Average Greenhouse Gas Emissions Research Articles

Greenhouse gas emissions of conventional and alternative vehicles: Predictions based on energy policy analysis in South Korea

This paper compares the well-to-wheel (WTW) greenhouse gas (GHG) emissions of representative vehicle types–internal combustion engine vehicle (ICEV), hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV), battery electric vehicle (BEV), and fuel cell electric vehicle (FCEV)–in the future (2030) based on a WTW analysis for the present (2017) and an analysis of various energy policies that could affect future emissions. South Korea was selected as the target region because it has detailed energy policies related to alternative vehicles. The WTW analysis for the present was performed based on three sets of subordinate analyses: (1) life cycle analyses of eight base fuels; (2) life cycle analyses of electricity and hydrogen; and (3) analyses of the fuel economies of seven vehicle types. From the WTW analysis for the present, the national average WTW GHG emissions of ICEV-gasoline, ICEV-diesel, ICEV-liquefied petroleum gas, HEV, PHEV, BEV, and FCEV were calculated as 225, 233, 201, 159, 133, 109, and 55 g-CO2-eq./km, respectively. For calculating the WTW GHG emissions in the future, two policies regarding electricity production and three policies regarding hydrogen production were analysed. Three cases with varying the degrees of improvements in fuel economies were considered. Six future scenarios were constructed, and each scenario represented the case in which each energy policy is enacted. In the reference scenario, for compact car, the WTW GHG emissions of ICEVs-gasoline, HEV, PHEV, BEV-200 mile, FCEV were analysed as 161, 110, 97, 86, and 91 g-CO2-eq./km, respectively. The differences between ICEV/HEV and BEV were predicted to decrease in the future mainly due to larger improvements of ICEV/HEV in fuel economies compared to that of BEV. The future life cycle GHG emissions of electricity and hydrogen were calculated according to energy policy. Both two policies regarding power generation were confirmed to increase the benefits of utilizing BEVs, but current energy policy regarding hydrogen production were confirmed to decrease the benefits of utilizing FCEVs. Based on the comprehensive results of this study, a framework was proposed to evaluate the impacts of an energy policy regarding electricity and hydrogen production on the benefits of using BEVs and FCEVs compared to using HEVs and ICEVs. This framework can also be utilized in other countries when they assess and establish their energy policies.

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

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.

Lignocellulosic Ethanol in a Greenhouse Gas Emission Reduction Obligation System—A Case Study of Swedish Sawdust Based-Ethanol Production

A greenhouse gas (GHG) emission reduction obligation system has been implemented in the Swedish road transport sector to promote the use of biofuels. For transportation fuel suppliers to fulfil this obligation, the volume of biofuel required decreases with decreasing life cycle GHG emission for the biofuel, linking lower GHG emission to higher economic value. The aim of this study was to investigate how the economic competitiveness of a Swedish emerging lignocellulosic-based ethanol production system would be influenced by the reduction obligation. The life cycle GHG emission for sawdust-based ethanol was calculated by applying the method advocated in the EU Renewable Energy Directive (RED II). The saving in GHG emissions, compared with fossil liquid transportation fuels, was 93% for a potential commercial production system in southern Sweden. This, in turn, will increase the competitiveness of sawdust-based ethanol compared to the mainly crop-based ethanol currently used in the Swedish biofuel system, which has an average GHG emission saving of 68%, and will allow for an almost 40% higher price of sawdust-based ethanol, compared to the current price of ethanol at point of import. In a future developed, large-scale market of advanced ethanol, today’s GHG emission reduction obligation system in Sweden seems to afford sufficient economic advantage to make lignocellulosic ethanol economically viable. However, in a short-term perspective, emerging lignocellulosic-based ethanol production systems are burdened with economic risks and therefore need additional economic incentives to make a market introduction possible.

Diel pattern driven by free convection controls leaf-cutter ant nest ventilation and greenhouse gas emissions in a Neotropical rain forest.

