Influence of climate on soil organic carbon in Chinese paddy soils

Abstract

Soil organic carbon (SOC) is a major component of the global carbon cycle and has a potentially large impact on the greenhouse effect. Paddy soils are important agricultural soils worldwide, especially in Asia. Thus, a better understanding of the relationship between SOC of paddy soils and climate variables is crucial to a robust understanding of the potential effect of climate change on the global carbon cycle. A soil profile data set (n = 1490) from the Second National Soil Survey of China conducted from 1979 to 1994 was used to explore the relationships of SOC density with mean annual temperature (MAT) and mean annual precipitation (MAP) in six soil regions and eight paddy soil subgroups. Results showed that SOC density of paddy soils was negatively correlated with MAT and positively correlated with MAP (P < 0.01). The relationships of SOC density with MAT and MAP were weak and varied among the six soil regions and eight paddy soil subgroups. A preliminary assessment of the response of SOC in Chinese paddy soils to climate indicated that climate could lead to a 13% SOC loss from paddy soils. Compared to other soil regions, paddy soils in Northern China will potentially more sensitive to climate change over the next several decades. Paddy soils in Middle and Lower Yangtze River Basin could be a potential carbon sink. Reducing the climate impact on paddy soil SOC will mitigate the positive feedback loop between SOC release and global climate change.

Soil Organic Carbon and Total Nitrogen Stocks and Interactions with Soil Metal Oxides in Different Climatic Zones

“…In our study, climate factors (MAT, MAP, and MACT) were found to have a significant effect on SOC and STN storage due to RDA (Figure 2), and we also found that temperature had a greater effect on SOC and STN content than rainfall (Table 1). These results were similar to those from previous studies by Alvarez and Lavado and Wang et al, which demonstrated that climatic factors (especially temperature and precipitation) play an important role in regulating SOC storage because climate determines plant species, production methods, and decomposition processes of deadfall [46][47][48]. Prior research has shown that soil C/N is a key indicator of soil nitrogen mineralization capacity [49].…”

“…In summary, MAT and MAP may be the dominant factors in determining the spatial distribution of SOC and STN storage. Similarly to studies by Assefa et al, [58], Wang et al [47,48], and Njeru et al [59], SOC was highly significantly correlated with STN storages. In addition, SOC and STN contents were significantly and negatively correlated with soil depth in all climatic zones, and both SOC and STN contents were significantly phenocopied (Table 2 and Figure A1).…”

Impact of suburban cropland intensification and afforestation on microbial biodiversity and C sequestration in paddy soils

“…Moreover, the succession of bacterial and fungal community control over soil C storage in the farming system also differences in opinions (Shen et al, 2021; Tardy et al, 2015). Wang et al (2017) revealed the contribution of fungal decomposition to forming soil organic matter. Tardy et al (2015) showed land use intensity from optimal management to moderate land use intensity may promote both bacterial and fungal diversity, while some research resulting from bacteria can affect the composition of fungi through negative correlation (Hicks et al, 2019; Silva‐Sánchez et al, 2019).…”

“…Paddy soils (Stagnic Anthrosols) account for 23% of the world's total irrigated lands (Gong, 1999; Pang et al, 2004). The C sequestration potential of paddy soils is considerable (Chen et al, 2021; Wang et al, 2017) due to its unique water management requirements and topsoil organic C accumulation (Wissing et al, 2013; Zhang et al, 2021). Our previous researches explored chemical fractions of paddy soil's organic C and physical protection of organic C vary across suburban agricultural land uses (Guo et al, 2020; Luo et al, 2019).…”

Spatio-temporal Changes and Associated Uncertainties of CENTURY-modelled SOC for Chinese Upland Soils, 1980–2010

“…Concerning the significance of SOC for food production, soil and water quality enhancement, and greenhouse gas emissions mitigation (Qin et al, 2016;Wang et al, 2017;Zhao et al, 2018), many previous studies have examined the size and change in SOC of Chinese uplands through the meta-analysis of SOC data collected from published literature (Xie et al, 2007;Pan et al, 2010;Sun et al, 2010). However, the meta-analysis method has some inherent limitations, especially in representing the long-term time series of SOC dynamics and the impacts of heterogeneous soil conditions and management practices on SOC dynamics (Sun et al, 2010;Yu et al, 2012).…”