AND THE ENVIRONMENT

Encouraging Better ManagementPractices in sugar production

Young boy fishing in a traditional dug-out

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Contents

Introduction

Environmental impactsField level impactsFarm level impactsLandscape level impacts

Main causes of the impactsHabitat clearanceOveruse of waterIntensive use of chemicalsDischarge of mill effluentsPre-harvest cane burning

Better Management Practices to reduce the impactsEfficient irrigation systemsRational chemical useBiological control and Integrated Pest ManagementMaintenance of soil health and prevention of soil erosionModified tillageCover-cropping, terracing and strip planting in cane cultivationPhysical and live barriers in beet cultivationMaintaining beet in rotationReducing pollution from sugar millsFarm and landscape planningProtecting natural habitats in sugar monoculture beltsUse of by-products and alcohol production

Encouraging the use of Better Management Practices

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AND THE ENVIRONMENT

Encouraging Better ManagementPractices in sugar production

The cultivation and processing of sugarproduce environmental impacts through theloss of natural habitats, intensive use ofwater, heavy use of agro-chemicals,discharge and runoff of polluted effluent andair pollution. This leads to the degradationof wildlife, soil, air and water where sugar isproduced and of downstream ecosystems.

Although many of the environmental impactsof cane and beet cultivation are generic toagriculture, some impacts are distinct,particularly in their severity. Impacts relatingto irrigation of sugar cane and pollution runoffare of particular concern.

To evaluate the issues concerning thesustainability of sugar, CABI-Bioscience andWWF carried out a review of theenvironmental impacts of sugar. This briefingpaper draws on the CABI-WWF study, aswell as other sources (see: FurtherInformation, page 34).

The adoption of Better ManagementPractices (BMPs) requires support at severallevels. This includes changes to national andinternational policies, investment inappropriate irrigation infrastructure, and astronger sustainability commitment from thesugar and food industries.

Sustainability does not necessarily meanreduced productivity or profits; indeedmeasures needed to reduce environmentalimpacts will often also provide economicbenefits for farmers and mills. This providesan opportunity to reconcile environmentaland social needs with the long-termdevelopment of the sugar industry.

WWF considers that concerted actionis required among all stakeholders insugar production if a more sustainablefuture is to be guaranteed for thisubiquitous product.

Introduction

More than 145 million tonnes of sugar (sucrose)is produced per year in about 120 countries;open pan (artisanal) sugar production in Asiaprobably adds more than ten million tonnes tothis total. Annual consumption is expandingeach year by about two million tonnes. Around60-70 percent is produced from sugar canewith the remainder from sugar beet.

This paper highlights:

The environmentalimpacts of sugarproduction.

Farming and processingpractices that cause theimpacts.

Better ManagementPractices that can be usedto reduce these impactsto acceptable levels.

4

Estimates of soil lossesfrom wind-generatederosion under sugar beetrange from 13 to 49tons/acre/year in the USA.

Three million tonnes ofsoil is lost per year frombeet farms in the EU and1.2 million tonnes per yearin Turkey alone. It isestimated to cost theEuropean the industry £40million to separate the soilfrom the crop.

An estimated 5-6 million hectares of croplandis lost annually due to severe soil erosionand degradation. Soil is a living, dynamicresource, made up of different sized mineralparticles (sand, silt and clay), organic matterand a diverse community of living organisms.Different soil types display different properties,including vulnerability to erosion, salinisation,acidity and alkalinity. Cultivation of sugarcrops can contribute to soil degradationimpacting on soil quantity (by increased ratesof erosion and soil removal at harvest) andsoil quality.

Soil erosionErosion is a significant issue in areas undersugar cane or beet cultivation, particularlyin tropical areas (where most cane is grown),since erosion rates in tropical agro-ecosystems are usually greater than the rateof soil formation. The physical loss of soil byerosion is influenced by a range of factorsincluding rainfall and irrigation, wind,temperature, soil type, cultivation disturbanceand topography.

Economic and environmental aspectsof soil erosionIn agronomic terms, the loss of soil by erosionis a major problem that can affect futureyields and ultimately limit the sustainabilityof sugar cultivation by redistributing orremoving soil organic matter and nutrient-rich material. Soil erosion also represents asubstantial environmental threat from thewashing of sediments, which are oftenpolluted, into rivers, estuaries, and marineecosystems.

Environmental impacts

Sugar cultivation and processing impacts onbiodiversity and ecosystem services at the field,farm and wider landscape levels.

Field level impacts

Water-generated soil erosionWhere irrigation application is inefficient orrainfall is high, water withdrawal is generallycoupled with the loss of valuable soil fromthe farm. Worldwide estimates of soil lossesto water erosion under sugar cane rangefrom around 15 to over 500t/ha/yr.

Wind-generated soil erosionBeet fields in particular are vulnerable towind erosion as well as water erosion, sincethey are often left bare over winter.

Soil loss at harvestSoil losses during harvesting, particularly ofbeet, are cause for concern; 10-30 percentof the total beet harvest weight is soil (tare)(3-5 percent with cane).

Gully erosion due to location of a farm

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Cultivation on slopes

Sugarcane is currently grown on many steepslopes and hillsides, leading to high rates of soilerosion resulting from the increased rates ofwater runoff on sloping land. It is recommendedthat cane should not be grown on slopes greaterthan eight percent, although slopes of 20-30percent are planted, for example, in parts of theCaribbean and South Africa.

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6An example of where cane is grown

on a steep slope in South Africa.

Soil compactionA particularly significant impact of cultivationon soil physical characteristics is compactionresulting from a loss of soil structure. Heavyinfield transport machinery is most commonlyassociated with soil compaction problems.Loam-rich soils are more vulnerable tocompaction than clays or sands, andcompaction risk increases with soil moisturecontent.

Soil compaction increases bulk density andsoil strength, restricting the rooting ability ofthe crop, and decreases porosity and waterinfiltration rate, which can negatively affectthe soil mesofauna. Soil compaction mayparticularly affect invertebrates in the upperstrata of the soil, and it is in this zone wherenumbers of certain invertebrates is greatest.Increased rates of surface water runoff dueto reduced infiltration can also alter peakflow leading to flooding events.

TillageAlthough zero tillage farming can promotecompaction in heavy soils, since the soil isnot regularly loosened, conventional tillagecommonly promotes erosion by exposingsoil aggregates to rainfall. Conventional tillagei.e. deep ploughing, also drastically changessoil structure and is probably one of themost disturbing agricultural practices for soilfauna. In addition, tillage in both cane andbeet cultivation systems has been found topromote organic matter breakdown leadingto declines in soil structure and health.

Surface sealingSurface sealing and crust formation canoccur on heavily compacted cane growingsoils, resulting in a relatively impermeablelayer at the soil surface. Sodic soils areparticularly vulnerable to sealing, and theloss of organic matter, often associated withcultivation, can also render soils moresusceptible to sealing. Sealing reduces waterinfiltration and increases runoff, enhancingthe risk of erosion and pollution of waterways,as well as reducing the water available tothe crop and inhibiting seedling emergence.

