Effect of gap size on litter decomposition and soil nitrate concentrations in a high-elevation spruce–fir forest

2003 ◽  
Vol 33 (11) ◽  
pp. 2210-2220 ◽  
Author(s):  
Cindy E Prescott ◽  
Graeme D Hope ◽  
Leandra L Blevins
Keyword(s):  
Forest Floor ◽  
Mineral Soil ◽  
High Elevation ◽  
N Availability ◽  
Abies Lasiocarpa ◽  
Subalpine Fir ◽  
Engelmann Spruce ◽  
Nitrate Losses ◽  
Nitrate Concentrations ◽  
High Elevation Forest

Possible mitigation of nitrate losses associated with clearcuts through harvesting smaller gaps was tested in a high-elevation forest of Engelmann spruce (Picea engelmannii Parry ex Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.). We measured concentrations of ammonium and nitrate after 6-week buried bag incubations of forest floor and mineral soil samples in replicated plots of uncut forest and gaps of 10, 1.0, and 0.1 ha and single-tree removal for 7 years after harvest. Nitrate concentrations in forest floor and mineral soil were elevated 3–7 years after harvesting in gaps of 0.1 ha and larger. Removal of the same proportion of trees as single trees did not result in increased nitrate concentrations, suggesting that nitrate losses could be reduced by harvesting single trees rather than creating gaps. Greater N availability was not associated with faster rates of decomposition of litter and forest floor, which were similar in gaps of all sizes (0–10 ha). Reciprocal transplant of forest floor and soil from the 10-ha gaps and the uncut forests indicated that changes in the nature of the forest floor or soil following harvest had a greater influence on nitrate concentrations than the changes in environmental conditions in the gaps.

Pathology of conifer seed and timing of germination in high-elevation subalpine fir and Engelmann spruce forests of the southern interior of British Columbia

1999 ◽  
Vol 29 (2) ◽  
pp. 187-193 ◽  
Author(s):  
Jianwen Zhong ◽  
Bart J van der Kamp
Keyword(s):  
British Columbia ◽  
Forest Floor ◽  
Mineral Soil ◽  
Seed Viability ◽  
Low Frequency ◽  
High Elevation ◽  
Subalpine Fir ◽  
Engelmann Spruce ◽  
Black Mold ◽  
Nurse Logs

Unstratified seed of Engelmann spruce (Picea engelmannii Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) in nylon mesh bags was placed on various natural and disturbed forest floor seed beds in the Engelmann Spruce - Subalpine Fir Zone in the southern interior of British Columbia in September 1995 and recovered just before snow melt in June 1996. Fifty-two and 86% of the viable spruce and fir seed, respectively, had germinated before snowmelt. Germination under snow may be an adaptation of these high-elevation species to short cool growing seasons. Seed viability at recovery was significantly lower on undisturbed forest floor seed beds (spruce, 13%; fir, 12%) than on exposed mineral soil (spruce, 57%; fir, 42%). Viability of seed placed on nurse logs was 38 and 23% for spruce and fir, respectively. Isolation from ungerminated seed yielded a Rhizoctonia sp., an as yet unidentified black mold at high frequencies, and several other seed pathogens at low frequency. Multiple linear regression of the frequency of isolation of Rhizoctonia and black mold on seed viability was highly significant for both tree species. Seed pathogens appear to cause a major loss of seed and seedlings in these forests, and this may explain both the common occurrence of regeneration on nurse logs and the requirement of mineral soil seed beds for adequate regeneration.

scholarly journals Natural and Advance Regeneration of Engelmann Spruce and Subalpine Fir Compared 21 Years After Site Treatment

1980 ◽  
Vol 56 (2) ◽  
pp. 55-57 ◽  
Author(s):  
L. J. Herring ◽  
R. G. McMinn
Keyword(s):  
Natural Regeneration ◽  
Mineral Soil ◽  
Poor Performance ◽  
Abies Lasiocarpa ◽  
Subalpine Fir ◽  
Engelmann Spruce ◽  
Advance Regeneration ◽  
Residual Tree ◽  
Mean Current ◽  
Picea Engelmanni

