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1.
红壤性水稻土的形成过程特点及其肥力演变   总被引:2,自引:4,他引:2       下载免费PDF全文
红壤性水稻土形成过程中,物质转化和移动是在淹水还原占优势的周期性干湿交替和氧化还原交替条件下进行的。它不仅加速有机质的积累,而且E.H./T.H.值和H.A./F.A.比值增大。复盐基作用使酸性和盐基高度不饱和的红壤,发育成为盐基饱和度相当高的红壤性水稻土。氧化还原和络合等淋移作用,导致化学元素在土体中重新分配,红壤富铝化过程减缓,有利于水稻土的培肥熟化。土壤物理性质和剖面特征也发生相应的改变,形成具有核块状结构、胶膜和铁、锰斑淀积明显的渗积层(P层);结构改善;肥力不断提高。上述变化与植稻年限呈正相关趋势,可把红壤性水稻土形成过程划分为雏型淹育型阶段;过渡渗育型阶段;十年左右初步形成具有水稻土基本属性的渗育型水稻土。  相似文献   

2.
玄武岩发育的几种红壤的矿物特征   总被引:5,自引:0,他引:5       下载免费PDF全文
蒋梅茵  杨德湧 《土壤学报》1991,28(3):268-275
本文主要研究不同生物气候条件下由玄武岩母质发育的红壤、赤红壤和砖红壤的理化性质及矿物组成。粘粒中氧化铁的含量都很高,为16.98±0.83%。砖红壤与赤红壤粘粒中高岭石与非晶物质的含量相近,它们之间的差异是赤红壤中没有三水铝石,而含有7—11%蒙皂石。红壤粘粒中高岭石和非晶物质的含量都低于砖红壤和赤红壤,而水云母和蒙皂石的含量较高,也没有三水铝石。粘粒含量、阳离子交换量、硅铝率、硅铁铝率、铁的游离度和风化淋溶系数等都反映了土壤风化程度上的差异,它与水热条件特别是年均温和积温有关,进一步说明生物气候因素引起的土壤性质及矿物组成变化比其它因素强烈。砖红壤与砖红壤性水稻土的差异是在氧化铁形态上;红壤与红壤性水稻土相比,后者粘粒中蒙皂石含量略高,水云母含量略低。  相似文献   

3.
不同时期形成的铁质富铝土特性及其在发生上的意义   总被引:2,自引:0,他引:2  
本文在其他成土因素相对一致的前提下研究时间因素对土壤性状的影响,并以此为依据探讨分类中的一些问题.随成土时间变长(Q4-Q1),土壤的微形态特征,化学性质和粘土矿物组成都发生较大变化.如原生矿物含量减少;三水铝石逐渐增多;高岭石结晶程度变高;粘粒硅铝率和交换量分别由1.91、57.5减至1.25、12.9;游离铁含量增加.分析资料的统计结果表明:成土时间对土壤性状的影响一般小于生物气候的影响;全新世火山灰发育的土壤的粘土矿物、交换量、游离铁含量等性状与红壤截然不同,不应归属于红壤而应在高级分类单元中加以区分;许多在发生上有意义的指标,如硅铝率等,由时间因素引起的变化(Q3-Q1)已超过了同一母质发育的不同土类间的变化,因此把Q3-Q1玄武岩发育的高富铝土归属于同一土属也是不妥的.  相似文献   

4.
植被刈割对红壤酸度及有机无机复合状况的影响   总被引:10,自引:1,他引:9  
曾希柏  刘更另 《土壤学报》2000,37(2):225-232
在红壤地区自然植被(白茅)条件下,不同的刈割周期对土壤交换性盐基离子组成、土壤有机质、有机无机复合体、腐鱼质组成及铁、铝氧化物含量等均具有较大的影响。从1年刈割一次至6刈割一次处理,虽然土壤酸度的变化无明显规律,但土壤交换性钾、无定形铁、无定形铝、络合态铁的含量及铁活化度值均呈增加趋势,且土壤有机质和复合体的含量相应增高,松结态腐残质/紧结态腐殖质的比值亦增大,即腐残质的活性较强、质量较高,土壤肥  相似文献   

