Impact of mechanization and previous burning reduction on GHG emissions of sugarcane harvesting operations in Brazil

Concerns about environmental impacts and health effects associated with particulate matter emissions of sugarcane production in Brazil have been raised, mainly due to pre-harvest burning of straw in manual harvesting. In consequence, mechanical harvesting without burning has been increasingly adopted. Life cycle studies have assessed environmental impacts of sugarcane and sugarcane products. However, incorporating health effects of particulate matter 2.5 (PM2.5) in a life cycle assessment focusing on evaluating the impacts of increasing use of mechanization has not been conducted. This article compares the life cycle environmental and health impacts (with spatially differentiated characterization factors for PM2.5) of manual and mechanical harvesting of sugarcane in Brazil, and quantifies the health benefits due to the change of harvesting operations. An attributional life cycle assessment (LCA) of manual versus mechanical sugarcane harvesting was conducted to evaluate the impacts of 1 t of sugarcane at the distillery. ReCiPe was applied to characterize impacts at mid-point (i.e., climate change, fossil depletion, ozone depletion, terrestrial acidification, freshwater eutrophication, human toxicity, photochemical oxidant formation, and particulate matter formation) and end point (i.e., human health, ecosystems, and resources). Impacts on climate change were compared considering different soil carbon sequestration scenarios. Characterization factors (CFs) of health effects of PM2.5 for Brazil were calculated differentiating emission sources, population densities, and burdens of disease. At the mid-point, sugarcane production with manual harvesting has higher impacts on photochemical oxidant formation and particulate matter formation mainly due to pre-harvest burning. Mechanical harvesting system may lead to higher impacts on fossil depletion, ozone depletion, and terrestrial acidification resulting from higher use of fertilizers and diesel. Differences of impacts on climate change between two systems vary depending on the soil carbon sequestration scenario. At the end-point level, manual harvesting has higher impacts on human health but lower impacts on resource use. The health effects of PM2.5 vary considerably with population density. Changing from manual to mechanical harvesting close to urban areas leads to a 93% reduction of health effects, while for rural only 15% and for remote areas 5%. When considering average population density, the health effects of PM2.5 of manual harvesting were approximately six times higher than mechanical harvesting. Health effects of PM2.5 calculated with ReCiPe are much lower and may underestimate the effects of primary PM2.5 emissions. The results of this article are an incentive to accelerate the mechanization of sugarcane harvesting in areas with lower mechanization levels (i.e., north-northeast region in Brazil and some rough terrain areas) concerning public health benefits. Meanwhile, manual harvesting with straw burning should only be performed in fields located in rural or remote areas. These results can also contribute to further studies comparing potential benefits of sugarcane culture with alternative crops and guide better decision making at regional development level. Spatially differentiated CFs of PM2.5 calculated in this article may be applied to future studies regarding health effects in the Brazilian context.

Mechanical sugarcane harvesting increases soil compaction due to the intense traffic of agricultural machinery, reducing longevity of sugarcane crops. In order to mitigate the harmful effects caused by agricultural traffic on the soil structure in sugarcane fields, this study evaluated impacts of mechanical sugarcane harvesting on traffic lane under two soil tillage systems based on load bearing capacity models. The experiment was carried out in the region of Piracicaba, state of Sao Paulo, Brazil, on a Rhodic Nitisol, under conventional tillage (CT) and deep strip-tillage (DST). For CT soil tillage was applied to the entire area with a heavy disk harrow, at operating depths from 0.20 to 0.30 m followed by a leveling harrow at a depth of 0.15 m. For DST, soil tillage was performed in part of the area at a depth of 0.80 m, forming strip beds for sugarcane planting, while the traffic lanes were not disturbed. Undisturbed soil samples from traffic lanes were used in the uniaxial compression test to quantify preconsolidation pressure and to model the soil load bearing capacity. The surface layer (0.00-0.10 m) was most susceptible to compaction, regardless of the tillage system (CT or DST) used. In the DST, the traffic lane maintained the previous soil stress history and presented higher load bearing capacity (LBC) than the traffic lane in the CT. As in CT the soil was tilled, the stress history was discontinued. This larger LBC in DTS minimized the impacts of the sugarcane harvest. Under CT, additional soil compaction due to mechanical sugarcane harvesting in the traffic lane was observed after the second sugarcane harvest. There was a reduction in load bearing capacity from 165 kPa to 68 kPa under CT and from 230 kPa to 108 kPa under DST, from the first to the second harvest at surface layer. Water content at mechanical harvesting was the most relevant factor to maximize impacts on the soil structure in traffic lanes, for both tillage systems.

