general enquiries on this form should be made...

General enquiries on this form should be made to:Defra, Science Directorate, Management Support and Finance Team,Telephone No. 020 7238 1612E-mail: [email protected]

SID 5 Research Project Final Report

SID 5 (Rev. 3/06) of 23

NoteIn line with the Freedom of Information Act 2000, Defra aims to place the results of its completed research projects in the public domain wherever possible. The SID 5 (Research Project Final Report) is designed to capture the information on the results and outputs of Defra-funded research in a format that is easily publishable through the Defra website. A SID 5 must be completed for all projects.

This form is in Word format and the boxes may be expanded or reduced, as appropriate.

ACCESS TO INFORMATIONThe information collected on this form will be stored electronically and may be sent to any part of Defra, or to individual researchers or organisations outside Defra for the purposes of reviewing the project. Defra may also disclose the information to any outside organisation acting as an agent authorised by Defra to process final research reports on its behalf. Defra intends to publish this form on its website, unless there are strong reasons not to, which fully comply with exemptions under the Environmental Information Regulations or the Freedom of Information Act 2000.Defra may be required to release information, including personal data and commercial information, on request under the Environmental Information Regulations or the Freedom of Information Act 2000. However, Defra will not permit any unwarranted breach of confidentiality or act in contravention of its obligations under the Data Protection Act 1998. Defra or its appointed agents may use the name, address or other details on your form to contact you in connection with occasional customer research aimed at improving the processes through which Defra works with its contractors.

Project identification

1. Defra Project code WU0114

2. Project title

The Use of Environmental Footprints in Horticulture: Case Studies

3. Contractororganisation(s)

Warwick HRIUniversity of WarwickWellesbourneWarwickCV35 9EF

54. Total Defra project costs £ 59,331(agreed fixed price)

5. Project: start date................ 01 April 2008

end date................. 31 July 2009

SID 5 (Rev. 3/06) of 23

6. It is Defra’s intention to publish this form. Please confirm your agreement to do so...................................................................................YES NO (a) When preparing SID 5s contractors should bear in mind that Defra intends that they be made public. They

should be written in a clear and concise manner and represent a full account of the research project which someone not closely associated with the project can follow.Defra recognises that in a small minority of cases there may be information, such as intellectual property or commercially confidential data, used in or generated by the research project, which should not be disclosed. In these cases, such information should be detailed in a separate annex (not to be published) so that the SID 5 can be placed in the public domain. Where it is impossible to complete the Final Report without including references to any sensitive or confidential data, the information should be included and section (b) completed. NB: only in exceptional circumstances will Defra expect contractors to give a "No" answer.In all cases, reasons for withholding information must be fully in line with exemptions under the Environmental Information Regulations or the Freedom of Information Act 2000.

(b) If you have answered NO, please explain why the Final report should not be released into public domain

Executive Summary7. The executive summary must not exceed 2 sides in total of A4 and should be understandable to the

intelligent non-scientist. It should cover the main objectives, methods and findings of the research, together with any other significant events and options for new work.

The environmental impact of agriculture is under scrutiny since the production of food, fibre and fuel covers 80% of the UK’s land surface and agriculture is responsible for 7.5% of the UK’s greenhouse gas (GHG) emissions. Specifically, agriculture in the UK is responsible for 74% of nitrous oxide (N2O) and 38% of methane (CH4) emissions (Defra, 2007a) and food production has a direct impact on air, water and soil quality. Many factors influence the environmental impact of agriculture; inputs of energy, fertilizers and pesticides have direct effects but regional differences in soil type and rainfall also contribute. Different crops require different levels of The aim of this study was to collect data and calculate the environmental footprint of selected crops grown in the UK. The environmental footprint is based on four existing indicators (carbon footprint, pesticide assessment, eutrophication and acidification, water use), which are combined to present an overall assessment of environmental impact. A previous project, WQ0101 (Defra, 2007b) used standard data to estimate the environmental footprint of twelve agricultural and horticultural crops and showed that there was considerable variation between the different crops in respect of their environmental impact. The present study uses ‘real’ data from two geographically separate areas. The environmental footprint presented in this study is an area based assessment and does not take account of crop yield although the methodology could be developed to account for crop yield in the future.

Data were collected from nineteen farms, totalling 5,918 hectares, in Sussex and Lincolnshire, and used to calculate environmental footprints for 106 crops and livestock types. The boundary for the study was the farm gate; the energy required to store, dry and cool the commodity was included but all packaging and transport were excluded.

The data confirmed that crops have a wide range of environmental footprints with the smallest being for organic fodder rape (3) and the largest for conventional celery (289). The average value for an environmental footprint was 25 and nine crops had larger footprints and 38 crops smaller footprints. This skewed distribution reveals that a small number of crops (potato, onion,lettuce and celery in this study) can have a profound environmental impact. Environmentalfootprints for the major crops were as follows: pea (15), sugar beet (15), all cereals (19), oil seed rape (19), winter wheat (21), brassicas (22) and potato (39).

The environmental impact of horticultural crops was highly variable: celery (289), lettuce (204) and onion (50) recorded some of the highest environmental footprints but occupied only a small

SID 5 (Rev. 3/06) of 23

area, whilst the environmental footprint of the more mainstream horticultural crops (brassicas e.g. Brussels sprout, cabbage, calabrese, cauliflower) were similar to the main arable crops (winter wheat, winter barley, oil seed rape). Of the main field crops, potato had the largest environmental footprint. Data were collected on a small number of livestock systems but were too variable to reach any meaningful conclusions.

The four separate indicators (carbon footprint, pesticide assessment, eutrophication and acidification, water use) within the environmental footprint were given the same degree of influence, which was a pragmatic decision based on the concepts of fairness and consistency. The influence of the individual indicators varied with crop, farming system and region. Potato crops had larger carbon footprints compared with most crops but a large amount of the variability within potato environmental footprints is in the use, or not, of water for irrigation. Potato crops also receive high levels of pesticides, although the difference between the conventional and organic systems was smaller than expected, due to the use of copper to control blight in organic systems. Regional differences were apparent in winter wheat where production in Sussex resulted in environmental footprints that were 30% greater compared with Lincolnshire. This was because the carbon footprint, pesticide applications, eutrophication and acidification potential were all greater in Sussex, while water use was similar in both regions.

The environmental footprint is a new way of assessing existing indicators and the aim is to provide greater insight than through examination of the four indicators individually. Assessment of the influence of an individual indicator within the environmental footprint can highlight particular issues. Recent work has concentrated on carbon footprints but the present study has shown that, for some crops, pesticide and water use may be of greater concern. This concept has been recognised by Defra in the recent Food Matters report (Defra, 2009), which considers the introduction of environmental labels on food. The environmental footprint could form the basis of a future methodology to meet this goal.

