Landscape mosaic defines pesticide loading

The latest Pesticide Use Survey for grass in Scotland presented by SASA [1] continues a line of meticulous reporting and analysis by the UK’s pesticide survey teams [2]. It allows the conclusions –

  • the 2017 survey, published 2018 [1], found 3% of permanent and temporary grass was treated with pesticide, most of which was chemical weedkiller (herbicide);
  • Scotland’s lowland farming areas comprise a mix of fields, some having  no pesticide treatment (temporary and permanent grass) and others having very high pesticide treatment (arable);
  • at the scale of the landscape, both the benefits and risks of pesticides depend on the proportions and spatial configurations of crops and grass;
  • data from the EU’s Integrated Administration and Control System (IACS) for farm payments are now being used by the Agroecolgy group at the James Hutton Institute, Dundee, to estimate pesticide pressure in landscape mosaics.

This note summarises the latests SASA data, gives examples of landscape mosaics in east Scotland and argues that ‘low pesticide’ does not always imply ‘high biodiversity’.

Sheep feeding on hay, winter on the lower Sidlaw hills

Three broad categories of grass are considered in census records – permanent or long-term grass, temporary or rotational grass and rough grazing [3]. Permanent and temporary grass are both managed to support commercial grazing and offtake of hay or silage for feed [4]. Only 3% of these categories of grass was treated with pesticide in 2017 [1]. Rough grazing covers much of the higher land, is largely unfertilised and less than 0.5% of its total area was treated with pesticide [5].

Most of the pesticide applied to the 3% of permanent and temporary grass is chemical weedkiller (or herbicide). Those fields treated typically receive one herbicide formulation in a year. The three most widely used herbicides were MCPA, Fluroxypyr and Fluroxypyr/triclopyr, mainly for control of broadleaf weeds such as docks and thistles [1, 6]. Other herbicides such as glyphosate were applied over a much smaller area. The largest area treated with any formulation was the estimated 11,400 ha receiving MCPA. In total, 25 different herbicide formulations were recorded as being applied to grass in 2017, but all except the three cited above were applied to very small areas [1, Table 5 in report].

View of mixed arable-grass landscape in the north-east region

No treatment of fungal disease? In arable crops, fungicides tend to dominate pesticide usage. Yet very little of the area of grass was treated for fungal pathogens. Fungicide treatments to grass have even decreased compared to the survey in 2009 [1]. The very small area treated with herbicide and the almost negligible use of fungicide imply that most managed grass here gets no pesticide.

Questions now arise as to whether spatial groupings of grass fields create low- or zero-pesticide landscapes and whether the presence of grass among arable fields moderates the much higher pesticide applications to cereals, vegetables and potato. To resolve these questions, it is necessary to know the spatial variation in grass and arable land across the country and locally.

Distribution of permanent grass, temporary grass and arable

The categories of permanent and temporary grass co-occur with arable or ploughed land mainly in the east, but also across the central belt and to the west. Permanent grass is left without being ploughed for many years. Temporary or ‘rotational’ grass is sown, cultivated for a few years and then ploughed and sown with arable crops for a few years. The cycle is usually repeated.

The total area of crops and grass was 1,910,347 ha in the 2017 census [3], of which 31% was arable and 69% grass, but the mix of crops and grass is far from uniform from west to east (Fig. 1, bar chart).

Fig. 1 Areas occupied by crops, grass under 5 years old (grass <5) and grass 5 years old and over(grass 5(+)) in the four regions shown right with simplified boundaries. Source: Economic Report for Scottish Agriculture 2016 and data for 2017 [3].

The north-west (NW) region has, despite its large area, the least of these three categories of land. The south-west (SW) and south-east (SE) have similar total areas of crops and grass, but the south-west (SW) has very much more permanent grass (grass 5 years and over) than the SE. The NE has similar proportions of grass and arable to the SE. The regions are indicated very approximately on the map in Fig. 1 – the actual boundaries between regions follow administrative units and can be viewed online in the Economic Report for Scottish Agriculture [3].

The varying balance of grass and arable in Fig. 1 is caused mainly by climatic differences between the wetter west (more grass) and the drier east (more arable). Most pesticides are used in the east because the climate there is dry enough for commercial growing of cereals, tubers and oilseeds.

Arable-grass landscape mosaics

Starting around the year 2000, it has been possible to map the configurations of crops and grass in the landscape using data from the EU’s Integrated Administration and Control System or IACS. A previous article on this site explains the method [8].

Results to date show that patches of land in the SE and NE regions  are rarely all-arable or all-grass, but the proportions of arable and grass can differ widely between localities. Two representative landscapes are compared below (Fig. 2) as circles extracted from the much larger surrounding land mass. Each small shape within a circle is an agricultural field or a stretch of woodland. The average size of fields across the country as a whole is 7 ha, but fields under mainly arable cultivation tend to be larger than fields under grass.

 

Fig. 2 Contrasting eastern landscapes (showing differing proportions of grass (light green) and cereals (red, orange). Other colours: dark green, woodland; yellow and blue, arable but not cereal. The average field size in the country is about 7 ha.

The next step is to assign a pesticide application to each of the fields. Pesticide surveys are based on a sample of farms, then upscaled using the proportions of crops and grass in different zones around the country [1]. It is not possible therefore to assign either a total pesticide usage or an application of specific formulations to individual fields.

For the purpose of risk-benefit analysis, the likely or potential pesticide usage  in fields can be assigned from a national or regional average based on fields sampled in the survey. These averages, which we usually call ‘nominal’ values offer a reliable first estimate of the degree to which landscape mosaics differ in pesticide applications. As described in Mapping pesticide loading spring cereals are typically treated with around 5 formulations, winter cereals around 10 and potato more than 20.

The landscape to the left in Fig. 2 is mostly grass (light shades of green) but with a few clusters of cereal fields (red, orange). Most fields will therefore not be treated but the red and orange fields will be treated with herbicides, fungicides and some insecticides.

The one on the right is mostly arable, again the cereals shown in red and orange. However, even in the densest arable areas, there is some grass that will not be treated with pesticide.  There are also clusters of all-arable fields, each of which will get treated with between typically 5  and 20+  pesticide formulations annually depending on the crop. The formulations applied will differ between the crop-types.  Therefore the red-orange-yellow clusters will be treated each year with a very wide range of active substances.  (Details can be found in the Arable Crops surveys by SASA at the link given in [1].)

View of mixed arable-grass landscape in the south-east region
Management at the landscape scale – no easy solutions

As described in a related article Mapping pesticide loading, the IACS data can be used to define potential hot-spots of pesticide application in relation to defined ecological risks or the presence of non-target organisms such as wild plants and insects. Configurations of the type shown in Fig. 2 are also needed to develop advice on management of the landscape, for example in preparing ‘area-wide integrated pest management (IPM)’ or restoring biodiversity and its many positive functions. (More on this in a later article.)

However, simply manipulating pesticide treatment by altering the proportions of crops and grass at the scales in Fig. 2 will not by itself lead to enhanced or more stable farmland biodiversity. The main reason is that grass fields have come to support a different and generally lower plant biodiversity than the most diverse cropped fields. Disturbed cropland subject to ‘rotation’ or sequences of different crops has the capacity to hold a buried soil seedbank of up to 40 or 50 mainly uncompetitive broadleaf plant species, which if allowed to germinate and grow support much of the invertebrate food web in agriculture. In contrast, permanent grass has a different composition, both of its visible plant species and its seedbank.

A major obstacle to progress is that little is known of the species-composition of managed grass in the lowlands. It has not been a priority for research funding in recent decades. One thing is certain, however – most grassland today is very much less diverse than it was in the 1800s and early 1900s. Notably, legumes such as clovers and vetches have almost disappeared from managed grass, as have broadleaf (dicot) species. This unheralded decline is yet another major, long-term shift in the biodiversity of agricultural land and will be explored in the next article in this series.

Acknowledgement and credits

Contact: Geoff Squire geoff.squire@outlook.com / geoff.squire@hutton.ac.uk.

IACS analysis and geospatial mapping – Nora Quesada nora.quesada.pizarro@hutton.ac.uk and Graham Begg graham.begg@hutton.ac.uk.

Scottish Government provided funding to the James Hutton Institute to carry out the analysis of IACS data used in Fig. 2.

Sources, references, links

[1] Pesticide Usage in Scotland. Grassland and Fodder Crops 2017. By Monie C, Reay G, Wardlaw J, Hughes J. Science and Advice for Scottish Agriculture 0SASA) Edinburgh, at http://www.sasa.gov.uk/pesticides/pesticide-usage/pesticide-usage-survey-reports. Usage reports are compiled for chemical pesticides applied to crops and grass, not to livestock. See [9] for guidelines on sheep dip and other sources of pollution from animal husbandry.

