
janasamkhyayude vardhanavu

oru metapopuleshanil oru thalatthil prathipravartthikkunna ore speesheesile speshyal aayi verthiricha janasamkhyayude oru koottam adangiyirikkunnu. 1969 ll richard levinukal kaarshikamekhalakalile praanikalude janasamkhyaa chalanaathmakathayude oru maathrkaye vivarikkunnathinayi mettaapoppuleshan enna padam srishtichuvenkilum eee ashayam swaabhaavikamaayo krithrimamaayo vighadicha aavaasavyavasthakalilulla jeevajaalangalkk ettavum vishaalamaayi prayogikkappettittundu. levinsinte swantham vaakkukalil paranjaal, athil "janasamkhyayude oru janasamkhya" adangiyirikkunnu.
oru mettaapoppuleshan saadhaaranayaayi niravadhi vyathyastha janasamkhyayum nilavil aalillaatha anuyojyamaaya aavaasavyavasthayum ulkkollunnathayi kanakkaakkappedunnu. classical mettaapoppuleshan sidhaanthathil, oro janasamkhyayum mattu janasamkhyayude aapekshika swaathanthryathil chakrangal nadathukayum oduvil janasamkhyaaparamaaya yaadruchikathayude (kramarahithamaya janasamkhyaaparamaaya sambhavangal kaaranam janasamkhyayude valuppathile ettakkurachilukal) anantharafalamaayi vamshanasham sambhavikkukayum cheiyunnu; janasamkhya kuravaayathinaal, prajnana vishaadathinum vamshanasha saadhyathaykkum kooduthal saadhyathayund.
vyakthigatha janasamkhyaykku parimithamaaya ayuss undengilum, mothatthilulla janasamkhya palappozhum sthirathayullathaanu, kaaranam oru janasamkhyayil ninnulla kudiyettakkaar (udaaharanathinu, janasamkhya vardhanavu anubavikkunna) mattoru janasamkhyayude vamshanaashathaal thurannukidakkunna aavaasavyavasthaye veendum kolanivalkkarikkaan saadhyathayund. avar oru cheria janasamkhyayilekku kudiyerukayum aaa janasamkhyaye vamshanaashathil ninnu rakshikkukayum cheythekkaam ("rescue ephakt" ennu vilikkunnu). janasamkhya kurayunnathu "rakshaakarthaakkalkk" avasarangal thurannirikkunnathinaal atharamoru rakshaapravarthana phalam sambhavikkam.
mettaapoppuleshan sidhaanthathinte vikasanam, uravida-sink dynamicsinte vikasanavumayi samyojichu, otappettathaayi thonnunna janasamkhya thammilulla connectivityude praadhaanyam oonnipparanju. oru prathyeka jeevivargathinte deerghakaala nilanilpp oru janasamkhyaykkum urappunalkaan kazhiyukayillengilum, pala jeevajaalangaludeyum samyuktha phalathinu ithu cheyyaan kazhinjekkum.
mettaapoppuleshan sidhaantham aadyam bhouma aavaasavyavasthakalkkaayi vikasippikkukayum pinneedu samudramekhalayil prayogikkukayum cheythu. fisheries sayansil, "upa-janasamkhya" enna padam mettaapoppuleshan sayans padamaaya "praadeshika janasamkhya" ennathinu thulyamaanu. mikka samudra udaaharanangalum nalkunnathu aavaasavyavasthayude vyathirikthamaya bhagangal ulkkollunna thaarathamyena udaaseenamaaya speesheesukalaan, praadeshika recruitmentum mattu praadeshika janasamkhyayil ninnulla recruitmentum valia metapopuleshanil undu. praadeshika janasamkhyaykku vamshanaashasaadhyathakal nissaaramayirikkanam enna mettaapoppuleshan nirvachana maanadandatthinte karsanamaaya prayogatthinethire krittsar & seyil vaadichu.
helsinghi sarvakalaashaalayile finnish jeevashaasthranjanaaya ilkka hansky mettaapoppuleshan sidhaanthathinu oru pradhana sambhavana nalki.
vettayaadalum aandolanangalum.
