scholarly journals PSXI-4 Composting management to reduce greenhouse gas and ammonia emissions from feedlot manure

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 388-388
Author(s):  
Maria A Donnay ◽  
Jennifer J Michal ◽  
GeorgiaLee J Aksdal ◽  
Brian K Lamb ◽  
Kristen A Johnson
Keyword(s):  
Greenhouse Gas ◽  
Ghg Emissions ◽  
Fine Tuning ◽  
N2o Emissions ◽  
Ammonia Emissions ◽  
Ambient Temperatures ◽  
Wind Speeds ◽  
Different Seasons ◽  
Flux Measurements ◽  
Ch4 And N2o

Abstract Management of livestock manure may recycle nutrients and decrease greenhouse gas (GHG) and ammonia (NH3) emissions. The objectives were to ascertain effects of environmental conditions and turning on methane (CH4), nitrous oxide (N2O), and NH3 emissions and if treatment with 8.5 g of dicyandiamide (DCD), a denitrification agent, altered GHG emissions. Manure and bedding were collected from feedlot pens and used to construct 3 piles (~1.9 m3 volume) each in winter (WI) and spring (SP). WI piles were turned once, and SP piles were turned twice. Methane, N2O, and NH3 emissions were collected. Methane and N2O flux measurements were collected from SP piles using a static chamber (3.7m L x 2.2m W x 0.9m H). Initial dry matter and nitrogen contents were 33.2 and 30.0% and 20.1 and 17.7 g/kg in WI and SP piles, respectively. Average ambient temperatures and wind speeds were 0.3oC and 10.7oC and 1.76 m/s and 1.97 m/s during WI and SP, respectively. Internal temperatures reached 51±3.9oC on d 4–11 and gradually decreased. Normalized CH4 averaged 2.19 mg٠s٠m-4 and N2O emissions averaged 0.84 mg٠s٠m-4, and were not different between the WI and SP piles. Turning did not affect CH4 emissions from WI piles, but were 55% greater (P < 0.05) when SP piles were turned a second time. Emissions of N2O increased 51% when WI and SP piles were turned (P < 0.05). Ammonia emissions were 83.5% greater from WI piles due to their higher initial concentrations of NH4+-N (2.21 vs. 1.11 g/kg; P < 0.05). Turning did not influence CH4 and N2O fluxes. Addition of DCD at pile formation appears to decrease N2O emissions and fluxes 3 and 10 d later. Turning management and season impacted overall CH4, N2O, and NH3 emissions. Fine-tuning manure handling and management during different seasons may effectively reduce GHG and NH3 emissions.

scholarly journals Greenhouse Gas Emissions from Cut Grasslands Renovated with Full Inversion Tillage, Shallow Tillage, and Use of a Tine Drill in Nasu, Japan

Agriculture ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 31
Author(s):  
Akinori Mori
Keyword(s):  
Greenhouse Gas ◽  
Block Design ◽  
Ghg Emissions ◽  
N2o Emissions ◽  
Weed Invasion ◽  
Significant Difference ◽  
Herbage Yield ◽  
The Difference ◽  
Ch4 And N2o ◽  
Dactylis Glomerata L

To restore the productivity of a deteriorated sward due to weed invasion, renovation (re-sowing) is necessary. However, the renovation method used can affect the sward’s greenhouse gas (GHG) emissions and herbage yield. This study compared the effects of renovation using full inversion tillage (F), shallow tillage (S), or a tine drill (T) on the GHG emissions and herbage yield of a grassland in Nasu, Japan. Two adjacent grasslands were renovated in September 2015 (year 1) and 2016 (year 2). In each year, F, S, and T plots (5 m × 20 m each) were arranged in a randomized complete block design with four replications and then orchardgrass (Dactylis glomerata L.) was seeded. All plots received 40 kg-N ha−1 for renovation and 190 kg-N ha−1 y−1 the following year. Carbon balance (i.e., the difference between C input through crop residue and C output through heterotrophic respiration), methane (CH4) and nitrous oxide (N2O) emissions, and herbage yield were measured over a period of 411 or 412 days. Cumulative N2O emissions were significantly smaller from F and S plots than from T plots, however, there was no significant difference in the sum of GHG emissions (i.e., C balance plus cumulative CH4 and N2O emissions) among F, S, and T plots. The cumulative total herbage yields of the F, S, and T plots did not differ significantly from each other. Consequently, the GHG intensity—i.e., the sum of GHG emissions per cumulative total herbage yield—was not significantly different among the F, S, and T plots.