Leaf-cutter ant nests are biogeochemical hot spots where ants live and import vegetation to grow fungus. Metabolic activity and (in wet tropical forests) soil gas flux to the nest may result in high nest CO2 concentrations if not adequately ventilated. Wind-driven ventilation mitigates high CO2 concentrations in grasslands, but little is known about exchange for forest species faced with prolonged windless conditions. We studied Atta cephalotes nests located under dense canopy (leaf area index > 5) in a wet tropical rainforest in Costa Rica, where wind events are infrequent. We instrumented nests with thermocouples and flow-through CO2 sensing chambers. The results showed that CO2 concentrations exiting leaf-cutter ant nests follow a diel pattern with higher values at night. We developed an efflux model based on pressure differences that evaluated the observed CO2 diel pattern in terms of ventilation by (1) free convection (warm, less dense air rises out the nest more prominently at night) and (2) episodic wind-forced convection events providing occasional supplemental ventilation during daytime. Average greenhouse gas emissions were estimated through nest vents at about 78kg CO2eq nest-1year-1. At the ecosystem level, leaf-cutter ant nest vents accounted for 0.2% to1% of total rainforest soil emissions. In wet, clayey tropical soils, leaf-cutter ant nests act as free convection-driven conduits for exporting CO2 and other greenhouse gases produced within the nest (fungus and ant respiration, refuse decay), and by roots and soil microbes surrounding the nest. This allows A. cephalotes nests to be ventilated without reliable wind conditions.

Comparison of Greenhouse Gas Emissions Per Capita Per Year Among Countries Considering Methane Emissions

The cumulative emissions of CO2 and CH4 had a great impact on the global climate, and the responsibility of countries around the world to achieve greenhouse gas (GHG) emission control goals should be based on the concept of fairness and sustainable development. In this paper, from the perspective of interpersonal equity, based on the annual GHG emissions per capita, using the CO2 and CH4 emissions data of 23 major countries from 1961 to 2017, the ratio for GHG emission per capita per year and the ratio for carbon dioxide emission per capita per year in various countries were calculated with 1961 and 1990 as the starting years, the countries were also sequenced and sorted to analyze the extent to which major countries occupy limited global emissions space at different time scales and GHG ranges. The results showed that the ratio of GHG emission per capita per year in developed countries such as the United States and Canada were far higher than the world average, China was significantly lower than the average, India was much lower than the average. In addition, lengthening the time scale and incorporating the methane emissions from the planting and breeding industry (agriculture activities) had a significant impact on the the ratio of GHGemission per capita and national classification. It can be more conducive to judge the world's average annual GHG emissions, reflect the global emission space occupied by each countries comprehensively and objectively, and scientifically support policymakers in formulating action plan for GHGemission reduction and control, which was of practical significance.

Influence of nitrogen application on wheat crop performance, soil properties, greenhouse gas emissions and carbon footprint in central Bhutan

In Bhutan, wheat (Triticum aestivum L.) is an important staple crop and its productivity is low due to poor soil fertility and inadequate external inputs. Hence, effects of four levels of nitrogen (N) [0, 50, 80 and 100 kg N ha−1] on wheat crop and soil properties were examined for two consecutive years (2012 and 2013) in a rice-wheat rotation. The experiment was set up in a randomized complete block design and the treatments replicated three times. In addition, greenhouse gas (GHG) emission was analyzed both per unit area and per kilogram of wheat grain to determine the emission-intense sources. Data were subjected to analysis of variance. Among the treatments, 100 kg N ha−1 had the largest effect on grain yield and dry biomass and on plant height. Significant correlations were detected for the N rates vs. dry biomass. However, correlations between N rates vs. soil N, C:N ratio and pH were significant for 2013 only. The average GHG emissions were 1114.2 kg CO2e ha−1 and 0.533 kg CO2e kg−1 grain and the emissions per hectare were highly influenced by N rates whereas the emissions per kilogram of grain were influenced by grain yield. We concluded that, in Bhutan, the application of N-fertilizer significantly enhanced wheat productivity and soil health at N rates of ≥50 kg N ha−1. Further, the results indicated potentials to increase wheat yield with lower GHG emissions through improved N management.

Impacts of nitrogen management and organic matter application on nitrous oxide emissions and soil organic carbon from spring maize fields in the North China Plain

