Travis Kunnen, Ursula Scharler, David Muir. Presented at the ninth Scientific Symposium of the Western Indian Ocean Marine Science Association (WIOMSA) 2015.
GEOGRAPHIC ISOLATION OF Hypostomus cordovae (SILURIFORMES, LORICARIIDAE) IN A...YaninaFlorenciaBrioc
This study examines the population genetic structure of Hypostomus cordovae, a bottom-dwelling fish endemic to Argentina. The researchers sequenced the mitochondrial DNA control region of individuals from 14 localities across exorheic (flowing out to sea) and endorheic (internal draining) basins. They found 6 distinct haplotypes. Isolation-by-distance explained 29% of genetic variability, while isolation-by-barrier between exorheic and endorheic basins explained 53% of variability. Periodic drying of rivers likely fragmented populations, leading to genetic differentiation over time through prolonged isolation of fragmented basins.
Historical biogeography and diversification in Sisyrinchium (Iridaceae) Verônica Thode
This document summarizes a study on the historical biogeography and diversification of the plant genus Sisyrinchium. The study used a densely sampled dated phylogeny of 103 Sisyrinchium species and 13 outgroups along with 8 molecular markers and 9,000 occurrence records to address: 1) When and where Sisyrinchium colonized the New World and 2) Which geological and climatic factors influenced diversification patterns. Key results included Sisyrinchium originating in the mid-Miocene (12.7 Ma) in South America and diversifying during the Pliocene and Pleistocene, with dispersal to Central and North America earlier than the closure of the Panama Isthmus. Diversification
This study evaluated the effects of fumigation on soil nematode communities and soil food webs in pistachio orchards in California. Nematode taxa distributions were analyzed using structural, channel, and enrichment indices. Results showed that fumigation decreased the channel index, indicating a reduction in the fungal decomposition pathway. The enrichment index increased with fumigation, suggesting greater nutrient availability promoted colonizer nematode populations. While structure was initially low due to agricultural practices, there was a trend of higher structure index values under fumigation. Overall, the results demonstrate that fumigation disrupts the soil food web by reducing fungi and favoring bacterial decomposition.
Evaluating the impacts of the development of irrigation schemes in arid and s...ILRI
Poster by B. Bett, M. Said, I. Njeru, S. Kifugo, J. Gachohi, R. Sang, S. Bukachi and D. Grace presented at the Epidemics4 conference, Amsterdam, the Netherlands, 19-22 November 2013.
The document summarizes a study that analyzed the population structure of Microcystis, a genus of cyanobacteria, in a tropical freshwater reservoir undergoing a bloom, through metagenomic sequencing. The analysis identified a 5-fold increase in Microcystis assignments and 16 strains over the sampling period. Variable and conserved regions were identified by recruiting sequences to M. aeruginosa NIES-843. Single nucleotide variants within and between populations were identified, focusing on variable regions. Variants in coding regions were considered. Variants between populations seemed related to energetic metabolism, while within-population variants regulated processes like response and transcription. Housekeeping genes also showed variants potentially related to bloom growth conditions.
Land use change and the risk of selected zoonotic diseases: Observations from...ILRI
Presentation by Bernard Bett, Mohammed Said, Rosemary Sang, Salome Bukachi, Johanna Lindahl, Salome Wanyoike, Ian Njeru and Delia Grace at the 14th conference of the International Society for Veterinary Epidemiology and Economics (ISVEE), Merida, Yucatan, Mexico, 3-7 November 2015.
GEOGRAPHIC ISOLATION OF Hypostomus cordovae (SILURIFORMES, LORICARIIDAE) IN A...YaninaFlorenciaBrioc
This study examines the population genetic structure of Hypostomus cordovae, a bottom-dwelling fish endemic to Argentina. The researchers sequenced the mitochondrial DNA control region of individuals from 14 localities across exorheic (flowing out to sea) and endorheic (internal draining) basins. They found 6 distinct haplotypes. Isolation-by-distance explained 29% of genetic variability, while isolation-by-barrier between exorheic and endorheic basins explained 53% of variability. Periodic drying of rivers likely fragmented populations, leading to genetic differentiation over time through prolonged isolation of fragmented basins.
Historical biogeography and diversification in Sisyrinchium (Iridaceae) Verônica Thode
This document summarizes a study on the historical biogeography and diversification of the plant genus Sisyrinchium. The study used a densely sampled dated phylogeny of 103 Sisyrinchium species and 13 outgroups along with 8 molecular markers and 9,000 occurrence records to address: 1) When and where Sisyrinchium colonized the New World and 2) Which geological and climatic factors influenced diversification patterns. Key results included Sisyrinchium originating in the mid-Miocene (12.7 Ma) in South America and diversifying during the Pliocene and Pleistocene, with dispersal to Central and North America earlier than the closure of the Panama Isthmus. Diversification
This study evaluated the effects of fumigation on soil nematode communities and soil food webs in pistachio orchards in California. Nematode taxa distributions were analyzed using structural, channel, and enrichment indices. Results showed that fumigation decreased the channel index, indicating a reduction in the fungal decomposition pathway. The enrichment index increased with fumigation, suggesting greater nutrient availability promoted colonizer nematode populations. While structure was initially low due to agricultural practices, there was a trend of higher structure index values under fumigation. Overall, the results demonstrate that fumigation disrupts the soil food web by reducing fungi and favoring bacterial decomposition.
Evaluating the impacts of the development of irrigation schemes in arid and s...ILRI
Poster by B. Bett, M. Said, I. Njeru, S. Kifugo, J. Gachohi, R. Sang, S. Bukachi and D. Grace presented at the Epidemics4 conference, Amsterdam, the Netherlands, 19-22 November 2013.
The document summarizes a study that analyzed the population structure of Microcystis, a genus of cyanobacteria, in a tropical freshwater reservoir undergoing a bloom, through metagenomic sequencing. The analysis identified a 5-fold increase in Microcystis assignments and 16 strains over the sampling period. Variable and conserved regions were identified by recruiting sequences to M. aeruginosa NIES-843. Single nucleotide variants within and between populations were identified, focusing on variable regions. Variants in coding regions were considered. Variants between populations seemed related to energetic metabolism, while within-population variants regulated processes like response and transcription. Housekeeping genes also showed variants potentially related to bloom growth conditions.
Land use change and the risk of selected zoonotic diseases: Observations from...ILRI
Presentation by Bernard Bett, Mohammed Said, Rosemary Sang, Salome Bukachi, Johanna Lindahl, Salome Wanyoike, Ian Njeru and Delia Grace at the 14th conference of the International Society for Veterinary Epidemiology and Economics (ISVEE), Merida, Yucatan, Mexico, 3-7 November 2015.
Supporting evidence for a cryptic species within the Neotropical freshwater f...Izabela Mendes
Presentation by Izabela Santos Mendes for the I Virtual Meeting of Systematics, Biogeography and Evolution (SBE).
Authors: Izabela Santos Mendes, Bruno Francelino de Melo, Daniel Fonseca Teixeira, Júnio Damasceno Souza, Daniel Cardoso Carvalho.
An integrative multi-approach workflow resolves species limits in the souther...KevinISnchez1
This study used an integrative approach combining genomic, morphological, and phylogenetic analyses to assess species limits in five members of the Liolaemus kingii lizard group in southern Argentina. The analyses confirmed the validity of four species - L. baguali, L. tari, L. escarchadosi, and L. sarmientoi - and provided further evidence for the independent status of L. sp. A. Some weak nuclear introgression was detected between certain species pairs. The study demonstrated the value of combining multiple types of data to test species hypotheses and overcome limitations of single-method approaches.
1) Researchers trapped and photographed paper wasps across an elevational gradient in the Colombian Andes to examine how their body color varied with elevation.
2) They found that wasps from higher elevations had significantly darker thoraxes, supporting the prediction that ectotherms are darker at higher elevations to aid heat absorption and provide photoprotection from UV radiation.
