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选取河南省10个典型含有人工制品的土壤剖面和3个自然土壤剖面作为研究对象,基于剖面形态和理化性质的分析,根据世界土壤资源参比基础(WRB)、美国土壤系统分类(ST)、中国土壤系统分类(CST),对供试土壤进行分类研究。结果表明,WRB中关于人工扰动的前缀修饰词或后缀修饰词不能完全适宜于中国地区的含有人工制品的土壤,而在ST中,含有人工制品的土壤类型出现在各个土纲及其包含的亚类单元,CST中缺乏明确的诊断依据来描述、解释含有人工制品的土壤特征。参照WRB和ST中关于人工制品类别相关标准,提出CST中含有人工制品的土壤定义,新增"技术扰动层"诊断特性,制定CST人工制品类别标准,并将这一标准体现在CST土族命名中,该分类方案能有效体现不同人为活动对土壤的影响结果,一定程度上填补我国对这类土壤分类研究的空白。 相似文献
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土壤环境变化对土壤动物群落影响的研究 总被引：48，自引：6，他引：48
土壤是环境系统中物质与能量交换的枢纽 ,土壤动物在土壤物质能量迁移转化过程中具有特殊的功能和作用。然而 ,随着人类活动对环境影响的加剧 ,原生植被受到破坏 ,各种污染物质不断在土壤中富集 ,对土壤动物的生存繁衍带来严重威胁 ,目前土壤动物学者的研究 ,主要集中在土壤动物在成长过程中的作用 ,理化性质的改良 ,土壤养分循环以及区系分类等 ,很少涉及土壤动物与环境特别是污染环境关系的研究。农药是目前主要的化学性环境污染物 ,农药污染对自然和农田生态系统的结构和功能都有影响[1] ,有实验表明 ,农药污染对土壤动物新陈代谢及卵的… 相似文献
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扰动地表及不同坡位土壤养分特征分析 总被引：1，自引：0，他引：1
通过径流小区试验,研究了20m坡长条件下人为扰动地表后不同坡位的土壤养分含量特征。研究结果表明,上坡和下坡扰动地表小区土壤养分含量均低于同一坡位自然坡面小区。其中,上坡7个养分指标含量差异均达极显著水平;下坡除土壤有机质含量差异不显著外,其他养分指标含量差异也达极显著水平。中坡,除土壤全氮、有机质及全磷含量是扰动地表小区极显著高于自然坡面小区外,其他土壤养分指标含量也是扰动地表小区极显著低于自然坡面小区。但是从整个径流小区坡面看,自然坡面小区土壤养分含量明显高于扰动地表小区。不同坡位,对于扰动地表小区,土壤氮素、钾素及有机质含量高低依次为下坡中坡上坡;土壤磷素含量高低依次为中坡下坡上坡。对于自然坡面小区,土壤氮素、钾素及有机质含量是下坡上坡中坡;土壤磷素含量是下坡中坡上坡。 相似文献
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河南仰韶村文化遗址的土壤指示特征研究 总被引：3，自引：0，他引：3
人类作为生物因素的重要组成部分,其对土壤的影响越来越受到关注。在古人类遗址土壤研究中,通过分析土壤理化性质以及包含物特征,可还原古人类活动类型以及强度。在河南仰韶村文化遗址内,分别选取一个受到古人类活动干扰的土壤剖面(简称文化剖面)和没有受到古人类活动干扰的土壤剖面(简称自然剖面),通过观察和分析,比较两个剖面在遗物遗迹、土壤理化性质以及植物遗存方面的差别,从而获取该遗址的土壤指示特征。研究结果显示文化剖面中出现陶片、石器、灰坑、灰烬层和文化层;通体粒度组成偏砂,在灰烬层砂粒含量达到最大;低频磁化率(χlf)高于自然剖面,且出现异常高值,频率磁化率(χfd)略低于自然剖面;色度参数红度(a*)、黄度(b*)、亮度(L*)值低于自然剖面,均在灰烬层出现最小值;容重小于自然剖面,在文化层出现最小值;全磷含量高于自然剖面,在灰烬层和文化层出现极大值和最大值;禾本科(Gramineae)和藜科(Artemisia)含量高于自然剖面,存在驯化的粟、黍、水稻植硅体;有机碳同位素(δ13C)值较自然剖面偏正,指示剖面植物类型以C4为主;炭屑含量大约为自然剖面的4倍。土壤在古人类活动影响下,宏观上,土体中的侵入体和剖面形态特征与自然剖面具有明显的差别;微观上,粒度组成、磁化率、色度、全磷、容重、孢粉、植硅体、炭屑和有机碳同位素也与自然剖面有明显的差别。 相似文献
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通过伽马灭菌的方式,将两种不同性质的土壤(自然土和农田土)进行灭菌,再互相接种未灭菌土壤,研究了改变土壤性质对真菌温度敏感性的影响。结果表明,改变土壤性质虽显著影响真菌总丰度,但对真菌总丰度的温度敏感性无显著性影响。然而,部分土壤真菌个体(分类操作单元OTU)对温度具有敏感性,改变土壤性质会对温度敏感真菌个体产生影响。首先,改变土壤性质使自然土壤真菌中的热响应真菌目的个数由2减少为1,使农田土壤真菌中的冷响应真菌目的个数由5增加到9;其次,升温使自然土壤的真菌在自然土壤中冷响应和热响应真菌累积相对丰度之和从2.22%减少为1.35%,在农田土壤中从1.25%减少为0.56%;升温使农田土壤的真菌在农田土壤中冷响应和热响应真菌累积相对丰度之和从13.66%增加到19.03%,在自然土壤中从6.01%减少为2.51%;再次,改变土壤性质使自然土壤的热响应真菌由Capnodiales、Chaetothyriales变为Eurotiales,农田土壤的热响应真菌由Capnodiales、Sordariales变为Chaetothyriales、Hypocreales;自然土壤的冷响应真菌由Chaetosphaeriales、Sordariales等变为Capnodiales、Hypocreales等,农田土壤的冷响应真菌由Chaetothyriales、Eurotiales等变为Capnodiales、Sordariales等;最后,各真菌在目水平上的相对丰度变化率也各不相同。本研究表明,改变土壤性质可显著影响真菌群落结构的温度敏感性,进而可能改变真菌功能的温度敏感性。 相似文献
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高速公路路域土壤特性分析及其质量评价 总被引：1，自引：0，他引：1
