iSDA Soil#

Products used: iSDA Soil; iSDA Soil Bedrock Depth; iSDA Soil Bulk Density; iSDA Soil Carbon Total; iSDA Soil Clay Content; iSDA Soil Sand Content; iSDA Soil Silt Content;

Date modified: 31 October 2023

Background#

Innovative Solutions for Decision Agriculture iSDA soil is an open access soils data resource for the African continent. The key data products are spatial predictions of soil nutrient concentrations and soil properties, derived from predictive soil mapping (PSM) techniques.

Soils data can be useful for a range of applications including land suitability mapping for agriculture, soil amelioration planning (e.g. liming to address acidic soils or fertiliser to address fertility constraints), and for construction or infrastructure planning.

iSDA variables#

iSDA offers numerous soil variables shown in the table below. Many of the variables have four layers: mean and standard deviation at 0-20cm and 20-50cm depth. Layers are accessible via their Access Names e.g. ‘bedrock_depth’ in the Sandbox.

Some variables are indexed in Digital Earth Africa, and others can be brought in directly.

Table 1: iSDA soil products available on the DE Africa platform.

Variable	Access Name	Layers
Depth to bedrock	bedrock_depth	0-200cm depth, predicted mean and standard deviation
Bulk density, <2mm fraction	bulk_density	0-20cm and 20-50cm, predicted mean and standard deviation
Carbon, total	carbon_total	0-20cm and 20-50cm, predicted mean and standard deviation
Clay content	clay_content	0-20 cm and 20-50 cm, predicted mean and standard deviation
Sand content	sand_content	0-20cm and 20-50cm, predicted mean and standard deviation
Silt content	silt_content	0-20cm and 20-50cm, predicted mean and standard deviation

Relevant metadata for the iSDA soil products, as well as the specific temporal and geographic extents for the product can be explored as an interactive map on the DE Africa Metadata Explorer. Data is available for the shaded region. A Jupyter Notebook which demonstrates loading and using iSDA soil products in the Sandbox is also available.

Figure 1: iSDA soil bedrock depth geographic extent

iSDA Soil Geographic Extent

Technical information#

Spatial prediction of soil properties in the iSDA product suite was undertaken with five regression modelling algorithms. The prediction process utilises field data in combination with covariates such as topographic and surface reflectance data. Further technical information on iSDA products, and links to academic papers describing the methodology, can be found on the iSDA technical information page.

References#

Miller MAE, Shepherd KD, Kisitu B, Collinson J (2021) iSDAsoil: The first continent-scale soil property map at 30 m resolution provides a soil information revolution for Africa. PLoS Biol 19(11): e3001441. https://doi.org/10.1371/journal.pbio.3001441

License and Acknowledgements#

This data is licensed under a Creative Commons by Attribution (CC BY 4.0) license.

Credits: iSDA

Product Details#

The specifications for the six products listed above in Table 1 are described in succession below.

1. iSDA Soil Bedrock Depth#

Product Overview#

Soil bedrock depth can be useful for development planning, such as agricultural developments or construction.

Specifications#

Table 2: iSDA soil bedrock depth product specifications

Specification
Product name	`isda_soil_bedrock_depth`
Cell size - X (metres)	30
Cell size - Y (metres)	30
Coordinate reference system	EPSG:3857
Update frequency	None

Measurements#

Table 3: iSDA soil bedrock depth product measurements

Band ID	Description	Units	Data type	No data\(^\dagger\)
mean_0_200	Soil bedrock depth, mean prediction 0-200cm	cm	float32	NaN
stdev_0_200	Soil bedrock depth, prediction standard deviation 0-200cm	cm	float32	NaN

Media and example images#

Figure 2: iSDA soil bedrock depth (cm) for an area near Cape Town, South Africa.

iSDA Bedrock Depth

Data Access#

Amazon web services S3#

iSDA layers are available in AWS S3, details below. iSDA has published documentation on accessing data through AWS.

