WorldWideScience

Sample records for monterey pine forests

  1. Comparison of Monterey pine stress in urban and natural forests

    Science.gov (United States)

    David J. Nowak; Joe R. McBride

    1991-01-01

    Monterey pine street trees within Carmel, California and its immediate vicinity, as well as forest-grown Monterey pine within adjacent natural stands, were sampled with regard to visual stress characteristics, and various environmental and biological variables. Two stress indices were computed, one hypothesized before data collection was based on relative foliage...

  2. Latent infection by Fusarium circinatum influences susceptibility of monterey pine seedlings to pitch canker

    Science.gov (United States)

    Cassandra L. Swett; Thomas R. Gordon

    2012-01-01

    Pitch canker, caused by Fusarium circinatum, is a serious disease affecting Pinus radiata D. Don (Monterey pine) in nurseries, landscapes, and native forests. A typical symptom of pitch canker is canopy dieback resulting from girdling lesions on terminal branches (Gordon et al. 2001). More extensive dieback can result from...

  3. Accumulation of cesium-137 and strontium-90 in ponderosa pine and monterey pine seedlings

    International Nuclear Information System (INIS)

    Entry, J.A.; Rygiewicz, P.T.; Emmingham, W.H.

    1993-01-01

    Because ponderosa pine Pinus ponderosa and Monterey pone (P. radiata D Don) have exceptionally fast growth rates and their abscised needles are not readily dispersed by wind, these species may be valuable for removing radioisotopes from contaminated soils. Ponderosa and Monterey pine seedlings were tested for their ability to accumulate 137 Cs and 90 Sr-characteristic radioisotopes of nuclear fallout-from contaminated soil. Seedlings were grown for 3 mo in 165 cm 3 sphagnum peat moss/perlite (1:1 V/V) in a growth chamber. In Exp. 1, seedling accumulation of 137 Cs and 90 Sr after 1 mo of exposure was measured. In Exp. 2, seedling accumulation of the radioisotopes during different-length exposures was measured. Seedling accumulation of 137 CS and 90 Sr at different concentrations of the radioisotopes in the growth medium was measured in Exp. 3. Ponderosa pine accumulated 6.3% of the 137 Cs and I.5% of the 90 Sr present in the growth medium after 1 mo; Monterey pine accumulated 8.3% of the 137 Cs and 4.5% of the 90 Sr. Accumulation of 137 Cs and 90 Sr by both coniferous species was curvilinearly related to duration of exposure. Accumulation of 137 Cs and 90 Sr by both species increased with increasing concentration in the growth medium and correlated curvilinearly with radioisotope concentration in the growth medium. Large areas throughout the world are contaminated with 137 Cs and 90 Sr as a result of nuclear weapons testing or atomic reactor accidents. The ability of trees to sequester and store 137 Cs and 90 Sr introduces the possibility of using reforestation to remediate contaminated soils

  4. Cost Benefit Analysis of the Monterey Pines Golf Course

    National Research Council Canada - National Science Library

    Zielinski, Matthew

    2000-01-01

    ..., the government-operated course in the Monterey area. The main purpose of this thesis is to examine the costs and benefits of having a government-operated course in Monterey, where the golf market is extremely competitive, and to examine alternatives...

  5. Effects of pruning in Monterey pine plantations affected by Fusarium circinatum

    Energy Technology Data Exchange (ETDEWEB)

    Bezos, D.; Lomba, J. M.; Martinez-Alvarez, P.; Fernandez, M.; Diez, J. J.

    2012-07-01

    Fusarium circinatum Nirenberg and O'Donnell (1998) is the causal agent of Pitch Canker Disease (PCD) in Pinus species, producing damage to the main trunk and lateral branches as well as causing branch dieback. The disease has been detected recently in northern Spain in Pinus spp. seedlings at nurseries and in Pinus radiata D. Don adult trees in plantations. Fusarium circinatum seems to require a wound to enter the tree, not only that as caused by insects but also that resulting from damage by humans, i.e. mechanical wounds. However, the effects of pruning on the infection process have yet to be studied. The aim of the present study was to know how the presence of mechanical damage caused by pruning affects PCD occurrence and severity in P. radiata plantations. Fifty P. radiata plots (pruned and unpruned) distributed throughout 16 sites affected by F. circinatum in the Cantabria region (northern Spain) were studied. Symptoms of PCD presence, such as dieback, oozing cankers and trunk deformation were evaluated in 25 trees per plot and related to pruning effect. A significant relationship between pruning and the number of cankers per tree was observed, concluding that wounds caused by pruning increase the chance of pathogen infection. Other trunk symptoms, such as the presence of resin outside the cankers, were also higher in pruned plots. These results should be taken into account for future management of Monterey Pine plantations. (Author) 36 refs.

  6. Limber pine forests on the leading edge of white pine blister rust distribution in Northern Colorado

    Science.gov (United States)

    Jennifer G. Klutsch; Betsy A. Goodrich; Anna W. Schoettle

    2011-01-01

    The combined threats of the current mountain pine beetle (Dendroctonus ponderosae, MPB) epidemic with the imminent invasion of white pine blister rust (caused by the non-native fungus Cronartium ribicola, WPBR) in limber pine (Pinus flexilis) forests in northern Colorado threatens the limber pine's regeneration cycle and ecosystem function. Over one million...

  7. Forest development and carbon dynamics after mountain pine beetle outbreaks

    Science.gov (United States)

    E. Matthew. Hansen

    2014-01-01

    Mountain pine beetles periodically infest pine forests in western North America, killing many or most overstory pine stems. The surviving secondary stand structure, along with recruited seedlings, will form the future canopy. Thus, even-aged pine stands become multiaged and multistoried. The species composition of affected stands will depend on the presence of nonpines...

  8. Restoring fire in lodgepole pine forests of the Intermountain west

    Science.gov (United States)

    Colin C. Hardy; Ward W. McCaughey

    1997-01-01

    We are developing new management treatments for regenerating and sustaining lodgepole pine (Pinus contorta) forests through emulation of natural disturbance processes. Lodgepole pine is the principal forest cover on over 26 million hectares in western North America. While infrequent, stand replacing fires following mountain pine beetle outbreaks are common to the...

  9. Historic forests and endemic mountain pine beetle and dwarf mistletoe

    Science.gov (United States)

    Jose Negron

    2012-01-01

    Mountain pine beetle has always been a significant disturbance agent in ponderosa and lodgepole pine forests in Colorado. Most studies have examined the impacts to forest structure associated with epidemic populations of a single disturbance agent. In this paper we address the role of endemic populations of mountain pine and their interactions with dwarf mistletoe...

  10. Nutrient Management in Pine Forests

    Science.gov (United States)

    Allan E. Tiarks

    1999-01-01

    Coastal plain soils are naturally low in fertility and many pine stands will give an economic response to fertilization, especially phosphorus. Maintaining the nutrients that are on the site by limiting displacement of logging slash during and after the harvest can be important in maintaining the productivity of the site and reducing the amount of fertilizer required...

  11. Reverting urban exotic pine forests to Macchia and indigenous ...

    African Journals Online (AJOL)

    Reverting urban exotic pine forests to Macchia and indigenous forest ... Harvesting operations were planned to make the transition from high open ... Key words: Strip-cutting, Cable yarding, Participatory planning, Shelterwood, Urban forests ...

  12. Calculating wind profiles above a pine forest

    International Nuclear Information System (INIS)

    Murphy, C.E.; Dexter, A.H.

    1978-01-01

    A major part of the environmental transport work at the Savannah River Laboratory (SRL) involves the dispersion of airborne pollutants (aerosols and gases). A major part of the Savannah River Plant (SRP) site is covered with pine forests. Because forests are ''rough'' surfaces which increase turbulence and surface shear stress and, hence, alter the dispersion patterns, the nature of the wind profiles above the forests is being investigated. Two methods for determining the surface shear caused by the atmospheric wind field over a pine plantation were compared. Friction velocity [the square root of the ratio of shearing stress over the density of air; U/sub */ = (stress/density)1/2] calculated by eddy correlation was compared with friction velocity calculated from wind profiles. Data from the first five meters above the pine forest were compared. The data indicated that there was no significant difference in the mean friction velocity measured by each method. However, there were large differences in individual values calculated by the two methods for many of the measurement periods. An attempt was made to reconcile the differences in the measured values, but no satisfactory method was found

  13. Longleaf pine forests and woodlands: old growth under fire!

    Science.gov (United States)

    Joan L. Walker

    1999-01-01

    The author discusses a once widespread forest type of the Southeast – longleaf pine dominated forests and woodlands. This system depends on fire – more or less frequent, and often of low intensity. Because human-mediated landscape fragmentation has drastically changed the behavior of fire on longleaf pine dominated landscapes, these forests and woodlands will never be...

  14. Energy balance of a pine forest

    International Nuclear Information System (INIS)

    Murphy, C.E.; Dexter, A.H.

    1978-01-01

    Studies of the energy balance of a pine forest were initiated at the Savannah River Laboratory (SRL) to gain information on the exchange of gaseous materials between the atmosphere and the forest ecosystem. This information allows better estimates of the deposition velocities of gaseous pollutants necessary for plume calculations and ecosystem modeling studies. Studies to date show that the exchange of water vapor is influenced most by diffusion resistances associated with the vegetative canopy. Vegetative and atmospheric diffusion resistance vary diurnally, with high values occurring at night and low values observed during the day. Thus, water vapor exchange is greatest during the daylight hours. Future plans include measurements of exchange of other gases such as carbon dioxide and sulfur dioxide

  15. Resilience of ponderosa and lodgepole pine forests to mountain pine beetle disturbance and limited regeneration

    Science.gov (United States)

    Briggs, Jenny S.; Hawbaker, Todd J.; Vandendriesche, Don

    2015-01-01

    After causing widespread mortality in lodgepole pine forests in North America, the mountain pine beetle (MPB) has recently also affected ponderosa pine, an alternate host species that may have different levels of resilience to this disturbance. We collected field data in ponderosa pine- and lodgepole pine-dominated forests attacked by MPB in Colorado and then simulated stand growth over 200 years using the Forest Vegetation Simulator. We compared scenarios of no disturbance with scenarios of MPB-caused mortality, both with and without regeneration. Results indicated that basal area and tree density recovered to predisturbance levels relatively rapidly (within 1‐8 decades) in both forest types. However, convergence of the disturbed conditions with simulated undisturbed conditions took longer (12‐20+ decades) and was delayed by the absence of regeneration. In MPB-affected ponderosa pine forests without regeneration, basal area did not converge with undisturbed conditions within 200 years, implying lower resilience in this ecosystem. Surface fuels accumulated rapidly in both forest types after MPB-induced mortality, remaining high for 3‐6 decades in simulations. Our results suggest that future patterns of succession, regeneration, fuel loading, climate, and disturbance interactions over long time periods should be considered in management strategies addressing MPB effects in either forest type, but particularly in ponderosa pine.

  16. Radiocesium in a Danish pine forest ecosystem

    International Nuclear Information System (INIS)

    Strandberg, Morten

    1994-01-01

    During the autumn of 1991, a Scots pine forest, Tisvilde Hegn, was investigated with respect to the distribution of radiocesium on compartments in the forest ecosystem. The sandy acidic soil is poor, with a circa 5-cm thick layer of organic soil, and clay content is very low, between 0 and 2%. Cesium from Chernobyl is still totally in the upper 5 cm, while almost half of the fallout cesium has penetrated to depths lower than 5 cm. More than 95% of the total amount of 137 Cs is in the soil compartment. The rest is mainly in the trees (3.4%) and vegetation (0.4%), moss and lichen included. The concentrations of radiocesium are highest in the endshoots of the pine trees, and lowest in the hardwood. There are indications that the Chernobyl cesium is mainly distributed in the parts of the trees that have been formed since 1986. Observed Ratios (OR) were used to characterize the ability of the different components of the forest ecosystem to accumulate radiocesium. OR is defined as the ratio between the content of 137 Cs kg -1 (dry wt.) and the deposition per meter square. In vascular plants, mosses and lichens, OR varied between 0.01 and 0.1 m 2 /kg. In fungi, it varied between 0.05 and 4.5 m 2 /kg, though generally it was between 0.2 and 1 m 2 /kg. OR ( 137 Cs kg -1 /dry wt. of meat x 137 Cs m -2 ) levels in three roe deer samples varied between 0.016 and 0.21 kg -1 /dry wt. With an annual harvest of around 70,000 animals, this might be the most important pathway of this radionuclide to man from semi-natural ecosystems in Denmark

  17. Interacting genes in the pine-fusiform rust forest pathosystem

    Science.gov (United States)

    H.V. Amerson; T.L. Kubisiak; S.A. Garcia; G.C. Kuhlman; C.D. Nelson; S.E. McKeand; T.J. Mullin; B. Li

    2005-01-01

    Fusiform rust (FR) disease of pines, caused by Cronartium quercuum f.sp. fusiforme (Cqf), is the most destructive disease in pine plantations of the southern U. S. The NCSU fusiform rust program, in conjunction with the USDA-Forest Service in Saucier, MS and Athens, GA, has research underway to elucidate some of the genetic interactions in this...

  18. Protecting and restoring longleaf pine forests on the Kisatchie National Forest in Louisiana

    Science.gov (United States)

    James D. Haywood; Michael Elliot-Smith; Finis Harris; Alton Martin

    2000-01-01

    Longleaf pine (Pinus palustris Mill.) forests once constituted a major ecosystem in the Southern United States stretching from southeastern Virginia south to central Florida and west into East Texas. These forests covered a wide range of site conditions, from wet pine flatwoods to dry mountain slopes. Intensive exploitation reduced the extent of old-...

  19. Native ectomycorrhizal fungi of limber and whitebark pine: Necessary for forest sustainability?

    Science.gov (United States)

    Cathy L. Cripps; Robert K. Antibus

    2011-01-01

    Ectomycorrhizal fungi are an important component of northern coniferous forests, including those of Pinus flexilis (limber pine) and P. albicaulis (whitebark pine) which are being decimated by white pine blister rust and mountain pine beetles. Ectomycorrhizal fungi are known to promote seedling establishment, tree health, and may play a role in forest sustainability....

  20. Regeneration of different plant functional types in a Masson pine forest following pine wilt disease.

    Science.gov (United States)

    Hu, Guang; Xu, Xuehong; Wang, Yuling; Lu, Gao; Feeley, Kenneth J; Yu, Mingjian

    2012-01-01

    Pine wilt disease is a severe threat to the native pine forests in East Asia. Understanding the natural regeneration of the forests disturbed by pine wilt disease is thus critical for the conservation of biodiversity in this realm. We studied the dynamics of composition and structure within different plant functional types (PFTs) in Masson pine forests affected by pine wilt disease (PWD). Based on plant traits, all species were assigned to four PFTs: evergreen woody species (PFT1), deciduous woody species (PFT2), herbs (PFT3), and ferns (PFT4). We analyzed the changes in these PFTs during the initial disturbance period and during post-disturbance regeneration. The species richness, abundance and basal area, as well as life-stage structure of the PFTs changed differently after pine wilt disease. The direction of plant community regeneration depended on the differential response of the PFTs. PFT1, which has a higher tolerance to disturbances, became dominant during the post-disturbance regeneration, and a young evergreen-broad-leaved forest developed quickly after PWD. Results also indicated that the impacts of PWD were dampened by the feedbacks between PFTs and the microclimate, in which PFT4 played an important ecological role. In conclusion, we propose management at the functional type level instead of at the population level as a promising approach in ecological restoration and biodiversity conservation.

  1. Probability of infestation and extent of mortality models for mountain pine beetle in lodgepole pine forests in Colorado

    Science.gov (United States)

    Jose F. Negron; Jennifer G. Klutsch

    2017-01-01

    The mountain pine beetle, Dendroctonus ponderosae Hopkins, is a significant agent of tree mortality in lodgepole pine (Pinus contorta Dougl. ex Loud.) forests throughout western North America. A large outbreak of mountain pine beetle caused extensive tree mortality in north-central Colorado beginning in the late 1990s. We use data from a network of plots established in...

  2. Short-wave albedo of a pine forest

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, A.

    1985-06-01

    In this paper nine years of continuous records of the short-wave albedo above a Scotch pine forest in middle Europe were analysed. Special emphasis was given to the dependencies of the albedo on its diurnal variation, its annual variation, the solar altitude, the structure of the stand, the cloud cover, the soil moisture and the spectral reflectance. A long-termed trend of the albedo could not be found, e.g. caused by the stand growth. Finally the annual variation of the albedo of the Scotch pine forest was compared with measurements above different surface types in middle Europe.

  3. Nitrogen cycling following mountain pine beetle disturbance in lodgepole pine forests of Greater Yellowstone

    Science.gov (United States)

    Jacob M. Griffin; Monica G. Turner; Martin Simard

    2011-01-01

    Widespread bark beetle outbreaks are currently affecting multiple conifer forest types throughout western North America, yet many ecosystem-level consequences of this disturbance are poorly understood. We quantified the effect of mountain pine beetle (Dendroctonus ponderosae) outbreak on nitrogen (N) cycling through litter, soil, and vegetation in...

  4. How resilient are southwestern ponderosa pine forests after crown fires?

    OpenAIRE

    Savage, M; Mast, J N

    2005-01-01

    The exclusion of low-severity surface fire from ponderosa pine (Pinus ponderosa P. & C. Lawson) forests of the Southwest has changed ecosystem structure and function such that severe crown fires are increasingly causing extensive stand mortality. This altered fire regime has resulted from the intersection of natural drought cycles with human activities that have suppressed natural fires for over a century. What is the trajectory of forest recovery after such fires? This study explores the reg...

  5. Forest litter stocks in Korean pine-broad-leaved forests of the southern Sikhote Alin

    Directory of Open Access Journals (Sweden)

    A. V. Ivanov

    2015-10-01

    Full Text Available The article presents the data on the forest litter of the Korean pine-broad-leaved forests of the South of Primorsky krai. The focus of the research is plantations dominated by Korean pine; areas of the main tree species with ages of 50, 80, 130 and 200 years were selected. The dynamics of the forest litter stock in the pine and broadleaved forests of different ages according to the measurement results for the season in 2014 is stated. In the studied plantation, the forest litter stock varies between 9.7–20.3 t ha-1. The greatest value of the forest litter stock is recorded in old-growth cedar forest (200 years. Relatively high power and the stock of litter are typical for young Korean pine forest that can explain the lower speed of the litter properties change against the dynamics of taxation indicators of the forest stand. The difference between the amount of the litter in the 200-year-old and remaining pine trees are statistically significant at p = 0.05. The dependence of the litter power on the age is not revealed. The coefficient of the forest litter decomposition ranges from 2.55–10.60 that characterizes the high speed of its rotting. The highest coefficient of the litter decomposition has an old-growing pine forest. The schedule of seasonal humidity fluctuations of the forest litter on the chosen plot is made; with increasing cedar forest age, the volumetric moisture content of the forest litter increases; volumetric moisture content on the plots remain relatively unchanged during the season. The area of the Korean pine forests of Primorsky State Academy of Agriculture is 6835 ha. The amount of carbon stock in the forest litter is 38.7 thousand tons C. in this area, while the system of regional assessment of the forest carbon balance estimates this index as 24.3 tons С. The data obtained can be used to adjust the coefficients of regional assessment of the forest carbon balance for cedar forests of Primorsky krai.

  6. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae outbreak in pine forests.

    Directory of Open Access Journals (Sweden)

    Gregory J Pec

    Full Text Available The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae in lodgepole pine (Pinus contorta forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown.

  7. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae) outbreak in pine forests.

    Science.gov (United States)

    Pec, Gregory J; Karst, Justine; Sywenky, Alexandra N; Cigan, Paul W; Erbilgin, Nadir; Simard, Suzanne W; Cahill, James F

    2015-01-01

    The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown.

  8. Has Virginia pine declined? The use of forest health monitoring and other information in the determination

    Science.gov (United States)

    William G. Burkman; William A. Bechtold

    2000-01-01

    This paper examines the current status of Virginia pine, focusing on Forest Health Monitoring (FHM) results and using Forest Inventory and Analysis (FIA) information to determine if Virginia pine is showing a decline. An examination of crown condition data from live trees in the FHM program from 1991 through 1997 showed that Virginia pine had significantly poorer crown...

  9. Restoring forest structure and process stabilizes forest carbon in wildfire-prone southwestern ponderosa pine forests.

    Science.gov (United States)

    Hurteau, Matthew D; Liang, Shuang; Martin, Katherine L; North, Malcolm P; Koch, George W; Hungate, Bruce A

    2016-03-01

    Changing climate and a legacy of fire-exclusion have increased the probability of high-severity wildfire, leading to an increased risk of forest carbon loss in ponderosa pine forests in the southwestern USA. Efforts to reduce high-severity fire risk through forest thinning and prescribed burning require both the removal and emission of carbon from these forests, and any potential carbon benefits from treatment may depend on the occurrence of wildfire. We sought to determine how forest treatments alter the effects of stochastic wildfire events on the forest carbon balance. We modeled three treatments (control, thin-only, and thin and burn) with and without the occurrence of wildfire. We evaluated how two different probabilities of wildfire occurrence, 1% and 2% per year, might alter the carbon balance of treatments. In the absence of wildfire, we found that thinning and burning treatments initially reduced total ecosystem carbon (TEC) and increased net ecosystem carbon balance (NECB). In the presence of wildfire, the thin and burn treatment TEC surpassed that of the control in year 40 at 2%/yr wildfire probability, and in year 51 at 1%/yr wildfire probability. NECB in the presence of wildfire showed a similar response to the no-wildfire scenarios: both thin-only and thin and burn treatments increased the C sink. Treatments increased TEC by reducing both mean wildfire severity and its variability. While the carbon balance of treatments may differ in more productive forest types, the carbon balance benefits from restoring forest structure and fire in southwestern ponderosa pine forests are clear.

  10. Pines

    Science.gov (United States)

    C. Plomion; D. Chagne; D. Pot; S. Kumar; P.L. Wilcox; R.D. Burdon; D. Prat; D.G. Peterson; J. Paiva; P. Chaumeil; G.G. Vendramin; F. Sebastiani; C.D. Nelson; C.S. Echt; O. Savolainen; T.L. Kubisiak; M.T. Cervera; N. de Maria; M.N. Islam-Faridi

    2007-01-01

    Pinus is the most important genus within the Family Pinaceae and also within the gymnosperms by the number of species (109 species recognized by Farjon 2001) and by its contribution to forest ecosystems. All pine species are evergreen trees or shrubs. They are widely distributed in the northern hemisphere, from tropical areas to northern areas in America and Eurasia....

  11. Understory biomass from southern pine forests as a fuel source

    Energy Technology Data Exchange (ETDEWEB)

    Ku, T.T. [Univ. of Arkansas, Monticello, AR (United States); Baker, J.B. [USDA Forest Service, Monticello, AR (United States)

    1993-12-31

    The energy crisis in the US in the late 1970s led to accelerated research on renewable energy resources. The use of woody biomass, harvested from pine forests in the southern US, as a renewable energy source would not only provide an efficient energy alternative to forest industries, but its use would also reduce understory competition and accelerate growth of overstory crop trees. This study was initiated in the early 1980s to investigate the feasibility and applicability of the use of understory vegetation as a possible energy fuel resource. All woody understory vegetation [<14 cm (<5.5 in) in dbh], on 0.2 ha (0.5 ac) plots that represented a range of stand/site conditions of pine stands located in twelve southern Arkansas counties and two northern Louisiana parishes were characterized, quantified, and harvested. Based on the biomass yield from 720 subplots nested within 40 main plots, the top five dominant species in the understory, based on number and size were: Red maple, red oaks, pines, sweetgum, and winged elm. Some other species occurring, but in smaller proportions, were flowering dogwood, beautyberry, white oaks, black gum, wax myrtle, hickories, persimmon, and ashes. Most of these species are deciduous hardwoods that provide high BTU output upon burning. The average yield of chipped understory biomass was 23.5 T/ha with no difference occurring between summer and winter harvests. A predictive model of understory biomass production was developed using a step-wise multivariate regression analysis. In relation to forest type, high density pine stands produced 53% more understory biomass than high density pine-hardwood stands. The average moisture content of biomass was significantly lower when harvested in winter than when harvested in summer.

  12. Vegetation diversity of the Scots pine stands in different forest sites in the Turawa Forest District

    OpenAIRE

    Stefańska-Krzaczek, Ewa; Pech, Paweł

    2014-01-01

    The utility of phytocenotic indices in the diagnosis and classification of forest sites might be limited because of vegetation degeneration in managed forests. However, even in secondary communities it may be possible to determine indicator species, although these may differ from typical and well known plant indicators. The aim of this work was to assess the vegetation diversity of Scots pine stands in representative forest site types along a moisture and fertility gradient. In total ...

  13. Evolution of a research prototype expert system for endemic populations of mountain pine beetle in lodgepole pine forests

    Science.gov (United States)

    Dale L. Bartos; Kent B. Downing

    1989-01-01

    A knowledge acquisition program was written to aid in obtaining knowledge from the experts concerning endemic populations of mountain pine beetle in lodgepole pine forest. An application expert system is then automatically generated by the knowledge acquisition program that contains the codified base of expert knowledge. Data can then be entered into the expert system...

  14. Soil properties in 35 y old pine and hardwood plantations after conversion from mixed pine-hardwood forest

    Science.gov (United States)

    D. Andrew Scott; Michael G. Messina

    2009-01-01

    Past management practices have changed much of the native mixed pine-hardwood forests on upland alluvial terraces of the western Gulf Coastal Plain to either pine monocultures or hardwood (angiosperm) stands. Changes in dominant tree species can alter soil chemical, biological, and physical properties and processes, thereby changing soil attributes, and ultimately,...

  15. Fire, fuels, and restoration of ponderosa pine-Douglas-fir forests in the Rocky Mountains, USA

    OpenAIRE

    Baker, W. L.; Veblen, T. T.; Sherriff, R. L.

    2007-01-01

    Forest restoration in ponderosa pine and mixed ponderosa pine–Douglas fir forests in the US Rocky Mountains has been highly influenced by a historical model of frequent, low-severity surface fires developed for the ponderosa pine forests of the Southwestern USA. A restoration model, based on this low-severity fire model, focuses on thinning and prescribed burning to restore historical forest structure. However, in the US Rocky Mountains, research on fire history and forest structure, and earl...

  16. Retrieval of pine forest biomass using JPL AIRSAR data

    Science.gov (United States)

    Beaudoin, A.; Letoan, T.; Zagolski, F.; Hsu, C. C.; Han, H. C.; Kong, J. A.

    1992-01-01

    The analysis of Jet Propulsion Laboratory (JPL) Airborne Synthetic Aperture Radar (AIRSAR) data over the Landes forest in South-West France revealed strong correlation between L- and especially P-band sigma degrees and the pine forest biomass. To explain the physical link of radar backscatter to biomass, a polarimetric backscattering model was developed and validated. Then the model was used in a simulation study to predict sigma degree sensitivity to undesired canopy and environmental parameters. Main results concerning the data analysis, modeling, and simulation at P-band are reported.

  17. First report of the white pine blister rust fungus, Cronartium ribicola, infecting Pinus flexilis on Pine Mountain, Humboldt National Forest, Elko County, northeastern Nevada, U.S.A.

    Science.gov (United States)

    Detlev R. Vogler; Patricia E. Maloney; Tom Burt; Jacob W. Snelling

    2017-01-01

    In 2013, while surveying for five-needle white pine cone crops in northeastern Nevada, we observed white pine blister rust, caused by the rust pathogen Cronartium ribicola Fisch., infecting branches and stems of limber pines (Pinus flexilis James) on Pine Mountain (41.76975°N, 115.61622°W), Humboldt National Forest,...

  18. Sensitivity of pine flatwoods hydrology to climate change and forest management in Florida, USA

    Science.gov (United States)

    Jianbiao Lu; Ge Sun; Steven G. McNulty; Nicholas B. Comerford

    2009-01-01

    Pine flatwoods (a mixture of cypress wetlands and managed pine uplands) is an important ecosystem in the southeastern U.S. However, long-term hydrologic impacts of forest management and climate change on this heterogeneous landscape are not well understood. Therefore, this study examined the sensitivity of cypress-pine flatwoods...

  19. Impacts of logging and prescribed burning in longleaf pine forests managed under uneven-aged silviculture

    Science.gov (United States)

    Ferhat Kara; Edward Francis Loewenstein

    2015-01-01

    The longleaf pine (Pinus palustris Mill.) ecosystem has historically been very important in the southeastern United States due to its extensive area and high biodiversity. Successful regeneration of longleaf pine forests requires an adequate number of well distributed seedlings. Thus, mortality of longleaf pine seedlings during logging operations...

  20. Management guide to ecosystem restoration treatments: two-aged lodgepole pine forests of central Montana, USA

    Science.gov (United States)

    Sharon M. Hood; Helen Y. Smith; David K. Wright; Lance S. Glasgow

    2012-01-01

    Lodgepole pine is one of the most widely distributed conifers in North America, with a mixed-severity rather than stand-replacement fire regime throughout much of its range. These lodgepole pine forests are patchy and often two-aged. Fire exclusion can reduce two-aged lodgepole pine heterogeneity. This management guide summarizes the effects of thinning and prescribed...

  1. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon

    Science.gov (United States)

    Michelle C. Agne; David C. Shaw; Travis J. Woolley; Mónica E. Queijeiro-Bolaños; Mai-He. Li

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes....

  2. Evaluating potential fire behavior in lodgepole pine-dominated forests after a mountain pine beetle epidemic in north-central Colorado

    Science.gov (United States)

    Jennifer G. Klutsch; Mike A. Battaglia; Daniel R. West; Sheryl L. Costello; Jose F. Negron

    2011-01-01

    A mountain pine beetle outbreak in Colorado lodgepole pine forests has altered stand and fuel characteristics that affect potential fire behavior. Using the Fire and Fuels Extension to the Forest Vegetation Simulator, potential fire behavior was modeled for uninfested and mountain pine beetle-affected plots 7 years after outbreak initiation and 10 and 80% projected...

  3. Pre-visual detection of stress in pine forests

    Science.gov (United States)

    Olson, C. E., Jr.

    1977-01-01

    Pre-visual, or early, detection of forest stress with particular reference to detection of attacks by pine bark beetles is discussed. Preliminary efforts to obtain early detection of attacks by pine bark beetles, using MSS data from the ERIM M-7 scanner, were not sufficiently successful to demonstrate an operational capability, but indicate that joint processing of the 0.71 to 0.73, 2.00 to 2.60, and 9.3 to 11.7 micrometer bands holds some promise. Ratio processing of transformed data from the 0.45 to 0.52, 1.55 to 2.60, and 4.5 to 5.5 or 9.3 to 11.7 micrometer regions appears even more promising.

  4. Fire effects on Gambel oak in southwestern ponderosa pine-oak forests

    Science.gov (United States)

    Scott R. Abella; Peter Z. Fulé

    2008-01-01

    Gambel oak (Quercus gambelii) is ecologically and aesthetically valuable in southwestern ponderosa pine (Pinus ponderosa) forests. Fire effects on Gambel oak are important because fire may be used in pine-oak forests to manage oak directly or to accomplish other management objectives. We used published literature to: (1) ascertain...

  5. Changes in Gambel oak densities in southwestern ponderosa pine forests since Euro-American settlement

    Science.gov (United States)

    Scott R. Abella; Peter Z. Fulé

    2008-01-01

    Densities of small-diameter ponderosa pine (Pinus ponderosa) trees have increased in southwestern ponderosa pine forests during a period of fire exclusion since Euro-American settlement in the late 1800s. However, less well known are potential changes in Gambel oak (Quercus gambelii) densities during this period in these forests....

  6. Tree mortality in drought-stressed mixed-conifer and ponderosa pine forests, Arizona, USA

    Science.gov (United States)

    Joseph L. Ganey; Scott C. Vojta

    2011-01-01

    We monitored tree mortality in northern Arizona (USA) mixed-conifer and ponderosa pine (Pinus ponderosa Dougl. ex Laws) forests from 1997 to 2007, a period of severe drought in this area. Mortality was pervasive, occurring on 100 and 98% of 53 mixed-conifer and 60 ponderosa pine plots (1-ha each), respectively. Most mortality was attributable to a suite of forest...

  7. Seed release in serotinous lodgepole pine forests after mountain pine beetle outbreak.

    Science.gov (United States)

    Teste, François P; Lieffers, Victor J; Landhausser, Simon M

    2011-01-01

    There are concerns that large-scale stand mortality due to mountain pine beetle (MPB) could greatly reduce natural regeneration of serotinous Rocky Mountain (RM) lodgepole pine (Pinus contorta var. latifolia) because the closed cones are held in place without the fire cue for cone opening. We selected 20 stands (five stands each of live [control], 3 years since MPB [3-yr-MPB], 6 years since MPB [6-yr-MPB], and 9 years since MPB [9-yr-MPB] mortality) in north central British Columbia, Canada. The goal was to determine partial loss of serotiny due to fall of crown-stored cones via breakage of branches and in situ opening of canopy cones throughout the 2008 and 2009 growing seasons. We also quantified seed release by the opening of forest-floor cones, loss of seed from rodent predation, and cone burial. Trees killed by MPB three years earlier dropped approximately 3.5 times more cones via branch breakage compared to live stands. After six years, MPB-killed stands had released 45% of their canopy seed bank through cone opening, cone fall due to breakage, and squirrel predation. Further losses of canopy seed banks are expected with time since we found 9-yr-MPB stands had 38% more open canopy cones. This was countered by the development of a modest forest-floor seed bank (6% of the original canopy seed bank) from burial of cones; this seed bank may be ecologically important if a fire or anthropogenic disturbance reexposes these cones. If adequate levels of regeneration are to occur, disturbances to create seedbeds must occur shortly after tree mortality, before the seed banks are lost. Our findings also suggest that the sustained seed rain (over at least nine years) after MPB outbreak may be beneficial for population growth of ground-foraging vertebrates. Our study adds insight to the seed ecology of serotinous pines under a potentially continental-wide insect outbreak, threatening vast forests adapted to regeneration after fire. Key words: biotic disturbance; cone

  8. The dynamics of pine forests in Prebaikalia under anthropogenic impact

    Directory of Open Access Journals (Sweden)

    T. A. Mikhailova

    2017-02-01

    Full Text Available Analyzed and generalized were the results of prolonged (10–25 years monitoring of condition pine Pinus sylvestris L. forests affected by technogenic pollution and high recreation load in the South Prebaikalia. The results show that both factors have similarity in the stress effect on pine tree-stands, as confirmed by alteration in morphometric parameters of tree assimilating phytomass, decrease in photosynthetic pigments level, as well as by disturbance the nutrient elements proportions in the needles. As tree crown defoliation level reaches 65–70 %, the morphometric parameters for shoots and needles are found to decrease the background level by in 1.3–4.5 times. Under technogenic pollution, the needles’ chlorophylls sum was reduced 2.8–3.5 times, level of carotenoides – to 3.9 times maximum in comparison with the background needles while under high recreation load the green pigments content was reduced 1.9–5.7 times, carotenoids content – to 5.5 times. There is a imbalance in quantitative proportions between nutritional elements under any type of stress, N : P : K proportion changes due to increase of nitrogen level and reduction of phosphorus and potassium level. Index of tree-stand vital condition was calculated on the basis of the representative parameters to analyze the long forest dynamics. Significant reduction was shown in the index in the present time and correspondingly the obvious tendency to pine forest decline in the territories polluted by Irkutsk, Shelekhov, and Angarsk-Usolie industrial centers. At the same time near Cheremkhovo and Sayansk-Zima centers there are not heavy changes in the forest’s condition; during long time a middle level of weakening is registered but in the distance 20 km – a low level of weakening. In the territories characterized by a high recreation load, a sharp trend to declining pine tree-stands vital condition was found, and most clearly it is expressed in the towns of Khuzhir (Olkhon

  9. Simulation of the biomass dynamics of Masson pine forest under different management

    Institute of Scientific and Technical Information of China (English)

    ZHANG Gui-lian; WANG Kai-yun; LIU Xin-wei; PENG Shao-lin

    2006-01-01

    TREE submodel affiliated with TREEDYN was used to simulate biomass dynamics of Masson pine (Pinus massoniana) forest under different managements (including thinning, clear cutting, combining thinning with clear cutting). The purpose was to represent biomass dynamics involved in its development, which can provide scientific arguments for management of Masson pine forest. The results showed the scenario that 10% or 20% of biomass of the previous year was thinned every five years from 15 to 40 years made total biomass of pine forest increase slowly and it took more time to reach a mature community; If clear cutting and thinning were combined, the case C (clear cutting at 20 years of forest age, thinning 50% of remaining biomass at 30 years of forest age, and thinning 50% of remaining biomass again at 40 years of forest age) was the best scenario which can accelerate speed of development of Masson pine forest and gained better economic values.

  10. Assessing the impact of a mountain pine beetle infestation on stand structure of lodgepole pine forests in Colorado using the Forest Inventory and Analysis Annual forest inventory

    Science.gov (United States)

    Michael T. Thompson

    2017-01-01

    The Forest Inventory and Analysis (FIA) annual inventory system began in Colorado in 2002, which coincided with the onset of a major mountain pine beetle (Dendroctonus ponderosae) epidemic. The mortality event, coupled with 11 years of annual inventory data, provided an opportunity to assess the usefulness of the FIA annual inventory system for quantifying the effects...

  11. Forest Modeling of Jack Pine Trees for BOREAS

    Science.gov (United States)

    Moghhadam, Mahta; Saatchi, Sasan

    1994-01-01

    As a part of the intensive field campaign for the Boreal forest ecosystem-atmosphere research (BOREAS) project in August 1993, the NASA/JPL AIRSAR covered an area of about 100 km by 100 km near the Prince Albert National Park in Saskatchewan, Canada. At the same time, ground-truth measurements were made in several stands which have been selected as the primary study sites, as well as in some auxiliary sites. This paper focuses on an area including Jack Pine stands in the Nipawin area near the park.

  12. Southern pine beetle infestations in relation to forest stand conditions, previous thinning, and prescribed burning: evaluation of the Southern Pine Beetle Prevention Program

    Science.gov (United States)

    John T. Nowak; James R. Meeker; David R. Coyle; Chris A. Steiner; Cavell Brownie

    2015-01-01

    Since 2003, the Southern Pine Beetle Prevention Program (SPBPP) (a joint effort of the USDA Forest Service and Southern Group of State Foresters) has encouraged and provided cost-share assistance for silvicultural treatments to reduce stand/forest susceptibility to the southern pine beetle (SPB)(Dendroctonus frontalis Zimmermann) in the southeastern United States....

  13. 75 FR 23666 - Huron-Manistee National Forests, White Pines Wind Farm Project, Mason County, MI

    Science.gov (United States)

    2010-05-04

    ... DEPARTMENT OF AGRICULTURE Forest Service Huron-Manistee National Forests, White Pines Wind Farm Project, Mason County, MI AGENCY: Forest Service, USDA. ACTION: Cancellation Notice of notice of intent to prepare an environmental impact statement. SUMMARY: The Forest Service proposed to prepare an...

  14. Short-term ecological consequences of collaborative restoration treatments in ponderosa pine forests of Colorado

    Science.gov (United States)

    Jennifer S. Briggs; Paula J. Fornwalt; Jonas A. Feinstein

    2017-01-01

    Ecological restoration treatments are being implemented at an increasing rate in ponderosa pine and other dry conifer forests across the western United States, via the USDA Forest Service’s Collaborative Forest Landscape Restoration (CFLR) program. In this program, collaborative stakeholder groups work with National Forests (NFs) to adaptively implement and monitor...

  15. Evaporation from a central Siberian pine forest

    Science.gov (United States)

    Kelliher, F. M.; Lloyd, J.; Arneth, A.; Byers, J. N.; McSeveny, T. M.; Milukova, I.; Grigoriev, S.; Panfyorov, M.; Sogatchev, A.; Varlargin, A.; Ziegler, W.; Bauer, G.; Schulze, E.-D.

    1998-03-01

    Total forest evaporation, E, understorey evaporation, Eu, and environmental variables were measured for 18 consecutive mid-summer days during July 1996 in a 215-year-old stand of Pinus sylvestris L. trees located 40 km southwest of the village of Zotino in central siberia, Russia (61°N, 89°E, 160 m asl). Tree and lichen ( Cladonia and Cladina spp.) understorey one-sided leaf and surface-area indices were 1.5 and 6.0, respectively. Daily E, measured by eddy covariance, was 0.8-2.3 mm day -1 which accounted for 15-67% of the available energy, Ra. Following 12 mm rainfall, daily E reached a maximum on the second day (the first clear day) but declined rapidly thereafter to reach minimum rates within one week. The sandy soil had a range of water content equivalent to only 4 mm water per 100 mm depth of soil. It was estimated that 38% of soil water was utilised before water deficit began to limit E. Eu, also measured by eddy covariance and by lysimeters, was 0.5 to 1.6 mm day -1 or 33-92% of E. Eu was proportional to Ra, but in response to soil drying, the slope of this linear relation declined by a factor of three to a minimum value only three days after the rainfall. Based on the measurements and climatological data, including average annual precipitation of 600 mm year -1 with half as rain during the nominal growing season (1 May to 30 September), water balance calculations suggested E was 265 mm per growing season.

  16. Effects of overstory retention, herbicides, and fertilization on sub-canopy vegetation structure and functional group composition in loblolly pine forests restored to longleaf pine

    Science.gov (United States)

    Benjamin O. Knapp; Joan L. Walker; G. Geoff Wang; Huifeng Hu; Robert N.  Addington

    2014-01-01

    The desirable structure of longleaf pine forests, which generally includes a relatively open canopy of pines, very few woody stems in the mid-story, and a well-developed, herbaceous ground layer, provides critical habitat for flora and fauna and contributes to ecosystem function. Current efforts to restore longleaf pine to upland sites dominated by second-growth...

  17. Forest rodents provide directed dispersal of Jeffrey pine seeds

    Science.gov (United States)

    Briggs, J.S.; Wall, S.B.V.; Jenkins, S.H.

    2009-01-01

    Some species of animals provide directed dispersal of plant seeds by transporting them nonrandomly to microsites where their chances of producing healthy seedlings are enhanced. We investigated whether this mutualistic interaction occurs between granivorous rodents and Jeffrey pine (Pinus jeffreyi) in the eastern Sierra Nevada by comparing the effectiveness of random abiotic seed dispersal with the dispersal performed by four species of rodents: deer mice (Peromyscus maniculatus), yellow-pine and long-eared chipmunks (Tamias amoenus and T. quadrimaculatus), and golden-mantled ground squirrels (Spermophilus lateralis). We conducted two caching studies using radio-labeled seeds, the first with individual animals in field enclosures and the second with a community of rodents in open forest. We used artificial caches to compare the fates of seeds placed at the range of microsites and depths used by animals with the fates of seeds dispersed abiotically. Finally, we examined the distribution and survival of naturally establishing seedlings over an eight-year period.Several lines of evidence suggested that this community of rodents provided directed dispersal. Animals preferred to cache seeds in microsites that were favorable for emergence or survival of seedlings and avoided caching in microsites in which seedlings fared worst. Seeds buried at depths typical of animal caches (5–25 mm) produced at least five times more seedlings than did seeds on the forest floor. The four species of rodents differed in the quality of dispersal they provided. Small, shallow caches made by deer mice most resembled seeds dispersed by abiotic processes, whereas many of the large caches made by ground squirrels were buried too deeply for successful emergence of seedlings. Chipmunks made the greatest number of caches within the range of depths and microsites favorable for establishment of pine seedlings. Directed dispersal is an important element of the population dynamics of Jeffrey pine, a

  18. Comparison of Organic Matter Dynamics in Soil between Japanese Cedar (Cryptomeria japonica) Forest and Adjacent Japanese Red Pine (Pinus densiflora) Forest Established on Flatland

    OpenAIRE

    Terumasa, Takahashi; Akiko, Minami; Yoshito, Asano; Tatsuaki, Kobayashi; Faculty of Horticulture, Chiba Universit; Faculty of Horticulture, Chiba University:(Present)Hashikami town office; Faculty of Horticulture, Chiba University; Faculty of Horticulture, Chiba University

    1999-01-01

    In order to clarify the effects of tree species on organic matter dynamics in soil, we investigated the amount of forest floor material, leaf litter decomposition rate, soil chemical characteristics, soil respiration rate and cellulose decomposition rate in a Japanese cedar forest (cedar plot) and an adjacent Japanese red pine forest (pine plot) established on a flatland. The amount of forest floor material in the cedar plot was 34.5 Mg ha^ which was greater than that in the pine plot. Becaus...

  19. The assessment of environmentally sensitive forest road construction in Calabrian pine forest areas of Turkey.

    Science.gov (United States)

    Tunay, Metin

    2006-07-01

    Forest road construction by bulldozers in Calabrian Pine (Pinus brutia Ten.) forests on mountainous terrain of Turkey causes considerable damage to the environment and the forest standing alongside the road. This situation obliges a study of environmentally sound road construction in Turkey. This study was carried out in 4 sample sites of Antalya Forest Directorate in steep (34-50% gradient) and very steep terrain (51-70% gradient) conditions with bulldozer and excavator machine and direct damages to forest during road construction was determined, including forest area losses and damages to downhill trees in mountainous areas. It was determined that in steep terrain when excavators were used, less forest area (22.16%) was destroyed compared to bulldozers and 26.54% less area in very steep terrain. The proportion of damage on trees where bulldozer worked was nearly twofold higher than excavator was used. The results of this research show that the environmentally sensitive techniques applied for the road construction projects are considerably superior to the traditional use of bulldozers on steep slopes. The environmentally sound forest road construction by use of excavator must be considered an appropriate and reliable solution for mountainous terrain where areas of sensitive forest ecosystems are to be opened up.

  20. Timber, Browse, and Herbage on Selected Loblolly-Shortleaf Pine-Hardwood Forest Stands

    Science.gov (United States)

    Gale L. Wolters; Alton Martin; Warren P. Clary

    1977-01-01

    A thorough vegetation inventory was made on loblolly-shortleaf pine-hardwood stands scheduled by forest industry for clearcutting, site preparation, and planting to pine in north central Louisiana and southern Arkansas. Overstory timber, on the average, contained about equal proportions of softwood and hardwood basal area. Browse plants ranged from 5,500 to over 70,...

  1. Effects of salvage logging on fire risks after bark beetle outbreaks in Colorado lodgepole pine forests

    Science.gov (United States)

    Bryon J. Collins; Chuck C. Rhoades; Michael A. Battaglia; Robert M. Hubbard

    2012-01-01

    Most mature lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) forests in the central and southern Rocky Mountains originated after stand-replacing wildfires or logging (Brown 1975, Lotan and Perry 1983, Romme 1982). In recent years, mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks have created a widespread, synchronous disturbance (i.e.,...

  2. Western dwarf mistletoe infects understory Jeffrey pine seedlings on Cleveland National Forest, California

    Science.gov (United States)

    Robert F. Scharpf; Detlev Vogler

    1986-01-01

    Many young, understory Jeffrey pines (Pinus jeffreyi Grev. & Balf.) were found to be infected by western dwarf mistletoe (Arceuthobium campylopodum Engelm.) on Laguna Mountain, Cleveland National Forest, in southern California. Under heavily infected overstory, about three-fourths of the young pines (about 15 years old on the...

  3. Longleaf pine site response to repeated fertilization and forest floor removal by raking and prescribed burning

    Science.gov (United States)

    Kim Ludovici; Robert Eaton; Stanley Zarnoch

    2018-01-01

    Removal of forest floor litter by pine needle raking and prescribed burning is a common practice in longleaf pine (Pinus palustris Mill.) stands on Coastal Plain sites in the Southeastern United States. Repeated removal of litter by raking and the loss of surface organic matter from controlled burns can affect the...

  4. An Old-Growth Definition for Dry and Dry-Mesic Oak-Pine Forests.

    Science.gov (United States)

    David L. White; F. Thomas. Lloyd

    1998-01-01

    Dry and dry-mesic oak-pine forests are widely distributed from New Jersey to Texas, but representative old-growth stands are rare. Historical accounts of composition, along with information from existing old-growth stands, were used to characterize this type. Shortleaf pine and white oak were the most widely distributed trees across all old-growth stands. Shortleaf was...

  5. Pest Fact Sheet 2007: Southern Pine Beetle prevention initiative: Working for healthier forests

    Science.gov (United States)

    R-8 and Southern Research Station U.S. Department of Agriculture Forest Service Forest Health Protection

    2007-01-01

    From 1999 to 2003, southern pine beetle (SPB) caused unprecedented damage to pine forests in southern Appalachian mountains. These losses severely impacted the natural resource base that supports the South's tourism and wood-based manufacturing industries and also destroyed the habitat of threatened and endangered species, such as the red-cockaded woodpecker....

  6. Eighty-eight years of change in a managed ponderosa pine forest

    Science.gov (United States)

    Helen Y. Smith; Stephen F. Arno

    1999-01-01

    This publication gives an overview of structural and other ecological changes associated with forest management and fire suppression since the early 1900's in a ponderosa pine forest, the most widespread forest type in the Western United States. Three sources of information are presented: (1) changes seen in a series of repeat photographs taken between 1909 and...

  7. Water balance of pine forests: Synthesis of new and published results

    Science.gov (United States)

    Pantana Tor-ngern; Ram Oren; Sari Palmroth; Kimberly Novick; Andrew Oishi; Sune Linder; Mikaell Ottosson-Lofvenius; Torgny Nasholm

    2018-01-01

    The forest hydrologic cycle is expected to have important feedback responses to climate change, impacting processes ranging from local water supply and primary productivity to global water and energy cycles. Here, we analyzed water budgets of pine forests worldwide. We first estimated local water balance of forests dominated by two wide-ranging species: Pinus...

  8. 76 FR 48120 - Black Hills National Forest, Custer, SD-Mountain Pine Beetle Response Project

    Science.gov (United States)

    2011-08-08

    ... species on lands of all ownerships in the Black Hills is ponderosa pine (Pinus ponderosae). Since 1997 the... rated as having high wildfire hazard. Since 1980, due to several factors including drought the Forest...

  9. 77 FR 10717 - Black Hills National Forest, Custer, South Dakota-Mountain Pine Beetle Response Project

    Science.gov (United States)

    2012-02-23

    .... The predominant tree species on lands of all ownerships in the Black Hills is ponderosa pine (Pinus... drought the Forest has seen a dramatic increase in acreage burned by wildfires. In that period over 250...

  10. Latent resilience in ponderosa pine forest: effects of resumed frequent fire.

    Science.gov (United States)

    Larson, Andrew J; Belote, R Travis; Cansler, C Alina; Parks, Sean A; Dietz, Matthew S

    2013-09-01

    Ecological systems often exhibit resilient states that are maintained through negative feedbacks. In ponderosa pine forests, fire historically represented the negative feedback mechanism that maintained ecosystem resilience; fire exclusion reduced that resilience, predisposing the transition to an alternative ecosystem state upon reintroduction of fire. We evaluated the effects of reintroduced frequent wildfire in unlogged, fire-excluded, ponderosa pine forest in the Bob Marshall Wilderness, Montana, USA. Initial reintroduction of fire in 2003 reduced tree density and consumed surface fuels, but also stimulated establishment of a dense cohort of lodgepole pine, maintaining a trajectory toward an alternative state. Resumption of a frequent fire regime by a second fire in 2011 restored a low-density forest dominated by large-diameter ponderosa pine by eliminating many regenerating lodgepole pines and by continuing to remove surface fuels and small-diameter lodgepole pine and Douglas-fir that established during the fire suppression era. Our data demonstrate that some unlogged, fire-excluded, ponderosa pine forests possess latent resilience to reintroduced fire. A passive model of simply allowing lightning-ignited fires to burn appears to be a viable approach to restoration of such forests.

  11. Felling-system and regeneration of pine forests on ecological-genetic-geographical basis

    Directory of Open Access Journals (Sweden)

    S. N. Sannikov

    2015-12-01

    Full Text Available A conception of the adaptation of Scots pine populations to the natural regeneration on open sites with the mosaic retained stand and mineralized soil surface on the basis of the ecological-genetic-geographical investigations in the forests of the Russia and the theory of petropsammofitness-pyrofitness (Sannikov S. N., 1983 has been substantiated. The methods of clear cuts with the seeding from surrounding forest, seed curtains and sufficiently extent of the substrate preparation for the pine selfsown have been selected and elaborated as a main organization principle of the system «felling-regeneration» in the plains pine forests of the forest zone. High regeneration efficiency of this system with the application of original aggregate for the optimal mineralization of the soil substrate (with its synchronous loosing has been shown on the example of dominating pine forest types in the subzone for-forest-steppe of the Western Siberia. The silvicultural-ecological and reproductive-genetic advantages of retaining seed curtains instead of separate seed trees have been substantiated. The basic parameters of the system «felling-regeneration», which guarantee a sufficient success of the following pine regeneration in the for-forest-steppe subzone, have been determined with the help of the methods of the mathematical imitation modeling of the pine selfsown density depending on the area and localization of seed curtains, surrounding forest and the extent of the substrate mineralization. The zonal differentiated system of the fellings and measures for the regeneration optimization in the climatically substituting pine forest types in the Western Siberia has been elaborated according to the parameters, studied earlier, on the ecological-genetic-geographical basis. The principles of this system in forest zone come to the clear strip-fellings with insemination of cuts from the seed curtains and forest walls, and to the hollow-fellings with the

  12. An interdisciplinary, outcome-based approach to astmospheric CO2 mitigation with planted southern pine forests

    Science.gov (United States)

    Martin, T.; Fox, T.; Peter, G.; Monroe, M.

    2012-12-01

    The Pine Integrated Network: Education, Mitigation and Adaptation Project ("PINEMAP") was funded by National Institute of Food and Agriculture to produce outcomes of enhanced climate change mitigation and adaptation in planted southern pine ecosystems. The PINEMAP project leverages a strong group of existing networks to produce synergy and cooperation on applied forestry research in the region. Over the last 50 years, cooperative research on planted southern pine management among southeastern U.S. universities, government agencies, and corporate forest landowners has developed and facilitated the widespread implementation of improved genetic and silvicultural technology. The impact of these regional research cooperatives is difficult to overstate, with current members managing 55% of the privately owned planted pine forestland, and producing 95% of the pine seedlings planted each year. The PINEMAP team includes the eight major forestry cooperative research programs, scientists from eleven land grant institutions, the US Forest Service, and climate modeling and adaptation specialists associated with the multi-state SE Climate Consortium and state climate offices. Our goal is to create and disseminate the knowledge that enables landowners to: harness planted pine forest productivity to mitigate atmospheric CO2; more efficiently use nitrogen and other fertilizer inputs; and adapt their forest management to increase resilience in the face of changing climate. We integrate our team's infrastructure and expertise to: 1) develop breeding, genetic deployment and innovative management systems to increase C sequestration and resilience to changing climate of planted southern pine forests ; 2) understand interactive effects of policy, biology, and climate change on sustainable management; 3) transfer new management and genetic technologies to private industrial and non-industrial landowners; and 4) educate a diverse cross-section of the public about the relevance of forests

  13. Resistance to wildfire and early regeneration in natural broadleaved forest and pine plantation

    Science.gov (United States)

    Proença, Vânia; Pereira, Henrique M.; Vicente, Luís

    2010-11-01

    The response of an ecosystem to disturbance reflects its stability, which is determined by two components: resistance and resilience. We addressed both components in a study of early post-fire response of natural broadleaved forest ( Quercus robur, Ilex aquifolium) and pine plantation ( Pinus pinaster, Pinus sylvestris) to a wildfire that burned over 6000 ha in NW Portugal. Fire resistance was assessed from fire severity, tree mortality and sapling persistence. Understory fire resistance was similar between forests: fire severity at the surface level was moderate to low, and sapling persistence was low. At the canopy level, fire severity was generally low in broadleaved forest but heterogeneous in pine forest, and mean tree mortality was significantly higher in pine forest. Forest resilience was assessed by the comparison of the understory composition, species diversity and seedling abundance in unburned and burned plots in each forest type. Unburned broadleaved communities were dominated by perennial herbs (e.g., Arrhenatherum elatius) and woody species (e.g., Hedera hibernica, Erica arborea), all able to regenerate vegetatively. Unburned pine communities presented a higher abundance of shrubs, and most dominant species relied on post-fire seeding, with some species also being able to regenerate vegetatively (e.g., Ulex minor, Daboecia cantabrica). There were no differences in diversity measures in broadleaved forest, but burned communities in pine forest shared less species and were less rich and diverse than unburned communities. Seedling abundance was similar in burned and unburned plots in both forests. The slower reestablishment of understory pine communities is probably explained by the slower recovery rate of dominant species. These findings are ecologically relevant: the higher resistance and resilience of native broadleaved forest implies a higher stability in the maintenance of forest processes and the delivery of ecosystem services.

  14. Involvement of allelopathy in inhibition of understory growth in red pine forests.

    Science.gov (United States)

    Kato-Noguchi, Hisashi; Kimura, Fukiko; Ohno, Osamu; Suenaga, Kiyotake

    2017-11-01

    Japanese red pine (Pinus densiflora Sieb. et Zucc.) forests are characterized by sparse understory vegetation although sunlight intensity on the forest floor is sufficient for undergrowth. The possible involvement of pine allelopathy in the establishment of the sparse understory vegetation was investigated. The soil of the red pine forest floor had growth inhibitory activity on six test plant species including Lolium multiflorum, which was observed at the edge of the forest but not in the forest. Two growth inhibitory substances were isolated from the soil and characterized to be 15-hydroxy-7-oxodehydroabietate and 7-oxodehydroabietic acid. Those compounds are probably formed by degradation process of resin acids. Resin acids are produced by pine and delivered into the soil under the pine trees through balsam and defoliation. Threshold concentrations of 15-hydroxy-7-oxodehydroabietate and 7-oxodehydroabietic acid for the growth inhibition of L. multiflorum were 30 and 10μM, respectively. The concentrations of 15-hydroxy-7-oxodehydroabietate and 7-oxodehydroabietic acid in the soil were 312 and 397μM, respectively, which are sufficient concentrations to cause the growth inhibition because of the threshold. These results suggest that those compounds are able to work as allelopathic agents and may prevent from the invasion of herbaceous plants into the forests by inhibiting their growth. Therefore, allelopathy of red pine may be involved in the formation of the sparse understory vegetation. Copyright © 2017 Elsevier GmbH. All rights reserved.

  15. Simulating historical disturbance regimes and stand structures in old-forest ponderosa pine/Douglas-fir forests

    Science.gov (United States)

    Mike Hillis; Vick Applegate; Steve Slaughter; Michael G. Harrington; Helen Smith

    2001-01-01

    Forest Service land managers, with the collaborative assistance from research, applied a disturbance based restoration strategy to rehabilitate a greatly-altered, high risk Northern Rocky Mountain old-forest ponderosa pine-Douglas-fir stand. Age-class structure and fire history for the site have been documented in two research papers (Arno and others 1995, 1997)....

  16. The lodgepole × jack pine hybrid zone in Alberta, Canada: a stepping stone for the mountain pine beetle on its journey East across the boreal forest?

    Science.gov (United States)

    Lusebrink, Inka; Erbilgin, Nadir; Evenden, Maya L

    2013-09-01

    Historical data show that outbreaks of the tree killing mountain pine beetle are often preceded by periods of drought. Global climate change impacts drought frequency and severity and is implicated in the range expansion of the mountain pine beetle into formerly unsuitable habitats. Its expanded range has recently reached the lodgepole × jack pine hybrid zone in central Alberta, Canada, which could act as a transition from its historical lodgepole pine host to a jack pine host present in the boreal forest. This field study tested the effects of water limitation on chemical defenses of mature trees against mountain pine beetle-associated microorganisms and on beetle brood success in lodgepole × jack pine hybrid trees. Tree chemical defenses as measured by monoterpene emission from tree boles and monoterpene concentration in needles were greater in trees that experienced water deficit compared to well-watered trees. Myrcene was identified as specific defensive compound, since it significantly increased upon inoculation with dead mountain pine beetles. Beetles reared in bolts from trees that experienced water deficit emerged with a higher fat content, demonstrating for the first time experimentally that drought conditions benefit mountain pine beetles. Further, our study demonstrated that volatile chemical emission from tree boles and phloem chemistry place the hybrid tree chemotype in-between lodgepole pine and jack pine, which might facilitate the host shift from lodgepole pine to jack pine.

  17. Vegetation ecology of eastern white pine and red pine forests in Ontario. Forest fragmentation and biodiversity project technical report No. 11

    Energy Technology Data Exchange (ETDEWEB)

    Carleton, T.J.

    1993-12-31

    This study explored changes in understory species composition and floristic diversity in eastern white pine and red pine stands in Ontario in relation to differences in site condition and stand age. It surveyed 170 natural, fire-origin stands containing at least a 10% component of red pine and white pine basal area throughout the Canadian Shield in Ontario during 1991 and 1992. The stands had not been previously logged and ranged in age from 50-300 years. Sampling was conducted using plots of fixed area. Within these plots, subplots were sampled to capture the variety of vegetation that occurred at different scales. Stand-level data were also recorded outside the fixed area plots. Detailed site data were also collected, including information on soils, topography, coarse woody debris (both standing and fallen), and the nature of the forest floor substrates.

  18. Severity of a mountain pine beetle outbreak across a range of stand conditions in Fraser Experimental Forest, Colorado, United States

    Science.gov (United States)

    Anthony G. Vorster; Paul H. Evangelista; Thomas J. Stohlgren; Sunil Kumar; Charles C. Rhoades; Robert M. Hubbard; Antony S. Cheng; Kelly Elder

    2017-01-01

    The recent mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks had unprecedented effects on lodgepole pine (Pinus contorta var. latifolia) in western North America. We used data from 165 forest inventory plots to analyze stand conditions that regulate lodgepole pine mortality across a wide range of stand structure and species composition at the Fraser...

  19. The status of whitebark pine along the Pacific Crest National Scenic Trail on the Umpqua National Forest.

    Science.gov (United States)

    Ellen Michaels Goheen; Donald J. Goheen; Katy Marshall; Robert S. Danchok; John A. Petrick; Diane E. White

    2002-01-01

    Because of concern over widespread population declines, the distribution, stand conditions, and health of whitebark pine (Pinus albicaulis Englem.) were evaluated along the Pacific Crest National Scenic Trail on the Umpqua National Forest. Whitebark pine occurred on 76 percent of the survey transects. In general, whitebark pine was found in stands...

  20. Strategies, tools, and challenges for sustaining and restoring high elevation five-needle white pine forests in western North America

    Science.gov (United States)

    Robert E. Keane; Anna W. Schoettle

    2011-01-01

    Many ecologically important, five-needle white pine forests that historically dominated the high elevation landscapes of western North America are now being heavily impacted by mountain pine beetle (Dendroctonus spp.) outbreaks, the exotic disease white pine blister rust (WPBR), and altered high elevation fire regimes. Management intervention using specially designed...

  1. Understory vegetation response to mechanical mastication and other fuels treatments in a ponderosa pine forest

    Science.gov (United States)

    Jeffrey M. Kane; J. Morgan Varner; Eric E. Knapp

    2010-01-01

    Questions: What influence does mechanical mastication and other fuel treatments have on: (1) canopy and forest floor response variables that influence understory plant development; (2) initial understory vegetation cover, diversity, and composition; and (3) shrub and non-native species density in a secondgrowth ponderosa pine forest....

  2. Simulation of Landscape Pattern of Old Growth Forests of Korean Pine by Block Kringing

    Science.gov (United States)

    Wang Zhengquan; Wang Qingcheng; Zhang Yandong

    1997-01-01

    The study area was located in Liangshui Natural Reserve. Xaozing'an Mountains, Northeastern China. Korean pine forests are the typical forest ecosystems and landscapes in this region. It is a high degress of spatial and temporal heterogeneity at different scales, which effected on landscape pattern and processes. In this paper we used the data of 144 plots and...

  3. Ecosystem carbon density and allocation across a chronosequence of longleaf pine forests

    Science.gov (United States)

    Lisa J. Samuelson; Thomas A. Stokes; John R. Butnor; Kurt H. Johnsen; Carlos A. Gonzalez-Benecke; Timothy A. Martin; Wendell P. Cropper; Pete H. Anderson; Michael R. Ramirez; John C. Lewis

    2017-01-01

    Forests can partially offset greenhouse gas emissions and contribute to climate change mitigation, mainly through increases in live biomass. We quantified carbon (C) density in 20 managed longleaf pine (Pinus palustris Mill.) forests ranging in age from 5...

