John Icely
University of the Algarve
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Featured researches published by John Icely.
Ecology and Society | 2014
Sergio Cinnirella; Rafael Sardá; Juan Luis Suárez de Vivero; Ruth Brennan; Alberto Barausse; John Icely; Tiziana Luisetti; David March; Carla Murciano; Alice Newton; Tim O'Higgins; Luca Palmeri; Maria Giovanna Palmieri; Pascal Raux; Sian Rees; J. Albaigés; Nicola Pirrone; Kerry Turner
The Mediterranean region is of fundamental importance to Europe given its strategic position. The responsibility for its overall ecosystem integrity is shared by European Union Member States (EU-MS) and other Mediterranean countries. A juxtaposition of overlapping governance instruments occurred recently in the region, with the implementation of both the Marine Strategy Framework Directive (MSFD) for EU-MS and the Ecosystem Approach Strategy (ECAP) for all Mediterranean countries, including EU-MS. Both MSFD and ECAP are structured around vision-driven processes to achieve Good Environmental Status and a Healthy Environment, respectively. These processes have clear ecosystem-based, integrated policy objectives to guarantee the preservation and integrity of Mediterranean marine ecosystem goods and services. However, adoption of these instruments, especially those related to the new EUMS directives on marine policy, could result in a governance gap in addition to the well-known economic gap between the EU and the non-EU political blocs. We identify two complementary requirements for effective implementation of both MSFD and ECAP that could work together to reduce this gap, to ensure a better alignment between MSFD and ECAP and better planning for stakeholder engagement. These are key issues for the future success of these instruments in a Mediterranean region where discrepancies between societal and ecological objectives may pose a challenge to these processes.
Hydrobiologia | 2013
Karsten Dromph; Susana Agustí; Alberto Basset; Javier Franco; Peter Henriksen; John Icely; Sirpa Lehtinen; Snejana Moncheva; Marta Revilla; Leonilde Roselli; Kai Sørensen
Characterisation of phytoplankton communities is important for classification of the ecological status of marine waters. In order to design a monitoring programme, it is important to know what degree of variation in the measurements occur at each level (water body, station and sample), so that resources can be spent in a way that maximise the precision of the measured parameters. Seven European water bodies were sampled to assess the variation in pigment concentrations and population densities attributed to water body, station and sample levels. It was found that the main proportion of the variation between pigment measurements was explained by the variation between stations (12–91% of variation) followed by the variation between water bodies (0–89% of variation). For measurements of population density, the main proportion of the variation between densities of cells recorded was explained by the variation between the taxonomists counting the samples (61%), whilst the main proportion of the variation between numbers of taxa recorded was explained by the variation between water bodies (83%). When the cell density of the nine dominant classes were analysed separately, the main proportion of variation was explained at the water body level for all but two class.
Journal of remote sensing | 2014
Sónia Cristina; Gerald Moore; Priscila Goela; John Icely; Alice Newton
Water-leaving reflectance (ρw) data from the European Space Agency ocean colour sensor Medium Resolution Imaging Spectrometer (MERIS) was validated with in situ ρw between October 2008 and November 2011, off Sagres on the southwest coast of the Iberian Peninsula. The study area is exceptional, since Stations A, B, and C at 2, 10, and 18 km offshore are in optically deep waters at approximately 40, 100, and 160 m, respectively. These stations showed consistently similar bio-optical properties, characteristic of Case 1 waters, enabling the evaluation of adjacency effects independent of the usual co-varying inputs of coastal waters. Using the third reprocessing of MERIS with the standard MEGS 8.1 processor, four different combinations of procedures were tested to improve the calibration between MERIS products and in situ data. These combinations included no vicarious adjustment (NoVIC), vicarious adjustment (VIC), and, for mitigating the effects of land adjacency on MERIS ρw, the improved contrast between ocean and land (ICOL) processor (version 2.7.4) and VIC + ICOL. Out of approximately 130 potential matchups for each station, 38–77%, 74–86%, and 88–90% were achieved at Stations A, B, and C, respectively, depending on which of the four combinations were used. Analyses of ρw comparing these various procedures, including statistics, scatter plots, histograms, and MERIS full-resolution images, showed that the VIC procedure compared with NoVIC produced minimal changes to the calibration. For example, at the oceanic Station C, the regression slope was closer to unity at all wavelengths with NoVIC compared to VIC, whereas, with the exception of wavelengths 412 and 443 nm, the intercept, mean ratio (MR), absolute percentage difference (APD), and relative percentage difference (RPD) were better with NoVIC. The differences for MR and APD indicate that there was marginal improvement for these two bands with VIC, and an over-adjustment with RPD. ICOL also showed inconsistent results for improving the retrieval of the near-shore conditions, but under some conditions, such as ρw at wavelength 560 nm, the improvement was striking. VIC + ICOL showed results intermediate between those of VIC and ICOL implemented separately. In relation to other validation sites, the offshore Station C at Sagres had much in common with the Mediterranean deep water, BOUSSOLE buoy, although the matchup statistics between MERIS ρw and in situ ρw were much better for Sagres than for BOUSSOLE. Strikingly, the matchup statistics for ρw at Sagres were very similar to those for the Acqua Alta Oceanographic Tower (AAOT), where the AAOT showed more scatter at 412 nm, probably because of the atmospheric correction where the aerosol optical thickness is higher at the AAOT. Conversely, Sagres showed much greater scatter at 665 nm in the red as the values were generally close to the limits of detection owing to the clearer waters at Sagres compared to the more turbid waters at the AAOT.
