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Decoding Stress Responses in Farmed Crustaceans: Comparative Insights for Sustainable Aquaculture Management
Get PDFAquaculture is a crucial food-producing sector that can supply more essential nutrients to nourish the growing human population. However, it faces challenges, including limited water quality and space competition. These constraints have led to the intensification of culture systems for more efficient resource use while maintaining or increasing production levels. However, intensification introduces stress risks to cultured organisms by, for instance, overcrowding, waste accumulation, and water quality deterioration, which can negatively affect the growth, health, and immunity of animals and cause diseases. Additionally, environmental changes due to climate and anthropogenic activities further intensify the environmental stress for aquaculture organisms, including crustaceans. Shrimp are one of the most widely cultured and consumed farmed crustacea. Relative to aquatic vertebrates such as fish, the physiology of crustaceans has simpler physiological structures, as they lack a spinal cord. Consequently, their stress response mechanisms follow a single pathway, resulting in less complex responses to stress exposure compared to those of fish. While stress is considered a primary factor influencing the growth, health, and immunity of shrimp, comprehensive research on crustacean stress responses remains limited. Understanding the stress response at the organismal and cellular levels is essential to identify sensitive and effective stress biomarkers which can inform the development of targeted intervention strategies to mitigate stress. This review provides a comprehensive overview of the physiological changes that occur in crustaceans under stress, including hormonal, metabolic, hematological, hydromineral, and phenotypic alterations. By synthesizing current knowledge, this article aims to bridge existing gaps and provide insights into the stress response mechanisms, paving the way for advancements in crustacean health management
Large-Scale Retrieval and Quality Control of Leaf Area Index Based on ICESat-2 Spaceborne Photon-Counting Laser Altimeter
Get PDFSpaceborne light detection and ranging (LiDAR) provides a promising method for large-scale characterizing leaf area index (LAI). However, the quality of point cloud data from spaceborne LiDAR, especially Ice, Cloud, and land Elevation Satellite-2 (ICESat-2), is susceptible to atmosphere and background noise, introducing considerable uncertainty in LAI retrieval. Thus, efficiently screening out the high-quality point cloud is a significant guarantee for high-quality LAI retrieval. In this study, we proposed a quality control (QC) method that employed the number of 10-m windows without ground points in the ICESat-2 100-m segment as the QC flag. This method divided segments into 11 QC flags from 0 to 10 and was applied to LAI retrieval across Chinese forests from 2019 to 2020. The field measurements at locations identical to ICESat-2 ground tracks were used to validate the ICESat-2 LAI at different QC flags. The results showed that the proposed method effectively improved point cloud quality recognition and LAI accuracy, with ICESat-2 LAI (QC <3) reducing root mean square error (RMSE) by 26.36% compared with all ICESat-2 LAIs. It also showed good agreement with Moderate Resolution Imaging Spectroradiometer (MODIS) and Global Land Surface Satellite (GLASS) LAI and mitigated saturation issues in passive optical imagery. The ICESat-2 LAI with QC <3 performed better in deciduous broadleaved, evergreen needle-leaved, deciduous needle-leaved, and mixed forests (MFs), but not in evergreen broadleaved forests (EBFs). ICESat-2 LAI was particularly adept at capturing high-LAI values, which had the highest proportion of LAI values over 6.0 compared with MODIS and GLASS LAI. The proposed method has the potential for large-scale and high-quality LAI retrieval using ICESat-2 data on a global scale
Ett forskarinspel till den nya landsbygdspolitiken
Get PDFDenna rapport är ett kunskapsunderlag för en omvandlad politik för Sveriges landsbygder. Initialt beskrivs den metod som använts för framskrivningen av detta underlag. Vi kallar det för ett forskarinspel, eftersom det bygger på en process som samlat en bredd av regional- och landsbygdsforskare som, baserat på deras forskning, har hjälpt författarna att formulera 40 olika policyförslag. Lika viktigt som forskarinspelen är den förankring som gjorts med praktiker på olika nivåer, vilken ledde fram till de tio temana i rapporten. Mot en bakgrund av större samhällsrörelser, såsom demografisk utveckling, klimatförändringar och migrationens betydelse för landsbygden, lyfts tio politiska temaområden fram som särskilt viktiga, och bidrar med basen till den diskussion som kännetecknas av behoven av en rättvis och platsanpassad politik som kan hantera de svenska landsbygdernas mångfald och en politik bortom stuprörstänk
Factors affecting detection probability: Insights from banding data in a long-term continent-wide monitoring program
