Boudewijn Beltman - Academia.edu (original) (raw)

Papers by Boudewijn Beltman

Science of the Total Environment 1 402 70 81, Aug 25, 2008

Dutch water policy aims for more frequent, controlled flooding of river valley floodplains to avo... more Dutch water policy aims for more frequent, controlled flooding of river valley floodplains to avoid unwanted flooding elsewhere; in anticipation of increased flooding risks resulting from climate changes. Controlled flooding usually takes place in winter in parts of the valleys which had not been subject to flooding in the last decades. It may thus affect existing nature with its conservation values. The goal of this study was to clarify the geochemical and hydrological factors determining plant species composition of winter-flooded river valley grasslands. A correlative study was carried out in 43 sites in 13 Dutch river valley floodplains, with measurements of flooding regime, vegetation composition, soil nutrients and soil pH status. With the use of canonical correspondence analysis (CCA) the plant species composition was investigated in relation to the geochemical variables and the winter winter-flooding regime. We found that the distributions of target species and non-target species were clearly correlated with geochemical characteristics and flooding regime. Clustering of sites within the CCA plots has led us to distinguish between four types of winter flooding in our areas: floodplains with (a) accumulating rain water, (b) low groundwater levels flooded with river water, (c) discharging groundwater and (d) high groundwater levels flooded with river water. Our major conclusions are (1) the winter groundwater level of winter-flooded grasslands was important for evaluating the effects of winter flooding on the geochemistry and plant species composition, and (2) winter winter-flooding effects were largely determined by the nature of the flooding. A high frequency of flooding particularly favoured a small set of common plant species. In areas with groundwater seepage, winter flooding may provide geochemical conditions suitable for diverse vegetation types with rare species. Rainwater flooded sites appeared less suitable for most target species.

Wetlands Ecology and Management, 1992

This paper summarizes expected changes in hydrology, chemistry and biota of Dutch peatlands (bogs... more This paper summarizes expected changes in hydrology, chemistry and biota of Dutch peatlands (bogs, fens and moorland pools) caused by climatic changes resulting from the Greenhouse Effect. Special attention is paid to the interaction with atmospheric acid deposition. In both bogs and moorland pools prolonged drought periods may cause deleterious effects on biota because of the release of atmospherically-derived reduced sulphur compounds. In fenlands negative changes will be caused by eutrophication due to increased supply of allochtonous water. Long-term water and nutrient budgets are needed, along with better predictions of expected climate changes, to develop models of changes in hydrology, chemistry and biota of peatlands.

Wetlands Ecology and Management, 2005

Turbid water, high phosphorus (P)-loading and disappearing Chara communities forced local water a... more Turbid water, high phosphorus (P)-loading and disappearing Chara communities forced local water authorities to carry out restoration measures in the lakes and marshes of the Botshol The Netherlands. The reduction of the external-P input could be reached by chemical treatment of the brackish suppletion water and by separating the area from nearby agricultural areas. A side effect of these measures was an increase of chloride from 400 mg l À1 to 1000 mg l À1 in the surface water of Botshol. Internal biogeochemical processes were investigated with phytometers and direct measurements of soil nutrient availability in greenhouse experiments. The increased chloride levels were assumed to increase soil pore water P. The first experiment showed higher P in the peat-soils treated with the highest Cl-concentration and an increased leaching of PO 4 from the lake-bottom peat-soils. No reaction of the phytometer Epilobium hirsutum was found. In the second experiment the 800 mg l À1 Cl-treatment resulted in significantly higher biomass of Carex acutiformis grown on treated bank soil. N-uptake by the phytometer Carex acutiformis was significantly higher. The available-P and total-P in the bank soil did not show a treatment effect. The two studies showed under similar 'standardized' conditions a treatment effect of chloride on the P-availability, resulting in higher PO 4 leaching and increased plant nutrient concentrations and biomass. The field study showed higher available-P concentrations in the shore zone than in remote areas. The high chloride levels after restoration impact internal nutrient availability in the Botshol wetlands, on soil loaded with P in recent and historic times.

Wetlands Ecology and Management, 2004

Supplying polluted river water to nature reserves in The Netherlands often leads to eutrophicatio... more Supplying polluted river water to nature reserves in The Netherlands often leads to eutrophication of the reserve. The eutrophication can be caused directly by the high nutrient input (external eutrophication) or indirectly by altering nutrient availability due to changes in nutrient desorption or mineralization. This paper investigates the potential of a ditch system that is tested for its potential to improve the water quality of polluted river water prior to supplying to the wet meadow reserve De Meije in The Netherlands. Concentrations of the macro-ions chloride, sulphate, calcium and bicarbonate in the polluted river water were much higher than original background values, measured in the reserve. During transport of the river water through the ditch system, no decline was observed in the concentrations of these macro-ions. The phosphorus concentration, however, decreased along the flow path and was significantly negatively correlated with the distance from the inlet point. High phosphorus removal occurred in a stretch of the ditch system where submerged and free floating species such as Fontinalis antipyretica and Lemna trisulca were dominant. The N : P ratio of F. antipyretica was especially low (N : P < 5) at sampling stations where high phosphorus concentrations were measured. The high N : P ratio indicated a luxury consumption of phosphorus. With decreasing phosphorus concentrations, the N : P ratio of F. antipyretica increased to a maximum of N : P ¼ 25. The nutrient budget of the ditch system showed that supply of river water was the main input of phosphorus (12 kg P) whereas the main inputs of nitrogen of the ditch system were atmospheric deposition (66 kg N) and leaching from the wet meadows (44 kg N). For both nutrients, harvesting the aquatic vegetation in September was the main removal mechanism from the ditch system with 92 kg of nitrogen (80% of the annual input N) and 14 kg of phosphorus (95% of the annual P input) removed. It was concluded that the ditch system with aquatic vegetation could successfully remove nutrients from polluted river water. The concentrations of macro-ions, however, are not influenced by the ditch systems and internal eutrophication due to changes in adsorption or mineralization may still occur.

