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本研究基于黄淮海平原多个变性土剖面分层土壤样品的土壤理化性状分析数据,对其肥力特征、生产性能以及培肥改良措施进行了系统研究。相关结果表明,机械组成中粘粒含量高、质地粘重、土壤结构和孔隙性差是变性土主要物理性状特征,受其影响,土壤表现出耕作性能差、蓄水能力弱、保水性能不强等特点;化学性状主要表现为有机质含量不高、质量差,土壤氮素水平仍较低,耕层土壤速效磷含量分异加大,土壤速效钾含量缓慢降低,土壤CEC含量较高,土壤保肥性能强,但供肥性能较差等特点。这些性状特点对土壤生产性能的影响主要表现在土壤适耕期短,易受旱、涝(渍)灾害的危害,土壤有效养分低、营养失调,钙质结核影响土壤蓄水能力和水分运行以及作物根系生长等方面。指出:(1)增加土壤有机质,改良土壤理化性质;(2)合理施肥,促进土壤养分平衡;(3)改进耕作、灌溉技术,调控土壤水分状况等是培育变性土肥力质量、提高土壤生产性能的关键性措施。 相似文献
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有关中国上古时代(唐、虞、夏、商、周五朝代)农业生产的土壤鉴别和土地利用法则的探讨 总被引:1,自引:0,他引:1
导言回忆1935年参加在牛津召开的第三次国际土壤学大会时,我曾著文论述广东省土壤调查工作的经始和成就。在引言中介绍我国古代夏禹治平水土后,曾辨别九州的土壤,并比较其肥力而制定赋贡之法。但语焉不详,久思有机会再为整理这项古籍资料以贡献。解放后,因在华北工作,时有机会与农民羣众接触,学习颧摩,认识多少传统的 相似文献
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山西省土地利用率高。凡有黄土分布的丘陵地区,就有人为耕作活动影响;高中山地区森林植被破坏严重,草地退化;少数平川地全是农业基地。因此,生态系统恶化,灾害频繁,水土流失严重。全省每年平均向黄河、海河输送泥沙4.56亿吨。国土是民生之本,是经济起飞的基础。保护好土地资源,进行科学的综合开发利用,是全省的当务之急。 相似文献
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C. N. MACVICAR 《European Journal of Soil Science》1969,20(1):141-152
Considering the nature of soil and the ends which a classification must serve, principles are stated whereby a soil classification may be devised for application over extensive areas of varied soil composition. Naturally occurring bodies of soil, each with a high degree of homogeneity, are apparent rather than real individuals as their properties overlap to form a continuum. This continuum is multi-dimensional because soil is characterized by numerous properties. The procedure of devising a classification is one of subdividing the continuum such that class boundaries accommodate, as far as possible, apparent individuals rather than of grouping like apparent individuals together. A classification may be used to locate the position of a profile in the continuum and so define its relationship with other profiles. It may also be used to indicate the soil composition of land by using soil classes on a map to show differences in the soil mantle. The latter procedure may best be regarded as land classification or soil mapping rather than soil classification; a class of land or mapped area seldom contains profiles belonging exclusively to a single class, whereas a soil class never contains profiles of another class. The soil form, a specific arrangement of diagnostic horizons, is introduced as a category above the series to facilitate the identification of soil profiles. Member series of a form are defined according to property variations within the diagnostic horizons of the form. It is suggested that a binomial system of profile nomenclature, using the form and the series, would have much to commend it. 相似文献
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SOIL CLASSIFICATION IN THE SOIL SURVEY OF ENGLAND AND WALES 总被引:2,自引:0,他引:2
B. W. AVERY 《European Journal of Soil Science》1973,24(3):324-338
The development of soil classification as a basis for soil mapping in England and Wales is briefly reviewed, and a system for future use is described. The things classified are soil profiles, and classes are defined by relatively permanent characteristics that can be observed or measured in the field, or inferred within limits from field examination by comparison with analysed samples. Profile classes are defined at four categorical levels by progressive division, and are termed major groups, groups, subgroups, and soil series respectively. Classes in the three higher categories are defined partly by the composition of the soil material and partly by the presence or absence of particular diagnostic horizons, or evidence of recent alluvial origin, within specified depths. Soil series are distinguished by other characteristics, chiefly lithologic, not differentiating in higher categories. Most of the soil groups, regarded as the principal category above the soil series, are closely paralleled in other European systems, in the U.S.D.A. system (7th Approximation with subsequent amendments), or in both. Compared with the system used hitherto, the main innovations are the use of specific soil properties to define classes at all categorical levels, and the separation at group level of classes based primarily on inherited lithologic characteristics. The soil-profile classification provides a uniform basis for identifying soil map units, considered as classes of delineated soil bodies. When a map unit is identified by the name of a profile class, it is implied that most of the soil in each delineation conforms to that class, and that unconforming inclusions belong to one or more closely related classes or occupy an insignificant proportionate area. Map units identified by land attributes not differentiating in the profile classification are termed phases. 相似文献
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中国土壤分类四十年 总被引:5,自引:0,他引:5
建国以来土壤分类是不断完善的过程。涉及全国的土壤分类系统至少有9个。可分为三个时期。解放初,采用美国马伯特土壤分类系统,以土类为基本单元,土系为基层单元,其中就有我国特有的山东棕壤、砂姜黑土和水稻土等类型;从1954年开始采用土壤发生分类系统,之后陆续提出了一些新土类,如黄棕壤、黑土、白浆土、砖红壤性红壤等,接着由于对耕地土壤的普查,充实了水稻土、明确了潮土、灌淤土和塍土等的独立土类地位。并提出了其他许多磷质石灰土等新土类。目前正在开始以诊断层如诊断特性为基础、结合我国丰富土壤类型的实际,在已有基础上,建立具有我国特色、具有空量指标的土壤系统分类。但这需要有一个较长的研究和完善过程。 相似文献
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本文主要阐述国外近年来,在干旱半干旱地区土地开发概况,初步整理了各国开发治理的措施与途径,并指出这类地区,仍存在着严重的生态威胁。土地开发整治工程,就是从保护观点出发,开发利用这一自然特定地域,建设农业基地,控制生态恶化。文中还指出,随着世界农业发展进程,如何合理、有效、适度地进行干旱半干旱地区土地开发和建设,仍是当今急待解决的世界性课题。我国西北干旱地区的开发整治,正面临这一挑战。 相似文献