Urban streams play a crucial role in water network connectivity, drainage and urban landscaping, and receive abundant allochthonous dissolved organic matter (DOM), which is derived from nature and human activities. However, the influence of diverse land use types on the spatiotemporal distribution and characteristics of DOM in typical urban streams is still not fully understood. Therefore, the water sample collection and data analysis campaign were carried out in Wuhan in summer and winter. By using parallel factor analysis (PARAFAC) model, two humic-like substances and one protein-like component were eventually identified, and the specific DOM charcteristics of urban streams in industrial area illustrated the impact of allochthonous DOM caused by anthropogenic activities on their properties. The characteristics of DOM presents spatiotemporal distribution differences, and the fluorescence intensity of DOM in summer was significantly higher than that in winter, mainly due to the variation of allochthonous input from precipitation and runoff. Significant differences of the DOM concentration and composition in urban streams under different vegetation coverage were found, indicating that extreme human disturbance and high vegetation coverage can both greatly change DOM characteristics in urban streams. Redundancy analysis (RDA) revealed an indirect driving effect of land use on DOM, and the influence was considerably stronger in summer. The partial least squares structural equation modelling (PLS-SEM) analysis showed that land use can directly affect DOM content of urban streams (-0.147), with anthropogenic land use playing a positive role and natural land use the reverse, and indirectly change DOM concentration by influencing DOM origin (0.128), nutrients (0.022) and heavy metals (0.021). Moreover, human social and economic structure in anthropogenic land use can affect DOM components and sources of urban streams. This study revealed the driving mechanism of land use impact on DOM characteristics and improve our understanding of DOM geochemical cycling in urban streams.
