Experimental manipulation of habitat structures in intensively managed spruce plantations to increase their value for biodiversity conservation

Six intensively managed white spruce (Picea glauca (Moench) Voss) plantations located in three general landscape contexts (plantation dominated, hardwood dominated, and mixed hardwood and plantation) in northern New Brunswick underwent alternative commercial thinning (CT) treatments: 1) an unthinned control; and three 40% basal area CT removals, with 2) slash and tops remaining on site (status quo CT), 3) branches and tops extracted from the site (biomass removal CT), and 4) clumps of unthinned trees left, and one-half girdled to create snags (enhanced structure CT). We examined responses of taxa that have a clear connection to deadwood and thinning response: beetles and bird species that are directly dependent upon deadwood, ground vegetation species sensitive to disturbance, and small mammals that have been observed to have low density in planted stands. Results three years post-thinning showed that crown width and tree growth responded positively to CT, and herbaceous vegetation diverged from reference stands and unthinned treatments with CT, but greatest compositional change was associated with biomass removal CT. Beetles responded positively to CT, small mammal species responded both positively (red-backed voles) and negatively (woodland jumping mice) to CT, but areas dominated by plantations had negative effects on voles. Effects of CT on songbirds were unclear and their quantification would require larger treated blocks, but maintenance of habitat at the landscape level is essential for the conservation of bird species that require deadwood. The experimental biomass removal CT was least similar to both unthinned and older unmanaged stands, and may therefore be detrimental to biodiversity conservation efforts. These results are only the initial three years after treatment but set the study up to permit a long-term legacy of determining long-term responses of taxa over stand development.

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Do biomass removal and structure-enhancing treatments influence deadwood characteristics following commercial thinning in spruce plantations in New Brunswick, Canada?

Canadian Journal of Forest Research ◽

10.1139/cjfr-2014-0381 ◽

2015 ◽

Vol 45 (10) ◽

pp. 1407-1418 ◽

Cited By ~ 5

Author(s):

Kwadwo Omari ◽

David A. MacLean

Keyword(s):

New Brunswick ◽

Picea Glauca ◽

Woody Debris ◽

Basal Area ◽

Status Quo ◽

Commercial Thinning ◽

Dead Trees ◽

Biomass Removal ◽

The Status ◽

Intensively Managed

Effects of commercial thinning on downed coarse woody debris (CWD) and standing dead trees (snags) were examined in six intensively managed 22- to 30-year-old white spruce (Picea glauca (Moench) Voss) plantations in northern New Brunswick, Canada. Four alternative treatments were applied: (i) an unthinned control and three commercial thinning 40% basal area removals, with (ii) slash and tops remaining on the site (status quo), (iii) most of the branches and tops extracted from the site (biomass removal), and (iv) clumps of unthinned trees left, with one-half of the trees in each clump girdled to create snags (enhanced structure). Three years after thinning, CWD volume increased by 14%–27% in the status quo and enhanced structure treatments, by 6% in the biomass removal treatment, and by 0.1% in the unthinned treatment. Mean snag volume changed little, i.e., less than 1 m3·ha−1 among treatments, and stumps of thinned trees were 4.6–4.9 m3·ha−1. The girdled trees added 0.7 m3·ha−1 of snags, and 1.3 m3·ha−1 is expected to be added from girdling the remaining live trees in the unthinned clumps in 2016. The girdled trees and future to-be-girdled trees added up to 50% of the new deadwood in the enhanced structure treatments, but thinning treatments did not significantly affect total deadwood. The results indicate that commercial thinning produced fine debris but had little effect on overall deadwood amount. Girdling trees during commercial thinning, at the intensity used in this study, is unlikely to produce sufficient snags. Leaving islands and clumps during harvest before plantation establishment would be a more effective way of adding structure.

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Uneven-aged silviculture of Scots pine in Bohemia and Central Spain: comparison study of stand reaction to transition and long-term selection management

Journal of Forest Science ◽

10.17221/147/2019-jfs ◽

2020 ◽

Vol 66 (No. 1) ◽

pp. 22-35 ◽

Cited By ~ 1

Author(s):

Josef Gallo ◽

Lukáš Bílek ◽

Václav Šimůnek ◽

Sonia Roig ◽

José Alfredo Bravo Fernández

Keyword(s):

