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An Investigation into the Effects of Ant Control on Insect Populations (Hamcptera, Coccoidea) Of Citrus in the Eastern Cape Province, South Africa.
(University of Ghana, 1962-03) Brettell, J.H.; McC, E.; Ewer. D.W.; University of Ghana, College of Basic and Applied Sciences, School of Biological Sciences, Department of Animal Biology and Conservation Science (DABCS)
Deprofessionalization in Nursing?
(University of Ghana, 1969-07-29) Stinson, S. M.; Montag, M. L.; Warkov, S.; University of Ghana, College of Education, School of Education and Leadership, Department of Adult Education and Human Resource Studies
The thesis of this study is that the occupation of nursing is undergoing a process of deprofessionalization, not a process of professionalization as most of the major works in the nursing literature would seem to assume. The central purposes underlying this study were to reexamine and expand the concepts "profession" and "professionalization," develop the concept "deprofessionalization," and test the thesis in question. The approach used was that of a comparative social analysis, using current and historical data; the technique employed was that of a scholarly analysis of the literature. Because the concept "deprofessionalization" is a poorly developed one and because the thesis required that the concepts "profession" and “professionalization" be -developed, including an assessment of the impact of bureaucratization upon professionalization,four ..chapters _w￡tre devoted to these areas. Two major definitions of deprofessionalization were evolved: functional deprofessionalization was described as a process of "diseased professionalization," and dysfunctional deprofessionalization as a process of moving from a state of excessive professionalization to a state of functional professionalization. On the basis of the literature on professionalization, a documented case of deprofessionalization in law occurring in the nineteenth century, and upon examination of what would seem to constitute a case of deprofessionalization in diplomacy in the current century, a beginning typology was developed, the chief categories being: (1) direction (dysfunctional, functional), (2) duration (temporary, irreversible), (3! socio-political boundaries (international, continental, national, regional, state, local), (4) intraoccupational boundaries (intended to permit classification of deprofessionalization in "segments" of an occupation, e.g., criminal as opposed to corporate law, the bench as opposed to the bar), and (5) work-setting (underbureaucratized, bureaucratized, over-bureaucratized). Comparisons were made between professionalization in nursing c. 1920 and c. 1960, the former period being chosen because it both coincided with the heyday of solo practice in nursing, a characteristic frequently associated with the process of professionalization, and preceded the bulk of the immigration of nurses into bureaucratized work.-settings, a factor which the literature would suggest might contribute toward deprofessionalization. It was concluded that within the social context of the times, the occupation of nursing c. 1920 exemplified to a greater degree the characteristics of professionalization than is true of nursing today, some of the primary reasons being; (1) the relative integrity of the substantive knowledge-skill component, (2) the existence of a wellintegrated professional culture, (3) the substantial articulation of nursing roles with roles of related health personnel, (4) the relatively high degree of functional autonomy of the nursing practitioner, and (5) advancement in nursing was largely co-terminal with advanced technical expertise in nursing. Relevant categories of deprofessionalization were then applied to nursing c. 1960 and it was concluded that nursing is undergoing a process of dysfunctional deprofessionalization of the national and over-bureaucratization types. Whether it is of a temporary or irreversible nature, only history will reveal.
Availability and uptake of iron: Effect of ph changes during uptake of macronutrient ions
(University of Ghana, 1970-06) Adu, A.O.; Oertli, J.J.; Wallihan, E.F.; Page, A.L.; University of Ghana, College of Basic and Applied Sciences, School of Agriculture, Department of Soil Science
Long-term greenhouse experiments with corn (Zea mays) established that uptake of Fe from nutrient solutions may be significantly enhanced by increasing the supply of potassium. A mechanism was proposed to describe how uptake of macronutrient ions may in turn influence availability and uptake of Fe and other elements from their chelated and sparingly soluble compounds. It was hypothesized that since differential accumulation of cations is accompanied by a net release of H ions, and excess anion accumulation accompanied by a net release of OH ions, uptake of Fe, for example, will be enhanced by increasing supply of salts favoring differential accumulation of cations: The released H ions will acidify the root free space, root surfaces, and the immediate root environment; minerals on root surfaces will be dissolved and chelated molecules will be dissociated; both reactions will liberate ions most of which will diffuse.through a relatively high H ion environment to absorption sites in the roots. The hypothesis was tested in short-term absorption experiments in which corn seedlings were allowed to absorb Fe from FeEDDHA or Fehydroxide sols in the presence of increasing concentrations of salts of K, Na, Li, Mg, or Ca. Uptake of Fe was highest in the presence of salts from which excess cation accumulation is known to occur and in which the largest pH drop was observed. Increasing the concentration of K, as KC1 or K2 SO4 , from 0.0 to 5.0 or 10.0 mM K in unbuffered solutions or exchange resin suspensions at pH >_ 6.9 resulted in considerable pH decline and increased Fe uptake. The pH decline correlated with the enhancement of Fe uptake. However, acidification to below pH of about 4.7 tended to reduce further Fe uptake. No detectable pH changes occurred in CaC0 3 plus Fe-hydroxide suspensions containing increasing supply of K, yet Fe uptake was enhanced during accumulation of K. Since essentially all Fe supplied as Fe-hydroxide occurred as colloidal particles or precipitates, enhancement of Fe uptake was attributed to a three-ion-contact effect: Plants accumulating excess cations released H ions which decomposed or dissolved the Fe sols or precipitates on root surfaces, thus freeing Fe ions for absorption. Theoretical calculations indicated that increasing H-ion concentration in the immediate root environment will significantly enhance liberation of Fe+ ^ from the stable chelate FeEDDHA. Old hypotheses claiming that potassium ions in plants are directly involved in reactions favoring translocation and utilization of Fe were replaced with one relating K uptake to subsequent reactions in the substrate.
