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Rivers are crucial ecosystems supporting biodiversity and human well‐being, yet they face increasing degradation globally. Traditional river biomonitoring methods based on morphological identification of macroinvertebrates present challenges in terms of taxonomic resolution and scalability. This study explores the application of DNA metabarcoding analysis in both bulk and environmental DNA (eDNA) samples for comprehensive assessment of macrozoobenthic biodiversity, detection of invasive and endangered species, and evaluation of river ecological status in northwestern Spain. DNA metabarcoding of homogenized bulk samples and water eDNA revealed a mean of 100 and 87 macrozoobenthos species per sample respectively. However, the specific composition was significantly different with only 27.3% of the total species being shared. It was not possible to identify all the OTUs to species level; only 17.43% and 49.4% of the OTUs generated could be identified to species level in the bulk and eDNA samples, respectively. Additionally, a total of 11 exotic species (two first records for the Iberian Peninsula and another three first records for Asturias region) and one endangered species were detected by molecular tools. Molecular methods showed significant correlations with morphological identification for EQR values (Ecological Quality Ratio) of IBMWP index, yet differences in inferred river ecological status were noted, with bulk samples tending to indicate higher status. Overall, DNA metabarcoding offers a promising approach for river biomonitoring, providing insights into biodiversity, invasive species, and ecological status within a single analysis. Further optimization and intercalibration are required for its implementation in routine biomonitoring programmes, but its scalability and multi‐tasking capabilities position it as a valuable tool for integrated monitoring of river ecosystems. [ABSTRACT FROM AUTHOR]

Floodplains are crucial components of river landscape, essential for the biodiversity and ecological integrity of large rivers. However, they are often overlooked and underestimated when assessing the ecological status of the main river channel.The main objective of this study was to identify the most relevant scheme for assessing the ecological status of side arms in the Danube floodplain (Slovakia) based on benthic invertebrates.The calculation of ecological status for the Danube main channel was adapted to the environmental conditions of the floodplain as a measure of the evaluation accuracy of six taxonomically different floodplain indexes. The study was based on a comprehensive survey of benthic invertebrate diversity conducted at 19 sampling sites, covering eupotamal and parapotamal side arms.Three floodplain indexes that significantly correlated with ecological status were categorised based on predicted values in relation to status class thresholds. The floodplain index based on Polychaeta, Oligochaeta, Mysida, Isopoda and Amphipoda (FI_P) showed the best result, aligning closely with the commonly used classification of lateral habitats. Although it divides the eupotamon into two subclasses, a main channel and a side arm, the inclusion of two different eupotamal habitats in the classification supports the geomorphological variability of side arms and their degree of ecological succession.The shortcomings of the assessment based on the lateral habitat classification scheme are discussed, emphasising the importance of applying this method for the assessment of floodplain waters and their conservation management. [ABSTRACT FROM AUTHOR]

Large watercourses are characterised by significant spatial and temporal changes in water quality due to both natural and anthropogenic impacts. The paper analyses changes in the Danube's spatial and seasonal water quality in its middle part at five monitoring stations for the period 2018–2022. Examined water quality parameters include oxygen saturation (Os), ammonium (N-NH4), pH, 5-day biochemical oxygen demand (BOD), nitrate nitrogen (N-NO3), orthophosphates (P-PO4), suspended solids (SS), electrical conductivity (EC), and water temperature (WT). Furthermore, the analysis took into account the influence of two additional factors: air temperature (AT) and discharge (D). Throughout the entire period under study, all parameters were characterised by low concentration values, which met the environmental objective of good ecological status. The use of multivariate statistical methods allowed for the identification of EC, N-NH4, WT, Os, SS, and N-NO3 as determining the greatest spatio-seasonal variability of water quality in a selected section of the Danube. Regression models determined WT, EC and nitrogen nitrate changes as depending on AT, flow, and exposure time. Knowing models not only gives a better understanding of the dynamics of changes in water quality in the stretch of the Danube under study but potentially allows the prediction of these parameters based on easily measurable environmental variables. [ABSTRACT FROM AUTHOR]

Deserts are unique ecosystems that provides suitable habitats to many floral and faunal species and that are beneficial to human beings in many ways. Desert ecosystems are affected by several natural and anthropogenic factors, resulting in the degradation of ecosystem goods and services provided by them. Thus, there is a need to monitor them. Accordingly, the ecological status of 34 major non-polar deserts of the world have been monitored for a period of four decades. We have used (i) vegetation cover and NDVI (vegetation density/vigour) as indicators of ecological conditions, and (ii), long term rainfall and temperature patterns to monitor the extent and the effect of climatic variations. Among the 34 deserts, Taklimakan has consistently the lowest NDVI, while Tanami has the highest NDVI during the entire monitoring period. The Asian Kavir and Kharan deserts have the lowest vegetation cover; Tanami has the highest vegetation cover. Out of 34 deserts, Gobi, Kalahari, Margo, Mu Us, Simpson, Strzelecki, Taklimakan and Thar deserts have shown an increasing trend in vegetation cover. While, Chalbi, Patagonian and Sonoran deserts have shown a decreasing trend. Thar, Sechura and Sahara have shown an increasing trend in precipitation, while Namib has shown an opposite trend. 31 deserts have shown an increasing trend in the temperature. Present study is important as changes in the ecological conditions of the deserts have a profound impact on the land surface albedo, surface energy balance, regional climate, carbon sequestration, biodiversity, and global dust emissions. [ABSTRACT FROM AUTHOR]

Wastewater treatment plant (WWTP) effluents can be sources of environmental contamination. In this study, we aimed to understand whether effluents of three different WWTPs may have ecological effects in riverine recipient ecosystems. To achieve this, we assessed benthic phytobenthos and macroinvertebrate communities at three different locations relative to the effluent discharge: immediately upstream, immediately downstream and 500-m downstream the effluent discharge. Two approaches were employed: the ecological status classification as defined in the Water Framework Directive (WFD) based on biological indicators; constrained multivariate analysis to disentangle the environmental drivers (physicochemical variables and contaminants, namely metals, polycyclic aromatic hydrocarbons, pharmaceuticals, and personal care products) of ecological changes across the study sites. The results showed inconsistencies between the WFD approach and the multivariate approach, as well as between the responses of macroinvertebrates and diatoms. The WWTP effluents impacted benthic communities in a single case: macroinvertebrates were negatively affected by one of the WWTP effluents, likely by the transported pharmaceuticals (other stressors are essentially homogeneous among sites). Given the findings and the scarcity of consistent evidence on ecological impacts that WWTP effluents may have in recipient ecosystems, further research is needed towards more sustainable regulation and linked environmental protection measures. [ABSTRACT FROM AUTHOR]

In the twenty-first century, numerous forms of pollution have adversely impacted freshwater and the entire aquatic ecosystem. The higher population density in urban areas also contributes to increased releases of substances and thermal contaminants, significantly stressing the ecosystem of industrial companies. This study aimed to assess the potential pressure of industrial and municipal activities on water quality, radioactivity levels, and biological diversity, focusing on the consequences of radionuclides on periphytic diatom communities. Furthermore, the environmental impact of pollutants will be evaluated to monitor the ecological condition of the Ismailia Canal. Chemical analyses employed various instruments and methods to identify and quantify matter, with radionuclide elements measured by gamma spectrometry and diatoms counted and identified by inverted microscopy. Our results revealed that the canal was classified as excellent for irrigation, aquatic life, and drinking water based on FAO, CCME, and EWQS water quality indices, with high nutrient levels at Abu Za'baal fertilizer company. The activity concentration of 226Ra-series, 232Th-series, and 40K in the water and sediment samples for two seasons was within the guideline values, except for a few stations in the zone [B] (the industrial zone). Fertilizer samples (raw material) showed a high value of the 226Ra-series activity. Diatom community structure significantly varied across the different canal locations regarding the presence or absence of industrial activities, with no discernible variations between the study seasons. A specific variety of algal species was found to be predominant at the highest radioactive sites. Redundancy analysis (RDA) showed a significant correlation between parameters (pH, Na, TDS, PO4, SO4, SiO2, K, and CO3), radionuclides, environmental conditions, and the composition of the diatom community, especially in the area affected by industrial discharges. Moreover, the radiological hazard index in water and sediment remained below the maximum for two seasons. This research provides valuable data and information for communities and decision-makers, suggesting the strategic use of phycoremediation as a water biotreatment process to protect the valuable economic resources of the Ismailia Canal. [ABSTRACT FROM AUTHOR]

