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Paleoecology of carboniferous arboreous Lycopsids from order Lepidodendrales with special consideration of region of Balkan peninsula

dc.contributor.advisorStevanović, Vladimir
dc.contributor.otherStevanović, Branka
dc.contributor.otherSudar, Milan
dc.contributor.otherKolar-Jurkovšek, Tea
dc.creatorĐorđević-Milutinović, Desa Đ.
dc.date.accessioned2016-01-05T11:46:14Z
dc.date.available2016-01-05T11:46:14Z
dc.date.issued2012-10-02
dc.identifier.urihttp://eteze.bg.ac.rs/application/showtheses?thesesId=62
dc.identifier.urihttps://fedorabg.bg.ac.rs/fedora/get/o:3372/bdef:Content/download
dc.identifier.urihttp://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=41904911
dc.identifier.urihttp://nardus.mpn.gov.rs/123456789/2055
dc.descriptionTokom perioda karbona, od pre 320 do pre 306 mliona godina, u području tropskog pojasa (paleoekvatora) Evroameričkog kopna, razvijale su se močvarne šume čiji su edifikatori bile drvolike prečice reda Lepidodendrales. Prečice generalno pripadaju razdelu Lycopodiophyta i predstavljaju jednu od najstarijih grupa biljaka, čija evolutivna linija traje sve do današnjih dana. Njihovi najstariji predstavnici Asteroxylon, .Drepanophycus i Baragwanathia pojavili su se pre oko 400 miliona godina i spadaju u grupu prvih kopnenih biljaka. Pored toga Lycopodiophyta su evolitivno bile i prve biljke koje su formirale fanerofitnu životnu formu (rodovi Cyclostigma i Archaeosigillaria u gornjem devonu pre 370 miliona godina). Tokom karbona, drvolike prečice su dostigle svoj maksimalan razvoj. U to vreme veliki prostori paleotropskog pojasa bili su prekriveni močvarnim šumama u kojima su dominirale Lycopodiophyta čija su stabla prevazilazila 40 metara visine. Najveći broj karbonskih prečica pripadao je redu Lepidodendrales i rodovima Lepidodendron, Synchysidendron, Diaphorodendron, Lepidophloios i Sigillaria. Krajem karbona, pre oko 300 miliona godina sve drvolike prečice su izumrle, i koliko je za sada poznato, u okviru ovog razdela više se nisu pojavljivale drvolike životne forme. Danas predstavnici Lycopodiophyta predstavljaju marginalnu grupu biljaka, minorne uloge i značaja u okviru različitih vegetacija, čiji predstavnici (Lycopodium, Selaginella, Isoetes i dr.) nemaju gotovo nikakvih morfoloških sličnosti sa predstavnicima iz reda Lepidodendrales. Najveći deo uporedne analize izmedju Lepidodendrales i recentne denroflore bio je baziran prvenstveno na principima aktuelizma i zakonitostima koje se javljaju prilikom fosilizacije biljaka. Aktuelističke metode su primenjene zato što je utvrdjeno da postoje bazične sličnosti u razvoju vegetacija gornjeg karbona i neogena/kvartara. Tu prvenstveno treba pomenuti pojedine uticaje/dogadjaje koji su doveli do formiranja i diferenciranja različitih vegetacijskih pojaseva, kao što su pojava Karbonskog i Pleistocenskog ledenog doba, nastanak intenzivnih orogeneza (Hercinsko/Varscinska i Alpijska), formiranje sličnih močvarnih staništa, postojanje tropskog vegetacijskog pojasa, kao i činjenica da su karbonske kao i neogene močvarne šume ostavile za sobom izrazito velike količine uglja. Paleotropske šume u kojima su dominirale drvolike prečice reda Lepidodendrales predstavljaju izuzetno značajnu i na osnovu fosila veoma dobro dokumentovanu šumsku vegetaciju čiji se kompleksni ekološki značaj može sagledati u sledećem: 1. Neobnovljivi energetski resursi sadržani u ogromnim količinama karbonskog uglja koji je nastao uglavnom od stabala Lepidodendrales. 2. Konvergentne morfo-anatomske karakteristike sa filogenetski udaljenim kopnenim (vaskularnih) semenim biljakama (drvoliki habitus, tipovi grananja, strukture slične semenima, pojava monokarpije). To ukazuje da su se mnoge krakteristike biljaka, kao i životne forme (u ovom slučaju fanerofitna) pojavljivale nezavisno i više puta u filogenetski udaljenim evolutivnim linijama. 