Data from Comparing organic carbon bound to different minerals in wetland and upland soils

Here is the data and drawing code  for "comparing organic carbon bound to different minerals in wetland and upland soils". Mineral binding of organic carbon (OC) is vital for soil organic carbon (SOC) persistence. However, the relative importance of two main types of soil minerals - metal oxides and silicate clay - in SOC protection remains unclear, hampering our ability to predict and protect this important pool of persistent SOC. Here, using sequential dissolution by dithionite and hydrofluoric acid, we quantified OC bound to metal oxides versus silicate clay in soils from contrasting environments (i.e., wetlands and uplands).  We find that metal oxides override silicate clay in SOC protection in both wetlands and uplands, and OC bound to soil minerals (especially metal oxides) constitutes a higher fraction of SOC in wetlands than uplands, suggesting an underappreciated role of mineral protection in wetland SOC preservation. Furthermore, using lignin phenol analysis in tandem, we find that silicate clay dissolution may release an addition of ~23% lignin phenols from soils, potentially providing a means to assess ‘hidden’ lignin in mineral matrices. These findings highlight the important role of different soil minerals in the protection of SOC and its components in contrasting terrestrial environments, and advance our understanding of predicting and protecting this important pool of persistent SOC.