Search Results (11)

The construction sector, particularly the production of materials like cement and steel, is a major contributor to global CO₂ emissions, with cement alone responsible for about 8%. Conventional masonry relies heavily on cement, increasing embodied carbon and costs, but standardized data on low-carbon alternatives such as compressed stabilized earth blocks (CSEBs) remain scarce, limiting their adoption in sustainable housing. To support the United Nations Environment Program (UNEP) and the Paris Agreement goals for net-zero embodied carbon in building materials by 2050, this study aims to assess the production and performance of CSEBs as a low carbon alternative to conventional masonry. It specifically addresses the research gap on technical performance and carbon savings, providing new empirical evidence for Ethiopian soils. Soil samples from Kara (east of Addis Ababa) were analyzed for grading, plasticity, and chemical composition. Blocks were produced with Portland pozzolana cement (4–12%) under compaction pressures of 4–10 MPa and tested for compressive strength and water absorption over 56 days. Results show that 6% cement content achieved >2 MPa compressive strength, meeting the structural requirements, while higher cement content and pressure improved strength and reduced absorption. Compared to hollow concrete blocks, CSEBs cut cement use by over 50%, avoiding up to 2 tons of CO₂ per 100 m² of wall. These findings confirm CSEBs as a technically viable and climate-conscious solution for affordable housing and support their integration into sustainable construction practices. Full article

According to statistics from the United Nations Environment Program (UNEP), the construction industry accounts for approximately 30% to 40% of global energy consumption and greenhouse gas emissions, making it a major source of carbon emissions. As a critical component of urban construction, residential buildings are characterized by their large scale and significant potential for carbon reduction. Building on this context, this study utilizes diversified geospatial data and applies the life-cycle stage framework for residential buildings alongside the emission factor method to calculate total carbon emissions during the material production, construction, and operation phases. It systematically analyzes the distribution characteristics and spatial evolution trends of life-cycle carbon emissions for urban residential buildings. The findings reveal that 63.06% of the cumulative carbon emissions from residential buildings in Xi’an originate from the operation phase, underscoring the importance of optimizing carbon emissions in this phase as a critical priority for future reductions. Additionally, the spatial distribution of residential building carbon emissions exhibits significant clustering, with an increasingly pronounced expansion pattern. Over time, the direction of expansion has shifted from a northeast–southwest orientation to a northwest–southeast trajectory and continues to extend toward peripheral areas. Economic growth, increased urbanization, and the intensive consumption of specific building materials are identified as significant drivers of residential carbon emissions, while population growth and improvements in material utilization efficiency help mitigate emissions to some extent. This study offers valuable insights to support the green development of China’s construction industry and to advance energy-saving and carbon-reduction strategies. Full article

Plastic waste (PW) presents a significant environmental challenge due to its persistent accumulation and harmful effects on ecosystems. According to the United Nations Environment Program (UNEP), global plastic production in 2024 is estimated to reach approximately 500 million tons. Without effective intervention, most of this plastic is expected to become waste, potentially resulting in billions of tons of accumulated PW by 2060. This study explores innovative approaches to convert PW into high-value carbon nanomaterials (CNMs) such as graphene, carbon nanotubes (CNTs), and other advanced carbon structures. Various methods including pyrolysis, arc discharge, catalytic degradation, and laser ablation have been investigated in transforming PW into CNMs. However, four primary methodologies are discussed herein: thermal decomposition, chemical vapor deposition (CVD), flash joule heating (FJH), and stepwise conversion. The scalability of the pathways discussed for industrial applications varies significantly. Thermal decomposition, particularly pyrolysis, is highly scalable due to its straightforward setup and cost-effective operation, making it suitable for large-scale waste processing plants. It also produces fuel byproducts that can be used as an alternative energy source, promoting the concept of energy recovery and circular economy. CVD, while producing high-quality carbon materials, is less scalable due to the high cost and required complex equipment, catalyst, high temperature, and pressure, which limits its use to specialized applications. FJH offers rapid synthesis of high-quality graphene using an economically viable technique that can also generate valuable products such as green hydrogen, carbon oligomers, and light hydrocarbons. However, it still requires optimization for industrial throughput. Stepwise conversion, involving multiple stages, can be challenging to scale due to higher operational complexity and cost, but it offers precise control over material properties for niche applications. This research demonstrates the growing potential of upcycling PW into valuable materials that align with global sustainability goals including industry, innovation, and infrastructure (Goal 9), sustainable cities and communities (Goal 11), and responsible consumption and production (Goal 12). The findings underscore the need for enhanced recycling infrastructure and policy frameworks to support the shift toward a circular economy and mitigate the global plastic crisis. Full article