3. Tek sa formiranjem i razvojem bujnih paleotropskih šuma došlo je, zahvaljujući povoljnoj šumskoj mikroklimi, pogodnim staništima i gotovo neograničenom izvoru hrane, do ubrzanog razvoja kopnenih životinja. U cilju objašnjenja razvoja i dinamike ovih šuma analizirane su paleoekološke osobine pojedinih rodova koji su bili njihovi edifikatori. Kao referentni rodovi uzeti su oni za koje postoji najviše fosilnih i literaturnih podataka i koji su već ranije utvrdjeni kao morfotipovi, kao što su Lepidodendron, Synchysidendron, Diaphorodendron, Lepidophloios i Sigillaria. Ovi rodovi su svojim morfoanatomskim karakteristikama, prvenstveno opštim izgledom habitusa, tipom grananja, visinom stabala i odlikama korenskog sistema uporedjivani sa strukturnim karakterisitkama recetnih predstavnika dendroflore, pre svega sa drvećem i drvenastim semenim biljkama. Na osnovu pojave i uloge sličnih ili različitih morfo-anatomskih karakteristka kod ispitivanih fosilnih Lepidodendrales i referentnih predstavnika recentne dendroflore utvrdjene su brojne konvergetne strukturne karakteristike koje objašnjavaju paleoekološki karakter i značaj izumrlih Lepidodendrales. Prilikom analize opšteg izgleda habitusa i visine stabala utvrdjeno je da su monokarpne vrste, posebno rod Lepidodendron, mogle da budu visoke i preko 40 m (koliko je za sada utvrdjena najveća visina ovog roda), što ukauje da su neki predstavnici Lepidodendrales visinom približavali recentnim četinarima, odnosno da su bili viši od mnogih današnjih drvenastih cvetnica. Konstatovane su analogne heteroblastične i monokarpne odlike vegetativnih i reproduktivnih adultnih stadijuma predstavnika drevnih rodova Lepidodendron, Synchysidendron i Lepidophloios i recentnih monokarpnih vrsta iz familija Agavaceae, Bromelidaceae i Asteraceae. Monokarpni Lepidodendrales pokazuju određenu sličnost sa nekim džinovskim rozetastim (zeljastim) monokarpnim vrstama roda Agave koje upadljivo, heteroblastično, menjaju izgled habitusa tokom reproduktivnog stadijuma. Pored toga, monokarni predstavnici Lepidodendrales se opstajanjem na staništu i posle reproduktivne faze mogu porediti sa drvenastim monokarpnim vrstama roda Tachigali kod kojih nema heteroblastičnih promena, ali koje se, takođe zadržavaju na staništu još izvesno vreme posle reproduktivne faze, obezbedjujući svojim stablom prostor mladim jedinkama iste vrste. Uočena je i sličnost heteroblastičnih promena tokom smenjivanja vegetativnog u reproduktivni stadijum kod Lepidodendrales i prelaza iz juvenilnog u adultni stadijum recentnih polikarpnih vrsta roda Pseudopanax. Uporedne analize bazirane na gradji i ulozi listova i lisnih jastučića dovele su do zaključka da su listovi Lepidodendrales, koji periodično opadaju ostavljajući za sobom lisne baze (lisne jastučiće), jedinstvena karakteristika reda Lepidodendrales i da se ne mogu definitivno porediti sa recentnim biljkama. Nasuprot tome, postoje izvesne analogne morfološke odlike osnovnih delova lista, pre svega lisne ploče i ligule Lepidodendrales i nekih recentnih biljaka. Na poprečnom preseku lisna ploča Lepidodendrales slična je lisnoj ploči nekih vrsta roda Pinus iz grupe Diploxylon, odnosno vrstama iz grupe Haploxylon. Donekle se i ligula Lepidodendrales može porediti sa ligulom kod familije Poaceae, pre svega u pogledu sličnog položaja - u pazuhu lista, tj na prelazu lisne sare u lisnu ploču. Rizomorfni ili korenski sitem Lepidodendrales označen kao stigmarija (rod Stigmaria) može se uporediti sa korenovima nekih drvenastih recentnih biljaka sa vlažnih i močvarnih staništa. Naime, može se pretpostaviti da su bočni korenski izdanci stigmarija imali aeracionu ulogu slično pneumatoforama na korenovima današnjih vrsta iz rodova Taxodium, Nyssa, ili mangrova vegetacija (Rhizophora spp.). Na osnovu velikog broja fosilnih ostataka zaključeno je da su stigmarije bile površinski organi ili površinski deo korenskog sistema čiji se podzemni deo, poput drugih podzemnih biljnih