effect of ecological compensation areas on floristic and breeding bird diversity in swiss agricultur

Effect of ecological compensation areas on floristic and

breeding bird diversity in Swiss agricultural landscapes

F. Herzog a,*, S. Dreier a, G. Hofer a, C. Marfurt b,B. Schupbach a, M. Spiess b, T. Walter a

a Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Reckenholzstrasse 191,

CH-8046 Zurich, Switzerlandb Swiss Ornithological Institute, CH-6204 Sempach, Switzerland

Abstract

www.elsevier.com/locate/agee

Agriculture, Ecosystems and Environment 108 (2005) 189–204

In the 1990s the Swiss agricultural policy was reformed and new environmental objectives were formulated. The aims of the

reform were to halt the loss of agro-biodiversity and to enable the spread of endangered species. As a result, the utilised

agricultural area (UAA) is now interspersed with low input ecological compensation areas (ECA), making up 13% of the UAA

(extensified grassland 90,000 ha, traditional orchards 25,000 ha, hedgerows 3000 ha, other elements 23,000 ha). To assess

whether ECA contribute to the enhancement of biodiversity, plant composition was recorded on 1914 ECA of the Swiss plateau

and 1966 territories of 27 bird species, which typically breed in open and semi-open farmland, were mapped and related to ECA.

Eighty-six percent of ECA litter meadows and 50% of ECA hedgerows were of good ecological quality and attracted wetland

and hedgerow birds. Most ECA hay meadows and traditional orchards, on the other hand, still reflected their former intensive

management with only 20 and 12%, respectively, being of good ecological quality. Hardly any benefits for grassland and orchard

birds were observed. Ecological quality of ECA was generally higher in the bio-geographical region ‘Basin of Lake Geneva and

Upper Rhine Valley’ than in the other two regions of the Swiss plateau and it was higher in the agricultural production zone ‘Pre-

alpine Hills’ than in the ‘Lowland Zone’.

# 2005 Elsevier B.V. All rights reserved.

Keywords: Agri-environment scheme; Biodiversity; Grassland; Hedgerow; Orchard; Policy evaluation; Breeding birds; Vegetation

1. Introduction

Modern, industrialised agricultural production has

boosted food security, but to a great extent it has done

* Corresponding author. Tel.: +41 1 377 74 45;

fax: +41 1 377 72 01.

E-mail address: [email protected] (F. Herzog).

0167-8809/$ – see front matter # 2005 Elsevier B.V. All rights reserved

doi:10.1016/j.agee.2005.02.003

so at the expense of the environment. In the early

1990s the increased awareness of environmental

damage caused by agriculture together with the

growing costs for the regulation of agricultural

markets led to the introduction of agri-environment

schemes. In Switzerland as in other countries, there

was an animated public debate on the cost of

government expenses for the support of agriculture

.

F. Herzog et al. / Agriculture, Ecosystems and Environment 108 (2005) 189–204190

and about undesirable effects of agricultural produc-

tion on landscapes, biodiversity and water quality.

This resulted in the Swiss agricultural and agri-

environmental policy being re-framed. A transition

occurred from a post World War II, production

oriented policy to a more comprehensive policy based

on the perception that agriculture has multiple

functions (Gunter et al., 2002). In 1996 a revised

constitutional article, which tied direct income

payments to minimum ecological management

requirements, gained a large (78%) majority in a

popular referendum.

Today, the Swiss agri-environmental policy is

comprised of three components. The cornerstone is the

fact that since 1999, farmers have to prove that they

meet a number of environmental standards in order to

Table 1

Major types of ecological compensation areas (ECA) in Switzerland, are

ECA types Area in

2002 (ha)

Low intensity hay meadows: meadows with

minimum size of 0.05 ha, restrictions on

fertilisation and mowing (late cut, specific

dates for agricultural production zones

according to altitude)

82,999

Litter meadows: meadows with minimum

size of 0.05 ha for traditional litter use,

prescriptions on mowing, no use of fertiliser

6,571

Hedges, field and riverside woods: hedges

with grassland buffers of �3 m on

both sides

2,929

Traditional orchards: standard fruit and

nut trees, mostly on grassland

24,201b

Others: extensively managed and wooded

pastures, wild flower strips and arable

fallows, isolated trees and alleys, water

ditches and ponds, ruderal areas, stonewalls,

naturally covered field tracks, species

rich vineyards

23,321

Total 140,021

a Criteria for ecological quality of the vegetation according to the b

compensation areas in agricultural landscapes (BLW, 2001). The detailed c

and Italian at http://www.bk.admin.ch/ch/d/sr/c910_14.html. The list of plab Estimated from the number of trees assuming 100 trees/ha.

qualify for area-related production subsidies (cross

compliance; Schmid and Lehmann, 2000). In 2002,

86% of the farmers – who together farm 96% of the

utilised agricultural area (UAA) – fulfilled these

requirements (BLW, 2003). The most important

measure with respect to biodiversity has been that

each farmer has to convert 7% of their farmland to

ecological compensation areas (ECA) (Table 1). The

management of ECA is regulated (late cut of

meadows, restrictions in fertilisation, pesticide use,

etc.) in order to achieve environmental goals (BLW,

1998a). As approximately 80% of the country’s UAA

is grassland (SAEFL and FOA, 2000), hay meadow

and litter meadow ECA make up the largest part of

ECA. The other types are far less important in area.

