Response of beaver, moose, and snowshoe hare to clear-cutting in a Quebec boreal forest: a reassessment 10 years after cut

2005 ◽  
Vol 35 (1) ◽  
pp. 151-160 ◽  
Author(s):  
François Potvin ◽  
Laurier Breton ◽  
Réhaume Courtois
Keyword(s):  
Riparian Forest ◽  
Castor Canadensis ◽  
Coniferous Forest ◽  
Mixed Forest ◽  
Snowshoe Hare ◽  
Habitat Conditions ◽  
Mixed Stands ◽  
Control Block ◽  
Clear Cutting ◽  
Rate Of Increase

We studied the response of beaver (Castor canadensis Kuhl), moose (Alces alces L.), and snowshoe hare (Lepus americanus Erxl.) to clear-cutting in three blocks that had been logged 10 years ago. In a previous study, these species had been surveyed in the same blocks 2 years before and 2 years after logging. We also surveyed an uncut block of the initial experimental design that was logged more recently. Over the 10-year period, the shrub layer and available browse have improved markedly in clear-cut areas. As compared with logged coniferous stands, logged mixed stands had higher lateral cover (62% vs. ≈55%) and taller regeneration (>4 m vs. <3 m). Beaver density did not change over the period because its feeding habitat remained unchanged in the riparian forest strips. Moose densities increased 54%–87% in two harvested blocks as a result of both logging and stricter hunting regulations (selective hunting). Based on the rate of increase observed in a control block, we estimate that a 25% density increase in the mixed forest block can be related to logging, while selective hunting can solely be responsible for the change in the coniferous forest block. Snowshoe hare have started to reoccupy logged coniferous stands, but their relative density still remained less than half that of uncut stands. We conclude that, after 10 years, logged mixed stands already offer good habitat conditions for moose and snowshoe hare. Conversely, in logged black spruce (Picea mariana (Mill.) BSP) stands, habitat conditions still remain poor for snowshoe hare because of a lack of cover.

Riparian forest strips as habitat for snowshoe hare in a boreal balsam fir forest

1998 ◽  
Vol 28 (10) ◽  
pp. 1494-1500 ◽  
Author(s):  
Marcel Darveau ◽  
Jean Huot ◽  
Louis Bélanger
Keyword(s):  
Riparian Forest ◽  
Abies Balsamea ◽  
Timber Harvesting ◽  
Habitat Characteristics ◽  
Balsam Fir ◽  
Snowshoe Hare ◽  
Buffer Effect ◽  
Clear Cutting ◽  
Local Perturbations ◽  
Open Question

Riparian forest strips are usually protected from logging for their buffer effect on aquatic habitats. However, their value to terrestrial wildlife species such as snowshoe hare (Lepus americanus Erxleben) is unknown. From 1990 to 1996, we compared habitat characteristics (shrubs and saplings 0.25-2.25 m high), hare browsing, and hare pellet densities in five types of experimental riparian forest strips (20, 40, 60, and >300 m wide intact strips, and 20 m wide thinned strips), in a humid boreal balsam fir (Abies balsamea (L.) Mill.) landscape managed primarily for timber harvesting in Quebec. Based on coniferous and deciduous shrub densities, all riparian forest strips and adjacent clearcuts remained low-quality habitats for hare over 6 years following clear-cutting. Only 103 shrubs were browsed in a 1500-m2 area sampled over 3 years, of which only 33 had >20% of browsed stems. Nevertheless, pellet data revealed a low but sustained use of all strips each summer and winter, and there were no changes over 6 years (mean 280 pellets/ha per month; P > 0.05). Whether hare populations are cyclic or not in our region remains an open question. However, they show some fluctuations and timber harvesting coincided with "high" hare populations in our study area. Sampling in "low" years might show that fewer hares occupy the forest strips. Further work is required to determine the influence of regional and local perturbations on the use of riparian forest strips by snowshoe hares.

