Influence of season, sex, and site availability on fisher (Martes pennanti) rest-site selection in the central hardwood forest

We monitored 20 adult fishers (8 males, 12 females) to investigate the effects of season, sex, and site availability on rest-site selection by fishers at the southern extent of their range. Data on rest-site locations (n = 219) and random sites (n = 194) were collected from December 1989 through February 1991. Fishers rested in hardwood, softwood, and mixedwood forest types in proportion to their availability in summer; however, hardwoods were used less than expected in winter. Fishers used nests, cavities, and burrows in proportion to their availability in winter. In summer, however, nests were selected twice as often as expected, cavities were used less than expected, and burrows were not used. Male fishers tended to use larger cavity trees and mixed forest stands more often than females did. In winter, fishers were not restricted to coniferous forest types, as occurs at the northern extent of their range, because moderate snow depths did not restrict movement and prey may have been more available in other forest types. Fishers appeared to select rest-site types most suitable for thermoregulation and obtaining prey. Trees with diameter at breast height ≥ 32 cm may provide cavities for rest sites in hardwood-dominated forests.

Download Full-text

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

Journal of Forest Science ◽

10.17221/45/2009-jfs ◽

2010 ◽

Vol 56 (No. 1) ◽

pp. 18-27 ◽

Cited By ~ 3

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–1) 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–1). 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–1) 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.

Download Full-text

The Spatiotemporal Pattern of the Aerosol Optical Depth (AOD) on the Canopies of Various Forest Types in the Exurban National Park: A Case in Ningbo City, Eastern China

Advances in Meteorology ◽

10.1155/2019/4942827 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Yufeng Chi ◽

Shudi Zuo ◽

Yin Ren ◽

Kaichao Chen

Keyword(s):

Growth Rate ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Coniferous Forest ◽

Mixed Forest ◽

Forest Types ◽

Average Growth Rate ◽

Average Growth ◽

Broad Leaved Forest ◽

Leaved Forest

The spatiotemporal distribution pattern of the aerosol optical depth (AOD) is influenced by many environmental factors, such as meteorological condition changes, atmospheric pollution, and topographic changes. Understanding the relationship between the vegetation land cover and the AOD would favor the improvement of forest ecosystem services. This quantitative research integrated remote sensing and ground survey data and used spatial statistical methods to explore the drivers that influence the AOD of the exurban national forest park and analyze the differences between various forest types. The driver analysis was carried out in the hot (Z ≥ 1.64) and cold (Z ≤ −1.64) spots of AOD in 2010 and 2017. Our results showed that (1) the forest type was proved to be the main factor contributing to the AOD pattern and (2) from 2010 to 2017, the average growth rate of broad-leaved forest, coniferous forest, bamboo, and shrub in hot spots was significantly higher than that in cold spots, while there was no significant difference in the mixed forest. The average growth rate of biomass densities of bamboo, coniferous forest, and mixed forest were higher than that of the shrub and broad-leaved forest. These findings provided the guidance for the rational allocation of tree species to increase the biomass and improve the ecosystem service values of forest parks.

Download Full-text

Effects of Ageratina adenophora Invasion on the Understory Community and Soil Phosphorus Characteristics of Different Forest Types in Southwest China

Forests ◽

10.3390/f11080806 ◽

2020 ◽

Vol 11 (8) ◽

pp. 806

Author(s):

Xiaoni Wu ◽

Changqun Duan ◽

Denggao Fu ◽

Peiyuan Peng ◽

Luoqi Zhao ◽

...

