eng International Academy of Ecology and Environmental Sciences Proceedings of the International Academy of Ecology and Environmental Sciences 2220-8860 2015-06-1 5 2 70 76 2 article Mohammad Hassan Sayyari-Zahan msayari@birjand.ac.ir, mh.sayyar@gmail.com 1 AbdolHamid Gholami 2 Somayeh Rezaeepour 2 Department of Soil Science, Faculty of Agriculture, University of Birjand, Birjand, Iran Department of Soil Science, Faculty of Agriculture, University of Birjand, Birjand, Iran Application of conventional fertilizers has been contributing much pollutant to the environment. This study aimed to assess the potential of diatomite and re-use coal waste as a non chemical fertilizer to environmental improvement. The experiments were evaluated in 2kg pots under greenhouse conditions at 4 levels of diatomite powder including 0, 10, 20, 40 g/kg soil as well as 5 levels of coal waste powder including 0, 20, 40, 80, 160 g/kg soil based on completely randomized design with three replications. Treatments of diatomite and coal waste were mixed well and kept under field capacity moisture for 4 months. The results showed that the effects of diatomite and coal were significant on EC, K and P concentrations in soil while the coal waste showed more influenced on decreasing of soil pH. Adding diatomite up to 40 g/kg in soil increased EC, K and P viz. 2.92, 1.19 and 1.54 times respectively compared to control sample. Using of 160 g/kg of coal in soil increased EC (2.89 times) and decrease pH (1.06 times) which had led to increased availability of trace elements that enhance plant growth. The highest bio-available concentrations of K and P in soil obtained at 80 and 40 g/kg of diatomite and coal waste respectively. This study demonstrates that a good fertilizer can be produced by using diatomite and coal waste; however, further research is required. http://www.iaees.org/publications/journals/piaees/articles/2015-5(2)/diatomite-and-re-use-coal-waste-for-fertilizer.pdf diatomite coal waste phosphorus potassium EC pH