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Highlights • The drivers of the diversity of tropical wood-inhabiting fungi are unknown. • Resource explained alpha-diversity of tropical wood-inhabiting fungi. • Macroclimate explained beta-diversity of tropical wood-inhabiting fungi. • The drivers of the diversity of wood-inhabiting fungi are likely similar across ecosystems. • Dead wood of diverse tree species should be enriched across tropical macroclimates. Abstract Wood-inhabiting fungi are one of the most important groups of organisms as they contribute substantially to carbon and nutrient cycles by decomposing dead wood. Current knowledge of their occurrence, distribution, and drivers of their diversity derives almost exclusively from temperate and boreal forest ecosystems. We sampled wood-inhabiting fungi across Benin, a tropical country in West Africa with a strong north–south seasonality gradient consisting of three macroclimatic zones. We aimed at determining whether macroclimate or the resource (size or amount of dead wood, number of host tree species, and stage of wood decomposition) is more important for their diversity. Variation partitioning revealed a stronger partial effect of resource on fungal species richness and a strong effect of macroclimate on the community composition. A more detailed linear mixed-effects model revealed a significantly positive effect of host richness, amount of dead wood, and macroclimate on fungal species richness and a significantly positive effect of macroclimate and stage of wood decomposition on the community composition. These findings are consistent with patterns found in temperate and boreal ecosystems, which indicates the existence of general pattern of the diversity of wood-inhabiting fungi. Based on these results, we recommend that existing knowledge should be exploited for the conservation of wood-inhabiting fungi in tropical Africa. Thus, to protect tropical wood-inhabiting fungal diversity, we recommend that any size of dead-wood objects of diverse tree species be enriched in all tropical macroclimatic zones. [ABSTRACT FROM AUTHOR]

The current global warming scenario has led to a renewed interest in determining which species are more vulnerable to climate change. Hence, it is important to understand which factors can affect estimates of species vulnerability. We determined the critical thermal maxima (CT max ) for six species of North American anuran larvae and measured the environmental temperatures to which they are exposed during their aquatic stage to estimate their warming tolerance (WT; difference between the critical thermal maximum and the macro- and microhabitat maximum environmental temperatures). Our results indicate that these species exhibited CT max values (37.8–41.7 °C) that were similar to other temperate species and positively correlated only with environmental temperatures measured at the microclimate scale. This indicates that microclimatic variables are better predictors of CT max variation than macroclimate data. Moreover, most of the CT max variation found was associated with higher taxonomic levels, indicating that related species may show similar CT max values due to phylogenetic inertia. Studied species also exhibited high values of WT (10.3–22.6 °C), similar to temperate amphibian species from other bioregions. This indicates that there is a considerable gap between the species' critical thermal maximum and maximum environmental temperature, whether using datalogger (microclimate) or WorldClim (macroclimate) environmental data. However, WT estimates based on datalogger data were not related to those based on macroclimate environmental data. Finally, variation associated with the type of environmental data used (macro- vs. microclimate) had a profound influence on WT estimates. Hence, our perception of which species are more vulnerable to global warming changes may depend on the scale of the climate data used. [ABSTRACT FROM AUTHOR]

Establishment of vineyards is often forced towards geo-morphologically complex terroir where aspect, slope, relief and erosion are determining factors in orientation of rows. In this novel study, changes in primarily microclimate profiles and vine physiological behaviour with different row orientations were studied on a flat terrain in a semi-arid environment with the purpose of aiding vineyard management decisions and practices for production of grapes and wine. Effects of grapevine row orientation (NS, EW, NE-SW, NW-SE) of vertically trellised and shoot positioned Vitis vinifera L. Shiraz/101-14 Mgt on vineyard meso- and microclimate as well as vine physiological status, within the context of regional macroclimate, were investigated under field conditions over many seasons. Novel wind velocity and direction profiles in vineyard rows showed velocity in work rows paralleling ambient prevailing wind and direction flow patterns being affected by canopy development and row orientation; NW-SE and EW orientated rows maintained higher wind velocity in work rows than NS and NE-SW rows. Mesoclimatic photosynthetic active radiation was in line with macroclimate radiation. Microclimatically, EW orientated rows maintained lowest interior canopy light interception, NS orientation displayed highest values, peaking in morning and afternoon, whereas NE-SW and NW-SE orientations peaked primarily in afternoon and morning, respectively. The EW orientated rows captured largest portion of total radiation in the bunch zone from soil reflected radiation. Canopy interior temperature differences were likely masked by air temperature. Basal leaf water potential was relatively unaffected by row side; results point to internal regulation of whole plant water status. Leaf temperature showed minor differences. Relative humidity followed opposite trends to those of air- and leaf temperature. Leaves of EW orientated vines had highest average photosynthesis, corresponding to stomatal conductance and transpiration. Most uniform canopy photosynthesis occurred for NS and NW-SE orientations. Photosynthesis trends practically demonstrated mirror diurnal images for canopy sides of each orientation. Row orientation significantly affected meso- and microclimate, radiation in particular directly affecting energy/heat balances and concomitant canopy physiological processes. The study provided new insights into: vine physiological response to row orientation, the role of row orientation as viticulture practice; decision-making for establishment; and management of existing vineyards, irrespective of terroir soil and climatic conditions and product objectives. Results are globally relevant, especially within the context of climate change, and provide first comprehensive climatic/grapevine physiological evidence on the impact of grapevine row orientation as viticulture practice. [ABSTRACT FROM AUTHOR]

