The evaluation of ecoagricultural patterns of hill and downland in red soil areas

Based on the agricultural ecosystem, a gray system, application of the theory of gray system, and combination with main component analysis method, the 8 patterns of agricultural ecosystems were studied. They were grain food planting(FP), agro-pastoral(AP), agro-pastoral-forest(APF), agro-fruit-pastoral(AFP), agro-fruit(AF),agro-pastoral-agro-product processing(APAP), agro-pastoral-vegetable(APV), agro-pastoral-medical material(APMM), respectively. The results showed that the evaluation of eight eco-agricultural patterns was from 0.2013 to 0.5963.However, the evaluation of FP was the minimum, and it was 0.2013. The evaluation of FP was the maximum, and it was 0.5963.According to the theory of eco-agriculture developing, eco-agriculture was classified into four stages. They were single planting stage, primary stage, medium stage and super stage. Because the FP had minimum evaluation and it belongs to the single planting stage. The evaluation of APMM, AP,AF,APV,AS was between 0.3 and 0.5, therefore, they belong to the primary stage. As to the APAP and AFP, their evaluation were 0.5963 and 0.5134, they belong to the medium stage.