Comparison of plantations and naturally regenerated clearcuts in the Acadian Forest: forest floor bryophyte community and habitat features

2002 ◽  
Vol 80 (1) ◽  
pp. 21-33 ◽  
Author(s):  
Amy L Ross-Davis ◽  
Katherine A Frego

To address concern for loss of bryophyte biodiversity within managed forests, we compared community composition and environmental characteristics among three disturbance regimes: (i) naturally regenerated clear-cut forests, (ii) cutover spruce plantations (established on clear-cut forest land), and (iii) afforested field spruce plantations (established on agricultural fields) across a range of ages (19–102 years) in the Acadian Forest region of New Brunswick, Canada. Abundances of all forest floor bryophyte species, available substrates, microtopographical features, and tree canopy were measured as percent cover (1 m2) in 26 stands: 12 naturally regenerated clear-cut forests, eight cutover plantations, and six afforested field plantations. Multivariate analyses indicated that both bryophyte community composition and associated environment differed significantly across disturbance regimes, with no strong trends related to time since clearing (i.e., stand age). Spruce plantations were characterized by low substrate diversity and microtopographic and canopy homogeneity. Both plantation types had lower bryophyte species richness, evenness, and diversity (H') relative to naturally regenerated clear-cut forests; cutover plantations had the highest total bryophyte cover. The bryophyte community of plantations was composed of a subset of species found within naturally regenerated clear-cut forests: many liverworts and epixylic mosses were absent, with fewer pioneer species and more perennial stayers (equivalent to K-strategists) than expected.Key words: bryophyte, disturbance regime, substrate, canopy, microtopography, plantation.

2004 ◽  
Vol 34 (5) ◽  
pp. 998-1006 ◽  
Author(s):  
Zoë Lindo ◽  
Suzanne Visser

The effects of partial and clear-cut harvesting on abundance and community composition of forest floor microarthropods and oribatid mites were investigated in conifer and deciduous stands of the mixedwood boreal forest. Soil samples from clearcuts, strip-cut corridors in a partial cut, green-tree retention patches in a partial cut, and uncut control sites were collected 2.5 years after harvest and microarthropods were extracted, enumerated, and identified. Densities of microarthropod suborders were lower in the strip-cut corridors of the deciduous stands and significantly lower in the suborder Oribatida (oribatid mites). Changes in microarthropod community composition, decreased relative abundance of prostigmatid mites, and increased relative abundance of mesostigmatid mites were observed in corridor and clear-cut treatments. Lowered abundances and changes in community composition are likely due to compaction of the forest floor during harvesting. Selected oribatid mite species showed significantly lower abundances in clearcuts than in uncut sites, but diversity indices for oribatid mites were generally not significantly different between uncut sites and clearcuts. Changes in oribatid mite communities following harvesting were thus more quantitative (absolute abundance) than qualitative (diversity, composition), and as a result, use of oribatid mites as biological indicators of disturbance is limited because of the lack of changes in species composition.


1992 ◽  
Vol 24 (2) ◽  
pp. 165-180
Author(s):  
M. Hyvärinen ◽  
P. Halonen ◽  
M. Kauppi

Abstract The epiphytic lichen vegetation on the trunks of Pinus sylvestris and Picea abies was studied and analysed by canonical correspondence analysis in relation to a number of environmental variables. The distribution and abundance of epiphytic lichen species proved to be dependent on the age of the stand, showing divergent responses in relation to phorophyte species and environmental variables such as acidity of the bark and vertical location on the trunk. The importance of stand age in the pattern of community variation is concluded to be an outcome of interaction between changes in the structure of the tree canopy, microclimate and properties of the bark. The responses of single lichen species to changes in the environment seem to vary considerably, indicating differences in competitive ability and ecological strategy between the species.