scholarly journals THE IMPACT OF SHARE PARTICIPATION OF PINE AND SPRUCE ON INVENTORY INDICES OF MIXED FOREST STANDS

2017 ◽  
Vol 7 (1) ◽  
pp. 49-58 ◽  
Author(s):  
Данилов ◽  
Dmitriy Danilov ◽  
Беляева ◽  
Nataliia Beliaeva ◽  
Мартынов ◽  
...  
Keyword(s):  
Initial Density ◽  
Coniferous Forest ◽  
Mixed Forest ◽  
Average Height ◽  
Leningrad Region ◽  
Forest Types ◽  
Forest Stands ◽  
Mixed Stands ◽  
The Impact ◽  
Groups Of Forest Types

The influence of composition on the dynamics of inventory indices of the mixed modal forest stands is considered: ridges with the groups of forest types of middle subzone of taiga in the territory of the Leningrad region, for 60 year period. The course of growth of pine and spruce in the mixed stand is due to the composition of the stand, which affects the entire life cycle of its development. Analysis of forest inventory data at the test plots has shown that the median line for the average height and diameter has the distinction of growth from tabular reference data. Differences in the dynamics of growth in valuation metrics over the study period is due to the initial density of pine, then spruce, and the degree of difference in the age of trees. The variability of average heights and diameters on the experimental plots is influenced by the share of particular species in the composition of the stand. The stand composition significantly affects average diameter and height of tiers, composing the mixed coniferous forest that was confirmed by single-factor analysis of variance. The sum of the areas of the cross sections at the pine tier of the virtually at all experienced objects increases up to the age of 100-120 years, and in spruce this dependence is shown only up to the age of 80-85 years. Pine tier depending on the initial density has a greater impact on the composition of the mixed stands than spruce. This can be considered as a fact of environmental compliance of the conditions of the types: ridges with groups of forest types, for successful growth of pine. In mixed stands, untouched by commercial logging, the spruce element, quantitatively not exceeding the pine one, are stunted and produce less stock

scholarly journals Distribution of the timber quality attribute ‘knot surface’ in logs of Fagus sylvatica L. from pure and mixed forest stands

2021 ◽  
Author(s):  
Kirsten Höwler ◽  
Torsten Vor ◽  
Peter Schall ◽  
Peter Annighöfer ◽  
Dominik Seidel ◽  
...  
Keyword(s):  
Fagus Sylvatica ◽  
Mixed Forest ◽  
European Beech ◽  
Forest Stands ◽  
Species Identity ◽  
Mixed Stands ◽  
Mixed Forests ◽  
Climate Conditions ◽  
Timber Quality ◽  
Positive Effects

AbstractResearch on mixed forests has mostly focused on tree growth and productivity, or resistance and resilience in changing climate conditions, but only rarely on the effects of tree species mixing on timber quality. In particular, it is still unclear whether the numerous positive effects of mixed forests on productivity and stability come at the expense of timber quality. In this study, we used photographs of sawn boards from 90 European beech (Fagus sylvatica L.) trees of mixed and pure forest stands to analyze internal timber quality through the quality indicator knot surface that was quantitatively assessed using the software Datinf® Measure. We observed a decrease in knot surface with increasing distance from the pith as well as smaller values in the lower log sections. Regarding the influence of neighborhood species identity, we found only minor effects meaning that timber qualities in mixed stands of beech and Norway spruce (Picea abies (L.) H. Karst.) tended to be slightly worse compared to pure beech stands.

scholarly journals Object Oriented Classification for Mapping Mixed and Pure Forest Stands Using Very-High Resolution Imagery

2021 ◽  
Vol 13 (13) ◽  
pp. 2508
Author(s):  
Loredana Oreti ◽  
Diego Giuliarelli ◽  
Antonio Tomao ◽  
Anna Barbati
Keyword(s):  
High Resolution ◽  
Spatial Scales ◽  
Parametric Method ◽  
Mixed Forest ◽  
Mixed Stands ◽  
Mapping Unit ◽  
Mixed Forests ◽  
High Resolution Imagery ◽  
Very High Resolution Imagery ◽  
Very High

