Your search

This study explores how to effectively evaluate the efficiency of environmental education (EE) among college students in Guangdong Province by comparing two complementary methods: (1) traditional statistical analysis of structured questionnaires using chi-square tests, and (2) semantic network analysis (SNA) of open-ended responses. The structured questionnaire assessed students' environmental knowledge, attitudes, behaviors, and education needs using multiple-choice and Likert-scale items. An open-ended question was included to capture students’ understanding of ""environmental protection"" in their own words, which was then analyzed through semantic network modeling. The study collected 225 valid responses from students at Guangdong University of Science and Technology. Chi-square tests revealed significant differences between first-year students and those in later years in their knowledge of environmental issues (e.g., χ², p < 0.05 across 35 indicators), but no significant differences were observed based on gender or place of residence. Semantic network analysis, using centrality, density, and clustering coefficients, showed similar cognitive divergences between academic years but confirmed no meaningful structural differences in conceptual associations across gender or residence groups. For instance, the semantic network of first-year students had lower density (0.031) and fewer central nodes than that of senior students, indicating a simpler understanding of environmental concepts. The convergence of results from both methods validates the use of semantic network analysis as a complementary, quantitative tool for evaluating students’ cognitive structures and discourse in environmental education. This integrated approach offers a richer and more nuanced perspective than traditional surveys alone. The findings suggest that environmental education efforts should focus more on advancing conceptual depth as students progress through university. Curriculum designers can use semantic analysis as an innovative diagnostic tool to improve the cognitive and discourse-based effectiveness of environmental education programs.

The pervasive presence of microplastics in the environment constitues a significant challenge for internationalntern conservation efforts. Since the increase in anthropogentic activities and inadequate plastic waste management over all years, Macao coastal ecosystems have been greatly impacted. Therefore, it is essential to assess the presence and characteristics of microplastics in both waters and sediments along the coastlines of Macao particularly focusing on mangrove and non-mangrove areas. This evaluation aims to gather data on the sources, transport mechanisms, and ecological impacts of microplastics in Macao's coastal waters. A recent local report has indicated that Macao's water sources are not completely free from contamination. This has become a significant concern, as coastal and wastewater sources are heavily polluted with microplastic particles. Macao has been referred to as one of the world's most pressing plastic ocean pollution areas, with one of the highest rates of such pollution globally. Microplastics, however, are not the only plastic pollutant found, as nanoplastics have been found in shore waters, harming ocean ecosystems and becoming incorporated into the food chain. This research was used to quantitatively estimate the density and occurrence of microplastics in Macao coastal ecosystems in mangrove and non-mangrove areas (Taipa Mangroves Wetland, Cotai Ecological Reserve, Coloane Village Wetland) and Hac Sa beach. The results show that the non-mangrove site has a density of microplastics at 267.98 pieces/kg, which has the lowest of all the sampling stations, and Taipa Mangroves Wetland, with the highest concentration of microplastics within the forest among the sampling stations in the mangrove zone of Macau. This research can also provide useful information for environmental conservation and management plans.

Road dust contains a variety of heavy metals and is a widely used indicator for monitoring pollution and assessing environmental and health risks in urban ecosystems. In this study, road dust was collected from 8 representative areas in Macao. The spatial distribution of heavy metal content in road dust in Macao was determined by extracting the heavy metal content in each sample. Heavy metals in road dust are mainly found on busy roads, and the production of these heavy metals mainly comes from the particles worn off in the work of transportation vehicles, such as tires, brake pads, road dust, and emissions from exhaust pipes, These heavy metal particles scattered on the road will remain on the road surface for a long period and cause environmental pollution. This sampling was also collected when there was no rainfall in Macao for more than 7 days, which also ensured that the heavy metal content in road dust distributed in time and space was as close to accurate data as possible. At the same time, in this collection of road dust regulations, the sampling is strictly followed by recording the area, traffic flow, weather, humidity, and other factors. The addition of a large statistical analysis of variables helped to correlate the elements studied with several local sources of pollution: from local industrial plants and related activities, pavement modifications, power plants, road traffic, and the resuspension of particulate matter (RPM). Our findings suggest that combining chemical and isotopic monitoring of road dust may help implement more effective environmental management measures to reduce its adverse effects on ecosystems and human health. This study analyzed the temporal and spatial distribution of heavy metals in road dust from different locations in Macao, revealing the current situation of heavy metal pollution and its potential threat to human health. The results show that heavy metals primarily originated from human activities such as transportation emissions, industrial activities, and road construction. Through detailed analysis of the sampling points in G 1-G8, it was found that the concentration of heavy metals varied significantly in different areas, especially in areas with heavy traffic flow, in which the heavy metal content was generally higher.

