Browsing by Author "Moe, Stein R."

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Bird flight initiation distances in relation to distance from human settlements in a Tanzanian floodplain habitat
(Springer, 2014-09-26) Bjørvik, Linn M.; Dale, Svein; Hermansen, Gudmund H.; Munishi, Pantaleo K. T.; Moe, Stein R.
Human activity affects wildlife in many ways, but there have been few studies of how wildlife behav- ioural responses to human disturbance vary with distance from centres of human activity. Theory suggests that fear responses may be either higher in areas with high distur- bance (disturbance avoidance) or lower in such areas (e.g. due to habituation). We used flight initiation distance (FID) to study how fear responses of 16 bird species varied with distance from villages (range 0.1–11.6 km) within the Ramsar site of Kilombero Valley, Tanzania. A linear model indicated that FID was not related to distance from villages, but varied between habitats. However, a piecewise linear model (linear response up to 2 km, flat response [2 km from villages) provided a better fit and suggested that there may be a small decrease in FID close to human settlements, in particular for the Common Bulbul (Pycn- onotus barbatus) and a few other species, although the majority of species still showed little change in FID with distance from human settlements. Our results suggest that a few species may respond to human disturbance with a decreased FID, whereas the majority of species showed little variation in FID in relation to distance from human settlements, and may therefore be negatively affected by increasing frequency of human disturbance.
Relationships between tree species richness, evenness and aboveground carbon storage in montane forests and miombo woodlands of Tanzania
(Elsevier, 2014-12-05) Shirima, Deo D.; Totland, Ørjan; Munishi, Pantaleo K.T.; Moe, Stein R.
Understanding how carbon storage and tree diversity are related in forests and woodlands is crucial for a sustainable flow of ecosystem goods and services. The goal of this study was to determine how tree species richness, evenness and environmental factors influence aboveground live tree carbon stocks (AGC) in two tropical vegetation types in Tanzania. We surveyed trees and sampled soil from 222 vegetation plots (20 m × 40 m) in montane forests (n = 60) and miombo woodlands (n = 162). We used a multimodel inference approach to determine how AGC related to tree species richness, evenness and environmental factors, and linear mixed effect models to test the role of tree sizes on the AGC-richness and evenness associations. AGC were related unimodally to tree species richness and evenness in the montane forest. Likewise, AGC in the miombo woodlands was positively related to tree species richness. AGC from small trees were related unimodally to tree species richness in both vegetation types. Apparently the AGC had both monotonically increasing and decreasing associations with all abiotic environmental factors in both vegetation types. We emphasize that both tree size, number of multi-stemed trees and environmental factors have an important role in determining how AGC are related to richness and evenness. Finally, management of montane forests and miombo woodlands of Tanzania to enhance ecosystem benefit, such as AGC, will require strategies that consider tree sizes, tree species richness, evenness and underlying environmental and disturbance factors.