Trophic Level Research Papers - Academia.edu (original) (raw)

2025, E3S web of conferences

Jatibarang reservoir serves as water supply in dry season and controlling flood in Semarang City. This reservoir is stem Kreo River which cathment areas of 54 km 2 , pool of area 110 ha and volume is 20 billion m3. This reservoir is potential to develop as natural fisheries area. The goals of this research were to explore existing condition of physical, biological as well as chemical parameter; carrying capacity assessment for natural fisheries; determining appropriate fish species to be developed in Jatibarang reservoir. This research was done in descriptive explorative scheme. Field survey and laboratory analyses were conducted to identify physical, chemical and biological parameters of the water. Physical parameters measured were temperature and water brightness. Chemical parameters measured were pH, DO, phosphate, Ammonia, nitrites and nitrate, while biological parameter measured were chlorophyll-a concentration. Carrying capacity analyses was done referred to the Government Regulation Number 82, 2001 that regulate the management of water quality and water pollution control. Based on the research, it showed that the existing condition of physical, chemical and biological parameters were still good to be used for natural fisheries. Based on TSI index, it classified as eutrofic water. Furthermore, tilapia fish (Oreochromis mossambicus), nile tilapia (Oreochromis niloticus) tawes (Barbonymus gonionotus) and carper fish (Cyprinus carpio) were considered as best species for natural fisheries in Jatibarang Reservoir.

2025, Journal of environment and ecology

Silvofishery application in Semarang was expected to provide several advantages for aquaculture activity, such as its support to the availability of natural food for Tilapia. This research aimed to analyze the suitability of Tilapia fish stomach content and the composition of plankton in the silvofishery pond in Semarang. Data collection included plankton abundance in A. marina and R. mucronata silvofishery plot and stomach content of Tilapia fish. Data were collected through field sampling occupying 6 silvofishery plot (3 for each vegetation type) and 6 fish samples (3 from each vegetation types). Water sampling was conducted by filtering 10 litres of water to 100 ml. Plankton identification was conducted in the laboratory. The result showed there were 7 plankton species found in the stomach content of Tilapia fish. Six similar species were found in the A. marina pond and only 5 similar species were found in R. mucronata pond. There was no similarity on the community structure of plankton found in the A. marina pond, R. mucronata pond and stomach content of Tilapia fish. The plankton abundance of A. marina plot was higher than the plankton abundance of R. mucronata plot.

2025, Management of Aquatic Resources Journal

Pencemaran air adalah masuknya atau dimasukkannya suatu zat, energi kedalam air oleh kegiatan manusia sehingga kualitas air dapat menurun sampai tingkat tertentu yang mengakibatkan air tidak dapat berfungsi sesuai dengan peruntukannya. Waduk Jatibarang merupakan bendungan yang menampung beberapa aliran sungai yang kemudian menjadi sarana dan prasarana akuatik dan mendukung kegiatan pariwisata yang ada. Masuknya air dari beberapa sungai ke dalam waduk dapat membawa bahan pencemar sehingga dapat mengakibatkan perairan waduk menjadi tercemar. Salah satu indikator penting dalam penentuan kualitas air adalah dengan melihat tingkat saprobitas di perairan. Berdasarkan hal tersebut maka perlu dikaji lebih lanjut mengenai kondisi kualitas perairan Waduk Jatibarang ditinjau dari aspek saprobitas. Tujuan dari penelitian ini adalah untuk mengetahui tingkat saprobitas perairan Waduk Jatibarang. Penelitian ini dilaksanakan pada bulan Mei -Juni 2017. Penelitian ini menggunakan metode studi kasus dengan analisis deskriptif dan analisis korelasi, dengan mengukur parameter pendukung yaitu parameter fisika, kimia, indeks biologi, dan indeks saprobitas. Hasil pengamatan menunjukkan bahwa nilai kelimpahan fitoplankton berkisar antara 236-865 ind/l, indeks keanekaragaman berkisar antara 1.02-1.77 indeks keseragaman berkisar antara 0.58-0.85 dan indeks dominasi berkisar antara 0.14-0.96. Indeks Kualitas Air (IKA) yang didapatkan berkisar antara 51.74-55.06 sehingga kualitas perairan dalam kategori sedang. Berdasarkan hasil penelitian didapatkan bahwa nilai indeks saprobitas berkisar antara 0.60-2.75 dan nilai indeks tropik saprobik berkisar antara 2.02-4.06 sehingga dapat disimpulkan bahwa perairan Waduk Jatibarang termasuk dalam golongan β-mesosaprobik/ oligosaprobik atau tercemar ringan.

2025

The marble trout Salmo marmoratus has been analyzed in a section of the Brenta River, where its populations show constant decrease despite many restocking operations carried out in the area. The study was carried out from October 2016 to December 2017 within three stream stretches placed from the border between Veneto and Trentino Alto Adige regions to the area near the Cismon del Grappa town. Analyses regarded fish communities, habitat availability for Salmo marmoratus, ecological status, fluvial functionality and chemical-physical features. Results highlighted several critical issues for the presence of well-structured marble trout populations, such as hybridization with brown trout Salmo trutta, habitat alteration and water pollution. Within the investigated area, pure Salmo marmoratus specimens (frequencies equal to 4-25%) and hybrids with Salmo trutta (5-27%) were observed. Brown trout was largely present in the area (8-60%). Available habitat ranged from 0 to 21% of the river ...

