Earthworm Calcite Granule —A New Proxy for Paleoenvironmental Reconstruction
Zong Xiulan1, 2, , Song Yougui1, *, , Li Yue1, 2
1.State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China2.University of the Chinese Academy of Sciences, Beijing 100049, China
First author:Zong Xiulan(1995-),female,Yining City,Xinjiang Uygur Autonomous Region, Master student. Research areas include loess in Central Asia and climate change in the Quaternary. E-mail:zongxiulan@ieecas.cn
Earthworm calcite granules (ECG), generally produced in Morren's glands of the earthworm Lumbricus terrestris and Lumbricus rubellus, are commonly preserved in Quaternary soils and sediments well. These granules can not only provide radio-carbon dating (Carbon-14) with the efficacious materials, but accurately record a wealth of climatic and environmental information on temperature and precipitation. For instance, researchers from France reconstructed the paleotemperature and paleoprecipitation during the last glacial in west part of Europe by taking advantage of δ18O and δ13C signal contained in ECG. Additionally, scientists from Germany and France carried out radiocarbon dating of ECG from two different loess-paleosol sequences, and the results showed consistency with the dating results of other materials (such as charcoal, bone, plant calcified root cells, etc.). Therefore, this new bio-indicator has been confirmed as a proxy for paleoenvironmental and paleoclimatic reconstruction, hopefully becoming the golden key to understanding the paleoclimate change. This paper, based on the previous literatures, reviewed the present research status of ECG in paleoclimatology, mainly consisting of five aspects: (i) ECGs' production mechanism and their characteristics; (ii) The theoretical foundation of stable carbon and oxygen isotopes in terrestrial fossil earthworm calcite granules for paleoclimatic reconstruction; (iii) The pre-treatment of ECG samples; (iv) Current applications in chronology and paleoclimatology of earthworm calcite granules;(v) Major problems at present regarding paleoclimatic explanation and radiocarbon-14 dating of ECG. Finally, we proposed the future research and development direction in this field, which is expected to make a reference to the future researches.
Fig.1 Position where the Earthworm Calcite Granule (ECG) is produced within the body of earthworm and morphology features and interior structure of the ECG (modified after reference[6]) (a) The position of calciferous glands in earthworm[11,12]; (b) Scanning Electron Microscopy of an ECG produced by Lumbricus terrestris; (c) Micrograph of one ECG; (d) Thin section of an ECG
Pustovoytov等[8]初步将ECG用于黄土的定年当中。他们选取了位于德国西南部Schattenhausen的黄土—古土壤序列,对其中的钙化根系细胞、软体动物碳酸盐壳体和ECG同时进行了放射性14C测年,并对比了三者的测年结果 (图4)。其中软体动物壳体的放射性碳年龄为 (23 990±160) a BP,ECG的放射性碳年龄为 (24 510±190) a BP,二者都属于晚更新世,而钙化根系细胞得出的年龄偏年轻,可能受到成岩蚀变作用的影响,其结果落到了全新世范围内。
Fig.5 Radiocarbon chronology of all soil horizons from the Nussloch P4-P8 composite loess profile based on earthworm granules and correlations with Greenland Interstadials[7] Discarded ages are red-contoured; The gray shading indicates 2σ ranges of 14C ages
在年代学研究中,除了使用放射性14C测年,还可以用铀系测年法对ECG进行测年[4,7,9]。例如,Versteegh等[4]通过对英国威尔特郡Silbury Hill遗址中ECG进行U-Th不平衡定年,确定了该遗址形成年龄为(4 670±440 ) a BP,这与碳酸盐颗粒的铀系年龄较一致,表明它们与土壤的形成处于同一时期,确定了该遗址属于新石器时代。
如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7]。Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6)。由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度。
In this paper we show for the first time that calcite granules, produced by the earthworm Lumbricus terrestris, and commonly recorded at sites of archaeological interest, accurately reflect temperature and soil water δ18O values. Earthworms were cultivated in an orthogonal combination of two different (granule-free) soils moistened by three types of mineral water and kept at three temperatures (10, 16 and 20°C) for an acclimatisation period of three weeks followed by transfer to identical treatments and cultivation for a further four weeks. Earthworm-secreted calcite granules were collected from the second set of soils. δ18O values were determined on individual calcite granules (δ18Oc) and the soil solution (δ18Ow). The δ18Oc values reflect soil solution δ18Ow values and temperature, but are consistently enriched by 1.51 (±0.12)‰ in comparison to equilibrium in synthetic carbonates. The data fit the equation 1000lnα=[20.21±0.92] (103T611)61[38.58±3.18] (R2=0.95; n=96; p<0.0005). As the granules are abundant in modern soils, buried soils and archaeological contexts, and can be dated using U–Th disequilibria, the developed palaeotemperature relationship has enormous potential for application to Holocene and Pleistocene time intervals.