Soil carbon dioxide (CO2) and nitrous oxide (N2O) emissions and carbon (C) sequestration are important processes for determining net greenhouse gas (GHG) emissions from maize fields. Farming management practices (FMPs) substantially affect crop productivity, soil organic carbon (SOC), and N2O emissions. However, relative knowledge is not sufficient, and further research is required for sustainable agriculture development. A multi-year experiment was performed on a spring maize field in the North China Plain (NCP) to quantify changes in SOC stocks, N2O emissions, and maize yields. Seven treatments were involved in the experiment, including no N fertilization (CK), farmers’ conventional N fertilization (FP), sole application of manure N (M), a combination of M and FP (MFP), FP combined with returned maize straw (SFP), fertilization with reduced synthetic N amount (RN), and fertilization with both reduced synthetic and manure N (RMN). The field measurements demonstrated that urea applications and returned maize straw increased N2O emission. The seasonal total N2O emissions under FP were significantly (P < 0.05) higher than those under CK by 176% to 222% and lower than those under SFP by 20% to 61% throughout the three maize growing seasons. The application of organic manure or maize straw enhanced SOC storage for the studied cropping system. The SOC stocks were relatively high in the plots that received applications of organic manure or maize straw, with the SOC stock of the M plot being significantly higher (P < 0.05) than that of the CK, FP, SFP, RN, and RMN plots in 2016 after eight years of manure amendments. The average net GHG emission from 2012 to 2014 was 203 kg CO2 equivalent ha−1 year−1 (i.e., a net GHG source) under FP. The other treatments converted the maize fields from net GHG sources to GHG sinks. By considering both the maize yields and net GHG emissions, RMN would be an optimal management option, although MFP, SFP, and RN also mitigated the GHG emissions and maintained the yields. Large variations were observed in the contributions of the SOC changes and N2O emissions to net GHG emissions among the treatments. The large variations demonstrate the need to consider both SOC changes and N2O emissions when evaluating the impacts of alternative FMPs on net GHG emissions.

Achieving energy efficiency with medium voltage variable speed drives for ventilation-on-demand in South African mines

The sustainability of the mining industry is contingent on the industry's ability to improve upon the status quo of operational efficiency. The advancement of energy efficient technologies coupled with modern strategies have resulted in large industrial energy efficiency improvements, lowering emissions and wastage. Mine ventilation fans in South Africa were identified as large energy consumers with potential for efficiency improvements, with the installation of medium voltage variable speed drive technologies. An extensive energy audit was conducted on ten mine ventilation networks to calculate the feasibility inter alia cost savings, energy savings and greenhouse gas emission reductions under varying airflow conditions. Two ventilation-on-demand applications were considered namely, constant speed reduction- and dynamic applications. The financial indicators revealed it is economically viable for the implementation of medium voltage variable speed drives as part of the ventilation-on-demand applications. The energy audit revealed that a total annual electrical energy saving of 179 421 MWh could be achieved with the implementation of the ventilation-on-demand applications. The resulting cost saving is estimated at US$11.57-million with an average payback period of 9 months. The average greenhouse gas emission reduction is calculated as 53% per annum. The feasibility of installing medium voltage variable speed drives on South African mine ventilation fans as part of ventilation-on-demand applications to improve efficiency and lower emissions was proven. The results emphasise the importance of such audits to illustrate the underutilised resources available to increase mine sustainability and subsequently profitability.

Decision-support framework for the environmental assessment of water treatment systems

Environmental assessments require the development and analysis of a large amount of data. Decision-makers must manage considerable amounts of information just to obtain a viable set of alternatives. The environmental assessment proposed in this study is a decision-support framework that facilitates obtaining results that endorse the decision-making process.This study aims to provide a fast and straightforward analysis of the influence of energy consumption in water treatment systems (energy-for-water) and its impact onto the environment, considering water quality requirements, water distribution systems, and how different energy combination setups affect these variables. The framework was applied to countries on the seashore experiencing water scarcity distress and world average greenhouse gas emissions regimes as examples, but it can also be applied to other types of systems.Energy-for-water greenhouse gas emissions can be decreased through the awareness-related measures reflected in the selection of energy sources, changing water desalination process, optimizing water intake, choosing water reuse, and using untreated seawater in industrial processes. Countries with the highest greenhouse gas emissions continue obtaining electricity from coal. Likewise, greenhouse gas emissions are lower in countries using nuclear energy as a source of electricity. However, the reliance on nuclear energy often depends on stakeholder approval.

Greenhouse gas emissions, total food spending and diet quality by share of household food spending on red meat: results from a nationally representative sample of US households.