Still, namely perennial woody elements (hedgerows,

a and share of utilised agricultural area (UAA) (BLW, 2003)

Share of

UAA (%)

Criteria for ecological qualitya

8.11 Required plant indicator

species present in the plot

core area (edge excluded)

0.64 As for low intensity hay meadows

0.29 �2 m width (excluding buffer),

no invasive species, �5 shrub

or tree species per 10 m length,

�20% of thorny shrubs, alternatively

one native tree every 30 m

(stem perimeter �170 cm at

150 cm above ground)

2.43 �0.2 ha with �10 trees, 30–100

trees/ha, combination with another

ECA within ecological effective

distance (stipulated as 50 m in the

implementation of the by-law)

2.28 (Not included in the by-law and

not investigated)

13.75

y-law on the regional improvement of the quality of ecological

riteria are listed in the by-law, which is available in French, German

nt species is indicated at: http://www.blw.admin.ch/rubriken/00330/.

http://www.bk.admin.ch/ch/d/sr/c910_14.html

http://www.blw.admin.ch/rubriken/00330/

F. Herzog et al. / Agriculture, Ecosystems and Environment 108 (2005) 189–204 191

traditional orchards) are important elements of

ecological infrastructure in agricultural landscapes

(Jedicke, 1994; Herzog, 2000).

The second part of the Swiss agri-environment

scheme consists of direct payments, which have been

available for specific, voluntary environmental mea-

sures since 1993, when the ECA programme was first

introduced. Thirdly, since 2002, additional bonus

payments are granted if minimum ecological quality

standards are met and/or if farmers join a project to

link biotopes (by-law on ecological quality; BLW,

2001).

With respect to biodiversity, the political objectives

were formulated as follows (Botsch, 1998; Forni et al.,

1999):

� N
atural biodiversity should be enhanced,
� A
gro-biodiversity should be preserved (no further
extinctions but stabilisation and spreading of

endangered species).

These goals should be reached by 2005 with the

years 1990/1992 – before the introduction of ecolo-

gical direct payments – acting as a reference period.

An evaluation project was launched to assess the

programme’s effectiveness in 1996 although the first

ecological measures had already been introduced in

1993. To compensate for the late start of the evalu-

ation, which prevented the pre-assessment of the status

of agricultural biodiversity, a normative approach was

adopted to decide on the success of the programme.

The following criteria were used:

� T
he number of endangered species promoted by
ECA (this criterion is explicitly stated in the

political objectives; Botsch, 1998; Forni et al.,

1999).

� T
he share of ECA, which fulfil ecological minimum
standards as defined for the vegetation in the by-law

on ecological quality; the standards are summarised

in Table 1 according to BLW (2001). These

standards are based on a historical perception of

traditional agriculture as it was practised until the

middle of the 20th century before intensification

accelerated and agricultural biodiversity was

strongly reduced. For grassland, these standards

include not only ECA, which correspond to

traditional hay and litter meadows, but also ECA,

which can potentially reach that quality provided

that extensive management continues.

� T
he share of grassland ECA, which actually do
correspond to traditional hay and litter meadow

types as defined by species indicator lists (Dietl,

1995).

As there are no pre-defined threshold values for

these criteria (e.g. minimum share of ECA which

should fulfil quality standards), the share of ECA,

which meet quality requirements, was compared be-

tween individual ECA types. The results will allow the

policy makers to re-direct financial incentives accord-

ing to agri-environmental objectives (e.g. increase

support of ‘‘successful’’ ECA types).

In this paper we address three main topic areas:

1. S
patial implementation of ECA by farmers: does
the local topography influence the localisation of

ECA? How do ECA relate to other landscape

elements? Are there regional differences?

2. F
loristic quality of ECA: do ECA contain
endangered plant species? Which proportion of

ECA corresponds to the quality requirements of the

by-law on ecological quality (BLW, 2001) and to

traditional vegetation types (Dietl, 1995), respec-

tively? Are there regional differences?

3. S
tatus of breeding birds in relation to ECA: do
ECA favour birds and – if so – which ecological

groups of birds?

The results of surveys carried out between 1998

and 2001 are reported.

2. Materials and methods

2.1. Study regions

In 2002, 67,000 farming enterprises – mostly

family farms – farmed 106 ha of agricultural land and

540,000 ha of alpine pastures, which together com-

prised 37% of the country’s surface area. The average

size of a farm holding was 16 ha (BFS, 2002a, b; BLW,

2003).

Due to financial constraints, we limited our

investigations to the Swiss plateau mainly because

approximately three quarters of ecological payments


Fig. 1. Study regions of the evaluation of the agri-environment scheme on the Swiss central plateau. Bio-geographical regions according to

Gonseth et al. (2001). The two distinct regions ‘Basin of Lake Geneva’ and ‘Upper Rhine Valley’ are unified in one bio-geographical unit. ECA:

ecological compensation area.

go to farmers of the Swiss plateau compared to one

quarter going to farmers of mountain regions (BLW,

2003). The Swiss plateau consists of three bio-

geographical regions (Fig. 1). The central plateau is

subdivided into a western and an eastern part, which

differ mainly by the higher frequency of plant species

of fenlands in the ‘Eastern Central Plateau’. The third

bio-geographical region is composed of two spatially

distinct parts, the ‘Basin of Lake Geneva’ and the

‘Upper Rhine Valley’. They form a single bio-

geographical region because in both, similar species

and species compositions are found. In addition to the

species present in two bio-geographical regions of

the central plateau, the ‘Basin of Lake Geneva and

Upper Rhine Valley’ frequently contains plant species

of (sub-)Mediterranean origin and of the western-

European lowlands (Wohlgemuth, 1996; Gonseth

et al., 2001).

Although the differences in elevation and topo-

graphy of the Swiss plateau are relatively small

compared to the other bio-geographical regions – they

range between 260 and 960 m.a.s.l. – they can still

influence the conditions for agricultural production.

