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Abstract

The West African Vegetation Database (http://www.westafricanvegetation.org; GIVD ID AF-00-001) is an online database that has been designed to securely store, edit and manage phytosociological and dendrometrical relevés from West Africa to provide data for research projects dealing with, but not limited to, plant communities, biogeography, population structure, and vegetation dy-namics. An integrated access management system allows data owners to keep data private, to grant selected users access or to make data sets available to the general public. Data entry is possible online or in a local offline database that can be synchronized with the online database. The database allows the calculation of biodiversity indices and has several export options.
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: 105110. DOI: 10.7809/b-e.00065.
105
Long Database Report
The West African Vegetation Database
Marco Schmidt, Thomas Janßen, Stefan Dressler, Karen Hahn, Mipro Hien,
Souleymane Konaté, Anne Mette Lykke, Ali Mahamane, Bienvenu Sambou, Brice
Sinsin, Adjima Thiombiano, Rüdiger Wittig & Georg Zizka
Abstract: The West African Vegetation Database (http://www.westafricanvegetation.org; GIVD ID AF-00-001) is an online database
that has been designed to securely store, edit and manage phytosociological and dendrometrical relevés from West Africa to provide
data for research projects dealing with, but not limited to, plant communities, biogeography, population structure, and vegetation dy-
namics. An integrated access management system allows data owners to keep data private, to grant selected users access or to make
data sets available to the general public. Data entry is possible online or in a local offline database that can be synchronized with the
online database. The database allows the calculation of biodiversity indices and has several export options.
Keywords: data management; dendrometry; dry forest; Guinea Zone; intellectual property right; phytosociology; Sahel Zone; sa-
vanna; Sudan Zone; tree measurements; West Africa.
Received: 17 December 2010 Accepted: 26 May 2011 Co-ordinating Editor: Jens Oldeland.
Introduction
West Africa covers an environmental gra-
dient from the Sahara desert to the rain-
forests of Upper Guinea via steppes and
savannas of the Sahel (Plate A) and Sudan
(Plate B). Mountain chains, inselbergs
and gallery forests (Plate C) interrupt the
zonal patterns of vegetation. It is a region
of rapid environmental change due to a
growing population, over-exploitation,
changing land use practices and climate
change. These changes will have an im-
pact on plant communities and species
and consequently on people’s livelihood
and well-being, all the more in an area
where wild plants are of high economic
and cultural importance. To be able to
conserve plant diversity and ecosystem
goods and services, it is mandatory to
have a good understanding and documen-
tation of it. On the global level, this has
been expressed by the Global Strategy for
Plant Conservation (Secretariat of the
CBD 2002), which explicitly includes the
objective to “develop an integrated, dis-
tributed interactive information system to
manage and make accessible information
on plant diversity”. While more and more
collection data for the region has become
available via GBIF, especially from the
herbaria of Aarhus (AAU), Frankfurt
(FR), Paris (P) and Wageningen (WAG),
the availability of vegetation data was
very much limited up to now and often
restricted to thesis papers that are not
widely distributed. These data are rarely
archived in digital form at the institutional
level and therefore are frequently forgot-
ten or lost when projects end or research-
ers leave science. To overcome this situa-
tion, we decided to develop an online
platform for West African vegetation
data, the West African Vegetation Data-
base, in a collaborative effort of African
and European partners involved in the
BIOTA (http://www.biota-africa.org) and
SUN (http://www.sunproject.dk) projects.
The database is continuously updated and
developed under UNDESERT (http://
www.undesert.neri.dk).
Two workshops on biodiversity data
have been held in November 2007 in
Frankfurt am Main, Germany, and in June
2008 in Ouagadougou, Burkina Faso for
capacity building on general concepts of
biodiversity data, relational databases and
collection management with partners of
all involved institutions. During these
workshops, the needs for an online data-
base on West African vegetation data
have been discussed, and a strategy for
data entry and implementation of the da-
tabase has been developed. These work-
shops have been important not only for
establishing a good cooperation between
the partners, but also resulted in at least
two important structural components of
the database: (1) a data access rights man-
agement scheme to considerably increase
acceptance of the database among local
researchers (for a more thorough treat-
ment of this aspect, see Janßen et al.
2011) and (2) a local offline database tool
including a synchronisation feature with
the online database and designed to cope
with the frequently slow and unreliable
West African internet connections.
Structure
The West African Vegetation Database is
an online database running on a central
Microsoft SQL Server installation. Its
data contents can be synchronized with
and exported to the offline database
VegDa 3.0 running on MS Access 2000.
The data structure builds on the structure
developed for VegDa (Schmidt 2006), a
local vegetation database that originated
in the BIOTA project and had two main
purposes: (1) storing the data of the West
African transect of BIOTA observatories
(for the concept of these observatories,
see Schmiedel & Jürgens 2005, Jürgens et
al. 2012) and other project-related vegeta-
tion data and (2) collecting published data
from the collaborating institutions in or-
Biodiversity & Ecology 4 2012
106
der to get a sound base for biodiversity
studies. Therefore from the start it was
necessary to implement a structure able to
handle different kinds of relevés. A no-
menclatural list of species and infraspeci-
fic taxa including synonymy was taken
from the African Plants Database (Con-
servatoire et Jardin botaniques de la Ville
de Genève & South African National
Biodiversity Institute 2009) and linked to
a hierarchical series of tables for higher
taxonomical units. Another table contains
the relevé events with information about
time, location, plot-related data, investiga-
tor, etc. These two central elements of the
database are linked via two tables for spe-
cies-based relevés (species inventories,
phytosociological relevés according to
different scales) and individuum-based
relevés (dendrometrical relevés), thereby
connecting taxonomic names with relevé
events and including observed values and
eventually voucher specimens. In addition
to this central structure, there are standard
lists of countries and administrative units,
vegetation types (based on the recom-
mendations and conclusions of the Yan-
gambi conference, C.S.A./C.C.T.A.
