Nostoc commune is a traditional food in China, East Asia, and some African countries. It is also a great candidate to study soil microbial geography and biochemical composition and mineral elements at the species level.
Researchers from Systems Ecology Group of Wuhan Botanical Garden focused on 15 mineral elements of N. commune and investigated the geographical variation of mineral elements of soil microorganisms at the species level in mainland China.
Five elements (P, Cu, Zn, Co, Pb) showed significant geographical variation, which increased with the increase of the distance from the equator, and decreased with the increase of the distance from the prime meridian.
Climate factors (mean annual precipitation and mean annual temperature) explained most of the variation. Except for P, the other mineral elements in N. commune had no significant correlations with the minerals in soil and rainfall.
The variation coefficients of different elements were not significantly correlated with their measured contents and their potential physiological required contents. This mismatching of mineral variation coefficients of Nostoc with their potential physiological required contents do not support the “restrictive element stability hypothesis” of higher plants.
Researchers speculate that the increase in mineral elements or ash may signal that N. commune has an adaptation mechanism for drought and low temperature environments.