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Prud'HommeCharlotte, AntoinePierre, MoineOlivier, et al.
Earthworm calcite granules: A new tracker of millennial-timescale environmental changes in last glacial loess deposits
<P>The ovoid calcium carbonate granules of less than 2 mm in size commonly found by molluscan specialists and soil micromorphologists are usually interpreted as coming from either earthworms or arionid slugs, or both. In this paper the granules are examined in detail, with a view to better understanding their origins and dynamics. Through collection and experiments, it is shown conclusively that both animals produce calcium carbonate granules of the right size range. The two types have distinctive morphologies, however, and most of the granules observed in soils and sediments are clearly identifiable as coming from earthworms. This arises from a far greater production rate: worms are capable of shedding granules at the rate of 1-3 per week, whereas Arion ater only yields around 40 granules < 250 m on death. The granules survive digestive processes, so heavy predation of earthworms by various animals and birds means that there is a constant recycling of the granules in the biosphere.</P>
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Conspicuous disturbances in archaeological sites are readily detected during excavation. However, one animal whose destructive effects are not often recognized is the earthworm. Work at the Carlston Annis mound in Kentucky, an Archaic shell midden, has resulted in the identification of areas of extensive earthworm disturbance. Archaeological sites most readily affected are those with the appropriate vegetation cover, moisture and temperature conditions, and available chemical elements. The type of disturbance a site will undergo depends on the species of earthworms present. Subsurface-casting species mix matrix only below the surface while surface-casting species bring the fine-grained matrix to the surface, thus concentrating larger objects below ground. If earthworm casts are identified in a profile, one should proceed cautiously with interpretations concerning soil matrix.
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Morphology and dynamics of calcium carbonate granules produced by different earthworm species: The 7th international symposium on earthworm ecology· cardiff· wales· 2002
The true function of the calciferous glands is excretion. The tendency for the worm cast to be more neutral than the soil is due to the secretions of the gut and not of the calciferous glands. Calcium carbonate is passed into the gut as crystals of calcite winch are chemically inactive in the gut. H. G. Smith.
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Research status and advance in carbon isotope (δ13C) variation from stalagmite
Plants with the C 3 , C 4 , and crassulacean acid metabolism (CAM) photosynthetic pathways show characteristically different discriminations against 13 C during photosynthesis. For each photosynthetic type, no more than slight variations are observed within or among species. CAM plants show large variations in isotope fractionation with temperature, but other plants do not. Different plant organs, subcellular fractions and metabolises can show widely varying isotopic compositions. The isotopic composition of respired carbon is often different from that of plant carbon, but it is not currently possible to describe this effect in detail. The principal components which will affect the overall isotope discrimination during photosynthesis are diffusion of CO 2 , interconversion of CO 2 and HCO 3 , incorporation of CO 2 by phosphoenolpyruvate carboxylase or ribulose bisphosphate carboxylase, and respiration. Theisotope fractionations associated with these processes are summarized. Mathematical models are presented which permit prediction of the overall isotope discrimination in terms of these components. These models also permit a correlation of isotope fractionations with internal CO 2 concentrations. Analysis of existing data in terms of these models reveals that CO 2 incorporation in C 3 plants is limited principally by ribulose bisphosphate carboxylase, but CO 2 diffusion also contributes. In C 4 plants, carbon fixation is principally limited by the rate of CO 2 diffusion into the leaf. There is probably a small fractionation in C 4 plants due to ribulose bisphosphate carboxylase.
