River Outfall Research Articles

Eavesdropping on wastewater pollution: Detecting discharge events from river outfalls via fiber-optic distributed acoustic sensing

Wastewater discharge from outfall pipes can significantly impact river water quality and aquatic ecosystems. Effective outfall monitoring is critical for controlling pollution and protecting public health. This study demonstrates a novel distributed acoustic sensing (DAS) approach for detecting wastewater discharge events from outfall pipes located along rivers. Controlled field experiments were conducted in an industrial park river to systematically evaluate DAS performance. DAS detects vibrational signals imparted to suspended fiber-optic cables by turbulent wastewater flows, predominantly within 10–30 Hz, enabling continuous monitoring along entire river lengths. Vibrational power analysis locates outfalls with meter-level accuracy, while time–frequency techniques discern discharge timing and characteristics. Cable type and outfall–fiber separation influence on detection capability was assessed. Thermoplastic-jacketed tight buffer cables optimized detection through enhanced vibrational coupling. Vibrational energy decreased exponentially with separation, highlighting benefits of proximal deployment for sensitivity. However, detection range scales with discharge flow rate. Frequency centroid proved a robust feature with potential for automated discharge identification. Overall, DAS enables high spatiotemporal resolution monitoring to pinpoint concealed outfalls minimally invasively. This positions DAS as a promising tool supporting improved water governance through early pollution warnings and rapid source localization via outfall vibrational signatures emanating across river networks.

Impact of domestic and industrial effluent on marine environment at Karachi Port Trust (KPT) coastal area, Pakistan.

The extent of aquatic pollution of Karachi Port Trust (KPT) coastal area located at the south of Pakistan coast has increased considerably in the last few decades due to unrestricted discharge of sanitary waste. The current study lays emphasis on the identification of vulnerable zones severely impacted by pollution in the KPT coastal area using laboratory monitoring, geospatial techniques, and statistical analysis. During 2019, sampling was conducted along the KPT coastal area, and 54 samples of seawater were collected during pre- and post-monsoon seasons. The outcomes of physical and chemical analysis revealed that the concentrations of BOD (biochemical oxygen demand), COD (chemical oxygen demand), nitrate, phosphate, phenol, cyanide, and oil and grease frequently exceeded the permitted limit of international norms and reached much greater levels. The levels of perilous metals in the seawater samples were in the order Ni>Cr>Cu>Pb>Cd>As in both phases and also reached to elevated levels as a consequence of the indiscriminate discharge of untreated industrial and domestic wastewater. Based on detailed examination during pre- and post-monsoon, six sites near KPT, Lyari River outfall, and Karachi Harbour were identified as highly polluted zones due to heavy discharge of sanitary effluents at these sites. In particular, the industrial zones present in the formal and informal sectors of Karachi are responsible for the deterioration of the KPT coastal area. Therefore, it is advised to design and build a submerged drainage system to transport and distribute massive amounts of treated municipal and industrial waste to the deep open sea in order to minimize the high pollutant levels in these locations.

Assessment of Marine Coastal Water Pollution from Karachi Harbour Pakistan

In Pakistan, marine pollution is a major problem that is caused by the waste from industrial, municipal, agronomy, and oil leak sources. The pollutant loads along with the coastline areas near Karachi is received from terrestrial contaminants including discharges from Karachi Harbour located on the estuary of the Lyari river. Karachi generates 472 Million Gallon per Day (MGD) of wastewater out of which only 55 MGD is treated and the rest is discharged in the sea. The prevailing sewage treatment plants are functioning at reduced capacity due to the insufficient transmission capacity of interceptors. Water sampling was carried out from the Lyari River and five different selected coastal point around Karachi harbour for physicochemical parameters and selected heavy metals. Results show that the Karachi Harbour area is noticeably polluted, whereas; the coastal environment in the vicinity of Karachi is also under the stress of pollution. High COD and BOD5 values were noticed at the Lyari river samples and the sampling locations close to the Lyari river outfall area. The Pb, Cd, Ni, and Hg heavy metals that pollute marine water are found. This situation is due to the discharge of mixed effluents of industrial and domestic wastes as well as dredging, cargo handling, dumping of ship waste and other coastal activities. The highest value of pollution observed at Karachi Harbour which is near Lyari river mouth, where the domestic and industrial effluents with organic and inorganic wastes have a greater influence on the water quality and the marine environment. At present, there is no effective controlling mechanism for industries to treat their waste, nor has any investigation to assess increasing marine pollution been carried out. As a result, there is an adverse impact on fish habitat and mangroves, corrosion of cargo ships, naval vessels and the residents living in the coastal area. Therefore, the government agencies and industrial sectors should work together to avert marine pollution and attain total environmental sustainability.