Science of The Total Environment, 2008

Restoration Ecology, 2011

Peat ponds have been restored widely in the Netherlands to enhance the available habitat for spec... more Peat ponds have been restored widely in the Netherlands to enhance the available habitat for species-rich plant communities that characterize the early succession stages toward land. Colonization success of 33 target aquatic species has been quantified in eight complexes of new ponds. It has been related to the lay-out of these ponds, the structure of the surrounding landscape, (historic) prevalence of source populations within the complex and within a perimeter of 10 km, and pond water quality. Colonization success was variable: between 6 and 26 target species had reached the complexes in 1998. This success was coupled to the first principal component (PC) in a principal component analysis (PCA) explaining 44% of the variation in 27 variables. This first PC correlated with historical perimeter and local within-complex species richness, the number of ponds in the complex, the SW orientation of ditches in these complexes and pH, and transparency of the water. Age of the ponds , area of open water (8-42%), and shoreline density (13-43 km/km 2 in the complex) did not contribute significantly to colonization success. Separation of the effect of a species-rich surrounding landscape, the possibility to disperse through that landscape, the spatial lay-out of the complex and transparency of the water were precluded by the strong covariance along the first PC. Probably all three are independently important. It is speculated that diel migration by waterfowl may be responsible for the dispersal of plant propagules to the pond complex, whereas within-complex dispersal to establishment sites is enhanced by wind and water movement.

Landscape Ecology, 1990

The effect of regional, subregional and local groundwater flow systems on mesotrophic fen ecosyst... more The effect of regional, subregional and local groundwater flow systems on mesotrophic fen ecosystems was studied in the polders of the Vecht River plain that borders the Pleistocene ice-pushed moraine of Het Gooi. Variation in the vegetation and in the habitat factors (groundwater and peat soil) of fens depends whether or not the fens are connected to the outflow of the regional groundwater system.

Journal of Vegetation Science, 2011

Question: Dutch fen areas have become embedded in intensively used landscapes, resulting in biodi... more Question: Dutch fen areas have become embedded in intensively used landscapes, resulting in biodiversity loss. Hence, plant species that colonize open water inducing the formation of species-rich floating peat mats have disappeared. Despite many restoration efforts, they have not returned. Is natural succession towards floating mats impeded by site conditions, dispersal limitations or changed biotic interactions? Location: Six Dutch fen reserves: De Deelen, De Weerribben, De Wieden, Westbroek, Molenpolder and Terra Nova.

Journal of Vegetation Science, 2007

Question: Do severe winter flood events lift the nutrient limitation of biomass production in a r... more 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.

Journal of Vegetation Science, 2014

Question: What is the role of wind in the dispersal of waterborne seeds in slowflowing and stagna... more Question: What is the role of wind in the dispersal of waterborne seeds in slowflowing and stagnant water bodies at different temporal and spatial scales? (i) Is there a direct effect of wind on seed dispersal speed and distance? (ii) Are prevailing wind conditions reflected in the seed deposition patterns during a year? (iii) What are the long-term (multiple year) effects of prevailing wind conditions on the pattern and composition of shoreline seed banks?

Archiv für Hydrobiologie, 2005

ABSTRACT A long-term study of eutrophication abatement in the Botshol Nature Reserve, the Netherl... more ABSTRACT A long-term study of eutrophication abatement in the Botshol Nature Reserve, the Netherlands, showed an intriguing response in this shallow lake. Beginning in 1988, the external nutrient load was reduced by hydrological segregation from agricultural areas and by chemical stripping of phosphorus from the water supply. A side effect of the hydrological segregation of Botshol from agricultural areas was an increase in chloride from 500 to 1000 mg l -1. In the first four years after the decrease in nutrient load, reductions were observed in phosphorus and chlorophyll a concentrations, as well as in the density of phytoplankton, zooplankton, and fish. Reduced phytoplankton density resulted in reduced turbidity and increased cover of Characeae from 2 to 80 %. Although the objective of re-establishing submerged macrophytes seemed to be attained, the clear water state appeared unstable. From 1993 onwards, the ecosystem alternated between turbid water with minor macrophyte production (1993-1995, 1999-2003) and clear water with abundant growth of aquatic plants (1996-1998). Phosphorus concentrations in Botshol also showed strong related fluctuations, despite a stable external phosphorus load.

