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AsiaAt a Glance

Population: 3,721 million

Percent of World’s Population: 60.66%

Land Area: 44,579,000 sq km

Percent of Earth’s Land: 30%

Key Environmental Issues

Land use change

Desertification

Deforestation

Habitat loss

Forest loss and degradation

Water scarcity

Pollution of freshwater resources

Over population

Expansion of aquaculture andloss of mangrove areas

Degradation of coastal and marine resource

Sites for Asia

Al Isawiyh, Saudi Arabia

Aral Sea, Kazakhstan

Atatürk Dam and the Harran Plain, Turkey

Beijing, China

Dhaka, Bangladesh

Oil Well Fires, Kuwait

Huang River Delta, China

Irian Jaya, Indonesia

Isahaya Bay Reclamation, Japan

Lake Hamun, Iran/Afganistan

Mesopotamian Wetlands, Iraq/Iran

New Delhi, India

Paektu San, Korea, DPR

Phnom Penh, Cambodia

Shenzhen, China

Sundarban, Bangladesh/India

Thailand Aquaculture, Thailand

Three Gorges Dam, China

audi Arabia, although rich with oil,is lacking a more vital naturalresource: water. The kingdom has

decided to diversify its economy andmodernize its agricultural sector in orderto become more self-supporting to meetthe country’s growing demand for wheat.As Saudi Arabia has severely limited waterresources, the government decided to usethe revenues from the oil industry to adoptthe best technologies available for farmingin arid and semi-arid environments.

Center pivot irrigation has been intro-duced in Wadi as Sirhan, a large alluvium-filled graben up to 300 meters below thesurrounding plateau. Located in theextreme north along the border withJordan, Wadi as Sirhan is a remnant of anancient inland sea and is underlain by fouraquifers, two of which contain fossil watermore than 20,000 years old. The satelliteimages between 1986 and 2000 show thetransformation of the desert to agriculturethrough center pivot irrigation.

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Al Isawiyh, Saudi Arabia

Center Pivot Irrigation

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1986 (left)

This image shows Wadi as Sirhan near the villageof Al Isawiyah prior to the introduction of centerpivot irrigation.

1991 (upper right)

This image shows the region shortly after theintroduction of center pivot irrigation.

2000 (lower right)

Once established center pivot irrigation quicklyspread throughout the region.

Photo Credits:FAO—F. MattioliUSDA

Aral Sea, Kazakhstan

A Sea in Peril

T he Aral Sea, located in CentralAsia, has undergone manychanges in the recent past. The

world’s fourth largest lake before 1960, theAral Sea has been progressively drying up.The Amu Darya and Syr Darya rivers, thesea’s only inflow sources of water, nolonger reach it. Some progress has beenmade since 1990. The total water with-drawal in the basin has now stabilized atabout 110-120 cubic km/year.

The water crisis in the region contin-ues even today. The gradual drying up ofthe Aral Sea will increase environmentaldegradation with huge adverse socio-economic effects. There are a variety ofsignificant environmental problems, suchas climate change, loss of biodiversity,water pollution and air pollution, in theAral Sea Basin. The current trend isunsustainable but the poverty and exportdependencies of the Central Asian stateshave prevented real action, and the seacontinues to shrink.

The series of satellite images between1972-2001 show continual shrinkage of theAral Sea. More than 60 percent of the AralSea has already disappeared. It may com-pletely disappear in coming decades. Inthe image, black shows water, brown showsdesert areas and green shows vegetation. 1973

1987

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Photo Credits:TETHYS/JRAK—Roman Jashenko

20021999

tatürk Dam is the world’s fourthlargest dam, providing hydropowerand irrigation for Sanliurfa and the

Harran Plain of Turkey. The Atatürk Damconstruction on the Euphrates River beganin 1983 and was completed in 1990. By 1992the reservoir had filled to capacity, and isnow producing hydroelectric power andirrigation waters for Sanliurfa and theHarran Plain located southeast of the reser-voir. The Euphrates River enters the imageat the top through a gorge in the TaurusMountains and exits the image at the bot-tom. On the Euphrates, just off the imagebottom, is Lake Assad, a major Syrianreservoir. The Euphrates River is a majorinternational river whose harnessing raisesmany environmental and water resourcesissues that need to be addressed by thecountries sharing its waters. In the satelliteimages blue represents water, green repre-sents natural vegetation and brown repre-sents barren lands.

