Environmental geochemistry of the abandoned Mamut Copper Mine (Sabah) Malaysia

The Mamut Copper Mine (MCM) located in Sabah (Malaysia) on Borneo Island was the only Cu–Au mine that operated in the country. During its operation (1975–1999), the mine produced 2.47 Mt of concentrate containing approximately 600,000 t of Cu, 45 t of Au and 294 t of Ag, and generated about 250 Mt of overburden and waste rocks and over 150 Mt of tailings, which were deposited at the 397 ha Lohan tailings storage facility, 15.8 km from the mine and 980 m lower in altitude. The MCM site presents challenges for environmental rehabilitation due to the presence of large volumes of sulphidic minerals wastes, the very high rainfall and the large volume of polluted mine pit water. This indicates that rehabilitation and treatment is costly, as for example, exceedingly large quantities of lime are needed for neutralisation of the acidic mine pit discharge. The MCM site has several unusual geochemical features on account of the concomitant occurrence of acidforming sulphide porphyry rocks and alkaline serpentinite minerals, and unique biological features because of the very high plant diversity in its immediate surroundings. The site hence provides a valuable opportunity for researching natural acid neutralisation processes and mine rehabilitation in tropical areas. Today, the MCM site is surrounded by protected nature reserves (Kinabalu Park, a World Heritage Site, and Bukit Hampuan, a Class I Forest Reserve), and the environmental legacy prevents degazetting and inclusion in these protected area in the foreseeable future. This article presents a preliminary geochemical investigation of waste rocks, sediments, secondary precipitates, surface water chemistry and foliar elemental uptake in ferns, and discusses these results in light of their environmental significance for rehabilitation

Evaluating soil extraction methods for chemical characterization of ultramafic soils in Kinabalu Park (Malaysia)

Soils derived from ultramafic bedrock are known for hosting distinct vegetation types as a consequence of atypical soil chemistries consisting of high trace elements concentrations (Ni, Cr, Co) and exchangeable cation imbalances (high Mg:Ca quotients). Ecological studies use a range of single-stage extraction methods for chemical characterization of such soils in order to be able to interpret plant response, and ultimately to explain plant community composition. Few studies to date have compared different soil extraction methods in relation to tropical ultramafic soils. This study compares eight commonly used extraction methods on a large number of ultramafic soil samples collected from Kinabalu Park (Malaysia). The tested methods were: for trace elements: NH4AC, DTPA, CaCl2, Sr(NO3)2 and Mehlich-3, for exchangeable cations: NH4Ac and silverthiorea, and for plant-available phosphorus: Mehlich-3 and Olsen-P. These single-stage extraction methods were compared and evaluated for predictive power for chemically characterizing soils, interrelatedness and ecological application. The methods were also contrasted with a sequential extraction scheme. Finally, several operational parameters including molar ratio (0.01 and 0.1 M CaCl2, Sr(NO3)2) and pH buffering (DTPA-TEA) were also evaluated. The majority of single-stage extraction methods are highly inter-correlated and predictive power could be improved by including independent soil parameters (pH, CEC, pseudo-total element concentration) in the multivariate regression equation. Ecological interpretation remains difficult because of lack of experimental studies in relation to plant uptake response and potential phytotoxicity effects on tropical native plants from ultramafic soils

Mediterranean ocean Forecasting System: Toward Environmental Predictions-MFSTEP Executive Summary

Objectives: The Project aims at the further development of an operational forecasting system for the Mediterranean Sea based upon three main components: a) a Real Time-RT Observing system; b) a numerical forecasting system at the basin scale and for the sub-regional/shelf areas; c) the forecast products dissemination/exploitation system. The Observing system component consists of: • a SOOP-VOS system with RT data dissemination and test of new sensors that collect multidisciplinary data; • a moored buoy network (M3A) designed to serve the RT validation of the basin scale models and the calibration of the ecosystem models; • a satellite RT data analysis system using several satellites for sea surface elevation, sea surface temperature and sea surface winds; • a high space-time resolution network of autonomous subsurface profiling floats (Array for Real-Time Geostrophic Oceanography-ARGO); • a basin scale glider autonomous vehicle experiment; The sampling strategy is continuously assessed by the Observing System Simulation Experiment (OSSE) activities and a RT data management and delayed mode archiving system has been organized

Impacts of ultramafic outcrops in Peninsular Malaysia and Sabah on soil and water quality

This study focused on the influence of ultramafic terrains on soil and surface water environmental chemistry in Peninsular\ua0Malaysia and\ua0in\ua0the State of Sabah also in\ua0Malaysia. The sampling included 27 soils from four isolated outcrops at\ua0Cheroh, Bentong, Bukit Rokan, and Petasih from Peninsular Malaysia and sites near Ranau in\ua0Sabah. Water samples were also collected from rivers and subsurface waters interacting with the ultramafic bodies in these study sites. Physico-chemical parameters (including pH, EC, CEC) as well as the concentration of major and trace elements were measured in these soils and waters. Geochemical indices (geoaccumulation index, enrichment factor, and concentration factor) were calculated. AlO and FeO had\ua0relatively high concentrations in the samples. A depletion in MgO, CaO, and NaO was observed as a result of leaching in tropical climate, and in relation to weathering and pedogenesis processes. Chromium, Ni, and Co were enriched and confirmed by the significant values obtained for Igeo, EF, and CF, which correspond to the extreme levels of contamination for Cr and high to moderate levels of contamination for Ni and Co. The concentrations of Cr, Ni, and Co in surface waters did not reflect the local geochemistry and were within the permissible ranges according to WHO and INWQS standards. Subsurface waters were strongly enriched by these elements and exceeded these standards. The association between Cr and Ni was confirmed by factor analysis. The unexpected enrichment of Cu in an isolated component can be explained by localized mineralization in Sabah

Metallophytes on Zn-Pb mineralised soils and mining wastes in Broken Hill, NSW, Australia

The wastes of metalliferous mining activities produce a substrate that is generally unfavourable for normal plant establishment and growth. However, metallophytes have evolved to grow in hostile environments that are rich in metals. They possess key properties that commend them for revegetation of mines and metal-contaminated sites. This field survey aimed to identify native metallophytes occurring on minerals wastes and mineralised outcrops in Broken Hill (New South Wales, Australia). Foliar concentrations of minerals were very high compared with non-mineralised soils but within the range expected for plants in such environments. Neither hyperaccumulators nor obligate metallophytes have been found, but they may be present on isolated mineralised outcrops in the wider Broken Hill area; however, a range of facultative metallophytes was identified in this study. These species could be introduced onto mining leases if establishment protocols for such species were developed

Contrasting nickel and zinc hyperaccumulation in subspecies of Dichapetalum gelonioides from Southeast Asia

Hyperaccumulator plants have the unique ability to concentrate specific elements in their shoot in concentrations that can be thousands of times greater than in normal plants. Whereas all known zinc hyperaccumulator plants are facultative hyperaccumulators with only populations on metalliferous soils hyperaccumulating zinc (except for Arabidopsis halleri and Noccaea species that hyperaccumulate zinc irrespective of the substrate), the present study discovered that Dichapetalum gelonioides is the only (zinc) hyperaccumulator known to occur exclusively on 'normal' soils, while hyperaccumulating zinc. We recorded remarkable foliar zinc concentrations (10 730 µg g, dry weight) in Dichapetalum gelonioides subsp. sumatranum growing on 'normal' soils with total soil zinc concentrations of only 20 µg g. The discovery of zinc hyperaccumulation in this tropical woody plant, especially the extreme zinc concentrations in phloem and phloem-fed tissues (reaching up to 8465 µg g), has possible implications for advancing zinc biofortification in Southeast Asia. Furthermore, we report exceptionally high foliar nickel concentrations in D. subsp. tuberculatum (30 260 µg g) and >10 wt% nickel in the ash, which can be exploited for agromining. The unusual nickel and zinc accumulation behaviour suggest that Dichapetalum-species may be an attractive model to study hyperaccumulation and hypertolerance of these elements in tropical hyperaccumulator plants

Simultaneous hyperaccumulation of nickel and cobalt in the tree Glochidion cf. sericeum (Phyllanthaceae): elemental distribution and chemical speciation

Hyperaccumulation is generally highly specific for a single element, for example nickel (Ni). The recently-discovered hyperaccumulator Glochidion cf. sericeum (Phyllanthaceae) from Malaysia is unusual in that it simultaneously accumulates nickel and cobalt (Co) with up to 1500 μg g foliar of both elements. We set out to determine whether distribution and associated ligands for Ni and Co complexation differ in this species. We postulated that Co hyperaccumulation coincides with Ni hyperaccumulation operating on similar physiological pathways. However, the ostensibly lower tolerance for Co at the cellular level results in the exudation of Co on the leaf surface in the form of lesions. The formation of such lesions is akin to phytotoxicity responses described for manganese (Mn). Hence, in contrast to Ni, which is stored principally inside the foliar epidermal cells, the accumulation response to Co consists of an extracellular mechanism. The chemical speciation of Ni and Co, in terms of the coordinating ligands involved and principal oxidation state, is similar and associated with carboxylic acids (citrate for Ni and tartrate or malate for Co) and the hydrated metal ion. Some oxidation to Co, presumably on the surface of leaves after exudation, was observed