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The Nanhui-east-tidal-flat (NETF), the largest marginal shoal in the Yangtze River of China, is significantly impacted by human activities. Prior research has not detected the presence of green macroalgae in the NETF, nor has it explored the effects of reclamation on the distribution of macroalgae. However, in 2021, a small-scale aggregated attached algal mats emerged in the NETF, potentially signaling the onset of a green tide and necessitating vigilant monitoring. Morphological and molecular biological identification analysis revealed that all collected green macroalgae were attributed to a single dominant species, Ulva prolifera , characterized by broad blades and prominent air bladders, colonizing various substrates. The attached U. prolifera exhibited continuous growth from March to May 2021, peaking at a wet weight of 373.6229 g/m² and a dry weight of 72.7904 g/m² on May 1, 2021, within the accessible sampling period. The rapid proliferation of the "opportunistic" Ulva was facilitated by high-level eutrophication and favorable environmental conditions. Furthermore, six potential germplasm sources of U. prolifera are summarized. The dominance of Ulva in the intertidal zone often indicates high eutrophication and deteriorating ecological conditions. With long-term reclamation and repeated ecological restoration projects, the intertidal vegetation is subjected to a vicious cycle of growth and destruction. Therefore, it is important to recognize that U. prolifera germplasm (macroalgae and micropropagules) will persist over the long term, and mudflats with monotonous and eutrophic habitats are highly likely to experience future large-scale algal blooms. Notably, a small-scale floating green tide was observed in the sea area near NETF in July 2023, and such concerns are not unfounded. This study conducts foundational scientific research on the attached green tide algae, a type of research that is relatively scarce in other marine areas. Most studies tend to initiate foundational research only after the outbreak of green tides, lacking early background data from the marine environment, thus rendering this study of significant reference value. Concurrently, this study emphasizes that field surveys remain an essential approach for conducting foundational scientific research on green tide algae in the NETF region, with the need to select appropriate research methods based on the occurrence and development of algal mats, as required by the situation. Importantly, this study reflects the stability of marine ecosystems as a prerequisite for modern ocean management and services, provides new perspectives on the occurrence and development of green tides, and highlights potential ecological risk factors that should be considered in the implementation of intertidal construction projects. [ABSTRACT FROM AUTHOR]

Microplastic (MP; plastics 5 mm or less) pollution appears to be ubiquitous, leading to concerns on how MPs affect organisms. While some plastics are manufactured at a small size, most MPs are broken down from larger plastics with often unknown origin. With documented risks of intestinal blockage, false satiation, and developmental dysfunction in organisms, understanding how MPs move through food webs is imperative to determine what organisms may be predisposed to MP pollution and where to focus regulations. Terrestrial birds have the potential to strategically inform researchers about MP pollution, since they are incredibly diverse, span many different habitats and behaviors, and are readily accessible to study. However, research is lacking for how important this group is as ecological indicators, with most studies focused on aquatic birds and those that exist on terrestrials focus on larger raptors. This review details the origins of MPs, their potential toxicity, movement through the environment, and our understanding of the role terrestrial birds play in ingestion and movement of MPs. Research on this topic is increasing, with plastics found in almost all terrestrial species that were sampled in the reviewed studies. Recent findings and future interests are focused on the varying levels of MPs in terrestrial bird species, likely due to individual behavior, morphology, and daily habitat use. [ABSTRACT FROM AUTHOR]

In an era of ongoing biodiversity, it is critical to map biodiversity patterns in space and time for better‐informing conservation and management. Species distribution models (SDMs) are widely applied in various types of such biodiversity assessments. Cross‐validation represents a prevalent approach to assess the discrimination capacity of a target SDM algorithm and determine its optimal parameters. Several alternative cross‐validation methods exist; however, the influence of choosing a specific cross‐validation method on SDM performance and predictions remains unresolved. Here, we tested the performance of random versus spatial cross‐validation methods for SDM using goatfishes (Actinopteri: Syngnathiformes: Mullidae) as a case study, which are recognized as indicator species for coastal waters. Our results showed that the random versus spatial cross‐validation methods resulted in different optimal model parameterizations in 57 out of 60 modeled species. Significant difference existed in predictive performance between the random and spatial cross‐validation methods, and the two cross‐validation methods yielded different projected present‐day spatial distribution and future projection patterns of goatfishes under climate change exposure. Despite the disparity in species distributions, both approaches consistently suggested the Indo‐Australian Archipelago as the hotspot of goatfish species richness and also as the most vulnerable area to climate change. Our findings highlight that the choice of cross‐validation method is an overlooked source of uncertainty in SDM studies. Meanwhile, the consistency in richness predictions highlights the usefulness of SDMs in marine conservation. These findings emphasize that we should pay special attention to the selection of cross‐validation methods in SDM studies. [ABSTRACT FROM AUTHOR]

