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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.
1

Is local plant extinction a product of mutualism breakdown? A case study of the Namaqualand spring flora

Smuts, Rowena 07 December 2021 (has links)
A mutualism-centred risk assessment model, proposed by Bond (1993), was used to predict which plant species are vulnerable to extinction in the absence of insect pollinators. The predictions of this model were then compared with actual plant species compositions between adjacent disturbed and undisturbed sites in a Namaqualand flowering community. It was found that autogamous annuals were at the lowest risk of extinction and were consequently abundant in disturbed lands. Geophytes were completely eliminated by ploughing, however, the cause of their local extinction is not necessarily due to mutualism breakdown and may be explained by a lack of seed banks. The model was shown to be useful for predicting distribution patterns for annuals. However, further studies of seed banks, germination cues and colonisation success are necessary to make predictions for the geophytic species. The study illuminated the fact that both plant and associated insect species diversity decline rapidly in disturbed areas and that the elimination of insects, by ploughing, may lead to extensive loss of plant species.
2

La vie et l'oeuvre de Flora Tristan : thèse principale pour le doctorat ès-lettres... /

Puech, Jules-L. January 1925 (has links)
Th.--Lettres--Paris, 1924.
3

Apocynacea do Parque Estadual do Ibitipoca, Minas Gerais, Brasil / Apocynaceae of Ibitipoca State Park, Minas Gerais, Brazil

Bezerra, Lia Monguilhott 10 January 2007 (has links)
Este trabalho apresenta o levantamento das Apocynaceae do Parque Estadual do Ibitipoca. O Parque está situado na Cadeia da Mantiqueira, entre os paralelos 21°40’15" a 21°43’30" S e 43°52’35" a 43°54’15" W. Abriga diversas formações vegetais como cerrados de altitude, florestas montanas e principalmente campos rupestres. A família Apocynaceae, incluindo Asclepiadaceae, é cosmopolita, com ca. de 415 gêneros e 4550 espécies, das quais ca. 870 ocorrem no Brasil, em diferentes hábitats. No Parque ocorrem 10 gêneros e 28 espécies: Aspidosperma olivaceum, A. spruceanum, Blepharodon ampliflorum, Condylocarpon isthmicum, Ditassa acerosa, D. bicolor, D. conceptionis, D. cordata, D. laevis, D. linearis, D. mucronata, D. tomentosa, Forsteronia australis, F. velloziana, Jobinia lindbergii, Mandevilla atroviolacea, M. illustris, M. pohliana, M. sellowii, M. tenuifolia, Oxypetalum appendiculatum, O. insigne, O. lanatum, O. minarum, O. patulum, O. strictum, Peplonia organensis e Tassadia subulata. São apresentados chaves de identificação para os gêneros e espécies, descrições, ilustrações e comentários sobre distribuição e fenologia. / The Apocynaceae species inventory of the Ibitipoca State Park is presented. The Park is located in Mantiqueira Range, between 21°40’15" - 21°43’30" S and 43°52’35" - 43°54’15" W. Within the Park there are several types of vegetation, such as altitude savannas, montane forests and mostly campos rupestres. The Apocynaceae, including Asclepiadoideae, has a cosmopolitan distribution, with about 415 genera and 4550 species, from which about 870 occur in Brazil, in a great range of habitats. 10 genera and 28 species occur in the Park.: Aspidosperma olivaceum, A. spruceanum, Blepharodon ampliflorum, Condylocarpon isthmicum, Ditassa acerosa, D. bicolor, D. conceptionis, D. cordata, D. laevis, D. linearis, D. mucronata, D. tomentosa, Forsteronia australis, F. velloziana, Jobinia lindbergii, Mandevilla atroviolacea, M. illustris, M. pohliana, M. sellowii, M. tenuifolia, Oxypetalum appendiculatum, O. insigne, O. lanatum, O. minarum, O. patulum, O. strictum, Peplonia organensis and Tassadia subulata. Keys for the genera and species, descriptions, illustrations, and comments about the distribution and phenology of the species are presented.
4

Biržulio ežero apyežerio flora ir augalija / Flora and vegetation of Biržulis lake environs

