Evaluating the Effect of Bacterial Inoculation and Fertilization on the Soil Nutrient Status of Coal Mine Soil by Growing Soybean (Glycine max) and Shrub Lespedeza (Lespedeza bicolor)

Abstract

Revegetation with fast-growing N-fixing leguminous plants can be an alternate for reclamation of degraded coal mining areas. Selection of appropriate plant species is an important factor in deciding the success in the remediation of mine spoil. Thus, this study was carried out in greenhouse conditions to evaluate the effect of two N-fixing leguminous plant seedlings, soybean (Glycine max) and shrub lespedeza (Lespedeza bicolor), on the available N and other soil nutrients (P, K, Ca, and Mg) of the experimental coal mine soil. Four treatments, including T0—non-fertilized non-inoculation (control), T1—fertilization, T2—bacterial inoculation, and T3—combination of fertilization and bacterial inoculation with three replications were applied to both plants. Concentration of NH4+-N and NO3−-N increased significantly in the soil at different treatments for both soybean and shrub lespedeza, as compared to control, but apart from control no significant difference was observed between other treatments of increased NH4+-N for soybean and increased NO3−-N for shrub lespedeza. The highest number of nodules and dry weight of nodule per plant (g) was recorded 5.73 and 1.8, respectively in soybean, and 7.77 and 2.76, respectively, in shrub lespedeza with bacteria-inoculated treatment (T2), whereas fertilized treatment (T1) produced the lowest number of nodule and dry weight of nodule in both plants. Increasing of available P and K was significantly high when NPK fertilizer was applied to the plants but decreased at other treatments. Therefore, it can be concluded that soybean and shrub lespedeza have a significant role in changing soil nutrient status in coal mining soil through fertilizer application and biological N fixation.

Co-Inoculation of Mesorhizobium ciceri with Either Bacillus sp. or Enterobacter aerogenes on Chickpea Improves Growth and Productivity in Phosphate-Deficient Soils in Dry Areas of a Mediterranean Region

“…To estimate nitrogen fixation, we calculated the percent of nitrogen derived from air (% Ndfa). The estimated amount of fixed nitrogen is very rough because of the possibility for the influence of other soil microbes or inoculation on soil nutrient status, and thus on the intake of mineral forms of nitrogen [ 61 , 62 ]. Inoculation of chickpea with rhizobium strains MA72 or MA100 combined with M131 or P1S6 or P fertilizer resulted in a significantly higher % of nitrogen derived from air in both sites as compared to single inoculation with MA72 or MA 100 ( Table 1 ).…”

Soil bacterial communities and their associated functions for forest restoration on a limestone mine in northern Thailand

“…However, information about the composition of microbial communities that persist in mine substrates and how they might both influence and respond to mine rehabilitation, in its early stages, is still scarce. Inoculation of mine substrates with bacteria, to enhance rehabilitation, is being actively investigated, to improve plant productivity [ 17 – 19 ] post mine closure. However, few bacteria inocula can survive in mine substrates [ 18 ].…”

Effect of Fertilization and Bacterial Inoculation on Nutrient Status in Coal Mine Soil under Alder (Alnus sibirica) Plantation

“…Therefore, inoculated treatment may add only a small concentration of NO 3 − -N to the soil through nodulation because of weak nodule formation. A previous study showed increase of NO 3 − -N in the coal mine soil through bacterial inoculation and fertilization when applied to soybean and shrub lespedeza plant [13].…”

“…NH 4 + -N increased in a little amount at nonfertilized non-inoculated treatment without application of additional N, despite of using NH 4 + -N by developing plants for their growth, might be due to the mineralization of organic N present in the soil. Shin et al [13] reported increase of NH 4 + -N in the coal mine soil after 60 days of inoculation and fertilization, applied to shrub lespedeza and soybean. Cakmakci et al [14] also showed the same result in the soil of barley plant.…”