藏东南原始暗针叶林土壤呼吸及其影响因子分析

【目的】探讨藏东南原始林土壤呼吸特征,为加深对藏东南亚高山森林生态系统土壤碳循环过程及其关键驱动因子的了解。【方法】]对色季拉山东坡林芝云杉林和急尖长苞冷杉林土壤理化特性、土壤呼吸速率及其相关环境因子进行了研究,分析了两种原始林土壤呼吸速率的变化规律及影响因子。【结果】(1)林芝云杉林和急尖长苞冷杉林土壤呼吸速率昼夜变化分别为“双峰”和“单峰”曲线,日平均土壤呼吸速率分别为3.92μmol.m-2.s-1和3.49μmol.m-2.s-1;林芝云杉林土壤呼吸速率对温度的响应较急尖长苞冷杉敏感。(2)土壤温度和含水率是影响两种林分土壤呼吸速率并造成差异的首要因子;白天土壤温度的影响力更大,而夜间则为土壤含水率。(3)土壤有机碳含量高会促进土壤呼吸速率,而土壤微生物量碳的作用则相反。【结论】西藏暗针叶林生长季土壤呼吸主要受土壤温度和水分调控,也与土壤有机碳和微生物量碳密切相关。     

The Investigation of Relationships Between Some Fruit and Kernel Traits with Canonical Correlation Analysis in Ankara Region Walnuts

Canonical correlation analysis is a multivariate technique, which is employed to examine relationships between two variable sets, each of that consist of two or more variables. In the analysis, by maximizing the relationships between two sets, it is aimed to obtain new variables called as canonical variates that formed by linear combinations of the original variables for each sets. In this study, it is aimed to examine the relationships between some fruit and kernel characteristics of Ankara region walnuts. Thus, the following eight traits Fruit Length (mm), Fruit Width (mm) Fruit Height (mm) Fruit Weight (g), Shell Thickness (mm), Kernel Weight (g), Kernel Ratio (%) and Filled-firm Kernel Ratio (%) of 364 walnut samples were measured. First five of these characteristics were grouped as X variable and the rest of as Y variable. As a result, the correlation between the first canonical variable pair was found as 0.979 (p?<?0.01).