Search Results (3,577)

Eighty-four autumn (ACS, n = 45)- and spring (SCS, n = 39)-calved multiparous early lactation Holstein cows were assigned to groups of either: (a) grazing + mixed ration (MR) during partial confinement in outdoor soil-bedded pens with shade (OD-GRZ); (b) grazing + MR during partial confinement in a compost-bedded pack barn with cooling (CB-GRZ); or (c) total confinement fed a totally mixed ration (CB-TMR) in a compost-bedded pack barn. Data were analyzed using the SAS MIXED procedure with significance at p ≤ 0.05. In both seasons, despite behavioral differences (p < 0.05) between the OD-GRZ and CB-GRZ groups (i.e., standing, first grazing meal length, bite rate), the milk and component yields, DM intake, microbial CP output (MCP) and NE efficiency were unaffected by the housing conditions, possibly due to mild weather conditions. The milk yield was substantially higher in the CB-TMR group versus the OD-TMR and CB-TMR groups (p < 0.01) in both ACS (~35%) and SCS (~20%) despite there being no intake differences, without any impact on milk component levels. In ACS, this was associated with a higher MCP, likely due to the higher nutritional value of TMR compared to pasture, which was not the case in SCS. In conclusion, the OD-GRZ group achieved the same milk production as the CB-GRZ group through behavior adaptation, under mild weather conditions, in both calving seasons. The CB-TMR group outperformed the grazing systems in both calving seasons, regardless of the MCP. Full article

Many scholars have used samples of drying soil to observe the amount of soil condensation water, which may have exaggerated the amount of regional condensation water, as the soil water content in the natural state was not considered. To analyze the effect of soil moisture content on soil condensation in the natural state, the soil condensation volume in loess and sandy soil under different gravimetric moisture content conditions was measured in the autumn of 2022 and spring of 2023 using micro-lysimeters combined with the weighing method at the groundwater and environment site of Chang’an University, Guanzhong Basin, China. The results showed that the average daily condensation of loess under 0%, 3%, 7%, 11%, and 15% moisture content conditions was 0.34, 0.09, 0.01, −0.05, and −0.07 mm with the condensation days of 54, 40, 24, 21, and 16, respectively, and that of sandy soil was 0.21, −0.02, −0.28, −0.82, and −1.35 mm with condensation days of 54, 24, 2, 3, and 1, respectively. Under the same moisture content conditions, loess had more condensation and condensation days than sandy soil. Soil condensation water occurred mainly when the water content was less than 7%, and it was negatively correlated with soil water content. The quantity of soil condensation water was positively correlated with relative humidity and negatively correlated with air temperature–dew point differences. Relative humidity exceeding 60% and air temperature–dew point differences below 8 °C were more favorable for the formation of soil condensation water. This study provides a reference for the assessment of soil condensation in the natural state. Full article

Mistletoes are hemiparasites that modify how trees cope with drought by impairing the relationships between water, carbon, and nutrients within the tree. Thus, mistletoes endanger the vitality and persistence of trees in drought-prone regions, such as the Mediterranean Basin. Here, we evaluated radial growth patterns and drought sensitivity of Aleppo pine (Pinus halepensis Mill.) trees from which mistletoe was removed ca. two decades ago (MRTs) with control; currently infested trees (MCTs) from a semi-arid region in NE Spain. Growth showed negative trends in both tree classes since the 1980s concurrent with progressive aridification and aggravated by mistletoe infestation, as indicated by the positive effect of mistletoe removal on the growth of MRT trees. Water availability during the previous autumn and winter and current spring and early summer drove growth. Climate–growth correlations were similar between tree classes before treatment, but after mistletoe removal, precipitation became significant in MCT trees but not in MRT trees. Likewise, the impact of drought on growth changed through time: it increased until the late 20th century and then decreased in the MRT trees, which showed higher resistance and resilience against post-treatment droughts. This study provides evidence of the long-term positive effect of mistletoe removal on radial growth in semi-arid pine forests. Full article