3) In contrast, the coloration of other body parts like the head and abdomen did not consistently vary with elevation, except the clypeus which became more matte at higher elevations, suggesting darker thoraxes specifically aid thermoregulation in wasps living in colder, high-elevation environments.
Do pitcher plants control the assembly of pitcher microbiomes?Leonora Bittleston
The document summarizes a study investigating the factors influencing the assembly of microbial communities within the pitchers of three Nepenthes plant species in Singapore. The study finds that bacterial and eukaryotic community composition in the pitchers is most influenced by the host plant species and pH level. While collection site and pitcher volume also have significant effects, bacterial and eukaryotic diversity are strongly correlated, suggesting similar responses to environmental conditions rather than interactions between organisms shaping the communities. Deterministic factors like biochemical characteristics have a stronger influence on community assembly than stochastic factors like chance colonization.
River Deep, Mountain High: do geographic barriers restrain gene flow in Petun...Luana Sousa
This study examines whether the Pelotas River acts as a geographic barrier to gene flow between populations of Petunia altiplana plant on opposite banks. Analysis of chloroplast DNA shows distinct haplotypes on the north and south banks, indicating the river limits gene flow. However, analysis of microsatellite markers reveals less population structure and some shared alleles between banks, suggesting possible gene flow. The authors plan to analyze additional markers to clarify the river's role in structuring P. altiplana populations.
Diatom biogeography: distribution of the Luticola species found in Iguazú Nat...JulinSimonato
The document summarizes a study on the diatom genus Luticola found in Iguazú National Park in Argentina. 18 Luticola species were identified from samples collected at 8 sites within the park. Most species had Neotropical or tropical distributions, while 2 were cosmopolitan and 2 had disjunct distributions. The results indicate high diatom diversity and endemism within the park and add to understanding biogeography patterns of the genus in South America.
This study aimed to delimit species boundaries within the Brazilian cactus genus Uebelmannia using ddRAD-seq data and coalescent-based methods. Analysis of 5,386 loci from individuals representing the currently recognized 6 taxa recovered 12 operational taxonomic units using species tree inference but failed to fully resolve species boundaries. Genealogical divergence index values supported two divergent lineages that correspond to geography and morphology, albeit with some taxa grouped together. Integrating additional data sources like morphology may be needed to fully resolve species limits in this highly structured microendemic genus.
This document provides information about monitoring benthic macroinvertebrates in Kushog Lake to assess lake health. It describes what benthic macroinvertebrates are and why they are useful for biological monitoring of water quality. Several indicators of water quality are identified based on the types of invertebrates present, such as the number of taxa collected (richness), the percentage of mayflies, dragonflies and caddisflies (%EPT), and the Hilsenhoff Index value. Recommendations are provided for monitoring benthic macroinvertebrates in Kushog Lake to evaluate lake health over time.
So close no matter how far: sympatric slow worm lizards look alike but share ...EvanthiaThanou1
This study analyzed genetic and environmental data from two slow worm lizard species, Anguis greaca and A. cephallonica, that are morphologically similar but have distinct evolutionary histories. Genomic analysis showed no genetic admixture or gene flow between the species and population structure correlated with geographic distance. Species distribution models found little niche overlap, with each species associated with different climatic variables. The results reject hypotheses of recent hybridization or convergent evolution, and instead suggest morphological similarity reflects ancient shared ancestry.
Fall poster-Seasonal Variation of the Geochemistry and the EffectsMichelle C Bennett
1) Microbial communities in the Fraser River vary seasonally and correlate with environmental factors like temperature, turbidity, ammonia, and silica. Certain bacteria like Sphingobacteria and Flavobacteria indicate seasonal changes and are more abundant in summer months.
2) The document analyzes samples from the Fraser River and its tributaries to understand the link between microbial diversity, river geochemistry, and transported particles. Economic activities in the Fraser River Basin include forestry, fishing, agriculture, and more.
3) Analysis found the most abundant bacteria phyla responded to changes in temperature, ammonia, turbidity, and silica. Sphingobacteria were more abundant in summer months compared to Flavobacteria
Urban metabolism is the study of the physical flows required to serve the urban economy. The document discusses scales of urban metabolism including the urban metabolism of the Back Bay neighborhood in Boston, the urban metabolism of the MIT campus, and the resource intensity of one undergraduate year of study.
Jack Gilbert: Welcome to the 1st International EMP Meeting: the first 10,000 ...GigaScience, BGI Hong Kong
This document summarizes the First International EMP meeting and the Earth Microbiome Project's pilot study. The EMP aims to catalog microbial diversity globally by sequencing 10,000 environmental samples. So far over 60,000 samples have been pledged from over 50 researchers worldwide. Analysis of initial samples shows robust seasonal patterns in species richness. The EMP also aims to correlate taxonomic data with environmental parameters and functional gene profiles to better understand microbial communities and predict assemblages.
This project examines the role of microbial activities in controlling phosphorus mobility in landscapes prone to saturation-drying cycles, from continuously saturated streams to variably saturated soils. Laboratory and field experiments were conducted to better understand how hydrology and microbes interact to affect phosphorus retention and release. Results showed that stream biofilms accumulated phosphorus, mostly as polyphosphate, in response to external phosphorus loading levels independently of biofilm biomass. Diurnal changes in oxygen levels within biofilms, mimicking natural conditions, promoted phosphorus release under anaerobic conditions and removal under aerobic conditions, likely due to the activity of polyphosphate-accumulating organisms (PAOs). The identification of putative PAO populations in stream biofilms provided insights
The document provides a summary of the Microbial Genomics 2008 conference held in Lake Arrowhead, California. It discusses several topics that were covered at the conference, including biofuels production using metabolic engineering of E. coli, the Genomic Encyclopedia of Bacteria and Archaea project to sequence bacterial genomes, the Human Microbiome Project to study microbes that live in and on the human body, using metagenomics to study viral ecology in marine environments, identifying essential genes in yeast, studying persister cells in bacterial populations, and discovering new antibacterial targets. Feedback was requested on the training session.
CNR: Sustainable Soil Management to reduce agricultural inputs: What is the r...ExternalEvents
This presentation was presented during Day 3 of the Global Soil Partnership Plenary Assembly – 5th Session that took place at FAO Hq in Rome, Italy, from 20 to 22 June 2017. The presentation was made by Raffaella M. Balestrini
This study investigated nitrogen transformations in aquaponic systems under different conditions. The main findings were:
1) Nitrate continuously accumulated in the recirculating water, termed the "Balloon Effect", because nitrate input from fish waste exceeded plant uptake.
2) Denitrification, the conversion of nitrates/nitrites to nitrogen gas, was found to be the major source of nitrogen loss. Higher dissolved oxygen and lower feeding rates decreased denitrification.
3) Isotopic analysis showed denitrification rates were higher under low dissolved oxygen conditions, as evidenced by higher nitrate δ15N values. This supported denitrification as the primary nitrogen loss pathway.
This study examined genetic differentiation in laboratory populations of Drosophila subobscura derived from six wild populations collected from different locations and years. The researchers found striking genetic differentiation between the laboratory populations within the first two generations of being established, despite all founders being similar. This early divergence was likely due to strong genetic drift and changes in demography resulting from a significant drop in effective population size during the colonization process. The results demonstrate that rapid and significant evolutionary changes can occur during the initial generations of a founding event in a new environment due to powerful genetic sampling effects.
This document reports on a study that examined the relationship between bacterial diversity and primary productivity in aquatic mesocosms designed to mimic small ponds. The key findings were:
1) Bacterial richness, as estimated by sequencing 16S rDNA from samples, varied along the gradient of primary productivity created by altering nutrient inputs in the mesocosms.
2) Different bacterial taxonomic groups (Cytophaga-Flavobacteria-Bacteroides, Alpha-proteobacteria, Beta-proteobacteria) exhibited different relationships between richness and productivity - hump shaped, U-shaped, and no relationship, respectively.
