Influences of gap microheterogeneity on the regeneration of Nothofagus pumilio in a xeric old-growth forest of northwestern Patagonia, Argentina

2000 ◽  
Vol 30 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Karin Heinemann ◽  
Thomas Kitzberger ◽  
Thomas T Veblen
Keyword(s):  
Environmental Heterogeneity ◽  
Woody Debris ◽  
Tree Regeneration ◽  
Timber Species ◽  
Nothofagus Pumilio ◽  
Old Growth ◽  
Northern Patagonia ◽  
Old Growth Forest ◽  
Demographic Bottleneck ◽  
Gap Creation

We experimentally examined the influences of within-gap environmental heterogeneity on regeneration patterns of Nothofagus pumilio (Poepp. & Endl.) Krasser near the xeric limit of its distribution in northern Patagonia, Argentina. Results from this xeric old-growth forest are compared with patterns previously described for the same species in mesic forests. Survival of N. pumilio seedlings beneath tree-fall gaps in this relatively xeric forest appears to be strongly influenced by moisture availability. Seedlings and saplings that have survived this demographic bottleneck are found at microsites where soil water potentials are higher, such as in the shady northern edges of tree-fall gaps (Ψ = -0.46 MPa compared with less than -0.6 MPa in other gap positions) and on coarse woody debris (Ψ = -0.29 MPa, compared with -0.51 MPa on the forest floor). Although gap creation in this dry N. pumilio forest is favorable to tree regeneration by releasing light resources, decreased water resources may switch the system from a light- to a water-limited system in some positions of the gap. This may explain the lack of regeneration of N. pumilio often observed after creation of large gaps towards the xeric end of its range and needs to be considered in the management of this important timber species.

Home range and habitat use by Magellanic Woodpeckers in an old-growth forest of Patagonia

2014 ◽  
Vol 44 (10) ◽  
pp. 1265-1273 ◽  
Author(s):  
Valeria Ojeda ◽  
Laura Chazarreta
Keyword(s):  
Home Range ◽  
Woody Debris ◽  
Home Range Size ◽  
Habitat Characteristics ◽  
Home Ranges ◽  
Nothofagus Pumilio ◽  
Old Growth ◽  
Forest Patches ◽  
Argentine Patagonia ◽  
Old Growth Forest

The Magellanic Woodpecker (Campephilus magellanicus (King, 1827)) is a large, vulnerable species exhibiting geographic range retraction. We analyzed the size and location of forest areas used by these woodpeckers in consecutive years (2010–2012), as related to habitat characteristics, in an old-growth lenga (Nothofagus pumilio (Poepp et Endl.) Krasser) forest of Argentine Patagonia. Woodpeckers were tracked during the postbreeding season, and forest features were evaluated in plots within territories. Woodpecker density was 1.01 territories·100 ha–1. The resident population apparently saturates the forest available in the study site; hence, territorial disputes were frequent between all pairs of adjacent families. Families used 39.3 ± 13.6 ha during the postreproductive season and 63.2 ± 12.3 ha across the three seasons, with interannual variability in both location and size of the areas used. Abundances of large live trees and of coarse woody debris were correlated with smaller, presumably high-quality, home ranges. Other forest attributes that are often important in woodpecker habitat (e.g., snag density) had little relationship with home-range size, but the high availability of resources in old-growth forests may mask their potential importance in a poorer quality habitat. Our results show that Magellanic Woodpecker family groups require a minimum of 100 ha in old-growth forest habitat; thus, forest patches in less favourable forest conditions (e.g., younger, managed, fragmented, mixed forests) should probably be much larger to support a resident pair or family. This habitat size would be a provisional minimum threshold to be used in management decisions involving the forests of Patagonia until alternative figures are derived from studies across multiple forest types.

scholarly journals Bryophyte Conservation in Managed Boreal Landscapes: Fourteen-Year Impacts of Partial Cuts on Epixylic Bryophytes

2021 ◽  
Vol 4 ◽  
Author(s):  
Jeffrey Opoku-Nyame ◽  
Alain Leduc ◽  
Nicole J. Fenton
Keyword(s):  
Species Composition ◽  
Coarse Woody Debris ◽  
Black Spruce ◽  
Woody Debris ◽  
Permanent Plots ◽  
Old Growth ◽  
Clear Cut ◽  
Old Growth Forest ◽  
Old Growth Forests ◽  
Over Time

