北京地区不同土纲典型剖面的土壤微形态特征

以北京地区不同土纲典型剖面为例,通过观察土壤薄片,利用ENVI图像统计分析功能,从土壤微结构、粗骨颗粒、土壤形成物与孔隙几个方面研究其微形态特征。结果表明:北京地区不同土纲典型剖面土壤之间微形态差异明显。淋溶土典型剖面土壤发育完全,Bt层常见到黏粒淀积胶膜;雏形土与新成土土壤微结构发育程度较低,没有淀积黏粒存在,但雏形土形成了B层,存在孔洞状结构,钙积现象明显,土壤发育较新成土成熟。人为土明显表现出大量人类活动的痕迹,侵入物、动植物遗迹多见,土壤发育最为成熟。     

金衢盆地红色和紫色砂页岩发育土壤的特征和分类

本文研究了金衢盆地红色砂页岩和紫色砂页岩发育土壤的诊断层和诊断特性 ,根据中国土壤系统分类 (修订方案 ) ,把供试土壤分为 2个土纲、2个亚纲、4个土类 ,续分有石灰紫色湿润雏形土、石质铝质湿润雏形土、石灰紫色正常新成土、酸性紫色正常新成土、普通紫色正常新成土、普通红色正常新成土 6个亚类 ,并对它们的基层分类单元进行了探讨     

高寒地区寒冻雏形土的持水特性

讨论了高寒地区寒冻雏形土两个主要土类草毡寒冻雏形土和暗沃寒冻雏形土的持水特性及影响因子。寒冻雏形土具有较高的持水能力，共植物根系分布层饱和含水量为７９．８－１４３．７％，田间持水量可达３３．７－９９．６％，且暗沃寒冻雏形土的持水能力高于草毡寒冻雏形土。     

秦岭北坡土壤发生特性与系统分类

根据野外调查资料和典型土壤剖面理化性质 ,包括室内化验数据综合分析表明 :秦岭北坡土壤的主要发生特性随海拔高度呈有规律的变化 ,依照《中国土壤系统分类 (修订方案 )》检索 ,土壤垂直带谱结构为 :土垫旱耕人为土—简育干润淋溶土—简育湿润淋溶土—酸性湿润雏形土—暗沃寒冻雏形土—暗瘠寒冻雏形土     

渝东南岩溶区典型土壤的系统分类研究

为明确渝东南岩溶区典型土壤在中国土壤系统分类中的归属,以该区域石灰岩发育的典型土壤个体为研究对象,挖掘8个典型剖面,通过野外观测、分层取样与分析,依据《中国土壤系统分类检索(第三版)》进行分类检索,并与发生分类进行参比。结果表明,8个供试剖面分别被划归为3个土纲(淋溶土、雏形土和新成土)、5个亚纲、7个土类和7个亚类等系统分类高级单元;在系统分类基层单元归属上,8个剖面分别被划归为8个土族和8个土系。黄棕壤参比到简育常湿雏形土和酸性常湿雏形土,黄壤参比到简育湿润淋溶土,石灰(岩)土参比到钙质常湿(湿润)淋溶土、钙质湿润雏形土和湿润正常新成土。结合成土环境分析可知,在渝东南岩溶区海拔1 000 m的地区,海拔越高,其水分状况越好,越容易形成黏化层;若海拔大致相同,坡度是影响土壤形成黏化层的首要因素;地形和海拔也与渝东南岩溶区的土壤水分状况、雏形层的形成等密切相关,是影响渝东南土壤系统分类归属划分的重要因素。     

重庆市全新统冲积物发育土壤的系统分类研究

为明确重庆市第四系全新统(Qh)冲积物发育土壤在中国土壤系统分类中的归属,本文以该成土母质发育的土壤为研究对象,挖掘9个典型土壤剖面,通过野外观测、分层取样及理化性质分析等,依据现行中国土壤系统分类检索,对其进行分类和命名,并与发生分类进行参比。结果表明:9个供试土壤剖面分别归属于雏形土和新成土2个土纲,5个亚类,其中5个为石灰淡色潮湿雏形土,1个为铁质简育常湿雏形土,1个为斑纹简育湿润雏形土,1个为潜育潮湿冲积新成土,1个为石灰潮湿冲积新成土;隶属于发生学分类潮土土类的6个供试剖面分别归为系统分类中淡色潮湿雏形土、简育常湿雏形土和简育湿润雏形土3个土类,而隶属于发生学分类新积土土类的3个供试剖面则分别归为系统分类中淡色潮湿雏形土和潮湿冲积新成土2个土类。结合成土环境分析可知,地形、气候和母质是影响重庆市第四系全新统冲积物发育土壤系统分类的重要因素。     

