西藏原始墨脱冷杉林微气候特征  

Microclimate Characteristics of the Primitive Abies Delavayi var.Motuoensis in Medog,Xizang

作　　者：景梦洁 赵旺林 刘新圣 张林[2,3] JING Mengjie;ZHAO Wangin;LIU Xinsheng;ZHANG Lin(School of Geography and Tourism of Anhui Normal University,Wuhu 241002,China;Institute of Tibetan Plateau Research Chinese Academy of Sciences,Beijing 100101,China;Key Laboratory of Biological Resources and Biosafety,Institute of Plateau Biology of Xizang Autonomous Region,Lhasa 850000,China)

机构地区：[1]安徽师范大学地理与旅游学院,安徽芜湖241002 [2]中国科学院青藏高原研究所,北京100101 [3]西藏自治区高原生物研究所生物资源与生物安全重点实验室,西藏拉萨850000

出　　处：《高原科学研究》2024年第1期18-28,共11页Plateau Science Research

基　　金：第二次青藏高原综合科学考察项目(2019QZKK0301);西藏自治区自然科学基金项目(XZ202301ZR0027G);安徽师范大学大学生创新创业训练计划项目(202310370047).

摘　　要：受印度洋暖湿气流的影响,墨脱高海拔地带分布了大量的以墨脱冷杉(Abies delavayi var.motuoensis)为主的原始湿润森林,开展森林微气候研究能够为高寒生态脆弱区的植被保护和生态建设提供理论依据。文章基于2020年墨脱喜荣沟(海拔2700 m)原始冷杉林林内外的微气候监测数据,对比分析了林内与林外温度、湿度及不同深度土壤温度的季节变化特征,探讨了植物的生长季长度及生长季期间的低温事件发生情况。结果表明:(1)气温日变化特征显示,林内日间气温比林外低0.2∼2.7℃,森林表现出降温作用;除夏季外,其他季节林内夜间气温比林外均高0.2∼1.2℃,森林表现出保温作用;从季节变化看,林内外气温最高值出现在8月,最低值在1月,但林内气温较林外更加稳定;(2)该区域相对湿度较高(>80%),且在不同季节均表现为林内>林外;(3)除冬季外,土壤温度日变化总体呈现与气温类似的日动态,但土壤温度明显滞后约2∼3 h,林内土壤温度总体低于林外;春夏两季不同深度的土壤温度表现为5cm>10cm>20cm,而秋冬两季越靠近地表土壤温度则越低;(4)基于气温定义的生长季长度为208天,明显低于基于土壤温度定义的生长季长度(256∼268天);(5)2020年,冷杉林内低温事件发生的频率、强度及持续时间分别为1 d、-0.03℃和1 h,分别比林外少(低)了6 d、0.86℃和7 h。上述研究表明,原始墨脱冷杉林具有明显的保温和缓冲低温事件影响的作用,因此在未来亚高山天然林的保护和管理中应加强对森林微气候的观测和研究,不断提升天然林对气候变化的潜在应对能力。Under the influence of the warm and humid airflow of the Indian monsoon,a large number of primitive moist forests dominated by Abies delavayi var.motuoensis are distributed at higher altitudes in Medog,southeast Xizang Autonomous Region,and the study of forest microclimate in this area can provide a theoretical basis for vegetation protection in alpine ecological fragile zones.In this study,based on the microclimate monitoring data inside and outside the fir forest at Xirong Gully(2700 ma.s.l)in Medog in 2020,we compared the seasonal char-acteristics of air temperature,humidity and soil temperature at different depths inside and outside the forest,and further explored the growing season length and the occurrence of low-temperature events during the growing sea-son based on the air and soil temperature.The results showed that:(1)at the daily scale,the air temperature in-side the forest was 0.2~2.7℃lower than that outside the forest at daytime,and the forest showed a cooling effect.The air temperature inside the forest was 0.2~1.2℃higher than that outside the forest at nighttime except in sum-mer,which indicated that the forest reflected an insulating effect.In terms of seasonal changes,the highest air temperature appeared in August both inside and outside the forest,and the lowest occurred in January,and the air temperature inside the forest was more stable than outside.(2)The relative humidity at different seasons showed a higher value inside the forest than outside.(3)The daily changes in soil temperatures showed similar dynamics with air temperature except for winter,and lagged behind by about 2~3h.The soil temperature at differ-ent depths in spring and summer showed a sequence of 5 cm>10 cm>20 cm,while it reversed in autumn and win-ter.(4)The growing season length based on air temperature was 208 days,while that based on soil temperature was significantly longer(256~268 days).(5)During 2020,the frequency,intensity and duration of low-tempera-ture events in fir forest were 1 day,-0.03°C and 1 h,respectivel

关 键 词：低温事件 气温 土壤温度 墨脱冷杉林 生长季长度 

分 类 号：S714[农业科学—林学]