Page 77 - 《广西植物》2026年第6期
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9 9 2 广 西 植 物 46 卷
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LIANG Yuying ꎬ HE Qinxia ꎬ LI Jiyin ꎬ MA Hailun ꎬ HUANG Haimei ꎬ ZHENG Jiamin ꎬ
2ꎬ3 2ꎬ3 1ꎬ3 1ꎬ3∗
MING Angang ꎬ WANG Qingling ꎬ HUANG Xueman ꎬ YOU Yeming
( 1. Guangxi Key Laboratory of Forest Ecology and Conservationꎬ Guangxi Colleges and Universities Key Laboratory for Cultivation and Utilization
of Subtropical Forest Plantationꎬ College of Forestryꎬ Guangxi Universityꎬ Nanning 530004ꎬ Chinaꎻ 2. Experimental Centre of Tropical Forestryꎬ
Chinese Academy of Forestryꎬ Pingxiang 532600ꎬ Guangxiꎬ Chinaꎻ 3. Guangxi Youyiguan Forest Ecosystem Observation and Research Stationꎬ
Youyiguan Forest Ecosystem Observation and Research Station of Guangxiꎬ Pingxiang 532600ꎬ Guangxiꎬ China )
Abstract: Ecological stoichiometry primarily investigates the proportional relationships of chemical elements between
organisms and their environment within ecosystems. It serves as a foundation for understanding life activities and
ecosystem functions. The study of soil ̄microbial biomass and their ecological stoichiometric characteristics of different
types of tree species in karst areas is crucial for scientifically assessing the effectiveness of various tree types in improving
soil nutrient conditions and optimizing tree species configuration strategies. This study was conducted in Daqingshan
Stone Mountain Arboretum at the Experimental Center of Tropical Forestryꎬ Chinese Academy of Forestry. Five nitrogen ̄
fixing tree species (N ̄fixer) and seven non ̄nitrogen ̄fixing tree species (non ̄N ̄fixer) were taken as study objects. The
research investigated the response patterns of soil ̄microbial carbon (C)ꎬ nitrogen (N) and phosphorus (P) contents to
N ̄fixer and non ̄N ̄fixer in karst ecosystems. It also analyzed ecological stoichiometric ratiosꎬ microbial quotient (qMBCꎬ
qMBN and qMBP)ꎬ and soil ̄microbial stoichiometric imbalance (C ∶ N ꎬ C ∶ P and N ∶ P ). The results
imb imb imb imb imb imb
were as follows: (1) The total nitrogen (N ) content and total phosphorus (P ) content of the soil in N ̄fixer tree
soil soil
species were significantly higher than that in non ̄N ̄fixerꎬ but C ∶ N was significantly lower than that in non ̄
soil soil
nitrogen ̄fixer. (2) The contents of microbial biomass carbon (MBC)ꎬ microbial biomass nitrogen (MBN) and microbial
biomass phosphorus ( MBP ) were significantly higher in N ̄fixer than in non ̄N ̄fixer . In contrastꎬ the ratios of
MBC ∶ MBP and MBN ∶ MBP were significantly lower in N ̄fixer than in non ̄N ̄fixer. No significant differences were
observed between N ̄fixer and non ̄N ̄fixer for C ∶ N ꎬ C ∶ P and N ∶ P ꎬ indicating that they were
imb imb imb imb imb imb
characterized by a certain degree of internal stability. (3) qMBC of N ̄fixer was significantly larger than that of non ̄N ̄
fixerꎬ while qMBN and qMBP showed no significant difference between these two types of tree species. The RDA results
showed that C ∶ P ꎬ MBN ∶ MBP and C ∶ N were the key factors influencing soil microbial quotient. This study
soil soil soil soil
indicates that compared with non ̄N ̄fixerꎬ N ̄fixer has significant advantages in improving soil nutrient status and
alleviating soil P limitation in karst areasꎬ which provides an important scientific basis for the selection of tree species in
the process of ecological restoration.
Key words: karstꎬ nitrogen ̄fixing tree species ( N ̄fixer )ꎬ ecological stoichiometric ratiosꎬ microbial quotientꎬ
stoichiometric imbalance
喀斯特石漠化是指土壤严重水土流失、基岩 使生态修复难度很大( 黄甫昭等ꎬ 2021)ꎮ 在喀斯
大面积裸露、土壤生产力急剧下降的土地退化现 特地区引入适宜的优质树种ꎬ不仅能够改善土壤
象ꎬ在脆弱的岩溶地质生态环境中因不合理的、集 环境ꎬ提升土壤有机质含量和肥力ꎬ还可有效涵养
约化的土地利用而造成(Chen et al.ꎬ 2019)ꎮ 中国 水源、减少水土流失ꎬ为其他植物的定植和生长创
西南喀斯特地区是世界三大岩溶集中分布区中岩 造有利条件ꎬ从而促进喀斯特地区的生态修复( 罗
溶作用最为强烈的地区ꎬ近年来该地区的石漠化 攀等ꎬ2017ꎻYu et al.ꎬ 2025)ꎮ
现象持续扩展ꎬ生态系统功能明显退化ꎬ不仅削弱 土壤 中 碳 ( carbonꎬ C)、 氮 ( nitrogenꎬ N) 和 磷
了生态系统的抗干扰能力ꎬ也制约了社会经济的 (phosphorusꎬP) 是植物和微生物生长的基本养分
发展(王克林等ꎬ2019)ꎮ 与非喀斯特地区相比ꎬ喀 元素(庞圣江等ꎬ2015)ꎮ 此外ꎬ养分的生态化学计
斯特地区具有岩石裸露率高、土层浅薄且不连续、 量比也是评估土壤养分供给能力的关键指标ꎬ为
土壤富钙偏碱、养分总量不足且易流失等特征ꎬ致 揭示喀斯特地区土壤元素的循环与平衡机制提供