Therefore, each bio-geographical region was sub-

divided into the agricultural production zones ‘Low-

lands’, which are essentially flat and can be intensively

managed and ‘Pre-alpine Hills’, where agricultural

management is somewhat restricted by topography

(BLW, 1998b). We expected differences in plant

composition and in ECA implementation between bio-

geographical regions and between agricultural pro-

duction zones. The alpine bio-geographical regions

and the agricultural mountain production zones, where

the actual mountain agriculture takes place, were not

included in this evaluation.

Throughout the Swiss plateau, 56 study regions

(municipalities) were examined between 1998 and

2001 (Fig. 1). For the mapping of ECA and vegetation,

a stratified multistage cluster sampling was applied.

Eleven municipalities were selected in each bio-

geographical region, of which seven were located in

the agricultural production zone ‘Lowlands’ and four


in the ‘Pre-alpine Hills’. Breeding birds were mapped

in 23 municipalities, each of which had a minimum of

4 km2 of agricultural land.

2.2. ECA mapping

In all municipalities ECA were localised with the

help of local farmers, mapped and then digitised in a

geographical information system (subsequent versions

of ArcInfo). The national topographical map 1:25,000

(data status 1995/1996) with digital layers for forest,

streams and rivers and the digital elevation model

were provided by the Swiss Federal Office for

Topography (license no. DV002208.1). For each

municipality exposition, inclination and the spatial

arrangement of all investigated ECA-types except

orchards (i.e. hay meadows, litter meadows and

hedgerows) were analysed and compared to average

values of these factors for the total UAA. For each

municipality the digital elevation model was used to

classify aspect and inclination into categories. The

proportions of ECA per category of aspect and slope

were compared with the proportion of UAA in the

same categories. To analyse the average distance of

ECA and of UAA to forest and streams, the land cover

layer of the municipalities was enlarged (buffer zone

of 1000 m) and transformed into a grid of 1 m � 1 m

cell size by ESRI GRID. For each grid cell the

Euclidian distance to streams and forests were

calculated. The ECA layers were transformed to a

grid of 1 m � 1 m cell size by ESRI GRID of the same

origin as the distance grid. Overlaying the two grids

resulted in the distance for each ECA to the closest

stream and forest. The distances (ECA, UAA) were

classified into categories, yielding the proportion per

category of distance. With a pair wise t-test differences

between the distribution among the categories for

UAA and ECA were compared; the level of

significance was corrected according to Bonferroni

(Rice, 1989).

2.3. Vegetation surveys

Vegetation surveys were conducted on all ECA hay

meadows, ECA litter meadows, ECA hedgerows and

on a maximum of five traditional orchards per

municipality (selected randomly based on aerial

photographs). For each ECA grassland and orchard,

a list of vascular plant species present in the core area

(excluding the margins) was established. In ECA

hedges, woody plants as well as herbaceous plants in

the margins were recorded. Hedgerow characteristics

(share of thorny shrubs, indications for hedgerow

management), orchard characteristics (tree species,

occurrence of tree cavities, estimated age of fruit trees)

and site characteristics were also recorded. The

ecological quality or restoration capacity was assessed

by minimum occurrence of indicator species, required

shrub and tree structure and additional environmental

quality criteria (Table 1). Overall averages for the

Swiss plateau were pondered with the share of area of

existing ECA types in the investigated strata according

to government statistics (BLW, 2003). With logistic

regression analyses we investigated, in a stepwise

procedure, the effects of the bio-geographical regions

and agricultural production zones on the share of

ECA, which met ecological quality criteria. The null

hypothesis for the entire model (all explanatory

variables in the model are zero) was tested with �2

log likelihood statistics (deviance term) and the p-

value identified significant deviances from the entire

model. The GLM procedure of the statistical package

SAS (SAS Institute Inc., Cary, NC, USA) was used.

2.4. Bird mapping

Bird mapping was restricted to 37 bird species, for

which open and semi-open agricultural landscapes are

essential for survival. The species were chosen to

cover a range from widespread breeders (i.e. skylark

Alauda arvensis and yellow hammer Emberiza

citronella) to breeding birds with high habitat

requirements and very restricted breeding ranges in

Switzerland (i.e. hoopoe Upupa epops and red-headed

shrike Lanius senator). The 37 selected species

included 25 species of the Swiss Red List (four

species critically endangered, 2 species endangered,

10 species vulnerable, 9 species near threatened)

(Keller et al., 2001). Species were grouped according

to their ecological requirements, i.e. birds of open

agricultural land, birds of traditional orchards, birds of

hedgerows and wetland birds (Pfister and Birrer,

1997). Adopting the methods proposed by Luder

(1981) and Bibby et al. (1992), each region was

visited three times between mid-April and mid-June

and bird observations were localised on field maps


Fig. 2. Spatial distribution of ecological compensation areas (ECA) in 2002 in the study region of Ruswil, central Switzerland (a), share of ECA

(%) of utilised agricultural area (UAA) (except alpine summer pastures) throughout Switzerland (b). Source: BLW (2003).

Table 2

Test of spatial allocation of ecological compensation areas (ECA hay meadows, ECA litter meadows, ECA hedgerows) as compared to the entire

utilised agricultural area with respect to exposition (a), inclination (b), distance to forest (c) distance to rivers and streams (d)

(a) Exposition

Flat N NE E SE S SW W

All regions ns ns ns ns ns ns ns ns

(b) Inclination (8)

0–3 3.1–6 6.1–9 9.1–12 >12

Eastern Central Plateau ns ns s (�) ns s (+)

Western Central Plateau ns ns s (�) ns s (+)

Basin of Lake Geneva and Upper Rhine Valley ns ns s (�) ns ns

All regions ns s (�) s (�) ns s (+)

(c) Distance to forest (m)

0–10 10.1–50 50.1–150 150.1–250 250.1–500 >500

Eastern Central Plateau s (+) s (+) s (�) s (�) ns ns

Western Central Plateau s (+) s (+) ns s (�) s (�) ns

Basin of Lake Geneva and Upper Rhine Valley ns ns ns ns ns ns

All regions s (+) s (+) s (�) s (�) s (�) ns

(d) Distance to rivers (m)

0–3 3.1–10 10–50 50–150 150.1–250 250.1–500 >500

All regions ns ns ns ns ns ns ns

ns: not significant (p > 0.05), s: significant (p < 0.05), (�): ECA less frequent than statistically expected, (+): ECA more frequent than

statistically expected.


