Dr Peter D. Hunter

Lecturer in Environmental Remote Sensing

B.Sc. (Hons) – University of Stirling (1999-2003)
Ph.D. – University of Stirling (2003-2007)

Room 4B162, Cottrell Building

School of Biological and Environmental Sciences
University of Stirling, Stirling, Scotland, FK9 4LA

Tel.: +44 1786 467810 | Fax: +44 1786 467843 | Email: Peter Hunter

ResearcherID | academia.edu

I am an environmental scientist with interests in the application of remote sensing in both aquatic and terrestrial ecology.  Much of my research activity is currently focused on the development of remote sensing-based techniques for monitoring changes in the ecological status and functioning of lakes, rivers and wetlands and with particular reference to phytoplankton blooms, macrophytes, suspended sediment fluxes, and the effects of diffuse pollutants such as nutrients and heavy metals.  I also have interests in the use of remote sensing for mapping vegetation composition and condition in peatlands, floodplains and agricultural landscapes and for mapping the distribution of contaminants in the environment.

I am especially interested in the use of high spatial-resolution hyperspectral imaging, its fusion with laser altimetry and other remotely sensed data sources, and the application of different techniques for extracting ecological-relevant information from image data, such as radiative transfer modelling, statistical and numerical modelling, spectral unmixing, fuzzy and nonlinear classification (e.g., Support Vector Machines, Artificial Neural Networks).

Undergraduate

Postgraduate

ENV5A5

Environmental Policy and Management

ENMP04

Environmental Policy and Management

ENV5T5

Advanced Analytical Techniques

ENMP06

Catchment Management & Water Quality

ENV6DB

Drainage Basins

ENMP11

Remote Sensing for Environmental Managers (course co-ordinator)

ENV8RS

Remote Sensing

funded by the Carnegie Trust for the Universities of Scotland

Collaborators: Dr Neil Cowie (RSPB)

Peatlands only cover a small proportion of the earth’s surface, but are strongly coupled to its climate.  This is because they uptake and release the greenhouse gases that cause climate change.  Measuring the release of greenhouse gases from peatlands is important if we are to understanding the long-term implications for climate change.

The plants that grow on peatlands strongly influence the exchange of these gases between the soil and atmosphere, but it is extremely difficult to conduct plant surveys over large expanses of peatland.  This project is investigating the potential of airborne and satellite remote sensing for mapping peatland vegetation and condition in the Flow Country, Caithness.

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supported by NERC ARSF and NERC FSF

Collaborators: Dr Andrew Tyler (Stirling), Steve Groom (PML), Dr Mátyás Présing (BLRI), Dr Attila Kovács (BLRI) and András Zlinszky (BLRI).

Cyanobacteria are ancient and cosmopolitan inhabitants of fresh, brackish and marine waters and play a central role in biogeochemical cycling, particularly carbon and nitrogen fixation.  However, in nutrient-enriched waters, toxin-producing cyanobacteria often form mass nuisance populations.  These mass populations are a serious concern for the ecological status of lakes and pose significant risks to animal and human health. 

The aim of this project is to obtain an improved understanding of the bio-optical properties of inland waters so that we can develop more effective inversion algorithms for the detection and near-real time mapping of cyanobacterial blooms at regional-to-global scales.  This work will be undertaken in Lake Balaton in 2010.

funded by the NERC Environment and Human Health programme

Collaborators: Dr Andrew Tyler (Stirling) (PI), Dr Laurence Carvalho (CEH), Professor Geoffrey Codd  (Dundee) and Dr Stephen Maberly (CEH)

Cyanobacteria are natural inhabitants of fresh-, brackish- and marine waters.  They represent a key component of the microbial biodiversity of aquatic ecosystems and play an important role in biogeochemical cycling. However, the development of mass populations of cyanobacteria in nutrient-enriched waters, either as blooms, scums or biofilms, can pose significant risks to animal and human health because of their capacity to produce numerous potent toxins (e.g. microcystin, anatoxin, cylindrospermopsin).  These toxins constitute some of the most hazardous of all biological substances found in natural waters.  The need for improved monitoring and management of cyanobacterial blooms in inland waters has thus been recognised by a number of national (e.g. EA, SEPA) and international bodies (e.g. WHO, UNESCO).

