Holy Tree on QuShui, Tibet - Photo by Yongjiu Dai

The Global Soil Dataset for Earth System Modeling

Introduction | Data citation | Data download

Introduction

We developed a comprehensive, gridded Global Soil Dataset for use in Earth System Models (GSDE) and other applications as well. GSDE provides soil information including soil particle-size distribution, organic carbon, and nutrients, etc. and quality control information in terms of confidence level. GSDE is based on the Soil Map of the World and various regional and national soil databases, including soil attribute data and soil maps. We used a standardized data structure and data processing procedures to harmonize the data collected from various sources. We then used a soil type linkage method (i.e. taxotransfer rules) and the polygon linkage method to derive the spatial distribution of soil properties. To aggregate the attributes of different compositions of a mapping unit, we used three mapping approaches: area-weighting method, the dominant soil type method and the dominant binned soil attribute method. In the released gridded dataset, we used the area-weighting method as it will meet the demands of most applications. The dataset can be also aggregate to a lower resolution. The resolution is 30 arc-seconds (about 1 km at the equator). The vertical variation of soil property was captured by eight layers to the depth of 2.3 m (i.e. 0- 0.045, 0.045- 0.091, 0.091- 0.166, 0.166- 0.289, 0.289- 0.493, 0.493- 0.829, 0.829- 1.383 and 1.383- 2.296 m).

The documentation of the dataset can be downloaded here, including readme file and the data citation paper (with its auxiliary material).

Data citation

Shangguan, W., Dai, Y., Duan, Q., Liu, B. and Yuan, H., 2014. A Global Soil Data Set for Earth System Modeling. Journal of Advances in Modeling Earth Systems, 6: 249-263 .

Data download

The dataset in binary and NetCDF format can be downloaded in the following table.

There are for 11 types of soil general information for soil profiles and 34 soil properties for 8 depths. We provided two versions with different resolution, i.e., 30 seconds (~1km) and 5 minutes (~10km).

The soil general information of 30 seconds version is as follows:

No. Description Units Binary file NetCDF file

1

additional property

 

ADD_PROP

ADD_PROP

2

available water capacity

 

AWC_CLASS

AWC_CLASS

3

drainage class

 

DRAINAGE

DRAINAGE

4

impermeable layer

 

IL

IL

5

nonsoil class

 

NONSOIL

NONSOIL

6

phase1

 

PHASE1

PHASE1

7

phase2

 

PHASE2

PHASE2

8

reference soil depth

cm

REF_DEPTH

REF_DEPTH

9

obstacle to roots

 

ROOTS

ROOTS

10

soil water regime

 

SWR

SWR

11

topsoil texture

 

T_TEXTURE

T_TEXTURE


5 minutes version: general.zip

The 34 soil properties had 8 binary files for each of them. Each binary file contains the information of 1 layer. The name of each file end with a number to indicate the layer order from the top to the bottom. For NetCDF format, one file is for the top four layers, the other is for the bottom 4 layers. 30 seconds version is as follows:

No. Attrubute units Scale factor Binary file NetCDF file

1

total carbon

% of weight

0.01

TC

TC1,TC2

2

organic carbon

% of weight

0.01

OC

OC1,OC2

3

total N

% of weight

0.01

TN

TN1,TN2

4

total S

% of weight

0.01

TS

TS1,TS2

5

CaCO3

% of weight

0.01

CACO3

CACO31,CACO32

6

gypsum

% of weight

0.01

GYP

GYP1,GYP2

7

pH(H2O)

 

0.1

PHH2O

PHH2O1,PHH2O2

8

pH(KCl)

 

0.1

PHK

PHK1,PHK2

9

pH(CaCl2)

 

0.1

PHCA

PHCA1,PHCA2

10

Electrical conductivity

ds/m

0.01

ECE

ECE1,ECE2

11

Exchangeable calcium

cmol/kg

0.01

EXCA

EXCA1,EXCA2

12

Exchangeable magnesium

cmol/kg

0.01

EXMG

EXMG1,EXMG2

13

Exchangeable sodium

cmol/kg

0.01

EXNA

EXNA1,EXNA2

14

Exchangeable potassium

cmol/kg

0.01

EXK

EXK1,EXK2

15

Exchangeable aluminum

cmol/kg

0.01

EXAL

EXAL1,EXAL2

16

Exchangeable acidity

cmol/kg

0.01

EXH

EXH1,EXH2

17

Cation exchange capacity

cmol/kg

0.01

CEC

CEC1,CEC2

18

Base saturation

%

 

BS

BS1,BS2

19

Sand content

% of weight

 

SAND

SAND1,SAND2

20

Silt content

% of weight

 

SILT

SILT1,SILT2

21

Clay content

% of weight

 

CLAY

CLAY1,CLAY2

22

Gravel content

% of volume

 

GRAV

GRAV1,GRAV2

23

Bulk density

g/cm3

0.01

BD

BD1,BD2

24

Volumetric water content at -10 kPa

% of volume

 

VMC1

VMC11,VMC12

25

Volumetric water content at -33 kPa

% of volume

 

VMC2

VMC21,VMC22

26

Volumetric water content at -1500 kPa

% of volume

 

VMC3

VMC31,VMC32

27

The amount of phosphorous using the Bray1 method

ppm of weight

0.01

PBR

PBR1,PBR2

28

The amount of phosphorous by Olsen method

ppm of weight

0.01

POL

POL1,POL2

29

Phosphorous retention by New Zealand method

% of weight

0.01

PNZ

PNZ1,PNZ2

30

The amount of water soluble phosphorous

ppm of weight

0.0001

PHO

PHO1,PHO2

31

The amount of phosphorous by Mehlich method

ppm of weight

0.01

PMEH

PMEH1,PMEH2

32

exchangeable sodium percentage

% of weight

0.01

ESP

ESP1,ESP2

33

Total phosphorus

% of weight

0.0001

TP

TP1,TP2

34

Total potassium

% of weight

0.01

TK

TK1,TK2


5 minutes version is as follows (the names of the file indicate the No. in the above table): 1-9.zip, 10-18.zip, 19-26.zip, 27-34.zip
Soil organic carbon density: SOCD5min.zip