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Made available in DSpace on 2021-06-25T10:22:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 The objective of this study was to evaluate the changes that occurred during processing white breads enriched with 5, 7.5, and 10% of medium-polymerized inulin (MPI). Farinographic analysis revealed that enrichment caused the development time and dough stability to increase by up to 69.9% and 62.8%, respectively, when 7.5% of MPI was incorporated into wheat flour. This indicated that the added MPI strengthened the doughs. Conversely, alveographic analysis demonstrated that MPI was harmful to the gluten network. The specific volume and humidity of breads with up to 7.5% MPI were similar to those of the control (MPI-free) bread. During bread storage for 10 days, we noticed that the retrogradation rate increased only for the bread sample with 10% MPI. However, MPI enrichment, regardless of concentration, promoted an increase in the Avrami exponent and affected bread firmness. Bread staling analysis indicated that the moisture difference between crumb and crust was higher for the MPI-enriched breads than for the control. Moreover, we prepared more consistent doughs and fresh breads with MPI contents of up to 7.5%, which presented good quality and were good fiber sources; however, we determined that inulin did not present an anti-staling effect. Department of Food Engineering and Technology UNESP—São Paulo State University IFAC—Federal Institute of Acre Department of Food Engineering and Technology UNESP—São Paulo State University

A moisture-heat transfer and stress model of corn kernels based on multi-component heterogeneity was developed and verified to predict the stress cracking during hot-air drying. Simulated results showed that the moisture gradient and von Mises stress of each corn component simulated by the verified model increased first and then decreased, where the von Mises stress in the outer layer of corn kernels was larger than that in the inner layer. The maximum von Mises stress of each corn component increased with the increase of drying temperature and the decrease of relative humidity. The stress cracks were mainly formed in hard endosperm and soft endosperm, because the maximum von Mises stress of hard endosperm was larger than the yield stress of the two components, which were agreement with statistical results of stress cracks. Therefore, a drying operation with lower temperature and higher relative humidity is beneficial for inhibiting the stress cracking in corn kernels.

Climate in high latitude environments is predicted to undergo a pronounced warming and increase in precipitation, which may influence the terrestrial moisture gradients that affect vegetation distribution. Vegetation cover can influence rates of greenhouse gas production through differences in microbial communities, plant carbon uptake potential, and root transport of gases out of the soil into the atmosphere. To predict future changes in greenhouse gas production from High Arctic ecosystems in response to climate change, it is important to understand the interaction between trace gas fluxes and vegetation cover. During the growing seasons of 2008 and 2009, we used dark static chambers to measure CH4 and N2O fluxes and CO2 emissions at Cape Bounty, Melville Island, NU, across a soil moisture gradient, as reflected by their vegetation cover. In both years, wet sedge had the highest rates of emission for all trace gases, followed by the mesic tundra ecosystem. CH4 consumption was highest in the polar semi-desert, correlating positively with temperature and negatively with moisture. Our findings demonstrate that net CH4 uptake may be largely underestimated across the Arctic due to sampling bias towards wetlands. Overall, greenhouse gas flux responses vary depending on different environmental drivers, and the role of vegetation cover needs to be considered in predicting the trajectory of greenhouse gas uptake and release in response to a changing climate.

The system for analyzing the hydrotropic curvature with a moisture gradient in wild-type Arabidopsis roots was modified. Optimal conditions were determined for detecting a hydrotropic curvature of 90° just after 4 h of stimulation. This system only requires 15 ml of a solution of K2CO3 with a density of 1.48 g·ml-1 to generate a rapid moisture gradient inside a square Petri dish without decreasing root growth. In this, the root growth rate observed in hydrostimulated wild-type and miz1 mutant, utilized as a negative control, increases sixfold compared with those roots examined using the former method.

