POLLINATE - Can biochar-engineered soils boost habitat use for pollinators in Portuguese sown biodiverse pastures?
POLLINATE’s pioneer concept and approach was designed to evaluate if, and how, engineering soil conditions through biochar may improve ecosystem characteristics that are directly linked to pollinator habitat use in pastures (as proof-of-concept)
Background
Unsustainable soil management has led to well-documented declines in abundance and diversity of flora and increased pesticide usage, leading to a global overwhelming loss of habitat use by pollinators in intensive grasslands (pastures). Pastoral systems are increasingly challenged in their efforts to secure productivity and livestock, while supporting other ecosystem services, such as pollination. But there is no reason for these to be mutually exclusive. So far, very few studies used soil engineering strategies to improve pollinator habitat in grasslands, despite results from pot experiments looking promising. The literature suggests that it is possible to enhance pollinator habitat use through soil amendment with organic/inorganic substrates, leading to improved floral production, visual characteristics and pollen/nectar abundance. Also, insect abundance and diversity were positively correlate with improved soil structure, moisture and nutrient contents upon soil fertilization, with increased flower visitation rates and pollen protein contents. We anticipate biochar to have comparable outcomes for pollinators.
Impact
we hypothesise that biochar can simultaneously improve: a) floral visual (e.g. nº, size, colour) and olfactory (volatile profiles) display that is linked to attraction cues; b) pollen/nectar abundance and quality (e.g. nutritional value, reduced pesticide content); and c) burrowing/nesting conditions for ground-nesting communities (e.g. reduced soil compaction and resistance to penetration).
At the time of writing, a Scopus search found no scientific publications with biochar AND pollinators in keywords/title/abstract. But
while it is a novel, timely and exciting concept, it is not topic for an exploratory project per se, since there is already evidence that biochar has the potential to achieve this goal. In fact, a pot-based fertilization study was first to report increased flower visitation by pollinators in biochar-amended soil. But the extent, and through which abiotic mechanisms, biochar can boost pollinator habitat use in pastures remains largely a knowledge gap. POLLINATE outcomes are expected to benefit research, stakeholders and society to different extents, thus directly and indirectly, contributing to UN sustainability targets nº15,13,17.