Although, it will be obvious to agronomists, this study has confirmed that there can be large regional differences in the inputs applied to crops, and consequently, in subsequent outputs and emissions. For example, there was a considerable difference in the size of the environmental footprint of winter wheat between Sussex and Lincolnshire. Although such differences can be explained partially by regional differences in soil and weather, we suggest that the environmental footprint of many crops could be reduced by the greater dissemination of agronomic information. Within a region, benchmarking of the major environmental indicators would be a good starting position. Benchmarking could consider the environmental footprint in terms of both area and yield and allow estimation of an ‘optimum’ environmental footprint for any particular crop, with the aim of achieving maximum yield with minimum environmental impact.

Project Report to Defra8. As a guide this report should be no longer than 20 sides of A4. This report is to provide Defra with

details of the outputs of the research project for internal purposes; to meet the terms of the contract; and to allow Defra to publish details of the outputs to meet Environmental Information Regulation or Freedom of Information obligations. This short report to Defra does not preclude contractors from also seeking to publish a full, formal scientific report/paper in an appropriate scientific or other journal/publication. Indeed, Defra actively encourages such publications as part of the contract terms. The report to Defra should include: the scientific objectives as set out in the contract; the extent to which the objectives set out in the contract have been met; details of methods used and the results obtained, including statistical analysis (if appropriate); a discussion of the results and their reliability; the main implications of the findings; possible future work; and any action resulting from the research (e.g. IP, Knowledge Transfer).

SID 5 (Rev. 3/06) of 23

1. Background

The environmental impact of agriculture is under scrutiny since the production of food, fibre and fuel covers 80% of the UK’s land surface and agriculture is responsible for 7.5% of the UK’s greenhouse gas (GHG) emissions. More importantly, agriculture is responsible for 74% of nitrous oxide (N2O) and 38% of methane (CH4) emissions (Defra, 2007a). Agriculture and food production have a direct impact on air, water and soil quality and farming shapes the landscape that we live in. However, food is essential so the environmental impacts of production have to be considered in that context.

Many factors influence the environmental impact of agriculture. Inputs like energy, fertilizers and pesticides have obvious direct impacts but regional differences, soil type and rainfall also contribute to environmental impact. Different crops require different levels of inputs, for example, potatoes require more fertilizer, pesticides and water compared to winter wheat. There are only a small number of arable crops but horticulture covers a wide and diverse range: bulbs and outdoor flowers, field vegetables, hardy nursery stock, mushrooms, protected crops, soft fruits, tree fruits and cross sector. The area occupied by horticulture, excluding potatoes, is one-twentieth of the land occupied by cereals, and covers under 1% of the total UK agricultural area. There is an assumption that horticulture has minimal impact on the environment, and hence that there is little to be gained from reducing impacts on the environment compared to other sectors of agriculture. However, the diversity of horticulture means that some crops can have an environmental impact which is completely out of proportion to the area grown.

A previous project, WQ0101 (Defra, 2007b) used environmental footprinting to assess the generic environmental impact of twelve different horticultural and agricultural crops and showed that although the environmental impact of the horticultural sector at the UK scale was minimal, some horticultural production had environmental impacts at field scale that were greater than arable crops. The report revealed two sectors where further investigation could be useful: (1) fertilizer, pesticide and water use in the protected sector (glasshouses and polytunnels) and (2) fertilizer use in irrigated field vegetables. In addition, there was a lack of data relating to greenhouse gas emissions from the production of all horticultural crops.

2. Objectives

The aim of this study was to assess the environmental impact of agricultural production (arable, mixed, horticultural) crops within two specific geographical areas. This was achieved by the collecting whole farm data from Sussex and Lincolnshire which was then used to construct environmental footprints. The footprints were then used to map the results and identify ‘hot spots’ of environmental impact. The objectives were:

1. Identify two contrasting areas of horticultural production.2. Collect data relating to all agricultural and horticultural production within those two areas.3. For both areas, calculate the environmental footprint of all the agricultural and horticultural

enterprises and determine the overall environmental burden of horticulture as a proportion to the total burden.

4. For both areas, determine the relative environmental burden of horticulture by HDC sectors.5. Identify specific environmental issues and in conjunction with the area CSF officers and the

HDC propose strategies for mitigation.6. Map the environmental impacts within both area7. Recommend improvements, identify knowledge gaps and make suggestions for future research.

3. Materials and methods

3.1. Agricultural holdings

The study identified two areas of mixed horticultural and agricultural production: Chichester in West Sussex and Kirton in Lincolnshire. The area surrounding Chichester is known for glasshouse vegetables and early salad production but also supports production of potatoes, cereals and mixed horticulture; Kirton is known for field horticulture but also supports a full range of arable crops.

SID 5 (Rev. 3/06) of 23

Chichester has a warm and sunny climate and clay-loam soils while Kirton has a mild climate on silt soils.

Chichester: salads, cereals, OSR, potatoes; Kirton: mixed field vegetable production (Brassica’s, bulbs and root crops), cereals, potatoes, peas,

sugar beet.

Although the two areas are different, they share a number of crops (notably winter wheat and potatoes) that enable comparisons to be made. The study identified twenty-seven farmers and growers who were approached to provide data which resulted in nineteen separate holdings being assessed. Farmers and growers were visited twice. The first time was an introductory meeting to outline the project and to seek their assistance while the second visit, six to eight months later, was to collect data. Data for all crops, grown in the 2007/8 cropping year, were collected. This included the following inputs used in production: growing media, seed, seedlings, individual fertilizer and pesticide applications, direct and indirect energy (diesel, petrol, electricity, gas) and water.

3.2. The environmental footprint

The environmental footprint is a collection of four existing indicators (carbon footprint, pesticide score, eutrophication and acidification (EAP) score, water use) combined to present an overall assessment of environmental impact. The boundary for the environmental footprint is the farm gate which includes the energy required to store, dry and cool the commodity but excludes all packaging, both transport and point of sale. A fuller description and methodology for the environmental footprint can be found in Defra (2007b) and Lillywhite (2008).

3.3. Carbon footprint (CO2e)

Although the full Intergovernmental Panel on Climate Change (IPCC, 2006) basket of greenhouse gases includes hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulphur hexafluoride (SF6), nitrogen trifluoride (NF3), trifluoromethyl sulphur pentafluoride (SF5CF3), halogenated ethers and some other halocarbons not covered by the Montreal Protocol, this analysis concentrates on the main three gases emitted from agriculture: carbon dioxide, methane and nitrous oxide.

