Environmental Impact Indicators Research Articles

Benthic foraminifera as an environmental proxy for pollutants along the coast of Chennai, India

Benthic foraminifera are increasingly used as an indicator of environmental disturbance. Their sensitivities to pollutants can be reflected by changes in assemblage, which can provide useful information about ecosystem health. This study aimed to investigate the impact of organic and inorganic pollutants on the benthic ecology of the Chennai coast, with a focus on the 2017 oil spill caused by the collision of two ships. Sediment samples collected from five distinct zones along the coast were analysed for pollutants such as polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPH), heavy metals (Cr, Cd, Pb) and total organic carbon (TOC). The maximum concentrations of Cr (137 μg/g), Cd (6.93 μg/g) and Pb (34.2 μg/g), as well as TPH (84.3 μg/g) and PAHs (227 ng/g), were observed. A total of 47 species of foraminifera were identified in this study, of which 12 were morphologically abnormal. In the low-impact zone, the species diversity index (H′) was higher. TPH and PAH concentrations were positively associated with abnormal species. Pollution-resistant foraminifera species include Ammonia tepida, Elphidium discoidale, and Quinqueloculina lamarckiana, while opportunistic foraminifera include Pararotalia curryi, Nonionella stella, Rosalina globularis, and Spirillina vivipara. PAHs and heavy metals were adversely correlated with foraminiferal abundance, while TPH was positively correlated. To assess the response of the benthic ecosystem to hydrocarbon pollution, indices such as the Foraminiferal Index of Environmental Impact (FIEI), Exponential (H′bc) index and the Foraminiferal Abnormality Index (FAI) were used as environmental health proxies. FIEI, exp(H′bc) and FAI values show the impact of hydrocarbon pollution to an extent along the northern Chennai coast.

Global warming potential-based life cycle assessment and optimization of the compressive strength of fly ash-silica fume concrete; environmental impact consideration

In this research study, extensive literature searches on the compressive strength of concrete produced from the addition of fly ash (FA) and silica fume (SF) as extra constituents to the conventional concrete mixes, which gave rise to 330 mix points of concrete database. Due to the worrisome environmental impact of concrete production and usage in concrete activities, it has been pertinent to conduct the life cycle impact assessment of this procedure. Secondly, due to the over dependence of concrete production experts on laboratory exercise, there is also an urgent need to propose equations that reduce this dependence, that can be used in design, construction and performance evaluation of concrete infrastructure, hence the multi-objective nature of this research work. The results of the global warming potential (GWP) based on cement dosage show that Portland cement contributes about 90% of the total score. This is followed by the use of coarse aggregate contributing 6%, superplasticizer, 3% and fine aggregates, 2%. These show the functions of CO2 emissions and other greenhouses gas emissions in the entire system. Also, the result of the terrestrial acidification potential (TAP) for the concrete mixes in this study show that the lowest cement mix “C340-FAg658-FA0-SF15ˮ has a human toxicity, both carcinogenic and non-carcinogenic that showed an added impact of about 14 kg of 1, 4 equivalents of dichlorobenzene (DCB eq.). This result is 428% less impact than other studies found in the literature that used FA. Finally, it was found that the addition of FA and SF in concrete has a lowering effect on the environmental impact indicators due to reduced cement dosage. Furthermore, the results of the model predictions show that ANN with a performance index of 0.986 (4.8%) showed decisive superiority to predict the compressive strength of the FA-SF concrete over EPR, 0.951 (8.7%), GP, 0.94 (9.5%) and GEP, 0.93 (10%).

Orta ve Küçük Ölçekli Rüzgar Türbinlerinin Yaşam Döngüsü Boyutunda Sürdürülebilirliği: Literatür Taraması

With the growing interest in renewable energy systems, studies on the sustainability of small-scale wind turbines have been published in recent years. A literature review was conducted in this study to compile scientific studies conducted to evaluate the environmental effects of medium and small-sized wind energy systems using the life cycle assessment. Life cycle assessment is a method of evaluating the environmental sustainability of a product, process, or system that is becoming more important in the context of decisions and policies in the energy sector. The environmental effects of medium and small-sized wind turbines on the life cycle size have been investigated in this study, which looked at studies conducted since 2004. The vast majority of these studies conducted environmental sustainability assessments based solely on a few environmental impact indicators such as global warming potential. There are only a few studies that consider a wider range of environmental effects. The collection and analysis of studies examining the life cycle environmental sustainability of medium and small-scale wind turbines are important for determining the future vision of small-scale energy production systems.

