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紫色土系统分类发展认识及其与土壤普查分类的对比 总被引:1,自引:0,他引:1
本文在回顾紫色土分类进展的基础上,围绕《中国土壤系统分类(修订方案)》,讨论一些长期困以土分类的问题,并根据“修订方案”,逐一检索和对照四川省第二次土壤普查分类所设土种,以期“修订方案”在土壤研究和生产初中中得到更加广泛的应用。 相似文献
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广东土壤及其农业利用改良区域 总被引:5,自引:0,他引:5
陆发熹 《热带亚热带土壤科学》1998,7(4):299-308
综合论述广东土壤的形成,分类和利用改良分区,阐述了黄壤、红壤、赤红壤、砖红壤和水稻土等主要土类的性质及利用现状,分析了各个地带、各个地区的自然条件、土壤组合以及土壤利用改良的特点。针对这些特点,提出了广东今后土壤资源利用的具体措施。 相似文献
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世界土壤资源参比基础(WRB)的创立及其土壤分类 总被引:2,自引:0,他引:2
在简述了由IRB到WRB的发展过程和WRB的特点以后,重点叙述了WRB向在墨西哥召开的15届国际土壤学大会提交的土壤分类方案中的诊断层,诊断特性和诊断物质,最后全面介绍了这一方案的一,二级分类单元。 相似文献
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Abstract. This paper describes a soil classification system developed for agronomists in Cambodia that has proved useful in improving soil fertility management. The classification system relies on soil characteristics that are easily identifiable in the field and have agronomic relevance. The system was used in the on-farm trial programme of the Cambodia-IRRI-Australia Project (CIAP) in 1996 and 1997 to determine whether it could adequately discriminate between soil types and improve fertility management. Using diagnostic criteria that could be identified in the field, 11 soil groups were defined and subdivided into a further 20 phases. Soil groups were defined as units of morphologically similar soils, which occurred at the same position in the landscape. Classification of soil phases within a soil group was primarily based on soil properties that had significance for crop production, this included information gained from local experience and expertise. A modified version of the Fertility Capability Classification (Sanchez et al., 1982) was added as a third level to allow a more quantitative classification in cases where soil analytical data was available, and to facilitate the transfer of agronomically important soil information from outside Cambodia. The soil groups adequately predicted differences in grain yields of rice grown on the different soils in on-farm trials and provided the basis for soil-specific management recommendations. Local agronomists have welcomed the system and have incorporated it into their research and extension operations. 相似文献
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土壤质地分类及其在我国应用探讨 总被引:35,自引:1,他引:35
土壤质地是土壤重要的物理特性之一,严重影响土壤的持水、通气等特性,研究统一土壤质地分类制意义重大。针对我国土壤质地分类制混用的现象,文章在介绍国内外主要的土粒分级标准,比较四种土壤质地分类制的特点,回顾第二次土壤普查初期采用前苏联的卡庆斯基制,后期采用国际制的基础上,重点对比了我国的国标、各部门行标或规范等所运用的土壤质地分类标准。研究发现我国目前还没有普遍采用统一的土壤质地分类系统。土壤质地分类推荐采用美国制。 相似文献
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Classification of Urban and Industrial Soils in the World Reference Base for Soil Resources (5 pp) 总被引:1,自引:0,他引:1
David G. Rossiter 《Journal of Soils and Sediments》2007,7(2):96-100
Background, Aim and Scope
Historically, built areas were ignored in soil mapping and in studies of soil formation and behaviour. It is now recognized
that these areas, and therefore their soils, are of prime importance to human populations. Another trend is the large increase
in reclaimed lands and new uses for old industrial areas. In several countries there are active projects to map such areas,
either with locally-developed classification systems or ad-hoc names. Soil classification gives unique and reproducible names
to soil individuals, thereby facilitating correlation of soil studies; this should be possible also for urban soils. The World
Reference Base for Soil Resources (WRB) is the soil classification system endorsed by the International Union of Soil Science
(IUSS). The 2006 edition has important enhancements which allow urban and industrial soils to be described and mapped, most
notably a new reference group, the Technosols.
Main Features
Urban soils are first defined, followed by the philosophical basis of soil classification in general and the WRB in particular.
WRB 2006 added a new Technosols reference soil group for soils whose properties and function are dominated by technical human
activity as evidenced by either a substantial presence of artefacts, or a impermeable constructed geomembrane, or technic
hard rock. Technosols are one of Ekranic, Linic, Urbic, Spolic or Garbic; further qualifiers are added to show intergrades
to other groups as well as specific soil properties. Soils from fill are recognized as Transportic Regosols or Arenosols.
Toxic soils are specifically recognized by a qualifier.
Results
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Discussion
The limit between Technosols and other groups may be difficult to determine, because of the requirement that the technic nature
dominate any subsequent pedogenesis.
