Thomas Koellner

UNEP-SETAC guideline on global land use impact assessment on biodiversity and ecosystem services in LCA

PurposeAs a consequence of the multi-functionality of land, the impact assessment of land use in Life Cycle Impact Assessment requires the modelling of several impact pathways covering biodiversity and ecosystem services. To provide consistency amongst these separate impact pathways, general principles for their modelling are provided in this paper. These are refinements to the principles that have already been proposed in publications by the UNEP-SETAC Life Cycle Initiative. In particular, this paper addresses the calculation of land use interventions and land use impacts, the issue of impact reversibility, the spatial and temporal distribution of such impacts and the assessment of absolute or relative ecosystem quality changes. Based on this, we propose a guideline to build methods for land use impact assessment in Life Cycle Assessment (LCA).ResultsRecommendations are given for the development of new characterization models and for which a series of key elements should explicitly be stated, such as the modelled land use impact pathways, the land use/cover typology covered, the level of biogeographical differentiation used for the characterization factors, the reference land use situation used and if relative or absolute quality changes are used to calculate land use impacts. Moreover, for an application of the characterisation factors (CFs) in an LCA study, data collection should be transparent with respect to the data input required from the land use inventory and the regeneration times. Indications on how generic CFs can be used for the background system as well as how spatial-based CFs can be calculated for the foreground system in a specific LCA study and how land use change is to be allocated should be detailed. Finally, it becomes necessary to justify the modelling period for which land use impacts of land transformation and occupation are calculated and how uncertainty is accounted for.DiscussionThe presented guideline is based on a number of assumptions: Discrete land use types are sufficient for an assessment of land use impacts; ecosystem quality remains constant over time of occupation; time and area of occupation are substitutable; transformation time is negligible; regeneration is linear and independent from land use history and landscape configuration; biodiversity and multiple ecosystem services are independent; the ecological impact is linearly increasing with the intervention; and there is no interaction between land use and other drivers such as climate change. These assumptions might influence the results of land use Life Cycle Impact Assessment and need to be critically reflected.Conclusions and recommendationsIn this and the other papers of the special issue, we presented the principles and recommendations for the calculation of land use impacts on biodiversity and ecosystem services on a global scale. In the framework of LCA, they are mainly used for the assessment of land use impacts in the background system. The main areas for further development are the link to regional ecological models running in the foreground system, relative weighting of the ecosystem services midpoints and indirect land use.

Land use impacts on biodiversity in LCA: a global approach

PurposeLand use is a main driver of global biodiversity loss and its environmental relevance is widely recognized in research on life cycle assessment (LCA). The inherent spatial heterogeneity of biodiversity and its non-uniform response to land use requires a regionalized assessment, whereas many LCA applications with globally distributed value chains require a global scale. This paper presents a first approach to quantify land use impacts on biodiversity across different world regions and highlights uncertainties and research needs.MethodsThe study is based on the United Nations Environment Programme (UNEP)/Society of Environmental Toxicology and Chemistry (SETAC) land use assessment framework and focuses on occupation impacts, quantified as a biodiversity damage potential (BDP). Species richness of different land use types was compared to a (semi-)natural regional reference situation to calculate relative changes in species richness. Data on multiple species groups were derived from a global quantitative literature review and national biodiversity monitoring data from Switzerland. Differences across land use types, biogeographic regions (i.e., biomes), species groups and data source were statistically analyzed. For a data subset from the biome (sub-)tropical moist broadleaf forest, different species-based biodiversity indicators were calculated and the results compared.Results and discussionAn overall negative land use impact was found for all analyzed land use types, but results varied considerably. Different land use impacts across biogeographic regions and taxonomic groups explained some of the variability. The choice of indicator also strongly influenced the results. Relative species richness was less sensitive to land use than indicators that considered similarity of species of the reference and the land use situation. Possible sources of uncertainty, such as choice of indicators and taxonomic groups, land use classification and regionalization are critically discussed and further improvements are suggested. Data on land use impacts were very unevenly distributed across the globe and considerable knowledge gaps on cause–effect chains remain.ConclusionsThe presented approach allows for a first rough quantification of land use impact on biodiversity in LCA on a global scale. As biodiversity is inherently heterogeneous and data availability is limited, uncertainty of the results is considerable. The presented characterization factors for BDP can approximate land use impacts on biodiversity in LCA studies that are not intended to directly support decision-making on land management practices. For such studies, more detailed and site-dependent assessments are required. To assess overall land use impacts, transformation impacts should additionally be quantified. Therefore, more accurate and regionalized data on regeneration times of ecosystems are needed.