3) This is one of the first studies to demonstrate that bacterial diversity
The document describes a study examining changes in hydrolysable amino acids during soil development. Key points:
- Hydrolysable amino acid composition changed over time and differed between seasons, indicating changes in soil protein patterns during pedogenesis.
- Changes in amino acid composition aligned with hypotheses about soil organic matter formation being influenced by shifting sources (plants and microbes) and sinks (mineral associations).
- Early-successional bacterial communities like Actinobacteria, high in alanine and glycine, declined over time, changing amino acid pools. Acidobacteria increased and are rich in histidine peptides.
- Shifting bacterial communities and associations with soil minerals likely drove changes in hydrolysable amino acids and
This document provides an overview of viruses in the marine environment. It discusses that viruses are the most abundant component of the plankton community, with an estimated 1030 viruses in the ocean. Viruses play important roles in marine health by controlling bacterial and algal populations, influencing microbial food webs and nutrient cycling. They also play a role in microbial diversity and the structure of aquatic microbial communities through limiting specific bacteria and phytoplankton populations.
Este documento contiene una autoevaluación de un proyecto que incluye indicadores sobre el producto final del proyecto, la colaboración en el equipo, la tolerancia y respeto a los demás, el uso de habilidades para el trabajo en equipo, el enriquecimiento de conocimientos sobre psicología, la originalidad y creatividad, y la entrega a tiempo. También incluye una coevaluación del proyecto preguntando qué y cómo se aprendió y cómo será útil eso en el futuro.
El documento habla sobre el fútbol. Menciona a algunos de los mejores jugadores de todos los tiempos como Pelé, Maradona y Messi. También destaca a exponentes colombianos como Pibe, Andrés Escobar, René Higuita y James Rodríguez. Lista a los mejores equipos del mundo como Real Madrid, Barcelona, Bayern Múnich y Manchester City. Finalmente, nombra los principales torneos de fútbol como la Copa Mundial, Champions League y Copa Libertadores.
Supporting evidence for a cryptic species within the Neotropical freshwater f...Izabela Mendes
Presentation by Izabela Santos Mendes for the I Virtual Meeting of Systematics, Biogeography and Evolution (SBE).
Authors: Izabela Santos Mendes, Bruno Francelino de Melo, Daniel Fonseca Teixeira, Júnio Damasceno Souza, Daniel Cardoso Carvalho.
An integrative multi-approach workflow resolves species limits in the souther...KevinISnchez1
This study used an integrative approach combining genomic, morphological, and phylogenetic analyses to assess species limits in five members of the Liolaemus kingii lizard group in southern Argentina. The analyses confirmed the validity of four species - L. baguali, L. tari, L. escarchadosi, and L. sarmientoi - and provided further evidence for the independent status of L. sp. A. Some weak nuclear introgression was detected between certain species pairs. The study demonstrated the value of combining multiple types of data to test species hypotheses and overcome limitations of single-method approaches.
1) Researchers trapped and photographed paper wasps across an elevational gradient in the Colombian Andes to examine how their body color varied with elevation.
2) They found that wasps from higher elevations had significantly darker thoraxes, supporting the prediction that ectotherms are darker at higher elevations to aid heat absorption and provide photoprotection from UV radiation.
3) In contrast, the coloration of other body parts like the head and abdomen did not consistently vary with elevation, except the clypeus which became more matte at higher elevations, suggesting darker thoraxes specifically aid thermoregulation in wasps living in colder, high-elevation environments.
Do pitcher plants control the assembly of pitcher microbiomes?Leonora Bittleston
The document summarizes a study investigating the factors influencing the assembly of microbial communities within the pitchers of three Nepenthes plant species in Singapore. The study finds that bacterial and eukaryotic community composition in the pitchers is most influenced by the host plant species and pH level. While collection site and pitcher volume also have significant effects, bacterial and eukaryotic diversity are strongly correlated, suggesting similar responses to environmental conditions rather than interactions between organisms shaping the communities. Deterministic factors like biochemical characteristics have a stronger influence on community assembly than stochastic factors like chance colonization.
River Deep, Mountain High: do geographic barriers restrain gene flow in Petun...Luana Sousa
This study examines whether the Pelotas River acts as a geographic barrier to gene flow between populations of Petunia altiplana plant on opposite banks. Analysis of chloroplast DNA shows distinct haplotypes on the north and south banks, indicating the river limits gene flow. However, analysis of microsatellite markers reveals less population structure and some shared alleles between banks, suggesting possible gene flow. The authors plan to analyze additional markers to clarify the river's role in structuring P. altiplana populations.
Diatom biogeography: distribution of the Luticola species found in Iguazú Nat...JulinSimonato
The document summarizes a study on the diatom genus Luticola found in Iguazú National Park in Argentina. 18 Luticola species were identified from samples collected at 8 sites within the park. Most species had Neotropical or tropical distributions, while 2 were cosmopolitan and 2 had disjunct distributions. The results indicate high diatom diversity and endemism within the park and add to understanding biogeography patterns of the genus in South America.
This study aimed to delimit species boundaries within the Brazilian cactus genus Uebelmannia using ddRAD-seq data and coalescent-based methods. Analysis of 5,386 loci from individuals representing the currently recognized 6 taxa recovered 12 operational taxonomic units using species tree inference but failed to fully resolve species boundaries. Genealogical divergence index values supported two divergent lineages that correspond to geography and morphology, albeit with some taxa grouped together. Integrating additional data sources like morphology may be needed to fully resolve species limits in this highly structured microendemic genus.
This document provides information about monitoring benthic macroinvertebrates in Kushog Lake to assess lake health. It describes what benthic macroinvertebrates are and why they are useful for biological monitoring of water quality. Several indicators of water quality are identified based on the types of invertebrates present, such as the number of taxa collected (richness), the percentage of mayflies, dragonflies and caddisflies (%EPT), and the Hilsenhoff Index value. Recommendations are provided for monitoring benthic macroinvertebrates in Kushog Lake to evaluate lake health over time.
So close no matter how far: sympatric slow worm lizards look alike but share ...EvanthiaThanou1
This study analyzed genetic and environmental data from two slow worm lizard species, Anguis greaca and A. cephallonica, that are morphologically similar but have distinct evolutionary histories. Genomic analysis showed no genetic admixture or gene flow between the species and population structure correlated with geographic distance. Species distribution models found little niche overlap, with each species associated with different climatic variables. The results reject hypotheses of recent hybridization or convergent evolution, and instead suggest morphological similarity reflects ancient shared ancestry.
Fall poster-Seasonal Variation of the Geochemistry and the EffectsMichelle C Bennett
1) Microbial communities in the Fraser River vary seasonally and correlate with environmental factors like temperature, turbidity, ammonia, and silica. Certain bacteria like Sphingobacteria and Flavobacteria indicate seasonal changes and are more abundant in summer months.
2) The document analyzes samples from the Fraser River and its tributaries to understand the link between microbial diversity, river geochemistry, and transported particles. Economic activities in the Fraser River Basin include forestry, fishing, agriculture, and more.
3) Analysis found the most abundant bacteria phyla responded to changes in temperature, ammonia, turbidity, and silica. Sphingobacteria were more abundant in summer months compared to Flavobacteria
Urban metabolism is the study of the physical flows required to serve the urban economy. The document discusses scales of urban metabolism including the urban metabolism of the Back Bay neighborhood in Boston, the urban metabolism of the MIT campus, and the resource intensity of one undergraduate year of study.
Jack Gilbert: Welcome to the 1st International EMP Meeting: the first 10,000 ...GigaScience, BGI Hong Kong
This document summarizes the First International EMP meeting and the Earth Microbiome Project's pilot study. The EMP aims to catalog microbial diversity globally by sequencing 10,000 environmental samples. So far over 60,000 samples have been pledged from over 50 researchers worldwide. Analysis of initial samples shows robust seasonal patterns in species richness. The EMP also aims to correlate taxonomic data with environmental parameters and functional gene profiles to better understand microbial communities and predict assemblages.
