Construction drawings and design drawings of land improvement projects for water and soil loss control, including the current situation of land improvement projects combined with water and soil loss control, design drawings of typical fields, cross sections of horizontal terraces, cross sections of irrigation and drainage canals, water drop cross sections, plans of irrigation culverts and outlets, reinforcement drawings of irrigation culvert cover plates, cross sections of agricultural ditches and falls, aqueduct structure drawings, layout plans of barrages, Reservoir structure