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You searched for: Journal name Canadian journal of forest research = Remove constraint Journal name: Canadian journal of forest research = Publication year rev 8003-1997 Remove constraint Publication year rev: 8003-1997 Source 1997 v.27 no.6 Remove constraint Source: 1997 v.27 no.6
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1. Classification of meteorological conditions to assess the potential for concrete frost formation in boreal forest floors

Author:
Proulx, S.; Stein, J.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 953-958
ISSN:
0045-5067
Subject:
meteorological data; boreal forests; spatial distribution; forest litter; air temperature; snow; frost; Quebec
Abstract:
... During spring 1990, 76% of the Lac Laflamme watershed (47 degrees N, 71 degrees W), Canada, was covered with substantial amounts of concrete frost in the boreal forest floors (litter, organic layer). Spatial distribution of concrete frost on the watershed was associated with forest floor composition. The objective of this note is to assess the potential for concrete frost formation in the forest f ...
DOI:
10.1139/x96-217

2. Crown conductance and tree and stand transpiration in a second-growth Abies amabilis forest

Author:
Martin, T.A.; Brown, K.J.; Cermak, J.; Ceulemans, R.; Kucera, J.; Meinzer, F.C.; Rombold, J.S.; Sprugel, D.G.; Hinckley, T.M.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 797-808
ISSN:
0045-5067
Subject:
mathematical models; solar radiation; diameter; water vapor; sap flow; height; Abies amabilis; leaf area; plant density; vapor pressure; Tsuga heterophylla; leaf conductance
Abstract:
... We measured whole-tree sap flow in a 43-year-old Abies amabilis (Dougl. ex Loud.) Dougl. ex J. Forbes - Tsuga heterophylla (Raf.) Sarg. forest in western Washington, U.S.A. We calculated whole-tree crown conductance to water vapor (gcrown) by substituting the sap flow data and meteorological measurements into the inverted Penman-Monteith equation. Individual tree sap flow and crown conductance var ...
DOI:
10.1139/x97-006

3. Importance of drainage ditches in emissions of methane from mires drained for forestry

Author:
Minkkinen, K.; Laine, J.; Nykanen, H.; Martikainen, P.J.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 949-952
ISSN:
0045-5067
Subject:
greenhouse effect; peatlands; methane; drainage channels; Finland
Abstract:
... Methane (CH4) fluxes from drainage ditches and adjoining strips between the ditches were measured in fall 1995 at a drained mire in Finland. The fluxes were measured at different mire sites using static chambers (diffusion and plant-mediated transport) and inverted funnels (ebullition). The emissions (chamber measurements) of CH4 from drainage ditch bottoms, ditch sides, and strips between ditches ...
DOI:
10.1139/x97-016

4. Oak regeneration and overstory density in the Missouri Ozarks

Author:
Larsen, D.R.; Metzger, M.A.; Johnson, P.S.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 869-875
ISSN:
0045-5067
Subject:
mathematical models; selection methods; canopy; Quercus; seedlings; plant characteristics; height; stand density; natural regeneration; stochastic processes; Missouri
Abstract:
... Reducing overstory density is a commonly recommended method of increasing the regeneration potential of oak (Quercus) forests. However, recommendations seldom specify the probable increase in density or the size of reproduction associated with a given residual overstory density. This paper presents logistic regression models that describe this relation for a forest in the Ozark Highlands of Missou ...
DOI:
10.1139/x97-010

5. Response of tree-line populations of foxtail pine (Pinus balfouriana) to climate variation over the last 1000 years

Author:
Lloyd, A.H.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 936-942
ISSN:
0045-5067
Subject:
history; growth rings; variance; stand density; snow; treeline; altitude; temperature; dendroclimatology; California
Abstract:
... Stand density, recruitment rate, and mortality rate in tree-line forests of foxtail pine (Pinus balfouriana Grev. &: Balf) were reconstructed for the last 1000 years. Mortality and recruitment were uncorrelated over the 1000-year period of the reconstruction. At the majority of sites, variance in recruitment was not significantly greater than variance in mortality. Recruitment and stand density we ...
DOI:
10.1139/x97-028

6. Somatic embryogenesis from tissues of mature sweetgum trees

Author:
Merkle, S.A.; Bailey, R.L.; Pauley, B.A.; Neu, K.A.; Kim, M.K.; Rugh, C.L.; Montello, P.M.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 959-964
ISSN:
0045-5067
Subject:
Liquidambar styraciflua; somatic embryogenesis; inflorescences; cell differentiation; stamens; 2,4-D; embryo (plant); benzyladenine; tissue culture
Abstract:
... Clonal propagation of superior genotypes of commercially important forest trees via somatic embryogenesis has been hindered by a general inability to initiate embryogenic cultures from tissues of mature trees. We tested staminate inflorescences of sweetgum (Liquidambar styraciflua L.) as a source of cells that might be redetermined from their differentiated state to an embryogenic state. Buds cont ...
DOI:
10.1139/x96-216

7. Structure and asymmetry of tree crowns in relation to local competition in a natural mature Scots pine forest

Author:
Rouvinen, S.; Kuuluvainen, T.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 890-902
ISSN:
0045-5067
Subject:
height; plant characteristics; Pinus sylvestris; plant competition; spatial distribution; stand density; mathematical models; solar radiation; diameter; width; Finland
Abstract:
... This study examined the effect of local competition, as determined by the number, size, and spatial distribution of neighboring trees, on crown base height, crown width, and crown asymmetry of trees growing in a natural mature Scots pine (Pinus sylvestris L.) forest in eastern Finland. Local competition was described with competition indices. Crown asymmetry was characterized as the distance and d ...
DOI:
10.1139/x97-012