Table 4: iSDA depth to bedrock access details through AWS.

AWS S3 details
Product	bedrock_depth
Bucket ARD	`arn:aws:s3:::isdasoil`
Region	`us-west-2`

Open Data Cube (ODC)#

The iSDA soil depth to bedrock product can be accessed through the Digital Earth Africa ODC API, which is available through the Digital Earth Africa Sandbox.

ODC product name: isda_soil_bedrock_depth

The isda_soil_bedrock_depth has two layers: the estimate itself and standard deviation as a measure of prediction uncertainty. They can be called by using the default name or by the band’s alternative name as listed in the table below.

Table 5: iSDA depth to bedrock band names.

Band name	Alternative names	Fill value
mean_0_200	MEAN_0_200	NaN
stdev_0_200	STDEV_0_200	NaN

2. iSDA Soil Bulk Density#

Product Overview#

Soil bulk density is a useful variable for understanding soil’s capacity to support ecosystem functions and other uses. It is also a useful input for planning soil additive rates.

Specifications#

Table 6: iSDA soil bulk density product specifications

Specification
Product name	`isda_soil_bulk_density`
Cell size - X (metres)	30
Cell size - Y (metres)	30
Coordinate reference system	EPSG:3857
Update frequency	None

Measurements#

Table 7: iSDA soil bulk density product measurements

Band ID	Description	Units	Data type	No data\(^\dagger\)
mean_0_20	Soil bulk density, mean prediction 0-20cm	g/cm\(^3\)	float32	NaN
mean_20_50	Soil bulk density, mean prediction 20-50cm	g/cm\(^3\)	float32	NaN
stdev_0_20	Soil bulk density, prediction standard deviation 0-20cm	g/cm\(^3\)	float32	NaN
stdev_20_50	Soil bulk density, prediction standard deviation 20-50cm	g/cm\(^3\)	float32	NaN

Media and example images#

Figure 3: iSDA soil bulk density (g/cm3) for an area near Cape Town, South Africa.

iSDA Bulk Density

Data Access#

Amazon web services S3#

iSDA layers are available in AWS S3, details below. iSDA has published documentation on accessing data through AWS.

Table 8: iSDA soil bulk density access details through AWS.

AWS S3 details
Product	bulk_density
Bucket ARD	`arn:aws:s3:::isdasoil`
Region	`us-west-2`

Open Data Cube (ODC)#

The iSDA soil bulk density product can be accessed through the Digital Earth Africa ODC API, which is available through the Digital Earth Africa Sandbox.

ODC product name: isda_soil_bulk_density

The isda_soil_bulk_density has two layers: the estimate itself and standard deviation as a measure of prediction uncertainty. They can be called by using the default name or by the band’s alternative name as listed in the table below.

Table 9: iSDA soil bulk density band names.

Band name	Alternative names	Fill value
mean_0_20	MEAN_0_20	NaN
mean_20_50	MEAN_20_50	NaN
stdev_0_20	STDEV_0_20	NaN
stdev_20_50	STDEV_20_50	NaN

3. iSDA Soil Carbon Total#

Product Overview#

Total soil carbon is critical to a range of application such as Carbon cycle and Land Degradation Neutrality (LDN) monitoring.

Specifications#

Table 10: iSDA soil carbon total product specifications

Specification
Product name	`isda_soil_carbon_total`
Cell size - X (metres)	30
Cell size - Y (metres)	30
Coordinate reference system	EPSG:3857
Update frequency	None

Measurements#

Table 11: iSDA soil carbon total product measurements

Band ID	Description	Units	Data type	No data\(^\dagger\)
mean_0_20	Soil carbon total, mean prediction 0-20cm	g/kg	float32	NaN
mean_20_50	Soil carbon total, mean prediction 20-50cm	g/kg	float32	NaN
stdev_0_20	Soil carbon total, prediction standard deviation 0-20cm	g/kg	float32	NaN
stdev_20_50	Soil carbon total, prediction standard deviation 20-50cm	g/kg	float32	NaN

Back Transformation#

Soil carbon total values must be transformed, in Python the transformation can be written as np.expm1(x/10).

