Displaying 20 results from an estimated 4000 matches similar to: "Vegan: Anova.CCA accessing original data using option by="margin""
2007 Apr 27
1
partitioning variation using the Vegan CCA routine?
Hello
I am using Jari Oksanen's CCA routine from the Vegan package on some estuary
data, following a technique applied in (Anderson, M.J. & Gribble, N.A.,
1998, Partitioning the variation among spatial, temporal and environmental
components in a multivariate data set, Australian Journal of Ecology 23,
158-167).
Some steps in the process require that the dependent matrix be constrained
by
2007 Jul 23
1
cca and cca.predict in vegan-what sort of prediction is possible
Hi All
I am not clear quite how one could use cca from package vegan and the associated
predict.cca to predict species abundance from environmental data (or if this is possible
in a generalised way). In other words, can one derive a cca object based on known
community data and use that to predict e.g. species abundances in a different number
of samples based on environmental data? The help
2009 Sep 04
1
NA in cca (vegan)
Dear all,
I would like to calculate a cca (package vegan) with species and environmental data. One of these environmental variables is cos(EXPOSURE).
The problem: for flat releves there is no exposure. The value is missing and I can't call it 0 as 0 stands for east and west.
The cca does not run with missing values. What can I do to make vegan cca ignoring these missing values?
Thanks a lot,
2010 Sep 21
1
partial dbRDA or CCA with two distance objects in Vegan.
I am trying to use the cca/rda/capscale functions in vegan to analyse
genetic distance data ( provided as a dist object calculated using
dist.genpop in package adegenet) with geographic distance partialled out
( provided as a distance object using dist function in veganthis method
is attempting to follow the method used by Geffen et al 2004 as
suggested by Legendre and . FORTIN (2010).
I
2011 Mar 10
1
vegan CCA I am Completely new to ordination analyses
Dear list,
I am trying to predict species volume from bioclimatic data, I have various
sites and I have a data frame with species volume and
the corresponding bioclimatic data for each site.
I read on a discussion forum that you can use ordination to predict species
abundance (in my case volume) from 'new' climate data for sites where you do
not know the abundance.
Unfortunately I
2010 Aug 14
1
cca biplot (vegan) failed in matplot
Dear List,
I am trying to plot the result of cca using matplot but failed.
Pls kindly help and thanks.
Elaine
The error message was
error in xy.coords(x, y, xlabel, ylabel, log = log) :
(list) object cannot be coerced to type 'double'
code
rm(list=ls())
library(vegan)
library(MASS)
# input richness
birdrich
2010 Jul 17
2
cca in vegan (formula instead of community matrix data)
Dear List,
I tried to do cca based on species data and environmental variables (formula
instead of community data).
However, there was an error saying row sums must be >0.
I searched the previous related messages but found few solutions.
Please kindly help and thank you in advance.
code
This is vegan 1.17-3
Warning message:
package 'vegan' was built under R version 2.10.1
2012 Nov 09
1
CCA with Vegan - Plot problem
Hi,
I've just started using R and am having some problems with CCA using vegan.
I'm looking at abundance p/m2 (hence decimals) vs environmental variables
and have been using
http://ecology.msu.montana.edu/labdsv/R/labs/lab12/lab12.html to guide me
through.
My organism data looks like this:
Sample "Species_1" "Species_2" "Species_3" etc
Sample_1
2009 Sep 09
2
"predict"-fuction for metaMDS (vegan)
Dear r-Community,
Step1: I would like to calculate a NMDS (package vegan, function metaMDS) with species data.
Step2: Then I want to plot environmental variables over it, using function envfit.
The Problem: One of these environmental variables is cos(EXPOSURE). But for flat releves there is no exposure. The value is missing and I can't call it 0 as 0 stands for east and west. Therefore I
2014 Sep 13
1
vegan moved to GitHub and vegan 2.2-0 is coming (are you ready?)