scholarly journals Water–Air Interface Greenhouse Gas Emissions (CO2, CH4, and N2O) Emissions Were Amplified by Continuous Dams in an Urban River in Qinghai–Tibet Plateau, China

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 759 ◽  
Author(s):  
Dengxing Yang ◽  
Xufeng Mao ◽  
Xiaoyan Wei ◽  
Yaqing Tao ◽  
Zhifa Zhang ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Ghg Emissions ◽  
Tibet Plateau ◽  
Amplification Coefficient ◽  
N2o Emissions ◽  
Ghg Emission ◽  
Air Interface ◽  
Amplifying Effect ◽  
Ch4 And N2o ◽  
Qinghai Tibet Plateau

Continuous dams may lead to great variation in greenhouse gas (GHG) emissions from rivers, which contribute more uncertainty to regional carbon balance. This study is among the first to determine water–air interface GHGs (CO2, CH4, and N2O) in a river with continuous dams in plateau city. Combined static-chamber gas and meteorological chromatography were utilized to monitor the GHGs emission flux at the water–air interface within four continuous dams in the Huoshaogou River in the Qinghai–Tibet Plateau, China. A variation coefficient (VC) and amplification coefficient (AC) were designed to detect the influence of continuous dams on GHG emissions. Results indicate that (1) cascade dams presented an amplifying effect on GHGs emissions from the water-air interface. The VCs of three types of GHGs are 3.7–6.7 times higher than those of the undammed area. The ACs of three types of GHGs are 2.7–4.1 times larger than environmental factors; (2) the average GHG emission fluxes in some dams are higher than that of the first dam, indicating that an amplifying effect may have been accumulated by some continuous dams; (3) EC, pH, Twater, Tair and TDS are found to be principle influencing factors of GHG emission and light intensity, Twater, TOC (plant), TN (sediment) and TOC (sediment) are found to be associated with accumulative changes in GHG emission.

scholarly journals Optimal Coupling of Straw and Synthetic Fertilizers Incorporation on Soil Properties, Active Fe Dynamics, and Greenhouse Gas Emission in Jasminum sambac (L.) Field in Southeastern China

2019 ◽  
Vol 11 (4) ◽  
pp. 1092 ◽  
Author(s):  
Chun Wang ◽  
Qingwen Min ◽  
Abbas Abid ◽  
Jordi Sardans ◽  
Honghui Wu ◽  
...  
Keyword(s):  
Soil Properties ◽  
Greenhouse Gas ◽  
Soil Ph ◽  
Co2 Emission ◽  
Ghg Emissions ◽  
Fertilizer Treatment ◽  
N2o Emissions ◽  
Synthetic Fertilizers ◽  
Ch4 And N2o ◽  
Jasminum Sambac

In agriculture, synthetic fertilizers have played a key role in enhancing food production and keeping the world’s population adequately fed. China’s participation is essential to global efforts in reducing greenhouse gas (GHG) emissions because it is the largest producer and consumer of synthetic fertilizers. A field experiment was conducted in a Jasminum sambac (L.) field to evaluate the impact different doses of fertilizers (half, standard, and double) and their combination with straw on ecosystem (including crop plants and soil) GHG emissions. The results showed that in comparison with the control or straw treatments, the straw + standard fertilizer treatment increased the soil water content. The fertilizer treatments decreased the soil pH, but the straw and combination treatments, especially the straw + standard fertilizer treatment, had higher soil pH in comparison with the fertilizer treatment. The active soil Fe (Fe2+ and Fe3+) concentration was slightly increased in the straw + standard fertilizer treatment in comparison with the control. Moreover, fertilizer increased the CO2 emission, and we detected a positive interaction between the straw application and the double fertilization dose that increased CO2 emission, but the straw + standard fertilizer treatment decreased it. Fertilizer decreased CH4 and N2O emissions, but when straw and fertilizer treatments were applied together, this increased CH4 and N2O emissions. Overall, considering the soil properties and GHG emissions, the straw + standard fertilizer treatment was the best method to enhance soil water retention capacity, improve soil acid, and mitigate greenhouse gas emissions for sustainable management of J. sambac dry croplands.

