Agro-ecological Zones Of Tanzania Research Articles

Multiple mycotoxin co-occurrence in maize grown in three agro-ecological zones of Tanzania

In this study, the co-occurrence of multiple mycotoxins in maize kernels collected from 300 households' stores in three agro-ecological zones in Tanzania was evaluated by using ultra high performance liquid chromatography/time-of-flight mass spectrometry (TOFMS) with a QuEChERS-based procedure as sample treatment. This method was validated for the analysis of the main eleven mycotoxins of health concern that can occur in maize: aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2), ochratoxin A (OTA), deoxynivalenol (DON), fumonisin B1 (FB1), fumonisin B2 (FB2), HT-2 toxin, T-2 toxin and zearalenone (ZEN). From each zone one major maize producing district for home consumption was chosen and 20 villages for each district were randomly selected for sampling. All mycotoxins of health concern, except for T-2 toxin, were detected in the maize samples. Particularly high levels of AFB1 (50%; 3–1,081 μg kg−1), FB1 (73%; 16–18,184 μg kg−1), FB2 (48%; 178–38,217 μg kg−1) and DON (63%; 68–2,196 μg kg−1) were observed. Some samples exceeded the maximum limits set in Tanzania for aflatoxins or in European regulations for other mycotoxins in unprocessed maize. Eighty seven percent of samples were contaminated with more than one mycotoxin, with 45% of samples co-contaminated by carcinogenic mycotoxins, aflatoxins and fumonisins. Significant differences in contamination pattern were observed among the three agro-ecological zones. The high incidence and at high levels (for some) of these mycotoxins in maize may have serious implications on the health of the consumers since maize constitute the staple food of most Tanzanian population. Effective strategies targeting more than one mycotoxin are encouraged to reduce contamination of maize with mycotoxins.

Reducing Impact of Land Degradation in Tanzania: Do Incentive Market Based Mechanisms Work for Sustainable Land Management?

Governments have traditionally relied on public budgets, bilateral and multilateral cooperation to support sustainable land management (SLM) activities. However, it is becoming evident that such support will not be sufficient neither can be sustainable to reverse land degradation, particularly in dry and degrading lands. Innovative mechanisms to encourage investments in SLM practices and to promote and enable the adoption of good practices in all land use sectors as a means to combat land degradation and address this challenge are needed. The paper addresses the hypothesis that, in Tanzania, impacts of land degradation can be reduced through the application of incentive market based mechanisms that could be implemented by the land users to ensure dual benefits i.e. environmental sustainability and improved human welfare of the land users. Key informants interviews and the desk reviews were the main methodological fronts used in gathering information. In Tanzania the practiced incentive market based mechanisms can be grouped into public payment systems, Open Trading under Regulation, Self Organized Private Deals, and Eco-Labeling of Products and Services. Components of these mechanisms have been tested in various agro-ecological zones in Tanzania and proved to be useful in the process of enhancing sustainable land management at the micro level. Observations therefore suggest that, some incentive market based mechanisms can work to reducing impact of land degradation at the micro level especially when they are related to improved purchasing power of the land users. In order to reduce the dependence of the governments and reduce donor syndrome in enhancing sustainable land management in Tanzania and elsewhere, there is a need of encouraging the use of incentive market based mechanisms that will have contributions to the welfare of the land users as well as contribution to the reduced land degradation.

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

This 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, and E. saligna was the least while E. grandis and E. citriodora were not affected. No significant differences in damage between different crown parts were observed. Trees with age of 1–3 yr were damaged more than those of 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.