التعريف: Organic matter in soil which has reached a point of stability, where it will break down no further and might, if conditions do not change, remain essentially as it is for centuries, or millennia.
التعريف: A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)
التعريف: The institution that holds a type specimen for a given species. The recommended best practice is to use the identifier in a collections registry such as the Biodiversity Collections Index (http://www.biodiversitycollectionsindex.org/).
