Irizarry Brugman, Edwin

Profile Picture

Filters

20221
Reset filters

Settings

Citations

Publication Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    Publication
    Soil and sedimentation dynamics of a widespread shallow landsliding event in a tropical montane setting
    (2022-12-13) Irizarry Brugman, Edwin; Hughes, K. Stephen; College of Arts and Sciences - Sciences; Matos, Manuel; López Venegas, Alberto; Department of Geology; Malik, Sudhir
    Rainfall-induced landslides occur predominantly because of intense tropical cyclones in Puerto Rico. The purpose of this study was to explore the role of specific soil attributes in mass wasting, the negative feedback loop between erosion and chemical weathering, and to track the sedimentation record of widespread landslides triggered by Hurricane María (2017) in a critical reservoir of the island. Quantitative modeling and field measurements helped the quantification of extreme atmospheric events on weathering and sedimentation on the island. Principal Component Analysis was used to explore soil attributes that are common in soil map units that have been determined to be prone to rainfall-induced landslides. The analysis results do not identify a unique or uniform combination of soil attributes that correlate with soils vulnerable to mass wasting in Puerto Rico, but slight trends influenced by clay content at 0-60 cm depth are noteworthy. These trends, while not conclusive, suggest that concentrations of clays at key soil depths could be important for shallow landsliding on the island. The relationship between landslide induced erosion and chemical weathering was studied in the Río Grande de Arecibo catchment. Sub-basins with higher landslide densities were expected to have higher solute concentrations. The results from this study differ from these concepts and instead suggest that the landscape is not supply-limited, but kinetically controlled. A bathymetric survey of Lago Dos Bocas was completed in 2021 to quantify the change in water storage capacity after the widespread landsliding in 2017. The survey results show that the storage capacity of the reservoir is approximately 13.35 million cubic meters (Mm 3 ), a storage loss of 64% from its original capacity in 1942. Using a capacity loss rate based on previous bathymetric surveys, a sediment “surplus” of approximately 2 Mm 3 is associated with Hurricane María. This volume represents approximately 18 years of 21 st century background sedimentation.