Comparative well-to-pump assessment of fueling pathways for zero-carbon transportation in China: Hydrogen economy or methanol economy?

Decarbonization of the fuel sector is crucial to achieving a zero-carbon economy. Both hydrogen and methanol are promising solutions to contribute to this goal. Herein, a comprehensive well-to-pump (WTP) energetic, environmental and economic (3E) assessment for various methanol and hydrogen production pathways is conducted based on the GREET software and data for China. Energy efficiency, levelized cost of fuel, direct and indirect emission, as well as other midpoint environmental impact indicators are compared. The gaseous and liquid hydrogen are produced from coal gasification (CGT), coal coking (CCT), natural gas reforming, and alkaline water electrolysis by renewable and grid electricity. Methanol production pathways include CGT, CCT and CO2 hydrogenation. The results indicate that most methanol produced from CO2 hydrogenation as well as green H2 yield environmental benefits but also entail energy efficiency loss. Specifically, compared to conventional methanol, hydrogen and green hydrogen, the environmental benefits increase by up to 101%, 103% and 104%, whereas the energy efficiency drops by up to 71%, 75% and 85%, respectively. With current technology, the levelized costs of methanol production can be between 12% and 75% lower than most hydrogen production pathways. Compared to hydrogen supply chain, the levelized cost of methanol supply is primarily concentrated in the production stage (67%∼93%). In general, although hydrogen can be an important carbon emission free fuel in the long run, methanol produced from CO2 hydrogenation assisted by renewable sources is the most feasible near-term pathway in China, offering an easier to market carbon neutral fuel source.

A Risk-Based Analysis Approach to Sustainable Construction by Environmental Impacts

Sustainable construction is a comprehensive process of balancing the natural and built environment by applying sustainable development concepts. The golden triangle in the construction of time, cost, and quality should also assess risks from a sustainable perspective and investigate the environmental dimensions of the project. However, proper risk assessment for green sustainability is challenging, resulting in project management conducted under uncertain conditions. This study proposes a procedure based on Monte Carlo Simulations to improve the assessment of critical risk factors associated with construction activities. The AHP method was applied to rank environmental impact indicators, and the EMV approach was used to calculate the effects of the expected outcomes. The current study shows that air, water, and land pollution, water consumption, and solid waste are the most critical indicators. The results indicate that the equipment breakdown significantly impacted the duration of (and increase in) environmental issues. The evidence suggests that attention should be paid to sustainability risk factors during construction activities, e.g., the unavailability of materials had the most significant impact on the cost of the construction phase. The results suggest that the inadequate control of sustainability risk factors can lead to poor performance and tough decisions in a construction project.

Evaluation of Urban Green Building Design Schemes to Achieve Sustainability Based on the Projection Pursuit Model Optimized by the Atomic Orbital Search

The popularization and use of green buildings are of great significance for reducing the carbon emissions of buildings and achieving sustainable development. Scientific evaluation of the green building design scheme is the key factor in ensuring the popularization and use of green buildings. To overcome the shortage of a systematic evaluation index system and comprehensive evaluation method, an evaluation index system of green building design schemes and an evaluation method based on the projection pursuit model were developed. First, according to the needs of green building development, an evaluation index system of green building design schemes was systematically constructed from the five aspects of the economy, the resource utilization index, environmental impacts, technical management, and social impacts. The calculation methods of all secondary indexes are provided in detail. Then, a novel evaluation method based on the projection pursuit model optimized by the atomic orbital search was constructed. This method searches for key influencing factors and determines the evaluation grade from the evaluation data structure, and realizes the scientific and objective evaluations of green building design schemes. Finally, the Nanchang Hengda Project was selected to conduct a detailed empirical study. The research results show that the incremental net present value of the investment, the energy consumption of the air conditioning system, and the ratio of the window area to the indoor area are the most important secondary indexes. Moreover, the environmental impact index was found to be the most important primary index. Via comparisons with different optimization algorithms and evaluation methods, the superiority of the proposed model is proven.