To determine if US household food purchases with lower levels of red meat spending generate lower life-cycle greenhouse gas emissions (GHGE), greater nutritional quality and improved alignment with the Dietary Guidelines for Americans. Affordability of purchasing patterns by red meat spending levels was also assessed. Household food purchase and acquisition data were linked to an environmentally extended input-output life-cycle assessment model to calculate food GHGE. Households (n 4706) were assigned to quintiles by the share of weekly food spending on red meat. Average weekly kilojoule-adjusted GHGE, total food spending, nutrients purchased and 2010 Healthy Eating Index (HEI-2010) were evaluated using ANOVA and linear regression. USA.ParticipantsHouseholds participating in the 2012-2013 National Household Food Acquisition and Purchase Survey. There was substantial variation in the share of the household food budget spent on red meat and total spending on red meat. The association between red meat spending share and total food spending was mixed. Lower red meat spending share was mostly advantageous from a nutritional perspective. Average GHGE were significantly lower and HEI-2010 scores were significantly higher for households spending the least on red meat as a share of total food spending. Only very low levels of red meat spending as a share of total food spending had advantages for food affordability, lower GHGE, nutrients purchased and diet quality. Further studies assessing changes in GHGE and other environmental burdens, using more sophisticated analytical techniques and accounting for substitution towards non-red meat animal proteins, are needed.

The choice of new private and benefit cars vs. climate and transportation policy in Sweden

Dedicated to show climate leadership, Sweden has committed to cut 70% of greenhouse-gas (GHG) emissions in the domestic transportation sector by 2030 compared to 2010 levels (except flights). This study evaluated the environmental impacts of three recent new car policies. Based on questionnaires and market supply data, multinomial logit discrete choice models were developed for private buyers and individuals with company cars for private use, denoted benefit cars. Estimates indicated that preferences among individuals with benefit cars were generally in favor of Alternative Fuel Vehicles (AFVs) as compared to gasoline cars, in contrast with private consumers (ceteris paribus). Thus, the company car market seemed to be the main gateway for AFVs into the fleet; however, average GHG emissions per car sold were similar in both buyer segments, which was likely related to stronger preferences for larger and more expensive benefit cars. The results indicated that subsidies to private buyers would be influential only if they decreased the costs of AFVs as compared to conventional vehicles, and that none of the investigated policies had been very effective in shifting choices in favor of AFVs. Reduced fringe benefits tax for AFVs, annually worth up to €1100, resulted in only 0.7% lower average carbon emissions. A ‘Super Green Car’ premium, worth approximately €2000–€4000 at the time of purchase, decreased emissions by 0.4% among private consumers, twice the impact of a five-year tax-exemption for ‘Green Cars’. It appears that more stringent policies are needed to more substantially reduce GHG emissions from new cars.

Meeting National Emissions Reduction Obligations: A Case Study of Australia

Akin to a public good, emissions reduction suffers from the ‘free rider’ syndrome. Although many countries claim that they are meeting their greenhouse gas (GHG) emissions reduction commitments, the average global temperature and GHG emissions continue to rise. This has led to growing speculation that some countries may be taking advantage of the system by effectively exploiting a range of loopholes in global agreements. Using a case study approach, we critically review the evidence from Australia, exploring how Australia has participated in global climate change negotiations and the way in which this emissions intensive country’s national emissions reduction obligations have been met. The findings suggest that: (1) successful negotiation to include Article 3.7 (‘Adjusting the 1990 Baseline’ or ‘the Australia Clause’) in the Kyoto Protocol significantly favored Australia’s ability to meet its First Kyoto Commitment (2008–2012); and (2) successful bargaining for the accounting rule that allowed carbon credits from the first commitment period to be carried over to the second commitment period of the Kyoto Protocol benefitted Australia by 128 MtCO2e. At the national level, a lack of bipartisan political support for an effective mechanism to drive emissions reduction has also been problematic. While the introduction of the Carbon Pricing Mechanism (CPM) in 2012 reduced emissions from electricity production from about 199.1 MtCO2e to 180.8 MtCO2e in 2014, a change of government led to the abolition of the CPM in 2014 and emissions from electricity production subsequently rose to 187 MtCO2e in 2015 and 189 MtCO2e in 2016 with adverse impacts in many sectors as well as Australia’s overall emissions. The current Australian government continues to undermine its commitment to mitigation and the integrity and credibility of its own emissions reductions policy, introducing a softer ‘calculated baseline’ for its own Safeguard Mechanism, which allows companies to upwardly adjust their calculated baselines on the basis of their highest expected emissions, permitting emissions in excess of their historical emissions. While disappointing in the context of the global emissions reduction project, Australia’s actions are sadly not unique and we also provide examples of loopholes exploited by countries participating in a range of other negotiations and emissions reduction projects. Such strategies undoubtedly serve the short-term political and economic interests of these countries; however, it is increasingly apparent that the cumulative impact of such tactics will ultimately impact the entire global community.