Macao, a densely urbanized region with limited freshwater resources, faces significant challenges in water security, relying on over 90% of raw water imports from the Mainland. This study investigates the quality of rainwater harvested from three representative rooftop types (blue metal, concrete, and green garden roofs) to establish a scientific basis for sustainable reuse. The research reveals distinct water quality patterns and first-flush effects across roof materials through field sampling and laboratory standard of parameters, including organic matter, turbidity, and nutrients. Key findings show that green roofs exhibit the highest pollutant concentrations (e.g., COD: 52.27 ± 26.00 mg/L and conductivity: 525.75 ± 203.60 μS/cm) due to vegetation decomposition and soil leaching. In contrast, blue steel tile roofs yield relatively cleaner runoff but with pronounced initial pollutant surges. Concrete roofs produce alkaline runoff (pH up to 8.63) due to cement mineral dissolution. Statistical analysis confirms conductivity and turbidity as robust predictors of dissolved pollutants, with significant correlations to other parameters, enabling rapid water quality assessment. The study further evaluates the first flush effect; recommendations include material-specific collection strategies, IoT-integrated smart monitoring systems, and policy incentives for green roof adoption to balance ecological benefits with water quality management. This research addresses critical gaps in Macao's rainwater management, providing a sustainable urban water resource optimization framework.

Mangrove resilience to anoxic conditions primarily occurs through adaptations in their root systems. Notably, increased root growth of existing pneumatophores in response to plastic suffocation has been observed in mangroves and can serve as a proxy to assess tree stress. The objective of this study is to determine the impact of varying levels of microplastic pollution on the morphological characteristics of mangrove plants. Fresh Kandelia obovata seedlings were collected from the Cotai Ecological Reserve, cultivated for 27 weeks, and subsequently exposed to polyethylene (PE) particles of 600 μm, 150 μm, and 13 μm in size at concentrations of 5% and 10% (w/w). The wet weight of the plant samples was measured at the beginning and end of the experiment, and morphological characteristics were recorded weekly. Morphological parameters including germination rate, number of leaves, root morphology, and survival rate, as well as environmental conditions (temperature and humidity), were evaluated to determine the influence of microplastic size, concentration, and environmental factors on plant development. Results indicate that smaller microplastics (13 μm) adversely affected the germination rate, leaf production, and survival of K. obovata. Furthermore, a higher concentration (10% w/w) of medium-sized microplastics (150 μm) led to a lower survival rate compared to the lower concentration group. These findings shows the negative impact of microplastic pollution on mangrove species and highlight the importance of addressing plastic contamination for effective mangrove conservation.

