SEGH Articles

# Centre for Environmental Geochemistry

15 June 2014
The Centre's research will focus on building established collaborations between the University of Nottingham and the British Geological Survey (across Departments, Schools and Faculties).

The Centre for Environmental Geochemistry combines the University of Nottingham's (UoN) and the British Geological Survey's (BGS) strengths, focussing on the use of geochemistry in research, training and teaching around reconstructing past environmental and climate change, biogeochemical cycling including pollution typing/provenance and the use of geochemical tools for research into the subsurface. The Centre's research will focus on building established collaborations between the University and BGS (across Departments, Schools and Faculties).

Photo shows Prof David Greenaway (UoN) and Prof John Ludden (BGS) signing the collaboration agreement

The Centre is initially focussed around three laboratories in BGS: the Stable Isotope Laboratory (part of the NERC Isotope Geosciences Facilities, governed by BGS) led by Professor Melanie Leng; the Inorganic Geochemistry Laboratory led by Dr Michael Watts and the Organic Geochemistry Laboratory led by Dr Christopher Vane. The three main areas within the university are the School of Biosciences, the School of Geography, and the Faculty of Engineering.

The Centre for Environmental Geohemistry will focus initially on the following topics:

Past Environmental and Climate Change

The Centre will use geochemistry to understand and measure climate and environmental change over decadal to millennial timescales both in the recent and geological past. This enables the understanding of local and regional impacts of climate variability, changing land and river management practices on hydrological processes, impacts of pollution, effects on sea level etc. The Centre will invest significantly to extend geochemical tracer work into several global projects including investigating current and past freshwater contributions into the polar oceans and effects on ocean circulation; climate influences over significant land masses (e.g. tropical Americas, Northern Europe) over time and effects on plant and animal migration and endemism, desertification/water resources etc; climate-driven human evolution, innovation, and dispersal through Africa and understanding the role of mangrove and wetland habitats as sources/sinks of carbon under different climate regimes as well as developing geochemical techniques. Several of these projects will fall within the remit of NERC, the International Continental scientific Drilling Program (ICDP) and the International Ocean Discovery Program (IODP).

Biogeochemical cycling

Biogeochemical cycling of nutrients and pollutants is a key research area especially in relation to food security and understanding land-use change, in particular urban agriculture and protecting food production from exposure to potentially harmful contaminants; efficient application of fertilisers/agricultural techniques and the understanding of mineral deficiency in sub-Saharan African and Indian sub-continental soils. Improving our understanding of the linkages between soil composition/inputs, plant uptake of minerals/pollutants and subsequent impact on dietary and health status requires investigation and can be done using joint BGS-University of Nottingham expertise. This type of research influences regional government policy especially with regard to remedial strategies the most significant of which concerns mineral biofortification which has huge impacts on improving people's lives in developing countries.

Geochemistry and the subsurface

An ambition of the new centre will be to build on the geochemistry, geomechanical, geological, soil and biogeochemical expertise in BGS and University of Nottingham to research practical problems relating to use of the shallow and deep subsurface in developing resources. This project will build on a BGS-led infrastructure project 'Energy test bed: multicomponent sub-surface monitoring to underpin the UK energy industry', a research infrastructure to allow the subsurface to be monitored at time scales that are consistent with our use of the subsurface, to increase efficiency and environmental sustainability and to act as a catalyst to stimulate investment and speed new technology energy options to commercialisation. In particular research will look towards understanding the impact of deep shale gas drilling and hydraulic fracturing on the quality of shallow groundwater and surface water; studies on the impact of coal combustion products on the environment both from surface and subsurface operations; contaminants associated with mining in valley fill head waters; and water usage implications of widespread carbon capture and storage (CCS) and shale gas.

by Dr Michael Watts, Head of Inorganic Geochemistry, BGS.

Keep up to date

## 34th SEGH International Conference: Geochemistry for Sustainable Development

Victoria Falls, Zambia

02 July 2018

## SubmitContent

Members can keep in touch with their colleagues through short news and events articles of interest to the SEGH community.