Assessments of greenhouse gas (GHG) emissions from stainless steel production in China using two evaluation approaches

In recent years, global warming has become a growing concern around the world, and greenhouse gases (GHG) are its major cause. In the current study, the GHG emissions from stainless steel production in Mainland China was evaluated based on two approaches. One (i.e., Approach I) was based on the data, which were collected from a life cycle inventory database (Ecoinvent). The second evaluation (i.e., Approach II) was performed according to the 2015 comprehensive energy consumption data of the Chinese stainless steel industry. When Approach I was employed, the results demonstrated that 1.44 kg CO2‐e of total GHG emissions were generated for producing 1 kg of stainless steel. When adopting Approach II, the average GHG emissions based on comprehensive energy consumption from four stainless steel manufacturers in Mainland China were calculated to be 1.76 kg CO2‐e/kg stainless steel. Further, the main hotspot area of GHG emissions for stainless steel production was found to be the blast furnace (BF) process, based on Approach I. Accordingly, employing an independent electric arc furnace (EAF) instead of a BF‐EAF, as well as choosing clean technologies and updating obsolete and low‐efficiency equipment, is recommended. It is expected that these two approaches can help stakeholders formulate a sustainable strategy for stainless steel production. And more broadly, provide some insights into adopting an appropriate framework for the evaluation of GHG emissions in industrial areas. © 2019 American Institute of Chemical Engineers Environ Prog, 38: 47–55, 2019

Land Use Change and the European Biofuels Policy: The expansion of oilseed feedstocks on lands with high carbon stocks

The focus of this article is on the potential land use change impacts associated with the oilseed-based biodiesel consumption. The three main crops used for biodiesel production to date are oilseed rape (OSR), soybeans and oil palm. Therefore, the objective of this paper is to provide a technical assessment of potential land use change arising from the growth of these three major crops at global level, obtained through a broad country-level analysis for their respective major producing countries. The article presents an historical data analysis, evaluating the interaction between the expansion and contraction of these three crops over the last three decades (with a closer look from 2008) together with the carbon stock changes to the land. We categorise the land use by its carbon stock and resulting carbon stock changes from land use change. Crops aimed at the production of ethanol, such as maize (corn), sugarcane, wheat, cassava and sugar beet, although extremely relevant for biofuel policies, are not the subject of this present study. While we did not know at the time of writing this report how the term “significant” would be defined in the EU delegated act we concluded from the analysis of the historical data and using the high ILUC-risk definition as it stands, that the emissions associated with palm and soy are significant. For oil palm, we take Indonesia and Malaysia as proxy for the global position. We calculate an average expansion of 29% on high carbon stock land. For soy, we calculate a global average of 19% expansion. We calculate the global average greenhouse gas emissions intensities based on the ILUC-risks as 56 gCO2eq/MJ for soy oil and 108 gCO2eq/MJ for palm oil. Future projections (OECD-FAO, 2017) suggest these numbers could drop significantly. We do not find evidence for high ILUC-risk expansion of oilseed rape.

The Effects of System Changes in Grazed Dairy Farmlet Trials on Greenhouse Gas Emissions.

Simple SummaryDairy farm system practices aimed at reducing nitrate leaching can also reduce emissions of the greenhouse gases methane and nitrous oxide. A study comparing ‘current’ and ‘improved’ grazed dairy system practices showed that ‘improved’ systems generally produced lower greenhouse gas emissions while milk production was maintained. The amount of feed eaten per hectare was the key driver of total greenhouse gas emissions per area, with ‘improved’ systems generally exhibiting lower total enteric methane and less N flowing through the herd.An important challenge facing the New Zealand (NZ) dairy industry is development of production systems that can maintain or increase production and profitability, while reducing impacts on receiving environments including water and air. Using research ‘farmlets’ in Waikato, Canterbury, and Otago (32–200 animals per herd), we assessed if system changes aimed at reducing nitrate leaching can also reduce total greenhouse gas (GHG) emissions (methane and nitrous oxide) and emissions intensity (kg GHG per unit of product) by comparing current and potential ‘improved’ dairy systems. Annual average GHG emissions for each system were estimated for three or four years using calculations based on the New Zealand Agricultural Inventory Methodology, but included key farmlet-specific emission factors determined from regional experiments. Total annual GHG footprints ranged between 10,800 kg and 20,600 kg CO2e/ha, with emissions strongly related to the amount of feed eaten. Methane (CH4) represented 75% to 84% of the total GHG footprint across all modelled systems, with enteric CH4 from lactating cows grazing pasture being the major source. Excreta deposition onto paddocks was the largest source of nitrous oxide (N2O) emissions, representing 7–12% of the total GHG footprint for all systems. When total emissions were represented on an intensity basis, ‘improved’ systems are predicted to generally result in lower emissions intensity. The ‘improved’ systems had lower GHG footprints than the ‘current’ system, except for one of the ‘improved’ systems in Canterbury, which had a higher stocking rate. The lower feed supplies and associated lower stocking rates of the ‘improved’ systems were the key drivers of lower total GHG emissions in all three regions. ‘Improved’ systems designed to reduced N leaching generally also reduced GHG emissions.

