中国亚热带红壤团聚体稳定性与土壤化学性质的关系

The stability of aggregates in the surface soil is crucial to soil erosion and runoff generation. Thus, to understand the stability and the breakdown mechanisms of soil aggregates as well as the relationship between aggregate stability and selected soil chemical properties, such as different forms of Fe and Al oxides, organic matter, CEC and clay content, the aggregates of slightly and severely eroded red soils derived from Quaternary red clay in subtropical China were analyzed using the routine wet sieving and the Le Bissonnais methods. The results indicated that the aggregates of the severely eroded soils were more stable than those of the slightly eroded soils. Different aggregate breakdown mechanisms resulted in different particle size distribution. The slaking from entrapped air in aggregates severely destroyed the soil aggregates, especially in the slightly eroded soils. Meanwhile, mechanical breakdown and microcracking had little effect on the aggregates compared to slaking. The fragments resulting from slaking were mainly microaggregates that increased in size with increasing clay content. The main fragment size of the slightly eroded soils was 1.0-0.2 mm, while for the severely eroded soils it was 5.0-2.0 mm and 1.0-0.5 mm. Overall, more than 20% of the fragments were smaller than 0.2 mm. In addition, aggregate stability was positively and often significantly correlated with Fe_d, Al_d, Fe_o and clay content, but significantly and negatively correlated to SOC.     

土壤母质与茶叶质量的关系初探

Six tea plantations with different soil-forming parent naterials,the same tea variety and tea age and similar landforms and management were selected to conduct a systematic study on the realtionship between soil properties and tea quality.The results showed that the quality of tea grown on the soil derived from dolomites,Quaternary red clays,were inferior.Further study showed that sandy soils were beneficial to improving amino acid content of tea ,and clayey soils made it decrease;high content of bases might decrease the contents of tea polypenols,caffeine,water extracts,but promote the content of amino acds;available phosphorous was significantly positively correlated with water extracts ,but significantly negatively correlated with caffeine;slowly avaiable potassium was positively correlated with amino acid content .Soil parent materials should be regarded as an important factor in eveluating the adatability of tea to soils.     

Aggregate Stability and Its Relationship with Some ChemicalProperties of Red Soils in Subtropical China

The stability of aggregates in the surface soil is crucial to soil erosion and runoff generation. Thus, to understand the stability and the breakdown mechanisms of soil aggregates as well as the relationship between aggregate stability and selected soil chemical properties, such as different forms of Fe and A1 oxides, organic matter, CEC and clay content, the aggregates of slightly and severely eroded red soils derived from Quaternary red clay in subtropical China were analyzed using the routine wet sieving and the Le Bissonnais methods. The results indicated that the aggregates of the severely eroded soils were more stable than those of the slightly eroded soils. Different aggregate breakdown mechanisms resulted in different particle size distribution. The slaking from entrapped air in aggregates severely destroyed the soil aggregates,especially in the slightly eroded soils. Meanwhile, mechanical breakdown and microcracking had little effect on the aggregates compared to slaking. The fragments resulting from slaking were mainly microaggregates that increased in size with increasing clay content. The main fragment size of the slightly eroded soils was 1.0-0.2 mm, while for the severely eroded soils it was 5.0-2.0 mm and 1.0-0.5 mm. Overall, more than 20% of the fragments were smaller than 0.2 mm.In addition, aggregate stability was positively and often significantly correlated with Fed, Ald, Feo and clay content, but significantly and negatively correlated to SOC.     