Marine aerosol particles can act as cloud condensation nuclei and influence the atmospheric boundary layer by scattering solar radiation. The interaction of ocean waves and coral reefs may affect the distribution and size of marine aerosol particles. Measuring this effect has proven challenging. Here, we tested the hypothesis that the distribution and size of marine aerosol particles would vary over three distinct zones (i.e., coral lagoon, surf break, and open water) near One Tree Island in the Great Barrier Reef, which is approximately 85 km off the east coast of Australia. We used a modified DJI Agras T30 drone fitted with a miniaturised scanning electrical mobility sizer and advanced mixing condensation particle counter to collect data on aerosol size distribution between 30 and 300 nm at 20 m above the water surface. We conducted 30 flights over ten days during the Austral summer/autumn of 2023. The fitted bimodal lognormal curves indicate that the number concentrations for aerosols below 85 nm diameter are more than 16% higher over the lagoon than over open water. The average mean mode diameters remained constant across the different zones, indicating no significant influence of breaking waves on the detected aerosol size modes. The most influential explanatory variable for aerosol size distribution was the difference between air temperature and the underlying sea surface, explaining around 40% of the variability. Salinity also exhibited a significant influence, explaining around 12% of the measured variability in the number concentration of aerosols throughout the campaign. A calculated wind stress magnitude did not reveal significant variation in the measured marine aerosol concentrations. Overall, our drone-based aerosol measurements near the water surface effectively characterise the dynamics of background marine aerosols around One Tree Island Reef, illustrating the value of drone-based systems for providing size-dependent aerosol information in difficult-to-access and environmentally sensitive areas. Full article

The past three decades have seen an increasing number of emerging arthropod-borne viruses in temperate regions This process is ongoing, driven by human activities such as inter-continental travel, combined with the parallel emergence of invasive arthropods and an underlying change in climate that can increase the risk of virus transmission and persistence. In addition, natural events such as bird migration can introduce viruses to new regions. Despite the apparent regularity of virus emergence, arthropod-borne viruses circulating in temperate regions face the challenge of the late autumn and winter months where the arthropod vector is inactive. Viruses therefore need mechanisms to overwinter or they will fail to establish in temperate zones. Prolonged survival of arthropod-borne viruses within the environment, outside of both vertebrate host and arthropod vector, is not thought to occur and therefore is unlikely to contribute to overwintering in temperate zones. One potential mechanism is continued infection of a vertebrate host. However, infection is generally acute, with the host either dying or producing an effective immune response that rapidly clears the virus. There are few exceptions to this, although prolonged infection associated with orbiviruses such as bluetongue virus occurs in certain mammals, and viraemic vertebrate hosts therefore can, in certain circumstances, provide a route for long-term viral persistence in the absence of active vectors. Alternatively, a virus can persist in the arthropod vector as a mechanism for overwintering. However, this is entirely dependent on the ecology of the vector itself and can be influenced by changes in the climate during the winter months. This review considers the mechanisms for virus overwintering in several key arthropod vectors in temperate areas. We also consider how this will be influenced in a warming climate. Full article

Triadica sebifera is an important landscaping tree species because of its colorful autumn leaves. In recent years, some cultivars have been bred and licensed, but it can be difficult to identify them from their morphological traits due to their similar phenotypes. To explore the genetic relationships and construct a fingerprint of the cultivars, the licensed T. sebifera cultivars were analyzed using SSR markers. A total of 179 alleles were identified among the 21 cultivars at 16 SSR loci, and these alleles exhibited a high level of genetic diversity (He = 0.86). The genetic variations mainly occurred among cultivars based on an analysis of molecular variance (AMOVA). According to phylogenetic analysis, principal coordinate analysis (PCoA), and Bayesian clustering analysis, the genetic relationships were independent of geographic distances, which may be mainly due to transplantations between regions. Some cultivars with different leaf colors showed obvious genetic differentiation and may be preliminary candidates for cross-breeding. Finally, the fingerprint for the licensed cultivars was constructed with two SSR markers. The results of this study can provide technical support for the application and legal protection of licensed Triadica sebifera cultivars. Full article

Bacteria and archaea are foundational life forms on Earth and play crucial roles in the development of our planet’s biological hierarchy. Their interactions influence various aspects of life, including eukaryotic cell biology, molecular biology, and ecological dynamics. However, the coexistence network patterns of these microorganisms within natural river ecosystems, vital for nutrient cycling and environmental health, are not well understood. To address this knowledge gap, we systematically explored the non-random coexistence patterns of planktonic bacteria and archaea in the 6000-km stretch of the Yangtze River by using high-throughput sequencing technology. By analyzing the O/R ratio, representing the divergence between observed (O%) and random (R%) co-existence incidences, and the module composition, we found a preference of both bacteria and archaea for intradomain associations over interdomain associations. Seasons notably influenced the co-existence of bacteria and archaea, and archaea played a more crucial role in spring as evidenced by their predominant presence of interphyla co-existence and more species as keystone ones. The autumn network was characterized by a higher node or edge number, greater graph density, node degree, degree centralization, and nearest neighbor degree, indicating a more complex and interconnected structure. Landforms markedly affected microbial associations, with more complex networks and more core species found in plain and non-source areas. Distance-decay analysis suggested the importance of geographical distance in shaping bacteria and archaea co-existence patterns (more pronounced in spring). Natural, nutrient, and metal factors, including water temperature, NH₄⁺-N, Fe, Al, and Ni were identified as crucial determinants shaping the co-occurrence patterns. Overall, these findings revealed the dynamics of prokaryotic taxa coexistence patterns in response to varying environmental conditions and further contributed to a broader understanding of microbial ecology in freshwater biogeochemical cycling. Full article