Improvement of quarry and slagheap reclamation technology

This paper considers and analyzes a relevant issue of treatment of disturbed soils. The equipment to carry out various processes of mining reclamation of waste heaps and quarries with a significant reduction in the level of environmental risks through the operation of an energy-saving small-sized apparatus has been designed. The use of the developed soil reclamator is also adequate for pre-sowing and other types of agrotechnical tillage, plant care in agricultural fields, as well as in areas with a heterogeneous landscape. The functionality of the unit is able to provide energy autonomy and automation of the technological process. The low weight of the device makes it possible to reduce the pressure on the soil, which minimizes the environmentally hazardous formation of dust during the treatment of waste heaps, the destruction of its structure, the machine degradation of the fertile layer during the processing of all types of territories. The device also reduces the risk of fertile soils slipping from the slopes of mine dumps due to the fact that the soil reclamator is self-propelled and functions without the need to involve a heavy tractor. The mathematical modeling of the operation of the proposed technical support for the treatment of waste heap reclamation in comparison with the opposed analog proves the ecological and economic efficiency of the eco-adaptive soil reclamator. The average value of profit ratios, when using the proposed soil reclamator, is 121.82 % higher than with the involvement of opposed equipment. Indicators of the negative environmental impact of the designed equipment are 100 % lower than the environmental impact when operating the analog. The proposed technical solution can be effectively applied both in schemes of sanitary cleaning of settlements, and in the process of modernization of agricultural machinery

An efficient approach for sustainable fly ash geopolymer by coupled activation of wet-milling mechanical force and calcium hydroxide

Geopolymer is a potential substitute for high-emission cement production. Therefore, the use of fly ash with high emission as a geopolymer is an environmentally friendly and inexpensive direction. However, fly ash (FA) is a high amorphous precursor with low pozzolanic reactivity making it difficult to be activated by calcium hydroxide. In this study, the coupling of wet-milling mechanical force and calcium hydroxide was used to prepare high-performance alkaline calcium activated geopolymers. Two kinds of FA slurries with different particle sizes of D50 = 2.96 μm and 14.2 μm were prepared, activated by calcium hydroxide (CH) with the content of 4%, 11% and 19%. Results indicated that the increase of calcium hydroxide content was beneficial to developing strength, effectively improving the chloride resistance, compacting the microstructure, but increasing the autogenous shrinkage of the geopolymers. These improvements are especially apparent in the wet-milled fly ash geopolymers (WFA) due to the pre-depolymerization implemented by wet-milled mechanical forces, and coupled with the activation effect of CH to improve the depolymerization efficiency and condensation reaction. The compressive strength of WF-CH-19 was three times higher than that of FA-CH-19, reaching 29.3 MPa at 28 d, and the compressive strength growth of WF-CH-11 even reached 591.67% at 1 d. Meanwhile, the main chain length (MCL) and Al/Si of calcium silicate hydrates were clearly improved, and pore structure was significantly refined with capillary pore increased from 29.79% to 89.23%. In addition, FA and WFA geopolymers have significant advantages over Portland cement in the environmental impact indicators such as E-energy and E-CO2.

Study on the water-richness law and zoning assessment of mine water-bearing aquifers based on sedimentary characteristics

To study and prevent the water hazards of deep coal mines roof in the Inner Mongolia–Shaanxi (IM–S) mining area, it is essential to correctly evaluate the water-richness distributions of water-bearing aquifers in roof. This paper puts forward a sediment control method for water-richness law and zoning in the roof aquifers of deep Jurassic coals. To determine the vertical distance of direct water-bearing aquifers, the height of fractured water-conducting zone was detected by an underground network parallel electrical method. The plane and lateral spatial distribution patterns of the water-bearing aquifers and the control of the water-richness distribution was analyzed with the sediment control method. An evaluation system that consisted of four indicators, i.e., sedimentary environmental impact index, interlayer ratio of sandstone and mudstone, sandstone thickness, geophysical water-richness anomaly index was constructed. Furthermore, an Analytic Hierarchy Process (AHP) was introduced to establish the comprehensive zoning map. Finally, through the example analysis of Muduchaideng coal mine, the zoning evaluation results of water-richness were verified by the mine inflow. The findings of this study provide scientific guidance for prevention and control of mine water hazards in the IM–S mining area.

