设施栽培中营养液成分的在线检测

The On-line Measurement of the Nutritive Medium Ingredient in Greenhouse Culture

设施栽培中为了加强营养液的管理并循环使用营养液 ,需在线检测营养液的 EC值、p H值和各种养分的含量 ,及时调配营养液以达到养分均衡。本文利用离子选择性电极实现了对氮、钾、钙等离子浓度以及 EC值和 p H值的在线检测 ,并根据各营养元素浓度在特定作物特定生长期及生长环境相对稳定的一段时期内与 EC值、p H值之间相对稳定的关系 ,以及各营养元素之间变化关系实现了磷、硫和镁离子浓度的软测量。

In order to reinforce the nutritive medium management and to recycle the nutritive medium in greenhouse culture, it is required to measure the value of EC, pH and the content of nutrients on line, thus adjust every ingredient to equilibrium in time. In this paper, application of ion selective electrode implements the on line measurement of some ingredients, such as the concentrations of ions of Nitrogen, Kalium, and Calcium, EC and pH, and implements the soft sense of the concentrations of ions of Phosphorus, Sulfur and Magnesium according to the relative stable relation of concentrations of every ingredient and the value of EC, pH in a period when growth circumstance is relatively stable for special crop in special growing period, as well as the relation among variation of every ingredient.