7Pankhurst C E,Stirling G R,Magarey R C,et al.Quantification of the effects of rotation breaks on soil biological properties and their impact on yield decline in sugarcane[ J ].Soil Biology and Biochemistry,2005,37:1121-1130.
8Michalk D L,Mueller H P.Strategies to improve cropland soils in North Korea using pasture leys[ J ].Agriculture,Ecosystems and Environment,2003,95:185-202.
9Helena B,Oborn I,Jonsson S,et al.Field balances of some mineral nutrients and trace elements in organic and conventional dairy farming/a case study at Ojebyn,Sweden[ J ].Europ J Agronomy,2003,20:101-116.
10Fernando G P,Oswaldo E,Guillermo S P,et al.Integrating no-till into crop-pasture rotations in Uruguay[ J ].Soil and Tillage Research,2004,77:1-13.