مرکز منطقه ای اطلاع رساني علوم و فناوري - VARIATION OF NO^- 3 AND NO^- 2 CONTENTS IN SOME VEGETABLES DEPENDING ON LAND TOPOGRAPHY

Abstract :

The objective of this study was to investigate the variation of NO^- 3 and NO^- 2 contents in some vegetables depending on topography. For this purpose, a total of 126 fresh vegetable samples were randomly collected from 54 black cabbage, 27 lettuce, 27 spinach and 18 head cabbage plants with three replicates in each topographic position (upland, backslope and footslope parts) in the villages of Bulancak and Şebinkarahisar and the central districts of Giresun province, on October 22, in 2003. The variations in NO^- 3 and NO^- 2 contents of these vegetables were determined and evaluated for human health. NO^- 3 accumulation values in black cabbage, lettuce, spinach and head cabbage grown in footslope position were found to be higher than those of plants grown in upland and backslope positions. The average NO^- 3 contents of the black cabbages grown in the all topographic positions of the locations, except Bahçeli village, were found to be hazardous to human health ( 300 mg NO^- 3 kg^-1, TM). Lettuce grown in all topographic positions of Biroğul village, spinach grown in all topographic positions of Avutmuş and Bağlar villages, head cabbage only grown in backslope and footslope positions of Yedikardeş village were found to be risky in terms of their NO^- 3 contents. According to their NO^- 3 accumulation, the vegetable samples were ordered as; black cabbage lettuce spinach head cabbage. While NO^- 2 contents in black cabbage and head cabbage were found to be low and harmless to human health according to WHO ( 1mg kg^-1, DM), NO^- 2 contents in spinach and lettuce were found to be high and hazardous.