Integration of Radiometric Ground-Based Data and High-Resolution QuickBird Imagery with Multivariate Modeling to Estimate Maize Traits in the Nile Delta of Egypt.

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 radiometric ground-based data and high-resolution QuickBird satellite imagery to determine the leaf area index (LAI), biomass fresh weight (BFW) and chlorophyll meter (Chlm) of maize across well-irrigated, water stress and salinity stress areas in the Nile Delta of Egypt. Partial least squares regression (PLSR) and multiple linear regression (MLR) were evaluated to estimate the three measured traits based on vegetation spectral indices (vegetation-SRIs) derived from these methods and their combination. Maize field visits were conducted during the summer seasons from 28 to 30 July 2007 to collect ground reference data concurrent with the acquisition of radiometric ground-based measurements and QuickBird satellite imagery. The results showed that the majority of vegetation-SRIs extracted from radiometric ground-based data and high-resolution satellite images were more effective in estimating LAI, BFW, and Chlm. In general, the vegetation-SRIs of radiometric ground-based data showed higher R2 with measured traits compared to the vegetation-SRIs extracted from high-resolution satellite imagery. The coefficient of determination (R2) of the significant relationships between vegetation-SRIs of both methods and three measured traits varied from 0.64 to 0.89. For example, with QuickBird high-resolution satellite images, the relationships of the green normalized difference vegetation index (GNDVI) with LAI and BFW showed the highest R2 of 0.80 and 0.84, respectively. Overall, the ground-based vegetation-SRIs and the satellite-based indices were found to be in good agreement to assess the measured traits of maize. Both the calibration (Cal.) and validation (Val.) models of PLSR and MLR showed the highest performance in predicting the three measured traits based on the combination of vegetation-SRIs from radiometric ground-based data and high-resolution QuickBird satellite imagery. For example, validation (Val.) models of PLSR and MLR showed the highest performance in predicting the measured traits based on the combination of vegetation-SRIs from radiometric ground-based data and high-resolution QuickBird satellite imagery with R2 (0.91) of both methods for LAI, R2 (0.91-0.93) for BFW respectively, and R2 (0.82) of both methods for Chlm. The models of PLSR and MLR showed approximately the same performance in predicting the three measured traits and no clear difference was found between them and their combinations. In conclusion, the results obtained from this study showed that radiometric ground-based measurements and high spectral resolution remote-sensing imagery have the potential to offer necessary crop monitoring information across well-irrigated, water stress and salinity stress in regions suffering lack of freshwater resources.

Multi-factorial influences on sex ratio: a spatio-temporal investigation of endocrine disruptor pollution and neighborhood stress.

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. OBJECTIVES: To test the hypothesis that dual factors of pollution and population stress affects sex proportion at birth through geographical analysis of Central Scotland. METHODS: The study incorporates the use of Geographical Information Systems (GIS) tools to overlay modeled point source endocrine disruptor air emissions with "small-area" data on multiple deprivation (a proxy measurement of stress) and birth sex. Historical review of regional sex ratio trends presents additional data on sex ratio in Scotland to consider. RESULTS: There was no overall concentration in Central Scotland of low sex ratio neighborhoods with areas where endocrine disruptor air pollution and deprivation or economic stress were high. Historical regional trends in Scotland (from 1973), however, do show significantly lower sex ratio values for populations where industrial air pollution is highest (i.e. Eastern Central Scotland). CONCLUSIONS: Use of small area data sets and pollution inventories is a potential new method of inquiry for reproductive environmental and health protection monitoring and has produced interesting findings.

Substantial increase of organic carbon storage in Chinese lakes.

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 during 1984-2023. Here we show that dissolved OC concentration is high in northwest saline lakes and particulate OC concentration is high in southeast eutrophic lakes. Along with increasing OC concentration and water volume, dissolved and particulate OC storage increase by 44.6% and 33.5%, respectively. Intensified human activities, water input, and wind disturbance are the key drivers for increasing OC storage. Moreover, higher OC storage further leads to an 11.0% increase in nationwide OC burial and a decrease in carbon emissions from 71.1% of northwest lakes. Similar changes are occurring globally, which suggests that lakes are playing an increasingly important role in carbon sequestration.

Global lake thermal regions shift under climate change.