Keyword(s):

Invasive Species ◽

Functional Diversity ◽

Soil Phosphorus ◽

Coniferous Forest ◽

Mixed Forest ◽

Ecosystem Structure ◽

Forest Types ◽

Functional Richness ◽

Ageratina Adenophora ◽

Understory Communities

Understanding the influence of invasive species on community composition and ecosystem properties is necessary to maintain ecosystem functions. However, little is known about how understory plant communities and soil nutrients respond to invasion under different land cover types. Here, we investigated the effects of the invasive species Ageratina adenophora on the species and functional diversity of understory communities and on soil phosphorus (P) status in three forest types: CF, coniferous forest; MF, coniferous and broadleaf mixed forest; and EBF, evergreen broadleaf forest. We found that the species and functional diversity indices of the understory community significantly varied by forest type. Among the invaded plots, the greatest decrease in functional diversity (functional richness, functional divergence, and functional dispersion) and biotic homogenization were found in the CF rather than the MF or EBF. In addition, the invasion by A. adenophora significantly increased the soil NaHCO3-extractable inorganic P and organic P in the MF and EBF, respectively, while obviously decreasing the soil maximum P sorption capacity and maximum buffering capacity in the CF. However, the changes in the species and functional attributes of the understory communities were weakly associated with changes in the soil P status, probably because of the different response times to invasion in different forest types. The implication of these changes for ecosystem structure and function must be separately considered when predicting and managing invasion at a landscape scale.

Download Full-text

Comparative Analysis of Seasonal Landsat 8 Images for Forest Aboveground Biomass Estimation in a Subtropical Forest

Forests ◽

10.3390/f11010045 ◽

2019 ◽

Vol 11 (1) ◽

pp. 45 ◽

Cited By ~ 2

Author(s):

Chao Li ◽

Mingyang Li ◽

Jie Liu ◽

Yingchang Li ◽

Qianshi Dai

Keyword(s):

Aboveground Biomass ◽

Regional Scale ◽

Coniferous Forest ◽

Mixed Forest ◽

Subtropical Forest ◽

Acquisition Time ◽

Biomass Estimation ◽

Landsat 8 ◽

Forest Types ◽

Forest Aboveground Biomass

To effectively further research the regional carbon sink, it is important to estimate forest aboveground biomass (AGB). Based on optical images, the AGB can be estimated and mapped on a regional scale. The Landsat 8 Operational Land Imager (OLI) has, therefore, been widely used for regional scale AGB estimation; however, most studies have been based solely on peak season images without performance comparison of other seasons; this may ultimately affect the accuracy of AGB estimation. To explore the effects of utilizing various seasonal images for AGB estimation, we analyzed seasonal images collected using Landsat 8 OLI for a subtropical forest in northern Hunan, China. We then performed stepwise regression to estimate AGB of different forest types (coniferous forest, broadleaf forest, mixed forest and total vegetation). The model performances using seasonal images of different forest types were then compared. The results showed that textural information played an important role in AGB estimation of each forest type. Stratification based on forest types resulted in better AGB estimation model performances than those of total vegetation. The most accurate AGB estimations were achieved using the autumn (October) image, and the least accurate AGB estimations were achieved using the peak season (August) image. In addition, the uncertainties associated with the peak season image were largest in terms of AGB values < 25 Mg/ha and >75 Mg/ha, and the quality of the AGB map depicting the peak season was poorer than the maps depicting other seasons. This study suggests that the acquisition time of forest images can affect AGB estimations in subtropical forest. Therefore, future research should consider and incorporate seasonal time-series images to improve AGB estimation.

Download Full-text

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

Forestry Engineering Journal ◽

10.12737/25192 ◽

2017 ◽

Vol 7 (1) ◽

pp. 49-58 ◽

Cited By ~ 1

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

Download Full-text

Uncertainty in expert knowledge of forest succession: A case study from boreal Ontario

The Forestry Chronicle ◽

10.5558/tfc84194-2 ◽

2008 ◽

Vol 84 (2) ◽

pp. 194-209 ◽

Cited By ~ 15

Author(s):

M. Drescher ◽

A H Perera ◽

L J Buse ◽

K. Ride ◽

S. Vasiliauskas

Keyword(s):

