The Earth's interior is composed of four layers, three solid and one liquid—not magma but molten metal, nearly as hot as the surface of the sun. The deepest layer is a solid iron ball, about ...

The layer acts as a skin for the Earth, protecting landscapes and reducing ... Biocrust, also called cryptobiotic soil, is a "community of tiny, dirt-dwelling organisms that form a distinct ...

Soils are becoming severely degraded due to a combination of intensive farming practices and natural processes. As the layer of fertile topsoil thins, it gets increasingly difficult to grow crops ...