scholarly journals Impacts of Human Activities on Tree Species Composition Along the Forest Savanna Boundary in Nigeria

2016 ◽  
Vol 47 (2) ◽  
pp. 115 ◽  
Author(s):  
Christiana Ndidi Egbinola
Keyword(s):  
Species Composition ◽  
Tree Species ◽  
Human Activities ◽  
Detrended Correspondence Analysis ◽  
Floristic Composition ◽  
Forest Species ◽  
Tree Species Composition ◽  
Study Sites ◽  
The Impact ◽  
The Relationship

The study investigated the tree species composition along the forest-savanna boundary in Oyo state of Nigeria with the aim of assessing the impact of human activities on the floristic composition. A transect was placed along the study area and species data was collected from quadrats placed in study plots within different study sites. Detrended Correspondence Analysis (DCA) was used to determine vegetation assemblages, while both correlation and the analysis of variance (ANOVA) were used to show the relationship between species in the different study sites. Results of the DCA revealed three species assemblages, an area with only forest species, another with only savanna species and a third with both forest/savanna species. ANOVA results further revealed that within the forest and savanna assemblages, species in mature and successional sites were alike. The study therefore revealed that human activities’ within the region is leading to the establishment of savanna species and an elimination of forest species.

Long-term effects of stump removal and tree species composition on the diversity and structure of soil fungal communities

2020 ◽  
Vol 96 (5) ◽  
Author(s):  
Dixi Modi ◽  
Suzanne Simard ◽  
Jean Bérubé ◽  
Les Lavkulich ◽  
Richard Hamelin ◽  
...  
Keyword(s):  
Species Composition ◽  
Fungal Community ◽  
Tree Species ◽  
Management Practice ◽  
Tree Regeneration ◽  
Root Disease ◽  
Fungal Communities ◽  
Tree Species Composition ◽  
The Impact

ABSTRACT Stump removal is a common forest management practice used to reduce the mortality of trees affected by the fungal pathogen-mediated root disease, Armillaria root rot, but the impact of stumping on soil fungal community structure is not well understood. This study analyzed the long-term impact of stumping and tree species composition on the abundance, diversity and taxonomic composition of soil fungal communities using internal transcribed spacer (ITS) marker-based DNA metabarcoding in a 48-year-old trial at Skimikin, British Columbia. A total of 108 samples were collected from FH (fermented and humus layers), and soil mineral horizons (A and B) from stumped and unstumped plots of six tree species treatments (pure stands and admixtures of Douglas-fir, western red-cedar and paper birch). Fungal α-diversity in the A horizon significantly increased with stumping regardless of tree species composition, while β-diversity was significantly affected by stumping in all the horizons. We also observed that the relative abundance of the saprotrophic fungal community declined while that of the ectomycorrhizal fungal community increased with stumping. In conclusion, increase in ectomycorrhizal fungal associations, which are positively associated with tree productivity, suggests that stumping can be considered a good management practice for mitigating root disease and promoting tree regeneration.

scholarly journals Tree Species Composition and Structure near Road Borders in the Laurel Forest of Anaga (Tenerife – Islas Canarias)

2016 ◽  
Vol 73 (2) ◽  
pp. 145
Author(s):  
Zaira Negrín ◽  
José Ramón Arévalo
Keyword(s):  
Species Composition ◽  
Tree Species ◽  
Sampling Site ◽  
Basal Area ◽  
Tree Species Composition ◽  
Laurel Forest ◽  
The Road ◽  
Road Systems ◽  
Surrounding Landscape ◽  
Study Sites

Urbanization is one of the main causes of species extinction. Closely linked to urbanization are road systems, which are a source of biotic and abiotic effects on the surrounding landscape. The continued existence of these corridors results in enormous human activity (Forman & Alexander, 1998). In particular, roads sharply define and fragment forest ecosystems leading to changes in plant species composition and vegetation structure from road border to the surrounding interior. This paper assesses border effects on tree species richness and composition in the laurel forest of Anaga, Tenerife, Spain. Effects of anthropogenic corridors on vegetation differed among the study sites. Multivariate analysis revealed that species composition is more related to the sampling site than to the effect of the corridor, while for density, significant differences were found between the road border and forest interior but not as a regular pattern. This suggests that main corridor disturbances regarding tree basal area is limited to the immediate road edge in the laurel forest, while for species composition, no significant differences were found.

