Soil labile organic carbon fractions and soil enzyme activities after 10 years of continuous fertilization and wheat residue incorporation

Abstract

Labile organic carbon (LOC) fractions and related enzyme activities in soils are considered to be early and sensitive indicators of soil quality changes. We investigated the influences of fertilization and residue incorporation on LOC fractions, enzyme activities, and the carbon pool management index (CPMI) in a 10-year field experiment. The experiment was composed of three treatments: (1) no fertilization (control), (2) chemical fertilizer application alone (F), and (3) chemical fertilizer application combined with incorporation of wheat straw residues (F + R). Generally, the F + R treatment led to the highest concentrations of the LOC fractions. Compared to the control treatment, the F + R treatment markedly enhanced potential activities of cellulase (CL), β-glucosidase (BG), lignin peroxidase (LiP), and manganese peroxidase (MnP), but decreased laccase (LA) potential activity. Partial least squares regression analysis suggested that BG and MnP activities had a positive impact on the light-fraction organic carbon (LFOC), permanganate-oxidizable carbon (POXC), and dissolved organic carbon (DOC) fractions, whereas laccase activity had a negative correlation with those fractions. In addition, the F + R treatment significantly increased the CPMI compared to the F and control treatments. These results indicated that combining fertilization with crop residues stimulates production of LOC and could be a useful approach for maintaining sustainable production capacity in lime concretion black soils along the Huai River region of China.

Soil extracellular oxidases mediated nitrogen fertilization effects on soil organic carbon sequestration in bioenergy croplands

“…This suggested that the N fertilization effects on central tendency and spatial distribution of oxidases depended on the nature of the oxidase. However, the consistently negative correlations between oxidases (e.g., PER , PHO ) and soil organic carbon and total nitrogen and an absence of correlation with microbial biomass and some glycosidases were also identified (Table 3), which corroborated the synergistic behavior of the two oxidases involved in soil organic carbon cycling across treatments and crop species (Hassan et al, 2013; Sinsabaugh, 2010a; Zhang et al, 2020).…”

“…N fertilization can induce significant impacts on the expression, excretion, and function of soil extracellular oxidases (Matocha et al, 2004; Zhang et al, 2020). N fertilizer markedly enhanced potential activities of PER in a 10‐year field experiment in a wheat–corn rotation system (Zhang et al, 2020). However, N fertilization suppressed soil PHO activity in no‐tillage cropland systems (Matocha et al, 2004).…”

The broad impacts of corn stover and wheat straw removal for biofuel production on crop productivity, soil health and greenhouse gas emissions: A review

“…Soil organic matter and SOC are the indicators most widely studied to determine the effects of crop residue removal (Zhang et al., 2020) and are highly influenced by crop residue management (Benjamin et al., 2008; Huggins et al., 1998; Kendall et al., 2015; Zhang et al., 2020). Barber (1979) studied the effect of returning 0, 100 and 200% corn stover, and fallow for 6 years followed by 5 years of 100% corn stover return in continuous corn for 11 years on a silt loam soil in Indiana.…”

“…Although residue harvest may provide several benefits, for example, the reduction of pest and disease pressure (Wilhelm et al., 2004), concerns have arisen about potential negative impacts because they act both as sinks and sources of soil carbon that provide important ecosystem services (Su et al., 2020). Crop residues contribute to agricultural productivity by reducing soil erosion and enhancing soil physical properties (Raffa et al., 2014; Wilhelm et al., 2007) through their positive effects on soil organic carbon (SOC), nutrient availability, bulk density, water holding capacity and water infiltration (Barber, 1979; Blanco‐Canqui & Lal, 2009; Franzluebbers, 2002; Kenney, 2011; Zhang et al., 2020). However, there are still many tradeoffs and insecurities about the dependence on agronomic (e.g., residual management, tillage intensity and fertilization rate) and abiotic (e.g., soil characteristics, climate conditions) parameters.…”

Changes in soil organic carbon fractions in response to wheat straw incorporation in a subtropical paddy field in China

“…As a result, straw incorporation into the soil is essential to SOC sequestration, and thus to improving soil fertility and mitigating climate change ( Wu et al., 2019). In recent years, numerous studies have recommended straw incorporation as a key practice to manage SOC stock and its fractions in agricultural ecosystems ( Xu et al., 2011; Han et al., 2018; Wu et al., 2019; Luo et al., 2020; Zhang et al., 2020). Zhu et al.…”