Significant Effect Of Temperature Research Articles

Hydrogen and Oxygen Isotopic Characteristics and Influencing Factors of "Three Waters" in Shandian River Basin

In this study, we collected precipitation from February 2020 to February 2022 and the surface water and groundwater in the wet (August) and dry (October) periods of 2021 in the Shandian River Basin. Stable isotope technology was used to analyze the temporal and spatial changes in the hydrogen and oxygen stable isotopes of the "three waters" in the basin to explore the relationship between water isomorphs and environmental factors and to reveal the water conversion relationship using the end element mixing model. The results showed that the slope and intercept of the local precipitation line were smaller than the local atmospheric precipitation line. The water vapor mainly came from westerly water vapor, polar air mass, and East Asian monsoon circulation. The precipitation isotope had a significant temperature effect. In terms of time, the isotopes of surface water and groundwater were more enriched in the dry season than those in the wet season, and the d-excess values of surface water and groundwater were lower than the global average, indicating strong local evaporation. Spatially, the δ18O value of the rivers had the same change characteristics in the wet and dry seasons, showing gradual enrichment from the upstream to the downstream, and the groundwater δ18O high value area was unevenly distributed in space, with groundwater δ18O values becoming more depleted with the increase in burial depth. The highest slope of the groundwater water line was 7.87 in the wet season, which was very close to the slope of the local atmospheric precipitation line and river water line, indicating that there was a complex hydraulic connection between the "three waters" in the wet season. The surface water in the study area was mainly supplied by precipitation during the wet season and then by groundwater runoff. These results can provide a theoretical basis for revealing the hydrological cycle in arid and semi-arid areas.

Effects of Temperature and Air Pollution on Emergency Ambulance Dispatches: A Time Series Analysis in a Medium-Sized City in Germany

Abstract Management of adverse health-related effects from heat waves requires comprehensive and accessible sources of information. This paper examines the effects of temperature and air pollution on human health and identifies areas with increased occurrence of emergency ambulance dispatches in the city of Würzburg, Bavaria, Germany, and discusses the applicability for health care interventions and urban planning. An overdispersed Poisson generalized additive model was used to examine and predict the association and potential lag of exposure between temperature, air pollution, and three types of emergency ambulance dispatches during the study period from 2011 to 2019. A linear model was used to estimate heat-wave effects. A line density function was used to identify areas with increased occurrence of dispatches. Significant effects of temperature were detected for nontraumatic and cardiovascular diseases after exceeding a threshold temperature. The exposure–response relationships showed an increased relative risk up to two days after exposure for nontraumatic and cardiovascular diseases. Results indicate a significant association between presence of heat waves and cardiovascular diseases with up to 17% (95% confidence interval: 5.9%–30.0%) increased relative risk on a heat-wave day relative to a non-heat-wave day. Dispatches for cardiovascular diseases occur more often in areas with a high population and building density, especially in summer. The analyses identified hotspots of heat-related dispatches in areas with increased population and building density and provides baseline information for interventions in future urban planning and public health care management based on data commonly available even in small cities. Significance Statement The purpose of this study is to demonstrate how authorities in even medium- and small-sized cities can assess health impacts of heat stress or air pollution using free accessible emergency ambulance data and software to incorporate the outcomes in their spatial planning or health care management. This is important as ongoing climate change requires all urban communities to adapt and reduce adverse impacts of climate change and air pollution. Our results show that extreme heat leads to increased emergency ambulance dispatches in a medium-sized city in Germany and provide a spatial overview of where health care interventions and urban planning can focus to mitigate adverse effects.