Development of the Bottom and Perihytic Invertebrate Fauna into the Volta Man-Made Lake during the First Years
(University of Ghana, 1970-07) Tomislav, P.
Development of the Bottom and Perihytic Invertebrate Fauna into the Volta Man-Made Lake during the First Years
The Interrelationship Between Scientific And Traditional Medical Systems. A Study Of Ghana.
(University of Ghana, 1972) Twumasi, P.A.
The study was devoted to the investigation of a common phenomenon in developing countries - i.e., the co-presence of scientific and traditional medical systems. The aim was to explicate the nature of the interrelationship between scientific and traditional medical systems, to discover the continuing functions of traditional medical practice, and to elucidate some of the determinants of the pattern of articulation between the medical systems and the larger society. The focus of the study was directed to Ghana, with implications for other developing countries. The study required a perspective which incorporated certain features of both a rational and a functionalist model. From the former the idea was developed that men plan consciously to take into account not only their successes but their recognized failures. From the latter, emphasis was placed upon the social system and its formally stated goals, considered as the main organizational ends. This perspective enabled us to focus upon one of the crucial problems in sociology: how a measure of integration, vis-a-vis the medical systems, is maintained in the face of inevitable changes from sources both external and internal to it. Methodologically, the study was limited to examination of published data; no primary field research has been carried out. The available data have been subjected to preliminary analysis in terms of the concepts and problems of contemporary social science. Four conclusions were reached: (1) that traditional medicine or its functional equivalent would never wholly disappear from the Ghanaian scene; (2) that the limited utility of scientific medicine in the area of psychosomatic disorders leaves a relatively permanent area of chronic ills within which traditional medicine may survive at least in the rural setting; (3) that an interaction occurs in the traditional setting between the two medical systems which tends to create a division of function between traditional and scientific medical practices; and (4) that a kind of pragmatism acts as a selective principle to help determine which method of treatment is chosen.
Comparative Ethology of the Large-Spotted Genet, Genetta Tigrina, and Related Viverrid Genera
(University of Ghana, 1972) Wemmer, C.; Eisenberg, J. F.; University of Ghana, College of Basic and Applied Sciences, School of Biological Sciences, Department of Animal Biology and Conservation Science (DABCS)
The niche of the small semi-arboreal, solitary, and nocturnal insectivore-carnivore is occupied by the genus Genetta over most of Africa and southwest Europe. The dozen or so species comprising the genus are structurally coherent, exploit nearly all natural and cultivated habitats, and in many areas are a numerically dominant small carnivore. This success may be considered exceptional, for Genetta like Didelphis and Tupaiia is believed to be a relatively unmodified derivative of an ancestral form (GREGORY and HELLMAU 1939) COLBERT 1955). However, the view that the viverrines are the most structurally conservative viverrids is founded on the premise that tribosphenic molars, attenuated body form, and relatively unrestricted rotatory ability of manus and pes constitute features of the ancestral morphotype (GREGORY and HELLMM 1939, COLBERT 1955, ROMER 19^5)• Since both fossil viverrines, such as the Oligocene and Miocene genera Paleoprionodon and Stenoplesictis and extant civets such as Prionodon, Viverricula, Poiana, and Genetta more or less share these features, the subfamily Viverrinae is considered to be the most central and basal viverrid group (WINGE 19^1, THENIUS and HOFER i960, GREGORY and HELLMAN 1939, COLBERT 1955, ROMER I9I+5).
Allelopathy as Expressed by Sugar Maple on Yellow Birch
(University of Ghana, 1972-07) Kweku, O.A.M.; Zahner, R.; Barnes, B.V.; University of Ghana, College of Basic and Applied Sciences, Forest and Horticultural Crop Research Centre
This study involves investigation of alleged inhibitory effects of leachate from sugar maple (Acer saccharum Marsh., donor plant) on yellow birch (Betula alleganiensis Britton., receiver plant). The term allelopathy, introduced by Molisch in 1937 refers to this phenomenon in which one plant produces a chemical which inhibits the growth of another plant. The present investigation follows from that of Tubbs (1970) into competition between maple and birch for light and moisture. His results showed that there is a striking difference in birch growth between those grown in pure culture and those grown with maple, the latter being much lower. This reduced growth could not be accounted for by mere physical competition, and through further investigations, he was able to attribute some of this reduction in growth to allelopathic effects of maple leachate. Tubbs postulated that the active principle causing the inhibition was exuded from maple roots, that it was thermostable, water soluble and ephemeral. The following questions which form the basis for the present investigations arise from Tubbs' results: 1. Is there a phenologic pattern to the inhibition of birch by maple? 2. Do maple organs, other than the roots, also exude inhibitor(s)? 3. How may the inhibition be expressed in birch? 4. What further can one learn about the chemical nature of the inhibitor(s)? These questions are being investigated with a view to providing answers that may help better understanding of the phenomenon of allelopathy between sugar maple and yellow birch. Literature Review No less than sixteen reviews of biochemical inhibitioi starting with one by Molisch (1937) to the recent review by Whittaker and Feeny (1971), have been published, not to mention also the many research papers which invariably contain partial reviews of the subject. It is intended here to reiterate various points in some of these review's and papers, particularly with regard to their relevance to the present investigation. The field of chemical inhibition traces back to 1828 when de Candolle drew the attention of scientists in his theory of crop rotation as a way of circumventing unfavorable effects of one species on another in soils (Schreiner and Reed 1907; Bonner 1950).
