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Saturday, December 12, 2009

Intelligent design and ecology: Environmental change via biosphere feedback mechanisms

British physicist David Tyler writes at Access Research Network (10 December 2009):

With millions of eyes on Copenhagen, this seems an appropriate time to ask whether ID thinking has any relevance to understanding the Earth's environment. Can design concepts help us weigh the diverse and often conflicting messages? I think ID is helpful, because features of the Earth's environments and ecologies start to take on new meaning. In this blog, I am thinking particularly of negative feedback mechanisms. Human design engineers will use negative feedback to promote stability and positive feedback to amplify an input signal. They select the mechanisms they need to achieve the desired effect. By analogy, if the Earth is designed for life, we would expect to see negative feedback mechanisms predominating to achieve stable environments. What do we find?

In the scientific news recently are two research papers relevant to biological feedback mechanisms. The first concerns the quaking aspen (Populus tremuloides), a dominant species in many northern forest ecosystems. "Aspen growth has increased an average of 53% over the past five decades, primarily in response to the 19.2% rise in ambient CO2 levels." "Trees are already responding to a relatively nominal increase in atmospheric carbon dioxide over the past 50 years," says Rick Lindroth, a UW-Madison professor of ecology and an expert on plant responses to climate change. [. . .] The study's findings are important as the world's forests, which cover about 30 percent of the Earth's land surface, play an important role in regulating climate and sequestering greenhouses gases. The forests of the Northern Hemisphere, in particular, act as sinks for carbon dioxide, helping to offset the increase in levels of the greenhouse gas, widely viewed as a threat to global climate stability. A second study is concerned with the impact of fertilisers on the species diversity of grasslands. These chemicals more than double the availability of nitrogen and whilst this stimulates some plants to thrive, others are quickly out-competed and they die off. "In a long-term open-air experiment, grassland assemblages planted with 16 species were grown under all combinations of ambient and elevated CO2 and ambient and elevated N. Over 10 years, elevated N reduced species richness by 16% at ambient CO2 but by just 8% at elevated CO2. This resulted from multiple effects of CO2 and N on plant traits and soil resources that altered competitive interactions among species. Elevated CO2 thus ameliorated the negative effects of N enrichment on species richness."

These are but two examples of negative feedback to promote stability. There have been many examples like this in the past, and there will be many more to come. Examples of positive feedback are rare. The effect this has in my mind is to reinforce the thought that the Earth's environments and ecosystems have a robustness about them. This means that when a catastrophe comes, like the eruption of Mt St Helens volcano, recolonisation rarely takes as long as was first anticipated. Whilst this does not prove the Earth is designed, the marks of design are easy to find and the evidence is fully consistent with design.
Go here for the rest.

This reminds me of something that Sarah Mims, daughter of Forrest (one of 50 best brains in science) Mims discovered a couple of years ago, that fungus spores travel on smoke from forest fires, establishing themselves in non-burnt-out zones. Here's more. Sarah Mims has the unusual distinction of being the lead author of a science paper* while still in high school.

Anyway, I'm one hundred per cent in favour of better home and planet, but would like to help out with a recycling program for "The End Is Near" sandwich boards, which too many people wear these days. Things have been worse. I remember when pollution particles collected on the windowsill outside my apartment in Toronto in 1970. Now, it's just bugs or snow.

*Sarah A. Mims and Forrest M. Mims III, Fungal spores are transported long distances in smoke from biomass fires, Atmospheric Environment 38, 651-655 (2004).

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