PARENT SESSION
Poster Session #19: Nutrient Cycling.
Tuesday, August 7, 2001. Presentation from 3:30 PM to 5:00 PM. Exhibition Hall

Nutrient dynamics in litterfall and decomposition leaf litter in a mixed hardwood forest ecosystem, Korea.

KIM, CHOONSIG¹, CHOI, KYUNG¹, LIM, JONG-HWAN¹, SHIN, JOON-HWAN¹, OH, JEONG-SOO¹, ¹

ABSTRACT- Litterfall and litter decomposition represent a large and dynamic portion of nutrient cycling in forest ecosystem. We measured litterfall quantity and nutrient dynamics in decomposing litter in a mixed deciduous hardwood forest ecosystem for two years. Litterfall was collected in circular littertraps (collecting area : 0.25 m²)and mass loss rates and nutrient release in decomposing litter were estimated using the litterbag technique employing 30cm x 30cm nylon bags with 1.5mm mesh size. Total annual litterfall was 5,627kg/ha/yr and leaf litter account for 61% of the litterfall. The leaf litter quantity was highest in Quercus serrata, followed by Carpinus laxiflora and C. cordata. Q. serrata(67kg/ha/yr) was a major contributor of the nutrient(N, P, K, Ca, Mg)inputs in the site. Mass loss rates from decomposing litter were more rapid in C. laxiflora and C. cordata than in Q. serrata litter. About 77% and 84% of C. laxiflora and C. cordata litter disappeared, while 48% in Q. Serrata litter lost for two years. Lower mass loss rates of Q. serrata may be attributed to the difference of substrate quality such as lower nutrient concentrations compared with other two litter types. Nutrient concentrations (N, P, Mg) of three litter types except for potassium (K) increased compared with initial concentration over the study period. Increased nutrient concentration in decomposing litter was due to rapid loss of decomposing litter. The results suggest that litter mass loss and nutrient dynamic processes are considerably different among three species on same site condition.

KEY WORDS: Litterfall, Litter decomposition, Nutrient cycling, Nutrient dynamics