Model analysis of energy consumption and greenhouse gas emissions of sewage sludge treatment systems with different processes and scales

2010 ◽  
Vol 61 (2) ◽  
pp. 365-373 ◽  
Author(s):  
S. Soda ◽  
Y. Iwai ◽  
K. Sei ◽  
Y. Shimod ◽  
M. Ike
Keyword(s):  
Energy Consumption ◽  
Anaerobic Digestion ◽  
Sewage Sludge ◽  
Greenhouse Gas ◽  
Ghg Emissions ◽  
N2o Emissions ◽  
Sludge Treatment ◽  
Treatment Processes ◽  
Sewage Sludge Treatment ◽  
Ch4 And N2o

An energy consumption model was developed for evaluating sewage sludge treatment plants (SSTPs) incorporating various treatment processes such as thickening, anaerobic digestion, dewatering, incineration, and melting. Based on data analyses from SSTPs in Osaka, Japan, electricity consumption intensities for thickening, anaerobic digestion, dewatering, incineration, and melting and heat consumption intensities for anaerobic digestion, incineration, and melting were expressed as functions of sludge-loading on each unit process. The model was applied for predicting the energy consumption and greenhouse gas (GHG) emissions of SSTPs using various treatment processes and power and heat generation processes using digestion gas. Results showed that SSTPs lacking incineration and melting processes but having power generation processes showed excess energy production at the high sludge-loading rate. Energy consumption of the SSTPs without incineration and melting processes were low, but their GHG emissions were high because of CH4 and N2O emissions from sludge cake at the landfill site. Incineration and melting processes consume much energy, but have lower CH4 and N2O emissions.

scholarly journals Greenhouse gas emissions from river riparian wetlands: An example from the Inner Mongolia grassland region in China

2020 ◽  
Author(s):  
Xinyu Liu ◽  
Xixi Lu ◽  
Ruihong Yu ◽  
Hao Xue ◽  
Zhen Qi ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Anthropogenic Activities ◽  
Ghg Emissions ◽  
Longitudinal Direction ◽  
Spatiotemporal Pattern ◽  
N2o Emissions ◽  
Riparian Wetlands ◽  
Riparian Wetland ◽  
Ch4 And N2o ◽  
The Impact

Abstract. Riparian wetlands play a significant role in regulating carbon and nitrogen cycles. Gradual riparian wetland drying is increasingly sensitive to global warming and contributes to climate change. In this study, we analyzed the emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from riparian wetlands in the Xilin River Basin to understand the role of these ecosystems in greenhouse gas (GHG) emissions. Moreover, the impact of the catchment hydrology and soil property variations on GHG emissions over time and space were evaluated. Our results demonstrate that riparian wetlands emit larger amounts of CO2 (335–2790 mg m−2 h−1 in August and 72–387 mg m−2 h−1 in October) than CH4 and N2O to the atmosphere due to high plant and soil respiration. The results also reveal clear seasonal variations and spatial patterns along the transects and in the longitudinal direction. N2O emissions showed a spatiotemporal pattern similar to that of CO2 emissions. Near-stream sites were the only sources of CH4 emissions, while the other sites served as sinks for these emissions. Soil moisture content and soil temperature were the essential factors controlling the GHG emissions, and abundant aboveground biomass promoted the CO2, CH4, and N2O emissions. Moreover, compared to different types of grasslands, riparian wetlands were the potential hotspots of GHG emissions in the Inner Mongolian region. Degradation of downstream wetlands has resulted in the loss of the soil carbon pool by approximately 60 %, reducing CO  emissions by approximately 35 %, and shifting the CH4 and N2O emissions from the source to the sink. Our study showed that anthropogenic activities have extensively changed the hydrological characteristics of the riparian wetlands and might accelerate carbon loss, which could further affect the GHG emissions.