This study examined the microbial contamination characteristics of three different roof materials (green roof, metal roof, and concrete roof) during rainfall events. Through runoff samples collected from multiple rainfall events in the experimental rainwater collection system model, the pollution characteristics of total colony-forming units, Escherichia coli, and total coliforms were analyzed in combination with water quality parameters such as pH, turbidity, chemical oxygen demand (COD), and electrical conductivity. The study using the Wilcoxon Signed Ranks Test and found that the microbial contamination load of initial rainwater was significantly higher than that of subsequent runoff. The Mann-Whitney U test was used to compare the differences in microbial contamination caused by different roof materials. The results show that the metal roof performed the best in terms of microbial control, while the green roof had the poorest microbial control efficiency. The Spearman correlation analysis revealed that turbidity and conductivity were significantly positively correlated with microbial contamination, confirming that pollutants and nutrient ions are core factors driving microbial proliferation. Moreover, the metal roof exhibited outstanding disinfection efficacy under direct sunlight (microbial survival rate 0.00003% - 0.0004%), its high reflectivity and thermal conductivity working in synergy with UV radiation to destroy microbial DNA, while under shaded conditions, the sterilization efficiency decreased by approximately 100 times. The study suggests that metal roofs should be prioritized for use in water quality-sensitive scenarios. Green roofs need to be equipped with initial rainwater retention and substrate antibacterial improvement, and concrete roofs can enhance their antibacterial ability through hydrophobic surface treatment. The study provides a scientific basis for improving the design of rainwater collection systems in Macau, enriching the research cases of roof runoff pollution in tropical coastal cities, and is of great significance for improving the urban rainwater management system and protecting water environmental quality. 本研究考察了三种不同屋顶材料（绿色屋顶、金属屋顶和混凝土屋顶）在降雨期间的微生物污染特征。通过在实验雨水收集系统模型中多次降雨事件所采集的径流样本，结合 pH 值、浊度、化学需氧量（COD）和电导率等水质参数，对总菌落形成单位、大肠杆菌和总大肠菌群的污染特征进行了分析。研究采用威尔科克森符号秩检验，发现初期雨水的微生物污染负荷显著高于后续径流。采用曼 - 惠特尼 U 检验比较了不同屋顶材料造成的微生物污染差异。结果表明，金属屋顶在微生物控制方面表现最佳，而绿色屋顶的微生物控制效率最差。斯皮尔曼相关性分析表明，浊度和电导率与微生物污染显著正相关，这证实了污染物和营养离子是驱动微生物增殖的核心因素。此外，金属屋顶在阳光直射下表现出卓越的消毒效果（微生物存活率 0.00003% - 0.0004%），其高反射率和热导率与紫外线辐射协同作用，破坏微生物 DNA，而在遮阴条件下，其杀菌效率降低约 100 倍。该研究建议，在水质敏感的场景中应优先使用金属屋顶。绿色屋顶需要配备初期雨水截留装置和基质抗菌改进措施，而混凝土屋顶可通过疏水表面处理来增强其抗菌能力。该研究为澳门雨水收集系统的设计改进提供了科学依据，丰富了热带沿海城市屋顶径流污染的研究案例，对于完善城市雨水管理系统和保护水环境质量具有重要意义。

Indoor air quality (IAQ) is a critical public health concern given that individuals spend approximately 90% of their time in enclosed environments. Poor IAQ has been linked to respiratory diseases, cardiovascular conditions, and cognitive impairment, while improvements in air quality have demonstrated measurable benefits, including enhanced workplace productivity (2 to 7 times greater efficiency) and reduced prevalence of asthma and allergies. This study investigates IAQ across diverse occupational settings in Macao, employing a combination of environmental sampling and the U.S. Environmental Protection Agency (USEPA) exposure model to assess health risks associated with prolonged indoor exposure. Field sampling was conducted in five representative workplaces (restaurants, student dormitories, auto repair shops, offices, and parking security rooms), and particulate matter was collected from air conditioning filters to detect heavy metal content in the samples. Subsequently, we applied the PMF model to analyze the pollution sources and the US EPA exposure model to assess health risks and evaluate the carcinogenic risks in the five representative workplaces. The forward matrix factorization (PMF) model identified six major pollution sources: traffic emissions (23.8%, Zn/Sb), building materials (21.6%, Al/Ti), cooking activities (18.5%, Na/Ca), chemicals (15.2%, Ag/B), electronic devices (12.3%, Tl), and outdoor activities (8.6%, Co/Ni). The health risk assessment using the US Environmental Protection Agency (USEPA) exposure model showed that the overall non-carcinogenic risk (HI = 6.16×10^-6) and carcinogenic risk (6.57×10^-9) were below the safety threshold, indicating that its direct health hazard was minimal. However, nickel and chromium were identified as the main contributors to potential long-term risks.This study is currently only a preliminary exploratory study and provides a basis for subsequent research.These findings underscore the necessity for site-specific IAQ management strategies, such as enhanced mechanical ventilation, air filtration upgrades, and occupancy regulations. The study provides policymakers with evidence-based insights to mitigate health risks in high-exposure environments while establishing a framework for future IAQ monitoring in urban settings.