  4. Use of Hardwood Tree Species by Birds Nesting in Ponderosa Pine Forests

    Science.gov (United States)

    Kathryn L. Purcell; Douglas A. Drynan

    2008-01-01

    We examined the use of hardwood tree species for nesting by bird species breeding in ponderosa pine (Pinus ponderosa) forests in the Sierra National Forest, California. From 1995 through 2002, we located 668 nests of 36 bird species nesting in trees and snags on four 60-ha study sites. Two-thirds of all species nesting in trees or snags used...

  5. Algological and Mycological Characterization of Soils under Pine and Birch Forests in the Pasvik Reserve

    Science.gov (United States)

    Korneikova, M. V.; Redkina, V. V.; Shalygina, R. R.

    2018-02-01

    The structure of algological and mycological complexes in Al-Fe-humus podzols (Albic Podzols) under pine and birch forests of the Pasvik Reserve is characterized. The number of micromycetes is higher in more acid soils of the pine forest, while the species diversity is greater under the birch forest. The genus Penicillium includes the largest number of species. The greatest abundance and occurrence frequency are typical for Penicillium spinulosum, P. glabrum, and Trichoderma viride in pine forest and for Umbelopsis isabellina, Mucor sp., Mortierella alpina, P. glabrum, Aspergillus ustus, Trichoderma viride, and T. koningii in birch forest. Cyanobacteria-algal cenoses of the investigated soils are predominated by green algae. Soils under birch forest are distinguished by a greater diversity of algal groups due to the presence of diatoms and xanthophytes. Species of frequent occurrence are represented by Pseudococcomyxa simplex and Parietochloris alveolaris in soils of the pine forest and by Tetracystis cf. aplanospora, Halochlorella rubescens, Pseudococcomyxa simplex, Fottea stichococcoides, Klebsormidium flaccidum, Hantzschia amphioxys, Microcoleus vaginatus, and Aphanocapsa sp. in soils under birch forest

  6. Coarse woody debris assay in northern Arizona mixed-conifer and ponderosa pine forests

    Science.gov (United States)

    Joseph L. Ganey; Scott C. Vojta

    2010-01-01

    Coarse woody debris (CWD) provides important ecosystem services in forests and affects fire behavior, yet information on amounts and types of CWD typically is limited. To provide such information, we sampled logs and stumps in mixed-conifer and ponderosa pine (Pinus ponderosa) forests in north-central Arizona. Spatial variability was prominent for all CWD parameters....

  7. Tree canopy types constrain plant distributions in ponderosa pine-Gambel oak forests, northern Arizona

    Science.gov (United States)

    Scott R. Abella

    2009-01-01

    Trees in many forests affect the soils and plants below their canopies. In current high-density southwestern ponderosa pine (Pinus ponderosa) forests, managers have opportunities to enhance multiple ecosystem values by manipulating tree density, distribution, and canopy cover through tree thinning. I performed a study in northern Arizona ponderosa...

  8. Insect Pollinators of Three Rare Plants in a Florida Longleaf Pine Forest

    Science.gov (United States)

    Theresa Pitts-Singer; James L. Hanula; Joan L. Walker

    2002-01-01

    As a result of human activity, longleaf pine (Pinus palustris Miller) forests in the southern United States have been lost or drastically altered. Many of the plant species that historically occupied those forests now persist only as remnants and are classified as threatened or endangered. In order to safeguard such species, a better understanding of...

  9. Capturing forest dependency in the central Himalayan region: Variations between Oak (Quercus spp.) and Pine (Pinus spp.) dominated forest landscapes.

    Science.gov (United States)

    Chakraborty, Anusheema; Joshi, Pawan Kumar; Sachdeva, Kamna

    2018-05-01

    Our study explores the nexus between forests and local communities through participatory assessments and household surveys in the central Himalayan region. Forest dependency was compared among villages surrounded by oak-dominated forests (n = 8) and pine-dominated forests (n = 9). Both quantitative and qualitative analyses indicate variations in the degree of dependency based on proximity to nearest forest type. Households near oak-dominated forests were more dependent on forests (83.8%) compared to households near pine-dominated forests (69.1%). Forest dependency is mainly subsistence-oriented for meeting basic household requirements. Livestock population, cultivated land per household, and non-usage of alternative fuels are the major explanatory drivers of forest dependency. Our findings can help decision and policy makers to establish nested governance mechanisms encouraging prioritized site-specific conservation options among forest-adjacent households. Additionally, income diversification with respect to alternate livelihood sources, institutional reforms, and infrastructure facilities can reduce forest dependency, thereby, allowing sustainable forest management.

  10. Vegetation composition and structure of southern coastal plain pine forests: An ecological comparison

    Science.gov (United States)

    Hedman, C.W.; Grace, S.L.; King, S.E.

    2000-01-01

    Longleaf pine (Pinus palustris) ecosystems are characterized by a diverse community of native groundcover species. Critics of plantation forestry claim that loblolly (Pinus taeda) and slash pine (Pinus elliottii) forests are devoid of native groundcover due to associated management practices. As a result of these practices, some believe that ecosystem functions characteristic of longleaf pine are lost under loblolly and slash pine plantation management. Our objective was to quantify and compare vegetation composition and structure of longleaf, loblolly, and slash pine forests of differing ages, management strategies, and land-use histories. Information from this study will further our understanding and lead to inferences about functional differences among pine cover types. Vegetation and environmental data were collected in 49 overstory plots across Southlands Experiment Forest in Bainbridge, GA. Nested plots, i.e. midstory, understory, and herbaceous, were replicated four times within each overstory plot. Over 400 species were identified. Herbaceous species richness was variable for all three pine cover types. Herbaceous richness for longleaf, slash, and loblolly pine averaged 15, 13, and 12 species per m2, respectively. Longleaf pine plots had significantly more (p < 0.029) herbaceous species and greater herbaceous cover (p < 0.001) than loblolly or slash pine plots. Longleaf and slash pine plots were otherwise similar in species richness and stand structure, both having lower overstory density, midstory density, and midstory cover than loblolly pine plots. Multivariate analyses provided additional perspectives on vegetation patterns. Ordination and classification procedures consistently placed herbaceous plots into two groups which we refer to as longleaf pine benchmark (34 plots) and non-benchmark (15 plots). Benchmark plots typically contained numerous herbaceous species characteristic of relic longleaf pine/wiregrass communities found in the area. Conversely

  11. The status of our scientific understanding of lodgepole pine and mountain pine beetles - a focus on forest ecology and fire behavior

    Science.gov (United States)

    Merrill R. Kaufmann; Gregory H. Aplet; Michael G. Babler; William L. Baker; Barbara Bentz; Michael Harrington; Brad C. Hawkes; Laurie Stroh Huckaby; Michael J. Jenkins; Daniel M. Kashian; Robert E. Keane; Dominik Kulakowski; Ward McCaughey; Charles McHugh; Jose Negron; John Popp; William H. Romme; Wayne Shepperd; Frederick W. Smith; Elaine Kennedy Sutherland; Daniel Tinker; Thomas T. Veblen

    2008-01-01

    Mountain pine beetle populations have reached outbreak levels in lodgepole pine forests throughout North America. The geographic focus of this report centers on the southern Rocky Mountains of Colorado and southern Wyoming. The epidemic extends much more widely, however, from the southern Rocky Mountains in Colorado in the United States to the northern Rocky Mountains...

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

    Science.gov (United States)

    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...

  13. Forest stand dynamics of shortleaf pine in the Ozarks

    Science.gov (United States)

    David R. Larsen

    2007-01-01

    Much has been written on the management of shortleaf pine in the Ozarks (Brinkman et al. 1965, Brinkman 1967, Brinkman and Smith 1968, Seidel and Rogers 1965, Seidel and Rogers 1966). In large portions of the Ozarks, shortleaf pine does not grow in pure stands but rather in mixes with various oak species. These mixes present unique challenges in finding the set of...

  14. Silvicultural recommendations for the management of ponderosa pine forest

    Science.gov (United States)

    Martin Alfonso Mendoza Briseno; Mary Ann Fajvan; Juan Manuel Chacon Sotelo; Alejandro Velazquez Martinez; Antonio Quinonez. Silva

    2014-01-01

    Ponderosa pines are the most important timber producing species in Mexico, and they also represent a major portion of the Usa and Canada timber production. These pines form near pure stands with simple and stable stand structure. They suffer only occasional disturbances, and they sustain a limited capacity to hold biodiversity and other senvironmental services. The...

  15. Establishing Pine Monocultures and Mixed Pine-Hardwood Stands on Reclaimed Surface Mined Land in Eastern Kentucky: Implications for Forest Resilience in a Changing Climate

    Directory of Open Access Journals (Sweden)

    Geoffrey Bell

    2017-10-01

    Full Text Available Surface mining and mine reclamation practices have caused significant forest loss and forest fragmentation in Appalachia. Shortleaf pine (Pinus echinata is threatened by a variety of stresses, including diseases, pests, poor management, altered fire regimes, and climate change, and the species is the subject of a widescale restoration effort. Surface mines may present opportunity for shortleaf pine restoration; however, the survival and growth of shortleaf pine on these harsh sites has not been critically evaluated. This paper presents first-year survival and growth of native shortleaf pine planted on a reclaimed surface mine, compared to non-native loblolly pine (Pinus taeda, which has been highly successful in previous mined land reclamation plantings. Pine monoculture plots are also compared to pine-hardwood polyculture plots to evaluate effects of planting mix on tree growth and survival, as well as soil health. Initial survival of shortleaf pine is low (42%, but height growth is similar to that of loblolly pine. No differences in survival or growth were observed between monoculture and polyculture treatments. Additional surveys in coming years will address longer-term growth and survival patterns of these species, as well as changes to relevant soil health endpoints, such as soil carbon.

  16. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon.

    Directory of Open Access Journals (Sweden)

    Michelle C Agne

    Full Text Available Lodgepole pine (Pinus contorta forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21-28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its

  17. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon.

    Science.gov (United States)

    Agne, Michelle C; Shaw, David C; Woolley, Travis J; Queijeiro-Bolaños, Mónica E

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum) also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21-28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its potential to

  18. Changes in forest structure since 1860 in ponderosa pine dominated forests in the Colorado and Wyoming Front Range, USA

    Science.gov (United States)

    Mike A. Battaglia; Benjamin Gannon; Peter M. Brown; Paula J. Fornwalt; Antony S. Cheng; Laurie S. Huckaby

    2018-01-01

    Management practices since the late 19th century, including fire exclusion and harvesting, have altered the structure of ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) dominated forests across the western United States. These structural changes have the potential to contribute to uncharacteristic wildfire behavior and effects. Locally-...

  19. Manganese in the litter fall-forest floor continuum of boreal and temperate pine and spruce forest ecosystems

    DEFF Research Database (Denmark)

    Berg, Björn; Erhagen, Björn; Johansson, Maj-Britt

    2015-01-01

    We have reviewed the literature on the role of manganese (Mn) in the litter fall-to-humus subsystem. Available data gives a focus on North European coniferous forests. Manganese concentrations in pine (Pinus spp.) foliar litter are highly variable both spatially and temporally within the same lit...

  20. Comparison of bacterial and fungal communities between natural and planted pine forests in subtropical China.

    Science.gov (United States)

    Nie, Ming; Meng, Han; Li, Ke; Wan, Jia-Rong; Quan, Zhe-Xue; Fang, Chang-Ming; Chen, Jia-Kuan; Li, Bo

    2012-01-01

    To improve our understanding of the changes in bacterial and fungal diversity in natural pine and planted forests in subtropical region of China, we examined bacterial and fungal communities from a native and a nearby planted pine forest of the Mt. Lushan by constructing clone libraries of 16S and 18S rRNA genes. For bacterial communities, Proteobacteria and Acidobacteria were dominant bacterial taxa in both two types of forest soils. The Shannon-Wiener diversity index, rarefaction curve analysis, and LibShuff analysis suggest that these two forests contained similar diversity of bacterial communities. Low soil acidity (pH ≈ 4) of our study forests might be one of the most important selection factors determining growth of acidophilic Acidobacteria and Proteobacteria. However, the natural forest harbored greater level of fungal diversity than the planted forest according to the Shannon-Wiener diversity index and rarefaction curve analysis. Basidiomycota and Ascomycota were dominant fungal taxa in the soils of natural and planted forests, respectively. Our results suggest that fungal community was more sensitive than the bacterial community in characterizing the differences in plant cover impacts on the microbial flora in the natural and planted forests. The natural and planted forests may function differently due to the differences in soil fungal diversity and relative abundance.

  1. Resiliency of an Interior Ponderosa Pine Forest to Bark Beetle Infestations Following Fuel-Reduction and Forest-Restoration Treatments

    Directory of Open Access Journals (Sweden)

    Christopher J. Fettig

    2014-01-01

    Full Text Available Mechanical thinning and the application of prescribed fire are commonly used to restore fire-adapted forest ecosystems in the Western United States. During a 10-year period, we monitored the effects of fuel-reduction and forest-restoration treatments on levels of tree mortality in an interior ponderosa pine, Pinus ponderosa Dougl. ex Laws., forest in California. Twelve experimental plots, ranging in size from 77–144 ha, were established to create two distinct forest structural types: mid-seral stage (low structural diversity; LoD and late-seral stage (high structural diversity; HiD. Following harvesting, half of each plot was treated with prescribed fire (B. A total of 16,473 trees (8.7% of all trees died during the 10-year period. Mortality was primarily attributed to bark beetles (Coleoptera: Curculionidae, Scolytinae (10,655 trees, specifically fir engraver, Scolytus ventralis LeConte, mountain pine beetle, Dendroctonus ponderosae Hopkins, western pine beetle, D. brevicomis LeConte, pine engraver, Ips pini (Say, and, to a much lesser extent, Jeffrey pine beetle, D. jeffreyi Hopkins. Trees of all ages and size classes were killed, but mortality was concentrated in the smaller-diameter classes (19–29.2 and 29.3–39.3 cm at 1.37 m in height. Most mortality occurred three to five years following prescribed burns. Higher levels of bark beetle-caused tree mortality were observed on LoD + B (8.7% than LoD (4.2%. The application of these and other results to the   management of interior P. ponderosa forests are discussed, with an emphasis on the maintenance of large trees.

  2. Effects of a Severe Mountain Pine Beetle Epidemic in Western Alberta, Canada under Two Forest Management Scenarios

    Directory of Open Access Journals (Sweden)

    Richard R. Schneider

    2010-01-01

    Full Text Available We used a simulation model to investigate possible effects of a severe mountain pine beetle (Dendroctonus ponderosae Hopkins epidemic under two management scenarios in Alberta, Canada. Our simulated outbreak was based on the current epidemic in British Columbia, which may kill close to 80% of the province's pine volume. Our two management scenarios were conventional harvest and a pine-reduction strategy modeled on a component of Alberta's Mountain Pine Beetle Management Strategy. The pine strategy seeks to reduce the number of susceptible pine stands by 75% over the next 20 years through targeted harvesting by the forest industry. Our simulations showed that the pine strategy could not be effectively implemented, even if the onset of the beetle outbreak was delayed for 20 years. Even though we increased mill capacity by 20% and directed all harvesting to high volume pine stands during the pine strategy's surge cut, the amount of highly susceptible pine was reduced by only 43%. Additional pine volume remained within mixed stands that were not targeted by the pine strategy. When the outbreak occurred in each scenario, sufficient pine remained on the landscape for the beetle to cause the timber supply to collapse. Alternative management approaches and avenues for future research are discussed.

  3. Hydrologic Effects of Global Climate Change on a Large Drained Pine Forest

    Science.gov (United States)

    Devendra M. Amatya; Ge Sun; R. W. Skaggs; G. M Chescheir; J. E. Nettles

    2006-01-01

    A simulation study using a watershed scale forest hydrology model (DRAINWAT) was conducted to evaluate potential effects of climate change on the hydrology of a 3,000 ha managed pine forest in coastal North Carolina. The model was first validated with a five-year (1996-2000) data set fro111 the study site and then run with 50-years (1951-00) of historic weather data...

  4. Restoration of the Native Plant Communities in Longleaf Pine Landscapes on the Kisatchie National Forest, Louisiana

    Science.gov (United States)

    James D. Haywood; Alton Martin; Finis L. Harris; Michael L. Elliott-Smith

    1998-01-01

    In January 1993, the Kisatchie National Forest and Southern Research Station began monitoring the effects of various management practices on overstory and midstory trees, shrubs, and understory woody and herbaceous vegetation in several longleaf pine (Pinus palustris Mill.) stands. The monitoring of these stands is part of several Ecosystem...

  5. Fire frequency effects on fuel loadings in pine-oak forests of the Madrean Province

    Science.gov (United States)

    Francisco J. Escobedo; Peter F. Ffolliott; Gerald J. Gottfried; Florentino Garza

    2001-01-01

    Loadings of downed woody fuels in pine-oak forests of the Madrean Province are heavier on sites in southeastern Arizona with low fire frequencies and lower on sites in northeastern Sonora, Mexico, with high fire frequencies. Low fire frequencies in southeastern Arizona are attributed largely to past land uses and the fire suppression policies of land management...

  6. Variability of fire behavior, fire effects, and emissions in Scotch pine forests of central Siberia

    Science.gov (United States)

    D. J. McRae; Susan Conard; G. A. Ivanova; A. I. Sukhinin; Steve Baker; Y. N. Samsonov; T. W. Blake; V. A. Ivanov; A. V. Ivanov; T. V. Churkina; WeiMin Hao; K. P. Koutzenogij; Nataly Kovaleva

    2006-01-01

    As part of the Russian FIRE BEAR (Fire Effects in the Boreal Eurasia Region) Project, replicated 4-ha experimental fires were conducted on a dry Scotch pine (Pinus sylvestris)/lichen (Cladonia sp.)/feathermoss (Pleurozeum schreberi) forest site in central Siberia. Observations from the initial seven surface fires (2000-2001) ignited under a range of burning...

  7. Population growth and the decline of natural Southern yellow pine forests

    Science.gov (United States)

    David B. South; Edward R. Buckner

    2004-01-01

    Population growth has created social and economic pressures that affect the sustainability of naturally regenerated southern yellow pine forests. Major causes of this decline include (1) a shift in public attitudes regarding woods burning (from one favoring it to one that favors fire suppression) and (2) an increase in land values (especially near urban centers). The...

  8. Modeling precipitation-runoff relationships to determine water yield from a ponderosa pine forest watershed

    Science.gov (United States)

    Assefa S. Desta

    2006-01-01

    A stochastic precipitation-runoff modeling is used to estimate a cold and warm-seasons water yield from a ponderosa pine forested watershed in the north-central Arizona. The model consists of two parts namely, simulation of the temporal and spatial distribution of precipitation using a stochastic, event-based approach and estimation of water yield from the watershed...

  9. Dendroclimatic signals deduced from riparian versus upland forest interior pines in North Karelia, Finland

    DEFF Research Database (Denmark)

    Helama, Samuli; Arentoft, Birgitte W.; Collin-Haubensak, Olivier

    2013-01-01

    Radial growth of boreal tree species is only rarely studied in riparian habitats. Here we investigated chronologies of earlywood, latewood, and annual ring widths and blue intensity (BI; a surrogate to latewood density) from riparian lake shore and upland forest interior pines (Pinus sylvestris L...

  10. Summary (Songbird ecology in southwestern ponderosa pine forests: A literature review)

    Science.gov (United States)

    William M. Block; Deborah M. Finch; Joseph L. Ganey; William H. Moir

    1997-01-01

    Most ornithological studies in Southwestern ponderosa pine forests have yielded results that are applicable only to the specific location and particular conditions of the study areas (for example, Green 1979 and Hurlbert 1984). In addition, varying interpretation of similar study results by investigators has limited our ability to extend or synthesize research results...

  11. Short Communication. Resin tapping activity as a contribution to the management of maritime pine forest

    Energy Technology Data Exchange (ETDEWEB)

    Palma, A.; Pereira, J.M.; Soares, P.

    2016-07-01

    Aim of the study: In this work potential resin yield in a region of high forest ability where maritime pine is the main species was estimated in order to understand the viability of promoting resin exploitation. Area of study: This study was conducted in Castro Da ire County in central region of Portugal. Material and methods: To quantify the resin yield of trees tapped for the first time two plots were installed in a maritime pine stand with average tree age 65 years. Before the beginning of the resin tapping, dendrometric tree variables were measured. Also, in a neighbouring stand, 25 trees were selected to check the relation between tree dbh and resin yield. Gum resin from every tree was weighted during the season. Estimates of potential resin yield in Castro Daire County were made based on data from National Forest Inventory plots, resin tapping legislation and resin yield values obtained in the field. Two scenarios were considered: high and low resin yield. To understand the intentions of forest owners towards restarting resin tapping activity 16 maritime pine forest owners were interviewed. Main results: The results point out a high yield potential capacity for gum resin production in the County: values between 2,025 and 5,873 tons were obtained. Research highlights: Results may highlight the important socio-economical role of the resin tapping activity and can be used to support national forest policies to the resin sector and give forest owners motivation to reactivate resin tapping activity. (Author)

  12. Soil Respiration Declines Following Beetle - Induced Forest Mortality in a Lodgepole Pine Forest

    Science.gov (United States)

    Borkhuu, B.; Peckham, S. D.; Norton, U.; Ewers, B. E.; Pendall, E.

    2014-12-01

    Lodgepole pine (Pinus contorta var. latifolia) forests in northern Colorado and southeast Wyoming have been undergoing a major mortality event owing to mountain pine beetle (Dendroctonus ponderosae) infestation since 2007. We studied biotic and abiotic drivers of growing season soil respiration in four mature stands experiencing different levels of mortality between 2008 and 2012 in the Medicine Bow Mountains, southeastern Wyoming, USA. For five years, beetle infestation significantly altered forest structure. Stand mortality was 30% and more than 80% in stands with the lowest and highest mortality, respectively. Understory vegetation cover increased by 50% for five years following beetle infestation. Needlefall was increased by more than 50% during first two years of beetle infestation compared to the pre-disturbance period. We did not observe an immediate increase in soil respiration following beetle infestation as suggested by some researchers. Soil respiration rates in midsummer ranged from 1.4 ± 0.1 μmol m-2 s-1 in stands with highest mortality to 3.1 ± 0.2 μmol m-2s-1 in uninfested stand. Live tree basal area was the dominant factor controlling soil respiration, explaining more than 60% of the interannual and spatial variations in response to the disturbance. In addition, soil respiration was significantly correlated with fine root biomass, which explained 55% of variations, providing strong evidence that autotrophic respiration dominated the forest soil respiration flux. Furthermore, the seasonality of soil respiration was controlled mainly by mean monthly precipitation and mid-day photosynthetically active radiation. Each factor predicted from 30% to 50% of seasonal soil respiration variability with the highest correlation coefficients in stand with the lowest mortality. Our results clearly indicate that the reduction of photosynthesis in trees over the infestation period significantly reduced soil respiration. The remaining activity in dead stands may

  13. [Effect of pine plantations on soil arthropods in a high Andean forest].

    Science.gov (United States)

    León-Gamboa, Alba Lucía; Ramos, Carolina; García, Mary Ruth

    2010-09-01

    One of the most common problems in the Colombian mountains has been the replacement of native vegetation by pine plantations. Soil arthropods are a fundamental component of forest ecosystem, since they participate in the organic matter fragmentation, previous to decomposition. This role is more valuable in high altitude environments, where low temperatures limit the dynamics of biological processes, where the effects of pine plantations on soil arthropods are still not well-known. In a remnant of high-andean forest (Neusa - Colombia) and a pine plantation of about 50 years-old, it was evaluated the composition, richness and abundance of arthropods at surface (S), organic horizon (O) and mineral horizon (A) of soil, to establish the differences associated to the soil use transformation. It was used "Pitfall" sampling to register the movement of the epigeous fauna, and extraction by funnel Berlese for determining the fauna density from O and A horizons. The Shannon and Simpson indexes estimated the diversity at different places and horizons, and the trophic structure of the community was evaluated. Overall, there were collected 38 306 individuals from forest and 17 386 individuals from pine plantation, mainly distributed in Collembola (42.4%), Acari (27%), Diptera (17.6%) and Coleoptera (4.6%). The most important differences were given in the surface, where the mobilization in forest (86 individuals/day) almost triplicates the one in pine plantation (33 individuals/day). The differences in composition were given in Collembola, Araneae, Hemiptera, Homoptera and Hymenoptera. The dynamics of richness and abundance along the year had significant high values in the native forest than in the pine plantation. The general trophic structure was dominated by saprophagous (75%), followed by predators (14%) and phytophagous (9%), but in two layers of the pine plantation soil (S and O) this structural pattern was not given. Based on the results, it was concluded that pine

  14. Persistence of evapotranspiration impacts from mountain pine beetle outbreaks in lodgepole pine forests, south-central Rocky Mountains, USA

    Science.gov (United States)

    Vanderhoof, Melanie; Williams, Christopher

    2014-05-01

    The current extent and high severity (percent tree mortality) of mountain pine beetle outbreaks across western North America have been attributed to regional climate change, specifically warmer summer and winter temperatures and drier summers. These outbreaks are widespread and have potentially persistent impacts on forest evapotranspiration. The few data-driven studies have largely been restricted by the temporal availability of remote sensing products. This study utilized multiple mountain pine beetle outbreak location datasets, both current and historical, within lodgepole pine stands in the south-central Rocky Mountains. The full seasonal evapotranspiration impact of outbreak events for decades after outbreak (0 to 60 years) and the role of outbreak severity in determining that impact were quantified. We found a 30% reduction in evapotranspiration peaking at 14-20 years post-outbreak during the spring snowmelt period, when water was not limited, but a minimal reduction in evapotranspiration during the remainder of the growing season (June - August). We also found a significant increase in evapotranspiration, relative to non-attacked stands, in intermediate aged stands (20-40 years post-disturbance) corresponding with a peak in LAI and therefore transpiration. During the snow-cover months evapotranspiration initially increased with needle fall and snag fall and corresponding increases in albedo and shortwave transmission to the surface. We found that changes in evapotranspiration during all seasons dissipated by 60 years post-attack. MODIS evapotranspiration values responded most strongly to mountain pine beetle driven changes in net radiation or available energy, and vegetation cover (e.g. LAI, fPAR and EVI). It also appears that the post-attack response of evapotranspiration may be sensitive to precipitation patterns and thus the consequences of a disturbance event may depend on the directionality of climate change conditions.

  15. Season of prescribed burn in ponderosa pine forests in eastern Oregon: impact on pine mortality.

    Science.gov (United States)

    Walter G. Thies; Douglas J. Westlind; Mark. Loewen

    2005-01-01

    A study of the effects of season of prescribed burn on tree mortality was established in mixed-age ponderosa pine (Pinus ponderosa Dougl. ex Laws.) at the south end of the Blue Mountains near Burns, Oregon. Each of six previously thinned stands was subdivided into three experimental units and one of three treatments was randomly assigned to each:...

  16. Forested communities of the pine mountain region, Georgia, USA

    Science.gov (United States)

    Robert Floyd; Robert Carter

    2013-01-01

    Seven landscape scale communities were identified in the Pine Mountain region having a mixture of Appalachian, Piedmont, and Coastal Plain species. The diagnostic environmental variables included elevation, B-horizon depth, A-horizon silt, topographic relative moisture index, and A-horizon potassium (K).

  17. Soil water regime under homogeneous eucalyptus and pine forests

    International Nuclear Information System (INIS)

    Lima, W.P.; Reichardt, K.

    1977-01-01

    Measurement of precipitation and monthly soil water content during two consecutive years, in 6-year old plantations of eucalypt and pine, and also in an open plot containing natural herbaceous vegetation, were used to compare the soil water regime of these vegetation covers. Precipitation was measured in the open plot with a recording and a non-recording rain gage. Soil water was assessed by the neutron scattering technique to a depth of 1,80 meters. Results indicate that there was, in general, water available in the soil over the entire period of study in all three vegetation conditions. The annual range of soil water in eucalypt, pine, and in natural herbaceous vegetation was essentially similar. The analysis of the average soil water regime showed that the soil under herbaceous vegetation was, generally, more umid than the soil under eucalypt and pine during the period of soil water recharge (September through February); during the period of soil water depletion, the opposite was true. Collectively, the results permit the conclusion that there were no adverse effects on the soil water regime which could be ascribed to reflorestation with eucalypt or pine, as compared with that observed for the natural herbaceous vegetation [pt

  18. A multi-century analysis of disturbance dynamics in pine-oak forests of the Missouri Ozark Highlands

    Science.gov (United States)

    Chad King; Rose-Marie. Muzika

    2013-01-01

    Using dendrochronology and growth release approaches, we analyzed the disturbance history of shortleaf pine (Pinus echinata Mich.) white oak (Quercus alba L.) forests in the Missouri Ozark Highlands. The objectives of this study were to (1) identify growth release events using living and remnant shortleaf pine and white oak, (2)...

  19. Earthworms, arthropods and plant litter decomposition in aspen (Populus tremuloides) and lodgepole pine(Pinus contorta) forests in Colorado, USA

    Science.gov (United States)

    Grizelle Gonzalez; Timothy R. Seastedt; Zugeily Donato

    2003-01-01

    We compared the abundance and community composition of earthworms, soil macroarthropods, and litter microarthropods to test faunal effects on plant litter decomposition rates in two forests in the subalpine in Colorado, USA. Litterbags containing recently senesced litter of Populus tremuloides (aspen) and Pinus contorta (lodgepole pine) were placed in aspen and pine...

  20. Effects of mountain pine beetle on fuels and expected fire behavior in lodgepole pine forests, Colorado, USA.

    Science.gov (United States)

    Schoennagel, Tania; Veblen, Thomas T; Negron, José F; Smith, Jeremy M

    2012-01-01

    In Colorado and southern Wyoming, mountain pine beetle (MPB) has affected over 1.6 million ha of predominantly lodgepole pine forests, raising concerns about effects of MPB-caused mortality on subsequent wildfire risk and behavior. Using empirical data we modeled potential fire behavior across a gradient of wind speeds and moisture scenarios in Green stands compared three stages since MPB attack (Red [1-3 yrs], Grey [4-10 yrs], and Old-MPB [∼30 yrs]). MPB killed 50% of the trees and 70% of the basal area in Red and Grey stages. Across moisture scenarios, canopy fuel moisture was one-third lower in Red and Grey stages compared to the Green stage, making active crown fire possible at lower wind speeds and less extreme moisture conditions. More-open canopies and high loads of large surface fuels due to treefall in Grey and Old-MPB stages significantly increased surface fireline intensities, facilitating active crown fire at lower wind speeds (>30-55 km/hr) across all moisture scenarios. Not accounting for low foliar moistures in Red and Grey stages, and large surface fuels in Grey and Old-MPB stages, underestimates the occurrence of active crown fire. Under extreme burning conditions, minimum wind speeds for active crown fire were 25-35 km/hr lower for Red, Grey and Old-MPB stands compared to Green. However, if transition to crown fire occurs (outside the stand, or within the stand via ladder fuels or wind gusts >65 km/hr), active crown fire would be sustained at similar wind speeds, suggesting observed fire behavior may not be qualitatively different among MPB stages under extreme burning conditions. Overall, the risk (probability) of active crown fire appears elevated in MPB-affected stands, but the predominant fire hazard (crown fire) is similar across MPB stages and is characteristic of lodgepole pine forests where extremely dry, gusty weather conditions are key factors in determining fire behavior.

  1. Effects of Mountain Pine Beetle on Fuels and Expected Fire Behavior in Lodgepole Pine Forests, Colorado, USA

    Science.gov (United States)

    Schoennagel, Tania; Veblen, Thomas T.; Negron, José F.; Smith, Jeremy M.

    2012-01-01

    In Colorado and southern Wyoming, mountain pine beetle (MPB) has affected over 1.6 million ha of predominantly lodgepole pine forests, raising concerns about effects of MPB-caused mortality on subsequent wildfire risk and behavior. Using empirical data we modeled potential fire behavior across a gradient of wind speeds and moisture scenarios in Green stands compared three stages since MPB attack (Red [1–3 yrs], Grey [4–10 yrs], and Old-MPB [∼30 yrs]). MPB killed 50% of the trees and 70% of the basal area in Red and Grey stages. Across moisture scenarios, canopy fuel moisture was one-third lower in Red and Grey stages compared to the Green stage, making active crown fire possible at lower wind speeds and less extreme moisture conditions. More-open canopies and high loads of large surface fuels due to treefall in Grey and Old-MPB stages significantly increased surface fireline intensities, facilitating active crown fire at lower wind speeds (>30–55 km/hr) across all moisture scenarios. Not accounting for low foliar moistures in Red and Grey stages, and large surface fuels in Grey and Old-MPB stages, underestimates the occurrence of active crown fire. Under extreme burning conditions, minimum wind speeds for active crown fire were 25–35 km/hr lower for Red, Grey and Old-MPB stands compared to Green. However, if transition to crown fire occurs (outside the stand, or within the stand via ladder fuels or wind gusts >65 km/hr), active crown fire would be sustained at similar wind speeds, suggesting observed fire behavior may not be qualitatively different among MPB stages under extreme burning conditions. Overall, the risk (probability) of active crown fire appears elevated in MPB-affected stands, but the predominant fire hazard (crown fire) is similar across MPB stages and is characteristic of lodgepole pine forests where extremely dry, gusty weather conditions are key factors in determining fire behavior. PMID:22272268

  2. A Prospectus on Restoring Late Successional Forest Structure to Eastside Pine Ecosystems Through Large-Scale, Interdisciplinary Research

    Science.gov (United States)

    Steve Zack; William F. Laudenslayer; Luke George; Carl Skinner; William Oliver

    1999-01-01

    At two different locations in northeast California, an interdisciplinary team of scientists is initiating long-term studies to quantify the effects of forest manipulations intended to accelerate andlor enhance late-successional structure of eastside pine forest ecosystems. One study, at Blacks Mountain Experimental Forest, uses a split-plot, factorial, randomized block...

  3. Short Communication. Resin tapping activity as a contribution to the management of maritime pine forest

    Directory of Open Access Journals (Sweden)

    Amélia Palma

    2016-07-01

    Full Text Available Aim of the study: In this work potential resin yield in a region of high forest ability where maritime pine is the main species was estimated in order to understand the viability of promoting resin exploitation. Area of study: This study was conducted in Castro Daire County in central region of Portugal. Material and methods: To quantify the resin yield of trees tapped for the first time two plots were installed in a maritime pine stand with average tree age 65 years. Before the beginning of the resin tapping, dendrometric tree variables were measured. Also, in a neighbouring stand, 25 trees were selected to check the relation between tree dbh and resin yield. Gum resin from every tree was weighted during the season. Estimates of potential resin yield in Castro Daire County were made based on data from National Forest Inventory plots, resin tapping legislation and resin yield values obtained in the field. Two scenarios were considered: high and low resin yield. To understand the intentions of forest owners towards restarting resin tapping activity 16 maritime pine forest owners were interviewed. Main results: The results point out a high yield potential capacity for gum resin production in the County: values between 2,025 and 5,873 tons were obtained. Research highlights: Results may highlight the important socio-economical role of the resin tapping activity and can be used to support national forest policies to the resin sector and give forest owners motivation to reactivate resin tapping activity. Keywords: non-wood forest product; resin yield potential; forest owner.

  4. Are Scots pine forest edges particularly prone to drought-induced mortality?

    Science.gov (United States)

    Buras, Allan; Schunk, Christian; Zeiträg, Claudia; Herrmann, Corinna; Kaiser, Laura; Lemme, Hannes; Straub, Christoph; Taeger, Steffen; Gößwein, Sebastian; Klemmt, Hans-Joachim; Menzel, Annette

    2018-02-01

    Climate change is expected to exacerbate the frequency of drought-induced tree mortality world-wide. To better predict the associated change of species composition and forest dynamics on various scales and develop adequate adaptation strategies, more information on the mechanisms driving the often observed patchiness of tree die-back is needed. Although forest-edge effects may play an important role within the given context, only few corresponding studies exist. Here, we investigate the regional die-back of Scots pine in Franconia, Germany, after a hot and dry summer in 2015, thereby emphasizing possible differences in mortality between forest edge and interior. By means of dendroecological investigations and close-range remote sensing, we assess long-term growth performance and current tree vitality along five different forest-edge distance gradients. Our results clearly indicate a differing growth performance between edge and interior trees, associated with a higher vulnerability to drought, increased mortality rates, and lower tree vitality at the forest edge. Prior long-lasting growth decline of dead trees compared to live trees suggests depletion of carbon reserves in course of a long-term drought persisting since the 1990s to be the cause of regional Scots pine die-back. These findings highlight the forest edge as a potential focal point of forest management adaptation strategies in the context of drought-induced mortality.

  5. Structural and climatic determinants of demographic rates of Scots pine forests across the Iberian Peninsula.

    Science.gov (United States)

    Vilà-Cabrera, Albert; Martínez-Vilalta, Jordi; Vayreda, Jordi; Retana, Javier

    2011-06-01

    The demographic rates of tree species typically show large spatial variation across their range. Understanding the environmental factors underlying this variation is a key topic in forest ecology, with far-reaching management implications. Scots pine (Pinus sylvestris L.) covers large areas of the Northern Hemisphere, the Iberian Peninsula being its southwestern distribution limit. In recent decades, an increase in severe droughts and a densification of forests as a result of changes in forest uses have occurred in this region. Our aim was to use climate and stand structure data to explain mortality and growth patterns of Scots pine forests across the Iberian Peninsula. We used data from 2392 plots dominated by Scots pine, sampled for the National Forest Inventory of Spain. Plots were sampled from 1986 to 1996 (IFN2) and were resampled from 1997 to 2007 (IFN3), allowing for the calculation of growth and mortality rates. We fitted linear models to assess the response of growth and mortality rates to the spatial variability of climate, climatic anomalies, and forest structure. Over the period of approximately 10 years between the IFN2 and IFN3, the amount of standing dead trees increased 11-fold. Higher mortality rates were related to dryness, and growth was reduced with increasing dryness and temperature, but results also suggested that effects of climatic stressors were not restricted to dry sites only. Forest structure was strongly related to demographic rates, suggesting that stand development and competition are the main factors associated with demography. In the case of mortality, forest structure interacted with climate, suggesting that competition for water resources induces tree mortality in dry sites. A slight negative relationship was found between mortality and growth, indicating that both rates are likely to be affected by the same stress factors. Additionally, regeneration tended to be lower in plots with higher mortality. Taken together, our results

  6. Modeling the effects of forest management on in situ and ex situ longleaf pine forest carbon stocks

    Science.gov (United States)

    C.A. Gonzalez-Benecke; L.J. Samuelson; T.A. Martin; W.P. Cropper Jr; Kurt Johnsen; T.A. Stokes; John Butnor; P.H. Anderson

    2015-01-01

    Assessment of forest carbon storage dynamics requires a variety of techniques including simulation models. We developed a hybrid model to assess the effects of silvicultural management systems on carbon (C) budgets in longleaf pine (Pinus palustris Mill.) plantations in the southeastern U.S. To simulate in situ C pools, the model integrates a growth and yield model...

  7. Macromycetes diversity of pine-tree plantings on a post-fire forest site in Notecka Forest (NW Poland

    Directory of Open Access Journals (Sweden)

    Stefan Friedrich

    2014-08-01

    Full Text Available The article presents the results of a study on fungi in pine-tree plantings after the last great fire in Notecka Forest. The occurrence of 134 species of fungi and 3 species of myxomycetes was recorded in 25 permanent study areas investigated between 1993 and 1998. The particpalion of bio-ecological of macromycetes was described in the context of vegetation changes in the years following the fire.

  8. The frequency of forest fires in Scots pine stands of Tuva, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Ivanova, G A; Kukavskaya, E A [Russian Academy of Sciences, Siberian Branch, V N Sukachev Institute of Forest, Akademgorodok, Krasnoyarsk, 660036 (Russian Federation); Ivanov, V A [Siberian State Technological University, Krasnoyarsk, 660049 (Russian Federation); Soja, A J, E-mail: GAIvanova@ksc.krasn.r [National Institute of Aerospace, Resident at NASA Langley Research Center, MS 420, Hampton, VA 23681-2199 (United States)

    2010-01-15

    Forest fires resulting from long periods of drought cause extensive forest ecosystem destruction and can impact on the carbon balance and air quality and feed back to the climate system, regionally and globally. Past fire frequency is reconstructed for Tuvan Scots pine stands using dendrochronology and statistics. Central Tuvan Scots pine (Pinus sylvestris) stands are subject to annual fire regimes; however high intensity fires are rare but they are responsible for most of the damage. Low, medium, and high severity fires have shaped the multi-story Scots pine communities, locally and regionally. Fire type and frequency are directly related to weather and climate and are also dependent on anthropogenic influences. The primary dry period, which promotes fire ignition and spread, in Tuva occurs in April and May. In some years, the precipitation deficit combined with high air temperatures induces long periods of drought. Unlike the typical surface fire regime, forest fires that burn during these extreme droughts often become crown fires that result in substantial forest damage and carbon release. The mean fire interval (MFI) is found to be 10.4 years in Balgazyn stands, and the landscape-scale MFI is 22.4 years. High severity, stand-replacing crown fires have a longer MFI. The warmer and dryer weather that is predicted by global climate models is evident in Tuva, and we believe that these changes in weather and climate have resulted in increased fire intensity and severity, rather than fire frequency in the Tuvan region.

  9. The frequency of forest fires in Scots pine stands of Tuva, Russia

    International Nuclear Information System (INIS)

    Ivanova, G A; Kukavskaya, E A; Ivanov, V A; Soja, A J

    2010-01-01

    Forest fires resulting from long periods of drought cause extensive forest ecosystem destruction and can impact on the carbon balance and air quality and feed back to the climate system, regionally and globally. Past fire frequency is reconstructed for Tuvan Scots pine stands using dendrochronology and statistics. Central Tuvan Scots pine (Pinus sylvestris) stands are subject to annual fire regimes; however high intensity fires are rare but they are responsible for most of the damage. Low, medium, and high severity fires have shaped the multi-story Scots pine communities, locally and regionally. Fire type and frequency are directly related to weather and climate and are also dependent on anthropogenic influences. The primary dry period, which promotes fire ignition and spread, in Tuva occurs in April and May. In some years, the precipitation deficit combined with high air temperatures induces long periods of drought. Unlike the typical surface fire regime, forest fires that burn during these extreme droughts often become crown fires that result in substantial forest damage and carbon release. The mean fire interval (MFI) is found to be 10.4 years in Balgazyn stands, and the landscape-scale MFI is 22.4 years. High severity, stand-replacing crown fires have a longer MFI. The warmer and dryer weather that is predicted by global climate models is evident in Tuva, and we believe that these changes in weather and climate have resulted in increased fire intensity and severity, rather than fire frequency in the Tuvan region.

  10. Forest floor and mineral soil respiration rates in a northern Minnesota red pine chronosequence

    Science.gov (United States)

    Powers, Matthew; Kolka, Randall; Bradford, John B.; Palik, Brian J.; Jurgensen, Martin

    2018-01-01

    We measured total soil CO2 efflux (RS) and efflux from the forest floor layers (RFF) in red pine (Pinus resinosaAit.) stands of different ages to examine relationships between stand age and belowground C cycling. Soil temperature and RS were often lower in a 31-year-old stand (Y31) than in 9-year-old (Y9), 61-year-old (Y61), or 123-year-old (Y123) stands. This pattern was most apparent during warm summer months, but there were no consistent differences in RFF among different-aged stands. RFF represented an average of 4–13% of total soil respiration, and forest floor removal increased moisture content in the mineral soil. We found no evidence of an age effect on the temperature sensitivity of RS, but respiration rates in Y61 and Y123 were less sensitive to low soil moisture than RS in Y9 and Y31. Our results suggest that soil respiration’s sensitivity to soil moisture may change more over the course of stand development than its sensitivity to soil temperature in red pine, and that management activities that alter landscape-scale age distributions in red pine forests could have significant impacts on rates of soil CO2 efflux from this forest type.

  11. Climate change and forest plagues: the case of the pine

    OpenAIRE

    Seixas Arnaldo, P.; Oliveira, I.; Santos, J.; Leite, S.

    2011-01-01

    The pine processionary moth, Thaumetopoea pityocampa (Den. & Schiff.) (Lep., Thaumetopoeidae) is known as the most defoliating insect in Pinus and Cedrus in many countries. In the last three decades, climate change has led to a substantial expansion of its range and high attack rates in previously unaffected areas were observed. A 3-year analysis of the effect of several climatic elements on the T. pityocampa adult emergence was made and one climatic change scenario was tested in order to pre...

  12. Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests

    Science.gov (United States)

    Robles, Marcos D.; Marshall, Robert M.; O'Donnell, Frances; Smith, Edward B.; Haney, Jeanmarie A.; Gori, David F.

    2014-01-01

    The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0–3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide. PMID

  13. Effects of climate variability and accelerated forest thinning on watershed-scale runoff in southwestern USA ponderosa pine forests.

    Directory of Open Access Journals (Sweden)

    Marcos D Robles

    Full Text Available The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres of ponderosa pine (Pinus ponderosa forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment and modest when compared to mean annual runoff from the study watersheds (0-3%. Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

  14. Effects of climate variability and accelerated forest thinning on watershed-scale runoff in southwestern USA ponderosa pine forests.

    Science.gov (United States)

    Robles, Marcos D; Marshall, Robert M; O'Donnell, Frances; Smith, Edward B; Haney, Jeanmarie A; Gori, David F

    2014-01-01

    The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0-3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

  15. Longleaf pine restoration in context comparisons of frequent fire forests

    Science.gov (United States)

    Seth Bigelow; Michael C. Stambaugh; Joseph J. O' Brien; Andrew J. Larson; Michael A. Battaglia

    2018-01-01

    To see a frequent-fire forest burn for the first time is to experience a remarkable teat of nature. Most people are accustomed to the slow change of forests with the seasons, not the instantaneous conversion of green and brown plant mass to smoke and char. Yet to visit such a forest a week after it bums is to see bright green shoots emerging, highlighted against a...

  16. Thirty year change in lodgepole and lodgepole/mixed conifer forest structure following 1980s mountain pine beetle outbreak in western Colorado, USA

    Science.gov (United States)

    Kristen A. Pelz; Frederick W. Smith

    2012-01-01

    Current mortality in lodgepole pine caused by mountain pine beetle (MPB) throughout much of western North America has resulted in concern about future forest structure. To better understand the long-term effects of the current mortality, and how it might differ depending on forest species composition, we measured forest vegetation and woody fuel accumulations...

  17. Pine straw production: from forest to front yard

    Science.gov (United States)

    Janice F. Dyer; Rebecca J. Barlow; John S. Kush; John C. Gilbert

    2012-01-01

    Southern forestry may be undergoing a paradigm shift in which timber production is not necessarily the major reason for owning forested land. However, there remains interest in generating income from the land and landowners are exploring alternatives, including agroforestry practices and production of non-timber forest products (NTFPs). One such alternative more recent...

  18. Phospholipid fatty acid composition of microorganisms in pine forest soils of Central Siberia

    Czech Academy of Sciences Publication Activity Database

    Evgrafova, S.Yu.; Šantrůčková, H.; Shibistova, O.B.; Elhottová, Dana; Černá, B.; Zrazhevskaya, G.K.; Lloyd, D.

    2008-01-01

    Roč. 35, č. 5 (2008), s. 452-458 ISSN 1062-3590 Grant - others:Evropská unie(XE) 03-55-1344; Ministry of Education and Science of the Russian Federation(RU) RUX0-002-KR-06 Institutional research plan: CEZ:AV0Z60660521 Keywords : phospholipid fatty acid * microorganisms * pine forest soils Subject RIV: EH - Ecology, Behaviour Impact factor: 0.082, year: 2008

  19. Relationships between spectral and bird species rarefaction curves in a brutian pine forest ecosystem

    OpenAIRE

    Özdemir, İbrahim; Mert, Ahmet; Özkan, Ulaş Yunus; Aksan, Şengül; Ünal, Yasin

    2017-01-01

    This study aimed at determining the relations betweenspectral and bird species rarefaction curves in a brutian pine forest ecosystemlocated in the Fethiye region, Turkey. Bird species were counted by fieldworkin 40 sample plots with 0.81 ha (90 x 90 m). The NDVITOA values of pixelsbelonging to each plot (pixel numbers are 36, 81 and 324 for Aster, SPOT andRapidEye, respectively) were calculated. Spectral and bird species rarefactioncurves were formed by means of EstimatesS software. The relat...

  20. Understanding old-growth red and white pine dominated forests in Ontario. Forest fragmentation and biodiversity project technical report No. 2

    Energy Technology Data Exchange (ETDEWEB)

    Carleton, T.J.; Gordon, A.M.

    1992-01-01

    In summer 1991, a variety of forest stands dominated by old specimens of white pine and red pine were sampled across a representative portion of the species' range in northcentral Ontario. Plots were established in 40 stands of those surveyed to identify the salient structural components of old-growth, to survey the floristic composition (vascular plants and autotrophic non- vascular plants), to survey site characteristics, and to estimate the links in understorey alpha diversity with site conditions and stand structure. Long-term objectives include a definition of old- growth pine forest, recognition criteria, and prospective management options. Forest stand structure was enumerated through mapping, mensurational, and age estimation techniques. Forest vegetation, including over and understorey species, was non- destructively sampled and a range of data on stand and soil-site variables was also collected in conjunction with information on stand variables peculiar to old growth forests.

  1. Vertical zonation of soil fungal community structure in a Korean pine forest on Changbai Mountain, China.

    Science.gov (United States)

    Ping, Yuan; Han, Dongxue; Wang, Ning; Hu, Yanbo; Mu, Liqiang; Feng, Fujuan

    2017-01-01

    Changbai Mountain, with intact montane vertical vegetation belts, is located at a sensitive area of global climate change and a central distribution area of Korean pine forest. Broad-leaved Korean pine mixed forest (Pinus koraiensis as an edificator) is the most representative zonal climax vegetation in the humid region of northeastern China; their vertical zonation is the most intact and representative on Changbai Mountain. In this study, we analyzed the composition and diversity of soil fungal communities in the Korean pine forest on Changbai Mountain at elevations ranging from 699 to 1177 m using Illumina High-throughput sequencing. We obtained a total 186,663 optimized sequences, with an average length of 268.81 bp. We found soil fungal diversity index was decreased with increasing elevation from 699 to 937 m and began to rise after reaching 1044 m; the richness and evenness indices were decreased with an increase in elevation. Soil fungal compositions at the phylum, class and genus levels varied significantly at different elevations, but with the same dominant fungi. Beta-diversity analysis indicated that the similarity of fungal communities decreased with an increased vertical distance between the sample plots, showing a distance-decay relationship. Variation partition analysis showed that geographic distance (mainly elevation gradient) only explained 20.53 % of the total variation of fungal community structure, while soil physicochemical factors explained 69.78 %.

  2. Ecosystem carbon density and allocation across a chronosequence of longleaf pine forests.

    Science.gov (United States)

    Samuelson, Lisa J; Stokes, Thomas A; Butnor, John R; Johnsen, Kurt H; Gonzalez-Benecke, Carlos A; Martin, Timothy A; Cropper, Wendell P; Anderson, Pete H; Ramirez, Michael R; Lewis, John C

    2017-01-01

    Forests can partially offset greenhouse gas emissions and contribute to climate change mitigation, mainly through increases in live biomass. We quantified carbon (C) density in 20 managed longleaf pine (Pinus palustris Mill.) forests ranging in age from 5 to 118 years located across the southeastern United States and estimated above- and belowground C trajectories. Ecosystem C stock (all pools including soil C) and aboveground live tree C increased nonlinearly with stand age and the modeled asymptotic maxima were 168 Mg C/ha and 80 Mg C/ha, respectively. Accumulation of ecosystem C with stand age was driven mainly by increases in aboveground live tree C, which ranged from ecosystem C. Live root C (sum of below-stump C, ground penetrating radar measurement of lateral root C, and live fine root C) increased with stand age and represented 4-22% of ecosystem C. Soil C was related to site index, but not to stand age, and made up 39-92% of ecosystem C. Live understory C, forest floor C, downed dead wood C, and standing dead wood C were small fractions of ecosystem C in these frequently burned stands. Stand age and site index accounted for 76% of the variation in ecosystem C among stands. The mean root-to-shoot ratio calculated as the average across all stands (excluding the grass-stage stand) was 0.54 (standard deviation of 0.19) and higher than reports for other conifers. Long-term accumulation of live tree C, combined with the larger role of belowground accumulation of lateral root C than in other forest types, indicates a role of longleaf pine forests in providing disturbance-resistant C storage that can balance the more rapid C accumulation and C removal associated with more intensively managed forests. Although other managed southern pine systems sequester more C over the short-term, we suggest that longleaf pine forests can play a meaningful role in regional forest C management. © 2016 by the Ecological Society of America.

  3. Social demand for multiple benefits provided by Aleppo pine forest management in Catalonia, Spain

    DEFF Research Database (Denmark)

    Varela, Elsa; Jacobsen, Jette Bredahl; Mavsar, Robert

    2017-01-01

    This paper estimates the social demand for key benefits provided by Aleppo pine forests in Catalonia that can be enhanced by management. These so-called externalities are the side effects of forest management on citizens’ welfare and can be either positive or negative. The externalities addressed...... are: biodiversity (measured as the number of tree species), accessibility for practicing recreational activities, CO2 sequestration and annual burned area by wildfires. By the use of a choice experiment, an economic valuation method, we estimate in a joint manner people’s preferences...

  4. Effect of forest clear cuts on plant–pollinator interactions: the case of three ericaceous subshrubs in Lithuanian pine forests

    Directory of Open Access Journals (Sweden)

    Remigijus Daubaras

    2017-03-01

    Full Text Available Managed boreal pine forests are subject to regular clear cuts causing significant disturbances to these ecosystems. It is believed that, to some extent, they resemble natural cycles of forest growth, decline, and regeneration and can benefit, e.g., mutualistic relations among plants and pollinators. To study the impact of forest management (clear cuts on pollinator visitation, we focused on three ericaceous plant species, Vaccinium myrtillus, V. vitis-idaea, and Calluna vulgaris, common elements of pine forest understory. Our observations, conducted in Lithuania, showed that there are no differences among control mature stands and clear cut areas in terms of visitation frequency for all three studied species. However, at least for C. vulgaris, a shift toward fly visits was observed in the clear cut site, showing that open areas are preferred habitats for these insects. Ants constituted an important share of visitors to flowers of V. myrtillus and C. vulgaris, suggesting their important role in reproduction of these plant species.

  5. Effects of mountain pine beetle on fuels and expected fire behavior in lodgepole pine forests, Colorado, USA.

    Directory of Open Access Journals (Sweden)

    Tania Schoennagel

    Full Text Available In Colorado and southern Wyoming, mountain pine beetle (MPB has affected over 1.6 million ha of predominantly lodgepole pine forests, raising concerns about effects of MPB-caused mortality on subsequent wildfire risk and behavior. Using empirical data we modeled potential fire behavior across a gradient of wind speeds and moisture scenarios in Green stands compared three stages since MPB attack (Red [1-3 yrs], Grey [4-10 yrs], and Old-MPB [∼30 yrs]. MPB killed 50% of the trees and 70% of the basal area in Red and Grey stages. Across moisture scenarios, canopy fuel moisture was one-third lower in Red and Grey stages compared to the Green stage, making active crown fire possible at lower wind speeds and less extreme moisture conditions. More-open canopies and high loads of large surface fuels due to treefall in Grey and Old-MPB stages significantly increased surface fireline intensities, facilitating active crown fire at lower wind speeds (>30-55 km/hr across all moisture scenarios. Not accounting for low foliar moistures in Red and Grey stages, and large surface fuels in Grey and Old-MPB stages, underestimates the occurrence of active crown fire. Under extreme burning conditions, minimum wind speeds for active crown fire were 25-35 km/hr lower for Red, Grey and Old-MPB stands compared to Green. However, if transition to crown fire occurs (outside the stand, or within the stand via ladder fuels or wind gusts >65 km/hr, active crown fire would be sustained at similar wind speeds, suggesting observed fire behavior may not be qualitatively different among MPB stages under extreme burning conditions. Overall, the risk (probability of active crown fire appears elevated in MPB-affected stands, but the predominant fire hazard (crown fire is similar across MPB stages and is characteristic of lodgepole pine forests where extremely dry, gusty weather conditions are key factors in determining fire behavior.

  6. Ectomycorrhizal community structure of different genotypes of Scots pine under forest nursery conditions.

    Science.gov (United States)

    Leski, Tomasz; Aucina, Algis; Skridaila, Audrius; Pietras, Marcin; Riepsas, Edvardas; Rudawska, Maria

    2010-10-01

    In this paper, we report the effect of Scots pine genotypes on ectomycorrhizal (ECM) community and growth, survival, and foliar nutrient composition of 2-year-old seedlings grown in forest bare-root nursery conditions in Lithuania. The Scots pine seeds originated from five stands from Latvia (P1), Lithuania (P2 and P3), Belarus (P4), and Poland (P5). Based on molecular identification, seven ECM fungal taxa were identified: Suillus luteus and Suillus variegatus (within the Suilloid type), Wilcoxina mikolae, Tuber sp., Thelephora terrestris, Cenococcum geophilum, and Russuloid type. The fungal species richness varied between five and seven morphotypes, depending on seed origin. The average species richness and relative abundance of most ECM morphotypes differed significantly depending on pine origin. The most essential finding of our study is the shift in dominance from an ascomycetous fungus like W. mikolae in P2 and P4 seedlings to basidiomycetous Suilloid species like S. luteus and S. variegatus in P1 and P5 seedlings. Significant differences between Scots pine origin were also found in seedling height, root dry weight, survival, and concentration of C, K, Ca, and Mg in the needles. The Spearman rank correlation coefficient revealed that survival and nutritional status of pine seedlings were positively correlated with abundance of Suilloid mycorrhizas and negatively linked with W. mikolae abundance. However, stepwise multiple regression analysis showed that only survival and magnesium content in pine needles were significantly correlated with abundance of ECM fungi, and Suilloid mycorrhizas were a main significant predictor. Our results may have implications for understanding the physiological and genetic relationship between the host tree and fungi and should be considered in management decisions in forestry and ECM fungus inoculation programs.

  7. Influence of thinning intensity and canopy type on Scots pine stand and growth dynamics in a mixed managed forest

    Energy Technology Data Exchange (ETDEWEB)

    Primicia, I.; Artázcoz, R.; Imbert, J.B.; Puertas, F.; Traver, M.C.; Castillo, F.J.

    2016-07-01

    Aim of the study: We analysed the effects of thinning intensity and canopy type on Scots pine growth and stand dynamics in a mixed Scots pine-beech forest. Area of the study: Western Pyrenees. Material and methods: Three thinning intensities were applied in 1999 (0, 20 and 30% basal area removed) and 2009 (0, 20 and 40%) on 9 plots. Within each plot, pure pine and mixed pine-beech patches are distinguished. All pine trees were inventoried in 1999, 2009 and 2014. The effects of treatments on the tree and stand structure variables (density, basal area, stand and tree volume), on the periodic annual increment in basal area and stand and tree volume, and on mortality rates, were analysed using linear mixed effects models. Main Results: The enhancement of tree growth was mainly noticeable after the second thinning. Growth rates following thinning were similar or higher in the moderate than in the severe thinning. Periodic stand volume annual increments were higher in the thinned than in the unthinned plots, but no differences were observed between the thinned treatments. We observed an increase in the differences of the Tree volume annual increment between canopy types (mixed < pure) over time in the unthinned plots, as beech crowns developed. Research highlights: Moderate thinning is suggested as an appropriate forest practice at early pine age in these mixed forests, since it produced higher tree growth rates than the severe thinning and it counteracted the negative effect of beech on pine growth observed in the unthinned plots. (Author)

  8. Mountain pine beetle selectivity in old-growth ponderosa pine forests, Montana, USA.

    Science.gov (United States)

    Knapp, Paul A; Soulé, Peter T; Maxwell, Justin T

    2013-05-01

    A historically unprecedented mountain pine beetle (MPB) outbreak affected western Montana during the past decade. We examined radial growth rates (AD 1860-2007/8) of co-occurring mature healthy and MPB-infected ponderosa pine trees collected at two sites (Cabin Gulch and Kitchen Gulch) in western Montana and: (1) compared basal area increment (BAI) values within populations and between sites; (2) used carbon isotope analysis to calculate intrinsic water-use efficiency (iWUE) at Cabin Gulch; and (3) compared climate-growth responses using a suite of monthly climatic variables. BAI values within populations and between sites were similar until the last 20-30 years, at which point the visually healthy populations had consistently higher BAI values (22-34%) than the MPB-infected trees. These results suggest that growth rates two-three decades prior to the current outbreak diverged between our selected populations, with the slower-growing trees being more vulnerable to beetle infestation. Both samples from Cabin Gulch experienced upward trends in iWUE, with significant regime shifts toward higher iWUE beginning in 1955-59 for the visually healthy trees and 1960-64 for the MPB-infected trees. Drought tolerance also varied between the two populations with the visually healthy trees having higher growth rates than MPB-infected trees prior to infection during a multi-decadal period of drying summertime conditions. Intrinsic water-use efficiency significantly increased for both populations during the past 150 years, but there were no significant differences between the visually healthy and MPB-infected chronologies.

  9. Silvicultural systems and cutting methods for ponderosa pine forests in the Front Range of the central Rocky Mountains

    Science.gov (United States)

    Robert R. Alexander

    1986-01-01

    Guidelines are provided to help forest managers and silviculturists develop even- and/or uneven-aged cutting practices needed to convert old-growth and mixed ponderosa pine forests in the Front Range into managed stands for a variety of resource needs. Guidelines consider stand conditions, and insect and disease susceptibility. Cutting practices are designed to...

  10. A dendrochronological analysis of a disturbance-succession model for oak-pine forests of the Appalachian Mountains, USA

    Science.gov (United States)

    Patrick H. Brose; Thomas A. Waldrop

    2010-01-01

    Disturbance-succession models describe the relationship between the disturbance regime and the dominant tree species of a forest type. Such models are useful tools in ecosystem management and restoration, provided they are accurate. We tested a disturbance-succession model for the oak-pine (Quercus spp. - Pinus spp.) forests of the...

  11. Future Forests Webinar Series, Webinar Proceedings and Summary: Ongoing Research and Management Responses to the Mountain Pine Beetle Outbreak

    Science.gov (United States)

    M. Matonis; R. Hubbard; K. Gebert; B. Hahn; C. Regan

    2014-01-01

    The Future Forest Webinar Series facilitated dialogue between scientists and managers about the challenges and opportunities created by the mountain pine beetle (MPB) epidemic. The series consisted of six webinar facilitated by the USFS Rocky Mountain Research Station, the Northern and Rocky Mountain Regions, and the Colorado Forest Restoration Institute. The series...

  12. Effects of wildfire on densities of secondary cavity-nesting birds in ponderosa pine forests of northern Arizona

    Science.gov (United States)

    Jill K. Dwyer; William M. Block

    2000-01-01

    Many catastrophic wildfires burned throughout forests in Arizona during the spring and summer of 1996 owing to severely dry conditions. One result of these fires was a loss of preexisting tree cavities for reproduction. In ponderosa pine (Pinus ponderosa) forests most cavities are found in dead trees; therefore, snags are a very important habitat...

  13. Relationships between prescribed burning and wildfire occurrence and intensity in pine-hardwood forests in north Mississippi, USA

    Science.gov (United States)

    Stephen Brewer; Corey Rogers

    2006-01-01

    Using Geographic Information Systems and US Forest Service data, we examined relationships between prescribed burning (from 1979 to 2000) and the incidence, size, and intensity of wildfires (from 1995 to 2000) in a landscape containing formerly fire-suppressed, closed-canopy hardwood and pine-hardwood forests. Results of hazard (failure) analyses did not show an...

  14. Monoterpene emissions from a Ponderosa Pine forest. Does age matter?

    Science.gov (United States)

    Madronich, M. B.; Guenther, A. B.; Wessman, C. A.

    2011-12-01

    Determining the emissions rate of biogenic volatile organic carbon (BVOC) from plants is a challenge. Biological variability makes it difficult to assess accurately those emissions rates. It is known that photosynthetic active radiation (PAR), temperature, nutrients as well as the biology of the plant affect emissions. However, less is known about the variability of the emissions with respect to the life cycle of the plants. This study is focusing on the difference of monoterpene emission rates from mature Ponderosa Pine trees and saplings in the field. Preliminary calculations show that there is a significant difference between total monoterpene emissions in mature trees (0.24±0.04 μgC/gdwh) and saplings (0.37±0.02 μgC/gdwh).

  15. Present state and future trends of pine forests of malam jabba, swat district, Pakistan

    International Nuclear Information System (INIS)

    Siddiqui, M. F.; Arsalan, M.; Hussain, M. I.; Iqbal, J.; Wahab, M.

