Final answer:
CO2 concentrations in a closed chamber used to estimate NPP are measured using methods such as the infrared gas analyzer technique and the closed chamber method. These methods involve measuring the change in CO2 concentration over time and using it to estimate the photosynthetic activity and NPP of the plant.
Step-by-step explanation:
CO2 concentrations in a closed chamber used to estimate NPP (Net Primary Production) are measured through various methods. One common method is the infrared gas analyzer (IRGA) technique. In this method, a chamber is sealed over a plant or vegetation, and the gas analyzer measures the change in CO2 concentration over time. By measuring the rate of change in CO2 concentration, the photosynthetic activity and NPP of the plant can be estimated.
Another method is the closed chamber method, where the chamber is sealed to measure changes in CO2 concentration. The chamber is usually equipped with sensors that measure CO2 concentration over time, and these measurements are used to estimate NPP. The chamber can also be connected to a gas analyzer or spectrometer to measure CO2 levels more accurately.It is important to note that these methods provide estimations of NPP based on changes in CO2 concentration, and other factors such as temperature, light, and water availability also affect NPP.