A multi-model assessment of ecosystem services in the Grenoble urban area

Les services écosystémiques (SE) ont reçu une attention croissante de la part de la communauté scientifique et des preneurs de décisions. Des approches multi-services ont été développées qui permettent de dresser un diagnostic environnemental, social et économique de territoires à plusieurs échelles. Révélant les variations spatiales individuelles de SE, les relations entre eux et l’existence de profils multi-services caractéristiques (‘bouquets’), ces études favorisent la communication entre acteurs et la gestion concertée. Pour permettre leur utilisation par le plus grand nombre, des plateformes multi-modèles permettent de fournir des estimations avec un minimum de données et d’efforts de modélisation. Des modèles plus performants existent par ailleurs mais leur coût de mise en œuvre plus élevé limite leur utilisation. Afin de répondre à une plus large palette de moyens et d’objectifs, des approches ‘par tiers’ sont donc maintenant développées.Nous présentons ici une suite de modèles génériques de SE, établis à partir de bases de données publiques et de ressources en ligne, et appliqués au cas du bassin de vie grenoblois. Ils permettent de caractériser un large éventail de services dans un territoire aux paysages et aux enjeux contrastés, tout en apportant des informations pertinentes quant aux différents aspects de planification.Nous présentons tout d’abord une suite de modèles génériques issus de la littérature et réappliqués à notre échelle. Ces modèles spatialement explicites et établis à partir de processus automatisés permettent une estimation rapide des stocks de carbone, de la prévention de l’érosion des sols, de la richesse spécifique des Vertébrés et du contrôle biologique.En réponse aux enjeux multiples de gestion des régions de montagne, nous avons développé un modèle de SE récréatif basé sur l’utilisation de traces GPS partagées sur les forums de sport. En intégrant ces données au modèle de Spectre d’Opportunité Récréative, nous avons obtenu une représentation spatiale fine de la fréquentation et de la multifonctionnalité récréative des écosystèmes.Dans une troisième partie, nous présentons une suite de modèles de SE fournis spécifiquement par les agrosystèmes. Nous avons tout d’abord établi un modèle spatialement explicite des paysages agricoles du territoire, à partir de données de télédétection et de statistiques agricoles. En couplant cette carte avec d’autres sources de données publiques et modèles biophysiques, nous avons pu évaluer les SE de production agricole, de maintien de la fertilité du sol, et de régulation de la qualité des eaux.A la lumière de ces résultats, nous examinons les implications d’utiliser au sein d’une approche multi-services une diversité de modèles issus de philosophies et de méthodologies différentes, fournissant des résultats aux niveaux d’incertitudes variables. Le regroupement d’informations contrastées dans une analyse commune interroge sur la complémentarité de ces modèles et le transfert des incertitudes à l’analyse générale. Au-delà des aspects strictement techniques, le but ultime de ces études étant d’informer les teneurs d’enjeux, un travail de communication doit donc être réalisé afin d’assurer un transfert cohérent des informations et des conclusions aux utilisateurs.Le travail présenté ici porte trois principales perspectives de développement. La mise en place d’un module informatique autonome du modèle de SE récréatif permettra sa diffusion directe à un large public. Deuxièmement, la suite de modèles servira de support pour une analyse des relations entre SE reflétant les enjeux du territoire : production agricole/efficience environnementale/biodiversité pour les agrosystèmes, hotspots récréatifs et de biodiversité dans les milieux ruraux et montagnards. L’analyse de projections selon des scénarios de développement du territoire permettra par la suite de tester la capacité de ces modèles à retourner des résultats pertinents en termes de planification.Ecosystem services (ES) have gained increased attention from both researchers and decision-makers in recent years. Multi-service approaches have been developed and applied at various spatial scales, allowing an environmental, social and economic diagnosis of territories. Disclosing spatial patterns of ecosystem services, untangling spatial and/or causal relationships between services, and revealing the existence of characteristic ‘service profiles’ (ES bundles), such studies have helped designing land planning options and fostering communication among stakeholders. To support such efforts, comprehensive modelling platforms have been created which can provide raw estimates of multiple ES with minimum data availability and modelling efforts. On the other hand, many accurate but highly specific and hardly reproducible methods remain inapplicable to most cases. Researchers are now challenged by a double objective: to develop generic and reproducible methods which can still provide relevant information in the context of the study area. In this direction, tier-based modelling approaches have been designed in order to offer answers adaptable to a variety of situations.Here we present a suite of generic ES models for the Grenoble living basin, a major urban area located at the foot of three mountain ranges and surrounded by large agricultural lowlands. By making relevant use of a variety of large-scale databases and online resources, these models characterize a large panel of biophysical aspects in a contrasted territory and yet provide relevant information for land planning concerns.We first present a suite of generic and spatially-explicit models built from national datasets or downscaled from larger studies using fully-automated processes, which provided estimates for carbon storage, prevention of soil erosion, Vertebrate species richness and biological control.Addressing the concerns associated with management of mountain areas for multiple objectives, we developed a model of recreation ES based on the use of GPS tracks downloaded from crowd-sourced websites. Integrated within a Recreation Opportunity Spectrum framework, this process allows a spatially-accurate assessment of both visitor presence and recreational multifunctionality.We then introduce a suite of SE provided by agrosystems. Building on the results of an analysis of teledetection images and agricultural statistics, we constructed a high-resolution map reflecting spatial patterns of crop systems, serving as a common base for modelling agricultural ES: production, maintenance of soil fertility, and regulation of water quality – assessed using additional public data sources and biophysical models.In the light of these results, we examine the implications of using models originating from several fields of research, each with its own philosophy, methodology, accuracy and data requirements, in multi-service approaches. The pooling of such information in a single analysis raises several questions, such as the complementarity of these models and the transfer of uncertainties from each single model to the whole study system. Beyond these technical aspects, the ultimate goal being to inform stakeholders, a communication work must therefore be carried out to efficiently convey the right messages from the expert to the user.This work presents three main development perspectives. The release of an autonomous module of the recreation model will favor its distribution to a larger public. Second, the suite of models will provide a relevant basis for analyzing spatial relationships between SE in accordance with local stakes: combined analyses of agricultural production, environmental efficiency and animal biodiversity in agrosystems, hotspot analyses of recreation SE and biodiversity in rural and mountain areas. Third, projection analyses according to scenarios of land use change will allow testing the capacity of these models to return relevant information for land planning