Soil salinisationSalinisation of soils is a problem thatprincipally affects cane growers rather thanbeet growers and typically results from over-irrigation, inadequate drainage and cultivationin a flood plain or where sea water intrusionoccurs. Salinity of soils has been linked toserious cane yield declines.

Soil acidificationIncreased soil acidity affects plant healthand crop yield in some parts of the world.Acidification is also more prevalent in canethan beet growing areas, largely due to theuse of inorganic nitrogenous fertilisers suchas urea and ammonium sulphate. Underhigh rainfall conditions nitrate leachingoccurs, which also promotes acidification.

Soil organic carbon declinedby about 40% between 1979and 1996 in cane cultivationareas in Papua New Guinea,impacting on soil fertility.

Sugar cane yields inPakistan on soils affected bywater logging and salinity areup to 50% lower than onunaffected land. An estimated40% of the cane growing areasof Pakistan have salinityproblems.

Soil health includes a wide range of biological,chemical and physical variables, but can bebroadly defined as the sustained capability of asoil to accept, store and recycle nutrients andwater, maintain economic yields and maintainenvironmental quality. A healthy soil is estimatedto contain 1000kg/ha earthworms, 2700kg/hafungi, 1700kg/ha bacteria, 150kg/ha protozoaand 1000kg/ha arthropods and other smallanimals. Combined impacts can lead to a lossof soil fertility, a particular risk under cane, whichis generally grown as a continuous monoculture.

Impacts on soil health

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Farm level impacts

The suite of micro-organisms associatedwith a crop is often overlooked, although itplays such a critical role in ecosystemfunction, for example in the turnover of soilorganic matter. Most intensively cultivatedagro-ecosystems are relatively lacking inbiodiversity.

With the possible exception of birds,vertebrates present in cane fields are oftenregarded as pest species and subject tocontrol, yet many may be beneficial as naturalenemies of weeds and pests. Weeds andpests may also provide important resourcesfor other (non-pest) wildlife which play animportant role in the food chain and thushealth of the agro-ecosystem.

Landscape level impacts

Impacts of sugar cultivation on downstreamecosystems: Agriculture is arguably thepredominant influence on the Earth’s landsurface and undoubtedly represents themain cause of wetland habitat loss. Thisoccurs through the runoff of polluted effluentinto water courses, due to the heavyabstraction of freshwater resources upstreamof wetlands habitats, or by altering the naturalflow regime.

The impacts felt downstream are thecumulative result of a complex set of landand water use decisions in a river basin.Within this context, cane or beet can playan important role in some sugar producingcountries.

The sugar industry in Australia has been a significant playerin major infrastructural projects, including damming of theBurdekin, Tully and Barron Rivers, which has altered thepattern of freshwater flow into the Great Barrier Reef lagoon.Cane growing has shown to increase sediment and nutrientloads, particularly following heavy rainfall, which can carrythese materials into the sea, reducing water quality andimpacting on inshore reefs. The sediment export rate in thelower South Johnstone River has been estimated at 180,000tonnes of fine sediment/year, with sugar cane farmingcontributing to these sediment loads.

Agricultural systems, or ‘agro-ecosystems’,represent interacting systems of biotic (living)and abiotic (non-living) components thattogether form a functional unit. Agro-biodiversityis the diversity related to the agro-ecosystemand encompasses the variety and variabilityof plants, animals and micro-organisms thatare necessary to sustain the key functions andprocesses of the agro-ecosystem and supportthe production of food.

Control of froghopper(Aeneolamia flavilatera) pestpopulations in Guyana withinsecticide was unsuccessfuland withdrawal of insecticideapplication resulted in controlof the froghopper due torecovery of a froghopperpredator which was vulnerableto insecticide use.

Vanishing Carsamba River in the sugar beet belt

of the Konya Basin, Turkey.

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Cane producing areas in KwaZulu-Natal, South Africa,are mainly situated in the catchment areas of gently to steeplyundulating land from which runoff flows into the major rivers ofthe KwaZulu-Natal seaboard, including the St Lucia WorldHeritage Site. A lack of adequate integrated soil conservationpractices on some farms has been linked to soil erosion, leadingto degradation of the rivers and estuaries.

Phosphorus-rich runoff from sugar cane fields in Florida isheld largely responsible for the decline of the Everglades. TheEverglades is a naturally nutrient-poor wetland where sawgrassthrived because naturally low levels of phosphorous inhibitedthe growth of more aggressive species, such as cattails. However,the common practice of spreading phosphorus on the canefields in the Everglades first caused the sawgrass to growabnormally large before dying back to give way to cattails, whichhave now spread across more than 50,000ha of conservationareas, crowding out willow and bay and excluding fish.

Sugar beet irrigation in Andalucia, Spain, is contributingto lowered water levels in rivers such as the Guadalquivir, limitingthe water reaching important wetlands during the summer.These wetlands include Doñana, where many bird species relyon a healthy habitat (griffon vulture, booted eagle, red and blackkites, short-toed eagle, Baillon's crake, purple gallinule, greatspotted cuckoo, scops owl, red necked nightjar, bee eater,hoopoe, calandra, short-toed and thekla larks, golden oriole,azure winged magpie, Cetti's and Savi's warblers, tawny pipit,great grey shrike, woodchat shrike and serin).

Over the last 60 years the construction of dams, barragesand irrigation systems in Pakistan have lead to a 90 percentreduction in the amount of freshwater reaching the Indus Delta.Sugarcane cultivation is consuming significantly more waterper unit area than any other crop grown in the Indus Basin.The Delta supports the world’s largest expanse of arid landmangroves, which rely on an inflow of freshwater. Of the 260,000hectares of mangrove forest recorded in 1997, only an estimated65 percent remains and is dominated by just one salt-tolerantspecies. The endangered Blind River Dolphin (Platanista minor),found throughout the Indus and its tributaries 100 years ago,now exists in six totally isolated sub-populations.

Removal of riparian vegetation and

drainage in a valley bottom.

Discussing decreasing ground-water levels

on a beet farm in Spain.

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The mangroves in the IndusDelta provide an excellentnursery for young fish andshrimp, upon which manylivelihoods depend. Shrimp area major export commodity,

making up 68 percent of the US$100 million that Pakistan earnsin foreign exchange from fish exports. Abstraction of water forirrigation (wheat, rice, sugar and cotton), coupled with drought,has meant that about 80 percent of the five million people whoonce earned a living from fishing or river boat work in Pakistanhave left in search of work in slums of Karachi.

Impacts of sugar cultivation ondownstream livelihoodsAgriculture, including irrigated canecultivation, not only threatens the biodiversityof natural wetlands, but can also threatenthe traditional cultures and livelihoods ofcommunities that rely upon them.

