[目的]探索三江源区高寒草甸草地植被-土壤系统生物量和土壤养分的动态变化,以利于草地适应性管理和开展草地生态修复相关工作.[方法]以中度退化高寒草甸为研究对象,于2020-2022年的7、8和9月持续观测高寒草甸植被生物量(地上生物量和根系生物量)、植被(地上部和根系)和土壤(0～15和15～30 cm)全氮、铵态氮、硝态氮、速效氮、有机碳、全磷和全钾含量.植被生物量、植被养分和土壤养分在不同月份间的动态变化用单因素方差分析(One-way ANOVA)进行比较.[结果]不同月份间植被生物量存在显著的递增趋势(2021年除外)(P＜0.05,下同),整体表现为9月最大,地上生物量最大值分别为74.58和72.80 g/m2,根系生物量最大值分别为39.82和57.32 g/m2.植被(地上部和根系)和土壤(0～15和15～30 cm)养分含量存在显著的月际动态,具体表现为8月达到最大值.植被生物量与植被地上部和根系的全氮含量显著相关,与土壤0～15和15～30 cm土层的全氮含量呈显著正相关.[结论]高寒草甸植被(地上部和根系)养分与土壤(0～15和15～30 cm 土层)养分在8月达到峰值.研究结果可为高寒草甸养分管理领域学者凝练科学问题提供参考.
Dynamic changes of vegetation biomass and nutrients in degraded alpine meadows in the Sanjiangyuan area
[Objective]To explore the dynamic changes of vegetation-soil system biomass and soil nutrients in alpine meadows in the Sanjian-gyuan area is favorable for the adaptive management of grassland and the related work of grassland ecological restoration.[Method]Vegetation biomass(aboveground biomass and root biomass),vegetation(aboveground and root system)and soil(0-15 and 15-30 cm)contents of total nitrogen,ammonium nitrogen,nitrate nitrogen,quick-acting nitrogen,organic carbon,total phosphorus and total potassium of alpine meadows were consistently observed from 2020 to 2022 during the months of July,August and September in the moderately degraded alpine meadows as the research objects.The dynamics of vegetation biomass,vegetation nutrients and soil nutrients were compared between months using One-way ANOVA.[Result]There was a significant incremental trend(P＜0.05,the same as below)in vegetation biomass between months(except for 2021),with an overall maximum in September,with maximum values of 74.58 and 72.80 g/m2 for aboveground bio-mass and 39.82 and 57.32 g/m2 for root biomass,respectively.Significant inter-monthly dynamics existed between vegetation(aboveground and root system)and soil(0-15 and 15-30 cm)nutrient contents,as evidenced by the maximum values in August.Vegetation biomass was significantly correlated with total nitrogen content of vegetation aboveground and root system,and positively(P＜0.05)correlated with total nitrogen content of soil in the 0-15 and 15-30 cm layers.[Conclusion]Nutrients of alpine meadow vegetation(aboveground and root system)and soil(0-15 and 15-30 cm soil layers)reach the peak in August.The results of the study can provide a reference for scholars in the field of alpine meadow nutrient management to crystallize scientific issues.
The Sanjiangyuan areaAlpine meadowDegraded grasslandNutrient contentSoil physical and chemical properties
NETL
NSTL
万方数据
