【作者】 孙艳丽；

【导师】 马建华；

【作者基本信息】 河南大学 ， 自然地理学， 2011， 博士

【摘要】 随着工业化在大多数国家的普及,城市化进程在全球范围内迅速展开,长期而持续的城市用地扩张导致土地利用方式发生了显著改变,这种改变会对土壤的性质产生深刻影响。国内外对城市土壤的早期研究主要以土壤肥力为中心进行,初步探讨了城市土壤的性质、化学组成等方面。之后,随着全球环境形势的日益严峻,城市土壤碳储存开始受到关注。当前国内外城市土壤有机碳研究主要侧重于绿地土壤表层与次表层的养分特征分析,对有机碳的垂直分布研究较少;缺乏对有机碳时间变化规律的分析;研究对象集中于植被覆盖下的绿地土壤,对无植被覆盖下土壤有机碳的研究十分薄弱;对有机碳组分的分析力度不够,及缺乏对有机碳组分间相互关系的探讨。因而,开展全面而深入的城市土壤有机碳研究,了解城市化过程对土壤有机碳库的影响是十分必要的。本研究以具有2700多年建城史的开封市为研究对象,在调查采样和实验室分析的基础上,从土壤有机碳组成、储量、空间分布和时间变化几个方面开展较系统的城市土壤有机碳分析,以丰富城市土壤有机碳库基础数据信息和城市土壤有机碳研究案例,为城市土壤的科学管理和城市生态系统的可持续发展提供依据。研究中布设了绿地标准土壤剖面样点（25个）、非绿地土壤剖面样点（8个）和绿地表层样点（112个）3种样点类型,共采集绿地土壤标准剖面样品91个,非绿地土壤剖面土壤样品79个,表层绿地土壤样品112个。对土壤样品分别进行了基本理化性质、有机碳、腐殖质碳、轻组有机碳、颗粒有机碳、易氧化有机碳、水溶性有机碳和黑碳的测定。全文共包括九章,分属五大部分:第一部分是绪论（第一章）,主要包括选题背景和国内外城市土壤有机碳研究综述;当前城市土壤有机碳研究中存在的问题;今后的研究趋势;本研究的主要内容及研究意义。第二部分是材料与方法（第二章）,主要包括研究区的自然、社会经济和环境污染概况;土壤样点布设及样品采集;有关试验项目的试验方法;数据处理的主要方法和论文的技术路线。第三部分是开封城市土壤有机碳组成、储量及空间分布（第三、四、五、六章）,主要包括土壤有机碳、活性有机碳、腐殖质碳（胡敏酸碳、富里酸碳、胡敏素碳）和黑碳的含量分析、功能区差异分析、水平和垂直分布特征分析。第四部分是开封城市土壤有机碳的时间变化和城—郊梯度变化（第七章和第八章）。主要包括城市土壤表层有机碳和剖面有机碳的纵向时间变化分析;表层有机碳和表层活性有机碳的横向时间变化分析;土壤有机碳和组分有机碳的城郊区域差异与城—郊梯度变化分析。第五部分是结论与讨论（第九章）,主要包括本研究的基本结论,及研究中存在的不足和今后的研究展望。通过研究,得出如下主要结论:（1）城市绿地土壤表层有机碳含量与密度均高于郊区土壤和非绿地土壤,剖面有机碳密度是郊区土壤的1.15倍。绿地土壤表层活性有机碳贮存量高于非绿地土壤;土壤活性有机碳中的颗粒有机碳（POC）和轻组有机碳（LFOC）均高于郊区土壤,易氧化有机碳（ROC）和水溶性有机碳（WSOC）则均低于郊区土壤。绿地土壤表层腐殖质碳贮存低于郊区土壤,其在有机碳中的比例比郊区土壤低10.76%。土壤胡敏酸含碳量和胡敏素含碳量均高于郊区土壤,富里酸含碳量则比郊区土壤低31%。城市土壤胡富比（HA/FA）均值比郊区土壤高0.09,而胡敏酸的E4/E6均值比郊区土壤低0.03。城市土壤表层黑碳含量是郊区土壤的1.34倍。（2）城市不同功能区内土壤有机碳、活性有机碳、腐殖质碳和黑碳的贮存均呈明显差异。表层有机碳含量与密度均为:工业区>行政区>道路邻近区>居民区>文教区>休闲区。剖面有机碳密度为:文教区>道路临近区>工业区>行政/居民区>休闲区。活性有机碳的功能区差异中,以工业区和行政区土壤POC、ROC、LFOC的贮存最多,文教区和休闲区的贮存最少;休闲区土壤WSOC的贮存最多,工业区和行政区的贮存最少。土壤表层腐殖质碳及其组分的碳贮存均以工业区为最多,休闲区最少。土壤腐殖质的聚合程度（HA/FA）则以休闲区为最好,工业区最差。土壤胡敏酸的芳构化度（E4/E6）为:文教区<工业区<行政区<道路临近区。土壤表层黑碳的功能区差异为:工业区>行政区>文教区>道路临近区>休闲区>居民区。（3）非绿地土壤中裸地土壤的有机碳贮存优于建筑物及道路覆盖下土壤。土壤表层POC、ROC、LFOC含量与密度均为裸地土壤>建筑物覆盖土壤>道路覆盖土壤;土壤表层WSOC含量为裸地土壤>建筑物覆盖土壤>道路覆盖土壤,WSOC密度则以道路覆盖土壤的最高,分别是裸地土壤和建筑物覆盖土壤的1.33和1.50倍。（4）绿地土壤有机碳、活性有机碳、腐殖质碳呈现出不同的水平分布特征。土壤有机碳由开封市东部区域向西北区域呈环状递减。土壤POC呈带状延伸,且沿东南–西北向逐渐降低;ROC呈由南向北带状递减的水平分布格局;WSOC的空间分布形态为斑块状,分别在城市东南部、西部及其以西的郊区、东南郊区出现三个高值区;LFOC呈由东向西逐渐递减的水平分布格局。腐殖质碳为由东向西和由城市中心向南、向北两方向递减。（5）绿地土壤有机碳、腐殖质碳、活性有机碳的垂直分布基本都表现为随深度的增加而降低,具有一定的表聚性。约40%～60%的有机碳贮存在0³0cm的层段内,该层段内LFOC、POC和ROC贮存量分别占剖面总量的46.59%、56.41%和50.31%;土壤WSOC在0³0 cm和30⁶0 cm两个层段内的贮存量占剖面总量的百分比相近,分别为30.62%和30.08%。腐殖质组分随深度增加而垂向递减的变化规律由强至弱为:胡敏素碳>胡敏酸碳>富里酸碳。土壤HA/FA沿剖面的垂向变化无特定规律。土壤胡敏酸E4/E6值随土壤深度的增加呈幂函数下降（R2=0.448⁰.988,p<0.05）。非绿地土壤有机碳、黑碳也呈现出随深度增加而降低的垂向变化。（6）在纵向时间对比中,土壤表层有机碳含量、密度和剖面有机碳密度均随时间增长有所增加,增幅分别在0.99～28.19 g kg–1、0.12～3.39 kg m^-2和0.39～7.59 kg m–2之间。在横向时间对比中,I时段（20世纪初以前）的土壤表层有机碳含量、密度分别是Ⅱ时段（20世纪初之后）土壤的1.19倍（p>0.05）和1.08倍（p>0.05）。I时段土壤的LFOC、POC、ROC、腐殖质碳含量分别为Ⅱ时段土壤的1.15、1.35、1.44和1.16倍;土壤WSOC的横向差异不大;Ⅰ时段土壤的HA/FA低于Ⅱ时段土壤。（7）土壤有机碳的城—郊梯度变化为:表层有机碳与剖面有机碳在各梯度线上均为城区土壤高于郊区土壤,但老城区、新城区、郊区间的差异在4条梯度线上各异;随着离城市中心距离的增加,有机碳贮存减少。土壤腐殖质碳沿城—郊的梯度变化无可循规律,但其在有机碳中所占的比例表现为郊区>老城区>新城区,且随离城市中心距离的增加而增大。土壤HA/FA随离城市中心距离的增加无显著变化。土壤胡敏酸E4/E6总体表现为城区土壤低于郊区土壤。城区土壤LFOC、POC、BC的贮存总体上高于郊区土壤,3种组分有机碳均随离城市中心距离的增加而降低。城区土壤WSOC贮存低于郊区土壤,表现为随离城市中心距离的增加而增多。土壤ROC在城郊区域间无明显差异,沿城—郊梯度线的变化情况也较复杂,在市区北部梯度线上其与距离间呈低度线性负相关;在南部梯度线上受距离因子的影响则很微弱。城区土壤黑碳含量高于郊区土壤,随离城市中心距离的增加土壤黑碳表现出降低的变化趋势。更多还原

