Search

With regard to the low cation-exchange capacity and large saturated hydraulic conductivity of sandy soils, a field experiment was carried out in 2006–2007 to determine the impact of zeolite on nitrogen leaching and canola production. Four nitrogen (N) rates (0, 90, 180, and 270 kg ha–1) and three zeolite amounts (3, 6 and 9 t ha−1) were included as treatments. The results demonstrated that the highest growth parameters and seed yield were attained with 270 kg N ha−1 and 9 t zeolite ha−1. However, the highest and the lowest seed protein percentage and oil content were obtained with 270 kg N ha−1 accompanied by 9 t zeolite ha−1, respectively. Nitrate concentration in drained water was affected by nitrogen and zeolite. The lowest and highest leached nitrate values were found in control without N and zeolite (N0Z0) and in treatments with the highest N supply without zeolite (N270Z0), respectively. In general, nitrogen-use efficiency decreased with an increase in N supply. Application of 9 t zeolite ha−1 showed higher nitrogen use efficiency than other zeolite amounts. Also, application of more N fertilizer in soil reduced nitrogen uptake efficiency. In total, application of 270 kg N ha−1 and 9 t zeolite ha−1 could be suggested as superior treatment. [ABSTRACT FROM AUTHOR]

A field experiment was carried out in a semi-arid region of Iran during the 2006–2007 growing season to investigate canola seed yield as affected by nitrogen (N) and natural zeolite (Z) rates. This experiment studied N efficiency and N leaching loss in a sandy soil. Experimental treatments consisted of a factorial combination of three N levels (90, 180, and 270 kg N ha−1) and four zeolite rates (0, 3, 6, and 9 t zeolite ha−1). The result showed that the greatest seed yield (2452.3 kg ha−1) was obtained from the N270Z9 treatment whereas the control treatment (N0Z0) produced the lowest seed yield (1038.3 kg ha−1). Moreover, use of 270 kg N ha−1 without zeolite (N270Z0) led to the greatest amount of N leaching loss (144.23 kg ha−1). Zeolite application clearly reduced N leaching loss in all N rates. This justified low N-use efficiency in high N applications. More N uptake and more canola seed yield is attributed to zeolite application. [ABSTRACT FROM AUTHOR]

Nitrate leaching from agricultural soils represents substantial losses of N from fertilizer. Nitrogen leaching in sandy soil decreases fertilizer efficiency and can depress crop production. Materials with high cation-exchange capacity are hypothesized to reduce N leaching and increase N uptake in sandy soils. This randomized complete-block design study evaluated the influence of chemical, organic, and integrated fertilizer treatments and natural zeolite on growth, yield, and grain mineral content of wheat (Triticum aestivum L.) grown on sandy soils. Supply of N by urea and composted cattle manure amended with 10% (w/w) zeolite increased wheat growth, yield, and yield components. Similar results were obtained when zeolite was applied directly to soil. The highest grain Zn, Fe, and Mn contents were achieved in plots treated only with organic fertilizers. Chemical plots produced the highest N and protein content. Integrated fertilizer treatments amended with zeolite are an effective and environmentally sound method to improve wheat yield. [ABSTRACT FROM PUBLISHER]

A comparative field experiment has been conducted in order to study the effect of chemical, organic and integrated nitrogen suppliment on micro and macro nutrient residue after wheat harvesting, at Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran. The treatments consisted in three groups that are chemical, organically and integrated of them. Nitrogen was supplied in different proportion from chemical and organic sources. Also, zeolite was applied in two ways: mixed with soil and mixed with cattle manure during composting. Before sowing and after wheat harvesting, macro and micro nutrient availability in the soil were examined. The results showed that, among treatments supplying with 100% nitrogen required from composted cattle manure amended with 10% (w/w) zeolite had the best effect on nutrition residue after wheat production because zeolite decreased nitrogen leaching during the manure composting. Crop yield was not sratistically different between fertilizer treatments but the highest seed yield was achieved from supplying 50% nitrogen required from cattle manure compost and 50% by urea amended with 10% (w/w) zeolite. This study demonstrated that composted cattle. manure amended with zeolite improves soil fertility after wheat production compared with chemical fertilization. [ABSTRACT FROM AUTHOR]