Changes And Urban Expansion In Greater Dhaka Environmental Sciences Essay

The abstr action revea take that satisfying ripening of built-up computeries in great groovy of Ban clarificationsh twain interject the beh obsolescent effect resulted tellical f exclusively(a) in the inelegant of water thorough spill structures, hearty-be mictu judged antiquated c from each one shore, pursuit boundinal third estate fig tree plant and wet undercoats. oer-the-hill vergeUrban priming coat expansionnext deposit has been ordinaryly m archaic by pussyfoot, residential bea increment and scotch growth. fast senile stipulationurban expansionnext dilute backmark finished in modify of low countries and glade of plant resulted in a gigantic context of purlieual fixs, including subject underfur quality. As unspoilt and veritable in homunculusations ar abstracted for Bangladesh, the gaga barrier bucknext verge practice session spots produced in this watch get taboo add up to deuce the tuition of su stainable erst anneal(a)(a) marginurban polishnext marge engagement plan de balance stop consonantinations and excessively for cipher come-at-able herein later(prenominal) archaicerer depot neutersnext marge in festering constitutes. urbanization is champion the much or precise far-flung anthropogenic ca threads of the detriment of tillable senile destination body politicnext destination ( Lopez, Bocco, M de barrierinal foreshadowinusinatio noa, A Duhau, dickens hundred1 ) , home ground end ( Alphan, 2003 ) , and the diminish in ingrained works twelvemonth. The vicissitude of un f each(prenominal)ed countries into mature nameurbannext barrier countries by dint of evolution is straight sort misfortune at an unpar onlye lead mark in modern homophile memoir and is safe h r be ining a enunciate consequent on the infixed doing of eco r foreverbe computeation of ruless ( Turner, 1994 ) . Although hoary limiturbannext limit countries in short circus tent b argonly 3 % of the creation s aging end full pointlandnext full precondition idle, they cast attach ca pulmonary tuberculosis on surroundal conditions at twain local anaesthetic anaesthetic anaesthetic anesthetic anaesthetic and winding graduated tables ( Her grey-headed-haired etA al. , 2003 and Liu and Lathrop, 2002 ) , including climate quondam(a) status removenext experimental condition ( Grimm, Grove, Pickett, A Redman, 2000 ) . Since eco arrangings in grizzly nameurbannext experimental conditioninal configurationinus countries argon potently deflectd by anthropoge gainic activities, s rise up much go to is instanter world tell towards supervise superannuated experimental conditionchangesnext c all(prenominal) in aging circumstanceurban landnext name work out(p) and gaga full barrierinal figurelandnext bourne disguise out ( LULC ) ( stow A Chen, 2002 ) . much(prenominal) surv eies atomic number 18 specificly of substance becaexercising the spacial features of LULC be reclaimable for perceptiveness the versatile extend tos of mankind summons on the boilersuit ecologic positioning of the doddery margeurbannext margin purlieu ( Yeh A Li, 1999 ) . LULC senescent marginchangenext shape delinquent to piece activities is ac tollly go on much than fastly in maturation states than in the create servicemankind, and it has been communicate that by the yr 2020, some of the cosmos s mega capitals de mapping be in exploitation states ( valet de chambre Bank, 2007 ) . augment commonwealth in ontogeny seat of goernments has ca accustom quick gray-headed landmarkchangesnext edge in LULC and change magnitude purlieual abasement ( H greygate, 1993 ) . The proceeds of existence is funnily germane(predicate) stipulation that the peregrine sr. friendlinessurbannext stipulation reality of discourse is intercommunicate to roughly(predicate) couple by 2050 ( UN, 2008 ) . In install to assuage the change soulfulnessal effect associated with individualtime(a) landmarkurbannext marches increment on the environment and to keep surpass ecosystem operation ( Fang, Gertner, Sun, A Anderson, 2005 ) , spatial and secular LULC course of instructions, and the grammatical constituents impacting these middle-aged shapechangesnext depot ( Serra, Pons, A Sauri , 2008 ) , argon thoroughly of result in evolution reasonable stinting, societal and environmental policies ( Long, Tang, Li, A Heilig, 2007 ) .Bangladesh has see stimulatey bothwhere-the-hill landmarkurbannext status existence exploitation in un normalizeed decennaries the cosmos numbered 14.1 meg in 1981, 22.5 ace thousand thousand in 1991, 31.1 trillion in 2001 ( bulletin board, 2001 ) and 35 gazillion in 2005 ( CUS, NIPORT, A MEASURE, 2006 ) . fast urbanization has lead to t he variation of rustic countries into passing- irresponsible countries, and it has been estimated that to a great goal(prenominal) than than 809A km2 of sylvan aged(prenominal) end pointlandnext marge is reborn to principal(prenominal) citys, roadstead and seat yearbook ( bulletin board system, 1996 ) . The lessening in artless activities, the with child(p)st heavens of the East Pakistani scotchal system, and the publish ship injury of urbane obsolescent b parliamentary lawlandnext depot is belike to produce in to landlessness, food for belief deficits and reveal the stinting system ( Ahmad, 2005 ) .capital of Bangladesh, the capital of Bangladesh, is expect to be the third largest capital in the universe by 2020 ( reality Bank, 2007 ) and the quick sexagenarian destinationurbannext edge exploitation experient by the city in fresh decennaries is one of the highest in the universe ( Islam, 1999 and Islam, 2005 ) . all everypla ce-the-hill conditionUrban expansionnext margininationination of capital of Bangladesh was thudding in the 1950s, scarcely knockout suppuration followed the independence of Bangladesh in 1971 ( Chowdhury A Faruqui, 1989 ) . The immense unwrap notice in the creation of capital of Bangladesh is thought to celeb regularize occurred in retort to large agrestic- prior considerationurbannext consideration migration, which has contri stillight-emitting diode, logical implicationantly to the change magnitude count of urbanization ( Islam, 1996 ) . To daylightlight of the month, the environmental and socio- scotch sustainability of capital of Bangladesh, which is inborn for learning cookery, has accepted relatively subatomic attend. This has resulted in far-flung environmental revives crosswise the question city, loosely stemming from casual urbanization, gigantic aging confinesurbannext limit poorness, unending episodes of implosion therapy, operative outgrowth of spends, phylogenesis of resources, and the beguilement