Assessment of Carbon Stocks in Soils Forests of the South of Primorye

The main reserves of organic matter of terrestrial ecosystems of the planet are accumulated in forest soils. The patterns of changes in carbon stocks depending on the location in the relief and vegetation in Haplic Cambisols (brown soils typical) of broad-leaved forests of the western spurs of the Sikhote-Alin Primorsky Territory are studied. Haplic Cambisols of the south-southeastern and north-northwestern slopes morphologically differ in the thickness of the genetic horizons and the degree of stony. Their carbon reserves vary depending on the location and the prevailing tree species, and they gradually increase in soils from the watershed downhill to the foot. The largest carbon reserves were found in the soils of the floodplain of the stream in the area of birchash mixed forest (104–108 t/ha in layers 0–30 and 0–50 cm), the smallest – in the soils of the steep slope of the southern exposure under xerophytic oak forests (65–67 t/ha, in layers 0–30 and 0–50 cm). The data obtained fully correspond to the assessment of carbon reserves in soil layers for the Primorsko-Priamursky coniferous-deciduous region of the Far East. Close relationships have been revealed between the content of exchangeable bases, organic carbon, available forms of nutrients (phosphorus and potassium), actual acidity and the content of the fraction of physical clay.