scholarly journals Structural Characteristics of the Main Resinous Stands from Southern Carpathians, Romania

Forests ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1029
Author(s):  
Gabriel Murariu ◽  
Lucian Dinca ◽  
Nicu Tudose ◽  
Vlad Crisan ◽  
Lucian Georgescu ◽  
...  
Keyword(s):  
Effect Size ◽  
Forest Structure ◽  
Mass Production ◽  
Management Practices ◽  
Statistical Approach ◽  
Forest Type ◽  
Abiotic Factors ◽  
Forest Site ◽  
The Impact ◽  
Southern Carpathians

The purpose of this study, which contains historical data recorded over a period of 40 years, was to identify the main factors that influence and control the level of wood mass production. The main reason was to optimize the management of forest areas and was driven by the necessity to identify factors that can influence most of the volume produced by coniferous forests located in southeast Europe. The data was collected between1980 and 2005 at the National Institute for Research and Development in Forestry, for forests located in the Southern Carpathians, Romania. The studied data refer to the parameters that model forest structure for spruce, fir, pine, and larch. These are the main resinous species found in the Southern Carpathians. The total area covered by these forests is 143,431 ha. At the forest species level, the analysis consists of 16,162 records (corresponding to the elements of the trees), covering an area of 45,008 ha for fir, 4711 ha for larch, 81,995 ha for spruce, and 11,717 ha for pine. The aim of this research has been to investigate and to assess the impact and magnitude of abiotic factors such as altitude and field aspect on forest structures from the main resinous stands located in the Southern Carpathians. Taking into account the size of the database as well as the duration for collecting data, a complete statistical and systematic approach was considered optimum. This resulted from our wish to emphasize and evaluate the influence of each analysed factor on the wood mass production level. The relationship between abiotic factors and forest structure has been analysed by using a systematic statistical approach in order to provide a useful theoretical reference for the improvement of forest management practices in the context of multiple climatic, environmental, and socio-economic challenges. These common characteristics have been found by applying ANOVA and multivariate statistical methods such as PCA and FA methods. A series of parameters were considered in this investigation, namely altitude (ALT), forest site type (TS), forest type (TP), consistency (CONS) etc. In order to obtain a complete image, we have also applied multivariate analysis methods that emphasize the effect size for each database parameter. At such a level of recorded data, the statistical approach ensures a factor level of p <0.001 while the accuracy in evaluating effect size is increased. As such, they influence the spreading and structure of the studied resinous stands to a higher degree, regardless of species.

scholarly journals Forest Site and Type Variability in ALS-Based Forest Resource Inventory Attribute Predictions over Three Ontario Forest Sites

Forests ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 226 ◽  
Author(s):  
Karin van Ewijk ◽  
Paul Treitz ◽  
Murray Woods ◽  
Trevor Jones ◽  
John Caspersen
Keyword(s):  
Prediction Accuracy ◽  
Forest Type ◽  
Stem Density ◽  
Forest Site ◽  
Forest Resource ◽  
Forest Types ◽  
Resource Inventory ◽  
Forest Resource Inventory ◽  
Forest Attributes ◽  
The Impact

Over the last decade, spatially-explicit modeling of landscape-scale forest attributes for forest inventories has greatly benefitted from airborne laser scanning (ALS) and the area-based approach (ABA) to derive wall-to-wall maps of these forest attributes. Which ALS-derived metrics to include when modeling forest inventory attributes, and how prediction accuracies vary over forest types depends largely on the structural complexity of the forest(s) being studied. Hence, the purpose of this study was to (i) examine the usefulness of adding texture and intensity metrics to height-based ALS metrics for the prediction of several forest resource inventory (FRI) attributes in one boreal and two Great Lakes, St. Lawrence (GLSL) forest region sites in Ontario and (ii) quantify and compare the site and forest type variability within the context of the FRI prediction accuracies. Basal area (BA), quadratic mean diameter-at-breast height (QMD), and stem density (S) were predicted using the ABA and a nonparametric Random Forests (RF) regression model. At the site level, prediction accuracies (i.e., expressed as RMSE (Root Mean Square Error), bias, and R2) improved at the three sites when texture and intensity metrics were included in the predictor set, even though no significant differences (p > 0.05) could be detected using the nonparametric RMANOVA test. Stem density benefitted the most from the inclusion of texture and intensity, particularly in the GLSL sites (% RMSE improved up to 6%). Combining site and forest type results indicated that improvements in site level predictions, due to the addition of texture and intensity metrics to the ALS predictor set, were the result of changes in prediction accuracy in some but not all forest types present at a site and that these changes in prediction accuracy were site and FRI attribute specific. The nonparametric Kruskal–Wallis test indicated that prediction errors between the different forest types were significantly different (p ≤ 0.01). In the boreal site, prediction accuracies for conifer forest types were higher than for deciduous and mixedwoods. Such patterns in prediction accuracy among forest types and FRI attributes could not be observed in the GLSL sites. In the Petawawa Research Forest (PRF), we did detect the impact of silvicultural treatments especially on QMD and S predictions.