IEEE Geoscience and Remote Sensing Letters | 2016
Sónia Cristina; Davide D'Alimonte; Priscila Goela; Tamito Kajiyama; John Icely; Gerald Moore; Bruno Fragoso; Alice Newton
This study investigates standard and regional algal pigment index! (API!) estimates in the Atlantic off the southwestern Iberian Peninsula. Standard API! data are those delivered by the Medium Resolution Imaging Spectrometer (MERIS) orbiting sensor. Equivalent quantities are computed by applying a regional inversion scheme using as input both MERIS and in situ remote sensing reflectances (Rrs). Reference data for the development of the regional algorithm and for the analysis of tested products include field measurements of total concentration of chlorophyll a (TChla) and coincident Rrs values collected at different distances from the coast. Validation results, based on matchup analysis, identifies a systematic overestimation of standard API1 versus the reference TChla values. The additional comparison of product maps in selected regions of interest confirms this tendency and demonstrates the feasibility and relevance of using regional algorithms for investigating spaceborne products. Analogous applications are hence devised for the early-stage evaluation of the forthcoming Sentinel-3/OLCI data products.
Environmental Forensics | 2007
M. Glória Pereira; John Icely; Stephen M. Mudge; Alice Newton; Rubina M. N. V. Rodrigues
The spatial and temporal variation of phytoplankton pigments in the western part of Ria Formosa, Portugal, was investigated between September 2000 and July 2002. Sampling stations included the ocean boundary (Ancão inlet) and two different landward boundary situations: 1) the shallow westernmost “blind end” of the lagoon (Ponte) and 2) near a main sewage outlet (Ramalhete). Nutrient concentrations were higher during the first year of sampling but were lower than those recorded in previous studies. This decrease in the concentration of nutrients was possibly the result of the 1997 relocation of the Ancão inlet, which allowed better water circulation in the lagoon. Throughout this study, concentrations of chlorophyll a determined by high-performance liquid chromatography were consistently low. Inter-annual variability in the pattern of chlorophyll a concentration was observed in the form of a bimodal peak (spring/summer and autumn) between September 2000 and June 2001 and more uniform concentrations from September 2001 until July 2002. Principal component analysis of the concentrations of all pigments did not indicate any spatial- or tidal-related variations but did show that pigment concentrations varied over time. Partial least squares analysis corroborated this temporal shift of the phytoplankton pigment abundance and composition and showed that these shifts could be linked to certain environmental variables. Fucoxanthin was the dominant accessory pigment and was strongly correlated with chlorophyll a. Other marker pigments present in lower concentrations included chlorophyll b, 19′-hexanoyloxyfucoxanthin, neoxanthin, alloxanthin, diadinoxanthin, lutein, zeaxanthin, and beta-carotene. PLS analysis was used to infer the dominant phytoplanktonic groups in the lagoon. This analysis established that diatoms and other algal groups with a similar pigment profile dominated the phytoplankton community throughout the year. Cryptophytes were the second most abundant group in the lagoon. The remaining groups, including dinoflagellates, cyanophytes, and chlorophytes, contributed much less to the total algal biomass (generally < 10%).
