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The panel approach with fixed effects and nonlinear weather effects has become a popular method to uncover weather impacts on economic outcomes, but its ability to capture long‐run climatic adaptation remains unclear. Building upon a framework proposed by McIntosh and Schlenker (2006), this paper identifies empirical conditions under which the nonlinear panel approach can approximate a long‐run response to climate. When these conditions fail, the obtained relationship may still be interpretable as a weighted average of underlying short‐run and long‐run responses. We use this decomposition to revisit recently published climate impact estimates. For spatially large panels, the estimated temperature–outcome relationship mostly reflects the long‐run climatic response; this is not so for precipitation. We find some evidence of long‐run climatic adaptation for crop yield outcomes in the United States and France. [ABSTRACT FROM AUTHOR]

Copyright of Plants, People, Planet is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: Bird and tree species distributions will shift along with future climatic conditions through direct effects related to species responses to bioclimatic variables. In addition, tree species composition changes should indirectly drive changes in forest bird habitats. Here, we predicted the effects of climate changes on the amount of reachable habitat for forest birds and teased apart the role of the indirect effects. Location: France. Methods: We projected tree and bird species distributions (2020 and 2050) using generalized additive models which accounted for climatic conditions at a large scale (France) and local environmental conditions at regional scale. The projections combined two scenarios of climate changes (RCP 2.6 and 8.5) and two scenarios of forest management (increase in either deciduous or coniferous stands). We modelled the amount of reachable habitat with landscape graphs and the equivalent connectivity index (EC) for five birds associated to the main forest types of the study area. To differentiate the sources of EC change between 2020 and 2050, we compared two future landscape graphs including only the indirect effect, or the direct and indirect effects of climate changes. Results: For birds with low and intermediate thermal maxima, climate‐based distributions were nearly stable over time (absence of direct effects), EC change was only attributed to indirect effects. In contrast, for bird species with high thermal maximum, EC change was mostly driven by direct effects (more favourable climatic conditions) and little by indirect effects. Main conclusions: Using an innovative modelling framework that bind species distribution and connectivity models with climate and land use changes in forest, we showed that EC dynamics could be completely due to climate‐driven changes in tree species composition. Our results highlight the importance of accounting for the indirect effects of climate changes, especially in forests where major shifts in tree species composition are expected. [ABSTRACT FROM AUTHOR]

Under the influence of climate change, wildfire regimes are expected to intensify and expand to new areas, increasing threats to natural and socioeconomic assets. We explore the environmental and economic implications for the forest sector of climate‐induced changes in wildfire regimes. To retain genericity while considering local determinants, we focus on the regional level and take Mediterranean France as an example. Coupling a bioeconomic forest sector model and a model of wildfire activity, we perform spatially explicit simulations under various levels of radiative forcing. By using a probabilistic framework, we also assess the propagation of several sources of uncertainty to the forest sector, considering both climate‐induced uncertainty and the intrinsic stochasticity of the fire process. By the end of the century, summer burned areas increase by up to 55%, causing moderate losses of merchantable timber and forest carbon stocks, with cascading impacts for industrial activities and climate mitigation in the forest sector. Implications for industries remain limited, but we observe price increases, especially for softwoods, as well as spatially differentiated changes in producer welfare. Inter‐annual fluctuations explain most of uncertainty in wildfire activity, but their impacts on the forest sector are quickly dampened. Over time, owing to the cumulative nature of wildfire impacts on forest resources, uncertainty related to climate warming, climate models' response and stochasticity intrinsic to the wildfire phenomenon strongly increase in relative importance. Results reassert the need to consider multiple futures in prospective assessments, including uncertainty inherent to natural processes, often omitted in large‐scale economic assessments. Plain Language Summary: Forest fires in the Mediterranean are expected to become more numerous, more intense, and to reach new areas due to climate change. Forest resources, carbon sequestrated in forests, as well as economic activities related to forestry, are threatened by this evolution. This article focuses on Southern France and uses large‐scale model simulations to explore these dynamics. We show that burned areas in forests may increase by more than half by 2100, leading to a decrease in forest resources (timber) by up to 5%. Besides, prices for wood products may increase, especially for softwoods, with implications for the welfare of timber producers and consumers. Moreover, these results are heterogenous across space, and areas to the south and to the west are more gravely affected. However, these trends come with relatively large uncertainties. We show that uncertainties concerning the evolution of forest fires themselves are largely due to annual variability in weather conditions. On the contrary, uncertainties concerning economic activity in forestry are mostly due to the unknown future evolution of greenhouse gas emissions and to differences in climate models functioning. Our results reassert the need to consider several possible sources of uncertainty in long‐term prospective assessments. Key Points: Models project an intensification of wildfire regimes in southern France, losses of forest resources and carbon, disturbances to forestryUncertainty in projections is dominated by annual fluctuations for wildfire activity, by choice of climate model/scenario for forestryProspective bioeconomic assessments need to consider multiple possible futures but also stochasticity intrinsic to disturbance processes [ABSTRACT FROM AUTHOR]

