Hasil untuk "River, lake, and water-supply engineering (General)"

Katarzyna Starzec, Emilia Stańkowska, Paulina Supel et al.

The Kalina pond has been well known as a severely degraded area in the Silesia region, Poland. The environmental deterioration results from high contamination of water and bottom sediments with recalcitrant and toxic organic compounds, mainly phenol. The study was aimed at developing a bioremediation-based approach suitable for this type of polluted areas, involving microbiological treatment of water as a key and integral part of other necessary actions: mechanical interventions and the use of physical methods. During the initial biological treatment stage, autochthonous microorganisms were isolated from contaminated samples of water, soil and sediment, then subjected to strong selective pressure by incubation with the pollutants, and finally, cultivated to form a specialised microbial consortium consisting of five extremophilic bacterial strains. Consortium propagation and its biodegradation activity were optimised under variant conditions enabling bacteria to proliferate and to obtain high biomass density at large volumes allowing for the in situ application. After installing aeration systems in the pond, the consortium was surface-sprinkled to launch bioremediation and then both bacterial frequency and the contaminant level was systematically monitored. The complex remediation strategy proved efficient and was implemented on an industrial scale enabling successful remedial of the affected site. Treatment with the specifically targeted and adapted microbial consortium allowed for removal of most organic pollutants within a four-month season of 2022: the chemical oxygen demand (COD) value decreased by 72%, polyaromatic hydrocarbon (PAH) level by 97%, while the content of total phenols and other monoaromatic hydrocarbons (BTEX) dropped below the detection thresholds.

Yuliya A. Zimina, Tatyana A. Shipaeva, Aleksey S. Venetsianskiy et al.

The study of the chemical composition of natural waters used for balneological purposes is a very important task. In addition, this indicator determines the living conditions of living organisms, ensuring the sustainability of ecological systems, which is especially important when considering the problems of small rivers. At the same time, it is important to have an idea not only about the qualitative and quantitative composition of water bodies, but also to study the dynamic processes that lead to changes in the natural environment.

Tadashi Nittami, Masakazu Oishi, Mana Kato et al.

The Eikelboom filamentous bacterial morphotype ‘Haliscomenobacter hydrossis Eis ubiquitous in Japanese and other wastewater treatment plants (WWTPs). However, it is still largely ‘identified Emicroscopically on its distinctive morphology, and only one species Haliscomenobacter hydrossis is recognized currently. Thus, little is known about the true level of phylogenetic diversity among members of this morphotype. Here, using 16S rRNA gene amplicon data we reveal that populations of this morphotype belong to several clades. Fluorescence in situ hybridization (FISH) probes were designed against members of each of these morphotypes, together with a new probe more specific than those currently available to target members of the genus Haliscomenobacter. Japanese municipal WWTPs were surveyed to evaluate the abundances of ‘H. hydrossis Emorphotype using FISH analysis with the existing and newly designed FISH probes. Data showed that some ‘H. hydrossis Emorphotypes appeared to show suppressed growth in biological nitrogen removal processes, although process configuration seemed not to be a critical factor in determining their abundances. Their excessive growth appears to cause activated bulking incidents in WWTPs. These data may assist in extending our currently poor understanding of ‘H. hydrossis Ephylogeny and systematics and provide tools to study its global distribution.

Kamil Karaban, Agnieszka Poniatowska, Anita Kaliszewicz et al.

We compared different net sampling methods for microplastic quantitative collection by sampling different water volumes with nets of different mesh sizes. Sampling covered freshwater lake and reservoir with a significant degree of eutrophication located in Central Poland. The fibres were the main type of plastic collected from sampling sites and constituted 83% of all microplastic particles. Fibres of 700–1900 μm dominated in the samples. The size of mesh affected the amount of fibres collected. Small fibres of 10–200 μm in length were collected using only a fine net of 20 μm mesh size. The total amount of fibres depended on sample volumes; concentrations of microplastics were higher for smaller water volumes. It is likely that clogging with phytoplankton and suspended particles reduced the filtration capacity of the finest nets when large volumes were sampled, which led to an underestimation of microplastic. To our knowledge, this is the first study to provide evidence that the amount of small microfibres depends on mesh size and that the total microplastic abundance in freshwaters in Poland depends on the sample volume. We suggest sampling rather larger than smaller water volumes to assess the level of microplastic contamination more accurately, but clogging, which reduces the filtration capacity of finest nets, should be taken into account when eutrophic freshwater environments are studied.

Enoch Bessah, Abdulganiy O. Raji, Olalekan J. Taiwo et al.

Illegal mining and inappropriate use of agrochemicals have exacerbated surface water pollution in Ghana. The quality of water has changed, and knowledge of their current condition is important for formulating policies to conserve the country's water bodies. This study assessed the quality of surface waters in Ghana's Pra River Basin. A survey of 344 local farmers randomly sampled was conducted and a physicochemical analysis of 33 water samples collected from 25 rivers in the basin. Boreholes are the main source of drinking water for 85% of farmers, and they assessed water quality by its appearance. Rainwater provides over 50% of the water needed by the respondents for domestic use. River water was mainly used for crop production and only secondarily for domestic use. At more than 80% of the sampled sites, pH, Fe and P were above the WHO recommended values, while Pb was exceeded at 30% of the sites. Cu, Hg, As and Fe were above permissible levels for irrigation, especially near the mining areas. The poor quality of river water makes it unusable despite its availability. A more effective and efficient land-use policy focusing on buffer zone protection is recommended to minimise water quality degradation in the basin. HIGHLIGHTS Surface water are mainly used for crop production in the Pra River Basin.; Mercury, Copper, Arsenic and Iron concentration levels exceed the permissible limits for irrigation in mostly mining communities.; Surface water is available but the level of pollution limits its usability.; Sustainable land management practices can reduce rate of surface water pollution in small-scale mining zones.;