    2015-01-01

    Present state and future trend of pine forests of Malam Jabba, Swat district, Pakistan explored. We focused on vegetation composition, structure, diversity and forests dynamics. Thirteen stands were sampled by Point Centered Quarter method. Among all stands four monospecific forests of Pinus wallichiana attained highest density ha-1 except in one stand where Picea smithiana attained 401 trees ha-1. Unlike density, the basal area m2 ha-1 of these stands varies stand to stand. Based on floristic composition and importance value index, five different communities viz Pinus wallichiana-Picea smithiana; Picea smithiana-Pinus wallichiana; Abies pindrow-Pinus wallichiana; Pinus wallichiana-Abies pindrow; Abies pindrow-Picea smithiana and 4 monospecific forests of Pinus wallichiana were recognized. Size class structure of forests showed marked influence of anthropogenic disturbance because not a single stand showed ideal regeneration pattern (inverse J shape distribution). Future of these forests is worst due to absence trees in small size classes. Gaps are also evident in most of the forest stands. Stand diversity, richness, equitability and Simpson dominance values formulated on single stand basis. Diversity of Abides pindrow and Pinus wallichiana stand was highest because these stand occupied dominant species, while lowest diversity observed in some Pinus wallichiana and Picea smithiana stand as these stands have mark difference between the dominance of two species. In the monospecific forests, the diversity level was zero, suggesting the monopolization of resources by one species or elimination of other tree species in these stands. (author)

  16. Contrasting responses to drought of forest floor CO2 efflux in a loblolly pine plantation and a nearby Oak-Hickory forest

    Science.gov (United States)

    S. Palmroth; Chris A. Maier; Heather R. McCarthy; A. C. Oishi; H. S. Kim; Kurt H. Johnsen; Gabrial G. Katul; Ram Oren

    2005-01-01

    Forest floor C02 efflux (Fff) depends on vegetation type, climate, and soil physical properties. We assessed the effects of biological factors on Fff by comparing a maturing pine plantation (PP) and a nearby mature Oak-Hickory-type hardwood forest (HW). Fff was measured...

  17. Threats to North American Forests from Southern Pine Beetle with Warming Winters

    Science.gov (United States)

    Lesk, Corey; Coffel, Ethan; D'Amato, Anthony W.; Dodds, Kevin; Horton, Radley M.

    2016-01-01

    In coming decades, warmer winters are likely to lift range constraints on many cold-limited forest insects. Recent unprecedented expansion of the southern pine beetle (SPB, Dendroctonus frontalis) into New Jersey, New York, Connecticut, and Massachusetts in concert with warming annual temperature minima highlights the risk that this insect pest poses to the pine forests of the northern United States and Canada under continued climate change. Here we present the first projections of northward expansion in SPB-suitable climates using a statistical bioclimatic range modeling approach and current-generation general circulation model (GCM) output under the RCP 4.5 and 8.5 emissions scenarios. Our results show that by the middle of the 21st century, the climate is likely to be suitable for SPB expansion into vast areas of previously unaffected forests throughout the northeastern United States and into southeastern Canada. This scenario would pose a significant economic and ecological risk to the affected regions, including disruption oflocal ecosystem services, dramatic shifts in forest structure, and threats to native biodiversity.

  18. Meeting global policy commitments carbon sequestration and southern pine forests

    Science.gov (United States)

    Kurt H. Johnsen; David N. Wear; R. Oren; R.O. Teskey; Felipe Sanchez; Rodney E. Will; John Butnor; D. Markewitz; D. Richter; T. Rials; H.L. Allen; J. Seiler; D. Ellsworth; Christopher Maier; G. Katul; P.M. Dougherty

    2001-01-01

    In managed forests, the amount of carbon further sequestered will be determined by (1) the increased amount of carbon in standing biomass (resulting from land-use changes and increased productivity); (2) the amount of recalcitrant carbon remaining below ground at the end of rotations; and (3) the amount of carbon sequestered in products created from harvested wood....

  19. Role of de novo biosynthesis in ecosystem scale monoterpene emissions from a boreal Scots pine forest

    Directory of Open Access Journals (Sweden)

    R. Taipale

    2011-08-01

    Full Text Available Monoterpene emissions from Scots pine have traditionally been assumed to originate as evaporation from specialized storage pools. More recently, the significance of de novo emissions, originating directly from monoterpene biosynthesis, has been recognized. To study the role of biosynthesis at the ecosystem scale, we measured monoterpene emissions from a Scots pine dominated forest in southern Finland using the disjunct eddy covariance method combined with proton transfer reaction mass spectrometry. The interpretation of the measurements was based on a correlation analysis and a hybrid emission algorithm describing both de novo and pool emissions. During the measurement period May–August 2007, the monthly medians of daytime emissions were 200, 290, 180, and 200 μg m−2 h−1. The emissions were partly light dependent, probably due to de novo biosynthesis. The emission potential for both de novo and pool emissions exhibited a decreasing summertime trend. The ratio of the de novo emission potential to the total emission potential varied between 30 % and 46 %. Although the monthly changes were not significant, the ratio always differed statistically from zero, suggesting that the role of de novo biosynthesis was observable. Given the uncertainties in this study, we conclude that more accurate estimates of the contribution of de novo emissions are required for improving monoterpene emission algorithms for Scots pine dominated forests.

  20. Monterey MRWPCA Interceptor Pipeline 2008

    Data.gov (United States)

    California Natural Resource Agency — The Monterey Interceptor between Seaside Pump Station and Monterey Beach Resort is buried in the dunes, approximately 100 to 175 feet from the dune bluff. Between...

  1. Monterey MRWPCA Interceptor Pipeline 2008

    Data.gov (United States)

    California Department of Resources — The Monterey Interceptor between Seaside Pump Station and Monterey Beach Resort is buried in the dunes, approximately 100 to 175 feet from the dune bluff. Between...

  2. Phytosociological analysis of Pine forest at Indus Kohistan, KPK, Pakistan

    International Nuclear Information System (INIS)

    Khan, A.; Iqbal, J.

    2016-01-01

    The study was carried out to describe the pine communities at Indus Kohistan valley in quantitative term. Thirty stands of relatively undisturbed vegetation were selected for sampling. Quantitative sampling was carried out by Point Centered Quarter (PCQ) method. Seven tree species were common in the Indus Kohistan valley. Cedrus deodara was recorded from twenty eight different locations and exhibited the highest mean importance value while Pinus wallichiana was recorded from 23 different locations and exhibited second highest mean importance value. Third most occurring species was Abies pindrow that attained the third highest mean importance value and Picea smithiana was recorded from eight different locations and attained fourth highest importance value while it was first dominant in one stand and second dominant in four stands. Pinus gerardiana, Quercus baloot and Taxus fuana were the rare species in this area, these species attained low mean importance value. Six communities and four monospecific stands of Cedrus deodara were recognized. Cedrus-Pinus community was the most occurring community, which was recorded from 13 different stands. The second most occurring community in the study area was Abies Pinus wallichiana which was recorded from six locations while Cedrus-Picea and Abies-Picea communities were observed at two locations each. Pinus wallichiana - Picea and Cedrus-Pinus gerardiana communities were restricted to one location. (author)

  3. Evaluating the role of cutting treatments, fire and soil seed banks in an experimental framework in ponderosa pine forests of the Black Hills, South Dakota

    Science.gov (United States)

    Cody L. Wienk; Carolyn Hull Sieg; Guy R. McPherson

    2004-01-01

    Pinus ponderosa Laws. (ponderosa pine) forests have changed considerably during the past century, partly because recurrent fires have been absent for a century or more. A number of studies have explored the influence of timber harvest or burning on understory production in ponderosa pine forests, but study designs incorporating cutting and prescribed...

  4. Changes in soil respiration after thinning activities in dense Aleppo pine forests

    Science.gov (United States)

    Llovet, Joan; Alonso, Macià; Cerdà, Artemi

    2015-04-01

    Forest fires are a widespread perturbation in Mediterranean areas, and they have tended to increase during the last decades (Pausas, 2004; Moreno et al, 1998). Aleppo pine (Pinus halepensis Mill) is dominant specie in some forest landscapes of western Mediterranean Basin, due to its capacity to colonize abandoned fields, and also due to afforestation practices mainly performed during the 20th century (Ruiz Navarro et al., 2009). Aleppo pine tends to die as consequence of forest fires, although it is able to disperse a high quantity of seeds which easily germinates. These dispersion and germination can result in dense forests with high inter and intra-specific competition, low diversity, low growth, and high fuel accumulation, increasing the risk of new forest fires. These forests of high density present ecological problems and management difficulties that require preventive treatments. Thinning treatments are common in these types of communities, but the management has to be oriented towards strengthening their functions. In the context of global change, better understandings of the implications of forest management practices in the carbon cycle are necessary. The objective of this study was to examine the evolution of seasonal soil respiration after treatment of selective thinning in dense Aleppo pine forests. The study area covers three localities placed in the Valencian Community (E Spain) affected by a forest fire in 1994. Thinning activities were done 16 years after the fire, reducing pine density from around 100,000 individuals per hectare to around 900 individuals per hectare. Soil respiration was measured in situ with a portable soil respiration instrument (LI-6400, LiCor, Lincoln, NB, USA) fitted with a soil respiration chamber (6400-09, LiCor, Lincoln, NB, USA). We installed 12 plots per treatment (control and thinned) and locality, being a total of 72 plots. We carried out 13 measurements covering a period of one year. We also estimated other related

  5. Mountain Pine Beetle Dynamics and Reproductive Success in Post-Fire Lodgepole and Ponderosa Pine Forests in Northeastern Utah.

    Directory of Open Access Journals (Sweden)

    Andrew P Lerch

    Full Text Available Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae, but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug. and 599 ponderosa (Pinus ponderosa Doug. ex Law pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.

  6. Mountain Pine Beetle Dynamics and Reproductive Success in Post-Fire Lodgepole and Ponderosa Pine Forests in Northeastern Utah.

    Science.gov (United States)

    Lerch, Andrew P; Pfammatter, Jesse A; Bentz, Barbara J; Raffa, Kenneth F

    2016-01-01

    Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae), but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins) is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug.) and 599 ponderosa (Pinus ponderosa Doug. ex Law) pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.

  7. Belowground Competition Directs Spatial Patterns of Seedling Growth in Boreal Pine Forests in Fennoscandia

    Directory of Open Access Journals (Sweden)

    E. Petter Axelsson

    2014-09-01

    Full Text Available Aboveground competition is often argued to be the main process determining patterns of natural forest regeneration. However, the theory of multiple resource limitation suggests that seedling performance also depends on belowground competition and, thus, that their relative influence is of fundamental importance. Two approaches were used to address the relative importance of above- and below-ground competition on regeneration in a nutrient-poor pine (Pinus sylvestris boreal forest. Firstly, seedling establishment beneath trees stem-girdled 12 years ago show that a substantial proportion of the seedlings were established within two years after girdling, which corresponds to a time when nutrient uptake by tree roots was severely reduced without disrupting water transport to the tree canopy, which consequently was maintained. The establishment during these two years also corresponds to abundances high enough for normal stand replacement. Secondly, surveys of regeneration within forest gaps showed that surrounding forests depressed seedlings, so that satisfactory growth occurred only more than 5 m from forest edges and that higher solar radiation in south facing edges was not enough to mediate these effects. We conclude that disruption of belowground competitive interactions mediates regeneration and, thus, that belowground competition has a strong limiting influence on seedling establishment in these forests.

  8. Structure, disturbance, and change in the bristlecone pine forests of Colorado, U.S.A

    International Nuclear Information System (INIS)

    Baker, W.L.

    1992-01-01

    To analyze trends in the structure of forests dominated by Colorado bristlecone pine (Pinus aristata Bailey) the author sampled size class structures, collected environmental data, and determined the approximate year of origin of these forests at 65 sites scattered throughout the range of P. aristata in Colorado. Cluster analysis and detrended correspondence analysis (DCA) were used to identify major trends in the size class data. The size class data suggest that P. aristata is a long-lived species that primarily regenerates following fires. The DCA results suggest that (1) the major trend in variation in structure was related to time since disturbance, and (2) Populus tremuloides Michx. is present as numerous small stems in some of the P. aristata forests regardless of the age of these forests, a role for P. tremuloides that is at odds with the traditional view of this tree as primarily a seral species in the Rocky Mountains. Many P. aristata stands originated near A.D. 1900 and between A.D. 1625 and 1700. These were warm, dry periods that might have promoted fires, and they were also periods when sunspot numbers were low. The Southern Oscillation Index did not correlate with times of abundant stand origins. Although many P. aristata forests are over 500 yr old, these forests do not appear to be stable or unchanging

  9. Community occupancy responses of small mammals to restoration treatments in ponderosa pine forests, northern Arizona, USA.

    Science.gov (United States)

    Kalies, E L; Dickson, B G; Chambers, C L; Covington, W W

    2012-01-01

    In western North American conifer forests, wildfires are increasing in frequency and severity due to heavy fuel loads that have accumulated after a century of fire suppression. Forest restoration treatments (e.g., thinning and/or burning) are being designed and implemented at large spatial and temporal scales in an effort to reduce fire risk and restore forest structure and function. In ponderosa pine (Pinus ponderosa) forests, predominantly open forest structure and a frequent, low-severity fire regime constituted the evolutionary environment for wildlife that persisted for thousands of years. Small mammals are important in forest ecosystems as prey and in affecting primary production and decomposition. During 2006-2009, we trapped eight species of small mammals at 294 sites in northern Arizona and used occupancy modeling to determine community responses to thinning and habitat features. The most important covariates in predicting small mammal occupancy were understory vegetation cover, large snags, and treatment. Our analysis identified two generalist species found at relatively high occupancy rates across all sites, four open-forest species that responded positively to treatment, and two dense-forest species that responded negatively to treatment unless specific habitat features were retained. Our results indicate that all eight small mammal species can benefit from restoration treatments, particularly if aspects of their evolutionary environment (e.g., large trees, snags, woody debris) are restored. The occupancy modeling approach we used resulted in precise species-level estimates of occupancy in response to habitat attributes for a greater number of small mammal species than in other comparable studies. We recommend our approach for other studies faced with high variability and broad spatial and temporal scales in assessing impacts of treatments or habitat alteration on wildlife species. Moreover, since forest planning efforts are increasingly focusing on

  10. Integrating invasive grasses into carbon cycle projections: Cogongrass spread in southern pine forests

    Science.gov (United States)

    McCabe, T. D.; Flory, S. L.; Wiesner, S.; Dietze, M.

    2017-12-01

    Forested ecosystems are currently being disrupted by invasive species. One example is the invasive grass Imperata cylindrica (cogongrass), which is widespread in southeastern US pine forests. Pines forests dominate the forest cover of the southeast, and contribute to making the Southeast the United States' largest carbon sink. Cogongrass decreases the colonization of loblolly pine fine roots. If cogongrass continues to invade,this sink could be jeopardized. However, the effects of cogongrass invasion on carbon sequestration are largely unknown. We have projected the effects of elevated CO2 and changing climate on future cogongrass invasion. To test how pine stands are affected by cogongrass, cogongrass invasions were modeled using the Ecosystem Demography 2 (ED2) model, and parameterized using the Predictive Ecosystem Analyzer (PEcAn). ED2 takes into account local meteorological data, stand populations and succession, disturbance, and geochemical pools. PEcAn is a workflow that uses Bayesian sensitivity analyses and variance decomposition to quantify the uncertainty that each parameter contributes to overall model uncertainty. ED2 was run for four NEON and Ameriflux sites in the Southeast from the earliest available census of the site into 2010. These model results were compared to site measures to test for model accuracy and bias. To project the effect of elevated CO2 on cogongrass invasions, ED was run from 2006-2100 at four sites under four separate scenarios: 1) RPC4.5 CO2 and climate, 2) RPC4.5 climate only, with constant CO2 concentrations, 3) RPC4.5 Elevated CO2 only, with climate randomly selected from 2006-2026, 4) Present Day, made from randomly selected measures of CO2 and radiation from 2006-2026. Each scenario was run three times; once with cogongrass absent, once with a low cogongrass abundance, and once with a high cogongrass abundance. Model results suggest that many relevant parameters have high uncertainty due to lack of measurement. Further field

  11. Importance of Coarse Woody Debris to Avian Communities in Loblolly Pine Forests

    Energy Technology Data Exchange (ETDEWEB)

    Lohr, S.M.; Gauthreaux, S.A.; Kilgo, J.C.

    2001-06-14

    Investigates the importance of standing and down coarse woody debris to bird communities in loblolly pine forests, researchers compared breeding and nonbreeding responses of birds among two coarse woody debris removal and control treatments. Quantification of vegetation layers to determine their effects on the experimental outcome coarse woody debris removal had no effect on the nonbreeding bird community. Most breeding and nonbreeding species used habitats with sparse midstory and well-developed understory, where as sparse canopy cover and dense midstory were important to some nonbreeding species. Snag and down coarse woody debris practices that maintain a dense understory, sparse midstory and canopy will create favorable breeding habitat.

  12. Application of minidisk infiltrometer to estimate water repellency in Mediterranean pine forest soils

    Directory of Open Access Journals (Sweden)

    Alagna Vincenzo

    2017-09-01

    Full Text Available Assessment of soil water repellency (SWR was conducted in the decomposed organic floor layer (duff and in the mineral soil layer of two Mediterranean pine forests, one in Italy and the other in Spain, by the widely-used water drop penetration time (WDPT test and alternative indices derived from infiltration experiments carried out by the minidisk infiltrometer (MDI. In particular, the repellency index (RI was calculated as the adjusted ratio between ethanol and water soil sorptivities whereas the water repellency cessation time (WRCT and the specifically proposed modified repellency index (RIm were derived from the hydrophobic and wettable stages of a single water infiltration experiment. Time evolution of SWR and vegetation cover influence was also investigated at the Italian site. All indices unanimously detected severe SWR conditions in the duff of the pine forests. The mineral subsoils in the two forests showed different wettability and the clay-loam subsoil at Ciavolo forest was hydrophobic even if characterized by organic matter (OM content similar to the wettable soil of an adjacent glade. It was therefore assumed that the composition rather than the total amount of OM influenced SWR. The hydraulic conductivity of the duff differed by a factor of 3.8–5.8 between the two forested sites thus influencing the vertical extent of SWR. Indeed, the mineral subsoil of Javea showed wettable or weak hydrophobic conditions probably because leaching of hydrophobic compounds was slowed or prevented at all. Estimations of SWR according to the different indices were in general agreement even if some discrepancies were observed. In particular, at low hydrophobicity levels the SWR indices gathered from the MDI tests were able to signal sub-critical SWR conditions that were not detected by the traditional WDPT index. The WRCT and modified repellency index RIm yielded SWR estimates in reasonable agreement with those obtained with the more cumbersome RI

  13. Spatiotemporal Dynamics of Fire in Whitebark Pine Stands on two Mountains in the Lolo National Forest, Montana, USA.

    Science.gov (United States)

    Larson, E. R.; Grissino-Mayer, H. D.

    2004-12-01

    Whitebark pine (Pinus albicaulis) is a long-lived tree species that exists throughout high elevation and treeline forest communities of western North America. It is the foundation of a diminishing ecosystem that supports Clark's nutcrackers (Nucifraga columbiana), red squirrels (Tamiasciurus hudsonicus), grizzly bears (Ursus arctos), and black bears (U. americana). Several factors are directly linked to the decline of the whitebark pine ecosystem: mortality from recent and widespread mountain pine beetle (Dendroctonus ponderosae) outbreaks, infestation by the invasive white pine blister rust (Cronartium ribicola, an exotic fungal canker that weakens and eventually kills white pines), and fire suppression that may have altered the historic fire regime and enabled fire-intolerant tree species to encroach upon whitebark pine stands. The synergistic effects of these factors have led to a dramatic decline in whitebark pine communities throughout its native range, and in response land managers and conservationists have called for research to better understand the ecological dynamics of this little studied ecosystem. My research uses dendrochronology to investigate the fire history of whitebark pine stands on three mountains in the Lolo National Forest, Montana, via fire-scar and age structure analyses. I present here the results from the fire-scar analyses from Morrell Mountain where I obtained 40 cross sections from dead and down whitebark pines. Individual tree mean fire return intervals (MFRI) range from 33 to 119 years, with a stand MFRI of 49 years that includes fire scars dating to the 16th century. Fire events scarred multiple trees in AD 1754, 1796, and 1843, indicating a mixed-severity fire regime. The majority of the samples recorded a frost event in AD 1601, perhaps evidence of the AD 1600 eruption of Mt. Huaynapatina in the Peruvian Andes. My research not only provides an historical framework for land managers, but also provides an opportunity to examine long

  14. A climate response function explaining most of the variation in the forest floor needle mass and the needle decomposition in pine forests across Europe

    DEFF Research Database (Denmark)

    Kurz-Besson, C.; Coûteaux, M.M.; Berg, Bjørn

    2006-01-01

    The forest floor needle mass and the decomposition rates of pine needle litter in a European climate transect were studied in order to estimate the impact of climate change on forest soil carbon sequestration. Eight pine forests preserved from fire were selected along a climatic latitudinal...... gradient from 40° to 60° N, from Spain and Portugal to Sweden. The forest floor (Oi and Oe layers) was sorted into five categories of increasing decomposition level according to morphological criteria. The needle mass loss in each category was determined using a linear mass density method. The needle...... and a recalcitrant one. NF was correlated with actual evapotranspiration (AET) whereas the decomposition parameters (decomposition rate of the decomposable fraction, first year mass loss, forest floor needle mass, age of the most-decomposed category) were related to a combined response function to climate (CRF...

  15. Effects of artificial defoliation of pines on the structure and physiology of the soil fungal community of a mixed pine-spruce forest

    Science.gov (United States)

    Cullings, Ken; Raleigh, Christopher; New, Michael H.; Henson, Joan

    2005-01-01

    Loss of photosynthetic area can affect soil microbial communities by altering the availability of fixed carbon. We used denaturing gradient gel electrophoresis (DGGE) and Biolog filamentous-fungus plates to determine the effects of artificial defoliation of pines in a mixed pine-spruce forest on the composition of the fungal community in a forest soil. As measured by DGGE, two fungal species were affected significantly by the defoliation of pines (P soil fungus increased. The decrease in the amount of Cenococcum organisms may have occurred because of the formation of extensive hyphal networks by species of this genus, which require more of the carbon fixed by their host, or because this fungus is dependent upon quantitative differences in spruce root exudates. The defoliation of pines did not affect the overall composition of the soil fungal community or fungal-species richness (number of species per core). Biolog filamentous-fungus plate assays indicated a significant increase (P soil fungi and the rate at which these substrates were used, which could indicate an increase in fungal-species richness. Thus, either small changes in the soil fungal community give rise to significant increases in physiological capabilities or PCR bias limits the reliability of the DGGE results. These data indicate that combined genetic and physiological assessments of the soil fungal community are needed to accurately assess the effect of disturbance on indigenous microbial systems.

  16. Limited growth recovery after drought-induced forest dieback in very defoliated trees of two pine species

    Directory of Open Access Journals (Sweden)

    Guillermo eGuada

    2016-04-01

    Full Text Available Mediterranean pine forests display high resilience after extreme climatic events such as severe droughts. However, recent dry spells causing growth decline and triggering forest dieback challenge the capacity of some forests to recover following major disturbances. To describe how resilient the responses of forests to drought can be, we quantified growth dynamics in plantations of two pine species (Scots pine, black pine located in south-eastern Spain and showing drought-triggered dieback. Radial growth was characterized at inter- (tree-ring width and intra-annual (xylogenesis scales in three defoliation levels. It was assumed that the higher defoliation the more negative the impact of drought on tree growth. Tree-ring width chronologies were built and xylogenesis was characterized three years after the last severe drought occurred. Annual growth data and the number of tracheids produced in different stages of xylem formation were related to climate data at several time scales. Drought negatively impacted growth of the most defoliated trees in both pine species. In Scots pine, xylem formation started earlier in the non-defoliated than in the most defoliated trees. Defoliated trees presented the shortest duration of the radial-enlargement phase in both species. On average the most defoliated trees formed 60% of the number of mature tracheids formed by the non-defoliated trees in both species. Since radial enlargement is the xylogenesis phase most tightly related to final growth, this explains why the most defoliated trees grew the least due to their altered xylogenesis phases. Our findings indicate a very limited resilience capacity of drought-defoliated Scots and black pines. Moreover, droughts produce legacy effects on xylogenesis of highly defoliated trees which could not recover previous growth rates and are thus more prone to die.

  17. Historic Frequency and Severity of Fire in Whitebark Pine Forests of the Cascade Mountain Range, USA

    Directory of Open Access Journals (Sweden)

    Michael P. Murray

    2018-02-01

    Full Text Available Whitebark pine (Pinus albicaulis Engelm. is a foundation species of high elevation forest ecosystems in the Cascade Mountain Range of Oregon, Washington, and British Columbia. We examined fire evidence on 55 fire history sites located in the Cascade Range. To estimate dates of historic fires we analyzed 57 partial cross-sections from fire-scarred trees plus 700 increment cores. The resulting 101 fire events indicate fire has been a widespread component of Cascadian whitebark pine stands. Results are site specific and vary considerably. Whitebark pine stands appear to burn in a variety of severities and frequencies. Sites where fire intervals were detected ranged from 9 to 314 years, with a median of 49 years, and averaging 67 years. Fire intervals shortened significantly with higher latitudes. In assessing the most recent fire event at each site, overall, 56 percent burned as stand replacing events. In the 20th century, the number of fires diminished significantly. Due to conservation imperatives, re-introducing fire should be undertaken with extreme care to avoid substantial mortality of this endangered species.

  18. Net Ecosystem Fluxes of Hydrocarbons from a Ponderosa Pine Forest in Colorado

    Science.gov (United States)

    Rhew, R. C.; Turnipseed, A. A.; Ortega, J. V.; Smith, J. N.; Guenther, A. B.; Shen, S.; Martinez, L.; Koss, A.; Warneke, C.; De Gouw, J. A.; Deventer, M. J.

    2015-12-01

    Light (C2-C4) alkenes, light alkanes and isoprene (C5H8) are non-methane hydrocarbons that play important roles in the photochemical production of tropospheric ozone and in the formation of secondary organic aerosols. Natural terrestrial fluxes of the light hydrocarbons are poorly characterized, with global emission estimates based on limited field measurements. In 2014, net fluxes of these compounds were measured at the Manitou Experimental Forest Observatory, a semi-arid ponderosa pine forest in the Colorado Rocky Mountains and site of the prior BEACHON campaigns. Three field intensives were conducted between June 17 and August 10, 2014. Net ecosystem flux measurements utilized a relaxed eddy accumulation system coupled to an automated gas chromatograph. Summertime average emissions of ethene and propene were up to 90% larger than those observed from a temperate deciduous forest. Ethene and propene fluxes were also correlated to each other, similar to the deciduous forest study. Emissions of isoprene were small, as expected for a coniferous forest, and these fluxes were not correlated with either ethene or propene. Unexpected emissions of light alkanes were also observed, and these showed a distinct diurnal cycle. Understory flux measurements allowed for the partitioning of fluxes between the surface and the canopy. Full results from the three field intensives will be compared with environmental variables in order to parameterize the fluxes for use in modeling emissions.

  19. Collaborative restoration effects on forest structure in ponderosa pine-dominated forests of Colorado

    Science.gov (United States)

    Jeffery B. Cannon; Kevin J. Barrett; Benjamin M. Gannon; Robert N. Addington; Mike A. Battaglia; Paula J. Fornwalt; Gregory H. Aplet; Antony S. Cheng; Jeffrey L. Underhill; Jennifer S. Briggs; Peter M. Brown

    2018-01-01

    In response to large, severe wildfires in historically fire-adapted forests in the western US, policy initiatives, such as the USDA Forest Service’s Collaborative Forest Landscape Restoration Program (CFLRP), seek to increase the pace and scale of ecological restoration. One required component of this program is collaborative adaptive management, in which monitoring...

  20. Forest structure and plant diversity in maritime pine (Pinus pinaster Ait.) stands in central Spain

    Energy Technology Data Exchange (ETDEWEB)

    Osorio, L. F.; Bravo, F.; Zaldivar, P.; Pando, V.

    2009-07-01

    The relationship between forest structure and plant diversity in Mediterranean Maritime pine stands (Pinus pinaster Ait.) in the Iberian Range (Spain) was studied. Forty eight stands were sampled. In each, a circular plot (15 m radius) and a transect (25*1 m{sup 2}) were established to estimate stand variables and record presence and abundance of vascular species respectively. Canonical correlation analysis (CCA), simple correlations and multiple stepwise linear regressions were used to explore the relationship between plant diversity and forest structure. Correlation between diversity measurements and stand variables is very weak, but significant correlations were found when evaluating each set of variables separately. Presence and cover of some species (for instance, Veronica arvensis L. or Micropyrum tenellum (L.) Link) is correlated with stand variables; however, determination coefficients found in step-by-step regression are not significant. (Author) 34 refs.

  1. Emissions of BVOC from lodgepole pine in response to mountain pine beetle attack in high and low mortality forest stands

    Directory of Open Access Journals (Sweden)

    T. R. Duhl

    2013-01-01

    Full Text Available In this screening study, biogenic volatile organic compound (BVOC emissions from intact branches of lodgepole pine (Pinus contorta trees were measured from trees at two forested sites that have been impacted differently by the mountain pine beetle (MPB, with one having higher mortality and the other with lower mortality. Differences in the amounts and chemical diversity of BVOC between the two sites and from apparently healthy trees versus trees in different stages of MPB attack are presented, as well as (for one site observed seasonal variability in emissions. A brief comparison is made of geological and climatic characteristics as well as prior disturbances (both natural and man-made at each site. Trees sampled at the site experiencing high MPB-related tree mortality had lower chemodiversity in terms of monoterpene (MT emission profiles, while profiles were more diverse at the lower-mortality site. Also at the higher-mortality site, MPB-infested trees in various stages of decline had lower emissions of sesquiterpenes (SQTs compared to healthy trees, while at the site with lower mortality, MPB-survivors had significantly higher SQT emissions during part of the growing season when compared to both uninfested and newly infested trees. SQT profiles differed between the two sites and, like monoterpene and oxygenated VOC profiles, varied through the season. For the low-mortality site in which repeated measurements were made over the course of the early summer–late fall, higher chemical diversity was observed in early- compared to late-season measurements for all compound classes investigated (MT, oxygenated VOC, and SQT, with the amount of change appearing to correlate to the MPB status of the trees studied. Emissions of 2-methyl-3-buten-2-ol (MBO had a distinct seasonal signal but were not much different between healthy or infested trees, except in trees with dead needles, from which emissions of this compound were negligible, and in late

  2. Transpiration and CO2 fluxes of a pine forest: modelling the undergrowth effect

    Directory of Open Access Journals (Sweden)

    V. Rivalland

    2005-02-01

    Full Text Available A modelling study is performed in order to quantify the relative effect of allowing for the physiological properties of an undergrowth grass sward on total canopy water and carbon fluxes of the Le-Bray forest (Les-Landes, South-western France. The Le-Bray forest consists of maritime pine and an herbaceous undergrowth (purple moor-grass, which is characterised by a low stomatal control of transpiration, in contrast to maritime pine. A CO2-responsive land surface model is used that includes responses of woody and herbaceous species to water stress. An attempt is made to represent the properties of the undergrowth vegetation in the land surface model Interactions between Soil, Biosphere, and Atmosphere, CO2-responsive, ISBA-A-gs. The new adjustment allows for a fairly different environmental response between the forest canopy and the understory in a simple manner. The model's simulations are compared with long term (1997 and 1998 micro-meteorological measurements over the Le-Bray site. The fluxes of energy, water and CO2, are simulated with and without the improved representation of the undergrowth vegetation, and the two simulations are compared with the observations. Accounting for the undergrowth permits one to improve the model's scores. A simple sensitivity experiment shows the behaviour of the model in response to climate change conditions, and the understory effect on the water balance and carbon storage of the forest. Accounting for the distinct characteristics of the undergrowth has a substantial and positive effect on the model accuracy and leads to a different response to climate change scenarios.

  3. Interaction of an invasive bark beetle with a native forest pathogen: Potential effect of dwarf mistletoe on range expansion of mountain pine beetle in jack pine forests

    Science.gov (United States)

    Jennifer Klutsch; Nadir Erbilgin

    2012-01-01

    In recent decades, climate change has facilitated shifts in species ranges that have the potential to significantly affect ecosystem dynamics and resilience. Mountain pine beetle (Dendroctonus ponderosae) is expanding east from British Columbia, where it has killed millions of pine trees, primarily lodgepole pine (Pinus contorta...

  4. Modelling water and {sup 36}Cl cycling in a Belgian pine forest - Model for {sup 36}Cl cycling in a Belgian pine forest

    Energy Technology Data Exchange (ETDEWEB)

    Vives i Batlle, Jordi; Vandenhove, Hildegarde; Gielen, Sienke [Belgian Nuclear Research Centre, Boeretang 200, 2400 Mol (Belgium)

    2014-07-01

    A simplified, 1-D soil-groundwater-vegetation model to represent the cycling of water and of {sup 36}Cl in a Belgian Scots pine forest is presented and discussed. The model contains a soil column with layers of different (but uniform) field capacity and soil porosity, which are penetrated by tree roots. Flow through porous media is assumed to circulate according to Darcy and Philips laws, using empirical soil hydraulic properties without recourse to Richards' equation. The vegetation is represented by means of a compartment model including simplified representation of sap flow, translocation and litterfall in relation to different parts of the tree. The water table height is variable according to the balance between precipitation, capillary rise, solar radiation, plant uptake and evapotranspiration. The influence of local fluvial sources of water can also be evaluated in a simplified way as a losing/gaining stream input to the soil column. Time dependent data on temperature, solar irradiation, rainfall, crop coefficient and leaf area index (LAI) are used as input to the model in order to calculate evapotranspiration and a simplified approach to foliar interception. The chlorine flux follows the water flux in both soil and the trees, using retardation in soil and experimentally measured translocation factors within the plant. The chlorine flux is optimised and validated with recourse to a previous {sup 36}Cl compartment model. Although considered to be a relatively simple model, initial results suggest a reasonable consistency between previously published water balance and field measurements in a Scots pine stand from the vicinity of Mol, Belgium. The mean soil water content is predicted to be around 25%, the plant water is stored in the order roots > plant above roots > leaf surfaces, water table height below ground fluctuates between 2.1 and 2.6 m compared with a measured water table height of 1.8 - 20 m and pine transpiration is less than 1.2 mm/d compared

  5. Climate Drives Episodic Conifer Establishment after Fire in Dry Ponderosa Pine Forests of the Colorado Front Range, USA

    Directory of Open Access Journals (Sweden)

    Monica T. Rother

    2017-05-01

    Full Text Available In recent years, warming climate and increased fire activity have raised concern about post-fire recovery of western U.S. forests. We assessed relationships between climate variability and tree establishment after fire in dry ponderosa pine forests of the Colorado Front Range. We harvested and aged over 400 post-fire juvenile ponderosa pine (Pinus ponderosa and Douglas-fir (Pseudotsuga menziesii trees using an improved tree-ring based approach that yielded annually-resolved dates and then assessed relationships between climate variability and pulses of tree establishment. We found that tree establishment was largely concentrated in years of above-average moisture availability in the growing season, including higher amounts of precipitation and more positive values of the Palmer Drought Severity Index. Under continued climate change, drier conditions associated with warming temperatures may limit forest recovery after fire, which could result in lower stand densities or shifts to non-forested vegetation in some areas.

  6. Content of chemical elements in tree rings of lodgepole pine and whitebark pine from a subalpine Sierra Nevada forest

    Science.gov (United States)

    David L. Peterson; Darren R. Anderson

    1990-01-01

    The wood of lodgepole pines and whitebark pines from a high elevation site in the east central Sierra Nevada of California was analyzed for chemical content to determine whether there were any temporal patterns of chemical distribution in tree rings. Cores were taken from 10 trees of each species and divided into 5-year increments for chemical analysis. Correlation...

  7. Effects of Thinning Intensities on Soil Infiltration and Water Storage Capacity in a Chinese Pine-Oak Mixed Forest

    OpenAIRE

    Chen, Lili; Yuan, Zhiyou; Shao, Hongbo; Wang, Dexiang; Mu, Xingmin

    2014-01-01

    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning):

  8. Non-indigenous plant species and their ecological range in Central European pine (Pinus sylvestris L.) forests

    OpenAIRE

    Zerbe , Stefan; Wirth , Petra

    2006-01-01

    International audience; In this study, forest ecosystems were analysed with regard to the occurrence and ecological range of non-indigenous plant species. Pine forests in the NE German lowland, which naturally and anthropogenically occur on a broad range of different sites, were taken as an example. The analysis is based on a data set of about 2 300 vegetation plots. The ecological range was assessed applying Ellenberg's ecological indicator values. Out of a total of 362 taxa recorded in the ...

  9. Rapid Turnover and Minimal Accretion of Mineral Soil Carbon During 60-Years of Pine Forest Growth on Previously Cultivated Land

    Science.gov (United States)

    Richter, D., Jr.; Mobley, M. L.; Billings, S. A.; Markewitz, D.

    2016-12-01

    At the Calhoun Long-Term Soil-Ecosystem field experiment (1957-present), reforestation of previously cultivated land over fifty years nearly doubled soil organic carbon (SOC) in surface soils (0 to 7.5-cm) but these gains were offset by significant SOC losses in subsoils (35 to 60-cm). Nearly all of the accretions in surface soils amounted to gains in light fraction SOC, whereas losses at depth were associated with silt and clay-sized particles. These changes are documented in the Calhoun Long-Term Soil-Ecosystem (LTSE) study that resampled soil from 16 plots about every five years and archived all soil samples from four soil layers within the upper 60-cm of mineral soil. We combined soil bulk density, density fractionation, stable isotopes, and radioisotopes to explore changes in SOC and soil organic nitrogen (SON) associated with five decades of the growth of a loblolly pine secondary forest. Isotopic signatures showed relatively large accumulations of contemporary forest-derived carbon in surface soils, and no accumulation of forest-derived carbon in subsoils. We interpret results to indicate that land-use change from cotton fields to secondary pine forests drove soil biogeochemical and hydrological changes that enhanced root and microbial activity and SOM decomposition in subsoils. As pine stands matured and are now transitioning to mixed pines and hardwoods, demands on soil organic matter for nutrients to support aboveground growth has eased due to pine mortality, and bulk SOM and SON and their isotopes in subsoils have stabilized. We anticipate major changes in the next fifty years as 1957 pine trees transition to hardwoods. This study emphasizes the importance of long-term experiments and deep soil measurements when characterizing SOC and SON responses to land use change. There is a remarkable paucity of E long-term soil data deeper than 30 cm.

  10. Influence of climate and land use on historical surface fires in pine-oak forests, Sierra Madre Occidental, Mexico

    Science.gov (United States)

    Emily K. Heyerdahl; Ernesto Alvarado

    2003-01-01

    The rugged mountains of the Sierra Madre Occidental, in north-central Mexico, support a mosaic of diverse ecosystems. Of these, the high-elevation, temperate pine-oak forests are ecologically significant for their extensiveness and biodiversity. They cover nearly half the land area in the states of Durango and Chihuahua (42%), and comprise a similar percentage of the...

  11. Presence of Nitrosospiral cluster 2 bacteria corresponds to N transformation rates in nine acid Scots pine forest soils.

    NARCIS (Netherlands)

    Nugroho, R. Adi; Roling, W.F.M.; Laverman, A.M.; Zoomer, R.; Verhoef, H.A.

    2005-01-01

    The relation between environmental factors and the presence of ammonia-oxidising bacteria (AOB), and its consequences for the N transformation rates were investigated in nine Scots pine (Pinus sylvestris L.) forest soils. In general, the diversity in AOB appears to be strikingly low compared to

  12. Stratification and seasonal stability of diverse bacterial communities in a Pinus merkusii (pine) forest soil in central Java, Indonesia.

    NARCIS (Netherlands)

    Krave, A.S.; Lin, B.; Braster, M.; Laverman, A.M.; van Straalen, N.M.; Roling, W.F.M.; van Verseveld, H.W.

    2002-01-01

    In Java, Indonesia, many nutrient-poor soils are intensively reforested with Pinus merkusii (pine). Information on nutrient cycles and microorganisms involved in these cycles will benefit the management of these important forests. Here, seasonal effects on the stratification of bacterial community

  13. Hydrologic effects of size and location of harvesting on a large drained pine forest on organic soils

    Science.gov (United States)

    Devendra M. Amatya; Kim Hyunwoo; George M. Chescheir; R. Wayne Nettles Skaggs

    2008-01-01

    A calibrated DRAINWAT model was used to evaluate long -term hydrologic effects of conversion to agriculture of a 30 km2 pine forest on mostly organic soils in North Carolina, USA. Fifty years of weather data were used for determining baseline outflows. Simulation revealed that increased mean annual outflow was significant only for a 75% conversion at both upstream and...

  14. Influence of elevation on bark beetle (Coleoptera: Curculionidae, Scolytinae) community structure and flight periodicity in ponderosa pine forests of Arizona

    Science.gov (United States)

    Kelly K. Williams; Joel D. McMillin; Tom E. DeGomez; Karen M. Clancy; Andy Miller

    2008-01-01

    We examined abundance and flight periodicity of five Ips and six Dendroctonus species (Coleoptera: Curculionidae, Scolytinae) among three different elevation bands in ponderosa pine (Pinus ponderosa Douglas ex. Lawson) forests of northcentral Arizona. Bark beetle populations were monitored at 10 sites in each of three elevation...

  15. Effects of low intensity prescribed fires on ponderosa pine forests in wilderness areas of Zion National Park, Utah

    Science.gov (United States)

    Henry V. Bastian

    2001-01-01

    Vegetation and fuel loading plots were monitored and sampled in wilderness areas treated with prescribed fire. Changes in ponderosa pine (Pinus ponderosa) forest structure tree species and fuel loading are presented. Plots were randomly stratified and established in burn units in 1995. Preliminary analysis of nine plots 2 years after burning show litter was reduced 54....

  16. Chemical composition of needles and cambial activity of stems of Scots pine trees affected by air pollutants in Polish forests

    Science.gov (United States)

    Wojciech Dmuchowski; Ewa U. Kurczynska; Wieslaw Wloch

    1998-01-01

    The impact of environmental pollution is defined for the chemical composition of Scots pine (Pinus sylvestris L.) needles and cambial activity in the tree stems in Polish forests. The research investigated 20-year-old trees growing in two areas in significantly different levels of pollution. The highly polluted area was located near the Warsaw...

  17. Dynamics and stratification of functional groups of micro- and mesoarthropods in the organic layer of a Scots pine forest.

    NARCIS (Netherlands)

    Berg, M.P.; Kniese, J.P.; Bedaux, J.J.M.; Verhoef, H.A.

    1998-01-01

    This paper addresses the abundance, biomass and microstratification of functional groups of micro- and mesoarthropods inhabiting the organic layers of a Scots pine forest (Pinus sylvestris L.). An experiment using stratified litterbags, containing organic material of four degradation stages, i.e.,

  18. Interactive effects of historical logging and fire exclusion on ponderosa pine forest structure in the northern Rockies.

    Science.gov (United States)

    Naficy, Cameron; Sala, Anna; Keeling, Eric G; Graham, Jon; DeLuca, Thomas H

    2010-10-01

    Increased forest density resulting from decades of fire exclusion is often perceived as the leading cause of historically aberrant, severe, contemporary wildfires and insect outbreaks documented in some fire-prone forests of the western United States. Based on this notion, current U.S. forest policy directs managers to reduce stand density and restore historical conditions in fire-excluded forests to help minimize high-severity disturbances. Historical logging, however, has also caused widespread change in forest vegetation conditions, but its long-term effects on vegetation structure and composition have never been adequately quantified. We document that fire-excluded ponderosa pine forests of the northern Rocky Mountains logged prior to 1960 have much higher average stand density, greater homogeneity of stand structure, more standing dead trees and increased abundance of fire-intolerant trees than paired fire-excluded, unlogged counterparts. Notably, the magnitude of the interactive effect of fire exclusion and historical logging substantially exceeds the effects of fire exclusion alone. These differences suggest that historically logged sites are more prone to severe wildfires and insect outbreaks than unlogged, fire-excluded forests and should be considered a high priority for fuels reduction treatments. Furthermore, we propose that ponderosa pine forests with these distinct management histories likely require distinct restoration approaches. We also highlight potential long-term risks of mechanical stand manipulation in unlogged forests and emphasize the need for a long-term view of fuels management.

  19. Water and Energy Balances of Loblolly Pine Plantation Forests during a Full Stand Rotation

    Science.gov (United States)

    Sun, G.; Mitra, B.; Domec, J. C.; Gavazi, M.; Yang, Y.; Tian, S.; Zietlow, D.; McNulty, S.; King, J.; Noormets, A.

    2017-12-01

    partitioning of precipitation and solar energy in pine forests. In addition, we conclude that accessible groundwater was important factor for stabilizing forest water and energy balances during a drought in the lower coastal ecosystems.

  20. Carbon and water fluxes from ponderosa pine forests disturbed by wildfire and thinning.

    Science.gov (United States)

    Dore, S; Kolb, T E; Montes-Helu, M; Eckert, S E; Sullivan, B W; Hungate, B A; Kaye, J P; Hart, S C; Koch, G W; Finkral, A

    2010-04-01

    Disturbances alter ecosystem carbon dynamics, often by reducing carbon uptake and stocks. We compared the impact of two types of disturbances that represent the most likely future conditions of currently dense ponderosa pine forests of the southwestern United States: (1) high-intensity fire and (2) thinning, designed to reduce fire intensity. High-severity fire had a larger impact on ecosystem carbon uptake and storage than thinning. Total ecosystem carbon was 42% lower at the intensely burned site, 10 years after burning, than at the undisturbed site. Eddy covariance measurements over two years showed that the burned site was a net annual source of carbon to the atmosphere whereas the undisturbed site was a sink. Net primary production (NPP), evapotranspiration (ET), and water use efficiency were lower at the burned site than at the undisturbed site. In contrast, thinning decreased total ecosystem carbon by 18%, and changed the site from a carbon sink to a source in the first posttreatment year. Thinning also decreased ET, reduced the limitation of drought on carbon uptake during summer, and did not change water use efficiency. Both disturbances reduced ecosystem carbon uptake by decreasing gross primary production (55% by burning, 30% by thinning) more than total ecosystem respiration (TER; 33-47% by burning, 18% by thinning), and increased the contribution of soil carbon dioxide efflux to TER. The relationship between TER and temperature was not affected by either disturbance. Efforts to accurately estimate regional carbon budgets should consider impacts on carbon dynamics of both large disturbances, such as high-intensity fire, and the partial disturbance of thinning that is often used to prevent intense burning. Our results show that thinned forests of ponderosa pine in the southwestern United States are a desirable alternative to intensively burned forests to maintain carbon stocks and primary production.

  1. Patterns of biomass and carbon distribution across a chronosequence of Chinese pine (Pinus tabulaeformis) forests.

    Science.gov (United States)

    Zhao, Jinlong; Kang, Fengfeng; Wang, Luoxin; Yu, Xiaowen; Zhao, Weihong; Song, Xiaoshuai; Zhang, Yanlei; Chen, Feng; Sun, Yu; He, Tengfei; Han, Hairong

    2014-01-01

    Patterns of biomass and carbon (C) storage distribution across Chinese pine (Pinus tabulaeformis) natural secondary forests are poorly documented. The objectives of this study were to examine the biomass and C pools of the major ecosystem components in a replicated age sequence of P. tabulaeformis secondary forest stands in Northern China. Within each stand, biomass of above- and belowground tree, understory (shrub and herb), and forest floor were determined from plot-level investigation and destructive sampling. Allometric equations using the diameter at breast height (DBH) were developed to quantify plant biomass. C stocks in the tree and understory biomass, forest floor, and mineral soil (0-100 cm) were estimated by analyzing the C concentration of each component. The results showed that the tree biomass of P. tabulaeformis stands was ranged from 123.8 Mg·ha-1 for the young stand to 344.8 Mg·ha-1 for the mature stand. The understory biomass ranged from 1.8 Mg·ha-1 in the middle-aged stand to 3.5 Mg·ha-1 in the young stand. Forest floor biomass increased steady with stand age, ranging from 14.9 to 23.0 Mg·ha-1. The highest mean C concentration across the chronosequence was found in tree branch while the lowest mean C concentration was found in forest floor. The observed C stock of the aboveground tree, shrub, forest floor, and mineral soil increased with increasing stand age, whereas the herb C stock showed a decreasing trend with a sigmoid pattern. The C stock of forest ecosystem in young, middle-aged, immature, and mature stands were 178.1, 236.3, 297.7, and 359.8 Mg C ha-1, respectively, greater than those under similar aged P. tabulaeformis forests in China. These results are likely to be integrated into further forest management plans and generalized in other contexts to evaluate C stocks at the regional scale.

  2. Patterns of biomass and carbon distribution across a chronosequence of Chinese pine (Pinus tabulaeformis forests.

    Directory of Open Access Journals (Sweden)

    Jinlong Zhao

    Full Text Available Patterns of biomass and carbon (C storage distribution across Chinese pine (Pinus tabulaeformis natural secondary forests are poorly documented. The objectives of this study were to examine the biomass and C pools of the major ecosystem components in a replicated age sequence of P. tabulaeformis secondary forest stands in Northern China. Within each stand, biomass of above- and belowground tree, understory (shrub and herb, and forest floor were determined from plot-level investigation and destructive sampling. Allometric equations using the diameter at breast height (DBH were developed to quantify plant biomass. C stocks in the tree and understory biomass, forest floor, and mineral soil (0-100 cm were estimated by analyzing the C concentration of each component. The results showed that the tree biomass of P. tabulaeformis stands was ranged from 123.8 Mg·ha-1 for the young stand to 344.8 Mg·ha-1 for the mature stand. The understory biomass ranged from 1.8 Mg·ha-1 in the middle-aged stand to 3.5 Mg·ha-1 in the young stand. Forest floor biomass increased steady with stand age, ranging from 14.9 to 23.0 Mg·ha-1. The highest mean C concentration across the chronosequence was found in tree branch while the lowest mean C concentration was found in forest floor. The observed C stock of the aboveground tree, shrub, forest floor, and mineral soil increased with increasing stand age, whereas the herb C stock showed a decreasing trend with a sigmoid pattern. The C stock of forest ecosystem in young, middle-aged, immature, and mature stands were 178.1, 236.3, 297.7, and 359.8 Mg C ha-1, respectively, greater than those under similar aged P. tabulaeformis forests in China. These results are likely to be integrated into further forest management plans and generalized in other contexts to evaluate C stocks at the regional scale.

  3. Assisting the U.S. Forest Service in monitoring and managing the Pacific pine marten

    Science.gov (United States)

    Force, A.; Hadley, N.; Howell, B. L.; Holsinger, K.

    2017-12-01

    Innovative partnerships that bridge institutional sectors may be key in seizing many opportunities for highly effective projects. Adventure Scientists is a nonprofit organization that works in partnership with governments, universities, businesses and other nonprofits to support their need for actionable, research-grade data. In every partnership, it is critical that responsible decision-makers are involved and in place to use the data collected, such as to inform new resource management strategies or regulatory policies. In this presentation, we will highlight our experience working on one such partnership. In 2013, the U.S. Forest Service and Adventure Scientists collaborated on a two-year project to better understand Pacific pine marten (Martes caurina), a small native carnivore, in the Olympic National Forest. In response to the species' recent disappearance, Forest managers needed to gather more accurate data on martens' presence and abundance to support species management. Adventure Scientists was in a unique position to provide the agency this needed data-collection capacity. Volunteers collected data about the marten populations by positioning and monitoring camera traps throughout the area. Utilizing our volunteer-collected data, the U.S. Forest Service was able to inform the management and protection of these threatened species in U.S Forest Service Region 6. This project was also successful in establishing the foundation for an expanded, long-term relationship with the agency, where both parties continue to explore partnership opportunities for Adventure Scientists to collect data system-wide in support of U.S. Forest Service improved land management and policy decisions.

  4. Response of water use efficiency to summer drought in a boreal Scots pine forest in Finland

    Science.gov (United States)

    Gao, Yao; Markkanen, Tiina; Aurela, Mika; Mammarella, Ivan; Thum, Tea; Tsuruta, Aki; Yang, Huiyi; Aalto, Tuula

    2017-09-01

    The influence of drought on plant functioning has received considerable attention in recent years, however our understanding of the response of carbon and water coupling to drought in terrestrial ecosystems still needs to be improved. A severe soil moisture drought occurred in southern Finland in the late summer of 2006. In this study, we investigated the response of water use efficiency to summer drought in a boreal Scots pine forest (Pinus sylvestris) on the daily time scale mainly using eddy covariance flux data from the Hyytiälä (southern Finland) flux site. In addition, simulation results from the JSBACH land surface model were evaluated against the observed results. Based on observed data, the ecosystem level water use efficiency (EWUE; the ratio of gross primary production, GPP, to evapotranspiration, ET) showed a decrease during the severe soil moisture drought, while the inherent water use efficiency (IWUE; a quantity defined as EWUE multiplied with mean daytime vapour pressure deficit, VPD) increased and the underlying water use efficiency (uWUE, a metric based on IWUE and a simple stomatal model, is the ratio of GPP multiplied with a square root of VPD to ET) was unchanged during the drought. The decrease in EWUE was due to the stronger decline in GPP than in ET. The increase in IWUE was because of the decreased stomatal conductance under increased VPD. The unchanged uWUE indicates that the trade-off between carbon assimilation and transpiration of the boreal Scots pine forest was not disturbed by this drought event at the site. The JSBACH simulation showed declines of both GPP and ET under the severe soil moisture drought, but to a smaller extent compared to the observed GPP and ET. Simulated GPP and ET led to a smaller decrease in EWUE but a larger increase in IWUE because of the severe soil moisture drought in comparison to observations. As in the observations, the simulated uWUE showed no changes in the drought event. The model deficiencies exist

  5. Pine Plantations and Invasion Alter Fuel Structure and Potential Fire Behavior in a Patagonian Forest-Steppe Ecotone

    Directory of Open Access Journals (Sweden)

    Juan Paritsis

    2018-03-01

    Full Text Available Planted and invading non-native plant species can alter fire regimes through changes in fuel loads and in the structure and continuity of fuels, potentially modifying the flammability of native plant communities. Such changes are not easily predicted and deserve system-specific studies. In several regions of the southern hemisphere, exotic pines have been extensively planted in native treeless areas for forestry purposes and have subsequently invaded the native environments. However, studies evaluating alterations in flammability caused by pines in Patagonia are scarce. In the forest-steppe ecotone of northwestern Patagonia, we evaluated fine fuels structure and simulated fire behavior in the native shrubby steppe, pine plantations, pine invasions, and mechanically removed invasions to establish the relative ecological vulnerability of these forestry and invasion scenarios to fire. We found that pine plantations and their subsequent invasion in the Patagonian shrubby steppe produced sharp changes in fine fuel amount and its vertical and horizontal continuity. These changes in fuel properties have the potential to affect fire behavior, increasing fire intensity by almost 30 times. Pruning of basal branches in plantations may substantially reduce fire hazard by lowering the probability of fire crowning, and mechanical removal of invasion seems effective in restoring original fuel structure in the native community. The current expansion of pine plantations and subsequent invasions acting synergistically with climate warming and increased human ignitions warrant a highly vulnerable landscape in the near future for northwestern Patagonia if no management actions are undertaken.

  6. Frequent Prescribed Burning as a Long-term Practice in Longleaf Pine Forests Does Not Affect Detrital Chemical Composition.

    Science.gov (United States)

    Coates, T Adam; Chow, Alex T; Hagan, Donald L; Wang, G Geoff; Bridges, William C; Dozier, James H

    2017-09-01

    The O horizon, or detrital layer, of forest soils is linked to long-term forest productivity and health. Fuel reduction techniques, such as prescribed fire, can alter the thickness and composition of this essential ecosystem component. Developing an understanding of the changes in the chemical composition of forest detritus due to prescribed fire is essential for forest managers and stakeholders seeking sustainable, resilient, and productive ecosystems. In this study, we evaluated fuel quantity, fuel structure, and detrital chemical composition in longleaf pine ( Miller) forests that have been frequently burned for the last 40 yr at the Tom Yawkey Wildlife Center in Georgetown, SC. Our results suggest that frequent prescribed fire reduces forest fuel quantity ( burned detritus. Our burning activities varied in the short term, consisting of annual dormant, annual growing, and biennial dormant season burns. Seasonal distinctions were present for fuel quantity and vertical fuel structure, but these differences were not noted for the benzene/phenol ratio. These results are significant as more managers consider burning existing longleaf stands while determining effective management practices for longleaf stands yet to be established. Managers of such stands can be confident that frequent, low-intensity, low-severity prescribed burns in longleaf pine forests do little to affect the long-term chemical composition of forest detritus. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  7. A review of precipitation and temperature control on seedling emergence and establishment for ponderosa and lodgepole pine forest regeneration

    Science.gov (United States)

    Petrie, Matthew; Wildeman, A.M.; Bradford, John B.; Hubbard, R.M.; Lauenroth, W.K.

    2016-01-01

    The persistence of ponderosa pine and lodgepole pine forests in the 21st century depends to a large extent on how seedling emergence and establishment are influenced by driving climate and environmental variables, which largely govern forest regeneration. We surveyed the literature, and identified 96 publications that reported data on dependent variables of seedling emergence and/or establishment and one or more independent variables of air temperature, soil temperature, precipitation and moisture availability. Our review suggests that seedling emergence and establishment for both species is highest at intermediate temperatures (20 to 25 °C), and higher precipitation and higher moisture availability support a higher percentage of seedling emergence and establishment at daily, monthly and annual timescales. We found that ponderosa pine seedlings may be more sensitive to temperature fluctuations whereas lodgepole pine seedlings may be more sensitive to moisture fluctuations. In a changing climate, increasing temperatures and declining moisture availability may hinder forest persistence by limiting seedling processes. Yet, only 23 studies in our review investigated the effects of driving climate and environmental variables directly. Furthermore, 74 studies occurred in a laboratory or greenhouse, which do not often replicate the conditions experienced by tree seedlings in a field setting. It is therefore difficult to provide strong conclusions on how sensitive emergence and establishment in ponderosa and lodgepole pine are to these specific driving variables, or to investigate their potential aggregate effects. Thus, the effects of many driving variables on seedling processes remain largely inconclusive. Our review stresses the need for additional field and laboratory studies to better elucidate the effects of driving climate and environmental variables on seedling emergence and establishment for ponderosa and lodgepole pine.

  8. Ecological consequences of mountain pine beetle outbreaks for wildlife in western North American forests

    Science.gov (United States)

    Saab, Victoria A.; Latif, Quresh S.; Rowland, Mary M.; Johnson, Tracey N.; Chalfoun, Anna D.; Buskirk, Steven W.; Heyward, Joslin E.; Dresser, Matthew A.

    2014-01-01

    Mountain pine beetle (Dendroctonus ponderosae) (MPB) outbreaks are increasingly prevalent in western North America, causing considerable ecological change in pine (Pinus spp.) forests with important implications for wildlife. We reviewed studies examining wildlife responses to MPB outbreaks and postoutbreak salvage logging to inform forest management and guide future research. Our review included 16 studies describing MPB outbreak relationships with 89 bird species and 6 studies describing relationships with 11 mammalian species, but no studies of reptiles or amphibians. We included studies that compared wildlife response metrics temporally (before versus after the outbreak) and spatially (across sites that varied in severity of outbreak) in relation to beetle outbreaks. Outbreaks ranged in size from 20,600 to ≥107 ha and studies occurred 1‐30 years after the peak MPB outbreak, but most studies were conducted over the short-term (i.e., ≤6 years after the peak of MPB-induced tree mortality). Birds were the only taxa studied frequently; however, high variability existed among those studies to allow many inferences, although some patterns were evident. Avian studies concluded that cavity-nesting species responded more favorably to beetle-killed forests than species with open-cup nests, and species nesting in the shrub layer favored outbreak forests compared with ground and open-cup canopy nesters that generally showed mixed relationships. Bark-drilling species as a group clearly demonstrated a positive short-term association with MPB epidemics compared with that of other foraging assemblages. Cavity-nesting birds that do not consume bark beetles (i.e., secondary cavity-nesting species and nonbark-drilling woodpeckers) also exhibited some positive responses to MPB outbreaks, although not as pronounced or consistent as those of bark-drilling woodpeckers. Mammalian responses to MPB outbreaks were mixed. Studies consistently reported negative effects of MPB

  9. Ecosystem Nitrogen Retention Following Severe Bark Beetle and Salvage Logging Disturbance in Lodgepole Pine Forests: a 15N Enrichment Study

    Science.gov (United States)

    Avera, B.; Rhoades, C.; Paul, E. A.; Cotrufo, M. F.

    2017-12-01

    In recent decades, bark beetle outbreaks have caused high levels of tree mortality in lodgepole pine (Pinus contorta) dominated forests across western North America. Previous work has found increased soil mineral nitrogen (N) with tree mortality in beetle infested stands, but surprisingly little change in stream N export. These findings suggest an important role of residual live vegetation and altered soil microbial response for retaining surplus N and mitigating N losses from disturbed lodgepole forests. Post outbreak salvage of merchantable timber reduces fuel levels and promotes tree regeneration; however, the implications of the combined bark beetle and harvesting disturbances on ecosystem N retention and productivity are uncertain. To advance understanding of post-disturbance N retention we compare unlogged beetle-infested forests and salvage logged stands with post-harvest woody residue retention or removal. We applied 15N-labeled (2 atom%) and natural abundance ammonium sulfate to eight year old lodgepole pine seedlings in three replicate plots of the three forest management treatments. This approach allows us to quantify the relative contributions of N retention in soil, microbial biomass, and plant tissue. Our study targets gaps in understanding of the processes that regulate N utilization and transfer between soil and vegetation that result in effective N retention in lodgepole pine ecosystems. These findings will also help guide forest harvest and woody residue management practices in order to maintain soil productivity.

  10. Overstory tree status following thinning and burning treatments in mixed pine-hardwood stands on the William B. Bankhead National Forest, Alabama

    Science.gov (United States)

    Callie Jo Schweitzer; Yong Wang

    2013-01-01

    Prescribed burning and thinning are intermediate stand treatments whose consequences when applied in mixed pine-hardwood stands are unknown. The William B. Bankhead National Forest in northcentral Alabama has undertaken these two options to move unmanaged, 20- to 50-year-old loblolly pine (Pinus taeda L.) plantations towards upland hardwood-dominated...

  11. First report of Fusarium proliferatum causing Fusarium root disease on sugar pine (Pinus lambertiana) in a forest container nursery in California

    Science.gov (United States)

    J. E. Stewart; K. Otto; G. A. Cline; Kas Dumroese; Ned Klopfenstein; M. -S. Kim

    2016-01-01

    Fusarium species, specifically F. commune, F. proliferatum, and F. solani, can cause severe damping-off and root disease in container and bareroot forest nurseries throughout North America. Many conifer and hardwood species can be affected, but Douglas-fir (Pseudotsuga menziesii), western white pine (Pinus monticola), and ponderosa pine (P. ponderosa) are known to be...

  12. Short-term ecological consequences of collaborative restoration treatments in ponderosa pine forests of Colorado

    Science.gov (United States)

    Briggs, Jenny S.; Fornwalt, Paula J.; Feinstein, Jonas A.

    2017-01-01

    Ecological restoration treatments are being implemented at an increasing rate in ponderosa pine and other dry conifer forests across the western United States, via the USDA Forest Service’s Collaborative Forest Landscape Restoration (CFLR) program. In this program, collaborative stakeholder groups work with National Forests (NFs) to adaptively implement and monitor ecological restoration treatments intended to offset the effects of many decades of anthropogenic stressors. We initiated a novel study to expand the scope of treatment effectiveness monitoring efforts in one of the first CFLR landscapes, Colorado’s Front Range. We used a Before/After/Control/Impact framework to evaluate the short-term consequences of treatments on numerous ecological properties. We collected pre-treatment and one year post-treatment data on NF and partner agencies’ lands, in 66 plots distributed across seven treatment units and nearby untreated areas. Our results reflected progress toward several treatment objectives: treated areas had lower tree density and basal area, greater openness, no increase in exotic understory plants, no decrease in native understory plants, and no decrease in use by tree squirrels and ungulates. However, some findings suggested the need for adaptive modification of both treatment prescriptions and monitoring protocols: treatments did not promote heterogeneity of stand structure, and monitoring methods may not have been robust enough to detect changes in surface fuels. Our study highlights both the effective aspects of these restoration treatments, and the importance of initiating and continuing collaborative science-based monitoring to improve the outcomes of broad-scale forest restoration efforts.

