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Ecosystems are valuable as well as aesthetic. The natural functions of ecosystems can have profound effects on the economy, and human and wildlife health. The aggregate value of these 'ecosystem services' may far exceed the economic value derived from resource extraction or industrial development, especially when considering the costs of restoring ecosystems. There is increasing interest, therefore, in monitoring and protecting ecosystems, and accounting for the biodiversity and services they provide. In 2010, Canada undertook a review of ecosystem status and trends that identified the regions and ecosystems where management is most urgently needed. The authors concluded that more large-scale, long-term, standardized, and spatially complete information is needed for effective monitoring and management. Satellite-based earth observation (EO) tools were seen as a means of addressing this information need. In a separate exercise, a list of priority questions for conservation policy and management at a national level was produced: the resolution of three-quarters of those questions appears to depend on EO tools to a significant or critical extent. Canada has a long and successful history in all aspects of earth observation, placing it amongst the leaders in the international remote sensing community. Whereas the need for measuring ecosystem services to humans and wildlife is increasingly important, the challenges for doing so are increasingly significant and the technology required is increasingly complex. Overcoming these challenges is necessary to address emerging conservation priorities including measurement of ecosystem attributes to support habitat conservation for Species at Risk, measuring functional capacity of ecosystems to mitigate effects of climate change, monitoring and mitigating effects of resource extraction, and supporting industrial development in Canada's north. Addressing emerging priorities requires dialogue among ecologists and decision makers, coordinated at regional and national scales, and requires drawing on the best EO technologies and infrastructure available. This review highlights the urgency of a coordinated approach for innovative applications of EO tools toward conservation and discusses some of the key elements that might be included and opportunities and challenges that might be encountered, by such an approach. Key words: ecosystem monitoring, ecosystem services, ecosystem function, earth observation, remote sensing, Canada. Les ecosystemes sont utiles et esthetiques. Les fonctions naturelles des ecosystemes peuvent exercer de profonds effets sur l'economie ainsi que sur la sante humaine et faunique. La valeur agregee des services rendus par ces ecosystemes depasse largement la valeur economique provenant de l'extraction des ressources ou du developpement industriel, surtout lorsque l'on considere les couts pour la restauration des ecosystemes. On observe consequemment un interet croissant pour le suivi et la protection des ecosystemes, ainsi que pour la prise en compte de la biodiversite et des services qu'ils rendent. En 2010, le Canada a entrepris une revue de l'etat des ecosystemes et des tendances identifiant les regions et les ecosystemes ou le besoin en amenagement devient le plus urgent. Les auteurs concluent que pour assurer le suivi et l'amenagement efficace, on doit reunir plus d'information standardisee et complete dans l'espace, a grande echelle et a long terme. Les outils d'observation de la terre par satellite (EO) apparaissent comme le moyen pour combler ce besoin d'information. Dans un exercice distinct, les auteurs ont produit une liste de questions prioritaires pour les politiques de conservation et l'amenagement a l'echelle nationale : il semble que la reponse a trois quarts de ces questions depende des outils EO de facon significative ou critique. Le Canada possede une longue histoire de succes dans tous les aspects de l'observation de la terre, le situant parmi les meneurs mondiaux de la communaute internationale en teledetection. Alors que le besoin de mesurer les services des ecosystemes pour les humains et pour la faune devient de plus en plus important, les defis pour le rencontrer deviennent de plus en plus significatifs et les technologies necessaires se complexifient. Il est necessaire de surmonter ces defis afin de faire face aux priorites emergentes de conservation: mesure des caracteristiques des ecosystemes pour supporter la conservation des especes a risque; mesure de la capacite fonctionnelle des ecosystemes a mitiger les effets de l'extraction des ressources; et, support au developpement industriel du Nord canadien. Rencontrer les priorites emergentes requiert un dialogue entre les ecologistes et les decideurs, coordonne a l'echelle regionale aussi bien que nationale, et necessite une planification sur les meilleures technologies et infrastructures EO disponibles. Cette revue souligne l'urgence d'une approche coordonnee pour assurer des applications innovantes des outils EO en vue de la conservation et discute certains elements cles qui pourraient etre inclus ainsi que les opportunites et les defis qu'on pourrait rencontrer, en prenant une telle approche. [Traduit par la Redaction] Mots-cles: suivi des ecosystemes, sevices des ecosystemes, fonction des ecosystemes, observation de la terre, teledetection, Canada., Status, trends, and management of Canadian ecosystems Ecosystems are often described in terms of their composition (e.g., what species and what landscape components are present), configuration (e.g., how things are [...]

