Andrew N Tyler

• BSc, MSc, PhD
• Head of Department at University of Stirling

In order to improve robustness of remote sensing algorithms for lakes, it is vital to understand the variability of inherent optical properties (IOPs) and their mass-specific representations (SIOPs). In this study, absorption coefficients for particulate and dissolved constituents were measured at 38 stations distributed over a biogeochemical gradi...

The Earth's surface waters are a fundamental resource and encompass a broad range of ecosystems that are core to global biogeochemical cycling and food and energy production. Despite this, the Earth's surface waters are impacted by multiple natural and anthropogenic pressures and drivers of environmental change. The complex interaction between phys...

Radium (226Ra) contamination derived from military, industrial, and pharmaceutical products can be found at a number of historical sites across the world posing a risk to human health. The analysis of spectral data derived using gamma-ray spectrometry can offer a powerful tool to rapidly estimate and map the activity, depth, and lateral distributio...

The Kakhovka Dam explosion is an example of the far-reaching environmental consequences of warfare. The resulting dam collapse released some 14.4 billion cubic meters of water, flooding downstream environments and flushing unknown quantities of debris, pollutants and sediments into the north-western Black Sea. With a combined satellite and hydrolog...

Previous studies typically assumed a constant total organic carbon (OC) storage in the lake water column, neglecting its significant variability within a changing world. Based on extensive field data and satellite monitoring techniques, we demonstrate considerable spatiotemporal variability in OC concentration and storage for 24,366 Chinese lakes d...

Inland and coastal waters provide key ecosystem services and are closely linked to human well-being. In this study, we propose a semi-analytical method, which can be applied to Sentinel-2 MultiSpectral Instrument (MSI) images to retrieve high spatial-resolution total suspended solids (TSS) concentration in a broad spectrum of aquatic ecosystems ran...

Many deltas around the world have recorded a decreasing sediment input, mostly due to retention in dams constructed on the river or in the river basin. The Danube River has recorded a significant decrease of its sediment supply to the Danube Delta and the NW Black Sea. This study uses ²¹⁰Pb and ¹³⁷Cs dating, to investigate the effects of the decrea...

Moisture and potassium deficiency are two of the main limiting variables for squash crop performance in many water-stressed places worldwide. If major output decreases are to be avoided, it is critical to detect signs of crop stress as early as possible in the growth cycle. Proximal remote sensing can be a reliable technique for offering a rapid an...

Satellite remote sensing of chlorophyll-a concentration (chla) in oligotrophic and mesotrophic lakes faces uncertainties from sources such as atmospheric correction, complex inherent optical property compositions, and imperfect algorithmic retrieval. To improve chla estimation in oligo- and mesotrophic lakes, we developed Bayesian probabilistic neu...

Plastics in the river environment are of major concern due to their potential pathways into the ocean, their persistence in the environment, and their impacts on human and marine health. It has been documented that plastic concentrations in riparian environments are higher following major rain events, where plastic can be moved through surface runo...

Remote sensing product uncertainties for phytoplankton chlorophyll-a (chla) concentration in oligotrophic and mesotrophic lakes and reservoirs were characterised across 13 existing algorithms using an in situ dataset of water constituent concentrations, inherent optical properties (IOPs) and remote-sensing reflectance spectra Rrsλ collected from 53...

Estimating the concentration of water constituents by optical remote sensing assumes absorption and scattering processes to be uniform over the observation depth. Using hyperspectral reflectance, we present a method to direct the retrieval of the backscattering coefficient (bb(λ)) from reflectance (> 600 nm) towards wavebands where absorption by wa...

Monitoring strategic agricultural crops in terms of crop growth performance, by accurate cost-effective and quick tools is crucially important in site-specific management to avoid crop reductions. The availability of commercial high resolution satellite images with high resolution (spatial and spectral) as well as in situ spectra measurements can h...

Satellite remote sensing data are important to the study of environment problems at a global scale. The GloboLakes project aimed to use satellite remote sensing data to investigate the response of the major lakes on Earth to environmental conditions and change. The main challenge to statistical modelling is the identification of the spatial structu...

Water is a fundamental global resource that is under threat from climate change and direct human induced interventions. The disparate nature of our inland water bodies coupled by their dynamic nature makes conventional sampling challenging. Earth observation (EO) technologies provide solutions to providing more comprehensive monitoring with a highe...

Satellite remote sensing can provide indicative measures of environmental variables that are crucial to understanding the environment. The spatial and temporal coverage of satellite images allows scientists to investigate the changes in environmental variables in an unprecedented scale. However, identifying spatiotemporal patterns from such images...

Satellite product uncertainty estimates are critical for the further development and evaluation of remote sensing algorithms, as well as for the user community (e.g., modelers, climate scientists, and decision-makers). Optical remote sensing of water quality is affected by significant uncertainties stemming from correction for atmospheric effects a...

