Desert Floor Biological Crust

Biological soil crusts are communities of living organisms on the soil surface in arid and semi arid ecosystems.

Desert floor biological crust.

Cryptobiotic crust is best known and probably most studied from the protected lands of the national parks of the colorado plateau where it forms dark lumpy patches on the red soil. 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. 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. They often cover most of desert soil surfaces and substantially mediate inputs and outputs from desert soils belnap et al.

The knobby black crust here includes lichen mosses green algae microfungi and bacteria but is dominated by cyanobacteria. 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. 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 bscs consist of assemblages of living organisms on soil or rock surfaces in arid and semiarid areas.

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. But it is equally important to desert prairie and tundra ecosystems and also colonizes bare ground in humid temperate environments. 10 6 and protect desert surfaces from erosional shear stresses imposed by overland flow and strong winds allen 2005 2010. Mojave desert plants biological soil crusts webs of life in the desert what and where are biological soil crusts.

Gillettevulnerability of desert biological soil crusts to wind erosion. In many places soil crust comprises over 70 percent of all living ground cover. Biological soil crusts form a living groundcover that is the foundation of desert plant life. Nevertheless collectively they do nothing less than hold together the desert floor.

Typically composed of cyanobacteria fungi lichens and algae they cover a wide variety of undisturbed sonoran desert soils fig. Each of the crust s individual organisms holds little biological significance on its own. Biological soil crusts at tonto national monument. They also perform vital ecosystem functions.