Ethiopian Journals Online (EJOL)
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PEDOGENESIS AND SOIL·GEOMORPHIC RELATIONSHIPS ON THE PIEDMONT SLOPES OF WURGO VALLEY, SOUTHERN WELO, ETHIOPIA
No full textThe morphological, physical, chemical and mineralogical characteristics of six pedons were investigated to establish relationships that existbetween soils and geomorphic processes on the piedmont slopes of the Wurgo valley of southern Welo, Ethiopia. The results revealed that slope processes have played major role in the development of Eutric Cambisols with typical AlBw/Bb horizon sequences on the convergent footslopes. Luvic Phaeozems with A/Bt/Cr or A/Bt/Bb sequences on the non-convergent footslopes, and Eutric Vertisols with AIClCr or AI AC/Bb arrangements on the toeslopes. The Cambisols were weakly acid to neutral soils with loam to clay loam texture and cation exchange capacity (CEC) of 139 to 253 cmol(+)kg-! clay. The sand fraction in these soils is dominated by pyroxenes and volcanic clasts. The Phaeozems were marked by clay loam to clay texture, CEC of 113 to 203 cmol(+)kg-1 clay and sand fractions dominated by feldspars, volcanic clasts and laterite nodules. The Vertisols are heavy clay soils having CEC of 75 to 139 cmoI(+)kg-1 clay and sand fractions dominated by weathered volcanic clasts and laterite nodules. All of the characteristics used asindices of weathering suggest that the three soil units are at different stages of pedogenesis - the Cambisols being the youngest and the Vertisols the oldest soils. The major slope-related soil building process that resulted in the formation of Cambisols on the convergent footslopes was "cumulization" resulting from intermittent addition of alluvial and colluvial materials. Absence of "cumulization" on the other types of footslopes has allowed an uninterrupted operationof "lessivage" with subsequent development of argic B horizons within the subsoils of the Phaeozems. The active operation of "argilli pedoturbation" and "haploidization" and the subsequent development of Vertisols on the toeslopes was encouraged by the gentle to almost flat surfaces and the fine textured parent materials
INVERSION FOR SHEAR WAVE VELOCITY IN SEDIMENTS AND ESTIMATION OF NEAR-SURFACE ANELASTIC PARAMETERS
No full textStandard seismic refraction data recorded in North-East Italy, were used to define the shear wave velocities in sediments by means of the inversion of the Rayleigh wave dispersion relation. The group velocity for the fundamental mode and the phase velocity for the fundamental and first few higber modes were measured in the frequency range 'from 12 to 28 Hz. The inversion of these data gave a well defined S-wave velocity structure of the weathered zone to a depth of 38 meters. Using this information in the computation of complete synthetic seismograms for anelastic media, allowed a qualitative estimation, in the same depth range, of the distribution with depth of the quality factor, Q
UNIQUE DETERMINATION OF STRUCTURE AND VELOCITY BY 3-D TOMOGRAPHIC INVERSION OF REFLECTED AND REFRACTED WAVES
No full textAccurate determinations of interface depths and velocity fields are crucial for the oilindustries in their search for hydrocarbon reservoirs. However, the so called velocity-depth ambiguityhas always been a problem with the seismic reflection data that is normally used in petroleumexploration. In this paper the cause of this velocity-depth ambiguity is examined and a methodology isproposed that minimizes non-uniqueness in the inversion results. It is shown that simultaneousinversion of zero offset and offset reflection data as well as refraction data can reproduce accuratevelocity-depth model using only certain picked seismic events. A subsequent 2-D Prestack depthmigration based on the Kirchhoff method utilizing the velocity field obtained from the tomographicinversion extracts more information from the data and gives a clear picture of the subsurface. Thesuperiority of the simultaneous inversion of the reflected and refracted waves to that of reflected wavesalone is demonstrated using real dat
THE UNDIFFERENTIATED AFROMONTANE FOREST OF DENKORO IN THE CENTRAL HIGHLAND OF ETHIOPIA: A FLORISTIC AND STRUCTURAL ANALYSIS