Toward Meaningful End Points of Biodiversity in Life Cycle Assessment

Halting current rates of biodiversity loss will be a defining challenge of the 21st century. To assess the effectiveness of strategies to achieve this goal, indicators and tools are required that monitor the driving forces of biodiversity loss, the changing state of biodiversity, and evaluate the effectiveness of policy responses. Here, we review the use of indicators and approaches to model biodiversity loss in Life Cycle Assessment (LCA), a methodology used to evaluate the cradle-to-grave environmental impacts of products. We find serious conceptual shortcomings in the way models are constructed, with scale considerations largely absent. Further, there is a disproportionate focus on indicators that reflect changes in compositional aspects of biodiversity, mainly changes in species richness. Functional and structural attributes of biodiversity are largely neglected. Taxonomic and geographic coverage remains problematic, with the majority of models restricted to one or a few taxonomic groups and geographic regions. On a more general level, three of the five drivers of biodiversity loss as identified by the Millennium Ecosystem Assessment are represented in current impact categories (habitat change, climate change and pollution), while two are missing (invasive species and overexploitation). However, methods across all drivers can be greatly improved. We discuss these issues and make recommendations for future research to better reflect biodiversity loss in LCA.

Principles for life cycle inventories of land use on a global scale

PurposeTo assess the diverse environmental impacts of land use, a standardization of quantifying land use elementary flows is needed in life cycle assessment (LCA). The purpose of this paper is to propose how to standardize the land use classification and how to regionalize land use elementary flows.Materials and methodsIn life cycle inventories, land occupation and transformation are elementary flows providing relevant information on the type and location of land use for land use impact assessment. To find a suitable land use classification system for LCA, existing global land cover classification systems and global approaches to define biogeographical regions are reviewed.Results and discussionA new multi-level classification of land use is presented. It consists of four levels of detail ranging from very general global land cover classes to more refined categories and very specific categories indicating land use intensities. Regionalization is built on five levels, first distinguishing between terrestrial, freshwater, and marine biomes and further specifying climatic regions, specific biomes, ecoregions and finally indicating the exact geo-referenced information of land use. Current land use inventories and impact assessment methods do not always match and hinder a comprehensive assessment of land use impact. A standardized definition of land use types and geographic location helps to overcome this gap and provides the opportunity to test the optimal resolution of land cover types and regionalization for each impact pathway.Conclusions and recommendationThe presented approach provides the necessary flexibility to providers of inventories and developers of impact assessment methods. To simplify inventories and impact assessment methods of land use, we need to find archetypical situations across impact pathways, land use types and regions, and aggregate inventory entries and methods accordingly.

Land Use in Life Cycle Assessment: Global Characterization Factors Based on Regional and Global Potential Species Extinction

Land use is one of the main drivers of biodiversity loss. However, many life cycle assessment studies do not yet assess this effect because of the lack of reliable and operational methods. Here, we present an approach to modeling the impacts of regional land use on plants, mammals, birds, amphibians, and reptiles. Our global analysis calculates the total potential damage caused by all land uses within each WWF ecoregion and allocates this total damage to different types of land use per ecoregion. We use an adapted (matrix-calibrated) species-area relationship to model the potential regional extinction of nonendemic species caused by reversible land use and land use change impacts. The potential global extinction of endemic species is used to assess irreversible, permanent impacts. Model uncertainty is assessed using Monte Carlo simulations. The impacts of land use on biodiversity varied strongly across ecoregions, showing the highest values in regions where most natural habitat had been converted in the past. The approach is thus retrospective and was able to highlight the impacts in highly disturbed regions. However, we also illustrate how it can be applied to prospective assessments using scenarios of future land use. Uncertainties, modeling choices, and validity are discussed.

Biodiversity, Ecosystem Function, and Investment Risk

ABSTRACT Biodiversity has the potential to influence ecological services. Management of ecological services thus includes investments in biodiversity, which can be viewed as a portfolio of genes, species, and ecosystems. As with all investments, it becomes critical to understand how risk varies with the diversity of the portfolio. The goal of this article is to develop a conceptual framework, based on portfolio theory, that links levels of biodiversity and ecosystem services in the context of risk-adjusted performance. We illustrate our concept with data from temperate grassland experiments conducted to examine the link between plant species diversity and biomass production or yield. These data suggest that increased plant species diversity has considerable insurance potential by providing higher levels of risk-adjusted yield of biomass. We close by discussing how to develop conservation strategies that actively manage biodiversity portfolios in ways that address performance risk, and suggest a new empirical research program to enhance progress in this field.