The “Green Nudges” program, developed within the framework of the United Nations Environment Programme (UNEP), is based on behavioral science and nudge theory. Aimed primarily at universities, it explores ways to adopt a more environmentally friendly lifestyle. Studies show that many young people recognize climate change as a major problem but that it leaves them feeling helpless and anxious—something that our teaching practice confirms. As we had had no success teaching sustainability using conventional approaches, we used the pedagogical design capacity (PDC) principle to develop a novel workshop format and implement it in a pilot series of three repeated workshops. The workshop concept is based on empowering educators and students to tackle emerging global issues while also boosting critical thinking, field research, and teamwork skills. An important part of the integration of different tools was based on supporting students’ self-direction and knowledge- and evidence-based decision making. The results demonstrate that the proposed pedagogical framework resonates with and empowers students. At the same time, the workshop empowers educators to competently navigate complex and sustainability-oriented topics within the field of education for sustainable development (ESD). Full article

Arid and semiarid regions are geographic units that cover approximately 43% of the earth’s surface worldwide, and conditions of extreme drought and reduced vegetation cover predominate in these regions. In Mexico, arid and semiarid ecosystems cover more than half of the territory, with desertification, mainly caused by anthropogenic activities and climatic events, as the main problem in these regions. The present research aimed to assess, identify, and classify arid and semiarid zones by employing a methodology based on multicriteria evaluation analysis (MCA) using the weighted linear combination (WLC) technique and geographic information systems (GIS) in the hydrological administrative regions (HARs) of the North Pacific, Northwest, and Baja California Peninsula, located in Northwest Mexico. Data related to aridity, desertification, degradation, and drought were investigated, and the main factors involved in the aridity process, such as surface temperature, soil humidity, precipitation, slopes, orientations, the normalized difference vegetation index (NDVI), and evapotranspiration, were obtained. For the standardization of factors, a fuzzy inference system was used. The weight of each factor was then determined with the analytical hierarchy process (AHP). To delimit arid regions, the classification of arid zones proposed by the United Nations Environment Program (UNEP) was used, and the result was an aridity suitability map. To validate the results, the sensitivity analysis method was applied. Quantitative and geospatial aridity indicators were obtained at the administrative hydrological level and by state. The main results indicated that semiarid and dry subhumid zones predominated, representing 40% and 43% of the surface of the study area, respectively, while arid regions represented 17%, and humid regions represented less than 1%. In addition, of the states for which 100% of the surface lay in the study area, it was observed that Baja California and Baja California Sur had the largest arid and semiarid zones, while subhumid regions predominated in Sonora and Sinaloa. Full article

Mainstreaming biodiversity in production landscapes ensures conservation and sustainable use of agricultural biodiversity, the key objectives of the Convention on Biological Diversity (CBD) and the projects supported by the United Nations Environment Program (UNEP) Global Environment Facility (GEF). Mainstreaming integrates biodiversity in existing or new programs and policies, both cross-sectoral and sector-specific. The conventional model of agricultural production with limited diversity in production systems and use of high chemical input has taught us a valuable lesson as it is adversely impacting the environment, the essential ecosystem services, the soil health and the long term sustainability of our food systems. Using a qualitative participant observation approach, our study investigated four distinct traditional Indian production landscapes to gage (i) the farming communities’ response to institutional policies, programs and agricultural biodiversity-related activities in traditional Indian production landscapes and (ii) opportunities and challenges for sustainable development in smallholder traditional Indian farming systems. Results indicate that the top-down decision-making regime is the least effective towards achieving sustainable development in traditional Indian farming landscapes and that farmers’ experiential knowledge on participatory biodiversity management, maintenance and use for sustainable development are of critical importance to India’s agriculture and economy. Reclaiming agriculture’s spiritual roots through organic farming and locally grown food emerged as key, including the need for designing and implementing a more sovereign food system. Revisiting traditional smallholder farming under the COVID-19 pandemic and lessons learned for repurposing India’s agricultural policy are also highlighted. Full article

