Final Report: Identifying the Risk of Runoff and Erosion in Hawaiʻi’s National Parks
Dates
Publication Date
2021-10-01
Citation
Lucas B Fortini, and Lauren Kaiser, 2021-10-01, Final Report: Identifying the Risk of Runoff and Erosion in Hawaiʻi’s National Parks: .
Summary
Changes in land cover can alter soil infiltration capacity and increase runoff and erosion, negatively affecting national parks and other public lands across Hawaiʻi. Reduced infiltration, the soil’s ability to allow water through it, within these lands may lead to serious consequences including terrestrial habitat damage by erosion, aquatic habitat damage by sedimentation, and downstream damage by flooding due to storm flows from overland flow, or runoff. To help understand potential damage, we calculated the probability of rainfall runoff across the Hawaiian landscape. By characterizing soil infiltration based on different land cover types (bare soil, grasses, and woody vegetation) and comparing them to large rainfall events, we [...]
Summary
Changes in land cover can alter soil infiltration capacity and increase runoff and erosion, negatively affecting national parks and other public lands across Hawaiʻi. Reduced infiltration, the soil’s ability to allow water through it, within these lands may lead to serious consequences including terrestrial habitat damage by erosion, aquatic habitat damage by sedimentation, and downstream damage by flooding due to storm flows from overland flow, or runoff. To help understand potential damage, we calculated the probability of rainfall runoff across the Hawaiian landscape. By characterizing soil infiltration based on different land cover types (bare soil, grasses, and woody vegetation) and comparing them to large rainfall events, we were able to map the potential risk of runoff across the main Hawaiian Islands. While smaller runoff analyses have been done for specific watersheds, no previous work has taken this landscape level approach. These calculations of potential runoff risk were completed for current climatic conditions as well as a future climate scenario. Not only can these runoff risk maps be used for current management planning purposes, the future scenario can be applied to proactively address further potential damage from runoff. This information is pertinent to federal, state, and non-governmental land managers and city planners alike to understand how changes in land cover can influence runoff and erosion, which can be both ecologically costly and result in infrastructure damage. Furthermore, in the process of exploring available climate datasets for this runoff analysis, we developed multiple climate products that characterize current and future climate scenarios for Hawaiʻi. These new datasets provide a broader range of potential climate scenarios than currently available, and will be useful for efforts to understand and prepare for future climate shifts across Hawaiʻi.
