Infestation Density of Eucalyptus Gall Wasp, Leptocybe invasa Fisher and La Salle (Hymenoptera: Eulophidae) on Five Commercially Grown Eucalyptus Species in Tanzania

24pThis study explores infestation density of Leptocybe invasa on five commercially grown Eucalyptus species in Coastal, Plateaux, and Southern Highlands agroecological zones of Tanzania. Infestation density between agroecological zones, Eucalyptus species, age classes and tree crown parts, relationship between stand altitudes and the magnitude of infestation, damage index, species age, and abundance of L. invasa on different Eucalyptus species were examined. There were significant differences in infestation between zones and Eucalyptus species. Eucalyptus tereticornis was more affected, followed by E. camaldulensis, andE. saligna was the least while E. grandis and E. citriodora were not affected. No significant differences in damage between different crown parts were observed.Treeswithageof1–3yrweredamagedmorethanthoseof age 4–6 yr. Pest infestation increased with an increase of L. invasa abundance but decreased with an increase of altitudes. Control efforts needs to focus on controlling the spread of the pest, using silvicultural methods and planting resistant Eucalyptus species

Infestation Density of Eucalyptus Gall Wasp, Leptocybe invasa Fisher and La Salle (Hymenoptera: Eulophidae) on Five Commercially Grown Eucalyptus Species in Tanzania

24pThis study explores infestation density of Leptocybe invasa on five commercially grown Eucalyptus species in Coastal, Plateaux, and Southern Highlands agroecological zones of Tanzania. Infestation density between agroecological zones, Eucalyptus species, age classes and tree crown parts, relationship between stand altitudes and the magnitude of infestation, damage index, species age, and abundance of L. invasa on different Eucalyptus species were examined. There were significant differences in infestation between zones and Eucalyptus species. Eucalyptus tereticornis was more affected, followed by E. camaldulensis, andE. saligna was the least while E. grandis and E. citriodora were not affected. No significant differences in damage between different crown parts were observed.Treeswithageof1–3yrweredamagedmorethanthoseof age 4–6 yr. Pest infestation increased with an increase of L. invasa abundance but decreased with an increase of altitudes. Control efforts needs to focus on controlling the spread of the pest, using silvicultural methods and planting resistant Eucalyptus species

The effect of clay on the persistence of BTi toxicity against mosquito larvae in Morogoro, Tanzania IA

The article is a result of a project titled: The Impact and fate of pesticidal proteins from Bacillus thuringiensis spp. in tropical soils and waters as influenced by interactions with clays - MICROBE - (Project No. INCO no ERBICI8 CT 970135)Laboratory colonies of Anopheles gambiae and Culex quinquefasciatus were reared from parental larvae obtained from the Ifakara Health Research Centre and septic tanks ill Morogoro Municipality respectively. Water ponds (1M3 ) were constructed at selected sites and left open for mosquitoes to breed ill freely. Various concentrations of Bti crystals were-mixed with varying concentrations of clay and tested against third instar larvae of each species at various periods of time post-preparation. A total of 60 larvae (20 x 3) were exposed to each mixture in the laboratory, and each- experiment was replicated four times. Mortality rates were recorded after 241t. exposure. The observations revealed that for every concentration of Bti crystals used, the toxicity on both species of mosquitoes was less persistent in crystal/clay mixtures than in crystals alone. It was also shown that such persistence was much less in mixtures containing large concentrations of clay (5mg/ml) titan in those containing low concentrations (0.05 - 0.5 mg/ml) of clay. It wasfurther observed th at the toxicity against Culex and Anopheles larvae was more persistent in mixtures containing higher concentrations of Bti crystals (0.12 - 0.3 ug/ml) titan ill those containing low concentrations (0.03 - 0.06 ug/ml) of the toxin. Furthermore, it was observed that C. quinquefasciatus larvae succumbed to Bti crystal/clay mixtures for longer periods titan A. gambiae larvae. It was generally concluded that clays have 11 negative impact on the persistence of Bti toxicity against mosquito larvae and th at such impact is more significant in mixtures containing large concentrations clay. It was also concluded that despite the environmental friendliness of Bti, its applicability by communities is limited in view of its short persistence when it is adsorbed to tropical soils which are found in most natural mosquito breeding sites.European Union (EU

Preliminary assessment of forest structure, management and carbon stocking in Tanzania Miombo woodland

