Department of Energy and Climate Change, UK

Small, isolated populations are often vulnerable to increased inbreeding and genetic drift, both of which elevate the risk of extinction. The Bellinger River turtle (Myuchelys georgesi) is a critically endangered species endemic to a single river catchment in New South Wales, Australia. The only extant wild population, along with the breeding program, face significant threats from viral outbreaks, most notably a nidovirus outbreak in 2015 that led to a 90% population decline. To enhance our understanding of genomic characteristics in the species, including genome-wide and functional gene diversity, we re-sequenced, assembled, and analysed 31 re-sequenced genomes for pure M. georgesi (N = 31). We manually annotated the major histocompatibility complex (MHC), identifying five MHC class I and ten MHC class II genes and investigated genetic diversity across both classes in M. georgesi. Our results showed that genome-wide diversity is critically low in pure M. georgesi, contexualised through comparison with opportunistically sampled backcross animals—offspring of F1 hybrids (M. georgesi × Emydura macquarii) backcrossed to pure M. georgesi (N = 4). However, the variation observed within the core MHC region of pure M. georgesi, extending across scaffold 10, exceeded that of all other macrochromosomes. Additionally, no significant short-term changes in either genome-wide or immunogenetic diversity were detected following the 2015 nidovirus outbreak (before; N = 19, after; N = 12). Demographic history reconstructions indicated a sustained, long-term decline in effective population size since the last interglacial period, accompanied by more recent steep declines. These patterns suggested that prolonged isolation and reduced population size have significantly influenced the dynamics of genome-wide diversity. It is likely that contemporary stressors, including the recent nidovirus outbreak, are acting on an already genetically depleted population. This study offers new insights into genome-wide and immune gene diversity, including immune gene annotation data with broader implications for testudines. These findings provide crucial information to support future management strategies for the species.

Instream structures such as dams and weirs create artificial barriers to the passage of riverine fish, fragmenting their communities and contributing to global declines in freshwater fish biodiversity. Preventing further declines requires the remediation of barriers to restore fish passage, but analysis of fragmented fish communities is necessary to prioritize locations and fish taxa for remediation. Additionally, the potential for high flow events to facilitate barrier drown‐out and reduce fragmentation remains unresolved. We used a meta‐regression analysis to investigate the severity of fish fragmentation in relation to barrier features, fish traits, and river flows, quantifying fragmentation with a novel log response ratio metric reflecting the asymmetry of fish populations around barriers. We discovered that high barriers, barriers which separate different sized habitats, and clusters of sequential barriers cause more severe fragmentation and should be prioritized for remediation. Currently, barrier remediation is focused on improving passage for mobile fishes, but taxa which migrate short distances and have poor swimming performance were most fragmented, suggesting efforts are warranted to improve passage for less vagile fishes. We found evidence that fragmentation was reduced by large river flows which spill onto the floodplain and provide additional connectivity around barriers, particularly in highly regulated sections of stream with many sequential barriers. The findings of this study can be applied to improve the management of fish passage in rivers, an area of increasing relevance with the worsening discontinuity of rivers due to climate change and the continued construction of barriers.

When multiple weather‐driven hazards such as heatwaves, droughts, storms or floods occur simultaneously or consecutively, their impacts on society and the environment can compound. Despite recent advances in compound event research, risk assessments by practitioners and policymakers remain predominantly single‐hazard focused. This is largely due to traditional siloed approaches that assess and manage natural hazards. Hence, there is a need to adopt a more ‘multi‐hazard approach’ to managing compound events in practice. This paper summarizes discussions from a 2‐day workshop, held in Glasgow in January 2023, which brought together scientists, practitioners and policymakers to: (1) exchange a shared understanding of the concepts of compound and multi‐hazard events; (2) learn from examples of science–policy–practice integration from both the single hazard and multi‐hazard domains; and (3) explore how success stories could be used to improve the management of compound events and multi‐hazard risks. Key themes discussed during the workshop included developing a common language, promoting knowledge co‐production, fostering science–policy–practice integration, addressing complexity, utilising case studies for improved communication and centralising information for informed research, tools and frameworks. By bringing together experts from science, policy and practice, this workshop has highlighted ways to quantify compound and multi‐hazard risks and synergistically incorporate them into policy and practice to enhance risk management.

Thickening of woody vegetation has degraded numerous ecosystems globally. In forests, woody thickening often follows gap‐creating disturbance that removes mature trees and promotes the dense recruitment of woody resprouts or seedlings. Restoration thinning seeks to reduce tree densities in thickened forests to hasten recovery of stand structure for habitat and other conservation outcomes. However, as restoration thinning involves gap‐creating disturbance, it may stimulate further recruitment. We investigated recruitment responses to restoration thinning in thickened river red gum ( Eucalyptus camaldulensis Dehnh.) forests on the Murray River floodplain in semiarid south‐eastern Australia by implementing mechanical thinning at various intensities. The average distance between retained trees (up to 15 m) was intended to be insufficient to stimulate further recruitment, and herbicide was applied to cut stumps to reduce resprouting. We recorded seedling abundance annually for 5 years and resprout abundance after 5 years. Resprouting occurred at all levels of thinning intensity. On average, almost one third of the trees affected by thinning resprouted with over three resprout stems per resprouting tree. Thinning that reduced tree densities to below about 400 per hectare also increased seedling abundance by up to 7500 additional seedlings per hectare in some plots in the fifth year of the study when establishment conditions were favorable. These results demonstrate that effective recruitment controls must be identified prior to implementing restoration thinning programs. Without effective recruitment controls, restoration thinning may stimulate more stems than were removed by thinning, and therefore be an ineffective conservation intervention.

It is still unclear to what extent transition risks are being internalized by financial investors. In this paper, we provide a novel investigation of the impact of media‐based measures of transition risks on the credit risk of energy companies, as measured by their credit default swaps (CDS) indices. We include both European and North American markets in the 2010–2020 period. Using linear and non‐linear local projections, we find that a transition risk shock affects CDS indices only when combined with tangible physical climate‐related impacts. We also find evidence of non‐linear cross‐border effects, with North American energy companies particularly affected by European dynamics. We suggest that the public reaction in the wake of severe climate‐related disasters, which might push policymakers to adopt more decisive climate action, contributes to making the transition‐related debate salient in the eyes of credit market actors.

Taxonomic uncertainty in Coronidium has existed since its original circumscription. Recent molecular phylogenetic analyses inferred Coronidium to be non-monophyletic and composed of four distinct clades, leading to the erection of Leucozoma and the confirmation that C. scorpioides (Labill.) Paul G.Wilson and related species are more closely related to other Australian Gnaphalieae. The present study focused on the delimitation of those species inferred to be part of Coronidium, Leucozoma and the closely related Helichrysum leucopsideum DC. We gathered DArTseq single-nucleotide polymorphism data and tested species limits by examining genotypic differences, ancestry, and morphological characters observed on herbarium specimens and living collections. Results support the recognition of four new narrowly endemic species, namely, C. batianoffii T.L.Collins & I.Telford, C. bruhlii T.L.Collins, L. alexandri T.L.Collins and L. wollumbin T.L.Collins. Results indicated that the narrow endemic C. fulvidum Paul G.Wilson is a variable hybrid between C. newcastlianum (Domin) Paul G.Wilson and C. rupicola (DC.) Paul G. Wilson, and subspecies of C. oxylepis (F.Muell.) Paul G.Wilson to be a polymorphic aggregate or ochlospecies, the subject of ongoing study. We lectotypify H. elatum A.Cunn ex DC. and Helipterum glutinosum Hook. and provide revised descriptions of all taxa in the genera, their conservation status, a dichotomous key, tables distinguishing closely related taxa and distribution maps.

Phytophthora ramorum (Pr) is an invasive oomycete and the causal agent of sudden oak death (SOD) along the coastal fog belt of California and southwestern Oregon and sudden larch death in the UK. The Macaronesian laurel forest (MLF), a relict subtropical evergreen forest of the North Atlantic islands, shares climatic and some taxonomic affinities with those areas affected by SOD. To assess the disease risk, we tested the foliage susceptibility of MLF species and their capacity to sustain Pr sporulation and compared the climatic suitability with other areas where the pathogen is established. Detached leaves of 15 species were inoculated with zoospores and mycelium (through wounding) with five Pr isolates belonging to the EU1 and NA1 clonal lineages. MLF species showed diverse responses to Pr, ranging from extensive necroses on Viburnum tinus to asymptomatic sporulation on Picconia excelsa. Eleven species developed necrotic lesions to different degrees through zoospore inoculation while this increased to 13 species through wound treatment. Overall, small necrotic lesions (i.e. tolerance) were predominant, but Pr was rather aggressive to V. tinus, Arbutus canariensis and Ilex canariensis. Although the mean sporangial production was generally low (25–201 sporangia) in all species, the number of sporangia per leaf in five MLF species was similar to those reported for Umbellularia californica, a key host driving the SOD epidemics in California. Climatic suitability indexes in MLF areas were similar to those where SOD is found in California. Our results indicate a moderate to high risk of Pr establishment if the pathogen is introduced in the MLF.

Although solar-induced chlorophyll fluorescence (SIF) has been proven to be a useful indicator for dynamic drought monitoring, accurately quantifying the trajectory of vegetation SIF change during drought events remains a research challenge. In this case study, we applied a rapid change index (RCI) for the 8-day global ‘Orbiting Carbon Observatory (OCO-2)’ SIF product (GOSIF) to calculate the deviation between GOSIF trajectories and climate norms across China’s Loess Plateau (LP) from 2001 to 2020. We compared the performances of SIF-RCI with GOSIF values and GOSIF anomalies during drought events and evaluated the drought warning potential with the widely used 8-day Standardized Precipitation Evapotranspiration Index (SPEI). Our results showed that SIF-RCI captured the rapid change areas in GOSIF caused by drought and the trajectory of rapid vegetation changes compared to GOSIF values and GOSIF anomalies. The SIF-RCI negative signal accurately identified the onset of drought almost simultaneously with SPEI. The SIF-RCI positive signal also predicted drought recovery with at least 4 8-day periods of lead time. Meteorological factors, especially precipitation, had a great impact on vegetation photosynthesis and this was detected with GOSIF. These impacts varied in different climate zones and vegetation types. Our study contributes to regional drought monitoring and assessment.

The genetic consequences of population isolation include inbreeding, genetic diversity loss and loss of adaptive potential. Koalas across south-western Sydney (New South Wales, Australia) may be vulnerable to isolation due to major roads and cleared forest. A few sites within south-western Sydney are some of the last chlamydia-free sites for koalas. Low genetic diversity and potentially low adaptive potential could lead to local extinction of these chlamydia-free sites. Using reduced representation sequencing, we assessed population differentiation, genetic diversity, relatedness, inbreeding, and gene flow across seven sites in south-western Sydney and the Southern Highlands. We found south-western Sydney koalas had significantly lower diversity, higher relatedness and inbreeding than Southern Highlands koalas. There was no evidence of contemporary gene flow from the more genetically diverse Southern Highlands sites into south-western Sydney. The separation between south-western Sydney and the Southern Highlands likely explains the lower genetic diversity among south-western Sydney sites. It may also explain why chlamydia is yet to reach these sites. However, there is evidence of a disease-front movement of chlamydia from Wingecarribee up into Wollondilly which has high gene flow with Campbelltown, a chlamydia-free site. While gene flow from south to north is low, the risk of chlamydia entering the chlamydia-free sites from a few migrants is notable. With possible low adaptive potential of south-western Sydney sites, a new threat of chlamydia entering the system may lead to population declines in these stronghold areas.

