Articles, Conference and Workshop Papers Collection

Permanent URI for this collectionhttp://10.10.97.169:4000/handle/123456789/68

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Balancing wood and non-wood products in Miombo Woodlands
(2007) Makonda, F. B. S.; Gillah, P. R.
In most of the sub-Saharan countries including Tanzania, Mozambique, Malawi, Zimbabwe and Zambia, more than 80% of rural people are poor and traditionally rely on existing non-wood goods and services provided by miombo. These woodlands are among the most threatened of the tropical ecosystems. There is a need of investigating the importance of miombo ecosystem, their threats and the governments concerned to ensure sustainable and equitable use of these dwindling resources. This paper gives an overview of the roles played by miombo in the provision of both wood and non-wood products and how the utilization can be balanced for sustainability. It is evident that there has been limited research on miombo productivity and the impact of management on non-timber product supplies. This needs immediate attention in order to address the demand-supply situation. Also sustainable use of trees and shrubs is an integral part of balancing variable products and uses in miombo woodlands. Conservation of miombo while raising the living standard can be enhanced through controlled harvesting, improved domestication and utilization and commercialization of trees and their products.
Potentials of lesser known and lesser utilized indigenous agroforestry timbers in Kilosa District, Morogoro Tanzania
(International Journal of Education and Research, 2015-11-12) Makonda, F. B. S.; Augustino, S.; Gillah, P. R.; Ishengoma, R. C.; Kitojo, D. H.; Ruffo, C.; Eriksen, S.; Msanga, H. P.
The paper presents baseline results of gathered important information for inference in establishing optimal production and utilization of Lesser-known (LK) and Lesser-utilized (LU) indigenous agroforestry timber species (IAGTS) in improving incomes of rural communities in Kilosa District. The main key questions were: what are the characteristics of the sites for establishing LK and LU IAGTS; who are the main actors in establishing LK and LU IAGTS; what are LK and LU IAGTS and other species for establishment in the study area and what are the strengths, weaknesses, opportunities and threats for establishing LK and LU IAGTS in the study area. Data collection was participatory, involving key stakeholders, participants’ observations and literature surveys. A total of eight villages were identified as potential sites for nursery establishment with seven main actors’ mostly local communities engaged in tree planting activities under associations. Five priority LK and LU IAGTS were identified and selected for nursery establishment. These were: Lonchocarpus capassa (Mfumbili), Sclerocarya birrea (Mng’ongo), Vitex doniana (Mfudu), Pseudolachnostylis maprouneifolia (Msolo) and Combretum zeyheri (Mlama mweupe). The strengths and opportunities favouring the establishment of LK and LU IAGTS nurseries were identified, with a few weaknesses and threats which needed to be worked upon.
Properties of celtiz zenkeri engel: a lesser-known timber species from Kilindi District, Tanzania
(Tanzania Journal of Forestry and Nature Conservation, 2009) Gillah, P. R.; Makonda, F. B. S; Kitojo, D. H.; Ishengoma, R. C.; Khalid, S.
This study was conducted to provide some of the basic physical and strength properties of wood of Celtis zenkeri Engel. which is among the lesser-known and lesser-utilized timber species from Tanzania. Celtis zenkeri belonging to the family Ulmaceae is currently being harvested for wood fuel and building poles thus being under-valued and placed in class V timbers since the basic properties of its wood are not yet known. The objective of this study was therefore, to determine and assess some of the basic physical and mechanical properties of C. zenkeri specifically colour, texture, basic density, Static bending (Modulus of Flasticity, Modulus of Rupture, Work to maximum Load and Total work), Compression parallel to grain, Shear and Cleavage stress. Relationships between basic density and the mechanical properties were also assessed. Data for this study were collected from three mature and defect free sample trees objectively selected from Kilindi district in Tanga region. Each sample tree produced three logs; from bottom, middle and upper part of the bole. Test specimens were extracted from the samples and by using standard methods, the physical and mechanical properties were determined. The following are the wood strength properties obtained for C. zenkeri. Basic density (655 kg m-3) and Total Work (21,916 N mm-2), Modules of rapture (198 N mm-2), Work to maximum load (0.360 N mm-3) and Total Work (0.598 N mm-2). Others are; Cleavage strength (24.56 N mm-width), compression strength (97.1 N mm-2) and Shear strength (28.7 N mm-1) Celtis zenkeri wood was found to have desirable values to be used for hand tools, joinery, building, plywood, artificial limbs and flooring furniture.
Properties of nesogordonia holtzh subsp hotzii (Moss) capuron: a lesser known timber species from Kilindi District, Tanzania
(Tanzania Journal of Forestry and Nature Conservation, 2009) Gillah, P. R.; Makonda, F. B. S.; Kitojo, D. H.; Ishengoma, R. C.