In natural restoration, it is important to improve the efficiency of monitoring. Remote sensing using unmanned aerial vehicle (UAV) platforms plays a major role in improving monitoring efficiency. UAV platforms are particularly suited for monitoring long-term, multitemporal changes. The objectives of this study were to develop a standard protocol for monitoring multitemporal changes in forest indicator species using a UAV platform, to evaluate multitemporal changes, and to examine the factors contributing to these changes. The study site was a forest located within Takaragaike Park (Sakyo-ku, Kyoto, Japan), and Rhododendron reticulatum was selected as the study species. The distribution of R. reticulatum flowers was identified from 2019 to 2023 using image recognition with artificial intelligence. A mesh was used as a spatial unit, and standardized values (Z values) were tabulated to evaluate the abundance and changes in the number of R. reticulatum flowers over time. The method used in this study showed very high accuracy in image recognition at multitemporal periods, indicating that it is useful for long-term monitoring. It was also able to detect the effects of forest management and the impact of vegetation succession. The new method is expected to become one of the standard protocols for understanding multitemporal changes in forest indicator species. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions We aim to refine the definition of peri‐Carpathian forest‐steppe grasslands, provide an updated distribution map, identify consensus indicator species and summarise data on their extreme species richness.East‐Central Europe (Czech Republic, Austria, Slovakia, Hungary, Romania, Ukraine).Vascular plants.A total of 127 vegetation plots from large vegetation databases and field sampling were classified as the Brachypodio‐Molinietum association based on two criteria: (1) the existing formal definition and (2) a threshold of consensus indicator species derived from a literature review. The plots were mapped, and their basic habitat conditions were characterised. Habitat affiliations of consensus indicator species were expressed using the diagnostic species lists in the EuroVegChecklist. Maximum species richness values were extracted from the plot data and summarised.Peri‐Carpathian forest‐steppe grasslands of the Brachypodio–Molinietum association have been recorded across a large area of East‐Central Europe, particularly in the lower to middle altitudes of the Western and Eastern Carpathians and their foothills and adjacent regions. These grasslands typically occur in moderately warm, relatively precipitation‐rich regions with deep soils, primarily on plateaus and gentle slopes of up to 10°, developed predominantly over less consolidated Mesozoic and Tertiary sedimentary rocks. We identified 60 consensus indicator species, mostly species of forest‐steppe habitats, with species of mesic grasslands also well represented. The current maxima of vascular plant species richness exceed 110 species per 10–16 m2. These maxima have been recorded in three regions: the Prut‐Siret Interfluve in western Ukraine, the NW Transylvanian Basin in Romania and the White Carpathian Mts in the Czech Republic.The extremely species‐rich peri‐Carpathian forest‐steppe grasslands are confined to a geographically well‐defined area of East‐Central Europe. The observed fine‐scale species richness of vascular plants is currently the highest known in the world. In addition to similar habitat conditions, the presence of an ancient forest‐steppe species pool appears to be a prerequisite for such extreme species richness. Recent paleoecological evidence supports this hypothesis. [ABSTRACT FROM AUTHOR]

The biotic integrity of streams is frequently compromised by anthropogenic disturbance; thus, it is important to study the potential mitigating effects of undisturbed riparian zones on streams within disturbed watersheds. In this study, two first-order northern Michigan streams located 1 km apart in adjacent agricultural watersheds, but with differing riparian land use, were compared to observe the effects of intact forest within the immediate 100 m stream corridor. Both streams had high specific conductance values associated with agricultural streams. The stream with a primarily forested riparian corridor, however, had greater canopy cover, faster stream velocity, greater coarse substrate, lower percentage of organic sediment, lower water temperatures, higher dissolved oxygen, higher taxonomic richness, higher relative biomass of shredders, lower relative biomass of gathering collectors, and more pollution intolerant taxa than the stream with a primarily agricultural corridor. Moreover, the benthic macroinvertebrate assemblages were highly distinct from each other, with the riparian forested stream dominated by aquatic insects like mayflies and caddisflies, and the agricultural stream by non-emergent isopods and amphipods. These results demonstrate the effects of a buffer zone on stream substrate composition, water physicochemistry, and benthic assemblages, and indicate the importance of preserving riparian zones within agricultural watersheds. KEY POLICY HIGHLIGHTS: Agricultural pollution remains a threat to river systems throughout much of the Upper Midwest, including small streams in northern Michigan. Preserving riparian corridors adjacent to small streams within overall agricultural watersheds helps to decrease fine particulate organic matter input and maintain taxonomic richness of benthic macroinvertebrates, even without obvious improvements to water quality. Preserving these "refuge habitats" is critical to maintaining the organismal diversity and biotic integrity of river systems within larger agroecosystems; thus, their identification and protection should be a policy priority. [ABSTRACT FROM AUTHOR]

The popularity of taxonomic diversity calculations in diversity studies of natural ecosystems is increasing. As a solid alternative to species diversity, taxonomic diversity indirectly provides information about species' functional and structural features. This performance of taxonomic diversity has a significant effect on the association of plant communities explained directly or indirectly by environmental variables. This study aimed to determine the relationships among environmental factors, taxonomic diversity and vegetation groups. The vegetation groups were then determined using cluster analysis. The indicator plant species that are effective in the differentiation of each group were also identified, and a phylogenetic tree was obtained to evaluate the taxonomic dissimilarity of these species. The relationships of Bio1, Bio12, elevation, slope, radiation index, and soil depth variables with group distinctions and taxonomic diversity values were revealed through principal component analysis. Results also showed that the species in the same group are also taxonomically close to each other. As elevation increases in the study area, taxonomic diversity decreases. Forest tree species are distributed as mixed stands in relatively higher areas of the region, and herbaceous and shrub species show relatively less diversity in these areas. Additionally, all the indicator plant species in the group showing the highest relationship with elevation are forest tree species, which further supports the results. [ABSTRACT FROM AUTHOR]

