Changes in the relationship between tree size and aboveground respiration in field-grown hinoki cypress (Chamaecyparis obtusa) trees over three years.
Changes in the relationship between tree size and aboveground respiration in field-grown hinoki cypress (Chamaecyparis obtusa) trees over three years.
复制标题
三年来田间种植的扁柏 (Chamaecyparis obtusa) 树木大小与地上呼吸之间关系的变化。
DOI：
10.1093/treephys/18.1.37
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发表时间：
1998
期刊：
影响因子：
4
通讯作者：
A. Hagihara
中科院分区：
文献类型：
--
作者：
T. Yokota;A. Hagihara
在三年的野外条件下对 18 年生扁柏 (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.) 树的地上部分进行了呼吸测量，以研究呼吸与植物量、植物量增量和叶量之间随树龄变化的关系。年呼吸量（r（a））和植物质量（w（T））之间的关系近似为比例函数（r（a）= aw（T）），其中比例常数（a）逐年减少。时间对每棵样本树的年呼吸和植物质量之间关系的影响通过幂函数拟合。受树冠抑制的树木呼吸作用逐年减少，而其他树木的呼吸作用则随年龄略有增加。年呼吸量和叶质量之间的关系也可以通过广义幂函数来近似。排除被抑制的树木，年呼吸量（r（a））与地上植物量年增量（Deltaw（T））之间的关系用比例函数（r（a）= 2.27Deltaw（T））来描述，其中比例常数2.27与样本树和年份无关，表明每年呼吸量约为年地上植物量增量当量的2.3倍。对于任何树木，不同大小树木的年呼吸与叶质量和植物质量增量之间的时间常数关系与相应的时间连续体关系相似。相反，年呼吸量与植物质量之间的时间连续关系与时间常数关系不同，表明不太活跃的木本组织的呼吸对地上呼吸的贡献显着。根据树木大小与年呼吸量的关系，连续三年地上林分年呼吸量分别为25.0、26.9和25.8 Mg(dm) ha(-1)年(-1)，相应的地上林分生物量为60.0、69.0和76.8 Mg(dm) ha(-1)。
Respiration measurements of aerial parts of 18-year-old hinoki cypress (Chamaecyparis obtusa (Sieb. et Zucc.) Endl.) trees were made under field conditions over three years to study changing relationships with tree age between respiration and phytomass, phytomass increment, and leaf mass. The relationship between annual respiration (r(a)) and phytomass (w(T)) was approximated by a proportional function (r(a) = aw(T)), where the proportional constant (a) decreased year by year. The effect of time on the relationship between annual respiration and phytomass of each sample tree was fitted by a power function. Respiration of the tree suppressed by the canopy decreased year by year, but respiration of the other trees increased slightly with age. The relationship between annual respiration and leaf mass was also approximated by a generalized power function. Excluding the suppressed tree, the relationship between annual respiration (r(a)) and the annual increment of aboveground phytomass (Deltaw(T)) was described by a proportional function (r(a) = 2.27Deltaw(T)), where the proportional constant, 2.27, was independent of sample tree and year, indicating that about 2.3 times of the annual aboveground phytomass increment equivalent was respired annually. For any tree, the time constant relationships between annual respiration and leaf mass and phytomass increment for different-sized trees were similar to the corresponding time continuum relationships. In contrast, the time continuum relationship between annual respiration and phytomass differed from the time constant relationship, indicating that respiration of less active woody tissue contributed significantly to aboveground respiration. Based on the relationship between tree size and annual respiration, annual aboveground stand respiration was estimated to be 25.0, 26.9, and 25.8 Mg(dm) ha(-1) year(-1) for the three consecutive years, respectively, and the corresponding aboveground stand biomass was 60.0, 69.0, and 76.8 Mg(dm) ha(-1).