With the rapid growth and development of urban areas, the economy has often been prioritized at the expense of the environment and ecological systems. However, it is essential to delve deeper into the relationship between the economy and the ecological environment. Therefore, this study introduces a comprehensive evaluation system that encompasses economic, ecological, and environmental factors in the Beijing–Tianjin–Hebei urban agglomeration in China. The Criteria Importance Through Inter-criteria Correlation (CRITIC) method is utilized to determine the weights of various indicators, and coupling as well as coupling coordination models are employed to investigate the spatiotemporal trends and interrelationships of the three factors. The results indicate that the economic development index has displayed a consistent uptrend since 2000, with the economic development index from 2015–2020 increasing by approximately four times compared to 2000–2005. The ecological status index has also increased in the last five years, with a rise of about 0.05 from 2015–2020 compared to 2000–2005. The environmental status index has fluctuated but generally increased, with a rise of approximately 5.6 times from 2015–2020 compared to 2000–2005. The coupling degree of the Beijing–Tianjin–Hebei urban agglomeration is relatively high, with intense coupling from 2005–2020, and moderate coupling from 2000–2005. Furthermore, the coupling coordination has continuously improved from mild maladjustment to barely coordinated from 2000 to 2020, indicating the enhancement of the coupling coordination of the three factors. It is crucial to acknowledge that there exists spatial heterogeneity in both the coupling degree and coupling coordination degree. This heterogeneity stems from the uneven progress in economic development, ecological conditions, and environmental status across various cities. Additional endeavors are required to foster the harmonized advancement of these factors across the entire region. [ABSTRACT FROM AUTHOR]

Catchment land use/land cover (LU/LC) is one of the crucial determinants of the water quality and condition of biota in aquatic environments. The aim of this study was to investigate how LU/LC in lake catchments influences the physicochemical and biological indicators used to assess the ecological status of lakes in Poland and whether these relationships vary depending on the spatial range. We analysed the catchment LU/LC forms of 114 flow-through lakes in three spatial ranges, i.e., a 100 m-wide buffer strip (BUF100), the direct catchment (DIR), and the total catchment (TOT). The water quality and biological variables were derived from the state monitoring conducted in the period 2012–2013. The redundancy analyses (RDA) and the Monte Carlo permutation tests depicted that the strength in explaining the parameter followed the order: TOT > DIR > BUF100 for physicochemical parameters, DIR = TOT > BUF100 for phytoplankton indicators and BUF100 > DIR > TOT for macrophyte indicators. In the direct and total catchment, the proportion of arable lands was decisive in shaping the macrophyte and physicochemical status, while the proportion of artificial surfaces affected phytoplankton status. It was also found that forested buffer zones promoted good macrophyte ecological status. The other types of LU/LC, i.e., meadows and pastures, wetlands, and surface waters exhibited little to no or marginal impact on the physicochemical and biological indicators, regardless of the spatial scale considered. Our results contribute to the rational planning of land development in lake surroundings, including the design of protected areas for inland waters. [ABSTRACT FROM AUTHOR]

Abstract Rivers are crucial ecosystems supporting biodiversity and human well‐being, yet they face increasing degradation globally. Traditional river biomonitoring methods based on morphological identification of macroinvertebrates present challenges in terms of taxonomic resolution and scalability. This study explores the application of DNA metabarcoding analysis in both bulk and environmental DNA (eDNA) samples for comprehensive assessment of macrozoobenthic biodiversity, detection of invasive and endangered species, and evaluation of river ecological status in northwestern Spain. DNA metabarcoding of homogenized bulk samples and water eDNA revealed a mean of 100 and 87 macrozoobenthos species per sample respectively. However, the specific composition was significantly different with only 27.3% of the total species being shared. It was not possible to identify all the OTUs to species level; only 17.43% and 49.4% of the OTUs generated could be identified to species level in the bulk and eDNA samples, respectively. Additionally, a total of 11 exotic species (two first records for the Iberian Peninsula and another three first records for Asturias region) and one endangered species were detected by molecular tools. Molecular methods showed significant correlations with morphological identification for EQR values (Ecological Quality Ratio) of IBMWP index, yet differences in inferred river ecological status were noted, with bulk samples tending to indicate higher status. Overall, DNA metabarcoding offers a promising approach for river biomonitoring, providing insights into biodiversity, invasive species, and ecological status within a single analysis. Further optimization and intercalibration are required for its implementation in routine biomonitoring programmes, but its scalability and multi‐tasking capabilities position it as a valuable tool for integrated monitoring of river ecosystems.

In many EU countries, a large proportion of domestic effluents is treated in small, decentralized wastewater treatment plants (WWTPs) which often lack appropriate treatment technologies. The low efficiency of these systems and their incorrect maintenance often contribute to environmental deterioration, with a large quantity of inadequately treated sewage dispersed in the soil or discharged into superficial watercourses. In the Abruzzo region (Central Italy), almost all rivers and streams receive wastewater from Imhoff tanks with only primary treatments. The ecological impacts of these effluents have rarely been investigated. This paper aimed to evaluate the response of freshwater invertebrates to Imhoff effluents in receiving watercourses with different ecological status. Our results showed that wastewater from Imhoff plants negatively affected the structure and composition of freshwater communities, with a reduction in the richness and abundance of more sensitive taxa and an increase in the most tolerant ones. These negative effects were more accentuated during low flow periods and in streams with moderate ecological status. To improve the ecological status of rivers and streams and to limit the diffusion of pathogens and micropollutants in freshwater, a more efficient (secondary treatments, possibly with nature-based solutions) and sustainable (water reuse or sewage sludge recycling) approach to wastewater treatment in decentralized WWTPs is urgently needed. [ABSTRACT FROM AUTHOR]

Here, we studied the influence of changes of aquatic phases (standing and flowing phases) and human-induced habitat variability (natural and artificial) on the composition and diversity of benthic diatom assemblages in a small lowland stream in the Pannonian Ecoregion. Significant differences in composition were hypothesized between phases and habitats. Lower diversity was hypothesized in the flowing phase and in the artificial habitat. In addition, worser ecological status were assumed in the artificial habitat and in the standing phase than in the others. Our results only partially supported our hypotheses. While there was no significant difference in the composition of the assemblages between the natural and concreted habitats, the alteration in flow conditions resulted in a significant change. No significant differences in diversity were found between aquatic phases. In contrast, biodiversity was higher in the artificial habitat than in the natural one. While the anthropogenic impact, i.e., concreted streambed has no significant influence on diatom-based ecological status, values of diatom indices were significantly higher in the flowing phase. Our results highlight that extreme weather events play a major role in shaping diatom assemblages even during a short period, which should be taken into account in water management and nature conservation measures. [ABSTRACT FROM AUTHOR]

