In addition to scientific considerations, entirely practical aspects must also be borne in mind when implementing the indicator system on a farm. Essentially, the four cate-gories of the BioBio indicator set are measured using three mutually complementary approaches (Figure 4.2):
• Habitat diversity indicators are obtained via habitat mapping at farm scale;
• Species diversity indicators are obtained by specific field-recording methods;
• Crop- and livestock genetic diversity indicators and farm management indicators are obtained through inter-views with farmers.
German Case Study: Mixed Farming System
Located in southern Germany, the Tertiary Hills of Lower Bavaria form part of the Alpine Foothills. This region is typical of intensively managed areas, with mixed far-ming systems (arable land, grassland and forests) and an
increasing number of organic farms. Milk is the main pro-duct of all of the surveyed dairy farms, but all sell grain too.
Number of farms surveyed: 8 organic, 8 non-organic Average farm size: 61 ha
Average N-Input: 215 kg/ha
Average energy input: 456 kg fuel equivalents Total number of habitat types: 14
Total number of plant species: 211 Total number of bee species: 34 Total number of spider species: 110 Total number of earthworm species: 11 Total number of crop species: 29 Total number of crop varieties: 140 Total number of livestock species: 1 Total number of breeds: 2
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ART-Schriftenreihe 17 | September 2012 3939 The indicator campaign starts with the selection of the
farms. Depending on the purpose of the campaign, selec-tion criteria must be carefully applied in order to ensure that the sample is representative. The farmer is then con-tacted and an initial general interview is conducted, dur-ing which the farmer’s consent, other necessary informa-tion, and a map of the farm should be obtained.
The map defines the area whose habitats are to be mapped. The selection of plots for species sampling is based on the habitat map, with one plot per habitat type being selected at random. This means that species sam-pling can only begin once habitat mapping is complete. In BioBio, data recording in its entirety took place within a year, but spreading the data recording over two years is also an option. Whilst vegetation can be recorded shortly after habitat mapping and selection of plots is available, arthropod sampling must be conducted three times – in
Figure 4.2: BioBio indicator measurement starts with contacting the farmer, who provides a map of farm boundaries. These boundaries delimit the extent of the habitat mapping. One specimen of each habitat type is then randomly selected for species recording. According to weather conditions spider and bee sampling can be combined. Farm interviews and habitat mapping yield indicators at farm scale. Species are recorded at plot level and then scaled up to farm level. The survey concludes with a detailed farm interview on the genetic diversity of crops and livestock, and on farm management.
the spring, summer, and late summer – in order to cover the entire season and record both early species and those emerging later. Depending on the region, the first sam-pling round should possibly be done at about the same time as the habitat mapping, although this would lead to constraints in terms of the availability of labour and how quickly the field campaign could be conducted. Spreading the recording over two years would resolve this conflict.
On arable farms, however, and owing to crop-rotation dy-namics, the habitat map will change – at least in part – from one year to another, and would require updating.
The field campaign is concluded by a farmer interview, during which the parameters are recorded which are needed to compute indicators for genetic diversity and for farm management. See Dennis et al. (2012) for practical advice on implementing a field campaign.
2:1 - 2 volle Textspalten - Frutiger 16 pt 2:1 - volle Textspalte - Frutiger 16 pt
Fa rm s el ec tion
Vegetation
plots Bee
transects Spider
sampling Earth-sampling worm
Bo un - da rie s
Farm level species indicators
Fa rm m ana ge m ent ind ic at or s G en et ic div er si ty ind ic at or s Plot
selection Upscaling
Habitat mapping:
Habitat diversity indicators
Farmer interviews:
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The BioBio Indicator system
References
Dennis P., Bogers M.M.B., Bunce R.G.H., Herzog F. & Jean-neret P. 2012. Biodiversity in organic and low-input farming systems. Wageningen, Deliverable 2.2 of the EU FP7 Project BioBio. ISBN 1566-7197. ALTERRA Report 2308. http://www.biobio-indicator.org/deliverables.php EEA, 2007. Halting the loss of biodiversity by 2010:
pro-posal for a first set of indicators to monitor progress in Europe. European Environmental Agency, Technical Re-port 11/2007. Available at: . http://www.eea.europa.eu/publications/technical_re-port_2007_11 [Accessed 16/03/ 12].
EC, 1985. Commission Decision of 7 June 1985 establishing a Community typology for agricultural holdings (85/
377/EEC). . http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=
CONSLEG:1985D0377:20030523:EN:PDF [Accessed 23/
02/12].
