A trade-off analysis of policy objectives for Ansai, the Loess Plateau of China

Ansai is a county characterized by hilly loess relief that experiences all problems typical to the Loess Plateau of northern China, such as population pressure, soil loss, over-use of marginal lands, and poverty and food insecurity problems. Alleviation of these problems needs an integrated consideration of different objectives. To learn about the potentials and limitations of agricultural development and conflicts between objectives, this study conducted a systematic and trade-off analysis of different policy objectives, based on a land use optimization model (linear programming) integrating biophysical, agro-technical and socio-economic information. The results can serve two purposes, i.e., to reveal the solution space for each of the objectives and to analyze trade-off relationships between pairs of objectives. The information also forms the basis for further scenario analysis in which several objectives are considered simultaneously. The study results show that from an agro-technical point of view large opportunities exist to reduce the serious soil losses induced by crop cultivation on marginal lands, while still achieving food self-sufficiency. This can be achieved by reducing the area of marginal farmlands and efficient use of the most suitable land units, or/and by use of soil conservation measures (terracing and agro-techniques of furrow-ridging, residue mulching and rotational cropping with alfalfa). In general, achieving soil loss control was largely in agreement with improving production efficiency. However, the goal for maintenance of employment in agriculture strongly conflicted with environmental and productivity objectives. An increase of employment was associated with a distinct increase of (marginal) land area to be used for cropping, soil loss, total production cost and use of agro-chemicals, but with an almost linear decrease of labor productivity. The trade-off results also indicated that for a specific objective, a small deviation from its optimum value could result in a great improvement for most other objectives. These so-called nearly optimum solutions could be appealing alternatives to stakeholders. The study suggests that to promote a sustainable development in Ansai, policies are needed that stimulate efficient resource use and create opportunities for off-farm employment and income.