The data on the reptilian fauna of the state of Goiás are one-off and reveal a lack of information about this group. The aim of the research was to know the composition of the reptile fauna within the area of the Anglo American mining company, evaluating the relationship of the species with the years, the types of environments and the presence of indicator species. Fieldwork was carried out during seven years, from 2007 to 2013. Sampling was performed through active search, pitfall traps, occasional encounters, and third-party records. We recorded 36 reptile species: 15 lizards and 21 snakes. The most common lizards were Anolis meridionalis, Cnemidophorus sp, and the most abundant snakes were Apostolepis cerradoensis and Bothrops moojeni. There was no relationship between the species and the years. On the other hand, there was relationship between the species and the environments or between the species and the types of habitats. The lizard Ameivula ocellifera was found as an indicator species of Cerrado areas, as well as the snake Leptotyphlops dulcis We have seen that lizards are specific to their habitat, making it essential to preserve open and forested areas for the conservation of the species that live there. [ABSTRACT FROM AUTHOR]

Within the family Amylocorticiaceae, conspicuous morphological affinities exist among the previously defined species Irpicodon pendulus, Plicaturopsis crispa and Plicatura nivea. With the aid of macro- and micro-morphological characters and phylogenetic evidence based on 3-gene datasets, a comprehensive reassessment of generic boundaries within these taxa was conducted. Upon reviewing the systematic position of the taxa included, the three genera emerged as a well-defined monophyletic clade. Based on the genetic divergence observed, coupled with the robust support for monophyly, similarities in ecological roles, and congruence in macro- and micromorphological characteristics, we suggest a revised genus concept that synonymizes Irpicodon (as well as Plicaturopsis) with the earliest established genus Plicatura. [ABSTRACT FROM AUTHOR]

Up to 85% of shellfish reefs have been lost worldwide, resulting in declining ecosystem services, and increasing restoration demand. However, more information regarding the conditions which maximise oyster settlement and growth is required to optimise restoration. We deployed oyster settlement tiles at 21 intertidal sites throughout Moreton Bay, Australia; a region where > 96% of rock oyster reefs are lost and demand for restoration is high. We quantified effects of variables describing the spatial (from GIS), local habitat (using quadrats and water quality measures), and oyster predator (using underwater videography) characteristics of sites on oyster density and size on tiles. Oyster density was highest at sites with intermediate predator abundance and temperature, highest nearby invertebrate cover, and low and high values of turbidity and nearby rock and algae cover. Conversely, oyster size was highest at sites with intermediate predator density, higher fish species richness and turbidity, and lowest temperatures. Together, this showed that optimal restoration requires sites with 22 to 23 °C average water temperatures, between 10 and 15 oyster predators, and either low (< 2 NTU) or high (> 6 NTU) turbidity levels. Notably, we observed multiple peaks for several variables, suggesting the potential presence of multiple cryptic oyster species on settlement tiles. We found that oysters shared preferred environmental conditions with polychaetes, coralline algae, and tunicates, and were more prevalent and abundant at sites with lower turf algae, barnacle, and mussel cover. Identifying environmental variables influencing oyster population distribution, settlement, and growth can guide the selection and approach of oyster restoration sites. [ABSTRACT FROM AUTHOR]

Passeriformes are a sensitive group of birds that play a role as indicators of biodiversity, pollution, and environmental change. The military operations taking place in the Sumy region are the main threat to the region's biodiversity. Undoubtedly, the consequences of these threats can be reflected in a decrease in numbers, phenological changes, and changes in trophic interaction. However, due to their properties and ability to adapt, I assume that birds of the Passeriformes can respond to these environmental changes in different ways. Given the mosaic of different vegetation types and the presence of many transitional areas between them, the study area was divided into five habitats: household plots, pine forest, Vorsklytsia River, pastures, and agrocenoses. During the research period, 48 species of birds belonging to 18 families and 36 genera were identified. This study allowed us to confirm the hypothesis that similar species of birds are found in the three biotopes (pastures, agrocenoses, and household plots) and that most of them may have similar food resources in their diet. The results of grouping in the space of projections of the principal components, PC1 and PC2, taking into account the measured indicators of the number of representatives of the Passeriformes in relation to different habitats, showed a strong positive relationship between the number of bird species of the Passeriformes in pastures and agrocenoses, and the average relationship was determined for household plots and the Vorsklytsia River. A negative correlation was found for the pine forest, which shows a fairly high number of species as well as the originality of the habitat. The basis of the Passeriformes population was formed by sedentary birds. The highest proportion of sedentary species was found in household plots (31.3%) and the pine forest (31.3%). Dendrophiles were the most numerous group: in the pine forest, 95.2% (of all species), household plots, 66.7%, pastures, 50%, and Vorsklytsia River, 37.5%. Hollow-nested species had a high proportion of 57.1% in the pine forest, crown-nested species 46.7% also in the pine forest, shrubs 50% in household plots, and ground-shrubs 60% near the Vorsklytsia River. The highest proportion of species was found for entomophagous birds (30.3%) and polyphagous birds (31.4%) in the pine forest, while the phytophagous bird group had the highest proportion of 50% in the household plots. [ABSTRACT FROM AUTHOR]

Within the family Amylocorticiaceae , conspicuous morphological affinities exist among the previously defined species Irpicodon pendulus , Plicaturopsis crispa and Plicatura nivea . With the aid of macro- and micro-morphological characters and phylogenetic evidence based on 3-gene datasets, a comprehensive reassessment of generic boundaries within these taxa was conducted. Upon reviewing the systematic position of the taxa included, the three genera emerged as a well-defined monophyletic clade. Based on the genetic divergence observed, coupled with the robust support for monophyly, similarities in ecological roles, and congruence in macro- and micromorphological characteristics, we suggest a revised genus concept that synonymizes Irpicodon (as well as Plicaturopsis ) with the earliest established genus Plicatura .

