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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Silurian-Middle Devonian Acanthodian Faunas of Eastern Australia

Burrow, C. J. Unknown Date (has links)
No description available.
42

An Investigation into the Landscape Ecology and Dynamics of Vegetation Remnants on the Rural Residential Fringe of Brisbane, Australia.

Melville, S. Unknown Date (has links)
No description available.
43

Feeding ecology of shorebirds (CHARADRII) spending the non-breeding season on an Australian subtropical estuarine flat

Zharikov, Y. Unknown Date (has links)
No description available.
44

The dynamics of mangrove forests in relation to die-back and human use in Bunaken National Park, North Sulawesi, Indonesia.

Djamaluddin, R. Unknown Date (has links)
No description available.
45

The ecology of salt lake hydrophytes : the synecology of saline ecosystems and the autecology of the genus Ruppia L. in the South-East of South Australia

Brock, Margaret Anne January 1979 (has links)
v, 191 leaves : ill., photos (some col.) tables, graphs, fold. map ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Zoology, 1980
46

Silurian-Middle Devonian Acanthodian Faunas of Eastern Australia

Burrow, C. J. Unknown Date (has links)
No description available.
47

Silurian-Middle Devonian Acanthodian Faunas of Eastern Australia

Burrow, C. J. Unknown Date (has links)
No description available.
48

Análisis florístico comparativo de la vegetación alto-andina de la Cordillera de la Costa y de los Andes de Chile central.

García Berguecio, Nicolás January 2006 (has links)
Memoria para optar al título profesional de: Ingeniero en Recursos Naturales Renovables / Richness and composition floristical characters of the high-andean vegetation were evaluated among a site in the Coastal (Altos de Chicauma) and Andes (Quilapilún) mountain ranges of central Chile (33º S). The dispersal spectrum of the total floras and the proportion of Chaetanthera species with different pappus types were compared among sites, in order to discern the relevance of the dispersability degree in the origin of the analyzed vegetation in the Coastal mountains. Both richness and composition of species, evaluated in equivalent areas, are not significantly different, although there is a higher proportion of species only present in the Andes than in the Coastal range of central Chile. The dispersability is similar among sites, indicating a low probability of long distance dispersal as the origin of the actual high-andean vegetation in Altos de Chicauma. Aspects relevant to explain the resulting richness and compositional patterns, and the evolution of the high-andean flora, are discussed.
49

Caracterización florística de las formaciones de vegetación de la Región de Arica y Parinacota / Floristic characterization of vegetation formations of Arica and Parinacota Region

Flores Fuentes, Rodrigo Andrés January 2016 (has links)
Memoria para optar al título profesional de Ingeniero Agrónomo / La importancia de conocer la biodiversidad de un determinado lugar, radica en que los seres humanos como sociedad dependemos de los servicios ecosistémicos que nos prestan las diferentes especies. Además, conocer su distribución facilita determinar si están correctamente protegidas y conservadas. Mediante el uso de revisiones bibliográficas, diversas campañas en terreno y la determinación de materiales colectados, se logró establecer que a la fecha existen por lo menos 726 especies de plantas vasculares en la Región de Arica y Parinacota, de las cuales un 90,8% corresponden a especies autóctonas.
50