In this project we are developing remote sensing-based techniques for mapping the distribution of potentially toxic cyanobacteria at spatially synoptic scales using hyperspectral AISA Eagle and Hawk imagery acquired by the NERC Airborne Research and Survey Facility (right).  Various semi-empirical and semi-analytical inversion algorithms are being tested for the retrieval of chlorophyll a and the cyanobacterial biomarker pigment C-phycocyanin.  The retrieved pigment concentrations are then being related to cyanobacterial cell numbers and toxin concentrations so that we can evaluate the potential of remote sensing to provide information to support risk assessment activities for the protection of animal and human health.

funded by the Conseil Scientifique de l'ENS LSH

Collaborators: Professor Hervé Piégay (ENS LSH) (PI) and Dr Simon Dufour (CEREGE, Université de Provence)

Temperate riparian forests are biologically diverse, but have become increasingly rare throughout central and western Europe.  Dam construction in the upper watersheds of many gravel-bed rivers has significantly reduced stream flows and lowered water tables.  This can greatly impact pioneer tree species (e.g., ash (Fraxinous L.) and alder (Alnus L.)) that grow optimally on wet and deep alluvial (or colluvial) deposits and whose rejuvenation depends on regular disturbance by flood inundation.  The construction of the Vouglans Dam (ca. 1968) in the upper watershed of the River Aîn (France) has significantly affected stream flows and water table levels in the lower parts of the catchment.  This has resulted in a loss of hydrological connectivity between the channel and the wider floodplain and significant impacted riparian forest growth and rejuvenation.

Satellite imagery can be used to assess forest growth and stress at the landscape scale.  Importantly, this approach can be used to gain insights into forest dynamics that are not easily observed from ground-based, plot-scale, measurements.  In this study, we are constructing a time-series of the normalised difference vegetation index (NDVI) data using multi-decadal Landsat MSS/TM and high-resolution Quickbird data to explore longitudinal variation in the growth of ash-alder forest in relation to channel degradation on the floodplain of the River Aîn.  We are using high-resolution LiDAR imagery to measure longitudinal variations in the elevation of the floodplain relative to the contemporary water table as a means of determining the hydrological connectivity of different forest units.

funded by Scottish Water

Collaborators: Dr Nigel Willby (Stirling) (PI)

Natural and constructed wetlands are now recognised as an important method of managing stormwater runoff in urban environments and immobilising and extracting potentially-toxic contaminants from soils, sediments and surface waters.  These urban ponds and wetlands typically receive a range of anthropogenically-derived contaminants in the runoff from roads, car parks, sewage treatments works, industrial facilities and residential developments.  Mineral nutrients and heavy metals are readily sequestered by some wetland plants species and this has led to the increasingly widespread use of wetland plants for the phytoremediation of contaminated urban waters.

However, these contaminants may also pose problems for the sustainability of plant growth in urban wetlands when received in very high concentrations.  In this project, we are investigating the utility of remote sensing as a tool for the early-detection and measurement of plant stress in variously contaminated urban wetlands.  Hyperspectral reflectance measurements from plant canopies and apical leaves have been used to calculate a number of spectral indices that can be related to plant health.  These indices can then be related to varaibility in contaminant loadings as a means of identifying what factors might limit plant growth and recruitment in the future.

co-funded by the University of Stirling and Northumbrian Water

Collaborators: Dr Andrew Tyler (Stirling), Dr Nigel Willby (Stirling), Professor David Gilvear (Stirling), Dr Mátyás Présing (BLRI), Dr Attila Kovács (BLRI) and Andrea Kelly (Broads Authority)

Shallow lakes are an important ecological and socio-economic resource.  However, the impact of human pressures, both at the lake and catchment scale, has precipitated a decline in the ecological status of many shallow lakes, both in the UK, and throughout Europe.  There is now, as direct consequence, unprecedented interest in the assessment and monitoring of ecological status and trajectory in shallow lakes, not least, in response to the European Union Water Framework Directive (2000/60/EC) and Habitats Directive (92/43/EEC).

In this context, the spatially-resolving and panoramic data provided by remote sensing platforms may be of immense value in the construction of effective and efficient strategies for the assessment and monitoring of ecological status in shallow lakes and, moreover, in providing new, spatially-explicit, insights into the function of these ecosystems and how they responsed to change.  This project examined the use of remote sensing data for the assessment of (i) phytoplankton and (ii) aquatic vegetation in shallow lakes with a view to establishing the merits of such approaches for use in limnological research and monitoring.

