Suchergebnisse

Urban trees and forests provide multiple ecosystem services (ES), including temperature regulation, carbon sequestration, and biodiversity. Interest in ES has increased amongst policymakers, scientists, and citizens given the extent and growth of urbanized areas globally. However, the methods and techniques used to properly assess biodiversity and ES provided by vegetation in urban environments, at large scales, are insufficient. Individual tree identification and characterization are some of the most critical issues used to evaluate urban biodiversity and ES, given the complex spatial distribution of vegetation in urban areas and the scarcity or complete lack of systematized urban tree inventories at large scales, e.g., at the regional or national levels. This often limits our knowledge on their contributions toward shaping biodiversity and ES in urban areas worldwide. This paper provides an analysis of the state-of-the-art studies and was carried out based on a systematic review of 48 scientific papers published during the last five years (2016–2020), related to urban tree and greenery characterization, remote sensing techniques for tree identification, processing methods, and data analysis to classify and segment trees. In particular, we focused on urban tree and forest characterization using remotely sensed data and identified frontiers in scientific knowledge that may be expanded with new developments in the near future. We found advantages and limitations associated with both data sources and processing methods, from which we drew recommendations for further development of tree inventory and characterization in urban forestry science. Finally, a critical discussion on the current state of the methods, as well as on the challenges and directions for future research, is presented. ; This work was financially supported by the Catalan Government through the fundinggrant ACCIÓ-Eurecat.

Fungi provide important forest ecosystem services worldwide. In Mediterranean pine forests, predicted warmer and drier conditions could lead to a decline in mushroom yields. Climate is a key factor regulating both tree growth and fungal yields, particularly in drought-prone Mediterranean ecosystems. However, the responses of forest growth and mushroom production to climate depend on the differences among tree and fungal species and functional groups (e.g., mycorrhizal vs. saprotrophic), forest types, as well as depending on site conditions. Here we investigate how climatic conditions drive seasonal wood formation (earlywood −EW− and latewood −LW− production) and mycorrhizal mushroom production, to disentangle if growth and fungal yields are related. This assessment was done in Mediterranean forests dominated by four pine species in two areas located in Catalonia (NE Spain) representing mesic and xeric conditions and encompassing wide ecological gradients. The data consisted of 7-year to 13-year long inventories of mushroom production. EW production was favoured by cold and wet climate conditions during the previous fall and winter, and during the current spring and summer. LW production was enhanced by warm and humid conditions from spring to early fall. Mushroom yield was improved by wet late-summer and fall conditions, mainly in the most xeric area. This study confirms the ample differences found in tree growth and fungal production along ecological and climatic gradients. Clear relationships between mycorrhizal fungal yields and tree growth were mostly observed in specific sites characterized by severe summer drought. Specifically, latewood production seems to be the tree-ring variable most tightly linked to mycorrhizal fungal yield in drought-prone areas. ; This study was partially funded by the research projects AGL2012-40035-C03-01 and AGL2015-66001-C3-1-R (Ministerio de Economía y Competitividad of Spain, Secretaría de Estado de Investigación, Desarrollo e Innovación), by the European project 'StarTree—Multipurpose trees and non-wood forest products: a challenge and opportunity' under grant agreement No. 311919. Irantzu Primicia work was supported by a STSM Grant from the COST Action FP1203 (European Non-Wood Forest Products). Sergio de Miguel's work was supported by the European Union's Horizon 2020 research and innovation programme within the framework of the MultiFUNGtionality Marie Skłodowska-Curie Individual Fellowship (IF-EF) under grant agreement No 655815.

Social-ecological systems in the Mediterranean Basin are characterised by high biodiversity and a prolonged cultural influence, leading to the co-evolution of these systems. The unique characteristics of Mediterranean social-ecological systems, current pressures leading to a decline in ecosystem services, and the need for coordinated action are recognised by policies promoting the protection and sustainable use of the region's heritage. Ecosystem assessments provide valuable information on the capacity of the Mediterranean Basin to ensure the well-being of its population. However, most assessments simplify the complexity of these systems, which may lead to inaccurate ecosystem services supply and flow estimations. This paper uses the Driver-Pressure-State-Impact-Response (DPSIR) model to guide an expert consultation that identifies the key characteristics of the Mediterranean social-ecological systems and analyses how these should be included in ecosystem assessments. Data collection was carried out through expert consultation with ecosystem services researchers. Multiple sources of complexity were identified, including the relationship between historical human activities, biodiversity spatio-temporal patterns, as well as the seasonal and long-term variability in ecosystem services. The importance of incorporating this complexity in ecosystem assessments for evidence-based decision-making is identified, suggesting that there is a need to adapt assessment approaches for the Mediterranean Basin social-ecological systems. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 809988. JVRD was supported by the Government of Asturias and FP7-Marie Curie-COFUND European Commission program (Grant 'Clarín' ACA17-02). SdM benefited from a Serra-Húnter Fellowship provided by the Generalitat of Catalonia.