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Floodplain Grasslands (floodplain + grassland)

Distribution by Scientific Domains
Earth and Environmental Science100%

Selected Abstracts

Flood events overrule fertiliser effects on biomass production and species richness in riverine grasslands

JOURNAL OF VEGETATION SCIENCE, Issue 5 2007
Boudewijn Beltman
Abstract Question: Do severe winter flood events lift the nutrient limitation of biomass production in a river floodplain? How does this affect plant species richness? How long do the effects last? Location: Floodplain grassland on calcareous sandy loam near river Rhine in The Netherlands. Methods: Plots were fertilised with four treatments (control, N, P, N+P) for 21 years; plant species composition, vegetation biomass and tissue nutrient concentrations were determined every year between 1985 and 2005. Results: Fertilisation with N generally increased biomass production and reduced species richness, but these effects varied over time. During the first four years of the experiment, biomass production appeared to be co-limited by N and P, while N fertilisation dramatically reduced plant species richness; these effects became weaker subsequently. Following two extreme winter floods in 1993,94 and 1994,95 and a drought in spring 1996, the effects of fertilisation disappeared between 1998 and 2001 and then appeared again. Flooding caused an overall reduction in species richness (from c. 24 to 15 species m -2) and an increase in biomass production, which were only partly reversed after ten years. Conclusions: Long time series are necessary to understand vegetation dynamics and nutrient limitation in river floodplains, since they are influenced by occasional flood and drought events, whose effects may persist for more than ten years. A future increase in flooding frequency might be detrimental to species richness in floodplain grasslands. [source]

The decline of metallophyte vegetation in floodplain grasslands: Implications for conservation and restoration

APPLIED VEGETATION SCIENCE, Issue 1 2009
Esther C.H.E.T. Lucassen
Abstract Question: Which biogeochemical processes are responsible for the decline of endemic metallophyte vegetation in floodplain grasslands? Location: Floodplain grasslands along the River Geul (the Netherlands) and metalliferous mine spoils near the River Geul (Belgium). Methods: In order to find factors and soil processes that have caused a decline of metallophytes and an increase of pseudo-metallophytes in floodplain grasslands, a soil study was done at locations currently and formerly dominated by metallophytes. In addition, changes in soil chemistry in recent decades in floodplain grasslands were investigated. Finally, a 2-year plant growth experiment was performed in the field, to test the effects of improving soil conditions by topsoil removal. Results: Metallophytes only occur on acidic floodplain soils (pH-H2O 5.0-5.5) with relatively high Zn availability (total Zn >40 ,mol g,1; Zn/Ca>0.8; Zn-H2O>59 ,mol kg,1) combined with low phosphate availability (Olsen-P,1250 ,mol kg,1). The Olsen-P and total Ca concentrations were relatively high in topsoil (0-20 cm), while total Zn was high throughout the soil profile (0-50 cm). Removal of topsoil led to recovery of P and Zn availability. Under the new soil conditions there was almost no growth and expansion of pseudo-metalliferous grasses in time, wheras metallophytes easily established, maintained and reproduced with significant increases in cover over time. Conclusions: On a global scale, metallophyte vegetation types are increasingly under threat of extinction. Our study shows that factors leading to higher soil alkalinity inhibit Zn availability at the expense of the metallophyte vegetation. Factors leading to a higher Olsen-P concentration stimulate the growth of more competitive pseudo-metallophyte grasses. Both eutrophication and alkalinisation have contributed to the decline of metallophyte vegetation in floodplains of the River Geul. Removal of the alkaline- and phosphate-enriched soil top layer restores the original soil chemistry and enables re-colonisation by the metallophyte vegetation. The results can be applied in conservation and restoration strategies for such sites. [source]

Flood events overrule fertiliser effects on biomass production and species richness in riverine grasslands

JOURNAL OF VEGETATION SCIENCE, Issue 5 2007
Boudewijn Beltman
Abstract Question: Do severe winter flood events lift the nutrient limitation of biomass production in a river floodplain? How does this affect plant species richness? How long do the effects last? Location: Floodplain grassland on calcareous sandy loam near river Rhine in The Netherlands. Methods: Plots were fertilised with four treatments (control, N, P, N+P) for 21 years; plant species composition, vegetation biomass and tissue nutrient concentrations were determined every year between 1985 and 2005. Results: Fertilisation with N generally increased biomass production and reduced species richness, but these effects varied over time. During the first four years of the experiment, biomass production appeared to be co-limited by N and P, while N fertilisation dramatically reduced plant species richness; these effects became weaker subsequently. Following two extreme winter floods in 1993,94 and 1994,95 and a drought in spring 1996, the effects of fertilisation disappeared between 1998 and 2001 and then appeared again. Flooding caused an overall reduction in species richness (from c. 24 to 15 species m -2) and an increase in biomass production, which were only partly reversed after ten years. Conclusions: Long time series are necessary to understand vegetation dynamics and nutrient limitation in river floodplains, since they are influenced by occasional flood and drought events, whose effects may persist for more than ten years. A future increase in flooding frequency might be detrimental to species richness in floodplain grasslands. [source]

The decline of metallophyte vegetation in floodplain grasslands: Implications for conservation and restoration

APPLIED VEGETATION SCIENCE, Issue 1 2009
Esther C.H.E.T. Lucassen
Abstract Question: Which biogeochemical processes are responsible for the decline of endemic metallophyte vegetation in floodplain grasslands? Location: Floodplain grasslands along the River Geul (the Netherlands) and metalliferous mine spoils near the River Geul (Belgium). Methods: In order to find factors and soil processes that have caused a decline of metallophytes and an increase of pseudo-metallophytes in floodplain grasslands, a soil study was done at locations currently and formerly dominated by metallophytes. In addition, changes in soil chemistry in recent decades in floodplain grasslands were investigated. Finally, a 2-year plant growth experiment was performed in the field, to test the effects of improving soil conditions by topsoil removal. Results: Metallophytes only occur on acidic floodplain soils (pH-H2O 5.0-5.5) with relatively high Zn availability (total Zn >40 ,mol g,1; Zn/Ca>0.8; Zn-H2O>59 ,mol kg,1) combined with low phosphate availability (Olsen-P,1250 ,mol kg,1). The Olsen-P and total Ca concentrations were relatively high in topsoil (0-20 cm), while total Zn was high throughout the soil profile (0-50 cm). Removal of topsoil led to recovery of P and Zn availability. Under the new soil conditions there was almost no growth and expansion of pseudo-metalliferous grasses in time, wheras metallophytes easily established, maintained and reproduced with significant increases in cover over time. Conclusions: On a global scale, metallophyte vegetation types are increasingly under threat of extinction. Our study shows that factors leading to higher soil alkalinity inhibit Zn availability at the expense of the metallophyte vegetation. Factors leading to a higher Olsen-P concentration stimulate the growth of more competitive pseudo-metallophyte grasses. Both eutrophication and alkalinisation have contributed to the decline of metallophyte vegetation in floodplains of the River Geul. Removal of the alkaline- and phosphate-enriched soil top layer restores the original soil chemistry and enables re-colonisation by the metallophyte vegetation. The results can be applied in conservation and restoration strategies for such sites. [source]