Hunter, P.D., Hanley, N.D., Czajkowski, M., Mearns, K., Tyler, A.N., Carvalho L. and Codd, G.A. (in prep.) The effect of risk perception on public preferences and willingness-to-pay for reductions in the health risks posed by toxic cyanobacteria blooms. Science of the Total Environment.

Hunter P.D. and Piégay H. (in prep.) Classification of floodplain forest habitat using pixel-level fusion of Quickbird and LiDAR imagery. International Journal of Remote Sensing.

Gilvear, D.G., Hunter, P.D., Milner, T. and Bowes, J. (in prep.) Modelling as a tool for assessing medium-term (<100 years) changes in gravel dependent habitats within managed rivers: River Tay Scotland. River Research and Applications.

Hunter, P.D. and Tyler, A.N. (in prep.) Using derivative analysis to retrieve phycocyanin concentrations in shallow lakes.  Remote Sensing Letters.

Hunter, P.D., Tyler, A.N., Carvalho, L., Codd, G.A. and Maberly, S.C. (in review) Hyperspectral remote sensing of cyanobacterial pigments as indicators for cell populations and toxins in eutrophic lakes. Remote Sensing of Environment.

Hunter, P.D., Willby, N.J., Tyler A.N., Gilvear D.J. and Kelly A. (in review) Mapping aquatic vegetation in shallow lakes using imagery from the compact airborne spectrographic imager (CASI-2). Aquatic Conservation: Marine and Freshwater Ecosystems.

Elmetwalli A.M.H., Tyler, A.N., Hunter P.D. and Salt, C.A. (in review). Detecting and distinguishing moisture and salinity induced stress in wheat and maize through in situ spectroradiometry measurements. Remote Sensing Letters.

Elmetwalli, A.M.H., Tyler, A.N., Hunter P.D. and Salt, C.A. (in review) The potential of remotely sensed data to predict wheat and maize grain yield under moisture and salinity stress. Journal of Agronomy.

Lejot J., Piégay H., Hunter P.D., Gagnage M. and Moulin B. (in review) Utilisation de la télédétection pour la caractérisation physique des cours d’eau : exemples d’application et enjeux actuels. La Houille Blanche.

Hunter, P.D. and Willby, N.J. (in review) Diagnosing the causes of plant stress in urban wetlands using spectral reflectance indices. Remote Sensing of Environment.

Tyler, A.N., Hunter, P.D., Carvalho, L., Codd, G.A., Elliot, J.A., Ferguson, C.A., Hanley, N.D., Hopkins, D.W., Maberly, S.C., Mearns, K.J. and Scott, E.M. (2009) Strategies for monitoring and managing mass populations of toxic cyanobacteria in recreational waters: a multi-interdisciplinary approach. Environmental Health, 8 (Suppl 1):S11.

Hunter, P.D., Tyler, A.N., Gilvear, D.J. and Willby, N.J. (2009) Using remote sensing to aid the assessment of human health risks from blooms of potentially-toxic cyanobacteria. Environmental Science and Technology, 43 (7), pp. 2627-2633.

Hunter, P.D., Tyler, A.N., Gilvear, D.J. and Willby, N.J. (2008) The spatial dynamics of vertical migration by Microcystis aeruginosa in a eutrophic shallow lake: A case-study using high spatial resolution time-series airborne remote sensing. Limnology and Oceanography, 53 (6), pp. 2391-2406.

Hunter, P.D., Tyler., A.N., Presing, M., Kovacs, A. and Preston, T. (2008) Spectral discrimination of phytoplankton colour groups: The effect of suspended particulate matter and sensor spectral resolution. Remote Sensing of Environment, 112 (4), pp. 1527-1544.

Boruah, S., Gilvear D.J., Hunter P.D. and Sharma, N. (2008) A feasibility study assessing the value of satellite data for physical habitat mapping on the Brahmaputra River, India. River Research and Applications, 24, pp. 47-67.

Gilvear, D.G., Hunter, P.D. and Higgins, T.J. (2007) An experimental approach to the measurement of the effects of water depth and substrate on optical and near infra-red reflectance: a field-based assessment of the feasibility of mapping submerged in-stream habitat. International Journal of Remote Sensing, 28 (10), pp. 2241-2256

The Royal Scottish Geographical Society

The British Phycological Society