Embodied energy and carbon emissions analysis of geosynthetic reinforced soil structures

The significant role of geotechnical engineering in achieving sustainable development is often neglected. Geosynthetic reinforced soil (GRS) technology brings promising prospects for embracing sustainable practices. In this study, the embodied energy (EE) and embodied carbon (EC) of three design options for a hypothetical large retaining structure project in China are investigated. The purposes are (1) to capture the relative impact contributions of the process stages in each design; (2) to determine whether GRS technology has significant merits regarding environmental impact among various structures; (3) to understand the distribution characteristics of the environmental impact indicators of the collected materials; and (4) to compare the difference in environmental impacts caused by geographical factors of carbon coefficient (CC). Results show that the stage of raw material production for various design options has the greatest impact on the environment. GRS technology could reduce the total embodied energy (TEE) and TEC of large retaining structures by an average of 30% and 60%, respectively. The embodied energy coefficient (EEC) and CC values of geosynthetics exhibit significant variety. Recycled steel can drastically reduce its impact on the environment. The results of the assessment can be affected by the spatial variability of CC, but its influence is limited.

Evaluation of Economic Benefits and Ecological Environment Impact of Export Trade in Anhui Free Trade Zone

Nowadays, the scale of international trade is expanding at a great pace, leading to the development of the economy of different countries. Global industrialization and urbanization are developing with each passing day, and this fast economic expansion is putting a tremendous impact on the environment. Like the other countries, the scale of Chinese export trade is also increasing with time, resulting in the stable economy of our country. With the improvement of living standards, people are continuously demanding high environmental facilities. Further, the impact of trade (enterprises, companies, industries, etc.) on the ecological environment has become a worldwide problem because economic progress brought forth by trade expansion may directly affect the environment by causing pollution to rise or the degradation of natural resources. This indeed is a serious issue; therefore, various countries have started focusing on the impact of export trade on the ecological environment. In recent years, the issue of economic benefits and the environmental impact of export trade has become a hot topic of research. Therefore, this study focuses on the relationship between trade, economy, and environmental quality in China. For the accomplishment of our research study, we selected Anhui free trade zone (FTZ) as an example to analyze the interaction between the economic benefits of Anhui export trade and the local environment. It is among the top trading provinces in China having a faster economic development. In order to accurately study the economic benefits and environmental impact of export trade in the Anhui FTZ, this paper selects industrial waste gas, wastewater, and solid waste to establish an export trade environmental impact indicating system. After comparative analysis, three factors that include industrial soot (dust) emissions for export trade, chemical oxygen demand for trade, and general industrial solid waste dumping and discards are selected to evaluate the impact on the environment of the free trade zone. Based on this, the export trade environment vector autoregressive (VAR) model is established, and the variance decomposition method is used to analyze the dynamic impact of various factors on the environmental impact index. Further, we established an economic benefit VAR model based on the export economic benefit index (EI), export value (EV), and export product concentration (EPC) index and judged the economic benefit of the Anhui free trade zone based on the contribution rate of the obtained three factors. The experimental results show that the export volume and product concentration directly affect the economic benefits of the region, and at the same time, the expansion of export trade promotes the growth of economic benefits.

