南京林业大学学报（自然科学版）2016，Vol.40Issue(4)：89-94,6.DOI:10.3969/j.issn.1000-2006.2016.04.014
确定P-V曲线中质壁分离点的方法比较
Comparison of different methods for determining the turgor loss point in pressure-volume curves
摘要
Abstract
Water potential at turgor loss point (Ψtlp ) and relative water content at turgor loss point ( CRW,tlp ) have been considered important measurements of the drought tolerance of trees. This study comparedΨtlp and CRW,tlp by two types of P⁃V curves ( typeⅠ:Ψ versus C-1RW;typeⅡ:Ψ-1 versus 1-CRW ) and with three common calculation methods ( mathe⁃matical method, graphical method, and PV computer program) in typeⅡfor major tree species in the eastern mountain region of Northeast China. The results showed that average values ofΨtlp and CRW,tlp of eight species calculated from typeⅠwere 0.20 MPa and 3.17% higher than those calculated from typeⅡ. Especially parameters for the coniferous species Larix gmelinii and Pinus koraiensis were more significantly affected by two types of transformations than those of the broad⁃leaved species. In addition, the difference among species changed with different types of transformations. Ψtlp and CRW,tlp calculated by three methods for the same species were similar except thatΨtlp for Ulmus japonica calculated by the computer program was significantly higher than the value calculated by the mathematical method (P<0.05). The deter⁃mination coefficients (R2) between values of Ψtlp or CRW,tlp calculated by the three methods were in the range of 0.63-0�90 ( P<0.01) , and the values of R2 of the mathematical method and graphical method were the highest. Compared with the typeⅠcurve, the shape of typeⅡ P⁃V curve had the advantages of being smooth and the obvious boundary be⁃tween the curve part and the straight portion, making the turgor loss point easily detectable via plots of the data. Mean⁃while, the graphical method had the advantage of easily applied, which can make it being used widely in the future.关键词
P-V曲线/质壁分离渗透势/质壁分离相对含水量/质壁分离点确定方法Key words
pressure-volume curves/water potential at turgor loss point/relative water content at turgor loss point/meth-ods for determining the turgor loss point分类
农业科技引用本文复制引用
段瑞兵,孙慧珍..确定P-V曲线中质壁分离点的方法比较[J].南京林业大学学报（自然科学版）,2016,40(4):89-94,6.基金项目
国家自然科学基金项目（31300507）；“十二五”国家科技支撑计划 （）