2008 ◽  
Vol 140 (4) ◽  
pp. 453-474 ◽  
Author(s):  
David W. Langor ◽  
H.E. James Hammond ◽  
John R. Spence ◽  
Joshua Jacobs ◽  
Tyler P. Cobb

AbstractSaproxylic insect assemblages inhabiting dead wood in Canadian forests are highly diverse and variable but quite poorly understood. Adequate assessment of these assemblages poses significant challenges with respect to sampling, taxonomy, and analysis. Their assessment is nonetheless critical to attaining the broad goals of sustainable forest management because such species are disproportionately threatened elsewhere by the reductions in dead wood generally associated with commercial exploitation of northern forests. The composition of the saproxylic fauna is influenced by many factors, including tree species, degree of decay, stand age, and cause of tree death. Wildfire and forest harvesting have differential impacts on saproxylic insect assemblages and on their recovery in postdisturbance stands. Exploration of saproxylic insect responses to variable retention harvesting and experimental burns is contributing to the development of prescriptions for conserving saproxylic insects in boreal forests. Understanding of processes that determine diversity patterns and responses of saproxylic insects would benefit from increased attention to natural history. Such work should aim to provide a habitat-classification system for dead wood to better identify habitats (and associated species) at risk as a result of forest management. This tool could also be used to improve strategies to better maintain saproxylic organisms and their central nutrient-cycling functions in managed forests.


1992 ◽  
Vol 22 (8) ◽  
pp. 1089-1093 ◽  
Author(s):  
R. Trowbridge ◽  
F.B. Holl

An overdense lodgepole pine (Pinuscontorta Dougl. ex Loud.) stand was knocked down and the site was prepared by broadcast burn, windrow burn, or mechanical forest floor removal. Inoculated alsike clover (Trifoliumhybridum L.) was seeded at 0, 10, 20, and 30 kg/ha for the three different site preparation treatments to determine the effects of (i) site preparation on infection and effectiveness of the clover–Rhizobium symbiosis and clover percent cover and (ii) the clover–Rhizobium N2-fixing symbiosis on survival, early growth, and foliar nitrogen concentration of lodgepole pine seedlings. The N2-fixing symbiosis established well in all treatments. Clover percent cover increased with increasing rate of seeding, although by relatively few percent in the clover seeded plots. Broadcast burning, windrow burning, and mechanical forest floor removal did not affect the establishment of the N2-fixing symbiosis or clover percent cover. Lodgepole pine survival was not affected by the seeding treatments in any year, nor were height measurements during the first three growing seasons. Seedling height was slightly less in clover-seeded plots compared with controls in the fourth growing season. Lodgepole pine seedlings on clover-seeded plots had decreased diameter growth compared with controls during the first three growing seasons, but incremental diameter growth no longer showed this effect by the fourth growing season. Needle mass (g/100 needles) was less in clover-seeded plots at the end of the second growing season, but this effect was reversed by the fourth growing season, when both needle mass and foliar nitrogen concentration in lodgepole pine foliage were greater in clover-seeded plots.


2011 ◽  
Vol 41 (8) ◽  
pp. 1687-1697 ◽  
Author(s):  
Lee Jacobs ◽  
Jeff E. Houlahan

Here, we examine the effects of adjacent land use in a managed forest on pond-breeding amphibian species richness and community composition at 34 New Brunswick, Canada, ponds. Amphibian species richness was negatively correlated with the proportion of roads, precommercial thinning, and hardwood forest and positively correlated with the proportion of wetlands in adjacent lands. These land-use effects peak at 180 m from the ponds. Road density was negatively correlated with Lithobates catesbeiana and Lithobates septentrionalis presence. Precommercial thinning was negatively correlated with Ambystoma spp. presence and positively correlated with Anaxyrus americanus presence. Wetlands were positively correlated with L. septentrionalis and Notopthalamus viridescens presence. Correlations were also found between water table height and A. americanus, Lithobates palustris , and Ambystoma spp. presence. In addition, L. catesbeiana and N. viridescens presence–absence was positively correlated with the proportion of mature and overmature forest on the landscape (at scales of 500 and 1000 m, respectively). Lastly, the proportion of regenerating and sapling forest on the landscape was negatively correlated with L. palustris presence–absence but, by contrast, was positively correlated with A. americanus. These results suggest that the effects of adjacent land use may significantly impact amphibian populations in managed eastern Canadian forests.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2213 ◽  
Author(s):  
Andrea S. Jerabek ◽  
Kara R. Wall ◽  
Christopher D. Stallings

