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• We present the first full review of research pertaining a water planetary boundary. • Initial shortcomings of the water planetary boundary have partly been resolved. • Input-output analysis may facilitate investigation into the exceedance of boundaries. • Spatiotemporal mismatches amid input-output and hydrological data pose a challenge. The water planetary boundary has been proposed to determine limits for a sustainable anthropogenic appropriation of freshwater. Aim of the present research was to summarise the water planetary boundary's development status and applications including its integration into Life Cycle Assessment and Environmentally-Extended Input-Output-Analysis. A systematic literature review was conducted for studies featuring the keywords "planetary boundary" and "water consumption". All pertinent studies were categorised as either revision, commentary, stand-alone application, the application within Life Cycle Assessment or application within Environmentally-Extended Input-Output Analysis and subsequently summarised and discussed. Overall, 35 studies from the period of 2009 until mid-2020 are subject of this review. Recent advancements such as spatially differentiated thresholds and refined sub-boundaries have addressed initial shortcomings of the concept of a water planetary boundary. Stand-alone applications of the water planetary boundary have either established local thresholds or allocated fair shares of afore-defined global thresholds. Several authors integrated the concept of a water planetary boundary into LCA e.g. via characterisation factors, weighting or normalisation, often under consideration of sharing principles. An application of the water planetary boundary into Environmentally-Extended Input-Output Analysis is less represented although some authors have demonstrated its powerfulness in investigating causes for the exceedance of local thresholds. For some of the reviewed studies, a link to the water planetary boundary remains rather vague as these studies merely investigate water availability in comparison to consumption. Although it should be applied with caution, the concept of a planetary boundary for freshwater use can contribute to understanding limits to sustainable freshwater consumption. Many studies established water use thresholds but refrained from analysing causative drivers in detail. Challenges for exploring this further include overcoming spatial and temporal mismatches of environmentally-extended economic accounts and hydrogeological data. [ABSTRACT FROM AUTHOR]

Abstract Evaluating the impacts on biodiversity by means of the life cycle assessment (LCA) is a task researchers are currently facing. One impact assessment method that aims to do so is the recently developed biodiversity impact assessment BIA+. The aim of the present paper is to test this method and to show its applicability and feasibility. Additionally opportunities and challenges of this method shall be revealed. For this purpose, a case study for assessing the impacts of biodiesel production on freshwater biodiversity is introduced. Two substances, namely phosphorus and 1,4-dichlorobenzene (DCB), which are used for the biodiesel production for fertilization and the usage of pesticides, are being considered. The inventory data needed for the case study is gathered through the grey water footprint of the crop production that forms the basis of the European biodiesel consumption. Further, the BIA+ method is applied in order to assess the impacts of the biodiesel consumption in Europe for the year 2010 on freshwater biodiversity. The results reveal that even though assumptions have to be made and the results are highly uncertain, this method helps to identify hotspots within production processes. By including the BIA+ as an impact assessment method into LCA, impacts of products can be assessed with regard to biodiversity including genetic, species and ecosystem diversity. The main impact hotspot occurs in France with a potential loss of the biodiversity of 0.5 points. The lowest loss of the biodiversity occurs in Brazil (loss of 8.05*10–06 points). The results are mainly influenced by the impact of the toxic substance 1,4-DCB. By means of the case study, it is shown that the BIA+ method is applicable. [ABSTRACT FROM AUTHOR]

Water footprinting has emerged as an important approach to assess water use related effects from consumption of goods and services. Assessment methods are proposed by two different communities, the Water Footprint Network (WFN) and the Life Cycle Assessment (LCA) community. The proposed methods are broadly similar and encompass both the computation of water use and its impacts, but differ in communication of a water footprint result. In this paper, we explain the role and goal of LCA and ISO-compatible water footprinting and resolve the six issues raised by Hoekstra (2016) in “A critique on the water-scarcity weighted water footprint in LCA”. By clarifying the concerns, we identify both the overlapping goals in the WFN and LCA water footprint assessments and discrepancies between them. The main differing perspective between the WFN and LCA-based approach seems to relate to the fact that LCA aims to account for environmental impacts, while the WFN aims to account for water productivity of global fresh water as a limited resource. We conclude that there is potential to use synergies in research for the two approaches and highlight the need for proper declaration of the methods applied. [ABSTRACT FROM AUTHOR]