Caracterização ecológica de sementes e plântulas de árvores de Cerrado

Narváez Zambrano, Ivonne Andrea 29 March 2017 (has links)
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Florestal, 2017. / Submitted by Raquel Almeida (raquel.df13@gmail.com) on 2017-07-12T17:19:01Z No. of bitstreams: 1 2017_IvonneAndreaNarváezZambrano.pdf: 2850341 bytes, checksum: f2207b38a8497495b542c7946ffeeb75 (MD5) / Approved for entry into archive by Raquel Viana (raquelviana@bce.unb.br) on 2017-08-04T19:34:34Z (GMT) No. of bitstreams: 1 2017_IvonneAndreaNarváezZambrano.pdf: 2850341 bytes, checksum: f2207b38a8497495b542c7946ffeeb75 (MD5) / Made available in DSpace on 2017-08-04T19:34:34Z (GMT). No. of bitstreams: 1 2017_IvonneAndreaNarváezZambrano.pdf: 2850341 bytes, checksum: f2207b38a8497495b542c7946ffeeb75 (MD5) Previous issue date: 2017-08-04 / Realizou-se a caracterização ecológica de 37 espécies arbóreas do cerrado, considerando-se 11 atributos funcionais de sementes e plântula. Os teores de água da semente estiveram entre 6-14%. Dezessete espécies tiveram sementes planas, 18 tiveram esféricas e duas alongadas. A massa seca das sementes variou de 2 a 9.175 mg. Astronium fraxinifolium, Tabebuia. aurea, Lafoensia pacari, Aspidosperma macrocarpon e Magonia pubescens tiveram germinação rápida (< 5 dias) e índices de sincronia entre 0,6 - 2,4 bits. Dipterx alata, Luehea paniculata, Kielmeyera speciosa e Cybistax antisyphilitica, tiveram germinação intermediária (5 a 10 dias) e índices de sincronia entre 1,7 - 3,2 bits. Aspidosperma tomentosum, Zeyheria montana, Plathymenia reticulata e Curatella americana, tiveram germinação mais lenta (> 10 dias) e índices de sincronia entre 3,0 - 3,8 bits. Quatro espécies tiveram plântulas do tipo fânero-epígeo-foliáceo (FEF), duas espécies fânero-epígeo-reserva (FER), três espécies fânero-hipógeo-reserva (FHR) e duas espécies cripto-hipógeo-reserva (CHR). A parte aérea das espécies é predominantemente composta por folhas ao invés de crescimento em altura e a parte subterrânea investe mais em alongamento das raízes do que em engrossamento. As espécies apresentam duas estratégias de uso dos recursos, sendo colonizadoras e tolerantes ao estresse. Espécies colonizadoras apresentaram massa da semente menor, raiz principal alongada e alta área foliar específica (SLA). Espécies tolerantes ao estresse apresentaram massa da semente maior, raízes mais curtas e grossas e menor SLA. A caracterização ecológica realizada, indica a diversidade de estratégias das espécies como resposta à heterogeneidade ambiental. O uso de espécies com estratégias para colonizar e para tolerar o estresse na restauração ecológica, pode contribuir à superação de filtros ecológicos, o que aumentaria as espécies capazes de se estabelecer em áreas degradadas. / The ecological characterization of 37 tree species of the cerrado was performed through the measurement of 11 functional attributes in the seed and seedling stages. Seed species had low water contents (6-14%). Seventeen species had flat seeds, 18 spherical seeds and two elongated seeds. Seed dry mass ranged from 2 to 9.175 mg. Astronium fraxinifolium, Tabebuia aurea, Lafoensia pacari, Aspidosperma macrocarpon and Magonia pubescens, had rapid germination ( 10 days) and synchrony indexes between 3.0 - 3.8 bits. Four species had phanero-epigeal-foliaceous (FEF), two phanero-epigeal-reserve (FER), three phanero-hypogeal reserve (FHR) and two crypto-hypogeo-reserve (CHR). Seedlings shoots were mostly composed by leaves instead of growing in height, and roots were relatively longer than thicker. The studied species seem to be divided into two strategies of use of the resources, colonizer and tolerant to stress. Colonizer species had lower seed mass, root elongation and high specific leaf area (SLA). Tolerant to stress species had higher seed mass, shorter roots, lower SLA and thicker roots. This work indicates the diversity of species strategies as a response to environmental heterogeneity. The use of species with colonizer and tolerant to stress strategies to ecological restoration can contribute to the overcoming of ecological filters, which would increase the species capable of establishing themselves in degraded areas.

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