Bulgarian Vegetation Database: historic background, current status and future prospects

Abstract

For geographical and historical reasons, the Bulgarian vegetation is quite diverse. In the past and up to the beginning of the new millennium, vegetation studies have been conducted in the country basically following the dominance approach. At the end of the 1990s, however, an initiative was started to collect new field data according to European floristic-ecological standards. In 1999, the Bulgarian Vegetation Database (GIVD ID EU-BG-001) was established to collect available data for getting a better insight in the di-versity of Bulgarian vegetation. The database uses TURBOVEG software and is located in the Working Group for Vegetation and Habitats in the Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia. In September 2010, this da-tabase contained 5,901 relevés, most of them related to grasslands. The major part of the data has been collected after 2000. The geo-graphic distribution of the field data over the country is uneven. Most of the data are derived from particular projects and gathered at locations with a relatively undisturbed environment. Altogether, thirty authors have contributed to the field sampling. Some 25.5% of the relevés were taken from the literature. It has been estimated that some additional 2,900 relevés can be derived from the literature and unpublished sources. For the purposes of the database, a full list of expected syntaxa for Bulgaria has been prepared.

Full text

In: Dengler, J., Oldeland, J., Jansen, F., Chytrý, M., Ewald, J., Finckh, M., Glöckler, F., Lopez-Gonzalez, G., Peet, R.K., Schaminée, J.H.J. (2012)
[Eds.]: Vegetation databases for the 21st century. – Biodiversity & Ecology 4: 141–148. DOI: 10.7809/b-e.00069.
141
Long Database Report
Bulgarian Vegetation Database: historic
background, current status and future prospects
Iva Apostolova, Desislava Sopotlieva, Hristo Pedashenko, Nikolay Velev & Kiril Vasilev
Abstract: For geographical and historical reasons, the Bulgarian vegetation is quite diverse. In the past and up to the beginning of the
new millennium, vegetation studies have been conducted in the country basically following the dominance approach. At the end of the
1990s, however, an initiative was started to collect new field data according to European floristic-ecological standards. In 1999, the
Bulgarian Vegetation Database (GIVD ID EU-BG-001) was established to collect available data for getting a better insight in the di-
versity of Bulgarian vegetation. The database uses TURBOVEG software and is located in the Working Group for Vegetation and
Habitats in the Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia. In September 2010, this da-
tabase contained 5,901 relevés, most of them related to grasslands. The major part of the data has been collected after 2000. The geo-
graphic distribution of the field data over the country is uneven. Most of the data are derived from particular projects and gathered at
locations with a relatively undisturbed environment. Altogether, thirty authors have contributed to the field sampling. Some 25.5% of
the relevés were taken from the literature. It has been estimated that some additional 2,900 relevés can be derived from the literature
and unpublished sources. For the purposes of the database, a full list of expected syntaxa for Bulgaria has been prepared.
Keywords: classification; phytosociology; plant community; relevé; sampling; vegetation survey.
Received: 5 October 2010 – Accepted: 26 May 2011 – Co-ordinating Editor: Joop H.J. Schaminée.
Introduction
The first systematic phytosociological
studies in Bulgaria were carried out in the
early 1950s (Velchev et al. 1989). They
have been conducted basically by re-
searchers from the Institute of Botany,
Bulgarian Academy of Sciences. During
almost half a century, the intensive field
work has resulted in the accumulation of a
relatively large amount of data (Apos-
tolova & Slavova 1997). The information
collected reflects the rich biodiversity of
vegetation types in the country. Up to the
1990s, nearly all phytosociological stud-
ies in Bulgaria have been based on the
dominance approach. This was a reflec-
tion of the Russian Phytocoenological
School, introduced in the country for his-
torical and political reasons. The Braun-
Blanquet approach for describing Bulgar-
ian plant communities was applied by few
researchers only, coming from abroad like
Horvat et al. (1937), Soó (1957), Simon
(1958), Michalik (1985, 1990) and
Mucina et al. (1985, 1990).
Since 1994, phytosociologists in Bul-
garia started to apply more systematically
the Zurich-Montpellier School (Braun-
Blanquet 1964). The workshop organized
in 1994 by the Department of Phytocoe-
nology and Ecology at the Institute of
Botany can be regarded as a starting
point, leaded at this time by Tenyo
Meshinev. Zdenka Neuhäuslová from the
Institute of Botany at the Czech Academy
of Sciences was invited as a guest lector.
The necessity for transforming the ex-
isting Bulgarian vegetation classification
into the Braun-Blanquet system forced
our vegetation scientists to intensively
collect new relevés in different regions. In
the same period, several countries have
built their own phytosociological data-
bases, which encouraged the work in Bul-
garia (e.g. Brisse et al. 1995, Ewald 1995,
Mucina et al. 2000, Wiser et al. 2001,
Chytrý & Rafajová 2003, Hrivnák et al.
2003, Dengler et al. 2006, Janišová &
Škodová 2007, Lájer et al. 2007,
Hegedušová 2007). The development of
the software package TURBOVEG (Hen-
nekens & Schaminée 2001) has facilitated
the storage of collected relevés worldwide
and has strongly enhanced vegetation
classification, large database analyses
(e.g. Ozinga et al. 2004, Botta-Dukát et al.
2005, Dúbravková et al. 2010), and other
vegetation studies, for example on plant
invasions in different vegetation types
(Chytrý et al. 2005). A comprehensive
overview of vegetation databases in
Europe has been provided by Schaminée
et al. (2009). It reports on the existence of
more than 4 million vegetation plot re-
cords of which more than 1,800,000 are
stored electronically. This situation facili-
tates an easy exchange of information for
large-scale scientific and applied vegeta-
tion research.
The aim of our paper is to provide in-
formation about the national Bulgarian
Vegetation Database as a virtual part of
vegetation data banking in Europe.
Historical notes for Bulgarian
vegetation database building
At the 1994 workshop of the European
Vegetation Survey in Rome, the TUR-
BOVEG software has been accepted as
the international standard management
system for vegetation relevés (Schaminée
& Hennekens 1995). In June 1999, a copy
of TURBOVEG was provided by Stephan
Hennekens, which actually was the start
for building up a national vegetation data-
base.