Long-term changes in tree species composition in the Dinaric mountain forests of Slovenia

2003 ◽  
Vol 79 (2) ◽  
pp. 227-232 ◽  
Author(s):  
Andrej Boncina ◽  
Franc Gaspersic ◽  
Jurij Diaci
Keyword(s):  
Species Composition ◽  
Tree Species ◽  
European Beech ◽  
Anthropogenic Factors ◽  
Silver Fir ◽  
Tree Species Composition ◽  
Virgin Forest ◽  
Forest Remnant ◽  
The Impact

This study utilizes data from long-term research sites in managed fir-beech forests (Hrusica, Leskova dolina and Rog) and a virgin forest remnant (Rajhenav), used as a reference site. Data obtained from old forest management plans and forest inventories were analysed. The results of the study support the hypothesis that two main tree species—silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.)—alternate site dominance. The causes of species dominance alternation include both natural processes and anthropogenic factors, in particular silvicultural practices and the impact of ungulates. More than a hundred years ago, European beech dominated stand volume. The proportion of silver fir increased until 1940–1970 when a gradual decrease started. All indicators suggest that the proportion of silver fir will decrease further in the coming decades. Key words: tree species composition alternation, diameter distribution, silver fir, European beech, forest history, forest planning, managed forests, virgin forest remnant

scholarly journals Combining Tree Species Composition and Understory Coverage Indicators with Optimization Techniques to Address Concerns with Landscape-Level Biodiversity

Land ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 126
Author(s):  
Brigite Botequim ◽  
Miguel N. Bugalho ◽  
Ana Raquel Rodrigues ◽  
Susete Marques ◽  
Marco Marto ◽  
...  
Keyword(s):  
Climate Change ◽  
Forest Management ◽  
Species Composition ◽  
Biodiversity Conservation ◽  
Tree Species ◽  
Optimization Techniques ◽  
Tree Species Composition ◽  
Management Models ◽  
The Impact ◽  
Landscape Level

Sustainable forest management needs to address biodiversity conservation concerns. For that purpose, forest managers need models and indicators that may help evaluate the impact of management options on biodiversity under the uncertainty of climate change scenarios. In this research we explore the potential for designing mosaics of stand-level forest management models to address biodiversity conservation objectives on a broader landscape-level. Our approach integrates (i) an effective stand-level biodiversity indicator that reflect tree species composition, stand age, and understory coverage under divergent climate conditions; and (ii) linear programming optimization techniques to guide forest actors in seeing optimal forest practices to safeguard future biodiversity. Emphasis is on the efficiency and effectiveness of an approach to help assess the impact of forest management planning on biodiversity under scenarios of climate change. Results from a resource capability model are discussed for an application to a large-scale problem encompassing 14,765 ha, extending over a 90-years planning horizon and considering two local-climate scenarios. They highlight the potential of the approach to help assess the impact of both stand and landscape-level forest management models on biodiversity conservation goals. They demonstrate further that the approach provides insights about how climate change, timber demand and wildfire resistance may impact plans that target the optimization of biodiversity values. The set of optimized long-term solutions emphasizes a multifunctional forest that guarantees a desirable local level of biodiversity and resilience to wildfires, while providing a balanced production of wood over time at the landscape scale.

scholarly journals Forest Structure and Tree Species Composition at Kuala Langat South Peat Swamp Forest, Selangor, Malaysia

