Academic Journal
Machine-learning based approach to examine ecological processes influencing the diversity of riverine dissolved organic matter composition
| العنوان: | Machine-learning based approach to examine ecological processes influencing the diversity of riverine dissolved organic matter composition |
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| المؤلفون: | Müller, Moritz, D’Andrilli, Juliana, Silverman, Victoria, Bier, Raven L., Barnard, Malcolm A., Lee, Miko Chang May, Richard, Florina, Tanentzap, Andrew J., Wang, Jianjun, de Melo, Michaela, Lu, YueHan |
| المصدر: | Frontiers in Water, 6 |
| بيانات النشر: | Frontiers |
| سنة النشر: | 2024 |
| المجموعة: | Carolina Digital Repository (UNC - University of North Carolina) |
| مصطلحات موضوعية: | Ecosystem properties, random forest, FTICR-MS, DOM, River networks, Molecular composition, Cluster analysis |
| الوصف: | Dissolved organic matter (DOM) assemblages in freshwater rivers are formed from mixtures of simple to complex compounds that are highly variable across time and space. These mixtures largely form due to the environmental heterogeneity of river networks and the contribution of diverse allochthonous and autochthonous DOM sources. Most studies are, however, confined to local and regional scales, which precludes an understanding of how these mixtures arise at large, e.g., continental, spatial scales. The processes contributing to these mixtures are also difficult to study because of the complex interactions between various environmental factors and DOM. Here we propose the use of machine learning (ML) approaches to identify ecological processes contributing toward mixtures of DOM at a continental-scale. We related a dataset that characterized the molecular composition of DOM from river water and sediment with Fourier-transform ion cyclotron resonance mass spectrometry to explanatory physicochemical variables such as nutrient concentrations and stable water isotopes (2H and 18O). Using unsupervised ML, distinctive clusters for sediment and water samples were identified, with unique molecular compositions influenced by environmental factors like terrestrial input and microbial activity. Sediment clusters showed a higher proportion of protein-like and unclassified compounds than water clusters, while water clusters exhibited a more diversified chemical composition. We then applied a supervised ML approach, involving a two-stage use of SHapley Additive exPlanations (SHAP) values. In the first stage, SHAP values were obtained and used to identify key physicochemical variables. These parameters were employed to train models using both the default and subsequently tuned hyperparameters of the Histogram-based Gradient Boosting (HGB) algorithm. The supervised ML approach, using HGB and SHAP values, highlighted complex relationships between environmental factors and DOM diversity, in particular the existence of dams upstream, ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| Relation: | https://doi.org/10.17615/s1qh-g092; https://cdr.lib.unc.edu/downloads/cz30q483t?file=thumbnail; https://cdr.lib.unc.edu/downloads/cz30q483t |
| DOI: | 10.17615/s1qh-g092 |
| الاتاحة: | https://doi.org/10.17615/s1qh-g092 https://cdr.lib.unc.edu/downloads/cz30q483t?file=thumbnail https://cdr.lib.unc.edu/downloads/cz30q483t |
| رقم الانضمام: | edsbas.8D1BCD4 |
| قاعدة البيانات: | BASE |
| DOI: | 10.17615/s1qh-g092 |
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