What are the fish pond-terrace production mode and the mulberry pond production mode?

in the heavy saline-alkali land where agricultural planting is impossible, according to the principle of digging ponds (digging ditches) to infiltrate saline-alkali, digging ponds to build terraced fields, so that the constructed terraced fields can become saline-alkali-free fertile fields after saline-alkali infiltration, planting various crops or establishing mulberry planting bases to raise silkworms, etc., and then raising fish in ponds, which is a good successful model for transforming saline-alkali land.