Plant Biology and Biodiversity Management

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Browsing Plant Biology and Biodiversity Management by Subject "Abundance"

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    Distribution of Grazing Ungulates in Relation to Water Holes, its Consequence on Soil and Vegetation in the Serengeti Plains, Tanzania
    (Addis Ababa University, 2005-06) Boay Martina; Bekele Afework (Professor)
    The distribution and abundance of grazers in relation to the water holes in the Serengeti plains were studied. Ten species of grazing ungulates were recorded in the area. Using direct and indirect count methods, high abundance of animals was found in zone 1 (areas around water holes). During the dry season, high abundance of Thomson´s gazelle was recorded in burnt areas away from the water hole. In unburnt area, they were abundant closer to the water holes. Total grass cover (percentage), species diversity and grass height were significantly lower in areas around the water holes compared to areas away from the water holes. Grazing was more intense in areas around water holes compared to areas farther. Among soil texture types, only clay fraction shows significant difference among the three zones compared. The percentage of clay in areas near the water hole was high compared to areas away. Soil organic matter, total nitrogen and potassium were significantly lower in areas closer to the water holes, whereas, ammonium, electrical conductivity and pH were significantly higher in areas close to the water holes and decrease with increased distances from the water holes. Most of the smaller grazing ungulates were abundant in burnt areas and in areas with short grasses. The study concluded that the distance from the water hole, fire and rainfall influenced the distribution and abundance of grazing ungulates. Further study should be conducted which can include the long rainy season so as to find out seasonal effects. Key words: Abundance, burnt areas, distribution of grazing ungulates, Serengeti plains, water holes.
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    The Diversity and Abundance of Amphibians in Meru National Park, Kenya
    (Addis Ababa University, 2003-06) Victor Domnick; Bekele Afework (Professor)
    A study on the diversity and abundance of amphibians was conducted in Meru National Park (Kenya) from October 2002 to January 2003. Transect sampling, drift-fence and pitfall trapping as well as opportunistic collections were used to detect amphibians. A total of 430 individuals of amphibians comprising eleven species and six families were observed. Amphibian species diversity was correlated with plant species cover/abundance in three vegetation communities. Acacia wooded grassland had the highest amphibian species diversity (H’ = 2.071, D = 6.74). Acacia-Commiphora bushland ranked second (H’ = 1.858, D = 5.88) while Combretum wooded grassland had the least diversity (H’ = 1.581, D = 5.076). The Acacia wooded grassland had the highest abundance (173 individuals) as well as species richness (10 species). Combretum wooded grassland had eight species (113 individuals) while the Acacia-Commiphora bushland had seven species (144 individuals). Differences in sex ratios within and between vegetation communities were not statistically significant (ANOVA, F = 8.3026, P = 0.6914). No differences were detected on a species by species basis (X2 Test). There was positive linear correlation between amphibian species diversity and plant species diversity in all vegetation communities. Hemisus marmoratus and Phrynomantis bifasciatus were exclusively recorded in the Acacia wooded grassland. Five plant species assemblages were identified from DCA ordination. These closely matched the three broad vegetation communities known for the park. There was least habitat disturbance in the Acacia wooded grassland and a high probability of disturbance in the Combretum wooded grassland. The study confirmed earlier reports that amphibian diversity and abundance can vary on a very small spatial scale. Impacts of habitat disturbance were also demonstrated. The need for long term monitoring of the amphibian population in Meru National Park, by considering additional environmental parameters and introducing a new fire management policy for the park is recommended. Key words: Diversity, Abundance, Amphibians, Meru (Kenya).
