Pedodiversity: a controversial concept

1 Conceptual introductionSpatial soil variation is a fundamental notion of pedology, formally expressed in the hierarchical system of soil taxonomy and soil associations[1,2]. Since the 1990s, a Spanish research team led by Ibá?ez has been presenting a possible approach to systematically analyze taxonomic diversity of pedosphere by methods employed in ecological studies, drawing a parallel with the concept of biodiversity in ecology. According to Ibá?ez et al., it would be quite reasonable …     

海南岛不同地形上土壤性质的多样性分析

多样性指数长时间以来在生态学领域被用于分析不同生态体的发生规律,本研究将类似手段用于某些土壤性质 (土壤发生层次、土层厚度和土壤容重) 多样性的分析中,讨论基于海南岛土壤－地形体数字化数据库 (SOTER),通过对不同地形上土壤发生层次、土层厚度和土壤容重等某些土壤性质类别SOTER单元的丰富度指数 (S)、多样性指数 (Shannon指数H') 和均匀度指数 (Pielou E) 的计算,类别多度分布模型的应用,并在地理信息系统环境中实现了海南岛不同地形上某些土壤性质多样性分析的数字化表达。     

城市化对南京地区土壤多样性影响的灰色关联分析

随着城市化的发展,越来越多的土壤资源被侵占。本文借助RS和GIS技术,根据1984年、1995年、2003年3期TM遥感影像 (30m×30m),采用多时相连续对比法对南京地区近20年来城镇扩张情况进行了分析;结合南京地区土壤图,利用生态学领域中的多样性测度方法计算了城市化背景下南京地区的土壤多样性指数 (HP)、土壤均匀度指数 (Jsw) 和土壤丰富度指数 (R₂),进而在镇级尺度上对1984~2003年南京地区土壤多样性时空变化特点进行了研究;利用灰色系统理论中的灰色关联分析方法,对南京地区各级行政区划单位的扩张对土壤多样性的影响进行了初步探讨。分析结果表明,各级行政区划中村庄的扩张对土壤多样性指数的影响最广,约占研究区总面积的60%;镇、县和市的扩张对土壤多样性的影响逐渐减少,各占研究区总面积的26%、7%和7%。     

A pedodiversity pattern: taxonomically established soil orders in China

1GeneralsituationofstudyChina is one of the oldest civilized countries in the world. Human activities and the practice of agriculture date back nearly 10 thousands years when people began gaining an understanding and knowledge about soils. Records of these activities can be found in ancient or current Chinese references (Gong etal., 1999), and in non-Chinese literatures like those in English and Russian (Thorp, 1936; Kovda, 1960; Needham, 1986; Li and Cao, 1990; Gong etal., 2003). Soil cl…     

Soils of Namaqualand: Compensations for aridity

The soil mantle in Namaqualand is immature in terms of weathering. Despite or even because of this, the diversity and spatial variability of soil physical and chemical properties is exceptionally high and could be fundamental in governing biodiversity and ecosystem function. In arid landscapes, the way the soil sheds, admits, stores, diverts and transmits water is crucially important. Namaqualand's soils possess special features, which modify water infiltration, hydraulic conductivity and subsurface storage and provision of water to plants. These include pedodermal crusts; a natural mulch of surface gravel or desert pavement; water-repellent soils with fingered infiltration of rain water; textural discontinuities at depth; subsurface horizons cemented with silica, calcite, fibrous clays or gypsum; soluble salts that affect plant water uptake osmotically; clay minerals having exceptional water-absorbing capacity and that are unique to arid environments; and a mechanism, in deeper sandy soils, for thermally induced upward transport of water vapour—a kind of nocturnal distillation—that seems to lessen the need for plants to root deeply.Superimposed on this already impressive pedodiversity are the almost ubiquitous heuweltjies—broad, low mounds which add further complexity to fluxes of water, salts, energy and nutrients in the landscape.     