为深入研究不同扰动方式对路域土壤理化特性的影响,及路域不同部位土壤的特性,以高速公路路基、路堑、弃渣场、路肩、取土场5个部位的土壤为研究对象,对采集土壤样品的理化指标进行测定和分析。结果表明:挖和填两种扰动方式对土壤质地影响不显著,含水量及容重表现为:挖方>填方>自然;路域不同部位土壤含水量、容重呈现出取土场>路堑>路基>路肩>弃渣场>自然,土壤有机质和全氮的含量呈现为:自然>路肩>路基>路堑>弃渣场>取土场;扰动土壤的有机质、全氮和速效钾含量低于自然土壤,速效磷和全磷含量高于自然土壤;扰动土壤的机质和全氮极显著相关,全氮与无机氮显著相关,与速效钾极显著相关、与速效磷负相关、容重和无机氮负相关;路域土壤有机质、全氮、全磷缺乏,土壤肥力低。 相似文献
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古人类活动对土壤发育的影响——以河南仰韶村文化遗址为例 总被引：2，自引：0，他引：2
选择在河南仰韶村文化遗址内,分别选取一个受到古人类活动干扰的土壤剖面(简称文化剖面)和没有受到古人类活动干扰的土壤剖面(简称自然剖面),通过分析和比较两个剖面中炭屑、各种氧化物含量和土壤发育指标数值,研究古人类活动对土壤发育的影响。研究结果显示,在古人类用火形成的灰烬层中,炭屑含量达到最大值2.38×105粒g-1,约为自然剖面最高值的12.35倍,这使得Si O2、Al2O3、Fe2O3、K2O、Mg O和Na2O含量相对减少,均达到最小值,而Ca O、Mn O含量达到最大值,表明古人类用火产生大量含Ca和Mn物质;而在古人类居住形成的文化层中,除Si O2几乎无变化外,其余物质均出现最大值或达到波峰,表明古人类居住活动有利于各种氧化物的富集。文化剖面发育指标数值总体高于自然剖面,在文化剖面内,文化层和灰烬层的上覆和下伏自然土层中各种元素物质含量基本相同,表明古人类活动阻碍了各种元素物质向下迁移和聚集,使下伏自然土层保持在一个相对封闭的环境中,由此推测古人类活动基本阻碍了土壤发育进程。 相似文献
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秦岭火地塘林区主要树种根际微生态系统土壤性状研究 总被引：22，自引：0，他引：22
研究了秦岭火地塘林区油松,华山松,锐齿栎和华北落叶松４个树种根际微区土壤特性,结果表明,４个树种根际土壤的pH值均低于非极际土壤,其中华北落叶松影响最明显,pH值相差达１个单位,锐齿栎影响最小,有机质含量４个树种则均是根际土壤大于非根际土壤,锐齿栎根际土壤的有机质含量最高,全Ｎ,水解N必 Ｋ含量,在根际出现一定程度的富积,速效Ｐ则在根际土壤明显产生亏缺,全Ｐ在根际土壤和非极际土壤之间的差异不明显,土壤微生物总量和３种土壤酶活性均有根际土壤高于非根际土壤,说明极系的生理代谢活动能明显增根际土壤生物活性和物质转化速率。 相似文献
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Soils with intricate patterns of their humus profiles developing in the neutral-calcium landscapes of the southern taiga of
Western Siberia under highly dynamic paleogeographic, climatic, and weather conditions are characterized. The specific features
of these soils comprise the diverse modern humus horizons along with the relic ones of different preservation rates, shallow
leaching of carbonates, and a weak development of the middle-profile soil horizons. Specifying these organo-accumulative soils is substantiated by their high humus content against the geochemical
background of the clayey calcareous parent rocks. The conjugated series of soils reflect different stages of the soil evolution
(the humus profile degradation, the development of eluvial process, and the increase of contrasts in the acid-base conditions)
and the hydromorphic transformation accompanied by the formation of organic horizons making the humus profile more complicated.
In accordance with the diagnostic horizons, the position of the soils studied was determined in the Classification and Diagnostics of Soils of Russia. The relic enrichment of the humus horizon is proposed to be used as a specific feature of these soils. 相似文献
