Water Environmental Change Research Articles

Underwater Communication and Optical Camouflage Ionogels.

Marine animals, such as leptocephalus and jellyfish, can sense external stimuli and achieve optical camouflage in the aquatic environment. Fabricating an intelligent soft sensor that can mimic the capabilities of transparent marine animals and function underwater can enable transformative applications in various novel fields. However, previously reported soft sensors struggle to meet the requirements of adhesion, self-healing ability, optical transparency, and stable conductivity in the aquatic environment. Herein, high-performance ionogels by virtue of ion-dipole and ion-ion interactions between fluorine-rich poly(ionic liquid) and ionic liquid are designed. The hydrophobic dynamic viscoelastic networks provide excellent properties for ionogels, including optical transparency, adjustable mechanical properties, underwater self-healing ability, underwater adhesiveness, conductivity, and 3D printability. A mechanically compliant and visually invisible underwater soft sensor based on ionogel is developed. This sensor can achieve optical camouflage, human-body-motion detection, and barrier-free communication in the aquatic environment. A novel contactless sensing mechanism based on changing the electron transfer pathway is proposed. Several interesting functions, such as detection of water environment changes, recognition of objects, delivery of information, and even identification of human standing posture can be realized. Importantly, the ionogel sensor can avoid fatigue and physical damage in the sensing process.

An Implementation of IoT and Data Analytics in Smart Agricultural System – A Systematic Literature Review

India is a country that depends on agriculture, where about half the population relies heavily on agriculture for their livelihood. However, most of the practices undertaken in the agricultural process are not for profit and yield favorable. It should upgrade with current technologies to boost seed quality, check soil infertility, check the water level, environmental changes, and market price prediction, and achieve in agriculture sensitivity of faults and background understanding. The advancement in technology and developments is seen as a significant aspect in their financial development and agricultural production growth. The Internet of Things (IoT), Wireless Sensor Networks (WSN), and data analytics accomplish these upgrades. These technologies help in providing solutions to agricultural issues such as resource optimization, agricultural land monitoring, and decision-making support, awareness of the crop, land, weather, and market conditions for farmers. Smart agriculture is based on data from sensors, data from cloud platform storage and data from databases, all three concepts need to be implemented. The data are collected from different sensors and stored in a cloud-based back end support, which is then analyzed using proper analytics techniques, and then the relevant information is transferred to a user interface, which naturally supported the decision to conclude. The IoT applications mainly use sensors to monitor the situation, which collects a large size of data every time, so in the case of the Internet of Things (IoT) application, sensors contribute more. Data analytics requires data storage, data aggregation, data processing and data extraction. To retrieve data and information from database, we must use data mining techniques. It acts a significant position in the selection-making process on several agricultural issues. The eventual objective of data mining is to acquire information form data transform it for some advanced use into a unique human-comprehensible format. Big data's role in Agriculture affords prospect to increase the farmers' economic gain by undergoing a digital revolution in this aspect that we examine with precision. This paper includes reviewing a summary of some of the conference papers, journals, and books that have been going in favor of smart agriculture. The type of data required for smart farming system are analyzed and the architecture and schematic diagram of a proposed intelligent farming system are included. It also involves implementing different components of the smart farming system and integrating IoT and data analytics in the smart farming system. Based on the review, research gap, research agendas to carry out further research are identified.

Increasing Shape Bias to Improve the Precision of Center Pivot Irrigation System Detection

Irrigation is indispensable in agriculture. Center pivot irrigation systems are popular means of irrigation since they are water-efficient and labor-saving. Monitoring center pivot irrigation systems provides important information for the understanding of agricultural production, water resources consumption and environmental change. Deep learning has become an effective approach for object detection and semantic segmentation. Recent studies have shown that convolutional neural networks (CNNs) are prone to be texture-biased rather than shape-biased, and increasing shape bias can improve the robustness and performance of CNNs. In this study, a simple yet effective method was proposed to increase shape bias in object detection networks to improve the precision of center pivot irrigation system detection. We extracted edge images of training samples and integrated them into the training data to increase shape bias in the networks. With the proposed shape increasing training scheme, we evaluated and compared PVANET and YOLOv4. Experiments with the images in Mato Grosso have shown that both PVANET and YOLOv4 achieved improved performance, which demonstrated the validity of the proposed method.