Nesogordonia holtzii subsp holtzii (Moss) Capuron is a lesser-known timber species belonging to the family Sterculiaceae. The species is distributed in the eastern tropical Africa in association with other tree species as Newtonia buchananii, Albizia versicolor, Allanblackia stuhlmanii, Antiaris toxicaria and Sterculia appendiculata. Currently it is harvested for fuelwood and building poles thus being under-valued, Due to its wood technical properties not known to users it is placed in royalty fee class V timbers. The objective of this study was therefore to determine and assess some basic physical and mechanical properties of N. holtzii. Compare the determined strength properties of N. holtzii with those from well known tree species. Use different combinations of the properties of N. holtzii obtained to assign suitable end uses and promote it for its utilization. Three mature sample trees free from visible defects were selected randomly. Each tree was sampled to produced three logs. Test specimens were extracted from the sample logs using the method by Larvers (1969). Physical and strength properties determination was carried out according to the procedure described in ISO 3131(1975) ISO3133 (1975) BS 373(1957, 1976) Larvers (1969) and Panshin and de Zeeuw (1970). The results showed that N. holtzii was found to have yellow timber that turns reddish brown on seasoning and the wood is fine textured. The average basic density is 593 kg m-3 Modulus of Elasticity 7,606 N/mm-3, Modulus of Rupture 81 N/mm-2, Work to Maximum Load 0.098 N mm-3, Total Work 0.196 N mm-3, Compression Stress 48.83 N mm- 2, Shear Stress 11.40 N mm-2 and Cleavage Strength 24.98 N mm-1. These properties are within the acceptable range for the building and furniture industry. As many traditional timbers become scarcer, the timber of Nesogordonia holtzii should be promoted and is recommended as a substitute for Afzelia quanzensis, Pterocarpus angolensis and Newtonia buchananii. The resemblance in colour allows these timber species to be sold in one group.
Some physical and mechanical properties of Uapaca Kirkiana, a lesser-known timber species from Tanzania
(Tanzania Journal of Forestry and Nature Conservation, 2007) Gillah, P. R.; Makonda, F. B.; Ishengoma, R. C.; Kadala, B.; Kitojo, D. H.
This study was carried out to determine some physical and mechanical properties of Uapaca kirkiana a lesser known timber species growing in public land near Iyondo Catchment Forest Reserve, Kilombero District, Morogoro, Tanzania. A total of 3 trees were used in the study. Preparation of test samples and laboratory procedure to determine some physical and mechanical properties followed standard methods. Analysis of variance was used to determine the variation between and within trees and regression analysis was used to determine relationship between wood basic density and mechanical properties. The results showed that Uapaca kirkiana has whitish sapwood and dark brown heartwood, with a mean basic density of 518.14 kg/m3. The properties of Uapaca kirkiana were as follows: modulus of elasticity (7185.69 N/mm2), modulus of rupture (59.7 N/mm2), work to maximum load (0.06 mmN/mm3), total work to failure (0.07 mmN/mm3), shear strength parallel to the grain (11.86 N/mm2), compression strength parallel to the grain (34.4 N/mm2) and cleavage strength (20.21 N/mm width). On axial direction, the modulus of elasticity, total work to failure, compression strength parallel to grain and cleavage strength were directly proportional to its basic density while modulus of rupture, work to maximum load and shear strength parallel to the grain were inversely proportional implying that Uapaca kirkiana is suitable for activities, which require high modulus of elasticity, total work to failure, compression strength parallel to the grain and cleavage strength. On radial direction modulus of elasticity, modulus of rupture, work to maximum load, compression parallel to the grain and cleavage strength were directly proportional to basic density while shear parallel to the grain was inversely proportional to basic density. Compared to Khaya anthotheca, the timber species found in the same location and market; it was found that the timber of Uapaca kirkiana had modulus of rupture and compression parallel to the grain far lower than those of Khaya anthotheca, while the work to maximum load, total work to failure, shear strength parallel to grain and modulus of elasticity were almost the same. Due to the similarity in some of their physical and mechanical properties, the wood of Uapaca kirkiana may berecommended to substitute Khaya anthotheca in wood works that require medium density wood like in decoration where colour is considered an important aspect for appearance and in cabinet, panel and furniture making though it is not adequate in high-class strength joinery.
Some physical and strength properties of lesser known aphloia theiformis timber from Lushoto Tanga, Tanzania
(Tanzania Journal of Forestry and Nature Conservation, 2008-07-14) Gillah, P. R.; Makonda, F. B. S.; Hussein, I.; Augustino, S.; Kitojo, D. H.
