Secondary disturbance following a deposit of volcanic tephra: A 30 year record from old-growth forest understory

Forest disturbance is usually described by effects on trees, and small disturbances to forest understory are seldom studied. Nevertheless, effective analyses of succession need to consider both stand-replacing and subsequent “secondary” disturbances in both canopy and understory. We estimated characteristics of 13 types of secondary disturbance in old-growth forest understory, and of canopy cover, after the 1980 tephra (aerially transported volcanic ejecta) deposition from Mount St. Helens, Washington. We sampled 100 1-m2 plots at each of four sites for vegetation change and types of disturbance at ten times from 1980-2010; we sampled tree canopy above each plot in 1980 and 2016. The number of canopy gaps increased 23 % and mean gap dimension 68 % during 36 years, mostly from loss of Abies amabilis. Secondary disturbance in understory affected 1.4 % of stand area per year. The areas affected by soil disturbance and effects of woody litter were similar. Erosion, greater in deep than in shallow tephra, peaked in 1981, whereas most litter-caused disturbances increased after 2000. Less frequent litter-based disturbances covered greater area. Our results differ from conclusions about non-volcanic understory disturbances. Secondary disturbances are variable, need more study, and are likely to affect many other systems.

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Communities of aquatic insects of old-growth and clearcut coastal headwater streams of varying flow persistence

Canadian Journal of Forest Research ◽

10.1139/x03-089 ◽

2003 ◽

Vol 33 (8) ◽

pp. 1416-1432 ◽

Cited By ~ 28

Author(s):

Karen Price ◽

Arlene Suski ◽

Joanna McGarvie ◽

Barbara Beasley ◽

John S Richardson

Keyword(s):

Aquatic Insects ◽

Algal Biomass ◽

Headwater Streams ◽

Canopy Cover ◽

Ephemeral Streams ◽

Aquatic Communities ◽

Old Growth ◽

Organic Detritus ◽

Temporary Streams ◽

Old Growth Forest

Headwater streams, varying in flow persistence from ephemeral to intermittent to perennial, provide the tightest coupling between water and land, yet they often receive the least protection during forest management. We described communities of aquatic insects in perennial, intermittent, and ephemeral channels surrounded by old-growth forest and 4- to 8-year-old clearcuts in Clayoquot Sound, British Columbia, to determine whether temporary streams have unique aquatic communities and to examine the short-term impacts of harvesting. We measured flow persistence, stream size, canopy cover, organic detritus, and algal biomass in 19 streams. We sampled aquatic invertebrates with a combination of emergence cages and kicknet samples. Temporary and old-growth streams had more organic detritus and a higher abundance of shredders. Perennial and clearcut streams had a higher abundance of some algal grazers, but not higher algal biomass. Insect richness was similar in intermittent and perennial streams of each seral stage but lower in ephemeral streams. Intermittent streams contained four taxa not found in the other stream classes; perennial and ephemeral streams had none. Communities of aquatic insects differed between streams surrounded by clearcuts and old growth, and varied with continuity of flow.

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The effect of soil disturbance on growth and ectomycorrhizae of Douglas-fir and western hemlock seedlings: a greenhouse bioassay

Canadian Journal of Forest Research ◽

10.1139/x82-050 ◽

1982 ◽

Vol 12 (2) ◽

pp. 343-353 ◽

Cited By ~ 50

Author(s):

M. Meyer Schoenberger ◽

D. A. Perry

Keyword(s):

Soil Disturbance ◽

Douglas Fir ◽

Western Hemlock ◽

Root Tips ◽

Old Growth ◽

Clear Cut ◽

Old Growth Forest ◽

Litter Leachate ◽

Oregon Cascades ◽

Tip Formation

In a greenhouse bioassay of soils from the central Oregon Cascades, Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings had the most total and ectomycorrhizal root tips when grown in soil from an unburned clear-cut and the least when grown in soil from (i) a 20-year-old plantation that had been clear-cut and burned in the late 1950's and (ii) one old-growth forest. Tip formation was intermediate in soil from a second old-growth forest, a recently burned clear-cut, and a 40-year-old natural burn. Root weights followed the same trend, but top weights did not differ among the various soils. Ectomycorrhizal and total root tips of western hemlock (Tsugaheterophylla (Raf.) Sarg.) were lowest in soils from the plantation and recently burned clear-cut. Unlike Douglas-fir, western hemlock's tip production was not greater in the unburned clear-cut than in the old-growth forest soils. In this species, both top and root weights varied according to soil, with the largest seedlings produced in soil from the unburned clear-cut. With both species, there was a significant interaction between ectomycorrhizal type and soil type. Cenococcumgeophilum Fr. predominated on western hemlock and was reduced in soils from the burned clear-cut and plantation. In comparison with the mean for all soils, ectomycorrhizal types that predominated on Douglas-fir were enhanced in the unburned clear-cut soil and reduced in one old-growth soil, an effect apparently related to litter leachate.

