Latitude and community robustness primarily predict invasion probability of three widespread, invasive plants in Mississippi lakes.

Freshwater ecosystems are critically important ecologically and the majority of surface freshwater in many states is found in small lakes. Despite their importance and prevalence, small lakes receive lower research and management effort than larger reservoirs. Aquatic macrophytes are essential components of small lake ecosystems as they are primary producers that provide animal food and habitat, and substantially affect water quality. In Mississippi, small lakes are important natural resources for humans and wildlife, but prior to 2017, no statewide survey efforts were undertaken to survey the aquatic macrophyte communities of small Mississippi lakes. The objective of this study was to use macrophyte community data from state-wide lake surveys since 2017 to determine which landscape factors best predict invasion probability of three aquatic invasive plants: Alternanthera philoxeroides, Panicum repens, and Triadica sebifera. Surveys of small Mississippi lakes were conducted in the summers of 2017, 2019, 2020, 2022, and 2023. Surveys were conducted using littoral point sampling which yielded presence/absence data of macrophyte species in the littoral zone of lakes. Three plant community metrics - a-diversity, point richness, and littoral fraction (the vegetated proportion of the littoral zone) - were combined into a principal component we refer to as "robustness". Robustness and four other environmental and geographic factors (latitude, longitude, lake area, and secchi depth) were used as factors to predict presence of the three target invasive species. Predictors were fit to response variables using logistic generalized linear models with logit functions. Best-fit models for presence of the three target invasives included only robustness and latitude as predictors. These models help explain what characteristics increase the risk of invasion by common aquatic invasive plants. [ABSTRACT FROM AUTHOR]