Preprints
Filtering by Subject: Environmental Engineering
Fully distributed rainfall-runoff modeling using spatial-temporal graph neural network
Published: 2022-01-15
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Hydrology
Recent studies using latest deep learning algorithms such as LSTM (Long Short-Term Memory) have shown great promise in time-series modeling. There are many studies focusing on the watershed-scale rainfall-runoff modeling or streamflow forecasting, often considering a single watershed with limited generalization capabilities. To improve the model performance, several studies explored an integrated [...]
Towards Progressive Geospatial Information Processing on Web Systems: A Case Study for Watershed Analysis in Iowa
Published: 2021-12-26
Subjects: Computer Sciences, Earth Sciences, Environmental Engineering, Environmental Sciences
Geographic Information Systems (GIS) are available as stand-alone desktop applications as well as web platforms for vector- and raster-based geospatial data processing and visualization. While each approach offers certain advantages, limitations exist that motivate the development of hybrid systems that will increase the productivity of users for performing interactive data analytics using [...]
Copper availability governs nitrous oxide accumulation in wetland soils and stream sediments
Published: 2021-12-15
Subjects: Biogeochemistry, Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Geochemistry, Life Sciences
Denitrification is microbially-mediated through enzymes containing metal cofactors. Laboratory studies of pure cultures have highlighted that the availability of Cu, required for the multicopper enzyme nitrous oxide reductase, can limit N2O reduction. However, in natural aquatic systems, such as wetlands and hyporheic zones in stream beds, the role of Cu in controlling denitrification remains [...]
Components and Tidal Modulation of the Wave Field in a Semi-Enclosed Shallow Bay
Published: 2021-12-10
Subjects: Environmental Engineering, Geomorphology, Oceanography
The wave field in coastal bays is comprised of waves generated by far-off storms and waves generated locally by winds inside the bay and regionally outside the bay. The resultant wave field varies spatially and temporally and is expected to control morphologic features, such as beaches in estuaries and bays (BEBs). However, neither the wave field nor the role of waves in shaping BEBs have been [...]
Modeling the Responses of Dissolved Oxygen and Nitrate Concentrations due to Land Use and Land Cover Change Scenarios in a Large Subtropical Reservoir
Published: 2021-09-15
Subjects: Biochemistry, Environmental Engineering, Terrestrial and Aquatic Ecology
Itupararanga reservoir is a large reservoir built in the Southeast of Brazil to support multiple uses, mainly hydropower generation and drinking water supply for almost 1 million people. We applied a process-based biogeochemical model and a distributed basin load model to assess the responses of dissolved oxygen and nitrate concentrations in the Itupararanga reservoir based on three land use and [...]
Integrating Scientific Knowledge into Machine Learning using Interactive Decision Trees
Published: 2021-07-24
Subjects: Civil and Environmental Engineering, Engineering, Environmental Engineering
Decision Trees (DT) is a machine learning method that has been widely used in the geosciences to automatically extract patterns from complex and high dimensional data. However, like any data-based method, the application of DT is hindered by data limitations and potentially physically unrealistic results. We develop interactive DT (iDT) that put the human in the loop and integrate the power of [...]
Toward automating post processing of aquatic sensor data
Published: 2021-07-23
Subjects: Biogeochemistry, Civil Engineering, Environmental Engineering, Environmental Monitoring, Hydrology
Sensors measuring environmental phenomena at high frequency commonly report anomalies related to fouling, sensor drift and calibration, and datalogging and transmission issues. Suitability of data for analyses and decision making often depends on manual review and adjustment of data. Machine learning techniques have potential to automate identification and correction of anomalies, streamlining [...]
Phosphorus Retention in Lakes: A Critical Reassessment of Hypotheses and Static Models
Published: 2021-06-24
Subjects: Engineering, Environmental Engineering, Hydraulic Engineering, Hydrology, Water Resource Management
Various hypotheses and models for phosphorus (P) retention in lakes are reviewed and 39 predictive models are assessed in three categories, namely mechanistic, semi-mechanistic, and strictly-empirical models. A large database consisting of 738 data points is gathered for the analyses. Assessing four pairs of competing hypotheses used in mechanistic models, we found that (i) simulating lakes as [...]
