Association of Striga Infestation to Basic Chemical and Physical Properties of the Soil in Tigray Region, Northern Ethiopia

A survey was conducted in 2014 to determine the association of striga with major chemical and physical properties of the soil. Similarly, strong association was observed between striga infestation and soil pH (r(22)=-0.213, P<0.05), available phosphorous (r(22) =-0.408, P<0.05), percent organic matter (r(22) =-0.917, P<0.05), total nitrogen (r(22)=-0.097, P>0.05) and soil texture . The influence of soil organic matter on level of striga infestation was observed superior (84%) to other soil chemical and physical properties. In conclusion, the highest level of striga infestation was recorded at kebeles which had got low soil organic matter and available phosphorous and sandy textured soils. Therefore management practices channeled towards improving these limitations have been suggested for controlling of Striga hermonthica in the region. Keywords: striga infestation, sorghum population, soil properties, correlation, Tigray regio

Designing and implementing a GIS-based cadastral database for land administration in the city of Asmara, Eritrea.

Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.The knowledge and application of land information and GIS in Eritrea are very limited and as a result there is a shortage of sufficient, reliable, up-to-date and modem land information for decision-making. This study aimed to develop and design a GIS-based cadastral database for land administration in the city of Asmara, Eritrea. The two components of the cadastral data, the spatial and non-spatial were collected and processed in a GIS environment. GIS-based cadastral data was created to store the data. A recently acquired IKONOS image and existing Auto CAD data were the main sources of data for the study. Geo-rectification, conversion, ,building of topology, spatial adjustment, and digitizing were used' for creating the parcels and roads of Asmara city. A key of relation was created to link both the spatial and non-spatial components of the cadastre. The study used illustrated practical examples to show how GIS-based cadastral data could support land administration as practiced by the different divisions of the Municipal Office of Asmara city. The importance and usage of the cadastral database for urban planners and property valuators were detailed. Spatial and network analysis were used to develop bands for creating a banded property appraisal system for assessing the service catchment area~ of hospitals and the only fire station. Further, a location allocation model was <,I:lso developed to recommend suitable sites for new fire stations in the city of Asmara. It is recommended that the Municipal Office of Asmara adopts the designed GIS-based database. It is also recommended there the major cities in Eritrea follow similar methodology to design and implement cadastre database for their administration

A hybrid partial least squares and random forest approach to modelling forest structural attributes using multispectral remote sensing data

Up to date forest inventory data has become increasingly essential for sustainable planning and management of a commercial forest plantation. Forest inventory data may be collected in the form of traditional field based approaches or using remote sensing techniques. The aim of this study was to examine the utility of the partial least squares regression (PLSR), random forest (RF) and a PLSR-RF hybrid machine learning approach for the prediction of four forest structural attributes: (basal area, volume, dominant tree height and mean tree height) within a commercial Eucalyptus forest plantation using a combination of spectral and textural information of high spatial resolution (0.15m) remote sensing data. The best model for this study was produced for mature E. dunnii species for dominant tree height using the PLSR-RF hybrid model (R2 = 0.82 and RMSE = 2.07m). The results of this study highlight the robustness and potential of the PLSR-RF hybrid model for the prediction of forest structural attributes using high resolution imagery within a commercial Eucalyptus forest plantation

Prevalence and factors associated with unmet need for family planning among the currently married reproductive age women in Shire-Enda- Slassie, Northern West of Tigray, Ethiopia 2015: a community based cross-sectional study