The impact of high temperatures on bird responses to alarm calls

Given the current pace of climate change, high temperature events will become increasingly frequent in many parts of the world. Predicting how high temperatures will impact the behavior of songbirds—highly sensitive to temperature change due to their tendency to be small in size, and to have high metabolic rates and diurnal habits—is therefore crucial and urgent. However, the behavioral impacts of high temperatures on acoustic communication in birds have rarely been studied. Responsiveness to antipredator signals is an important behavior to consider because failure to detect such signals could be lethal. We investigated whether, in great tits (Parus major), high temperatures would affect behavioral responses to playback of conspecific mobbing calls. We found a significant lag effect of temperature on how closely great tits would approach the playback speaker, with birds approaching less closely at higher temperatures. Further, we found that the emission of mobbing calls by great tits was affected by the current ambient temperature, with birds calling less at higher temperatures. The results suggest that at high temperatures, great tits change their tactic from active defense to less active response. High temperatures can thus induce behavioral shifts in great tits. In the current context of increasing average temperatures, such effect of temperature on response to vital indicators such as antipredator signals could impact survival when inducing greater risk of depredation.Significance statementClimate change is causing heatwaves to increase in number and intensity. High temperatures can reduce the ability of birds to respond to vocalizations. Here, we test if high temperatures affect the ability of great tits (Parus major) to respond to conspecific mobbing calls—these calls generally serve to mob a predator and to recruit conspecifics and heterospecifics to join the caller. At higher temperatures, great tits produce fewer mobbing vocalizations and approach the loudspeaker broadcasting mobbing calls less often.

Year-round weather alters nest-provisioning rates in a migratory owl.

As global temperatures and precipitation become more extreme, habitat specialists are at particular risk of being pushed past their environmental tolerance limits. Flammulated Owls (Psiloscops flammeolus) are small migratory owls that breed in temperate conifer forests of western North America. Their highly specialized nesting and foraging requirements make them indicators of ecosystem health. Using 17 years of nest observations, we investigated how annual weather patterns affected Flammulated Owl nesting and foraging behaviors during the breeding season. We used generalized linear models with a changepoint parameter to evaluate nest provisioning and nestling growth rates in years of extreme temperature and precipitation. We also evaluated how adult mass, division of labor, and productivity varied based on precipitation and temperature. Compared to wet and warm years, adults made more frequent prey deliveries to nestlings in dry and cold years, particularly early in the night and early in the season, and they experienced earlier changepoints in these years. We found a significant effect of temperature on the number of fledglings in broods, but weather did not affect other variables including productivity, nestling growth rates, adult masses, and division of labor. Our findings suggest that extreme annual weather patterns influence insect prey availability during the Flammulated Owl breeding season, forcing adults to work harder to provision for nests during dry and cold years. While productivity and nestling growth did not vary between years, these may incur a long-term tradeoff in adult survival.

Current temperatures limit the potential impact of a commonly traded predatory gastropod

The pet trade has facilitated the spread of invasive alien species (IAS) globally, with negative consequences for biodiversity. The prediction of impacts is a major goal for invasion ecologists, and is especially crucial in an industry often lacking knowledge about traded species. We focused on the predatory gastropod Anentome helena, a species originating in south-east Asia and traded around the world, but with taxonomic uncertainty. We first set out to determine where our study organism fell within the A. “helena” species complex, known to comprise at least four cryptic species, before assessing the effect of temperature on the number of prey, the pulmonate snail Physella acuta, killed per predator via functional response experiments at two temperatures. We used 22 °C as a recommended temperature for housing the species in captivity, and 18 °C as a representative summer lake temperature in temperate climates of Europe. We also assessed the role of predator group size (1×, 2×, 3×) on predation (total consumption and average per capita consumption) at the experimental temperatures with fixed densities of prey, as well as the effect of these temperatures on prey activity. Our organisms belonged to a cryptic species originating from Thailand (Anentome sp. A), matching the findings of aquarium trade samples in other continents. In the functional response experiments, we found maximum feeding rate to be significantly reduced at the lower temperature. A similar result ensued from group feeding, with total consumption significantly reduced and the reduction in average per capita consumption approaching significance at the lower temperature. There was no significant effect of group size on the average per capita consumption in the group trial, indicating neutral conspecific interactions. No significant effect of temperature on the activity of the prey species was found, suggesting decreased consumption was mainly driven by predator, rather than prey. These results suggest limited A. helena impacts in the short-term, but increasing temperatures with climate change may facilitate greater consequences from releases. We suggest future studies assess other potential predatory impacts and survival across relevant abiotic conditions, and encourage the use of similar methods to assess the impacts of other commonly traded species.

