Ammonia emission from agricultural sector have negative impact on human health and ecosystems. Excess ammonia deposition leads to acidification, eutrophication and climate change in China. This study aims to provide a high-resolution ammonia emission inventory in China and evaluate benefits of ammonia emission mitigation strategies. This will be done by: (i) improving the spatial variation in ammonia emission in China using empirical model approaches, (ii) improving temporal patterns of ammonia emissions, (iii) assessing the spatial variation in critical nitrogen loads for terrestrial ecosystems in China and (iv) assessing the impacts of ammonia abatement strategies on spatial patterns of ammonia emission deposition and impacts.