STUDY OF THE IMPACT OF ENVIRONMENTAL HABITATS ON THE SEASONAL DISTRIBUTION OF MINERAL ELEMENTS IN ROOTS OF SOME MEDICINAL PLANTS IN ARAFAT AREA, KINGDOM OF SAUDI ARABIA

This study aimed to assess the impact of habitat on the distribution of the elements of commonly used medicinal plants that grow in the area of Arafat, Saudi Arabia. The study areas represented by ten sites to include five habitats (two sites per habitat). The habitats were selected based on the type of soil, type of vegetation and topography of the soil. The soil in the area of Arafat includes: sand dunes (habitat 1), easy rock (habitat 2), Valley (habitat 3), a transition zone between sand stones and easy rock (habitat 4) and the plains of rock covered with loose sand (habitat5). Samples were taken from the soil of the sites from two different places inside the habitat to a depth of 30 cm. The most famous medicinal plants were selected to conduct the study; these are Rhazya stricta, Rhanterium epapposum, Cassia italca, Cassia senna, Citrullus colocynthis and Abutilon pannosum. Measurements in soil included, pH, Electrical conductivity (EC) and the amount of some heavy elements (zinc, copper and manganese), In addition, sodium, calcium, potassium and magnesium have been determined in roots of the medicinal plants, during two periods, named as: the first winter and second winter, except for soil texture where results were taken three times a year including summer. The results revealed that, potassium was high in expense of sodium element in Arafat area plants, especially in Rhazya stricta all over the year. It was observed that the soil texture is characterized by high sand contents which increase in winter compared to summer. We concluded that the soil texture and mineral elements are the limiting factors for distribution of medicinal plants in Arafat area.