Fundamental Studies on Factory - Style Plant Production

对工厂式工厂生产系统所涉及的基本问题进行了研究。在第一年，设计和建造了一个类似于人工照明的植物工厂的生长室。作为人造光源，选择高压钠灯是因为其将电转换为光的效率最高。生菜作为试验植物，在水培系统中生长，该系统也是我们开发的。三种不同床层的液液电导率和pH值由计算机自动调节。利用所研制的系统，研究了光照强度、光照周期和明暗比对生菜生长的影响，并分析了溶液电导率的变化对生菜蒸腾的影响。光照周期的变化对生长速率和干物质增加率没有影响，但叶片形状有轻微变化。生长速率随光照期和光照强度的增加而增加，而鲜重增重比则随光照期和光照强度的增加而降低。结果表明，溶液浓度的变化与施肥引起的浓度增加、供水引起的浓度变化和植物吸收引起的浓度变化之间存在明显的关系。从我们的实验中也可以看出，EC水平的下降与综合蒸腾量的下降是相关的。

A study has been conducted on the fundamental problems which are involved in the factory-style plant production system. In the first year, a growth chamber similar to a plant factory with artificial lights was designed and constructed. As an artificial light source, high pressure sodium lamps were selected because of their highest efficiency to convert electricity to light. Lettuce was used as a test plant and was grown in a hydroponic system which was also developed by us. The levels of EC (Electrical Conductivity of liquid solution) and pH in the liquid solution in three different beds were automatically adjusted by the computer.The effect of light intensity, light period and the ratio of light and dark period on lettuce growth was examined and the effect of the change of EC (electrical conductivity of liquid solution) on the transpiration of lettuce was also analysed using the system we developed.The growth rate and the ratio of dry matter increase were not affected by the change of light period but the shape of leaves was slightly changed. The growth rate increased with the increase of light period and light intensity, on the other hand, the ratio of fresh weight increase was decreased according to the increase of light intensity and light period.It was found that there is a clear relationship among the change of solution concentration, the concentration increase due to the addition of fertilizers, the concentration change due to water supply and that by plant uptake. It was also clear from our experiment that the decrease of EC level and integrated transpiration amount can be correlated.