Assessment of conflicts between mangroves and human occupation in Subaé river outfall between the years 1988 to 2017

Coastal zones fulfill important ecological, social and economic functions. Because soil flooded by tidal variations and due to great variation in salinity. Mangroves cover these regions. They are also a tropical coastal ecological system, always in the lowlands, at the mouths of rivers and estuaries. Despite their important environmental role, mangrove areas have been continuously decreasing worldwide, with an average reduction of 30% in the last 30 years. Thus, this research sought to determine land use and land cover change in low Subaé. With emphasis on Mangrove areas and urban occupation. We used supervised classifications of satellite images to evaluate the changes. We chose images from 1988, 2003, and 2017. And used images from the Landsat series (30m) and an image from the PlanetScope satellite (3m). We validated classifications through the Tau and Geographical Simultaneity concordance measures. We observed that performing the spatio-temporal analysis observing only the variation of areas may not represent the phenomena that occurred. The overall Tau index calculation for the ratings was 0.89. During the period 1988-2017 there was a significant reduction in Agricultural areas, corresponding to around 15% of the study area. Meanwhile, growth of pasture from 24km² to 48Km² and the Urban Zone, occurred over all classes, including mangroves.

The spatiotemporal shore morphological changes at east Bhola Island in Meghna Estuary of Bangladesh’s central coast

This article focuses on the spatiotemporal shore erosion–accretion progression of east Bhola Island, located in the Ganges-Brahmaputra-Meghna (GBM) basin at the mouth of Meghna Estuary on the central coast of Bangladesh. The erosion–accretion in this dynamic coastal region has caused significant morphological changes and frequent shoreline displacement over the last 40 years. This research analyzed 13 LANDSAT satellite images spanning from 1989 to 2018 to evaluate the shoreline change rates for the east face of Bhola Island over the four selected periods, i.e., 1989–2000, 2000–2005, 2005–2010, and 2010–2018. In general, the upstream portion of the east Bhola Island experienced a higher shore erosion rate up to −139 m/year at the northeast face, close to the confluence of the GBM Rivers. At this portion, the Island’s geometric shape caused the stability of the shore vulnerable against the ebb tide-dominated high monsoon GBM River flows. In the interim, the southeast portion of the Island near the Bay of Bengal faced a slower rate of shore erosion up to −40 m/year because the upper part of the Island provided shelter to the downstream portion that diverts and minimizes the downward GBM River outfall flow intensities towards the sea. Construction of barrages on the major upstream rivers resulted in the widening of the Bhola’s adjoining rivers through lean dry periods and increased wet season flows may be liable for a severe shoreline erosion of −171 m/year in 1989–2000. Further, higher annual rainfall and prolonged floods in 1998 and 2004 increased the shoreline erosion rate to −249 m/year from 2000 to 2005. Nevertheless, after considerable erosion from 1989 to 2005, recently implemented and ongoing shore protection works along the east face of the Island declined the erosion rate drastically to −41 m/year, while some sections achieved shore stability in the latest period of 2005–2018.