2021 ◽  
Vol 15 (2) ◽  
pp. 147-161
Author(s):  
Hasya Hannani Ruziman ◽  
◽  
Faezah Pardi ◽  
◽  
Keyword(s):  
Species Composition ◽  
Forest Structure ◽  
Tree Species ◽  
Diversity Index ◽  
Floristic Composition ◽  
Swamp Forest ◽  
Tree Species Composition ◽  
Tree Distribution ◽  
Ground Biomass ◽  
Voucher Specimens

Kuala Langat South Forest Reserve (KLSFR) was the main highlight when Selangor State Agriculture Corporation proposed to acquire the whole of KLSFR (about 6,908 ha) for the establishment of oil palm plantations. Many parties expressed their concern and opposed the plan as it would lead to the destruction of the forest and its biodiversity. As such, this study was aimed to determine the forest structure and tree species composition to conserve and sustainably manage the forest. Seven plots of 40 m x 20 m covering 0.56 ha were established randomly in KLSFR. All trees with 5 cm diameter breast height (DBH) and above were tagged, measured and identified. Voucher specimens were then taken for further verification purposes. The floristic composition of KLSFR consists of 335 individuals represented by 47 tree species from 21 families. Annonaceae, Guttiferaceae and Myrsticaceae were the most speciose families with five species recorded for each family. Goniothalamus malayanus and Koompassia malaccensis were considered to have absolute dominance at the study site with Important Value index of 14.73 % and 14.19 %, respectively. KLSFR recorded low Shannon-Weiner Diversity index of H’ = 2.85 (H’max = 3.81) and Margalef’s Richness Index with DMG = 7.91. Evenness (E) index of 0.75 portrayed that the tree species are almost equally abundant in the study area. Total trees biomass was estimated at 406.90 t/ha, represented by 349.61 t/ha of above ground biomass (AGB) and 57.29 t/ha of below ground biomass (BGB). The study indicated that KLSFR has uniform distribution of individuals with mixed species composition of trees. Tree distribution showed the pattern of De iocourt’s factor procedure (inverse J distribution) where number of tree decreases with the increase in diameter, representing the natural regeneration of the forest.

The relationship of tropical bird communities to tree species composition and vegetation structure along an Andean elevational gradient

2012 ◽  
Vol 40 (5) ◽  
pp. 950-962 ◽  
Author(s):  
Jill E. Jankowski ◽  
Christopher L. Merkord ◽  
William Farfan Rios ◽  
Karina García Cabrera ◽  
Norma Salinas Revilla ◽  
...  
Keyword(s):  
Species Composition ◽  
Tree Species ◽  
Vegetation Structure ◽  
Elevational Gradient ◽  
Bird Communities ◽  
Tree Species Composition ◽  
Tropical Bird ◽  
Relationship Of ◽  
The Relationship

scholarly journals Effects of forest disturbance and regeneration on tree species composition and traits in DR Congo

2021 ◽  
Author(s):  
Jonas Depecker ◽  
Justin Anio Asimonyio ◽  
Ronald Miteho ◽  
Yves Hatangi ◽  
Jean-Leon Kambale ◽  
...  
Keyword(s):  
Species Diversity ◽  
Species Composition ◽  
Forest Structure ◽  
Tree Species ◽  
Anthropogenic Disturbance ◽  
Congo Basin ◽  
Old Growth ◽  
Tree Species Composition ◽  
Old Growth Forest ◽  
The Impact