Media and example images#

Figure 4: iSDA soil carbon total (g/kg) for an area near Lake Tana, Ethiopia.

iSDA Soil Carbon Total

Data Access#

Amazon web services S3#

iSDA layers are available in AWS S3, details below. iSDA has published documentation on accessing data through AWS.

Table 12: iSDA soil carbon total access details through AWS.

AWS S3 details
Product	carbon_total
Bucket ARD	`arn:aws:s3:::isdasoil`
Region	`us-west-2`

Open Data Cube (ODC)#

The iSDA soil carbon total product can be accessed through the Digital Earth Africa ODC API, which is available through the Digital Earth Africa Sandbox.

ODC product name: isda_soil_carbon_total

The isda_soil_carbon_total has two layers: the estimate itself and standard deviation as a measure of prediction uncertainty. They can be called by using the default name or by the band’s alternative name as listed in the table below.

Table 13: iSDA soil carbon total band names.

Band name	Alternative names	Fill value
mean_0_20	MEAN_0_20	NaN
mean_20_50	MEAN_20_50	NaN
stdev_0_20	STDEV_0_20	NaN
stdev_20_50	STDEV_20_50	NaN

4. iSDA Soil Clay Content#

Product Overview#

Soil clay content is one of three (sand, silt, clay) soil texture layers. Soil texture determines many other soil attributes, such as water and nutrient holding capacity.

Specifications#

Table 14: iSDA soil clay content product specifications

Specification
Product name	`isda_soil_clay_content`
Cell size - X (metres)	30
Cell size - Y (metres)	30
Coordinate reference system	EPSG:3857
Update frequency	None

Measurements#

Table 15: iSDA soil clay content total product measurements

Band ID	Description	Units	Data type	No data\(^\dagger\)
mean_0_20	Soil clay content, mean prediction 0-20cm	percent	float32	NaN
mean_20_50	Soil clay content, mean prediction 20-50cm	percent	float32	NaN
stdev_0_20	Soil clay content, prediction standard deviation 0-20cm	percent	float32	NaN
stdev_20_50	Soil clay content, prediction standard deviation 20-50cm	percent	float32	NaN

Media and example images#

Figure 5: iSDA soil clay content (%) in the Okavango Delta, Botswana.

iSDA Soil Clay Content

Credits: iSDA

Data Access#

Amazon web services S3#

iSDA layers are available in AWS S3, details below. iSDA has published documentation on accessing data through AWS.

Table 16: iSDA soil clay content access details through AWS.

AWS S3 details
Product	clay_content
Bucket ARD	`arn:aws:s3:::isdasoil`
Region	`us-west-2`

Open Data Cube (ODC)#

The iSDA soil clay content product can be accessed through the Digital Earth Africa ODC API, which is available through the Digital Earth Africa Sandbox.

ODC product name: isda_soil_clay_content

The isda_soil_clay_content has two layers: the estimate itself and standard deviation as a measure of prediction uncertainty. They can be called by using the default name or by the band’s alternative name as listed in the table below.

Table 17: iSDA soil clay content band names.

Band name	Alternative names	Fill value
mean_0_20	MEAN_0_20	NaN
mean_20_50	MEAN_20_50	NaN
stdev_0_20	STDEV_0_20	NaN
stdev_20_50	STDEV_20_50	NaN

5. iSDA Soil Sand Content#

Product Overview#

Innovative Solutions for Decision Agriculture iSDA soil is an open access soils data resource for the African continent. The key data products are spatial predictions of soil nutrient concentrations and soil properties, derived from predictive soil mapping (PSM) techniques.

Soil sand content is one of three (sand, silt, clay) soil texture layers. Soil texture determines many other soil attributes, such as water and nutrient holding capacity.