scholarly journals Greenhouse gas balance of cropland conversion to bioenergy poplar short-rotation coppice

2016 ◽  
Vol 13 (1) ◽  
pp. 95-113 ◽  
Author(s):  
S. Sabbatini ◽  
N. Arriga ◽  
T. Bertolini ◽  
S. Castaldi ◽  
T. Chiti ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Arable Land ◽  
Hybrid Poplar ◽  
Ghg Emissions ◽  
Net Ecosystem Exchange ◽  
Short Rotation Coppice ◽  
Co2 Uptake ◽  
Greenhouse Gas Balance ◽  
Short Rotation ◽  
Ch4 And N2o

Abstract. The production of bioenergy in Europe is one of the strategies conceived to reduce greenhouse gas (GHG) emissions. The suitability of the land use change from a cropland (REF site) to a short-rotation coppice plantation of hybrid poplar (SRC site) was investigated by comparing the GHG budgets of these two systems over 24 months in Viterbo, Italy. This period corresponded to a single rotation of the SRC site. The REF site was a crop rotation between grassland and winter wheat, i.e. the same management of the SRC site before the conversion to short-rotation coppice. Eddy covariance measurements were carried out to quantify the net ecosystem exchange of CO2 (FCO2), whereas chambers were used to measure N2O and CH4 emissions from soil. The measurements began 2 years after the conversion of arable land to SRC so that an older poplar plantation was used to estimate the soil organic carbon (SOC) loss due to SRC establishment and to estimate SOC recovery over time. Emissions from tractors and from production and transport of agricultural inputs (FMAN) were modelled. A GHG emission offset, due to the substitution of natural gas with SRC biomass, was credited to the GHG budget of the SRC site. Emissions generated by the use of biomass (FEXP) were also considered. Suitability was finally assessed by comparing the GHG budgets of the two sites. CO2 uptake was 3512 ± 224 g CO2 m−2 at the SRC site in 2 years, and 1838 ± 107 g CO2 m−2 at the REF site. FEXP was equal to 1858 ± 240 g CO2 m−2 at the REF site, thus basically compensating for FCO2, while it was 1118 ± 521 g CO2 m−2 at the SRC site. The SRC site could offset 379.7 ± 175.1 g CO2eq m−2 from fossil fuel displacement. Soil CH4 and N2O fluxes were negligible. FMAN made up 2 and 4 % in the GHG budgets of SRC and REF sites respectively, while the SOC loss was 455 ± 524 g CO2 m−2 in 2 years. Overall, the REF site was close to neutrality from a GHG perspective (156 ± 264 g CO2eq m−2), while the SRC site was a net sink of 2202 ± 792 g CO2eq m−2. In conclusion the experiment led to a positive evaluation from a GHG viewpoint of the conversion of cropland to bioenergy SRC.

scholarly journals The nitrogen, carbon and greenhouse gas budget of a grazed, cut and fertilised temperate grassland

2016 ◽  
Author(s):  
Stephanie K. Jones ◽  
Carole Helfter ◽  
Margaret Anderson ◽  
Mhairi Coyle ◽  
Claire Campbell ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Soil Layer ◽  
The Body ◽  
Sink Strength ◽  
N2o Emissions ◽  
N Budget ◽  
N Losses ◽  
Enteric Fermentation ◽  
C And N ◽  
Ch4 And N2o

