54:
176:
31:
20:
42:
285:
Used as a soil conditioner, it is dredged from the sea floor and crushed to a powder. The slow growth of individual nodules and their accumulation in beds over a millennial timescale means that there is no possibility of maerl keeping up with dredging for this purpose. Maerl should be considered as a
261:
Maerl has been extracted for centuries mainly for use as an agricultural fertilizer. The amount extracted increased in the late 20th century and in 2000, maerl was extracted at c. 5,000 tonnes per year in
Ireland and c. 500,000 tonnes per year in France. Large scale maerl extraction over the past 40
91:
In Europe maerl beds occur throughout the
Mediterranean, along most of the Atlantic coast from Portugal to Norway, and in the English Channel, Irish Sea and North Sea. The distribution of maerl is dependent on water movement, light and salinity concentration. Maerl beds occur in the
78:
with a certain growth habit. Maerl grows at a rate of c. 1 mm per year. It accumulates as unattached particles and forms extensive beds in suitable sublittoral sites. The term maerl originally refers to the branched growth form of
Lemoine (1910) and
96:, and can be found to around 30 m depth in the British Isles and up to 120 m deep in the Mediterranean. Maerl deposits can reach up to 10 m thick, but are usually much thinner; carbon dating has shown that they can be more than 5500 years old.
1041:
617:
Blunden, G.; Farnham, W. F.; Jephson, N.; Barwell, C. J.; Fenn, R. H.; Plunkett, B. A. (1981). "The
Composition of Maȅrl Beds of Economic Interest in Northern Brittany, Cornwall and Ireland". In Levrig, Tore (ed.).
805:
Steller, D.L., Riosmena-Rodríguez, R., Foster, M.S., Roberts, C.A. (2003). "Rhodolith bed diversity in the Gulf of
California: the importance of rhodolith structure and consequences of disturbance".
1038:
592:
214:
with a variety of niches that support high associated invertebrate and algal biodiversity. Maerl beds act as nursery areas for the juvenile stages of commercial species such as juvenile
451:
Grall, J., Le Loc'h, F., Guyonnet, B., and Riera, P. (2006) "Community structure and food web based on stable isotopes (δ15N and δ13C) analysis of a North
Eastern Atlantic maerl bed".
892:
Wilson, S.; Blake, C.; Berges, J. A.; Maggs, C. A. (November 2004). "Environmental tolerances of free-living coralline algae (maerl): implications for
European marine conservation".
671:
Blunden, G; Campbell, S A; Smith, J R; Guiry, M D; Hession, C C; Griffin, R L (1997). "Chemical and physical characterization of calcified red algal deposits known as maërl".
731:
470:
Wilson, S., Blake, C., Berges, J.A., and Maggs, C.A. (2004) "Environmental tolerances of free-living coralline algae (maerl): implications for
European marine conservation".
109:
556:
262:
years has removed and degraded maerl beds. In
Cornwall, England, maerl has been extracted since the 1970s, but was banned in 2005 by Falmouth Harbour Commissioners.
250:. Maerl beds offer physical refuge and protection from predation as well as productive feeding grounds but are easily damaged by dredging and towed fishing gear.
341:
Blake, C.; Maggs, C.A. (2003). "Comparative growth rates and internal banding periodicity of maerl species (Corallinales, Rhodophyta) from northern Europe".
875:
Kamenos, N. A., Moore, P.G., Hall-Spencer, J.M. (2004b) Small-scale distribution of juvenile gadoids in shallow inshore waters; what role does maerl play?
269:
in 1690 who reported it from
Falmouth. In Ireland, maerl is extracted from subfossil beds in Bantry Bay by Celtic Sea Minerals. The maerl-forming species
1102:
596:
491:
417:
930:
541:
383:
Vize, S.; Blake, C.; Hinojosa, G. and Maggs, C.A. 2003. The distribution and composition of maerl beds in Northern Ireland.
397:
Lemoine (1910). "Répartition et mode de vie du maërl ( Lithothamnium calcareum) aux environs de Concarneau (Finistère)".