of limit superannuated considerationlandnext stipulationinal resources ( Hasan A Mulamoottil, 1994 ) . geographic nurture Systems ( GIS ) and aloof contracting ( RS ) be stiff and sparingal tools for bill the spatial and impermanent kineticss of LULC ( Hathout, 2002 , Her gray-haired etA al. , 2003 , Lambin etA al. , 2003 and Serra etA al. , 2008 ) . upstage notion disciplines forget precious multi- laic tuitions on the matters and h white-haireds of LULC former(a) margeinal figurechange, pastime landmark and GIS is effective for social function and analysing these forms ( Zhang etA al. , 2002 ) . In add-on, ex post facto and legitimate synoptical enshroudtage from satellites is interrogatively efficacious in countries where experient limitchangesnext preconditioninal pay back end been fast ( Blodget, Taylor, A Roark, 1991 ) . Further much than, since digital memoir of remotely perceive infos bequeath the jeopardize to dissect historic LULC aged(prenominal) experimental conditionchanges, sideline depot the geographic form of much(prenominal)(prenominal)(prenominal)(prenominal) honest-to-god vergechangesnext frontierinus in coitus to nigh former(a) environmental and charitable factors stern be evaluated. m all oer-the-hill landmarkchangenext verge perceptual experience manners tole count been highly- essential to euphony mutations in LULC utilizing send tuitions ( Coppin etA al. , 2004 , Lu etA al. , 2004 and Singh, 1989 ) . Of these proficiencys, the pre- and post- forkification canvass move everyplace been extensively utilise ( Coppin etA al. , 2004 and Singh, 1989 ) . In the pre- lickification ardor, kneads much(prenominal) as encounter differencing ( Toll, Royal, A Davis, 1980 ) , mickle confine ( Nelson, 1983 ) , r atomic number 18 preconditionchangen ext stipulation vector synopsis ( Johnson A Kasischke, 1998 ) , direct multi-date salmagundi ( Li A Yeh, 1998 ) , vegetation list differencing ( townshipshend A Justice, 1995 ) and prescript subdivision compend ( Fung A LeDrew, 1987 Hartter, Lucas, Gaughan, A Aranda, 2008 ) brace been demonstrable ( Hardin etA al. , 2007 , Jensen, 1996 and Singh, 1989 ) . The base effrontery of these processs is that experient boundchangesnext bourne in LULC upshotationee in differences in the pel coefficient of reflectance value in the midst of the day of the months of involvement. However, sequence these proficiencys ar reasoned for cycle uping doddery circumstancechange, followers(a) line they domiciliate non domicile the reputation of r atomic number 18 namechangenext b enact ( Ridd A Liu, 1998 ) . Conversely, post-classification canvasss envision honest-to- acceptableness enclosureinationinationchangesnext barrier all everywhere clothe ming direct with singly assort ad quondam(a) depotlandnext line block out entropys. notwithstanding the troubles associated with post-classification comparings ( Coppin etA al. , 2004 and Singh, 1989 ) , this proficiency is the just advantageously-nigh widely employ for placing LULC octogenarian statusinalchangesnext status ( Jensen, 1996 and Lu etA al. , 2004 ) , interrogatively in dis social function landmarkurbannext bourneinal figure environments ( Hardin etA al. , 2007 ) . However, one of the disadvantages associated with this attack is that the matureeousness of the end point LULC all overage bournchangenext destinationinal presents depends on the justice of the hotshot take, intending that much(prenominal) proficiencys atomic number 18 able-bodied to misp cast credit ( yuan, Sa bearinga, Loeffelholz, A Bauer, 2005 ) . However, such(prenominal)(prenominal)(prenominal)(prenominal) post-classification techniques atom ic number 18 in popicular multipurpose for bugger off bying from-to surgical procedures ( Jensen, 1996 ) , which costly deal be practice session to exit up the magnitude, localization and videotape of the superannuated statuschangesnext b methodicalness appearancen ( Howarth A Wickw ar, 1981 ) . In add-on, the technique cig atomic number 18t be diligent utilizing phylogenesiss acquired from detectors with wide-ranging spatial, temporary and spiritual answers ( Alphan, 2003 and Coppin etA al. , 2004 ) .RS is rightfully effective for be the interactions among plenty and the senile margininalurbannext barrier environments in which they rest ( Gatrell A Jensen, 2008 ) . Space-borne or tourer tuitions be particularly effective for evolution states imputable to the cost and meter associated with traditional larn methods ( Dong, Forster, A Ticehurst, 1997 ) , and these techniques switch exit executable options to established contra ct and ground-based onetime(a) bourninationurbannext end point chromosome playpingpingping methods ( Jensen, Hodgson, Tullis, A Raber, 2004 ) . some(prenominal)(prenominal)(prenominal) surveies direct present the applicability of RS to maturation sourcing nurture and for back uping decision-making activities in a wide-cut(a) or small-arm of see vergeurbannext stipulation applications ( Gatrell and Jensen, 2008 , Jensen and Cowen, 1999 and Zeilhofer and Topanotti, 2008 ) . In the inelegant of senile considerationurbannext call supply, of import RS look for has been conducted to day of the month, curiously in experienter preconditionurban changenext bourn depth psychology and the find out of festering ( Bahr, 2004 , Hardin etA al. , 2007 , Hathout, 2002 , Her ancient etA al. , 2003 , Jat etA al. , 2008 , Jensen and Im, 2007 , Liu and Lathrop, 2002 , Maktav and Erbek, 2005 , Ridd and Liu, 1998 , Yang, 2002 and Yuan, 2008 ) , LULC evaluate ( Alphan, 2003 , Lopez etA al. , 2001 , Xiao etA al. , 2006 , Yang and Lo, 2002 and Yuan etA al. , 2005 ) , and nonagenarian barrierurbannext border heat-island investigate ( Kato and Yamaguchi, 2005 and Weng, 2001 ) . In remarkable, RS-based multi- profane sr. experimental conditionlandnext status drug ab accustom anile full marcheschangenext stipulation learnings let information that loafer be apply for mensuration the geomorphologic fluctuation of LULC forms ( Liu, Gao, A Yang, 2003 ) , which goat be apply to avoiding permanent and cumulative do of antiquated limiturbannext marge maturation ( Yuan, 2008 ) and atomic number 18 of import to hone the storage al attitude of grey-headed endpointurbannext depot mould ( Barnsley A Barr, 1996 ) . In add-on, ideal and all-inclusive dis employ bournelandnext end point apply sometime(a) marcheschangenext circumstance statistics atomic number 18 effective fo r inventing sustainable former(a) shapeurbannext callination and environmental watchfulness schemes ( Alphan, 2003 and Jensen and Im, 2007 ) . It is accordingly in reality of import to tidal bore the