晋北农牧交错带盐碱退化草地土壤-植物-微生物碳氮磷化学计量及其内稳性特征

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中图分类号：S812 文献标识码：A 文章编号：1007-0435（2025）11-3654-11

引用格式：，等.晋北农牧交错带盐碱退化草地土壤-植物-微生物碳氮磷化学计量及其内稳性特征[J]草地学报，2025，33（11）：3654—3664REN Guo-hua，YANG Rong-bang，CUI Li-yuan，et al.Stoichiometric Dynamicsand Homeostasis of Soil-Plant-MicrobialC，N，andPinSaline-Alkali Degraded GrassandsofNorthernShanxi'sAgro-PastoralEcotone[J].ActaAgrestiaSinica，2025，33（11） ：3654—3664

Stoichiometric Dynamics and Homeostasis of Soil-Plant-Microbial C，N， and P in Saline-Alkali Degraded Grasslands of Northern Shanxi's Agro-Pastoral Ecotone

REN Guo-hua， YANG Rong-bang， CUI Li-yuan ， LI Yan-ling ， YAO Meng-meng

（1.ColegeofGrasandien，aniAgriculturalUniversityig，aniProvince08ina；2.KeyaboratoryforodeltioninForageructioEfcyistrrilureduralisigaircein;iKb toryofGrassland Ecologicalrotectionand NativeGrassGermplasm Innovation，Taigu，ShanxiProvince O3080l，China）

Abstract：To explore the nutrient dynamics and stability mechanisms of saline-alkali degraded grassland ecosystems in the semi-arid agro-pastoral ecotone，this study examined grasslands with light，moderate，and severe saline-alkali degradation gragients in northern Shanxi.Changes incarbon（C），nitrogen（N），and phosphorus （P） contents，along with their stoichiometric ratios，were assessed within the soil-plant-microbe system. Coupling relationships between system components and characteristics of stoichiometric homeostasis were also analyzed.The results revealed that with increasing salinization severity，significantdeclines ocurred in soil Ncontent，plant C and N concentrations （in both shoots and roots），and microbial biomass C，N，and P（MBC， MBN，MBP）.In contrast，plant P content in both shoots and roots significantly increased. These changes resulting in reduced N：P and C：P ratios in soil and roots，as well as decreasing C：P ratios in shoots，indicating thatN limitation was intensified in the grasslands.The regulationof the ecological stoichiometric balance between plants and microbes was influenced by soil P availability and its ratios with C and N. Shoots exhibited stronger stoichiometric homeostasis than roots and microbes.For effctive ecological restoration of semi-arid saline-alkali degraded grasslands，management should focus onmitigating key nutrient limitations through scientific fertilization and enhancing ecosystem stability by introducing nitrogen-fixing plant species.

Key words：Agro-pastoral ecotone;Saline-alkali degraded grassland;Soil nutrients;Ecological stoichiometry

生态化学计量学致力于解析生态系统中各组分之间的能量平衡，以及碳（C）氮（N）磷（P）等元素的耦合关系与调控机制1，已成为研究地上-地下系统能量交换及物质循环的重要手段。（剩余22380字）