摘要
利用涡度相关技术(Eddy covariance technique)、小型蒸渗仪(Mini—lysimeter)和波文比-能量平衡法(BREB)对2005年和2006年夏季(7—8月份)青藏高原海北高寒草甸生态系统的昼间蒸散(E)变化进行了对比观测研究。在观测期间,存在能量不闭合现象,涡度相关系统测定的湍流通量相当于有效能量的73%。3种不同方法测定的蒸散量之间具有较好的相关性,涡度相关系统与小型蒸渗仪测定的蒸散量相关系数达0.96,与波文比法的结果相关系数为0.95。然而,波文比法计算的蒸散量最大,比涡度相关系统的观测值高43%;小型蒸渗仪法的测定值次之,比涡度相关法的观测值高19%;涡度相关法测算的蒸散值最小。研究结果表明,利用涡度相关技术测定该高寒草甸生态系统的潜热通量,可能会过小评价该生态系统的蒸散量。
The daytime evapotranspiration (E) was measured using the eddy covariance (EC) technique, the minilysimeter method, and the Bowen ratio-energy balance (BREB) method, in an alpine meadow ecosystem on the Qinghai-Tibetan plateau during the growing season of 2005 and 2006 ( Jul. - Aug. ). The energy imbalance with a slope of 0.73 was found in this study. Results showed a significant correlation between the E measured with the three methods, with the correlation coefficient of 0.96 between the EC technique and the mini-lysimeter method, and 0.95 between the EC technique and the BREB method. However, the value of E measured by the BREB was the largest, which was 43% higher than that by the EC ; whilst the E measured with the mini-lysimeter had the medium value, which was 19% higher than that by the EC. The results suggest that the E may be underestimated using the EC in this alpine meadow on the Qinghai-Tibet Plateau.
出处
《生态学报》
CAS
CSCD
北大核心
2008年第1期202-211,共10页
Acta Ecologica Sinica
基金
中国科学院“百人计划”资助项目(0429091211)
日本环境厅全球环境研究基金(S-1)
国家自然科学基金资助项目(30770419)~~
关键词
蒸散
波文比
涡度相关技术
小型蒸渗仪
高寒草甸
evapotranspiration
bowen-ratio
eddy covariance technique
mini-lysimeter
alpine meadow