1956), soil types (based on IUSS Working
Group WRB 2007), structural parameters,
etc. to be used in dropdown lists for error
avoidance and establishment of a com-
mon terminology.
Access rights management is in the re-
sponsibility of data owners and allows
individual relevés to be declared available
to the general public, private (e.g. unpub-
lished data), or shared with selected other
users (e.g. cooperation projects) of the
database. Regardless of access level, all
users may read metadata, except coordi-
nates, of all relevés in the database, so it
is easy to identify potentially interesting
data sets and, in turn, their owners as po-
tential cooperation partners. However,
users may only read detailed data, includ-
ing species lists and cover values for own
and public data sets and for data sets other
users share with them. These may be
searched, added to a data clipboard and
exported for analysis. There are several
export options: (1) into VegDa 3.0, the
local Access database, (2) into crosstables
in comma separated text format that may
be used, e.g., in software for community
analysis and (3) into a Google Earth file
for visualization of the relevé localities.
Biodiversity indices including species
richness, Simpson, Shannon and Pielou’s
evenness (for phytosociological relevés)
and measures such as density, trunk sur-
face area, crown volume and wood vol-
ume (for dendrometrical relevés) are
automatically calculated and can be
downloaded as a comma separated text
file. For index calculation, we followed
Haeupler (1982) in converting Braun-
Blanquet codes into percentage values
using the midpoints of the pure cover
classes and 0.01%, 0.2%, 2.5% for the
classes r, +, 1.
GIVD Database ID: AF-00-001
Last update: 2012-05-09
West African Vegetation Database
Scope: The West African Vegetation Database has been designed to securely store phytosociological and dendrometrical relevés from West
Africa to provide data for analyses of communities, biogeography, population structure, etc. An integrated access management system allows data
owners to give access to selected users or the general public. Data entry is possible online or in a local database version to be synchronized with
the online database.
Status: emerging
Period: 1980-2009
Database manager(s): Marco Schmidt (marco.schmidt@senckenberg.de)
Owner: Senckenberg Research Institute
Web address: http://www.westafricanvegetation.org/
Availability: free online
Online upload: yes
Database format(s): MySQL
Export format(s): MS Access, CSV file
Publication: Schmidt M. 2006. Pflanzenvielfalt in Burkina Faso - Analyse, Modellierung und Dokumentation. Dissertation J.W.Goethe-Universität,
Frankfurt am Main. URL http://publikationen.ub.uni-frankfurt.de/volltexte/2006/3198/ 188 p.
Plot type(s): normal plots
Plot-size range: 25-10000 m²
Non-overlapping plots: 12,000
Estimate of existing plots: 40,000
Completeness: 30%
Total plot observations: 16,074
Number of sources: [NA]
Valid taxa: [NA]
Countries: BF: 50.0%; BJ: 20.0%; NE: 15.0%; SN: 15.0%
Forest: 33% Non-forest: aquatic: 0%; semi-aquatic: 4%; arctic-alpine: 0%; natural: 38%; semi-natural: 17%; anthropogenic: 8%
Guilds: all vascular plants: 70%; only trees and shrubs: 30%; non-terricolous taxa (epiphytic, saxicolous, lignicolous): 3%
Environmental data: [NA]
Performance measure(s): presence/absence only: 10%; cover: 75%; measurements like diameter or height of trees: 15%
Geographic localisation: GPS coordinates (precision 25 m or less): 70%; point coordinates less precise than GPS, up to 1 km: 10%; small grid
(not coarser than 10 km): 15%; political units or only on a coarser scale (>10 km): 5%
Sampling periods: 1980-1989: 10.0%; 1990-1999: 40.0%; 2000-2009: 50.0%
Information as of 2012-07-17; further details and future updates available from http://www.givd.info/ID/AF-00-001
Biodiversity & Ecology 4 2012
107
C
B
A
Plate: Vegetation types featured by
the vegetation-plot database GIVD
AF-00-001.
A: Tiger bush with its alternating
bands of dense woody vegetation
and bare ground is widely distrib-
uted in the Sahel (Photo: M.
Schmidt).
B: A bowal in the Forêt Classée de
Dindéresso near Bobo-Dioulasso.
The shallow soil above lateritic
crusts is often waterlogged during
the rainy season and extremely dry
during the dry season. The typical
vegetation are grass savannas,
woody plants are usually absent
from these habitats (Photo: M.
Schmidt).
C: Gallery forest in the Forêt Clas-
sée du Kou near Bobo-Dioulasso.
Gallery forests of the Sudanian Zone
contain many elements of the more
humid Guinean Zone and are local
hotspots of plant diversity (Photo: M.
Schmidt).
Biodiversity & Ecology 4 2012
108
Contents
The database contains vegetation data
from West Africa that have been digitized
in the course of the SUN and BIOTA pro-
jects, mainly from research within these
projects, the SFB 268 (for an overview of
cooperations between Frankfurt and West
African universities, see Wittig et al.
