Interactive effects of carbon dioxide concentration and light on the morphological and biomass characteristics of black spruce and white spruce seedlings

Botany ◽  
2009 ◽  
Vol 87 (1) ◽  
pp. 67-77 ◽  
Author(s):  
Jacob Marfo ◽  
Qing-Lai Dang

CO2–light interactions can influence the competition among boreal plants, but are poorly understood. We investigated the effect of such interactions on the growth and biomass of 1-year-old black spruce (Sb) ( Picea mariana (Mill.) BSP) and white spruce (Sw) ( Picea glauca (Moench) Voss) grown with CO2 concentrations ([CO2]) of 360 and 720 µmol·mol–1 under 30%, 50%, and 100% light, in greenhouses. There were significant two-way and three-way interactions. Root collar diameter (RCD) of Sw decreased with decreasing light, while in Sb, there was no significant difference in RCD for plants grown under 50% or 30% light. Height was greater for plants grown under 100% light than if the plants were shaded. Elevated [CO2] increased RCD by 33% and enhanced stem volume by 67%, 98%, and 84% under 100%, 50%, and 30% light, respectively. The CO2 enhancement of total biomass was relatively higher under lower light, and greater for Sb than Sw. Elevated [CO2] decreased specific leaf area under 50% light only. Root mass was generally higher under 100% light than when shaded. Elevated [CO2] increased the root mass of Sb under 100% light, but decreased it under 30% light. Elevated [CO2] decreased the shoot/root ratio under 100% light, but increased it under 30% light. Our data suggest that raising [CO2] will likely increase species competitiveness under low light conditions, and that the increase will be greater in species that are relatively shade tolerant.

2000 ◽  
Vol 76 (5) ◽  
pp. 775-782 ◽  
Author(s):  
G. Geoff Wang ◽  
J. Aurea Siemens ◽  
Vince Keenan ◽  
Daniel Philippot

Differences in survival and growth of black and white spruce seedlings planted on boreal mixedwood sites were tested for stock types (transplant versus container), site preparation (Donaren disc trenching versus no trenching), and plantation types (open versus sheltered) in southeastern Manitoba after eight or nine growing seasons. Mortality of open plantation (32.3%) and container stock (32.5%) were significantly higher than sheltered plantation (23.7%) and transplant stock (22.8%), respectively. Donaren trenching slightly reduced the mortality of black spruce but significantly increased the mortality of white spruce. Seedlings of container stock (110 cm) were significantly shorter than transplant stock (157 cm). Significant difference in height was found between open and sheltered plantations for black spruce but not for white spruce. Root collar diameter of container stock (15.6 mm) was significantly smaller than transplant stock (23.1 mm). Root collar diameter in sheltered plantations was significantly larger than that in open plantations for black spruce but not for white spruce. Black spruce open plantation had significantly smaller volume (97 cm3) compare to black spruce sheltered (210 cm3) and white spruce open (175 cm3) and sheltered (229 cm3) plantations. White spruce open plantations also had smaller volume than white spruce sheltered plantations. Container stock had smaller volume (89 cm3) than transplant stock (267 cm3). For transplant stock, strip plantations had a significantly higher volume (329 cm3) than open plantations (204 cm3). Based on above results, we recommend that (1) transplant stock should be used, (2) sheltered plantation site preparation should be used on boreal mixedwood sites, and (3) Donaren disc-trenching is not necessary for planting white spruce. Key words: silviculture, boreal mixedwood site, plantation


2000 ◽  
Vol 17 (2) ◽  
pp. 71-79 ◽  
Author(s):  
Sam K. Takyi ◽  
Graham R. Hillman

Abstract Artificial reforestation experiments compared survival and growth of five species of coniferous containerized seedlings, and seedling browsing by ungulates on a clearcut, drained, and mounded peatland in the boreal forest. Six to seven growing seasons after planting, 91% of all seedlings had survived. Height and diameter growth in five species were ranked as follows: Siberian latch (Larix sibirica Ledeb.) > lodgepole pine (Pinus contorta var. latifolia Engelm.) > tamarack (Larix laricina [Du Roi] K. Koch) > black spruce (Picea mariana [Mill.] B.S.P.) = white spruce(Picea glauca [Moench] Voss). Overall, tamarack height and diameter growth was twice that of either spruce species. Height and diameter growth of tamarack, black spruce, and white spruce planted in the spring was 65% to 97% greater than that of the more robust seedlings for the same species planted in the fall of the same year. Repeated winter browsing by ungulates did not affect survival and growth of the five species. In an experiment where survival and growth of tamarack and black spruce seedlings planted on the mounds were compared with that of seedlings planted on the flat areas between mounds, there were no differences in survival, height, or root collar diameter growth between the two planting sites. In the event that suitable peatlands are used to augment existing timber supplies, lowering the water table through ditching, combined with mound-planting, is a feasible method of reforesting timber-harvested, boreal wet sites with Siberian latch, lodgepole pine, and white spruce. Tamarack and black spruce, however, survive and grow well on drained peatlands without mound-planting. North. J. Appl. For. 17(2):71-79.