Cultural Ecology of Asante: 1702 - 1945
(University of Ghana, 1974-06) Boakye-Boateng, A.
The present can be considered as the product of the past" The truth of the statement is demonstrated in a study like this one which uses the genetic approach. Such an approach makes it possible for the present to be illuminated by the past: thus making it possible to explain many of the elements in the environment. This study on Asante reveals that the region had passed through two major socio-economic phases since the formation of the Asante Confederacy in about 1702. The date 1702, therefore, marks me beginning of the first phase which ends In 1901. During this phase the dominant force (theme) which controlled the cultural ecology was the Asante political power. The Asante Court controlled the main economic activities, namely, trade and gold mining; as well as me various crafts, such as goldsmithing, cire purdue metal casting, cloth making wood carving. The Court also controlled the population growth and distribution. Unfornmately, agriculture was not considered an important economic venture, therefore, it did not form part of the Court's delliberations. The Asante political power did not flourish forever. In 1902 this power oollapsed completely and Asante annexed to the British Crown. This saw the beginning of the second phase. This phase was characterized by the establishment of Pax Britanica. Within this peaceful atmosphere the cultivation of cocoa was encouraged. This was the era of commercial agriculture. It was this innovation which made all the difference in the cultural ecology of Asante. The processes In this phase ushered Asante into the contemporary by 1945. Indeed, by this date, it was clear that the basic characteristics of the contemporary cultural ecology were sketched. The various elements that make each phase distinctive have been treated with the view of showing both developments and changes that occurred.
Integrated Control of the Alfalfa Weevil, Hypera Postica (Gyllenhal) (Coleoptera: Curculionidae), in Ontario
(University of Ghana, 1976-01) Abu, J.F.; Ellis, C.R.; University of Ghana, College of Basic and Applied Sciences, School of Biological Sciences, Department of Animal Biology and Conservation Science (DABCS)
The distribution of the established parasitoids of the alfalfa weevil, Hypera postica (Gyllenhal) in western Ontario was determined during 1973 to 1975. Potasson luna (Girault), a parasitoid of eggs, was found in 13 out of 17 counties surveyed, but parasitism was only 0.7-17-0$. Tetrastichus incertus (Ratz.), a parasitoid of the larva, was recovered from only two sites and parasitism was less than k.0% at both places. Bathyplectes curculionis (Thomson), another parasitoid of the larva, was widespread and parasitism ranged from to 75-0$. Microctonus aethiopoides Loan, a parasitoid of the adult weevil, was recovered at only one site where parasitism was 33.3% in 19739 56.6% in 197^9 and 76.6% in 1975. The relationships between the alfalfa weevil and each of its two major parasitoids in Ontario, B. curculionis and M. aethiopoides, were investigated. Parasitism by B. curculionis was only 6.3-33.3% at the peak of the host population, but increased to 56.0-68.0% later in the season, when host population was low. The incidence of diapause as well as winter survival of B^ curculionis were highest among parasitoid cocoons obtained towards the end of the season. The populations of the first generation adults of M. aethiopoides was synchronized well with those of the overwintered adult weevils, resulting in parasitism of 76.6-82.0%. The second generation of the adult parasitoids and the summer adult weevils overlapped for about two weeks and parasitism was 1+1.6-60.0$. Some adults of M. aethiopoides were present in the field when hosts were unavailable and this may have significance in the establishment of the parasitoid at new release sites. Parasitism by M. aethiopoides did not significantly affect the overwintering mortality of the alfalfa weevil. The toxicity of five insecticides, carbofuran, carbaryl, malathion, phosmet, and methoxychlor was determined by topical application in the laboratory on adult B. curculionis, adult M. aethiopoides, third-instar larvae of H . postica, third-instar larvae of H. postica parasitized by B. curculionis, adult H. postica and adult H . postica parasitized by aethiopoides. The effect of these five insecticides in an integrated control program was assessed, using selectivity ratios calculated as the of the parasitoid divided by the of weevil larva or adult. Each of the insecticides was more toxic to the two parasitoids than to the host larvae but, comparatively, carbofuran and carbaryl were 2 to 3 times safer to the parasitoids than malathion, phosmet, or methoxychlor. Carbofuran, the only insecticide which was selective in favour of both parasitoids over the adult weevils, had selectivity ratios 2 to i times those of malathion, phosmet, carbaryl, and methoxychlor. Parasitized larvae and adults of H^_ postica were more susceptible to the insecticides than were their non-parasitized counterparts and most of the parasitoid larvae died within the susceptible hosts. The weevil larvae were much more tolerant to all the insecticides than were the adults. Based on the selectivity ratings, carbofuran and carbaryl are preferable to malathion, phosmet, or methoxychlor in the integrated control of the alfalfa weevil. Because adults are more susceptible than larvae and since there is a period in the spring when adult weevils are active in the field while adult parasitoids are not, the feasibility of chemical control against the adult weevil should be investigated further. Such a recommendation could have application in alfalfa seed production where early cutting is not an alternative and control is usually required each year
The Role of Adult Education in the Adoption of Innovations by Cocoa Growers in Ghana
(University of Ghana, 1976-03) Opare, K.D; University of Ghana, College of Education, School of Information and Communication Studies, Department of Information Studies