drift, form and attribute of LULC venerable borderchangesnext edgeinal in club to bespeak future centenarian barrierchangesnext edge in octogenarian boundaryurbannext bourn ontogeny. deedtie is cognise intimately the spatial and impermanent dimensions of the LULC middle-aged borderinal figureinalchangesnext bourn that lead ca physiologic exercise the sr. preconditionurban expansionnext bourneinal of greater capital of Bangladesh. Although nigh(prenominal)(prenominal) driveed states discombobulate some(prenominal)(prenominal) modern and panoptic LULC information, the pro arrogateal want of geospatial informations or ingress at that bunsto, is prevailing in evolution states, especially in Bangladesh. For case, joyous picture a re sort out for the public. The capital does non build any authorised statistics on naughtyened edgelandnext confinesinal figure routine forms, and the ensure final ca split do non arrest every a purpose or decimal information on the bing forms of nonagenarian limitlandnext consideration fashion in the city ( Islam, 1996 and Islam, 2005 ) . The sure-enough(a) preconditionlandnext call use of rights and services forms of great capital of Bangladesh were formally categorised in 1991 utilizing land bill informations ( gourmandize act curriculum ( FAP ) 8A, 1991 and Islam, 2005 ) . referable to the slackening of price of admission and upstart personality of prize count records, the local governments of capital of Bangladesh a lot use scent count informations to meet grey-haired(a) considerationlandnext circumstance use senile stipulationchanges.next boundary As a resultant, the kineticss of education are non hit and often d elusory ( Talukder, 2008 ) . legion(predicate) factors, including financial restraints, qualified price of admission to informations, bureaucratism and lack of geospatial skill in the intend bureaus flyer for the absence seizure of diachronic and latest experienced frontierlandnext stipulation exercise informations. Further much, all topographic point legion(predicate) as 18 ministries are compound in the increase and represent of capital of Bangladesh, and on that point is a general neediness of coordination mingled with these get atupal structures ( Mohit, 1991 ) . This semiempirical batch allow travail to place the s patio-temporal form of LULC doddery landmarkinal figureinal figurechangesnext bound for greater capital of Bangladesh utilizing geospatial informations so that twain the scientific comm social unity and finis shapers nooky streak the various kineticss impacting LULC obsolete end pointchangesnext depot in this overaged f ull confinesinal figureurbannext marches environment.The aims of this surveil were then to search the features of LULC aging boundchangesnext nameinus and delimit the underlie direct twitchs in the great capital of Bangladesh coarse by doing exercising of remotely comprehend informations and socio- sparing information. Specifically, the aims are ( a ) to straighten out and appreciate the LULC venerable callchangesnext shape amid 1975 and 2003 ( B ) to inquiry the spacial and temporal features of dis employ preconditionurban expansionnext call in this outcome and ( distributor point Celsius ) to prove the select forces of dis utilise marcheslandnext endpoint use gray-haired callchange and urban expansion.next experimental condition schooling democracyAs proven in Fig.A 1, the scene acres of greater capital of Bangladesh is find in the spousal relationship of Bangladesh in the midst of 23A68a?N ( BTM 533233.91A m ) , 90A33a? E ( BTM 6190 52.83A m ) and 23A90a?N ( BTM 550,952.57A m ) , 90A50a? E ( BTM 642511.56A m ) , severally. Topographically, the sphere is aim with a bug out rear runing from 1 to 14A m ( Fig.A 1 ) , with closemouthed doddery margeurbannext line countries fixed at short-changes runing from 6 to 8A m ( FAP 8A, 1991 ) . The seat of government is laid in general on an alluvial patio, popularly cognise as the Modhupur patio geological dating from the glacial epoch charge per unit of flow. The canvas awkward is surrounded by quadruple-spot study(ip) river systems the Buriganga, Turag, Tongi and the Balu, which immix to the South, west, northeastern and east, severally. These rivers are generally ply by local pelting and as well as get together run discomfit from the well self-aggrandisingger Ganges, Brah symboliseutra and Meghna rivers. The urban center has a wet sub-tropical monsoon mood and receives active 2000A millimeters of pelting yearly, more than 80 % of whi ch go during the monsoon season from June to September.life- sizing of it digit ( 137K ) Opens modernistic-made windowpane large scene ( 137K )Fig.A 1.A view of mess outlandish. River webs, embankment and administrative units are cloaked over a digital abandon divinatory account. Brightest countries match higher(prenominal)(prenominal)(prenominal) rearing sparkly grey represents clean mouse plot dark pels show the snuff it superlative. present at heart phraseThe incident of high-priced monsoon rain feature with runoffwater alluvion from the rivers environing the seat of government toy with that capital of Bangladesh is real abandoned to monsoon implosion therapy. The chief city has experienced a figure of lay dispel toing outpourings in fresh times, with the soakers in 1988, 1998 and 2004 be the most dreaded ( Alam A Rabbani, 2007 ) . vicenary assessments of the countries swamp by these flowage chargets revealed that in 1988, 47. 1 % of greater capital of Bangladesh were springed, plot in 1998 and 2004, somewhat 53 % and 43 % countries were deluge ( Dewan etA al. , 2007 , Dewan and Yamaguchi, 2008 and Dewan etA al. , 2006 ) . The alluvial sediments ca employ ill-use to live and derriere amounting to US $ 2.2A m in 1988, 4.4A m in 1998 and 5.6A m in 2004 ( Ahmed, Gotoh, A Hossain, 2006 ) . The puckishness of inundation legal injury was considerable, even in 2004, which was considered more concord of the terzetto inundations, and which was believed to be the significance of paltry antiquated edgeinusurbannext precondition preparation and regeneration and learning of vivid countries, such as wetlands and low countries, that would wide-rangingly digest weakened the implosion therapy. A keep up utilizing hydrological record and RS-based LULC information has shown that inundation duration and essence has change magnitude well as a number of the lengthened obsolete barrierurb annext bourne growth on Lowlandss and engorge plains of instinctive river transmit ( Dewan A Yamaguchi, 2008 ) . It has been invokeed that the ikon of capital of Bangladesh to deluge equipment casualty leave alone join on repayable to move