Search for dissertations about: "ecological succession"

Showing result 1 - 5 of 36 swedish dissertations containing the words ecological succession.

  2. 1. Long-term studies of succession : Colonisation and seed banks

    Author : Ulf Grandin; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ellenberg indicator values; genetic variation; long-term study; Lythrum salicaria; Moehringia trinervia; primary succession; seed bank; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Abstract : Using data from long-term studies of the vegetation in two areas under primary succession, patterns of colonisation and the accumulated seed bank during plant succession were studied.At century-old small islands in Lake Hjälmaren, Sweden, the genetic structure of differently old populations of Moehringia trinervia and Lythrum salicaria was studied, using allozyme variation for M. READ MORE

  4. 2. Ecological rehabilitation of degraded hill slopes in southern Wello, Ethiopia

    Author : Kebrom Tekle; Ingvar Backéus; Eddy van der Maarel; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; Classification; hillside closures; intercept lengths; land cover; land degradation; local participation; natural regeneration; ordination; permanent plots; soil seed banks; succession; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Ecological Botany; Ekologisk botanik;

    Abstract : Clearing of vegetation has left large areas of southern Wello (Ethiopia) at a high risk ofland degradation. In this study, the causes, extent and consequences of land degradationproblems are reviewed. To see land cover changes, aerial photographs from 1958 and1986 were compared with the help of a GIS procedure. READ MORE

  5. 3. Peatland Bryophytes in a Changing Environment : Ecophysiological Traits and Ecosystem Function

    Author : Gustaf Granath; Håkan Rydin; Joachim Strengbom; Steven K Rice; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; allometric scaling; chlorophyll fluorescence; competition; decomposition; flooding; mire; N concentration; nitrogen deposition; photosynthesis; succession; stoichiometry; Ecological Botany; Ekologisk botanik;

    Abstract : Peatlands are peat forming ecosystems in which not fully decomposed plant material builds up the soil. The sequestration of carbon into peat is mainly associated with the bryophyte genus Sphagnum (peat mosses), which dominate and literally form most peatlands. READ MORE

  6. 4. Vegetation changes on Swedish mires : Effects of raised temperature and increased nitrogen and sulphur influx

    Author : Urban Gunnarsson; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Acidification; growth; long-term studies; mires; nitrogen; species richness; Sphagnum; succession; sulphur; temperature; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; ekologisk botanik; Ecological Botany;

    Abstract : Since the start of the industrialisation, the deposition of nitrogen and sulphur and the atmospheric concentrations of greenhouse gases have increased. The main objectives of this study were to find how these changes in climate and deposition can change the vegetation of mire ecosystems and the growth of Sphagnumspecies. READ MORE

  7. 5. Ecological succession of benthic macrofauna following disturbance : Effects of contaminants and in situ sediment remediation

    Author : Caroline Raymond; Jonas S. Gunnarsson; Agnes M. L. Karlson; Francisco J. A. Nascimento; Joanna Norkko; Gert Van Hoey; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Activated carbon; Benthos; Bioturbation; Contaminants; Environmental indices; Environmental monitoring; Environmental quality; Seafloor integrity; Sediment remediation; marin ekologi; Marine Ecology;

    Abstract : More than 70% of the Earth is covered by water, and most of the sea floor consists of soft sediments, such as mud, clay and sand. Thus, soft sediments form one of the most important habitats on Earth, with a high diversity of organisms. READ MORE