干旱绿洲区微喷灰枣全年液流研究

Change in Intra-annual Sap Flow in Ziziphus Jujube in Arid Oasis under Micro-sprinkler Irrigation

【目的】探究枣树在生育期和休眠期茎流速率的变化规律及其与气象因子的关系,了解枣树各时期的耗水规律,为枣树的灌溉指导提供科学依据。【方法】通过针式茎流计对微喷灌下枣树的茎流速率进行全年连续监测,分析枣树在生育期(4月15日—10月14日)和休眠期(10月15日—翌年4月14日)的耗水量。【结果】生育期太阳辐射对灰枣茎流速率影响最为显著,各阶段相关系数R;=0.924、R;=0.939、R;=0.943和R;=0.915;休眠期则是空气湿度对灰枣茎流速率影响最为显著,各阶段相关系数R;=0.699、R;=0.923、R;=0.841、R;=0.918和R;=0.618。生育期和休眠期枣树日间最大茎流活动时长分别为14 h和9 h,且茎流在夜间的变化规律存在明显差异。生育期茎流速率高值区间在12:00—15:30,而休眠期茎流速率随着休眠的各时期发生偏移,C1阶段和C2阶段茎流速率的高值区间在03:00—06:00,C4阶段和C5阶段在07:00—10:00。生育期内各时期的耗水情况D3>D4>D2>D1;休眠期C1>C5>C3>C2>C4。【结论】枣树茎流全年的耗水量为3 994.03 L,休眠期为777.30 L,占比全年总耗水量的19.46%,枣树的休眠期长达183 d,休眠期的耗水对枣树的生长发育意义重大。

【Objective】Sap flow in stems is an approximation of transpiration.It changes with the environment and can be used to help irrigation management.The purpose of this paper is to investigate the intra-annual change in sap flow in the stems of jujube grown in an arid oasis in Xinjiang province,China.【Method】The jujube was irrigated by micro sprinkler irrigation;the sap flow was measured continuously using a needle-type stem flow meter for one year,from which we analyzed the change in water consumption of the jujube during its active growth and dormant periods.【Result】(1)Solar radiation affected the sap flow most and their correlation in the four active growth periods was R;=0.924,R;=0.939,R;=0.943 and R;=0.915,respectively.In winter when the crop stopped growing,air humidity affected the sap flow more and their correlation coefficient in the five growth periods was R;=0.699,R;=0.923,R;=0.841,R;=0.918 and R;=0.618,respectively.(2)During the active growing and dormant periods,the durations in which the sap flow was detectable using the meter was 14 h and 9 h,respectively.(3)During the active growth seasons,the sap flow peaked from 12:00 to 15:30 pm,while during dormancy it maximized from03:00 am to 06:00 am in the first two seasons and from 07:00 am to 10:00am in the last two seasons.(4)The water consumption during the active growth seasons was ranked in the order of D3>D4>D2>D1,while in dormancy the rank was C1>C5>C3>C2>C4.【Conclusion】The annual water consumption of the jujube was approximately 3 994.03 L,in which the consumption during the dormancy,which lasted for 183 days,was 777.30 L,accounting for 19.46%of the total water consumption of the tree.