A dynamic flux model for analyses of phosphorus exchange between overlying water and sedimentary deposits of a reservoir in the cold area of north China

In this study, to clarify the quantitative relationship between the exchange flux of total phosphorus and water environment factors at the sediment-overlying water interface in reservoirs, and to reveal that the seasonal variation of total phosphorus exchange flux at the sediment-overlying water interface changes when the water environmental factors change in reservoirs located in cold regions, water environment factors including pH, DO, temperature, and others were analyzed. Specifically, in 2018, sediment samples of the Dahekou Reservoir from XilinGol League were collected, and via indoor orthogonal simulation experiments, a mathematical model of the total phosphorus exchange flux at the sediment–overlying water interface and environmental factors was established, i.e., R = 0.791 + 0.018[T] + 0.048[pH] - 0.180[DO] + 0.004[K]. This model was then combined with the input load of total phosphorus in the Luanhe and Tuligen rivers in the upper reaches of the reservoir in order to assess the contribution rate of the total phosphorus release load to the total phosphorus input from the reservoir. The results showed that the total phosphorus release pollutant load in the sediments of the Dahekou Reservoir was 0.297 t/a in 2018. The flux of total phosphorus at the sediment-overlying water interface showed seasonal changes: summer > spring > autumn > winter. The release load of total phosphorus in sediments in spring was 0.014–0.042 t/month, and the contribution rate to the total phosphorus input from the reservoir was 16.67%–26.44%. The contribution rate of total phosphorus release in summer from the sediments to the overlying water was 19.71%–33.56%. Although this was the highest value of the entire year, due to the role of water temperature stratification in the summer, its actual contribution to the total phosphorus input pollution in reservoirs may not be significant. The total phosphorus released from the sediments in autumn was 0.067–0.397 t/month, and the contribution rate to total phosphorus input pollution in the reservoir decreased to 5.28%–11.19%. In winter, the water temperature decreased, and the concentration of dissolved oxygen increased. These changes to the water environment increased the phosphorus release from water to sediment, with the exchange flux of total phosphorus between sediment and water changing from −0.004 to −0.011 t/month.

Azov–Don Water Problem

The article considers the set of water management problems that has formed in the Don Basin in the context of current changes in the hydrological regime of rivers and an increase in the demand for the reliability of water resources available for economic sectors. Despite the decline in production and water consumption, the ecological conditions of water bodies in the basin have not improved, many problems have become more acute, the overall environmental situation has deteriorated, and fish production in the Sea of Azov has decreased. Hydrochemical observations in the Don Basin demonstrate deterioration of water quality. Measures proposed to improve water management situation are discussed. It is shown that the forecasts of water use and changes in water environment made in the 1970s have not proved true. The ways to solving the problem of water supply in the Azov–Don Basin are considered.

Study on New Seagrass Bed at the Coastal Area of Yellow River Estuary in Dong Ying

Seagrass resource is an important part of the Marine ecosystem, eelgrass resources worldwide recession received extensive attention of the world. Through the tracking of Yellow River Estuary in Dong Ying, we found a piece of seaweed bed, new types of seaweed for short eelgrass (Zostera japonica Asch. et Graebn), which are mainly distributed in the intertidal zone. During the investigation, seaweed cover increases by 0.54 km2 to 0.54 km2. In the year to August 2015, the biomass is 322.13 g/m2, stem branch density of 794 plants/m2. The rise and fall of seaweed bed is closely related to the water environment changes. Through the study of multiple environmental factors influence on short eelgrass life state, we found that salinity has enormous influence on the growth of eelgrass. In the five salinity conditions which the temperature is 20 °C, the net oxygen production and the activity of ribulose-1, 5-diphosphate carboxylase were the highest when the salinity was 19.459, and the photosynthesis intensity decreased when the salinity was higher or lower than this value. According to the survey, from 2002 to 2014, the inflow of the Yellow River Estuary increased from less than 5 billion cubic meters to nearly 30 billion cubic meters. Therefore, the increase of the sea water amount of the Yellow River and the decrease of the salinity in the estuarine waters are the important reasons for the growth of the seagrass bed.

