EFFECT OF ECOTOURISM ON PLANT DIVERSITY, SOIL AGGREGATE STABILITY AND PARTICULATE ORGANIC MATTER IN NATIONAL KHOJIR PARK IN TEHRAN

Abstract

This work assesses the effects of ecotourism on biodiversity, soil POM and ASI in a semi-arid region in Iran. Three zones as High-pressure (0 to 50 m from the road, visitors density: > 20 persons ha^-1 day^-1), Mid-pressure (50 to 100 m from the road, visitors density: 5-20 persons ha^-1 day^-1), and Low-pressure (100 to 150 m from the road, visitors density: < 5 persons ha^-1 day^-1) ecotourism were selected. Indicators of biodiversity, richness, and evenness (0.77, 5.55, and 0.79, respectively) were significantly higher in the High-pressure zone. Soil bulk density (1.95 g m³ ), pH (7.98), and EC (0.82 ds m^-1) were significantly higher in the High zone whereas a higher content of total C (0.39%), total N (0.13%), available P (4.83 mg kg^-1), available K (3.21 mg kg^-1), available Ca (34.91 mg kg^-1), and available Mg (5.66 mg kg^-1) were found in the Low-pressure zone. POM-C and POM-N were significantly followed by Low (0.21 and 0.03 g kg^-1) > Mid (0.14 and 0.02 g kg^-1) > High (0.08 and 0.01 g kg^-1) zones, respectively. The Low-pressure zone with a population density of only 5 people per ha is associated with enhanced soil biodiversity and nutrient cycles.