[2] For Pesticide use surveys across the UK as a whole see Fera Science Limited: https://secure.fera.defra.gov.uk/pusstats/surveys/index.cfm.

[3] The latest agricultural census (2017) is summarised in the form of spreadsheets and graphs at Economic Report for Scottish Agriculture at https://www2.gov.scot/Topics/Statistics/Browse/Agriculture-Fisheries/PubEconomicReport. The full regional map is given online in the 2016 Report at https://www.gov.scot/publications/economic-report-scottish-agriculture-2016/ then navigate to ‘Geography and structure’.

[4] The designations permanent and temporary grass have changed at various times since the late 1800s. In the current statistics released by Scottish Government [3], the grass designations are ‘grass five years old and over’ and ‘grass under 5 years old’. Additional categories of ‘direct sown’ and ‘undersown’ grass, each occupying small areas, are recorded in the SASA pesticide survey.

[5] Land classed as Rough grazing in Scotland occupied 3,718,795 ha in the 2017 agricultural census which is 66% of the Utilisable Agricultural Area [see 6]. Of this total less than 0.5%, or about 14,000 ha, was treated with pesticide (sources in [1] above) including Asulam [6] used mainly to control bracken (granted as an emergency measure).

[6] For information on herbicides, e.g. MCPA http://sitem.herts.ac.uk/aeru/ppdb/en/Reports/427.htm and Asulam http://sitem.herts.ac.uk/aeru/ppdb/en/Reports/1551.htm.

[7] Most of the fungicide applied to grassland in the 2017 survey was on ‘undersown’ grass, which is usually the name given to grass sown so as to emerge and grow underneath a nurse crop such as a cereal. About 48% of undersown grass was treated and even here it was ‘for the control and prevention of disease on the nurse crop [1, page 11]’.

[8] Integrated Administration and Control System, IACS: data became available from the EU’s IACS system from around 2000. The use of IACS data is described at Mapping pesticide loading.

[9] For information on sheep dip and other potential environmental hazards from livestock farming: see the SEPA (Scottish Environment Protection Agency) web pages at https://www.sepa.org.uk/regulations/land/agriculture/sector-specific-issues.

How.. next.. for Agroecology at Hutton

The profile of Agroecology at The James Hutton Institute has evolved over the last two decades. The group has weathered repeated challenges since its millennial beginnings, but faces real threats in the uncertain relation between the UK and the EU. 

This note examines the changing sources of funding available to the Group.

Agroecology?

The word has several meanings in current usage. Agroecology at the James Hutton Institute brings a highly quantitative approach, combining experimentation, statistics and modelling, to understanding state and change in managed ecosystems [1]. It is ‘systems’ science at scales from the plant to the landscape. More widely, agroecology has come to mean forms of agricultural production that tend to balance the stores and fluxes of energy and matter between human needs and the long term future of the ecosystem.

The two meanings are not incompatible. Agroecological studies at the Hutton clearly point to a future in which ‘scorched earth’ strategies have no place. But to get to that conclusion and to design sustainable systems, we work on a range of approaches to ecosystem management that includes those reliant on severe and frequent disturbance and high inputs of pesticide, fertiliser and fuel.

Two decades of competitive funding

The funding of land-based research in Scotland has had the advantage of consistent support from Scottish government through funding to Scottish institutes, both before and after devolution. This support has enabled research groups to establish a base from which they can seek additional finance from other sources through what is commonly called ‘competitive funding’.

Fig. 1. Sequence of main competitive grants to Agroecology from 1998 to 2018: orange-red, UK sources, mainly government departments and some research council; blue, EU sources; green, joint industry-government initiatives. EU 1, EU 1* and EU 2 are explained in the text. The grey downward arrow is ‘now’.

The sequence of competitive grants awarded to Agroecology at the institute is shown in Fig. 1. Most are for 3-4 years, except a few one-year projects that tend to be exploratory. The 3-4 year grants each typically bring a few hundred thousand £ sterling to the Institute, enough to pay salaries of research leaders and technical staff. Many other grants, bringing <£50k, are not shown.

The challenges to be faced are clear. For the first ten years, the group was sustained on competitive funding awarded from sources within UK government departments and research councils. Those sources dried up unexpectedly in 2006-2007, and the group had to change tack or go out of business. New sources were found, mainly in the EU (blue bars) but also through new applied funding from industry-government initiatives (green bars) such as Innovate UK.

In 2017, Agroecology achieved unrivalled success for a small research group in securing three major, multi-partner EU grants, two of which it coordinates.  And the UK intends to leave the EU in 2019. How next!

[Read on for a short history of the first 20 years.]

UK sources of competitive funding

The Scottish coordinated programme in Vegetation Dynamics funded from 1995 provided a foundation. The first competitive grant was secured in 1998, for one year. There followed a succession of projects from UK sources, coloured orange-red on Fig. 1, mainly departments of the environment, agriculture and food (DETR, Defra, MAFF, etc.) but also research councils (NERC, BBSRC) when it was possible to team with eligible institutes from England and Wales. A couple of Scottish competitive grants are in there but not distinguished.

Topics of research included environmental risk assessment, population dynamics, gene movement in the landscape and optimal management of production systems.  These UK sources presented excellent opportunities to expand. Coupled with the Scottish base funding, they allowed appointment of research and technical staff [2].

The UK sources petered out in 2005-2006 – for various reasons, including changed priorities in UK ministries and an increasing difficulty for Scottish Institutes to gain access to UK competitive schemes. The period 2007-2009 was a low point. If the axe of external review had fallen at that time …… there would be ‘Agroecology no more’.

EU became the major source of funding from 2010

The value of European funding and collaborations became clear during the one EU (blue) grant gained among the sequence of UK grants. It was a taster of the enormous advantage that could be realised by collaborating with many partners across Europe’s diverse cultures and agroclimatic zones.

Following a major redirection of effort, the Group then secured a sequence of EU grants, each for four years (blue bars on Fig. 1), that kept the infrastructure in place and allowed development of new methods and new ideas [3]. Above all, the money enabled us to form major consortia with capability across Atlantic, Boreal, Continental, and Mediterranean climatic zones (Fig. 2), latterly extending to the Balkan.

In parallel with the attention to EU opportunities, the group also returned a series of  grants, coloured green in Fig. 1, funded jointly by government and industry in various schemes (such as Innovate UK). Generally, this ‘industrial’ funding could be aligned with the EU funding and gave a lead into new commercial areas that were to be exploited in the future.

Fig. 2. Map of Europe (European Space Agency -ESA) on which climatic zones are approximated. Arrows lead to and from Agroecology’s base,  the Atlantic maritime hub.

The EU projects were the major consistent source of money that allowed progression. Those grants labelled EU 1 on Fig. 1, with or without a *, were substantial projects in which Agroecology staff worked on the Project Management Group and led major workpackages. Those 4 marked EU 1*, were instrumental in alowing us to establish European networks in topics such as gene movement and persistence, legumes and nitrogen fixation, integrated pest management and environmental risk assessment [3].

Then in 2017, the commitment escalated

So far, members of the team had led multi-partner workpackages and served on programme management groups, but other organisations such as INRA (France) had coordinated the projects.

This changed in 2017 after running two successful bids and then coordinating two whole projects.  This was a major achievement by colleagues, especially given the small size of the group and its existing over-commitment to other work. These two large, multi-partner projects, labelled EU 2 on Fig. 1, signalled a new phase in Agroecology’s evolution [4].

They and the other existing EU project won at the same time will continue until 2020. The sheer degree of networking and organisation across Europe has risen above expectation – we are now collaborating with probably over 100 organisations – research institutes, universities and small businesses.

How next?

The degree of drive and ambition evident among colleagues  prompts the question ‘how’ not ‘what’. That the subject will continue to succeed by the efforts of such people is not in doubt.

The question of ‘how’ rests in the opportunities for funding. The EU was hard to get into for a first grant: the competition was and remains fierce. Very high standards had to be maintained when bids were led by others. Now even higher standards are expected for coordination.

The three current EU grants continue until well after the date at which the UK presently expects to withdraw from the EU: continued funding to the end of these grants has been guaranteed we believe. Colleagues are active as coordinators or partners is still more bids. Yet despite the great uncertainty over withdrawal from the EU, there is no option but to continue this emphasis in Europe …. yet at the same time to seek out additional opportunities more widely.

Continued …

There are many questions to be argued over whether small research groups should spend so much effort on bidding for new funding above what the base provides.

What does the money do? First, in our case, it provides people with work, wages, opportunity for improvement, scientific contacts in other countries, and visiting students and researchers. It enriches their scientific experience immensely.

Second, it magnifies our field and lab (but mainly field) experience by allowing us to operate consistently across many sites over several agroclimatic zones. The north-east Atlantic maritime lands in which we are based are themselves diverse, yet conclusions reached across all regions from the Boreal to the Mediterranean and Balkan have unassailable weight.

