Ysgol Gwyddorau Amgylcheddol a Naturiol

  1. 2023
  2. Wedi ei Dderbyn / Yn y wasg

    Rapid land cover classification using a 36-year time series of multi-source remote sensing data

    Yan, X., Li, J., Smith, A., Yang, D., Ma, T. & Su, Y., 8 Rhag 2023, (Wedi ei Dderbyn / Yn y wasg) Yn: Land.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  3. Cyhoeddwyd

    Artificial light at night alters predation on colour-polymorphic camouflaged prey

    Moyse, E., Firth, L. B., Smyth, T., Tidau, S. & Davies, T. W., 1 Rhag 2023, Yn: Basic and Applied Ecology. 73, t. 88-93

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  4. Cyhoeddwyd

    Improved representation of cattle herd dynamics for bio-physical modelling of pathways to a climate neutral land sector

    Henn, D., Humphreys, J., Duffy, C., Gibbons, J. & Styles, D., 1 Rhag 2023, Yn: Agricultural Systems. 212, 103772.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  5. Cyhoeddwyd

    Increasing Biodiversity in Livestock Production Systems: Plant Traits and Natural Regeneration Capacity of Woody Vegetation in Actively Managed Grasslands

    Sheik, M. J. E., Finegan, B., Healey, J. & Casonoves, F., 1 Rhag 2023, Silvopastoral systems of Meso America and Northern South America: Chará, J. & Jose, S. (eds) . Chara, J. & Jose, S. (gol.). Springer Nature Switzerland AG, t. 279-305

    Allbwn ymchwil: Pennod mewn Llyfr/Adroddiad/Trafodion CynhadleddPennodadolygiad gan gymheiriaid

  6. E-gyhoeddi cyn argraffu

    Lateglacial and early Holocene evolution of the Tyne Valley in response to climatic shifts and possible paraglacial landscape legacies

    Yorke, L., Chiverrell, R. & Schwenninger, J-L., 1 Rhag 2023, (E-gyhoeddi cyn argraffu) Yn: Geomorphology.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  7. Cyhoeddwyd

    Relational values in locally adaptive farmer-to-farmer extension: how important?

    Martini, E., Pagella, T., Mollee, E. & van Noordwijk, M., 1 Rhag 2023, Yn: Current Opinion in Environmental Sustainability. 65, 101363.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  8. Wedi ei Dderbyn / Yn y wasg

    Restless nights when sick: ectoparasite infections alter rest-activity cycles of diurnal fish hosts

    Arapi, E., Reynolds, M., Ellison, A. & Cable, J., 1 Rhag 2023, (Wedi ei Dderbyn / Yn y wasg) Yn: Parasitology.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  9. Cyhoeddwyd

    “You don't have to perform for the trees”: The longer-term effects of nature-based interventions on wellbeing

    Gittins, H., Dandy, N., Wynne-Jones, S. & Morrison, V., 1 Rhag 2023, Yn: Wellbeing, Space & Society. 5, 100160.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  10. Cyhoeddwyd

    Biochar application to temperate grasslands: challenges and opportunities for delivering multiple ecosystem services

    Brown, R., Chadwick, D., Bott, T., West, H., Wilson, P., Hodgins, G., Snape, C. & Jones, D. L., Rhag 2023, Yn: Biochar. 5, 1, 33.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  11. Cyhoeddwyd

    Continuous Cover Forestry and Remote Sensing : A Review of Knowledge Gaps, Challenges, and Potential Directions

    Stoddart, J., Suarez, J., Mason, W. & Valbuena, R., Rhag 2023, Yn: Current Forestry Reports. 9, 6, t. 490-501 12 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  12. Cyhoeddwyd

    Diurnal changes in pathogenic and indicator virus concentrations in wastewater

    Farkas, K., Pântea, I., Woodhall, N., Williams, D., Lambert-Slosarska, K., Williams, R. C., Grimsley, J. M. S., Singer, A. C. & Jones, D. L., Rhag 2023, Yn: Environmental Science and Pollution Research. 30, 59, t. 123785-123795 11 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  13. Cyhoeddwyd

    Researching Green Process Innovation Across Borders and Boundaries Through Collaborative Inquiry