No full textThe floristic composition and vegetation structure of Denkoro forest, South Wello Zoneof Amhara Region, N. Ethiopia, were described during November–December, 2002. A total of 95sample plots were analysed, and 174 species of vascular plants representing 66 families were recorded.Out of these, 41 species were new records reported for the first time from Wello. Eleven endemicspecies, which are included in the IUCN Red List categories, have been recorded. Based on the results ofvegetation classification, six clusters were recognized and designated as local plant community types: 1)Erica arborea - Hypericum revolutum, 2) Myrsine melanophloeos - Dombeya torrida, 3) Myrsine africana –Maesa lanceolata – Prunus africana, 4) Olinia rochetiana – Olea europaea, 5) Olinia rochetiana – Allophylusabyssinicus – Apodytes dimidiata, and 6) Maytenus gracilipes – Teclea nobilis. Structural analysis of the forestshowed the density of individuals > 10 cm DBH to be almost twice as that of individuals with DBH >20cm. A higher proportion of woody individuals (ca. 65%) fell in the low height classes (i.e., < 12 m).Analysis of population structure revealed five patterns, depicting the species dynamics in the forest.When compared with other forests in Ethiopia, Denkoro forest shows similarity to the dry evergreenmontane forests of the Central Plateau than those elsewher
EFFECT OF ORAL FRUCTOSE ADMINISTRATION ON ALCOHOL-INDUCED INCREASE IN PLASMA URATE
No full textOral fructose administration has been demonstrated to stimulate the oxidationof alcohol. However, its influence on alcohol-induced hyperuricemia is yet to bedocumented. This study therefore, reports the effect of fructose on alcohol- induced increasein plasma urate in adult albino rabbits. Twelve male adult albino rabbits, divided into A, Band C experimental groups were purchased from Yoha Farms, Warri, Delta State. Group A, thecontrol animals (n=4) were given normal saline, while Group B animals (n=4) orally received 1.5 g(40%) ethanol/kg body weight as single daily dose for a routine period of fifteen weeks.Group C rabbits (n=4) were treated in a similar manner. but 0.25 g fructose/kg body weightwas usually given after about 10 min of administerihg the ethanol dose. The results obtainedshow that ethanol administration significantly increased (P<0.05) serum urate by 57.8% atthe end of the 15-week tr~atment period but the serum urate levels for the ethanol· +fructose-treated animals only increased by 10.6%, an increase that was not statisticallysignificant at the 5% probability level. The stimulation of alcohol oxidative metabolism byfructose may not be accompanied by a threatening .increase in serum urate, the aetiologicrisk factor of gout, renal calculi and hypertension. Albeit, similar study designed for humansis needful in order to determine the suitability of aninlal model for predicting the possiblehuman effect(s)
VEGETATION UNDER DIFFERENT TREE SPECIES IN ACACIA WOODLAND IN THE RIFT VALLEY OF ETHIOPIA
Get PDFUnder-canopy vegetation was investigated in Senkele Sanctuary,Habemosa Cattle Ranch, Abjata-Shalla and Awash National Parks in the Rift Valley of Ethiopia to study the influence of some tree species on the environment under their canopies. Ten species of trees were selected for their relatively bigger canopy size and structure as subjects of the study. The relative abundance of the species in the herbaceous layer under the tree canopy were estimated and subjected to various multivariate numerical data analyses. Patchiness of the habitat on the tree canopy scale aggregated into five distinct groups with littleoverlap on the landscape scale suggesting that the vegetation beneath the tree canopy responded to environmental variables both under the tree canopies and in the landscape. The landscapes considered showed variation, among other things in altitude, temperature and precipitation. The vegetation under the tree canopies and the aggregations referred to as stratocoena, showed variations in cover,species richness and diversity. Economic implications were drawn for the variations in the herbaceous vegetation across tree canopy and landscape scale. It is argued that suitability of a tree for a particular purpose may depend on the environmental variables across the landscape scale as it does across tree canopy scale. Tree species suitable for agroforestry, developing grazing areas, creating patchy habitats and hence promoting biodiversity could be specific for each landscape considered
