Influence of natural and anthropogenic variables on natural capital and environmental flows within coastal marine ecosystems: a case study of Italy
Ilaria Rigo
The natural capital that characterizes coastal ecosystems must be protected: it maintains the environment itself and provides ecosystem services necessary to human health and well-being. In recent decades, the need to preserve natural capital has become increasingly interesting for environmental policies and biodiversity conservation strategies by the European Union (Natural Capital Committee, 2021). In this regard, this study proposes a quantification and a spatial distribution assessment of natural capital and environmental flows within the coastal marine habitats of the Ligurian Sea (Mediterranean Sea-NW Italy). For this purpose emergy analysis was applied, following the environmental accounting model for the Italian Marine Protected Areas (Vassallo et al., 2017; Paoli et al., 2018), to identify resources along with the coastal areas and to have a system functioning view. Furthermore, to ensure sustainable management of the area and understand how the system is able to withstand any pressures, some natural and anthropogenic variables were identified. Moreover, the possible influence of variables on the ability of the natural system to generate natural capital and environmental flows was verified through a regression analysis (Random Forest) and questionnaires administered to experts in the coastal studies (Delphi method). In both cases, four different predictive scenarios, depending on the variable type, were created to investigate how much the variables can influence natural capital and flows values. This research permits to outline of the current state of Ligurian coastal marine habitats and represents an environmental management tool supporting policy makers in decision-making processes in coastal areas.
Embodied carbon: Accounting for the work of the bio-geosphere in construction materials
Miaomiao Hou, William W. Braham, Suryakiran Prabhakaran, David Tilley
Abstract: Buildings are a central tool of the fuel-powered civilization that has released carbon dioxide and other greenhouse gases into the atmosphere over the last century, dramatically exceeding the ability of the bio-geosphere to process the waste and change the climate as it accumulates. At least one-quarter of these emissions are associated with building materials and construction and are called “embodied carbon.” Current methods for evaluating embodied carbon track the inputs and emissions from human production processes, discounting or neglecting the work of the bio-geosphere to prepare and deliver materials and absorb wastes. This paper uses the method of emergy synthesis (with an “m”) to account for the environmental cost of absorbing or neutralizing the greenhouse gas emission associated with construction materials. We adapted Life Cycle Inventories (LCI) data for emergy synthesis and applied them to a selection of typical construction materials and floor systems for comparative study with the same functional unit. In addition to the “upstream” work needed to provide a resource, the method also includes the “downstream” costs of atmospheric emissions, specifically the work of neutralizing carbon dioxide or diluting other pollutants to yield a complete assessment of embodied carbon. The results reinforce a critical distinction between biogenic and earth materials revealed in the conventional analysis of global warming and further demonstrate the importance of the treatment (e.g. reuse and recycling) of these materials when buildings are demolished. The expanded accounting approach adds to our abilities to analyze the emergy associated with waste streams.
Emergy-based sustainability evaluation of Erhai Lake Basin in China
Shaozhuo Zhong
Abstract: Rapid economic development has significantly degraded the environmental quality of Erhai Lake and its basin. In order to assess the present sustainability of the Erhai Lake Basin and suggest improvement options, this study built an emergy-based framework, in which the whole basin system comprises five subsystems. And decomposition analysis was used to identify driving forces. Especially, the performance of water resources was analyzed considering the vital role of lake water in basin development. The results of emergy-based indicators, e.g. EYR (1.31), ELR (60.98)and ESI (2.15E-02), revealed that the whole basin is far away from sustainable development. The key factor is the strong reliance on nonrenewable resources, especially in the form of purchased resources (76.48% of total emergy used). Regarding water consumption, agriculture is the dominant sector by volume, but with a low use efficiency, while industrial water use as the largest environmental impact due to its high water quality requirement. Policy insights for improving the overall sustainability of the Erhai Lake Basin are proposed, including adjusting industrial structure and promoting a circular economy, facilitating green agriculture, improving water efficiency and increasing renewable energy use.