80:
Originally, it was thought that ecosystems increase uniformly in ascendency as they developed, but subsequent empirical observation has suggested that all sustainable ecosystems are confined to a narrow "window of vitality" (Ulanowicz 2002). Systems with relative values of ascendency plotting below
65:(1922) had suggested that a system's capacity to prevail in evolution was related to its ability to capture useful power. Ascendency can thus be regarded as a refinement of Lotka's supposition that also takes into account how power is actually being channeled within a system.
60:
One way of depicting ascendency is to regard it as "organized power", because the index represents the magnitude of the power that is flowing within the system towards particular ends, as distinct from power that is dissipated naturally. Almost half a century earlier,
68:
In mathematical terms, ascendency is the product of the aggregate amount of material or energy being transferred in an ecosystem times the coherency with which the outputs from the members of the system relate to the set of inputs to the same components
81:
the window tend to fall apart due to lack of significant internal constraints, whereas systems above the window tend to be so "brittle" that they become vulnerable to external perturbations.
88:(Ulanowicz and Baird 1999). That is, ascendency can be used to identify which resource is limiting the functioning of each component of the ecosystem.
1065:
318:
91:
It is thought that autocatalytic feedback is the primary route by which systems increase and maintain their ascendencies (Ulanowicz 1997.)
1209:
1279:
851:
816:
163:
Rutledge, Robert W.; Basore, Bennett L.; Mulholland, Robert J. (1976). "Ecological stability: An information theory viewpoint".
1289:
1017:
84:
Sensitivity analysis on the components of the ascendency reveals the controlling transfers within the system in the sense of
259:
Ulanowicz, Robert E.; Baird, Daniel (1999). "Nutrient controls on ecosystem dynamics: the
Chesapeake mesohaline community".
1294:
1482:
1235:
1058:
899:
311:
571:
1875:
1032:
1314:
1027:
894:
606:
1699:
1572:
1745:
1344:
1299:
1051:
304:
831:
1177:
1870:
1534:
425:
28:
1599:
1319:
806:
523:
420:
207:
Ulanowicz, R.E. 1986. Growth & Development: Ecosystems
Phenomenology. Springer-Verlag, NY. 203 p.
74:
1780:
1392:
1284:
1142:
1127:
1122:
801:
513:
296:
1880:
1770:
1765:
1735:
1539:
1002:
884:
17:
1043:
674:
1614:
1477:
1387:
1255:
1137:
1107:
964:
929:
649:
616:
591:
210:
Ulanowicz, R.E. 1997. Ecology, the
Ascendent Perspective. Columbia University Press, NY. 201p.
1760:
1704:
1639:
1502:
1437:
1372:
934:
722:
430:
410:
53:. It is intended to capture in a single index the ability of an ecosystem to prevail against
1664:
1609:
1472:
1457:
1240:
1197:
1187:
1182:
939:
919:
775:
765:
707:
702:
538:
390:
54:
1790:
1755:
1750:
1674:
1669:
1624:
1522:
1492:
1487:
1339:
1202:
1192:
737:
576:
365:
268:
223:
172:
115:
8:
1840:
1815:
1679:
1649:
1594:
1507:
1397:
1382:
1329:
1162:
1097:
979:
909:
841:
440:
272:
227:
176:
119:
1851:
1800:
1795:
1604:
1567:
1309:
1265:
1230:
1087:
1012:
914:
846:
836:
770:
717:
528:
473:
435:
360:
146:
103:
50:
280:
235:
1740:
1709:
1497:
1324:
1132:
997:
974:
712:
488:
400:
385:
370:
350:
284:
247:
239:
196:
188:
184:
151:
133:
85:
1694:
1557:
1549:
1467:
1349:
1334:
1270:
1250:
1167:
1157:
1152:
1117:
949:
889:
760:
561:
503:
415:
375:
276:
231:
180:
141:
123:
70:
1830:
1689:
1659:
1654:
1644:
1577:
1562:
1442:
1422:
1304:
1172:
1078:
969:
879:
821:
405:
331:
62:
46:
214:
Ulanowicz, Robert E. (2002). "The balance between adaptability and adaptation".
