我国灌淤土的形成和分类

本文从全国范围内全国地研究了灌淤土的形成特点，主要表现在：（１）地面的抬升和耕层的加厚；（２）有机质及Ｎ、Ｐ、Ｋ等养分的增加；（３）土体含水量的提高；（４）可溶盐和石膏的淋洗；（５）碳酸盐和石膏的淋溶与补充；（６）灌淤层理的消失和土壤物理性状的改善等。总结了灌淤土的诊断层－灌淤表层的特点，阐明了灌淤土在土壤系统分类中的位置：灌淤土作为人为土壤，它与干旱土、潮湿土、始成土和新成土等其它土壤具有很大的     

不同土壤类型对硫酸钾镁肥中钾、镁、硫吸附特性研究

在水稻土、红壤、潮土中分别加入不同浓度的硫酸钾镁肥溶液,研究3种土壤在不同浓度硫酸钾镁肥下pH值的变化及对K、Mg、S吸附的能力。结果表明:在3种土壤中加入硫酸钾镁肥都使土壤pH值下降,下降速度是红壤>水稻土>潮土。3种土壤对K的吸附能力较强,可用一元线性方程拟合,在0~354 mg kg-1的K加入量范围内,吸附率在50.4%~74.1%;对S的相对吸附率居中,可用一元二次方程拟合,在0~311 mg kg-1的S加入量范围内,吸附率在35.6%~88.1%;对Mg的吸附能力极弱。3种土壤对K、S吸附能力大小顺序为:潮土>红壤>水稻,对镁吸附能力大小顺序为:潮土>水稻土>红壤。土壤田间施用硫酸钾镁肥量应根据不同土壤对养分的吸附能力大小进行相应的调整。     

黑龙港地区盐碱地演变的研究

应用１／１０万，１／２５万ＴＭ图象编制的黑龙港地区盐碱地分布图，代表了８０年代中后期该区盐碱分布的实际状况。经量算，盐碱地共有３９３４００ｈａ，其中轻盐化占一半以上，受自然因素，人为因素的综合影响，盐碱地处于明显的面积缩小，程度减轻的过程中，而且愈向平原上部愈益明显，到了滨海地带虽规律相似，但仍然盐重。由综合分析来看，盐渍扩大了农林牧业的适宜发展幅度，但同时地下水位下降，水资源日益紧缺又将带来生态     

The red soils, their origin, properties, use and management in Greece

Red soils in Greece are distributed throughout the country, but they occur more frequently in the southern provinces and constitute important soil resources supporting several land utilization types. They can be grouped into two categories: the autochthonous and the allochthonous. The former soils are found on hard limestone and on basic igneous rocks in sloping mountainous or hilly landscapes. Moreover, they can be found on mica schists and gneisses in locations adjacent to marble or calcareous mica schists.Allochthonous red soils are wide-spread on late Tertiary and Pleistocene surfaces in the lowlands. Many of these deep deposits have red strata, a few decimeters to several meters thick, or red-colored and fine-textured layers interbedded with light colored deposits of marl, or conglomerates and also with thick strata enriched with calcareous concretions. They are distributed in the thermo- and meso-mediterranean bioclimatic zones. These sites have a common feature, the gently sloping terrain that ensures efficient drainage.There are some differences in chemical and physical properties and in the clay mineralogy of the two groups of Greek red soils. Palygorskite is present in some soils developed on basic rocks; the clay minerals of the allochthonous soils on Pleistocene and late Pliocene seems to be mixed with micas in significant amounts.Soil forming factors required for the formation of red soils are: (a) parent material containing iron-bearing minerals, and rich in bases, (b) slope gradients and/or water permeabilities of the bed-rock securing excessive drainage and (c) vegetation cover that does not produce high amounts of, and deeply distributed organic matter.The allochthonous red soils have likely inherited their color from their parent materials that were transported from the originally formed residual soils on hard limestone. The soils retain the red color in the thermo-mediterranean zone only on sloping terrains. The soils on these landscapes are frequently stratified.The Greek red soils belong to the great groups of: Rhodoxeralfs, Palexeralfs, Xerochrepts, Orthents. Large portions of the allochthonous soils have been desertified or have been severely degraded and their extensive exploitation is not recommended.Soil management practices applied in the allochthonous soils include erosion control, preservation of organic matter, minimum tillage, split application of nitrogen using non-acidifying fertilizers, irrigation, soil water conservation and sheltered agriculture.     

