993 resultados para Marine painting, British.


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It has traditionally been considered that areas with high natural species richness are likely to be more resistant to non-indigenous species than those with lower numbers of species. However, this theory has been the subject of a debate over the last decade, since some studies have shown the opposite trend. In the present study, a macroalgal survey was carried out at 24 localities in Northern Ireland and southern England, using a quadrat approach in the lower littoral. The two opposing hypotheses were tested (negative versus positive relationship between native and non-indigenous species richness) in this marine environment. The effect of the presence of 'impacts', potential sources of disturbance and species introduction (e.g. marina, harbour or aquaculture), was also tested. A positive relationship was found between the number of non-indigenous species and the native species richness at the three different scales tested (quadrats, sites and localities). At no scale did a richer native assemblage appear to restrict the establishment of introduced species. The analyses revealed greater species richness and different community composition, as well as more non-indigenous species, in southern England relative to Northern Ireland. The presence of the considered impacts had an effect on the community composition and species richness in southern England but not in Northern Ireland. Such impacts had no effect on the non-indigenous species richness in either area.

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The diminutive marine red alga Antithamnion densum (Suhr) Howe (Ceramiales, Rhodophyta), previously known in the north Atlantic from three sites in north-western France, is reported from the subtidal of a wave-exposed site at Clare I., Co. Mayo, Ireland, where it grows epiphytically on various macroalgae. The previously restricted distribution of this species in the North Atlantic gave rise to speculation that it represented an introduced plant. The geographical isolation of the Irish locality and the restricted habitat in which plants were found suggests that A. densum may be native to the north eastern Atlantic. However, the finding of the Trailliella-phase of the adventive red alga Bonnemaisonia hamifera Hariot at Clare I. in 1911, shortly after it had been discovered on the south coast of England, indicates the potential for the transport of introduced species to the west coast of Ireland.

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Sedjrrlents deposited in the Late Quaternary marine sUbrnergences that follov'ted the deglaciation of Ontario} Quebec., and 6ritlst-1 Columbia often contaln an abundant nlarlne invertebrate macrofauna. The rnacrofauna~ dotYllnated by aragonitic pelecypods} is fully preserved In their original mineralogy and cherrlistry 8S deternl1ned by x-ray dlffractlon., scannlng electron tl-,lcroscoDY., trace and r1l1 nor elet11ent analyses and stable isotopes. Ttle trace elernent and stable isotope geochen-Ilstry of chernlcal1y unaltered aragorlitlc molluscs can be used to determine paleoter1-lperatures and paleosallnltles." HO\Never} corrections need to be tllade \fvtlen deterrTIlnlng oxygen-isotope paleotenlperi:ttures due to the lnfluence of isotopically 11gtlt glaciol rneltv-laters and reduced sal1nltles. Ttle eastern Laurentide Ice Sheet probably had an o:~ygen lS0tOP1C composition as low as -8e) 0/00 (Sr1[IW). In additl0fl} corrections need to be rnade to the carbonlsotope values, before salinity deterrnlnatlons are t11ade., due to the reJjuctlon of the terrestrial carbon bl0rnass during glac1al maxlrna. Using geochernlcal data frot11 537 marlne n-'8crolnvertebrates frorTI 72 localities in soutt-,easter Ontarl0 and southern Quebec, it tras been deterrnined that the Late Quaternary Char1lplaln Sea \N6S density stratified along salinity and temperatlJre gradients. The deep-\h/aters of tt-,e Charnplaln Sea tlad salinities that ranged frorn 31 to 36 ppt} and terrlperatures of 00 to 5°C. Conversely.. the st1alloy./-\f*later regirrle of ttle Ctlarnplaln Sea tlad sal1nltles that ranged fron-, 24 to 33 ppt} Y.tltt1 terrlperatures ranglng from 5° to 15°C. Tr,8 rrlajorl rnlnor1 and trace e1et1-,ent geochernlcal analysls of 155 marine lnvertebrates frorn 4 10C611t1es of tt-,e Late Quaternary Ft. Langley Forrnatlon and Capl1ano Sedlments;. souttl\Nestern Brltlsh Columblal suggest l t~lat the 'waters of the o-,arlne lnundation that fol1o....ved the retreating Cordl11eran Ice Sheet had sal1nltles ranglng frorn 32 to 3f. DPt.

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Owing to their high vulnerability and low adaptive capacity, Caribbean islands have legitimate concerns about their future, based on observational records, experience with current patterns and consequences of climate variability, and climate model projections. Although emitting less than 1% of global greenhouse gases, islands from the region have already perceived a need to reallocate scarce resources away from economic development and poverty reduction, and towards the implementation of strategies to adapt to the growing threats posed by global warming (Nurse and Moore, 2005). The objectives of this Report are to conduct economic analyses of the projected impacts of climate change to 2050, within the context of the IPCC A2 and B2 scenarios, on the coastal and marine resources of the British Virgin Islands (BVI). The Report presents a valuation of coastal and marine services; quantitative and qualitative estimates of climate change impacts on the coastal zone; and recommendations of possible adaptation strategies and costs and benefits of adaptation. A multi-pronged approach is employed in valuing the marine and coastal sector. Direct use and indirect use values are estimated. The amount of economic activity an ecosystem service generates in the local economy underpins estimation of direct use values. Tourism and fisheries are valued using the framework developed by the World Resources Institute. Biodiversity is valued in terms of the ecological functions it provides, such as climate regulation, shoreline protection, water supply erosion control and sediment retention, and biological control, among others. Estimates of future losses to the coastal zone from climate change are determined by considering: (1) the effect of sea level rise on coastal lands; and (2) the effect of a rise in sea surface temperature (SST) on coastal waters. Discount rates of 1%, 2% and 4% are employed to analyse all loss estimates in present value terms. The overall value for the coastal and marine sector is USD $1,606 million (mn). This is almost 2% larger than BVI’s 2008 GDP. Tourism and recreation comprise almost two-thirds of the value of the sector. By 2100, the effects of climate change on coastal lands are projected to be $3,988.6 mn, and $2,832.9 mn under the A2 and B2 scenarios respectively. In present value terms, if A2 occurs, losses range from $108.1-$1,596.8 mn and if B2 occurs, losses range from $74.1-$1,094.1 mn, depending on the discount rate used. Estimated costs of a rise in SST in 2050 indicate that they vary between $1,178.0 and $1,884.8 mn. Assuming a discount rate of 4%, losses range from $226.6 mn for the B2 scenario to $363.0 mn for the A2 scenario. If a discount rate of 1% is assumed, estimated losses are much greater, ranging from $775.6-$1,241.0 mn. Factoring in projected climate change impacts, the net value of the coastal and marine sector suggests that the costs of climate change significantly reduce the value of the sector, particularly under the A2 and B2 climate change scenarios for discount rates of 1% and 2%. In contrast, the sector has a large, positive, though declining trajectory, for all years when a 4% discount rate is employed. Since the BVI emits minimal greenhouse gases, but will be greatly affected by climate change, the report focuses on adaptation as opposed to mitigation strategies. The options shortlisted are: (1) enhancing monitoring of all coastal waters to provide early warning alerts of bleaching and other marine events; (2) introducing artificial reefs or fish-aggregating devices; (3) introducing alternative tourist attractions; (4) providing retraining for displaced tourism workers; and (5) revising policies related to financing national tourism offices to accommodate the new climatic realities. All adaptation options considered are quite justifiable in national terms; each had benefit-cost ratios greater than 1.

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2, Plates

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Mode of access: Internet.

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Imprint varies. No. 24-34 published: Liverpool : Liverpool University Press.