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As the climate continues to warm and the world becomes more urbanized, our reliance on trees and the benefits they provide is rapidly increasing. Many cities worldwide are planting trees to offset rising temperatures, trap pollutants, and enhance environmental and human health and well-being. To maximize the benefits of planting trees and avoid further increasing social inequities, a city needs to prioritize where to establish trees by first identifying those areas of greatest need. This work aims to demonstrate a spatially explicit approach for cities to determine these priority locations to achieve the greatest returns on specific benefits. Criteria for prioritization were developed in tandem with the City of Joliette, Canada, and based on nine indicators: surface temperature, tree density, vegetation cover, resilience, tree size and age, presence of species at risk, land use type, socioeconomic deprivation, and potential for active transportation. The City’s preferences were taken into account when assigning different weights to each indicator. The resulting tree planting priority maps can be used to target street tree plantings to locations where trees are needed most. This approach can be readily applied to other cities as these criteria can be adjusted to accommodate specific tree canopy goals and planning constraints. As cities are looking to expand tree canopy, we hope this work will assist in sustaining and growing their urban forest, enabling it to be more resilient and to keep providing multiple and sustained benefits where they are needed the most.

Trees display contrasting specialized annual shoots during their life-span and along with ontogeny-driven modifications in their branching pattern, they can fulfill different combinations of light exploitation and space exploration functions Tree ontogeny is related to major changes in tree structure and function at different scales, from individual organs to the whole tree. Yet, little is known about the direct effects of tree ontogeny on shoot specialization and branching patterns. Such specific architectural changes occurring with tree growth and aging are of critical importance for understanding the response of trees to their environment. The uppermost branching system of 0.1- to 23-m-tall sugar maple trees was sampled at the end of the growing season. Measurements were made at both the branching system (n = 40) and annual shoot scales (n = 803). An algorithm for automated shoot typology was developed to characterize branching pattern variations. Sugar maple shoots were divided into four types with contrasting sizes and levels of foliage (i.e., relative biomass allocation into leaves, LMF). These morphological differences were interpreted as functional specializations for light exploitation (high LMF) or space exploration and support (low LMF). Only annual trunk shoots exhibited trait value changes during ontogeny such as a minimum allocation to foliage in the current-year shoots for the 5-m-tall trees, which is related to lower light interception capabilities but higher space exploration abilities. However, this relative loss of light interception function is compensated by ontogenetic changes at the branching system scale, which are associated with higher rates of ramification to produce lateral shoots. This study reveals how branching system and annual shoot traits change simultaneously during tree ontogeny to fulfill different functions, particularly light exploitation and space exploration.

In the present study, we screened 529 Brazilian individuals affected by inherited retinal disorders. A total of seven unrelated and nonsyndromic patients with RP1 biallelic variants (OMIM # 180100) were diagnosed in our centre and included in the study. They had classic retinitis pigmentosa with diagnosis at the first decade of life. The visual acuities were severely affected at a young age. The fundus aspects were similar among all patients. An atrophic ring was present around the fovea in several cases. All patients had molecular diagnosis, with six different RP1 variants. This study reports two new pathogenic variants - two frameshift duplications (c.1234dupA p.Met412Asnfs*7 and c.1265dupC p.Ala423Cysfs*2) and reinforces other four known pathogenic variants – two frameshift deletions (c.469delG p.Val157Trpfs*16 and c.3843delT p.Pro1282Leufs*12) and two stop gain mutations (c.1186 C > T p.Arg396* and c.1625C > G p.Ser542*). These findings broaden the spectrum of RP1 variants. This study also reviewed the fundus characteristics that clinically could raise the hypothesis of a retinitis pigmentosa due to RP1 gene. It is worthwhile to try to identify the disease-causing variants in each patient since it can provide prognostic information and be useful in genetic consultation and diagnosis in the future.

Urban forests are associated with important ecosystem services, such as reduced environmental exposure and improved human health. These benefits will become even more important with climate change, especially with most humans now living in cities. Yet urban trees are themselves threatened by the changing climate, unprecedented urban growth and new exotic pests and diseases. Hence, to maintain the services provided by urban forests, developing efficient tree management practices aimed at minimizing the risk of catastrophic tree mortality becomes ever more important. Traditional practices often promote low-diversity tree communities to meet the demands of a taxing urban environment and the preferences of citizens. However, these low-diversity communities are inherently more susceptible to collapse. Here we present an intuitively simple and user-friendly urban tree management approach that integrates the latest advances in functional ecology to minimize the risk of catastrophic urban tree mortality caused by future uncertain environmental conditions in order to maintain forest cover and preserve urban ecosystem services.

