Romania on Thursday began shutting down its only remaining operating nuclear reactor as record-low water levels on the Danube have forced nuclear power shutdowns in central and eastern Europe in recent weeks. Nuclearelectrica has launched the process to disconnect the one operating reactor at Romania’s only nuclear plant at Cernavoda on the Danube, the Romanian state-owned nuclear power plant operator said on Thursday. Nuclearelectrica had shut down another reactor at Cernavoda at the end of July as scorching temperatures and drought in Europe…