  13. Forest Fire Smoldering Emissions from Ponderosa Pine Duff in Central Washington

    Science.gov (United States)

    Baker, S. P.; Lincoln, E.; Page, W.; Richardson, M.

    2017-12-01

    Forest fire smoldering combustion is a significant contribution to pollution and carbon emissions. Smoldering combustion produces the majority of carbon monoxide (CO), methane (CH4), volatile organic compounds (VOC), and fine particulate matter (PM2.5) emitted by forest fires when it occurs. The emission factor for PM2.5 and many VOCs are correlated with the modified combustion efficiency (MCE), which is the ratio of CO2 emitted, to the sum of emitted CO2 and CO. MCE is a measure of the relative ratio of flaming and smoldering combustion, but its relationship to the physical fire process is poorly studied. We measured carbon emission rates and individual emission factors for CO, CO2, CH4, and VOC's from smoldering combustion on Ponderosa pine /Douglas-Fir forest sites in central Washington. The emission factor results are linked with concurrent thermal measurements made at various depths in the duff and surface IR camera imagery. The MCE value ranged from .80 to .91 and are correlated with emission factors for 24 carbon compounds. Other data collected were fuel moistures and duff temperatures at depth increments. This goal of this research is the creation of a database to better predict the impacts of air pollution resulting from burns leading to smoldering combustion.

  14. Diagnosis & Correction of Soil Nutrient Limitations in Intensively managed southern pine forests

    Energy Technology Data Exchange (ETDEWEB)

    University of Florida

    2002-10-25

    Forest productivity is one manner to sequester carbon and it is a renewable energy source. Likewise, efficient use of fertilization can be a significant energy savings. To date, site-specific use of fertilization for the purpose of maximizing forest productivity has not been well developed. Site evaluation of nutrient deficiencies is primarily based on empirical approaches to soil testing and plot fertilizer tests with little consideration for soil water regimes and contributing site factors. This project uses mass flow diffusion theory in a modeling context, combined with process level knowledge of soil chemistry, to evaluate nutrient bioavailability to fast-growing juvenile forest stands growing on coastal plain Spodosols of the southeastern U.S. The model is not soil or site specific and should be useful for a wide range of soil management/nutrient management conditions. In order to use the model, field data of fast-growing southern pine needed to be measured and used in the validation of the model. The field aspect of the study was mainly to provide data that could be used to verify the model. However, we learned much about the growth and development of fast growing loblolly. Carbon allocation patterns, root shoot relationships and leaf area root relationships proved to be new, important information. The Project Objectives were to: (1) Develop a mechanistic nutrient management model based on the COMP8 uptake model. (2) Collect field data that could be used to verify and test the model. (3) Model testing.

  15. Resilience to seasonal heat wave episodes in a Mediterranean pine forest.

    Science.gov (United States)

    Tatarinov, Fedor; Rotenberg, Eyal; Maseyk, Kadmiel; Ogée, Jérôme; Klein, Tamir; Yakir, Dan

    2016-04-01

    Short-term, intense heat waves (hamsins) are common in the eastern Mediterranean region and provide an opportunity to study the resilience of forests to such events that are predicted to increase in frequency and intensity. The response of a 50-yr-old Aleppo pine (Pinus halepensis) forest to hamsin events lasting 1-7 d was studied using 10 yr of eddy covariance and sap flow measurements. The highest frequency of heat waves was c. four per month, coinciding with the peak productivity period (March-April). During these events, net ecosystem carbon exchange (NEE) and canopy conductance (gc ) decreased by c. 60%, but evapotranspiration (ET) showed little change. Fast recovery was also observed with fluxes reaching pre-stress values within a day following the event. NEE and gc showed a strong response to vapor pressure deficit that weakened as soil moisture decreased, while sap flow was primarily responding to changes in soil moisture. On an annual scale, heat waves reduced NEE and gross primary productivity by c. 15% and 4%, respectively. Forest resilience to short-term extreme events such as heat waves is probably a key to its survival and must be accounted for to better predict the increasing impact on productivity and survival of such events in future climates. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  16. Retention of seed trees fails to lifeboat ectomycorrhizal fungal diversity in harvested Scots pine forests.

    Science.gov (United States)

    Varenius, Kerstin; Lindahl, Björn D; Dahlberg, Anders

    2017-09-01

    Fennoscandian forestry has in the past decades changed from natural regeneration of forests towards replantation of clear-cuts, which negatively impacts ectomycorrhizal fungal (EMF) diversity. Retention of trees during harvesting enables EMF survival, and we therefore expected EMF communities to be more similar to those in old natural stands after forest regeneration using seed trees compared to full clear-cutting and replanting. We sequenced fungal internal transcribed spacer 2 (ITS2) amplicons to assess EMF communities in 10- to 60-year-old Scots pine stands regenerated either using seed trees or through replanting of clear-cuts with old natural stands as reference. We also investigated local EMF communities around retained old trees. We found that retention of seed trees failed to mitigate the impact of harvesting on EMF community composition and diversity. With increasing stand age, EMF communities became increasingly similar to those in old natural stands and permanently retained trees maintained EMF locally. From our observations, we conclude that EMF communities, at least common species, post-harvest are more influenced by environmental filtering, resulting from environmental changes induced by harvest, than by the continuity of trees. These results suggest that retention of intact forest patches is a more efficient way to conserve EMF diversity than retaining dispersed single trees. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Ponderosa pine ecosystems

    Science.gov (United States)

    Russell T. Graham; Theresa B. Jain

    2005-01-01

    Ponderosa pine is a wide-ranging conifer occurring throughout the United States, southern Canada, and northern Mexico. Since the 1800s, ponderosa pine forests have fueled the economies of the West. In western North America, ponderosa pine grows predominantly in the moist and dry forests. In the Black Hills of South Dakota and the southern portion of its range, the...

  18. Effects of artificial defoliation of pines on the structure and physiology of the soil fungal community of a mixed pine-spruce forest

    Science.gov (United States)

    Cullings, Ken; Raleigh, Christopher; New, Michael H.; Henson, Joan

    2005-01-01

    Loss of photosynthetic area can affect soil microbial communities by altering the availability of fixed carbon. We used denaturing gradient gel electrophoresis (DGGE) and Biolog filamentous-fungus plates to determine the effects of artificial defoliation of pines in a mixed pine-spruce forest on the composition of the fungal community in a forest soil. As measured by DGGE, two fungal species were affected significantly by the defoliation of pines (P the frequency of members of the ectomycorrhizal fungus genus Cenococcum decreased significantly, while the frequency of organisms of an unidentified soil fungus increased. The decrease in the amount of Cenococcum organisms may have occurred because of the formation of extensive hyphal networks by species of this genus, which require more of the carbon fixed by their host, or because this fungus is dependent upon quantitative differences in spruce root exudates. The defoliation of pines did not affect the overall composition of the soil fungal community or fungal-species richness (number of species per core). Biolog filamentous-fungus plate assays indicated a significant increase (P the number of carbon substrates utilized by the soil fungi and the rate at which these substrates were used, which could indicate an increase in fungal-species richness. Thus, either small changes in the soil fungal community give rise to significant increases in physiological capabilities or PCR bias limits the reliability of the DGGE results. These data indicate that combined genetic and physiological assessments of the soil fungal community are needed to accurately assess the effect of disturbance on indigenous microbial systems.

  19. Aerial survey of red pine plantations for sirococcus shoot blight. Forest research report No. 46

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    A total of 849 red pine plantation diagrams were collected from the forest community and sketched onto 1:50,000 scale topographic maps. An aerial assessment was conducted beginning in the western counties in October 1990 and continuing eastward through to February 1991. Visual assessments were made for occurrence and severity of symptoms according to the average percentage of shoots affected per infected tree. General assessments on the height of plantations were also made, and each plantation was labelled as young (less than or equal to 3 m in height), pole (between 4 m and 6 m in height), or immature-mature (greater than 6 m in height). This research provides the results of the survey.

  20. Effects of drought and irrigation on ecosystem functioning in a mature Scots pine forest

    Science.gov (United States)

    Dobbertin, Matthias; Brunner, Ivano; Egli, Simon; Eilmann, Britta; Graf Pannatier, Eisabeth; Schleppi, Patrick; Zingg, Andreas; Rigling, Andreas

    2010-05-01

    Climate change is expected to increase temperature and reduce summer precipitation in Switzerland. To study the expected effects of increased drought in mature forests two different approaches are in general possible: water can be partially or completely removed from the ecosystems via above- or below-canopy roofs or water can be added to already drought-prone ecosystems. Both methods have advantages and disadvantages. In our study water was added to a mature 90-year old Scots pine (Pinus sylvestris L.) forest with a few singe pubescent oaks (Quercus pubescens Willd.), located in the valley bottom of the driest region of Switzerland (Valais). In Valais, Scots pines are declining, usually with increased mortality rates following drought years. It was therefore of special interest to study here how water addition is changing forest ecosystem functioning. The irrigation experiment started in the summer of 2003. Out of eight 0.1 ha experimental plots, four were randomly selected for irrigation, the other four left as a control. Irrigation occurred during rainless nights between April and October, doubling the annual rainfall amount from 650 to 1300 mm. Irrigation water, taken from a near-by irrigation channel, added some nutrients to the plots, but nutrients which were deficient on the site, e.g. nitrogen and phosphorus, were not altered. Tree diameter, tree height and crown width were assessed before the start of the irrigation in winter 2002/2003 and after 7 years of the experiment in 2009/2010. Tree crown transparency (lack of foliage) and leaf area index (LAI) were annually assessed. Additionally, tree mortality was annually evaluated. Mycorrhizal fruit bodies were identified and counted at weekly intervals from 2003 until 2007. Root samples were taken in 2004 and 2005. In 2004 and 2005 wood formation of thirteen trees was analysed in weekly or biweekly intervals using the pinning method. These trees were felled in 2006 for stem, shoot and needle growth analysis

  1. Defoliating Insect Mass Outbreak Affects Soil N Fluxes and Tree N Nutrition in Scots Pine Forests

    Directory of Open Access Journals (Sweden)

    Maren M. Grüning

    2017-06-01

    Full Text Available Biotic stress by mass outbreaks of defoliating pest insects does not only affect tree performance by reducing its photosynthetic capacity, but also changes N cycling in the soil of forest ecosystems. However, how insect induced defoliation affects soil N fluxes and, in turn, tree N nutrition is not well-studied. In the present study, we quantified N input and output fluxes via dry matter input, throughfall, and soil leachates. Furthermore, we investigated the effects of mass insect herbivory on tree N acquisition (i.e., organic and inorganic 15N net uptake capacity of fine roots as well as N pools in fine roots and needles in a Scots pine (Pinus sylvestris L. forest over an entire vegetation period. Plots were either infested by the nun moth (Lymantria monacha L. or served as controls. Our results show an increased N input by insect feces, litter, and throughfall at the infested plots compared to controls, as well as increased leaching of nitrate. However, the additional N input into the soil did not increase, but reduce inorganic and organic net N uptake capacity of Scots pine roots. N pools in the fine roots and needles of infested trees showed an accumulation of total N, amino acid-N, protein-N, and structural N in the roots and the remaining needles as a compensatory response triggered by defoliation. Thus, although soil N availability was increased via surplus N input, trees did not respond with an increased N acquisition, but rather invested resources into defense by accumulation of amino acid-N and protein-N as a survival strategy.

  2. Defoliating Insect Mass Outbreak Affects Soil N Fluxes and Tree N Nutrition in Scots Pine Forests.

    Science.gov (United States)

    Grüning, Maren M; Simon, Judy; Rennenberg, Heinz; L-M-Arnold, Anne

    2017-01-01

    Biotic stress by mass outbreaks of defoliating pest insects does not only affect tree performance by reducing its photosynthetic capacity, but also changes N cycling in the soil of forest ecosystems. However, how insect induced defoliation affects soil N fluxes and, in turn, tree N nutrition is not well-studied. In the present study, we quantified N input and output fluxes via dry matter input, throughfall, and soil leachates. Furthermore, we investigated the effects of mass insect herbivory on tree N acquisition (i.e., organic and inorganic 15 N net uptake capacity of fine roots) as well as N pools in fine roots and needles in a Scots pine ( Pinus sylvestris L.) forest over an entire vegetation period. Plots were either infested by the nun moth ( Lymantria monacha L.) or served as controls. Our results show an increased N input by insect feces, litter, and throughfall at the infested plots compared to controls, as well as increased leaching of nitrate. However, the additional N input into the soil did not increase, but reduce inorganic and organic net N uptake capacity of Scots pine roots. N pools in the fine roots and needles of infested trees showed an accumulation of total N, amino acid-N, protein-N, and structural N in the roots and the remaining needles as a compensatory response triggered by defoliation. Thus, although soil N availability was increased via surplus N input, trees did not respond with an increased N acquisition, but rather invested resources into defense by accumulation of amino acid-N and protein-N as a survival strategy.

  3. Stand-replacing wildfires increase nitrification for decades in southwestern ponderosa pine forests.

    Science.gov (United States)

    Kurth, Valerie J; Hart, Stephen C; Ross, Christopher S; Kaye, Jason P; Fulé, Peter Z

    2014-05-01

    Stand-replacing wildfires are a novel disturbance within ponderosa pine (Pinus ponderosa) forests of the southwestern United States, and they can convert forests to grasslands or shrublands for decades. While most research shows that soil inorganic N pools and fluxes return to pre-fire levels within a few years, we wondered if vegetation conversion (ponderosa pine to bunchgrass) following stand-replacing fires might be accompanied by a long-term shift in N cycling processes. Using a 34-year stand-replacing wildfire chronosequence with paired, adjacent unburned patches, we examined the long-term dynamics of net and gross nitrogen (N) transformations. We hypothesized that N availability in burned patches would become more similar to those in unburned patches over time after fire as these areas become re-vegetated. Burned patches had higher net and gross nitrification rates than unburned patches (P < 0.01 for both), and nitrification accounted for a greater proportion of N mineralization in burned patches for both net (P < 0.01) and gross (P < 0.04) N transformation measurements. However, trends with time-after-fire were not observed for any other variables. Our findings contrast with previous work, which suggested that high nitrification rates are a short-term response to disturbance. Furthermore, high nitrification rates at our site were not simply correlated with the presence of herbaceous vegetation. Instead, we suggest that stand-replacing wildfire triggers a shift in N cycling that is maintained for at least three decades by various factors, including a shift from a woody to an herbaceous ecosystem and the presence of fire-deposited charcoal.

  4. The influence of pine forests of different ages on the biological activity of layland soils in the middle Angara River basin

    Science.gov (United States)

    Sorokina, O. A.; Sorokin, N. D.

    2007-05-01

    The influence of pine forests of different ages (from 25 to 85 years) restoring on old plow land soils is reflected in the biological processes proceeding in them. The drastic decrease in the absolute and relative number of actinomycetes, along with an increase of the fungal population in the microbial complexes of the soils (within the whole profiles), indicates that the microbocenoses acquire “forest” properties. In the soils under the younger pine forests, the processes of microbiological mineralization and specific respiration activity are more active than in the soils under the older pine forests. With the age of the pine forests, the soil profiles become more differentiated according to the eluvial-illuvial type.

  5. Carbon and Water Exchanges in a Chronosequence of Temperate White Pine Forest

    Science.gov (United States)

    Arain, M.; Restrepo, N.; Pejam, M.; Khomik, M.

    2003-12-01

    Quantification of carbon sink or source strengths of temperate forest ecosystems, growing in northern mid-latitudes, is essential to resolve uncertainties in carbon balance of the world's terrestrial ecosystems. Long-term flux measurements are needed to quantify seasonal and annual variability of carbon and water exchanges from these ecosystems and to relate the variability to environmental and physiological factors. Such long-term measurements are of particular interest for different stand developmental stages. An understanding of environmental control factors is necessary to improve predictive capabilities of terrestrial carbon and water cycles. A long-term year-round measurement program has been initiated to observe energy, water vapour, and carbon dioxide fluxes in a chronosequence of white pine (Pinus Strobus) forests in southeastern Canada. White pine is an important species in the North American landscape because of its ability to adapt to dry environments. White pine efficiently grows on coarse and sandy soils, where other deciduous and conifer species cannot survive. Generally, it is the first woody species to flourish after disturbances such as fire and clearing. The climate at the study site is temperate, with a mean annual temperature of 8 degree C and a mean annual precipitation of about 800 mm. The growing season is one of the longest in Canada, with at least 150 frost-free days. Measurements at the site began in June 2002 and are continuing at present. Flux measurements at the 60 year old stand are being made using a close-path eddy covariance (EC) system, while fluxes at the three younger stands (30, 15 and 1 year old) are being measured over 10 to 20 day periods using a roving open-path EC system Soil respiration is being measured every 2-weeks across 50-m transects at all four sites using a mobile chamber system (LI-COR 6400). The mature stand was a sink of carbon with annual NEP value of 140 g C m-2 from June 2002 to May 2003. Gross ecosystem

  6. Individual variability of Scots pine Pinus sylvestris L. by the drought resistance features in forest-steppe pine forests of south Siberia

    Directory of Open Access Journals (Sweden)

    N. A. Tikhonova

    2016-10-01

    Full Text Available The drought resistance of trees in the Scots pine Pinus sylvestris L. populations was studied under forest steppe conditions of southern Siberia. We found large differences amongthe treesin the time and rate of needles dehydration. In the populations of the more arid growing conditions (Shira, Balgazyn the rate of loss 50 % of the water was three to four times lower than in the population of the more favorable conditions for growth (Minusinsk. It has been established that the variability of water-holding capacity of needles from individual trees in populations varies from high to very high levels. On the contrary, for the water absorption capacity of needles characteristically has variability, as within population and between them. Is marked a great assessment reliability of water holding capacity of the needles under the pooled analysis of absolute and relative indicators of dynamics of the needles degradration. We investigated the correlation of needles’ water retention signs with a height and heterozygosity of trees. It was found that under more favorable conditions of the growth the large part of sample are the trees with a direct connection between heterozygosity and drought resistance of tree and in the worst conditions – with a reverse. The correlations of water-holding capacity of needles with the height of the tree are ambiguous: in the Minusinsk sample, the most of drought-resistant trees are characterized by better growth, in Balgazyn population – conversely. Some dwarf individuals from the Balgazyn and Shira populations in terms of drought tolerance are at same level as the typical trees, among the less drought-resistant trees found as dwarfs, and typical trees. It was concluded that there are trees in populations with different strategies to adaptation to the moisture deficit.

  7. Climate change will restrict ponderosa pine forest regeneration in the 21st century in absence of disturbance

    Science.gov (United States)

    Petrie, M. D.; Bradford, J. B.; Hubbard, R. M.; Lauenroth, W. K.; Andrews, C.

    2016-12-01

    The persistence of ponderosa pine forests and the ability for these forests to colonize new habitats in the 21st century will be influenced by how climate change supports ponderosa pine regeneration through the demographic processes of seed production, germination and survival. Yet, the way that climate change may support or restrict the frequency of successful regeneration is unclear. We developed a quantitative, criteria-based framework to estimate ponderosa pine regeneration potential (RP: a metric from 0-1) in response to climate forcings and environmental conditions. We used the SOILWAT ecosystem water balance model to simulate drivers of air and soil temperature, evaporation and soil moisture availability for 47 ponderosa pine sites across the western United States, using meteorological data from 1910-2014, and projections from nine General Circulation Models and the RCP 8.5 emissions scenario for 2020-2099. Climate change simulations increased the success of early developmental stages of seed production and germination, and supported 49.7% higher RP in 2020-2059 compared to averages from 1910-2014. As temperatures increased in 2060-2099, survival scores decreased, and RP was reduced by 50.3% compared to 1910-2014. Although the frequency of years with high RP did not change in 2060-2099 (12% of years), the frequency of years with very low RP increased from 25% to 58% of years. Thus, climate change will initially support higher RP and more favorable years in 2020-2059, yet will reduce average RP and the frequency of years with moderate regeneration support in 2060-2099. Forest regeneration is complex and not fully-understood, but our results suggest it is likely that climate change alone will instigate restrictions to the persistence and expansion of ponderosa pine in the 21st century.

  8. DEVELOPING AN INDEX FOR FOREST PRODUCTIVITY MAPPING - A CASE STUDY FOR MARITIME PINE PRODUCTION REGULATION IN PORTUGAL

    Directory of Open Access Journals (Sweden)

    Susana Mestre

    2018-02-01

    Full Text Available ABSTRACT Productivity is very dependent on the environmental and biotic factors present at the site where the forest species of interest is present. Forest site productivity is usually assessed using empirical models applied to inventory data providing discrete predictions. While the use of GIS-based models enables building a site productivity distribution map. Therefore, the aim of this study was to derive a productivity index using multivariate statistics and coupled GIS-geostatistics to obtain a forest productivity map. To that end, a study area vastly covered by naturally regenerated forests of maritime pine in central Portugal was used. First, a productivity index (PI was built based on Factorial Correspondence Analysis (FCA by incorporating a classical site index for the species and region (Sh25 - height index model and GIS-derived environmental variables (slope and aspect. After, the PI map was obtained by multi-Gaussian kriging and used as a GIS layer to evaluate maritime pine areas by productivity class (e.g., low, intermediate and high. In the end, the area control method was applied to assess the size and the number of compartments to establish by productivity class. The management compartments of equal productivity were digitized as GIS layer and organized in a temporal progression of stands’ age regularly available for cutting each year during a 50-year schedule. The methodological approach developed in this study proved that can be used to build forest productivity maps which are crucial tools to support forest production regulation.

  9. Ponderosa Pine Forest Restoration Treatment Longevity: Implications of Regeneration on Fire Hazard

    Directory of Open Access Journals (Sweden)

    Wade T. Tinkham

    2016-07-01

    Full Text Available Restoration of pine forests has become a priority for managers who are beginning to embrace ideas of highly heterogeneous forest structures that potentially encourages high levels of regeneration. This study utilizes stem-mapped stands to assess how simulated regeneration timing and magnitude influence longevity of reduced fire behavior by linking growth and yield model outputs to a crown fire prediction model. Treatment longevity was assessed as return time to within 10% of pre-treatment predicted wind speeds for the onset of passive (Torching and active (Crowning crown fire behavior. Treatment longevity in terms of Torching and Crowning was reduced 5 years for every 550 and 150 seedlings ha−1, respectively. Introducing regeneration as a single pulse further reduced Torching treatment longevity 10 years compared to other regeneration distributions. Crowning treatment longevity increased at higher site indices, where a 6 m increase in site index increased longevity 4.5 year. This result was contrary to expectations that canopy openings after treatments would close faster on higher productivity sites. Additionally, Torching longevity was influenced by the rate of crown recession, were reducing the recession rate decreased longevity in areas with higher site indices. These dependencies highlight a need for research exploring stand development in heterogeneous sites.

  10. Monitoring endophyte populations in pine plantations and native oak forests in Northern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Alvarez, P.; Martin-Garcia, J.; Rodriguez-Ceinos, S.; Diez, J. J.

    2012-07-01

    The replacement of native forest with plantations of other species may have important impacts on ecosystems. Some of these impacts have been widely studied, but very little is known about the effects on fungal communities and specifically endo phytic fungi. In this study, endophyte assemblages in pine plantations (Pinus sylvestris, P. nigra and P. pinaster) and native oak forests (Quercus pyrenaica) in the north of the province of Palencia (Spain) were analyzed. For this purpose, samples of needles/leaves and twigs were collected from three trees in each of three plots sampled per host species. The samples were later processed in the laboratory to identify all of the endo phytic species present. In addition, an exhaustive survey was carried out of the twelve sites to collect data on the environmental, crown condition, dendrometric and soil variables that may affect the distribution of the fungi. The endophyte assemblages isolated from P. sylvestris and P. nigra were closely related to each other, but were different from those isolated from P. pinaster. The endophytes isolated from Q. pyrenaica were less closely related to those from the other hosts, and therefore preservation of oak stands is important to prevent the loss of fungal diversity. Finally, the distribution of the endophyte communities was related to some of the environmental variables considered. (Author) 42 refs.

  11. Spatial variability of turbulent fluxes in the roughness sublayer of an even-aged pine forest

    Science.gov (United States)

    Katul, G.; Hsieh, C.-I.; Bowling, D.; Clark, K.; Shurpali, N.; Turnipseed, A.; Albertson, J.; Tu, K.; Hollinger, D.; Evans, B. M.; Offerle, B.; Anderson, D.; Ellsworth, D.; Vogel, C.; Oren, R.

    1999-01-01

    The spatial variability of turbulent flow statistics in the roughness sublayer (RSL) of a uniform even-aged 14 m (= h) tall loblolly pine forest was investigated experimentally. Using seven existing walkup towers at this stand, high frequency velocity, temperature, water vapour and carbon dioxide concentrations were measured at 15.5 m above the ground surface from October 6 to 10 in 1997. These seven towers were separated by at least 100 m from each other. The objective of this study was to examine whether single tower turbulence statistics measurements represent the flow properties of RSL turbulence above a uniform even-aged managed loblolly pine forest as a best-case scenario for natural forested ecosystems. From the intensive space-time series measurements, it was demonstrated that standard deviations of longitudinal and vertical velocities (??(u), ??(w)) and temperature (??(T)) are more planar homogeneous than their vertical flux of momentum (u(*)2) and sensible heat (H) counterparts. Also, the measured H is more horizontally homogeneous when compared to fluxes of other scalar entities such as CO2 and water vapour. While the spatial variability in fluxes was significant (> 15%), this unique data set confirmed that single tower measurements represent the 'canonical' structure of single-point RSL turbulence statistics, especially flux-variance relationships. Implications to extending the 'moving-equilibrium' hypothesis for RSL flows are discussed. The spatial variability in all RSL flow variables was not constant in time and varied strongly with spatially averaged friction velocity u(*), especially when u(*) was small. It is shown that flow properties derived from two-point temporal statistics such as correlation functions are more sensitive to local variability in leaf area density when compared to single point flow statistics. Specifically, that the local relationship between the reciprocal of the vertical velocity integral time scale (I(w)) and the arrival

  12. The effect of temperature on forest production in Canada, Finland and Sweden. Predicted effects of a global warming on production of lodgepole pine and Scots pine in the northern boreal forest

    International Nuclear Information System (INIS)

    Fries, Anders

    1998-01-01

    The aims of this study were to analyse relationships between forest production and climatic factors under different biogeoclimatic conditions and, thus, to enhance our ability to predict changes in production following temperature increases. Production in the IUFRO 70/71 provenance test series with lodgepole pine (Pinus contorta var. latifolia) was correlated to climate data from adjacent meteorological stations. Field-tests in Canada (British Columbia and the Yukon) and Scandinavia (Finland and Sweden) were evaluated about 20 years after planting. The temperature regime was strongly correlated to forest production in the northern boreal forest regions. The temperature during the growing season as a whole and the length of it seem to be more important than the maximum summer temperature. The relationship between production and temperature was weaker in Canada than in Scandinavia, and production increased generally more on poor and intermediate sites than on rich sites. According to the presented algorithms, an increase in the temperature sum from 600 to 1200 degree days, would theoretically result in an increase in site index of between 5 and 13 m for lodgepole pine, and slightly lower for Scots pine. The highest increases would occur in Scandinavia. Temperature plots show that, especially in northern Scandinavia, a higher mean temperature would prolong the growing season, and this may make short spells with above 0 deg C-temperatures during the dormant period. Together with drought during the growing season, this may increase the frequency of climate-related frost damage

  13. Comparison of vegetation patterns and soil nutrient relations in an oak-pine forest and a mixed deciduous forest on Long Island, New York

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, S.C.; Curtis, P.S.

    1980-11-01

    An analysis of soil nutrient relations in two forest communities on Long Island, NY, yielded a correlation between the fertility of the top-soil and vegetational composition. The oak-pine forest soils at Brookhaven National Laboratory contain lower average concentrations of NH/sub 3/, Ca, K, and organic matter than the mixed deciduous forest soils in the Stony Brook area. The pH of the topsoil is also more acidic at Brookhaven. The observed differences between localities are greater than within-locality differences between the two soil series tested (Plymouth and Riverhead), which are common to both localities. Nutrient concentrations in the subsoil are not consistently correlated with either locality or soil series, although organic matter and NH/sub 3/ show significantly higher concentrations at Stony Brook. Supporting data on density and basal area of trees and coverage of shrubs and herbs also reveals significant variation between the two forest communities. An ordination of the vegetation data shows higher similarity within than between localities, while no obvious pattern of within-locality variation due to soil series treatments is apparent. These data support the hypothesis that fertility gradients may influence forest community composition and structure. This hypothesis is discussed with reference to vegetation-soil interactions and other factors, such as frequency of burning, which may direct the future development of the Brookhaven oak-pine forest.

  14. Initial Response of Pine Seedlings and Weeds to Dried Sewage Sludge in Rehabilitation of an Eroded Forest Site

    Science.gov (United States)

    Charles R. Berry

    1977-01-01

    Dried sewage sludge was applied at rates of 0, 17, 34, and 69 metric tons/ha on a badly eroded forest site in the Piedmont region of northeast Georgia. Production of weed bio mass varied directly with amount of sludge applied. Heigh growth for both shortleafand loblolly pine seedlings appeared to be greater on plots receiving 17 metric tons of sludge/ha, bu differences...

  15. Pile burning creates a fifty-year legacy of openings in regenerating lodgepole pine forests in Colorado

    Science.gov (United States)

    Charles C. Rhoades; Paula J. Fornwalt

    2015-01-01

    Pile burning is a common means of disposing the woody residues of logging and for post-harvest site preparation operations, in spite of the practice’s potential negative effects. To examine the long-term implications of this practice we established a 50-year sequence of pile burns within recovering clear cuts in lodgepole pine forests. We compared tree, shrub and...

  16. Carbon Stocks and Climate Change: Management Implications in Northern Arizona Ponderosa Pine Forests

    Directory of Open Access Journals (Sweden)

    Benjamin Bagdon

    2014-04-01

    Full Text Available Researchers have observed climate-driven shifts of forest types to higher elevations in the Southwestern US and predict further migration coupled with large-scale mortality events proportional to increases in radiative forcing. Range contractions of forests are likely to impact the total carbon stored within a stand. This study examines the dynamics of Pinus ponderosa stands under three climate change scenarios in Northern Arizona using the Climate Forest Vegetation Simulator (Climate-FVS model to project changes in carbon pools. A sample of 90 stands were grouped according to three elevational ranges; low- (1951 to 2194 m, mid- (2194 to 2499 m, and high- (2499 to 2682 m. elevation stands. Growth, mortality, and carbon stores were simulated in the Climate-FVS over a 100 year timespan. We further simulated three management scenarios for each elevational gradient and climate scenario. Management included (1 a no-management scenario, (2 an intensive-management scenario characterized by thinning from below to a residual basal area (BA of 18 m2/ha in conjunction with a prescribed burn every 10 years, and (3 a moderate-management scenario characterized by a thin-from-below treatment to a residual BA of 28 m2/ha coupled with a prescribed burn every 20 years. Results indicate that any increase in aridity due to climate change will produce substantial mortality throughout the elevational range of ponderosa pine stands, with lower elevation stands projected to experience the most devastating effects. Management was only effective for the intensive-management scenario; stands receiving this treatment schedule maintained moderately consistent levels of basal area and demonstrated a higher level of resilience to climate change relative to the two other management scenarios. The results of this study indicate that management can improve resiliency to climate change, however, resource managers may need to employ more intensive thinning treatments than

  17. Burn Severity Dominates Understory Plant Community Response to Fire in Xeric Jack Pine Forests

    Directory of Open Access Journals (Sweden)

    Bradley D. Pinno

    2016-04-01

    Full Text Available Fire is the most common disturbance in northern boreal forests, and large fires are often associated with highly variable burn severities across the burnt area. We studied the understory plant community response to a range of burn severities and pre-fire stand age four growing seasons after the 2011 Richardson Fire in xeric jack pine forests of northern Alberta, Canada. Burn severity had the greatest impact on post-fire plant communities, while pre-fire stand age did not have a significant impact. Total plant species richness and cover decreased with disturbance severity, such that the greatest richness was in low severity burns (average 28 species per 1-m2 quadrat and plant cover was lowest in the high severity burns (average 16%. However, the response of individual plant groups differed. Lichens and bryophytes were most common in low severity burns and were effectively eliminated from the regenerating plant community at higher burn severities. In contrast, graminoid cover and richness were positively related to burn severity, while forbs did not respond significantly to burn severity, but were impacted by changes in soil chemistry with increased cover at pH >4.9. Our results indicate the importance of non-vascular plants to the overall plant community in this harsh environment and that the plant community is environmentally limited rather than recruitment or competition limited, as is often the case in more mesic forest types. If fire frequency and severity increase as predicted, we may see a shift in plant communities from stress-tolerant species, such as lichens and ericaceous shrubs, to more colonizing species, such as certain graminoids.

  18. Distribution of black carbon in ponderosa pine forest floor and soils following the High Park wildfire

    Science.gov (United States)

    Boot, C. M.; Haddix, M.; Paustian, K.; Cotrufo, M. F.

    2015-05-01

    Biomass burning produces black carbon (BC), effectively transferring a fraction of the biomass C from an actively cycling pool to a passive C pool, which may be stored in the soil. Yet the timescales and mechanisms for incorporation of BC into the soil profile are not well understood. The High Park fire (HPF), which occurred in northwestern Colorado in the summer of 2012, provided an opportunity to study the effects of both fire severity and geomorphology on properties of carbon (C), nitrogen (N) and BC in the Cache La Poudre River drainage. We sampled montane ponderosa pine forest floor (litter plus O-horizon) and soils at 0-5 and 5-15 cm depth 4 months post-fire in order to examine the effects of slope and burn severity on %C, C stocks, %N and BC. We used the benzene polycarboxylic acid (BPCA) method for quantifying BC. With regard to slope, we found that steeper slopes had higher C : N than shallow slopes but that there was no difference in BPCA-C content or stocks. BC content was greatest in the forest floor at burned sites (19 g BPCA-C kg-1 C), while BC stocks were greatest in the 5-15 cm subsurface soils (23 g BPCA-C m-2). At the time of sampling, unburned and burned soils had equivalent BC content, indicating none of the BC deposited on the land surface post-fire had been incorporated into either the 0-5 or 5-15 cm soil layers. The ratio of B6CA : total BPCAs, an index of the degree of aromatic C condensation, suggested that BC in the 5-15 cm soil layer may have been formed at higher temperatures or experienced selective degradation relative to the forest floor and 0-5 cm soils. Total BC soil stocks were relatively low compared to other fire-prone grassland and boreal forest systems, indicating most of the BC produced in this system is likely lost, either through erosion events, degradation or translocation to deeper soils. Future work examining mechanisms for BC losses from forest soils will be required for understanding the role BC plays in the global

  19. Strategies for preventing invasive plant outbreaks after prescribed fire in ponderosa pine forest

    Science.gov (United States)

    Symstad, Amy J.; Newton, Wesley E.; Swanson, Daniel J.

    2014-01-01

    Land managers use prescribed fire to return a vital process to fire-adapted ecosystems, restore forest structure from a state altered by long-term fire suppression, and reduce wildfire intensity. However, fire often produces favorable conditions for invasive plant species, particularly if it is intense enough to reveal bare mineral soil and open previously closed canopies. Understanding the environmental or fire characteristics that explain post-fire invasive plant abundance would aid managers in efficiently finding and quickly responding to fire-caused infestations. To that end, we used an information-theoretic model-selection approach to assess the relative importance of abiotic environmental characteristics (topoedaphic position, distance from roads), pre-and post-fire biotic environmental characteristics (forest structure, understory vegetation, fuel load), and prescribed fire severity (measured in four different ways) in explaining invasive plant cover in ponderosa pine forest in South Dakota’s Black Hills. Environmental characteristics (distance from roads and post-fire forest structure) alone provided the most explanation of variation (26%) in post-fire cover of Verbascum thapsus (common mullein), but a combination of surface fire severity and environmental characteristics (pre-fire forest structure and distance from roads) explained 36–39% of the variation in post-fire cover of Cirsium arvense (Canada thistle) and all invasives together. For four species and all invasives together, their pre-fire cover explained more variation (26–82%) in post-fire cover than environmental and fire characteristics did, suggesting one strategy for reducing post-fire invasive outbreaks may be to find and control invasives before the fire. Finding them may be difficult, however, since pre-fire environmental characteristics explained only 20% of variation in pre-fire total invasive cover, and less for individual species. Thus, moderating fire intensity or targeting areas

  20. Tree Regeneration Spatial Patterns in Ponderosa Pine Forests Following Stand-Replacing Fire: Influence of Topography and Neighbors

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    Justin P. Ziegler

    2017-10-01

    Full Text Available Shifting fire regimes alter forest structure assembly in ponderosa pine forests and may produce structural heterogeneity following stand-replacing fire due, in part, to fine-scale variability in growing environments. We mapped tree regeneration in eighteen plots 11 to 15 years after stand-replacing fire in Colorado and South Dakota, USA. We used point pattern analyses to examine the spatial pattern of tree locations and heights as well as the influence of tree interactions and topography on tree patterns. In these sparse, early-seral forests, we found that all species were spatially aggregated, partly attributable to the influence of (1 aspect and slope on conifers; (2 topographic position on quaking aspen; and (3 interspecific attraction between ponderosa pine and other species. Specifically, tree interactions were related to finer-scale patterns whereas topographic effects influenced coarse-scale patterns. Spatial structures of heights revealed conspecific size hierarchies with taller trees in denser neighborhoods. Topography and heterospecific tree interactions had nominal effect on tree height spatial structure. Our results demonstrate how stand-replacing fires create heterogeneous forest structures and suggest that scale-dependent, and often facilitatory, rather than competitive, processes act on regenerating trees. These early-seral processes will establish potential pathways of stand development, affecting future forest dynamics and management options.

  1. Trends in Snag Populations in Drought-Stressed Mixed-Conifer and Ponderosa Pine Forests (1997–2007

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    Joseph L. Ganey

    2012-01-01

    Full Text Available Snags provide important biological legacies, resources for numerous species of native wildlife, and contribute to decay dynamics and ecological processes in forested ecosystems. We monitored trends in snag populations from 1997 to 2007 in drought-stressed mixed-conifer and ponderosa pine (Pinus ponderosa Dougl. ex Laws forests, northern Arizona. Median snag density increased by 75 and 90% in mixed-conifer and ponderosa pine forests, respectively, over this time period. Increased snag density was driven primarily by a large pulse in drought-mediated tree mortality from 2002 to 2007, following a smaller pulse from 1997 to 2002. Decay-class composition and size-class composition of snag populations changed in both forest types, and species composition changed in mixed-conifer forest. Increases in snag abundance may benefit some species of native wildlife in the short-term by providing increased foraging and nesting resources, but these increases may be unsustainable in the long term. Observed changes in snag recruitment and fall rates during the study illustrate the difficulty involved in modeling dynamics of those populations in an era of climate change and changing land management practices.

  2. Surface and canopy fuels vary widely in 24-yr old postfire lodgepole pine forests

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    Nelson, K. N.; Turner, M.; Romme, W. H.; Tinker, D. B.

    2013-12-01

    Extreme fire seasons have become common in western North America, and the extent of young postfire forests has grown as fire frequency and annual area burned have increased. These young forests will set the stage for future fires, but an assessment of fuel loads in young forests is lacking. The rate of fuel re-accumulation and fuels variability in postfire forest landscapes is needed to anticipate future fire occurrence and behavior in the American West. We studied fuel characteristics in young lodgepole pine forests that regenerated after the 1988 fires in Yellowstone National Park to address two questions: (1) How do surface fuel characteristics change with time-since-fire? (2) How do canopy and surface fuels vary across the Yellowstone landscape 24 years postfire? During summer 2012, we re-measured surface fuels in 11 plots that were established in 1996 (8 yrs post fire), and we measured surface and canopy fuels in 82 stands (each 0.25 ha) distributed across the Yellowstone post-1988 fire landscape. In the remeasured plots, surface fuel loads generally increased over the last 16 years. One-hr fuels did not change between sample dates, but all other fuel classes (i.e., 10-hr, 100-hr, and 1000-hr) increased by a factor of two or three. Within the sample timeframe, variability of fuel loads within stands decreased significantly. The coefficients of variation decreased for all fuel classes by 23% to 67%. Data from the 82 plots revealed that canopy and surface fuels in 24-year-old stands varied tremendously across the Yellowstone landscape. Live tree densities spanned 0 to 344,067 trees ha-1, producing a mean available canopy fuel load of 7.7 Mg ha-1 and a wide range from 0 to 47 Mg ha-1. Total surface fuel loads averaged 130 Mg ha-1 and ranged from 49 to 229 Mg ha-1, of which 90% was in the 1000-hr fuel class. The mass of fine surface fuels (i.e., litter/duff, 1-hr, 10-hr, and herbaceous fuels) and canopy fuels (i.e., foliage and 1-hr branches) were strongly and

  3. Diversity, abundance, and host relationships of avian malaria and related haemosporidians in New Mexico pine forests

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    Rosario A. Marroquin-Flores

    2017-08-01

    Full Text Available Avian malaria and related haemosporidian parasites (genera Haemoproteus, Plasmodium, and Leucocytozoon affect bird demography, species range limits, and community structure, yet they remain unsurveyed in most bird communities and populations. We conducted a community-level survey of these vector-transmitted parasites in New Mexico, USA, to describe their diversity, abundance, and host associations. We focused on the breeding-bird community in the transition zone between piñon-juniper woodland and ponderosa pine forests (elevational range: 2,150–2,460 m. We screened 186 birds representing 49 species using both standard PCR and microscopy techniques to detect infections of all three avian haemosporidian genera. We detected infections in 68 out of 186 birds (36.6%, the highest proportion of which were infected with Haemoproteus (20.9%, followed by Leucocytozoon (13.4%, then Plasmodium (8.0%. We sequenced mtDNA for 77 infections representing 43 haplotypes (25 Haemoproteus, 12 Leucocytozoon, 6 Plasmodium. When compared to all previously known haplotypes in the MalAvi and GenBank databases, 63% (27 of the haplotypes we recovered were novel. We found evidence for host specificity at the avian clade and species level, but this specificity was variable among parasite genera, in that Haemoproteus and Leucocytozoon were each restricted to three avian groups (out of six, while Plasmodium occurred in all groups except non-passerines. We found striking variation in infection rate among host species, with nearly universal infection among vireos and no infection among nuthatches. Using rarefaction and extrapolation, we estimated the total avian haemosporidian diversity to be 70 haplotypes (95% CI [43–98]; thus, we may have already sampled ∼60% of the diversity of avian haemosporidians in New Mexico pine forests. It is possible that future studies will find higher diversity in microhabitats or host species that are under-sampled or unsampled in the

  4. Modelling the Distribution of Forest-Dependent Species in Human-Dominated Landscapes: Patterns for the Pine Marten in Intensively Cultivated Lowlands.

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    Alessandro Balestrieri

    Full Text Available In recent years, the "forest-specialist" pine marten Martes martes has been reported to also occur also in largely fragmented, lowland landscapes of north-western Italy. The colonization of such an apparently unsuitable area provided the opportunity for investigating pine marten ecological requirements and predicting its potential south- and eastwards expansion. We collected available pine marten occurrence data in the flood plain of the River Po (N Italy and relate them to 11 environmental variables by developing nine Species Distribution Models. To account for inter-model variability we used average ensemble predictions (EP. EP predicted a total of 482 suitable patches (8.31% of the total study area for the pine marten. The main factors driving pine marten occurrence in the western River Po plain were the distance from watercourses and the distance from woods. EP suggested that the pine marten may further expand in the western lowland, whilst the negligible residual wood cover of large areas in the central and eastern plain makes the habitat unsuitable for the pine marten, except for some riparian corridors and the pine wood patches bordering the Adriatic coast. Based on our results, conservation strategies should seek to preserve remnant forest patches and enhance the functional connectivity provided by riparian corridors.

  5. Twenty-Five year (1982-2007) history of lodgepole pine dwarf mistletoe animal vectors and ethephon control on the Fraser Experimental Forest in Colorado

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    Thomas. Nicholls

    2009-01-01

    This is a summary of the 25-year history of studies of mammal and bird vectors of lodgepole pine dwarf mistletoe (Arceuthobium americanum), ethephon control of dwarf mistletoe, and the ecology of the most important dwarf mistletoe vector, the gray jay (Persisoreus canadensis), on the USDA Forest Service, Fraser Experimental Forest...

  6. Long-term simulations of forest management impacts on carbon storage from loblolly pine plantations in the Southern U.S.

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    Huei-Jin Wang; Philip J. Radtke; Stephen P. Prisley

    2012-01-01

    Accounting for forest components in carbon accounting systems may be insufficient when substantial amounts of sequestered carbon are harvested and converted to wood products in use and in landfill. The potential of forest offset – in-woods aboveground carbon storage, carbon stored in harvested wood, and energy offset by burning harvested wood – from loblolly pine...

  7. Forest attributes and fuel loads of riparian vs. upland stands in mountain pine beetle infested watersheds, southern Rocky Mountains [Chapter 13

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    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...

  8. Variability in snowpack accumulation and ablation associated with mountain pine beetle infestation in western forests

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    Biederman, J. A.; Harpold, A. A.; Gochis, D. J.; Reed, D.; Brooks, P. D.

    2010-12-01

    Seasonal snowcover is a primary source of water to urban and agricultural regions in the western United States, where Mountain Pine Beetle (MPB) has caused rapid and extensive changes to vegetation in montane forests. Levels of MPB infestation in these seasonally snow-covered systems are unprecedented, and it is unknown how this will affect water yield, especially in changing climate conditions. To address this unknown we ask: How does snow accumulation and ablation vary across forest with differing levels of impact? Our study areas in the Rocky Mountains of CO and WY are similar in latitude, elevation and forest structure before infestation, but they vary in the intensity and timing of beetle infestation and tree mortality. We present a record for winter 2010 that includes continuous snow depth as well as stand-scale snow surveys at maximum accumulation. Additional measurements include snowfall, net radiation, temperature and wind speed as well as characterization of forest structure by leaf area index. In a stand uninfested by MPB, maximum snow depth was fairly uniform under canopy (mean = 86 cm, coefficient of variation = 0.021), while canopy gaps showed greater and more variable depth (mean = 117 cm, CV = 0.111). This is consistent with several studies demonstrating that snowfall into canopy gaps depends upon gap size, orientation, wind speed and storm size. In a stand impacted in 2007, snow depth under canopy was less uniform, and there were smaller differences in both mean depth and variability between canopy (mean = 93 cm, CV = 0.072) and gaps (mean = 97 cm, CV = 0.070), consistent with decreased canopy density. In a more recently infested (2009) stand with an intermediate level of MPB impact, mean snow depths were similar between canopy (96 cm, CV = 0.016) and gaps (95 cm, CV = 0.185) but gaps showed much greater variability, suggesting controls similar to those in effect in the uninfested stand. We further use these data to model snow accumulation and

  9. Trends in soil-vegetation dynamics in burned Mediterranean pine forests: the effects of soil properties

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    Wittenberg, L.; Malkinson, D.

    2009-04-01

    Fire can impact a variety of soil physical and chemical properties. These changes may result, given the fire severity and the local conditions, in decreased infiltration and increased runoff and erosion rates. Most of these changes are caused by complex interactions among eco-geomorphic processes which affect, in turn, the rehabilitation dynamics of the soil and the regeneration of the burnt vegetation. Following wildfire events in two forests growing on different soil types, we investigated runoff, erosion, nutrient export (specifically nitrogen and phosphorous) and vegetation recovery dynamics. The Biriya forest site, burned during the 2006 summer, is composed of two dominant lithological types: soft chalk and marl which are relatively impermeable. The rocks are usually overlain by relatively thick, up of to 80 cm, grayish-white Rendzina soil, which contains large amounts of dissolved carbonate. These carbonates serve as a limiting factor for vegetation growth. The planted forest in Biriya is comprised of monospecific stands of Pinus spp. and Cupressus spp. The Mt. Carmel area, which was last burned in the 2005 spring, represents a system of varied Mediterranean landscapes, differentiated by lithology, soils and vegetation. Lithology is mainly composed of limestone, dolomite, and chalk. The dominant soil is Brown Rendzina whilst in some locations Grey Rendzina and Terra Rossa can be found. The local vegetation is composed mainly of a complex of pine (Pinus halepensis), oak (Quercus calliprinos), Pistacia lentiscus and associations At each site several 3X3 m monitoring plots were established to collect runoff and sediment. In-plot vegetation changes were monitored by a sequence of aerial photographs captured using a 6 m pole-mounted camera. At the terra-rosa sites (Mt. Carmel) mean runoff coefficients were 2.18% during the first year after the fire and 1.6% in the second. Mean erosion rates also decreased, from 42 gr/m2 to 4 gr/m2. The recovering vegetation was

  10. Neural network modelling of rainfall interception in four different forest stands

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    İbrahim Yurtseven

    2013-11-01

    Full Text Available The objective of this study is to reveal whether it is possible to predict rainfall, through fall and stem flow in forest ecosystems with less effort, using several measurements of rainfall interception (hereafter ‘interception’ and an artificial neural network based linear regression model (ANN model. To this end, the Kerpe Research Forest in the province of Kocaeli, which houses stands of mixed deciduous-broadleaf forest (Castanea sativa Mill., Fagusorientalis Lipsky, Quercus spp., black pine (Pinus nigra Arnold, maritime pine (Pinus pinaster Aiton and Monterey pine (Pinus radiata D. Don, was selected study site. Four different forest stands were observed for a period of two years, during which rainfall, throughfall and stemflow measurements were conducted. These measurements were separately calculated for each individual stand, based on interception values and the use of stemflow data in strict accordance with the rainfall data, and the measured throughfall interceptionvalues were compared with values estimated by the ANN model.In this comparison, 70% of the total data was used for testing, and 30% was used for estimation and performance evaluation. No significant differences were found between values predicted with the help of the model and the measured values. In other words, interception values predicted by the ANN models were parallel with the measured values. In this study, the most success was achieved with the models of the Monterey pine stand (r2 = 0.9968; Mean Squared Error MSE = 0.16 and the mixed deciduous forest stand (r2 = 0.9964; MSE = 0.08, followed by models of the maritime pine stand (r2 = 0.9405; MSE = 1.27 and the black pine stand (r2 = 0.843, MSE = 17.36.

  11. Neural network modelling of rainfall interception in four different forest stands

    Directory of Open Access Journals (Sweden)

    Ibrahim Yurtseven

    2013-12-01

    Full Text Available The objective of this study is to reveal whether it is possible to predict rainfall, throughfall and stemflow in forest ecosystems with less effort, using several measurements of rainfall interception (hereafter ‘interception’ and an artificial neural network based linear regression model (ANN model. To this end, the Kerpe Research Forest in the province of Kocaeli, which houses stands of mixed deciduous-broadleaf forest (Castanea sativa Mill., Fagus orientalis Lipsky, Quercus spp., black pine (Pinus nigra Arnold, maritime pine (Pinus pinaster Aiton and Monterey pine (Pinus radiata D. Don, was selected study site. Four different forest stands were observed for a period of two years, during which rainfall, throughfall and stemflow measurements were conducted. These measurements were separately calculated for each individual stand, based on interception values and the use of stemflow data in strict accordance with the rainfall data, and the measured throughfall interception values were compared with values estimated by the ANN model. In this comparison, 70% of the total data was used for testing, and 30% was used for estimation and performance evaluation. No significant differences were found between values predicted with the help of the model and the measured values. In other words, interception values predicted by the ANN models were parallel with the measured values. In this study, the most success was achieved with the models of the Monterey pine stand (r2 = 0.9968; Mean Squared Error MSE = 0.16 and the mixed deciduous forest stand (r2 = 0.9964; MSE = 0.08, followed by models of the maritime pine stand (r2 = 0.9405; MSE = 1.27 and the black pine stand (r2 = 0.843, MSE = 17.36.

  12. Eddy covariance fluxes of acyl peroxy nitrates (PAN, PPN and MPAN above a Ponderosa pine forest

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    G. M. Wolfe

    2009-01-01

    Full Text Available During the Biosphere Effects on AeRosols and Photochemistry EXperiment 2007 (BEARPEX-2007, we observed eddy covariance (EC fluxes of speciated acyl peroxy nitrates (APNs, including peroxyacetyl nitrate (PAN, peroxypropionyl nitrate (PPN and peroxymethacryloyl nitrate (MPAN, above a Ponderosa pine forest in the western Sierra Nevada. All APN fluxes are net downward during the day, with a median midday PAN exchange velocity of −0.3 cm s−1; nighttime storage-corrected APN EC fluxes are smaller than daytime fluxes but still downward. Analysis with a standard resistance model shows that loss of PAN to the canopy is not controlled by turbulent or molecular diffusion. Stomatal uptake can account for 25 to 50% of the observed downward PAN flux. Vertical gradients in the PAN thermal decomposition (TD rate explain a similar fraction of the flux, suggesting that a significant portion of the PAN flux into the forest results from chemical processes in the canopy. The remaining "unidentified" portion of the net PAN flux (~15% is ascribed to deposition or reactive uptake on non-stomatal surfaces (e.g. leaf cuticles or soil. Shifts in temperature, moisture and ecosystem activity during the summer – fall transition alter the relative contribution of stomatal uptake, non-stomatal uptake and thermochemical gradients to the net PAN flux. Daytime PAN and MPAN exchange velocities are a factor of 3 smaller than those of PPN during the first two weeks of the measurement period, consistent with strong intra-canopy chemical production of PAN and MPAN during this period. Depositional loss of APNs can be 3–21% of the gross gas-phase TD loss depending on temperature. As a source of nitrogen to the biosphere, PAN deposition represents approximately 4–19% of that due to dry deposition of nitric acid at this site.

  13. Quantum Yields in Mixed-Conifer Forests and Ponderosa Pine Plantations

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    Wei, L.; Marshall, J. D.; Zhang, J.

    2008-12-01

    Most process-based physiological models require canopy quantum yield of photosynthesis as a starting point to simulate carbon sequestration and subsequently gross primary production (GPP). The quantum yield is a measure of photosynthetic efficiency expressed in moles of CO2 assimilated per mole of photons absorbed; the process is influenced by environmental factors. In the summer 2008, we measured quantum yields on both sun and shade leaves for four conifer species at five sites within Mica Creek Experimental Watershed (MCEW) in northern Idaho and one conifer species at three sites in northern California. The MCEW forest is typical of mixed conifer stands dominated by grand fir (Abies grandis (Douglas ex D. Don) Lindl.). In northern California, the three sites with contrasting site qualities are ponderosa pine (Pinus ponderosa C. Lawson var. ponderosa) plantations that were experimentally treated with vegetation control, fertilization, and a combination of both. We found that quantum yields in MCEW ranged from ~0.045 to ~0.075 mol CO2 per mol incident photon. However, there were no significant differences between canopy positions, or among sites or tree species. In northern California, the mean value of quantum yield of three sites was 0.051 mol CO2/mol incident photon. No significant difference in quantum yield was found between canopy positions, or among treatments or sites. The results suggest that these conifer species maintain relatively consistent quantum yield in both MCEW and northern California. This consistency simplifies the use of a process-based model to accurately predict forest productivity in these areas.

  14. Forest thinning and soil respiration in a ponderosa pine plantation in the Sierra Nevada.

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    Tang, Jianwu; Qi, Ye; Xu, Ming; Misson, Laurent; Goldstein, Allen H

    2005-01-01

    Soil respiration is controlled by soil temperature, soil water, fine roots, microbial activity, and soil physical and chemical properties. Forest thinning changes soil temperature, soil water content, and root density and activity, and thus changes soil respiration. We measured soil respiration monthly and soil temperature and volumetric soil water continuously in a young ponderosa pine (Pinus ponderosa Dougl. ex P. Laws. & C. Laws.) plantation in the Sierra Nevada Mountains in California from June 1998 to May 2000 (before a thinning that removed 30% of the biomass), and from May to December 2001 (after thinning). Thinning increased the spatial homogeneity of soil temperature and respiration. We conducted a multivariate analysis with two independent variables of soil temperature and water and a categorical variable representing the thinning event to simulate soil respiration and assess the effect of thinning. Thinning did not change the sensitivity of soil respiration to temperature or to water, but decreased total soil respiration by 13% at a given temperature and water content. This decrease in soil respiration was likely associated with the decrease in root density after thinning. With a model driven by continuous soil temperature and water time series, we estimated that total soil respiration was 948, 949 and 831 g C m(-2) year(-1) in the years 1999, 2000 and 2001, respectively. Although thinning reduced soil respiration at a given temperature and water content, because of natural climate variability and the thinning effect on soil temperature and water, actual cumulative soil respiration showed no clear trend following thinning. We conclude that the effect of forest thinning on soil respiration is the combined result of a decrease in root respiration, an increase in soil organic matter, and changes in soil temperature and water due to both thinning and interannual climate variability.

  15. Ethene, propene, butene and isoprene emissions from a ponderosa pine forest measured by relaxed eddy accumulation

    Science.gov (United States)

    Rhew, Robert C.; Deventer, Malte Julian; Turnipseed, Andrew A.; Warneke, Carsten; Ortega, John; Shen, Steve; Martinez, Luis; Koss, Abigail; Lerner, Brian M.; Gilman, Jessica B.; Smith, James N.; Guenther, Alex B.; de Gouw, Joost A.

    2017-11-01

    Alkenes are reactive hydrocarbons that influence local and regional atmospheric chemistry by playing important roles in the photochemical production of tropospheric ozone and in the formation of secondary organic aerosols. The simplest alkene, ethene (ethylene), is a major plant hormone and ripening agent for agricultural commodities. The group of light alkenes (C2-C4) originates from both biogenic and anthropogenic sources, but their biogenic sources are poorly characterized, with limited field-based flux observations. Here we report net ecosystem fluxes of light alkenes and isoprene from a semiarid ponderosa pine forest in the Rocky Mountains of Colorado, USA using the relaxed eddy accumulation (REA) technique during the summer of 2014. Ethene, propene, butene and isoprene emissions have strong diurnal cycles, with median daytime fluxes of 123, 95, 39 and 17 µg m-2 h-1, respectively. The fluxes were correlated with each other, followed general ecosystem trends of CO2 and water vapor, and showed similar sunlight and temperature response curves as other biogenic VOCs. The May through October flux, based on measurements and modeling, averaged 62, 52, 24 and 18 µg m-2 h-1 for ethene, propene, butene and isoprene, respectively. The light alkenes contribute significantly to the overall biogenic source of reactive hydrocarbons: roughly 18 % of the dominant biogenic VOC, 2-methyl-3-buten-2-ol. The measured ecosystem scale fluxes are 40-80 % larger than estimates used for global emissions models for this type of ecosystem.

  16. Thermal conditions within tree cavities in ponderosa pine (Pinus ponderosa) forests: potential implications for cavity users

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    Vierling, Kerri T.; Lorenz, Teresa J.; Cunningham, Patrick; Potterf, Kelsi

    2017-11-01

    Tree cavities provide critical roosting and breeding sites for multiple species, and thermal environments in these cavities are important to understand. Our objectives were to (1) describe thermal characteristics in cavities between June 3 and August 9, 2014, and (2) investigate the environmental factors that influence cavity temperatures. We placed iButtons in 84 different cavities in ponderosa pine (Pinus ponderosa) forests in central Washington, and took hourly measurements for at least 8 days in each cavity. Temperatures above 40 °C are generally lethal to developing avian embryos, and 18% of the cavities had internal temperatures of ≥ 40 °C for at least 1 h of each day. We modeled daily maximum cavity temperature, the amplitude of daily cavity temperatures, and the difference between the mean internal cavity and mean ambient temperatures as a function of several environmental variables. These variables included canopy cover, tree diameter at cavity height, cavity volume, entrance area, the hardness of the cavity body, the hardness of the cavity sill (which is the wood below the cavity entrance which forms the barrier between the cavity and the external environment), and sill width. Ambient temperature had the largest effect size for maximum cavity temperature and amplitude. Larger trees with harder sills may provide more thermally stable cavity environments, and decayed sills were positively associated with maximum cavity temperatures. Summer temperatures are projected to increase in this region, and additional research is needed to determine how the thermal environments of cavities will influence species occupancy, breeding, and survival.

  17. Analysis of the prescribed burning practice in the pine forest of northwestern Portugal.

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    Fernandes, P; Botelho, H

    2004-01-01

    The ignition of low-intensity fires in the dormant season in the pine stands of north-western Portugal seeks to reduce the existing fuel hazard without compromising site quality. The purpose of this study is to characterise this practice and assess its effectiveness, based on information resulting from the normal monitoring process at the management level, and using operational guidelines, fire behaviour models and a newly developed method to classify prescribed fire severity. Although the region's humid climate strongly constrains the activity of prescribed fire, 87% of the fires analysed were undertaken under acceptable meteorological and fuel moisture conditions. In fact, most operations achieved satisfactory results. On average, prescribed fire reduces by 96% the potential intensity of a wildfire occurring under extreme weather conditions, but 36% of the treated sites would still require heavy fire fighting resources to suppress such fire, and 17% would still carry it in the tree canopy. Only 10% of the prescribed burns have an excessive impact on trees or the forest floor, while 89% (normal fire weather) or 59% (extreme fire weather) comply with both ecological integrity maintenance and wildfire protection needs. Improved planning and monitoring procedures are recommended in order to overcome the current deficiencies.

  18. Post-fire management and recovery of a pine forest in Greece

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    I. Spanos

    2010-05-01

    Full Text Available The effects of management after fire in Pinus halepensis forests were assessed in northern Greece. Seeding, logging and building of log barriers were applied in burned sites and compared to a control site. Two years after treatment application, 70–80% of the ground in all sites was covered with vegetation. Seeding with herbaceous plants did not increase plant cover. Logging and building of log barriers negatively affected herbaceous species but increased woody species. During the first spring after fire, the highest numbers of P. halepensis seedlings were observed in the control site and the lowest number in the logged site. Logging and log barrier building had a negative effect on pine regeneration compared to control and seeding treatments. Woody plant composition was similar in control and seeding sites, with dominance of P. halepensis and Cistus species. A different pattern was observed in the logging and log-barrier sites with a low number of seeders and a high number of resprouter species.

  19. Growth and structure of a young Aleppo pine planted forest after thinning for diversification and wildfire prevention

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    J. Ruiz-Mirazo

    2013-04-01

    Full Text Available Aim of study: In the Mediterranean, low timber-production forests are frequently thinned to promote biodiversity and reduce wildfire risk, but few studies in the region have addressed such goals. The aim of this research was to compare six thinning regimes applied to create a fuelbreak in a young Aleppo pine (Pinus halepensis Mill. planted forest.Area of study: A semiarid continental high plateau in south-eastern Spain.Material and Methods: Three thinning intensities (Light, Medium and Heavy were combined with two thinning methods: i Random (tree selection, and ii Regular (tree spacing. Tree growth and stand structure measurements were made four years following treatments.Main results: Heavy Random thinning successfully transformed the regular tree plantation pattern into a close-to-random spatial tree distribution. Heavy Regular thinning (followed by the Medium Regular and Heavy Random regimes significantly reduced growth in stand basal area and biomass. Individual tree growth, in contrast, was greater in Heavy and Medium thinnings than in Light ones, which were similar to the Control.Research highlights: Heavy Random thinning seemed the most appropriate in a youngAleppo pine planted forest to reduce fire risk and artificial tree distribution simultaneously. Light Regular thinning avoids understocking the stand and may be the most suitable treatment for creating a fuelbreak when the undergrowth poses a high fire risk.Keywords: Pinus halepensis; Mediterranean; Forest structure; Tree growth; Wildfire risk; Diversity.

  20. Examining historical and current mixed-severity fire regimes in ponderosa pine and mixed-conifer forests of western North America.

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    Dennis C Odion

    Full Text Available There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of historical fire regimes in the ponderosa pine and mixed-conifer forests of western North America is therefore needed to define reference conditions and help maintain characteristic ecological diversity of these systems. We compiled landscape-scale evidence of historical fire severity patterns in the ponderosa pine and mixed-conifer forests from published literature sources and stand ages available from the Forest Inventory and Analysis program in the USA. The consensus from this evidence is that the traditional reference conditions of low-severity fire regimes are inaccurate for most forests of western North America. Instead, most forests appear to have been characterized by mixed-severity fire that included ecologically significant amounts of weather-driven, high-severity fire. Diverse forests in different stages of succession, with a high proportion in relatively young stages, occurred prior to fire exclusion. Over the past century, successional diversity created by fire decreased. Our findings suggest that ecological management goals that incorporate successional diversity created by fire may support characteristic biodiversity, whereas current attempts to "restore" forests to open, low-severity fire conditions may not align with historical reference conditions in

  1. Examining historical and current mixed-severity fire regimes in ponderosa pine and mixed-conifer forests of western North America.

