Cambisols of the Kuznetsk Alatau, their properties and diversity
In the last decade, Cambisols of Eastern Siberia and Transbaikalia, in the Ural region, have been actively studied, whereas the data on Cambisols of the mountains of the south of Western Siberia over the last decade of the XXIth century are insufficient and incomplete. However, the study of cambisols, their properties, genesis, diversity and patterns of spatial distribution is still very important. This research is devoted to the study of the Kuznetsk Alatau Cambisols on the basis of modern diagnostic principles of the substantive-genetic classification of Russian soils and WRB. In this paper, there is a brief overview of the history of studying Cambisols in the Kuznetsk Alatau and the surrounding area. An analogue of Cambisols in the Russian classification is Burozems. The research was conducted in the territory of Kuznetsk Alatau State Nature Reserve (Kemerovo region) within the mountain-forest and high-altitude zones where Cambisols occupy 67% of the area. Fig. 1B shows the spatial distribution of Cambisols in the studied territory. The parent rocks for the studied soils are brown clays and heavy loams of the Quaternary Period of deluvial and deluvial-proluvial origin. According to chemical composition, the parent rocks are non-carbonate and very rarely low carbonate. Field studies were carried out in 2014-2016. For soil diagnostics, we used the Russian Soil Classification (Shishov LL et al., 2004; Field guide of soils in Russia, 2008) and International Soil Classification WRB. For the analytical characteristics of soils, we selected 10 soil profiles (See Table 1), whose samples were analyzed. The main research methods were comparative-geographical, profile-genetic and comparative-analytical. The indicators of the humus state of soils were estimated according to Grishina and Orlov (1978). As a result of the studies, we found out that Burozems (Cambisols) diversity is characterized by two types of soil, nine subtypes, one genus and four species. The types were distinguished by the nature of the surface horizon: Burozem and Burozem raw humic. The subsurface structural-metamorphic (Cambic) horizon and the surface horizon are diagnostic horizons for them: grey humic and raw humic. These types of soils are part of the structural-metamorphic section, which belongs to the post-lithogenic order. Burozem and Burozem raw humic correspond to RSG of WRB: Dystric Cambisols and Folic Cambisols, respectively. The following soil subtypes found in the territory of the Kuznetsk Alatau have been allocated: ordinary, eluvial, clay-illuvial, gleyey and darkprofilic (Eutric Cambisols (Profundihumic). It is dedicated to the soil parent material containing weathering products of carbonaceous slates and limestones. These sediments contain lithogenic organic substance which tinctures the soil profile in gray including the structural-metamorphic (Cambic) horizon. This feature distinguishes them from the brown colored subtypes. The regularities of Cambisols distribution across the studied territory have been revealed. Eutric Cambisols formed everywhere within the mountain-taiga zone under the fir forest on the slopes of different exposition. Folic Cambisols are found mainly in the high-mountain region under the tundra vegetation as well as under the fir and cedar pine open woodland. The influence of the soil parent material manifests itself in Eutric Cambisols (Profundihumic), which are attributed to the sediments containing weathering products of carbonaceous shales and limestones. Cambisols are characterized by acidic reaction in the soil horizons. Folic Cambisols are more acidic soils. They are characterized by higher values of hydrolytic and exchangeable acidity and low base saturation. Eutric Cambisols (Profundihumic) have low acidity and high base saturation because of the influence of parent rock bases. Exchangeable acidity in all studied soils was caused by exchangeable aluminum. Pedogenic accumulation of organic carbon in the upper horizons of the soil profile is typical of Cambisols. Humus type is predominantly fulvate. Also, the humus is characterized by low contents of humic and fulvic acids associated with calcium. Eutric Cambisols (Profundihumic) have a high content of nonhydrolyzable residue in humin, which is caused by the lithogenic properties of the organic matter. The paper contains 3 Figures, 4 Tables and 48 References.