This study was designed to analyse the adoption of recommended cocoa practices among cocoa growers in Ghana and to relate it to the correctness of their knowledge of principles underlying the recommende practices, the growers' sources of cocoa husbandry information selected personal and economic characteristics of the growers; and to examine the relationships discovered and to draw recommendations which will assist the Ghana Government in programmes to increase cocoa production. In order to study these relationships, a personal interview, using a structured interview schedule, was employed to collect the data from a sample of 1,191 cocoa growers in Ghana. Statistically significant association? were found between the adoption of recommended cocoa practices and 1) the correctness of growers' knowledge of principles underlying a recommended cocoa practice; 2) adult education sources of information; and 3) individual grower's output of cocoa. The study indicated that although the possession of correct knowledge of principles was crucial to the adoption of the innovations, the mere possession was not always sufficient motivation to effect adoption. An equally important factor was adult education sources of information. In addition, there was no indication that the adoption of recommended practices was more closely linked with correctness of knowledge than with adult education sources of information. Among the personal and economic characteristics studied, number of wives, number of children, advisory role and number of years engaged in cocoa growing were positively associated with adoption of recommended practices. Male growers were more apt to adopt innovations than female growers. Age was not related to adoption. Literacy was positively associated with adoption of recommended practices. The study shows that possession of correct knowledge of principles is crucial to adoption of recommended cocoa practices. Thus, access to formal instructional activities could contribute to the improved performance of cocoa growers in Ghana. An obvious mechanism for improvement is adult education for the growers.
Effect of Maturity on Dry Matter Accumulation and Quality of Forage from Natural Grassland and Three Introduced Grasses in the Accra Plains, Ghana
(University of Ghana, 1977-12) Fianu, F.K.; Winch, J.E.; University of Ghana,College of Basic and Applied Sciences School of Agriculture Department of Animal Science.
EFFECT OF MATURITY ON DRY MATTER ACCUMULATION AND QUALITY OF FORAGE FROM NATURAL GRASSLAND AND THREE INTRODUCED GRASSES IN THE ACCRA PLAINS, GHANA Francis Kwasivie Fianu, Supervisor: University of Guelph, 1977 Dr. J.E. Winch Two studies were conducted in Legon, Ghana, in 1974 and- 1975 to characterize the dry matter accumulation and quality of a natural grassland sward (dominated by Sporobolus and Heteropogon) and of introduced giant star grass (Cynodon plectostachyus (k . Schum) Pilger), buffel grass (Cenchrus ciliaris L. cv. biloela) and pangola grass (Digitaria decumbens Stent.). The natural grassland study was a split plot experiment with pretreatment slashing, grazing and burning in the main plots and.ten harvest dates during the major rainy season in the subplots. Each of the ten subplots was subdivided into three parts and harvested sequentially at the end of the rainy season, mid-dry season and at the end of the dry season. Pretreatments did not affect the botanical composition, dry matter accumulation during the growing season or regrowth during the ensuing dry period. Sporobolus p.yramidalis Beauv. grew faster than Heteropogon contortus (L.) Beauv. at the early stages, dominated the sward and flowered at 3-6 weeks. Heteropogon initially grew slowly and flowered from week 6. By week 7 Heteropogon became the dominant species of the sward. Cenchrus sp., Bothriochloa sp. and Setaria sp. flowered within 4-fc weeks but gamba grass (Andropogon gayanus Kunth.) did notflower during the study. Dry matter accumulation in the natural grassland sward and its dominant species continued after flowering until the end of the rainy season. Leaf production, and the In Vitro digestibility as well as nitrogen content of Sporobolus and Heteropogon were not affected by pretreatment. While Sporobolus maintained a high percentage of leaf throughout the growing season, leaf proportions dropped in Heteropogon at the mature stages. Leaves were more digestible and contained more nitrogen than stems in both species. Heteropogon tended to be more digestible than Sporobolus. The two species were similar in leaf and whole plant nitrogen, but Sporobolus stems contained more nitrogen than those of Heteropogon. In the study on introduced grasses, giant star and buffel were harvested at ten dates during the minor rainy season of 1974 (September 16 - December 3l)j during the major rainy season of 1975≫ pangola grass was included in the experiment. Pangola was sensitive to moisture stress during early growth and failed to grow during the minor rainy season of 1974* Buffel, on the other hand, was drought tolerant and grew even under light showers. Buffel flowered from week 3 in both seasons while giant star flowered only during the minor rainy season at week 6 , and pangola flowered in week 6 during the major rainy season. Growth continued in all three grasses after flowering. In buffel, senescent leaves were retained on the plant whereas in the stoloniferous grasses, they were stripped off by rainfall. During the minor rainy season, giant star and buffel produced similar dry matter yields. In the major rainy season, however, buffel was superior in yield to the prostrate grasses which showed np consistent differences. Leaf dry matter yield increased until week 8-9* Buffel and giant star produced more leaf dry matter than pangola grass. Leaf proportions in the plant declined steeply with maturity in buffel grass but slowly in the prostrate grasses. During the minor rainy season, whole plant In Vitro digestibility and nitrogen were similar in giant star and buffel during the minor rainy season, but buffel had the highest whole plant digestibility followed by pangola and giant star was the least digestible. The leaves were more digestible than stems, this difference being most striking in mature buffel grass. Leaf nitrogen levels were higher than stem nitrogen levels in all the grasses but species differences in nitrogen content were not consistent. The nitrogen content of whole plants would probably be adequate for the maintenance requirements of a steer until week 7 during the minor rainy season and week 11 in the major rainy season. In Vitro digestibility was highly correlated with nitrogen content of leaves, stems and whole plants of all species except giant star stem. It would appear that buffel grass should be harvested at 5 weeks and giant star at 7 weeks during the minor rainy season. In the major rainy season buffel would be harvested at 9 weeks and giant star and pangola at 8 weeks for optimum combination of nutrient yield during the rainy season and regrowth during the ensuing dry period. The natural grassland species and the introduced grasses were similar in digestibility at the early stages but the erect grasses -natural and introduced - declined more rapidly than the prostrate introduced ones. For high animal performance both the natural and the introduced species would have to be supplemented with concentrates.
