Agri-Engineering and Irrigation Technology for Hill Agriculture in Germany

Agricultural use in Germany ends at a slope angle of about 25%. For slope gradients >25% the exclusive use as grassland; first of all predominantly as meadow, then as pasture begins. At a slope angle of more than 45% the possibility of mechanized processing ends. On suitable locations crop growth up to a slope gradient of 60% is possible. Wine is an example; but here the slopes are more or less terraced. The agricultural use of slopeland increases the appearance of water erosion. In Germany altogether 28% of the arable land are endangered through water erosions. To decrease the erosion danger in maize, sugar beets, and occasionally also at cereals direct seed in dead plant residues (mulch), combined with non plough soil tillage is used more and more. Especially in low range mountains the drizzling-irrigation of spring water on grassland was wide spread in former times. Irrigation is an important instrument for stabilization and increasing yields. However, irrigation water is only in limited quantities available. Because of these limited water quantities, water saving irrigation systems are needed. One method is the transition of basin irrigation to sprinkler systems. Sprinkler irrigation requires no levelling of the irrigation farmlands. The employment of these machines has at least three disadvantages: 1. The machines demand relatively large farmlands; there the productivity can be raised noticeably. On the other hand small farm-structures are little suitable. 2. Usually high investments are necessary, combined with imports from industrialized countries. 3. On unfit locations the employment of modern sprinkler machines causes irrigation erosion. Irrigation erosion can appear, when the intensity of the artificial rain exceeds the infiltration intensity of the soil at the location. For the most of the sprinkler machines this fact applies.