Marc Peters
Chinese Academy of Sciences
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Marc Peters.
Nature | 2007
James Farquhar; Marc Peters; David T. Johnston; Harald Strauss; Andrew Masterson; Uwe Wiechert; Alan J. Kaufman
The evolution of the Earth’s atmosphere is marked by a transition from an early atmosphere with very low oxygen content to one with an oxygen content within a few per cent of the present atmospheric level. Placing time constraints on this transition is of interest because it identifies the time when oxidative weathering became efficient, when ocean chemistry was transformed by delivery of oxygen and sulphate, and when a large part of Earth’s ecology changed from anaerobic to aerobic. The observation of non-mass-dependent sulphur isotope ratios in sedimentary rocks more than ∼2.45 billion years (2.45 Gyr) old and the disappearance of this signal in younger sediments is taken as one of the strongest lines of evidence for the transition from an anoxic to an oxic atmosphere around 2.45 Gyr ago. Detailed examination of the sulphur isotope record before 2.45 Gyr ago also reveals early and late periods of large amplitude non-mass-dependent signals bracketing an intervening period when the signal was attenuated. Until recently, this record has been too sparse to allow interpretation, but collection of new data has prompted some workers to argue that the Mesoarchaean interval (3.2–2.8 Gyr ago) lacks a non-mass-dependent signal, and records the effects of earlier and possibly permanent oxygenation of the Earth’s atmosphere. Here we focus on the Mesoarchaean interval, and demonstrate preservation of a non-mass-dependent signal that differs from that of preceding and following periods in the Archaean. Our findings point to the persistence of an anoxic early atmosphere, and identify variability within the isotope record that suggests changes in pre-2.45-Gyr-ago atmospheric pathways for non-mass-dependent chemistry and in the ultraviolet transparency of an evolving early atmosphere.
Geochemistry Geophysics Geosystems | 2007
Karsten M. Haase; Sven Petersen; Andrea Koschinsky; Richard Seifert; C. W. Devey; R. Keir; Klas Lackschewitz; Bernd Melchert; Mirjam Perner; Oliver Schmale; J. Süling; Nicole Dubilier; Frank Zielinski; S. Fretzdorff; Dieter Garbe-Schönberg; Ulrike Westernströer; Christopher R. German; Timothy M. Shank; Dana R. Yoerger; O. Giere; Jan Kuever; H. Marbler; J. Mawick; Christian Mertens; Uwe Stöber; Maren Walter; C. Ostertag‐Henning; Holger Paulick; Marc Peters; Harald Strauss
The effect of volcanic activity on submarine hydrothermal systems has been well documented along fast- and intermediate-spreading centers but not from slow-spreading ridges. Indeed, volcanic eruptions are expected to be rare on slow-spreading axes. Here we report the presence of hydrothermal venting associated with extremely fresh lava flows at an elevated, apparently magmatically robust segment center on the slow-spreading southern Mid-Atlantic Ridge near 5°S. Three high-temperature vent fields have been recognized so far over a strike length of less than 2 km with two fields venting phase-separated, vapor-type fluids. Exit temperatures at one of the fields reach up to 407°C, at conditions of the critical point of seawater, the highest temperatures ever recorded from the seafloor. Fluid and vent field characteristics show a large variability between the vent fields, a variation that is not expected within such a limited area. We conclude from mineralogical investigations of hydrothermal precipitates that vent-fluid compositions have evolved recently from relatively oxidizing to more reducing conditions, a shift that could also be related to renewed magmatic activity in the area. Current high exit temperatures, reducing conditions, low silica contents, and high hydrogen contents in the fluids of two vent sites are consistent with a shallow magmatic source, probably related to a young volcanic eruption event nearby, in which basaltic magma is actively crystallizing. This is the first reported evidence for direct magmatic-hydrothermal interaction on a slow-spreading mid-ocean ridge.
