Sedimentary Marl mudstone as a substrate in a xeric environment revealed by microbiome analysis

Gypsum soil layer is composed primarily of CaCO3 and is an important pedologic and geomorphologic element known as Marl, extensively dispersed in slopes and ridges in the Israeli northern Negev Desert. The wide Marl soil layer areas are barren, with well-developed streamsides and no perennial vegetation cover. Soil systems in the Negev desert have been widely studied, yet very little information was collected on Marl soils, and even less on the microbiome present in the Negev desert in Israel. Thus, an evaluation of the microbial-community inhabitants in a Marl soil layer was conducted in an attempt to distinguish between Marl with surface green mat and bare Marl soil layer. The objective of this study was to investigate the microbiome and abiotic components of the upper layer (0-5 cm) of Marl and Marl-with-green mat soil collected in the Negev Desert.