Desert Floor Biological Crust

Mojave desert plants biological soil crusts webs of life in the desert what and where are biological soil crusts.

Desert floor biological crust.

Biological soil crusts bscs consist of assemblages of living organisms on soil or rock surfaces in arid and semiarid areas. Although it may not look like it is alike the cryptobiotic crust covering the desert lands of southern utah are vital to the health of the local ecosystem. Biological soil crusts are communities of living organisms on the soil surface in arid and semi arid ecosystems. They are found throughout the world with varying species composition and cover depending on topography soil characteristics climate plant community microhabitats and disturbance regimes biological soil crusts perform important ecological roles including carbon fixation.

Typically composed of cyanobacteria fungi lichens and algae they cover a wide variety of undisturbed sonoran desert soils fig. Biological soil crust is found throughout the world from the colorado plateau s high desert to the arctic. Nevertheless collectively they do nothing less than hold together the desert floor. Since then researchers have investigated many different aspects of these communities and have shown that although small to microscopic biological soil crusts are critical in many ecological processes of deserts.

The influences of crust development soil texture and disturbance journal of arid environments 39 1998 pp. Biological soil crusts at tonto national monument. They often cover most of desert soil surfaces and substantially mediate inputs and outputs from desert soils belnap et al. The paper is titled dynamic cyanobacterial response to hydration and dehydration in a desert biological soil crust arid and semi arid deserts make up about 40 percent of earth s total land mass.

In many places soil crust comprises over 70 percent of all living ground cover. But it is equally important to desert prairie and tundra ecosystems and also colonizes bare ground in humid temperate environments. Each of the crust s individual organisms holds little biological significance on its own. Although the soil surface may look like dirt to you it is full of living organisms that are a vital part of desert ecosystems this veneer of life is called a biological soil crust.

But if you stop and look at the ground for a few minutes you may find a diverse community of tiny organisms all working together. Gillettevulnerability of desert biological soil crusts to wind erosion. The knobby black crust here includes lichen mosses green algae microfungi and bacteria but is dominated by cyanobacteria. They also perform vital ecosystem functions.