In wood processing, wood is exposed to an environmental temperature of less than 0 °C for some time, which mainly occurs during the air drying of wood in the winter months, or when lumber is stored in wood piles outdoors before the kiln drying process. In these cases, the wood freezing process increases the degree of freezing of the wood, subsequently significantly affecting the process of its heating during further processing (for example, in the cutting process). The most common method is heating by humid air, during the hot air drying of wood. We analyzed the temperature profiles on a cross-section of wood and moisture losses due to the freezing process and the size of moisture gradients. We compared theoretical calculations of the time required for defrosting and heating of wood with the experimentally measured values. The results show that the moisture content (MC) of wood has a remarkable effect on the wood freezing process. In samples with an average MC of 35.47%, the temperature drop was faster. After 10 h, the temperatures on the entire cross-section of the samples reached the lowest value of −13.2 °C. In samples with an average initial MC of 81.38%, three stages of temperature reduction in the wood were observed. The temperature dropped and the lowest temperature of −20.11 °C was reached after 24 h. The defrosting and heating process of samples with lower MC was significantly easier. The desired temperature of 65 °C in the middle of the samples was reached in 2 h and 20 min. The total time to defrost and heat the second group of samples (MC > FSP) was 3 h 30 min.

International audience; Behavioral thermoregulation is an efficient mechanism to buffer the physiological effects of climate change. Thermal ecology studies have traditionally tested how thermal constraints shape thermoregulatory behaviors without accounting for the potential major effects of landscape structure and water availability. Thus, we lack a general understanding of the multifactorial determinants of thermoregulatory behaviors in natural populations. In this study, we quantified the relative contribution of elevation, thermal gradient, moisture gradient, and landscape structure in explaining geographic variation in thermoregulation strategies of a terrestrial ectotherm species. We measured field-active body temperature, thermal preferences, and operative environmental temperatures to calculate thermoregulation indices, including thermal quality of the habitat and thermoregulation efficiency for a very large sample of common lizards (Zootoca vivipara) from 21 populations over 3 yr across the Massif Central mountain range in France. We used an information-theoretic approach to compare eight a priori thermo-hydroregulation hypotheses predicting how behavioral thermoregulation should respond to environmental conditions. Environmental characteristics exerted little influence on thermal preference with the exception that females from habitats with permanent access to water had lower thermal preferences. Field body temperatures and accuracy of thermoregulation were best predicted by the interaction between air temperature and a moisture index. In mesic environments, field body temperature and thermoregulation accuracy increased with air temperature, but they decreased in drier habitats. Thermoregulation efficiency (difference between thermoregulation inaccuracy and the thermal quality of the habitat) was maximized in cooler and more humid environments and was mostly influenced by the thermal quality of the habitat. Our study highlights complex patterns of variation in thermoregulation strategies, which are mostly explained by the interaction between temperature and water availability, independent of the elevation gradient or thermal heterogeneity. Although changes in landscape structure were expected to be the main driver of extinction rate of temperate zone ectotherms with ongoing global change, we conclude that changes in water availability coupled with rising temperatures might have a drastic impact on the population dynamics of some ectotherm species.

With widespread influence on global climate and weather extremes, the Madden-Julian Oscillation (MJO) plays a crucial role in subseasonal prediction. Our latest global climate models (GCMs), however, have great difficulty in realistically simulating the MJO. This model inability is largely due to problems in representation of MJO’s cumulus organization. This study, based on a series of idealized aqua-planet model experiments using an atmospheric-only GCM, clearly demonstrates that MJO propagation is strongly modulated by the large-scale background state in which the lower-tropospheric mean moisture gradient and zonal winds are critical. Therefore, when tuning climate models to achieve improved MJO simulations, particular attention needs to be placed on the model large-scale mean state that is also significantly affected by cumulus parameterizations. This study indicates that model biases in representing MJO propagation may be related to the widely reported double-ITCZ (intertropical convergence zone) problem in climate models.

Identifying the drought-tolerance traits of plant species originating from a moisture gradient will increase our understanding of the differences and similarities in plant drought tolerance. However, which traits can be used to evaluate drought tolerance remain an open question. Here, we conducted a common-garden experiment on 37 shrub species originating from desert to humid regions. The correlations between plant traits and the native environmental conditions were studied. Leaf sizes and Huber values were significantly correlated with most climate variables of the shrubs’ origins. The osmotic potentials at full turgor (π100), turgor loss point (ΨTLP), and midday leaf water potential (Ψmid) were significantly correlated with most climate variables of their origins. We proposed using leaf sizes, Huber values, and ΨTLP as predictors of drought tolerance across shrub species and shrub biomes. Statistically significant correlations were found between π100, ΨTLP, and specific leaf area (SLA). However, owing to the weak correlations between SLA and the climate variables of the shrubs origins and between Huber values and leaf size and turgor loss traits, it was difficult to integrate leaf morphological traits with physiological traits to find a simple way to accurately quantify drought-tolerance-related differences among these shrub species.

