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Physics-informed machine learning algorithms for forecasting sediment yield: an analysis of physical consistency, sensitivity, and interpretability
2024
El Bilali, A. | Brouziyne, Youssef | Attar, O. | Lamane, H. | Hadri, A. | Taleb, A.
The sediment transport, involving the movement of the bedload and suspended sediment in the basins, is a critical environmental concern that worsens water scarcity and leads to degradation of land and its ecosystems. Machine learning (ML) algorithms have emerged as powerful tools for predicting sediment yield. However, their use by decision-makers can be attributed to concerns regarding their consistency with the involved physical processes. In light of this issue, this study aims to develop a physics-informed ML approach for predicting sediment yield. To achieve this objective, Gaussian, Center, Regular, and Direct Copulas were employed to generate virtual combinations of physical of the sub-basins and hydrological datasets. These datasets were then utilized to train deep neural network (DNN), conventional neural network (CNN), Extra Tree, and XGBoost (XGB) models. The performance of these models was compared with the modified universal soil loss equation (MUSLE), which serves as a process-based model. The results demonstrated that the ML models outperformed the MUSLE model, exhibiting improvements in Nash–Sutcliffe efficiency (NSE) of approximately 10%, 18%, 32%, and 41% for the DNN, CNN, Extra Tree, and XGB models, respectively. Furthermore, through Sobol sensitivity and Shapley additive explanation–based interpretability analyses, it was revealed that the Extra Tree model displayed greater consistency with the physical processes underlying sediment transport as modeled by MUSLE. The proposed framework provides new insights into enhancing the accuracy and applicability of ML models in forecasting sediment yield while maintaining consistency with natural processes. Consequently, it can prove valuable in simulating process-related strategies aimed at mitigating sediment transport at watershed scales, such as the implementation of best management practices.
Mostrar más [+] Menos [-]Quantitative assessment of sediment delivery and retention in four watersheds in the Godavari River Basin, India, using InVEST model — an aquatic ecosystem services perspective
2022
Kantharajan, Ganesan | Govindakrishnan, Panamanna Mahadevan | Singh, Rajeev K. | Estrada-Carmona, Natalia | Jones, Sarah K. | Singh, Achal | Mohindra, Vindhya | Kumar, Nallur Kothanda Raman Krishna | Rana, Jai C. | Jena, Joy Krushna | Lal, Kuldeep Kumar
[Protective utilization of water and land in the Bistrica river basin [Montenegro, Yugoslavia]]
1998
Popovic, V. (Institut za zemljiste, Beograd (Yugoslavia)) | Ivanovic, S. | Ivanovic, S. | Petrovic, P.
In this paper, we are consider processing of soils erosion and his way on protection expoitation of water for population water supply, melioration's systems for irrigation and for strew of manger of the Lim river with the tug and suspend bank (Montenegro, Yugoslavia). We are given suggestions for protective utilization of agricultural and forest lands and the possibilities of water exploitation from Bistrica river (Montenegro, Yugoslavia). That is useful for fishing, irrigation, energetic, tourism and water supply. In this paper, you can meet some suggestions about exploitations of minerals and organic fertilizars that are not toxics and they not any influence on pollution of land and water.
Mostrar más [+] Menos [-]Effect of pluviographic parameters and runoff on suspended sediment concentration in small streams
1998
Stefanovic, J. | Bulajic, Z. (Institut za zemljiste, Beograd (Yugoslavia))
Hydrological, psamological and pluviographical measurements in experimental watershed area in the watershed of River Topciderska (Serbia, Yugoslavia) was analyzed. Interrelations between suspended sediment concentration in streams on the one hand and runoff, rainfall, rainfall intensity and index of previous rainfall on the other hand was came from this analyze. Effects of these parameters on suspended sediment concentration was considered for a single rainfall epizode, during the period of torrential waves and as annual value. Specific coefficients (coefficient of annual rainfall structure and coefficient of annual runoff structure) were used in this paper, with help of them effects of torrential waves and intensity rainfall on average annual suspended sediment concentration were considered.
