摘要
黄土高原生态系统是一个巨大的有机碳汇潜力库,也是响应气候变化敏感的生态脆弱区。水资源供需不平衡引发的不同干旱严重威胁了区域生态系统碳汇功能。不同类型干旱对黄土高原生态系统年总初级生产力(AGPP)影响的解析仍然不足。采用黄土高原定位观测站点的AGPP数据、遥感估算的AGPP(2004—2020年)和气候要素数据集,解析了黄土高原生态系统AGPP时空动态变化,探讨了干燥度指数(AI)、大气饱和水汽压差(VPD)和土壤水分(SM)的时空动态格局及其与AGPP年际变异的响应模式。结果表明:近20年AGPP总体增加了38.30%,主要植被恢复区的AGPP增加了56.45%,并且呈现出AGPP均值越大的区域增加速率越快的空间分异规律;SM和AI具有显著的增加趋势,VPD不具有显著的趋势性变化;AGPP与SM和AI的年际变异具有显著的线性正相关关系,而与VPD年际变异的相关性不显著。AGPP与SM、AI和VPD的年际动态响应关系表明,在主要植被恢复区和整体区域水文和气象干旱主导了区域生态系统AGPP的年际变异,而大气干旱的影响不明显。研究结果将为区域生态环境建设和提升生态碳汇功能提供科学依据。
The Loess Plateau is a vast potential organic carbon pool and is also an ecologically fragile region,exhibiting sensitivity to climate change.Various types of droughts,stemming from the imbalance between water supply and demand,will have a profound and far⁃reaching impact on the steady enhancement of ecosystem carbon sinks.However,currently,research on the impacts of various types of droughts on the annual gross primary productivity(AGPP)in the Loess Plateau is still in its infancy.In this study,AGPP,soil moisture(SM),and climatic factors were used to analyze the temporal dynamics of AGPP.Additionally,the interannual variations of AGPP in relation to SM,aridity index(AI),and vapor pressure deficit(VPD)were explored for the period from 2004 to 2020 in the Loess Plateau.The results demonstrate that over the past 20 years,the overall growth rate of AGPP has reached 38.30%,and the AGPP in the major vegetation restoration area has increased by 56.45%.The temporal trends of AI and SM exhibited a remarkable inclination to ascend,whereas the temporal trends of VPD did not display any significant directional alterations.The temporal correlation pattern between AGPP and SM,AI,as well as VPD suggested that soil drought preponderantly governed the interannual variation of AGPP,while the influence of atmospheric drought remained relatively inconspicuous in the Loess Plateau.The research outcomes will supply a theoretical and practical foundation for the construction of the regional ecological environment and the enhancement of the ecological carbon sink.
作者
宋仕燕
祁旭阳
田露荷
陆欣雨
王颖颖
吴侗昱
张添佑
SONG Shiyan;QI Xuyang;TIAN Luhe;LU Xinyu;WANG Yingying;WU Tongyu;ZHANG Tianyou(College of Grassland Agriculture,Northwest Agriculture and Forest University University,Yangling 712100,China)
出处
《生态学报》
北大核心
2025年第10期4916-4926,共11页
Acta Ecologica Sinica
基金
陕西省重点研发计划(2024SF-YBXM-555)
国家自然科学基金项目(32201344)
中国博士后科学基金(2023M742858)。
关键词
年总初级生产力
土壤水分
大气饱和水汽压差
干旱
黄土高原
annual gross primary productivity
soil moisture
vapor pressure deficit
drought
the Loess Plateau