In a world facing rapid environmental changes, anticipating their impacts on biodiversity is of utmost relevance. Remotely-sensed Ecosystem Functional Attributes (EFAs) are promising predictors for Species Distribution Models (SDMs) by offering an early and integrative response of vegetation performance to environmental drivers. Species of high conservation concern would benefit the most from a better ability to anticipate changes in habitat suitability. Here we illustrate how yearly projections from SDMs based on EFAs could reveal short-term changes in potential habitat suitability, anticipating mid-term shifts predicted by climate-change-scenario models. We fitted two sets of SDMs for 41 plant species of conservation concern in the Iberian Peninsula: one calibrated with climate variables for baseline conditions and projected under two climate-change-scenarios (future conditions); and the other calibrated with EFAs for 2001 and projected annually from 2001 to 2013. Range shifts predicted by climate-based models for future conditions were compared to the 2001–2013 trends from EFAs-based models. Projections of EFAs-based models estimated changes (mostly contractions) in habitat suitability that anticipated, for the majority (up to 64%) of species, the mid-term shifts projected by traditional climate-change-scenario forecasting, and showed greater agreement with the business-as-usual scenario than with the sustainable-development one. This study shows how satellite-derived EFAs can be used as meaningful essential biodiversity variables in SDMs to provide early-warnings of range shifts and predictions of short-term fluctuations in suitable conditions for multiple species.

PURPOSE: Droughts are expected to become more intense and frequent. Mixed forests can be more resilient to extreme events, but are the individual trees in mixed forests also more resilient to drought? METHODS: We sampled 275 trees in 53 temperate forest stands in northern Belgium: monocultures, two-species mixtures, and the three-species mixture of Fagus sylvatica, Quercus robur, and Q. rubra. We related the annual basal area increment of individual trees to drought severity from 1955 to 2015 and calculated growth resistance, recovery, and resilience for six contrasting drought episodes (spring, summer, or full-year drought). RESULTS: Tree growth of the diffuse-porous F. sylvatica was more sensitive to drought, summer drought in particular. The ring-porous Q. robur and Q. rubra were mainly affected by spring drought. In general, a tree's growth response to drought was not affected by tree species diversity, but some identity effects emerged. CONCLUSION: The asynchrony in drought responses among the tree species (a large and immediate decrease in growth followed by swift recovery in F. sylvatica vs a smaller delayed response in Quercus) might stabilize productivity in forests in which both are present. The impact of the predicted increasing drought frequency will depend on the timing of the droughts (spring vs summer). ispartof: SCIENCE OF THE TOTAL ENVIRONMENT vol:650 issue:Pt 2 pages:3017-3026 ispartof: location:Netherlands status: published

Background: Worldwide, halting biodiversity loss is still a major challenge. Climate and land-use change (CLUC) are major drivers of species decline, and further expected to drive species’ future ranges. Understanding how these changes may impact species in the future is thus of utmost importance in the context of conservation and monitoring. This is especially critical for species of conservation concern, known to be more prone to extinction under environmental change. Aims: Here we addressed how CLUC may affect future distributions of 64 plant species designated under conservation legislation for Portugal and Spain. Current and future species distributions were modelled and projected under three CLUC scenarios. Range changes were analysed for each species and IUCN category, considering climate versus land-use change models, and the trade-offs between them. Results: Overall, our results depict consistent trends in the distribution of the targeted species under CLUC. The results also highlight potential extinction for some of the targeted species under climate change. However, under land-use change, 10 species are likely to expand their suitable habitat. Conclusions: Our research advances existing knowledge on how climate and land-use change may impact species of conservation concern in the Iberian Peninsula. Such knowledge is essential if further losses of species of conservation concern are to be proactively anticipated. Ultimately, such information can be useful to support data-driven conservation programmes and decision-making in the future.

