Browsing by Author "Mchelu, Hadija Ahmad"

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    The impact of the invasive tree cedrela odorota on the electric blue gecko (Lygodactylus williamsi) and its habitat (Pandanus rabaiensis) in Kimboza forest reserve, Tanzania
    (Elsevier B.V., 2022-01) Kilawe, Charles Joseph; Mchelu, Hadija Ahmad; Emily, Cosmas John
    Non-native plants are a major cause of habitat loss and fragmentation that lead to biodiversity loss. Geckos are particularly vulnerable to habitat alterations due to their small range and their restricted and specific terrestrial habits. However, our understanding of how introduced plants affect geckos, is poor. In this study, we investigate the potential effects of non-native and invasive neo-tropical tree Cedrela odorata on the critically endangered electric blue gecko, Lygodactylus williamsi, and its sole habitat, Pandanus rabaiensis. We used 107 square (10 m x 10 m) sample plots distributed systematically throughout the forest to assess the extent and effects of C. odorata on P. rabaiensis forest patches. We compared the abundance of L. williamsi on 125 P. rabaiensis trees growing in a mixture with C. odorata, native trees, and in pure stands and at three canopy cover categories (0–30%, >30–50%, and > 50%). We found an inverse relationship between the abundance of C. odorata trees (diameter at breast height (DBH)> 10 cm) and the abundance of P. rabaiensis. Spatially, the two trees dominated different parts of the forest. In contrast, the abundance of L. williamsi was not significantly affected by the presence of C. odorata. However, change in the canopy cover of the trees growing above the P. rabaiensis significantly affected the abundance of L. williamsi. The abundance of L. williamsi in a 0–30% cover was significantly higher than 30–50% and > 50% canopy covers. The findings of this study suggest that if left unmanaged, C. odorata could continue to take up the space that could be occupied by P. rabaiensis and other native plants, and thus limit the population size of an endangered species.
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    The effects of different grazing intensities on soil properties in Miombo Woodlands of Tanzania
    (Sokoine University of Agriculture, 2024-05) Mchelu, Hadija Ahmad
    This study was conducted at Miombo woodlands in Tanzania to enhance the sustainability of miombo woodlands in response to the increasing grazing pressure in miombo woodlands, driven by agricultural expansion, population growth, and rising demand for livestock products, has led to soil degradation, land scarcity, and socio-economic conflicts among land users. The study aimed to evaluate dynamics of selected soil physical and Soil organic carbon under different grazing intensities for sustainability of Miombo woodlands. The research used a purposive sampling and random sampling design. Grazing intensity was evaluated through two approaches: livestock stocking rates based on official records and a scoring method derived from field observations. Soil organic carbon (SOC) content was determined from topsoil samples collected from 188 plots whereas soil hydraulic conductivity (Kfs) and underground Water movement was estimated in 117 of these plots. Statistical analysis was carried out using R® software version 4.4.2, using Linear Mixed-Effects Models (LMM) and Gamma Generalized Linear Mixed-Effects Models (GLMM) with a random intercept. The results showed a slight agreement (k=0.14) between the stocking rate and scoring methods on classification of grazing intensities. Significant positive effects of increasing grazing intensity GI were observed on bulk density (BD) and preferential flow (P<0.001), while significant negative effects (P<0.001) were observed on SOC, (Kfs), percentage dye cover, and uniform infiltration flow. The mean SOC ranged from 2.38 ± 0.84% under light grazing intensity to 1.42 ± 0.75% under high grazing intensity. Kfs showed a mean range of 100.08-± 65.56 mmhr-1 under light grazing intensity to 27.28 ± 22.99 mmhr-1 under high grazing intensity, while BD ranged from 1.64 ± 0.12 gcm-3 under high grazing intensity to 1.34 ± 0.17 g cm-3 under light grazing intensity. The study recommends developing and implementing proper sustainable livestock management practices made to the specific conditions of Miombo ecosystems. Adhering to sustainable