望天树人工幼林混交对土壤微生物功能多样性与碳源利用的影响  

Effects of mixed young plantations of Parashorea chinensis on soil microbial functional diversity and carbon source utilization

作　　者：李万年 罗益敏 黄则月 杨梅[1] LI Wan-Nian;LUO Yi-Min;HUANG Ze-Yue;YANG Mei(Guangxi Key Laboratory of Forest Ecology and Conservation,College of Forestry,Guangxi University,Nanning 530004,China;Guangxi Nanning Liangfengjiang National Forest Park,Nanning 530004,China;Forestry Pest Management and Quarantine Station of Yangzhou,Yangzhou,Jiangsu 225000,China)

机构地区：[1]广西大学林学院,广西森林生态与保育重点实验室,南宁530004 [2]广西南宁良凤江国家森林公园,南宁530004 [3]扬州市林业有害生物检疫防治站,江苏扬州225000

出　　处：《植物生态学报》2022年第9期1109-1124,共16页Chinese Journal of Plant Ecology

基　　金：国家自然科学基金(31960307);广西自然科学基金(2018GXNSFAA28110);广西研究生教育创新计划资助项目(YCBZ2022036)。

摘　　要：研究望天树(Parashorea chinensis)在幼龄阶段分别与巨尾桉(Eucalyptus grandis×E. urophylla)、降香黄檀(Dalbergia odorifera)混交对土壤微生物群落功能特征和碳源利用的影响,以期为濒危树种望天树人工林培育模式和桉树纯林改造中的树种选择提供科学依据。该研究采用Biolog-ECO技术对比分析了望天树混交林和纯林土壤微生物对6类碳源的利用特点和代谢活性,探讨微生物功能多样性的差异及与土壤环境因子的关系。结果表明:(1)望天树×巨尾桉混交林的Shannon-Wiener、Simpson和McIntosh多样性指数均最高,其土壤微生物功能多样性显著高于纯林;(2)望天树混交林的土壤微生物对碳源的利用能力和代谢活性及微生物数量高于纯林,并随土层加深而下降;混交林和纯林的土壤微生物对酚酸类碳源的利用程度均最高、胺类次之、多聚物最低,不同点在于混交林和纯林分别对氨基酸类、羧酸类碳源的依赖度更高;(3)望天树混交林土壤的含水率、总孔隙度以及有机质、全氮、全钾、铵态氮、硝态氮、速效磷、速效钾等养分含量高于纯林;并且除全磷和全钾外其他养分含量的垂直分布特征呈现出明显的表聚效应;(4)环境因子分析表明,土壤pH、有机质、全钾和速效钾含量是造成混交林和纯林间以及不同土层间土壤微生物功能多样性和碳源利用存在明显差异的主要驱动因子。综上所述,望天树混交造林模式对幼林土壤微生物群落及其生存环境有显著影响,尤其与巨尾桉混交可以有效提高土壤微生物代谢活性和功能多样性,促进凋落物和有机质的分解。与纯林相比,望天树混交林在一定程度上改善了土壤质量和肥力,为望天树幼树生长营造了较好的土壤环境和光照条件。Aims This study aimed to study the effects of two young mixed plantations of Parashorea chinensis(an endangered native tree species) on the functional characteristics and carbon source utilization of the soil microbial community,so as to select the suitable afforestation mode of P.chinensis and maintain sustainable management of forests by changing pure Eucalyptus plantation into mixed plantations with heterogeneous structure.Methods The functional diversity of soil microbes and their utilization of six carbon sources in mixed and pure plantations of P.chinensis were compared and analyzed using the Biolog-ECO technique,and a correlation analysis was further carried out incorporating soil physicochemical properties.Important findings(1) The Shannon-Wiener,Simpson and McIntosh diversity index of the microbe community in mixed plantations of P.chinensis and E.grandis × E.urophylla were the highest,and their soil microbial functional diversity was significantly higher than that of pure plantations.(2) The carbon source utilization and microbial quantity of soil microbes in the mixed plantations were higher than those in the pure plantation,and decreased with the deepening of the soil layer.The utilization of phenolic acid by soil microbes in mixed and pure plantations was the highest,followed by amines,with polymers at the lowest level,and the difference was that mixed and pure plantations were more dependent on amino acids and carboxylic acids,respectively.(3) The soil moisture conditions and the content of organic matter,total nitrogen,total potassium and available nutrients in the mixed forest of P.chinensis were higher.In addition,the vertical distribution of other nutrients except total phosphorus and total potassium showed obvious surface aggregation.(4) Environmental factors analysis showed that soil p H,organic matter and potassium were the main driving factors causing significant differences in soil microbial functional diversity and carbon source utilization between mixed and pure plantations,as well as di

关 键 词：望天树 幼林 土壤微生物 功能多样性 碳源利用 土壤养分 混交林 

分 类 号：S714[农业科学—林学]