Article
Environmental Sciences
Zeshu Zhang, Hubert Montas, Adel Shirmohammadi, Paul T. Leisnham, Masoud Negahban-Azar
Summary: Nonpoint source (NPS) pollution is a global issue, especially in the Chesapeake Bay, where sediment, nitrogen (N), and phosphorus (P) are the main water quality concerns. This study investigated the spatial distribution of NPS hotspots and found that as land cover changes from agriculture to ultra-urban, the distribution of NPS pollution source areas becomes increasingly uniform. The research suggests that control strategies should be adapted based on the major land cover category of study watersheds.
Article
Environmental Sciences
Ryan P. McGehee, Dennis C. Flanagan, Bernard A. Engel
Summary: The WEPP model code was extensively modified to simulate nonpoint source pollutant sourcing and transport in nonuniform hillslopes based on NPS science from SWAT. The modifications included using WEPP's OFE instead of SWAT's HRU for more realistic routing and improving the NPS code base.
INTERNATIONAL SOIL AND WATER CONSERVATION RESEARCH
(2023)
Article
Biodiversity Conservation
Le Li, Mengmeng Gou, Na Wang, Wei Ma, Wenfa Xiao, Changfu Liu, Lumeng La
Summary: This study developed an integrated approach to identify the effects of climate and landscape changes on runoff and nitrate loading in watersheds in the Three Gorges Reservoir area of China. It found that landscape pattern changes primarily affected surface runoff and nitrate load, while baseflow and water yield were mainly influenced by precipitation change. The findings highlight the importance of considering landscape configuration and seasonal climatic characteristics in ecological restoration strategies for effective control of nitrate loss.
ECOLOGICAL INDICATORS
(2021)
Article
Engineering, Civil
Lei Chen, Jiaqi Li, Jiajia Xu, Guowangchen Liu, Wenzhuo Wang, Jing Jiang, Zhenyao Shen
Summary: Scale transformation is crucial for NPS pollution management, improving the efficiency of PMAs identification. Uncertainties lie in the selection of water quality target, assessment point, and hydrological periods. The new framework shows advantages in reducing NPS control area and intensifying watershed management under different scenarios.
JOURNAL OF HYDROLOGY
(2022)
Article
Engineering, Civil
Rajith Mukundan, Rakesh K. Gelda, Mahrokh Moknatian, Xuesong Zhang, Tammo S. Steenhuis
Summary: This study transformed the SWAT-Carbon (C) model to simulate dissolved organic carbon (DOC) from variable source runoff areas in a humid forested watershed in the northeastern United States. The calibrated model accurately simulated streamflow and DOC flux, and showed sensitivity to soil properties and precipitation. The good performance of the model makes it a valuable tool for understanding the influence of climate and watershed management on DOC and developing mitigation strategies.
JOURNAL OF HYDROLOGY
(2023)
Article
Green & Sustainable Science & Technology
Nametso Matomela, Tianxin Li, Peng Zhang, Harrison Odion Ikhumhen, Namir Domingos Raimundo Lopes
Summary: This study assesses the impact of landscape structure on runoff and non-point source pollution (NSP) using different models and algorithms. The results show a significant correlation between landscape structure and pollution distribution, particularly for larger and more aggregated landscapes.
Article
Engineering, Environmental
Minghui Zhang, Lin Wang, Xuda Huang, Zhonghua Yu
Summary: By conducting field surveys and surface accumulation sampling analysis in the Licun River basin in Qingdao, the evaluation model of urban nonpoint source pollution was constructed by revising the land type data and the urban database of the SWAT model. The results showed that nitrate concentration in precipitation was most sensitive to nitrogen loading simulation, and organic P in baseflow was most sensitive to phosphorus loading simulation. The model fit was good, meeting the requirements for runoff, TP, and TN. Additionally, the spatial and temporal distribution characteristics of urban nonpoint source pollution of TN and TP in 2021 were analyzed, with the most polluted month being July in the Licun River basin.
WATER SCIENCE AND TECHNOLOGY
(2023)
Article
Environmental Sciences
Xiong Pan, Zeyu Chen, Wenliang Zhai, Lei Dong, Li Lin, Yi Li, Yuyi Yang
Summary: This study investigates the relationship between 25 antibiotic resistance genes (ARGs) and nonpoint source pollution in the Erhai basin. The results show that while the overall abundance of ARGs in Erhai Lake is low, individual genes like sulfonamide resistance genes are high. Regression analysis reveals that the discharge of nonpoint source pollution significantly affects the distribution of ARGs, with total phosphorus pollution showing a more significant impact than total nitrogen pollution.
