The Upper Crust

It's not just the destruction of plant life and animal habitat that occurs when we bulldoze. It's the death of the biocrust.

Our Zoo's Education Curator, Rick LoBello, sent a link to a Washington Post article by Chris Mooney about a study of the effect of climate change on dryland crust in Colorado. The same effects apply to our dryland here in the Chihuahuan Desert. Although the study is about climate change, the Post does report that "the Proceedings of the National Academy of Sciences says the impact of a warming climate on these ecosystems could be much worse than expected — comparable to humans trampling the landscapes underfoot or driving off-road vehicles across them." [My emphasis]

Trampling or driving or, just bulldozing in preparation for development . . . 

The abstract of the study states: "In drylands worldwide, where plant cover is sparse, large amounts of the ground surface are covered by specialized organisms that form biological soil crusts (biocrusts). Biocrusts fix carbon and nitrogen, stabilize soils, and influence hydrology. Extensive physical disturbance from livestock/human trampling and off-road vehicles is known to destroy biocrusts and alter ecosystem function."

Mooney reports: ". . . the ground is covered by a complex group of organisms collectively called “biocrust” — a combination of mosses and lichens that are in effect glued together by photosynthetic microorganisms called cyanobacteria, which provide structure to the landscape through the carbohydrate molecules they secrete."

What does that mean for those of us just going about our business everyday? Lose the crust and get dust. And dust causes respiratory disease and respiratory disease costs a bundle not just to those who suffer but to our entire society. It impacts employment, taxes, health care, lost labor, energy and water costs, etc. 

We don't see the cyanobacteria or the mosses and lichens when we hike or go off-roading and especially when we flatten a large portion of our desert so that we can develop or pave a road or build a dam . . . We don't realize that an entire desert system of flora and fauna depends on the life of that crust and that includes ourselves.

So, when we do develop, we should develop smart and preserve as much of the crust as we can for the health of the entire ecosystem which includes us.

One last word: the worst damage that fracking does may not be below ground but above ground.  

Further reading: Biological Soil Crusts: Webs of Life in the Desert published by the United States Geological Survey.