    Coughlan, P., Bellini, R., Bello-Dambatta, A., Dallison, R., Dreyer-Gibney, K., Gallagher, J., Harris, I., McNabola, A., Mitrovic, D., Murali, M., Novara, D., Patil, S., Rigby, A., Ritsos, P. D., Schestak, I., Singh, A., Walker, N. & Williams, P., Rhag 2023, Yn: The Journal of Applied Behavioral Science. 59, 4, t. 556-584 29 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  14. Cyhoeddwyd

    Environmental DNA biomonitoring in biodiversity hotspots: A case study of fishes of the Okavango Delta

    von der Heyden, S., Neef, G., Grevesse, T., Cwecwe, Y., Sado, T., Miya, M., Mosie, I., Creer, S., Skelton, P. & von Brandis, R., 28 Tach 2023, Yn: Environmental DNA. 5, 6, t. 1720-1731

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  15. Cyhoeddwyd

    VarLOCK: sequencing-independent, rapid detection of SARS-CoV-2 variants of concern for point-of-care testing, qPCR pipelines and national wastewater surveillance

    Nan, X., Hardinge, P., Hoehn, S., Dighe, S. N., Ukeri, J., Pease, D. F., Griffin, J., Warrington, J. I., Saud, Z., Hottinger, E., Webster, G., Jones, D., Kille, P., Weightman, A., Stanton, R., Castell, O. K., Murray, J. A. H. & Jurkowski, T. P., 27 Tach 2023, Yn: Scientific Reports. 13, 1, 20832.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  16. E-gyhoeddi cyn argraffu

    Comparative population genomics of manta rays has global implications for management

    Humble, E., Hosegood, J., Carvalho, G., De Bruyn, M., Creer, S., Stevens, G. M. W., Armstrong, A., Bonfil, R., Deakos, M., Fernando, D., Froman, N., Peel, L. R., Pollett, S., Ponzo, A., Stewart, J. D., Wintner, S. & Ogden, R., 23 Tach 2023, (E-gyhoeddi cyn argraffu) Yn: Molecular Ecology.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  17. Cyhoeddwyd

    Monitoring SARS-CoV-2 Using Infoveillance, National Reporting Data, and Wastewater in Wales, United Kingdom: Mixed Methods Study

    Cuff, J. P., Dighe, S. N., Watson, S. E., Badell-Grau, R. A., Weightman, A. J., Jones, D. L. & Kille, P., 23 Tach 2023, Yn: JMIR infodemiology. 3, e43891.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  18. Cyhoeddwyd

    Tropical forest loss from growing rubber trade is more substantial than previously thought – new research

    Warren-Thomas, E. & Ahrends, A., 21 Tach 2023, The Conversation.

    Allbwn ymchwil: Cyfraniad at gyhoeddiad arbenigolErthygl

  19. Cyhoeddwyd

    Inequalities in noise will affect urban wildlife

    Nelson-Olivieri, J. R., Layden, T. J., Antunez, E., Khalighifar, A., Lasky, M., Laverty, T. M., Sanchez, K. A., Shannon, G., Starr, S., Verahrami, A. K. & Bombaci, S. P., 20 Tach 2023, Yn: Nature Ecology and Evolution.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  20. Cyhoeddwyd

    Long-term satellite observations show continuous increase of vegetation growth enhancement in urban environment

    Peng, X., Jiang, S., Liu, S., Valbuena, R., Smith, A., Zhan, Y., Shi, Y., Ning, Y., Feng, S., Gao, H. & Wang, Z., 10 Tach 2023, Yn: Science of the Total Environment. 898, 165515.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  21. Cyhoeddwyd

    Amazonian secondary forests are greatly reducing fragmentation and edge exposure in old-growth forests

    Smith, C., Barlow, J., Schwartz, N., Healey, J., Young, P. & Miranda, L., 9 Tach 2023, Yn: Environmental Research Letters. 18, 12, 124016.