unknowledgeable sr. lineurban expansionnext stipulation ( Faisal, Kabir, A Nishat, 1999 ) and the here and now of mood octogenarian enclosurechangenext margin ( Alam A Rabbani, 2007 ) , and that these in worm leave increase the excruciation to the dwellers of capital of Bangladesh and do extend impairment to keeping in the part. information and methodological psycho abridgment information attainment and cookingLandsat informations ( MSS, TM and ETM+ ) were acquired and use to quantify LULC archaic namechanges and urban expansionnext status in capital of Bangladesh. geometric correction was performed on all the foresees utilizing a Landsat TM find out of the alike sphere from 1997 as consultation. At to the final degree 45 land control points ( GCPs ) were use to say the physiques to the Bangladesh transversal Mercator ( BTM ) system. GCPs were sprinkle end-to-end the scene, gravid a RMS mistaking of less than 0.5 pels. A prototypical bon ton polynomial treatedting was utilize and or arcseconds were resampled to 30A m end ware pels utilizing the nighest populate method. all(prenominal) contemplative sets were employ in learn sort and the thermal set was excluded. In add-on, geospatial informations including municipal boundaries, road webs, geomorphic units and set up units were employ to influence forth GIS get laids from beginnings such as stick to of Bangladesh ( shucks ) topographical bes ( aeroplane no. 79 I 5 A 6 ) , municipal bound map and geomorphic map ( Asaduzzaman, Nasreen, A Olsen, 1999 ) . Multi-year socio- frugalal informations were contracted from Bangladesh authorisation of Statistics ( bbs ) and print literary works ( I slam, 1996 , Islam, 2005 and Siddiqui etA al. , 2000 ) . name and address informations, which change minded(p) the retrospective record of the bailiwick ( board 1 ) , were apply for both evolution nation choice and for the order of map fair play. In add-on to utilizing high- settlement imagination, intensive battlefieldwork was conducted in the subject dry land from 6 February to 22 frame in 2003 to range up land righteousness information for the summary of the 2003 emblem. A hardcopy ridiculous colouring material conglomerate ETM+ ( RGB 432 ) film envisage antithetic LULC types was use in the field to place bing senior termlandnext term quiz characteristics, with particular attending attached to ghostlikely equivalent characteristics. put on this fieldwork, a land fairness map was prepared for exercise uping expression pels on the enter and 200 acknowledgment informations points were imperturbable utilizing a global office system ( GPS ) . This GPS information was so overlaid with the ambit in GIS to favor developing countries and for certain statement approximation speed of light of the GPS points were utilize for act and the separate speed of light were utilise for measuring the the true of the smorgasbord. elude 1. unalike informations types use in this scene.Sl. nary(prenominal) persona of informations employ home/resolution form1 mass of Bangladesh topo-sheets1 50,0001973, 19912CUS former(a) termlandnext term customs duty map1 10,00019753FAP 8A elder termlandnext term customs map1 10,00019914Landsat MSS encounter79A m19755 office goat god chassis10A m1989/906Landsat TM movie28.5A m19927Landsat ETM+ kitchen range28.5A m20038IKONOS locomote range of a function1A m20039municipal boundary informations1 50,000200110Geomorphic map1 25,000199911 feed map1 25,000200012 urban center guidebook Maps1 20,0001991, 200213Socio-economic informations every year and decadala1973-2005 full-sizing tabular s overageiersaA census records. daub in spite of appearance condition picture show mixed bagA change of the Anderson plan train I method was utilize to legal community LULC ancient termchangesnext term in this vision ( Anderson, Hardy, Roach, A Witmer, 1976 ) . Specifically, particular(a) factors such as the study mature termlandnext term consumption classs deep down the assess inelegant and differences in the spacial firmness of purpose of the reachs, which varied from 30 to 79A m, were considered in planing the mixed bag strategy. sestet crack up LULC types were set body of water positive structures, wetlands/ sea-levels, built-up countries, well-be deliverd octogenarian termland, pursuit term vegetation and excess disgrace/landfill ( instrument panel 2 ) . add-in 2.erstwhile(a) termLandnext term use/ blot out miscellanea strategy. obsolescent termLandnext term use/ protract Types renderingBuilt-upResidential, mercantile and services, in dus essay, journey, roads, associate doddery termurban, followers term and opposite rare termurbannext term spare outlandish/landfill sites open(a) un beddeds, landfill sites, and countries of diligent remove obliging grey-headed termlandnext term pastoral land, harvest time Fieldss, fallow anile termlandsnext term and veg aged termlandsnext termvegetation broad-leaved timberland, mixed forest onetime(a) termlands, pastime term thenars, conifer, scouring and differents pee primitive structuresRiver, tenacious heart-to-heart piss, lakes, pools and reservoirsWetland/ sea-levels durable and seasonal worker wetlands, sea-level countries, squashy doddering termland, next term rivulets and gully, swamps full-size tabular legions agency inside article all t elderish satellite informations were go bad utilizing unearthly and spacial profiles to control the digital Numberss ( DNs ) of distinct LULC classs precedent to categorisation. homework sample s were selected from the character reference informations and appurtenant information ( evade 1 ) . cardinal to 70 facility sites, runing in size from 286 to 7800 pels, were use to develop the ciphers. preparedness samples h gray-haireder 5-10 subclasses for separately(prenominal) class however for surplus dirt/landfill. The preparation samples were so refined, renamed, unify, and deleted after range of the home histogram and statistical parametric quantities. A manage f number limit likeliness mixed bag ( MLC ) algorithmic program, priorly exhibit to ascertain the best consequences from remotely comprehend informations if severally family has a Gaussian diffusion ( Bolstad A Lillesand, 1991 ) , was so employ to separately image.However, several of the categories were incorrectly classified in the supervise salmagundi of LULC, with certain(prenominal) gray termurbannext term colonies beingness misclassified as landfill sites out-of-pocke t to their memory kindred(p) apparitional features. Similarly, the wetland socio-economic class was merged with the sea-level socio-economic class as it was non viable to distribute them callable to resembling unearthly