摘要
气候变化对草地碳循环的影响日益严峻,研究运用本地参数化后的CENTURY模型和1989—2018年甘肃省77个站点的气象观测数据,选用生产指标净生态系统生产力(NEP)和生态指标土壤有机碳(SOC)为主要研究对象,检验模型适用性、利用统计分析方法和ArcGIS软件分析30年气候数据时空分布格局和气候变化对草地碳循环的影响机制。同时根据IPCC第五次评估报告对气候变化的预测设计了3种气候情境,预估未来气候变化条件下,NEP和SOC的时空变化特征,并与实际情景进行对比分析。结果表明,过去30年年际NEP和SOC整体呈现波动下降的趋势,NEP以每年14.23 gC·m^(-2)·a^(-1)的速度减小,1989—2018年的NEP均大于零,表现为碳汇;SOC以每年55.41 gC·m^(-2)的速度减小,正在逐年流失。温度、降水是影响NEP和SOC的主要因素,NEP与温度显著正相关,与降水有较弱的正相关,SOC与温度显著负相关,与降水有较弱的负相关。在未来气候情景中,气温升高和降水波动增大是导致NEP和SOC变化的主要原因,且CO_(2)浓度加倍时,单独的气温升高会导致NEP显著增加,SOC显著降低;单独的降水波动增大对NEP和SOC的影响不大。在甘肃北方干旱地区,降水成为主要限制因子。
The impact of climate change on grassland carbon cycle is becoming more and more serious,based on local parameterized CENTURY model and meteorological observation data from 77 station in Gansu Province from 1989 to 2018,net ecosystem productivity(NEP)and ecological index soil organic carbon(SOC)were selected as the main research object,the applicability of the model was verified,and the spatial and temporal distribution pattern of climate data in 30 years and influence mechanism of climate change on grassland carbon cycle were analyzed using statistical analysis method and ArcGIS software.At the same time,three climate scenarios were designed according to the climate change prediction in the fifth assessment report of IPCC,to predict the spatial-temporal variation characteristics of NEP and SOC under the future climate change conditions,and to make comparative analysis with the actual scenarios.The result show that the annual NEP and SOC have fluctuated and decreased in the past 30 years.The NEP decreases at the rate of 14.23 gC·m^(-2)·a^(-1)per year,and the NEP from 1989 to 2018 is all greater than zero,which represents the carbon sink;SOC is decreasing at the rate of 55.41 gC·m-2 per year and is being lost year by year.Temperature and precipitation are the main factors affecting NEP and SOC,NEP is significantly positively correlated with temperature and weakly positively correlated with precipitation.SOC is significantly negatively correlated with temperature and weakly negatively correlated with precipitation.In the future climate scenario,the increase of temperature and precipitation fluctuation are the main reasons for the change of NEP and SOC,and when the CO2 concentration doubles,the increase of temperature along will lead to a significant increase in NEP and a significant decrease in SOC,while the increase of precipitation fluctuation along will have little impact on NEP and SOC,precipitation is the main limiting factor in the northern arid area of Gansu Province.
作者
李晓娟
张美玲
曹瑞红
贾晓楠
朱美婷
罗上学
聂雅梅
Li Xiaojuan;Zhang Meiling;Cao Ruihong;Jia Xiaonan;Zhu Meiting;Luo Shangxue;Nie Yamei(College of science,Gansu Agricultural University,Lanzhou 730070,China)
出处
《国土与自然资源研究》
2023年第5期79-83,共5页
Territory & Natural Resources Study
基金
甘肃省重点研发计划(21YF5WA096)
甘肃省自然科学基金项目(1606RJZA077,1308RJZA262)
甘肃农业大学青年导师扶持基金(GUO-QDFC-2019-03)。
