scholarly journals New estimates of direct N<sub>2</sub>O emissions from Chinese croplands from 1980 to 2007 using localized emission factors

2011 ◽  
Vol 8 (10) ◽  
pp. 3011-3024 ◽  
Author(s):  
B. Gao ◽  
X. T. Ju ◽  
Q. Zhang ◽  
P. Christie ◽  
F. S. Zhang
Keyword(s):  
Agricultural Land ◽  
Original Data ◽  
Emission Factors ◽  
Paddy Fields ◽  
Annual Rate ◽  
Anthropogenic Sources ◽  
Cube Root ◽  
N2o Emissions ◽  
The North ◽  
Rate Of Increase

Abstract. Nitrous oxide (N2O) is a long-lived greenhouse gas with a large radiation intensity and it is emitted mainly from agricultural land. Accurate estimates of total direct N2O emissions from croplands on a country scale are important for global budgets of anthropogenic sources of N2O emissions and for the development of effective mitigation strategies. The objectives of this study were to re-estimate direct N2O emissions using localized emission factors and a database of measurements from Chinese croplands. We obtained N2O emission factors for paddy fields (0.41 ± 0.04%) and uplands (1.05 ± 0.02%) from a normalization process through cube root transformation of the original data. After comparing the results of normalization from the original values, Logarithmic and cube root transformations were used because the frequency of the original data was not normally distributed. Direct N2O emissions from Chinese croplands from 1980 to 2007 were estimated using IPCC (2006) guidelines combined with separate localized emission factors for paddy fields and upland areas. Direct N2O emissions from paddy fields showed little change, increasing by 10.5% with an annual rate of increase of 0.4% from 32.3 Gg N2O-N in 1980 to 35.7 Gg N2O-N in 2007. In contrast, emissions from uplands changed dramatically, increasing by 308% with an annual rate of 11% from 68.0 Gg N2O-N in 1980 to 278 Gg N2O-N in 2007. Total direct N2O emissions from Chinese croplands increased by 213% with an annual rate of 7.6% from 100 Gg N2O-N in 1980 to 313 Gg N2O-N in 2007, and were determined mainly by upland emissions (accounting for 67.8–88.6% of total emissions from 1980 to 2007). Synthetic N fertilizers played a major role in N2O emissions from agricultural land, and the magnitude of the contributions to total direct N2O emissions made by different amendments was synthetic N fertilizer > manure > straw, representing about 78, 15, and 6% of total direct N2O emissions, respectively, between 2000 and 2007. The spatial pattern of total N2O emissions in 2007 in China shows that high direct N2O emissions occurred mainly in the north and in the Sichuan Basin in the southwest. The provinces with the highest emissions were Henan (35.4 Gg) and Shandong (31.6 Gg) and Tibet had the lowest (0.65 Gg). High direct N2O emissions per unit of arable land occurred mainly on the North China Plain and the southeast coast. The mean value nationally was 2.52 kg N ha−1, with 18 provinces above this value and with emissions of >4.0 kg N ha−1 in Beijing, Tianjin and in Jiangsu, Shandong, Fujian and Henan provinces.

scholarly journals New estimates of direct N<sub>2</sub>O emissions from Chinese croplands from 1980 to 2007 using localized emission factors

2011 ◽  
Vol 8 (4) ◽  
pp. 6971-7006 ◽  
Author(s):  
B. Gao ◽  
X. T. Ju ◽  
Q. Zhang ◽  
P. Christie ◽  
F. S. Zhang
Keyword(s):  
North China ◽  
Agricultural Land ◽  
Original Data ◽  
Emission Factors ◽  
Paddy Fields ◽  
Nitrogen Fertilizers ◽  
Annual Rate ◽  
Anthropogenic Sources ◽  
Cube Root ◽  
N2o Emissions

