Single midseason drainage events decrease global warming potential without sacrificing grain yield in flooded rice systems

Replacing bare fallow by rotation with winter cereal crops such as winter wheat and oil rape have been used to improve annual productivity in paddy cropping system in central China. However, the effects of rotation on light and heat resources utilization and greenhouse gases have yet to be measured. A two-year field experiment was conducted to compare solar radiation and heat use efficiencies, methane (CH4) and nitrous oxide (N2O) emissions and global warming potential (GWP) of two winter rotations: rice-wheat and rice-rape taking rice-fallow as a check. The results of this study showed that rice-wheat had the highest annual grain yield (two-year means were 16.2 t ha-1) and annual above ground biomass (32.9 t ha-1) followed by ricerape and by rice-fallow. No significant effect was observed for winter rotation on the performance of rice grain yield and growth, in spite of a large quantity of straw returning by winter crops. Solar radiation and heat resources utilization and their production efficiency were improved in the winter season by rotation with winter crops. Rice-wheat and rice-rape also increased light and heat resources utilization efficiency from the annual perspective. Compared with rice-fallow, CH4 flux in the rice season among the two studying years was increased by 42.0% by rice-wheat but was decreased by 35.6% by rice-rape. For the annual level, CH4 flux was promoted by 40.9% by rice-wheat and declined by 35.5% by rice-rape. For the rice season the N2O seasonal flux was increased by 54.2 and by 8.3% in rice-wheat and rice-rape plots, respectively. The values for GWP and for yield-scaled GWP were highest in rice-wheat and lowest in rice-rape system. In conclusion, rice-rape system could be a better choice to increase solar radiation and heat resources utilization and mitigate greenhouse gases emission. © 2021 Friends Science Publishers

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Variation in Soil Properties Regulate Greenhouse Gas Fluxes and Global Warming Potential in Three Land Use Types on Tropical Peat

Atmosphere ◽

10.3390/atmos9120465 ◽

2018 ◽

Vol 9 (12) ◽

pp. 465 ◽

Cited By ~ 7

Author(s):

Kiwamu Ishikura ◽

Untung Darung ◽

Takashi Inoue ◽

Ryusuke Hatano

Keyword(s):

Global Warming ◽

Soil Moisture ◽

Groundwater Level ◽

Global Warming Potential ◽

C:N Ratio ◽

Co2 Flux ◽

Nitrate Content ◽

N2o Flux ◽

Ch4 Flux ◽

In The Beginning

This study investigated spatial factors controlling CO2, CH4, and N2O fluxes and compared global warming potential (GWP) among undrained forest (UDF), drained forest (DF), and drained burned land (DBL) on tropical peatland in Central Kalimantan, Indonesia. Sampling was performed once within two weeks in the beginning of dry season. CO2 flux was significantly promoted by lowering soil moisture and pH. The result suggests that oxidative peat decomposition was enhanced in drier position, and the decomposition acidify the peat soils. CH4 flux was significantly promoted by a rise in groundwater level, suggesting that methanogenesis was enhanced under anaerobic condition. N2O flux was promoted by increasing soil nitrate content in DF, suggesting that denitrification was promoted by substrate availability. On the other hand, N2O flux was promoted by lower soil C:N ratio and higher soil pH in DBL and UDF. CO2 flux was the highest in DF (241 mg C m−2 h−1) and was the lowest in DBL (94 mg C m−2 h−1), whereas CH4 flux was the highest in DBL (0.91 mg C m−2 h−1) and was the lowest in DF (0.01 mg C m−2 h−1), respectively. N2O flux was not significantly different among land uses. CO2 flux relatively contributed to 91–100% of GWP. In conclusion, it is necessary to decrease CO2 flux to mitigate GWP through a rise in groundwater level and soil moisture in the region.

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Simulation of Mixing Synthetic with hydrocarbons Refrigerant to Reduce the Value of Global Warming Potential with Refprop Software

Journal of Physics Conference Series ◽

10.1088/1742-6596/1764/1/012158 ◽

2021 ◽

Vol 1764 (1) ◽

pp. 012158

Author(s):

Widodo ◽

TK Berkah Fajar ◽

MSK Tony Suryo ◽

SH Winoto

Keyword(s):

Global Warming ◽

Global Warming Potential

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Integrated assessment of system of rice intensification vs. conventional method of transplanting for economic benefit, energy efficiency and lower global warming potential in India

Agroecology and Sustainable Food Systems ◽

10.1080/21683565.2020.1868648 ◽

2021 ◽

pp. 1-22

Author(s):

B. Nirmala ◽

M. D. Tuti ◽

R. Mahender Kumar ◽

Amtul Waris ◽

P. Muthuraman ◽

...

Keyword(s):

Energy Efficiency ◽

Global Warming ◽

Conventional Method ◽

Global Warming Potential ◽

Integrated Assessment ◽

Economic Benefit ◽

System Of Rice Intensification ◽

Rice Intensification

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Influence of technical and electrical equipment in life cycle assessments of buildings: case of a laboratory and research building

The International Journal of Life Cycle Assessment ◽

10.1007/s11367-021-01919-9 ◽

2021 ◽

Author(s):

E. Hoxha ◽

D. Maierhofer ◽

M.R.M Saade ◽

A. Passer

Keyword(s):

Global Warming ◽

Environmental Impacts ◽

Global Warming Potential ◽

Electrical Equipment ◽

Primary Energy ◽

Electronic Equipment ◽

Detailed Result ◽

Detailed Calculation ◽

System Boundary ◽

Operational Energy

Abstract Purpose A detailed assessment of the environmental impacts of the building requires a substantial amount of data that is time- and effort-consuming. However, limitation of the system boundary to certain materials and components can provide misleading impact calculation. In order to calculate the error gap between detailed and simplified assessments, the purpose of this article is to present a detailed calculation of the environmental impacts of the building by including in the system boundary, the technical, and electrical equipment. Method To that end, the environmental impacts of a laboratory and research building situated in Graz-Austria are assessed following the EN-15978 norm. Within the system boundaries of the study, the material and components of building fabric, technical, and electronic equipment for the building lifecycle stages of production, construction, replacement, operational energy and water, and end-of-life are considered. The input data regarding the quantity of materials is collected from the design and tendering documents, invoices, and from discussion with the head of the building’s construction site. Primary energy and global warming potential indicators are calculated on the basis of a functional unit of 1 m2 of energy reference area (ERA) per year, considering a reference building service life of 50 years. Results and discussion The primary energy indicator of the building is equal to 1698 MJ/m2ERA/year. The embodied impacts are found to be responsible for 28% of which 6.4% is due to technical and electronic equipment. Furthermore, the embodied impacts for the global warming potential, equal to 28.3 kg CO2e/m2ERA/year, are responsible for 73%. Together, technical and electrical equipment are the largest responsible aspects, accounting for 38% of the total impacts. Simplified and detailed result comparisons show a gap of 29% and 7.7% for global warming and primary energy indicators. These differences were from the embodied impacts and largely from the exclusion of electrical equipment from the study’s system boundary. Conclusions Technical and electrical equipment present a significant contribution to the overall environmental impacts of the building. Worthy of inclusion in the system boundary of the study, the environmental impacts of technical and electrical equipment must be calculated in detail or considered with a reliable ratio in the early design phase of the project. Further research is necessary to address the detailed impact calculation of the equipment and notably the minimization of their impacts.

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