University of Córdoba (Spain)

About: University of Córdoba (Spain) is a education organization based out in Cordova, Spain. It is known for research contribution in the topics: Population & Catalysis. The organization has 12006 authors who have published 22998 publications receiving 537842 citations. The organization is also known as: University of Córdoba (Spain) & Universidad de Córdoba.

Phosphorus Forms and Desorption Patterns in Heavily Fertilized Calcareous and Limed Acid Soils

Abstract: Phosphorus desorption from fertilized soils is significant for agriculture and the environment. This study was aimed at characterizing the forms in which P occurs in calcareous and limed acid soils and their influence on P desorption patterns. The P forms of two limed acid and three calcareous soils of Europe were characterized by chemical extraction, isotopic exchange, and sequential fractionation. Phosphate desorption was studied using resins and goethite as ion sinks. Total P ranged from 705 to 1400 mg kg -1 . Isotopic exchange revealed more surface-adsorbed P in the limed acid than in the calcareous soils. Calcium phosphates predominated in the calcareous and Al and Fe phosphates in the limed acid soils; one limed add soil contained significant amounts of Ca phosphates. The mixed cation and anion exchange resins (ACER) were more effective in desorbing P than the anion exchange resin (AER) and goethite. The desorption curves indicated significant differences in the degree of homogeneity of the P desorption reactions, the greatest and lowest degree of homogeneity corresponding with calcareous soils. The proportion of ACER-extractable P that was plant-available P was >50% for the limed acid and 60% for the limed add and <40% for the calcareous soils. Plant P availability was thus poorer in the calcareous soils than in the limed acid soils.

Heavy metal uptake from greenhouse border soils for edible vegetables

Abstract: Six essential elements, cadmium and lead were determined in some horticultural species cultivated in greenhouse borders by atomic absorption spectrophotometry to evaluate the contribution of these vegetables to the daily intake of cadmium and lead in Spain. The existence of significant differences (P 0.05) between the concentration of the soil and that of corresponding vegetable species was found. The heavy metal uptake from soil to plants is a function of the physical and chemical nature of the soil and is altered by innumerable environmental and human factors. If the mean levels of cadmium and lead (0.029 mg kg−1 and 0.221 mg kg−1 respectively) are taken into account, the daily intake contribution of these metals will be 1.4 μg day−1 for cadmium and 11 μg day−1 for lead.