Carbon Dioxide Supplementation for Plant Growth
Carbon is essential for plant growth as it forms the backbone of organic molecules crucial for plant development. Through the process of photosynthesis, plants absorb carbon dioxide (CO2) from the atmosphere and convert it into carbohydrates, such as sugars and starches, which serve as energy sources for the growing plant. Carbon also plays a key role in the formation of cellulose, proteins, lipids, and other important molecules necessary for plant structure and function.
In addition to being a building block for organic molecules, carbon also influences plant growth indirectly through its role in soil fertility. Organic matter in soil, which contains carbon, provides nutrients and improves soil structure, water retention, and aeration, all of which are vital for healthy plant growth. Carbon in the form of organic matter acts as an energy source for soil microorganisms. These microorganisms play a critical role in maintaining soil fertility and health by breaking down organic material, recycling nutrients, and suppressing soil-borne diseases.
Atmospheric concentration of CO2 limits plant growth by placing a restriction on the how quickly plants are able to perform photosynthesis. The limiting effect of CO2 can be even more pronounced within indoor cultivation areas like greenhouses or grow tents, which tend to limit air exchange to control environmental parameters like temperature and humidity.
Scientific studies have demonstrated that for most plants increasing CO2 levels to roughly double that of atmospheric conditions, approximately 800-1000ppm, improves the rate of plant growth by providing more CO2 for plants to fix thus increasing the rate photosynthesis.
How does CO2 supplementation improve plant growth?
Photosynthesis
CO2 is a fundamental component of photosynthesis, the process by which plants convert light energy into chemical energy. Higher CO2 levels increase the rate of photosynthesis, particularly in C3 plants, which make up the majority of plant species, including major crops like wheat, rice, and soybeans. These plants typically experience limited photosynthesis at atmospheric CO2 levels, so increasing CO2 can boost their photosynthetic efficiency and biomass production.
Ideal Crop Temperature
Higher CO2 levels can increase a plant's tolerance to heat stress. This occurs because elevated CO2 can help reduce photorespiration, a process that becomes more problematic at higher temperatures and reduces photosynthetic efficiency. As a result, plants may be able to sustain growth and yield at temperatures higher than their current optimal range. Enzymatic reactions occur at increased rate with higher temperatures, and therefore supplementing additional CO2 you can increase the temperature of your growing environment and therefore improve the growth rate in your crop.
Water Use Efficacy
Elevated CO2 improves water use efficiency by causing partial stomatal closure, which reduces transpiration. This improved water use efficiency can help plants cope with higher temperatures by maintaining hydration and reducing heat stress, potentially allowing crops to tolerate higher temperatures better.
How to supplement CO2 in your growing environment?
Mushroom bags
Using mushroom bags to supplement CO2 levels in plant cultivation involves capitalizing on the natural respiration process of mushrooms. As mushrooms grow, they respire, consuming oxygen and emitting carbon dioxide (CO2) as a by-product. By strategically placing mushroom cultivation bags within a greenhouse or growing area, the CO2 produced during mushroom growth can be harnessed to elevate CO2 levels for nearby plants. This approach leverages the symbiotic relationship between mushrooms and plants, as the CO2 emitted by mushrooms enhances photosynthesis and promotes plant growth. Additionally, using mushroom bags for CO2 supplementation is cost-effective and sustainable, as it utilizes agricultural waste products as substrates for mushroom cultivation, contributing to a circular economy model within agriculture.
Gas injection
This method of CO2 supplementation involves utilisation of pressured carbon dioxide gas cylinders and offers precision in CO2 supplementation, allowing growers to tailor CO2 levels to meet the specific needs of their crops throughout different growth stages. CO2 supplementation using gas injection requires the use of electronic controllers and precision sensors to ensure that CO2 levels do not rise to a toxic level.