Zimblytė, Giedrė 24 September 2008 (has links)
Biržulio ežero apyežeryje inventorizuota 277 induočių augalų rūšys, priklausančios 71 šeimai ir 51 eilei.Gausiausios augalų rūšimis yra Asteraceae (28 rūšys), Poaceae (25 rūšys), Fabaceae (17 rūšių), Ranunculaceae (16 rūšių), Apiaceae (12 rūšių), Lamiaceae (10 rūšių). Kitose šeimose rasta mažiau nei 10 rūšių. Rastos 5 į Lietuvos RK įrašytos rūšys. Orchis mascula (2 kategorija) – rastos 4 augimvietės ŠR dalyje. Malaxis monophylos (2 kategorija) – vienas individas rastas prie Sąsmaukos miške. Iris sibirica (2 kategorija) – rastos 7 augimvietės rytinėje dalyje, netoli Mažojo Biržulio. Betula humilis (2 kategorija) – randamas rytinėje ir ŠV dalyje. Gausiausi jo sąžalynai yra Mažojo Biržulio pakrantėse. Dactylorhiza incarnata (4 kategorija) – rytinėje ežero dalyje rastos 3 augimvietės. Biržulio ežero apyežeryje aprašyta 36 pievų bendrijos. Šios bendrijos priklauso 4 klasėms, 4 eilėms, 7 sąjungoms ir 14 asociacijų. Biržulio ežero apyežerio Iridetum sibirici Philippi 1960 – įtraukta į LRK augalų bendrijas. Tirtoje teritorijoje rastos ir aprašytos 6 miško bendrijos: Carici elongate - Alnetum glutinosae, Betuletum pubescentis, Betulo – Salicetum repentis, Tilio – Qercetum roboris, Ledo – Pinetum, Salicetum pentandro – cinereae. Aprašytos 5 Iridetum sibirici Philippi 1960 bendrijos. Įvertintas šių bendrijų: sąžalyno atsistatymas, gyvybingumas, žydėjimo ir derėjimo gausa bei ligų ir kenkėjų pažeidimai. Gyvybingiausios Iridetum sibirici Philippi 1960 bendrijos Nr. 1 ir 5. / 277 plant species belonging to 71 families and 51 lines were inventoried in the areas of Lake Biržulis. The richest in the plant species are: Asteraceae (28 species), Poaceae (25 species), Fabaceae (17 species), Ranunculaceae (16 species), Apiaceae (12 species), Lamiaceae (10 species). Les than 10 species were found in other families. 5 species that are written into the Red Book of Lithuania were found. 4 habitats of Orchis mascula (category 2) were found in the North East. One example of Malaxis monophylos (category 2) was found at the isthmus in the forest. 7 habitats of Iris sibirica (category 2) were found in the eastern part, not far from Lake Mažasis Biržulis. Betula humilis (category 2) is localized in the eastern part and in the North West. The richest overgrowths are at the strands of Lake Mažasis Biržulis. 3 habitats of Dactylorhiza incarnata (category 4) were identified in the eastern part of the lake. 36 grassland communities were depicted in the areas of Lake Biržulis. These communities belong to 4 classes, 4 lines, 7 unions and 14 aggregations. Iridetum sibirici Philippi 1960, found in areas of Lake Biržulis, is registered into the plant communities of the Red Book of Lithuania. Also 6 forest communities in the examined area were found and described. They are: Carici elongate - Alnetum glutinosae, Betuletum pubescentis, Betulo – Salicetum repentis, Tilio – Qercetum roboris, Ledo – Pinetum, Salicetum pentandro – cinereae. Moreover, 5 Iridetum sibirici... [to full text]
5

Apocynacea do Parque Estadual do Ibitipoca, Minas Gerais, Brasil / Apocynaceae of Ibitipoca State Park, Minas Gerais, Brazil

Lia Monguilhott Bezerra 10 January 2007 (has links)
Este trabalho apresenta o levantamento das Apocynaceae do Parque Estadual do Ibitipoca. O Parque está situado na Cadeia da Mantiqueira, entre os paralelos 21°40’15” a 21°43’30” S e 43°52’35” a 43°54’15” W. Abriga diversas formações vegetais como cerrados de altitude, florestas montanas e principalmente campos rupestres. A família Apocynaceae, incluindo Asclepiadaceae, é cosmopolita, com ca. de 415 gêneros e 4550 espécies, das quais ca. 870 ocorrem no Brasil, em diferentes hábitats. No Parque ocorrem 10 gêneros e 28 espécies: Aspidosperma olivaceum, A. spruceanum, Blepharodon ampliflorum, Condylocarpon isthmicum, Ditassa acerosa, D. bicolor, D. conceptionis, D. cordata, D. laevis, D. linearis, D. mucronata, D. tomentosa, Forsteronia australis, F. velloziana, Jobinia lindbergii, Mandevilla atroviolacea, M. illustris, M. pohliana, M. sellowii, M. tenuifolia, Oxypetalum appendiculatum, O. insigne, O. lanatum, O. minarum, O. patulum, O. strictum, Peplonia organensis e Tassadia subulata. São apresentados chaves de identificação para os gêneros e espécies, descrições, ilustrações e comentários sobre distribuição e fenologia. / The Apocynaceae species inventory of the Ibitipoca State Park is presented. The Park is located in Mantiqueira Range, between 21°40’15” - 21°43’30” S and 43°52’35” - 43°54’15” W. Within the Park there are several types of vegetation, such as altitude savannas, montane forests and mostly campos rupestres. The Apocynaceae, including Asclepiadoideae, has a cosmopolitan distribution, with about 415 genera and 4550 species, from which about 870 occur in Brazil, in a great range of habitats. 10 genera and 28 species occur in the Park.: Aspidosperma olivaceum, A. spruceanum, Blepharodon ampliflorum, Condylocarpon isthmicum, Ditassa acerosa, D. bicolor, D. conceptionis, D. cordata, D. laevis, D. linearis, D. mucronata, D. tomentosa, Forsteronia australis, F. velloziana, Jobinia lindbergii, Mandevilla atroviolacea, M. illustris, M. pohliana, M. sellowii, M. tenuifolia, Oxypetalum appendiculatum, O. insigne, O. lanatum, O. minarum, O. patulum, O. strictum, Peplonia organensis and Tassadia subulata. Keys for the genera and species, descriptions, illustrations, and comments about the distribution and phenology of the species are presented.
6

The taxonomy of British elms

Armstrong, Jayne Vanessa January 1992 (has links)
No description available.
7

The biodiversity of plantation forestry in Northern Ireland

Kershaw, David January 1998 (has links)
No description available.
8

Studies on the pathogenic mycoflora of selected weeds from the State of Rio de Janeiro (Brazil)

Barreto, Robert Weingart January 1991 (has links)
No description available.
9

Aspects of the agro-ecology of Alopecurus myosuroides Huds

Exley, D. M. January 1985 (has links)
No description available.
10

Systematic studies in Angelica L. and related genera, north east China

Chen, X. Y. January 1985 (has links)
No description available.

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