This project examines the role of microbial activities in controlling phosphorus mobility in landscapes prone to saturation-drying cycles, from continuously saturated streams to variably saturated soils. Laboratory and field experiments were conducted to better understand how hydrology and microbes interact to affect phosphorus retention and release. Results showed that stream biofilms accumulated phosphorus, mostly as polyphosphate, in response to external phosphorus loading levels independently of biofilm biomass. Diurnal changes in oxygen levels within biofilms, mimicking natural conditions, promoted phosphorus release under anaerobic conditions and removal under aerobic conditions, likely due to the activity of polyphosphate-accumulating organisms (PAOs). The identification of putative PAO populations in stream biofilms provided insights
The document provides a summary of the Microbial Genomics 2008 conference held in Lake Arrowhead, California. It discusses several topics that were covered at the conference, including biofuels production using metabolic engineering of E. coli, the Genomic Encyclopedia of Bacteria and Archaea project to sequence bacterial genomes, the Human Microbiome Project to study microbes that live in and on the human body, using metagenomics to study viral ecology in marine environments, identifying essential genes in yeast, studying persister cells in bacterial populations, and discovering new antibacterial targets. Feedback was requested on the training session.
CNR: Sustainable Soil Management to reduce agricultural inputs: What is the r...ExternalEvents
This presentation was presented during Day 3 of the Global Soil Partnership Plenary Assembly – 5th Session that took place at FAO Hq in Rome, Italy, from 20 to 22 June 2017. The presentation was made by Raffaella M. Balestrini
This study investigated nitrogen transformations in aquaponic systems under different conditions. The main findings were:
1) Nitrate continuously accumulated in the recirculating water, termed the "Balloon Effect", because nitrate input from fish waste exceeded plant uptake.
2) Denitrification, the conversion of nitrates/nitrites to nitrogen gas, was found to be the major source of nitrogen loss. Higher dissolved oxygen and lower feeding rates decreased denitrification.
3) Isotopic analysis showed denitrification rates were higher under low dissolved oxygen conditions, as evidenced by higher nitrate δ15N values. This supported denitrification as the primary nitrogen loss pathway.
This study examined genetic differentiation in laboratory populations of Drosophila subobscura derived from six wild populations collected from different locations and years. The researchers found striking genetic differentiation between the laboratory populations within the first two generations of being established, despite all founders being similar. This early divergence was likely due to strong genetic drift and changes in demography resulting from a significant drop in effective population size during the colonization process. The results demonstrate that rapid and significant evolutionary changes can occur during the initial generations of a founding event in a new environment due to powerful genetic sampling effects.
This document reports on a study that examined the relationship between bacterial diversity and primary productivity in aquatic mesocosms designed to mimic small ponds. The key findings were:
1) Bacterial richness, as estimated by sequencing 16S rDNA from samples, varied along the gradient of primary productivity created by altering nutrient inputs in the mesocosms.
2) Different bacterial taxonomic groups (Cytophaga-Flavobacteria-Bacteroides, Alpha-proteobacteria, Beta-proteobacteria) exhibited different relationships between richness and productivity - hump shaped, U-shaped, and no relationship, respectively.
3) This is one of the first studies to demonstrate that bacterial diversity
The document describes a study examining changes in hydrolysable amino acids during soil development. Key points:
- Hydrolysable amino acid composition changed over time and differed between seasons, indicating changes in soil protein patterns during pedogenesis.
- Changes in amino acid composition aligned with hypotheses about soil organic matter formation being influenced by shifting sources (plants and microbes) and sinks (mineral associations).
- Early-successional bacterial communities like Actinobacteria, high in alanine and glycine, declined over time, changing amino acid pools. Acidobacteria increased and are rich in histidine peptides.
- Shifting bacterial communities and associations with soil minerals likely drove changes in hydrolysable amino acids and
This document provides an overview of viruses in the marine environment. It discusses that viruses are the most abundant component of the plankton community, with an estimated 1030 viruses in the ocean. Viruses play important roles in marine health by controlling bacterial and algal populations, influencing microbial food webs and nutrient cycling. They also play a role in microbial diversity and the structure of aquatic microbial communities through limiting specific bacteria and phytoplankton populations.
Este documento contiene una autoevaluación de un proyecto que incluye indicadores sobre el producto final del proyecto, la colaboración en el equipo, la tolerancia y respeto a los demás, el uso de habilidades para el trabajo en equipo, el enriquecimiento de conocimientos sobre psicología, la originalidad y creatividad, y la entrega a tiempo. También incluye una coevaluación del proyecto preguntando qué y cómo se aprendió y cómo será útil eso en el futuro.
El documento habla sobre el fútbol. Menciona a algunos de los mejores jugadores de todos los tiempos como Pelé, Maradona y Messi. También destaca a exponentes colombianos como Pibe, Andrés Escobar, René Higuita y James Rodríguez. Lista a los mejores equipos del mundo como Real Madrid, Barcelona, Bayern Múnich y Manchester City. Finalmente, nombra los principales torneos de fútbol como la Copa Mundial, Champions League y Copa Libertadores.
Cold Molecular Gas in Merger Remnants. I. Formation of Molecular Gas DiscsGOASA
- 80% (24/30) of the merger remnants with robust CO detections showed kinematical signatures of rotating molecular gas disks (including nuclear rings) based on their velocity fields. The sizes of these disks varied significantly from 1.1 kpc to 9.3 kpc.
- In 54% of the sources, the size of the molecular gas disks was more compact than the K-band effective radius, possibly formed from past gas inflows triggered by dynamical instabilities during mergers.
- The remaining 46% had more extended gas disks relative to the stellar component, possibly forming late-type galaxies with central stellar bulges.
- The study suggests that nuclear and extended molecular gas disks are common in
1) Se describen las sucesiones aritméticas, cuyo término general se expresa como an + b, donde a y b son constantes y n es el número del término.
2) Se muestran dos ejemplos para ilustrar cómo encontrar el término general de una sucesión dada y calcular términos individuales y sumas parciales.
3) El primer ejemplo muestra una sucesión creciente con diferencia 3 y el segundo una sucesión decreciente con diferencia -6.
La Parroquia San José de Pemuco necesita ser reconstruida después de un terremoto en 2010 y agregar nuevos servicios para satisfacer las necesidades de la comunidad rural. El proyecto propone construir un Centro Parroquial con espacios como sala comunitaria, talleres y sala de estar asociada al velatorio.
This document discusses emotional abuse and provides guidance for identifying it. Emotional abuse can be difficult to detect as there are no physical scars. However, some signs are a "haggard" look, confusion, anger without a clear cause, reluctance to communicate with their partner, atypical depression or anxiety without a clear reason, and a lost sense of self. The abuser often blames the abused for problems and does not see their own abusive behaviors as a fault. Therapy is focused on the abused person's problems. Suggestions are provided for helping emotionally abused clients leave abusive situations if they choose and for developing coping skills to deal with the abuse.
Aktuelle Cloud Services: Weltweit gibt es immer mehr Anbieter für Datenspeicher in der Cloud. Wir haben die bekanntesten analysiert und die Ergebnisse zusammengestellt.
O documento descreve as propriedades e usos do nim (Azadirachta indica) no controle de pragas de forma orgânica. O nim contém substâncias como azadirachtina que tem propriedades inseticidas e pode controlar mais de 413 espécies de pragas em cultivos e criações. Ele também tem propriedades medicinais, cosméticas e pode ser usado na agricultura, pecuária e no controle de doenças humanas. O documento fornece instruções sobre como preparar e aplicar o extrato de nim para o controle de diferentes pragas em
First Financial Sevices Overview Sports NEWMatt Thomas
This document provides an overview of financial and legal services offered across various areas including residential and commercial mortgages, investment planning, wealth management, legal services, protection advice, retirement planning, and specialized services for sports professionals. The core values emphasized are honesty and integrity, high quality service, and expert advice.
