tailieunhanh - Báo cáo lâm nghiệp: "Diurnal and seasonal fluctuations in the bark respiration of standing Quercus acutissima trees in Nakaizu, Japan"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài: Diurnal and seasonal fluctuations in the bark respiration of standing Quercus acutissima trees in Nakaizu, Japan. | 529s Ann. Sci. For. 1989 46 suppl. 529s-531s Forest Tree Physiology E. Dreyer et al. eds. Elsevier INRA Diurnal and seasonal fluctuations in the bark respiration of standing Quercus acutissima trees in Nakaizu Japan Y. Kakubari Laboratory of Silviculture University of Shizuoka Shizuoka Japan Introduction To compare annual carbon balances among different types of forest exosystems or to study the relationship between photosynthetic production and tree growth the amount of carbon fixed in photosynthesis and the respiratory loss by woody organs must be known approximately. The amount of information about bark respiration in field studies of woody organs of trees is especially limited. In situ measurements on stem respiration rates in trees have been made by Johansson 1933 Negisi 1975 Linder and Troeng 1981 Havranek 1985 and Kakubari 1988 . As a first step the diurnal and seasonal fluctuations in bark respiration from the stem were measured in standing trees of red oak Quercus acut-issima in Nakaizu Shizuoka Pref. Japan. Materials and Methods The measurements of bark respiration were performed from March 1986 to May 1987 in a 19 yr old coppice stand felled 3 times before in Nakaizu N 34 58 E 139 i altitude 320 m about 95 km northeast of Shizuoka. The general climate is characterized by abundant rainfall approximately 3700 mm annually and the Table I. General structure and location of bark respiration chambers. Sample tree Respiration chambers DBH cm H m No. H m Diam. cm Vol. ml d 1 1057 2 1079 d 0 3 227 4 699 5 1022 6 1418 7 1401 s 0 8 1408 530s annual average air temperature is c. Bark respiration was measured in 8 parts of stem bark at different heights of dominant d and suppressed s trees located at the edge o and within the stand Table I . The respiration chambers were enclosed with plates of stainless-steel forming cylinders. Air was circulated over the .