The relationships between ph status of soil in tea plant cultivating provinces and soil properties in Turkey

Tea plant is grown only in the area starting from the Georgian border and extending to Fatsa in the West in Turkey. It is desirable that the soils cultivated for tea plant should be acid reactive. Tea plant develops optimally in soils ranging from pH 4.5 to 6.0. When the pH in the soil decreases below 4.0 for any reason, the tea plant cannot develop normally and quality fresh leaves cannot be produced. Therefore, qualified black tea cannot be obtained. In our study, the relationships between the pH status of tea plant cultivated soils and their distribution according to tea plant cultivated regions and some soil properties were investigated. For this purpose, a total of 532 soil samples were taken respectively; 58 from Artvin, 361 from Rize, 101 from Trabzon and 12 from Giresun, taking into account the distribution of the tea plant plantations. According to the results of the research, it was determined that pH values of tea plant cultivated soils ranged between 3,29-5,59. Variations in soil reaction was found to be between 3.95-5.51 in Artvin, 3.48-5.59 in Rize, 3.29-5.45 in Trabzon and 3.84-4.66 in Giresun. It was determined that the pH of the soils cultivated in the Eastern Black Sea Region was below pH 4.49 in 53.95% and in the range of 4.50-6.00 which was the optimum pH value in 46.05%. The distribution of soils with pH below 4.49 in Artvin, Rize, Trabzon and Giresun provinces were determined as 22.41%, 54.57%, 67.32% and 91.67%, respectively. The distribution of soils having optimum reaction (pH 4.50-6.00) for tea plant cultivation were determined as 77.59%, 45.43%, 32.68% and 8.33% for Artvin, Rize, Trabzon and Giresun provinces respectively. Significant positive correlations were determined between soil pH and replaceable potassium, calcium, magnesium, available zinc, copper and manganese concentrations in the soil due to the increase in soil reaction from strong acid to weak acid. When the region is analyzed in general, it is seen that the low pH of the soils cultiva