二结构体类型及特性 Granular Block (Sub 确 Platy smatIc Columnar Wedge Examples of Soil Structure
二.结构体类型及特性
二结构体类型及特性 块状 柱状 棱柱状 核状 片状 团粒
二.结构体类型及特性
二结构体类型及特性 (一)块状结构体 cloddy structure Blocky structure 基本特征: (1)近似于立方体 形。其长、宽、高 三轴大体近似等长。 (2)结构体棱角不 明显,呈不规则诨 圆形。 (3)内部较为紧实 北方群众称作“土坷炫”。关中农民称作“胡基”。 SUBANGULAR BLOCKySTRUCTURE 2.类别:按照其大小进行分类 直径>3~5cm叫大央状,<3~5cm叫碎块状结构 3.形成条件和过程:条件:有机物质缺乏、质地粘重(中壤质以上)土壤表层 过程:形成的原因和过程是不合理耕作(过干或过湿耕作)的结果
二.结构体类型及特性 (一)块状结构体: cloddy structure Blocky structure 1.基本特征: (1)近似于立方体 形。其长、宽、高 三轴大体近似等长。 (2)结构体棱角不 明显,呈不规则浑 圆形。 (3)内部较为紧实 北方群众称作“土坷垃”。关中农民称作“胡基”。 2.类别:按照其大小进行分类 直径>3~5cm叫大块状,<3~5cm叫碎块状结构 3.形成条件和过程:条件:有机物质缺乏、质地粘重(中壤质以上)土壤表层。 过程:形成的原因和过程是不合理耕作(过干或过湿耕作)的结果
一)块状结构体: blocky structure blocky structure
(一)块状结构体:blocky structure
二结构体类型及特性 (一)块状结构体: Blocky structure 4.特性 易跑风漏墒(保水性差):大块互相支撑,形成较大空洞,加速了土壤水分的丢失。 难保全苗:块状结构压苗,使幼苗不能顺利岀土。农民常说:麦子不怕草,就怕坷垃咬 直径大于4cm的坷垃危害性非常明显。大于10cm的坷垃危害严重。而2~4cm的坷垃 危害不大,而且有助于防止返盐,发生盐渍化。 5.管理措施: (1)人工机械打碎,费工肥力 (2)在降雨或灌水后适时耙耱,使之破碎平整 (3)利用冻融交替破碎(注意冬灌量) (4)根本方法:增施有机肥,改良质地性状。 Blocky structural peds are found most frequently in the b horizons They have been created by the wetting and drying and freezing and thawing cycle of the b horizon. The clay films also act as a binding agent for the blocky aggregates The b horizon can often be determined in a profile by looking for the location of blocky peds which can be readily seen. Blocky can be either angular(sharp ped edges)or sub-angular (rounded ped edges)
二.结构体类型及特性 (一)块状结构体:Blocky structure 4. 特性: 易跑风漏墒(保水性差):大块互相支撑,形成较大空洞,加速了土壤水分的丢失。 难保全苗:块状结构压苗,使幼苗不能顺利出土。农民常说:麦子不怕草,就怕坷垃咬 直径大于4cm的坷垃危害性非常明显。大于10cm的坷垃危害严重。而2~4cm的坷垃 危害不大,而且有助于防止返盐,发生盐渍化。 5.管理措施: (1)人工机械打碎,费工肥力 (2)在降雨或灌水后适时耙耱,使之破碎平整。 (3)利用冻融交替破碎(注意冬灌量) (4)根本方法:增施有机肥,改良质地性状。 Blocky structural peds are found most frequently in the B horizons. They have been created by the wetting and drying and freezing and thawing cycle of the B horizon. The clay films also act as a binding agent for the blocky aggregates. The B horizon can often be determined in a profile by looking for the location of blocky peds which can be readily seen. Blocky can be either angular (sharp ped edges) or sub-angular (rounded ped edges)