Biofouling of experimental cages and other field apparatuses can be problematic for scientists and has traditionally been addressed using frequent manual removal (e.g., scraping, scrubbing). Recent environmental restrictions and legislative changes have driven the development of less hazardous antifouling products, making antifouling paint a potential alternative option to manual removal. Consequently, the viability of using these newly developed products as a replacement for the manual cleaning of exclusion cages was experimentally investigated. There were six treatments tested, comprising three with settlement tiles in experimental cages coated with antifouling paint, two with settlement tiles in unpainted experimental cages, and one cage-free suspended tile. The three antifouling treatments comprised two reduced-copper paints (21% Cu2O and 40% Cu2O) and one copper-free, Econea™-based paint (labeled “ecofriendly”). Antifouling paints were assessed for performance of preventing fouling of the cages and whether they elicited local effects on settlement tiles contained within them. All three paints performed well to reduce fouling of the cages during the initial six weeks of the experiment, but the efficacy of “ecofriendly” paint began to decrease during an extended deployment that lasted 14 weeks. The macro-community composition, biomass, and percent cover of settled organism on tiles within cages treated with copper-based paints (21% and 40% concentrations) were indistinguishable from tiles within the manually scrubbed cages. In contrast, settlement to tiles from the “ecofriendly” treatment was different in composition of macro-community and lower in biomass, suggesting the presence of local effects and therefore rendering it unsuitable for use in settlement experiments. The results of this study suggest that reduced-copper paints have the potential to serve as an alternative to manual maintenance, which may be useful for deployments in locations that are difficult to access on a frequent schedule.


Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1542
Author(s):  
Nadezhda V. Genikova ◽  
Viktor N. Mamontov ◽  
Alexander M. Kryshen ◽  
Vladimir A. Kharitonov ◽  
Sergey A. Moshnikov ◽  
...  

Bilberry spruce forests are the most widespread forest type in the European boreal zone. Limiting the clear-cuttings size leads to fragmentation of forest cover and the appearance of large areas of ecotone complexes, composed of forest (F), a transition from forest to the cut-over site under tree canopy (FE), a transition from forest to the cut-over site beyond tree canopy (CE), and the actual clear-cut site (C). Natural regeneration of woody species (spruce, birch, rowan) in the bilberry spruce stand—clear-cut ecotone complex was studied during the first decade after logging. The effects produced by the time since cutting, forest edge aspect, and the ground cover on the emergence and growth of trees and shrubs under forest canopy and openly in the clear-cut were investigated. Estimating the amount and size of different species in the regeneration showed FE and CE width to be 8 m—roughly half the height of first-story trees. Typical forest conditions (F) feature a relatively small amount of regenerating spruce and birch. The most favorable conditions for natural regeneration of spruce in the clear-cut—mature bilberry spruce stand ecotone are at the forest edge in areas of transition both towards the forest and towards the clear-cut (FE and CE). Clear-cut areas farther from the forest edge (C) offer an advantage to regenerating birch, which grows densely and actively in this area.


Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1562
Author(s):  
Iveta Varnagirytė-Kabašinskienė ◽  
Povilas Žemaitis ◽  
Kęstutis Armolaitis ◽  
Vidas Stakėnas ◽  
Gintautas Urbaitis