In the past two decades, forest management has undergone major paradigm shifts that are challenging the current forest modelling architecture. New silvicultural systems, guidelines for natural disturbance emulation, a desire to enhance structural complexity, major advances in successional theory, and climate change have all highlighted the limitations of current empirical models in covering this range of conditions. Mechanistic models, which focus on modelling underlying ecological processes rather than specific forest conditions, have the potential to meet these new paradigm shifts in a consistent framework, thereby streamlining the planning process. Here we use the NEBIE (a silvicultural intervention scale that classifies management intensities as natural, extensive, basic, intensive, and elite) plot network, from across Ontario, Canada, to examine the applicability of a mechanistic model, ZELIG-CFS (a version of the ZELIG tree growth model developed by the Canadian Forest Service), to simulate yields and species compositions. As silvicultural intensity increased, overall yield generally increased. Species compositions met the desired outcomes when specific silvicultural treatments were implemented and otherwise generally moved from more shade-intolerant to more shade-tolerant species through time. Our results indicated that a mechanistic model can simulate complex stands across a range of forest types and silvicultural systems while accounting for climate change. Finally, we highlight the need to improve the modelling of regeneration processes in ZELIG-CFS to better represent regeneration dynamics in plantations. While fine-tuning is needed, mechanistic models present an option to incorporate adaptive complexity into modelling forest management outcomes.

Ongoing declines in biodiversity caused by global environmental changes call for adaptive conservation management, including the assessment of habitat suitability spatiotemporal dynamics potentially affecting species persistence. Remote sensing (RS) provides a wide-range of satellite-based environmental variables that can be fed into species distribution models (SDMs) to investigate species-environment relations and forecast responses to change. We address the spatiotemporal dynamics of species’ habitat suitability at the landscape level by combining multi-temporal RS data with SDMs for analysing inter-annual habitat suitability dynamics. We implemented this framework with a vulnerable plant species (Veronica micrantha), by combining SDMs with a time-series of RS-based metrics of vegetation functioning related to primary productivity, seasonality, phenology and actual evapotranspiration. Besides RS variables, predictors related to landscape structure, soils and wildfires were ranked and combined through multi-model inference (MMI). To assess recent dynamics, a habitat suitability time-series was generated through model hindcasting. MMI highlighted the strong predictive ability of RS variables related to primary productivity and water availability for explaining the test-species distribution, along with soil, wildfire regime and landscape composition. The habitat suitability time-series revealed the effects of short-term land cover changes and inter-annual variability in climatic conditions. Multi-temporal SDMs further improved predictions, benefiting from RS time-series. Overall, results emphasize the integration of landscape attributes related to function, composition and spatial configuration for improving the explanation of ecological patterns. Moreover, coupling SDMs with RS functional metrics may provide early-warnings of future environmental changes potentially impacting habitat suitability. Applications discussed include the improvement of biodiversity monitoring and conservation strategies.

Understanding the processes that underlie drought-related tree vitality loss is essential for anticipating future forest dynamics, and for developing management plans aiming at increasing the resilience of forests to climate change. Forest vitality has been continuously monitored in Europe since the acid rain alert in the 1980s, and the intensive monitoring plots of ICP Forests offer the opportunity to investigate the effects of air pollution and climate change on forest condition. By making use of over 100 long-term monitoring plots, where crown defoliation has been assessed extensively since 1990, we discovered a progressive shift from a negative to a positive effect of species richness on forest health. The observed tipping point in the balance of net interactions, from competition to facilitation, has never been reported from real ecosystems outside experimental conditions; and the strong temporal consistency of our observations with increasing drought stress emphasizes its climate change relevance. Furthermore, we show that higher species diversity has reduced the severity of defoliation in the long term. Our results confirm the greater resilience of diverse forests to future climate change-induced stress. More generally, they add to an accumulating body of evidence on the large potential of tree species mixtures to face manifold disturbances in a changing world. ispartof: GLOBAL CHANGE BIOLOGY vol:24 issue:9 pages:4304-4315 ispartof: location:England status: published

Climate change will impact forests and may impair their ability to provide essential ecosystem services in the decades to come. Addressing this challenge requires adjustments to forest management strategies as of now, but it is still unclear to what extent this is already in progress. Using data from surveys of 1131 forest owners and managers from seven European countries, we assessed how they perceive their role in adapting forest management to climate change. The surveys focused on foresters' observations of climate change impacts, the degree to which climate change is a part of their operational and strategic management, and their ability to address related risks and opportunities. We found evidence of a strong continent-wide climate change awareness among respondents, with 73% foresters convinced that climate change will impact their forest. However, only about one-third (36%) reported having modified their management practices, though figures vary widely between countries, from 14% in Portugal to 57% in Slovakia. Among the constraints limiting their actions, lack of knowledge and information emerged as a major barrier towards forest adaptation. Differences between countries could be linked to their socio-economic and political contexts. Our results further suggest that severely damaging events, such as windstorms, fires and pest outbreaks, present relevant opportunities to engage people with climate change and encourage action. Further work needs to be done in strengthening the relationship between scientific research and practice, working out context dependent measures to foster adaptation to changing climate and disturbance regimes in forest management.

