coronado National Forest, Pinaleno Mountains, Arizona [Chap. 12

    Treesearch

    John Anhold; Brent Mitchell; Craig Wilcox; Tom Mellin; Melissa Merrick; Ann Lynch; Mike Walterman; Donald Falk; John Koprowski; Denise Laes; Don Evans; Haans. Fisk

    2015-01-01

    The Pinaleno Mountains in southeastern Arizona represent a Madrean sky island ecosystem that contains the southernmost expanse of spruce-fir forest type in North America. This ecosystem is also the last remaining habitat for the Mt. Graham red squirrel (Tamiasciurus hudsonicus grahamenis), a federally listed endangered species. Due to a general shift in...

  2. Environmental Assessment for the Construction of Power and Fiber Optic Lines to Facilities in the Yukon Training Area, Alaska - Phase 4

    DTIC Science & Technology

    2007-11-01

    of dwarf arctic birch and bog rosemary. Understory in most areas includes Labrador tea, lowbush cranberry , and blueberry. Occasionally the black...wild rose, blueberry, and highbush cranberry are common shrubs. Mixed forests usually develop from stands of pure or nearly pure broadleaftrees...forest type include tamarack, blueberry, lowbush cranberry , labrador tea, and feather moss. It is unclear what type of black spruce lowland forest, if

  3. Simulating stand climate, phenology, and photosynthesis of a forest stand with a process-based growth model.

    PubMed

    Rötzer, Thomas; Leuchner, Michael; Nunn, Angela J

    2010-07-01

    In the face of climate change and accompanying risks, forest management in Europe is becoming increasingly important. Model simulations can help to understand the reactions and feedbacks of a changing environment on tree growth. In order to simulate forest growth based on future climate change scenarios, we tested the basic processes underlying the growth model BALANCE, simulating stand climate (air temperature, photosynthetically active radiation (PAR) and precipitation), tree phenology, and photosynthesis. A mixed stand of 53- to 60-year-old Norway spruce (Picea abies) and European beech (Fagus sylvatica) in Southern Germany was used as a reference. The results show that BALANCE is able to realistically simulate air temperature gradients in a forest stand using air temperature measurements above the canopy and PAR regimes at different heights for single trees inside the canopy. Interception as a central variable for water balance of a forest stand was also estimated. Tree phenology, i.e. bud burst and leaf coloring, could be reproduced convincingly. Simulated photosynthesis rates were in accordance with measured values for beech both in the sun and the shade crown. For spruce, however, some discrepancies in the rates were obvious, probably due to changed environmental conditions after bud break. Overall, BALANCE has shown to respond to scenario simulations of a changing environment (e.g., climate change, change of forest stand structure).

  4. Adaptive forest management for drinking water protection under climate change

    NASA Astrophysics Data System (ADS)

    Koeck, R.; Hochbichler, E.

    2012-04-01

    Drinking water resources drawn from forested catchment areas are prominent for providing water supply on our planet. Despite the fact that source waters stemming from forested watersheds have generally lower water quality problems than those stemming from agriculturally used watersheds, it has to be guaranteed that the forest stands meet high standards regarding their water protection functionality. For fulfilling these, forest management concepts have to be applied, which are adaptive regarding the specific forest site conditions and also regarding climate change scenarios. In the past century forest management in the alpine area of Austria was mainly based on the cultivation of Norway spruce, by the way neglecting specific forest site conditions, what caused in many cases highly vulnerable mono-species forest stands. The GIS based forest hydrotope model (FoHyM) provides a framework for forest management, which defines the most crucial parameters in a spatial explicit form. FoHyM stratifies the spacious drinking water protection catchments into forest hydrotopes, being operational units for forest management. The primary information layer of FoHyM is the potential natural forest community, which reflects the specific forest site conditions regarding geology, soil types, elevation above sea level, exposition and inclination adequately and hence defines the specific forest hydrotopes. For each forest hydrotope, the adequate tree species composition and forest stand structure for drinking water protection functionality was deduced, based on the plant-sociological information base provided by FoHyM. The most important overall purpose for the related elaboration of adaptive forest management concepts and measures was the improvement of forest stand stability, which can be seen as the crucial parameter for drinking water protection. Only stable forest stands can protect the fragile soil and humus layers and hence prevent erosion process which could endanger the water resources. Forest stands which are formed by a tree species set which conforms to the potential natural forest community are more stable than the currently wide-spread mono-species Norway spruce plantations, especially in times of climate change, where e.g. bark beetle infestations threat spruce with increased intensity. FoHyM also provides the relevant ecological boundary conditions for any estimation of climate change adaptations. The adaptation of the tree species distribution within each forest hydrotope to climate change conditions was fulfilled by the integration of climate change scenarios and the estimation of the eco-physiological characteristics of related tree species. Hence it was possible to define the tree species distribution related to a specific climate change scenario for each forest hydrotope. The silvicultural concepts and measures to accomplish the defined tree species distribution and forest stand structure for each forest hydrotope were defined and elaborated by taking the specific requirements of drinking water protection areas into account, what e.g. comprised the prohibition of the clear cut technique and the application of continuous cover forest management concepts. The overall purpose of these adaptive silvicultural concepts and techniques which were based on the application of FoHyM was the improvement of the water protection functionality of forest stands within drinking water protection zones.