Specifications#

Table 18: iSDA soil sand content product specifications

Specification
Product name	`isda_soil_sand_content`
Cell size - X (metres)	30
Cell size - Y (metres)	30
Coordinate reference system	EPSG:3857
Update frequency	None

Measurements#

Table 19: iSDA soil sand content total product measurements

Band ID	Description	Units	Data type	No data\(^\dagger\)
mean_0_20	Soil sand content, mean prediction 0-20cm	percent	float32	NaN
mean_20_50	Soil sand content, mean prediction 20-50cm	percent	float32	NaN
stdev_0_20	Soil sand content, prediction standard deviation 0-20cm	percent	float32	NaN
stdev_20_50	Soil sand content, prediction standard deviation 20-50cm	percent	float32	NaN

Media and example images#

Figure 6: iSDA soil sand content (%) in the Okavango Delta, Botswana.

iSDA Soil Sand Content

Data Access#

Amazon web services S3#

iSDA layers are available in AWS S3, details below. iSDA has published documentation on accessing data through AWS.

Table 20: iSDA soil sand content access details through AWS.

AWS S3 details
Product	sand_content
Bucket ARD	`arn:aws:s3:::isdasoil`
Region	`us-west-2`

Open Data Cube (ODC)#

The iSDA soil sand content product can be accessed through the Digital Earth Africa ODC API, which is available through the Digital Earth Africa Sandbox.

ODC product name: isda_soil_sand_content

The isda_soil_sand_content has two layers: the estimate itself and standard deviation as a measure of prediction uncertainty. They can be called by using the default name or by the band’s alternative name as listed in the table below.

Table 21: iSDA soil sand content band names.

Band name	Alternative names	Fill value
mean_0_20	MEAN_0_20	NaN
mean_20_50	MEAN_20_50	NaN
stdev_0_20	STDEV_0_20	NaN
stdev_20_50	STDEV_20_50	NaN

6. iSDA Soil Silt Content#

Product Overview#

Soil silt content is one of three (sand, silt, clay) soil texture layers. Soil texture determines many other soil attributes, such as water and nutrient holding capacity.

Specifications#

Table 22: iSDA soil silt content product specifications

Specification
Product name	`isda_soil_silt_content`
Cell size - X (metres)	30
Cell size - Y (metres)	30
Coordinate reference system	EPSG:3857
Update frequency	None

Measurements#

Table 23: iSDA soil silt content total product measurements

Band ID	Description	Units	Data type	No data\(^\dagger\)
mean_0_20	Soil silt content, mean prediction 0-20cm	percent	float32	NaN
mean_20_50	Soil silt content, mean prediction 20-50cm	percent	float32	NaN
stdev_0_20	Soil silt content, prediction standard deviation 0-20cm	percent	float32	NaN
stdev_20_50	Soil silt content, prediction standard deviation 20-50cm	percent	float32	NaN

Media and example images#

Figure 7: iSDA soil silt content (%) in the Okavango Delta, Botswana.

iSDA Soil Silt Content

Data Access#

Amazon web services S3#

iSDA layers are available in AWS S3, details below. iSDA has published documentation on accessing data through AWS.

Table 24: iSDA soil silt content access details through AWS.

AWS S3 details
Product	silt_content
Bucket ARD	`arn:aws:s3:::isdasoil`
Region	`us-west-2`

Open Data Cube (ODC)#

The iSDA soil silt content product can be accessed through the Digital Earth Africa ODC API, which is available through the Digital Earth Africa Sandbox.

ODC product name: isda_soil_silt_content

The isda_soil_silt_content has two layers: the estimate itself and standard deviation as a measure of prediction uncertainty. They can be called by using the default name or by the band’s alternative name as listed in the table below.

Table 4: iSDA soil silt content band names.

Band name	Alternative names	Fill value
mean_0_20	MEAN_0_20	NaN
mean_20_50	MEAN_20_50	NaN
stdev_0_20	STDEV_0_20	NaN
stdev_20_50	STDEV_20_50	NaN