A GPS-based Recreation Ecosystem Service for the Grenoble Urban Area

National audienc

A GPS-based Recreation Ecosystem Service for the Grenoble Urban Area

International audienc

Benefits of crowd-sourced GPS information for modelling the recreation ecosystem service.

Modelling cultural ecosystem services is an enduring challenge, raising issues about the integration and spatialization of immaterial values and benefits, and their contingency on local preferences. Building on the Recreation Opportunity Spectrum framework, we present a novel methodology for assessing the recreation service using GPS tracks downloaded from crowd-sourced websites: the Grelou model (Georeferencing REcreation in Local OUtdoors), here applied to the Grenoble living area (French Alps). GPS tracks revealed the complete spatial extent of visitor presence and enabled modelling visitation networks for ten recreation activities with great spatial accuracy, thus providing a spatial estimate of recreational multifunctionality-expressed as the sum of networks. After coupling track networks with landscape preference and proximity factors, Grelou assessed the recreation service as a combination of opportunity and preferences, and identified recreation hotspots of different profiles such as aroundoor leisure or outdoor sport. We performed an online survey among local sports associations using an interactive map to select districts visited by respondents (~1000 people). The declared visitor presence for recreation purposes was highly spatially congruent with Grelou outputs (R2 = 0.89). Detailed analysis of responses on selection criteria for recreationists validates our choice of critical factors underlying both the recreation opportunity potential and the expected visitation frequency over the whole study area. We also analyzed outputs of the InVESt recreation model against the same visitation explanatory factors. Differences between the two models allowed us to pinpoint biases and weaknesses in the InVESt recreation modelling framework based on crowd-sourced photographs. By making use of an increasingly available data source (GPS tracks), Grelou offers a standardized and flexible way to assess the recreation service associated with multiple recreation practices. Its high spatial accuracy supports the analysis of spatial relationships with other ecoystems services and the integration of recreation into environmental assessments, land management and planning