Response of the western proto-North Atlantic margin to the early Aptian oceanic anoxic event (OAE) 1a: an example from the Cupido platform margin-Gulf of Mexico, NE Mexico

Integrated microfacies and geochemical analyses conducted on five stratigraphic sections in northeastern Mexico (ancentral western margin of the proto-North Atlantic) reveal major paleoenvironmental changes in shallow water and pelagic environments in the prelude and run-up of the early Aptian oceanic anoxic event (OAE) 1a. During the Barremian–Aptian transition, the replacement of photozoan rudist-coral by mesotrophic/eutrophic orbitolinid-miliolid communities in the Cupido platform occurred in association with increased nutrient input. Thereafter, oligotrophic, photozoan, green algal communities repopulated briefly the carbonate ramp. Microbial-dominated ecosystems and peloidal carbonates with scarce fossils flourished before and during the onset of the OAE 1a, attesting carbonate crisis and highly stressed conditions. Organic-rich sediments deposited under weak reducing conditions in some parts of the platform. Carbonate sedimentation at the end of OAE 1a was characterized by photozoan ooid-dominated facies documenting a recovery phase of marine alkalinity. The studied carbonate platform shows a response mode to OAE 1a marked by continuous carbonate production, presumably protected by the “kettle effect”, but accompanied by significant ecological perturbations and incipient drowning. The documented change shares attributes of both central/southern and northern Tethyan platforms response modes. The OAE 1a deposits in the pelagic setting are characterized by organic-rich, radiolarian-dominated carbonates accumulated under oxygen-restricted bottom water conditions and during enhanced nutrient input linked to intense chemical weathering. The intensity of the trace metal anomalies suggests that volcanic-hydrothermal activity associated with the construction phases of the Ontong Java LIP also influenced the elemental abundance in the proto-Atlantic water mass.

Estimation of Temperature Recovery Distance and the Influence of Heat Pump Discharge on Fluvial Ecosystems

Temperature differences between the atmosphere and river water allow rivers to be used as a hydrothermal energy source. River-water heat pump systems are a relatively non-invasive renewable energy source; however, effluent discharged from the heat pump can cause downstream temperature changes which may impact sensitive fluvial ecosystems. The temperature change associated with heat pump discharge in a river reach was examined using the heat transfer equation in a previous study, but not using models. There were also no studies on the impact of temperature change due to heat pump discharge on river ecosystem elements such as endangered fishes. Therefore, in this study, the water temperature recovery distance of effluent was estimated for a river section in the Han River Basin, Korea, using the heat transfer equation and the Environmental Fluid Dynamic Code (EFDC) model. The water temperature recovery distance was estimated to be 9.7 km using the heat transfer equation and 5 km using the EFDC model in summer. It was also estimated to be 4.5 km using the heat transfer equation and 6.7 km using the EFDC model in winter. Results showed that the water temperature recovery distance results estimated by the heat transfer equation had greater variation than the EFDC model. The water temperature recovery distance could also be used as an objective indicator to decide the reuse of downstream river water. Furthermore, as the river system was found to support an endangered fish species that is sensitive to water environment changes, care should be taken to exclude the habitats of protected species affected by water temperatures within water temperature recovery distance.

Change of Water Environment and Nitrogen Balance in Kinu and Kokai River Basins

Change of Water Environment and Nitrogen Balance in Kinu and Kokai River Basins

Synthesis of flexible cross-linked cryptomelane-type manganese oxide nanowire membranes and their application for U(VI) and Eu(III) elimination from solutions

The efficient elimination of radionuclides from aqueous solutions is crucial for environmental protection from radionuclides’ pollution. The construction of octahedral molecular sieve (OMS-2) nanoporous membranes is of great technical importance for different kinds of applications like purification filter, catalysts, oil separation, seawater desalination and pollutant elimination. The facile synthesis of freestanding materials demonstrated uniform and monodispersed nanostructures and a cross-sectional pattern of the membranes, which is easily recycled in the process of adsorption and separation of pollutants from aqueous solutions. The OMS-2 exhibited rapid adsorption kinetics and high adsorption capacities of U(VI) (348 mg/g) and Eu(III) (106 mg/g) at pH = 5.0 ± 0.1 and T = 298 K. The paper-like membranes still retained the original filiform morphologies and showed extraordinary stability after 6 adsorption cycles. The surface complexation and ion exchange were the main mechanisms for the uptake of radionuclides, and the change of water environment had little influence on radionuclide adsorption efficiency. Based on the high adsorption capacity and excellent recycle ability, the OMS-2 membranes are considered as superior adsorbents for the efficient elimination of metal ions in the decontamination of polluted water.

