Modelling environmental DNA transport in rivers reveals highly resolved spatio-temporal biodiversity patterns

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: May 31, 2023

Abstract The ever-increasing threats to riverine ecosystems call for novel approaches highly resolved biodiversity assessments across taxonomic groups and spatio-temporal scales. Recent advances in the joint use of environmental DNA (eDNA) data eDNA transport models rivers (e.g., eDITH) allow uncovering full structure biodiversity, hence elucidating ecosystem processes supporting conservation measures. We applied eDITH a metabarcoding dataset covering three (fish, invertebrates, bacteria) seasons catchment sampled at 73 sites. upscaled eDNA-based predictions approximately 1900 reaches, assessed α - β -diversity patterns over whole network. Genus richness predicted by was generally higher than values from direct analysis. Both varied depending on season group. Predicted fish increased downstream all seasons, while invertebrate bacteria either decreased or were unrelated network position. Spatial mostly downstream, especially bacteria. model yielded more refined assessment freshwater as compared raw data, both terms spatial coverage, diversity effect covariates, thus providing complete picture biodiversity.

Language: Английский

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Bending the curve of global freshwater biodiversity loss: what are the prospects?

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 2, 2024

ABSTRACT Freshwater biodiversity conservation has received substantial attention in the scientific literature and is finally being recognized policy frameworks such as Global Biodiversity Framework its associated targets for 2030. This important progress. Nonetheless, freshwater species continue to be confronted with high levels of imperilment widespread ecosystem degradation. An Emergency Recovery Plan (ERP) proposed 2020 comprises six measures intended “bend curve” loss, if they are widely adopted adequately supported. We review evidence suggesting that combined intensity persistent emerging threats become so serious current projected efforts preserve, protect restore inland‐water ecosystems may insufficient avert losses coming decades. In particular, climate change, complex harmful impacts, will frustrate attempts prevent from already affected by multiple threats. Interactions among these limit recovery populations exacerbate declines resulting local or even global extinctions, especially low‐viability degraded fragmented ecosystems. addition impediments represented we identify several other areas where absolute scarcity fresh water, inadequate information predictive capacity, a failure mitigate anthropogenic stressors, liable set limits on biodiversity. Implementation ERP rapidly at scale through many dispersed actions focused regions intense threat, together an intensification ex‐situ efforts, necessary preserve native during increasingly uncertain climatic future which poorly understood, emergent interacting have more influential. But implementation must accompanied improve energy food security humans – without further compromising condition Unfortunately, political policies arrest environmental challenges change do not inspire confidence about possible success ERP. parts world, Anthropocene seems certain include extended periods uncontaminated surface runoff inevitably appropriated humans. Unless there step‐change societal awareness commitment biodiversity, established methods protecting bend curve enough continued degradation loss.

Language: Английский

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Small dams fragment assemblages of diadromous and freshwater decapods in Hong Kong lowland streams

Hydrobiologia, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 10, 2025

Language: Английский

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Current extinction rate in European freshwater gastropods greatly exceeds that of the late Cretaceous mass extinction

Communications Earth & Environment, Journal Year: 2021, Volume and Issue: 2(1)

Published: May 21, 2021

Abstract The Cretaceous–Paleogene mass extinction event 66 million years ago eradicated three quarters of marine and terrestrial species globally. However, previous studies based on vertebrates suggest that freshwater biota were much less affected. Here we assemble a time series European gastropod occurrences inferred rates covering the past 200 years. We find increased by more than one order magnitude during extinction, which resulted in 92.5% all species. phase lasted 5.4 was followed recovery period 6.9 present gastropods are orders higher even these revised estimates for extinction. Our results indicate that, unless substantial conservation effort is directed to ecosystems, crisis will have severe impact millions come.