Samantha Riley is presenting on social media for Slideshare test. The presentation will cover trends in social media usage and how businesses can leverage different social platforms like Facebook, Twitter, and LinkedIn to engage customers and drive sales. An analysis of case studies will show how other companies have successfully used social media for marketing purposes.
This seminar presentation discusses outlier detection in high dimensional data by integrating feature selection algorithms. The presenter is M.Rao Batchanaboyina, a student with the identification Y15CSER028. The seminar is being presented under the guidance of Dr. D.Naga Raju, a Professor.
La leyenda cuenta que antes de nacer, un niño le preguntó a Dios sus preocupaciones sobre vivir en la Tierra pequeño e indefenso. Dios le aseguró que había escogido un ángel para cuidarlo y protegerlo, que le cantaría, sonreiría y enseñaría a orar, y que aunque no vería a Dios, el ángel siempre lo guiaría de regreso. Cuando el niño pidió el nombre de su ángel, Dios respondió que no importaba, y que él le diría "Mamá".
O documento descreve os benefícios do uso do produto Fish Mais na cana-de-açúcar, incluindo maior desenvolvimento radicular, absorção de nutrientes, germinação e resistência a pragas. Testes em uma fazenda demonstraram que o uso de Fish Mais proporcionou plantio mais uniforme e vigoroso com redução no uso de agrotóxicos.
Three distinct groups of picoplankton were identified in the Patagonian Shelf region: Prochlorococcus, Synechococcus, and picoeukaryotes. Prochlorococcus populations were detected at four stations within the Brazil Current but did not extend further south than 40°S. Cyanobacterial abundance, primarily Synechococcus, was greatest in warmer, more oligotrophic conditions corresponding to regions outside the shelf break. Picoeukaryotes dominated at most other stations. Heterotrophic bacteria abundances were two orders of magnitude higher than autotrophs, indicating rapid nutrient recycling. Cyanobacterial abundance correlated positively with temperature and negatively with nutrients, influenced by hydrographic features and seasonal blooms in the
This document is a dissertation submitted in partial fulfillment of a Bachelor's degree in environmental sciences. It presents the results of a study monitoring the phytoplankton communities in a eutrophic Irish lake over a 6-month period from January to July 2012. Phytoplankton assemblages were found to follow clear seasonal successional patterns related to changing water quality and nutrient conditions. Their composition supported the lake's status as healthy but bordering on mesotrophic/eutrophic. The study evaluated phytoplankton as biological indicators for monitoring water quality and ecological status under the EU Water Framework Directive.
IRJET - Studies on Algal Flora in Fox Sagar Lake, Jeedimetla, HyderabadIRJET Journal
1. The document studied the algal flora in Fox Sagar Lake in Hyderabad, India over a two year period.
2. Four groups of algae were observed - Cyanophyceae, Chlorophyceae, Bacillariophyceae, and Euglenophyceae. Cyanophyceae dominated all groups, making up around 80% of algae.
3. The abundance and distribution of different algal groups varied seasonally and was influenced by environmental factors like temperature, organic matter, nutrients. Cyanophyceae blooms indicated eutrophic conditions in the lake.
Bacterial indicators and antibiotic resistance of Escherichia coli in groundw...Agriculture Journal IJOEAR
— The aim of this research was to investigate the groundwater quality in El Barreal basin (Córdoba, Argentina), through bacteriological analysis and antibiotic resistance of fecal bacteria indicators and their relationship with geochemical and land uses characteristics. Groundwater samples were collected in 36 wells and the following parameters were determined: major chemical components, heterotrophic plate counts, total and fecal coliforms, Escherichia coli and Pseudomonas aeruginosa. Antibiotic resistance of E. coli was analyzed using standard methods. The chemical and bacteriological analysis showed that more than 80 % of samples were unfit for human consumption. Bacteriological contamination was significant in 36 % of samples. The multivariate analysis between bacterial and geochemical variables explained local contamination conditions, evidenced by the arrival of bacteria and some typical indicators (NO 3-, Cl-y HCO 3-) to groundwater. No significant correlation between NO 3-and bacterial counts was observed, which let us to interpret that part of NO 3-contents can be supplied by inorganic fertilizers. Total and fecal coliforms were linked to a local increase of Cl-and HCO 3-and a decrease of pH and dissolved oxygen, indicating the arrival and degradation of organic matter into groundwater. The resistance pattern of total E. coli isolates (n=12) showed that the highest percentages were observed for antibiotics of animal use (ampicillin, tetracycline and cephalothin). The analysis of results revealed the impact of land uses demonstrating that livestock activities are the main punctual contaminant sources in this sedimentary aquifer.
High scientific demand, sustainable management of sea
resources, assessment and monitoring of pollution sources and of
their environmental impact, urgency to understand how does the
biologic processes link to the Carbon cycle and how do they
impact climate: oceanic biologic parameters (primary production,
biomass, and pelagic populations) are in the depths of vital stakes
for our society sustainable development.
Today, Mercator-Ocean is strongly involved in producing
operational bulletins of the physical “blue” ocean. To use new
requirements, it is going to integrate the forecasting of the living
world seas’ component and become more “green”. A first quasireal
time demonstration phase will be launched in the beginning of
2006. LOBSTER biologic model will be integrated in the Mercator
operational chain. This new stage was made possible thanks to
the Bionuts research/operational collaboration. Five structures
contribute to this project: LEGOS (Toulouse), LEGI (Grenoble),
IPSL/OCEAN and IPSL/LSCE (Paris) and the GIP Mercator-
Ocean. In the News, Patrick Monfray & al. present us this project,
its stakes, as well as some recent results.
The three other Newsletter’s articles present an overview of the
Mercator associated research works on the “biology” thematic.
François Royer & al. are interested on the pelagic species’ spatial
dynamic, unavoidable stage for a better management of the sea
resources.
A toxic bloom of the cyanobacteria, Nodularia
spumigena has been reported in the Baltic Sea. On
July 24, 2003, SeaWiFS captured this view of the
blooming Baltic. (credits NASA)
In the scope of the Bionuts project, Leo Berline & al. have studied the assimilation impact (temperature, salinity, sea level)
on the biologic parameters of coupled biology/physical model. In fact, the confrontation of physical models to biology
constraints has revealed some negative effects of the assimilation scheme on the vertical processes performance. So,
improve them is a crucial stake for the biology/physical coupling.
At last, coupling between biologic and physical models is a great opportunity for Scientists to investigate how does the
dynamic impact the biology. Isabelle Dadou & al. have looked at the Rossby waves influence on the primary production.
Have a very good read!
This study examined the impact of human activity on water quality near Avalon Bay, Catalina Island, CA. Water samples were collected from 4 stations located 1-2 miles from the bay at varying depths. Tests found higher levels of ammonium, nitrate, fecal bacteria and chlorophyll closer to the bay, indicating pollution from sources like sewage. Farther from the bay, levels of these contaminants decreased while biomass and total microorganisms increased, showing less negative human impact. The results support the hypothesis that waters nearer to the human population center exhibit stronger signs of contamination than more distant waters.
Inorganic and methylmercury do they transfer along a tropical coastal food ...racheltrans
This study evaluated methylmercury (MeHg) and inorganic mercury (Hginorg) concentrations in water, plankton, and fish from Guanabara Bay, a eutrophic coastal area in Brazil. The aims were to compare the trophic transfer and biomagnification of MeHg and Hginorg between different trophic levels in the food web, from plankton to predatory fish. Water, microplankton, mesoplankton, and muscle tissue from 7 fish species with different feeding habits were sampled. Results showed that MeHg concentrations and proportions increased with trophic level, while Hginorg decreased, indicating MeHg was the species that biomagnified. MeHg also reflected the vertical
Utilization of Multiple Habitat Sampling Protocol for Macroinvertebrates as Indicators of Water
Quality in Stream Ecosystem in Lawis,
Buruun, Iligan City
This study found high concentrations of viruses in water samples from the Chesapeake Bay. Virus counts ranged from 2.6 x 106 to 1.4 x 108 viruses per ml and averaged 2.5 x 107 viruses per ml. Virus counts were usually at least three times higher than bacterial counts from the same samples. Virus concentrations were highest in August and October and lowest in April and September. The high virus counts suggest that viruses may be an important factor influencing bacterial populations in the Chesapeake Bay through infection.