Environmental Forensics | 2008
D. Wayland; David Megson; Stephen M. Mudge; John Icely; Alice Newton
Nutrient concentrations within watercourses are often associated with the input of sewage or the runoff of fertilizers. Due to population increases, there has been a dramatic rise in the amount of fertilizer applied to land, as well as in the further development of sewage treatment plants (STPs), both of which can lead to significant discharges with associated eutrophication risks in coastal waters. The implementation of the European Union Water Framework Directive (EU-WFD) should improve the management and quality of European water bodies. The Ria Formosa Lagoon, Portugal, is one such water body monitored under the WFD where two inter-calibration sites have been developed, that of the Ancão Basin, which has a status of “high/good,” and that of the Ramalhete Channel, with a status of “good/moderate.” Spatial nutrient concentrations (NH4 +, NO2 –, NO3 –, PO4 3–) and lipids were measured in two areas that were thought to contribute nutrients into the Ancão Basin; a river that flows through several golf courses and the Ramalhete Channel, which receives discharge from both Faro Airport and a STP. Nutrient analyses showed that waters from the Ramalhete Channel had substantial concentrations, the highest of which was ammonium, which exceeded 180 μ M near the sewage discharge site; however, concentrations diminished towards the sea, reaching 2.7 μ M suggesting the utilization of NH4 + by seagrasses (Zostera noltii). The Atlantic Ocean was also a source of nitrate, contributing 1.8 μ M, whereas sources of phosphate originated in the Ancão Basin catchment and included a commercial horticulture site, several golf courses, and the STP. Principal component analysis (PCA) and cross plots of the 5β-coprostanol/cholesterol and 5β-coprostanol/(5β-coprostanol + 5α-cholestanol) ratios identified areas of fecal contamination, highlighting several sites previously unknown to contain sewage matter. In general, nitrogen sources were associated with agriculture and phosphate originated from the golf complex and sewage discharges. These effects were partly mitigated, however, by eutrophic ponds between the river and the lagoon.
Journal of Natural History | 1983
D.A. Jones; John Icely; Simon M. Cragg
Summary The corallanid isopods, C. nodosa, C. estuaria sp. nov. C. bidentata sp. nov. and C. tridentata sp. nov. have been found within timbers of mangroves and man-made structures in marine and brackish waters around Papua New Guinea. Corallana estuaria, C. bidentata and C. tridentata are new to science and are described in detail. In addition, aspects of the ecology of all four species are considered, including their association with the marine-boring isopods, Sphaeroma terebrans and S. triste.
Environmental Technology | 1998
Stephen M. Mudge; L. Hooper; John Icely
A study of the biomarkers associated with human sewage was conducted on the Arade Estuary and its tributaries, the R. de Boina and Odelouca, Southern Portugal. Surface sediment samples were collected at 20 sites in the system and analysed by gas chromatography - mass spectrometry (GC-MS) for sterols and fatty alcohols. The coprostanol/cholesterol ratio indicated substantial sewage contamination in the Boina and in the lower reaches of the Arade Estuary. The lack of epi-coprostanol suggested that this material was essentially untreated. Other sterols (β-sitosterol and brassicasterol) indicate phytoplankton biomass in the middle and upper reaches of the estuary. The fatty alcohols were not correlated with the β-sitosterol, unlike the brassicasterol, and therefore suggest an algal origin for this matter. Organic matter derived from vascular plants (high C22/C16 ratio) was limited to the central portion of the Estuary where a marsh-like community has developed.
Water science | 2018
Sirak Robele Gari; Cesar Enrique Ortiz Guerrero; Bryann A-Uribe; John Icely; Alice Newton
Abstract A portion of Colombia’s water resources is located on the Pacific coast within the territory of the Community Council of Alto and Medio Dagua (CC-AMDA). Though a harmonious balance between the communities’ subsistent activities and nature was maintained for centuries, the appearance of modern modes of resource extraction has negatively affected the environment, especially the water resources. The Driver-Pressure-State- Impact-Response (DPSIR) framework was used to analyze water quality problems within this community council. The DPSIR analysis revealed that agriculture, mining, logging and infrastructure development constitute important sectoral drivers with some contribution from tourism and fisheries. Pressures included inputs of organic matter, sediment, nutrients and chemical contaminants to the Dagua river, and to the Bay of Buenaventura. These produced corresponding State changes in the water bodies. Impacts on human welfare were poor public health, reduced food and water security, economic loss and some displacement. Societal Responses included public protests and campaigns, legal actions and policy changes for improved governance. As a future policy option, the formation of community-based water resources management is recommended. Though DPSIR was able to link cause-effect relations, further empirical research on these water bodies is necessary to fill in existing gaps in the data set, particularly for public health threatening contaminants.
Continental Shelf Research | 2003
Alice Newton; John Icely; Manuela Falcão; A. Nobre; J. Nunes; Júlia R. Ferreira; Carlos Vale