scholarly journals Factors Influencing Liana Species Richness and Structure following Anthropogenic Disturbance in a Tropical Forest, Ghana

ISRN Forestry ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Patrick Addo-Fordjour ◽  
Philip El Duah ◽  
David Kafui Kudjo Agbesi
Keyword(s):  
Species Richness ◽  
Forest Structure ◽  
Forest Type ◽  
Basal Area ◽  
Forest Tree ◽  
Stepwise Multiple Regression ◽  
Importance Value Index ◽  
Importance Value ◽  
Soil Variables ◽  
Species Richness And Abundance

The study was conducted to determine the factors that influenced liana species richness and structure in forests of different disturbance intensities (high, moderate, and low disturbance forests) in the Southern Scarp Forest Reserve, Ghana. Within each forest, lianas (dbh  cm) were enumerated in six  m2 plots located along transects. Soil physicochemical properties and forest structure were determined within the plots. Liana species richness and abundance were significantly lower in the high disturbance forest () whereas basal area was significantly higher in the low disturbance forest (). Tree abundance and dbh significantly predicted liana species richness and structure in the study (). On the basis of the importance value index, three main liana communities, each corresponding with a forest type, were identified. Stepwise multiple regression analysis revealed that exchangeable magnesium and calcium, and total exchangeable bases were the main soil variables that affected liana species richness. Liana structure was influenced by the above-mentioned soil variables as well as exchangeable potassium and sodium, and pH. The present study has demonstrated that changes in liana species richness and structure following human disturbance may be due to variations in soil properties and forest structure.

scholarly journals How Timber Harvest Affects the Structure and Diversity of a Montane Forest in Southern Mexico

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 895
Author(s):  
Nayely Martínez-Meléndez ◽  
Neptalí Ramírez-Marcial ◽  
Pablo Martínez-Zurimendi ◽  
Manuel J. Cach-Pérez ◽  
José G. García-Franco
Keyword(s):  
Species Richness ◽  
Dominant Species ◽  
Basal Area ◽  
Timber Harvest ◽  
Montane Forest ◽  
Control Treatment ◽  
Importance Value Index ◽  
Importance Value ◽  
Southern Mexico ◽  
Timber Extraction

Timber extraction directly affects forest structure by opening the canopy, reducing the density and volume of dominant species, and transforming the composition, diversity, and functioning of the forest. We analyze the richness, diversity, and basal area of tree species in a pine–oak montane forest under two stages of the Silvicultural Development Method (thinning and liberation cut treatments) in comparison with remnants of forest considered to be control treatment in the Ocotones forest. Timber extraction began 14 years previously but its effect on the tree structure has not been studied to date in this area. We quantified and measured all the trees with a diameter at breast height >5 cm in 12 0.1 ha circular plots in each treatment. Diversity (Hill numbers) and the importance value index were calculated in each treatment. Observed species richness did not differ between treatments; Pinus oocarpa Schiede ex Schltdl. and Quercus sapotifolia Liebm. were the dominant species regardless of treatment. The principal differences in density and basal area among the treatments were found between the small oaks and small pines. In general, tree density recovered in managed areas because of newly recruited pines and re-sprouting oaks. Although no significant reduction in species richness was detected between treatments, species composition and vegetation structure were modified by the extraction of pine timber and the permanence of many large oaks. Silvicultural treatments appear to create conditions favorable to the maintenance of species richness. The silvicultural interventions in the site meet the objectives of timber production, regeneration, and biodiversity conservation; however, the question of how long the forest can maintain its species diversity and structure after timber extraction remains to be addressed.

scholarly journals Floristic composition, diversity and structure of Khaya senegalensis stands in Benue Department, Cameroon

2021 ◽  
Vol 8 (1) ◽  
pp. 60-68
Author(s):  
Awé Djongmo Victor ◽  
Noiha Noumi Valery Valery ◽  
Madou Chantal Chantal ◽  
Zapfack Louis
Keyword(s):  
Species Richness ◽  
Diversity Index ◽  
Basal Area ◽  
Shannon Index ◽  
Simpson Index ◽  
Importance Value Index ◽  
Importance Value ◽  
Acacia Senegal ◽  
Significant Difference ◽  
Khaya Senegalensis

