عنوان مقاله [English]
In order to investigate the effect of Sewage Sludge (SS) application on the amount of micro elements in soil and absorption of these elements in plant organs of medical plants mint (MenthaPipperata), an experiment was carried out in split plot based on a complete randomized block design in three replications in the field of the University of Agricultural Sciences and Natural Resources of Sari. Five levels of fertilizer treatments (T1= control, T2= 20 tons per hectare mix SS and 1/2 fertilizer, T3= SS 20 tons per hectare, T4= 40 tons per hectare mix SS and 1/2 fertilizer and T5= SS 40 tons per hectare) and six levels of fertilizer years one year fertilizer (1385), two unconsecutive years fertilizer (1385 and 1387), two consecutive years fertilizer (1385 and 1386), three unconsecutive years fertilizer (1385, 1386, 1388), three consecutive years fertilizer (1385, 1386 and 1387) and four consecutive years fertilizer (1385, 1386, 1387 and 1388) were considered. The fertilizer treatments were carried out before planting in the land. The results of these tests showed that as the level of consumption and Sewage Sludge increased, the amount of absorbent micro-elements in the soil and the concentration of these elements in the mint plant increased. Most of too the micro-dements were observed in the 40 tons/ha treatment of SS in three consecutive years with more consumption compared to others. The interaction between the years of fertilizer consumption and fertilizer treatment on the rate of absorbent micro-elements except Mn in the soil and root of mint were significantly different, where, as, in the plant leaves, the interactions had a significant effect on the amount of Mn, but no significant effect was observed in the absorption rate of Cu, Fe and Zn.