Life History Of Chrysichthys Catfish In Volta Lake,Ghana.
(University of Ghana, 1979) Vanderpuye, CJ.
This study, undertaken during 1974 to 1977 in Volta Lake, investigated the identification, abundance and distribution, reproductive biology and weight-length relationships of four Chrysichthys species (C . a u ratus, C. walkeri, C. velifer and C. furcatus). The species were separated on basis of position of the dorsal fin, color of the barbels and the body and shape of the caudal fin and its lobes. Gill rakers also proved of some value. The Volta Lake, on the Volta River in Ghana, is the largest manmade lake (area: 8,700 km^). It was dammed in 1964 and reached the m a x i mum controllable level in 1968. The northern narrower arms are of riverine character and the southern section, lacustrine. Water temperatures range between 26.5 to 30.5°C throughout the year. Except in periods of overturn (usually between December to March and June to August), dissolved oxygen is considerably reduced below 10 m. Ampem station, established on one of the main arms of the lake, was sampled monthly (except 9 out of 29 months) with gill nets of graded mesh size, a beach seine, traps (hoop nets) and rotenone. Other stations, in the various sections of the lake, were also sampled occasionally. ln 196 5 Chrysichthys were relatively abundant near the dam at Akosombo. Sampling in 1970 showed a decline and a more even lakewide Life history of Chrysichthys catfish in Volta Lake, Ghana University of Ghana http://ugspace.ug.edu.gh distribution with indications of higher abundance in the southern (more lacustrine) areas. Thereafter, abundance fluctuated seasonally with more fish being caught in the rainy season. Chrysichthys were seldom found deeper than 10 m, probably because of low dissolved oxygen concentrations. Chrysichthys also were seldom found in higher currents. Length frequency data did not indicate different year classes or spawning periods but were characterized by single modes which remained fairly constant over a 6 -month period. Spawning C. walkeri and C. auratus were taken in traps fabricated from bamboo stems. Spawning was in a sheltered bay at depths of 1.0-1.5 m over a firm substrate and egg masses were placed in darkened interior of the bamboo traps. The smallest (standard lengths) spawning males, and females were respectively 76 m m and 82 mm (C. auratus) and 82 m m and 72 m m (C. walkeri). Males were larger than their mates in 42 of the 43 pairs collected in the bamboo traps. The number of eggs per female increased linearly with weight for C. walkeri and with weight and length for C. velifer and linearly with the log lengths of C. walkeri and C. auratus. The slopes for functional regressions of log weight on log length did not differ significantly from 3.0 for C. walkeri and C. velifer but was less than 3.0 for C. auratus and C. furcatus.
The Influence of the Brukung Cult in the Social Organization of Shiare
(University of Ghana, 1979-06) Pollock, R.