Nature-based Solutions (NbS) offer a sustainable approach to mitigating climate change and biodiversity loss while delivering socio-economic benefits. This study examines mangroves as a key NbS in Macao, assessing their ecosystem services and economic valuation through a hedonic pricing model. Despite their limited spatial coverage, Macao's mangroves provide critical services, including coastal protection, carbon sequestration, and habitat provision, yet face threats from invasive species and urbanization. The research employs a hedonic pricing model to analyze the relationship between property prices and proximity to mangrove ecosystems in Macao Peninsula, Taipa, and Coloane. Results demonstrate a statistically significant negative correlation, indicating that residential properties closer to mangrove areas command higher prices, reflecting the premium placed on ecological amenities. The model explains 65.0% of price variation, underscoring mangroves' influence on real estate values. This study contributes a novel valuation framework for mangrove ecosystem services in high-density coastal cities, integrating ecological and economic perspectives. The findings support evidence-based policy recommendations for mangrove conservation and sustainable urban development. Future research should expand the model to incorporate additional variables and longitudinal data to enhance predictive accuracy and applicability across diverse coastal regions. Biodiversity assessment and conservation planning in highly urbanized environments. 基于自然的解决方案（NbS）为缓解气候变化和生物多样性丧失提供了一种可持续的方法，同时还能带来社会经济利益。本研究以澳门的红树林为例，探讨其作为关键的基于自然的解决方案的作用，通过享乐定价模型评估其生态系统服务和经济价值。尽管澳门红树林的分布面积有限，但它们提供了重要的服务，包括海岸保护、碳封存和栖息地提供，然而却面临着外来物种入侵和城市化的威胁。 研究采用享乐定价模型，分析澳门半岛、氹仔和路环地区房产价格与红树林生态系统距离之间的关系。结果表明，两者之间存在显著的负相关关系，即靠近红树林区域的住宅价格更高，这反映了人们对生态设施的重视。该模型解释了 65.0%的价格差异，突显了红树林对房地产价值的影响。 本研究为高密度沿海城市的红树林生态系统服务提供了一种新的估值框架，将生态和经济视角相结合。这些发现为红树林保护和可持续城市发展提供了基于证据的政策建议。未来的研究应扩展该模型，纳入更多变量和纵向数据，以提高预测的准确性和在不同沿海地区的适用性。在高度城市化环境中进行生物多样性评估和保护规划。

With the steady growth of the global population and the acceleration of the urbanization process, the carbon footprint generated by the food production system and thus by food waste (40 % of food is wasted globally) has a significant impact on the environment and for sustainable development. Dongguan, as a new first-tier city in China, has attracted many internal migrants from China to work and settle down. A large proportion of the city's waste is composed of organic waste, and household food waste is an important part of it. This may be due to the fact that families purchase too much food, set aside excessive amounts, or fail to consume the food before it spoils, resulting in a waste of resources that comes along with significant environmental impacts, especially in the form of greenhouse gas emissions. This research adopted the method of questionnaire survey. The questionnaire aims to gain an in-depth understanding of the food waste perception and situation in Dongguan’s household sector and its families. By covering questions in three aspects: the demographic information of the respondents, their views and perceptions of local food waste, and their behavioral habits, the questionnaire investigates the current situation and local challenges of household food waste in families (such as the situation of leftover dishes, the proportion of food waste in household garbage, etc.), analyzes the causes of waste (factors in links such as purchasing, cooking, and storing), explores the wider public's awareness and attitudes towards food waste (degree of attention, views on reduction measures, environmental awareness, etc.), and clarifies the behavioral habits of dealing with leftover food (handling methods, willingness to purchase discounted food, etc.), and analyzes the relationship between demographic characteristics and food waste, so as to provide a basis for formulating targeted strategies. The survey results show that there exists a significant degree of food waste in Dongguan households. The public's awareness and behavioral habits regarding food waste vary greatly, and there is much room for improvement and enhancement. It is urgent to strengthen publicity and education work, which will help improve the public's understanding of the harm of food waste and enhance their environmental awareness. The research finds that although the Dongguan Municipal Government attaches great importance to the problem of food waste, the current policies mainly focus on the catering industry. In terms of the governance of food waste at the family level, relevant measures still need to be further strengthened. This study analyzes the factors affecting household food waste generation and comprehensively reviews and evaluates relevant policies aimed at mitigating food waste in Dongguan. On this basis, this study provides preliminary suggestions for policymakers and government departments on regional and national level, aiming to point out the direction for future related research and work planning.

