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Geochemical Implication of Rare Earth Elements in Process of Soil Development

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Journal of Rare Earths 2001年第1期19卷 57-62页

作者：黄成敏龚子同 Sichuan Univ Coll Environm Sci & Engn Chengdu 610065 Peoples R China Chinese Acad Sci Inst Soil Sci Nanjing 210008 Peoples R China

The geochemical characteristics and behavior of rare earth elements (REE) in soils developed on the basalts in the northern part of Hainan Island erupted in different time were studied as well as the REE partition in the soil-formation process and its implication on soil development degree. The results show that the total REE content in soils is correlative with soil age significantly and can be selected as the index to show soil evolution. With the soil developing intensively, light rare earth elements (LREE) gain and heavy rare earth elements (HREE) lose. The trends of positive Ce-anomaly and negative Eu-anomaly are remarkable with soil development.

关键词： rare earths soil geochemistry basalt partition

Grain Size Evidence of Multiple Origins of Red Clays in the Jinhua-Quzhou Basin, South China

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Pedosphere 2013年第5期23卷 686-695页

作者： LI Jian-Wu YE Wei ZHANG Gan-Lin ZHU Li-Dong JIANG Yong-Jian gong zi-tong Zhejiang Provincial Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration Zhejiang A & F University State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Geography Process Lab Zhejiang Normal University Nanjing Institute of Geography and Limnology Chinese Academy of Sciences

Six typical red clay profiles were sampled from Tangxi （TX）, Langyaz （LYZ）, South Shangshanwen （SSW）, Xianqiao （XQ）, Qijian （Q J） and Huhaitang （HHT） of Jinhua-Quzhou Basin, Zhejiang Province of China to evaluate the characteristics of grain size composition, distribution and parameters of red clays and to reveal the origin of red clays and interpret possible implications for paleoclimate in subtropical China. The results showed that red clays in TX, LYZ and SSW were fine and uniform, with no 〉 2 mm gravels and little 〉 63μm fraction. They had a high content of 10-50 μm fraction, so-called ＂basic dust fraction＂, and showed unimodal distributions, which were very comparable to those of the Xiashu Loess in southeastern China and the loess in North China. All these features reflected marked aeolian characteristics of the red clays in these areas. Red clays in XQ and QJ were much coarser than those in TjjX, LYZ and SSW, with high contents of 〉 63μm fraction and even containing 〉 2 mm gravels in some layers. The grain size distribution patterns showed significantly progressive trends from the lower profile to the upmost layer and could not be compared with those of the loess in North China or the Xiashu Loess, implying they might be derived from underlying parent rocks and had some inherited properties from bedrock. Red clays in HHT had high contents of 〉 63μm fraetion and contain many 〉 2 mm gravels in each layer. The grain size frequency curves showed multiple-peaks and some abrupt variations were also observed on the profile, revealing its alluvial or diluvial origin in HHT. The multiple origins of red clays reflected the diversity and complexity of the Quaternary environment in South China. It can be concluded that grain size is an effective proxy indicator for the origin of most deposits.

关键词： aeolian characteristics grain size distribution loess paleoclimate Quaternary

Soil degradation: a global problem endangering sustainable development

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Journal of Geographical Sciences 2002年第2期12卷 120-129页

作者： Chen Jie Chen Jing-zhang Tan Man-zhi gong zi-tong CAS Institute of Soil Science Nanjing China (GRID:grid.9227.e) (ISNI:***)

Soil degradation, defined as lowering and losing of soil functions, is becoming more and more serious worldwide in recent decades, and poses a threat to agricultural production and terrestrial ecosystem. It is estimated that nearly 2 billion ha of soil resources in the world have been degraded, namely approximately 22% of the total cropland, pasture, forest, and woodland. Globally, soil erosion, chemical deterioration and physical degradation are the important parts amongst various types of soil degradation. As a natural process, soil degradation can be enhanced or dampened by a variety of human activities such as inappropriate agricultural management, overgrazing, deforestation, etc. Degraded soil means less food. As a result of soil degradation, it is estimated that about 11.9-13.4% of the global agricultural supply has been lost in the past five decades. Besides, soil degradation is also associated with off-site problems of sedimentation, climate change, watershed functions, and changes in natural habitats leading to loss of genetic stock and biodiversity. Therefore, it is essential to combat soil degradation at different levels and scales worldwide, not only for food security and ecological health, but also for the guarantee of global sustainable development.

关键词： soil soil degradation erosion food security sustainable development

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中日土壤工作者学术交流亲历

土壤通报 2022年第6期53卷 1506-1512页

作者：龚子同中国科学院南京土壤研究所江苏南京210008

中日两国是一衣带水的近邻,中日友好源远流长,现代土壤学两国也交流颇丰。我作为一个土壤工作者,从1978年开始多次访日,有幸参与土壤学相关领域学术交流,包括参加中国科学院农业科学考察团,出席在日本京都举办的第14届国际土壤学大会和... 详细信息

