A Micro Mystery

Dispatch by Emma Rollins

Rising only millimeters high, biocrust, a partnership between cyanobacteria, lichen, moss, fungi and algae, should not be overlooked. However small it plays a key role in dry land habitats that make up 40% of the terrestrial world. Despite its minimal stature it alone has attracted scientists from around the globe to a conference here in Moab Utah, BIOCRUST 3. Each scientist, steps up to the mike, many with their shirt rolled above the elbows and quite a few ball caps preset, even indoors. One by one these dedicated biologists, having spent hours kneeling flat-footed on desert soils, share their analysis of the leaf like equivalent covering the soil. Biocrust’s photosynthesize like other plants, adding to the absorption of carbon from the atmosphere and releasing oxygen in exchange. It also plays a key role in nurturing a habitat for other species, even during dormant times when little else is growing. Studies presented found that even under snowpack these crusts miraculously photosynthesis when all else in these deserts lies idle. Biocrust also plays an important role in pioneering landscapes by minimizing erosion, holding water within the soils and fixing nitrogen. This encourages the growth of a more diverse habitat. Something that is important on all lands. 

Zooming out to a larger climatic scale biocrust’s contribution to global temperatures complicates things. Especially considering the vast expanses of public lands in the American West that are dry and create good biocrust habitat. Beginning its life camouflaging into the dry land soils, the crust becomes darker in color later in its successional life. The darker covering absorbs rather than reflects sunlight and heat back into space. However this function is responsible for good as well, helping seeds germinate in colder temperatures to repopulate open stretches. Overall biocrust helps stabilize environments facing increasing uncertainties, if it can survive them itself. Simple things like more frequent but shorter rainfalls can kill biocrust. Mosses, a key component of the crust, open their stomata to absorb water, exposing them the next day to harsh sun versus the monsoon patterns extended wet period common today, even if they offer the same overall volumes of water. 

Keep an eye out for these micro biomes that shape the greater public lands we all share. Remembering that little things hold great value. Walking out onto your public lands, beware not to crush the crust! It may take centuries to grow back, meaning your footprint will stick around. Instead find a heart for the crusty organism that paves a yellow, orange and black-splotched road across the dry lands expanse.