organa, nije sačuvao u fosilnom obliku. U doktorskoj disertaciji je obavljena i uporedna analiza paleotropskih šuma Lepidodendrales i odgovarajućih recentnih šumskih zajednica. Utvrdjeno je da paleotropske šume najviše sličnosti pokazuju sa suptropskim močvarnim šumama u kojima dominira močvarni četinar Taxodium spp. Obe ove, vremenski veoma udaljene, zajednice odlikuje slično močvarno stanište, kao i sličan nasumičan raspored i opšti izgled edifirkatorskih vrsta, najveći deo fitomase se nalazi u stablu, dok je veličina krošnji zanemarljiva. Paleotropske močvarne šume se mogu porediti i sa recentnim tropskim kišnim šumama, pre svega stoga što se obe zajednice razvijaju u uslovima vlažne tropske klime. Međutim, mora se uzeti u obzir da struktura recentnih tropskih šuma daleko složenija zahvaljujući raznovrsnim životnim formama koje su razvile različite vrste cvetnica. Diskutovana je i izvesna analogija paleotropskih šuma Lepidodendrales i borealnih četinarskih šuma - tajgi, koja se ogleda u maloj taksonomskoj raznovrsnosti i malom broju edifikatorskih vrsta. U disertaciji su po prvi put iscrpno komentarisana dosadašnja istraživanja Lepidodendrales na Balkanskom poluostrvu. Na osnovu dostupnih podataka florističkih spiskova i paleofitocenoloških podataka većeg broja različitih paleotropskih zajednica Lepidodendrales na području zapadnog i centralnog Balkana, na teritoriji današnjih država Slovenije, Bosne i Hercegovine i Srbije, uradjena je rekonstrukcija mogućeg/pretpostavljenog staništa odgovarajućih paleofitocenoza.sr
dc.descriptionDuring the Carboniferous period, 320-306 million years ago, swamp forests with tree-like lycopsids named Lepidodendrales as edificatory species have developed in the region of tropical belt (paleoequator). The lycopsids belong to the general division of Lycopodiophyta, representing one of the oldest plant groups, and their evolution continues to this day. The oldest lycopsids have appeared about 400 million years ago and their representatives from genera Asteroxylon, Drepanophycus and Baragwanathia belong to the group of first land plants. Lycopodiophyta were also the first land plants to form the phanerophyte life form (genera Cyclostigma and Archaeosigillaria in Upper Devonian, 370 million years ago). During the Carboniferous period, the arboreous lycopsids have reached their maximal development. At that time there were large areas of paleotropical belt covered in swamp forests, where the edificatory species were Lycopodiophyta over 40 m tall. The Carboniferous arboreous lycopsids belonged to order Lepidodendrales and genera Lepidodendron, Synchysidendron, Diaphorodendron, Lepidophloios and Sigillaria. By the end of Carboniferous (about 300 million years ago) all the arboreous lycopsids became extinct, and according to present knowledge the tree-like life forms never appeared again in this group. Today the representatives of Lycopodiophyta are a marginal group of plants, with a minor role and importance in various vegetation lists. Their representatives (Lycopodium, Selaginella, Isoetes etc.) have almost no morphological similarities with the arboreous lycopsids of order Lepidodendrales. The comparative analysis of Lepidodendrales and the recent dendroflora was mostly based on principles of actualism and rules of plant fossilization. The actualistic methods were applied as some basic similarities were noted in development of vegetation in Upper Carboniferous and Neogene/Quaternary. It is particularly important to mention certain factors/events that led to formation and differentiation of different vegetation belts. They include appearance of Carboniferous and Pleistocene Ice Ages, appearance of intensive orogeny (Hercynian/Variscan and Alpine), formation of similar wetland habitats, presence of a tropical vegetation belt, as well as the fact that Carboniferous and Neogene swamp forests have both left behind prominent large amounts of coal. The paleotropical forests dominated by tree-like lycopsids of order Lepidodendrales are representative of particularly important forest vegetation, well-documented by fossils. Its complex ecological importance may be summed in a following way: 1. Unsustainable energetic resources of enormous amounts of Carboniferous coal, mostly originating from stems of Lepidodendrales. 