Further pages on this topic to follow –

Origins of Agroecology in the Scottish coordinated programme of the mid 1990s

What is best – hone your skills to bid competitively with all the effort that takes or lie content with base funding?

Notes

[1] The Agroecology Group became so named somewhere between 2000 and 2005 in accord with the collective wishes of its members. Its name was retained when in 2011 the Scottish Crop Research Institute became part of The James Hutton Institute. That change had no effect on the progression of funding in Fig. 1.

[2] Names of project leaders are omitted from this post because the effort depended on all staff. The first phase of funding allowed the appointment of all current senior researchers and most long-term field and lab technicians. Several colleagues who made important  contributions have now moved on, or sideways to remain in the Institute. Further details of people involved can be found on the Hutton’s Agroecology group pages and through the links below.

[3] The EU grants up to 2016 and main investigators are described briefly on these pages at The contribution of European funding.

[4] The three EU grants that began in 2017 are TRUE on legumes, DIVERSify on mixed cropping – both of which are coordinated by Agroecology – and Tomres. The links lead to respective project web sites. [Personal note – my role in EU projects more or less ended in 2016: though it was good to watch from a comfortable distance the efforts to bid for the three successful  2017 starts.]

 

 

 

 

 

Mapping pesticide loading

The detailed records of pesticide usage compiled by SASA, or Science and Advice for Scottish Agriculture [1] have been used for many years and to various ends by the Agroecology group at the James Hutton Institute. Recently the group began using the records to map the likely loading of pesticide at different scales and in relation to various features of the landscape.

The data on pesticide are collected as part of regular government survey. SASA asks a sample of farmers across the region to provide detailed returns of the crop-protectant chemicals they use on specified types of crop and grass – such as winter wheat, spring barley, potato, oilseed rape,  rotational grass and permanent grass. The active substances and the number of times they are sprayed onto fields are collated and summarised in reports, every two years for arable crops and every four years for grass.

Fig. 1. Birse’s 1971 map of agroclimatic zones in Scotland (property of The James Hutton Institute).

Productive agricultural land lies in oceanic climatic zones, mainly around the east coast – generally within the red and yellow zones shown on Birse’s 1971 map in Fig. 1 [2].

The latest survey for grass published earlier this year confirms the results of the previous survey that most managed grass grass receives very low pesticide inputs. Typically, 3% of rotational and permanent grass is treated in any year, mainly to control broadleaf weeds. Contrast this with the yearly 10 pesticide formulations applied to winter wheat and 20+ to potato.

Over much of the lowlands, crops and grass are grown together in the same landscape, thereby creating a highly variable mosaic of pesticide loading. Combining SASA’s surveys with data on the crops or grass grown in each field enables construction of a map of ‘nominal’ pesticide application based on the assumption that each farmer applies the national average pesticide for each type of crop or grass.

Fig. 2. Maps of (left) relative number of pesticide applications for each registered field (dark brown high, yellow low) and (right) an example of the data being used to illustrate spatial aggregation, in this instance the mean pesticide in 10 km grid squares (maps by N Quesada, GS Begg and GR Squire, James Hutton Institute).

The map based on individual registered fields in the east between the Moray Firth and the Borders is shown on the left side of Fig. 2. Dark brown indicates high pesticide applications (9 or more formulations per year) and light yellow 0 to 2 applications. Agricultural land in much of the rest of the country (including the uncoloured areas in Fig. 2) is classed as ‘rough grazing’ of which less than 0.5% gets any crop-protectant pesticide.

The map to the right, covering most of the country, shows how the field-by-field data can be aggregated in various ways, in this case to show average loadings in 10 km squares.

A short article describing the method was published 30 November 2018 on the James Hutton Institute’s Linking Environment and Farming LEAF web pages an extended version of which will be available on this site.

A baseline for Scotland’s lowland arable-grass

James Hutton Institute, Dundee, UK: Geoff Squire, Cathy Hawes, Gillian Banks, Linda Ford, Tracy Valentine, Mark Young, Contact: geoff.squire@hutton.ac.uk

Featured case study: Knock Farm, Roger Polson

[Under editing – subject to minor changes -18 July 2018]

Towards an Atlantic regional hub for sustainability R&D

An update on aims and progress with examples to coincide with the Royal Northern Agricultural Society’s EcoAgriTech event at Knock Farm near Huntly.

Introduction

The sustainability of food production systems and landscapes is a global priority. The lowland arable-grass agriculture of Scotland’s Atlantic coast presents a significant regional study, unique in its diversity, high yield potential and landscape complexity. The James Hutton Institute has been developing the arable-grass as an Atlantic regional R&D hub to stimulate and enable collaboration with expertise in Boreal, Mediterranean, Continental and Balkan regions across Europe.

The aims are to establish a sound baseline through a wide range of biophysical and economic indicators, define sustainable states, assess the current direction of change and where necessary initiate remedial action.  An essential part of the effort and expertise is contributed by farmers who allow access to their fields and landscapes for monitoring and experiment. Here, we summarise data collection on soils and seedbanks as a case study for Knock Farm near Huntly.

Methods

The region has been sampled and analysed since a first field survey in 2007. The structure of fields and their locality, the crops and weeds, the agronomy, invertebrates and the vegetation of field margins were examined in over 100 fields from the Black Isle to the Borders.  Soil was taken and assessed for biophysical quality, including particle size, carbon (C) and nitrogen (N) content, C:N ratio, water holding capacity, bulk density, penetrability, pH and pore space. The samples were processed to assess the buried weed seedbank – a useful indicator of field biodiversity and farming intensity. Return visits were made to selected sites to assess change over time. Methods are described in Publications.

Soil and seedbank indicators

Of the biophysical attributes measured in the surveys, those defining soil quality and seedbank diversity are among the most instructive. Soil indicators differ greatly among sites. To demonstrate the range, the data for each attribute are summarised in the form of frequency histograms, presented for two soil variables in Fig. 1. The horizontal axis gives the range of values divided into intervals (the upper limit of each is labelled), while the vertical axis shows the percentage of sites in each interval. 

Taking soil carbon (C, % by weight) for example, the highest proportion of sites occurs between 1.5 and 2.5%, but there are some very low values and a long higher tail of a few sites stretching to more than 6%. The spread shows that many soils, such as those around 2.5% are in moderately good health, but some soils have a low content below 1.5% and are in danger of erosion and loss of function, including capacity to yield. The other histogram shows water holding capacity (field capacity), higher values indicating a soil can hold more water when fully wetted and allowed to drain. During drought, crops in those fields at the lower end of the range will suffer water stress more quickly.

Fig. 1 Frequency histograms for all sites of soil % carbon and field (water holding) capacity. The arrows indicate values for fields sampled at Knock Farm. 

The seedbank of buried ‘weed’ seeds has a dual role in cropland ecology.  Too many injurious weeds are damaging to yield. Too few of the beneficial weeds limit the cropland’s ability to sustain food webs that in turn mediate essential processes such as breakdown of organic matter, nitrogen transformations, pest regulation and pollination. Arable seedbanks are generally manageable if they contain 3,000 to 9,000 seeds per square metre (of field surface to a depth of 20 cm). Below 2,000 and they tend to hold too few beneficial species. Above 9,000 and their weed burden becomes difficult to control. These numbers might sound high, but they were much higher, typically 10,000 to 100,000 per square metre, in the first half of the 20th century.

Seedbanks are usually dominated by a few species but contain others at low density.  Seedbanks that can sustain a diverse in-field food web typically contain 15-25 species, ideally in an equitable balance. 

Fig. 2 Frequency histograms for all sites of the number of plant species in seedbank samples and the number of seeds per unit field area. The arrows indicate values for fields A and B sampled at Knock Farm. Text box below gives explanation.

Case study: Knock Farm, Huntly (Roger Polson)

Two fields were sampled at Knock Farm. They were very similar in terms of soil attributes. In Fig. 1, the location of the fields on each histogram is shown by the single arrow. Fields were well above average in soil carbon and near the top of the range in field capacity. The fields also came out near the top in most other soil quality variables, including bulk density and porosity (air space). 

The fields differed in their seedbank, probably indicating either a difference in previous management or local conditions. Seed numbers of all species combined (10 to 15) in Field A were in the range 9000-12,000 per square metre and the seedbank was dominated by one species at very high density, chickweed (Stellaria media). The other, Field, B, was far less dominated: it had fewer seeds and more species, almost an ideal combination. 

Each year, weeds emerge from a seedbank but hardly ever in direct proportion to the species present. Here, Field A also had a higher density of emerged weeds in 2007, but the dominant species was annual meadow grass (Poa annua). On a subsequent sample in 2014, both Poa annua and Stellaria media were still the commonest weeds, but other species, bringing diversity to the food web, were hemp-nettles (Galeopsis species) and redshank (Persicaria maculosa). 