Abstract. Nitrous oxide (N2O) is a long-lived greenhouse gas with a large radiation intensity and it is emitted mainly from agricultural land. Accurate estimates of total direct N2O emissions from croplands on a country scale are important for global budgets of anthropogenic sources of N2O emissions and for the development of effective mitigation strategies. The objectives of this study were to re-estimate direct N2O emissions using localized emission factors and a database of measurements from Chinese croplands. We obtained N2O emission factors for paddy fields (0.41 %) and uplands (1.05 %) from a normalization process through cube root transformation of the original data after comparing the results of normalization from the original values, logarithmic and cube root transformations because the frequency of the original data was not normally distributed. Direct N2O emissions from Chinese croplands from 1980 to 2007 were estimated using IPCC (2006) guidelines combined with separate localized emission factors for paddy fields and upland areas. Direct N2O emissions from paddy fields showed little change, increasing by 11 % with an annual rate of increase of 0.4 % from 29.8 Gg N2O-N in 1980 to 33.1 Gg N2O-N in 2007. In contrast, emissions from uplands changed dramatically, increasing by 296 % with an annual rate of 10.9 % from 64.4 Gg N2O-N in 1980 to 255.3 Gg N2O-N in 2007. Total direct N2O emissions from Chinese croplands increased by 206 % with an annual rate of 7.6 % from 94.2 Gg N2O-N in 1980 to 288.4 Gg N2O-N in 2007, and were determined mainly by upland emissions (accounting for 68.4–88.5 % of total emissions from 1980 to 2007). Synthetic nitrogen fertilizers played a major role in N2O emissions from agricultural land, and the magnitude of the contributions to total direct N2O emissions made by different amendments was synthetic N fertilizer > manure > straw, representing about 77, 16, and 6.5 % of total direct N2O emissions, respectively, between 2000 and 2007. The spatial pattern of total N2O emissions in 2007 in China shows that high direct N2O emissions occurred mainly in north China and in the Sichuan Basin in the southwest. The provinces with the highest emissions were Henan (32.6 Gg) and Shandong (29.1 Gg) and Tibet had the lowest (0.6 Gg). High direct N2O emissions per unit of arable land occurred mainly on the North China Plain and the southeast coast. The mean value nationally was 2.36 kg N ha−1, with 17 provinces above this, and with emissions of >4.0 kg N ha−1 in Beijing and in Jiangsu and Henan provinces.

scholarly journals Modelling Methane and Nitrous Oxide Emissions from Rice Paddy Wetlands in India Using Artificial Neural Networks (ANNs)

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2169 ◽  
Author(s):  
Tabassum Abbasi ◽  
Tasneem Abbasi ◽  
Chirchom Luithui ◽  
Shahid Abbas Abbasi
Keyword(s):  
Nitrous Oxide ◽  
Paddy Fields ◽  
Anthropogenic Sources ◽  
Nitrous Oxide Emissions ◽  
Soil Conditions ◽  
N2o Emissions ◽  
Ch4 Emissions ◽  
Artificial Neural ◽  
Ch4 And N2o

Paddy fields, which are shallow man-made wetlands, are estimated to be responsible for ~11% of the total methane emissions attributed to anthropogenic sources. The role of water use in driving these emissions, and the apportioning of the emissions to individual countries engaged in paddy cultivation, are aspects that have been mired in controversy and disagreement. This is largely due to the fact that methane (CH4) emissions not only change with the cultivar type but also regions, climate, soil type, soil conditions, manner of irrigation, type and quantity of fertilizer added—to name a few. The factors which can influence these aspects also encompass a wide range, and have origins in causes which can be physical, chemical, biological, and combinations of these. Exceedingly complex feedback mechanisms, exerting different magnitudes and types of influences on CH4 emissions under different conditions, are operative. Similar is the case of nitrous oxide (N2O); indeed, the present level of understanding of the factors which influence the quantum of its emission is still more patchy. This makes it difficult to even understand precisely the role of the myriad factors, less so model them. The challenge is made even more daunting by the fact that accurate and precise data on most of these aspects is lacking. This makes it nearly impossible to develop analytical models linking causes with effects vis a vis CH4 and N2O emissions from paddy fields. For situations like this the bioinspired artificial intelligence technique of artificial neural network (ANN), which can model a phenomenon on the basis of past data and without the explicit understanding of the mechanism phenomena, may prove useful. However, no such model for CH4 or N2O has been developed so far. Hence the present work was undertaken. It describes ANN-based models developed by us to predict CH4 and N2O emissions using soil characteristics, fertilizer inputs, and rice cultivar yield as inputs. Upon testing the predictive ability of the models with sets of data not used in model development, it was seen that there was excellent agreement between model forecasts and experimental findings, leading to correlations coefficients of 0.991 and 0.96, and root mean square error (RMSE) of 11.17 and 261.3, respectively, for CH4 and N2O emissions. Thus, the models can be used to estimate CH4 and N2O emissions from all those continuously flooded paddy wetlands for which data on total organic carbon, soil electrical conductivity, applied nitrogen, phosphorous and potassium, NPK, and grain yield is available.

scholarly journals The Conversion of Rice Field Functions in North Badung

2020 ◽  
Vol 8 (2) ◽  
pp. 176
Author(s):  
Ni Made Ayu Krisna Wati ◽  
I Made Sudarma ◽  
Widhianthini Widhianthini
Keyword(s):  
Rice Field ◽  
Agricultural Land ◽  
Rice Fields ◽  
Paddy Fields ◽  
Interpretive Structural Modeling ◽  
Pests And Diseases ◽  
The North ◽  
Analysis Technique ◽  
Paddy Land ◽  
Management Priorities

