The FloRes Database: A floral resources trait database for pollinator habitat-assessment generated by a multistep workflow

Background The decline of pollinating insects in agricultural landscapes
proceeds due to intensive land use and the associated loss of habitat and
food sources. The feeding of those insects depends on the spatial and
temporal distribution of nectar and pollen as food resources. Hence, to
protect insect biodiversity a spatio-temporal assessment of food quantity
of their habitats is necessary. Therefore, sufficient data on traits of
floral resources are required. New information Because floral resources’
traits of plants are important to quantify food availability, we present
two databases, the FloRes Database (Floral Resources Database) and the raw
database, where FloRes was derived from. Both databases contain the plant
traits (1) flowering period, (2) floral-unit density per day, (3) nectar
volume per floral unit per day, (4) sugar content per floral unit, (5)
sugar concentration in nectar, (6) pollen mass or volume per floral unit
and per day, (7) protein content of pollen and (8) corolla depth. All
traits are sampled from literature and online databases. The raw database
consists of 702 specified plant species, 138 unspecified species 37
species (spec., sp), 22 species pluralis (spp) and for 79 only the genus
was identified) and two species complexes (agg.). Those 842 taxa belong to
488 genera and 102 families. Finally, only 27 taxa have a complete set of
traits, too less for a sufficient assessment of spatio-temporal
availability of floral food resources. Because information of floral
resources is scattered throughout many publications with different units,
we also present our multistep workflow implemented in five consecutive
R-scripts. The multistep workflow standardizes the trait units of the raw
database to comparable entities with identical units and aggregates them
on a reasonable taxonomic level into the second application database, the
FloRes Database. Finally, the FloRes Database contains aggregated
information of traits for 42 taxa and, when corolla depth is excluded, for
70 taxa. This is the first attempt to gather these eight traits from
different literature sources in one database with a multistep workflow.
The publication of the multistep workflow enables the users to extend the
FloRes Database on their own demands with other literature data or newly
gathered data to improve the quantification of food resources. Especially,
the combination of pollen, nectar, and open flowers per square meter is,
as far as we know, a novelty. The FloRes Database can be used to evaluate
the quantity of food-resource habitats available for pollinators, e.g., to
compare seed mixtures of agri-environmental measures, such as flower
strips, considering flower phenology on a daily basis.