New maps show that the Earth is rapidly running out of fertile land and that food production will soon be unable to keep up with the world's burgeoning population. The maps reveal that more than one- third of the world's land is being used to grow crops or graze cattle.
Scientists at the University of Wisconsin-Madison combined satellite land cover images with agricultural census data from every country in the world to create detailed maps of global land use. Each grid square was 10km across and showed the most prevalent land use in that square, such as forest, grassland or ice.
"In the act of making these maps we are asking: where is the human footprint on the Earth?" said Amato Evan, a member of the University of Wisconsin-Madison research team presenting its results this week at a meeting of the American Geophysical Union in San Francisco.
The current map shows a snapshot of global land use for the year 2000, but the scientists also have land use data going back to 1700, showing how things have changed.
"The maps show, very strikingly, that a large part of our planet [roughly 40 percent] is being used for either growing crops or grazing cattle," said Navin Ramankutty, a member of the Wisconsin-Madison team.
By comparison, only 7 percent of the world's land was being used for agriculture in 1700. The Amazon basin has seen some of the greatest changes in recent times, with huge swaths of the rainforest being felled to grow soya beans.
"One of the major changes we see is the fast expansion of soybeans in Brazil and Argentina, grown for export to China and the EU," Ramankutty said.
This agricultural expansion has come at the expense of tropical forests in both countries. Meanwhile, intensive farming practices mean that cropland areas have decreased slightly in the US and Europe and the land is being gobbled up by urbanization. The research indicates that there is now little room for further agricultural expansion.
"Except for Latin America and Africa, all the places in the world where we could grow crops are already being cultivated. The remaining places are either too cold or too dry to grow crops," Ramankutty said.
The scientists hope that by continuing to monitor changes in land use, they will be able to highlight problems and help find solutions.
"The real question is, how can we continue to produce food from the land while preventing negative environmental consequences such as deforestation, water pollution and soil erosion?" Ramankutty said.
In other environmental news, scientists now now believe the role of snow in maintaining the Earth's climate is far more important than previously thought. According to a new climate model in which researchers imagined a world without snow, not only would global temperatures rise but, bizarrely, the amount of permanently frozen land in the world would also go up.
Losing every last snowflake in the world is an unlikely scenario. But global warming is expected to melt around 10 to 20 percent of the world's snow in the future and, by modeling the no-snow climate, Stephen Vavrus from the University of Wisconsin-Madison was able to work out how the predicted melting would affect the planet. Snow tends to cool the air above it and stops the Earth from overheating. Vavrus found that, in a world without snow, the temperatures in the northern hemisphere rocketed.
"Without snow we see a large atmospheric warming of up to 5?C over northern Eurasia and North America annually [8-9?C in winter], and a globally averaged warming of 0.8?C," he said.
Snow provides a warm insulating blanket and without it vast areas of land would become permanently frozen.
"Soils in presently snow-covered areas, such as Siberia, would cool considerably, by up to 20?C during winter. As a result, the permafrost would expand equatorwards by 500 to 1,000km, even though the overlying air warms by several degrees," said Vavrus, who will present his findings at the American Geophysical Union meeting this week.
Showcasing phallus-shaped portable shrines and pink penis candies, Japan’s annual fertility festival yesterday teemed with tourists, couples and families elated by its open display of sex. The spring Kanamara Matsuri near Tokyo features colorfully dressed worshipers carrying a trio of giant phallic-shaped objects as they parade through the street with glee. The festival, as legend has it, honors a local blacksmith in the Edo Period (1603-1868) who forged an iron dildo to break the teeth of a sharp-toothed demon inhabiting a woman’s vagina that had been castrating young men on their wedding nights. A 1m black steel phallus sits in the courtyard of
HIGH HOPES: The power source is expected to have a future, as it is not dependent on the weather or light, and could be useful for places with large desalination facilities A Japanese water plant is harnessing the natural process of osmosis to generate renewable energy that could one day become a common power source. The possibility of generating power from osmosis — when water molecules pass from a less salty solution to a more salty one — has long been known. However, actually generating energy from that has proved more complicated, in part due the difficulty of designing the membrane through which the molecules pass. Engineers in Fukuoka, Japan, and their private partners think they might have cracked it, and have opened what is only the world’s second osmotic power plant. It generates
JAN. 1 CLAUSE: As military service is voluntary, applications for permission to stay abroad for over three months for men up to age 45 must, in principle, be granted A little-noticed clause in sweeping changes to Germany’s military service policy has triggered an uproar after it emerged that the law requires men aged up to 45 to get permission from the armed forces before any significant stay abroad, even in peacetime. The legislation, which went into effect on Jan. 1 aims to bolster the military and demands all 18-year-old men fill out a questionnaire to gauge their suitability to serve in the armed forces, but stops short of conscription. If the “modernized” model fails to pull in enough recruits, parliament will be compelled to discuss the reintroduction of compulsory service, German
Hundreds of Filipinos and tourists flocked to a sun-bleached field north of Manila yesterday, on Good Friday, to witness one of the country’s most blood-soaked displays of religious fervor, undeterred by rising fuel prices. Scores of bare-chested flagellants with covered faces walked barefoot through the dusty streets of Pampanga Province’s San Fernando as they flogged their backs with bamboo whips in the scorching heat. Agence France-Presse (AFP) journalists said they saw devotees deliberately puncturing their skin with glass shards attached to a small wooden paddle to ensure their bleeding during the ritual, a way to atone for sins and seek miracles from
RSS