Depending on the amount, the type, the interval of application, and especially the characteristics of the soil, compost will improve soil structure and aggregate stability, hydraulic conductivity, infiltration, resilience against erosion, water hold­ing capacity, air balance, and soil temperature (Gerzabek et al. 1995; Hartmann 2003). Stabilization of soil aggregates by organic matter occurs in three main ways: (1) Application of organic matter maintains the microbial activity and thereby the production of metabolic products with cementing properties by microbial degra­dation, mature compost performing better than immature compost; (2) application of organic matter supports the activity of the soil microfauna and mesofauna, e. g., earthworms. Excrement aggregates have positive effects on the soil structure and influence the formation of wide macropores and generally enhance microbial acti­vity; (3) application of high molecular weight humic acids improves the long-term stability of microaggregates (Hartmann 2003; Fuchs et al. 2004). Annual applica­tions of small amounts of compost are more effective in stabilizing aggregates and pores size distribution than any singular application of high amounts (Lamp 1996).