Data from: Agricultural specialisation increases the vulnerability of pollination services for smallholder farmers

Smallholder farms make up 84% of all farms worldwide and feed two billion
people. These farms are heavily reliant on ecosystem services and
vulnerable to environmental change, yet under-represented in the
ecological literature. The high diversity of crops in these systems makes
it challenging to identify and manage the best providers of an ecosystem
service, such as the best pollinators to meet the needs of multiple crops.
It is also unclear whether ecosystem service requirements change as
smallholders transition towards more specialised commercial farming – an
increasing trend worldwide. Here, we present a new metric for predicting
the species providing ecosystem services in diverse multi-crop farming
systems. Working in 10 smallholder villages in rural Nepal, we use this
metric to test whether key pollinators, and the management actions that
support them, differ based on a farmers’ agricultural priority (producing
nutritious food to feed the family versus generating income from cash
crops). We also test whether the resilience of pollination services
changes as farmers specialise on cash crops. We show that a farmers’
agricultural priority can determine the community of pollinators they rely
upon. Wild insects including bumblebees, solitary bees, and flies provided
the majority of the pollination service underpinning nutrient production,
whilst income generation was much more dependent on a single species - the
domesticated honeybee Apis cerana. The significantly lower diversity of
pollinators supporting income generation leaves cash crop farmers more
vulnerable to pollinator declines. Regardless of a farmers’ agricultural
priority, the same collection of wild plant species (mostly herbaceous
weeds and shrubs) were important for supporting crop pollinators with
floral resources. Promoting these wild plants is likely to enhance
pollination services for all farmers in the region. Synthesis and
applications: We highlight the increased vulnerability of pollination
services when smallholders transition to specialised cash crop farming and
emphasise the role of crop, pollinator, and wild plant diversity in
mitigating this risk. The method we present could be readily applied to
other smallholder settings across the world to help characterise and
manage the ecosystem services underpinning the livelihoods and nutritional
health of smallholder families.