Assessment of Marine Coastal Water Pollution from Karachi Harbour Pakistan

: In Pakistan, marine pollution is a major problem that is caused by the waste from industrial, municipal,agronomy, and oil leak sources. The pollutant loads along with the coastline areas near Karachi is received fromterrestrial contaminants including discharges from Karachi Harbour located on the estuary of the Lyari river. Karachigenerates 472 Million Gallon per Day (MGD) of wastewater out of which only 55 MGD is treated and the rest isdischarged in the sea. The prevailing sewage treatment plants are functioning at reduced capacity due to the insufficienttransmission capacity of interceptors. Water sampling was carried out from the Lyari River and five different selectedcoastal point around Karachi harbour for physicochemical parameters and selected heavy metals. Results show that theKarachi Harbour area is noticeably polluted, whereas; the coastal environment in the vicinity of Karachi is also underthe stress of pollution. High COD and BOD5 values were noticed at the Lyari river samples and the sampling locationsclose to the Lyari river outfall area. The Pb, Cd, Ni, and Hg heavy metals that pollute marine water are found. Thissituation is due to the discharge of mixed effluents of industrial and domestic wastes as well as dredging, cargohandling, dumping of ship waste and other coastal activities. The highest value of pollution observed at KarachiHarbour which is near Lyari river mouth, where the domestic and industrial effluents with organic and inorganic wasteshave a greater influence on the water quality and the marine environment. At present, there is no effective controllingmechanism for industries to treat their waste, nor has any investigation to assess increasing marine pollution beencarried out. As a result, there is an adverse impact on fish habitat and mangroves, corrosion of cargo ships, navalvessels and the residents living in the coastal area. Therefore, the government agencies and industrial sectors shouldwork together to avert marine pollution and attain total environmental sustainability.

Research On the Change of Rainwater Quality in the Early Stage of River Discharge

The primary rainwater non-point source pollution is one of the main pollution reasons affecting river water quality. Based on the comprehensive analysis of the rainfall data, initial rainwater quality data and catchment area data, this paper obtains the variation rules and pollution characteristics of the initial rainwater quality at different catchment ranges of river outfall, and provides suggestions for the control of primary rainwater non-point source pollution of the target river outfalls. In the target River outlet of this study, the commercial area is the first to reach the peak of COD and ammonia nitrogen in the initial rainwater quality, and the living area is the highest in the initial rainwater COD and ammonia nitrogen concentration. Thus the control measures can be taken for the initial rainwater in the commercial area, and the key prevention and control measures can be taken for the higher concentration initial rainwater in the living area.

Neural Network Implementations on the coastal water quality of Manora channel for the years 1996 to 2014.

Neural Networks is an Important Part of Computational Intelligence, Systems Theory and Signal Processing and finds numerous important applications in Science and Engineering. Sea water quality contaminates due to the severe untreated domestic, sewage and industrial pollutants. Presence of ammonia in seawater causes the deterioration of coastal water in terms of diminution of oxygen levels which suffocates the marine lives, fishes and mangroves. Industrial, sewage and domestic effluents carried by Lyari River contaminate the Manora channel, Karachi. The aim of study is to make the clear and transparent step-wise use of Artificial Neural Networks for the data driven water quality parameters models of Manora channel (Lyari river outfall zone N 24-51-26, E 66-58-01), Karachi (Pakistan) as well as to compare the pollutant contaminant ratio with the national environmental quality standard limits and other sampling sites of Manora channel and southern east Karachi coast. In this study, Manora channel Physico-chemical water quality parameters are assessed by using Artificial Neural Network taking Biochemical Oxygen Demand (BOD), chemical oxygen Demand (COD), Bicarbonates, potential Hydrogen(pH) , Chloride(Cl) as input and Ammonia(NH3)as output. Mean Square Error and R square are used for the model assessments statistical metrics. The computational work has been done by using R-studio. This is also found that Manora channel has the contaminated level of ammonia along the other sampling stations of both southern Karachi coast (N 24-47-03 E 67-08-39) as well as the other sampling site of Manora channel Karachi coast (N 24-50-15, E 66-58-01). In spite of all contamination Ammonia is found to be within National Environmental Quality Standards limits of Pakistan.

