Carbon dioxide solvents such as organochlorides. It is used by some dry cleaners for this reason (see green chemistry). It is used in the preparation of some aerogels because of the properties of supercritical carbon dioxide. Plants require carbon dioxide to conduct photosynthesis. The atmospheres of greenhouses may (if of large size, must) be enriched with additional to sustain and increase the rate of plant growth. At very high concentrations (100 times atmospheric concentration, or greater), carbon dioxide can be toxic to animal life, so raising the concentration to 10,000 ppm (1%) or higher for several hours will eliminate pests such as
Ocean storage of carbon dioxide dioxide is 10,000 years for a 50 m deep lake. This number is decreased by more than 25 times with currents from ocean bottom storms. Sites would be chosen based on ocean floor depth, seismic and volcanic activity, and the presence of CaCO deposits that could increase the rate of carbon mineralization. Some sites proposed for storage at depths greater than 6 km include the Indonesian Sunda trench, the Japanese Ryukyu trench, and the Puerto Rico trench. Researchers are studying how ecosystems are affected before and after injection of liquid carbon dioxide through "process studies, surveys of biogeochemical tracers, and