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Version [2.0] — [pyMCMA: Uniformly distributed Pareto-front representation]
Get PDFpyMCMA is the Python implementation of a novel method for autonomous computation of the Pareto-front representation composed of efficient solutions distributed uniformly in terms of the distances between neighbor Pareto solutions. pyMCMA supports scientific, i.e., objective, model analysis by providing preference-free Pareto front representation.
The update provides new functionalities and enhancements. The former include clustering of the Pareto-front solutions. The enhancements include internal software improvements, optional customization of some parameters, as well as a new functionalities that might be used by advanced users
Electrification-enabled production of Fischer-Tropsch liquids – A process and economic perspective
Get PDFTransitioning to biofuels is crucial for reducing greenhouse gas (GHG) emissions in transportation, but limited biomass availability requires maximizing carbon efficiency. This study evaluates Fischer-Tropsch liquid (FTL) production from biomass, focusing on the impact of partial electrification and carbon capture and storage (CCS) on efficiency and flexibility. Five configurations—ranging from a biomass-intensive base case to a fully electrified process—are simulated and assessed through techno-economic and GHG evaluations under fluctuating energy prices. Full electrification achieves the highest carbon efficiency, increasing carbon-to-liquid fuel conversion from 37 % to 91 %, but faces challenges due to high electricity demand (up to 2.5 MWh per MWh of fuel) and reliance on low-carbon grids. Partial electrification offers a cost-effective alternative, reducing production costs by up to 40 % compared to fully electrified cases, while maintaining a carbon efficiency of around 60 %. CCS enables net-negative emissions, though its viability hinges on sufficiently strong carbon pricing incentives. Compliance with sustainability mandates, such as Renewable Fuels of Non-Biological Origin (RFNBO) requirements, depends on access to decarbonized electricity. Overall, partially electrified BtL pathways enhance carbon utilization, reduce emissions, and offer resilience to market fluctuations. These pathways provide a promising balance of environmental and economic performance, outperforming both traditional BtL under high biomass prices and fully electrified e-fuels in terms of cost. Their advantages make them attractive from both investment and policy perspectives—especially in markets supported by stable electricity prices, carbon incentives, and sustainability-driven regulation
Economically optimal management of salmon louse requires adapting to their drug-resistance rather than attempting their eradication
Get PDFThe growing global demand for seafood and concerns about overfishing have spurred the rapid expansion of aquaculture. In aquaculture, managing diseases and parasites presents a critical problem, with drug-based solutions being increasingly challenged by the evolution of drug resistance. In this study, we focus on managing salmon louse in the context of open-cage salmon mariculture with potential for the evolution of drug resistance. We devise a model combining parasite dynamics and fish dynamics in a system of fish farms connected to each other by dispersive stages of the parasite and then evaluate the system-wide economic performance of different management strategies involving three parasite-control measures: drug treatment (administering medicine through fish feed), mechanical treatment (pumping fish through a system of water jets and/or soft brushes), and depopulation (emptying a whole farm prematurely). Drug treatment controls drug-sensitive lice at low cost but becomes ineffective in the presence of drug-resistant lice. Mechanical treatment can clear both types of lice but at the cost of diminished fish growth and additional fish mortality. Depopulation removes both the fish and the parasites within the farm but results in prematurely harvested fish that fetch a lower price. Our results suggest that even when the drug is used only once per production cycle and mechanical treatment and depopulation provide the main control of the parasite, the spread of drug resistance is unavoidable in an open-cage system. Furthermore, it is often not economically optimal to drive resistance to the lowest possible level by minimizing drug use: because resistant lice are assumed to have a slightly reduced fecundity, slightly fewer non-drug treatments are needed for controlling drug-resistant parasites than drug-sensitive parasites. Building on these insights, our model predicts that economically optimal parasite management in the presence of drug resistance combines all three parasite-control measures: mechanical treatment is the main measure to reduce louse infestations, depopulation allows shorter production cycles that become optimal under reduced salmon growth and survival that result from frequent mechanical treatments, and the drug is used not only to provide some parasite control but also to keep the resistant parasites prevalent. Our results thus underscore the need for effective parasite management strategies in salmon aquaculture accounting for the unavoidable prevalence of drug resistance. Notably, the economically optimal approach does not involve combating resistance but rather adapting to it and capitalizing on its positive effects
Estimation of Impact of Disturbances on Soil Respiration in Forest Ecosystems of Russia
Get PDFSoil respiration (Rs) is a significant contributor to the global carbon cycle, with its two main sources—microbial (heterotrophic, Rh) and plant root (autotrophic, Ra) respiration—being sensitive to various environmental factors. This study investigates the impact of ecosystem disturbances (Ds), including fire, biogenic (insects and pathogens), and harvesting, on soil respiration in Russia’s forest ecosystems. We introduced response factors to account for the effects of these disturbances on Rh over three distinct stages of ecosystem recovery. Our analysis, based on data from case studies, remote sensing data, and the national forest inventory, revealed that Ds increase Rh by an average of 2.1 ± 3.2% during the restoration period. Biogenic disturbances showed the highest impacts, with average increases of 16.5 ± 3.2%, while the contributions of clearcuts and wildfires were, on average, less pronounced—2.0 ± 3.1% and 0.8 ± 3.3%, respectively. These disturbances modify forest soil dynamics by affecting soil temperature, moisture, and nutrient availability, influencing carbon fluxes over varying timescales. This research underscores the role of ecosystem disturbances in altering soil carbon dynamics and highlights the need for improved data and monitoring of forest disturbances to reduce uncertainty in soil carbon flux estimates
Social Intelligence Mining: Transforming Land Management with Data and Deep Learning
Get PDFThe integration of social intelligence mining with Large Language Models (LLMs) and unstructured social data can enhance land management by incorporating human behavior, social trends, and collective decision-making. This study investigates the role of social intelligence—derived from social media—in enhancing land use, urban planning, and environmental policy crafting. To map the structure of public concerns, a new algorithm is proposed based on contextual analysis and LLMs. The proposed method, along with public discussion analysis, is applied to posts on the X-platform (formerly Twitter) to extract public perception on issues related to land use, urban planning, and environmental policies. Results show that the proposed method can effectively extract public concerns and different perspectives of public discussion. This case study illustrates how social intelligence mining can be employed to support policymakers when used with caution. The cautionary conditions in the use of these methods are discussed in more detail
Reed pyrolysis system using multi-stage quench scheme for furfural and chemical production: Process analysis and life cycle assessment
No full textThis study presents an efficient utilization strategy for reed pyrolysis products, focusing on furfural as the primary product, along with acetic acid, wood vinegar, and phenol-rich oil. Based on this, the Energy-Integration Resource Utilization (EIRU) process, which incorporates a multi-stage quenching method, is developed. This process effectively removes most water from the main organic compounds during condensation by harnessing the internal heat of the high-temperature pyrolysis product stream from the reactor. Compared to conventional pyrolysis process, the EIRU can reduce energy consumption by 50 %. Life cycle assessment reveals that the EIRU process significantly reduces key environmental impact factors, including 90.15 kg CO2 eq. reduction in Global Warming Potential (GWP), 22.95 kg 1,4-DB eq. reduction in Human Toxicity Potential (HTP), and 1.86 kg Sb eq. reduction in Abiotic Depletion Potential (ADP). Additionally, the EIRU process yields a profit of 151.69 USD/ton, which is 14.81 USD/ton higher than the conventional process. This study highlights the superior environmental and economic performance of the EIRU process, positioning it as a more sustainable and profitable solution for reed pyrolysis
The pursuit of 1.5°C endures as a legal and ethical imperative in a changing world
No full textAs the world nears 1.5°C of global warming, near-term emissions reductions and adequate adaptation become ever more important to ensure a safe and livable planet for present and future generation
Managing space debris: Risks, mitigation measures, and sustainability challenges
Get PDFSpace debris consists of non-functional, human-made objects remaining in Earth's orbit or entering the atmosphere, creating significant challenges for space operations. Current surveillance systems track nearly 40,000 larger debris fragments, yet it is estimated that hundreds of thousands of smaller pieces and millions of tiny, untracked particles further contribute to the risk of high-velocity collisions. These objects threaten spacecraft integrity, satellite functionality, and the long-term sustainability of space activities. This review article investigates the hazards posed by space debris, providing an overview of its impact on satellite operations, crewed space missions, and orbital stability. It examines risk mitigation strategies, including the enforcement of stricter disposal regulations, advancements in satellite design for controlled re-entry or deorbiting, and the active removal of large debris objects. A structured approach to space debris mitigation is also explored, outlining a proposed four-step strategy: designing spacecraft for impact resistance, implementing advanced remote tracking and monitoring systems, integrating onboard detection and avoidance mechanisms, and developing impact mitigation strategies to minimize damage. Additionally, the importance of enhanced tracking technologies and international cooperation is underscored, as collective efforts are necessary to address this escalating issue. Increasing awareness of the growing risks and exploring practical mitigation strategies strengthens ongoing efforts to safeguard space activities and ensure the long-term viability of Earth's orbital environment