Activity 5
Plant function and the environment
In Module 3, much of the material we are looking at falls within the discipline of plant physiological ecology or ecophysiology. This discipline describes physiological processes or mechanism that determine observed ecological patterns. Plant ecology provides us with information on distribution and abundance of plants, competition between species and interactions with the environmental– ecophysiology seeks to understand the underlying physiological mechanisms that determine observed distribution and species assemblages that we observe in nature.
Read through the two introductory readings, Raven et al. (2009) on global ecology and Lambers et al. (2008) who provides us with an overview of ecophysiology, its aims and approaches. This will provide useful background and ways of thinking about ecosystems. Raven et al. (2009) is long chapter (download from the open access web site) so focus on the first 15 pages or so of this chapter.
An example of an ecophysiological approach to an observed ecological patterns (evergreen vs deciduous phenology) can be found in the reading Eamus (1998), which is an interesting (hopefully!) analysis of strategies employed by plants to survive the harshness of the seasonal tropics.
Eamus (1998) used an 'economic' analysis approach and conducted a cost-benefit analysis of evergreen vs deciduousness in tree species that are common in the savannas of north Australia. Evergreen species essentially tolerate drought (the dry season) whereas deciduous species avoid drought. What does this tell us about the evolution of the savannas?
Prior et al. (2004) took this approach further and did a comprehensive analysis of tropical Eucalypts – why do the dominate the northern landscapes so comprehensively? What ecophysiological traits do they have that makes them so successful in this combination of climate and soils? Why do other species not perform as well in north Australia?
These papers are peer-reviewed scientific papers, i.e. it has been published only after scrutiny by other, independent experts. It is not as easily digested as a textbook and is not as easy to read, so focus on the introduction and the discussion and conclusions – what are the main points the author is trying to get across? Don’t get caught up in the detail!