Analyses of Community Attributes of Meiofauna Under A Pollution Regime in the...Agriculture Journal IJOEAR
— Meiofauna community attributes of the lower Bonny estuary was investigated under a pollution regime. This is germane because of the strategic importance of meiofauna in the food chain and the sustenance of any aquatic ecosystem. Five stations representing diverse land based activities such as refuse dump site, fuel depot, fishing-landing areas, residential housing and a station located upstream (control) were chosen for investigation. The meiofauna samples were collected from sediments in three replicate spots per station per sampling months at low tide. Sediment samples were stirred through (63-212nm) meshes to separate meiofauna and organic debris. Meiofauna samples were processed by first washing Meiofauna through a sieve of fine mesh size made of silk material, in order to wash off formation and excess silt or mud. Meiofauna samples were sorted out and identified using standard keys. Result from field studies indicate that meiofauna population abundance and diversity varied slightly between stations and seasons. There was however, no established trend. Meiofauna were generally more abundant in the rainy season than in the dry season. In general, pollution indicator meiofaunal taxa were more in all stations except the control station; the increasing impact of pollutants in the river led to a rise in the relative abundance of r-strategist genera like Chromadora. We conclude that the application of meiofaunal indices can be a useful tool for assessing the environmental quality of estuarine ecosystems.
The document discusses using bioremediation through biofilm and macrophyte management (BioMac) to improve water quality in a polluted tropical urban river in Brazil. Monitoring was conducted before and after installing BioMac structures. Results showed that after installation, there was a large decrease in nutrients along the river, increased transparency, biological diversity, and dissolved oxygen. This effect was strongest in the most polluted areas. It was concluded that the low-cost BioMac pilot system was effective at reducing phosphates, increasing nitrification, and improving water quality, making it a potential tool for depolluting rivers receiving sewage.
This study analyzed nutrient and bacterial concentrations in Bowne Park Pond over time. Algal blooms were previously observed, indicating potential eutrophication. Water samples were tested for nutrients and bacteria using various methods. Results showed high nutrient levels, likely due to surface runoff during heavy rainfall. Total coliform levels increased from 18 to 24 hours of incubation. Enterococcus levels remained relatively constant, suggesting it may be a more stable indicator of contamination than E. coli or total coliform. Future studies are needed to determine if the pond is prone to eutrophication, and if remedial actions are required to protect the marine habitat and public.
Monitoring the Occurrence of Microbes in a Wellhead Protection Area in an Agr...guestdd2f4b
The document summarizes research on characterizing microbial risks to municipal groundwater in an agricultural setting. The research aimed to: 1) assess temporal and spatial trends of microbes within a wellhead protection area, 2) assess factors controlling vulnerability of wells to microbial contamination compared to dissolved contaminants, and 3) examine how policy treats microbial risks to better characterize the risks. The research found consistent occurrences of microbes throughout the aquifer system, highest concentrations correlated with meltwater events, and microbes occurred infrequently in municipal wells even under vulnerable conditions.
Trophic state indices and Phytoplankton quotients for the Kisumu Bay, Lake Vi...Douglas Anyona
This study aimed to estimate phytoplankton quotients and trophic state indices for Kisumu Bay in Lake Victoria to determine the bay's eutrophic level. Water and phytoplankton samples were collected from 5 stations in the bay from 2009-2010. Cyanophyceae was the most dominant phytoplankton group at 57%. The mean phytoplankton quotient was estimated to be 4.1, indicating a high eutrophic state. Nutrient levels were also high, with total phosphorus at 289.6 μg/L and total nitrogen at 1518.5 μg/L. The elevated eutrophic state was attributed to high nutrient loads from anthropogenic activities, industrial and
Researchers sampled water at a dock in Mukilteo, Washington monthly from June to September 2011 to analyze plankton populations over time. Samples were taken using a Niskin bottle to determine the water layer where plankton were found most abundant. The samples were strained through a net and portions were preserved and counted under a microscope. The study found the highest plankton populations in July, with over 2,000 individuals counted, compared to 300-400 in other months. Phytoplankton, which made up 80% of species, peaked in July along with nutrient levels, suggesting plankton growth was correlated with increased nutrients.
Artifi cial wetlands are useful for wastewater treatment; however, relatively little is known of the effects of sewage on artifi cial wetland microbial community structure. Therefore, we assessed the effect of municipal sewage on microbial community diversity in surface water throughout an artifi cial wetland (Xiantao artifi cial wetland) treating municipal sewage. We analyzed the relationship between physicochemical parameters of surface water (i.e., Chemical Oxygen Demand (COD), Total Nitrogen (TN), Total Phosphorus (TP), and
NH4+-N) with microbial community structure (Illumina MiSeq sequencing followed by abundance indices). The results showed that the total microbial community in surface water was signifi cantly correlated with COD, TN, TP, and NH4
+-N (r = 0.764, 0.897, 0.883, 0.839, P < 0.05). In addition, the most abundant taxa were significantly correlated with COD (r = 0.803, P < 0.05). The relative abundance of rare operational taxonomic units in the more purifi ed water farther downstream was higher than in the polluted area, suggesting that rare groups were more sensitive to physicochemical parameters than abundant groups, and that the abundance of some bacteria could indirectly indicate the degree of aquatic pollution. Our results indicate that the responses of microorganisms in artificial wetlands to environmental conditions should be considered to ensure efficient treatment.
Effect of water parameters on temporal distribution and abundance of zooplank...AbdullaAlAsif1
Seasonal abundance of zooplankton in relation to different physico-chemical conditions of Kaptai lake has been studied. A total of four major groups of zooplankton were identified from study area of Kaptai lake during three seasons observation at pre-monsoon, monsoon and Post-monsoon. These four groups were categorized into rotifers, copepods, cladocerans and others (fish larvae, shrimp larvae, insects, mosquito larvae etc.). The mean abundance of group rotifers, copepods, cladoceras and others were 103, 84.67, 38.33 and 41.83 ind. L-1 respectively. The highest group was rotifers in terms of abundance and composition where compositions were recorded 38 % at three season's observation. The lowest group was cladoceras in term of abundance and composition where compositions were recorded 14 %. The air temperature, water temperature, transparency, water pH, DO, BOD5, PO 4-P, NO 2-N, SiO 3-Si, TSS, TDS, Alkalinity ranged between 21 and 27.5C, 23.5 and 31.5C, 0.8 and 3 m, 7.1 and 7.5, 5.72 and 8.58 mg/l, 8.55 and 12.87 mg/l, 3.22 and 4.13 µg/l, 0.992 and 1.19 µg/l, 161.18 and 201.15 µg/l, 0.28 and 0.48 g/l, 0.18 and 0.68 g/l, 40 and 60 ppm, respectively. Margalef richness index (d), Pielou's evenness index (J'), Shannon-Wiener diversity index (H'), Simpson dominance index (λ) are analyzed by Primer V6 software to quantify the collected species. Through same software SIMPER, Cluster analysis also done to compare similarity between season.