scholarly journals Influence of Forest Structure and Composition on Summer Habitat Use of Wildlife in an Upland Hardwood Forest

Diversity ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 160 ◽  
Author(s):  
Brent S. Pease ◽  
Eric J. Holzmueller ◽  
Clayton K. Nielsen
Keyword(s):  
Habitat Use ◽  
Forest Structure ◽  
Sugar Maple ◽  
Management Practices ◽  
Negative Relationship ◽  
Hardwood Forest ◽  
Forest Composition ◽  
Gray Squirrel ◽  
The Impact ◽  
Eastern Gray Squirrel

Oak-hickory (Quercus-Carya spp.) forest types are widespread across the midwestern United States, but changes in forest disturbance regimes are resulting in little to no oak recruitment and a compositional shift to shade-tolerant, mesophytic species, such as American beech (Fagus grandifolia) and sugar maple (Acer saccharum). We conducted camera trap surveys in a mature upland hardwood forest of southern Illinois, USA during May to August 2015–2016 to document mammal summer habitat use in relation to forest structure and composition to further understand how regional shifts in forests may affect mammal communities. With nearly 4000 camera days of effort, we modeled occupancy patterns for white-tailed deer (Odocoileus virginianus), raccoon (Procyon lotor), and eastern gray squirrel (Sciurus canadensis). Forest composition models outcompeted forest structure models for white-tailed deer, where we observed a statistically significant negative relationship between white-tailed deer habitat use and beech dominance. Further, we found a strong, positive association between deer and oak dominance. Model selection indicated little support for within-stand forest structure or composition characteristics influencing habitat use for raccoons. Eastern gray squirrel occurrence was best described by forest composition, revealing a positive relationship with beech–maple importance values. Our predictive models indicated that the impact of forest changes underway will have varying impacts on wildlife species. We can expect changes in habitat use patterns to be more pronounced with time barring revised forest management practices, and these changes are likely to be most influential at the landscape-scale. We conclude that a patchwork mosaic of forest conditions will likely best support a diverse and abundant mammal community across the region.

scholarly journals Evaluating The Impact of Roads On The Diversity Pattern And Density of Trees To Improve The Conservation of Species

2021 ◽  
Author(s):  
Uzair Aslam Bhatti ◽  
Zhaoyuan Yu ◽  
Linwang Yuan ◽  
Luo Wen ◽  
Saqib Ali Nawaz ◽  
...  
Keyword(s):  
Native Species ◽  
Management Practices ◽  
Urban Forest ◽  
Abiotic Factors ◽  
Pairwise Distance ◽  
Ecological Environment ◽  
Plant Management ◽  
Diversity Pattern ◽  
Significant Difference ◽  
The Impact