Conclusions and progress to date
  • Field surveys in eastern, lowland Scotland are providing baseline data to characterise an Atlantic zone hub in sustainability R&D.
  • Time trends are being assessed by measuring factors in the same locations in different years.
  • Information collected at field and farm scales is being aligned with national inventories and mapping of soil, climate and land use.
  • The baseline can be used to rate and rank fields and practices on individual holdings, as shown here for Knock Farm, near Huntly.
 Acknowledgements

The original survey in 2007 was managed jointly by TJHI and SRUC in a major project funded by Scottish Government as part of the Sustainable Crop Systems Programme 2006-2011. Soil and seedbank attributes were measured at TJHI’s laboratories. Subsequent sampling up to 2015 was also funded by Scottish Government.

Publications

Hawes C, Squire GR, Hallett PD, Watson C, Young M. 2010. Arable plant communities as indicators of farming practice. Agriculture Ecosystems and Environment 138:17–26.

Squire G R. 2017. Defining sustainable limits during and after intensification in a maritime agricultural ecosystem. Ecosystem Health and Sustainability 3; doi.org/10.1080/20964129. 2017.1368873.

Squire G R, Hawes C, Valentine T A, Young M W. 2015. Degradation rate of soil function depends on trajectory of agricultural intensification. Agriculture Ecosystems and Environment 202:160–167.

Valentine TA, Hallett PD, Binnie K, Young MW, Squire GR, Hawes C, Bengough AG. 2012 Soil strength and macropore volume limit root elongation rates in many UK agricultural soils.  Annals of Botany 110:259-270. 

Young M W, Mullins E, Squire G R. 2017. Environmental risk assessment of blight resistant potato: use of a crop model to quantify nitrogen cycling at scales of the field and cropping system. Environmental Science and Pollution Research 24:21434–21444.

Greening with decision trees

Analysis of the Report of the Scottish Government CAP Greening Group 2017. Interpretation through DEXi decision trees. Their potential in planning and implementation.

During 2017, a group of farmers, NGO representatives and scientists were asked to consider the current status and utility of Greening measures and options for an improved future system. This article is an interpretation of the group’s report [1] augmented with related discussion, including a much wider examination of CAP Greening by a team from The James Hutton Institute [2].

Concepts and ideas discussed  in the Greening group are summarised as a ‘tree’ built in a programme called DEXi, devised by Marko Bohanec at the Josef Stefan Institute, Slovenia [3]. The tree shows two main branches – one in blue in Fig. 1, covering the methods of a future CAP replacement, and one in orange showing the things that the replacement should try to improve, such as the rural economy, biodiversity and appreciation of the countryside.

 

Fig. 1 Division of the tree: the upper branch, blue, defines how to achieve a future ‘CAP’; the lower, orange, sets out the required economic, biophysical and societal status of a sustainable system.

DEXi trees such as this can be made ‘active’ and ‘worked’ to quantify, compare and rank different schemes .

The structure of the tree, explained below, is not one that the author thinks is final or complete – its aim is to summarise the report and discussion of the Greening group. The author’s preference for a more expansive and integral ‘greening’ will be argued in subsequent articles.

The main branches

The tree begins or ends, because it can work both ways, with an overall appraisal of the reform, named here ‘future sustainable’ [4]. To achieve this state, the methods of future-CAP (branch 1, its aims and incentives) and the desired states of the ecosystem that the methods are designed to achieve (branch 2, the outputs and services) both need to be satisfied (Fig. 2). There is little point in having a great system that encourages farming to achieve a desired state, but that state itself is unsustainable, and vice versa.

Each main branch sub-divides in this case into three (but it could be two or four). Branch 1 needs an overall strategy and design, then a set of assessment and advisory tools and finally a means to make it work. Branch 2 is here expressed through environmental, economic and societal features of the ecosystem. There is no unique merit in this division – branch 2 could be split into the four main ecosystem services or several Sustainable Development Goals or any other overarching frame. In fact, these sub-divisions are simply what the author felt best covered the recommendations of the CAP Greening group – but they could easily be altered.

Fig. 2 Primary branches of the tree into aims & incentives and outputs & ecosystem services, each of which then subdivides into three. Each group of three ‘leaves’ determine the value of a ‘node’ through  a utility function.

Each ‘box’ on the tree – named an attribute in decision tree terminology – can be defined by its contribution to an overall sustainable state. In practice, attributes tend to be rated on a three- to five-point scale, e.g. high, medium or low.  As the tree is worked rightwards, each box is seen to depend on several other boxes. For example, outputs-services depends on environment, production and societal attributes, and if all these three are rated high, then the branch is also rated high. But what happens if environment is high but societal low. The result is then decided by a utility function. The rules governing each utility function are set by the operators or group of people working the tree.

This working of the utility function is the core of DEXi decision trees. In practice, the function can be changed during a round-table meeting and the result compared. How to do this will be covered in another article. This one will set out the main structure of the tree.

Aims and incentives – how to achieve the desired ecosystem state

The part of the overall tree in blue in Fig. 1 and named as branch 1 in Fig. 2 consists of three main boxes split into further boxes, shown here as a set of hierarchical levels (Fig. 3). Altogether 5 levels are shown from left to right.

 

Fig. 3 Branch of the decision tree covering aims and incentives of a ‘future CAP’.

One of the sub-branches is described for illustration – the central one ‘strategic / design’. Discussion emphasised the need to have a broad but defined framework in which future-CAP would operate and the need for it to be holistic, i.e. covering a wide range of land management outcomes and their interactions, and inclusive, allowing a range of people both managing and affected by the system to have a say. The framework should be ‘enabling’, which means letting managers decide how to achieve the best result, and both flexible and sensible, allowing managers to vary decisions depending on the season and locality.

Other needs that recurred in the discussion were for greater professional training for farmers and advisers and a set of new metrics by which the achievements were judged. The Result-based approach to agri-environment schemes offers one way to devise such new metrics [5].

As before, utility functions determine the value of an attribute from its dependents. If two proposed schemes are being compared, for example, each would be ranked as to how well they satisfied all the attributes in the boxes. For ‘Advice and training’ to rate high, both ‘enhanced extension services’ and ‘professional development’ would need to rate high (and so on).

Features of a sustainable system

The lower branch in Fig. 1 – branch 2, outputs / services – defines features of a sustainable system. ‘Outputs’ refers to the economic and other products supported by the system while (ecosystem) ‘services’ refers to the functions of storage and cycling of solar energy, water and nutrients among different parts of the system. Generally on this web site, economic products will be regarded as another flow of energy and materials, no different in principle from the main element cycles, but here they are distinguished.

The central sub-branch of 2 is about agricultural production. It is of course highly simplified but shows some of the main topics discussed. Central to the whole debate is the balance between how much comes off the farm and what farming gets for it. The general opinion was that other stages in the quality chain from yield to consumer get more of the benefits than accrue to the farmer. So there is little point in having a profitable crop if the balance is unfair, and to achieve fairness will need buy-in from people and government.

 

Fig. 4 The branch of outputs-services dealing with agricultural production.

Another sub-branch is named ‘environment’ (Fig. 5), which again shows some of the main topics  examined. For example, ‘landscape complexity’ would be ranked according to how well the landscape supported a diversity of plants and animals. Connectivity, including managing across types of landscape, featured highly in discussion. For landscape complexity to rank high, several landscape types, here illustrated by upland high-nature-value farmland and lowland farmland, would each have to each rank high, but then the connectivity between them would also have to be high.

Under ‘reduce adverse impacts’, losses & pollution would need to include all the various processes that lead to a low carbon footprint and therefore high sustainability, while ‘soil & food webs’ would be broken down into many compartments, not just the general one indicated.

Fig. 5 The branch of outputs-services dealing with ‘environment’.

The final branch under 2 deals with ‘societal health & wellbeing’ in terms of food and nutrition, landscape, a sense of place and employment in the countryside (Fig. 6). Taking one of these for illustration, food and nutrition divides into diet and also local production – the latter to capture those aspects of locality and provenance that are considered increasingly important by many people. For ‘food and nutrition’ to rate high, therefore, it will not be enough that the food is nutritious, but it must also be produced with regard for and least damage to nature, and from a short quality chain, rather than one that goes round the world and back.

Fig. 6 The branch of outputs-services dealing with societal health and wellbeing.

The operation of a decision tree

The first task in designing a decision tree is to set out the main variables – the ‘attributes’ in decision tree terminology and the relations between them. The structure of the tree and its attributes shown in Fig. 2 to 6 are based on topics that emerged in the Greening report and related discussion [1]. The author finds that doing this in itself helps appreciation of the range of issues that need to be considered.

