Does tree species composition control the soil carbon stocks of the Hyrcanian forest in the Northern Iran? (A case study in Guilan province, Iran)

Abstract

This work studied the effects of tree species composition on soil carbon storage in five mixed stands dominated by oriental beech and grown in the western Caspian region in Guilan province, called Astara, Asalem, Fuman, Chere and Shenrud. The thickness of the litter layer, soil characteristics, tree composition and percentage of canopy coverage were measured in each stand. Total soil organic carbon differed significantly by stand. Total (organic) carbon stores at Fuman, which had the lowest tree species richness with 2 species and least canopy coverage (75%), were significantly (p <0.05) higher than at other locations. Carbon storage in topsoil (0–10 cm) was significantly lower in Shenrud, which had the highest tree species richness with 5 species and highest canopy coverage (95%). The high percentage of canopy coverage in Shenrud probably limited the conversion of litter to humus. However, in the second soil layer (10–25 cm), Asalem, with high tree species richness and canopy coverage, had the highest carbon storage. This can be explained by the different rooting patterns of different tree species. In the Hyrcanian forest. According to the results, it can be concluded that not only tree composition but also canopy coverage percentage should be taken under consideration to manage soil carbon retention and release.

Keywords

beech forest / canopy coverage / soil carbon stocks / tree composition

References

[1] Adger WN, Brown K, Shiel RS, Whitby MC. Carbon dynamics of land use in Great Britain. J. Environ. Manage, 1992, 36(2): 117-133.

[2] Berger T, Hager H. Physical top soil properties in pure stands of Norway spruce (Picea abies) and mixed species stands in Austria. Forest Ecol Manage, 2000, 136(1–3): 159-172.

[3] Berger T, Neubauer C, Glatzel G. Factors controlling soil carbon and nitrogen stores in pure stands of Norway spruce (Picea abies) and mixed species stands in Austria. Forest Ecol Manage, 2002, 159(1–2): 3-14.

[4] Blake GR, Hartge KH. Klute A. Bulk density. Methods of soil analysis, 1986 2nd ed. Madison (WI): Agronomy Society of America and Soil Science Society of America, 363 75

[5] Brown S, Lugo AE. Effects of forest clearing and succession on the carbon and nitrogen content of soils in Puerto Rico and US Virgin islands. Plant Soil, 1990, 124(1): 53-64.

[6] Gee GW, Bauder JW. Klute A. Particle-size analysis. Methods of soil analysis, 1986 2nd ed. Madison (WI): Agronomy Society of America and Soil Science Society of America, 383 411

[7] Gower ST. Patterns and mechanisms of the forest carbon cycle. Ann Rev Environ Resour, 2003, 28(1): 169-204.

[8] Guo LB, Gifford RM. Soil carbon stocks and land use change: A meta analysis. Global Change Biol, 2002, 8(4): 345-360.

[9] Jennings SB, Brown ND, Sheil D. Assessing forest canopies and understory illumination: canopy closure, canopy cover and other measures. Forestry, 1999, 72(1): 59-74.

[10] Johnson DW, Curtis PS. Effects of forest management on soil C and N storage: meta analysis. Forest Ecol Manage, 2001, 140(2–3): 227-238.

[11] Johnson DW. Effects of forest management on soil carbon storage. Water Air Soil Poll, 1992, 64(1–2): 83-120.

[12] Kim CS, Son Y, Lee WK, Jeong JY, Noh NJ. Influences of forest tending works on carbon distribution and cycling in a Pinus densiflora S. stand in Korea. Forest Ecol Manage, 2009, 257(5): 1420-1426.

[13] Korhonen L, Korhonen KT, Rautiainen M, Stenberg P. Estimation of forest canopy cover: a comparison of field measurement techniques. Silva Fennica, 2006, 40(4): 577-588.

[14] Marimon-Junior BH, Hay JD. A new instrument for measurement and collection of quantitative samples of the litter layer in forests. Forest Ecol Manage, 2008, 255(7): 2244-2250.

[15] McLean EO. Methods of Soil Analysis. 1982, Madison (WI): Agronomy Society of America and Soil Science Society of America, 199 224

[16] McPherson GR, Boutton TW, Midwood AJ. Stable carbon isotope analysis of soil organic matter illustrates vegetation change at the grassland/woodland boundary in southeastern Arizona, USA. Oecologia, 1993, 93(1): 95-101.

[17] Nelson DW, Sommer LE. 1982. Methods of Soil Analysis. Madison (WI): Agronomy Society of America and Soil Science Society of America, pp. 539-77.

[18] Sagheb-Talebi K, Schütz JPh. The structure of natural oriental beech (Fagus orientalis) forests in the Caspian region of Iran and the potential for the application of the group selection system. Forestry, 2002, 75(4): 465-472.

[19] Son Y, Park IH, Yi MJ, Jin HO, Kim DY, Kim RH, Hwang JO. Biomass, production and nutrient distribution of a natural oak forest in central Korea. Ecol Res, 2004, 19(1): 21-28.