Aquatic vegetation is a reliable indicator of the ecological condition of surface waters. Abundance, composition and spatial structure of aquatic communities are shaped by an array of factors, which include both natural abiotic features of an ecosystem and external influences. We investigated whether the physical features, i.e., wind exposure and slope of the lake basin, have a significant impact on the taxonomic composition and spatial structure of macrophyte communities from non-impacted, highly alkaline, lowland lakes of the European plains (Poland). We further examined whether these features can affect the classification of the ecological status of lakes assessed in accordance with the Water Framework Directive requirements. Morphological, botanical and physicochemical data from 260 transects in 16 non-disturbed lakes of Polish lowlands surveyed in the years 2011-2016 were analysed. For each transect, littoral slope and wind exposure were calculated. Additionally, the total phosphorus concentration was used as a proxy of water trophy. The relationships between environmental variables and macrophyte indices as well as the syntaxonomic composition of aquatic and rush vegetation (dependent variables) were analysed using multidimensional ordination techniques (redundancy analysis, variation partitioning and indicator values), correlation and regression analysis. Among the three analysed environmental factors (littoral slope, wind exposure and water trophy), in almost all cases the latter explained the highest variance in the macrophyte community, while the contribution of the first two was at most moderate, weak or usually statistically insignificant. However, lakes with steeper slopes were more frequently inhabited by stoneworts and had better ecological status than those with a gentle littoral shape. This may be attributed to the links between lake morphometry and rate of eutrophication, with deep lakes supporting more effective dilution of substances. Furthermore, lower light requirements of charophytes than of higher plants and the capacity to growth in unstable sediments facilitate charophyte establishment in deeper and steeper parts of the littoral over higher plants. Our findings suggest that in lowland lakes with relatively small areas, moderate depths and low wind exposure typical of European plains, slopes and weaving do not hamper vegetation development and do not negatively affect the macrophyte assessment of ecological status. In such ecosystems, eutrophication seems to be a more important factor determining aquatic vegetation than physical features. [ABSTRACT FROM AUTHOR]

The European Fish Index EFI+ is the only fish-based multimetric index for the assessment of the ecological status of running waters that is validated and thus applicable across most countries of the European Union. Metrics of the index rely on several attributes of the species present in the fish assemblage, irrespective of their native/alien status. The abundance of alien fish, together with other anthropogenic impacts, is one of the most important threats to the conservation of native fish and ecosystem health and is also an indicator of degraded stream conditions. Therefore, to improve the performance of the EFI+ in regions with high incidence of alien species, the EFI+ was adapted to include alien fish pressure as a new metric that reflects the number of alien species as well as the proportional abundance of alien individuals. The application of the adapted index (A-EFI+) is illustrated with data from several Iberian Mediterranean basins and showed similar or stronger correlations than the original EFI+ with anthropogenic pressure (land-use variables and alterations in hydrology and river morphology) and with other regional fish indices. EFI+ has been invaluable to intercalibrate fish indices across Europe, and A-EFI+ is similar but explicitly includes alien pressure, thus helping to provide a more comprehensive assessment of ecosystem health and to communicate it to society. [ABSTRACT FROM AUTHOR]

The European Water Framework Directive (WFD) is one of the most studied environmental legislations and recently turned twenty. The paper deals with a literature search and analysis of 4120 references related to this Directive. After a period of strong increase in article production (2002–2012) WFD scientific productivity is currently still high (~ 260 papers year−1), suggesting a persistent interest of the scientific community on this issue. Most research supporting the WFD was on water sciences, but contributions were also from governance and socio-economic disciplines. Studies on biological quality elements and rivers were prominent. The WFD implementation has seen a strong participation of scientists from all EU countries, and partially also from outside-EU nations. To improve the EU water policy and management, the paper suggests a greater interconnection between WFD and other EU Directives and indicates some emerging environmental issues to which the Directive should address. [ABSTRACT FROM AUTHOR]

Climate change has been increasing the frequency and severity of drought periods. There is a need to understand how this water scarcity affects aquatic communities. The main aim of this work was to compare the macroinvertebrate communities and their bioindicator value (ecological status sensu the Water Framework Directive) in three Regions [northeast (N), central (C) and south (S)] of Portugal along a water availability and climate gradient, in two consecutive years that reflect hydrologically distinct scenarios (2018 versus 2019). The period prior to sampling (summer and autumn 2017) was extremely dry and hot, whereas climatic fluctuations in 2018–2019 (when the sampling occurred) were closer to the norm. A total of 28 sampling sites were surveyed in streams of Regions where water scarcity is differentially constitutive. The results showed a consistent environmental and ecological gradient in both years, despite the background differences. A coinciding mineralization, temperature, riparian cover and water availability gradient clearly separated Regions C (wettest) and S (driest), with Region N occupying an intermediate position. Region C had overall higher ecological quality (prevalence of sensitive organisms) in both years. Despite our a priori expectations that 2018 would represent a much more stressful condition, with larger differences across Regions (because of their constitutive background), the data suggest that macroinvertebrate communities may be resilient or adapted, to some degree, to hydrological fluctuations. Signs of more favourable conditions in 2019 were also observed (general improvement in ecological status). Studies across hydrological and climatic gradients (in time and space) are particularly important where water availability is becoming more challenging. [ABSTRACT FROM AUTHOR]

Large-scale mining operations in western China would accelerate the fragility and degradation to arid ecological environments. Remotely sensed monitoring and assessing of mining effects in long term change could provide sound understanding to guide mine ecological restoration and local ecosystem sustainability. This study's primary goal is to develop an arid mined land status (AMLS) index based on remote sensing data to assess ecological effects in mining areas of arid land. Furthermore, the performance of AMLS was contrasted with that of the remote sensing ecological index (RSEI) and the land surface ecological status composition index (LSESCI) in arid mines under various landscapes conditions. Eventually, the Sen + Mann–Kendall method was used to analyze the temporal and spatial land status variations in the mining effect between 2005 and 2020 based on Landsat time-series images. The following was revealed by the results: (1) AMLS had high correlation (r > 0.65) with each factor, including bare soil flatness, dryness, land surface temperature, and slope. (2) Comparing with LSESCI and RSEI, the proposed AMLS could characterize the mining area and surrounding natural bare soil and rock with different ecological status levels in three mines, hence indicated the mining directional heterogeneity and distance attenuation of ecological status. (3) Based on time series Landsat data, the AMLS demonstrated long-term ecological variability from 2005 to 2020 due to mining and reclamation in three mines.

The mangrove ecosystem of Morosari Village, located in Sayung District, Demak Regency, Central Java, Indonesia, frequent experienced water pollution problems such as tidal flooding, abrasion and pollution due to anthropogenic activities. These problems can lead to further deterioration of water quality. This study aims to use epipelic diatoms to determine the ecological status of waters based on the diatom index in the coastal waters of Morosari Village, Central Java, Indonesia. Sampling was conducted at 3 sampling locations in July-December 2022. Samples from three stations were analyzed based on the diatom index using OMNIDIA software version 6.1.5 and RStudio Software for water quality. Four diatom water quality indices (IBD, IPS, IDG, and TDI index) were obtained that could provide a percentage value of more than 70% of diatom species. The results of the analysis showed varied ecological status and water quality. Station 1 (IBD, IDG, IPS and TDI index) ranges from 10.9 to 5.2 which is categorized meso-eutrophic to eutrophic in terms of diatom species that dominate Fallacia pygmaea and Nitzschia clausii, station 2 (IBD, IDG, IPS and TDI index) ranges from 14.3 to 6.9 which is categorized mesotrophic to eutrophic in terms of species Diatoma vulgaris and Thalassiosira pseudonana, and station 3 (IBD, IDG, IPS and TDI index) ranges from 13.9 to 3.5 with diatom species dominating Cocconeis placentula and Nitzschia palea.

Large watercourses are characterised by significant spatial and temporal changes in water quality due to both natural and anthropogenic impacts. The paper analyses changes in the Danube’s spatial and seasonal water quality in its middle part at five monitoring stations for the period 2018–2022. Examined water quality parameters include oxygen saturation (Os), ammonium (N-NH4), pH, 5-day biochemical oxygen demand (BOD), nitrate nitrogen (N-NO3), orthophosphates (P-PO4), suspended solids (SS), electrical conductivity (EC), and water temperature (WT). Furthermore, the analysis took into account the influence of two additional factors: air temperature (AT) and discharge (D). Throughout the entire period under study, all parameters were characterised by low concentration values, which met the environmental objective of good ecological status. The use of multivariate statistical methods allowed for the identification of EC, N-NH4, WT, Os, SS, and N-NO3 as determining the greatest spatio-seasonal variability of water quality in a selected section of the Danube. Regression models determined WT, EC and nitrogen nitrate changes as depending on AT, flow, and exposure time. Knowing models not only gives a better understanding of the dynamics of changes in water quality in the stretch of the Danube under study but potentially allows the prediction of these parameters based on easily measurable environmental variables.

The worldwide decline of macroalgal forests is raising major concerns for the potentially negative consequences on biodiversity and ecosystem functions, pushing for the definition of specific conservation and restoration measures. Protecting and restoring these habitats requires detailed information on their distribution, ecological status, and drivers of decline. Here, we provide the most updated available information on the distribution of Mediterranean Cystoseira s.l. forests by conducting a comprehensive bibliographic survey of literature published from 2009 to 2021, complemented by unpublished data. We also provide insights into the ecological status of these forests and the stressors affecting them across the Mediterranean basin. Our results show that most Mediterranean coasts remain un(der)studied and that the available information is concentrated in spatially limited coastal areas, restricted to very few species. When the ecological status is reported, data is highly heterogeneous, making any comparisons problematic, what claims for the description and use of easy and standardized monitoring methods for comparative purposes. Drivers of decline of Cystoseira s.l. forest have been even less investigated and, therefore, still poorly characterized. Our results highlight that our current knowledge is still insufficient to implement effective conservation and restoration strategies at the basin scale but also regionally. We call for the urgent need for mapping and standardized monitoring of Cystoseira s.l. forests to obtain baseline information for future management strategies involving their conservation, the mitigation of the stressors threatening them and the restoration of the degraded forests. [ABSTRACT FROM AUTHOR]

This paper presented the effect of the activity of the coal fired power plants „Republika" and „Bobov dol" in Bulgaria and the influence of the wastewaters discharge on the ecological status of Razmetanitsa River (Struma River catchment - West Aegean region) and Sokolitsa River (Maritsa River catchment, East Aegean region). The data of the biological quality elements macrozoobenthos, phytobenthos and fish fauna; basic physicochemical parameters, dissolved oxygen, oxygen saturation, conductivity, biological oxygen demand, ammonium nitrogen, nitrate nitrogen, nitrite nitrogen, total nitrogen, orthophosphates as phosphorus, total phosphorus, calcium (calcium carbonate hardness), total suspended substances; specific pollutants - iron, manganese, copper, zinc, aluminum, chromium total, arsenic, free cyanides, polychlorinated biphenyls, phenols, uranium, radium-226, total a-activity, total ß-activity, etc.; sulphates, chlorides; the priority substances cadmium, lead, mercury and nickel from Annex 1 of Directive 2013/39/EU were reviewed and assessed for monitoring sites before and after the discharge points from coal fired power plants in the Struma and Maritsa catchments during the period 2013-2022. A relation between the worsened biological quality elements, the exceeded values of the monitored basic physicochemical parameters and the exceeded environmental quality standards of the specific pollutants and the deterioration of the ecological status of the observed surface water bodies was established. [ABSTRACT FROM AUTHOR]

Both natural and anthropogenic processes can lead to the increasing salinity of surface waters. The knowledge about the ecological consequences of salinization on the biota is limited especially in case of microbiota, like diatoms. We collected the existing knowledge about the relationship between salinity and diatoms in fresh and saline waters. Based on the available papers, conductivity and ion composition are the most important variables shaping diatom communities. Secondary salinization can mask regional differences in diatom assemblages. Trait-based analyses highlight the competitive advantages of motile guild and the extreme trait categories in these environments. The increasing conductivity along a wide conductivity scale decreases the alpha-diversity. Salinization induces the spread and invasion of marine and brackish species into inland freshwaters as well as that of freshwater species tolerating elevated conductivity and/or need specific ions. Concerning food webs, salinity can directly change diatom communities and the subsequent upper trophic levels but most likely this effect manifests as a top-down regulation. Applicable diatom indices are available to assess the level of salinization. Furthermore, diatom-inferred salinity reconstructions are widely applied to assess the past changes of salinity. However, future models predicting ecological consequences of salinization are scarce and sometimes contradictory. [ABSTRACT FROM AUTHOR]

The mangrove ecosystem of Morosari Village, located in Sayung District, Demak Regency, Central Java, Indonesia, frequent experienced water pollution problems such as tidal flooding, abrasion and pollution due to anthropogenic activities. These problems can lead to further deterioration of water quality. This study aims to use epipelic diatoms to determine the ecological status of waters based on the diatom index in the coastal waters of Morosari Village, Central Java, Indonesia. Sampling was conducted at 3 sampling locations in July-December 2022. Samples from three stations were analyzed based on the diatom index using OMNIDIA software version 6.1.5 and RStudio Software for water quality. Four diatom water quality indices (IBD, IPS, IDG, and TDI index) were obtained that could provide a percentage value of more than 70% of diatom species. The results of the analysis showed varied ecological status and water quality. Station 1 (IBD, IDG, IPS and TDI index) ranges from 10.9 to 5.2 which is categorized meso-eutrophic to eutrophic in terms of diatom species that dominate Fallacia pygmaea and Nitzschia clausii, station 2 (IBD, IDG, IPS and TDI index) ranges from 14.3 to 6.9 which is categorized mesotrophic to eutrophic in terms of species Diatoma vulgaris and Thalassiosira pseudonana, and station 3 (IBD, IDG, IPS and TDI index) ranges from 13.9 to 3.5 with diatom species dominating Cocconeis placentula and Nitzschia palea. [ABSTRACT FROM AUTHOR]

Bakırçay is one of the important rivers of Western Anatolia, Türkiye. The objectives of this study are (a) to determine the diversity of benthic invertebrates distributed in Bakırçay, (b) to evaluate the obtained data using various biological indices, (c) to determine the interactions of species with environmental variables, and (d) to estimate the water quality level of the river using BMWP and ASPT analyses. Samplings were carried out at 15 stations between October 2017 and July 2018, seasonally. A total of 11,897 specimens belonging to 136 benthic macroinvertebrate taxa were determined. Diptera and Oligochaeta were the dominant groups with 32 (24%) and 25 taxa (18%), respectively. Station 4 has the highest species richness with 49 taxa (36%). The highest individual number (3421) was at the 14th station. Tubifex tubifex and Physella acuta have the highest dominancy (25.76%) and frequency (51.67) values, respectively. Diversity (H') values of the stations fluctuated between 1.367 (st. 13) and 3.154 (st. 12). Similarity analysis showed that the 3rd and 11th stations have the highest similarity (> 90%), while the 14th station was an outgroup and has 28% similarity ratio. BMWP and ASPT scores gave similar results, and there was no 1st class water quality in the river. On the other hand, the results of the TR-BMWP score suggested that the 1st, 4th, and 6th stations had 1st class water quality. Although some stations are classified as "good conditions," the adverse effects of pollution were mainly observed in the main channel and downstream of the river. [ABSTRACT FROM AUTHOR]

The Chagos Archipelago is a remote Indian Ocean atoll of international conservation significance. Holothurians (sea cucumbers) are a major resource and influence reef health. Past populations have fluctuated from poaching and natural events.Visual censuses of holothurians were conducted in 62 shallow‐water transects within four atolls of Chagos in 2014, 4 years after creation of the Marine Protected Area, to determine its possible influence on holothurians.Comparison with data from the same locations in 2006 and 2010, using the same methodologies, showed significant overall population decline at Diego Garcia, recovery at Salomon (significant) and Peros Banhos (not significant), and no significant change on the Great Chagos Bank.The median abundance of Holothuria atra and Bohadschia sp(p.) decreased at Diego Garcia, while that of Stichopus chloronotus increased at Diego Garcia and Salomon atolls. Changes for other species were less marked.Diego Garcia, Salomon and Peros Bahnos showed a decline in diversity (no. of holothurian taxa and/or Shannon index, H), but diversity has been relatively stable on the Great Chagos Bank.All atolls, except Diego Garcia, are uninhabited and illegal fishing of holothurians, principally by Sri Lankan fishers, appears to have eased since 2005/2006, based on evaluation of 299 patrol survey reports. This may have led to the recovery or stabilization of populations in the outer atolls of Salomon, Peros Banhos atolls and the Great Chagos Bank.The reasons for holothurian decline at Diego Garcia, where exploitation is also prohibited (but cannot be ruled out), are unclear. Population patterns on all islands may reflect both natural fluctuations and disturbance events, including changing exploitation pressure.Conservation requirements include periodic re‐censusing of holothurians and ongoing monitoring of illegal fishing to help safeguard populations and the integrity of the Marine Protected Area. [ABSTRACT FROM AUTHOR]

Hydrological (rainy and dry) periods can affect the water quality of lentic ecosystems, which may be useful for understanding their ecological condition in the watershed. Ecological status of various lentic ecosytems (both brackish and freshwater) in the western Mediterranean basin was evaluated by using various diatom metrics throughout rainy (May) and dry (August and October) periods to explain the diatom-stressor interactions using multivariate approaches. Canonical correspondence analysis separated freshwater habitats under the pressures of nitrate and total organic carbon from brackish ecosystems under the pressures of conductivity, nitrite, sulphate, calcium, and copper, which were characterized by different phytoplankton species. Ecological integrations of diatom species varied in the ecosystems throughout rainy and dry periods. Different ecological regional diatom indices were used to find the best index/indices indicating the ecological status of lakes and reservoirs in the basin during the two hydrological periods. The trophic diatom index developed for lakes was not found to be suitable for assessing lentic habitats. European diatom indices generally showed the distinction in the assessment of these ecosystems in the rainy and dry seasons, but others could not. Among the diatom indices, only the trophic index Turkey (TIT) showed a statistically significant correlation with TP. The TIT not only showed degradation of the water quality of ecosystems during the dry season compared to the rainy season, but it has also been successful in distinguishing the ecological conditions of lentic ecosystems. [ABSTRACT FROM AUTHOR]

Aquatic vegetation is a reliable indicator of the ecological condition of surface waters. Abundance, composition and spatial structure of aquatic communities are shaped by an array of factors, which include both natural abiotic features of an ecosystem and external influences. We investigated whether the physical features, i.e., wind exposure and slope of the lake basin, have a significant impact on the taxonomic composition and spatial structure of macrophyte communities from non-impacted, highly alkaline, lowland lakes of the European plains (Poland). We further examined whether these features can affect the classification of the ecological status of lakes assessed in accordance with the Water Framework Directive requirements. Morphological, botanical and physicochemical data from 260 transects in 16 non-disturbed lakes of Polish lowlands surveyed in the years 2011–2016 were analysed. For each transect, littoral slope and wind exposure were calculated. Additionally, the total phosphorus concentration was used as a proxy of water trophy. The relationships between environmental variables and macrophyte indices as well as the syntaxonomic composition of aquatic and rush vegetation (dependent variables) were analysed using multidimensional ordination techniques (redundancy analysis, variation partitioning and indicator values), correlation and regression analysis. Among the three analysed environmental factors (littoral slope, wind exposure and water trophy), in almost all cases the latter explained the highest variance in the macrophyte community, while the contribution of the first two was at most moderate, weak or usually statistically insignificant. However, lakes with steeper slopes were more frequently inhabited by stoneworts and had better ecological status than those with a gentle littoral shape. This may be attributed to the links between lake morphometry and rate of eutrophication, with deep lakes supporting more effective dilution of substances. Furthermore, lower light requirements of charophytes than of higher plants and the capacity to growth in unstable sediments facilitate charophyte establishment in deeper and steeper parts of the littoral over higher plants. Our findings suggest that in lowland lakes with relatively small areas, moderate depths and low wind exposure typical of European plains, slopes and weaving do not hamper vegetation development and do not negatively affect the macrophyte assessment of ecological status. In such ecosystems, eutrophication seems to be a more important factor determining aquatic vegetation than physical features.

With the rapid growth and development of urban areas, the economy has often been prioritized at the expense of the environment and ecological systems. However, it is essential to delve deeper into the relationship between the economy and the ecological environment. Therefore, this study introduces a comprehensive evaluation system that encompasses economic, ecological, and environmental factors in the Beijing–Tianjin–Hebei urban agglomeration in China. The Criteria Importance Through Inter-criteria Correlation (CRITIC) method is utilized to determine the weights of various indicators, and coupling as well as coupling coordination models are employed to investigate the spatiotemporal trends and interrelationships of the three factors. The results indicate that the economic development index has displayed a consistent uptrend since 2000, with the economic development index from 2015–2020 increasing by approximately four times compared to 2000–2005. The ecological status index has also increased in the last five years, with a rise of about 0.05 from 2015–2020 compared to 2000–2005. The environmental status index has fluctuated but generally increased, with a rise of approximately 5.6 times from 2015–2020 compared to 2000–2005. The coupling degree of the Beijing–Tianjin–Hebei urban agglomeration is relatively high, with intense coupling from 2005–2020, and moderate coupling from 2000–2005. Furthermore, the coupling coordination has continuously improved from mild maladjustment to barely coordinated from 2000 to 2020, indicating the enhancement of the coupling coordination of the three factors. It is crucial to acknowledge that there exists spatial heterogeneity in both the coupling degree and coupling coordination degree. This heterogeneity stems from the uneven progress in economic development, ecological conditions, and environmental status across various cities. Additional endeavors are required to foster the harmonized advancement of these factors across the entire region.

Abstract Background For more than 20 years, restoration measures have been conducted on watercourses in Germany to increase habitat diversity and thus promote biodiversity. However, their ecological efficacy often proved to be limited. While some studies report an increase in species diversity, others show little evidence of improvement even many years after the implementation of restoration measures. In general, ecological efficacy of hydromorphological restoration measures is highest for terrestrial and semiaquatic groups of organisms such as floodplain vegetation and ground beetles. According to the literature, macrophytes responded most strongly to in-stream restoration measures, while fish stocks showed little improvement and macroinvertebrates showed little or no effect in terms of species richness and diversity. These findings raise the question of reasons for the low ecological efficacy of hydromorphological restoration measures, especially for macroinvertebrate communities. The following literature review and a case study for the river Horloff will provide possible indications for failing success of intensive restoration measures. Results One reason for the inadequate ecological status of many restored river stretches is the inappropriate scaling of restoration measures. Often, small-scale restoration measures are planned, although the respective water bodies exhibit stressors at the catchment scale that impair the ecological efficacy of restoration measures. In particular, chemical contamination of running waters is often insufficiently addressed in the planning and implementation of restoration measures and hampers efficacy of hydromorphological restoration measures. For a holistic water resource management, the planning and implementation of measures should therefore be more closely coordinated and harmonized between federal states and neighboring countries. For this purpose, the establishment of so-called river basin communities is suitable, as they already exist today on the rivers Rhine, Danube, Meuse, Weser, Elbe, Ems, Eider, Schlei/Trave, Warnow/Peene. Conclusion The literature review indicated that for a successful recolonization of restored river stretches by macroinvertebrates and the enhancement of the ecological status, large-scale stressors, i.e., stressors acting at the catchment scale, should be eliminated initially by restoration measures focusing on the chemical contamination and the surrounding land use. Structural restoration measures acting on the reach or local scale should ideally be implemented contemporarily to the removal of large-scale stressors like chemical contamination.

The urban rivers, Changwang, Meishe, and Wuyuan, are vital water resources in Haikou City, China. However, pollution from various anthropogenic activities negatively impacts their ecological status. This study aimed to develop and compare the performance of a minimum water quality index (WQImin) and phytoplankton index of biotic integrity (P-IBI) in assessing the rivers' ecological status for protection purposes. Samples were collected and analyzed seasonally from March to December 2019. The results revealed that TP, DO, COD, TN, and turbidity were critical for developing the WQImin. The WQImin values showed no significant spatial and seasonal differences. Thus, it rated the rivers “moderate,” with the highest and lowest WQImin values in winter and summer. The P-IBI was developed using phytoplankton density, Chl-a, biomass, and Margalef richness. Notably, the P-IBI values differed significantly at seasonal but not spatial scales. It rated Changwang and Wuyuan “moderate,” whereas Meishe was “low.” Moreover, Autumn and summer had the highest and lowest P-IBI values. Interestingly, the P-IBI demonstrated that parameters such as COD, TN, NH4+-N, EC, pH, turbidity, and temperature decreased with improving water quality, while water transparency increased with improved water quality. The WQImin and P-IBI assessment results were consistent. The indices showed that summer had poor water quality than other seasons. In addition, the indices negatively correlated with the trophic level index (TLI). In contrast, the P-IBI ratings were significantly lower than WQImin at spatial and seasonal scales. Hence, this study suggests that WQImin and P-IBI can effectively assess the ecological conditions of the rivers and that the critical parameters and metrics for their development might vary in different regions. In addition, P-IBI may provide stricter standards than WQImin for water quality assessment.

The study's goal was to evaluate the Jiu River's potential for having high-quality water while taking into account the typical values of the physico-chemical parameters. We created the water purity class from an ecological point of view using components and national physic-chemical quality criteria based on the 18 physic-chemical characteristics found in three sample stations. With the exception of P-PO4 class IV for all three water segments, the majority of metrics fall into quality class I; TP (class III, IV, III); N-NO2 (class II, III, III). The 8 metrics' WQI values change depending on the segment under study: Excellent (DO, BOD, Nitrate, Phosphates, pH); Good (TDS; BODSJ3); Bad (Temperature); and Very Bad (Turbidity) are the other parameters. In summarizing the findings, it can be said that the overall WQI's quality index changes very little. 79, 78, and 77, all of good quality, are deteriorating near the Jiu River's southern branch in Gorj County. WQI value decrease continues on Dolj County respectively: 67, 64, and 63 in the direction of flow to the Danube River. This may be explained by taking into consideration the human stresses that the watercourse is subjected to from major, intermittent, and dispersed sources on the territory of two nations. [ABSTRACT FROM AUTHOR]

The terms 'non-native', 'non-indigenous', 'alien', and 'exotic' refer to species or races that do not occur naturally in an area, i.e., they have not previously existed there, or their dispersal into the area has been mediated by humans. In a broad sense, these terms can refer to species that may originate within the same region or country but not occur naturally in a particular water body until colonization is facilitated by humans. In Bulgaria, some efforts have been made to summarize the distribution of alien fish species, but nothing is known about the translocated species. Here, both groups are considered according to the Water Framework Directive's (WFD) classification of lotic ecosystems: the main ichthyogeographical regions, the river typology, and the ecological status of the Biological Quality Element (BQE) "Fish". In total, 7 alien species and 15 translocated species were established, with approximately the same total number of specimens. In general, even though the relative abundance of non-native species reaches 100% in single cases, their total numbers are low, compared to native species. Concerning certain basins/river types, these percentages are slightly higher, due to a complex of parameters determining their distribution: environmental factors (hydromorphological) reflecting the ecological (species' requirements and tolerance) factors. Some river types are more vulnerable to colonization. The relative abundances of the non-native fish species per sampling site showed a weak connection with the ecological status of the BQE "Fish". As the distribution of organisms is affected by environmental parameters and biotic interactions, standardized multiannual data, as viewed by the WFD, could become a solid basis for elucidating various aspects of this complex issue. [ABSTRACT FROM AUTHOR]

Sustainable finance and green trade are essential to accomplish the green growth agenda. Though the literature prevails, little is known about the inclusive influence of financialization and trade openness on ecological status rather than just focusing on air pollution or inconclusive element. This study aims to analyze the role of financial dimensions and trade openness with environmental performance in the context of three panels of Asian countries consisting of low, middle, and high-income over the period 1990–2020. The estimated outcomes from the novel panel, the Granger non-causality technique, demonstrate that financialization further contributes to environmental deterioration instead of preserving the environmental quality. Regarding the low and middle-income economies, the authorities should enhance gains from trade openness to develop energy efficiency and ecological status policies. In the case of high-income Asian countries, they are even more desperate to consume energy and ignore the ecological challenges. The findings of this research offer various policy suggestions to accomplish sustainable development objectives. [ABSTRACT FROM AUTHOR]

Romanogobio banaticus it is a species of conservation interest with a small distribution range in the south-west of the Romanian Carpathians basin. In spite of the presence of some moderate anthropogenic threats and risks, the Nera River is a sanctuary for this fish. The lower latitude of Nera in comparison with other rivers where this fish is living, explain its presence in an atypical ichthyological zone. This species presence is permanent, the abundance is relatively high, the age structure is well balanced, more than that, in some sectors is a co-dominant species, all of these revealing a favourable conservation status. [ABSTRACT FROM AUTHOR]

River ecosystems host a large biodiversity and provide essential ecosystem services but are threatened by multiple anthropogenic activities that degrade their structure and functioning. Although both structure and functioning are key components of ecological status, river monitoring programmes rely almost exclusively on structural indicators, such as community structure, or water quality, neglecting functional attributes. Scientists have pointed towards some promising functions, such as organic matter decomposition, as potential indicators of river functional status. However, it may not be the best indicator to assess the ecosystem functioning of river ecosystem subjected to certain impacts, such as nutrient inputs. Additionally, managers have seldom used functional indicators, probably because of the lack of simple, routine protocols. Here we present the nutrient uptake bioassay (NUB), a simple and straightforward method to measure nutrient uptake by river biofilm that could be developed as a functional indicator of river ecological status. The NUB consists in deploying biofilm carriers in the river for a specific period, allowing biofilm colonization. Biofilm carriers are then incubated in the field in a nutrient-enriched standard solution for one hour and finally the remaining nutrient concentration in the standard medium is measured. Nutrient uptake is calculated from the difference between the initial and final nutrient concentrations. Chlorophyll in the biofilm carriers can also be measured to calculate biofilm accrual rates. The NUB has been developed based on a mesocosm and a field experiments, which showed that the NUB provides additional, non-redundant information to current biomonitoring techniques. Overall, the NUB is a cheap, robust and reliable method that can be applied by most river monitoring practitioners and can be adapted to most river types and situations. As nutrient uptake is linked to the self-purification capacity of rivers, the NUB results provide information about an important ecosystem service. Therefore, we suggest that the NUB can be developed as part of the monitoring toolbox available for managers to improve the assessment of river ecological status and to diagnose the causes of ecosystem impairment.

The primary objective of this paper was to assess the condition of riparian zones within urban environments, aiming to evaluate the ecological health and functionality of riparian areas through the examination of various indicators, including (but not limited to) vegetation cover, water quality, stream channel morphology and habitat complexity. Such an evaluation is essential to identify areas that require restoration or conservation efforts and develop appropriate management strategies to ensure their effective protection. The present paper is the outcome of investigations that employed a comprehensive research framework, consisting of desk research, field surveys and data analysis. The desk research was utilized to combine the existing knowledge regarding riparian zones and water bodies research methods. The field surveys were conducted to gather empirical data concerning riparian vegetation cover, stream bank erosion and water quality. Data analysis was conducted to identify patterns and trends and determine areas of concern. This work contributes to the overall field of riparian area management by providing an assessment of riparian area conditions in the study area. The findings of the study can be used to inform conservation and restoration efforts and to guide the development of effective management strategies. The paper also highlights the need for ongoing monitoring and evaluation of riparian areas to ensure their continued health and functioning. [ABSTRACT FROM AUTHOR]

Diatoms, silicious microalgae, have been used successfully as bioindicators of water quality assessment in aquatic ecosystems. Diatoms have a degree of tolerance to the water quality and some diatoms are a good indicator for several water quality variables. Diatom indices have been developed to assess river water quality, mostly in Europe. This study aims to apply diatom indices developed in Europe for the tropical lake of Galela adjacent to residential areas influenced by human activities. Galela Lake is one of the biggest lakes in Halmahera Utara, Indonesia with its main functions being domestic water supply, irrigation, fisheries, and tourism. Human activities have impacted the area around the lake. The 90-cm and 85-cm long sediment cores were collected using a piston corer from Site 1 and 2, respectively. Sediment samples were sliced every 5 cm, separated from sediment by adding HCl and H2O2. The diatom valves were identified under a microscope with 1,000 × magnification. The water quality status of each layer was inferred with diatom indices performed using OMNIDIA software version 6.0. Forty-nine and 63 diatoms species were identified from Site 1 and Site 2, respectively. The number of species and diversity of diatoms was higher in the lower layers than those in the upper layers. The preserved diatom assemblages reflect past physical and chemical water quality. Generic Diatom Index and Specific Pollution Sensitivity Index provided the best evidence for change in Galela Lake—they integrated 70–100% of the diatom taxa from the sediment core samples. [ABSTRACT FROM AUTHOR]

The aims of the present study were to investigate the macrobenthos communities in the Caspian Sea and to investigate the pollution of this ecosystem based on the pollution indices ABC (Abundance Biomass Comparison), BC (Biotic Coefficient) and ABC curve in 2018 (autumn and winter) and 2019 (spring and summer). According to the results, polychaetes, crustaceans, and bivalvia formed the major groups of macrobenthos communities with 4, 11 and 1 species, respectively. The polychaetes (mainly Streblospio gynobranchiata) included about 70% of the total abundance and the group of bivalvia (Cerastoderma glucaum) included about 76-93% of the macrobenthos in all seasons except in spring. The mean values of the Shannon index and evenness indices were calculated as (1.56) and (0.55), respectively. The annual pollution (ABC) and BC indices were obtained as -3.1 and 2.7, respectively. These values along with characteristics of ABC curve indicate severe stress caused by pollution in the Caspian Sea ecosystem. In this study, the percentage abundance of the invasive species S. gynobranchiata in macrobenthos communities was 52%, which is about 10% decrease compared to 2009 and 2010. This decreasing trend can be considered as positive evidence in the improvement process of the ecosystem in this part of the food chain. However the continuity of recovery trend needs more time, no force by new stressors, proper management, and reduced pollutions into the ecosystem.

Stony reefs are ecologically important, providing irreplaceable ecosystem services. These fragile environments are recognised as conservation priorities by all relevant global and European policies. Bottom-contacting fisheries are an important source of anthropogenic disturbance to the seafloor’s physical and ecological integrity having immediate and destructive consequences on stony reefs and compromising ecological functions. This study, aimed to assess the ecological status (community composition and functions) of two stony reef areas -Northwest and Hinder Banks study sites -in Belgian waters using multiple remote sensing tools. Insights on the study sites’ geomorphological context and fishing patterns were gained using echo-sounding and publicly available satellite data. Video-based benthic community data were assessed against the exposure to fishing pressure using a trait-based approach linked to the biotas’ resistance and recovery potential. In the Northwest study site, between 2019 and 2022 there was a significant decline in the abundance of benthic species classified with low resistance and recovery potential to trawling. Conversely, there was a notable increase in species with moderate scores. During the same period, this site experienced an eight-fold increase in fishing effort and the hydroacoustic data revealed the presence of several trawl-marks in 2022. Similar changes in benthic communities were observed in the Hinder Banks too. Here, the abundance of species with low resistance and recovery potential was significantly lower in locations that were geomorphologically exposed to trawling compared to sheltered ones. Exposed locations had a higher abundance of opportunistic species, with moderate to high scores. The presence of several trawl marks on the seafloor was observed in the exposed locations, corresponding to fishing hotspots identified in the satellite data. Trawling activities marginally impacted richness and total abundance, but negatively altered benthic functional composition. The findings of this study provide scientific evidence of the detrimental impact of bottom-contacting fisheries on conservation priority biotopes and argues against the coexistence of such activities with Marine Protected Areas. The results of our investigation are of interest to environmental managers for the adequate implementation of environmental legislation in the face of rapid and widespread anthropogenic changes.

This paper reports current ecological status of B. huillensis in Mtunguru Forest Reserve (MFR) using 90 sample plots of 400 m2 at 500 m intervals along 10 transects. The forest composition was assessed in terms of stem density, basal area and diameter class distribution of tree species including species of B. huillensis. The results revealed that the status of the forest was declining due to illegal harvesting of forest products such as firewood, construction materials and charcoal burning. It was observed that B. huillensis occurred in all 90 sample plots out of 94 tree species recorded, the B. huillensis contributed 38% of total tree density and frequency of hundred percent. Total density of trees ≥5 cm DBH was 380 tree stems ha−1 with a Basal area of 12 m2 ha−1, where the share of B. huillensis stems was 143 ha-1 with a basal area of 6.01 m2 ha−1. The stem size class distribution of species showed less density of individuals in lowest girth class (5–10 cm DBH) and the same for B. huillensis was observed in girth class (< 16 cm DBH). The result indicates the recruitment young individuals are severely affected probably because of high disturbance of the forest understory. This study indicates poor conservation status of forest reserve under Miombo woodland and status of B. huillensis under threatened category, and thus better forest management plans are needed to ensure sustainable livelihood of the inhabitants.

The increasing stress on lake ecosystems is affecting their functioning such as providing goods and services to inhabiting organisms and riparian communities. Monitoring of water quality is important for sustainable management and restoration of lake ecosystems. However, the costs associated with traditional approaches have become prohibitive, while not giving reliable early warning signals on resource conditions. Thus, the current shift in the use of bioindicators and multimetric indices (MMIs) in the monitoring of water quality is currently gaining global recognition with more emphasis on its application in lotic ecosystems. Therefore, this paper provides an elaborated insight into the application of macroinvertebrate-based MMIs in lentic ecosystems and the successes achieved so far. The various metrics and indices, the development strategies, application challenges, the use of macroinvertebrates as bioindicators, and the future projection of enhancing MMI usage in lentic environment monitoring, particularly in developing countries, are extensively covered. The use of MMI as a rapid lake biomonitoring tool needs to be adopted for sustainable applications in lake ecosystem management and as an integrated approach to monitoring human-induced stress especially in developing countries where there is a paucity of information. [ABSTRACT FROM AUTHOR]

