scholarly journals Predicting population status of gum and resin bearing plant species from size distributions in Benishangul Gumuz Regional State, Ethiopia: Inferences for their sustainable management

2021 ◽  
Vol 1 (1) ◽  
pp. 022-031
Author(s):  
Dereje Mosissa ◽  
Girum Faris ◽  
Sisay Aman
Keyword(s):  
Basal Area ◽  
Woody Species ◽  
Small Scale ◽  
Older Individuals ◽  
Importance Value Index ◽  
Importance Value ◽  
Continuous Growth ◽  
Regeneration Status ◽  
Regional State ◽  
Good Reproduction

Diversity, population structures and regeneration status of gum- and resin- producing woody species, were assessed in 116 sample plots, each measuring 400 m2 and established along line transects. The data were collected in two selected districts, namely, Sherkole and Kurmuk in Benishangul-Gumuz National Regional State, one of the gum and resin belts in western Ethiopia. The gum- and resin-producing woody species had 1.04 and 0.7 diversity and 0.576 and 0.49 evenness values at Kurmuk and Sherkole districts, respectively. They accounted for 26% and 46% of the density, 51% and 58% of the basal area and 32% and 53% of the Importance Value Index of all the woody species, respectively. The gum- and resin- bearing woody species exhibited three patterns of population structure. The first pattern suggests good reproduction abilities of the species coupled with good recruitment of seedlings and their subsequent continuous growth to replace older individuals over time, indicating stable regeneration. About 61% of the gum- and resin- bearing woody species fall under this category. The other two patterns indicate hampered regeneration status of the woody species. Heavy grazing, conversion to crop land by small scale farming, gold mining, recurrent fire and climate change were mentioned as major bottlenecks of natural regeneration and recruitment. Policy, extension and research recommendations are discussed.

scholarly journals Predicting Population Status of Gum and Resin Bearing Plant Species from Size Distributions in Benishangul Gumuz Regional State, Ethiopia: Inferences for Their Sustainable Management

2021 ◽  
pp. 48-55
Author(s):  
Dereje Mosissa ◽  
Girum Faris ◽  
Sisay Aman
Keyword(s):  
Basal Area ◽  
Woody Species ◽  
Small Scale ◽  
Older Individuals ◽  
Importance Value Index ◽  
Importance Value ◽  
Continuous Growth ◽  
Regeneration Status ◽  
Regional State ◽  
Good Reproduction

Diversity, population structures, and regeneration status of gum- and resin-producing woody species, were assessed in 116 sample plots, each measuring 400 m2 and established along line transects. The data were collected in two selected districts, namely, Sherkole and Kurmuk in Benishangul-Gumuz National Regional State, one of the gums and resin belts in western Ethiopia. The gum- and resin-producing woody species had 1.04 and 0.7 diversity and 0.576 and 0.49 evenness values at Kurmuk and Sherkole districts, respectively. They accounted for 26% and 46% of the density, 51% and 58% of the basal area, and 32% and 53% of the Importance Value Index of all the woody species, respectively. The gum- and resin-bearing woody species exhibited three patterns of population structure. The first pattern suggests good reproduction abilities of the species coupled with a good recruitment of seedlings and their subsequent continuous growth to replace older individuals over time, indicating stable regeneration. About 61% of the gum- and resin-bearing woody species fall under this category. The other two patterns indicate the hampered regeneration status of the woody species. Heavy grazing, conversion to cropland by small-scale farming, gold mining, recurrent fire, and climate change were mentioned as major bottlenecks of natural regeneration and recruitment. Policy, extension, and research recommendations are discussed.

scholarly journals An Assessment of Forest Structure, Regeneration Status and the Impact of Human Disturbance in Panchase Protected Forest, Nepal

2020 ◽  
Vol 17 ◽  
pp. 42-66
Author(s):  
Roshan Chikanbanjar ◽  
Binod Baniya ◽  
Man Kumar Dhamala
Keyword(s):  
Human Disturbance ◽  
Human Impacts ◽  
Structural Characteristics ◽  
Basal Area ◽  
Consumption Pattern ◽  
Importance Value Index ◽  
Importance Value ◽  
Regeneration Status ◽  
The Impact ◽  
Fuelwood Consumption

