Presentation on theme: "The vegetation of the park lawns in Munich A diploma thesis in biology about vegetation ecology and city ecology."— Presentation transcript:
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 factors 1 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 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 factors 2 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 factors 2 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 factors 2 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
C. Use factors 2 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 Species number (x) and frequency (y) A. Descriptive statistic Species number Frequency raw data (frequency) B. Analytical statistic mathematical 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 7.96 Park lawns have a small species number.
B. Analytical statistic 3 Results Correlation (PEARSON) – math. relationship when coefficient > 0,5 Disturbance indicatorsFlower meadows Temperature, 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)
B. Analytical statistic 3 Results Regression curve of a biotical factor - number of different sorts of Fabales (x) with species number (y) Number of different sorts of Fabales Species number The species number is strongly positively correlated with the number of legumes
B. Analytical statistic 3 Results Regression curves of the pointer values Light-number and Nitrogen-number (x) with species number (y) Species number Nitrogen-number Species number 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) Number of cuts per year Species number In adornment lawns the species number is higher than in most park lawns.
B. Analytical statistic 3 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 statistic 3 Results Canonical correspondence analysis – ordination of use factors degree of human influence Flower meadowsDisturbance indicators
B. Analytical statistic 3 Results CCA – ordination of use factors and biotical factors degree of human influence Flower meadowsDisturbance indicators
years 4. Discussion 4 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 mowergirder mowerchainsaw
4. Discussion 4 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. Summary 5 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 Kimpel