Abstract. Intensively managed grazed grasslands in temperate climates are globally important environments for the exchange of the greenhouse gases (GHGs) carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). We assessed the N and C budget of a mostly grazed, occasionally cut, and fertilized grassland in SE Scotland by measuring or modelling all relevant imports and exports to the field as well as changes in soil C and N pools over time. The N budget was dominated by import from inorganic and organic fertilisers (21.9 g N m2 yr−1) and losses from leaching (5.3 g N m2 yr−1), N2 emissions and NOx and NH3 volatilisation (6.4 g N m2 yr−1). The efficiency of N use by animal products (meat and wool) averaged 11 %. On average over nine years (2002–2010) the balance of N fluxes suggested that 7.2 ± 4.6 g N m−2 y−1 (mean ± confidence interval at p > 0.95) were stored in the soil. The largest component of the C budget was the net ecosystem exchange of CO2 (NEE), at an average uptake rate of 218 ± 155 g C m−2 y−1 over the nine years. This sink strength was offset by carbon export from the field mainly as harvest (48.9 g C m2 yr−1) and leaching (16.4 g C m2 yr−1). The other export terms, CH4 emissions from the soil, manure applications and enteric fermentation were negligible and only contributed to 0.02–4.2 % of the total C losses. Only a small fraction of C was incorporated into the body of the grazing animals. Inclusion of these C losses in the budget resulted in a C sink strength of 163 ± 140 g C m−2 y−1. On the contrary, soil stock measurements taken in May 2004 and May 2011 indicated that the grassland sequestered N in the 0–60 cm soil layer at 4.51 ± 2.64 g N m−2 y−1 and lost C at a rate of 29.08 ± 38.19 g C m−2 y-1, respectively. Potential reasons for the discrepancy between these estimates are probably an underestimation of C and N losses, especially from leaching fluxes as well as from animal respiration. The average greenhouse gas (GHG) balance of the grassland was −366 ± 601 g CO2 eq m−2 y−1 and strongly affected by CH4 and N2O emissions. The GHG sink strength of the NEE was reduced by 54 % by CH4 and N2O emissions. Enteric fermentation from the ruminating sheep proved to be an important CH4 source, exceeding the contribution of N2O to the GHG budget in some years.

Accounting for carbon exchanges in a semiarid oak savanna (dehesa).

2021 ◽  
Author(s):  
Ana Andreu ◽  
Elisabet Carpintero ◽  
Pedro Gómez-Giraldez ◽  
Maria P. González-Dugo
Keyword(s):  
Ghg Emissions ◽  
Negative Evaluation ◽  
System Structure ◽  
Economic Production ◽  
Tree Layer ◽  
Agrosilvopastoral System ◽  
Flux Measurements ◽  
Scattered Trees ◽  
Extensive Farming ◽  
Ch4 And N2o

<p>Semiarid oak savannas (grasslands with scattered trees), partially covered, subject to regular droughts, grazing, and high levels of solar radiation, are nonetheless, typically carbon sinks regarding CO2. However, dehesas are a productive system, a trait shared with other savannas, and they are shaped by their uses for economic production. One of its multiple uses, livestock extensive farming, key to its economic profitability and to the preservation of the agrosilvopastoral system structure, modifies the Greenhouse gas (GHG) balance by adding a significant amount of CH4 and N2O into the cycle. Recent reports and publications have evaluated and compared different types of livestock management within the context of climate change. GHG emissions, extensive use of the soil resource, or the introduction of nitrogen into the system, are some of the generated effects that cause a negative evaluation of extensive farming. Nevertheless, the importance of this sector, given its extension and impact on production and rural development, demands a more rigorous evaluation. It is necessary to precisely account for the fluxes in their totality (including the CO2 sink effect) and the relationships between them. Currently, there are few studies that determine the GHG balance of dehesas, and they are mainly centred on CO2 fluxes without integrating the influence of livestock, or in meadows without a tree layer (which changes the CO2 balance). The net global warming potential of dehesas is unknown, given that very few direct and long-term flux measurements have been taken on them. In this work, CO2 and H2O fluxes from an eddy covariance tower located in an Andalusian dehesa were processed (standard corrections), filtered and homogenized, including filling gaps using artificial neural networks. We calculated the annual CO2 budget since 2015, to assess the sink/source nature of the area. In a modeling exercise to be able to close the carbon cycle, we estimated CH4 and N2O depending on the number of livestock present in the area by season/year, evaluating the tipping point.</p>

scholarly journals The European land and inland water CO<sub>2</sub>, CO, CH<sub>4</sub> and N<sub>2</sub>O balance between 2001 and 2005

2012 ◽  
Vol 9 (8) ◽  
pp. 3357-3380 ◽  
Author(s):  
S. Luyssaert ◽  
G. Abril ◽  
R. Andres ◽  
D. Bastviken ◽  
V. Bellassen ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Aquatic Ecosystems ◽  
Terrestrial Ecosystems ◽  
C Sequestration ◽  
Sink Strength ◽  
Terrestrial Carbon Sequestration ◽  
Net Uptake ◽  
Flux Measurements ◽  
Ch4 And N2o ◽  
Constraint Approach