(1:5000–1:10,000). The centre of gravity of the three

observations was considered as an approximation of the

centre of the territory of a particular pair of breeding

birds, and this point was mapped and digitised. A bird

territory was allocated to a particular ECA if its centre

was within a range of 25 m of the ECA. Territories,

which were within a 25 m distance from more than one

ECA, were equally distributed between them. Con-

fidence intervals according to Bonferroni were calcu-

lated (Byers et al., 1984) to examine whether centres of

territories of ecological groups were significantly more

frequent near specific types of ECA. Significance was

tested with x2 statistics.

3. Results

3.1. Spatial implementation of ECA by farmers

As every farmer allocates at least 7% of their land

to ECA, they are spread throughout the agricultural

landscape (Fig. 2a). There are, however, differences

between agricultural production zones. In the ‘Low-

land Zone’, 11.7% of the UAA is managed as ECA

compared with 13.8% in the ‘Pre-alpine Hills’ and

16.2% in the ‘Mountain Zone’ (BLW, 2003; Fig. 2b).

The average size of ECA on the Swiss plateau

was 0.32 � 0.16 ha for the grassland types and

0.54 � 0.04 ha for traditional orchards. Hedges had

on average a length of 139.6 � 92.2 m.

We hypothesised that farmers would prefer to

allocate ECA on plots of low productivity and/or plots

which are more difficult to manage, i.e. plots which

are north exposed, steep, adjacent to forest edges or

surface water. For the Swiss plateau we tested if the

spatial allocation of the investigated ECA-types

(except for orchards) was random and thus equal to

the distribution of UAA or if farmers had certain

preferences when deciding which plot to transform to

ECA. The results are summarised in Table 2.

The statistical analysis showed no difference in the

exposition of ECA compared to that of all agricultural

land (Table 2a); there was no statistically significant

difference between bio-geographical regions or

agricultural production zones. In the steeper areas

of the ‘Eastern Central Plateau’ and ‘Western Central

Plateau’, however, ECA occurred significantly more

frequently than expected on slopes above 128 and less

often than expected on slopes between 6.1 and 98(Table 2b).

Since agricultural land next to forest edges tends to

be shaded and remote from the farmhouse, we

expected farmers to favour these areas as ECA.

ECA grasslands occurred more frequently within up to

50 m from the forest edge (Table 2c) except for the

bio-geographical region ‘Basin of Lake Geneva and

Upper Rhine Valley’ where differences between ECA

and UAA were not statistically significant.

A certain share of ECA close to streams and rivers

would provide an additional benefit for the protection

of surface water from nutrient and pesticide inputs.

The statistical test showed that in general this was not

the case (Table 2d). There were, however, strong

differences between individual municipalities. In one

particular municipality, where a comprehensive land-

scape planning programme had been conducted, all

ECA were located next to streams (results not shown).

For none of these analyses the agricultural

production zone had a statistically significant effect.

3.2. Structure and floristic composition of ECA

3.2.1. ECA hay and litter meadows

In botanical surveys of 1306 ECA hay meadows

and 104 ECA litter meadows, 453 species and 259

species, respectively, were recorded (535 vascular

plant species in total). The distribution of species

frequency was unbalanced. Only 15 plant species

occurred on more than half of the ECA meadows, the

five most frequent species being Poa trivialis, Dactylis

glomerata, Taraxacum officinale, Holcus lanatus and

Trifolium repens. Red List species (at national level)

were rare with only three endangered species (Bromus

racemosus, Carex buxbaumii, Eriophorum gracile, on

litter meadows only) and 20 vulnerable species

recorded (Table 3a and b).

On average, 20% of the ECA hay meadows

throughout the Swiss plateau fulfilled the require-

ments of the by-law on ecological quality (BLW,

2001). There was a strong variability, however,

between bio-geographical regions and agricultural

production zones (Table 4a and b). In the logistic

regression model both variables showed a significant

effect on the share of ECA hay meadows, which met

the quality requirements ( p < 0.0001 both). In the

region of the ‘Basin of Lake Geneva and Upper Rhine


Table 3

Number of plant species and of Red List species (Moser et al., 2002) recorded in the three bio-geographical regions and the two major

agricultural production zones of the Swiss plateau in ECA meadows (a), ECA litter meadows (b), ECA hedgerows (c) and traditional ECA

orchards (d)

Type of ECA Bio-geographical

region

Agricultural

production

zone

Number

of ECA

investigated

Total area

of ECA

investigated

(ha)