Land use impacts on freshwater regulation, erosion regulation, and water purification: a spatial approach for a global scale level

PurposeRarely considered in environmental assessment methods, potential land use impacts on a series of ecosystem services must be accounted for in widely used decision-making tools such as life cycle assessment (LCA). The main goal of this study is to provide an operational life cycle impact assessment characterization method that addresses land use impacts at a global scale by developing spatially differentiated characterization factors (CFs) and assessing the extent of their spatial variability using different regionalization levels.MethodsThe proposed method follows the recommendations of previous work and falls within the framework and principles for land use impact assessment established by the United Nations Environment Programme/Society of Environmental Toxicology and Chemistry Life Cycle Initiative. Based on the spatial approach suggested by Saad et al. (Int J Life Cycle Assess 16: 198–211, 2011), the intended impact pathways that are modeled pertain to impacts on ecosystem services damage potential and focus on three major ecosystem services: (1) erosion regulation potential, (2) freshwater regulation potential, and (3) water purification potential. Spatially-differentiated CFs were calculated for each biogeographic region of all three regionalization scale (Holdridge life regions, Holdridge life zones, and terrestrial biomes) along with a nonspatial world average level. In addition, seven land use types were assessed considering both land occupation and land transformation interventions.Results and discussionA comprehensive analysis of the results indicates that, when compared to all resolution schemes, the world generic averaged CF can deviate for various ecosystem types. In the case of groundwater recharge potential impacts, this range varied up to factors of 7, 4.7, and 3 when using the Holdridge life zones, the Holdridge regions, and the terrestrial biomes regionalization levels, respectively. This validates the importance of introducing a regionalized assessment and highlights how a finer scale increases the level of detail and consequently the discriminating power across several biogeographic regions, which could not have been captured using a coarser scale. In practice, the implementation of such regionalized CFs suggests that an LCA practitioner must identify the ecosystem in which land occupation or transformation activities occur in addition to the traditional inventory data required—namely, the land use activity and the inventory flow.ConclusionsThe variability of CFs across all three regionalization levels provides an indication of the uncertainty linked to nonspatial CFs. Among other assumptions and value choices made throughout the study, the use of ecological borders over political boundaries was deemed more relevant to the interpretation of environmental issues related to specific functional ecosystem behaviors.

Land use impacts on biodiversity in LCA: proposal of characterization factors based on functional diversity

PurposeThe focus of land use modeling in life cycle impact assessment has been mainly on taxonomic measures of biodiversity, namely species richness (SR). However, increasing availability of trait data for species has led to the use of functional diversity (FD) as a promising metric to reflect the distinctiveness of species; this paper proposes the use of an FD index to calculate characterization factors (CFs) for land use impacts. Furthermore, we compare the results of the CFs to current practice and assess the increase in complexity introduced by the use of the new indicator.MethodsThe model proposed is based on data compiled by previous regional meta-analysis on SR and FD, in different land use types in the Americas. The taxonomic groups included were mammals, birds, and plants. Within each study, calculated values for FD for different land use types were compared with the natural or close-to-natural state, taken as the reference situation. FD values among different land uses were standardized, and CFs were calculated. The final results were then analyzed and compared by analysis of variance and post hoc tests. A sensitivity analysis was also applied to verify the influence on the choice of the reference state.Results and discussionThe results show that significant differences exist between CFs for SR and FD metrics. Across all taxa, CFs differ significantly between land use types. The results support the use of CF for FD, as a complement to current practice. Distinct CFs should be applied for at least six groups of land use categories. The choice of reference land use type did not significantly alter the results but can be a source of variability. A sensitivity analysis evaluating the impact of alternate land use types as reference types found only few significant changes on the results.Conclusions and recommendationsGiven the results, we believe the use of CFs based on FD can help on the establishment of possible links between species loss and key ecosystem functions, i.e., on the association between the midpoint indicator (e.g., biodiversity loss) and the damage caused to ecosystem quality, in terms of functions lost. Basing CFs on FD is not without challenges. Such indices are data hungry (requiring species composition and traits) require more complex calculations than current common practice, including decisions on the choice of a method to calculate FD and the selection of traits.