Impacts of sugar and by-productprocessing on downstream ecosystemsDischarge of effluents from sugar mills andfrom processing by-products (e.g. molasses)has been shown to result in the suffocationof freshwater biodiversity, particularly intropical rivers that are already naturally lowin oxygen.

The pollution of Danish coastal waters by sugar factoryeffluent has been linked to the occurrence of bacterial pathogensand an ulcer syndrome in the cod Gadus morhua.

In Cuba the oxygen deficiency in rivers from discharge ofsugar factory waste water (amongst other activities) led todominance of aquatic macrophytes, resulting in thick mats ofweeds that impeded the water delivery capacity of canals andaffected sport fishing and tourism.

In 1995, the annualcleaning of sugar mills inthe Santa Cruz region ofBolivia resulted in thedeath of millions of fish inlocal rivers. ©

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A programme to use sugarcane as the raw material forfuel alcohol production led to the deforestation of new areasin the State of Alagoas, Brazil, such that only three percentof the original rain forest cover remains.

Recent studies have also shown an 85 percent reductionin Brazilian Cerrado vegetation in the regions of Franca,Araraquara, Ribeirao Preto and Sao Carlos due in part toclearance for sugar cane cultivation.

There are plans to increase the area under sugar cane inthe Indian Punjab from 80,000 to 136,000ha.

Main causes of the impacts

Habitat clearance

Habitat destruction for cane cultivationThe production of sugarcane has probablycaused a greater loss of biodiversity on theplanet that any other single crop. Fifteencountries around the world devote betweenten and 50 percent of their land area to canecultivation and in seven countries sugarcanecovers more than 50 percent of the land.Substantial areas of biodiversity-rich habitathave been cleared for cane cultivation, suchas tropical rain forest and tropical seasonalforest. Land clearance not only results in thedirect loss of species and habitats, butunderlies a range of wider impacts onecosystem function, including changes tohydrology and increased soil erosion.

Recent land clearance forcane cultivationAlthough the greatest land clearance forsugar cane cultivation is historic, the areaunder cultivation in some areas hascontinued to expand in recent years.

Wetland habitat lossHalf of the world’s wetlands have been lostto drainage and conversion to agriculture(70-90 percent in Europe and USA), andeven protected wetland areas are subjectto agricultural impacts. Low-lying and alluvialareas in particular have typically beenreclaimed and drained for sugar canecultivation, as they often support the richestsoils and enjoy a good natural water supply.

Habitat destruction for beet cultivationSubstantially smaller areas have been clearedspecifically for sugar beet, as the crop hasonly been cultivated relatively recently andin many cases has been grown on land thatwas already under some other form ofcultivation.

Large areas of theEverglades wetland habitathave been reclaimed for theexpansion of agriculture. Nearly200,000ha is under canecultivation, resulting in dramaticdeclines in biodiversity.In addition to habitat loss,ecosystem impacts includemajor redistribution of waterflows and subsidence due toshrinkage, compaction andaccelerated microbialdecomposition of drained soils.

Clearance of land for cane cultivation hasresulted in substantial loss of coastalwetlands in many cane growing areas ofAustralia:

A 60 percent reduction inwetland habitats occurred inthe Johnston River catchmentbetween 1951 and 1992.

In New South Wales, caneis often grown right up to thebanks of streams, leaving nonatural vegetation.

Around 45km of streambank vegetation was clearedin the Herbert River catchment,Queensland, between 1990and 1995.

Sugar cane planted in a floodplain,

Queensland, Australia.

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Thousands of hectares of new beet fields in Turkey

following development of a new irrigation scheme.

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Agricultural water useAgriculture is by far the biggest user of waterworldwide. Seventy percent of globalfreshwater withdrawals are for irrigation,rising to more than 90 percent in some aridcountries. Major irrigation projects have oftenbeen promoted for development reasons,yet returns have frequently been insufficientto service the capital debt or cover runningand maintenance costs. Planning has oftennot adequately addressed environmental orsocial needs, leading to impacts ondownstream ecosystems and livelihoods ofcommunities that rely on fisheries.

Sugar cane water useAlthough sugar cane is an efficient converterof biomass from water, it still needs about1500-2000mm/ha/year and ranks amonga group of crops noted for their significantwater consumption (along with rice andcotton). It is a deep-rooted crop, whichremains in the soil all year round and is ableto extract soil water to depths well belowone metre. In areas where sugar cane growthrelies on rainfall, the crop can influence riverflows as it intercepts run-off from thecatchment into rivers and taps into groundwater resources.

In the Indian state ofMaharashtra, sugar canecovers just three percentof the land yet cornersaround 60 percent of thestate irrigation supply andis a cause of substantialgroundwater withdrawals;the water table in placeshas dropped from 15metres to around 65metres in the past 20years.

Sugar beet water useAround one fifth of the world’s beet cultivationarea is irrigated. However, there are questionsover whether irrigation is actually necessaryin some of the areas where beet is grown,since: i) beet is not particularly sensitive towater availability; ii) the crop is principallygrown in temperate areas, where sunlightrather than water availability is the limitingfactor for plant growth; and iii) in Europe theeconomics of beet production are skewedby fixed quotas per country and highguaranteed prices which mean that sugarbeet is not grown in either the most suitedor least cost regions.

Irrigation inefficiencyThe principal irrigation systems available are:i) surface (flood / furrow)ii) overhead sprinklers(drag line / centre-pivot)iii) drip / trickle techniques.Drip and trickle techniques tend to be themost water-use efficient, but requiresignificant financial investment, while surfacetechniques are the least efficient, but arelow cost and do not require farm machinery.Due to poor management, in many areas ofthe world only an estimated 30-35 percentof the water withdrawn for farming reachesthe crop and the rest is lost from irrigationchannels by evaporation and through run-off from the field.

Water application insugarcane cultivation in theAmaravathy River Basin,India, was 28 percent higherthan the recommended levels.

In Mackay, Australia,irrigation of sugarcane hasresulted in additional runoff anddeep drainage, amounting to29 percent of the irrigationwater applied.

Over-irrigation and pollutionSince irrigation management is often veryinefficient, high water withdrawal is generallycoupled with the runoff of polluted irrigationwater containing sediment, pesticides andnutrients.

Water use in processingBoth beet and (to a lesser extent) canefactories use large amounts of water to washoff the considerable quantity of soil removedwith the roots at harvest.

Irrigation and human healthOver-irrigation or inefficient irrigation systemsthat leave water standing in fields canenhance the incidence of water-borneparasitic infections such as Bilharzia(schistosomiasis).

In the South Coast IrrigationSystem in Puerto Rico, theprevalence of Schistosomamansoni infection rose fromzero before 1910, to around25 percent by 1930 followingthe establishment of irrigationsystems for sugarcanecultivation.

The prevalence of S.mansoni infection in childrenat one camp in the Wonji sugarestate, Ethiopia, rose from 7.5percent in 1968 to 20 percentin 1988. Prior to irrigationdevelopment in the area boththe disease and the host snailwhere unknown in the area.