Multi-Objective Prediction of the Mechanical Properties and Environmental Impact Appraisals of Self-Healing Concrete for Sustainable Structures

As the most commonly used construction material, concrete produces extreme amounts of carbon dioxide (CO2) yearly. For this resulting environmental impact on our planet, supplementary materials are being studied daily for their potentials to replace concrete constituents responsible for the environmental damage caused by the use of concrete. Therefore, the production of bio-concrete has been studied by utilizing the environmental and structural benefit of the bacteria, Bacillus subtilis, in concrete. This bio-concrete is known as self-healing concrete (SHC) due to its potential to trigger biochemical processes which heal cracks, reduce porosity, and improve strength of concrete throughout its life span. In this research paper, the life cycle assessment (LCA) based on the environmental impact indices of global warming potential, terrestrial acidification, terrestrial eco-toxicity, freshwater eco-toxicity, marine eco-toxicity, human carcinogenic toxicity, and human non-carcinogenic toxicity of SHC produced with Bacillus subtilis has been evaluated. Secondly, predictive models for the mechanical properties of the concrete, which included compressive (Fc), splitting tensile (Ft), and flexural (Ff) strengths and slump (S), have been studied by using artificial intelligence techniques. The results of the LCA conducted on the multiple data of Bacillus subtilis-based SHC mixes show that the global warming potential of SHC-350 mix (350 kg cement mix) is 18% less pollutant than self-healing geopolymer concrete referred to in the literature study. The more impactful mix in the present study has about 6% more CO2 emissions. In the terrestrial acidification index, the present study shows a 69–75% reduction compared to the literature. The results of the predictive models show that ANN outclassed GEP and EPR in the prediction of Fc, Ft, Ff, and S with minimal error and overall performance.

Analysis of Energy and Environmental Indicators for Sustainable Operation of Mexican Hotels in Tropical Climate Aided by Artificial Intelligence

This study assessed the energy-use index and carbon-footprint performance of nine medium-category Mexican hotels (two–four stars) located in tropical-climate regions. The consumption of electrical and thermal energies of each hotel was collected during audits. Based on this, various scenarios of the partial replacement of the most energy-consuming devices were evaluated and synthesized in an expert model based on artificial neural networks. The artificial-intelligence model was designed to simultaneously associate the energy-consumption indicators, environmental impact, and economic savings of hotels based on their category, location, room number, number of existing electrical or thermal devices, and their percentage of substitution with more energy-efficient technologies. The model was used to compare the various partial-technology-substitution alternatives in each hotel that could reduce energy consumption and CO2 emissions based on the current values reported by the energy-use and environmental-impact indicators. The results of the proposed approach showed that even without making total replacements of equipment such as interior and exterior lighting or air conditioners, it was possible to identify configurations that could reduce the hotels’ energy use per room-year by 9–12%. In the environmental case, using more efficient technologies could reduce environmental mitigation. The proposed methodology represents an attractive option to facilitate the analyses and the decision making of administrators according to the needs of the type of hotel to improve its performance, which also affects the reduction in operating costs.

A life cycle assessment of Hydropower-Silicon-Photovoltaic industrial chain in China

In this paper, we conducted a life cycle assessment (LCA) for the Hydropower-Silicon-Photovoltaic (HSPV) industrial chain in China. The Energy Conservation and Emission Reduction Index in the 13th Five Year Plan of China (ECER-135) is calculated based on the software eBalancev4.7 (eB) and eFootprint (eF). The total environmental impact index of ECER-135 of the HSPV industrial chain is 2.61E-06. The uncertainty result of the comprehensive index is 15.21% and the uncertainty of the inventory data is no more than 30%. The Energy Payback Time (EPBT) of the HSPV industrial chain is calculated as 1.68 years, accounting for only 5.60% of the operating cycle of the PV station. There are 7 impact category indexes of ECER-135, which are Chemical Oxygen Demand (COD), Primary Energy Demand (PED), CO2, SO2, Ammonia Nitrogen Content (NH3–N), NOx and Industrial Water Use (IWU). Considering the contribution of characteristic indexes to ECER-135, the contribution of PED index accounts for 22.93% of ECER-135, which is the major factor to environmental impact, and it is followed by COD, which accounts for 18.40%. Considering the contribution of each stage to ECER-135, PV module manufacturing, BOS manufacturing and SoG-Si manufacturing stages have significantly contributed to ECER-135, in which the PV module manufacturing stage has the greatest contribution to ECER-135, accounting for 97.63%, which is the main stage of impact on the environment. The sensitivity analysis reveals that the highest sensitivity is copper wire consumption, which is 47.83%. It is followed by aluminum consumption during the BOS manufacturing and the PV module manufacturing, which are 41.70% and 29.75% respectively. Finally, compared the total environmental impact of the HSPV industrial chain and the Thermalpower-Silicon-Photovoltaic (TSPV) industrial chain, the results reveal that the HSPV industrial chain has the energy-saving and emission reduction benefits of 2.89E-06, whose comprehensive indexes account for 47.39% of that of the TSPV industrial chain, proving that the HSPV industrial chain has significant energy saving and emission reduction benefits in all indexes. The EPBT of the HSPV industrial chain is only 38.17% of that of the TSPV industrial chain.

