| With the rapid growth of social economic and the acceleration of the urbanization and industrialization process, our country is facing a very serious environment problem, and soil erosion is a typical one in China recently. Research indicates that China is one of country which suffer the most intense social erosion, and soil erosion always results in many negative phenomenon, such as land deterioration, regional imbalance of ecology system and so on, all of which will restrict the development of agriculture and therefore threaten the survive of human being. The red soil region in southern China is a special district, whose geological landform and climate are both unique; in this area, frequent human activities pressure the ecosystem carrying capacity a lot, making the area the second place of disaster region suffering soil erosion most in the country. Despite the positive contribution of various protecting processes, such as artificial protection forests and the policies for returning farmland to forests, soil erosion caused by blind reclamation of the slope land in the hill is very serious and the water-soil conservation is still facing big challenge as the rapid urbanization is taking place here.Therefore, it is meaningful to do research on the soil erosion controlling techniques in order to reduce the ecological deterioration and enhance the sustainable development of economy meanwhile. In this research, run-off plots and rear-earth elements tracing method were employed. To test the effect of different contour hedgerow planting patterns in controlling the soil erosion on slopes, five contour hedgerow planting patterns, including single-row Ophiopogon japonicas(M), single-row Hemerocallis citrine(H), double-row Ophiopogon japonicas(MM), double-row Hemerocallis citrine(HH), and double-row Ophiopogon japonicas and Hemerocallis citrine(MH), were settled in the experimental area in Yongning, Zhuji, Zhejiang Province, while the bare slope was taken as the blank control. There are 40 run-off plots and 4 repetitions for each treatment with standard management for the barriers. The research also studied the effect of contour hedgerows on the soil re-distribution of the slope in the precipitation process. SPSS 17.0 was used in the data analysis. The conclusions were listed as follows:(1) Contour hedgerow is an affordable option to the water and soil conservation in red soil region. Compared to the blank control, contour hedgerows could significantly ease the soil erosion on slopes especially by reducing the soil loss amount and surface run-off amount, and the double-row hedgerows are better than single hedgerows while MM is better than HH.(2) According to the 10 times natural rainfall witnessed from May 2009 to April 2010, the most serious soil erosion in the experimental area happened simultaneously with the heaviest rainfall between June and July; the soil loss amount in this period accounted for 60% in the yearly record, and it proved that the amount of rainfall was a key contributor in the soil erosion of this area.(3) MM reduced the average soil loss to 20% of the blank control while H could only make 52%, and the soil erosion controlling effect of MM was the best.(4) The surface runoff coefficient of MH was 29.66% while the bare slope's was 45.85%, although the other treats'were all above that of MH.(5) Taking surface run-off amount and corresponding soil loss amount as variables, the fitting curve of quadratic regression analysis showed that contour hedgerows desensitized the response of soil loss to the increase of surface run-off.(6) The REE tracing proved the noticeable effect of contour hedgerows in changing the soil re-distribution of the slope in the process of sedimentation, but it had little to do with the spatial distribution of soil erosion on slopes.
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