Changes in benthic communities in the Middle Atlas springs (Morocco) and thei...Innspub Net
The sources of the Moroccan Middle Atlas suffer not only the effects of anthropogenic pressures, but also those of climate change whose impact is difficult to predict. Our goal is to better understand the succession of processions fauna of the upper Guigou. It is a compendium comparative between the benthic fauna collected towards the end of the years 70 (1979) in the sources Arbalou Abrchane, Tit Zil and the Wadi Guigou. As well as those harvested in the same sites, thirty-four years after. This revealed a significant drop in dissolved oxygen concentration decreased from 7.4 (mg/l) in 1979 to 2.52 (mg/l) in 2015. We have also raised an increase in the workload in chlorides and major elements. Benthic fauna, a significant change in population since 1979, with the appearance and installation of more than a dozen of taxa were identified (Simulium pseudoquinum, Gammarus gauthieri, Phagocata sp., Dugesia gonocephala). Some of these species have become invasive, such as Amphipod crustaceans Gammarus gauthieri, either very abundant as Simulium pseudoquinum. We note the effect “medium” for the direct selection of the species. Other indirect effects due to the reduction of the three dimensional biogenic structures would have limited recognizably State niches by polluo-sensitive species (Ephemeroptera, Heteroptera, Coleoptera and Trichoptera) and could contribute to the total disappearance of all order plecoptera in favour of a dominance of the polluo-tolerant species (Oligochaetes). Over a period of 35 years, there is a deterioration of the health of the aquatic ecosystem studied, a State of art reflected by a decline of the benthic community that lives there.
This document summarizes a study on identifying the limiting nutrient (nitrogen or phosphorus) that controls aquatic productivity in five lakes and one reservoir in Mexico's Mesa Central region. The study involved collecting water samples from the lakes/reservoir during dry and rainy seasons in 2010 to analyze nutrient levels and conduct algal growth bioassays. The bioassays and nutrient ratios suggested phosphorus limitation in some cases and nitrogen limitation in others, with some sites showing seasonal variation or unclear results. The study aimed to determine the common limiting nutrient and compare seasonal variations to past studies, as nutrient limitation can change over time with human impacts.
AQUATIC GENETIC RESOURCES AND CLIMATE CHANGE_CleanPatrick White
This document provides an overview of the importance of aquatic genetic resources in the context of climate change. It discusses how aquatic ecosystems and the organisms they support play a key role in global carbon and nutrient cycles. Aquatic genetic resources underpin global aquaculture and fisheries, which together provide about half of the world's food fish and are important for food security, nutrition, and livelihoods. Climate change poses challenges for these resources and the sectors that depend on them through impacts like warming, acidification, and changes to freshwater availability. The roles of aquatic genetic resources in adapting to and mitigating climate change impacts are discussed.
Similar to Bacterial Numbers, Biomass and Productivity within the Kwa-Zulu Natal Bight: ACEP 11 (20)
This document discusses identifying local copepod species from the Mlalazi estuary in South Africa that can be used as live feed for fish larvae. Currently, South African fish hatcheries rely on imported live feed, but copepods are a desirable natural food source for fish larvae due to their nutrition. This study treated copepods from the Mlalazi estuary with different temperature and salinity levels to determine which species are most robust, as the first step to identifying suitable local copepods that can replace imported live feeds and improve fish larvae production.
S Pillay, Dr. A. J. Smit, Dr Deborah Robertson-Andersson. Submitted to the ninth Scientific Symposium of the Western Indian Ocean Marine Science (WIOMSA) 2015.
Kaveera Singh, Surina Singh, Gan Moodley, Deborah Robertson-Andersson. Presented at the ninth Scientific Symposium of the Western Indian Ocean Marine Science (WIOMSA) 2015.
This study investigated nitrogen pollution levels along the south coast of KwaZulu-Natal, South Africa. It examined three estuaries - Hibberdene (Mhlungwa Estuary), Margate (Kongweni Estuary with WWTP), and Port Edward (Umtamvuna Estuary) - to determine if each was eutrophic. Nitrogen levels were also analyzed at increasing distances from the estuary mouths in associated rocky shore habitats. Statistical analyses found significant differences in nitrogen pollution among the three sites, with rocky shores supplemented by nutrients from estuarine sources. The study recommends monitoring both estuaries and rocky shores to better understand impacts, and developing more wastewater treatment
Deborah Robertson-Andersson, Judy Mann-Lang, Monica Maroun, Shana Mian & Christa Panos. Presented at the Symposium of Contemporary Conservation Practice 2015.
This document discusses the use of rubrics to enhance student scientific writing skills. It provides examples of rubrics used to assess student work in biology, chemistry, geology, and physics. The document outlines benefits of using rubrics such as making learning criteria and standards visible to students. Data is presented comparing student performance and pass rates from 2013 to 2015, finding that use of rubrics corresponded with improved student marks and higher pass rates. However, strikes impacted student performance in 2015 and gains were not consistently observed that year. Overall, the document advocates for the use of rubrics in assessment as part of the teaching and learning process.
The document discusses using a detailed rubric to evaluate student scientific writing skills across four life science disciplines in a marine biology module. A rubric was created using Bloom's taxonomy and applied to assess student reports in 2013, which showed significant grader bias. In 2014, the same rubric was used and found to eliminate bias while students' writing improved with a 22% increase between first and last reports, leading to a 22% rise in pass rates overall compared to the previous year without a rubric.
Copepods are a desired live feed for fish larvae due to their high nutritional value and small size. This study identified robust sub-tropical copepod species from the Mlalazi estuary in South Africa that could be used to feed Dusky Kob larvae. Copepods were subjected to different temperatures from 10-40°C and salinities from 10-40 PSU over 48 hours to determine their tolerance ranges. Identifying local copepod species that can survive a wide range of conditions will help increase fish larvae production and nutrition while decreasing costs compared to imported feeds or those requiring enrichment.
1) The document discusses aquaculture and aquaponics systems for balancing food production, economic development, and environmental impact reduction. It outlines various challenges with aquaculture including institutional failures and lack of infrastructure.
2) Two honors students conducted a study comparing plant growth and fish mortality in goldfish vs koi aquaponics systems, finding koi systems produced greater growth. They also analyzed costs/benefits of the systems.
3) Aquaponics has potential as a "leapfrog technology" but depends on support from government, hatcheries, and a network of suppliers like the electric grid or mobile network.
Aquaponics systems often require production fish like tilapia as a protein source, but this increases costs and complexity. Using ornamental fish instead could increase project success by providing a cheap, easy to cultivate waste source. This study tested a backyard raft aquaponics system using goldfish or koi as the waste source under LED lights or sunlight. Koi fish supported better plant growth than goldfish, and LED lights did not significantly impact growth compared to sunlight. Using ornamental fish is an example of "leapfrog technology" that could make aquaponics more economically viable.
Travis Kunnen, Gan Moodley, Deborah Roberston-Andersson. Presented at the ninth Scientific Symposium of the Western Indian Ocean Marine Science Association (WIOMSA) 2015
Refilwe Mofokeng, Gemma Gerber, Mathew Coote, Sipho Mkhize, Deborah Robertson-Andersson, Gan Moodley. Presented at the Symposium of Contemporary Conservation Practice 2015.
Raeesah Ameen, Gan Moodley, Deborah Robertson-Andersson. Presented at the ninth Scientific Symposium of the Western Indian Ocean Marine Science Association (WIOMSA) 2015.
Gemma Gerber, Thembani Mkhize, Deborah Robertson-Andersson, Gan Moodley. Presented the the ninth Scientific Symposium of the Western Indian Ocean Marine Science Association (WIOMSA) 2015.
Kaveera Singh, Surina Singh, Gan Moodley, Deborah Robertson-Andersson. Presented at the ninth Scientific Symposium of the Western Indian Ocean Marine Science Association (WIOMSA) 2015.
This document presents a novel methodology for separating microplastics (<500μm) from particulate organic matter (POM) in water samples. Current separation methods are inefficient at separating suspended microplastics and POM due to similarities in size and density. The developed method uses a two-phase separation where a non-polar solvent is added to draw microplastics into a separate immiscible layer that can be removed and analyzed. Testing recovered over 90% of fluorescent polyethylene terephthalate and polypropylene microplastics added but only 1% of denser polyethylene terephthalate microbeads. This accurate separation method allows for investigation of microplastic ingestion and effects in marine organisms and ecosystems.
1) The study aims to determine the effects of microplastic consumption and retention in marine fish by examining microplastic settlement times, gut retention times in various fish species, and the physiological impacts of prolonged microplastic consumption.