宁夏山地土壤的发育规律及系统分类研究

为全面了解宁夏山地土壤的发育特性及其系统分类归属,基于宁夏土系调查项目挖掘的典型剖面,选取10个发育在宁夏贺兰山山地(剖面编号为3、11、13、14和108)和六盘山山地(剖面编号为73、82、119、120和121)的土壤作为研究对象,结合剖面形态特征和理化性质,尝试对山地土壤的发育特征和系统分类归属进行研究。结果表明:(1)发育在宁夏的10个山地土壤高级单元归属为新成土、雏形土、淋溶土和均腐土等4个土纲,正常新成土、干润雏形土、湿润雏形土、冷凉淋溶土、湿润均腐土等5个亚纲,干旱正常新成土、简育干润雏形土、暗沃干润雏形土、冷凉湿润雏形土、简育冷凉淋溶土、斑纹湿润均腐土等6个土类,石灰干旱正常新成土、普通简育干润雏形土、普通暗沃干润雏形土、暗沃冷凉湿润雏形土、普通简育冷凉淋溶土、斑纹简育湿润均腐土等6个亚类,续分为10个土族,包括粗骨砂质硅质混合型温性—石灰干旱正常新成土,粗骨砂质长石型温性—石灰干旱正常新成土,壤质长石混合型石灰性冷性—普通简育冷凉淋溶土,砂质硅质混合型非酸性冷性—斑纹简育湿润均腐土等,10个供试剖面在土族完全分异,因而续分为10个土系,包括葡萄泉系、一堆系、滚钟口系、六盘山公园系、绿塬腰系等10个土系。(2)海拔对宁夏山地土壤的发育特征有着明显影响,表现为随海拔升高:腐殖质积累过程逐渐明显、土体淋溶过程加剧、土体石灰反应逐渐减弱直至消失;土壤水分条件逐渐改善,处于高海拔位置的山地土壤土体底部有弱氧化还原反应发生,形成铁子和铁锰胶膜;土壤pH逐渐减小,土壤酸碱性发生一定的变化。(3)受成土环境和成土因素的作用,土壤发育规律在诊断特征上的反映为随海拔高度的抬升呈现一定的垂直分异规律,其中诊断表层由淡薄表层演变为暗沃表层;土壤水分状况经干旱/半干润土壤水分状况向湿润土壤水分状况演化;土壤温度状况由温性土壤温度状况变为冷性状况。     

皖南山地土壤系统分类研究

选取皖南四座山地土壤垂直带中 1 9个土壤剖面 ,研究了土壤成土环境和形成特点。根据《中国土壤系统分类 (修订方案 )》和《中国土壤系统分类———理论·方法·实践》 ,鉴定了诊断层和诊断特性 ,确定供试剖面在中国土壤系统分类中的归属。自山下到山上依次为湿润淋溶土 (伴有湿润雏形土 )———常湿淋溶土 (伴有常湿雏形土 )———正常新成土亚纲。与不同分类系统中土壤类别归属作了参比 ,同时也与福建、江西山地土壤作了比较。     

皖南紫红色砂石岩上发育土壤的系统分类研究

对皖南不同时期紫红色砂石岩上发育的8个土壤剖面,按中国土壤系统分类体系,进行鉴别、检索、分类定名。阐述发生分类紫色土的2个亚类级土壤类型在中国土壤系统分类中归为3个土纲,即均腐土、雏形土和新成土;3个亚纲,即湿润均腐土、湿润雏形土和正常新成土;4个土类和6个亚类。提出按中国土壤系统分类的紫色土分类系统;并与美国土壤系统分类、国际土壤分类参比基础进行了参比。讨论了皖南紫红色砂石岩上发育为均腐土的成土环境条件,同时对发生分类紫色土在中国土壤系统分类类别检索提出修订建议。     

云雾山自然保护区土壤发生特性与系统分类研究

对黄土丘陵区典型草原带宁夏云雾山自然保护区不同演替阶段植被下土壤的发生特性及系统分类进行了研究。结果表明:保护区内土壤保持有完整的发生层次,有明显的A层、过渡层(AB)、淀积层(B)与母质层(C);土壤颜色、结构和养分在剖面层次上明显差异;土壤有机质含量较高,最高可达到31.5g kg-1;土壤碳酸钙有明显的淋溶淀积,在剖面中下部形成淀积层;颗粒组成以0.05-0.01mm粒级的细砂粒为主,其次为<0.002mm的粘粒;土体矿质全量中,S iO2占绝对优势,A l2O3次之,化学元素的含量顺序依次为S i A l>Ca>Fe>K≈Mg>Ti>Mn。土壤发育处于物理风化为主阶段,化学风化较为微弱,矿质元素的移动不明显。供试土壤共分属2个土纲,2个亚纲,3个土类和3个亚类,其中YW-2、4属于钙积暗厚干润均腐土,YW-3、5属于普通简育干润雏形土,YW-6属于钙积暗沃干润雏形土。     