2009) or from theses at the partner institu-
tions (Guinko 1984, Lykke 1993, 1997,
Kéré 1996, Küppers 1996, Böhm 1998,
Denschlag 1998, Ataholo 2001, Siegl-
stetter 2002, Müller 2003, Krohmer 2004,
Wala 2004, Legba 2005, Tenté 2005, A.
Ouédraogo 2006, Schmidt 2006,
Kirchmair 2008, Mbayngone 2008, Zwarg
2008, O. Ouédraogo 2009).
These studies were often geographi-
cally restricted, some of them had a na-
tional (Guinko 1984) or West African
(Ataholo 2001) coverage. Thematically,
they are diverse with some studies focus-
ing on specific habitats, e.g. segetal (Ata-
holo 2001) or ruderal vegetation (Böhm
1998), bowé (Zwarg 2008), gallery forests
(Lykke & Goudiaby 1999) or termite
mounds (Kirchmair 2008), others on the
local diversity of plant species and com-
munities (e.g. Küppers 1996 in the Gob-
nangou hills and Müller 2003 in the Sahel
of Burkina Faso).
Therefore, data is often geographically
clustered with sampling hotspots sepa-
rated by wide unsampled areas. The same
is true for the habitats. Savannas and dry
forests typical for the respective vegeta-
tion zone are usually well sampled, while
azonal habitats or degraded sites are only
occasionally covered within our database.
A more detailed analysis of sampling pat-
terns in Burkina Faso can be found in
Schmidt et al. (2010b).
The earliest relevés of the database are
from the 1980s, and even though most of
these are not georeferenced to an exact
location, they still have the potential for
reinvestigations to get information on
vegetation change and the impact of land
use and climate change. Very promising
in this context would also be a joint
analysis with data of the FLOTROP data-
base (Daget 2012).
New contributions of relevé data to the
West African Vegetation Database are
therefore highly welcome. Database man-
agers can be contacted via the website
(http://www.westafricanvegetation.org.).
Analysis
Most analyses using our vegetation data-
base focused on species distributions and
geographical patterns of biodiversity. Due
to the heterogeneous sampling patterns,
this usually required the use of species
distribution models. Distributions of the
genus Acacia (Wittig et al. 2004) and the
family Combretaceae (Thiombiano et al.
2006) as well as patterns of vascular plant
diversity (Schmidt et al. 2005) and func-
tional traits in the biogeography of grasses
(Schmidt et al. 2011) have been described
for Burkina Faso at the country scale.
High resolution satellite data as predictors
were used to model diversity patterns for
Burkina Faso’s largest legally protected
area, the “Réserve sylvo-pastorale et par-
tielle de la faune du Sahel” (Schmidt et al.
2008, König et al. 2009). Distribution
changes of woody species due to land use
change have been modeled with high
resolution satellite data for an area in
northern Benin (König et al. 2007).
The previous studies mainly profited
from the high amount of occurrence data,
without using the informations on co-
occurrence and community composition
inherent to vegetation data. Such analyses
have been an integral part of the original
studies, but remain underexploited at the
level of the vegetation database, excep-
tions are a study on the West African BI-
OTA observatories (Schmidt et al. 2010a)
and a comparison of two observatories of
the Fada N’Gourma area with different
land use regimes (Hahn-Hadjali 2006).
Other studies made use of tree meas-
urements: changes in woody vegetation
and species composition have been inves-
tigated in Sahelian Burkina Faso (Lykke
et al. 1999) and fire-disturbed savannas in
Senegal (Lykke et al. 1998, Lykke et al.
2002).
Acknowlegdements
We thank the German Ministry for Educa-
tion and Research (BMBF) for funding
the BIOTA project (funding code:
01LC0617D1), the European Commission
for funding the SUN project (INCO
031685) and UNDESERT project
(243906) and the Hessian Initiative for the
development of scientific and economic
excellence (LOEWE) for funding the
Biodiversity and Climate Research Centre
(BiK-F).
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of the genus Acacia L. in Burkina Faso.
Etudes sur la flore et la végétation du
Burkina Faso et des pays avoisinants 8:
1926.
Wittig, R., Guinko, S., Hahn-Hadjali, K.,
Sinsin, B., Zizka, G., Dressler, S,
Thiombiano, A. (2009): Twenty years of
cooperation between botanists of the
Goethe-University Frankfurt (Germany)
and of West African universities. Flora
et Vegetatio Sudano-Sambesica 12 5
21.
Zwarg, A. (2008): Flora und Vegetation auf
Lateritkrusten im Südosten Burkina
Fasos. Diplom thesis, J.W. Goethe
University Frankfurt am Main.
