Forum Free Mp3 Ringtones Strona Główna Free Mp3 Ringtones
Free Mp3 Ringtones. Thousands of Free Mp3 Ringtones in MIDI polyphonic, MP3 and AMR format.
 
 FAQFAQ   SzukajSzukaj   UżytkownicyUżytkownicy   GrupyGrupy   GalerieGalerie   RejestracjaRejestracja 
 ProfilProfil   Zaloguj się, by sprawdzić wiadomościZaloguj się, by sprawdzić wiadomości   ZalogujZaloguj 

The Drain Game

 
Napisz nowy temat   Odpowiedz do tematu    Forum Free Mp3 Ringtones Strona Główna -> Forum testowe
Zobacz poprzedni temat :: Zobacz następny temat  
Autor Wiadomość
txijle789




Dołączył: 30 Sty 2011
Posty: 455
Przeczytał: 0 tematów

Ostrzeżeń: 0/5
Skąd: England

PostWysłany: Pon 12:49, 09 Maj 2011    Temat postu: The Drain Game

The Drain Game
Drainage problems can best be avoided if grounds managers and greenkeepers understand their soil conditions,[link widoczny dla zalogowanych], and know how to diagnose and treat any problems that occur through excess water.Too often, pipe drainage systems [link widoczny dla zalogowanych] are installed automatically, without enough thought being given to both the soil physics of water movement and alternative methods.Soil is made of minerals originally derived from rock and organic matter taken from vegetation, water and air. Most soils in the UK have formed on top of glacial or alluvial secondary deposits, which is frequently boulder clay derived from glacial erosion and deposition. However, the original derivation of all this material is from rock.
This is a measure of the relative proportions of sand, silt and clay in a soil. Soils are often classified according to their texture, and the texture of a soil often provides a fair indication of how it will drain. The soil texture triangle [link widoczny dla zalogowanych] is used to classify a soil based on the relative percentages of sand, silt and clay.FailedDrainage2Structure is a term that describes the way in which the individual soil particles join together to form larger aggregates. A well structured soil is usually characterised by an intensive system of small aggregates or crumbs, gradually leading into larger blocks further down the soil profile.Well structured soils are established on sites that have been left undisturbed for many years. The smaller particles in a soil form aggregates under the influence of clay, organic matter, earthworm activity and grass root activity. Poorly draining soils have often been badly over used and compacted.Water moves through soil in the spaces between the soil particles. These are called the pores. In a soil with a high clay and/or silt content, the pore spaces are very small; the pore spaces are usually much larger in a sand dominated soil. A well structured soil contains a system of inter-connected very large pores that enables efficient water movement.Downward water movement is faster in a soil where the pore spaces are large, hence sandy soils drain faster than clay/silt soils, and well structured soils drain faster than poorly structured soils.
Compaction reduces pore size and causes deterioration in structure.Breaking up compaction [link widoczny dla zalogowanych] is one of the keys to keeping surfaces playable, as well as a good drainage system in place. Surfaces that have become compacted will not let water through. Compacted soils have had the pore spaces squeezed out of their structure and are a complete barrier to the downward movement of water.The key to good drainage is to know the sub-soil conditions to allow for the most appropriate drainage system to be applied.Drainage ScamperWhen all the pores of the soil are filled with water, the soil is considered to be saturated. The force of gravity pulls water downward through the soil and the rate at which the soil drains at this point is called the saturated hydraulic conductivity; this rate is proportional to the square of the pore diameter. Hence coarse textured soils will drain much faster than fine textured ones.As the soil drains, the largest pores are emptied and water remains in the smaller pores. A balance, or equilibrium is reached when the force of gravity can no longer move the water against the resisting forces of adhesion and cohesion. At this point the soil is at field capacity.
Topics related articles:


[link widoczny dla zalogowanych]

[link widoczny dla zalogowanych]

[link widoczny dla zalogowanych]


Post został pochwalony 0 razy
Powrót do góry
Zobacz profil autora
Wyświetl posty z ostatnich:   
Napisz nowy temat   Odpowiedz do tematu    Forum Free Mp3 Ringtones Strona Główna -> Forum testowe Wszystkie czasy w strefie EET (Europa)
Strona 1 z 1

 
Skocz do:  
Możesz pisać nowe tematy
Możesz odpowiadać w tematach
Nie możesz zmieniać swoich postów
Nie możesz usuwać swoich postów
Nie możesz głosować w ankietach

fora.pl - załóż własne forum dyskusyjne za darmo
Powered by phpBB © 2001, 2005 phpBB Group
Regulamin