Response of soil CO2 emissions and water-carbon use efficiency of winter wheat to different straw returning methods and irrigation scenarios.

BACKGROUND: The shortage of water resources and the increase of greenhouse gas emissions from soil seriously restrict the sustainable development of agriculture. Under the premise of ensuring a stable yield of winter wheat through a reasonable irrigation scenario, identifying a suitable straw returning method will have a positive effect on agricultural carbon sequestration and emission reduction in North China Plain. RESULTS: Straw burying (SR) and straw mulching (SM) were adopted based on traditional tillage under in the winter wheat growing season of 2020-2021 and 2021-2022. Three irrigation scenarios were used for each straw returning method: no irrigation (I0), irrigation 60 mm at jointing stage (I1), and irrigation of 60 mm each at the jointing and heading stages (I2). Soil moisture, soil respiration rate, cumulative soil CO2 emissions, yield, water use efficiency (WUE) and soil CO2 emission efficiency (CEE) were mainly studied. The results showed that, compared to SM, SR improved the utilization of soil water and enhanced soil carbon sequestration. SR reduced soil respiration rate and cumulative soil CO2 emissions in two winter wheat growing seasons, and increased yield by increasing spike numbers. In addition, with an increase in the amount of irrigation, soil CO2 emissions and yield increased. Under SR-I1 treatment, WUE and CEE were the highest. SR-I1 increases crop yields at the same time as reducing soil CO2 emissions. CONCLUSION: The combination of SR and irrigation 60 mm at jointing stage is a suitable straw returning irrigation scenario, which can improve water use and reduce soil CO2 emission in NCP. © 2023 Society of Chemical Industry.

Flame Retardant Functionalization of Microcrystalline Cellulose by Phosphorylation Reaction with Phytic Acid.

The functionalization of microcrystalline cellulose (MCC) is an important strategy for broadening its application fields. In the present work, MCC was functionalized by phosphorylation reaction with phytic acid (PA) for enhanced flame retardancy. The conditions of phosphorylation reaction including PA concentration, MCC/PA weight ratio and temperature were discussed, and the thermal degradation, heat release and char-forming properties of the resulting PA modified MCC were studied by thermogravimetric analysis and pyrolysis combustion flow calorimetry. The PA modified MCC, which was prepared at 90 °C, 50%PA and 1:3 weight ratio of MCC to PA, exhibited early thermal dehydration with rapid char formation as well as low heat release capability. This work suggests a novel strategy for the phosphorylation of cellulose using PA and reveals that the PA phosphorylated MCC can act as a promising flame retardant material.

Preliminary Studies on the Application of Grape Seed Extract in the Dyeing and Functional Modification of Cotton Fabric.

Cotton has the shortcomings of having no antibacterial, antioxidant and ultraviolet (UV) protection properties, which are of great importance for health protection purposes. In the present study, grape seed extract (GSE) mainly composed of proanthocyanins (tannins) was employed to simultaneously import pale colors and the three aforementioned functions to cotton fabric. The tests on the application conditions of GSE showed that pH and GSE concentration had great impact on the color depth of cotton fabric, and the color hue of dyed fabric could be controlled in the absence of pH regulators due to the weakly acidic nature of GSE solution. The fabric dyed with 10%owf (on the weight of fabric) GSE exhibited an excellent inhibition effect towards Escherichia coli, whereas the one dyed with 20%owf GSE had high antioxidant activity of 97%. The fabric dyed with 5%owf GSE offered excellent UV protection. This study reveals that GSE can be used as a functional finishing agent for health protection in cotton textiles in addition to coloration capability.