1810:
1634:
1587:
1517:
1512:
1407:
1274:
1147:
954:
944:
924:
727:
692:
631:
508:
463:
355:
1864:
1835:
811:
785:
742:
732:
687:
654:
546:
380:
335:
288:
243:
192:
137:
1820:
1805:
1462:
1432:
1377:
1260:
1225:
1102:
601:
251:
155:
1112:
659:
621:
596:
586:
551:
498:
478:
200:
128:
1825:
1402:
1367:
1007:
959:
904:
780:
697:
641:
518:
468:
1730:
1684:
1412:
856:
826:
626:
581:
556:
493:
483:
458:
450:
395:
326:
42:
1785:
1714:
1245:
1073:
752:
664:
611:
566:
1775:
1582:
1452:
1447:
1074:
1022:
682:
327:
77:
shared between inputs and outputs (Rutledge et al. 1976).
162:
49:. Ascendency is derived using mathematical tools from
57:by virtue of its combined organization and size.
1862:
108:Proceedings of the National Academy of Sciences
258:
1059:
312:
104:"Contribution to the Energetics of Evolution"
45:, defined as a function of the ecosystem's
1280:Latitudinal gradients in species diversity
1066:
1052:
319:
305:
213:
145:
127:
1178:Predator–prey (Lotka–Volterra) equations
817:Tritrophic interactions in plant defense
1210:Random generalized Lotka–Volterra model
14:
1863:
1018:Herbivore adaptations to plant defense
1047:
300:
101:
1033:Predator avoidance in schooling fish
1483:Intermediate disturbance hypothesis
73:1986). Coherence is gauged by the
24:
1236:Ecological effects of biodiversity
41:is a quantitative attribute of an
25:
1892:
572:Generalist and specialist species
1295:Occupancy–abundance relationship
1315:Relative abundance distribution
1028:Plant defense against herbivory
895:Competitive exclusion principle
607:Mesopredator release hypothesis
900:Consumer–resource interactions
165:Journal of Theoretical Biology
13:
1:
1746:Biological data visualization
1573:Environmental niche modelling
1300:Population viability analysis
281:10.1016/s0924-7963(98)90017-3
267:(1–3). Elsevier BV: 159–172.
236:10.1016/s0303-2647(01)00170-8
94:
1231:Density-dependent inhibition
185:10.1016/0022-5193(76)90007-2
7:
1700:Liebig's law of the minimum
1535:Resource selection function
426:Metabolic theory of ecology
222:(1–3). Elsevier BV: 13–22.
171:(2). Elsevier BV: 355–371.
102:Lotka, A. J. (1922-06-01).
10:
1897:
1600:Niche apportionment models
1320:Relative species abundance
524:Primary nutritional groups
421:List of feeding behaviours
75:average mutual information
26:
1849:
1781:Ecosystem based fisheries
1723:
1623:
1548:
1421:
1393:Interspecific competition
1358:
1285:Minimum viable population
1218:
1143:Maximum sustainable yield
1128:Intraspecific competition
1123:Effective population size
1086:
1003:Anti-predator adaptations
988:
867:
794:
751:
673:
640:
537:
514:Photosynthetic efficiency
449:
343:
261:Journal of Marine Systems
1771:Ecological stoichiometry
1736:Alternative stable state
27:Not to be confused with
1876:Entropy and information
1615:Ontogenetic niche shift
1478:Ideal free distribution
1388:Ecological facilitation
1138:Malthusian growth model
1108:Consumer-resource model
965:Paradox of the plankton
930:Energy systems language
650:Chemoorganoheterotrophy
617:Optimal foraging theory
592:Heterotrophic nutrition
1761:Ecological forecasting
1705:Marginal value theorem
1503:Landscape epidemiology
1438:Cross-boundary subsidy
1373:Biological interaction
723:Microbial intelligence
411:Green world hypothesis
1766:Ecological humanities
1665:Ecological energetics
