Study On Soil Anti-erodibility Characteristics Of Red Soil Slope Land In South China Under Hedgerow Planted

In this research, we selected 14 anti-erodibility index data of 5 different hedgerow patterns in runoff plots to study the soil anti-erodibility. The soil anti-erodibility index system had been screened and the comprehensive soil anti-erodibility model had been built using the Principal Component Analysis. Meanwhile, the fittest hedgerow plant and its corresponding planting pattern using in the red soil slope land of South China had been selected by comparing the comprehensive soil anti-erodibility data of 5 different hedgerow patterns. The results are listed as follows1. The research indicated that the best soil anti-erodibility index system includes:dispersion rate, dispersion coefficient, the reunion situation, porosity, structural particle index, reunion degree, >0.5mm water stable aggregates,<0.05mm granule content and 0.001mm granule content.2. We got 3 principal components (Y1,Y2,Y3) by PCA. The liner expressions are:∧Y1=-0.500X1+0.303X2+0.709X3+0.226X4-0.525X5+0.029X6+0.702X7+0.645X8+0.561X9-0.646X10+0.875X11+0.566X12-0.930X13-0.718X14∧Y2=-0.763X1+0.232X2+0.417X3+0.726X4-0.489X5-0.011X6+0.592X7+0.598X8+0.766X9-0.614X10+0.440X11+0.816X12-0.288X13-O.605X14∧Y3=0.167X1-0.224X2-0.128X3-0.611X4+0.596X5+0.994X6-0.101X7-0.122X8-0.144X9+ 0.057X10-0.079X11-0.038X12+0.088X13+0.050X14According to the contribution rate of each component, we got the comprehensive soil anti-erodibility model:∧Y=0.3771∧Y1+0.3242∧Y2+0.1340∧Y33. By comparing the comprehensive soil anti-erodibility index data of different hedgerow planting patterns in runoff plots, we found that in red soil slope land of South China, the dwarf lilyturf is the best plant, and double-line planting is the best pattern. The double-line dwarf lilyturf can get the best soil conservation effect.4. By comparing the soil anti-erodibility of different slope sections, we found that the soil anti-erodibility:up-section> mid-section> down-section. So we suggest the relevant authorities should pay more attention to the up-section and down-section in the water and soil conservation work in red soil slope land of South China, especially the down-section. This research started from analyzing the soil anti-erodibility characteristics of red soil. Then we got the best hedgerow planting pattern in this area. The results showed that the reunion degree of red soil slope land of South China is quite high, but the aggregates are mainly>5mm. The content of water stable aggregates is a bit of low. These reasons make the anti-erodibility of red soil quite weak, and soil will be eroded easily by water. The soil erosion situation is very serious in this area. The research proves that:because the hedgerow has both ecological and economic functions, and its soil conservation ability is very strong. We suggest that the hedgerow should be widely used on the soil conservation. The results of this research have some guiding significance both on the soil conservation and hedgerow technique promotion work in South China. The double line dwarf lilyturf planting pattern can make the best ecological and economic benefit in the red soil slope land of South China. This planting pattern should be promoted widely in this area.