Phosphorus (P) inputs into water reservoirs are the primary cause for accelerated eutrophication affecting water quality. Attempts are underway to regulate inputs originating from concentrated animal feeding operations (CAFOs). The purpose of this research was to relate runoff dissolved (DP) and total P (TP) losses to site-specific characteristics from plots in CAFOs and compare them to their corresponding risk assessment using the Texas Phosphorus Index (PI). Initial studies showed that soil test P (STP) methods used in Texas by inductively coupled plasma were highly reproducible regardless of manure source or application rate. However, NH4OAc-EDTA extraction efficiency was increased with respect to other methods as soil conditions became less acidic, probably due to dissolution of the greater portion of Ca-bound P resulting in STP values that could be three times greater than those of Mehlich III for the same soil. Surface application of dairy manure to high pH soils were positively correlated to STP at various soil-sampling depths down to 15 cm. First order linear relationships between STP values and DP concentrations in runoff were statistically significant for extraction methods and sampling depths but were different among different soils under neutral to calcareous conditions. Attempts to reproduce this relationship on fields that received periodic applications of manure or effluent with various incubation periods failed, although there was a single highly significant relationship between STP and runoff DP for different soils when soil conditions were acid ( pH<6.5) with various sampling depths. Analyses of NH4OAc-EDTA extractable soil elements showed Mg was significantly correlated to DP concentration across various management and soils, indicating that Mg-bound P is a major component controlling P release into runoff. Use of the Texas PI reflected vegetation type closely, with grass-covered sites averaging the lowest risk rating, and having the lowest DP and TP losses, while conversely tilled sites had the highest. However, overall relationship was poor when estimates for erosion rates were used due to experimental design limitations. Use of measured erosion rates for plots and inclusion of extractable Mg improved correlations between PI rating to DP and TP losses, with r2 ranging from 0.60 to 0.87.

Water is essential for our daily life. Despite this, much of our water has become polluted and nutrient-enriched. One main factor contributing to the problem are private sewers. In total, there are nearly 1 million private sewers in Sweden, which represent one of the largest point sources of nitrogen and phosphorus. A survey was carried out to investigate the status of private sewers at Källsjön, Sollefteå municipality. In addition, four municipalities around Sollefteå have been interviewed about the implementation of legislation concerning private sewers. The study shows that sewers around Källsjön are seemingly in relatively good condition. However, 36% of the polled property owners have drains that are over 20 years old, and the function of these drains can be questioned. Interestingly, many of the surveyed property owners do not even know how old their drains are and what type of facility they have. Three of four interviewed municipalities are currently not performing any active control of private sewers. All municipalities provided information to property owners regarding current legislation. The study suggests that municipalities should act proactively to establish comprehensive inventories, a first step towards raising the standard of the individual sewers.

Coastal communities will be most affected by global climate change and are important to study to understand current and future ecological processes. The current model for global climate change predicts a change in rainfall, which will alter the salinity of coastal systems. Given the presence of eutrophication in many coastal waters, it is important to understand the effects that this increase in nutrients, coupled with changes in salinity, will have on these communities. This study was conducted to understand the effect of salinity increase on the growth and herbivory of the black mangrove, Avicennia germinans, in the presence of increased nutrients. Explicitly, the effects of changing salinity (high, medium, and low) were coupled with fertilizer additions of nitrogen, phosphorus, both, or no fertilizer. Nutrient enrichment differentially affected the growth and herbivory of the plants between salinity zones. The medium salinity zone consistently produced the greatest increases in growth and herbivory. Added nutrients did not have an effect on growth in the low salinity zone. However, added nitrogen increased some growth variables in the medium salinity zone and added phosphorus increased some growth variables in the high salinity zone. Phosphorus also increased herbivory. The results point to diverse processes acting along the salinity gradient. There appears to be differential N- and P-limitation along the gradient. Additionally, the growth differences indicate abiotic and biotic limitations across the salinity gradient, with debilitating salinity acting in the high salinity zone and competition acting in the low salinity zone.

