ISSN:
1573-5052
Keywords:
Submerged macrophytes
;
Salinity
;
Biomass production
;
Sediment organic matter
;
Nitrogen
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Nomenclature: follows Flora Europea (Tutin et al. 1964–1980). Since the extension of the irrigation system, the water regime of most of the permanent marshes of the Camargue (southern France) have been intensively controlled. Considerable quantities of nutrient rich Rhone water are pumped into these marshes, leading to lower salinities and a higher biomass production and consequently an increasing organic matter concentration of the sediments. Myriophyllum spicatum has become abundant in these permanent marshes since large quantities of freshwater entered these systems. It has displaced Potamogeton pectinatus in several of these marshes. The different factors likely to influence the distribution of P. pectinatus and M. spicatum were investigated experimentally. The impact of Cl- concentrations between 0 and 6 g l-1 on the biomass production of both species was tested. P. pectinatus appears to be more salt tolerant than M. spicatum. The influence of sediment quality on the biomass production of both species was investigated using six sediments differing in organic matter concentration. Compared to P. pectinatus, M. spicatum had a lower total biomass production when grown on sediments with low organic matter concentration (2–4% organic matter) and a higher biomass production on sediments with relatively high organic matter concentration (9–13% organic matter). Nitrogen addition to the sediments yielded an increased biomass production of P. pectinatus and M. spicatum. On some sediments M. spicatum needed higher concentrations of nitrogen than P. pectinatus to increase its biomass production. The creation of freshwater marshes by the introduction of irrigation water, resulting in lower salinities and an increase in sediment organic matter concentration, stimulates the biomass production of M. spicatum. As M. spicatum grows less well on poor sediments and at higher salinities it seems to be unable to displace P. pectinatus in more natural systems in the Camargue.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00044233
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