  5. Heavy metal pollution and forest health in the Ukrainian Carpathians.

    PubMed

    Shparyk, Y S; Parpan, V I

    2004-07-01

    The Ukrainian Carpathians are characterized by high air pollution caused by emissions from numerous industries. We have been monitoring the state of forests in this region since 1989. The highest levels of tree defoliation (>30%) are found close to industrial emission sources and in the upper mountain forests of the Ivano-Frankivsk and Chernivtsi regions. This is caused by a combination of strong anthropogenic influences (pollution, illegal uses, recreation) as well as poor site and climatic conditions. In the Ivano-Frankivsk region, Cd and Mo accumulate in forest soils; Cr, Mo and Zn soil concentrations are higher than their limit levels; and Pb concentrations exceed toxic levels close to industrial areas (10% of the region territory). Local background levels of heavy metals are greatly exceeded in snow close to industrial regions. Analysis of correlation matrices shows that the chemical elements Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, V and Zn occur at pollution levels in natural ecosystems in the Ukrainian Carpathians. Maximum concentrations of toxic elements occur in the oak forest zone; the most industrially developed area of the region. Toxic heavy metals in the Ukrainian Carpathians forests enter with precipitation and dustfall, then become fixed in soil and accumulate in leaves, needles of vascular plants and mosses. Concentrations of these metals decrease with altitude: highest in the oak forests, less in beech, and lowest in the spruce forest zones. However, some chemical elements have the highest concentrations in spruce forests; V in needles, As in snow, and Ba and Al in soils.

  6. Cone and seed yields in white spruce seed production areas

    Treesearch

    John A. Pitcher

    1966-01-01

    The source of seed is an important consideration in the reforestation program on the National Forests in the North Central Region. Thirty-five seed production areas have been set up in the Region, along the lines proposed by the North Central Forest Experiment Station, to provide control of seed source. Red pine, white pine, shortleaf and loblolly pine, and white...

  7. Root-associated ectomycorrhizal fungi shared by various boreal forest seedlings naturally regenerating after a fire in interior Alaska and correlation of different fungi with host growth responses

    Treesearch

    Elizabeth Bent; Preston Kiekel; Rebecca Brenton; D.Lee Taylor

    2011-01-01

    The role of common mycorrhizal networks (CMNs) in postfire boreal forest successional trajectories is unknown. We investigated this issue by sampling a 50-m by 40-m area of naturally regenerating black spruce (Picea mariana), trembling aspen, (Populus tremuloides), and paper birch (Betula papyrifera)...

  8. Species composition influences management outcomes following mountain pine beetle in lodgepole pine-dominated forests

    Treesearch

    Kristen Pelz; C. C. Rhoades; R. M. Hubbard; M. A. Battaglia; F. W. Smith

    2015-01-01

    Mountain pine beetle outbreaks have killed lodgepole pine on more than one million hectares of Colorado and southern Wyoming forest during the last decade and have prompted harvest operations throughout the region. In northern Colorado, lodgepole pine commonly occurs in mixed stands with subalpine fir, Engelmann spruce, and aspen. Variation in tree species composition...

  9. Impacts of cloud immersion on microclimate, photosynthesis and water relations of fraser fir in a temperate mountain cloud forest

    Treesearch

    Keith Reinhardt; William K. Smith

    2010-01-01

    The red spruce-Fraser fir ecosystem (Picea rubens Sarg.-Abies fraseri [Pursh] Poir.) of the southern Appalachian mountains is a temperate zone cloud forest immersed in clouds for 30 to 40 percent of a typical summer day, and experiencing immersion on about 65 percent of all days annually. We compared the microclimate,...

  10. Cloud immersion alters microclimate, photosynthesis and water relations in Rhododendron catawbiense and Abies fraseri seedlings in the southern Appalachian Mountains, USA

    Treesearch

    Daniel M. Johnson; William K. Smith

    2008-01-01

    The high altitude spruce-fir (Abies fraseri (Pursh) Poiret.-Picea rubens Sarg.) forests of the southern Appalachian Mountains, USA, experience frequent cloud immersion. Recent studies indicate that cloud bases may have risen over the past 30 years, resulting in less frequent forest cloud immersion, and that further increases in...

  11. Assessing the volume of wood products used to build and maintain recreational structures on the Tongass National Forest: potential opportunities for Alaska wood products substitution.

    Treesearch

    Randall A. Cantrell

    2004-01-01

    Although the Tongass National Forest (TNF) possesses abundant stands of redcedar (Thuja plicata Donn), yellow-cedar (Chamaecyparis nootkatensis (D. Don) Spach), Sitka spruce (Picea sitchensis (Bong.) Carr.), and western hemlock (Tsuga heterophylla (Raf.) Sarg), most of its buildings, bridges, and trails are constructed from...