Biodiversity & Ecology 4 2012
142
The species list was prepared based on
Kozhuharov (1992) for the vascular plants
and on Petrov (1975) and Natcheva &
Ganeva (2005) for the bryophytes. The
list includes all accepted names of the
Bulgarian flora down to level of subspe-
cies. Some hybrids are included, espe-
cially for the genera Hieracium and Men-
tha. A large number of synonyms is added
and the species list is updated at a regular
basis.
With regard to the database, about 700
original relevés were collected. Important
input of additional data was given by the
National Grassland Inventory Project
(Meshinev et al. 2005). As a result of this
inventory, some 1,800 relevés were in-
cluded in the database. A significant part
of the relevés was collected during the
PhD studies of D.S. (2008) and K.V. and
N.V. (both unpublished). During 2001–
2010 there has been a very effective col-
laboration with colleagues from Masaryk
University, Brno, Czech Republic. Sub-
stantial datasets were collected in moun-
tain and lowland wet meadows (Hájek et
al. 2005, Hájek et al. 2008).
In 2009, a new field was added in the
TURBOVEG database for the UTM grid
system used in Bulgaria. With the help of
Stephan Hennekens, it became possible to
compile and export distribution maps of
relevés without precise latitude/longitude
information.
TURBOVEG offers the possibility to
export vegetation data for analyses in
other software tools like JUICE (Tichy
2002), CANOCO (ter Braak & Šmilauer
2002) and PC-ORD (McCune & Mefford
1999). We apply these software packages
in our regional studies that provide reli-
able tools for consistent data analyses.
GIVD Database ID: EU-BG-001
Last update: 2012-05-30
Bulgarian Vegetation Database
Scope: Sample plots including full species lists with quantitative estimates and header data. The information collected so far includes only
grasslands.
Status: [NA]
Period: 1949-2010
Database manager(s): Iva Apostolova (iva.apostolova@gmail.com)
Owner: Vegetation and Habitats Research Group
Web address: [NA]
Availability: according to a specific agreement
Online upload: no
Online search: no
Database format(s): TURBOVEG
Export format(s): TURBOVEG
Publication: [NA]
Plot type(s): normal plots
Plot-size range: 4-100 m²
Non-overlapping plots: 5,901
Estimate of existing plots: [NA]
Completeness: [NA]
Total plot observations: 5,901
Number of sources: 20
Valid taxa: [NA]
Countries: BG: 100.0%
Forest: [NA] — Non-forest: [NA]
Guilds: all vascular plants: 100%; bryophytes (terricolous or aquatic): 20%; lichens (terricolous or aquatic): 2%
Environmental data: [NA]
Performance measure(s): cover: 100%
Geographic localisation: GPS coordinates (precision 25 m or less): 13%; small grid (not coarser than 10 km): 14%; political units or only on a
coarser scale (>10 km): 73%
Sampling periods: 1940-1949: 0.9%; 1950-1959: 3.0%; 1960-1969: 4.6%; 1970-1979: 1.8%; 1980-1989: 0.2%; 1990-1999: 10.9%; 2000-2009:
75.0%; 2010-2019: 0.9%; unknown: 2.5%
Information as of 2012-07-18; further details and future updates available from http://www.givd.info/ID/EU-BG-001
Current database status
The database structure follows the stan-
dard header items of TURBOVEG, but
additionally several new items were in-
cluded in order to safeguard information
collected in different projects. ’Code‘, for
instance, refers to the original and unique
identity of the relevé according to the
field protocol. ’Erosion’ reflects visual
estimation of the process in an easy-to-
apply nominal scale (not eroded, slightly
eroded, heavily eroded). ’Locality‘, ’Lati-
tude‘ and ’Longitude‘ are related to the
location of the relevé. ’Geology‘ provides
information on the bedrock types. ‘Soil
depth’ indicates whether the soil depth is
up to 10, 25 or more than 25 cm. The field
’Pasture’ contains information about the
existence and intensity of grazing animals
in four steps (no grazing, low, moderate
and high grazing intensity), while the
field ’Mowing‘ indicates the presence or
absence of this management regime
through a simple ‘yes’ or ’no’. There are
also fields for ‘pH’, ‘Conductivity’, ‘Hu-
mus’ and ‘Total nitrogen’ for data ob-
tained by particular analyses. In most
cases, the sample plot size is 16 m2 which
is according the recommendations of
Chytrý & Otýpková (2003).
At the beginning of September 2010,
the Bulgarian Vegetation Database con-
tained 5,901 relevés. Most of them are
new and collected during the last decade
by researchers of our working group. The
sample plots were selected according to
the standards as given by various Euro-
pean vegetation scientists (Braun-
Blanquet 1964, Westhoff & van der
Maarel 1973, Mueller-Dombois & Ellen-
berg 1974, Dengler et al. 2008). Exactly
1,491 relevés are from published papers
(Velchev 1962, 1971, Drazeva 1963,
Ganchev & Kochev 1962, 1964, Ganchev
1963, Ganchev et al. 1964, 1971, Bondev
1966, Kochev 1967, Stanev 1977a,
1977b, 1977c, 1980, Meshinev et al.
1994, 2000, Roussakova 2000, Tzonev
2002, 2009, Tzonev et al. 2008). The
relevés included in the database are re-
corded by 30 authors. The period of
relevé sampling is indicated in Figure 1
showing that the active data collecting is
still going on. Relevés made before the
year 2000 are mostly originating from
literature.

