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Wood growth is key to understanding the feedback of forest ecosystems to the ongoing climate warming. An increase in spatial synchrony (i.e., coincident changes in distant populations) of spring phenology is one of the most prominent climate responses of forest trees. However, whether temperature variability contributes to an increase in the spatial synchrony of spring phenology and its underlying mechanisms remains largely unknown. Here, we analyzed an extensive dataset of xylem phenology observations of 20 conifer species from 75 sites over the Northern Hemisphere. Along the gradient of increase in temperature variability in the 75 sites, we observed a convergence in the onset of cell enlargement roughly toward the 5th of June, with a convergence in the onset of cell wall thickening toward the summer solstice. The increase in rainfall since the 5th of June is favorable for cell division and expansion, and as the most hours of sunlight are received around the summer solstice, it allows the optimization of carbon assimilation for cell wall thickening. Hence, the convergences can be considered as the result of matching xylem phenological activities to favorable conditions in regions with high temperature variability. Yet, forest trees relying on such consistent seasonal cues for xylem growth could constrain their ability to respond to climate warming, with consequences for the potential growing season length and, ultimately, forest productivity and survival in the future.

Abstract This paper presents a mathematical model of coupled heat and mass transfer in multi-layers of loose adsorbent grains under realistic conditions of adsorption heat transformation (AHT) cycle. The model allows a simulation of the adsorption dynamics in the adsorbent layer which consists of a low number of loose adsorbent grains (1 ≤ n ≤ 4). Firstly, the model was validated by comparison with the kinetics of isothermal water adsorption on a single spherical grain, initiated by a small pressure drop, for which an analytical solution is well-known. Afterwards, the model was applied to simulate non-isothermal water dynamics for adsorbent-heat exchanger configurations of one, two and four layers of loose grains of Fuji silica type RD. The grains are located on a metal support subjected to a fast variation of temperature as it takes place during isobaric phases of AHT cycle. The system of partial differential equations was solved by using the COMSOL Multiphysics® simulation environment. The calculated sorption dynamics is in a good accordance with the experimental data obtained for n = 1, 2 and 4 under the same boundary conditions. Moreover, the model was used to simulate the ad/desorption process for different grain sizes (0.45, 0.85 and 1.7 mm). The input parameters which ensure the best data fitting were compared with those experimentally determined for Fuji silica type RD as well as with the input data of other heat and mass transfer models presented in the literature. The developed model gives a powerful tool for accurate simulation of dynamic features for the AHT units with practically interesting configuration of the adsorber/heat exchanger which utilizes a low number of loose adsorbent grains. Moreover, useful information about radial and axial distributions of the temperature and vapour concentration can be obtained for both gas and solid phases. Finally, the specific cooling power of AHT cycle was estimated and recommendations on the cycle dynamic optimization were made.

Abstract Climate change is among the key anthropogenic factors affecting species’ distribution, with important consequences for conservation. However, little is known concerning the consequences of distributional changes on community‐level interactions, and responses by generalist species might have many ecological implications in terms of novel interactions with resident species. In this study, we applied Ecological Niche Models and niche analysis to three generalist bat species, Hypsugo savii, Pipistrellus kuhlii, and Pipistrellus pipistrellus, which share similar ecological traits and are sympatric in parts of their ranges. Our aims were to investigate how predicted climate change will affect species’ distribution and to analyse the degree of climatic niche overlap between the three species, in both the current and the future scenarios (2050 and 2070; Representative Concentration Pathways 4.5 and 8.5). Temperatures were the most important predictors influencing species’ range expansion in future. According to our models, Pipistrellus kuhlii and Hypsugo savii may expand their geographic ranges towards northern latitudes, whereas the geographic range of the less thermophilous Pipistrellus will shift northwards, resulting in it losing the southern portion in Europe. The already considerable degree of climatic niche overlap between the three species will increase further in future. On the basis of our findings, within the new areas potentially colonised by all three species in future, alterations in community‐level balance might occur, bringing about effects that are only partially predictable. In view of this, we highlight the need for further research and improved monitoring of bat communities in areas that are predicted to be particularly vulnerable to climate change.

Recently, a new composite "LiCl inside Multi-Wall Carbon NanoTubes" (LiCl/MWCNT) has been suggested as water sorbent for Adsorption Thermal Energy Storage (ATES), because it has a large thermal storage capacity of 1.7 kJ/g for a daily heat storage cycle. This work addresses the results of the study of water sorption dynamics on the novel composite loaded into representative small scale fragments of a common finned flat-tube HEx. The study consists of four parts: (1) shaping the LiCl/MWCNT composite as grains using polyvinyl alcohol (PVA) as a binder; (2) analysis of sorption equilibrium for the pair "LiCl/ MWCNT/PVA - water"; (3) measuring the thermal storage capacity of the granulated LiCl/ MWCNT/PVA composite; (4) investigation of water sorption dynamics on the LiCl/MWCNT/PVA under typical conditions of the daily storage cycle. It is shown that the thermal storage capacity of the LiCl/MWCNT/PVA composite equals 1.5-1.6 kJ/g. The specific power reaches 4.2 and 9.8 kW/kg of the heat release and thermal storage stages, respectively. The results obtained show that the working pair "LiCl/MWCNT/PVA - water" appears to be advantageous for ATES.

Abstract The aim of the present paper is the experimental characterization of adsorbent materials suitable for practical applications in adsorption refrigeration systems, employing ethanol as refrigerant. Different commercial activated carbons as well as a properly synthesized porous composite, composed of LiBr inside a silica gel host matrix, have been tested. A complete thermo-physical characterization, comprising nitrogen physi-sorption, specific heat and thermo-gravimetric equilibrium curves of ethanol adsorption over the sorbents, has been carried out. The equilibrium data have been fitted by means of the Dubinin – Astakhov equation. On the basis of the experimental data, a thermodynamic evaluation of the achievable performance of each adsorbent pair has been estimated by calculating the maximum COP (Coefficient of Performance) under typical working boundary conditions for refrigeration and air conditioning applications. The innovative composite material shows the highest thermodynamic performances of 0.64–0.72 for both tested working conditions. Nevertheless, the best carbonaceous material reaches COP value comparable with the synthesized composite. The results have demonstrated the potential of the chosen adsorbents for utilization in adsorption cooling systems.

Farming of shellfish and seaweeds is a tested tool for mitigating eutrophication consequences in coastal environments, however as many other marine economic activities it should be a subject of marine spatial planning for designating suitable sites. The present study proposes site selection framework for provisional zebra mussel farming in a eutrophic lagoon ecosystem, aimed primarily at remediation purposes. GIS-based multi-criteria approach was applied, combining data from empirical maps, numerical models and remote sensing to estimate suitability parameters. Site selection and prioritisation of suitable areas considered 15 environmental and socio-economic criteria, which contributed to 4 optimisation models (settlement, growth and survival of mussels, environmental and socio-economic) and 3 predefined scenarios representing provisional goals of mussel cultivation: spat production, biomass production and bioremediation. The relative importance of each criterion was assessed utilizing the Analytical Hierarchy Process. Site suitability index was calculated and the final result of the site selection analysis was summarized for 3 scenarios and overall suitability map. Four suitability classes (unsuitable, least, moderately and most suitable) were applied, and 3 most suitable zones for provisional zebra mussel cultivation with 12 candidate sites were selected accordingly. The integrated approach presented in this study can be adjusted for designating zebra mussel farming sites in other estuarine lagoon ecosystems, or cultivation of other mussel species for bioremediation purposes. The analytical framework and the workflow designed in this study are also adoptable for addressing other aquaculture-related spatial planning issues.