Overuse of water

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Use of ground-water resources to

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Transvaal, South Africa.

Water supply to sugar cane fields, Zambia.

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Pest controlIntensive agricultural food production ingeneral uses high levels of pesticides(herbicides, insecticides, fungicides,nematicides, rodenticides, plant regulators,defoliants or desiccants), with herbicidesrepresenting about 50 percent of pesticidesused in many countries. A wide variety ofpesticides are used in the cultivation of sugarcrops. Herbicide use in sugar beet is amongthe highest compared to other crops.

Impact of pesticides on crop yieldsLong-term agrochemical, microbiologicaland ecological experiments on the use ofpesticides on sugar beet in Russia havedemonstrated accumulation of toxicsubstances in roots and aerial parts of thecrop plants, resulting in retardation of growthand a decrease in sugar content whenmaximum doses were used. In canecultivation, a growth regulator, such asEthephon, or an herbicide, such asGlyphosate, is applied 45 days beforeburning to desiccate the plant. Whenharvesting is delayed, the yield loss can beas high as five percent due to the reductionof sugar content.

Overuse of fertilisersInorganic fertilisers typically supply nitrogen,phosphorus and/or potassium in mineralform. Environmental impacts generally arisebecause the nutrients in the fertilisers arenot entirely taken up by the crop but moveinto the environment. The overuse of fertiliserson cane or beet crops is typical of farmingin general.

Nitrogen (N) fertiliser use in the Australian sugarcaneindustry increased substantially in the post-war years, and formore than a decade, N fertiliser use was almost double thatrequired to produce the actual cane (and sugar) yields obtainedby the industry. In the Tully River catchment (North Queensland)alone, the area under sugarcane and bananas doubled and Nfertiliser use increased by 130 percent between 1987 and 1999.

Intensive use of chemicals

Increased application of N fertilisers in Australia hasled to acidification, contamination of ground and surfacewater and enhanced greenhouse gas emission.

Only 8-44 percent of fertiliser applied to rotation systemsincluding sugar beet in Europe was taken up by crop plantsdirectly (although around one third was incorporated in thesoil organic matter and remained available to plants overlong periods of time).

Research in Austria demonstrated that with conventionalrates of fertiliser application, only 50 percent of soil nitrogenwas taken up by the crop, 20 percent remained in the soil,and 30 percent was lost.

Sugar beet, Spain.

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Social impacts of pesticide useMany large-scale pesticide applications,including the spread of rodenticides, arecarried out using aircrafts.

The negative impacts of pesticide use onhuman health are considerable; the WHOestimates that there are 25 million cases ofacute chemical poisoning in developingcountries each year related to pesticide usein agriculture. Despite widespread concernover pesticide misuse, the total value ofworld sales has increased 2.5 times in thelast 20 years, to US$30 billion. 15

Pesticide stockpile, Nanguila, Mali.

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Discharge of mill effluents

Perhaps the most significant impact fromcane and beet processing is related topolluted effluent. In some countries withweak environmental laws, when sugar millsare annually cleaned, a tremendous amountof matter is released, which is usuallydischarged straight into streams. Cane milleffluents tend to be relatively rich in organicmatter compared to other sources, and thedecomposition of this matter reduces theoxygen levels in the water, affecting naturalbiochemical processes and the speciesinhabiting those freshwater systems. Potentialpollutants in these effluents include heavymetals, oil, grease and cleaning agents.

The production of alcohol from cane or beet can also resultin significant pollution as the by-product, known as ‘vinasse’,which is in some cases discharged into rivers. Every litre ofalcohol produced from sugarcane produces 13 litres of vinasse.

In the Gorakhpur districtof Nepal, discharge into astream of improperly treatedwater from two sugar factoriesand a distillery rendered thestream’s water unfit fordrinking, bathing or irrigation.

Steam and ash production from sugar cane processing.

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Oil residues, Colombia.

Cane arriving at mill, Mazambuka, Zambia.

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Cane delivery at mill, Pakistan.

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Air pollution: Substantially elevated levels of carbon monoxideand ozone in the atmosphere have been found around sugarcanefields in the state of Sao Paulo, Brazil, at the time of pre-harvestburning.

Soil degradation: There is evidence that sustained pre-harvestburning of sugar cane can contribute to a decrease in soilquality, by causing a decline in soil microbial activity and thephysical and chemical properties of the soil; pre-harvest burningmay be responsible for as much as 30 percent of the annualnitrogen removal in a cane crop

Loss in productivity: Cane burning can reduce the quality ofsugar recovered from the cane as well as reduce the quantityof cane retrieved by as much as five percent.

Pre-harvest cane burning In many sugar producing countries, the canefields are burnt immediately before harvestingfor easier cutting, post harvest cultivationand pest control. ‘Green cane’ harvesting(without burning) is also practiced. Althoughit has some benefits, as noted above, pre-harvest burning leads to:

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Burning cane in Stalta, Argentina.

Cane burning through a wetland, South Africa.

Better Management Practicesto reduce the impacts

Sustainability in the sugar industry does notnecessarily imply reduced productivity and profits;indeed, measures to address environmentalimpacts can provide economic benefits forfarmers or mills through cost savings from moreefficient resource use.

This provides an opportunity to reconcilethe needs of the environment and peoplewith the long-term development of the sugarindustry. Better Management Practices(BMPs) do just this, addressing environmentalconcerns such as habitat loss, water overuseand pollution; social needs such as availabilityof clean water for drinking and sanitation;and economic considerations such as cropyield and maintenance of long-term soilhealth.

There are a range of BMPs in use or underdevelopment that tackle the mainenvironmental and social impacts of sugargrowing and processing as summarised onthe following pages.

Waterfall, East Sepik,

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In Swaziland, water application efficiencies for sugarcane have been estimated to be 72-89 percent under dripand centre pivot systems, 49-88 percent under dragline,and 48-75 percent under furrow irrigation.

Efficient irrigation systems

The effectiveness of irrigation strategies canbe assessed by an analysis of Water UseEfficiency (WUE): the ratio of crop yield towater consumed by the crop. Drip irrigationsystems, which deliver water to the cropplant (surface drip) or root zone (sub-surfacedrip), are generally the most water efficient,followed by centre-pivot systems, othersprinkler systems, furrow irrigation, and finallyflood irrigation.

The key to improving water productivity isto match the irrigation system to the soiltype, climate, farm management andaffordability.

Larger-scale farmers are able toimplement advanced commercial drip,sprinkler, or centre-pivot systems whilesmall-scale farms, and even some largeestates, mainly use inefficient floodirrigation. Low-cost drip systems areavailable for small-holders, provided thatmicro-credit is available for purchase ofthe equipment and sufficient ongoingtechnical support is provided. Furrowirrigation only requires a ridger to cut thefurrows and with alternate furrow irrigationsubstantial water savings can be made:

Increased water use efficiencyOne of the main benefits of implementingbetter irrigation systems is increased wateruse efficiency, meaning that more water isavailable for other needs, such as those ofthe environment or communities; newinstitutional mechanisms may be requiredto share out water saved in an equitablemanner.