2025, Arkivoc

HPLC analysis of olanzapine 1, a known anti-psychotic drug, showed impurity peaks ranging from 0.05 to 0.15 % during process development. These samples were analyzed by LCMS and the peaks were identified at m/z 230, 341, 511, 326, 361 and 329. All six impurities were synthesized individually and characterized based on their spectral data (IR, NMR and Mass). The structure of these impurities were assigned as 2-methyl-4,9-dihydro-3-thia-4,9diazabenzo -1,4piperazine 6, 2,4-dimethyl-10-(4-methylpiperazin-1-yl)-4H-3-thia-4,9-diazabenzo[f]azulene 7, 10-(4-chloromethyl-4-methylpiperazin-1-ylium)-2-methyl-4H-3-thia-4,9-diazabenzo[f]azulene chloride 8 and 2-methyl-10-(4-methyl-N-oxopiperazin-1-yl)-4H-3-thia-4,9-diazabenzo[f]azulene 9 respectively. The formation, synthesis and characterisation of the olanzapine impurities are discussed.

2025, Bionatura

We assessed the size variation of morphological traits in Bosmina freyi regarding changes in environmental variables, the biomass of invertebrate predators, and algal food availability in two depths of the photic zone, the riverine zone, and near the dam zone (lacustrine zone) in The Riogrande II reservoir. In 200 individuals of B. freyi, using the software TpsDig2 we measured the body size, mucron and antennule lengths, and the antennule aperture percentage. Using the Mann-Whitney U test, we assessed the differences between these traits considering the zones and the photic depths; however, we used a canonical discriminant analysis with morphologic traits and environmental variables. Measured morphological traits showed a heterogeneous distribution between sampled zones and depths (p < 0.05). The highest values mucron and antennule lengths and the smallest antennule aperture angle were observed on small body size individuals, associated with physical, chemical, and biological cha...

2025, Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales

escalas espacial (longitudinal -vertical) y temporal en función de los gradientes de estado trófico, de biomasa algal y de la precipitación. Los cladóceros dominaron la biomasa, debido a la alta contribución de Bosmina freyi, seguidos de los copépodos y rotíferos. La biomasa de especies de microcrustáceos se asoció a la estación de muestreo eutrófica y de mayor biomasa algal, mientras que la biomasa de especies de rotíferos estuvo ligada a las estaciones de menor estado trófico. La mayor biomasa de microcrustáceos fue en la temporada de mayor estado trófico y la de rotíferos en la de mayor precipitación. En el gradiente vertical, la menor biomasa de todos los grupos fue en subsuperficie, zona que tendió a ser evitada por la mayoría de especies, durante los periodos de muestreo. La expresión de biomasa zooplanctónica en el eje longitudinal y en la escala temporal, respondió principalmente al gradiente de estado trófico y de biomasa algal, y en el eje vertical posiblemente a depredación. Aunque esta respuesta no dependió del hábito trófico de las especies, probablemente por la oferta trófica diversa del embalse y por la plasticidad alimenticia de las especies, sí fue diferente entre microcrustáceos y rotíferos. Palabras clave: rotíferos, microcrustáceos, biomasa, estado trófico, Bosmina freyi. Response of the zooplankton biomass to the gradient of trophic status, and rainfall of a tropical reservoir

2025, Actualidades Biologicas

con diferentes estados tróficos, durante los periodos de alta y baja precipitación. Además, se analizó su relación con las variables temperatura, oxígeno disuelto, pH, transparencia, nutrientes y con la biomasa fitoplanctónica. La biomasa de rotíferos fue dominada por Asplanchna girodi De Geurne 1888, en los dos embalses y fue significativamente mayor en el embalse de menor trofía. Aunque la biomasa de rotíferos no mostró un gradiente longitudinal significativo, sí presentó zonación vertical dentro de la zona fótica, con mayor biomasa en el 10 y 1% de incidencia lumínica. Los patrones de variación de la biomasa total de rotíferos y de las especies dominantes estuvieron determinados principalmente por el ingreso de sólidos suspendidos en el embalse de mayor trofía y por la biomasa y la densidad del fitoplancton en el embalse con menos nutrientes. A diferencia de lo esperado, la biomasa de los rotíferos no fue favorecida por condiciones de mayor estado trófico, ya que el factor preponderante sobre la expresión de biomasa fue la calidad de los recursos alimenticios en cada embalse.

2025

With over 15,000 extant species, Decapoda—or ten-legged crustaceans such as crabs, shrimp, lobsters, and relatives— are among the most speciose and economically important group of crustaceans. Despite of their diversity, anatomical disparity, and remarkable fossil record extending back to the Late Paleozoic, the origins of Decapoda and their phylogenetic relationships with eumalacostracans remains elusive and inconclusive. Molecular dating suggests that decapods originated in the Late Ordovician (~450 Mya), but no reliable fossil crown groups are found until the Late Devonian. Moreover, there is no consensus on which lineages belong to stem groups, obscuring our understanding of the roots of the ten-legged decapod body plans as a whole, and how they relate to other non-decapod crustaceans. We present new, exceptional fossils from the Late Devonian of Czech Republic and Poland that belong to †Angustidontida, an odd shrimp-looking crustacean with a combination of anatomical features u...

