Der Einfluss der Wasserbindung und der Bodenstruktur auf das Wachstum von Fichtenkeimlingen

Birmensdorf

1958

S. 1-34

6 Abb., 14 Tab., 14 Lit. Ang.

Bandaufführung

157653

In dense, slowly permeable and imperfectlydrained forest soil germination and growth of seedlings are strongly affected by variation in soil structure and moisture content. In Switzerland such soils are often found on parent materials from the shaly Flysch beds. The independent effects of soil structure and moisture tension (see figure 3) on germination and growth of seedlings were investigated. The test soil was "Zugberg II", a poorly aeratedloam (see figures 1/2), neutral in reaction, ans containing 0,5% organic matter, and little macro-pore space. The structure was midified by addition of 0,2% and 1,0% "Krilium", a soil conditioner, to give three grades of structure: untreated, 0,2% "Krilium"-structure, and 1,0% "Krilium"-structure. Spruce (Picea abies) was used as a test species. Its root system is very sensitive to imperfectly drained soils and, moreover, in practise, this species is widely planted on such soils. "Krilium", as a compund, was found to have no adverse effect on seed germination (see tables 4/5). Germination of spruce seed and seedling mortality: Germination, the untreated soil held at 0,020 atm. tension, germination was reduced by 45%. At higher tensions, 0,080 and 0,160 atm., germination was normal. On the "Krilium"-conditioned soils germination was normal even at the lowest tension 0,020 atm. Mortality: Seedling mortality was 58% on the untreated soil at 0,020 atm. With a higher percentage of air-filled pores, brought about by higher tensions or "Krilium" treatment, mortality was reduced to 8 to 20 %.