Introduction: Unmet family planning is one of the common causes for low contraceptive prevalence rate in developing countries including Ethiopia. Thus, this study designed to assess the prevalence and associated factors of unmet need in Shire Endaslassie town, Northern west of Tigray, Ethiopia. Methods: A community based cross sectional study design was employed. Multistage sampling technique was employed and data were collected using a semi-structured questionnaire by interviewer administered technique. Questionnaires were reviewed and checked for completeness, accuracy and consistency. Reviewed data were entered to Epi info 7 and analyzed by SPSS version 20 statistical software. Variables with P-value of less than 0.2 in bivariate analyses were entered for multivariate analysis and AOR at 95% CI with p-value of less than 0.05 were considered as significant variables. Results: The overall unmet need for family planning in the study area was 109(21.4%). 74(14.5%) for spacing and 35(6.9%) for limiting. Age group of 35-39 and &gt;=40 (AOR= 2.7,95%CI:1.1,6.5), (AOR=2.65, 95%CI:1.10, 6.40) respectively, decided numbers of desired children more than five (AOR=O.48, 95%CI: 0.28, 0.80), discussions of client with heath care providers (AOR=6.32, 95%CI: 2.56, 15.58), previous use of modern family planning (AOR=2.29, 95%CI, 1.20, 4.34) were significantly associated with unmet need for family planning. Conclusion: Unmet need for family planning in the study area was high, so continuous discussion on modern family planning with community health workers and encouraging of women to decide desired numbers of children of less than five in general are better to be strengthened.Pan African Medical Journal 2016; 2

Monitoring urban growth around Rustenburg, South Africa, using SPOT 5

Understanding urban spatial growth is critical for sustainable urban infrastructure and service planning. Urban growth information is an important input into predicting future land cover and land use change and sustainable growth management. Rapid urbanization has resulted in expanded urban land use and has led to population explosions in urban areas and undesirable environmental impacts in South Africa. This research is aimed at studying urban spatial growth of Rustenburg city in South Africa from 2007 to 2012 using temporal imagery acquired by Satellite Pour l’Observation de la Terra (SPOT) 5 satellite. Multi-temporal images acquired in 2007, 2009 and 2012 were used to assess urban spatial growth of Rustenburg. Post-classification change detection method was used to quantify urban growth. For the purpose of this study, only two classes, urban and non-urban land use classes, were mapped and assessed. The urban spatial growth between 2007 and 2009 was 16.8% while 8.7% urban growth was observed between 2009 and 2012. The total spatial urban growth between 2007 and 2012 was 25.5%. This information can be used by the municipal authorities and decision makers as input during urban and environmental planning

Socio-economic status as predictors of malaria transmission in KwaZulu-Natal, South Africa. A retrospective study

Background: Understanding the socioeconomic status that influences malaria transmission in KwaZulu-Natal, South Africa is vital in creating policies and strategies to combat malaria transmission, improve socioeconomic conditions and strengthen the malaria elimination campaign. Objectives: To determine the relationship between socioeconomic status and malaria incidence in KwaZulu-Natal, South Africa. Methods: Socioeconomic information (gender, age, no formal education, no electricity, no toilet facilities, unemployment) and malaria data for 2011 were obtained from Statistics South Africa and the malaria control program of KwaZulu-Natal, South Africa respectively. The analysis was conducted employing the Bayesian multiple regression model. Results: The obtained posterior samples show that all the variables employed in this study were significant and positive predictors of malaria disease at 95% credible interval. The low socioeconomic status that exhibited the strongest association with malaria risk was lack of toilet facilities (odd ratio =12.39; 95% credible interval = 0.61, 24.36). This was followed by no formal education (odd ratio =11.11; 95% credible interval = 0.51, 24.10) and lack of electricity supply (odd ratio =8.94; 95% credible interval = 0.31, 23.21) respectively. Conclusions: Low socioeconomic status potentially sustains malaria transmission and burden. As an implication, poverty alleviation and malaria intervention resources should be incorporated side by side into the socioeconomic framework to attain zero malaria transmission. Keywords: Malaria; socialeconomic status; Bayesian modelling; KwaZulu-Natal; South Africa

The estimation of Eucalyptus plantation forest structural attributes using medium and high spatial resolution satellite imagery.

Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2008.Sustaining the socioeconomic and ecological benefits of South African plantation forests is challenging. A more systematic and rapid forest inventory system is required by forest managers. This study investigates the utility of medium (ASTER 15 m) and high (IKONOS 1-4 m) spatial resolution satellite imageries in an effort to improve the remote capture of structural attributes of even-aged Eucalyptus plantations grown in the warm temperate climatic zone of southern KwaZulu-Natal, South Africa. The conversion of image data to surface reflectance is a pre-requisite for the establishment of relationships between satellite remote sensing data and ground collected forest structural data. In this study image-based atmospheric correction methods applied on ASTER and IKONOS imagery were evaluated for the purpose of retrieving surface reflectance of plantation forests. Multiple linear regression and canonical correlation analyses were used to develop models for the prediction of plantation forest structural attributes from ASTER data. Artificial neural networks and multiple linear regression were also used to develop models for the assessment of plantation forests structural attributes from IKONOS data. The plantation forest structural attributes considered in this study included: stems per hectare, diameter at breast height, mean tree height, basal area, and volume. In addition, location based stems per hectare were determined using high spatial resolution panchromatic IKONOS data where variable and fixed window sizes of local maxima were employed. The image-based dark object subtraction (DOS) model was better suited for atmospheric correction of ASTER and IKONOS imagery of the study area. The medium spatial resolution data were not amenable to estimating even-aged Eucalyptus forest structural attributes. It is still encouraging that up to 64 % of variation could be explained by using medium spatial resolution data. The results from high spatial resolution data showed a promising result where the ARMSE% values obtained for stems per hectare, diameter at breast height, tree height, basal area and volume are 7.9, 5.1, 5.8, 8.7 and 8.7, respectively. Results such as these bode well for the application of high spatial resolution imagery to forest structural assessment. The results from the location based estimation of stems per hectare illustrated that a variable window size approach developed in this study is highly accurate. The overall accuracy using a variable window size was 85% (RMSE of 189 trees per hectare). The overall findings presented in this study are encouraging and show that high spatial resolution imagery was successful in predicting even-aged Eucalyptus forest structural attributes in the warm temperate climates of South Africa, with acceptable accuracy

Structural determination of a series of synthetic peptide analogues to the 310-helical (Pro138-Gly144) segment of aquaporin-4 by X- ray crystallography

In order to understand the single crystal X-ray structures of a series of synthetic peptides mimicking the Pro138-Gly144 segment of human AQP4 [1] , we have crystallized and determined the X-ray structures of some of these peptides. The crystal structure of the peptides Boc-Pro-Pro-OH (1), Boc-Aib-Aib-OMe in two polymorphs (2 and 3), Boc-Val-Val-OMe (4), and the tripeptide Boc-allylSer-Aib-Val-OMe (5), were elucidated. Peptide 1, C15H24N2O5, was designed and synthesized to the corresponding N-terminal Pro138-Pro139 segment of the 310-helix loop C (Pro138-Pro139-Ser140-Val141-Val142-Gly143-Gly144) of the AQP4. The compound crystallized in the orthorhombic space group P212121 with one molecule in the asymmetric unit. tBoc-Pro bond and Pro-Pro along the peptide bond show cis- and trans-conformations (cis-trans), approximately with ω = -8.2° and ω = -174.35°, respectively. Proline residues in 1 adopt incipient Poly-L-proline type I (PPI) and type II (PPII) backbone conformations. Orthorhombic and monoclinic form of the same compound has been determined so far by different authors. Finally, the backbone conformation of 1 is compared with these two forms (orthorhombic and monoclinic form) as well as with the Pro138-Pro139 segment of AQP4 at 1.8 Å and 3.2 Å resolutions. The peptide C14H26N2O5 was obtained in two polymorphic forms (2 and 3), both exist in the monoclinic space group P21/c and P21/n, respectively with one molecule in the asymmetric unit. The Aib residues in Boc-Aib-Aib-OMe adopt (φ, ψ)-values which are characteristics of helical conformations. The dihedral angles of the peptide backbone show that the Aib residues lie in left- or right-handed 310- /α-helical regions in the Ramachandran plot. The torsion angles indicate values for folded conformations. 13 Peptide 4, C16H30N2O5, was designed and synthesized to the corresponding Val141-Val142 segment of the AQP4 loop C. It was crystallized in the orthorhombic space group P212121 with three molecules in the asymmetric unit. Each molecule in the asymmetric unit adopts a β- strand/polyproline II backbone conformation. The main chain functional groups are hydrogen bonded into tapes carrying the characteristics of parallel β-sheets. Each tape has a left-handed twist and thus forms a helix, with six peptide molecules needed to complete a full 360° rotation. A comparison of hydrogen bond lengths and twisting mode is made with other related structures of protected dipeptides. Additionally, a comparison of the backbone conformation is made with that of the Val141-Val142 segment of the water channel aquaporin-4. Peptide 5, C21H37N3O7, crystallize in the monoclinic space group C2 with a single molecule in the asymmetric unit. A single crystal X-ray diffraction studies of 5 reveals that it adopts a bend (or turn-like structure) without any intramolecular hydrogen bonding. Most of the dihedral angles of the tripeptide 5 fall within the helical region of the Ramachandran plot