Rafael Esferra, José Carlos de Melo Bernardino, Paolo Alfredini

ABSTRACT For cargo handling to be carried out safely and efficiently, port terminals should provide favorable conditions of shelter, thus avoiding excessive movement of moored vessels and mitigating strengths on mooring lines. However, terminals in which the influence of waves, winds or currents provide adverse conditions to keep a vessel moored need to pay attention to the mooring arrangement of the vessels, through studies that guarantee the effectiveness of the system. In this context, small-scale hydraulic physical models are the most accurate tool for simulation of mooring lines plans of vessels, since they can accurately reproduce all the complexity of the hydrodynamics and its interaction with the vessel. This manuscript presents the technique of physical modeling in vessel mooring studies and its application in a case study made for Ponta da Madeira Port Terminal. In a scale model 1:170 was carried out a comparison of two proposed mooring arrangements for the Valemax class bulk carrier, the results of which allowed to define a safe alternative that made the berthing operation feasible during almost 100% of the time.

PENG Jun-tai, ZHANG Qiang, LIU Chun-Ling

Gui-hua Lu, Qian Ma, Jian-hua Zhang

Black water aggregation (BWA) in Taihu Lake is a disaster for the lake environment. It is a phenomenon resulting from water environmental deterioration and eutrophication caused by accumulation of pollutants in the lake, according to research on the water quality, pollutants of BWA, and occurrence mechanisms of BWA. Dead algae are the material base of BWA, the polluted sediment is an important factor for the formation of BWA, and hydrological and meteorological conditions such as sun light, air temperature, wind speed, and water flow are the other factors that may lead to the formation of BWA. Thioether substances such as dimethyl trisulfide are the representative pollutants of BWA. Parameters such as chlorophyll-a, DO, pH, and water temperature are sensitive indicators of BWA. Measures such as algae collection, ecological dredging, pollution control, and water diversion from the Yangtze River to the lake, are effective, and strengthening aeration is an emergency measure to control BWA.

Andres Urrutia Bustos, Ramon Aravena

A study was carried out to study the fate of ammonium in landfill-leachate contaminated groundwater and surface water. A characterization of the concentration and isotopic signature of ammonium in landfills was firstly done, and secondly a plume of contamination rich in ammonium was investigated to evaluate both the fate of the landfill ammonium concentration and its 15NH4 signature along the groundwater flow system and along the course of a creek, both impacted by the landfill leachate. The study showed that the isotopic signature of the landfill ammonium was conserved along the groundwater flowpath despite attenuation of ammonium along the flowpath, and therefore it can be used as a tool for fingerprinting landfill leachate contamination.

Quang-phu Nguyen, Lin-hua Jiang, Qiao Zhu

High-performance concrete (HPC) is stronger and more durable than conventional concrete. However, shrinkage and shrinkage cracking are common phenomena in HPC, especially early-age cracking. This study assessed early-age cracking of HPC for two mixtures using restrained ring tests. The two mixtures were produced with water/binder mass ratio (mW/mB) of 0.22 and 0.40, respectively. The results show that, with greater steel thickness, the higher degree of restraint resulted in a higher interface pressure and earlier cracking. With steel thickness of 6 mm, 19 mm, and 30 mm, the age of cracking were, respectively, 12 days, 8 days, and 5.4 days with the mW/mB = 0.22 mixture; and 22.5 days, 12.6 days, and 7.1 days with the mW/mB = 0.40 mixture. Cases of the same steel thickness show that the ring specimens with a thicker concrete wall crack later. With the mW/mB = 0.22 mixture, concrete walls with thicknesses of 37.5 mm, 75 mm, and 112.5 mm cracked at 3.4 days, 8.0 days, and 9.8 days, respectively; with the mW/mB = 0.40 mixture, the ages of cracking were 7.1 days, 12.6 days, and 16.0 days, respectively.

LIU Wei-dong, ZHANG Xin-feng, JIANG Xing-ke

KE Ze-ming, HUANG Hai-ka

李德新, 黄洪盛

Manoel Nazareno Procópio de Moura

Parte da região do Norte de Minas fica incluída no Polígono das Secas, portanto beneficiada pelos incentivos fiscais e creditícios proporcionados pelo Finor e FNE. A utilização da água subterrânea no Polígono das Secas mineiro começou em 1948 com perfuratriz a percussão movida a vapor do DNOCS. A partir da década de 70 começaram os estudos que alavancaram definitivamente os conhecimentos hidrogeológicos da região. Em junho de 1997, foi levantada a quantia de 153 poços com vazão superior a 100 m3/h e até junho de 1998, o Banco do Nordeste do Brasil havia financiado a perfuração de 159 poços destinados à irrigação de 1.538 ha de frutas e 203 ha de capineira. O IGAM – Instituto Mineiro de Gestão das Águas, em junho de 1998, forneceu uma listagem das outorgas dos poços destinados à irrigação no Norte de Minas. Esses poços, atingem a vazão total de 30.733 m3/h, quantia suficiente de água para irrigar 7.496 ha de banana ao consumo de 4,1 m3/hora/ha.

师福东

杨类琪, 刘小林