randomized block design analysis in R

---------- Forwarded message ----------
From: alis villiyam <aalisiyan at gmail.com>
Date: Mon, Jul 27, 2009 at 9:47 AM
Subject: randomized block design analysis in R
To: bolker at zoology.ufl.edu


Dear Tae-kyun Kim

Hello,

I'm a  student and I have some trouble with the experimental
(columns-experiments) design of my project. I use a randomized block design
with 4 treatments including a control. For each treatment, I use 3
replicates and 3 blocks.

The treatments are:

-T1 = COD (300 mg/Lit)   COD=chemical oxygen demand

-T2 = COD (200 mg/Lit)

-T3 = COD (100 mg/Lit)

-T4 = COD (0 mg/Lit) as a control

The experiment is conducted during three months and a sample is taken each
Week in every experimental unit.

At the first, I irrigated all soil columns (12 columns) with demonize water
for 1 week.

Then during 8 weeks, I irrigated all columns with waste water with different
concentration. Then, gain, I irrigated all columns with demonize water for 4
weeks.

Now I want to know how I can analyses the results in R. For example, I want
to detect the
Effect of waste water on some physical properties of soil, before, during
use waste water and after use waste water (Is there any significant change
in properties of soil.) Time is also important, so I want to know the
interaction between time and some physical properties of soil, like water
content .first comprises between Treatments and then comprise between
weeks).

Questions to be answered:

1)      Theta (water content), before (1 week) and after the COD; is there a
difference?
2)      Theta, during, before and after the COD; is there a difference?
3)      Is there a trend in Theta, during COD (8 weeks)?
4)      Is there a difference in Theta, during COD between the treatments?
I hope somebody can help me to find correct statistical analyses in R.


Kind regards,

Alisia