土壤持水特性参数与土壤质地尺度关系的联合多重分形分析

Soil water-retention characteristics at measurement scales are generally different from those at application scales, and there is scale disparity between them and soil physical properties. The relationships between two water-retention parameters, the scaling parameter related to the inverse of the air-entry pressure (αvG, cm-1) and the curve shape factor related to soil pore-size distribution (n) of the van Genuchten water-retention equation, and soil texture (sand, silt, and clay contents) were examined at multiple scales. One hundred twenty-eight undisturbed soil samples were collected from a 640-m transect located in Fuxin, China. Soil water-retention curves were measured and the van Genuchten parameters were obtained by curve fitting. The relationships between the two parameters and soil texture at the observed scale and at multiple scales were evaluated using Pearson correlation and joint multifractal analyses, respectively. The results of Pearson correlation analysis showed that the parameter αvG was significantly correlated with sand, silt, and clay contents at the observed scale. Joint multifractal analyses, however, indicated that the parameter αvG was not correlated with silt and sand contents at multiple scales. The parameter n was positively correlated with clay content at multiple scales. Sand content was significantly correlated with the parameter n at the observed scale but not at multiple scales. Clay contents were strongly correlated to both water-retention parameters because clay content was relatively low in the soil studied, indicating that water retention was dominated by clay content in the field of this study at all scales. These suggested that multiple-scale analyses were necessary to fully grasp the spatial variability of soil water-retention characteristics.     

美国8种土壤的活性腐植酸和难溶性钙质腐植酸盐中碳官能团的特性分析

Solid state13C nuclear magnetic resonance(NMR)spectroscopy is a common tool to study the structure of soil humic fractions;however,knowledge regarding carbon structural relationships in humic fractions is limited.In this study,mobile humic acid(MHA)and recalcitrant calcium humate(CaHA)fractions were extracted from eight soils collected from six US states and representing a variety of soils and ecoregions,characterized by this spectroscopic technique and analyzed for statistical significance at P≤0.05.We found that the abundances of COO and N–C=O functional groups in the MHA fractions were negatively correlated to soil sand content,but were positively correlated to silt,total N and soil organic carbon contents.In contrast,the abundances of the COO and N–C=O functional groups were only positively correlated to the content of clay in the CaHA fractions,indicating that the two humic fractions were associated with diferent soil components.The two13C NMR peaks representing alkyls and OCH3/NCH were negatively correlated to the peaks representing aromatics,aromatic C–O and N–C=O/COO.Comparison of the sets of data from13C NMR spectroscopy and ultrahigh resolution mass spectrometry revealed that the aromatic components identified by the two methods were highly consistent.The comparison further revealed that protein in MHA was associated with,or bound to,the nonpolar alkyl groups,but a component competitively against(or complementary to)aromatic groups in the MHA composition.These observations provided insight on the internal correlations of the functional groups of soil humic fractions.     

成土作用及人为活动对水耕人为土钙镁行为的影响

The formation of Stagnic Anthrosols is closely related to rice planting and parent materials. Six representative pedons,two from each of three Stagnic Anthrosol subgroups, Vertic Haplic-, Vertic Gleyic-, and Sulfic Gleyic-Stagnic Anthrosols,from different parent materials and soil formation processes, from Liaoning Province, China, were selected and used along with additional supporting data to assess the potential impact in each soil subgroup combination of both pedogenic and anthropogenic factors on the migration and geochemical characteristics of calcium (Ca) and magnesium (Mg) and their relations to soil particle-size composition. Results revealed that exchangeable Mg was correlated positively with clay and silt content, but negatively with sand content, suggesting that clay and silt could retain more exchangeable Mg than sand. Also, in the six pedons exchangeable Ca/Mg ratios generally decreased with depth, which was most likely due to the preferential retention of Mg below the Apl horizon and the effects of bio-cycling in rice-soil systems. The pedons with high pH had smaller exchangeable Ca/Mg ratios than those with low pH. Thus, it was concluded that exchangeable Ca/Mg ratios could be helpful in classification of Stagnic Anthrosols.     