vettayaadalum speshyal vaividhyavum sambandhicha aadya pareekshanangal nadathiyathu jii aanu. eph. 1920kalude madhyathil roopappeduthiya lotka-voltera samavaakyathe adisthaanamaakki 1930kalil gose, ennaal kooduthal prayogam nadathiyittilla. vettakkaarum avayude irayum thammilulla bandham vettakkaaranteyum irayudeyum prarambha saandrathaye adisthaanamaakki kaalakramena janasamkhyayude aandolanathinu kaaranamaakumenn lotka-voltera samavaakyam soochippichu. eee sidhaanthathinte pravachicha aandolanangal theliyikkunnathinulla gaasinte aadyakaala pareekshanangal parajayappettu, kaaranam vettakkaaranum vettakkaaranum thammilulla edapedalukal kudiyettatthaal swaadheenikkappettirunna. ennirunnaalum, kudiyettam avatharippichukazhinjaal, janasamkhya chakrangal lotka-voltera samavaakyam pravachicha aandolanangale krithyamaayi chithreekarikkunnu, irayude samriddhiyile kodumudikal vettakkaarude saandrathayude kodumudikalude idathuvashathekku cheruthaayi maari. kudiyettatthinteyum speshyal vaividhyathinteyum gadakangal engane vettakkaaran-vettayaadal aandolanangalilekku nayikkunnuvennu parishodhichu hafekarude pareekshanangal gaasinte pareekshanangalil vipuleekarichu.
vettakkaaran-vettayaadal edapedalukalekkurichulla hafekarude pareekshanangal (1958).
vettayaadalum janasamkhyayude aandolanangalum padikkunnathinaayi, hafekar maitt speesheesukal upayogichu, onnu vettakkaaranum mattonn irayumaanu. vettakkaaranum irayum samvadikkunna praadeshikamaayi gadanaaparamaaya aavaasavyavasthayaayi ira bhakshikkunna ooranchu upayogichu addeham oru niyantritha pareekshanam aarambhichu. thudakkathil, sthirathayulla oru vettakkaaranum vettakkaaranum thammilulla edapedal srishtikkunnathil hafekark gosinu samanamaaya budhimuttukal anubhavapettu. ooranchu maathram upayogichathiloode ira enangal vegathil vamshanasham sambhavikkukayum thudarnnu vettayaadunna mrugangal vamshanasham sambhavikkukayum cheythu. ennirunnaalum, aavaasavyavasthayude speshyal ghadana parishkarikkunnathiloode, janasamkhyayude chalanathmakatha kaikaaryam cheyyaanum rund speesheesukaludeyum mothatthilulla athijeevana nirakk vardhippikkaanum thanikk kazhiyumennu addeham kandethi. irayum ooranchum (avayude bhakshanam) thammilulla dooram maattukayum vettakkaarude chalanathinu thadassangal srishtikkukayum iraye chitharikkaan edanaazhikal srishtikkukayum cheythaanu addeham ithu cheythath. eee mattangal aavaasavyavasthayude paachukal vardhippikkunnathinu kaaranamavukayum iraykku thaalkkaalika samrakshanam thedaan kooduthal pradeshangal nalkukayum cheythu. oru aavaasavyavasthayil ira praadeshikamaayi vamshanasham sambhavikkumbol, vettakkar aakramikkunnathin munbu puthiya paachukalilekku kudiyeri avaykku veendum sthaapikkaan kazhinju. paachukalude eee aavaasavyavasthayude speshyal ghadana vettakkaaranum ira enangalum thammil sahavarthithvathinu anuvadikkukayum sthirathayulla janasamkhyaa andolana maathrkaye prolsaahippikkukayum cheythu. mettaapoppuleshan enna padam ithuvare roopappeduthiyittille, speshyal hetterojenity, aavasa patchiness ennivayude paaristhithika gadakangal pinneedu speshyal aayi verthiricha speesheesukalude janasamkhyayude grouppukal parasparam engane edapedunnu ennathumaayi bandhapetta mettaapoppuleshante avasthakale vivarikkum. mettaapoppuleshanukal engane vettakkaaran-vettayaadal edapedalukale nerittu badhikkumennum janasamkhyayude chalanaathmakathaye engane swaadheenikkunnuvennum kaanikkunnathinal hafekarude pareekshanam pradhaanamaan.
levins model.
levinsinte yadhaartha maathruka anuyojyamaaya aavaasavyavasthayude niravadhi paachukalil vitharanam cheythirikkunna oru metapoppuleshanil prayogikkunnu, oru paachinullilethinekkaal paachukal thammilulla edapedal valare kuravaanu. oru paachinullile janasamkhyaa chalanathmakatha saannidhyavum abhavavum maathram pariganikkunna tharatthil lalithamaakki. addehathinte modelle oro paachum onnukil populated aano allayo.
oru nischitha samayat kaivashamulla paachukalude bhagamaayirikkatte "n". didi" enna samayat, oro adhinivesha paachinum "edidi" enna vamshanasha saadhyathayode shoonyamaakaan kazhiyum. koodaathe, 1 − "n" paachukal shoonyamaanu. oro "enn" okkulettad paachukalil ninnum propagule janareshante sthiramaaya nirakk "sii" ennu karuthuka, oru samayat "didi", oro okkulettad paachilum oru kolanivalkkarana saadhyatha "cndt" aayi maaram. athanusarichu, "dii. enn/dii. tii" enna adhinivesha paachukalude maattatthinte samaya nirakk
eee samavaakyam ganithashaasthraparamaayi logistic modalinu thulyamaanu, vahikkaanulla sheshi "k" nalkunnu
valarchaa nirakkum "aarr"
athinaal, santhulithaavasthayil, jeevivargathinte aavaasavyavasthayude chila bhagam ellaayppozhum shoonyamaayirikkum.