The premise of temperature effect playing in regions with complex moisture sources – Evidence from high-resolution water vapor isotopes

Atmospheric precipitation has widely taken part in the formation and accumulation of many geological archives. In these processes, the isotope fractionations are tightly related to the meteorological factors, such as temperature and precipitation amount. Therefore, precipitation isotopes are usually regarded as an effective proxy to reconstruct the paleoclimate and paleoenvironmental changes. However, with the deepening of research, it is found that the temperature effect is not suitable for all regions and time scales, especially in regions with complex moisture sources. Moreover, the applicable mechanism of the temperature effect is still unclear. Here, we chose Xi’an as our study site, because it is located in the transition zone of the East Asian Summer Monsoon (EASM) and the westerlies with relatively complex water vapor sources. Through conducting a three-year, high-resolution, relatively continuous water vapor isotopic composition measurements in Xi’an, we defined the duration of the EASM here, which normally starts in June and is over in September. By separating the δ18Op into monsoon and non-monsoon seasons, we found a significant temperature effect in the non-monsoon seasons, with a correlation coefficient of 0.54, while no temperature effect is observed in the monsoon seasons and the whole year. Our water vapor isotopic results suggested that the establishment of temperature effect of precipitation isotopes should follow two prerequisites: 1. single water vapor source; 2. large temperature gradient. Our results specify the applicable conditions of temperature effect and potentially help us to better use precipitation isotopes to understand the paleo-temperature variations in different regions.

Quantum chemical mechanism on the depletion of C3O by oxygen atoms: barrierless to produce CO

ABSTRACT Accurate quantum chemical studies at the CCSD(T)/CBS//CCSD/cc-pVTZ level predicted the depletion reaction of C3O by both singlet and triplet O-atoms to be barrierless, leading to the astrophysically very abundant CO plus triplet CCO. The barrierless nature of the reaction fully complied with the long conjecture, whereas the product differed significantly. Our kinetic calculations indicated that the reaction possesses significant negative temperature effect below 30 K. The calculations should be useful for understanding the astrophysical recycling for both the carbon and oxygen species.

Influence of abiotic factors on seasonal and non-seasonal emergence of Tasar silkworm, Antheraea mylitta Drury

Aim: The present study was carried out to introspect the effect of temperature, humidity and rainfall on the emergence of Antheraea mylitta Drury. Methodology: An experiment on seasonal and non-seasonal emergence was carried out in 2019 and 2020 at Kathikund and Kharsawan of Jhakhand, India. Meteorological parameters (temperature, humidity and rainfall) were noted twice daily. Similarly number of adult moths emerged were age-graded and segregated as male and female. They were counted twice in a day within the grainage buildings (preservatory of seed cocoons). Results: The emergence of Antheraea mylitta varied month wise following: June to September, March to May, and November to February. Although the emergence of male individuals was more compared to females, no significant difference was observed statistically. Further increase in rainfall (57%) – humidity (15%) triggered more non-seasonal emergence of females. A strong positive correlation between humidity and rainfall with the emergence of adult moths compared to temperature throughout the year across both the seasonal (June-October) and non-seasonal (November-May) months was observed. The erratic/non-seasonal emergence was strongly correlated with humidity (0.75) compared to rainfall (0.32) and temperature (0.19). Daily emergence differed significantly (p<0.01) between the seasonal and non-seasonal months. Interpretation: During seasonal months, the number of adult moths emerged remained almost constant; however in non-seasonal months, the pattern of adult emergence exhibited a non-linear interrupted by sudden intervals of zero emergence. The intervals corresponded significantly to the effect of humidity and rainfall (p<0.001), however, no significant effect of temperature (p>0.05) was observed. Key words: Abiotic factors, Antheraea mylitta, Seasonal emergence, Tasar silkworm

Initial growth of tungsten fuzz induced by bubble-driven surface stress layer under helium irradiation

Low-energy, high-flux He exposure to tungsten (W) surface leads to the formation of surface nanostructures and severe morphological changes, which may eventually erode the W divertor and threaten the operation of the reactor. In this study, the response of polycrystalline W under low-energy He+ irradiation at different temperatures has been investigated in order to analyze the early stage of nanostructure formation. It is found that the interactions of high-density over-pressured He bubbles result in the formation of surface stress layers. The significant effect of temperature on the surface stress leads to differences in the incubation dose of W fuzz growth. The interaction between the planar network and the underlying W matrix is weak under surface stress, and the W fuzz grows on the surface once the stress reaches a threshold. Thereafter, tensile stress-driven cracking causes the 3D growth of W nanofibers.

