Glyphosate primarily undergoes degradation through microbial activity, with additional contributions from abiotic mechanisms, which remain poorly understood. Whether via biotic or abiotic mechanisms (Scheme S1), the degradation of glyphosate may occur through C(2)-N bond cleavage, which forms AMPA (AMPA pathway), a more toxic and resistant metabolite than glyphosate; and/or through C(3)-P bond cleavage (sarcosine pathway), which yields innocuous products (i.e., sarcosine and then glycine). A third degradation pathway (glycine pathway; C(3)-N bond cleavage) has also been proposed due to the inability to detect sarcosine. The abiotic transformation and persistence of glyphosate and its byproducts vary significantly depending on environmental conditions. For example, the half-life (t1/2) of glyphosate ranges widely across soils (t1/2 ≈ 2-174 days). This variation is strongly influenced by adsorption potential. Clay-rich soils with high organic matter content and low pH typically exhibit lower half-lives due to greater glyphosate adsorption. In a model water/Mn oxide catalytic system, which is the most commonly used system in studies of glyphosate oxidation, glyphosate is notably unstable and degrades much faster (t1/2 ≈ 0.19 -0.89 hr). Mn oxides are ubiquitous in soils and sediments, and highly redox-sensitive although fluctuation between oxic and anoxic conditions mainly impact Mn oxidation states in pore waters. Previous studies have shown that factors such as pH, temperature, the presence of oxyanions and metals, redox conditions, solid-to-solution ratio, and initial concentration influence the catalytic activity of Mn oxides (predominantly birnessite) and the associated rates of transformation and pathway selectivity in the abiotic oxidation of glyphosate. Furthermore, different contribution of Mn valences (II, III and IV) impact the redox potential and reactivity of Mn oxide interfaces for transformation and stabilization of organic carbon. Although the abiotic degradation of glyphosate by birnessite (δ-Mn (III,IV) O2) has been extensively studied , there is no study demonstrating how Mn oxides with lower Mn valence states (i.e., hausmannite; Mn3 (II,III) O4) may contribute to adsorption and or degradation of glyphosate.