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Effect of Selected Organic Acids on Cadmium Sorption by Variable- and Permanent-Charge Soils

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Pedosphere 2007年第1期17卷 117-123页

作者： HU Hong-Qing LIU Hua-Liang he ji-zheng HUANG Qiao-Yun Key Laboratory of Subtropical Agriculture Resource and Environment Ministry of Agriculture Huazhong Agricultural University Wuhan 430070 （China） Research Center for Boo-Environment Chinese Academy of Sciences Beijing 100085 （China）

Batch equilibrium experiments were conducted to investigate cadmium （Cd） sorption by two permanent-charge soils, a yellow-cinnamon soil and a yellow-brown soil, and two variable-charge soils, a red soil and a latosol, with addition of selected organic acids （acetate, tartrate, and citrate）. Results showed that with an increase in acetate concentrations from 0 to 3.0 mmol L^-1, Cd sorption percentage by the yellow-cinnamon soil, the yellow-brown soil, and the latosol decreased. The sorption percentage of Cd by the yellow-clnnamon soil and generally the yellow-brown soil （permanent-charge soils） decreased with an increase in tartrate concentration, but increased at low tartrate concentrations for the red soil and the latosol. Curves of percentage of Cd sorption for citrate were similar to those for tartrate. For the variable-charge soils with tartrate and citrate, there were obvious peaks in Cd sorption percentage. These peaks, where organic acids had maximum influence, changed with soil type, and were at a higher organic acid concentration for the variable-charge soils than for the permanent charge soils. Addition of cadmium after tartrate adsorption resulted in higher sorption increase for the varlable-charge soils than permanent-charge soils. When tartrate and Cd solution were added together, sorption of Cd decreased with tartrate concentration for the yellow-brown soil, but increased at low tartrate concentrations and then decreased with tartrate concentration for the red soil and the latosol.

关键词： cadmium sorption organic acids variable- and permanent-charge soils

Progress in Significant Soil Science Fields of China over the Last Three Decades: A Review

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Pedosphere 2011年第1期21卷 1-10页

作者： ZHAO Qi-Guo he ji-zheng YAN Xiao-Yuan ZHANG Bin ZHANG Gan-Lin CAI Zu-Cong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 (China) Key Laboratory of Plant Nutrition and Nutrient Cycling of the Ministry of Agriculture of China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 (China)

Due to continuous decreases in arable land area and continuous population increases,Chinese soil scientists face great challenges in meeting food demands,mitigating adverse environmental impacts,and sustaining or enhancing soil productivity under intensive *** the aim of promoting the application of soil science knowledge,this paper reviews the achievements of Chinese scientists in soil resource use and management,soil fertility,global change mitigation and soil biology over the last 30 *** this period,soil resource science has provided essential support for the use and exploitation of Chinese soil resources,and has itself developed through introduction of new theories such as Soil Taxonomy and new technologies such as remote *** fertility science has contributed to the alleviation and elimination of impeding physical and chemical factors that constrain availability of essential nutrients and water in soils,the understanding of nutrient cycling in agroecosystems,and the increase in nutrient use efficiency for sustainable crop *** soil scientists have contributed to the understanding of the cropland's role in global change,particularly to the understanding of methane and nitrous oxide emission from rice fields and the effect of elevated carbon dioxide and ozone on rice-wheat *** biology research has progressed in biological N fixation,distribution of fauna in Chinese soils,and bioremediation of polluted soils.A new generation of soil scientists has arisen in the last three *** gaps between research and application in these soil science fields are also discussed.

关键词： global change soil biology soil fertility soil resources

Effect of Long-Term Application of Chemical Fertilizers on Microbial Biomass and Functional Diversity of a Black Soil

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Pedosphere 2008年第6期18卷 801-808页

作者： KONG Wei-Dong ZHU Yong-Guan FU Bo-jie HAN Xiao-Zeng ZHANG Lei he ji-zheng Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 （China） Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Harbin 150040 （China） Institute of Microbiology Chinese Academy of Sciences Beijing 100080 （China）

An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to examine the effect of long-term continuous application of chemical fertilizers on microbial biomass and functional diversity of a black soil (Udoll in the USDA Soil Taxonomy) in Northeast China. The soil microbial biomass C ranged between 94 and 145 mg kg-1, with the NK treatment showing a lower biomass; the functional diversity of soil microbial community ranged from 4.13 to 4.25, with an increasing tendency from control to double-fertilizer treatments, and to triple-fertilizer treatments. The soil microbial biomass, and the microbial functional diversity and evenness did not show any significant differences among the different fertilizer treatments including control, suggesting that the long-term application of chemical fertilization would not result in significant changes in the microbial characteristics of the black soil.