Land is the main resource in carrying out development. Reduction of land area, especially agricultural land for development also has an impact on the area of agricultural land in Bali, especially in Badung Regency. The construction of accommodation to support the tourism sector led to the conversion of agricultural land in Badung Regency, which is mostly found in South Badung. North Badung, which does not have as many attractions as those in South Badung, has in fact also experienced the conversion of agricultural land, especially rice fields, as was the case in the Abiansemal and Mengwi Sub-Districts. The purpose of this study is to determine the factors that cause the conversion of paddy fields in the North Badung sub-district and determine the strategy to control the conversion of wetland in North Badung. The technique for determining key informants was done by purposive sampling with a total of 20 people. The analysis technique used is the Interpretive Structural Modeling (ISM) analysis. The results showed that the factors that caused the conversion of paddy fields or wetland in North Badung were economic elements, namely rice farming income, harvest price stability, access to crop marketing and paddy land prices. Social elements, namely family participation in managing rice fields, the influence of modernization on agriculture, the number of family members who are covered and regeneration of rice field management. The third elements is the environment, namely the level of water irrigation of rice fields, pests and diseases and housing needs due to increasing population. The strategy of controlling wetland conversion in North Badung that can be done based on short-term management priorities in the independent sector is the Millennial Farmer program.

scholarly journals Spatial-Temporal Land Use and Land Cover Changes in Urban Areas Using Remote Sensing Images and GIS Analysis: The Case Study of Opole, Poland

Geosciences ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 312
Author(s):  
Barbara Wiatkowska ◽  
Janusz Słodczyk ◽  
Aleksandra Stokowska
Keyword(s):  
Remote Sensing ◽  
Land Use ◽  
Land Cover ◽  
Satellite Imagery ◽  
Urban Areas ◽  
Agricultural Land ◽  
Urban Expansion ◽  
Landsat 8 ◽  
Rate Of Increase ◽  
Management Procedures

Urban expansion is a dynamic and complex phenomenon, often involving adverse changes in land use and land cover (LULC). This paper uses satellite imagery from Landsat-5 TM, Landsat-8 OLI, Sentinel-2 MSI, and GIS technology to analyse LULC changes in 2000, 2005, 2010, 2015, and 2020. The research was carried out in Opole, the capital of the Opole Agglomeration (south-western Poland). Maps produced from supervised spectral classification of remote sensing data revealed that in 20 years, built-up areas have increased about 40%, mainly at the expense of agricultural land. Detection of changes in the spatial pattern of LULC showed that the highest average rate of increase in built-up areas occurred in the zone 3–6 km (11.7%) and above 6 km (10.4%) from the centre of Opole. The analysis of the increase of built-up land in relation to the decreasing population (SDG 11.3.1) has confirmed the ongoing process of demographic suburbanisation. The paper shows that satellite imagery and GIS can be a valuable tool for local authorities and planners to monitor the scale of urbanisation processes for the purpose of adapting space management procedures to the changing environment.

scholarly journals Agriculture and land use in the North of Russia: Case study of Karelia and Yakutia

2020 ◽  
Vol 12 (1) ◽  
pp. 1497-1511
Author(s):  
Alexey Naumov ◽  
Varvara Akimova ◽  
Daria Sidorova ◽  
Mikhail Topnikov
Keyword(s):  
Land Use ◽  
Agricultural Development ◽  
Agricultural Land ◽  
Geographical Location ◽  
Special Role ◽  
Sources Of Information ◽  
Local Conditions ◽  
Climate Conditions ◽  
The North ◽  
The Republic

AbstractDespite harsh climate, agriculture on the northern margins of Russia still remains the backbone of food security. Historically, in both regions studied in this article – the Republic of Karelia and the Republic of Sakha (Yakutia) – agricultural activities as dairy farming and even cropping were well adapted to local conditions including traditional activities such as horse breeding typical for Yakutia. Using three different sources of information – official statistics, expert interviews, and field observations – allowed us to draw a conclusion that there are both similarities and differences in agricultural development and land use of these two studied regions. The differences arise from agro-climate conditions, settlement history, specialization, and spatial pattern of economy. In both regions, farming is concentrated within the areas with most suitable natural conditions. Yet, even there, agricultural land use is shrinking, especially in Karelia. Both regions are prone to being affected by seasonality, but vary in the degree of its influence. Geographical location plays special role, and weaknesses caused by remoteness to some extent become advantage as in Yakutia. Proximity effect is controversial. In Karelia, impact of neighboring Finland is insignificant compared with the nearby second Russian city – Saint Petersburg.