2) Preliminary results found that smaller microplastics remain bioavailable and are retained in fish guts longer than larger ones, and that microplastics can serve as a delivery mechanism for pollutants by remaining in fish guts for extended periods.
3) Future experiments will examine the impacts of prolonged microplastic exposure on fish physiology and determine if microplastics can pass through the gut lining into tissues.
Following on from a successful presentation to the Reciculation council members earlier in 2004, I was asked to make this presentation which should be titled why abalone farmers should grow seaweeds.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Unlocking the mysteries of reproduction: Exploring fecundity and gonadosomati...AbdullaAlAsif1
The pygmy halfbeak Dermogenys colletei, is known for its viviparous nature, this presents an intriguing case of relatively low fecundity, raising questions about potential compensatory reproductive strategies employed by this species. Our study delves into the examination of fecundity and the Gonadosomatic Index (GSI) in the Pygmy Halfbeak, D. colletei (Meisner, 2001), an intriguing viviparous fish indigenous to Sarawak, Borneo. We hypothesize that the Pygmy halfbeak, D. colletei, may exhibit unique reproductive adaptations to offset its low fecundity, thus enhancing its survival and fitness. To address this, we conducted a comprehensive study utilizing 28 mature female specimens of D. colletei, carefully measuring fecundity and GSI to shed light on the reproductive adaptations of this species. Our findings reveal that D. colletei indeed exhibits low fecundity, with a mean of 16.76 ± 2.01, and a mean GSI of 12.83 ± 1.27, providing crucial insights into the reproductive mechanisms at play in this species. These results underscore the existence of unique reproductive strategies in D. colletei, enabling its adaptation and persistence in Borneo's diverse aquatic ecosystems, and call for further ecological research to elucidate these mechanisms. This study lends to a better understanding of viviparous fish in Borneo and contributes to the broader field of aquatic ecology, enhancing our knowledge of species adaptations to unique ecological challenges.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
The debris of the ‘last major merger’ is dynamically youngSérgio Sacani
The Milky Way’s (MW) inner stellar halo contains an [Fe/H]-rich component with highly eccentric orbits, often referred to as the
‘last major merger.’ Hypotheses for the origin of this component include Gaia-Sausage/Enceladus (GSE), where the progenitor
collided with the MW proto-disc 8–11 Gyr ago, and the Virgo Radial Merger (VRM), where the progenitor collided with the
MW disc within the last 3 Gyr. These two scenarios make different predictions about observable structure in local phase space,
because the morphology of debris depends on how long it has had to phase mix. The recently identified phase-space folds in Gaia
DR3 have positive caustic velocities, making them fundamentally different than the phase-mixed chevrons found in simulations
at late times. Roughly 20 per cent of the stars in the prograde local stellar halo are associated with the observed caustics. Based
on a simple phase-mixing model, the observed number of caustics are consistent with a merger that occurred 1–2 Gyr ago.
We also compare the observed phase-space distribution to FIRE-2 Latte simulations of GSE-like mergers, using a quantitative
measurement of phase mixing (2D causticality). The observed local phase-space distribution best matches the simulated data
1–2 Gyr after collision, and certainly not later than 3 Gyr. This is further evidence that the progenitor of the ‘last major merger’
did not collide with the MW proto-disc at early times, as is thought for the GSE, but instead collided with the MW disc within
the last few Gyr, consistent with the body of work surrounding the VRM.
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/
The binding of cosmological structures by massless topological defectsSérgio Sacani
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
ESPP presentation to EU Waste Water Network, 4th June 2024 “EU policies driving nutrient removal and recycling
and the revised UWWTD (Urban Waste Water Treatment Directive)”
Bacterial Numbers, Biomass and Productivity within the Kwa-Zulu Natal Bight: ACEP 11
1. Travis Kunnena
, Ursula Scharlera
and David Muirb
a
University of KwaZulu-Natal, School of Life Science
b
City of New York University, Medgar Evers College
traviskunnen1982@gmail.com
Bacterial Numbers, Biomass and Productivity
within the KwaZulu - Natal Bight: ACEP II
Introduction
The KwaZulu-Natal Bight is an oligotrophic system which is dependent on both
allochthonous sources of nutrients, such as intermittent upwelling of deeper water and
nutrients supplied by riverine inputs, as well as the autochthonous nutrients supplied by
phytoplankton production, microbial fixation and the recycling of nutrients by the
microbial loop. Heterotrophic bacteria are heavily dependent upon organic nutrient
sources supplied by both allochthonous and autochthonous sources, and as such, the
presence or absence of such nutrient sources can be linked with bacterial numbers,
biomass and productivity. We present here our final results from the research cruises
undertaken by ACEP II during 2010 incorporating a synoptic and a focus survey within
the KwaZulu-Natal Bight.
Materials and Methods
During the synoptic survey, samples were taken throughout the bight in surface water
(surface), close to Chl-Fmax
(F–max), below Chl-Fmax
(intermediate) and above the sediment
(bottom). Samples were fixed with formaldehyde, stained with DAPI and cells were
visualized by epifluorescent microscopy. Automatic counting techniques were used to
reduce investigator bias of cell dimensions. During the focus survey, samples were taken at
four set locations within the bight over two days at surface, F-max and intermediate depths.
To determine heterotrophic bacterial productivity these samples were incubated with
H3
-thymidine, and incorporation into TCA-precipitable macro-molecules was measured.
Numbers(cells.ml-1
)
Surface F - max Intermediate
Figure 1: Data acquired during the synoptic survey for both the summer and winter cruise are
shown as numbers (cells.ml-1
) and biomass (gC.ml-1
) with corresponding ecological zones.
Also included are the sampling depths (m) shown as contour lines.
Biomass(gC.ml-1
)
Discussion and Conclusion
It was proposed that the degree of inorganic nutrient supply to the
phytoplankton resulted in the formation of dissolved organic matter
used by the heterotrophic bacteria resulting in bottom-up control
mechanisms (nutrient limitations) on the bacteria. This is seen by the
decrease in bacterial values with increasing distance from the coast as
well as with increasing depth, where Chl-a concentrations drastically
decrease below F-max. Chl-a concentrations within the euphotic zone
induces bottom-up control mechanisms on the heterotrophic bacteria
directly affecting their numbers, biomass and productivity. Data from
the focus section suggests that bacterioplankton temporal variables
were more top-down (predator) controlled rather than environmentally
influenced resulting in fluctuating variables over time within the studied
area.
Acknowledgements
First and foremost we would like to thank ACEP and the NRF for funding this
project, as well as the captain and crew of the F.R.S. ALGOA. Thanks also go to
Mr. Ander de Lecea for collecting and preparing the first cruise’s productivity
samples, and to Mr. Riaan Rossouw for assistance with the IPP automatic counting
feature.
SUMEMRCRUISE(Jan-Feb2010)WINTERCRUISE(July-Aug2010)
Numbers(cells.ml-1
)Biomass(gC.ml-1
)
Figure 3: Summer cruise bacterial productivity numbers (cells.ml-1
.hr-1
)
and biomass (gC.ml-1
.hr-1
) for the four focus sites. Error bars denote one
Figure 4: Winter cruise bacterial productivity numbers (cells.ml-1
.hr-1
)
and biomass (gC.ml-1
.hr-1
) for the four focus sites. Error bars denote one
Results
Bacterioplankton variables (numbers, biomass and productivity) for both cruises (Fig. 1), were higher
within the photic zone and near riverine influenced waters, with summer showing higher values than
winter. Irrespective of season, bacterioplankton variables decreased with increasing distance from the
coast as well as with increasing depth. Chl-a surface data for both cruises (Fig. 2) shows decreasing
concentrations with increasing distance from the coast with isolated patches of higher concentrations.
Results obtained from the focus section of both cruises (Figs. 3 & 4) showed a significant difference
between seasons for the Thukela Mouth and Richards Bay North focus site, while no difference at the
Durban Eddy.
Fig 2: Surface Chl-a concentrations (mg.m-3
) for the summer (A) and
winter (B) cruise.
A B