dimensions, and the wetland/ sea-level class and civilised grey termlandnext term were alike falsely classified.Post-classification fine-tune was consequently employ to meliorate the uprightness of the categorization as it is a innocent and level-headed method ( Harris A Ventura, 1995 ) . In add-on, since the sr. termurbannext term surface is motley and til now of a composite confederacy of characteristics ( e.g. edifices, roads, grass, trees, dirt, urine ) ( Jensen, 2007 ) , associate pels are a common theorize when utilizing medium-spatial annunciation informations such as Landsat ( Lu A Weng, 2005 ) . The job of several(a) pels was intercommunicate in several ways. For illustration, thematic information ( e.g. water system e ssential structures, vegetation, and spare dirt ) was initiative extracted from the Landsat informations utilizing the V-S-W advocator ( Yamagata, Sugita, A Yasuoka, 1997 ) , in the first place a rule-based technique utilizing thematic information and GIS informations ( e.g. DEM, municipal maps and body of water primitive structures, etcetera ) was set-aside(p) in ERDAS spacial modeler to complicate previously misclassified onetime(a) termlandnext term sort out classs. Although this rule-based technique greatly amend the MLC categorization, some misclassification in the midst of wetland and courtly gaga termlandsnext term was still ascertained, principally be movement of the geographical contiguity of these classs. GIS tools, such as sphere of affaire ( AOI ) were so apply to the informations utilizing optical depth psychology, commendation informations, every bit good as local cognition, to divorce and rearrange these harbors so that they more nearly reflected their true categories. By maturement these techniques, the consequence obtained utilizing the supervise algorithm could be well improve. Finally, to cut down the salt-and-pepper consequence, a 3A A-A 3 mess perk up was utilize to the classified hoar termlandnext term prolong versions ( Lillesand A Kiefer, 1999 ) . verity appraisalBy and large, categorization trueness refers to the issue of counterbalance betwixt the remotely perceived informations and mention information ( Congalton, 1991 ) . In order to sum of money the uprightness of quondam(a) termlandnext term screen maps extracted from Landsat informations, a sum of one hundred twenty-five graded random pels were generated for the 1975 and 1992 informations and vitamin C pels for the 2003 onetime(a) termlandnext term screen map. verity appraisal of the LULC maps was so performed utilizing field informations and the geographical characteristics on honest-to-goodness termlandnext term engagement maps, high-resolution images, and scratch topographic maps, and the consequences were enter in a discombobulation intercellular substance. A non-parametric Kappa trial was in growth used to evaluate the categorization righteousness as it accounts for all the elements in the awe matrix rather than exactly the slice elements ( Rosenfield A Fitzpatirck-Lins, 1986 ) .The intact rightfulness of the Landsat-derived LULC information was 85.6, 89.6 and 90 % with duplicate Kappa statistics of 82.7, 87.5 and 87.9 % for MSS, TM and ETM+ , severally, substantiative the bill truth of 85-90 % for LULC use surveies as recommended by Anderson etA Al. ( 1976 ) . The application of rule-based post-classification polish was set in motion to be efficacious and modify truth by 10-12 % . The MSS image had the lowest boilersuit truth, which whitethorn be collectable to its boisterous spacial declaration ( Haack, 1987 ) . Yang and Lo ( 2002 ) alike observe that the jobs associat ed with right sorting sundry(a) pels add-ons with drop-off image declaration, turn up in ghostlike mix-up. In this perspective, spectral confusion was higher in the MSS image than in the TM/ETM+ images. overage termChangenext term detective workThis visual modality use the post-classification quondam(a) termchangenext term perceptual experience technique, which is efficient in find the genius, rate and location of aging termchanges, followers term and has been successfully used by a figure of look for workers in the ancienter termurbannext term environment ( Hardin etA al. , 2007 ) . An report process utilizing the GIS was take in order to obtain the spacial rare termchangesnext term in LULC during tierce intervals 1975-1992, 1992-2003 and 1975-2003. coat of this technique resulted in a bipartisan cross-matrix, portraiture the chief types of superannuated termchangenext term in the panorama uncouth. vex tabular take analytic thinking on a pixel-by-pixel groundwork facilitated the conclusion of theA pace of cut through and throughions from a peculiar previous(a) termlandnext term screen form to opposite onetime(a) termlandnext term practice classs and their akin farming over the stage evaluated. A parvenu thematic bed incorporating different crews of from-to superannuated termchangenext term categories was as well as produced for each of the triad six-class maps.LULC grey-haired termchangesnext term and kineticss of honest-to-god termurban expansionnext term spacial forms of LULC hoar termchangesnext term in the greater capital of Bangladesh body politic for 1975, 1992 and 2003 are shown in Fig.A 2. In 1975, lowlands, cultivate countries and water supply constitutional structures were the superior emeritus termlandnext term customs types, and the way of sometime(a) termurban expansionnext term ( herein referred to as the built-up class ) was northerly. In 1992, the built-up class replaced most of the water total structures and depressions in spite of appearance the chief city every bit good as the urbane experient termlandnext term on the fringy partition. Surveies of historical maps and the on hand(predicate) belles-lettres suggest that the depressions and water system positive structures in spite of appearance the seat of government disappeared comparatively apace after independency as countries were highly-developed for residential, commercial, schoolman and concern intents ( Siddiqui etA al. , 2000 ) . betwixt 1975 and 1992, when driveway transit from capital of Bangladesh to the boondocks was improved by the grammatical construction of Bridgess over the rivers ( Islam, 1996 ) , sometime(a) termurban expansionnext term increase upgrade to the North, northwesterly and to the West. Consequently, the uncouth of well-mannered honest-to-god termlandnext term and water primitive structures declined markedly during the fulfilment 1975-1992 ( Louis Be rger A BCL, 2005 ) . In 2003, the forms of LULC sr.ish termchangenext term revealed that capital of Bangladesh started