Number of plant species

Total On regional

Red ListaOn national

Red List a

CR RE EN VU CR RE EN VU

(a) Hay meadows Western Central

Plateau

Lowland Zone 206 67.1 235 0 1 3 5 0 0 0 3

Pre-alpine Hills 273 110.0 249 0 0 1 3 0 0 0 1

Eastern Central

Plateau

Lowland Zone 313 82.7 259 1 0 2 6 0 0 0 2

Pre-alpine Hills 163 46.7 231 0 0 4 4 0 0 0 3

Basin of Lake

Geneva and

Upper Rhine Valley

Lowland Zone 253 90.3 260 0 0 1 4 0 0 0 2

Pre-alpine Hills 98 32.9 235 0 0 2 5 0 0 0 1

(b) Litter meadows Western Central

Plateau

Lowland Zone 0 0 –

Pre-alpine Hills 0 0 –

Eastern Central

Plateau

Lowland Zone 48 22.6 200 1 0 2 21 0 0 3 10

Pre-alpine Hills 54 13.3 190 0 0 1 17 0 0 0 3

Basin of Lake

Geneva and

Upper Rhine Valley

Lowland Zone 2 0.6 33 0 0 0 0 0 0 0 0

Pre-alpine Hills 0 0 –

(c) Hedgerows Western Central

Plateau

Lowland Zone J 4.7 280

(sb 88)

1 1 6 8 0 0 1 1

Pre-alpine Hills 32 1.0 269

(sb 26)

0 0 1 5 0 0 0 1

Eastern Central

Plateau

Lowland Zone 74 7.2 279

(sb 101)

0 1 7 11 0 0 0 1


(sb 51)

0 0 3 4 0 0 0 0

Basin of Lake

Geneva and

Upper Rhine Valley

Lowland Zone 67 6.9 378

(sb 104)

0 0 4 10 0 0 0 3


(sb 57)

0 1 1 4 0 1 0 0

(d) Orchards Western Central

Plateau

Lowland Zone J 20.4 109 0 0 2 0 0 0 0 2

Pre-alpine Hills 19 9.2 86 0 0 0 1 0 0 0 0

Eastern Central

Plateau

Lowland Zone 54 38.5 88 0 0 0 0 0 0 0 0

Pre-alpine Hills 15 6.9 85 0 0 0 1 0 0 0 0

Basin of Lake

Geneva and

Upper Rhine Valley

Lowland Zone 28 9.6 135 0 0 0 0 0 0 0 0

Pre-alpine Hills 20 10.7 88 0 0 0 0 0 0 0 0

a CR: critically endangered, RE: regionally extinct, EN: endangered, VU: vulnerable; sb: shrub species.


Table 4

Share of ecological compensation area hay meadows (a), litter meadows (b), hedgerows (c) and orchards (d), which met the criteria of the by-law

on ecological quality (BLW, 2001)

Percentage Bio-geographical region Percentage Agricultural production zone Percentage

(a) Hay meadows

Swiss plateau 20.2 Western Central Plateau 16.3 Lowland Zone 17.2

Pre-alpine Hills 13.8

Eastern Central Plateau 16.8 Lowland Zone 13.5


Basin of Lake Geneva

and Upper Rhine Valley

30.3 Lowland Zone 25.3


(b) Litter meadows

Swiss plateau 81.7a Western Central Plateau – Lowland Zone –

Pre-alpine Hills –






Pre-alpine Hills –

(c) Hedgerows

Swiss plateau 50.4 Western Central Plateau 51.5 Lowland Zone 47.7








(d) Orchards

Swiss plateau 11.9 Western Central Plateau 7.7 Lowland zone 9.1

Pre-alpine hills 2.2

Eastern Central Plateau 6.6 Lowland zone 7.4




39.4 Lowland zone 33.1


For the size of the sample refer to Table 3.a Averaged over the three strata where litter meadows occurred.

Valley’ significantly more ECA hay meadows met the

quality requirements ( p = 0.0002 compared to ‘Wes-

tern Central Plateau’; p < 0.0001 compared to

‘Eastern Central Plateau’). Within the bio-geographi-

cal regions ‘Eastern Central Plateau’ and the ‘Basin of

Lake Geneva and the Upper Rhine Valley’ the ECA

quality was significantly lower in the ‘Lowland Zones’

( p < 0.0001 both). ECA litter meadows mostly

occurred in the ‘Eastern Central Plateau’ where on

average 82% met the quality requirements of BLW

(2001).

According to different levels of farming intensity,

Dietl (1995) proposed a classification of grasslands for

Switzerland, based on the presence of indicator

species. Five classes were distinguished: (1) wetlands

(Molinion, Calthion, Caricetum davallianae); (2)

Arrhenatherion s.l. (typical traditional fertile hay

meadows of the lowlands); (3) Arrhenatherion

fragments (plant communities containing some but

not all indicator species of traditional hay meadows);

(4) modern, intensively managed meadow types

(Lolium spp., Alopecurus and D. glomerata mea-

dows); and (5) a category consisting of tall herb

vegetation. The first two classes represent the target

vegetation types of traditional litter and hay meadows

(Dietl and Grunig, 2003).

Wetlands, which largely consist of ECA litter

meadows, occurred mainly on the ‘Eastern Central

Plateau’, whereas in the other bio-geographical

regions they were scarce (Fig. 3). The share of

typical, formerly widespread traditionally managed

fertile hay meadows, i.e. Arrhenatherion types from


Fig. 3. ECA meadows classified according to Dietl (1995) into five intensity types, the first two (wetlands, Arrhenatherion) being the target

vegetation types. Share in per cent of total area of ECA hay meadows and ECA litter meadows, respectively.

dry to wet performance, was highest in the ‘Lowland

Zone’ and the ‘Pre-alpine Hills’ of the bio-geogra-

phical region ‘Basin of Lake Geneva and Upper Rhine

Valley’ (31 and 37%, respectively), whereas in the

other regions it made up around 12% of the

investigated grassland ECAs. In every region we also

identified Arrhenatherion fragments which – provided

extensive management as ECA continues – may

evolve towards restored Arrhenatherion meadow

types. High intensity type meadows dominated

throughout all bio-geographical regions and agricul-

tural production zones (43–79% of ECAs, Fig. 3).