This paper presents development of a multivariate forest structural complexity index based on relationships between field-based structural variables and geospatial data. Remote sensing has been widely used to model individual forest structural attributes at many scales. As opposed to, or in addition to, individual structural parameters such as leaf area index or tree height, overall structural complexity information can enhance forest inventories and provide a variety of information to forest managers, including identifying damage and disturbance as well as indicators of habitat or biodiversity. In this study, a multivariate modelling technique, redundancy analysis, was implemented to derive a model incorporating both horizontal and vertical structural attributes as predicted by an ensemble of high-resolution multispectral airborne imagery and topographic variables. The first redundancy analysis axis of the final model explained 35% of the total variance of the field variables and was used as the complexity index. With a root mean squared error of 19.9%, the model was capable of differentiating four to five relative levels of complexity. This paper presents the forest ecological and modelling aspects of the research. A related paper presents the remote sensing aspects, including application of the model to map predicted structural complexity, map validation, and testing of the method at multiple scales. Resume: Cet article presente le developpement d'un indice multivarie de complexite de la structure de la foret base sur les relations entre des variables structurales mesurees sur le terrain et des donnees geospatiales. La teledetection a ete largement utilisee pour modeliser les attributs structuraux de la foret a plusieurs echelles. Contrairement a, ou en plus, des parametres structuraux individuels comme l'indice de surface foliaire ou la hauteur des arbres, une information globale au sujet de la complexite structurale peut ameliorer les inventaires forestiers et fournir une variete de renseignements aux amenagistes forestiers, incluant l'identification des dommages et des perturbations aussi bien que des indicateurs d'habitat ou de biodiversite. Dans cette etude, une technique de modelisation multivariee, l'analyse de redondance, a ete appliquee pour deriver un modele qui incorpore des attributs, tant horizontaux que verticaux de la structure, predits par un ensemble d'images aeriennes multispectrales a haute resolution et des variables topographiques. Le premier axe de l'analyse de redondance du modele final expliquait 35% de la variance totale des variables terrain et a ete utilise comme indice de complexite . Avec une erreur quadratique moyenne de 19,9 %, le modele etait capable de differencier quatre a cinq niveaux de complexite. Cet article presente les aspects de la recherche relies a la modelisation et a l'ecologie forestiere. Un autre article presente les aspects relies a la teledetection, incluant l'application du modele pour cartographier la complexite structurale predite, la validation de la cartographie et l'essai de la methode a plusieurs echelles. [Traduit par la Redaction], Introduction Understanding patch-level structural variations across a forest can enhance inventories and provide important information to forest managers. Specifically, information with respect to damage and disturbance (e.g., Cosmopoulos and King [...]

Abstract: Modelling and mapping of hooded warbler (Wilsonia citrina) nesting habitat in forests of southern Ontario were conducted using Ikonos and Landsat data. The study began with an analysis of skyward hemispherical photography to determine canopy characteristics associated with nest sites. It showed that nest sites had significantly less overhead canopy cover and larger maximum gap size than in non-nest areas. These findings led to the hypothesis that brightness variability in high to moderate resolution remotely sensed imagery may be greater at nest sites than in non-nest areas due to larger shadows and greater shadow variability related to these gap characteristics. This was confirmed when, in addition to some spectral band brightness variables, several image texture and spectrally unmixed fraction (shadow, bare soil) variables were found to be significantly different for nest and non-nest sites in Ikonos and Landsat imagery. These significantly different variables were used in maximum likelihood classification (MLC) and logistic regression (LR) to produce maps of potential nesting habitat. Mapping was conducted with Ikonos and Landsat in a local area where most known nest sites occur, and regionally using Landsat data for almost all of the hooded warbler range in southern Ontario. For the local area mapping using Ikonos data, a posteriori probabilities for both the MLC and LR methods showed that about 62% of the nest sites set aside for validation had been classified with high probability (p >0.70) in the nest class. MLC mapping accuracy was 70% for the validation nest sites and 87% of validation nest sites were within 10 m of classified nesting habitat, a distance approximately equivalent to expected positional error in the data. LR accuracy was slightly lower. Nest site MLC mapping accuracy in the local area using Landsat data was 87% but the map was much coarser due to the larger pixel size. Regional mapping with Landsat imagery produced lower classification accuracy due to high errors of commission for the habitat class. This resulted from a poor spatial distribution and low number of observations of nest sites throughout the region compared to the local area, while the non-nest site data distribution was too narrow, having been defined and assessed (using standard accepted methods) as areas with no ground shrubs. If either of these problems can be ameliorated, regional mapping accuracy may improve. [Copyright &y& Elsevier]