Subsurface Environmental Research Articles

Application of Gradient-Dependent Optimal Interpolation in Fishery Analysis of Neon Flying Squid (Ommastrephes bartramii) in the Kuroshio–Oyashio Confluence Region

A key issue in fishery forecasting is the collection of high-precision subsurface environmental data. A data assimilation method, named gradient-dependent optimal interpolation, was used to construct the near-real-time vertical temperature and salinity structure of a squid fishery ground based on Argo observations. The results were verified by truth-finding comparisons and applied to analyze the relationship between neon flying squid and the subsurface environment in the Kuroshio–Oyashio Confluence Region. The temperature and salinity differences between the constructed results and survey data were less than ±0.5 °C and ±0.02, respectively. Most of the relative analysis errors were less than the observational errors. Statistical analysis revealed that the most suitable temperature for squid was 18–24 °C at the near-surface (<5 m), although the squid can endure a temperature range from 11 to 12 °C at a depth of 300 m. There was an obvious thermocline in the fishery ground, with a thermocline depth of 65 m and a mean strength of approximately 0.10 °C/m. The regressive relationship between vertical temperature (thermocline parameters) and squid catch per unit effort (CPUE) followed the exponential (Gaussian) function. The most suitable salinity was 33.0–34.2 at depths shallower than 300 m.

Performance expectation of coal waste in permeable reactive barrier for removal of cadmium considering contamination level and pore water velocity

The effectiveness and longevity of permeable reactive barriers (PRBs) depend on the performance of the reactive materials and the subsurface environment. The relationship of the groundwater velocity on performance of coal waste for the heavy metal removal was reported in our previous study. In this study, we investigated the performance and longevity of coal waste as a PRB material for the removal of Cd considering subsurface environmental conditions such as contamination level and groundwater velocity. The artificial groundwater contaminated by Cd were prepared with various concentrations ranging from 10 to 100 mg L−1. Lab-scale column experiments were conducted using coal waste filled columns by injecting the artificial groundwater. The breakthrough curves were analyzed advection dispersion equation coupled with equilibrium sorption model to determine the retardation factor. The Cd breakthrough curves exhibited different retardation with respect to the contamination levels. The Cd transport was more retarded as the contamination level lowered. The relationship between the retardation factor and the contamination levels could be explained with empirical equations based on non-linear sorption isotherms. By adopting the velocity dependency of sorbent performance in our previous study, transport of Cd within coal waste was simulated under various subsurface environmental conditions to construct the longevity function. The function could be used for the longevity prediction of coal waste as a PRB material considering groundwater velocity and contamination level in subsurface environment.

Thermal energy storage with tunnels in different subsurface conditions

Thermal energy storage with tunnels in different subsurface conditions

Aerobic microbial taxa dominate deep subsurface cores from the Alberta oil sands.

Little is known about the microbial ecology of the subsurface oil sands in Northern Alberta, Canada. Biodegradation of low molecular weight hydrocarbons by indigenous microbes has enriched high molecular weight hydrocarbons, resulting in highly viscous bitumen. This extreme subsurface environment is further characterized by low nutrient availability and limited access to water, thus resulting in low microbial biomass. Improved DNA isolation protocols and increasingly sensitive sequencing methods have allowed an in-depth investigation of the microbial ecology of this unique subsurface environmental niche. Community analysis was performed on core samples (n = 62) that were retrieved from two adjacent sites located in the Athabasca Oil Sands at depths from 220 to 320 m below the surface. Microbial communities were dominated by aerobic taxa, including Pseudomonas and Acinetobacter. Only one core sample microbial community was dominated by anaerobic taxa, including the methanogen Methanoculleus, as well as Desulfomicrobium and Thauera. Although the temperature of the bitumen-containing subsurface is low (8°C), two core samples had high fractions of the potentially thermophilic taxon, Thermus. Predominance of aerobic taxa in the subsurface suggests the potential for in situ aerobic hydrocarbon degradation; however, more studies are required to determine the functional role of these taxa within this unique environment.

Reactive transport benchmarks for subsurface environmental simulation

Over the last 20 years, we have seen firsthand the evolution of multicomponent reactive transport modeling and the expanding range and increasing complexity of subsurface applications it is being used to address. There is a growing reliance on reactive transport modeling (RTM) to address some of the most compelling issues facing our planet: climate change, nuclear waste management, contaminant remediation, and pollution prevention. While these issues are motivating the development of new and improved capabilities for subsurface environmental modeling using RTM (e.g., biogeochemistry from cell-scale physiology to continental-scale terrestrial ecosystems, nonisothermal multiphase conditions, coupled geomechanics), there remain longstanding challenges in characterizing the natural variability of hydrological, biological, and geochemical properties in subsurface environments and limited success in transferring models between sites and across scales. An equally important trend over the last 20 years is the evolution of modeling from a service sought out after data has been collected to a multifaceted research approach that provides (1) an organizing principle for characterization and monitoring activities; (2) a systematic framework for identifying knowledge gaps, developing and integrating new knowledge; and (3) a mechanistic understanding that represents the collective wisdom of the participating scientists and engineers. There are now large multidisciplinary projects wheremore » the research approach is model-driven, and the principal product is a holistic predictive simulation capability that can be used as a test bed for alternative conceptualizations of processes, properties, and conditions. Much of the future growth and expanded role for RTM will depend on its continued ability to exploit technological advancements in the earth and environmental sciences. Advances in measurement technology, particularly in molecular biology (genomics), isotope fractionation, and high-resolution X-ray spectroscopy, have created new lines of research that can be used to inform the conceptualization of reactions and rate laws and validate mechanistic models. For example, spectroscopy has identified the oxidation states of key components and elemental distributions at increasingly smaller scales and lower concentrations; molecular biology has progressed from identifying the presence of microbes to characterization of which microbial communities are active and what they are doing (i.e., microbial function), which has led in turn to the identification of active processes under conditions beyond what analytical chemistry can discern; isotope ratios in pore water and solid phases that can be used to distinguish between biotic from abiotic processes, sorption from precipitation, and origin and age of groundwater. The other noteworthy development that is expanding the role of RTM in subsurface environmental modeling is he advance in computational technology that is enabling the simulation of more coupled processes with increasing mechanistic detail. In some cases, this involves the inclusion of more reactive species and/or microbial populations in the simulations; in other cases, the impact is through the ability to achieve high resolution of property distributions over longer simulated times. To achieve these ambitious objectives for subsurface reactive transport simulation, the subsurface science and engineering community is being driven to provide accurate assessments of engineering performance and risk for important issues with far-reaching consequences. As a result, the complexity and detail of subsurface processes, properties, and conditions that can be simulated have significantly expanded. This expansion was enabled, in part, by advances in measurement technology, computing technology, and numerical techniques.« less