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 identified that mapped robustly and largely contiguously globally, even for small lakes. The regions differed from other global patterns, and so provide unique information. Using a lake model forced by 21st century climate projections, we found that 12%, 27% and 66% of lakes will change to a lower latitude thermal region by 2080-2099 for low, medium and high greenhouse gas concentration trajectories (Representative Concentration Pathways 2.6, 6.0 and 8.5) respectively. Under the worst-case scenario, a 79% reduction in the number of lakes in the northernmost thermal region is projected. This thermal region framework can facilitate the global scaling of lake-research.

Strategies for monitoring and managing mass populations of toxic cyanobacteria in recreational waters: a multi-interdisciplinary approach.

Mass populations of toxin-producing cyanobacteria commonly develop in fresh-, brackish- and marine waters and effective strategies for monitoring and managing cyanobacterial health risks are required to safeguard animal and human health. A multi-interdisciplinary study, including two UK freshwaters with a history of toxic cyanobacterial blooms, was undertaken to explore different approaches for the identification, monitoring and management of potentially-toxic cyanobacteria and their associated risks. The results demonstrate that (i) cyanobacterial bloom occurrence can be predicted at a local- and national-scale using process-based and statistical models; (ii) cyanobacterial concentration and distribution in waterbodies can be monitored using remote sensing, but minimum detection limits need to be evaluated; (iii) cyanotoxins may be transferred to spray-irrigated root crops; and (iv) attitudes and perceptions towards risks influence the public's preferences and willingness-to-pay for cyanobacterial health risk reductions in recreational waters.

Identification of a novel glucosylsulfate conjugate as a metabolite of 3,4-dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5,6-dione (ARQ 501, beta-lapachone) in mammals.

3,4-Dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5,6-dione (ARQ 501) is a fully synthetic version of the natural product beta-lapachone, which has been isolated from the lapacho tree (Tabebuia impetiginosa or Tabebuia avellanedae) and has demonstrated promising anticancer activity. ARQ 501 formulated with hydroxypropyl-beta-cyclodextrin has successfully completed phase I clinical trials and is currently in several phase II human clinical trials for the treatment of pancreatic cancer, head and neck cancer, and leiomyosarcoma. The metabolites of ARQ 501 were investigated by low-resolution and high-resolution mass spectrometry in plasma from (nu/nu) mice, rats, and humans treated with the compound. The data for one of the metabolites identified are consistent with conjugation of ARQ 501 with a glucosylsulfate moiety (m/z 241; fragment ion). Although other glucosylsulfate conjugates have been identified as metabolites of pesticides in cotton plants and in crustaceans as phase II metabolites of pyrenes, none have been previously identified in mammals. Data reported here identify a novel metabolic pathway for humans.

Preliminary results from the first national in situ gamma spectrometry survey of the United Kingdom.

In situ gamma spectrometry was introduced as part of a national soil and herbage pollution survey of the United Kingdom (UK) in 2002, to evaluate its potential for complimenting or even replacing the conventional soil sampling approach in environmental monitoring. A total of 128 points were measured across the whole of the UK on a 50-km grid, including 11 calibration sites, encompassing a complete spectrum of soil types, geology and depositional environments. Good comparisons are demonstrated between in situ and soil sample derived estimates of environmental radioactivity from spatially matched sampling plans. Air kerma results and the contributions to air kerma rate are also presented and compared with calibrated conventional single parameter GM based instruments. The preliminary results are presented here and show that in situ gamma spectrometry provides a rapid and robust approach, providing spatially integrated estimates for environmental monitoring purposes.

Developments in Earth observation for the assessment and monitoring of inland, transitional, coastal and shelf-sea waters.

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 physical, chemical and biological processes in surface waters poses significant challenges for in situ monitoring and assessment and often limits our ability to adequately capture the dynamics of aquatic systems and our understanding of their status, functioning and response to pressures. Here we explore the opportunities that Earth observation (EO) has to offer to basin-scale monitoring of water quality over the surface water continuum comprising inland, transition and coastal water bodies, with a particular focus on the Danube and Black Sea region. This review summarises the technological advances in EO and the opportunities that the next generation satellites offer for water quality monitoring. We provide an overview of algorithms for the retrieval of water quality parameters and demonstrate how such models have been used for the assessment and monitoring of inland, transitional, coastal and shelf-sea systems. Further, we argue that very few studies have investigated the connectivity between these systems especially in large river-sea systems such as the Danube-Black Sea. Subsequently, we describe current capability in operational processing of archive and near real-time satellite data. We conclude that while the operational use of satellites for the assessment and monitoring of surface waters is still developing for inland and coastal waters and more work is required on the development and validation of remote sensing algorithms for these optically complex waters, the potential that these data streams offer for developing an improved, potentially paradigm-shifting understanding of physical and biogeochemical processes across large scale river-sea systems including the Danube-Black Sea is considerable.

