Dynamics of the forest vegetation of the Umtiza Nature Reserve, East London

Bothalia ◽  
1993 ◽  
Vol 23 (1) ◽  
pp. 111-116 ◽  
Author(s):  
J. J. Midgley ◽  
P. N. Gobetz
Keyword(s):  
Nature Reserve ◽  
Multivariate Analyses ◽  
Woody Species ◽  
Size Class ◽  
Forest Community ◽  
Species Occurrence ◽  
Importance Value ◽  
Fine Grained ◽  
Afromontane Forests ◽  
Canopy Species

The forest community at the Umtiza Nature Reserve near East London was surveyed using 24 plots (0.04 ha) in which all woody stems 0.5 m tall were enumerated. Based on a classification using numbers of stems of canopy species, it was assumed that basically only one forest community was sampled. Further multivariate analyses suggest that this forest is fine-grained. Sample plots were similarly placed in ordination space irrespective of whether woody species occurrence was used as importance value or if species occurrence per size class was used separately [seedlings (0.5-1.0 m), saplings (1-5 m) or canopy individuals ( 5 m)). An analysis of size-class distributions of the most common canopy species indicated that the majority of species exhibited inverse J-shaped size-class distributions. This is the expected pattern for a fine-grained forest. In these measures of dynamics, this forest is not fundamentally different to the more temperate Afromontane forests.

scholarly journals Assessment of species diversity and distribution of woody species on selected plots in Olokemeji Forest Reserve, Ogun State, Nigeria

2021 ◽  
Vol 22 (3) ◽  
pp. 43-50
Author(s):  
D.M. Taiwo ◽  
S.I. Udoh ◽  
S.O. Olaoti-Laaro ◽  
O.R. Jeminiwa ◽  
M.S. Jeminiwa
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Woody Species ◽  
Tectona Grandis ◽  
Importance Value ◽  
Forest Reserve ◽  
Lowland Rain Forest ◽  
Ogun State ◽  
The Status ◽  
And Function

The Assessment of forest species composition and species diversity is essential in understanding the status of tree population and diversity for conservation purpose. Olokemeji forest reserve is situated in the lowland rain  forest of south-western Nigeria and it occupies a total land area of 58.88 km2 . Six study plots of 50m2 each were randomly selected and designated as Frequently Burnt Plot 1, Frequently Burnt Plot 2, Harvested Plot, Unharvested Unburnt Plot, Arable Plot 1 and Arable Plot 2 for the purpose of assessment of species diversity and distribution of woody species. Seven species of trees were identified belonging to five families. One hundred and eighty two stands were enumerated, with Unharvested Unburnt Plot having the highest number of trees at 50. The dominance index for the woody flora was 1 in Frequently Burnt Plot 1 and 2 as well as Arable Plot 1 and 2 except for the Harvested Plot that had the lowest (0.29) while the Unharvested Unburnt Plot had 0.75. Highest species richness was recorded at the Harvested Plot at 0.71. The species diversity in Harvested Plot was low (1.54), while it was extremely low in Unharvested Unburnt Plot (0.43). Evenness index was lowest in the Unharvested Unburnt Plot at 0.43. Tectona grandis had the highest relative importance value in the Frequently Burnt Plot 1. The low species richness and species diversity is a direct indication of anthropogenic interference in the study plots and the forest reserve; this requires urgent mitigation to prevent a total loss of its structure and function as expected of a forest reserve. Keywords: Species, Diversity, Evenness, Anthropogenic, Forest, Dynamics

scholarly journals Woody species diversity from proposed ecologically sensitive area of northern Western Ghats: implications for biodiversity management

2020 ◽  
Vol 12 (9) ◽  
pp. 16048-16063
Author(s):  
M. Tadwalkar ◽  
A. Joglekar ◽  
Monali Mhaskar ◽  
A. Patwardhan
Keyword(s):  
Species Diversity ◽  
Tropical Forests ◽  
Western Ghats ◽  
Stand Structure ◽  
Woody Species ◽  
Importance Value ◽  
Threatened Plant Species ◽  
Western Ghats Of India ◽  
Woody Species Diversity ◽  
The Western Ghats