Conclusions
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Perspectives
The WRB should certainly be used in all urban soil studies to facilitate communication and correlation of results. In the
period leading up to the next revision in 2010, the quantitative results from urban soil studies should be used to refine
class definitions. 相似文献
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慈溪市土壤系统分类研究 总被引:6,自引:0,他引:6
本文对浙江省慈溪市第二次土壤普查土壤分类系统进行了修订,并建立了慈溪市土壤系统分类,依据浙江省土系建立的原则和要求,初步建立了慈溪市土壤的土族和土系。 相似文献
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The rice soils of Cambodia. II. Statistical discrimination of soil properties by the Cambodian Agronomic Soil Classification system (CASC) 总被引:1,自引:0,他引:1
Abstract. A novel agronomic system of soil classification for managing rice soils in Cambodia (CASC) was developed recently. It integrates local knowledge about the soil with its conceptual and taxonomic understanding by soil scientists. Using quantitative soil survey data we evaluated the agronomic efficacy of the classification system. Although the CASC is based on simple field criteria it explained 25 to 44% of the variation in soil prop-erties relevant for agronomic decision making. It failed, however, to differentiate soil types based on pH (6% of variances explained). Despite its simplicity it performed as well or better than the most widely used soil map in Cambodia (Crocker, 1962), and unlike this small-scale soil map it allows classification on a field-specific basis. The average values of soil properties were often significantly different between groups. Organic carbon, clay content and plant available magnesium and calcium contributed most to the discrimination of CASC soil groups. The predictive accuracy when allocating new samples on the basis of quantitative survey data to soil groups of the CASC was 50% to 100%, except for soil groups Kein Svay (0%) and Kampong Siem (20%). The CASC is valuable for managing Cambodian rice soils and may also be used for up-scaling and mapping of soil information. 相似文献
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不同土壤水分与温度条件下土根系统中水分传导的变化及其相对重要性 总被引:7,自引:2,他引:7
依据试验资料,分析了土壤水势和温度对根系收缩程度、土根间隙水分传导和土根系统中各部分水分传导相对重要性的影响。结果表明:植物根系收缩程度银合欢<台湾相思<向日葵<玉米,植物在水分胁迫下的根系收缩能反映植物的抗旱性;在相同土水势条件下,土根间隙水分传导表现出银合欢>台湾相思>向日葵>玉米;在土根间隙传导(Lg)、根系传导(Lr)与土壤有效传导(Ls)三者之间,Ls的变幅最大,Lr的变幅最小,对于不同植物种类Lr、Lg与Ls成为系统中的水分传输限制因子所对应的土水势范围不同;当土水势(ψ)高于-1.0MPa时,温度升降对玉米与向日葵的根系收缩无显著影响,当ψ<-1.0MPa时,高温环境中的根系收缩加剧,当ψ>-1.10MPa时,玉米、向日葵的Lg随温度增加而略有增加,而当ψ<-1.10MPa时,其Lg则随温度增高而下降。 相似文献
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Soil properties and soil water conditions were assessed for different land use (forest, arable land, grassland) on a silty Calcaric Regosol in the Yangjuangou Catchment of the Chinese Loess Plateau. The loess here is unimodal, poorly sorted with abundant coarse silt, has very low dry bulk density (1.11?–?1.38?g cm???3) and little organic carbon content (1.6?–?3.7?g kg???1). The soils are hydrophilic, have high porosity (0.5?–?0.55 cm3?cm???3), unsaturated hydraulic conductivity, and plant available water content (0.34?–?0.4 cm3?cm???3). Soil properties are quite uniform in space. Land use had no significant effects on soil properties and soil water conditions. 相似文献
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长期施肥对黑土和暗棕壤土壤酶活性及土壤养分的影响 总被引:7,自引:2,他引:7
为阐明长期施肥对黑土和暗棕壤土壤酶活性的影响、土壤酶活性与土壤养分的关系,探讨土壤持续利用的培肥模式,采集了施用不同肥料28年后的黑土和暗棕壤,对黑土和暗棕壤土壤酶活性以及土壤养分因子进行了测定和分析。结果表明,与不施肥对照相比,各施肥处理均可显著增加黑土和暗棕壤有机质和氮磷钾养分含量,提高土壤脲酶、磷酸酶、转化酶、过氧化氢酶活性,其中以化肥配施有机肥效果最为明显。土壤酶活性与土壤养分之间有很好的相关性,土壤脲酶、磷酸酶、转化酶、过氧化氢酶活性与土壤有机质、全氮、全磷、碱解氮、速效磷含量呈显著相关,黑土对施肥比暗棕壤对施肥更敏感。对不同土壤长期化肥配施有机肥均可为作物生长创造良好的土壤环境。 相似文献
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石灰岩区土壤分形特征及其与土壤性质的关系 总被引:4,自引:0,他引:4
研究了岩溶坡地不同生态系统土壤颗粒组成和团粒结构的分形特征.结果表明,土壤颗粒组成分形维数与黏粒及物理性黏粒含量显著正相关,与砂砾含量显著负相关.团粒结构分形维数与水稳性团聚体含量显著负相关,与团聚体湿筛后的破坏率显著正相关,即分形维数愈高,>0.25 mm水稳性团聚体和水稳性大团聚体含量愈低;团粒结构的分形维数与土壤有机质有负相关趋势,与土壤阳离子交换量显著负相关,与土壤体积质量(容重)呈正相关趋势.次生灌丛岩溶生态系统退化后,土壤黏粒减少,体积质量上升,土壤水稳性团聚体含量及其稳定性下降,土壤颗粒组成分形维数降低,土壤团粒结构分形维数则呈上升趋势.颗粒组成分形维数与团粒结构分形维数对土壤质量和岩溶生态环境状况的反映是一致的. 相似文献