Relationship between the characteristics of Mediterranean Red soils and the age of the geomorphological surfaces in central-western Spain

A study was conducted of the Mediterranean Red soils of a region in Central Western Spain with a goal of describing the relationship between their main characteristics and the age of the geomorphic surfaces over which they have developed. The main macromorphological characteristics of the soils were analyzed, with a statistical study of the analytical data on 70 samples of Mediterranean Red soils. The oldest surfaces contain Palexerults and Ultic Palexeralfs, Calcic Rhodoxeralfs, Calcic-vertic Palexeralfs, Typic Rhodoxeralfs, Typic Palexeralfs, Vertic Haploxeralfs and Typic Haploxeralfs have been observed in a chronosequence on terraces of the River Tormes. The soil typology changes with the age of the surfaces, from soils with a sharp textural contrast at the upper limit of the argillaceous horizon, with a dark red very clayey and very thick Bt horizon (on the oldest surface) to not very thick brown soils without a clear clay illuviation and with a lower content in clay (on the youngest surface).The effect of recent erosion on the morphology of the soils located on a single surface has caused new soils to form superimposed on pre-existing soils.     

可变电荷土壤吸附铜离子时氢离子的释放

可变电荷土壤吸附铜离子后 ,土壤的中和曲线上不出现pH突跃 ,而变成一条平缓变化的曲线。当土壤悬液的pH低于一定数值时 ,加入铜离子后不释放氢离子。该pH值与土壤中氧化铁的含量有关。氧化铁的含量越高 ,该pH值越高。对于大多数可变电荷土壤 ,此pH值为 4左右。对可变电荷土壤 ,pH值越接近 4,氢离子释放的快速过程越不明显。在pH 4左右 ,加入铜离子后 1 0分钟时 ,释放的氢离子量仅占 6 5分钟时释放量的 3 0 %左右。但当pH值高于 4 5时 ,在大多数情况下 ,加入铜离子后半分钟时释放的氢离子量即可占 6 5分钟时的 5 0 %以上。恒电荷土壤吸附铜离子时氢离子的释放速度比可变电荷土壤快得多。即使pH值低至 3 8,在加入铜离子后半分钟时氢离子的释放量即占 6 5分钟时的 5 6 %以上。可变电荷土壤吸附铜离子时的H/Cu比比恒电荷土壤大得多。当恒电荷土壤悬液中加入0 1mo1L- 1 NaNO3作支持电解质时 ,吸附铜离子时的H/Cu比增大。     

The effect of soil type on phosphorus sorption capacity and desorption dynamics in Irish grassland soils

Abstract. The phosphorus (P) sorption and desorption dynamics of eleven major agricultural grassland soil types in Ireland were examined using laboratory techniques, so that soils vulnerable to P loss might be identified. Desorption of P from soil using the iron-oxide paper strip test (Pfeo), water extractable P (Pw) and calcium chloride extractable P (Pcacl₂) depended on soil P status in all soils. However, soil types with high organic matter levels (OM), namely peat soils (%OM >30), had lower Pfeo and Pw but higher Pcacl₂ values compared to mineral soils at similar soil test P levels. Phosphorus sorption capacity remaining (PSCr) was measured using a single addition of P to soils and used to calculate total P sorption capacities (PSCt) and degree of P saturation (DPS). Phosphorus sorption capacities correlated negatively with % OM in soils indicating that OM may inhibit P sorption from solution to soil. High organic matter soils exhibited low P sorption capacities and poor P reserves (total P, oxalate extractable P) compared to mineral soils. Low P sorption capacities (PSCt) in peat soils were attributed to OM, which blocked or eliminated sorption sites with organic acids, therefore, P remained in the soil solution phase (Pcacl₂). In this work, peat and high organic matter soils exhibited P sorption and desorption characteristics which suggest that these soils may not be suitable for heavy applications of manure or fertilizer P owing to their low capacities for P sorption and storage.     