53:
1065:
894:
635:
580:
824:"Nursery-area function of maerl grounds for juvenile queen scallops Aequipecten opercularis and other invertebrates"
1193:
179:
Maerl fragments, Trá an Doilin, Maerl Beach (incorrectly known as "Coral Strand") Carraroe, County Galway, Ireland
202:
The ecology of maerl habitats has received very little attention in contrast to other marine ecosystems such as
306:
Steneck, R. S. (1986). "The Ecology of Coralline Algal Crusts: Convergent Patterns and Adaptative Strategies".
779:
Nelson, W (2009). "Calcified macroalgae – critical to coastal ecosystems and vulnerable to change: a review".
1078:
290:, and readily available alternative products (e.g., garden lime) make modern day exploitation controversial.
129:
Maerl is dredged from the sea floor and crushed to form a powder. It is still harvested around the coasts of
83:
is a sedimentological or genetic term for both the nodular and branched growth forms (Basso et al., 2015).
1128:"New Technological Interventions in Conservation Conflicts: Countering Emotions and Contested Knowledge"
456:
107:
growing loose in beds of fragmented nodules in the sub-littoral. The species generally involved are:
657:
246:
287:
115:
1188:
237:
945:
903:
880:
835:
506:
350:
165:
8:
810:
175:
977:
949:
907:
839:
755:
538:
533:
Grall, J. and Hall-Spencer, J.M. (2003) Problems facing maerl conservation in Brittany.
510:
475:
354:
319:
1160:
969:
688:
645:
366:
323:
150:
30:
1165:
1147:
1061:
631:
576:
228:
184:
146:
69:
1014:
973:
692:
370:
1155:
1139:
1010:
961:
953:
911:
853:
843:
788:
680:
623:
514:
432:
358:
315:
362:
168:, commissioned by Cornwall Council's Blue Natural Capital Project, found that the
1045:
915:
545:
169:
104:
72:
233:
1143:
706:
684:
627:
1182:
1151:
121:
100:
24:
1127:
1169:
519:
219:
172:
Estuary Special Area of Conservation supports an 880 hectare bed of maerl.
35:
203:
93:
965:
858:
848:
823:
732:"Giant ancient seaweed bed helping in the fight against climate change"
327:
138:
19:
457:
http://horizon.documentation.ird.fr/exl-doc/vcc/2006/11/010037649.pdf
437:
207:
75:
65:
957:
792:
492:"Scallop dredging has profound, long-term impacts on maerl habitats"
1027:
266:
242:
130:
46:
142:
224:
210:
beds. Maerl beds provide a complex habitat for a wide range of
134:
1126:
Verma, Audrey; van der Wal, René; Fischer, Anke (2017-10-01).
871:
869:
41:
616:
211:
866:
183:
Chemical analysis of maerl showed that it contained 32.1%
822:
Kamenos, N. A.; Moore, P.G.; Hall-Spencer, J.M. (2004a).
821:
670:
215:
881:
http://icesjms.oxfordjournals.org/content/61/3/422.short
756:"Cornwall researchers discover huge ancient seaweed bed"
164:
from 6–10 m. A 2024 survey by researchers from the
34:
Calcified remains of maerl, on the "coral beach" in the
1125:
57:
Pieces of popcorn-like maerl from Fuerteventura island.
1001:
Hall-Spencer, J.M. (2005). "Ban on maerl extraction".
938:
Aquatic Conservation: Marine and Freshwater Ecosystems
891:
811:
http://onlinelibrary.wiley.com/doi/10.1002/aqc.564/pdf
535:
Aquatic Conservation: Marine and Freshwater Ecosystems
425:
Aquatic Conservation: Marine and Freshwater Ecosystems
156:
Scientists investigated Falmouth maerl and found that
539:
http://www.ukmpas.org/pdf/Grall_Hall-Spencer_2003.pdf
476:
http://www.qub.ac.uk/bb-old/provan/pdf/charmaine2.pdf
277:
are listed in Annex V of the EC Habitats Directive.
453:Journal of Experimental Marine Biology and Ecology
928:
807:Aquatic Conservation: Marine Freshwater Ecosystem
489:
1180:
1060:Life Series. The Natural History Museum, London
931:"Problems facing maerl conservation in Brittany"
575:, Part 2B. The Natural History Museum, London.
