. Sustainable Ecotourism on Islands, with Special Reference to Whale Watching and Marine Protected Areas and Sanctuaries for Cetaceans
Gioria, Margherita & Osborne, Bruce
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- Wade, Max
- Erik Sjoegren
- Osborne, Bruce ; Hickey, Betsy Gioria, Margherita
Gioria, Margherita & Osborne, BruceDepartment of Botany, University College Dublin, Belfield, Dublin 4, Ireland. (margherita.gioria@ucd.ie bruce.osborne@ucd.ie)The invasion of ecosystems by alien plant species is considered a major threat to biodiversity. Alien species are a significant component of the flora of Ireland with approximately 920 alien taxa -nearly as many as the native taxa (1)- recorded over the last 200 years, many of which have become invaders or are potentially invasive. The full impact of invasive species is still poorly understood and, up to now, little attention has been given to their effects on the soil seed bank. The study of soil seed banks is important in invasion ecology because the accumulation of viable seeds in a locality could be one of the most important traits responsible for the persistence of invasive species. Secondly, soil seed banks are a potential source of seeds for the restoration of ecosystems after removal of invasive plants. The proposed study will be primarily focused on the soil seed banks associated with three invasive herbaceous species that are considered established in natural and semi-natural habitats in Ireland: Heracleum mantegazzianum, Fallopia japonica and Gunnera tinctoria. In order to provide a time-dependent assessment of any alterations in the soil seed banks associated with these species, pollen analysis and sediment dating using 210Pb and 137Cs analysis will also be conducted. Reynolds 2002 08.40-09.20 (Keynote -K4). Control and management of alien invasive plants. Wade, MaxRPS, Willow Mere House, Compass Point, Stocks Bridge Way, St Ives, Cambridgeshire, PE27 5JL, UK. (wadem@rpsplc.co.uk).Alien invasive plants have been recognised as having an important negative impact on the indigenous biota, particularly of islands. Effective management and control of these plants is essential for conservation and restoration of native habitats and species. The management and control of such invasions needs to include a number of elements, which recognise the ecology of the invasion process and the autecology of alien invasive and potentially invasive species. Consideration is given to the prediction and prevention of invasion and the management of species, which have become invasive. The latter includes such aspects as biological recording, coordinated control, different control options and the importance of monitoring. Examples of alien species and the approaches taken to achieve their management will be used to develop the principles and best practice in safeguarding the biota of Atlantic islands from alien invasive plants. 09.20-09.40 (O-01) Introduced plants and the reduction of indigenous plant populations in the Azores Islands. Erik SjoegrenEvolutionary Biology Center, Dept. of Plant Ecology, Uppsala University, Villavagen 14, SE 752 36 Uppsala, Sweden (be.sjogren@telia.com).Indigenous plants and vegetation of remote islands are highly susceptible to introduction of alien plant species. Endemic plants and plant communities in the nine Azorean islands have suffered from the introduction during the last 100 yrs of a few highly invasive plants, namely: Cryptomeria japonica (origin China Japan; for production of timber), Pittosporum undulatum (orig. SE. Australia: for creation of hedges), Hedychium gardnerianum (orig. Himalayas; ornamental purposes), Lantana camara (orig. Brazil; ornamental), Gunnera tinctoria (orig. S. America, ornamental). The expansion of these plants has rapidly reduced the areas of typical coastal Myrica faya - Picconia azorica forest and of typical endemic Juniperus brevifolia - Laurus azorica forest of high altitudes above 500 m (cloud-zone forest). Several of the populations of the 65 endemic vascular plants and 27 bryophytes (Azorean and Macaronesian endemics), mostly present in the cloud-zone forests, are today endangered due to expanding areas occupied by introduced plants. The disappearance or severe reduction of populations of native plant species in some of the Azorean islands will progressively lead to genetic erosion making these precious plants less resistant to changes of environmental conditions. 09.40-10.00 (O-22) Gunnera Invasions in Ireland. Osborne, Bruce; Hickey, Betsy & Gioria, MargheritaBotany Department, University College Dublin, Belfield, Dublin 4, Ireland.(Bruce.Osborne@ucd.ie, (margherita.gioria@ucd.ie)Gunnera invasions in Ireland are restricted to one species, G. tinctoria, despite the fact that another, morphologically similar species, G. manicata has been widely cultivated. Although the reason(s) for this specificity is not known it is consistent with the occurrence of invasive plants globally. Greatest abundance of G. tinctoria is in western most regions, characterised by high precipitation and mild winters where frosts are uncommon, a feature also of the global distribution of this and other species within this genus. Within this geographic area, however, invasive plants can be found in a variety of habitats, including coastal zones, bogs, streamsides and wet grasslands. Most extensive colonies are associated with wet grasslands, often associated with earlier agricultural activities. In all cases G.tinctoria plants are associated with rapid early season growth prior to the growth of native species. Isotopic analyses of soils, in conjunction with the identification of Gunnera pollen, suggests that some colonies were present at least 70 years ago, which is broadly consistent with anecdotal evidence. However, reproductive Gunnera plants were presumably present in cultivation in many western areas prior to this, perhaps >150 years ago, indicating a significant lag period before successful establishment in the wild. Whilst the distribution of G. tinctoria in Ireland exhibits a predominantly western oceanic-type distribution, with only a local and regional-specific impact on the native vegetation, recently updated distribution maps have reported significant increases in more central and eastern areas. The reasons for this will be discussed. 10.00-10.20 (O-26) Alien and introduced pteridophytes of Macaronesia – their origins, history, distribution and impact. Download 209.64 Kb. Share with your friends:
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