The effect of salinity on the dominance‐diversity relations of experimental coastal macrophyte communities

Grillas, Patrick; Wijck, Carla van; Bonis, Anne

doi:10.2307/3236072

Cited by 26 publications

(18 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Salinity and flooding period have been recognized as the main factors determining the composition and zonation of submerged macrophytes in Mediterranean wetlands (Grillas 1990;Grillas et al 1993;Espinar et al 2002). The distribution of aquatic macrophytes following the observed proportion of the two main cations supports the view suggested by Brock (1986) that it is the adaptation to wide fluctuations of combined environmental factors rather than extreme levels of each factor that may determine the floral composition in saline and temporary water bodies.…”

Section: Discussionmentioning

confidence: 83%

A quantitative hydrogeomorphic approach to the classification of temporary wetlands in the Doñana National Park (SW Spain)

Espinar

Serrano

2008

Aquat Ecol

View full text Add to dashboard Cite

A quantitative hydrogeomorphic approach was applied to an extensive survey of temporary wetlands in the Doñana National Park (SW Spain) in search for quantitative thresholds for wetland classification. Twenty freshwater ponds on the aeolian sand mantle and 46 sites on silty-clay substrate, located in the southern marshland, were surveyed during the heaviest rainy period so far recorded (October 1995-September 1997. On average, temporary ponds showed higher water depth, longer flooding period, lower conductivity (\0.5 mS cm -1 ), lower pH (6.7), lower phosphate concentration (0.4 lM) and a more balanced proportion of Ca 2+ /Na + than temporary marshes. During floods, marshland sites exhibited higher water transparency, pH (9.5), alkalinity (3.5 meq l -1 ), conductivity (8.2 mS cm -1 ), phosphate concentration (0.7 lM), Na + and Ca 2+ concentrations (97.2 and 3.5 meq l -1 , respectively) than ponds. Study sites were significantly segregated (ANOSIM test: R = 0.88, P \ 0.01, n = 92) in relation to water depth and conductivity. A conductivity of 1.6 mS cm -1 is proposed as a threshold between marshland sites and ponds during floods. Marshland sites were further segregated into two groups (ANOSIM test: R = 0.777, P \ 0.01, n = 23) according to the Na + /Ca 2+ ratio (in meq l -1 ) at a threshold value of 25. An ordination by PCA showed that five variables grouped 81.4% of the total variance in two axes. The first PCA axis (60.7% of variance) separated temporary wetlands into ponds and marshland sites according to variables related to substrate and hydrology (Na + /Ca 2+ ratio, conductivity, water depth and flooding period). Other variables (e.g., water transparency, alkalinity, pH, submersed macrophyte biomass, phosphate, nitrate and planktonic chlorophyll concentrations) did not produce a significant segregation between marshland and pond sites during floods. Further discrimination within each wetland type was thus not achieved.

show abstract

Section: Discussionmentioning

confidence: 83%

A quantitative hydrogeomorphic approach to the classification of temporary wetlands in the Doñana National Park (SW Spain)

Espinar

Serrano

2008

Aquat Ecol

View full text Add to dashboard Cite

show abstract

“…The sterile sediment was added to the desired depth and moistened to ensure stability. The pots were then immersed very carefully so as not to disturb sediment in a tank in a greenhouse; the tank was filled with distiled water whose conductivity was adjusted to 3 mS/ cm by adding salt, so that salinity would not be limiting for any species (Grillas et al 1993a). The mean temperature was 14 °C (from 8 ° to 20 ° C) and lighting was natural daylight with a photoperiod of 9h30-10h30 days and 13h30-14h30 nights.…”

Section: Experiments 1 (Exp 1)mentioning

confidence: 99%

“…The last species was rarely recorded in the vegetation, almost certainly because of its low salt tolerance (Grillas et aL 1993a). In site 2, Charophytes, Callitriche truncata, Ranunculus baudotii and Zannichellia sp occurred both in the seed bank (Table 2) and in the vegetation (Grillas 1990).…”

Section: Composition Of the Seed Bank At Each Site And Changes Betwementioning

confidence: 99%

Vertical structure of seed banks and the impact of depth of burial on recruitment in two temporary marshes