## Science in theNews

Latest on-line papers from the SEGH journal: Environmental Geochemistry and Health

• Fertilizer usage and cadmium in soils, crops and food 2018-06-23

### Abstract

Phosphate fertilizers were first implicated by Schroeder and Balassa (Science 140(3568):819–820, 1963) for increasing the Cd concentration in cultivated soils and crops. This suggestion has become a part of the accepted paradigm on soil toxicity. Consequently, stringent fertilizer control programs to monitor Cd have been launched. Attempts to link Cd toxicity and fertilizers to chronic diseases, sometimes with good evidence, but mostly on less certain data are frequent. A re-assessment of this “accepted” paradigm is timely, given the larger body of data available today. The data show that both the input and output of Cd per hectare from fertilizers are negligibly small compared to the total amount of Cd/hectare usually present in the soil itself. Calculations based on current agricultural practices are used to show that it will take centuries to double the ambient soil Cd level, even after neglecting leaching and other removal effects. The concern of long-term agriculture should be the depletion of available phosphate fertilizers, rather than the negligible contamination of the soil by trace metals from fertilizer inputs. This conclusion is confirmed by showing that the claimed correlations between fertilizer input and Cd accumulation in crops are not robust. Alternative scenarios that explain the data are presented. Thus, soil acidulation on fertilizer loading and the effect of Mg, Zn and F ions contained in fertilizers are considered using recent $$\hbox {Cd}^{2+}$$ , $$\hbox {Mg}^{2+}$$ and $$\hbox {F}^-$$ ion-association theories. The protective role of ions like Zn, Se, Fe is emphasized, and the question of Cd toxicity in the presence of other ions is considered. These help to clarify difficulties in the standard point of view. This analysis does not modify the accepted views on Cd contamination by airborne delivery, smoking, and industrial activity, or algal blooms caused by phosphates.

• Effects of conversion of mangroves into gei wai ponds on accumulation, speciation and risk of heavy metals in intertidal sediments 2018-06-23

### Abstract

Mangroves are often converted into gei wai ponds for aquaculture, but how such conversion affects the accumulation and behavior of heavy metals in sediments is not clear. The present study aims to quantify the concentration and speciation of heavy metals in sediments in different habitats, including gei wai pond, mangrove marsh dominated by Avicennia marina and bare mudflat, in a mangrove nature reserve in South China. The results showed that gei wai pond acidified the sediment and reduced its electronic conductivity and total organic carbon (TOC) when compared to A. marina marsh and mudflat. The concentrations of Cd, Cu, Zn and Pb at all sediment depths in gei wai pond were lower than the other habitats, indicating gei wai pond reduced the fertility and the ability to retain heavy metals in sediment. Gei wai pond sediment also had a lower heavy metal pollution problem according to multiple evaluation methods, including potential ecological risk coefficient, potential ecological risk index, geo-accumulation index, mean PEL quotients, pollution load index, mean ERM quotients and total toxic unit. Heavy metal speciation analysis showed that gei wai pond increased the transfer of the immobilized fraction of Cd and Cr to the mobilized one. According to the acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) analysis, the conversion of mangroves into gei wai pond reduced values of ([SEM] − [AVS])/f oc , and the role of TOC in alleviating heavy metal toxicity in sediment. This study demonstrated the conversion of mangrove marsh into gei wai pond not only reduced the ecological purification capacity on heavy metal contamination, but also enhanced the transfer of heavy metals from gei wai pond sediment to nearby habitats.

• Cytotoxicity induced by the mixture components of nickel and poly aromatic hydrocarbons 2018-06-22

### Abstract

Although particulate matter (PM) is composed of various chemicals, investigations regarding the toxicity that results from mixing the substances in PM are insufficient. In this study, the effects of low levels of three PAHs (benz[a]anthracene, benzo[a]pyrene, and dibenz[a,h]anthracene) on Ni toxicity were investigated to assess the combined effect of Ni–PAHs on the environment. We compared the difference in cell mortality and total glutathione (tGSH) reduction between single Ni and Ni–PAHs co-exposure using A549 (human alveolar carcinoma). In addition, we measured the change in Ni solubility in chloroform that was triggered by PAHs to confirm the existence of cation–π interactions between Ni and PAHs. In the single Ni exposure, the dose–response curve of cell mortality and tGSH reduction were very similar, indicating that cell death was mediated by the oxidative stress. However, 10 μM PAHs induced a depleted tGSH reduction compared to single Ni without a change in cell mortality. The solubility of Ni in chloroform was greatly enhanced by the addition of benz[a]anthracene, which demonstrates the cation–π interactions between Ni and PAHs. Ni–PAH complexes can change the toxicity mechanisms of Ni from oxidative stress to others due to the reduction of Ni2+ bioavailability and the accumulation of Ni–PAH complexes on cell membranes. The abundant PAHs contained in PM have strong potential to interact with metals, which can affect the toxicity of the metal. Therefore, the mixture toxicity and interactions between diverse metals and PAHs in PM should be investigated in the future.