Get PDFBird banding studies are essential for providing critical data on species population demographics and movements, as important components for understanding their ecology and conservation and management applications. However, analysing sightings of banded individuals is often complicated by untested assumptions of the species' behaviour or visibility of the bands, leading to biased populations estimates, especially in large-scale long-term studies. In this study we investigate factors influencing detection rates of colour-banded Eurasian cranes (Grus grus), from a monitoring program spanning 35 years, involving 5049 marked individuals using four different types of bands (ELSA, 'Finnish', 'Spanish' and alphanumeric) with 172,725 resightings along migratory flyways. Data were compiled from European national banding schemes and the internet-based Crane Observation Ring Archive (iCORA). We used capture-mark-recapture mixture models to study the variation in detection probability from differences in the type of bands used, time since marking, year of observation, natal origin and an additional parameter to account for unexplained resighting heterogeneity. All band types showed high detection probabilities in their first years (as high as 80 %) but declined significantly over time, with detection rates halving within 20 years. Although starting with the lowest detection probability, alphanumeric bands remained relatively stable over time. There was a general increase in detection probability over the 35-year study period, which can be attributed to enhanced observation efforts, addition of pictures to reports and improved coordination of reports. Detection also varied by natal country, each population's migratory routes, which were related to differences in monitoring efforts and habitat conditions along the flyways. Our findings emphasize the importance of band type, observation effort, migration pattern and environmental factors in determining detection probabilities, but also the importance to account for unexplained heterogeneity with a mixture model. This study is crucial for the study of demographic parameters within the European crane population and future evidence-based population management
Water buffalo farming, udder health and its dairy production status in Bangladesh: Practices, challenges, and potentialities
Get PDFBuffalo farming in Bangladesh plays a key role in enhancing food security by providing a valuable protein source through milk and meat production. Water buffalo are well-adapted to harsh climate conditions due to their robust immune systems, while they may adapt with minimal feed availability compared to dairy cows. Despite its adaptability and importance, buffalo farming has been underprioritized compared to cattle farming due to several challenges, such as a lack of awareness among farmers of modern dairy practices, limited access to good quality feed, poor breeding programs, improper management practices, and inadequate veterinary services. Furthermore, the lack of a dedicated buffalo product chain, fragmented market, and limited policy support have further impeded the development of this sector, leading to reduced profitability. Despite similar climatic conditions, Bangladesh's buffalo population remains underexploited, contributing minimally to global buffalo milk production. In contrast, several neighboring countries, including India, Pakistan, and Nepal, lead global buffalo milk production, highlighting a significant gap in Bangladesh's buffalo sector. Despite these constraints, buffalo farming holds great potential, particularly for producing high-nutrient products such as yogurt and cheese, which are popular in many regions. Recognizing the potential of buffalo farming, the government and other organizations are collaborating on initiatives such as enhanced breeding programs, policy support, and extension services for farmers. This review highlights the challenges and prospects of water buffalo farming, including the need for strategic interventions and key research areas to exploit the potential in dairy enterprises in Bangladesh
Naturunderstödd rehabilitering på landsbygden – (NUR)
Get PDFRegion Skåne är ledande i Sverige med att erbjuda naturunderstödd rehabilitering, NUR, till personer som söker primärvården på grund av stressrelaterad psykisk ohälsa. NUR erbjuds som stöd i pågående behandling där vården ansvarar för patientens rehabilitering och NUR-leverantören erbjuder hälsofrämjande naturmiljöer och meningsfulla aktiviteter. Konceptet bygger på både nationell och internationell forskning kring naturens betydelse för människors hälsa. NUR i Skåne drivs av Region Skåne i samverkan med Sveriges lantbruksuniversitet. Läs gärna närmare kring NUR i Skåne på www.slu.se/nur och www.1177.se NUR på landsbygden i Skån
Evaluation of biogenic zinc oxide nanoparticles from Sonneratia ovata leaf extract for multivariate factorial photocatalytic and biological activities
Get PDFThe presence of dyes from industrial effluents (such as textile, paper, and leather industries) in water bodies is a significant source of pollution, posing ecological risks that necessitate their removal. The present study demonstrated that the mangrove Sonneratia ovata leaf extract is a promising resource for the biosynthesis of zinc oxide nanoparticles (ZnO NPs), which have potential applications in biomedical fields and wastewater remediation. X-ray diffraction analysis revealed that these nanoparticles have a hexagonal wurtzite structure. Optical measurements indicated the presence of a band gap at 3.19 eV. Morphological studies indicated a mixture of rod-shaped and small spherical nanoparticles. The observed physicochemical properties of the green-synthesized ZnO NPs significantly surpassed the chemically prepared ZnO NPs following