Posted on 22 November 2004
Sugarcane plantations in many tropical and sub-tropical countries have probably led to the largest losses of biodiversity of any single agricultural product, and sugar production today still has tremendous negative impacts on soil, water and air. New methods offer at least part of the solution: most rely on the use of better management practices (BMPs) in growing and processing sugar.
By Richard Holland*
The evidence that biodiversity conservation supports food production is mounting. Fisheries in the largely free-flowing Mekong River provide a basic protein source for tens of millions of people living in this region. Restoring wetlands near Dongting Lake in China’s Yangtze’s river has helped small farmers there to increase their income significantly through ducks and fish, instead of an irregular rice harvest that was affected by flooding. In southern India the traditional system of ‘tanks’ have for centuries provided water to grow food crops, supply drinking water and provide fertilizer for the fields, as well as providing habitat for pelicans, painted storks, and common cranes.
At the same time biodiversity is also under threat from farming, a fact which may actually reduce food security over the long-term. The United Nations Food and Agriculture Organisation (FAO) estimates that 13 million hectares of forest are lost to agriculture each year, affecting massive numbers of species and disrupting ecosystem services, such as flood control.
Ultimately we all depend on farmers for the food we buy and farmers, in turn, depend on a healthy environment to grow crops and raise animals. It should concern everyone that farming remains a largely unsustainable activity in many parts of the world, both rich and poor.
One crop stands out for special attention due to its probable negative impacts on human health as well as on nature: sugar. This is a product that most of us consume every day; indeed it is so common that most people do not give a second thought to where or how it is produced and with what consequences.
__________________________________________________World sugar production About 145 million tonnes of sugar produced worldwide each year with the leading producers being India, Brazil, the EU, USA and China. Sugar is an important crop that contributes to development in many poor countries by providing employment and reliable incomes for many.
It may come as a surprise therefore that sugarcane plantations in many tropical and sub-tropical countries have probably led to the largest losses of biodiversity of any single agricultural product. Although much of this habitat and species loss is historic, sugar production today -- whether from cane or beet – has a wide range of negative impacts on soil, water and air, including in parts of the world that environmental organizations, such as WWF, have identified as global treasures. The Great Barrier Reef, off Australia’s coast, which suffers from effluents and sediment from sugar farms, is one such case. The Konya basin in central Turkey, a vital nature conservation area, where more than 300,000 hectares of sugar beet require between 50 and 80 percent of the useable water in the basin, is another.
The environmental impacts of sugar growing and processing are highlighted in a new book from CABI Bioscience and WWF[i]
. This global review highlights the key impacts that sugar has on the environment worldwide which include habitat loss, overuse of water and chemicals, air and water pollution.
____________________________________________________________________Major environmental impacts of sugar Forest and wetland loss: A programme to use sugarcane as the raw material for fuel alcohol production led to the deforestation of new areas in the State of Alagoas, Brazil, such that only 3% of the original rain forest cover remains. Large areas of the Everglades wetland habitat have been reclaimed for the expansion of agriculture of which nearly 200,000ha is under cane cultivation, resulting in dramatic declines in biodiversity. In addition to habitat loss, ecosystem impacts include major redistribution of water flows and land subsidence.
Overuse of water and chemicals: Sugar cane is amongst a group of crops noted for their heavy water consumption (along with rice and cotton, for example). In the Indian state of Maharashtra, sugar cane covers just three percent of the land yet corners around 60% of the state irrigation supply and is a cause of substantial groundwater withdrawals; the water table has dropped from 40 feet to around 200 feet in the past 20 years. Overuse of chemicals: long-term experiments on the use of pesticides on sugar beet in Russia have demonstrated accumulation of toxic substances in roots and aerial parts of the crop plants, resulting in less growth and a decrease in sugar content when maximum doses were used. In the Tully River catchment (North Queensland) alone, the area under sugarcane and bananas doubled and Nitrogen fertiliser use increased by 130% between 1987 and 1999
Air pollution from pre-harvest burning and effluent from sugar mills: Substantially elevated levels of carbon monoxide and ozone in the atmosphere have been found around sugarcane fields in the state of Sao Paulo, Brazil, at the time of pre-harvest burning. Burning also contributes to a decrease in soil quality, by causing a decline in soil microbial activity and the physical and chemical properties of the soil. Discharge of water from two sugar factories and a distillery into a stream without proper treatment in the Gorakhpur district of Nepal rendered the water unfit for drinking, bathing or irrigation.