Vegetation study is crucial for the biophysical environment and ecosystem balance. Both qualitative and quantitative assessments of the vegetation can give complete picture of the forest ecosystem. In this study, quantitative characteristics of Panchase Protected Forest in Kaski district were analyzed. The study was focused on the structural characteristics of forest stand, its regeneration pattern along altitudinal gradients, and human impacts on vegetation structure. Density, basal area, frequency, and Importance Value Index (IVI) were used to assess the structural characteristics of forest; Density-Diameter (DD) curve and seedling/sapling/tree density relation were used to assess the regeneration status. Counting the number of lopping and cut stumps and quantifying fuelwood consumption pattern of the village were used to assess human disturbance. The vegetation survey showed 21, 17 and 14 species of trees, saplings, and seedlings, respectively. Daphniphyllum himalense was the most dominant species followed by Quercus lamellosa. DD curve showed reverse J-shaped structure indicating sustainable regeneration. Daphniphyllum himalense and Alnus nepalensis were major species of trees consumed as fuelwood and average annual fuelwood consumption was 2083.79 tons. Density of lopped trees and cut stump was in decreasing trend along with elevation. Species richness was higher in moderately disturbed sites. This study has significant implications for protected forest management and biodiversity conservation in Nepal.

scholarly journals Woody Species Diversity and Structure of Protected Woodlands Adjacent to Free Grazing Land Woodland at Dugda Woreda, Oromia, Ethiopia

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Tsegu Ereso Denbel
Keyword(s):  
Basal Area ◽  
Floristic Composition ◽  
Woody Species ◽  
Systematic Sampling ◽  
Importance Value Index ◽  
Importance Value ◽  
Mature Trees ◽  
Grazing Land ◽  
Individual Tree ◽  
Breast Height

The study was conducted in protected woodland and free graze woodland located in Dugda Woreda, Oromia state, Ethiopia. The objective of the study was to explore the floristic composition, structure, and regeneration of woody species. In the park, the vegetation ecology has not been studied up to date, which is necessary for conservation. The systematic sampling technique was used to collect vegetation and human disturbance (presence and absence) data from August to December 2017. The vegetation data were collected from 30 plots from each woodland with a size of 900 m2 (30 m × 300 m) for tree/shrub, while subplots of size 400 m2 (20 m × 20 m) for sapling, respectively, were established in the main plots. Individual tree and shrub diameters at breast height (DBH) ≥2.5 cm and height ≥ 2 m were measured using a tape meter and clinometer, respectively. Diameter at breast height (DBH), frequency, density, basal area, and importance value index (IVI) were used for vegetation structure description, while the densities of mature trees, sapling, and seedling were used for regeneration. A total of 446 individual stems from free grazed woodland and 641 individual stems from protected woodland with a DBH of ≥2.5 cm were encountered from 30 studied sample plots that are protected and free grazed woodlands. Of these, from the total woody species, 68.42% were trees and 31.57% shrubs found in protected woodland; 76.92% were trees and 23.07% shrubs found in free grazed woodland. The total basal area of the woody plant was 3.1 ± 1 m2/ha in free grazed woodland and 4.2 ± 2 m2/ha in protected woodland, calculated for 19 woody species. Fabaceae, Balanitaceae, Capparidaceae, Verbenaceae, and Boraginaceae families were the most abundant families in both woodlands. However, there is a good initiation for the conservation of the park; still, the vegetation of the park was threatened by human-induced fire following intensive farming, gold mining, and overgrazing.

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 Population status of the tree Sacoglottis holdridgei (Humiriaceae) at Isla del Coco National Park, Costa Rica

2016 ◽  
Vol 64 (1) ◽  
pp. 263
Author(s):  
Luis Guillermo Acosta-Vargas
Keyword(s):  
National Park ◽  
Basal Area ◽  
Forest Monitoring ◽  
Diameter Distribution ◽  
Population Status ◽  
Importance Value Index ◽  
Importance Value ◽  
Data Points ◽  
Using Data ◽  
Annual Mortality

<p>Isla del Coco is the only oceanic island in the Eastern Pacific with humid tropical climate. Its forests have a particular structure with a unique array of plant species and high endemism. There are few studies on the flora or forest monitoring on the island.  The population structure of <em>Sacoglottis holdridgei</em> was analyzed using data from six years with data points taken in 2006 and 2012, including sampling of regeneration in 2012.<em> Sacoglottis holdridgei </em>was the most important tree species, presenting in 2012 the highest Importance Value Index (190.7±21.8), abundance (158.5±40.3 Nha<sup>-1</sup> or 39.5 % of the forest) and basal area (15.6 m<sup>2</sup>ha<sup>-1 </sup>or 72.9 % of the forest). It was present in all three height strata with dominance in the highest. Annual mortality was reported at 3.3 % and recruitment at 1.2 %. The diameter distribution of forest fits the inverted <em>J</em> model, but not for the reported species of which only <em>S. holdridgei</em> tends to adjust for DBH&gt;40 cm. Regeneration fitted the inverted<em> J</em> model with values below those reported for continental forests. Even though it was the dominant species, <em>S. holdridgei </em>showed low regeneration values. This particular condition, give way hypotheses related to the introduction of species, species biology and climate change which could influence the future development of <em>S. holdridgei</em> and forests of Isla del Coco.</p><div> </div>

