[R-sig-Geo] kriging as fish swim, not as crows fly

[Martin Renner]

Hi All,

I want to kirg fish and seabird densities within an estuary which has several arms. Since neither organisms cross land, the appropriate distances would not be euclidian but over-water (as fish swim). There are several papers, describing this problem and how to deal with it (see below), but I have not found an easily accessible implementation. Is anybody aware of a solution in R?

Best,
Martin



@article{Rathbun:1998aa,
	Author = {Rathbun, Stephen L.},
	Journal = {Environmetrics},
	Number = {2},
	Pages = {109--129},
	Title = {Spatial modelling in irregularly shaped regions: kriging estuaries},
	Volume = {9},
	Year = {1998}}

@article{Little:1997aa,
	Author = {Little, Laurie S. and Edwards, Don and Porter, Dwayne E.},
	Journal = {Journal of Experimental Marine Biology and Ecology},
	Number = {1},
	Pages = {1--11},
	Title = {Kriging in estuaries: as the crow flies, or as the fish swims?},
	Volume = {213},
	Year = {1997}}




Martin Renner				
US Geological Survey			
Alaska Science Center