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Experiments on the origin of 13C in the calcium carbonate granules produced by the earthworm lumbricus terrestris
Dating phases of pedogenesis, soil carbonate deposition or even the burial of whole soil profiles using 14 C is a valuable goal in archaeology and pedology, but one that has been consistently hampered by the presence of old carbon skewing the measurements to produce apparent dates older than the true formation date. Calcite produced by earthworms could be a useful alternative source of datable carbon. Since earthworms both inhabit and ingest soils with an old carbon content, however, the granules could yield a 14 C date older than the date of their formation. In this study, by examining granules from two sites of known-age stratigraphy, we show that the radiocarbon date derived from the granules' calcite closely reflects their true formation date, opening up the possibility of using the granules either individually or as distributions of dates to understand soil processes and date sealed archaeological layers.
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Experimental determination of salinity, temperature, growth, and metabolic effects on shell isotope chemistry of mytilus edulis collected from Maine and Greenland
Oxygen isotope fluctuations in a modern north sea oyster (crassostrea gigas) compared with annual variations in seawater temperature: Implications for palaeoclimate studies
A suite of divalent metal (Ca, Cd, Ba) carbonates was synthesized over the temperature range 10-40°C by the classical method of slowly bubbling N through a bicarbonate solution. It was discovered that carbonates could be precipitated reproducibly in or out of isotopic equilibrium with the environmental solution by varying the concentrations of bicarbonate and cation. Precipitation rate had little or no influence on the isotopic composition of the product. Relatively high initial concentrations of up to 25 mM in both bicarbonate and cation were prepared by adding solid metal chlorides to solutions of NaHC0 . On the basis of results of equilibrium experiments and a new determination of the acid fractionation factor, a new expression is proposed for the oxygen isotope fractionation between calcite and water at low temperatures: 10001nα(Calcite-H O) = 18.03(10 T ) - 32.42 where α is the fractionation factor, and T is in kelvins. Combining new data for low-temperature precipitations and the high-temperature equilibrium fractionations published by O'Neil et al. (1969) results in a revised expression for the oxygen isotope fractionation between octavite (CdCO ) and water from 0° to 500°C: 10001nα(CdC0P sbnd H O) = 2.7 (10 T ) - 3.96 The ability to produce nonequilibrium carbonates allowed assessment to be made, for the first time, of the temperature dependence of nonequilibrium stable isotope fractionations in mineral systems. The temperature coefficients of a(carbonate-water) for nonequilibrium divalent metal carbonates are greater than those for equilibrium carbonates, a finding that may bear on the interpretation of analyses of biogenic carbonates forming out of isotopic equilibrium in nature. New determinations of acid fractionation factors (10001nα) at 25°C for calcite (10.44 - 0.10), aragonite (11.01 ± 0.01), and witherite (10.57 - 0.16) are mildly to strongly different from those published by Sharma and Clayton (1965) and point to a control on this fractionation by some physical property of the mineral. Reproducible values for octavite (CdC0 ) varied from 11.18 to 13.60 depending on the conditions of preparation of the carbonate. These new values need to be considered in determinations of absolute 80 60 ratios of international reference standards and in relating analyses of carbonates to those of waters, silicates, and oxides.