A preliminary pollution appraisal of western backwater at Karachi Coastal area

This study aims at preliminary analysis of pollution profile of western backwater. The site is very important from the ecological perspective. The mangrove ecosystem of the study area is of prime significance, whilst the study area is receiving heavy pollution load from Lyari River. The water samples were collected from the pre-designated locations and analyzed for physical and biochemical characteristics. The BOD and COD concentrations of the samples were extremely higher from the environmental and ecological viewpoint. The heavy inorganic and organic load is coming from the domestic and industrial effluents coming from Lyari River. Oil and grease concentrations were also extremely higher in all these sites indicating the hampering of natural purification system of water. The concentration of phenol also indicates the emptying of industrial effluent at the Lyari River outfall. The heavy influx of the nutrients in the form of nitrogen and phosphate represents the problem of eutrophication at the study area. Out of all 7 sites, L-7 was most polluted as it was closed to the Lyari River outfall. The extent of pollution is at the following order L-7 > L-5 > L-6 > L-4 > L-3 > L-2 > L-1.

Foreshore beach sand as a reservoir and source of total phosphorus in Lake Ontario

Many regions around the Great Lakes have been designated Areas of Concern as a result of consistent water quality problems from pollutants like phosphorus and Escherichia coli, which cause eutrophication, beach postings and Beneficial Use Impairments. While foreshore beach sand is a potential reservoir for E. coli, there is less understanding of whether it might also be a reservoir and source of phosphorus for adjacent beach waters. We measured levels of E. coli, total phosphorus and soluble reactive phosphorus at Sunnyside and Rouge Beaches in the Toronto and Region Area of Concern, and stormwater outfalls in the adjacent Humber and Rouge Rivers within their beachsheds. Additionally, we used microbial source tracking assays to detect human and gull fecal contamination. Soluble reactive phosphorus concentrations were highest in stormwater outfalls, with concentrations as high as 556 µg l−1 at an outfall in the Sunnyside beachshed, and 4780 µg l−1 at an outfall in the Rouge beachshed. In contrast, the highest total phosphorus concentrations were typically found in foreshore beach sand pore water and were more associated with gull fecal contamination. Beach sand total phosphorus levels were as high as 10,600 µg l−1 at Sunnyside Beach, although the highest total phosphorus concentration measured (25,600 µg l−1) was in a Rouge River outfall. Concentrations of total phosphorus in outfalls were significantly correlated with concentrations of E. coli in both beachsheds and the human microbial source tracking marker in the Sunnyside beachshed outfalls. These results indicate that stormwater outfalls with sewage cross-contamination can deliver high concentrations of total phosphorus, soluble reactive phosphorus and fecal bacterial contamination to associated beachsheds. Further, similar to E. coli, foreshore beach sand can act as a reservoir of total phosphorus and a source for adjacent water bodies via wave action or groundwater discharge. High phosphorus inputs from beach sand could contribute localized changes to microbial communities and unique eutrophication effects along beach shorelines.

Detection of a Planktothrix agardhii Bloom in Portuguese Marine Coastal Waters.

Cyanobacteria blooms are frequent in freshwaters and are responsible for water quality deterioration and human intoxication. Although, not a new phenomenon, concern exists on the increasing persistence, scale, and toxicity of these blooms. There is evidence, in recent years, of the transfer of these toxins from inland to marine waters through freshwater outflow. However, the true impact of these blooms in marine habitats has been overlooked. In the present work, we describe the detection of Planktothrix agardhii, which is a common microcystin producer, in the Portuguese marine coastal waters nearby a river outfall in an area used for shellfish harvesting and recreational activities. P. agardhii was first observed in November of 2016 in seawater samples that are in the scope of the national shellfish monitoring system. This occurrence was followed closely between November and December of 2016 by a weekly sampling of mussels and water from the sea pier and adjacent river mouth with salinity ranging from 35 to 3. High cell densities were found in the water from both sea pier and river outfall, reaching concentrations of 4,960,608 cells·L−1 and 6810.3 × 106 cells·L−1 respectively. Cultures were also established with success from the environment and microplate salinity growth assays showed that the isolates grew at salinity 10. HPLC-PDA analysis of total microcystin content in mussel tissue, water biomass, and P. agardhii cultures did not retrieve a positive result. In addition, microcystin related genes were not detected in the water nor cultures. So, the P. agardhii present in the environment was probably a non-toxic strain. This is, to our knowledge, the first report on a P. agardhii bloom reaching the sea and points to the relevance to also monitoring freshwater harmful phytoplankton and related toxins in seafood harvesting and recreational coastal areas, particularly under the influence of river plumes.