Biodiversity & Ecology 4 2012
110
Marco Schmidt*
(marco.schmidt@senckenberg.de),
Thomas Janßen
(thomas.janssen@biologie.hu-berlin.de),
Stefan Dressler
(stefan.dressler@senckenberg.de) &
Georg Zizka
(georg.zizka@senckenberg.de )
Department of Botany and Molecular
Evolution, Senckenberg Research
Institute
Senckenberganlage 25
60325 Frankfurt, GERMANY
Karen Hahn (karen.hahn@bio.uni-
frankfurt.de), Marco Schmidt, Rüdiger
Wittig ( r.wittig@bio.uni-frankfurt.de) &
Georg Zizka
Biodiversity and Climate Research Centre
(BiK-F)
Senckenberganlage 25
60325 Frankfurt, GERMANY
Marco Schmidt, Stefan Dressler, Karen
Hahn, Rüdiger Wittig & Georg Zizka
Institute for Ecology, Evolution and
Diversity,
Goethe University,
Siesmayerstr. 70
60323 Frankfurt, GERMANY
Thomas Janßen
Dept. of Botany and Arboretum
Humboldt University
Unter den Linden 6
10099 Berlin, GERMANY
Mipro Hien (miphien@gmail.com )
Department of Water and Forest,
Polytechnical University of Bobo-
Dioulasso
01 BP 1091
Bobo-Dioulasso 01, BURKINA FASO
Souleymane Konaté
(souleymane.konate@iucn.org ) ,
Université de Abobo-Adjamé
BP 28 N’Douci
Abidjan, IVORY COAST
Anne Mette Lykke (aml@dmu.dk )
Dept. of Terrestrial Ecology, NERI
National Environmental Research
Institute, Aarhus University
Vejlsøvej 25
8600 Silkeborg, DENMARK
Ali Mahamane (ali_mahamane@yahoo.fr)
Laboratory Garba Mounkaila of Biology,
Faculty of Sciences, University Abdou
Moumouni of Niamey
BP 10662
Niamey, NIGER
Bienvenu Sambou (ise_dir@orange.sn )
Institute of Environmental Sciences,
Faculty of Sciences and Technology,
University Cheikh Anta Diop of Dakar
BP 5005
Dakar, SENEGAL
Brice Sinsin (bsinsin@gmail.com )
Laboratory of Applied Ecology,
University of Abomey-Calavi
03 BP 1974
Cotonou, BENIN
Adjima Thiombiano
(adjima_thiombiano@yahoo.fr )
Laboratory of Plant Biology and Ecology,
UFR Life and Earth Sciences, University
of Ouagadougou
03 BP 848
Ouagadougou 03, BURKINA FASO
*Corresponding author
... The wide assessment of occurrence data enables us to catch the niche more completely, covering conditions that may in future climates occur in the area of interest. Data were obtained from the Ouagadougou University Herbarium (VegDa_OUA) (Schmidt et al., 2005) which includes data from various Ph.D and Master's theses (see Table 1), the SIG IVOIRE database (Chatelain et al., 2001), Flotrop (Daget, 2012), SeSam (the collection database of the Herbarium Senckenbergianum; Schmidt et al., 2006), the African Plants Photo Guide (Dressler et al., 2014), the West African Vegetation Database (Schmidt et al., 2012), CIRAD France (Hall et al., 1996), the Global Biodiversity Information Facility (GBIF; www.gbif. org/) and personal field data of the year 2014 (Table 1). ...
... The 10th percentile training logistic threshold value for discriminating suitability level was 0.3207. (Schmidt et al., 2005) 672 Field Burkina Faso SIG IVOIRE (Chatelain et al., 2001) 21 Field Cote d'Ivoire Flotrop (Daget, 2012) 325 Field Benin Flotrop (Daget, 2012) 46 Field Togo Flotrop (Daget, 2012) 85 Field Nigeria Flotrop (Daget, 2012) 01 Field Senegal Flotrop (Daget, 2012) 46 Field Niger Flotrop (Daget, 2012) 140 Field Mali Flotrop (Daget, 2012) 06 Field Guinea Flotrop (Daget, 2012) 54 Field Cote d'Ivoire SeSam (Schmidt et al., 2006) 06 Herbarium Burkina Faso SeSam (Schmidt et al., 2006) 01 Herbarium Benin AfricanPlants (Dressler et al., 2014) 24 Herbarium Mali AfricanPlants (Dressler et al., 2014) 34 Herbarium Burkina Faso AfricanPlants (Dressler et al., 2014) 01 Herbarium Cote d'Ivoire AfricanPlants (Dressler et al., 2014) 04 Herbarium Benin West African Vegetation (Schmidt et al., 2012) 35 Field Burkina Faso West African Vegetation (Schmidt et al., 2012) 03 Field Togo West African Vegetation (Schmidt et al., 2012) 35 Field Benin CIRAD France (Hall et al., 1996) 16 Herbarium Burkina Faso CIRAD France (Hall et al., 1996) 57 Herbarium Nigeria CIRAD France (Hall et al., 1996) 23 Herbarium Benin CIRAD France (Hall et al., 1996) 07 Herbarium Niger CIRAD France (Hall et al., 1996) 18 Herbarium Mali CIRAD France (Hall et al., 1996) 03 Herbarium Togo CIRAD France (Hall et al., 1996) 18 Herbarium Ghana CIRAD France (Hall et al., 1996) 11 Herbarium Cote d'Ivoire CIRAD France (Hall et al., 1996) 6 Herbarium Guinea CIRAD France (Hall et al., 1996) 04 Herbarium Guinea Bissau CIRAD France (Hall et al., 1996) 12 Herbarium Senegal The predicted suitable habitats of V. paradoxa are shown for the two models in Fig. 6. In general, the results show that the habitats that are currently suitable for the conservation of V. paradoxa are mainly located in the Sudanian climatic zone (9°20′-12°20′N) to the South of Burkina Faso. ...
