Global sediment export based on InVEST Sediment Delivery Ratio model

Sediment runoff from disturbed coastal catchments is a major threat to marine ecosystems. Understanding where sediments are produced and where they are delivered enables managers to design more effective strategies for improving water quality. In this context, targeted restoration of degraded terrestrial areas provides opportunities to reduce land-based runoff from coastal areas and consequently foster coral reef conservation. To do this strategically, a systematic approach is needed to identify watersheds where restoration actions will provide the highest conservation benefits for coral reefs. This dataset is associated with the article "Global forest restoration opportunities to foster coral reef conservation", where we developed a systematic approach for identifying global forest restoration opportunities that would also result in large decreases in the flux of sediments to coral reefs. The dataset presented here consists of a global sediment export layer produced using the Sediment Delivery Ratio model of InVEST.

Methods
The sediment export per pixel is calculated using the soil erosion per pixel, as well the amount of sediment eroded from each pixel that actually reaches a stream or similar water course (Hamel et al. 2015). To model soil erosion, we used a high-resolution global potential soil erosion model developed by Borrelli et al. (2017) based on the revised universal soil loss equation (RUSLE; Renard et al. 1997), estimating soil erosion in each watershed. Sediment export was quantified using the InVEST sediment delivery model (Hamel et al. 2015), which implements a soil loss algorithm linked to the sediment connectivity algorithm proposed by Borselli et al. (2008). More details about the methodological approach can be found in Suárez-Castro et al. (2021).

Following Borrelli et al, we have capped the sediment export values to a maximum of 325 tonnes per hectare per year for pixels classified as barren, 250 tonnes per hectare per year for pixels classified as agricultural land and 50 tonnes per hectare per year for pixels classified as forest.