Dynamics of Forest and Thickest Vegetation on the Accra plains, Ghana
(University of Ghana, 1979-06) Lieberian, D.D.; Hall, J.B.; University of Ghana, College of Basic and Applied Sciences ,School of Biological Sciences , Department of Botany
Aspects of seasonal dynamics, population dynamics, and successional dynamics were investigated in three kinds of woody vegetation which occur on the Accra Plains: dry tropical forest, large thickets, and isolated clumps of thicket. Flowering, fruiting, foliage behaviour, and girth changes show a strong seasonal pattern in the study area; moisture deficits limit phenological activity within the community, although patterns vary among species. Synchrony was high within species in reproductive phenology and girth changes, and was high within the community in foliage behaviour. Synchronous flushing was shown to be a significant mechanism of herbivore escape in species lacking alternative defences such as hairy leaves or chemical deterrents. The success rate of fruit set during the study period was low; this probably resulted from both pollination failure and moisture stress. Girth increments for the year were negative, due to the unusually low rainfall. Patterns of seed dispersal and vegetative regeneration tend to maintain the floristic identity of thicket and forest respectively; little mixing between habitats occurs in the seed rain, and differential mortality of seedlings further constrains the adult species composition in the two habitats. Root suckering is particularly important in thicket clumps, due to the mosaic nature of the habitat. Regeneration is adequate in both thicket and forest to maintain the vegetation in a steady-state, although during the study period, seedling mortality exceeded recruitment. Species of closed canopy dry forest showed good stocking in all size classes; some gap-exploiting species were deficient in the small size classes or showed a highly irregular size class distribution. In most species, survivorship rates were constant from one size class to the next through the first stage of the tree's growth (up to 201 of its maximum size), improving in the later stage; in two understorey species, survivorship rates were constant throughout the lifespan of the tree. Successional patterns within the forest are dominated by patchy disturbances (caused by tree falls); gaps are filled by any of a number of rather rare, long-lived emergent species, and old gaps show higher species diversity than is found in other areas. In the absence of disturbance, the composition converges on a low-diversity forest dominated by Diospyros abyssinica, Drypetes parvifolia, and Drypetes floribunda. Most species in the forest show clumped dispersion, resulting from patterns of seed dispersal and vegetative regeneration. Forest of the Accra Plains appears to be stable under present climatic conditions. Reduced rainfall probably has the effect of reducing the cover of woody vegetation, and the damaging effect of fire and wind may be augmented under particularly dry conditions. Changes in vegetation resulting from drought, fire, and wind are neither rapid nor pronounced. Cutting of wood, however, quickly brings about apparently irreversible changes in the species composition, physiognomy, and stature of the vegetation: a dense, low thicket replaces the forest, and this thicket is, itself, stable under the influence of further cutting. Thicket clumps, which differ floristically from both forest and large thickets, exist as isolated relics of more continuous thicket vegetation where the moisture level is insufficient to support larger patches of woody vegetation.
Solute Dispersion in Soil
(University of Ghana, 1979-07) Laryea, K. B.; Elrick, D. E.; University of Ghana, College of Basic and Applied Sciences, School of Physical and Mathematical Sciences, Department of Earth Science.
An experimental study of solute transport during one-dimensional sorption of a solution of KC1 into a uniformly packed horizontal soil column of Akuse clay, (a tropical clay loam from Ghana which is dominantly montmorillonitic) and Brookston clay of the Huron Catena (dominantly illitic) is reported in this thesis. A hydrodynamic equation based on the existing theories of irreversible thermodynamics is developed to incorporate the effect of anion exclusion in the usual hydrodynamic equation for one-dimensional flow of solute in soil. This equation is used to calculate the. longitudinal dispersion coefficient D^ in horizontal infiltration experiments where anion exclusion effects were observed. Also, the analysis of hydrodynamic dispersion during one-dimensional horizontal flow developed by Smiles eit al. (1978) is extended to include gravitational effects present during one-dimensional vertical infiltration by using the power series form of solution developed by Elrick _et a^L. (1979). Simulation methods using computer programs written in system/360 Continuous System Modeling Program (CSMP) are used to solve the equations used in this study. The longitudinal dispersion coefficient is in all the analyses presented in this study, assumed to be independent of the Darcy flux and a function of the water content only. In all experiments, both the soil solution content, the chloride concentration and the potassium concentration preserved similarity in terms of distance divided by square root of time. This confirmed the assumption that the longitudinal dispersion coefficient is effectively independent of the Darcy flux for the conditions of the experiments reported in this study. These results were found to be consistent with the studies of Saffman (1959) , Pfannkuch (1963) and Scotter and Raats (1970). The observed incomplete piston-like displacement of the antecedent water content suggests the presence of stagnant or 'immobile' water fractions in the soil columns considered. The derived longitudinal dispersion coefficient for Cl agreed fairly well with the derived longitudinal dispersion coefficient for K . This is an indication that under the experimental conditions imposed, the equilibrium adsorption isotherm used to describe the adsorption term in the hydrodynamic equation for solutes which interact with soil particles, is adequate. Simulation of water content, chloride concentration and concen- + - 1/2 tration of K as a function of X(=xt ) using derived data D(X), Dg (X) for Cl and Dg (X) for K+ showed very good agreement with experimental data. The simulated c(X) for Cl also showed excellent agreement with calculation of c(X) using a program for the analytical solution. Water content profile and chloride concentration profile obtained for vertical infiltration experiments indicated good agreement with theoretical water content and Cl concentration profile simulated with CSMP. The theoretical chloride concentration profiles showed a progressively dispersed 'front' with long infiltration time periods whereas the theoretical water content profiles for various time periods showed a sharp and abrupt wetting front
Akyem Abuakwa C.1874 - 1943: A Study of the Impact of Missionary Activities and Colonial Rule on a Traditional State
(University of Ghana, 1980-04) Addo-Fening, R.
