ASSESSMENT OF SALINITY-RELATED MORTALITY OF FRESH-WATER BACTERIA IN THE SAINT-LAWRENCE ESTUARY

被引:34
作者
PAINCHAUD, J [1 ]
THERRIAULT, JC [1 ]
LEGENDRE, L [1 ]
机构
[1] MINIST PECHES & OCEANS,INST MAURICE LAMONTAGNE,MONT JOLI,PQ G5H 3Z4,CANADA
关键词
D O I
10.1128/AEM.61.1.205-208.1995
中图分类号
Q81 [生物工程学(生物技术)]; Q93 [微生物学];
学科分类号
071005 ; 0836 ; 090102 ; 100705 ;
摘要
The growth response of freshwater bacteria from the St. Lawrence River, exposed to brackish waters (salinity of 0 to 20%) from the upper estuary, was assessed by a methodology requiring the combined use of dilution cultures and diffusion chambers. The longitudinal distribution of bacterial abundance in waters within this salinity range was also examined. Growth of the freshwater bacteria was reduced by 15 and 50% after exposure to salinities of 10 and 20%, respectively. At lower salinities, no growth reduction was observed, and at a salinity of 2%, growth was even stimulated. Longitudinal distribution data showed that bacterial abundance also peaked at this salinity. In contrast with an earlier hypothesis, this study shows that the decline of bacterial abundance in the low-salinity waters of the estuary is not caused by salinity-related mortality of freshwater bacteria, because the mixing time between fresh and marine (>20%) waters is relatively long (days). However, results suggest that mortality of freshwater bacteria can be an important process in estuaries with shorter mixing times (hours). The combined use of diffusion chambers and dilution cultures proved to be a valuable methodology for assessing growth (or mortality) of bacteria exposed to environmental gradients.
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收藏
页码:205 / 208
页数:4
相关论文
共 28 条
[11]   ESTIMATING THE GRAZING IMPACT OF MARINE MICRO-ZOOPLANKTON [J].
LANDRY, MR ;
HASSETT, RP .
MARINE BIOLOGY, 1982, 67 (03) :283-288
[12]   SURVIVAL OF NATURAL SEWAGE POPULATIONS OF ENTERIC BACTERIA IN DIFFUSION AND BATCH CHAMBERS IN THE MARINE-ENVIRONMENT [J].
LESSARD, EJ ;
SIEBURTH, JM .
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 1983, 45 (03) :950-959
[13]   GROWTH OF BACTERIA IN SEAWATER FILTERED THROUGH 0.2 MU-M NUCLEPORE MEMBRANES - IMPLICATIONS FOR DILUTION EXPERIMENTS [J].
LI, WKW ;
DICKIE, PM .
MARINE ECOLOGY PROGRESS SERIES, 1985, 26 (03) :245-252
[15]   MICROBIAL GRADIENTS IN A TURBID ESTUARY - APPLICATION OF A NEW METHOD FOR PROTOZOAN COMMUNITY ANALYSIS [J].
LOVEJOY, C ;
VINCENT, WF ;
FRENETTE, JJ ;
DODSON, JJ .
LIMNOLOGY AND OCEANOGRAPHY, 1993, 38 (06) :1295-1303
[16]   ESTUARINE CHEMISTRY - ORGANIC FILMS AT THE HALOCLINE [J].
MANTOURA, RFC .
NATURE, 1987, 328 (6131) :579-580
[17]   SURVIVAL OF COLIFORM BACTERIA IN NATURAL WATERS - FIELD AND LABORATORY STUDIES WITH MEMBRANE-FILTER CHAMBERS [J].
MCFETERS, GA ;
STUART, DG .
APPLIED MICROBIOLOGY, 1972, 24 (05) :805-811
[18]   VERY LOW SALINITY REGIONS OF ESTUARIES - IMPORTANT SITES FOR CHEMICAL AND BIOLOGICAL REACTIONS [J].
MORRIS, AW ;
MANTOURA, RFC ;
BALE, AJ ;
HOWLAND, RJM .
NATURE, 1978, 274 (5672) :678-680
[19]   RELATIONSHIPS BETWEEN BACTERIA, PHYTOPLANKTON AND PARTICULATE ORGANIC-CARBON IN THE UPPER ST-LAWRENCE ESTUARY [J].
PAINCHAUD, J ;
THERRIAULT, JC .
MARINE ECOLOGY PROGRESS SERIES, 1989, 56 (03) :301-311
[20]   BOX MODEL ANALYSIS OF BACTERIAL FLUXES IN THE ST-LAWRENCE ESTUARY [J].
PAINCHAUD, J ;
LEFAIVRE, D ;
THERRIAULT, JC .
MARINE ECOLOGY PROGRESS SERIES, 1987, 41 (03) :241-252