2025, Water Research

Wetlands, especially marshes, support many services such as carbon catchment control or water purification led by primary producers such as phytoplankton and microphytobenthos (PB). The impact of the sedimentary compartment, as source and sink of essential nutrients for the water column, is often neglected in the study of their dynamics and water purification capacity of the systems. This work compared monthly (between February 2020 and April 2021) the benthic and pelagic primary producers' dynamics in two anthropised freshwater marshes (Marans and Genouillé), with the simultaneous follow-up of physico-chemical parameters of the water column and nutrient fluxes at the sediment-water (SWI) interface. It was suggested a strong contribution of phytoplankton (pumping) and the benthic compartment (denitrification) to the water purification of these two nitrates (NO 3 -)-rich marshes. Total phytoplankton production fluctuated between ~5 (winter) and 1500 mg C m -3 d -1 (fall) at Marans and between 40 (winter) and ~750 mg C m -3 d -1 (spring) at Genouillé. At Marans, soluble reactive phosphorus (SRP) benthic effluxes (-2.10 1 to -6.10 2 µmol m -2 d -1 in fall and summer respectively) coincided with phytoplankton bloom periods. These effluxes were inhibited by NO 3 -penetration in the sediment (0 to 5.10 4 µmol m -2 d -1 ), by inhibiting iron respiration. At Genouillé, inhibition of SRP effluxes depended on denitrification rate and on P stocks in the sediment, where slight SRP effluxes (-10 1 µmol m -2 d -1 ) could have co-occurred with slight NO 3 -influxes (5.10 2 µmol m -2 d -1 ) in spring. The presence of PB (between 10-60 and 40-120 mg g sed -1 at Marans and Genouillé respectively), suggested a strong contribution of the benthic compartment to the total primary production (benthic and pelagic through resuspension processes) in these environments. This work encourages to consider the benthos and the pelagos as a unicum to provide better sustainable management of such systems and limit eutrophication risks in coastal areas.

2025, Fisheries Science

An ecosystem model was constructed for the northern Bay of Bengal (nBoB) using Ecopath (version 6.4.4). The model covered an area of 18,500 km 2 . There were 32 functional groups in the model including the non-living group, detritus. Trophic levels (TLs) for individual groups ranged from 1.0 to 4.22. Ecotrophic efficiency for most of the small pelagic fishes was found to be greater than 0.7. For hilsa it was 0.853, indicating high exploitation of this fish within the system. The nBoB was estimated to be a low ascendancy area (~ 19.2%) with a system overhead of 80.8%, which indicates system stability and a certain maturity. The total system throughput and the total primary production/total respiration estimated for the study area indicate that nBoB is a maturing ecosystem. The mean TL of the catch for the study area was 3.115. The results indicate that the nBoB system is still in a developing stage. The low mean TL of the catch indicates fishing practices targeting fish of lower TLs in the system. In the long run, this may cause fishing down the food web, which will eventually lead to declining catches. These results indicate that present fishing practices are unsustainable for the nBoB ecosystem.

2025, Hydrobiologia

Fish and invertebrates are introduced in freshwaters around the world for commercial purposes, despite widely known impacts on food webs and biological invasions. As a proxy for artificial environments, we modeled a typical reservoir in a Brazilian semiarid region using an ecosystem approach. We compared the role of native and nonnative invasive species (NIS) in the food web, between dry and wet periods, and under the influence of an extreme drought period (from 2011 to 2015), simulating the variation in fish biomasses due to decreasing consumption. Key ecosystem groups were fishes (mainly NIS), birds, and insects. Nutrient cycling was dependent on invaders, while the trophic structure was detritus based during the drought. Biomass of detritivores was almost two times higher than herbivores, and native fish species decreased abruptly in response to invaders and volume variation. The dominance of low-trophic levels (TLII) and tilapia-Oreochromis niloticus (Linnaeus, 1758) and other tilapiines-resulted from interactions among invaders, feeding behavior on benthos, and environmental seasonality, tending toward biotic homogenization (''benthification'') at the ecosystem level. An increasing relevance of detritivores with cascading effects in ecosystems subject to drought, multiple

2025, Oecologia Australis

Aquatic ecosystems are under different anthropogenic pressures, such as climate change, eutrophication, chemical pollution, overfishing, and introducing exotic species. Human activities have accelerated biogeochemical cycles forcing organisms and ecosystems to adapt. Most ecological stoichiometry studies are focused on carbon, nitrogen, phosphorus, and their relative proportions. Still, the possibilities for investigations using other elements to better understand the impacts of human pressures on aquatic ecosystems are vast. Therefore, here we explore how different anthropogenic activities influence ecosystem balance in terms of nutrient composition and stoichiometry. We conclude that human interventions have affected the functioning of aquatic ecosystems in terms of energy flow due to stoichiometric imbalances. We also conclude that the interplay between macro and micronutrient stoichiometry might raise important axioms to predict and understand human impacts on the functioning of...