For the tree to operate as a decision-aid, each box has to be quantified on a scale, typically 1 to 5  or 1 to 3, or high-medium-low, which defines the degree to which the attribute contributes to a sustainable state. Then the utility functions (see Fig. 2, 3) have to be set that determine the value given to an attribute depending on the value of the two or more that that feed into it. This might sound a little complicated, but in DEXi software, a simple tree such as this, once built, can be worked in an hour of round-table discussion.

DEXi decision trees are mainly used for comparison, so it would now be time to compare schemes, such as two proposed alternatives for future CAP greening. (Before doing that, the author needs to do further checks to consider whether the structure is ‘right’ for the purpose.)

In the meantime, the full branch 2 is laid out in Fig. 7. Even in simplified form, it involves a lot of attributes – but this reflects the complexities of managing land for many outputs and ecosystem services.

Fig. 7 Branch 2 combining Fig. 4, 5, 6 and showing the utility functions (ovals) that need to be in place to make the tree operational.

Putting numbers on the attributes

As stated, each box or attribute has to be defined on a scale indicating its contribution to a sustainable production system. Decision trees much larger than this have been constructed for comparing integrated pest management schemes (DEXiPM) and production ecosystems. One developed by the author and collaborators is named DEXiES – DEXi for Ecosystem Services. It has hundreds of attributes, most well quantified through years of research in the landscapes of eastern Scotland.

DEXiES has been used to compare high- and low-input cropping and is being extended to HNV grazing. Ratings applied to each attribute are mostly taken from hard quantitative data. For example, in lowland cropped agriculture, soil carbon below 1.5% might be classed as ‘low’ for sustainability, 1.5-3% as medium, 3-4% as medium-high and above as 4% high.

While each of the attributes in the DEXi tree shown here could in principle by quantified in a similar way on a three or five point scale, many of them will not have been thought about in this way – ‘beauty of nature’ for example. Yet experience has shown that a group of people, of diverse backgrounds and interests, could after some debate, rate and rank a greening support scheme in terms of its contribution to sustainability.

Sources, links

[1] Report by the CAP Greening Group available on the Scottish Government web site at CAP Greening Group: Discussion paper.

[2] A major, detailed review of CAP Greening was undertaken by The James Hutton Institute. Findings are detailed in summary and multi-part report available to download from the Scottish Government web site at CAP Greening Review.

[3] Decision trees, multi-attribute modelling and DEXi software at Marko Bohanec’s web site DEXI: a programme for Multi-Attribute Decision Making.

[4] The definition of what is meant by sustainable will be examined in detail elsewhere. Growing cereals and tending stock have been  practiced here for 5000+ years and there is no reason in principle why they should not continue for this period into the future. Within the bounds of arguments around CAP greening,  ‘sustainable’ means any practice that contributes to such a continuation, which relies on healthy soil and an ecologically well functioning landscape.

[5] For an introduction to Result-based approaches, see Regenerative agriculture : short supply chains.

Author/contact: geoff.squire@hutton.ac.uk


Acknowledgements

The author (G R Squire) was funded by The James Hutton Institute to take part in discussions of the CAP Greening group [1]. The contribution of a chapter by G R Squire & C Hawes to the Hutton Greening report [2] was funded from the Hutton’s Ecological Sciences group budget.

Again, thanks are to Marko Bohanec for devising DEXi and making it available free of charge.

Posts, articles and blogs on this curvedflatlands web site (including this one) are prepared in the author’s own time.

 

 

Regenerative agriculture : short supply chains

Comment on the meeting Farmers and Nature, SNH, 18 May 2018. Inspiring examples: holistic, diverse, innovative. Current support unfitting. Long supply chains need disrupting. Result-based payment a way forward. B for A and A for B.

Inspiring examples were heard today of a commitment to farming and wider land management by five different people and enterprises [1]. The aim of this SNH-sponsored meeting – Farmers and Nature: promoting success and looking forward, 18 May 2018 – was to get people to share their experiences of managing land for the long term and for a range of economic and environmental outputs. All five speakers agreed that just taking from the land was not feasible, but that ecological regeneration and maintenance were essential for a future. There was little prosaic description of what not to do. Rather, the day was a set of inspired personal accounts by people operating outside the expected norms of agricultural management and long food supply chains.

Fig. 1 Contrasting lowland landscapes, fields mapped in colour: greens representing various types of grass, orange cereals. Prepared by Nora Quesada and Graham Begg for the Living Field web site.

Diversity of landscape and land use (Fig. 1) means that no one set of prescriptions can be applied to gain environmental benefit in farmland. Flexibility is needed to allow local adaptation to solve local problems, as was heard.

Speakers were: David Aglen, Balbirnie Home Farms [2], specialising in combinable crops, veg and potatoes, grass for suckler cows and forestry; Bryce Cunningham, Mossgiel Farm [3] producing ‘non-homogenised milk, by Ayrshire cows grazing the historical pastures of Robert Burns’ and in doing so disrupting the established the long and convoluted supply chain for milk processing and marketing; Lynn Cassels, Lynbreck Croft [4] producing hens, pigs, cattle and bees and also planting trees, in what many would class as difficult land and climate; Roger Polson, Knock Farm, Hunty [5] running a mixed organic enterprise with suckler cows, breeding ewes, livery horses and spring crops; and Teyl de Bordes, Whitmuir Estate, near Selkirk [6], creating opportunities and support for a wide range of plants and animals in mixed farmland. Links to their work and presentations on the day via YouTube can be found near the bottom of the page [2 to 6].

The speakers saw themselves as far from the mainstream. It was not just that they thought themselves on the fringes, but that their neighbours and peers thought they were. Yet to me their philosophy and practices are examples of what will be central to a sustainable future. They are innovators, not complying with what is expected of farmers and crofters in the early 21st century. It was encouraging also to see some disruption of the long supply chains that force farm profits down and the decouple land from the consumer. 

Fig. 2 Some of the topics at the meeting, from general characteristics of a managed ecosystem, through products, methods and biodiversity, to criteria for support, payment and targeting. A for B is Agriculture for Biodiversity and B for A is Biodiversity for Agriculture (not presented in this form but highly relevant, see text below).

Common threads

Several general threads recurred among these examples, brought out both in the talks and in discussion (Fig. 2). One was the need to manage land holistically and over time and space rather than concentrate on one product that satisfies immediate economic demands. Most of the farms and crofts managed a range of saleable products and all farmed for the long term, despite having to overcome physical and sometimes economic hardships in the short term. ‘Work with nature not against it’ was the recurrent message: a hackneyed phrase some may think, yet true nevertheless. In the concepts discussed in these web pages, ‘working with nature’ implies managing multiple channels for the balanced flow of natural resources to soil, plants and animals [7].

Another was innovation – re-thinking how to do things. Farming did this in a big way during the Improvements era in the 1700s and in the Agricultural Expansion Programme in the late 1940s. In both instances, change was needed to overcome stagnation and reverse decline. Examples presented here included sowing tramlines to hinder surface wash after rain, and so  slowing the erosion of soil and loss of fertiliser as pollutant, and encouraging nitrogen-fixing legumes back into grass swards. 

Hardly innovations, you might think. But just look at the areas of compacted mush around most farm gates, and next time you see a mud-on-road sign, imagine where the mud came from; and then look at the imports of nitrogen and plant-protein to Europe due much to the cumulative loss over the last 150 years of home-grown legume pulses and forages. You can imagine also that some of the practices would have been seriously debated at  farmer-scientist meeting in the 1750s – running sheep on winter wheat when grass offered poor pasture was one, with little stated detrimental effect on the wheat (Balbirnie).

Support and conditions for agri-environment schemes formed a third thread (Fig. 2, lower box). Schemes were too inflexible, too prescriptive, for example in terms of dates that things should be done by,  and schemes rarely confirmed that a desired result had been achieved. Payment for result, specified in terms of populations and other ecological states was preferred and would ensure that public money led to a demonstrable, beneficial change.

And a fourth was the need to disrupt or bypass existing, mostly long, supply chains whose complexity determines, often obscurely and perhaps from thousands of miles away, what must happen on the farm, while the grower and manager has limited reward and control. The solution is to replace the long chain with a much shorter one from field and farm to consumer in one or two intermediate steps that involve retaining the production and marketing processes within the enterprise (Fig. 3). The experiences of Mossgiel Farm are a lesson. 

Fig. 3 Diagram of production and quality chains: production is buffered by operating across several different enterprises (F1, F2, etc.) that are interconnected in terms of the flow and sharing of resources over seasons and landscape; the short quality- or supply chain keeps processing and sometime sales within the enterprise (upper large box), adding value to the product and control to the grower, after bypassing an existing long chain. Design of supply chains is a main part of the EU project TRUE [9].