CH4 and N2O Emission and Grain Yield Performance of Three Main Rice-Farming Patterns in Central China

This study focuses on the development of more cropping systems in response to global warming and food security concerns. A two-year field experiment (2017–2018) was conducted to investigate the effects of greenhouse gases (GHGs), soil environmental factors and yield on traditional double-cropping rice (DR), maize rice (MR) and ratooning rice (Rr). The results showed a significant annual effect of temperature and rainfall on GHG emissions under different cropping systems. Annual CH4 emissions under MR and Rr were significantly lower than under DR. Compared to DR, the highest cumulative N2O emissions were observed in MR (14.9 kg·ha−1) with a reduction of 23.7% in Rr. In addition, the upland crops significantly reduced CH4 emissions for late rice, while N2O emissions increased by 20.6%. Compared with DR and Rr, global warming potential (GWP) and greenhouse gas intensity (GHGI) were significantly lower for MR (p < 0.05). Meanwhile, the annual yield of MR (16.40 t·ha−1) was 8.1% and 2.4% higher than that of DR and Rr, respectively. This study further found that soil temperature and NH4+-N content were positively correlated with CH4 and N2O emissions, and soil moisture was positively correlated with N2O emission. Thus, we concluded that MR has the greatest potential to improve crop yield and mitigate GHG emissions in central China.

Regional variation in deadwood decay of 13 tree species: Effects of climate, soil and forest structure

Deadwood provides important ecological and biogeochemical functions in forest ecosystems. These functions rely on tree species-specific decay dynamics, but only few studies investigated how exogenous parameters affected the decay of deadwood at the regional scale. Here, we explore the influence of climate, soil traits and forest structure on decay dynamics and mass loss of logs of 13 tree species in 29 plots across three regions in Germany. This long-term experiment (BELongDead) comprises 1,066 logs of 9 angiosperms and 4 gymnosperms and covers a decay time of almost 10 years. Mass loss of logs was relatively high for the temperate climate with partly different half-lives ranging from 6 to 13 years (mean 8.9 ± 2.2 years). Diffuse-porous angiosperms lost 70 ± 13 % of their initial mass, followed by gymnosperms (49 ± 16 %) and ring-porous angiosperms (46 ± 12 %) within the study period. We applied three different mathematical models to fit mass loss in time and found that a linear model is most appropriate for 10 tree species. A sigmoidal model best described the mass loss of Fraxinus, Quercus and Pinus logs. A multivariate analysis revealed a significant effect of soil, temperature and precipitation on mass loss at the plot level. Mass loss increased with decreasing soil nutrient content, possibly as a result of enhanced bidirectional element translocations between nutrient-poor soils and logs by fungal hyphae. Temperature had a positive effect on mass loss, whereas increasing precipitation and soil moisture were negatively related to mass loss. The region with warmer, moderately humid climate and unfavourable soil properties led to overall higher mass loss (66 ± 4 %) whereas the other two regions were indifferent (both 57 ± 3 %). Forest structure, including canopy cover, share of coniferous trees and the stock of deadwood in the vicinity of the logs explained only a small part of the variability in mass loss. High variability within individual tree species suggests that other factors such as organismic diversity and microbial activity have stronger impact on the decay process at the regional scale than exogenous factors.

Studies on Aspergillus flavus on Tiger Nut (Cyperus esculentus) Incubated at Different Regimes of Light and Two Temperatures

An experiment was carried out to ascertain the effect of light regimes (continuous day light, continuous darkness and alternating day light and darkness) on the growth of A. flavus on tiger nut at temperature of 28oC and 30oC. The experiment was a 2 x 3 factorial laid out in a completely randomized design (CRD) replicated 10 times. A. flavus was isolated from naturally infected tiger nuts obtained from different sellers at Delta Park, Abuja Park and Choba campus, University of Port Harcourt, Rivers State, Nigeria. The isolation and sub-culturing were done using Malt Extract Agar (MEA). A tiger nut-based-medium (15ml/Plate) was centrally inoculated with 6-day-old inoculums of A. flavus and incubated appropriately. Assessment of fungal growth was done daily for 10 days and mycelia diameter and mycelia growth rate obtained from the data. Result from the statistical analysis showed that the effect of light regime and temperature on the mycelia diameter of A. flavus was highly significant (P<0.001) and the interaction between light regime and temperature was also significant (P<0.0.01). Growth rate also showed significant (P<0.001) main effect of temperature and light regime and the light regimes x temperature was also significant (P=0.03). The highest mycelia growth rate and mycelia diameter occurred in continuous day light, followed by continuous darkness and finally alternating day light and darkness, with all higher at 30oC. Thus, storage of tiger nut under continuous day light and/or at temperature 28oC and above should be discouraged, in order to reduce microbial spoilage caused by Aspergillus flavus.

