大别山五针松半天然林不同根级细根解剖结构特征

Anatomical Structure Characteristics of Fine Roots at Various Levels in Semi-Plantation of Pinus dabeshanensis in Different Ages

以岳西县妙道山林场10、20、30年生大别山五针松半天然林的1~5级细根为研究对象,采用石蜡切片方法对不同林龄树种的1~5级细根解剖结构进行观察统计,从而揭示不同林龄树种根序细根解剖结构的差异。研究表明,大别山五针松的细根直径、皮层厚度和维管束直径均随根序的增加而增加,同时,不同林龄相同根序的细根直径、皮层厚度、维管束直径和维根比之间也存在差异。样本解剖发现,该树种前5级根解剖结构存在明显差异,其中,在1~3级根解剖结构中可以清晰发现皮层结构,而4~5级根皮层结构消失,由此可以说明该树种1~3级细根属于初生结构,主要承担吸收功能,而4~5级细根属于次生结构,主要承担养分运输功能。本文研究对揭示大别山五针松地下生态学规律具有重要意义。

Taking grade 1~5 fine roots of the 10,20 and 30 years old Pinus dabeshanensis as the research object in seminatural forest,Miaodaoshan Forest Farm of Yuexi County,the paraffin section method was used to analyze the fine roots of Pinus dabeshanensis of different ages.The root anatomical structure was observed and counted,and the differences in the fine root anatomical structure of different root sequences of Pinus dabeshanensis sylvestris in different forest ages were studied.The results showed that the fine root diameter,cortex thickness,and vascular bundle diameter of Pinus dabeshanensis all increased with the increase of root sequence,and there are differences between the fine root diameter,cortex thickness,vascular bundle diameter and wiegand ratio of the same root sequence of different forest ages.The anatomy of the sample revealed that there are obvious differences in the anatomical structure of the 5 grade roots of Pinus dabeshanensis.Cortical structure can be clearly found in the anatomical structure of roots at grades 1 to 3,while the cortical structure of roots at grades 4 to 5 disappeared.Therefore,it can be explained that the fine roots of grade 1~3 of Pinus dabeshanensis belong to the primary structure and mainly undertake the absorption function,while the fine roots of grade 4~5 belong to the secondary structure and mainly undertake the function of nutrient transportation.The study is of great significance for understanding the underground ecology of Pinus dabeshanensis.