An antagonistic effect of elevated CO2 and warming on soil N2O emissions related to nitrifier and denitrifier communities in a Chinese wheat field

Environmental Microbiology

et al. 2022

Self Cite

Plant root‐associated microbial communities profoundly affect plant nutrition and productivity. Although elevated atmospheric CO2 and warming affect above‐ and belowground plant processes, it remains unclear how root‐associated microbial communities respond to elevated CO2 and warming. In this study, an open‐air field experiment was conducted to assay the interactive effects of elevated CO2 (500 ppm) and warming (+2°C) on the root‐associated microbiota and soil enzyme activities in a rice–wheat rotation ecosystem. The results revealed that elevated CO2 significantly increased rhizosphere soil organic carbon (SOC) and total nitrogen contents. In addition, glucosidase, β‐xylosidase, and phosphatase activities significantly increased. The richness and Shannon diversity indices were significantly higher in rhizosphere soil than in root endosphere. Elevated CO2 and warming significantly impacted the rhizosphere soil microbiota and altered their composition by changing the relative abundance of some specific groups. Soil pH, SOC, and available potassium content significantly altered the dominant bacterial phyla in the rhizosphere. SOC affected root endophytic bacterial phyla. Bacterial and fungal genera were significantly correlated with soil variables in the rhizosphere than in the root endosphere. These results indicate that microbial communities in the rhizosphere are more sensitive to elevated CO2 and warming than those in the root endosphere.

Section: Experimental Designmentioning

confidence: 72%

Effects of elevated CO₂ and warming on the root‐associated microbiota in an agricultural ecosystem

Gao

Mao

Environmental Microbiology

et al. 2022

Self Cite

“…After the heading stage, a compound fertilizer of 375 kg ha -1 NPK and 150 kg ha -1 urea was applied for top-dressing. The experimental eld managements, including weed control, insecticide and fungicide application, were consistent in all the ring plots (Liu et al 2017;Liu et al 2022).…”

Section: Experimental Designmentioning

confidence: 78%

Long-term elevated atmospheric CO2 and warming affect the root-associated microbiomes of rice and wheat

Gao

Mao

et al. 2022

Preprint

Self Cite

Background: Plant root-associated microbial communities profoundly affect plant nutrition and productivity. Although elevated atmospheric CO2 and warming have been suggested to affect above- and belowground plant processes, it remains unclear how root-associated microbial communities respond to elevated CO2 and warming, particularly in agroecosystems. Result: Here, an open-air field experiment was conducted to assay the interactive effects of elevated CO2 (500 ppm) and warming (+2℃) on the root-associated microbiomes and soil enzyme activities in a rice-wheat rotation ecosystem. The results revealed a significant increase in rhizosphere soil organic carbon (SOC) and total nitrogen contents from elevated CO2. In addition, glucosidase, β-xylosidase, and phosphatase activities increased significantly. The rhizosphere soils of rice and wheat had significantly higher richness and Shannon diversity indices than the root endosphere. Besides, the bacterial and fungal compositions were significantly altered between the two compartments. Elevated CO2 and warming had more impact on the rhizosphere soil microbiomes and altered their composition by changing the relative abundance of some particular groups. Soil pH, SOC, and available potassium significantly altered the dominant bacterial phyla in the rhizosphere. In contrast, the SOC affected the root endophytic bacterial phyla. Moreover, more bacterial and fungal genera were significantly correlated with soil variables in the rhizosphere than in the root endosphere. Elevated CO2 had significant effects on the numbers of bacterial genera, including Burkholderia, Rhizobium, Pantoea, Gemmatimonas, Dongia, Defluviicoccus, Anaeromyxobacter, and Povalibacter, that significantly correlated with soil variables. Conclusion: These results indicate that the microbial communities in the rhizosphere of rice and wheat are more sensitive to elevated CO2 and warming than the root endophytic microbiomes. Moreover, the dissimilarity of root-associated bacteria is greater than that of the fungal community in the root endosphere.

“…We found significant exponential correlations between soil N 2 O and CO 2 concentrations ( Figure 3 ), and cumulative N 2 O emissions were significantly correlated with soil CO 2 concentrations ( Figure 6 ). As previous studies mentioned, elevated atmospheric CO 2 increased soil nitrification rate and shifted ammonia-oxidizing community abundance and structure [ 35 , 36 , 37 ]. Elevated CO 2 could both significantly shift amoA - AOB and amoA - AOA communities, and amoA - AOB was more sensitive to the rising CO 2 concentration [ 35 ].…”

Section: Discussionmentioning

confidence: 94%

Black Plastic Film Mulching Increases Soil Nitrous Oxide Emissions in Arid Potato Fields

Zhao

Wang

et al. 2022

IJERPH

Black plastic film mulching is a common practice for potato production in the arid area of Northwest China. Many studies have reported the significant positive effect of black plastic film mulch on potato harvest, while the effect of black plastic film mulch treatment on soil nitrous oxide (N2O) emissions is still unclear. As a consequence, this study aimed to examine the effect of black plastic film mulch treatment on N2O emission from arid upland potato fields. With the static chamber-gas chromatography method, soil N2O emissions were measured. The results showed that black plastic film mulching treatment significantly increased cumulative soil N2O emissions by 21–26% compared with non-mulched treatment. Cumulative N2O emission positively correlated with soil temperature, soil moisture, soil CO2 concentration, and amoA-AOB abundance. This study indicated that black plastic film mulching, mainly through increasing soil temperature and soil moisture, increasing soil carbon dioxide (CO2) concentration, and promoting the abundance of nitrification-related functional gene of amoA-AOB, regulated N2O emissions. This study also highlighted that the specific soil environment under black plastic film mulch is conducive to N2O emissions and lay the foundation for settling the contradiction between food production and greenhouse gas mitigation in upland soils. The negative effects of black plastic film mulching on the environment should be considered in future applications in food production.