학술논문

不同林龄白枪杆及土壤生态化学计量及非结构性碳特征研究 / Study on the Characteristics of Soil Ecological Stoichiometry and Non-Structural Carbon in Different Forest Ages of Fraxinus malacophylla
Document Type
Academic Journal
Source
核农学报 / Journal of Nuclear Agricultural Sciences. 38(2):364-373
Subject
林龄
叶片
土壤
生态化学计量
白枪杆
stand age
leaf
soil
ecological chemometrics
Fraxinus malacophylla
Language
Chinese
ISSN
1000-8551
Abstract
为了解不同林龄白枪杆(Fraxinus malacophylla)叶片-土壤氮磷钾特征、光合色素及非结构性碳含量的相互作用,以云南省建水县3种不同林龄(5、18和35年)白枪杆人工林为研究对象,每个林龄内设3个20 m×20 m的标准样方,测定不同土层(0~15、15~30、30~45 cm)和叶片N、P、K含量,叶片光合色素及非结构性碳含量;并计算叶片-土壤生态化学计量比,分析不同林龄白枪杆叶片和土壤N、P、K化学计量的变化规律及相互关系.结果表明,白枪杆叶片氮磷钾含量在中龄林内最高,幼龄林其次,成熟林最低;N∶P随着林龄的增大而显著增大,P∶K则相反;在幼中龄林内,白枪杆叶片N∶P值小于14,植物生长受N限制,在成熟林中大于16,植物受P限制;叶片可溶性糖与非结构性碳水化合物(NSCs)含量表现为幼龄林<中龄林<成熟林,而淀粉含量及光合色素(叶绿素a、叶绿素b、类胡萝卜素和总叶绿素)含量在中龄林内最高、幼龄林次之、成熟林最低.土壤N、P、K含量及N∶K在0~15和15~30 cm土层内随着林龄的增大而升高,在中龄林和成熟林中随着土层的加深而降低;同一土层中,N∶K在幼中龄林与成熟林间有显著差异(P<0.05).白枪杆叶片N∶P与15~30和30~45 cm土层的N∶P、N∶K呈显著正相关(P<0.05),而叶片N含量与不同土层N含量及叶片K含量与30~45 cm土层K含量呈显著负相关(P<0.05).因此,在幼中龄林时期,白枪杆人工林应注重N肥的施加,而在成熟林中应着重考虑P肥的补充.本研究结果为白枪杆林木养分补充及林分经营管理提供了理论依据.
The aim of our study was to understand the interactions among photosynthetic pigments and non-structural carbon content in leaves of Fraxinus malacophylla at different forest ages and soil's nitrogen,phosphorus,and potassium characteristics.Three artificial forests of F.malacophylla at different ages(5,18 and 35 years)were selected in Jianshui County,Yunnan Province,with three standard sample squares of 20 m×20 m within each stand.Our approach was to measure nitrogen(N),phosphorus(P)and potassium(K)contents in different soil layers(0-15,15-30,30-45 cm)and leaves,photosynthetic pigments and non-structural carbon contents in the leaves,and finally calculate ecological stoichiometry in the leaves and soil.In addition,we further analyzed the changes and interrelationships of N,P,and K stoichiometry in leaves and soil of different forest ages of F.malacophylla.Results showed that the N,P and K content in F.malacophylla leaves was the highest in the middle-aged forest,followed by the young forest,and the lowest was found in the mature forest.The ratio of N∶P significantly increases with the increase of forest age,while for P∶K was the opposite.In the young and middle-aged forest,the N∶P value in the F.malacophylla leaves was less than 14,and the plant growth was limited by nitrogen.While in the mature forest,the ratio of N∶P was greater than 16,and the plant growth was limited by P.The content of soluble sugars and non-structural carbon content in leaves under different forest ages followed the order:young forest