5.
利用具有35a的长期定位试验,在保证原定位试验继续正常开展的前提下,将原化肥处理改施有机肥,原有机肥处理改施化肥或增施有机肥,分析增减施有机肥后耕层土壤团聚体稳定性总有机碳(TOC)及其组分和铁铝氧化物的变化与作用关系,探究胶结物对红壤性水稻土团聚体稳定性变化的影响。结果表明:化肥(CF)及常量有机肥(NOM)处理增施有机肥后,团聚体平均重量直径(MWD)变化不明显,易氧化有机碳(EOC)分别升高87.44%和20.53%;高量有机肥(HOM)及NOM处理减施有机肥后,MWD分别显著降低8.39%和6.80%,高改化(H-C)处理的TOC、轻组有机碳(LFOC)及粗颗粒态有机碳(cPOC)含量显著降低,而常改化(N-C)处理的TOC及其组分变化不明显。无论增施还是减施有机肥,铁铝氧化物含量的变化规律不明显。相关及结构方程模型分析表明,大于0.25mm团聚体含量是影响团聚体稳定性的唯一直接影响因素;影响MWD及大于0.25mm团聚体含量的效应系数由大到小依次为:易氧化有机碳、轻组有机碳、游离氧化铁、络合态铁。因此,大于0.25mm大团聚体在红壤性水稻土的团聚体稳定性中发挥主导作用,有机碳活性组分对大团聚体的形成与破坏具有重要影响。  相似文献   

6.
福建三个垂直带谱中土壤氧化铁的研究   总被引:4,自引:0,他引:4       下载免费PDF全文
应用穆斯堡尔谱分析、化学分析和光学显微镜分析,对福建三条最有代表性的土壤垂直带谱中的粗粒及粘粒氧化铁矿物进行研究。结果表明,赤铁矿从黄壤-黄红壤-红壤-赤红壤逐渐增多而针铁矿逐步减少,粗粒原生矿物组合类型从复杂趋向简单。铁的游离度及晶胶比从黄壤-黄红壤-红壤逐渐升高而活化度逐渐下降,但赤红壤例外,这可能与其成土年龄有关。本文还讨论了土壤分类的有关问题。  相似文献   

7.
不同施肥条件下红壤旱地磷素形态及有效性分析   总被引:14,自引:0,他引:14  
磷素是红壤地区农业生产的最重要的限制因素,因此红壤磷素形态与转化问题的研究,对红壤地区农业生产具有重要意义。用Hedley方法对不同施肥条件下红壤旱地土壤磷素形态进行了研究,结果表明:施磷肥能明显增加红壤各形态无机磷含量和大多数形态有机磷含量;红壤中,对植物最有效的树脂磷和碳酸氢钠磷含量很少,铁铝结合态磷和残留磷含量很多;对有效磷(Bray磷)贡献最大的磷素形态是碳酸氢钠无机磷、铁铝结合态无机磷和存在于土壤团聚体内表面的有机磷。这对于了解不同施肥条件对红壤旱地磷素有效性的影响、探索磷素消长规律、指导红壤旱地磷素管理等都有一定的理论和实践意义。  相似文献   

8.
(一)红壤性水稻土中铁、锰的含量以淀积层最高,潜育层最低。铁、锰在土层中的分化程度,随土壤发育的程度而增加;锰的分化趋势,较铁更为明显。(二)能被氢醌还原的锰量,占全锰中的很大百分数,最高者可达70%,而能被氢醌还原的铁量,不超过全铁量的0.5%。能与EDTA形成络合物的锰量,也较铁量为高。(三)土壤经交互干湿处理以后,酸溶性和易于还原的铁、锰数量都大大降低,说明脱水作用可使铁、锰的活动性减低。(四)作者根据试验结果而认为,锰对氧化还原条件的感应较为灵敏,而铁则对酸碱条件较为敏感,这对于水稻土剖面中铁、锰的移动和分化具有一定意义。铁、锰的移动程度,在一定程度上可作为水稻土发育程度的一个指标。  相似文献   

