Associated Press: Australian government leaders struck an agreement Thursday to conserve water on a crucial river system, but Prime Minister Kevin Rudd said the deal will not end the threat that a record drought poses to the waterway’s ecological health. Rudd and state leaders signed off on a 3.7 billion Australian dollar (US$3.6 billion) agreement that will reduce the amount of water wasted by farmers and towns who drain it from the drought-stricken Murray-Darling river system. Rudd’s plan is …