Atatürk Dam and Harran Plain, Turkey

Freshwater Resources and Dam

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1975 (left)

Before the dam and reservoir wereconstructed, most of the agriculturallands produced seasonal, low watercrops, such as barley and pistachio.This is a post harvest image, so thefields are either in fallow or wereharvested in the spring. The primaryagricultural areas are north and eastof the river. They are visible mainly asdark harvested agricultural lands. TheHarran Plain is in the southeastquadrant of the image.

1999 (right)

In 1999 the lands north and east ofthe reservoir were still dominated byseasonal agriculture. However, theHarran Plain, now provided a steadyflow of water through the Sanliurfairrigation tunnel, supports water-intensive cash crops, such as cotton,corn and soybeans. Urban and ruralpopulations have grown in size sincethe introduction of the Atatürk Damand Sanliurfa Tunnel. Official statis-tics shows that the population ofSanliurfa grew from 276,528 in 1990to 410,762 in 1997, indicating a 49%increase largely supported by eco-nomic activity due to hydroelectricpower provided by the dam.

Photo Credits:USDA/FAS

eijing, the second largest city inChina after Shanghai, is the cul-tural, political, and intellectual

center of the country, as well as a majorindustrial and commercial metropolis.Beijing’s extremely rapid industrial andcommercial development is putting pressureon the city’s historical and cultural land-marks, and causing significant loss of pro-ductive agricultural land. Like many otherlarge cities, Beijing has also encounteredserious pollution problems because of itsgrowth. The Landsat images show the city’sgrowth trends and remarkable changesduring the “reform era” since 1979.

Beijing, China

Urban Population Growth

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1978 (left)

The image shows the status of Beijingbefore the new economic reforms of1979. The light blue area in the centershows Beijing, including the ForbiddenCity. The green hills west of the city arecovered with deciduous forests. Amixture of rice, winter wheat andvegetables, represented in a range ofcolors depending upon the stage oftheir development, dominates theagricultural lands.

2000 (right)

This image shows urban growth ex-panded from the city center oftenalong major transportation corridorsand toward the airport. The estimatedpopulation was 11 million in 1992, withapproximately 7 million living withinthe city boundaries. The suburbs grewrapidly as new construction of institu-tional, industrial, and residentialbuildings covered the landscape andresulted in the conversion of primeagricultural land to urban uses. Theagricultural lands closest to the citycenter that historically been dominatedby vegetable and rice production areamong the most threatened by com-mercial and residential development.The population growth, mainly due toin-migration, increased to 13 million bythe year 2000.

Photo Credits:NOAA/NESDIS—George SaxtonNREF—Simon Tsuo

haka, the capital of Bangladesh, hasachieved phenomenal growth sincethe country gained independence in

1971. In 1971, Dhaka had a population ofalmost two and a half million. Today it has apopulation more than ten million and occu-pies over 1500 sq. km. Dhaka is one of thepoorest and most densely populated cities inthe world having 6545 people per sq. km.

Dhaka is located on an alluvial floodplainbetween the Ganges/Brahmaputra rivers andthe Meghna river. In a major flood event,about 71 of the 90 wards in the city will suffersevere damage and up to 25 percent of thecountry may be flooded. Seventy-five percentof the population of Bangladesh lives lessthan 10 meters above sea level. The monsoonrains cause repeated flooding and stormsurges from cyclones devastate populationsfar inland from the coast. The green color inthe images represent forest and agriculture,bright white spots represent planned areas forinfrastructure and gray shows urban areas.

Dhaka, Bangladesh

Uncontrolled Urban Population Growth

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1977 (left)

Dhaka is visible in the top centralportion of the image along theTurag River. Its seaport Narayanganis located 16 km to the southeastclose to the confluence with theMeghna. The confluence of theMeghna and the Ganges can be seenfurther to the southeast. These tworivers dictate life in the region.

2000 (right)

The image reveals the conversion oflow lands and agricultural areas tourban as Dhaka expands to thenorth. The very flat and broadnature of the floodplain can clearlybe seen in the shifting channels ofthe major rivers.