Assessment of physico-chemical properties and metal contents of water and sediments of Bodo Creek, Niger Delta, Nigeria.

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), chemical oxygen demand (COD), total hardness, sulfate, nitrate, and phosphate were determined in surface water. Particle size, total organic matter (TOM), and pH were also determined in the sediments. The parameters were within permissible limits except the mean values of BOD, COD, total hardness, and sulfate that exceeded levels permissible for domestic use. The sediments consisted mainly of sand, with TOM ranging from 0.2% to 5.5%. With the exception of cadmium that was below detection limit, metal levels (mg kg-1) in the sediments were 12 (Mn), 1070 (Fe), 10 (Cu), 10 (Zn), 5.3 (Cr), 1.1 (Pb), 1.0 (Ni), and 0.5 (Co) while in water they were 24, 98, 21, 6.9, 4.0, 0.6, 0.18, and 0.16, respectively. The latter were higher than World Health Organization recommended permissible levels for both surface and drinking water.

High accuracy in situ radiometric mapping.

In situ and airborne gamma ray spectrometry have been shown to provide rapid and spatially representative estimates of environmental radioactivity across a range of landscapes. However, one of the principal limitations of this technique has been the influence of changes in the vertical distribution of the source (e.g. 137Cs) on the observed photon fluence resulting in a significant reduction in the accuracy of the in situ activity measurement. A flexible approach for single gamma photon emitting radionuclides is presented, which relies on the quantification of forward scattering (or valley region between the full energy peak and Compton edge) within the gamma ray spectrum to compensate for changes in the 137Cs vertical activity distribution. This novel in situ method lends itself to the mapping of activity concentrations in environments that exhibit systematic changes in the vertical activity distribution. The robustness of this approach has been demonstrated in a salt marsh environment on the Solway coast, SW Scotland, with both a 7.6 cm x 7.6 cm NaI(Tl) detector and a 35% n-type HPGe detector. Application to ploughed field environments has also been demonstrated using HPGe detector, including its application to the estimation of field moist bulk density and soil erosion measurement. Ongoing research work is also outlined.

Characterising the morphological properties and surface composition of radium contaminated particles: a means of interpreting origin and deposition.

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, UK, uses a combination of gamma spectrometry, imaging microscopy and SEM-EDX in order to characterise their morphology and surface composition, thereby helping to identify their origin and source characteristics. The nine particles analysed showed great heterogeneity in their activities, physical form and elemental composition. The particle activities were dominated by (226)Ra and its daughters. Three distinct grouping of particles were identified based on their morphology (artefact, glassy and 'metal-rich'), whilst four distinct groupings (artefact, glassy, angular and porphyric, rounded and highly porous) were identified based on morphology and surface properties as seen in the SEM. Whilst the 'artefact' particles were little altered, the other particles showed evidence of incineration. All particles were in a size and/or shape class vulnerable to wind- or water-mediated transport. No correlations were found between morphology and chemical composition. SEM-EDX analysis revealed C, Si, Zn, Fe, Ca are common in the particles together with Ba, Ni, Pb, Cu, Mn and Ti. This is interpreted as the particles being derived from radium containing luminescent paint containing a Zn/S phosphor, a hydrocarbon base and other fillers and additives. Evidence of copper and steel alloys were also present in some particles, whilst one consisted of a hydrocarbon based 'capsule'. The combination of techniques employed here has enabled interpretation of the origins of the radioactive particles and given insights into the potential movement of particles within the local environment.

The effect of risk perception on public preferences and willingness to pay for reductions in the health risks posed by toxic cyanobacterial blooms.