A transdisciplinary assessment of future trajectories of land use and ecosystem services in the Grenoble region

International audienc

An interdisciplinary methodological guide for quantifying associations between ecosystem services

Considering the increasing uptake of the concept of "ecosystem services" in landscape management and environmental policies, it is urgent to establish a consensual framework to assess the complex relationships among ecosystem services, considering both the supply- and the demand-sides. A diversity of approaches have been proposed to evaluate ecosystem services associations, but not all methods are equivalent and methodological choices need to be made depending on the scientific and policy questions at hand, as well as the type of data available. Based on previous classifications of ecosystem service associations, we propose to characterize three broad types of associations considering the ecological (supply side) and socio-economical (demand side) aspects of ecosystem services: supply-supply, supply-demand and demand-demand. We then review quantitative methods available and propose guidelines to assess those three categories of relationships among ecosystem services and identify their explanatory variables following three steps: (i) detecting ecosystem services associations, (ii) defining bundles and (iii) identifying the explanatory variables of ecosystem services associations. For each step, strengths and weaknesses of different statistical analysis and machine learning methods are described. The proposed interdisciplinary methodological approach takes one step toward embracing such complexity of socio-ecological systems as it considers ecosystem services delivery (supply-supply), stakeholders' needs (demand-demand), and on how stakeholders can benefit from the ecosystem services delivery (supply-demand). We illustrate how such a diverse spectrum of methods may apply for land management

Data from: Assessing bundles of ecosystem services from regional to landscape scale: insights from the French Alps

1. Assessments of ecosystem services (ES) and biodiversity (hereafter ecological parameters) provide a comprehensive view of the links between landscapes, ecosystem functioning and human well-being. The investigation of consistent associations between ecological parameters, called bundles, and of their links to landscape composition and structure is essential to inform management and policy, yet it is still in its infancy. 2. We mapped over the French Alps an unprecedented array of 18 ecological parameters (16 ES and two biodiversity parameters) and explored their co-occurrence patterns underpinning the supply of multiple ecosystem services in landscapes. We followed a three-step analytical framework to i) detect the ES and biodiversity associations relevant at regional scale, ii) identify the clusters supplying consistent bundles of ES at subregional scale and iii) explore the links between landscape heterogeneity and ecological parameter associations at landscape scale. 3. We used successive correlation coefficients, overlap values and self-organizing maps to characterize ecological bundles specific to given land cover types and geographical areas of varying biophysical characteristics and human uses at nested scales from regional to local. 4. The joint analysis of land cover richness and ES gamma diversity demonstrated that local landscape heterogeneity alone did not imply compatibility across multiple ecosystem services, as some homogeneous landscape could supply multiple ecosystem services. 5. Synthesis and applications. Bundles of ecosystem services and biodiversity parameters are shaped by the joint effects of biophysical characteristics and of human history. Due to spatial congruence and to underlying functional interdependencies, ecological parameters should be managed as bundles even when management targets specific objectives. Moreover, depending on the abiotic context, the supply of multiple ecosystem services can arise either from deliberate management in homogeneous landscapes or from spatial heterogeneity

