南京紫金山林地与耕地土壤腐殖质组成的研究

土壤腐殖质组成对土壤形成过程及土壤性质、土壤肥力的重要作用,已为前人所肯定^[2,3,7]。土壤腐殖质组成决定于植被、土壤微生物的活动、土壤性质和土壤水热条件,不同土类之间由于以上几方面因子的不同,腐殖质组成亦不相同,各类土壤都有其特点,这方面的工作,已为丘林及科諾諾娃等总结过了^[7,2],至于在同一类土壤上植被或耕作利用等的不同对腐殖质组成的影响,则研究尚少,而这方面的研究将有助于认识土壤肥力的演变规律,对于拟定控制和提高土壤肥力的措施方面,提供必要的资料。     

昆明地区不同母质对红壤发育的影响

昆明地区位于云南省中部,为我国西南高原红壤的主要分布区。关于本区土壤形成过程及发生分类等同题,虽然曾有人做过不少工作,但至今仍存在着一些分歧;有人认为本区土壤的形成过程以砖红壤化为主,土壤类型为砖红壤及铁质砖红壤性土^[1,2];有人认为棕壤化为本区土壤的主要成土过程,土壤应命名为棕色森林土^[4];另有人认为本区土壤属红壤,目前的成土过程为红壤化^[5],所有这些意见,均因资料不足而难取得统一。     

不同熟化度红壤及红壤性水稻土的腐殖质组成及其特性

土壤腐殖质是评价红壤肥力的重要因素^[2],根据前人研究^[8,3,1]:一般土壤腐殖质的含量及组成受土壤地带性的影响。胡敏酸与富啡酸的比值自南向北逐渐递增,红壤胡敏酸与富啡酸的比值小于1。本文着重研究同一地区自然成土因素类同的情况下,红壤通过水旱耕作和培肥,土壤腐殖质的组成及特性的变化。     

天津地区土壤中若干金属元素间的相关性

土壤中的元素主要来源于成土母质^[1],但在风化成土过程中,元素的迁移与富集能力各不相同。为了寻求土壤中元素间的内在联系,判断元素的含量和分布状况,元素间的相关分析法是良好的方法之一。例如,Ure等^[6]测定了苏格兰不同母质的土壤中多种微量元素含量,并讨论了各元素间的相互关系。Pilotte等^[5]用相关性分析法对河口地区沉积物中元素含量进行判断,浅见辉男等^[4]用元素相关性描述了沉积物中元素分布,梁伟^[5]用元素相关性对土壤背景值进行判断等。本文根据天津地区土壤表土中16个元素之间的相关系数,探讨元素的地球化学性质对元素间的相关性的影响。     

华北平原瓦碱的特性和形成

华北平原广泛分布着一种具有灰白色紧实结壳的土壤,群众称为瓦碱(或岗瓦碱)。这种土壤在冀^[1]、鲁^[2]、豫^[3]、苏^[4,5]、皖^[6,7,8]五省都有分布,一般认为这是一种碱化土壤,但其性质及形成过程还不够清楚。根据国内外的研究资料,碱化土壤多分布于栗钙土、黑土及棕色荒漠草原土带,至于褐土带地区浅色草甸土发生碱化过程,在土壤学研究中还是一个新问题。因此,我们曾对山东、河南某些瓦碱进行了一些工作,今将初步结果报导如下。     

中国土壤胶体研究Ⅲ.褐土胶体的矿物组成

褐土广布我国华北地区,常与棕色森林土和浅色草甸土相伴发生^[1,5]。关于华北地区褐土的发生类型、形成环境、分布规律以及演变过程的研究,已有详细报告^[2],本文拟就粘土矿物组成方面阐明褐土的性质,特选出几个土壤剖面,分离其胶体(小于1微米)部分,进行矿物组成的研究。     

中国土壤颗粒研究——Ⅰ.太湖地区白土型水稻土中白土层土壤及其各级颗粒的理化特性

研究土壤各级颗粒的理化特性,是土壤基本性质研究的重要内容之一。有关土壤及其粘粒化学组成的研究报导,在国内外并不鲜见,但对土壤各级颗粒性质的研究则较少。关于土壤各级颗粒的矿物全量分析研究,熊毅^[12]、于天仁^[1]早已有报导。国外的研究也大多在早地上进行^[16,18-23]。至于对水稻土的各级颗粒的理化特性研究,在国内尚未见有报导。因此,开展这方面的研究是很有意义的,不仅有助于深入探究土壤高产或低产的原因,而且可以加深对土坡颗粒基本性质的认识,为完善我国土壤质地分类提供科学依据。     

