Anifeiliaid ymledol a’u heffeithiau ar ecosystemau dŵr croyw Prydain

Anifeiliaid ymledol a’u heffeithiau ar ecosystemau dŵr croyw Prydain
John Rhidian Thomas a Siân Griffiths

Cyflwyno rhywogaethau anfrodorol yw un o’r bygythiadau mwyaf sylweddol a wyneba bioamrywiaeth byd eang. Ceir effaith sylweddol ar ecosystemau dŵr croyw, oherwydd cyflwynir nifer fawr o rywogaethau i lynnoedd ac afonydd ar gyfer dyframaethu a physgota. Yn yr erthygl hon, disgrifir yr anifeiliaid dŵr croyw anfrodorol hynny sy’n bresennol ac yn ymledu ym Mhrydain, neu sy’n debygol o ymsefydlu dros y blynyddoedd nesaf. Esbonnir sut effaith y caiff yr anifeiliaid hyn ar ecosystemau dŵr croyw ac economi Prydain, gan hefyd amlygu’r problemau hynny sy’n dod i’r amlwg wrth geisio rheoli’r ymledwyr. Trafodir hefyd sut y bydd newid hinsawdd a bygythiadau eraill yn effeithio ar ddosbarthiad rhywogaethau ymledol yn y dyfodol.


  	John Rhidian Thomas a Siân W. Griffiths, ‘Anifeiliaid ymledol a’u heffeithiau ar ecosystemau dŵr croyw Prydain’, Gwerddon, 25, Hydref 2017, 7–29.


    Rhywogaethau ymledol, anifeiliaid dŵr croyw, ecosystemau, cimwch yr afon, pysgod, ymledwyr, cynefinoedd, afonydd, Prydain.


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