Page 121 - 《广西植物》2023年第9期
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9 期 曹意等: 竹茶混交模式对表层土壤有机碳储量及组分的影响 1 6 6 9
Abstract: In order to explore the effects of planting tea trees under Phyllostachys edulis forest on soil organic carbon
storage and carbon componentsꎬ we took pure bamboo forestꎬ bamboo ̄tea mixed forest and evergreen broad ̄leaved forest
as the study objectsꎬ collected the surface soil (0-10 cm) of these three forest typesꎬ and measured soil organic carbon
(SOC)ꎬ carbon componentsꎬ biotic and abiotic factors. The results were as follows: (1) The diversity of understory
plants in bamboo ̄tea mixed forest was significantly lower than that in pure bamboo forestꎬ but there was no significant
 ̄2
differences in soil organic carbon density[ (22.54 ± 2.09) thm ] and carbon composition between bamboo ̄tea mixed
 ̄1
forest and pure bamboo forest (P>0.05). Mineral ̄associated organic carbon (MOC) was (20.13 ± 1.83) g kg ꎬ
accounting for 92.66% of total organic carbon. The soil organic carbon density of evergreen broad ̄leaved forest was
41.15% and 41.00% higher than that of bamboo ̄tea mixed forest and pure bamboo forest (P>0.05). (2) Soil microbial
biomass carbon (MBC) contentꎬ 16S rRNA gene abundanceꎬ cbbL gene abundance and microbial carbon use efficiency
 ̄1 10 10  ̄1 8 8
of these forest types were (0.58 - 3.08) gkg ꎬ (2.18× 10 - 5.65× 10 ) copiesg ꎬ (0.37× 10 - 1.10× 10 )
 ̄1
copiesg ꎬ 0.03 - 0.28ꎬ respectively. But there were significant differences about these microbial indicators between
three forest types (P>0.05). (3) SOC of the three forest types was significantly negatively correlated with soil pHꎬ
gravel content and aboveground litter biomassꎬ and significantly positively correlated with soil clay contentꎬ silt contentꎬ
total nitrogenꎬ C ∶ Nꎬ total phosphorus and ammonium nitrogen (P<0.05). (4) In terms of different carbon fractionsꎬ
particulate organic carbon (POC) and MOC were significantly negatively correlated with soil pHꎬ gravel content and root
biomassꎬ and significantly positively correlated with soil water contentꎬ clay contentꎬ silt contentꎬ total nitrogenꎬ C ∶ Nꎬ
total phosphorus and ammonium nitrogen (P<0.05). In conclusionꎬ the mixed transformation of bamboo and tea will
cause the decrease of understory vegetation diversity in the original pure bamboo forestꎬ but it will not cause the decrease
of soil carbon storageꎻ compared with evergreen broad ̄leaved forestꎬ it is necessary to improve the management measures
of bamboo to improve its carbon sink efficiency.
Key words: particulate organic carbonꎬ mineral ̄associated organic carbonꎬ soil orgnaic carbon densityꎬ Phyllostachys
edulis forestꎬ bamboo ̄tea mixed forest
随着“碳中和”目标的提出ꎬ未来 40 年中国会 叶林ꎬ毛竹的种植与入侵往往会造成对土壤碳储
实施更有力的政策减少碳排放、增加碳汇ꎮ 但是ꎬ 量的下降(Wang et al.ꎬ 2019ꎻ祁雪连等ꎬ2021)ꎬ同
合理政策的制定依赖于对增汇减排的科学认知ꎮ 时 引 起 颗 粒 有 机 碳 ( particulate organic carbonꎬ
土壤是陆地最大碳储存库ꎬ通过增加土壤碳储量 POC) 与 矿 物 结 合 态 有 机 碳 ( mineral ̄associated
被认为是实现“ 碳中和” 目标的有效途径( 杨元合 organic carbonꎬ MOC)含量与占比的变化( Yang et
等ꎬ2022)ꎮ 近自然造林以及植被恢复的土壤碳汇 al.ꎬ 2021b)ꎮ 不同的管理措施( 如间伐、林下植被
效应已经被广泛认知( Don et al.ꎬ 2011ꎻ Lu et al.ꎬ 清除) 和混交模式( 如竹-杉木混交) 会对毛竹林
2018)ꎬ如何提升经济林的土壤碳汇效益已成为当 土壤碳库产生不同的影响( 漆良华等ꎬ2013ꎻ李光
前关 注 的 热 点 ( Yang et al.ꎬ 2021bꎻ Villa et al.ꎬ 敏等ꎬ2019ꎻYang et al.ꎬ 2021a)ꎮ Yang 等(2021a)
2022)ꎮ 在浙江安吉的研究表明ꎬ粗放经营的毛竹林比无
毛竹( Phyllostachys edulis) 是我国价值较高的 经营和集约经营的毛竹林具有更高的团聚体稳定
竹类品种ꎬ广泛分布于南方山地丘陵地区ꎬ约占全 性和有机碳储量ꎮ 生物与非生物因素对毛竹土壤
国竹林面积的 74%ꎬ其主要经济价值在于生产竹 碳库影响因研究地区与经营管理措施不同也存在
材与竹笋( 杨传宝等ꎬ2020)ꎮ 毛竹在经济林种植 差异性(张厚喜等ꎬ2019ꎻYang et al.ꎬ 2021a)ꎮ
中占据重要地位ꎬ以及快速生长特性ꎬ使其碳汇效 目前ꎬ毛竹单一的经济收入模式难以满足农
益受到了广泛关注ꎮ 毛竹地上部分的年均固碳量 民收入水平提高的热切需求ꎮ 同时ꎬ近年来受竹
 ̄2
较 高ꎬ 为 ( 8. 13 ± 2. 15 ) Mg hm ( Yen & Leeꎬ 材加工业低迷的影响ꎬ毛竹种植户的积极性也备
2011)ꎮ 目前ꎬ主要围绕毛竹入侵与经营管理措施 受打击ꎮ 因此ꎬ发展林下经济成为了增加农户收
两个方面开展毛竹土壤碳库研究ꎮ 相较于常绿阔 入、推动毛竹产业可持续发展的重要举措( 蔡春菊