Abstract Roads have a great impact on the structure and functioning of the diversity pattern in an ecological environment and play the role of altering biotic and abiotic factors. Clusters of plants grow along the roadside due to the interplay between the arrival of propagule and seedling establishment, which depends on the road’s specifications, land pattern, and road administration and protection practices. It is very important to study the diversity pattern in a metropolitan city to improve the ecological environment. Karachi is one of the world’s largest and fastest-growing metropolitan cities; however, little is known about the urban forest of the area. In Karachi, which is in the province of Sindh, Pakistan, roadside trees along various road types (e.g., wide, medium and narrow roads) have been studied. Based on a field study, various measures of diversity were utilized to investigate the diversity of tree species on different types of paths. A total of 180 plots, divided into three primary road groups, were surveyed. The highest quantity of tree biomass per unit area was found on wide roads, followed by medium roads. On narrow roads, the least biomass was detected. A single species or a limited number of species dominated the diversity of species. Conocarpus erectus was the most dominant non-native species along all types of roads, followed by the species Guaiacum officinale. A total of 76 species (32 non-native and 44 native) that were selectively spread along the roadsides of the city were studied. There was a significant difference in phylogenetic diversity (PD), phylogenetic mean pairwise distance (MPD) and phylogenetic mean nearest taxon distance (MNTD) between wide, medium, and narrow roads. Management practices have a significant positive correlation with diversity indices. Our study identified patterns of diversity in roadside trees in Karachi. It provided the basis for future plant conservation planning, such as the conservation of plant species, the maintenance of plant habitats, and the coordination of plant management in Karachi.

scholarly journals A meta-analysis on the impacts of partial cutting on forest structure and carbon storage

2013 ◽  
Vol 10 (1) ◽  
pp. 787-813 ◽  
Author(s):  
D. Zhou ◽  
S. Q. Zhao ◽  
S. Liu ◽  
J. Oeding
Keyword(s):  
Forest Structure ◽  
Forest Floor ◽  
Management Practices ◽  
Forest Type ◽  
Meta Analysis ◽  
Mineral Soil ◽  
Basal Area ◽  
Partial Cutting ◽  
Soil C ◽  
C Storage

Abstract. Partial cutting, which removes some individual trees from a forest, is one of the major and widespread forest management practices that can significantly alter both forest structure and carbon (C) storage. Using 746 observations from 82 publications, we synthesized the impacts of partial cutting on three variables associated with forest structure (i.e. mean annual growth of diameter at breast height (DBH), basal area (BA), and volume) and four variables related to various C stock components (i.e. aboveground biomass C (AGBC), understory C, forest floor C, and mineral soil C). Results shows that the growth of DBH elevated by 112% after partial cutting, compared to the uncut control, while stand BA and volume reduced immediately by 34% and 29%, respectively. On average, partial cutting reduced AGBC by 43%, increased understory C storage by 392%, but did not show significant effects on C storages on forest floor and in mineral soil. All the effects on DBH growth, stand BA, volume, and AGBC intensified linearly with cutting intensity (CI) and decreased linearly with the number of recovery years (RY). In addition to the strong impacts of CI and RY, other factors such as climate zone and forest type also affected forest responses to partial cutting. The data assembled in this synthesis were not sufficient to determine how long it would take for a complete recovery after cutting because long-term experiments were rare. Future efforts should be tailored to increase the duration of the experiments and balance geographic locations of field studies.

Different management practices impact on CO2 and H2O budget of wind disturbed forest sites- 5-year dataset

2020 ◽  
Author(s):  
Klaudia Ziemblinska ◽  
Janusz Olejnik ◽  
Marek Urbaniak ◽  
Stanislaw Malek
Keyword(s):  
Forest Management ◽  
Forest Restoration ◽  
Management Practices ◽  
Soil Cover ◽  
Soil Conditions ◽  
Organic Layer ◽  
Forest Site ◽  
Forest Management Practices ◽  
Soil Preparation ◽  
The Impact

