岷江源区亚高山森林-高山草地生态系统界面土壤无机磷赋存特征及其影响因子  

Characteristics and influencing factors of soil inorganic phosphorus across the interfaces of sub-alpine forest–alpine meadow ecosystems at Minjiang headwaters

作　　者：石钰琛 宋怡珂 周俊[4] 盖艾鸿[1] 石凝 孙建 王金牛[2,7] 吴彦 SHI Yuchen;SONG Yike;ZHOU Jun;GAI Aihong;SHI Ning;SUN Jian;WANG Jinniu;WU Yan(College of Resources and Environmental Sciences,Gansu Agricultural University,Lanzhou 730070,Gansu,China;Chengdu Institute of Biology,Chinese Academy of Sciences,Chengdu 610041,Sichuan,China;Environment and Plant Protection Research Institute,Chinese Academy of Tropical Agricultural Sciences,Haikou 571101,Hainan,China;Chengdu Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610041,Sichuan,China;University of Chinese Academy of Sciences,Beijing 101408,China;Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100101,China;Mangkang Ecological Monitoring Station,Tibet Ecological Security Barrier Ecological Monitoring Network,Qamdo 854500,Tibet,China)

机构地区：[1]甘肃农业大学资源与环境学院,甘肃兰州730070 [2]中国科学院成都生物研究所,四川成都610041 [3]中国热带农业科学院环境与植物保护研究所,海南海口571101 [4]中国科学院水利部成都山地灾害与环境研究所,四川成都610041 [5]中国科学院大学,北京101408 [6]中国科学院青藏高原研究所,北京100101 [7]西藏生态安全屏障生态监测站网芒康生态站,西藏昌都854500

出　　处：《草业科学》2023年第3期603-615,共13页Pratacultural Science

基　　金：国家自然科学基金项目(31971436、41661144045);中国科学院西北生态环境与资源研究院冰冻圈国家重点实验室开放课题(SKLSOP-2018-07);中国生物多样性监测与研究网络(Sino BON)。

摘　　要：土壤无机磷是高寒生态系统有效磷的重要来源,研究亚高山森林-高山草地生态系统界面的土壤无机磷组分动态及其影响因素有助于深刻理解该生态系统的生物地球化学循环过程。本研究采用Tiessen修订的Hedley磷素分级法,分析了岷江源区卡卡山和斗鸡台亚高山森林-高山草地生态系统界面不同深度土壤(0-15和15-30 cm)无机磷组分的季节动态(生长初期、生长盛期、生长末期)和空间赋存特征及其主要影响因子。结果表明:1)不同形态土壤无机磷的含量受到生长期、植被类型及其交互作用的显著影响(P<0.05);斗鸡台土壤活性无机磷(NaHCO_(3)-Pi)含量在生长季初期最低;卡卡山草甸(56.0 mg·kg^(-1))、树种线(68.4 mg·kg^(-1))和密闭森林(65.7 mg·kg^(-1))土壤活性无机磷含量在生长季末期最高(P<0.05);两处生态系统界面的土壤中等活性无机磷(NaOH-Pi)含量在生长季末期均达到最高值(P<0.05)。2)密闭森林样带的土壤无机磷主要形态是活性无机磷,HCl-Pi是树种线样带土壤无机磷的主要形态,中等活性无机磷和残留无机磷(Residual-P)是草甸区土壤无机磷的主要形态。3)土壤有机碳、全氮、全磷、含水量、酸碱度以及土壤碳氮磷化学计量比与土壤无机磷组分含量显著相关(P<0.05)。研究结果表明,生长期、植被类型和土壤理化性质与无机磷组分的变化显著相关。Soil inorganic phosphorus is a key source of available phosphorus in alpine ecosystems.It is critical to study the dynamics and factors influencing soil inorganic phosphorus fractions across the interface between sub-alpine forest and alpine grassland ecosystem.This is useful to understand their biogeochemical cycle process.We analyzed the seasonal dynamics(the early,peak,and end growth stages)and spatial patterns of inorganic phosphorus fractions and the main factors influencing the soils at different depths(0-15 and 15-30 cm),across the interface between the sub-alpine forest and alpine grassland ecosystem at Kaka and Doujitai Mountains,respectively,of the Min River headwater region.The study was based on the Hedley phosphorus fraction method modified by Tiessen.We found that the content of soil inorganic phosphorus fractions was significantly influenced by growth periods,vegetation,and their interaction(P<0.05).Soil labile inorganic phosphorus(NaHCO_(3)-Pi)content was the lowest in the early growing season at Doujitai Mountain(P<0.05).Labile inorganic phosphorus content was the highest at the end of growing season in the alpine meadows(56.0 mg·kg^(-1)),tree species line(68.4 mg·kg^(-1)),and closed forest(65.7 mg·kg^(-1))of Kaka Mountain(P<0.05).Moderately labile inorganic phosphorus(NaOH-Pi)content reached the highest at the end of the growing season in both alpine interfaces(P<0.05).NaHCO_(3)-Pi and HCl-Pi were the main soil inorganic phosphorus forms at the closed forest and tree species line sites,respectively.Moreover,NaOH-Pi and residual inorganic phosphorus(Residual-P)were dominant in the alpine meadow area.Soil organic carbon,total nitrogen,total phosphorus,variable water content,pH,nitrogen and phosphorus stoichiometry ratios,and soil carbon were significantly correlated with the content of soil inorganic phosphorus fractions(P<0.05).The study results indicate that the growth period,vegetation type,and soil physical and chemical properties correlate significantly with a change in inorganic phosphoru

关 键 词：青藏高原 磷的有效性 树线交错带 生长时期 植被带类型 土壤理化性质 生态化学计量比 

分 类 号：S812.2[农业科学—草业科学]