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Matthew Richardson

Publications and source records attributed to Matthew Richardson.

2 recordsLinked to original sources

An expert elicitation to inform coastal management decision-making for mitigating future hazards

A scientific expert elicitation was conducted to address the feasibility of restoring coastal environments in response to future hazards to best meet management objectives. Subject matter experts produced probabilistic estimates of coastal change metrics used to evaluate decision objectives and alternatives informed by a stakeholder advisory group. Changes in salt marsh extents, storm surge flooding and barrier island morphology by the year 2050 were estimated for three scenarios of management actions (no action, interior headland restoration, beach and dune nourishment), while also considering the effects of future sea level rise (SLR). Collectively the participants were confident in their expectations of increased storm surge flooding with SLR, regardless of management interventions. Estimates of marsh response had large uncertainty, but experts generally hypothesized that marsh area would decrease with increasing SLR if no action was taken, especially in areas already experiencing marsh deterioration. There was agreement that dune heights and barrier island widths would decrease with SLR if no action was taken. Experts felt that beach and dune nourishment may reduce the amount of erosion under future SLR. All experts recognized the dynamic effects of SLR and feedback between bio-geo-physical processes that govern coastal systems. Participants agreed that size and location of management actions were important factors for influencing the coastal response. Expert elicitation is novel in the context of coastal management decision making and can be a useful tool for informing future scientific needs and providing rapid results to end users to inform reallocation of resources surrounding research and application.

Alabama, Mississippi

Extensive regional variation in the phenology of insects and their response to temperature across North America

Climate change models often assume similar responses to temperatures across the range of a species, but local adaptation or phenotypic plasticity can lead plants and animals to respond differently to temperature in different parts of their range. To date, there have been few tests of this assumption at the scale of continents, so it is unclear if this is a large-scale problem. Here, we examined the assumption that insect taxa show similar responses to temperature at 96 sites in grassy habitats across North America. We sampled insects with Malaise traps during 2019–2021 ( N = 1041 samples) and examined the biomass of insects in relation to temperature and time of season. Our samples mostly contained Diptera (33%), Lepidoptera (19%), Hymenoptera (18%), and Coleoptera (10%). We found strong regional differences in the phenology of insects and their response to temperature, even within the same taxonomic group, habitat type, and time of season. For example, the biomass of nematoceran flies increased across the season in the central part of the continent, but it only showed a small increase in the Northeast and a seasonal decline in the Southeast and West. At a smaller scale, insect biomass at different traps operating on the same days was correlated up to ~75 km apart. Large-scale geographic and phenological variation in insect biomass and abundance has not been studied well, and it is a major source of controversy in previous analyses of insect declines that have aggregated studies from different locations and time periods. Our study illustrates that large-scale predictions about changes in insect populations, and their causes, will need to incorporate regional and taxonomic differences in the response to temperature.

Ecology