Humus Content in the Lenkoran Lowland Soils | Содержание гумуса в почвах Ленкоранской низменности

The article shows modern studies of the amount of organic matter and humus fractions in gray-brown soils formed in the subtropical climatic zone of the Lankaran region of Azerbaijan — Lankaran, Masalli, Yardimli, Lerik, Jalilabad regions. The reserves, fractions and group composition of humus in alluvial-hydromorphic types and subtypes of soils of the Lankaran lowland were determined. It was early recognized that one of the most important factors in soil analysis was the determination of humus. Sufficient soil moisture and high hydrothermal conditions of marginal dominant soils of region favorably affect the accumulation of a sufficient amount of humus in soils with a large amount phytochemical residues due to the strong development of vegetation. Within the study region, the ecological conditions of humus formation in different landscapes consistently change from more humid to less humid soils. Alluvial gray-brown soils differ sharply from other types in terms of humus and nitrogen reserves. The development of the soil profile varies from 0 to 100 cm in the 123–596 t layer. Gray-brown soils of mesophilic forests are characterized by a low degree of carbonization — 52.1–51.6%, high hydrogen content — 5.59–5.39%. The oxygen content is comparatively less than in brown mountain forest soils. Alluvial-hydromorphic soils with a complete genetic profile are located in flat and weak microlower areas of the Lankaran river basins, formed as a result of the optimal impact of surface and low-mineralized (1.6–2.0 g/l) groundwater (1–1.5 m). Soil organic carbon refers only to the carbon component of organic compounds. Organic carbon is a measurable component of soil organic matter. About 45% of organic matter is carbon and lighter textured soils retain less than 30% of this. Organic matter makes up just 2–10% of most soils mass and has an important role in the physical, chemical and biological function of agricultural soils. The importance of humus as an important element in the process of soil formation and soil fertility was confirmed and substantiated. Orlov and other researchers. Forecasting yields in the long term is an important point in planning agricultural production. It is known that soil humus is the most characteristic and important part of the soil. Carbon stocks are calculated between from 0–100 cm soil depth. According to our study amounts of carbon dioxide in Grey-Brown 4.36, Brown 4.36, Non-Calcareous Brown 6.54, Colluvial 7.55, Alluvial 7.80, Alluvial Coast 8.00, Hydromorphic 12.00 and Chestnut soil 14.90 kg/m2, respectively. Soil organic carbon amounts were higher in Chestnut and in Hydromorphic soils. Chestnut soils have the most organic carbon amount and organic carbon stocks while carbon dioxide was lower in Grey-Brown and Brown. Generally, it is seen that carbon dioxide is low in the area where intense agriculture technique is used, and it is high in forest area which from high area.