Scots Pine ◽

Sustainable Forest Management ◽

Environmental Changes ◽

Basal Area ◽

Diversity Indices ◽

Mountain Range ◽

Central Spain ◽

Ecological Requirements ◽

Intensively Managed

The achievement of sustainable forest management requires the incorporation of ongoing environmental changes into long-term planning. Moreover, in time of climatic change and changing company demands, importance of Scots pine (Pinus sylvestris L.) is still increasing at the expense of other tree species due to its low ecological requirements. The aim of the study was to compare the structure and production of Scots pine stands managed under different silvicultural systems on four research plots, assess the structural and diversity indices, and analyse the increment structure using tree-ring dating in the Czech Republic and Spain. Area of study was Western Bohemian and Guadarrama Mountain range in Central Spain. The results indicate that stand volume on the investigated plots ranged from 231 to 441 m3∙ha–1 with tree density 276–996 trees∙ha–1. Intensively managed (uneven-aged) permanent research plots showed increased growth on basal area. The difference was evident also for older trees. The transition to uneven-aged forest does not negatively influence stocking and wood production and provide higher benefits for diversity and structural complexity in comparison to regular stands.

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Woodland mouse and vole response to increased structural diversity following midrotation commercial thinning in spruce plantations

Canadian Journal of Forest Research ◽

10.1139/cjfr-2014-0472 ◽

2015 ◽

Vol 45 (8) ◽

pp. 1121-1131 ◽

Cited By ~ 9

Author(s):

Evan C. Dracup ◽

Daniel M. Keppie ◽

Graham J. Forbes

Keyword(s):

Picea Glauca ◽

Structural Changes ◽

Woody Debris ◽

Basal Area ◽

Structural Diversity ◽

Understory Vegetation ◽

Deer Mice ◽

Mammal Species ◽

Commercial Thinning ◽

Debris Removal

We assessed whether commercially thinning (CT) spruce (Picea spp.) plantations (40% basal area removal) can cause structural changes in fine woody debris (FWD) and understory vegetation to improve habitat quality for small rodents in northwestern New Brunswick, Canada. We created three contrasting environments (FWD rich – understory vegetation rich, FWD poor – understory vegetation rich, and FWD poor – understory vegetation poor) by establishing CT with debris retention (merchantable trunk removal), CT with all debris removed (full tree removal), and non-CT (plantation without CT) in six midrotation white spruce (Picea glauca (Moench) Voss) plantations. We live-trapped small mammals in each plantation during spring and summer of 2011 and 2012 and estimated animal density and survival with capture–recapture models. Southern red-backed vole (Myodes gapperi (Vigors, 1830)) density was two to three times greater in CT with debris retention than in either non-CT or CT with debris removal, and their survival rate was twice that in CT with debris removal. Woodland jumping mouse (Napaeozapus insignis (Miller, 1891)) density was two to five times greater in non-CT than in either CT treatment. Deer mice (Peromyscus maniculatus (Wagner, 1845)) did not show any treatment effect. Productivity and demographics were not affected by CT treatment for any species. We found evidence that midrotation spruce plantations are used differently by small mammal species based on stand condition and recommend that managers maintain plantations in CT and non-CT states.

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Modeling growth and yield of loblolly pinestands under intensive management

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2015000800009 ◽

2015 ◽

Vol 50 (8) ◽

pp. 707-717 ◽

Cited By ~ 3

Author(s):

Antonio Carlos Ferraz Filho ◽

José Roberto Soares Scolforo ◽

Antonio Donizette de Oliveira ◽

José Márcio de Mello

Keyword(s):

Model Validation ◽

Loblolly Pine ◽

Basal Area ◽

Growth And Yield ◽

Diameter Class ◽

Commercial Thinning ◽

Volume Yield ◽

Intensively Managed ◽

Parameter Values ◽

Validation Scheme

Abstract:The objective of this work was to develop and validate a prognosis system for volume yield and basal area of intensively managed loblolly pine (Pinus taeda) stands, using stand and diameter class models compatible in basal area estimates. The data used in the study were obtained from plantations located in northern Uruguay. For model validation without data loss, a three-phase validation scheme was applied: first, the equations were fitted without the validation database; then, model validation was carried out; and, finally, the database was regrouped to recalibrate the parameter values. After the validation and final parameterization of the models, a simulation of the first commercial thinning was carried out. The developed prognosis system was precise and accurate in estimating basal area production per hectare or per diameter classes. There was compatibility in basal area estimates between diameter class and whole stand models, with a mean difference of -0.01 m2ha-1. The validation scheme applied is logic and consistent, since information on the accuracy and precision of the models is obtained without the loss of any information in the estimation of the models' parameters.