Photo Credits:IFAD—Anwar HossainNREL—Jim Welch

he Persian Gulf war brought aboutsome of the worst environmentalpollution ever recorded as result of

oil spills and oil fires. During the air andground war of January–February 1991, 700oil wells were damaged, of which more than600 were set on fire. Ninety-five percent ofthe oil was removed and exported. Fivepercent continues to pollute the desert witha high risk of contaminating the groundwater that is so limited in the region. Thesatellite images show the dramatic changesin Kuwait during the Gulf War. The blueshows water, green shows natural vegetation,light yellow shows desert areas and blackshows pollution from oil spills and fire.

Gulf War Oil Well Fires, Kuwait

Environmental Pollution

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1990 (left)

The August 1990 image (before the oil fire)shows the capital city of Kuwait in the upperpart of the image.

1991 (upper right)

The November 1991 image was acquiredafter the fires had been extinguished. Itshows the damage to the landscape and anumber of newly formed oil lakes.

2000 (lower right)

The January 2000 image shows that the areais developing again but the soil quality hasnot yet been restored.

Photo Credits:USACHPPM—Jack Heller

he Huang He (Yellow River) is themuddiest river on Earth and isChina’s second longest river,

running 5475 km (3,395 mi) from easternTibet to the Bohai Sea. The Huang He’syellow color is caused by a tremendousamount of mica, quartz, and feldspar in thesediment, most of which is accumulated asthe river carves its way through the highlyerodable loess plateau (wind-blown soildeposits) of north-central China, withsubstantial erosion taking place. As the rivererodes the loess, it becomes a “river of mud”(Loessial soil is called huang tu or “yellowearth” in Chinese).

Between 1979 and 2000, satellite imagesshow dramatic changes in the tip of theYellow River delta. During this period,several hundred square kilometers haveaccreted to and been eroded from the coast.

Huang He Delta, China

Environment Changes/Impacts of Land Use

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1979 (left)

Agricultural lands were few until landreclamation efforts began in the1950s. Only thirty years ago, thisplace was a vast expanse of saline-alkaline soil with limited agriculture.

2000 (right)

Between 1979 and 2000, the delta tipgrew nearly 100 square km. Aquacul-ture has expanded along much ofthe coast and agriculture overall isbetter developed.

Photo Credits:IFAD—Martine ZauggYRCC—Huanghe Feng

rian Jaya is Indonesia’s largest andmost eastern province covering thewestern half of the New Guinea the

world’s second largest island.

Indonesia is the world’s second largestproducer of palm oil, after Malaysia. Itcurrently has 3.2 million hectares offorest for oil palm plantations. Indonesiaincreased its production of palm oil bysome 6.5 million tonnes last year. Thedrive to meet demand is causing manycompanies to jump into the market andconvert forest areas into plantations.

Two major factors influencing defor-estation in eastern Irian Jaya are thegrowth of the palm oil industry and theIndonesian government’s policy oftransmigration. A third concern is oil andgas exploration.

The result of the policies for IrianJaya is a large and rapid increase inpopulation that needs employment andinfrastructure to accommodate them,while the palm oil industry finds an easysource of labor to work in newly createdplantations. Numerous negative impactsare noted on the environment and on thelocal cultures and economies.

Irian Jaya, Indonesia

Loss of Traditional Lands

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1990 (left)

The image shows tree canopy nearlyuntouched by development. Tworivers are visible, the smaller but moreimportant of which is the UvimmerahRiver to the northwest of the image.The other main river is along theborder of Papua New Guinea. Atransportation net is developing toconnect the forest resources to a smallriver port.

2000 (upper right)

The image shows a large square areain the northwest quadrant whereintervention in the forest shows itsconversion into an oil palm planta-tion. The lighter green of the monoc-ulture contrasts with the darker greenof the old growth of the rest of theforest canopy. The reddish-brownareas have been cleared for planting,but have yet to be populated by palmtrees. At the bend in the river nearthe affected forest area, a larger riverport has been established to facilitatetransportation of the palm oil.

2002 (lower right)

The intervention in the forest hasexpanded by 2002 and now reachesthe Uvimmerah River in the north-west quadrant.