Table 1. Greenhouse gases and their warming potential

Burden Global warming potentialCO2 (carbon dioxide)CH4 (methane)N2O (nitrous oxide)

125

298

Global warming potential (GWP) is used to assess the abilities of different greenhouse gases to trap heat in the atmosphere and is based on the radiative efficiency (heat-absorbing ability) of each gas relative to that of carbon dioxide (CO2), as well as the decay rate of each gas (the amount removed from the atmosphere over a given number of years) relative to that of CO2. The GWP provides a basis for converting emissions of various gases into a common measure, which allows the radiative impacts of various greenhouse gases to be aggregated into a single measure, the carbon footprint, measured in terms of carbon dioxide equivalent (CO2e) over a 100 year span (Table 1). The methodology used for calculating the carbon footprint follows that of PAS2050 (BSi) with the following refinements / information:

Carbon dioxide – includes direct emissions from the combustion of fossil fuels (diesel and LPG) and electricity. Indirect emissions (embedded) are calculated for fertilizers (Jenssen & Kongshaug, 2003) and pesticides (Barber, 2004);

Methane – direct emissions from livestock are estimated using the IPCC Tier 1 method; Nitrous oxide – direct emissions from fertilizers and crop residues are included as are indirect

emissions from nitrate; these are estimated using the IPCC Tier 1 method.

SID 5 (Rev. 3/06) of 23

3.4. Pesticides

The Environmental Impact Quotient (EIQ) method (Kovach et al., 1992) is used to quantify the environmental impact of all pesticide applications. This method reduces the environmental impact information for an active ingredient to a single value by combining the three principal components of agricultural production systems: a farm worker component (applicator and picker), a consumer component (health and leaching) and an ecological component (fish, birds, bees and beneficials). Each component is given equal weight in the final analysis, but within each component, individual factors are weighted differently. Coefficients are used to give additional weight to individual factors on a one to five scale. Factors carrying the most weight are multiplied by five (applicator and beneficials), medium-impact factors (bees and birds) are multiplied by three, and those factors considered to have the least impact are multiplied by one. A consistent rule throughout is that the impact potential of a specific pesticide on an individual environmental factor is equal to the toxicity of the chemical multiplied by the potential for exposure. Stated simply, environmental impact is equal to toxicity multiplied by exposure. For example, fish toxicity is calculated by determining the inherent toxicity of the compound to fish multiplied by the likelihood of the fish encountering the pesticide. In this manner, compounds that are toxic to fish but short-lived have lower impact values than compounds that are toxic and long-lived. A field rating for each pesticide is achieved by multiplying the EIQ value by the weight of the active ingredient that is applied.

EIQ value * rate of active ingredient * application rate = EIQ Field Use Rating

Example for Makhteshim’s Alpha Linuron in potatoEIQ 40.3 * 0.5 * 4.2 l ha-1 = 84.63 ha-1

Data on pesticide use was extracted from the farmers/growers own records. Every single application was assessed using the EIQ method. This is a laborious business, given the vast range and type of pesticides used in the UK, but it was hoped that this approach would give a more accurate picture of pesticide use compared to the more commonly adopted method of using the total weight of active ingredients (Williams et al., 2006).

3.5. Eutrophication and acidification potential

Eutrophication Potential (EP) is defined as the potential of nutrients to cause over-fertilization of water and soil which in turn can result in increased growth of biomass. It is quantified in terms of phosphate equivalents using the factors in Table 2.

Table 2. The eutrophication potential of selected nutrients

Burden Eutrophication potential (as PO4)PO4 (phosphate)NO3 (nitrate)NH3 (ammonia)NOx (oxides of nitrogen)

1.000.420.330.13

Acidification is a consequence of acids (and other compounds which can be transformed into acids) being emitted to the atmosphere and subsequently deposited in surface soils and water. Increased acidity of these environments can result in negative consequences for coniferous trees (forest dieback) and the death of fish in addition to increased corrosion of manmade structures (buildings, vehicles etc.). Acidification Potential (AP) is based on the contributions of SO2, NOx and NH3 and is quantified in terms of sulphate equivalents using the factors in Table 3.

Table 3. The acidification potential of selected nutrients

SID 5 (Rev. 3/06) of 23

Burden Acidification potential (as SO2)

SO2 (sulphur dioxide)NOx (oxides of nitrogen)NH3 (ammonia)

1.000.701.88

The eutrophication and acidification factors are based on the work of Azapagic (2003 & 2004) and are combined in this report. The results are reported as kg ha-1.

3.6. Water

The majority of water use in agricultural and horticultural crops is during the summer when there may potentially be a shortage in supply. If, as a result of climate change, summers are to be longer and drier, then water shortages and /or the increasing cost of water may have an environmental impact. Water footprinting methodology generally recognises two types of water: green water is soil water replenished by rainfall while blue water is contained within rivers and ground sources and is the water supplied by the water companies (Hoekstra & Chapagain, 2008). This study reports total (blue) water use in litres per hectare per year.

3.7. Calculation of the overall environmental footprint

The indicators that form the environmental footprint use the same base unit, the hectare, however, the values that the individual indicators can adopt varies greatly. The minimum is always zero but the maximum value can be flexible. A previous study (Defra, 2007b) used an arbitrary value but this study, having access to ‘real’ data, calculated a maximum value. The maximum value was calculated by scaling the individual scores for each indicator to a value between 0 and 100 and then making the average indicator score 25. The environmental footprint is the average of the four indicators which consequently means that the average score for each individual indicator is 25 as is the average environmental footprint.

All four indicators have equal weight within the environmental footprint which was done in interests of consistency and because it allows their individual influence within the finished footprint to be easily assessed; however, this is an area where the methodology could be developed and refined to reflect different farming and environmental policy in the future. Indicators could also be added (or deducted) to allow analysis of specific policy questions or goals. In all cases the higher the value of the individual indicator then the greater the environmental impact. Table 4 lists the indicators with their respective minimum and maximum values. In conclusion, the environmental footprint is the non-weighted mean (other than the weighting related to the maximum value) of four indicators and is expressed on a hectare basis but has no other units.

