Ecological Assessment of some Trace Elements Status in North Sinai

Abstract

The accumulation of trace elements in cropland soils poses a growing threat to sustainable agriculture development, and their dynamics throughout ecosystem components are among the most complicated issues to study and the most expensive to remediate. Hence, this paper proposes the forward mass balance modelling of any element as an approach to monitor and assess its status in cropland ecosystem, and to predict long-term results by computer simulations. Status of Fe, Mn, Zn, Cu, Ni, Mo and B in wheat and broad bean crops, irrigation water, fertilizers, and soil from North Sinai were investigated. The concentrations of the studied elements were within the permissible limits in most cases and beyond those limits in some cases. The seasonal input by irrigation and by fertilizers of each element was determined and the output by harvested crops and through leachate was estimated, all in units of g.ha -1 and g.kg -1 . Also, the baseline values of the studied elements in the study area were reported for future reference as well as the mathematical description of the proposed approach. The quantitative profiling indicated that the current land use has increased soil content of Mn, Zn, Ni, Mo and B. Irrigation water was identified as the cause of soil enrichment with B and Mo; manure was the main source of Ni and Zn; while both were the main sources of Mn. The equilibrium between the input and the output was found to be the status of Fe and Cu. Analysis of the results showed the need to an interactive multi-criteria risk assessment framework in which considers all ecosystem components and the local conditions.