Abstract: Palaeoclimatic reconstructions from biological proxies, remains of organisms, suffer from sources of uncertainty that frequently are unacknowledged or even unrecognised. Primary amongst these is the need to identify, using available biological knowledge and understanding, the variables to which the organism(s) providing the proxy are sensitive, and hence that it is appropriate to reconstruct. These variables generally are not those conventionally recorded at meteorological stations, although they may be derived from these simply or using appropriate models. In the case of smaller organisms living close to the ground, in soil, or in aquatic environments, appropriate variables will relate to the microclimate. Reconstructing inappropriate variables introduces uncertainties and, especially under changed climatic conditions, is likely to give inaccurate results. A second important source of uncertainty arises when variables are reconstructed in isolation. In reality, most organisms respond concurrently to many variables, although two or three of these will usually predominate; these predominant variables also often have interacting effects. Isolating individual variables for reconstruction frequently will result in inaccurate reconstructions, the response to a second variable being aliased as an apparent change in the reconstructed variable. This can be overcome by concurrent reconstruction of the small number of variables that principally determine the distribution and abundance of the organism(s) from which the proxy is derived. Multi-proxy studies may give greater insight, but only when appropriate variables are reconstructed from each proxy. Further reductions in uncertainty, and new insights, are likely in future to be achieved by making concurrent reconstructions from two or more proxies, rather than, as at present, making separate reconstructions that may give incompatible results. The practice of making one-at-a-time reconstructions from individual samples along a core or profile often generates unrealistic sample-to-sample variability. Recent advances in the application of Bayesian modelling frameworks, however, offer concurrent reconstructions of two or more variables made concurrently for all samples in a sediment sequence. Recent improvements in the tools available to derive age-depth models open the possibility that in the near future it will be possible to make concurrent reconstructions from all samples from each of a series of sediment sequences. Knowledge of the physics of the climate system can then provide constraints on the spatial and temporal patterns in reconstructed values, further reducing their uncertainties. [Copyright &y& Elsevier]

Abstract: The paper investigates the possibility of assessing damage (health status) of silver fir (Abies alba Mill.) using multivariate regression models in the function of geomorphological, climatic and stand factors. Research was carried out in beech-fir forests (Abieti-Fagetum), on limestone-dolomite substrate, in the Dinaric part of the silver fir range in the Republic of Croatia. A general linear modelling method was used, where square terms and interaction terms (multiplication products) of original variables were treated as independent linear predictors. Twenty-seven separate models (all of them with significant part of explained fir damage variability) were developed regarding the different subsets of input data, different subsets of independent variables and different model design. Some of these models could be preliminary used for spatial predicting and mapping of fir damage in a frame of raster-GIS, for entire area of Dinaric part of Abieti-Fagetum in Croatia. [Copyright &y& Elsevier]

The model of spatial distribution of main forest soil groups in Croatia was developed as a function of basic pedogenetic factors: lithological substratum, macroclimate and relief. Used data about soil group, lithological substratum, terrain slope and aspect were collected on 1881 soil profiles. Macroclimatic data were estimated for each soil profile by spatial interpolation between meteorological stations. Feedforward neural networks were used as modelling tool. The final model has total classification correctness of 63.5% for training data set and 62.3% for independent test data set. The best result (86.4%) was achieved for fluvisols which are strongly spatially correlated with alluvial sediment in a flood plains. The worst result was achieved for luvisol (14.2%) which mainly comprised very old soils, probably developed under pedogenetic factors different from actual. The model was applied on entire Croatian territory aiming at construction of potential spatial distribution of main forest soils (without human impact), which was compared by the potential spatial distribution of major forest types modelled independently. [Copyright &y& Elsevier]

The effect of the macro- and microclimate on small mammal thermoregulation in the past has been studied independently instead of investigating the dual effect of both the components. This study addresses this dearth in knowledge by exploring the dual effect of both micro- and macro-climate on the thermoregulatory responses of two subterranean rodent species belonging to the family Bathyergidae, namely the more arid dwelling Mahali mole-rat (Cryptomys hottentotus mahali) and less arid dwelling Highveld mole-rat (C. h. pretoriae). Open flow through respirometry was used to quantify resting metabolic rates (RMR), evaporative water loss (EWL), core body temperature (T b), the ratio between the evaporative heat loss and metabolic heat production (EHL/MHP: evaporative cooling capacity) and conductance (C dry) over a range of increasing ambient temperatures (T a ; 20–42 °C). Furthermore, RMR, EWL, T b, EHL/MHP and C dry were measured at the mole-rat's thermal maxima (43 °C). At cooler temperatures, the arid-dwelling C. h. mahali possesses a broader thermoneutral zone (~5 °C; 27.2–32.1 °C), while C. h. pretoriae possess a single thermoneutral point (33.6 °C). This is in response to the greater selection pressure to conserve energy in the more arid regions inhabited by C. h. mahali. Contrastingly, at hotter temperatures, there were no significant thermoregulatory differences in EWL, EHL/MHP or C dry responses between the two sub-species, as expected due to the limitations bestowed by the buffered microclimates (burrow systems). Thus, neither macro-climate, nor micro-climate singularly moulds the thermoregulatory adaptations, but rather, it appears to be a combined effect from both climates. Other small endotherms may share this dual response, and therefore, it is crucial to incorporate the effect of both macro- and microclimates into future climate models when determining the ecological capabilities and persistence of a species. • This is a novel study assessing the effect of macro and micro-climate on subterranean rodents' thermal biology. • The 2 mole-rat sub-species possess similar heat tolerances and dissipation efficiency. • The 2 mole-rat sub-species possess different breadths of thermoneutral zones. • Both macro and micro-climate moulds the thermoregulatory adaptations of these mole-rat sub-species. [ABSTRACT FROM AUTHOR]