Climate change will have profound and unexpected impacts on biodiversity in the future. These impacts could potentially be mitigated through adaptive and responsive conservation planning, but it remains unclear how adaptation opportunities can be harnessed through careful planning of present‐day activities. Here, we show that the use of flexible conservation strategies that exploit opportunities for climate adaptation can mitigate climate risks without increasing total conservation costs. We estimate the value of allowing flexible delays of conservation investments for protecting habitats of the iconic and threatened koala (Phascolarctos cinereus) in eastern Australia. Conservation strategies that have no option to strategically delay investments face significant trade‐offs between minimizing conservation costs and reducing risks in conservation outcomes. These trade‐offs are substantially mitigated by flexible strategies that strategically delay investments into the future when the effects of climate change are likely to be better understood. Strategic delays are shown to mitigate climate risks in inflexible conservation strategies without even increasing conservation costs. These results show that conservation planning that strategically allocates present‐day conservation resources while also allowing the flexibility to shift these resources in the future is much more likely to achieve cost‐effective conservation outcomes in the face of uncertain climate change impacts.

Biodiversity conservation in agricultural landscapes, the world's predominant land use, could involve sparing, or setting aside, agricultural land from production, implying biodiversity–food trade‐offs. Employing bird species and agricultural data in two panel data sets, we evaluate the extent of set‐aside's trade‐offs in England between 1992 and 2007. Mixed biodiversity outcomes are reflected in a marginal effect, of a 100 ha increase in set‐aside, associated with a 1%–2% increase in species abundance and richness, no impact on Shannon‐Wiener diversity, and a 0.03 standard deviation fall in phylogenetic diversity. Lower phylogenetic diversity indicates that populations of less genetically distinct bird species appear when set‐aside increases. These effects are discontinuous for abundance and richness, and larger in the long run than in the short run for richness and phylogenetic diversity. Set‐aside led, on average, to a 7%–9% fall in cereal land. In turn, this led to an up to 2% decline in cereal output. A yield increase of 5%–10% is likely due to the setting aside of mostly marginal land. Biodiversity–food trade‐offs in agricultural landscapes could be minimized with a carefully targeted set‐aside policy, based on clearly defined biodiversity goals, and in settings where there is still scope for intensification.

Drought remains a menace in the Horn of Africa; as a result, the Ethiopia’s Genale Dawa River Basin is one of the most vulnerable to agricultural drought. Hence, this study integrates remote sensing and machine learning algorithm for early warning identification through assessment and prediction of index-based agricultural drought over the basin. To track the severity of the drought in the basin from 2003 to 2023, a range of high-resolution satellite imagery output indexes were used, including the Vegetation Condition Index (VCI), Thermal Condition Index (TCI), and Vegetation Health Index (VHI). Additionally, the Artificial Neural Network machine learning technique was used to predict agricultural drought VHI for the period of 2028 and 2033. Results depict that during the 2023 period, 25% of severe drought and 18% of extreme drought countered at the lower part of the basin at Dolo ado and Chereti regions. A high TCI value was found that around 23.24% under extreme drought and low precipitation countered in areas of Moyale, Dolo ado, Dolobay, Afder, and Bure lower than 3.57 mm per month. Similarly, increment of severe drought from 24.26% to 24.58% and 16.53% to 16.58% of extreme drought value of VHI might be experienced during the 2028 and 2033 period respectively in the area of Mada Wolabu, Dolo ado, Dodola, Gore, Gidir, and Rayitu. The findings of this study are significantly essential for the institutes located particularly in the basin as they will allow them to adapt drought-coping mechanisms and decision-making easily.

State aid for renewable energy is a crucial element in the transition to a carbon-neutral energy system. However, various State aid schemes in different Member States can also lead to undesirable market distortions and hinder cross-border trade. This is particularly so when one Member State provides production aid, and another Member State has a demand side aid scheme or can result from some Member State providing both State aid and GOs for the same commodity. This undermines the level playing field for all actors within the biomethane markets and leads to subsidy competition, instead of product competition. The article addresses these questions and provides for solutions.

Context Ecosystem assessment using acoustic monitoring technologies can be an efficient method for determining species community composition and breeding activity, but many factors affect the quality of acoustics-data and subsequent level of confidence in derived inferences. Aims We aimed to assess variability in detection probabilities of five frog species using autonomous recording units (ARUs) deployed across a single 1 km² wetland, comprising a lagoon and surrounding area, and subsequently determine the required number of ARUs with 95% confidence in derived presence–absence data. Methods Ten ARUs were deployed in two rings around the lagoon’s centroid close to the water’s edge. Occupancy models were used to derive detection probabilities of species calling in the lagoon from data describing the temporal pattern of calling at each site, which were derived using call recognition software. Key results Only two of the five target species were detected by all 10 ARUs. All target species’ non-zero ARU detection probabilities varied by a factor of 14, and the coefficients of variation in individual ARU detection probability for each species varied by a factor of seven. Simulations revealed seven or eight ARUs are required to achieve 95% confidence in confirming presence of either of the two species with the highest observed detection probabilities, given they are present and calling. Even with ten deployed ARUs, the probability of successful detection of the other three species known to be calling on any day was less than 40%. Conclusions Effective detection was not achieved for all targeted species by several ARUs during a period when hydrology and season suited recruitment activity. Despite all ARUs being deployed at locations favourable for detecting targeted species, stochastic factors drove spatial variability in detection resulting in markedly different data for each ARU and each species. Implications Data describing species presence derived from automated recording units may not be representative due to spatiotemporal variability in detection that varies by species. To improve ARU deployment strategies, a priori knowledge of typical detection probabilities and species spatial variability can be used to determine the required number of call recorders for a set level of confidence.

Environmental DNA (eDNA) analysis has become a popular conservation tool for detecting rare and elusive species. eDNA assays typically target mitochondrial DNA (mtDNA) due to its high copy number per cell and its ability to persist in the environment longer than nuclear DNA. Consequently, the development of eDNA assays has relied on mitochondrial reference sequences available in online databases, or in cases where such data are unavailable, de novo DNA extraction and sequencing of mtDNA. In this study, we designed eDNA primers for the critically endangered Bellinger River turtle (Myuchelys georgesi) using a bioinformatically assembled mitochondrial genome (mitogenome) derived from a reference genome. We confirmed the accuracy of this assembled mitogenome by comparing it to a Sanger‐sequenced mitogenome of the same species, and no base pair mismatches were detected. Using the bioinformatically extracted mitogenome, we designed two 20 bp primers that target a 152‐base‐pair‐long fragment of the cytochrome oxidase 1 (CO1) gene and a 186‐base‐pair‐long fragment of the cytochrome B (CytB) gene. Both primers were successfully validated in silico, in vitro, and in situ.

Riverbank erosion and accretion are currently the most frequently occurring natural disasters along the Nile River, posing socio-economic as well as environmental losses for the neighbouring areas. This study assessed the extent of erosion and accretion along the Sudan-Nile River stretch for three towns, explicitly Dongola, Berber, and Es-Sileit, downstream of the Khartoum confluence. The study utilised Landsat satellite imagery and geospatial techniques to conduct the assessment from 1993 to 2023. Results from the study revealed that Berber demonstrated the highest average rate of erosion and accretion at 60.12 hectares/year and 49.91 hectares/year, respectively, trailed by Es-Sileit. The Dongola site presented the lowest rates of erosion and accretion at 23.25 hectares/year and 32.53 hectares/year, respectively. Erosion was more prominent than accretion in Berber and Es-Sileit, with a net land loss of 316.5 and 198.9 hectares, respectively. Dongola experienced more accretion than erosion, with a net land gain of 287.6 hectares. Additionally, the impacts of erosion and accretion on achieving the Sustainable Development Goals (SDGs) were established, along with several sustainable mitigation actions. This study further identified the synergies between geospatial technological monitoring of erosion and accretion and numerous socio-economic-environmental-allied targets of the SDGs. Therefore, the implementation of geospatial techniques in assessing erosion and accretion would significantly propel sustainable development by identifying zones susceptible to erosion, sediment accumulation, and flooding downstream of the Khartoum confluence, thus promoting practical infrastructural design planning and appropriate community distribution along the Nile Riverbank. Graphical abstract