The present work has been done to provide basic data for a better conservation and valorization ofKhaya senegalensis stands in Sudano-Sahelian zone of Cameroon. A 100 m x 50 m transectmethod was undertaken to measure floristic diversity through the use of species richness,Shannon index, Pielou equitability, Simpson index, importance value index and importance valuefamily. The vegetation structure is determined by density, basal area and biovolume. Theinventory included trees with a dbh ?10 cm on an area of 1 ha per plot. A total of 6743individuals distributed in 24 families, 33 genera and 54 species were inventoried in all Khayasenegalensis stands studied. Statistical analysis showed significant differences, Shannon index,Simpson index, Pielou equitability, density, basal area, biovolume, species richness, heights class,diameters class, circumferences class but does not certify a significant difference of importancevalue index among in the villages. The undergrowth of Khaya senegalensis stands is more diverseat Bamé with a Shannon diversity index (ISH=5.87 ± 0.12 bit). The greatest of Pielou equitabilityis observed at Bamé (EQ=0.80 ± 0.01). The largest of Simpson index is recorded at Bamé(D=0.098 ± 0.001). Khaya senegalensis Stands are denser at Bamé (194 ± 3.12 individuals/ha).The basal area and biovolume of Khaya senegalensis stands are very high at Bamé (BA=25.87 ±0.06 m2/ha and Biovolume =15.32 ± 0.012 m3/ha). The species importance value is maximal in allthe studied villages (SIV=300 ± 71.45). The importance value index of species revealed a cleardominance in the undergrowth of Khaya senegalensis stands are Combretum adenogonium;Acacia senegal; Terminalia laxiflora; Guiera senegalensis; Acacia nilotica; Entada Africana.The vertical structure has three aspects, like the L (Dbh), asymmetric (height) and dissymmetrical(circumference) structures attesting to a strong regeneration of the understory ligneous woods ofKhaya senegalensis stands studied.

scholarly journals Assessment of tree diversity in distinctive deciduous forests of Suruli falls, Southern Western Ghats

2018 ◽  
Vol 10 (4) ◽  
pp. 1085-1093
Author(s):  
J Naveenkumar ◽  
Somaiah Sundarapandian
Keyword(s):  
Species Richness ◽  
Western Ghats ◽  
Deciduous Forest ◽  
Basal Area ◽  
Deciduous Forests ◽  
Stem Density ◽  
Diameter Class ◽  
Importance Value Index ◽  
Importance Value ◽  
Southern Western Ghats

A quantitative inventory was conducted in two distinctive tropical deciduous forests at Suruli falls forest of southern Western Ghats.  Two one-hectare plots were established and all trees >10cm DBH measured. Species richness, density, family importance value (FIV) and importance value index (IVI) were calculated and the results varied among the two sites. A total of 777 stems and 52 species were documented in both the sites and moist deciduous forest (MDF) had maximum number species richness and density than dry deciduous forest (DDF). The basal area was higher in MDF (502 stems/ha and 16.52 m2/ha) than in DDF (275 stems/ha and 7.23 m2/ha). However, Shannon and evenness indices showed a negative trend (DDF- 2.62, 0.41 and MDF- 2.37, 0.27). Diameter class-wise distribution of trees showed reverse ‘J shaped’ curve in both the forest types. Pterocarpus marsupium was the mono-dominant species holding one-third of the IVI (113), 27% of the stem density and 30% of the total basal area. DDF site is suspected to recurrence of annual fire. Anogeissus latifolia and Strychnos potatorum were the fire-tolerant species only found in lower diameter class. The maximum species shared contiguous distribution in the deciduous forests. The observed variations in the tree community between the two deciduous forest sites are possibly due to variations in altitude, rainfall, temperature, past disturbance, fire and edaphic characteristics.

scholarly journals Struktur Floristik Hutan di Kawasan Lindung Sempadan Sungai dalam Areal Hutan Tanaman Industri

2018 ◽  
Vol 10 (1) ◽  
pp. 24
Author(s):  
Nurul Qomar ◽  
Bahdarsyah Bahdarsyah ◽  
P Agung Nugroho ◽  
Rahmi A Rohaini ◽  
Ahmad Muhammad
Keyword(s):  
Species Richness ◽  
Forest Type ◽  
Diversity Index ◽  
Acacia Mangium ◽  
Basal Area ◽  
Pole Density ◽  
Natural Forests ◽  
Conservation Areas ◽  
Importance Value ◽  
Swamp Forest

