Fiber-parenchyma trade-off underlies changes in tropical forest structure and xylem architecture across a soil water gradient

Wood anatomical traits can underpin tropical forest structural and functional changes across soil water gradients and therefore could improve our mechanistic understanding of how plants adapt to environmental change. We assessed how the variation in the forest maximum height (Hmax), stem diameter, and wood density (WD) is associated with variation in xylem traits (area of fibers and parenchyma, conductive area [CondA, sum of all vessels lumens], vessel lumen area [VLA], vessel density [VD], and vessel wall reinforcement [VWR]) across 42 plots of a Brazilian Atlantic Forest habitat that span strong soil water gradients. We found that in wetter communities, greater height and lower WD were associated with greater parenchyma area (capacitance), and lower fibers, VD, VWR. Contrastingly, in drier communities, lower height was associated with higher fiber area (xylem reinforcement), WD, VD, and VWR, while parenchyma area and vessels are reduced. Tree communities vary from conservative resource-use and structurally dependent hydraulic safety (Fibers) to acquisitive resource-use and capacitance dependent hydraulic safety (parenchyma). Such a fiber-parenchyma trade-off (FPT) underlies the variation in tree height across a soil water gradient. Wood anatomy is fundamental to understanding and predicting the impacts of environmental change on forest structure.

Ramdas layer and thermal wave during winter period

Earlier works on Ramdas Layer were about its certainty, its existence, energy balance on the layer and a matching mathematical model. We, first identified it in Thiruvananthapuram, Kerala, for eight days during a fortnight study on soil heat flux. A lifted minimum in temperature could have implications in agriculture and horticulture and so with a view to finding out a range of height through which Ramdas layer occurs, Ramdas-max, Ramdas-min are identified. On 24 January 1994, Ramdas layer occurred at a maximum height of 0.8m from the surface and the day is labeled as Ramdas-max. On 1 February 1994, it occurred at a lower height of 0.4m from the surface and the day is labeled as Ramdas-min. The thermal wave at the ground and at 0.05m depth, the range of thermal wave, its relationship with Ramdas layer, the temperature profile, the rate of change of heat in that layer with that at the surface and the subsoil heat flux at the sub-soil surface stratum(surface-0.05m) during R~mdas-max and Ramdas-min are duly compared and discussed.

The Spatiotemporal Evolution of the Diurnal Cycle in Two WRF Simulations of Tropical Cyclones

The properties of diurnal variability in tropical cyclones (TCs) and the mechanisms behind them remain an intriguing aspect of TC research. This study provides a comprehensive analysis of diurnal variability in two simulations of TCs to explore these mechanisms. One simulation is a well known Hurricane Nature Run, which is a realistic simulation of a TC produced using the Weather Research and Forecasting model (WRF). The other simulation is a realistic simulation produced using WRF of Hurricane Florence (2018) using hourly ERA5 reanalysis data as input. Empirical orthogonal functions and Fourier filtering are used to analyze diurnal variability in the TCs. In both simulations a diurnal squall forms at sunrise in the inner core and propagates radially outwards and intensifies until midday. At midday the upper-level outflow strengthens, surface inflow weakens, and the cirrus canopy reaches its maximum height and radial extent. At sunset and overnight, the surface inflow is stronger, and convection inside the RMW peaks. Therefore, two diurnal cycles of convection exist in the TCs with different phases of maxima: eyewall convection at sunset and at night, and rainband convection in the early morning. This study finds that the diurnal pulse in the cirrus canopy is not advectively-driven, nor can it be attributed to weaker inertial stability at night; rather, the results indicate direct solar heating as a mechanism for cirrus canopy lifting and enhanced daytime outflow. These results show a strong diurnal modulation of tropical cyclone structure, and are consistent with other recent observational and modeling studies of the TC diurnal cycle.

Habitation Sites Influence Tree Community Assemblages in the Great Bear Rainforest, British Columbia, Canada