ENVIRONMENTAL POLLUTION
(2023)
Article
Automation & Control Systems
Lianbo Ma, Yang Liu, Guo Yu, Xinzhe Wang, Hongwei Mo, Gai-Ge Wang, Yaochu Jin, Ying Tan
Summary: In real-world applications, a specific class of multiobjective optimization problems, known as variable multiobjective optimization problems (VMMOPs), with variable-length and mixed variables, such as the cloud service allocation problem (CSAOPs), have been under-researched. To address this gap, a tailored enhanced decomposition-based algorithm is proposed to handle VMMOPs. The algorithm utilizes a variable-length coding structure to represent the solutions of VMMOPs and incorporates a dimensionality incremental learning strategy to generate representative solutions for training two learning models. Experimental results demonstrate the effectiveness and competitiveness of the proposed method in handling VMMOPs.
IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS
(2023)
Article
Polymer Science
Zhongchen Yang, Yanhong Lou, Hong Pan, Hui Wang, Quangang Yang, Yajie Sun, Yuping Zhuge
Summary: In this study, a biodegradable composite carbon source was added to atrazine-contaminated soil to enhance the bioremediation of excessive nitrate. The addition of a 25 g/kg composite carbon source achieved the optimal nitrate removal performance (92.10%), slightly higher than that with a 5 g/kg composite carbon source (86.15%) (p > 0.05). However, the former also had negative effects, such as significantly increased emissions of N2O and CO2, and a stronger global warming potential. Microbial community analysis showed that the usage of the composite carbon source clearly decreased the richness and diversity of the microbial community, and greatly stimulated nitrogen metabolism and atrazine degradation (p < 0.05). In summary, the application of a 5 g/kg composite carbon source contributed to ensuring bioremediation performance and reducing adverse environmental impacts at the same time.
Article
Thermodynamics
Nanjiang Dong, Tao Zhang, Rui Wang
Summary: This study establishes a multiobjective mixed-variable configuration optimization model for a comprehensive combined cooling, heating, and power energy system, and proposes an efficient generating operator to optimize this model. The experimental results show that the proposed algorithm performs better than other state-of-the-art algorithms.
ENERGY CONVERSION AND MANAGEMENT
(2024)
Article
Agricultural Engineering
Victor Pozzobon, Na Cui, Alissa Moreaud, Emilie Michiels, Wendie Levasseur
Summary: The addition of nitrite triggered growth rate inhibition in Chlorella vulgaris, while there was no impact on the pigment contents. Nitrate uptake rate increased with nitrate content, but nitrite uptake remained constant.
BIORESOURCE TECHNOLOGY
(2021)
Article
Water Resources
Qiang Wu, Hui Yu
Summary: The study identified CSAs in watersheds for NPS pollution management by integrating SWAT model and ECM method to quantify S factors. It found that using multi-factors with different weights was more accurate for CSA identification, providing a sound basis for future decision-making.
HYDROLOGY RESEARCH
(2021)
Article
Environmental Sciences
Yanting Hu, Zisheng Xing, Fu Zhang, Qing Tian, Nasem Badreldin, Jinmei Zhao
Summary: Agriculture-related nonpoint source pollution is a global issue, and estimating pollutant sources at the basin scale remains challenging. This study analyzed the impact of different land uses on water quality using long-term observational data and identified significant pollutants. Pollutants were mainly discharged through hillslope areas, and pollutant concentrations varied with pollutants and land uses. Implementing soil and water conservation measures can mitigate pollutants to some extent.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Environmental Sciences
Lei Tan, Guishan Yang, Qing Zhu, Rongrong Wan, Kun Shi
Summary: Payment for ecosystem services (PES) is crucial in managing the relationship between ecosystem services supply and demand in watersheds. This study developed an approach that combines observation data, hydrological modeling, and cost-benefit analysis to address the gaps in the supply and demand of soil retention services for PES. The results showed that cropland reforestation can effectively reduce downstream sediment loads, but its efficiency is influenced by factors such as area, slope, and location.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)