[R-sig-ME] mixed-effects model with crossed random effects

[Magdalena Wiedermann]

Dear list,

I am using the nlme package to analyze a mixed effects model. I am 
dealing with crossed random effects, meaning that I have repeated 
measures in time and space (on a split plot design). We are sampling 
water at two depth within one of each vegetation treatment (3 veg 
treatments) organized in 4 blocks.

I figured that the code including the spacial component only would be!?:
<-lme(responses~veg*depth*year*Month, random=~1|block/veg)

I am aware that 4 blocks is not pretty for it to be a random effect, but 
I am not interested in it as fixed effects. Also I am aware that there 
are very many philosophies and views on what a random effect is/should be.

Can anybody please help me with adding the temporal component in? 
Samples on these plots were taken 5 times each year for 3 years => 15 
times of repeated measures

I'd be more than happy about any suggestions, similar examples etc.
Thank you so much!
Lena

	[[alternative HTML version deleted]]