【Abstract】 With the industrialization in most countries, Urbanization carried out in global area. The long–term and continuous land expansion changed the land use and land cover, what had profound influence on soil organic carbon. The early researches of the urban soils focused on the fertility, including the characteristics and chemical components. Afterwards, with the serious situation of global environment, soil organic carbon of urban soils were concerned. The current researches concerned on the topsoil and sub–surface layer of soil, ignoring the vertical distribution of soil organic carbon; concerned on the soil covered by vegetation, ignoring the soil with no vegetation cover; concerned on the total organic carbon, ignoring the components; and the researches on temporal variation of soil organic carbon were not enough. Therefore, to be familiar with the influence of urbanization on soil organic carbon depended on deeper and wider researches. Taking Kaifeng city which had about 2700 yrs city–building history as the research object, the components, storage and temporal–spatial variations of soil organic carbon were studied based on the sampling and experiment. 25 norm soil profiles in greenlands, 8 soil profiles in lands with non–vegetation cover and 112 topsoil samples were set, collecting 91 profile samples in greenlands, 79 profile samples with non–vegetation cover and 112 topsoil samples. The samples were experimented on physical–chemical property, organic carbon, humus, light fraction organic carbon, Particulate organic carbon, Readily oxidizable carbon, water–soluble organic carbon and black carbon. There were nine chapters in the paper, including five sections:The first section was introduction（the first chapter）, including the background, survey, existing problems, trend of urban soil organic carbon; main contents and significance of this paper.The second section was material and methods（the second chapter）, including natural and socioeconomic status , environmental pollution situation; setting and collection of soil samples; experimental methods of items; data processing method; technical route of this paper.The third section was the components, storage and temporal–spatial variations of urban soils（the third, fourth, fifth and sixth chapter）, including storage, difference among functional districts, horizontal and vertical distribution of soil organic carbon, active organic carbon, carbon in humus（carbon in humic acid, fulvic acid and humin） and black carbon. The fourth section was the temporal variations and variations along transaction line from urban areas to suburbs（the seventh and eighth chapter）, including the difference of soil organic carbon in topsoil and profile along the time; the difference of soil organic carbon and active organic carbon in topsoil among different–aging greenlands; variations of soil organic carbon and the components between urban areas and suburbs, and along the transaction line from the center of urban area to suburbs.The fifth section was conclusion and discussion（the ninth chapter）, including the conclusion, deficiency and prospect of this research.The main results were as follows:（1）The