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Differing impacts of livestock farming and ranching on aquatic insect biodiversity: a global meta-analysis
Get PDFRecent studies examining global insect biodiversity trends have shown declines for many terrestrial species but increases in some aquatic species, albeit with limited spatial coverage. However, the impact of a wide range of threats on insect biodiversity remains uncertain at a global scale. Livestock farming and ranching constitute approximately 30% of global land use and represent a major and growing threat to biodiversity. Although we know livestock farming and ranching affect aquatic macroinvertebrates via degradation of water quality and habitat, there are no global syntheses of the impacts of livestock on the biodiversity of aquatic insects. Here, we investigate the impact of livestock farming and ranching on the abundance and richness of five major aquatic insect orders: Ephemeroptera (mayflies), Plecoptera (stoneflies), Trichoptera (caddisflies), Megaloptera (dobsonflies and alderflies), and Odonata (dragonflies and damselflies). Our meta‐analysis shows that livestock farming significantly reduces species richness of Ephemeroptera, Trichoptera, and Plecoptera compared to areas with no livestock present. In contrast, we found no overall impact of livestock farming on the abundance of aquatic insects or individual orders, even after accounting for moderators such as livestock type, riparian vegetation presence, and stocking density. The apparent stability in insect abundance, combined with declines in richness, suggests there may be shifts in community composition that cannot be captured with a broad‐scale analysis. Further research is needed at finer taxonomic resolution, coupled with increased reporting of quantitative stocking density and livestock water access, to better understand the apparently heterogeneous effects of livestock on aquatic insects and predict the impacts of further spread and intensification of livestock farming
Effect of a previous high pathogenicity avian influenza (HPAIV) infection on the breeding success of northern gannets (Morus bassanus)
Get PDFHighly pathogenic avian influenza (HPAIV) caused widespread mortality and breeding failure among many wild, avian populations in Europe and North America in 2021–2023, but most populations exhibited a marked reduction in mortality in the year following an outbreak, suggesting that surviving individuals may have developed immunity. A critical mechanism for population resilience is whether individuals that have survived the disease show reduced breeding success because of the potential costs associated with recovery, notably elevated immune defence. We found that, at two UK colonies, the breeding success of Northern Gannets Morus bassanus with black eyes (an indicator of past exposure to HPAIV) was similar to those with normal blue eyes in the year following a severe disease outbreak, suggesting that population recovery may not be hampered by lower reproductive performance of recovered individuals compared to those that were unexposed. However, breeding success, irrespective of past exposure, was lower than the long‐term average, suggesting potential carry‐over effects on all individuals from the extensive disruption caused by the epidemic the previous year
Freshwater Sources in the Global Ocean Through Salinity‐ δ 18 O Relationships: A Machine Learning Solution to a Water Mass Problem
Get PDFChanges in the hydrological cycle can affect ocean circulation and ventilation. Freshwater enters
the ocean as meteoric water (MW; precipitation, river runoff, and glacial discharge) and sea ice meltwater
(SIM). These inputs are traced using seawater salinity and stable oxygen isotopes in seawater, δ18O. We apply a
self‐organizing map, a machine learning technique, to water mass properties to estimate the global distribution
of the isotopic signature of MW ( δ18OMW) by characterizing distinct salinity‐δ18O relationships from two
comprehensive data sets. The inferred δ18OMW is then used in a three‐endmember mixing model to provide a
globally coherent MW and SIM contributions to the extratropical ocean freshwater budget. Through the use of
δ18O, our results show the role of MW and SIM in dense water formation and the resulting interhemispheric
asymmetry in the freshwater sources that fill the interior ocean freshwater budget. Trends drawn in θ‐S space
show a significant decrease in sea ice formation driving the freshening of Antarctic bottom water for the 1980–
2023 period, whereas SIM is significantly increasing in parts of the Arctic halocline. The different roles of sea
ice in dense water formation has implications for future ocean circulation under climate change, where machine
learning techniques applied to δ18O have been proven to have utility in detecting such changes
The genome sequence of the light arches, Apamea lithoxylaea (Denis & Schiffermüller), 1775 (Lepidoptera: Noctuidae)
