[R] several questions about R graphic properties

[Антон Морковин]

I have a several questions about R graphic properties. 
I use a "barplot2" function for creating plots with error bars. My data include species' names in first column, and I need make plots for each species. I know how to select species for each plot:

D<-read.table("FD_R.txt", h=T)
Dens<-D[D[,1]=="Sit.eur",]

but I want to make a cycle which will automatically change the species' name and save each plot in "jpg" file. How can I do it?

Also, my data include results of two-year work, and I want to make two plots for each year one above another in the same box. Is it possible?

And the last question: are there any functions in R which will allow to get data from Access? I know about "getfromaccess" function from vegan packcage, but it works only with environmental data with very restricted structure. 

I would be very much obliged for your answers.  

A. A. Morkovin, PhD student.

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