2025, Acta Limnologica Brasiliensia

2025, Science of The Total Environment

CO 2 supersaturation is prevalent in eutrophic low-latitude fresh waters • The pCO 2 was significantly higher in these lakes than at higher latitudes • Rainy season resulted in high pCO 2 in low-latitude freshwater systems • pCO 2 increased as eutrophication decreased with higher water volume • Land-use types directly affected trophic state but not water pCO 2

2025, Toxics

Plastic pollution in the oceans is a growing problem, with negative effects on exposed species and ecosystems. Xyrichtys novacula L. is a very important fish species both culturally and economically in the Balearic Islands. The aim of the present study was to detect and categorise the presence of microplastics (MPs) in the digestive tract of X. novacula, as well as the existence of oxidative stress in the liver. For this purpose, the fish were categorised into two groups based on the number of MPs observed in the digestive tracts: a group with no or low presence of MPs (0–3 items) and a group with a higher presence of MPs (4–28 items). MPs were found in 89% of the specimens analysed, with a dominance of fibre type and blue colour. Regarding the type of polymer, polycarbonate was the most abundant, followed by polypropylene and polyethylene. For the group with a greater presence of MPs, the activities of the antioxidant enzymes glutathione peroxidase and glutathione reductase, as wel...

2025

época seca del año 2008. En nueve arroyos intermitentes y nueve permanentes se colectaron muestras de macroinvertebrados y parámetros ambientales. A traves de análisis multivariados, se determinaron relaciones entre variables biológicas (según riqueza, abundancia, composición trófica y rasgos biológicos) con las variables ambientales. La estacionalidad no tuvo efecto significativo sobre la riqueza ni densidad de macroinvertebrados, tampoco se encontraron efectos notorios sobre la composición trófica ni los rasgos biológicos (tipo de respiración), pero sí encontramos diferencias significativas en la composición taxonómica, especialmente en la proporción de Ephemeroptera, Plecoptera y Trichoptera (EPT); asimismo, encontramos que existen otras variables ambientales como la profundidad, solidos disueltos y pH que tienen mayor efecto que la intermitencia en la riqueza y densidad total. De acuerdo a datos climáticos de la región Andina de Bolivia se sabe que en el futuro habrá una disminución del agua, incluso la desecación temporal en varios ríos de la zona, esto debido a la disminución de los glaciares. De esta manera, el futuro cambio climático reflejado a través de la estacionalidad de los ríos, tendrá mayor efecto en los cambios de la estructura taxonómica que en la estructura funcional, lo que indica que probablemente tendrá implicaciones más fuertes en la conservación de taxa que en la composición de los rasgos de la comunidad de macroinvertebrados. Palabras clave: insectos acuáticos, estacionalidad de ríos, glaciares andinos, Bolivia

2025, Environmental Science and Pollution Research

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

2025, FEMS Microbiology Ecology

Plants modulate the soil microbiota by root exudation assembling a complex rhizosphere microbiome with organisms spanning different trophic levels. Here, we assessed the diversity of bacterial, fungal and cercozoan communities in landraces and modern varieties of wheat. The dominant taxa within each group were the bacterial phyla Proteobacteria, Actinobacteria and Acidobacteria; the fungi phyla Ascomycota, Chytridiomycota and Basidiomycota; and the Cercozoa classes Sarcomonadea, Thecofilosea and Imbricatea. We showed that microbial networks of the wheat landraces formed a more intricate network topology than that of modern wheat cultivars, suggesting that breeding selection resulted in a reduced ability to recruit specific microbes in the rhizosphere. The high connectedness of certain cercozoan taxa to bacteria and fungi indicated trophic network hierarchies where certain predators gain predominance over others. Positive correlations between protists and bacteria in landraces were p...

2025, Environmental Entomology

2025, Mammalian Biology

There was a mistake in the legend of Figure , the correct legend is: Average values (individuals/m 2 ) with standard errors of the macroinvertebrate prey availability in the Catllar stream found during the seasonal samplings (spring, summer and autumn). Values include only the availability of the aquatic taxa consumed by the analysed vertebrate predators. The original article has been corrected.

2025, Mammalian Biology

Conservation of vulnerable species in headwater streams requires good knowledge of their resource use and how they interact with competitors. In this study, we characterised the macroinvertebrate community of a Pyrenean headwater stream and assessed how it was used as a food resource-above all, in terms of prey electivity and diet overlap-by three semi-aquatic insectivorous vertebrates (Galemys pyrenaicus, Neomys fodiens and Cinclus cinclus). With this information, we examined the diet specialisation of the vulnerable Pyrenean desman (G. pyrenaicus) in the stream and analysed its implications for its conservation. There was a clear dietary overlap between these three predators, which resulted in interspecific trophic competition. G. pyrenaicus tended to avoid terrestrial prey and focused on abundant and energetically profitable rheophile species, for which it is well adapted. This diet specialisation makes it vulnerable to any decrease in food availability resulting from anthropogenic stressors such as damming, which can reduce habitat quality and prey availability. More research is needed to fully understand prey electivity in G. pyrenaicus and so be able to suggest effective conservation measures for this species.

