不同时间尺度下黄土塬区19年生苹果树干液流速率与环境因子的关系  

The Relationship Between Sap Flow Velocity and Environmental Factors of the 19 a Apple Trees on the Loess Plateau at Different Time Scales

作　　者：张静[1] 王力[1] 韩雪[1] 张林森[2] 

机构地区：[1]西北农林科技大学资源环境学院/黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [2]西北农林科技大学园艺学院,陕西杨凌712100

出　　处：《中国农业科学》2016年第13期2583-2592,共10页Scientia Agricultura Sinica

基　　金：国家自然科学基金(41390463;41571218);中央高校基本科研业务费(2452015120)

摘　　要：【目的】以黄土高原沟壑区的典型代表长武塬为研究区,通过环境因子估算19年生苹果树耗水速率在不同时间尺度上的可行性,以期为黄土塬区有限水资源条件下苹果发展的科学布局、合理制定果园管理措施、增强其生产能力提供理论依据。【方法】选取黄土塬区长武县19年生苹果林生态系统为研究对象,应用热扩散式茎流计(TDP)于2014年5—9月对苹果林内8株标准果树树干液流速率进行连续测定,并通过数据采集器CR1000(Campbell Scientific,UN)对数据进行采集分析,用位于距样地50 m处的自动气象观测站连续监测获取气象数据;分析不同时间尺度下19年生苹果树干液流速率与环境因子的关系,建立不同时间尺度下树干液流速率与环境因子的关系模型。【结果】小时尺度下,苹果树干液流速率与水汽压差相关关系最密切,且与太阳辐射、风速和地表温度均呈极显著相关关系,树干液流速率曲线呈明显的单峰曲线,逐步回归方程为:v=-11.683+2.3VPD+0.009Rs+0.55Ts+0.880Ws,相关系数为0.779。日尺度下,只有地表温度、水汽压差与苹果树干液流速率显著相关。逐步回归方程为:v=1.637+0.404Ts-3.097VPD,相关系数为0.771。月尺度下,19年生苹果树干液流速率整体表现为8月>7月>6月>9月>5月,进入逐步回归方程的仅有地表温度,逐步回归方程为:v=-3.524+0.509Ts,相关系数为0.981。时间尺度越大,与苹果树干液流速率相关的环境因子越少,但地表温度始终都是其主导因子,且相关系数随着时间尺度的增大而增大;风速只在小时尺度下与树干液流速率极显著相关。水汽压差在小时尺度下与树干液流速率极显著正相关,在日尺度下与树干液流速率极显著负相关;太阳辐射在3种尺度下与树干液流速率的相关关系不明确。3种尺度下的逐步回归方程,以月尺度下的相关系数最大。【结论】在较大的时间尺度上,通过对少量[ Objective ] The Changwu Tableland was taken as a study area in consideration of its typical representative of the Loess Plateau. The purposes of the study were to estimate water consumption rate of 19 a apple trees at different time scales by environmental factors, and provide a theoretical basis for the scientific distribution, sustainable management and production capacity of apple trees. [Method] Thermal dissipation probe （TDP） was used to measure sap flow velocity of 8 standard 19 a apple trees on the Changwu Tableland located on the Loess Plateau from May to September, 2014, the data collector CR1000 （Campbell Scientific, UN） was used to collect and analyze the data, and the meteorological data were monitored continuously by automatic weather station 50 m away from the plot. The characteristics of sap flow were analyzed, and the relationship model between the rate of sap flow rate and environmental factors at different time scales was established. [Result] The most close correlations between the sap flow velocity of the 19 a apple tree and various environmental factors at the hour scale was vapor pressure difference （VPD）. Radiation （Rs）, wind velocity （Ws） and soil temperature （Ts） also showed significant correlations with the sap flow. The sap flow curve had a single peak. The empirical model for the hour scale was： v=-I 1.683＋2.3VPD＋0.009Rs＋0.55Ts＋0.880Ws. At the day scale, Ts and VPD were significantly correlated with the sap flow velocity. The empirical model for the day scale was： v=l.637＋0.404Ts- 3.097VPD. The sap flow velocity showed an order of August〉 July 〉 June 〉 September〉 May. Only Ts showed a correlation with the sap flow velocity. The empirical model for the month scale was： v=-3.524＋0.509Ts. With the increasing time scales, the number of environmental factors associated with the sap flow velocity was gradually reduced, but Ts was the dominant factor at every scale and the correlation coefficients were gradually increased. Wind velocity （W

关 键 词：苹果 热扩散探针法 液流速率 时间尺度 环境因子 

分 类 号：S661.1[农业科学—果树学]