3.2.2. Hedgerows

We investigated the vegetation and structure of 317

ECA hedgerows with a total length of 44.3 km. One

hundred thirty-five shrub and 380 herb species were

recorded (Table 3c). The shrub composition in

hedgerows was similar throughout the Swiss plateau

with typical shrubs of spontaneous hedgerows and

forest edges such as Prunus spinosa, Crataegus spp.,

Rosa spp., Cornus sanguinea, Rhamnus catharticus,

Viburnum opulus, Evonymus europaeus and Acer

campestre. As in grasslands, only few endangered

species (eight at the national level) were found

(Chenopodium vulvaria, Kickxia spuria, Lythrum

hyssopifolia, Odontites vernus, Rosa majalis, Saphy-

lea pinnata, Spiraea ulmifol and Stachys annua).

Thorny bushes were observed in most hedgerows

(95%), but few of them in sufficient abundance to

create attractive habitats for arthropods and birds.

The hedgerows were evaluated according to the

criteria of the by-law for ecological quality (BLW,

2001; criteria summarised in Table 1), which aims at

enhancing the diversity of plant species and structure

in order to promote faunistic diversity. On average

50.4% of the area of ECA hedges met these ecological

standards with up to 81.9% in ‘Pre-alpine Hills’ of the

‘Eastern Central Plateau’ (Table 4c). Generally, the

hedgerow quality was higher in the ‘Pre-alpine Hills’

because more old trees occurred and the share of

invading neophytes was lower than in the ‘Lowland

Zone’. The analysis with the logistic regression model

confirmed the effect of the agricultural production

zone on the share of hedgerows of good ecological

quality for the Eastern Central Plateau ( p = 0.01),

whereas the model indicated no difference between

bio-geographical regions.

3.2.3. Traditional orchards

The vegetation and structure of 187 traditional

orchards with a total area of 108.5 ha was investigated.


Most orchards consisted of apple trees (51%),

followed by cherry trees (20%), pear and plum trees

(5% each) and by mixed stands (19%). Only four plant

species of the undergrowth were inscribed on the Red

List (Epilobium collinum, Odontites vernus, Silene

noctiflora, Trifolium montanum) (Table 3d). On

average, over all strata, 11.9% of the orchards met

the quality requirements of the by-law for ecological

quality (BLW, 2001; criteria summarised in Table 1)

(Table 4d). With 39.4% this share was highest in the

‘Basin of Lake Geneva and Upper Rhine Valley’; it

was significantly higher than in the ‘Western Central

Plateau’ ( p = 0.0007) and the ‘Eastern Central

Plateau’ ( p = 0.0008), where values were below

10%. Within bio-geographical regions, the shares of

quality orchards were in the same order of magnitude

between agricultural production zones and did not

differ significantly.

Cavities in trees are important nesting sites for

orchard birds; they were recorded in between 35 and

80% of the orchards, depending on region and zone.

On a fifth of the orchards only, there was a share of at

least 20% recently planted trees, which indicate a

periodic renewal of the stand.

3.3. Breeding birds

Twenty-seven of the 37 selected bird species were

observed breeding in at least one of the 23 study areas

(24 species listed in Table 5 and the following three

species – excluded from Table 5 because less than five

territories were mapped – eurasian jackdaw Corvus

monedula, lesser spotted woodpecker Dendrocopos

minor and melodious warbler Hippolais polyglotta).

Six species were observed foraging or passing

(meadow pipit Anthus pratensis, ortolan bunting

Emberiza hortulana, rook Corvus frugilegus, tree

pipit Anthus trivialis, whinchat Saxicola rubetra and

woodlark Lullula arborea) and four species were not

observed at all (cirl bunting Emberiza cirlus, corn

crake Crex crex, grey partridge Perdix perdix, hoopoe

Upupa epops). Species richness of birds was between

four and 17 species per study area. Overall abundance

was 13.9 territories/km2, varying between 2.6 and

34.2. Among the bird species taken into account,

skylark and yellowhammer were the most abundant,

with 5.5 and 4.9 territories/km2, respectively. Most

species, however, had less than one territory/km2.

The sampling design does not allow us to detail the

results according to bio-geographical regions nor

agricultural production zones; therefore only average

results for the entire Swiss plateau are reported.

We tested whether the centres of bird territories

were more frequent in or near ECA by comparing their

actual distribution with a hypothetical random

distribution of bird territories (Table 5). The species

were grouped according to their ecological require-

ments. Openland birds, namely skylark were sig-

nificantly less frequent than expected in or near ECA.

On the other hand, the centres of the territories of

hedgerow birds, as for example yellowhammer and

red-backed shrike (Lanius collurio), were significantly

more frequent in or near ECA. Wetland birds, namely

reed (Acrocephalus scirpaceus) and marsh warbler

(Acrocephalus palustris), were also more frequent on

or near ECA, especially on litter meadows which are

generally also of high floristic quality (Table 4c).

Amongst the orchard birds, only the green wood-

pecker (Picus viridis) was slightly more frequent in

ECA orchards.

4. Discussion

4.1. Implementation of ECA in the agricultural

landscape

Although there are regional differences in the share

of ECA of total UAA, ECA are found everywhere in

the agricultural landscape and the acceptance is almost

general. Eighty-six percent of the farmers participate

in the scheme; most of the remaining 14% are

excluded from participation for various reasons (size

of holding below minimum required, regulations on

ownership, maximum income, etc.; BLW, 1998a).

