Passage 2

題材：科技類

題目：Water treatment 2: Reed Bed

題型：判斷題 3+填圖題3+補全段落選擇5+多選題2

文章大意：

Water Treatment 2: Reed Bed

ANowadays subsurface flow wetlands are a common alternative in Europe for thetreatment of wastewater in rural areas. Mainly in the last 10 to 12 years therehas been a significant growth in the number and sizeof the systems in use. Compared to common treatment facilities, wetlands arelower in cost investment, lesser to maintain, and are ideal for denselypopulated rural or suburban areas rather than urban areas.

B TheCommon Reed has the ability to transfer oxygen from its leaves, down throughits stem and rhizomes, and out via its root system. As a result of this action,a very high population of micro-organisms occurs in the root system, with zonesof aerobic, anoxic, and anaerobic conditions. Therefore with the waste watermoving very slowly and carefully through the mass of Reed roots, this liquidcan be successfully treated.

C A straightforward definition of a reed bed is if you have dirtywater in your pool or water, which is heavily polluted, Reed Beds will beplanted to make the water clean again. This is good for ecology and livingorganisms and fish in the water. Reed Beds have a wide range of qualities andarc acceptable for cleaning everything from secondary to tertiary treatment ofmild domestic effluent, to rural waste and even heavy industrial contaminants.The reason why they're so effective is often because within the bed's rootsector, natural biological, physical and chemical processes interact with oneanother to degrade or remove a good range of pollutants. Reed beds can be builtin a number of variants, but mainly they are of the horizontal flow or vertical(down) flow configuration where water flows through the beds horizontally orvertically.

D Horizontal-flow wetlands may be of two types: free-watersurface-flow (FWF) or sub-surface water-flow (SSF). In the former the effluentflows freely above the sand/gravel bed in which the reeds etc. are planted; inthe latter effluent passes through the sand/gravel bed. In FWF-type wetlands,effluent is treated by plant stems, leaves and rhizomes. Such FWF wetlands aredensely planted and typically have water-depths of less than 0.4m. However,dense planting can limit oxygen diffusion into the water. These systems workparticularly well for low strength effluents or effluents that have undergonesome form of pretreatment and play an invaluable role in tertiary treatment andthe polishing of effluents. The horizontal reed flow system uses a long reedbed, where the liquid slowly flows horizontally through. The length of the reedbed is about 100 meters. The downside of<4hc horizontal reed beds is thatthey use up lots of land space and they do take quite a long time to produceclean water.

VERTICAL FLOW REED BED SYSTEMS

E Avertical flow reed bed is a sealed, gravel filled trench with reeds growing init (see the picture below). The common reed oxygenates the water, which helpsto create the right environment for colonies of bacteria to break down unwantedorganic matter and pollutants. The reeds also make the bed attractive towildlife.

How avertical flow reed bed works?

F Invertical flow (downflow) reed beds, the wastewater is applied on top of thereed bed, flows down through a rhizome zone with sludge as substrate, then theroot zone with sand as substrate and followed by a layer of gravel fordrainage, and is collected in an under drainage system of large stones. Theeffluent flows onto the surface of the bed and percolates slowly through thedifferent layers into an outlet pipe, which leads to a horizontal flow bed andis cleaned by millions of bacteria, algae, fungi, and microorganisms thatdigest the waste, including sewage. There is no standing water so there shouldbe no unpleasant smells.

GVertical flow reed bed systems are much more effective than horizontal flowreed-beds not only in reducing biochemical oxygen demanded (BOD) and suspendedsolids (SS) levels but also in reducing ammonia levels and eliminating smells.Usually considerably smaller than horizontal flow beds, but they are capable ofhandling much stronger effluents which contain heavily polluted matters andhave a longer lifetime value. A vertical Reed bed system works more efficientlythan a horizontal reed bed system, but it requires more management, and itsreed beds are often operated for a few days then rested, so several beds and adistribution system arc needed.

H There are several advantages of Reed Bed Systems overtraditional forms of water treatment: first, they have low construction andrunning costs; second, they are easy management; third, they have an excellentreduction of biochemical oxygen demand and suspended solids; last, they have apotential for efficient removal of a wide range of pollutants.

I Reed beds are natural habitats found in floodplains, waterloggeddepressions and estuaries. The natural bed systems are a biologically proved,an environmentally friendly and visually unobtrusive way of treatingwastewater, and have the extra virtue of frequently been better than mechanicalwastewater treatment systems. In the medium to long term reed bed systems are,in most cases, more cost effective in installment than any other wastewatertreatment. They arc robust and require little maintenance. They are naturallyenvironmentally sound protecting groundwater, dams, crocks, rivers andestuaries.

Questions 14-16 TRUE/FULSE/NOT GIVEN

14 The Reed bed system is a conventionalmethod for water treatment in urban area.

15 In the reed roots, there’s a series ofprocess that help breakdown the pollutants.

16 Escherichia coli is the most difficultbacteria to be dismissed

Question 17-19 (No more than three words)

部分答案：

判斷題

14.FALSE

15.TRUE

16. NOT GIVEN

填圖題

17.Sludge

18.sand

19.gravel

補全段落選擇題

20.A

21.B

22.E

23.C

24.G

25.B

26.D

多選題

參考閱讀：

C9T3P2 Tidal Power

Passage 3

題材： 商業類

題目：廣告

題型：選擇5+Summary 4+判斷5

文章大意：

1.介紹時間從事公告

2. 4種階段作出廣告

3.在這個人之前，文字敘述language description，image picture

4. 列舉Case redmeat，

5. 自己的理念，basicconcepts，creativity，customs response

6. 盡管他的理念任然，但有些東西過時

參考閱讀：

C6T3P2 MotivatingEmployees under Adverse Conditions

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（責任編輯：zyc）

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