2Q about photosynthesis

[kimikoh]

1.what cause the rate of photosynthesis decrease?

2. In the first stage of photosynthesis [light reaction], hydrogen ions are pumped into?

[Draco]

I take it that you have already checked in your text book. Tell me if this site is useful to you.
http://en.wikipedia.org/wiki/Photosynthesis
Most people won't do homework questions unless you supply what you think the answer is first, then they will check your answer and help you correct any mistakes.