Will it float? Rising and settling velocities of common macroplastic foils
Published: 2021-06-15
Subjects: Environmental Engineering, Hydraulic Engineering
Plastic accumulates in the environment because of insufficient waste handling and the materials' high durability. Better understanding of plastic behaviour in the aquatic environment is needed to estimate transport and accumulation, which can be used for monitoring strategies, prevention measures, and plastic clean-up activities. Plastic transport models benefit from accurate description of [...]
Advancing on the Promises of Techno-ecological Nature-based Solutions: A Framework for Green Technology in Water Supply & Treatment
Published: 2021-06-10
Subjects: Environmental Engineering, Natural Resources Management and Policy, Other Civil and Environmental Engineering, Sustainability, Water Resource Management
Nature-based Solutions (NBS) are increasingly proposed for effectively and adaptively addressing societal challenges such as water security and natural disasters. However, NBS that are exclusively reliant on natural processes are not fit-for-purpose for the provision of safe drinking water—some range of built technology is required. There is a wide spectrum of techno-ecological NBS—“green [...]
Effects of Cone Penetrometer Testing on Shallow Hydrogeology at a Contaminated Site
Published: 2021-06-07
Subjects: Environmental Engineering, Geotechnical Engineering, Systems Biology, Terrestrial and Aquatic Ecology
Penetration testing is a popular and instantaneous technique for subsurface mapping, contaminant tracking, and the determination of soil characteristics. While the small footprint and reproducibly of cone penetrometer testing makes it an ideal method for in-situ subsurface investigations at contaminated sites, the effects to local shallow groundwater wells and measurable influence on monitoring [...]
CO2 capture by pumping surface acidity to the deep ocean
Published: 2021-04-30
Subjects: Chemical Engineering, Climate, Engineering, Environmental Engineering, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The majority of IPCC scenarios call for active CO2 removal (CDR) to remain below 2oC of warm- ing. On geological timescales, ocean uptake regulates atmospheric CO2 concentration, with two homeostats driving CO2 uptake: dissolution of deep ocean calcite deposits and terrestrial weathering of silicate rocks, acting on 1ka to 100ka timescales, respectively. Many current ocean-based CDR proposals [...]
Towards an operational irrigation management system for Sweden with a water-food-energy nexus perspective
Published: 2021-04-14
Subjects: Agriculture, Environmental Engineering
The 2018 drought in Sweden has triggered questions about climate adaptation and mitigation measures, especially in the agricultural sector, which suffered the most. This study applies a water-food-energy nexus modelling framework to evaluate drought impacts on irrigation and agriculture in Sweden using 2018 and 2019 as case studies. A previous water-food-energy nexus model was updated to [...]
Global climate-driven trade-offs between the water retention and cooling benefits of urban greening
Published: 2021-02-24
Subjects: Civil and Environmental Engineering, Construction Engineering and Management, Earth Sciences, Engineering, Environmental Engineering, Environmental Health and Protection, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Sustainability, Water Resource Management
Heat-related mortality and flooding are pressing challenges for the >4 billion urban population worldwide, exacerbated by increasing urbanization and climate change. Urban greening, such as green roofs and parks, can potentially help address both problems, but the geographical variation of the relative hydrological and thermal performance benefits of such interventions are unknown. Here we [...]
Displacing fishmeal with protein derived from stranded methane
Published: 2021-02-23
Subjects: Bioresource and Agricultural Engineering, Civil and Environmental Engineering, Engineering, Environmental Engineering
Methane emitted and flared from industrial sources across the United States is a major contributor to global climate change. Methanotrophic bacteria can transform this methane into useful protein-rich biomass for animal feed. In the rapidly growing aquaculture industry, this can replace ocean-caught fishmeal, reducing demands on over-harvested fisheries. Here, we analyze the economic potential of [...]