Julienne E. Nesmith

University of Florida | UF · Department of Geography

Models of tree–grass coexistence in savannas make different assumptions about the relative performance of trees and grasses under wet vs dry conditions. We quantified transpiration and drought tolerance traits in 26 tree and 19 grass species from the African savanna biome across a gradient of soil water potentials to test for a trade‐off between wa...

Purpose Soil moisture availability is a key driver of the relative abundance of trees and grasses in savannas. Fine root morphology influences water acquisition and transport, yet differences in fine root traits between trees and grasses have not been comprehensively quantified across an entire suite of coexisting tree and grass species. Methods We...

Vegetation states in savannas are highly sensitive to tree growth rates, which determine whether individual trees can “escape” periodic disturbances. Resprouting trees have lopsided shoot:root ratios and are often multi‐stemmed, and these variables can modify post‐disturbance growth rates and therefore the probability of escape. To date, few studie...

PREMISE: Belowground functional traits play a significant role in determining plant water use strategies and plant performance, but we lack data on root traits across communities, particularly in the tropical savanna biome, where vegetation dynamics are hypothesized to be strongly driven by tree–grass functional differences in water use. METHODS: W...

Climate change and non-native invasive species are two predominant drivers of global environmental change, yet little is known about how they might interact to affect native communities and ecosystems. Drought and plant invasions are intensifying in ecosystems worldwide, including ecologically and economically important pine forests of the southeas...

Abiotic global change drivers affect ecosystem structure and function, but how they interact with biotic factors such as invasive plants is understudied. Such interactions may be additive, synergistic, or offsetting, and difficult to predict. We present methods to test the individual and interactive effects of drought and plant invasion on native e...

Abstract Background/Questions/Methods Plant invasions and climate change, such as enhanced frequency and intensity of drought, are primary environmental threats, yet few studies have evaluated how they interact to affect ecosystems. Drought stress may have synergistic effects with invasion, further suppressing native plant species. Alternatively, i...

Propagule pressure is commonly considered a primary driver of invasive plant establishment and spread. However, the physical size or condition (i.e., quality) of propagules may also affect establishment, particularly under unfavorable habitat conditions such as low light environments. We used an outdoor mesocosm experiment to test the relative cont...