Result-based payment for agri-environment works

Teyl de Bordes introduced some examples of Result-based schemes in Europe in which farming is paid for delivering specified environmental benefits. Kirsten Brewster, from SNH, who organised the meeting and Teyl de Bordes since wrote a summary of six Results-based pilots. Here is an extract from their introduction. 

Result Based Agri-environment Payment Scheme (RBAPS) pilots “Results-based” is a term used to refer to agri-environment type schemes where farmers and land managers are paid for delivering an environmental result or outcome, e.g. number of breeding birds, or number of plant species in grasslands, with the flexibility to choose the management required to achieve the desired result. 

All agri-environment schemes are of course designed to deliver environmental results. However, what distinguishes a ‘pure’ results-based scheme, is that payments are only made where a result is achieved, making a direct link between the payment and the achievement of defined biodiversity outcomes (or other environmental results) on the ground. Focusing payments on achieving results encourages farmers to use their knowledge and experience to decide how to manage the land in a way that benefits biodiversity alongside farming operations. In so doing, results-based payment schemes may lead to an enhanced awareness of the importance of biodiversity conservation and protecting environmental resources as part of the agriculture system. http://ec.europa.eu/environment/nature/rbaps/articles/1_en.htm

The report by Brewster and de Bordes gives descriptions and links for each of 6 pilot studies and is downloadable as a PDF [8].

A for B and B for A

A distinction not discussed specifically at the meeting but one that is highly relevant to the design of future support, joins Agriculture (A) and Biodiversity (B) in two directions [10]. A for B is where agriculture, either inherently or by alignment, fits its methods and management to support certain life forms such as rare plants, invertebrates or birds. B for A is where essential life forms have to be maintained in a good functioning state for agriculture to continue sustainably. Examples of B for A include microbial transformations in the soil and the broadleaf weed (= wild plant) flora supporting predatory organisms that suppress pests.

Most existing schemes and support operate A for B, but in doing so almost exclusively, they do little to encourage the sustainability of agriculture.  A topical example is the argument around legumes such as peas in CAP Greening. Peas bolster a wide range of ecological processes – N-fixation, allowing a diverse dicot weed flora and enriching the habitat mosaic – yet the main and possibly only purpose of pea crops in greening measures is to be in the ground at a certain date in summer.

Whatever weighting is given to A for B and B for A, most of the ecological processes operate at scales well beyond the field. Such is the diversity of land use in the lowlands (e.g. Fig. 1) that landscapes of only a few km diameter may need specific measures. Flexibility therefore and payment for results, not blanket prescriptions, should be the basis of future support.

References, links

[1] Farmers and nature: promoting success and looking forward. Click the following links for Agenda and Speakers and the Presentations.

[2] David Aglen, Balbirnie Home Farm. Web: http://www.balbirnie.com/people. YouTube video of presentation:  Regenerative agriculture at Balbirnie. 

[3] Bryce Cunningham, Mossgield Farm. Web: mossgielfarm.co.uk Presentation on Youtube: The challenges of breaking the mould. 

[4] Lynne Cassels, Lynbreck Croft, south of Grantown-on-Spey. Web: https://www.lynbreckcroft.co.uk. Presentation on YouTube: A croft for the future

[5] Roger Polson, Knock Farm Presentation on YoTube: Managing Knock, a holistic approach. 

[6] Teyle de Bordes, Whitmuir Estate: Twitter: https://twitter.com/whitmuir1?lang=en. Presentation on YouTube: Recording nature on the farm. 

[7] Crops, grass and management open or restrict channels through which energy and nutrients flow to sustain a managed ecosystem’s various parts. See Crop Diversification at the Living Field, also [9]. Diversity of practice is the key – maintaining  to the soil and the wider food web of both invisible and visible biodiversity. Narrow the diversity and a single product might prevail, but the system fragments.

[8] Result Based Agri-environment Payment Scheme (RBAPS) pilots: K Brewster and T de Bordes, 31 May 2018. Click to download PDF BrewsterdeBordes-resultsbasedagrienvtrials.

[9] The EU H2020 TRUE project is actively developing short supply chains for legume-related crops and products. the project has much in common with many of the the sentiments of this meeting. More on TRUE on these web pages at Transitions to a legume-based food and agriculture where there are also links to the TRUE web site.

[10] The concept A for B and B for A (A = Agriculture, B – Biodiversity) which draws a workable distinction that could be introduced to future support, has been widely promoted by the agroecologist Paolo Barberi from the University of Pisa.

Acknowledgements

Scottish Natural Heritage organised the meeting. Contact: Kirsten Brewster, Kirsten.Brewster@snh.gov.uk. Kirsten Brewster and Teyl de Bordes provided access to their article on Result-based schemes, with thanks.

This article is an offshoot of work on crop diversification and food quality chains in the EU H2020 TRUE project based at the James Hutton Institute, Dundee. Views are those of the author, Geoff Squire: geoff.squire@hutton.ac.uk.

Crop diversification at the Living Field

The Living Field project will be exploring in 2018 the history, methods and value of diversifying crops and cropland. An Introduction is given on the Living Field’s web site at Crop diversification which explains why diversification matters, what it does for the sustainability of an ecosystem, its general decline in cropland and possibilities of restoring it. The Living Field articles will run in parallel to accounts of diversification on the Hutton Institute’s farms.

A wide range of crops and other useful domesticated and wild plants have been grown in the Living Field garden over the past 15 years. Starting with the cereals, for example, the Garden has grown emmer wheat, one of the first crops to be domesticated in the fertile crescent, and also spelt and bread wheats.

Cereal or corn crops also include barley, both old landraces and modern varieties, oat, rye and maize. Rice and millet were tried but did not appreciate the temperature. Cereals are shown to the left on the collage below, reproduced from the Living Field web site.

Other main groups include grain and forage legumes, medicinals and herbs, dye plants, tubers and vegetables. Micro-habitats have also been created and maintained – wet ditch and small pond, hedges and trees, meadow. Each supports a specific  flora.

Because of limits to space, not everything can be grown in all years, but in any summer, typically 200 plant species can be found. The garden is profiled on the Living Field’s web site at garden/living-exhibits.

 

Transitions to a legume-based food and agriculture

A summary with diagrams and photographs of an invited talk at the recent Conference on Advances in Legume Science and Practice organised by the Association of Applied Biologists in Glasgow 21-22 March 2018. Topics at the meeting covered a wide range of experience and disciplines from crop physiology, nutrition, molecular and traditional breeding, symbioses, landscape processes and food security.

Background – summary

Our invited presentation on Transitions to a legume based food and agriculture [1] introduced the aims and approach of the EU TRUE project, notably its central matrix consisting, first, of the quality chain from production through to markets and consumption, and second, sustainability, assessed through  economic, societal and environmental indicators.

The argument runs as follows. (A) Crops and their management alter the flows of energy and matter to various functions in the managed ecosystem. (B) Legume crops and forages have unique roles in channelling energy and matter to crucial functions related to soil quality, the nitrogen economy, pollinators and the production of plant protein. (C) To achieve a balanced and sustainable system, different types of crop, including legumes, need to be grown in planned configurations, whether within fields as mixtures, in  sequences or rotations and in spatial mosaics in the landscape. Practical designs need to consider those configurations that achieve the desired combination of functions.


Fig. 1 Faba beans Vicia faba: young crop, plant in flower, pods and fresh beans, and (small squares l to r) dried beans, flour, shelled split beans and bran.

Increasing legume production and output can be designed and managed in three stages. First, the area grown with existing legume crops such as field bean (Fig. 1)  can be increased with no change to the existing system. Second, the existing system can be modified – but not fundamentally changed – through (for example) mixed cropping of legumes and cereals, rhizobial inoculation of legume seed and  new legume products. Third, the system can be changed completely, with new crops, biotechnology and methods and untried configurations.

The presentation concentrated on  stage 1, but related work in Agroecology at the Hutton is already advancing in stage 2 though experimentation with crop mixtures, rhizobia and new products such as bread, beer and tofu made from beans [2].

Diversifying agriculture using grain and forage legumes

The flows of energy in production systems are investigated through a chain of effect linking interventions, such as agronomic management and choice of crop, through biota, including crops, to ecological processes which in combination satisfy (or not) desired higher level outputs [3].

The main crops in temperate Europe today are managed so that most of the energy is channelled to grain, oilseed or tuber yield (Fig. 2). In consequence,  other channels have been closed, or at least severely restricted, leading to long term declines in farmland wildlife and soil quality. Ultimately, such losses will feed back to limit economic output itself.

Fig. 2 The flow of energy in a winter cereal is concentrated into resource capture by the crop, then formation of yield and product, at the expense of trophic functions and soil.

The solution is to diversify the production systems of the region, in effect opening and regulating channels to other functions.  The diagram in Fig. 3 offers a highly simplified depiction of the wider balance of flows that should be realised in a forage legume.

