• Journal of Forest and Environmental Science
• /
• v.32 no.1
• /
• pp.20-26
• /
• 2016

DTPA (Diethelene-triamine pentaacetic acid) extractable micronutrients of surface soil samples from six different locations of Cox's Bazar and Chittagong districts were studied. All the soils under study were sufficient in DTPA extractable Fe, Mn and Cu contents. The available Zn contents in soils of Dulhazara, Chengchhari and Faissakhali under study were also above the critical limit while soils at Fulchhari, Hasnabad and CU were deficient in available Zn. The study also showed that DTPA extractable Fe content had the significant and positive relationships with clay and soil organic carbon. On the hand, negative and significant relationship was observed between extractable Mn and soil pH while DTPA extractable Zn and Cu were positively and significantly correlated with soil organic carbon of the studied area.

• Journal of Forest and Environmental Science
• /
• v.34 no.6
• /
• pp.429-434
• /
• 2018

Extractable iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) contents and their distribution with depths in soils of forested and adjacent deforested areas at Jahazpura, Teknaf, Cox's Bazar of Bangladesh were studied. The soils under forest showed higher levels of DTPA-extractable micronutrients in all three layers of soil in comparison to those of the deforested areas. The differences between forested and deforested sites were, in most cases, significant.. The top soils of forested sites had the higher contents of micronutrient and generally decreased with depth in forested soils, while there was no regular trend of distribution in deforested soils. The study also revealed that contents of extractable Fe, Mn and Cu were sufficient in all depths and sites but Zn was deficient in bottom layer of forested and all three layers of deforested sites. The results suggested that organic matter, clay and soil pH could play important roles in concentrations and distributions of micronutrients in soils of the study areas.

• Korean Journal of Soil Science and Fertilizer
• /
• v.39 no.4
• /
• pp.230-236
• /
• 2006

The objective of this study was to evaluate the effects of the application of compost on the availability of micronutrients in lettuce. Micronutrient contents of manure-based composts containing various other source materials were investigated. Total and extractable contents of micronutrients in the composts were analysed. Pots containing soil of relatively low micronutrient levels were treated with 1,000 and $2,000kg\;10a^{-1}$ of compost and used to grow lettuce plants under greenhouse conditions. Fresh and dry weights of lettuce and micronutrient uptake were determined after harvest. Manure-based composts of various other source materials contained very different amounts of total and extractable micronutrients. Total contents of B, Cu, Fe, Mn, Mo and Zn were in the range of 26-42, 27-160, 4,300-9,500, 290-790, 0-0.5 and $140-420mg\;kg^{-1}$, respectively. The contents of 0.1 N HCl extractable B, Cu, Fe, Mn and Zn were 23-32, 1.3-2.6, <1, 7-32 and 0.5-5% of total content, respectively. Contents of micronutrients extractable in DTPA solution were generally higher than those extractable in 0.1 N HCl. It was found that the fresh and dry matter productions of the plants were significantly higher in the compost treatment of $2,000kg\;10a^{-1}$. Lettuce grown in soil treated 1,000 and $2,000kg\;10a^{-1}$ of manure-based compost contained higher levels of B, Cu, Mo and Zn than lettuce grown without compost application. However, contents of Fe and Mn in lettuce were relatively lower in the compost treatments. In the compost treatments the proportions of micronutrients in soil and plant were all in the optimum ranges and below the toxicity levels. The results obtained allow us to establish that commercial composts could be used as soil amendment for plastic film house crop production with sufficient supply of micronutrients.