Clear cut harvest simplifies and eliminates old growth forest structure, negatively impacting biodiversity. Partial cut harvest has been hypothesized (1) to have less impact on biodiversity than clear cut harvest, and (2) to encourage old growth forest structures. Long-term studies are required to test this hypothesis as most studies are conducted soon after harvest. Using epixylic bryophytes as indicators, this study addresses this knowledge gap. Fourteen years after harvest, we examined changes in epixylic bryophyte community composition richness and traits, and their microhabitats (coarse woody debris characteristics and microclimate) along an unharvested, partial cuts and clear cuts harvest treatment in 30 permanent plots established in the boreal black spruce (Picea mariana) forests of northwestern Quebec, Canada. Our results were compared to those of an initial post-harvest study (year 5) and to a chronosequence of old growth forests to examine species changes over time and the similarity of bryophyte communities in partial cut and old growth forests. Coarse woody debris (CWD) volume by decay class varied among harvest treatments with partial cuts and clear cuts recording lower volumes of early decay CWD. The epixylic community was richer in partial cuts than in mature unharvested forests and clear cuts. In addition, species richness and overall abundance doubled in partial and clear cuts between years 5 and 14. Species composition also differed among treatments between years 5 and 14. Furthermore, conditions in partial cut stands supported small, drought sensitive, and old growth confined species that are threatened by conditions in clear cut stands. Lastly, over time, species composition in partial cuts became more similar to old growth forests. Partial cuts reduced harvest impacts by continuing to provide favorable microhabitat conditions that support epixylic bryophytes. Also, partial cut harvest has the potential to encourage old growth species assemblages, which has been a major concern for biodiversity conservation in managed forest landscapes. Our findings support the promotion of partial cut harvest as an effective strategy to achieve species and habitat conservation goals.

Dynamics of coarse woody debris and decomposition rates in an old-growth forest in lower tropical China

2010 ◽  
Vol 259 (8) ◽  
pp. 1666-1672 ◽  
Author(s):  
Fang-Fang Yang ◽  
Yue-Lin Li ◽  
Guo-Yi Zhou ◽  
K.O. Wenigmann ◽  
De-Qiang Zhang ◽  
...  
Keyword(s):  
Coarse Woody Debris ◽  
Woody Debris ◽  
Decomposition Rates ◽  
Old Growth ◽  
Old Growth Forest ◽  
Tropical China

Volumosina, a new Nearctic genus for the rare old-growth forest fly Herniosina voluminosa Marshall (Diptera: Sphaeroceridae)

2017 ◽  
Vol 149 (4) ◽  
pp. 444-460 ◽  
Author(s):  
Jindřich Roháček ◽  
Stephen A. Marshall
Keyword(s):  
Natural History ◽  
New Genus ◽  
Woody Debris ◽  
Morphological Characters ◽  
Large Woody Debris ◽  
New Combination ◽  
Old Growth ◽  
History Data ◽  
Old Growth Forest

AbstractVolumosinanew genus (Diptera: Sphaeroceridae: Limosininae) is described to accomodate the enigmatic Nearctic species Herniosina voluminosa Marshall, 1987 and its relationships are discussed. Based on morphological characters Volumosina is treated as part of the Limosina genus group along with Apteromyia Vimmer, 1929, Gigalimosina Roháček, 1983, Herniosina Roháček, 1983, and Limosina Macquart, 1835 but its position within the group remains unresolved. Volumosina voluminosa (Marshall, 1987) new combination is recorded from Canada and redescribed with new distributional and natural history data suggesting that it is an old-growth specialist associated with large woody debris. The gigantism of the male aedeagal complex of V. voluminosa is discussed.

scholarly journals Riparian old-growth forests provide critical nesting and foraging habitat for Blakiston's fish owl Bubo blakistoni in Russia

Oryx ◽  
2013 ◽  
Vol 47 (4) ◽  
pp. 553-560 ◽  
Author(s):  
Jonathan C. Slaght ◽  
Sergei G. Surmach ◽  
R.J. Gutiérrez
Keyword(s):  
Woody Debris ◽  
Habitat Characteristics ◽  
Suitable Habitat ◽  
Home Ranges ◽  
Foraging Habitat ◽  
Old Growth ◽  
Nest Sites ◽  
Old Growth Forest ◽  
Large Trees ◽  
Old Growth Forests

