EFFECTS OF LAND-USE MANAGEMENT ON SURFACE SOIL PROPERTIES, EROSION INDICES AND GREEN TEA YIELD IN HUMID BLACKSEA REGION

Many basins with forest eco-systems in the north-east of Turkey have been converted to agricultural catchments, to which varying quantities and types of manure have been applied. The objectives of this study were to investigate the effects of land-use on surface soil properties in four adjacent management types: Alder coppice (control), and three types of tea cultivation management (at the first: compound fertilizer and stable manure, besides mulching; at the second, compound fertilizer and stable manure; and at the last one, only compound fertilizer) were applied to assess the impact of long-term cultivation and mulching on green tea yield. A total of 80 soil samples (4 replications x 4 treatments x 5 soil sample points) were collected from 0-10 cm soil depth for laboratory analyses. Results according to land conversion and land-use types showed that the plant-available water (PAW), saturated hydraulic conductivity (Ksat), wet stable aggregates (WSA), soil organic matter (SOM), soil organic carbon (SOC) and green tea yield decreased significantly, while clay, permanent wilting point (PWP), bulk density (Db) and soil penetration resistance increased significantly. The highest soil degradation was determined in TC-III (only compound fertilizer). The results indicate that an accurate planning and land management model is required. This would consider the characteristics of existing, land areas, help to conserve soils in tea plantations, and ensure that tea cultivation is carried out sustainably.