The effect of urbanization on plant diversity in two case

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TAIEX Unit
Identification, Protection and Management of
Landscapes based on Natura 2000 (Directive
92/43/EEC)
30 November – 1 December 2004
Sofia
BULGARIA
Dr Georgi Terziyski
Landscape Planning Specialist
Conserving the globally significant biodiversity
in the landscape of Bulgaria’s Rhodope
mountains
GEF Rhodope Project
Development of Landscape Ecology
•
Originated in Central Europe following World War II bridging the gap
between geographers and ecologists
•
Evolved as an interdisciplinary science dealing with the interrelation
between human society and its living space (evolved in West Germany and
Netherlands)
•
Nowadays is recognized as the scientific basis for land and landscape
appraisal, planning, management, conservation, and reclamation
•
Landscape ecology is replacing many of the fields of applied ecology and
geography
•
The most representative body is International Association of Landscape
Ecology (IALE) – Citation of Zonneveld (1982)
Changing Landscape
Heterogeneity of landscape introduced by human activities
Natural habitat
Transformed habitat
TIME
Types of heterogeneity: Spatial (horizontal, vertical); temporal and
functional
Connectivity, corridors and connectedness
Definition of landscape diversity (PEBLDS): the formal expression of the
numerous relations existing in a given period between the individual or a
society and a topographically defined territory, the appearance of which is the
result of the action, over time, of natural and human factors and a combination
of both
Landscape Classifications
Landscape types
Flora and fauna
Development of
vegetation and soil
Natural landscapes
Spontaneous
Not influenced by man
Sub-natural landscapes
Completely or largely
spontaneous
Influenced to some
extent
Semi-natural landscapes
Largely spontaneous
Drastically influenced
(other formation than the
potential natural
Agricultural landscapes
Predominantly
arranged by man
Strongly influenced (soil
often fertilized and
drained, vegetation with
ruderals, neophytes and
garden escapes)
Conceptual Fundaments of Landscape Ecology
Conceptual understanding
•
Central concept is that landscape ecology recognizes the dynamic
role of man in the landscape and the quest for unbiased and
systematic study of its ecological implications
Theories
•
•
•
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The Ecological Hierarchy theory
Percolation theory
The metapopulation
The systems source-sink
Scaling in landscape ecology
•
•
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Spatial and temporal dimensions of scale in landscape ecology
(organism, pattern, process)
Multiscales
Grain size and scaling
The ecological hierarchy and its scientific
disciplines
Human ecology
LANDSCAPE ECOLOGY
ecosystems
Ecosystem ecology
SYN-ECOLOGY
communities
Bio-communities ecology
BIO-ECOLOGY
populations
Population ecology
(dem-ecology)
organisms
Aut-ecology
ECOLOGY OF MAN AND HIS TOTAL ENVIRONMENT
total human ecosystem
Ways of studying the landscape
Landscape approaches are very diverse and it is not possible
to indicate standard methodologies
•
•
•
•
•
•
•
•
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Geostatistics
Geobotany
Animal population analysis
Behavioral ecology
Image processing
GIS
Spatial statistics
Fractal geometry
Computer technologies
Nature conservation and landscape ecology
•Generally conservation policies tend to conserve
structures rather than processes and function
•There are landscape principles for protected areas:
Species richness increases with forest area
A continuous area has more native interior species than two or more
small ones
In a forested area separate patches close to each other support more
species than patches that are further apart
Disjoint patches connected by strips of protected area are preferable
to fully isolated patches
A circular protected area is better than an elongated one because the
portion of interior habitats is larger
To preserve species and processes it is necessary to have enough
space in which natural disturbance can interact with ecosystems
Conclusions
•
Landscape ecology has its roots in Central Europe
•
Landscape is viewed not only as an aesthetic asset, but as the
total spatial and visual entity of human living space (geo, bio, and
noosphere)
•
Currently landscape ecology is viewed in Europe as the scientific
basis for land and landscape planning, management,
conservation, development and reclamation
•
We must be aware when we consider the natural value of the
landscape, as often the cultural landscape has more biological
species then a natural landscape, and in other cases the
degradation results in poor-quality landscape in which species are
reduced
•
Landscape scale is one of the most efficient approaches to
ecosystem management, as the landscape comprises of a large
area where most of the natural and socioeconomic processes
occur, and it can be considered to contain most of the patterns
and processes of interest to us
The most important publications
• Journal of Landscape Ecology
• Conference proceedings from Landscape-Ecological
Impact of Climatic Change (LICC)
• Landscape Heterogeneity and Disturbance (ed Turner 1987)
• Changing Landscapes: An ecological Perspective (ed
Zonneveld & Forman 1990)
• Quantitative Methods in Landscape Ecology (ed Turner &
Gardner 1990)
• Landscape Boundaries (ed Hansen & di Castri 1992)
• Recent publications from Eastern Europe
• Working Group on Red Books for Threatened Landscapes
(IUCN Commission on Environmental Strategy and
Planning and IALE)
• European Landscape Convention - Florence, 20 Oct. 2000
• Publications list (>70 entries) prepared for the presentation
(MS Word file)
Landscape planning for nature
conservation in Bulgaria
• Legislative framework
National and international legislative acts, directives,
conventions, treaties
• Availability of data on biodiversity at local, regional
and national levels
Datasets for biodiversity at municipal, oblast and national level
exists to certain extend
• Issues
Lack of capacity, information, technical capability, methodologies,
inadequate planning policies at local level
• How to bridge the gap between reality and theory?
Technical assistance, capacity building, stricter control on
implementation of legislative acts
School of
Biological
Sciences
THE UNIVERSITY
MANCHESTER
The effect of urbanisation on plant
diversity in two case-study areas –
Bolton, UK and Sofia, Bulgaria
Plant diversity in urban areas: the effect of position,
management level and type of green space
Dr Georgi Terziyski
University of Manchester
School of Biological Sciences
School of Planning and
Landscape
Background
Urbanisation affects plant diversity in two specific ways
 Environmental conditions are altered
 Habitats are fragmented and green space is reduced
Biodiversity value of urban green spaces is thought to
depend on three factors
 Management regime
 Location within the urban matrix
 Connectivity with other vegetated areas
Aims and Objectives
Study aims:

To quantify the ecological effects of urbanisation by assessing the
plant diversity in two comparative urban areas

To test for possible effects of type, position and level of green space
management on plant diversity
Objectives:

To delineate residential and open space land cover categories of urban
morphology in the two case study areas

To carry out a floristic survey in different types of urban green space with
various levels of management within the main residential forms

To assess the role of position and structure of green spaces and their
connectivity for sustaining higher plant diversity in urbanized landscapes
Residential morphology types in Bolton
High density
Medium density
Relative cover of residential types
Low density
Surface cover of residential types
100%
22%
18%
80%
High density
Medium density
24
53
60%
40%
Sealed
76
47
20%
Low density
60%
62
Open
38
0%
high
density
medium
density
low
density
Spatial distribution of residential
morphology types in Bolton
N
BOLTON
GREATER MANCHESTER
DISTRICT BOUNDARY
LOW-DENSITY AREAS
MEDIUM DENSITY AREAS
0
HIGH-DENSITY AREAS
2.5
kilometres
5
Types of green space studied in Bolton
Managed
• Playing fields
• Parks
Recreational park
Football pitch
Unmanaged
• Derelict areas
• Remnants
Dismantled railway
Country park
Species diversity of Bolton green space
Results from a total of 24 sampling plots: 8 for each morphology
type and 6 for each type of green space
Species numbers identified in
four types of green space
Species numbers identified in
three urban morphology types
140
140
120
120
100
100
80
130
60
40
20
0
92
97
107
Parks
80
60
Playing fields
Derelict areas
Remnants
40
112
131
128
High density
Medium density
20
0
Low density
Statistical analysis on vegetation data
Various statistical tests were used to test for
differences in species richness between:
 Green spaces within three urban morphology types
Significant differences were observed (F=4.23, P=0.041)
 Four types of urban green space
Significant differences were observed (F=4.819, P=0.020)
 Green spaces with different levels of management
Significant differences were observed (F=8.066, P=0.011)
 Green spaces with variable size
A positive correlation was observed between size and species number
(R2 =0.56)
 Green spaces connected to or separated from other vegetated areas
No significant differences were observed (F=0.061, P=0.808)
Conclusions

Medium density housing is the most dominant residential type in
Bolton district covering 60% of the housing areas

The type of green space, its management level and position have
a significant effect on the species richness. Well-established
unmanaged derelict and remnant areas have more diverse
vegetation than the regularly managed parks and playing fields

Larger areas of open space support more diverse vegetation

The connectivity between open spaces does not significantly affect
their plant diversity
Residential morphology types in Sofia
High density
Blocks of flats
Low density
Relative cover of each residential type in Sofia
12%
High density
43%
45%
Blocks of flats
Low density
Spatial distribution of residential
morphology types in Sofia
'
Sofia
BULGARIA
BULGARIA
CITY BORDER
LOW-DENSITY AREAS
BLOCKS OF FLATS AREAS
HIGH DENSITY AREAS
0
2.5
kilometres
5
NN
Types of green space studied in Sofia
Managed
• Parks
• Green space along
transport corridors
Recreational park
Roadside vegetation
Unmanaged
• Derelict areas
• Remnants of vegetation
Brownfield area
Rough grassland in
a country park
Species diversity of Sofia green space
Results from a total of 24 sampling plots: 8 for each morphology
type and 6 for each type of green space
Species numbers identified in
four types of green space
Species numbers identified in
three urban morphology types
160
200
140
150
120
100
80
60
40
20
0
110
131
154
155
Parks
100
196
Vegetated road sides
Derelict areas
Remnants
50
0
116
High density
145
Blocks of flats
Low density
Statistical analysis on vegetation data
Various statistical tests have been used to test for
differences in species richness between:
 Green spaces within three urban morphology types
Significant differences were observed (F=27.87, P=0.00)
 Four types of urban green space
Significant differences were observed (F=7.32, P=0.005)
 Green spaces with different levels of management
Significant differences were observed (F=17.08, P=0.001)
Conclusions

Low density (45% ) and blocks of flats (43%) residential
types in Sofia cover nearly equal proportions of the city
housing areas

The type of open space, its position and management
level have a significant effect on the species richness.
Well established unmanaged derelict and remnant
areas have more rich vegetation than regularly
managed green spaces
Final conclusions

The case study areas have different urban morphology and planning practice
 Green spaces within less built up environments shows higher species
richness in both study areas. Those situated in low and medium density
residential types are richer in species
 The type of green space has a significant effect on species diversity. Highly
managed parks and playing field are significantly less rich than unmanaged
derelict and remnant green spaces
 Management has a significant effect on plant diversity
 Connectivity has no significant effect on plant diversity
Acknowledgements
I am grateful for the expert advice and support from:
Dr Bob Callow
(University of Manchester)
Chris Waterfield
(Red Rose Forest Centre)
Dr Dimitar Dimitrov
(Sofia Nature History Museum)
Miss Jane Aspinall
(Bolton City Council)
Dr Roland Ennos
(University of Manchester)
Dr Sarah Lindley
(University of Manchester)
Dr Stephan Pauleit
(University of Manchester)
Financial support for this study is gratefully acknowledged from British
Foreign Commonwealth Office and CEU - Budapest
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