Forest Management ◽

Expert Knowledge ◽

Forest Succession ◽

Coniferous Forest ◽

Mixed Forest ◽

Management Decision ◽

Forest Types ◽

Complex Species ◽

Forest Management Planning ◽

Environmental Controls

Expert knowledge of forest succession is used widely in forest management planning, but its level of uncertainty is unknown. Using boreal Ontario as an example, we examined the level of uncertainty in expert knowledge of forest succession and explored possible sources of this uncertainty. Overall, the level of uncertainty associated with expert knowledge was high for all aspects of forest succession, except for post-fire species establishment. Higher levels of uncertainty were associated with knowledge of forest succession for mixed forest types and moderate site conditions, as opposed to coniferous or non-coniferous forest types and extreme dry/wet or poor/rich sites. We hypothesize that uncertainty in expert knowledge is highest when vegetation dynamics are highly stochastic as with complex species assemblages, environmental controls on succession are weak, and effects of disturbances are less drastic. Awareness about the degree of uncertainty in expert knowledge of forest succession could be incorporated into forest management decision processes. It could also help researchers to identify critical knowledge gaps to guide further studies. Key words: uncertainty assessment, post-fire establishment, natural succession, knowledge elicitation

Download Full-text

Effects of Urban Forest Types and Traits on Soil Organic Carbon Stock in Beijing

Forests ◽

10.3390/f12040394 ◽

2021 ◽

Vol 12 (4) ◽

pp. 394

Author(s):

Xinhui Xu ◽

Zhenkai Sun ◽

Zezhou Hao ◽

Qi Bian ◽

Kaiyue Wei ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Carbon Stock ◽

Urban Forest ◽

Coniferous Forest ◽

Predictor Variable ◽

Urban Forests ◽

Least Squares Regression ◽

Forest Types ◽

Organic Carbon Stock

Forests can affect soil organic carbon (SOC) quality and distribution through forest types and traits. However, much less is known about the influence of urban forests on SOC, especially in the effects of different forest types, such as coniferous and broadleaved forests. Our objectives were to assess the effects of urban forest types on the variability of SOC content (SOC concentration (SOCC) and SOC density (SOCD)) and determine the key forest traits influencing SOC. Data from 168 urban forest plots of coniferous or broadleaved forests located in the Beijing urban area were used to predict the effects of forest types and traits on SOC in three different soil layers, 0–10 cm, 10–20 cm, and 20–30 cm. The analysis of variance and multiple comparisons were used to test the differences in SOC between forest types or layers. Partial least squares regression (PLSR) was used to explain the influence of forest traits on SOC and select the significant predictors. Our results showed that in urban forests, the SOCC and SOCD values of the coniferous forest group were both significantly higher than those of the broadleaved group. The SOCC of the surface soil was significantly higher than those of the following two deep layers. In PLSR models, 42.07% of the SOCC variance and 35.83% of the SOCD variance were explained by forest traits. Diameter at breast height was selected as the best predictor variable by comparing variable importance in projection (VIP) scores in the models. The results suggest that forest types and traits could be used as an optional approach to assess the organic carbon stock in urban forest soils. This study found substantial effects of urban forest types and traits on soil organic carbon sequestration, which provides important data support for urban forest planning and management.

Download Full-text

Summer rest site selection by Appalachian eastern spotted skunks

Journal of Mammalogy ◽

10.1093/jmammal/gyz075 ◽

2019 ◽

Vol 100 (4) ◽

pp. 1295-1304 ◽

Cited By ~ 2

Author(s):

Robin Y Y Eng ◽

David S Jachowski

Keyword(s):

