WoSIS latest - Effective cation exchange capacity - ISRIC

Capacity of the fine earth fraction* to hold exchangeable cations at the pH of the soil (ECEC). Conventionally approximated by summation of exchangeable bases (Ca2+, Mg2+, K+, and Na+) plus 1 N KCl exchangeable acidity (Al3+ and H+) in acidic soils (cmol(c)/kg).

ISRIC is developing a centralized and user–focused server database, known as ISRIC World Soil Information Service (WoSIS). The aims are to:

• Safeguard world soil data "as is"

• Share soil data (point, polygon, grid) upon their standardization and harmonization

• Provide quality-assessed input for a growing range of environmental applications.

So far some 450,000 profiles have been imported into WoSIS from disparate soil databases; some 196,000 of have been standardised. The number of measured data for each property varies between proﬁles and with depth, generally depending on the purpose of the initial studies. Further, in most source data sets, there are fewer data for soil physical as opposed to soil chemical attributes and there are fewer measurements for deeper than for superficial horizons. Generally, limited quality information is associated with the various source data.

Special attention has been paid to the standardization of soil analytical method descriptions with focus on the set of soil properties considered in the GlobalSoilMap specifications. Newly developed procedures for the above, that consider the soil property, analytical method and unit of measurement, have been applied to the present set of geo-referenced soil profile data.

Gradually, the quality assessed and harmonized "shared" data will be made available to the international community through several webservices. All data managed in WoSIS are handled in conformance with ISRICs data use and citation policy, respecting inherited restrictions.

The most recent set of standardized attributes derived from WoSIS are available via WFS. For instructions see Procedures manual 2018, Appendix A, link below (Procedures manual 2018).

* The fine earth fraction is generally defined as being less than 2 mm. However, an upper limit of 1 mm was used in the former Soviet Union and its sattelite states (Katchynsky scheme). This has been indicated in the database.

Citation proposal
. WoSIS latest - Effective cation exchange capacity - ISRIC. https://data.isric.org/geonetwork/srv/api/records/3ed0d2a2-8822-421b-8e89-a7f3bb8a973a