AbstractConservation efforts for Blakiston's fish owl Bubo blakistoni in Russia are limited, partly because habitat use by these rare owls is poorly known. We therefore studied nesting and foraging habitat characteristics of Blakiston's fish owls in Primorye, Russia. We sampled habitat at 14 nest sites, 12 nest stand sites and 13 random sites; we also sampled rivers within 14 fish owl home ranges across our 20,213 km2 study area. We found that large old trees and riparian old-growth forest were the primary characteristics of nest and foraging sites, respectively. Large trees were probably used as nest sites because they have cavities large enough to accommodate these birds. Big trees are also important because they are primary sources of large woody debris in rivers, which enhances suitable habitat for salmon, the owl's primary prey. Based on habitat characteristics, nest sites were correctly distinguished from random sites 74% (Kappa = 0.48) of the time, nest stands from random sites 56% (Kappa = 0.12) of the time, and used sites from available foraging sites 68% (Kappa = 0.36) of the time. The management and conservation of old-growth forests is essential for sustaining this species because they are central to the owls' nesting and foraging behaviour. Moreover, conservation of these forests sustains habitat for many other species.

Effect of small-scale forest management on fungivorous Coleoptera in old-growth forest fragments in southeastern Ontario, Canada

2007 ◽  
Vol 139 (1) ◽  
pp. 118-130 ◽  
Author(s):  
Rebecca M. Zeran ◽  
Robert S. Anderson ◽  
Terry A. Wheeler
Keyword(s):  
Forest Management ◽  
Coarse Woody Debris ◽  
Woody Debris ◽  
Hardwood Forests ◽  
Small Scale ◽  
Forest Fragments ◽  
Forest Types ◽  
Old Growth ◽  
Old Growth Forest ◽  
Species Analysis

AbstractFungivorous Coleoptera were sampled from old-growth and managed (selectively logged in 1999) hemlock–hardwood forests in southeastern Ontario to examine the effect of small-scale forest management on fungivore diversity in forest fragments. Sampling using flight-intercept traps and trunk-window traps for 22 weeks in 2003 yielded 11 888 beetles representing 73 species in 11 target families (Anthribidae, Cerylonidae, Endomychidae, Erotylidae, Leiodidae, Mycetophagidae, Scaphidiidae, Sphindidae, Tenebrionidae, Trogossitidae, and Zopheridae). The leiodid subfamily Leiodinae was the dominant taxon (10 386 individuals, 38 species). While old-growth stands had no recent logging and had higher volumes of coarse woody debris, species diversity and composition of fungivorous Coleoptera were similar between forest types, suggesting that the stand differences measured (recent logging history, volume of coarse woody debris) did not have a significant effect on beetle diversity in this study. Indicator species analysis showed that Triplax macra LeConte (Erotylidae) was strongly associated with old-growth stands, while Anisotoma blanchardi (Horn), Anogdus obsoletus (Melsheimer), Agathidium sp. 1 (Leiodidae), and Mycetina perpulchra (Newman) (Endomychidae) were associated with managed stands. The lack of difference observed between stand types may be related to the small size of the forest fragments or the relatively small scale of the disturbance.

Riparian bryophyte vegetation in the Cascade mountain range, Northwest U.S.A.: patterns at different spatial scales

1997 ◽  
Vol 75 (5) ◽  
pp. 744-761 ◽  
Author(s):  
Bengt Gunnar Jonsson
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Environmental Gradients ◽  
Woody Debris ◽  
Spatial Scales ◽  
Regional Distribution ◽  
Mountain Range ◽  
Old Growth ◽  
Old Growth Forest ◽  
Stream Size

Riparian forests are productive and species rich ecosystems where the vegetation is structured by sharp environmental gradients. The study describes community patterns of bryophytes in stream-side forests, relates these patterns to major environmental gradients, and compares within-site factors with site level variables. Samples were collected from 360 plots 2 × 4 m in size distributed among 42 sites in old-growth Pseudotsuga–Tsuga forests. The sites ranged from 420 to 1250 m asl and stream size from 1st to 5th order streams. There were significant changes in species richness and composition along several environmental gradients. Richness within sites varied among different geomorphic surfaces with the highest number of species on areas periodically flooded. Richness was also higher in plots with high abundance of woody debris. No site level factors influenced richness at the sample plot level, while the highest species number at the site level was for large streams. The main gradients in the species composition within sites were changes with increasing distance from the stream and amount of woody debris. Both elevation and stream size significantly influenced species composition. The complex set of factors that influenced species richness and composition implies that management of riparian vegetation must be based on both coarse scale considerations such as regional distribution of different stream types and fine scale factors such as spatial availability of different substrate types. Key words: old-growth forest; CCA analysis; fluvial disturbance; bryophytes; elevation effects; coarse woody debris.

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