Plants colonize post-mining areas such as spoil heaps even without human interference, by spontaneous succession. Knowledge of this process, its direction and role in shaping the vegetation is desirable not only from an ecological point of view but also in the application of remediation techniques of such environmental burdens. The aim of our study was to analyse plant species composition and to describe a succession pattern at two mineralogically different spoil heaps near the city of Banska Bystrica (central Slovakia). Hierarchical cluster analysis was used in PC-ORD software to classify physiognomic vegetation types (PVT) at heaps and synoptic tables were generated in Juice software according to species percentage of frequency and their median cover. At the Hg-heap Veľka studňa we recorded a total of 335 taxa of vascular plants and 83 taxa of bryophytes within 21 identified PVT, which were grouped into 4 clusters (forest, wetland, grassland and ruderal cluster). A total of 111 taxa of vascular plants and 76 taxa of bryophytes were recorded at the Cu-heap Podlipa and here 9 PVT formed 3 clusters (initial, non-forest and forest cluster). At both heaps PVT, represented as individual successional stages, formed a distinct continuum along the moisture gradient (in dry and wet areas). We can consider both heaps as species-rich with different diagnostic and constant species and a development of various microhabitats. In addition, bryophytes greatly contribute to species composition and richness and their assamblages in initial stages of succession can be important towards the higher ones.

Arabidopsis roots sense the moisture gradient in soils and grow toward an area with higher water potential – a process called hydrotropism. Our previous study has shown that the apoplastic proton extrusion in root tips is influenced by brassinosteroids (BRs) receptor BR-INSENSITIVE1 (BRI1) and is crucial for hydrotropic response in Arabidopsis. Here we show that BRI1 interacts directly not only with Arabidopsis plasma membrane H+-ATPase 2 (AHA2) but also with Arabidopsis plasma membrane H+-ATPase 7 (AHA7). Therefore, BRI1 may affect hydrotropic response via regulating the activities of AHA2 and AHA7.

Diversification of Amazon birds led by climate stability: lineages originated in the wetter west and dispersed into the drier east., The Amazon is the primary source of Neotropical diversity and a nexus for discussions on processes that drive biotic diversification. Biogeographers have focused on the roles of rivers and Pleistocene climate change in explaining high rates of speciation. We combine phylogeographic and niche-based paleodistributional projections for 23 upland terra firme forest bird lineages from across the Amazon to derive a new model of regional biological diversification. We found that climate-driven refugial dynamics interact with dynamic riverine barriers to produce a dominant pattern: Older lineages in the wetter western and northern parts of the Amazon gave rise to lineages in the drier southern and eastern parts. This climate/drainage basin evolution interaction links landscape dynamics with biotic diversification and explains the east-west diversity gradients across the Amazon.

Rapid/moderate/slow pressure reduction modes of vacuum cooling (VC) with pressure reduction rates ranging from 0.0043 to 0.0502 s-1 were developed. The effects of VC in different modes on the cooling efficiency and quality-related attributes of different edible parts of pakchoi including total and free water contents, colour differences, respiration rates, membrane stability and microstructures were investigated, and the cluster analysis (CA) was employed for visualizing and classifying the VC-induced quality variation. Results showed that the leaf and the petiole exhibited different temperature changes and vacuum tolerances, of which the adaxial epidermis of the leaf was more sensitive to VC, showing more severe cell damage due to the internal moisture gradient. The rapid pressure reduction mode (α1 = 0.0502 s-1) could predominately improve cooling efficiency and minimize the quality attenuation, while the moderate pressure reduction mode (α2 = 0.0184 s-1) contributed to better temperature uniformity and colour acceptance. Moreover, the result of CA further confirmed the above conclusions, suggesting that α1 and α2 endowed pakchoi with similar quality-related attributes to the fresh one. The current study proved that the slow pressure reduction mode should be avoided for uses in VC of leafy vegetables.

This study examined the changes in the properties of beech wood (Fagus sylvatica L.) after intense drying. Beech wood with false red heartwood was selected as the test specimen. The test samples had dimensions of 50 mm thickness, 180 mm width, and 350 mm length. The specimens were divided into two groups, false red heartwood and sapwood. These specimens were selected with different angles of the growth rings (radial and tangential). The results showed that samples with red heartwood, in comparison to samples with sapwood content, had a remarkable effect in covering. Observation of specimens with false red heartwood and sapwood before and after drying process revealed significant differences in color changes and measured values during the covering-slicing test, but not between samples with different growth ring angles.

