淋溶土 （英語： Alfisol），又名 淋育土 、 聚铝铁土，是 美国农业部土壤分类系统 划分土纲之一。 淋溶土在湿润到半干旱半湿润的地方形成，尤其是在 硬木 森林的覆盖下。 淋溶土的 底土 中富含黏土，相对较高的天然肥力。 英文名中的前缀“Alf”指铝（Al）和铁（Fe），中文的“淋溶”则指 淋溶作用。 淋溶土肥沃而且常见，是农业生产的最重要的土纲之一。 在农林业广泛使用，比其他湿润气候土壤更容易保持肥沃，尽管 澳大利亚 和 非洲 的淋溶土十分缺 氮 和 磷。 热带 季风 区 …

Alfisols are a soil order in USDA soil taxonomy. Alfisols form in semi-arid to humid areas, typically under a hardwood forest cover. They have a clay-enriched subsoil and relatively high native fertility. "Alf" refers to aluminium (Al) and iron (Fe).

The central concept of Alfisols is that of soils that have an argillic, a kandic, or a natric horizon and a base saturation of 35% or greater. They typically have an ochric epipedon, but may have an umbric epipedon. They may also have a petrocalcic horizon, a fragipan or a duripan.

淋溶土（Alfisols, leached soil）隶属在土壤分类架构当中的一个重要土纲，此类土壤与极育土性质类似，淋溶土是指湿润土壤水分状况下，石灰充分淋溶，具有明显黏粒淋溶和淀积的土壤。

Alfisols are arable soils with water content adequate for at least three consecutive months of the growing season. Prior to cultivation they are covered with natural broad-leaved deciduous forest vegetation, sometimes interspersed with needle-leaved evergreen forest or with grass.

Alfisols are moderately leached soils that have relatively high native fertility. These soils have mainly formed under forest and have a subsurface horizon in which clays have accumulated. Alfisols are primarily found in temperate humid and subhumid regions of the world.

Alfisols are forest soils that have relatively high native fertility. These soils are well developed and contain a subsurface horizon in which clays have accumulated. Alfisols are mostly found in temperate humid and subhumid regions of the world.

Alfisols are very good agricultural soils, developing from loamy till and containing the organic matter and clay that serve to retain moisture and enhance fertility. You might find these chapters and articles relevant to this topic. Most Alfisols were or are forested, with moderate to high base saturation; most formed under deciduous forest.

Alfisol soil can be found in deciduous forests. They have a brown to gray-brown A-horizon. Precipitation is great enough to wash away most of the clay and soluble nutrients out of the A and E horizons and into the B horizons.

Alfisols are forest soils that have relatively high native fertility. Alfisols typically exhibit well-developed, contrasting soil horizons (layers) depleted in calcium carbonate but enriched in aluminum- and iron-bearing minerals. Below the surface horizon lies a region with significant accumulation of translocated (migrated) layer silicate clay.