Effect of household land management on cropland topsoil organic carbon storage at plot scale in a red earth soil area of South China

Abstract

SUMMARYAn inventory of topsoil soil organic carbon (SOC) content in household farms was performed in a village from a red earth region in Jiangxi Province, China in 2003. In this region, the farmland managed by each household is fragmented, consisting of several plots of land that are not necessarily adjacent to each other. A statistical analysis of SOC variation with land use and household management type, and with crop management practices was conducted. Plot size ranged from 0·007 to 0·630 ha with a mean of 0·1 ha, and SOC content ranged from 1·72 to 25·2 g/kg, varying widely with a variety of land management and agricultural practices, arising from individual household behaviours. The mean SOC content in plot size <0·1 ha was 20% lower than in plot size ⩾0·1 ha. SOC of dry crop plots was 70% lower than that in rice paddies, and SOC of plots contracted from the village was almost double that of plots leased from other householders. Moreover, a 30% increase in SOC was observed with green manure cultivation, and a 55% increase under triple cropping. The difference in SOC levels between the least and most favourable cases of household land management and agricultural practice was up to 150%. The results suggest that policies targeted at crop management alone may not deliver the expected SOC benefits if household land management is also not improved.

A comparative study on carbon footprint of rice production between household and aggregated farms from Jiangxi, China

“…Similarly, Tan et al (2008) examined the impact of land fragmentation on the production costs of rice farm in Jiangxi and found an increase in farm size decreased the total production cost. Feng et al (2011) reported that topsoil SOC storage could be higher over 30 % in larger sized farms (>0.7 ha, 10 Chinese mu) than in smaller ones (<0.7 ha) from survey work in a similar region as this study. In a comparable study using questionnaire data, Sefeedpari et al (2013) reported that farms less than 1 ha had a higher total energy input by 17, 21, and 34 % respectively than those of 1-4, 4-10, and >10 ha for rain-fed wheat production from central Iran.…”

“…However, big scale farms in China with intensive management have been developed in land consolidation programs. Constraints on land resource availability due to fragmented croplands and small household management systems impact on crop production (Tan et al 2008;Feng et al 2011). Schäfer and Blanke (2012) indicated that there were significant differences of CF among the different scales of farm business for pumpkin production.…”

Carbon footprint of China's livestock system – a case study of farm survey in Sichuan province, China

“…This phenomenon was also observed in crop production. For example, Feng et al (2011) reported that topsoil SOC storage could be over 30% higher in larger sized farms (>0.7 ha) than in smaller ones (<0.7 ha) from a survey work in a region of China. Sefeedpari et al (2013) also presented that farms less than 1 ha had a higher total energy input by 17, 21 and 34% respectively than those of 1e4 ha, 4e10 ha and >10 ha for rain-fed wheat production from central Iran.…”

Perspectives on studies on soil carbon stocks and the carbon sequestration potential of China

“…Their potential impact on SOC had again received much attention for the globe other than China [52]. A pilot study of soil quality and household farming was conducted in a rural area of Jiangxi Province where the local people had been traditionally living on their land [53]. In this case, the topsoil SOC varied widely from 1.7 to 25.2 g kg 1 , depending on the size of total cropland area and the land tenure status.…”

“…In addition, land management systems for croplands tend to have an impact on their technological potential. For example, a recent study has shown that significantly higher, by up to one third, SOC sequestration rates in croplands with a bigger plot size and non-leased croplands than those in smaller and sub-contracted or leasing arrangements [53]. Evidently, improving the land tenure system and developing scaled cropland management would be one of the major approaches to working towards enhancing SOC sequestration in China's croplands.…”