In the context of the specificity of soil organic carbon (SOC) storage in afforested land, nutrient-poor Arenosols and nutrient-rich Luvisols after afforestation with coniferous and deciduous tree species were studied in comparison to the same soils of croplands and grasslands. This study analysed the changes in SOC stock up to 30 years after afforestation of agricultural land in Lithuania, representing the cool temperate moist climate region of Europe. The SOC stocks were evaluated by applying the paired-site design. The mean mass and SOC stocks of the forest floor in afforested Arenosols increased more than in Luvisols. Almost twice as much forest floor mass was observed in coniferous than in deciduous stands 2–3 decades after afforestation. The mean bulk density of fine (<2 mm) soil in the 0–30 cm mineral topsoil layer of croplands was higher than in afforested sites and grasslands. The clear decreasing trend in mean bulk density due to forest stand age with the lowest values in the 21–30-year-old stands was found in afforested Luvisols. In contrast, the SOC concentrations in the 0–30 cm mineral topsoil layer, especially in Luvisols afforested with coniferous species, showed an increasing trend due to the influence of stand age. The mean SOC values in the 0–30 cm mineral topsoil layer of Arenosols and Luvisols during the 30 years after afforestation did not significantly differ from the adjacent croplands or grasslands. The mean SOC stock slightly increased with the forest stand age in Luvisols; however, the highest mean SOC stock was detected in the grasslands. In the Arenosols, there was higher SOC accumulation in the forest floor with increasing stand age than in the Luvisols, while the proportion of SOC stocks in mineral topsoil layers was similar and more comparable to grasslands. These findings suggest encouragement of afforestation of former agricultural land under the current climate and soil characteristics in the region, but the conversion of perennial grasslands to forest land should be done with caution.


2005 ◽  
Vol 2 (4) ◽  
pp. 1127-1157 ◽  
Author(s):  
K. Butterbach-Bahl ◽  
U. Berger ◽  
N. Brüggemann ◽  
J. Duyzer

Abstract. This study provides for the first time data on the stratification of NO and N2O production with soil depth under aerobic and anaerobic incubation conditions for different temperate forest sites in Germany (spruce, beech, clear-cut) and the Netherlands (Douglas fir). Results show that the NO and N2O production activity is highest in the forest floor and decreases exponentially with increasing soil depth. Under anaerobic incubation conditions NO and N2O production was in all soil layers up to 2-3 orders of magnitude higher then under aerobic incubation conditions. Furthermore, significant differences between sites could be demonstrated with respect to the magnitude or predominance of NO and N2O production. These were driven by stand properties (beech or spruce) or management (clear-cut versus control). With regard to CH4 the most striking result was the lack of CH4 uptake activity in soil samples taken from the Dutch Douglas fir site at Speulderbos, which is most likely a consequence of chronically high rates of atmospheric N deposition. In addition, we could also demonstrate that CH4 fluxes at the soil surface are obviously the result of simultaneously occurring uptake and production processes, since even under aerobic conditions a net production of CH4 in forest floor samples was found. The provided dataset will be very useful for the development and testing of process oriented models, since for the first time activity data stratified for several soil layers for N2O, NO, and CH4 production/oxidation activity for forest soils are provided.


Forests ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 759
Author(s):  
Hongxing Wang ◽  
Dongsheng Chen ◽  
Xiaomei Sun

Increased demand for forest-derived biomass has led to more intensive harvesting practices. However, the export of large nutrient quantities with the harvested biomass may lead to the depletion of soil nutrients. Therefore, improved knowledge concerning macronutrient allocation (N, P, K, Ca, and Mg) to different components in forests along age sequences is crucial for their sustainable management. In this study, we quantified nutrient allocation to different ecosystem components, including trees, understorey, forest floor, and different soil depths within a chronosequence (6-, 15-, 23-, and 35-year-old) of larch plantations in China. We then assessed the danger of significant nutrient losses from whole tree harvesting (WTH). Nutrient amounts in trees increased with stand age due to an increase in biomass. Stems accounted for 59%–72% of tree biomass and contained 40%–50% of total tree nutrients in the 15- to 35-year-old stands. The forest floor’s nutrient quantities increased from the 6- to 23-year-old stands and then decreased in the 35-year-old plantations. Conversely, most soil indicators initially declined from 15- to 23-year-old stands and then increased in the 35-year-old stand. The total nutrient stocks were greatest in the soil (0–40 cm), which accounted for about 93%–99% of total nutrients in the larch ecosystem. These data indicate that WTH causes nutrient losses about 2.0–2.5 times higher than stem-only harvesting, when thinning 15- or clear-cut harvesting 23- and 35-year-old stands. However, nutrient losses by WTH have little effect on the soil nutrient pools. Prolonging the crop cycle of larch plantations may be beneficial to improve nutrient return through litterfall and allow available soil nutrients to recover.


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