Aquatic publication review (6)

With the global increase in human pressure on Earth’s systems, it’s hardly surprising that many scientific articles are alarmist in nature. The current literature review could not miss such. We begin with a report on species threatened with extinction in Europe. The statistics are decidedly pessimistic. Ecosystems and their components will require increasing involvement in the protection or restoration of their diversity, functions and services provided to humans, including the development of appropriate legislative solutions (e.g., the issue of springs, which currently lack systematic legal protection) or the involvement of community groups (e.g., using the knowledge and experience of recreational fishermen through citizen science to more effectively protect ichthyofauna). It is also necessary to improve monitoring tools using modern techniques such as image information and modeling. The review also included more publications on freshwater salinity.

1. a multi-taxon analysis of European Red Lists reveals major threats to biodiversity

Hochkirch A., Bilz M., Ferreira C.C., et al, (2023). A multi-taxon analysis of European Red Lists reveals major threats to biodiversity. PLoS ONE, 18, 11, e0293083.

One of the major global problems facing our planet is the widely observed decline in biodiversity, and the number of species threatened with extinction continues to rise. Countering this trend requires, first and foremost, a proper understanding of the phenomenon, its scale, causes and ways to curb it. This task was undertaken by a team of dozens of scientists from various European countries, led by Axel Hochkirch of the Musée National d’Histoire Naturelle in Luxembourg. Based on the IUCN (International Union for Conservation of Nature) Red List of Threatened Species, the researchers analyzed the conservation status of nearly 14,700. European terrestrial, freshwater and marine species (about 10 percent of the continental biota), including all vertebrates and selected groups of invertebrates and plants. Their results, published in early November in the journal PLoS ONE, show that nearly _one-fifth of European species face extinction, with the risk of extinction higher for plants (27 percent) and invertebrates (24 percent) than vertebrates (18 percent). In terms of aquatic species, the authors stress that the threat status of many indicator taxa for inland waters (e.g., mayflies Ephemeroptera, forkbeards Plecoptera and caddisflies Trichoptera) or marine species (e.g., marine crustaceans and mollusks) is still inadequately recognized. The authors point to changes in land use, including agricultural practices and associated habitat loss, overexploitation of biological resources, pollution, and urban infrastructure development as the main threats to biodiversity. Key actions to curb further biodiversity decline are maintaining and restoring sustainable land and water use practices.

2. Mediterranean springs: Keystone ecosystems and biodiversity refugia threatened by global change. Global Change Biology

Fernández-Martínez M., Barquín J., Bonada N., et al, (2023). Mediterranean springs: Keystone ecosystems and biodiversity refugia threatened by global change. Global Change Biology, 00, e16997.

Spring ecosystems are one of the most important, but still insufficiently studied habitats for specific aquatic and wetland biota. They develop at the interface between surface and groundwater, create conditions for unique assemblages of organisms (including a large group of endemic species), perform important ecological functions and provide ecosystem services. These ecosystems were looked at by a team of scientists from Spain, Portugal and Italy, who published the results of the review in Global Change Biology. The authors provide a synthesis of the main features of the structure and functioning of Mediterranean headwaters, describe their ecological values and biodiversity patterns, and analyze the main threats they face. Climate change, resulting in perturbed patterns of temperature, evapotranspiration and precipitation, can modify the water balance and chemical composition of spring waters. Researchers’ studies indicate that 45 percent of springs in the Catalonia mountain range, surveyed in 2013, have completely disappeared over a decade due to desiccation, and the flow has decreased by 92 percent. Also, eutrophication caused by agricultural practices, wastewater discharges and new pollutants such as pharmaceuticals, personal care products and pesticides are of increasing concern in terms of preserving the biodiversity of these ecosystems.

Laws protecting spring ecosystems are poor and inadequate. The EU Habitats Directive includes only limestone springs with Cratoneurion commutati communities in its list of protected habitats, meaning that other spring ecosystems are left to their own devices. Indirect protection can be given to them by protecting, for example, alkaline bogs and other wetlands, as these habitats often have springs in their structure. However, the preservation of spring ecosystems urgently requires the provision of comprehensive legislation.

Admittedly, the article refers to the Mediterranean region, but Poland also has these valuable ecosystems, which are subject to similar pressures and deserve to be protected from modern threats.

3. Exploring ecological knowledge in recreational fishing for conservation purposes: A literature review. Global Ecology and Conservation

Löki V., Nagy J., Neményi Z., et al, (2023). Exploring ecological knowledge in recreational fishing for conservation purposes: A literature review. Global Ecology and Conservation, 48, e02697.

We have known for a long time that the practical knowledge available to water users can contribute to proper water management and protection. A recent issue of Global Ecology and Conservation published a review article by a team of scientists from Hungary on the potential of using the knowledge of recreational fishermen (anglers) to improve ichthyofauna conservation. Recreational fishing is a very popular activity that provides an opportunity for non-specialists to collect reliable ecological data. Knowledgeable anglers can significantly improve our understanding of nature and prioritize conservation tasks appropriately. Based on an analysis of 81 publications, carefully selected from several thousand papers, the authors presented and evaluated the state of recreational fishermen’s ecological knowledge, their perception of nature and their contribution to conservation. The results indicate that mapping the knowledge of recreational fishermen provides an opportunity to better understand the functioning of aquatic habitats and wetlands. The observations and insights of this user group can provide essential data for species conservation and habitat management, and can help develop citizen science projects on marine and freshwater ecosystems around the world.

The article is part of the so-called “citizenscience” movement gaining popularity today, which promotes the inclusion of volunteer groups in research and the use of their knowledge and experience to expand scientific knowledge.

4 Identification of a pharyngeal mucosal lymphoid organ in zebrafish and other teleosts: Tonsils in fish?

Resseguier J., Nguyen-Chi M., Wohlmann J., et al, (2023). Identification of a pharyngeal mucosal lymphoid organ in zebrafish and other teleosts: Tonsils in fish? Science Advances, 9, 44.

While we’re on the subject of fish, it’s worth mentioning a paper just published in Science Advances that sheds new light on the anatomy and physiology of these animals. It turns out that sophisticated immune systems are not a characteristic only of mammals. In Evolutionary Biology, researchers report the discovery in fish of an organ that can perform immune functions comparable to mammalian tonsils. Using a T lymphocyte/NK cell marker (ZAP70) and advanced imaging techniques, the researchers examined the lymphoid architecture of the gill cavity of the striped danios and identified a hypopharyngeal structure whose cellular structure and function prove that it is a secondary lymphoid organ. They named their find the Nemausean lymphoid organ (NELO, or Nemausean lymphoid organ) after a mythological figure associated with healing and water. In response to infection, NELO shows structural changes – it forms clusters of T/NK cells. NELO’s lymphoid tissue and gills combine to form a cohesive unit within the large mucosal lymphatic network. The structure has been identified in many fish species. It appears that sublime immune systems are not a trait exclusive to mammals.

5. Freshwater salinization syndrome limits management efforts to improve water quality. Front. Environ

Maas C.M., Kaushal S.S., Rippy M.A., et al,(2023). Freshwater salinization syndrome limits management efforts to improve water quality. Front. Environ. Sci. 11:1106581.

6. Freshwater Salinization Syndrome Alters Nitrogen Transport in Urban Watersheds

Galella J.G., Kaushal S.S., Mayer P.M., et al. (2023) Freshwater Salinization Syndrome Alters Nitrogen Transport in Urban Watersheds. Water, 15, 3956.

This fall, two more papers on the enduring problem of anthropogenic salinity in inland waters were published a few weeks apart. In the context of the NIK report on this problem in the Oder River, published in mid-November, Water Matters readers may find it an interesting voice in the worldwide discussion.

The first article appeared in Frontiers in Environmental Sciences and dealt with freshwater salinisation syndrome (syndrome), which we have written about on several occasions. “freshwater salinisation syndrome”, which we have written about more than once in “Water Matters“). This syndrome comprises a group of biological, physical and chemical interactions observed in freshwater ecosystems in response to excessive salinity. Using six urban drainage basins of the Chesapeake Bay, US, as an example, the researchers examined the temporal and spatial distribution of chemical mixtures (called “chemical cocktails” by the authors) along streams with varying degrees of drainage and riparian forest protection, as well as their dilution potential, including reducing salt ion concentrations, among others. On the path of flow through protected areas. The authors point to the use of road salt as an important source for enriching urban chemical cocktails with salt ions and metals (such as Na+, Mn and Cu). In contrast, the dilution efficiency of these pollutants along streams was significantly correlated with the width of the riparian forest buffer, the type of salt and the distance from the pollution source.

The second paper, published in the journal Water, by partly the same team of authors, in turn analyzes the problem of the effect of freshwater salinity on the balance and circulation of nitrogen forms (total dissolved nitrogen TDN and nitrate _{NO3-/nitriteNO2-}) using five urban watercourses of the Baltimore-Washington DC metropolitan area in the Chesapeake Bay region, USA, as an example. The researchers observed statistically significant positive relationships between the parameters analyzed, confirming a previously demonstrated relationship: freshwater salinity can alter the magnitude and distribution of total dissolved nitrogen delivered to recycled waters during the winter months following road salt application. This relationship was present at all sites, regardless of land use, suggesting that mass transport of Cl- and _NO3-/NO2- is influenced by similar factors such as soil ion exchange, evaporation, soil sodium dispersion, hydrological leaching and biogeochemical processes. The authors also stress that the EPA’s (for the United States) chloride concentration criteria of 230 mg Cl/l for chronic toxicity and 860 mg Cl/l for acute toxicity are too high to prevent disruption of zooplankton communities and, consequently, the entire trophic network. Polish scientists have come to similar conclusions, proving in the pages ofAquatic Sciencesthe negative impact of road salt use on zooplankton communities in the city’s reservoirs of Lodz.

6. remote sensing-enabled machine learning for river water quality modeling under multidimensional uncertainty

Rahat S.H., Steissberg T., Chang W. et al. (2023). Remote sensing-enabled machine learning for river water quality modeling under multidimensional uncertainty. Science Of The Total Environment, 898, 165504.

Effective water conservation requires the development of increasingly sophisticated modes of operation. Growing databases and awareness of the complexity of the determinants of river water quality are stimulating the development of new equipment, techniques and tools, both measurement and statistical. In the pages of the journal STOTEN, a team of U.S. researchers proposes a new method for supporting traditional ground-based observations with remote sensing data and using a machine learning model to account for the multidimensionality of impacts on river water quality. As a model parameter, the authors used total suspended solids (TSS), which can serve as a surrogate for chemical and biological pollutants. This paper presents a method for diagnosing river pollution by using a Long Short-Term Memory Network(LSTM) neural network model trained on data acquired from satellite reflections from a Moderate Resolution Imaging Spectroradiometer (MODIS, The Moderate Resolution Imaging Spectroradiometer. Moderate Resolution Imaging Spectroradiometer), calibrated on TSS data collected by traditional methods. The reliability of the model, as assessed by standard statistical parameters, was satisfactory for most of the stations analyzed.

The work is another example of the potential of using image information and machine learning methods to effectively predict water quality in complex river systems under uncertain climatic conditions.