scholarly journals Convergence of leaf display and photosynthetic characteristics of understory Abies amabilis and Tsuga heterophylla in an old-growth forest in southwestern Washington State, USA

2009 ◽  
Vol 29 (8) ◽  
pp. 989-998 ◽  
Author(s):  
H. Ishii ◽  
K.-I. Yoshimura ◽  
A. Mori
Keyword(s):  
Tsuga Heterophylla ◽  
Washington State ◽  
Photosynthetic Characteristics ◽  
Old Growth ◽  
Abies Amabilis ◽  
Old Growth Forest

Canopy openness and leaf area in chronosequences of coastal temperate rainforests

2000 ◽  
Vol 30 (2) ◽  
pp. 239-256 ◽  
Author(s):  
Gordon W Frazer ◽  
J A Trofymow ◽  
Kenneth P Lertzman
Keyword(s):  
Leaf Area ◽  
Tsuga Heterophylla ◽  
Thuja Plicata ◽  
Canopy Openness ◽  
East Side ◽  
The West ◽  
Old Growth ◽  
Regional Patterns ◽  
Forest Canopies ◽  
Old Growth Forest

We examined spatial and temporal differences in canopy openness and effective leaf area (Le) in a series of eight forest chronosequences located on southern Vancouver Island, British Columbia. Structural attributes were measured on the west and east side of the island in immature, mature, and old-growth stands using hemispherical photography and the LAI-2000 plant canopy analyzer (PCA). Old-growth forest canopies were distinct from those of younger stands: they were more open, more heterogeneous in their openness, and maintained a lower stand Le. Although the overall developmental trajectories of forests were similar across the study sites, site-to-site differences in the rate and magnitude of these temporal changes indicated that site-specific factors also play a significant role in determining the character of forest canopies and their development. The most significant changes in canopy structure did not emerge until the later stages of stand development (150-200 years). Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) dominated east-side forests were, on average, more open, more heterogeneous, and had a lower stand Le than the stands dominated by western hemlock (Tsuga heterophylla (Raf.) Sarg.) and western redcedar (Thuja plicata Donn.) forming the west-side chronosequences. Shoot clumping, along with other evidence, suggested that species-related differences in leaf display and the geometry of branching structure might have contributed significantly to these regional patterns.

scholarly journals Height growth and vertical development of an old-growth Pseudotsuga-Tsuga forest in southwestern Washington State, U.S.A.

2000 ◽  
Vol 30 (1) ◽  
pp. 17-24 ◽  
Author(s):  
Hiroaki Ishii ◽  
Joel H Reynolds ◽  
E David Ford ◽  
David C Shaw
Keyword(s):  
Future Development ◽  
Growth Rates ◽  
Forest Canopy ◽  
Size Structure ◽  
Tree Height ◽  
Tsuga Heterophylla ◽  
Height Growth ◽  
Washington State ◽  
Thuja Plicata ◽  
Old Growth

A detailed analysis of diameter-height relationships was applied to an old-growth Pseudotsuga menziesii (Mirb.) Franco var. menziesii - Tsuga heterophylla (Raf.) Sarg. forest in southwestern Washington State, U.S.A., to predict future development of vertical stratification among tree species. Differences among species in relative abundance and size structure resulted in diameter-height regressions of varying certainty and stability. Damage and shading had negative impacts on predicted heights and estimates of maximum attainable height (Hmax) in all species. However, species varied as to the main causes and size dependency of damage in relation to tree height. Current height-growth rates of the upper canopy species declined with increasing tree height, reaching minimum values near the predicted Hmax. The future development of the forest canopy would involve a slow invasion of the upper canopy by Tsuga heterophylla and Thuja plicata Donn ex D. Don, as P. menziesii are near their maximum attainable height, and Abies amabilis Dougl. ex Forbes and Taxus brevifolia Nutt. are restricted to the middle to lower canopy. However, if current height-growth rates continue, P. menziesii should maintain its dominant status in the upper canopy for at least another century.

Spatial distribution and succession of epiphytes on Tsuga heterophylla (western hemlock) in an old-growth Douglas-fir forest

2000 ◽  
Vol 78 (7) ◽  
pp. 957-968 ◽  
Author(s):  
Betsy Lyons ◽  
Nalini M Nadkarni ◽  
Malcolm P North
Keyword(s):  
Forest Canopy ◽  
Spatial Scales ◽  
Coniferous Forest ◽  
Tsuga Heterophylla ◽  
Forest Understory ◽  
Western Hemlock ◽  
Old Growth ◽  
Old Growth Forest ◽  
Crown Structure ◽  
Large Trees