2025, Limnetica

Salmo trutta is a key species of headwater streams that is able to influence the structure of these ecosystems through predation. Populations of this species are being threatened by climate change and hydrological alteration. In order to understand how their disappearance would affect the ecosystem structure of headwater streams, we used cage experiments to analyse different biofilm and macroinvertebrate structural parameters and the biodiversity of their communities under different trout densities. Due to a heavy rain event, our experiment was destroyed on the 10 th day, but the role of trout as stream ecosystemic structure drivers was observed, as multiple parameters were modulated by their presence or absence. In the high-density treatments, a significant reduction in the biomass of macroinvertebrate families that fed on biofilms was observed due to direct predation on them, which caused the biofilms to be more autotrophic. A decrease in brown trout population densities could cause cascading trophic effects on the ecosystem structure of headwater streams.

2025, Limnetica

Salmo trutta is a key species of headwater streams that is able to influence the structure of these ecosystems through predation. Populations of this species are being threatened by climate change and hydrological alteration. In order to understand how their disappearance would affect the ecosystem structure of headwater streams, we used cage experiments to analyse different biofilm and macroinvertebrate structural parameters and the biodiversity of their communities under different trout densities. Due to a heavy rain event, our experiment was destroyed on the 10th day, but the role of trout as stream ecosystemic structure drivers was observed, as multiple parameters were modulated by their presence or absence. In the high-density treatments, a significant reduction in the biomass of macroinvertebrate families that fed on biofilms was observed due to direct predation on them, which caused the biofilms to be more autotrophic. A decrease in brown trout population densities could caus...

2025, Mammalian Biology

Conservation of vulnerable species in headwater streams requires good knowledge of their resource use and how they interact with competitors. In this study, we characterised the macroinvertebrate community of a Pyrenean headwater stream and assessed how it was used as a food resource—above all, in terms of prey electivity and diet overlap—by three semi-aquatic insectivorous vertebrates (Galemys pyrenaicus, Neomys fodiens and Cinclus cinclus). With this information, we examined the diet specialisation of the vulnerable Pyrenean desman (G. pyrenaicus) in the stream and analysed its implications for its conservation. There was a clear dietary overlap between these three predators, which resulted in interspecific trophic competition. G. pyrenaicus tended to avoid terrestrial prey and focused on abundant and energetically profitable rheophile species, for which it is well adapted. This diet specialisation makes it vulnerable to any decrease in food availability resulting from anthropogen...

2025

Lake Tanganyika’s pelagic fish sustain the second largest inland fishery in Africa and are under pressure from heavy fishing and global warming related increases in stratification. Only little is known about whether basin-scale hydrodynamics – including a more stratified north and an upwelling-driven south – induce ecological and genetic differences among populations of highly mobile, pelagic fish inhabiting these different areas. Here, we examine whether the basin-scale dynamics leave distinct isotopic imprints in the pelagic fish of Lake Tanganyika, which may reveal differences in habitat, diet, or lipid content. We conducted two lake-wide campaigns during different seasons and collected physical, nutrient, chlorophyll, phytoplankton and zooplankton data. Additionally, we analyzed the pelagic fish – the clupeids Stolothrissa tanganicae, Limnothrissa miodon and four Lates species – for their isotopic and elemental carbon (C) and nitrogen (N) compositions. The δ13C values were signi...

2025, E3S web of conferences

The objective of this study is to generate maps of coastal areas based on the Environmental Sensitivity Index (ESI) to assess oil spills risk. These maps have become a crucial tool for operational responders. ESI is a tool developed to evaluate the sensitivity of coastal environments and provides a method to assess the impact of oil spills systematically IPIECA. IMO. IOGP, (Juillet 2012). The establishment of the future Nador West Med oil transshipment port is expected to make maritime transport of hydrocarbons a significant source of pollution along the Eastern Region of Morocco (ERM), given the substantial traffic in these products. Through satellite imagery, it has been possible to observe and recognize the different geomorphological formations along the coast. In order to map these sites based on ESI index and describe their characteristics, it is essential to utilize Geographic Information System (GIS) and multi-criteria analysis methods to manage all relevant information. The produced maps provide valuable support to stakeholders in coastal management of oil spills response. Furthermore, ESI is used for coastal area management and preservation, particularly in identifying ecologically valuable regions. There are plans to implement a realtime alarm system to visualize coastal areas sensitivity in terms of the ESI index, guiding pollution control in the coastal areas.

2025, Chemosphere

Forest decline studies in Trentino and South Tyrol were initiated in the early 80's. In 1992 four permanent stalaens were selected under the ICP-IM programme of the UN-ECE. Based on an inter-disciplinary approach it is aimed to study pollution effects in relation to anthropogenic stress, climate change, trophic systems and trophic-energy balances of the ecosystem. The Integrated Monitoring programme has made progress in identif36ng bio-indicators that describe the system, which will also help in sylvieultural management. The programme also has various other topics under study. The results particularly highlight the effect of climate change over the last ten years.

