Found 3 schemes.
A semantic standard developed by the Food and Agriculture Organization (FAO) of the United Nations, AgMES enables description, resource discovery, interoperability and data exchange of different types of information resources in all areas relevant to food production, nutrition and rural development.
The standard is maintained by AIMS (Agricultural Information Management Standards), and while it has been used in various application profiles, it is now deprecated for new uses and will no longer be updated.
A metadata standard drawing on Dublin Core and AgMES created specifically to enhance the description, exchange and subsequent retrieval of agricultural Document-Like Information Objects.
An early metadata initiative from the Earth sciences community, intended for the description of scientific data sets. It includes elements focusing on instruments that capture data, temporal and spatial characteristics of the data, and projects with which the dataset is associated. It is defined as a W3C XML Schema.
Sponsored by the Global Change Master Directory, the DIF Writer's Guide Version 6 is from November 2010.