Some abstracts written by science students

1. Sediment removal – costs and benefits

Cost-benefit analysis is an approach widely used in the economic effectiveness evaluation of public projects. It helps in decision-making processes to determine the most suitable alternative for a project or policy.

This presentation firstly introduces the basic steps of the cost-benefit analysis and afterwards shows its possible applications to the evaluation of sediment management strategies in reservoirs., By way of illustration, it shows a comparison of two alternatives, sustainable and non-sustainable, which does not include sediment removal. In this way, the economic effect of sediment removal can be expressed. Finally ???, the presentation highlights some of the key parameters influencing the final economical value of both alternatives.

2. Sedimentation velocity due to the radius and density of particles

The Sedimentation of particles from the drainage basin to the bottom of reservoirs may cause serious problems.

Stoke’s Law, derived from particle buoyancy, describes the relationship between sedimentation velocity in a gravity field, and particle density and size. By adding flow velocity to Stoke’s Law, the distance of particle sedimentation is obtained. Applying this new formula to real data, a theoretical model of sediment distribution can be made. Using graphs I will demonstrate that particles of a higher density and bigger size settle faster and in greater distance, and this distance also increaseswith flow velocity and water level.

3. Hydroelectric power plants and their role in our lives

Hydroelectricity refers to electricity generated by hydropower, that isthe production of electrical power through the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global electricity generation.

Hydropower is one of the most environmentally friendly energies. One typesof hydroelectric power plant is built alongside reservoirs. The dams can be used not only for producing electric energy, but they can also prevent smaller floods, can be used for recreational purposes or as a source of potable or process water and are often suitable for river fishing.

4. Laundry and dish washer detergents – do we care?

Laundry and dish washer detergents play an important role in water pollution – including the Brno reservoir. As one of the most significant sources of phosphorus, these detergents have a large impact on the environment, causing eutrophication. This study aims to show and explain how do laundry and dish washer detergents influence the environment and propose or at least inform about possible alternatives. The Next part focuses on how much people are acquainted with the content of detergents that they use in their households and how deep is their general knowledge. We conclude with a brief summary of the European Union attitude towards phosphorus and phosphorus-free detergents.

5. Sources of phosphorus and population

Excess phosphorus is a concern for all ecosystems. In nature, the amount of phosphorus is limited. Its absence limits the growth of plants, fungi and bacteria. Urban areas surrounding Brno reservoir affects phosphorus levels and disrupts the natural equilibrium. Due to human activity the level of phosphorus rises and pollute aquatic ecosystems, including Brno reservoir being no exception. This presentation will review the sources of phosphorus pollution and divide them into categories based on extension. It will also provide basic information about the incorporation of phosphorus into natural matter, and the difficulties that arise from this.

6. Eutrophication

Eutrophication is a serious water pollution problem which lasts for decades. It can be either human-caused or natural and it is caused by nitrogen and phosphates. It is becoming more widespread and, for instance, more than half of the lakes in Europe are euthropic. Eutrophication may cause cyanobacteria blooms, which is a problem with many negative impacts such as a decrease in water quality and the depletion of oxygen. Some species of cyanobacteria may experience an increase in population that negatively affects other organisms. The Negative environmental effect is a/the reduction in biodiversity . Cyanobacteria can also produce cyanotoxins. An example of eutrophication is Brno reservoir where a big amount of cyanobacteria was found/identified? in recent few years.

7. Fertilizers - Both Blessing and a Curse

The mass use of fertilizers in agriculture has been a controversial topic in the past decades. While the amount of fertilizers being applied is increasing due to the high demand food, new norms and restrictions attempt to minimize the drawbacks of releasing these chemicals into the environment. This presentation will review the basic principles of fertilizer functioning, namely providing plants with the key elements, phosphorus and nitrogen. The fate of fertilizers in the environment will also be discussed, with an emphasis on the transport of the chemicals into surface water and the eventual cause of eutrophication.

8. Chemical precipitation of phosphorus

Phosphorus is a chemical compound, which naturally occurs in water bodies. Because of human activity, the phosphorus level increases in water way below the natural limit. This phenomenon induces several detrimental effects on the water environment. Living organisms concentrate phosphorus in much higher concentrations than water itself and utilize it as a building block of their cells. Small fast-growing organisms, such as cyanobacteria and algae, have enough energy to overpopulate in the surplus of phosphorus. This rapid growth leads to an algal bloom. To prevent any algal bloom, it is necessary to knowhow phosphorus can be precipitated from water bodies to re-establish a natural equilibrium. Using our knowledge of the solubility product equation, it is possible to precipitate phosphorus chemically. This Study focuses on the three most-used methods of chemical precipitation of phosphorus from water bodies.

9. Brno reservoir as a place for sport and recreation

This Poster represents Brno reservoir as a place for sport and recreation. Brno reservoir is situated in Brno-Bystrc and as the poster indicates, it is a very popular tourist attraction of Brno. This makes Bystrc is one of the most favourite/popular destinations of Brno. The Aim of this work is to display major its leisure activities and events. It focuses on the spatial analysis of sports and activities, that are offered in the areas close to the lake.

10. Dishwasher and laundry detergents

In this study is defined the composition of the daily use of dishwasher and laundry detergents. the Mechanism of tensides is briefly described. a Summary of commercialy availible detergents has been made. the Commercial name, producer, content of phosphorous and price are arranged in a table. Another part of the study compare two ways of cleaning dishes: dishwasher use and manual cleaning. The Comparasion shows two points of view 1) economy aspects, 2) ecology aspects. It was analysed that using a dishwasher is more economical than manual washing-up. Whenphosphate free detergents are used, there is no negative ecological impact on the natural enviroment.

Screencast videos of notes on each of the above texts

Made using JING

1. http://screencast.com/t/oFjwPqkeTe5V

2. http://screencast.com/t/RsQgfD4H (one corpus use)

3. http://screencast.com/t/Sb9GgUUPbw68

4. http://screencast.com/t/9lcyEPbcTt

5. http://screencast.com/t/ZwKJbiRkN

6. http://screencast.com/t/JAKv6oIbc4Lj

7. http://screencast.com/t/8F1kpmjK0 (2 corpus uses, short)

8. http://screencast.com/t/vE445xyswL

9. http://screencast.com/t/Fi6WirZRyy (1 corpus use)

10. http://screencast.com/t/Ib3VcfPAjI (1 corpus use)