contents and densities of soil organic carbon in topsoil of urban areas were higher than soils with non–vegetation cover and soils in suburbs. Urban soils had 1.15–fold more densities of soil organic carbon（SOCD） in profiles than suburbs. The storage of soil organic carbon in greenlands was higher than lands with non–vegetation cover; the values of POC and LFOC in urban soils were higher than that in suburbs, the situation of ROC and WSOC were the opposite. The storage of humus in urban soils was lower than that in suburbs, and the percentage of carbon in humus in total organic carbon in urban soils was lower than that in suburbs by 10.76%. The contents of carbon in humic acid and humin were higher in urban soils than that in suburbs, the contents of carbon in fulvic acid in urban soils was lower than that in suburbs by 31%. The value of HA/FA in urban soils was 0.09 higher than that in suburbs. The value of E4/E6 in urban soils was 0.03 lower than that in suburbs. The urban soils had 1.34–fold more BC in topsoil than suburbs.（2） The storage of soil organic carbon, active organic carbon, carbon in humus and BC were different among functional districts. The order of the contents and densities of topsoil were all industrial district > administrative district> traffic district > residential district > cultural/educational district >recreational district. The SOCD in profile followed the order of cultural/educational district> traffic district >industrial district > residential/administrative district > recreational district. Industrial district and administrative district had the higher storage of POC, ROC and LFOC; cultural/educational district and recreational district had the lower storage of them. However, the storage of WSOC in recreational district was the highest among functional districts, and the storage WSOC in industrial district and administrative district were lower. The storage of carbon in humus and its components were the highest in industrial districts, the lowest in recreational district. The value of HA/FA was the highest in recreational district, the lowest in industrial districts. The order of the value of E4/E6 was cultural/educational district <industrial district< administrative district< traffic district. BC in topsoil of urban soils followed the order of industrial district> administrative district> cultural/educational district> traffic district> recreational district> residential district.（3） The storage of soil organic carbon in bare land was higher than that in land with building and road cover. The contents and densities of POC, ROC and LFOC in topsoil all followed the orders of bare lands> lands covered by buildings> land covered by road. The content of WSOC followed the order of bare lands> lands covered by buildings> land covered by road. However, the soils in land covered by road had 1.33–fold and 1.50–fold more density of WSOC than bare lands and lands covered by buildings, respectively.