TY - JOUR
T1 - Hybrid WT–CNN–GRU-based model for the estimation of reservoir water quality variables considering spatio-temporal features
AU - Zamani, Mohammad G.
AU - Nikoo, Mohammad Reza
AU - Al-Rawas, Ghazi
AU - Nazari, Rouzbeh
AU - Rastad, Dana
AU - Gandomi, Amir H.
N1 - Copyright © 2024 Elsevier Ltd. All rights reserved.
PY - 2024/5/1
Y1 - 2024/5/1
N2 - Water quality indicators (WQIs), such as chlorophyll-a (Chl-a) and dissolved oxygen (DO), are crucial for understanding and assessing the health of aquatic ecosystems. Precise prediction of these indicators is fundamental for the efficient administration of rivers, lakes, and reservoirs. This research utilized two unique DL algorithms—namely, convolutional neural network (CNNs) and gated recurrent units (GRUs)—alongside their amalgamation, CNN-GRU, to precisely gauge the concentration of these indicators within a reservoir. Moreover, to optimize the outcomes of the developed hybrid model, we considered the impact of a decomposition technique, specifically the wavelet transform (WT). In addition to these efforts, we created two distinct machine learning (ML) algorithms—namely, random forest (RF) and support vector regression (SVR)—to demonstrate the superior performance of deep learning algorithms over individual ML ones. We initially gathered WQIs from diverse locations and varying depths within the reservoir using an AAQ-RINKO device in the study area to achieve this. It is important to highlight that, despite utilizing diverse data-driven models in water quality estimation, a significant gap persists in the existing literature regarding implementing a comprehensive hybrid algorithm. This algorithm integrates the wavelet transform, convolutional neural network (CNN), and gated recurrent unit (GRU) methodologies to estimate WQIs accurately within a spatiotemporal framework. Subsequently, the effectiveness of the models that were developed was assessed utilizing various statistical metrics, encompassing the correlation coefficient (r), root mean square error (RMSE), mean absolute error (MAE), and Nash-Sutcliffe efficiency (NSE) throughout both the training and testing phases. The findings demonstrated that the WT–CNN–GRU model exhibited better performance in comparison with the other algorithms by 13% (SVR), 13% (RF), 9% (CNN), and 8% (GRU) when R-squared and DO were considered as evaluation indices and WQIs, respectively.
AB - Water quality indicators (WQIs), such as chlorophyll-a (Chl-a) and dissolved oxygen (DO), are crucial for understanding and assessing the health of aquatic ecosystems. Precise prediction of these indicators is fundamental for the efficient administration of rivers, lakes, and reservoirs. This research utilized two unique DL algorithms—namely, convolutional neural network (CNNs) and gated recurrent units (GRUs)—alongside their amalgamation, CNN-GRU, to precisely gauge the concentration of these indicators within a reservoir. Moreover, to optimize the outcomes of the developed hybrid model, we considered the impact of a decomposition technique, specifically the wavelet transform (WT). In addition to these efforts, we created two distinct machine learning (ML) algorithms—namely, random forest (RF) and support vector regression (SVR)—to demonstrate the superior performance of deep learning algorithms over individual ML ones. We initially gathered WQIs from diverse locations and varying depths within the reservoir using an AAQ-RINKO device in the study area to achieve this. It is important to highlight that, despite utilizing diverse data-driven models in water quality estimation, a significant gap persists in the existing literature regarding implementing a comprehensive hybrid algorithm. This algorithm integrates the wavelet transform, convolutional neural network (CNN), and gated recurrent unit (GRU) methodologies to estimate WQIs accurately within a spatiotemporal framework. Subsequently, the effectiveness of the models that were developed was assessed utilizing various statistical metrics, encompassing the correlation coefficient (r), root mean square error (RMSE), mean absolute error (MAE), and Nash-Sutcliffe efficiency (NSE) throughout both the training and testing phases. The findings demonstrated that the WT–CNN–GRU model exhibited better performance in comparison with the other algorithms by 13% (SVR), 13% (RF), 9% (CNN), and 8% (GRU) when R-squared and DO were considered as evaluation indices and WQIs, respectively.
KW - Convolutional neural networks (CNNs)
KW - Gated recurrent units (GRUs)
KW - Hybrid models
KW - Water quality assessment
KW - Wavelet transform (WT)
UR - http://www.scopus.com/inward/record.url?scp=85189752793&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85189752793&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/f8cf3a03-9d9f-3a9a-acdf-98db31c738a5/
U2 - 10.1016/j.jenvman.2024.120756
DO - 10.1016/j.jenvman.2024.120756
M3 - Article
C2 - 38599080
AN - SCOPUS:85189752793
SN - 0301-4797
VL - 358
JO - Journal of Environmental Management
JF - Journal of Environmental Management
M1 - 120756
ER -