中日两国是一衣带水的近邻,中日友好源远流长,现代土壤学两国也交流颇丰。我作为一个土壤工作者,从1978年开始多次访日,有幸参与土壤学相关领域学术交流,包括参加中国科学院农业科学考察团,出席在日本京都举办的第14届国际土壤学大会和东亚、东南亚土壤联合会(ESAFS)会议,与日本知名土壤学家谈合作,协助出版日文版《中国土壤》以及中日两国土壤学家互访等。现将作者的经历和体会进行简要梳理。

关键词：土壤学家学术交流互利共赢

Pedogeochemical Environments and Peoples Health in China

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Pedosphere 1992年第1期2卷 71-77页

作者： gong zi-tong and LUO GUO-BAOInstitute of Soil Science, Academia Sinica, and Laboratory of Material Cycling in Pedosphere, Academia Sinica, P.O. Box 821, Nanjing 210008 (China)

It has long been recognized that pedogeochemistry is closely related with human health. Based on analytical data, the weathering or soil forming processes fall into four stages and China is divided into four geochemical regions: saline soil region, carbonate soil region, siallitic soil region and ferrallitic soil region. Moreover, some endemic diseases in relation to the deficit or excess of some elements are discussed in the viewpoint of pedogeochemistry.

关键词： endemic diseases human health pedogeochemistry regionalization

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古红土的发育与演变

海洋地质与第四纪地质 2000年第3期20卷 37-42页

作者：刘良梧龚子同中国科学院土壤研究所南京210008

分布于江南丘陵地的第四纪红色粘土 ,通常由均质红土层、网纹层和砾石层所构成 ,它是第四纪初期的沉积物 ,但在一定程度上又具有成土作用的特征 ,故称为古红土。深厚的红色风化壳、酸性和高度富铝化是古红土的特点 ,而古红土上发育的红... 详细信息

分布于江南丘陵地的第四纪红色粘土 ,通常由均质红土层、网纹层和砾石层所构成 ,它是第四纪初期的沉积物 ,但在一定程度上又具有成土作用的特征 ,故称为古红土。深厚的红色风化壳、酸性和高度富铝化是古红土的特点 ,而古红土上发育的红壤既继承、保留了古红土的原有特征 ,又在生物作用和人为活动共同作用下形成生物富集的、表层复硅的、高度风化、发育的特征。因此 ,具有昔日和现在环境双重特征的地表红壤是由古红土发育、演变而成的典型残余土壤。

关键词：古红土红壤土壤演变华南

水耕人为土某些氧化还原形态特征的微结构和形成机理

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土壤学报 2001年第1期38卷 10-16页

作者：张甘霖龚子同中国科学院南京土壤研究所南京210008

结合微形态观察和特征微区化学成分的电子能谱测定，对水耕人为土几种典型的氧化还原形态特征的结构进行了解析，并在此基础上提出了它们的形成机理。结果表明，根孔／裂隙淀积铁质胶膜形成于还原亚铁离子在根孔或裂隙面的氧化富集，该... 详细信息

结合微形态观察和特征微区化学成分的电子能谱测定，对水耕人为土几种典型的氧化还原形态特征的结构进行了解析，并在此基础上提出了它们的形成机理。结果表明，根孔／裂隙淀积铁质胶膜形成于还原亚铁离子在根孔或裂隙面的氧化富集，该过程是Fe2＋吸附于铝硅酸盐粘粒表面被氧化；根际铁质同心圆的形成涉及反应—转移—反馈的自组织过程，导致条带状富铁与贫铁区域的形成；淋失胶膜可分为铁锰淋失胶膜和粘粒淋失膜（淋余膜），二者在微结构和化学成分上有明显不同，后者不仅铁锰的淋失更甚，而且伴随铝硅酸盐粘粒的分解。

关键词：水耕人为土氧化还原形态特征微形态形成机理自组织

关于土壤中“化学定时炸弹”及其触爆因素的探讨

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地球科学进展 1998年第2期13卷 184-191页

作者：龚子同黄标中国科学院南京土壤研究所

运用目前环境科学研究中较为流行的“化学定时炸弹”的概念，详细分析了我国土壤中可能的“化学定时炸弹”。认为土壤中存在着地带性和泛地带性的“化学定时炸弹”，地带性的包括土壤盐渍化、土壤酸化等；泛地带性的包括施肥造成的、工... 详细信息

运用目前环境科学研究中较为流行的“化学定时炸弹”的概念，详细分析了我国土壤中可能的“化学定时炸弹”。认为土壤中存在着地带性和泛地带性的“化学定时炸弹”，地带性的包括土壤盐渍化、土壤酸化等；泛地带性的包括施肥造成的、工业污染造成的及特殊成土作用形成的“化学定时炸弹”。同时，探讨了导致土壤中这些“化学定时炸弹”内在和外在的可能触爆因素。提出了今后开展该领域宏观和微观研究的方向和建议。

关键词：土壤化学定时炸弹触爆因素环境化学土壤化学

新世纪的土壤地理学教程——评李天杰等著《土壤地理学》(第3版)

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土壤 2005年第1期37卷 109-111页

作者：龚子同张甘霖中国科学院南京土壤研究所南京210008

这是对高等教育出版社新近出版的、由李天杰教授等编著的《土壤地理学》一书的评述,指出其主要特点和意义,认为这是一本有时代特点的好的教科书。

关键词：土壤形成土壤分类土壤地理