Organic chemical and nutrient dynamics in decomposing beech leaf litter in relation to fungal ingrowth and succession during 3‐year decomposition processes in a cool temperate deciduous forest in Japan

Abstract

Decomposition processes of beech leaf litter were studied over a 3‐year period in a cool temperate deciduous forest in Japan. Organic chemical and nutrient dynamics, fungal biomass and succession were followed on upper (Moder) and lower (Mull) of a forest slope. Litter decomposition rates were similar between the sites. Nutrient dynamics of the decomposing litter was categorized into two types: weight changes in nitrogen and phosphorus showed two phases, the immobilization (0–21 months) and the mobilization phase (21–35 months), while those in potassium, calcium and magnesium showed only the mobilization phase. The rate of loss of organic chemical constituents was lignin < holocellulose < soluble carbohydrate < polyphenol in order. The changes in lignocellulose index (LCI), the ratio of holocellulose in lignin and holocellulose, were significantly correlated to the changes in nitrogen and phosphorus concentrations during the decomposition. During the immobilization phase, increase in total fungal biomass contributed to the immobilization of nitrogen and phosphorus. The percentage of clamp‐bearing fungal biomass (biomass of the Basidiomycota) to total fungal biomass increased as the decomposition proceeded and was significantly correlated to LCI. Two species in the xylariaceous Ascomycota were dominantly isolated by the surface sterilization method from decomposing litter collected in the 11th month. The organic chemical, nitrogen and phosphorus dynamics during the decomposition were suggested to be related to the ingrowth, substrate utilization and succession of the Xylariaceae and the Basidiomycota. Twenty‐one species in the other Ascomycota and the Zygomycota isolated by the washing method were classified into three groups based on their occurrence patterns: primary saprophytes, litter inhabitants and secondary sugar fungi. These species showed different responses to LCI and soluble carbohydrate concentration of the litter between the groups.

Fungal community on decomposing leaf litter undergoes rapid successional changes

“…During the decomposition of Q. petraea leaves used in this study, approximately 70% of the total mass (Frankland, 1998;Osono and Takeda, 2001;Tang et al, 2005;Osono, 2007). The culture-dependent studies, however, tend to underestimate the total diversity of fungi and are biased towards rapidly growing species (Hering, 1967;Frankland, 1998).…”

Interaction of initial litter quality and thinning intensity on litter decomposition rate, nitrogen accumulation and release in a pine plantation

“…One postulated theory for our plots is that the microbial activity for N is mostly retained through microbial uptake during litter decomposition (Vitousek and Matson 1984;Hasegawa and Takeda 1996;Osono and Takeda 2001). The effect of microbial activity on N accumulation could also be altered by C availability (Hart et al 1994;Bradley et al 2000) and microclimatic conditions (Sinclair 1992;Aponte et al 2010).…”

Spatial and temporal diversity of wood decomposer communities in different forest stands, determined by ITS rDNA targeted TGGE

“…There were 12.4 species on average per sample. The highest species richness was detected in the native and oak forests (24 different species), followed by beech (23), Douglas-fir (22) and spruce (20 species). The native forest also had the highest average number of species present per sample (14), followed by oak (12.7), spruce (12.3), Douglas-fir (11.7) and lastly beech (11.3).…”

“…Even recalcitrant substrates, such as lignin, should degrade faster in diverse systems relative to simple ones, probably due to the complementary roles of different fungal species [26]. Fungal succession during litter decomposition has been recently studied for several forest floors under different tree species [22,27,31].…”