... The 10th percentile training logistic threshold value for discriminating suitability level was 0.3207. (Schmidt et al., 2005) 672 Field Burkina Faso SIG IVOIRE (Chatelain et al., 2001) 21 Field Cote d'Ivoire Flotrop (Daget, 2012) 325 Field Benin Flotrop (Daget, 2012) 46 Field Togo Flotrop (Daget, 2012) 85 Field Nigeria Flotrop (Daget, 2012) 01 Field Senegal Flotrop (Daget, 2012) 46 Field Niger Flotrop (Daget, 2012) 140 Field Mali Flotrop (Daget, 2012) 06 Field Guinea Flotrop (Daget, 2012) 54 Field Cote d'Ivoire SeSam (Schmidt et al., 2006) 06 Herbarium Burkina Faso SeSam (Schmidt et al., 2006) 01 Herbarium Benin AfricanPlants (Dressler et al., 2014) 24 Herbarium Mali AfricanPlants (Dressler et al., 2014) 34 Herbarium Burkina Faso AfricanPlants (Dressler et al., 2014) 01 Herbarium Cote d'Ivoire AfricanPlants (Dressler et al., 2014) 04 Herbarium Benin West African Vegetation (Schmidt et al., 2012) 35 Field Burkina Faso West African Vegetation (Schmidt et al., 2012) 03 Field Togo West African Vegetation (Schmidt et al., 2012) 35 Field Benin CIRAD France (Hall et al., 1996) 16 Herbarium Burkina Faso CIRAD France (Hall et al., 1996) 57 Herbarium Nigeria CIRAD France (Hall et al., 1996) 23 Herbarium Benin CIRAD France (Hall et al., 1996) 07 Herbarium Niger CIRAD France (Hall et al., 1996) 18 Herbarium Mali CIRAD France (Hall et al., 1996) 03 Herbarium Togo CIRAD France (Hall et al., 1996) 18 Herbarium Ghana CIRAD France (Hall et al., 1996) 11 Herbarium Cote d'Ivoire CIRAD France (Hall et al., 1996) 6 Herbarium Guinea CIRAD France (Hall et al., 1996) 04 Herbarium Guinea Bissau CIRAD France (Hall et al., 1996) 12 Herbarium Senegal The predicted suitable habitats of V. paradoxa are shown for the two models in Fig. 6. In general, the results show that the habitats that are currently suitable for the conservation of V. paradoxa are mainly located in the Sudanian climatic zone (9°20′-12°20′N) to the South of Burkina Faso. ...
Article
Vitellaria paradoxa, the shea tree, an economically important fruit-tree species native to savanna regions is threatened in Burkina Faso due to overexploitation and changing land-use. Furthermore, it remains unclear how climate change will influence its frequency and distribution. We investigated the impact of climate change on the projected spatial distribution of favorable habitats for V. paradoxa. Species distribution modeling techniques implemented in MaxEnt combined with GIS were used to forecast the current and future distribution of V. paradoxa. We selected two climatic scenarios (RCP4.5 and RCP8.5) and two global climate models (MPI-ESM-MR and HadGEM2-ES) to encompass the full range of variation in the models. Presence records of the species were collected and linked to bioclimatic and edaphic variables. The most characteristic and least correlated variables were selected for modeling after a collinearity test. Under current climatic conditions, ~51% of the national area was found to be favorable for cultivation and conservation of the species. Under future climate projections, our models predict that favorable habitats of this species will decline by 12% (RCP4.5) and 13% (RCP8.5) by 2070. The predictive modeling approach presented here may be applied to other economically important tree species.
... To a lesser extent, such data are also available for plants (e.g. Sosef et al. 2017;Schmidt et al. 2012). For fungi and fungus-like organisms (other organisms traditionally studied by mycologists) in West Africa, however, documentation of species diversity started later and was slow because there were only few mycologists. ...
... Nevertheless, there are published accounts (floras) of the plants of most West African countries including keys and species descriptions, as well as plant checklists and databases (e.g. Daget 2012;Schmidt et al. 2012) available for phytogeographic analyses (e.g. Klopper et al. 2007). ...
Article
Full-text available
Abstract Scientific information about biodiversity distribution is indispensable for nature conservation and sustainable management of natural resources. For several groups of animals and plants, such data are available, but for fungi, especially in tropical regions like West Africa, they are mostly missing. Here, information for West African countries about species diversity of fungi and fungus-like organisms (other organisms traditionally studied by mycologists) is compiled from literature and analysed in its historical context for the first time. More than 16,000 records of fungi representing 4843 species and infraspecific taxa were found in 860 publications relating to West Africa. Records from the Global Biodiversity Information Facility (GBIF) database (2395 species), and that of the former International Mycological Institute fungal reference collection (IMI) (2526 species) were also considered. The compilation based on literature is more comprehensive than the GBIF and IMI data, although they include 914 and 679 species names, respectively, which are not present in the checklist based on literature. According to data available in literature, knowledge on fungal richness ranges from 19 species (Guinea Bissau) to 1595 (Sierra Leone). In estimating existing species diversity, richness estimators and the Hawksworth 6:1 fungus to plant species ratio were used. Based on the Hawksworth ratio, known fungal diversity in West Africa represents 11.4% of the expected diversity. For six West African countries, however, known fungal species diversity is less than 2%. Incomplete knowledge of fungal diversity is also evident by species accumulation curves not reaching saturation, by 45.3% of the fungal species in the checklist being cited only once for West Africa, and by 66.5% of the fungal species in the checklist reported only for a single country. The documentation of different systematic groups of fungi is very heterogeneous because historically investigations have been sporadic. Recent opportunistic sampling activities in Benin showed that it is not difficult to find specimens representing new country records. Investigation of fungi in West Africa started just over two centuries ago and it is still in an early pioneer phase. To promote proper exploration, the present checklist is provided as a tool to facilitate fungal identification in this region and to aid conceptualisation and justification of future research projects. Documentation of fungal diversity is urgently needed because natural habitats are being lost on a large scale through altered land use and climate change.
