Fertility and sequestered organic carbon status in the soils under different forest stands in garhwal himalayas, india

Abstract

A study was conducted to estimate the fertility status of soil and sequestered organic carbon under different forest covers viz. Shorea robusta, Pinus roxburghii, Quercus leucotrichophora, Cedrus deodara, Picea smithiana and Abies pindrow and Miscellaneous forests, available in Gharwal region of Uttarakhand. Soils were well enriched by primary nutrients i.e. available nitrogen, phosphorus and potassium. Available nitrogen was higher under P. smithiana & A. pindrow followed by C. deodara and the least was under miscellaneous forests. In general, nutrients were decreasing with increasing soil depth under all the forest stands. Soil reaction was mild acidic in all the depths under all forest stands. Ex. Ca, Mg, K and Na were higher in surface layer and decreased with increasing the depth. Soil texture under C deodara was loam, under P. roxburghii and miscellaneous was sandy clay loam while in other it was clay loam to sandy loam within the profile up to 120 cm depth. SOC stock was maximum P. smithiana and A. pindrow (138.01 t ha -1 ) followed by C. deodara (122.63 t ha -1 ), Q. leucotrichophora (109.37 t ha -1 ), P. roxburghii (66.04 t ha -1 ), S. robusta (65.26 t ha -1 ) and the least was in the soils under miscellaneous forests (65.02 t ha -1 ). Forests like P. smithiana & A. pindrow, Q. leucotrichophora and C. deodara, growing at higher altitudes have higher potential to sequester more organic carbon in the soils as compared to the forest like S. robusta, P. roxburghii and miscellaneous growing at lower altitude. Results of one - way ANOVA indicates that SOC pool between the natural forests was significantly different at 0.05 level (Variance ratio, F = 65.62; p < 0.05). Vegetation parameter indicates that maximum dbh, basal area and crown area was recorded in S. robusta followed by P. smithiana & A. Pindrow and the least was in miscellaneous. However maximum height was recorded in C. deodara followed by P. smithiana & A. pindrow, P. roxburghii and the least was in Q. Leucotrichophora.