利用微气象测定仪MINCER分析热害条件下的水稻冠层微气象特征

采用模型模拟水稻热害过程及其可能的产量损失是水稻耐高温研究的重要一环,但较精确地测定水稻冠层的微气象条件还存在诸多困难。采用最新研制的水稻冠层微气象测定仪Mincer实地测定法研究了水稻花期热害受害下的冠层微气象特征,并将相关数据与邻近国家基本气象观测站的数据比较,从而形成了水稻冠层、水稻田田面上部(距田面2倍株高,约1.9m)和空旷地(距地面1.5m)等的对比。结果表明,供试品种受到花期热害后,结实率降低4.0%,达到显著受害水平。在此条件下,日平均气温值由水稻田冠层、水稻田上部与空旷地相比依次升高,水稻冠层与水稻田上部的温度值一般分别比空旷地低2.05、0.92℃,且在连续高温的部分时段出现冠层温度的异常升高;相对湿度值反之,由冠层内部、水稻田上部与空旷地依次降低,水稻冠层与水稻田上部的相对湿度值分别比空旷地低高14.55%、5.97%(绝对值)。此外,高温天气下开花前后水稻田上部与冠层温湿度差的变化幅度都小于常温天气,且出现的时间段早于常温。这些结果,对设定水稻高温受害鉴定条件、模拟水稻高温受害过程均具有重要指导意义。

ANALYSIS ON CHARACTERIZING THE MICRO-METEOROLOGY OF RICE CANOPY BY MINCER AT FLOWERING STAGE UNDER HEAT-STRESSED SCENARIOS

Applying model to simulate the process of rice heat injury and its potential yield loss is a key part of the research on high temperature resistance of rice,but there exist some difficulties in measuring micrometeorology of rice canopy accurately.This study adopted MINCER,which is the latest newly development for rice canopy micrometeorological measurement,to determine the microclimate conditions in rice canopy during heat injury.Comparing the observation data with the meteorological data of the neighborhood national basic meteorological station,three groups of comparative data were sorted,such as date of rice canopy,date of upper rice field and date of open area.The date of upper rice field was detected at the height of 1.9 m,which is the twice plant height above the field,and the date of open area was observed at the height of 1.5 m.The experiment shows that the seed setting rate of tested cultivars was significantly reduced by 4 ％ after sufferring high temperature weather at flowering stage.The daily average temperature of rice canopy,upper rice field and open area were increased in turn,and the temperature of rice canopy and upper rice field were 2.05℃ and 0.92℃ lower than the open area.But during continuous high temperature period,the rice canopy temperature showed an abnormal increase periodically.Contrary to the case of temperature,relative humidity of rice canopy,upper rice field and open area were decreased in sequence,relative humidity of rice canopy and upper rice field were 14.55％ and 5.97％(absolute value) higher than open area.Under high temperature condition,the variation range of the difference between upper rice field and the rice canopy temperature was less than under normal weather,and great temperature difference between them appeared earlier than under normal weather condition.This was the same as the relative humidity.These results were of great significance to guide the research of the rice heat injury identification conditions and the simulation process of rice heat injury.