What is the German government doing to limit Turkish Immigration?

No law is directly implemented to turks. They have general laws that limit the immigration of foreigners but IMO its not helpful. Many cities are being "taken over" by them already.

3-hole fracked is right. Might I add, this sounds like you are proposing some mall cull or whatever. Before you start commenting on Turks in Germany, it might help if you knew more about the history of the Gastarbeiter (guest workers), and the ludicrous assumption that people would relocate and then politely go back again, despite having found permanent work. Until very recently, children of Turkish decent born in Germany were not automatically entitled to German passports. And if they were to switch, this would be expensive. I am happy to say this has since changed, although dual citizenship is still not permitted. In the US or UK, and I believe France too, we are much fairer, allowing dual citizenship and granting citizenship based on birthplace. Germany has a problem with Turkish integration. But Turks have a problem with German integration policies.

Well, the condition is pathetic. Its not the Turkish problem, the problem is they have not integrated in to the society. If you go to a place in Wedding in Berlin, you will feel that its turkey and not germany. This site has some information about the good and bad effects of Turkish population http://hubpages.com/hub/Accomodation-in-Berlin

First of all, the reason Turks came to Germany in the first place was because they were invited initially to work as cheap labor, much the same as Mexicans were in the southern and western United States. Once there, they began bringing over family members because the standard of living and generated incomes were higher. Now, the idea that 'auslanders' were taking jobs and intemingling has become a flashpoint for the political insiders who want to use race as a means of dividing and isolating the extremists so as to make it easier for them to get into office.