SOIL CARBON CONTENT AND MICROBIAL BIOMASS ACTIVITY OF DIFFERENT FOREST TYPES UNDER SEASONAL VARIATIONS

Abstract

Soil carbon is sequestered in soil by plants through photosynthesis and may be stored as soil organic carbon. The increased levels of carbon sequestration may be observed with plants grown on fertilized land. Rainfall and temperature have by far the strongest influence on soil organic matter levels. Increases in temperature have been demonstrated in empirical studies to increase soil heterotrophic respiration and decrease the amount of carbon the soil may uptake. Soil organic matter content is usually higher where rainfall is higher and temperatures are cooler. To analyze the effects of seasonal variations on physico-chemical and biological properties of different forest soil types, a comparative study was conducted to assess the relationship among soil parameters in Murree, Islamabad-Pakistan. Samples were collected from the different forests in the vicinity of Islamabad in all four seasons. Physical, chemical, and biological properties of the soil were analyzed. Results of the study shows that Soil Microbial Biomass (MBS) is highest during summers season while lowest during the winter season for Murree samples. In winter season 380 mg/kg Phosphorus concentration was observed in NUST samples which is highest while it decreases in summer season. Total Nitrogen (TN) of 0.421% was observed at Margalla site in autumn season which is the highest, while during the summer season, TN was reduced to 0.211%. Highest Total Organic Carbon (TOC) was observed in Margalla during winter season whereas the lowest TOC was observed in NUST samples during summer season. Statistical analyses reveals that the TOC has a positive co-relation with MBS, WHC and TN, while MBS had a positive correlation with TOC and Temperature. Negative Correlation was found between soil moisture content and temperature.