Beijing has been shrouded in orange dust as a strong sandstorm blew hundreds of miles from drought-struck northern China to the nation's capital.

In Tiananmen Square, clouds of dust obscured monuments, while visitors wore masks to avoid the dust and soil in windy conditions.

A level five pollution warning was issued in the hazardous conditions, and people were urged to stay indoors.

The storm also hit Xinjiang and Inner Mongolia, Shanxi, Shaanxi and Hebei.

On Saturday it had spread over an area of 810,000 sq km with a population of 250 million, official news agency Xinhua reported.

NAIROBI, Mar 19, 2010 (IPS) - After torrential rains and floods claimed lives in Kenya's North Rift region, hundreds of displaced people are now in dire need of relief aid.

In Turkana, one of the worst affected areas, hundreds of homes have been washed away by floods or buried under landslides. Access to clean water and sanitation have become a major issue in the area, where the displaced have to relieve themselves in bushes.

"My house was suddenly filled with water. My toilet was carried away, and also the vegetables, which I had planted on my farm," lamented Godfrey Chume, one of the displaced residents in the Turkana area.

The father of two said he gathered up his family members and quickly ran up a hill to be swept away by the torrents. "My boys came down with a fever. For now, my family is staying with neighbours, as I work towards rebuilding what was destroyed," Chuma told IPS.

Strong flood waters caused the Kerio river to burst its banks in the area in early March, destroying irrigation schemes, roads as well as fields, especially sorghum and maize crops, which is likely to result in food shortages for many months to come.

Chume says his and other families, who live in a settlement called California, in the Turkana district, say they have not been reached by any of the relief aid distributed by government and non-governmental organisations. They have been struggling to put enough food on the table and have used their little savings to buy from a nearby town. But in the long-run, they will end up in a difficult situation, Chume believes, because their livelihoods depend on the yields from their farmlands.

NASA scientists analyzing 30 years of satellite data have found that the amount of ultraviolet (UV) radiation reaching Earth's surface has increased markedly over the last three decades. Most of the increase has occurred in the mid-and-high latitudes, and there's been little or no increase in tropical regions.

The new analysis shows, for example, that at one line of latitude - 32.5 degrees - a line that runs through central Texas in the northern hemisphere and the country of Uruguay in the southern hemisphere, 305 nanometer UV levels have gone up by some 6 percent on average since 1979.

The primary culprit: decreasing levels of stratospheric ozone, a colorless gas that acts as Earth's natural sunscreen by shielding the surface from damaging UV radiation.

The finding reinforces previous observations that show UV levels are stabilizing after countries began signing an international treaty that limited the emissions of ozone-depleting gases in 1987. The study also shows that increased cloudiness in the southern hemisphere over the 30-year period has impacted UV.

The domestication of animals and plants is the most important technological innovation during human history. This genetic transformation of wild species has occurred as humans have used individuals carrying favorable gene variants for breeding purposes. In the current issue of Nature an international team led by researchers at Uppsala University has revealed some of the secrets underlying the remarkable development of the domestic chicken.

The domestic chicken has in recent years become the most important and cost-effective source of animal protein world-wide. In the beginning of the 20th century specialized layer (egg-producing) and broiler (meat-producing) chickens were developed. The approach has been remarkably successful and has led to huge improvements in productivity.

"The strategy to study four different populations of layer chickens as well as four broiler populations allowed us to reveal genetic changes of crucial importance for chicken domestication in general as well as changes that were essential for the development of layers or broilers", says Leif Andersson who coordinated the study.

Federal limits on water that can be pumped out of a major river delta for California farmers are scientifically justified, a much-anticipated report said on Friday, a finding hailed by environmentalists in the state's epic water wars.

But the National Academy of Sciences stopped short of handing a decisive victory to environmental interests over agricultural interests. The academy said further study was required and that threats to Chinook salmon, delta smelt and other endangered fish were not entirely caused by the pumping.

"The Academy of Sciences report clearly validates the biological opinions," Ann Hayden, a senior water resource analyst for the Environmental Defense Fund, said of regulations devised under court order by federal wildlife biologists and issued in late 2008.

"It's time to stop pitting the economic interests of farmers against fishermen and move forward to find solutions," Hayden said. "We have pushed the Bay-Delta system to the brink of collapse and saving it -- and the jobs that depend on it -- is going to require increased cooperation among all interests."