In Pune, India, water savings in cane fields of 36 percenthave been achieved by flooding alternate (rather than all)furrows.

Alternate furrow irrigation in beet fields in Iran at six dayintervals used 23 percent less water than irrigation in everyfurrow at ten day intervals, maintaining yields and increasingwater use efficiency by 43 percent.

Skip-furrow irrigation for increased water use

efficiency on small scale farms, Pakistan.

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Increases in water useefficiency of 43-66 percenthave been achieved in TamilNadu, India, by using alternatefurrow irrigation in cane fields,with the greatest increasesattained in combination withtrash mulching.

Studies in Pune, India,found that the use of a canetrash mulch enhanced watersavings gained with dripirrigation by a further 16percent.

Improved irrigation techniques can also becombined with trash mulching for furtherwater savings:

Farmers in Pakistan discussing

Better Management Practices

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Drip irrigation and centre pivot irrigation.

The two most efficient irrigation systems.

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Severe water restrictionsin Zimbabwe led to arevised system ofscheduling for sugar caneirrigation that provided apotential saving in wateruse of 32 percent whencompared withconventional practices,without reducing the sugaryield.

A report from Mexicoasserts that waterconsumption can bereduced by 94 percentwith production lossesbelow ten percent whenwater-recycling isimplemented.

Irrigation scheduling, including the use oftensiometres to monitor soil moisture, andtail-water recycling (where water-runoff fromfield is collected and reused for irrigation)are also ways of improving irrigationmanagement:

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Three or four peasant familiesjoin forces to process sugarcane in local factories as analternative to its commercialproduction. All the familyparticipates in the process toget brown sugar from sugarcanes. La Planada hasdeveloped some research oversustainable use of sugar cane,aiming at a minor impact onthe natural resources.

La Planada Natural Reserve, Colombia.

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Decreased fertiliser and pesticiderequirements with drip irrigationDrip fertigation is the application of fertiliserthrough the drip system, delivering nutrientsonly to the plant base (surface drip) or rootzone (sub-surface drip). Drip fertigation is ofparticular interest from an environmentalperspective as it combines the increasedwater use efficiency of a drip irrigation systemwith the potential to manage fertiliserapplications more effectively and therebyreduce fertiliser use.

In addition, the application of soil pesticidescan be reduced by 30 percent when applieddirectly to the root zone. By using dripirrigation, a farmer can use the least toxicpesticide at or below recommendeddosages.

Increased agronomic benefits of WaterUse EfficiencyEnhancing water use efficiency not onlybenefits the environment, but provides arange of financial benefits to the farmerincluding reduced water and/or electricitycosts and yield increases:

Modification of furrowshape with alternate furrowirrigation in Burdekin,Australia, reduced wateruse in cane fieldsthroughout the season by45 percent, representing asaving of $218/ha/yr to thegrower and a potentialsaving of $1.74 millionannually to the Burdekinsugar industry.

In Maharashtra, India,the government provided asubsidy for the installationof drip irrigation. The costwas Rs36,423 per farm,providing a yield increaseover surface irrigation of24.32 tonnes, equating toRs13,989 per year. Thiswould provide a return oninvestment within threeyears.

In the Simunye sugar estate in Swaziland the cost ofconversion to a subsurface drip system for sugar canecultivation was US$2542/ha, versus US$868/ha to retainthe sprinkler system and replace worn-out parts. Benefitsfrom the new system equated to US$472/ha/yr in terms oflabour cost savings, increased sucrose yields and watersavings, providing a financial benefit within two years.

An agro-economicanalysis of drip irrigationfor sugar beet productionin Wyoming, USA,concluded that economicreturns from drip were 11percent greater than withfurrow irrigation.

Yields with drip irrigationhave been shown toincrease by around 20percent in Thailand andIndia.

Studies from Mauritiusand Australia suggest thatdrip fertigation allows Nfertiliser inputs to bereduced by 25-50 percentwithout impairing caneproductivity.

Drip irrigation for sugar beet

production, Swaziland.

Ox drawn furrow ridger.

The tube allows efficient application of

fertiliser reducing cost and nutrient run-off.

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Reduced fertiliser useIn many areas of the world, nitrogenousfertilisers are routinely applied in sugar canecultivation at rates of around50-200kg/ha/year, contributing (amongstother things) to the process of soilacidification. There is a direct economicincentive for farmers to reduce fertiliser inputs,as these represents significant costs andover-use of N fertiliser reduces sugar yield.Many sugar industries have consequentlypublished recommendations on fertiliser useand incorporate these in guidance providedto their farmers.

Approaches for reducing fertiliser use in canecultivation systems include a more site-specific assessment of fertiliser requirements,cultivation of leguminous green manure cropsduring fallow periods or in rotation, the useof biofertilisers (combinations of nitrogen-fixing micro-organisms and organicamendments), green cane harvesting andpress mud, a sugar cane mill by-productwhich is particularly effective for reducingphosphorus deficiency in cane.

Crop logging, used to monitor plant weightand leaf nutrient content can be used insugar cane cultivation to assess the foliarnutrient levels and adjust the fertiliser rateor other elements only if needed.

Aside from producing sugar, sugar beet’srole as a break crop in arable rotations cancontribute to a reduction in pesticide andfertiliser inputs during other phases of therotation, by interrupting a potential build upin pests and diseases associated with othercrops, and by contributing organic matterto the soil in the form of root fragments, leafmaterial and/or beet tops ploughed infollowing harvest. However, fertiliser inputsfor beet cultivation are still significant:

A 50 percent reductionin total nitrate inputs tobeet fields in the UK wouldresult in yield reductions ofonly some ten percent.

Rational chemical use

The use of biofertiliser in place of chemical fertilisers, couldreduce inorganic fertiliser requirements by 20-25 percent andreduce the risk of nitrate leaching.

Press mud biofertiliser: a phosphorous rich by-

product from sugarcane mills that can help

overcome phosphorus deficiencies which are

common in countries such as Pakistan & India.

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Restrained chemical use Although the control of pests in sugar andbeet cultivation has relied heavily oninsecticide use, there is an increasing movetowards reduced use:

The Indiscriminate use of pesticides creates a number ofproblems, such as development of resistance in pests, upsurgeof secondary pests because of elimination of natural enemies,pollution of the environment making it hazardous for humanbeings and animals and moreover, they are expensive andincrease the cost of crop production.

Pakistan Agricultural Research Council

Over 70 percent of Queensland cane growers havecompleted a voluntary one-day course and have been accreditedin the use of farm chemicals, resulting in a marked increase inproficient use and reduced application rates and frequencies.