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Revised carbonate-water isotopic temperature scale
The relationship between temperature and O(18) content relative to that for a Cretaceous belemnite of the Pee Dee formation previously reported (Epstein, Buchsbaum, Lowenstam, and Urey, 1951) has been re-determined using modified procedures for removing organic matter from shells, and is found to be t(°C) = 16.5 - 4.3δ + 0.14δ2 where δ is the difference in per mil of the O(18) to O(16) ratio between the sample and reference gas. The new relationship agrees with that determined by McCrea (1950) for inorganically precipitated calcium carbonate. Carbonate-carbon dioxide exchange experiments were done to determine the direct and indirect effects of organic matter in the shell on the mass spectrometer analyses.
Oxygen and carbon stable isotope composition of authigenic carbonates in loess sequences from the carpathian margin and podolia, as a palaeoclimatic record
[1] The presence of seasonal snow cover during the cold season of the annual air temperature cycle has significant influence on the ground thermal regime in cold regions. Snow has high albedo and emissivity that cool the snow surface, high absorptivity that tends to warm the snow surface, low thermal conductivity so that a snow layer acts as an insulator, and high latent heat due to snowmelt that is a heat sink. The overall impact of snow cover on the ground thermal regime depends on the timing, duration, accumulation, and melting processes of seasonal snow cover; density, structure, and thickness of seasonal snow cover; and interactions of snow cover with micrometeorological conditions, local microrelief, vegetation, and the geographical locations. Over different timescales either the cooling or warming impact of seasonal snow cover may dominate. In the continuous permafrost regions, impact of seasonal snow cover can result in an increase of the mean annual ground and permafrost surface temperature by several degrees, whereas in discontinuous and sporadic permafrost regions the absence of seasonal snow cover may be a key factor for permafrost development. In seasonally frozen ground regions, snow cover can substantially reduce the seasonal freezing depth. However, the influence of seasonal snow cover on seasonally frozen ground has received relatively little attention, and further study is needed. Ground surface temperatures, reconstructed from deep borehole temperature gradients, have increased by up to 4C in the past centuries and have been widely used as evidence of paleoclimate change. However, changes in air temperature alone cannot account for the changes in ground temperatures. Changes in seasonal snow conditions might have significantly contributed to the ground surface temperature increase. The influence of seasonal snow cover on soil temperature, soil freezing and thawing processes, and permafrost has considerable impact on carbon exchange between the atmosphere and the ground and on the hydrological cycle in cold regions/cold seasons.
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ZhangT, Osterkamp TE, StamnesK.
Effects of climate on the active layer and permafrost on the north slope of alaska, USA
Late Miocene climatic and environmental variations in northern Greece inferred from stable isotope compositions (delta O-18, delta C-13) of equid teeth apatite
The stable carbon isotope ratio of atmospheric CO2 (δ13Catm) is a key parameter in deciphering past carbon cycle changes. Here we present δ13Catm data for the past 24,000 years derived from three independent records from two Antarctic ice cores. We conclude that a pronounced 0.3 per mil decrease in δ13Catm during the early deglaciation can be best explained by upwelling of old, carbon-enriched waters in the Southern Ocean. Later in the deglaciation, regrowth of the terrestrial biosphere, changes in sea surface temperature, and ocean circulation governed the δ13Catm evolution. During the Last Glacial Maximum, δ13Catm and atmospheric CO2 concentration were essentially constant, which suggests that the carbon cycle was in dynamic equilibrium and that the net transfer of carbon to the deep ocean had occurred before then.
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HattéChristine, AntoinePierre, FontugneMichel, et al.
δ13C of loess organic matter as a potential proxy for paleoprecipitation
Paleoprecipitation reconstructions on the basis of pollen are well known, but they do not provide high temporal resolution for glacial periods. High-resolution paleoprecipitation reconstructions for the last glaciation based on the isotopic record organic matter in loess from Nussloch (Rhine Valley, Germany) are consistent with paleoprecipitation inferred from peat in the same area using an independant method. Thus, 13 C of loess organic matter can be used as a proxy for paleoprecipitation.
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Palaeoprecipitation reconstruction by inverse modelling using the isotopic signal of loess organic matter: Application to the Nussloch loess sequence (Rhine valley, Germany)
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GockeM, PustovoytovK, KühnP, et al.