1994 ◽  
Vol 70 (2) ◽  
pp. 174-182 ◽  
Author(s):  
K. M. McClain ◽  
D. M. Morris ◽  
S. C. Hills ◽  
L. J. Buse

A spacing trial was established near Thunder Bay, Ontario in 1950. This trial consisted of black spruce (Picea mariana (Mill.) B.S.P.), white spruce (Picea glauca (Moench) Voss.), and red pine (Pinus resinosa Ait.) each established at three different spacings: 1.8 m, 2.7 m, and 3.6 m. This study examines the differences in growth and crown development as attributed to initial spacing, after 37 years. In addition, a benefit/cost analysis was performed to evaluate the economic efficiency of the various species/spacing combinations. Diameter at breast height, live crown length, and crown width, all exhibited significant (P < 0.001) increases as initial spacing increased, irrespective of species, but, height demonstrated a decreasing trend (P < 0.020). Gross total and merchantable stem volume per tree increased for all species as initial spacing increased; however, volume production per unit area decreased significantly for all species as spacing increased. The shift to higher-valued products from the wider-spaced plantations appeared to provide the best economic return. As a result of both greater merchantable volumes and greater percentages of these volumes available as a higher-valued product, benefit/cost ratios for red pine (0.995 to 1.337) were greater than those for the spruces (0.595 to 0.866). Although red pine currently represents less than 4% of Ontario's total regeneration effort, the results from this study suggest it deserves further consideration on some boreal sites. Key words: spacing trial, plantation growth, crown development, black spruce, white spruce, red pine, benefit/cost ratio


2017 ◽  
Vol 47 (8) ◽  
pp. 1116-1122 ◽  
Author(s):  
Rongzhou Man ◽  
Pengxin Lu ◽  
Qing-Lai Dang

Conifer winter damage results primarily from loss of cold hardiness during unseasonably warm days in late winter and early spring, and such damage may increase in frequency and severity under a warming climate. In this study, the dehardening dynamics of lodgepole pine (Pinus contorta Dougl. ex. Loud), jack pine (Pinus banksiana Lamb.), white spruce (Picea glauca (Moench) Voss), and black spruce (Picea mariana (Mill.) B.S.P.) were examined in relation to thermal accumulation during artificial dehardening in winter (December) and spring (March) using relative electrolyte leakage and visual assessment of pine needles and spruce shoots. Results indicated that all four species dehardened at a similar rate and to a similar extent, despite considerably different thermal accumulation requirements. Spring dehardening was comparatively faster, with black spruce slightly hardier than the other conifers at the late stage of spring dehardening. The difference, however, was relatively small and did not afford black spruce significant protection during seedling freezing tests prior to budbreak in late March and early May. The dehardening curves and models developed in this study may serve as a tool to predict cold hardiness by temperature and to understand the potential risks of conifer cold injury during warming–freezing events prior to budbreak.


2011 ◽  
Vol 28 (3) ◽  
pp. 146-151 ◽  
Author(s):  
Alain Paquette ◽  
Jean-Pierre Girard ◽  
Denis Walsh

Abstract Although studies in the past have reported that the deeper planting of conifers has no effect on seedling performance, most planting guidelines in use today still recommend that seedlings be planted to the rootcollar. Past studies were mostly observational, used bareroot seedlings, and often reported early results from just one or two depths of planting treatments. Most of the results available regarding planting depth for boreal species are anecdotal, although they are planted by the hundreds of millions every year. The present study reports no short-term (1 year) or long-term (15 to 19 years) negative effect of planting depth on the survival and height and diameter growth of black spruce, white spruce, and jack pine seedlings over three large, replicated experiments in the boreal forest of eastern and northern Quebec (eastern Canada). Four different depth treatments were compared, from manual planting at the rootcollar to the deepest mechanical planting treatment at 10 cm or more, making this the largest, longest-lasting study of its kind. Although, as expected, important differences in growth were present between species, all three commonly planted conifers reacted similarly to the planting depth treatments (no effect). This result can in part be attributed to an almost perfect control of frost heaving in the deepest two treatments. Planting depth effects were assessed using analysis of variance, multiple Tukey honestly significant difference, and uncorrected pairwise one-tailed t-tests to increase the probability of detecting a negative effect. Absolute differences and effect sizes (generally small and often positive with greater depths) were also analyzed.