Monitoring of sentinel species provides insight into the ecosystems in which they live. In the Southern Ocean, penguins are one such indicator species, where only a limited number of colonies have been monitored extensively for decades around Antarctica. As the Southern Ocean warms and commercial fishing continues, the need for expansion of population monitoring has become paramount. Using Adélie penguins (Pygoscelis adeliae) as a model species, we reviewed methods to estimate colony size including ground and aerial (occupied and unoccupied aircraft) assessment and satellite imagery, with an aim of understanding costs and benefits of each method to inform their future use. Ground assessment includes physically taxing field counts of individuals or nests and was historically the only method used to count penguins in Antarctica. Aerial assessments via occupied and unoccupied aircraft have expanded the spatial extent of monitoring for remote and logistically challenging environments such as Antarctica. Combined with aerial assessment, the more recent use of very high-resolution satellite imagery (VHR) has further expanded Adélie penguin monitoring into previously inaccessible areas. Adélie penguin breeding colonies can be monitored using VHR imagery through the area of their guano stain as a proxy for the number of breeding pairs. Our review provides an overview of the monitoring techniques for Adélie penguins in Antarctica and provides direction for future use and development. [ABSTRACT FROM AUTHOR]

Insects have been used as indicators of the state of environmental quality due to their ecological characteristics and role at many different trophic levels. In parcticular, moths are used as indicators to monitor the recovery of vegetation following environmental stress or as early warnings to measure the effects of environmental change at a local scale. For this type of evaluation, timed series of catch data from the same areas are of fundamental importance as reference data. Here we report the results of a year of sampling in areas of the Lucchese Apennines in Tuscany, Italy. These sites were previously sampled in the late 1970s. The results of this annotated list of species show a decrease in the number of species present in the study area that is not compensated by new records not sampled in the past.

In 2011, Korea installed artificial structures on four rivers to secure water resources and reduce flood damage; however, these structures have altered ecosystems and aquatic communities. This study analyzed fish communities and environmental variables at 72 sites in the Geumgang River. Fish communities and environmental variables before weir installation were examined using site data from 2008 to 2009. The results showed that Cyprinidae dominated the 70 observed species. A self-organizing map categorized the 72 sites into four groups based on fish communities. Sensitive and insectivorous species decreased, whereas tolerant and omnivorous species increased from Groups I to IV. Twenty-one indicator species were identified, with fewer and less distinct distribution patterns in Groups II and III than in Groups I and IV. The fish assessment index (FAI) showed a decline in grades A and B and an increase in grades C and D from Groups I to IV. Correlation analysis between the FAI and environmental variables indicated that fish communities in the Geumgang River were mainly influenced by water quality, reflecting altitude gradients and pollution levels. This study's findings are anticipated to significantly inform water management strategies for the Geumgang, Yeongsangang, Nakdonggang, and Hangang Rivers. [ABSTRACT FROM AUTHOR]

Yuanjiang dry–hot valley is located in the southwest of mainland China. It is a sparsely vegetated area with a fragile arid ecosystem. Although the valley previously had forest cover, it has become a tropical montane savannah in recent decades. Mechanisms controlling plant species distribution in such dry–hot valleys are unclear. Clarifying this will be beneficial to sustainable ecosystem management in dry–hot valleys. This study explored the relationship between diversity patterns of plant species and their environments in the lowland of this dry–hot valley. To achieve this, transects and plots were arranged along the river channel. Alpha and beta diversity indices were calculated to quantify biodiversity changes between species and environments. Estimated species, rarity, and abundance indices were also utilized to examine the correlation among species, their population size, and their environment: Species_estimated (expected number of species in t pooled plots), Singletons (the number of species with only one individual in t pooled plots), Uniques (the number of species living in one plot in t pooled plots), ACE (species richness estimator with coverage-based abundance), ICE (species richness estimator with coverage-based incidence), and Chao2 (species richness estimator extrapolated from Singletons). Fifty years of meteorological records, including temperature and precipitation, were utilized as climate variables. The results indicated the following findings: (1) alpha diversity was higher closer to the river, whereas the beta diversity was higher towards the lower sections of the river (Bray–Curtis < 0.5), but this trend was reversed in the perpendicular transects; (2) total phosphorous (TP) and total potassium (TK) were higher on flatter ground, tending to be associated with raised nitrogen (TN) and organic matter (OM); (3) soil nutrients were higher towards the lower sections of the river, corresponding to an increased number of species; (4) water supply determined plant distribution, with soil condition determining water retention; (5) the estimated species and their rarity and abundance indices were associated with proximity to the river, indicating heterogeneity of habitats and soil condition; and (6) fern species could be used as indicators representing the xeric environment of Yuanjiang dry–hot valley. Plant cover was reduced at low altitudes, with high temperatures and a low water supply. These results draw attention to the need for specific policy formation to protect the microhabitats and manage the environment of the Yuanjiang valley. [ABSTRACT FROM AUTHOR]