DANUBIUS-RI, the International Centre for Advanced Studies on River-Sea Systems, is a distributed research infrastructure (RI) integrating studies of rivers and their catchments, transitional waters such as estuaries, deltas and lagoons, and their adjacent coastal seas. The overall aim is to support the sustainable management of River-Sea Systems b...

One of the global changes affecting River-Sea Systems is the reduction of sediment flux, a direct consequence of human interventions in the river basins. The deltas, especially, record the most striking effects, coastal erosion and habitat degradation. This research assesses the change of sediment flux from the Danube though its Delta into the Blac...

The Earth-observation based products are in the CoastObs portal: https://coastobs.lizard.net. Login details to the portal will be provided after finalising the CoastObs training materials: https://coastobs.eu/e-training Products in the portal include demonstration products of the following parameters: Basic products: Chl-a Suspended matter Turbi...

In site-specific management, rapid and accurate identification of crop stress at a large scale is critical. Radiometric ground-based data and satellite imaging with advanced spatial and spectral resolution allow for a deeper understanding of crop stress and the level of stress in a given area. This research aimed to assess the potential of radiomet...

Common aquatic remote sensing algorithms estimate the trophic state (TS) of inland and nearshore waters through the inversion of remote sensing reflectance (Rrs (λ)) into chlorophyll-a (chla) concentration. In this study we present a novel method that directly inverts Rrs (λ) into TS without prior chla retrieval. To successfully cope with the optic...

Atmospheric correction over inland and coastal waters is one of the major remaining challenges in aquatic remote sensing, often hindering the quantitative retrieval of biogeochemical variables and analysis of their spatial and temporal variability within aquatic environments. The Atmospheric Correction Intercomparison Exercise (ACIX-Aqua), a joint...

Moisture and nitrogen deficiency are major determinant factors for cereal production in arid and semi arid environments. The ability to detect stress in crops at an early stage is crucially important if significant reductions in yield are to be averted. In this context, remotely sensed data has the possibility of providing a rapid and accurate tool...

Surface waters are a fundamental resource. They fulfil key function in global biogeochemical cycles and are core to our water, food and energy security. The rapidly increasing rate of data collection from different Earth observation (EO) missions suitable for observing water bodies has promoted satellite remote sensing (RS) as a more widely recogni...

Soil erosion has been associated with various negative environmental impacts foremost of which is the potential pressure it could impose on global food security. The poor conditions of our agricultural soil can be attributed to years of unsustainable farming practices occurring throughout history that has placed significant pressure on the environm...

Water clarity is a well-established first-order indicator of water quality and has been used globally by water regulators in their monitoring and management programs. Assessments of water clarity in lakes over large temporal and spatial scales, however, are rare, limiting our understanding of its variability and the driven forces. In this study, we...

The Chernobyl nuclear power meltdown that took place in 1986 has left a radioactive contamination legacy that currently severely limits the economic potential of impacted regions including the Polessie State Radioecology Reserve in Southern Belarus. Extensive areas of forested land could potentially become economically viable for firewood and build...

While the global coronavirus crisis impacts society and the economy in a myriad of ways, it provides, what is likely to be, a once in a lifetime opportunity for us to rethink our response to climate change. According to the 2020 Global Risk Register, extreme weather and climate action failure are the two most likely and impactful risks to the globa...

More than three quarters of the Earth's land surface is connected to the ocean by rivers. This natural connection between land and ocean by rivers, estuaries and deltas, as well as coastal seas, is essential for humankind in providing key ecosystem services (incl. food and water). However, the quantity and quality of water and sediment transported...

More than three quarters of the Earth's land surface is connected to the ocean by rivers. This natural connection between land and ocean by rivers, estuaries and deltas, as well as coastal seas, is essential for humankind in providing key ecosystem services (incl. food and water). However, the quantity and quality of water and sediment transported...

DANUBIUS-RI, the International Centre for Advanced Studies on River- Sea Systems, is a distributed environmental research infrastructure on the Roadmap of the European Strategy Forum on Research Infrastructures (ESFRI). DANUBIUS-RI offers a new paradigm in aquatic science: the River- Sea continuum approach. It aims to provide an integrated research...

Water temperature is critical for the ecology of lakes. However, the ability to predict its spatial and seasonal variation is constrained by the lack of a thermal classification system. Here we define lake thermal regions using objective analysis of seasonal surface temperature dynamics from satellite observations. Nine lake thermal regions are ide...

Radioactive particles are physically discrete sources of radioactivity that have been released into the environment as a result of past emergencies, events and practices. As the release of radioactive particles is often unplanned, the source term has not been characterised, and the potential radiation doses have not been prospectively assessed. If...

