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Tropical ecosystems face escalating global change. These shifts can disrupt tropical forests' carbon (C) balance and impact root dynamics. Since roots perform essential functions such as resource acquisition and tissue protection, root responses can inform about the strategies and vulnerabilities of ecosystems facing present and future global changes. However, root trait dynamics are poorly understood, especially in tropical ecosystems. We analyzed existing research on tropical root responses to key global change drivers: warming, drought, flooding, cyclones, nitrogen (N) deposition, elevated (e) CO2, and fires. Based on tree species‐ and community‐level literature, we obtained 266 root trait observations from 93 studies across 24 tropical countries. We found differences in the proportion of root responsiveness to global change among different global change drivers but not among root categories. In particular, we observed that tropical root systems responded to warming and eCO2 by increasing root biomass in species‐scale studies. Drought increased the root: shoot ratio with no change in root biomass, indicating a decline in aboveground biomass. Despite N deposition being the most studied global change driver, it had some of the most variable effects on root characteristics, with few predictable responses. Episodic disturbances such as cyclones, fires, and flooding consistently resulted in a change in root trait expressions, with cyclones and fires increasing root production, potentially due to shifts in plant community and nutrient inputs, while flooding changed plant regulatory metabolisms due to low oxygen conditions. The data available to date clearly show that tropical forest root characteristics and dynamics are responding to global change, although in ways that are not always predictable. This synthesis indicates the need for replicated studies across root characteristics at species and community scales under different global change factors. [ABSTRACT FROM AUTHOR]

Seasonal floodplain wetlands occur throughout the Piedmont Region of South Carolina, providing a plethora of ecosystem services. As a result of extensive soil erosion during the agricultural period from mid-1700s until mid-1900s, Piedmont floodplains have accreted significantly, altering their natural flood regime. The purpose of this study was to better understand the impacts of land use change and seasonality on the hydrology of two adjacent, seasonal floodplain wetlands. This was done by evaluating water levels in each wetland for a period of twelve months using wells, monitoring groundwater through a piezometer, characterizing sediments from 0 to 21cm, and comparing rainfall events to the Lawson's Fork Creek stream gage and wetland water levels. It was found that the type and intensity of rainfall events were key components driving wetland water level changes during each season. During storm events, the wetlands aided in flood control; results show that they may be hydraulically connected during intense overbank flooding events. Groundwater was not found to recharge the surface during dry periods, as proposed, which could be due to low sample size and only one piezometer. The results of this study demonstrate the need for long term hydrological research of small seasonal wetlands in order to better protect and manage the ecological services they provide. [ABSTRACT FROM AUTHOR]