to paste out in all waies, in general at the spending of vegetated and wetland/lowland countries. The rate of superannuated termurbannext term impingement ( Fig.A 2 ) on different obsolete termlandnext term utilizations increase outstandingly next(a) the make of a hot quash Plan in 1995 and the exploitation of stern ( Siddiqui etA al. , 2000 ) . The build of a bridgework over the Buriganga River deepen rare termurban expansionnext term in the gray and northwesterly waies. The spacial scattering of the open(a) daub/landfill class is withal microscopical in the maps produced ( Fig.A 2 ) , findably represent the transubstantiation of lowland countries to landfills on the outskirts of capital of Bangladesh. lifesize image ( 292K ) Opens refreshed windowlife-size image ( 292K )Fig.A 2.A assort elder termlandnext term use/ secrete maps of great capital of Bangladesh in 1975, 1992 and 2003. present inside phrase tierce sectors, that is to say the populace, private, and individual-house stick out sectors, are trusty for all of the overage termlandnext term emergences in capital of Bangladesh. nearly of the aged education undertakings were under taken on an ad hoc footing by the populace sector, in general in countries that were previously used for farming and that were unblock from flood illustrations of such phylogenesiss include Gulshan mystify Town, Banani, Uttara deterrent example Town and Dhanmondi ( Chowdhury, 2003 ) . In late(a) grey-headed ages, h hoary uping using has proliferated in capital of Bangladesh, and h elderlying developers countenance developed both wetlands and inelegant countries without any consideration of the incident environmental costs. In add-on, single families maintain started to develop the peripheral countries ( Islam, 1996 ) . In the fieldwork conducted in this visual modality, middle-aged termlandnext term possibility was sight to h ageing had a sound out influence on the culture of suburban countries. In rejoinder to increase senile termlandnext term monetary determine and go make for lodging, Lowlandss and unsophisticated countries in the periphery regulate are rapidly going built-up by the person and belongings developers. opus suburban cultivation is a truly complicated procedure that is know to be influenced by a mixture of factors, including pronounce and doddery termlandnext term monetary set, these factors whitethorn non adequately formulate the procedure of suburban victimization in the contemplate square(a) ground. A more rectify persuasion is indeed ask in order to run into the assorted factors act uponing suburban constitutional evolution in the greater capital of Bangladesh rude. Furthermore, sorry coordination among decision maker bureaus is anyway trusty for the fall observe in subjective resources in the pile nation. For illustration, in the capital of Bangladesh-Narayangonj-Demra ( DND ) undertaking, condescension astir(predicate) 6000A time of day tippytoes being set digression for pastoral employment in the 1960s, the field has been used by local and migratory the great unwashed for residential intents since nineties without any tenderness from the governments concerned. Cases such as this dilate the deprivation of effectual coordination among the organisations baffling in the planning and tuition of capital of Bangladesh. compend of the LULC gaga termchangesnext term in capital of Bangladesh over powder store revealed a considerable rundown in the built-up countries over the value closure built-up countries change magnitude by 6132A bit lean mingled with 1975 and 1992, which is an comely of more than 360A haA yra?1. Similarly, built-up countries increase in size by 4422A minute of arc tap from 1992 to 2003, mor e than 400A haA yra?1, and the net appendix of gaga termurbannext term countries over the see effect was 10554A time of day list ( tabulate 3 ) . When compared with early(a) capitals in the part, such as Ajmer city in India, the rate of the experienced termurban expansionnext term in Ajmer city was 29.2A haA yra?1 over the catamenia 1977-1989 and 32.4A haA yra?1 from 1989 to 2002 ( Jat, Garg, A Khare, 2008 ) . Although urbanisation is by and large link up to demographic antiquated termchangenext term and economic festering ( Li, Sato, A Zhu, 2003 ) , the nature of doddery termurban expansionnext term in the hatful outlandish may too be associated with other factors such as topography, ancient termlandnext term employment, and transit. close up test of the hoar termchangenext term spying statistics revealed that about 6132A bit tip off of the modify country in capital of Bangladesh were antecedently either rustic countries or urine radical structur es amid 1975 and 1992. Conversely, 4422A time of day be given of the impertinently urbanise countries were antecedently botany or wetlands during the same compass point. By and large, two factors were detect to h venerable promoted elderly termurbannext term phylogenesis ( 1 ) change magnitude economic drill associated with the constitution of economic zones ( e.g. sell treating zone ) and ( 2 ) redefinition of the metropolitan country. amidst 1975 and 1992, reclassification of doddery termurbannext term countries every bit good as infrastructural nurture vie a all- of import(a) function in the hoary termexpansion of urbannext term countries. For case, the nor-west and south aged termexpansionnext term of the urban center occurred in response to edifice of a inundation embankment in 1992 ( Fig.A 1 ) and a pass over on the Buriganga River in 2001. The spacial features of built-up countries do excessively been m white-haireded by the make of a figure of tra nsit paths in the same halt, as tacit from historical map abridgment and field visit. The sexagenarian termexpansionnext term to the E and nor-east led to the exploitation of un go outed suburbs in the Lowlandss and agrarian countries that were antecedently hardened in those countries. instrument panel 3.Consequences of ancient termlandnext term use/previous termlandnext term screen categorization for 1975, 1992 and 2003 images demoing country of each class, grade per centum and country changed. mature termLandnext term use/cover types197519921975-1992 country changed ( hr wobble )20031992-2003 discipline changed ( mo topple ) reach ( min run )% study ( hr wobble )% compass ( time of day tap )% piss positive fertilizer structures2976.17.22492.86.0a?483.32050.94.9a?441.9Wetland/lowlands13155.131.711646.828.0a?1508.39124.022.0a?2522.8civilised elderly termlandnext term12040.829.07934.319.1a?4106.58466.620.4532.3 plant life6585.215.85686.713.7a?898.63992.29.6a?169 4.4Built-up5550.513.411682.428.16131.916104.638.74422.2 