The mean height of Engelmann spruce (Picea engelmanni Parry) advance growth 21 years after release by overstorey harvesting and residual tree felling, was eight times that of natural regeneration established following brush blade scarification. Subalpine fir (Abies lasiocarpa (Hook.) Nutt.) advance growth was nine times taller than natural regeneration established on scarified soil. Mean current annual height increment of Engelmann spruce and subalpine fir advance growth was 39 and 34 cm, respectively, compared with only 7 cm for natural regeneration on scarified soil. The performance gap does not appear to be narrowing. The poor performance of natural regeneration on mineral soil exposed by blade scarification is attributed to removal of organic and top mineral soil horizons beyond the immediate reach of seedlings. These soil layers remained available to the advance growth. Consideration should be given to preserving advance growth when scarification may be inappropriate.

Light and temperature differentially colimit subalpine fir and Engelmann spruce seedling growth in partial-cut subalpine forests

2004 ◽  
Vol 34 (1) ◽  
pp. 249-260 ◽  
Author(s):  
Cleo C Lajzerowicz ◽  
Michael B Walters ◽  
Marek Krasowski ◽  
Hugues B Massicotte
Keyword(s):  
Soil Temperature ◽  
Seedling Growth ◽  
Light Availability ◽  
N Availability ◽  
Abies Lasiocarpa ◽  
Soil N ◽  
Subalpine Forests ◽  
Subalpine Fir ◽  
Engelmann Spruce ◽  
Soil Temperatures

We compared the relative impacts of light, soil N, and soil temperature on Engelmann spruce (Picea engelman nii Parry ex Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) seedling growth by quantifying (i) microsite environment-growth relationships for N-fertilized and unfertilized planted seedlings in shelterwood, patch cut, and clearcut harvest treatments and (ii) growth, photosynthesis, and biomass allocation for greenhouse-grown seedlings at 5, 10, and 15 °C soil temperatures. Fertilization did not affect seedling growth. Furthermore, soil N availability did not vary among harvest treatments. In contrast, clearcut compared with shelterwood seedlings had greater mass (fivefold), light availability (twofold), and soil temperatures (1.6 °C). Across harvest treatments, spruce and fir mass increased linearly to 100% open-sky light (R2 = 0.51 and 0.57, respectively), and temperature and light combined explained more variation in mass than light alone (adjusted R2 = 0.58 for both species). Spruce growth was more sensitive to temperature than fir in both field and greenhouse experiments. Diminished growth at low soil temperature was associated with lower photosynthesis and not lower leaf fraction. Thus, soil temperature and light colimit seedling growth in subalpine forests, but responses were species-specific and consistent with microenvironment differences in spruce and fir regeneration niches.

Performance of planted Engelmann spruce and subalpine fir seedlings in British Columbia's southern mountains

2006 ◽  
Vol 82 (1) ◽  
pp. 84-94 ◽  
Author(s):  
C C Lajzerowicz ◽  
A. Vyse ◽  
M. Jull ◽  
T. Newsome
Keyword(s):  
British Columbia ◽  
Seedling Survival ◽  
High Elevation ◽  
Abies Lasiocarpa ◽  
Individual Tree ◽  
Relative Growth Rates ◽  
Subalpine Fir ◽  
Engelmann Spruce ◽  
South Central ◽  
Soil Temperatures

We compared survival and growth of planted seedlings of Engelmann spruce and subalpine fir across a range of harvest opening sizes (> 10 ha, 1 ha, 0.2 ha, 0.1 ha, 0.03 ha and individual tree selection) from three silvicultural systems trials in high-elevation spruce – subalpine fir forests in south-central British Columbia. Climatic patterns and growing season air and soil temperatures were similar across sites. Seedling survival decreased with opening size. Local site climates, influenced by aspect and moisture and air drainage, were more influential than elevation. Seedling growth was best in large openings and similar in opening sizes from 1 ha to 0.1 ha. Smaller openings created by group selection and individual tree selection methods were not favourable for successful planting at elevations close to timberline. The two species had similar absolute and relative growth rates but spruce responded more strongly to better growing environments. Key words: planted seedlings, Engelmann spruce, Picea engelmannii Parry ex Engelm., subalpine fir, Abies lasiocarpa (Hook.) Nutt., opening size, elevation effects, silvicultural systems, British Columbia, mountain forests

