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The article discusses the significance of the 11th International Association for Landscape Ecology (IALE) World Congress, which took place in Africa for the first time in July 2023. It highlights the unique perspectives and challenges faced by the African landscape ecology community and emphasizes the importance of fostering collaborations within the Global South. The article also discusses the evolving topics in landscape ecology, such as climate change and sustainability, and the need for a more inclusive dialogue in the field. It concludes by discussing the role of the journal Landscape Online in promoting diversity and facilitating scientific discourse between the Global North and South. [Extracted from the article]

In forested systems throughout the world, climate influences tree growth and aboveground net primary productivity (ANPP). The effects of extreme climate events (i.e., drought) on ANPP can be compounded by biotic factors (e.g., insect outbreaks). Understanding the contribution of each of these influences on growth requires information at multiple spatial scales and is essential for understanding regional forest response to changing climate. The mixed conifer forests of the Lake Tahoe Basin, California and Nevada, provide an opportunity to analyze biotic and abiotic influences on ANPP. Our objective was to evaluate the influence of moisture stress (climatic water deficit, CWD) and bark beetles on basin-wide ANPP from 1987 to 2006, estimated through tree core increments and a landscape simulation model (LANDIS-II). Tree ring data revealed that ANPP increased throughout this period and had a nonlinear relationship to water demand. Simulation model results showed that despite increased complexity, simulations that include moderate moisture sensitivity and bark beetle outbreaks most closely approximated the field-derived ANPP--CWD relationship. Although bark beetle outbreaks and episodic drought-induced mortality events are often correlated, decoupling them within a simulation model offers insight into assessing model performance, as well as examining how each contributes to total declines in productivity. Key words: ANPP, net ecosystem production, increment cores, forest simulation model, LANDIS-II. Dans les ecosystemes forestiers partout dans le monde, le climat influence la croissance des arbres et la productivity primaire nette aerienne (PPNA). Les effets d'evenements climatiques extremes (c.-a-d. la secheresse) sur la PPNA peuvent etre aggraves par des facteurs biotiques (p. ex. des epidemies d'insectes). Pour comprendre la contribution de chacune de ces influences sur la croissance requiert de l'information a de multiples echelles spatiales et cela est essentiel pour comprendre la reaction regionale de la foret au changement climatique. Les forets melangees de coniferes du bassin du lac Tahoe, en Californie et au Nevada, fournissent une occasion d'analyser l'influence des facteurs biotiques et abiotiques sur la PPNA. Notre objectif consistait a evaluer l'influence du stress hydrique (deficit hydrique climatique, DHC) et des scolytes sur la PPNA a l'echelle d'un bassin de 1987 a 2006. La PPNA a ete estimee a l'aide de carotte prelevees sur des arbres et d'un modele de simulation du paysage (LANDIS-II). Les donnees dendrometriques revelent que la PPNA a augmente durant cette periode et qu'elle avait une relation non lineaire avec la demande en eau. Les resultats du modeles indiquent que, malgre l'augmentation de la complexite, les simulations qui incluent un niveau modere de sensibilite a l'humidite et les epidemies de scolytes produisent la plus proche approximation de la relation entre la PPNA et le DHC derivee a partir de donnees terrain. Bien que les epidemies de scolytes et la mortalite episodique induite par la secheresse soient souvent correlees, le fait de les decoupler dans un modele de simulation fournit des renseignements pour evaluer la performance du modele ainsi que pour examiner de quelle facon chaque facteur contribue au declin total de la productivite. [Traduit par la Redaction] Mots-cles: PPNA, production nette de l'ecosysteme, carottes de sondage, modele de simulation forestiere, LANDIS-II., Introduction Forests are an integral component of the global carbon (C) cycle, sequestering approximately 30% of annual anthropogenic C emissions (Pan et al. 2011a). Estimates of forest C dynamics are [...]