scholarly journals Czech Building Stock: Renovation Wave Scenarios and Potential for CO2 Savings until 2050

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2455
Author(s):  
Antonín Lupíšek ◽  
Tomáš Trubačík ◽  
Petr Holub
Keyword(s):  
Climate Change ◽  
Carbon Dioxide ◽  
Carbon Dioxide Emissions ◽  
Climate Change Mitigation ◽  
Emission Factors ◽  
Anthropogenic Sources ◽  
Building Stock ◽  
National Debate ◽  
Energy Consumptions ◽  
Change Mitigation

One of the major anthropogenic sources of greenhouse gases is the operation of building stock. Improving its energy efficiency has the potential to significantly contribute to achieving climate change mitigation targets. The purpose of this study was to roughly estimate such potential for the operation of the national building stock of Czechia to steer the national debate on the development of related national plans. The estimation is based on a simplified energy model of the Czech building stock that consists of sub-models of residential and nonresidential building stocks, for which their future energy consumptions, shares of energy carriers and sources, and emission factors were modeled in four scenarios. Uncertainties from the approximation of the emission factors were investigated in a sensitivity analysis. The results showed that the operation of the Czech building stock in 2016 totaled 36.9 Mt CO2, which represented 34.6% of the total national carbon dioxide emissions. The four building stock scenarios could produce reductions in the carbon dioxide emissions of between 28% and 93% by 2050, when also considering on-side production from photovoltaics. The implementation of the most ambitious scenario would represent a drop in national CO2 yearly emissions by 43.2% by 2050 (compared to 2016).

scholarly journals Does natural selection favour taller stature among the tallest people on earth?

2015 ◽  
Vol 282 (1806) ◽  
pp. 20150211 ◽  
Author(s):  
Gert Stulp ◽  
Louise Barrett ◽  
Felix C. Tropf ◽  
Melinda Mills
Keyword(s):  
Natural Selection ◽  
Reproductive Success ◽  
The Netherlands ◽  
Child Survival ◽  
Average Height ◽  
Tall Stature ◽  
Age At First Birth ◽  
Number Of Children ◽  
The North ◽  
Rate Of Increase

The Dutch are the tallest people on earth. Over the last 200 years, they have grown 20 cm in height: a rapid rate of increase that points to environmental causes. This secular trend in height is echoed across all Western populations, but came to an end, or at least levelled off, much earlier than in The Netherlands. One possibility, then, is that natural selection acted congruently with these environmentally induced changes to further promote tall stature among the people of the lowlands. Using data from the LifeLines study, which follows a large sample of the population of the north of The Netherlands ( n = 94 516), we examined how height was related to measures of reproductive success (as a proxy for fitness). Across three decades (1935–1967), height was consistently related to reproductive output (number of children born and number of surviving children), favouring taller men and average height women. This was despite a later age at first birth for taller individuals. Furthermore, even in this low-mortality population, taller women experienced higher child survival, which contributed positively to their increased reproductive success. Thus, natural selection in addition to good environmental conditions may help explain why the Dutch are so tall.

Recession Contributes To Slowest Annual Rate Of Increase In Health Spending In Five Decades

2011 ◽  
Vol 30 (1) ◽  
pp. 11-22 ◽  
Author(s):  
Anne Martin ◽  
David Lassman ◽  
Lekha Whittle ◽  
Aaron Catlin ◽  
Keyword(s):  
Health Spending ◽  
Annual Rate ◽  
Rate Of Increase

Imitative Suicide in a Cohesive Organization: Observations from a Case Study

1994 ◽  
Vol 79 (3_suppl) ◽  
pp. 1475-1478
Author(s):  
Atholl T. Malcolm ◽  
Michel Pierre Janisse
Keyword(s):  
High Risk ◽  
Clinical Intervention ◽  
Individual Therapy ◽  
Annual Rate ◽  
Job Description ◽  
Misleading Information ◽  
The North ◽  
Military Unit ◽  
Anxiety Depression

Three suicides occurred within 3 years in a military unit of 35 individuals. This represented an annual rate 220 times the North American average. A clinical intervention was requested by medical authorities, the goal being to minimize the risk of further deaths. Group and individual therapy was conducted over 3 days and ongoing referrals were made as necessary. In addition, measures of anxiety, depression, and hostility were obtained from this unit and from a unit equivalent in size and job description to examine whether these constructs could be used diagnostically. Analysis of the data indicated that differences in mean scores between the units yielded potentially misleading information, although on an individual basis scores were useful in identifying clients at risk of suicide. When those who personally knew one or more of the deceased were compared with those who did not, variability of scores in conjunction with interviews was helpful in identifying relatively high-risk subgroups.

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