市域尺度的稀有濒危土壤类型的界定与评价——以郑州市为例

在当今世界城市化高速发展的背景下,土壤资源的保护也越来越受到人们的关注,土壤多样性骤减也成为了全球关注的焦点,界定和评价稀有濒危土壤对于保护土壤资源及其多样性具有非常重要的指导意义。本文以郑州市为例,应用土壤类型密度和土壤多样性两种多样性测度方法分别对郑州市1 km×1 km和5 km×5 km网格尺度下基于不同分类级别的土壤空间多样性分布格局进行了分析和定量化研究;利用1988、2001、2007和2013年4期遥感资料进行土地利用分类,结合基于第二次土壤普查的1∶20万郑州市土壤图,采用多时相连续对比法对郑州市近25年来土地利用变化对土壤的扰动情况进行了分析;结合土壤多样性方法和传统评价方法界定和评价了稀有濒危土壤。结果表明,郑州市土壤整体分布较为均匀,且随着分类单元级别的降低,构成组分多样性指数升高,即分类越细,土壤类型分布越均匀;1988~2013年郑州市土壤受到非农建设扰动剧烈,干扰比例为16.01%,随着时间的推移,土壤受扰动的速度是呈上升趋势的;稀有土属有16种,濒危土属有2种,稀有濒危土属有4种。截止2013年濒危土属整体受到扰动比例高达35.38%,而稀有土属受到扰动比例为8.76%。     

重庆缙云山典型植被原状土与重塑土抗剪强度研究

为了从土壤力学方面探索防治水土流失的途径与措施，该文采用直剪仪对重庆缙云山5种典型植被的原状土和重塑土抗剪强度进行试验测定。通过比较相同植被同干密度、同含水率的原状土与重塑土在同一垂直荷载下的剪切差异，分析了根(极细根)在土壤－根系复合体(原状土)中的作用。研究结果表明：原状土剪切位移小于重塑土；在相同垂直荷载作用下，同一植被原状土的抗剪强度大于与其同干密度、同含水率的重塑土。原状土的剪切破坏近似于塑性破坏，而重塑土则属于弹性破坏；原状土的抗剪强度与含根量呈正相关，并以此建立关于原状土的抗剪强度回归模型。     

Implications of iron solubilization on soil phosphorus release in seasonally flooded forests of the lower Orinoco River, Venezuela

The microbial reduction of Fe oxides is thought to contribute with the release of P in sedimentary environments. However, secondary reactions of the bioproduced Fe(II) with P in solution, can lead to a decrease in the soluble P concentration. In this study, we examined how the reduction of Fe(III) affects the soluble P concentration, when the soils of a seasonally flooded forest gradient are subjected to anaerobic conditions. Soil samples were collected during the dry season from two zones subjected to different flooding intensity: MAX and MIN zones that were inundated 8 and 2 months per year, respectively. When anaerobic conditions were applied to soils from both zones, a clear stimulatory effect on the Fe(III) reduction was observed. However, bioproduced Fe(II) underwent secondary chemical reactions, masking the extend of Fe(III) reduction of these soils. Iron was reduced mainly during the first 15 days of the anaerobic incubation and it was stimulated by a pulse of labile carbon. Iron dissolution did not lead to an increase of the soluble P content. However, in both zones P was high and positively correlated with Fe(II), implying that soil P mobilization was linked to Fe dissolution. In the MIN zone, soluble P concentration decreased, probably as a consequence of the secondary reactions of solubilized P with other non-redox sensitive soils elements. Fe solubilization also had an effect on the activity of acid phosphatase and consequently in the solubilization of P from the organic pool. In conclusion, the P cycle in these soils is strongly coupled to C and Fe cycles.     

Zinc Sorption in Selected Soils

Abstract

The adsorption of nutrient elements is one of the most important solid‐ and liquid‐phase interactions determining the retention and release of applied plant nutrients and the efficiency of fertilization. The study showed that the soils with high cation exchange capacity (CEC), CaCO₃, organic matter contents, and heavy texture adsorbed more zinc (Zn). The alkaline soils from Pakistan adsorbed more Zn than English acidic soils. Langmuir and Freundlich isotherm fit was excellent, and r² values for the Langmuir isotherm were highly significant (r²=0.84 to 0.99). The Langmuir b values, representing the adsorptive capacity of a soil, increased as the texture fineness increased in the soil, with increases in the concentration of adsorptive material (such as organic matter and CaCO₃) and with increases in CEC and pH. The alkaline soils from Pakistan had higher bonding energy constant and higher log Kf values than the acidic English soils. Sequential extraction of Zn in these soils showed that most of the Zn was held in CaCO₃ pool in the alkaline soils, whereas in acidic soils adsorbed Zn was in exchangeable form.     