Soil carbon estimation from eucalyptus grandis using canopy spectra

Mapping soil fertility parameters, such as soil carbon (C), is fundamentally important for forest management and research related to forest growth and climate change. This study seeks to establish the link between  Eucalyptus grandis canopy spectra and soil carbon using raw and continuum-removed spectra. Canopy-level  spectra were collected using a hand-held 350-2500nm spectroradiometer and soil samples obtained at depths from 0-1.2m and analysed for carbon content. Partial least squares (PLS) selection was used to selected  optimal bands for soil carbon assessment and further bootstrapped to select 35 Variable Importance in  Projection (VIP) parameters, based on correlation (r) and standard error (SE). Results indicated that  continuum-removed spectra and soil C yielded stronger significant correlations, when compared to soil C and  raw spectra. The predictive models developed for future soil C estimation showed that continuum-removed  spectra exhibited improved adjusted R2 values in both instances, i.e., when using all significant bands and the  most significant 35 VIP bands. The results indicate a distinct potential for forest managers to monitor the  status of soil C in commercial forestry compartments using canopy-level spectra and determine how much  fertilizer is required to optimize tree growth.Keywords: Soil carbon, Canopy spectr

Remote sensing object-oriented approaches coupled with ecological informatics to map invasive plant species

nvasive alien plants are considered one of the major threats to biodiversity conservation worldwide. Hence, understanding their distribution and abundance is important in order to assess the impact on native ecosystems. It is particularly important to be able to track the spread of invasive species across landscapes; a task best achieved using remotely sensed imagery. The availability of high resolution data, combined with efficient classification methods, can potentially improve early detection of invasive alien species thereby enhancing their management. This study aims to classify woody species with a focus on Melia azedarach (Meliaceae) trees in a moderately invaded coastal belt valley on the east coast of South Africa using WorldView-2 (WV-2) satellite imagery, and to compare the commonly used pixel-based classification with object-oriented approaches. The results show that object-oriented approaches are more suitable for classifying woody species, as well as other land cover classes when using high-resolution WV-2 imagery. The overall accuracy was 90% by object- oriented classification, while the pixel-based classification gave an overall accuracy of 78%. For Melia, a producer accuracy of 92% and user accuracy of 91% was obtained by object-oriented classification and a producer accuracy of 85% and user accuracy of 83% was obtained by pixel-based classification. Hence the combined use of new generation sensor imagery and the employment of object-oriented image classification techniques provided more accurate information on Melia invasion in the study area. This is an encouraging result given the high degree of intermingling of Melia with other plants at the study site. In particular, the vegetation maps produced from this study would aid in gathering accurate knowledge about the distribution and spreading status of Melia, a major invasivespecies over large areas of South Africa and elsewhere in the world