Primorskaya State Academy of Agriculture, Ussuriysk, Russia
Forest litter is one of the main carbon pools in the forest. In this study, the stocks of forest litter in cedar plantations in the forest area of Primorskaya SAA have been determined. The study was carried out during three seasons - 2014, 2015, 2016. Forest plots with different average age of the dominant species were selected. The average tree ages in sample plots were 50, 80, 130 and 200 years. The litter was collected using a 25×25 cm frame in three replicates once every 1-2 weeks from April to November. At sites of 130 and 200 years, 7 catchers 0.5 m2 each were installed. The fall was collected monthly from September 2016 to August 2017.
The accumulation of litter continues year-round with a maximum in October during the period of massive leaf fall in deciduous species. The share of autumnal litter averaged 60%. In the period from November to July, the bulk of the litter is represented by needles of cedar and fir. The decomposition of the litter depends on the humidity and temperature in a certain period of time. To convert the litter stock into a mass of pure carbon, a coefficient of 0.37 was used. The average carbon content in the litter of the investigated forests was: 50 years - 4.25±0.13 t C / ha; 80 years - 4.21±0.11 t C / ha; 130 years - 4.59±0.16 t C / ha; 200 years - 5.25±0.19 t C / ha.
The ratio of the litter on the ground to the litterfall on both sites is characterized by the litter-fallow coefficient. For the maturing Pinus koraiensis forests, this ratio was 3.5 that indicates a high turnover rate of the matter in the litter.