the vegetation of the park lawns in munich a diploma thesis in biology about vegetation ecology and...
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The vegetation of the park lawns in Munich
A diploma thesis in biology
about vegetation ecology and city ecology
Table of contents 1 Introduction
2 Means and techniques
3 Results
4 Discussion
5 Summary
Def.: Park lawns are grasslands in
• Gardens• Parks • Sports grounds
that become regular cut and stepped on.
They are mowed according to their height and the weather up to 35 times per year.
1 Introduction
Interrelation of the site factors1 Introduction
sun temperature ground water nitrogen
species number
earthworms pointer values age cutting
light climate water soil
PLANT
fauna competition time use
2 Means and techniques
2 Means and techniques
10°
A. Abiotical factors 16 physical variables
B. Biotical factors 49 site factors (vegetation)
C. Use factors 6 care factors (mowing)
Air temperature [°C] Relative air humidity [%]
10°
9°8°7°6°5°
80%85%90%95%
A. Abiotical factors2 Means and techniques
List of biotic influence factors – won by maps or aerial photograph
• Position geographical coordinates, GPS east/north [m]
• Groundwater state middle [m], variation [m], distance [m]
• Exposition sun-exposed face [m²], entire face [m²]
• Sea level distance to the middle sea level [m]
• Climate air temperature [°C], relative air humidity [%]
• Soil types arranged according to usable humidity
B. Biotical factors2 Means and techniques
List of biotic factors – won by fieldwork
• Temperature-nu. optimal 15 °C at day and 10 °C at night
• Neophytes foreign plants or grade of human influence
• Legumes (Fabales) distinguish burdened and extensive sites
• Light-number forest plants have a small light compatibility
• Nitrogen-number nutrient supply or degree of fertilization
• Salt-number osmotic budget or transpiration coefficient
• Growth form therophytes (1-2a), geophytes (earth plants)
• Species number number of different plant species per site
C. Use factors2 Means and techniques
The use on some sites is since over 300 years the same (Hofgarten).
Step load through bumpkin paths in the English Garden
1795
1613
today
today
C. Use factors2 Means and techniques
List of the six use factors – raised by research
• Age time [a] and influence of natural succession• R-strategists are replaced by C-strategists
• Sum of the cuts adaptation to the cutting over time
• Cut technique sickle mower, spindle mower, girder mower and sheep
• Degree of human describes the intensity of influence use and disturbance
• Cut frequency cuts per year [aˉ¹ ], mowing is the strongest disturbance to the vegetation
• Step load stress-tolerant S-strategists (Poa annua)
3 Results
3 Results
Artenzahl
403530252015105
Artenzahl
Häu
figk
eit
60
50
40
30
20
10
0
Std.abw. = 7,96
Mittel = 14
N = 195,00
Species number (x) and frequency (y)
A. Descriptive statistic
Species number
Fre
qu
en
cy
raw data (frequency)
B. Analytical statisticmathematical processing (correlation, regression)
The frequency of the factor species number. Easy to recognize is the normal distribution curve. The average species number is 14.The standard deviation is 7.96Park lawns have a small species number.
B. Analytical statistic3 Results
Correlation (PEARSON) – math. relationship when coefficient > 0,5
Disturbance indicators Flower meadowsTemperature,
groundwater state (distance)
Relative air humidity,
soil type (usable humidity)
Therophytes (1-2a),
Light-number, Temperature-
number, Nitrogen-number,
Salt-number
Fabales, herbs, grasses,
species number, diversity,
number of neophytes,
geophytes, hemikryptophytes
Age, cut frequency,
sum of cuts, step load,
degree of human influence
Cut technique
(e.g. sheep)
0
10
20
30
40
50
1 2 3 4 5 6 7
Fabales
Art
enza
hl
B. Analytical statistic3 Results
Regression curve of a biotical factor - number of different sorts of Fabales (x) with species number (y)
Number of different sorts of Fabales
Sp
ecie
s n
um
ber
The species number is strongly positively correlated with the number of legumes
0
10
20
30
40
50
4,0 4,5 5,0 5,5 6,0 6,5 7,0 7,5
Nitrogen-numberS
pe
cie
s n
um
be
r
B. Analytical statistic
0
10
20
30
40
50
6,5 7,0 7,5 8,0
Light-number
Spe
cies
num
ber
3 Results
Regression curves of the pointer values Light-number and Nitrogen-number (x) with species number (y)
Sp
ecie
s n
um
ber
Nitrogen-number
Sp
ecie
s n
um
ber
Light-number
The Nitrogen-number correlates negatively with the species number.
