With international negotiations on the Kyoto climate change treaty set to continue this fall, the U.S. is proposing that countries get the same amount of credit for using forests and farmland to absorb carbon dioxide as they would for reducing CO2 emissions from power plants and cars. The State Department says the carbon-sink effect in the U.S. could cut by as much as 50 percent the amount of CO2 reductions the country would have to make to comply with Kyoto. U.S. officials acknowledged last night that adding farmers and foresters to the list of Kyoto allies could improve the treaty’s chances in the Senate. Canada, Russia, Japan, and Australia seem likely to back the U.S. approach. But the European Union will be firmly opposed to the position, and many environmental groups argue that at best carbon sinks provide only a temporary solution to the problems of CO2 emissions and that the U.S. proposal would create a major loophole in the treaty.