Mass populations of toxin-producing cyanobacteria are an increasingly common occurrence in inland and coastal waters used for recreational purposes. These mass populations pose serious risks to human and animal health and impose potentially significant economic costs on society. In this study, we used contingent valuation (CV) methods to elicit public willingness to pay (WTP) for reductions in the morbidity risks posed by blooms of toxin-producing cyanobacteria in Loch Leven, Scotland. We found that 55% of respondents (68% excluding protest voters) were willing to pay for a reduction in the number of days per year (from 90, to either 45 or 0 days) that cyanobacteria pose a risk to human health at Loch Leven. The mean WTP for a risk reduction was UK£9.99-12.23/household/year estimated using a logistic spike model. In addition, using the spike model and a simultaneous equations model to control for endogeneity bias, we found the respondents' WTP was strongly dependent on socio-demographic characteristics, economic status and usage of the waterbody, but also individual-specific attitudes and perceptions towards health risks. This study demonstrates that anticipated health risk reductions are an important nonmarket benefit of improving water quality in recreational waters and should be accounted for in future cost-benefit analyses such as those being undertaken under the auspices of the European Union's Water Framework Directive, but also that such values depend on subjective perceptions of water-related health risks and general attitudes towards the environment.

Cyanobacterial blooms: statistical models describing risk factors for national-scale lake assessment and lake management.

Cyanobacterial toxins constitute one of the most high risk categories of waterborne toxic biological substances. For this reason there is a clear need to know which freshwater environments are most susceptible to the development of large populations of cyanobacteria. Phytoplankton data from 134 UK lakes were used to develop a series of Generalised Additive Models and Generalised Additive Mixed Models to describe which kinds of lakes may be susceptible to cyanobacterial blooms using widely available explanatory variables. Models were developed for log cyanobacterial biovolume. Water colour and alkalinity are significant explanatory variables and retention time and TP borderline significant (R2-adj=21.9%). Surprisingly, the models developed reveal that nutrient concentrations are not the primary explanatory variable; water colour and alkalinity were more important. However, given suitable environments (low colour, neutral-alkaline waters), cyanobacteria do increase with both increasing retention time and increasing TP concentrations, supporting the observations that cyanobacteria are one of the most visible symptoms of eutrophication, particularly in warm, dry summers. The models can contribute to the assessment of risks to public health, at a regional to national level, helping target lake monitoring and management more cost-effectively at those lakes at the highest risk of breaching World Health Organisation guideline levels for cyanobacteria in recreational waters. The models also inform restoration options available for reducing cyanobacterial blooms, indicating that, in the highest risk lakes (alkaline, low colour lakes), risks can generally be lessened through management aimed at reducing nutrient loads and increasing flushing during summer.

Reconstructing the abundance of Dounreay hot particles on an adjacent public beach in Northern Scotland.

Following the discovery of a number of hot particles in the offshore environment of Dounreay on the North Coast of Scotland in 1997, the Dounreay site operator was required to introduce rapid and extensive beach monitoring. Since the introduction of vehicular based beach monitoring in 1999 there have been two further generations of beach monitoring equipment, developed to satisfy regulatory requirements for particle detection and in response to the recommendations of the Dounreay Particles Advisory Group (DPAG). This paper reports the results of DPAG's review of beach monitoring capabilities, evaluating the factors influencing detection capability, assessing the likely monthly particle abundance and whether there has been any real change in particle arrivals with time. The incorporation of real time kinematic GPS has enabled changes in beach elevation to be mapped, and thus allowed the assessment of whether particles detected have recently arrived or may have been buried undisturbed for extended periods of time. The results focus on Sandside Beach from which, between 1984 and December 2009, 150 particles have been recovered. This is by far the largest number of particles found on a Caithness Beach with the exception of the Foreshore of the Dounreay site. The results suggested that there is no evidence for a change in the rate of particle arrivals and DPAG estimated that there is a 1 in 20 million chance of encountering a relevant particle via contact with the skin on Sandside Beach.

Using remote sensing to aid the assessment of human health risks from blooms of potentially toxic cyanobacteria.

Mass populations of toxic cyanobacteria in recreational waters can present a serious risk to human health. Intelligence on the abundance and distribution of cyanobacteria is therefore needed to aid risk assessment and management activities. In this paper, we use data from the Compact Airborne Spectrographic Imager-2 (CASI-2) to monitor seasonal change in the concentration of chlorophyll a (Chl a) and the cyanobacterial biomarker pigment C-phycocyanin (C-PC) in a series of shallow lakes in the U.K. The World Health Organization guidance levels for cyanobacteria in recreational waters were subsequently used to build a decision tree classification model for cyanobacterial risk assessment which was driven using Chl a and C-PC products derived from the CASI-2 data. The results demonstrate that remote sensing can be used to acquire intelligence on the distribution and abundance of cyanobacteria in inland waterbodies. It is argued the use of remote sensing reconnaissance, in conjunction with in situ based monitoring approaches, would greatly aid the assessment of cyanobacterial risks in inland waters and improve our ability to protect human health.