2025, Frontiers in Marine Science

Although the relationship between biodiversity and ecological functioning is a vital issue in coastal water ecology, how this relationship is influenced by environmental conditions is still unknown. It was investigated for the dynamics of algal diversity and algal pollution indices, as well as their relationships with trophic state, in a mangrove forest along the Guangdong coast, South China. It is hypothesized that the phytoplankton alpha-diversity indices and algal pollution indices have the potential to provide a signal linking trophic state and water quality variation in the mangrove forest. The t-test showed that phytoplankton alpha-diversity indices and algal pollution indices varied significantly between the dry and wet seasons (p < 0.01 or p < 0.05). The trophic state index record confirmed that the mangrove forest was mesotrophic to eutrophic during study periods while the CCME: WQI revealed that the water quality in the forest was under poor and marginal conditions i...

2025, Frontiers in Marine Science

Many coastal areas host rich marine ecosystems and are also centers of economic activities, including fishing, shipping and recreation. Due to the socioeconomic and ecological importance of these areas, predicting relevant indicators of the ecosystem state on sub-seasonal to interannual timescales is gaining increasing attention. Depending on the application, forecasts may be sought for variables and indicators spanning physics (e.g., sea level, temperature, currents), chemistry (e.g., nutrients, oxygen, pH), and biology (from viruses to top predators). Many components of the marine ecosystem are known to be influenced by leading modes of climate variability, which provide a physical basis for predictability. However, prediction capabilities remain limited by the lack of a clear understanding of the physical and biological processes

2025

When humanity confronts the risk of extinction of species, many people invoke precautions, especially in the face of uncertainty. Although precautionary approaches are value judgments, the optimal design and effect of precautions or lack thereof are scientific questions. We investigated Wisconsin gray wolvesCanis lupusfacing a second wolf-hunt in November 2021 and use three legal thresholds as the societal value judgments about precautions: (1) the 1999 population goal, 350 wolves, (2) the threshold for statutory listing under the state threatened and endangered species act, 250 wolves; and (3) state extirpation <2 wolves. This allows us to explore the quantitative relationship between precaution and uncertainty. Working from estimates of the size wolf population in April 2021 and reproduction to November, we constructed a simple linear model with uninformative priors for the period April 2021-April 2022 including an uncertain wolf-hunt in November 2021. Our first result is that ...

2025, Frontiers in Marine Science

Marine mammals have been proposed as ecosystem sentinels due to their conspicuous nature, wide ranging distribution, and capacity to respond to changes in ecosystem structure and functioning. In southern European Atlantic waters, their response to climate variability has been little explored, partly because of the inherent difficulty of investigating higher trophic levels and long lifespan animals. Here, we analyzed spatio-temporal patterns from 1994 to 2018 of one of the most abundant cetaceans in the area, the common dolphin (Delphinus delphis), in order to (1) explore changes in its abundance and distribution, and (2) identify the underlying drivers. For that, we estimated the density of the species and the center of gravity of its distribution in the Bay of Biscay (BoB) and tested the effect of three sets of potential drivers (climate indices, oceanographic conditions, and prey biomasses) with a Vector Autoregressive Spatio Temporal (VAST) model that accounts for changes in samp...

2025, Oecologia

Invasive species can have major impacts on ecosystems, yet little work has addressed the combined effects of multiple invaders that exploit different habitats. Two common invaders in aquatic systems are pelagic fishes and crayfishes. Pelagic-oriented fish effects are typically strong on the pelagic food web, whereas crayfish effects are strong on the benthic food web. Thus, co-invasion may generate strong ecological responses in both habitats. We tested the effects of co-invasion on experimental pond ecosystems using two widespread invasive species, one pelagic (western mosquitofish) and one benthic (red swamp crayfish). As expected, mosquitofish had strong effects on the pelagic food web, reducing the abundance of Daphnia and causing a strong trophic cascade (increase in phytoplankton). Crayfish had strong effects on the benthic food web, reducing the abundance of benthic filamentous algae. Yet, we also found evidence for important cross-habitat effects. Mosquitofish treatments red...

2025

The Cochin estuarine system (CES) being one among the world’s highly polluted and productive estuarine system was monitored to assess the trophic condition in view of the changing nutrient regime. The estuarine system was shallow, with mixo-oligo to mixo-mesohaline salinities (9.65 ± 6.99 ‰). The dissolved oxygen and the pH regime of the water column were 5.92 ± 1.13 mg L and 7.42 ± 0.71, respectively. The study documents high dissolved inorganic nitrogen (28.95 ± 8.47 μmol L), dissolved inorganic carbon (1089.87 ± 362.36 μmol L), dissolved inorganic phosphate (7.76 ± 3.56 μmol L) and gross primary productivity (2.31 ± 1.14 gC m day). However, explicitly augmented inorganic nutrients coupled with low dissolved oxygen, pH, and productivity patterns were observed in station 7. High dissolved inorganic carbon denoted net heterotrophic condition. Trophic index (TRIX units) was observed to be high compared to earlier reports, indicated eutrophicated condition with the highest value at st...