中国中、东部典型样区不同发展水平下土壤与土地利用多样性的对比分析(英文)

Two typical provincial capitals (Nanjing and Zhengzhou) and two counties (Rugao and Yuanyang) in east (Jiangsu Province) and central (Henan Province) China were chosen respectively as the developed and less developed comparative cases for pedodiversity and land use diversity correlative analysis by borrowing the recently better developed pedodiversity methodology. Land use classification was worked out using remote sensing images in three different periods (1986-1988, 2000-2001 and 2004-2006) for these studied case areas before the calculation of the constituent diversity index and spatial distribution diversity index modified after Shannon entropy in 2 km×2 km grid scale of the soil and land use pattern were conducted and then a connection index was proposed to evaluate the relationship between soil and land use diversity. Results show that during the years from 1986 to 2006, the composition and spatial distribution of regional land use pattern had changed greatly. The agricultural land area of all the studied case areas decreased obviously in which Nanjing has the highest decrement of 895.98 km 2 mainly into urban use while the other land use type area changes show the same trend. The connection index of four typical soil family types and typical urban land use types, i.e., urban construction land, transportation land and industrial and mining area all increased in this period. In the studied case areas, there is the highest soil constituent diversity in Zhengzhou at 0.779 while the simplest soil constituent diversity in Rugao at 0.582. Meanwhile we have higher land use diversity in the more urbanized Jiangsu Province than Henan Province, Nanjing is ranking the first that has been getting higher and higher in the three periods at 0.366 in 1986-1988, 0.483 in 2000-2001 and 0.545 in 2004-2006. Finally, the connection index figures to evaluate the relationship between soil and land use diversity of the studied areas were compared to show the similar phenomenon that this figure grows fastest in Nanjing followed by Zhengzhou and other places.     

SOIL PROCESSES AND DEVELOPMENT RATES IN THE QUARTERMAIN MOUNTAINS, UPPER TAYLOR GLACIER REGION, ANTARCTICA

Soil‐forming processes and soil development rates are compared and contrasted on glacial deposits in two adjacent and coeval valleys of the Quartermain Mountains, which are important because they display Miocene glacial Stratigraphy and some of the oldest landforms in the McMurdo Dry Valleys. More than 100 soil profiles were examined on seven drift sheets ranging from 115 000 to greater than 11.3 million years in age in Beacon Valley and Arena Valley. Although the two valleys contain drifts of similar age, they differ markedly in ice content of the substrate. Whereas Arena Valley generally has ‘dry‐frozen’ permafrost in the upper 1 m and minimal patterned ground, Beacon Valley contains massive ice buried by glacial drift and ice cored rock glaciers and has ice‐cemented perma‐frost in the upper 1 m and considerable associated patterned ground. Arena Valley soils have twice the rate of profile salt accumulation than Beacon Valley soils, because of lower available soil water and minimal cryoturbation. The following soil properties increase with age in both valleys: weathering stage, morphogenetic salt stage, thickness of the salt pan, the quantity of profile salts, electrical conductivity of the horizon of maximum salt enrichment, and depth of staining. Whereas soils less than 200 000 years and older soils derived from sandstone‐rich ground moraine are Typic Anhyorthels and Anhyturbels, soils of early Quaternary and older age, particularly on dolerite‐rich drifts, are Petronitric Anhyorthels. Arena Valley has the highest pedodiversity recorded in the McMurdo Dry Valleys. The soils of the Quartermain Mountains are the only soils in the McMurdo Dry Valleys known to contain abundant nitrates.     

FDR在高寒草地土壤水分测量中的标定及其应用

FDR(Frequency Domain Reflectometry)———频域反射仪是一种用于测量土壤水分的仪器,这是一种利用电磁脉冲方法,根据电磁波在介质中传播速度来测试介质的介电常数从而测定土壤水分的仪器。通过介绍FDR系统在高山草甸土上的校正结果,研究表明,野外校正比较符合实际情况,可以作为青藏高原地区高山草甸土进行FDR校正的参考。由于具有快速、准确等优点,能自动、连续地监测土壤含水量,FDR是一种值得推广的土壤水分测定仪器。     

