Soil Organic Carbon Molecular Properties: Effects of Time Since Reclamation in a Minesoil Chronosequence

Abstract

Studies on molecular characterization of soil organic carbon (SOC), although critical to understanding SOC dynamics, are relatively scarce for reclaimed minesoils. The aim of this study was to assess the effects of time since reclamation on SOC molecular properties in a reclaimed minesoil chronosequence using different spectroscopic indices. The chronosequence consisted of four minesoils, with similar soil-forming conditions, reclaimed to pasture ecosystem, and distinguished only by time since reclamation varying from 1 to 22 years. Results indicated that the SOC molecules in the older minesoils were comprised of highly humified polyaromatic and polycondensed species with higher proportions of O-containing and N-containing functional groups. In each minesoil, resistant and labile SOC fractions were identified. The resistant SOC fraction constituted >20 and <10 per cent of total SOC (g kg À1 ) in the oldest and youngest minesoil, respectively. Among the spectroscopic indices, the e 285 ultraviolet-visible index, diagnostic of aromatic C, was the most efficient in identifying the intrasite short-term (1-year) changes in SOC molecular properties. Strong positive relationships found between different spectroscopic indices and total SOC (g kg À1 ), with consistently higher r 2 values observed in older minesoils, indicated that SOC molecular characteristics played a key role in overall SOC dynamics, becoming more influential with increasing time since reclamation. In addition, significant relationships between the spectroscopic indices and different soil quality parameters indicated that SOC molecular properties influenced soil quality as well. Overall, the results indicated that SOC molecular properties were useful indicators of both SOC dynamics and soil quality in this minesoil chronosequence.

Assessment of environmental soil quality around Sonepur Bazari mine of Raniganj coalfield, India

“…Soil quality indices are useful to differentiate between the degraded status of soils (Morugán-Coronado et al, 2013). Though there are a few studies on the assessment of soil parameters on coal mine soil (Mukhopadhyay and Maiti, 2014;Tizado and Núñez-Pérez, 2014;Pallavicini et al, 2015;Haigh et al, 2015;Chaudhuri et al, 2015), integrated estimation of soil quality is limited.…”

Soil biochemical properties in brown and gray mine soils with and without hydroseeding

“…In this manner, the success of reclamation practices and the return of ecosystem services could be evaluated. Other studies have examined these dynamic biochemical properties over time and demonstrated the development and evolution of microbial populations and diversity, which were used to indicate reclamation success on a site (Akala and Lal, 2001;Anderson et al, 2008;Chaudhuri et al, 2015;Insam and Domsch, 1988). According to a chronosequence study of reclaimed sites in West Virginia by Stephens et al (2001), reclaimed mines saw a pulse in microbial activity and biomass in the first 10 years after reclamation, followed by a steady de-cline during the following years.…”

“…However, their biochemical activities can be slow to re-establish (Chodak, 2009) and may take several decades to reach stable conditions normally found in native soils (Chatterjee et al, 2009;Insam and Domsch, 1988). Soil carbon amendments stimulate microbiological activity (Bendfeldt et al, 2001;Elkins et al, 1984;Lindemann et al, 1984), as can the establishment of herbaceous plants using the additions of fertilizers and lime (Chaudhuri et al, 2015). However, as easily decomposable organic matter is rapidly consumed, an overall decline of microbial activity results if no further additions of external nutrients and organic matter are applied because a reservoir of soil organic matter is lacking in newly created mine soils (Stephens et al, 2001;Stroo and Jencks, 1982).…”

Effects of topsoil treatments on afforestation in a dry Mediterranean climate (southern Spain)

“…One way to improve soil conditions is to apply organic amendments to the soil. Numerous studies have assessed the use of organic amendments for vegetation establishment and soil fertility, including agricultural soils (Ojeda et al, 2003;Jordán et al, 2010;Jiménez et al, 2013;Tejada and Gonzalez, 2013), eroded soils (Cohen-Fernández and Naeth, 2013;Prats et al, 2016;Donn et al, 2014;Hosseini Bai et al, 2014;Cerdà et al, 2016;, post-mining soils (Eldridge et al, 2012;Benigno et al, 2013;Muñoz-Rojas et al, 2016b), and afforested soils under Mediterranean conditions (Hueso-González et al, 2014Sadeghi et al, 2015).…”

“…SOC can be a limiting factor for plant establishment in semiarid lands with degraded soils (Almendros et al, 2010;Hueso-González et al, 2014). Under these conditions, larger rates of plant survival can be expected when soils are amended with external sources of organic matter (Jordán et al, , 2011Chaudhuri et al, 2015;Shazana et al, 2013;Srinivasarao et al, 2013). In fact, the addition of soil organic matter by means of crop residues such as mulch, sewage sludge, or animal manure can enhance vegetation growth and cover (Montgomery et al, 2007;Ferreras et al, 2006;Franco-Otero et al, 2011;González-Ubierna et al, 2012).…”