Seedling recruitment is a bottleneck for population dynamics and range shift. The vital rates linked to recruitment by seed are impacted by amplified drought induced by climate change. In the Mediterranean region, autumn and winter seedling emergence and mortality may have strong impact on the overall seedling recruitment. However, studies focusing on the temporal dynamic of recruitment during these seasons are rare. This study was performed in a deciduous Mediterranean oak forest located in southern France and quantifies the impact of amplified drought conditions on autumn and winter seedling emergence and seedling mortality rates of two herbaceous plant species with meso-Mediterranean and supra-Mediterranean distribution (respectively, Silene italica and Silene nutans). Seedlings were followed from October 2019 to May 2020 in both undisturbed and disturbed plots where the litter and the aboveground biomass have been removed to create open microsites. Amplified drought conditions reduced seedling emergence and increased seedling mortality for both Silene species but these negative effects were dependent on soil disturbance conditions. Emergence of S. italica decreased only in undisturbed plots (-7%) whereas emergence of S. nutans decreased only in disturbed plots (-10%) under amplified drought conditions. The seedling mortality rate of S. italica was 51% higher under amplified drought conditions in undisturbed plots while that of S. nutans was 38% higher in disturbed plots. Aridification due to lower precipitation in the Mediterranean region will negatively impact the seedling recruitment of these two Silene species. Climate change effects on early vital rates may likely have major negative impacts on the overall population dynamic. [ABSTRACT FROM AUTHOR]

Copyright of Functional Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Premise: Worldwide, ecosystems are threatened by global changes, including biological invasions. Invasive species arriving in novel environments experience new climatic conditions that can affect their successful establishment. Determining the response of functional traits and fitness components of invasive populations from contrasting environments can provide a useful framework to assess species responses to climate change and the variability of these responses among source populations. Much research on macrophytes has focused on establishment from clonal fragments; however, colonization from sexual propagules has rarely been studied. Our objective was to compare trait responses of plants generated from sexual propagules sourced from three climatic regions but grown under common environmental conditions, using L. peploides subsp. montevidensis as a model taxon. Methods: We grew seedlings to reproductive stage in experimental mesocosms under a mediterranean California (MCA) climate from seeds collected in oceanic France (OFR), mediterranean France (MFR), and MCA. Results: Seed source region was a major factor influencing differences among invasive plants recruiting from sexual propagules of L. peploides subsp. montevidensis. Trait responses of young individual recruits from MCA and OFR, sourced from geographically distant and climatically distinct source regions, were the most different. The MCA individuals accumulated more biomass, flowered earlier, and had higher leaf N concentrations than the OFR plants. Those from MFR had intermediate profiles. Conclusions: By showing that the closer a seedling is from its parental climate, the better it performs, this study provides new insights to the understanding of colonization of invasive plant species and informs its management under novel and changing environmental conditions. [ABSTRACT FROM AUTHOR]

Groundwater recharge depends generally on precipitation. In this study, a geographical information system (GIS) procedure was applied to assess the climate change effect on groundwater recharge in the Grand Est region of France. The analysis comprises high‐resolution climate models that reflect the long‐term climatological regime. The hydrological properties include aquifers, land‐cover and terrain morphology data, which were used to develop the potential infiltration map of the study area. Two parameters, the De Martonne aridity index and effective precipitation, were combined into a 5 × 5 matrix to assess the climate change effect on groundwater recharge during the past (1990s), present (2020s) and future (2050s) periods. The present and future intense aridization and the depletion of the effective precipitation (< 650 mm) reveal the negative effects of climate change on aquifers' recharge in the Grand Est region. The areas with high and very high climate effects will increase in the 2020s and 2050s. These areas extend mainly in the western, north‐central and northeastern parts of the region occupying the Rhine, Aube and Marne valleys. The medium effect could be found in the central, southern and northwestern parts, while the low impact on groundwater recharge was verified in the northwestern and southeastern parts of the region. The area with low effects of climate change extends mostly in the Vosges and Ardennes mountains. These findings contribute to the long‐term hydrogeological studies in the Grand Est region. [ABSTRACT FROM AUTHOR]