Mostrar más [+] Menos [-][Lake Prespa [The former Yugoslav Republic of Macedonia]: comparative investigations of watershed and lake water]
2001
Jordanoski, M. | Veljanoska-Sarafiloska, E. (Hidrobioloski zavod, Ohrid (The Former Yugoslav Republic of Macedonia))
Autochthonous and alochthonous fish species in lake Ohrid and its catchement area [The Former Yugoslav Republic of Macedonia]
2001
Talevski, T. (Hidrobioloski zavod, Ohrid (The Former Yugoslav Republic of Macedonia))
In this paper are presented autochthonous and all other alochthonous famous fishes in Lake Ohrid and its catchement area (The Former Yugoslav Republic of Macedonia). Introduction of new species in lakes and rivers in the Former Yugoslav Republic of Macedonia is prohibited, especially in Lake Ohrid and catchement area. The most probable period and possible way of introduction are presented and the reason of that introduction, as well. It is necessary, in the future, more attention to be paid on Lake Ohrid protection from introduction of new species, which may cause big changes in Lake Ohrid dynamics.
Mostrar más [+] Menos [-]Possibilities for mapping pollution in rivers within their basins
1997
Brajkovic, M. (Institut za vodoprivredu "Jaroslav Cerni", Beograd (Yugoslavia)) | Gavrilovic, Z. | Vukmirovic, M. | Dakovic, S.
Problems encountered in evaluating surface water quality arise from the requirements of relevant regulations that these evaluations should be made in the last favourable hydrologic conditions during design flow rate (required minimum flow). However, the major part of measurements of water quality parameters is not performed under such conditions and the result must be corrected for the conditions under required minimum flow. Two possible approaches to solving this problem are presented in this paper and explained using an example of the Juzna Morava river basin up to the Station Korvingrad, Serbia (Yugoslavia). This basin is unhomogeneous regarding its hydrologic characteristics and mass flow of pollutants. The results of analysis are presented in the cartography form using the GIS technology.
Mostrar más [+] Menos [-]Bioaccumulation of per- and polyfluoroalkyl substance in fish from an urban river: Occurrence, patterns and investigation of potential ecological drivers
2022
Macorps, Nicolas | Le Menach, Karyn | Pardon, Patrick | Guérin-Rechdaoui, Sabrina | Rocher, Vincent | Budzinski, Hélène | Labadie, Pierre
Per- and polyfluoroalkyl substances (PFAS) are ubiquitous in aquatic environments and a recent shift toward emerging PFAS is calling for new data on their occurrence and fate. In particular, understanding the determinants of their bioaccumulation is fundamental for risk assessment purposes. However, very few studies have addressed the combined influence of potential ecological drivers of PFAS bioaccumulation in fish such as age, sex or trophic ecology. Thus, this work aimed to fill these knowledge gaps by performing a field study in the Seine River basin (France). Composite sediment and fish (European chub, Squalius Cephalus) samples were collected from four sites along a longitudinal transect to investigate the occurrence of 36 PFAS. Sediment molecular patterns were dominated by fluorotelomer sulfonamidoalkyl betaines (i.e. 6:2 and 8:2 FTAB, 46% of ∑PFAS on average), highlighting the non-negligible contribution of PFAS of emerging concern. C₉–C₁₄ perfluoroalkyl carboxylic acids, perfluorooctane sulfonic acid (PFOS), perfluorooctane sulfonamide (FOSA) and 10:2 fluorotelomer sulfonate (10:2 FTSA) were detected in all fish samples. Conversely, 8:2 FTAB was detected in a few fish from the furthest downstream station only, suggesting the low bioaccessibility or the biotransformation of FTABs. ∑PFAS in fish was in the range 0.22–3.8 ng g⁻¹ wet weight (ww) and 11–140 ng g⁻¹ ww for muscle and liver, respectively. Fish collected upstream of Paris were significantly less contaminated than those collected downstream, pointing to urban and industrial inputs. The influence of trophic ecology and biometry on the interindividual variability of PFAS burden in fish was examined through analyses of covariance (ANCOVAs), with sampling site considered as a categorical variable. While the latter was highly significant, diet was also influential; carbon sources and trophic level (i.e. estimated using C and N stable isotope ratios, respectively) equally explained the variability of PFAS levels in fish.