Effects of harvesting on fine root biomass and decomposition in an Engelmann spruce – subalpine fir forest

2003 ◽  
Vol 33 (5) ◽  
pp. 847-853 ◽  
Author(s):  
Sylvia E Welke ◽  
Graeme D Hope ◽  
Gary A Hunt
Keyword(s):  
Root Biomass ◽  
Fine Root ◽  
Timber Harvesting ◽  
High Elevation ◽  
Fine Root Biomass ◽  
Nutrient Concentrations ◽  
Root Dynamics ◽  
Subalpine Fir ◽  
Root Longevity ◽  
Engelmann Spruce

The effect of timber harvesting on the biomass, nutrient standing crop, and decomposition of fine roots (<2 mm) was studied in a high elevation, Engelmann spruce (Picea engelmannii Parry ex Engelm.) – subalpine fir (Abies lasiocarpa (Hook.) Nutt.) forest. Root dynamics were compared in openings of different sizes. The sequential core method was used to collect fine root samples over 4 years. Differences in fine root biomass between opening sizes were most significant for the active fine root portion and were most pronounced in the fall compared with the spring. Active fine root biomass was significantly lower in the 10-ha clearcuts (164 kg/ha) compared with control plots (275 kg/ha). Furthermore, active fine root biomass was often lower in the 1.0-ha opening than in the 0.1-ha and control plots. A similar trend was established for inactive fine root biomass, although this was not consistent over sampling years. Nutrient concentrations of K, but no other elements, were higher in control plots. Nutrient standing crops, however, followed trends observed in fine root biomass. In the 10-ha clearcuts, the largest changes in fine root biomass occurred at the edge of the opening. The findings suggest that small (<10 ha) cutblocks may maintain greater fine root longevity.

Nitrogen storage and availability during stand development in a New Zealand Nothofagus forest

2002 ◽  
Vol 32 (2) ◽  
pp. 344-352 ◽  
Author(s):  
P W Clinton ◽  
R B Allen ◽  
M R Davis
Keyword(s):  
New Zealand ◽  
Forest Floor ◽  
Woody Debris ◽  
Mineral Soil ◽  
Stand Development ◽  
N Availability ◽  
Net N Mineralization ◽  
Nitrogen Storage ◽  
Nothofagus Forest ◽  
Mature Stands

Stemwood production, N pools, and N availability were determined in even-aged (10, 25, 120, and >150-year-old) stands of a monospecific mountain beech (Nothofagus solandri var. cliffortioides (Hook. f.) Poole) forest in New Zealand recovering from catastrophic canopy disturbance brought about by windthrow. Nitrogen was redistributed among stemwood biomass, coarse woody debris (CWD), the forest floor, and mineral soil following disturbance. The quantity of N in stemwood biomass increased from less than 1 kg/ha in seedling stands (10 years old) to ca. 500 kg/ha in pole stands (120 years old), but decreased in mature stands (>150 years old). In contrast, the quantity of N stored in CWD declined rapidly with stand development. Although the mass of N stored in the forest floor was greatest in the pole stands and least in the mature stands, N availability in the forest floor did not vary greatly with stand development. The mass of N in the mineral soil (0–100 mm depth) was also similar for all stands. Foliar N concentrations, net N mineralization, and mineralizable N in the mineral soil (0–100 mm depth) showed similar patterns with stage of stand development, and indicated that N availability was greater in sapling (25 years old) and mature stands than in seedling and pole stands. We conclude that declining productivity in older stands is associated more with reductions in cation availability, especially calcium, than N availability.