&lt;p&gt;There is evidence of increasing severity of extreme meteorological events, which due to climate warming are also more frequent than in the past few decades. Any disturbances (either natural or anthropogenic) exert a significant influence on the forest&amp;#8217;s functioning. In Canada and the USA, fires and insect outbreaks cause the greatest damage while in Europe wind disturbances are the main threat. Since in Poland the majority of forests are managed by the State Forests, after such events disturbed areas are almost immediately designated for reforestation. While natural regeneration still contributes the least to forest restoration, the most common practices in our country include harvesting, soil preparation (ploughing) and manual seedlings introduction, which in this sense is similar to clear-cut&amp;#8217;s management.&amp;#160;&lt;/p&gt;&lt;p&gt;Once such an event happened in Poland two EC stations were set up in the area of an 80-year old pine forest, which had been wiped out by a tornado in July 2012, to asses the impact of forest management. To date, there have been more than 5 full years of continuous carbon and energy fluxes measurement, allowing insight into forest regeneration patterns due to manual reforestation, as well as differences in CO&lt;sub&gt;2&lt;/sub&gt; losses connected to chosen treatments. The two sites (Tlen I and Tlen II) differ mostly in terms of soil preparation &amp;#8211; at Tlen I site soil was ploughed before replanting and at Tlen II soil cover remained almost intact. Additionally, at the second location, only trunks and main branches were harvested, while all uprooted stumps were left to decompose. Both meteorological and soil conditions have been investigated, with most of them not being significantly different, which allowed drawing the conclusion that observed differences in GHGs balance &lt;span&gt;are most likely related to chosen forest management practices&lt;/span&gt;. Thorough analysis of quality checked EC data revealed that in 5-year perspective the application of traditional method (Tlen I site), mainly due to soil ploughing, resulted in much less total CO&lt;sub&gt;2&lt;/sub&gt; loss to the atmosphere, reaching C-neutrality point in only 6 years after the damage as well as better seedling growth in general in comparison to the technique, where the soil cover was not disrupted. Moreover, it seems that furrows created at the conventionally managed forest site (&amp;#8220;double&amp;#8221; organic layer) serve as crucial water reservoirs during water shortage periods, preventing from the pine plantation damage caused by prolonged droughts.&lt;/p&gt;&lt;p&gt;This work advances our understanding of how different forest management practices can help to sustain the least CO&lt;sub&gt;2&lt;/sub&gt; losses on the example of wind-disturbed forests. Although, it has to be remembered that long-term studies are needed to point the best option from the perspective of climate change mitigation.&amp;#160;&lt;/p&gt;

scholarly journals The impact of invertebrate pests on pasture persistence and their interrelationship with biotic and abiotic factors

2011 ◽  
Vol 15 ◽  
pp. 109-117
Author(s):  
S.M. Zydenbos ◽  
B.I.P. Barratt ◽  
N.L. Bell ◽  
C.M. Ferguson ◽  
P.J. Gerard ◽  
...  
Keyword(s):  
Soil Fertility ◽  
Plant Pathogens ◽  
Management Practices ◽  
Abiotic Factors ◽  
Insect Damage ◽  
Long Term Effects ◽  
Pasture Management ◽  
Biotic And Abiotic Factors ◽  
Positive Effects ◽  
The Impact

New Zealand pastures are host to a range of native and exotic invertebrates. Many of these are pests that feed on the sown plant species, often causing plant death and deterioration in the productivity and persistence of the sward. While most research has focused on pest biology and control, studies of plant productivity show dramatic acute (short-medium term) and chronic (longterm) effects. For example, grass grub has been reported to cause 50% losses to ryegrass swards and Argentine stem weevil can cause a 20% loss of productivity, but the long term effects through loss of the sown species and changes in composition can be even more severe. Insect damage can be exacerbated by other biotic (e.g. weed invasion, grazing animals, plant pathogens) or abiotic factors (e.g. climate, soil fertility) to further reduce plant persistence. Some biotic and abiotic factors may interact with insect pests to have positive effects on pasture persistence, e.g. biocontrol agents that reduce pest density or addition of fertiliser to enable plants to recover from insect damage. For many pasture pests, knowledge of their ecology is based on research from over 20 years ago that, while still valid, needs to be updated to account for modern intensive pasture management practices, such as intensive grazing with a lack of reseeding, and new cultivars. To improve pasture persistence, integrated research programmes are needed that examine the relative importance of all factors contributing to plant survival and develop strategies to mitigate their effects. Keywords: Argentine stem weevil, black beetle, clover root weevil, drought, grass grub, grazing pressure, manuka beetle, nematodes, pasture persistence, pasture quality, pasture yield, porina, soil fertility, striped chafer.