Geobiology | 2014
Benjamin Eickmann; Ingunn H. Thorseth; Marc Peters; Harald Strauss; Michael Bröcker; Rolf B. Pedersen
Barite chimneys are known to form in hydrothermal systems where barium-enriched fluids generated by leaching of the oceanic basement are discharged and react with seawater sulfate. They also form at cold seeps along continental margins, where marine (or pelagic) barite in the sediments is remobilized because of subseafloor microbial sulfate reduction. We test the possibility of using multiple sulfur isotopes (δ34S, Δ33S, ∆36S) of barite to identify microbial sulfate reduction in a hydrothermal system. In addition to multiple sulfur isotopes, we present oxygen (δ18O) and strontium (87Sr/86Sr) isotopes for one of numerous barite chimneys in a low-temperature (~20 °C) venting area of the Lokis Castle black smoker field at the ultraslow-spreading Arctic Mid-Ocean Ridge (AMOR). The chemistry of the venting fluids in the barite field identifies a contribution of at least 10% of high-temperature black smoker fluid, which is corroborated by 87Sr/86 Sr ratios in the barite chimney that are less radiogenic than in seawater. In contrast, oxygen and multiple sulfur isotopes indicate that the fluid from which the barite precipitated contained residual sulfate that was affected by microbial sulfate reduction. A sulfate reduction zone at this site is further supported by the multiple sulfur isotopic composition of framboidal pyrite in the flow channel of the barite chimney and in the hydrothermal sediments in the barite field, as well as by low SO4 and elevated H2S concentrations in the venting fluids compared with conservative mixing values. We suggest that the mixing of ascending H2- and CH4-rich high-temperature fluids with percolating seawater fuels microbial sulfate reduction, which is subsequently recorded by barite formed at the seafloor in areas where the flow rate is sufficient. Thus, low-temperature precipitates in hydrothermal systems are promising sites to explore the interactions between the geosphere and biosphere in order to evaluate the microbial impact on these systems.
Ecotoxicology and Environmental Safety | 2016
Junxing Yang; Zhiyan Liu; Xiaoming Wan; Guodi Zheng; Jun Yang; Hanzhi Zhang; Lin Guo; Xuedong Wang; Xiaoyong Zhou; Qingjun Guo; Ruixiang Xu; Guangdong Zhou; Marc Peters; Guangxu Zhu; Rongfei Wei; Liyan Tian; Xiaokun Han
Human activities have resulted in lead and sulfur accumulation in paddy soils in parts of southern China. A combined soil-sand pot experiment was conducted to investigate the influence of S supply on iron plaque formation and Pb accumulation in rice (Oryza sativa L.) under two Pb levels (0 and 600 mg kg(-1)), combined with four S concentrations (0, 30, 60, and 120 mg kg(-1)). Results showed that S supply significantly decreased Pb accumulation in straw and grains of rice. This result may be attributed to the enhancement of Fe plaque formation, decrease of Pb availability in soil, and increase of reduced glutathione (GSH) in rice leaves. Moderate S supply (30 mg kg(-1)) significantly increased Fe plaque formation on the root surface and in the rhizosphere, whereas excessive S supply (60 and 120 mg kg(-1)) significantly decreased the amounts of iron plaque on the root surface. Sulfur supply significantly enhanced the GSH contents in leaves of rice plants under Pb treatment. With excessive S application, the rice root acted as a more effective barrier to Pb accumulation compared with iron plaque. Excessive S supply may result in a higher monosulfide toxicity and decreased iron plaque formation on the root surface during flooded conditions. However, excessive S supply could effectively decrease Pb availability in soils and reduce Pb accumulation in rice plants.