    Allbwn ymchwil: Cyfraniad at gyfnodolynLlythyradolygiad gan gymheiriaid

  22. Cyhoeddwyd

    Horizontal viewsheds of large herbivores as a function of woodland structure

    Gresham, A., Healey, J., Eichhorn, M., Barton, O., Smith, A. & Shannon, G., 9 Tach 2023, Yn: Ecology and Evolution. 13, 11

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  23. Cyhoeddwyd

    A horizon scan of issues affecting UK forest management within 50 years

    Tew, E. R., Ambrose-Oji, B., Beatty, M., Buntgen, U., Butterworth, H., Clover, G., Cook, D., Dauksta, D., Day, W., Deakin, J., Field, A., Gardiner, B., Harrop, P., Healey, J., Heaton, R., Hemery, G., Hill, L., Hughes, O., Khaira-Creswell, P. K., Kirby, K., Leitch, A., MacKay, J., McIlhiney, R., Murphy, B., Newton, L., Norris, D., Nugee, R., Parker, J., Petrokofsky, G., Prosser, A., Quine, C., Randhawa, G., Reid, C., Richardson, M., Ridley-Ellis, D. J., Riley, R., Roberts, J. E., Schaible, R., Simpson, L. E., Spake, R., Tubby, I., Urquhart, J., Wallace-Stephens, F., Wilson, J. D. & Sutherland, W. J., 8 Tach 2023, Yn: Forestry.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  24. Cyhoeddwyd

    100 years of anthropogenic impact causes changes in freshwater functional biodiversity

    Eastwood, N., Zhou, J., Derelle, R., Abdallah, M. A-E., Stubbings, W. A., Jia, Y., Crawford, S. E., Davidson, T. A., Colbourne, J. K., Creer, S., Bik, H., Hollert, H. & Orsini, L., 7 Tach 2023, Yn: Elife. 12

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  25. Cyhoeddwyd

    Assessing the effectiveness, practicality and cost effectiveness of mitigation measures to reduce greenhouse gas emissions from intensively cultivated peatlands

    Rhymes, J. M., Arnott, D., Chadwick, D. R., Evans, C. D. & Jones, D. L., 1 Tach 2023, Yn: Land Use Policy. 134, 106886.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  26. Cyhoeddwyd

    Development and validation of a duplex RT-qPCR assay for norovirus quantification in wastewater samples

    Alex-Sanders, N., Woodhall, N., Farkas, K., Scott, G., Jones, D. L. & Walker, D. I., 1 Tach 2023, Yn: Journal of Virological Methods. 321, 114804.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  27. Cyhoeddwyd

    Environmental DNA metabarcoding for fish diversity assessment in a macrotidal estuary: A comparison with established fish survey methods

    Gibson, T., Carvalho, G., Ellison, A., Gargiulo, E., Hatton-Ellis, T., Handley, L. L., Mariani, S., Collins, R. A., Sellers, G., Distaso, M., Zampieri, C. & Creer, S., 1 Tach 2023, Yn: Estuarine, Coastal and Shelf Science. 294, 108522.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  28. Cyhoeddwyd

    Evaluation of machine learning methods and multi-source remote sensing data combinations to construct forest above-ground biomass models

    Yan, X., Li, J., Smith, A., Yang, D., Ma, T., Su, Y. & Shao, J., 1 Tach 2023, Yn: International Journal of Digital Earth. 16, 2, t. 4471-4491 21 t., 4471-4491.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  29. Cyhoeddwyd

    Run-of-river hydropower in the UK and Ireland: The case for abstraction licences based on future flows

    Dallison, R. & Patil, S., 1 Tach 2023, Yn: Environmental Research: Infrastructure and Sustainability. 3, 4, 045005.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  30. E-gyhoeddi cyn argraffu

    Migratory bats are sensitive to magnetic inclination changes during the compass calibration period

    Schneider, W. T., Holland, R. A., Keišs, O. & Lindecke, O., Tach 2023, (E-gyhoeddi cyn argraffu) Yn: Biology letters. 19, 11, t. 20230181

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  31. Cyhoeddwyd

    Predicting the spatial expansion of an animal population with presence-only data

    Barton, O., Healey, J., Cordes, L., Davies, A. & Shannon, G., Tach 2023, Yn: Ecology and Evolution. 13, 11, t. e10778 e10778.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  32. Cyhoeddwyd