  12. Early red spruce regeneration and release studies in the central and southern Appalachians

    Treesearch

    James. Rentch

    2010-01-01

    The aftermath of exploitative harvesting and destruction by fire during the 1920s was first encountered by forest researchers employed by the Appalachian Forest Experiment Station (AEFS) based in Asheville, NC. Two of the more productive researchers were Clarence F. Korstian and Leon S. Minckler, and their studies remain instructive today. This presentation will review...

  13. The gypsy moth in the central hardwoods: research and management needs

    Treesearch

    Robert Lawrence; Susan Burks; Dennis Haugen; Marc Linit

    1997-01-01

    The gypsy moth, Lymantria dispar (L.), is the most serious insect defoliator of trees in the Eastern United States. It is currently established in the area northeast of a line from Michigan to Virginia, and occupies most of the Adirondack and Laurentian Mixed Forest Provinces dominated by northern hardwood, spruce and fir forests. The range of the...

  14. Stand characteristics and Ips typographus (L.) (Col., Curculionidae, Scolytinae) infestation during outbreak in northeastern Poland

    Treesearch

    Jacek Hilszczanski; Wojciech Janiszewski; Jose Negron; A. Steve Munson

    2006-01-01

    The study included field data collected from outbreak areas of Norway spruce beetle Ips typographus L., which were used to identify stand conditions associated with outbreak populations. In 2001-2002 data from 100 infested and 100 uninfested plots were collected from eight Forest Districts of State Forests and three National Parks in northeastern Poland. Among 17...

  15. Tree growth, foliar chemistry, and nitrogen cycling across a nitrogen deposition gradient in southern Appalachian deciduous forests

    Treesearch

    Johnny L. Boggs; Steven G. McNulty; Michael J. Gavazzi; Jennifer Moore Myers

    2005-01-01

    The declining health of high-elevation red spruce (Picea rubens Sarg.) and Fraser fir (Abies fraseri (Pursh) Poir.) in the southern Appalachian region has long been linked to nitrogen (N)deposition. Recently, N deposition has also been proposed as a source of negative health impacts in lower elevation deciduous forests. In 1998 we...

  16. Recent research on the management of hemlock-spruce forests in southeast Alaska for multiple values.

    Treesearch

    Michael H. McClellan

    2005-01-01

    This is a review of research findings from silvicultural studies that addressed information needs identified during the revision of the Tongass National Forest land management plan. A central concern of resource managers is balancing tradeoffs among habitat concerns, wood production, wood-product quality, and operability on the Tongass. This paper provides a historical...

  17. Organic debris in small streams, Prince of Wales Island, Southeast Alaska.

    Treesearch

    Frederick J. Swanson; Mason D. Bryant; George W. Lienkaemper; James R. Sedell

    1984-01-01

    Quantities of coarse and fine organic debris in streams flowing through areas clearcut before 1975 are 3 and 6 times greater than quantities in streams sampled in old-growth stands in Tongass National Forest, central Prince of Wales Island, southeast Alaska. The concentration of debris in streams of clearcut Sitka spruce-western hemlock forests in southeast Alaska,...

  18. Seasonal resource selection of Canada lynx in managed forests of the northern Rocky Mountains

    Treesearch

    John R. Squires; Nicholas J. DeCesare; Jay A. Kolbe; Leonard F. Ruggiero

    2010-01-01

    We investigated seasonal patterns in resource selection of Canada lynx (Lynx canadensis) in the northern Rockies (western MT, USA) from 1998 to 2002 based on backtracking in winter (577 km; 10 M, 7 F) and radiotelemetry (630 locations; 16 M, 11 F) in summer. During winter, lynx preferentially foraged in mature, multilayer forests with Engelmann spruce (Picea...

  19. Early response of ground layer plant communities to wildfire and harvesting disturbance in forested peatland ecosystems in northern Minnesota, USA

    Treesearch

    Erika R. Rowe; Anthony W. D' Amato; Brian J. Palik; John C. Almendinger

    2017-01-01

    A rare, stand-replacing fire in northern Minnesota, USA provided the opportunity to compare the effects of wildfire and timber harvesting in two peatland forest communities, nutrient-poor black spruce (Picea mariana) bogs (BSB) and nutrient-rich tamarack (Larix laricina) swamps (RTS). We found the response between the two...

  20. Woody debris dynamics in Interior West forests and woodlands

    Treesearch

    John D. Shaw; James Long; Raffaella Marzano; Matteo Garbarino

    2012-01-01

    Managers are interested in the dynamics of down woody material because of its role as a fuel component, a feature of wildlife habitat, a carbon pool, and other characteristics. We analyzed nearly 9,000 plots from the Interior West, spanning the range from sparse juniper and mesquite woodland to dense spruce-fir forests, in order to characterize down woody material as...

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