The feature of the nutrient cycle and balance of the six primary strip lands were studied by investigating the input and output nutrients of the six patterns in Xingdian irrigation district.The results indicated that N

P and K cycle of the five planting patterns were good with the exception of nitrogen deficiency of wheat/soybean strip field

but the only balance condition was adequate manure input and symbiotic nitrogen-fixing of legume crops.Manure provided 4.62%~8.93% N

17.34%~22.31% P and 72.61%~82.07% K of total nutrients.Legume crops provided 14.08%~42.45% N of total nitrogen.The amount of N and P coming from fertilizers occupied 52.27%~76.06% and 61.40%~70.91% of total N and P

respectively.There were 8.35%~12.04% N

3.72%~7.74% P and 9.20%~17.48% K of total nutrients input to the strip lands ecosystem by rainfall and irrigation.The proportion of N

P

K input

observing from the structure of fertilization

were extremely unreasonable in all the six planting patterns.The countermeasure should be carried out to control the application amount of N and to increase the application rate of K.Meanwhile

the application of fertilizer K should be focused on.The technique to return crop straw into farmland and harvest in high stubble should be extended to increase the nutrient recycle and reuse efficiency.