陕北地区黄绵土分类的研究

黄绵土是在黄土母质上形成的幼年土壤,没有明显的发育层次,不具有地带性土壤剖面特征,土壤性状与母质类似,剖面层次由A_p—C层或A—C层组成。根据土壤诊断层和诊断剖面特性划分为原始黄绵土和淡黄绵土两个亚类。以作物生长季节(4—9月)土壤水热状况划分温灌黄绵土、温潮黄绵土、温润黄绵土、温干黄绵土、凉润黄绵土、凉干黄绵土等土属。以表层土壤质地和有机质含量的等级差异和组合划分出28个土种。黄绵土的分布,在延安以南海拔低于1200米以下的地区,阴、阳坡土壤均属温潮黄绵土,再向北,阴坡为温润黄绵土,阳坡为温干黄绵土。海拔高度在1400米以上阴阳坡两边的土壤属凉干黄绵土,阴凉沟底地土壤属凉润黄绵土。河川地土壤通常为温灌黄绵土。     

GENESIS AND MORPHOLOGY OF SOME ALPINE PODZOL PROFILES

Some representative podzol profiles from an Alpine region are described. Their genesis is mainly a function of vegetation and drainage and is analysed by morphological, chemical, and mineralogical methods. The effect of soil management on profile development as governed by recent economic advances has been discussed. When meadows with brown soils that are preserved by careful management are abandoned, heather and bilberries start growing and podzolization processes begin. Illuviation horizons are formed that have a friable consistency when formed in these meadows, but that may be hard and brittle when developed in sandy till with only heather or bilberries. Soil physical processes lead only to a fragmentation of parent rock, whereas pronounced chemical weathering occurring in these soils—decreasing in intensity with depth—produces an active clay fraction, the composition of which is discussed. Chemical weathering was most pronounced under poor vegetation. The higher content of silt in the topsoil can be partly attributed to sedimentation of wind-blown particles. Frost action leads to sedimentation of fine soil particles on top of larger mineral fragments lying at some depth in a profile.     

Influences of alpine ecosystem responses to climatic change on soil properties on the Qinghai–Tibet Plateau, China

Alpine ecosystems are quite sensitive to global climatic changes. Drawing from two sets of remote sensing data (1986 and 2000) and field investigations, the ecological index method was used to document ecosystem changes in the Yangtze and Yellow River source regions of central Qinghai–Tibet. Although crucial to understanding alpine ecosystem responses to global climatic changes, and in assessing the potential for their rehabilitation, the impact of such changes on alpine soil characteristics, including structure, composition, water retention, as well as chemical and nutrient contents, is poorly understood. Over a 15-year period (1986–2000), climatic changes led to considerable degradation of alpine meadows and steppes. In the meadows, the surface layers of the soil became coarser, bulk density, porosity and saturated hydraulic conductivity rose, while water-holding capacity decreased. In comparison, steppe soils showed little changes in soil physical properties. Degradation of alpine ecosystems led to large losses in soil available Fe, Mn and Zn. Important losses in soil organic matter (SOM) and total nitrogen (TN) occurred in badly degraded ecosystems. Climate warming in the Qinghai–Tibet Plateau, caused by the impact of greenhouse gas, has resulted in changes of cold alpine ecosystem such as the significant alteration of the soil C and N cycles.     

Local expansion and selection of soil bacteria in a glacier forefield

In the environment of Alpine glacier forefields, bacteria represent the functional link between initial soil development and secondary colonization. An important question is whether soil bacteria are adapted to the poor nutrient availability in this environment and whether selection processes significantly limit their local expansion along the gradients of chemical and biological factors. To address these questions, we used a two‐dimensional sampling strategy at our study site, the Damma glacier forefield, Switzerland, to characterize the soil environment by selected biogeochemical parameters. Our results revealed two contrasting sites that differed in time since deglaciation (‘young’ and ‘old’ soil, ≤ 13 years and > 53 years of ice‐free conditions) and vegetation cover (threefold increase), but also showed significant differences in soil properties thought to be relevant for the successional development of glacier forefield soils, such as pH (0.5‐fold decrease), ammonium (0.5‐fold decrease) concentration, and the content of total organic carbon (10‐fold increase). Isolated strains, affiliated to the genus Pseudomonas, according to their 16S rDNA profile, were tested experimentally for local adaptation by a reciprocal transfer experiment. The bacteria from both young and old soils showed a significant interaction with their local environment; the direction of the interaction, however, did not follow the expected pattern of local adaptation. The significant genoype‐with‐environment interaction indicates a limited local expansion of soil bacteria in the Damma glacier forefield over the range of only 110 m. The lack of local adaptation could be explained by environmental constraints such as exclusion of competition, different migration behaviour of bacteria from young and old soil, or the ability of early colonizing bacteria to survive under the glacier ice.     