Despite their key role in biodiversity conservation, forests of the Congo Basin are increasingly threatened by human activities. Whereas deforestation is very conspicuous, it remains challenging to monitor the impact of forest degradation under a more or less intact canopy. Likewise, the outcomes of forest regeneration following agricultural abandonment remain poorly studied in the Congo Basin. Here, we surveyed 125 vegetation quadrats across 25 forest inventory plots in the Yangambi region, and based on historical land-use maps. We aimed to assess both the impact of anthropogenic disturbance and forest recovery on tree species diversity, tree functional traits, community composition, canopy cover, and forest structure, as compared to undisturbed old-growth forest. We found that undisturbed old-growth forest harboured more tree individuals, particularly individuals with a smaller diameter, as well as species with a higher wood density when compared to both disturbed old-growth and regrowth forest. Moreover, species diversity was highest in disturbed old-growth forest. Tree species composition was significantly different between undisturbed old-growth forest and the other two forest categories. Our findings indicate that anthropogenic disturbance results in a degraded forest structure and may reduce the forest's ability to store carbon. Whereas species diversity recovered 60 years after agricultural abandonment, species composition remained different from undisturbed old-growth forest. Our study illustrates the need for more extensive vegetation surveys in the Congo Basin in order to quantify the effects of human disturbance under a closed canopy.

Langfristige Entwicklung von zwei Waldgesellschaften im Białowieża-Urwald

2008 ◽  
Vol 159 (4) ◽  
pp. 80-90 ◽  
Author(s):  
Bogdan Brzeziecki ◽  
Feliks Eugeniusz Bernadzki
Keyword(s):  
Species Composition ◽  
Tree Species ◽  
Stand Structure ◽  
Temporal Dynamics ◽  
Structural Parameters ◽  
Forest Communities ◽  
Natural Forests ◽  
Tree Species Composition ◽  
Strong Trend ◽  
Long Term Study

The results of a long-term study on the natural forest dynamics of two forest communities on one sample plot within the Białowieża National Park in Poland are presented. The two investigated forest communities consist of the Pino-Quercetum and the Tilio-Carpinetum type with the major tree species Pinus sylvestris, Picea abies, Betula sp., Quercus robur, Tilia cordata and Carpinus betulus. The results reveal strong temporal dynamics of both forest communities since 1936 in terms of tree species composition and of general stand structure. The four major tree species Scots pine, birch, English oak and Norway spruce, which were dominant until 1936, have gradually been replaced by lime and hornbeam. At the same time, the analysis of structural parameters indicates a strong trend towards a homogenization of the vertical stand structure. Possible causes for these dynamics may be changes in sylviculture, climate change and atmospheric deposition. Based on the altered tree species composition it can be concluded that a simple ≪copying≫ (mimicking) of the processes taking place in natural forests may not guarantee the conservation of the multifunctional character of the respective forests.

Effects of nitrogen deposition on nitrate leaching from forests of the northeastern United States will change with tree species composition

2017 ◽  
Vol 47 (8) ◽  
pp. 997-1009 ◽  
Author(s):  
Katherine F. Crowley ◽  
Gary M. Lovett
Keyword(s):  
United States ◽  
Species Composition ◽  
Nitrate Leaching ◽  
Tree Species ◽  
N Deposition ◽  
Red Oak ◽  
Northeastern United States ◽  
Tree Species Composition ◽  
White Ash ◽  
Species Change

As tree species composition in forests of the northeastern United States changes due to invasive forest pests, climate change, or other stressors, the extent to which forests will retain or release N from atmospheric deposition remains uncertain. We used a species-specific, dynamic forest ecosystem model (Spe-CN) to investigate how nitrate (NO3–) leaching may vary among stands dominated by different species, receiving varied atmospheric N inputs, or undergoing species change due to an invasive forest pest (emerald ash borer; EAB). In model simulations, NO3– leaching varied widely among stands dominated by 12 northeastern North American tree species. Nitrate leaching increased with N deposition or forest age, generally with greater magnitude for deciduous (except red oak) than coniferous species. Species with lowest baseline leaching rates (e.g., red spruce, eastern hemlock, red oak) showed threshold responses to N deposition. EAB effects on leaching depended on the species replacing white ash: after 100 years, predicted leaching increased 73% if sugar maple replaced ash but decreased 55% if red oak replaced ash. This analysis suggests that the effects of tree species change on NO3– leaching over time may be large and variable and should be incorporated into predictions of effects of N deposition on leaching from forested landscapes.

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