search for: edaphic

Displaying 3 results from an estimated 3 matches for "edaphic".

2010 Jun 09
1
ordisurf (pkg vegan) gives implausible result
I'm having trouble with the ordisurf function in the vegan package. I have created an ordination plot (cmdscale) of 60 samples based on Bray-Curtis dissimilarities, and would like to overlay various soil edaphic characteristics as possible clues to the clustering I observe in my plot. However, I find that ordisurf creates a surface on the plot that is a perfect, even gradient - and doesn't match my data. An example of this output is attached (as .ps file), while these are the data for the environmental...
2012 May 09
1
reception of (Vegan) envfit analysis by manuscript reviewers
...d with the envfit function in the Vegan package. Has anyone else struggled to effectively explain this analysis? If so, can you share any helpful tips? The most recent comment I've gotten back: "What this shows is which NMDS axis separates the communities, not the relationship between the edaphic factor and the Bray-Curtis distance." Thanks for any suggestions! Matt
2005 Aug 18
1
How to put factor variables in an nls formula ?
Hello, I want to fit a Gompertz model for tree diameter growth that depends on a 4 levels edaphic factor (?Drain?) and I don?t manage to introduce the factor variable in the formula. Dinc is the annual diameter increment and D is the Diameter. >treestab > Dinc D Drain [1,] 0.03 26.10 2 [2,] 0.04 13.05 1 [3,] 0.00 24.83 1 [4,] 0.00 15.92 4...