The regression curve shows that the species number has an optimum (17.9 species) with the Light-number of 6.89.
B. Analytical statistic
3 Results
Regression curve of a use factor – number of cuts per year (x) with species number (y)
0
10
20
30
40
50
0 10 20 30
Cut frequency [1/a]
Kin
d nu
mbe
r
Number of cuts per year
Sp
ecie
s n
um
ber
In adornment lawns the species number is higher than in most park lawns.
B. Analytical statistic3 Results
Cluster analysis – section of a hierarchical dendrogram (similarity tree) of the species, the upper ones resemble more
Strong light plants (Achillea millefolium), very small growing (Poa trivialis), meagreness hands (Holcus lanatus)
Step plants (Plantago media), dryness-resistant grasses (Elymus repens), extreme cut compatibility (Agrostis stolonifera)
Rosette plants (Bellis perennis), average-high meadow plants (Veronica filiformis), humidity indicators (Ranunculus repens)
B. Analytical statistic3 Results
Canonical correspondence analysis – ordination of use factors
step load
species numberage
cut frequency
sum of cuts
cut technique
0
0
0
0
0
0
0
-1 -1 0 0 0 0 0 0 0 0 0 1 1
66
degree of human
influence
Flower meadowsDisturbance indicators
B. Analytical statistic3 Results
Fabales
herbs
grasses
step load
species numberage
cut frequency
sum of cuts
cut technique
Light-number
Temp.-number
Nitrogen-number
Salt-number
therophytes
geophytes
H. rosulata(Bellis perennis )
number of neophytes
0
0
0
0
0
0
0
-1 -1 0 0 0 0 0 0 0 0 0 1 1
6
6
CCA – ordination of use factors and biotical factors
degree of human
influence
Flower meadowsDisturbance indicators
years
4. Discussion4 Discussion
Progressive (natural) and regressive (anthropogen) succession
temporary stage
shrubs, shrubbery
pioneer stage
grasses, herbs
final stage
forest
Progressive succession
Regressive succession
raw earth
fallow
spindle mower girder mower chainsaw
4. Discussion4 Discussion
Transformation of park lawns into species-rich flower meadows
Mowing once or twice annually
Girder mower or spindle mower
Cut height more than 7 cm
Sage smooth oat meadow (Arrhenatherion elatioris)
Insects and macrofauna can survive (lizards)
Nutrients in the upper ground must be reduced through impoverishment
The plants must develop fully before they are mowed
Best by the means of the hay flower sowing with autochthonous seed
Semination on raw earth or overseeding
Sickle mower shreds the blade of grass
Nitrogen entry through the air is 50 kg haˉ¹ aˉ¹
(= 5 g mˉ² aˉ¹)
5. Summary5 Summary
Synecological investigation of the Munich park lawns
The vegetation of the Munich park lawns is very similar; the faces are often mowed, which results in a small species variety. The nutrient number, the growth form geophytes and the disturbance through the human being are the strongest site factors of the entire investigation.
The most important abiotical factors are the relative air humidity, the groundwater state and the air temperature.
The effective biotical factors are stress indicators like Nitrogen-number, Salt-number and the growth form therophytes.The most influence of the use factors has the cut frequency on the species number. It is therefore the factor which can be changed at the easiest for a higher species number if one wants to convert the park lawns into species-rich flower meadows.
I suggest a transformation of the faces into meadows which are cut two or three times per year. In order to get a beautifully flourishing meadow, one must seed meager lawn species with the method of the hay flower seeding.
The vegetation of the park lawns in Munich
Jörn KimpelJörn Kimpel