Urbanization and subsurface environmental issues: An attempt at DPSIR model application in Asian cities

This paper synthesizes existing information and knowledge on subsurface environments to understand the major cause and effect relationships of subsurface environmental issues by using the DPSIR (Driving force–Pressure–Status–Impact–Response) approach as the framework of analysis. Description is given to the major subsurface environmental issues common among the selected Asian cities (Bangkok, Jakarta, Manila, Osaka, Seoul, Taipei and Tokyo), such as excessive groundwater abstraction, land subsidence and groundwater contamination. The DPSIR framework is used to analyze the issues and problems of subsurface in key stages and suggestions are made for additional indicators to improve our description of the stages of urban development for the future.

Integrated research on subsurface environments in Asian urban areas

The RIHN project “Human impacts on urban subsurface environments” aims to suggest improved development plans of urban centers for human well-being. This will be done by examining reconstructed past changes in urban environments, and by developing integrated nature-social models. Subsurface environmental indicators are developed from the points of view of: (1) human activities; (2) climate change; and (3) character of urban development and social policies. Water, heat, and material environments and transport vectors are being evaluated by a number of different approaches. Some of these include investigating changes in groundwater resources using satellite observations, reconstructing effects of climate change and urbanization using subsurface thermal regimes, and evaluating past contamination patterns from preserved subsurface records. In this overview paper, we describe the current status of urbanization in Asia, subsurface water conditions, material and contaminant transport to surface waters by groundwater, and subsurface thermal anomalies due to the heat island effect. The rapid pace of urbanization in Asia requires that we develop a better understanding of how to deal with environmental impacts, both above and below ground.

Temperature and hydrological variations of the urban environment in the Taipei metropolitan area, Taiwan

In this study, the temperature, precipitation and groundwater level variations and changing patterns with varied time scales are presented for Taipei metropolitan area which consists of the capital city with neighboring counties. Along with the continuous city expansion during the past decades, global warming and heat island effect have generated perceivable negative impacts on environmental and reflect on the climatic and hydrological parameters. In addition to accelerating climate warming, hydrological extremity becomes more evident during the past decades and greatly elevates the risks of drought and floods in the study area. These observations in the Taipei metropolitan area support the common hypothesis that climate variability would increase as climate warms. The air temperature records, in conjunction with hydrological data, provide useful and invaluable information for the ongoing study of subsurface environmental changes resulting from nature and anthropogenic influences in Taipei metropolitan area. The continuing climatic warming and hydrological extremity would create observable impacts on the subsurface environment of Taipei metropolitan area and need to pursue in a fast and efficient pace.

Cretaceous Park? A Commentary on Microbial Paleomics

AstrobiologyVol. 5, No. 2 News & ViewsCretaceous Park? A Commentary on Microbial PaleomicsTori M. HoehlerTori M. HoehlerSearch for more papers by this authorPublished Online:6 Apr 2005https://doi.org/10.1089/ast.2005.5.95AboutSectionsPDF/EPUB ToolsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail FiguresReferencesRelatedDetailsCited ByPreservation of ancestral Cretaceous microflora recovered from a hypersaline oil reservoir11 March 2016 | Scientific Reports, Vol. 6, No. 1Extreme environments in the forests of Ushuaia, Argentina20 November 2007 | Geophysical Research Letters, Vol. 34, No. 22Stratified Communities of Active Archaea in Deep Marine Subsurface SedimentsApplied and Environmental Microbiology, Vol. 72, No. 7Fossil DNA in Cretaceous Black Shales: Myth or Reality? Jaap S. Sinninghe Damsté and Marco J.L. Coolen11 May 2006 | Astrobiology, Vol. 6, No. 2Ancient DNA derived from alkenone-biosynthesizing haptophytes and other algae in Holocene sediments from the Black Sea18 February 2006 | Paleoceanography, Vol. 21, No. 1Microbial Life in Extreme Environments: Linking Geological and Microbiological Processes Volume 5Issue 2Apr 2005 InformationCopyright 2005, Mary Ann Liebert, Inc.To cite this article:Tori M. Hoehler.Cretaceous Park? A Commentary on Microbial Paleomics.Astrobiology.Apr 2005.95-99.http://doi.org/10.1089/ast.2005.5.95Published in Volume: 5 Issue 2: April 6, 2005PDF download