关键词： Biolog black soil chemical fertilizer microbial biomass microbial functional diversity

1.4-nm Intergrade Mineral in Soils of Snbtropical China:A Review

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Pedosphere 1995年第2期5卷 151-156页

作者： he ji-zheng XU FENG-LIN LIU FAN and LI XUE-YUAN(Huazhong Agricultural University, W’uhan.430070 (China)

This paper is a review of some advances in the studies on 1.4-nm intergrade mineral of soils in sub-tropical China. 1) 1.4-nm intergrade mineral occurs ubiquitously in soils of subtropical China. The 1.4-nmrnineral in red soil and yellow soil is mainly 1.4-nm intergrade mineral, and in acidic yellow-brown soil (pHher with vermiculite. The distribution and thecontent of 1 .4-nm intergrade mineral in the mountain soils are more widespread and higher than those of thecorresponding soils in horizontal zone. 2) The interlayer material of 1.4-nin intergrade mineral ui these soilsappears to be hydroxy-Al polymers instead of hydroxy-Fe, proto-imogolite or kaolin-like material. There isa significant positive correlation between Al amount extracted from the soil with sodium citrate after DCBextraction and pH value of the citrate solution after the extraction. The citrate can also extract a certainamount of silicon from the soil, but the silicon may not come from interlayer of 1.4-nm intergrade mineral.3) It was seldom studied that either vermiculite or smectite did the natural 1.4-nm intergrade mineral comefrom in soil, or it was commonly thought to come from vermiculite. A recent report has revealed that itcan come from smectite. There are some different behaviors between the 1.4-nm intergrade mineral derivedfrom vermiculite and that from smectite. For example, they exert different influences on the formation ofgibbsite. The 1.4-nm intergrade mineral derived from smectite may promote the formation of gibbsite in theyellow soil. 4) The type of 1.4-nm minerals in soils. i.e., vermiculite or 1.4-nm intergrade mineral, may besignificant to soil properties, such as soil acidity, exchangeable Al, electric charge aiiiount and specifi

关键词： interlayer material 1.4-nm intergrade mineral subtropical soil surface property

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土壤微生物生物地理学研究进展

生态学报 2008年第11期28卷 5571-5582页

作者：贺纪正葛源城市与区域生态国家重点实验室中国科学院生态环境研究中心北京100085 中国科学院研究生院北京100049

生物地理学是研究生物(包括种群、群落等不同层次)地理分布格局及成因的一门交叉学科。微生物生物地理学的研究长期滞后于宏生物地理学。鉴于土壤微生物在调控生物地球化学过程和维持生态系统功能方面的重要作用,对其空间分布格局及形... 详细信息

生物地理学是研究生物(包括种群、群落等不同层次)地理分布格局及成因的一门交叉学科。微生物生物地理学的研究长期滞后于宏生物地理学。鉴于土壤微生物在调控生物地球化学过程和维持生态系统功能方面的重要作用,对其空间分布格局及形成机制的认识具有十分重要的理论和实际意义。随着分子生物学技术的发展,对微生物多样性的认知日益深入。越来越多的证据表明,土壤微生物群落结构和多样性具有一定的时空分布格局,从而对微生物全球性随机分布的传统观点提出了挑战。对当前土壤微生物生物地理学研究中的一些概念性问题,如微生物物种的定义、微生物多样性的定量测度、对微生物全球性随机分布的争论等,进行了系统评述;以微生物种-面积关系和距离-衰减关系为例对当前最新的土壤微生物生物地理学研究成果进行总结,并初步探讨了土壤微生物群落的地带性分布问题;在传统生物地理学理论的指导下,提出了一个可用于验证土壤微生物空间分布格局形成和机制维持的简单研究框架。这些对今后土壤微生物生物地理学的研究有一定借鉴和指导意义。

关键词：微生物生物地理学微生物多样性群落结构种-面积关系距离-衰减关系理论

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氨氧化微生物生态学与氮循环研究进展

生态学报 2009年第1期29卷 406-415页

作者：贺纪正张丽梅城市与区域生态国家重点实验室中国科学院生态环境研究中心北京100085

氮的生物地球化学循环主要由微生物驱动,除固氮作用、硝化作用、反硝化作用和氨化作用外,近年还发现厌氧氨氧化是微生物参与氮循环的一个重要过程。同时,随着宏基因组学等分子生物技术的快速发展和应用,参与氮循环的新的微生物类群——... 详细信息

氮的生物地球化学循环主要由微生物驱动,除固氮作用、硝化作用、反硝化作用和氨化作用外,近年还发现厌氧氨氧化是微生物参与氮循环的一个重要过程。同时,随着宏基因组学等分子生物技术的快速发展和应用,参与氮循环的新的微生物类群——氨氧化古菌也逐渐被发现。这两个重要的发现大大改变了过去人们对氮循环的认识,就近年有关厌氧氨氧化细菌、氨氧化古菌和氨氧化细菌的生态学研究进展作一简要综述。