陇东和陇中黑垆土的发生与演变

前人认为，我国黑垆土是现代草原环境条件下形成的。我们通过对陇东和陇中黑垆土理化性质分析，１４Ｃ年代和孢粉组成的测定。认为这里的黑垆土是由深色埋藏古土壤层和浅色表土覆盖层叠加构成。剖面呈两段性构造。古土壤层由晚更新世晚期开始发育，主要成壤于全新世中期，具有与现代成土环境不相符合的深厚腐殖质蓄积层，理化性质，孢粉成分等残遗埋藏特性。浅色表土层是全新世晚期气候传向旱型化条件下发育的土壤，其性质和现代成土     

磷对富硒赤红壤与红壤上小白菜硒吸收及土壤硒形态的影响

采用土培盆栽试验方法,研究了广西两种主要富硒土壤施入不同水平磷对小白菜硒吸收积累的影响及土壤硒形态转化规律,旨在为提高土壤有效形态硒含量及植物硒含量提供理论依据。试验采集广西具有代表性的富硒赤红壤(贵港市桂平市)和富硒红壤(桂林市永福县),设置4个磷梯度盆栽试验。结果表明:相同的磷处理在不同土壤上对小白菜硒吸收效果不同。在富硒赤红壤上低磷处理(P50,50 mg/kg)有利于小白菜地上部和地下部对硒的吸收;在富硒红壤上中磷处理(P110,110 mg/kg)小白菜地上部硒含量最高,地下部施入磷则硒含量均显著低于对照。同时,磷的施入对硒在小白菜体内的转运在两种土壤上也存在差异。在富硒赤红壤上当磷施入量在80 mg/kg以下时,磷的施入会抑制硒从地下部向地上部的转运;在富硒红壤上磷的施入则均能促进硒的转运;但二者均在中磷处理时达到峰值。植株体内硒含量间的差异取决于土壤有效形态硒含量。研究结果显示磷的施入均显著增加了土壤中水溶态和交换态硒的含量,且小白菜硒的含量与土壤中水溶态硒规律一致。研究还发现在两种土壤上不同磷处理对土壤硒形态转化规律不同,这为进一步研究磷与土壤硒间的互作关系提供了参考。     

几种有机酸对恒电荷和可变电荷土壤吸附Cu2+的影响

以恒电荷土壤(黄褐土和黄棕壤)和可变电荷土壤(红壤和砖红壤)为供试材料,研究了乙酸、草酸、酒石酸和柠檬酸对土壤吸附重金属铜离子(Cu2 )的影响。结果表明,在相同酒石酸浓度下,土壤对酒石酸的吸附量依次为黄棕壤(2 1 8mmolkg-1) >红壤(15 4mmolkg-1) >砖红壤(9 5mmolkg-1) ,土壤吸附有机酸后负电荷量增加,相同条件下增幅为砖红壤>红壤>黄棕壤;无有机酸配体时,供试土壤对Cu2 的吸附量为黄褐土>黄棕壤>砖红壤>红壤;加入有机酸时,随有机酸浓度增高,土壤对Cu2 的吸附一般表现为“峰”形曲线,峰所对应的有机酸浓度因有机酸类型而异,且随土壤可变电荷性质增强而增高;土壤吸附有机酸后对Cu2 的次级吸附不同于有机酸与铜共存时的竞争吸附,且因土壤性质表现迥异。这些结果意味着在存在有机酸配体的根际环境中,恒电荷土壤与可变电荷土壤对Cu2 的吸附明显不同,并将影响重金属离子在根际的转化与有效性     

Reisböden aus Kolluvium basaltischen Ursprungs im Hochland von Madagaskar

Paddy soils from basaltic colluvium in the Highland of Madagascar Three soils under lowland rice cultivation, found on the Highland of Madagascar, in the Vakinankaratra region, were investigated, in order to help understanding their ecology and to assess their fertility. The parent material of the three soils consists of basaltic colluvium. According to the FAO-UNESCO (1988), these soils have been classified as Ferralic Cambisol (D2) and Dystric Gleysol (D3 et D4). They are very poor in alkali cations, and rich in aluminium, iron and clay. The clay is mainly composed of gibbsite, kaolinite as well as of little amounts of goethite and quartz. This composition underlines the high degree of intensive soil weathering. The low fertility of the investigated soils is due to very low contents of available P, Ca, Mg, K and N, as well as to the high content of iron and manganese, which are toxic for rice plants under the anaerobic conditions of the soils during flooding. We therefore recommend to add to the soil beside NPK fertilizers, limestone powder in order to obtain a pH-value between 6 and 7. This will lead to an increase of Ca, Mg, and K as well as to a better plant availability of phosphorus and a decrease of the toxic effects of iron and manganese.     

