基质在热带兰栽培过程中的养分释放研究

采用PT法探究几种常见热带兰栽培基质有效氮、磷、钾释放及pH变化情况。结果表明:整个试验阶段所有处理基质pH变化在5.24～6.88,适合大多数花卉生长,水苔受外界环境影响最大,有着较大的pH变化,不适宜热带兰长期栽培。各基质的养分释放并不是按一定规律来进行,混合基质养分释放量低于纯基质,混合基质可以避免纯基质养分释放量大的弊端。NH4+-N的释放遵循类似"U"型曲线变化,火山石与松树皮混合有利于NO3--N的释放。前60d内,A与B处理磷的释放变化较大,60d后磷含量表现为下降变化,直至趋于平缓,不过混合基质整体磷含量水平较低。A与B处理的钾释放量分别在第15和45天降至平缓释放水平,以后一直维持在该平缓水平上释放钾。

The Matrix's Nutrient Release in Tropical Orchid Cultivation

Pour-Through method was used to explore that pH changed and available nitrogen,phosphorus and potassium released in cultivation matrix of tropical orchid.The results showed that pH of all treatments changed from 5.24 to 6.88 during the trial,and that was suitable for most flowers growing.On account of the external environment,sphagnum had great changes about pH which was not suitable for tropical orchid in long-term cultivation.The matrix of nutrient release was not according to certain rules.Mixed matrix had lower nutrient release than pure matrix,which were used to avoid the abuse that pure matrix’s higher nutrient release than mixed matrix.The laws of release about NH4+-N in all treatments followed a similar ’U’ curve.Volcanic rock mixed pine bark was advantageous to release of NO3——N.Within the first 60 days,there were major changes about available phosphorus in A and B treatments.After 60 days,the contents of phosphorus in A and B decreased until gentle trend.But the releases of phosphorus were low in all mixed matrix as a whole.The release of potassium about A and B dropped gentle release level at 15 and 45 days,and afterwards had been maintained at this gentle level.