Recognizing Global Reservoirs From Landsat 8 Images: A Deep Learning Approach

Man-made reservoirs are key components of terrestrial hydrological systems. Identifying the location and number of reservoirs is the premise for studying the impact of human activities on water resources and environmental changes. While complete bottom-up censuses can provide a comprehensive view of the reservoir landscape, they are time-consuming and laborious and are thus infeasible on a global scale. Moreover, it is challenging to distinguish man-made reservoirs from natural lakes in remote sensing images. This study proposes a convolutional neural network (CNN)-based framework to recognize global reservoirs from Landsat 8 imageries. On the basis of the HydroLAKES dataset, a Landsat 8 cloud-free mosaic of 2017 was clipped for each feature (reservoir or lake) and was resized into 224 × 224 patches, which were collected as training and testing samples. Compared to other deep learning methods (Alexnet and VGG) and state-of-the-art traditional machine learning methods (support vector machine, random forest, gradient boosting, and bag-of-visual-words), we found that fine-tuning the pretrained CNN model, ResNet-50, could reach the highest accuracy (91.45%). Application cases in Kansas (USA, North America), Mpumalanga (South Africa, Africa), and Kostanay (Kazakhstan, Asia) resulted in classification accuracies of better than 99%, which showed the applicability of the proposed ResNet-50 model to the extraction of reservoirs from a vast amount of moderate resolution images. The framework that was developed in this paper is the first attempt to combine remote sensing big data and the deep learning technique to the recognition of reservoirs at a global scale.

Tree rings: A key ecological indicator for reconstruction of groundwater depth in the lower Tarim River, Northwest China

AbstractGroundwater is becoming increasingly important in extremely arid areas due to climate change and human activities. Little is known, however, regarding the long‐term dynamics of groundwater due to the lack of long‐term historical records of groundwater depth data. In this study, we investigated the relationship between hydrometeorology and tree rings of Populus euphratica (P. euphratica) and the feasibility of reconstructing historical groundwater depths from these tree rings in the lower reaches of the Tarim River, an extremely arid area in China. Tree‐ring growth of P. euphratica mainly reflected historical changes in regional water environments (including runoff and shallow groundwater), rather than climatic variables (including temperature, precipitation, relative humidity, and sunshine hours). Groundwater depth constituted the key environmental factor for directly controlling P. euphratica growth. Linear regression models using tree rings were developed to reconstruct historical changes of groundwater depths in the calendar year (January–December) and the growing season (April–August) from 1950 to 2015. Results tracked well with the main hydrological events in the study area. Our findings demonstrate that tree rings of P. euphratica are a key and effective ecological indicator for quantitatively reconstructing and elucidating historical changes of groundwater depth in the lower reaches of the Tarim River. Additionally, the suitable sampling range for establishing tree‐ring chronologies of P. euphratica and reconstructing groundwater depth is 0–300 m from the river channel in the lower Tarim River. Taking into consideration the lagged effect between runoff of the Ecological Water Conveyance Project (EWCP), decrease in groundwater and tree growth, we recommend that the optimal implementation time of ecological water conveyance is between the previous September and November in the lower Tarim River. This application will effectively improve the groundwater environment in the current year and ensure the growth of riparian trees.

Diatom-based reconstructions of hydrological variations and the underlying mechanisms during the past ∼520 years in the central Tianshan Mountains

In order to deepen our understanding of water environment-related issues in the central Tianshan Mountains (TCTMs), it is necessary to study the change processes of hydrological variables and the underlying mechanisms within a longer time window that goes beyond the instrumental period. This study focuses on a high-resolution lacustrine sediment core drilled from an alpine lake in TCTMs with a hope that palaeohydrological changes inferred from diatom assemblages may provide an insight on details of water environment evolutions. The diatom inferred temperature was broadly consistent with the temperature records in its adjacent areas, representing a temperature trough during ∼1490 to ∼1835 CE and a general rising trend since ∼1835 CE. The diatom inferred pH (DI-pH) was generally low during ∼1490 to ∼1835 CE, and was high with a declined trend during ∼1835 to ∼2013 CE, being negatively correlated with TN or TOC and positively correlated with carbonate in sediments significantly. The diatom inferred conductivity (DI-Cond) was characterized with a significantly high salinity interval during ∼1490 to ∼1835 CE than that during ∼1835 to ∼2013 CE. The salinity during the past ∼520 years was modulated by interplays among precipitation driven by the Atlantic Multidecadal Oscillations, temperature-dictated evaporation, and temperature-led glacier melting. The water environment changes (lakewater temperature, DI-pH, DI-Cond and diatom assemblages) were identified with a remarkable shift at ∼1835 CE when the temperature began to climb up in TCTMs, implying that climate warming not only exerted influences on water resources but also on water properties in TCTMs.