This thesis is a study of the nature and extent of the pressures -social, economic and political - that the Basel Missionaries and British colonial Administrators brought to bear on Akyem Abuakwa society during the period 1874-1943. The study also examines the state's responses to these pressures and the extent to which they were conditioned by her pre-european historical experience, her ethos, the strengths and weaknesses of her institutional arrangements, the quality of her political leadership and her resources. The general conclusions that emerge from this study are that missionary activities and colonial policies brought a great deal of material progress to Akyem Abuakwa society: the quality of life was improved by the spread of western-style education, by the adoption of new skills, by improved medical care and by infrastructural developments; changes in the customary penal system made the administration of justice more humane; while the evolution of a modem-style bureaucracy at the courts of the chiefs and the adoption of certain administrative routines enabled the complicated and diverse functions of modem government to be effectively discharged. Those positive results were, however, off-set by negative and harmful results: the spiritual foundations of Akyem Abuakwa were seriously undermined by widespread and wilful violation of time-honoured customary taboos by missionary converts in the name of religious freedom as well as by the introduction of a dichotomy between 'church’ and ‘state’, between religion and politics; the cohesion and solidarity of Abuakwa society suffered great damage by the creation of salems whose Christian inhabitants held aloof from the life of the wider community; existing social conflicts were sharpened while new, more serious and harmful ones were introduced by the concept of territorial jurisdiction as embodied in the N.J.O., by the distortion of the character and role of chieftaincy, and by the destruction of the religious conformity of the state; the wakening of extended family ties, growing emphasis on individualism and the failure of Christianity to deal adequately with the trauma. of rapid social and. economic change created problems of security which expressed themselves in alcoholism and neurosis; above all the exploitation of Abuakwa’s immense resources -human and natural - for the greater benefit of her alien rulers resulted in the under-development of the state.
Immunological Investigation of Malaria in Ghana
(University of Ghana, 1980-05) Quakyi, I.A.; Voller, A; Kane, G.J.; University of Ghana, College of Basic and Applied Sciences, School of Biological Sciences, Department of Botany
A comprehensive immunological survey of malaria in rural and urban populations in Ghana is reported. Sera from Ghanaians resident in Ghana and Ghanaian students resident in the United Kingdom and Germany, pregnant women, blood donors and from patients with acute malaria, nephrotic syndrome, tropical splenomegaly, Burkitt's lymphoma, schistosomiasis, onchocerciasis and tuberculosis were included. Control sera were obtained from healthy adult Caucasians, Caucasians with connective tissue and parasitic diseases other than malaria, non-immune Caucasians with primary malaria infections and Nigerians. Serum from monkeys (Macaca mulatta) infected with P.knowlesi were also tested. Infecting parasites were identified by examination of blood slides. Malarial antibodies were detected by enzyme immunoassay (ELISA) and immunofluorescence (IFA). Antibodies to M.tuberculosis, V.cholerae, T.pallidum, E .histolytica, T.gondii, T.gambiense, T.rhodesiense, S.mansoni and T.canis were determined by a 'rapid' IFA test. Onchocercal antibodies were determined by ELISA using 0.gutturosa antigen. Antibodies to Epstein Barr Viral Capsid Antigen (VCA) and hepatitis B surface antigen (HBsAg) were measured by IFA and passive haemagglutination inhibition respectively. Serum levels of IgG, IgA, IgM, IgE, albumin, complement C3, C3 converted products, immune complexes and autoimmune antibodies were measured. All data were analysed by computer. The value of ELISA in the diagnosis and epidemiology of malarial infection was demonstrated in this study and the results showed good correlation with those obtained by immunofluorescence. Both tests were employed in the studies of malaria in rural and urban populations. The analysis of parasitological and serological indices obtained for the 2 populations confirmed the endemicity of malaria in Ghana: Plasmodium falciparum was the predominant species) prevalence rates were higher in the rural than the urban population) antibody levels in both populations showed an agerelated increase. The overall sero-epidemiological findings thus conformed to the classical concept of the acquisition of malarial immunity and suggested that a stable state of malaria prevails in Ghana. This survey revealed a high incidence of autoantibodies, raised levels of soluble immune complexes and evidence of in vivo complement activation in malaria. It has been suggested that in malaria, antigen-antibody complexes stimulate immune effector mechanisms. Products of these might interfere with the development of protective immunity and result in the initiation of immune complex diseases and its perpetuation. The findings reported would support this hypothesis.
Methionine Metabolism in Filarial Worms
(University of Ghana, 1980-09) Acquaah, R.A.; Oduro, K.K.; Jaffe, J.J.; Gyang, F.N.; University of Ghana, College of Basic and Applied Sciences, School of Biological Sciences, Department of Biochemistry, Cell and Molecular Biology
Adult filariae apparently lack the vitamin BI2-dependent and -independent methyltransferases for the de novo synthesis of methionine and seem to meet their requirement of this amino acid from an exogenous source and the activity of S-adenosylmethionine(AdoMet):homocysteine S-methyltransferase The properties of filarial AdoMet:homocysteine methyl transferase were similar to the analogous microbial enzyme. However, adult filariae possess the enzymatic capability to metabolize methionine to cyst(e)ine. When incubated in the presence of L-{CH3-14C} methionine to induce them to synthesise AdoMet, adult Dirofilaria immitis incorporated the radiolabel into phospholipid and protein fractions. The significance of filarial methionine metabolism especially with regard to its suitability as a potential target for antifilarial chemotherapy is discussed.
