Agricultural intensification has increased crop yields, but has also negatively influenced the flow of ecosystem services provided by beneficial organisms that support production. Management of ecological services needs to be effectively combined with external inputs such as insecticides and fertilizers to enhance and stabilize yields. This requires an understanding of factors that regulate the numbers of beneficial and pest organisms at the field and landscape scale.
Using widespread crops as model systems I am interested to investigate how local and landscape management influence ecosystem services (pollination and biological control) as well as pest density and resistance to pesticide.
At the landscape scale my work has focused on how land-use intensification impacts natural enemies and pollinators communities and diversity. Another aspect of my research investigates whether field scale management, in particular agricultural fertilization and diversification, could be managed to strengthen ecosystem services.
Red Clover project (2018 - 2020): Investigate the impact of mass flowering crops on pollinator communities and bumblebee pathogens.
Broad Bean project (2020 - 2021): Consequences of floral herbivory by Bruchus on pollination services in faba beans.
Riggi, L. & Bommarco R. 2019. Subsidy type and quality determine direction and strength of trophic cascades in arthropod food webs in agroecosystems. Journal of Applied Ecology. 56 (8)
Riggi, L.G., Vesna, G., Rusch A., Malsher G., Ekbom B., Bommarco R. 2017. Pollen beetle mortality is increased by ground-dwelling generalist predators but not landscape complexity. Agriculture, Ecosystems and Environment, 250: 133-142.
Gagic, V., Riggi, L.G., Ekbom, B., Malsher, G., Rusch, A. and Bommarco, R., 2016. Interactive effects of pests increase seed yield. Ecology and Evolution, 6(7): 2149–2157.
Riggi L, V Gagic, R Bommarco, B Ekbom. 2016. Insecticide resistance in pollen beetles over 7 years - a landscape approach. Pesticide Management Science, 72(4): 780-6.
Riggi, L., Veronesi, M., Goergen, G., MacFarlane, C., Verspoor, R.L. 2016. Observations of entomophagy across Benin - practices and potentials. Food Security, 8(1):151-152.
Verspoor, R., Jacobsen, M., Riggi, L., Veronesi, M., 2016. Bugs for Life bites back: Edible insects in northern Benin. Bulletin of the Royal Entomological Society, Antenna 40(2):67-71.
Damon, A., Hernández-Ramírez, H., Riggi, L., et al. 2012. Pollination of euglossinophylic epiphytic orchids in agroecosystems and forest fragments in southeast Mexico. European Journal of Environmental Sciences. 2 (1): 5-14.
Riggi, L. & Berggren, Å. Small field islands systems include a large proportion of the regional orthopteran species pool in arable landscapes. Re-submitted after major revisions to the Journal of Insect Conservation on 1st of April 2020.
Bugs for Life Charity: https://www.bugsforlife.com/