Macroinfaunal assemblages associated with mussel and clam beds in an estuary of Southern Chile

Samples were collected from September 1990 to February 1992, at three subtidal sites of the middle reaches of the Queule River estuary, southern Chile, to analyze the spatial and temporal variability of the macroinfauna inhabiting substrata with different abundances of bivalves. In addition, water and sediment samples were obtained to study the relationships between the temporal variability in macroinfaunal abundances, physical factors, and chlorophyll a content. Temperature, salinity, and chlorophyll a showed a rather strong seasonal variability but slight between-site differences. Sediment characteristics and bivalve abundances, by contrast, exhibited little temporal variability but large differences between sites. The macroinfauna was primarily represented by polychaetes, Prionospio (Minuspio) patagonica being dominant in the three areas. Most dominant species showed similar trends of temporal variability, with maximum abundances recorded during spring and fall. The appearance of recruits was restricted to the summer with little difference among sites. Multiple regression analyses showed that the temporal variability of macroinfaunal adults and recruits, was primarily associated with variability in salinity and water temperature, respectively. Spatial variability of these organisms was also explained by variations in these factors, together with those of sediment texture and organic matter content. No evidence of interactions (significant relationships) was found between the abundances of bivalves and those of the macroinfauna, nor among macroinfaunal organisms.PT: J; CR: ANDERSSON CA, 1981, ADV CERAM, V3, P184 ANDRE C, 1991, MAR ECOL-PROG SER, V71, P227 BACHELET G, 1986, HYDROBIOLOGIA, V142, P233 BERTRAN CE, 1989, REV CHIL HIST NAT, V62, P19 BEUKEMA JJ, 1986, OPHELIA, V26, P45 BEUKEMA JJ, 1990, EXPECTED EFFECTS CLI, P83 BRAVO A, 1989, THESIS U AUSTR CHILE BUTMAN CA, 1987, OCEANOGR MAR BIOL, V25, P113 DETHIER MN, 1984, ECOL MONOGR, V54, P99 DEVOOYS CGN, 1990, EXPECTED EFFECTS CLI, P83 DITTMANN S, 1990, HELGOLANDER MEERESUN, V44, P335 FOLK RL, 1980, PETROLOGY SEDIMENTAR GRASSLE JF, 1974, J MARINE RE, V32, P253 GRAY JS, 1974, OCEANOGR MAR BIOL AN, V12, P223 HAIR JF, 1979, MULTIVARIATE ANAL HAVEN DS, 1972, GEOL SOC AM MEM, V133, P121 HINES AH, 1989, VELIGER, V32, P109 HOLLAND AF, 1987, ESTUARIES, V10, P227 JARAMILLO E, 1985, STUDIES NEOTROPICAL, V20, P33 JARAMILLO E, 1992, PSZNI MAR ECOL, V13, P317 JARAMILLO E, 1993, MARINE ECOLOGY PROGR, V82, P85 JOHNSON RG, 1977, J MAR RES, V35, P273 LEVIN LA, 1984, ECOLOGY, V65, P1185 LOW A, 1993, THESIS U AUSTR CHILE NICHOLS FH, 1986, SCIENCE, V231, P525 OLAFSSON EB, 1986, J ANIM ECOL, V55, P517 PATERSON DM, 1991, DEV COASTAL ENG, P111 PETERSON CH, 1979, ECOLOGICAL PROCESSES, P233 PETERSON CH, 1987, LIMNOL OCEANOGR, V32, P143 PETHICK J, 1984, INTRO COASTAL GEOMOR PINO M, 1983, REV GEOLOGICA CHILE, V18, P77 POSEY MH, 1987, MAR ECOL-PROG SER, V39, P99 POSEY MH, 1990, REV AQUAT SCI, V2, P343 QUIJON P, 1993, ESTUAR COAST SHELF S, V37, P655 REISE K, 1983, MAR ECOL-PROG SER, V12, P229 REISE K, 1985, TIDAL FLAT ECOLOGY E RHOADS DC, 1970, J MAR RES, V28, P150 RHOADS DC, 1982, ANIMAL SEDIMENT RELA, P3 RISK MJ, 1977, J SEDIMENT PETROL, V47, P1425 ROJAS C, 1984, REV BIOL MARINA VALP, V20, P139 ROMAN MR, 1978, ESTUARINE COASTAL MA, V6, P47 SHA LP, 1991, CLASTIC TIDAL SEDIME, P199 SOKAL RR, 1969, BIOMETRIA SOUZA WP, 1979, ECOLOGY, V60, P1225 STOLINE MR, 1981, AM STAT, V35, P134 STRICKLAND JDH, 1972, B FISH RES BOARD CAN, V167 THISTLE D, 1981, MAR ECOL-PROG SER, V6, P223 TORO JE, 1984, REV BIOL MARINA VALP, V20, P23 VOS PC, 1988, TIDE INFLUENCED SEDI, P511 WILSON WH, 1991, ANNU REV ECOL SYST, V21, P221 WOODIN SA, 1976, J MARKETING RES, V34, P25; NR: 51; TC: 8; J9: ESTUARIES; PG: 13; GA: TU217Source type: Electronic(1