... In the vast majority of biodiversity databases, "habitat-type" (a pragmatic variant of the holistic concept of ecosystem-type; Senterre and Wagner, 2014) is perceived as an attribute of observations made on species (Dauby et al., 2016: RAINBIO;Filer, 2010: BRAHMS;(Missouri Botanical Garden 2021): TROPICOS; Yesson et al., 2007: GBIF) and consequently it is provided simply as a comment. By contrast, in phytosociology and for vegetation specialists, habitat-type is an attribute of a vegetation plot, which is primarily an inventory of species (Gillet, 2011: Phytobase;Gillison, 2002: VegClass;Hennekens and Schaminée, 2001: TURBOVEG;Peacock et al., 2007: RAINFOR;Peet et al., 2012: VegBank;Schmidt et al., 2012). Habitat is then often described using certain environmental characters, but neither in detail nor using a framework that integrates scales of space and time, such as the one we propose here. ...
Article
Full-text available
Over the last several years, the IUCN Red List approach for assessing the risk of extinction faced by species has been adapted into a Red List of Ecosystems methodology. This endeavor faces several important challenges, including how to define the types of ecosystems to which the Red List criteria are applied, and how to manage information on the geographic distribution of ecosystems in an open, transparent, and standardized manner linking mapping, typology, and field studies. We propose a fundamentally novel approach that differs from currently available ecosystem typologies in three important aspects by (1) offering a new way of conceptualizing types of ecosystems, (2) providing an explicit method for communicating the conceptualized ecosystems and how they are circumscribed, and (3) developing technical tools for managing the resulting conceptual model. Firstly, ecosystem types are defined by studying biogeoclimatic gradients using an approach that is both modular (in which combinations of ecological factors are studied at a given scale) and hierarchical (involving relative spatial and temporal scales in which local/site gradients are dependent on bioclimatic/regional gradients). This avoids the problem of classes that are not mutually exclusive and enables the classification of all types of ecosystems, including for example marshes on rocky outcrops in superhumid tropical montane areas. Secondly, the names of ecosystem species are linked to a nomenclatural type defined by a ‘type site’ or ‘biotype’, adopting a principle that makes clear a given author's notion of an ecosystem type even if the accompanying name and description are partial or imperfect, or when the ecosystem type is delimited too broadly according to the interpretation of another author. Ecosystem names are structured as a descriptive diagnosis based on a standardized set of characters and character states. This typological approach for facilitating the naming and comparison of ecosystem circumscriptions is thus truly taxonomic in nature. Thirdly, in order to facilitate the use and application of the conceptual approach presented here, we translate it into a practical tool by developing a smartphone-based system to collect data for observing and describing virtual ecosystem specimens in the field, along with the "Bio" database, which manages ecosystem data and also enables tracking synonymies using an open system that entails assigning determinavits to biotypes.
... Approximately 78% (116,000) of the records are derived from vegetation surveys and the remaining 22% (32,000) are derived from herbarium specimens. Major data contributors were the Flotrop database (32,000 records; Daget 2012), the herbarium collections of WAG (19,000), OUA (5,900), FR (5,600) and AAU (1,600), SIG-Ivoire (8600; Chatelain et al. 2011), African plants-a photo guide (1500; Dressler et al. 2014) and vegetation survey data from multiple studies obtained from the West African Vegetation database (75,000; Schmidt et al. 2012). The median number of occurrences was 29 per species (mean = 93) and the maximum number of records for one species was 2,224 for Combretum glutinosum Perr. ...
Article
Full-text available
West Africa is a floristically understudied region that is facing severe environmental changes in the 21st century. Basic distribution data and information on the conservation status for most plant species of the region are scarce, and good information only exists for small areas of interest or for key species. This lack of knowledge seriously hampers urgently needed regional conservation efforts. Here we present comprehensive distribution information and preliminary, automated species conservation assessments for the flora of Burkina Faso, a country in tropical West Africa with a flora and vegetation typical for the savanna belt of the region. We documented and analysed the distribution of 1,568 species or 80% of the flora of Burkina Faso based on an expert curated dataset comprising ca. 150,000 occurrence records from herbarium specimens and vegetation surveys. We used this dataset and environmental niche models to calculate three indicator variables for a preliminary, automated conservation assessment. We classified 350 species (18% of the flora, excluding introduced species) as potentially "Critically Endangered", "Endangered", "Vulnerable" or "Near-Threatened" on the national level. The analyses confirmed species-rich areas in the south-west and south-east of the country, and showed a particular concentration of potentially Endangered species in the south. Furthermore, the proportion of potentially Endangered species differed between plant families, growth forms and habitats. Our results set the base for further plant geographical and ecological studies and are a data-driven baseline for further conservation assessments and large scale conservation strategies of the West African flora.
... Tree distribution data were compiled from a Burkina Faso tree species distribution map prepared by Terrible [32](S1 Dataset); collection data from the Herbarium Senckenbergianum (FR) and the Aarhus University (AAU) herbarium from the West African Vegetation Database [33] (S1 Dataset); georeferenced photo records of African Plants [34] (S1 Dataset); observation records from a transect study of useful tree species in western Burkina Faso [35] (S1 Dataset); and point locations obtained from the Global Biodiversity Information Facility [36], available within the range of 18 degrees west to 16 degrees east in longitude and latitudes of 4 to 28 degrees north. ...
Article
Full-text available
Over the last decades agroforestry parklands in Burkina Faso have come under increasing demographic as well as climatic pressures, which are threatening indigenous tree species that contribute substantially to income generation and nutrition in rural households. Analyzing the threats as well as the species vulnerability to them is fundamental for priority setting in conservation planning. Guided by literature and local experts we selected 16 important food tree species (
... Although large collections of vegetation-plot data are now available from national to continental levels (e.g., Enquist, Condit, Peet, Schildhauer, & Thiers, 2016;Peet, Lee, Jennings, & Faber-Langendoen, 2012;Schaminée, Hennekens, Chytrý, & Rodwell, 2009;Schmidt et al., 2012), they are rarely used in global-scale biodiversity research (Franklin, Serra-Diaz, Syphard, & Regan, 2017;Wiser, 2016). This is unfortunate because vegetationplot data may reveal important patterns that cannot be captured by grid-based datasets (Table 1). ...
... Although large collections of vegetation-plot data are now available from national to continental levels (e.g., Enquist, Condit, Peet, Schildhauer, & Thiers, 2016;Peet, Lee, Jennings, & Faber-Langendoen, 2012;Schaminée, Hennekens, Chytrý, & Rodwell, 2009;Schmidt et al., 2012), they are rarely used in global-scale biodiversity research (Franklin, Serra-Diaz, Syphard, & Regan, 2017;Wiser, 2016). This is unfortunate because vegetationplot data may reveal important patterns that cannot be captured by grid-based datasets (Table 1). ...
Article
Full-text available
Questions: Vegetation-plot records provide information on presence and cover or abundance of plants co-occurring in the same community. Vegetation-plot data are spread across research groups, environmental agencies and biodiversity research centers, and thus, are rarely accessible at continental or global scales. Here we present the sPlot database, which collates vegetation plots worldwide to allow for the exploration of global patterns in taxonomic, functional and phylogenetic diversity at the plant community level. - Location: sPlot version 2.1 contains records from 1,121,244 vegetation plots, which comprise 23,586,216 records of plant species and their relative cover or abundance in plots collected between 1885 and 2015. - Methods: We complemented the information for each plot by retrieving environmental conditions (i.e. climate and soil) and the biogeographic context (i.e. biomes) from external sources, and by calculating community-weighted means and variances of traits using gap-filled data from the global plant trait database TRY. Moreover, we created a phylogenetic tree for 50,167 out of the 54,519 species identified in the plots. - Results: We present the first maps of global patterns of community richness and community-weighted means of key traits. - Conclusions: The availability of vegetation plot data in sPlot offers new avenues for vegetation analysis at the global scale.
Article
Full-text available
Assessing biodiversity status and trends in plant communities is critical for understanding, quantifying and predicting the effects of global change on ecosystems. Vegetation plots record the occurrence or abundance of all plant species co‐occurring within delimited local areas. This allows species absences to be inferred, information seldom provided by existing global plant datasets. Although many vegetation plots have been recorded, most are not available to the global research community. A recent initiative, called ‘sPlot’, compiled the first global vegetation plot database, and continues to grow and curate it. The sPlot database, however, is extremely unbalanced spatially and environmentally, and is not open‐access. Here, we address both these issues by (a) resampling the vegetation plots using several environmental variables as sampling strata and (b) securing permission from data holders of 105 local‐to‐regional datasets to openly release data. We thus present sPlotOpen, the largest open‐access dataset of vegetation plots ever released. sPlotOpen can be used to explore global diversity at the plant community level, as ground truth data in remote sensing applications, or as a baseline for biodiversity monitoring. Vegetation plots (n = 95,104) recording cover or abundance of naturally co‐occurring vascular plant species within delimited areas. sPlotOpen contains three partially overlapping resampled datasets (c. 50,000 plots each), to be used as replicates in global analyses. Besides geographical location, date, plot size, biome, elevation, slope, aspect, vegetation type, naturalness, coverage of various vegetation layers, and source dataset, plot‐level data also include community‐weighted means and variances of 18 plant functional traits from the TRY Plant Trait Database. Global, 0.01–40,000 m². 1888–2015, recording dates. 42,677 vascular plant taxa, plot‐level records. Three main matrices (.csv), relationally linked.