9.
水稻根际中铁的形态转化   总被引:16,自引:0,他引:16  
王建林  刘芷宇 《土壤学报》1992,29(4):358-364
本文以熟化红壤性水稻土、淀浆白土、红壤和赤红壤为样品,研究了植稻后根际中铁的形态转化.结果表明,两种水稻土根际中无定形氧化铁、游离氧化铁、络合态铁、土壤中氧化铁的活化度及两种红壤上根际中的络合态铁均低于非根际土;而两种红壤上其余各项在根际内外分布趋势均与水稻土相反.用穆斯堡尔谱仪分析表明,所有根际土与非根际土相比,四极矩分裂增大,内磁场下降,说明根际中氧化铁被活化.同时,水稻土上根际中Fe2+增多,赤红壤中根际出现新矿物磁赤铁矿.根际中铁被活化,可能会影响根际中重金属等污染物的吸附和解吸特性、植物的铁素营养及对其它养分的吸收.  相似文献   

10.
福建赤红壤旱地土壤水分特性及调控   总被引:1,自引:0,他引:1       下载免费PDF全文
全斌  陈健飞  郭成达 《土壤》2001,33(5):232-238
福建不同母岩上发育的赤红壤旱地土壤水总库容在熟化度大致相当的情况下相差不大。玄武岩上发育的赤红壤旱地贮水库容、有效水库容分别比花岗岩发育的赤红壤旱地贮水库容、有效水库容要高 ,前者的保水性强于后者。不同利用方式主要通过影响土壤的有机质状况及熟化度 ,进而影响土壤结构 ,导致土壤持水容量不同。赤红壤旱地的比水容量达到 10 2 数量级在 - 10kPa~ 30kPa就开始出现 ,而红壤旱地出现在- 30kPa以下 ,表明赤红壤旱地的失水速度快 ,保水供水性能弱于红壤旱地。为此 ,福建省赤红壤旱地土壤水分调控管理的方向和措施有 :增加降水入渗、调整农业结构 ,采用复合农业技术、增施有机肥和改进灌溉等。  相似文献   

11.
连续九年施用有机肥料,紫色水稻土壤及<0.002mm的有机无机复合体中无定形铁,铝和铬合态铁,铝的含量呈不同程度的增加,铬合态铁和铝间具拮抗作用(r=0.7998n=7);土壤的有机质含量增加主要是由于轻组有机质含量增加,而有机无机复合度下降,土壤重组腐殖质的含量为0.25-0.01mm><0.002mm>1-0.25mm>0.01-0.002mm;有机无机复合度及重组腐殖质中松结态与紧结态的比值  相似文献   

12.
H.H. Le Riche 《Geoderma》1973,9(1):43-57
This previously described buried soil, developed in uniform parent material, was used to study the relative movements of elements and other soil components down the profile. Samples from all horizons were treated with hydrogen peroxide and ammonium oxalate, under ultra-violet light, to remove organic matter and sesquioxides, and the residues were subdivided into six particle size fractions.Downward movement of clay (< 0.5 μm) was accompanied by movement of extractable Al2O3 and Fe2O3, thus identifying these as part of the mobile fraction. The less close relationship of extractable Fe2O3 to the clay suggested that it also occurred partly in coarser aggregates. Proportions of minor elements extracted varied from < 1% for Sr to nearly complete extraction of Co, Cu and Mo in some horizons. The extractable fractions of most minor elements throughout the profile behaved more like Fe2O3 than Al2O3. In the extraction residues, nearly all elements were enriched in the clay fractions relative to the coarser fractions; this being greatest for V and Fe.  相似文献   

13.
Abstract

To evaluate the relationship between the amount of available Silicon (Si) in paddy soils and their mineral properties on the Shounai Plain in Japan, which is formed from several parent materials, we evaluated the amount of available Si, the particle size distribution, the oxide composition of crystalline minerals and the amount of oxalate-extractable Si (Sio), iron (Feo) and aluminum (Alo) in the soil. The amount of available Si in the soil and the oxide content of the crystalline minerals differed among four soil groups that were distinguished by their clay mineral composition. There was no difference in the particle size distribution among the soil groups. The amount of available Si was positively related to the SiO2/Al2O3 ratio of clay, the CaO concentration of silt and fine sand, and the amounts of Sio, Feo and Alo in the soil. The amount of available Si in the soils was negative correlated with the Na2O and K2O concentrations of silt, the K2O concentration of fine sand, and the coarse sand content. These results suggest that the amount of available Si in soils is affected by the weathering resistivity of their minerals and that the particle size distribution and mineral composition are related to the available Si of the soils. Mineralogical properties, including the particle size distribution and mineral composition such as the SiO2/Al2O3 ratio × clay fraction content and the amounts of CaO and MgO in silt-sized particles, were positively correlated with the amount of available Si in the soil, but these correlations were not found for fine sand-sized particles. The Sio, Feo and SiO2/Al2O3 ratio × clay fraction contents contributed approximately 50% to the amount of available Si in the soils. The amount of available Si in the soil was divided into two groups according to the location of the paddy field. The amount of soil-available Si in the alluvial plain was affected by the geology upstream through the mineral composition.  相似文献   