466:
464:
418:"Monitoring deep Mediterranean rhodolith beds"
774:
772:
1000:
485:
483:
461:
885:
769:
664:
610:
340:
1159:
1079:"MMO ignores Cornwall dredge campaigners"
1050:
857:
847:
781:Journal of Marine and Freshwater Research
561:
518:
480:
436:
1076:
729:
567:Irvine, L.M and Chamberlain, Y.M. 1994.
308:Annual Review of Ecology and Systematics
265:An early reference to maerl was made by
253:Maerl has no tolerance for desiccation.
174:
52:
40:
29:
18:
396:
305:
1181:
929:Grall, J.; Hall-Spencer, J.M. (2003).
778:
490:Hall-Spencer, JM.; Moore, PG. (2000).
377:
103:maerl is composed of three species of
620:International Seaweed Symposium (XTH)
415:
399:Annales de l'Institut Océanographique
320:10.1146/annurev.es.17.110186.001421
13:
622:. Vol. 10. pp. 651–656.
472:Journal of Biological Conservation
160:predominated down to 6 m and
145:, and is a popular fertilizer for
14:
1205:
1119:
1095:
1070:
1032:
1021:
1015:10.1016/j.marpolbul.2005.01.013
994:
922:
815:
799:
748:
723:
699:
585:
550:
68:) is a collective name for non-
877:ICES Journal of Marine Science
828:Marine Ecology Progress Series
569:Seaweeds of the British Isles.
527:
499:ICES Journal of Marine Science
445:
409:
390:
334:
299:
86:
1:
730:Morrison, Alex (2024-03-04).
474:120, 279–289. Available at:
363:10.2216/i0031-8884-42-6-606.1
293:
916:10.1016/j.biocon.2004.03.001
879:61, 442–429. Available at:
153:, but this ceased in 2004.
7:
1028:Celtic Sea Minerals website
23:Maerl off the coast of the
10:
1210:
537:13, 55–64. Available at:
256:
197:
149:. It was also dredged off
110:Lithothamnion corallioides
1144:10.1007/s10745-017-9936-z
1003:Marine Pollution Bulletin
809:13, 5–20. Available at:
628:10.1515/9783110865271-088
455:338, 1–15 Available at:
271:Lithothamion corallioides
1194:Environment of Cornwall
1077:Divernet (2016-12-19).
895:Biological Conservation
685:10.1023/A:1007965325442
280:
275:Phymatolithon calcareum
247:Aequipecten opercularis
520:10.1006/jmsc.2000.0918
288:non-renewable resource
180:
116:Lithothamnion glaciale
58:
50:
38:
27:
238:Pollachius pollachius
178:
56:
44:
33:
22:
166:University of Exeter
950:2003ACMFE..13S..55G
908:2004BCons.120..279W
840:2004MEPS..274..183K
711:Let's Talk Cornwall
511:2000ICJMS..57.1407H
355:2003Phyco..42..606B
16:Coralline red algae
1044:2008-09-07 at the
849:10.3354/meps274183
673:J. Applied. Phycol
544:2015-06-17 at the
181:
151:Falmouth, Cornwall
59:
51:
39:
28:
1056:Thomas, D. 2002.
229:Pollachius virens
147:organic gardening
1201:
1174:
1173:
1163:
1123:
1117:
1116:
1114:
1113:
1107:OSPAR Commission
1099:
1093:
1092:
1090:
1089:
1074:
1068:
1054:
1048:
1036:
1030:
1025:
1019:
1018:
998:
992:
991:
989:
988:
982:
976:. Archived from
935:
926:
920:
919:
889:
883:
873:
864:
863:
861:
851:
819:
813:
803:
797:
796:
776:
767:
766:
764:
763:
752:
746:
745:
743:
742:
727:
721:
720:
718:
717:
703:
697:
696:
668:
662:
661:
655:
651:
649:
641:
614:
608:
607:
605:
604:
595:. Archived from
589:
583:
565:
559:
554:
548:
531:
525:
524:
522:
505:(5): 1407–1415.