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Vandens ekologinė reikšmė biosferoje yra labai didelė. Klaipėdoje, kaip ir kituose miestuose yra surenkama daug nutekamųjų vandenų. Buitinių nutekamųjų vandenų sąlygiškai pastovi teršalų sudėtis. Daugiausia tai augalinės ir gyvulinės kilmės organinės medžiagos. Nutekamųjų vandenų valymo tikslas yra išvalyti nuotekas, atitekančias į valymo įmonę taip, kad jos neužterštų priimančiųjų vandens telkinių. Į vandens telkinius patenkantis per didelis arba nesubalansuotas biogeninių medžiagų (ypač fosforo ir azoto) kiekis sukelia eutrofikaciją – vandens telkinių biologinio produktyvumo didėjimą. Didelę problemą nutekamųjų vandenų valymo įrenginiuose sudaro bendrojo azoto išvalymas, tam dažniausia naudojamas biologinis azoto šalinimo būdas. Cheminis nusodinimas ar biologinis valymas yra tarp paprasčiausių technologijų fosfatų kontrolei palaikyti nuotekose. Buvo apskaičiuota, jog Klaipėdos miesto nuotekų valymo įrenginiai išleisdami bendrąjį azotą į Kuršių marias kas metai padaro 33408 Lt. žalą Kuršių marioms, o išleisdami bendrąjį fosforą – 36435 Lt žalą. Atlikti nitrifikacinės ir denitrifikacinės zonos skaičiavimai parodė, kad nitrifikacinę zoną reikėtų padidinti nuo 7140 m3 iki 11424 m3, o denitrifikacinę – nuo 16197 m3 iki 28181 m3, o norint sumažinti bendrojo fosforo kiekį išvalytose nuotekose iki normatyvinių koncentracijų, tūrį reikėtų padidinti nuo 3152 m3 iki 3418 m3. Padidinus nitrifikacijos ir denitrifikacijos zonas santykinė žala pagal bendrą azotą sumažėtų nuo 33408 Lt... [toliau žr. visą tekstą] / The biggest problem in the municipal wastewater treatment plans is nitrogen and phosphorus removal from wastewater. These materials are very important elements that have attracted much attention because of their ability to cause eutrophication in bodies of water. For biological nitrogen removal usually are using nitrifikacion and denitrification techniques. Techniques presently employed for reducing the phosphorus levels in effluents cross the boundary between biological and chemical/physical methods. The main aim of the transaction of the University is to analyse the Klaipėda`s wastewater treatment plant’s work of removal total nitrogen and total phosphorus, and culculate parameters of equipment, to reach a normal rate of general nitrogen and phosphorus removal. In this transaction are used 2003-2006 year data of Klaipėda wastewater treatment plant. By analyzing this problem we came to decision to enlarge the size of nitrification zone from 7140 m3 to 11424 m3 and denitrifikacion zone from 16197 m3 to 28181 m3. These actions helps to reduce the discharge values and to meet requirement parameters. That way we would decrease damage to Kuršių lagoon from 33408 Lt. to 28866Lt. per year. As we analysed the Klaipėda’s wastewater cleaning equipment work, and we received, that the damage made to the Kuršių lagoon is 36435 Lt per year. Then we made the decision that we need to enlarge the size of the anaerobic zone from 3152 m3 till 4670 m3, if we want to minimize the general... [to full text]

This study investigates effects of eutrophication on settlement, abundance, mortality and community structure of soleractinian corals on fringing reefs on the west coast of Barbados, W.I. Juvenile abundance was lower, but juvenile size larger, on eutrophic than less eutrophic reefs. The lower abundance results at least in part from a higher juvenile mortality on eutrophic reefs. Algae were more abundant and grazers (Diadema antillarum and herbivorous fish) less abundant on eutrophic reefs. Juvenile community structure on all reefs, and adult community structure on eutrophic reefs, was dominated by type 1 corals (high recruitment, high natural mortality). Type 2 corals (low recruitment, low natural mortality) were common in adult communities on less eutrophic reefs. Settlement of coral recruits on artificial substrates was lower on more eutrophic reefs.

