search

PNHP / COA

Pennnsylvania Conservation Opportunity Area Tool development scripts
GNU General Public License v3.0
2 stars 1 forks source link

Some aquatic SGCN is represented by flowlines and are not picked up by adjacent planning units that represent larger streams #77

Open ChristopherTracey opened 7 years ago

ChristopherTracey commented 7 years ago

The following PU overlaps the center of the river where the flowline that attributed the polygon is. map Within, we pick up the following three aquatic species: Brook Trout, Salamander Mussel, Mudpuppy

However, when we select the next planning unit to the southeast, even though a significant amount of it overlaps the river, we don't get the same result, in fact no aquatic species are picked up. map1

We should figure out an approach to tag the aquatic species to the the extent of the river as well as any overlapping PUs.

ChristopherTracey commented 6 years ago

Developed a potential fix for this. Methods are as follows:

  1. Get the "NHD Area" datasets merged and clipped for the state boundary.
  2. Intersect these with the NHD catchments to break the NHD area dataset into sections that contain each of the flowlines.
  3. Dissolve the newly intersected NHD area polygons by the COMID for the flowlines (be careful not to use the COMID for the NHDarea, which uses a different value!). This cleans up any fragments from the intersection.

The following two steps haven't been completed yet and I would love some feedback on at least the first one @memoore and @dyeany..

  1. Next we should intersect these with the hexagon layer to get a list of COMID by unique_IDs. However, should we not include an hexagons in the intersection that have less than a certain percentage of river area? If so, what should the percentage be?
  2. After this, we need to merge this back into the aquatic flowlines by PU dataset and remove any duplicates sourced from the original flowline by PU table.
ChristopherTracey commented 6 years ago

I left out a step where one of the of goals of this is to have the flowline length integrated into whatever overlapping PU is select. I don't have a good idea on how to do this-- ideas are welcome.