Syndynamics Synchorology Synecology

Small scale vegetation mosaic In the Afro-Alpine region of the Bale mountains (south-east Ethiopia) 3400 m above sea level with shrubby communities (Erica arborea), dwarf shrubby vegetation (different species of Alchemilla and Helichrysum) and Individual giant lobelias (Lobelia rhynchopetalum) on the dry rocky slopes and also In the grassland communities and marshy depressions at the moist foot of the slopes. Photo K. Müller-Hohenstein

In this chapter a new level of organisation is discussed. Consideration of plant ecology, and thus the many aspects between autecology and research into ecosystems, necessarily requires progression from the laboratory to natural conditions. Subsequent to the study of individual plants or plant species under controlled conditions with predominantly experimental treatment, in this chapter, we build on the previous analysis of ecological systems (Chap. 3), which recognise the spatial distribution and communities of plants, including the description and understanding of the relative success of the individual plant (or species) in complex communities.

This goal is linked to synecological questions which have been formulated following the laws of Thienemann. Summarising for plants these state that no plant can exist on its own, only in communities (biogeocenes) in interactions comprising living plants and animals. These communities develop with a limited number of plant species and individuals in a limited space in certain temporal rhythms. It is assumed that it is possible to distinguish between plant communities (phytocenoses).

With the increasing complexity of processes to be considered comes a decreasing ability to make prognoses about development. Synecology is a science of observation, rather than experimentation, mainly because of the spatial as well as the temporal dimensions of the areas of distribution, and of processes to be considered. Synecological experiments are carried out by nature itself, including all anthropogenic influences, which increase the complexity considerably. The task is to recognise patterns in the experimental structure and to describe them, as well as to define the limiting conditions. However, the goal of synecology extends beyond mere description. Comparable to experiments under controlled conditions, explanations are sought; however, quantitative measurements are much more difficult to obtain. Thus, quantitative measurements slip into the background, whilst qualitative assessment gains importance.

In analysing ecosystems (Chap. 3), it became obvious that two aspects are connected with the step into field, conditions which so far have only been marginally addressed. Communities - and of course also plant communities - develop during the course of time and may display directed or cyclic dynamics. Their history and rhythms of development must be known in order to understand their actual structure. Here, the influences of human settlement and management are particularly important. Historical-genetic aspects of plant communities are discussed in Chapter 4.1 as syndynamics. During their development over time, plants and plant communities conquered habitats and expanded into available space. The basis of the spatial distribution of plant communities is discussed in Chapter 4.2 as synchorology. In Chapter 4.3, synecology and biotic interactions between plants and animals are considered on the basis of syndynamics and synchorology.

Because of the complexity, it is not possible to comprehensively describe synecology, only a selection of generalised knowledge of temporal dynamics and stability, of spatial expansion and diversity, as well as of competition and coexistence is presented.

As further literature the textbooks by

• Begon M, Harper JL, Townsend C (1999) Ecology, 3rd ed. Blackwell, Oxford

• Begon M, Mortimer M, Thompson D (1996) Population ecology. A unified study of animals and plants, 3rd ed. Blackwell, Oxford

• Chapin SF III, Matson PA, Mooney HA (2002) Principles of terrestrial ecosystem ecology. Springer, New York

• Crawley MJ (1997) Plant ecology, 2nd ed. Blackwell, Oxford

• Krebs JR, Davies NB (1997) Behavioural Ecology. An evolutionary approach, 4th ed. Blackwell, Oxford

• Odum EP (1971) Fundamentals of ecology, 3rd ed. Saunders, Philadelphia

• Remmert H (1980) Ecology: a textbook. Springer, Berlin Heidelberg New York are recommended.

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