Mapping ecosystem services bundles in a heterogeneous mountain region

International audienceRecent institutional and policy frameworks prescribe the incorporation of ecosystem services (ES) into land use management and planning, favouring co-production of ES assessments by stakeholders, land planners and scientists. Incorporating ES into land management and planning requires models to map and analyze ES. Also, because ES do not vary independently, many operational issues ultimately relate to the mitigation of ES trade-offs, so that multiple ES and their interactions need to be considered. Using a highly accurate LULC database for the Grenoble urban region (French Alps), we mapped twelve ES using a range of models of varied complexity. A specific, fine-grained (less than 1 ha) LULC database at regional scale (4450 km²) added great spatial precision in individual ES models, in spite of limits of the typological resolution for forests and semi-natural areas. We analysed ES bundles within three different socio-ecosystems and associated landscape types (periurban, rural and forest areas). Such type-specific bundles highlighted distinctive ES trade-offs and synergies for each landscape. Advanced approaches combining remote sensing, targeted field data collection and expert knowledge from scientists and stakeholders are expected to provide the significant progress that is now required to support the reduction of trade-offs and enhance synergies between management objectives

Cartographier les services écosystémiques : quelles données, quels modèles, quelles incertitudes ? Exemple autour du bassin de vie de Grenoble

National audienceThe evolution of institutional and policy frameworks for Ecosystem Services (ES), especially thenew 2016 biodiversity legislation in France, make accounting for ES in land use managementmandatory. This requires the use of spatially explicit information, and therefore thedevelopment of models to map ES. Most models are based on or use Land Use or Land Cover maps(LU/LC) as a proxy. Using a highly accurate spatialized LU/LC database, we applied or adaptedmodels to map 15 ES. We show that depending on the implication of the LU/LC database as inputto the models, the type of model (proxy vs. process based) and the processes modeled, theresulting spatial patterns are more or less dependent on the LU/LC database. The critical analysisof limits and uncertainties in the LU/LC mapping process (in general and for our database inparticular), and the use of these maps for modelling ES showed : 1 - the benefits, especially inagricultural areas, of precise description and monitoring of LU/LC inter-annual dynamics for thequantification of ES supply ; 2- the consequences of LU/LC typological limits for thequantification of ES, especially in our work in forest and semi-natural areas. The use of remotesensing should support a serious typological improvement to better characterize the LU/LC andalso use as independent input data in ES models.L’évolution des cadres institutionnels et politiques autour de la question des ServicesEcosystémiques (SE), notamment avec la nouvelle loi Biodiversité en 2016 en France, amène à uneobligation de leur prise en compte dans la gestion territoriale. Cela nécessite l’utilisationd’informations spatialement explicites, et par conséquent le développement de modèlespermettant de cartographier les SE. La plupart des modèles se basent sur ou utilisent commeproxy des cartes d’Occupation ou d’Utilisation des Sols (OS/US). À partir d’une base de donnéesspatialisée extrêmement précise, nous avons appliqué ou adapté des modèles permettant decartographier 15 SE. Les résultats montrent que selon l’implication de la base de données d’OS/US en entrée dans les modèles, le type de modèle choisi (proxy vs. processus) et les processusmodélisés, les patrons spatiaux résultants sont plus ou moins dépendants de la carte d’OS/USd’entrée. L’analyse critique des limites et incertitudes inhérentes à la constitution des cartesd’OS/US (en général et la notre en particulier), ainsi que l’utilisation de ces cartes à des fins demodélisation de SE a montré : 1- les apports notamment dans les milieux agricoles d’unedescription précise des dynamiques interannuelles de l’OS/US pour la quantification de SEd’approvisionnement ; 2- l’implication de limites typologiques d’OS/US pour la quantification deSE, notamment dans notre travail pour les milieux forestiers et semi-naturels. L’usage de latélédétection apparait alors comme une piste sérieuse d’amélioration à la fois typologique pourmieux caractériser l’OS/US et également à utiliser comme donnée d’entrée indépendante dans lesmodèles de SE