496:
487:
478:
468:
459:
449:
443:
442:
440:
438:10.1002/aqc.2586
422:
413:
407:
406:
394:
388:
385:PMNHS Newsletter
381:
375:
374:
338:
332:
331:
303:
1209:
1208:
1204:
1203:
1202:
1200:
1199:
1198:
1179:
1178:
1177:
1124:
1120:
1111:
1109:
1101:
1100:
1096:
1087:
1085:
1075:
1071:
1055:
1051:
1046:Wayback Machine
1037:
1033:
1026:
1022:
999:
995:
986:
984:
980:
958:10.1002/aqc.568
933:
927:
923:
890:
886:
874:
867:
820:
816:
804:
800:
793:10.1071/MF08335
777:
770:
761:
759:
754:
753:
749:
740:
738:
728:
724:
715:
713:
705:
704:
700:
669:
665:
653:
652:
643:
642:
638:
615:
611:
602:
600:
591:
590:
586:
566:
562:
555:
551:
546:Wayback Machine
532:
528:
494:
488:
481:
469:
462:
450:
446:
420:
414:
410:
395:
391:
382:
378:
339:
335:
304:
300:
296:
283:
259:
200:
193:
188:
170:Fal and Helford
158:L. corallioides
105:coralline algae
89:
17:
12:
11:
5:
1207:
1197:
1196:
1191:
1176:
1175:
1138:(5): 683–695.
1118:
1094:
1069:
1049:
1031:
1020:
993:
921:
902:(2): 279–289.
884:
865:
814:
798:
787:(8): 187–801.
768:
747:
722:
698:
663:
654:|journal=
636:
609:
584:
560:
549:
526:
479:
460:
444:
431:(3): 549–561.
416:Basso (2015).
408:
389:
376:
349:(6): 606–612.
333:
297:
295:
292:
282:
279:
258:
255:
199:
196:
194:(dry weight).
191:
186:
88:
85:
15:
9:
6:
4:
3:
2:
1206:
1195:
1192:
1190:
1187:
1186:
1184:
1171:
1167:
1162:
1157:
1153:
1149:
1145:
1141:
1137:
1133:
1132:Human Ecology
1129:
1122:
1108:
1104:
1098:
1084:
1080:
1073:
1067:
1066:0-565-09175-1
1063:
1059:
1053:
1047:
1043:
1040:
1039:Forest Trends
1035:
1029:
1024:
1016:
1012:
1008:
1004:
997:
983:on 2015-06-17
979:
975:
971:
967:
963:
959:
955:
951:
947:
944:(S1): 55–64.
943:
939:
932:
925:
917:
913:
909:
905:
901:
897:
896:
888:
882:
878:
872:
870:
860:
855:
850:
845:
841:
837:
833:
829:
825:
818:
812:
808:
802:
794:
790:
786:
782:
775:
773:
757:
751:
737:
733:
726:
712:
708:
707:"Blue Carbon"
702:
694:
690:
686:
682:
678:
674:
667:
659:
647:
639:
637:9783110865271
633:
629:
625:
621:
613:
599:on 2021-12-04
598:
594:
588:
582:
581:0-11-310016-7
578:
574:
570:
564:
558:
553:
547:
543:
540:
536:
530:
521:
516:
512:
508:
504:
500:
493:
486:
484:
477:
473:
467:
465:
458:
454:
448:
439:
434:
430:
426:
419:
412:
404:
400:
393:
386:
380:
372:
368:
364:
360:
356:
352:
348:
344:
337:
329:
325:
321:
317:
313:
309:
302:
298:
291:
289:
278:
276:
272:
268:
263:
254:
251:
249:
248:
244:
241:and juvenile
240:
239:
235:
231:
230:
226:
222:
221:
217:
213:
209:
205:
195:
190:and 3.1% MgCO
189:
177:
173:
171:
167:
163:
159:
154:
152:
148:
144:
140:
136:
132:
127:
125:
123:
122:Phymatolithon
118:
117:
112:
111:
106:
102:
101:British Isles
97:
95:
84:
82:
77:
74:
71:
67:
63:
55:
48:
43:
37:
32:
26:
25:Isle of Arran