Segregation of allozyme loci in megagametophytes of Engelmann spruce and subalpine fir

Genome ◽  
1988 ◽  
Vol 30 (2) ◽  
pp. 103-107 ◽  
Author(s):  
Kathleen L. Shea
Keyword(s):  
Natural Populations ◽  
Segregation Ratio ◽  
Colorado Front Range ◽  
Abies Lasiocarpa ◽  
Front Range ◽  
Subalpine Fir ◽  
Polymorphic Loci ◽  
Engelmann Spruce ◽  
Low Levels ◽  
Allozyme Loci

Segregation ratios and linkage of 10 allozyme loci were examined in haploid megagametophytes obtained from natural populations of Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) in the Colorado Front Range. For data pooled over trees, the 1:1 segregation ratio expected at Mendelian loci was obtained for five polymorphic loci in 32 Engelmann spruce trees and for seven polymorphic loci in 40 subalpine fir trees. The Gdh and Idh loci in spruce were very tightly linked: no recombinants were detected among 60 megagametophytes of trees heterozygous for both loci. In fir only the Aco and Pgm-1 loci were linked, with an estimated recombination rate of 0.317 ± 0.073. The low levels of among-tree heterogeneity and of segregation distortion found in these populations suggest that reliable estimates of both genetic variation and outcrossing rates can be obtained using allozyme data from these wind-pollinated species.Key words: segregation, linkage, allozymes, Engelmann spruce, subalpine fir.

Inonotus tomentosus and the dynamics of unmanaged and partial-cut wet sub-boreal spruce–fir forests

2007 ◽  
Vol 37 (12) ◽  
pp. 2663-2676 ◽  
Author(s):  
J. E. (Ted) Newbery ◽  
Kathy J. Lewis ◽  
Michael B. Walters
Keyword(s):  
Picea Glauca ◽  
Dead Wood ◽  
Basal Area ◽  
Tree Density ◽  
Small Scale ◽  
Abies Lasiocarpa ◽  
Partial Cutting ◽  
Subalpine Fir ◽  
Engelmann Spruce ◽  
Live Tree

For wet sub-boreal spruce–fir forests (white spruce ( Picea glauca (Moench) Voss) × Engelmann spruce ( Picea engelmannii Parry ex Engelm.) – subalpine fir ( Abies lasiocarpa (Hook.) Nutt.)) in east-central British Columbia, we asked (i) do compositional and structural dynamics differ for unmanaged (UN) and partial-cut (PC) (50% removal 45 years before measurement) forests and (ii) how does Inonotus tomentosus Fr. (Teng) affect these dynamics? Inonotus tomentosus infected stands had 17% less spruce basal area (P = 0.059) than uninfected stands, but PC did not exacerbate I. tomentosus effects. PC and UN had similar live tree density, but UN had lower dead tree density. In all stands, snag longevity was typically <32 years, and ~40 years was required for dead wood to reach decay stage 3 or greater. UN was characterized by variable severity disturbances averaging ~8% of the canopy per decade. Management implications include the following: (i) harvest systems designed to emulate small-scale disturbance could remove trees at 8% of the canopy per decade, varied spatiotemporally, (ii) emulating dead wood abundance with partial cutting may be difficult given the impacts of partial cutting on dead wood abundance, and (iii) forests with moderate levels of I. tomentosus should not respond differently to harvesting than uninfected forests and thus require no special management.

scholarly journals Distribution of the Balsam Woolly Adelgid in Idaho

2000 ◽  
Vol 15 (4) ◽  
pp. 227-231 ◽  
Author(s):  
R.L. Livingston ◽  
J.E. Dewey ◽  
D.P. Beckman ◽  
L.E. Stipe
Keyword(s):  
North America ◽  
High Elevation ◽  
The State ◽  
Abies Lasiocarpa ◽  
Subalpine Fir ◽  
Northeastern North America ◽  
Aerial Surveys ◽  
Host Type ◽  
Ecological Values ◽  
Balsam Woolly Adelgid

Abstract The balsam woolly adelgid (Adelges piceae) was introduced from Europe to northeastern North America in about 1900. In 1983, it was discovered infesting fir trees in Idaho. Since then, aerial and ground surveys have documented its spread in Idaho over an area of approximately 14,000 mi2 (8,960,000 ac). It now covers most of the central one-third of the state. Aerial surveys in 1997 and 1998 identified about 125,000 ac of host type with dead or damaged trees. Subalpine fir (Abies lasiocarpa) is a critical species in many high elevation areas. The effects of the balsam wooly adelgid on aesthetics, hydrology, and other ecological values can be very important. The adelgid is likely to continue its spread throughout subalpine fir forests of Idaho and neighboring states. West. J. Appl. For. 15(4):227-231,

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