It seems clear, therefore, that our collective sweet tooth is causing significant ecological decay. But is there a way to stop the rot? Or even to repair the damage? There is no simple answer to this problem akin to a visit to the dentist.
However there are methods emerging in several sugar producing countries that appear to offer at least part of the solution. Most of these rely on the use of better management practices (BMPs)
in growing and processing sugar. The idea behind BMPs is that they provide a means, or several possible means, of tackling an environmental impact in such a way that the profitability of the farmer or factory is improved at the same time. In this way there can be sustained reduction in the impact, even in the absence of effective legal sanctions.
The installation of more efficient irrigation systems is one such way that can be used to reduce the excessive amounts of water that sugar sucks-up. Drip irrigations systems which deliver water to the crop plant or root zone are generally the most water efficient, followed by ‘centre-pivot’ sprinklers, furrow irrigation and finally flooding entire fields. In Swaziland, water application efficiencies for sugar cane have been estimated to be 72-89 percent under drip and centre pivot systems; In Pune, India, water savings in cane fields of 36 percent have been achieved by flooding alternate (rather than all) furrows. If part of the water saved is used for more production and part goes to maintaining flows in rivers or underground water storage, then there will be a benefit to the farmer and to local ecosystems.
Reducing chemicals used in sugar production is equally complex due to the myriad of local circumstances under which sugar is grown. However in many cases BMPs have been found that deliver significant improvements. A 50 percent reduction in total nitrate inputs to beet fields in the UK has been shown would only result in yield reductions of only 10 percent, but with considerably larger cost savings. Similarly, the use of waste cane leaves to make ‘trash blankets’ that cover the soil has been found to both increase soil moisture, reduce soil loss and the amount of fertilizer needed in South Africa.
There are also successful examples of integrated pest management (IPM) approaches in sugarcane that combine pest control by using natural predators with mechanical control methods and much reduced quantities of insecticides. In Guyana, for example, populations of the froghopper pest in cane declined to low levels after attempts at chemical control were stopped. This reduction in pest numbers was due to the recovery of existing natural enemy populations once the insecticide treatment was stopped.
It is becoming clear that the use of such better management practices (BMPs) for sugar should be able to offer significant financial benefits to farmers and to businesses. For farmers, millers and manufacturers they can create increases in farm output and cost efficiencies, as well as help ensure quality and reliable production. The companies that use BMPs, or require them to be used in the sugar they buy, should present fewer risks to investors and could also lead to higher returns. Why then are these BMPs not just taking off?
In a few countries, such as South Africa or Australia, the use of such practices is beginning but there are constraints to expansion. These range from knowledge about BMPs not being readily accessible for farmers, a lack of affordable credit for investments needed and the reluctance of farmers to change from what they know.
A substantial part of the responsibility for encouraging change lies of course with the sugar mills, farmers associations and government extension agencies in the main sugar producing countries. However there is also a significant role in supporting and accelerating progress in adopting BMPs that could be played by the European Union and by multinational companies that buy massive quantities of sugar.
The recent World Trade Organisation ruling that the European Union is illegally dumping 2.8 million of tonnes of subsidised sugar on world markets is thought likely to lead to a shift in sugar production worldwide as well as a rise in the world price in coming years; sugar prices in the EU are four times the current world price with consumers paying more as a consequence.
However, even cutting sugar production in the EU by as much as 10 million tones is unlikely to encourage more sustainable sugar production in itself. The EU needs to take positive measures as well. Experts suggest that it could do this by granting preferential access to environmentally sustainable sugar from developing countries and reallocating money from its common agricultural policy (CAP)
to finance development aid packages that are linked to raising environmental and labour standards in producing countries. Otherwise, more sugar growing in the developing world could also mean more damage to biodiversity and livelihoods, further undermining food security.
In addition to this, multinationals, such as Nestlé, Unilever, Coca-Cola, PepsiCo, Cadbury Schweppes, or Mars, that buy sugar in large quantities could also make a big difference if they would shoulder the full responsibility for the sugar they put in their products.
A decision from these companies that they would only buy sugar that does not ‘rot’ the environment could provide the turning point in making this ubiquitous commodity sweet for nature, as well as our taste buds. * Richard Holland is Policy Advisor at WWF's global Freshwater Programme. [i]
“The Environmental Impacts of Sugar Production”, Oliver. D Cheesman, CABI Bioscience and WWF (published in November 2004 and can be ordered from: http://www.cabi-publishing.org/Bookshop/NewTitles.asp