Floodplain forests are among the most endangered ecosystems worldwide, even though they are hotspots for numerous taxa. The abandonment of traditional management and large‐scale timber extraction, such as clear‐cutting, has led to a decline in floodplain forest biodiversity. Retention forestry has the potential to facilitate the implementation of an ecologically sustainable forest management approach. Despite the increasing popularity of this method, its potential for spider diversity conservation, especially its comparison with the widespread practice of clear‐cutting, is still poorly studied.We studied the short‐term effect of forestry treatments (dispersed retention with 60% retained trees and clear‐cutting) on the diversity of ground‐dwelling spiders in the floodplain forests along the Lower Morava (March) and Dyje (Thaya) rivers in the Czech Republic. Spiders were sampled using pitfall traps during 2021 (pre‐harvest year) and 2022 (post‐harvest year).A total of 10,005 specimens from 167 species were recorded. Both forestry treatments simplified habitat structure compared with pre‐harvest conditions, resulting in lower beta‐diversity within sites. However, dispersed retention had higher alpha‐ and beta‐diversity than clear‐cuts, indicating that retention provided a more complex‐structured habitat. Dispersed retention and clear‐cuts hosted distinct spider assemblages with characteristic indicator species. Species typical of open and significantly disturbed habitats preferred clear‐cuts, while species typical of forests and (semi‐) open habitats, including threatened species, showed a preference for dispersed retention.Our results demonstrated, for the first time, that dispersed retention forestry could serve as an effective management tool for conserving the ground‐dwelling assemblages of spiders in floodplain forests. [ABSTRACT FROM AUTHOR]

Human activity is one of the major causes of biodiversity loss in both plants and animals, as it can disrupt biological interactions and jeopardise the balance of ecosystems. Despite the implementation of conservation and environmental care policies, their management requires long-term monitoring and incurs high costs. In search of efficient solutions, bioindicator species have been implemented as cost-effective and time-efficient alternatives. Given their diverse roles within terrestrial ecosystems, ants serve as an ideal model group for assessing environmental health and changes in biodiversity. In this study, we focused on identifying disturbance-indicator ant species in various regions of Mexico and analysed their potential geographic distribution patterns. Information was gathered from various sources, including databases, entomological collections, and scientific articles. The human footprint was utilised to categorise ant species based on their impact in Mexico. Using the indicator species value (IndVal) method, 21 ant species indicatives of disturbance were determined across eight Mexican provinces. Eleven of these species exhibited widespread distributions, primarily in vegetation-deprived areas and human settlements. The presence of invasive exotic species, such as Paratrechina longicornis and Wasmannia auropunctata, underscores the need to assess their risks, identify invasion patterns, and develop control and conservation strategies. We provide a list of ecologically relevant ant species in Mexico, establishing a baseline for proposing conservation and effective biodiversity management strategies. [ABSTRACT FROM AUTHOR]

The Brazilian Atlantic Forest (BAF) is one of the most important biodiversity hotspots and species-rich ecosystems globally. Due to human activities, it has been significantly reduced and fragmented. This study examined both biotic (floristic composition, diversity, and structure) and abiotic (topographic and soil) factors in BAF fragments undergoing varying levels and durations of human disturbance cessation: approximately 20 years (20 y), ~30 years (30 y), and over 40 years (>40 y). We aimed to understand the recovery dynamics of floristic composition, diversity, and structure in BAF fragments in relation to abiotic factors. Several statistical tools were employed to examine similarities/differences and relationships. Forests of the 30 y group exhibit significantly greater homogeneity in terms of floristic composition, while forests of the 20 y group are characterized by lower species abundance and diversity. The floristic composition was primarily influenced by soil features and the time of disturbance. Under "Environmental Protection Areas", soil–vegetation recovery can occur more swiftly than usually observed for BAF. A significant BAF recovery was observed approximately 40 years after the end of human disturbance. A partial recovery featured 30 y disturbed areas, while in 20 y forests, recovery is in its early stages. Human-disturbed BAF can gradually rebound when effective management practices are implemented. [ABSTRACT FROM AUTHOR]

Previous research has demonstrated the value of the spirlin (Alburnoides bipunctatus), a small freshwater fish, as an indicator species for monitoring the ecological health of European rivers. In this study, we examine the temporal occurrence of spirlin in a lowland section of the River Drzewiczka, Poland, at the centre of the European distribution of the species. Using a mixed modelling approach, we show a significant interaction of freshwater fish species richness and time period on the probability of occurrence of spirlin across multiple microhabitats, with a strong positive relationship between the probability of occurrence and species richness at the end of the 20th Century, but an erosion in this relationship two decades later. This change in the predicted relationship of spirlin occurrence with freshwater fish species richness corresponds with a temporal decline in the water level of the River Drzewiczka. We discuss these findings in the context of the spirlin as an indicator species of the biotic integrity of European river environments. [ABSTRACT FROM AUTHOR]

The influence of seasonal paddy farming activities on the paddy field environment and its composition of birds could be visually observed but has yet to be systematically studied and is still relatively understudied in Malaysian Borneo. Earlier research relied solely on point counts and the failure to use line transects or mist nets for data collection could have resulted in missing and biased findings. Thus, this study aims to evaluate species diversity and evenness of birds in different paddy stages in southwestern Sarawak and compare the data with the findings of previous studies conducted in the region. We obtained higher species richness than previous reports from similar habitats, with 2552 individuals recorded from 94 species of 43 families. Of these, 75.53% and 24.47% were terrestrial birds and waterbirds, respectively. Seven resident taxa are listed as "Near Threatened" or "Vulnerable" according to the 2016-2022 IUCN Red List. The families of Ardeidae and Nectariniidae were most abundant with eight and six species, respectively. The planting and land preparation stages accommodated more diverse and even bird communities in the paddy fields of southwestern Sarawak. Our findings suggest that temporary land-use changes do not necessarily alter paddy field bird diversity and assemblages. Small-patch paddy fields should not be overlooked because they offer additional foraging niches for water-dependent birds and opportunistic feeders, as well as serving as a refuge for migratory waterbirds and vulnerable residents considering their habitat heterogeneity and microhabitat transitions between paddy stages. [ABSTRACT FROM AUTHOR]

