LANDSCAPE AND LANDUSE EFFECTS ON SOIL RESOURCES IN A HIMALAYAN WATERSHED

Abstract

SUSTAINABLE LAND MANAGEMENT DECISIONS AT ALL SCALES REQUIRE SOLID, SCIENCE - BASED INFORMATION. SOIL QUALITY ASSESSMENT CAN PROVIDE THIS REGARDING SOIL PHYSICAL, CHEMICAL AND BIOLOGICAL CHARACTERISTICS AND THE ABILITY TO PROVIDE ECOSYSTEM AND SOCIETAL SERVICES. OUR OBJECTIVE WAS TO MAKE A REGIONAL ASSESSMENT OF SOILS IN THE GARHWAL HIMALAYAS TO DETERMINE THEIR ABILITY TO PERFORM VARIOUS FUNCTIONS AND RESPOND TO EXTERNAL INFLUENCES. FIVE FUNCTIONAL CATEGORIES WERE ASSESSED USING 13 SOIL PARAMETERS FOCUSED ON ECOLOGICAL SUSTAINABILITY . HUMAN LAND USE EFFECTS ON SOILS WERE REFERRED TO NATURAL WOODLANDS AT EACH LANDSCAPE POSITION. WITHIN UPPER SLOPE REGIONS, FLORA AND FAUNA HABITAT, MOISTURE RETENTION , ORGANIC MATTER AND NUTRIENT CYCLING, AIR AND WATER INFILTRATION AND RESISTANCE TOEROSION DECREASED 35,27, 24,AND 9% RESPECTIVELY. AT MID - SLOPE POSITIONS THE ORDER AND MAGNITUDE OF DECREASE WERE ORGANIC MATTER AND NUTRIENT CYCLING, FLORA FAUNA HABITAT AND MOSITURE RETENTION (26,22 AND 16% RESPECTIVELY) . CHANGES WITHIN THE VALLEY WERE LOWEST AVERAGING - 3% FOR FLORA AND FAUNA HABITAT AND 13% FOR ORGANIC MATTER AND NUTRIENT CYCLING. WE CONCLUDE THAT THE MINIMUM DATA SET (MDS) USED PROVIDED A REPRESENTATIVE ASSESSMENT OF SOIL QUALITY AND COULD SERVE AS A BASIS FOR ASSESSMENT IN SIMILAR TROPICAL WATERSHEDS.