红松天然林不同林型下土壤微生物学特性的研究

林木的生长发育与环境条件,其中包括土壤条件,有着紧密的相互联系。发育在天然林下或人工林下的土壤的性质,不仅反映了森林对土壤发生、发展和肥力形成过程的影响,而且也反映了土壤对森林群落结构的组成和演变,以及林木生产力的影响^[1]。在天然林下,林木雕落物是恢复森林土壤肥力的主要物质来源。不同森林群落结构下,由于林分的组成不同,雕落物的成分也不一样。     

土壤中氧化铁的转化及其对土壤结构的影响

氧化铁虽是土壤粘粒中的次要矿质成分,但它具有较高的活性,对土壤性质有重要的影响。作为胶结物质之一,氧化铁的形态及其含量,对土壤团聚体的形成,亦起重要作用^[4,8]。某些水稻土中细孔隙增多,土块趋向紧实等问题^[1,2],似乎与土壤中氧化铁存在形态有关。     

磷肥在土壤中的转化及其与土壤有效磷的关系

自从张守敬和Jeckson(1957年)提出土壤无机磷分级方法以来,国内外许多土壤农业化学家对土壤有效磷与各级无机磷之间的关系^[1],作物吸磷状况与土壤无机磷组成的相关性^[2],水稻生长期间土壤有效磷增加的机理^[3],以及磷肥对土壤无机磷组成的影响和转化等方面作了广泛的研究^[4]。     

Characteristics of Humic Substances in Paddy Soils

In the present paper,the composition of humus and the charateristics of humic acid from seven paddy soils were compared with those of upland (and/or natural) soils.Results show that:(1) in each group of the soil samples for comparison the HA/FA ratio of the humus of a paddy soil,in most cases,was appreciable higher than that of adjacent upland(and/or natural) soil derived from the same parent material;(2) the humic acid extracted from the paddy soils was characterized by a higher C/O ratio,a higher content of methoxyl groups,and a lower content of carboxyl groups than those from the corresponding upland (and/or natural) flooded soils,implying that the humic acid formed under rice cultivation is in a lower degree of humification than that formed under upland(and/or natural) conditions;and (3) the humic acid of paddy soils,however,was not always characterized by a lower aromaticity than that of the corresponding upland(and/or natural) soils.     

我国几种土壤中腐殖质性质的研究

研究了几种土壤腐殖酸的基本性质,其中包括土壤的腐殖质组成,胡敏酸以及富里酸的元素组成,含氧官能团含量,光密度值与芳化度等,计算了E₄与E₄/E₆比值与上述性质的相关系数。结果表明土壤腐殖质组成和性质与其形成条件有着密切的联系,并且有一定的地带规律性。水稻土中有机质含量增加,HA/FA比值变高,其活性HA显著降低,说明水稻土有利于有机质的积累并改变了腐殖质的组成。E₄、E₄/E₆比值与元素组成,C/H比值,含氧官能团及芳化度之间的相关系数表明E₄除了与C%,O%,酚羟基-O%,醌基-O%呈极显著或显著相关外,还与C/H比值及芳化度呈极显著相关,因此E₄值可作为腐殖物质芳化度的一个指标。     

Characters of humus formed under rice cultivation

To characterize the nature of humus in paddy soils, a comparison was made between the properties of humus in paddy soils and those in adjacent unflooded arable soils.

Rice cultivation generally brought about a considerable increase in organic matter and in the PQ-value, with the exception of Andosol-paddy soils in which organic matter tended to decrease somewhat and the PQ-value remained virtually unchanged. The humification degree of humic acid as judged from Δ log k and RF values was generally lowered by rice cultivation except in the case of Yellow soil-paddy soil in which humic acid was originally low in the degree of humification.

The accumulation of poorly humified humic acid may be a characteristic feature common to all paddy soils. These changes by rice cultivation are observed only in the upper part of the profiles, and seem to be associated with seasonally flooded conditions ot paddy soils. Iron oxides accumulated in subsurface soil have virtually no effect on the properties of humus.     

Combination reaction between humic acid and calcium ions

In the previous paper (1), liming an acid humus volcanic ash soil resulted in the formation of humic acids combined with calcium, but had no significant effect on acid brown forest soils containing humic acids of a lower degree of humification. Subsequently, the authors examined the humus composition of the soils treated with calcium acetate, and conducted some experiments on the combination reaction between humic acid and calcium ions. The results obtained are presented in this paper.     