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Relations between tree canopy composition and understorey vegetation in a European beech-sessile oak old growth forest in Western Romania

Biologia ◽

10.1515/biolog-2017-0165 ◽

2017 ◽

Vol 72 (12) ◽

Cited By ~ 1

Author(s):

Michaela Dölle ◽

Any Mary Petritan ◽

Iovu Adrian Biris ◽

Ion Catalin Petritan

Keyword(s):

European Beech ◽

Tree Canopy ◽

Herb Layer ◽

Natural Forests ◽

Canopy Layer ◽

Old Growth ◽

Understorey Vegetation ◽

Sessile Oak ◽

Old Growth Forest ◽

Western Romania

AbstractThe diversity relationship between tree and herb layer has often been investigated, but the results are contradictory. Moreover, few studies of deciduous European species have been conducted to date in natural or near-natural forests, while such studies in old-growth forest with considerable co-dominance of oak are missing.In one of the best preserved natural European beech-sessile oak forests (Runcu-Grosi Natural Reserve, Western Romania) we investigated whether there is a correlation between canopy-layer diversity and herb-layer diversity. Structural diversity, vegetation composition, ecological and functional traits were evaluated. Our results show that the herb-layer diversity is higher under canopy with greater tree-layer diversity, and the diversity of both layers depend on whether the overstorey is dominated by beech or sessile oak. Herb layers of plots with oak co-dominance showed higher indicator values for light and temperature, and a higher proportion of graminoides and shrub species. In contrast, herb-layer in beech plots is dominated by juvenile trees, mainly beech and competitive herb species. Oak plots are characterised by a generally more evenly distributed herb-layer composition. Species richness of herb-layer was higher under a diversely structured overstorey, which was mainly achieved when oak was present in the canopy, and correlated negatively with litter thickness, which was highest in beech plots. We conclude that the identity of the dominant canopy species is most important for herb layer species composition and diversity. Furthermore, the plots with oak occurrence in the overstorey even with weak proportion (around 20% of stand basal area) features a higher biodiversity of species in the understorey.

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Buried propagules in an old-growth forest and their response to experimental disturbances

Canadian Journal of Botany ◽

10.1139/b90-146 ◽

1990 ◽

Vol 68 (5) ◽

pp. 1156-1162 ◽

Cited By ~ 14

Author(s):

Cheryl A. Ingersoll ◽

Mark V. Wilson

Keyword(s):

Forest Disturbance ◽

Seedling Emergence ◽

Abundant Species ◽

Significant Decline ◽

Control Treatment ◽

Old Growth ◽

Greenhouse Condition ◽

Old Growth Forest ◽

Surface Burning ◽

Experimental Treatments

Soil blocks collected from an old-growth Pseudotsuga menziesii forest were subjected to three types of disturbances (shade removal, surface burning, and soil churning) in a factorial experiment. Most émergents (88%) were vegetative sprouts. Total emergence and emergence of vegetative sprouts were significantly higher in the undisturbed (control) treatment than in any other treatment. As intensity of disturbance (measured by the number of disturbance factors applied) increased, the number of emergents declined. Exposure to sun caused a significant decline in emergence of each of the six most abundant species; the effects of burning and churning varied by species. Burning decreased the emergence of species with shallow regenerating structures. None of the experimental treatments significantly affected seedling emergence. Density of émergents (both seedlings and vegetative sprouts) was higher under greenhouse condition (411.7/m2) than in the experimental treatments (94.6/m2), indicating that greenhouse emergence is more suitable for quantifying the buried propagule bank. Key words: seed bank, propagules, old-growth forest, disturbance, fire.

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Old-Growth Forest Disturbance in the Ukrainian Carpathians

Forests ◽

10.3390/f11020151 ◽

2020 ◽

Vol 11 (2) ◽

pp. 151 ◽

Cited By ~ 2

Author(s):

Benedict D. Spracklen ◽

Dominick V. Spracklen

Keyword(s):

Image Analysis ◽

Protected Areas ◽

Protected Area ◽

Forest Disturbance ◽

Satellite Image ◽

Old Growth ◽

Old Growth Forest ◽

Western Ukraine ◽

Future Loss ◽

Satellite Image Analysis

Human activity has greatly reduced the area of old-growth forest in Europe, with some of the largest remaining fragments in the Carpathian Mountains of south-western Ukraine. We used satellite image analysis to calculate old-growth forest disturbance in this region from 2010 to 2019. Over this period, we identified 1335 ha of disturbance in old-growth forest, equivalent to 1.8% of old-growth forest in the region. During 2015 to 2019, the average annual disturbance rate was 0.34%, varying with altitude, distance to settlements and location within the region. Disturbance rates were 7–8 times lower in protected areas compared to outside of protected areas. Only one third of old-growth forest is currently within protected areas; expansion of the protected area system to include more old-growth forests would reduce future loss. A 2017 law that gave protection to all old-growth forest in Ukraine had no significant impact on disturbance rates in 2018, but in 2019 disturbance rates reduced to 0.19%. Our analysis is the first indication that this new legislation may be reducing loss of old-growth forest in Ukraine.

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

Canadian Journal of Botany ◽

10.1139/b00-064 ◽

2000 ◽

Vol 78 (7) ◽

pp. 957-968 ◽

Cited By ~ 14

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.

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

Strategic Behavior and the Environment ◽

10.1561/102.00000074 ◽

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

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Southeast Alaska old-growth forest stem map data collected in 1964 on ten 1.42 hectare plots

Forest Service Research Data Archive ◽

10.2737/rds-2020-0025 ◽

2020 ◽

Author(s):

Eryn E. Schneider ◽

Justin S. Crotteau ◽

Andrew J. Larson

Keyword(s):

Old Growth ◽

Southeast Alaska ◽

Old Growth Forest ◽

Map Data

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

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2012.0240 ◽

2012 ◽

Vol 163 (6) ◽

pp. 240-246 ◽

Cited By ~ 7

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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