植被覆盖和雨强对附着在沉积物上的养分流失, 泥沙颗粒组成及体积分形维数的影响

Vegetation and rainfall are two important factors affecting soil erosion and thus resulting in nutrient loss in the Chinese Loess Plateau.A field experiment was conducted to investigate the effects of rainfall intensities(60,100 and 140 mm h-1) and vegetation(Caragana korshinskii) coverages(0%,30% and 80%) on soil loss,nutrient loss,and the composition and volume fractal dimension of eroded sediment particles under simulated rainfall conditions.The results showed that vegetation cover,rainfall intensity and their interaction all had significant effects on sediment transport and the sedimentbound nutrient loss.Higher rainfall intensity and lower coverage led to higher sediment and nutrient losses.Positive linear relationships were observed between soil loss and nutrient loss.The treatments showed more significant effects on the enrichment ratio(ER) of nitrogen(ERN) than organic matter(EROM) and phosphorus(ERP).Compared with the original surface soil,the eroded sediment contained more fine particles.Under the same coverage,the clay content significantly decreased with increasing rainfall intensity.The ER of sediment-bound nutrients was positively correlated with that of clay,suggesting that the clay fraction was preferentially eroded and soil nutrients were mainly adsorbed onto or contained within this fraction.There were increments in the fractal dimension of the sediment particles compared to that of the original surface soil.Moreover,the fractal dimension was positively correlated with clay,silt,and sediment-bound OM,N,and P contents,whereas it was negatively correlated with sand content.This study demonstrated that fractal dimension analysis can be used to characterize differences in particle-size distribution and nutrient loss associated with soil erosion.     

Clay Addition to Sandy Soil——Influence of Clay Type and Size on Nutrient Availability in Sandy Soils Amended with Residues Differing in C/N ratio

Addition of clay-rich subsoil to sandy soil results in heterogeneous soil with clay peds(2-mm) or finely ground( 2 mm) clay soil(FG), which may affect the nutrient availability. The aim of this study was to assess the effect of clay soil particle size(FG or peds)and properties on nutrient availability and organic C binding in sandy soil after addition of residues with low(young kikuyu grass,KG) or high(faba bean, FB) C/N ratio. Two clay soils with high and low smectite percentage, clay and exchangeable Fe and Al were added to a sandy soil at a rate of 20%(weight/weight) either as FG or peds. Over 45 d, available N and P as well as microbial biomass N and P concentrations and cumulative respiration were greater in soils with residues of KG than FB. For soils with KG residues,clay addition increased available N and initial microbial biomass C and N concentrations, but decreased cumulative respiration and P availability compared to sandy soil without clay. Differences in measured parameters between clay type and size were inconsistent and varied with time except the increase in total organic C in the 53 μm fraction during the experiment, which was greater for soils with FG than with peds. We concluded that the high exchangeable Fe and Al concentrations in the low-smectite clay soil can compensate a lower clay concentration and proportion of smectite with respect to binding of organic matter and nutrients.     

内蒙古草原碳、氮储量:气候与土壤质地的关系

Understanding the spatial variability of soil carbon(C) storage and its relationship with climate and soil texture is critical for developing regional C models and for predicting the potential impact of climate change on soil C storage. On the basis of soil data from a transect across the Inner Mongolian grasslands, we determined the quantitative relationships of C and nitrogen(N) in bulk soil and particle-size fractions(sand, silt, and clay) with climate and soil texture to evaluate the major factors controlling soil C and N storage and to predict the effect of climate changes on soil C and N storage. The contents of C and N in the bulk soil and the different fractions in the 0–20 and 20–40 cm soil layers were positively correlated with the mean annual precipitation(MAP) and negatively correlated with the mean annual temperature(MAT). The responses of C storage in the soil and particle-size fractions to MAP and MAT were more sensitive in the 0–20 cm than in the 20–40 cm soil layer. Although MAP and MAT were both important factors influencing soil C storage, the models that include only MAP could well explain the variation in soil C storage in the Inner Mongolian grasslands. Because of the high correlation between MAP and MAT in the region, the models including MAT did not significantly enhance the model precision. Moreover, the contribution of the fine fraction(silt and clay) to the variation in soil C storage was rather small because of the very low fine fraction content in the Inner Mongolian grasslands.     