yaadruchikathayum mettaapoppuleshanukalum.
speshyal ghadanayeyum speeshees edapedalukaleyum kurichulla hafekarude padanangal mettaapoppuleshan dynamicsile aadyakaala pareekshanangalude udaaharanamaanu. hafekarinteyum levinukaludeyum pareekshanangal muthal, yaadruchika gadakangale samyojippikkunna modalukal srishtikkappettittundu. paaristhithika vyathiyaanavum (yaadruchikatha) thaarathamyena cheria kudiyetta nirakkum anishchithathvathino pravachanatheethamaaya sthirathaykko kaaranamaakunnuvenn eee maathrkakal theliyichittundu. ennirunnaalum, niyantritha immigration variable kaaranam hafekarude pareekshanam ananthamaaya sthiratha urappunalki.
stokkaastik paachu acupency modalukal (spoms).
levins modalinte oru pradhana poraayma athu nirnnaayakamaan ennathaanu, athesamayam adisthaana mettaapoppuleshan prakriyakal yaadruchikamaanu. aswasthamaaya aavaasavyavasthakalile speeshesukalekkurichum avayude janasamkhyayude pravarthanakshamathayekkurim charcha cheyyumbol mettaapoppuleshanukal prathyekichum upayogapradamaanu.iii.oru nischitha samaya edavelayil avaa vamshanasham sambhavikkaan ethratholam saadhyathayund. levins modalinu eee prashnam pariharikkan kazhiyilla. sthalavum yaadruchika parigananakalum ulppeduthunnathinaayi levinsinte model vipuleekarikkunathinulla oru lalithamaaya maarggam kondaakt prakriya upayogikkuka ennathaanu. eee modelle lalithamaaya parishkkaranangal paachu dynamixinaayi ulppeduthaanum kazhiyum. oru nischitha percolation threasholdil, kooduthal kadinamaaya vamshanasha thresholdukal pravachikkunna eee konfigareshanukalil aavasa vighadana phalangal sambhavikkunnu.
samrakshana jeevashaasthra aavasyangalkkaayi, mettaapoppuleshan modalukalil (eiii) mettaapoppuleshanukalude parimithamaaya swabhaavam (aavaasavyavasthaykku ethra paachukal anuyojyamaanu), (bii) vamshanaashathinteyum kolanivalkkaranatthinteyum saadhyathayulla swabhaavam enniva ulppeduthanam. eee modalukal prayogikkunnathinu, paachukalude vamshanashavum kolanivalkkaranavum asinkranas aayirikkanam ennathum shradhikkuka.
microhabithat paachukal (emhps), bacteria mettaapoppuleshanukal.
naano teknolaji prakrithidrishya paristhithiyumaayi samyojippichu, synthetic aavasa bhooprakrithikal oru chippil kettichamachathaanu, aavaasavyavasthayude naveekaranathinaayi poshakangal nalkunna naano skeyil chaanalukalulla bacteria miinii-haabittettukalude oru shekharam nirmmikkukayum vividha topological krameekaranangalil edanaazhikal vazhi bandhippikkukayum cheiyunnu, ithu samayabandhithamayi vitharanam cheytha avasarangalude paachukalude speshyal mosaik srishtikkunnu. chippile bakteeriyakalude mettaapoppuleshanukal padichukondu ithu landscape pareekshanangalkk upayogikkaam, udaaharanathinu avayude parinaama paristhithi.
jeevithacharithrathinte parinamam.
cheria varna kulangalile ubhayajeevikalude roopaantharathinte paaristhithika sthiratha polulla jeevithacharithra parinamam vishadeekarikkaan mettaapoppuleshan modalukal upayogichittundu. badal paaristhithika thanthrangal vikasichu. udaaharanathinu, chila salamanderukal roopaantharam upekshichu jala neoteinukalaayi laingikamaayi pakwata praapikkunnu. thanneerthadangalude seasonal dairkhyavum jeevivargangalude deshaadana shreniyum eathu kulangalaanu bandhippichirikkunnathum avaa oru mettaapoppuleshan undaakkunnundo ennum nirnnayikkunnu. jalakkuzhikal unangunnathinumumbulla varna kulatthinte dairkhyavumaayi thaarathamyappeduthumbol ubhayajeevikalude jeevithacharithra ghattangalude dairkhyam jalapradeshangale bhoumapradeshangalumaayi bandhippikkunna mettaapoppuleshanukalude paaristhithika vikasanathe niyanthrikkunnu.