1986 ◽  
Vol 62 (4) ◽  
pp. 226-232 ◽  
Author(s):  
R. F. Sutton

In mid-June 1978, hexazinone Gridball™ pellets were individually placed on the ground surface in two10-m × 10-m plots at each of two grid spacings in moderate-to-dense, woody weed growth in each of three boreal mixedwood stands in the Chapleau and Manitouwadge areas of Ontario. The rates of application were equivalent to 0.0, 1.4 and 4.2 kg a.i./ha. In these and a similar number of untreated plots, 16 white spruce (Picea glauca [Moench] Voss) were planted centrally in each plot at the same grid spacings used for the Gridballs™ but offset so as to give maximum separation between outplants and herbicide. The main study was supplemented by another to determine safe separation distance. GridballsTM at close spacing very significantly (P 0.01) increased growth of white spruce: at one location, the mean stem volume of spruce 7 years after planting was 438% that of spruce in the no-herbicide treatment; at a second location the comparable value was 503%. The evidence suggests that white spruce may be established in the boreal mixedwoods by underplanting and, concurrently, applying Gridballs™ at 1-m × 1-m spacing.


1969 ◽  
Vol 45 (3) ◽  
pp. 184-186 ◽  
Author(s):  
L. Heger

Sets of site-index curves were prepared from stem analyses of white spruce (Picea glauca (Moench) Voss) and black spruce (P. mariana (Mill.) BSP.) from various regions in the boreal forest of Canada. Ordinates of the site-index curves, computed for 5-year breast-height age intervals up to 75 years, and for 10-foot site-index intervals up to 70 feet, were compared within the species for the same values of site index and age. For breast-height ages below 55 years and for site index below 70 feet, the maximum absolute difference among the ordinates did not exceed 2.0 feet in white spruce, and 1.6 feet in black spruce; the corresponding average deviations were 0.75 and 0.80 feet. For breast-height ages above 55 years, these differences increased with age and, at 75 years, reached 8.8 feet in white spruce, and 3.8 feet in black spruce; the corresponding average deviations were 4.40 and 1.53 feet.


1983 ◽  
Vol 59 (4) ◽  
pp. 189-191 ◽  
Author(s):  
A. A. Alm

Black spruce (Picea mariana (Mill.) B.S.P.) and white spruce (Picea glauca (Moench) Voss) styrob-lock and paperpot and 3-0 and 2-2 seedlings were planted spring and fall. After four seasons of growth the container seedlings had survival and height growth as good or better than the nursery seedlings. There were no differences in performance between the two container systems. The 2-2 stock generally had better survival than the 3-0 stock. Survival of fall-planted stock was equal to or better than that of the spring-planted stock. Key words: white spruce, black spruce, styroplugs, paper pots, seedlings, transplants, artificial regeneration, fall vs spring planting


2010 ◽  
Vol 40 (8) ◽  
pp. 1576-1587 ◽  
Author(s):  
Ashley M. Thomson ◽  
Kevin A. Crowe ◽  
William H. Parker

Optimal breeding zones were developed for white spruce ( Picea glauca (Moench) Voss) in Ontario under present and future climate conditions to examine potential shifts due to climate change. These zones were developed by (i) determining a set of candidate breeding zones based on the relationship between measured performance variables and climate and (ii) employing a decision support model to select subsets of breeding zones that maximize geographic coverage subject to a constraint on the maximum number of zones. Current optimal breeding zones were based on 1961–1990 climate normals, and future breeding zones were based on three general circulation model (CGCM2, HADCM3, and CSIRO) predictions of 2041–2070 climate. Based on a maximum adaptive distance of 2.0 least significant difference values between sites within zones, 14 zones were required to cover the Ontario range of white spruce for the 1961–1990 data. Compared with breeding zones of other boreal conifers, current optimal breeding zones for white spruce were quite large, spanning up to 3° latitude and 10°–12° longitude and indicating large distances of effective seed transfer. Of the three general circulation models used to simulate future climate, HADCM3 B2 and CGCM2 B2 predicted 2041–2070 breeding zones that largely coincide with 1961–1990 zones. In contrast, CSIRO B2 indicated much narrower 2041–2070 breeding zones.


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