The Western Ghats of India support an array of tropical forests ranging from wet evergreen to scrub formations.  Several endemic and threatened plant species are located in areas other than protected areas (PAs).  There is an urgent need to understand species diversity in areas other than PAs, for effective management of tropical forests.  In this context, reserve forests and informal PAs of Amboli from northern Western Ghats have been investigated. Woody species composition, diversity, and stand structure were assessed by laying quadrats and transects (n=46, area=2.575ha) in closed and open canopy forest patches covering habitat heterogeneity and environmental gradient of the area. A total of 2,224 individuals (of 87 species, 68 genera, and 35 families) was enumerated.  Memecylon umbellatum, Syzygium cumini, and Diospyros nigrescens were found to be the most dominant species as per importance value index.  Melastomataceae was the most dominant family as per family importance value, whereas Euphorbiaceae and Rutaceae were the most speciose.  Fourteen IUCN Red List assessed species and 18 species endemic to the Western Ghats were encountered.  Endemic species accounted for nearly 20% of the total number of individuals sampled.  Demographic profile exhibited reverse ‘J’ pattern.  Average basal area was 27.02m2 per hectare. Woody species diversity of Amboli forests was found comparable with other PAs from northern Western Ghats.  Amboli and the adjoining area have been proposed as ecologically sensitive and in the wake of anthropogenic and developmental pressures they experience, it calls for urgent conservation attention.

scholarly journals The Alien Fraction of the Woody Flora of Yelanetskyi Step Nature Reserve, Southern Ukraine

2020 ◽  
Vol 39 (4) ◽  
pp. 322-332
Author(s):  
Valeriia O. Konaikova ◽  
Olena V. Vakarenko
Keyword(s):  
Alien Species ◽  
Protected Area ◽  
Nature Reserve ◽  
Robinia Pseudoacacia ◽  
Ecological Factors ◽  
Woody Species ◽  
Carbonate Content ◽  
Steppe Communities ◽  
Trees And Shrubs ◽  
Southern Ukraine

AbstractResults of investigations on the patterns of distribution and dispersal of alien species of trees and shrubs in the territory of a steppe protected area, Yelanetskyi Step Nature Reserve (Mykolaiv Region, southern Ukraine), are presented. We registered within this protected area 10 alien woody species. For the most widespread ones (Ulmus pumila L., Gleditsia triacanthos L., Elaeagnus angustifolia L., Robinia pseudoacacia L.), we carried out ecological analyses. In order to establish the scope of impact of ecological factors upon these species, their specificity, and interdependence between ecological factors, the phytoindication method was applied (Didukh, 2012). The results of our analysis conducted on 12 main ecological factors (as outlined by Didukh, 2011), such as soil water regime (Hd), variability of damping (Fh), soil aeration (Ae), soil acidity (Rc), nitrogen content (Nt), salt regime (Sl), carbonate content in soil (Ca), thermoregime (Tm), climate humidity (Om), continentality (Kn), cryoregime (Cr), and light intensity (Lc), show that dispersal of model alien species does not have ecological limitation. However, E.angustifolia and R.pseudoacacia have the strongest capacity to penetrate the steppe communities, especially disturbed ones. Further dispersal of these alien species in the studied area and adjacent territories is hampered only by the integrity of the structure of steppe communities.

scholarly journals Woody Species Composition Analysis of Shawo Sacred Forest, Ethiopia

2019 ◽  
Vol 7 (1) ◽  
pp. 12-21
Author(s):  
Alemayehu Haiemicael Mezgebe ◽  
Alemayehu Hailemicael Mezgebe
Keyword(s):  
Species Composition ◽  
Plant Species ◽  
Basal Area ◽  
Woody Species ◽  
Indigenous Communities ◽  
Forest Community ◽  
Systematic Sampling ◽  
Composition Analysis ◽  
Sacred Forest ◽  
Syzygium Guineense

In sacred forests of indigenous communities, landscapes are deemed sacred and are protected through social norms and spiritual values. The main objective of this study was to analyze the woody species composition of Shawo forest and explore the traditional governing systems that safeguard the sacred forest up to the present. Systematic sampling method was used to collect data. Accordingly, 42 quadrats each with 400 m2 (20 m X 20 m)  was laid along the 14 transect lines. All woody plant species were collected and identified in each of these quadrats. Vegetation parameters such as DBH an Height of each quadrat were recorded. Interview and group discussion were held with local community to gather socio-cultural information. From the result,  16 plant species were found. The average plant density was  499 individual ha-1 with  DBH and H value of  9.21 cm and 10.43 m respecitively.. The  maximum mean plant height was 39.43 m (Syzygium guineense).The total basal area of all plant species was found to be 56.1 m2.ha-1. From the total plant species of Shawo forest Syzygium guineense has the largest basal area 35.77 m2.ha-1 (63.77%) occurring in all 42 plots. The most important plant species of Shawo forest was Syzygium guineense with important value index (IVI) of 151.7 contributing to  50.57% of  total IVI. For future sustainability of Shawo forest, community traditional conservation practices should be appreciated and supported.

