Rice cultivation on wetland rice fields is thought to be responsible for 11% of the anthropogenic methane emissions. Rice requires slightly more water to produce than other grains. Rice production uses almost a third of Earth’s fresh water.
Long-term flooding of rice fields cuts the soil off from atmospheric oxygen and causes anaerobic fermentation of organic matter in the soil. Methane production from rice cultivation contributes ~1.5% of anthropogenic greenhouse gases. Methane is twenty times more potent a greenhouse gas than carbon dioxide.
A 2010 study found that, as a result of rising temperatures and decreasing solar radiation during the later years of the 20th century, the rice yield growth rate has decreased in many parts of Asia, compared to what would have been observed had the temperature and solar radiation trends not occurred. The yield growth rate had fallen 10–20% at some locations. The study was based on records from 227 farms in Thailand, Vietnam, Nepal, India, China, Bangladesh, and Pakistan. The mechanism of this falling yield was not clear, but might involve increased respiration during warm nights, which expends energy without being able to photosynthesize.
Nematodes
Several nematode species infect rice crops, causing diseases such as Ufra (Ditylenchus dipsaci), White tip disease (Aphelenchoide bessei), and root knot disease (Meloidogyne graminicola). Some nematode species such as Pratylenchus spp. are most dangerous in upland rice of all parts of the world. Rice root nematode (Hirschmanniella oryzae) is a migratory endoparasite which on higher inoculum levels will lead to complete destruction of a rice crop. Beyond being obligate parasites, they also decrease the vigor of plants and increase the plants' susceptibility to other pests and diseases.
-wikipedia.
Long-term flooding of rice fields cuts the soil off from atmospheric oxygen and causes anaerobic fermentation of organic matter in the soil. Methane production from rice cultivation contributes ~1.5% of anthropogenic greenhouse gases. Methane is twenty times more potent a greenhouse gas than carbon dioxide.
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Work by the International Center for Tropical Agriculture to measure the greenhouse gas emissions of rice production.
A 2010 study found that, as a result of rising temperatures and decreasing solar radiation during the later years of the 20th century, the rice yield growth rate has decreased in many parts of Asia, compared to what would have been observed had the temperature and solar radiation trends not occurred. The yield growth rate had fallen 10–20% at some locations. The study was based on records from 227 farms in Thailand, Vietnam, Nepal, India, China, Bangladesh, and Pakistan. The mechanism of this falling yield was not clear, but might involve increased respiration during warm nights, which expends energy without being able to photosynthesize.
Nematodes
Several nematode species infect rice crops, causing diseases such as Ufra (Ditylenchus dipsaci), White tip disease (Aphelenchoide bessei), and root knot disease (Meloidogyne graminicola). Some nematode species such as Pratylenchus spp. are most dangerous in upland rice of all parts of the world. Rice root nematode (Hirschmanniella oryzae) is a migratory endoparasite which on higher inoculum levels will lead to complete destruction of a rice crop. Beyond being obligate parasites, they also decrease the vigor of plants and increase the plants' susceptibility to other pests and diseases.
-wikipedia.
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