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Genotypic variation and recovery of Populus tremuloides from biomass removal and compaction in northern Wisconsin, USA

Canadian Journal of Forest Research ◽

10.1139/x04-147 ◽

2005 ◽

Vol 35 (1) ◽

pp. 221-228 ◽

Cited By ~ 2

Author(s):

J G Bockheim ◽

H Park ◽

J Gallagher

Keyword(s):

Populus Tremuloides ◽

Forest Floor ◽

Genotypic Variation ◽

Basal Area ◽

Site Index ◽

Height Growth ◽

Site Quality ◽

Long Term Effects ◽

Biomass Removal

This study was initiated in 1990 to determine the effects of simulated logging practices on long-term productivity of trembling aspen (Populus tremuloides Michx.). Treatments included three levels of biomass removal (entire aboveground woody biomass, control; control + coarse woody detritus, LS; and LS + forest floor, FF) and two levels of compaction (light compaction on winter skid roads, TRA; heavy simulated compaction with FF, COM). The study was conducted on a Typic Haplorthod and a Haplic Glossudalf of medium site quality (site index50 years = 21 and 23 m, respectively) on the Brule State Forest. Twelve years after treatment, the following results were noted: (1) there were no significant differences in aspen height growth among treatments at either site except for lower stocking, height, diameter, and basal area on heavily compacted plots (COM, forest floor removed before compaction) at the clay site; (2) there was considerable genotypic variation in aspen height growth; and (3) recovery of physical properties, as reflected by bulk density, occurred within 12 years of treatment but was not manifested by improved aspen growth. These results suggest that concern over long-term effects of intensified biomass removal and soil compaction should be matched by a concern over protection of the aspen gene pool in the upper Great Lakes region.

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Effects of clear-cutting and wildfires on succession of ground beetle (Coleoptera: Carabidae) assemblages on the east slopes of the Rocky Mountains

ARPHA Conference Abstracts ◽

10.3897/aca.2.e39118 ◽

2019 ◽

Vol 2 ◽

Author(s):

Vincent Del Bel Belluz ◽

David Langor ◽

Jari Niemelä ◽

John Spence

Keyword(s):

Ground Beetle ◽

Mineral Soil ◽

Basal Area ◽

Species Assemblages ◽

Ground Vegetation ◽

Clear Cut ◽

Clear Cutting ◽

Beetle Assemblages ◽

Trees And Shrubs

We studied how carabid beetle assemblages in lodgepole pine stands have responded after clear-cut harvest and wildfires on an actively managed landscape ~20 km south of Hinton, Alberta, Canada. The work builds on and expands a previous study (Niemela et al. 1993) conducted 23-24 years earlier in many of the same stands sampled in the current study. Carabid species assemblages are compared along a chronosequence of stands ranging in age from 12 to 53 years after clear-cutting. Recovery of carabid assemblages toward pre-harvest structure in regenerating stands, as reflected in the 2013-14 data, appears to have progressed more rapidly than in equivalently aged stands from the earlier study. In addition, carabid species assemblages differed significantly between clear-cut and burned stands of comparable age in 2013-14, with assemblages of burned stands being more similar to the pre-harvest structure than in clear-cut stands. Ground vegetation, mineral soil cover and basal area of trees and shrubs were significantly correlated with structure of carabid species assemblages in young and old regenerating stands, suggesting that environmental and plant successional gradients drive patterns in carabid assemblages. However, assemblage differences between older burned and clear-cut stands indicate that the type of disturbance influences long-term carabid recovery. Relationships between these findings and issues related to conservation of biodiversity and climate change are discussed.

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Yield Comparisons from Even-Aged and Uneven-Aged Loblolly-Shortleaf Pine Stands

Southern Journal of Applied Forestry ◽

10.1093/sjaf/12.2.107 ◽

1988 ◽

Vol 12 (2) ◽

pp. 107-114 ◽

Cited By ~ 12

Author(s):

James M. Guldin ◽

James B. Baker

Keyword(s):

Pinus Taeda ◽

Coastal Plain ◽

Basal Area ◽

Selection Method ◽

Shortleaf Pine ◽

Large Size ◽

Intensively Managed ◽

Pinus Taeda L ◽

Long Term Studies

Abstract Empirical yields for a 36-year management period are presented for seven long-term studies on similar sites in loblolly-shortleaf pine (Pinus taeda L.-P. echinata Mill.) stands on the upper southern coastal plain of southern Arkansas and northern Louisiana. Total merchantable cubic-foot yields are highest for conventionally managed even-aged plantations; sawtimber cubic-foot yields are highest for intensively managed even-aged plantations and intensively managed uneven-aged stands. However, uneven-aged stands have higher board-foot sawtimber yields than the most productive even-aged stands, particularly in comparisons using the Doyle log rule. It is hypothesized that the even-aged plantations have higher cubic-foot yields because they are more fully stocked with trees of merchantable size. Conversely, the uneven-aged stands have higher board-foot yields because of the greater proportion and continuous supply of sawtimber basal area, especially in stems of large size, which can be developed using the uneven-aged selection method. South J. Appl. For. 12(5):107-114

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Domain randomization-enhanced deep learning models for bird detection

Scientific Reports ◽

10.1038/s41598-020-80101-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Xin Mao ◽

Jun Kang Chow ◽

Pin Siang Tan ◽

Kuan-fu Liu ◽

Jimmy Wu ◽

...