Abstract: Under the concept of the ‘Blue Pacific’, island nations are placing increased priority on the oceans, seeking to integrate policy on climate change, maritime security, fisheries and ocean biodiversity. This agenda however affects France, one of the remaining colonial powers in the Pacific, which controls a vast maritime domain in the region. The 2016 decision to incorporate the French dependencies New Caledonia and French Polynesia as full members of the Pacific Islands Forum raises a series of diplomatic challenges for Forum island countries. This article outlines France's interest in the Blue Pacific, in areas such as exclusive economic zones, security, research, climate and maritime boundaries. It then details problems facing Forum member countries arising from France's ongoing control of its three dependencies in the region, including uncertainty over legal standing in the Forum; the capacity to sign treaties; policy making on security in the Forum; policy issues on fisheries and climate in other member agencies of the Council of Regional Organisations of the Pacific; relations with other Forum dialogue partners; resource exploitation by the colonial power; and disputes over maritime boundaries. [ABSTRACT FROM AUTHOR]

Aim We investigated whether climate change has affected the potential feeding activity of a winter active larva, the pine processionary moth (PPM), Thaumetopoea pityocampa L., and whether it may explain its range expansion. Location The study area is France and, at a smaller scale, the Paris Basin. Methods We used a statistical model derived from Huchon and Démolin [1970 Revue Forestière Française (special issue: La lutte biologique en forêt), 220–234] to test whether their model, updated with climate change, could explain the observed range expansion. Since Battisti and colleagues have recently shown that climate could affect survival of the PPM through its effect on feeding activity, we also developed a mechanistic model based on larval feeding requirements (night air temperature above 0 °C and temperature inside the nest above 9 °C on the preceding day). We reconstructed the geographical distribution of feeding activity and we compared the resulting change with the PPM range expansion. Results The statistical model did not successfully predict the observed expansion but the mechanistic model showed considerable change in the feeding activity of the PPM. In the Paris Basin, the PPM border coincided with a zone unfavourable for feeding activity in the period 1992–96. Feeding conditions became more favourable in the period 2001–04, and the PPM succeeded in crossing this zone. Over larger temporal and spatial scales improved feeding conditions in the north-western part of France were forecast by the mechanistic model. Main conclusions (1) The range distribution of the PPM in the Paris Basin is no longer limited by unfavourable feeding conditions. (2) The pattern of range expansion of the PPM is now governed mainly by its dispersal capabilities and host tree distribution. (3) At the country scale, this approach gives an approximate prediction of the potential distribution of the PPM, though the model may not be reliable in mountainous regions. [ABSTRACT FROM AUTHOR]

summary: Northern populations of Phragmites australis (Cav.) Trin. ex Steud. (common reed) often flower so late that the ability to produce viable seeds before winter dieback can be limited. If climate changes as predicted, the reed may become able to set seed further north in its range. This would have implications for the ability of reed to colonize new sites as well as for the distribution of animals which eat reed seeds in winter. A survey of 34 British populations in 1993 and 1994 showed that seed production is highly variable between sites, ranging from 0 to 100%. Southern and western populations tended to show the highest seed sets, although some southern populations were infertile and some northern sites set seed. Average seed weight tended to be higher in sites which showed good seed set. Seeds from sites with high average seed weight tended to germinate more readily. The seed‐setting capability of populations was successfully associated with climatic conditions at the time of flowering. However, seed weight was not found to relate to climate, but depended on seed production and overall plant height. Logistic regression modelling indicated that the best seed sets should occur in P. australis when: (i) August rainfall is low; (ii) the combined rainfalls of September and October are high; and (iii) the combined temperatures of these months are high. The model accounts for approximately one third of the variation in observed seed sets between sites, indicating that other, unmeasured, factors might also play a part in determining seed set in P. australis. At three northern populations which were studied in more detail, a number of genotypes coexisted, and legitimate pollen germination and pollen‐tube growth was observed in each case. As no seed set occurred in two of these, self‐incompatibility cannot explain poor seed setting. [ABSTRACT FROM AUTHOR]