Plants require carbon dioxide for growth. It is a necessary ingredient for photosynthesis in which the plant creates glucose and structural carbon that forms the plant body. According to Nature Education, approximately 96 percent of the typical dry plant mass is due to compounds created through photosynthesis using carbon dioxide.
While the human-caused increase in carbon dioxide receives the blame for global warming, it also impacts plant growth. Experiments by Nature Education show most of the benefits to be positive in plant growth. Increasing carbon dioxide concentration increases the rate of growth for most, but not all plants. In addition, the amount of fruit the plant produces increases. The plants absorb carbon dioxide through the stoma of the leaves. However, opening the stoma increases transpiration, or water loss, for the plant. Most plants regulate the time the stoma are opened to conserve water. In atmospheres with greater concentrations of carbon dioxide, the plant is able to absorb more of the gas while still limiting water loss, increasing growth rate.
Growth of plants depends on more than just carbon dioxide. The plants need minerals and water to sustain the growth process. An increase in carbon dioxide concentrations in the air does not necessarily mean these other requirements are available. Thus, while increasing carbon dioxide encourages greater growth, it does not guarantee it.