 Random news from the Archive Ozone reduces yields
20.11.2012
A team of scientists from the University of Illinois conducted field studies for two years on the effect of ozone on crop yields. The conclusions are disappointing: ozone can lead to a decrease in crop yields. The study was conducted on soybeans, but it may also apply to other equally important food plants.
People mostly think that ozone is high up in the upper atmosphere and protects the Earth from ultraviolet radiation. However, below the Earth's surface, ozone is a pollutant that has now been shown to cause serious damage to crops. Ozone is a chemically active substance that easily reacts with cell membranes and various proteins, which can cause respiratory damage in humans. Ozone also harms plants by slowing down photosynthesis and accelerating aging. As a result, plants absorb less carbon, which reduces yields. American scientists have proven for the first time that current levels of ozone pollution are already high enough to cause noticeable harm to agriculture.
In plants, ozone starts chemical reactions very quickly - immediately after entering the plant through the stomata in the leaves. As a result, other oxygen radicals can be formed, as well as hydrogen peroxide. Ultimately, a series of cascade reactions leads to a decrease in photosynthesis and stomatal conductivity. At a sufficiently high concentration of ozone, plant cells die, and this is clearly seen in the "burnt" leaves and black necrotic spots.
The scientists studied the response of 7 different soybean genotypes at 8 to 38 levels of ozone concentration (from 200 ppb to 36 ppb). The latter level is very high, but is often found in heavily polluted areas of China and India. The researchers found that any increase in ozone concentration had negative effects and led to a decrease in soybean yields: about half a bushel per acre (0,4 liters from 15 ha) for each additional part per billion. If you consider that the ozone concentration is increasing, then every year XNUMX bushels per acre are added to the loss.
It is estimated that further increases in ozone concentrations at this rate will increase soybean yield loss by 9-20% by 2030.
|
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese
All languages of this page