Abstract: Eight cropping systems including wheat rice,rice rice,rapeseed soybean,rapeseed peanut,wheat sesame,wheat cotton,pepper cabbage,radish eggplant were conducted to study manganese cycling and balance in farmland ecosystem of Jiang Han Plain in Hubei province The results show that the main output of manganese was crop harvest,which accounted for 81.3%-95.8% of total,while field runoff and soil leaching of manganese were very little The main inputs were from organic fertilizer,rainfall and natural return,while inputs from inorganic fertilizer and seeds (seedlings) were very little The results show that the manganese balance were more positive in two patterns of rice and commercial vegetable ecosystems,and negative in upland field ecosystem without organic fertilizer input

Key words: yield potential, North China Plain, variety adaptation, climate change, maize.