• Energy Research

AbstractPeatlands cover only 3–4% of the Earth’s surface, but they store nearly 30% of global soil carbon stock. This significant carbon store is under threat as peatlands continue to be degraded at alarming rates around the world. It has prompted countries worldwide to establish regulations to conserve and reduce emissions from this carbon rich ecosystem. For example, the EU has implemented new rules that mandate sustainable management of peatlands, critical to reaching the goal of carbon neutrality by 2050. However, a lack of information on the extent and condition of peatlands has hindered the development of national policies and restoration efforts. This paper reviews the current state of knowledge on mapping and monitoring peatlands from field sites to the globe and identifies areas where further research is needed. It presents an overview of the different methodologies used to map peatlands in nine countries, which vary in definition of peat soil and peatland, mapping coverage, and mapping detail. Whereas mapping peatlands across the world with only one approach is hardly possible, the paper highlights the need for more consistent approaches within regions having comparable peatland types and climates to inform their protection and urgent restoration. The review further summarises various approaches used for monitoring peatland conditions and functions. These include monitoring at the plot scale for degree of humification and stoichiometric ratio, and proximal sensing such as gamma radiometrics and electromagnetic induction at the field to landscape scale for mapping peat thickness and identifying hotspots for greenhouse gas (GHG) emissions. Remote sensing techniques with passive and active sensors at regional to national scale can help in monitoring subsidence rate, water table, peat moisture, landslides, and GHG emissions. Although the use of water table depth as a proxy for interannual GHG emissions from peatlands has been well established, there is no single remote sensing method or data product yet that has been verified beyond local or regional scales. Broader land-use change and fire monitoring at a global scale may further assist national GHG inventory reporting. Monitoring of peatland conditions to evaluate the success of individual restoration schemes still requires field work to assess local proxies combined with remote sensing and modeling. Long-term monitoring is necessary to draw valid conclusions on revegetation outcomes and associated GHG emissions in rewetted peatlands, as their dynamics are not fully understood at the site level. Monitoring vegetation development and hydrology of restored peatlands is needed as a proxy to assess the return of water and changes in nutrient cycling and biodiversity.

The construction industry is compelled to evolve toward industrial-ized and sustainable means and processes. Indeed, the Portland cement produc-tion alone is responsible for up to 8 % of global greenhouse gas emissions. In this context, concrete 3D printing demonstrates a significant potential for the reduction of material use. However, the majority of 3D printing materials dis-play a high cement content due to the rheological constraints associated with 3D printing along with the complexity of mix design. The present study proposes to integrate a parametric life cycle assessment cal-culation in the multi-objective optimization of a 3D printing mortar in order to minimize the environmental impact with a significantly reduced mix design workload. Applied to a limestone calcined clay blend, a genetic algorithm is used to decrease the climate change score while maintaining a set of rheological printability criteria predicted by artificial neural networks. As a result, this methodology allows the identification of locally optimized mixtures (up to 82wt% cement replacement) in as low as 9 additional formulations. Besides, as the process advances for an expanded design region, its efficiency is enhanced. This methodology is reproducible with locally sourced materials and for the majority of 3D printing materials, which are usually designed through empirical trial and error. This study introduces a systematic optimization process which establishes the sustainability at the core of its objectives and includes innovative tools for the formulation of cementitious materials. Digital Concrete 2024 - Supplementary Proceedings