Check this:

http://nickbader.whitman.edu/research/protocols/litterbag

this:

http://www.sciencedirect.com/science/article/pii/S0038071705001495

and this:

http://onlinelibrary.wiley.com/doi/10.2307/1940104/full

To set up an experiment we need to know your research question. So what exactly are you going to measure and why?

Kind regards,

Michał Filipiak

Thank you very much! Actually I intend to measure the decomposition rate. Moreover, I also want to know which factors influence the decomposition of plant litter? I have reviewed some articles. It seems that most experiments were implemented in the field. I want to know if the decomposition experiment can be done in the laboratory. Thanks again!!!

Yes, such an experiment may be done in a laboratory. You may use plastic buckets filled with soil and litter on the top to simulate natural soil and litter. Bury a litterbag in the bucket just like you would do in a terrain study. 1 bucket = 1 sample. You may create various condition in buckets to test your predictions (humidity, temp., litter type, nitrogen, nutrients, stoichiometry, organisms and their diversity, etc.). It would be the best to store these buckets in a climatic chamber to control environmental factors. If not possible, you may create mesocosms. Along with litterbags you should bury some temperature and humidity recorders.

This book may help you to choose factors:

http://www.springer.com/br/book/9783642388200

Kind regards,

Michał Filipiak

Thanks very much for your sincere help!

You are welcome.