    One-pot chemo-enzymatic synthesis and one-step recovery of length-variable long-chain polyphosphates from microalgal biomass

    Lin, Y-H., Nishikawa, S., Jia, T. Z., Yeh, F-I., Khusnutdinova, A., Yakunin, A., Fujishima, K. & Wang, P-H., 27 Hyd 2023, Yn: Green Chemistry. 23

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  33. Cyhoeddwyd

    Circular wood use can accelerate global decarbonisation but requires cross-sectoral coordination

    Forster, E., Healey, J., Newman, G. & Styles, D., 25 Hyd 2023, Yn: Nature Communications. 14, 1, 6766.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  34. Cyhoeddwyd

    Drought-related mortality modifies mixing effects on light absorption and growth in mono-specific and mixed stands of Fagus sylvatica, Alnus glutinosa and Betula pendula.

    Plaga, B., Bauhus, J., Smith, A., Gonzalez Pereira, M. & Forrester, D., 23 Hyd 2023, Yn: Forestry.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  35. Cyhoeddwyd

    High-resolution maps show that rubber causes substantial deforestation

    Wang, Y., Hollingsworth, P. M., Zhai, D., West, C., Green, J. M. H., Chen, H., Hurni, K., Su, Y., Warren-Thomas, E., Xu, J. & Ahrends, A., 18 Hyd 2023, Yn: Nature. 623

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  36. Cyhoeddwyd

    Ancient Egypt had far more venomous snakes than the country today, according to our new study of a scroll

    Winder, I. C. & Wüster, W., 16 Hyd 2023, The Conversation.

    Allbwn ymchwil: Cyfraniad at gyhoeddiad arbenigolErthygl

  37. Cyhoeddwyd

    One hundred priority questions for the development of sustainable food systems in sub-Saharan Africa

    Devenish, A. J., Schmitter, P., Jellason, N. P., Esmail, N., Abdi, N. M., Barron, J., Chapman, A. S. A., Chausson, A. M., Chibesa, M., Reading, U., Dugan, E., Edwards, G. I., Egeru, A., Gebrehiwot, T., Griffiths, G. H., Haile, A., Hunga, H. G., Igbine, L., Jarju, O. M., Keya, F., Khalifa, M., Ledoux, W. A., Lejissa, L. T., Loupa, P., Lwanga, J., Mapedza, E. D., Marchant, R., McLoud, T., Mukuyu, P., Musah, L. M., Mwanza, M., Mwitwa, J., Neina, D., London, U., Njogo, S., Robinson, E. J. Z., Singini, W., Umar, B. B., Wesonga, F., Willcock, S., Yang, J. & Tobias, J. A., 7 Hyd 2023, Yn: Land. 39 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  38. E-gyhoeddi cyn argraffu

    What bit the Ancient Egyptians? Niche modelling to identify the snakes described in the Brooklyn medical papyrus

    McBride, E., Winder, I. C. & Wüster, W., 7 Hyd 2023, (E-gyhoeddi cyn argraffu) Yn: Environmental Archaeology.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  39. Cyhoeddwyd

    Cross-validation for geospatial data: Estimating generalization performance in geostatistical problems

    Wang, J., Hopkins, L., Hallman, T., Robinson, W. D. & Hutchinson, R., 4 Hyd 2023, Yn: Transactions on Machine Learning Research.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  40. Cyhoeddwyd

    Capturing red squirrels (Sciurus vulgaris) on camera: A cost-effective approach for monitoring relative abundance and habitat preference

    Shannon, G., Valle, S. & Shuttleworth, C., 3 Hyd 2023, Yn: Ecology and Evolution. 13, 10, e10536.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  41. Cyhoeddwyd

    Environmental and land use consequences of replacing milk and beef with plant-based alternatives

    Porto Costa, M., Saget, S., Zimmermann, B., Petig, E., Rees, R. M., Chadwick, D., Gibbons, J., Shrestha, S., Williams, M. & Styles, D., 1 Hyd 2023, Yn: Journal of Cleaner Production. 424, 138826.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  42. Cyhoeddwyd