14.
本文应用标准化数据—斜交距离—误差平方和聚类分析法对甘肃成县34个土壤剖面进行了数值分析研究。研究结果表明,供试34个剖面可分为五个土壤类型。对五类土壤的pH值、有机质、代换量、SiO2、Al2O3、Fe2O3、CaCO3及粘粒含量八项主要指标进行方差分析的结果表明,除pH、代换量和SiO2含量未达类型间F测验显著水平外,其他各项指标均达显著或极显著水平。各类土壤在地理分布、植被类型、田间石灰反应等特性上也有明显的差异,并且每一类土壤都具有一定的发生学意义。并分别对应于棕壤、淋溶褐土、褐土、碳酸盐褐土和潮土五种发生学类型。  相似文献   

15.
Based on chemical and mechanical compositions and quartz content of red and/or yellow colored soil materials in the southwestern part of Japan, lithology index (LI) and weathering index (WI) were derived using a multivariate statistical method (factor analysis). The variables used for factor analysis are Fe2O3/Al2O3, TiO2/Al2O3, Fe2O3+Al2O3+Quartz, Si(non-quartz)/(Fe2O3 + Al2O3), CaO + MgO + K2O3, MgO/K2O3 and Quartz/Sand, all of which represent certain different aspects of weathering and/or Iithological characteristics. Since LI and WI are mutually independent, it is possible to evaluate the effect of the degree of weathering on the characteristics of red and/or yellow colored soil materials independently from that of lithology.  相似文献   

16.
Abstract

The capacity of 36 Western Australian soils to adsorb phosphorus (P) was measured by three different methods: P retention index (PRI), P buffering capacity (PBC), and P adsorption (PA). The P adsorption values measured by all three methods varied markedly with soil type. When the P adsorption values were correlated with several soil properties, using simple and multiple linear regressions, PRI, PBC, or PA values were found to be significantly correlated with the aluminium oxide content of the soils. In addition, PBC and PRI was correlated with organic carbon content. The role of aluminium oxide (Al2O3) in the soil was apparently more important in determining the P adsorption capacity of the soils than that of iron (Fe), even though the iron oxide (Fe2O3)content of all the soils studied was consistently higher than the aluminium oxide content. The relationship between P adsorption and the selected soil properties, as determined by multiple linear regression, explained 45–59% of the variation: arabic PRI = ‐10.87 + 9.94 organic C (%) + 160.02 Al2O3 (%), r2 = 0.45.

arabic PBC = ‐0.004 + 1.532 organic C (%) + 22.26 Al2O3 (%), r2 = 0.57.

arabic PA = 3.52 + 248.75 Al2O3 (%), r2 = 0.59.

  相似文献   

17.
试论中国淋溶土的成土过程与基本特性   总被引:2,自引:2,他引:2  
肖笃宁  谢志霄 《土壤学报》1994,31(4):403-412
淋溶土是我国的一类重要土壤,总面积约12.5万km^2。在我国现行的土壤分类系统中,有几个土类-暗棕壤、棕壤、酸性棕壤、白浆土以及部分褐土可归属于淋溶土^1)。这些土壤大都是温带针阔叶混交林下的森林土壤,生物地球化学循环别具特征。据30个剖面的统计分析,其B/A层粘粒含量比值,从暗中壤-棕壤-黄棕壤,为1.47-1.88-2.53,经统计土壤发育过程中粘粒的生成量(或损失量)相差七倍。上述几种土壤  相似文献   