A northeast- to southwest-oriented surface dryline with a dew point gradient of 1 °C per 10 km develops along the eastern Indian coast during the entire premonsoon season. Deep, hot, dry air of up to 500 hPa moves from arid regions in Southwest Asia and Western India to the Bay of Bengal (BoB), and warm, shallow, moist air from the BoB penetrates below the dry air, forming an inclined moisture gradient aloft to the east and reaching the surface to the west. The slope of the gradient depends on the vertically increased southwesterly wind over the BoB, which gradually intensifies from March to May. Diurnal low-level temperature variations over the land cause periodic movements of the dry-moist air convergence zone at the surface in the zonal direction. During the premonsoon, the average east–west diurnal oscillation of the surface dryline is approximately 100 km, and the eastward movement is almost three times faster than the westward movement.

Trees at upper treelines are exposed to more extreme environmental conditions than those at lower elevations. Climate changes at the upper treeline facilitate the establishment or intensify the mortality of trees and, consequently, affect species distributions. The structure and density of individuals of Nothofagus pumilio above the upper treeline, together with their temporal patterns of establishment, were determined in three sites located along a west-east precipitation gradient across the Patagonian Andes. Patterns of tree establishment were compared to regional variations in temperature and precipitation, as well as to indexes of atmospheric circulation that modulate northern Patagonian climate. Mesic and dry sites along the moisture gradient have a lower density of newly established trees; however, individuals show larger basal diameters and greater annual growth rates, heights, and number of branches than those established in humid sites. In wet areas, the high density of individuals reflects the higher rates of N. pumilio establishment and survival. At drier treelines, low snow persistence, associated with longer growing seasons, appears to be related to the larger size of individuals. At all sites, patterns of tree establishment are characterized by an abrupt increase in recruitment starting in the mid-1970s and a marked decrease in the late 1990s. The onset of tree establishment above the treeline coincides with an increase in regional spring-summer temperature in the year 1977, concurrent with the negative-to-positive shift in the phase of the Pacific Decadal Oscillation (PDO). In contrast, the decrease in N. pumilio establishment since the late 1990s coincides with an opposite shift (positive to negative) in the PDO. This recent change in the PDO phase did not significantly modify the mean values but increased the interannual variability of the spring-summer temperatures in the region. Changes in the PDO, which encompasses complex variations in environmental conditions at the upper treeline, are more closely related to N. pumilio establishment than are variations in temperature or precipitation alone. In addition, the distinction between the effects of changes in mean values versus the effects of climate variability is crucial for properly predicting forest responses to climate changes. Fil: Srur, Ana Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Villalba, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Rodriguez Catón, Milagros Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina Fil: Amoroso, Mariano Martin. Universidad Nacional de Rio Negro. Sede Andina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Marcotti, Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina

Drought is a key factor affecting forest ecosystem processes at different spatio-temporal scales. For accurately modeling tree functioning – and thus for producing reliable simulations of forest dynamics – the consideration of the variability in the timing and extent of drought effects on tree growth is essential, particularly in strongly seasonal climates such as in the Mediterranean area. Yet, most dynamic vegetation models (DVMs) do not include this intra-annual variability of drought effects on tree growth. We present a novel approach for linking tree-ring data to drought simulations in DVMs. A modified forward model of tree-ring width (VS-Lite) was used to estimate seasonal- and site-specific growth responses to drought of Scots pine (Pinus sylvestris L.), which were subsequently implemented in the DVM ForClim. Ring-width data from sixteen sites along a moisture gradient from Central Spain to the Swiss Alps, including the dry inner Alpine valleys, were used to calibrate the forward ring-width model, and inventory data from managed Scots pine stands were used to evaluate ForClim performance. The modified VS-Lite accurately estimated the year-to-year variability in ring-width indices and produced realistic intra-annual growth responses to soil drought, showing a stronger relationship between growth and drought in spring than in the other seasons and thus capturing the strategy of Scots pine to cope with drought. The ForClim version including seasonal variability in growth responses to drought showed improved predictions of stand basal area and stem number, indicating the need to consider intra-annual differences in climate–growth relationships in DVMs when simulating forest dynamics. Forward modeling of ring-width growth may be a powerful tool to calibrate growth functions in DVMs that aim to simulate forest properties in across multiple environments at large spatial scales.

