COPENHAGEN (Reuters) -Denmark's farmers on Wednesday voiced concerns that plans to levy a carbon emission tax on farming as part of efforts to meet Denmark's ambitious climate goals would force them to reduce production and close farms. Denmark, a major pork and dairy exporter, could become the first country in the world to levy an emissions tax on farming, a move that has broad political backing in the country, after New Zealand last year pushed back such a tax to the end of 2025. A carbon tax on farmers could help Denmark achieve its legally-binding 2030 target of cutting greenhouse gas emissions by 70% from 1990 levels.