Climate change is pushing rice-producing regions to temperatures far\nhigher than those ever experienced during 9,000 years of rice\ncultivation. A new study shows that current global warming is unfolding\nabout 5,000 times faster than the rate of evolutionary change rice has\npreviously endured. The lead author, anthropologist and geographer\nNicolas Gauthier of the Florida Museum of Natural History, explains that\nwhile humans can breed heat-tolerant varieties or relocate fields to new\nregions, future warming is expected to cause serious disruption for\nbillions who depend on rice for their livelihoods.<\/p>\n
\u201cWe do not want to downplay human adaptability,\u201d Gauthier told Live\nScience. \u201cBut we also want to acknowledge that adaptation has occurred,\nand in some cases we may be closer to the edge of what can be reasonably\nadapted within that timescale.\u201d<\/p>\n
Rice is a staple for more than half the world\u2019s population, with 90%\nof cultivation occurring in Asia. According to the World Economic Forum\n(WEF), some rice-producing regions have already begun to feel the\neffects of extreme warming, directly impacting yields.<\/p>\n
Although rice is a crop that loves warmth, the photosynthetic process\nhalts at around 40 C (104 F). Excessively high temperatures also damage\npollen viability and grain development. Beyond temperature, rice is\nhighly water-dependent, so shifts in monsoon and dry-season rainfall\ncreate major constraints. Rising sea levels threaten low-lying paddies\ninundated with saltwater, which can kill the crop.<\/p>\n
Gauthier and his team gathered palaeoclimate data from archaeological\nsites containing evidence of rice cultivation over nearly a millennium.\nIn their report published in Communications Earth & Environment,\nthey found that humans historically expanded rice cultivation into\ncooler regions through breeding cold-tolerant varieties. However, the\nupper temperature limit has remained unchanged since the start of rice\ncultivation 9,000 years ago.<\/p>\n
Throughout history, rice agriculture has been limited to areas with\naverage annual temperatures below 28 C (82.4 F) and average maximum\nsummer temperatures below 33 C (91.4 F). Gauthier adds that climate\nchange could warm areas previously too cold for rice, enabling\ngeographic shifts. But moving long-established farming areas is not easy\nand would trigger large-scale economic and food-security impacts.<\/p>\n
\u201cYou could keep global rice production level by moving cultivation\nlocations,\u201d he says. \u201cBut that does not solve the problem for people in\nSouth Asia who depend on rice for their daily consumption.\u201d<\/p>", "url": "https:\/\/jawawa.id\/newsitem\/climate-change-pushes-rice-growing-regions-beyond-temperature-limits-in-9-000-years-of-human-history-1779545825", "image": "" }, "sponsor": "Okusi Associates", "sponsor_url": "https:\/\/okusiassociates.com" }