"Over time, the large shopping malls in Macao will require some changes to improve space utilization, resulting in renovation projects that affect indoor particulate matter (PM10 and PM2.5) concentrations. Employees work long hours in an environment where the ambient air quality is poor, directly affecting their work efficiency. Nonetheless, the concentration of PM produced by the interior renovation of shopping malls has yet to receive particular attention. Therefore, this study will investigate IAQ, in particular, PM10 and PM2.5 in large-scale shopping mall renovation projects in three different indoor locations (i.e., public, renovation, and construction areas) to understand the causes of indoor PM10 and PM2.5. This study will collect on-site PM data for analysis, examine whether the current control measures are appropriate and propose some improvements. The data collected will be compared with IAQ standards from the World Health Organization (WHO) and the Macao Meteorological and Geophysical Bureau (SMG), specifically PM concentrations. The research results can provide a reference guide for decision-makers, management, construction teams, design consultant teams and renovation teams of large-scale projects. In addition, the monitoring of IAQ can ensure a comfortable environment for employees and customers."

With the rapid urban development, Macao SAR has become one of regions with the with highest population density in the world, characterized by high traffic flow and dense building aggregations. Noise has become one of the major environmental problems in Macao. Besides having an impact on human health and wellbeing, noise pollution is known to impact ecological systems and the image of a place. Before proposing a plan to reduce noise pollution, it is necessary to have a general understanding of the current noise levels in Macao, how they have changed over time and the main noise pollution sources and environmental concerns. This dissertation relies on the publicly available data from DSPA (Macao Environmental Protection Bureau) monitoring stations concerning noise levels over the past decade. The main research goals were: 1) Characterize changes in noise levels from 2010 to 2021 during daytime, nighttime, and full-day from multiple noise stations located in Macao, Taipa, and Coloane Peninsula; and 2) associate changes in noise levels with potential factors such as location, number of residents/tourists, number of vehicles, among others. This work provides an important framework for future studies concerning noise monitoring and mitigation strategies

Food waste has become an increasingly pressing issue worldwide, and Macau is no exception. A substantial portion of municipal solid waste in Macau is comprised of organic waste, with household food waste being a significant contributor. This can be attributed to households purchasing excessive food, preparing more than necessary, or not consuming items before they spoil, leading to detrimental resource and environmental impacts, particularly in the form of greenhouse gas emissions. It is crucial for Macau to develop a sustainable food waste management system that fosters prevention and responsible consumption and to develop food waste recycling habits among its residents. This study employed a two-pronged approach: a literature review of food waste source separation policies and practices in four neighboring regions to identify adaptable good practice examples for Macau, and a questionnaire survey completed by 143 local residents. The survey aimed to comprehend residents' behaviors and awareness regarding food waste prevention and treatment, evaluate their satisfaction with Macau's existing food waste recycling program, examine their resistance and motivation toward participating in the recycling program, and assess their attitudes toward implementing a polluter-pays-principle system in Macau. The survey aimed to provide insights into the current state of household food waste in Macau and inform future waste management policies and strategies of stakeholders. The survey findings highlight the need for enhanced public awareness and education on food waste prevention. Additionally, upgrading recycling facilities may encourage residents to participate more actively in food waste recycling. Ultimately, implementing suitable policies can help prevent food loss and waste and regulate food waste generation and elevate recycling rates. This study offers preliminary recommendations for policymakers or government entities as a orientation for future planning