    Science.gov (United States)

    Odion, Dennis C; Hanson, Chad T; Arsenault, André; Baker, William L; Dellasala, Dominick A; Hutto, Richard L; Klenner, Walt; Moritz, Max A; Sherriff, Rosemary L; Veblen, Thomas T; Williams, Mark A

    2014-01-01

    There is widespread concern that fire exclusion has led to an unprecedented threat of uncharacteristically severe fires in ponderosa pine (Pinus ponderosa Dougl. ex. Laws) and mixed-conifer forests of western North America. These extensive montane forests are considered to be adapted to a low/moderate-severity fire regime that maintained stands of relatively old trees. However, there is increasing recognition from landscape-scale assessments that, prior to any significant effects of fire exclusion, fires and forest structure were more variable in these forests. Biota in these forests are also dependent on the resources made available by higher-severity fire. A better understanding of historical fire regimes in the ponderosa pine and mixed-conifer forests of western North America is therefore needed to define reference conditions and help maintain characteristic ecological diversity of these systems. We compiled landscape-scale evidence of historical fire severity patterns in the ponderosa pine and mixed-conifer forests from published literature sources and stand ages available from the Forest Inventory and Analysis program in the USA. The consensus from this evidence is that the traditional reference conditions of low-severity fire regimes are inaccurate for most forests of western North America. Instead, most forests appear to have been characterized by mixed-severity fire that included ecologically significant amounts of weather-driven, high-severity fire. Diverse forests in different stages of succession, with a high proportion in relatively young stages, occurred prior to fire exclusion. Over the past century, successional diversity created by fire decreased. Our findings suggest that ecological management goals that incorporate successional diversity created by fire may support characteristic biodiversity, whereas current attempts to "restore" forests to open, low-severity fire conditions may not align with historical reference conditions in most ponderosa

  2. Satellite Image-based Estimates of Snow Water Equivalence in Restored Ponderosa Pine Forests in Northern Arizona

    Science.gov (United States)

    Sankey, T.; Springer, A. E.; O'Donnell, F. C.; Donald, J.; McVay, J.; Masek Lopez, S.

    2014-12-01

    The U.S. Forest Service plans to conduct forest restoration treatments through the Four Forest Restoration Initiative (4FRI) on hundreds of thousands of acres of ponderosa pine forest in northern Arizona over the next 20 years with the goals of reducing wildfire hazard and improving forest health. The 4FRI's key objective is to thin and burn the forests to create within-stand openings that "promote snowpack accumulation and retention which benefit groundwater recharge and watershed processes at the fine (1 to 10 acres) scale". However, little is known about how these openings created by restoration treatments affect snow water equivalence (SWE) and soil moisture, which are key parts of the water balance that greatly influence water availability for healthy trees and for downstream water users in the Sonoran Desert. We have examined forest canopy cover by calculating a Normalized Difference Vegetation Index (NDVI), a key indicator of green vegetation cover, using Landsat satellite data. We have then compared NDVI between treatments at our study sites in northern Arizona and have found statistically significant differences in tree canopy cover between treatments. The control units have significantly greater forest canopy cover than the treated units. The thinned units also have significantly greater tree canopy cover than the thin-and-burn units. Winter season Landsat images have also been analyzed to calculate Normalized Difference Snow Index (NDSI), a key indicator of snow water equivalence and snow accumulation at the treated and untreated forests. The NDSI values from these dates are examined to determine if snow accumulation and snow water equivalence vary between treatments at our study sites. NDSI is significantly greater at the treated units than the control units. In particular, the thinned forest units have significantly greater snow cover than the control units. Our results indicate that forest restoration treatments result in increased snow pack

  3. Artificial recharge of groundwater through sprinkling infiltration: impacts on forest soil and the nutrient status and growth of Scots pine.

    Science.gov (United States)

    Nöjd, Pekka; Lindroos, Antti-Jussi; Smolander, Aino; Derome, John; Lumme, Ilari; Helmisaari, Heljä-Sisko

    2009-05-01

    We studied the chemical changes in forest soil and the effects on Scots pine trees caused by continuous sprinkling infiltration over a period of two years, followed by a recovery period of two years. Infiltration increased the water input onto the forest soil by a factor of approximately 1000. After one year of infiltration, the pH of the organic layer had risen from about 4.0 to 6.7. The NH(4)-N concentration in the organic layer increased, most probably due to the NH(4) ions in the infiltration water, as the net N mineralization rate did not increase. Sprinkling infiltration initiated nitrification in the mineral soil. Macronutrient concentrations generally increased in the organic layer and mineral soil. An exception, however, was the concentration of extractable phosphorus, which decreased strongly during the infiltration period and did not show a recovery within two years. The NO(3)-N and K concentrations had reverted back to their initial level during the two-year recovery period, while the concentrations of Ca, Mg and NH(4)-N were still elevated. Nutrient concentrations in the pine needles increased on the infiltrated plots. However, the needle P concentration increased, despite the decrease in plant-available P in the soil. Despite the increase in the nutrient status, there were some visible signs of chlorosis in the current-year needles after two years of infiltration. The radial growth of the pines more than doubled on the infiltrated plots, which suggests that the very large increase in the water input onto the forest floor had no adverse effect on the functioning of the trees. However, a monitoring period of four years is not sufficient for detecting potential long term detrimental effects on forest trees.

  4. Extreme late-summer drought causes neutral annual carbon balance in southwestern ponderosa pine forests and grasslands

    International Nuclear Information System (INIS)

    Kolb, Thomas; Dore, Sabina; Montes-Helu, Mario

    2013-01-01

    We assessed the impacts of extreme late-summer drought on carbon balance in a semi-arid forest region in Arizona. To understand drought impacts over extremes of forest cover, we measured net ecosystem production (NEP), gross primary production (GPP), and total ecosystem respiration (TER) with eddy covariance over five years (2006–10) at an undisturbed ponderosa pine (Pinus ponderosa) forest and at a former forest converted to grassland by intense burning. Drought shifted annual NEP from a weak source of carbon to the atmosphere to a neutral carbon balance at the burned site and from a carbon sink to neutral at the undisturbed site. Carbon fluxes were particularly sensitive to drought in August. Drought shifted August NEP at the undisturbed site from sink to source because the reduction of GPP (70%) exceeded the reduction of TER (35%). At the burned site drought shifted August NEP from weak source to neutral because the reduction of TER (40%) exceeded the reduction of GPP (20%). These results show that the lack of forest recovery after burning and the exposure of undisturbed forests to late-summer drought reduce carbon sink strength and illustrate the high vulnerability of forest carbon sink strength in the southwest US to predicted increases in intense burning and precipitation variability. (letter)

  5. Extreme late-summer drought causes neutral annual carbon balance in southwestern ponderosa pine forests and grasslands

    Science.gov (United States)

    Kolb, Thomas; Dore, Sabina; Montes-Helu, Mario

    2013-03-01

    We assessed the impacts of extreme late-summer drought on carbon balance in a semi-arid forest region in Arizona. To understand drought impacts over extremes of forest cover, we measured net ecosystem production (NEP), gross primary production (GPP), and total ecosystem respiration (TER) with eddy covariance over five years (2006-10) at an undisturbed ponderosa pine (Pinus ponderosa) forest and at a former forest converted to grassland by intense burning. Drought shifted annual NEP from a weak source of carbon to the atmosphere to a neutral carbon balance at the burned site and from a carbon sink to neutral at the undisturbed site. Carbon fluxes were particularly sensitive to drought in August. Drought shifted August NEP at the undisturbed site from sink to source because the reduction of GPP (70%) exceeded the reduction of TER (35%). At the burned site drought shifted August NEP from weak source to neutral because the reduction of TER (40%) exceeded the reduction of GPP (20%). These results show that the lack of forest recovery after burning and the exposure of undisturbed forests to late-summer drought reduce carbon sink strength and illustrate the high vulnerability of forest carbon sink strength in the southwest US to predicted increases in intense burning and precipitation variability.

  6. Effects of wildfire on soil water repellency in pine and eucalypt forest in central Portugal

    Science.gov (United States)

    Faria, Sílvia; Eufemia Varela, María.; Keizer, Jan Jacob

    2010-05-01

    Soil water repellency is a naturally occurring phenomenon that can be intensified by soil heating during fires. Fire-induced or -enhanced water repellency, together with the loss of plant cover, is widely regarded as a key factor in increased surface runoff and accelerated erosion in recently burnt areas. The present study is part of the EROSFIRE-II project, whose main aim is to assess and predict post-wildfire hydrological and erosion processes at multiple spatial scales, ranging from micro-plot (Pinus pinaster and Eucaliptus globulus). In addition, two similar but long unburned slopes were selected in the immediate surroundings. For a period of 10 months, starting November 2008, water repellency and moisture content of the 0-5 cm topsoil layer were measured in the field at monthly intervals. Repellency was measured using the ‘Molarity of an Ethanol Droplet' (MED) test, soil moisture content using a DECAGON EC5 sensor. The results revealed a very strong repellency (ethanol classes 6-7) at all four sites during the first sampling period in November 2008, suggesting that the immediate wildfire effects were minor for both forest types. In the subsequent 5 to 6 months, however, there was a definite tendency for higher ethanol classes at the recently burnt than the adjacent unburned sites. Especially in the case of the pine stands, this tendency was inverted during the remaining months. The above-mentioned differences between the neighboring sites reflected more pronounced temporal patters in the case of the unburned sites, where median repellency levels corresponded none to slight severity ratings from December to March (pine) or April (eucalypt). Such seasonal drops in repellency were considerably shorter at the two burnt sites (1-2 months) and also less pronounced, without median ethanol classes becoming zero as occurred at the burnt sites. The seasonal repellency patterns at the unburned sites could be explained rather well by changes in soil moisture content

  7. Impact of mountain pine beetle induced mortality on forest carbon and water fluxes

    International Nuclear Information System (INIS)

    E Reed, David; Ewers, Brent E; Pendall, Elise

    2014-01-01

    Quantifying impacts of ecological disturbance on ecosystem carbon and water fluxes will improve predictive understanding of biosphere—atmosphere feedbacks. Tree mortality caused by mountain pine bark beetles (Dendroctonus ponderosae) is hypothesized to decrease photosynthesis and water flux to the atmosphere while increasing respiration at a rate proportional to mortality. This work uses data from an eddy-covariance flux tower in a bark beetle infested lodgepole pine (Pinus contorta) forest to test ecosystem responses during the outbreak. Analyses were conducted on components of carbon (C) and water fluxes in response to disturbance and environmental factors (solar radiation, soil water content and vapor pressure deficit). Maximum CO 2 uptake did not change as tree basal area mortality increased from 30 to 78% over three years of beetle disturbance. Growing season evapotranspiration varied among years while ecosystem water use efficiency (the ratio of net CO 2 uptake to water vapor loss) did not change. Between 2009 and 2011, canopy water conductance increased from 98.6 to 151.7 mmol H 2 O m −2 s −1 . Ecosystem light use efficiency of photosynthesis increased, with quantum yield increasing by 16% during the outbreak as light increased below the mature tree canopy and illuminated remaining vegetation more. Overall net ecosystem productivity was correlated with water flux and hence water availability. Average weekly ecosystem respiration, derived from light response curves and standard Ameriflux protocols for CO 2 flux partitioning into respiration and gross ecosystem productivity, did not change as mortality increased. Separate effects of increased respiration and photosynthesis efficiency largely canceled one another out, presumably due to increased diffuse light in the canopy and soil organic matter decomposition resulting in no change in net CO 2 exchange. These results agree with an emerging consensus in the literature demonstrating CO 2 and H 2 O dynamics

  8. Effects of Initial Stand Density and Climate on Red Pine Productivity within Huron National Forest, Michigan, USA

    Directory of Open Access Journals (Sweden)

    Joseph O'Brien

    2012-12-01

    Full Text Available Changes in climate are predicted to significantly affect the productivity of trees in the Great Lakes region over the next century. Forest management decisions, such as initial stand density, can promote climatic resiliency and moderate decreased productivity through the reduction of tree competition. The influences of climate (temperature and precipitation and forest management (initial stand density on the productivity of red pine (Pinus resinosa across multiple sites within Huron National Forest, Michigan, were examined using dendrochronological methods. Two common planting regimes were compared in this analysis; low initial density (1977 trees per hectare. Low initial density stands were found to have a higher climatic resilience by combining equal or greater measures of productivity, while having a reduced sensitivity to monthly and seasonal climate, particularly to summer drought.

  9. Litter and dead wood dynamics in ponderosa pine forests along a 160-year chronosequence.

    Science.gov (United States)

    Hall, S A; Burke, I C; Hobbs, N T

    2006-12-01

    Disturbances such as fire play a key role in controlling ecosystem structure. In fire-prone forests, organic detritus comprises a large pool of carbon and can control the frequency and intensity of fire. The ponderosa pine forests of the Colorado Front Range, USA, where fire has been suppressed for a century, provide an ideal system for studying the long-term dynamics of detrital pools. Our objectives were (1) to quantify the long-term temporal dynamics of detrital pools; and (2) to determine to what extent present stand structure, topography, and soils constrain these dynamics. We collected data on downed dead wood, litter, duff (partially decomposed litter on the forest floor), stand structure, topographic position, and soils for 31 sites along a 160-year chronosequence. We developed a compartment model and parameterized it to describe the temporal trends in the detrital pools. We then developed four sets of statistical models, quantifying the hypothesized relationship between pool size and (1) stand structure, (2) topography, (3) soils variables, and (4) time since fire. We contrasted how much support each hypothesis had in the data using Akaike's Information Criterion (AIC). Time since fire explained 39-80% of the variability in dead wood of different size classes. Pool size increased to a peak as material killed by the fire fell, then decomposed rapidly to a minimum (61-85 years after fire for the different pools). It then increased, presumably as new detritus was produced by the regenerating stand. Litter was most strongly related to canopy cover (r2 = 77%), suggesting that litter fall, rather than decomposition, controls its dynamics. The temporal dynamics of duff were the hardest to predict. Detrital pool sizes were more strongly related to time since fire than to environmental variables. Woody debris peak-to-minimum time was 46-67 years, overlapping the range of historical fire return intervals (1 to > 100 years). Fires may therefore have burned under a

  10. Liming with powdered oil-shale ash in a heavily damaged forest ecosystem. 1.The effect on forest soil in a pine stand

    International Nuclear Information System (INIS)

    Terasmaa, T.; Sepp, S.

    1994-01-01

    A fertilization and liming experiment with mineral fertilizers and powdered oil-shale ash was carried out in a heavily damaged 50-year-old Scots pine ecosystem in South Estonia. In Estonia, where electric power is produced mainly in big oil-shale-fired power plants, huge quantities of SO 2 are flying into the atmosphere through the chimneys of the plants. However, it is characteristic of Estonia that simultaneously with comparatively high SO 2 pollution the proton load has been quite low because of big amounts of alkali c ash emitted together with SO 2 into the atmosphere through the chimneys of the thermal power plants. Therefore, acid rains are not frequent in Estonia. Acid precipitation here is caused mainly by SO 2 released in the central part of Europe. In Estonia acid rains are most frequently registered in the southern area of the country. At times rains with pH values below 5.1 (even 4.0 and lower) have been registered there. This is also the region where quite severely damaged pine forests can be found. As a rule, these forests grow on acid sandy soils poor in nutrients and bases. The aim of the present study was to investigate the possibility of using oil shale ash as a liming agent in a forest ecosystem for protecting forest soils from acidification and, together with some mineral fertilizers, for improving the health of injured pine stands. In Estonia the most easily available liming agent is powdered oil-shale ash, which has been widely used as a lime fertilizer for agricultural crops but so far has not been tested for liming forests on mineral soils. The comparison of the present study with the liming experiments carried out with limestone in Finland shows that the effect of oil-shale ash treatment of acid sandy soils to raise pH values and to reduce other characteristics of soil acidity was more effective than limestone liming of mineral soils in Finnish forests. The present study demonstrates that powdered oil-shale ash is highly effective in short

  11. Nine years of irrigation cause vegetation and fine root shifts in a water-limited pine forest.

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    Claude Herzog

    Full Text Available Scots pines (Pinus sylvestris L. in the inner-Alpine dry valleys of Switzerland have suffered from increased mortality during the past decades, which has been caused by longer and more frequent dry periods. In addition, a proceeding replacement of Scots pines by pubescent oaks (Quercus pubescens Willd. has been observed. In 2003, an irrigation experiment was performed to track changes by reducing drought pressure on the natural pine forest. After nine years of irrigation, we observed major adaptations in the vegetation and shifts in Scots pine fine root abundance and structure. Irrigation permitted new plant species to assemble and promote canopy closure with a subsequent loss of herb and moss coverage. Fine root dry weight increased under irrigation and fine roots had a tendency to elongate. Structural composition of fine roots remained unaffected by irrigation, expressing preserved proportions of cellulose, lignin and phenolic substances. A shift to a more negative δ13C signal in the fine root C indicates an increased photosynthetic activity in irrigated pine trees. Using radiocarbon (14C measurement, a reduced mean age of the fine roots in irrigated plots was revealed. The reason for this is either an increase in newly produced fine roots, supported by the increase in fine root biomass, or a reduced lifespan of fine roots which corresponds to an enhanced turnover rate. Overall, the responses belowground to irrigation are less conspicuous than the more rapid adaptations aboveground. Lagged and conservative adaptations of tree roots with decadal lifespans are challenging to detect, hence demanding for long-term surveys. Investigations concerning fine root turnover rate and degradation processes under a changing climate are crucial for a complete understanding of C cycling.

  12. Phenology of the Pine Bark Adelgid, Pineus strobi (Hemiptera: Adelgidae), in White Pine Forests of Southwestern Virginia.

    Science.gov (United States)

    Wantuch, Holly A; Kuhar, Thomas P; Salom, Scott M

    2017-12-08

    The pine bark adelgid, Pineus strobi Hartig (Hemiptera: Adelgidae), is a native herbivore of eastern white pine, Pinus strobus L. (Pinales: Pinaceae), in eastern North America. P. strobi does not appear to have any dominant overwintering lifestage in southwest Virginia, as it does in its northern range. Eggs can be found consistently from late March through early December and may be produced sporadically later throughout the winter during warm periods. Two distinct generations were observed in the spring, after which life stage frequencies overlapped. Adult body size varied seasonally and was greatest in the spring. The present study constitutes the first recording of phenological details of the P. strobi in its southern range, informing biological control efforts aimed at closely related invasive pests. The phenological plasticity observed between northern and southern P. strobi populations provides insight into the potential effects of climate on the population dymanics of this and related species. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Liming with powdered oil-shale ash in a heavily damaged forest ecosystem. 2.The effect on forest condition in a pine stand

    International Nuclear Information System (INIS)

    Terasmaa, T.; Pikk, J.

    1995-01-01

    First years after the treatment (in 1987) of forest soil with mineral fertilizers and powdered oil-shale ash in a heavily damaged 50-year-old Scots pine ecosystem showed a comparatively small effect (B<0.95) of liming on the stand characters. However, in comparison with the effect of only NPK fertilization on the volume growth and the health state of trees, liming (NPK+oil-shale ash) tended to increase the positive influence of fertilizers. Under the influence of oil-shale ash the mortality of the trees was lower, the density of the stand rose more, and the mean radial increment of trees was by 26% greater than after the NPK treatment without a lime agent. On the whole, the effect of oil-shale ash liming on the growth and health condition of the pine stand was not high. However, the first results of its experimental use on mineral forest soil cannot serve as the basis for essential conclusions. Still, the results give us some assurance to continue our experimental work with powdered oil-shale ash in forests with the purpose of regulating the high acidity of forest soils in some sites to gain positive shifts in the forest life. Taking into account the low price of the powdered oil-shale ash and the plentiful resources of this liming material in Estonia, even a small trend towards an improvement of forest condition on poor sandy soils would be a satisfactory final result of the work. It is essential to note that oil-shale ash is not only a simple liming material, but also a lime fertilizer consisting of numerous chemical elements necessary for plant growth. 2 tabs., 3 figs., 18 refs

  14. Allozyme variation of bishop pine associated with pygmy forest soils in northern California

    Science.gov (United States)

    Constance I. Millar

    1989-01-01

    Two races of bishop pine (Pinus muricata D. Don) meet in a narrow contact zone near sea level along the Sonoma County coast, northern California. The races previously were identified by foliar ("blue" in north, "green" in south), monoterpene, and allozyme differences. Disjunct stands of blue bishop pine were observed at higher elevations along a...

  15. Entropy dynamics in cone production of longleaf pine forests in the southeastern United States

    Science.gov (United States)

    Xiongwen Chen; Dale G. Brockway; Qinfeng Guo

    2016-01-01

    Sporadic temporal patterns of seed production are a challenge for the regeneration and restoration of longleaf pine, which is a keystone component of an endangered ecosystem in the southeastern United States. In this study, long-term data for longleaf pine cone production, collected at six sites across the southeastern region, was examined from the perspective of...

  16. Longleaf pine ecosystem restoration: the role of the USDA Forest Service

    Science.gov (United States)

    Charles K. McMahon; D.J. Tomczak; R.M. Jeffers

    1998-01-01

    The greater longleaf pine ecosystem once occupied over 90 million acres from southeastern Virginia, south to central Florida, and west to eastern Texas. Today less than 3 million acres remain, with much of the remaining understory communities in an unhealthy state. A number of public and private conservation organizations are conducting collaborative longleaf pine...

  17. Spatial patterns of longleaf pine (Pinus palustris) seedling eastablishment on the croatan national forest, North Carolina

    Science.gov (United States)

    Chadwick R. Avery; Susan Cohen; Kathleen C. Parker; John S. Kush

    2004-01-01

    Ecological research aimed at determining optimal conditions for longleaf pine regeneration has become increasingly important in efforts @ restore the longleaf pine ecosystem. Numerous authors have concluded that a negative relationship exists between the occurrence of seedlings and the occurrence of mature trees; however, observed field conditions in several North...

  18. Reassessment of Loblolly Pine Decline on the Oakmulgee Ranger District, Talladega National Forest, Alabama

    Science.gov (United States)

    Nolan J. Hess; William J. Otroana; John P. Jones; Arthur J. Goddard; Charles H. Walkinshaw

    1999-01-01

    Loblolly pine (Pinus taeda L.) decline has been a management concern on the Oakmulgee Ranger District since the 1960's. The symptoms include sparse crowns, reduced radial growth, deterioration of fine roots, decline, and mortality of loblolly pine by age 50.

  19. Pruning dwarf mistletoe brooms reduces stress on Jeffrey pines, Cleveland National Forest, California

    Science.gov (United States)

    Robert F. Scharpf; Richard S. Smith; Detlev Vogler

    1987-01-01

    Western dwarf mistletoe (Arceuthobium campylopodum) is a damaging parasite of Jeffrey pines (Pinus jeffreyi) in southern California. Infected branches that develop into brooms are believed to reduce tlee vigor and increase mortality. Brooms were pruned from Jeffrey pines with varying levels of dwarf mistletoe infection and live...

  20. Effects of thinning intensities on soil infiltration and water storage capacity in a Chinese pine-oak mixed forest.

    Science.gov (United States)

    Chen, Lili; Yuan, Zhiyou; Shao, Hongbo; Wang, Dexiang; Mu, Xingmin

    2014-01-01

    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning): soil infiltration rate and water storage capacity of pine-oak mixed forest in Qinling Mountains. The soil initial infiltration rate, stable infiltration rate, and average infiltration rate in thinning 30% treatment were significantly increased by 21.1%, 104.6%, and 60.9%, compared with the control. The soil maximal water storage capacity and noncapillary water storage capacity in thinning 30% treatment were significantly improved by 20.1% and 34.3% in contrast to the control. The soil infiltration rate and water storage capacity were significantly higher in the surface layer (0~20 cm) than in the deep layers (20~40 cm and 40~60 cm). We found that the soil property was closely related to soil infiltration rate and water storage capacity.

  1. Effect of forest fragmentation on the epiphytic lichen cover of pine trunks on the example taiga town

    Directory of Open Access Journals (Sweden)

    Gaigysh Irina Sergeevna

    2012-06-01

    Full Text Available The main characteristics of epiphytic lichen cover on pine trunks depending on the area of natural pine forest in Kostomuksha (north Karelia were analysed. The town of Kostomuksha was built so that to provide the conservation of forest sites. 56 fragments with the area of 0.04 - 6.13 ha were studied. The average area of fragment is 0.62 ha, with 49 fragments (88% having the area less than 1 ha. Biodiversity and lichen cover were studied in the each fragment with using framework 10x20 cm. 1792 sample plots were made on 448 trees. The total lichens cover varies from 0 to 85%,averaging 10%. 25 species of lichens were found. The number of species in the sample plots varies from 0 to 9. Dominant species found are Hypogymnia physodes, Parmeliopsis ambigua, P. hyperopta, Imshaugia aleurites, Cladonia. Species Alectoria sarmentosa, Cladonia macilenta, Pseudevernia fufruraceae, Bryoria fremontii were less common. It was shown that the main parameters of lichen cover are closely related to the size of the area left in the city forest fragments. The maximum values of species diversity and cover of lichens were found in the fragments of more 1-2 hectares.

  2. Growth and structure of a young Aleppo pine planted forest after thinning for diversification and wildfire prevention

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Mirazo, J.; Gonzalez-Rebollar, J. L.

    2013-05-01

    Aim of study: In the Mediterranean, low timber-production forests are frequently thinned to promote biodiversity and reduce wildfire risk, but few studies in the region have addressed such goals. The aim of this research was to compare six thinning regimes applied to create a fuel break in a young Aleppo pine (Pinus halepensis Mill.) planted forest. Area of study: A semiarid continental high plateau in south-eastern Spain. Material and Methods: Three thinning intensities (Light, Medium and Heavy) were combined with two thinning methods: i) Random (tree selection), and ii) Regular (tree spacing). Tree growth and stand structure measurements were made four years following treatments. Main results: Heavy Random thinning successfully transformed the regular tree plantation pattern into a close-to-random spatial tree distribution. Heavy Regular thinning (followed by the Medium Regular and Heavy Random regimes) significantly reduced growth in stand basal area and biomass. Individual tree growth, in contrast, was greater in Heavy and Medium thinnings than in Light ones, which were similar to the Control. Research highlights: Heavy Random thinning seemed the most appropriate in a young Aleppo pine planted forest to reduce fire risk and artificial tree distribution simultaneously. Light Regular thinning avoids under stocking the stand and may be the most suitable treatment for creating a fuel break when the undergrowth poses a high fire risk. (Author) 35 refs.

  3. Dynamic equilibrium of radiocesium with stable cesium within the soil-mushroom system in Turkish pine forest

    International Nuclear Information System (INIS)

    Karadeniz, Ozlem; Yaprak, Guenseli

    2007-01-01

    Mushrooms and soils collected from pine forests in Izmir, Turkey were measured for radiocesium and stable Cs in 2002. The ranges of 137 Cs and stable Cs concentrations in mushrooms were 9.84 ± 1.67 to 401 ± 3.85 Bq kg -1 dry weight and 0.040 ± 0.004 to 11.3 ± 1.09 mg kg -1 dry weight, respectively. The concentrations of 137 Cs and stable Cs in soils were 0.29 ± 0.18 to 161 ± 1.12 Bq kg -1 dry weight and 0.14 ± 0.004 to 1.44 ± 0.045 mg kg -1 dry weight, respectively. Even though different species were included, the concentration ratios of 137 Cs to stable Cs were fairly constant for samples collected at the same forest site, and were in the same order of magnitude as the 137 Cs to stable Cs ratios for the organic soil layers. The soil-to-mushroom transfer factors of 137 Cs and stable Cs were in the range of 0.19-3.15 and 0.17-12.3, respectively. The transfer factors of 137 Cs were significantly correlated to those of stable Cs. - The 137 Cs/ 133 Cs ratios observed in mushroom samples and in organic layers shows that 137 Cs is well mixed with stable Cs within the biological cycle in the studied pine forest

  4. [Effects of selective cutting on the carbon density and net primary productivity of a mixed broadleaved-Korean pine forest in Northeast China].

    Science.gov (United States)

    Liu, Qi; Cai, Hui-Ying; Jin, Guang-Ze

    2013-10-01

    To accurately quantify forest carbon density and net primary productivity (NPP) is of great significance in estimating the role of forest ecosystems in global carbon cycle. By using the forest inventory and allometry approaches, this paper measured the carbon density and NPP of the virgin broadleaved-Korean pine (Pinus koraiensis) forest and of the broadleaved-Korean pine forest after 34 years selective-cutting (the cutting intensity was 30%, and the cutting trees were in large diameter class). The total carbon density of the virgin and selective-cutting broadleaved-Korean pine forests was (397.95 +/- 93.82) and (355.61 +/- 59.37) t C x hm(-2), respectively. In the virgin forest, the carbon density of the vegetation, debris, and soil accounted for 31.0%, 3.1%, and 65.9% of the total carbon pool, respectively; in the selective-cutting forest, the corresponding values were 31.7%, 2.9%, and 65.4%, respectively. No significant differences were observed in the total carbon density and the carbon density of each component between the two forests. The total NPP of the virgin and selective-cutting forests was (36.27 +/- 0.36) and (6.35 +/- 0.70) t C x hm(-2) x a(-1), among which, the NPP of overstory, understory, and fine roots in virgin forest and selective-cutting forest accounted for 60.3%, 2.0%, and 37.7%, and 66.1%, 2.0%, and 31.2%, respectively. No significant differences were observed in the total NPP and the contribution rate of each component between the two forests. However, the ratios of the needle and broadleaf NPPs of the virgin and selective-cutting forests were 47.24:52.76 and 20.48:79.52, respectively, with a significant difference. The results indicated that the carbon density and NPP of the broadleaved-Korean pine forest after 34 years selective-cutting recovered to the levels of the virgin broadleaved-Korean pine forest.

  5. Areas of Agreement and Disagreement Regarding Ponderosa Pine and Mixed Conifer Forest Fire Regimes: A Dialogue with Stevens et al.

    Directory of Open Access Journals (Sweden)

    Dennis C Odion

    Full Text Available In a recent PLOS ONE paper, we conducted an evidence-based analysis of current versus historical fire regimes and concluded that traditionally defined reference conditions of low-severity fire regimes for ponderosa pine (Pinus ponderosa and mixed-conifer forests were incomplete, missing considerable variability in forest structure and fire regimes. Stevens et al. (this issue agree that high-severity fire was a component of these forests, but disagree that one of the several sources of evidence, stand age from a large number of forest inventory and analysis (FIA plots across the western USA, support our findings that severe fire played more than a minor role ecologically in these forests. Here we highlight areas of agreement and disagreement about past fire, and analyze the methods Stevens et al. used to assess the FIA stand-age data. We found a major problem with a calculation they used to conclude that the FIA data were not useful for evaluating fire regimes. Their calculation, as well as a narrowing of the definition of high-severity fire from the one we used, leads to a large underestimate of conditions consistent with historical high-severity fire. The FIA stand age data do have limitations but they are consistent with other landscape-inference data sources in supporting a broader paradigm about historical variability of fire in ponderosa and mixed-conifer forests than had been traditionally recognized, as described in our previous PLOS paper.

  6. Areas of Agreement and Disagreement Regarding Ponderosa Pine and Mixed Conifer Forest Fire Regimes: A Dialogue with Stevens et al.

    Science.gov (United States)

    Odion, Dennis C; Hanson, Chad T; Baker, William L; DellaSala, Dominick A; Williams, Mark A

    2016-01-01

    In a recent PLOS ONE paper, we conducted an evidence-based analysis of current versus historical fire regimes and concluded that traditionally defined reference conditions of low-severity fire regimes for ponderosa pine (Pinus ponderosa) and mixed-conifer forests were incomplete, missing considerable variability in forest structure and fire regimes. Stevens et al. (this issue) agree that high-severity fire was a component of these forests, but disagree that one of the several sources of evidence, stand age from a large number of forest inventory and analysis (FIA) plots across the western USA, support our findings that severe fire played more than a minor role ecologically in these forests. Here we highlight areas of agreement and disagreement about past fire, and analyze the methods Stevens et al. used to assess the FIA stand-age data. We found a major problem with a calculation they used to conclude that the FIA data were not useful for evaluating fire regimes. Their calculation, as well as a narrowing of the definition of high-severity fire from the one we used, leads to a large underestimate of conditions consistent with historical high-severity fire. The FIA stand age data do have limitations but they are consistent with other landscape-inference data sources in supporting a broader paradigm about historical variability of fire in ponderosa and mixed-conifer forests than had been traditionally recognized, as described in our previous PLOS paper.

  7. Investigation of radiocesium in fungi in a Danish Scotch pine forest ecosystem

    International Nuclear Information System (INIS)

    Strandberg, M.

    1992-01-01

    During the autumn of 1991 a boreal Scotch pine forest, Tisvilde Hegn, was investigated with respect to the ratio 137 Cs fungi / 137 Cs soil m 2 /kg in the occurring fungi. Observed Ratios (OR) (fungi/soil) m 2 /kg were determined Totally (TOR), for Chernobyl cesium (COR), Fallout cesium totally (FOR tot ) and Fallout cesium in the upper 5 cm of soil (FOR 0-5 ) separately. The soil is sand under an approximately 5 cm thick layer of organic soil, the clay content is very low, between 0 and 2%. Cesium from Chernobyl is still totally in the upper 5 cm's, while almost half of the fallout cesium has penetrated to depths lower than 5 cm's. In the soil and litter there are 923 Bq 137 Cs deriving from Chernobyl and 2212 Bq 137 Cs deriving from weapon testing in the fifties and sixties. Observed Ratios (OR) BqCs-137/kgd.m. fungi/soil were measured in a number of fungi. In the fungi TOR varied between 0 and 6.6 m 2 /kg, though generally it was between 0.2 and 1.3 m 2 /kg. COR varied between 0 and 10.9 m 2 /kg with a general variation between 0.3 and 3.3 m 2 /kg. FOR tot varied between 0 and 5 m 2 /kg with a general variation between 0.1 and 0.9 m 2 /kg. FOR 0-5 varied between 0 and 8.5 m 2 /kg with a general variation between 0.2 and 1.5 m 2 /kg. Although there is exceptions, e.g Tricholoma portentosum, the general trend is that the Observed Ratio of the Chernobyl cesium is the highest, generally 50-200% higher than the OR of the fallout cesium in the upper 5 cm. (au) (10 refs.)

  8. Southern Pine Beetle Information System (SPBIS)

    Science.gov (United States)

    Valli Peacher

    2011-01-01

    The southern pine beetle (SPB) is the most destructive forest insect in the South. The SPB attacks all species of southern pine, but loblolly and shortleaf are most susceptible. The Southern Pine Beetle Information System (SPBIS) is the computerized database used by the national forests in the Southern Region for tracking individual southern pine beetle infestations....

  9. Relationships between net photosynthesis and foliar nitrogen concentrations in a loblobby pine forest ecosystem grown in elevated atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    Springer, C. J.; Thomas, R. B.; Delucia, E. H.

    2005-01-01

    The effects of elevated carbon dioxide concentration on the relationship between light-saturated net photosynthesis and area-based foliar nitrogen concentration in the canopy of a loblobby pine forest at the Duke Forest FACE experiment was examined. Two overstory and four understory tree species were examined at their growth carbon dioxide concentrations during the early summer and late summer of 1999, 2001 and 2002. Light-saturated net photosynthesis and foliar nitrogen relationship were compared to determine if the stimulatory effects of elevated carbon dioxide on net photosynthesis had declined. Results at all three sample times showed no difference in either the slopes, or in the y-intercepts of the net photosynthesis-foliar nitrogen relationship when measured at common carbon dioxide concentrations. Net photosynthesis was also unaffected by growth in elevated carbon dioxide, indicating that these overstory and understory trees continued to show strong stimulation of photosynthesis by elevated carbon dioxide. 46 refs., 6 tabs., 3 figs

  10. Long-Term Studies of Prescribed Burning in Loblolly Pine Forests of the Southeastern Coastal Plain

    Science.gov (United States)

    Thomas A. Waldrop; David H. van Lear; F. Thomas Lloyd; William R. Harms

    1987-01-01

    Prescribed fire provides many benefits in southern pine A study begun in 1946 provides a unique opportunity stands. to observe long-term changes in understory vegetation, soil properties, and overstory tree growth caused by repeated burning.

  11. Carbon and nitrogen accumulation in forest floor and surface soil under different geographic origins of Maritime pine (Pinus pinaster Aiton.) plantations

    Energy Technology Data Exchange (ETDEWEB)

    Ozdemir, E.; Oral, H. V.; Akburak, S.; Makineci, E.; Yilmaz, E.

    2013-09-01

    Aim of study: To determine if plantations consisting of different geographic origins of the Maritime pine (Pinus pinaster Aiton.) could have altered C and N stocks in the forest floor and surface soils. Area of study: Forest floor and mineral soil C and N stocks were measured in four adjacent plantations of different geographic origins of Maritime pine (Gironde, Toulon, Corsica and Spain) and adjacent primary native Sessile oak (Quercus petraea L.) at Burunsuz region in Belgrad Forest where is located in the Istanbul province in the Marmara geographical region between 41° 09’-41° 12’ N latitude and 28° 54’-29° 00’ E longitude in Turkey. Material and methods: Plots were compared as common garden experiments without replications. 15 surface soil (0-10 cm) and 15 forest floor samples were taken from each Maritime pine origins and adjacent native Sessile oak forest. C and N contents were determined on LECO Truspec 2000 CN analyzer. The statistical significance of the results was evaluated by one-way Analysis of Variance (ANOVA). Research highlights: Forest floor carbon mass, nitrogen concentration and nitrogen mass of forest floor showed a significant difference among origins. Soil carbon mass and nitrogen mass did not significantly differ among investigated plots. (Author)

  12. Carbon and nitrogen accumulation in forest floor and surface soil under different geographic origins of Maritime pine (Pinus pinaster Aiton. plantations

    Directory of Open Access Journals (Sweden)

    E. Ozdemir

    2013-07-01

    Full Text Available Aim of study : To determine if plantations consisting of different geographic origins of the Maritime pine (Pinus pinaster Aiton. could have altered C and N stocks in the forest floor and surface soils.Area of study : Forest floor and mineral soil C and N stocks were measured in four adjacent plantations of different geographic origins of Maritime pine (Gironde, Toulon, Corsica and Spain and adjacent primary native Sessile oak (Quercus petraea L. at Burunsuz region in Belgrad Forest where is located in the Istanbul province in the Marmara geographical region between 41°09' -41°12' N latitude and 28°54' - 29°00' E longitude in Turkey.Material and Methods : Plots were compared as common garden experiments without replications. 15 surface soil (0-10 cm and 15 forest floor samples were taken from each Maritime pine origins and adjacent native Sessile oak forest. C and N contents were determined on LECO Truspec 2000 CN analyzer. The statistical significance of the results was evaluated by one-way Analysis of Variance (ANOVA.Research highlights : Forest floor carbon mass, nitrogen concentration and nitrogen mass of forest floor showed a significant difference among origins. Soil carbon mass and nitrogen mass did not significantly differ among investigated plots.Keywords: carbon sequestration; C/N ratio; decomposition; exotic; tree provenance.

  13. Assessing the Defoliation of Pine Forests in a Long Time-Series and Spatiotemporal Prediction of the Defoliation Using Landsat Data

    Directory of Open Access Journals (Sweden)

    Chenghao Zhu

    2018-02-01

    Full Text Available Pine forests (Pinus tabulaeformis have been in danger of defoliation by a caterpillar in the west Liaoning province of China for more than thirty years. This paper aims to assess and predict the degree of damage to pine forests by using remote sensing and ancillary data. Through regression analysis of the pine foliage remaining ratios of field plots with several vegetation indexes of Landsat data, a feasible inversion model was obtained to detect the degree of damage using the Normalized Difference Infrared Index of 5th band (NDII5. After comparing the inversion result of the degree of damage to the pine in 29 years and the historical damage record, quantized results of damage assessment in a long time-series were accurately obtained. Based on the correlation analysis between meteorological variables and the degree of damage from 1984 to 2015, the average degree of damage was predicted in temporal scale. By adding topographic and other variables, a linear prediction model in spatiotemporal scale was constructed. The spatiotemporal model was based on 5015 public pine points for 24 years and reached 0.6169 in the correlation coefficient. This paper provided a feasible and quantitative method in the spatiotemporal prediction of forest pest occurrence by remote sensing.

  14. Seasonal Pattern of Decomposition and N, P, and C Dynamics in Leaf litter in a Mongolian Oak Forest and a Korean Pine Plantation

    Directory of Open Access Journals (Sweden)

    Jaeeun Sohng

    2014-10-01

    Full Text Available Distinct seasons and diverse tree species characterize temperate deciduous forests in NE Asia, but large areas of deciduous forests have been converted to conifer plantations. This study was conducted to understand the effects of seasons and tree species on leaf litter decomposition in a temperate forest. Using the litterbag method, the decomposition rate and nitrogen, phosphorous, and carbon dynamics of Mongolian oak (Quercus mongolica, Korean pine (Pinus koraiensis, and their mixed leaf litter were compared for 24 months in a Mongolian oak stand, an adjacent Korean pine plantation, and a Mongolian oak—Korean pine mixed stand. The decomposition rates of all the leaf litter types followed a pattern of distinct seasonal changes: most leaf litter decomposition occurred during the summer. Tree species was less influential on the leaf litter decomposition. The decomposition rates among different leaf litter types within the same stand were not significantly different, indicating no mixed litter effect. The immobilization of leaf litter N and P lasted for 14 months. Mongolian oak leaf litter and Korean pine leaf litter showed different N and P contents and dynamics during the decomposition, and soil P2O5 was highest in the Korean pine plantation, suggesting effects of plantation on soil nutrient budget.

  15. In situ secondary organic aerosol formation from ambient pine forest air using an oxidation flow reactor

    Science.gov (United States)

    Palm, Brett B.; Campuzano-Jost, Pedro; Ortega, Amber M.; Day, Douglas A.; Kaser, Lisa; Jud, Werner; Karl, Thomas; Hansel, Armin; Hunter, James F.; Cross, Eben S.; Kroll, Jesse H.; Peng, Zhe; Brune, William H.; Jimenez, Jose L.

    2016-03-01

    An oxidation flow reactor (OFR) is a vessel inside which the concentration of a chosen oxidant can be increased for the purpose of studying SOA formation and aging by that oxidant. During the BEACHON-RoMBAS (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen-Rocky Mountain Biogenic Aerosol Study) field campaign, ambient pine forest air was oxidized by OH radicals in an OFR to measure the amount of SOA that could be formed from the real mix of ambient SOA precursor gases, and how that amount changed with time as precursors changed. High OH concentrations and short residence times allowed for semicontinuous cycling through a large range of OH exposures ranging from hours to weeks of equivalent (eq.) atmospheric aging. A simple model is derived and used to account for the relative timescales of condensation of low-volatility organic compounds (LVOCs) onto particles; condensational loss to the walls; and further reaction to produce volatile, non-condensing fragmentation products. More SOA production was observed in the OFR at nighttime (average 3 µg m-3 when LVOC fate corrected) compared to daytime (average 0.9 µg m-3 when LVOC fate corrected), with maximum formation observed at 0.4-1.5 eq. days of photochemical aging. SOA formation followed a similar diurnal pattern to monoterpenes, sesquiterpenes, and toluene+p-cymene concentrations, including a substantial increase just after sunrise at 07:00 local time. Higher photochemical aging (> 10 eq. days) led to a decrease in new SOA formation and a loss of preexisting OA due to heterogeneous oxidation followed by fragmentation and volatilization. When comparing two different commonly used methods of OH production in OFRs (OFR185 and OFR254-70), similar amounts of SOA formation were observed. We recommend the OFR185 mode for future forest studies. Concurrent gas-phase measurements of air after OH oxidation illustrate the decay of primary VOCs, production of small oxidized organic

  16. In situ secondary organic aerosol formation from ambient pine forest air using an oxidation flow reactor

    Directory of Open Access Journals (Sweden)

    B. B. Palm

    2016-03-01

    Full Text Available An oxidation flow reactor (OFR is a vessel inside which the concentration of a chosen oxidant can be increased for the purpose of studying SOA formation and aging by that oxidant. During the BEACHON-RoMBAS (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen–Rocky Mountain Biogenic Aerosol Study field campaign, ambient pine forest air was oxidized by OH radicals in an OFR to measure the amount of SOA that could be formed from the real mix of ambient SOA precursor gases, and how that amount changed with time as precursors changed. High OH concentrations and short residence times allowed for semicontinuous cycling through a large range of OH exposures ranging from hours to weeks of equivalent (eq. atmospheric aging. A simple model is derived and used to account for the relative timescales of condensation of low-volatility organic compounds (LVOCs onto particles; condensational loss to the walls; and further reaction to produce volatile, non-condensing fragmentation products. More SOA production was observed in the OFR at nighttime (average 3 µg m−3 when LVOC fate corrected compared to daytime (average 0.9 µg m−3 when LVOC fate corrected, with maximum formation observed at 0.4–1.5 eq. days of photochemical aging. SOA formation followed a similar diurnal pattern to monoterpenes, sesquiterpenes, and toluene+p-cymene concentrations, including a substantial increase just after sunrise at 07:00 local time. Higher photochemical aging (> 10 eq. days led to a decrease in new SOA formation and a loss of preexisting OA due to heterogeneous oxidation followed by fragmentation and volatilization. When comparing two different commonly used methods of OH production in OFRs (OFR185 and OFR254-70, similar amounts of SOA formation were observed. We recommend the OFR185 mode for future forest studies. Concurrent gas-phase measurements of air after OH oxidation illustrate the decay of primary VOCs, production

  17. De novo assembly of maritime pine transcriptome: implications for forest breeding and biotechnology.

    Science.gov (United States)

    Canales, Javier; Bautista, Rocio; Label, Philippe; Gómez-Maldonado, Josefa; Lesur, Isabelle; Fernández-Pozo, Noe; Rueda-López, Marina; Guerrero-Fernández, Dario; Castro-Rodríguez, Vanessa; Benzekri, Hicham; Cañas, Rafael A; Guevara, María-Angeles; Rodrigues, Andreia; Seoane, Pedro; Teyssier, Caroline; Morel, Alexandre; Ehrenmann, François; Le Provost, Grégoire; Lalanne, Céline; Noirot, Céline; Klopp, Christophe; Reymond, Isabelle; García-Gutiérrez, Angel; Trontin, Jean-François; Lelu-Walter, Marie-Anne; Miguel, Celia; Cervera, María Teresa; Cantón, Francisco R; Plomion, Christophe; Harvengt, Luc; Avila, Concepción; Gonzalo Claros, M; Cánovas, Francisco M

    2014-04-01

    Maritime pine (Pinus pinasterAit.) is a widely distributed conifer species in Southwestern Europe and one of the most advanced models for conifer research. In the current work, comprehensive characterization of the maritime pine transcriptome was performed using a combination of two different next-generation sequencing platforms, 454 and Illumina. De novo assembly of the transcriptome provided a catalogue of 26 020 unique transcripts in maritime pine trees and a collection of 9641 full-length cDNAs. Quality of the transcriptome assembly was validated by RT-PCR amplification of selected transcripts for structural and regulatory genes. Transcription factors and enzyme-encoding transcripts were annotated. Furthermore, the available sequencing data permitted the identification of polymorphisms and the establishment of robust single nucleotide polymorphism (SNP) and simple-sequence repeat (SSR) databases for genotyping applications and integration of translational genomics in maritime pine breeding programmes. All our data are freely available at SustainpineDB, the P. pinaster expressional database. Results reported here on the maritime pine transcriptome represent a valuable resource for future basic and applied studies on this ecological and economically important pine species. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  18. Late Holocene geomorphic record of fire in ponderosa pine and mixed-conifer forests, Kendrick Mountain, northern Arizona, USA

    Science.gov (United States)

    Jenkins, S.E.; Hull, Sieg C.; Anderson, D.E.; Kaufman, D.S.; Pearthree, P.A.

    2011-01-01

    Long-term fire history reconstructions enhance our understanding of fire behaviour and associated geomorphic hazards in forested ecosystems. We used 14C ages on charcoal from fire-induced debris-flow deposits to date prehistoric fires on Kendrick Mountain, northern Arizona, USA. Fire-related debris-flow sedimentation dominates Holocene fan deposition in the study area. Radiocarbon ages indicate that stand-replacing fire has been an important phenomenon in late Holocene ponderosa pine (Pinus ponderosa) and ponderosa pine-mixed conifer forests on steep slopes. Fires have occurred on centennial scales during this period, although temporal hiatuses between recorded fires vary widely and appear to have decreased during the past 2000 years. Steep slopes and complex terrain may be responsible for localised crown fire behaviour through preheating by vertical fuel arrangement and accumulation of excessive fuels. Holocene wildfire-induced debris flow events occurred without a clear relationship to regional climatic shifts (decadal to millennial), suggesting that interannual moisture variability may determine fire year. Fire-debris flow sequences are recorded when (1) sufficient time has passed (centuries) to accumulate fuels; and (2) stored sediment is available to support debris flows. The frequency of reconstructed debris flows should be considered a minimum for severe events in the study area, as fuel production may outpace sediment storage. ?? IAWF 2011.

  19. Examining fire-induced forest changes using novel remote sensing technique: a case study in a mixed pine-oak forest

    Science.gov (United States)

    Meng, R.; Wu, J.; Zhao, F. R.; Cook, B.; Hanavan, R. P.; Serbin, S.

    2017-12-01

    Fire-induced forest changes has long been a central focus for forest ecology and global carbon cycling studies, and is becoming a pressing issue for global change biologists particularly with the projected increases in the frequency and intensity of fire with a warmer and drier climate. Compared with time-consuming and labor intensive field-based approaches, remote sensing offers a promising way to efficiently assess fire effects and monitor post-fire forest responses across a range of spatial and temporal scales. However, traditional remote sensing studies relying on simple optical spectral indices or coarse resolution imagery still face a number of technical challenges, including confusion or contamination of the signal by understory dynamics and mixed pixels with moderate to coarse resolution data (>= 30 m). As such, traditional remote sensing may not meet the increasing demand for more ecologically-meaningful monitoring and quantitation of fire-induced forest changes. Here we examined the use of novel remote sensing technique (i.e. airborne imaging spectroscopy and LiDAR measurement, very high spatial resolution (VHR) space-borne multi-spectral measurement, and high temporal-spatial resolution UAS-based (Unmanned Aerial System) imagery), in combination with field and phenocam measurements to map forest burn severity across spatial scales, quantify crown-scale post-fire forest recovery rate, and track fire-induced phenology changes in the burned areas. We focused on a mixed pine-oak forest undergoing multiple fire disturbances for the past several years in Long Island, NY as a case study. We demonstrate that (1) forest burn severity mapping from VHR remote sensing measurement can capture crown-scale heterogeneous fire patterns over large-scale; (2) the combination of VHR optical and structural measurements provides an efficient means to remotely sense species-level post-fire forest responses; (3) the UAS-based remote sensing enables monitoring of fire

  20. Seasonal dynamics of Boletus edulis and Lactarius deliciosus extraradical mycelium in pine forests of central Spain.

    Science.gov (United States)

    De la Varga, Herminia; Águeda, Beatriz; Ágreda, Teresa; Martínez-Peña, Fernando; Parladé, Javier; Pera, Joan

    2013-07-01

    The annual belowground dynamics of extraradical soil mycelium and sporocarp production of two ectomycorrhizal fungi, Boletus edulis and Lactarius deliciosus, have been studied in two different pine forests (Pinar Grande and Pinares Llanos, respectively) in Soria (central Spain). Soil samples (five per plot) were taken monthly (from September 2009 to August 2010 in Pinar Grande and from September 2010 to September 2011 in Pinares Llanos) in eight permanent plots (four for each site). B. edulis and L. deliciosus extraradical soil mycelium was quantified by real-time polymerase chain reaction, with DNA extracted from soil samples, using specific primers and TaqMan® probes. The quantities of B. edulis soil mycelium did not differ significantly between plots, but there was a significant difference over time with a maximum in February (0.1576 mg mycelium/g soil) and a minimum in October (0.0170 mg mycelium/g soil). For L. deliciosus, significant differences were detected between plots and over time. The highest amount of mycelium was found in December (1.84 mg mycelium/g soil) and the minimum in February (0.0332 mg mycelium/g soil). B. edulis mycelium quantities were positively correlated with precipitation of the current month and negatively correlated with the mean temperature of the previous month. Mycelium biomass of L. deliciosus was positively correlated with relative humidity and negatively correlated with mean temperature and radiation. No significant correlation between productivity of the plots with the soil mycelium biomass was observed for any of the two species. No correlations were found between B. edulis sporocarp production and weather parameters. Sporocarp production of L. deliciosus was positively correlated with precipitation and relative humidity and negatively correlated with maximum and minimum temperatures. Both species have similar distribution over time, presenting an annual dynamics characterized by a seasonal variability, with a clear increase

  1. Comparison of different real time VOC measurement techniques in a ponderosa pine forest

    Directory of Open Access Journals (Sweden)

    L. Kaser

    2013-03-01

    Full Text Available Volatile organic compound (VOC mixing ratios measured by five independent instruments are compared at a forested site dominated by ponderosa pine (Pinus Ponderosa during the BEACHON-ROCS field study in summer 2010. The instruments included a Proton Transfer Reaction Time of Flight Mass Spectrometer (PTR-TOF-MS, a Proton Transfer Reaction Quadrupole Mass Spectrometer (PTR-MS, a Fast Online Gas-Chromatograph coupled to a Mass Spectrometer (GC/MS; TOGA, a Thermal Dissociation Chemical Ionization Mass Spectrometer (PAN-CIMS and a Fiber Laser-Induced Fluorescence Instrument (FILIF. The species discussed in this comparison include the most important biogenic VOCs and a selected suite of oxygenated VOCs that are thought to dominate the VOC reactivity at this particular site as well as typical anthropogenic VOCs that showed low mixing ratios at this site. Good agreement was observed for methanol, the sum of the oxygenated hemiterpene 2-methyl-3-buten-2-ol (MBO and the hemiterpene isoprene, acetaldehyde, the sum of acetone and propanal, benzene and the sum of methyl ethyl ketone (MEK and butanal. Measurements of the above VOCs conducted by different instruments agree within 20%. The ability to differentiate the presence of toluene and cymene by PTR-TOF-MS is tested based on a comparison with GC-MS measurements, suggesting a study-average relative contribution of 74% for toluene and 26% for cymene. Similarly, 2-hydroxy-2-methylpropanal (HMPR is found to interfere with the sum of methyl vinyl ketone and methacrolein (MVK + MAC using PTR-(TOF-MS at this site. A study-average relative contribution of 85% for MVK + MAC and 15% for HMPR was determined. The sum of monoterpenes measured by PTR-MS and PTR-TOF-MS was generally 20–25% higher than the sum of speciated monoterpenes measured by TOGA, which included α-pinene, β-pinene, camphene, carene, myrcene, limonene, cineole as well as other terpenes. However, this difference is consistent throughout the study

  2. CONTRIBUTION FOR THE DIAGNOSIS AND CONTROL OF THE BARK BEETLES OF GENUS IPS (COLEOPTERA: SCOLYTIDAE) IN THE PINE FOREST OF CUBA

    OpenAIRE

    René Alberto López Castilla; Fidel Góngora Rojas; Celia Guerra Rivero; Enrique de Zayas Izaguirre; Antonio Fernández Vera; Natividad Triguero Isasi

    2009-01-01

    There are four pines species endemic from Cuba with width importance, from the Conservation of the Forest Genetic Resources at regional level to the mitigation of the climatic change. Their economical importance is due to forming pure forest stand of fast growth and of straight trunk. The bark beetle of the genus Ips De Geer (Coleoptera: Scolytidae) and the associate mushrooms from the complex Ophiostomatoid (Ceratocystidaceae: Microascales Phylum Ascomycotina) are those that cause the bigge...

  3. Post-fire diversity and abundance in pine and eucalipt stands in Portugal: effects of biogeography, topography, forest type and post-fire management

    OpenAIRE

    Maia, P.; Keizer, J.; Vasques, A.; Abrantes, N.; Roxo, L.; Fernandes, P.; Ferreira, A.; Moreira, F.

    2014-01-01

    This study concerned the mid-term regeneration of the woody understory vegetation of pure and mixed stands of Pinus pinaster Ait. and Eucalyptus globulus Labill. in northern and central Portugal following wildfires in 2005 and 2006. Pine and eucalypt stands are the most widespread and most fire-prone forest types in Portugal. The main aim was to investigate the importance of biogeography, topography, forest type and post-fire management operations in explaining the patterns in shr...

  4. Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre Occidental, Mexico

    NARCIS (Netherlands)

    Lammertink, J.M.; Rojas-Tomé, J.A.; Casillas-Orona, F.M.; Otto, R.L.

    1996-01-01

    The pine-oak forests of the Sierra Madre Occidental, a mountain range in NW Mexico, have recently been recognized as an area of high endemism and biodiversity. Selective logging threatens three bird species endemic to this habitat, who depend on standing dead trees (snags). This report is based on

  5. Remnant large 'rescue' trees enhance epiphyte resilience to anthropogenic disturbance of pine-oak forests in the Highlands of Chiapas, Mexico

    NARCIS (Netherlands)

    Wolf, J.H.D.

    2006-01-01

    I studied vascular epiphytes in 16 pine-oak forest fragments within an 400 km2 relatively flat area at c. 2300 m elevation on an extended gradient of anthropogenic disturbance. Epiphyte biomass and species richness on 35 oak host trees in six diameter classes varied between the sites from 0.8 to 243

  6. Why Mountain Pine Beetle Exacerbates a Principal-agent Relationship: Exploring Strategic Policy Responses to Beetle Attack in a Mixed Species Forest

    NARCIS (Netherlands)

    Bogle, T.; Kooten, van G.C.

    2012-01-01

    The management of public forestland is often carried out by private forest companies, in which case the landowner needs to exercise care in dealing with catastrophic natural disturbance. We use the mountain pine beetle (Dendroctonus ponderosae Hopkins, 1902) damage in British Columbia to explore how

  7. Stand restoration burning in oak-pine forests in the southern Applachians: effects on aboveground biomass and carbon and nitrogen cycling

    Science.gov (United States)

    Robert M. Hubbard; James M. Vose; Barton D. Clinton; Katherine J. Elliott; Jennifer D. Knoepp

    2004-01-01

    Understory prescribed burning is being suggested as a viable management tool for restoring degraded oak–pine forest communities in the southern Appalachians yet information is lacking on how this will affect ecosystem processes. Our objectives in this study were to evaluate the watershed scale effects of understory burning on total aboveground biomass, and the carbon...

  8. Responses of cavity-nesting birds to stand-replacement fire and salvage logging in ponderosa pine/Douglas-fir forests of southwestern Idaho

    Science.gov (United States)

    Victoria A. Saab; Jonathan G. Dudley

    1998-01-01

    From 1994 to 1996, researchers monitored 695 nests of nine cavity-nesting bird species and measured vegetation at nest sites and at 90 randomly located sites in burned ponderosa pine forests of southwestern Idaho. Site treatments included two types of salvage logging, and unlogged controls. All bird species selected nest sites with higher tree densities, larger...

  9. Long-term trends of changes in pine and oak foliar nitrogen metabolism in response to chronic nitrogen amendments at Harvard Forest, MA

    Science.gov (United States)

    Rakesh Minocha; Swathi A. Turlapati; Stephanie Long; William H. McDowell; Subhash C. Minocha

    2015-01-01

    We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements...

  10. Effects of site preparation subsoiling and prescribed burning on survival and growth of shortleaf pine in the Mark Twain National Forest: results after 20 growing seasons

    Science.gov (United States)

    David Gwaze; Ross Melick; Lynn McClure; Charly Studyvin; David Massengele

    2007-01-01

    The objective of this study was to evaluate the effect of subsoiling (ripping) and prescribed burning on height, survival, diameter, volume, and competition of planted shortleaf pine (Pinus echinata Mill.). The study was established at the Salem Ranger District, Mark Twain National Forest. The treatments were subsoil/burn, burn, and control with no...

  11. A Tale of Two Forests: Simulating Contrasting Lodgepole Pine and Spruce Forest Water and Carbon Fluxes Following Mortality from Bark Beetles

    Science.gov (United States)

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

    2014-12-01

    In recent decades, bark beetle infestation in western North America has reached epidemic levels. The resulting widespread forest mortality may have profound effects on present and future water and carbon cycling with potential negative consequences to a region that relies on water from montane and subalpine watersheds. We simulated stand-level ecosystem fluxes of water and carbon at two bark beetle-attacked conifer forests in southeast Wyoming, USA. The lower elevation site dominated by lodgepole pine (Pinus contorta) was attacked by mountain pine beetle (Dendroctonus ponderosae) during 2008-2010. The high elevation Engelmann spruce (Picea engelmannii) dominated site was attacked by the spruce beetle (Dendroctonus rufipennis) during roughly the same time period. Both beetle infestations resulted in >60% canopy mortality in the footprint of eddy covariance towers located at each site. However, carbon and water fluxes responses to mortality depended on the forest type. Using data collected at the sites, we scaled simulated plant hydraulic conductivity by either percent canopy mortality or loss of live tree basal area during infestation. We also simulated a case of no beetle attack. At the lodgepole site, the no-beetle model best fit the data and showed no significant change in growing season carbon flux and a 15% decrease in evapotranspiration (ET). However, at the spruce site, the simulation that tracked canopy loss agreed best with observations: carbon flux decreased by 72% and ET decreased by 31%. In the lodgepole stand, simulated soil water content agreed with spatially distributed measurements that were weighted to reflect overall mortality in the tower footprint. Although these two forest ecosystems are only 20 km apart, separated by less than 300m in elevation, and have been impacted by similar mortality agents, the associated changes in carbon and water cycling are significantly different. Beetle effects on hydrologic cycling were greatest at high elevation

  12. Long-term changes in net radiation and its components above a pine forest and a grass surface in Germany

    International Nuclear Information System (INIS)

    Kessler, A.; Jaeger, L.

    1999-01-01

    Long-term measurements (1974–1993 and 1996, respectively) of the net radiation (Q), global radiation (G), reflected global radiation (R), long-wave atmospheric radiation (A) and thermal radiation (E) of a pine forest in Southern Germany (index p) and of a grass surface in Northern Germany (index g) are compared. The influence of changes in surface properties is discussed. There are, in the case of the pine stand, forest growth and forest management and in the case of the grass surface, the shifting of the site from a climatic garden to a horizontal roof. Both series of radiant fluxes are analyzed with respect to the influences of the weather (cloudiness, heat advection). To eliminate the different influence of the solar radiation of the two sites, it is necessary to normalize by means of the global radiation G, yielding the radiation efficiency Q/G, the albedo R/G=α and the normalized long-wave net radiation (A+E)/G. Furthermore, the long-term mean values and the long-term trend of yearly mean values are discussed and, moreover, a comparison is made of individual monthly values. Q p is twice as large as Q g . The reason for this is the higher values of G and A above the pine forest and half values of α p compared to α g . E p is only a little greater than E g . The time series of the radiation fluxes show the following trends: Q p declines continuously despite a slight increase of G p . This is mainly due to the long-wave radiation fluxes. The net radiation of the grass surface Q g shows noticeably lower values after the merging of the site. This phenomenon is also dominated by the long-wave radiation processes. Although the properties of both site surfaces alter, E p and E g remain relatively stable. A p and A g show a remarkable decrease however. The reason for this is to be found in a modification of the heat advection, showing a more pronounced impact on the more continentally exposed site (pine forest). Compared to α g , α p shows only a small

  13. Ecohydrology of Lodgepole Pine Forests: Connecting Transpiration to Subsurface Flow Paths and Storage within a Subalpine Catchment

    Science.gov (United States)

    Byers, A.; Harpold, A. A.; Barnard, H. R.