Isolation of a new Aspergillus iranicus strain from the soil of southwestern Algeria exhibiting potential palm date-cellulose degrading activity

Microorganisms with biotechnological properties are needed for transformation or degradation of biological products. Here we isolated a new Aspergillus strain (MS-34) from the soil of southwestern Algeria and found that it is related to Aspergillus iranicus. The MS-34 was examined for possible biotechnological properties and we found it to be highly efficacious at degrading palm date cellulose following fermentation. Pretreatment fermentation of palm in 50 % generated the highest (197.84 mg/L) carbohydrate concentration. Pretreatment with 20% KOH produced a maximum 112.97 IU/ml and 47.62 IU/ml for endoglucanase and exoglucanase activities respectively. Besides, glucose and proteins concentration in batch fermentations with 1% CMC medium fluctuated between 86.41 mg/l to 108.85 mg/l and the protein level was 0.713- 0.991 mg/ml. There were significant temperature and pH effects on the enzymatic activity and the optimal temperature conditions were found to be 50-60°C and pH 4.0. Since palm dates are one of the massive agricultural products of the Southeastern and Southwestern Algeria, use of this strain for transformation of palm tree waste will be an advanced biotechnology tool that will contribute to significantly reduce pollution linked to waste incineration. In addition, resulting fermentation products may be used as sources of energy.

Interactive Effect of Dietary Gamma-Aminobutyric Acid (GABA) and Water Temperature on Growth Performance, Blood Plasma Indices, Heat Shock Proteins and GABAergic Gene Expression in Juvenile Olive Flounder Paralichthys olivaceus.

Gamma-aminobutyric acid (GABA) is an important inhibitory neurotransmitter in the central nervous system of living organisms and has the ability to reduce the magnitude of stress in humans and animals. In this study, we evaluated the supplemental effects of GABA on normal and high water temperature based on growth, blood plasma composition as well as heat shock proteins and GABA-related gene expression in juvenile olive flounder. For this, a 2 × 2 factorial design of experiment was employed to investigate the dietary effects of GABA at 0 mg/kg of diet (GABA0 diet) and 200 mg/kg of diet (GABA200 diet) in water temperatures of 20 ± 1 °C (normal temperature) and 27 ± 1 °C (high temperature) for 28 days. A total of 180 fish with an average initial weight of 40.1 ± 0.4 g (mean ± SD) were distributed into 12 tanks, of which, each tank contained 15 fish based on the 4 dietary treatment groups in triplicate. At the end of the feeding trial, the results demonstrated that both temperature and GABA had significant effects on the growth performance of the fish. However, fish fed the GABA200 diet had a significantly higher final body weight, weight gain and specific growth rate as well as a significantly lower feed conversion ratio than the fish fed the GABA0 diet at the high water temperature. A significant interactive effect of water temperature and GABA was observed on the growth performance of olive flounder based on the two-way analysis of variance. The plasma GABA levels in fish were increased in a dose-dependent manner at normal or high water temperatures, whereas cortisol and glucose levels were decreased in fish fed GABA-supplemented diets under temperature stress. The GABA-related mRNA expression in the brains of the fish such as GABA type A receptor-associated protein (Gabarap), GABA type B receptor 1 (Gabbr1) and glutamate decarboxylase 1 (Gad1) were not significantly affected by GABA-supplemented diets under normal or temperature stressed conditions. On the other hand, the mRNA expression of heat shock proteins (hsp) in the livers of the fish, such as hsp70 and hsp90, were unchanged in fish fed the GABA diets compared to the control diet at the high water temperature. Collectively, the present study showed that dietary supplementation with GABA could enhance growth performance, and improve the feed utilization, plasma biochemical parameters and heat shock proteins and GABA-related gene expression under the stress of high water temperatures in juvenile olive flounder.