Ensuring forest protection and the delivery of forest ecosystem services is a central aim of the European Union’s biodiversity strategy for 2020. Therefore, accurate modelling and mapping of ecosystem services as well as of biodiversity conservation value is an important asset in support of spatial planning and policy implementation. The objectives of this study were to analyse the provision of the multiple ecosystem services under two forestation scenarios (eucalyptus/pine vs. oak) at the watershed scale and to evaluate their possible trade-offs with the biodiversity conservation value. The Vez watershed, in northwest Portugal, was used as case study area, in which soil and water assessment tool (SWAT) was applied to simulate the provision of hydrological services, biomass and carbon storage services. Biodiversity conservation value was based on nature protection regimes and on expert judgement applied to a land cover map. Results indicated large provision of ecosystem services in the high and low mountain sub-basins. The overall performance for water quantity and timing is better under the shrubland and oak forest scenarios, when compared to the eucalyptus/pine forest scenario, which perform better for flood regulation and erosion control services, especially in the low mountain sub-basin. The current shrubland dominated cover also shows good performance for the control of soil erosion. The oak scenario is the one with less trade-offs between forest services and biodiversity conservation. Results highlight SWAT as an effective tool for modelling and mapping ecosystem services generated at the watershed scale, thereby contributing to improve the options for land management.

Earthworms have a significant influence on the structure, composition and functioning of forest ecosystems, but in spite of their role as ecosystem engineers, little is known on the factors controlling their distribution across European forests. Optimised sampling techniques, as well as more advanced statistical tools and geographical information systems have facilitated studies at the landscape scale. But these, and even larger-scale studies, are scarce due to data limitations, taxonomic inconsistencies and practical issues in linking existing databases. In this continental-scale field-based study we used boosted regression tree modelling to identify and evaluate the relative importance of environmental factors explaining earthworm incidence (presence/absence) and abundance (density and biomass) in European forests. To parameterise our models earthworms were sampled in six forest landscapes along a latitudinal gradient from the boreal north to the Mediterranean south in spring or autumn of 2012, together with several environmental variables. Earthworms were sampled using a combined method of mustard extraction and hand sorting of litter and a soil monolith, after which they were weighed and identified to functional group (epigeic, endogeic and anecic). We found that litter- and soil-related variables best explained earthworm incidence and biomass in European forests, leaving only a minor role to climate-related variables. Among the litter related variables, understory vegetation played an important role in explaining earthworm incidence and abundance. The relative importance of explanatory variables differed between models for incidence, density and biomass and between earthworm functional groups. Our results suggested that threshold values for soil C:N ratio, forest floor pH and understory plant biomass and plant nutrient concentrations have to be attained before earthworms can occur. Beyond these threshold values, variables like soil C:N ratio, tree litter C:P ratio and forest floor mass further explain earthworm biomass. Mechanisms behind these observations are discussed in the light of future earthworm distribution modelling at continental scale., This research has received funding from the European Union’s Seventh Programme (FP7/2007-2013) under grant agreement no. 265171

a b s t r a c t Species distribution models (SDMs) are increasingly used to understand rare and endangered species distributions, as well as the environmental pressures affecting them. Detailed knowledge of their distribution is critical for reporting its conservation status, and SDMs are potential tools to provide the relevant information to conservation practitioners. In this study, we modeled the distribution of Veronica micrantha, a vulnerable plant whose conservation status has to be periodically assessed under Article 17 of the Habitats Directive. The objective was to highlight the potential of SDMs for the assessment of threatened species within the periodical report on their conservation status. We used a spatially explicit modeling approach, which predicts species distributions by spatially combining two SDMs: one fitted with climate data alone and the other fitted solely with landscape variables. A comparison between the modeled distribution and the range obtained by classical methods (minimum convex polygon and Range Tool) is also presented. Our results show that while data-based approaches only consider the species known distribution, model-based methods allow a more complete evaluation of species distributions and their dynamics, as well as of the underlying pressures. This will ultimately improve the accuracy and usefulness of assessments in the context of EU reporting obligations. © 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).