South exposition of agricultural land potentially

increases its productivity. We therefore hypothesised

that farmers would rather reserve this land for

conventional production and ECA would mostly be

north exposed. Whereas this was not confirmed in the

statistical analysis, the inclination seems to be

affecting farmers’ decision. ECA were significantly

more often than expected in the steeper areas, which

are more difficult to manage (Table 2a and b). From an

environmental point of view, a certain concentration

of ECA in steep areas makes sense, as extensive


Table 5

Bird territory centre positions of ecological species groups and individual bird species in relation to ecological compensation areas (ECA)

Typical habitat and name of species Total number

of territories

Number of territories in the sur-

roundings of ECAa

x2-statistics

Observed Expected

Open cultivated land – 68 151 45.6***

Skylark (Alauda arvensis) 756 46 129 53.4***

Quail (Coturnix coturnix) 52 7 9 0.4

Kestrel (Falco tinnunculus) 40 7 7 0

Yellow Wagtail (Motacilla flava) 12 1 2 –

Pheasant (Phasianus colchicus) 11 3 2 –

Corn bunting (Emberiza calandra) 7 4 1 –

Lapwing (Vanellus vanellus) 7 0 1 –

Traditional orchards 106 25 20 1.3

Redstart (Phoenicurus phoenicurus) 58 12 10 0.4

Green woodpecker (Picus viridis) 33 11 6 4.2*

Wryneck (Jynx torquilla) 5 1 1 –

Woodchat shrike (Lanius senator) 4 0 1 –

Grey-headed woodpecker (Picus canus) 3 1 1 –

Little owl (Athene noctua) 3 0 1 –

Hedgerows 829 293 143 157.3***

Yellowhammer (Emberiza citrinella) 598 225 102 148.3***

Linnet (Carduelis cannabina) 87 14 15 0.1

Red-backed shrike (Lanius collurio) 68 26 12 16.3***

Whitethroat (Sylvia communis) 35 13 6 8.2**

Stonechat (Saxicola torquata) 17 4 3 –

Cuckoo (Cuculus canorus) 13 6 2 –

Stock dove (Columba oenas) 4 1 1 –

Turtle dove (Streptopelia turtur) 4 1 1 –

Icterine warbler (Hippolais icterina) 3 3 1 –

Wetlands 185 52 31 14.2***

Reed warbler (Acrocephalus scirpaceus) 78 14 13 0.1

Marsh warbler (Acrocephalus palustris) 71 27 12 18.8***

Grey wagtail (Motacilla cinerea) 24 6 4 –

Reed bunting (Emberiza schoeniclus) 12 5 2 –

(–) Indicates statistics not computed because the number of expected territories is <5.a Total number of territories per bird species and ecological group as observed and as expected on the basis of the ECAs’ share of farmland

(17%, including a 25 m buffer around ECAs).* p < 0.05.

** p < 0.01.*** p < 0.001.

management of steep agricultural land tends to reduce

the risk of soil erosion and nutrient run-off.

Farmers had a clear preference for allocating ECA

near forests edges where shade reduces yield and

management options (Table 2c).

The Swiss by-law for water pollution control

prohibits the use of fertilizers and pesticides on a 3 m

buffer strip along streams and rivers and these buffer

strips would be predisposed for ECA. Table 2d

indicates that generally this is not the case, except for

individual municipalities where the allocation of ECA

was integrated in an overall planning process.

4.2. Ecological quality of ECA

4.2.1. Value systems

Assessing the ecological quality of a habitat is not

straight forward and depends on the value system and

objectives. With respect to agricultural landscapes,

Duelli and Obrist (2003) distinguish between the


objectives of: (i) species conservation (focus on rare

species); (ii) ecological resilience (focus on diversity

of species); and (iii) biological control of potential

pest organisms (focus on predators and parasitoids).

The Swiss agri-environment programme aims at

objectives (i) and (ii). The quality requirement for

objective (i) was defined as the number of endangered

species. The quality requirement for objective (ii)

could be the number of species found on ECA as

compared to control sites. This approach was applied

for the assessment of the effectiveness of ECA with

respect to breeding birds. With respect to vascular

plants, it was possible to adopt a normative approach

because the by-law on ecological quality (BLW, 2001)

provides guidelines on the target vegetation of ECA.

Thus, the results are highly relevant for the policy

maker. However, the ecological quality as defined in

the by-law is the result of a combined scientific and

political process also influenced by pragmatic con-

siderations (e.g. facilitating the control of the quality

criteria). Therefore, in addition and as a control for the

validity of this assessment, we compared the species

composition of grassland ECA with a typology, which

reflects the intensity of management.

Only very few Red List plant species were found

(Table 3) and therefore, ECA hardly contribute to the

preservation of endangered species. If this were the

only criterion to evaluate the success of the ECA

scheme we would have to conclude that its perfor-

mance is rather poor.

4.2.2. ECA grasslands

Up to 92.2% of the ECA litter meadows were found

to meet the requirements of the by-law on ecological

quality. In contrast, the share of ECA hay meadows

(which make up 59% of all ECA in Switzerland),

which met the requirements of the by-law, was as low

as 13.5% in the ‘Lowland Zone’ of the ‘Eastern

Central Plateau’ and never above 50% (Tables 4a and

5b). The differences in the botanical quality between

those two ECA grassland types were also reflected by

the distribution between the different intensity types of

grassland management (Fig. 3). In accordance to these

findings, the bird mappings showed that wetland birds

took advantage of ECA whereas the territories of birds

of open agricultural landscapes, where grassland ECA

mostly consists of ECA hay meadows, were not more

frequent on or near ECA (Table 5). The structure and

botanical quality of most ECA hay meadows still

reflected their former intensive utilisation and the late

cut did not suffice to make these usually dense stands

suitable for bird nesting. Moreover, many ECA

meadows were located along vertical structures such

as forest edges (Table 2c), which openland birds tend

to avoid. For arthropods, on the other hand, case

studies showed a more rapid reaction to the ‘offer’ of

ECA than the vegetation (Pfiffner and Luka, 2000;

Peter and Walter, 2001; Schupbach et al., 2002;

Jeanneret et al., 2003a,b,c). This mitigates the

negative assessment of ECA hay meadows and

demonstrates the necessity to investigate several

biodiversity indicator groups.

