Ecological-economic optimization of land-use structure with the theory of Collected Information Complex Concert Control—A case study of Guyuan County of Ningxia Hui Autonomous Region

The theory and approachs of Collected Information Complex Concert Control (CICCC) are used to ecologically and economically optimize the land-use systems based on a case study of Guyuan County, Ningxia Hui Autonomous Region, a loess hill area. Gross grain output and sediment transport module are designed as the objective factors while land-use structure, precipitation and cumulative temperature as structural factors and ecological and economic data ranging from 1949 to 2003 are used. The result is that the grasslands are especially important to the gross grain output and the conservation of soil and water. The optimization of land-use system could help achieve both the growth of gross grain output and the decrease of sediment transport module. The analysis result of CICCC shows that the maximum gross grain output in Guyuan County is 18.92′104 t·a-1 , while the minimum sediment transport module is 1 052.9 t·km-2·a-1. And provided that the weight value of each objective factor is same, the optimized adjustment scheme of land-use is that all cultivated land on the slope with more than 25° gradient, and part cultivated slope land with 10° to 25° gradient are returned to the forestlands or grasslands, on the basis of land-use structure in 2003, which will reach 30 700 hm2. The sediment transport module will decrease from 6 000 t·km-2·a-1 to 2 000 t·km-2·a-1, and the ratio of grain self-supplying can sustains to 70% or so.