Preprint
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Global change impacts on the Earth System are typically evaluated using biome classifications based on trees and forests. However, during the Cenozoic, many terrestrial biomes were transformed through the displacement of trees and shrubs by grasses. While grasses comprise 3% of vascular plant species, they are responsible for more than 25% of terrestrial photosynthesis. Critically, grass dominance alters ecosystem dynamics and function by introducing new ecological processes, especially surface fires and grazing. However, the large grassy component of many global biomes is often neglected in their descriptions, thereby ignoring these important ecosystem processes. Furthermore, the functional diversity of grasses in vegetation models is usually reduced to C 3 and C 4 photosynthetic plant functional types, omitting other relevant traits. Here, we compile available data to determine the global distribution of grassy vegetation and key traits related to grass dominance. Grassy biomes (where > 50% of the ground layer is covered by grasses) occupy almost every part of Earth’s vegetated climate space, characterising over 40% of the land surface. Major evolutionary lineages of grasses have specialised in different environments, but species from only three grass lineages occupy 88% of the land area of grassy vegetation, segregating along gradients of temperature, rainfall and fire. The environment occupied by each lineage is associated with unique plant trait combinations, including C 3 and C 4 photosynthesis, maximum plant height, and adaptations to fire and aridity. There is no single global climatic limit where C 4 grasses replace C 3 grasses. Instead this ecological transition varies biogeographically, with continental disjunctions arising through contrasting evolutionary histories. Significance statement Worldviews of vegetation generally focus on trees and forests but grasses characterize the ground layer over 40% of the Earth’s vegetated land surface. This omission is important because grasses transform surface-atmosphere exchanges, biodiversity and disturbance regimes. We looked beneath the trees to produce the first global map of grass-dominated biomes. Grassy biomes occur in virtually every climate on Earth. However, three lineages of grasses are much more successful than others, characterizing 88% of the land area of grassy biomes. Each of these grass lineages evolved ecological specializations related to aridity, freezing and fire. Recognizing the extent and causes of grass dominance beneath trees is important because grassy vegetation plays vital roles in the dynamics of our biosphere and human wellbeing.
Poster
Full-text available
In the last decades significant vegetation changes in West African savannas due to changing climatic conditions and increasing human impact became obvious. Whereas the dynamics of vegetation cover were intensively observed, the knowledge about changing species compositions and phytodiversity dynamics remains scarce. For a better understanding of current processes permanent plots were installed in protected and pastured areas in the Sudanian Zone of Burkina Faso. The investigations are part of a continent wide monitoring of the BMBF-funded BIOTA Africa project (www.biota-africa.de). The results of the first year inventory in pastured and protected plots show, that therophytes and chamaephytes increase significantly under pasture pressure and lead to a higher phytodiversity but at the same time to a qualitative degradation: widely distributed ruderal and segetal annual species increase whereas perennial grasses with partly good fodder qualities decrease. Species richness of the woody layer is so far not affected. The evaluation of the woody population dynamics indicates a disturbed regeneration for several species, which at long term is supposed to lead to their severe decline.
Book
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The complete text of all contributions of the book is freely available from: http://www.biodiversity-plants.de/biodivers_ecol/vol4.php
Article
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The year 1989 represents the starting point of the cooperation between botanists of the Goethe-University in Frankfurt (Germany) and of the University of Ouagadougou (Burkina Faso). Some years later, the University of Abomey-Calavi (Benin) joined the cooperation. This paper gives an overview on joint projects, resulting publications and theses, and on other achievements of this fruitful cooperation, which meanwhile also comprises partners of Ivory Coast, Niger and Senegal.
Thesis
This study was part of the BIOTA research program on phytodiversity evaluation and evolution of West African Sahelian and Sudanian vegetation. It aimed to assess floristic diversity, the potential for woody vegetation regeneration, and the dynamics of nine declining high-value plant species. Research was carried out across a climatic gradient from North to South, covering the four phytogeographical zones of Burkina Faso. The vegetation was surveyed using phytosociological methods. In addition, a quantitative inventory of the juvenile population (D1.30 < 5 cm) was conducted by counting both individuals and their heights. The population dynamics of nine useful woody plant species were evaluated by assessing their population structure and regeneration characteristics. The results showed a species richness of 204 woody plant species, across 49 families and 129 genera. This represented nearly 20% of the published vascular plants of Burkina Faso. Across the phytogeographical zones, the flora was characterised by a few common species. The dominant families did not vary significantly between climatic zones and Combretaceae, Mimosaceae, Caesalpiniaceae and Rubiaceae were most common. Species richness and floristic diversity were highest in the Sudanian vegetation zone. However, the Sahel flora contributed to increase overall diversity by adding some specific species. Some vegetation types or ecological niches harboured a unique flora or high phytodiversity. The juvenile flora exhibited well-balanced dynamics through the global population structure, but very few species had good regeneration dynamics. Overall, Combretum glutinosum and Combretum nigricans showed the best regeneration dynamics. Several species displayed high regeneration potential, but their contribution to overall population regeneration was low. There is a significant risk of phytodiversity decline as some families were represented by only one species. The nine species of high-value showed a general regression dynamic characterised by mature populations and a lack of regeneration. Weak regeneration and a high rate of physical damage in Afzelia africana and Dalbergia melanoxylon stands were evidence of natural regression. In populations of Anogeissus leiocarpus, Bombax costatum, Boswellia dalzielii, Burkea africana, Pterocarpus erinaceus, Pterocarpus lucens and Sterculia setigera, the most important regression factor was strong human pressure. However, some of these species showed impressive natural regeneration potential. Germination tests indicated a respectable capacity for sexual reproduction in seven species that had shown poor natural regeneration. Silviculture of Dalbergia melanoxylon and Sterculia setigera could have lesser cost and reduce pressure on natural populations as both species had a rapid growth rate and a positive response to transplantation.