（4） The horizontal distribution of soil organic carbon, active organic carbon and carbon in humus were different. The shape of horizontal distribution of soil organic carbon was annular, and the contents declined from the east area to northwestern area. The distribution of POC took on a string shape, and the contents declined from southeastern area to northwestern area. The content of ROC declined from the southern area to northern area. The shape of WSOC’s distribution was speckle, with three high value centers in southeastern area and western area in urban area, western area and southeastern area in suburbs, respectively. The value of LFOC declined from eastern area to western area. The value of carbon in humus declined from eastern area to western area, and from the center of urban area to northern area, and to southern area, respectively.（5） The contents of soil organic carbon, carbon in humus and active organic carbon in greenlands declined with the depth. They were mainly distributed within the scope of 0³0cm, with about 40⁶0% of soil organic carbon, 46.59% of LFOC, 56.41% of POC, 50.31% of ROC. The storage of WSOC in the scope of 0³0cm and 30⁶0cm were closed, with the percentages of 30.62% and 30.08%, respectively. The components of humus declined with the depth, and the order of regularity was carbon in humin>carbon in humic acid> fulvic acid. There was no obvious variation of HA/FA in vertical distribution. The vertical distribution of E4/E6 followed the regularity of power function（R²=0.448⁰.988,p<0.05）. The soil organic carbon and BC in topsoil of lands covered with no vegetation declined with the depth.（6） The contents and densities in topsoil and densities in profile increased with the time, with the increasing range of 0.99～28.19 g kg^–1, 0.12～3.39 kg m^–2 and 0.39～7.59 kg m^–2, respectively. Period I（before the early of 20th century） had 1.19–fold more content of soil organic carbon and 1.08–fold more SOCD in topsoil than period II（after the early of 20th century）, respectively. The contents of LFOC, POC, ROC and carbon in humus of period I were 1.15, 1.35, 1.44 and 1.16 times more than periodⅡ, respectively. There was no obvious rise of WSOC. The value of HA/FA of periodⅠwas lower than periodⅡ.（7） The storage of soil organic carbon in topsoil and in profile in urban area were higher than that in suburbs along the transaction line. The storage of soil organic carbon declined from the center of urban area to suburbs. There was obvious variation of the contents of carbon in humus along the transaction line. however, the percentage of it in total organic carbon was followed the order suburbs>old urban area> new urban area, and the percentage increased along the transaction line from the center of urban area to suburbs. There was no obvious variation of HA/FA in this line. The value of E4/E6 in urban area was higher than that in suburbs. The storage of LFOC, POC and BC in urban area were higher than that in suburbs, and they all declined from the center of city to suburbs. The storage of WSOC in urban area was lower than that in suburbs, increasing with the distance. The storage of ROC in urban area was similar to that in suburbs, and took on a complicated variation in transaction line. The contents of BC in urban area was higher than that in suburbs, and it declined with the distance.更多还原