Feeding ecology of Portunus pelagicus (Linnaeus, 1758) (Brachyura, Portunidae) in the southern Gulf of Thailand: influences of habitat, season, size class, shell stage and ovigerous condition

Crustaceana ◽  
2015 ◽  
Vol 88 (10-11) ◽  
pp. 1163-1180 ◽  
Author(s):  
Sukree Hajisamae ◽  
Hisam Fazrul ◽  
Siriporn Pradit
Keyword(s):  
Multivariate Analyses ◽  
Feeding Habits ◽  
Size Class ◽  
Stomach Fullness ◽  
Portunus Pelagicus ◽  
Food Items ◽  
Food Packages ◽  
Animal Remains ◽  
Wide Range ◽  
The Impact

The aim of this study is to simultaneously evaluate the impact of ecological and biological conditions on feeding habits of Portunus pelagicus (Linnaeus, 1758). Samples were collected from May 2013 to September 2014 using gill nets. Four moulting stages, three berried stages and four size classes were distinguished in the material collected. It was found that P. pelagicus is omnivorous, feeding on a wide range of benthic invertebrates, scavenging on dead pelagic animal remains, and ingesting significant amounts of plant material. Seasonally, no difference in the stomach fullness index was observed (), but there was a difference in the average number of items (). Both stomach fullness and average number of food items differed between habitats (). Results from multivariate analyses indicated that the diets of P. pelagicus did not change with season but did vary with habitat. Crabs with different biological conditions ingested different food packages. This finding helps in understanding how P. pelagicus copes with different ecological and biological conditions in ingesting its preferred food (under the circumstances).

scholarly journals “Diminishing Returns” in the Scaling between Leaf Area and Twig Size in Three Forest Communities Along an Elevation Gradient of Wuyi Mountain, China

Forests ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1138 ◽  
Author(s):  
Guojie Zhu ◽  
Karl Joseph Niklas ◽  
Man Li ◽  
Jun Sun ◽  
Min Lyu ◽  
...  
Keyword(s):  
Elevation Gradient ◽  
Woody Species ◽  
Forest Community ◽  
Scaling Exponent ◽  
Mass Scaling ◽  
Individual Leaf ◽  
Diminishing Returns ◽  
Leaf Level ◽  
Community Types ◽  
The Individual

Background and aims: The “diminishing returns” hypothesis postulates that the scaling exponent governing the lamina area versus lamina mass scaling relationships has, on average, a numerical value less than one. Theoretically, a similar scaling relationship may exist at the twig level. However, this possibility has not been explored empirically. Methods: We tested both hypotheses by measuring the lamina area and mass, petiole mass of individual leaves, and the total foliage area and stem mass of individual current-year shoots (twigs) of 64 woody species growing in three characteristic forest community types: (1) Evergreen broad-leaved, (2) mixed coniferous and broad-leaved, and (3) deciduous. Key results: The results demonstrate that lamina area vs. mass and lamina area vs. petiole mass differ significantly among the three forest types at both the individual leaf and twig levels. Nevertheless, the scaling exponents of lamina area vs. mass were <1.0 in each of the three community types, as were the corresponding exponents for lamina area vs. petiole mass, both within and across the three community types. Similar trends were observed at the individual twig level. The numerical values of the scaling exponent for lamina area vs. petiole mass and total foliage area vs. stem mass per twig decreased with increased elevation. Conclusions: These data support the “diminishing returns” hypothesis at both the individual leaf level and at the individual twig level, phenomena that can inform future inquiries into the mechanistic basis of biomass allocation patterns to physiological (leaf) and mechanical (stem) plant organs.

An analysis of elm (Ulmus americana) mortality in a second-growth hardwood forest in southeastern Michigan

1976 ◽  
Vol 54 (10) ◽  
pp. 1120-1125 ◽  
Author(s):  
Curtis J. Richardson ◽  
Charles W. Cares
Keyword(s):  
Acer Rubrum ◽  
Dutch Elm Disease ◽  
Forest Community ◽  
Reproductive Capacity ◽  
Hardwood Forest ◽  
Importance Value ◽  
Ulmus Americana ◽  
Important Species ◽  
Quercus Macrocarpa ◽  
Second Growth

A second-growth hardwood forest containing both wet lowland and mesic upland sites in southeastern Michigan was studied 24 years after the introduction of Dutch elm disease. American elm (Ulmus americana) surprisingly had the highest importance value (IV = 61/300) (IV = relative density + relative dominance + relative frequency). Two other species (Acer rubrum and Quercus macrocarpa) closely followed elm with IVs of 41/300 and 38/300. respectively. Mortality for all trees surveyed was 20.4%. Elm comprised 86.6% of this total. Although reduced, the present IV for elm and the percentage of living individuals in each diameter class indicate that elm is still an important species in the forest community. Elm mortality reached 100% only on the poorly drained lowland pockets where densities of elm exceeded 50%. Its high reproductive capacity and dispersal rate indicate that elm will continue to exist as an important species, even if not a canopy dominant, in some types of hardwood communities.

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