21:
1189:Corallinales
1135:
1131:
1121:
1110:. Retrieved
1106:
1103:"Maerl Beds"
1097:
1086:. Retrieved
1083:divernet.com
1082:
1072:
1057:
1052:
1034:
1023:
1006:
1002:
996:
985:. Retrieved
978:the original
966:10026.1/1359
941:
937:
924:
899:
893:
887:
876:
859:10026.1/1354
831:
827:
817:
806:
801:
784:
780:
760:. Retrieved
758:. 2024-03-02
750:
739:. Retrieved
735:
725:
714:. Retrieved
710:
701:
676:
672:
666:
619:
612:
601:. Retrieved
597:the original
587:
572:
568:
563:
552:
534:
529:
502:
498:
471:
452:
447:
428:
424:
411:
402:
398:
392:
384:
379:
346:
342:
336:
311:
307:
301:
284:
274:
270:
264:
260:
252:
245:
236:
227:
220:Gadus morhua
218:
204:kelp forests
201:
182:
162:P. calcareum
161:
157:
155:
128:
120:
114:
108:
98:
90:
80:
61:
60:
36:Isle of Skye
834:: 183–189.
593:"Algaebase"
314:: 273–303.
94:photic zone
87:Description
1183:Categories
1112:2024-03-07
1088:2024-03-07
1009:(2): 121.
987:2012-10-15
762:2024-03-07
741:2024-03-07
716:2024-03-07
603:2007-04-20
387:No.13 p.26
343:Phycologia
294:References
139:Bantry Bay
70:geniculate
1152:1572-9915
1058:Seaweeds.
679:: 11–17.
656:ignored (
646:cite book
557:Algaebase
208:sea grass
124:calcareum
81:rhodolith
76:red algae
73:coralline
66:rhodolith
45:Maerl in
1170:29170591
1042:Archived
974:53335266
693:43607799
542:Archived
371:83523566
267:John Ray
243:scallops
131:Brittany
47:Lanildut
1161:5680367
946:Bibcode
904:Bibcode
836:Bibcode
571:Volume
507:Bibcode
405:: 1–29.
351:Bibcode
328:2096997
257:History
234:Pollack
198:Ecology
143:Ireland
99:In the
1168:
1158:
1150:
1064:
972:
691:
634:
579:
369:
326:
225:saithe
135:France
64:(also
981:(PDF)
970:S2CID
934:(PDF)
689:S2CID
495:(PDF)
421:(PDF)
367:S2CID
324:JSTOR
62:Maerl
1166:PMID
1148:ISSN
1062:ISBN
736:News
658:help
632:ISBN
577:ISBN
281:Uses
273:and
212:taxa
185:CaCO
137:and
119:and
1156:PMC
1140:doi
1011:doi
962:hdl
954:doi
912:doi
900:120
854:hdl
844:doi
832:274
789:doi
681:doi
624:doi
515:doi
433:doi
359:doi
316:doi
216:cod
206:or
133:in
1185::
1164:.
1154:.
1146:.
1136:45
1134:.
1130:.
1105:.
1081:.
1007:50
1005:.
968:.
960:.
952:.
942:13
940:.
936:.
910:.
898:.
868:^
852:.
842:.
830:.
826:.
785:60
783:.
771:^
734:.
709:.
687:.
675:.
650::
648:}}
644:{{
630:.
513:.
503:57
501:.
497:.
482:^
463:^
429:26
427:.
423:.
401:.
365:.
357:.
347:42
345:.
322:.
312:17
310:.
232:,
223:,
141:,
126:.
113:,
1172:.
1142::
1115:.
1091:.
1017:.
1013::
990:.
964::
956::
948::
918:.
914::
906::
862:.
856::
846::
838::
795:.
791::
765:.
744:.
719:.
695:.
683::
677:9
660:)
640:.
626::
606:.
573:1
523:.
517::
509::
441:.
435::
403:1
373:.
361::
353::
330:.
318::
192:3
187:3
49:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
_on_human_hand.jpg)