Structure and floristic composition of a tropical evergreen forest in south-west India

1996 ◽  
Vol 12 (2) ◽  
pp. 191-214 ◽  
Author(s):  
Jean-Pierre Pascal ◽  
Raphael Pelissier
Keyword(s):  
Western Ghats ◽  
Basal Area ◽  
Floristic Composition ◽  
Evergreen Forest ◽  
Systematic Sampling ◽  
Importance Value Index ◽  
Importance Value ◽  
Tropical Evergreen Forest ◽  
Western Ghats Of India ◽  
The Western Ghats

ABSTRACTA permanent plot of 28 ha was established in a dense wet evergreen forest in the Western Ghats of India to study the functioning of the ecosystem. Since April 1990, 1981 trees of ≥30 cm gbh have been enumerated in a systematic sampling of five strips totalling 3.12 ha. This paper describes the main structural and floristic characteristics of the plot.The density (635 trees ≥30 cm gbh per hectare) and basal area (39.7 m2 ha−1) are high. Despite the high diversity (Simpson's D = 0.92 and Shannon's H' = 4.56), four species are distinctly, dominant in terms of an importance value index (relative density + relative basal area). Each of these four species occupies a different layer in the ecosystem: Humboldtia brunonis Wall. (Fabaceae) dominates the undergrowth, Myristica dactyloïdes Gaertn. (Myristicaceae) the intermediate strata, Valeria indica L. (Dipterocarpaceae) the higher canopy level and Dipterocarpus indicus Bedd. (Dipterocarpaceae) the emergents. This pronounced species hierarchy is one of the most important characteristics of the evergreen forests of the Western Ghats. The two dipterocarps account for 20.1% of the total number of trees and contribute 40.9% to the total basal area. This formation can, therefore, be considered as the westernmost lowland dipterocarp forest of Asia.Analysis of the spatial variations in the floristic composition and in the structure of the main species populations shows that two kinds of mature phases can be identified: where the topography is raised and gently sloping, the vertical structure of the stand is discontinuous, with Dipterocarpus indicus and Vateria indica forming an emergent layer above a dense undergrowth; on slopes, the stand is lower, vertically continuous and saturated with Valeria indica and Myristica dactyloïdes. The link between the structure of the stand and dynamic processes is discussed.

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 Structure, composition and tree diversity in a temperate forest under management

2019 ◽  
pp. 29-35
Author(s):  
Antonio Mora-Santacruz ◽  
María Leonor Román-Miranda ◽  
Omar Nungaray-Villalobos ◽  
Gerardo Alberto González-Cueva
Keyword(s):  
Temperate Forest ◽  
Cloud Forest ◽  
Basal Area ◽  
Diversity Indices ◽  
Shannon Index ◽  
Importance Value Index ◽  
Importance Value ◽  
A Value ◽  
Normal Diameter ◽  
Area And Volume

In order to study both diversity indices and structure of forests, which are an essential tool for decision-making in forest management, which show natural successional processes and effects for its management. So the objetive of this study was to evaluate structure and diversity of arboral species in a temperate forest of southern Jalisco state. Five permanent forestry research sites 50 x 50 (2.500 m2) were established, and a census of all tree species was carried out, with normal diameter greater than 7.5 cm. Each individual was measured: height and normal diameter, placing an aluminum plate for identification. We obtained the importance value index (IVI), indices of diversity, richness, and dasometric parameters. There were 17 species, 9 genera and 9 botanical families; the Fagaceae was dominant. Pinus douglasiana presented the highest IVI (57.93%); The Shannon index had a value of 2.0; the index of Margalef was 2.4; the forest has a density of 688 trees ha-1, being the most abundant Styrax ramirezii; Pinus herrerae obtained the highest values in basal area and volume with 30.77 m2 ha-1 and 357,325 m3 ha-1 respectively. The values of diversity are influenced by elements of the cloud forest

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