Improving the productivity and sustainability of rainfed farming systems for the Loess Plateau of Gansu Province

![CDATA[The climate, soils and farming systems from Dingxi and Xifeng, two regional centers of eastern Gansu Province are described. Farm size is small (1 ha) and farm income is low ($A330 per person and year). Farmers grow a mixture of crops and livestock for subsistence and cash income. A feature of the environment is highly variable rainfall and an agricultural system that relies on stored soil water from the summer rain season (July to September) for use by crops and forages in the following spring. Research evaluating conservation tillage under local conditions has produced encouraging results with grain yields from an experimental no-tillage stubble retained treatment equal to or greater than grain yields from a conventional tillage and stubble removed treatment across a range of crops and seasons. This research will move from a “proof of concept” phase to an “on-farm research” phase where the focus will be on how farmers adapt conservation tillage to local conditions. The implications of integrating lucerne (Medicago sativa) into cereal cropping systems for soil water dynamics, soil nitrogen, and productivity of lucerne and wheat were also studied. Lucerne is highly productive in this environment and can minimize water “losses” through runoff and drainage. Productive lucerne / wheat rotations can be developed but the transition from the perennial forage to the annual crop needs to be managed carefully to avoid risks associated with dry soil and/or low soil inorganic nitrogen. The combination of field experimentation to create comprehensive databases, with simulation modeling, and on-farm research, has significantly contributed to a better understanding of the constraints and opportunities in these farming systems. Future research will focus on farmer adaptation of conservation tillage and integration of forages and crop residues for livestock production.]]