Monitoring wild fish health and exposure effects in impacted rivers and streams with differing land use has become a valuable research tool. Smallmouth bass (Micropterus dolomieu) are a sensitive, indicator species that exhibit signs of immunosuppression and endocrine disruption in response to water quality changes and contaminant exposure. To determine the impact of agriculture and development on smallmouth bass health, two sites (a developed/agriculture site and a forested site) in the Susquehanna River watershed, Pennsylvania were selected where bass and water chemistry were sampled from 2015 to 2019. Smallmouth bass were sampled for histopathology to assess parasite and macrophage aggregate density in the liver and spleen, condition factor (Ktl), hepatic gene transcript abundance, hepatosomatic index (HSI), and a health assessment index (HAI). Land use at the developed/agriculture site included greater pesticide application rates and phytoestrogen crop cover and more detections and higher concentrations of pesticides, wastewater-associated contaminants, hormones, phytoestrogens, and mycotoxins than at the forested site. Additionally, at the developed/agriculture site, indicators of molecular changes, including oxidative stress, immune/inflammation, and lipid metabolism-related hepatic gene transcripts, were associated with more contaminants and land use variables. At both sites, there were multiple associations of contaminants with liver and/or spleen macrophage aggregate density, indicating that changes at the molecular level seemed to be a better indicator of exposures unique to each site. The findings illustrate the importance of timing for land management practices, the complex mixtures aquatic animals are exposed to, and the temporal changes in contaminant concentration. Agricultural practices that affect hepatic gene transcripts associated with immune function and disease resistance were demonstrated which could negatively affect smallmouth bass populations. [ABSTRACT FROM AUTHOR]

Simple Summary: This study is a first attempt to address the critical issue of effect of elevation on the distribution and body size of carabid beetles in the same region, including mountainous forests and the alpine tundra of the upper limit of vegetation in the north cold temperate zone. The richness, abundance and body size of carabid beetles linearly decrease with elevation increase. The larger carabid species C. canaliculatus and C. venustus become smaller to adapt to high-elevation tundra conditions. The vegetation type changes at high elevations is an important factor that leads to changes of carabid distribution and body size along the elevation gradient. These high-elevation species such as C. macleayi, N. pektusanica and P. jaechi should be given priority attention in the context of global climate change. The environment of mountain ecosystems can change greatly in short distances as elevation increases. The effects of elevation change on the distribution and body size of carabid beetles were investigated at elevations of 750–2600 m in the Changbaishan Nature Reserve (Northeast China). The richness and abundance of carabid species decreased significantly as elevation increased. However, the change trends are different in forests and tundra. In the broad-leaved Korean pine forest and coniferous forest at low elevations, carabid beetle species have high richness and abundance. The community composition of carabid beetles was significantly different at different elevations and among different vegetation types. Some species only occurred at specific elevations. There were fewer indicator species in high-elevation areas, but Carabus macleayi Dejean, Nebria pektusanica Horratovich and Pterostichus jaechi Kirschenhofer were mainly found in high-elevation areas. The average body size of species in the carabid beetle community was negatively correlated with elevation. The sizes of the larger Carabus canaliculatus Adams and Carabus venustus Morawitz were negatively correlated with elevation. Their body sizes decreased obviously in the tundra at elevations above 2000 m. Changes in vegetation types at high elevations affect the distribution and body sizes of beetles along the elevation gradient. Some large carabid species may be smaller at high elevations where a unique insect fauna has developed. The body size and distribution range of the carabid may be the factors that affect body size reduction at high elevation. Although some high-elevation species also occur in low-elevation areas, the protection of species diversity in high-elevation areas should be emphasized in the context of global climate change. The results illustrate the mechanisms of carabid beetles' response to elevation change and the need for carabid beetles' diversity conservation under global climate change. [ABSTRACT FROM AUTHOR]

Declines in amphibian populations have led to greater research and monitoring of species of interest, including terrestrial salamanders. Several methods have been used to study salamanders, including artificial cover objects (ACOs). Artificial cover objects are easy to install and use, limit destruction to habitats, are easily reproducible both across and within studies, and can reduce variability between observers and sites by not relying on observer search time or effort, or on natural cover. However, different ACO designs and spacing may yield different capture rates, and thus different estimates of population densities. We examined the influence of ACO wood type, size, shape, and spacing arrays on the number of individually marked red‐backed salamanders (Plethodon cinereus) captured under ACOs. White pine (Pinus strobus) ACOs yielded the most (average of 14 across 3 replicates) individuals, while white ash (Fraxinus americana) ACOs had the least (average of 7 across 3 replicates). Larger ACOs had similar capture rates compared to equal sampled areas of smaller ACOs, but a single smaller ACO tended to have fewer individual salamander captures than a single large ACO. Our results suggested that high‐density ACO spacing arrays may increase capture probability but reduce the area uniquely sampled by each ACO. In contrast, low‐density ACO arrays may produce population estimates more comparable to other arrays. Future studies should consider monitoring goals and available sampling effort when choosing a spacing array. As ACO study design impacts salamander capture rates, a clear understanding of the effects of each element of ACO design is important when drawing inferences or making comparisons among studies. [ABSTRACT FROM AUTHOR]

Aims: Knowledge about species niches along environmental gradients is needed to understand community assembly and spatial variation in floristic composition and species richness. In Amazonian rainforests, such knowledge is largely lacking, although ferns have been used to infer overall floristic and edaphic patterns. Here we explore fern species distributions along an important edaphic gradient, how narrow their realised niches are and how sensitive inferences are to species commonness, data quality and the region being sampled. Location: Amazonia. Methods: We used a large data set (1,215 transects across lowland Amazonia) to explore the realised niches of 54 species of two fern genera (Adiantum and Lindsaea) along a soil base cation concentration gradient. We used weighted averaging to estimate species optima and niche widths, and Huisman–Olff–Fresco modelling to assess species response shapes. Results: Overall, species optima were rather evenly spread along the soil base cation concentration gradient, but Lindsaea optima were limited to the lower half of the gradient, whereas Adiantum optima were more often in the upper half. Most species had unimodal response curves. Mean niche width was ca. 25% of the observed gradient length for Adiantum and 17% for Lindsaea and was only weakly or not at all related to different aspects of species commonness. Species optima were robust to different modelling approaches and consistent across regional subsets. However, the central Amazonian data contained no transects with high soil base cation concentration, so species with high optima were either absent or obtained a lower optimum than in the NW and SW regions. Conclusions: Our results support niche‐related species sorting as an important process that defines species co‐occurrence, turnover and richness patterns within Amazonian rainforests. All Adiantum and Lindsaea species, including the most abundant ones, had narrow enough realised niches to be considered useful indicators of edaphic and floristic variation within the rainforest. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we investigated differences in the non-fish diet components of the Grey Heron (Ardea cinerea) at both regional and local scales. We found significant inter-regional and inter-colony differences, not only in the diet but also in the habitat composition of foraging areas. We also identified significant relationships between some prey items and different habitats. This study shows that the opportunistic character of the diet of the Grey Heron is adapted to the local foraging habitat and the availability of non-fish prey. Habitat structure on foraging ground is one of the crucial factors determining diet diversity in colonially breeding avian predators. Quantifying the habitat and diet composition at different spatial scales (regional and local inter-colonial) can help provide understanding of the drivers of diet composition. In this study, we examined the composition of the non-fish diet of an opportunistic predator, the Grey Heron (Ardea cinerea), based on pellets. We compared pellets from 21 colonies in two different regions of Poland that differing in composition of foraging habitats. Multivariate statistical techniques were used to analyze the relationship between diet and habitat compositions in a 20 km radius around these colonies. Significant inter-regional and inter-colony differences in Grey Heron diet and habitat composition were detected in foraging areas. However, some prey were present in the diet only from one of the regions. Around the heronries with a predominance of farmland habitats, the European water vole (Arvicola amphibius) and terrestrial invertebrates were present in relatively low frequencies, and the striped field mouse (Apodemus agrarius) was present in high frequencies. Voles (Microtus sp.) were more frequent in colonies with prevalence of non-irrigated arable land around the colony, in contrast to the bank vole (Myodes glareolus), which was less common in heronries with a higher contribution of this habitat type. Remains of aquatic invertebrates were less abundant in colonies surrounded by extensive forests. The results of our research indicate the opportunistic character of the non-fish part of the diet of the Grey Heron adapted to the local foraging habitat and prey availability. [ABSTRACT FROM AUTHOR]

The influence of soil erodibility degree on the abundance and diversity of cultivated fungi and actinomycetes have been assessed for different seasons of the annual cycle. The objects of the study are sod-podzolic soils (Umbric Retisols (Abruptic)) with different erodibility degree, located on the slope of the southeastern exposure (Solnechnogorsk raion, Moscow oblast), which have been used for a long time for the cultivation of agricultural crops. The indicators of microbial abundance have been determined by the plate method, identification has been carried out on the basis of phenotypic characters. It is shown that the decline in physical and agrochemical parameters of the soil resulted from the erosion processes, leads to a change in microbiological parameters. An increase in the degree of soil erosion leads to a decrease in the abundance and species diversity of fungi and actinomycetes. Significant differences in the taxonomic composition of microbial communities of noneroded and eroded soils have been found (the Sørensen coefficient of species similarity does not exceed 0.42 and 0.30 for fungi and actinomycetes, respectively). Taxonomic units of mycelial microorganisms have been identified. Among fungi, they are represented by the species Aspergillus, Cladosporium, and Scopulariopsis, and among actinomycetes, by Streptomyces malachitospinus, S. candidus, and Micromonospora aurantiaca. [ABSTRACT FROM AUTHOR]

Tropical montane cloud forests (TMCF) are tropical vegetation that exhibits a great variety of specialized plant species due to the wide variation of abiotic factors, even along small distances. Climate, elevation, and other factors can also alter tree diversity and composition, such as geology, which was reported as the major determinant of differences between tree community structures growing in volcanic and limestone substrates. We assess how tree communities’ composition and diversity differ between fragments on limestone and volcanic substrates to corroborate a consistent spatial variation of forest composition and structure associated with geological substrates within tropical montane cloud forests. We registered 820 individuals of 64 species of temperate and tropical affinity. Sampling coverage was higher than 95%, and the most diverse indexes were registered to fragments on volcanic substrates. Four clusters were registered for species composition, with a high beta diversity and species turnover among sampled sites. The indicator species index varies between 0.54 to 0.88, being higher for Liquidambar styraciflua on volcanic substrate. Although substratum types can influence soil properties and determine differential species diversity, no evidence was found to corroborate that the tree community in tropical montane cloud forests is associated with a volcanic or limestone substrate. Tree community differences between and within sampled sites on volcanic and limestone substrates could be explained by the high species turnover due to the high tree heterogeneity of tropical montane cloud forests, forest recovery status, and disturbance. [ABSTRACT FROM AUTHOR]