2025, Regional Studies in Marine Science

• Anthropogenic activities have accelerated the nitrogen loading in the estuary. • Enriched nitrogen has led to higher nitrous oxide concentrations and emissions. • Thereby estuary significantly contributing to atmospheric nitrous oxide... more

2025, Trends in Ecology & Evolution

Understanding ecological processes and predicting long-term dynamics are ongoing challenges in ecology. To address these challenges, we suggest an approach combining mathematical analyses and Bayesian hierarchical statistical modeling with diverse data sources. Novel mathematical analysis of ecological dynamics permits a process-based understanding of conditions under which systems approach equilibrium, experience large oscillations, or persist in transient states. This understanding is improved by combining ecological models with empirical observations from a variety of sources. Bayesian hierarchical models explicitly couple process-based models and data, yielding probabilistic quantification of model parameters, system characteristics, and associated uncertainties. We outline relevant tools from dynamical analysis and hierarchical modeling and argue for their integration, demonstrating the value of this synthetic approach through a simple predator-prey example.

2025, Boletin de la …

Los principales ítems presa fueron: coleópteros, arañas y ácaros para L. ocellatus; dípteros, arañas, coleópteros, hemípteros y ácaros para H. p. pulchella; formícidos para B. gr. granulosus; y colémbolos, ácaros y formícidos para P. gracilis. Leptodactylus ocellatus e H. p. pulchella mostraron los valores más altos de amplitud trófica, P. gracilis ocupó una posición intermedia, y B. gr. granulosus presentó los valores más bajos. De acuerdo a las características de las presas consumidas, se propone una estrategia de forrageo de tipo sit-and-wait para L. ocellatus e H. p. pulchella, y una estrategia de tipo activa para B. gr. granulosus. El análisis de los cambios estacionales indicó que, salvo P. gracilis, las demás especies incrementaron la amplitud trófica durante la estación fría, principalmente por inclusión de nuevas presas por cada depredador. Este aumento, probablemente relacionado con un cambio en la oferta de presas, indicaría que las especies no ocupan lugares estancos sobre un continuo con extremos generalista y especialista.

2025, Oceanologica acta

The long-term variations of two coastal benthic communities (Eastern English Channel, France) were studied between 11979 and 1.994 by means of factor correspondence analysis (FCA), trophic structure and rank-frequency diagrams (RFD). FCA identified periods of relative homogeneity and periods of strong variation in the structure of the two communities. The first community, established on heterogeneous sand, showed a multi-annual cycle linked to grain-size variations in the sedimlent. As passive su.pplies of organic matter were not important and suspension feeders could hardly live in these conditions, the community remained poor and stable and was dominated by deposit-feeders and carnivores. The other one, a rich and diverse mussel (Mytilus edulis) bed, showed great variations in the abundance of the main species which generated thle enrichment of the community by its suspension-feeding behavilour (biodeposition). Beyond these variations, the community remained stable until 1990 as no continuous trend or permanent change could be seen. Since 1990, no recruitment of M. edulis occurred and the relative dominance of suspension feeders, as well as the number of species, strongly (decreased. During the following years, several species of tunicates (sessile suspension feeders with gregarious recruitment) recruited and partly took the ecological niche of M. edulis but they did not induce an increase of biodeposition and the previous richness was not restored. After a strong and rapid shift in the structure, a new equilibrium has been established within the community. 0 Elsevier, Paris long-term series / benthos I factor analysis / rank-frequency diagrams I trophic structure RCsumC -Variations B long terme (1979-1994) de deux peuplements ben.thiques &tiers (Manche orientale, France) : analyse de 1'6volution structurale. Les variations ti long terme de deux peuplements benthiques &tiers ont Ct& CtudiCes entre 1979 et 1994 au moyen d'analyses factorielles des correspondances (AFC), de 1'Ctude de la structure trophique et des diagrammes rang-frkquence. Les AFC ant mis en Cvidence des pCriodes relativement homogknes et des p6iodes de variations importantes pour les deux peuplements. Le premier peuplement, 6tabli sur des sables hCt&og&nes, montre une variation pluri-annuelle de sa structure fortement li6e SI celle de la granulomktrie du stdiment. Les apports de mat&e organique &ant assez faibles et les suspensivores &ant peu abondants dans ce type de peuplement, celui-ci reste pauvre, relativement stable et domint par les dCposivores et les carnivores. Le deuxikme peuplement, une moulibre AMytilus edulis, pr&ente de grandes variations de l'abondance relative de l'espbce principale M. edulis, 2 l'origine de l'enrichissement du peuplement et de la modification du skdiment par biodCposition. .Au-de12 de ces variations, la structure globale du peuplernent paraissait stable jusqu'en 1990, quand aucun recrutement de M. edulis n'a ttk constat& Aprbs cette an&e-l%, il semble qu'il n'y ait plus de recrutement de moules, ce qui s'est d'abord traduit par une baisse sensible du nombre d'espbces et de la dominance relative des suspensivores. Depuis, plusieurs espkces de Tuniciers (esphces sessiles suspensivores B recrutement grkgaire) occupent la niche de M. edulis, mais leur activitt suspensivore n'induit pas de bio-Oceanologica Acta (0399 1784/98/04/O Elsevier, Paris