The inundation problem in Macao is getting more attention recently, especially after the destructive impacts of typhoons Hato (2017) and Mangkut (2019). The inundation caused by storm surges is getting more severe with the rapid sea-level rise in Macao. Moreover, the potential threat of a tsunami in Macao, may be enhanced with rising sea-level. This research evaluated the risk of coastal hazards in Macao by analyzing the local meteorological data. The results of the analysis indicate a rising trend in the tropical cyclone intensity and more severe storm surges are expected to occur in the future. Moreover, this research explores the potential of Nature-based Solutions (NbS), particularly mangroves, to address the inundation problem in Macao. The study included a preliminary laboratory-based experiment and the application of local mangroves data in numerical models. The results of the experiment and numerical models demonstrate the ability of mangroves to attenuate waves. These findings, although preliminary, indicate that mangroves could be a promising NbS to address inundation issues in Macao. To effectively implement this NbS, further field investigations are needed to measure attenuation in-situ, as well as determine optimal locations for mangrove restoration projects

Climate change is a global issue but its impact can be felt locally. Macau SAR has been rapidly developing since the single shift towards a gaming industry-dominated economy, the overwhelming anthropogenic activities contributing to increasing pollution. Mangroves, which play an essential role as the blue carbon system with a high carbon sequestration rate could be a natural base solution to the pollution. This study aims to determine 1) the total organic Carbon (TOC) in the soil of Macau mangrove sites, 2) comparison with the methodology evaluating the organic Carbon, and 3) organic Carbon comparison between Macau and other regions. Soil sampling were processed under the Blue Carbon Initiative guideline, and the samples were divided into two parts for determining the TOC%, combustion method from Hong Kong, and methodology of ashing in our laboratory. The overall estimated TOC% of Macau mangrove sites was 1.29%. There are still a lot of potentials in Carbon storage and for climate change mitigation in Macau

Road transportation is one of the main sources of air pollution in Macao. This study mainly explores four major roadside locations with high traffic flow in Macao from March to May 2022 and measures their pollutant concentrations (PM10 and PM2.5), traffic flow and their fuel type, as well as considering the meteorological parameters and pollutant concentration of SMG Macao to analyze the relationship between traffic flow and pollutants on roadside locations. Under the measuring distance between 3 and 6 meters, showing that the four locations had a good correlation with the roadside station data provided by SMG on both weekdays and weekends/holidays (PM2.5: R2 is 0.59 to 0.81 on weekdays and 0.79 to 0.88 on weekends/holidays, p<0.01; PM10: R2 is 0.33 to 0.82 on weekdays and 0.30 to 0.58 on weekends/holidays, p<0.05), the overall PM2.5 is 41 to 86% higher than that of the same period of Macao roadside station (SMG), and 68 to 186% higher than that of Taipa Ambient (SMG), indicating that it is more harmful to daily pedestrians. The overall relationship between PM concentration and traffic flow is small on the long-term scale (PM2.5: R2 is 0.01 to 0.13; PM10: R2 is 0.00 to 0.02). This study also analyzed air quality on EBL, the overall PM2.5 and PM10 decreased by 12.3% to 24.8% compared with non-EBL during the period, so that is indeed beneficial to the reduction of pollutant concentrations. In addition, narrower roads were overall higher when road widths added for comparison. Lastly, meteorological data added for comparison, except for relative humidity, it can be found that there is a significant correlation with long-term pollutants (p<0.05). While previous studies have found that single-day traffic flow is related to the increase in PM concentration, this paper is more inclined to their two-way effect when exploring their long-term relationship