Table 4. Environmental footprint indicators

Indicator Unit Minimum value

Maximum value

Average value

Scaled footprint

valueCarbon footprintPesticide EIQ ratingEAPWater

kg ha-1

kg ha-1

kg ha-1

litres ha-1

0000

11,612434

92142,301

2,905108

2335,905

25252525

4. Results and discussion

In total, nineteen separate farmer/growers holdings were assessed totalling 5,918 hectares; the holdings comprised different farm types: arable, mixed, livestock and field vegetables. No conscious decision was made to target conventional or organic farms although organic production systems are perhaps over-represented in the study. Table 5 lists the region, number of holdings, the production system and area within the study.

SID 5 (Rev. 3/06) of 23

Table 5. Holdings, area and crop type/system (by region)

Area Number of holdings System (crops) Area (ha)

Kirton 10 Conventional (14)Organic (18)

2,0151,115

Chichester 9 Conventional (27)Organic (1)

2,464324

In total, 38 different crops were assessed on both conventional and organic systems resulting in 48 crop/system combinations.

4.1. The relative environmental burden of agriculture by sector/system

The results are reported and considered by crop and system; this approach allows comparisons to be made between crops (means where appropriate) and systems to identify those crops and sectors which have high environmental impacts. Since the four indicators have the same weight in the environmental footprint it is possible to use any variation to assess their individual influence within the footprint; In the text, the indicators are in the sequence [carbon footprint: EIQ pesticide score : EAP : water]; [25:25:25:25] would be an average score representing 2,905 kg/ha CO2e, 108 EIQ/ha, 23 kg/ha EAP and 35,506 litres water.

4.1.1. Cereals

Winter wheat is the best represented crop in the study which is unsurprising given that it occupies the largest area of agricultural land in the UK. Of the cereal crops in this study, winter wheat has the highest carbon footprint and pesticide score and consequently, the highest environmental footprint score. The ranking of winter cereals for carbon footprint: winter wheat > winter oats > winter barley, is the same as for their environmental footprint. Normally winter oats are seen as a low input crop that requires minimal nutrients so the fact that oats rank higher than barley is probably as result of limited data for winter barley. Of the conventionally grown crops, winter wheat received the highest amount of pesticides and winter oats, surprisingly, the second highest. Winter wheat also received the highest amounts of nitrogen and phosphate fertilizers which are reflected in the EAP score of 25. Table 6 contains the results.

Table 6. The environmental footprint of cereal crops

Crop System Sample size

CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue

(litre/ha)Environmental

footprint

Barley (spring)Barley (spring)Barley (winter)Oats (winter)Oats (winter)TriticaleWheat (spring)Wheat (winter)Wheat (winter)

OrganicConventionalConventionalOrganicConventionalOrganicOrganicOrganicConventional

11213121

15

1,2352,5192,196

9442,1991,0211,160

9052,957

019840

106000

135

1228178

198

146

25

0630

1,5750

1,2600

180

1,321

61414

416

442

21Cereals (mean)Cereals (mean)

ConventionalOrganic

216

2,7551,093

1200

2310

1,3035

195

All crops (mean) 106 2,905 108 23 35,905 25

A comparison between conventional and organic systems shows that conventional cereals have a bigger impact than organic cereals in all categories within the environmental footprint. The carbon

SID 5 (Rev. 3/06) of 23

footprint of organic cereals is 39% that of conventional cereals; the difference is the result of no pesticides being applied to organic cereals and minimal nitrogen nutrition although some FYM was applied. No irrigation was applied to any cereals in this study, so the higher water use in conventional systems is a result of spraying. Overall, the environmental impact of organic cereals was 26% of that of conventional cereals. The influence of individual indicators for conventional cereals was [24:28:25:1] and organic [9:0:10:0]. Since conventional cereals were the dominant crop within the data set used to scale the environmental footprint, this ‘average’ score is expected. Conventional cereals had lower than average carbon footprint and water use, an average EAP score and a higher than average pesticide impact.

Figure 1. The environmental footprint of cereal crops

0 5 10 15 20 25

Spring barley (o)

Spring barley (c)

Winter barley (c)

Winter oats (o)

Winter oats (c)

Triticale (o)

Spring wheat (o)

Winter wheat (o)

Winter wheat (c)

CO2 Pesticide EAP Water

4.1.2. Potatoes

Potatoes score highly in every indicator within the environmental footprint which is reflected in their overall scores which are amongst the highest in this study, with only some specialized horticultural crops being higher. Potatoes are a resource hungry crop, in terms of establishment, nutrition and protection. The high carbon footprint is the result of intensive field cultivation, especially at planting and harvest, fertilizer use (synthetic in conventional and FYM in organic) and manufacture of pesticides. Both conventional and organic potatoes receive high levels of fungicides to combat blight; this is reflected in the pesticide scores which are high in comparison to most other crops. The high amounts of nitrogen and phosphate applied to potatoes is reflected in the high EAP scores.

Table 7. Environmental footprint of potatoes


CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue


footprint

Potato (mean)Potato (mean)

ConventionalOrganic

83

4,4304,191

302270

3840

11,714304,502

3989

All crops (mean) 106 2,905 108 23 35,905 25

The carbon footprint of organic potatoes is 95% that of conventional potatoes and the pesticide scores are equally close, being 89% which is related to the use of copper for blight control in organic production. The use of FYM resulted in the EAP score for organic potatoes being higher than the conventional crop and greater amounts of water were used in organic potatoes to control common scab. In this study, the environmental footprint of organic potatoes was higher than conventional

SID 5 (Rev. 3/06) of 23

potatoes, but this is a consequence of uneven water use for irrigation within the sample farms and is unlikely to be replicated across the whole potato industry. If water is excluded from the comparison there is little difference between the two systems. The influence of individual indicators for conventional potatoes was [38:70:41:8] and organic [36:62:43:214] which, excluding water use, shows how similar conventional and organic systems are.

4.1.3. Other arable crops

Table 8. The environmental footprint of some other arable crops


CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue(litre/ha)

Environmental footprint

OSR (winter)Sugar beetPeaPeaBeans (winter)Beans (summer)

ConventionalConventionalConventionalOrganicOrganicOrganic

566211

2,6952,2671,6601,5841,2121,224

96926134

00

2617

911

76

6851,212

595308

00

191510854

All crops (mean) 106 2,905 108 23 35,905 25

The crops in this section are diverse but make up the balance of what are normally considered arable crops. Data on winter oil seed rape was only obtained from the Chichester area and data on sugar beet from Lincolnshire. Vining peas were grown in both areas although data comparison is made difficult because peas for other market avenues are grown in Chichester. Field beans are another common crop but only appeared in an organic system in Kirton.

Figure 2. The environmental footprint of some other arable crops

0 20 40 60 80

Spring bean (o)

Winter bean (o)

OSR (c)

Pea (c)

Pea (o)

Potato (c)

Potato (o)

Sugar beet (c)

CO2 Pesticide EAP Water

All the crops in this section have relatively low environmental footprints. They can all be considered break crops within an arable rotation and have lower carbon and environmental footprints compared to winter wheat. The difference between winter oil seed rape and sugar beet is down to fertilizer application; oil seed rape receives more than sugar beet. Peas and beans are legumes and do not normally receive any fertilizer which accounts for their lower carbon and environmental footprints. There is little difference between conventional and organic peas in this study as one of the organic crops received an approved organic insecticide and the conventional crops received no fertilizer. The

SID 5 (Rev. 3/06) of 23

beans in this study received no fertilizers or pesticides with a resultant low environmental footprint. The influence of individual indicators for conventional oil seed rape was [23:22:28:0], for conventional peas [14:14:10:0]; for organic peas [14:8:12:0] and conventional sugar beet [20:21:18:1];

4.1.4. Livestock and forage crops

Livestock and forage crops were not well represented in the study. Although two beef herds were assessed, their management systems were very difficult and it’s difficult to draw any meaningful conclusions; however, some observations can be made. Stocking rate is a greater influence in the carbon footprint than management system. The conventional system was an extensive system with a stocking rate of 0.6 cows per hectare while the organic system was intensive using a stocking rate of almost 4 cows per hectare. The conventional system used limited amounts of additional winter feed but the organic system relied heavily on home grown cereals to supplement the limited grazing. The carbon footprint in this study is based on area, not output unit, which favours the extensive system.

The single dairy system within the study was also organic. The cows were housed for six months over winter and fed on a mixture of home grown forage and domestic/imported concentrates. The herd were turned out in March and grazed at a stocking rate of 1.2 cows per hectare. The greatest influence within the carbon footprint was feed concentrates, especially imported organic soya.

Table 9. The environmental footprint of livestock and forage crops


CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue


footprint

BeefBeefDairySheep

ConventionalOrganicOrganicOrganic

1111

1,5588,8509,1911,837

4000

412

99

8,60145,84659,562

2,491

63033

7Fodder rapeLupins

OrganicConventional

11

5092,567

075

65

0126

311

All crops (mean) 106 2,905 108 23 35,905 25

4.1.5. Field vegetables

The study includes a wide and diverse selection of vegetable crops, 20 in total, but unfortunately little duplication across holdings or region. The range of crops is reflected in the wide range of component scores within the environmental footprint. For example:

carbon footprint: 1,248 – 6,743 CO2e kg/ha pesticide EIQ score: 0 – 635 eutrophication and acidification (EAP): 11 – 48 kg/ha water: 0 – 1,446,680 litres/ha environmental footprint: 6 - 289

Given this diverse nature, and range of scores, it isn’t possible to undertake any meaningful analysis of the whole vegetable sector, but better to concentrate on groupings. The Brassica crops include Brussels sprouts, cabbage, calabrese and cauliflower; grown both conventionally and organically. None of the crops in the study were irrigated which makes the comparison easier to undertake. Although the sample size is not large enough for detailed analysis, a clear trend is still apparent. Brussels sprouts and cabbage have the highest individual indicator scores and the highest environmental footprint. Calabrese and cauliflower are also very similar but have a lower environmental impact. The environmental footprint of conventional Brassicas is 22 [35:21:34:1] and organic 7 [13:0:13:0]. On average the Brassicas crops received higher than average rates of fertilizer which resulted in a high EAP score and lower than average pesticide applications.

SID 5 (Rev. 3/06) of 23

Table 10. The environmental footprint of Brassica crops


CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue


footprint

Brussels sproutsCabbageCalabreseCalabreseCauliflowerCauliflower

ConventionalConventionalOrganicConventionalOrganicConventional

352333

4,4204,3061,6383,4601,5083,647

14397

064

052

323315291129

1,5551,490

2421,201

1221,032

2724

819

619

Brassica (mean)Brassica (mean)

ConventionalOrganic

145

4,0081,560

900

3112

1,344170

227

All crops (mean) 106 2,905 108 23 35,905 25

Figure 3. The environmental footprint of Brassica

0 5 10 15 20 25 30 35

Brussels sprouts (c)

Cabbage (c)

Calabrese (c)

Calabrese (o)

Cauliflower (c)

Cauliflower (o)

CO2PesticideEAPWater

Table 11 contains details of the other vegetable crops. Three crops have higher than average environmental footprints: celery, lettuce and onions. Celery has a high carbon footprint as a result of using polythene to bring on early crop and the environmental footprint of both celery and lettuce is dominated by the use of water for irrigation; they are examples of high value, high input crops, they are both double cropped to some extent and receive fertilizer, pesticides and irrigation as required. These inputs are reflected in their high component scores and overall environmental footprint which is considerably higher than any other field crop. Sweetcorn is the only other vegetable crop in the study that is irrigated. Conventional onion has a below than average carbon footprint but its environmental footprint is high as a result of very high pesticide inputs.

SID 5 (Rev. 3/06) of 23

Table 11. The environmental footprint of other vegetable crops


CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue


footprint

AsparagusBroad bean

CarrotCelery

CourgetteDwarf bean

LettuceMarrow

OnionOnion

ParsnipPumpkinRed beetRhubarb

Runner beanSquash

Sweetcorn

ConventionalConventional

OrganicConventionalConventionalConventionalConventionalConventional

OrganicConventional

OrganicConventional

OrganicConventionalConventionalConventionalConventional

11111112121111111

2,4211,4601,2486,7432,9762,9703,7892,5022,7893,5001,3811,8402,9215,3612,2912,5302,423

200110

0184

6599

20240

0635

038

0216107

3144

2619173526272821331919254548202833

1,6141,849

9451,446,68

03,0411,641

1,006,249

1,775630

2,1481,293

6470

1,2951,2602,199

28,842

2415

8289

1820

204141550

8131837171522

All crops (mean) 106 2,905 108 23 35,905 25

Conventional non-irrigated vegetables have an average environmental footprint of 23 [31:30:31:0] which shows an above average use of inputs (except water) with a consequentially high EAP score. Organic vegetables have an average environmental footprint of 9 [15:0:21:0]; the relatively high (compared to other organic crops) EAP score is the result of using FYM to supply plant nutrients. The irrigated crops had an average environmental footprint of 172 [37:33:35:581]. Like potato, the results for vegetable crops are confusing due to irregular use of water for irrigation; where crops are irrigated it dominates the environmental footprint.

4.2. The relative environmental burden of agriculture by region

The UK has many regional differences (climate, soil type, market requirement) which contribute to the distribution of crops. Although the same crop appeared many times in both Sussex and Lincolnshire, in general their frequency was insufficient to provide a robust data set so for the purpose of comparison only winter wheat and potatoes are considered.

Table 12. Regional differences in the environmental footprint of winter wheat


CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue


footprint

ChichesterKirton


510

3,5602,655

174115

3022

1,0081,477

2619

The regional differences in cereal production are illustrated by examining the impact of conventional winter wheat. The environmental footprint of winter wheat grown in Chichester was 26 [31:40:32:1] which is 30% greater than the same crop grown in Kirton, where the environmental footprint was 19 [23:27:24:1]. The impact of growing winter wheat in Chichester was greater for three indicators (carbon footprint, pesticide score, eutrophication and acidification potential) and the same for one (water use). The carbon footprint was heavily influenced by the manufacture and use of nitrogen fertilizer. The average application rates in Chichester and Kirton were 225 and 174 kg/ha, respectively and the 50 kg/ha difference explains why the carbon footprints are different and also contributes to difference in the EAP scores. Pesticide use was also higher in Chichester, 7.1 kg/ha active ingredient compared to

SID 5 (Rev. 3/06) of 23

4.8 kg/ha at Kirton. We attribute these differences to cultural practices associated with pest and disease control and better quality soil in Kirton requiring less fertilizer.

Table 13. Regional differences in the environmental footprint of potato


CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue


footprint

ChichesterKirton


53

4,3464,569

208459

3740

2,48927,089

3252

The production of potatoes demonstrates some regional and management differences. The environmental footprint of potatoes grown in Kirton was 52 [39:106:44:19] which is 60% higher than the same crop grown in Chichester, where the environmental footprint was 32 [37:48:40:2]. The carbon footprint and EAP for the two regions are very similar illustrating that field cultivations and fertilizer use did not vary that greatly; on average growers applied 183 and 203 kg/ha nitrogen in Kirton and Chichester, respectively. One big difference is in the use of pesticides where growers in Kirton used greater amounts of, higher impact, ingredients compared to Chichester growers, 14.0 and 18.9 kg active ingredient/ha, respectively. The use of irrigation is also very uneven and contrary to expectations the majority of growers contacted did not irrigate potatoes. This is because a high proportion of the potatoes were grown on rented land without access to a water supply. None of the growers in Chichester irrigated potatoes. The difference in the environmental footprints is due to pesticide and water use.

Regional differences were detectable in Brassicas. Although the environmental footprints for Chichester and Kirton were almost the same, 22 [38:13:35:1] and 23 [33:23:33:1] respectively, there were differences in the individual indicators. The carbon footprint was higher in Chichester but pesticide use was higher in Kirton.

This example demonstrates that different inputs can be substituted but the environmental footprint can remain unaffected. The potato and Brassica data set are too small to allow any firm conclusions regarding regional differences but do suggest that they can affect the environmental footprint of the same crop. The use of pesticides (fungicides) and irrigation is, obviously, dependent on factors other than region (climate related differences may have a bigger influence) although the difference in use between regions is interesting and could potentially contribute to better understanding of the pressures to use pesticides, especially fungicides.

The data set for conventional winter wheat is more robust and can be used to draw some conclusions. There are obvious differences between the regions with farmers in Chichester scoring higher overall and in three out of the four indicators. The differences may appear fairly small but extrapolated to the UK as a whole they become significant. In 2008, the UK grew 2,080,000 hectares of winter wheat. If the difference between the region’s carbon footprints (905 kg CO2e ha) is used as an example and if it was possible to grow all wheat at the lower carbon footprint, the saving would be nearly 2 million tonnes CO2e.

4.3. The environmental burden of horticulture compared to other sectors.

Horticulture is often assumed to be a high input and intensive farming system and in many respects, especially labour inputs, that is true. It is certainly true that some vegetable crops have very large environmental footprints and that variation across crops can be considerable (in this study, the range for conventionally grown crops was between 13 for pumpkin to 289 for celery) but overall the environmental footprint of vegetable crops was 23 compared to 19 for winter wheat; to put this into context, the environmental footprint of potatoes is considerably larger at 39 and double that of cereals and most vegetables (Table 14).

Although there are examples of vegetable crops with high environmental footprints: celery, lettuce and onion, the area that they occupy is small in comparison to cereals and other arable crops and the

SID 5 (Rev. 3/06) of 23

higher environmental impacts involved in their production may only be significant at a local level. Regionally or nationally, the arable and livestock sectors remain the dominant factor for overall environmental impact.

Table 14. The environmental footprint of selected conventional field crops


CO2e (kg/ha)

Pesticide(EIQ/ha)

EAP(kg/ha)

Water, blue


footprint

CerealsOSR (winter)PotatoSugar beetPeaVegetables

ConventionalConventionalConventionalConventionalConventionalConventional

215866

29

2,7552,6954,4302,2671,6603,460

12096

3029261

134

23263817

928

1,303685

11,7141,212

5951,546

191939151023

All crops (mean) 106 2,905 108 23 35,905 25

4.3.1. Ranking of results

The range of environmental footprints in this study was wide; the smallest was organic fodder rape at 3 and the largest was celery at 289. The environmental footprint of conventional celery was 96 times greater than organic fodder rape (Figure 4).

Figure 4. The environmental footprint of selected crops

SID 5 (Rev. 3/06) of 23

The average environmental footprint (25) is located between crops 38 (asparagus) and 39 (Brussels sprouts) showing that the data set is skewed towards a limited number of crops with high environmental footprints (and high irrigation requirement).

Organic crops tend to have lower environmental footprints compared to conventional crops; the nine smallest environmental footprints belong to organic crops and six organic crops are inter-dispersed within the conventional crops. However, growing crops organically is no guarantee of a low environmental footprint since three organic crops have higher than average (25) environmental footprints: beef (30), dairy (33) and potato (89). Some crops, for example, peas, which normally receive no fertilizer and minimal pesticides, show little difference in their environmental impact. On occasions, for example potato, organic crops may have a higher environmental footprint compared to their conventional equivalent since the use of alternative plant nutrients (FYM not fertilizer), plant protection (copper based not synthetic) and disease control (water for scab) may have a higher environmental impacts.

SID 5 (Rev. 3/06) of 23

4.4. Lowering the environmental footprint

4.4.1. Winter wheat

The environmental footprint of conventional winter wheat ranged between 15 and 29. Although regional and cultural differences account for some of the differences, the data and analysis shows that there is scope to lower individual environmental footprints through adopting different management strategies. Depending on soil type, applications of nitrogen fertilizer ranged from 116 to 257 kg/ha (average 191 kg/ha) so reductions are possible in overall amounts without affecting yield, however changing the type of nitrogen fertilizer can also be effective since some types have lower embedded energy (and hence carbon footprints) compared to others. Only two, out of fifteen, farmers applied phosphate fertilizers so the eutrophication potential is almost entirely based on nitrogen fertilizer. If soils start to become deficient in phosphorus and applications of phosphate fertilizers increases, it is likely that eutrophication will increase

The amounts of applied pesticides also varied greatly with the weight of active ingredient ranging between 2.8 and 8.2 kg/ha (average 5.5 kg/ha) with a corresponding EIQ pesticide score between 59 and 210. Given this range, we suggest that there must be further opportunities to lower pesticide use without adversely affected yield and quality; reductions are likely to be triggered by changes to cultural approach.

4.4.2. Potato

Potatoes are an interesting crop since the growing system, conventional or organic, is not necessarily the major factor in controlling the size of the environmental footprint. Potatoes normally require additional plant nutrients and that input can be mineral fertilizers, farm yard manure or fertility building in organic systems; all three increase the carbon footprint. In this study, the lowest and highest carbon footprints both belonged to organic crops; fertility building over two years had the lowest carbon footprint and farm yard manure the highest while the mineral fertilizers fell in between. Organic systems used on average 97 kg/ha nitrogen and conventional systems 191 kg/ha N; most growers also applied phosphate in one form or another. Greater emissions of nitrous oxide and ammonia from the use of farm yard manures in organic systems contributed to higher carbon footprints, eutrophication and acidification compared to some conventional systems. The eutrophication and acidification potential of organic and conventional systems also overlapped; the organic range was 15-45 kg/ha (average 34 kg/ha) and the conventional range was 37 to 52 kg/ha (average 43 kg/ha).

Application of pesticides also varied greatly with the weight of active ingredient used in conventional systems ranging between 11.2 and 32.1 kg/ha (average 16.1 kg/ha); organic growers also have access to pesticides and their use ranged between 0 and 5.4 kg/ha (average 3.5 kg/ha). The range of corresponding EIQ pesticide scores was between 55 and 185 for the conventional crops and between 0 and 83 for organic crops. The overlap between the two ranges is due to the fact that the copper based fungicides used by organic growers are more toxic than conventional fungicides.

The biggest influence in the environmental footprint of potatoes, irrespective of system, was the use of irrigation; non-irrigated crops had an average environmental footprint of 32 and irrigated crops of 109. If a crop is rain fed and has sufficient water for growth, the biggest improvement in the environmental footprint would be to cease using water to control potato scab.

4.5. Mapping the environmental impacts within both areas

Defra’s GIS data on river basin districts and catchment areas and the ArcGIS software was used to ‘map’ individual fields and holdings to provide an overview of the environmental impact of all cropping. The maps can identify individual, or clusters, of high environmental impact. Six maps are presented per area and show crop type, carbon footprint, pesticide rating, EAP, water use and environmental footprint, respectively.

Mapping at this level can help to understand the spatial distribution of environmental burdens associated with agriculture on a regional and country wide basis. Interpreting these maps is quite

SID 5 (Rev. 3/06) of 23

difficult. At a superficial level, they show the different types of cropping that occurs within a small area and can be used to quickly identify ‘hot-spots’ of individual or aggregated environmental burden.

At a more detailed level, it’s possible to draw some general conclusions. Mapping of CO2e across all crops and sectors isn’t that informative since the carbon footprint is an aggregation of multiple direct and embedded sources of three GHGs; it does identify hot-spots where inputs are high but field crops are rotated and growers of protected crops are aware that production has a high burden. It would be possible to map the individual gases but since GHGs are mobile and the problems that they cause are regional and global, the information that mapping provides doesn’t add greatly to our understanding or suggest possible solutions. However, carbon footprint mapping can be informative when restricted to a single crop since it illustrates very well the variation that occurs on a spatial basis.

The pesticide mapping is potentially more useful. Toxicity mapping could be use to site crops that require or receive high levels of potentially toxic active ingredients away from sites of population, soils types prone to leaching or water courses. The EAP mapping is similarly useful; crops receiving high levels of nitrogen and phosphate fertilizers could be sited away from water courses. Water mapping is perhaps not that useful at the small scale used in this study, however, if scaled up to catchment level could provide good information to the Environment Agency on demand for agricultural water.

Figure 5. Chichester. Crop type Figure 6. Chichester. Carbon footprint (CO2e/ha)

Figure 7. Chichester. Pesticide Figure 8. Chichester. EAP (kg/ha)

SID 5 (Rev. 3/06) of 23

Figure 9. Chichester. Water (blue, litre/ha) Figure 10. Chichester. Environmental footprint

Figure 11. Kirton. Crop type Figure 12. Kirton. Carbon footprint (CO2e/ha)

Figure 13. Kirton. Pesticide (EIQ/ha) Figure 14. Kirton EAP (kg/ha)

SID 5 (Rev. 3/06) of 23

Figure 15. Kirton. Water (blue, litre/ha) Figure 16. Kirton. Environmental footprint

Mapping of environmental footprints has the ability to quickly disseminate information on the environmental impact of multiple crops across large areas and to allow easy comparison between areas. A quick glance at the Kirton and Chichester maps reveals that agricultural production at Kirton has a lower environmental burden compared to Chichester. We suggest that soil type and quality influences this result almost to the same extent that choice of crop does.

The environmental footprint has a number of useful benefits. The individual indicators enable a more rounded assessment of environmental burdens, in comparison to just the carbon footprint, and the aggregated value allows easy comparisons to be made between different regions.

5. Conclusions

5.1. Environmental indicators

The carbon footprint is only one, out of four, indicators within the environmental footprint. Although carbon is currently at the fore front of environmental concerns, the use of pesticides and their impact on ecosystems, the eutrophication and acidification potential and water use are also important. Concerns over pesticide use and the effects of pesticide on human health and the environment rank only just behind carbon in public perception. Although eutrophication and acidification do not command the same public recognition as carbon and pesticides there is increasing concern that nitrate and phosphate and acidification are responsible for changing our ecosystems and reducing biodiversity. The UK is a water rich country yet the threat of climate change brings increasing concern that water hungry crops cannot compete with the public water supply and that certain crops may not be viable in certain parts of the country; additionally concerns over an increasing population and food security seem more tangible if you consider that we may have to increase domestic food production in the future. This will require more, not less, water.

The introduction of PAS2050 has resulted in the carbon footprint becoming an accepted environmental indicator. Quantification of methane and nitrous oxide, in addition to carbon dioxide, means that it is a useful indicator for agriculture. However, the impact of agriculture is far wider than just a carbon footprint and if the environmental impact of farming is to be really understood, other indicators are required to address the wider concerns. Indicators for pesticide use, eutrophication, acidification and water use are not new and have been used individually or as part of life cycle assessment studies before, however, aggregating them is new and allows new insights into existing farming practices and problems.

SID 5 (Rev. 3/06) of 23

5.2. Choice and influence of indicators

The environmental footprint concept was developed in the Defra project WU0101 (Defra, 2007) and was based on standard management data. It contained six indicators; the four used in this study plus ecological footprint and labour. The ecological footprint was dropped from this study and replaced by the carbon footprint since it covers much of the same ground; labour was dropped following feedback that it was a socio-economic, rather than an environmental indicator and eutrophication and acidification have been combined since they share a similar structure and impact.

Each of the four indicators was allocated the same influence with the environmental footprint. This was a pragmatic decision based on the concepts of fairness and consistency rather than any scientific principle. However, it is advisable to question whether the four indicators should be ranked the same. Is the carbon footprint of equal importance to the eutrophication and acidification potential? What criteria should be used to assess the indicator’s importance? Is it a simple environmental decision or are there wider social and economic issues to be considered? Can the influence of the individual indicators be varied depending on the policy question that is trying to be answered? The answer, of course, to most of these questions is that it depends on the user, but methods like the environmental footprint, which use aggregated indicators, have the advantage that they can be refined to answer policy type questions whatever the affiliation of the user.

An indicator is only valuable if it can be applied to all crops and its value constrained within a ‘normal’ range. We suggest that carbon footprinting, pesticide score and eutrophication and acidification meet these criteria. However, it is obvious that water use, especially for irrigation, does not. Water supply and security is becoming an increasingly important issue which suggests that water use must be considered within any environmental impact assessment, however, the on/off use of water within agriculture makes its inclusion within this environmental footprint a problem, since its dominance within certain crops can distort the value of the results. This problem could be resolved by omitting water use from the environmental footprint; this approach would make the results more consistent and would allow better comparisons to be made but another approach would be needed to assess the environmental impact of water use. Alternatively, the influence of water use within the environmental footprint could be changed, for example, by reducing it to 10% compared to the current 25% of the total. However, this approach then questions the importance, or rank, of all the individual indicators within the footprint. Currently they have equal rank. The alternative, unequal ranking, would require extensive discussions between stakeholders and, in our opinion, would be difficult to resolve to everyone’s satisfaction.

5.3. Overall

A reasonable evaluation of a new method is if it tells you something useful and is an improvement or refinement of an existing method. There is nothing new in the type of indicators used within the environmental footprint as they have been used individually before. The carbon footprint is now an established indicator for assessing the impact of greenhouse gases associated with a product or process but its ability to quantify environmental impact is limited. Combing the carbon footprint with other environmental indicators (pesticides, eutrophication, acidification and water) allows a wider and fuller evaluation of environmental burdens. Although emissions of greenhouse gases are of great environmental concern, other burdens are assuming greater importance with time. This has been recognised by Defra in the recent Food Matters report (Defra, 2009) which considers the introduction of environmental labels on food. The environmental footprint could form the basis of a future environmental label were it to incorporate crop yield or another productivity indicator.

Although, it will be obvious to agronomists, this study has reconfirmed that large regional differences exist with regard to crop inputs, and consequently, outputs and emissions. The difference in winter wheat environmental footprints between Sussex and Lincolnshire is considerable and although some of the differences can be explained by regional differences in soil and weather, we suggest that the environmental footprint of many crops could be reduced by disseminating basic agronomic information across different regions. Regional benchmarking of the major environmental indicators would be a good starting position. Benchmarking could consider the environmental footprint on both an area and yield basis and allow the calculation of an optimum environmental footprint for any particular crop which

SID 5 (Rev. 3/06) of 23

could then determine the region, soil type and weather characteristics which allow maximum production with minimum environmental impact.

References

Azapagic, A., Emsley, A. & Hamerton, I. 2003. Polymers: The Environment and Sustainable Development. John Wiley & Sons Ltd.

Azapagic, A., Roland, C. & Perdan, S. (Editors). 2004. Sustainable Development in Practice: Case Studies for Engineers and Scientists. John Wiley & Sons Ltd.

Barber, A. (2004). Total Energy & Carbon Indicators for New Zealand Kiwifruit Orchards: A Pilot Survey. New Zealand.

BSi. 2008. PAS2050 Specification for the assessment of the life cycle greenhouse gas emissions of goods and services. London.

Defra. 2007a. Climate change statistics. ww.defra.gov.uk/environment/statistics/globatmos/-index.htmDefra. 2009. Food Matters: One Year On. Defra, London.Hoekstra, A.Y. & Chapagain, A.K. 2008. Globalization of water: Sharing the planet’s freshwater

resources. Blackwell Publishing, Oxford.IPCC. 2006. Guidelines for National Greenhouse Gas Inventories, Volume 4. Agriculture, Forestry and

Other Land Use.Kovach, J., Petzoldt, C., Degnil, J. & Tette, J. 1992. A method to measure the environmental impact

of pesticides. New York's Food and Life Sciences Bulletin 139: 1-8.Jenssen,T. K. & Kongshaug, G. 2003. Energy consumption and greenhouse gas emissions in

fertiliser production. Proceedings 509, The International Fertiliser Society, pp. 1−28.Williams, A.G., Audsley, E. & Sandars, D.L. 2006. Determining the environmental burdens and

resource use in the production of agricultural and horticultural commodities. Main Report, Defra Research Project IS0205. Bedford: Cranfield University and Defra.

References to published material9. This section should be used to record links (hypertext links where possible) or references to other

published material generated by, or relating to this project.

Defra. 2007b. The use of environmental footprints in horticulture: Case studies. Final report of Defra project WU0114

Lillywhite, R. & Collier, R. 2009. Why carbon footprinting (and carbon labelling) only tells half the story. Aspects Of Applied Biology 95.

Lillywhite, R. 2008. The environmental footprint: a method to determine the environmental impact of agricultural production. Aspects Of Applied Biology 86:61 – 68.

SID 5 (Rev. 3/06) of 23

general enquiries on this form should be made...

Documents