    Photocatalytic fixation of NOx in soils

    Sánchez-Rodríguez, A. R., Gómez-Álvarez, E., Méndez, J. M., Skiba, U. M., Jones, D. L., Chadwick, D. R., Del Campillo, M. C., Fernandes, R. B., Kleffmann, J. & Barrón, V., 1 Hyd 2023, Yn: Chemosphere. 338, 139576.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  43. Cyhoeddwyd

    National scale mapping of supply and demand for recreational ecosystem services

    Hooftman, D., Ridding, L., Redhead, J. & Willcock, S., Hyd 2023, Yn: Ecological Indicators. 154, 20 t., 110779.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  44. Cyhoeddwyd

    Structural insights into hydrolytic defluorination of difluoroacetate by microbial fluoroacetate dehalogenases

    Khusnutdinova, A. N., Batyrova, K., Brown, G., Fedorchuck, T., Chai, Y. S., Skarina, T., Flick, R., Petit, A-P., Savchenko, A., Stogios, P. & Yakunin, A., Hyd 2023, Yn: Febs Journal. 290, 20, t. 4966-4983 18 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  45. E-gyhoeddi cyn argraffu

    Voluntary thermal maximum of grassland vipers (Vipera spp.): environmental drivers and local adaptation

    Radovics, D., Sos, T., Mebert, K., Üveges, B., Budai, M., Rák, G., Szabolcs, M., Lengyel, S. & Mizsei, E., 30 Medi 2023, (E-gyhoeddi cyn argraffu) Yn: Zoological Journal of the Linnean Society.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  46. Cyhoeddwyd

    Synthesis and thermal studies of two phosphonium tetrahy-droxidohexaoxidopentaborate(1-) salts: single-crystal XRD characterization of [iPrPPh3][B5O6(OH)4].3.5H2O and [MePPh3][B5O6(OH)4].B(OH)3.0.5H2O

    Beckett, M., Horton, P., Hursthouse, M. B. & Timmis, J., 29 Medi 2023, Yn: Molecules. 28, 19, 12 t., 6867.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  47. Cyhoeddwyd

    Evidence for cryptic sex in parthenogenetic stick insects of the genus Timema

    Freitas, S., Parker, D. J., Labédan, M., Dumas, Z. & Schwander, T., 27 Medi 2023, Yn: Proceedings of the Royal Society B: Biological Sciences. 290, 2007, 11 t., 20230404.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  48. Cyhoeddwyd

    Museum DNA reveals a new, potentially extinct species of rinkhals (Serpentes: Elapidae: Hemachatus) from the Eastern Highlands of Zimbabwe

    Major, T., Renk, P., Reissig, J., Paijmans, J., Morris, E., Hofreiter, M., Barlow, A., Broadley, D. G. & Wüster, W., 27 Medi 2023, Yn: PLoS ONE. 18, 9, 19 t., e0291432.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  49. Cyhoeddwyd

    Enjoying inequality

    Wilson, J., 26 Medi 2023, Clickbait capitalism: Economies of Desire in the Twenty-First Century. Samman, A. & Gammon, E. (gol.). Manchester University Press

    Allbwn ymchwil: Pennod mewn Llyfr/Adroddiad/Trafodion CynhadleddPennodadolygiad gan gymheiriaid

  50. E-gyhoeddi cyn argraffu

    Biological knowledge shortfalls impede conservation efforts in poorly studied taxa—A case study of Laboulbeniomycetes

    Haelewaters, D., Matthews, T. J., Wayman, J. P., Cazabonne, J., Heyman, F., Quandt, C. A. & Martin, T. E., 23 Medi 2023, (E-gyhoeddi cyn argraffu) Yn: Journal of Biogeography. 51, 1, t. 29-39 11 t.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

  51. Cyhoeddwyd

    Nature positive must incorporate, not undermine, the mitigation hierarchy

    Maron, M., Quétier, F., Sarmiento, M., ten Kate, K., Evans, M. C., Bull, J. W., Jones, J. P. G., zu Ermgassen, S. O. S. E., Milner-Gulland, E. J., Brownlie, S., Treweek, J. & von Hase, A., 21 Medi 2023, Yn: Nature Ecology and Evolution.

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid