NFT设施栽培黄瓜营养液溶氧量的研究

Oxygen content of nutrient solution in NFT system for cucumber culture

1990年5、6月对杭州玻璃温室内NFT设施栽培黄瓜的营养液进行了溶氧量的测定。结果表明,营养液氧量以进液口一端为高18.67—8.85mg·1^(-1)),以排液口一端为低(7.58—8.10mg·1^(-1);溶氧饱和度分别为90.3—98.2％与81.5—84.9％。溶氧量与液温呈显著负相关(r=-0.831~*)。晴天15:00液温最高,溶氧量低,而进液口与排液口之间溶氧消减量最大。在相等的液温和光强时,下午和上半夜的溶氧消减量比上午的大,而溶氧量则相反。当水溶液流过不种植植物的NFT栽培床时,排液口溶氧量高于进液口,表现“富氧”现象。

Oxygen content of nutrient solution in NFT system for cucumber culture in glasshouse was measured on sunny days of May and June. 1990 in Hangzhou.Oxygen content was 8.67-8.85 mg·l^(-1) with a saturation of 90.3-98.2% at the inlet of NFT bed.and 7.58-9.10mg·l^(-1) with a saturation of 81.5-84.9% at the outlet.Oxygen content was negatively correlated with solution temperature (r=-0.831*).The lowest content of oxygen on solution was found when the solution temperature went up to the highest at 15:00 in sunny day indicating the highest exhausting of oxygen at this time.The oxygen content at same light intensity or solution temperature was lower during 15:00 to 21:00 than that during 6:00 to 22:00,while oxygen decreasing amount was the opposite.The oxygen content increased when water flowed through the unrplanted NFT bed.