In: Dengler, J., Oldeland, J., Jansen, F., Chytrý, M., Ewald, J., Finckh, M., Glöckler, F., Lopez-Gonzalez, G., Peet, R.K., Schaminée, J.H.J. (2012)
[Eds.]: Vegetation databases for the 21st century. – Biodiversity & Ecology 4: 141–148. DOI: 10.7809/b-e.00069.
143
Table 1: Diversity of classes in the Bulgarian vegetation. To the right, numbers of known alliances and associations are given.
Class
All.
Assoc.
Zosteretea
?
?
Ruppietea maritimae
?
?
Thero-Salicornietea strictae
1
3
Juncetea maritimi
1
1
Saginetea maritimae
?
?
Festuco-Puccinellietea
4
8
Crithmo-Staticetea
1
1
Cakiletea matitimae
1
1
Honckenyo-Elymetea arenarii
1
3
Ammophiletea
1
1
Asplenietea trichomanis
7
5
Adiantetea
1
?
Thlaspietea rotundifolii
7
6
Lemnetea
3
7
Charetea fragilis
2
?
Potametea
7
13
Montio-Cardaminetea
5
5
Isoeto-Littorelletea
1
?
Phragmito-Magnocaricetea
4
12
Scheucerio-Caricetea nigrae
4
15
Oxycocco-Sphagnetea
1
1
Molinio- Arrhenatheretea
12
10
Festuco-Brometea
11
19
Koelerio-Corynephoretea
3
1
Calluno-Ulicetea
1
1
Trifolio-Geranietea sanguinei
2
?
Helianthemetea guttati
4
2
Thero-Brachypodietea ramosi
?
?
Mulgedio-Aconitetea
4
4
Salicetea herbaceae
1
14
Elyno-Seslerietea
3
3
Carici rupestris-Kobresietea bellardii
1
5
Juncetea trifidi
7
13
Cisto-Micromerietea julianae
?
?
Salicetea purpureae
1
1
Populetea albae
3
2
Alnetea glutinosae
1
?
Nerio-Tamaricetea
1
?
Rhamno-Prunetea
3
2
Querco-Fagetea
7
12
Quercetea pubescentis
4
7
Quercetea roboris
2
?
Loiseleurio-Vaccinietea
4
9
Erico-Pinetea
3
3
Pyrolo-Pinetea
1
?
Vaccinio-Piceetea
4
4
Stellarietea mediae
10
22
Polygono-Poetea annuae
2
?
Artemisietea vulgaris
5
7
Galio-Urticetea
2
1
Epilobietea angustifolii
1
1
Bidentetea tripartitae
1
1
Oryzetea sativae
?
?