This study was carried out in riparian conservation forests within a monospecific pulpwood estate in Sorek,Pelalawan District, Riau. The remaining natural forests comprised lowland rainforest (at Sei Buluh and Tolamriversides), mixed swamp forest (at Telayap riverside), and pole forest (at Rangsang riverside). The objective of thecurrent study was to describe the floristic structure of each forest type at the conservation areas in concern.Fifteen transects (width of 20 m) were established at all sites with a total length of 8.080 m. Quadrates plots of 20x 20 m were established with continue on these transect for tree sampling (dbh > 20 cm) and smaller quadrates(10 x 10 m) were nested on each one of the former for pole sampling (dbh 10 – 20 cm). The parameters used in thisstudy were Importance Value (IV), species richness (Margalef Index = R1 and Menhinick Index = R2), and Diversity Index (Shannon = H’ and Simpson = D). Results showed that in tree stratum, the largest basal area (11.25 m2ha-1) and the highest diversity was found at Telayap’s riverside (H’ = 3.70 and D = 0.98). Species richness was most profound at Tolam riverside (R1 = 10.43 and R2 = 2.83). Rangsang’s riverside possessed the highest tree density (105 individuals ha-1) but with the smallest dbh (26.5 cm). This forest was a peat-swamp forest predominating by bintangur (Calophyllum pulcherimum). At the pole stratum, the largest basal area (7.00 m2ha-1) and the highest diversity was found at Tolam riverside (H’ = 3.39 and D = 0.96). Species richness was most profound at Telayap’s riverside (R1 = 8.89 and R2 = 2.64). The highest pole density (380 individuals ha-1) was observed at Sei Buluh’s riverside, in which mempening (Quercus lucida Roxb.) was predominating. Acacia mangium was establishing very well at all sites, indicating its adaptability and potentially invasive feature.

scholarly journals Forest Structure, Composition and Above Ground Biomass of Tree Community in Tropical Dry Forests of Eastern Ghats, India

2016 ◽  
Vol 8 (1) ◽  
pp. 125-133 ◽  
Author(s):  
Sudam Charan SAHU ◽  
H.S. SURESH ◽  
N.H. RAVINDRANATH
Keyword(s):  
Forest Structure ◽  
Tree Species ◽  
Basal Area ◽  
Eastern Ghats ◽  
Tropical Dry Forests ◽  
Above Ground Biomass ◽  
Importance Value ◽  
Shorea Robusta ◽  
Ground Biomass ◽  
C Stocks

The study of biomass, structure and composition of tropical forests implies also the investigation of forest productivity, protection of biodiversity and removal of CO2 from the atmosphere via C-stocks. The hereby study aimed at understanding the forest structure, composition and above ground biomass (AGB) of tropical dry deciduous forests of Eastern Ghats, India, where as a total of 128 sample plots (20 x 20 meters) were laid. The study showed the presence of 71 tree species belonging to 57 genera and 30 families. Dominant tree species was Shorea robusta with an importance value index (IVI) of 40.72, while Combretaceae had the highest family importance value (FIV) of 39.01. Mean stand density was 479 trees ha-1 and a basal area of 15.20 m2 ha-1. Shannon’s diversity index was 2.01 ± 0.22 and Simpson’s index was 0.85 ± 0.03. About 54% individuals were in the size between 10 and 20 cm DBH, indicating growing forests. Mean above ground biomass value was 98.87 ± 68.8 Mg ha-1. Some of the dominant species that contributed to above ground biomass were Shorea robusta (17.2%), Madhuca indica (7.9%), Mangifera indica (6.9%), Terminalia alata (6.9%) and Diospyros melanoxylon (4.4%), warranting extra efforts for their conservation. The results suggested that C-stocks of tropical dry forests can be enhanced by in-situ conserving the high C-density species and also by selecting these species for afforestation and stand improvement programs. Correlations were computed to understand the relationship between above ground biomass, diversity indices, density and basal area, which may be helpful for implementation of REDD+ (reduce emissions from deforestation and forest degradation, and foster conservation, sustainable management of forests and enhancement of forest carbon stocks) scheme.

Conservation value of koa (Acacia koa) reforestation areas on Hawaii Island

2018 ◽  
Vol 24 (1) ◽  
pp. 35
Author(s):  
Laurie Strommer ◽  
Sheila Conant
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Native Species ◽  
Canopy Cover ◽  
Basal Area ◽  
Forest Tree ◽  
Native Forest ◽  
Acacia Koa ◽  
Total Species Richness ◽  
Hawaii Island

Efforts to restore forests for ecological and economic benefit in Hawaii are converging on koa (Acacia koa), an endemic dominant or codominant canopy tree common across broad elevation and moisture gradients. We quantified plant species composition and forest structure in koa reforestation areas (KRAs) and in nearby intact native forest on Hawaii Island. Total species richness and percentage native species richness were lower in the plantation forests than in the intact forests, although species richness in the KRAs at one site was not significantly different from that in intact forest. Tree, sapling, and seedling densities differed between KRAs and forest sites at one site. At another, the native forest and one KRA had similar tree and seedling densities and similar canopy height and percentage canopy cover. Total stand basal area was greatest in the intact forest at both sites, although the basal area for the KRAs at one site exceeded those for intact forest at the other. Koa plantings can be structurally similar to intact forests though species composition differs. Our results suggest that koa forestry can facilitate native understorey development in some cases.