Dear vegan team,
Vegan development happens now completely in github. R-Forge repository is no more in sync with github. I tried to commit all github changes to R-Forge, but a week ago I got a conflict in file and I haven't had time to resolve that conflict. You can follow vegan development and vegan discussion also without signing to github. The system seems to be completely open and does not
2013 Mar 27
1
Conditional CCA and Monte Carlo - Help!
Hi All,
I am using canonical correspondence analysis to compare a community
composition matrix to a matrix of sample spatial relationships and
environmental variables. In order to parse out how much variance is
explained purely by space (S/E) or the environment (E/S) I am using a
conditional (partial) CCA. I want to test significance via Monte Carlo but
I can not find a way to do this with a
2004 Jan 14
1
cca in vegan
Hello all,
I'm hoping this is a simple problem.
I'm trying to do cca of my data. I have my plant data and environmental data as 2 separate files. I have 3 years of data, stacked vertically, within these files. I want to conduct the cca for each year and am trying to create separate year files using the following:
cnts94 <- cnts[1:27,]
env94 <- env[1:27,]
when I run
2010 Apr 27
1
cca standard error species
Dear all,
I realised a correspondence analysis with function cca() of vegan library.
Just like in Okansen (2010) in the example of R help:
library(vegan)
data(varespec)
data(varechem)
vare.cca<-cca(varespec~ Al + P + K, varechem)
With plot.cca() function I represented the species matrix in the next way:
plot(vare.cca,display="species")
Being similar to:
plot((c(-2,2)),(c(-2,2)),
2011 Nov 07
2
ordination in vegan: what does downweight() do?
Can anyone point me in the right direction of figuring out what downweight()
is doing?
I am using vegan to perform CCA on diatom assemblage data. I have a lot of
rare species, so I want to reduce the influence of rare species in my CCA. I
have read that some authors reduce rare species by only including species
with an abundance of at least 1% in at least one sample (other authors use
5% as a
2009 Mar 20
1
CCA - manual selection
Hello,
I am trying to obtain f-values for response (independent) variables from a
CCA performed in vegan package, to see which ones of them have
significative influence in my dependent variables (like the manual selection
in canoco), but I can't find any function (or package) that do such a thing.
The dependents variables are species data, and the independents are
ambiental data.
Than you.
2008 Sep 26
1
cca constraining variables table
I performed canonical correspondence analysis (cca) with the example data of
vegan, but I'm not able to obtain a table like scores() for the constraining
variables. I can see them in the summary() mode, but it would be great to
have in a separate table. Any suggestion?, thanx Gianandrea
require(vegan)
data(varespec)
data(varechem)
vare.cca<-cca(varespec,varechem)
scores(vare.cca)
2009 Feb 08
0
library vegan - cca - versus CANOCO
Hi R users,
I have two data matrix, one with community data and another with
environmental data. Prior to preform the CCA, I have used PCA to select some
environmental variables and to avoid redundance information. The result is
that I have 4 environmental variables and my community data matrix where,
following bibliography, I have eliminated rare species.
All variables were log-transformed (x+1)
2011 Sep 26
0
vegan cca: syntax
Dear all,
I am a new member to the list - and to the analysis that I am attempting.
I have the following case
A group of us have been monitoring (over a period of a few years) a number
of paired plots that were flooded and / or burnt.
The plots are located in two topographical settings, some were burnt, some
were flooded, some were burnt & flooded and some were not affected at all.
At
2012 Nov 27
1
CCA plot
Hi, I have a couple questions about fitting environmental (land use
factors, plant species presence-absence, and soil variables) constraints to
my CCA biplot. 1. After successfully plotting species and site scores in my
CCA, I have been trying to insert the biplot arrows of the environmental
constraints in my data set using the text() function. When I do that, the
plot changes completely. Is there
2023 Dec 08
2
regarding CCA plot
Hii rstudio members
I am learning rstudio, For my manuscript I am trying to plot CCA using
species and environmental data. But I am getting error like
Error in cca.default(sptrans, envtrans) :
all row sums must be >0 in the community data matrix
*My code is like *
library(vegan)
library(ggplot2)
library(dplyr)
rassspec<-read.csv("C:/Users/hp/Desktop/R_data/rassspec.csv",