Global opportunity areas for nature-based solutions to reduce risks to infrastructure

This dataset identifies areas where nature-based solutions (NbS) in the form of viable tree planting have the potential to reduce risk to infrastructure, through flood reduction, coastal erosion control and landslide risk reduction. The outputs are a series of maps showing potential opportunity areas for revegetation with trees at a 250m resolution globally, with their associated costs, potential biodiversity and carbon co-benefits, and identified baseline (pre-intervention) risks to road and rail infrastructure posed by landslides, river flooding and coastal flooding.

As a global scale assessment, making use of globally consistent and publicly available datasets, there are limitations on the accuracy of the information provided at the fine spatial scale. These results are targeted at the initial project screening stage, to select between broad areas and understand the regional  context. After this initial screening, prospective users should follow up with more detailed studies, drawing on best available local information to develop an in depth understanding of the potential costs and benefits of an individual project.

The work covers three categories of risk reduction:

Mangrove restoration for reduction of coastal erosion. This is divided into 3 categories, areas with accreting shorelines, areas with neutral to slowly retreating shorelines and areas with fat retreating shorelines, with respective increasing costs in relation to coastal management;

Tree restoration for the reduction of landslide risk. These are divided into two categories, areas which replace crops (since in some cases the landslide risk may be exacerbated by agricultural activities, and this costly option might be appropriate) and other areas. An additional category where the ground is currently bare is also highlighted. This is a rare case, and may indicate that there is insufficient soil for tree growth;

Sub basin level plantings for potential flood risk reduction. Here sub basins with risk of flooding are identified, and all potential tree plantings in the sub basin flagged. A variety of different planting approaches can be used to manage flooding, but all require a significant extent of plantings to make a difference. Due to the complexity of river flow, and limited evidence, no downstream effects outside the immediate catchment are considered.

Theme
File
Description

Opportunity Areas
ManRestorClass_9s.tif 

Potential mangrove restoration areas for coastal flooding risk reduction.

Categorical values of shoreline dynamics: 

1: Accreting (expanding) shorelines. Ideal. 

2: Static to moderate retreating shorelines. Less than ideal. 

3: Fast retreating shorelines. Expensive to restore, may be worth considering if coastal management is applied to block fill an otherwise appropriate area. 

Opportunity Areas
G_LandslideNbS_123_9s.tif 

Potential slope vegetation areas for landslide risk reduction. Currently non-woodland areas which could be restored to woodland with slope 8-36 degrees.  

Categorical values of current land-use:  

1: Other 

2: Crops  

3: Bare Ground

Opportunity Areas
G_PotentialNonCoastalTreeNBS_9s.tif 

Potential restoration areas for river flooding risk reduction. Currently non-woodland, non-cropped areas, away from the coast, which could be restored to woodland as part of a catchment restoration programme. 

Categorical (binary) value of suitability: 

1: Suitable 

Planting costs and benefits
G_BioBenefit_9s.tif
Biodiversity benefit (this is a relative number derived from the Biodiversity Habitat Index as the slope of the species area curve to give a relative prioritisation). The per grid cell benefits do not accrue, rather best represented by the MEAN of the slope for all grid cells in a project. (Note that for really very big clusters, the restoration may be of such a scale that there would be interactions between grid cells which we should ignore for this project). 

Planting costs and benefits
G_CarbonBenefit_9s.tif
Additional carbon of mature forest after nominal 50 years (tonnes per hectare) 

Planting costs and benefits
G_PlantingCost_9s.tif
Native planting costs (2020 US dollars per hectare of restoration) 

Planting costs and benefits
ManPlantCost_9s.tif
Native planting costs for mangroves (2020 US dollars per hectare of restoration) 

Planting costs and benefits
G_RegenCost_9s.tif
Natural regeneration costs (2020 US dollars per hectare of restoration) 

Planting costs and benefits
ManRegenCost_9s.tif
Natural regeneration costs for mangroves (2020 US dollars per hectare of restoration) 

Opportunity areas (vector)
landslide_slope_vegetation_with_EAD.geoparquet 
Opportunity areas as MultiPolygon patches with costs and benefits attributed, including road and rail EAD (Expected Annual Damages) from landslide hazard 

Opportunity areas (vector)
landslide_slope_vegetation_with_EAD_grouped_gt0.gpkg

Opportunity areas grouped to merge all patches (of the same current land-use) within each HydroBasins level 12 sub-basin (Lehner and Grill 2013).

EAD aggregated to min/mean/max across model ensembles 

Filtered to exclude areas with a maximum EAD of less than 1 USD 

Opportunity areas (vector)
mangrove_with_EAD.geoparquet
Opportunity areas with costs and benefits attributed, including road and rail EAD (Expected Annual Damages) from coastal flooding hazard

Opportunity areas (vector)
mangrove_with_EAD_grouped_gt0.gpkg

Opportunity areas grouped to merge all patches (of the same shoreline dynamics) within each HydroBasins level 12 sub-basin (Lehner and Grill 2013). 

EAD aggregated to min/mean/max across model ensembles 

Filtered to exclude areas with a maximum EAD of less than 1 USD

Opportunity areas (vector)
river_basin_afforestation_with_EAD.geoparquet
Opportunity areas with costs and benefits attributed, including road and rail EAD (Expected Annual Damages) from river flooding hazard

Opportunity areas(vector)
river_basin_afforestation_with_EAD_grouped_gt0.gpkg

Opportunity areas are not further grouped – they are the collection of suitable areas for tree planting within each HydroBasins level 12 sub-basin (Lehner and Grill 2013). 

EAD aggregated to min/mean/max across model ensembles 

Filtered to exclude areas with a maximum EAD of less than 1 USD

Note that costs and carbon benefits are provided at 9 arc seconds (approximately 278m resolution at the equator) Assuming a mean 250x250m these numbers would need to be multiplied by 6.25 (250m x 250m / 10000m) for every grid square fully restored to estimate total costs and benefits.

Note that vector opportunity areas contain attributes for costs, carbon benefits, biodiversity benefits, and risks. Metadata CSV files provide additional notes on the data schema for each GeoPackage (.gpkg) and GeoParquet (.geoparquet) file.

Versions

1.0.0 - March 2025: Initial release

1.1.0 - July 2025: Correction to EAD calculation for landslides, affecting landslide/slope vegetation opportunity areas, revising the baseline damages down.

Acknowledgments

This dataset is an output of the project "Global Tools to Unlock Capital for Investments in Nature-Based Solutions" carried out by the Environmental Change Institute at the University of Oxford, in partnership with the Global Centre for Adaptation (GCA), supported by UK International Development with funds from the UK government.