Wildfires are critical in miombo forests across the African continent causing loss of biodiversity, human properties and increasing climate change impacts. Within a broader project which seeks to develop a strategy to reduce wildfires in miombo woodlands of Tanzania, we report on the preliminary findings based on initial field data collected in situ to set a baseline for further work. The project covers three miombo biomes in three districts (Handeni, Kilosa and Kilwa) in Eastern Tanzania covering nine forest reserves managed under different authorities namely, central government, local districts and village communities. The aim of the current study were therefore, to describe species composition and structure of the forest communities, profile initial carbon stock in trees, herbaceous layer and soil within permanent survey plots, in effort to examine the potential of using fire reduction strategy as a potential tool of carbon sequestration in miombo woodlands.. The research team used permanent forest plots to collect vegetation and soil data. Simlarly available models were used to estimate carbon stocking. More than 200 species of trees and shrubs totaling 506 individual trees (dbh >4 cm) were recorded and Kilosa site contributed the largest proportion (40.7%) to the tree abundance total. This was followed closely by Kilwa (35.6%) and Handeni (20.7%). Species richness and diversity varied considerably within and between the study sites. Kilwa had the highest species richness and Handeni the lowest. Analysis of community assemblages revealed strongly distinct forest communities both at local and regional level between Kilwa and other sites. Carbon stocks in trees and soil were significantly different among sites and were higher than previously reported for other miombo woodland elsewhere in Tanzania. On the average tree carbon ranged from 21.42-44.12t/ha, the highest stock reported in Kilosa site due to assemblage of large trees. The general picture of carbon stock indicated that early burning is better for carbon storage than late burning or no burning. The lack of fire reduction strategy overrides the dynamics of forest stand structure and the potential for carbon sequestration by these forests as wildfires appear to be critical across the study area. There is dire need for a comprehensive strategy to reducing forest fires across the miombo biomes which together will help mitigate climate change impacts in Tanzania.CCIA

Assessment of fire prevalence and reduction strategies in Miombo woodlands of Eastern Tanzania

Tanzania Journal of Forestry and Nature Conservation, 84(1): 24-37An assessment of the proximate causes, effects and factors contributing to fire prevalence was conducted in three districts covered by miombo woodlands in Eastern Tanzania. Three miombo woodlands under different management regimes and governance structures (central government forest reserve, local government forest reserve and village land forest) each were investigated in Handeni, Kilosa and Kilwa districts. Data were collected from three villages selected in each District through household surveys, Participatory Rural Appraisal (PRA), interviews of key informants and field observations. The analysis of data involved content analysis for documentary materials, descriptive statistical analysis for household surveys and Chi square was used to test whether there were differences in responses of local communities across forest management regimes. Results indicate that the major five human activities contributing to fire prevalence across the miombo woodlands include farm preparation (34.1%), hunting (28.5%), arson (21.5%), livestock grazing (9.3%) and charcoal making (0.7%). The causes were fairly the same across forest management regimes. August, September and October were the peak fire months and they were not influenced by different management regimes but by geographical locations within Eastern Tanzania. Results further show that fires in miombo woodlands usually start inside the woodland (67.2%), around residential area (22.9%) and from farms (9.9%). The origin of fire inside the woodland becomes more serious because it combines the hunting, arson, livestock grazing and charcoal making which are usually done inside the woodland. Chi-square test indicates significant difference on origin of fires across the forest management regimes (χ² = 13.341 and p = 0.031). The local communities acknowledged fires having both positive and negative effects and these effects were the same across the management regimes. Further, across the surveyed villages, strong social ties existed between fires and the daily life of local communities. Poverty, ignorance, weak law enforcement and climatic factors were identified as underlying factors contributing to fire prevalence. Fire incidences are predicted to increase given the increasing climate change. Potential strategies to reduce fires incidence identified were awareness creation, law enforcement, making fire breaks, introduction of alternative income generating activities, and improving agriculture practises. Furthermore, the use of prescribed burning to reduce effects of late fires and developing fire management plans to enhance miombo woodland management are among the strategies worth consideration by the local communities

The importance of local forest benefits:valuation of non-timber forest products in the Eastern Arc Mountains in Tanzania

Understanding the spatial distribution of the quantity and value of Non-Timber Forest Product (NTFP) collection gives insight into the benefits that local communities obtain from forests, and can inform decisions about the selection of forested areas that are eligible for conservation and enforcement of regulations. In this paper we estimate transferable household production functions of NTFP extraction in the Eastern Arc Mountains (EAM) in Tanzania, based on information from several multisite datasets related to the behaviour of over 2000 households. These micro-level models can be used to predict the value of NTFP collection across a broader spatial scale. The study shows that the total benefit flow of charcoal, firewood, poles and thatch from the EAM to the local population has an estimated value of TSH 59 billion (USD 42 million) per year, and provides an important source of additional income for local communities, especially the poorest. We therefore argue that further restrictions on forest access to promote conservation will require additional policies to prevent a consequent increase in poverty, and an enforced trade-off between conservation and energy supply to rural and urban households

The importance of local forest benefits: Economic valuation of Non-Timber Forest Products in the Eastern Arc Mountains in Tanzania

Understanding the spatial distribution of the quantity and economic value of Non-Timber Forest Product (NTFP) collection gives insight into the benefits that local communities obtain from forests, and can inform decisions about the selection of forested areas that are eligible for conservation and enforcement of regulations. In this paper we estimate transferable household production functions of NTFP extraction in the Eastern Arc Mountains (EAM) in Tanzania, based on information from seven multi-site datasets related to the behaviour of over 2000 households. The study shows that the total benefit flow of charcoal, firewood, poles and thatch from the EAM to the local population has an estimated value of USD 42 million per year, and provides an important source of additional income for local communities, especially the poorest, who mainly depend on subsistence agriculture. The resulting map of economic values shows that benefits vary highly across space with population density, infrastructure and resource availability. We argue that if further restrictions on forest access to promote conservation are considered, this will require additional policies to prevent a consequent increase in poverty, and an enforced trade-off between conservation and energy supply to rural and urban households