農耕地造成の草地における植物と送粉者の相互作用

Newly established grasslands and flower strips on arable land aim to counteract ongoing biodiversity loss, often specifically designed to promote pollinators. However, their effectiveness in supporting diverse and stable plant-pollinator networks remains not fully understood. We compared plant-pollinator interactions in newly established grasslands, 5-6 years after sowing on arable land, and old, permanent grasslands in a Central European agricultural region. Across 1095 recorded interactions, we found significantly higher pollinator visitation frequency and diversity per plant species in newly established grasslands than in old grasslands, particularly for solitary bees and syrphids. Network analyses revealed comparable nestedness and specialization in newly established grasslands and old grasslands. Distinct plant family and color preferences emerged among pollinator groups, with bumble bees favoring Fabaceae, syrphids visiting especially Apiaceae and Rubiaceae, and butterflies preferring Fabaceae and Caryophyllaceae. Several generalist pollinators and key plant species played central roles in both grassland types, highlighting their importance for network connectivity. Our findings suggest that carefully designed new grasslands can support diverse plant-pollinator networks and contribute meaningfully to biodiversity conservation and ecosystem services in agricultural landscapes.