IRENA, 2005. Agriculture and environment in EU-15 – the IRENA indicator report. European Environmental Agency, EEA Report 6/2005. Available at: . ht tp: // w w w.eea.europa.eu /publications /eea _ re -port_2005_6 [Accessed 16/03/12].
Hungarian Case Study: Semi-Natural Low-Input Grassland
The case-study area is situated in Central Hungary bet-ween the Danube and Tisza rivers. The region forms part of the Homokhatsag High Nature Value Area, its lands-cape being a result of natural phenomena and human activity. Regulation of the Tisza and Danube rivers in the
19th century resulted in secondary alkaline pusza land-scapes. The Homokhatsag is characterised by an abun-dance of wildlife in connection with traditional ranching known as tanya farming. All of the farms surveyed can be classified as low-input farms.
Number of farms surveyed: 7 organic, 11 non-organic Average farm size: 170 ha
Average N-Input: 50 kg/ha
Average energy input: 140 kg fuel equivalents Total number of habitat types: 58
Total number of plant species: 384 Total number of bee species: 100 Total number of spider species: 163 Total number of earthworm species: 8 Total number of crop species: 15 Total number of crop varieties: 34 Total number of livestock species: 2 Total number of breeds: 8
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ART-Schriftenreihe 17 | September 2012 4141 Habitats are an important component of biodiversity in
their own right, as well as providing possible indicators of biodiversity at the species level. Monitoring habitat diver-sity at the farm scale starts with habitat mapping. The farm habitat map forms the basis for generating habitat indicators, and is also required for selecting plots for spe-cies recording. At the farm scale, habitat indicators pro-vide information about the composition of on-farm habi-tats, such as their richness, diversity and percentage cover. We have identified eight habitat indicators which as a set reflect the composition of the farm, and to some extent its potential for hosting wild species.
5.1 What is a farm habitat?
A habitat is an area with relatively homogeneous environ-mental conditions, occupied by plants and animals that are adapted to those conditions. On farmland, the term ‘habi-tat’ is sometimes associated with ‘semi-natural habitats’ or elements of ‘ecological infrastructure’. Wild species also occur in fields of crops, however, and some wild species such as ruderal plant species or seed-feeding birds are even specifically adapted to these environmental condi-tions. Farm habitat indicators should therefore also relate to arable- crop fields, sown and permanent grasslands, in-tensively managed vineyards and orchards, etc. At the other end of the spectrum, they must also account for less intensively managed parts of the farm such as marginal grasslands, hedgerows, or grazed forest (Figure 5.1). The BioBio method for measuring biodiversity indicators there-fore starts by establishing a habitat map of the entire farm, i.e. the utilised agricultural area (UAA) that is man-aged by a specific farmer. The farm is defined as the legal / economic unit owned or rented by the farmer. Spa-tially, farm fields are not necessarily adjacent to each other
Figure 5.1: Farm habitats range from intensively managed crop fields (a), to linear features such as hedgerows (b), to extensively managed marginal grasslands (c). Photos: (a) G. Lüscher, (b) G. Brändle, (c) S. Buholzer, all Agroscope
but can be quite far apart, depending on the historical evolution of farming in the region in question.
The boundaries between farmed and unfarmed land can sometimes fluctuate. They can be specifically defined in given regions to ensure the inclusion of all habitats poten-tially affected by farm activities. In BioBio the extent of the farm relates to the UAA, and in addition to agricultural fields also comprises:
• Hedgerows, lines of trees, shrubby, grassy and herba-ceous strips, water margins, stone walls managed by the farmer;
• Grazed forest (even if not legally part of the UAA);
• Small woods (<800 m2);
• Aquatic habitat (<800 m2).
The following, however, were excluded:
• Farmhouses and gardens;
• Large ungrazed forests (>800 m2), even if managed by the farmer (since this represents a different economic activity);
• Shrubby habitats (>800 m2);
• Nature protection areas if no longer part of the UAA – even if managed by the farmer;
• Commonly grazed lands such as summer pastures or out-fields (Switzerland, Norway), out-bye (northern England), and ffridd (Wales), that cannot be assigned to a specific farm. The fodder produced (and consumed) on this land, however, must be estimated and included in the calcula-tion of a number of farm management indicators;
• Aquatic habitats (>800 m2).
a) b) c)
5 Habitat indicators
Debra Bailey1, Felix Herzog1, Marion Bogers2, Gisela Lüscher1, Wendy Fjellstad3
1Agroscope Research Station ART, Zurich, Switzerland
2Alterra, Wageningen, The Netherlands
3Norwegian Forest and Landscape Institute, Ǻs, Norway
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Habitat indicators