I think there is no special reason for these spikes. We saw strong short-selling early this week and its continuation in the first few minutes this morning. That's why I suppose some stop orders responsible for this little rally at 11 AM CET.
Let's look at the FDAX 09/03 Time&Sales:
10:59:00 last: 3347.0 total volume: 12924
11:00:33 last: 3351.5 total volume: 13403
11:00:35 last: 3359.0 total volume: 13702
You can see heavy activity at that time. This indicates some emergency trades. There was no decisive reason apart from the stop of the short term downtrend.