湿润速率和粘粒含量对红壤沟间侵蚀的影响

An aggregate stability test and a simulated rainfall test were conducted on four representative Ultisols from southeastern China. The soils selected, with clay contents ranging between 117 and 580 g kg-1 , were derived from shale and Quaternary red clay. The stability of aggregates (2–5 mm in diameter) obtained from the soil samples were determined by the Le Bissonnais method. For determination of infiltration, runoff, and erosion, the soil samples were packed in 30 cm × 60 cm trays, wetted at rates of 2, 10, and 60 mm h-1 , and then exposed to simulated rainfall at 60 mm h-1 for 1 h. The results indicated that both aggregate stability and slaking caused by fast wetting increased with increasing clay content. The effect of wetting rate (WR) on infiltration and seal formation varied with clay contents. In the soil with low clay content (sandy loam), the infiltration rate was affected slightly by WR due to low aggregate stability and slaking. In the soils with medium clay content (silt clay loam and clay), WR affected infiltration significantly due to the high aggregate slaking force. In the soil with high clay content, the effect of WR on infiltration was significant, but not as evident as in the soils with medium clay content, which may be related to high aggregate stability by wetting partially compensating for slaking force. The effect of WR on soil loss was similar to that of runoff, but more pronounced. The findings from this study indicated that the relationship between wetting rate and clay content should be considered when predicting interrill erosion in Ultisols.     

灌区土壤盐分空间变异及多因素响应关系

[目的]研究土壤含盐量空间特征和分布格局,分析土壤盐分空间格局与地下水、土壤物理特性参数间的空间响应关系,为灌区盐渍化防控提供理论依据。[方法]以黄河南岸灌区吉格斯太灌域为例,网格化布点,分层采样测定土壤含盐量、表层土壤含水量、颗粒组成、干容重并换算热容量及导热率,同步监测地下水埋深及含盐量,采用经典统计方法和地统计方法分析土壤含盐量空间分布特征及其与物理特性和地下水等因素间的空间相关性。[结果]灌域处于非盐化—轻度盐化状态,土壤含盐量呈中等空间变异程度,总体呈现相对独立的随机分布,空间结构特征可以用高斯模型和指数模型描述。土壤含盐量与地下水埋深呈显著负相关,与地下水含盐量呈显著正相关,地下水埋深1.6 m区域发生轻度盐渍化风险较高。0—20 cm土壤含盐量与黏粒含量、容重、含水量、导热率及热容量显著空间正相关,相关范围约2～6 km;与砂粒含量呈显著空间负相关,相关范围约2～4 km。20—60 cm土壤盐分与0—20 cm土壤黏粒、砂粒含量、导热率、热容量及含水量呈显著相关,相关范围与土壤表层略有差异。[结论]黏粒含量较高,含水率较大,地下水埋深1.6 m的区域是灌域盐渍化防控的重点区域。     

砂姜黑土钙质结核剖面分布特征及其对土壤持水性的影响

钙质结核是砂姜黑土重要的成土特征,直接影响土壤结构和水分运移,但目前关于钙质结核对土壤持水性作用机制的研究主要集中在实验室尺度,而且报道较少.基于此,该研究在田间尺度上研究了钙质结核剖面垂直分布特征及其对土壤持水性的影响.结果表明:钙质结核主要分布在20 cm以下的土层,其含量和粒径均随土层深度的增加呈现增大趋势,>8...     