We examined the distribution and abundance of nonvascular epiphytes on western hemlock trees in an old-growth coniferous forest focusing on patterns of epiphyte distribution at different spatial scales, epiphyte abundance amongst trees differing in size, and crown structures associated with epiphyte abundance. Total epiphyte cover was greatest in four canopy microhabitats: the upper canopy strata, crowns of large trees, lower crown branches, and inner branch plots. Epiphyte functional groups were stratified vertically within the stand and horizontally within branches. Alectorioid and "other" lichens were most abundant in the upper canopy and outer branch plots. Cyanolichens and Sphaerophorus globosus (Huds.) Vain. were most abundant in the lower to mid canopy. Although cyanolichens were most abundant in middle branch plots, Sphaerophorus was most abundant in inner branch plots. Bryophytes were most abundant in the lower canopy and inner branch plots. At the stand level, canopy height and tree size were the main influences on epiphytes. Within trees, plots closer to the tree trunk and lower in the crown had the greatest abundance of epiphytes. In this forest, understory trees were colonized first by bryophytes, not by alectorioid and "other" lichens as is common for small trees in young stands.Key words: epiphyte succession, lichens, western hemlock, old growth, forest canopy, crown structure.

Macrolichen colonization on 120–140 year old Tsuga heterophylla in wet temperate rainforests of central-interior British Columbia: a comparison of lichen response to even-aged versus old-growth stand structures

2004 ◽  
Vol 36 (3-4) ◽  
pp. 235-247 ◽  
Author(s):  
David N. RADIES ◽  
Darwyn S. COXSON
Keyword(s):  
British Columbia ◽  
Forest Harvesting ◽  
Tsuga Heterophylla ◽  
Limiting Factor ◽  
Forest Stands ◽  
Old Growth ◽  
Old Growth Forest ◽  
Growth Constraints ◽  
Rotation Age ◽  
Temperate Rainforests

Canopy lichen abundance was assessed by size class on regenerating hemlocks, comparing trees of similar size and age (c. 120–140 yrs) growing in the understorey of old-growth cedar-hemlock stands with those growing in adjacent even-aged hemlock stands (natural origin patches c. 1–3 ha in size). Five chlorolichen taxa were associated with old-growth understorey trees: Cavernularia hultenii, Hypogymnia vitatta, Parmelia hygrophila, Platismatia norvegica, and Usnea spp. Lobaria pulmonaria was the most abundant cyanolichen on regenerating hemlock in the old-growth forest stands, particularly in lower canopy (under 12 m) exposures. However, other cyanolichen taxa such as Nephroma helveticum, Sticta fulginosa, and Pseudocyphellaria anomala, reached their greatest abundance at mid-canopy (12–24 m) positions. Smaller cyanolichen thalli (<9 cm2) were abundant on regenerating hemlocks across all canopy positions in the old-growth forest, raising the question as to whether or not cyanolichen thalli in mid- to upper-canopy environments represented long-established individuals facing severe growth constraints, or were simply thalli that had experienced higher rates of fragmentation, and thus did not achieve larger sizes. In comparison, cyanolichens of all taxa were essentially absent from the small-patch even-aged forest stands. Given that dispersal of propagules was not likely a major limiting factor, these 120–140 year old even-age stands may not yet have attained sufficient old-growth characteristics (especially canopy microclimate and canopy throughflow enrichment) to support cyanolichen growth. These findings have major conservation biology implications for wet interior cedar-hemlock forests in British Columbia, where forest harvesting is creating a mosaic of even-aged stands, whose projected age at the time of next harvest (rotation age) will be 120 years or less.

Tradable Disturbance Permits for Old-growth Forest Conservation: Experimental Evaluation of Implementation Options

2017 ◽  
Vol 7 (1-2) ◽  
pp. 73-107
Author(s):  
Orsolya Perger ◽  
Curtis Rollins ◽  
Marian Weber ◽  
Wiktor Adamowicz ◽  
Peter Boxall
Keyword(s):  
Experimental Evaluation ◽  
Forest Conservation ◽  
Old Growth ◽  
Old Growth Forest

Old-growth forest reserves in Slovenia: the past, present, and future

2012 ◽  
Vol 163 (6) ◽  
pp. 240-246 ◽  
Author(s):  
Thomas A. Nagel ◽  
Jurij Diaci ◽  
Dusan Rozenbergar ◽  
Tihomir Rugani ◽  
Dejan Firm
Keyword(s):  
Stand Structure ◽  
Growth Conditions ◽  
Ecosystem Functions ◽  
Future Research ◽  
Old Growth ◽  
Forest Reserves ◽  
The Past ◽  
Old Growth Forest ◽  
Forest Remnants ◽  
Basic Characteristics

Old-growth forest reserves in Slovenia: the past, present, and future Slovenia has a small number of old-growth forest remnants, as well as many forest reserves approaching old-growth conditions. In this paper, we describe some of the basic characteristics of these old-growth remnants and the history of their protection in Slovenia. We then trace the long-term development of research in these old-growth remnants, with a focus on methodological changes. We also review some of the recent findings from old-growth research in Slovenia and discuss future research needs. The conceptual understanding of how these forests work has slowly evolved, from thinking of them in terms of stable systems to more dynamic and unpredictable ones due to the influence of natural disturbances and indirect human influences. In accordance with this thinking, the methods used to study old-growth forests have changed from descriptions of stand structure to studies that address natural processes and ecosystem functions.

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