Available Forms Of Zn Research Articles

Effect of organic fertilizers on soil organic carbon and risk trace elements content in soil under permanent grassland

Karabcova H., Pospisilova L., Fiala K., Skarpa P., Bjelkova M. (2015): Effect of organic fertilizers on soil organic carbon and risk trace elements content in soil under permanent grassland. Soil & Water Res., 10: 228–235. The effect of different kinds of organic matter inputs on elemental composition, content, and quality of humic sub stances was studied on permanent grassland during 2008–2013. The experiment included two organic fertilizer types – compost and slurry, both with the range of stocking rates 0.9, 1.4, and 2.0 livestock units (LU)/ha (corresponding to 54, 84, and 120 kg N/ha, respectively), and control without any fertilizer. The soil was sandy-loam, of Cambisol type, with semi natural permanent grassland. Labile forms and total contents of selected trace elements (Co, Cu, Zn, Cd) and macroelements (Ca, Mg, K, P, and N) were measured. Soil organic matter parameters such as total organic carbon (C ox ), humic substances (HS), humic acid (HA), fluvic acid (FA), and labile carbon forms ( hot-water extractable carbon ( C hws ), cold water extractable carbon ( C cws )) were determined. Results showed that the greatest content of P, Ca, Mg, and N in the soil was detected by the CO 2.0 treatment. Furthermore, the positive effect of compost on C ox , C hws , HA, FA, HS, N and macronutrients was observed. The elemental analysis of humic acids showed lower carbon content and higher oxygen content in HA molecule, which indicated young humic acids, with a lower condensation degree. The content and quality of humic substances strongly influenced the total and labile trace elements content in the soil. Additionally, hot water soluble carbon significantly correlated with plant available forms of Zn, Cu, and Cd.

Effect of the way set-aside land is maintained on the content of available forms of selected micronutrients in soil.

AbstractIn 1996, a field experiment was set up on class IIIa soil, which consisted of 6 trials:1 – bare fallow, 2 – fallow land seeded with annual plants, 3 – field swarded with goat’srue ( Galega orientalis Lam.), 4 – traditional fallow, 5 – field swarded with a mix of goat’srue ( Galega orientalis Lam.) and aweless brome ( Bromus inermis ), 6 – field swarded withaweless brome ( Bromus inermis ). During the tests, no agrotechnical measures were car-ried out apart from periodical mechanical weeding of the bare fallow and the sowing ofannual plants. Plant samples for chemical analyses were taken from the swarded fields;the remaining biomass was left on the fields. After each growing season, soil samples werecollected in four replicates from the 0-25 cm and 25-50 cm soil horizons, for determinationof the content of Cu, Zn and Mn available forms. This paper discusses the results obtainedin 2000-2007.The experiment has demonstrated that the way farmland was laid fallow or set-asidehad an effect on concentrations of the available forms of Cu, Zn and Mn in the 0-25 and25-50 cm soil horizons. Particularly large changes occurred in the levels of Zn and Mn.The way set-aside arable land was kept had a weaker influence on the concentrationsof easily soluble forms of copper. By seeding annual plants and leaving the grown biomasson a set-aside field, it was possible to maintain the soil abundance of available Zn on a highlevel and that of Cu and Mn – moderately high. Keeping soil as bare fallow favoured bet-ter accumulation of available forms of copper and manganese.Key words: set-aside, fallow, available forms of Zn, Cu and Mn.dr in?. Piotr ¯arczynski, Chair of Agricultural Chemistry and Environment Protection,University of Warmia and Mazury in Olsztyn, Oczapowskiego Street 8, 10-744 Olsztyn,Poland, e-mail: piotr.zarczynski@uwm.edu.pl

Micronutrients as Impurities of Inorganic Fertilizers Marketed in Saudi Arabia

Inorganic fertilizers with major nutrients are likely to be contaminated with some micronutrients. Fertilizers, utilized in Saudi Arabia, were analyzed for their total and water-soluble content of Fe, Zn, Mn and Cu. They represented three categories namely: phosphatic, solid multiple nutrient fertilizers (SMNF) and water-soluble multiple nutrient fertilizers (WSMF). Total iron content in examined fertilizers was higher in phosphatic fertilizers and lower in WSMF. Nevertheless, only a very small portion of the total iron content is likely to be available to plants. It was estimated, on the basis of total content, that almost 2 g of iron would be applied to soil for each added kg of phosphatic fertilizer. The highest total content of Zn was recorded for phosphatic fertilizers. The data suggested that less than half kg of Zn would be accumulated in soil if 500 kg of phosphatic fertilizers were applied in one year. This value however, fell dramatically, to one fourth of the value, when only the available forms of Zn were considered. Fertilizer content of manganese and copper were lower than both Fe and Zn. Micronutrient impurities present in inorganic fertilizers might not have an immediate influence on plant nutrition due to their lower solubility.