On 15/2/23 02:00, Greg Troxel wrote:
For wetlands, the definitions in the US:
https://www.fws.gov/media/classification-wetlands-and-deepwater-habitats-united-states
Which is:
In general terms, wetlands are lands where saturation with water is the
dominant factor determining the nature of substrate development and the
types of plant and animal communities living in the substrate and on its
surface. The single feature that most wetlands share is a substrate that
is at least periodically saturated with or covered by water. The water
creates severe physiological problems for all plants and animals except
those that are specially adapted for such conditions.
The same definition is used in AU:
https://wetlandinfo.des.qld.gov.au/resources/static/pdf/ecology/soils/qw-soil-indicators.pdf
More or less, a wetland is characterized by being wet for at least a
portion of the growing season in a normal year. And, just because you
don't see standing water doesn't mean the soil is not wet.
I assume you are referring to this:
If neither plants nor soil is present, then the wetland identification
must be made strictly on the basis of hydrology. In this case, the
substrate should be “saturated with water or covered by shallow water at
some time during the growing season of each year.” Cowardin et al.
(1979) fully realized how vague this hydrologic definition was but,
given the lack of detailed hydrologic data from the diversity of wetland
types, geologic regions, and climatic regions of the U.S., there was no
way they could have been more specific.
This is a rule of thumb that is used if the plant and soil
characteristics are not present (or if the information is not
available). It is a rule based on wetland data from the US. The
Australian ecosystem is far more fragile and inundation less often than
annually is enough to make it the dominant factor.
_______________________________________________
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging
