大棚甜瓜蒸腾规律及其影响因子  

The critical factors of transpiration on muskmelon in plastic greenhouse

作　　者：张大龙[1] 常毅博[1] 李建明[1] 张中典[1] 潘铜华[1] 杜清洁 郑刚[1] 

机构地区：[1]西北农林科技大学园艺学院,杨凌712100

出　　处：《生态学报》2014年第4期953-962,共10页Acta Ecologica Sinica

基　　金：国家"十二五"863计划资助项目(2011AA100504);国家"十二五"科技支撑计划资助项目(2011BAD29B01)

摘　　要：研究大棚甜瓜的蒸腾规律和影响因子,可以为大棚甜瓜水分优化管理提供理论依据。利用大棚盆栽试验,设定了4个水分梯度,定量分析了大棚甜瓜蒸腾规律及蒸腾量与植株生理特性、气象环境因子、土壤水分含量的关系。结果表明:(1)各水分处理条件下甜瓜蒸腾强度日变化曲线均呈"双峰型",有明显的"午休"现象。(2)甜瓜生理需水系数与叶面积指数、有效积温关系显著,分别呈线性和抛物线函数关系。(3)甜瓜全生育期累计蒸腾量呈现出"慢—快—慢"的变化规律,可以用Logistic函数进行模拟。(4)甜瓜叶面积指数、日平均空气温度、日平均空气相对湿度、日太阳辐射累积、土壤相对含水量均与单株日蒸腾量呈显著性相关关系;甜瓜叶面积指数对蒸腾的综合作用最大,是决策变量;土壤水分含量是限制变量,主要通过对其他因子的影响间接作用于蒸腾。(5)气象环境因子对甜瓜蒸腾量的影响力很大程度上取决于土壤水分含量;气象环境因子与蒸腾量的相关性随土壤水分含量的增大而增大,在土壤相对含水量为70%—80%范围内达到最高值,当土壤含水量接近田间持水量时,与各因子的相关系数逐渐下降。(6)甜瓜水分胁迫指数与土壤相对有效含水量关系显著,二者呈现线性关系。Although there is a rich history of studies of transpiration, a full description of the mechanisms that control this process still eludes us. This lack is related to the fact that control of this process is distributed over a large range of scales from atmospheric turbulence to the regulation of ion transporter in the membranes of cells. The aim of this study was to determine the actual relationship between muskmelon transpiration and multiple environmental and physiological factors under greenhouse condition. Pot experiments were conducted in a plastic greenhouse and physiological and ecological parameters were periodically measured as well as vegetative development. It is possible to draw some firm conclusions： （1） The diurnal course of muskmelon transpiration appeared as double-peak curve, with the peaks respectively appearing at 12：00 and 16：00; The double-peak curve showed gentle change tendency under water stress condition and acute fluctuation under sufficient water condition.（2）The physiological water requirement coefficients （K, ratio of crop transpiration to atmospheric evaporation） was characteristic index of internal biological control of transpiration, variation of K during whole growth period appeared as a quadratic function; There was a strong relationship between K and leaf area index （LAI）, effective accumulated temperature （TU） with high coefficients of determination（R2） of 0.941 and 0.909, respectively; The relationship between K and the two variables were explained with a linear function（K=0.439LAI＋0.093） and exponential function（K=-5×10TU2＋0.006TU - 0.014）.（3）The accumulative transpiration of muskmelon during growth period presented ＂S＂ dynamic course feasible for the logistic function to simulate with the independent variable of days（t） after transplanting[ET=70.188/（1＋63.553e-0.106t）, R2=0.997].（4）Significant correlation was found between muskmelon daily transpiration and leaf area index （LAI）、daily average temperature �

关 键 词：甜瓜 蒸腾作用 生理需水系数 通径分析 环境因子 土壤水分 

分 类 号：S652[农业科学—果树学]