Drying time reduction has always been a major concern in the drying process and is achievable by increasing the temperature of the surrounding air. To optimize the quality of the resulting material, drying conditions must be enhanced to reach a balanced correlation between the drying time and quality of the dried timber. This paper analyses the high-temperature drying of wood and the optimization of this process, as well as the effect that drying temperature and thickness of beech timber specimens has on the drying process. The high-temperature drying of beech wood was carried out by means of hot air in a laboratory drier for maximum 33 hours at maximum temperatures of 130 and 150 °C. The initial moisture content of samples was approximately 70%. The resulting drying times were short in comparison to conventional warm-air drying, which is caused by the high intensity of drying during the removal of bound water. Finally, it can be concluded that the thickness of the dried specimens is a significant factor in the process of high-temperature drying of beech wood.

We describe a new pollen and Sea Surface Temperature (SST) record with sub-centennial to centennial resolution from a well-dated sediment core (D13882) obtained from the Atlantic margin of the southwest Iberian Peninsula. The core provides new insights into the dynamics of five ecological pollen-based groups (temperate forests, Mediterranean forests, pinewoods, heathlands and steppe) since the Late Pleistocene (last 13,260 cal yr BP). The record shows that the Early Holocene was marked by an increase of temperate and Mediterranean taxa, accompanied by a reduction of steppic plants, reflecting warm and relatively moist conditions when compared with the previous Younger Dryas episode. The timing of this Temperate and Mediterranean Forest (TMF) maximum which reflects optimum conditions of temperature and precipitation is regionally specific, as detected through a comparison of three marine cores across the Iberian Peninsula. Maximum TMF development occurs between 9760 and 7360 cal yr BP in D13882 whereas at a site to the northwest (MD03-2697), the maximum occurs some centuries earlier, and at a southeast site (MD95-2043), the maximum is evident later. The duration of the forest maximum is also progressively longer from northwest to southwest to southeast. A transition from forested ecosystems to heathland over western Iberia characterises the Middle Holocene, starting from around 7360 cal yr BP in D13882, suggesting reduced seasonality and a more Atlantic climate character with more moisture evenly available through the year. This contrasts with the aridity recorded in southeast Iberian sites and reflects a stable precipitation gradient between the wetter west and drier east of the Iberian Peninsula. Against this backdrop, pinewoods had a continuous presence, albeit with a trend of steady decline through the Holocene. The time-transgressive pattern in the TMF maximum is best explained by a less favourable moisture balance in the drier southeast sector, which was particularly important during the Early Holocene. Despite the relatively short duration of the Holocene interglacial (one half precession cycle), our observations support a key role for orbital forcing in the temporal expression of major vegetation groups, specifically the decline in summer insolation and the precession-related passage of perihelion season from summer to winter.

Mapping heathland habitats is generally challenging due to fine-scale habitats as well as spectral ambiguities between different classes. A multi-seasonal time-series of multispectral RapidEye data from several phenological stages was analysed towards the classification of different vegetation communities. A 3-level hierarchical dependent classification using Import Vector Machines was tested, based on the assumption that a probabilistic output per class would help the mapping. The first level of the hierarchical classification was related to the moisture gradient, which was derived from Ellenberg’s moisture indicative value. The second level aimed to separate plant alliances; the third level differentiated individual plant associations. For the final integration of the three classification levels, two approaches were implemented: (i) the F1-score and (ii) the maximum classification probability. The overall classification accuracies of both methods were found to be similar, around 0.7. Nevertheless, based on our expert knowledge we found the probabilistic approach to provide a more realistic picture and to be more practical compared to the result using the F1-score from the management point of view. In addition, the overall performance of the maximum probabilistic approach is better in the sense that the same accuracy of 0.7 was achieved with a differentiation of 33 classes instead of only 13 classes for the F1-score, meaning that the method is able to separate more spectral classes at a more detailed level providing the same accuracy.