Influence Of Plant Resistence And Nematicides On Growth And Yield Of Tomato (Lycopersicon Esculentum) And On Population Dynamics Of Root-Knot Nematodes (Meloidogyne Incognita And Meloidogyne Hapla ) With An Asociated Study Rooted-Knot Nematode Resistance In Lettuce (Lactuca Species)
(Cornell University, 1982-08) Bonsi, C.K.; University of Ghana, College of Basic and Applied Sciences, School of Agriculture, Department of Crop Science
The influence of resistant tomato cultivars, chemical applications and both in combination on the population dynamics of root-knot nematode species (Meloidogyne incognita and Meloidogyne hap!a) and on growth and yield of subsequent susceptible tomato crops was studied. Both growth chamber and field experiments were conducted. High initial inoculum densities (P.) of root knot nematode species reduced growth but had slight or no effect on growth of resistant cultivars. Nematode reproduction was positively correlated with the initial inoculum density. M. incognita was more virulent than M. hapla on the susceptible (Rutgers) tomato. VFN-8 was found to be partially resistant to M. hapla. Continuous cropping of a susceptible cultivar in infested soil greatly increased the nematode population and decreased the growth of susceptible plants. Resistant cultivars or applications of Vorlex alone permitted one (at highest P.'s) and two to three (at lowest P^s) susceptible crops to be grown before the nematode population reached a plant damaging level. Applications of Vorlex after a crop of resistant cultivar resulted in sufficient reductions of the nematode populations that at least three successive crops of the susceptible cultivar could be grown before the population reached a plant damaging level. A lower dosage of chemical was needed when used in combination with a resistant cultivar to control root knot nematodes. In field experiments, Vorlex significantly increased marketable yields of tomatoes. Further increases in marketable yields of Rutgers tomato were obtained when Vorlex was applied to infested soil that had been previously planted to a resistant cultivar. In another study, only the resistant tomato seedlings when transplanted after 2 wk from highly infested to noninfested soil, grew as well as those transplanted from noninfested to noninfested soil. In the third study, none of either the Lactuca species or the lettuce breeding lines tested were resistant to M. incognita and M. javanica. JL. saliqna and L.. dregeana were resistant to a greenhouse population of M. hapla but were susceptible to a field population of M. hapla.
The Systematics of Indo-Pacific Saur1va and Trachinocephalus (Pisces: Synodontidae) and the Biology of Four Local Species
(University of Ghana, 1984-03) Adjei, E. L.; University of Ghana, College of Basic and Applied Sciences, School of Biological Sciences, Department of Animal Biology and Conservation Science (DABCS)
Lizardfish species of the genera Saurida Cuvier and Valenciennes and Traohinoeephalus Gill 1862 in the Indo- Pacific are morphologically cryptic and widely distributed. Their habitats range from shallow water to deeper waters, sand/muddy bottoms or reefs. Many morphological features of lizardfish are variable and often of limited value in establishing taxonomic relationships. Synonymies and especially misidentifications are prevalent. An exploratory electrophoretic analysis confirmed intra-specific variation but also revealed specific differences which reflected species affinities. Accordingly the diagnosis of Indo-Pacific Saurida is revised and eleven species - S. argentea, S. australis, S. elongata, S. filamentosa, S. flamma, S. gracilis, S. isarankurai, S. longimanus, S. nebulosa, S. tumbil and S. undosquamis - are described. 5. australis is removed from the synonymy of S. undosquamis and interrelationships between members of the genus are described. S. wanieso and S. micropectoralis both described by Shindo and Yamada (1972) are synonymized under S. filamentosa and S. argentea respectively. S. wanieso is considered as a geographical race of S. filamentosa whereas S. micropectoralis is, by priority, a junior synonym of S. argentea. The biology of lizardfish were studied from collections taken within and without Moreton Bay between August 1979 and December 1981. The analysis of stomach items and morphological adaptations revealed that the food and feeding strategies of lizardfish consist of adaptability to a wide range of food items, food sizes and environmental conditions instead of specialization to few food items. The most important component of stomach items (by frequency of occurrence) were fish in over 85% of stomachs analysed (i.e. those with food). The other two major components were Crustacea and Cephalopods in about 5-16% and about 7% respectively. Stomach content analysis indicated that lizardfish fed during both day and night. Mouth and body structures are well suited to their hunting techniques and carnivorous mode of feeding. Lizardfish reproduction within and without Moreton Bay is described with emphasis on the development of the gonads. Four types of eggs based on size and yolk content are described. Eight and six stages of identifiable gonads based on a) types and quantities of ova present and b) texture and macroscopic appearance are described for the ovaries and testes respectively. The species exhibit size polymorphism - the females predominate in sizes greater than male S.L^q whereas the males predominate in sizes about the male S.L.^q and below. The reproductive strategy involves an extended spawning season, early maturation, high fecundity coupled with serial spawning. The ages of S. tumbil, S. undosquamis and T. myops on the one hand and S. filamentosa on the other were determined by the scale and vertebrae methods respectively and were supplemented by the length frequency method. The observed maximum ages in the species were 5, 4, 12 and 3 for S. undosquamis, S. tumbil, S filamentosa and T. myops respectively. Lizardfish growth is asymptotic and alloraetric and was described in terms of Von Bertalanffy and other growth parameters. The overall growth strategy apparently involves a number of features - very rapid linear growth, early maturation, annual and allometric growth. The four lizardfish species were parasitized by cestodes, hemiurid trematodes, nematodes, isopods and acanthocephalans. Negative binomial distribution (truncated and non-truncated) analyses in comparison with actual frequency distribution of the most common parasite in Moreton Bay, Callitetrarhynohus gracilis (Rudolphi) 1819, suggested that ’heavily’ infected fish were missing from the samples.

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