Get PDFWe present a genome assembly from an individual female Apamea lithoxylaea (Light Arches; Arthropoda; Insecta; Lepidoptera; Noctuidae). The assembly contains two haplotypes with total lengths of 577.73 megabases and 521.26 megabases. Most of haplotype 1 (98.15%) is scaffolded into 32 chromosomal pseudomolecules, including the W and Z sex chromosomes. Haplotype 2 was assembled to scaffold level. The mitochondrial genome has also been assembled, with a length of 16.43 kilobases. This assembly was generated as part of the Darwin Tree of Life project, which produces reference genomes for eukaryotic species found in Britain and Ireland
Modelling the Lodi, 2023 and Fano 2024, Italy dengue outbreaks: the effects of control strategies and environmental extremes
Get PDFAutochthonous cases of dengue in Europe are increasing. In 2023 (Lodi province) and 2024 (Fano, Pesaro and Urbino province), Italy saw the largest modern dengue outbreaks to date. Public health measures were adopted to mitigate transmission. The efficacy of these measures is unknown. We model the 2023 and 2024 dengue outbreaks to estimate the likely date of introduction of the primary case and efficacy of control measures, exploring explanations for the patterns of dengue cases for the two outbreaks. We apply a climate‐driven mathematical model for Aedes albopictus and dengue virus transmission to the 2023 and 2024 outbreaks, comparing outputs to case data. The model accurately predicts the initial timeline of the Lodi dengue outbreak ( R 2 = 0.83), with a peak in cases in late August 2023, after which the control efforts reduced transmission. The model also accurately predicts the Fano dengue outbreak ( R 2 = 0.65), showing an increase in cases, peaking in mid‐September 2024, after which there was an abrupt fall in cases. Our results suggest this can be attributed to substantial rainfall, and that public health measures may have latterly prevented a second peak in cases. The high predictive and explanatory ability of the model when applied to the Lodi and Fano outbreaks indicates that this framework may be of high value for public health decision‐making for predicting the frequency and magnitude of future dengue outbreaks when coupled with real‐time case data
Groundwater mapping techniques applied in Africa
Get PDFGroundwater maps are an excellent tool for managing and developing groundwater. Maps are useful for advocacy, planning, analysis, monitoring and implementation. However, maps should be designed and developed at the appropriate scale to meet their expressed purpose. In this talk I discuss different methods of mapping and give examples from continental scale to local scale. Although Earth Observation and Machine Learning techniques offer some help, the most helpful data are generally borehole information on transmissivity, water levels and chemistry, combined with good geological map
Microbial Communities in Sediments From Different Landform Systems, Svalbard
Get PDFSvalbard is host to a range of glacier types with different thermal regimes, behaviors and complex hydrological networks and landforms. Here, we hypothesize that the (H1) surge-type glaciers will host different microbial community structures, and that (H2) different landform types will also host different microbial community structures. We further hypothesize that (H3) these differences in microbial communities will result in different concentrations and compositions of extracellular polymeric substances (EPS) in response to potentially different stressors associated with surging behavior (H4) or the formation of different landforms. To test these hypotheses, supra- and subglacial sediments from different glacier types and landforms in southwest and west Spitsbergen were collected (26 locations, across 10 glaciers). 16S rRNA gene amplicon sequencing and epifluorescence microscopy was used to determine the microbial community composition, diversity and biomass. At the sequence level all samples were predominantly different across all glaciers and landforms with only 72/1,268 sequences detected in two or more samples. Diversity indices showed samples generally have similar levels of diversity despite these differences in community structure. The EPS concentrations were also similar (0.34 ± 0.71 mg g−1) at all locations excluding a single outlier, suggesting consistent production of EPS. This has implications for understanding the microbial ecosystem response to changing glacial dynamics as the extent and thermal regimes of glaciers shift due to climate change
Environmental hazards from pollution of antibiotics and resistance-driving chemicals in an urban river network from Malawi