PREVALENCE OF INTESTINAL HELMINTHIC INFECTIONS AMONG HOUSEHOLD RATS IN ADDIS ABABA
Get PDFThis paper reports the prevalence of intestinal helminthicinfections among 101 Rattus rattus collected in Addis Ababa, from November. 1996 to December, 1997. Examination of faecal samples from each rat by the formol-ether concentration technique revealed that 441101 (43.6%) of the rats were positive for a single intestinal parasite: 311101 (30.7%) for Hymenolepis dimitulla, and' 13/101 (12.9%) for Hymenolepis nana. Double infection was recorded in 71101 (7%). Among the double infection, 3% were infected with H. diminuta and H. nana, and 4 % with H. diminuta and Syphacia obveleta. H. diminuta was the most frequent followed by H. nana. B. obveleta was found onlyin association with H. diminuta. The infection rates forcestodes in the present study were compared with the rates reported for cities in other countries. These findings suggest that household rats could be potential sources of human infections in the areas studie
REPRODUCTIVE BIOLOGY AND FEEDING HABITS OF THE CATFISH CLARlAS GARIEPINUS (BURCHELL) (PISCES: CLARIIDAE) IN LAKE AW ASSA, ETHIOPIA
Get PDFBreeding and feeding habits of the catfish Clarias gariepinus, inLake Awassa Ethiopia, were studied from samples collected between February 1987 and March 1988. Breeding started at the beginning of the early rains in February and continued until June, after which the proportion of breeding females declined gradually while the proportion of breeding males declined sharply. The sex ratio was not significantly different from unity, because 50.4 % females and 49.6% males were caught during the investigation. The smallest ripe female in the catch was 34.0 cm total length (TL) and the smallest ripe male caught was33.0 cm TL. The weight of ripe ovaries ranged from 11.2 to 962.0 g and the number of eggs ranged from 8,800 to 650,000 eggs. The number of wet weight of preserved eggs per gram ranged from 435 to 1176 with a mean of 669. C. gariepinus was found to be carnivorous in its feeding habit and fish was the most important food item. It contributed 81.7% of the food items of the juveniles and 86.8 % of the food of the adults by volume. A cichlid fish (Oreochromis niloticus) was the most utilized prey of C. gariepinus. O. niloticus accounted for 11.0% of the food eaten by juvenile fish (16.3-35.0 cm TL) and 77.5% of the food of adults by volume. Other food items found in the stomachs of C. gariepinusinclude insects, fish eggs, gastropods, pieces of macrophytes, detritus and zooplankton
ሶስተኛ ወገን መያዣው የኔ ነው በማለት በፍ/ቤት ክስ ሲያቀርብ መያዣው የመያዣ ሰጭው መሆኑን ከመያዣ ተቀባዩ ማስረዳት አለበት? የፌደራል ጠቅላይ ፍ/ቤት ሰበር ችሎት በሰ/መ/ቁ. 51001 በሰጠው ፍርድ ላይ የተሰጠ አስተያየት
No full textMetaphorical Conceptualization of Happiness in Anywaa
Get PDFIn the traditional approach, metaphor is understood as a rhetoric device used by talented people like poets and singers. This implies that metaphor is used only in language. However, after Lakoff and Johnson published Metaphors We Live By in 1980 based on Conceptual Metaphor Theory, this view was challenged with the argument that metaphor is a cognitive device with language being its physical manifestation. Thus, metaphor is used by ordinary people as part of their cognition. The present study aims at describing how the Anywaa conceptualize happiness. The theoretical framework used for the study was Conceptual Metaphor Theory. The data were obtained by using introspection, elicitation, recording and listening to daily utterances. The analyses and interpretations indicate that in Anywaa happiness is conceptualized based on source domains like TASTY FOOD, WHITE COLOUR, and SPATIAL ORIENTATION. Linguistic metaphors like jɪ̀ì mɛ́t dɔ́tʃ dītʃʌ́ŋɪ 'Your stomach is very delicious today’, j ̀ ɪ̀à wáárɔ̀'My stomach is white cotton', and tʃwíɲa jáá ŋááp máál bʌ̀ʌ̀t dʒáát̪ 'I have hanged my liver up in the tree' are some of the linguistic metaphors used to express happiness in Anywaa.The results indicate that in their conceptualization of happiness, the Anywaa select some sources over the others. For example, WHITE FLOUR is used as a source of happinness;however, RED FLOUR is not used although it is edible