a similar synthesis approach. The photocatalytic efficiency of the biosynthesized nanoparticles was tested under UV light irradiation to degrade ethidium bromide dye. This degradation efficiency was shown to be dependent on dye concentration, dye pH, and catalyst concentration. The highest degradation rates of 88.5 %, 98.6 %, and 89.4 % for ethidium bromide dye, respectively, are for dye concentration, dye pH, and nanocatalyst concentration following a first-order kinetic model. Furthermore, the stabilized nanoparticles derived from the green synthesis using S. ovata leaves are potent antioxidants, exhibiting antibacterial activity against Staphylococcus aureus and Escherichia coli. These findings highlighted the potential of using natural aqueous extracts from S. ovata to produce phytochemical-enhanced nanoparticles with significant photocatalytic degradation of toxic dyes in water bodies and biomedical applications
Fragmented forests, isolated fungi: Saproxylic polypores in boreal woodland key habitats
Get PDFForestry in boreal Sweden has significantly altered the landscape and reduced old-growth forests, promoting growth of younger, managed stands. Saproxylic polypores are in direct competition with forestry for resources and have declined significantly in diversity. These fungi play a crucial role in decomposing deadwood with their persistence reliant on habitat quality, connectivity, and continuous wood availability. We examined how log, stand, and landscape-level factors affect saproxylic polypore richness and community composition in 26 woodland key habitats (WKHs) in southern boreal Sweden. We recorded polypore fruitbodies on 1263 Picea abies deadwood units and assessed stand structure. GIS was used to quantify spruce forest amount and quality at 0.5, 5, and 15 km scales, including connections to larger high-quality habitats. Local-scale factors, especially deadwood volume and decay stage, strongly influenced fungal richness. Landscape effects were weaker, likely due to the homogenous and degraded surrounding forest matrix. However, polypore richness increased with high-quality forest cover at the 15 km scale, while medium-quality forest at 5 km had a negative effect. Red-listed species richness showed a strong eastward gradient, possibly reflecting historical forestry and extinction debt. Community composition patterns aligned with these trends, with further indirect effects from nearby forest amount and quality. We conclude that the landscape configuration matters but is context dependant. In our heavily managed study region, high-quality patches like WKHs are too isolated, leaving local conditions as the primary driver of fungal persistence. Effective conservation requires integrating landscape-scale measures, including identifying and protecting remaining forests with high natural values
Nitrogen Fixation Potential in Bathypelagic Sediment of the Ice-Covered Arctic Ocean Revealed Through Long-Term Stable Isotope Incubations
Get PDFDue to climate change, sea ice more commonly retreats over the shelf breaks in the Arctic Ocean, impacting sea ice-pelagic-benthic coupling in the deeper basins. Nitrogen fixation (the reduction of dinitrogen gas to bioavailable ammonia by microorganisms called diazotrophs) is reported from Arctic shelf sediments but is unknown from the Arctic deep sea. We sampled five locations of deep-sea (900-1500 m) surface sediments in the central ice-covered Arctic Ocean to measure potential nitrogen fixation through long-term (> 280 days) stable-isotope (N-15(2)) incubations and to study diazotroph community composition through amplicon sequencing of the functional marker gene nifH. We measured low but detectable nitrogen fixation rates at the Lomonosov Ridge (0.6 pmol N g(-1) day(-1)) and the Morris Jessup Rise (0.4 pmol N g(-1) day(-1)). Nitrogen fixation was observed in sediments with the lowest organic matter content and bacterial abundance, and where sulphate-reducers like Desulfuromonadia and Desulfosporosinus sp. were prominent. Most nifH genes were distantly related to known diazotrophs. In this study, we show a potential for nitrogen fixation in Arctic bathypelagic sediments, considerably extending the known biome of marine nitrogen fixation. It raises the question of the significance of low but potentially widespread nitrogen fixation in deep-sea sediments
Terrestrial planetary plants: Essential preparations for interstellar migration
Get PDFInterstellar migration offers great potential for expanding human habitable space. As a powerful entropy-reducing system, plants convert simple, disordered chemical elements into complex, ordered organic macromolecules. They are expected to grow successfully on some planets and meet the essential nutritional and medical requirements for future interstellar migration. Taking Mars as a model planet, we analyze the basic physical, chemical and biological laws of plant growth on the terrestrial planet and propose terrestrial planetary plants (TPPs) for future terrestrial planetary agriculture (TPA). Biotechnological improvement of 25 TPPs candidates screened from 450,000 plants would reduce the dependence of interstellar migrants on farmland, poultry, livestock and hospitals, thus achieving self-sufficiency in food and medicine on Mars and other terrestrial planets. The TPPs are expected to break the 10 % rule in traditional food chains and provide new insights into enhancing agricultural production and food security on the earth