Journal of Environmental Sciences-china | 2014
Hanzhi Zhang; Qingjun Guo; Junxing Yang; Tongbin Chen; Guangxu Zhu; Marc Peters; Rongfei Wei; Liyan Tian; Chunyu Wang; Deyun Tan; Jie Ma; Gangming Wang; Yingxin Wan
To investigate the effects of Cd on tolerance and antioxidant activities of castor, two different castor (Ricinus communis L.) cultivars (Zibo No. 5 and Zibo No. 8) were used for a hydroponic experiment (0, 1 and 2mg/L Cd) and a pot experiment using Cd-contaminated soil (34mg/kg) with the addition of ethylenedinitrilotetraacetic acid (EDTA). The results indicated that there were significant differences between the two cultivars with respect to Cd uptake in shoots (113-248mg/kg for Zibo No. 5 and 130-288mg/kg Zibo No. 8), biomass tolerance indexes (64.9%-74.6% for Zibo No. 5 and 80.1%-90.9% for Zibo No. 8) in the hydroponic experiment and survival rates (0% for Zibo No. 5 and 100% for Zibo No. 8) determined by the addition of EDTA in the pot experiment, suggesting that Zibo No. 8 has higher tolerance than Zibo No. 5. Moreover, the castor cultivars have low bioconcentration factors (4.80% for Zibo No. 5 and 5.43% for Zibo No. 8) and low translocation factors (<1%). Consequently, Zibo No. 8 can participate in Cd phytostabilization in highly Cd-polluted areas. The results indicated that glutathione (GSH) as a non-enzymatic antioxidant, and antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (GPX), were cultivar- and dose-dependent. The higher tolerance of Zibo No. 8 compared with Zibo No. 5 can be attributed to the higher GSH levels in the root and higher GPX activity in the leaf.
Proceedings of the National Academy of Sciences of the United States of America | 2014
Michael A. Antonelli; Marc Peters; Jabrane Labidi; Pierre Cartigny; Richard J. Walker; James R. Lyons; Joost Hoek; James Farquhar
Significance This investigation focuses on the sulfur isotopic compositions of magmatically differentiated meteorites, the oldest igneous rocks in our solar system. We present evidence of anomalous 33S depletions in a group of differentiated iron meteorites, along with 33S enrichments in several other groups. The complementary positive and negative compositions, along with observed covariations in 36S and 33S, are explained by Lyman-α photolysis of gaseous H2S in the solar nebula. Confirmation of photochemically predicted 33S depletions implies that the starting composition of inner solar system sulfur was chondritic, consistent with the Earth, Moon, Mars, and nonmagmatic iron meteorites. Differentiated protoplanets, however, appear to have accreted from materials processed under conditions where sulfur was volatile and UV radiation was present (<∼2 AU). Achondrite meteorites have anomalous enrichments in 33S, relative to chondrites, which have been attributed to photochemistry in the solar nebula. However, the putative photochemical reactions remain elusive, and predicted accompanying 33S depletions have not previously been found, which could indicate an erroneous assumption regarding the origins of the 33S anomalies, or of the bulk solar system S-isotope composition. Here, we report well-resolved anomalous 33S depletions in IIIF iron meteorites (<−0.02 per mil), and 33S enrichments in other magmatic iron meteorite groups. The 33S depletions support the idea that differentiated planetesimals inherited sulfur that was photochemically derived from gases in the early inner solar system (<∼2 AU), and that bulk inner solar system S-isotope composition was chondritic (consistent with IAB iron meteorites, Earth, Moon, and Mars). The range of mass-independent sulfur isotope compositions may reflect spatial or temporal changes influenced by photochemical processes. A tentative correlation between S isotopes and Hf-W core segregation ages suggests that the two systems may be influenced by common factors, such as nebular location and volatile content.
Environmental Pollution | 2013
Qingjun Guo; Harald Strauss; Tongbin Chen; Guangxu Zhu; Jun Yang; Junxing Yang; Mei Lei; Xiaoyong Zhou; Marc Peters; Yunfeng Xie; Hanzhi Zhang; Rongfei Wei; Chunyu Wang
Bulk soil organic carbon concentration and isotopic composition characterize its sources and fate, identify the anthropogenic input of organic carbon into the soil, and trace soil carbon turnover. Coal and/or coal combustion products represent the prime anthropogenic input of organic carbon into three soil profiles located in the vicinity of a steel company. Three profiles positioned away from any direct industrial contribution display vertical pattern in soil organic carbon concentration and isotopic composition that resemble more commonly observed downward gradients in soil carbon chemistry and indicate microbial soil carbon turnover. Two additional profiles located outside of the immediate industrial area display vertical carbon isotope profiles between typical of those from industrial and non-industrial areas. Eight soil profiles and their vertical distribution of bulk organic carbon isotopic composition and concentration collected in the Beijing area reveal and distinguish both anthropogenic and natural contributions of carbon to these soils.
