JPS6344767Y2 - - Google Patents

Description

[Detailed description of the invention] The assimilation box method is generally used to measure photosynthesis in plants. In other words, a plant is housed in an airtight container, the plant is irradiated with light, and air is circulated through the container to detect the difference in carbon dioxide concentration between the inlet and outlet, and this concentration difference and the amount of air flow are detected. The purpose is to find the amount of carbon dioxide gas absorbed by plants. However, at the same time that plant leaves absorb carbon dioxide through photosynthesis, the roots and various symptomatic organisms in the surrounding soil perform respiration, absorb oxygen and release carbon dioxide, regardless of light irradiation. There is. For this reason, in conventional devices, a difference between the amount of carbon dioxide absorbed by leaves through photosynthesis and the amount of carbon dioxide released by the respiration of roots and other symptomatic organisms is observed, and the amount of carbon dioxide gas absorbed by photosynthesis is There was a drawback that the amount of absorption could not be measured accurately. Therefore, the present invention eliminates these drawbacks.

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention, in which a sample plant 2 is placed inside an assimilation box 1, at least a part of which is made of a transparent plate such as acrylic resin, so that external light can be irradiated inside. It accommodates. The plant 2 is planted in a pot 3, and a pot storage box 4 made of an acrylic resin board or the like is provided inside the assimilation box 1. FIG. 2 is a longitudinal cross-sectional view of this pot storage box 4, and FIG. 3 is a plan view.
As shown in the figure, it is led out to the outside of the assimilation box 1 and connected to a relatively small capacity air pump 7. Further, the upper surface of the main body 5 is provided with cover plates 8 ₁ and 8 ₂ divided into two at the center, and a hole 9 through which the stem of the plant 2 passes is formed on the dividing line. That is, the stem of the plant 2 is placed in the hole 9 by placing the pot 3 in which the plant 2 is planted inside the main body 5, and placing the cover plates 8 ₁ and 8 ₂ on the pot 3 with the gasket 10 placed on its edge. The cover plates 8 ₁ , 8 ₂ are fixed with spring-loaded clamp fittings 11 , 11 . . . Furthermore, an outside air intake pipe 1 is installed at an appropriate position in the assimilation box 1 that houses the plants 2.
2 is connected to a discharge pipe 13, and the suction pipe 12, for example, is connected to an air pump 14 having a relatively large capacity. The joint between the suction pipe 12 and the discharge pipe 13, and thus the air suction and discharge ports in the assimilation box 1, are connected to a carbon dioxide (CO ₂ ) analyzer 17 through conduits 15 and 16, and the carbon dioxide between them is In addition to measuring the difference in gas concentration, the suction pipe 1
2 is provided with a flow meter 18.

In such a device, when the pump 14 is activated, outside air is sucked in through the suction pipe 12, flows through the assimilation box 1 as shown by arrow a, and is exhausted to the outside through the exhaust pipe 13. When the pump 7 is started, the air inside the assimilation box 1 is sucked into the pot storage box 4 through the space around the stem in the through hole 9, and is discharged into the atmosphere from the exhaust pipe 6 as shown by arrow b. . That is, since the air in the container box 4 is sucked by the pump 7, an air current is generated in the hole 9 in which the air in the assimilation box 1 necessarily flows into the pot container box 4 as shown by arrow b. Furthermore, a pump 7 having a smaller capacity than the pump 14 is provided so that there is no possibility of a reverse airflow occurring. In this state, when the plant 2 in the assimilation box 1 is irradiated with external light, carbon dioxide gas in the air is absorbed by the leaves through photosynthesis. Therefore the conduit 15,
At 16, a part of the air at the inlet and outlet of the assimilation box 1 is sampled, and the analyzer 17 measures the concentration difference of carbon dioxide (CO ₂ ), and the flow rate at the flow meter 18 and
The amount of photosynthesis of the plant 2 can be calculated based on the above concentration difference. In addition, in this case, carbon dioxide gas is released by the respiration of the roots of the plants inside the pot 3 and the symptomatic organisms around them. However, the carbon dioxide gas is pumped into the pump 7 together with the air inside the pot storage box 4.
Since it is sucked in and directly discharged into the atmosphere through the exhaust pipe 6, it has no effect on the measurement of the concentration difference by the analyzer 17, and therefore the amount of photosynthesis by the leaves of the plant 2 can be accurately determined. .

[Brief explanation of the drawing]

Figure 1 is a diagram showing the configuration of an embodiment of the present invention, Figure 2 is a diagram showing the configuration of an embodiment of the present invention.
The figure is a longitudinal sectional view of the pot storage box in FIG. 1, and FIG. 3 is a plan view of the pot storage box. In the figure, 1 is an assimilation box, 2 is a plant, 3 is a pot, 4 is a pot storage box, 6 is an air discharge pipe, 7 is a pump, 9 is a hole, 12 is an intake pipe, 13 is a discharge pipe, 1
4 is an air pump, 17 is a carbon dioxide gas analyzer, 18
is a flow meter.

Claims (1)

[Scope of utility model registration request] An assimilation box for accommodating a plant planted in a pot is provided with a pot storage box having a through hole for the stem of the plant, and an air exhaust pipe that sucks the air inside the pot storage box and discharges it to the outside world. and an air pump for circulating air through the assimilation box, and an air inlet and an air outlet in the assimilation box are connected to a gas spectrometer that detects a difference in carbon dioxide concentration therebetween.