Flooding is a major disturbance that impacts aquatic ecosystems and the ecosystem services that they provide. Predicted increases in global flood risk due to land use change and water cycle intensification will likely only increase the frequency and severity of these impacts. Extreme flooding events can cause loss of life and significant destruction to property and infrastructure, effects that are easily recognized and frequently reported in the media. However, flooding also has many other effects on people through freshwater aquatic ecosystem services, which often go unrecognized because they are less evident and can be difficult to evaluate. Here, we identify the effects that small magnitude frequently occurring floods (< 10-year recurrence interval) and extreme floods (> 100-year recurrence interval) have on ten aquatic ecosystem services through a systematic literature review. We focused on ecosystem services considered by the Millennium Ecosystem Assessment including: (1) supporting services (primary production, soil formation), (2) regulating services (water regulation, water quality, disease regulation, climate regulation), (3) provisioning services (drinking water, food supply), and (4) cultural services (aesthetic value, recreation and tourism). The literature search resulted in 117 studies and each of the ten ecosystem services was represented by an average of 12 ± 4 studies. Extreme floods resulted in losses in almost every ecosystem service considered in this study. However, small floods had neutral or positive effects on half of the ecosystem services we considered. For example, small floods led to increases in primary production, water regulation, and recreation and tourism. Decision-making that preserves small floods while reducing the impacts of extreme floods can increase ecosystem service provision and minimize losses.
Bibliographical noteFunding Information:
We greatly appreciate all the support received during the American Geophysical Union (AGU) Chapman Conference on Extreme Climate Event Impacts on Aquatic Biogeochemical Cycles and Fluxes held in San Juan, Puerto Rico in January 2017 which facilitated these discussions. This work was supported by Canada?s Natural Science and Engineering Research Council (NSERC) strategic network Canadian FloodNet (Grant no.: NETGP 451456) and an NSERC Discovery grant to MAX, as well as part of the National Science Foundation (NSF) Projects DEB 1119704, 0812913, 1652594, OCE 1706009, and the Defense Coastal/Estuarine Research Program (DCERP) Project Number: RC-2245. Responsible Editor: Sujay Kaushal.
- Ecological functions
- Ecosystem services
- Extreme floods
- High discharge
- Natural floods