The importance of mixed forests is increasingly recognized on a scientific level, due to their greater productivity and efficiency in resource use, compared to pure stands. However, a reliable quantification of the actual spatial extent of mixed stands on a fine spatial scale is still lacking. Indeed, classification and mapping of mixed populations, especially with semi-automatic procedures, has been a challenging issue up to date. The main objective of this study is to evaluate the potential of Object-Based Image Analysis (OBIA) and Very-High-Resolution imagery (VHR) to detect and map mixed forests of broadleaves and coniferous trees with a Minimum Mapping Unit (MMU) of 500 m2. This study evaluates segmentation-based classification paired with non-parametric method K- nearest-neighbors (K-NN), trained with a dataset independent from the validation one. The forest area mapped as mixed forest canopies in the study area amounts to 11%, with an overall accuracy being equal to 85% and K of 0.78. Better levels of user and producer accuracies (85–93%) are reached in conifer and broadleaved dominated stands. The study findings demonstrate that the very high resolution images (0.20 m of spatial resolutions) can be reliably used to detect the fine-grained pattern of rare mixed forests, thus supporting the monitoring and management of forest resources also on fine spatial scales.

Competition theory — science and application in mixed forest stands: review of experimental and modelling methods and suggestions for future research

2013 ◽  
Vol 21 (2) ◽  
pp. 71-84 ◽  
Author(s):  
Guy R. Larocque ◽  
Nancy Luckai ◽  
Shailendra N. Adhikary ◽  
Arthur Groot ◽  
F. Wayne Bell ◽  
...  
Keyword(s):  
Mixed Forest ◽  
Single Species ◽  
Experimental Designs ◽  
Competitive Interactions ◽  
Future Research ◽  
Relative Importance ◽  
Forest Stands ◽  
Management Scenarios ◽  
Mixed Stands ◽  
Individual Tree

Competition in forest stands has long been of interest to researchers. However, much of the knowledge originates from empirical studies that examined the effects of competition. For instance, many studies were focused on the effects of the presence of herbaceous species on the development of tree seedlings or the decrease in individual tree growth with increases in stand density. Several models that incorporate competitive effects have been developed to predict tree and stand growth, but with simplified representations of competitive interactions. While these studies provided guidance useful for forest management, they contributed only partially to furthering our understanding of competitive mechanisms. Also, most competition studies were conducted in single-species stands. As competitive interactions occurring in mixed stands are characterized by a higher degree of complexity than those in single-species stands, a better understanding of these mechanisms can contribute to developing optimal management scenarios. The dynamics of forest stands with at least two species may be affected not only by competition, but also by facilitation or complementarity mechanisms. Thus, knowledge of the mechanisms may provide insight into the relative importance of intra- versus inter-specific competition and whether competition is symmetric or asymmetric. Special attention to the implementation of field experimental designs is warranted for mixed stands. While traditional spacing trials are appropriate for single-species stands, the examination of competitive interactions in mixed stands requires more complex experimental designs to examine the relative importance of species combinations. Forest productivity models allow resource managers to test different management scenarios, but again most of these models were developed for single-species stands. As competitive interactions are more complex in mixed stands, models developed to predict their dynamics will need to include more mechanistic representations of competition.

scholarly journals Does the Mixture of Species change the C:N:P Ecological Stoichiometric Characteristics of fine Roots? A Case Study of Cupressus Funebris Mixed Forest

2021 ◽  
Author(s):  
Wenchun He ◽  
Yang Wang ◽  
Xiaochen Wen ◽  
Yu Wang ◽  
Baoru Xiao ◽  
...  
Keyword(s):  
Fine Roots ◽  
Environmental Changes ◽  
Mixed Forest ◽  
Chemical Properties ◽  
Available Phosphorus ◽  
Biological Factors ◽  
Nitrogen And Phosphorus ◽  
Mixed Stands ◽  
Available Nitrogen ◽  
Low Efficiency

