�ber h�chstwerte der produktion von nat�rlichen Pflanzenbest�nden in N.O. Asien

Abstract

On maximal production values in natural plant communities. The intensity of photosynthesis is considered of less importance for the level of primary production (contrary to the general opinion of plant physiologists). Instead the assimilate houschould', the carbohydrate allocation, is considered decisive, i.e. the contribution of assimilates used for the development of photosynthetically active leaf-area. Compare a Fagus sylvatica seedling producing 1,5 g of dry matter in its first year, with a Helianthus annuus plant reaching 600 g. High netto primary production values can be expected in stands of tall forbs with a prolonged vegetative development under optimal moisture and nitrogen conditions. The production of giant forb communities in Camchatka and Sakhalin is discussed on the basis of Russian and Japanese publications. Environmental conditions in both areas are described. In river flood plains on Camchatka the forbs Filipendula camtschatica, Senecio cannabifolius and Heracleum dulce reach 3,5 m height. The phytomass production is 31 t/ha, of which 22 t/ha is subterranean. In river flood plains on Sakhalin Filipendula is accompanied by Polygonum sachalinense and many other species, reaching 4,5 m: The netto primary production may reach 40 t/ha/yr (10 t/ha/yr subterranean).