Carbon and nitrogen status in litterfall of a red pine stand with varying degrees of damage from pine wilt disease

We evaluated the carbon (C) and nitrogen (N) status of litterfall in a natural red pine (Pinus densiflora) stand damagedby pine wilt disease in Jinju City, which was one of the areas severely affected by the disease in Korea. A significant correlation(P < 0.05) was found between tree density and basal area and the C and N status of litterfall components, but Cand N status was not correlated with mean diameter at breast height in the pine wilt disease stands. Needle-litter C andN concentrations were linearly related (P < 0.05) to basal area in pine wilt disease stands. Needle-litter C concentrationdecreased with a decrease in damage intensity due to pine wilt disease, whereas litter N concentration increased with anincrease of basal area in pine wilt disease stands. The linear regression equations developed for litterfall C and N inputswere significant (P < 0.05), with basal area accounting for 50-86% of the variation, except for cone and flower litter. Theresults indicated that the incidence of pine wilt disease could impact the quality and quantity of C and N in litterfall ofpine stands suffering from pine wilt disease.