A preliminary study of economic characters of mulberry planted within contour hedgerows of nitrogen fixing plants The recent development of technique of contour hedgerows Effects of straw mulching and Vetiver grass hedgerows on the size distribution of the soil water stable aggregates and aggregate-associated organic carbon in red soil The effect of hedgerows on the distribution of Harmonia axyridis Pallas in agroforestry systems Effect of Leucaena leucocephala on soil organic carbon conservation on slope in the purple soil area