Showing 5 results for Organic Fertilizer
E. Khadivi Borujeni, F. Nourbakhsh, M. Afyuni, H. Shariatmadari,
Volume 11, Issue 1 (4-2007)
Abstract
Application of sewage sludge on the farmland as a source of crop nutrient had recently received considerable attention. Some management practices may be required to control the accumulation of toxic elements including Pb, Ni and Cd. Sequential extraction gives useful information on plant bioavailability of the elements. The objective of this study was to investigate the cumulative and residual effects of sewage sludge application on the chemical forms and mobility factor of Pb, Ni and Cd. Zero, 25, 50 and 100 Mg ha-1 of sewage sludge were applied for 1, 2 and 3 consecutive years in a split plot design, with three replications. Soil samples were taken from 0-20 cm at the end of the third year of application. Different chemical forms of Pb, Ni and Cd were measured. Results revealed that the soluble form (SOL) of Ni and Cd increased whereas Pb soluble form decreased with increasing levels and years of application. Exchangeable (EXC), carbonate (CAR) and organic (ORG) forms of the three elements increased as levels and years of application increased. Occluded (OCC) form decreased for Pb, Ni and increased for Cd. Residual form (RES) of Pb increased while that of Ni and Cd decreased. A gereral increase was observed for available (DTPA-extractable) concentration of Pb, Ni and Cd. Relative distributions of different chemical forms were in the following order: Pb: OCC > RES> ORG> CAR> EXC> SOL, Ni: RES> ORG> OCC> CAR>EXC> SOL and Cd: OCC> CAR> RES> ORG> EXC> SOL. The comparison of different forms of the metals showed the following orders: soluble Ni>Pb>Cd, exchangeable, carbonate and occluded Pb>Ni> Cd, organic and residual Ni> Pb>cd. Increasing the available (DTPA-extractable) concentration of the elements in such a calcareous soil showed that consecutive application of sewage sludge may increase the available (DTPA-extractable) concentration beyond critical levels. A significant corretation was observed between organic form and available (DTPA-extractable) concentration of the elements.
H. Dehghan-Menshadi, M. A. Bahmanyar, S. Salek Gilani, A. Lakzian,
Volume 16, Issue 60 (7-2012)
Abstract
Biological indicators are considered soil quality elements, due to their dependence on soil organisms. In order to investigate The effect of compost and vermicompost enriched by chemical fertilizers and manure on soil organic carbon, microbial respiration, and enzymes activity in basil plant's rhizosphere, a field experiment was conducted as a split-plot design with randomized complete blocks and three replications in 2006. The main plot involved six levels of fertilizer including: 20 and 40 tons of compost enriched, 20 and 40 tons of vermicompost enriched per hectare, chemical fertilizer and control without fertilizer and sub-plot, and period of application (two, three and four years). The results showed that application of compost and vermicompost at all levels increased soil organic carbon (OC) and soil microbial respiration, microbial biomass and urease activity compared to the controls (p<0.05), but increasing trend among the treatments was not similar. The maximum amounts of OC, soil microbial respiration and enzyme activity were observed in 40 tons of vermicompost enriched with chemical fertilizer ha-1 with four years of application. In high levels of compost application, the urease activity was decreased.
M. Norouzi, A. H. Khoshgoftarmanesh, M. Afyuni,
Volume 18, Issue 70 (3-2015)
Abstract
Organic fertilizers affect soil chemical and physical properties, particularly chemical forms of zinc in soil solid phase and thereby improve soil Zn availability. The present field study was aimed to evaluate the effects of organic and chemical fertilizer (zinc sulfate) on different zinc fractions in soil solid phase of rhizosphere in two successive years in Rudasht Research Field, Isfahan. Treatments consisted of sewage sludge (5 and 10 t ha-1), cow manure (5 and 10 t ha-1), and ZnSO4 (40 Kg ha-1). The control had no added Zn. Three weeks after applying fertilizer treatments, Back Cross genotype of wheat was cultivated in each plot. Our results showed that the organic fertilizers increased Zn concentration in exchangeable fraction (EXCH-Zn), the organically bound Zn form (ORG-Zn), and Zn bound to iron and manganese oxides (FeMnOX-Zn). However, the changes in Zn fractions were dependent on the fertilizer type. Positive and significant correlation between EXCH-Zn, ORG-Zn, and FeMnOX-Zn, and the total Zn uptake by wheat indicated that these pools of Zn in solid phase are labile pools with a significant role in supplying Zn for plants.
S.a. Ghaffari Nejad, F. Moshiri, S.m. Mousavi,
Volume 29, Issue 2 (7-2025)
Abstract
This study was conducted to evaluate soil fertility management scenarios including separate use of chemical and organic fertilizers (animal manure and municipal waste compost) and their integrated application on changes in the amount of available nitrogen, phosphorus, and potassium in the soil from November 2017 for four years in six consecutive crops at the Agricultural Research Station of the Soil and Water Research Institute. The results showed a depletion of 14 and 44% of soil available nitrogen and phosphorus, and no depletion of available potassium in the treatment without fertilizer in six consecutive cultivations. Annual consumption of 20 t ha-1 of municipal waste compost and 75% of the recommended nitrogen showed the highest amount of soil-available nitrogen. Unlike phosphorus, the amount of soil available nitrogen in municipal waste compost treatments was significantly higher than in cattle manure. The highest available soil phosphorus was in the treatment with 10 t ha-1 of cattle manure before each crop, and the average available phosphorus in six consecutive cultivations was significantly higher than in the other treatments. The use of 10 t ha-1 of cattle manure and municipal waste compost before each crop resulted in the highest accumulation of potassium in the soil, respectively. The available soil potassium in cattle manure treatments was significantly higher than in municipal waste compost. The results of this experiment indicated the importance of using fertilizers containing nitrogen, phosphorus, and potassium in maintaining soil fertility stability in the long term.
M. Goosheh, A. Azadi,
Volume 29, Issue 3 (10-2025)
Abstract
Soil organic carbon provides conditions for better plant growth by increasing soil quality by improving physical, chemical, and biological properties of the soil. Therefore, an experiment was conducted in a randomized complete block design (RCBD) with three replications at the Shavour Agricultural Research Station in Khuzestan Province to investigate the effect of different sources of organic matter on some soil properties and wheat yield. The main plots included cow manure, poultry manure, wheat straw, bagasse, and sugarcane filter cake, and the subplots included three fertilizer levels of 2.5, 5, and 10 tons per hectare. Also, one plot was considered as a control (without organic fertilizer) in each replication. The results showed that the best sources of organic fertilizer available in the province that have had a favorable result in increasing wheat yield and improving soil physical properties are filter cake, cow manure, and sugarcane bagasse fertilizers (with a yield of 4772, 4467, and 4452 kg/ha, respectively). Wheat straw also has the least effect on yield (4019 kg/ha) and plays a major role only in improving soil physical and chemical properties. It is worth noting that since no significant difference was observed between the fertilizer consumption amounts in the overall results, the consumption of 2.5 tons per hectare of each fertilizer source is more economical and is recommended. It also seems that the combined application of filter cake with sugarcane bagasse or cow or chicken manure with wheat straw and stubble, in a total amount of 2.5 tons per hectare, has a more favorable result in increasing wheat yield and improving soil physical properties.