2025, Journal of Sea Research

2025, Hydrobiologia

We studied the responses of a food web, especially fish and zooplankton, to summertime aeration, pumping of oxygen-rich epilimnetic water to the hypolimnion in Lake Vesijärvi, southern Finland. The aim of hypolimnetic aeration was to reduce internal loading of phosphorus from sediment. The population of smelt (Osmerus eperlanus L.), the main planktivore of the pelagial area, collapsed during the two 1st years of aeration due to increased temperature and low oxygen concentrations in the hypolimnion. The population recovered after the 4th year of hypolimnetic aeration, when oxygen conditions were improved. Despite elevated hypolimnetic temperature, smelt reached exceptionally high abundance, which led to a significant reduction in cladoceran body size. The density of perch (Perca fluviatilis L.) increased at first, but then decreased when the proportion of smelt and cyprinids increased. Biomasses of Daphnia decreased probably as a result of the disappearance of dark, low-oxygen deep-w...

2025, Scientific Reports

Ecological speciation – whereby an ancestral founder species diversifies to fill vacant niches – is a phenomenon characteristic of newly formed ecosystems. Despite such ubiquity, ecosystem-level effects of such divergence remain poorly understood. Here, we compared the trophic niche of European whitefish (Coregonus lavaretus) and their predators in a series of contrasting subarctic lakes where this species had either diversified into four ecomorphologically distinct morphs or instead formed monomorphic populations. We found that the trophic niche of whitefish was almost three times larger in the polymorphic than in the monomorphic lakes, due to an increase in intraspecific specialisation. This trophic niche expansion was mirrored in brown trout (Salmo trutta), a major predator of whitefish. This represents amongst the first evidence for ecological speciation directly altering the trophic niche of a predator. We suggest such mechanisms may be a common and important – though presently...

2025, Open Journal of Ecology

First record of a bloom of filamentous-heterocystous nitrogen fixer cyanobacterium, Aphanizomenon ovalisporum, was documented in the summer of 1994 in Lake Kinneret (Israel). Awareness of such a bloom outbreak was predicted earlier based on documentation of Nitrogen deficiency and Phosphorus Sufficiency developed conditions. The concept of Nitrogen fertilization aimed at suppression of Nitrogen fixers Cyanobacteria was worldwide discussed and successfully implemented, but mostly in temperate oligotrophic lake ecosystems. This paper presents an experimental testing of this concept by additional Nitrogen. The results of the present study did not verify this hypothesis probably related to the ecological differences between Kinneret and the temperate ecosystems and using only one factor (Nitrogen) to test it.

2025, Springer eBooks

Biomanipulation (as defined by Shapiro) and top-down or consumer controlled forces refer to the control of natural aquatic organisms to improve water quality instead of through nutrient management. A cornerstone of biomanipulation studies was established during the late fifties and early sixties when the effect of fish on water quality via zooplankton predation was shown. Biomanipulation through animals other than fish or zooplankton has also been noted. The classical limnological concept of lake trophodynamics goes from nutrients through phytoplankton to zooplankton and fish. Therefore, top-down forces as a potential tool for manipulation was seen as a pioneering approach. During the seventies, many studies on trophic cascading effects of fish through zooplankton predation on phytoplankton have been carried out. The removal of Macrophytes by grass carp has also been investigated and was implemented as a practical way of controlling these plants. During the eighties the concept of biomanipulation was broadened to include other aspects of the complex interactions between food-web components such as the different nutrient flux pathways. In order to be able to make long term predictions for water quality improvement in lakes and reservoirs, the combined analysis of both top-down and bottom-up forces is required.

2025, The Auk

Individuals? Populations? Interspecific interactions are key Has structure determined by….

2025, Revista Brasileira de Farmacognosia

RESUMO: "Comparação de bioensaios com os crustáceos Artemia salina e Thamnocephalus platyurus para abordagem de extratos de plantas com toxicidade". Três bioensaios de letalidade com o crustáceo de água salgada Artemia salina Leach, Artemiidae, (teste convencional em microplaca de 96 poós Artoxkit microbiotest M) e o crustáceo de água doce Thamnocephalus platyurus Packard, Thamnocephalidae (Thamnotoxkit microbiotest F), foram comparados utilizando extratos de dez espécies de plantas da Guatemala. Foi previamente observado que cinco delas possuem atividade anti-Artemia:

2025, E3S Web of Conferences

Enhancing the ecology security of Ukraine and other developing countries is predetermined by the environmental problems of cities. It prompts studies on the contamination of city's and adjacent water bodies. The control of blue-green algae distribution and the use of its biomass for production of the biofuels, energy, oils, medicine, etc. is one of the contributing factors to the well-balanced development of infrastructure of cities. The intensity of the processes of eutrophication and the species composition of the algae, which cause algal blooming, was investigated based on data of the Vorskla River in Poltava city (Ukraine). Relevant methods, statistical data of Ukrainian Environmental Service, personal observations, laboratory analysis and analytical studies were applied for the study. The comparative estimation of influence of separate biogenic and chemical substances on eutrophication processes was carried out. The approaches for prevention of processes of water bloom have...