Here, we explore the dynamics of the waters of eutrophicated Lake Sevan in the modern period, using MSI Sentinel-2 satellite images of different months in different years (2017–2022) and SAR Sentinel-1 images of similar dates. The main objective of the study is to investigate the spatiotemporal variability of the horizontal circulation of this lake and to establish whether the scheme of cyclonic water circulation in the deep-water part of Large Sevan, given in a number of publications, which does not imply water exchange between its littoral and deep-water zones, corresponds to the real picture of currents in the surface layer of the lake in the summer–autumn period (period of pronounced water stratification and intense phytoplankton bloom). The analysis performed convincingly showed that there is no constant cyclonic gyre on the scale of the deep-water part of Large Sevan (≈20 km) during the period under consideration. In most cases, non-stationary eddy dynamics are observed in Large Sevan, including mesoscale and submesoscale eddies, eddy dipoles (mushroom-shaped flows), and their packings. Often the entire deep-water part of Large Sevan is occupied by a two-cell (dipole) or even three-cell (cyclonic eddy with two anticyclones of similar size) water circulation. The time scale of the observed variability is several days. Such variable water circulation in different months (i.e., with different density stratification of water) of different years in a basin with a fairly homogeneous bottom and a slight indentation of the shoreline raises the assumption that the main reason for the non-stationary dynamics in Large Sevan is the variability of the wind effect on its surface layer. The cyclonic gyre in Small Sevan (8–9 km) is a permanent element of the circulation and maintains its position north of the strait between Small and Large Sevan. This gyre and attached anticyclonic eddies in the southern part of its periphery, as well as cyclonic submesoscale eddies in the northern part of Large Sevan, close to the strait, affect the water exchange between Small and Large Sevan in both directions. An additional objective of the study is a validation of the morphometric parameters of Lake Sevan (level, surface area, and water volume), contained in the near-real time HYDROWEB database, LEGOS, France (June 1995–January 2024), based on their comparison with the corresponding values of these parameters from gauging stations in Armenia. It is shown that, with a qualitative correspondence of the nature of lake level changes according to altimetric and instrumental measurements, its values in the HYDROWEB database exceed the data of gauging stations in most cases by 1–1.5 m in 1995–2012 and 0.5–0.6 m in 2013–2022, while the corresponding surface area and volume values according to HYDROWEB data turn out to be underestimated. Full article

To address the issues of the low usage efficiency and illogical structure in rural regions, this study builds a rural integrated energy system (RIES) that incorporates the complementary use of biogas, wind, and light. For resolving the RIES optimum-low-carbon-economic-dispatch problem, a source–load-cooperative optimal-dispatch strategy is proposed. Firstly, a multi-energy integrated demand response (IDR) model based on time-of-use tariffs and time-varying biogas costs is established on the demand side. Secondly, power-to-gas devices are added on the supply side to optimize the system’s electricity–gas-coupling relationship and increase the wind power output space. Thirdly, an RIES-oriented carbon-trading model is constructed by considering the actual carbon emissions of gas loads and the stepped-carbon-trading mechanism. Finally, an optimal-dispatch model is built with the objective function of reducing the total energy cost, wind abandonment cost, IDR cost, and carbon emission cost, while the problem is transformed into a mixed-integer linear problem and solved using CPLEX 12.9. By setting up four scenarios for example analysis, the results show that on typical days in spring, summer, autumn, and winter, the total operating costs of the stepped-carbon-trading system (Scenario 1), taking into account the source-side power-to-gas (P2G) device and the load-side IDR, are reduced by 12.25%, 11.25%, 12.42%, and 11.56%, respectively, compared to the system without the introduction of the IDR (Scenario 3). In contrast to the system that lacks a P2G device at the source end (Scenario 2), the overall costs are decreased by 4.97%, 3.07%, 5.02%, and 5.36%, but the wind power consumption rates are increased by 11.63%, 7.93%, 11.54%, and 11.65%, respectively. Stepped emission trading (Scenario 1) reduces the total operating costs by 5.12%, 3.15%, 5.21%, and 6.84%, respectively, while reducing the biogas costs by 9.75%, 7.74%, 9.67%, and 9.57%, respectively, in comparison to traditional emission trading (Scenario 4). The example results demonstrate the economics, effectiveness, and reliability of a stepped-carbon-trading system with an integrated P2G load-side energy demand response. Full article