Keyword(s):

Deep Learning ◽

Continuous Monitoring ◽

Bird Species ◽

Training Data ◽

Learning Models ◽

Fine Grained ◽

Bird Detection ◽

Relationship Of ◽

The Relationship

AbstractAutomatic bird detection in ornithological analyses is limited by the accuracy of existing models, due to the lack of training data and the difficulties in extracting the fine-grained features required to distinguish bird species. Here we apply the domain randomization strategy to enhance the accuracy of the deep learning models in bird detection. Trained with virtual birds of sufficient variations in different environments, the model tends to focus on the fine-grained features of birds and achieves higher accuracies. Based on the 100 terabytes of 2-month continuous monitoring data of egrets, our results cover the findings using conventional manual observations, e.g., vertical stratification of egrets according to body size, and also open up opportunities of long-term bird surveys requiring intensive monitoring that is impractical using conventional methods, e.g., the weather influences on egrets, and the relationship of the migration schedules between the great egrets and little egrets.

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Nest cameras do not affect nest survival in a meadow-nesting shorebird

Bird Conservation International ◽

10.1017/s0959270920000659 ◽

2020 ◽

pp. 1-10

Author(s):

VOLKER SALEWSKI ◽

LUIS SCHMIDT

Keyword(s):

Nest Survival ◽

Bird Species ◽

Conservation Strategies ◽

Survival Models ◽

Northern Germany ◽

Term Study ◽

Long Term Study ◽

Limosa Limosa ◽

Study Sites

Summary Identifying the fate of birds’ nests and the causes of breeding failure is often crucial for the development of conservation strategies for threatened species. However, collecting these data by repeatedly visiting nests might itself contribute to nest failure or bias. To solve this dilemma, automatic cameras have increasingly been used as a time-efficient means for nest monitoring. Here, we consider whether the use of cameras itself may influence hatching success of nests of the Black-tailed Godwit Limosa limosa at two long-term study sites in northern Germany. Annually between 2013 and 2019, cameras were used to monitor godwit nests. In 2014 and 2019, nests were randomly equipped with cameras or not, and nest survival checked independently of the cameras. Nest-survival models indicated that survival probabilities varied between years, sites and with time of the season, but were unaffected by the presence of cameras. Even though predation is the main cause of hatching failure in our study system, we conclude that predators did not learn to associate cameras with food either when the cameras were initially installed or after they had been used for several years. Cameras were thus an effective and non-deleterious tool to collect data for conservation in this case. As other bird species may react differently to cameras at their nests, and as other sets of predators may differ in their ability to associate cameras with food, the effect of cameras on breeding success should be carefully monitored when they are used in a new study system.

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Long-term stress level in a small mammal species undergoing range expansion

Mammalia ◽

10.1515/mammalia-2020-0041 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Adrien André ◽

Johan Michaux ◽

Jorge Gaitan ◽

Virginie Millien

Keyword(s):

Stress Level ◽

Species Distribution ◽

Small Mammal ◽

Range Expansion ◽

Mammal Species ◽

Distribution Ranges ◽

Northern Edge ◽

Small Mammal Species ◽

White Footed Mouse

Abstract Rapid climate change is currently altering species distribution ranges. Evaluating the long-term stress level in wild species undergoing range expansion may help better understanding how species cope with the changing environment. Here, we focused on the white-footed mouse (Peromyscus leucopus), a widespread small mammal species in North-America whose distribution range is rapidly shifting northward. We evaluated long-term stress level in several populations of P. leucopus in Quebec (Canada), from the northern edge of the species distribution to more core populations in Southern Quebec. We first tested the hypothesis that populations at the range margin are under higher stress than more established populations in the southern region of our study area. We then compared four measures of long-term stress level to evaluate the congruence between these commonly used methods. We did not detect any significant geographical trend in stress level across our study populations of P. leucopus. Most notably, we found no clear congruence between the four measures of stress level we used, and conclude that these four commonly used methods are not equivalent, thereby not comparable across studies.

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