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    Diversity and Relative Abundance of Birds in Six Selected Church Forests Located in Addis Ababa
    (Addis Ababa University, 2016-08) Adera, Tebekew; Wube, Tilaye (PhD)
    A survey of birds’ species diversity and abundance was conducted from October to April, 2016. The method used for the study was the Time-spaced point count method. The survey was conducted in six selected church forests of Addis Ababa: Aboye, Asco-Gabriel, Philipos, Petros We-Paulos, Addisu Michael and Amanuel Cathedral. The study was carried out 6 days per month in October, December, and February, and 8 days per month in April. A total of 100 field hours equally distributed in 3 months (October, December, and February) and 28 hours in April were used during the survey. Twenty one species, which belonged to 5 Orders and 17 Families, were recorded. The most common species was common grey-headed sparrow (Passer griseus) and the least common species was Mountain thrush (Turdus abyssinicus).The overall diversity index was (H: 2.70) and evenness value was 0.88. All of the churches have the same number of species; twenty one each. This could be due to proximity of the churches to each other in location. Similarly, the diversity and evenness indices of the churches did not show noticeable variation. The highest diversity and evenness indices were (H: 2.70) and (E: 0.89), respectively; and the lowest diversity and evenness indices were (H: 2.67) and (E: 0.88), respectively. It is recommended that conservation of church forests by all concerned bodies should be practiced since the churches are suitable habitats and refuge for a diverse group of avifauna. Since those small patches play an important role in biodiversity conservation and these natural holy places are maintained through traditional methods of community based conservation that do not require governmental involvements, incorporating these sites into conservation networks could enhance the effectiveness of protected areas by covering a wider variety of habitats and by harnessing the support of local people. Key words: Abundance, birds, biodiversity, churches, Addis Ababa
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    Diversity of Medicinal Plants and Uses in Sayint District South Wollo Amhara Region Ethiopia
    (Addis Ababa University, 2021-10-20) Shiferie, Sintayehu; Warkineh, Bikila (PhD)
    Study of diversity of medicinal plants and uses were conducted in Sayint district, South Wollo, Amhara region, Ethiopia. Data on medicinal plants were collected from 92 informants (53 male and 39 female). Data were collected through questionnaire, interview, market survey, field observation and group discussion. Data were analyzed quantitatively and qualitatively. A total of 75 medicinal plant species were identified and from natural vegetation 61 (81%) and home garden 14 (19 %) distributed in 68 genera and 42families. The abundance of medicinal plants was categorized as presently safe (40%), threatened (28%), sporadic (20%), endangered (6.7%) and vulnerable (5.3 %). A total of 53 ailments (35human, 11 livestock and 7 both) were identified to be treated by medicinal plants. From the total identified medicinal plants, 54 of them were reported for the treatment of human ailments and the remaining others were for livestock and both. The dominant life forms of medicinal plants were shrubs 37(50%), followed by herbs 21(28%), trees 10(13%) and climbers7 (9%).The most preferably used medicinal plant parts were leaves 41 (55%) followed by roots16 (21 %). The dominant method of medicinal plant part remedy preparation was pounding and squeezing 26 (35 %) followed by pounding 15(20 %). The most common preferable route of administration of medicinal plant remedy was reported to be oral 39 (52%) followed by dermal 24 (32 %). Drinking was the most frequently used method of application26 (35%) followed by painting or creaming 21(28%). The main sources of knowledge on medicinal plants reported to be elder people and used oral based transfer of knowledge. Anthropogenic factors such as farm land expansion, charcoal production, fire wood, construction, animal grazing and medicine and natural factors were found to be the threats for medicinal plants. Promoting tree growing project and the sustainable utilization and management of medicinal plants were recommended. Further studies towards cultivation of medicinal plants of the area were needed.
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    Species Richness, Abundance and Habitat Preference of Rodents in Komto Protected Forest, Western Ethiopia
    (Addis Ababa University, 2010-06) Geleta Mosissa; Bekele Afework (Professor)
    A study on the species richness, abundance and habitat preference of rodents of Komto Protected Forest was carried out from July, 2009 to Feburary, 2010 encompassing both wet and dry seasons. The study was carried out using Sherman live and snap traps in maize farm, grassland, bushland and forest habitats. A total of 312 individual rodents (live traps) and 66 rodents (snap traps) were captured over 2352 and 1200 trap nights, respectively. The species composition and their relative abundance includes: S. albipes (48.4%), L. flavopunctatus (27.6%), L. striatus (10.3%), P. harringtoni (7.7%), R. rattus (5.1%) and M. mahomet (0.9%). In addition, a species of C. flavescens was also captured. Most of the rodent species prefer grassland and maize farm to bushland and forest. Bushland and forest habitats provided more number of individual rodents with few species. Males comprised 52.9% and females 47.1% of the total capture. Among the total rodents captured, adults, subadults and juveniles comprised 60.6 %, 28.8% and 10.6%, respectively. Active burrows were not recorded in all habitats during the wet season and in the grassland and forest habitats during both seasons. Population size was estimated by Minimum Number Alive method showed variation from 42 in Fubrary to 101 in September. High population density (309/ha) and biomass (8,048 g/ha) was recorded for S. albipes and lowest for M. mahomet (6/ha) and 29 g/ha, respectively. Seasonally, maximum biomass was obtained in September (5563 g/ha) and the lowest was in February (2,342 g/ha). Key words: Abundance, habitat preference, Komto Protected Forest, rodents, species richness