Mostrar más [+] Menos [-]Integrating land cover, point source pollution, and watershed hydrologic processes data to understand the distribution of microplastics in riverbed sediments
2022
Baraza, Teresa | Hernandez, Natalie F. | Sebok, Jack N. | Wu, Chin-Lung | Hasenmueller, Elizabeth A. | Knouft, Jason H.
Microplastics are emerging contaminants ubiquitously distributed in the environment, with rivers acting as their main mode of transport in surface freshwater systems. However, the relative importance of hydrologic processes and source-related variables for benthic microplastic distribution in river sediments is not well understood. We therefore sampled and characterized microplastics in river sediments across the Meramec River watershed (eastern Missouri, United States) and applied a hydrologic modeling approach to estimate the relative importance of river discharge, river sediment load, land cover, and point source pollution sites to understand how these environmental factors affect microplastic distribution in benthic sediments. We found that the best model for the Meramec River watershed includes both source-related variables (land cover and point sources) but excludes both hydrologic transport-related variables (discharge and sediment load). Prior work has drawn similar and dissimilar conclusions regarding the importance of anthropogenic versus hydrologic variables in microplastic distribution, though we acknowledge that comparisons are limited by methodological differences. Nevertheless, our findings highlight the complexity of microplastic pollution in freshwater systems. While generating a universal predictive model might be challenging to achieve, our study demonstrates the potential of using a modeling approach to determine the controlling factors for benthic microplastic distribution in fluvial systems.
Mostrar más [+] Menos [-]Microplastics in arid soils: Impact of different cropping systems (Altay, Xinjiang)
2022
Liu, Hao | Wang, Xiyuan | Shi, Qingdong | Liu, Yuying | Lei, Haifeng | Chen, Yutong
Although microplastic pollution in the soil environment is currently an important research topic, few studies have focused on farmland soil in arid regions. This study investigated the abundances, sizes, polymer compositions, and forms of microplastics across nine agricultural plots cultivated with maize, sunflower, and potato (three of each crop) plants to determine the influences of different cropping characteristics and agricultural practices. The study area was within the arid region of the Ulungur River basin in Qinghe County, Altay, Xinjiang, China. The main forms of microplastics were fragments and fibers, and polyethylene was the dominant polymer (91.6%). The microplastic abundance ranged from 11 347 items/kgdw to 78 061 items/kgdw (mean of 52 081.7 items/kgdw). The abundance and proportion of microplastics with a diameter of <0.2 mm were significantly higher in the sunflower and maize plots (i.e., tall crops) than in the potato plots (i.e., short crops) (p < 0.05). This is due to straw residues affecting the migration and recovery of the mulch. The abundance and fragmentation of microplastics were significantly higher in the sunflower and maize plots where plastic mulch was extensively used because these tall crops anchored the mulch near their stem–root systems. The mulch was then slowly aged (e.g., via wind erosion) before being fragmented due to agricultural practices (e.g., mechanical plowing and residue retention). Although microplastics sourced from mulch are probably immobilized by straw residues in the short term, fragile and easily broken pieces of mulch are eventually released into the soil due to agricultural practices. The findings suggest that different cropping characteristics can affect the abundance and fragmentation of microplastics in agricultural soils, even within the same region, and thus the level and type of microplastic pollution. Traditional plastic mulch should be replaced with biodegradable mulch to reduce microplastic pollution in agricultural fields.
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