Abstract:
1. Worldwide bees provide an important ecosystem service of plant pollination.
Climate change and land-use
changes are among drivers threatening bee survival
with mounting evidence of species decline and extinction. In developing countries,
rural areas constitute a significant proportion of the country's land, but information
is lacking on how different habitat types and weather patterns in these
areas influence bee populations.
2. This study investigated how weather variables and habitat-related
factors influence
the abundance, diversity, and distribution of bees across seasons in a farming
rural area of Zimbabwe. Bees were systematically sampled in five habitat types
(natural woodlots, pastures, homesteads, fields, and gardens) recording ground
cover, grass height, flower abundance and types, tree abundance and recorded
elevation, temperature, light intensity, wind speed, wind direction, and humidity.
Zero-inflated
models, censored regression models, and PCAs were used to understand
the influence of explanatory variables on bee community composition,
abundance, and diversity.
3. Bee abundance was positively influenced by the number of plant species in flower
(p < .0001). Bee abundance increased with increasing temperatures up to 28.5°C,
but beyond this, temperature was negatively associated with bee abundance.
Increasing wind speeds marginally decreased probability of finding bees.
4. Bee diversity was highest in fields, homesteads, and natural woodlots compared
with other habitats, and the contributions of the genus Apis were disproportionately
high across all habitats. The genus Megachile was mostly associated with
homesteads, while Nomia was associated with grasslands.
5. Synthesis and applications. Our study suggests that some bee species could become
more proliferous in certain habitats, thus compromising diversity and consequently
ecosystem services. These results highlight the importance of setting
aside bee-friendly
habitats that can be refuge sites for species susceptible to land-use changes.