Some physical and strength properties of lesser known Aphloia theiformis timber grown in and around Magamba Forest Reserve, Lushoto district, Tanga region were determined. A total of three sample trees were randomly selected and felled for this study. Test samples for moisture content, basic density and Strength properties determination were prepared and tested according to Lavers (1969), BS 373 (1957), ISO 3130 (1975), ISO 3131 (1975), ISO 3133 (1975) and ISO 3349 (1975). It was observed that Aphloia theiformis timber has a sapwood and heartwood colour ranging from creamcoloured to whitish pink resembling that of Grevillea robusta. The average basic density was 519 kg/m3 with a standard deviation of 4.2 which can be classified as medium-density timber. The basic density showed a slight decrease from butt end to top end. Regarding strength properties, Aphloia theiformis timber had a mean modulus of rupture of about 55.8 N/mm2 and modulus of elasticity of about 3854 N/mm2. The work to the maximum load was about 0.06mmN mm-3, while total work averaged 0.08mmN mm-3. The compression and shear parallel to the grain were 37.4 and 12.6N mm-2 respectively. Furthermore, all strength properties of Aphloia theiformis were positively correlated with basic density. The properties of this timber were also comparable to properties of Grevilea robusta and are always rated the same by timber dealers. While Aphloia theiformis had higher tearing strength than Grevillea robusta, the modulus of rupture and compression parallel to the grain values were comparable. Aphloia theiformis can therefore substitute Grevilea robusta in many areas of its application.
Timber properties of lesser known polyscias fulva (hiern) harms and allophylus abyssinicus hochst. radlk. from Iringa Tanzania
(Tanzania Journal of Forestry and Nature Conservation, 2008) Makonda, F. B. S.; Gillah, P. R.; Augustino, S.; Valentine, S.
Two lesser-known and lesser utilized timber species namely Polyscias fulva and Allophyllus abyssinicus from Iringa, Tanzania were studied to determine basic density and some strength properties. Three trees for each species were randomly selected, felled, test sampled prepared and properties tested according to standard methods. Data analysis was conducted employing Microsoft excel computer software where descriptive statistics were computed. Analysis of variation was done to establish relationships existing between density and strength properties. Variation in basic density between trees and t-test was carried out to compare wood properties of the two species. In addition, regression analysis was used to establish the existing relationship. Tests of strength properties on clear specimens showed that on average, the overall strength properties for Polyscias fulva and Allophyllus abyssinicus were comparable respectively to Pinus caribaea and Terminalia superba, the commercially utilized timber species in Tanzania. Further, with exception of compression parallel to grain, the two species were significantly different. There was statistically significant difference within species in basic density and strength properties with exception of modulus of rupture and cleavage strength for Polyscias fulva and work to maximum load, compression parallel to the grain and cleavage for Allophylus abyssinicus. Furthermore, there were direct relationships between basic density and strength properties for the two timber species. While Pinus patula can substitute Polyscias fulva, Terminalia superba can substitute Allophyllus abyssinicus in most of its applications. The two timber species can be used for light construction work, sporting goods and furniture making. Further work on the studied species is required on other strength as well as chemical properties and natural durability.
Vitex doniana sweet: A potential lesser-known and lesser utilized agro-forestry timber species in Kilosa District, Morogoro Tanzania
(2016-01) Makonda, F. B. S.; Kitojo, D, H.; Augustino, S.; Ruffo, C.; Ishengoma, R. C.; Gillah, P. R.; Eriksen, E.; Msanga, H. P.
Tanzania is classified as among the 15 poorest nations in the world, with an estimated per capita income of less than US$ 190. Over 80 % of the country’s population of about 46 million lives in rural areas. Living in such a poor country, the people have few feasible alternatives to exploiting the forest resources resulting in high deforestation rate estimated at 2 % annually. Nevertheless, many timber species are still not known to users, resulting into over-exploitation of few well-known timber species. The timber stakeholders need alternatives and the national economies need better ways to derive value from the remaining forests in order to maintain their many useful but under-valued functions. One option is to optimize the production and utilization of lesser-known and lesser-utilized indigenous timber species which are potential for agro-forestry. One of such species is Vitex doniana Sweet which belongs to the family Lamiaceae. It is a deciduous tree with medium-growth rate and is widespread in tropical Africa. V. doniana is being threatened by habitat loss. This paper attempts to analyze some potentials of V. doniana as an agroforestry tree. The studied properties were: i) Physical – Tree dimension, form and quality, wood colour, texture, workability and basic density ii) Strength - Static bending, compression, shear and cleavage and iii) Anatomical - growth rings, vessels arrangement, density and size, gum deposits, parenchyma and ray tissue. The average physical properties are as follows: The sapwood is white while the heartwood is pale greyish-brown and basic density is 650 kg m-3. The strength properties are: Modulus of elasticity (11,100 N mm-2), Modulus of rapture (98.14 N mm-2), Work to maximum load before failure (0.131 mm N mm-3) and Total Work (0.239 mm N mm-3). The impact bending strength was 1.02 m, Hardness (4,580 N), Compression parallel to the grain (52.5 N mm-2), Shear parallel to the grain (15.6 N mm-2) and Cleavage (9.0 N mm-1). This species depicts well-marked growth rings and therefore ring-porous, meaning a course textured timber. The average strength properties are closely comparable to those of Tectona grandis (Teak). Also, Vitex doniana has other multiple benefits: bears edible fruits, suitable as ornamental tree and windbreak, shade and its leaves are useful as vegetable and as well as for soil improvement.

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Browsing Articles, Conference and Workshop Papers Collection by Author "Gillah, P. R."