South Carolina ◽

Habitat Selection ◽

Site Selection ◽

Prey Availability ◽

Woody Debris ◽

Relative Probability ◽

Modeling Framework ◽

Drainage Channels ◽

Unit Increase ◽

Rest Sites

AbstractEastern spotted skunks (Spilogale putorius) have suffered a dramatic range-wide decline leading to concern that the species is likely vulnerable to extinction, but were recently discovered to persist in a portion of the southern Appalachian Mountains (United States). For 2 years we investigated habitat selection by eastern spotted skunks to develop an understanding of their habitat and conservation needs in northwestern South Carolina. We used a discrete choice modeling framework to evaluate vegetative and topographic features that we predicted would influence rest site selection by male and female spotted skunks. Using VHF telemetry, we tracked 15 spotted skunks (10 males and 5 females) to 215 day-time rest sites between the months of April and August. Spotted skunks selected rest sites in close proximity to drainage channels, where the relative probability of selection decreased 18% and 50% with every 20-m increase in distance to a drainage channel for males and females, respectively. Relative probability of selection by female spotted skunks increased 30% for every one-unit increase in coarse woody debris (CWD), and relative probability of selection by male spotted skunks increased 25% for every 10% increase in understory cover. These results are consistent with previous studies that have identified cover as important for protection from predators; however, we additionally identified CWD and drainage channels as important to habitat selection by spotted skunks. These latter attributes are likely selected based on prey availability, but alternate ecological functions of these features warrant further investigation. Preservation of understory vegetation and CWD within drainage networks might benefit conservation of eastern spotted skunks in the southern Appalachians.

Download Full-text

Exploring the Sensitivity of Subtropical Stand Aboveground Productivity to Local and Regional Climate Signals in South China

Forests ◽

10.3390/f10010071 ◽

2019 ◽

Vol 10 (1) ◽

pp. 71 ◽

Cited By ~ 1

Author(s):

Hua Zhou ◽

Yang Luo ◽

Guang Zhou ◽

Jian Yu ◽

Sher Shah ◽

...

Keyword(s):

Regional Climate ◽

Mixed Forest ◽

Single Species ◽

Forest Productivity ◽

Maximum Temperature ◽

Forest Types ◽

Monthly Average ◽

Aboveground Productivity ◽

Average Maximum ◽

Average Maximum Temperature

Subtropical forest productivity is significantly affected by both natural disturbances (local and regional climate changes) and anthropogenic activities (harvesting and planting). Monthly measures of forest aboveground productivity from natural forests (primary and secondary forests) and plantations (mixed and single-species forests) were developed to explore the sensitivity of subtropical mountain productivity to the fluctuating characteristics of climate change in South China, spanning the 35-year period from 1981 to 2015. Statistical analysis showed that climate regulation differed across different forest types. The monthly average maximum temperature, precipitation, and streamflow were positively correlated with primary and mixed-forest aboveground net primary productivity (ANPP) and its components: Wood productivity (WP) and canopy productivity (CP). However, the monthly average maximum temperature, precipitation, and streamflow were negatively correlated with secondary and single-species forest ANPP and its components. The number of dry days and minimum temperature were positively associated with secondary and single-species forest productivity, but inversely associated with primary and mixed forest productivity. The multivariate ENSO (EI Niño-Southern Oscillation) index (MEI), computed based on sea level pressure, surface temperature, surface air temperature, and cloudiness over the tropical Pacific Ocean, was significantly correlated with local monthly maximum and minimum temperatures (Tmax and Tmin), precipitation (PRE), streamflow (FLO), and the number of dry days (DD), as well as the monthly means of primary and mixed forest aboveground productivity. In particular, the mean maximum temperature increased by 2.5, 0.9, 6.5, and 0.9 °C, and the total forest aboveground productivity decreased by an average of 5.7%, 3.0%, 2.4%, and 7.8% in response to the increased extreme high temperatures and drought events during the 1986/1988, 1997/1998, 2006/2007, and 2009/2010 EI Niño periods, respectively. Subsequently, the total aboveground productivity values increased by an average of 1.1%, 3.0%, 0.3%, and 8.6% because of lagged effects after the wet La Niña periods. The main conclusions of this study demonstrated that the influence of local and regional climatic fluctuations on subtropical forest productivity significantly differed across different forests, and community position and plant diversity differences among different forest types may prevent the uniform response of subtropical mountain aboveground productivity to regional climate anomalies. Therefore, these findings may be useful for forecasting climate-induced variation in forest aboveground productivity as well as for selecting tree species for planting in reforestation practices.

Download Full-text