Abstract. Globally, terrestrial ecosystems have absorbed about 30% of anthropogenic greenhouse gas emissions over the period 2000–2007 and inter-hemispheric gradients indicate that a significant fraction of terrestrial carbon sequestration must be north of the Equator. We present a compilation of the CO2, CO, CH4 and N2O balances of Europe following a dual constraint approach in which (1) a land-based balance derived mainly from ecosystem carbon inventories and (2) a land-based balance derived from flux measurements are compared to (3) the atmospheric data-based balance derived from inversions constrained by measurements of atmospheric GHG (greenhouse gas) concentrations. Good agreement between the GHG balances based on fluxes (1294 ± 545 Tg C in CO2-eq yr−1), inventories (1299 ± 200 Tg C in CO2-eq yr−1) and inversions (1210 ± 405 Tg C in CO2-eq yr−1) increases our confidence that the processes underlying the European GHG budget are well understood and reasonably sampled. However, the uncertainty remains large and largely lacks formal estimates. Given that European net land to atmosphere exchanges are determined by a few dominant fluxes, the uncertainty of these key components needs to be formally estimated before efforts could be made to reduce the overall uncertainty. The net land-to-atmosphere flux is a net source for CO2, CO, CH4 and N2O, because the anthropogenic emissions by far exceed the biogenic sink strength. The dual-constraint approach confirmed that the European biogenic sink removes as much as 205 ± 72 Tg C yr−1 from fossil fuel burning from the atmosphere. However, This C is being sequestered in both terrestrial and inland aquatic ecosystems. If the C-cost for ecosystem management is taken into account, the net uptake of ecosystems is estimated to decrease by 45% but still indicates substantial C-sequestration. However, when the balance is extended from CO2 towards the main GHGs, C-uptake by terrestrial and aquatic ecosystems is offset by emissions of non-CO2 GHGs. As such, the European ecosystems are unlikely to contribute to mitigating the effects of climate change.

scholarly journals Quantifying the Effects of Biochar Application on Greenhouse Gas Emissions from Agricultural Soils: A Global Meta-Analysis

2020 ◽  
Vol 12 (8) ◽  
pp. 3436 ◽  
Author(s):  
Qi Zhang ◽  
Jing Xiao ◽  
Jianhui Xue ◽  
Lang Zhang
Keyword(s):  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Crop Yield ◽  
Radiative Forcing ◽  
Specific Activity ◽  
C:N Ratio ◽  
Ghg Emissions ◽  
N2o Emissions ◽  
Response Ratio ◽  
Gas Emissions

Agricultural disturbance has significantly boosted soil greenhouse gas (GHG) emissions such as methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O). Biochar application is a potential option for regulating soil GHG emissions. However, the effects of biochar application on soil GHG emissions are variable among different environmental conditions. In this study, a dataset based on 129 published papers was used to quantify the effect sizes of biochar application on soil GHG emissions. Overall, biochar application significantly increased soil CH4 and CO2 emissions by an average of 15% and 16% but decreased soil N2O emissions by an average of 38%. The response ratio of biochar applications on soil GHG emissions was significantly different under various management strategies, biochar characteristics, and soil properties. The relative influence of biochar characteristics differed among soil GHG emissions, with the overall contribution of biochar characteristics to soil GHG emissions ranging from 29% (N2O) to 71% (CO2). Soil pH, the biochar C:N ratio, and the biochar application rate were the most influential variables on soil CH4, CO2, and N2O emissions, respectively. With biochar application, global warming potential (impact of the emission of different greenhouse gases on their radiative forcing by agricultural practices) and the intensity of greenhouse gas emissions (emission rate of a given pollutant relative to the intensity of a specific activity) significantly decreased, and crop yield greatly increased, with an average response ratio of 23%, 41%, and 21%, respectively. Our findings provide a scientific basis for reducing soil GHG emissions and increasing crop yield through biochar application.

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