Wheat and Rye Differ in Drymatter Partitioning,Shoot-Root Ratio and Water Use Efficiency Under Organic and Inorganic Soils

Shoot-root ratio (S:R), dry matter partitioning (DMP), and water use efficiency (WUE) response of wheat (Triticum aestivum L.) vs. rye (Secale cereale L.) was investigated under organic [organic compost (OC), Miracle Grow (MG), sunshine peat moss (SPM), and Garden Basic peat humus (GBPM)], and inorganic soils [canyon soil (CS) and amarillo soil (AS)] in pot experiment at Dryland Agriculture Institute, West Texas A&M University, College Station, Texas, USA, during winter 2009–2010. The experiment was performed in completely randomized design (CRD) with three repeats. The objective of this experiment was whether S:R, DMP, and WUE of wheat versus rye differ under organic and inorganic soils. The results revealed that both crops responded differently in terms of S:R, DMP, and WUE under different organic and inorganic soils. Wheat had higher WUE than rye at different growth stages. Among the soil types, the three organic soils (MG, SPM, and GBPS) had higher WUE than the two inorganic (CS and AS) soils. The higher WUE of both crops when grown in organic soils such as MG, SPM, and GBPS was due to the higher dry matter partitioning to shoots and roots. The total dry weight plant^?1 showed positive relationship with WUE.     

Phosphate solubilizing bacteria and fungi in desert soils: species,limitations and mechanisms

Desert soils are infertile, and the ability to improve them by P-fertilization is limited by the solubility of phosphate. We aimed to understand the function of phosphate solubilizing bacteria and the mechanisms behind phosphate solubilization in desert soils. Vegetated and barren desert soils, mine spoil and a fertile temperate grassland loam were sampled. Bacteria and fungi were isolated and identified, and their phosphate-solubilizing abilities were measured in vitro. The release of plant available PO₄, SO₄, NO₃ and NH₄ from desert soils did not compare with that of a grassland soil. Desert soils had substantially lower solubilization than grassland, 162 and 99–121 µg PO₄-P g^?1 dry soil, respectively. Phosphate-solubilizing bacteria and fungi were inhabiting the soils. Si addition increased phosphate solubilization of fungi by 50%. The isolated microbes were shown, using ³¹P nuclear magnetic resonance (NMR) analysis, to rapidly take-up both intracellular and extracellular phosphate during the phosphate solubilizing process. Desert soil had potentially active microbial populations that are capable to solubilize inorganic phosphorus; S and Si as the limiting factors. Acidification as the main mechanism to solubilize mineral phosphate was not as evident in our desert soils as in former studies dealing more fertile soils.     

Estimation of nitrogen and phosphorus losses to surface water and groundwater through the implementation of the SWAT model for Norwegian soils

Scope and Background

It is acknowledged that diffuse sources cause the most important nitrogen (N) and phosphorus (P) losses to the river system and substantially enrich the groundwater in nitrates. These losses arise primary from agricultural activities mainly fertilizer applications, and they are determined by soil attributes. In cold climates, winter conditions and freezing of soils may influence the infiltration capacity of the soil and thereby can have a serious effect on the partitioning of excess precipitation and subsequently on the soil and nutrient transportation. The purpose of this article is to investigate the behaviour of six widespread and different textured soil types, on nutrient (N, P) losses under cold climate conditions. The investigation was conducted in the Norwegian Vansjø-Hobølv catchment through the application of a physical model named Soil and Water Assessment Tool (SWAT), taking into consideration the additional aspect of freezing soils during winter, which distinguishes Scandinavian from other European soils.