scholarly journals Vascular Epiphytic Diversity in a Neotropical Transition Zone Is Driven by Environmental and Structural Heterogeneity

2019 ◽  
Vol 12 ◽  
pp. 194008291988220 ◽  
Author(s):  
Edilia de la Rosa-Manzano ◽  
Glenda Mendieta-Leiva ◽  
Antonio Guerra-Pérez ◽  
Karla María Aguilar-Dorantes ◽  
Leonardo Uriel Arellano-Méndez ◽  
...  
Keyword(s):  
Species Richness ◽  
Transition Zone ◽  
Forest Structure ◽  
Forest Type ◽  
Species Turnover ◽  
Cloud Forest ◽  
Size Variation ◽  
Alpha Diversity ◽  
Forest Types ◽  
Semideciduous Forest

Vascular epiphytes contribute significantly to tropical diversity. Research on the factors that determine vascular epiphytic diversity and composition in tropical areas is flourishing. However, these factors are entirely unknown in tropical-temperate transition zones, which represent the distribution limit of several epiphytic species. We assessed the degree to which climatic and structural variables determine the diversity of vascular epiphytic assemblages (VEAs) in a transition zone in Mexico: the El Cielo Biosphere Reserve. We found 12,103 epiphytic individuals belonging to 30 species and 15 genera along a climatic gradient from 300 to 2,000 m a.s.l. Bromeliaceae and Orchidaceae were the most species-rich families. Forests along the windward slope of the Sierra Madre Oriental (semideciduous forest and tropical montane cloud forest) had higher species richness than forests along the leeward slope (pine-oak forest and submontane scrub). Species richness was largely determined by seasonality and, to a lesser degree, by forest structure, whereas abundance was mainly determined by host tree size. Variation in VEAs composition was largely explained by climatic variables, whereas forest structure was not as important. VEAs differed among forest types and slopes in terms of taxonomic and functional composition. For example, certain bromeliad indicator species reflected differences between slopes. Although within-tree epiphytic species richness (alpha diversity) was low in this transition zone relative to other habitats, species turnover among forest types (beta diversity) was high. These findings suggest that each forest type makes a unique and important contribution to epiphytic diversity in this transition zone.

scholarly journals Fuel beds variation of coastal tropical freshwater forested wetlands in three disturbance regimes at La Encrucijada, Biosphere Reserve, Mexico

2020 ◽  
Author(s):  
Romeo de Jesús Barrios Calderón ◽  
Dulce Infante Mata ◽  
José Germán Flores Garnica ◽  
Jony Ramiro Torres Velázquez ◽  
Zulia Mayari Sánchez-Mejía ◽  
...  
Keyword(s):  
Forest Fires ◽  
Biosphere Reserve ◽  
Basal Area ◽  
Forested Wetlands ◽  
Material Surface ◽  
Importance Value Index ◽  
Importance Value ◽  
High Accumulation ◽  
Horizontal Structure ◽  
Tropical Freshwater

Abstract Background: Tropical freshwater forested wetlands in coastal regions are rapidly disappearing, one of the causes is forest fires. This is caused by high accumulation of fuel beds that can vary in origin and type. Therefore, the objective of this study was to characterize the fuel beds in tropical freshwater forested wetlands with three different level of disturbance at El Castaño, La Encrucijada Biosphere Reserve.Methods: Seventeen sampling units were used to described the strates of forest fuel beds (canopy, sub-canopy and understory) in both the vertical and horizontal stratum. Quantity and quality of dead (fallen woody material, surface litterfall and fermented litterfall) fuels were characterized using the planars intersections technique.Results: A total of eight tree species, two shrubs, five lianas and two herbaceous species were found in tropical freshwater forested wetlands. The vertical structure concentrates the highest proportion of trees between 2 and 12 m high, including the first two defined height classes. The horizontal structure denotes a higher percentage of trees with a normal diameter between 2.5 to 7.5 cm (61.4%) of the total. The sites none disturbance presented the highest arboreal density (2,686 ind. ha− 1), however the highest basal area was found in the sites with medium disturbance (39.41 m2 ha− 1). The richness and diversity of species shows that the Fisher, Margalef, Shannon and Simpson α indices were higher in the sites undisturbed, while the Berger-Parker index shows greater dominance in the sites high disturbance. Pachira aquatica Aubl. was the species with the highest importance value index, and contributes the most to the fuel beds. The average accumulation of dead fuel beds was higher in sites with high disturbance (222.18 ± 33.62 t ha− 1), with the largest accumulations of woody fuels occurring in the 1 h, 10 h and 1000 h classes, the latter in a state of fermentation.Conclusions: It’s important to consider the probability of occurrence of surface fires is high. In these tropical freshwater forested wetlands, independent of disturbance, underground fires have the same probability and the intensity will depend on the depth of the organic matter layer. This study contributes define fire-prone areas in these ecosystems. The results are of great importance to design fire prevention strategies.

