The distribution and coexistence of some wild plants in relation to mineral nutrient availability in a high sodium polluted site in central Sudan

The factors affecting the distribution and coexistence of Cyperus laevigatus, Typha angustata and Paspalum viginatum, in a high sodium polluted site in central Sudan, were investigated. The high sodium content of the site was mainly due to effluents from a near by textile factory where high quantities of Na compounds, like: NaOH, Na2CO3, Na2SiO3 and NaHCO3 were used in the textile processes. The investigation was carried out by chemical analysis of soil and plant samples and computation of correlation coefficients between soil nutrients and ion uptake by the investigated plants. Soil and plant samples, from the investigated site, were collected from 35 sampling points of 80 x 120 m rectangular grid, each point is 20 m distant from the other neighboring points. Soil chemical analysis data showed that the investigated site was moderately alkaline and characterized by very high content of Na, reasonably high content of Ca, adequate quantities of Mg, K and Fe, low content of NH4-N and P and very low content of Mn. The plant chemical analysis results clearly reflect the different nutritional requirements of the examined plant species. Correlation analysis between soil nutrients and ion uptake by the investigated plants showed that the uptake of a mineral ion by any of the three investigated plant species may be accelerated, slowed down, or may have no obvious effect by another ion in the soil. Moreover, correlation and regression analysis clearly reflect the different patterns of mineral nutrient uptake by the investigated species and hence niche differentiation and coexistence between the investigated species in the investigated site.