Anil Penna, Yahoo News 25 Nov 07;
From meat, poultry and milk to potatoes, onions and leafy greens, everything consumed on the world's dining tables is feeling the heat from climate change, scientists say.
Researchers are trying to establish the extent to which global warming will affect livestock, plant life and staple crops such as rice to bolster their resistance to disease and breed stronger varieties.
The world's billion poor, whether producers or consumers, will bear the brunt, warned scientists who ended a conference Saturday on agriculture and climate change in Hyderabad, southern India.
"In some ways, the time for doing things is already past," said John McDermott, deputy director of research at the Nairobi-based International Livestock Research Institute. "The changes are already happening."
As an example, rift valley fever, a deadly virus transmitted to sheep, cattle, camels and humans by mosquito bites, is being fuelled by climate change, the scientist said.
The virus is manifesting itself in broader swathes of East Africa and the Middle East because of climate variability in dry regions that helps vectors such as mosquitoes, tsetse flies and ticks to breed and spread, he said.
"What you see are diseases moving into areas where they have not been before, which means sometimes animals are exposed where they haven't been for a long time," he said.
"That leads to more outbreaks," McDermott added.
For the poor, livestock offers a livelihood as well as a savings bank they can tap, selling off their cows or chickens to deal with a health or family emergency.
"These are the people who don't make much of an impact on the ecological footprint of the world," said McDermott.
But they are also the people most at risk from damage wrought on livestock by diseases that could be aggravated by climate-related phenomena.
Scientists are also studying cropping and disease patterns in vegetables -- potatoes and tomatoes to cabbage and spinach, onion and garlic -- to see how they can cope with the stresses brought by global warming and its side-effects.
"If you make it a given that temperatures will go up, water will be a problem -- that will be your worst-case scenario," said Jackie Hughes, deputy director of research at the Shanhua, Taiwan-based World Vegetable Centre.
"You're going to have typhoons, cyclones and hurricanes," she said, adding vegetable growers may have to grow different varieties, use grafting techniques to address flooding and devise rain and insect protection for their crops.
"Probably, it will mean a shift of where crops are grown -- onions moving a little bit in one direction and tomatoes, cabbages coming out of very, very dry areas," she added.
Success in tackling the impact of climate change on crops is important as the world is host to a billion people who are already underweight and under-nourished, Hughes said.
The average adult is required to consume 74 kilogrammes of vegetables a year and "most don't reach that," she added.
Scientists are also concerned about the potential effect of climate change on potato blight, a weather-driven disease that takes a heavy toll on potato crops.
The pathogen that causes the blight is an "incredibly fast breeder," said Dyno Keatinge, deputy research head of the International Crops Research Institute here.
"So I am worried, you don't see me smiling in complacency," said Keatinge, who comes from Ireland where the disease caused a great famine in the 1840s.
