摘要
以盆栽玉米为试材、称重法为基准，验证了GREENSPAN茎流法测量作物蒸腑量的可行性。茎流法与称重法两者测值的绝对误差为0．20～4．56g／（株·h），相对误差为2．03％～10．42％。表明茎流计所测得的玉米茎流速率可准确的表示作物蒸腾速率。以此为基础，探讨了不同天气下GREENSAPPAN茎流法实测玉米茎流的日变化规律：白天玉米茎流随太阳辐射及天气变化星规律性变化，晚间有较细微而稳定的茎流。晴好天气，玉米茎流的日变化星单峰曲线，多云或阴天天气，为不对称的“M”型，且茎流的启动时间存在一个受天气和太阳辐射变化共同影响的临界值。灰色关联度分析表明，晴好天气下，太阳辐射是影响蒸腾速率的主要因素；多云或多云转晴天气下，气温和相对温度成为影响蒸腾速率的主要因素，太阳辐射的作用相对降低。
The accuracy and the validation of maize transpiration measured with sap flow by GREENSPAN technique were evaluated through pot experiment and weighting method. The absolute and the relative errors of measured values by GREENSPAN technique were 0. 20-4.56 g/h per plant and 2.03%- 10.42% separately compared with values through weighing methods which showed that the transpiration measured with the Sap Flow can exactly express the transpiration of mazie. Based on this,the diurnal variation of sap flow under different weather conditions was studied which showed that the change of maize transpiration has strong correlation with solar radiation and different weather conditions in day time and there was steady and minuteness sap flow in night time. Daily variations of sap-flow showed slngle-peak curve in fine days and dissymmetrical＂M＂ type in cloudy days ,and there existed a start up time of sap flow which decided by the weather and solar radiation. The grey correlated analysis showed that the main meteorological factors affected on transpiration of maize were solar radiation in fine days. The air temperature and relative humidity were the main factors and the effects of solar radiation on transpiration reduced in cloudy days.
出处
《水土保持研究》
CSCD
北大核心
2006年第2期134-137,共4页
Research of Soil and Water Conservation
基金
山东省教委项目(J02L01)资助
关键词
茎流计
玉米
蒸腾速率
气象因子
日变化
sap-flow gauge
maize
transpiration rate
weather factors
daily change