8. Conservation of exchangeable cations after clear-cutting of a northern hardwood forest

Author:
Johnson, C.E.; Romanowicz, R.B.; Siccama, T.G.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 859-868
ISSN:
0045-5067
Subject:
logging; cation exchange capacity; calcium; soil organic matter; leaching; magnesium; soil horizons; forest management; fires; potassium; soil fertility; aluminum; hydrogen; drainage; biomass; biogeochemical cycles; clearcutting; New Hampshire
Abstract:
... Clear-cut logging of northern hardwoods disrupts forest nutrient cycling, often enhancing export of mineral nutrients (Ca, Mg, K) in drainage waters. When these leaching losses are added to mineral nutrient export in harvested wood, the total can be a significant fraction of the standing stocks of some ecosystems. Thus, changes in soil chemical properties after logging are important in determining ...
DOI:
10.1139/x96-192

9. Gene transfer by particle bombardment to Norway spruce and Scots pine pollen

Author:
Haggman, H.M.; Aronen, T.S.; Nikkanen, T.O.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 928-935
ISSN:
0045-5067
Subject:
Pinus sylvestris; Picea abies; transgenic plants; pollen; beta-glucuronidase; gene expression; Helianthus annuus; biolistics; pollination; genetic transformation; promoter regions
Abstract:
... The aim of the present work was to genetically transform Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) pollen in order to study the possibilities of obtaining transgenic progenies. The effects of different pollen origins and regulatory sequences on the beta-glucuronidase (GUS) expression in pollen were significant. The highest GUS expression in pine (55 +/- 7.7% of g ...
DOI:
10.1139/x97-024

10. Nutrient status of Amazonian caatinga forests in a seasonally dry area: nutrient fluxes in litter fall and analyses of soils

Author:
Coomes, D.A.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 831-839
ISSN:
0045-5067
Subject:
height; plant characteristics; rain; ecosystems; drainage; nitrogen; biogeochemical cycles; calcium; phosphorus; magnesium; potassium; soil fertility; rain forests; soil profiles; leaves; wood; biomass; seasonal variation; bulk density; plant litter; flooded conditions; Venezuela
Abstract:
... Amazonian caatinga, a low-stature forest type confined to seasonally waterlogged white-sand soils, occurs at La Esmeralda (Orinoco basin) under a lower rainfall than at San Carlos (Rio Negro basin), where many previous studies have been made. The nutrient status of forest types at La Esmeralda are compared and related to those of forests at San Carlos. At La Esmeralda, stature declines from well-d ...
DOI:
10.1139/x97-008

11. Sequence analysis and ozone-induced accumulation of polyubiquitin mRNA in Pinus sylvestris

Author:
Wegener, A.; Gimbel, W.; Werner, T.; Hani, J.; Ernst, D.; Sandermann, H. Jr.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 945-948
ISSN:
0045-5067
Subject:
Pinus sylvestris; ozone; gene expression; defense mechanisms; DNA libraries; messenger RNA; ubiquitin; nucleotide sequences; complementary DNA; amino acid sequences
Abstract:
... Plants are known to respond to ozone at the molecular level by the expression of defense-related genes. A cDNA library from Scots pine (Pinus sylvestris L.) was differentially screened, using labeled reverse-transcribed poly(A)+ RNA, isolated from ozone-treated Scots pine seedlings or nontreated seedlings. The longest ozone-induced clone (O3I-2.3) was further characterized by DNA sequencing and No ...
DOI:
10.1139/x97-023

12. Transgenic Populus: in vitro screening for resistance to cottonwood leaf beetle (Coleoptera: Chrysomelidae)

Author:
Kang, H.; Hall, R.B.; Heuchelin, S.A.; McNabb, H.S. Jr.; Mize, C.W.; Hart, E.R.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 943-944
ISSN:
0045-5067
Subject:
weight; transgenic plants; Chrysomela scripta; larvae; Populus canadensis; pest resistance; leaves
Abstract:
... Resistance of a nontransgenic Populus x euramericana clone, 'Ogy', and three transgenic 'Ogy' lines to the cottonwood leaf beetle, Chrysomela scripta F. was evaluated by in vitro feeding on tissue-culture plantlets. Resistance of the transgenic lines was investigated in terms of effects on leaf area consumed and insect larval weight. Leaf area consumed and insect weight were different between tran ...
DOI:
10.1139/x97-027

13. A stand-level model of carbon allocation and growth, calibrated for loblolly pine

Author:
Valentine, H.T.; Gregoire, T.G.; Burkhart, H.E.; Hollinger, D.Y.
Source:
Canadian journal of forest research = 1997 v.27 no.6 pp. 817-830
ISSN:
0045-5067
Subject:
height; plant characteristics; Pinus taeda; stand characteristics; mathematical models; carbon; dry matter accumulation; leaves; roots; wood; stems; calibration; plant density; biochemical pathways; photosynthates
Abstract:
... A stand-level model of carbon allocation and growth (Pipestem) is formulated as a set of differential equations that contain explicit parametrizations of annual rates of (i) production of photosynthate, (ii) dry-matter production, constructive respiration, and maintenance respiration of foliage, feeder roots, and live wood, (iii) foliage and feeder-root turnover, and (iv) loss of woody tissue to c ...
DOI:
10.1139/x97-033