Abundance and Ecology of EndemicAsterorotalia trispinosafrom the Western Bay of Bengal: Implications for its Application as a Paleomonsoon Proxy

AbstractA total of 97 surface sediment samples were collected from the continental shelf and slope of the western Bay of Bengal to assess the potential application ofAsterorotalia trispinosaas a paleomonsoon proxy. The relative abundance of living as well as total (living and dead)A. trispinosaranges from being absent to a maximum of ∼31%. The highest abundance ofA. trispinosais close to the outfall region of the Ganga‐Brahmaputra Rivers and decreases away from the river mouths. Contrary to that,A. trispinosais rare in front of both the Cauvery and Pennar river outfall regions, in the central part of the western Bay of Bengal. The livingA. trispinosaabundance is the lowest in between two major river systems, viz. Ganga‐Brahmaputra‐Mahanadi and Krishna‐Godavari. The relative abundance of both the total and livingA. trispinosais strongly positively correlated with ambient seawater temperature, and negatively correlated with %Corg and salinity. Based on the spatial distribution, we conclude thatA. trispinosais stenohaline in nature, rather than euryhaline, and further that the increased relative abundance ofA. trispinosaindicates warmer and only marginally hyposaline environment. Even though the ecological preference ofA. trispinosasuggests it as a potential paleomonsoon proxy, the restricted distribution implies limited application.

Diagnosis of the Port and Waterway Area of Itajaí – PWAI (SC): Bases for the Local Marine Spatial Planning (MSP)

Nos últimos anos, a instalação de novos empreendimentos na região da foz do Rio Itajaí-Açu passou por uma forte pressão devido à inserção de novos estaleiros e marinas, além da expansão portuária dos dois lados do estuário. Logo, o uso da zona aquaviária e portuária de Itajaí torna-se mais intenso, consequentemente, essa situação leva a problemas e conflitos, os quais surgem devido à ineficiente aplicação de políticas públicas de planejamento e ordenamento territorial. O presente trabalho realiza um diagnóstico da zona de uso aquaviário e portuário (ZUAP) de Itajaí, a fim subsidiar a gestão integrada local. Para isso, o Planejamento Espacial Marinho (PEM) surge como um instrumento inovador de apoio à gestão, que tem por objetivo ordenar e zonear o ambiente, além de entender os problemas e conflitos, oportunizando mudanças futuras de forma consorciada. A metodologia utilizada baseia-se no Guia da UNESCO, o qual apresenta 10 passos para execução do PEM e constitui-se num processo de natureza adaptativa e contínua. A metodologia adaptada utilizada neste estudo traz uma abordagem de análise territorial de baixo custo e proporciona a integração de visões interssetoriais. A ZUAP se constitui numa zona de abrigo à navegação, o que propicia o desenvolvimento de atividades conflituosas e relacionadas a essa característica. Os municípios que circundam a ZUAP apresentam seu desenvolvimento econômico relacionado diretamente com os setores portuários, pesqueiros, da construção e reparo naval, além do turismo e lazer. O desafio para a política bem-sucedida em PEM no âmbito do estuário do Rio Itajaí-Açú encontra-se na montagem de todas as peças do quebra-cabeça, trazendo a conciliação entre investigação científica e soluções práticas. Por se tratar de uma abordagem holística, este diagnóstico pode ser considerado como o primeiro passo para o desenvolvimento de um plano de uso múltiplo no baixo estuário do Rio Itajaí-Acú.