Between 1982 and 1998, the total insecticide input to UKbeet cultivation fell from around 11kg/ha to just over 5kg/hadue to a shift away from spraying towards seed treatment.The use of nematicides (seen as the most toxic group ofagrochemicals) fell by around 50 percent between 1994 and2000.

In sugar beet fields in the Irish Republic, plots where weedswere allowed to grow, compared to plots treated with herbicides,supported greater numbers of soil Collembola, enhancednumbers and diversity of ground-dwelling arthropods, and hadconsiderably smaller numbers of the pest aphid Aphis fabae.

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Weevil, Peru.

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Populations of a cane weevilparasite in Hawaii wereenhanced where field marginscontained plants that could actas nectar sources. Continuouselimination of such plants withherbicides resulted in adecrease in populations of theparasite, compromising its roleas a biological control agentagainst the weevil.

Biological control andIntegrated Pest Management

In some parts of the cane growing world,there is a greater emphasis on non-chemicalcontrol methods, particularly for insect pests.There are numerous examples of successfulIntegrated Pest Management (IPM)programmes in sugarcane. IPM combinesbiological control with a variety of otherappropriate physical, chemical andmechanical control methods to achieve amore holistic and sustainable approach topest control.

Papua New Guinea is considered to be the centre of originof sugarcane. The sugar industry there is consequently moreafflicted by pests, diseases and weeds, most of which are nativeand may have co-evolved with the ancestors of the crop.Control of the stem boring larvae of the of the noctuid moth(Sesamia grisescens) is based on a sound knowledge of thebiology of the pest species and included identification of resistantcultivars and optimum planting times, rational pesticide use,biological control, close monitoring of the situation in the cropand the use of pheromones for trapping or mating disruption.

Sprinkler irrigation, Africa.

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Discussing sugar beet disease

occurrence, California.

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The shift from pre-harvest cane burning to‘green cane harvesting’ (where the cane isharvested without being burned first) and‘trash-blanketing’ (where the cane leavesare cut from the plant and left on the soil asa mulch while the stalks are taken away forprocessing) provides a range ofenvironmental benefits. Any disadvantagesof these methods to the farmer (increased

harvesting costs, complications in irrigationand fertiliser application, slowing of tilleremergence) appear to be significantlyoutweighed by the benefits (elimination ofaerial pollution and direct burning impactson soil, improved soil and water conservation,enhancement of soil organic matter, weedsuppression and increased yields).

The white grub (Phylophaga sp.) pest which feeds on theroots and causes severe losses in cane production is typicallycontrolled using high quantities of the chemical Ethroprop.However a fungus (Beauveria bassiana) which feeds on grub’slarvae, can be used efficiently to control the pest. In addition,white grub adults can be caught by the use of night-illuminatedtraps during larvae production. Since 70 percent of adults arefemales and each female produces an average of 35 eggseach, the control method is very efficient.

Valuable lessons can be learned about theimpact of pesticides on non-target specieswhich may be of benefit as natural predatorsof pests:

Populations of thefroghopper pest in canecultivation in Guyana declinedto low levels after attempts atchemical control werediscontinued, even without therelease of specific biologicalcontrol agents. This reductionin pest numbers was due tothe recovery of existing naturalenemy populations followingthe withdrawal of insecticidetreatment.

Maintenance of soil health andprevention of soil erosion

Sustainable systems of cane and beetcultivation that maintain or improve soil qualityare required not only to mitigateenvironmental and social impacts but toensure the future of the sugar industry.A wide range of measures has beenproposed and investigated for the reductionof soil erosion and improvement in soil qualityin sugar cane and beet cultivation systems.These measures include trash mulching incane cultivation, maintenance of beet aspart of a crop rotation, terracing, contourand strip planting of cane on slopes,maintenance of ‘live barriers’ (hedgerows,riparian zones), and modified (reduced orminimum) tillage.

Trash blanket mulching incane cultivation

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Trash mulching, La La Planada Natural Reserve, Colombia.

Increased soil fertilityRetention of a cane trash blanket canresult in up to 10-20 t/ha of organic matterfrom the cane leaves that is left on thesoil surface after harvest. This has beenshown to increase microbial biomass,carbon (C) and basal respiration in thesurface soil and also to enhance the sizeof the earthworm community. In the longterm trash blanketing can be expectedto raise soil organic matter content byaround 40 percent after 60-70 years.

In recent years there has been a shift away frompre-harvest burning towards green caneharvesting and trash blanketing.

In 1997, 65 percent ofQueensland cane washarvested green, comparedwith just 18 percent in 1987.

Reduced water erosionTrash mulching is particularly recommendedon slopes greater than 15 percent to reducethe impact of raindrop action and soil erosionduring the wet season, especially if insufficientcrop cover has developed.

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In Lucknow, India, trash mulching was shown to improvesoil organic C by 0.13 percent, available N by 37 kg/ha andavailable P by 10 kg/ha. Conversely, burning of trash reducedorganic C by 0.02 percent, available N by 15 kg/ha andavailable P by 16 kg/ha.

Modified tillage

Prevention of soil erosionIn South Africa, minimum tillage is advisedon slopes greater than 11 percent on erodiblesoils, 13 percent on moderately erodiblesoils, and 16 percent on erosion-resistantsoils. Whilst conventional tillage is acceptableon slopes with shallower gradients, ploughingshould be carried out across the slope, andshould be discontinued with the onset ofhigh-intensity rains.

Zero tillage reduced soil lossrates on slopes of 5-18 percentin Australia, from 148t/ha/year(conventionally cultivated) to<15t/ha/year.

In Mauritius, minimumtillage caused no loss in yieldover a complete cane cycle offive years or more, protectedthe soil structure, and resultedin better weed control (with theexception of heavy soils).

Use of reduced tillagesystems reduced soil lossesfrom 49, 19.5 and 13.1ton/ac/yr to 17, 5.5 and 13.1ton/ac/yr, respectively, in athree year experiment inWyoming, USA.

Cover-cropping, terracing andstrip planting in canecultivation

Prevention of water erosionCompared with other arable systems, sugarcane can represent a relatively effective covercrop as the crop tends to remain in theground for a number of years producing anextensive root system and a closed canopythat protects the soil from the erosive effectsof rain.

However, on sloping land the risk of soilerosion is still high. Farmers could benefitby taking these areas out of production andreplanting with tree crops, provided rainfallfor the area is sufficient. This will improvewater retention and provide a more gradualwater release. Where land is kept in canecultivation, cane terracing (where a soil lipis built at the edge of each terrace) of slopesis recommended - the steeper the slope,the narrower terraces and cane rows shouldbe aligned at right angles to the slope.To further prevent soil erosion on slopes, thepractice of cane strip planting isrecommended. Under this practice, stripsof cane rows at different stages ofdevelopment are established in adjacentterraces. Mature and maturing strips providebarriers against erosion from the relativelybare strips (those with cane at the earlieststages of development, or where harvestinghas just occurred). Strip planting is advisedon all slopes greater than two percent.