    2011-12-01

    The hydrologic cycle plays a central role in regulating ecosystem structure and function. Linked studies of both subsurface and aboveground processes are needed to improve understanding of ecosystem changes that could result from climate change and disturbance in Colorado's subalpine forests. Here, we present data from plots dominated by lodgepole pine (Pinus contorta) at the Niwot Ridge LTER site on the Colorado Front Range that improves the process-level understanding of the source and fate of water between subsurface storage and plant uptake. This study utilized event-based sampling during the 2011 growing season to investigate a paradox between water sources and rooting depth in lodgepole pine. Findings from Niwot Ridge have shown that lodgepole, typically believed to be a shallow-rooted species, appear to be strongly dependent on water from snowmelt for the entire growing season. These results suggested that conifer species were accessing water from deeper in the soil than summer monsoon rain typically penetrated. In our study, the relationship between precipitation event size and depth of infiltration on a seasonal and event basis, the effective rooting depth of lodgepole pine, and hysteretic responses of transpiration to soil moisture over a growing season were examined using measurements of tree physiological processes (sap flux and water stress) and hydrological parameters (precipitation, soil moisture) as well as stable water isotope composition of xylem water, mobile and immobile soil water, snow, precipitation, and stream water. Analysis of data shows that soil moisture in deep layers (60 and 70 cm) responds to large summer rain events of 0.7 mm and greater, and that lodgepole sap flux increases by 15-30% within 24 hours of monsoon events and decreases over 72 hours or until subsequent rain. Water isotope analysis will further elucidate the source and event response of these trees. This research helps us understand whether processes known to occur in

  14. Assessment of drought related mortality in pinyon-juniper and ponderosa pine forests using Forest Inventory and Analysis data

    Science.gov (United States)

    John D. Shaw

    2008-01-01

    (Please note, this is an abstract only) Widespread mortality in several forest types is associated with several years of drought in the Southwest. Implementation of USDA Forest Service Forest Inventory and Analysis (FIA) annual inventory in several states coincided with the onset of elevated mortality rates. Analysis of data collected 2000-2004 reveals the status and...

  15. Variability of sun-induced chlorophyll fluorescence according to stand age-related processes in a managed loblolly pine forest.

    Science.gov (United States)

    Colombo, Roberto; Celesti, Marco; Bianchi, Remo; Campbell, Petya K E; Cogliati, Sergio; Cook, Bruce D; Corp, Lawrence A; Damm, Alexander; Domec, Jean-Christophe; Guanter, Luis; Julitta, Tommaso; Middleton, Elizabeth M; Noormets, Asko; Panigada, Cinzia; Pinto, Francisco; Rascher, Uwe; Rossini, Micol; Schickling, Anke

    2018-02-20

    Leaf fluorescence can be used to track plant development and stress, and is considered the most direct measurement of photosynthetic activity available from remote sensing techniques. Red and far-red sun-induced chlorophyll fluorescence (SIF) maps were generated from high spatial resolution images collected with the HyPlant airborne spectrometer over even-aged loblolly pine plantations in North Carolina (United States). Canopy fluorescence yield (i.e., the fluorescence flux normalized by the light absorbed) in the red and far-red peaks was computed. This quantifies the fluorescence emission efficiencies that are more directly linked to canopy function compared to SIF radiances. Fluorescence fluxes and yields were investigated in relation to tree age to infer new insights on the potential of those measurements in better describing ecosystem processes. The results showed that red fluorescence yield varies with stand age. Young stands exhibited a nearly twofold higher red fluorescence yield than mature forest plantations, while the far-red fluorescence yield remained constant. We interpreted this finding in a context of photosynthetic stomatal limitation in aging loblolly pine stands. Current and future satellite missions provide global datasets of SIF at coarse spatial resolution, resulting in intrapixel mixture effects, which could be a confounding factor for fluorescence signal interpretation. To mitigate this effect, we propose a surrogate of the fluorescence yield, namely the Canopy Cover Fluorescence Index (CCFI) that accounts for the spatial variability in canopy structure by exploiting the vegetation fractional cover. It was found that spatial aggregation tended to mask the effective relationships, while the CCFI was still able to maintain this link. This study is a first attempt in interpreting the fluorescence variability in aging forest stands and it may open new perspectives in understanding long-term forest dynamics in response to future climatic

  16. Longleaf Pine Ground-Layer Vegetation in Francis Marion National Forest: Reintroduction, Restoration, and Vegetation Assembly

    International Nuclear Information System (INIS)

    Glitzenstein, J.; Streng, D.; Wade, D.

    2001-01-01

    Study represents significant progress in understanding of compositional gradients in longleaf pine plant communities of Central South Carolina. Study shows the importance of water table depths as a controlling variable with vegetation patterns in the field and similar effects in a garden experiment. Grass planting study suggests that observed field distributions of dormant pine savannah grasses derive from complex interactive effects of fire history, hydrology and light environments. Use of regional longleaf data set to identify candidate species for introduction also appears to be a pioneering effort

  17. Longleaf Pine Ground-Layer Vegetation in Francis Marion National Forest: Reintroduction, Restoration, and Vegetation Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Glitzenstein, J.; Streng, D.; Wade, D.

    2001-01-01

    Study represents significant progress in understanding of compositional gradients in longleaf pine plant communities of Central South Carolina. Study shows the importance of water table depths as a controlling variable with vegetation patterns in the field and similar effects in a garden experiment. Grass planting study suggests that observed field distributions of dormant pine savannah grasses derive from complex interactive effects of fire history, hydrology and light environments. Use of regional longleaf data set to identify candidate species for introduction also appears to be a pioneering effort.

  18. Response of water use efficiency to summer drought in a boreal Scots pine forest in Finland

    Directory of Open Access Journals (Sweden)

    Y. Gao

    2017-09-01

    Full Text Available The influence of drought on plant functioning has received considerable attention in recent years, however our understanding of the response of carbon and water coupling to drought in terrestrial ecosystems still needs to be improved. A severe soil moisture drought occurred in southern Finland in the late summer of 2006. In this study, we investigated the response of water use efficiency to summer drought in a boreal Scots pine forest (Pinus sylvestris on the daily time scale mainly using eddy covariance flux data from the Hyytiälä (southern Finland flux site. In addition, simulation results from the JSBACH land surface model were evaluated against the observed results. Based on observed data, the ecosystem level water use efficiency (EWUE; the ratio of gross primary production, GPP, to evapotranspiration, ET showed a decrease during the severe soil moisture drought, while the inherent water use efficiency (IWUE; a quantity defined as EWUE multiplied with mean daytime vapour pressure deficit, VPD increased and the underlying water use efficiency (uWUE, a metric based on IWUE and a simple stomatal model, is the ratio of GPP multiplied with a square root of VPD to ET was unchanged during the drought. The decrease in EWUE was due to the stronger decline in GPP than in ET. The increase in IWUE was because of the decreased stomatal conductance under increased VPD. The unchanged uWUE indicates that the trade-off between carbon assimilation and transpiration of the boreal Scots pine forest was not disturbed by this drought event at the site. The JSBACH simulation showed declines of both GPP and ET under the severe soil moisture drought, but to a smaller extent compared to the observed GPP and ET. Simulated GPP and ET led to a smaller decrease in EWUE but a larger increase in IWUE because of the severe soil moisture drought in comparison to observations. As in the observations, the simulated uWUE showed no changes in the drought event. The

  19. Soil respiration shifts as drought-induced tree substitution advances from Scots pine to Holm oak forest

    Science.gov (United States)

    Barba, Josep; Curiel Yuste, Jorge; Poyatos, Rafael; Janssens, Ivan A.; Lloret, Francisco

    2014-05-01

    There is more and more evidences that the current global warming trend and the increase of frequency and intensity of drought events during the last decades in the Northern hemisphere are currently producing an increment of drought-induced forest die-off events, being the Mediterranean region one of the most affected areas. This drought-induced mortality could lead in a vegetation shift with unpredicted consequences in carbon pools, where soils are the most determinant factor in this carbon balance as they contain over two-thirds of carbon on forest ecosystems. There are several uncertainties related on the interaction between soil, environmental conditions and vegetation shifts that could modify their capability to be net carbon sinks or sources in a warming context. We studied soil respiration and its heterotrophic (RH) and autotrophic (Ra) (split in fine roots [Rr] and mycorrhizal respiration [Rs]) components in a mixed Mediterranean forest where Scots pine (Pinus sylvestris L.) are suffering from drought-induced die-off and replaced by Holm oak (Quercus ilex L.) as the dominant tree species. Soil respiration fluxes and its fractions were measured every two weeks during one year at four stages of the substitution process (non defoliated pines [NDP], defoliated pines [DFP], dead pines [DP] and Holm oak [HO]), using the mesh exclusion method. The aims were (i) to describe soil respiration fluxes in a drought-induced secondary successional process, (ii) to test whether the changes in vegetation affected soil respiration fluxes and (iii) to determine the influence of environmental and abiotic variables on the different soil respiration fractions. Total soil respiration was 10.10±6.17 TC ha-1 y-1, RH represented the 67% of the total, Ra represented the 34% of the total, and Rr and Rs were the 22 and 12%, respectively. Significant differences were found in total soil respiration and RH between NDP and HO, being lower in HO than in NDP (34% in total and 48% in RH). No

  20. Borax Stump Treatment for Control of Annosus Root Disease in the Eastside Pine Type Forests of Northeastern California

    Science.gov (United States)

    John T. Kliejunas

    1989-01-01

    A historical perspective and description of recent studies on the use of borax to treat pine stumps against infection by Heterobasidion annosum in eastside pine stands of northeastern California are presented. The studies indicate that boraxing of pines in eastside pine stands is an effective means of preventing annosus infection. Data and...

  1. A 20-year reassessment of the health and status of whitebark pine forests in the Bob Marshall Wilderness Complex, Montana

    Science.gov (United States)

    Molly L. Retzlaff; Signe B. Leirfallom; Robert E. Keane

    2016-01-01

    Whitebark pine plays a prominent role in high elevation ecosystems of the northern Rocky Mountains. It is an important food source for many birds and mammals as well as an essential component of watershed stabilization. Whitebark pine is vanishing from the landscape due to three main factors: white pine blister rust, mountain pine beetle outbreaks, and successional...

  2. First look at smoke emissions from prescribed burns in long-unburned longleaf pine forests

    Science.gov (United States)

    Sheryl K. Akagi; Robert J. Yokelson; Ian R. Burling; David R. Weise; James Reardon; Shawn Urbanski; Timothy J. Johnson

    2014-01-01

    While fire has long played a role in the longleaf pine ecosystem, there are still some stands in the southeastern United States where fire has not been reintroduced and fuels have accumulated for 50 years or more. As part of a larger study examining fuel loading and smoke emissions on Department of Defense installations in the southeastern U.S., fuels and trace...

  3. Compartmental Model For Uptake Of 137cs By Pine In Forest Soil ...

    African Journals Online (AJOL)

    A compartmental model of soil to pine tree transfer of 137Cs following the Chernobyl nuclear accident is presented. The model was validated using data collected in 1996 at five sites in Northern Ukraine. The transfer constants of 137Cs between model compartments are estimated using a semi-empirical method.

  4. Nitrogen availability alters macrofungal basidiomycete Blackwell Publishing, Ltd. community structure in optimally fertilized loblolly pine forests

    Science.gov (United States)

    Ivan P. Edwards; Jennifer L. Cripliver; Andrew R. Gillespie; Kurt H. Johnsen; M. Scholler; Ronald F. Turco

    2004-01-01

    We investigated the effect of an optimal nutrition strategy designed to maximize loblolly pine (Pinus taeda) growth on the rank abundance structure and diversity of associated basidiomycete communities.We conducted both small- and large-scale below-ground surveys 10 years after the initiation of optimal...

  5. Remote estimation of a managed pine forest evapotranspiration with geospatial technology

    Science.gov (United States)

    S. Panda; D.M. Amatya; G Sun; A. Bowman

    2016-01-01

    Remote sensing has increasingly been used to estimate evapotranspiration (ET) and its supporting parameters in a rapid, accurate, and cost-effective manner. The goal of this study was to develop remote sensing-based models for estimating ET and the biophysical parameters canopy conductance (gc), upper-canopy temperature, and soil moisture for a mature loblolly pine...

  6. Litter Decomposition and Soil Respiration Responses to Fuel-Reduction Treatments in Piedmond Loblolly Pine Forests

    Science.gov (United States)

    Mac A. Callaham; Peter H. Anderson; Thomas A. Waldrop; Darren J. Lione; Victor B. Shelburne

    2004-01-01

    As part of the National Fire and Fire Surrogate Study, we measured the short-term effects of different fuel-management practices on leaf litter decomposition and soil respiration in loblolly pine stands on the upper Piedmont of South Carolina. These stands had been subjected to a factorial arrangement of experimental fuel-management treatments that included prescribed...

  7. Soil organic matter fractions in loblolly pine forests of Coastal North Carolina managed for bioenergy production

    Science.gov (United States)

    Kevan J. Minick; Brian D. Strahm; Thomas R. Fox; Eric B. Surce; Zakiya H. Leggett

    2015-01-01

    Dependence on foreign oil continues to increase, and concern over rising atmospheric CO2 and other greenhouse gases has intensified research into sustainable biofuel production. Intercropping switchgrass (Panicum virgatum L.) between planted rows of loblolly pine (Pinus taeda L.) offers an opportunity to utilize inter-row space that typically contains herbaceous and...

  8. Soil Respiration Changes after Prescribed Fires in Spanish Black Pine (Pinus nigra Arn. ssp. salzmannii Monospecific and Mixed Forest Stands

    Directory of Open Access Journals (Sweden)

    Pedro Antonio Plaza-Álvarez

    2017-07-01

    Full Text Available Soil respiration is a major carbon pathway sensitive to environmental changes. Using prescribed burnings to reduce fuel accumulation and lower risks of large-scale wildfires has recently become more important. Prescribed burning can significantly alter the soil environment, but its effect in practice on soil respiration is not sufficiently understood. We evaluated the effects of prescribed burning on soil respiration before and after burning (May–July 2016. Prescribed burning was conducted in two natural pine areas by comparing a mixed stand of Pinus nigra Arn. ssp. salzmannii with Pinus pinaster Ait. to a pure stand of Pinus nigra Arn. ssp. salzmannii in the central Iberian Peninsula. Soil respiration was measured by an EGM-4 (Environmental Gas Monitor infrared gas analyser in both burned and unburned (control plots. Burnings were low-intensity, and slightly more energetic in the pure stand given its larger litter volume. Post-burning soil respiration followed a similar evolution to that in the control plots, but was greater in the pure stand burned zone and slightly lower in the burned plots in the mixed stand. No significant differences were found in any stand. Soil respiration significantly changed in temporal evolution due to increasing temperatures when summer began. We conclude that prescribed fire induces no changes in SR immediately after fire. This study helps understand how prescribed burnings can affect soil respiration in pure and mixed Spanish black pine forest stands.

  9. Effects of Small-Scale Dead Wood Additions on Beetles in Southeastern U.S. Pine Forests

    Directory of Open Access Journals (Sweden)

    Chris E. Carlton

    2012-08-01

    Full Text Available Pitfall traps were used to sample beetles (Coleoptera in plots with or without inputs of dead loblolly pine (Pinus taeda L. wood at four locations (Louisiana, Mississippi, North Carolina and Texas on the coastal plain of the southeastern United States. The plots were established in 1998 and sampling took place in 1998, 1999, and 2002 (only 1998 for North Carolina. Overall, beetles were more species rich, abundant and diverse in dead wood addition plots than in reference plots. While these differences were greatest in 1998 and lessened thereafter, they were not found to be significant in 1998 due largely to interactions between location and treatment. Specifically, the results from North Carolina were inconsistent with those from the other three locations. When these data were excluded from the analyses, the differences in overall beetle richness for 1998 became statistically significant. Beetle diversity was significantly higher in the dead wood plots in 1999 but by 2002 there were no differences between dead wood added and control plots. The positive influence of dead wood additions on the beetle community can be largely attributed to the saproxylic fauna (species dependent on dead wood, which, when analyzed separately, were significantly more species rich and diverse in dead wood plots in 1998 and 1999. Ground beetles (Carabidae and other species, by contrast, were not significantly affected. These results suggest manipulations of dead wood in pine forests have variable effects on beetles according to life history characteristics.

  10. Simulated impacts of mountain pine beetle and wildfire disturbances on forest vegetation composition and carbon stocks in the Southern Rocky Mountains

    Science.gov (United States)

    Caldwell, Megan K.; Hawbaker, Todd J.; Briggs, Jenny S.; Cigan, P.W.; Stitt, Susan

    2013-01-01

    Forests play an important role in sequestering carbon and offsetting anthropogenic greenhouse gas emissions, but changing disturbance regimes may compromise the capability of forests to store carbon. In the Southern Rocky Mountains, a recent outbreak of mountain pine beetle (Dendroctonus ponderosae; MPB) has caused levels of tree mortality that are unprecedented in recorded history. To evaluate the long-term impacts of both this insect outbreak and another characteristic disturbance in these forests, high-severity wildfire, we simulated potential changes in species composition and carbon stocks using the Forest Vegetation Simulator (FVS). Simulations were completed for 3 scenarios (no disturbance, actual MPB infestation, and modeled wildfire) using field data collected in 2010 at 97 plots in the lodgepole pine-dominated forests of eastern Grand County, Colorado, which were heavily impacted by MPB after 2002. Results of the simulations showed that (1) lodgepole pine remained dominant over time in all scenarios, with basal area recovering to pre-disturbance levels 70–80 yr after disturbance; (2) wildfire caused a greater magnitude of change than did MPB in both patterns of succession and distribution of carbon among biomass pools; (3) levels of standing-live carbon returned to pre-disturbance conditions after 40 vs. 50 yr following MPB vs. wildfire disturbance, respectively, but took 120 vs. 150 yr to converge with conditions in the undisturbed scenario. Lodgepole pine forests appear to be relatively resilient to both of the disturbances we modeled, although changes in climate, future disturbance regimes, and other factors may significantly affect future rates of regeneration and ecosystem response.

  11. [Effects of selective cutting on soil phosphorus forms and availability in Korean pine broad-leaved forest in Xiaoxing'an Mountains of China.

    Science.gov (United States)

    Zhang, Xin; Gu, Hui Yan; Chen, Xiang Wei

    2018-02-01

    In order to clarify the effects of selective cutting on soil phosphorus availability in Korean pine broad-leaved forest, surface soil (0-10 cm) samples from original Korean pine broad-leaved forest and natural forests with mild, medium and intensive cutting disturbances were collected. The Sui modified Hedley phosphorus fractionation method was used to continuously extract soil samples and analyzed the differences and changes of soil phosphorus fractions from different experimental stands. The results showed that the soil total phosphorus content of Korean pine broad-leaved forest varied from 1.09 to 1.66 g·kg -1 , with the original stand and intensive cutting disturbance stand being the maximum and minimum one, respectively. The differences of soil total phosphorus content among cutting disturbance levels were significant. The Olsen phosphorus and phosphorus activation coefficients changed with an amplitude of 7.26-17.79 mg·kg -1 and 0.67%-1.07%, respectively. Both of them significantly decreased with the increase of selective cutting disturbance level. The concentrations of all P fractions except HCl-P o , i.e., H 2 O-P i , NaHCO 3 -P, NaOH-P, HCl-P i , Residual-P, decreased with increasing cutting disturbance levels compared with original forest. The correlation coefficient between H 2 O-P i and soil Olsen phosphorus was the highest (0.98), though it only accounted for 1.5%-2.2% of the total phosphorus. NaOH-P content contributed to more than 48.0% of the total phosphorus, acknowledged as the potential source of soil phosphorus. In conclusion, selective cutting disturbance could constrain phosphorus storage and soil phosphorus availabi-lity of the Korean pine broad-leaved forests by significantly reducing the content of soil inorganic phosphorus and NaOH-P o , and such trends were positively dependent on the intensity of selective cutting.

  12. Comparison of snag densities among regeneration treatments in mixed pine-hardwood forests

    Science.gov (United States)

    Roger W. Perry; Ronald E. Thill

    2013-01-01

    Standing dead trees (snags) are an important component of forest ecosystems, providing foraging, nesting, and roosting substrate for a variety of vertebrates. We examined the effects of four forest regeneration treatments on residual snag density and compared those with densities found in unharvested, naturally regenerated forests (controls) during the second, fourth,...

  13. Modern fire regime resembles historical fire regime in a ponderosa pine forest on Native American land

    Science.gov (United States)

    Amanda B. Stan; Peter Z. Fule; Kathryn B. Ireland; Jamie S. Sanderlin

    2014-01-01

    Forests on tribal lands in the western United States have seen the return of low-intensity surface fires for several decades longer than forests on non-tribal lands. We examined the surface fire regime in a ponderosa pinedominated (Pinus ponderosa) forest on the Hualapai tribal lands in the south-western United States. Using fire-scarred trees, we inferred temporal (...

  14. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America.

    Directory of Open Access Journals (Sweden)

    Jens T Stevens

    Full Text Available Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA program reflects the timing of historical high-severity (i.e. stand-replacing fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1 the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2 recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.

  15. Average Stand Age from Forest Inventory Plots Does Not Describe Historical Fire Regimes in Ponderosa Pine and Mixed-Conifer Forests of Western North America.

    Science.gov (United States)

    Stevens, Jens T; Safford, Hugh D; North, Malcolm P; Fried, Jeremy S; Gray, Andrew N; Brown, Peter M; Dolanc, Christopher R; Dobrowski, Solomon Z; Falk, Donald A; Farris, Calvin A; Franklin, Jerry F; Fulé, Peter Z; Hagmann, R Keala; Knapp, Eric E; Miller, Jay D; Smith, Douglas F; Swetnam, Thomas W; Taylor, Alan H

    Quantifying historical fire regimes provides important information for managing contemporary forests. Historical fire frequency and severity can be estimated using several methods; each method has strengths and weaknesses and presents challenges for interpretation and verification. Recent efforts to quantify the timing of historical high-severity fire events in forests of western North America have assumed that the "stand age" variable from the US Forest Service Forest Inventory and Analysis (FIA) program reflects the timing of historical high-severity (i.e. stand-replacing) fire in ponderosa pine and mixed-conifer forests. To test this assumption, we re-analyze the dataset used in a previous analysis, and compare information from fire history records with information from co-located FIA plots. We demonstrate that 1) the FIA stand age variable does not reflect the large range of individual tree ages in the FIA plots: older trees comprised more than 10% of pre-stand age basal area in 58% of plots analyzed and more than 30% of pre-stand age basal area in 32% of plots, and 2) recruitment events are not necessarily related to high-severity fire occurrence. Because the FIA stand age variable is estimated from a sample of tree ages within the tree size class containing a plurality of canopy trees in the plot, it does not necessarily include the oldest trees, especially in uneven-aged stands. Thus, the FIA stand age variable does not indicate whether the trees in the predominant size class established in response to severe fire, or established during the absence of fire. FIA stand age was not designed to measure the time since a stand-replacing disturbance. Quantification of historical "mixed-severity" fire regimes must be explicit about the spatial scale of high-severity fire effects, which is not possible using FIA stand age data.

  16. Landscape variation in tree regeneration and snag fall drive fuel loads in 24-year old post-fire lodgepole pine forests.

    Science.gov (United States)

    Nelson, Kellen N; Turner, Monica G; Romme, William H; Tinker, Daniel B

    2016-12-01

    Escalating wildfire in subalpine forests with stand-replacing fire regimes is increasing the extent of early-seral forests throughout the western USA. Post-fire succession generates the fuel for future fires, but little is known about fuel loads and their variability in young post-fire stands. We sampled fuel profiles in 24-year-old post-fire lodgepole pine (Pinus contorta var. latifolia) stands (n = 82) that regenerated from the 1988 Yellowstone Fires to answer three questions. (1) How do canopy and surface fuel loads vary within and among young lodgepole pine stands? (2) How do canopy and surface fuels vary with pre- and post-fire lodgepole pine stand structure and environmental conditions? (3) How have surface fuels changed between eight and 24 years post-fire? Fuel complexes varied tremendously across the landscape despite having regenerated from the same fires. Available canopy fuel loads and canopy bulk density averaged 8.5 Mg/ha (range 0.0-46.6) and 0.24 kg/m 3 (range: 0.0-2.3), respectively, meeting or exceeding levels in mature lodgepole pine forests. Total surface-fuel loads averaged 123 Mg/ha (range: 43-207), and 88% was in the 1,000-h fuel class. Litter, 1-h, and 10-h surface fuel loads were lower than reported for mature lodgepole pine forests, and 1,000-h fuel loads were similar or greater. Among-plot variation was greater in canopy fuels than surface fuels, and within-plot variation was greater than among-plot variation for nearly all fuels. Post-fire lodgepole pine density was the strongest positive predictor of canopy and fine surface fuel loads. Pre-fire successional stage was the best predictor of 100-h and 1,000-h fuel loads in the post-fire stands and strongly influenced the size and proportion of sound logs (greater when late successional stands had burned) and rotten logs (greater when early successional stands had burned). Our data suggest that 76% of the young post-fire lodgepole pine forests have 1,000-h fuel loads that exceed levels

  17. Roost selection by big brown bats in forests of Arkansas: importance of pine snags and open forest habitats to males

    Science.gov (United States)

    Roger W. Perry; Ronald E. Thill

    2008-01-01

    Although Eptesicus fuscus (Big Brown Bat) has been widely studied, information on tree-roosting in forests by males is rare, and little information is available on tree roosting in the southeastern United States. Our objectives were to characterize diurnal summer roosts, primarily for male Big Brown Bats, and to determine relationships between forest...

  18. Enhanced tools for predicting annual stone pine (Pinus pinea L.) cone production at tree and forest scale in Inner Spain

    Energy Technology Data Exchange (ETDEWEB)

    Calama, R.; Gordo, J.; Madrigal, G.; Mutke, S.; Conde, M.; Montero, G.; Pardos, M.

    2016-07-01

    Aim of the study: To present a new spatiotemporal model for Pinus pinea L. annual cone production with validity for Spanish Northen Plateau and Central Range regions. The new model aims to deal with detected deficiencies in previous models: temporal shortage, overestimation of cone production on recent years, incompatibility with data from National Forest Inventory, difficulty for upscaling and ignorance of the inhibitory process due to resource depletion. Area of study: Spanish Northern Plateau and Central Range regions, covering an area where stone pine occupies more than 90,000 ha. Material and methods: Fitting data set include 190 plots and more than 1000 trees were cone production has been annually collected from 1996 to 2014. Models were fitted independently for each region, by means of zero-inflated log normal techniques. Validation of the models was carried out over the annual series of cone production at forest scale. Results: The spatial and temporal factors influencing cone production are similar in both regions, thus the main regional differences in cone yield are related with differences in the phenological timing, the intensity of the influent factors and forest intrinsic conditions. A significant inhibition of floral induction by resource depletion was detected and included into the model. Upscaling the model results in accurate prediction at forest scale. Research highlights: [1] The new model for annual cone production surpass the detected deficiencies of previous models, accurately predicting recent decay in cone production; [2] Regional differences in cone production are due to phenological and seasonal climatic differences rather than to between provenances genetic differences. (Author)

  19. Whitebark pine planting guidelines

    Science.gov (United States)

    Ward McCaughey; Glenda L. Scott; Kay L. Izlar

    2009-01-01

    This article incorporates new information into previous whitebark pine guidelines for planting prescriptions. Earlier 2006 guidelines were developed based on review of general literature, research studies, field observations, and standard US Forest Service survival surveys of high-elevation whitebark pine plantations. A recent study of biotic and abiotic factors...

  20. Direct seeding southern pines: history and status of a technique developed for restoring cutover forests

    Science.gov (United States)

    J.P. Barnett

    2014-01-01

    Early in the 20th century the deforestation resulting from the “golden-age of lumbering” left millions of acres of forest land in the need for reforestation. The challenge was so extreme that foresters of the early 1930s estimated that it would take 900 to 1,000 years at the then rate of planting to reforest the denuded forest land that occurred throughout the Nation....

  1. Enhancing Stand Structure through Snag Creation in Northeastern U.S. Forests: Using Ethanol Injections and Bark Beetle Pheromones to Artificially Stress Red Maple and White Pine

    Directory of Open Access Journals (Sweden)

    Kevin J. Dodds

    2016-06-01

    Full Text Available We investigated two methods to create white pine and red maple snags in a forested setting. The first involved injecting trees with ethanol at two times (single Ethanol (ETOH and double ETOH injections to increase attractiveness to insects and elicit attacks on trees. The second method was unique to white pines and involved both injection treatments in combination with baiting trees with Ips-specific pheromones. Three of five white pines from the double ETOH treatment died in the second year. Species including Ips pini (Say, Ips grandicollis Eichhoff, Orthotomicus caelatus Eichhoff, Crypturgus borealis Swaine and Monochamus notatus (Drury responded more strongly to at least one of the treatments over control trees. However, there were no differences found in individual Scolytinae or Cerambycidae species response to treatments in red maple. Fitness (FV/FM and vitality (PIabs were both significantly reduced in both ETOH treatments compared to controls in white pine. In red maple, fitness was reduced in the double ETOH treated trees but the final mean FV/FM values were within the approximate optimal of health. Ethanol injections, in combination with Ips-specific semiochemicals, show promise for creating standing coarse woody debris (CWD in white pine. Injecting ethanol was not effective for stressing red maple.

  2. Age-related patterns of forest complexity and carbon storage in pine and aspen-birch ecosystems of northern Minnesota, USA

    International Nuclear Information System (INIS)

    Bradford, J.B.; Kastendick, D.N.

    2010-01-01

    Forest managers are now developing strategies to mitigate increases in atmospheric carbon dioxide (CO 2 ) and help stands to adapt to new climatic conditions. This study characterized the influence of stand age on carbon storage and sequestration in chronosequences of even-aged red pine and aspen-birch stands in northern Minnesota. The aim of the study was to determine the impact of age-related management strategies on carbon storage and forest complexity. The pine chronosequences ranged from 7 to 160 years. Aspen chronosequences ranged from 6 to 133 years. Field measurements of the trees were compiled into 5 carbon pools. Carbon storage variables were averaged within each stand in order to conduct a regression analysis. The study showed that forest complexity was positively related to stand age in all of the measured response variables except species richness. Relationships between compositional complexity and stand age depended on forest type. Total carbon storage also increased with age. Results of the study showed that age plays an important role in overall ecosystem carbon storage. The study can be used to provide insights into the overall costs and benefits of forest management strategies that favour younger or older forests. 45 refs., 2 figs.

  3. Growing season soil moisture following restoration treatments of varying intensity in semi-arid ponderosa pine forests

    Science.gov (United States)

    O'Donnell, F. C.; Springer, A. E.; Sankey, T.; Masek Lopez, S.

    2014-12-01

    Forest restoration projects are being planned for large areas of overgrown semi-arid ponderosa pine forests of the Southwestern US. Restoration involves the thinning of smaller trees and prescribed or managed fire to reduce tree density, restore a more natural fire regime, and decrease the risk of catastrophic wildfire. The stated goals of these projects generally reduced plant water stress and improvements in hydrologic function. However, little is known about how to design restoration treatments to best meet these goals. As part of a larger project on snow cover, soil moisture, and groundwater recharge, we measured soil moisture, an indicator of plant water status, in four pairs of control and restored sites near Flagstaff, Arizona. The restoration strategies used at the sites range in both amount of open space created and degree of clustering of the remaining trees. We measured soil moisture using 30 cm vertical time domain reflectometry probes installed on 100 m transects at 5 m intervals so it would be possible to analyze the spatial pattern of soil moisture. Soil moisture was higher and more spatially variable in the restored sites than the control sites with differences in spatial pattern among the restoration types. Soil moisture monitoring will continue until the first snow fall, at which point measurements of snow depth and snow water equivalent will be made at the same locations.

  4. Tree rings provide early warning signals of jack pine mortality across a moisture gradient in the southern boreal forest

    Science.gov (United States)

    Mamet, S. D.; Chun, K. P.; Metsaranta, J. M.; Barr, A. G.; Johnstone, J. F.

    2015-08-01

    Recent declines in productivity and tree survival have been widely observed in boreal forests. We used early warning signals (EWS) in tree ring data to anticipate premature mortality in jack pine (Pinus banksiana)—an extensive and dominant species occurring across the moisture-limited southern boreal forest in North America. We sampled tree rings from 113 living and 84 dead trees in three soil moisture regimes (subxeric, submesic, subhygric) in central Saskatchewan, Canada. We reconstructed annual increments of tree basal area to investigate (1) whether we could detect EWS related to mortality of individual trees, and (2) how water availability and tree growth history may explain the mortality warning signs. EWS were evident as punctuated changes in growth patterns prior to transition to an alternative state of reduced growth before dying. This transition was likely triggered by a combination of severe drought and insect outbreak. Higher moisture availability associated with a soil moisture gradient did not appear to reduce tree sensitivity to stress-induced mortality. Our results suggest tree rings offer considerable potential for detecting critical transitions in tree growth, which are linked to premature mortality.

  5. Effects of seeding ryegrass (Lolium multiflorum) on vegetation recovery following fire in a ponderosa pine (Pinus ponderosa) forest

    Science.gov (United States)

    Barclay, Angela D.; Betancourt, Julio L.; Allen, Craig D.

    2004-01-01

    Forty-nine vegetation transects were measured in 1997 and 1998 to determine the impact of grass seeding after the 1996 Dome Fire, which burned almost 6900 ha of ponderosa pine (Pinus ponderosa Lawson) forest in the Jemez Mountains of north-central New Mexico. High- and moderate-burned areas in Santa Fe National Forest were seeded with a mixture that included the exotic ryegrass (Lolium multiflorum Lam.). Adjacent burned areas of Bandelier National Monument were not seeded, and were used as a control in the post-seeding study. On the seeded plots, foliar cover of ryegrass declined from 1997 to 1998 due to self-inhibition and/or reduced precipitation from 1997 to 1998. Foliar cover and diversity of native forbs were greater in 1997 than 1998, probably due to a wet growing season in 1997. Cover, species richness, and diversity of native forbs were highest in non-seeded areas of moderate- and high-burn intensities. Regeneration and survivorship of conifer seedlings decreased as ryegrass cover increased, particularly in areas of high-burn intensity. Exotic plant cover, mostly horseweed [Conyza canadensis (L.) Cronq.], increased from 1997 to 1998 in non-seeded areas of moderate- and high-burn intensity. Both the initial success of seeding and the eventual impacts on native vegetation were strongly modulated by climate variability.

  6. Short-Term Belowground Responses to Thinning and Burning Treatments in Southwestern Ponderosa Pine Forests of the USA

    Directory of Open Access Journals (Sweden)

    Steven T. Overby

    2016-02-01

    Full Text Available Microbial-mediated decomposition and nutrient mineralization are major drivers of forest productivity. As landscape-scale fuel reduction treatments are being implemented throughout the fire-prone western United States of America, it is important to evaluate operationally how these wildfire mitigation treatments alter belowground processes. We quantified these important belowground components before and after management-applied fuel treatments of thinning alone, thinning combined with prescribed fire, and prescribed fire in ponderosa pine (Pinus ponderosa stands at the Southwest Plateau, Fire and Fire Surrogate site, Arizona. Fuel treatments did not alter pH, total carbon and nitrogen (N concentrations, or base cations of the forest floor (O horizon or mineral soil (0–5 cm during this 2-year study. In situ rates of net N mineralization and nitrification in the surface mineral soil (0–15 cm increased 6 months after thinning with prescribed fire treatments; thinning only resulted in net N immobilization. The rates returned to pre-treatment levels after one year. Based on phospholipid fatty acid composition, microbial communities in treated areas were similar to untreated areas (control in the surface organic horizon and mineral soil (0–5 cm after treatments. Soil potential enzyme activities were not significantly altered by any of the three fuel treatments. Our results suggest that a variety of one-time alternative fuel treatments can reduce fire hazard without degrading soil fertility.

  7. Trace gas emissions from a chronosequence of bark beetle-infested lodgepole pine (Pinus contorta) forest stands

    Science.gov (United States)

    Norton, U.; Pendall, E.; Ewers, B. E.; Borkhuu, B.

    2011-12-01

    Severe outbreak of mountain pine beetle (MPB) and associated blue stain fungi have killed millions of hectares of coniferous forests in Western North America. This unprecedented disturbance has critically impacted ecosystem biogeochemistry and net carbon (C) and nitrogen (N) fluxes. However, the effects on greenhouse gas (GHG) emissions and drivers of biogeochemical processes that trigger GHG emissions following MPB infestations are not well understood. Such information can help assess regional-level changes in ecosystem C and N budgets and large-scale disturbance impacts on gas exchange between the atmosphere and terrestrial ecosystem. The overall objective of this research was to assess the immediate responses of GHG fluxes and soil C and N mineralization rates along a chronosequence of recently infested (1-yr, 3-yr and 4-yr ago) and uninfested (150-yr, 20-yr and 15-yr old) lodgepole pine stands in Medicine Bow National Forest in southeastern Wyoming. We hypothesize that MPB-induced tree mortality significantly changes stand-level hydrology, soil organic matter quality and chemistry of aboveground and belowground plant inputs. Consequently, these modifications influence nitrous oxide (N2O) emissions and methane (CH4) assimilation. Biweekly GHG measurements using static chambers were carried out during three consecutive snow-free growing seasons. Our results suggest that a stand infested within a year already shows a 20% increase in spring N2O production and a small decline in summer CH4 assimilation when compared to uninfested stands. Stands infested three and four years prior to our measurements produce over three times more N2O and assimilate three to five times less CH4 when compared to uninfested stands. In addition, a notable increase in soil moisture content and soil mineral N concentrations following early onset of the MPB infestation was also observed. An overall increase in N2O production and decline in CH4 assimilation following MPB infestation may

  8. Modeling forest harvesting effects on landscape pattern in the Northwest Wisconsin Pine Barrens

    Science.gov (United States)

    Volker C. Radeloff; David J. Mladenoff; Eric J. Gustafson; Robert M. Scheller; Patrick A. Zollner; Hong S. Heilman; H. Resit Akcakaya

    2006-01-01

    Forest management shapes landscape patterns, and these patterns often differ significantly from those typical for natural disturbance regimes. This may affect wildlife habitat and other aspects of ecosystem function. Our objective was to examine the effects of different forest management decisions on landscape pattern in a fire adapted ecosystem. We used a factorial...

  9. Spatially random mortality in old-growth red pine forests of northern Minnesota

    Science.gov (United States)

    Tuomas ​Aakala; Shawn Fraver; Brian J. Palik; Anthony W. D' Amato

    2012-01-01

    Characterizing the spatial distribution of tree mortality is critical to understanding forest dynamics, but empirical studies on these patterns under old-growth conditions are rare. This rarity is due in part to low mortality rates in old-growth forests, the study of which necessitates long observation periods, and the confounding influence of tree in-growth during...

  10. Effects of repeated growing season prescribed fire on the structure and composition of pine-hardwood forests in the southeastern Piedmont, USA

    Science.gov (United States)

    Matthew Reilly; Kenneth Outcalt; Joseph O’Brien; Dale Wade

    2016-01-01

    We examined the effects of repeated growing season prescribed fire on the structure and composition of mixed pine–hardwood forests in the southeastern Piedmont region, Georgia, USA. Plots were burned two to four times over an eight-year period with low intensity surface fires during one of four six-week long periods from early April to mid-September. Density...

  11. Impact of the Mountain Pine Beetle on the Forest Carbon Cycle in British Columbia from 1999 TO 2008 (Invited)

    Science.gov (United States)

    Chen, J. M.; Czurylowicz, P.; Mo, G.; Black, T. A.

    2013-12-01

    The unprecedented mountain pine beetle (Dendroctonus ponderosae) (MPB) outbreak in British Columbia starting in 1998 affected about 50% of the lodgepole pine (Pinus contorta var. latifolia) forests occupying about 50% of the land area of the province. The impact of this outbreak on the C cycle is assessed in this study. Annual leaf area index (LAI) maps of the affected area from 1999 to 2008 were produced using SPOT VEGETATION data, and net ecosystem production (NEP) was modeled using inputs of LAI, land cover, soil texture and daily meteorological data with the Boreal Ecosystem Productivity Simulator (BEPS). Both LAI and NEP were validated using field measurements. LAI was found to decrease on average by 20% compared to pre-outbreak conditions, while NEP decreased on average by 90%. Annual NEP values ranged from 2.4 to -8.0 Tg C between 1999 and 2008, with the ecosystem changing from a carbon sink to a carbon source in 2000. The annual average NEP was -2.9 Tg C over the 10 years, resulting in a total loss of carbon of 29 Tg C to the atmosphere. The inter-annual variability of both LAI and NEP was characterized by substantial initial decreases followed by steady increases from 2006 to 2008 with NEP returning to near carbon neutrality in 2008 (-1.8 Pg C/y). The impact of this MPB outbreak appears to be less dramatic than previously anticipated. The apparent fast recovery of LAI and NEP after MPB attacks is examined under the framework of ecosystem resilience which was manifested in the form of secondary overstory and understory growth and increased production of non-attacked host trees.

  12. The role of coarse woody debris in southeastern pine forests; preliminary results from a large-scale experiment.

    Energy Technology Data Exchange (ETDEWEB)

    McCay Timothy, S.; Hanula, James, L.; Loeb, Susan, C.; Lohr, Steven, M.; McMinn, James, W.; Wright-Miley. Bret, D.

    2002-08-01

    McCay, Timothy S., James L. Hanula, Susan C. Loeb, Steven M. Lohr, James W. McMinn, and Bret D. Wright-Miley. 2002. The role of coarse woody debris in southeastern pine forests; preliminary results from a large-scale experiment. 135-144. In: Proceedings of the symposium on the ecology and management of dead wood in western forests. 1999 November 2-4; Reno, NV. Gen. Tech. Rep. PSW-GTR-181. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture 949 p. ABSTRACT: We initiated a long-term experiment involving manipulation of coarse woody debris (CWD) at the Savannah River National Environmental Research Park in the upper Coastal Plain of South Carolina. Each of four 9.3-ha plots in each of four blocks was subject to one of the following treatments: removal of all snags and fallen logs, removal of fallen logs only, felling and girdling to simulate a catastrophic pulse of CWD, and control. Removal treatments were applied in 1996, and the felling or snag-creation treatment will be applied in 2000-2001. Monitoring of invertebrate, herptile, avian, and mammalian assemblages and CWD dynamics began immediately after CWD removal and continues through the present. Removal treatments resulted in a fivefold to tenfold reduction in CWD abundance. To date, significant differences among treatments have only been detected for a few animal taxa. However, preliminary results underscore the benefits of large-scale experiments. This experiment allowed unambiguous tests of hypotheses regarding the effect of CWD abundance on fauna. Coupled with studies of habitat use and trophic interactions, the experimental approach may result in stronger inferences regarding the function of CWD than results obtained through natural history observation or uncontrolled correlative studies.

  13. Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre occidental Mexico

    OpenAIRE

    Lammertink, J.M.; Rojas-Tome, J.A.; Casillas-Orona, F.M.; Otto, R.L.

    1996-01-01

    The pine-oak forests of the Sierra Madre Occidental, a mountain range in NW Mexico, have recently been recognized as an area of high endemism and biodiversity. Selective logging threatens three bird species endemic to this habitat, who depend on standing dead trees (snags). This report is based on an 11 month field survey that aimed to locate oldgrowth remnants and to assess the status of the endemic birds. Old-growth is defined here as a forest that has never been logged mechanically. Old-gr...

  14. Snag characteristics and dynamics following natural and artificially induced mortality in a managed loblolly pine forest

    Energy Technology Data Exchange (ETDEWEB)

    Zarnoch, Stanley J.; Vukovich, Mark A.; Kilgo, John C.; Blake, John I.

    2013-09-01

    A 14-year study of snag characteristics was established in 41- to 44-year old loblolly pine (Pinus taeda L.) stands in southeastern USA. During the initial 5.5 years, no stand manipulation or unusually high-mortality events occurred. Afterwards, three treatments were applied consisting of trees thinned and removed, trees felled and not removed, and artificial creation of snags produced by girdling and herbicide injection. The thinned treatments were designed to maintain the same live canopy density as the snag-created treatment, disregarding snags that remained standing.We monitored snag height, diameter, density, volume, and bark percentage; the number of cavities was monitored in natural snags only. During the first 5.5 years, recruitment and loss rates were stable, resulting in a stable snag population. Large snags (≥25 cm diameter) were common, but subcanopy small snags (10 to <25 cm diameter) dominated numerically. Large natural snags survived (90% quantile) significantly longer (6.0–9.4 years) than smaller snags (4.4–6.9 years). Large artificial snags persisted the longest (11.8 years). Cavities in natural snags developed within 3 years following tree death. The mean number of cavities per snag was five times greater in large versus small snags and large snags were more likely to have multiple cavities, emphasizing the importance of mature pine stands for cavity-dependent wildlife species.

  15. Hydro-ecological controls on dissolved carbon dynamics in groundwater and export to streams in a temperate pine forest

    Science.gov (United States)

    Deirmendjian, Loris; Loustau, Denis; Augusto, Laurent; Lafont, Sébastien; Chipeaux, Christophe; Poirier, Dominique; Abril, Gwenaël

    2018-02-01

    We studied the export of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) from forested shallow groundwater to first-order streams, based on groundwater and surface water sampling and hydrological data. The selected watershed was particularly convenient for such study, with a very low slope, with pine forest growing on sandy permeable podzol and with hydrology occurring exclusively through drainage of shallow groundwater (no surface runoff). A forest plot was instrumented for continuous eddy covariance measurements of precipitation, evapotranspiration, and net ecosystem exchanges of sensible and latent heat fluxes as well as CO2 fluxes. Shallow groundwater was sampled with three piezometers located in different plots, and surface waters were sampled in six first-order streams; river discharge and drainage were modeled based on four gauging stations. On a monthly basis and on the plot scale, we found a good consistency between precipitation on the one hand and the sum of evapotranspiration, shallow groundwater storage and drainage on the other hand. DOC and DIC stocks in groundwater and exports to first-order streams varied drastically during the hydrological cycle, in relation with water table depth and amplitude. In the groundwater, DOC concentrations were maximal in winter when the water table reached the superficial organic-rich layer of the soil. In contrast, DIC (in majority excess CO2) in groundwater showed maximum concentrations at low water table during late summer, concomitant with heterotrophic conditions of the forest plot. Our data also suggest that a large part of the DOC mobilized at high water table was mineralized to DIC during the following months within the groundwater itself. In first-order streams, DOC and DIC followed an opposed seasonal trend similar to groundwater but with lower concentrations. On an annual basis, leaching of carbon to streams occurred as DIC and DOC in similar proportion, but DOC export occurred in

  16. Hydro-ecological controls on dissolved carbon dynamics in groundwater and export to streams in a temperate pine forest

    Directory of Open Access Journals (Sweden)

    L. Deirmendjian

    2018-02-01

    Full Text Available We studied the export of dissolved inorganic carbon (DIC and dissolved organic carbon (DOC from forested shallow groundwater to first-order streams, based on groundwater and surface water sampling and hydrological data. The selected watershed was particularly convenient for such study, with a very low slope, with pine forest growing on sandy permeable podzol and with hydrology occurring exclusively through drainage of shallow groundwater (no surface runoff. A forest plot was instrumented for continuous eddy covariance measurements of precipitation, evapotranspiration, and net ecosystem exchanges of sensible and latent heat fluxes as well as CO2 fluxes. Shallow groundwater was sampled with three piezometers located in different plots, and surface waters were sampled in six first-order streams; river discharge and drainage were modeled based on four gauging stations. On a monthly basis and on the plot scale, we found a good consistency between precipitation on the one hand and the sum of evapotranspiration, shallow groundwater storage and drainage on the other hand. DOC and DIC stocks in groundwater and exports to first-order streams varied drastically during the hydrological cycle, in relation with water table depth and amplitude. In the groundwater, DOC concentrations were maximal in winter when the water table reached the superficial organic-rich layer of the soil. In contrast, DIC (in majority excess CO2 in groundwater showed maximum concentrations at low water table during late summer, concomitant with heterotrophic conditions of the forest plot. Our data also suggest that a large part of the DOC mobilized at high water table was mineralized to DIC during the following months within the groundwater itself. In first-order streams, DOC and DIC followed an opposed seasonal trend similar to groundwater but with lower concentrations. On an annual basis, leaching of carbon to streams occurred as DIC and DOC in similar proportion, but DOC export

  17. Soil C and N storage and microbial biomass in US southern pine forests: Influence of forest management

    Science.gov (United States)

    J.A. Foote; T.W. Boutton; D.A. Scott

    2015-01-01

    Land management practices have strong potential to modify the biogeochemistry of forest soils, with implications for the long-term sustainability and productivity of forestlands. The Long-Term Soil Productivity (LTSP) program, a network of 62 sites across the USA and Canada, was initiated to address concerns over possible losses of soil productivity due to soil...

  18. [Simulation of carbon cycle in Qianyanzhou artificial masson pine forest ecosystem and sensitivity analysis of model parameters].

    Science.gov (United States)

    Wang, Yuan; Zhang, Na; Yu, Gui-rui

    2010-07-01

    By using modified carbon-water cycle model EPPML (ecosystem productivity process model for landscape), the carbon absorption and respiration in Qianyanzhou artificial masson pine forest ecosystem in 2003 and 2004 were simulated, and the sensitivity of the model parameters was analyzed. The results showed that EPPML could effectively simulate the carbon cycle process of this ecosystem. The simulated annual values and the seasonal variations of gross primary productivity (GPP), net ecosystem productivity (NEP), and ecosystem respiration (Re) not only fitted well with the measured data, but also reflected the major impacts of extreme weather on carbon flows. The artificial masson pine forest ecosystem in Qianyanzhou was a strong carbon sink in both 2003 and 2004. Due to the coupling of high temperature and severe drought in the growth season in 2003, the carbon absorption in 2003 was lower than that in 2004. The annual NEP in 2003 and 2004 was 481.8 and 516.6 g C x m(-2) x a(-1), respectively. The key climatic factors giving important impacts on the seasonal variations of carbon cycle were solar radiation during early growth season, drought during peak growth season, and precipitation during post-peak growth season. Autotrophic respiration (Ra) and net primary productivity (NPP) had the similar seasonal variations. Soil heterotrophic respiration (Rh) was mainly affected by soil temperature at yearly scale, and by soil water content at monthly scale. During wet growth season, the higher the soil water content, the lower the Rh was; during dry growth season, the higher the precipitation during the earlier two months, the higher the Rh was. The maximum RuBP carboxylation rate at 25 degrees C (Vm25), specific leaf area (SLA), maximum leaf nitrogen content (LNm), average leaf nitrogen content (LN), and conversion coefficient of biomass to carbon (C/B) had the greatest influence on annual NEP. Different carbon cycle process could have different responses to sensitive

  19. Response of brown-headed cowbirds and three host species to thinning treatments in low-elevation ponderosa pine forests along the northern Colorado Front Range

    Science.gov (United States)

    Keeley, W.H.; Germaine, Stephen S.; Stanley, Thomas R.; Spaulding, Sarah A.; Wanner, C.E.

    2013-01-01

    Thinning ponderosa pine (Pinus ponderosa) forests to achieve desired ecological conditions remains a priority in the North American west. In addition to reducing the risk of high-severity wildfires in unwanted areas, stand thinning may increase wildlife and plant diversity and provide increased opportunity for seedling recruitment. We initiated conservative (i.e. minimal removal of trees) ponderosa stand thinning treatments with the goals of reducing fire risk and improving habitat conditions for native wildlife and flora. We then compared site occupancy of brown-headed cowbirds (Molothrus ater), chipping sparrows (Spizella passerina), plumbeous vireos (Vireo plumbeus), and western wood-pewees (Contopus sordidulus) in thinned and unthinned (i.e., control) forest stands from 2007 to 2009. Survey stations located in thinned stands had 64% fewer trees/ha, 25% less canopy cover, and 23% less basal area than stations in control stands. Occupancy by all three host species was negatively associated with tree density, suggesting that these species respond favorably to forest thinning treatments in ponderosa pine forests. We also encountered plumbeous vireos more frequently in plots closer to an ecotonal (forest/grassland) edge, an association that may increase their susceptibility to edge-specialist, brood parasites like brown-headed cowbirds. Occupancy of brown-headed cowbirds was not related to forest metrics but was related to occupancy by plumbeous vireos and the other host species in aggregate, supporting previous reports on the affiliation between these species. Forest management practices that promote heterogeneity in forest stand structure may benefit songbird populations in our area, but these treatments may also confer costs associated with increased cowbird occupancy. Further research is required to understand more on the complex relationships between occupancy of cowbirds and host species, and between cowbird occupancy and realized rates of nest parasitism.

  20. Time trends in the levels and patterns of polycyclic aromatic hydrocarbons (PAHs) in pine bark, litter, and soil after a forest fire.

    Science.gov (United States)

    Choi, Sung-Deuk

    2014-02-01

    Forest fires are known as an important natural source of polycyclic aromatic hydrocarbons (PAHs), but time trends of PAH levels and patterns in various environmental compartments after forest fires have not been thoroughly studied yet. In this study, 16 US-EPA priority PAHs were analyzed for pine bark, litter, and soil samples collected one, three, five, and seven months after a forest fire in Pohang, South Korea. At the first sampling event, the highest levels of ∑16 PAHs were measured for the three types of samples (pine bark: 5,920 ng/g, litter: 1,540 ng/g, and soil: 133 ng/g). Thereafter, there were apparent decreasing trends in PAH levels; the control samples showed the lowest levels (pine bark: 124 ng/g, litter: 75 ng/g, and soil: 26 ng/g). The levels of PAHs in the litter and soil samples normalized by organic carbon (OC) fractions also showed decreasing trends, indicating a direct influence of the forest fire. Among the 16 target PAHs, naphthalene was a dominant compound for all types of samples. Light PAHs with 2-4 rings significantly contributed to the total concentration, and their contribution decreased in the course of time. Runoff by heavy precipitation, evaporation, and degradation of PAHs in the summer were probably the main reasons for the observed time trends. The results of principal component analysis (PCA) and diagnostic ratio also supported that the forest fire was indeed an important source of PAHs in the study area. © 2013.

  1. Multivariate Analysis of Some Pine Forested Areas of Azad Kashmir-Pakistan

    International Nuclear Information System (INIS)

    Bokhari, T.Z.; Liu, Y.; Li, Q.; Malik, S.A.; Ahmed, M.; Siddiqui, M.F.; Khan, Z.U.

    2016-01-01

    Floristic composition and communities in Azad Kashmir area of Pakistan were studied by using multivariate analysis. Quantitative sampling from thirty one sites was carried out in different coniferous forests of Azad Kashmir in order to analyze the effects of past earthquakes and landslides on vegetation of these areas. Though coniferous forests were highly disturbed either naturally or anthropogenic activities, therefore sampling was preferred to those forests which were near fault line. Trees were sampled using Point Centered Quarter (PCQ) method. Results of cluster analysis (using Ward's method) yielded six groups dominated by different conifer species. Group I and V were dominated by Pinus wallichiana while this species was co-dominant in group III. Other groups showed the dominance of different conifer species i.e. Cedrus deodara, Pinus roxburghii, Picea smithiana and Abies pindrow. Both the cluster analysis and ordination techniques (by two dimensional non-metric multidimensional scaling) classify and ordinate the structure of various groups indicating interrelationship among different species. The groups of trees were readily be superimposed on NMS ordination axes; they were well classified and well separated out in ordination. The present research revealed that these forests had diverse and asymmetric structure due to natural anthropogenic disturbances and overgrazing, which were key factors in addition to natural disturbances. However, some of the forests showed considerably stable structure due to less human interference. (author)

  2. Occurrence of Porodaedalea pini (Brot.: Fr. Murr. in pine forests of the lake district in south-western Turkey

    Directory of Open Access Journals (Sweden)

    A. Lehtijärvi

    2007-12-01

    Full Text Available The occurrence of basidiocarps of the white rot fungus Porodaedalea (Phellinus pini on Pinus nigra subsp. pallasiana and P. brutia was investigated in six stands, covering a total land area of some 650 hectares, in Isparta province of the Lake District in Turkey. The height above ground of the lowermost P. pini basidiocarp was measured on each trunk. Basidiocarps of P. pini were found on thirty-eight trees, 32 P. nigra subsp. pallasiana (84.2% of the total and six P. brutia (15.8%. The breast-height diameter of P. nigra individuals with P. pini ranged from 41 to 188 cm (average 77.7 cm and that of P. brutia with P. pini from 68 to 96 cm (average 76.4 cm. Basidiocarps were mostly found on the lower part of the trunks of old trees. In addition to pathological aspects, the ecological role of the fungus in old-growth pine forests is discussed in relation to nature conservancy and biodiversity.

  3. Exploring Conservation Options in the Broad-Leaved Korean Pine Mixed Forest of the Changbai Mountain Region

    Directory of Open Access Journals (Sweden)

    Lin Ma

    2015-05-01

    Full Text Available The broad-leaved Korean pine (Pinus koraiensis mixed forest (BKPF is one of the most biodiverse zonal communities in the northern temperate zone. Changbai Mountain in northeastern China contains one of the largest BKPFs in the region. The government of China has established a network of 23 nature reserves to protect the BKPF and the species that depend on it for habitat, including the endangered Siberian tiger (Panthera tigris altaica. This study used the conservation planning software C-Plan to calculate the irreplaceability value of each unit to assess how efficiently and comprehensively the existing conservation network supports biodiversity and to identify gap areas that, if integrated into the network, would expand its protection capability. Results show a number of high-conservation-value planning units concentrated along certain ridges. The existing conservation network is structured such that the habitats of only 24 species (out of a total of 75 achieve established conservation targets. Of the other 51 species, 20 achieve less than 50% of their conservation targets. However, expanding the network to include high-conservation-value gap areas could achieve conservation targets for 64 species and could provide different degrees of protection to the other 11 species. Using C-Plan software can guide decision-making to expand the conservation network in this most precious of mountainous ecological zones.

  4. Soil respiration and photosynthetic uptake of carbon dioxide by ground-cover plants in four ages of jack pine forest

    Science.gov (United States)

    Striegl, Robert G.; Wickland, K.P.

    2001-01-01

    Soil carbon dioxide (CO2) emission (soil respiration), net CO2 exchange after photosynthetic uptake by ground-cover plants, and soil CO2 concentration versus depth below land surface were measured at four ages of jack pine (Pinus banksiana Lamb.) forest in central Saskatchewan. Soil respiration was smallest at a clear-cut site, largest in an 8-year-old stand, and decreased with stand age in 20-year-old and mature (60-75 years old) stands during May-September 1994 (12.1, 34.6, 31.5, and 24.9 mol C??m-2, respectively). Simulations of soil respiration at each stand based on continuously recorded soil temperature were within one standard deviation of measured flux for 48 of 52 measurement periods, but were 10%-30% less than linear interpolations of measured flux for the season. This was probably due to decreased soil respiration at night modeled by the temperature-flux relationships, but not documented by daytime chamber measurements. CO2 uptake by ground-cover plants ranged from 0 at the clear-cut site to 29, 25, and 9% of total growing season soil respiration at the 8-year, 20-year, and mature stands. CO2 concentrations were as great as 7150 ppmv in the upper 1 m of unsaturated zone and were proportional to measured soil respiration.

  5. Establishing Longleaf Pine Seedlings Under a Loblolly Pine Canopy (User’s Guide)

    Science.gov (United States)

    2017-02-01

    longleaf pine forests (Figure 1) for the diverse values they provide. These forests afford abundant recreational opportunities like hiking , bird...combined herbicide-fertilizer treatments that might benefit planted longleaf pine seedlings after planting. In addition to measuring longleaf pine

  6. Effects of silviculture on neotropical migratory birds in central and southeastern oak pine forests

    Science.gov (United States)

    James G. Dickson; Frank R. Thompson; Richard N. Conner; Kathleen E. Franzreb

    1993-01-01

    Avian communities that are associated with forest habitat attributes are affected by silvicultural and other stand influences. Some species have specific habitat requirements, whereas others occupy a broad range of vegetative conditions. In general, bird species richness and density are positively related to stand foliage volume and diversity. Bird density and...

  7. FireWorks curriculum featuring ponderosa, lodgepole, and whitebark pine forests

    Science.gov (United States)

    Jane Kapler Smith; Nancy E. McMurray

    2000-01-01

    FireWorks is an educational program for students in grades 1-10. The program consists of the curriculum in this report and a trunk of laboratory materials, specimens, and reference materials. It provides interactive, hands-on activities for studying fire ecology, fire behavior, and the influences of people on three fire-dependent forest types - Pinus ponderosa...

  8. Effects of variable retention harvesting on natural tree regeneration in Pinus resinosa (red pine) forests

    Science.gov (United States)

    Margaret W. Roberts; Anthony W. D' Amato; Christel C. Kern; Brian J. Palik

    2017-01-01

    Concerns over loss of ecosystem function and biodiversity in managed forests have led to the development of silvicultural approaches that meet ecological goals as well as sustain timber production. Variable Retention Harvest (VRH) practices, which maintain mature overstory trees across harvested areas, have been suggested as an approach to balance these objectives;...

  9. Effects of intensive forest management practices on insect infestation levels and loblolly pine growth

    Science.gov (United States)

    John T. Nowak; C. Wayne Berisford

    2000-01-01

    Intensive forest management practices have been shown to increase tree growth and shorten rotation time. However, they may also lead to an increased need for insect pest management because of higher infestation levels and lower action thresholds. To investigate the relationship between intensive management practices arid insect infestation, maximum growth potential...

  10. Thinning method and intensity influence long-term mortality trends in a red pine forest

    Science.gov (United States)

    Matthew D. Powers; Brian J. Palik; John B. Bradford; Shawn Fraver; Christopher R. Webster

    2010-01-01

    Tree mortality shapes forest development, but rising mortality can represent lost production or an adverse response to changing environmental conditions. Thinning represents a strategy for reducing mortality rates, but different thinning techniques and intensities could have varying impacts depending on how they alter stand structure. We analyzed trends in stand...

  11. Model Optimization Planting Pattern Agroforestry Forest Land Based on Pine Tree

    Science.gov (United States)

    Rajati, Tati

    2015-01-01

    This study aims to determine cropping patterns in class slopes 0 - 30%. The method used in this study is a description of the dynamic system approach using a software power sim. Forest areas where the research, which is a type of plant that is cultivated by the people in the study…

  12. Application of Linked Regional Scale Growth, Biogeography, and Economic Models for Southeastern United States Pine Forests

    Science.gov (United States)

    Steven G. McNulty; Jennifer A. Moore; Louis Iverson; Anantha Prasad; Robert Abt; Bryan Smith; Ge Sun; Michael Gavazzi; John Bartlett; Brian Murray; Robert A. Mickler; John D. Aber

    2000-01-01

    The southern United States produces over 50% of commercial timber harvests in the US and the demand for southern timber are likely to increase in the future. Global change is altering the physical and chemical environmental which will play a major role in determining future forest stand growth, insect and disease outbreaks, regeneration success, and distribution of...

  13. Application of linked regional scale growth, biogeography, and economic models for southeastern United States pine forests

    Science.gov (United States)

    Steven G. McNulty; Jennifer A. Moore; Louis Iverson; Anantha Prasad; Robert, et al. Abt

    2000-01-01

    The southern United States produces over 50% of commercial timber harvests in the US and the demand for southern timber are likely to increase in the future. Global change is altering the physical and chemical environmental which will play a major role in determining future forest stand growth, insect and disease outbreaks, regeneration success, and distribution of...

  14. Newtonian boreal forest ecology: The Scots pine ecosystem as an example.

    Directory of Open Access Journals (Sweden)

    Pertti Hari

    Full Text Available Isaac Newton's approach to developing theories in his book Principia Mathematica proceeds in four steps. First, he defines various concepts, second, he formulates axioms utilising the concepts, third, he mathematically analyses the behaviour of the system defined by the concepts and axioms obtaining predictions and fourth, he tests the predictions with measurements. In this study, we formulated our theory of boreal forest ecosystems, called NewtonForest, following the four steps introduced by Newton. The forest ecosystem is a complicated entity and hence we needed altogether 27 concepts to describe the material and energy flows in the metabolism of trees, ground vegetation and microbes in the soil, and to describe the regularities in tree structure. Thirtyfour axioms described the most important features in the behaviour of the forest ecosystem. We utilised numerical simulations in the analysis of the behaviour of the system resulting in clear predictions that could be tested with field data. We collected retrospective time series of diameters and heights for test material from 6 stands in southern Finland and five stands in Estonia. The numerical simulations succeeded to predict the measured diameters and heights, providing clear corroboration with our theory.

  15. Dwarf mistletoe effects on fuel loadings in ponderosa pine forests in northern Arizona

    Science.gov (United States)

    Chad Hoffman; Robert Mathiasen; Carolyn Hull Sieg

    2007-01-01

    Southwestern dwarf mistletoe (Arceuthobium vaginatum (Willd.) J. Presl ssp. cryptopodum) infests about 0.9 million ha in the southwestern United States. Several studies suggest that dwarf mistletoes affect forest fuels and fire behavior; however, few studies have quantified these effects. We compared surface fuel loadings and...