" Air pollution in Macau has become a serious problem following the Pearl River Delta’s (PRD) rapid industrialization that began in the 1990s. While there has been continual improvement in recent years, harmful air pollutant concentration levels are still common, impacting Macau residents' health and creating long-term medical costs to local society. With this in mind, Macau needs an air quality forecast system that accurately predicts pollutant concentration and an early alert system instead of only daily real-time reminders. Some scholars have previously carried out studies to develop an air quality forecast for Macau by successfully using statistical models. Therefore, pursuant to the outcomes of previous studies, this dissertation aims to build upon research results and explore further possibilities of building a better ML air quality forecast model based on the time series of air pollutants concentration and meteorological data. Four different state-of-the-art ML algorithms were used to create predictive models to forecast PM2.5, PM10, and carbon monoxide (CO) concentrations for the next 24 and 48-hour. These were Support Vector Machine (SVM), Artificial Neural Networks (ANN), Random Forest (RF), and Extreme Gradient Boosting (XGBoost). In addition, Multiple Linear Regression MLR, a standard ML model, was used for this dissertation as a baseline reference for performance comparison. The daily measurements of air quality data in Macau from 2016 to 2021 were collected for this dissertation. The 2020 and 2021 datasets were used for model testing while the four-year data prior to 2020 and 2021 were used to build and train the ML models. The results showed that SVM, ANN, RF, and XGBoost were able to provide a very good performance in building up a 24-hour forecast with higher R2 and lower RMSE, MAE, and BIAS. Meanwhile, all ML models in 48-hour forecasting performance were satisfactory enough to be accepted as a two-day continuous forecast even if the R2 value was lower than the 24-hour forecast. The 48-hour forecasting model could be further improved by proper feature selection based on the 24-hour dataset, using the SHAP value test, and the adjusted R2 value of the 48-hour forecasting model."

Informal recycling plays a crucial role in municiapl solid waste management in many cities, particularly in the global South. This study examines the practices, challenges, and opportunities of informal recycling in Macau, a small city and Self Autonomous Region (S.A.R.) in China. Using qualitative research methods, including semi-structured interviews, this study explores the motivations and strategies of informal recyclers, the challenges they face, and the potential for collaboration with formal waste management systems. The findings of this study reveal that informal recycling in Macau is a complex and multifaceted reality and practice that involves a range of actors, from waste pickers to small-scale processors to exporters, all with their specific challenges. Informal recyclers are motivated by economic necessity, and they employ a variety of strategies to collect and process recyclable materials. However, they also face significant challenges, including high rental and transportation costs, lack of manpower, China’s waste import policies and ensuing restrictions, fluctuating global price rates of materials and the unstable income as serious consequence, accompanied by limited support from the local Government. This study also identifies opportunities for sustainable development of informal recycling in Macau, supported by the analysis of data collected via questionnaire survey regarding Macau citizens’ waste separation habits and their willingness to pay for resource separation and recovering process. The identified oppurtunities include establishing partnerships between informal and formal waste management actors, improving the infrastructure, and introducing environmental levy system and consistent policies and regulations. Overall, this study contributes to a better understanding of the role of informal recycling sector in waste management in Macau and provides insights into potential strategies for improving the sustainability of resource and waste management practices in the city

With water being an essential for life on Earth, it is vital to preserve it and regenerate it, in order to be available for a myriad of uses. Though many types of wastewater management and treatment are available, most rely on high energy input and are therefore not ideal for many circumstances. Constructed wetlands (CW) are an alternative nature-based solution to be applied to wastewater treatment. This study undertakes a Life-Cycle Assessment (LCA) of a CW as a means of wastewater treatment and aims to understand how these systems can be an environmentally conscious alternative. The CW under study is located in a rural mountain area in the north of Portugal. Receives wastewater from a tourism unit and operates with horizontal subsurface. The LCA analyses the CW through the construction, operation (treatment), and composting phases. This approach allows the entire scope of the life cycle to be included, of which, the composting phase has been absent in similar LCA previously undertaken. Analysis focuses on the impact categories: Ozone Layer Depletion Potential, Global Warming Potential, Acidification Potential, Eutrophication Potential and Human Toxicity Potential. Of the five categories, none increase during the treatment phase, and indeed, Acidification Potential, Eutrophication Potential, and Human Toxicity potential all decrease. Ozone Layer Depletion Potential and Global Warming Potential increase significantly during the construction and composting phases respectively. Both can be rationalized, with the former being a result of heavy diesel machinery use in construction and the latter a natural byproduct of composting. The results are net positive and display the ability for CW as a low energy wastewater treatment which can limit environmental impact by choice of construction and composting methodology