Pre-construction quantification of embodied environmental impacts to promote sustainable construction projects: The case study of a diversion dam.

A quantitative assessment of the embodied environmental impacts of infrastructures can provide initial guidance to industry practitioners and engineers at the outset of the construction projects. This study presents the applicability of the Environmentally Extended Input-Output Analysis as a pre-construction evaluation tool for quantifying the embodied environmental impacts of a small diversion dam in Spain. Seven impact categories are assessed from a production-based and consumption-based perspective identifying the main sectors and regions contributing to the environmental impacts. From the consumption-based perspective, Spain is the only contributor to the environmental impacts, and from the production-based perspective, Spain is the main polluting country in all the impact categories contributing on average 68.9%. The use of high quantities of construction material leads to the sectors of steel and cement to significantly increase the environmental impacts. From the production-based perspective, steel and cement contribute on average 29.5% and 17.2%, respectively. From the consumption-based perspective, both sectors account for 74% of the overall environmental impacts. As observed in this case study, the application of the EEIOA model enables engineers and designers to focus during the early design stages on decisions that achieve high embodied impact reductions, such as prioritizing recycled materials for the construction of this infrastructure and, when possible, use materials from a less polluting origin.

Organization environmental footprint applying a multi-regional input-output analysis: A case study of a wood parquet company in Spain.

Wood has been presented as a carbon-neutral material capable of significantly contribute to climate change mitigation and has become an appealing option for the building sector. This paper presents the quantification of the organization environmental footprint of a wood parquet company. The multi-regional input-output (MRIO) database EXIOBASE was used with a further structural path analysis decomposition. The application of the proposed method quantifies 14 environmental impacts. Highly influential sectors and regions responsible for these impacts are assessed to propose efficient measures. For the parquet company studied, the highest impact category once normalized was ozone depletion and the dominant sector responsible for this impact was the chemical industry from Spain and China. The structural path decomposition related to ozone loss revealed that the indirect impacts embedded in the supply chain are higher than the direct impacts. It can be concluded that the assessment of the organizational environmental footprint can be carried out applying this well-structured and robust method. Its implementation will enable tracking of the environmental burdens through a company's supply chain at a global scale and provide information for the adoption of environmental strategies.

Understanding 'saturation' of radar signals over forests.

There is an urgent need to quantify anthropogenic influence on forest carbon stocks. Using satellite-based radar imagery for such purposes has been challenged by the apparent loss of signal sensitivity to changes in forest aboveground volume (AGV) above a certain 'saturation' point. The causes of saturation are debated and often inadequately addressed, posing a major limitation to mapping AGV with the latest radar satellites. Using ground- and lidar-measurements across La Rioja province (Spain) and Denmark, we investigate how various properties of forest structure (average stem height, size and number density; proportion of canopy and understory cover) simultaneously influence radar backscatter. It is found that increases in backscatter due to changes in some properties (e.g. increasing stem sizes) are often compensated by equal magnitude decreases caused by other properties (e.g. decreasing stem numbers and increasing heights), contributing to the apparent saturation of the AGV-backscatter trend. Thus, knowledge of the impact of management practices and disturbances on forest structure may allow the use of radar imagery for forest biomass estimates beyond commonly reported saturation points.