Experimental and simulation analysis of thermal behavior of large‐span roof system under solar radiation

SummaryThe large‐span metal roof systems can produce a significant nonuniform temperature effect under solar radiation, leading to potential safety hazards. An experiment is conducted to study the nonuniform thermal behavior of a small‐scale continuous welded stainless steel roof (CWSSR) system under solar radiation. The small‐scale CWSSR system considered different roof slopes and sunward side and nightside. The efficiency of the numerical analysis of the thermal behavior of the roof slab is verified in comparison with the experimental results. Based on the numerical and experimental results, the thermal effect of a full‐scale CWSSR system is studied under different orientations, wind speeds, and atmospheric temperature. Through the analysis of research results, the nonuniform thermal features of the CWSSR system are significant and cannot be overlooked. The temperature difference between the sunward side and nightside roof slab is positively correlated with the roof slope. The thermal behavior of the CWSSR system is greatly influenced by wind speeds but is less affected by orientations and atmospheric temperature.

Polymer dispersed liquid crystals devices: role of photopolymerisation to control defect orientation, optical and electro-optical properties

ABSTRACT We are reporting the effect of polymer dispersion on liquid crystals (LCs) by examining their structural, morphological and electro-optic properties. Ultraviolet irradiation effect has been investigated through morphological and electro-optic characteristics and perceived structural behaviour transformation in the respective devices, which persuade topological restraints in the form of defects (photopolymerisation and chemical interaction provoke the development of frozen network which leads to packing of LC molecules in different orientations and defect geometries). We have observed the effect of temperature and voltage on morphological studies via optical micrographs under polarising optical microscopy. A significant effect of polymer concentrations and temperature has been observed on the physicochemical properties of polymer-dispersed liquid crystal (PDLC) systems. The development of defects can be understood via possible theoretical chemical interactions, polymerisation and anchoring energy. A relative optical transmittance and lower threshold voltage has been presented for all the respective PDLC devices in comparison to the pure LC. A higher anchoring (10−5 J/m2) and contrast (18.34 dB) have been noticed in the PDLC devices. Refractive indices and corresponding birefringence have also been measured and compared for pure and doped LC systems. Furthermore, these investigations offer an understanding of essential mechanisms to develop potential electronic materials and optical device applications.

Characterization of Gelidium corneum’s (Florideophyceae, Rhodophyta) vegetative propagation process under increasing levels of temperature and irradiance

Climate change is affecting Gelidium corneum (Hudson) J.V. Lamouroux fields in the Bay of Biscay by reducing its cover and biomass. Understanding those changes requires a good characterization of the responses of this species to different stressors, particularly the effects on key processes such as the vegetative propagation. Here, we aimed to characterize the interactive effect of temperature (15, 20 and 25 °C) and irradiance (5–10, 55–60 and 95–100 μmol*m−2*s−1) on two phases of the vegetative propagation process: the re-attachment capacity and the survival of re-attached fragments. The study findings revealed significant effects of both temperature and irradiance in the re-attachment capacity of the species, with higher rates of attachment registered at 20 °C and 5–10 μmol*m−2*s−1 after 10, 20 and 30 days of culture. However, the interaction effects were not significant at any time interval. At higher or lower temperatures and increasing irradiances, the attachment capacity was reduced. On the other hand, irradiance was demonstrated to be the main factor controlling the survival of rhizoids. In fact, higher levels of irradiance generated severe damage on rhizoids, and thus, conditioned the development of new plants. According to this, it seems clear that the vegetative propagation process of this species is expected to become more vulnerable as both variables are expected to rise due to climate change. An increased vulnerability of this species may have several implications from an ecological and economic perspective, so we encourage to continue exploring the factors and processes controlling its distribution in order to adopt better management actions in the future.