Photo Credits:IFAD—German MintapradjaUNESCO—Georges Malempré

his part of Japan has a mountain-ous interior filled with coastalplains, volcanoes, and hot springs.

The Ariake Sea is a large bay almost equalin size to Tokyo Bay and Ise Bay. Duringlow tide, a vast tideland appears, whereover 15 species of valuable creatures live,such as mud skippers. The Isahaya Bay onthe Ariake Sea is one of the largest andrichest staging sites of migratory birds withan incredible amount of benthic andother organisms including mollusks andfishes. Tidal flat wetlands throughoutKorea, China and Japan are among themost threatened by the need for increasedfood production and urbanization.

The Isahaya Bay Reclamation projectseparated approximately 30 sq. km. oftidal flats from the Ariake Sea in 1997.The intent of the project was to increaseagricultural land and to decrease the riskof flooding. The land available per farmerfor vegetable production will increasethree-fold. The sea wall and its enclosedreservoir should provide a buffer toreduce the risk of flooding both from theriver and from typhoon driven high tides.

Isahaya Bay Reclamation, Japan

Tidal Flat Wetlands

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1993 (left)

This image shows the Isahaya Baysome four years before the reclama-tion project that separated approxi-mately 30 sq. km. of tidal flats fromthe Ariake Sea in 1997. Historically,the Ariake Sea has been little affectedby red tide damage, thanks to thetideland’s self-cleansing effects.

2000 (right)

On this image the seawall and thereservoir can be clearly seen. Futureagricultural areas under developmentare on the white drying tidal flats.Walls to create and protect the futureagricultural land can be seen as linearfeatures on the old tidal flats. A fewyears ago, when the sluice gatesaround the bay’s mud flats wereclosed, there were reports that therange of tide in the Ariake Sea hadshrunk. The removal of one third ofthe bay will likely have some yet-to-bedetermined effects on the aquaticecosystem, including a possibledecline in seaweed aquaculture.

Photo Credits:Courtesy of Teal Smith

istan lies in a large depression locatedbetween Afghanistan and Iran. In thecentre of this closed basin lies a

historic riverine oasis nourished by theHelmand, one of Afghanistan’s major riversrising in the western Hindu Kush. By creat-ing a distinct delta environment in a truedesert setting, the Helmand has transformedone of the region’s common salt flats into acradle of life. Remarkably, although the riverempties into an extremely arid evaporationpan, it sustains a vast and predominantlyfreshwater wetland complex, Lake Hamoun.Reaching their greatest extent with springfloods, these wetlands cover an area rangingfrom 2,000-4,000 sq. km. More than a thirdof the Iranian portion has been designatedas an internationally protected area underthe Ramsar Convention on Wetlands, but noland has been set aside for conservation inthe Afghani portion.

Reflecting a dramatic decrease in precipi-tation and drought, satellite imagery shows thesnow-covered area in the Helmand basin hasdecreased by almost two-thirds. By 2001, Iranand Afghanistan were experiencing for thethird consecutive year an extreme drought sosevere that Lake Hamoun dried out com-pletely. However, drought is not the only rea-son for Lake Hamoun’s disappearance. Sistan’senvironment has been also radically modifiedby human manipulation of water resourcessuch as irrigation schemes, which siphon flowsfrom the wetlands.

Lake Hamoun, Iran/Afghanistan

Sistan Oasis Parched By Drought

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1976 (left)

Winding through the Margo desert, theHelmand forms a dendritic delta anddissipates in a series of lagoons or“hamouns.” Numerous seasonal rivers alsoconverge in the closed basin. The imageshows dense reed beds appearing as darkgreen, while tamarisk thickets fringing themargins of the upper lakes show up as lightgreen. Bright green patches representirrigated agriculture, mainly wheat andbarley. The lakes flood to an average depthof half a meter denoted by lighter shades ofblue, while dark blue to black indicatesdeeper waters not exceeding four meters.

2001 (right)

Hamoun wetlands vanished as Central andSouth Asia were hit between 1999 and 2001by the largest persistent drought anywherein the world. The only sign of water in thisscorched landscape of extensive salt flats(white) is the Chah Nimeh reservoir in thecenter right of the image, which is now onlyused for drinking water.