Analytical Methods | 2015
Rongfei Wei; Qingjun Guo; Hanjie Wen; Junxing Yang; Marc Peters; Chuanwei Zhu; Jie Ma; Guangxu Zhu; Hanzhi Zhang; Liyan Tian; Chunyu Wang; Yingxin Wan
Isotope techniques can be applied to discover the migration and transformation of metal elements in plants. However, only a few studies on Cd isotopes in plants have been carried out so far. In this study, an optimized analytical method consisting of digestion, purification and determination of Cd isotopes in plants was developed. Three Cd standard solutions as well as four plant species (Solanum nigrum, Ricinus communis, Cyperus alternifolius and Pteris vittata), which were grown in soil or hydroponic cultures, were repeatedly analyzed for Cd isotopes using Multiple Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS). The factors that affected the accuracy of Cd isotopic determination, such as isobaric interference and instrumental mass fractionation, have been carefully evaluated and corrected. The purification procedure yielded a Cd recovery of not less than 95% and effectively eliminated the spectral interference of Pd, In and Sn as well. The analysis of pure Cd standard materials showed accurate isotope values, which matched with the results of previously published methods. This technique provided an average long-term external reproducibility of ±0.09‰ for δ114/110Cd (2SD). The overall δ114/110Cd values of four plant species ranged from −0.39‰ to −0.08‰ and provided direct evidence for Cd isotopic fractionation in herbaceous plants.
Scientific Reports | 2016
Xiaokun Han; Qingjun Guo; Cong-Qiang Liu; Pingqing Fu; Harald Strauss; Junxing Yang; Jian Hu; Lianfang Wei; Hong Ren; Marc Peters; Rongfei Wei; Liyan Tian
Particulate pollution from anthropogenic and natural sources is a severe problem in China. Sulfur and oxygen isotopes of aerosol sulfate (δ34Ssulfate and δ18Osulfate) and water-soluble ions in aerosols collected from 2012 to 2014 in Beijing are being utilized to identify their sources and assess seasonal trends. The mean δ34S value of aerosol sulfate is similar to that of coal from North China, indicating that coal combustion is a significant contributor to atmospheric sulfate. The δ34Ssulfate and δ18Osulfate values are positively correlated and display an obvious seasonality (high in winter and low in summer). Although an influence of meteorological conditions to this seasonality in isotopic composition cannot be ruled out, the isotopic evidence suggests that the observed seasonality reflects temporal variations in the two main contributions to Beijing aerosol sulfate, notably biogenic sulfur emissions in the summer and the increasing coal consumption in winter. Our results clearly reveal that a reduction in the use of fossil fuels and the application of desulfurization technology will be important for effectively reducing sulfur emissions to the Beijing atmosphere.
Scientific Reports | 2016
Rongfei Wei; Qingjun Guo; Hanjie Wen; Cong-Qiang Liu; Junxing Yang; Marc Peters; Jian Hu; Guangxu Zhu; Hanzhi Zhang; Liyan Tian; Xiaokun Han; Jie Ma; Chuanwei Zhu; Yingxin Wan
Cadmium (Cd) isotopes provide new insights into Cd uptake, transport and storage mechanisms in plants. Therefore, the present study adopted the Cd-tolerant Ricinus communis and Cd-hyperaccumulator Solanum nigrum, which were cultured under controlled conditions in a nutrient solution with variable Cd supply, to test the isotopic fractionation of Cd during plant uptake. The Cd isotope compositions of nutrient solutions and organs of the plants were measured by multiple collector inductively coupled plasma mass spectrometry (MC-ICPMS). The mass balance of Cd isotope yields isotope fractionations between plant and Cd source (δ114/110Cdorgans-solution) of −0.70‰ to −0.22‰ in Ricinus communis and −0.51‰ to −0.33‰ in Solanum nigrum. Moreover, Cd isotope fractionation during Cd transport from stem to leaf differs between the Cd-tolerant and -hyperaccumulator species. Based on these results, the processes (diffusion, adsorption, uptake or complexation), which may induce Cd isotope fractionation in plants, have been discussed. Overall, the present study indicates potential applications of Cd isotopes for investigating plant physiology.