关键词：氮循环氨氧化作用厌氧氨氧化作用中温泉古菌氨氧化细菌

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极端环境下嗜热酸甲烷营养细菌研究进展

生态学报 2009年第7期29卷 3864-3871页

作者：郑勇郑袁明张丽梅贺纪正中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 中国科学院研究生院北京100049

甲烷营养细菌能够将温室气体甲烷(CH4)转化为CO2或生物质,在碳生物地球化学循环及缓解由温室气体导致的全球气候变化方面发挥着重要的作用。甲烷营养细菌生存的条件范围较为广泛,但在中性pH(5～8)和中温(20～35℃)范围内生长最佳。系统... 详细信息

甲烷营养细菌能够将温室气体甲烷(CH4)转化为CO2或生物质,在碳生物地球化学循环及缓解由温室气体导致的全球气候变化方面发挥着重要的作用。甲烷营养细菌生存的条件范围较为广泛,但在中性pH(5～8)和中温(20～35℃)范围内生长最佳。系统进化分析认为,它们均属于γ-或α-变形菌门(Proteobacteria)。最近3项独立完成的研究从极端热酸(pH接近1,温度高于50℃)环境中分离获得了具有甲烷氧化(营养)功能的微生物,经鉴定均属于疣微菌门(Verrucomicrobia)。这些全新的、不同于以往的研究结果不仅是对现有关于甲烷营养细菌生态学认知的进一步拓展,同时也暗示着可能存在着新型的、由微生物介导的CH4氧化途径与机制。因此,特就极端环境中嗜热嗜酸甲烷营养细菌的最新研究进展作一概述。

关键词：甲烷营养细菌极端环境基因组分析代谢途径疣微菌门

丛枝菌根真菌对大气CO_(2)浓度升高和增温响应研究进展

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应用生态学报 2022年第6期33卷 1709-1718页

作者：宋鸽王全成郑勇贺纪正福建师范大学湿润亚热带生态地理过程教育部重点实验室福州350007 福建师范大学地理科学学院福州350007 福建三明森林生态系统国家野外科学观测研究站福建三明365002

全球变化深刻影响着陆地生态系统生物多样性及生态功能。丛枝菌根(AM)真菌可与绝大多数陆生植物根系形成互惠共生体,在协助宿主养分吸收、促进植物生长、维持植物多样性等方面发挥着重要作用。本文主要分析了大气CO_(2)浓度升高(eCO_(2)... 详细信息

全球变化深刻影响着陆地生态系统生物多样性及生态功能。丛枝菌根(AM)真菌可与绝大多数陆生植物根系形成互惠共生体,在协助宿主养分吸收、促进植物生长、维持植物多样性等方面发挥着重要作用。本文主要分析了大气CO_(2)浓度升高(eCO_(2))和增温对森林和草地生态系统AM真菌群落组成及其功能的影响。eCO_(2)主要通过影响宿主植物、土壤碳(C)输入等方式间接影响AM真菌,可增加AM真菌的多度和活性,影响AM真菌的多样性与群落组成。增温可直接或间接地(通过宿主植物和土壤途径)影响AM真菌,显著改变森林土壤AM真菌的群落组成,但对草地土壤AM真菌群落组成的影响尚无定论。我们提出了当前研究中存在的主要问题及未来应重点关注的内容。本文旨在明晰AM真菌对eCO_(2)和增温的响应和适应,增进对AM真菌介导的土壤生态功能的认识,为利用AM真菌缓解全球变化、增强土壤功能的韧性和全球变化的生态系统适应性提供依据。

关键词：丛枝菌根真菌群落组成多样性二氧化碳浓度升高全球变化森林生态系统

Effect of cholesterol metabolism on hepatolithiasis

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World Journal of Gastroenterology 2025年第1期31卷 157-162页

作者： Lin zheng Zi-Yu Ye Jun-ji Ma Department of Gastroenterology The Second Hospital of Hebei Medical UniversityHebei Key Laboratory of GastroenterologyHebei Institute of GastroenterologyHebei Clinical Research Center for Digestive DiseasesNo.215 Heping West RoadShijiazhuang 050000Hebei ProvinceChina

Surgical intervention is currently the primary treatment for hepatolithiasis;how-ever,some patients still experience residual stones and high recurrence rates after *** metabolism seems to play an important role in hepatoli-thiasis pathogenesis.A high cholesterol diet is one of the significant reasons for the increasing incidence of ***,regular diet and appropriate medical intervention are crucial measures to prevent hepatolithiasis and reduce recurrence rate after *** dietary cholesterol and drugs that increase cholesterol stone solubility are key therapeutic approaches in treating *** article discusses the cholesterol metabolic pathways related to the pathogenesis of hepatolithiasis,as well as food intake and targeted therapeutic drugs.

关键词： hepatolithiasis Cholesterol metabolism High-fat diet 3-hydroxy-3-methylglutaryl-coenzyme A reductase Interlobular bile duct