Abstract

The study aims to evaluate the effect of altitude on soil properties in agricultural landscape of East Siang, Eastern Himalaya. Four study sites along the altitude namely, Ruksin (<150 m asl), Pasighat (150 to 300 m asl), Mebo (300 to 450 m asl) and Pangin (>450 m asl) were selected. Soil samples were collected on seasonal basis during 2009 to 2011 for analysis of physico-chemical properties. The results obtained were statistically analyzed using STATISTICA 6. Study revealed that soil texture was loamy sand to sandy loam. Bulk density, soil porosity and available Phosphorous were higher in lower altitude study sites; however soil moisture and available Potassium showed reverse trend. Water holding capacity was lower in upper soil surface except in sites at Pangin. Soil was slightly acidic in nature at all sites. Soil organic carbon (SOC), soil organic matter (SOM) and Total Kjeldahl Nitrogen were higher in mid altitude. All the study sites showed low C:N ratio. Differences in parameter of soil properties at different years, sites, seasons, soil depths and in combination of these factors were significantly different except in moisture, SOC and SOM in year and soil depth combination. Based on the result, it can be concluded that soil fertility was better in mid altitude.

Key words: Agricultural landscape, east Siang, eastern Himalaya, soil dynamic, soil physico-chemical properties.