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Pedogenetic soil horizons are one of the fundamental building blocks of modern soil classification; however, in soils of urban areas which are often strongly disturbed by human activities, horizons are difficult to distinguish but substitutive morphological layers may be identified. To identify the characteristic soil layers in an urban environment, 224 soil layers of 36 in-situ pedons were examined and described in urban and suburban Nanjing, and 27 variables were extracted for multivariate analysis. Three groups and six subdivisions were identified by TwoStep cluster analysis combined with hierarchical cluster analysis based on factor scores. Soil forming factors and soil forming processes could be interpreted from the principal component analysis （PCA） of variables, cluster analysis of soil layers, and discriminant analysis of soil layer groups and their subdivisions. Parent materials, moisture regimes, organic matter accumulation, and especially nutrient accumulation were the main causes of characteristic soil layer formations. The numerical approaches used in this study were useful tools for characteristic soil layer identification of urban soils. 相似文献
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定边县板凳滩移民区土壤发生特性与系统分类研究 总被引：1，自引：0，他引：1
通过对陕西省定边县板凳滩移民区2 500hm2未利用地的调查及不同深度剖面土样的分析,研究了不同地形和不同植被下土壤的发生特性及系统分类。项目区内土壤没有完整的发生层次;土壤颜色、结构和养分在剖面层次上无明显差异;土壤有机质含量较低,最高1.7871g/kg,最小0.201 7g/kg;土壤碳酸钙无明显的淋溶淀积,剖面中无淀积层;颗粒组成以2～0.02mm粒级的砂粒为主;土壤CEC集中分布在2.5～5cmol/kg,保肥性能差。通过诊断层和诊断特征分析,研究区土壤共分属1个土纲,1个亚纲,2个土类和4个亚类,其中剖面Ⅱ1属于弱盐潮湿砂质新成土,剖面Ⅱ5属于钠质潮湿砂质新成土,剖面Ⅲ4属于石灰潮湿砂质新成土,剖面Ⅵ4属于石灰干润砂质新成土。研究结果可为移民区的土壤资源综合评价、土壤适宜性评价及农、林、牧业合理布局提供依据。 相似文献
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Changes in the profile of gray forest soils on a tilled slope with manifestations of active erosion and a known duration of the plowing were analyzed. Factors determining the transformation of the composition and properties of individual parts of the soil profile were considered. Specific changes in the soil profile were revealed depending on the age of the plowland and its position in the relief. Tendencies of the agrogenic transformation of the lower horizons were found to depend on changes in the humus profile and the time of the soil existence in a relatively stable state. 相似文献
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等高犁耕朝向对紫色土坡面土壤再分布的影响 总被引：1，自引：0，他引：1
选择一块坡长15 m、坡度14.16%的坡地,采用磁性示踪法分析等高向下犁耕（向下坡方向翻垈）和等高向上犁耕（向上坡方向翻垈）的土壤再分布特征,利用模拟耕作（15次）检验两种等高犁耕的长期作用下对土壤剖面和微地貌演化的影响。结果表明:等高向下犁耕导致土壤发生向下坡移动,土壤位移量为15.62～28.70 kg/m,坡度对其影响不显著（p=0.93）;等高向上犁耕导致土壤同时发生向下坡和向上坡移动,土壤净位移量为-10.91～8.23 kg/m,坡度对其有显著影响（p < 0.001）,土壤净位移方向随着坡度的增大由向上坡转为向下坡,本研究条件下临界坡度为14%;等高向下犁耕15次后坡顶侵蚀深度是原土层深度的132%,耕作后土层深度与耕作深度相当,表明等高向下犁耕加速土壤侵蚀和促进母岩成土的双重作用共同维持着坡顶土层深度的稳定;等高向上犁耕15次后坡顶土层深度增加了12.7%,表明等高向上犁耕具有保护坡顶土层深度的作用。等高向上犁耕是一种防治类似紫色土的薄层土壤耕作侵蚀和土壤退化的有效措施。 相似文献
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《CATENA》1988,15(6):577-594