Biodiversity & Ecology 4 2012
144
0
1000
2000
3000
until 1960
1991-2000
2006-2010
Fig. 1: Relevé sampling activity. For relevés from literature sources, the year of pub-
lication is used.
Fig. 2: Distribution of data collected over the country.
Up to now, there is no fully developed
and authorized vegetation classification in
Bulgaria according to the Braun-Blanquet
approach. Closest to this goal is the over-
view of Tzonev et al. (2009). The lack of
a complete checklist of syntaxa forced us
to create a provisional one that has been
included in the database. It goes down to
the level of alliances with an indication of
some associations published recently. A
summary is provided in Table 1.
The major part of the relevés is dealing
with herbaceous vegetation. Dry grass-
lands are represented by 2,614 relevés,
halophytic vegetation is recorded by 260
relevés, mesophytic and hygrophytic
grasslands are represented by 1,961
relevés, psammophytic vegetation (along
the Black Sea coast) is recorded by 53
relevés, whereas plant communities that
occur in mountain areas above the tree
line are recorded in 820 relevés.
The distribution of relevés over the
country territory (Fig. 2) indicates a rather
uneven pattern. Quite a number of relevés
represent transitional vegetation types,
which are difficult to apply for classifica-
tion purposes, but in the same time pro-
vide valuable information about vegeta-
tion changes in space and time. The in-
ventory of grasslands (see Fig. 2) covers
about 30% of all herbaceous communities
in the lowlands up to 1,800 m a.s.l.
(Meshinev et al. 2005).
The list of 25 most frequent species in
the database ordered in descending value
include: Plantago lanceolata, Eryngium
campestre, Galium verum, Lotus cornicu-
latus, Achillea millefolium agg., Festuca
valesiaca, Anthoxanthum odoratum,
Teucrium chamaedrys, Agrostis capil-
laris, Trifolium repens, Convolvulus ar-
vensis, Hypericum perforatum, San-
guisorba minor, Cichorium intybus, Dac-
tylis glomerata, Trifolium pratense, Poa
pratensis, Dichanthium ischaemum, Eu-
phorbia cyparissias, Chrysopogon gryl-
lus, Lolium perenne, Cynosurus cristatus,
Potentilla argentea, Agrimonia eupatoria
and Festuca rubra.
The quality of the information in the
Bulgarian Vegetation Database is compa-
rable to that of other national databases
(cf. Chytrý & Rafajová 2003). The most
serious problem seems to be wrong spe-
cies identification and overlooking of
species in the field. Due to outdated taxo-
nomic concepts in the first three volumes
of the Flora of Bulgaria (Jordanov 1963–
1966) and due to the errors in the Field
guide of Bulgarian vascular plants (Koz-
huharov 1992), many colleagues identify
the plants by using additional sources
(e.g. Flora Europaea: Tutin et al. 1968–
1980). In order to avoid biases in further
analyses, there is a need to use aggregates
which include closely related species
and/or subspecies.
Another imperfection of the database is
the lack of data for some of the variables.
For example 9.5% of the records miss
information on altitude, 62.5% on lati-
tude/longitude, 21.1% on total cover and
37.5% on plot size. For the relevés that
lack latitude/longitude data we could add
a UTM grid indication derived from the
description of the locality, but the accu-
racy is rather low because the cells of the
grid are squares with 10 km edge length.
Future perspectives
Although considerable progress on na-
tional level has been gained, there are still
much data waiting to be digitized from
published and unpublished sources. A
rough estimation of published data to be
included in the database amounts to 2,900
relevés. About half of these are related to
forest vegetation, most of the other half to
grasslands. It is rather unclear how many
unpublished records are still not included
in the database. It should be mentioned
that the number of Bulgarian scientists
who do field recording on a regular basis
is not very high and at the moment num-
bers less than 10 persons.
The Bulgarian Vegetation Database is
still the only centralized information
source of its kind on the Balkan Penin-
sula, but we expect that in the near future
neighbouring countries will compile com-
patible databases and thus will provide
opportunities for joint analyses on a re-
gional level.

