EFEKTIVITAS ALUMUNIUM SULFAT DALAM MENGURANGI KEKERUHAN AIR PADA UJI JAR TEST PT. HANARIDA TIRTA BIRAWA SIDOARJO

Carbon and nitrogen stable isotopes in suspended matter and sediments from the Schelde Estuary

The aim of this paper was to study the influence of environmental characteristics of the Mediterranean climate on seasonal variability of particulate organic matter abundance in a mountain stream. Coarse and fine fractions of both suspended and benthic particulate organic matter were determined on 14 occasions between February 1998 and November 1999 in a second‐order Mediterranean stream in Central Spain (Arroyo Mediano). Temporal variability of suspended organic matter followed a seasonal pattern, attributed to litter‐fall inputs, instream processing, and the hydrological regime. Suspended organic matter (SOM) and its seasonal variability fall well within the range reported for streams in temperate non‐Mediterranean deciduous forest. However, we found no seasonal trend in benthic organic matter (BOM) storage, and it seems that the amount of BOM remained fairly constant throughout the year. Reach retention (evaluated as the ratio between BOM and SOM per m2) was higher in summer during reduced stream flow, mainly due to coarse particulate organic matter storage. These observations do not differ from those reported for other headwater streams in temperate forested biomes, from which we conclude that there was no evidence of a Mediterranean influence on particulate organic matter dynamics in the Mediano stream, nor probably in other headwater Mediterranean streams. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Dispersal of suspended matter in Makasar Strait and the Flores Basin

Abstract. Intra-annual variations of δ13C and δ15N of water-column suspended particulate organic matter (SPOM) have been investigated to understand the biogeochemical cycling of C and N in the Western Continental Shelf of India (WCSI). The key issues being addressed are: how the δ15N of SPOM is affected by seasonally varying processes of organic matter production and respiration and how it relates to the δ15N of sedimentary organic matter that appears to show a decreasing trend despite an apparent intensification of seasonal oxygen deficiency over the past few decades? A secondary objective was to evaluate the sources of organic carbon. Elemental carbon and nitrogen concentrations, C/N ratios in SPOM, along with ancillary chemical and biological variables including phytoplankton pigment abundance were also determined on a seasonal basis (from March 2007 to September 2008), with the partial exception of the southwest (SW) monsoon period. The results reveal significant shifts in isotopic signatures, especially δ15N, of SPOM before and after the onset of SW monsoon. Very low δ15N values, reaching a minimum of −4.17 ‰, are found during the pre-monsoon period. Our results provide the first direct evidence for the addition of substantial amounts of isotopically light nitrogen by the diazotrophs, especially Trichodesmium, in the region. The δ15N of SPOM is generally lower than the mean value (7.38 ‰) for surficial sediments, presumably because of diagenetic enrichment. The results support the view that sedimentary δ15N may not necessarily reflect denitrification intensity in the overlying waters due to diverse sources of nitrogen and variability of its isotopic composition. The observed intra-annual variability of δ13C of SPOM during the pre-monsoon and post-monsoon periods is generally small. Phytoplankton production and probably species composition could drive some of the observed changes. The largest changes (depletion of δ13C and increase in C/N) appear to occur during the pre- and post-monsoon seasons, presumably through episodic deposition of terrestrial organic matter from the atmosphere. During the SW monsoon, when a large input of terrestrial organic matter is expected through runoff from land, the C/N ratio remains low, but significant difference is observed between δ13C data in 2007 and 2008. Inputs of soil organic matter that may have elemental and isotopic signatures different from those of the conventional (C3 plant derived) organic matter could explain the constancy of the C/N ratio.

The distribution of marine birds relative to water clarity was examined in the nearshore waters of Monterey Bay, California. I conducted nine at-sea surveys in 1999 and 2000 and simultaneously recorded water clarity and the density of five taxa of marine birds. Among plunge-divers, Forster's Terns (Sterna forsten) occurred more frequently than expected over turbid water ( 5 m Secchi depth). Turbidity in Monterey Bay may be caused by suspended organic matter, including phytoplankton, during summer and fall. Forster's Tern may prefer such areas because small fish are likely to occur near this potential food source. Brandt's Cormorants probably rely on vision to catch fish near the bottom and turbid water may reduce available light and limit visual acuity. The distribution of Brown Pelicans (Pelecanus occidentalis), Western/Clark's Grebes (Aechmophorus occidentalis!clarki?), and Marbled Murrelets (Brachyramphus marmoratus) did not appear to be influenced by turbidity levels, indicating that some seabirds use marine habitats with a wide range of water clarities.