2. Morpho-anatomic characteristics convergent with those of phylogenetically distant land (vascular) seed plants (tree-like habit, branching types, seed-like structures, appearance of monocarpy). This indicates that many of the plant characteristics and life forms (in this case phanerophytes) have appeared independently several times in phylogenetically distant evolutionary lines. 3. The accelerated development of land animals took place only after the formation and development of lush paleotropical forests and appearance of favorable forest microclimates, suitable habitats and almost infinite sources of food. In order to explain development and dynamics of these forests, paleoecological characteristics of certain edificatory genera were analyzed. The reference genera were chosen by number of fossil and literature data and by being previously determined as morphotypes, for example Lepidodendron, Synchysidendron, Diaphorodendron, Lepidophloios and Sigillaria. These genera were compared with structural characteristics of recent representatives of dendroflora, primarily trees and woody seed plants, regarding the general habit, type of branching, height of habit/stem and characteristics of root system. Appearance and role of similar or different morpho-anatomical characteristics in studied fossil Lepidodendrales and referenced representatives of recent dendroflora were used to determine numerous convergent structural characteristics explaining the paleoecological character and importance of extinct Lepidodendrales During the analysis of general habit and height of trees, it was determined that the monocarpous species, particularly the genus Lepidodendron, could reach over 40 m in height (that is the greatest determined height of this genus so far), indicating that certain representatives of Lepidodendrales could reach the height of recent conifers and were taller than many present-day arboreous flowering plants. Analogous heteroblastic and monocarpous characteristics of vegetative and reproductive adult stages were recorded in representatives of ancient genera Lepidodendron, Synchysidendron and Lepidophloios and in recent monocarpous species from families Agavaceae, Bromelidaceae and Asteraceae. The monocarpous Lepidodendrales are showing certain similarities with some giant rosette-bearing (herbaceous) monocarpous plants of genus Agave, which have a pronounced heteroblastic change in habitus during the reproductive stage. As monocarpous representatives of Lepidodendrales remain in the habitat after the reproductive phase, they may also be compared with arboreous monocarpous species of genus Tachigali, which lack the heteroblastic changes but also remain in the habitat for some time after the reproductive phase, providing shelter for young individuals of its species with its stem. Also noted was similarity of heteroblastic changes during the shift from the vegetative to the reproductive stage in Lepidodendrales and shift from the juvenile to the adult stage in recent polycarpous species of genus Pseudopanax. The comparative analyses based on structure and role of leaves and leaf cushions led to conclusion that leaves of Lepidodendrales, periodically excised while leaving leaf bases (cushions) on the stem, are a unique characteristic of order Lepidodendrales and may not be definitively compared with recent plants. On the other hand, there are certain analogous morphological characteristics of main flower parts, primarily the leaf plate and ligula in Lepidodendrales and certain recent plants. The