Get PDFAfrican communities have a high prevalence of antimicrobial-resistant bacterial carriage, alongside high levels of antibiotic usage and environmental pollution. Limited access to water, sanitation and hygiene infrastructure and wastewater treatment facilities enables the dissemination of resistant bacteria, antimicrobials and antibiotic resistance-driving chemicals (ARDCs) into local rivers. Few data exist quantifying the chemical drivers of antimicrobial resistance (AMR) in urban aquatic environments from African settings. In this longitudinal surveillance study, we investigated an urban river network in Blantyre, Malawi over a continuous 12-month period, identifying a broad-range of chemical pollutants, including antibiotics, common pharmaceuticals, agricultural and industrial chemicals and heavy metals. Antimicrobial concentrations were found at levels selective for AMR and ARDCs exhibited seasonal variations, indicating that deficient sanitation infrastructure and anthropogenic factors result in high antibiotic and ARDC levels entering the river systems, which serve as an important ecological niche for the acquisition, maintenance and transmission of AMR
Global tipping points report 2025. Implications of overshooting 1.5°C for Earth system tipping points [Chapter 2.3]
Get PDFThe world has entered a new reality. Global warming will soon exceed 1.5°C. This puts humanity in the danger zone where multiple climate tipping points pose catastrophic risks to billions of people. Already warm-water coral reefs are crossing their thermal tipping point and experiencing unprecedented dieback, threatening the livelihoods of hundreds of millions who depend on them. Polar ice sheets are approaching tipping points, committing the world to several metres of irreversible sea-level rise that will affect hundreds of millions. Every fraction of additional warming increases the risk of triggering further damaging tipping points. These include a collapse of the Atlantic Meridional Overturning Circulation (AMOC) that would radically undermine global food and water security and plunge northwest Europe into prolonged severe winters. Together, climate change and deforestation put the Amazon rainforest at risk of widespread dieback below 2°C global warming, threatening incalculable damage to biodiversity and impacting over 100 million people who depend on the forest. These climate tipping point risks are interconnected and most of the interactions between them are destabilising, meaning tipping one system makes tipping another more likely. The resulting impacts would cascade through the ecological and social systems we depend upon, creating escalating damages. Humanity faces a potentially catastrophic, irreversible outcome. The Inter-American Court of Human Rights recognises the right of humans to a safe climate, hence preventing irreversible harm to the climate system is a legal imperative. How hot we let it get and for how long really matters in preventing climate tipping points. The magnitude and duration of global temperature overshoot above 1.5°C has to be minimised. To achieve that, global anthropogenic greenhouse gas emissions must be halved by 2030 (compared to 2010 levels) and then reach net zero by 2050. This requires an unprecedented acceleration in decarbonisation, rapid mitigation of methane emissions and other short-lived climate pollutants and fast scaling of sustainable carbon removal from the atmosphere. If we wait to cross tipping points before we act, it will be too late. The only credible risk management strategy is to act in advance. But the window for preventing damaging tipping points is rapidly closing. Current Nationally Determined Contributions (NDCs) and binding long-term or net zero targets are not enough. They still commit the world to ongoing global warming that will likely exceed 2°C before 2100. This demands immediate, unprecedented action from leaders at COP30 and policymakers worldwide. To achieve such a radical acceleration of action requires triggering positive tipping points that generate self-amplifying change in technologies and behaviours, towards zero emissions. In the two years since the first Global Tipping Points Report was published, there has been a radical acceleration in the uptake of solar power and electric vehicles worldwide. However, there has also been a recent spate of backsliding on commitments in some nations and sectors, including finance. Nevertheless, a minority can still tip the majority when they have self-amplifying feedback on their side. This is clearly evident in clean technology adoption. Solar PV panels have dropped in price by a quarter for each doubling of their installed capacity. Batteries have improved in quality and plummeted in price the more that are deployed. This encourages further adoption. The spread of climate litigation cases and nature positive initiatives is also self-amplifying. The more people undertaking them the more they influence others to act. Positive tipping points are also starting to interact and reinforce one another. Policies targeting super-leverage points of interaction can help trigger this cascading positive change. Reinforcing feedback between civil society and policymakers is also critical to amplifying positive change. Hence the Global Mutirão, by catalysing collective action from civil society, could be key to triggering positive tipping points. Only with a combination of decisive policy and civil society action can the world turn from facing existential climate tipping point risks to seizing positive tipping point opportunities
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