Elsevier

Ecological Indicators

Volume 28, May 2013, Pages 48-53
Ecological Indicators

The properties of the ecological hierarchy and their application as ecological indicators

https://doi.org/10.1016/j.ecolind.2012.04.010Get rights and content

Abstract

After a short overview of the hierarchical organization, that characterizes ecological systems, a quantification of the openness of the various hierarchical levels is introduced. By the use of statistical calculations, it is furthermore shown that the random variations due to environmental disturbances in one level of the hierarchy are averaged and therefore result in less variations or disturbances in the next level. Random disturbances are with other words damped when we go up through the hierarchical levels, which obviously is a clear advantage by the hierarchical organization. Thus it is shown that diversity at all levels has the consequences of ensuring a more stable system and less sensitive to environmental disturbances. This is a result that is in contradiction to earlier findings of May, 1973, May, 1981. Approximate calculations of this damping effect can be carried out. The level out effects of the hierarchical organization and the recovery time makes it possible for ecosystems to cope with the relationship between the frequency and the magnitude of the disturbances. These important properties that are crucial for the reactions of the various hierarchical levels to the impacts on ecosystems, are applied in a discussion of the choice of ecological indicators and the applicability of these indicators are demonstrated. The presented hierarchical properties entail that biodiversity on all hierarchical levels is a very important ecological indicator, which is the core topic for the discussion, that summarizes the results and conclusions.

Section snippets

Introduction: the hierarchical organization

The ecosphere is organized hierarchically and may be briefly described as going from molecules, via cells, tissues, organs, individuals, species, populations, communities, ecosystems, landscapes, regions to the ecosphere. The biological hierarchy is easy to observe. The biochemical processes take place in the cells, which have molecular components and structure via the genomes not only to control the processes, but also to protect the genome itself by membranes. In vertebrates, there are many

Interactions between the hierarchical levels

Fig. 2 shows how the processes on one level of the hierarchy determine the conditions in the next level immediately above and how a level regulates and controls a lower level by feedbacks. For a strict thermodynamic interpretation of the relations in such systems see Nielsen (2009). A specific level consists of interacting and cooperative entities that are again in turn integrated as components in a higher organizational level. The interaction of the entities in one level produce an integral

The frequency of disturbances

The magnitude of variations, disturbances and catastrophic events has a frequency that varies according to the power law (see Bak, 1996). The frequency, F, as function of the magnitude, M, is therefore expressed by the following equationF=a*MbAn example is the distribution of earthquake intensities. Fig. 3 shows as an example the frequency versus the earthquake intensities (M) in the Richter scale (which is logarithmic) in a district in U.S. with many earthquakes taken place during a decade.

Selection of indicators that can account for the hierarchical properties

Let us consider a landscape that has a size of 100 km × 100 km = 10,000 km2. If it consists of only one ecosystem, an agricultural wheat field, the landscape is very vulnerable to random disturbances as for instance the weather and pests. If it consists let us say of 100 different ecosystems: wetlands, forests, grasslands, agricultural fields preferably of different types, lakes and ponds, river and streams, the landscape would be much less vulnerable to drought or pest attack. It is probably accepted

Summary and conclusions

It has been shown how it is possible to quantify openness and thereby understand the dynamics on the various levels of the ecological hierarchy. The ecological hierarchy provides all the levels of the hierarchy including the ecosystems and landscapes with very important properties. The higher levels can benefit from the more dynamic lower levels and at the same time provide important regulations of the lower levels. The lower levels may due to their dynamic change more radically by random

References (25)

  • S.N. Nielsen

    Thermodynamics of an ecosystem interpreted as a hierarchy of embedded systems

    Ecol. Model.

    (2000)
  • B.C. Patten

    Energy, emergy and environs

    Ecol. Model.

    (1992)
  • E. Allen

    More diverse plant communities have a higher functioning over time due to turnover in complementary dominant species

    Proc. Natl. Acad. Sci. U.S.A.

    (2011)
  • T.F.H. Allen et al.

    Hierarchy, Perspectives for Ecological Complexity

    (1982)
  • P. Bak

    How Nature Works

    (1996)
  • P.R. Ehrlich et al.

    Extinction: the causes and consequences of the disappearance of species

    (1981)
  • P.R. Ehrlich et al.

    The value of biodiversity

    Ambio

    (1992)
  • S.E. Jørgensen et al.

    A New Ecology

    (2007)
  • S.E. Jørgensen

    Introduction to Systems Ecology

    (2012)
  • Kay, J.J., 1984. Self Organization in Living Systems [Ph.D. Thesis]. Systems Design Engineering, University of...
  • W.E. Kunin et al.

    Does biodiversity matter?

  • R.M. May

    Stability and Complexity in Model Ecosystems

    (1973)
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