Analysis on the relationship between water resources and environmental change in Northern Thailand

How do people perceive environmental change when coping with scarcity? Previous studies on scarcity tend to overlook the aspect of perception. By analyzing repeated water conflicts in northern Thailand, this study sheds light on this aspect and solves the puzzle posed by repeated water conflicts in a small watershed.

RECTIFICATION THEORY AND REINFORCEMENT PRACTICE BASED ON THE PRINCIPLE OF COUNTERFORCE CENTER

Like buildings with other types of foundations, buildings with pile foundations can tilt because of irrational designs, imperfections of foundation treatment, poor construction qualities, even the change of water environment during usage, etc. By studying and analyzing the causes for the inclination, this paper has proposed a theory of rectification and reinforcement for buildings with pile foundations based on the principle of counterforce center, which makes building be rectified by changing the counterforce center of pile foundation so that it can be in the same vertical line with the gravity center of upper structure. Then the calculation method was given. Combining with an engineering project, it has been proved that the principle of counterforce center is a good guidance for the rectification and reinforcement for buildings with pile foundations.

Response of photosynthesis, growth and water relations of a savannah-adapted tree and grass grown across high to low CO2.

By the year 2100, atmospheric CO2 concentration ([CO2]a) could reach 800 ppm, having risen from ~200 ppm since the Neogene, beginning ~24 Myr ago. Changing [CO2]a affects plant carbon-water balance, with implications for growth, drought tolerance and vegetation shifts. The evolution of C4 photosynthesis improved plant hydraulic function under low [CO2]a and preluded the establishment of savannahs, characterized by rapid transitions between open C4-dominated grassland with scattered trees and closed forest. Understanding directional vegetation trends in response to environmental change will require modelling. But models are often parameterized with characteristics observed in plants under current climatic conditions, necessitating experimental quantification of the mechanistic underpinnings of plant acclimation to [CO2]a. We measured growth, photosynthesis and plant-water relations, within wetting-drying cycles, of a C3 tree (Vachellia karroo, an acacia) and a C4 grass (Eragrostis curvula) grown at 200, 400 or 800 ppm [CO2]a. We investigated the mechanistic linkages between trait responses to [CO2]a under moderate soil drying, and photosynthetic characteristics. For V. karroo, higher [CO2]a increased assimilation, foliar carbon:nitrogen, biomass and leaf starch, but decreased stomatal conductance and root starch. For Eragrostis, higher [CO2]a decreased C:N, did not affect assimilation, biomass or starch, and markedly decreased stomatal conductance. Together, this meant that C4 advantages in efficient water-use over the tree were maintained with rising [CO2]a. Acacia and Eragrostis acclimated differently to [CO2]a, with implications for their respective responses to water limitation and environmental change. Our findings question the carbon-centric focus on factors limiting assimilation with changing [CO2]a, how they are predicted and their role in determining productivity. We emphasize the continuing importance of water-conserving strategies in the assimilation response of savannah plants to rising [CO2]a.

Integrated assessment and scenarios simulation of water security system in Japan

Water security is one of the most important hot topics facing humanity in the 21st century, as it affects people's lives, property and ecology. Water security system (WSS) consists of three major subsystems: water resource, water environment, and water disasters. Firstly, a set pair analysis (SPA) method is applied to evaluate the WSS in Japan from the spatial dimension. Then, the system dynamics (SD) model is used to simulate water resources, water environment, water disasters, and future changes from 1995 to 2025 from the temporal dimension. Further, this study designs four different scenarios: water resources prioritized scenario, water environment leading scenario, water disaster dominated scenario and balanced scenario to compare with the base scenario. The results show that the current situation of WSS in Japan is good except for the water disasters subsystem in Shikoku. It is also found that a balanced model can achieve not only steady water supply and demand, protect the water environment, and mitigate water disasters, but also maximize the benefits for both the economy and population. This study provides a map for water management and achieving water security in the different administrative divisions of Japan.