transversal cut of leaf plate of Lepidodendrales is similar to that of certain species of Pinus from Diploxylon group or species from Haploxylon group. The ligula of Lepidodendrales may be compared to some extent to ligula in family Poaceae, primarily due to the similar position – between the leaf and the stem, at the transition between the leaf sheath and blade. The rhizomorph or root system of Lepidodendrales named stigmaria (genus Stigmaria) may be compared with roots of certain recent woody plants from wetland and marsh habitats. It may be assumed that the lateral root shoots of stigmaria had a role in aeration, similar to pneumatophores in roots of present-day species from genera Taxodium, Nyssa, or mangrove vegetation (Rhizophora spp.). In relation to the large number of fossil remains it was concluded that stigmaria were aerial organs or aerial parts of root system, while the underground part, like many other underground plant organs, was not preserved in fossil form. The Ph.D. thesis also includes a comparative analysis of paleotropical forests of Lepidodendrales and corresponding recent forest associations. It was determined that the paleotropical forests show most similarities with the subtropical swamp forests dominated by swamp conifer Taxodium spp. Both these associations, although very distant from each other in time, are characterized by similar swamp soil and similar random distribution and general habitus of edificatory species – the greatest part of phytomass is situated in the bole while the canopy size is negligible. The paleotropical swamp forests may also be compared to the recent tropical rainforests, as both associations develop in conditions of humid tropical climate. However, it must be considered that the structure of recent tropical forest is far more complex due to diverse life forms developed by various species of flowering plants. Also discussed was certain analogy between the paleotropical forests of Lepidodendrales and boreal conifer forest (taiga), expressed in low taxonomic diversity and a small number of edificatory species. This dissertation is the first paper with detailed analysis of all studies on Lepidodendrales performed at Balkan Peninsula. The available data in floristic lists and paleophytocoenological data on a larger number of different paleotropical associations of Lepidodendrales in western and central parts of Balkans (the territories of present-day Slovenia, Bosnia-Herzegovina and Serbia) were used for reconstruction of possible/assumed habitat of appropriate paleophytocoenoses.en
dc.formatapplication/pdf
dc.languagesr
dc.publisherУниверзитет у Београду, Биолошки факултетsr
dc.rightsAutorstvo-Nekomercijalno-Bez prerade 3.0 Srbija (CC BY-NC-ND 3.0)
dc.sourceУниверзитет у Београдуsr
dc.subjectLepidodendronsr
dc.subjectLepidodendronen
dc.subjectLepidophloiossr
dc.subjectSigillariasr
dc.subjectDiaphorodendronsr
dc.subjectSynchyidendronsr
dc.subjectkarbonsr
dc.subjectugaljsr
dc.subjectpaleobotanikasr
dc.subjectpaleoekvatorsr
dc.subjectLepidophloiosen
dc.subjectSigillariaen
dc.subjectDiaphorodendronen
dc.subjectSynchyidendronen
dc.subjectCarboniferousen
dc.subjectcoalen
dc.subjectpaleobotanyen
dc.subjectpaleoequatoren
dc.titlePaleoekologija karbonskih drvenastih prečica reda Lepidodendrales sa posebnim osvrtom na region Balkanskog poluostrvasr
dc.titlePaleoecology of carboniferous arboreous Lycopsids from order Lepidodendrales with special consideration of region of Balkan peninsulaen
dc.typePhD thesis
dcterms.abstractСтевановић, Владимир; Судар, Милан; Стевановић, Бранка; Колар-Јурковшек, Теа; Ђорђевић-Милутиновић, Деса Ђ.; Палеоекологија карбонских дрвенастих пречица реда Лепидодендралес са посебним освртом на регион Балканског полуострва; Палеоекологија карбонских дрвенастих пречица реда Лепидодендралес са посебним освртом на регион Балканског полуострва;


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