摘要
西北荒漠区作为中国典型的生态脆弱区,藻结皮在其中扮演着重要的固碳角色,对维持区域碳平衡和生态功能具有重要意义。然而,目前关于西北荒漠区藻结皮覆盖下土壤有机碳(SOC),特别是其组分颗粒态有机碳(POC)和矿物结合态有机碳(MAOC)含量的垂直分布特征,以及关键影响因素仍缺乏明确的认识。本研究通过测定西北荒漠区藻结皮覆盖下0~2、2~5、5~10、10~20 cm土层SOC、POC和MAOC含量,并以裸沙为对照,结合相关影响因子,阐明SOC组分垂直分布特征及影响因素。结果表明:藻结皮SOC、POC和MAOC含量在各土层均高于裸沙,其中,SOC组分在0~2 cm土层差异尤为显著。藻结皮的POC和MAOC含量随土层深度增加而降低,POC含量由结皮层的3.83 g·kg^(-1)降至10~20 cm土层的2.37 g·kg^(-1),MAOC含量则从2.97 g·kg^(-1)降至0.95 g·kg^(-1)。在藻结皮和裸沙中,POC含量占比均高于MAOC含量占比;裸沙POC含量占比高于藻结皮,而藻结皮的SOC稳定性则高于裸沙。相关性分析表明,藻结皮与裸沙POC和MAOC含量受气候因子与土壤理化性质的综合影响,其中,SOC组分含量与全氮、铵态氮和速效磷含量显著正相关,而与p H和年均气温显著负相关。此外,年均气温和年均降水量是预测POC和MAOC含量的重要因素,其中年均气温对藻结皮POC含量预测的贡献度高达45.50%。本研究揭示了藻结皮在中国西北荒漠区的固碳作用,可为干旱区碳储量评估与碳汇管理提供科学依据。
The Northwest desert region of China,as a typical ecologically fragile area,where cyanobacterial crust plays cyanobacterial crust playing a crucial carbon-sequestration role,significantly maintaining regional carbon balance and ecological function.Nevertheless,the vertical distribution characteristics of soil organic carbon(SOC)under cyanobacterial crust,especially its fractions(particulate organic carbon(POC)and mineralassociated organic carbon(MAOC))and their key influencing factors in this region,are not yet clearly understood.This study measured the SOC,POC,and MAOC content in the 0-2,2-5,5-10,and 10-20 cm soil depths under cyanobacterial crust in the Northwest desert region,used bare sand as a control,and combined with relevant influencing factors,to clarify the vertical distribution characteristics of SOC components and their influencing factors.The results showed that the SOC,POC,and MAOC content of cyanobacterial crust in each soil depth were higher than those of bare sand,with the most significant differences in the O-2 cm soil depth.In cyanobacterial crusts,the content of POC and MAOC decreases with soil depth.POC content decreased from 3.83 g·kg^(-1)at the crust layer to 2.37 g·kg^(-1) in the 10-20 cm soil depth,and the MAOC content decreased from 2.97 g·kg^(-1) to 0.95 g·kg^(-1).In both cyanobacterial crust and bare sand,the proportion of POC content was higher than that of MAOC.The proportion of POC content in bare sand was higher than that in cyanobacterial crust,while the SOC stability of cyanobacterial crust was higher than that of bare sand.Correlation analysis showed that the POC and MAOC content of cyanobacterial crust and bare sand were affected by a combination of climatic factors and soil physicochemical characteristics.In the case of soil organic carbon fractions,they had a significantly positive correlation with total nitrogen,ammonium nitrogen,and available phosphorus,but a significantly negative correlation with pH and mean annual temperature.In addition,mean annual temperature and precipitation were important factors for predicting POC and MAOC content,with mean annual temperature alone contributing 45.50%to predicting POC content in cyanobacterial crusts.This study reveals the carbon-sequestration role of cyanobacterial crust in the Northwest desert region of China,providing a scientific basis for carbon-stock assessment and carbon-sink management in arid region.
作者
杜蕃
杨军刚
郭星
陆永兴
陶冶
尹本丰
荣晓莹
李永刚
张元明
周晓兵
Du Fan;Yang Jungang;Guo Xing;Lu Yongxing;Tao Ye;Yin Benfeng;Rong Xiaoying;Li Yonggang;Zhang Yuanming;Zhou Xiaobing(College of Life Sciences,Shihezi University,Shihezi 832003,Xinjiang,China;Xinjiang Key Laboratory of Biodiversity Conservation and Application in Arid Lands/Xinjiang Field Scientific Observation Research Station of Tianshan Wild Fruit Forest Ecosystem,Yili Botanical Garden,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China;School of Resources and Environment,Henan Institute of Science and Technology,Xinxiang 453003,Henan,China)
出处
《中国沙漠》
北大核心
2025年第3期175-184,共10页
Journal of Desert Research
基金
国家自然科学基金项目(42377358)
天山英才计划项目(2022TSYCCX0001,2022TSYCLJ0058)。
关键词
藻结皮
颗粒态有机碳
矿物结合态有机碳
土壤理化性质
荒漠生态系统
cyanobacterial crust
particulate organic carbon
mineral-associated organic carbon
soil physicochemical characteristics
desert ecosystem