18.
用(NH4)2SO4-浓H2SO4-二胺替吡啉甲烷比色法和NaOH熔融-二胺替吡啉甲烷比色法,分别提取和测定了四川盆地几种主要紫色母岩和土壤中无定型TiO2和全钛。将“全TiO2/无定型TiO2”定义为“钛值”,并用钛值代替硅铝铁率衡量紫色母岩的风化程度。结果为:四川盆地的六种紫色母岩中全钛含量变化于2.95~20.0gkg^-1(TiO2)之间,属中等偏高水平;不同岩性间趋势为泥页岩〉泥岩〉粉砂岩〉砂岩;全量TiO2与岩石的总SiO2含量呈显著的负相关(r=-0.7459^*)。钛值的大小与风化度呈反相关,按钛值的大小,各紫色母岩原始风化度大小顺序如下:三叠纪飞仙关(T1f)〈侏罗纪沙溪庙(J2s)〈侏罗纪自流井(J1-2z)〈侏罗纪蓬莱镇(J3p)〈侏罗纪遂宁组(J3s)〈白垩纪夹关组(K2j)。紫色土壤钛值所反映的风化度与硅铝铁率基本吻合,二者的相关性达到极显著水平(r=0.8615^**)。而土壤胶体的钛值与硅铝铁率的相关系数r=0.8757^**,达极显著相关。土壤钛值所反映的风化度水平与紫色母岩的风化度趋势一致。  相似文献   

19.
Original and published data on the contents of X-ray amorphous oxalate-soluble compounds of Al, Fe, and Si in mesomorphic eluvial soils of cold, moderately cold, and moderately warm continental humid and semihumid regions are generalized. The groups of soils developed from mafic igneous, metamorphic, and pyroclastic rocks are considered. It is shown that the content of oxalate-soluble oxides (OSOx) in the horizons of their maximal accumulation varies from less than 1% to 20–30%; the Alox/Feox ratio varies from 1 to 6.5. The leading factor dictating the amount and quality of the OSOx in the soils is the presence or absence of volcanic glass in the parent materials. The boundary between the soils with and without volcanic glass corresponds to the OSOx content of 5% and the Al2O3ox/Fe2O3ox ratio equal to 2. These criteria are more reliable than the Alox/Feox ratio used by foreign soil scientists to specify Andosols (Alox/Feox > 2). The contents of oxalate-soluble oxides of Al and Fe do not depend on the total contents of these oxides in the parent material and seem to be related to the presence of these elements in minerals with different resistance to weathering. Under the natural conditions described in this paper, the content of OSOx shows a very weak response to zonal (temperature-controlled) climatic changes and/or to changes in the degree of humidity and the continentality of the climate.  相似文献   

20.
Soil irrigation with wastewater (WW) gives the opportunity to solve the problems of its disposal, final purification or reuse. Many studies have examined mineral soils upon continued WW application. The aim of this paper was to examine the properties of organic soils 3 years after WW application was discontinued. Peat‐muck soil planted with Populus spp. or Salix spp., and mineral‐muck soil under grasses were irrigated for 4 years with municipal WW at a low (comparable with intensive NPK fertilization) and high WW rate (600 and 1200 mm yearly, respectively). Soils were analysed for organic matter (OM), pH, bulk density (BD), water holding capacity (WHC), P2O5, Fe2O3, Al2O3, MnO, Zn, Pb, Cu, Cr, magnetic susceptibility (MS) and dehydrogenase and catalase activities. The results were compared with control soils which have never received WW. The study showed that only P2O5, MnO and catalase activity (CA) were significantly affected by former WW application. On average, P2O5 increased by 30 per cent, whereas MnO decreased by 35 per cent with no differences between the two WW rates. CA decreased by 18 per cent at the high WW rate. Most of tested characteristics were determined by soil type. The peat‐muck soil showed higher OM, WHC, P2O5, MnO, Pb and CA than mineral‐muck soil and lower BD, MS, Fe2O3, Al2O3 and Cr. Soil depth influenced Fe2O3, MnO, Zn, MS and enzyme activities, while basic soil properties (OM, pH, BD, WHC and P2O5) were not changed by soil depth. Heavy metals (Zn, Cr, Cu and Pb) were below upper permissible limits. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

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