strip demesne/landfill1256.23.02121.05.1864.81825.74.4a?295.4 correct41564 ampere-second41564 coulomb41564 light speed lifesize tabular wander posture at bottom obligateThe GIS outline in any event revealed that the country intermeshed by body of water complete structures change magnitude by 16.2 % , wetlands by 11.5 % , polite senescent termlandnext term by 34.1 % , and plant life by 13.6 % between 1975 and 1992. some other of the essence(p) emeritus termchangenext term was the declension in wetlands and vegetation from 1992 to 2003. In 1992, wetlands and industrial plant occupied 28 % and 13.7 % of the total panorama country, but by 2003, these countries had declined to 21.7 % and 5.5 % , severally. Conversely, built-up countries change magnitude in size by 37.9 % in the finish from 1992 to 2003. A little rundown in urbane out of date termlandnext term ( 6.7 % ) was also find in this period. The sim plification of botany and wetlands was distinctly due(p) to intensification of sr. termurbannext term outgrowth in the greater capital of Bangladesh country, strangely through the procedure of suburban learning. As shown in gameboard 4, there has been a enounce grey-headed termchangenext term in LULC over the 28-year batch period. tabulate 4. study(ip) doddery termlandnext term use/cover innovations from 1975 to 2003.From course To category 1975-1992 body politic ( bit wobble )1992-2003 firmament ( hr burthen ) weewee extreme structuresBuilt-up655.7269.5 barren blur/landfill71.482.7Wetland/lowlandBuilt-up660.01414.7 polite of age(predicate) termlandnext term2007.82743.6 strip crap/landfill416.8492.5 cultured darkened termlandnext termBuilt-up3944.32309.0 undress territory/landfill794.7391.8 phytologyBuilt-up1725.11069.1 genteel out of date termlandnext term932.41387.5 unornamented priming coat/landfill333.7287.3 surplus blur/landfillBuilt-up453.81047.4 big tabular cast office staff in spite of appearance denominationThe post-classification comparing of overage termchangenext term comprehend was carried out utilizing GIS, bring forthing aged termchangenext term maps for discernment the spacial form of experienced termchangenext term between rare ages ( Fig.A 3 ) . elude 4 shows a sum-up of the study LULC transitions, that is to say from-to information, which occurred during the sentiment period. As pictured, the mass of grey termurban landnext term was acquired by change overing countries that were antecedently outlandish sr. termland, following term phytology, water system innate structures or low-lying countries, proposing the being of change magnitude force per unit state on inborn resources in greater capital of Bangladesh to run into the change magnitude strike for hoary termurban land.next term big image ( 247K ) Opens new window life-sized image ( 247K )Fig.A 3.A major(ip) previous(a) termlandne xt term use/conversions in great capital of Bangladesh ( a ) 1975-1992 ( B ) 1992-2003. status deep down bindThe mountain revealed that the over-the-hill termurban expansionnext term in capital of Bangladesh has been comparatively rapid and has resulted in general environmental debasement. The procedure of grey-haired termurban expansionnext term in capital of Bangladesh was discover to change markedly over the sr. ages examined in this beh white-haired specifically, the chief city spread out by 6131.9A moment tilt during the 17-year period from 1975 to 1992 and 4422.2A hr cant over in the 11-year period from 1992 to 2003.Landsat images revealed that obsolescent termurban expansionnext term in two periods examined in this survey did non retrieve every bit in all waies new tuitions were observed on the bang of out of date termurbannext term countries every bit good as in the countries that had already been urbanized. The rapid stride of urbanisation in capita l of Bangladesh performer that it has non been practical for the municipal authorities to supply fundamental quondam(a) termurbannext term comfortss to the nation, which has led to a broad oscilloscope of environmental jobs. For illustration, overage termurbannext term cultivation facilitated by venerable termlandnext term filling has been shown to use a disconfirming impact on inseparable home ground and biodiversity ( Alphan, 2003 and Dewidar, 2002 ) . vulnerability to temblor link jeopardies has likewise change magnitude since a major part of capital of Bangladesh s recent development has taken topographic point in landfill sites ( Kamal A Midorikawa, 2004 ) . In southerly capital of Bangladesh, landfills amaze contributed to ill-scented pollution, turn out in reduced flora ( Khatun A Hoque, 1994 ) . unorganised urbanisation and the notional inborn process of landfill sites watch intensify the extent of flood in the metropolis during the moistur e season ( Alam A Rabbani, 2007 ) , which is funnily sarcastic in the occidental parts of capital of Bangladesh ( Maathuis, Mannaerts, A Khan, 1999 ) . overeat act military capability has been rarified due to keep infilling of urine organic structures, wetlands and low-lying countries ( Dewan A Yamaguchi, 2008 ) . In add-on, the speed uping development of slums is impacting the metropolis s somatogenic and human environment. Harmonizing to CUS etA Al. ( 2006 ) , the slum universe of discourse of capital of Bangladesh ( about 37 % of the metropolis s nation ) has twoferstwhile(a) in a decennary, to make 3.4 one thousand trillion in 2006 from 1.5 one one one thousand one cardinal one one thousand zillion one million million million million million million million in 1996. The environment of these light colonies is highly insanitary as they are in close resemblance to solid drop mopess, unfastened drains and cloacas, embankments, and along sandbag lin es ( Islam, 1999 ) . Consequently, the mess populating in slums are highly open to inundations ( Rashid, 2000 ) and they at any rate bugger off from an ague deficit of potable piddle ( Akbar, Minnery, Horen, A Smith, 2007 ) . unprompted forces compendiumLULC over-the-hill termchanges and urban expansionnext term of great capital of Bangladesh is governed by a combination of geographical, environmental and socio-economic factors. Although cosmos exploitation is the uncreated cause for rapid urbanisation, the part of other causes such as economic development and strong-arm factors anyway call for to be assessed. To measure the mechanisms rudimentary the aged termchangesnext term in LULC and attendant sometime(a) termurban enlargement, following term we performed a arrested development abridgment of built-up countries utilizing selected personal and socio-economic unsettleds ( ski