The allochthonous material input in the trophodynamic system of the shelf sediments of the Gulf of Tigullio (Ligurian Sea, NW Mediterranean)

The organic allochthonous material input in the benthic system of a NW Mediterranean shelf area was studied using a three-pronged approach, focusing firstly on the evaluation of the sedimentary stable isotope ratios and organic matter (OM) composition, then on the OM recycling processes performed by the microbial organisms, and finally on the potential trophic relationships between the macrobenthic organisms. The highest allochthonous signal, indicating continental input, was observed within the 50-m isobath, while at the 80-m isobath the marine signal was higher, pointing to a rather low continental influence approximately 5 km from the shore. Heavier rainfall, often generating abrupt allochthonous inputs by river outfalls, led to a wider spread of fine sediment particles. Carbohydrates were the compounds that best represented the continental input and these compounds were associated with potential recycling activities by microbiota, pointing to the entry of these C-containing allochthonous materials into the microbial food web. The macrofaunal deposit-feeders used sedimentary OM characterised by a continental signature as a food source, although the isotopic ratios of the organisms also pointed to selective feeding on materials that had a marine signature, especially at our offshore sampling stations. Predators fed on deposit- or suspension-feeders, with a potential selection of the latter during the highest inputs of continental materials occurring in winter.

A percepção ambiental, identidade e pertencimento dos moradores do povoado Cabeço, em Brejo Grande/SE, frente às inundações na foz do rio São Francisco

A apropriação dos recursos naturais pela hidrelétrica de Xingó gerou impactos na produção de pescado e de arroz, bem como ocasionou mudanças na foz do rio São Francisco, o que levou à inundação e à extinção do Povoado Cabeço, em Brejo Grande/SE. O presente artigo objetiva analisar a percepção ambiental, a identidade e o pertencimento dos moradores deste povoado e para tanto fez uso de entrevistas semiestruturadas. Constata que, além dos aspectos físicos, degradou-se um modo de vida e essas mudanças fazem perceber a ligação simbiótica que mantêm o homem e o meio ambiente, especialmente com o rio. Essa ligação se dá a partir da compreensão de sua existência e da relação de dependência com o meio ambiente, que é intrínseca ao seu modo de produção, em função da mesma base material. Neste artigo, se deu ênfase às perdas das referências culturais e simbólicas, bem como às perdas das redes de parentesco estabelecidas naquele espaço, identificando-as no contexto das falas dos moradores, de modo que ensaiou-se uma reflexão sobre as estratégias por eles criadas para dar conta da desordem instaurada em seu mundo pessoal e social, esta causada pelo impacto das mudanças ambientais que os atingiram. Dessa forma, esses moradores se recolhem às memórias do passado, seja na perspectiva individual ou na perspectiva de uma memória coletiva, presas exaustivamente ao ontem de suas vidas pela ausência de escolhas ou de poder decidir sobre seus destinos.

Comparsion of some Chemical Parameters of Urban and Industrial Water Discharges Onto the River Lumbardh of Prizren

Abstract: In this paper is described the concept of the monitoring system for water condition and physical - chemical parameters of the water quality. The biggest problem in environmental protection, is the quality of surface water. Complex approach includes physical and chemical analyzes of water of the river Lumbardhi, and those of discharge urban and industrial wastewater. Results from the analysis of the study will be used to manage eco - status in order to prevent negative trends and create a desirable balance of so important ecosystem like the system consisting of Lumbardhi river, yet with preserved biodiversity. The purpose of this paper is to compare the dynamics of river pollution Lumbardhi from urban and industrial discharge water during the same time intervals but different years. As a point of monitoring is selected the source of Lumbardhi L1 Prevall, then there is the point monitoring industrial area L2 and L3 point river outfall that has been marked with L3 Vlashnje. It was executed a monitoring of surface water through their physical - chemical analysis in two cycles: April-May 2012 and April-May 2015 of these parameters. Suspensive dissolved materials, biochemical oxygen consumption, chemical oxygen expenditure and total organic carbon in the source of Lumbardhi river, in the urban area and in the river outfall of Lumbardhi. Through this monitoring, in this paper is made comparison of these above parameters which shows that the results obtained from tests which have been made in Hydro Meteorological Institute in Pristina resulted that there is a considerable pollution of the river Lumbardhi from these pollutants and according to our opinion this comes as a result of not sustainable economic-ecologic development, social-ecologic, eco education and lack of surface treatment and urban sewage, industrial. On the other hand, based on the ecological situation and physic - chemical characteristics of Lumbardhi River during time intervals, it will serve as the starting point for integrated management plans and, if necessary, for programs, measures and environmental protection activities.