South Africa is a semi arid country and the provision of water clean water to a steadily growing population is currently one of the major challenges facing governmental organisations. Water resources in South Africa are subject to many forms of pollution. resulting in eutrophication and salinisation. Hence, there is a need to monitor chemical and organic pollution in South African rivers. Chemical monitoring is expensive and not all the elements of water quality can be monitored and measured in a particular sample. The synergistic effects of water quality determinants cannot be demonstrated if only the chemical composition of a water resource is monitored. Biological monitoring can provide a rapid indication of water quality and at a lower cost than traditional monitoring. Organisms within a river are exposed to all water quality variables present in a system and can provide an integrated reflection of the health of their environment. Diatoms are found in all aquatic ecosystems and have demonstrable responses to many of the elements of water quality that have been identified as causing aquatic pollution. These elements include total dissolved solids, pH and plant nutrients such as nitrates and phosphates. The relationship between the structure of a given diatom community and the water quality to which the community is exposed, has lead to the development of several indices of water quality. Diatom indices of aquatic pollution have been developed in France, Belgium, Germany, Britain and Japan. Existing diatom indices have been tested for use in Finland, Poland, Britain, the Himalayas and South America. Several diatom indices were tested in this study for application in the Vaal and Wilge Rivers. The tested diatom indices correlated well with measured water quality variables such as pH and the chemical variables responsible for eutrophication and salinisation. The demonstrated correlations were comparable to those demonstrated by European authors. Several indices proved successful in indicating general water quality, namely the Biological Diatom lndex (BDI), the Specific Pollution sensitivity lndex (SPI) and the Generic Diatom lndex (GDI). The Eutrophication and Pollution lndex (EPI) successfully indicated levels of plant nutrients together with the ionic composition measured at various sites in the Vaal and Wilge Rivers. It is recommended that these indices be further tested in different regions within South Africa. / Thesis (M. Omgewingswetenskappe)--North-West University, Potchefstroom Campus, 2004.

The acidification and metal contamination of freshwater resources are major environmental concerns in many areas, with Sudbury (Ontario, Canada) having been amongst the most severely impacted. Many scientific investigations have examined the effects of these environmental stressors on aquatic systems, but relatively little is known about the biological recovery process following smelter emission reductions. Therefore, paleolimnological techniques were utilized to determine if diatom and scaled chrysophyte assemblages have recovered toward their pre-disturbance conditions as a result of reduced anthropogenic inputs. Pre-industrial algal assemblages were primarily dominated by circumneutral to alkaline and pH-indifferent taxa. However, there was a shift toward acid-tolerant species in all study lakes with the onset of open pit roasting and smelting operations. Coinciding with emission reductions, scaled chrysophyte assemblages in two of the three study sites have shown evidence of biological recovery. Given the population growth of the city of Sudbury over the last century, and the lack of scientific information regarding cultural eutrophication trends in the region, paleolimnological techniques were also used to track long-term biological changes within diatom assemblages related to cultural disturbances. Historically, oligotrophic diatom taxa primarily dominated the algal assemblages in each of the four study lakes. With the onset of urban environmental stressors there was a shift toward taxa which thrive in more productive systems. In addition, diatom assemblages appear to track increased lakewater pH through time. Finally, geochemical analysis tracked the increase in copper and nickel concentrations in lake sediment with the onset of open pit roasting and smelting activities and the subsequent decline in concentration with emission controls. Metal concentrations in recently deposited lake sediments remain elevated compared to pre-industrial concentrations. Paleolimnological studies comparing pre- and post-disturbance algal assemblages are of interest to lake managers as these data will aid in setting realistic mitigation targets for freshwater systems impacted by acidification, cultural eutrophication, and metal contamination, and will help gauge biological recovery mechanisms. Furthermore, this study provides insight in to the role other environmental stressors (e.g., climate change) may play in the biological recovery process. / Thesis (Master, Biology) -- Queen's University, 2008-07-10 12:04:59.828

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