Global land use impact assessment on biodiversity and ecosystem services in LCA

Landuseandlandusechangehavesevereeffectsonbiodiver-sityandthecapacityofecosystemstodeliverservices,suchasbiomass production or water filtration. Whereas research onimpacts of land use on biodiversity is a well-established field,research on ecosystem services motivated by Daily (1997)isless developed, but steadily catching up. The MillenniumEcosystem Assessment (2005) on ecosystem changes hasbegun to address this gap and has highlighted the impor-tance of nature’s services for human well-being. Meanwhile,operational assessment methods support decision-makers inplanning and optimizing landscapes with respect to biodi-versity and multiple ecosystem services (Chan et al. 2006;Daily et al. 2009; Groot et al. 2010;Maesetal.2012).However, until now, those methodologies have mainlyfocused on regional systems with distinct spatial boundaries.However, the ecological assessment of land use in productsystems requires a global approach.The basic motivation for this special issue is to integratelanduseimpactsonbiodiversityandecosystemservices intolife cycleassessment (LCA), toallowamore comprehensiveimpact assessment of globally distributed product systems.The work builds on the key elements for land use impactassessment within LCA that was developed in the phase 1 ofthe UNEP-SETAC Life Cycle Initiative (Mila i Canals et al.2007). The methodology presented here is the outcome oftheprojectLULCIAwithinthephase2oftheUNEP-SETACLife Cycle Initiative. The main contributors to the projecthave been PES, University of Bayreuth, Germany (ThomasKoellner), SEAC, Unilever, UK (Llorenc Mila i Canals),European Commission, Joint Research Centre, Italy(Miguel Brandao and Danielle Maia de Souza), NSSI, ETHZurich, Switzerland (Laura de Baan), IWOE, University ofSt. Gallen, Switzerland (Ruedi Muller-Wenk), CIRAIG,Canada (Manuele Margni and Rosie Saad), LBP-GaBi,University of Stuttgart, Germany (Ulrike Bos, Tabea Beck,Jan-Paul Lindner and Bastian Wittstock), and CLIOPE,Facultad Regional Mendoza, Universidad TecnologicaNacional, Argentina (Barbara Civit). After a long processof consensus building on framing the methodology, weachieved an operational LCIA method to assess the use ofland anywhere on the globe (Koellner et al. 2013b)anddevelopedasetofcharacterizationfactorsthatallowslinkingspatially explicit land use elementary flows of occupationand transformation (Koellner et al. 2013a) to impacts onbiodiversity (de Baan et al. 2013; Souza et al. 2013) andservices provided by terrestrial ecosystems (Muller-Wenkand Brandao 2010; Beck et al. 2010; Brandao and Mila iCanals 2013; Saad et al. 2013). These characterization fac-tors were tested in a food case study (Mila i Canals et al.2013). With this special issue, certainly not all problemsrelated to the assessment of land use impacts on biodiversityandecosystemservicesonaglobalscalecouldbesolved.Wesee the following five major outstanding questions relevantfor future research to improve the assessment of biodiversityand ecosystem services in LCA:How to combine generic impact assessment with site-specificassessments? Although uncertainties of the current modelsare large they allow for the identification of potential prob-lem areas related to land use impacts in the backgroundsystem of a product and minimize the risk of problemshifting. However, such a generic assessment on a globalscale cannot replace on-site assessment of ecosystems.Therefore, site-specific characterization factors for the

Factors Influencing Households' Firewood Consumption in the Western Pamirs, Tajikistan

Abstract Firewood is a major energy source, especially in many high mountainous regions in developing countries where other energy sources are limited. In the mountainous regions of Tajikistan, current energy consumption is limited owing to geographic isolation and numerous challenges—including in the energy sector—that emerged after the collapse of the Soviet Union and Tajikistans independence. The sudden disruption of external supplies of energy forced people to rely on locally available but scarce biomass resources, such as firewood and animal dung. We conducted an empirical study to gain an understanding of current household energy consumption in the Western Pamirs of Tajikistan and the factors that influence firewood consumption. For this purpose, we interviewed members of 170 households in 8 villages. We found that, on average, households consumed 355 kg of firewood, 253 kWh of electricity, 760 kg of dung, and 6 kg of coal per month in the winter of 2011–2012. Elevation, size of a households private garden, and total hours of heating had a positive relationship with firewood consumption, and education level and access to a reliable supply of electricity showed a negative relationship.