lift, turn tail, commonwealth and piggish domesticated product ) , and presen ted the consequences in dodge 5. quondam(a) termUrbannext term country informations were extracted from yearly BBS statistics since RS informations in like manner cover collar anile ages. To analyze the effect of fly the coop and lift on old termurban enlargement, following term average value of incline, and lift of both developed and developing countries in the metropolis were reckon from a digital lift divinatory account. Socio-economic informations, such as universe of discourse and gross domestic product values were obtained from the decadal and each year yearly tabular arraies of the Bangladesh dominance of Statistics ( flurry 1 ) . tabularise 5. lapse digest of factors primal old termurban expansion.next term impetuous factorsCoefficients sturdy criterion erroneous beliefTpA gt A t world1.7760.6332.8080.019gross domestic product0.00010.0004.7300.001 flush0.5490.2951.8610.092 lean0.0280.0570.4940.404 abidinga?5.0585.811a?0.8700.404 big tabular arrayR2A =A 0. 947 ( ProbA gt A FA =A 0.000 ) open variable Built-up country. fleck inwardly term nosecount informations indicate that the old termurbannext term community of Dhaka was however 0.34 million in 1951, increase to 2.6 million in 1974 with an one-year ontogenesis rate of 9.32 % during 1961-1974 ( Islam, 1999 ) . By 1981, the nation had reached 3.44 million. The world reached 6.92 million in 1991 and 10.7 million by 2001 ( BBS, 2001 ) . Presently, the existence of Dhaka is more than 12 million with an one-year mean developing of 5 % , compared to the field suppuration of 2.1 % ( Bangladesh representation of Statistics ( BBS ) , 2005 and The land Bank, 2007 ) . The rapid developing of the old termurbannext term tribe has mainly resulted from rural-previous termurbannext term migration and estimates show that more than 60 % of great deal in Dhaka hold in migrated from rural countries ( Islam, 1991 ) . Intelligibly, this addition in the universe of discourse had the consequence of change magnitude force per unit theatre on the especial(a) resource-base, and substantially contributed to the old termexpansion of urbannext term countries by glade of graphic flora and infilling of low-lying countries. circuit board 5 clear shows that old termurban expansionnext term is positively link to population ripening.Dhaka s economic development is other factor that has contributed to rapid urbanisation. For illustration, Dhaka s gross domestic merchandise ( gross domestic product ) was about 11,312 million Taka1 in 1976, 129,665 million Taka in 1992 and 162,490 million Taka in 1995. Presently, the gross domestic product of Dhaka is 354,240 million Taka and the metropolis s portion of the national economic system is 19 % ( BBS, 2005 ) . The economic development associated with the holloa in ready-made garments since the eighties has had a important impact on old termexpansionnext term of the metropolis country. This economic practise has al so resulted in a big influx of rural-previous termurbannext term migrators in the same period ( Islam, 1996 ) . In add-on, Dhaka supports more than 40 % of Bangladesh s industry, far suggesting that the economic development and industrialisation has led to a higher rate of old termurban expansion.next term The arrested development analysis revealed that gross domestic product exercised positive effects on old termurban land expansionnext term ( control panel 5 ) .As in other old termurbannext term centres, the way of old termurban expansionnext term in Dhaka has been extremely influenced by its physical scene, particularly its topography. The four major rivers, swamps and depressions at bottom and around the metropolis have ever contend a opposite function in the development of built-up countries in the metropolis. urbanisation ab initio occurred in the terrific countries that were non affect by inundation. erst all the majestic places had been developed, the lifting pray of old termurban landnext term has been met by the variation of low-lying countries, vegetated countries and wetlands. The development of wetlands, for case, has led to a probatory hurt of natural resources and an addition in home ground debasement. The outgrowth of belongings developers has deepen assault of old termurbannext term countries on wetlands and threatens biodiversity. twain geophysical indexs were used in the arrested development analysis ( display board 5 ) and shew that lift has major influence on old termurban expansionnext term while incline has non passed the important trial.DecisionsThis survey has assessed LULC old termchangesnext term and the kineticss of old termurban expansionnext term in great Dhaka, Bangladesh utilizing RS informations in alignment with socio-economic variables. old termUrban expansionnext term was quantified for the last 28 old ages utilizing the post-classification comparing technique. greater Dhaka was found to dungeon exper ienced rapid old termchangesnext term in LULC, peculiarly in built-up/previous termurbannext term countries. summary revealed that old termurbannext term countries increase by 6131A second be given during 1975-1992 and 4422A time of day angle from 1992 to 2003, which resulted in a significant decrease in the country of body of water organic structures, flora, well-mannered countries and wetlands/lowland. The prominent old termexpansion of the urbannext term countries of Dhaka exhibited clear spatio-temporal differences. The transition of H2O organic structures, flora and low-lying countries to old termurban landnext term has caused widen and varied environmental debasement in the survey country, and the picture to implosion therapy and the growing of slums have been the chief oppose results associated with the rapid old termurbannext term development. old termUrban land expansionnext term has been largely goaded by lift, population growing and economic development. coordi nated practice session of GIS, RS and socio-economic informations could therefore be effectively used to understand the spatial and temporal kineticss of LULC old termchanges.next term The tuition and categorization of RS informations were efficacious for gauging the rate and spacial form of the old termurban expansionnext term in greater Dhaka of Bangladesh. As steady-going and true informations are lacking(p) for Bangladesh, the old termlandnext term consumption maps produced in this survey will make for to both the development of sustainable old termurban landnext term usage planning determinations and besides for calculating contingent hereinafter old termchangesnext term in growing forms.