Possible impact of the Renewable Energy Directive on N fertilization intensity and yield of winter oilseed rape in different cropping systems

Robust multi-criteria weighting in comparative LCA and S-LCA: A case study of sugarcane production in Brazil

Greenhouse gas emissions from electricity generated by offshore wind farms

Environmental impacts concerning flexible power generation in a biogas production

An assessment of mechanical vs manual harvesting of the sugarcane in Sudan – The case of Sennar Sugar Factory

A methodology for estimating specific (per unit of transport work) greenhouse gas emissions by traffic flows on certain sections of the road network is presented and its approbation is carried out. The main factors for reducing specific (per unit of transport work) greenhouse gases (GHG) emissions by traffic flows when considering different sections of the road network, provided that the composition of the traffic flow by type of vehicle, type of fuel (energy) used and environmental class of the vehicle, passenger capacity and carrying capacity of specific vehicles does not change, is the length of the road network section, the number of traffic lanes, the average speed and traffic intensity, which are affected by the presence of public transport routes on them, traffic light regulation. Reduction of specific greenhouse gases (GHG) emissions by traffic flows on sections of the road network in the foreseeable future will be achieved by increasing the share of electric vehicles powered by traction batteries and fuel cells powered by hydrogen in the vehicle traffic flow. It is expected that in the composition of traffic flows on the road network in 2054 there will be 20% of such vehicles in the composition of cars, trucks - about 10% and buses - 30%.

An assessment of harvesting practices of sugarcane in the central region of Thailand

Microbial communities play a critical role in peatland ecosystems, and in determining whether they act as net sinks or sources of greenhouse gas (GHG) emissions to the atmosphere. Furthermore, microbial community composition responds to changes in water table and physicochemical conditions, which are also determinants of GHG emissions from peatlands. Land management practices can significantly impact the water table and soil physicochemical conditions, influencing soil microbial community composition and activity, and site specific GHG emissions. Our study aimed to elucidate the role of paludiculture (peat conserving land use) intensity and nitrogen concentration on microbial community composition and function, and in turn, the potential role of changing microbial communities on seasonal GHG emission dynamics. We investigated GHG emissions, as well as a range of site physicochemical parameters, from 14 different EU fen peatlands, located in Germany (6), Netherlands (4) and Poland (4), on a monthly basis over the course of two years. Additionally, seasonal peat samples over two depths (living surface or 0cm, and at ~ 15cm depth below surface) were analysed for microbial community composition and function. Sample sites were separated into two different categories: Typha sp. dominated sites (7 sites, assumed to be highly nitrogen contaminated) and Carex sp. dominated (7 sites, assumed to be moderately Nitrogen contaminated) sites, with each further separated into three different paludiculture intensities: Wet wilderness (6 sites), Low intensity Paludiculture (6 sites) and High intensity paludiculture (2 sites). Initial results suggest a close relationship between microbial community composition and the sample country, as well as hydrological and nutrient status of the site, with a potentially significant relationship between microbial community composition, their main functions, and specific GHG emissions. The findings of our study would help to better understand how different paludiculture practices may impact microbial communities and influence GHG emissions from differently managed paludiculture sites.

