Variation in methanotrophic bacterial population along an altitude gradient at two slopes in tropical dry deciduous forest

Soil samples were collected from Panchamarhi dry deciduous forest in Satpuda Biosphere Reserve, India to determine the effect of hill slopes and altitude on the population size of methanotrophic bacteria. Population size, in range of 4×105–3.6×107 g−1 dry soil, was negatively correlated with altitude and increased exponentially ( r 2 = 0.97 , P<0.001) at steep slope (60°) while logarithmically ( r 2 = 0.97 , P<0.001) at low slope (45°). Soil organic C, total N, and soil moisture increased while C/N ratio and temperature decreased down the hill slope. The results indicated that nutritional status of the soil across the slopes determines the methanotrophic bacterial population size.