三峡库区植物篱系统土壤颗粒分形特征及其与土壤理化性质的关系

在对长江三峡库区坡耕地植物篱系统调查样地土壤样品颗粒分析的基础上,对植物篱系统内土壤颗粒分布及土壤分形维数与土壤物理性质和土壤养分含量的关系进行了研究,结果表明:（1）乔木类、草本类和灌木类植物篱带间坡耕地土壤砂粒含量比其对应的植物篱带内土壤沙砾平均含量分别高10.4%,13.7%和9.2%;而黏粒含量在植物篱带内富集,其平均含量比植物篱带间坡耕地土壤黏粒含量分别高14.3%,19.5%和10.7%;（2）土壤分形维数与土壤黏粒和土壤粉粒含量具有显著（P < 0.01）的正相关关系,而与土壤砂粒含量显著负相关。（3）土壤分形维数与土壤孔隙度、含水量和土壤饱和导水率极显著正相关,而土壤容重与分形维数呈显著负相关关系。土壤分形维数与土壤有机质、土壤全氮、土壤有效氮、土壤全钾、土壤有效钾、土壤全磷含量和阳离子交换量显著相关,而土壤有效磷含量和土壤分形维数相关性不显著。     

我国北方半干旱地区土壤的沙漠化演变过程与机制

土地沙漠化是我国北方干旱半干旱地区土地退化最严重的类型之一。但迄今为止,人们对这一地区土地沙漠化过程中土壤沙化过程和机制的了解还不够透彻。2002-2003年,我们在科尔沁沙地选择具有明显沙漠化梯度的一个区域,调查和研究了土壤沙漠化演变过程和机制。结果表明,在科尔沁沙地,不同粒径土壤颗粒的理化特性具有较大差异,其中土壤粘粉粒和粗沙相比,具有较低的土壤容重和较高的土壤结持力、起沙风速、毛管持水力和养分含量。从土壤粘粉粒到粗沙,容重增加了10.32%,结持力、毛管持水量、有机碳、全氮分别下降了99.15%,51.23%,83.73%和80.24%。沙漠化过程中,土壤的理化性质随着土地沙漠化程度的增强而明显恶化。和非沙漠化土地相比,严重沙漠化土地的土壤粗沙含量、非毛管孔隙度和容重分别增加了35.04%,117.50%和21.7%,细沙含量、粘粉粒含量、总孔隙度、毛管孔隙度、田间持水量、毛管持水量、土壤有机碳、全氮、全磷、有效氮和有效磷分别下降了77.78%,70.00%,15.38%,27.49%,54.34%,37.54%,64.15%,70.77%,65.90%,66.32%和50.59%。相关分析结果表明,沙漠化过程中,土壤有机碳、全氮、全磷、土壤含水量和土壤结持力的变化与土壤粘粉粒的减少呈明显正相关,与土壤粗沙含量的增加呈明显负相关。这说明,沙漠化过程中,由于风蚀而导致的富含养分和具有较高持水能力的土壤细颗粒的损失,是沙漠化过程中土壤退化的主要机制。     

苎麻对红壤旱地土壤团聚体及其特性的影响

采用干、湿筛法研究了种植苎麻和花生对红壤旱地土壤团聚体及其特性的影响,并比较分析了土壤团聚体及土壤理化性质与地表径流和土壤侵蚀量的关系。结果表明:(1)与花生地相比,苎麻地有机质、田间持水量、总孔隙度、沙粒分别升高了28.44%,10.06%,5.65%和53.13%,土壤容重、粉粒和黏粒则分别降低了7.20%,14.85%和34.95%,均达显著性差异水平(p0.05)。(2)团聚体平均重量直径(MWD)、稳定性指数(ASI)显著升高(p0.01),苎麻地土壤团聚体稳定性优于花生地;(3)两处理均以0.25~1mm粒径团聚体保存几率最大,抗水蚀能力最强。(4)地表径流量和土壤侵蚀量与土壤有机质、沙粒含量、1mm的干团聚体、0.5mm的水稳性团聚体、MWD以及ASI呈极显著负相关关系(p0.01),而与粉粒、黏粒、0.25mm干团聚体、0.053mm的水稳性团聚体、呈极显著正相关关系(p0.01)。     