Details of the instrumentation that can be used for validation of water quality parameters derived from Earth Observation data.

Executive summary and recommendations The EU Water Framework Directive 1 (WFD) is an ambitious legislation framework to achieve good ecological and chemical status for all surface waters and good quantitative and chemical status for groundwater by 2027. A total of 111,062 surface waterbodies are presently reported on under the Directive, 46% of whi...

This Science and Innovation Agenda summarises the scientific and technical framework for the development of DANUBIUS-RI. The International Centre for advanced Studies on River-Sea Systems is a distributed environmental research infrastructure dedicated to River-Sea Systems on the Roadmap of the European Strategy Forum on Research Infrastructures (E...

DANUBIUS-RI’s Mission is to facilitate and contribute excellent science on understanding the continuum from river source to sea to provide interdisciplinary knowledge and data for sustainable management, use and protection of River-Sea Systems.

DANUBIUS-RI will provide the Research Infrastructure (RI) to enable interdisciplinary research along the River-Sea Continuum and within a range of River-Sea Systems (RSS), to facilitate an integrated process and system understanding and to address key societal challenges for a sustainable management of RSS in the future. The DANUBIUS-RI Preparatory...

DANUBIUS-RI will provide the Research Infrastructure (RI) to enable interdisciplinary research along the River-Sea Continuum and within a range of River-Sea Systems (RSS), to facilitate an integrated process and system understanding and to address key societal challenges for a sustainable management of RSS in the future. The DANUBIUS-RI Preparatory...

Numerous algorithms have been developed to retrieve chlorophyll-a (Chla) concentrations (mg m⁻³) from Earth observation (EO) data collected over optically complex waters. Retrieval accuracy is highly variable and often unsatisfactory where Chla co-occurs with other optically active constituents. Furthermore, the applicability and limitations of ret...

To date, several algorithms for the retrieval of cyanobacterial phycocyanin (PC) from ocean colour sensors have been presented for inland waters, all of which claim to be robust models. To address this, we conducted a comprehensive comparison to identify the optimal algorithm for retrieval of PC concentrations in the highly optically complex waters...

DANUBIUS-RI, the International Centre for Advanced Studies on River-Sea Systems, currently brings together around 30 partner organisations from 15 countries coordinated by the Romanian research institute GeoEcoMar. DANUBIUS-RI is a long-term, distributed, interdisciplinary European research infrastructure (RI) integrating studies of rivers and thei...

Evaluation of Sentinel-2 and -3 water quality products over European coastal and transitional waters, including chlorophyll-a, seagrass density, primary productivity, phytoplankton size classes, and harmful algal bloom detection.

Aim The factors controlling macrophyte (aquatic plant) composition are complex, recent research having shown that the well‐studied effects of lake environmental factors (the so‐called “environmental filter”) can be constrained by hydrological and landscape factors. We investigated the factors determining macrophyte composition in lakes over water b...

Statistical downscaling has been developed for the fusion of data of different spatial support. However, environmental data often have different temporal support, which must also be accounted for. This paper presents a novel method of nonparametric statistical downscaling, which enables the fusion of data of different spatiotemporal support through...

Eutrophication of inland waters is considered a serious global environmental problem. Satellite remote sensing (RS) has been established as an important source of information to determine the trophic state of inland waters through the retrieval of optically active water quality parameters such as chlorophyll-a (Chl-a). However, the use of RS techni...

In biogeography it is well established that environmental variables often have scale-dependent effects on abundance and distribution of organisms. Here we present results from a study on scale-dependency of macrophyte (aquatic plant) richness to hydrology and land use indicators. Hydrological connectivity and land use within the landscape surroundi...

Cs-137 is considered to be the most significant anthropogenic contributor to human dose and presents a particularly difficult remediation challenge after a dispersal following nuclear incident. The Chernobyl Nuclear Power Plant meltdown in April 1986 represents the largest nuclear accident in history and released over 80 PBq of 137Cs into the envir...

Water and sediment load of rivers varies at different time scales: short term variations are related to catchment influences (e.g. floods variability), long term variations are related to river human activities (decennial to secular time scale) and climate variability (Pont et al., 2002). These changes impact the dynamic of river-sea transitional e...

The Chernobyl nuclear power plant meltdown has to date been the single largest release of radioactivity into the environment. As a result, radioactive contamination that poses a significant threat to human health still persists across much of Europe with the highest concentrations associated with Belarus, Ukraine, and western Russia. Of the radionu...

Research at the interface between terrestrial, riverine, estuarine and marine environments is frequently constrained by significant disciplinary and geographical boundaries. This article outlines an international initiative, DANUBIUS-RI, which aims to address these problems by facilitating biogeochemical monitoring and interdisciplinary research on...