Cane terracing showing the soil lips built

at the edge of each terrace to prevent

soil erosion, South Africa.

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Building terraces on sugarcane fields to

prevent soil eroision, South Africa

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Reduced wind erosionThe creation of ridges and live barriers inbeet fields can help to reduce the impactsof wind erosion, which causes damage tosugar beet seedlings as well as loss of soil,thus affecting beet yields.

In the UK, beet yieldsincreased from 8-10 to 15-17ton/ac when ridges werecreated between rows of beetto reduce wind erosion.

A single-row shelterbelt ofcoppiced trees significantlyreduced wind erosion on beetfields during a dust storm withhigh winds in Poland. Theestimated yield of sugar beeton the protected area was 32percent greater than thatobtained by re-sowingunprotected areas after thestorm.

The use of Lucerne as acover crop in beet rotationreduced erosion by around 33percent in comparison witharable crops (maize, wheat).Lucerne cover reduced run-offby around 50 percent.

Physical and live barriers inbeet cultivation

Beet in rotation, Spain.

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Trials in Poland of sugar beet grown continuously for 6-25 years or in rotation with spring barley, winter rape, winterwheat and Vicia faba showed greater yields when grown inrotation; root and leaf yields averaged 44.6 and 46.5 t/ha,respectively, in rotation and 30.9 and 27.4 t in continuouscultivation. White sugar yields were 7.5 and 5.11 t in rotationand monoculture, respectively.

Maintaining beet in rotation

Maintained soil fertilitySoils in continuous arable production (evenwith rotation of crops) remain at risk ofdegradation and thus crop rotations areimportant both for the farm's short termresults and for maintaining long term soilfertility.

Sugar mills can be sited downwind ofpopulated centres to minimise nuisance fromgaseous emissions and isolated from naturalecosystems to minimise the impacts ofeffluent discharge on rivers and coastalareas.

Reducing fly ash productionBagasse can be dried prior to its use asboiler fuel, which increases the efficiency ofburning and reduces emissions. Basic dustcontrol measures are cheap and simpletoinstall in most cases.

Reduced gas and odour productionHydrogen peroxide in place of sulphurdioxide in sugar mills has been shown toreduce air pollution and resulted in a higherquality white sugar product while requiringno new equipment.

Various odour control measures are availablein the management of sugar beet factorywastes, such as the use of enzymes andorganic scavengers for control of H2S.

Reducing effluent dischargeA range of techniques is available for treatingsugar mill effluents, including the treatmentof mill sludge with micro-organisms thataccelerate the rate of decomposition.

Treatment in an openfermentation chamberdecreased wastewater CODby 82 percent in three days ina Polish sugar beet factory.

Zero pollution has beenachieved in some Indian sugarmills by totally recycling treatedeffluents as make-up water forcooling towers and sprayponds.

Reducing pollution fromsugar mills

Modifying the combustionprocess and adoptingemissions-control systems in aColombian cane mill reducedconcentrations of particulatematter by about 98 percent.

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In Poland the numberand diversity of insects weregreater on the boundary ofsugar beet fields than inadjacent fields. In particular,predatory carabids andhoverflies, and parasiticHymenoptera, predominatedin the field margin.

Farm and landscape planning

Riparian vegetationNatural riparian vegetation plays a particularlyimportant ecological role, providing habitatfor wildlife, and influencing water quality andtemperature, stream morphology, andecosystem dynamics. It can also provide abuffer between agricultural systems andwaterways. The planting and maintenanceof indigenous vegetation in riparian habitatscan reduce sediment loads andagrochemical concentrations in watersrunning off from cane fields. Bundles of canetops are also recommended for liningwaterways until protective native vegetationbecomes established.

Field marginsThe characteristics of field margins andadjacent land parcels are also importantinfluences on biodiversity and abundancein cultivation systems.

Beet diversity in rotationSugar beet is typically grown as part of acrop rotation, and is therefore (to someextent) already part of a diversified systemof agriculture which has environmentalbenefits over less diverse systems.

Financial benefitsThere are also agronomic advantages inmaintaining diversity within the standing cropitself; domination of large cane growing areasby single varieties in Australia has led toserious problems with disease outbreaks.

In South Africa, the establishment of a farm land use planis generally carried out in steps, over a period of up to ten years.Knowledge of the types and characteristics of soils is veryimportant as soil characteristics have a major influence onrequirements for irrigation, drainage, nutritional managementand variety. The plan includes the correct layout of fields, roads,soil conservation structures and waterways. This allowsenvironmental assessments, regular environmental audits andthe collection of baseline data and monitoring to be carried out. Uncultivated areas of the farm should be mapped (accordingto a recognised habitat classification system) as part of thedevelopment of a management plan.

Natural habitats within the farm landscape requireappropriate planning and management, includingthe restoration of degraded land to provide wildlifecorridors and maintenance of watercourses.Farm and landscape plans, of all sorts frominformal agreements to highly technicaldocuments, provide a mechanism to gainproductivity and to reduce impacts.

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Discussing farm land use plans, KwaZulu-Natal, South Africa.

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Fragments of natural habitats that persistwithin the agricultural landscape canrepresent important refugia for indigenousbiodiversity.

However, questions generally arise overconservation management strategies wheresmall patches of natural habitat survive inagricultural landscapes. For example,although approximately 19 percent of the11,200km2 of Terai grassland in northernIndia is now included in Protected Areas(PAs), the PAs are situated within a landscapeof forests, sugar cane and paddy fields,

scattered hamlets, and small townships.Wildlife management plans typically addressthe PAs alone or just the forest management,whereas an integrated landscape approach,encompassing all elements of land use in aholistic manner, is required if the ecologicalinterests of the Terai grassland ecosystemare to be secured.

There is increasing recognition in some partsof the world of the need to protect naturalhabitats against the impacts of canecultivation.

Protecting natural habitats insugar monoculture belts

Coastal heathland remnants of 500ha amid cane growingareas of New South Wales have been found to contain highdensities of 'natural-vegetation-dependent' bird species.

Botanical surveys in Sao Paulo, Brazil, showed that botanicaldiversity was similar in a 20ha protected fragment of cerradohabitat in an agricultural area including sugar cane, comparedto that measured in other cerrado areas.

In South Africa, regulations apply to the cultivation of virginland, and to the cultivation of cane in close proximity to certainnatural habitats. For example, a permit is required before anyvirgin or new land can be planted with cane – in this context,any area that has not been cultivated for ten years or more isregarded as virgin land. Natural wetlands are also protectedfrom drainage and cultivation by a Conservation Act and caneshould not be planted within 10m of indigenous forest, wetlandor riparian habitats, or in flood plains.

Typical cerrado habitat with medium

sized tortuous trees, Pirenopolis area,

Cerrado, Brazil.

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A rehabilitated waterway on a

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A correctly buffered

wetland in South Africa.

