日光温室内光合有效辐射基本特征分析

基于日光温室内观测的辐射资料,对光合有效辐射特征及对作物的影响进行研究分析.结果表明:温室内日光合有效辐射累计值与日水面蒸发量呈较好的线性关系,相关系数为0.7974;日光温室内作物光合速率随光合有效辐射上升到一定程度后,将不随光合有效辐射的增加而增加;叶片细胞液质量分数与光合有效辐射日变化均呈单峰型曲线,叶片细胞液质量分数相对于光合有效辐射有明显的滞后现象;日光温室内冬、春季晴天及阴天的太阳总辐射Q和光合有效辐射(PAR)日变化均为单峰型曲线,晴天和阴天太阳总辐射和光合有效辐射日变化趋势一致,阴天比晴天小;2007年秋季和2008年春季日光温室内小型西瓜的光合有效辐射利用率分别为6.38%和6.31%,高于大田作物的光合有效辐射利用率值.

Photosynthetic Active Radiation (PAR) in Greenhouse

The characteristics and effects of photosynthetic active radiation (PAR) on crops were analyzed on the basis of the observed radiation data from greenhouse. The results showed that a linear relationship between PAR and water surface evaporation exists, with the correlation coefficient of 0.7974. The photosynthesis rate (Pn) increases with the PAR increasing, but when the PAR reached a certain number, the photosynthesis rate stopped increasing. The cell sap concentration of leaf (CSC) shows a single peak curve with the PAR, but has a certain delay phenomenon relative to the PAR. The daily variation trends of the total solar radiation (Q) and PAR presents a single peak curve in sunny day or overcast day during winter or spring, Furthermore, the values in sunny day are higher than in overcast day. The utilization ratio of PAR for mini-watermelon in the autumn of 2007 and the spring of 2008 are 6.38% and 6.31% respectively, above the result of field crop.