Biodiversity & Ecology 4 2012
145
C
A
B
Plate: Vegetation types featured by the
vegetation-plot database GIVD EU-BG-
001.
A: Mesic grassland (Molinio-
Arrhenatheretea) with Orchis elegans in
the area of Sofia city. (Photo: I. Apos-
tolova).
B: Dry grassland (Festuco-Brometea)
with Astragalus onobrychis, Anthylis
vulneraria, Scabiosa triniifolia, Artemisia
alba, Stipa eriocaulis in Chepan Mt.,
Western Bulgaria (Photo: K. Vassilev).
C: Wet grassland (Scheuchzerio-
Caricetea fuscae) with Eriophorum
latifolium in Rhodope Mts. (Photo: I.
Apostolova).

Biodiversity & Ecology 4 2012
146
Our database is registered in the Global
Index of Vegetation-Plot Databases
(GIVD; Dengler et al. 2011). In conjunc-
tion with the 9th international Meeting on
Vegetation Databases, which took place
in 2010 at the University of Hamburg, a
South-East European Subgroup of Euro-
pean Dry Grassland Group (SEEDGG
within EDGG; http://www.edgg.org) was
established at a particular workshop. One
of the aims of this subgroup is the con-
struction of a comprehensive database for
dry grasslands in this part of Europe. Due
to status of the Bulgarian Vegetation Da-
tabase, it was decided that this database
should be hosted in our working group.
Acknowlegdements
We are indebted to Dr. Tenyo Meshinev
for his ceaseless inspiration and support,
and to Dr. Jürgen Dengler who stimulated
us to provide this information. The sub-
stantial support and corrections of the
manuscript provided by Joop Schaminée
and one anonymous reviewer are grate-
fully acknowledged.
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Iva Apostolova* (iva@bio.bas.bg),
Desislava Sopotlieva
(desisop@bio.bas.bg), Hristo Pedashenko
(pedashenko@bio.bas.bg), Nikolay Velev
(nvelev@bio.bas.bg) & Kiril Vasilev
(kiril5914@abv.bg)
Department “Flora and Vegetation”,
Institute of Biodiversity and Ecosystem
Research, Bulgarian Academy of Sciences
23 Acad. G. Bonchev Str.
1113 Sofia, BULGARIA
*Corresponding author