Leaf senescence is essential for the growth and development of deciduous trees in the next season. Larix gmelinii, a deciduous coniferous tree, exhibits its most distinctive feature by turning yellow in the autumn and eventually shedding its leaves, resulting in significant changes in its appearance during the fall. Lysine acetylation plays an important role in diverse cellular processes; however, limited knowledge is available regarding acetylations in the needle senescence of L. gmelinii. In this study, the proteomics and acetylated modification omics of two phenotypic leaves, yellow and green (senescent and non-senescent) needles, were analyzed before autumn defoliation. In total, 5022 proteins and 4469 unique acetylation sites in 2414 lysine acylated proteins were identified, and this resulted in the discovery of 1335 differentially expressed proteins (DEPs) and 605 differentially expressed acetylated proteins (DAPs) in yellow versus green needles. There are significant differences between the proteome and acetylome; only 269 proteins were found to be DEP and DAP, of which 136 proteins were consistently expressed in both the DEP and DAP, 91 proteins were upregulated, and 45 proteins were down-regulated. The DEPs participate in the metabolism of starch and sucrose, while the DAPs are involved in glycolysis and the tricarboxylic acid cycle. Among them, DEPs underwent significant changes in glycolysis and citric acid cycling. Most of the enzymes involved in glycolysis and the citrate cycle were acetylated. DAPs were down-regulated in glycolysis and up-regulated in the citrate cycle. In all, the results of this study reveal the important role of lysine acetylation in the senescence of L. gmelinii needles and provide a new perspective for understanding the molecular mechanism of leaf senescence and tree seasonal growth. Full article

The reproductive cycle of non-native species is indicative of their capacity for dispersal, invasion, and competition, and the alteration in biodiversity. Corbicula spp. are successful invaders of aquatic ecosystems. We studied the reproductive cycle of Corbicula largillierti from a Pampean stream, Argentina, at its southern distribution in South America. Specimens were collected monthly from January 2003 to April 2005 and processed using traditional histological techniques. Three gonadal stages (active gametogenesis, mature, and spawned) were recognized. In the studied population, most individuals were hermaphroditic with a dominant female gonadal portion. The three gonadal stages were observed during the whole sampling period with rapid gonadal recovery; no resting period was observed. Five oocyte spawning events were recognized, occurring in autumn and spring. Expanding the knowledge of reproductive features of the Corbicula largillierti allows the understanding of current distributions. The results highlight the difficulty of identifying patterns of gamete release and spawning behavior in this invasive species, as it is recorded for other Corbicula spp. Full article

Sowing date is a particularly important management option to optimize yields as it determines proper wintering and productivity. During a seven-year field experiment, the response of winter wheat to five different sowing times was studied. The beginning of the dormancy period was determined, and the Growing Degree Day (GDD) requirements for the period from sowing to emergence and from emergence to dormancy were assessed. As the sowing date was delayed, the time from sowing to emergence increased. The minimum optimum temperature during the emergence period was about 12 °C, with a heat requirement of about 125–130 GDD for earlier sowings, ensuring that winter wheat germinated successfully and properly prepared for wintering. The heat requirement for later sowings was higher and reached about 180 GDD when the average temperature of this period was about 8 °C. For the late sowing, the period from emergence to dormancy was too short, so winter wheat did not accumulate the required amount of heat, which had a significant impact on yield. The accumulated temperature from emergence to dormancy must be greater than 100 GDD. The obtained values can be applied in other regions or to choose the appropriate wheat sowing time to reduce yield losses under climate change. Full article

