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Insights into landforms and soils for explaining plague hosts-vectors interaction in Western Usambara Mountains, Tanzania
No full textPhD. ThesisWestern Usambara Mountains in Lushoto District, Tanzania, are highly populated owing to favourable climatic conditions for production of both cash and food crops such as coffee, tea, maize, beans, potatoes and assorted fruits and vegetables. Some areas in the district are also potential as tourist destinations. However, clusters of villages in the district are reported to be hot-spots of plague recurrence that has caused deaths of thousands of people. Plague outbreaks in some villages of Lushoto District show a high frequency (on average, more than 1 year out of three) while other villages, very nearby (0.05) on burrow port orientation. The results showed that both soil depth and temperature encouraged burrow use in the high plague frequency landscape (p<0.05). Soil depth, dry soil consistence and subsoil relative humidity (RH (%) within 30 cm depth) significantly (p<0.05) could explain the burrow abundance in the medium plague frequency landscape. The use of burrows depended on the resistance of burrow to collapse, a characteristics which is dependent on the compaction of topsoil. However, dry subsoil consistence discouraged burrowing. Subsoil dry consistence had a significant (p<0.05) negative influence on burrow portal orientation in the medium plague frequency area, something attributed to compaction of the soils. It is concluded that soil physical and soil microclimate in the high plague frequency landscape encourage burrowing, a phenomenon correlating with the reported human plague contact risks. The information obtained from this study could be applied for surveillance, monitoring and control of rodent populations.Landscape-ecological Clarification of Bubonic Plague Distribution and Outbreaks in the Western Usambara Mountains, Tanzania (LEPUS) via VLIR own initiative projec
Insights into landforms and soils for explaining plague hosts-vectors interaction in Western Usambara Mountains, Tanzania
No full textPhD. ThesisWestern Usambara Mountains in Lushoto District, Tanzania, are highly populated owing to favourable climatic conditions for production of both cash and food crops such as coffee, tea, maize, beans, potatoes and assorted fruits and vegetables. Some areas in the district are also potential as tourist destinations. However, clusters of villages in the district are reported to be hot-spots of plague recurrence that has caused deaths of thousands of people. Plague outbreaks in some villages of Lushoto District show a high frequency (on average, more than 1 year out of three) while other villages, very nearby (0.05) on burrow port orientation. The results showed that both soil depth and temperature encouraged burrow use in the high plague frequency landscape (p<0.05). Soil depth, dry soil consistence and subsoil relative humidity (RH (%) within 30 cm depth) significantly (p<0.05) could explain the burrow abundance in the medium plague frequency landscape. The use of burrows depended on the resistance of burrow to collapse, a characteristics which is dependent on the compaction of topsoil. However, dry subsoil consistence discouraged burrowing. Subsoil dry consistence had a significant (p<0.05) negative influence on burrow portal orientation in the medium plague frequency area, something attributed to compaction of the soils. It is concluded that soil physical and soil microclimate in the high plague frequency landscape encourage burrowing, a phenomenon correlating with the reported human plague contact risks. The information obtained from this study could be applied for surveillance, monitoring and control of rodent populations.Landscape-ecological Clarification of Bubonic Plague Distribution and Outbreaks in the Western Usambara Mountains, Tanzania (LEPUS) via VLIR own initiative projec
Pedological investigation and characterization in Litembo village, Mbinga district, Tanzania
No full textDissertationA pedological investigation was carried out in Litembo village, Mbinga district
(Tanzania) to identify the various soil types and characterize them in terms of their
physical, chemical and mineralogical properties. The soils were classified according
to FAO-Unesco and USDA Soil Taxonomy systems. On the basis of soil and other
ecological parameters the potentials and constraints of the land resources were
assessed.
Standard soil survey methods and laboratory procedures were utilised to
generate both field and laboratory data.
Results indicate that Litembo village has four major landforms i.e. plateaux,
hills, piedmonts and valleys Most piedmont soils are deep to very deep having dark
brown to dark reddish brown sandy clay topsoils and dark red to red clayey subsoils.