Abstract The growth of fine roots of trees is affected by environmental changes and biological factors. At present, there have been many researches on the physiological plasticity of fine roots caused by environmental changes, but there are still few studies on the influence of biological factors on fine roots. This paper focused on the contents of carbon (C), nitrogen (N), and phosphorus (P), and their ecological stoichiometric ratios in different root orders of Cupressus funebris fine roots in 11 mixed stands with Koelreuteria paniculate or Toona sinensis at different ratios, and the effects of soil physical and chemical properties on the root chemical properties. It aimed to provide new insights into the fine-root nutrient distribution pattern and the transformation or reconstruction of low-efficiency pure forests from the standpoint of forest types. The results showed that: soil pH, and the content of available nitrogen (SAN), available phosphorus (SAP) and available potassium (SAK) differed significantly in the tested mixed forest stands. No significant differences in carbon content of fine roots were observed in different mixed stands. The content of nitrogen and phosphorus in fine roots in mixed forests showed heterogeneity. Species mixing changed the C/N, C/P and N/P of the C. funebris compared the pure stands. The "T. sinensis + C. funebris" forest alleviated the limitation of the lack of phosphorus on fine roots of C. funebris on. The principal component analysis showed that mixed stands of "T. sinensis + C. funebris" had the highest comprehensive score at ratio of "3:1". Thus, our results recommended the adoption of T. sinensis, especially at 75%, to reconstruct the low-efficiency pure C. funebris forest.

scholarly journals Estimation of Tree Heights in an Uneven-Aged, Mixed Forest in Northern Iran Using Artificial Intelligence and Empirical Models

Forests ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 324 ◽  
Author(s):  
Mahmoud Bayat ◽  
Pete Bettinger ◽  
Sahar Heidari ◽  
Azad Henareh Khalyani ◽  
Meghdad Jourgholami ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Mixed Forest ◽  
Empirical Models ◽  
Ann Model ◽  
Mixed Stands ◽  
Anfis Model ◽  
Northern Iran ◽  
Inference System ◽  
Intelligence Models ◽  
Artificial Intelligence Models

The diameters and heights of trees are two of the most important components in a forest inventory. In some circumstances, the heights of trees need to be estimated due to the time and cost involved in measuring them in the field. Artificial intelligence models have many advantages in modeling nonlinear height–diameter relationships of trees, which sometimes make them more useful than empirical models in estimating the heights of trees. In the present study, the heights of trees in uneven-aged and mixed stands in the high elevation forests of northern Iran were estimated using an artificial neural network (ANN) model, an adaptive neuro-fuzzy inference system (ANFIS) model, and empirical models. A systematic sampling method with a 150 × 200 m network (0.1 ha area) was employed. The diameters and heights of 516 trees were measured to support the modeling effort. Using 10 nonlinear empirical models, the ANN model, and the ANFIS model, the relationship between height as a dependent variable and diameter as an independent variable was analyzed. The results show, according to R2, relative root mean square error (RMSE), and other model evaluation criteria, that there is a greater consistency between predicted height and observed height when using artificial intelligence models (R2 = 0.78; RMSE (%) = 18.49) than when using regression analysis (R2 = 0.68; RMSE (%) = 17.69). Thus, it can be said that these models may be better than empirical models for predicting the heights of common, commercially-important trees in the study area.

scholarly journals Stand-Level Transpiration Increases after Eastern Redcedar (Juniperus virginiana L.) Encroachment into the Midstory of Oak Forests

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 901 ◽  
Author(s):  
Patricia R. Torquato ◽  
Rodney E. Will ◽  
Bo Zhang ◽  
Chris B. Zou
Keyword(s):  
Water Use ◽  
Sap Flow ◽  
Structural Equation ◽  
Mixed Forest ◽  
Flow Density ◽  
Juniperus Virginiana ◽  
Cross Timbers ◽  
Eastern Redcedar ◽  
Mixed Species ◽  
Mixed Stands