~(137)Cs示踪法土壤侵蚀量估算的本底值问题

137Cs示踪法因能快速、相对简便地估算土壤侵蚀量而在土壤侵蚀定量研究中得到广泛应用。本底值获取是137Cs示踪法的关键和基础。在具有空间异质性多因素综合作用下,本底值呈现高度的空间异质性。针对本底值空间变异性,从气候气象要素、地形、土壤属性、土地利用/覆被四个方面阐明各因素与本底值空间变异的作用机理。分析了当前137Cs示踪法应用中在本底值获取时参考点存在性及选点的准确性、单个或几个本底值对研究区本底值的代表性和参考点采样设计。提出划分侵蚀测定单元、建立多本底值体系和进行地形校正解决当前137Cs示踪法中本底值存在问题的对策。侵蚀测定计算单元的划分原则和方法、根据已有参考点的137Cs本底值推算各单元137Cs本底值的技术方法、定量化研究各因素对137Cs的作用是今后需要深入的工作。     

土壤风蚀野外测量技术研究进展

野外测量是使用最早、应用最广的土壤风蚀研究方法。经过几十年的努力,国内外学者已开发出一系列土壤风蚀野外测量仪器与技术。由于没有制定统一的标准,目前世界各国使用的野外测量仪器和技术并不相同,这给研究结果的比较与集成造成一定困难,不利于交流与合作。基于此,本文对国内外土壤风蚀野外测量技术进行了全面梳理,归纳了土壤风蚀野外测量技术的发展历史,并从风蚀影响因子测量、风蚀物收集和风蚀量确定3方面详细介绍了土壤风蚀野外测量技术的研究进展,比较了不同类型仪器与方法的优缺点,指出目前一些被广泛采用的技术手段,并对今后土壤风蚀野外测量技术的发展趋势进行了展望,以期为中国土壤风蚀野外测量技术的发展提供参考。     

西天目山南坡垂直自然带分异规律

西天目山为国家自然保护区,生物物种丰富,其南坡垂直自然带谱明显,本文论述西天目山南坡垂直自然带分异规律。     

科尔沁沙质草地不同恢复年限草本层群落结构及其与土壤理化性质的关系

草本植物在沙地植被恢复过程中具有重要作用,研究自然恢复沙质草地草本层植物群落组成变化规律及其与土壤因子之间的关系,对植被与土壤恢复具有重要的意义.本研究对科尔沁严重退化沙地封育12、17年和20年的自然恢复沙质草地植物组成和土壤理化性质进行研究,同时分析了植物组成与土壤因子的相关关系.结果表明:随着恢复年限的增加,土壤...     

一二年生植物在坝上沙质退耕地上的引种筛选

一二年生植物引种成功的种源区域范围及科属范围都较多年生植物广，而对土壤基质、水分、人为活动等具体生境差异反应明显。最佳的引种植物有临夏燕麦、丹麦４４４燕麦、黑圆箭舌豌豆、３３３Ａ箭舌豌豆及Ｐｈａｌａｒｉｓ属的几个种等。     

影响草地土壤呼吸的主要自然因子研究现状

草地生态系统作为陆地生态系统的主体生态类型之一,脆弱的生态环境与频繁的人类活动使之较其他生态系统对全球气候与环境变化的响应更为迅速。草地土壤通过土壤呼吸作用向大气释放CO2是草地生态系统碳循环中最主要的一个环节,土壤呼吸量直接决定了土壤中碳素周转的速度。综合介绍了国内外草地土壤呼吸的研究现状,特别分析了一些自然因素对草地土壤呼吸的影响,对未来测定土壤呼吸的方法提出建议。     

土壤水研究的进程和展望

本文评述了近年来土壤水的理论研究及共方法、应用性研究的进展情况。     

不同地质背景下发育的土壤及其对物种多样性的影响

以重庆金佛山地区为例,分析土壤基本理化性质与成土母质和植被的关系,并对石灰岩和砂页岩地区的生物多样性及其与土壤基本理化性质的关系进行了探讨。结果表明,成土母质对土壤基本理化性质的影响主要体现在钙镁总量上,但这种影响随着土壤发育的成熟和植被正向演替的进展逐渐减弱;不同母质地区的物种多样性指数均与土壤钙镁含量呈明显的负相关,在土壤发育和生态恢复初期,土壤中较高的钙镁含量对物种多样性有一定的限制作用;石灰岩地区的物种多样性与土壤因子的关系更为复杂,导致群落的不稳定性增强。