title: Physico-chemical qualities of water in high altitude rice fish farming system of Ziro valley, Arunachal Pradesh, India.
abstract: Water in rice fields of mountain valley of Ziro, Arunachal Pradesh was investigated for physico-chemical characterization during rice fish farming season (Kharif) of 2013. Water temperature, dissolved oxygen, biological oxygen demand, free carbon dioxide, nitrate-nitrogen, phosphate-phosphorus, chloride, total hardness, calcium hardness, alkalinity, pH, total dissolved solids, specific conductivity and water depth were studied. This study revealed that the physical parameters of water in rice fields like water temperature, pH, total dissolved solids, specific conductivity and water depth were 23.5-31.3 degrees C, 5.9-6.9, 250.34-370.5 mgl(-1), 437.75-660.33 μScm(-1) and 3.72-16.9 cm respectively. The chemical features like dissolved oxygen, biological oxygen demand, free CO2, nitrate-nitrogen, phosphate-phosphorus, chloride, total hardness Ca hardness, alkalinity were 2.4-12.9 mgl(-1), 1.5-11.1 mgl(-1), 9.7-23.35 mgl(-1), 1.28-3.9 mgl(-1), 0.005-0.539 mgl(-1), 16.6-46.8 mgl(-1), 13.9-34.5 mgl(-1), 9.6-13.53 mgl(-1) and 23.16-43.34 mgl(-1) respectively. On the other hand, investigation on planktonic life forms indicated the presence of 13.5x10(3)-84.9x10(3) indl(-1)" and 1.23x10(3)-4.86x10(3) indl(-1) phytoplankton and zooplankton respectively during the Kharif season. The above physiochemical parameters were found to be conducive for raising fish as companion crop of rice due to occurrence of diversified planktonic life forms in underneath water.
authors.forename: Rajashree
authors.initials: R
authors.lastname: Saikia
authors.forename: Tapati
authors.initials: T
authors.lastname: Das
authors.forename: Debangshu Narayan
authors.initials: DN
authors.lastname: Das
mesh_terms: D000531:Altitude; D000818:Animals; D017756:Aquaculture / Q000379:methods*; D003247:Conservation of Natural Resources; D005399:Fishes / Q000502:physiology*; D006801:Humans; D007194:India; D012275:Oryza / Q000502:physiology*; D044382:Population Groups; D012621:Seasons; D013997:Time Factors