新型土壤改良剂Arkadolith对沙质土壤主要物理性质的影响

通过室内盆栽试验,研究了新型土壤改良剂Arkadolith不同施用率（0,4%,8%,12%,16%）对风沙土主要物理性质的影响。结果表明:施加土壤改良剂Arkadolith降低了土壤容重和比重,提高了土壤孔隙度与孔隙比;能明显降低沙质土壤中砂粒的含量,粒级0.05～0.01 mm的粉粒比对照降低12.5%～18.3%,提高了黏粒和物理性黏粒的含量,使原来无黏粒的沙土出现了少量的黏粒,<0.01 mm物理性黏粒增加3.3～4.0倍。施加土壤改良剂Arkadolith改良了土壤结构,4种处理土壤各粒级团聚体相较于对照均有明显的增加,以>5 mm和>0.25 mm两者为例,增加幅度分别为28.84%～66.67%和28.21%～63.49%。同时土壤改良剂Arkadolith的施用改善了沙土的持水能力和供水水平,且持水能力表现为随着改良剂施用率增加而增强。这些指标表明,施用土壤改良剂Arkadolith能有效地改善沙质土壤物理特性,增强沙土的保水能力。     

矿区生态修复过程中不同立地类型土壤水动力学特性

[目的]揭示矿区不同立地土壤水动力学特性及其影响因素,为矿区生态环境恢复治理提供科学依据。[方法]基于矿区不同立地类型土壤水分特征曲线、非饱和导水率、孔隙度与紧实度等监测试验,揭示不同立地类型土壤持水性、有效水含量和导水特性等变化规律。[结果]土壤持水性和供水性在受损区<修复3a区<修复5a区<修复10a区<修复15a区<未干扰区,但修复区20—40cm土壤持水性、供水性较0—20cm土壤低,修复效果不明显;土壤结构改善效果遵循受损区<修复区<未干扰区的变化规律,且修复区亚表层土壤结构改善效果不明显。采用指数函数拟合吸力和非饱和导水率效果较好(r2>0.95),相同吸力下,容重大而非饱和导水率较小;非饱和导水率和容重呈负相关,和孔隙度呈正相关且相关性随吸力增加降低。矿区0—20cm易有效含水量呈现受损区<修复3a区<修复5a区<修复10a区<未干扰区<修复15a区,但修复区20—40cm土层易有效水含量较0—20cm小。[结论]土壤易有效水含量和容重、紧实度呈负相关关系,与总孔隙度、黏粒含量呈正相关关系。修复后土壤结构有所改善,持蓄调节水分能力有所提高。     

滇东喀斯特山原红壤退化过程中剖面颗粒分形特征

山原红壤是在古气候影响下残存于高原面的古红土,近年来退化严重。为认识山原红壤的质地和退化程度,以滇东山原红壤典型发育地带为研究对象,对灌丛、草地、松林、红裸土剖面的土壤颗粒分形特征进行研究分析。结果表明:土壤颗粒分形维数在2.734~2.829,土壤质地整体属于粉质粘壤土。随着深度的增加,灌丛、草地、松林的土壤分形维数逐渐变大,红裸土则呈现出相反的规律。黏粒含量与土壤颗粒分形维数在土壤剖面上表现出相同的变化规律,砂粒和粉粒规律不明显。分形维数与黏粒呈极显著正相关,主要由黏粒决定,与粗砂呈负相关,与细砂和粉粒呈正相关,但均不显著（p < 0.05）。分形维数与有机质呈正相关,与速效钾、速效磷、硝态氮呈负相关,均不显著（p < 0.05）。分形维数可以表征山原红壤退化过程中剖面质地的均一程度,作为判断土壤质地差异的重要指标,在一定程度也可以反映土壤的肥力特征。     

The Influence on Yield of Mushrooms (Agaricus bisporus) of the Casing Layer Pore Space Volume and Ease of Water Uptake