ENVIRONMENTAL IMPACTS OF COMMUNITARY CROPS OF SWEET QUINOA (CHENOPODIUM QUINOA WILLD. VAR. TUKAHUAN) AT ANDEAN REGION IN ECUADOR

Quinoa (Chenopodium Quinoa) is a trendsetter crop as it is a great source of vitamins, proteins and minerals and it is a gluten-free pseudocereal. Agriculture is a sector that contributes to climate change through greenhouse gas emissions. In Ecuador, agriculture contributed to 18.03% of emissions. The purpose of this research was to determine the Life Cycle Analysis (LCA) of communitarian systems that produce Sweet Quinoa in Ecuador. It was carried out by an inventory of the LCA. The data collected were through interviews and surveys, chemical analysis of soil samples, plant structure and manure applied. A bag of 25 kg of Quinoa has been selected as a functional unit. Impact indicators were defined as Quinoa yield per single environmental impact index, including GWP, aquatic eutrophication potential and aquatic ecotoxicology. The results indicate that a Quinoa yield obtained by a suitable application of manure is lower or equal to Wheat. The mitigation of aquatic eutrophication caused by the excessive use of N-fertilizer is an important factor in improving the eco-efficiency of the Quinoa productive chain. The importance of the LCA of an agro-product lies in knowing and reducing different environmental impacts and encouraging sustainable production.

Comparative Life Cycle Assessment of Hardmetal Chemical Recycling Routes

Secondary hardmetal is a large part of the supply for new hardmetal products, yet the environmental impacts of hardmetal recycling remain unknown to a large degree. The goal of this study was to evaluate the gate-to-gate impacts of tungsten and cobalt recovery by chemical recycling. The LCI data was obtained from process simulations and the environmental impact categories were calculated using GaBi software. The simulations were used to study process performance and to investigate the effect of process parameter variation on the environmental impact indicators. Compared to primary production, chemical recycling decreased impacts by more than 50% in all investigated impact categories. The global warming potential for treating 1 metric ton of hardmetal scrap by standard chemical recycling to APT and Co(OH)2 was 6121 kg CO2-eq., freshwater consumption 142 m3, eutrophication potential 2.3 kg P-eq., ozone depletion potential 0.0030 kg CFC-11-eq., acidification potential 91 kg SO2-eq., and photochemical ozone formation potential 11 kg NOx-eq. Process hotspots depended on the impact category of interest, but in most cases included oxidation of the scrap material and APT production. Major contributors to environmental impacts included electricity consumption, leaching chemicals, and heating required by the oxidation.

The LCT Challenge: Defining New Design Objectives to Increase the Sustainability of Building Retrofit Interventions

The decarbonization of the construction sector, which is one of the most impactful sectors worldwide, requires a significant paradigm shift from a linear economy to a circular, future-proofed and sustainable economy. In this transition, the role of designers and structural engineers becomes pivotal, and new design objectives and principles inspired by Life Cycle Thinking (LCT) should be defined and included from the early stages of the design process to allow for a truly sustainable renovation of the built environment. In this paper, an overview of LCT-based objectives and principles is provided, critically analyzing the current state of the art of sustainability and circularity in the construction sector. The effectiveness of applying such design principles from the early stages of the design of retrofit interventions is then demonstrated with reference to a case study building. Four seismic retrofit alternatives made of timber, steel and concrete, conceived according to either LCT principles or traditional, were designed and compared to a demolition and reconstruction scenario on the basis of five common environmental impact indicators. The indicators were calculated adopting simplified LCA analyses based on Environmental Product Declarations (EPDs), considering the product and End of Life stages of the building. The results of the comparative analyses confirm that LCT-based retrofit solutions are less impactful than both the traditional seismic retrofit interventions and the demolition and reconstruction scenario.