Studies of termite mound building have considered the mud they prepare, its properties and its composition. Here we consider the behaviors of the mound building termites Macrotermes michaelseni, (Sjostedt), in the presence of the viscous boundary layer (VBL), which spontaneously forms over any surface that air passes over. We looked how soil moisture and air vapor are coupled to form a feedback loop and a spatiotemporal precursor to worker termites in the presence of mound material. We explored residency and activities of workers when presented with a VBL and either varying substrate temperature gradients or a soil moisture transition within the soil substrate. We report the emergence of a ‘vapor conveyor’, which forms around a neutral evaporative equilibrium point (NEEP) at the soil/air interface, where the soil-borne moisture temperature (along the gradient) and the 100% saturated air-borne vapor temperature coincide within the VBL, forming a bubble of neutral mass transfer which, we propose, worker termites are sensitive to as viscosity changes within. We found, on average, that 67% (std. dev 27%) of behavioral events (clustering, excavation, and deposition) occurred within 1 °C either side of the NEEP. We found negative correlation (− 0.78) between the substrate temperature gradient (0.1–0.9 °C mm −1 ) and the extents of behavioral activity, suggesting coupling between soil-borne moisture and air-borne vapor advection within the VBL. We recorded unique behaviors relating to interaction with the viscosity of vapor-saturated air at this scale. We speculate that workers may exploit the VBL to overcome a classic trade-off, i.e., how to push activities forward into potentially desiccating environments while conserving moisture in both the termites and the soil they build with.

Given the habitat moisture (air humidity or soil moisture) preferences of many forest bryophytes, we explored whether the depth-to-water (DTW) index, derived from remotely sensed Light Detection and Ranging (LiDAR) data, was related to fine-scale patterns of spatial variation in bryophyte abundance, diversity, and composition. The goal was to assess the utility of the topographic DTW index as a tool to decipher trends in bryophyte assemblages along a site wetness gradient in the boreal mixedwood forest. Discrete Airborne Laser Scanning (ALS) data were acquired over the entire Ecosystem Management Emulating Natural Disturbance (EMEND) experimental site located in northwestern Alberta, Canada (56° 46′ 13″ N, 118° 22′ 28″ W), based on which we calculated a mathematical index of approximate depth to water at or below the soil surface at 1 m resolution using the Wet-Areas Mapping model. Bryophytes (mosses and liverworts) were sampled in permanent sample plots in unmanaged forest stands of varying dominant canopy tree composition. The relationships between DTW and bryophyte cover, richness, diversity, and composition in broadleaf (deciduous)-, mixed, and conifer-dominated boreal forest stands were analyzed using linear mixed-effect models and multivariate analyses. Bryophyte cover was highest in conifer-dominated forest, which occupied the wetter end of the DTW gradient, followed by mixed forest, whereas broadleaf forest, which occupied the drier end of the DTW gradient, had the lowest cover but highest bryophyte diversity. Bryophyte cover in conifer-dominated forests was positively related to site moisture (negatively related to the DTW index). In contrast, bryophyte species richness and diversity were negatively related to site moisture (increased at higher DTW values) in all forest types. DTW explained significant variation in bryophyte species composition in mixed forests, while indicator species analysis identified species with preferences for wet, moist, and dry site conditions in each forest type. Our results corroborate the importance of site moisture as a driver of bryophyte assemblages but, interestingly, there were important differences among forest types, which themselves are distributed across a gradient of site moisture. Our study demonstrates the utility of the topographic DTW index for understanding fine-scale (plot-level) variation in bryophyte assemblages in forested landscapes.

This study explored the relative roles of climate and phylogenetic background in driving morphometric trait variation in 10 spruce taxa in China. The study further addressed the hypothesis that these variations are consistent with species turnover on climatic gradients. Nine morphometric traits of leaves, seed cones, and seeds for the 10 studied spruce taxa were measured at 504 sites. These data were analyzed in combination with species DNA sequences from NCBI GenBank. We detected the effects of phylogeny and climate through trait‐variation‐based K statistics and phylogenetic eigenvector regression (PVR) analyses. Multivariate analyses were performed to detect trait variation along climatic gradients with species replacement. The estimated K‐values for the nine studied morphometric traits ranged from 0.19 to 0.68, and the studied environmental variables explained 39–83% of the total trait variation. Trait variation tended to be determined largely by a temperature gradient varying from wet‐cool climates to dry‐warm summers and, additionally, by a moisture gradient. As the climate became wetter and cooler, spruce species tended to be replaced by other spruces with smaller needle leaves and seeds but larger cones and seed scales. A regression analysis showed that spruce species tended to be successively replaced by other species, along the gradient, although the trends observed within species were not necessarily consistent with the overall trend. The climatically driven replacement of the spruces in question could be well indicated by the between‐species variation in morphometric traits that carry lower phylogenetic signal. Between‐species variation in these traits is driven primarily by climatic factors. These species demonstrate a narrower ecological amplitude in temperature but wider ranges on the moisture gradient.