Photo Credits:International Federation of Red Cross and Red Crescent Societies

he Mesopotamian marshlands areone of the world’s great wetlandscovering an estimated original

area of 15,000 - 20,000 sq. km. The marsh-lands are an important center of biodiver-sity, play a vital role in the intercontinentalmigration of birds and have long supportedunique human communities. Water reser-voirs created by large dams upstream, aswell as drainage activities in the marshlandsthemselves, have significantly reduced thequantity of water entering the marshes.Together these factors have led to thecollapse of the ecosystem.

The satellite images taken in 1973, 1990and 2000 provide a synoptic illustration ofthe great changes that have taken place inthe Mesopotamian marshlands, located atthe confluence of the Tigris and Euphratesrivers in southern Iraq and extendingpartially into Iran.

Mesopotamian Wetlands, Iraq/Iran

Disappearing Wetlands

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1973 – 1976 (left)

A mosaic of four images taken between 1973 and1976 shows the status of Mesopotamia region.Permanent lakes appear in black and seasonallakes are blue to very light blue. Dense marshvegetation (mainly Phragmites) appears as darkgreen patches, while green elongated patchesalong riverbanks are date palms.

1990 (upper right)

Permanent lakes appear in black and seasonallakes are blue to very light blue. Olive to grayishbrown patches indicate low vegetation and darkgreen patches are dense marsh vegetation.

2000 (lower right)

The image from March 2000 shows that most ofthe wetlands have disappeared. Most of the marsh-land area appears as olive to grayish-brown patchesindicating low vegetation on moist to dry ground.The very light to gray patches are bare areas withno vegetation and may actually be salt evaporatesof former lakes.

Photo Credits:UNESCO—M.L. Bonsirven-Fontana

ew Delhi has experienced massiveurban growth in recent decades,placing enormous pressure on the

institutional and natural resources thatsupport the city. The population of Delhihas increased from approximately 5 millionin 1975 to about 12.2 million in 2000, and itis projected to continue to rise to over 22million by 2021. Most of this growth is due tohigh migration rates associated with en-hanced income and employment opportuni-ties in New Delhi. The urban area has grownfrom 182 sq km in the 1970’s to more than750 sq km in 1999. This growth is primarilyat the expense of productive farmland aswell as loss of natural vegetation. At present,natural vegetation is 5.93% of the total area.The satellite images of 1977 and 1999 showthe urban sprawl in New Delhi. In the image,green represents natural vegetation and darkblue represents urban areas.

New Delhi, India

Urban Sprawl in a Megacity

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1977 (left)

The 1977 image shows the statusof New Delhi with a populationof 5.3 million.

1999 (right)

The image shows dramaticexpansion of urban areas in NewDelhi with population increasedto 12.2 million. As the popula-tion sharply rose by 46.31%during the 1990–1999 decade,more areas were converted tourban areas.

Photo Credits:NREL—Jim WelchNREL—Roger Taylor

t. Paektu is an ancestral moun-tain and the symbol of patrio-tism to the Korean people. It

embodies the spirit of the nation. Volcanicsoils and short, dry and relatively coolgrowing seasons make this high plateausuitable for agriculture. The satelliteimages document the changes in agricul-tural in this region. Here green showsnatural vegetation, blue shows water andgray-brown shows bare agricultural soilprior to emergence of crops.

Paektu San Region, Korea DPR

Agricultural Expansion in Mountain Regions

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1980 (left)

Shortly prior to the collection ofthis image the dam was constructedon the volcanic shield of PaektuSan. The newly filled reservoir canbe seen in addition to some limitedagriculture. Some of the existingagriculture appears to be related torecent burn scars.

1999 (right)

The area under cultivation on theplateau, west and north of thereservoir, is substantially greater in1999 than in 1980.

Photo Credits:USDAUSDA—Alice WelchUSDA—Bill Tarpenning

hnom Penh is the capital city ofCambodia. It is just west of the four-way river intersection, which is called

the Chattomukh (“Four Faces”). From thenorthwest and northeast, respectively, flowthe Tonle Sab and Mekong Rivers. Thesewaters merge and split into the Basak Riverand the Mekong, which flow southeast to theSouth China Sea. The Mekong River is the12th longest in the world, flowing fromwestern China to the Mekong Delta insouthern Vietnam. Phnom Penh is theMekong River’s largest city. Its populationfluctuated wildly during the 1970s and 1980s;from an estimated 1.2 million in 1971 itswelled with war refugees to 2 million ormore by 1975. By 1978 it was reduced toabout 100,000 and then rebounded to over 1million by 2000. The satellite images showPhnom Penh, the Mekong River, someirrigation works and the changes in landusein this region.

