|WANG, JUN - Northwest University|
|FU, XIN - Northwest University|
|ZHAO, FAZHU - Northwest University|
Submitted to: Soil Science Society of America Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/3/2018
Publication Date: 3/22/2018
Citation: Wang, J., Fu, X., Zhao, F., Sainju, U.M. 2018. Response of soil carbon fractions and dryland maize yield to mulching. Soil Science Society of America Journal. 82(2):371–381. https://doi.org/10.2136/sssaj2017.11.0397 .
Interpretive Summary: Straw mulching enhances soil health and maize yield. Mulching is a popular way to conserve soil water and sustaining dryland crop yield in south Asia, but its effect on soil health and quality is not well known. ARS scientist in Sidney, MT collaborated with scientists from Northwest University, Xian, China to study the five-year effect of straw and plastic film mulching on soil labile and nonlabile carbon fractions and dryland maize yield in the Loess Plateau of China. They found that plastic film mulching increased maize yield, but reduced soil carbon fractions compared with straw and no mulching. In contrast, straw mulching increased soil carbon fractions by 35% and maize yield by 33% compared with no mulching. They concluded that straw mulching can enhance carbon sequestration and soil health by increasing soil microbial biomass and activity as well as maize yield compared with no mulching.
Technical Abstract: Stimulation of root growth from mulching may enhance soil C fractions under maize (Zea mays L.). We studied the 5-yr straw (SM) and plastic film (PM) mulching effect on soil C fractions and maize yield compared with no mulching (CK) in the Loess Plateau of China. Soil samples collected from 0- to 10- and 10- to 20-cm depths after maize harvest in the fall, 2011 to 2015, were analyzed for soil organic C (SOC), particulate organic C (POC), potential C mineralization (PCM), and microbial biomass C (MBC). At both depths, all C fractions were 7 to 35% greater with SM than PM and CK. At 0 to 20 cm, SOC increased at 0.87 Mg C ha-1 yr-1 with PM and POC increased at 0.18 and 0.54 Mg C ha-1 yr-1 with SM and PM, respectively, from 2011 to 2015. Maize grain yield and aboveground biomass were 5 to 33% greater with PM and SM than CK. The PCM and MBC at all depths were negatively correlated with maize grain yield, but SOC and POC at 10 to 20 cm were positively correlated with estimated maize root residue returned to the soil. Plastic film mulching increased maize yield, but reduced soil C fractions compared with straw mulching. Because of favorable effect on soil C fractions and maize yield, straw mulching can enhance soil C sequestration and microbial biomass and activity due to increased straw and root C inputs as well as maize yield compared with no mulching under dryland cropping systems.