Life Cycle Assessment of Commercial Delivery Trucks: Diesel, Plug-In Electric, and Battery-Swap Electric

The development of electric delivery trucks has attracted much attention in recent years. The purpose of this study is to assess the greenhouse gas (GHG) emissions and the total cost of ownership (TCO) of light-duty and medium-duty diesel trucks (DTs), plug-in electric trucks (ETs), and battery-swap ETs. A simplified life cycle assessment (LCA) method and a TCO assessment method are used. Numerical results show that the average GHG emission of light-duty ETs is 69% lower than that of light-duty DTs, while that of medium-duty ETs is 9.8% higher than that of medium-duty DTs. As regards TCO, those of plug-in ETs and battery-swap ETs are 37.8% lower and 21% higher than that of light-duty DTs, while for medium-duty trucks, the TCO of plug-in and battery-swap ETs are 6.7% lower and 18.9% higher than that of medium-duty DTs. The main conclusion of this paper is that light-duty plug-in ETs exhibit the best performance in terms of cost saving and GHG emission reduction. Moreover, ETs show more advantages than DTs when the frequency of use is higher or when the driving environment is more congested.

Carbon Footprint Analyses and Potential Carbon Emission Reduction in China’s Major Peach Orchards

An excess of material input in fruit orchards has brought serious environmental problems, particularly in China. However, studies on the estimation of greenhouse gas (GHG) emissions in peach orchards are limited. In this study, based on questionnaire surveys in major peach-producing regions, including the North China Plain (n = 214), as well as northwest (n = 22) and southwest (n = 33) China, the carbon footprints (CFs) of these orchards were calculated by the life cycle assessment. The potential emission reduction in each region was estimated by combining the GHG emissions and CFs with plantation areas and fruit yields. The results showed that the average GHG emissions in the North China Plain, northwest, and southwest regions were 15,668 kg CO2-eq ha−1, 10,386 kg CO2-eq ha−1, and 5580 kg CO2-eq ha−1, with corresponding CFs of 0.48 kg CO2-eq ha−1, 0.27 kg CO2-eq ha−1, and 0.20 kg CO2-eq kg−1, respectively. The main contribution source of GHG emissions in these three regions was fertilizer (77–95%), followed by electricity, pesticides, and diesel. By adopting advanced farming practices with high yield and a high partial factor productivity of fertilizer, the GHG emissions could be reduced by ~13–35%, with the highest potential reduction in the North China Plain. In conclusion, the GHG emissions and their CFs were impressively high in China’s major peach-producing regions, but these GHG emissions could be substantially decreased by optimizing nutrients and irrigation management, including the rational selection of fertilizer rates and types with water-saving irrigation systems or practices (e.g., mulching) for increasing fertilizer and water use efficiency, and maintaining a sustainable peach production in China or similar countries.

Monitoring of greenhouse gas emissions from farm-scale anaerobic piggery waste-water digesters

AbstractPig manure management systems in Taiwan differ from the model representing the Asian region developed by the Intergovernmental Panel on Climate Change (IPCC). The current study was undertaken to update greenhouse gas (GHG) emission factors of anaerobically treated piggery waste water by operating the conventional three-step piggery waste-water treatment system from selected pig farms located in northern, central and southern Taiwan. Biogas mass flow meters were installed to the outlet of anaerobic basins prior to the biogas pressure stabilizers for direct and reliable biogas measurement. The analytic results showed that average GHG emissions were 0.088, 0.128 and 0.066 m3/head/day in the northern, central and southern pig farms, respectively. Thus, the average emission levels of methane and nitrous oxide were 14.38 and 0.055 kg/head/year, respectively, from anaerobic digestion of piggery waste water for the three pig farms. The average removal efficiency of chemical oxygen demand, biochemical oxygen demand and suspended solids by anaerobic digestion process from the three pig farms was about 77, 93 and 70%, respectively.

