| 摘要: |
| 植被恢复被视为喀斯特石漠化区退化生态系统修复的核心策略，深入探究不同植被恢复模式下土壤-微生物量及其生态化学计量特征，对于科学评估这些恢复模式在改善土壤养分状况和促进生态系统恢复方面的效能具有关键作用。该研究以单一优良石山造林树种（任豆，Zenia insignis）恢复模式的纯林（Pure plantation, PP）、多树种（固氮树种+非固氮树种）恢复模式的混交林（Multi-species mixed plantation, MP）作为研究对象，以自然恢复的天然灌丛（Shrub land，SL）和地带性原生喀斯特森林（Natural forest, NF）作为对照，探究土壤-微生物量对喀斯特地区不同恢复模式的响应，并分析其生态化学计量比、微生物熵（qMBC、qMBN、qMBP）及化学计量不平衡性（C: Nimb、C: Pimb、N: Pimb）之间的关系。结果显示，PP和MP均有效提高土壤养分及微生物生物量的含量，且均表现出SL < PP < MP < NF的趋势；PP和MP除有机碳（SOC）：全磷（TP）外，土壤-微生物生物量化学计量比的比值均显著低于SL；PP和MP的qMBC、qMBN和qMBP均显著高于SL，而显著低于NF，并通过RDA和蒙特卡洛置换检验进一步得出微生物量碳（MBC）：微生物量氮（MBN）、N: Pimb和C: Nimb对微生物熵的影响最大。该研究结果表明，人工造林对退化的喀斯特石漠化地区进行恢复能加速改善了该地区的土壤养分状况，同时缓解了该地区植被恢复的土壤N、P限制，其中以引入多树种混交种植效果最佳。 |
| 关键词: 喀斯特地区 植被恢复 土壤养分 微生物生物量 生态化学计量 |
| DOI： |
| 投稿时间：2024-12-22修订日期：2025-01-23 |
| 基金项目:国家自然科学基金项目（面上项目，重点项目，重大项目）（32171755，31960240）；广西自然科学基金项目（2019GXNSFAA185023）；崇左凭祥友谊关森林生态系统广西野外科学观测研究站科研能力建设项目（桂科2203513003） |
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| Ecological Stoichiometry Characteristics of Soil-microbial under Different Restoration Models in Karst Desertification Region |
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LI Jiyin1, MA Hailun1, LIANG Yuying1, HE Qinxia1, HOU Danyang1, LUO Zhouyu1, WA Jing1, ZHENG Lu2, YOU Yeming1, HUANG Xueman1
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| (1.College of Forestry,Guangxi University;2.Experimental Centre of Tropical Forestry, Chinese Academy of Forestry) |
| Abstract: |
| Vegetation restoration is considered a core strategy for the rehabilitation of degraded ecosystems in karst rocky desertification areas. Investigating the soil-microbial biomass and their ecological stoichiometric characteristics under different vegetation restoration models plays a critical role in scientifically assessing the effectiveness of these restoration models in improving soil nutrient status and promoting ecosystem recovery. This study focuses on a single superior tree species (Zenia insignis) restoration model, with pure plantation (PP) and multi-species (N-fixing + non-N-fixing tree species) restoration model, with mixed plantation (MP), as the research subjects. Natural recovery sites, including shrub land (SL) and zonal native karst forests (NF), serve as controls. The study explores the response of soil-microbial biomass to different restoration models in karst areas, and analyzes the relationships between ecological stoichiometric ratios, microbial entropy (qMBC, qMBN, qMBP), and stoichiometric imbalance (C: Nimb, C: Pimb, N: Pimb). The results show that both PP and MP effectively increase soil nutrients and microbial biomass, with the trend SL < PP < MP < NF. Except for soil organic carbon (SOC): total phosphorus (TP), the soil-microbial biomass stoichiometric ratio of PP and MP is significantly lower than that of SL. The qMBC, qMBN, and qMBP values of PP and MP are significantly higher than those of SL, but significantly lower than those of NF. Further analysis using RDA and Monte Carlo permutation tests reveals that microbial biomass carbon (MBC): microbial biomass nitrogen (MBN), N: Pimb, and C: Nimb have the greatest impact on microbial entropy. These findings suggest that afforestation accelerates the improvement of soil nutrient conditions in degraded karst rocky desertification areas, while alleviating the N and P limitations of vegetation restoration in the region, with the multi-species mixed plantation model showing the best effect. |
| Key words: Karst region vegetation recovery soil nutrients soil microbial biomass ecological stoichiometry |