  16. Ponderosa pine, mixed conifer, and spruce-fir forests [Chapter 2

    Science.gov (United States)

    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. Pro-B selection method for uneven-aged management of longleaf pine forests

    Science.gov (United States)

    Dale G. Brockway; Edward F. Loewenstein; Kenneth W. Outcalt

    2015-01-01

    Interest in uneven-aged silviculture has increased since advent of ecosystem management programs, which place greater emphasis on ecological values and ecosystem services while also harvesting timber from the forest. However, traditional uneven-aged approaches (e.g., BDq) are often criticized as too complex, costly, and requiring highly-trained staff. The Proportional-...

  18. Use of Glyphosate and Imazapyr for Cogongrass (Imperata cylindrica) management in southern pine forests

    Science.gov (United States)

    Patrick J. Minogue; James H. Miller; Dwight K. Lauer

    2012-01-01

    Cogongrass (Imperata cylindrica [L.] P. Beauv. var. major [Nees] C.E. Hubb) is one of the most invasive perennial grasses worldwide and has progressively infested managed and natural habitats in the mid-South over the past 100 years. To extend past research toward the goal of eradication on forested sites, we tested the most effective herbicides (glyphosate and...

  19. Influencing factors on vegetative cogongrass spread into pine forests on the Mississippi gulf coast

    Science.gov (United States)

    Jon D. Prevost; Donald L. Grebner; Jeanne C. Jones; Stephen C. Grado; Keith L. Belli; John D. Byrd

    2010-01-01

    Cogongrass [Imperata cylindrical (L.) Beauv.] is an invasive species that is spreading throughout forested ecosystems across the Southeastern United States. A field experiment was conducted in Hancock County, MS to determine if mid-rotation mechanical disturbance increased the rate of growth and spread of roadside cogongrass patches into adjacent...

  20. Utilization of forest slash to sequester carbon in loblolly pine plantations in the lower coastal plain

    Science.gov (United States)

    F. Sanchez; E.A. Carter; W. Edwards

    2002-01-01

    Soil-organic matter (SOM) is a complex array of components including soil fauna and flora at different stages of decomposition (Berg et al., 1982). Its concentration in soils can vary from 0.5% in mineral soils to almost 100% in peat soils (Brady, 1974). Organic matter (OM) in the surface mineral soil is considered a major determinant of forest ecosystem productivity...

  1. Diurnal roosts of male evening bats (Nycticeius humeralis) in diversely managed pine-hardwood forests

    Science.gov (United States)

    Roger W. Perry; Ronald E. Thill

    2008-01-01

    We examined attributes of 45 roost sites used by 17 adult male evening bats (Nycticeius humeralis) in a diverse forested landscape within the Ouachita Mountains, Arkansas. Bats roosted in a diverse array of substrates, including live or dead Pinus echinata $15 cm diam at breast height (29% of roosts) and small (,10 cm) understory or midstory...

  2. Tree Mortality following Prescribed Fire and a Storm Surge Event in Slash Pine (Pinus elliottii var. densa) Forests in the Florida Keys, USA

    International Nuclear Information System (INIS)

    Sah, J.P.; Ross, M.S.; Ross, M.S.; Ogurcak, D.E.; Snyder, J.R.

    2010-01-01

    In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on post fire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with under story type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated with tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pine lands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase.

  3. Blister rust control in the management of western white pine

    Science.gov (United States)

    Kenneth P. Davis; Virgil D. Moss

    1940-01-01

    The forest industry of the western white pine region depends on the production of white pine as a major species on about 2,670,000 acres of commercial forest land. Continued production of this species and maintenance of the forest industry at anything approaching its present level is impossible unless the white pine blister rust is controlled. Existing merchantable...

  4. Terrestrial lichen response to partial cutting in lodgepole pine forests on caribou winter range in west-central British Columbia

    Directory of Open Access Journals (Sweden)

    Michaela J. Waterhouse

    2011-09-01

    Full Text Available In west-central British Columbia, terrestrial lichens located in older, lodgepole pine (Pinus contorta forests are important winter forage for woodland caribou (Rangifer tarandus caribou. Clearcut harvesting effectively removes winter forage habitat for decades, so management approaches based on partial cutting were designed to maintain continuous lichen-bearing habitat for caribou. This study tested a group selection system, based on removal of 33% of the forest every 80 years in small openings (15 m diameter, and two irregular shelterwood treatments (whole-tree and stem-only harvesting methods where 50% of the stand area is cut every 70 years in 20 to 30 m diameter openings. The abundance of common terrestrial lichens among the partial cutting and no-harvest treatments was compared across five replicate blocks, pre-harvest (1995 and post-harvest (1998, 2000 and 2004. The initial loss of preferred forage lichens (Cladonia, Cladina, Cetraria and Stereocaulon was similar among harvesting treatments, but there was greater reduction in these lichens in the openings than in the residual forest. After eight years, forage lichens in the group selection treatment recovered to pre-harvest amounts, while lichen in the shelterwood treatments steadily increased from 49 to 57% in 1998 to about 70% of pre-harvest amounts in 2004. Although not part of the randomized block design, there was substantially less lichen in three adjacent clearcut blocks than in the partial cuts. Regression analysis pre- and post-harvest indicated that increased cover of trees, shrubs, herbs, woody debris and logging slash corresponded with decreased forage lichen abundance. In the short-term, forestry activities that minimize inputs of woody debris, control herb and shrub development, and moderate the changes in light and temperatures associated with canopy removal will lessen the impact on lichen. Implementation of stand level prescriptions is only one aspect of caribou habitat

  5. Local and landscape-scale biotic correlates of mistletoe distribution in Mediterranean pine forests

    Energy Technology Data Exchange (ETDEWEB)

    Roura-Pascual, N.; Brotons, L.; Garcia, D.; Zamora, R.; Caceres, M. de

    2012-11-01

    The study of the spatial patterns of species allows the examination of hypotheses on the most plausible ecological processes and factors determining their distribution. To investigate the determinants of parasite species on Mediterranean forests at regional scales, occurrence data of the European Misletoe (Viscum album) in Catalonia (NE Iberian Peninsula) were extracted from forest inventory data and combined with different types of explanatory variables by means of generalized linear mixed models. The presence of mistletoes in stands of Pinus halepensis seems to be determined by multiple factors (climatic conditions, and characteristics of the host tree and landscape structure) operating at different spatial scales, with the availability of orchards of Olea europaea in the surroundings playing a relevant role. These results suggest that host quality and landscape structure are important mediators of plant-plant and plant-animal interactions and, therefore, management of mistletoe populations should be conducted at both local (i.e. clearing of infected host trees) and landscape scales (e.g. controlling the availability of nutrient-rich food sources that attract bird dispersers). Research and management at landscape-scales are necessary to anticipate the negative consequence of land-use changes in Mediterranean forests. (Author) 38 refs.

  6. High Tonnage Forest Biomass Production Systems from Southern Pine Energy Plantations

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Steve [Auburn Univ., AL (United States); McDonald, Timothy [Auburn Univ., AL (United States); Fasina, Oladiran [Auburn Univ., AL (United States); Gallagher, Tom [Auburn Univ., AL (United States); Smidt, Mathew [Auburn Univ., AL (United States); Mitchell, Dana [US Dept. of Agriculture (USDA) Forest Service, Washington, DC (United States); Klepac, John [US Dept. of Agriculture (USDA) Forest Service, Washington, DC (United States); Thompson, Jason [US Dept. of Agriculture (USDA) Forest Service, Washington, DC (United States); Sprinkle, Wes [US Dept. of Agriculture (USDA) Forest Service, Washington, DC (United States); Carter, Emily [US Dept. of Agriculture (USDA) Forest Service, Washington, DC (United States); Grace, Johnny [US Dept. of Agriculture (USDA) Forest Service, Washington, DC (United States); Rummer, Robert [US Dept. of Agriculture (USDA) Forest Service, Washington, DC (United States); Corley, Frank [Corley Land Services, Chapman, AL (United States); Somerville, Grant [Tigercat, Brantford, ON (Canada)

    2014-09-01

    /PMH versus 68 gt/PMH for a comparable conventional system. Machine rate costs for felling and skidding were $2.31/gt and $3.72/gt for the high tonnage, and conventional systems, respectively. However, the most significant result of the project is that the high tonnage system was shown to be relatively insensitive to tree size. This ability to maintain felling and skidding productivity and cost as tree size decreases is a breakthrough in harvesting systems for southern pine plantations. The concept of transpirational drying of woody biomass was tested at an industrial scale at multiple locations during this project. Felled trees were allowed to dry in two scenarios: 1) in bunches where they were felled, and 2) in roadside piles. Although the wood piled in large piles at roadside did experience drying, the wood left in bunches experienced a greater moisture reduction. Drying times of 72 days in the late summer resulted in mean wood moisture content of 26% for skidder bunches and 39% for the large pile at roadside as compared to moisture contents of 55% to 58% for freshly cut trees. An existing whole-tree chipper, Precision 2675, was modified to allow production of chips smaller than the traditional pulp size chip (i.e. “microchips”). Feed rates and knife placements were retained in the new design, while additional pockets were incorporated in the chipper disk to allow the attachment of either four knives for pulp chips or eight knives for microchips. This design facilitated switching between the energy and pulp chip product options at relatively low expense (about ½ day downtime). Chipping of whole-trees into pulp chips and microchips with the Precision 2675 disk chipper resulted in average productivities of 79.5 gt/PMH and 70.7 gt/PMH, respectively. Production rates of the chipper were lower when producing microchips by about 10% relative to producing pulp chips, but rates were similar to those achievable when making clean pulp chips. Particle size analysis for clean

  7. Drought-related tree mortality in drought-resistant semi-arid Aleppo pine forest

    Science.gov (United States)

    Preisler, Yakir; Grünzweig, José M.; Rotenberg, Eyal; Rohatyn, Shani; Yakir, Dan

    2014-05-01

    The frequency and intensity of drought events are expected to increase as part of global climate change. In fact, drought related tree mortality had become a widespread phenomenon in forests around the globe in the past decades. This study was conducted at the Yatir FLUXNET site, located in a 45 years old Pinus halepensis dominated forest that successfully sustained low mean annual precipitation (276mm) and extended seasonal droughts (up to 340 days between rain events). However, five recent non-consecutive drought years led to enhanced tree mortality in 2010 (5-10% of the forest population, which was not observed hitherto). The Tree mortality was characterized by patchiness, showing forest zones with either >80% mortality or no mortality at all. Areas of healthy trees were associated with deeper root distribution and increased stoniness (soil pockets & cracks). To help identify possible causes of the increased mortality and its patterns, four tree stress levels were identified based on visual appearance, and studied in more detail. This included examining from spring 2011 to summer 2013 the local trees density, root distribution, annual growth rings, needle length and chlorophyll content, rates of leaf gas exchange, and branch predawn water potential. Tree phenotypic stress level correlated with the leaf predawn water potential (-1.8 and -3.0 in healthy and stressed trees, respectively), which likely reflected tree-scale water availability. These below ground characteristics were also associated, in turn, with higher rate of assimilation (3.5 and 0.8 μmol CO2 m-2s1 in healthy and stress trees, respectively), longer needles (8.2cm and 3.4 cm in healthy and stressed trees, respectively). Annual ring widths showed differences between stress classes, with stressed trees showing 30% narrower rings on average than unstressed trees. Notably, decline in annual ring widths could be identified in currently dead or severely stressed trees 15-20 years prior to mortality or

  8. Soil carbon dynamics in Scots pine forests at the Sistema Central of Spain (Sierra de Guadarrama)

    OpenAIRE

    Ortiz Oñate, Carlos

    2017-01-01

    Los suelos forestales son clave en el cambio global por el carbono (C) que acumulan y por su capacidad de sumidero de C. Además de factores abióticos como el clima y las propiedades del suelo, la capacidad de los suelos para almacenar C está influenciada por el uso del suelo, los cambios en el uso del suelo y la ordenación forestal, que en última instancia pueden modificar las condiciones microclicámitas, la calidad y cantidad de los residuos vegetales que se incorporan al suelo, así como la ...

  9. Soil microbiological properties and enzymatic activities of long-term post-fire recovery in dry and semiarid Aleppo pine (Pinus halepensis M.) forest stands

    Science.gov (United States)

    Hedo, J.; Lucas-Borja, M. E.; Wic, C.; Andrés-Abellán, M.; de Las Heras, J.

    2015-02-01

    Wildfires affecting forest ecosystems and post-fire silvicultural treatments may cause considerable changes in soil properties. The capacity of different microbial groups to recolonise soil after disturbances is crucial for proper soil functioning. The aim of this work was to investigate some microbial soil properties and enzyme activities in semiarid and dry Aleppo pine (Pinus halepensis M.) forest stands. Different plots affected by a wildfire event 17 years ago without or with post-fire silvicultural treatments 5 years after the fire event were selected. A mature Aleppo pine stand, unaffected by wildfire and not thinned was used as a control. Physicochemical soil properties (soil texture, pH, carbonates, organic matter, electrical conductivity, total N and P), soil enzymes (urease, phosphatase, β-glucosidase and dehydrogenase activities), soil respiration and soil microbial biomass carbon were analysed in the selected forests areas and plots. The main finding was that long time after this fire event produces no differences in the microbiological soil properties and enzyme activities of soil after comparing burned and thinned, burned and not thinned, and mature plots. Moreover, significant site variation was generally seen in soil enzyme activities and microbiological parameters. We conclude that total vegetation recovery normalises post-fire soil microbial parameters, and that wildfire and post-fire silvicultural treatments are not significant factors affecting soil properties after 17 years.

  10. Drought stress, growth and nonstructural carbohydrate dynamics of pine trees in a semi-arid forest.

    Science.gov (United States)

    Klein, Tamir; Hoch, Günter; Yakir, Dan; Körner, Christian

    2014-09-01

    In trees exposed to prolonged drought, both carbon uptake (C source) and growth (C sink) typically decrease. This correlation raises two important questions: (i) to what degree is tree growth limited by C availability; and (ii) is growth limited by concurrent C storage (e.g., as nonstructural carbohydrates, NSC)? To test the relationships between drought, growth and C reserves, we monitored the changes in NSC levels and constructed stem growth chronologies of mature Pinus halepensis Miller trees of three drought stress levels growing in Yatir forest, Israel, at the dry distribution limit of forests. Moderately stressed and stressed trees showed 34 and 14% of the stem growth, 71 and 31% of the sap flux density, and 79 and 66% of the final needle length of healthy trees in 2012. In spite of these large reductions in growth and sap flow, both starch and soluble sugar concentrations in the branches of these trees were similar in all trees throughout the dry season (2-4% dry mass). At the same time, the root starch concentrations of moderately stressed and stressed trees were 47 and 58% of those of healthy trees, but never drought there is more than one way for a tree to maintain a positive C balance. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Effects of forest fire on soil nutrients in Turkish pine (Pinus brutia, Ten) ecosystems.

    Science.gov (United States)

    Yildiz, Oktay; Esen, Derya; Sarginci, Murat; Toprak, Bulent

    2010-01-01

    Fire is a long-standing and poorly understood component of the Mediterranean forestlands in Turkey. Fire can alter plant composition, destroy biomass, alter soil physical and chemical properties and reduce soil nutrient pools. However fire can also promote productivity of certain ecosystems by mineralizing soil nutrients and promoting fast growing nitrogen fixing plant species. Fire effects on soils and ecosystems in Turkey and Mediterranean regions are not well understood. This study uses a retrospective space-for-time substitution to study soil macro-nutrient changes on sites which were burned at different times during the last 8 years. The study sites are in the Fethiye Forest Management Directorate in the western Mediterranean Sea region of Turkey. Our samples show 40% less Soil C, and cation exchange capacity (CEC) at 0-20 cm soil depth two weeks after the fire. Soil C and CEC appear to recover to pre-fire level in one year. Concentrations of Mg were significantly lower on new-burn sites, but returned to pre-fire levels in one year. Total soil N concentrations one and two years after fire were 90% higher than other sites, and total P was 9 times higher on new-burn site than averages from other sites. Some implications of these results for forest managers are discussed.

  12. Sulphur isotopes as tracers of the influence of a coal-fired power plant on a Scots pine forest in Catalonia (NE Spain)

    Science.gov (United States)

    Puig, R.; Àvila, A.; Soler, A.

    Stable sulphur isotopes and major ionic composition were analysed in precipitation and throughfall samples from a Scots pine ( Pinus sylvestris, L.) forest near the Cercs coal-fired power plant (Catalonia, NE Spain). The purpose of the study was to determine the main sources of sulphur deposition on this pine forest. Sulphur isotope measurements from the SO 2 power plant stack emissions were used to identify the isotopic signature of this source. Net throughfall fluxes of sulphur (26.1 kg S ha 1 yr -1) and nitrogen (16.3 kg N ha -1 yr -1) were higher—5-25 times higher for S and 5-15 times for N—at this site than in other forests in Catalonia. Sulphur isotope analysis confirmed that the net throughfall fluxes of sulphur were mostly due to the dry deposition of the SO 2 power plant emissions onto the pine canopies. Two potential atmospheric end-members were distinguished: regional background rainwater (δ 34S=+7.2‰) and power plant emissions (δ 34S=-2.8‰). By applying a two-component sulphur isotope mixing model, we found that during periods of low power plant activity (⩽10 emission h day -1), 62% of the throughfall sulphate could be attributed to the power plant emissions. At higher activity periods (⩾14 emission h day -1), this contribution rose to 73%. Although power plant contribution to bulk deposition was lower in both cases (34% and 45%), the possible influence of sulphate coming with long-range transport events from the polluted areas in the Mediterranean basin (δ 34S≈0‰) was not discarded.

  13. Herbivory and climate interact serially to control monoterpene emissions from pinyon pine forests.

    Science.gov (United States)

    Trowbridge, Amy M; Daly, Ryan W; Helmig, Detlev; Stoy, Paul C; Monson, Russell K

    2014-06-01

    The emission of volatile monoterpenes from coniferous trees impacts the oxidative state of the troposphere and multi-trophic signaling between plants and animals. Previous laboratory studies have revealed that climate anomalies and herbivory alter the rate of tree monoterpene emissions. However, no studies to date have been conducted to test these relations in situ. We conducted a two-year field experiment at two semiarid sites dominated by pinyon pine (Pinus edulis) during outbreaks of a specialist herbivore, the southwestern tiger moth (Lophocampa ingens: Arctiidae). We discovered that during the early spring, when herbivory rates were highest, monoterpene emission rates were approximately two to six times higher from undamaged needles on damaged trees, with this increase in emissions due to alpha-pinene, beta-pinene, and camphene at both sites. During mid-summer, emission rates did not differ between previously damaged and undamaged trees at the site on the Western Slope of the Rocky Mountains, but rather tracked changes in the temperature and precipitation regime characteristic of the region. As the mid-summer drought progressed at the Eastern Slope site, emission rates were low, but differences between previously damaged and undamaged trees were not statistically significant. Despite no difference in emissions, mid-summer tissue monoterpene concentrations were significantly lower in previously damaged trees at both sites. With the onset of monsoon rains during late summer, emission rates from previously damaged trees increased to levels higher than those of undamaged trees despite the lack of herbivory. We conclude that (1) herbivory systemically increases the flux of terpenes to the atmosphere during the spring, (2) drought overrides the effect of past herbivory as the primary control over emissions during the mid-summer, and (3) a release from drought and the onset of late-summer rains is correlated with a secondary increase in emissions, particularly from

  14. Spatial and temporal corroboration of a fire-scar-based fire history in a frequently burned ponderosa pine forest.

    Science.gov (United States)

    Farris, Calvin A; Baisan, Christopher H; Falk, Donald A; Yool, Stephen R; Swetnam, Thomas W

    2010-09-01

    Fire scars are used widely to reconstruct historical fire regime parameters in forests around the world. Because fire scars provide incomplete records of past fire occurrence at discrete points in space, inferences must be made to reconstruct fire frequency and extent across landscapes using spatial networks of fire-scar samples. Assessing the relative accuracy of fire-scar fire history reconstructions has been hampered due to a lack of empirical comparisons with independent fire history data sources. We carried out such a comparison in a 2780-ha ponderosa pine forest on Mica Mountain in southern Arizona (USA) for the time period 1937-2000. Using documentary records of fire perimeter maps and ignition locations, we compared reconstructions of key spatial and temporal fire regime parameters developed from documentary fire maps and independently collected fire-scar data (n = 60 plots). We found that fire-scar data provided spatially representative and complete inventories of all major fire years (> 100 ha) in the study area but failed to detect most small fires. There was a strong linear relationship between the percentage of samples recording fire scars in a given year (i.e., fire-scar synchrony) and total area burned for that year (y = 0.0003x + 0.0087, r2 = 0.96). There was also strong spatial coherence between cumulative fire frequency maps interpolated from fire-scar data and ground-mapped fire perimeters. Widely reported fire frequency summary statistics varied little between fire history data sets: fire-scar natural fire rotations (NFR) differed by or = 25% of study area burned) were identical between data sets (25.5 yr); fire-scar MFIs for all fire years differed by 1.2 yr from documentary records. The known seasonal timing of past fires based on documentary records was furthermore reconstructed accurately by observing intra-annual ring position of fire scars and using knowledge of tree-ring growth phenology in the Southwest. Our results demonstrate clearly

  15. N2O, NO and CH4 exchange, and microbial N turnover over a Mediterranean pine forest soil

    Directory of Open Access Journals (Sweden)

    P. Rosenkranz

    2006-01-01

    Full Text Available Trace gas exchange of N2O, NO/NO2 and CH4 between soil and the atmosphere was measured in a typical Mediterranean pine (Pinus pinaster forest during two intensive field campaigns in spring and autumn 2003. Furthermore, gross and net turnover rates of N mineralization and nitrification as well as soil profiles of N2O and CH4 concentrations were determined. For both seasons a weak but significant N2O uptake from the atmosphere into the soil was observed. During the unusually dry and hot spring mean N2O uptake was −4.32 µg N m-2 h-1, whereas during the wet and mild autumn mean N2O uptake was −7.85 µg N m-2 h-1. The observed N2O uptake into the soil was linked to the very low availability of inorganic nitrogen at the study site. Organic layer gross N mineralization decreased from 5.06 mg N kg-1 SDW d-1 in springtime to 2.68 mg N kg-1 SDW d-1 in autumn. Mean NO emission rates were significantly higher in springtime (9.94 µg N m-2 h-1 than in autumn (1.43 µg N m-2 h-1. A significant positive correlation between NO emission rates and gross N mineralization as well as nitrification rates was found. The negative correlation between NO emissions and soil moisture was explained with a stimulation of aerobic NO uptake under N limiting conditions. Since NO2 deposition was continuously higher than NO emission rates the examined forest soil functioned as a net NOx sink. Observed mean net CH4 uptake rates were in spring significantly higher (−73.34 µg C m-2 h-1 than in autumn (−59.67 µg C m-2 h-1. Changes in CH4 uptake rates were strongly negatively correlated with changes in soil moisture. The N2O and CH4 concentrations in different soil depths revealed the organic layer and the upper 0.1 m of mineral soil as the most important soil horizons for N2O and CH4 consumption.

  16. Modeling Forest Structural Parameters in the Mediterranean Pines of Central Spain using QuickBird-2 Imagery and Classification and Regression Tree Analysis (CART

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    José A. Delgado

    2012-01-01

    Full Text Available Forest structural parameters such as quadratic mean diameter, basal area, and number of trees per unit area are important for the assessment of wood volume and biomass and represent key forest inventory attributes. Forest inventory information is required to support sustainable management, carbon accounting, and policy development activities. Digital image processing of remotely sensed imagery is increasingly utilized to assist traditional, more manual, methods in the estimation of forest structural attributes over extensive areas, also enabling evaluation of change over time. Empirical attribute estimation with remotely sensed data is frequently employed, yet with known limitations, especially over complex environments such as Mediterranean forests. In this study, the capacity of high spatial resolution (HSR imagery and related techniques to model structural parameters at the stand level (n = 490 in Mediterranean pines in Central Spain is tested using data from the commercial satellite QuickBird-2. Spectral and spatial information derived from multispectral and panchromatic imagery (2.4 m and 0.68 m sided pixels, respectively served to model structural parameters. Classification and Regression Tree Analysis (CART was selected for the modeling of attributes. Accurate models were produced of quadratic mean diameter (QMD (R2 = 0.8; RMSE = 0.13 m with an average error of 17% while basal area (BA models produced an average error of 22% (RMSE = 5.79 m2/ha. When the measured number of trees per unit area (N was categorized, as per frequent forest management practices, CART models correctly classified 70% of the stands, with all other stands classified in an adjacent class. The accuracy of the attributes estimated here is expected to be better when canopy cover is more open and attribute values are at the lower end of the range present, as related in the pattern of the residuals found in this study. Our findings indicate that attributes derived from

  17. Presence of large and medium-sized mammals in a burned pine forest in southwestern Turkey

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    Anil Soyumert

    2010-08-01

    Full Text Available Riassunto
    Presenza di grandi e medi mammiferi in pinete incendiate della Turchia sud-occidentale
    Nel periodo Novembre 2005-Agosto 2006, è stata verificata, tramite trappole fotografiche, la presenza di mammiferi di grandi e medie dimensioni in foreste di Pinus brutia integre e incendiate della Turchia sud-occidentale. Sono state ottenute fotografie di tre specie, cinghiale (Sus scrofa, volpe (Vulpes vulpes e faina (Martes foina. Le prime due sono state rinvenute in entrambe le aree, mentre la faina è stata accertata solo in boschi incendiati. I risultati del presente studio suggeriscono che gli stadi successionali intermedi successivi ai roghi possono essere ricolonizzati dalle comunità di mammiferi.

    doi:10.4404/hystrix-21.1-4488

  18. Nantucket Pine Tip Moth Control and Loblolly Pine Growth in Intensive Pine Culture: Two-Year Results

    Science.gov (United States)

    David L. Kulhavy; Jimmie L. Yeiser; L. Allen Smith

    2004-01-01

    Twenty-two treatments replicated four times were applied to planted loblolly pine, Pinus taeda L. on bedded industrial forest land in east Texas for measurement of growth impact of Nantucket pine tip moth (NPTM), Rhyacionia frustrana (Comstock), and effects on pine growth over 2 years. Treatments were combinations of Velpar, Oust, and Arsenal...

  19. EVALUATION OF 2+0 AGED NURSERY OF THE SCOTCH PINE (Pinus sylvestrisL. RAISED IN KASTAMONU-TASKOPRU FOREST NURSERY AS TO TSI QUALITY CLASSIFICATION

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    Nurcan DEMİRCİOĞLU

    2004-02-01

    Full Text Available In this study; 2+0 aged, bare root, Daday-Koldandere origin of Scotch pine seedlings, produced at Kastamonu–Taşköprü forest nursery, were used. First the morphological characters of the seedlings were determined and the appropriateness to TS 2265/February 1988 were examined. Furthermore, the sensitiveness of quality classification both TSI and newly formed for the mentioned scotch pine seedlings were checked with discriminate analysis. In the conclusion, the average values of the seedling height, the root collar diameter, seedling height / root collar diameter ratio, stem dry weight / root dry weight ratio, dry root percent, quality index of 2+0 aged scotch pine seedlings were determined as 11.62 cm, 2.93 mm, 40.14, 2.34, 30.65 %, 0.32 respectively. In addition, 92.7 % of the seedlings as to the seedling height criterion, 98.7 % of the seedlings as to the root collar diameter criterion, 91.4 % of the seedlings as to the seedling height - root collar diameter criterion, 92.7 % of the seedlings as to the stem dry weight / root dry weight ratio criterion were included in first quality class in respect of TSI quality classification.

  20. Seasonal measurements of organic acid fluxes over a ponderosa pine forest

    Science.gov (United States)

    Fulgham, S. R.; Brophy, P.; Link, M.; Ortega, J. V.; Farmer, D.

    2016-12-01

    The biosphere acts as both a source and a sink of oxidized organic compounds. Ignoring dry deposition leads to overestimation of secondary organic aerosols by aerosol models, while ignoring emission sources underestimates the budget of organic acids. Developing parameterizations for oxidized organic dry deposition and emission requires observational constraints. Although biosphere parameters are impacted by seasonal variability, most reactive, trace-gas exchange measurements are made for only short periods of time in the main growing season. Here we make fast (5 - 10 Hz) and sensitive (e.g. 0.73 ppt mean limit of detection for formic acid with 10 s averaging) eddy covariance measurements of gas-phase organic acids and other oxidized organic species with a high resolution Time-of-Flight Chemical Ionization Mass Spectrometer with acetate and iodide reagent ions. Measurements were made in 4 - 6 week campaigns over five seasons from summer 2015 to fall 2016 as part of the Seasonal Particles in Forests Flux studY (SPIFFY) at the Manitou Experimental Forest Observatory near Woodland Park, Colorado. Permeation tubes were used for online calibration of carboxylic acids including formic (C1), propionic (C3), butyric (C4), methacrylic (CH2C(CH3)COOH), valeric (C5), and heptanoic (C7) acids. Average daytime mixing ratios for formic acid were 100 ± 100 ppt in winter and 1500 ± 1000 ppt in summer 2016. Upward fluxes of formic acid were observed throughout the experiment, daytime averages and standard deviations ranging from 1900 ± 1000 ppt cm s-1 in winter to 170 ± 130 ppt cm s-1 in spring. Propionic (22 ± 22 ppt cm s-1), butyric (17 ± 16 ppt cm s-1), and methacrylic (3.5 ± 6.1 ppt cm s-1) acids exhibit a mix of upward, near-zero, and downward fluxes. Fluxes were exponentially correlated to temperature, suggesting an ecosystem-scale source of these acids. We also measure exchange velocities of a broad suite of other oxidized organic compounds (31.99 m/z to 311.523 m/z in

  1. Post-fire regeneration in a Mediterranean pine forest with historically low fire frequency

    Science.gov (United States)

    Buhk, Constanze; Götzenberger, Lars; Wesche, Karsten; Gómez, Pedro Sánchez; Hensen, Isabell

    2006-11-01

    Species of Mediterranean vegetation are known to regenerate directly after fire. The phenomenon of autosuccession (direct regeneration) has been found to be often combined with an increase of species richness during the first years after fire due to the high abundance of short-lived herbaceous plants facilitated by plentiful nutrients and light. The high degree of vegetation resilience, which is expressed in terms of autosuccession, has been explained by the selective pressure of fire in historic times. According to existing palaeoecological data, however, the Pinus halepensis forests in the Ricote Mountains (Province of Murcia, SE Spain) did not experience substantial fire impact before the presence of man nor are they especially fire-prone today. Therefore, we studied post-fire regeneration to find out if direct succession is present or if species from pre-fire vegetation are absent during the post-fire regeneration stages. Patterns of succession were deduced from observations made in sample plots on sites of a known regeneration age as well as in adjacent unburnt areas. The results of the vegetation analyses, including a Detrended Correspondence Analysis, indicate that Pinus halepensis forest regeneration after fire resembles autosuccession. As regards the presence of woody species, there is a high percentage similarity on north (83%) and south (70%) facing slopes during the first year after fire vs. reference areas which is due, for example, to direct regeneration of the resprouting Quercus coccifera or seeders like Pinus halepensis or Fumana laevipes. However, if herbaceous species are included in the comparison, the similarity on north-facing sites decreases (to 53%) with the presence of additional species, mainly ruderals like Anagallis arvensis or Reseda phyteuma, and even woody species on the burnt plots. This effect indicates "enhanced autosuccession", which was not found on south-facing sites where overall species richness was very high irrespective of

  2. Understory Plant Community Composition Is Associated with Fine-Scale Above- and Below-Ground Resource Heterogeneity in Mature Lodgepole Pine (Pinus contorta Forests.

    Directory of Open Access Journals (Sweden)

    Anne C S McIntosh

    Full Text Available Understory plant communities play critical ecological roles in forest ecosystems. Both above- and below-ground ecosystem properties and processes influence these communities but relatively little is known about such effects at fine (i.e., one to several meters within-stand scales, particularly for forests in which the canopy is dominated by a single species. An improved understanding of these effects is critical for understanding how understory biodiversity is regulated in such forests and for anticipating impacts of changing disturbance regimes. Our primary objective was to examine the patterns of fine-scale variation in understory plant communities and their relationships to above- and below-ground resource and environmental heterogeneity within mature lodgepole pine forests. We assessed composition and diversity of understory vegetation in relation to heterogeneity of both the above-ground (canopy tree density, canopy and tall shrub basal area and cover, downed wood biomass, litter cover and below-ground (soil nutrient availability, decomposition, forest floor thickness, pH, and phospholipid fatty acids (PLFAs and multiple carbon-source substrate-induced respiration (MSIR of the forest floor microbial community environment. There was notable variation in fine-scale plant community composition; cluster and indicator species analyses of the 24 most commonly occurring understory species distinguished four assemblages, one for which a pioneer forb species had the highest cover levels, and three others that were characterized by different bryophyte species having the highest cover. Constrained ordination (distance-based redundancy analysis showed that two above-ground (mean tree diameter, litter cover and eight below-ground (forest floor pH, plant available boron, microbial community composition and function as indicated by MSIR and PLFAs properties were associated with variation in understory plant community composition. These results provide

  3. Understory Plant Community Composition Is Associated with Fine-Scale Above- and Below-Ground Resource Heterogeneity in Mature Lodgepole Pine (Pinus contorta) Forests.

    Science.gov (United States)

    McIntosh, Anne C S; Macdonald, S Ellen; Quideau, Sylvie A

    2016-01-01

    Understory plant communities play critical ecological roles in forest ecosystems. Both above- and below-ground ecosystem properties and processes influence these communities but relatively little is known about such effects at fine (i.e., one to several meters within-stand) scales, particularly for forests in which the canopy is dominated by a single species. An improved understanding of these effects is critical for understanding how understory biodiversity is regulated in such forests and for anticipating impacts of changing disturbance regimes. Our primary objective was to examine the patterns of fine-scale variation in understory plant communities and their relationships to above- and below-ground resource and environmental heterogeneity within mature lodgepole pine forests. We assessed composition and diversity of understory vegetation in relation to heterogeneity of both the above-ground (canopy tree density, canopy and tall shrub basal area and cover, downed wood biomass, litter cover) and below-ground (soil nutrient availability, decomposition, forest floor thickness, pH, and phospholipid fatty acids (PLFAs) and multiple carbon-source substrate-induced respiration (MSIR) of the forest floor microbial community) environment. There was notable variation in fine-scale plant community composition; cluster and indicator species analyses of the 24 most commonly occurring understory species distinguished four assemblages, one for which a pioneer forb species had the highest cover levels, and three others that were characterized by different bryophyte species having the highest cover. Constrained ordination (distance-based redundancy analysis) showed that two above-ground (mean tree diameter, litter cover) and eight below-ground (forest floor pH, plant available boron, microbial community composition and function as indicated by MSIR and PLFAs) properties were associated with variation in understory plant community composition. These results provide novel insights

  4. Understory Plant Community Composition Is Associated with Fine-Scale Above- and Below-Ground Resource Heterogeneity in Mature Lodgepole Pine (Pinus contorta) Forests

    Science.gov (United States)

    McIntosh, Anne C. S.; Macdonald, S. Ellen; Quideau, Sylvie A.

    2016-01-01

    Understory plant communities play critical ecological roles in forest ecosystems. Both above- and below-ground ecosystem properties and processes influence these communities but relatively little is known about such effects at fine (i.e., one to several meters within-stand) scales, particularly for forests in which the canopy is dominated by a single species. An improved understanding of these effects is critical for understanding how understory biodiversity is regulated in such forests and for anticipating impacts of changing disturbance regimes. Our primary objective was to examine the patterns of fine-scale variation in understory plant communities and their relationships to above- and below-ground resource and environmental heterogeneity within mature lodgepole pine forests. We assessed composition and diversity of understory vegetation in relation to heterogeneity of both the above-ground (canopy tree density, canopy and tall shrub basal area and cover, downed wood biomass, litter cover) and below-ground (soil nutrient availability, decomposition, forest floor thickness, pH, and phospholipid fatty acids (PLFAs) and multiple carbon-source substrate-induced respiration (MSIR) of the forest floor microbial community) environment. There was notable variation in fine-scale plant community composition; cluster and indicator species analyses of the 24 most commonly occurring understory species distinguished four assemblages, one for which a pioneer forb species had the highest cover levels, and three others that were characterized by different bryophyte species having the highest cover. Constrained ordination (distance-based redundancy analysis) showed that two above-ground (mean tree diameter, litter cover) and eight below-ground (forest floor pH, plant available boron, microbial community composition and function as indicated by MSIR and PLFAs) properties were associated with variation in understory plant community composition. These results provide novel insights

  5. California State Waters Map Series—Offshore of Monterey, California

    Science.gov (United States)

    Johnson, Samuel Y.; Dartnell, Peter; Hartwell, Stephen R.; Cochrane, Guy R.; Golden, Nadine E.; Watt, Janet T.; Davenport, Clifton W.; Kvitek, Rikk G.; Erdey, Mercedes D.; Krigsman, Lisa M.; Sliter, Ray W.; Maier, Katherine L.; Johnson, Samuel Y.; Cochran, Susan A.

    2016-08-18

    IntroductionIn 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath bathymetry data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow subsurface geology.The Offshore of Monterey map area in central California is located on the Pacific Coast, about 120 km south of San Francisco. Incorporated cities in the map area include Seaside, Monterey, Marina, Pacific Grove, Carmel-by-the-Sea, and Sand City. The local economy receives significant resources from tourism, as well as from the Federal Government. Tourist attractions include the Monterey Bay Aquarium, Cannery Row, Fisherman’s Wharf, and the many golf courses near Pebble Beach, and the area serves as a gateway to the spectacular scenery and outdoor activities along the Big Sur coast to the south. Federal facilities include the Army’s Defense Language Institute, the Naval Postgraduate School, and the Fleet Numerical Meteorology and Oceanography Center (operated by the Navy). In 1994, Fort Ord army base, located between Seaside and Marina, was closed; much of former army base land now makes up the Fort Ord National Monument, managed by the U.S. Bureau of Land Management as part of the National Landscape Conservation System. In addition, part of the old Fort Ord is now occupied by California State University, Monterey Bay.The offshore part of the map area lies entirely within the Monterey Bay National

  6. Elevated CO{sub 2} in a prototype free-air CO{sub 2} enrichment facility affects photosynthetic nitrogen relations in a maturing pine forest

    Energy Technology Data Exchange (ETDEWEB)

    Ellsworth, D.S.; LaRoche, J.; Hendrey, G.R.

    1998-03-01

    A maturing loblolly pine (Pinus taeda L.) forest was exposed to elevated CO{sub 2} in the natural environment in a perturbation study conducted over three seasons using the free-air CO{sub 2} enrichment (FACE) technique. At the time measurements were begun in this study, the pine canopy was comprised entirely of foliage which had developed under elevated CO{sub 2} conditions (atmospheric CO{sub 2} {approx} 550 {micro}mol/mol{sup {minus}1}). Measurements of leaf photosynthetic responses to CO{sub 2} were taken to examine the effects of elevated CO{sub 2} on photosynthetic N nutrition in a pine canopy under elevated CO{sub 2}. Photosynthetic CO{sub 2} response curves (A-c{sub i} curves) were similar in FACE trees under elevated CO{sub 2} compared with counterpart trees in ambient plots for the first foliage cohort produced in the second season of CO{sub 2} exposure, with changes in curve form detected in the foliage cohorts subsequently produced under elevated CO{sub 2}. Differences in the functional relationship between carboxylation rate and N{sub a} suggest that for a given N{sub a} allocated among successive cohorts of foliage in the upper canopy, V{sub c max} was 17% lower in FACE versus Ambient trees. The authors also found that foliar Rubisco content per unit total protein derived from Western blot analysis was lower in late-season foliage in FACE foliage compared with ambient-grown foliage. The results illustrate a potentially important mode of physiological adjustment to growth conditions that may operate in forest canopies. Findings suggest that mature loblolly pine trees growing in the field may have the capacity for shifts in intrinsic nitrogen utilization for photosynthesis under elevated CO{sub 2} that are not dependent on changes in leaf N. Findings suggest a need for continued examination of internal feedbacks at the whole-tree and ecosystem level in forests that may influence long-term photosynthetic responses to elevated CO{sub 2}.

  7. ELEVATED CO{sub 2} IN A PROTOTYPE FREE-AIR CO{sub 2} ENRICHMENT FACILITY AFFECTS PHOTOSYNTHETIC NITROGEN RELATIONS IN A MATURING PINE FOREST

    Energy Technology Data Exchange (ETDEWEB)

    ELLSWORTH,D.S.; LA ROCHE,J.; HENDREY,G.R.

    1998-03-01

    A maturing loblolly pine (Pinus taeda L.) forest was exposed to elevated CO{sub 2} in the natural environment in a perturbation study conducted over three seasons using the free-air CO{sub 2} enrichment (FACE) technique. At the time measurements were begun in this study, the pine canopy was comprised entirely of foliage which had developed under elevated CO{sub 2} conditions (atmospheric [CO{sub 2}] {approx} 550 {micro}mol mol{sup {minus}1}). Measurements of leaf photosynthetic responses to CO{sub 2} were taken to examine the effects of elevated CO{sub 2} on photosynthetic N nutrition in a pine canopy under elevated CO{sub 2}. Photosynthetic CO{sub 2} response curves (A-c{sub i} curves) were similar in FACE trees under elevated CO{sub 2} compared with counterpart trees in ambient plots for the first foliage cohort produced in the second season of CO{sub 2} exposure, with changes in curve form detected in the foliage cohorts subsequently produced under elevated CO{sub 2}. Differences in the functional relationship between carboxylation rate and N{sub a} suggest that for a given N{sub a} allocated among successive cohorts of foliage in the upper canopy, V{sub c max} was 17% lower in FACE versus Ambient trees. The authors also found that foliar Rubisco content per unit total protein derived from Western blot analysis was lower in late-season foliage in FACE foliage compared with ambient-grown foliage. The results illustrate a potentially important mode of physiological adjustment to growth conditions that may operate in forest canopies. Their findings suggest that mature loblolly pine trees growing in the field may have the capacity for shifts in intrinsic nitrogen utilization for photosynthesis under elevated CO{sub 2} that are not dependent on changes in leaf N. While carboxylation efficiency per unit N apparently decreased under elevated CO{sub 2}, photosynthetic rates in trees at elevated CO{sub 2} concentrations {approx} 550 pmol mol{sub {minus}1} are still

  8. Long-term trends of changes in pine and oak foliar nitrogen metabolism in response to chronic nitrogen amendments at Harvard Forest, MA.

    Science.gov (United States)

    Minocha, Rakesh; Turlapati, Swathi A; Long, Stephanie; McDowell, William H; Minocha, Subhash C

    2015-08-01

    We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements were analyzed for control, low N (LN, 50 kg NH4NO3 ha(-1) year(-1)) and high N (HN, 150 kg NH4NO3 ha(-1) year(-1)) treatments. In the pine stands, partitioning of excess N into foliar PAs and AAs increased with both N treatments until 2002. By 2005, several of these effects on N metabolites disappeared for HN, and by 2008 they were mostly observed for LN plot. A significant decline in foliar Ca and P was observed mostly with HN for a few years until 2005. However, sapwood data actually showed an increase in Ca, Mg and Mn and no change in PAs in the HN plot for 2008, while AAs data revealed trends that were generally similar to foliage for 2008. Concomitant with these changes, mortality data revealed a large number of dead trees in HN pine plots by 2002; the mortality rate started to decline by 2005. Oak trees in the hardwood plot did not exhibit any major changes in PAs, AAs, nutrients and mortality rate with LN treatment, indicating that oak trees were able to tolerate the yearly doses of 50 kg NH4NO3 ha(-1) year(-1). However, HN trees suffered from physiological and nutritional stress along with increased mortality in 2008. In this case also, foliar data were supported by the sapwood data. Overall, both low and high N applications resulted in greater physiological stress to the pine trees than the oaks. In general, the time course of changes in metabolic data are in agreement with the published reports on changes in soil chemistry and microbial community structure, rates of soil carbon sequestration and production of woody biomass for this chronic N study. This correspondence of selected metabolites

  9. Common environmental factors explain both ectomycorrhizal species diversity and pine regeneration variability in a post-fire Mediterranean forest.

    Science.gov (United States)

    Buscardo, Erika; Freitas, Helena; Pereira, João Santos; De Angelis, Paolo

    2011-08-01

    Natural seedling regeneration and establishment after stand replacing wildfires is influenced by a series of environmental and biological constraints. In this study, we characterized the diversity and structure of the ectomycorrhizal (ECM) fungal community associated with post-fire naturally regenerated maritime pine saplings, and individuate the environmental factors responsible for fungal species distribution. We also identify the main environmental factors responsible for maritime pine regeneration variability and assessed the relation between saplings performance and ECM fungal diversity indices. Fungal species were identified by direct sequencing of internal transcribed spacer regions. Five years after the disturbance event, a total of 30 taxa colonized the pine saplings. The ECM fungal community was dominated by ruderal species of the genus Rhizopogon (present in almost half of the samples). Almost one third of the identified ECM fungal species belonged to the family Thelephoraceae. Typical k-selected species like Amanita pantherina, Boletus aestivalis, Lactarius chrysorrheus, and Russula densifolia were found on pine saplings collected in proximity of unburnt pine trees, in correspondence with low erosion extents. Pine regeneration varied throughout the study areas and was enhanced at higher elevations, in correspondence with moderate slopes, shallower soils, and a reduced cover of ericaceous shrubs and bare ground. These conditions were found in close proximity to patches of pine trees that survived the disturbance event and were previously characterized by a higher pre-fire pine biomass. Even though no correlations were found between saplings performance and ECM fungal diversity indices, common environmental factors (i.e., ericaceous shrub cover, extent of erosion, slope, and soil depth) were responsible for shaping the ECM fungal distribution and for describing most of the explained regeneration variability.

  10. Carbon balance of a partially harvested mixed conifer forest following mountain pine beetle attack and its comparison to a clear-cut

    Directory of Open Access Journals (Sweden)

    A. Mathys

    2013-08-01

    Full Text Available The recent mountain pine beetle (MPB outbreak has had an impact on the carbon (C cycling of lodgepole pine forests in British Columbia. This study examines how partial harvesting as a forest management response to MPB infestation affects the net ecosystem production (NEP of a mixed conifer forest (MPB-09 in Interior BC. MPB-09 is a 70-year-old stand that was partially harvested in 2009 after it had been attacked by MPB. Using the eddy-covariance technique, the C dynamics of the stand were studied over two years and compared to an adjacent clear-cut (MPB-09C over the summertime. The annual NEP at MPB-09 increased from −108 g C m−2 in 2010 to −57 g C m−2 in 2011. The increase of NEP was due to the associated increase in annual gross ecosystem photosynthesis (GEP from 812 g C m−2 in 2010 to 954 g C m−2 in 2011, exceeding the increase in annual respiration (Re from 920 g C m−2 to 1011 g C m−2 during the two years. During the four month period between June and September 2010, NEP at MPB-09C was −103 g C m−2, indicating high C losses in the clear-cut. MPB-09 was a C sink during the growing season of both years, increasing from 9 g C m−2 in 2010 to 47 g C m−2 in 2011. The increase of NEP in the partially harvested stand amounted to a recovery corresponding to a 26% increase in the maximum assimilation rate in the second year. This study shows that retaining the healthy residual forest can result in higher C sequestration of MPB-attacked stands compared to clear-cut harvesting.

  11. Evaluation of funnel traps for characterizing the bark beetle (Coleoptera: Scolytidae) communities in ponderosa pine forests of north-central Arizona.

    Science.gov (United States)

    Hayes, Christopher J; DeGomez, Tom E; Clancy, Karen M; Williams, Kelly K; McMillin, Joel D; Anhold, John A

    2008-08-01

    Lindgren funnel traps baited with aggregation pheromones are widely used to monitor and manage populations of economically important bark beetles (Coleoptera: Scolytidae). This study was designed to advance our understanding of how funnel trap catches assess bark beetle communities and relative abundance of individual species. In the second year (2005) of a 3-yr study of the bark beetle community structure in north-central Arizona pine (Pinus spp.) forests, we collected data on stand structure, site conditions, and local bark beetle-induced tree mortality at each trap site. We also collected samples of bark from infested (brood) trees near trap sites to identify and determine the population density of bark beetles that were attacking ponderosa pine, Pinus ponderosa Douglas ex Lawson, in the area surrounding the traps. Multiple regression models indicated that the number of Dendroctonus and Ips beetles captured in 2005 was inversely related to elevation of the trap site, and positively associated with the amount of ponderosa pine in the stand surrounding the site. Traps located closer to brood trees also captured more beetles. The relationship between trap catches and host tree mortality was weak and inconsistent in forest stands surrounding the funnel traps, suggesting that trap catches do not provide a good estimate of local beetle-induced tree mortality. However, pheromone-baited funnel trap data and data from gallery identification in bark samples produced statistically similar relative abundance profiles for the five species of bark beetles that we examined, indicating that funnel trap data provided a good assessment of species presence and relative abundance.

  12. State of pine decline in the southeastern United States

    Science.gov (United States)

    Lori Eckhardt; Mary Anne Sword Sayer; Don Imm

    2010-01-01

    Pine decline is an emerging forest health issue in the southeastern United States. Observations suggest pine decline is caused by environmental stress arising from competition, weather, insects and fungi, anthropogenic disturbances, and previous management. The problem is most severe for loblolly pine on sites that historically supported longleaf pine, are highly...

  13. The health of loblolly pine stands at Fort Benning, GA

    Science.gov (United States)

    Soung-Ryoul Ryu; G. Geoff Wang; Joan L. Walker

    2013-01-01

    Approximately two-thirds of the red-cockaded woodpecker (Picoides borealis) (RCW) groups at Fort Benning, GA, depend on loblolly pine (Pinus taeda) stands for nesting or foraging. However, loblolly pine stands are suspected to decline. Forest managers want to replace loblolly pine with longleaf pine (P. palustris...

  14. Biogeography and diversity of pines in the Madrean Archipelago

    Science.gov (United States)

    George M. Ferguson; Aaron D. Flesch; Thomas R. Van Devender

    2013-01-01

    Pines are important dominants in pine-oak, pine and mixed-conifer forests across the Colorado Plateau, southern Rocky Mountains, Sierra Madre Occidental, and in the intervening Sky Islands of the United States-Mexico borderlands. All 17 native species of pines in the Sky Islands region or their adjacent mountain mainlands reach the northern or southern margins of their...

  15. Tree Mortality following Prescribed Fire and a Storm Surge Event in Slash Pine (Pinus elliottii var. densa Forests in the Florida Keys, USA

    Directory of Open Access Journals (Sweden)

    Jay P. Sah

    2010-01-01

    Full Text Available In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on postfire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with understory type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated with tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pinelands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase.

  16. Tree mortality following prescribed fire and a storm surge event in Slash Pine (pinus elliottii var. densa) forests in the Florida Keys, USA

    Science.gov (United States)

    Sah, Jay P.; Ross, Michael S.; Snyder, James R.; Ogurcak, Danielle E.

    2010-01-01

    In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on postfire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with understory type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated with tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pinelands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase.

  17. The Results of the Project on Creation of Special Protection Zones in Pine Forests of the Altai Kray Based on Data from the Long-term Monitoring of Raptors’ Nesting Sites, Russia

    Directory of Open Access Journals (Sweden)

    Igor V. Karyakin

    2016-02-01

    Full Text Available This article provides the review of the condition of rare raptors’ species, nesting in strip-shaped pine forests of the Altai Kray. It also reflects negative trends for some species including the Golden Eagle (Aquila chrysaetos and the Eurasian Eagle Owl (Bubo Bubo due to constant felling. Criteria of selection of special protection zones of forests and zones of special protection in nature reserves in the pine forests of the Altai Kray were designed according to the results of the long-term monitoring of raptors. According to researches of 2015 zones of special protection were designed for Kamsalinsky, Mamontovsky and Kornilovsky nature reserves. Inspections conducted in all mentioned nature reserves and in Zavyalovsky nature reserve showed numerous violations of environmental legislation. Thereafter checks on compliance with the legislation in forest exploitation were initiated.

  18. Whitebark pine mortality related to white pine blister rust, mountain pine beetle outbreak, and water availability

    Science.gov (United States)

    Shanahan, Erin; Irvine, Kathryn M.; Thoma, David P.; Wilmoth, Siri K.; Ray, Andrew; Legg, Kristin; Shovic, Henry

    2016-01-01

    Whitebark pine (Pinus albicaulis) forests in the western United States have been adversely affected by an exotic pathogen (Cronartium ribicola, causal agent of white pine blister rust), insect outbreaks (Dendroctonus ponderosae, mountain pine beetle), and drought. We monitored individual trees from 2004 to 2013 and characterized stand-level biophysical conditions through a mountain pine beetle epidemic in the Greater Yellowstone Ecosystem. Specifically, we investigated associations between tree-level variables (duration and location of white pine blister rust infection, presence of mountain pine beetle, tree size, and potential interactions) with observations of individual whitebark pine tree mortality. Climate summaries indicated that cumulative growing degree days in years 2006–2008 likely contributed to a regionwide outbreak of mountain pine beetle prior to the observed peak in whitebark mortality in 2009. We show that larger whitebark pine trees were preferentially attacked and killed by mountain pine beetle and resulted in a regionwide shift to smaller size class trees. In addition, we found evidence that smaller size class trees with white pine blister rust infection experienced higher mortality than larger trees. This latter finding suggests that in the coming decades white pine blister rust may become the most probable cause of whitebark pine mortality. Our findings offered no evidence of an interactive effect of mountain pine beetle and white pine blister rust infection on whitebark pine mortality in the Greater Yellowstone Ecosystem. Interestingly, the probability of mortality was lower for larger trees attacked by mountain pine beetle in stands with higher evapotranspiration. Because evapotranspiration varies with climate and topoedaphic conditions across the region, we discuss the potential to use this improved understanding of biophysical influences on mortality to identify microrefugia that might contribute to successful whitebark pine conservation

  19. 78 FR 45964 - Notice of Intent To Repatriate Cultural Items: Monterey Museum of Art, Monterey, CA

    Science.gov (United States)

    2013-07-30

    ... projectile points, 38 pendants or beads, 3 fire-starters, 4 hand tools, 6 fishing weights, 37 carvings, 1... stone. In the 1978 Deed of Gift to the Monterey Museum of Art, Mr. Holman notes that the objects were...

  20. Impacts of extreme weather events and climate variability on carbon exchanges in an age-sequence of managed temperate pine forests from 2003 to 201

    Science.gov (United States)

    Arain, M. A.

    2017-12-01

    North American temperate forests are a critical component of the global carbon cycle and regional water resources. A large portion of these forests has traditionally been managed for timber production and other uses. The response of these forests, which are in different stages of development, to extreme weather events such as drought and heat stresses, climate variability and management regimes is not fully understood. In this study, eddy covariance flux measurements in an age sequence (77-, 42-, and 14-years old as of 2016) of white pine (Pinus strobus L.) plantation forests in southern Ontario, Canada are examined to determine the impact of heat and drought stresses and climate variability over a 14 year period (2003 to 2016). The mean annual net ecosystem productivity (NEP) values were 195 ± 87, 512 ±161 and 103 ± 103 g C m-2 year-1 in 77-, 42- and 14-year-old forests respectively, over the study period. The youngest forest became a net carbon sink in the fifth year of its growth. Air temperature was a dominant control on carbon fluxes and heat stress reduced photosynthesis much more as compared to ecosystem respiration in the growing season. A large decrease in annual NEP was observed during years experiencing heat waves. Drought stress had the strongest impact on the middle age forest which had the largest carbon sink and water demand. In contrast, young forest was more sensitive to heat stress, than drought. Severity of heat and drought stress impacts was highly dependent on the timing of these events. Simultaneous occurrence of heat and drought stress in the early growing season such as in 2012 and 2016 had a drastic negative impact on carbon balance in these forests due to plant-soil-atmosphere feedbacks. Future research should consider the timing of the extreme events, the stage of forest development and effects of extreme events on component fluxes. This research helps to assess the vulnerability of managed forests and their ecological and hydrological

  1. Optimization Forest Thinning Measures for Carbon Budget in a Mixed Pine-Oak Stand of the Qingling Mountains, China: A Case Study

    Directory of Open Access Journals (Sweden)

    Lin Hou

    2016-11-01

    Full Text Available Forest thinning is a silviculture treatment for sustainable forest management. It may promote growth of the remaining individuals by decreasing stand density, reducing competition, and increasing light and nutrient availability to increase carbon sequestration in the forest ecosystem. However, the action also increases carbon loss simultaneously by reducing carbon and other nutrient inputs as well as exacerbating soil CO2 efflux. To achieve a maximum forest carbon budget, the central composite design with two independent variables (thinning intensity and thinning residual removal rate was explored in a natural pine-oak mixed stand in the Qinling Mountains, China. The net primary productivity of living trees was estimated and soil CO2 efflux was stimulated by the Yasso07 model. Based on two years observation, the preliminary results indicated the following. Evidently chemical compounds of the litter of the tree species affected soil CO2 efflux stimulation. The thinning residual removal rate had a larger effect than thinning intensity on the net ecosystem productivity. When the selective thinning intensity and residual removal rate was 12.59% and 66.62% concurrently, the net ecosystem productivity reached its maximum 53.93 t·ha−1·year−1. The lower thinning intensity and higher thinning residual removal rated benefited the net ecosystem productivity.

  2. Risk Assessment for the Southern Pine Beetle

    Science.gov (United States)

    Andrew Birt

    2011-01-01

    The southern pine beetle (SPB) causes significant damage (tree mortality) to pine forests. Although this tree mortality has characteristic temporal and spatial patterns, the precise location and timing of damage is to some extent unpredictable. Consequently, although forest managers are able to identify stands that are predisposed to SPB damage, they are unable to...

  3. Diversity and abundance of communities of birds associated to forests semideciduos and pine encino of the National Park Viñales

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    Sael Hanoi Pérez Báez

    2016-06-01

    Full Text Available The present work was carried out in the months of February to April 2009 in the forest semideciduo of the path "Marvel of Viñales" and the formation pine-encino of the Valley Ancón of the National Park Viñales and it pursued as main objective to evaluate the diversity and abundance of the communities of birds and its association grade with both formations. The method of circular parcels of fixed radio was used in 30 points of counts separated to 150 m one of other and for the study of vegetation he/she took like base the methodology proposed by James and Shugart (1970 and Noon (1981 with adaptations, he/she took state fenológico of the vegetable species and they measured different variables of the formation boscosa. They were detected a total of 44 species of birds for the semidesiduo and 42 in Ancón. He/she was association between several species of birds and vegetables of the formations in study, appreciating you increment of S with the Relative Abundance and the decrease of the height of the vegetation with the vegetable density. The communities of birds of the formation of forest semideciduo of the path "Marvels of Viñales" and of the forest of pine encino of "Valley Ancón" presented similar figures of wealth, diversity and equitatividad but they sustained differences in composition and it structures. In both study formations numeric dominancias of Turdus plumbeus and Vireo altiloquus registered and the difference was given by the abundance of Teretistris fernandinae in "Marvels of Viñales" and Tiaris canorus in Valley Ancón. The relationship was demonstrated between ornitocenosis and fitocenosis and several species of birds they associated in more measure to rosy Clusea, Callophilum antillanun, Cuban Quercus, Matayba oppositifolia and Cordovan leathers.

  4. Controls of Net Ecosystem Exchange at an Old Field, a Pine Plantation, and a Hardwood Forest under Identical Climatic and Edaphic Conditions-Isotopic Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chanton, J. P.; Mortazavi, B.

    2004-11-04

    During the past year we have submitted two manuscripts. 1. Mortazavi, B., J. Chanton, J.L. Prater, A.C. Oishi, R. Oren and G. Katul. Temporal variability in 13C of respired CO2 in a pine and a hardwood forest subject to similar climatic conditions (in Press). Oecologia 2. Mortazavi, B. and J. P. Chanton. Use of Keeling plots for determining sources of dissolved organic carbon in nearshore and open ocean systems (Published in Limnology and Oceanography (2004) Vol 49 pages 102-108). 3. Mortazavi, B., J. L. Prater, and J. P. Chanton (2004). A field-based method for simultaneous measurements of the 18O and 13C of soil CO2 efflux. Biogeosciences Vol 1:1-16 Most recent products delivered: Mortazavi, B. and J. P. Chanton. Abiotic and biotic controls on the 13C of respired CO2 in the southeastern US forest mosaics and a new technique for measuring the of soil CO2 efflux. Joint Biosphere Stable Isotope Network (US) and Stable Isotopes in Biosphere Atmosphere Exchange (EU) 2004 Meeting, Interlaken, Switzerland, March 31-April 4, 2004. Mortazavi, B., J. Chanton, J.L. Prater, A.C. Oishi, R. Oren and G. Katul. Temporal variability in 13C of respired CO2 in a pine and a hardwood forest subject to similar climatic conditions. American Geophysical Union Fall Meeting, San Francisco, USA, December 8-12, 2003. Prater, J., Mortazavi, B. and J. P. Chanton. Measurement of discrimination against 13C during photosynthesis and quantification of the short-term variability of 13C over a diurnal cycle. American Geophysical Union Fall Meeting, San Francisco, USA, December 8-12, 2003.

  5. Effects of different thinning systems on the economic value of ecosystem services: A case-study in a black pine peri-urban forest in Central Italy

    Directory of Open Access Journals (Sweden)

    Alessandro Paletto

    2017-12-01

    Full Text Available Sustainable Forest Management (SFM should be able to produce an optimal level of bundle of Ecosystem Services (ES, thus ensuring more resilient forest ecosystems also creating benefits for local population and human well-being. Yet, choosing between alternative forest management practices is not straightforward as it necessarily involves ES trade-offs. Forest management decisions have to reconcile the socio-economic and ecological contributions of forest ecosystems by fostering a synergistic relation between multiple ES while lowering ES trade-offs. The aim of the study is to analyze different forest management practices (selective and traditional thinning in black pine peri-urban forest in Central Italy, by investigating their contribution in terms of provisioning (wood production, cultural (recreational benefits, regulating (climate change mitigation ES. For each management option was performed: (1 the biophysical assessment of selected ES by using primary data and calculating indicators for wood production with special regard to biomass for energy use (living trees and deadwood volume harvested, recreational benefits (tourists’ preferences for each forest management practice, climate change mitigation (carbon sequestration in above-ground and below-ground biomass, and (2 the economic valuation of wood production, recreational benefits and climate change mitigation ES using direct and indirect methods (environmental evaluation techniques. The results show that the effects of the selective thinning on ES is higher that the effects of the traditional thinning. The economic value of the three ES provided by traditional and selective thinning are respectively: bioenergy production 154.2 € ha-1 yr-1 and 223.3 € ha-1 yr-1; recreational benefits 193.2 € ha-1 yr-1 and 231.9 € ha-1 yr-1; carbon sequestration 29.0 € ha-1 yr-1and 36.2 € ha-1 yr-1. The integrated (biophysical and economic assessment of ES in addition to the trade

  6. Naturally Occurring Compound Can Protect Pines from the Southern Pine Beetle

    Science.gov (United States)

    B.L. Strom; R.A. Goyer; J.L. Hayes

    1995-01-01

    The southern pine beetle (SPB), Dendroctonus frontalis, is the most destructive insect pest of southern pine forests. This tiny insect, smaller than a grain of rice, is responsible for killing pine timber worth millions of dollars on a periodic basis in Louisiana.

  7. Tip moth control and loblolly pine growth in intensive pine culture: four year results

    Science.gov (United States)

    David L. Kulhavy; Jimmie L. Yeiser; L. Allen Smith

    2006-01-01

    Twenty-two treatments replicated four times were applied to planted loblolly pine, Pinus taeda L., on bedded industrial forest land in east Texas for measurement of growth impact of Nantucket pine tip moth (NPTM), Rhyacionia frustrana Comstock, and effects on pine growth over 2 years. Treatments were combinations of Velpar®,...

  8. Surface fire intensity influences simulated crown fire behavior in lodgepole pine forests with recent mountain pine beetle-caused tree mortality

    Science.gov (United States)

    Chad M. Hoffman; Penelope Morgan; William Mell; Russell Parsons; Eva Strand; Steve. Cook

    2013-01-01

    Recent bark beetle outbreaks have had a significant impact on forests throughout western North America and have generated concerns about interactions and feedbacks between beetle attacks and fire. However, research has been hindered by a lack of experimental studies and the use of fire behavior models incapable of accounting for the heterogeneous fuel complexes. We...