Growth of Acropora formosa Fragments in In-situ Coral Nurseries at Polhena Reef, Matara, Sri Lanka

Coral reef are one of the most valuable coastal ecosystems, yet they are under various threats. Present study was to investigate the growth of Acropora Formosa fragments in in-situ coral nurseries of Matara Pollhena reef located on the southern coast of Sri Lanka. Study was conducted between April to November 2014. Eight different sites representing open sea and reef lagoon were selected to compare growth of A. formosa fragments in coral nurseries. Seawater quality parameters such as salinity, water temperature, pH, dissolved oxygen, nitrates, and phosphates were measured in monthly intervals. In addition, sedimentation rate was determined by deploying sediment traps. The highest mean extension growth rate for A. formosa (1.07±0.05 cm per month) was recorded at a site in the reef lagoon close to Nilwala river out fall and lowest mean extension rate (0.20±0.06 cm per month) was also recorded in reef lagoon more southward to the Nilwala river outfall. There was significantly different growth rates among eight sampling sites (t-test, p<0.05). The mean extension growth rates for open sea sites were higher when compared with reef lagoon sites (0.41±0.09 cm per month, 0.72±0.07 cm per month) respectively. The survival rates of coral fragments were ranged from 85.71% to 65.08%. The results highlight that the A. formosa shows differential growth rates in reef lagoon and open sea areas. Further, A. formosa has higher growth rate compared to other coral species and also can withstand higher sedimentation rates. Keywords: Acropora formosa, Coral growth, Coral nurseries, Polhena reef

Autotrophic microorganisms in river outfalls of Lake Elton

For the first time, communities of autotrophic microorganisms in outfalls of seven meso- and hypersaline rivers located in the Eltonsky Natural Park were studied. As a result, 132 species, variants, and forms from six divisions were found. The specific composition of taxa in every watercourse was noted. A correlation between species diversity and salinity levels was not revealed.

Assessing biophysical controls on Gulf of Mexico hypoxia through probabilistic modeling.

A mechanistic model was developed to predict midsummer bottom-water dissolved oxygen (BWDO) concentration and hypoxic area on the Louisiana shelf of the northern Gulf of Mexico, USA (1985-2011). Because of its parsimonious formulation, the model possesses many of the benefits of simpler, more empirical models, in that it is computationally efficient and can rigorously account for uncertainty through Bayesian inference. At the same time, the model incorporates important biophysical processes such that its parameterization can be informed by field-measured biological and physical rates. The model is used to explore how freshwater flow, nutrient load, benthic oxygen demand, and wind velocity affect hypoxia on the western and eastern sections of the shelf, delineated by the Atchafalaya River outfall. The model explains over 70% of the variability in BWDO on both shelf sections, and outperforms linear regression models developed from the same input variables. Model results suggest that physical factors (i.e., wind and flow) control a larger portion of the year-to-year variability in hypoxia than previously thought, especially on the western shelf, though seasonal nutrient loads remain an important driver of hypoxia, as well. Unlike several previous Gulf hypoxia modeling studies, results do not indicate a temporal shift in the system's propensity for hypoxia formation (i.e., no regime change). Results do indicate that benthic oxygen demand is a substantial BWDO sink, and a better understanding of the long-term dynamics of this sink is required to better predict how the size of the hypoxic zone will respond to proposed reductions in nutrient loading.

Risk assessment of coastal erosion of Karasu coast in Black Sea

Coastal erosion occurs as a result of human ac tivity and natural phenomena. Coastal erosion causes significant economic and ecological problem. There is continuing serious coastal erosion along the Karasu coastline. This study reports on the process of determining the extent of the coastal erosion using satellite images from different time periods and the analysis of the risk to the environment. The change in the coastline over a 26-year period from 1987 to 2013 was determined using satellite images. In this study, significant coastline movements were detected for a 26-year period. For this study, the Karasu coastline was subdivided into 7 sections for analyses the coastal erosion risk. The risk of each section can be determined by using the classic risk. The results showed that both sides of the river outfall and the coastline have a moderate risk level with the area of the breakwater has a low risk.