<p>Aquifer Thermal Energy Storage (ATES) is an open-loop geothermal system enabling seasonal storage of thermal energy in groundwater. It is a promising technology for environmentally friendly energy generation that can overcome the seasonal mismatch between demand and supply of heating and cooling and helps to reduce greenhouse gas (GHG) emissions. Yet, there are only few studies quantifying GHG emissions caused by ATES systems over their entire life cycle. This study presents a novel life cycle assessment (LCA) regression model focusing on the GHG emissions that is a fast alternative to conventional time-consuming LCA. Due to its parametric structure, the regression LCA model can be used to perform Monte Carlo simulations of a wide range of different ATES configurations. Accordingly, it allows the environmental evaluation of the technology as a whole.</p><p>The application of the model reveals that the median value of investigated ATES configurations is 83.2 gCO<sub>2eq</sub>/kWh<sub>th</sub> with most of the emissions resulting from electricity consumption during the operational phase. Compared to conventional heating systems based on heating oil and natural gas, this value reveals potential GHG savings of up to 74 %. In terms of cooling, ATES can save up to about 59 % of GHG emissions compared to conventional, electricity-based technologies. Specific GHG emissions from a modified LCA regression model considering a projected electricity mix for the year 2050 add up to 10.5 gCO<sub>2eq</sub>/kWh<sub>th</sub> forecasting even higher emission savings of up to 97 %. A sensitivity analysis reveals that in particular the operational time for cooling and the coefficient of performance (COP) of the heat pump should be carefully considered when planning or optimizing new systems under current conditions. In contrast, when considering the projected 2050 electricity mix, the most important system parameter is the number of wells. This reflects the decreasing importance of the electrical power necessary for ATES operation due to the much lower specific GHG emissions of the projected 2050 electricity mix.</p>

Environmental issues in energy policy, especially global warming, have received more attention lately than ever before. Excessive dependence on fossil fuels, deforestation, and land degradation are the three main factors that lead to increased carbon dioxide (CO2) emissions. Consequently, the global average temperature has doubled compared to anticipation. Various international protocols and agendas have been established, pledged to restore the global average temperature to the 1990 level. As a result, energy policies worldwide have also undergone various transformations to align with these protocols since then. As a developing nation, Malaysian’s electricity demand has continuously grown in the past two decades. To date, the electricity sector is still dominated by fossil fuels. Government incentives have been the most influential factor in the nation’s energy mix trend. Several energy policies implemented throughout the past 22 years have seen the shift from natural gas to coal power in power plants, and in more recent years, renewable energy resources. Numerous studies in the past have independently outlined the status of various energy source in Malaysia. However, they all fell short in providing the greenhouse gas (GHG) emissions in the Malaysian energy sector. Notably, the question that remains to be answered is how GHG emissions have changed in response to the amendment in the energy mix; hence, the effectiveness of policy change in this aspect remains unknown. This paper analysed the past and present trend of Malaysia electricity generation mix and the resultant GHG emissions. In particular, this paper focused on investigating the variation of combined specific GHG emissions in the Malaysian electricity sector, in response to the policy change within the past 22 years. This provides the insight for Malaysian policymakers to evaluate the effectiveness of past policies in GHG emissions and the measures to be taken in future. The finding of this paper shows the attention on the nation’s GHG emissions has evolved over the years, following the diversification in energy mix driven by the policy change. It was also found that, on average, it took a decade for a significant reduction in specific GHG emission to be visible since the government’s energy policy implementation.

Water and energy use and greenhouse gas emissions for nixtamalised maize masa flour production

A mudança na dinâmica de trabalho no processo de colheita da cana-de-açúcar, através da crescente mecanização, tem submetido os trabalhadores a novas condições de trabalho, que inclui a interação com máquinas e equipamentos, alterando o perfil das doenças e acidentes de trabalho. Uma das formas de solucionar os problemas resultantes das condições de trabalho transformadas pela mecanização é através da utilização de instrumentos que permitam a identificação de riscos provenientes da relação homem-trabalho. Este estudo objetivou selecionar os pontos de verificação aplicáveis ao processo de colheita mecanizada da cana-de-açúcar, a partir do instrumento Ergonomic Checkpoints in Agriculture. Foi feita uma revisão bibliográfica das etapas do processo de colheita mecanizada da cana-de-açúcar, e considerando suas particularidades, foram analisados e selecionados os pontos descritos no instrumento. Como resultado, foram identificados trinta e quatro pontos de verificação com potencial de aplicação no processo de colheita mecanizada da cana-de-açúcar.

Hydroponic system and desalinated seawater as an alternative farm-productive proposal in water scarcity areas: Energy and greenhouse gas emissions analysis of lettuce production in southeast Spain