The Impact of Shariah Governance and Corporate Governance on the Risk Management Practices: Evidence from Local and Foreign Islamic Banks in Malaysia

2018 ◽  
Vol 15 (2) ◽  
pp. 1-20
Author(s):  
Sabri Embi ◽  
Zurina Shafii
Keyword(s):  
Risk Management ◽  
Corporate Governance ◽  
Management Practices ◽  
Principal Component ◽  
T Test ◽  
The Body ◽  
Primary Data ◽  
Islamic Banks ◽  
Shariah Governance ◽  
The Impact

The purpose of this study is to examine the impact of Shariah governance and corporate governance (CG) on the risk management practices (RMPs) of local Islamic banks and foreign Islamic banks operating in Malaysia. The Shariah governance comprises the Shariah review (SR) and Shariah audit (SA) variables. The study also evaluates the level of RMPs, CG, SR, and SA between these two type of banks. With the aid of SPSS version 20, the items for RMPs, CG, SR, and SA were subjected to principal component analysis (PCA). From the PCA, one component or factor was extracted each for the CG, SR, and RMPs while another two factors were extracted for the SA. Primary data was collected using a self-administered survey questionnaire. The questionnaire covers four aspects ; CG, SR, SA, and RMPs. The data received from the 300 usable questionnaires were subjected to correlation and regression analyses as well as an independent t-test. The result of correlation analysis shows that all the four variables have large positive correlations with each other indicating a strong and significant relationship between them. From the regression analysis undertaken, CG, SR, and SA together explained 52.3 percent of the RMPs and CG emerged as the most influential variable that impacts the RMPs. The independent t-test carried out shows that there were significant differences in the CG and SA between the local and foreign Islamic banks. However, there were no significant differences between the two types of the bank in relation to SR and RMPs. The study has contributed to the body of knowledge and is beneficial to academicians, industry players, regulators, and other stakeholders.

Characterizing the impact of recovering sea otters on commercially important crabs in California estuaries

2020 ◽  
Vol 655 ◽  
pp. 123-137
Author(s):  
TM Grimes ◽  
MT Tinker ◽  
BB Hughes ◽  
KE Boyer ◽  
L Needles ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Sea Otter ◽  
Dungeness Crab ◽  
Sea Otters ◽  
Elkhorn Slough ◽  
Enhydra Lutris Nereis ◽  
Crab Abundance ◽  
Population Sizes ◽  
Commercially Important ◽  
The Impact

Protective legislation and management have led to an increase in California’s sea otter Enhydra lutris nereis population. While sea otter recovery has been linked to ecosystem benefits, sea otter predation may negatively affect commercially valuable species. Understanding the potential influence of sea otters is of particular importance as their range expands into estuaries that function as nurseries for commercially valuable species like Dungeness crab Metacarcinus magister. We consider how sea otter predation has affected the abundance and size of juvenile Dungeness crab in Elkhorn Slough, California, USA, and analyzed cancrid crab abundance and size across 4 California estuaries with and without sea otters to understand how biotic and abiotic factors contribute to observed variation in crab size and abundance. We compared trends in southern sea otters relative to Dungeness crab landings in California to assess whether increasing sea otter abundance have negatively impacted landings. In Elkhorn Slough, juvenile Dungeness crab abundance and size have declined since 2012, coinciding with sea otter population growth. However, the impact of sea otters on juvenile Dungeness crab size was habitat-specific and only significant in unvegetated habitat. Across estuaries, we found that cancrid crab abundance and size were negatively associated with sea otter presence. While abiotic factors varied among estuaries, these factors explained little of the observed variation in crab abundance or size. Although we found evidence that sea otters can have localized effects on cancrid crab populations within estuaries, we found no evidence that southern sea otters, at recent population sizes, have negatively impacted Dungeness crab landings in California from 2000-2014.

To Study & Implementation the Impact of Youth Mentoring

GIS Business ◽  
2019 ◽  
Vol 14 (4) ◽  
pp. 122-129
Author(s):  
Monika Bansal ◽  
Sh. Lbs Arya Mahila
Keyword(s):  
Young People ◽  
Effect Size ◽  
Professional Growth ◽  
Young Person ◽  
Youth Mentoring ◽  
Self Development ◽  
Study Implementation ◽  
Responsible Adult ◽  
The Impact

Youth Mentoring is the process of matching mentors with young people who need or want a caring responsible adult in their lives. It is defined as an on-going relationship between a caring adult and a young person which is required for self-development, professional growth and carrier development of the mentee and mentors both and all this must be placed within a specific institution context. The purpose of this article is to quantitatively review the three major areas of mentoring research (youth, academic, and workplace) to determine the overall effect size associated with mentoring outcomes for students.

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