Carbon trading, co-pollutants, and environmental equity: Evidence from California's cap-and-trade program (2011-2015).

BackgroundPolicies to mitigate climate change by reducing greenhouse gas (GHG) emissions can yield public health benefits by also reducing emissions of hazardous co-pollutants, such as air toxics and particulate matter. Socioeconomically disadvantaged communities are typically disproportionately exposed to air pollutants, and therefore climate policy could also potentially reduce these environmental inequities. We sought to explore potential social disparities in GHG and co-pollutant emissions under an existing carbon trading program—the dominant approach to GHG regulation in the US and globally.Methods and findingsWe examined the relationship between multiple measures of neighborhood disadvantage and the location of GHG and co-pollutant emissions from facilities regulated under California’s cap-and-trade program—the world’s fourth largest operational carbon trading program. We examined temporal patterns in annual average emissions of GHGs, particulate matter (PM2.5), nitrogen oxides, sulfur oxides, volatile organic compounds, and air toxics before (January 1, 2011–December 31, 2012) and after (January 1, 2013–December 31, 2015) the initiation of carbon trading. We found that facilities regulated under California’s cap-and-trade program are disproportionately located in economically disadvantaged neighborhoods with higher proportions of residents of color, and that the quantities of co-pollutant emissions from these facilities were correlated with GHG emissions through time. Moreover, the majority (52%) of regulated facilities reported higher annual average local (in-state) GHG emissions since the initiation of trading. Neighborhoods that experienced increases in annual average GHG and co-pollutant emissions from regulated facilities nearby after trading began had higher proportions of people of color and poor, less educated, and linguistically isolated residents, compared to neighborhoods that experienced decreases in GHGs. These study results reflect preliminary emissions and social equity patterns of the first 3 years of California’s cap-and-trade program for which data are available. Due to data limitations, this analysis did not assess the emissions and equity implications of GHG reductions from transportation-related emission sources. Future emission patterns may shift, due to changes in industrial production decisions and policy initiatives that further incentivize local GHG and co-pollutant reductions in disadvantaged communities.ConclusionsTo our knowledge, this is the first study to examine social disparities in GHG and co-pollutant emissions under an existing carbon trading program. Our results indicate that, thus far, California’s cap-and-trade program has not yielded improvements in environmental equity with respect to health-damaging co-pollutant emissions. This could change, however, as the cap on GHG emissions is gradually lowered in the future. The incorporation of additional policy and regulatory elements that incentivize more local emission reductions in disadvantaged communities could enhance the local air quality and environmental equity benefits of California’s climate change mitigation efforts.

China's livestock transition: Driving forces, impacts, and consequences.

China's livestock industry has experienced a vast transition during the last three decades, with profound effects on domestic and global food provision, resource use, nitrogen and phosphorus losses, and greenhouse gas (GHG) emissions. We provide a comprehensive analysis of the driving forces around this transition and its national and global consequences. The number of livestock units (LUs) tripled in China in less than 30 years, mainly through the growth of landless industrial livestock production systems and the increase in monogastric livestock (from 62 to 74% of total LUs). Changes were fueled through increases in demand as well as, supply of new breeds, new technology, and government support. Production of animal source protein increased 4.9 times, nitrogen use efficiency at herd level tripled, and average feed use and GHG emissions per gram protein produced decreased by a factor of 2 between 1980 and 2010. In the same period, animal feed imports have increased 49 times, total ammonia and GHG emissions to the atmosphere doubled, and nitrogen losses to watercourses tripled. As a consequence, China's livestock transition has significant global impact. Forecasts for 2050, using the Shared Socio-economic Pathways scenarios, indicate major further changes in livestock production and impacts. On the basis of these possible trajectories, we suggest an alternative transition, which should be implemented by government, processing industries, consumers, and retailers. This new transition is targeted to increase production efficiency and environmental performance at system level, with coupling of crop-livestock production, whole chain manure management, and spatial planning as major components.