Ballast water represents a significant vector for the transfer of aquatic organisms and chemical pollutants. Although various groups of transported microorganisms can have a negative impact on native species of aquatic fauna, the available literature usually focuses on larger organisms. This is important because microorganisms cause changes in the balanced aquatic environment, including a stable trophic pyramid. The objectives of this study were twofold: (i) to determine the seasonal changes in the microbiota of the ballast water of long- and short-range ships entering the southern Baltic port, with a focus on fish pathogenic microorganisms and (ii) to potentially assess the threat to the ichthyofauna caused by the introduction of these microorganisms into the aquatic environment. The analytical results demonstrated notable variability in microbial density across the samples, contingent on the distance traversed by the ships. The samples of ballast water collected in autumn exhibited the highest microbial density compared to those collected in spring and summer. The samples contained yeast (1.00–2.98 log cfu/mL), mold (1.30–3.26 log cfu/mL), and bacteria (2.18–4.61 log cfu/mL), including amylolytic bacteria (0.95–3.53 log cfu/mL), lipolytic bacteria (0.70–2.93 log cfu/mL), and proteolytic bacteria (0.70–2.39 log cfu/mL). The most prevalent were the Pseudomonas bacteria (0.48–4.40 log cfu/mL), including Pseudomonas fluorescens (0.20–2.60 log cfu/mL. The port waters in spring and summer were primarily characterized by the presence of bacteria belonging to the genus Bacillus. Additionally, the samples exhibited the presence of Intestinimonas, Oceanobacillus, and Virgibacillus bacteria. The short-range vessel samples were populated primarily by bacteria belonging to the genus Bordetella, accompanied by Oligella, Brackiella, and Basilea oraz Derxia, while the ballast water of long-range ships contained mainly Acholeplasma and Clostridium, accompanied by Bacillus, Peptosteptococcus, Intestinibacter, Terrisporobacter, Anaerobacillis, Anaerofustis, Oxobacter, and Listeria. A phylogenetic analysis of the bacteria recorded in the ballast water revealed the presence of species, including Bordetella and Acholeplasma, which can facilitate the colonization of aquatic organisms by pathogenic entities. The results of this study showed that despite the use of water treatment systems on ships, ballast waters carry microorganisms that can negatively impact new environments, including local fish populations (e.g., P. fluorescens). These observations point to the need for further research on the effectiveness of ballast water management systems used to date to minimize the environmental impact of organisms carried in ships’ ballast water to preserve natural resources and environmental sustainability in port waters. Full article

Pelagic stingray (Pteroplatytrygon violacea) is the only species of stingray (Dasyatidae) that utilizes both pelagic and demersal habitats. It is the main bycatch species in pelagic longline fisheries targeting bluefin tuna (Thunnus thynnus) in the Gulf of Lions. In the Mediterranean Sea, their stock structure, behavioural ecology and movements are unknown. For the first time in the Mediterranean, 17 individuals (39–60 cm disc width) were tagged with pop-up satellite archival transmitting tags using a novel method of tag attachment to investigate horizontal and vertical movements. The tags were attached for between two and 60 days. Between the months of July and October, pelagic stingray occupied a temperature range of 12.5–26.6 °C, and a depth range extending from the surface to 480 m. Monthly trends in catch-per-unit-effort (CPUE) of pelagic stingray peaked in August and decreased by late autumn. Pelagic stingray may aggregate on the continental shelf during summer and move southwards in early autumn, and this movement pattern is considered in relation to the reproductive cycle and overwintering. At-vessel mortality was low, but there was varying evidence of post-release mortality, indicating the need for further work. Future work and options for bycatch mitigation are also discussed. Full article

Most canopy-forming macroalgae have disappeared from temperate reefs in southern Japan, one of the ocean warming hotspots, but Sargassum nipponicum is surviving in this region. As this species’ annual shoots emerge from holdfasts during summer, both plant components may be highly tolerant to warm and nutrient-poor conditions in this season. The present study examined the effects of temperature and nutrient conditions on holdfast growth, shoot emergence from holdfasts, and shoot growth in S. nipponicum samples collected in Tanegashima Island, southern Japan. The summer temperature in this region (30 °C) allowed holdfast growth and shoot emergence but inhibited shoot growth. Nutrient-poor conditions had limited effects on the first two parameters but suppressed shoot growth. These results suggested that during warm summers and under nutrient-poor conditions in southern Japan, shoots can emerge from S. nipponicum holdfasts but cannot further grow. Additionally, nutrient loading from a nearby river was higher at the only site dominated by S. nipponicum, than at the other sites where this species was absent on Tanegashima Island. This was observed especially between autumn and winter, implying that such a nutrient-rich environment may contribute to shoot growth in S. nipponicum and to the persistence of its population in the area. Full article