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Introduction Nowadays the trends of the expanding deserts become so serious that they are advancing

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Title: Introduction Nowadays the trends of the expanding deserts become so serious that they are advancing


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Introduction Nowadays the trends of the
expanding deserts become so serious that they are
advancing towards non-deserts area.They have
increase their desert margin and bring a lot of
unfavorable effects to us both locally and
globally
4
Desertification
  • It refers to the extension of words
    desert by man s direct and indirect action is
    known as desertification.It takes place at the
    margin of arid region i.e marginal land

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Cases of China as an exampleThe fai choi is
distributed in Qinghai, Xinjiang, Gansu Ningxia,
Inner Mongolia lt?????????????????????gt 
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Climate
  • These four regions have an annual rainfall of
    about 50-680mm.They have great variable of
    rainfall as they are situated in the continental
    .As a result they have continental climate of
    extreme climate of diurnal range of temperatures
    .They also have frost free days range from 60
    days to 160 days.

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Factors causing Chinas desertification
(Climatic Factors)
  • Low and variable rainfall
  • Extreme temperatures
  • High evaporation
  • Strong wind
  • Seasonal drought

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Factors causing Chinas desertification ( Human
Factors)
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Background
  • China is one of the world most serious countries
    which posses large areas of wildly distributed
    desert
  • Occupied the whole countries 27.3
  • Every year there are the rate of desertification
    is 2640 m2 desertification.
  • The deserts are distributed in Northeast, North
    West regions.
  • . The affected people amounted to about 4 Billion
    people
  • 2 Billion of farm affected by the sandstorms
  • The food production become seriously unstable.

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  • caused 1 billion of pasture being servely damaged
    causing the pasture farm become degradation
  • dams, river channels and the water service
    departments had also caused buried or damaged by
    the sandstorms.
  • every year desertification had caused loses
    approximately 540 Billion dollars
  • Semi-Arid and arid areas with large carrying
    capacity of people are another main reason
    causing the desertification

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  • In 1997 United Nations stated that, the arid and
    semi arid areass population density should not
    exceed more than 7-20 people.
  • But in China, many places population density has
    exceed more than 60 and above
  • As a result, leading to the over-cultivation,
    over-grazing, over gathering of wild plants for
    example having medical uses, lumbering,
    inappropriate use of water supply
  • Caused vast amount of land being turned into arid
    areas some wild plants like???????? that are
    easily extracted are attracted by some farmers as
    the price of them are very high and profitable.

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(No Transcript)
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Fat choi( ?? )-1 What kind of vegetation does
this belongs to? 2 The roles in protecting the
soil
  • Ø     A kind of Algae Ø     Simple
    structureØ     Drought-resisting plant with
    hairy surfaces to reduce the rate of
    transpiration.Long and extensive root system
    enables it to obtain the ground water.It needs
    little water or dew to survive.
  • Ø    Act as a role in binding the soil
    particles together

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Fai choi medical value Nutrients
  • ??????,???????????????? ??????
  • ????????,?????,????,?? ?,?????????
  • ??????????????????????? ?????,????
  • ?????,??????????,?????? ????
  • ?????????,????????????? ????????????????????????,
    ???????????,????????????????

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Why do they like to gather the Fat Choi1 Lucky
name?2fat Choi rich in nutrients ?
  • People like to buy it because it sounds like a
    lucky word .They think that when you eat it .It
    will make you become wealthy .(??)Ø      But
    actually the nutrients of Fat choi is the same
    as the other vegetation
  • Selling fai choi will be profitable

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The Market of fai choi
  • The sales of fai choi usually would be delivered
    to Guangtong South-east Asia s Chinese
    people(80)
  • Every year the sales revenue amounted to ten
    millions above.
  • Until 2000-6-13 the government set the law
    prohibit the gathering and transaction of it
  • However there is still a black market selling the
    fai choi at a high price.

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The problems led to over-gathering of the fat
choi  
  • Ø     Accelerates the rate desertificationØ   
    Only ? ? of it can cause damage 10 heters of land
    (approximately equal to 16 football courts )
    Ø    Soil degradation emergence of desert like
    landscape and cause the decline of the
    productivity of the land.Ø    ?surface runoff
    as it is being removed ,the precipitationgt
    infiltration capacity of the soil.Ø    Soil
    erosion and flash flood resulted Ø    Create
    dust storms

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The harmful effects of desertification in China
Global
  • Ø     Sandstorm will blow to the U.S.A SE
    AsiaØ     Air pollution affects the air
    qualityØ     Cause respiratory illness-lung
    diseaseØ    Transport disturbance Air, land,
    SeaCauses silting of the channel like Huang He
    ,river Chiang Jiang

?????????
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Sandstorms that blow to other countries are
caused by cyclonic movements.
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NOAA-16 Satellite Monitoring of the sandstorms
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  • Satellite showing the intensity of the sandstorms
    (horizontal visibility)

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What are the measures and solutions to solve this
problems?
  • Ø     Wind beaksØ     Afforestation is done to
    reduce wind erosion stabilize the soil
    structureØ     Government policies-prohibit the
    transaction of it Ø     Citizens are educated
    for the causes remedies to desertificationØ   
    Alternative employment opportunities are
    developed to reduce the pressure on land Ø   
    Reforming the structure of production-develop the
    high economic value and environmentally friendly
    strains of plants

Climate Balloon
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  • Ø    Making the full use the desert resources
    like light, heat and wind to develop solar energy
    and wind energyØ    Change the wild plants (?? )
    that are having medical value to artificial
    planting
  • Provide early warnings of the sandstorms attack
    using satellite, radar to predict occurrence

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What is the effectiveness in carrying out these
methods?
  • In solving of the problems of desertification, a
    government policy is the most effective one.
    Because it is a planned economy and posses many
    resources and money, also have the power to carry
    out promptly..
  • Recently China using an methods of returning the
    farms to the state ( ???? ) and receive some
    food from the government. The land will be used
    to planting the windbreaks. It is found that it
    is very efficient .

 
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The end
  • Reference
  • http//intermargins.ncu.edu.tw/headline/2000/westw
    ard20development/dust05.htm
  • www.people.com.cn
  • Newspaper Apple daily,Orisun,Ming Pao
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