Title: Introduction Nowadays the trends of the expanding deserts become so serious that they are advancing
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3Introduction 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
4Desertification
- 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
5Cases of China as an exampleThe fai choi is
distributed in Qinghai, Xinjiang, Gansu Ningxia,
Inner Mongolia lt?????????????????????gt
6Climate
- 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.
7Factors causing Chinas desertification
(Climatic Factors)
- Low and variable rainfall
- Extreme temperatures
- High evaporation
- Strong wind
- Seasonal drought
8Factors causing Chinas desertification ( Human
Factors)
9 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.
10- 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
11- 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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13Fat 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
14Fai choi medical value Nutrients
- ??????,???????????????? ??????
- ????????,?????,????,?? ?,?????????
- ??????????????????????? ?????,????
- ?????,??????????,?????? ????
- ?????????,????????????? ????????????????????????,
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15Why 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
16 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.
17 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
18The 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.
20NOAA-16 Satellite Monitoring of the sandstorms
21- Satellite showing the intensity of the sandstorms
(horizontal visibility)
22What 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
23- 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
24What 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 . -
25The end
- Reference
- http//intermargins.ncu.edu.tw/headline/2000/westw
ard20development/dust05.htm - www.people.com.cn
- Newspaper Apple daily,Orisun,Ming Pao