Lake Sentani has an area of ​​about 9,630 ha and is located at an altitude of 72 m above sea level. Residents who live on the shores and shores of the lake, use the lake water for bathing, washing and latrine purposes. They also use it as raw water for drinking water and also as a means of transportation and even throw household waste into the lake water. There are 5 (five) rivers as the inlet, namely the Hawaii, Yamolo, Klandeli, Dofroko and Hobay rivers and there is one estuary, the Djaifuri River which is located in the east (Puay area). This study aims to determine the index of each water quality parameter and the total index of water quality. The water quality index parameters studied were; DO, Fecal coliform, pH, BOD, Temperature, Total Sulfate, Nitrate-N, Turbidity and Total Dissolved Solid (TDS). Sampling was carried out at 3 (three) sample points (stations) namely the mouth of the Haway River (Ifale Sentani), the middle of the lake (Ayapo Sentani) and the Upper Jaifuri River (Puay Yoka). Determination of the Total Water Quality Index is calculated using the National Sanitation Foundation's Water Quality Index (NSF-WQI) method for both Lake Sentani water and the total standard water quality index. The test results of each parameter are compared with the Class 1 Water Quality Standards Government Regulation of the Republic of Indonesia Number 22 of 2021 concerning the Implementation of Environmental Protection and Management. The results obtained from the research at 3 (three) research stations turned out that station 1 obtained an index of 44.24 and station 3 obtained an index of 46.60 both classified as Bad (bad), station 2 obtained an index of 51.42 classified as Medium (medium), while the standard water quality class 1 obtained a quality index of 47.24 classified as Bad (poor) too. Thus, when compared with the standard water quality index of class 1, what meets the requirements as raw water for drinking water is lake water at station 2 (Ayapu Sentani) where the index value is greater than the quality standard.

Feeding strategies in symbiotic and asymbiotic thyasirid bivalves

AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 69:211-221 (2013) - DOI: https://doi.org/10.3354/ame01641 Community composition and extracellular enzyme activity of bacteria associated with suspended and sinking particles in contrasting arctic and sub-arctic marine environments Tobias Tamelander* Department of Arctic and Marine Biology, University of Tromsø, 9037 Tromsø, Norway Present address: Institute of Marine Sciences, CSIC, Pg Maritim de la Barceloneta 37-49, 08003 Barcelona, Catalonia, Spain *Email: tobtam@gmail.com ABSTRACT: Heterotrophic bacteria contribute to controlling the oceans? biological carbon pump by solubilising organic particles and by using the dissolved organic matter for growth. To better understand how bacteria colonise and degrade vertically exported organic matter, spatial and temporal variations in the bacterial community composition (BCC) and cell-specific extracellular enzyme activity were investigated in water column samples and in sinking material collected by short-term deployed sediment traps in the Barents Sea (Arctic Ocean) and in a North-Norwegian fjord. Denaturing gradient gel electrophoresis showed that both the suspended and sinking BCC differed among locations (Arctic Water, Atlantic Water and fjord) and with time (summer vs. autumn in the fjord). Within stations, the BCC differed between shallow (20 to 50 m) and deep (120 or 200 m) suspended samples. The sediment traps revealed no depth-related difference but had high similarity to the shallow suspended samples, indicating that the exported community largely derived from suspended particles in the upper mixed layer and that little new colonisation or succession of the resident community took place during transfer to depth. Bacteria in the sediment traps tended to have higher enzyme activities compared to suspended bacteria, likely reflecting a response to aggregation and different composition (carbon, nitrogen and chlorophyll) of suspended and sinking organic matter. While the present study demonstrates that particle export from the surface layer contributes to microbial diversity in the deep sea, future studies using high taxonomical resolution are required to further evaluate the importance of this dispersal pathway. KEY WORDS: Marine particles · Sediment traps · Bacterial community composition · DGGE · Extracellular enzyme activity · Arctic Ocean · Barents Sea · Fjord Full text in pdf format PreviousNextCite this article as: Tamelander T (2013) Community composition and extracellular enzyme activity of bacteria associated with suspended and sinking particles in contrasting arctic and sub-arctic marine environments. Aquat Microb Ecol 69:211-221. https://doi.org/10.3354/ame01641 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 69, No. 3. Online publication date: July 04, 2013 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2013 Inter-Research.

There is a global need for optimizing the use of water that has resulted from increased demand due to industrial development, population growth, climate change and the pollution of natural water resources. One of the solutions is to use reclaimed water in industrial applications that do not require water of potable quality, such as cooling water. However, for cooling water, (treated) wastewater’s hardness is too high, apart from having a high load of suspended solids and organic matter. Therefore, a combination of softening with ceramic micro-filtration was proposed for treating wastewater treatment effluent containing fouling agents for potential use in industrial cooling systems. The effectiveness of the softening process on model-treated wastewater with calcium hydroxide in the presence of phosphate and sodium alginate was first evaluated using jar tests. Furthermore, membrane fouling was studied when filtering the softened water. The results showed that the inhibition of calcium carbonate precipitation occurred when inorganic substances, such as phosphate and organic compounds, were present in the water. The fouling of the membranes due to sodium alginate in water was only slightly negatively affected when combined with softening and phosphate. Therefore, this combination of treatments could be potentially helpful for the post-treatment of secondary effluent for cooling systems.