  9. 12 years of irrigation in a drought stressed pine forest speeds up carbon cycling and alters the soil biome but has negligible effects on soil organic matter storage

    Science.gov (United States)

    Hagedorn, Frank; Hartmann, Martin; Brunner, Ivano; Rigling, Andreas; Herzog, Claude; Schaub, Marcus; Frey, Beat

    2017-04-01

    Inneralpine valleys are experiencing repeated summer droughts, which have caused a die-back of pine forests since the 1990s. Drought limits the metabolic activity and hence C cycling in the plant and soil system. The net effects of drought on soil organic matter (SOM) storage is, however, ambiguous as drought affects both C inputs and outputs. Moreover, in the long-term, water limitation is also altering above- and belowground diversity due to species-dependent resistance and adaptation to drought. In our study, we explored how ten years of irrigation of a water-limited pine forest in the central European Alps altered above- and belowground diversity and C cycling in the plant and soil systems. The decadal long irrigation during summer time strongly increased ecosystem productivity with litter fall and fine root biomass being increased by +50 and +40%, respectively. At the same time, soil CO2 efflux was stimulated by 60%, indicating that the removal of water limitation enhanced both the inputs and outputs of C into soils. The accelerated C cycling was also mirrored by compositional shifts in the soil microbiome. 454-pyrosequencing of ribosomal marker genes indicated that irrigation promoted bacteria and fungi with more copiotrophic life style strategies, that are typical for nutrient-rich conditions associated with a higher decomposition. Determination of SOM pools revealed a C loss in the organic layer under irrigation (-900 gC m-2) but a C gain in the mineral soil (+970 gC m-2), resulting in a negligible net effect. The likely mechanisms for the altered vertical SOM distribution might be (1) an accelerated mineralization of litter in conjunction with higher C inputs from the rhizosphere and/or (2) an increased incorporation of litter in the mineral soil as suggested by a litter bag experiment showing a stimulated activity of the macrofauna with a 5-fold increase of the earthworm density. In summary, our long-term irrigation experiment revealed that the removal of

  10. Diseases of lodgepole pine

    Science.gov (United States)

    Frank G. Hawksworth

    1964-01-01

    Diseases are a major concern to forest managers throughout the lodgepole pine type. In many areas, diseases constitute the primary management problem. As might be expected for a tree that has a distribution from Baja California, Mexico to the Yukon and from the Pacific to the Dakotas, the diseases of chief concern vary in different parts of the tree's range. For...

  11. Measuring the Effects of Disturbance & Climate on the CO2 & Energy Exchange of Ponderosa Pine Forests in the Pacific Northwest: Integration of Eddy Flux, Plant and Soil Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Beverly E. Law; Larry Mahrt

    2007-01-05

    The goal is to quantify and understand the influence of climate and disturbance on ecosystem processes and thus net carbon uptake by forests. The objective is to combine tower and ground-based observations to quantify the effects of disturbance on processes controlling carbon storage and CO{sub 2} and energy exchange in varying climatic conditions. Specific objectives are: (1) Investigate the effects of logging and fire on carbon storage and carbon dioxide and energy exchange in chronosequences of ponderosa pine, using consistent methodology; (2) Determine key environmental factors controlling carbon storage and carbon dioxide and energy exchange in these forests through a combination of measurements and process modeling; and (3) Assess spatial variation of the concentrations and transport in complex terrain. The eddy covariance method is used for measurements of CO2, water vapor, and energy exchanges in a chronosequence of ponderosa pine forests (burned in 2002 wildfire, 10 year-old stand, 90 year-old mature stand). The mature stand has been an AmeriFlux site since 2000 (following previous flux sites in young and old stands initiated in 1996). In addition to the eddy covariance measurements, a large suite of biological processes and ecosystem properties are determined for the purpose of developing independent forest carbon budgets and NEP estimates; these include photosynthesis, stand respiration, soil CO{sub 2} fluxes, annual litterfall, foliar chemistry, and bole increment, and soil organic matter among other parameters. The measurements are being integrated and evaluated with two ecosystem models (BIOME-BGC and SPA). Such analyses are needed to assess regional terrestrial ecosystem carbon budgets. The results will contribute scientific understanding of carbon processes, and will provide comprehensive data sets for forest managers and those preparing national carbon inventories to use in assessments of carbon sequestration in relation to interannual climate

  12. Analisis Keuntungan Pengusahaan Hutan Pinus (Pinus Merkusii Jung Et De Vriese Di KPH Pekalongan Barat (The Pine (Pinus merkusii Jung et de Vriese Forest Plantation Rentability Analysis In KPH West Pekalongan

    Directory of Open Access Journals (Sweden)

    Wahyu Andayani

    2011-01-01

    Full Text Available Economical value of the pine wood and resin in the last ten years has contributed significant revenue to the KPH West Pekalongan. This research is aimed to discover the optimum rotation of the development of forest pine to gain the maximum yield for the producer. The method used in this study is the analysis of the Land Expectation Value (LEV by estimating the physical production function which developes the wood and resin at every plant rotation. The results of the analysis is that in the rotation of 20 years, the pine forest could produce maximum net yield/ net (profitability /rentability from the sales of wood and resin, by using the real interest rate of 9,75% annually as follow : (a In the third bonita is Rp. 1.546.945, 36/hectar/rotation and (b in the fourth bonita is Rp. 2.032.392,56/hectar/rotation. By shortening the rotation from 35 years to 20 years, it results in the increasing yield of the forest pine plantation in KPH West Pakalongan of 6,1 % to 8,6% more than the real yield gained by the producer at present.Key words: Rentability, rotation, bonita, resin, LEV

  13. Garlic mustard and its effects on soil microbial communities in a sandy pine forest in central Illinois

    Science.gov (United States)

    Alexander B. Faulkner; Brittany E. Pham; Truc-Quynh D. Nguyen; Kenneth E. Kitchell; Daniel S. O' Keefe; Kelly D. McConnaughay; Sherri J. Morris

    2014-01-01

    This study evaluated the impacts of garlic mustard (Alliaria petiolata), an invasive species, on soil microbial community dynamics in a pine plantation on sandy soils in central Illinois. In situ soil carbon dioxide efflux was significantly greater in invaded sites. Similarly, in vitro carbon mineralization was significantly greater for soils...

  14. Effect of Intensive Forest Management Practices on Wood Properties and Pulp Yield of Young, Fast Growing Southern Pine

    Science.gov (United States)

    Timothy D. Faust; Alexander Clark; Charles E. Courchene; Barry D. Shiver; Monique L. Belli

    1999-01-01

    The demand for southern pine fiber is increasing. However, the land resources to produce wood fiber are decreasing. The wood industry is now using intensive cultural treatments, such as competition control, fertilization, and short rotations, to increase fiber production. The impact of these intensive environmental treatments on increased growth is positive and...

  15. Spatial variability of surface fuels in treated and untreated ponderosa pine forests of the southern Rocky Mountains

    Science.gov (United States)

    Emma Vakili; Chad M. Hoffman; Robert E. Keane; Wade T. Tinkham; Yvette Dickinson

    2016-01-01

    There is growing consensus that spatial variability in fuel loading at scales down to 0.5 m may govern fire behaviour and effects. However, there remains a lack of understanding of how fuels vary through space in wildland settings. This study quantifies surface fuel loading and its spatial variability in ponderosa pine sites before and after fuels treatment in the...

  16. Assessing the risk caused by ground level ozone to European forest trees: A case study in pine, beech and oak across different climate regions

    International Nuclear Information System (INIS)

    Emberson, Lisa D.; Bueker, Patrick; Ashmore, Mike R.

    2007-01-01

    Two different indices have been proposed for estimation of the risk caused to forest trees across Europe by ground-level ozone, (i) the concentration based AOT40 index (Accumulated Over a Threshold of 40 ppb) and (ii) the recently developed flux based AFstY index (Accumulated stomatal Flux above a flux threshold Y). This paper compares the AOT40 and AFstY indices for three forest trees species at different locations in Europe. The AFstY index is estimated using the DO 3 SE (Deposition of Ozone and Stomatal Exchange) model parameterized for Scots pine (Pinus sylvestris), beech (Fagus sylvatica) and holm oak (Quercus ilex). The results show a large difference in the perceived O 3 risk when using AOT40 and AFstY indices both between species and regions. The AOT40 index shows a strong north-south gradient across Europe, whereas there is little difference between regions in the modelled values of AFstY. There are significant differences in modelled AFstY between species, which are predominantly determined by differences in the timing and length of the growing season, the periods during which soil moisture deficit limits stomatal conductance, and adaptation to soil moisture stress. This emphasizes the importance of defining species-specific flux response variables to obtain a more accurate quantification of O 3 risk. - A new flux-based model provides a revised assessment of risks of ozone impacts to European forests

  17. Beyond annual budgets: carbon flux at different temporal scales in fire-prone Siberian Scots pine forests

    International Nuclear Information System (INIS)

    Wirth, C.; Czimczik, C.I.; Schulze, E.D.

    2002-01-01

    Along four chronosequences of fire-prone Siberian Scots pine forests we compared net primary production (NPP) and two different mass-based estimates of net ecosystem productivity (NEP C and NEP S ). NEP C quantifies changes in carbon pools along the chronosequences, whereas NEP S estimates the short-term stand-level carbon balance in intervals between fires. The chronosequences differed in the mean return interval of surface fires (unburned or moderately burned, 40 yr; heavily burned, 25 yr) and site quality (lichen versus Vaccinium type). Of the Vaccinium type (higher site quality) only a moderately burned chronosequence was studied. NEP C was derived from the rate of changes of two major carbon pools along the chronosequence time axes: (1) decomposition of old coarse woody debris (CWD) left from the previous generation after stand-replacing fire, and (2) accumulation of new carbon in biomass, CWD and soil organic layer by the regenerating stand. Young stands of all chronosequences were losing carbon at rates of -4 to -19 mol C/m 2 /yr (-48 to -228 g C/m 2 /yr). Depending on initial CWD pools and site-specific accumulation rates the stands became net carbon sinks after 12 yr (Vaccinium type) to 24 yr (lichen type) following the stand-replacing fire and offset initial carbon losses after 27 and 70 yr, respectively. Highest NEP C was reached in the unburned chronosequence (10.8 mol C/m 2 /yr or 130 g C/m 2 /yr). Maximum NEP C in the burned chronosequences ranged from 1.8 to 5.1 mol C/m 2 /yr (22 to 61 g C/m 2 /yr) depending on site quality and fire regime. Around a stand age of 200 yr NEP C was 1.6 ± 0.6 mol C/m 2 /yr (19 ± 7 g C/m 2 /yr) across all chronosequences. NEP S represents the current stand-level carbon accumulation in intervals between recurring surface fires and can be viewed as a mass-based analogue of net ecosystem exchange measured with flux towers. It was estimated based on measurements of current woody NPP, modelled decomposition of measured CWD

  18. Whole-tree and forest floor removal from a loblolly pine plantation have no effect on forest floor CO2 efflux 10 years after harvest

    Science.gov (United States)

    John R. Butnor; Kurt H. Johnsen; Felipe G. Sanchez

    2006-01-01

    Intensive management of southern pine plantations has yielded multifold increases in productivity over the last half century. The process of harvesting merchantable material and preparing a site for planting can lead to a considerable loss of organic matter. Intensively managed stands may experience more frequent disturbance as rotations decrease in length, exposing...

  19. Rapid increase in log populations in drought-stressed mixed-conifer and ponderosa pine forests in northern Arizona

    Science.gov (United States)

    Joseph L. Ganey; Scott C. Vojta

    2012-01-01

    Down logs provide important ecosystem services in forests and affect surface fuel loads and fire behavior. Amounts and kinds of logs are influenced by factors such as forest type, disturbance regime, forest man-agement, and climate. To quantify potential short-term changes in log populations during a recent global- climate-change type drought, we sampled logs in mixed-...

  20. Using structural sustainability for forest health monitoring and triage: Case study of a mountain pine beetle (Dendroctonusponderosae)-impacted landscape

    Science.gov (United States)

    Jonathan A. Cale; Jennifer G. Klutsch; Nadir Erbilgin; Jose F. Negron; John D. Castello

    2016-01-01

    Heavy disturbance-induced mortality can negatively impact forest biota, functions, and services by drastically altering the forest structures that create stable environmental conditions. Disturbance impacts on forest structure can be assessed using structural sustainability - the degree of balance between living and dead portions of a tree population’s size-...

  1. Principles and practices for the restoration of ponderosa pine and dry mixed-conifer forests of the Colorado Front Range

    Science.gov (United States)

    Robert N. Addington; Gregory H. Aplet; Mike A. Battaglia; Jennifer S. Briggs; Peter M. Brown; Antony S. Cheng; Yvette Dickinson; Jonas A. Feinstein; Kristen A. Pelz; Claudia M. Regan; Jim Thinnes; Rick Truex; Paula J. Fornwalt; Benjamin Gannon; Chad W. Julian; Jeffrey L. Underhill; Brett Wolk

    2018-01-01

    Wildfires have become larger and more severe over the past several decades on Colorado’s Front Range, catalyzing greater investments in forest management intended to mitigate wildfire risks. The complex ecological, social, and political context of the Front Range, however, makes forest management challenging, especially where multiple management goals including forest...

  2. Long term changes in atmospheric N and S throughfall deposition and effects on soil solution chemistry in a Scots pine forest in the Netherlands.

    Science.gov (United States)

    Boxman, Andries W; Peters, Roy C J H; Roelofs, Jan G M

    2008-12-01

    In a Scots pine forest the throughfall deposition and the chemical composition of the soil solution was monitored since 1984. (Inter)national legislation measures led to a reduction of the deposition of nitrogen and sulphur. The deposition of sulphur has decreased by approximately 65%. The total mineral-nitrogen deposition has decreased by ca. 25%, which is mainly due to a reduction in ammonium-N deposition (-40%), since nitrate-N deposition has increased (+50%). The nitrogen concentration in the upper mineral soil solution at 10 cm depth has decreased, leading to an improved nutritional balance, which may result in improved tree vitality. In the drainage water at 90 cm depth the fluxes of NO3(-) and SO4(2-) have decreased, resulting in a reduced leeching of accompanying base cations, thus preserving nutrients in the ecosystem. It may take still several years, however, before this will meet the prerequisite of a sustainable ecosystem.

  3. Soil phosphorus fractionation as a tool for monitoring dust phosphorus signature underneath a Blue Pine (Pinus wallichiana canopy in a Temperate Forest

    Directory of Open Access Journals (Sweden)

    Mustafa-Nawaz Shafqat

    2016-12-01

    Full Text Available Aims of the study: This study aims (i to monitor the amount of dust deposition during dry season in the moist temperate forest; (ii to study nature of P fractions in the dust samples falling on the trees in the region; (iii to study soil P fractions as influenced by the processes of throughfall and stemflow of a Blue Pine (Pinus wallichiana canopy and to finger print the contribution of dust towards P input in the temperate forest ecosystem. Area of study: The site used for the collection of soil samples was situated at an elevation of 6900 feet above sea levels (temperate forest in Himalaya region in the Thandani area national forest located in the north west of Pakistan. Material and methods:  For soil sampling and processing, three forest sites with three old tree plants per site were selected at approximately leveled plain for surface soil sampling. Two dust samples were collected and analyzed for different physicochemical properties along with different P fractions. First dust sample was collected from a site situated at an elevation of 4000 feet and second one was collected from an elevation of 6500 feet above sea levels. Modified Hedley procedure for the fractionation of P in the dust and soil samples were used. Main results: The input of dust was 43 and 20 kg ha-1 during drier months of the year (September-June at lower and higher elevation sites respectively, and the dust from lower elevation site had relative more all P fractions than the other dust sample. However, HCl-Pi fraction was dominant in both samples. Both labile (water plus NaHCO3 and non-labile (NaOH plus HCl inorganic P (Pi fractions were significantly increased in the surface soil by both stemflow and throughfall compared to the open field soil. The buildup of NaOH and HCl-Pi pools in soils underneath the canopy might prove useful in fingerprinting the contribution of atmospheric dust towards P cycling in this temperate forest. Research highlights: The role of dust in

  4. Monterey Bay Aquarium Volunteer Guide Scheduling Analysis

    Science.gov (United States)

    2014-12-01

    TERMS 15. NUMBER OF Monterey Bay Aquarium, linear programing, network design, multi commodity flow, resilience PAGES 17. SECURITY 18. SECURITY...Volunteers fill many roles that include Aquarium guides, information desk attendants, divers, and animal caregivers . Julie Packard, Executive Director of...further analyze the resiliency of the shifts to changes in staffing levels caused by no-shows or drop-ins. 3 While the guide program managers have

  5. A perfect storm: multiple stressors interact to drive postfire regeneration failure of lodgepole pine and Douglas-fir forests in Yellowstone

    Science.gov (United States)

    Hansen, W. D.; Braziunas, K. H.; Rammer, W.; Seidl, R.; Turner, M. G.

    2017-12-01

    Twenty-first century forests will experience increased stress as environmental conditions and disturbance regimes change. Whether forests retain their structure or transitions to alternate states, particularly when affected by multiple stressors, remains unresolved. Subalpine forests in Yellowstone National Park, WY experience large severe wildfires, and postfire-tree regeneration is necessary to assure resilience. Drying is projected, causing frequent larger wildfires that could reduce seed supply and drought that could constrain postfire-seedling establishment. We asked what combinations of warming-drying conditions, increased fire frequency, and increased burned-patch size cause postfire tree-regeneration failure in Yellowstone? We conducted a simulation experiment to identify combinations of fire frequency, fire size, postfire climate, substrate type, and elevation where lodgepole-pine and Douglas-fir regeneration failed. We expected postfire densities to be reduced if burned-patch sizes exceeded effective dispersal distance, sequential fires burned before trees reached reproductive maturity, or drought occurred after fire. We also expected regeneration failure only where multiple stressors occurred simultaneously at low elevation or on poor substrates.Douglas-fir stands were most vulnerable to regeneration failure. 98% of simulated Douglas-fir stands located in the middle of large burned patches failed to regenerate 30 years post fire. Lodgepole-pine stands in the middle of large burned patches failed to regenerate if they were also located at low elevations (93%) or at higher elevations on soils with poor water retention (73%). Stands of serotinous lodgepole (i.e., trees with closed cones that open when heated) also failed to regenerate if fire recurred before trees were reproductively mature (82%). Drought constrained postfire regeneration, yet, enhanced establishment due to release from cold-temperatures during mid-to-late 21st century often outweighed

  6. Impact of a Mountain Pine Beetle Outbreak on Young Lodgepole Pine Stands in Central British Columbia

    OpenAIRE

    Dhar, Amalesh; Balliet, Nicole; Runzer, Kyle; Hawkins, Christopher

    2015-01-01

    The current mountain pine beetle (MPB) (Dendroctonous ponderosae Hopkins) epidemic has severely affected pine forests of Western Canada and killed millions of hectares of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forest. Generally, MPB attack larger and older (diameter > 20 cm or >60 years of age) trees, but the current epidemic extends this limit with attacks on even younger and smaller trees. The study’s aim was to investigate the extent of MPB attack in y...

  7. Silvicultural Considerations in Managing Southern Pine Stands in the Context of Southern Pine Beetle

    Science.gov (United States)

    James M. Guldin

    2011-01-01

    Roughly 30 percent of the 200 million acres of forest land in the South supports stands dominated by southern pines. These are among the most productive forests in the nation. Adapted to disturbance, southern pines are relatively easy to manage with even-aged methods such as clearcutting and planting, or the seed tree and shelterwood methods with natural regeneration....

  8. Mountain pine beetle-killed lodgepole pine for the production of submicron lignocellulose fibrils

    Science.gov (United States)

    Ingrid Hoeger; Rolland Gleisner; Jose Negron; Orlando J. Rojas; J. Y. Zhu

    2014-01-01

    The elevated levels of tree mortality attributed to mountain pine beetle (MPB) (Dendroctonus ponderosae Hopkins) in western North American forests create forest management challenges. This investigation introduces the production of submicron or nanometer lignocellulose fibrils for value-added materials from the widely available resource represented by dead pines after...

  9. White pine in the American West: A vanishing species - can we save it?

    Science.gov (United States)

    Leon F. Neuenschwander; James W. Byler; Alan E. Harvey; Geral I. McDonald; Denise S. Ortiz; Harold L. Osborne; Gerry C. Snyder; Arthur Zack

    1999-01-01

    Forest scientists ask that everyone, from the home gardener to the forest manager, help revive western white pine by planting it everywhere, even in nonforest environments such as our neighborhood streets, parks, and backyards. White pine, long ago considered the "King Pine," once dominated the moist inland forests of the Northwest, eventually spawning whole...

  10. Longleaf Pine: An Updated Bibliography

    Science.gov (United States)

    John S. Kush; Ralph S. Meldahl; William D. Boyer; Charles K. McMahon

    1996-01-01

    The longleaf pine (Pinus palustris Mill.) forest figured prominently in the cultural and economic development of the South. What was once one of the most extensive forest ecosystems in North America has now become critically endangered (6). At the time of European settlement, this ecosystem dominated as much as 92 million acres throughout the...

  11. Soil phosphorus fractionation as a tool for monitoring dust phosphorus signature underneath a Blue Pine (Pinus wallichiana) canopy in a Temperate Forest

    Energy Technology Data Exchange (ETDEWEB)

    Shafqat, M.N.; Shahid, S.; Eqani, S.A.M.A.S.; Shah, S.H.; Waseem, A.

    2016-07-01

    Aim of the study: This study aims (i) to monitor the amount of dust deposition during dry season in the moist temperate forest; (ii) to study nature of P fractions in the dust samples falling on the trees in the region; (iii) to study soil P fractions as influenced by the processes of throughfall and stemflow of a Blue Pine (Pinus wallichiana) canopy and to finger print the contribution of dust towards P input in the temperate forest ecosystem. Area of study: The site used for the collection of soil samples was situated at an elevation of 6900 feet above sea levels (temperate forest in Himalaya region) in the Thandani area national forest located in the north west of Pakistan. Material and methods: For soil sampling and processing, three forest sites with three old tree plants per site were selected at approximately leveled plain for surface soil sampling. Two dust samples were collected and analyzed for different physicochemical properties along with different P fractions. First dust sample was collected from a site situated at an elevation of 4000 feet and second one was collected from an elevation of 6500 feet above sea levels. Modified Hedley procedure for the fractionation of P in the dust and soil samples were used. Main results: The input of dust was 43 and 20 kg ha-1 during drier months of the year (September-June) at lower and higher elevation sites respectively, and the dust from lower elevation site had relative more all P fractions than the other dust sample. However, HCl-Pi fraction was dominant in both samples. Both labile (water plus NaHCO3) and non-labile (NaOH plus HCl) inorganic P (Pi) fractions were significantly increased in the surface soil by both stemflow and throughfall compared to the open field soil. The buildup of NaOH and HCl-Pi pools in soils underneath the canopy might prove useful in fingerprinting the contribution of atmospheric dust towards P cycling in this temperate forest. Research highlights: The role of dust in the cycling of P

  12. Resource Limitations Influence Growth and Vigor of Idaho Fescue, a Common Understory Species in Pacific Northwest Ponderosa Pine Forests

    Directory of Open Access Journals (Sweden)

    Craig A. Carr

    2016-12-01

    Full Text Available Alterations in under-canopy resource availability associated with elevated ponderosa pine (Pinus ponderosa Dougl. abundance can negatively influence understory vegetation. Experimental evidence linking under-canopy resource availability and understory vegetation is scarce. Yet this information would be beneficial in developing management strategies to recover desired understory species. We tested the effects of varying nitrogen (N and light availability on Idaho fescue (Festuca idahoensis Elmer, the dominant understory species in ponderosa pine/Idaho fescue plant associations in eastern Oregon. In a greenhouse experiment, two levels of N (50 kg∙N∙ha−1 and 0 kg∙N∙ha−1 and shade (80% shade and 0% shade were applied in a split-plot design to individual potted plants grown in soil collected from high abundance pine stands. Plants grown in unshaded conditions produced greater root (p = 0.0027 and shoot (p = 0.0017 biomass and higher cover values (p = 0.0378 compared to those in the shaded treatments. The addition of N had little effect on plant growth (p = 0.1602, 0.5129, and 0.0853 for shoot biomass, root biomass, and cover, respectively, suggesting that soils in high-density ponderosa pine stands that lack understory vegetation were not N deficient and Idaho fescue plants grown in these soils were not N limited. Management activities that increase under-canopy light availability will promote the conditions necessary for Idaho fescue recovery. However, successful restoration may be constrained by a lack of residual fescue or the invasion of more competitive understory vegetation.

  13. UNDERSTOREY OF PINE-PLANTATIONS ON DEGRADED SITES IN THE REGION OF DECIDUOUS FORESTS OF RIO GRANDE DO SUL

    Directory of Open Access Journals (Sweden)

    Franz H. Andrae

    2010-08-01

    Full Text Available In the central part of Rio Grande do Sul State understoreys of 12 stands of Pinus sp. and one of Araucaria angustifolia O.Ktze were studied, all growing on soils, degraded by agriculture. One pine stand, 10 years old, originated from a natural renovation, the others had been planted 25 to 30 years ago, Araucaria was seeded directly. A total of 575 plots were sampled, 25 m² each, distributed systematically within the stands. Measurements included pines overstorey, and all understorey woody species, separeted into layers of more than 1,3 m high and 1,3 to 0,3 m; the layer lower than 0,3 m included only natural renovation of pines. Understoreys were composed by 121 species, ocurring common and high value timber species, ornamental trees, native and exotic fruit tree species. A higher number of species was present with a very few individuals only. The presence of non woody species like grasses, herbs, ferns and lians also was quantified. The number of tree species and the presence of non woody species did not correlat with density of overstorey pines. Abundance and frequency of species showed no significant diferences, when samples were grouped according to their location in the center or close to stands edge. Distribution pattern of understorey trees within stands was quantified, using Cox’ index, species diversity was compared by means of Shannon-index. Similarity of stands was compared by Sörensen-Index. It was concluded, that exotic species planted on poor agricultural soil may not only be of farmers interest because of their high potential for wood production. These plantations also may be considered from conservationist point of view, since they show an unexpected high diversity, so contributing in a longer run to landscape improvement, possibly due to the small extension of stands.

  14. Predictions of fire behavior and resistance to control: for use with photo series for the ponderosa pine type, ponderosa pine and associated species type, and lodgepole pine type.

    Science.gov (United States)

    Franklin R. Ward; David V. Sandberg

    1981-01-01

    This publication presents tables on the behavior of fire and the resistance of fuels to control. The information is to be used with the publication, "Photo Series for Quantifying Forest Residues in the Ponderosa Pine Type, Ponderosa Pine and Associated Species Type, Lodgepole Pine Type" (Maxwell, Wayne G.; Ward, Franklin R. 1976. Gen. Tech. Rep. PNW-GTR-052....

  15. A dendrochronology based fire history of Jeffry pine-mixed conifer forests in the Sierra San Pedro Martir, Mexico

    Science.gov (United States)

    Scott L. Stephens; Carl N. Skinner; Samantha J. Gill

    2003-01-01

    Conifer forests in northwestern Mexico have not experienced systematic fire suppression or logging, making them unique in western North America. Fire regimes of Pinus jeffreyi Grev. & Balf. mixed conifer forests in the Sierra San Pedro Martir, Baja California, Mexico, were determined by identifying 105 fire dates from 1034 fire scars in 105 specimens. Fires were...

  16. Amphibian and reptile response to prescribed burning and thinning in pine-hardwood forests: pre-treatment results

    Science.gov (United States)

    William B. Sutton; Yong Wang; Callie J. Schweitzer

    2010-01-01

    Analysis of pretreatment data is essential to determine long-term effects of forest management on amphibians and reptiles. We present pre-treatment amphibian and reptile capture data from April 2005 to May 2006 for a long-term study on herpetofaunal response to prescribed burning and tree thinning in the William B. Bankhead National Forest, AL, United States....

  17. The response of epiphytes to anthropogenic disturbance of pine-oak forests in the highlands of Chiapas, Mexico

    NARCIS (Netherlands)

    Wolf, J.H.D.

    2005-01-01

    Epiphytes contribute up to over 30% of the vascular plant diversity of old-growth tropical rain forests, but little is known about their occurrence in exploited forests that are structurally altered. Here, I estimate epiphyte species richness and biomass on 35 oak host trees, equally divided over

  18. Lizard Microhabitat and Microclimate Relationships in Southeastern Pine-Hardwood Forests Managed With Prescribed Burning and Thinning

    Science.gov (United States)

    W.B. Sutton; Y. Wang; C.J. Schweitzer; D.A. Steen

    2014-01-01

    Understanding the impacts of disturbances in forest ecosystems is essential for long-term biodiversity conservation. Many studies have evaluated wildlife responses to various disturbances but most generally do not use changes in microclimate features or crohabitat structure to explain these responses. We examined lizard responses to two common forest management...

  19. Effects of tree size and spatial distribution on growth of ponderosa pine forests under alternative management scenarios

    Science.gov (United States)

    C.W. Woodall; C.E. Fiedler; R.E. McRoberts

    2009-01-01

    Forest ecosystems may be actively managed toward heterogeneous stand structures to provide both economic (e.g., wood production and carbon credits) and environmental benefits (e.g., invasive pest resistance). In order to facilitate wider adoption of possibly more sustainable forest stand structures, defining growth expectations among alternative management scenarios is...

  20. Utilization of the southern pines

    Energy Technology Data Exchange (ETDEWEB)

    Koch, P

    1972-01-01

    After several years out of print, this book is again available. The two-volume reference characterizes the southern pine tree as raw material and describes the process by which it is converted to use. All 10 species are considered. The book is addressed primarily to the incoming generation of researchers and industrial managers in the southern pine industry. Foremen, superintendents, quality control personnel, wood procurement men, forest managers, extension workers, professors, and students of wood technology should find the handbook of value.

  1. Resilience of Mediterranean terrestrial ecosystems and fire severity in semiarid areas: Responses of Aleppo pine forests in the short, mid and long term.

    Science.gov (United States)

    González-De Vega, S; De Las Heras, J; Moya, D

    2016-12-15

    In recent decades, the fire regime of the Mediterranean Basin has been disturbed by various factors: climate change; forest management policies; land cover; changed landscape. Size and severity have notably increased, which in turn have increased large fires events with >500ha burned (high severity). In spite of Mediterranean ecosystems' high resilience to fire, these changes have implied more vulnerability and reduced natural recovery with irreparable long-term negative effects. Knowledge of the response of ecosystems to increasing severity, mainly in semiarid areas, is still lacking, which is needed to rehabilitate and restore burned areas. Our approach assessed the resilience concept by focusing on the recovery of ecosystem functions and services, measured as changes in the composition and diversity of plant community vegetation and structure. This will be validated in the long term as a model of ecosystem response. Also, depending on the pre-fire characteristics of vegetation, fire severity and the post-fire management, this approach will lead to tools that can be applied to implement post-fire restoration efforts in order to help decision making in planning activities. Regarding Mediterranean ecosystems' ability to recover after wildfires, this study concludes that pre-fire communities are resilient in these fire-prone areas, but the window for natural recovery in semiarid areas of Aleppo pine forest in SE Iberian Peninsula varied from 3 to 15 post-fire years. Fire severity was also key for effects on the ecosystem: the vegetation types of areas burned with low and medium severity recovered naturally, while those areas with a high-severity burn induced shrublands. We concluded that very strong regeneration activity exists in the short term, and that the negative effects of medium- and high-severity fire are evidenced in the mid and long term, which affect natural recovery. Adaptive forest management to rehabilitate and restore burned Mediterranean ecosystems

  2. Foliar fungi of Scots pine (Pinus sylvestris)

    OpenAIRE

    Millberg, Hanna

    2015-01-01

    Scots pine (Pinus sylvestris) is an ecologically and economically important tree species in Fennoscandia. Scots pine needles host a variety of fungi, some with the potential to profoundly influence their host. These fungi can have beneficial or detrimental effects with important implications for both forest health and primary production. In this thesis, the foliar fungi of Scots pine needles were investigated with the aim of exploring spatial and temporal patterns, and development with needle...

  3. Growing season length as a key factor of cumulative net ecosystem exchange over the pine forest ecosystems in Europe

    Czech Academy of Sciences Publication Activity Database

    Danielewska, A.; Urbaniak, M.; Olejnik, Janusz

    2015-01-01

    Roč. 29, č. 2 (2015), s. 129-135 ISSN 0236-8722 Institutional support: RVO:67179843 Keywords : forest * carbon dioxide * eddy covariance * growing season length Subject RIV: EH - Ecology, Behaviour Impact factor: 1.067, year: 2015

  4. South Dakota's forests 2005

    Science.gov (United States)

    Ronald J. Piva; W. Keith Moser; Douglas D. Haugan; Gregory J. Josten; Gary J. Brand; Brett J. Butler; Susan J. Crocker; Mark H. Hansen; Dacia M. Meneguzzo; Charles H. Perry; Christopher W. Woodall

    2009-01-01

    The first completed annual inventory of South Dakota's forests reports almost 1.7 million acres of forest land. Softwood forests make up 74 percent of the total forest land area; the ponderosa pine forest type by itself accounts for 69 percent of the total.

  5. Forests

    Science.gov (United States)

    Louis R. Iverson; Mark W. Schwartz

    1994-01-01

    Originally diminished by development, forests are coming back: forest biomass is accumulating. Forests are repositories for many threatened species. Even with increased standing timber, however, biodiversity is threatened by increased forest fragmentation and by exotic species.

  6. Mountain pine beetle in lodgepole pine: mortality and fire implications (Project INT-F-07-03)

    Science.gov (United States)

    Jennifer G. Klutsch; Daniel R. West; Mike A Battaglia; Sheryl L. Costello; José F. Negrón; Charles C. Rhoades; John Popp; Rick Caissie

    2013-01-01

    Mountain pine beetle (Dendroctonus ponderosae Hopkins) has infested over 2 million acres of lodgepole pine (Pinus contorta Dougl. ex Loud.) forest since an outbreak began approximately in 2000 in north central Colorado. The tree mortality from mountain pine beetle outbreaks has the potential to alter stand composition and stand...

  7. The push–pull tactic for mitigation of mountain pine beetle (Coleoptera: Curculionidae) damage in lodgepole and whitebark pines

    Science.gov (United States)

    Nancy E. Gillette; Constance J. Mehmel; Sylvia R. Mori; Jeffrey N. Webster; David L. Wood; Nadir Erbilgin; Donald R. Owen

    2012-01-01

    In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (...

  8. Forest diversity and disturbance: changing influences and the future of Virginia's Forests

    Science.gov (United States)

    Christine J. Small; James L. Chamberlain

    2015-01-01

    The Virginia landscape supports a remarkable diversity of forests, from maritime dunes, swamp forests, and pine savannas of the Atlantic coastal plain, to post-agricultural pine-hardwood forests of the piedmont, to mixed oak, mixed-mesophytic, northern hardwood, and high elevation conifer forests in Appalachian mountain provinces. Virginia’s forests also have been...

  9. Bridging gaps: On the performance of airborne LiDAR to model wood mouse-habitat structure relationships in pine forests.

    Science.gov (United States)

    Jaime-González, Carlos; Acebes, Pablo; Mateos, Ana; Mezquida, Eduardo T

    2017-01-01

    LiDAR technology has firmly contributed to strengthen the knowledge of habitat structure-wildlife relationships, though there is an evident bias towards flying vertebrates. To bridge this gap, we investigated and compared the performance of LiDAR and field data to model habitat preferences of wood mouse (Apodemus sylvaticus) in a Mediterranean high mountain pine forest (Pinus sylvestris). We recorded nine field and 13 LiDAR variables that were summarized by means of Principal Component Analyses (PCA). We then analyzed wood mouse's habitat preferences using three different models based on: (i) field PCs predictors, (ii) LiDAR PCs predictors; and (iii) both set of predictors in a combined model, including a variance partitioning analysis. Elevation was also included as a predictor in the three models. Our results indicate that LiDAR derived variables were better predictors than field-based variables. The model combining both data sets slightly improved the predictive power of the model. Field derived variables indicated that wood mouse was positively influenced by the gradient of increasing shrub cover and negatively affected by elevation. Regarding LiDAR data, two LiDAR PCs, i.e. gradients in canopy openness and complexity in forest vertical structure positively influenced wood mouse, although elevation interacted negatively with the complexity in vertical structure, indicating wood mouse's preferences for plots with lower elevations but with complex forest vertical structure. The combined model was similar to the LiDAR-based model and included the gradient of shrub cover measured in the field. Variance partitioning showed that LiDAR-based variables, together with elevation, were the most important predictors and that part of the variation explained by shrub cover was shared. LiDAR derived variables were good surrogates of environmental characteristics explaining habitat preferences by the wood mouse. Our LiDAR metrics represented structural features of the forest

  10. Characterization of Maritime Pine Forests with Combination of Simulated P-Band SAR Data and Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    C. Albinet

    2012-01-01

    Full Text Available This paper describes a sensitivity study performed on simulated radar and optical remote sensing forest data. It presents how the dual model has been built up. The first step is a forest growth model fed with biophysical parameters. The geometrical description is then the input of an optical hyperspectral model, giving reflectance spectra, and a Synthetic Aperture Radar (SAR model, giving the polarimetric and interferometric observables. As an illustration, the first results obtained by both models outputs are presented, and fusions of these outputs are performed.

  11. The effects of H2SO4 and (NH42SO4 treatments on the chemistry of soil drainage water and pine seedlings in forest soil microcosms

    Directory of Open Access Journals (Sweden)

    M. I. Stutter

    2004-01-01

    Full Text Available An experiment comparing effects of sulphuric acid and reduced N deposition on soil water quality and on chemical and physical growth indicators for forest ecosystems is described. Six H2SO4 and (NH42SO4 treatment loads, from 0 – 44 and 0 – 25 kmolc ha-1 yr-1, respectively, were applied to outdoor microcosms of Pinus sylvestris seedlings in 3 acid to intermediate upland soils (calc-silicate, quartzite and granite for 2 years. Different soil types responded similarly to H2SO4 loads, resulting in decreased leachate pH, but differently to reduced N inputs. In microcosms of calc-silicate soil, nitrification of NH4 resulted in lower pH and higher cation leaching than in acid treatments. By contrast, in quartzite and granite soils, (NH42SO4 promoted direct cation leaching, although leachate pH increased. The results highlighted the importance of soil composition on the nature of the cations leached, the SO4 adsorption capacities and microbial N transformations. Greater seedling growth on calc-silicate soils under both treatment types was related to sustained nutrient availability. Reductions in foliar P and Mg with higher N treatments were observed for seedlings in the calc-silicate soil. There were few treatment effects on quartzite and granite microcosm tree seedlings since P limitation precluded seedling growth responses to treatments. Hence, any benefits of N deposition to seedlings on quartzite and granite soils appeared limited by availability of co-nutrients, exacerbated by rapid depletion of soil exchangeable base cations. Keywords: acidification, manipulation, nitrogen, ammonium, deposition, soil, drainage, pine, microcosms, forest

  12. Douglas-Fir Tussock Moth- and Douglas-Fir Beetle-Caused Mortality in a Ponderosa Pine/Douglas-Fir Forest in the Colorado Front Range, USA

    Directory of Open Access Journals (Sweden)

    José F. Negrón

    2014-12-01

    Full Text Available An outbreak of the Douglas-fir tussock moth, Orgyia pseudotsugata McDunnough, occurred in the South Platte River drainage on the Pike-San Isabel National Forest in the Colorado Front Range attacking Douglas-fir, Pseudotsuga menziesii (Mirb. Franco. Stocking levels, species composition, and tree size in heavily and lightly defoliated stands were similar. Douglas-fir tussock moth defoliation resulted in significant Douglas-fir mortality in the heavily defoliated stands, leading to a change in dominance to ponderosa pine, Pinus ponderosa Lawson. Douglas-fir beetle, Dendroctonus pseudotsuqae Hopkins, populations increased following the defoliation event but caused less mortality, and did not differ between heavily and lightly defoliated stands. Douglas-fir tussock moth-related mortality was greatest in trees less than 15 cm dbh (diameter at 1.4 m above the ground that grew in suppressed and intermediate canopy positions. Douglas-fir beetle-related mortality was greatest in trees larger than 15 cm dbh that grew in the dominant and co-dominant crown positions. Although both insects utilize Douglas-fir as its primary host, stand response to infestation is different. The extensive outbreak of the Douglas-fir tussock moth followed by Douglas-fir beetle activity may be associated with a legacy of increased host type growing in overstocked conditions as a result of fire exclusion.

  13. Impacts of silvicultural thinning treatments on beetle trap captures and tree attacks during low bark beetle populations in ponderosa pine forests of northern Arizona.

    Science.gov (United States)

    Gaylord, M L; Hofstetter, R W; Wagner, M R

    2010-10-01

    Our research used a combination of passive traps, funnel traps with lures, baited trees, and surveys of long-term thinning plots to assess the impacts of different levels of stand basal area (BA) on bark beetle tree attack and on trap captures of Ips spp., Dendroctonus spp., and their predators. The study occurred at two sites in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests, from 2004 to 2007 during low bark beetle populations. Residual stand BA ranged from 9.0 to 37.0 m2/ha. More predators and bark beetles were collected in passive traps in stands of lower BA than in stands of higher BA; however, significance varied by species and site, and total number of beetles collected was low. Height of the clear panel passive traps affected trap catches for some species at some sites and years. When pheromone lures were used with funnel traps [Ips pini (Say) lure: lanierone, +03/-97 ipsdienol], we found no significant difference in trap catches among basal area treatments for bark beetles and their predators. Similarly, when trees were baited (Dendroctonus brevicomis LeConte lure: myrcene, exo-brevicomin and frontalin), we found no significant difference for days to first bark beetle attack. Surveys of long-term thinning treatments found evidence of bark beetle attacks only in unthinned plots (approximately 37 m2/ha basal area). We discuss our results in terms of management implications for bark beetle trapping and control.

  14. Separating Trends in Whitebark Pine Radial Growth Related to Climate and Mountain Pine Beetle Outbreaks in the Northern Rocky Mountains, USA

    Directory of Open Access Journals (Sweden)

    Saskia L. van de Gevel

    2017-06-01

    Full Text Available Drought and mountain pine beetle (Dendroctonus ponderosae Hopkins outbreaks have affected millions of hectares of high-elevation conifer forests in the Northern Rocky Mountains during the past century. Little research has examined the distinction between mountain pine beetle outbreaks and climatic influence on radial growth in endangered whitebark pine (Pinus albicaulis Engelm. ecosystems. We used a new method to explore divergent periods in whitebark pine radial growth after mountain pine beetle outbreaks across six sites in western Montana. We examined a 100-year history of mountain pine beetle outbreaks and climate relationships in whitebark pine radial growth to distinguish whether monthly climate variables or mountain pine outbreaks were the dominant influence on whitebark pine growth during the 20th century. High mortality of whitebark pines was caused by the overlapping effects of previous and current mountain pine beetle outbreaks and white pine blister rust infection. Wet conditions from precipitation and snowpack melt in the previous summer, current spring, and current summer benefit whitebark pine radial growth during the following growing season. Whitebark pine radial growth and climate relationships were strongest in sites less affected by the mountain pine beetle outbreaks or anthropogenic disturbances. Whitebark pine population resiliency should continue to be monitored as more common periods of drought will make whitebark pines more susceptible to mountain pine beetle attack and to white pine blister rust infection.

  15. Amphibian and reptile responses to thinning and prescribed burning in mixed pine-hardwood forests of northwestern Alabama, USA

    Science.gov (United States)

    William B. Sutton; Yong Wang; Callie J. Schweitzer

    2013-01-01

    We evaluated the response of amphibians and reptiles to two levels of prescribed burning and three levels of thinning using a field experiment consisting of a before–after, control-impact, and factorial complete block design over a four year period in the William B. Bankhead National Forest located in northwestern Alabama. We captured 2643 individuals representing 47...

  16. A meteorological study of parks and timbered areas in the western yellow-pine forests of Arizona and New Mexico

    Science.gov (United States)

    G. A. Pearson

    1913-01-01

    The object of the study, the results of which are presented here, was to determine the influence of the forest cover upon climate locally in the Southwest, in so far as this influence might be of importance in the management of timberlands and the possible afforestation of parks and denuded areas. Since the bearing upon forestry rather than upon meteorology is the...

  17. Airborne laser scanner-assisted estimation of aboveground biomass change in a temperate oak-pine forest

    Science.gov (United States)

    Nicholas S. Skowronski; Kenneth L. Clark; Michael Gallagher; Richard A. Birdsey; John L. Hom

    2014-01-01

    We estimated aboveground tree biomass and change in aboveground tree biomass using repeated airborne laser scanner (ALS) acquisitions and temporally coincident ground observations of forest biomass, for a relatively undisturbed period (2004-2007; ∇07-04), a contrasting period of disturbance (2007-2009; ∇09-07...

  18. The effects of forest residual debris disposal on perennial grass emergence, growth, and survival in a ponderosa pine ecotone

    Science.gov (United States)

    Darin J. Law; Peter F. Kolb

    2007-01-01

    Soil surface conditions can have profound effects on plant seedling emergence and subsequent seedling survival. To test the hypothesis that different soil-surface treatments with logging residue affect range grass seedling emergence and survival, 6 alternative forest-residual treatments were established in the summer of 1998 following thinning of mature trees from...

  19. Response of lizards to high-severity wildfires in a southern United States mixed pine/hardwood forest

    Science.gov (United States)

    Adam ​Duarte; Donald J. Brown; Michael R. J. Forstner

    2017-01-01

    High-severity forest fires are increasing in large areas of the southern and western United States as the climate becomes warmer and drier. Natural resource managers need a better understanding of the short- and long-term effects of wildfires on lizard populations, but there is a paucity of studies focused on lizard-wildfire relationships. We used a before-after,...

  20. Determining the vulnerability of Mexican pine forests to bark beetles of the genus Dendroctonus Erichson (Coleoptera: Curculionidae: Scolytinae)

    Science.gov (United States)

    Y. Salinas-Moreno; A. Ager; C.F. Vargas; J.L. Hayes; G. Zuniga

    2010-01-01

    Bark beetles of the genus Dendroctonus are natural inhabitants of forests; under particular conditions some species of this genus can cause large-scale tree mortality. However, only in recent decades has priority been given to the comprehensive study of these insects in Mexico. Mexico possesses high ecological diversity in Dendroctonus-...

  1. Evaluation of the CONSUME and FOFEM fuel consumption models in pine and mixed hardwood forests of the eastern United States

    Science.gov (United States)

    Susan J. Prichard; Eva C. Karau; Roger D. Ottmar; Maureen C. Kennedy; James B. Cronan; Clinton S. Wright; Robert E. Keane

    2014-01-01

    Reliable predictions of fuel consumption are critical in the eastern United States (US), where prescribed burning is frequently applied to forests and air quality is of increasing concern. CONSUME and the First Order Fire Effects Model (FOFEM), predictive models developed to estimate fuel consumption and emissions from wildland fires, have not been systematically...

  2. Species and structural diversity affect growth of oak, but not pine, in uneven-aged mature forests

    NARCIS (Netherlands)

    Vanhellemont, Margot; Bijlsma, Rienk Jan; Keersmaeker, De Luc; Vandekerkhove, Kris; Verheyen, Kris

    2018-01-01

    The effects of mixing tree species on tree growth and stand production have been abundantly studied, mostly looking at tree species diversity effects while controlling for stand density and structure. Regarding the shift towards managing forests as complex adaptive systems, we also need insight into

  3. Litter-dwelling arthropod abundance peaks near coarse woody debris in loblolly pine forest of the southeastern United States.

    Science.gov (United States)

    Michael D. Ulyshen; J.L. Hanula

    2009-01-01

    Several recent studies have shown that many litter-dwelling arthropod and other invertebrate taxa (e.g., Isopoda, Chilopoda, Diplopoda, Araneae, Pseudo scorpionida, Coleoptera, and Gastropoda) are more numerous near dead wood than away from it in the broad-leaved forests of Europe (Jabin et al. 2004; Topp et al. 2006a, 2006b; Kappes et...

  4. Litter-dwelling arthropod abundance peaks near coarse woody debris in loblolly pine forests of the southeastern United States

    Science.gov (United States)

    Michael D. Ulyshen; James L. Hanula

    2009-01-01

    litter-dwelling arthropod and other invertebrate taxa (e.g., Isopoda, Chilopoda, Diplopoda, Araneae, Pseudoscorpionida, Coleoptera, and Gastropoda) are more numerous near dead wood than away from it in the broad-leaved forests of Europe(Jabin et al. 2004; Topp et al. 2006a, 2006b; Kappes et al. 2006; Kappes 2006; Jabin et al. 2007) and...

  5. CARBON AND NUTRIENT FLOW THROUGH MULTIPLE TROPHIC LEVELS IN A CO2-ENRICHED SOUTHERN PINE FOREST COMMUNITY - FINAL TECHNICAL REPORT

    Science.gov (United States)

    The ability to predict the consequences of global change is predicated on our understanding of controls of energy and material flows through ecosystems. Research was conducted at the Forest Atmosphere CO2 Transfer and Storage-1 (FACTS-1) site at Duke University. This is a flagship experiment of the ...

  6. Modelling the limits on the response of net carbon exchange to fertilization in a south-eastern pine forest

    Science.gov (United States)

    Chun-Tai. Lai; G. Katul; J. Butnor; M. Siqueira; D. Ellsworth; C. Maier; Kurt Johnsen; S. Mickeand; R. Oren

    2002-01-01

    Using a combination of model simulations and detailed measurements at a hierarchy of scales conducted at a sandhills forest site, the effect of fertilization on net ecosystem exchange (NEE) and its components in 6-year-old Pinus taeda stands was quantified. The detailed measurements, collected over a 20-d period in September and October, included gas...

  7. Spatial and temporal corroboration of a fire-scar-based fire history in a frequently burned ponderosa pine forest

    Science.gov (United States)

    Calvin A. Farris; Christopher H. Baisan; Donald A. Falk; Stephen R. Yool; Thomas W. Swetnam

    2010-01-01

    Fire scars are used widely to reconstruct historical fire regime parameters in forests around the world. Because fire scars provide incomplete records of past fire occurrence at discrete points in space, inferences must be made to reconstruct fire frequency and extent across landscapes using spatial networks of fire-scar samples. Assessing the relative accuracy of fire...

  8. Short-term belowground responses to thinning and burning treatments in southwestern ponderosa pine forests of the USA

    Science.gov (United States)

    Steven T. Overby; Stephen C. Hart

    2016-01-01

    Microbial-mediated decomposition and nutrient mineralization are major drivers of forest productivity. As landscape-scale fuel reduction treatments are being implemented throughout the fire-prone western United States of America, it is important to evaluate operationally how these wildfire mitigation treatments alter belowground processes. We quantified these important...

  9. Carbon transport in Monterey Submarine Canyon

    Science.gov (United States)

    Barry, J.; Paull, C. K.; Xu, J. P.; Clare, M. A.; Gales, J. A.; Buck, K. R.; Lovera, C.; Gwiazda, R.; Maier, K. L.; McGann, M.; Parsons, D. R.; Simmons, S.; Rosenberger, K. J.; Talling, P. J.

    2017-12-01

    Submarine canyons are important conduits for sediment transport from continental margins to the abyss, but the rate, volume, and time scales of material transport have been measured only rarely. Using moorings with current meters, sediment traps (10 m above bottom) and optical backscatter sensors, we measured near-bottom currents, suspended sediment concentrations, and sediment properties at 1300 m depth in Monterey Canyon and at a non-canyon location on the continental slope at the same depth. Flow and water column backscatter were used to characterize "ambient" conditions when tidal currents dominated the flow field, and occasional "sediment transport events" when anomalously high down-canyon flow with sediment-laden waters arrived at the canyon mooring. The ambient sediment flux measured in sediment traps in Monterey Canyon was 350 times greater than measured at the non-canyon location. Although the organic carbon content of the canyon sediment flux during ambient periods was low (1.8 %C) compared to the slope location (4.9 %C), the ambient carbon transport in the canyon was 130 times greater than at the non-canyon site. Material fluxes during sediment transport events were difficult to measure owing to clogging of sediment traps, but minimal estimates indicate that mass transport during events exceeds ambient sediment fluxes through the canyon by nearly 3 orders of magnitude, while carbon transport is 380 times greater. Estimates of the instantaneous and cumulative flux of sediment and carbon from currents, backscatter, and sediment properties indicated that: 1) net flux is down-canyon, 2) flux is dominated by sediment transport events, and 3) organic carbon flux through 1300 m in Monterey Canyon was ca. 1500 MT C per year. The injection of 1500 MTCy-1 into the deep-sea represents ca. 260 km2 of the sediment C flux measured at the continental slope station (5.8 gCm-2y-1) and is sufficient to support a benthic community carbon demand of 5 gCm-2y-1 over 300 km2.

  10. Effects of Different LiDAR Intensity Normalization Methods on Scotch Pine Forest Leaf Area Index Estimation

    Directory of Open Access Journals (Sweden)

    YOU Haotian

    2018-02-01

    Full Text Available The intensity data of airborne light detection and ranging (LiDAR are affected by many factors during the acquisition process. It is of great significance for the normalization and application of LiDAR intensity data to study the effective quantification and normalization of the effect from each factor. In this paper, the LiDAR data were normalized with range, angel of incidence, range and angle of incidence based on radar equation, respectively. Then two metrics, including canopy intensity sum and ratio of intensity, were extracted and used to estimate forest LAI, which was aimed at quantifying the effects of intensity normalization on forest LAI estimation. It was found that the range intensity normalization could improve the accuracy of forest LAI estimation. While the angle of incidence intensity normalization did not improve the accuracy and made the results worse. Although the range and incidence angle normalized intensity data could improve the accuracy, the improvement was less than the result of range intensity normalization. Meanwhile, the differences between the results of forest LAI estimation from raw intensity data and normalized intensity data were relatively big for canopy intensity sum metrics. However, the differences were relatively small for the ratio of intensity metrics. The results demonstrated that the effects of intensity normalization on forest LAI estimation were depended on the choice of affecting factor, and the influential level is closely related to the characteristics of metrics used. Therefore, the appropriate method of intensity normalization should be chosen according to the characteristics of metrics used in the future research, which could avoid the waste of cost and the reduction of estimation accuracy caused by the introduction of inappropriate affecting factors into intensity normalization.

  11. The Effect of Water Limitation on Volatile Emission, Tree Defense Response, and Brood Success of Dendroctonus ponderosae in Two Pine Hosts, Lodgepole, and Jack Pine

    OpenAIRE

    Lusebrink, Inka; Erbilgin, Nadir; Evenden, Maya L.

    2016-01-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae) has recently expanded its range from lodgepole pine forest into the lodgepole × jack pine hybrid zone in central Alberta, within which it has attacked pure jack pine. This study tested the effects of water limitation on tree defense response of mature lodgepole and jack pine (Pinus contorta and Pinus banksiana) trees in the field. Tree defense response was initiated by inoculation of trees with the MPB-associated fungus Grosmannia clavig...

  12. Transcriptome resources and functional characterization of monoterpene synthases for two host species of the mountain pine beetle, lodgepole pine (Pinus contorta) and jack pine (Pinus banksiana)

    Science.gov (United States)

    2013-01-01

    Background The mountain pine beetle (MPB, Dendroctonus ponderosae) epidemic has affected lodgepole pine (Pinus contorta) across an area of more than 18 million hectares of pine forests in western Canada, and is a threat to the boreal jack pine (Pinus banksiana) forest. Defence of pines against MPB and associated fungal pathogens, as well as other pests, involves oleoresin monoterpenes, which are biosynthesized by families of terpene synthases (TPSs). Volatile monoterpenes also serve as host recognition cues for MPB and as precursors for MPB pheromones. The genes responsible for terpene biosynthesis in jack pine and lodgepole pine were previously unknown. Results We report the generation and quality assessment of assembled transcriptome resources for lodgepole pine and jack pine using Sanger, Roche 454, and Illumina sequencing technologies. Assemblies revealed transcripts for approximately 20,000 - 30,000 genes from each species and assembly analyses led to the identification of candidate full-length prenyl transferase, TPS, and P450 genes of oleoresin biosynthesis. We cloned and functionally characterized, via expression of recombinant proteins in E. coli, nine different jack pine and eight different lodgepole pine mono-TPSs. The newly identified lodgepole pine and jack pine mono-TPSs include (+)-α-pinene synthases, (-)-α-pinene synthases, (-)-β-pinene synthases, (+)-3-carene synthases, and (-)-β-phellandrene synthases from each of the two species. Conclusion In the absence of genome sequences, transcriptome assemblies are important for defence gene discovery in lodgepole pine and jack pine, as demonstrated here for the terpenoid pathway genes. The product profiles of the functionally annotated mono-TPSs described here can account for the major monoterpene metabolites identified in lodgepole pine and jack pine. PMID:23679205

  13. Transcriptome resources and functional characterization of monoterpene synthases for two host species of the mountain pine beetle, lodgepole pine (Pinus contorta) and jack pine (Pinus banksiana).

    Science.gov (United States)

    Hall, Dawn E; Yuen, Macaire M S; Jancsik, Sharon; Quesada, Alfonso Lara; Dullat, Harpreet K; Li, Maria; Henderson, Hannah; Arango-Velez, Adriana; Liao, Nancy Y; Docking, Roderick T; Chan, Simon K; Cooke, Janice Ek; Breuil, Colette; Jones, Steven Jm; Keeling, Christopher I; Bohlmann, Jörg

    2013-05-16

    The mountain pine beetle (MPB, Dendroctonus ponderosae) epidemic has affected lodgepole pine (Pinus contorta) across an area of more than 18 million hectares of pine forests in western Canada, and is a threat to the boreal jack pine (Pinus banksiana) forest. Defence of pines against MPB and associated fungal pathogens, as well as other pests, involves oleoresin monoterpenes, which are biosynthesized by families of terpene synthases (TPSs). Volatile monoterpenes also serve as host recognition cues for MPB and as precursors for MPB pheromones. The genes responsible for terpene biosynthesis in jack pine and lodgepole pine were previously unknown. We report the generation and quality assessment of assembled transcriptome resources for lodgepole pine and jack pine using Sanger, Roche 454, and Illumina sequencing technologies. Assemblies revealed transcripts for approximately 20,000 - 30,000 genes from each species and assembly analyses led to the identification of candidate full-length prenyl transferase, TPS, and P450 genes of oleoresin biosynthesis. We cloned and functionally characterized, via expression of recombinant proteins in E. coli, nine different jack pine and eight different lodgepole pine mono-TPSs. The newly identified lodgepole pine and jack pine mono-TPSs include (+)-α-pinene synthases, (-)-α-pinene synthases, (-)-β-pinene synthases, (+)-3-carene synthases, and (-)-β-phellandrene synthases from each of the two species. In the absence of genome sequences, transcriptome assemblies are important for defence gene discovery in lodgepole pine and jack pine, as demonstrated here for the terpenoid pathway genes. The product profiles of the functionally annotated mono-TPSs described here can account for the major monoterpene metabolites identified in lodgepole pine and jack pine.

  14. Southern pine beetle in loblolly pine: simulating within stand interactions using the process model SPBLOBTHIN

    Science.gov (United States)

    Brian Strom; J. R. Meeker; J. Bishir; James Roberds; X. Wan

    2016-01-01

    Pine stand density is a key determinant of damage resulting from attacks by the southern pine beetle (SPB, Dendroctonus frontalis Zimm.). High-density stands of maturing loblolly pine (Pinus taeda L.) are at high risk for losses to SPB, and reducing stand density is the primary tool available to forest managers for preventing and mitigating damage. Field studies are...

  15. Maximizing peatland forest regeneration success at lowest cost to the atmosphere. Effects of soil preparation on Scots pine seedling vitality and GHG emissions

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, M.

    2013-06-01

    This dissertation investigated the impacts of soil preparation after clearcutting Scots pine (Pinus sylvestris L.) forest on thick-peated soil from silvicultural and climatic standpoints. Three growing seasons after outplanting, mounding most effectively secured seedling survival, growth, and vitality through improved soil aeration of the planting spot. However, other presumed benefits of mounding to seedlings such as warmer soil temperatures and faster organic matter decomposition were not confirmed here. Regeneration in scalps was unsuccessful due to waterlogged soil. Importantly when scalping, only the humus layer should be scraped off without creating depressions in the peat. Seedling tolerance to desiccated as well as waterlogged peat soil over one growing season was remarkable in controlled conditions. The impact of drought, however, was more immediate and severe as root and shoot growth, fractional colonization of ectomycorrhizal fungi, and root hydraulic conductance were reduced. Nevertheless, maintenance of rather high photochemical efficiency (expressed as variable to maximal chlorophyll fluorescence, Fv/Fm) especially in current-year needles despite harsh drought seemed to indicate a potential for seedling recovery. Polyamine analysis also revealed that new needles are preferred in protecting the different parts of the seedlings against drought stress. Wet-stressed seedlings, on the other hand, exhibited few signs of suffering. It was also demonstrated how the experimental environment a controlled versus field setting influences seedling tolerance to stress. The differing moisture levels within comparable microsites dry vs. wet scalps and ditch vs. inverted mounds had little influence on seedling growth and condition although physiological upset (i.e., Fv/Fm) was evident within scalps. Namely, the wetter the soil was, the lower Fv/Fm was. The fear of soil preparation accelerating GHG emissions, particularly CO{sub 2}, from peat into the atmosphere

  16. Fire-scar formation in Jeffrey pine - mixed conifer forests in the Sierra San Pedro Martir, Mexico

    Science.gov (United States)

    Scott L. Stephens; Danny L. Fry; Brandon M. Collins; Carl N. Skinner; Ernesto Franco-Vizcaino; Travis J. Freed

    2010-01-01

    Little is known about the probability of fire-scar formation. In this study, we examined all mixed conifer trees for fire-scar formation in a 16 ha watershed that burned as part of a 2003 wildfire in Sierra San Pedro Ma´rtir National Park (SSPM), Mexico. In addition, we examine the probability of fire-scar formation in relation to the previous fire interval in forests...

  17. Black carbon content in a ponderosa pine forest of eastern Oregon with varying seasons and intervals of prescribed burns

    Science.gov (United States)

    Matosziuk, L.; Hatten, J. A.

    2016-12-01

    Soil carbon represents a significant component of the global carbon cycle. While fire-based disturbance of forest ecosystems acts as a carbon source, the increased temperatures can initiate molecular changes to forest biomass that convert fast cycling organic carbon into more stable forms such as black carbon (BC), a product of incomplete combustion that contains highly-condensed aromatic structures and very low hydrogen and oxygen content. Such forms of carbon can remain in the soil for hundred to thousands of years, effectively creating a long-term carbon sink. The goal of this project is to understand how specific characteristics of prescribed burns, specifically the season of burn and the interval between burns, affect the formation, structure, and retention of these slowly degrading forms of carbon in the soil. Both O-horizon (forest floor) and mineral soil (0-15 cm cores) samples were collected from a season and interval of burn study in Malheur National Forest. The study area is divided into six replicate units, each of which is sub-divided into four treatment areas and a control. Beginning in 1997, each treatment area was subjected to: i) spring burns at five-year intervals, ii) fall burns at five-year intervals, iii) spring burns at 15-year intervals, or iv) fall burns at 15-year intervals. The bulk density, pH, and C/N content of each soil were measured to assess the effect of the burn treatments on the soil. Additionally, the amount and molecular structure of BC in each sample was quantified using the distribution of specific molecular markers (benzene polycarboxylic acids or BPCAs) that are present in the soil following acid digestion.

  18. Changes in transpiration and foliage growth in lodgepole pine trees following mountain pine beetle attack and mechanical girdling

    Science.gov (United States)

    Robert M. Hubbard; Charles C. Rhoades; Kelly Elder; Jose Negron

    2013-01-01

    The recent mountain pine beetle outbreak in North American lodgepole pine forests demonstrates the importance of insect related disturbances in changing forest structure and ecosystem processes. Phloem feeding by beetles disrupts transport of photosynthate from tree canopies and fungi introduced to the tree's vascular system by the bark beetles inhibit water...

  19. Southern Monterey Bay Littoral Cell CRSMP Critical Erosion Sites 2008

    Data.gov (United States)

    California Natural Resource Agency — PWA and Griggs (2004) defined three risk categories to Monterey Regional Water Pollution Control Agency (MRWPCA) facilities between Marina and Wharf II. These risk...

  20. Southern Monterey Bay Littoral Cell CRSMP Sensitive Habitat 2008

    Data.gov (United States)

    California Natural Resource Agency — One of the most important functions of the southern Monterey Bay coastal system is its role as a habitat for a unique flora and fauna. The beaches are habitat for...