Environmentally safe release of plant available potassium and micronutrients from organically amended rock mineral powder

Abstract

The staggering production of rock dusts and quarry by-products of mining activities poses an immense environmental burden that warrants research for value-added recycling of these rock mineral powders (RMP). In this study, an incubation experiment was conducted to determine potassium (K) and micronutrients (Zn, Cu, Fe and Mn) release from a quarry RMP to support plant nutrition. Four different size fractions of the RMP were incubated with organic amendments (cow dung and legume straw) under controlled conditions for 90 days. Samples were collected at different intervals (7, 15, 30, 45, 60 and 90 days) for the analysis of available K and micronutrients in the mineral-OM mixtures and leachates. There was a significant (p \0.05) increase in pH of leachates from the mineral-OM mixtures. The K release was significantly higher from the finer size fraction of RMP. About 18.7% Zn added as RMP was released during the incubation period. Zn release increased from 4.7 to 23.2% as the particle size of RMP decreased. Similarly, Cu release from RMP increased from 2.9 to 21.6%, with a decrease in the particle size. Fe and Mn recovery from RMP recorded 11.2 and 6.6%, respectively. Combined application of OM and RMP showed significantly higher nutrient release than other treatments. This study indicates that effective blending of RMP with organic amendments could be a potential source of K and micronutrients in agriculture without posing a risk of toxic element contamination to the soil.

Macro and Micro Nutrients Status in Soil under Application of Vermicompost, Zn and Fe Fertilizers in Maize Crop

“…Table 3 was indicated that incremental levels of zinc showed nonsignificant increase on available status of potassium over control (Zn0) during both the years. These findings are enline to the findings of Ranpriya et al [26] and Basak et al [27].…”

Effects of biotite syenite on the nutrient levels and electrical charges in a Brazilian Savanna Ferralsol

“…Biotite is a faster-release K silicate source than K-feldspar (Mohammed et al 2014), and this may be strategic in the management of these sources, in relation to the residual effect. Rocks with these minerals are common in many countries and can be used as a model for studying the behavior of silicate minerals with potential to provide K for agriculture (Basak et al 2020).…”

Unveiling the Solubilization of Potassium Mineral Rocks in Organic Acids for Application as K-fertilizer

“…They are formed by tetrahedral silica and aluminum groups, strongly linked together by cations, with the K inserted in the crystalline structure, making it difficult to extract (12). As a consequence, the dissolution process of this mineral in the soil involves complex reactions and mechanisms, which limits its application as a natural fertilizer once it does not meet the minimum nutritional demands required by plants (21,22). A better understanding about the action of microbial organic acids on highly available minerals such as K-feldspar could contribute to promote their use as natural fertilizer.…”