Biogeochemistry of a tropical river affected by human activities in its catchment: Brantas River estuary and coastal waters of Madura Strait, Java, Indonesia

Developing a semi-analytical algorithm to estimate particulate organic carbon (POC) levels in inland eutrophic turbid water based on MERIS images: A case study of Lake Taihu

Perspectives on provenance and alteration of suspended and sedimentary organic matter in the subtropical Pearl River system, South China

Soils of tropical regions account for ca. 30 % of the terrestrial organic carbon pool. Present-day fires, deforestation and land use changes enhance soil erosion and soil organic matter mineralization, increasing as much the CO2 flux to the atmosphere and reducing the efficiency of organic carbon storage in soils. This chapter presents the results of several isotopic studies carried out on two cultivated watersheds with steep slopes located in tropical regions (Venezuela, Laos) in order to better: 1) link the erosion status and the organic carbon content of cultivated soils by coupling 137Cs and total organic carbon measurements; 2) constraint the source of suspended organic matter during flood events by monitoring the composition of suspended loads in runoff and stream flows with d15N and d13C measurements and; 3) evaluate the impact of a water reservoir set up at the outlet of a watershed on suspended organic carbon fluxes generated by erosion. The redistribution pattern of fallout 137Cs and the soil organic carbon content in the first 30 - cm layer of cultivated soils of the Houay Pano catchment (Laos) are significantly linked. A common process apparently relates the soil erosion status with the amount of organic matter contained in the topsoil horizons. However, the budgets based on soil organic carbon depletion trends are higher than those derived from 137Cs soil erosion rate models. This difference provides evidence for additional organic carbon losses, most likely controlled by mineralization of soil organic matter and dissolved organic carbon release by runoff. The d15N composition of fine-sized suspended organic matter transported by runoff and stream flows during flood events on the Rio Bocono watershed (Venezuela) highlights the contribution of particulate organic carbon derived from incisive erosion of organic matter bearing rocks (“fossil” organic carbon) of the geological basement (i.e.: shales and argillaceous rocks of the river banks). The extent of “fossil” organic carbon release depends on the intensity of the flood event. During an intense event with a return period of 10 years, the contribution of “fossil” organic carbon to suspended sediments was approximately equivalent to that of soils sensu stricto Monitoring the composition of fine (<50 µm or <200 µm) size suspended organic matter with d13C and d15N measurements during flood events also indicates that the transport of particulate organic matter is conservative at different scales for most of the stream flow, providing soil organic carbon specific erosions in the same order of magnitude. The extent of organic carbon transport in the hydrographic network can be thoroughly reduced by water reservoirs set up at the outlet of the watersheds. For the Pena Larga water reservoir, sedimentary accumulation and in-situ mineralization processes reduced by ca. 94 % the organic carbon outflow generated by erosion on the watershed.

Models of particle density and of organic carbon and chlorophyll-a intraparticle concentration were applied to particle size distributions and particle real refractive index distributions determined from flow cytometry measurements of natural seawater samples from a range of UK coastal waters. The models allowed for the estimation of suspended particulate matter, organic suspended matter, inorganic suspended matter, particulate organic carbon, and chlorophyll-a concentrations. These were then compared with independent measurements of each of these parameters. Particle density models were initially applied to a simple spherical model of particle volume, but generally overestimated independently measured values, sometimes by over two orders of magnitude. However, when the same density models were applied to a fractal model of particle volume, successful agreement was reached for suspended particulate matter and both inorganic and organic suspended matter values (RMS%E: 57.4%, 148.5%, and 83.1% respectively). Non-linear organic carbon and chlorophyll-a volume scaling models were also applied to a spherical model of particle volume, and after an optimization procedure achieved successful agreement with independent measurements of particulate organic carbon and chlorophyll-a concentrations (RMS%E: 45.6% and 51.8% respectively). Refractive index-based models of carbon and chlorophyll-a intraparticle concentration were similarly tested, and were also found to require a fractal model of particle volume to achieve successful agreement with independent measurements, producing RMS%E values of 50.2% and 45.2% respectively after an optimization procedure. It is further shown that the non-linear exponents of the volume scaling models are mathematically equivalent to the fractal dimensionality coefficients that link cell volume to mass concentration, reflecting the impact of non-uniform distribution of intracellular carbon within cells. Fractal models of particle volume are thus found to be essential to successful closure between results provided by models of particle mass, intraparticle carbon and chlorophyll content, and bulk measurements of suspended mass and total particulate carbon and chlorophyll when natural mixed particle populations are concerned. The results also further confirm the value of determining both size and refractive index distributions of natural particle populations using flow cytometry.

δ 15N and δ 13C dynamics of suspended organic matter in freshwater and brackish waters of the Scheldt estuary