The humus status of brown forest soils and its changes upon intensive tea growing in the subtropical zone of Russia

Changes in the humus status of acid brown forest soils used for tea growing have been studied in a long-term stationary experiment after 20 years of the application of mineral fertilizers in increasing doses. It is shown that long-term tea growing has resulted in a reliable increase in the humus content within the upper cultivated horizon (Ap, 0–40 cm) at the expense of the nonhydrolyzable fraction of humus (humin) and the first fractions of humic and fulvic acids. The fractional composition of humus has changed against the background of a stable fulvate type of humus (Cha/Cfa < 0.5). The portion of the first fraction of humic and fulvic acids in the total amount of humus has increased, as well as the portion of the first fraction of humic acids in the total amount of humic acids. These changes are due to the enhanced humification of plant residues with a parallel decrease in the contents of the second (Ca-bound) and third (bound with clay and stable sesquioxides) fractions of humic substances.     

大兴安岭北部的灰化土

大兴安岭北部,即伊勒呼里山以北的大兴安岭主体部分,大致位于北纬51°20'—53°28',东经121°31'—126°30'之间,是我国的最北端。其地带性土壤类型,过去说法不一,曾有人命名为生草灰化土¹⁾、棕色灰化土、棕色泰加林土²⁾、灰白色森林土(中国科学院内蒙古宁夏综合考察队等,1978)、棕色针叶林土³⁾、漂灰土(中国科学院南京土壤研究所主编,1978)等。     

江西低丘红壤性水稻土的主要化学特性研究

三个红壤性水稻土的有机质和腐殖质的含量由淹育型水稻土→潴育型水稻土→潜育型水稻土依次逐渐增加,其C/N和H/P比值也顺次增大。它们的粘土矿物组成无明显差异。铁、锰物质在潴育型水稻土剖面中分异最明显,其次为淹育型水稻土;而无定形氧化铁在剖面中变幅最大却是潜育型水稻土;结晶态铁在土壤剖面中分异亦有一定规律,其中潴育型水稻土的指示性土层(W层)的晶胶率(结晶铁/无定形铁)远较其它土层为高,这种变化特性的差异,对区分不同水分作用的水稻土发育类型有一定的特殊意义;土壤络合态铁与土壤有机质含量有关。土壤氧化锰与土壤氧化铁相比虽然含量低,但对土壤氧化还原条件反应更加敏感,所以在土壤剖面中淋移趋势更加明显。     

滨海水稻土腐殖质的组成及随种稻时间演变的研究初报

通过研究滨海水稻土腐殖质各成分的组成及性质,结果表明各组分有机碳及氮含量均为表层最高,C/N在结构相对稳定的结合态腐殖质和胡敏酸(HA)中波动较小,而在游离态腐殖质和富里酸(FA)中变化较大。随着种稻时间变长,结合态的腐殖质和胡敏酸有在土壤中积累的趋势,在1 000 a水稻土中腐殖质的芳香化程度最高、结构最复杂。     

Humus composition of soils under forest, coffee and arable cultivation in hilly areas of south Sumatra, Indonesia

To understand the effect of land use changes on the composition of humus in tropical soils, samples from land under primary forest, secondary forest, coffee plantation, and arable crops were investigated at three sites in south Sumatra, Indonesia. Total carbon and total nitrogen contents were 1.7 to 4.3 times and 1.1 to 2.8 times greater in the topsoil under primary forest than under the other types of land use. Following change from primary forest to other uses, the proportion of humic acids in the organic matter of the topsoils decreased while that of the fulvic acid fraction increased. Within the range of land uses, differences in the yields of humic acids and fulvic acid fractions were, respectively, larger and smaller than those in total carbon content. The humic acids were classified into the low and middle classes in the degree of humification. Absorption due to the green fraction of humic acids, Pg, was detected in the UV‐visible spectra of almost all the humic acids. No relation was observed between the degree of humification of humic acids or the strength of Pg absorption in their spectra and land use change. The fulvic acid fractions were fractionated on insoluble polyvinylpyrrolidone (PVP) into the adsorbed fractions consisting of humic substances and the non‐adsorbed fractions consisting of non‐humic substances. A positive correlation between the amount of the fulvic acid fraction and the percentage of the PVP‐adsorbed fraction within it indicated that the variation in the amount of the fulvic acid fraction was attributable to acid‐soluble humic substances. The ionization difference spectra of solutions between pH 12 and pH 7 suggested that the chemical structures of the PVP‐adsorbed fulvic acids have been altered by land use change.