The development of the classification of ferrallitic soils in China is reviewed and the classification ofFerralisols and Ferrisols in Chinese Soil Taxonomy is introduced in order to discuss the correlation betweenthe ...The development of the classification of ferrallitic soils in China is reviewed and the classification ofFerralisols and Ferrisols in Chinese Soil Taxonomy is introduced in order to discuss the correlation betweenthe ferrallitic soil classification in the Chinese Soil Taxonomy and those of the other soil classification systems.In the former soil classification systems of China, the ferrallitic soils were classified into the soil groups ofLatosols, Latosolic red soils, Red soils, Yellow soils and Dry red soils, according to the combination of soilforming conditions, soil-forming processes, soil features and soil properties. In the Chinese Soil Taxonomy,most of ferrallitic soils are classified into the soil orders of Ferralisols and Ferrisols based on the diagnostichorizons and/or diagnostic characteristics with quantitatively defined properties. Ferralisols are the soilsthat have ferralic horizon, and they are merely subdivided into one suborder and two soil groups. Ferrisolsare the soils that have LAC-ferric horizon but do not have ferralic horizon, and they are subdivided intothree suborders and eleven soil groups. Ferralisols may correspond to part of Latosols and Latosolic red soils.Ferrisols may either correspond to part of Red soils, Yellow soils and Dry red soils, or correspond to part ofLatosols and Latosolic red soils.展开更多
Water stored in deep loess soil is one of the most important resources regulating vegetation growth in the semi-arid area of the Loess Plateau, but planted shrub and forest often disrupt the natural water cycle and in...Water stored in deep loess soil is one of the most important resources regulating vegetation growth in the semi-arid area of the Loess Plateau, but planted shrub and forest often disrupt the natural water cycle and in turn influence plant growth. The purpose of this study was to examine the effects of main vegetation types on soil moisture and its inter-annual change. Soil moisture in 0-10 m depth of six vegetation types, i.e., crop, grass, planted shrub of caragana, planted forests of arborvitae, pine and the mixture of pine and arborvitae were measured in 2001,2005 and 2006. Soil moisture in about 0-3 m of cropland and about 0-2 m of other vegetation types varied inter-annually dependent on annual precipitation, but was stable inter-annually below these depths. In 0-2 m, soil moisture of cropland was significantly greater than those of all other vegetation types, and there were no si nificant differences among other vegetation types. In 2-10 m, there was no significant mois- ture difference between cropland and grassland, but the soil moistures under both of them were significantly higher than those of planted shrub and forests. The planted shrub and forests had depleted soil moisture below 2 m to or near permanent wilting point, and there were no significant moisture differences among forest types. The soil moisture of caragana shrub was significantly lower than those of forests, but the absolute difference was very small. The results of this study implicated that the planted shrub and forests had depleted deep soil moisture to the lowest limits to which they could extract and they lived mainly on present year precipitation for transpiration.展开更多
文摘The development of the classification of ferrallitic soils in China is reviewed and the classification ofFerralisols and Ferrisols in Chinese Soil Taxonomy is introduced in order to discuss the correlation betweenthe ferrallitic soil classification in the Chinese Soil Taxonomy and those of the other soil classification systems.In the former soil classification systems of China, the ferrallitic soils were classified into the soil groups ofLatosols, Latosolic red soils, Red soils, Yellow soils and Dry red soils, according to the combination of soilforming conditions, soil-forming processes, soil features and soil properties. In the Chinese Soil Taxonomy,most of ferrallitic soils are classified into the soil orders of Ferralisols and Ferrisols based on the diagnostichorizons and/or diagnostic characteristics with quantitatively defined properties. Ferralisols are the soilsthat have ferralic horizon, and they are merely subdivided into one suborder and two soil groups. Ferrisolsare the soils that have LAC-ferric horizon but do not have ferralic horizon, and they are subdivided intothree suborders and eleven soil groups. Ferralisols may correspond to part of Latosols and Latosolic red soils.Ferrisols may either correspond to part of Red soils, Yellow soils and Dry red soils, or correspond to part ofLatosols and Latosolic red soils.
基金National Key Basic Research Special Foundation Project of China, No.2007CB407204National Natural Science Foundation of China, No.40471082
文摘Water stored in deep loess soil is one of the most important resources regulating vegetation growth in the semi-arid area of the Loess Plateau, but planted shrub and forest often disrupt the natural water cycle and in turn influence plant growth. The purpose of this study was to examine the effects of main vegetation types on soil moisture and its inter-annual change. Soil moisture in 0-10 m depth of six vegetation types, i.e., crop, grass, planted shrub of caragana, planted forests of arborvitae, pine and the mixture of pine and arborvitae were measured in 2001,2005 and 2006. Soil moisture in about 0-3 m of cropland and about 0-2 m of other vegetation types varied inter-annually dependent on annual precipitation, but was stable inter-annually below these depths. In 0-2 m, soil moisture of cropland was significantly greater than those of all other vegetation types, and there were no si nificant differences among other vegetation types. In 2-10 m, there was no significant mois- ture difference between cropland and grassland, but the soil moistures under both of them were significantly higher than those of planted shrub and forests. The planted shrub and forests had depleted soil moisture below 2 m to or near permanent wilting point, and there were no significant moisture differences among forest types. The soil moisture of caragana shrub was significantly lower than those of forests, but the absolute difference was very small. The results of this study implicated that the planted shrub and forests had depleted deep soil moisture to the lowest limits to which they could extract and they lived mainly on present year precipitation for transpiration.