1610:Niche differentiation
1473:Habitat fragmentation
1241:Ecological extinction
1188:Small population size
940:Feed conversion ratio
920:Ecological succession
852:San Francisco Estuary
766:Ecological efficiency
708:Microbial cooperation
1791:Evolutionary ecology
1756:Ecological footprint
1751:Ecological economics
1675:Ecological threshold
1670:Ecological indicator
1540:Source–sink dynamics
1493:Land change modeling
1488:Insular biogeography
1340:Species distribution
1079:Modelling ecosystems
738:Microbial metabolism
577:Intraguild predation
366:Biogeochemical cycle
332:Modelling ecosystems
129:10.1073/pnas.8.6.147
1841:Theoretical ecology
1816:Natural environment
1680:Ecosystem diversity
1650:Ecological collapse
1640:Bateman's principle
1595:Limiting similarity
1508:Landscape limnology
1330:Species homogeneity
1168:Population modeling
1163:Population dynamics
980:Trophic state index
273:1999JMS....19..159U
228:2002BiSys..64...13U
177:1976JThBi..57..355R
120:1922PNAS....8..147L
1871:Information theory
1852:Outline of ecology
1801:Industrial ecology
1796:Functional ecology
1660:Ecological deficit
1605:Niche construction
1568:Ecosystem engineer
1345:Species–area curve
1266:Introduced species
1081:: Other components
1013:Deimatic behaviour
915:Ecological network
847:North Pacific Gyre
832:hydrothermal vents
771:Ecological pyramid
718:Microbial food web
529:Primary production
474:Foundation species
51:information theory
1858:
1857:
1741:Balance of nature
1498:Landscape ecology
1383:Community ecology
1325:Species diversity
1261:Indicator species
1256:Gradient analysis
1133:Logistic function
1041:
1040:
998:Animal coloration
975:Trophic mutualism
713:Microbial ecology
504:Photoheterotrophs
489:Myco-heterotrophy
401:Ecosystem ecology
386:Carrying capacity
351:Abiotic component
16:(Redirected from
1888:
1558:Ecological niche
1530:selection theory
1350:Umbrella species
1335:Species richness
1271:Invasive species
1251:Flagship species
1158:Population cycle
1153:Overexploitation
1118:Ecological yield
1068:
1061:
1054:
1045:
1044:
950:Mesotrophic soil
890:Climax community
822:Marine food webs
761:Biomagnification
562:Chemoorganotroph
416:Keystone species
376:Biotic component
321:
314:
307:
298:
297:
292:
255:
204:
159:
149:
131:
21:
1896:
1895:
1891:
1890:
1889:
1887:
1886:
1885:
1881:Trophic ecology
1861:
1860:
1859:
1854:
1845:
1831:Systems ecology
1719:
1690:Extinction debt
1655:Ecological debt
1645:Bioluminescence
1626:
1619:
1588:marine habitats
1563:Ecological trap
1544:
1424:
1417:
1360:
1354:
1310:Rapoport's rule
1305:Priority effect
1246:Endemic species
1214:
1173:Population size
1089:
1082:
1072:
1042:
1037:
990:
984:
970:Trophic cascade
880:Bioaccumulation
863:
790:
747:
669:
636:
533:
445:
406:Ecosystem model
339:
325:
295:
97:
63:Alfred J. Lotka
47:trophic network
32:
23:
22:
15:
12:
11:
5:
1894:
1884:
1883:
1878:
1873:
1856:
1855:
1850:
1847:
1846:
1844:
1843:
1838:
1833:
1828:
1823:
1818:
1813:
1811:Microecosystem
1808:
1803:
1798:
1793:
1788:
1783:
1778:
1773:
1768:
1763:
1758:
1753:
1748:
1743:
1738:
1733:
1727:
1725:
1721:
1720:
1718:
1717:
1712:
1710:Thorson's rule
1707:
1702:
1697:
1692:
1687:
1682:
1677:
1672:
1667:
1662:
1657:
1652:
1647:
1642:
1637:
1635:Assembly rules
1631:
1629:
1621:
1620:
1618:
1617:
1612:
1607:
1602:
1597:
1592:
1591:
1590:
1580:
1575:
1570:
1565:
1560:
1554:
1552:
1546:
1545:
1543:
1542:
1537:
1532:
1520:
1518:Patch dynamics
1515:
1513:Metapopulation
1510:
1505:
1500:
1495:
1490:
1485:
1480:
1475:
1470:
1465:
1460:
1455:
1450:
1445:
1440:
1435:
1429:
1427:
1419:
1418:
1416:
1415:
1410:
1408:Storage effect
1405:
1400:
1395:
1390:
1385:
1380:
1375:
1370:
1364:
1362:
1356:
1355:
1353:
1352:
1347:
1342:
1337:
1332:
1327:
1322:
1317:
1312:
1307:
1302:
1297:
1292:
1290:Neutral theory
1287:
1282:
1277:
1275:Native species
1268:
1263:
1258:
1253:
1248:
1243:
1238:
1233:
1228:
1222:
1220:
1216:
1215:
1213:
1212:
1207:
1206:
1205:
1200:
1190:
1185:
1180:
1175:
1170:
1165:
1160:
1155:
1150:
1148:Overpopulation
1145:
1140:
1135:
1130:
1125:
1120:
1115:
1110:
1105:
1100:
1094:
1092:
1084:
1083:
1071:
1070:
1063:
1056:
1048:
1039:
1038:
1036:
1035:
1030:
1025:
1020:
1015:
1010:
1005:
1000:
994:
992:
986:
985:
983:
982:
977:
972:
967:
962:
957:
955:Nutrient cycle
952:
947:
945:Feeding frenzy
942:
937:
932:
927:
925:Energy quality
922:
917:
912:
907:
902:
897:
892:
887:
885:Cascade effect
882:
877:
871:
869:
865:
864:
862:
861:
860:
859:
854:
849:
844:
839:
834:
829:
819:
814:
809:
804:
798:
796:
792:
791:
789:
788:
783:
778:
773:
768:
763:
757:
755:
749:
748:
746:
745:
740:
735:
730:
728:Microbial loop
725:
720:
715:
710:
705:
700:
695:
693:Lithoautotroph
690:
685:
679:
677:
675:Microorganisms
671:
670:
668:
667:
662:
657:
652:
646:
644:
638:
637:
635:
634:
632:Prey switching
629:
624:
619:
614:
609:
604:
599:
594:
589:
584:
579:
574:
569:
564:
559:
554:
549:
543:
541:
535:
534:
532:
531:
526:
521:
516:
511:
509:Photosynthesis
506:
501:
496:
491:
486:
481:
476:
471:
466:
464:Chemosynthesis
461:
455:
453:
447:
446:
444:
443:
438:
433:
428:
423:
418:
413:
408:
403:
398:
393:
388:
383:
378:
373:
368:
363:
358:
356:Abiotic stress
353:
347:
345:
341:
340:
324:
323:
316:
309:
301:
294:
293:
256:
211:
208:
205:
160:
114:(6): 147–151.
98:
96:
93:
9:
6:
4:
3:
2:
1893:
1882:
1879:
1877:
1874:
1872:
1869:
1868:
1866:
1853:
1848:
1842:
1839:
1837:
1836:Urban ecology
1834:
1832:
1829:
1827:
1824:
1822:
1819:
1817:
1814:
1812:
1809:
1807:
1804:
1802:
1799:
1797:
1794:
1792:
1789:
1787:
1784:
1782:
1779:
1777:
1774:
1772:
1769:
1767:
1764:
1762:
1759:
1757:
1754:
1752:
1749:
1747:
1744:
1742:
1739:
1737:
1734:
1732:
1729:
1728:
1726:
1722:
1716:
1713:
1711:
1708:
1706:
1703:
1701:
1698:
1696:
1695:Kleiber's law
1693:
1691:
1688:
1686:
1683:
1681:
1678:
1676:
1673:
1671:
1668:
1666:
1663:
1661:
1658:
1656:
1653:
1651:
1648:
1646:
1643:
1641:
1638:
1636:
1633:
1632:
1630:
1628:
1622:
1616:
1613:
1611:
1608:
1606:
1603:
1601:
1598:
1596:
1593:
1589:
1586:
1585:
1584:
1581:
1579:
1576:
1574:
1571:
1569:
1566:
1564:
1561:
1559:
1556:
1555:
1553:
1551:
1547:
1541:
1538:
1536:
1533:
1531:
1529:
1525:
1521:
1519:
1516:
1514:
1511:
1509:
1506:
1504:
1501:
1499:
1496:
1494:
1491:
1489:
1486:
1484:
1481:
1479:
1476:
1474:
1471:
1469:
1468:Foster's rule
1466:
1464:
1461:
1459:
1456:
1454:
1451:
1449:
1446:
1444:
1441:
1439:
1436:
1434:
1431:
1430:
1428:
1426:
1420:
1414:
1411:
1409:
1406:
1404:
1401:
1399:
1396:
1394:
1391:
1389:
1386:
1384:
1381:
1379:
1376:
1374:
1371:
1369:
1366:
1365:
1363:
1357:
1351:
1348:
1346:
1343:
1341:
1338:
1336:
1333:
1331:
1328:
1326:
1323:
1321:
1318:
1316:
1313:
1311:
1308:
1306:
1303:
1301:
1298:
1296:
1293:
1291:
1288:
1286:
1283:
1281:
1278:
1276:
1272:
1269:
1267:
1264:
1262:
1259:
1257:
1254:
1252:
1249:
1247:
1244:
1242:
1239:
1237:
1234:
1232:
1229:
1227:
1224:
1223:
1221:
1217:
1211:
1208:
1204:
1201:
1199:
1196:
1195:
1194:
1191:
1189:
1186:
1184:
1181:
1179:
1176:
1174:
1171:
1169:
1166:
1164:
1161:
1159:
1156:
1154:
1151:
1149:
1146:
1144:
1141:
1139:
1136:
1134:
1131:
1129:
1126:
1124:
1121:
1119:
1116:
1114:
1111:
1109:
1106:
1104:
1101:
1099:
1096:
1095:
1093:
1091:
1085:
1080:
1076:
1069:
1064:
1062:
1057:
1055:
1050:
1049:
1046:
1034:
1031:
1029:
1026:
1024:
1021:
1019:
1016:
1014:
1011:
1009:
1006:
1004:
1001:
999:
996:
995:
993:
987:
981:
978:
976:
973:
971:
968:
966:
963:
961:
958:
956:
953:
951:
948:
946:
943:
941:
938:
936:
933:
931:
928:
926:
923:
921:
918:
916:
913:
911:
908:
906:
903:
901:
898:
896:
893:
891:
888:
886:
883:
881:
878:
876:
873:
872:
870:
866:
858:
855:
853:
850:
848:
845:
843:
840:
838:
835:
833:
830:
828:
825:
824:
823:
820:
818:
815:
813:
810:
808:
805:
803:
800:
799:
797:
793:
787:
786:Trophic level
784:
782:
779:
777:
774:
772:
769:
767:
764:
762:
759:
758:
756:
754:
750:
744:
743:Phage ecology
741:
739:
736:
734:
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1821:Regime shift
1806:Macroecology
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1463:Edge effects
1433:Biogeography
1378:Commensalism
1226:Biodiversity
1103:Allee effect
874:
842:kelp forests
795:Example webs
660:Detritivores
499:Organotrophs
479:Kinetotrophs
431:Productivity
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1458:Disturbance
1361:interaction
1183:Recruitment
1113:Depensation
905:Copiotrophs
776:Energy flow
698:Lithotrophy
642:Decomposers
622:Planktivore
597:Insectivore
587:Heterotroph
552:Bacterivore
519:Phototrophs
469:Chemotrophs
441:Restoration
391:Competition
55:disturbance
1865:Categories
1826:Sexecology
1403:Parasitism
1368:Antibiosis
1203:Resistance
1198:Resilience
1088:Population
1008:Camouflage
960:Oligotroph
875:Ascendency
837:intertidal
827:cold seeps
781:Food chain
582:Herbivores
557:Carnivores
484:Mixotrophs
459:Autotrophs
338:components
216:Biosystems
95:References
39:ascendancy
35:Ascendency
29:Ascendancy
1731:Allometry
1685:Emergence
1413:Symbiosis
1398:Mutualism
1193:Stability
1098:Abundance
910:Dominance
868:Processes
857:tide pool
753:Food webs
627:Predation
612:Omnivores
539:Consumers
494:Mycotroph
451:Producers
396:Ecosystem
361:Behaviour
289:0924-7963
244:0303-2647
193:0022-5193
138:0027-8424
71:Ulanowicz
43:ecosystem
1786:Endolith
1715:Xerosere
1627:networks
1443:Ecocline
989:Defense,
665:Detritus
567:Foraging
436:Resource
252:11755484
156:16576642
18:Ascended
1776:Ecopath
1583:Habitat
1453:Ecotype
1448:Ecotone
1425:ecology
1423:Spatial
1359:Species
1219:Species
1090:ecology
1075:Ecology
1023:Mimicry
991:counter
935:f-ratio
683:Archaea
371:Biomass
344:General
336:Trophic
328:Ecology
269:Bibcode
224:Bibcode
173:Bibcode
147:1085052
116:Bibcode
807:Rivers
703:Marine
287:
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201:957665
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86:Liebig
1724:Other
1625:Other
1578:Guild
1550:Niche
802:Lakes
812:Soil
285:ISSN
248:PMID
240:ISSN
197:PMID
189:ISSN
152:PMID
134:ISSN
277:doi
232:doi
181:doi
142:PMC
124:doi
37:or
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