We studied the ecological and functional aspects (such as role in sediment characteristics and plant–animal interactions) of a Ruppia cirrhosa (Petagna) Grande meadow during its vegetative season in the choked Valle Campo lagoon, a sub-basin of the wider Valli di Comacchio, on the Northern Adriatic coast. Sampling campaigns were carried out with a roughly fortnightly frequency in 2017 at two sites, one with the Ruppia meadow and one with bare sediment. Sediment parameters analyzed were microphytobenthic chlorophyll-a, protein, carbohydrate, and lipid content, and total organic matter. The macrobenthos was identified at the lowest possible taxonomic level. Chlorophyll a, as a surrogate of microphytobenthos, showed differences between the two sites, probably mainly related to light intensity; thus, it is expected that the absence of seagrass canopy results in the higher production of microphytobenthos. At both sites, proteins were the dominant class of labile compounds, suggesting that detrital organic matter present at both study sites is of high nutritional quality. The high protein/carbohydrate ratio also suggests the presence of non-aged organic matter. We recorded a total of 18 macroinvertebrate taxa. The Ruppia meadow showed a positive influence on macrofauna abundance, diversity, species richness, and composition of trophic groups. Only the infaunal taxa Capitella capitata and Chironomus salinarius exhibited higher abundance at the bare site. The ecological quality status measured by the M-AMBI index was unsatisfactory everywhere. However, the presence of the Ruppia meadow resulted in index values being consistently higher. The role of this minor seagrass has been proved to be of great importance, improving the nutritional quality of the organic matter in the sediments and, above all, providing new habitats and new niches for a number of benthic macrofauna species. [ABSTRACT FROM AUTHOR]

Context: The influence of anthropogenic pressures on plankton communities in well-flushed estuaries has been overlooked. Owing to this ecosystem's short water-residence time, they are foreseen to be mainly composed of microorganisms from neritic–oceanic sources, more resilient to anthropogenic impacts. Aims: This study characterises the bacterioplankton of Urdaibai, a small-drainage estuary located at a UNESCO biosphere reserve, to unravel its annual dynamic and ecological status. Methods: Amplicon sequencing was used to assess the euhaline bacterioplankton shifts and microgAMBI index depicted the ecological status of the estuary. Key results: A differentiated community was identified in upstream waters throughout the year. In addition, organisms commonly associated with faecal waste were detected. The ecological status of the estuary was poor or moderate along the annual cycle, but surprisingly worsened during winter. Conclusions: The above suggests that the bacterial community dynamic in this well-fluxed small-drainage estuary is more complex than anticipated. Importantly, the analysis of pollution-indicative bacteria proved that the water policy of this estuary needs to be further evaluated. Implications: The completion of an efficient sewage treatment system for this protected and touristic estuary is strongly recommended. Incorporating bacterial information to its current monitoring system will constitute a useful and valuable tool. Microbial community composition of small-drainage estuaries is expected to be mainly composed of coastal organisms. However, results obtained in this study showed that the complexity of the prokaryotic community in such ecosystems is higher than previously thought. Additionally, Urdaibai estuary evidenced to be affected by anthropogenic and terrestrial-origin factors, showing to be in a poor or moderate ecological status according to bacterial indicators. This is of special concern because this estuary is an UNESCO Biosphere reserve. [ABSTRACT FROM AUTHOR]

Background: For more than 20 years, restoration measures have been conducted on watercourses in Germany to increase habitat diversity and thus promote biodiversity. However, their ecological efficacy often proved to be limited. While some studies report an increase in species diversity, others show little evidence of improvement even many years after the implementation of restoration measures. In general, ecological efficacy of hydromorphological restoration measures is highest for terrestrial and semiaquatic groups of organisms such as floodplain vegetation and ground beetles. According to the literature, macrophytes responded most strongly to in-stream restoration measures, while fish stocks showed little improvement and macroinvertebrates showed little or no effect in terms of species richness and diversity. These findings raise the question of reasons for the low ecological efficacy of hydromorphological restoration measures, especially for macroinvertebrate communities. The following literature review and a case study for the river Horloff will provide possible indications for failing success of intensive restoration measures. Results: One reason for the inadequate ecological status of many restored river stretches is the inappropriate scaling of restoration measures. Often, small-scale restoration measures are planned, although the respective water bodies exhibit stressors at the catchment scale that impair the ecological efficacy of restoration measures. In particular, chemical contamination of running waters is often insufficiently addressed in the planning and implementation of restoration measures and hampers efficacy of hydromorphological restoration measures. For a holistic water resource management, the planning and implementation of measures should therefore be more closely coordinated and harmonized between federal states and neighboring countries. For this purpose, the establishment of so-called river basin communities is suitable, as they already exist today on the rivers Rhine, Danube, Meuse, Weser, Elbe, Ems, Eider, Schlei/Trave, Warnow/Peene. Conclusion: The literature review indicated that for a successful recolonization of restored river stretches by macroinvertebrates and the enhancement of the ecological status, large-scale stressors, i.e., stressors acting at the catchment scale, should be eliminated initially by restoration measures focusing on the chemical contamination and the surrounding land use. Structural restoration measures acting on the reach or local scale should ideally be implemented contemporarily to the removal of large-scale stressors like chemical contamination. [ABSTRACT FROM AUTHOR]

Remote sensingmonitoring of regional ecological quality has advanced significantly with the rapid developments of remote sensing technology. At present, remote sensing ecological index (RSEI) has been widely used in ecological status monitoring. However, RSEI was proposed for urban environments, and the rationality and accuracy of its applicability to desert-dominated arid region ecosystems need to be demonstrated. Therefore, in this study, we incorporated desertification monitoring index (DMI) and salinity monitoring index (SMI) to RSEI and developed the modified remote sensing ecological index (MRSEI) for arid regions. Moreover, we analyzed the stability of MRSEI in ecological status monitoring for arid regions. The MRSEI was then used to evaluate the ecological quality of Inner Mongolia from 2000 to 2020 and exploring its causes. The results show that (1) Although the evaluation results of RSEI and MRSEI are more consistent in areas with high ecological status grades, the MRSEI results are more cautious and reliable in extreme conditions (e.g., desertification, salinization) than the RSEI. (2) Approximately 87.66% of ecological quality have improved or remain stable from 2000 to 2020, but the remaining areas (accounting for 12.34% of the whole area) are still under degraded conditions. This demonstrates that although local governments have made some progress in ecological conservation, the areas that are fluctuating or degraded still require protection or management. (3) In Inner Mongolia, the ecological quality which drove by precipitation (P) & temperature (T) accounting for 26.67% of the study area, population density (D) and GDP per capita (G) affected 13.23% of regional ecological quality. Overall, this research is crucial for evaluating spatial and temporal changes in arid region ecology and establishing conservation strategies. [ABSTRACT FROM AUTHOR]

Relating biological patterns to the physical environment is increasingly explored in current period of global biodiversity crisis and attempts to identify ecological status. Free-living marine nematodes (FMN) were proposed as ecological indicators, although often under approaches based on developing synthetic indexes of environmental quality, contextually neglecting the crucial issue of their spatial and temporal variability in abundance and diversity, and its relationship with environmental drivers. This study, carried out on the north-eastern coast of India as a region subject to various anthropogenic activities, assessed the patterns of FMN structure, richness, equitability, trophic guilds, life strategy and morphological traits at three sites, three times over 1 year, two beach levels and three sediment layers upto 15 cm deep. Nematode patterns were then related to the amount of sand, silt and clay, organic carbon, and salinity. Each FMN characteristic was largely variable in time and space, being organic carbon and salinity the environmental variables most correlated to such patterns. Monitoring designs suited to capture such variability are recommended to improve the use of FMN as bioindicators. Just relying on unidirectional data to define environmental status is questioned, while it is proposed to consider the Effect of Positional Constraints when assessing ecosystem health. [ABSTRACT FROM AUTHOR]