Eastern redcedar (Juniperus virginiana L., redcedar) encroachment is transitioning the oak-dominated Cross-Timbers of the southern Great Plain of the USA into mixed-species forests. However, it remains unknown how the re-assemblage of tree species in a semiarid to sub-humid climate affects species-specific water use and competition, and ultimately the ecosystem-level water budget. We selected three sites representative of oak, redcedar, and oak and redcedar mixed stands with a similar total basal area (BA) in a Cross-Timbers forest near Stillwater, Oklahoma. Sap flow sensors were installed in a subset of trees in each stand representing the distribution of diameter at breast height (DBH). Sap flow of each selected tree was continuously monitored over a period of 20 months, encompassing two growing seasons between May 2017 and December 2018. Results showed that the mean sap flow density (Sd) of redcedar was usually higher than post oaks (Quercus stellata Wangenh.). A structural equation model showed a significant correlation between Sd and shallow soil moisture for redcedar but not for post oak. At the stand level, the annual water use of the mixed species stand was greater than the redcedar or oak stand of similar total BA. The transition of oak-dominated Cross-Timbers to redcedar and oak mixed forest will increase stand-level transpiration, potentially reducing the water available for runoff or recharge to groundwater.

scholarly journals Variation of conducting area in stems of European larch (Larix deciduas) growing in fresh mixed coniferous forest and fresh mixed forest sites

2010 ◽  
Vol 56 (No. 1) ◽  
pp. 18-27 ◽  
Author(s):  
M. Nawrot ◽  
M. Jakubowski ◽  
W. Pazdrowski ◽  
K. Kaźmierczak ◽  
M. Szymański
Keyword(s):  
Coniferous Forest ◽  
Mixed Forest ◽  
Coefficient Of Determination ◽  
Forest Site ◽  
Age Classes ◽  
Main Crop ◽  
Forest Sites ◽  
The Social ◽  
Individual Trees ◽  
Site Types

The paper presents an attempt to determine conducting area (CA), relative conducting area (CA.k<sup>–1</sup>) and mean ring conducting area (CAar) on discs cut at breast height from stems of larch trees growing in fresh mixed coniferous forest and fresh mixed forest sites, representing four age classes and the main crop according to Kraft’s classification. The value of CA increases with an improvement of the social class of tree position in the community, while no such dependences were found for the value of (CA.k<sup>–1</sup>). The parameter CAar, except for one case in age class IV in the fresh mixed coniferous forest site, increases with an improvement of the position a tree takes in the community and differentiates more markedly under the conditions of fresh mixed forest sites. Relative conducting area (CA.k<sup>–1</sup>) decreases markedly with an increase in the age of trees, which is confirmed by high values of the coefficient of determination. Moreover, the significance of differences between individual trees in the main crop according to Kraft and forest site types was tested in terms of the values of CAar. Calculated values may be used to describe the relationships between conducting area and the size of the assimilating organ more precisely than the total sapwood zone.

scholarly journals Consequences of Climate Change-Induced Habitat Conversions on Red Wood Ants in a Central European Mountain: A Case Study

Animals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1677
Author(s):  
Orsolya Juhász ◽  
Ágnes Fürjes-Mikó ◽  
Anna Tenyér ◽  
Anna Ágnes Somogyi ◽  
Dianne Joy Aguilon ◽  
...  
Keyword(s):  
Climate Change ◽  
Bark Beetle ◽  
Coniferous Forest ◽  
Food Sources ◽  
Coniferous Forests ◽  
Central European ◽  
Formica Polyctena ◽  
Clear Cutting ◽  
Red Wood Ants ◽  
Wood Ants

The consequences of anthropogenic climate change are one of the major concerns of conservation biology. A cascade of negative effects is expected to affect various ecosystems, one of which is Central European coniferous forests and their unique biota. These coniferous forests are the primary habitat of many forest specialist species such as red wood ants. Climate change-induced rising of temperature allows trees to skip winter hibernation, making them more vulnerable to storms that cause wind felling, and in turn, promotes bark beetle infestations that results in unscheduled clear-cuttings. Red wood ants can also be exposed to such habitat changes. We investigated the effects of bark beetle-induced clear-cutting and the absence of coniferous trees on colonies of Formica polyctena, including a mixed-coniferous forest as a reference. Our aim was to investigate how these habitat features affect the nest characteristics and nesting habits of F. polyctena. Our results indicate that, in the absence of conifers, F. polyctena tend to use different alternatives for nest material, colony structure, and food sources. However, the vitality of F. polyctena colonies significantly decreased (smaller nest mound volumes). Our study highlights the ecological flexibility of this forest specialist and its potential to survive under extreme conditions.

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