Bonis

Lepart

1994

Vegetatio

Self Cite

View full text Add to dashboard Cite

The structure of the seed bank (including Chara oospores), in relation to depth within the sediment and disturbance, was studied in two Rh6ne delta temporary marshes for two years. The seeds of all species were concentrated in the top 2 cm of sediment with very low numbers beeing found below 4 cm. When an exclosure eliminated disturbances of the sediment by animals, the vertical repartition of seeds at site 2 was more pronounced than outside the exclosure.In experiment 1, the emergence capacity of seeds from different depths and buried under layers of sterile equivalent to those in the field was measured. Depending of the species, 22 to 98 ~o of the seeds germinated from unburied seeds in the top 2 cm. Only 1 ~o of the oospores of Chara (from site 2) at 2 to 4 cm depth in the sediment emerged.In experiment 2, surface seed bank samples were placed under 0, 2 or 4 cm sterile sediment depth. The samples contained numerous recent seeds and the emergence percentage reached 41 ~o (for Ruppia maritima). Only the seeds of Zannichellia spp failed to germinate from a depth of 2 cm or more. The emergence percentage from 2 cm depth or more was always lower than at the surface. These experiments showed that both burial and ageing of seeds decrease germination capacity.The majority of the active seeds located at the surface germinate when the marsh is flooded. Seeds located between 2 and 4 cm can be brought back to the surface by disturbances and play the role of a reserve involved in maintenance of populations that go without seed production for one or some years.Nomenclature: Tutin et al. (1964Tutin et al. ( -1980Talavera et al. (1986) for Zannichellia; Cotillion (1957) for the charophytes.

show abstract

“…The region is characterized by high temperatures (23°C average temperature in July) and drought in summer (79 mm average rainfall between June and August), associated with strong winds. Our study site, the Baisse Salée pond, is a typical temporary-flooded wetland subject to water management for waterfowl protection (Grillas et al, 1993).…”

Section: Experimental Sitementioning

confidence: 99%

Impact of seasonal sediment desiccation and rewetting on microbial processes involved in greenhouse gas emissions

Fromin¹,

Pinay²,

Montuelle³

et al. 2010

Ecohydrology

View full text Add to dashboard Cite

The response to spring desiccation and autumn (rainfall-related) rewetting of sediment microbial functioning was investigated in a Mediterranean seasonal pond. Surface (0-2 cm depth) and subsurface (2-10 cm) sediments were sampled during the pond emptying, the dry period, and after a rain event, and characterized for potential microbial activities [substrate-induced respiration (SIR), denitrification enzyme activity (DEA), and nitrification enzyme activity (NEA)]. Eddy covariance fluxes of CO 2 were also measured as an integrated value of the respiration of the sediment. Our results showed that short-term variations in the sediment water content can strongly affect the microbial functioning, whereas the metabolic structure of the microbial community was not strongly modified. The duration of the dry period influenced the intensity of microbial potentials and the surface layer responded differently from the subsurface layer, which was less affected by variations in water content. SIR and DEA were strongly stimulated during early summer desiccation of the sediment, while NEA was stimulated during late desiccation period. DEA and NEA potentials remained very high in sediment after 1 month of drought. Eddy covariance measurements confirmed that global CO 2 fluxes were enhanced during early desiccation, decreased under dry conditions, and finally re-enhanced after a rainfall. These results suggest that management of such ponds can influence CO 2 and N 2 O emissions, and that some precautions in the management (limitation of dry-wet alternations and duration of emptying) could help reduce greenhouse gas emissions.

show abstract

The effect of salinity on the dominance‐diversity relations of experimental coastal macrophyte communities

Cited by 26 publications

References 29 publications

A quantitative hydrogeomorphic approach to the classification of temporary wetlands in the Doñana National Park (SW Spain)

A quantitative hydrogeomorphic approach to the classification of temporary wetlands in the Doñana National Park (SW Spain)

Vertical structure of seed banks and the impact of depth of burial on recruitment in two temporary marshes

Impact of seasonal sediment desiccation and rewetting on microbial processes involved in greenhouse gas emissions

Contact Info

Product

Resources

About