Methods

SWAT is a physical river basin model that was developed for the U.S.D.A. Agricultural Research Service, by the Blackland Research Center in Texas. In the current modeling approach the catchment was divided into 43 Hydrologic Response Units (HRUs) which consist of different combinations of the existed landcover and soil types. Nitrogen and phosphorus losses arising from these HRUs were estimated for the period 1990–2001 through the simultaneous simulation of water and sediment processes that are closely linked to the nutrient processes. The model took into account soil temperature in order to quantify water and nutrient transport to deeper layers, considering negligible downward movement when the soil temperature was under 0°C. It also simulated the aboveground development of the snowpack and the snowmelt processes on a daily basis. The six different soil types were distinguished in two groups according to their similarity in texture and other physical properties, one group of fine-textured soils and a group of coarse soils. The results were evaluated for different crop cultivations (barley, oats and wheat) of the aforementioned soils. Finally, the model was calibrated and validated by comparing predicted results with measured data.

Results and Discussion

Fine-textured soils caused significant runoff, sediment, total nitrogen (TN) and total phosphorus (TP) yields to the river system while coarser soils were characterized by high water drainage and nitrates leaching. The first soil group caused a mean of 517 mm of runoff in annual basis, 200 mm higher than this arising from coarse soils. Moreover, 3 tonnes of sediments per hectare, 24.6 kgN/ha and 0.54 kgP/ha were lost annually to surface water from fine soils while the average respective losses originating from coarse soils were only 1.3 tn of sediments/ha, 13.6kgN/ha and 0.17kgP/ha. The sensitivity ranking of the soil types to TN and TP losses was silty-clay-loam>silty-loam>clay>loamy>sandy-loam>sandy. An average of 277 mm of water was percolated annually under the bottom of the soil profile in coarse soils causing the additional leaching of 5.6 kgN-NO₃/ha whereas the losses originating from fine-textured soils were 153 mm and 2.5 kg/ha respectively. According to their sensitivity in nitrates leaching, the six soil types were ranked in the following order: sandy>loamy>sandy-loam>silty-loam>silty-clay-loam>clay.

Conclusions and Perspectives

The results showed that even though under cold climate conditions, with monthly periods of average air-temperatures below zero, the overall amounts of annual TN and TP losses to surface waters as well as nitrates leaching to groundwater were considerable. This demonstrates that the cold climate conditions did not affect the long-term behavior of the six widespread Norwegian soils, which on an annual basis responded similarly to the respective European soils. According to the model’s estimations, infiltration with N and P transport still occur in wintertime, and comparing to other studies that reported similar results, different possible explanations were considered. The results demonstrate the need of considering the soil differentiation in Scandinavian countries similarly to the rest of Europe in order to apply mitigation measures against nitrogen and phosphorus losses to surface and groundwater.

     

Greenhouse gas emissions from farmed organic soils: a review

Abstract. The large boreal peatland ecosystems sequester carbon and nitrogen from the atmosphere due to a low oxygen pressure in waterlogged peat. Consequently they are sinks for CO₂ and strong emitters of CH₄. Drainage and cultivation of peatlands allows oxygen to enter the soil, which initiates decomposition of the stored organic material, and in turn CO₂ and N₂O emissions increase while CH₄ emissions decrease. Compared to undrained peat, draining of organic soils for agricultural purposes increases the emissions of greenhouse gases (CO₂, CH₄, and N₂O) by roughly 1t CO₂ equivalents/ha per year. Although farmed organic soils in most European countries represent a minor part of the total agricultural area, these soils contribute significantly to national greenhouse gas budgets. Consequently, farmed organic soils are potential targets for policy makers in search of socially acceptable and economically cost-efficient measures to mitigate climate gas emissions from agriculture. Despite a scarcity of knowledge about greenhouse gas emissions from these soils, this paper addresses the emissions and possible control of the three greenhouse gases by different managements of organic soils. More precise information is needed regarding the present trace gas fluxes from these soils, as well as predictions of future emissions under alternative management regimes, before any definite policies can be devised.     

我国菜园土壤中某些重金属元素的含量与分布

本文对我国各主要起源母土上发育的厚熟土、不同熟化程度的菜园土以及相对应的粮田土壤３７个剖面中某些重金属元素的全量及有效态含量进行了研究，结果表明：菜园土壤随种菜历史的延长、熟化程度的增加、重金属元素Ｚｎ、Ｃｕ、Ｐｂ的含量有明显增高的趋势。元素在剖面中的分布以表层含量最高，向下递减。厚熟土由于具有较厚的熟化表层，元素全量及有效态含量在０－４０ｃｍ土层中均较高，多在过渡层之下出现突然降低的转折；中度和