scholarly journals Comparison of true mangrove stands in Dudepo and Ponelo Islands, North Gorontalo District, Indonesia

2018 ◽  
Vol 20 (1) ◽  
pp. 259-266
Author(s):  
FAIZAL KASIM ◽  
MIFTAHUL KHAIR KADIM ◽  
SITTI NURSINAR ◽  
ZULKIFLI KARIM ◽  
ALDIN LAMALANGO
Keyword(s):  
Similarity Index ◽  
Basal Area ◽  
Current Status ◽  
Survey Method ◽  
Landsat 8 ◽  
Importance Value Index ◽  
Importance Value ◽  
Mangrove Species ◽  
Rhizophora Apiculata ◽  
The Mean

Kasim F, Kadim MK, Nursinar S, Karim Z, Lamalango A. 2019. Comparison of true mangrove stands in Dudepo and Ponelo Islands, North Gorontalo District, Indonesia. Biodiversitas 20: 259-266. This study aimed to investigate and compare the current status of mangrove areas, as well as the composition and species diversity of mangrove stands in both regions of Dudepo and Ponelo Islands. The results showed that the mangrove areas calculated using the segmentation method in classifying image of Landsat-8 OLI (acquisition on September 2017) were 279.46 ha (Dudepo Island) and 113.35 ha (Ponelo Island) respectively. A total of 13 species of true mangrove were recorded from both islands, using survey method from 9 transect lines (TL), with a distance ranging from 40 to 210 meters (1-6 quadrats) per transect. The mean densities of trees were 2133 ± 329.78 ha-1 (Dudepo Island) and 2111 ± 234.28 ha-1 (Ponelo Island), while those of saplings and seedlings were 58 ± 13.48 ha-1 and 1425 ± 113.96 ha-1 (Dudepo Island), and 79 ± 14.51 ha-1 and 2963 ± 443.22 ha-1 (Ponelo Island). The mean diameter and basal area were 19.73 ± 10.65 cm and 84.22 ± 67.67 m2ha-1 (Dudepo Island), 17.04 ± 1.46 cm and 60.07 ± 15.12 m2ha-1 (Ponelo Island), respectively. The Importance Value Index (IVI) ranged between 3.97-114.87 (Dudepo Island) and 6.04-82.18 (Ponelo Island). The dominant and codominant species based on IVI in both islands were Rhizophora apiculata Blume and R. stylosa Griff. The indexes of diversity, richness, and evenness of mangrove species in both islands were 0.34-1.70, 0.48-1.18, 0.47-0.94 (trees), 0.00-1.10, 0.00-1.82, 0.00-1.00 (saplings), and 0.00.-1.48, 0.00-1.44, 0.72-1.00 (seedlings), respectively. The Bray-Curtis similarity index between Dudepo and Ponelo Islands, based on the overall values of community attributes, was 0.75.

scholarly journals Tree reproductive phenology determines the abundance of medium–sized and large mammalian assemblages in the Guyana shield of the Brazilian Amazonia

2020 ◽  
pp. 9-26 ◽  
Author(s):  
A. R. Mendes Pontes ◽  
V. M. Guedes Layme ◽  
L. R. Rodrigues de Lucena ◽  
D. J. Chivers
Keyword(s):  
Tree Species ◽  
Forest Type ◽  
Mammalian Species ◽  
Basal Area ◽  
Stepwise Multiple Regression ◽  
Reproductive Phenology ◽  
Line Transect ◽  
Forest Types ◽  
Brazilian Amazonia ◽  
Habitat Variables

Assemblages of medium and large–sized mammals were studied in the Guyana shield of the Brazilian Amazonia. Diurnal and nocturnal line–transect samplings were carried out via the line–transect method in five different forest types along a 10–km transect, along which we also recorded habitat variables, such as tree species diversity, reproductive phenology, and residual fruit productivity. Group density was separately calculated for all mammalian species in the five forest types. Stepwise multiple regression analyses were performed to determine which habitat variables best predicted the mammalian species densities in the sampled forests. The sole determinants of mammalian densities in the forest types studied were basal area of each forest type, total number of tree species in each forest type, and tree reproductive phenology.

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