Inland and coastal waterbodies are critical components of the global biosphere. Timely monitoring is necessary to enhance our understanding of their functions, the drivers impacting on these functions and to deliver more effective management. The ability to observe waterbodies from space has led to Earth observation (EO) becoming established as an...

The H2020 project EOMORES will develop operational monitoring and reporting services for inland and coastal water quality based on a combination of the most up-to-date satellite data, innovative in situ instruments and ecological models. Lakes, reservoirs and coastal water bodies constitute essential components of the hydrological and biogeochemica...

The development and validation of remote-sensing-based approaches for the retrieval of chromophoric dissolved organic matter (CDOM) concentrations requires a comprehensive understanding of the sources and magnitude of variability in the optical properties of dissolved material within lakes. In this study, spatial and seasonal variability in concent...

Remote sensing has the potential to capture data on the presence, abundance, distribution, and phenology of cyanobacteria in inland, coastal, and open ocean waters at a range of spatial and temporal scales. Many different approaches to the detection of cyanobacterial blooms from airborne and spaceborne remote sensing have been developed including t...

Plants would the start with step of a metal's pathway starting with the dirt on heterotrophic creatures for example, such that animals and humans, thus the substance from claiming metallic follow components for eatable parts of a plant representable accessible load of these metals that might enter those natural way of life through plants. Around me...

Atmospheric correction of remotely sensed imagery of inland water bodies is essential to interpret water-leaving radiance signals and for the accurate retrieval of water quality variables. Atmospheric correction is particularly challenging over inhomogeneous water bodies surrounded by comparatively bright land surface. We present results of AisaFEN...

This report presents the results of the 2015 survey to determine the habits and consumption patterns of people living and undertaking recreational activities in the vicinity of the Babcock Rosyth Site (BRS). The site is authorised to discharge gaseous radioactive waste in addition to the discharge of liquid radioactive waste through an outfall into...

Conference Presentation

The development and validation of remote sensing-based approaches for the retrieval of CDOM concentrations requires a comprehensive understanding of the sources and magnitude of variability in the optical properties of dissolved material within lakes. In this study, spatial and seasonal variability in concentration and composition of CDOM and the o...

Chlorophylla is a green pigment, used as an indirect measure of lake water quality. Its strong absorption of blue and red light allows for quantification through satellite images, providing better spatial coverage than traditional in-lake samples. However, grid-cell scale imagery must be calibrated spatially using in-lake point samples, presenting...

PhD outline

Some physico-chemical properties and the concentrations of the metals Fe, Mn, Ni, Cd, Cr, Co, Cu, Pb and Zn in water and sediments were examined from September 2011 to January 2012 in Bodo Creek where oil spills have been recurrent. Temperature, pH, total dissolved solid, conductivity, salinity, dissolved oxygen, biological oxygen demand (BOD), che...

There are a large number of sites across the UK and the rest of the world that are known to be contaminated with (226)Ra owing to historical industrial and military activities. At some sites, where there is a realistic risk of contact with the general public there is a demand for proficient risk assessments to be undertaken. One of the governing fa...

The 10-year archive of MEdium Resolution Imaging Spectrometer (MERIS) data is an invaluable resource for studies on lake system dynamics at regional and global scales. MERIS data are no longer actively acquired but their capacity for global scale monitoring of lakes from satellites will soon be re-established through the forthcoming Sentinel-3 Ocea...

Background: It is suggested the declining male birth proportion in some industrialized countries is linked to ubiquitous endocrine disruptor exposure. Stress and advanced parental age are determinants which frequently present positive findings. Multi-factorial influences on population sex ratio are rarely explored or tested in research. Objective...

This paper presents results of applying new methods to improve understanding of disturbance to forest soil resulting from stump harvesting. For a number of countries there is interest in the application of stump harvesting as a source of forest fuel, but there is also a widely held concern about the soil disturbance that may result from it. In ass...

Radioactive 'hot particles' that occur in the environment present specific challenges for health and environmental regulators as often their small size makes them difficult to detect, and they are easily dispersed and accidentally ingested or inhaled by members of the public. This study of nine hot particles recovered from the beach at Dalgety Bay,...

The manufacture and use of radium in the early to mid-20th century within industrial, medicinal and recreational products have resulted in a large number of contaminated sites across a number of countries with notable examples in the USA and Europe. These sites, represent a significant number of unregulated sources of potential radiological exposur...

Regulatory authorities need ways to estimate natural terrestrial gamma radiation dose rates (nGy h(-1)) across the landscape accurately, to assess its potential deleterious health effects. The primary method for estimating outdoor dose rate is to use an in situ detector supported 1 m above the ground, but such measurements are costly and cannot cap...