Water Environment Change in the Australian Rice-producing Area Caused by Climate Change

Water Environment Change in the Australian Rice-producing Area Caused by Climate Change

Water environment change over the period 2007-2016 and the strategy of fishery improve the water quality of Lake Taihu

太湖水环境是国内外关注的焦点，其生态环境质量影响到流域经济社会发展.2007年太湖水危机事件，催生了对太湖的综合整治.本文基于2007-2016十年对太湖水质与蓝藻水华面积等的监测，分析了太湖水环境的演变趋势.太湖十年水质变化阶段性明显，2008-2012年各项水质指标下降明显，而后趋于平缓，近3年个别指标如总磷、叶绿素a浓度等呈现快速上升的反弹趋势；另外，水质指标在空间上的差异性逐步缩小，原来污染严重的西北部水域水质改善效果较为显著，其正从污水湖向自然湖状态过渡，而原来水质相对较好的东南部水域水质却逐步下降.本文也综述分析了太湖鱼类群落结构变化与水质环境变化的相关性，基于太湖局部水域的鱼类调控实践，提出了太湖现阶段以渔改水的鲢鳙控藻非经典生物操纵与鱼类结构调控的经典生物操纵结合的渔业途径.湖泊富营养化治理需要充分关注到鱼类对湖泊浮游生物和水质变化的重要驱动效应，需要充分考虑到鱼类群落结构优化和食物网调控对环境的改善作用.;Currently,water environment in the Lake Taihu has become one of the focuses due to its importance to the rapid growth of economy and the process of society in the Lake Taihu Basin. Water Crisis of the Lake Taihu in 2007 has resulted in a series of comprehensive treatment program for its eco-environmental improvement. Based on the water quality data from 2007 to 2016, the characteristics and dynamic variation of water environment in the last decade were analyzed. The results showed that the periodic change of water quality in Lake Taihu was obvious. All water quality indexes continued to decline and then leveled off over the period of 2008 to 2012, while certain indexes, such as total phosphorus and chlorophyll-a concentration, showed a rapidly increasing trend in nearly three years. Additionally, the spatial heterogeneity of water quality in the Lake Taihu decreased. As for the heavily polluted northwestern waters, changing from contaminated to natural status, had acquired a massive improvement in the ecological environment, while the water quality of the southeastern waters had gradually deteriorated. Based on the correlation analysis between the fish community structure and water quality variation in Lake Taihu, and combined with the practice of certain fish bio-manipulation projects in local lake regions, a bio-manipulation approach Fishery improve the water quality combined using traditional and non-traditional bio-manipulations was proposed. Eutrophication control in lakes requires sufficiently concern the irreplaceable role of fish in driving plankton community and water quality modification, as well as considering the advantageous effects of structural optimization of fish community and food web manipulation.

Monitoring gas hydrate formation with magnetic resonance imaging in a metallic core holder

Methane hydrate deposits world-wide are promising sources of natural gas. Magnetic Resonance Imaging (MRI) has proven useful in previous studies of hydrate formation. In the present work, methane hydrate formation in a water saturated sand pack was investigated employing an MRI-compatible metallic core holder at low magnetic field with a suite of advanced MRI methods developed at the UNB MRI Centre. The new MRI methods are intended to permit observation and quantification of residual fluids in the pore space as hydrate forms. Hydrate formation occurred in the water-saturated sand at 1500 psi and 4 °C. The core holder has a maximum working pressure of 4000 psi between -28 and 80 °C. The heat-exchange jacket enclosing the core holder enabled very precise control of the sample temperature. A pure phase encode MRI technique, SPRITE, and a bulk T1-T2 MR method provided high quality measurements of pore fluid saturation. Rapid 1D SPRITE MRI measurements time resolved the disappearance of pore water and hence the growth of hydrate in the sand pack. 3D π-EPI images confirmed that the residual water was inhomogeneously distributed along the sand pack. Bulk T1-T2 measurements discriminated residual water from the pore gas during the hydrate formation. A recently published local T1-T2 method helped discriminate bulk gas from the residual fluids in the sample. Hydrate formation commenced within two hours of gas supply. Hydrate formed throughout the sand pack, but maximum hydrate was observed at the interface between the gas pressure head and the sand pack. This irregular pattern of hydrate formation became more uniform over 24 hours. The rate of hydrate formation was greatest in the first two hours of reaction. An SE-SPI T2 map showed the T2 distribution changed considerably in space and time as hydrate formation continued. Changes in the T2 distribution are interpreted as pore level changes in residual water content and environment.