A Spatial Analysis of Effectiveness of Eradication of Invasive Species in Improving Grazing for Marginal Livestock Economies in Dryland of Matabeleland South Region, Zimbabwe: A Focus on Lantana camara and Opuntia fulgida
Oliver Dube, Joy-Noeleen Gugulethu Ndlovu, Ntandoyenkosi Ayanda Ncube
Department of Environmental Science and Health, Faculty of Applied Sciences, National University of Science and Technology, Bulawayo, Zimbabwe.
Abstract: Invasive alien plant species proliferation is accelerated by land disturbance such as recurrent droughts. The invasive species of concern in this study are Lantana camara and Opuntia fulgida with occurrence frequency of 43.8 % and 33.8% respectively in the dryland areas of Zimbabwe. This study was conducted in ward 14 and Ward 16, Gwanda and Bulilima Districts, respectively. The first step involved mapping the distribution and extent of eradicated areas in the two sites. A survey was carried out on randomly selected respondents where an assessment of knowledge, attitude, and economic gains due to eradication of invasive species, was determined. The study found that the actual reported loss of livestock in Bulilima resulting from Lantana camara poisoning was estimated at USD$7920/year. However, eradication recovered grazing potential of 37.6 hectares, an average carrying capacity of seven heard of cattle with a conservative total market value of $3500.00/yr. Nonetheless, this behavioural change was found to be strongly embedded in external monetary incentives with a frequency score of 88%, indicating an economic response to common property management. The study recommends an extensive use of multidisciplinary approach in the eradication of invasive species; a structured and pragmatic use of incentives.
Keywords: behaviour change, attitude, incentives, common property resources, opportunity cost
Pages: 429 – 450 | Full PDF Paper
Predicting Contour Slump Flow of Self-Compacting Concrete using Bentonite as Filler
Arabi N. S. Al Qadi1*, Madhar Haddad2
1. Department of Engineering, Ajloun National University, P.O. Box 43, 26810, Ajloun, Jordan.
2. Department of Architectural Engineering, United Arab Emirates University, P. O. Box 15551, Al Ain, UAE.
Abstract: This research presents the application of the Box-Benken design method to develop a model for predicting contour slump flow and its desirability in self-compacting concrete (SCC) with partial replacement of cement with bentonite. The slump flow has been measured for 15 mixtures prepared at the laboratories of Al Hussien Bin Talal University and Ajloun National University. The use of Bentonite as filler materials in self-compacting concrete can add many benefits that are directly related to the workability and consistency of various cementitious materials, besides the fact that it is possible to reduce the quantities of cement and optimize the percentage in the composite. The performance of the model can be judged by the Correlation Coefficient (R2), Mean Absolute Error (MAE) and Root Mean Square Error (MSE) which have been adopted as the comparative measures against the experimental results obtained from the mixtures, and found the best percentage of Mennonite in SCC.
Keywords: Box-Benken method; Bentonite; Self-compacting concrete; Contour slump flow
Pages: 451 – 460 | Full PDF Paper
The Effect of Balanites aegyptiaca (L.) Del. Fruit’s Shape and Location On Its Chemical Constituents
Somaya Omer M. Abdoun 1, Abdelazim Yassin Abdelgadir 2, Mubarak Elsiddig Elamin 3
1. Forests National Corporation, Khartoum, Sudan, Cell: +249 917879946.
2. Faculty of Forestry, University of Khartoum, Shambat street, Khartoum, Sudan, Cell: +249 912552592.
3. Industrial Research and Consultations Centre, Maowna street, Khartoum North, Sudan, Cell:+249 122118095.
The objective of the study was to investigate the effect of fruit shape and location on the chemical constituents (Sugars, saponins, protein, oil and moisture content) of Balanites aegyptiaca (L.) Del.fruit. Balanites aegyptiaca mature healthy fruits, were collected from Abu Jibeiha Province in western Sudan, and Dindir Province in eastern Sudan, in the period (2003-2005). The percentages of the fruit different parts were determined and chemical and statistical analysis (SAS) methods were carried out to obtain the percentages of sugar, saponin, protein, oil and moisture contents in the Balanites’ fruit as well as to detect the significant variation between shapes and locations.
The study found that, there were significant differences (P> 0.05), between the four fruit shapes (oblong, elongate, spherical and oval fruits) in the studied chemical constituents across and within sites and between locations.
The highest saponin content (4%) was obtained by oblong fruits while the highest invert sugar (40.9%) and oil content (44.9%) were obtained by oval fruits. Saponin average percentage obtained in Dindir location was double that obtained in Abu Jibeiha; the higher sugar percentage was obtained in Abu Jibeiha location. Protein content was found to be of higher content than that reported in the literature; it ranged between 49.6 (oval fruit) and 53.8% (oblong fruit). Moisture content was not significantly different between shapes and locations of a mean 9.3%. The study concluded with that, the amounts of sugar, saponin, oil and protein, in Balanites fruit; were found in considerable percentages calling to introduce Balanites different types to the food, pharmaceutical and medicinal industries.
Keywords: Balanites aegyptiaca, chemical constituents, saponin
Pages: 461 – 473 | Full PDF Paper