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Soil conditioners and fertilisersFilter press mud from cane mills is oftenincorporated into soils as a conditioner andfertiliser.

A number of studies suggest that vinasseand treated waste water from sugar canemills is suitable for irrigation, although thereis concern that these products have thepotential to pollute soils and groundwaterand cause salinisation, especially if used inlarge amounts; irrigation with cane effluentwas found to suppress germination of peasin Balrampur, India.

Bagasse has been used as a mulch to aidre-vegetation and stabilisation of denudedland on road verges and can also be usedas an excellent substrate for mushroom

cultivation, with the cultivation residuepotentially used in animal feed. Sugar beettops can be left on the soil surface of fields,as a source of nitrogen for the next crop inthe rotation.

Paper productionBagasse is used in a number of countriesin production of paper and particle board.

Animal feedThe value of sugar beet by-products asanimal feed was recognised very early in thecultivation of the plant. Fresh beet tops canbe grazed in the field (common practicewhen they are fed to sheep) or removedfrom the field to be fed directly to livestockor to be used for silage. Vinasse productionfrom beet molasses can also be used inanimal feed, as can beet pulp residues, eitherdirectly or mixed with molasses and dried.

Use of by-productsand alcohol production

Sugar is not the only product of cane or beetand in fact only represents 17 percent of thebiomass of the sugarcane plant. In addition tothe use of cane bagasse for boiler fuel, there aremany other sugar processing by-products thatcan be used for a range of purposes.This increases the efficiency of the crop and,where by-products are used as soil improvers,provides organic alternatives to chemical inputs.

Bagasse stacked ready to be used

for chip-board production.

In combination with Effective Microorganisms (EM), sugarcane filter cake was superior to farmyard manure and poultrymanure in sustaining crop yield and soil properties in irrigatedwheat fields in Faisalabad, Pakistan.

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FiltrationFly ash extracted from boiler chimney gascan be used as a filtration aid in the sugarmill and can also be used for the removal ofcertain pesticides from wastewater.

Chemical productionBagasse is a potentially valuable cellulosesource for the production of chemicals, suchas pentosans (including furfural) and alliedsubstances.

Yeast productionMolasses produced in the processing ofcane or beet sugar is an important rawmaterial for the fermentation industry and inthe production of yeasts.

Alcohol productionIn some parts of the world alcohol hastraditionally been produced as a by-productof the sugar industry, through thefermentation of molasses and subsequentdistilling, typically to produce rum. However,river pollution near distilleries poses aproblem, particularly in Brazil where theNational Alcohol Programme was launchedin 1975.

Fuel productionJuice extracted from cane can also befermented directly and the products distilledto produce alcohol for fuel (bioethanol).The primary argument in favour of bioethanolas a fuel is that it results in less air pollutionthan fossil fuels. Other potential advantagesinclude the renewable nature of bioethanol,reduced dependence on foreign oil,enhanced local employment opportunitiesand the creation of ‘added value’ in a sugarindustry.

Electricity productionSugar cane has the advantage in mostcountries where it is processed of producingsurplus steam and electricity from bagassewhich is effectively ‘free’ and increases thesustainability of sugar production.

Press mud biofertiliser: a phosphorous rich by-

product from sugarcane mills that can help

overcome phosphorus deficiencies which are

common in countries such as Pakistan & India.

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Up to 97-98 percent removal of lindane and malathionpesticides was obtained using fly ash under optimumconditions in India, providing an inexpensive and effectiveoption for filtering waste water.

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Encouraging the use ofBetter Management Practices

With regard to water resources thiswould mean:

• Higher farm productivity(more crop per drop)

• Benefits for local communities (moredrop per person) and the environment(more drop per ecosystem)

• Wider socio-economic development, aswater will be available for other usessuch as fisheries or ecotourism (moredollars per drop).

In sugar production the uptake of suchpractices is beginning, but there are stillconstraining factors which include:

• Few incentives for the implementationof BMPs, such as realistic charges forwater used and reliability of irrigationwater delivery;

• Information not reaching farmers aboutBMPs;

• Poor access to (micro) finance neededby farmers to invest in BMPimplementation;

• A lack of regional, national andinternational policies that encouragesustainable sugar production;

• Consumer demand for ever cheaperfood products.

Action is consequently needed at local,national and international levels:

Extension servicesGovernment, mill and other extensionservices that support farmers can integrateBMPs more strongly into their trainingprogrammes. In particular, mills canencourage practices that benefit themselvesand the farmer, such as the use of mill by-products for soil improvement.

NGOsLocal and international NGOs can encouragedialogue between extension, researchcentres, innovative farmers, sugar mills andbanks for the development and expansionof field trials. Local NGOs can also supportthe establishment of cooperative farmingmethods and Farmer Organisations toincrease economic returns to farmers andhelp spread BMP knowledge.

National governmentsPolicies measures which support the uptakeof BMPs can be introduced by national andlocal governments, such as:

• Sucrose-based payments for farmers,instead of cane-weight.

• Improved irrigation water allocation,defined water rights for farmers, and thepossibility to sell or barter any excesswater.

• Charges for polluting water bodies.• Protection of high biodiversity areas to

prevent expansion of cultivation.

National sugar associationsIndustry associations can develop BMPsupport programmes, such as the BMPguidelines produced by the South AfricanSugar Association (SASA), or those of theAustralian Canegrowers Council.

Corporate sectorResponsible companies can provide supportthrough their purchasing decisions bydeveloping a global approach for sugarsourcing that encourages BMP adoption.

International sugar marketsEighty percent of world sugar productionand sixty percent of international trade isproduced at subsidised or protected prices.The EU, USA, and Japan have averageproducer prices that are more than doublethe world market price due to subsidies; thiscontributes to low and volatile world sugarprices. Policy reform is needed to enabledeveloping countries to reduce poverty byexporting more sugar, while supporting themto implement BMPs appropriate to their localcircumstances that will increase long-termsustainability of sugar production.

Further InformationCheesman, O.D. (2004). EnvironmentalImpacts of Sugar Production: the Cultivationand Processing of Sugarcane and SugarBeet. CAB International, Wallingford, UK.(www.cabi-publishing.org)

Clay, J. (2004). World Agriculture and theEnvironment: a Commodity-by-CommodityGuide to Impacts and Practices. Island Press.(www.islandpress.org)

IFC/WWF. (2004). Better ManagementPractices and Agribusiness Commodities,Phase Two: Commodity Guides (ResearchReport for IFC Corporate Citizenship Facilityand WWF-US).

Rabobank. (1999). The World of Sugar andSweeteners. Rabobank International.Utrecht. The Netherlands.

Sugar produced using BetterManagement Practices (BMPs) canimprove financial returns to farmersand millers – through increasedyields, sustained soil health,reduced inputs and enhanced

quality of production – as well as providing benefitsfor businesses that use sugar in their products.

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Machine harvesting of sugar cane.

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