SPATIAL VARIATION OF THE SOIL AND WATER QUALITIES IN THE MOUNTAIN LAKES AT DIFFERENT ALTITUDE OF ARUNACHAL PRADESH, INDIASantoshkumar Abujam, Dhoni Bushi, Karo Jongkey, Oyi Dai Nimasow, Gibji Nimasow and Debangshu Narayan Das
A rapid assessment of certain water and soil quality parameters were undertaken in different lakes covering 4 districts of Arunachal Pradesh from the month of May, 2019 to March, 2020. The sampling and analysis were performed following the standard methods and recommended protocols for each of the parameters. The results indicate maximum pH value of 7.9 in the high altitude Kyalem Lake in Tawang and minimum of 7.0 in the low altitude Bone Lake in Upper Siang. The value of highest dissolved oxygen (11.55 mg/L) was found in Hireng Lake of Upper Siang and lowest (1.15 mg/L) in PTsho Lake of Tawang whereas the highest value of free carbon dioxide (1.3 mg/L) was recorded in Nagula Lake of Tawang and lowest (0.2mg/ L) in Pegu Lake of Upper Siang. The highest alkalinity (7.8 mg/L) was found in Bone and lowest (1.4 mg/ L) in Kyalem; the highest hardness (19 mg/L) was found in Pegu and lowest (3.5 mg/L) in Mehao. Among the soil parameters, the highest moisture of 69% was recorded in Pegu and the lowest of 61% in Shungatser (Tawang); the highest water retention capacity (0.92 mg/L) was found in Ganga and the lowest (0.8 mg/L) in Mehao and the higher soil pH around 6.9 was recorded in lakes of Sela, Nagula and Shungaster (Tawang) while the lowest value of 5.0 was found in Kyalem. The values for available soil nitrogen, phosphorus, potassium and organic carbon showed fluctuations in accordance with the altitudinal variations of lakes. Further, the soil texture was also observed to be mostly sandy loam and clay loam in majority of the lakes. The results obtained from the water quality and soils of studied lakes revealed that there was distinct slight variation among the lakes due to the altitudinal variation.