Casing is the ‘soil’ layer applied to compost on which primordia known as pins form after airing, a proportion of which develop into mushrooms during several flushes or bursts of growth, usually occurring every six to ten days. Brown sphagnum moss peat casing (SP) was compared with black fen peat casing (BP) and gave significantly higher yields for each of five, potentially high-yielding composts, but a similar yield for a single potentially low-yielding compost. At the end of cropping, BP casing, which had poor structure, had permanently shrunk to a larger degree than SP casing. BP casing was also found more difficult to re-hydrate on the high-yielding composts and from the second flush onwards, these mushrooms had a progressively higher dry matter. This contrasted with those from the SP casing which had a progressively lower dry matter. In Northern Ireland, in the last decade, progressively more BP casing has been used. The likelihood that this has lowered potential yields is discussed.

In another experiment, eight casings were tested on a single compost, four contained 50% SP casing (as used for the control) plus 50% spent-mushroom-compost (SMC) the latter having been eluted with either water or citric acid and then either pasteurized or not. The three casings which comprised eluted SMC only were clay-like in consistency and mixing them with SP casing reduced pore-space. All casings initially contained a similar moisture percentage (v/v); however, during cropping they demonstrated a wide range of resistance to being re-hydrated at watering. This repellence was scored ‘blind’ and found to be inversely correlated with a measure of casing water uptake potential and with the percentage by volume of pore space contained within the casing, both measurements having been made at the start of the experiment. Water repellence was significantly, inversely correlated with mushroom moisture content and with yield. Casing water uptake potential and pore space were significantly correlated with mushroom moisture content and with yield. Yield was significantly correlated with mushroom moisture content and also with the number of primordia developing to pea size.     

Erosional impacts on soil properties and corn yield on Alfisols in central Ohio

Accelerated soil erosion can impact upon agronomic productivity by reducing topsoil depth (TSD), decreasing plant available water capacity and creating nutrient imbalance in soil and within plant. Research information on soil‐specific cause – effect relationship is needed to develop management strategies for restoring productivity of eroded soils. Therefore, two field experiments were established on Alfisols in central Ohio to quantify erosion‐induced changes in soil properties and assess their effects on corn growth and yield. Experiment 1 involved studying the effects of past erosion on soil properties and corn yield on field runoff plots where soil was severely eroded and comparing it with that on adjacent slightly eroded soil. In addition, soil properties and corn grain yield in runoff plots were compared on side‐slopes with that on toe‐slopes or depositional sites. Experiment 2 involved relating corn growth and yield to topsoil depth on a sloping land. With recommended rates of fertilizer application, corn grain yield did not differ among erosional phases. Fertilizer application masked the adverse effects of erosion on corn yield. Corn grain yield on depositional sites was about 50 per cent more than that on side‐slope position. Corn plants on the side‐slope positions exhibited symptoms of nutrient deficiency, and the ear leaves contained significantly lower concentrations of P and Mg and higher concentrations of Mn and K than those grown on depositional sites. Corn grain yield in experiment 2 was positively correlated with the TSD. Soil in the depositional site contained significantly more sand and silt and less clay than that on the side‐slope position. There were also differences in soil properties among erosional phases. The soil organic carbon (SOC) content was 19\7 g kg⁻¹ in slightly eroded compared with 15\1 g kg⁻¹ in severely eroded sites. Aggregate stability and the mean weight diameter (MWD) were also significantly more in slightly eroded than severely eroded soils. Adverse effects of severe erosion on soil quality were related to reduction in soil water retention, and decrease in soil concentration of N and P, and increase in those of K, Ca and Mg. Severe erosion increased leaf nutrient contents of K, Mn and Fe and decreased those of Ca and Mg. Corn grain yield was positively correlated with aggregation, silt and soil N contents. It was also negatively correlated with leaf content of Fe. Copyright © 2000 John Wiley & Sons, Ltd.