Research on the Eco-Efficiency of Rice Production and Its Improvement Path: A Case Study from China.

The eco-efficiency of rice production is an important indicator in the measurement of sustainable rice development. Scientific evaluation of the eco-efficiency of rice production facilitates accurate evaluation of the real level of rice ecosystems to realize efficient utilization of agricultural resources. This paper measured the eco-efficiency of farms growing rice using both the life cycle assessment (LCA) and the data envelopment analysis (DEA) methods based on survey data from 370 farms mainly growing rice conducted in 2020 in the Hubei Province, the middle reaches of the Yangtze River in China. Then, sensitivity analysis and scenario analysis were carried out on the comprehensive index of the rice environmental impact and eco-efficiency of rice production, respectively. The results indicate that the comprehensive index of the rice environmental impact was 2.0971. Water toxicity, soil toxicity and eutrophication were the main influencing factors. The mean value of the eco-efficiency reached 0.51. More specifically, the proportion of farms in the low-, middle- and high-efficiency groups was 87.03%, 1.89% and 11.08%, respectively, with mean values up to 0.42, 0.86 and 1.14, respectively. A sensitivity analysis revealed that the pesticide sensitivity was higher than the fertilizer sensitivity in terms of the environmental impact sensitivity of rice systems. When comprehensively considering environmental and economic benefits, the fertilizer sensitivity was higher than that of pesticides. Moreover, reducing the application of both fertilizers and pesticides by 50% could promote the eco-efficiency of rice production systems by 6%, and the value could reach 0.54. Thus, reducing the application of fertilizers and pesticides and improving the utilization efficiency are effective ways to improve green rice production.

METHODOLOGICAL BASES FOR ASSESSING THE ENVIRONMENTAL IMPACT FROM THE INTRODUCTION OF A FREQUENCY-CONTROLLED ELECTRIC DRIVE AT PUMPING STATIONS OF WATER SUPPLY AND SEWERAGE SYSTEMS

A methodology for determining the environmental impact indicators from the operation of centrifugal pumps of water supply and distribution systems (WSDS) and wastewater pumping systems (WPS) is presented. The main dependences are given that allow calculating the cost of standard fuel for the process of pumping water and wastewater and the level of greenhouse gas emissions in CO2 equivalent. The dependences of determining the level of leaks due to the excess of the calculated pressure in the water distribution system are also given. Recommendations are given for the practical application of the methodology in the implementation of energy-saving and environmental measures at the pumping stations of the WSDS and WPS.

Environmental impact assessments of different auxiliary power units used for commercial aircraft by using global warming potential approach.

In this paper, environmental impact analysis is applied to the various auxiliary power units (APUs) used for commercial aircraft in air transportation sector. The exhaust emissions of different auxiliary power units used in commercial aircraft are investigated. The emission index (EI), global warming potential (GWP) rate, global warming potential index (GWPI), environmental impact (EnI) rate, environmental impact index (EnII), environmental damage cost (EDC) rate, and environmental damage cost index (EDCI) of the exhaust emissions of APUs are computed. The GTCP36-300 model APU has the lowest total emission rate (TER) with 1.333kg/h, the GTC85-129 model APU has the maximum total environmental index (TEI) by 24.719g/kg-fuel, the GTCP36-300 model APU has the best total global warming potential value with 2709.176kg/h CO2_eqv, the TSCP700 model APU has the worst global warming potential index rate as 52.481kg/kWh CO2_eqv, the best total environmental damage cost rate is calculated to be 3.717 €/h for GTC85-72 model APU, the TSCP700 model APU has the highest environmental damage cost index with 0.130 €/kWh, the maximum total environmental impact is computed to be 5656.378 mPts/h for GTCP660 model APU, and the best total environmental impact index is determined for the GTC85-72 model APU.