Habitat disturbance driven by human activities poses a major threat to biodiversity and can disrupt ecological interactions. Butterfly–plant mutualisms represent an ideal model system to study such anthropogenic impacts, as butterflies exhibit intimate dependencies on larval host plants and adult nectar sources, rendering them highly sensitive to habitat changes affecting the availability of these floral resources. This study examined flower-visiting butterfly communities and their associations with flowering plants in a landscape altered by anthropogenic factors in central Mexico. The study area encompassed a mosaic of vegetation types, including native juniper forests, agricultural lands, and introduced eucalyptus plantations, representing different degrees of human-induced habitat modification. Monthly surveys were conducted over a single year, covering both rainy and dry seasons, to analyze butterfly and plant diversity, community composition, and interactions. Results showed the highest diversity in juniper forests, followed by eucalyptus and agricultural sites. Seasonal turnover was the primary driver of community changes, with habitat-based segregation persisting within seasons. Butterfly diversity strongly correlated with flower abundance, while plant richness played a secondary role. SIMPER and indicator species analyses identified key taxa contributing to compositional dissimilarities among habitats and associated with specific vegetation types and seasons. Our research provides insights into temporal dynamics structuring butterfly–plant interactions across this forest disturbance spectrum, highlighting how habitat changes and seasonality shape these mutualistic communities in changing landscapes. [ABSTRACT FROM AUTHOR]

The Nanhui-east-tidal-flat (NETF), the largest marginal shoal in the Yangtze River of China, is significantly impacted by human activities. Prior research has not detected the presence of green macroalgae in the NETF, nor has it explored the effects of reclamation on the distribution of macroalgae. However, in 2021, a small-scale aggregated attached algal mats emerged in the NETF, potentially signaling the onset of a green tide and necessitating vigilant monitoring. Morphological and molecular biological identification analysis revealed that all collected green macroalgae were attributed to a single dominant species, Ulva prolifera, characterized by broad blades and prominent air bladders, colonizing various substrates. The attached U. prolifera exhibited continuous growth from March to May 2021, peaking at a wet weight of 373.6229 g/m² and a dry weight of 72.7904 g/m² on May 1, 2021, within the accessible sampling period. The rapid proliferation of the “opportunistic” Ulva was facilitated by high-level eutrophication and favorable environmental conditions. Furthermore, six potential germplasm sources of U. prolifera are summarized. The dominance of Ulva in the intertidal zone often indicates high eutrophication and deteriorating ecological conditions. With long-term reclamation and repeated ecological restoration projects, the intertidal vegetation is subjected to a vicious cycle of growth and destruction. Therefore, it is important to recognize that U. prolifera germplasm (macroalgae and micropropagules) will persist over the long term, and mudflats with monotonous and eutrophic habitats are highly likely to experience future large-scale algal blooms. Notably, a small-scale floating green tide was observed in the sea area near NETF in July 2023, and such concerns are not unfounded. This study conducts foundational scientific research on the attached green tide algae, a type of research that is relatively scarce in other marine areas. Most studies tend to initiate foundational research only after the outbreak of green tides, lacking early background data from the marine environment, thus rendering this study of significant reference value. Concurrently, this study emphasizes that field surveys remain an essential approach for conducting foundational scientific research on green tide algae in the NETF region, with the need to select appropriate research methods based on the occurrence and development of algal mats, as required by the situation. Importantly, this study reflects the stability of marine ecosystems as a prerequisite for modern ocean management and services, provides new perspectives on the occurrence and development of green tides, and highlights potential ecological risk factors that should be considered in the implementation of intertidal construction projects.

Discharge regulation in rivers with cascade weirs profoundly alters natural flow dynamics, impacting habitat characteristics and leading to the homogenization of community structure and function. Identifying indicator species and their ecological thresholds is crucial for effectively monitoring and assessing the ecological conditions of regulated river systems. It is also essential for guiding conservation and management efforts. In this study, we investigated the influence of discharge patterns on zooplankton communities in the Yeongsan River, specifically focusing on the effects of flow regulation by cascade weirs. We analyzed the zooplankton community dynamics over a 12-year monitoring period and demonstrated the significance of discharge in shaping river ecosystem dynamics. Species indicator tests and gradient forest modeling were used to identify indicative genera and establish their ecological thresholds under various discharge patterns. Our findings revealed a distinct and significant discharge effect on zooplankton community composition and diversity, independent of water quality and nutrient-related factors. Monsoonal rainfall influenced the discharge patterns, which were categorized into three levels; this classification was further supported by indicator species and their responses. Despite their low abundances limiting clear responses, indicator genera, such as Rotaria and Macrothrix, were shaped by discharge levels. This study highlighted the need to incorporate discharge considerations into river management and conservation strategies to safeguard aquatic biodiversity. Our study provides valuable insights into sustainable river ecosystem management by elucidating the ecological consequences of flow regulation by cascade weirs.