Identifying how past human actions have influenced their environment is essential for understanding the ecological factors that structure contemporary ecosystems. Intertidal resource use by Indigenous Peoples for thousands of years has led to habitation sites containing vast shell midden deposits and facilitating long-term impacts on soil chemistry and drainage. Here we examine how these shell middens have impacted various forest metrics, such as species diversity, community composition, canopy height, and regeneration recruitment to determine if forests on habitation sites differ from the surrounding matrix. We surveyed known habitation sites with archeological evidence indicating past year-round human occupation, within the Hakai Lúxvbálís Conservancy on Calvert and Hecate Islands within the Great Bear Rainforest along British Columbia’s Central Coast. Our results demonstrate that habitation sites exhibit lower tree species richness, less relative species abundances, as such, displayed lower Shannon diversity and inverse Simpson values. The composition of tree communities on habitation sites was statistically different, with western hemlock and western redcedar densities increasing on non-habitation sites. Conversely, regeneration diversity at habitation sites was more even and exhibited elevated Shannon diversity and inverse Simpson values. The community composition of regeneration was more consistent among habitation and non-habitation sites; however, western redcedar, western hemlock and Sitka spruce were more abundant at habitation sites. For all tree species, maximum height was higher within the habitation sites; however, this trend was the most notable in western redcedar and Sitka spruce, which increased by an average of 4.8 m relative to non-habitation sites. Collectively, our findings suggest that long-term habitation alters forest community compositions. The landscape alterations within habitation sites promote conditions needed to support diverse, even, and abundant regeneration communities and consequently increase the height of the dominant coastal tree species. Thus, our results offer evidence that long-term influence by Indigenous communities have a persistent influence on coastal forests.

Performance of Tree Species on Waterlogged Sites of Canal Command Area: A Case Study of Bargi Dam, Jabalpur (Madhya Pradesh)

Bio-drainage is removal of excess soil water through bio-energy of fast-growing tree species having higher transpiration rate. Seven tree species viz. Albizia lebbek, Albizia procera, Acacia nilotica, Dalbergia sissoo, Eucalyptus tereticornis, FRI-4 and FRI-5 clones of Eucalyptus hybrid, Terminalia arjuna and Pongamia pinnata were evaluated for their performance through growth characteristics and biomass studies by planting on waterlogged sites on the bank of Left Bank Canal (LBC) of Bargi command area, Jabalpur district of Madhya Pradesh state (India). Eucalyptus hybrid, followed by Pongamia pinnata exhibited maximum height and biomass accumulation and its allocation to leaves and branches after four years of plantation,attributing the most desirable species for reclaiming waterlogged sites along canal command areas with similar edaphic and climatic conditions.

AVALIAÇÃO DAS CONSEQUÊNCIAS DO GALGAMENTO COSTEIRO DE 10/11 DE DEZEMBRO DE 2013 NA FRENTE URBANA DO CONCE-LHO DE SANTA CRUZ, ILHA DA MADEIRA

The expansion and consolidation of urban areas along the coast lead to the exposure of a large number of anthropic elements to sea storm events. It is with the aim of identifying and classifying the consequences of coastal overtopping that we analyse the recent storm surge of 10/11 December of 2013 which affected the urban coastal fringe of the city of Santa Cruz, on the south coast of Madeira Island. Therefore, the atmospheric conditions of wind intensity and atmospheric pressure are analysed and is characterised the direction of the waves and their maximum height, as well as the tide variation. After the oceanographic and meteorological characterization, it´s identified and evaluated the structural damage on the coastal zone and classified the functional consequences on the port structures affected by overtopping. The quantitative analysis of atmospheric and oceanographic data supports that this overtopping is a green water type resulting from an extratropical storm arising from the rapid reduction of atmospheric pressure and an average wind velocity of 30 km/h, affecting approximately 1600 meters of the coastal area of Santa Cruz. The qualitative analysis of the consequences shows that the port structures suffered severe to catastrophic consequences and dysfunction of their normal activities. The most affected areas are at the extremes of the urban front, registering reduced to insignificant consequences, in the intermediate area. Thus, it shows areas of greatest exposure, and areas that had presented seriously to severe damages, which can be highlighted in future episodes.

Herbicide performance in the control of Conyza spp. where three plant heights

Intensive use of the herbicide glyphosate has led to herbicide resistant Conyza spp. populations. Thus, there is a need to indicate alternative herbicides and the appropriate developmental stage for controlling these populations. This study identifies alternatives for controlling glyphosate-resistant horseweed, with treatment applications at different plant heights. For this purpose, field experiments were conducted in the 2016/17 and 2017/18 crop years. The evaluated treatments were: glyphosate (540 g ae ha-1), glyphosate (1080 g ae ha-1), glyphosate (2160 g ae ha-1), glyphosate (3240 g ae ha-1), glyphosate + 2.4-D (1080 + 1005 g ae ha-1), glyphosate + saflufenacil (1080 + 49 g ae/ai ha-1), paraquat (400 g ai ha-1), diquat (400 g ai ha-1), ammonium glufosinate (600 g ai ha-1), and control (without application). These treatments were applied to plants with a maximum of 5 cm; plants between 6 and 15 cm; and plants between 16 and 25 cm. The results showed that glyphosate did not control weeds, regardless of rate. With the exception of 2,4-D, which needs complementation with sequential application of another contact herbicide, all alternatives were viable for the control of Conyza spp. plants with a maximum height of 5 cm.