Phnom Penh, Cambodia

The City and the River

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1973 (upper left)

The areas appearing as white or gray areareas that had been under cultivation. TheMekong River on the right is clearly largerthan the tiny Tonle Sap River. This image isobviously not from the height of the rainyseason and the 2 rivers are quite distinctfrom each other. Many lakes are visible inthe image. These lakes are important tothe local population that relies heavily onfish in their diet. Phnom Penh is barelyvisible as a slightly purple area just to theleft of where the two rivers converge.

1985 (lower left)

This image does not show the yearly flood-ing either; instead the focus is on theirrigation systems set up under the KhmerRouge. The irrigation canals are evident ina white grid pattern both in the Mekongbasin and to the west of the Tonle SapRiver. The light green scattered through-out the white grid show that the ground wassomewhat newly under cultivation.

Sept. 2000 (upper right)

This image shows the region when theMekong backs up and inundates the area.The Tonle Sap Lake covers about 270 sq.km in the dry season and about 1500 sq.km. during the rainy season. In the imagethe two rivers are virtually indistinguishabledue to the flooding. Phnom Penh is justbarely noticeable at the edge of the bend inthe river.

Dec. 2000 (lower right)

Although cloudy, this image shows howmuch the waters recede in just a fewmonths. The areas in light green areprobably under early cultivation again. Theremnants of the canals built under theKhmer Rouge regime are still in evidenceto the northeast of Phnom Penh.

Photo Credits:UNESCO —Daniel Riffet

he city of Shenzhen is located justacross from Hong Kong and south-east of the Zhujian (Pearl) River

Delta Region in China. The city has been thefocus of intense urbanization, known asShenzhen Special Economic Zone (SSEZ).Comparison of these two satellite imagesshows the dramatic change in the landscapefrom 1986 to 2000, as thousands of high-risebuildings and factories have replaced previ-ous agricultural and vegetated areas. Thegray color in the image depicts urban areas,green represents natural vegetation and bluerepresents water.

Shenzhen, China

Urban Growth in an Economic Zone

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1986 (left)

The 1986 image shows a concen-trated area of development, which isprimarily limited to the lowermiddle and adjoining coastal re-gions with less than 71,000 people.

2000 (right)

This satellite image shows that by2000, the developed urban area hasexpanded to the north, northwest,and northeast and is home to morethan 1 million people.

Photo Credits:Courtesy of http://www.geocities.com/asiaglobe/

undarban, the largest mangroveforest of the world, is situated in thesouthwestern part of Bangladesh and

in the West Bengal of India, guarded by theBay of Bengal. The total area of Sundarbanis approximately 10,000 sq. km. Approxi-mately 60% of the mangrove forests fall inBangladesh and 40% in India. It was de-clared as a UNESCO’s World Network ofMan and Biosphere Reserve in 2001.Sunderban is an excellent example of the co-existence of human and terrestrial plant andanimal life. Despite high population pres-sure and environmental hazards such assiltation, cyclone flooding and sea level rise,the aerial extent of the mangrove forest hasnot changed significantly in last the 25 years.In fact, with improved management, thetiger population has increased from a mere350 in 1993 to 500-700 in 2000 and eco-tourism is progressing well. While sufficientdata is not available, several reports suggestthat forest degradation has been occurringin many parts of Sundarban. The world’smangrove forests are also becoming morevulnerable due to the significant rise ofshrimp farming in this region. The increaseof shrimp farming has negatively affectedagriculture and also contributed to the lossof mangrove forests during past two decades.The satellite images show changes in theSundarban region between 1977 and 2000.

Sundarban, Bangladesh/India

World’s Largest Mangrove Forest

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1977 (left)

The closed vegetation canopy ofSundarban can clearly be seen as verydark green in the image, representingvigorously growing vegetation.