Carbonate rhizoliths in loess and their implications for paleoenvironmental reconstruction revealed by isotopic composition:δ13C ,14C
Terrestrial mollusks, easily identified in Quaternary sediments, represent a reliable tool for quantitative estimates of environmental parameters. Our study, comparing the species distribution with meteorological parameters in Europe, shows that mean temperature of the coldest month and annual thermal magnitude are the most important forcing parameters. This survey allows us to adapt the mutual climatic range (MCR) method to terrestrial mollusk assemblages following two main steps. A set of assemblages from different European regions (northern Norway to southern France) is used to apply the method to present-day mollusks. The reconstructed values describe the latitudinal temperature gradient prevailing over Europe. However, the comparison between the reconstructed and the measured values indicates a shift, similar to that observed, with the same method applied to beetle assemblages. Thus, estimates must be calculated after the reconstruction is tuned with the observations. The results from the modern mollusk assemblages indicate that the MCR method can be safely applied to reconstructing temperatures from terrestrial mollusk assemblages in any worldwide Quaternary sequence. A trial application is made on Late Pleistocene assemblages from Achenheim (Alsace, France).
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XuQin.
Geographical distribution of terrestrial earthworms in China
... 如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7].Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6).由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度. ...
Earthworm calcite granules: A new tracker of millennial-timescale environmental changes in last glacial loess deposits
5
2015
... 陆生蚯蚓属于环节动物门寡毛纲后寡毛目,全球已记录的陆栖蚯蚓有12科,181属,约4 000种,生物量巨大,是典型的大型土壤动物之一[1,2,3].最近,Versteegh等[4]发现蚯蚓的粪便中微小的方解石颗粒 (Earthworm Calcite Granule, ECG) 会记录下周围环境的信息,因此可以作为了解古气候变化的“金钥匙”.ECG在古气候研究领域已引起国际学者的广泛关注,相关成果已在PNAS、Geochimica et Cosmochimica Acta等国际一流刊物上发表[4,5,6,7],成为古气候研究中新的国际前沿交叉学科研究方向.Prud' Homme等[5,6] 利用末次冰期黄土中ECG 的氧同位素(δ18O)和碳同位素(δ13C)重建了土壤及大气的温度和降水量,证实ECG可以作为一个新的古气候指标.同时,ECG也可以为年代学研究提供很好的放射性碳测年材料,其结果与其他一些测年材料 (如木炭、骨骼、植物钙化根系细胞等) 的测年结果可以很好地对比[7,8],如Moine 等[7]对德国莱茵河谷地Nussloch黄土序列中的ECG进行放射性碳同位素测年,结果显示该土壤序列形成于47~20 ka BP,古土壤发育时期与格陵兰冰芯氧同位素记录的间冰阶可以很好地对应. ...
... [5,6] 利用末次冰期黄土中ECG 的氧同位素(δ18O)和碳同位素(δ13C)重建了土壤及大气的温度和降水量,证实ECG可以作为一个新的古气候指标.同时,ECG也可以为年代学研究提供很好的放射性碳测年材料,其结果与其他一些测年材料 (如木炭、骨骼、植物钙化根系细胞等) 的测年结果可以很好地对比[7,8],如Moine 等[7]对德国莱茵河谷地Nussloch黄土序列中的ECG进行放射性碳同位素测年,结果显示该土壤序列形成于47~20 ka BP,古土壤发育时期与格陵兰冰芯氧同位素记录的间冰阶可以很好地对应. ...
... 如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7].Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6).由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度. ...
... 如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7].Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6).由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度. ...
... 在年代学研究中,除了使用放射性14C测年,还可以用铀系测年法对ECG进行测年[4,7,9].例如,Versteegh等[4]通过对英国威尔特郡Silbury Hill遗址中ECG进行U-Th不平衡定年,确定了该遗址形成年龄为(4 670±440 ) a BP,这与碳酸盐颗粒的铀系年龄较一致,表明它们与土壤的形成处于同一时期,确定了该遗址属于新石器时代. ...