Fig. 3 The flow of energy in a legume forage is distributed across a range of functions, notably N-fixation and trophic activity, e.g. through invertebrates.

The scope for diversification is being examined in this way for the case study of lowland Scotland. Grain legumes, mainly peas Pisum sativum and beans Vicia faba have been present from the neolithic and bronze periods and a wide range of forage species have been tried and grown over the millennia. Grains and forages are therefore being quantified as to their effect on flows such as represented in Fig. 2 and Fig. 3. Species are then modelling alone and in various spatial and temporal combinations to find optimum states.

Much can be learned from the way legumes and other crops have been grow in in the past, including in-field mixtures, often broadcast from a single ‘bag’ of mixed seed, such as mashlum, and temporal sequences, in some of which the legume and non-legume overlap (Fig. 4). Fields and sequences then combine to give additional properties at the scale of the landscape.

Fig. 4 Examples of crop diversification used traditionally in the region: B is a legume and A another crop (e.g. a cereal, root, oilseed, grass); C is an in-field mixture, such as mashlum, D a blocked, in-field mixture where the crops are separated, Ea a sequence or rotation, Eb a sequence in which some crops overlap in time (e.g. nurse crops and undersowings) and F a spatial configuration in a landscape.

The main problem facing the study was uncertainty in the locations within the region in which legumes appeared historically. However, crop census data, beginning in the mid-1800s is being examined to get the missing information.

First census of the mid-1800s

Legumes became integral to both crop sequences and forage mixtures in the Improvements era after 1700, but while some records suggest legumes occurred  1 in 4 years [4], there is little hard data on the areas grown with them compared with cereals such as oat and barley.

The 1700s and 1800s witnessed a phase of innovation and trialling of both grain and forage legumes, but for reasons that will be explored elsewhere on these pages, most forage legumes dropped out of mainstream usage with the exceptions of clovers and vetches, while grain legumes were reduced to various forms of pea Pisum sativum and bean Vicia faba.

The census of crops and grass in 1854 carried out by the Highland Society, covered most of Scotland and initiated a period of regular crop censuses which have proved invaluable in charting the phasing in and out of different crops. Data on the main crops [5], summarised for each of the old counties of Scotland (current up to to 1890), were transcribed from the 1854 records. Data were available for peas, beans and vetches: as an example, that for vetches is shown in Fig. 5, where the area of the circles, each representing an old county, indicate the relative area occupied by each crop. The circle out to the north-east represents Orkney and Shetland.

Fig. 5 Distribution of the vetches crop in 1854, sown areas represented by circles centred on the old counties of Scotland, superimposed on current administrative areas.

Beans occupied the largest area, followed by vetches and peas which covered similar areas. Most of the crops would have been grown for animal feed. Their combined areas were small, about 5% of that grown with cereals. Other sources specify that mixed forages, such as red clover, ryegrass and plantain, were also grown extensively, but no records are available of their composition and coverage. One of the recurring deficiencies of agricultural census is the classification of mixed forages as ‘grass’.

The distributions of vetches (Fig. 5) and peas were similar, both concentrated in the east and today’s central belt, but extending both south-west and north to Orkney and Shetland. That of beans was more concentrated in the east and centre.

Various crop census after the 1880s continued to show a similar distribution. When peas and beans were distinguished as to whether they were intended for human and animal consumption, those for human occupied a more restricted area in the east of centre.

Grain legume coverage today

Going forward 160 years, IACS data – from the EU’s Integrated Administration and Control System [6] – allows more precise definition of the current area grown with grain legumes.  There is still no data for grass-legume forages which must all classified under one or other of the forms of ‘grass’. Four types of grain legume are reported,  in decreasing order of area – beans for animal consumption, peas for human and for animal consumption, and least, beans for human consumption.

The total areas grown today are even smaller than the combined area of legumes in the 1850s. Maps of legume distribution after 2000 are in preparation. Examples  can be seen at the Living Field post Can we grow more vegetables? and further analysis of changes over time will be given later in these pages. However, the combined areas of the four legume types recorded tend to remain <2% and in some years near 1% of the total cereal acreage.

Low inclusion of legumes in a dynamic production ecosystem

The main conclusion so far is that grain legumes (pulses) were minor components of agriculture in the mid-1800s and have remained minor. Yet many aspects of the the crop and grass production systems in the region have been far from stable. For example, ‘root’ crops, mainly swede and turnip, covered large expanses in the late 1800s, but are relatively minor now, while of the cereals, oat was dominant in the 1800s and early 1900s but  supplanted by barley and now occupies less than 10% of the cereal area.

Recently, other crops have risen to much greater coverage than the legumes, notably winter wheat and oilseed rape in the later part of the 1900s. During all these changes, grain legume areas remained small or decreased.

One of the questions being examined is why legumes have occupied such low acreage in the region and whether and where they could be increased. Investigations of the phenomenon are continuing but one reported contribution is a greater reliance historically on clover and other legume forages for soil fertility.

There seems no particular reason, however, due to limitations of soil or climate, for the restricted area grown with legumes today within the eastern and central ranges shown in Fig. 5. Nor should it be assumed that increases will come only from existing crops. In response to CAP Greening measures, small fields of assorted legumes have appeared in the region.

That in Fig. 6 comprised three species of clover, the well know red Trifolium pratense and white Trifolium repens species, but also an unusual one, crimson clover Trifolium incarnatum which was once tried as a forage at these latitudes. A few plants of sainfoin were seen near the edge of the field, but it was not certain they were sown as part of the mixture.

Fig. 6 Legume forage, mainly of white, red and crimson clover: (top l c’wise) the field, young and older flowering head of crimson clover, sainfoin (image from plant in the Living Field garden) and  plants in an approx 0.5 m width of field (images by curvedflatlands).

Assessment by multi-attribute decision modelling

Opportunities for expanding the area of existing grain legumes are now being examined. It should also be possible to quantify potential savings of mineral nitrogen fertiliser and pesticide as the legume area is increased. The IACS data again provides the wherewithal, allowing us to assess not only which fields contained grain legumes in any year, but also which other crops were grown in the same fields in years before and after the legume. With knowledge of the crops grown in each field, nominal attributes can be assigned based on the pesticide and fertiliser applied to each crop as quantified from national surveys.

Each field can then be given a nominal agronomic ‘intensity’.  The reduction of intensity due to the substitution of an existing crop with a grain legume can then be calculated, as can the trade offs in the areas and output of other crops and products such cereal grain. The four current grain legumes offer plenty of scope for substitution, since some are grown with high-input crops, mainly winter wheat and potato, while others are grown with short-term grass and spring cereals.

Placing a value on each system, and then comparing systems, is facilitated by multi-attribute decision models (MADM) built in DEXi software [7]. A  part of the ‘tree’ structure of the current MADM is shown in Fig. 7. The interventions are shown to the right. They affect in turn the biota and ecosystem processes that determine a higher-level attribute, in this case the N loss in water leaving a field. The full MADM will include the wide range of attributes determining the economic, environmental and societal contributions of production systems.

Fig. 7 Part of a decision tree or multi-attrbute decision model built in DEXi software showing the way interventions combine in effect to influence field-scale attributes, in this case loss of nitrogen (N) in water.

Sites for expansion of legumes are therefore being selected on the basis that (a) they lie within an area, soil and climate in which grain legumes are or have been grown, and (b) they have a balance of crops very close to those fields that already include legumes in the crop sequence.

The aim is to quantify the benefits of legume expansion for the purpose of informing government policy and encouraging food and agriculture to use and grow more legumes. While concentrating on the grains at this stage, there is no reason why the approach cannot be extended to forages such as those in Fig. 8. More widely, the results will form a comprehensive study in the EU TRUE project of an approach to define long term trajectories of legume-based production systems and to extend those trajectories across Europe and farther afield.

Fig. 8 Legume species historically trialled in the region as forages: (top l, c’wise) sainfoin, milk vetch, kidney vetch, tufted vetch and white melilot,all grown in the Living Field garden (images by www.livingfield.co.uk)

Acknowledgement of funding

The main work summarised here and presented at Glasgow was funded as part of the EU TRUE project.  Background knowledge of the maritime production system of lowland Scotland was acquired with funding from Scottish Government (Rural and Environment Science and Analytical Services Division). The authors are based at The James Hutton Institute, Dundee UK.

Sources, references

[1] Squire GR, Iannetta PPM. 2018. Transition paths to sustainable legume production. Aspects of Applied Biology 138, 121-130.  Squire GR, Quesada N, Begg G, Iannetta P. 2018. Transition paths to sustainable legume production. Invited presentation at Advances in Legume Science and Practice, Association of Applied Biologists Glasgow UK, 21-22 March 2018.

[2] Links to bean beer on the Hutton website – Feed the world, help the environment and make great beer. Link to ‘tofu’ make from beans on the Living Field web site – Scofu: the quest for an indigenous Scottish tofu. See also Feel the Pulse.