The hills and plateaux have shallow sandy clay loam soils. All the studied soils are
well drained to excessively well drained except those of the valley bottoms which are
poorly drained.
Topsoil bulk densities range from 0.99 to 1.2 Mg m'3 whereas subsoil values
are slightly higher. Total porosity ranges from 56 to 72% in the topsoils and from 40
to 53% in the subsoils. Topsoils have lower penetrometer resistance (PR values 0.1
to 0.28 MPa) than subsoil (PR values 3.97 - 5.52 MPa). Available water capacity
(AWC) of most topsoils ranges from 15 to 25% by volume and the values decrease
slightly with depth. AWC per meter range from 125 to 177 mm which is medium to
high.
General soil fertility status is poor. Soil reaction is very strongly acid to strong
acid with pH values between 4.4 and 5.4 in topsoils and 4.4 and 6.0 in subsoils. Total
nitrogen ranges from very low to medium (< 0.03 - 0.3); phosphorus, bases, CEC
and base saturation are low. OC ranges from low to very high in topsoils and very
low in subsoils. The clay mineralogy is dominantly kaolinitic with accessory amounts
of gibbsite and goethite. The piedmont soils classified as Ferric Acrisols, Haplic
Acrisols and Humic Acrisols, plateau soils classified as Humic Acrisols; soils of the
as Dystnc Leptosols and Haplic Acrisols and valley bottom soils as Umbric Fluvisols.
From the results of this study it is concluded that Litembo soils developed
under intensive leaching environment, facilitated by a mountainous/hilly topography.
Fertility status is poor, and due to steep slopes and weak soil structure Litembo soils
are prone to erosion. The traditional farming system (ngoro) seems to control soil
erosion on steep slopes. It is recommended that steep slopes should be planted with
trees that will protect soil from erosion. Use of the traditional farming system (ngoro)
should be encouraged. Due to low soil fertility status, use of fertilizers both artificial
and organic manures is recommended Non-acidifying fertilizers should be preferable
because of the low soil pH values. The study area lacks climatic data. More research
in this line is recommended. Research on different land use alternatives which can
sustainably be applicable in the village should be carried out.Norwegian Agency for Development Cooperation (NORAD
Insights into landforms and soils for explaining plague hosts-vectors interaction in Western Usambara Mountains, Tanzania
No full textPhD. ThesisWestern Usambara Mountains in Lushoto District, Tanzania, are highly populated owing to favourable climatic conditions for production of both cash and food crops such as coffee, tea, maize, beans, potatoes and assorted fruits and vegetables. Some areas in the district are also potential as tourist destinations. However, clusters of villages in the district are reported to be hot-spots of plague recurrence that has caused deaths of thousands of people. Plague outbreaks in some villages of Lushoto District show a high frequency (on average, more than 1 year out of three) while other villages, very nearby (0.05) on burrow port orientation. The results showed that both soil depth and temperature encouraged burrow use in the high plague frequency landscape (p<0.05). Soil depth, dry soil consistence and subsoil relative humidity (RH (%) within 30 cm depth) significantly (p<0.05) could explain the burrow abundance in the medium plague frequency landscape. The use of burrows depended on the resistance of burrow to collapse, a characteristics which is dependent on the compaction of topsoil. However, dry subsoil consistence discouraged burrowing. Subsoil dry consistence had a significant (p<0.05) negative influence on burrow portal orientation in the medium plague frequency area, something attributed to compaction of the soils. It is concluded that soil physical and soil microclimate in the high plague frequency landscape encourage burrowing, a phenomenon correlating with the reported human plague contact risks. The information obtained from this study could be applied for surveillance, monitoring and control of rodent populations.Landscape-ecological Clarification of Bubonic Plague Distribution and Outbreaks in the Western Usambara Mountains, Tanzania (LEPUS) via VLIR own initiative projec
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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