... 如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7].Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6).由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度. ...
... Position where the Earthworm Calcite Granule (ECG) is produced within the body of earthworm and morphology features and interior structure of the ECG (modified after reference[6]) (a) The position of calciferous glands in earthworm[11,12]; (b) Scanning Electron Microscopy of an ECG produced by Lumbricus terrestris; (c) Micrograph of one ECG; (d) Thin section of an ECG ...
Origin of calcium carbonate granules found in buried soils and Quaternary deposits
... Position where the Earthworm Calcite Granule (ECG) is produced within the body of earthworm and morphology features and interior structure of the ECG (modified after reference[6]) (a) The position of calciferous glands in earthworm[11,12]; (b) Scanning Electron Microscopy of an ECG produced by Lumbricus terrestris; (c) Micrograph of one ECG; (d) Thin section of an ECG ...
Earthworm activity: A source of potential disturbance of archaeological sediments
Small scale secondary CaCO3 accumulations in selected sections of the European loess belt. Morphological forms and potential for paleoenvironmental reconstruction
Morphology and dynamics of calcium carbonate granules produced by different earthworm species: The 7th international symposium on earthworm ecology· cardiff· wales· 2002
... 如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7].Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6).由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度. ...
... 德国Nussloch P8剖面中ECG的δ18O值推算的土壤和空气温度[22] ...
... Soil and air temperatures inferred from the δ18O values of earthworm calcite granules for profile P8 at Nussloch, Germany[22] ...
Chronometry of pedogenic and stratigraphic events from calcite produced by earthworms
0
2015
Experimental determination of salinity, temperature, growth, and metabolic effects on shell isotope chemistry of mytilus edulis collected from Maine and Greenland
Oxygen isotope fluctuations in a modern north sea oyster (crassostrea gigas) compared with annual variations in seawater temperature: Implications for palaeoclimate studies
Oxygen and carbon stable isotope composition of authigenic carbonates in loess sequences from the carpathian margin and podolia, as a palaeoclimatic record
Influence of the seasonal snow cover on the ground thermal regime: An overview
1
2005
... 如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7].Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6).由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度. ...
Effects of climate on the active layer and permafrost on the north slope of alaska, USA
1
1997
... 如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7].Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6).由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度. ...
1
1967
... 如上所述,蚯蚓排出的方解石颗粒中的碳、氧同位素组成与其生存时期的植被碳同位素、大气降水同位素、温度等要素之间有良好的对应关系,可作为估算年、季降雨量和温度变化的指标[4,5,6,7].Prud'Homme等[22]将取自德国莱茵河谷地区的Nussloch黄土—古土壤序列中的ECG作为一种新的生物气候指标,利用收集的国际原子能机构 (International Atomic Energy Agency, IAEA) 高纬度气象台站气候数据以及Versteegh等[4]与Zhang等[35,36]建立的经验公式,建立起ECG中δ18O值、大气和土壤温度与水循环之间的转换函数,重建的末次冰期时期空气和土壤的绝对温度为10~(12±4)℃ (图6).由于蚯蚓存活的时期是由季节决定的,一般在春、秋季活动最频繁[37],所以该结果反映了一年中温暖时期的气温,而不是年平均温度. ...
Carbon isotope compositions of terrestrial C3 plants as indicators of (paleo)ecology and (paleo)climate
Late Miocene climatic and environmental variations in northern Greece inferred from stable isotope compositions (delta O-18, delta C-13) of equid teeth apatite
Palaeoprecipitation reconstruction by inverse modelling using the isotopic signal of loess organic matter: Application to the Nussloch loess sequence (Rhine valley, Germany)
0
2005
Carbonate rhizoliths in loess and their implications for paleoenvironmental reconstruction revealed by isotopic composition:δ13C ,14C