YANG Yu-sheng, CHEN Guang-shui, XIE Jin-sheng, YU Xin-tuo

(Fujian College of Forestry, Nanping, Fujian 353001, China)

Abstract: The trasferrence of nutrient elements caused by three different harvest ing systems of complete-tree harvesting, whole-tree harvesting and conventional harvesting under the third rotational stand of Chinese fir were compared in this paper . The result indicated that the loss of nutrient elements due to complete-tree and whole-tree harvesting was 1.99 and 1.64 times that of due to conventional harvesting, respectively. Slash burning resulted in great loss of N and P₂O₅ in forest ecosystem. The loss of N and P₂O₅ from stands due to adopting conventional silvicultural system (harvesting and following burning) was both higher than tha t of whole-tree and complete-tree harvesting without burning. Thus, shortening rotation length may cause serious deficiency of site N and P₂O₅ on site. Complete-tree and whole-tree harvesting can cause substantial base ion removal from the stand and resulted in seriously soil acidification.

Keywords: whole-tree harvesting; conventional harvesting; burning; Chinese fir stand; nutrition loss