| 摘要: |
| 【目的】探究西双版纳两年生和三年生轻木（Ochroma lagopus）叶片非结构性碳水化合物（NSC）及碳（C）、氮（N）、磷（P）含量在雨季生长期间的季节变化，为该地区轻木人工林栽培管理提供理论依据。【方法】于6－8月、10月在云南西双版纳勐腊县勐醒农场两年生和三年生轻木人工林设置样地并进行取样，测定轻木叶片NSC及其组分可溶性糖和淀粉的含量，以及C、N、P含量及其比值。【结果】①两年生轻木叶片的可溶性糖和NSC含量均在7月最高，分别为103.60和151.15 mg/g，淀粉含量在8月最高（63.48 mg/g）。三年生轻木叶片的可溶性糖在6月最高（74.36 mg/g），淀粉和NSC含量在8月最高，分别为64.22和132.39 mg/g。7月，两年生轻木叶片的可溶性糖、淀粉、NSC含量及可溶性糖/淀粉值均极显著高于三年生轻木。②两年生轻木叶片C含量在10月最高（489.13 mg/g），三年生在7月最高（481.80 mg/g）；轻木叶片N含量均在10月最高，分别为8.76和9.31 mg/g；随季节变化三年生轻木叶片P含量先下降后上升。6月和10月，两年生轻木叶片C含量显著高于三年生轻木;6月，三年生轻木叶片N含量显著高于两年生轻木；在6,7和10月，三年生轻木叶片P含量极显著高于两年生轻木。两年生轻木叶片C/N值在7月最高，C/P和N/P值均在10月最高；三年生轻木叶片C/N在7月最高，C/P值在8月最高，N/P值在10月最高。两年生和三年生轻木叶片N/P值均小于14，表明轻木的生长受N限制。③轻木叶片NSC含量与C、N、P化学计量比之间具有不同程度的相关性。两年生轻木叶片N含量与可溶性糖和NSC含量呈显著负相关，P含量与淀粉含量呈显著负相关，N/P值与可溶性糖含量呈显著负相关。三年生轻木叶片C含量与可溶性糖含量呈极显著负相关;C/P值与可溶性糖含量呈显著负相关，与淀粉含量呈显著正相关。【结论】两年生和三年生轻木叶片NSC和C、N、P含量均表现出明显的季节变化，但两个林龄间又有一定的差异性。不同林龄轻木之间的差异受叶片NSC含量与C、N、P化学计量比之间动态平衡的影响。 |
| 关键词: 轻木 林龄 非结构性碳水化合物 碳氮磷化学计量 季节变化 云南西双版纳 |
| DOI：10.13207/j.cnki.jnwafu.2025.12.005 |
| 分类号: |
| 基金项目:国家自然科学基金项目（32071688） |
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| Seasonal variation of non-structural carbohydrates and C,N,P content in Ochroma lagopus leaves |
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LIU Chengyao1, XIAO Jiandong1, WU Junwen1, GU Jianyao1, DUAN Huaijiao1, DU Guanben2, LIU Youjun3
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1.College of Forestry,Southwest Forestry University,Kunming,Yunnan 650224,China;2.College of Materials and Chemical Engineering,Southwest Forestry University,Kunming,Yunnan 650224,China;3.Mengla County Mengxing Farm,Xishuangbanna,Yunnan 666304,China
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| Abstract: |
| 【Objective】The study aimed to investigate seasonal changes of non-structural carbohydrate (NSC) and the contents of carbon (C),nitrogen (N) and phosphorus (P) in leaves of two and three year old Ochroma lagopus plantations during the rainy season in Xishuangbanna,to provide a theoretical basis for the cultivation and management of Ochroma lagopus plantations in this area.【Method】Sampling plots were set during June to August and October in two year old and three year old Ochroma lagopus plantations at Mengxing Farm,Mengla County,Xishuangbanna,Yunnan Province.Leaf samples were collected to determine the contents of NSC,soluble sugars,starch,along with the concentrations of C,N,and P,and their stoichiometric ratios.【Result】① The contents of soluble sugar and NSC of two year old Ochroma lagopus were the highest in July,which were 103.60 and 151.15 mg/g,starch content was highest in August (63.48 mg/g).The soluble sugar content of three year old Ochroma lagopus leaves was the highest in June (74.36 mg/g),the starch content and NSC content were the highest in August (64.22 and 132.39 mg/g).In July,the contents of soluble sugar,starch,NSC and soluble sugar/starch ratio in leaves of two year old Ochroma lagopus were very significantly higher than those of three year old Ochroma lagopus.②The contents of C in two year old and three year old leaves were the highest in October (489.13 mg/g) and July (481.80 mg/g),respectively,and the contents of N in leaves were the highest in October (8.76 and 9.31 mg/g,respectively).With seasonal change,the P content of three-year Ochroma lagopus leaves decreased first and then increased.In June and October,the leaf C of two year old was significantly higher than that of three year old.In June,July and October,the leaf P of three year old was significantly higher than that of two year old.The highest C/N value of two year old Ochroma lagopus leaves was in July,and the highest C/P and N/P value were in October.Three year old leaves of Ochroma lagopus C/N value are highest in July,C/P value is highest in August,and N/P value is highest in October.In addition,the N/P values of two and three years old Ochroma lagopus leaves was less than 14,which indicated that the growth of Ochroma lagopus was restricted by N.③ Different degrees of correlation between NSC content and C,N and P stoichiometry in Ochroma lagopus leaves.There was a significant negative correlation between N content and soluble sugar and NSC content,and a significant positive correlation between P content and soluble sugar and NSC content;C/P values were significantly negatively correlated with soluble sugar content and N/P values were significantly negatively correlated with soluble sugar and NSC content.The C content of biennial Ochroma lagopus leaves showed a very significant negative correlation with soluble sugar and NSC content,and the P content and starch content.【Conclusion】Both two and three year old Ochroma lagopus leaves exhibited distinct seasonal variations in NSC content and C,N,P contents,with some differences between the two age groups.These differences among different ages of Ochroma lagopus were driven by the dynamic balance between NSC content and C,N,P stoichiometric ratios in leaves. |
| Key words: Ochroma lagopus forest age non-structural carbohydrate carbon,nitrogen,and phosphorus stoichiometry seasonal variations Xishuangbanna,Yunnan Province |
