How can we tap into water security?

A global environmental crisis is gradually bubbling to the surface. It may not be apparent to those suffering the rainy seasons or annual floods, but to those in areas where fresh water is in short supply the insidious nature of the crisis is increasingly obvious: Human activities have disturbed the water cycle in ways we could not have foreseen in the pre-industrial era. Once mighty rivers, such as the Yellow River and the Indus, do not bring as much water to the seas as they once did, once fertile lands have eroded and become desert and groundwater aquifers are so overdrawn that our hidden stores are now dwindling at alarming rates and not being replenished.

As Olli Varis of Aalto University, in Espoo, Finland, explains in the Foreword to a unique Special Issue of the International Journal of Sustainable Society, “The water quality problems of surface and groundwater are growing increasingly severe. Land use changes and climate factors cause the increase of damage and calamity due to floods, storms and droughts.” Varis points out that increasing urbanisation and human congestion are amplifying the problem with more than a billion people already living in slums deprived of fresh water and sanitation services quality of life for many is falling.

Water supply and sanitation are a human right, critically important to welfare and health, dignity and security alike as well as underpinning economic development. Varis notes how much agriculture depends on good water supply, how the development of emerging economies hinges on its presence and how energy, both conventional and renewable, are driven by water. It is inevitable that in those parts of the world where nations share water sources that friction will occur, especially if one nation’s water usage is detrimental to the other’s economic growth.

“Economic growth is desperately needed if poverty is to be reduced, Varis says, “but growth alone is not sufficient if growth polarises society.” Within a generation, we might expect at least two-thirds of the world population to be urbanised with all the increasing demands that will place on water supply particularly in China and Asia, South America and Africa.

The Special Issue of the journal draws together various analyses of the role of water supply, development, climate change and the potential for so-called “water wars”, opening up the debate and offering ideas for the mitigation of conflicts, tensions and rivalries through improved water governance and enhanced institutional development, particularly on the international stage so that we can all enjoy water security, peace and sustainability.

Special Issue on Water Wars in 21st Century along International Rivers Basins: Speculation or Reality?

The benefits of biotech to farmers

The biotech industry boosted farming across the globe to the tune of almost $65 billion during the period 1996 to 2009, according to the latest analysis published in the International Journal of Biotechnology. $65 billion is the increase in net farm income, the farm level benefit after paying for the seed and its biotech traits. The study’s authors estimate that almost half of that was derived by farmers in the developing world.

Graham Brookes and Peter Barfoot of PG Economics Ltd., in Dorchester, UK, have investigated the economic impact at the farm level of agricultural biotechnology, looking at yields, key costs of production, direct farm income, indirect (non-pecuniary) farm level income effects and impacts on the production base of the four main crops of soybeans, corn, cotton and canola. Biotech has added 83 million and 130 million tonnes, respectively, to global production of soybeans and corn, they estimate. Net farm level economic benefits amounted to almost $11 billion in 2009 alone.

“Biotech, and specifically genetically modified (GM) crops has had a significant positive impact on farm income derived from a combination of enhanced productivity and efficiency gains,” the team estimated. It has added 5.8% to the value of global production for the four main crops investigated, with cost savings being greatest for soy. In terms of the division between different parts of the world, the team reports that in 2009, 53.1% of the farm income benefits went to developing country farmers and the vast majority of those income gains were from GM insect-resistant cotton and GM herbicide-tolerant soybeans.

The team concedes that their estimate of benefits amounting to $65 billion is based on the assumption of average levels of weed and pest pressure. If the assumptions are varied to assume extremes of low weed and pest pressure in all years and high weed and pest pressure in all years, then then the farm level benefits from using biotech in agriculture during the period studied would fall within a range of about $58 billion to $73 billion.

Graham Brookes, & Peter Barfoot (2011). The income and production effects of biotech crops globally 1996-2009 Int. J. Biotechnol, 12

The slow rise of The Andes

The Andes is the world’s longest continental mountain range and the highest outside Asia, with an average elevation of 4000 metres. The question of how quickly the mountains reached such heights has been a contentious one that University of Michigan paleoclimatologist Christopher Poulsen and graduate student Nadja Insel working with Todd Ehlers of the University of Tuebingen in Germany, believe they may now have settled with a new interpretation of isotopic data. Their work suggests that the rise of the Andes was a very gradual process.

Poulsen’s uplifting work suggests that previous interpretations of the evidence have misconstrued changes in oxygen isotope ratios as being due to a rapid rise of the mountain range whereas the more likely explanation is that the changes are due to shifts in ancient climate.

“In the modern climate, there is a well-known inverse relationship between oxygen isotopic values in rain and elevation,” Poulsen explains.
“As a rain cloud ascends a mountain range, it begins to precipitate.
Because atoms of oxygen-18 are more massive than those of oxygen-16, it is preferentially rained out. Thus, as you go up the mountain, the precipitation becomes more and more depleted in oxygen-18, and the ratio of oxygen-18 to oxygen-16 decreases.” Geologists use the ratio of these isotopes, preserved in rock, to infer past elevations and so the rate of rise of a mountain range.

“If the ratio decreases with time, as the samples get younger, the interpretation would typically be that there has been an increase in elevation at that location,” Poulsen adds. He points out that that is the precise conclusion drawn by a series of papers on the uplift history of The Andes published over the past four years. On the basis of oxygen isotope ratios determined by analysis of carbonate rocks, the authors of those papers suggested that the central Andes rose about 2500 to 3500 metres in a mere three million years, Other geologists had assumed that the rise to those heights took place over tens of millions of years.

Unfortunately, elevation is not the only thing to disturb oxygen isotope ratios in precipitation. “It can also be affected by where the vapour came from and how much it rained,” says Poulsen. “More intense rainfall also causes oxygen-18 to be preferentially precipitated.” He and his colleagues were skeptical of the rapid-rise scenario, and so performed climate modelling experiments to investigate whether something other than altitude might have given rise to the shift in ratio observed in carbonate deposits.

Andes: Credit to http://www.flickr.com/photos/atyt/

“The key result in our modelling study is that we identified an elevation threshold for rainfall,” Poulsen says. “Once The Andes reached an elevation greater than 70 percent of the current elevation, the precipitation rate abruptly increased. In our model, the increased precipitation also caused the ratio of oxygen-18 to oxygen-16 to significantly decrease. Our conclusion, then, is that geologists have misinterpreted the isotopic records in the central Andes. The decrease in the ratio is not recording an abrupt increase in elevation; it is recording an abrupt increase in rainfall.”

This conclusion is backed up by geochemical and sedimentological data, Poulsen said. “There is evidence that the central Andes became less arid at the same time that the isotope records show a decrease in the ratio of oxygen-18 to oxygen-16.”

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Christopher Poulsen

Science Express, 2010, online