The aim of the study was to present effects of soil properties, especially moisture, on the quantity and quality of soil organic matter. The investigation was performed in the Czarna Rózga Reserve in Central Poland. Forty circular test areas were located in a regular grid of points (100 × 300 m). Each plot was represented by one soil profile located at the plot’s center. Sample plots were located in the area with Gleysols, Cambisols and Podzols with the water table from 0 to 100 cm. In each soil sample, particle size, total carbon and nitrogen content, acidity, base cations content and fractions of soil organic matter were determined. The organic carbon stock (SOCs) was calculated based on its total content at particular genetic soil horizons. A Carbon Distribution Index (CDI) was calculated from the ratio of the carbon accumulation in organic horizons and the amount of organic carbon accumulation in the mineral horizons, up to 60 cm. In the soils under study, in the temperate zone, moisture is an important factor in the accumulation of organic carbon in the soil. The highest accumulation of carbon was observed in soils of swampy variant, while the lowest was in the soils of moist variant. Large accumulation of C in the soils with water table 80–100 cm results from the thick organic horizons that are characterized by lower organic matter decomposition and higher acidity. The proportion of carbon accumulation in the organic horizons to the total accumulation in the mineral horizons expresses the distribution of carbon accumulated in the soil profile, and is a measure of quality of the organic matter accumulated. Studies have confirmed the importance of moisture content in the formation of the fractional organic matter. With greater soil moisture, the ratio of humic to fulvic acids (HA/FA) decreases, which may suggest an increase in carbon mobility in soils.

[EN] Hydrotropism is a genuine response of roots to a moisture gradient to avoid drought. An experimental system for the induction of hydrotropic root response in petri dishes was designed by pioneering groups in the fi eld. This system uses split agar plates containing an osmolyte only in a region of the plate in order to generate a water potential gradient. Arabidopsis seedlings are placed on the MS agar plate so that their root tips are near the junction between plain MS medium and the region supplemented with the osmolyte. This elicits a hydrotropic response in Arabidopsis roots that can be measured as the root curvature angle.

Understanding how forested ecosystems respond to climatic changes is a challenging problem as forest self-organization occurs simultaneously across multiple scales. Here, we explore the hypothesis that soil water availability shapes above-ground competition and gap dynamics, and ultimately alters the dominance of shade tolerant and intolerant species along the moisture gradient. We adapt a spatially explicit individual-based model with simultaneous crown and root competitions. Simulations show that the transition from xeric to mesic soils is accompanied by an increase in shade-tolerant species similar to the patterns documented in the North American forests. This transition is accompanied by a change from water to sunlight competitions, and happens at three successive stages: (i) mostly water-limited parkland, (ii) simultaneously water- and sunlight-limited closed canopy forests featuring a very sparse understory, and (iii) mostly sunlight-limited forests with a populated understory. This pattern is caused by contrasting successional dynamics that favour either shade-tolerant or shade-intolerant species, depending on soil moisture and understory density. This work demonstrates that forest patterns along environmental gradients can emerge from spatial competition without physiological trade-offs between shade and growth tolerance. Mechanistic understanding of population processes involved in the forest–parkland–desert transition will improve our ability to explain species distributions and predict forest responses to climatic changes.

Moisture-responsive materials are gaining greater interest for their potentially wide applications and the readily access to moisture. In this study, we show the fabrication of moisture-responsive, self-standing films using sustainable cellulose as starting material. Cellulose was modified by stearoyl moieties at first, leading to cellulose stearoyl esters (CSEs) with diverse degrees of substitution (DSs). The films of CSE with a low DS of 0.3 (CSE0.3) exhibited moisture-responsive properties, while CSEs with higher DSs of 1.3 or 3 (CSE1.3 and CSE3) not. The CSE0.3 films could reversibly fold and unfold as rhythmical bending motions within a local moisture gradient due to the ab- and desorption of water molecules at the film surface. By spray-coating CSE3 nanoparticles (NPs) onto CSE0.3 films, moisture-responsive films with non-wetting surface were obtained, which can perform quick reversible bending movements and continuous shape transition on water. Furthermore, bilayer films containing one layer of CSE0.3 at one side and one layer of CSE3 at the other side exhibited combined responsiveness to moisture and temperature. By varying the thickness of CSE0.3 films, the minimal bending extent can be adjusted due to altered mechanical resistances, which allows a bending movement preferentially beginning with the thinner side.

