Tag Archives: ecosystem collapse

Like a House of Cards

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An empirical attack tolerance test alters the structure and species richness of plant–pollinator networks (2020) Biella et al., Functional Ecology, https://doi.org/10.1111/1365-2435.13642

Image Credit: Adamantios, CC BY-SA 3.0, Image Cropped

The Crux

Put simply, ecosystem function is the process that control how nutrients, energy, and organic matter move through an environment. Think about a forest. You have small plants that are eaten by small animals, small animals that are eaten by larger animals, and those larger animals are eaten by even larger animals. When those animals die, they are broken down and consumed by scavengers, fungi, and bacteria. These processes result in a continuous flow of nutrients and energy through the ecosystem. However, if one link (organism) in this chain breaks (goes extinct), the ecosystem could lose its function, and other species that depend on this cycle could go extinct as well.

The way in which a given ecosystem reacts to or recovers from any negative impact that it sustains is key to understanding how ecosystems function. Classically, this is tested with attack tolerance tests, in which all species on a given trophic level are removed and the ecosystem is then monitored to see how/if it maintains its function. In studies of plant-pollinator networks, this is usually modeled with computers, but studies which use natural systems are lacking. Today’s authors wanted to use a natural plant-pollinator system to see what happens.

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What Exactly Does Ecosystem Collapse Mean?

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The transition of a coral reef to an algal reef as a result of bleaching and overfishing is one of the most readily identifiable examples of a local ecosystem collapse (Image Credit: Stop Adani, CC BY 2.0, Image Cropped)

Fifth of countries at risk of ecosystem collapse, analysis finds

It’s a bleak headline, and one which was plastered all over my Twitter and Facebook feeds at the start of this week. I’m used to grim news about the environment. It’s part of my job. So there’s nothing particularly surprising about this title.

What it does represent though, is another use of a somewhat sensational term that is ill-defined by scientists and poorly understood by the public. We’ve written about such terms in the past, biodiversity and functional extinction being two examples. Here, I’m referring to ‘ecosystem collapse‘. I get the draw to such a term: people need to be alarmed about climate change and the ongoing loss of biodiversity our planet faces. Ecosystem collapse sounds really alarming.

So I thought I’d swim around in the literature a bit and see if I could figure out what we mean when we talk about ecosystem collapse.

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