Quantitative Analysis of Performance Recovery in Semi-Professional Football Players after the COVID-19 Forced Rest Period

This study proposes the instrumental analysis of the physiological and biomechanical adaptation of football players to a fatigue protocol during the month immediately after the COVID-19 lockdown, to get insights into fitness recovery. Eight male semi-professional football players took part in the study and filled a questionnaire about their activity during the lockdown. At the resumption of activities, the mean heart rate and covered distances during fatiguing exercises, the normalized variations of mean and maximum exerted power in the Wingate test and the Bosco test outcomes (i.e., maximum height, mean exerted power, relative strength index, leg stiffness, contact time, and flight time) were measured for one month. Questionnaires confirmed a light-intensity self-administered physical activity. A significant effect of fatigue (Wilcoxon signed-rank test p < 0.05) on measured variables was confirmed for the four weeks. The analysis of the normalized variations of the aforementioned parameters allowed the distinguishing of two behaviors: downfall in the first two weeks, and recovery in the last two weeks. Instrumental results suggest a physiological and ballistic (i.e., Bosco test outcomes) recovery after four weeks. As concerns the explosive skills, the observational data are insufficient to show complete recovery.

Germinated Chickpea and Lupin as Promising Ingredients for Breadmaking—Rheological Features

Improving the alpha-amylase activity of wheat flour represents an opportunity to valorize wheat grains of low baking quality. In this sense, germinated legumes can be used to increase enzymatic activity, giving superior final product characteristics at the same time. The aim of this study was to underline the effects of chickpea (CGF) and lupin germinated flours (LGF) added simultaneously to white wheat flour on the rheological behavior of dough and to evaluate an optimal product microstructure. For this purpose, the falling number, dough rheological properties during mixing, 3D-deformation and fermentation, and the visco-elastic behavior were evaluated, the effects of factors (CGF and LGF levels) and their optimization have been studied by applying a full factorial design and response surface methodology (RSM). The LGF sample had a composition of 39.4% protein, 10.3% moisture, 6.9% fat, and 3.4% ash, whereas the CGF presented 21.1 % protein, 9.4% moisture, 5.2% fat, and 3.6% ash. The results showed that CGF and LGF determined the decrease of the falling number, dough water absorption, tolerance to kneading, dough consistency at 250 and 450 s, extensibility, the maximum height of the gas release curve, volume of gas retained by the dough at the end of the test, total volume of CO2 production, visco-elastic moduli, and gelatinization temperatures. On the other hand, dough elasticity and alveograph curve ratio increased proportionally to the increase of CGF and LGF addition levels. The optimal combination considering the rheological properties of dough was found to be 8.57% CGF, 5.31% LGF, and 86.12% wheat flour, with enhanced alpha-amylase activity being obtained compared to the control. These results provide valuable information on the possibility of using germinated legumes such as chickpeas and lupin in breadmaking to enhance wheat flour technological properties (besides traditionally used barley malt flour).

Winter frost damage and its link to early growth and survival in a poplar clone collection

The Northern European countries largely rely on poplars and their hybrids that are transferred northward from more southern regions, therefore, facing a trade-off between the use of full growth potential and sufficient tolerance of low temperatures. We characterized frost damage and its link to early growth and survival of 33 poplar genotypes at the age of one, three, and four years in a clonal collection on agricultural land. The survival after the first season varied from 42% to 99%. Half of the clones had autumn frost injuries with a maximum of 20% of trees damaged. The autumn frost-damaged trees were significantly (p < 0.001) higher before the injury than the undamaged trees with site mean 105.3 ± 7.9 and 72.0 ± 2.5 cm, respectively, but, at the clone mean level, the proportion of autumn frost-damaged trees had no link to survival (rho = 0.53, p < 0.001). The observed winter frost damage showed no relation (p < 0.05) regarding the proportion of trees with autumn frost damage. Trees with winter frost damage tended to be shorter than undamaged trees (p < 0.001) and had lower survival (rho = 0.47, p < 0.01). The maximum height difference of the clones among the studied years was in a magnitude from 2.4 to 2.9, and the stability of a clonal ranking increased with the age. The results emphasize the need for further monitoring of the clone performance under the local climatic conditions before recommendations of commercial use of particular clones in Latvia.