The published literature reviews various factors responsible for rice breakage during milling. Artificial drying immediately after harvesting is one of the main causes of kernel fissures in temperate countries like France. These virtually invisible fissures lead to high breakage ratios during milling. The present work attempts to construct a simulation tool capable of predicting head rice yield during drying, so that the design of industrial rice dryers can be improved. Relationships were established between head rice yield and both moisture content gradient and kernel temperature. The influence of the temperature and evaporating capacity of the drying air on head rice yield after processing was studied. Experimental quality data were fitted to a kinetic model. Evaporating capacity was identified as the principal factor responsible for head rice yield reduction: head rice yield is not affected by high drying temperatures if evaporating capacity remains low. The kinetic model developed by the authors describes head rice yield accurately, with an error of 6%.

International audience; In the context of the European Space Agency's (ESA) Soil Moisture and Ocean Salinity (SMOS) mission, we present a study of the emission and of the bistatic scattering coefficient of rough surfaces at 1.4 GHz and the effects of moisture and temperature gradients. A new approach for the calculation of rough surface scattering and emission at L-band has recently been. This approach relies on the use of ANSYS's numerical computation software HFSS (High Frequency Structure Simulator), which in turn solves Maxwell's equations using the Finite Element Method (FEM). The interest of this approach is that it can be extended to calculate the emission and scattering of complicated multilayer media, including features such as volume effects, gradients effects and inclusions, as well as rough surfaces. At L band, volume effects in the upper layer of soil should be taken into account. In particular, moisture or thermal phenomena lead to the presence of gradients. In this paper we present the work we have done to use FEM method to compute thermal effects and water infiltration effects in ground. Coupling electromagnetic and thermal computation we are able to study scattering of media such as permafrost or effects of rapid changes in temperature condition. We can also study the effect of moisture gradients or the impact of rainfall events on bistatic scattering coefficient or emissivity of soil. It can also be very useful for global observations with a frequent repeat coverage (future NASA Soil Moisture Active/Passive mission SMAP). In the present study we present the effects of water infiltration in ground (as moisture gradients) on the emissivity and bi-static scattering coefficient of soil.

Red false heartwood is a defect that largely influences the quality of beech wood and is formed by air penetration into mature wood. The air in the mature zone accelerates the process of parenchyma dying and initiates the formation of red false heartwood substances and tyloses. For this study, the selections of suitable logs were made immediately after logging the trees on the same day. The first log was chosen without any type of red false heartwood, and the second log was chosen with healthy red false heartwood. The drying schedule was divided into two phases. After these measurements it was concluded that red false heartwood had a remarkably lower initial moisture content (MC) than the mature wood. The measured difference was almost 20%. The moisture gradient before drying was higher in the red false heartwood samples than in the mature wood samples. The red false heartwood had no effect on the intensity of casehardening. For both groups of samples, the drying quality was good without damaging the dried samples.

Cellular slime molds were isolated from 75% of soil samples from 50 prairie remnants in southern Wisconsin. Total populations (cells per g of soil) were greatest in wet sites, intermediate in wet-mesic and mesic sites, and least in dry-mesic sites. Populations were slightly higher in dry than in dry-mesic sites, possibly because soils in dry sites had higher water-retaining capacities than soils in dry-mesic sites. Dominant species included Polysphondylium violaceum in wet prairies, Dictyostelium giganteum and P. violaceum in mesic prairies, and P. pallidum and D. sphaerocephalum in dry prairies. Dictyostelium sp. (YS) and P. pallidum both had greater populations at the two extremes of the moisture gradient than in mesic sites. Other species isolated included D. discoideum, D. lacteum, D. mucoroides, D. polycephalum, D. purpureum and D. rosarium. Average species diversity ranged from 3.2 species per site in dry-mesic prairies to 4.6 per site in wet-mesic prairies.