新疆博格达山北坡土壤形成特征及其垂直分布

博格达山北坡土壤形成过程主要有腐殖质化过程、粘化过程、钙他过程、残余盐化-碱化过程、高山融冻过程.土壤风化程度低,粘土矿物以伊利石为主,粘粒SiO₂/R₂O₃为2.84-3.54,各土类差别不大,R₂O₃,沿剖面无明显移动.本区山体高大,土壤垂直分布完整,在天山北坡有代表性,并具温带荒漠土壤的垂直分布特点.土壤垂直分布东、西差异明显,西部完整,东部无荒漠土壤和高山草甸土.     

Wind tunnel test and Cs tracing study on wind erosion of several soils in Tibet

The soils of alpine meadows and alpine grassland steppes, aeolian soils, coarse-grained soils, and farm soils cultivated from alpine grasslands in Tibet are typical soils that are suffering from different degrees of soil erosion by wind. Based on field investigations, wind tunnel experiments, and a ¹³⁷Cs trace study, this work tested the erodibility of these soils by wind, simulated the protective functions of natural vegetation and the accelerative effects of damage by livestock, woodcutting, and cultivation on erosion, and estimated erosion rates from 1963 to 2001. The results indicated that alpine meadows have the strongest resistance to wind erosion, and that undamaged alpine meadow soils generally sustain only weak or no wind erosion. Alpine grassland steppes with good vegetation cover and little damage by humans exhibit good resistance to wind erosion and suffered from only slight erosion. However, soil erodibility increased remarkably in response to serious disturbance by livestock and woodcutting; wind erosion reached 33.03 t ha⁻¹ year⁻¹. The erodibility of semi-stabilized aeolian soil and mobile aeolian soil was highest, at 52.17 and 56.4 t ha⁻¹ year⁻¹, respectively. The mean erosion rates of coarse-grained soil with various levels of vegetation coverage and of farm soil were intermediate, at 45.85 and 51.33 t ha⁻¹ year⁻¹, respectively. Restricting livestock, woodcutting, and excessive grassland cultivation are the keys to controlling wind erosion in Tibet. In agricultural regions, taking protective cultivation and management to enhance surface roughness is a useful way to control wind erosion.     

ALPINE SOILS OF NORTH-EAST SCOTLAND

Many features of the alpine soils of NE. Scotland are related to altitude. The deep contemporary humose A horizon has formed in Post-Boreal to recent times. Its formation was preceded by a phase of profile development characterized by very scanty A horizon development. This phase was interrupted by a stage of frost disturbance, probably equated with the Highland Re-advance. The earliest part of the pedogenetic cycle is represented only by cryogenic redistribution of the fine fraction, within the parent material column, which occurred between 12,000 and 28,000 B.P.     

红黄壤的石灰位

Aslyng^[2]和Schofield^[5]提出了“石灰位”的概念.石灰位的数学表示式为pH-0.5pCa,它是土壤中石灰[Ca(OH)₂]的数量的一个函数.以后,一些学者研究了石灰位的影响因素.     

黄土区土壤微量元素含量分布与微肥效应

黄土区土壤微量元素含量分布受母质、地形、水热条件、土壤类型等成土过程与成土条件的深刻影响,呈现出一定的规律性。与全国土壤平均含量比较,本区土壤锌、锰较低,钼很低,硼接近,铜略高。土壤有效态锌、硼、钼、锰属低水平,存在着大面积缺乏锌、硼、钼的土壤,近一半土壤面积缺锰。近年来,锌、硼、锰肥已在生产中大面积应用,获得了显著的经济效益。     

山地森林土壤枯枝落叶层结构和功能的研究

本试验设置在卧龙自然保护区1200-4300m海拔高度不同生物气候带的森林类型下.五处试验林地是:1.常绿阔叶林下的山地黄壤;2.次生落叶阔叶林下的山地棕壤;3.针阔混交林下的山地暗棕壤;4.暗针叶林下的山地棕色暗针叶林土;5.高山草甸植被下的高山草甸土.通过1981-1984年进行定位观测和试验研究,其结果阐明了该林区森林枯枝落叶层的构型、贮量及其化学、物理性质和灰分元素组成等;并探讨了森林枯枝落叶层在森林土壤生态系统中对水源涵养、养分供应、促进生物活动强度和土壤发育等方面的功能.