Effects of the type of lactic acid bacteria, hot-pressing temperature, and moisture content of fermented bamboo residue on the properties of self-bonding common particleboards

Self-bonding bamboo particleboards were prepared via hot pressing of bamboo residue fermented by lactic acid bacteria. An orthogonal experiment was designed to investigate the effects of three factors (type of lactic acid bacteria used for fermentation, moisture content (MC) of the fermented residue, and hot-pressing temperature) on the resulting self-bonding particleboards. The bending strength and internal bonding strength of the prepared self-bonding particleboards were tested. Fracture characterization was performed on the cross-section of the prepared self-bonding particleboards after bending breakage. The hot-pressing temperature, moisture content (MC), and type of lactic acid bacteria of the fermented residue had a significant effect on the mechanical strength of self-bonding particleboards, and with increased hot-pressing temperature, the strength of self-bonding particleboards increased. Analysis of the cross-sectional morphology and porosity confirmed the significant effect of hot-pressing temperature on the density distribution of self-bonding particleboards. The self-bonding particleboard produced at the hot-pressing temperature of 180 °C, MC of 30%, and that used Lactobacillus plantarum as a fermentation strain showed the best overall performance and reached Chinese standard requirements for common particleboards.

Physiochemical Changes of European Pear cv. Conference and Asian Pear cv. Yali during Cold Storage

This study evaluated the physiochemical changes of one commercial European pear variety ‘Conference’ and one Asian pear variety ‘Yali’ during 60 days of storage at 1 °C. Content of organic acids, ethylene and formation of CO2 were determined using HPLC/UV-VIS and GC/FID and TCD detectors, respectively. This study presents an evaluation of the influence of the above-mentioned factors and long-term storage on quality parameters, including the antioxidant capacity of an important European and Asian pear cultivar. There was a significant effect of temperature on respiration rate in both varieties. Development of the respiration intensity had a similar course in European and Asian pears. The high values of CO2 production at the beginning of storage for the variety ‘Conference’ (14.08 mg·kg−1·h−1) and ‘Yali’ (23.37 mg·kg−1·h−1) were followed by a sharp decline of 80% and 83% at later stages of storage at 1 °C, respectively. Ethylene formation in fruit increased with storage time and was the highest after 60 days in cold storage, especially in ‘Yali’ (7.14 µL·kg−1·h−1). The results show the relation between ethylene formation and ripening-related fruit parameters. The ‘Yali’ variety showed negligible changes in soluble solids content and flesh firmness during storage ranging from 0.35 to 0.60 MPa. The most represented sugar determined enzymatically was fructose and malic acid was the dominant organic acid in pear fruit. Antioxidant activity determined using the FRAP and DPPH methods did not change significantly during 60 days of storage.

Twenty-eight years of ecosystem recovery and destabilisation: Impacts of biological invasions and climate change on a temperate river

Most river ecosystems are exposed to multiple anthropogenic stressors affecting the composition and functionality of benthic communities. Identifying main causes and detecting potentially alarming trends in time depends on the availability of long-term monitoring data sets. Our study aimed to improve the knowledge about community effects of multiple stressors that is needed for effective, sustainable management and conservation. We conducted a causal analysis to detect the dominant stressors and hypothesised that multiple stressors, such as climate change and multiple biological invasions, reduce biodiversity and thus endanger ecosystem stability. Using a data set from 1992 to 2019 for the benthic macroinvertebrate community of a 65-km stretch of the upper Elbe river in Germany, we evaluated the effects of alien species, temperature, discharge, phosphorus, pH and abiotic conditional variables on the taxonomic and functional composition of the benthic community and analysed the temporal behaviour of biodiversity metrics. We observed fundamental taxonomic and functional changes in the community, with a shift from collectors/gatherers to filter feeders and feeding opportunists preferring warm temperatures. A partial dbRDA revealed significant effects of temperature and alien species abundance and richness. The occurrence of distinct phases in the development of community metrics suggests a temporally varying impact of different stressors. Taxonomic and functional richness responded more sensitively than the diversity metrics whereas the functional redundancy metric remained unchanged. Especially the last 10-year phase, however, showed a decline in richness metrics and an unsaturated, linear relationship between taxonomic and functional richness, which rather indicates reduced functional redundancy. We conclude that the varying anthropogenic stressors over three decades, mainly biological invasions and climate change, affected the community severely enough to increase its vulnerability to future stressors. Our study highlights the importance of long-term monitoring data and emphasises a careful use of biodiversity metrics, preferably considering also community composition.