According to the United Nations Environment Program (UNEP) annual Emissions Gap Report 2019, further reductions in greenhouse gas (GHG) emissions are needed to reduce climate change impacts. In Japan, the 2030 Intended Nationally Determined Contribution (INDC) target is an emissions reduction of 26% compared to 2013. The World Health Organization (WHO) declared that the coronavirus (COVID-19) outbreak has led to 43,341,451 confirmed cases and 1,157,509 confirmed deaths globally and affected 218 countries (as of 27 October 2020). In Japan, as of the same date, 96,948 infectious cases and 1724 deaths related to the new coronavirus had been recorded. These numbers continue to increase. In Japan, in March 2020, the number of international tourist arrivals decreased by about 93% compared to last year at the same period. The World Tourism Organization (UNWTO) reported several significant scenarios for the tourism industry. COVID-19 is the greatest shock to international tourism since 1950 and represents an abrupt end to the 10-year period of sustained growth that followed the 2009 financial crisis. It was thought that it would be possible to analyze the economic, environmental, and social impacts of rapid social changes. Thus, this study estimates changes in Japan’s tourist consumption, the carbon footprint (CFP), and employment due to the influence of the COVID-19 pandemic. The calculations in this study adopt a lifecycle approach using input–output tables. Based on these observations, this study uses four scenarios (SR 1, no recovery until December; SR 2, recovery from October; SR 3, recovery from July or September; and SR 0, same growth rate as 2018–2019) for Japan to calculate the CFP and employment change using input–output table analysis based on tourist consumption, which is a tourism metric. According to our results (2019 vs. SR 1 and 3), the consumption loss is between 20,540 billion yen (−65.1%) and 12,704 billion yen (−39.1%), the CFP reduction is between 89,488 kt-CO₂eq (−64.2%) and 54,030 kt-CO₂eq (−37.5%), and the employment loss is between 2,677,000 people (−64.2%) and 1,678,000 people (−37.5%). As of November 2020, the tourism industry continues to be affected by the COVID-19 pandemic. In the post-COVID-19 society, it will be necessary to maintain the GHG emissions reductions achieved in this short period and realize economic recovery. This recovery must also be sustainable for tourism stakeholders and society. Full article

Sustainable development is a major concern for developing and developed economies as economic growth has to led to scarcer and more expensive resources. Although countries have established public policies focusing on resource and energy efficiency, there is an increasing need for a coordinated industrial strategy able to create sustainable wealth through a holistic management of natural resources, capable of “decoupling” economic growth from resource extraction and natural deterioration. Consequently, the objective of the present research is to develop a decoupling model able to create increasing economic returns, reducing the social gap and regenerating the natural capital for regions in developing countries. Departing from a literature review on peer reviewed articles on successful industrial cases of decoupling around the world, we contrasted the linear production model with the United Nations Environment Program (UNEP)’s current four decoupling indicators in order to propose a more robust model. The result was an eight-factor decoupling model that used a well-supported framework for sustainable wealth creation named “circular value ecosystem” (CVES). By using system dynamics, we deployed the proposed framework using system dynamics modeling in order to improve the understanding of our proposal. We found that this model, with the proper regional conditions in developing countries, can: (1) reduce, through substitution, the consumption of natural resources; (2) produce alternative economic increasing returns; (3) reduce the negative environmental impacts; and (4) create self-sustainable wealth for the economy, the environment, and the social development of most stakeholders of these regions. Decoupling economic growth represents a complex and challenging task whose successful implementation can only be achieved if managed at a regional level with a systemic approach. Full article

On 4 August 2011, United Nations Environment Program (UNEP) submitted an unprecedented, scientific, groundbreaking environmental assessment report (EAR) on Ogoniland to the Nigerian government. This was the outcome of a 14-month intensive evaluation of the extent of pollution. The intention was that UNEP’s recommendations would be implemented to restore the devastated environment, on the one hand, and on the other, counteract the numerous environmental health issues that have for decades, plagued Ogoniland. However, five years post-EAR, and despite the seriousness of the situation, no significant resolution has occurred on the part of the government or the Shell Petroleum Development Company (SPDC) or Shell. To date, millions of Niger Delta residents particularly those living in the oil-bearing communities, continue to suffer severe consequences. Although the assessment was conducted in Ogoniland, other communities in the Niger Delta are also affected. This article explores prevailing issues in the Niger Delta, using Ogoniland (a microcosm of the Niger Delta) as an example. A multidisciplinary approach for sustainable mitigation of environmental health risks in the Niger Delta is paramount, and environmental management tools offer valuable strategies. Adopting the UNEP’s recommendations for addressing environmental health problems requires implementing the environmental management/environmental management system (EM/EMS) model. However, the persistent lack of political will on the part of the Nigerian government, and the grossly nonchalant attitude by Shell remain major obstacles towards executing UNEP’s recommendations. Full article

Water resources in Mediterranean coastal aquifers are subject to overexploitation leading to an increase in seawater intrusion. Based on the United Nations Environment Program, “UNEP” 75% of people in the world will live in coastal cities by 2020. This is having a major impact on the salinization process. This paper deals with the impact of demographic evolution on seawater intrusion and considers the case of the lower Tripoli aquifer in Lebanon. A numerical model based on the sharp interface approach is implemented using “Freefem++” to access the seawater intrusion. The model is verified against an analytic and a numerical solution. It is calibrated and validated against hydraulic head observations (RMSD = 0.819 m). Then several scenarios of pumping are applied based on available demographic growth rates to quantify the impact on seawater intrusion. The projection scenarios show that if the current pumping rates are maintained while maintaining the demographic evolution, the pumping wells will be salinized within 2 decades in the highly populated areas. Full article