4.2.3. ECA hedgerows

Of the 35,000 ha of hedgerows in Switzerland

(BFS, 1997) only about 10% are inscribed as ECA by

farmers. This percentage is relatively low even when

considering that not all existing hedges are actually

owned by farmers. In the different study regions

between 28.4 and 81.9% of ECA hedges were assessed

as ‘quality hedges’ according to BLW (2001)

(Table 4c). The structure of the vegetation, the share

of thorny shrubs, the occurrence of dead wood and the

number of cavities in trees play an important role in

their potential attractiveness for animals (Zwolfer

et al., 1984; Baudry et al., 2000). There were

significantly more hedgerow bird territories than

expected in or near hedgerows (Table 5) and hedgerow

birds also seem to take advantage of nearby ECA

grasslands, which improve their foraging conditions.

4.2.4. ECA orchards

Between 1951 and 2001 the number of standard

fruit trees in traditional orchards has been reduced by

79% (BFS, 2002a, b). In the meantime almost 90% of

the remaining 3 � 106 trees are inscribed in the ECA

scheme but the replanting rate of orchards seems to be

insufficient to ensure their long-term existence. Only

few traditional orchards complied with the require-

ments of the by-law on ecological quality (BLW,

2001) (Table 4d) and only one orchard bird species

(green woodpecker) was found more frequently in or

near traditional orchards (Table 5). Pozzi (2004)

analysed the diversity and abundance of spiders in

traditional orchards in a case study region. He found

that they contributed to the preservation of rare and


typical spider species. Also, traditional orchards are

part of the landscape heritage in several regions of the

Swiss plateau, especially so in the ‘Basin of Lake

Geneva and Upper Rhine Valley’. They are relevant

for landscape scenery and for public acceptance of the

agricultural sector (Herzog and Oetmann, 2001;

Schupbach, 2001) and potentially beneficial for the

landscape water and nutrient balance (Herzog, 1998).

4.2.5. Regional aspects

There were significant differences between bio-

geographical regions. The ecological quality of ECA

hay meadows, hedgerows and orchards was generally

higher in the ‘Basin of Lake Geneva and Upper Rhine

Valley’ than in the other two bio-geographical regions.

This can be explained by the specific climatic and

pedological conditions. The species pool contains more

of the target species which are considered ‘valuable’ in

the Swiss context and which are therefore used as

indicators for ecological quality. Moreover, the soil

quality is generally lower and agricultural management

is therefore less intensive. ECA litter meadows almost

exclusively occurred on the ‘Eastern Central Plateau’.

There were also differences between the agricul-

tural production zones within the bio-geographical

regions. We consider that the generally higher

ecological quality of ECA in the ‘Pre-alpine Hills’

is due to higher topographical variability which limits

both the intensity of agricultural production in terms

of inputs as well as the creation of uniform agricultural

landscapes with large fields.

5. Conclusions

The Swiss agri-environmental policy has caused

significant changes in farmers’ practices, which go

beyond legal requirements, and so-called best practices.

The fact that almost each farmer has assigned 7% of his

or her UAA as ecological compensation must be

considered as a major achievement. Based on our

findings on the scheme’s effectiveness, the following

conclusions are drawn and recommendations made:

� M
ost ECA hay meadows still reflected the former
intensive management. The quality of the vegeta-

tion of 51–87% of the ECA meadows (depending on

bio-geographical region and agricultural production

zone) did not correspond to traditional hay

meadows (Fig. 3); their location and structure did

generally not enhance populations of meadow birds.

About 7–19% of the ECA meadows could

potentially restore to traditional hay meadow

composition. Farmers should be encouraged to

engage in their long-term extensive management.

� T
he vegetation of most ECA litter meadows
corresponded to the target vegetation composition

and to the requirements of the by-law on ecological

quality (BLW, 2001); breeding birds were more

frequent on or near this ECA type. ECA litter

meadows should further be supported.

� O
nly few hedgerows are actually inscribed in the
ECA scheme. On average, 50% were of good

ecological quality and hedgerows proved to be

advantageous for hedgerow birds. Additional funds

for the management of hedgerows would make this

ECA-type more attractive for farmers, help to

secure the existing hedges and at the same time

increase their ecological quality.

� T
he undergrowth of traditional orchards reflected
the intensive utilisation of these grasslands (mostly

pastures) and hardly contributed to the conservation

of floristic diversity. Only one orchard bird was

significantly more frequent in ECA orchards than

expected. Although the ECA scheme apparently

contributes to preserve standard fruit trees, the age

structure of orchard stands indicates that replanting

is insufficient. We suggest that extension activities

be concentrated on traditional orchards in order to

improve their environmental performance.

Our results are limited to the Swiss plateau and

cannot be extrapolated to the whole of Switzerland, as

there are significant differences between bio-geogra-

phical regions and agricultural production zones. A

consolidated monitoring and evaluation programme,

which is representative for the entire country is pre-

sently lacking; propositions have been made by Daniel

et al. (2003).

Acknowledgements

We thank Stephanie Aviron, Simon Birrer, Philippe

Jeanneret and Lukas Kohli for their comments on

preliminary manuscript versions, Debra Bailey for


correcting the language and Mikko Kuusaari and

Gwenaelle Le Lay for reviewing the content and

suggesting improvements. The Swiss Federal Office

for Agriculture and the Swiss Federal Office for

Environment, Water and Landscape funded part of the

work.

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