摘要
基于CASA模型估算云南省1982—2019年植被净初级生产力(NPP),分析其时空变化特征,并结合标准降水蒸散指数SPEI,探讨不同时间尺度干旱与NPP的关系.结果表明,随着SPEI积累程度增加,干旱频率大于30%的面积比例也在增加;遭受大规模干旱的年份,植被NPP相对较低,年均NPP与干旱影响范围整体上呈负相关关系,主要集中在滇中高原地区;当干旱面积比例从小于30%上升至30%~40%、40%~50%、50%以上时,NPP分别下降3.3%、4.5%、8.7%;12个月尺度的长期干旱对植被NPP的影响大于中短期干旱;整体上植被NPP对干旱的敏感期出现在5月份和10月份.但是,不同植被类型对干旱的敏感性响应存在差异,热带森林在6月份对于3个月尺度干旱最为敏感;在8月份对于12个月尺度干旱最为敏感,灌丛、草地、农业植被对3个月尺度干旱最为敏感,高山植被对6个月尺度干旱最为敏感.
Based on CASA model, net primary productivity(NPP) of vegetation was estimated from 1982 to2019 in Yunnan Province, and its spatiotemporal variation characteristics were analyzed. In combination with the standard precipitation evapotranspiration index(SPEI), the relationship between droughts and NPP at different time scales was discussed. The results show that as the SPEI accumulation increased in the study area, so did the proportion of areas with drought frequency greater than 30%. NPP is relatively low in the years with large-scale droughts. There was a negative correlation between average annual NPP and drought affected area, mainly concentrated in central Yunnan Plateau region. When the proportion of drought area increased from under 30% to30%-40%, 40%-50% and above 50%, NPP decreased by 3.3%, 4.5% and 8.7% respectively. Long-term drought on a 12-month scale had a greater impact on NPP than short and medium term drought. On the whole, the sensitive period of NPP to drought appeared in May and October, but the sensitivity responses of different vegetation types to drought were different. Tropical forests were most sensitive to three-month drought in June and to 12-month drought in August. Meanwhile, shrub, grassland and agricultural vegetation were the most sensitive to 3-month drought, while alpine vegetation was the most sensitive to 6-month drought.
作者
闫文波
何云玲
余岚
屈新星
YAN Wen-bo;HE Yun-ling;YU Lan;QU Xin-xing(School of Earth Sciences,Yunnan University,Kunming 650500,Yunnan,China)
出处
《云南大学学报（自然科学版）》
CAS
CSCD
北大核心
2021年第4期736-745,共10页
Journal of Yunnan University(Natural Sciences Edition)
基金
国家自然科学基金(41961044).
关键词
植被净初级生产力(NPP)
SPEI指数
CASA模型
敏感月
net primary productivity(NPP)
standardized precipitation evapotranspiration index(SPEI)
carnegie-ames-stanford approach(CASA)model
sensitive month