The influence of soil and environmental factors on water and salt dynamics in a typic Natraquoll of the center of the Flooding Pampa (Argentina) was studied. In phreatimeters, the water table reached the soil surface during floods, but in the soil profile it was never above the bottom of the B31 horizon (0.65 m). This horizon and the over-laying B22 one showed a permanent unsaturation. The A1, B1 and B21 horizons, however, often became saturated with water.The typical floods in the region are caused by the accumulation of rainwater on the previously saturated upper horizons. Simultaneously, phreatic water undergoes an abrupt increase in electrical conductivity (ECw). These saline peaks (ECw of up to 45.00 dS m−1) caused the immediate salinization of the deep horizons, probably by diffusion. The arrival of salts at the soil surface was episodic and by convection. However, salt leaching prevailed in the course of time in the upper horizons. The soil saturation extracts showed a balanced proportion of anions, but among cations, Na+ prevailed over Mg++, Ca++ and K+. Soil alkalinity was low and with some significant variations in the surface horizons, that depended on episodic salt rises or salt leaching processes. In the deep horizons soil remained permanently natric.This dynamic balance of water and salt showed that, in this part of the region, the soil profile exhibits two zones which are relatively independent of each other. Each represents different stages of the evolution as stated by Gedroiz's theory. The deep horizons undergo a continuous salinization and alkalinization process. The upper horizons tend to be similar to zonal soils. The slight halomorphism in this profile zone is due to the episodic salt rises. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(2):101-113
Abstract An experiment was conducted to help understand the contributions of different soil layers to soil fertility, plant growth, and response to fertilization. Douglas‐fir (Pseudotsuga menziesii) seedlings were used in a pot bioassay to delimit the effects of volcanic ash soils, urea fertilization at 100 and 200 ppm, and the technique of using undisturbed soil as a growth medium. Volcanic ash horizons contained more available phosphorus and mineralized more nitrogen than underlying horizons. Best seedling growth occurred in ash horizons fertilized with 200 ppm of urea‐N. Fertilization decreased soil pH, mycorrhizae formation and foliar‐P levels but increased foliar‐N. The technique of using undisturbed soil had little effect on seedling growth in the weak structured ash horizons but did decrease root weights in the moderate structured sub‐ash layers. 相似文献
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通过田间调查和土壤肥力指标分析，探讨了松辽平原玉米带黑土肥力退化的原因和机理。结果发现，现行的以小四轮拖拉机为主要动力的耕作制度下，土壤剖面中耕层与犁底层的界面为“波浪型”，而年年进行秋翻的玉米田，其耕层与梨底层的界面为“平面型”。而且两者耕层土壤的养分含量和理化性质等指标也有明显差异。研究还发现，现行的以无机氮磷肥为主的施肥制度和玉米连作种植制度对土壤养分平衡有很大影响。因此认为，现行的不合理的耕作、施肥及玉米连作制度是导致松辽平原玉米带黑土肥力退化主要原因。 相似文献