2000 (right)

This image is a mosaic of images fromdifferent times of the year. Theagricultural lands in the west half ofthe image are pre-harvest, while theagricultural land in the east half arepost-harvest. Local areas of shrimpfarming show as light purple inpreviously dark green areas. Overalllittle change is visible. A closer look atthe Sundarbans reveals a shiftingcomposition of the wetland as waterand soil quality changes.

Photo Credits:IWM Images

uring the past three decadesaquaculture has become thefastest growing food-producing

sector and is an increasingly importantcontributor to national economic devel-opment and food security. The rapidpopulation growth in Asia is widening thegap between supply and demand for fish,thereby threatening national food secu-rity in many countries.

In the coastal area of Thailand, about54.7% (2037.65 sq. km) of mangrove wasdestroyed between 1961-1993 accordingto the Thai Royal Forestry Department.The highest rate of 129.81 sq. km./yrbetween 1979-1986 has declined since theintroduction of the intensive aquaculturesystems in 1987.

The most recent intensive culturesystem no longer requires mangroves.Since the intensive culture system wasintroduced in 1987, shrimp productionhas increased sharply, while mangrovedestruction and the total shrimp farmingarea have leveled off. Intensive culturepractices continued to improve, makingThailand the world’s leader in shrimpculture production.

At present, 85% of shrimp cultureareas employ the intensive culture system.This corresponds to a shrimp productivityof 3.13 mt/ha/yr. Even though shrimp-farming activities in the past utilized 17%of the historic mangrove area, the shrimpindustry is confident that there will be nofurther destruction from its sector.

Thailand Aquaculture, Thailand

Aquaculture in Asia-Pacific

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1973 (left)

The image of 1973 shows the coastalarea of southern Thailand withmangrove areas.

2002 (right)

The 2002 image revels a dramaticchange in land use along the south-ern coast. Much of the coastal ecosys-tem has been converted to intensiveshrimp cultivation, new infrastructureand construction of new dykes.

Photo Credits:UVic Shrimp Aquaculture Research Group

he Three Gorges Dam is located onthe Yangtze River at Saduping inHubei province in China. The

Yangtze is the longest river in Asia and thethird longest in the world, stretching nearly6,500 km across China. The Three GorgesDam will be the largest hydropower stationand dam in the world, with a 600 km long and160 metres deep reservoir. As planned, thecapacity of Three Gorges dam, 17 millionkilowatts, will top that of the largest damcurrently operating by 40 percent. The dammay end up providing as much as one-ninth ofthe nation’s electrical production: the energyof 15 nuclear power plants. In addition thedam will provide flood control for a river thathas killed one million people in the last 100years, and will allow shipping upstream toChongqing for 10,000 tonne ships.

Many issues also exist. Up to 40 percent ofthe cost of the project will need to be spent onthe vastly difficult task of relocating the over1.2 million refugees displaced by the reservoir.The reservoir will partially or completelyinundate 24,300 ha of farmland, 2 cities, 11counties, 140 towns, 326 townships, and 1351villages. In addition to commercial fish spe-cies, it will also affect endangered species,including the Yangtze dolphin, the ChineseSturgeon, the Chinese Tiger, the ChineseAlligator, the Siberian Crane, and the GiantPanda. Esthetically, the Three Gorges areknown throughout the world for their beauty.Many cultural remains will be submergedrepresenting all of many cultures, includingthe Ba, who have lived in the valley.

The physiognomy of this region is foothillsand the vegetation belongs to the evergreenand deciduous mixed forest of the sub-tropicclimate zone. The two images are composedwith a natural color composite where vegeta-tion appears natural green. The images showdramatic changes between 1987 and 2000.

Three Gorges Dam, China

Man-made Landscapes

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1987(left)

The dam site prior to the beginningof construction. The dam site is in themiddle of eastern most of the threegorges, Xiling Gorge. Portions of theXiling Gorge can be seen in the right-center and left-center of the image.

2000 (right)

Comparing the two images from 1987and 2000, the diversion and naviga-tion canals and the beginning con-struction of the 2 km concrete damcan easily be seen. An entire moun-tain was leveled to provide materialfor the dam and to make way for thenavigation canal.

Photo Credits:International Rivers Network