摘要
为明确土壤养分含量及化学计量比对多种限制性养分添加的响应,分析土壤中速效养分与全量养分相关关系,以及土壤全量和速效化学计量特征的指示作用,阐明养分添加对荒漠草原土壤养分动态平衡关系的影响.以宁夏荒漠草原为研究对象,于2018年开始进行氮(N)和磷(P)养分添加控制试验,试验处理包括对照(CK)、N添加、P添加和NP共同添加这4个处理.结果表明:(1)养分添加第4年,土壤N含量显著增加;N添加显著增加土壤N∶P,P添加和NP共同添加显著增加土壤有机碳(SOC)含量.养分添加第3年和第4年,N添加显著提高土壤速效N∶P(AN∶AP);N添加和NP共同添加显著增加土壤铵态氮(NH+4-N)和硝态氮(NO-3-N)含量,而降低土壤速效C∶N(C∶AN);P添加和NP共同添加显著增加土壤全磷(TP)和速效磷(AP)含量,而降低土壤全量和速效N∶P、C∶P.(2)N添加和P添加对荒漠草原土壤NH+4-N、AP含量和土壤速效C∶N、AN∶AP的影响具有显著交互作用.(3)荒漠草原具有较为稳定的C∶N,N∶P主要受土壤P含量的限制,速效C∶P(C∶AP)和AN∶AP主要受土壤AP含量的限制.(4)N、P养分添加对土壤TN、SOC和无机氮的影响具有累积性效应,N添加缓解荒漠草原N限制,P添加和NP添加加剧荒漠草原N限制.土壤速效化学计量特征变异系数均大于土壤全量化学计量特征变异系数,荒漠草原土壤速效化学计量对N、P养分添加更敏感,可更好反映N、P养分添加对荒漠草原土壤生态化学计量的影响,更快速地指示土壤养分状况.
In order to discuss the response of soil nutrient content,stoichiometric ratio,and dynamic nutrient balance to the addition of multiple restrictive nutrients,the correlation between available nutrients and total nutrients in soil,as well as the indication of soil total and available stoichiometric characteristics,were studied in a desert grassland subjected to 4 years of nutrient addition treatments.The Ningxia desert grassland was used as the research object to carry out nitrogen(N)and phosphorus(P)addition experiments.The experiment included four treatments:control(CK),N addition[10 g·(m2·a)-1],P addition[10 g·(m2·a)-1],and NP co-addition(10 g·(m2·a)-1 N+10 g·(m2·a)-1 P).The results showed that:①in the fourth year of nutrient addition,soil total nitrogen(TN)content was significantly increased.The N∶P ratio was significantly increased by N addition,and soil organic carbon(SOC)content was significantly increased by P addition and NP co-addition.In the third and fourth years of nutrient addition,the soil available N∶P ratio(AN∶AP)was significantly increased by N addition;N addition and NP co-addition significantly increased the content of ammonium nitrogen(NH4+-N)and nitrate nitrogen(NO3--N)but significantly reduced the soil available C∶N ratio.P addition and NP co-addition significantly increased total phosphorus(TP)and soil available phosphorus(AP),whereas it significantly reduced the soil total and available C∶P and N∶P ratios.②The interaction between N addition and P addition had a combined effect on NH4+-N,AP,available C∶N,and AN∶AP ratio of desert grassland.③The soil C∶N ratio was relatively stable in desert grassland,soil N∶P ratio was mainly limited by soil TP content,and the soil available C∶P and AN∶AP ratios were mainly limited by soil AP content.④There were cumulative effects of N and P additions on soil N,SOC,and inorganic nitrogen.N limitation in desert grassland was alleviated by N addition,whereas it was aggravated by P addition and NP co-addition.The variation coefficients of soil available stoichiometric characteristics were higher than that of soil total stoichiometric characteristics.Soil available stoichiometry was more sensitive to N and P addition than soil total stoichiometry in desert grassland,which could better reflect the effects of N and P addition on soil ecological stoichiometry and as a rapid indicator of soil nutrient status in desert grassland.
作者
刘姝萱
安慧
张馨文
邢彬彬
文志林
王波
LIU Shu-xuan;AN Hui;ZHANG Xin-wen;XING Bin-bin;WEN Zhi-lin;WANG Bo(Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwestern China,Key Laboratory of Restoration and Reconstruction of Degraded Ecosystems in Northwestern China of Ministry of Education,School of Ecology and Environment,Ningxia University,Yinchuan 750021,China;Grassland Experiment Station of Yanchi,Temperate Grassland Ecosystem Observation and Experiment Station in Agro-Pastoral Ecotone of Ningxia,Yanchi 751506,China;Grassland Station of Ningxia,Yinchuan 750004,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2023年第5期2724-2734,共11页
Environmental Science
基金
国家自然科学基金项目(31960244)
宁夏自然科学基金项目(2022AAC02010)
宁夏回族自治区西部一流学科项目(NXYLXK2017B06)。
关键词
荒漠草原
养分添加
土壤养分
生态化学计量
desert grassland
nutrient addition
soil nutrient
ecological stoichiometry
作者简介
刘姝萱(1998-),女,硕士研究生,主要研究方向为全球变化生态学,E-mail:lsx19980123@163.com;通信作者:安慧,E-mail:anhui08@163.com。