Language: Английский

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Quantifying the ecological impacts of alien aquatic macrophytes: A global meta‐analysis of effects on fish, macroinvertebrate and macrophyte assemblages

Freshwater Biology, Journal Year: 2022, Volume and Issue: 67(11), P. 1847 - 1860

Published: Aug. 30, 2022

Abstract Biological invasions constitute a pervasive and growing threat to the biodiversity functioning of freshwater ecosystems. Macrophytes are key primary producers ecosystem engineers in freshwaters, meaning that alien macrophyte have capacity alter structure function recipient aquatic ecosystems profoundly. Although prevailing wisdom holds tend compromise function, ecological impacts invasion not been quantitatively reviewed date. Here we present global meta‐analysis 202 cases from 53 research articles, exploring on abundance diversity three ubiquitous ecologically important focal groups, which together comprise bulk non‐microbial biodiversity: resident macrophytes, macroinvertebrates fish. Our synthesis includes data all continents except Antarctica Asia, covering 25 species, but reveals considerable taxonomic geographical biases knowledge. Meta‐analysis results reveal by macrophytes has an overall negative impact no consistent effect abundance. At finer resolution, detect strong diversity, significant smaller positive submerged macroinvertebrates. Effects fish appear inconsistent. findings emphasise importance context‐ taxon‐specific informing appropriate proportionate management invasions, since consistently negative. We also identify limitations existing studies, quantitative being lacking for many taxa.

Language: Английский

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The role of connectivity in conservation planning for species with obligatory interactions: Prospects for future climate scenarios

Global Change Biology, Journal Year: 2024, Volume and Issue: 30(2)

Published: Feb. 1, 2024

Abstract Climate change may lead to range shifts, and barriers such displacements result in extirpations from previously suitable habitats. This be particularly important freshwater ecosystems that are highly fragmented by anthropogenic obstacles, as dams other smaller in‐stream barriers. Conservation planning freshwaters should consider the dynamic effects of climate ability species cope with it. In this study, we developed a framework for incorporating climate‐driven dispersal into conservation taking account medium long‐term impacts obligatory interactions. Given mussels (Bivalvia: Unionida) group threatened organisms dependent on fish hosts complete their larval development dispersal, used Marxan prioritize areas joint Iberian Peninsula case study. We tested two connectivity scenarios between current future habitats, (i) unlimited capacity (ii) constrained artificial barriers, also identified priority translocation were unable disperse. Accounting distributions allowed identification areas, but disregarding unrealistic solutions. Integrating location more likely colonized following climatic although resulted an additional loss six eight features (~5%–7%) compared solutions without constraints. Between 173 357 (~1.6%–3.3%) will potentially block irreplaceable units. Where removal is unfeasible, translocations additionally cover up do not meet targets due study highlights challenge identifying protected safeguard biodiversity under change.

Language: Английский

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High spatial variability in a species‐rich assemblage of diadromous fishes in Hong Kong, southern China

Journal of Fish Biology, Journal Year: 2024, Volume and Issue: 105(3), P. 663 - 681

Published: June 3, 2024

China has experienced substantial coastal reclamation and damming of rivers. These changes have the potential to impact migrations diadromous fishes between sea fresh waters, but composition these impacts barriers their movement in received little attention. We inventoried species distribution fishes, on them, Hong Kong Special Administrative Region (HKSAR), southern China. Fish assemblages were surveyed using hand-nets, supplemented by cast-netting single-pass snorkel surveys, 24 small streams across three regions. Surveys undertaken multiple occasions during wet dry seasons account for monsoonal tropical climate. Twenty-eight collected, mostly gobies, amounting over half (53%) total richness primary freshwater fishes; four additional are known from literature records. Diadromous was 48% greater season, when all encountered. Richness varied substantially among streams, a maximum 17 (2 that diversity hot spots) none (3 streams). The most widespread fish Glossogobius giuris (71% frequency occurrence), followed Mugil cephalus (58% occurrence) Eleotris oxycephala (50% occurrence). remaining 25 occurred fewer than streams; 12 confined single stream may be locally threatened. There conspicuous spatial differences HKSAR, despite its limited extent (1114 km

Language: Английский

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The critical role of natural history museums in advancing eDNA for biodiversity studies: a case study with Amazonian fishes

Scientific Reports, Journal Year: 2021, Volume and Issue: 11(1)

Published: Sept. 13, 2021

Ichthyological surveys have traditionally been conducted using whole-specimen, capture-based sampling with varied but conventional fishing gear. Recently, environmental DNA (eDNA) metabarcoding has emerged as a complementary, and possible alternative, approach to whole-specimen methodologies. In the tropics, where much of diversity remains undescribed, vast reaches continue unexplored, anthropogenic activities are constant threats; there few eDNA attempts for ichthyological inventories. We tested discriminatory power MiFish primers existing public reference libraries compared this methods in two distinct ecosystems megadiverse Amazon basin. our study, provided an accurate snapshot fishes at higher taxonomic levels corroborated its effectiveness detect specialized fish assemblages. Some flaws studies routine issues addressed natural history museums. Thus, by expanding their archives adopting series initiatives linking collection-based research, training outreach, museums can enable effective use survey Earth's hotspots biodiversity before taxa go extinct. Our project surveying poorly explored rivers vouchered build Neotropical serve model protocol.

Language: Английский

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A review of conservation status of freshwater fish diversity in China

Journal of Fish Biology, Journal Year: 2023, Volume and Issue: 104(2), P. 345 - 364

Published: Nov. 6, 2023

China harbors a high species diversity of freshwater fishes not shared with any its neighboring nations. Freshwater fish in the country has been under severe threat from human activities over past decades, thus conservation and ecosystems is urgently needed. To accumulate baseline data for guiding protection actions, third red list assessment Chinese was carried out. Among assessed, there are 355 at-risk (22.3% total), including 69 ranked as Critically Endangered, 97 189 Vulnerable. Two classified Extinct one Regionally Extinct. China's level seems to be lower than known average found IUCN's global fishes, but this an artifact rate Data Deficient. Conservation presently facing grim situation China. Imperilment primarily attributed habitat loss degradation arising perturbations, particularly river damming. Despite adoption protected areas setting up, captive breeding release, fishing moratorium, efforts compromised by disproportional attention biodiversity conservation, deficiency, insufficiently designed networks, inefficient or inadequate implementation strategies. achieve objectives it proposed conduct national-scale survey reassess their status, develop systematic planning ecosystems, prioritize strategies development, perform genetic-based releasing concert other implement flexible moratorium different water bodies.

Language: Английский

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Evaluation of primer pairs for eDNA‐based assessment of Ephemeroptera, Plecoptera, and Trichoptera across a biogeographically diverse region

Environmental DNA, Journal Year: 2022, Volume and Issue: 4(6), P. 1356 - 1368

Published: Aug. 8, 2022

Abstract Macroinvertebrates serve as key indicators in ecological assessments of aquatic ecosystems, where the composition and richness their communities are indicative environmental anthropogenic change. Established monitoring macroinvertebrates is expensive time‐consuming, relies on expert taxonomic knowledge. In contrast, biomonitoring based molecular tools can support faster characterization but needs validation for target groups study region. Here, we used data from a program covering large biogeographic gradient to compare routine kick‐net method with eDNA metabarcoding. We two primer pairs targeting COI, one broad metazoan spectrum (mICOIintF/jgHCO2198) another more recently developed pair optimized detection freshwater invertebrates (fwhF2/EPTDr2n). macroinvertebrate focus orders Ephemeroptera, Plecoptera, Trichoptera across 92 rivers Switzerland, four continental drainage basins an elevational range 198 1650 m a.s.l. Across all sample sites, detected distinct taxa than either metabarcoding approaches. At site level, however, both average species. Comparing pairs, fwhF2/EPTDr2n captured species assigned indicator Trichoptera, showed significantly larger overlap method. However, community still varied among different Fewer were recovered by eDNA, whereas Plecopterans other This highlights importance optimization novel approaches under consideration organismal group area.

Language: Английский

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