[3] Squire GR 2017. Defining sustainable limits before and after intensification in a maritime agricultural ecosystem. Ecosystem Health and Sustainability, 3:8, DOI: 10.1080/20964129.2017.1368873

[4] Wight, A. 1778-1784. Present State of Husbandry in Scotland. Extracted from Reports made to the Commissioners of the Annexed Estates, and published by their authority. Edinburgh: William Creesh. Vol I, Vol II, Vol III Part I, Vol III Part II, Vol IV part I, Volume IV Part II. All available online via Google Books. Note from GS: Wight’s journals of his travels through the agricultural regions of Scotland present an unrivalled account by a farmer of the state of agriculture in the Improvements era.

[5] The agricultural census of the Highland Society, 1854, summarised by:  Thorburn T 1855. Diagrams, Agricultural Statistics of Scotland for 1854. London: Effingham Wilson. The Living Field web site has more on Thorburn  at Thorburn’s Diagrams.

[6] Integrated Administration and Control System, IACS on the EU web site.

[7] Decision trees, multi-attribute modelling and DEXi software at Marko Bohanec’s web site DEXI: a programme for Multi-Attribute Decision Making.

Contact: geoff.squire@hutton.ac.uk

 

 

Dundee sweltering in tropical heat

Early 2018 and Dundee’s waterfront is shaping well. The various cafes, restaurants and bars are gearing up for the opening of the V&A museum later in the year and locals will be dusting off their sun hats in readiness for long evenings dining by the waterside. Yet now in March that seems improbable. The winter 2017-18 has been colder than usual, temperature persistently below and around zero for months.

But which Dundee can we see here in these photographs? Not quite the Dundee as we know it – the one 7 miles from the Living Field garden [1], even with the tall ship and strange looking building by the waterfront … and the heavy cloud about to drop its load of water.

No. This place is somewhere warmer. A full-grown palm tree gives it away, and then the dark, flat line of a mangrove forest, half in the water. Mangroves couldn’t grow by the Tay, not before some serious warming. This is not cold, wet Dundee at 57N but a warm and monsoonal Queensland at 17S.

Looking back to Cairns waterfront (top), a line of mangrove forest (lower left) and palm

We were out from Cairns,  looking back towards the waterfront from a boat  to Fitzroy Island, named by Captain Cook after a member of the nobility, not Robert Fitzroy, the eminent meteorologist who captained the HMS Beagle that took Darwin on his voyage round the world [2].

Fitzroy Island

Fitzroy Island lies in the inner Great Barrier Reef, a small island, surrounded by warm water that supports vibrant corals and fish within easy snorkelling distance from the beach. The corals and sea life were astounding, and one of our party even swam with a wild turtle.

The island rises from the shore to a rocky peak over a couple of miles, forming a gradient of soil depth and exposure over which the land plants  varied according to their needs and capacity to survive. Pandans and casuarina fringed the  beaches, the dense forest behind merging into dry woodland and scrub on the higher land in the centre of the island.

Fire had blackened much of the vegetation on this higher land, yet adaptation to periodic burning was evident in the form of leafy shoots emerging from singed turf and dead-looking stems.

From Fitzroy to the mainland, large ‘cricket’ and shoots emerging from fire damaged trunk

The Great Barrier Reef is under threat, notably through bleaching of the coral [3]. Plastic also has its insidious effect here as in many places. The seas round the island looked fairly clear of it. The wind and tides brought a few pieces of waste onto the beaches, but they were being picked up and binned by visitors.

Even here

The problem here is not so much the large mass of waste being washed up on the beaches, as happens in parts of the West Highlands of Scotland for example. The reef is habitat to six of the world’s seven marine turtles.  If a single piece of plastic is ingested by a turtle, it is unable to function and floats on the surface, where unless rescued, it weakens and dies.

Turtles  can live for many decades but the Green  Turtle, for examples does not breed before 45 years [4]. Its populations – though showing no evidence of decline – are said to be  imbalanced towards females, a change attributed to increasing temperature in the nest.

A turtle sanctuary and rehabilitation centre on the island and on the mainland at Cairns looks after damaged animals, removing the plastic by feeding them until the stuck piece passes through and then nursing them until they are strong enough to be released [4]. To be rescued, a floating turtle has to be seen by a passing boat, and one sympathetic to its plight. For every one rescued, many others are likely to die.

The Great Barrier Reef and Scotland’s coasts therefore share more than primal beauty and a claim to wildness. The millions of bite-sized plastic pieces on the Scottish beaches referred to in the Living Field article Colours of Silverweed [5] are of a size to be swallowed by a turtle. It’s almost a relief that the plastic bits managed to find their way to our coasts, and settle themselves for a while among the shingle.

Neither place can do much to stop the plastic. The origins of most of it are many thousands of miles away. Even if the entry of new waste into the seas was reduced on a global scale, which is unlikely to happen for decades, the plastic already there will still circulate, get washed up or be eaten. Despite some complacency that the problem is soon solvable [6], all that can be done at the point of receipt is to continue limiting its damaging effects.

A long period of habitation

There is geological evidence that Fitzroy Island and other similar islands were once connected to a mainland until rising sea levels towards the end of the last Ice Age cut them off. This is another north-south connexion since the effects of the melting of ice covering northern Europe were to raise sea levels  here and around the world [7].

People had been living in Queensland for tens of thousands of years before that time. The mainland and the island would have been part of the same land mass. Improbable as it may seem to us in Europe, there is evidence that the people have kept alive the memory of the rising sea level through their spoken traditions [8].

Dead coral washed up on a beach, Fitzroy Island
Sources and further information

[1] The Living Field Garden is located at the James Hutton Institute, near Dundee, and is a place to study the crops and wild plants, past and present,  of lowland Scotland: www.livingfield.co.uk. The new V&A museum is sited by the Tay estuary in the centre of Dundee.

[2] The island had aboriginal names before James Cook named it FitzRoy in 1770. Naturalists and meteorologists are likely to know another FitzRoy – Robert Fitzroy (1805-1865) – as the captain of the ship HMS Beagle that took Charles Darwin on his voyage round the world. Robert FitzRoy was also a pioneering meteorologist, whose name replaced Finisterre in the Shipping Forecast in 2002. (Met geeks will have stayed awake to hear the first ‘Fitzroy’!) For general information on the island, try the Queensland Government web site on Fitzroy Island National Park.

[3] Great Barrier Reef: for background and research, see ARC Centre of Excellence for Coral Reef Studies, and a YaleEnvironment 360 article published 2017 A close-up look at the catastrophic bleaching of the Great Barrier Reef. The ARC web pages described other harmful effects of plastic on the Reef’s ecology.

[4] Information on the Green Turtle is given at the GBR Marine Park Authority’s web site. The Cairns Turtle Rehabilitation Centre describes the many ways that turtles can be damaged by human-made objects, including getting tangled in nets and being hit by boats, as well as by ingesting plastic and other waste.

[5] Colours of Silverweed [link available soon] is a Living Field article, describing the truly astounding amount plastic pieces accumulating on some of Scotland’s finest beaches, coves and inlets; and also what people are trying to do to remove it.

[6] Several newspaper articles and posts towards the end of 2017 implied that if action is taken now by governments across the world then the problem of plastic waste would disappear. One such was a leader in The Times newspaper of October 6 2017 with the title Rubbish Dumped and the strapline “The world’s oceans are being choked by plastic, but they will recover quickly if governments work together to stop it reaching the open sea”. Here, ‘recover’ and ‘quickly’ need to be reconsidered. There is no short term solution.

[7] Current predictions of sea level rise in the 21st century are compared with the much greater disturbances towards the end of the last Ice Age in an information piece by the Great Barrier Reef Marine Park Authority at Impacts of Sea Level Rise on the Reef. There is also a link on their web site to further information on ‘Marine Debris’.

[8] For example, see the following article in the online journal The Conversation Ancient Aboriginal stories preserve history of a rise in sea level.

[9] Views on the origins and distinctness of some of the peoples of the Queensland rainforest are highly contentious. See the article by Peter McAllister in The Weekend Australian, January 2011 – The ‘short mob’ goes back a long way. The 2002 article by Keith Windschuttle and Tim Gillin can be viewed with footnotes and references at The Sydney Line.

 

New EU TRUE project holds first meeting

Fantastic news that one of our new EU-funded H2020 project is getting underway. The inaugural meeting was held in Edinburgh, 19-21 April 2017. Around 50 people attended from all EU partners.

The project is coordinated by Pete Iannetta from Agroecology at the Hutton. The aims and methods of the various Workpackages were aired and discussed during two full days. A great feeling among partners of delight that the project would be funded and of looking forward to several years of intense collaborative effort ahead.

Here is the first group photograph.

Project description to follow …..