Environmental Pollution, 2006

Ecosystems, 2010

Riparian ecosystems can harbor great diversity and provide important ecological functions such as... more Riparian ecosystems can harbor great diversity and provide important ecological functions such as improving water quality. The impact of eutrophication on riparian ecosystems, however, is unclear. We conducted a mesocosm experiment to study the effects of nutrient loading on riparian ecosystems. We specifically asked whether the source of nutrients in the riparian zone affects the complex interactions that occur between surface water and adjacent wetlands. We also studied litter decomposition in the wetland component of the mesocosms, because litter accumulation in fens is assumed to control succession toward floating mats. Each mesocosm consisted of an upland component, referred to as the bank, and a water compartment. The bank and water compartments were planted with typical riparian zone and open water fen species prior to the addition of nitrogen (N) and phosphorus (P) in different combinations to either the bank or the surface water. Nutrient addition (mainly P) resulted in increased plant production and higher expansion rates of plants on the bank and in the water. There were also clear interactions in plant responses between the bank and water. Only eutrophic species increased shoot densities after fertilization. Nutrient addition further resulted in higher litter production, especially on the banks, and stimulated decomposition. Both the plant responses and the litter experiment indicated that eutrophication would accelerate succession to floating mats. Such floating fen mats are not likely to have the typical species-rich combination of desirable species; however, as our results suggest that they would be dominated by a few eutrophic species.

Ecological Engineering, 1996

Species-rich plant communities characteristic for succession from mesotrophic open water to fen a... more Species-rich plant communities characteristic for succession from mesotrophic open water to fen are very rare in The Netherlands. These vegetation types used to occur in turf ponds in the low lying peatland area, created by peat dredging and filled with water due to seepage of mesotrophic, well-buffered groundwater. One of the goals of the National Nature Policy Plan is to create new opportunities for the initial terrestrialization communities through ecological engineering, e.g., restoration and creation of open water habitats. Restoration of the abiotic conditions in acidified floating fen communities is only possible by a combined measure of removal of the Sphagnum-layer and superficial drainage of surplus rain water. New turfponds have been excavated. This study showed that the abiotic conditions (i.e., water depth and water chemistry) are favorable for the development of aquatic communities characteristic of mesotrophic conditions. The aquatic plant species found in the new ponds also point in this direction, e.g., Chara major and Ch. delicatula are very abundant as are seven Potamogeton species. It is concluded that a constant discharge of groundwater and a good connectivity between the ponds and the existing remnants of plant communities desired in the area are essential for the conservation and development of these species-rich plant communities.

Bulletin of the Geobotanical Institute ETH, 2003

Summary 1 Hay meadows in western Ireland were traditionally mown once a year in late summer with ... more Summary 1 Hay meadows in western Ireland were traditionally mown once a year in late summer with aftermath grazing. To assess how changes in mowing regime affect the plant species composition, productivity and vegetation structure, a long-term mowing ...

Biogeochemistry, 2007

Climatic change has great impacts on stream catchments and their ecology. Expectations are that m... more Climatic change has great impacts on stream catchments and their ecology. Expectations are that more extreme climate events will result in undesired flooding in stream catchments. In the Netherlands, former floodplains with a history of agricultural use are put into use again as flooding areas for the purpose of water retention. This study focuses on the effects of winter flooding on various plant site conditions in the soil, such as redox, nutrient, pH, and base status. We compared the effects on groundwater-and rainwater-dominated floodplains. Water chemistry (pH, EC, HCO 3 , SO 4 , Cl, Ca, Mg, Na, K, p CO 2 , NO 3 , NH 4 , and PO 4 ) and soil nutrients (Total N and P, and bio-available P) were monitored for one year, including a 3-4 month period with winter flooding. In both floodplains no direct effect of the flood-water chemistry was detected in the pore water, because the soil pores had become saturated with groundwater or rainwater, respectively, just before flooding, flood-water did not penetrate the soil. We found that the increase in pH and ammonium concentration in the rainwater flood-plain were due to changes in redox status, resulting from the completely water-filled state of the soil pores during the flooding event. Furthermore, we noticed an increase in soil nutrient contents and a shift in plant species composition in the rainwater floodplain: the vegetation included more plant species characteristic for N-richness. Finally, we conclude that winter flooding has more drastic effects on biogeochemical conditions and vegetation composition in the atmotrophic conditions characteristic for low-order subcatchments than in lithotrophic conditions in the larger, higher-order subcatchments of the stream basin.

Hydrobiological Bulletin, 1976

Without Abstract

Turloughs are temporary wetlands almost unique to the west of Ireland. A transect of six vegetati... more Turloughs are temporary wetlands almost unique to the west of Ireland. A transect of six vegetation zones across a well-studied turlough in County Mayo was investigated. At each station along the transect, the relative frequency of vascular plants was recorded and environmental variables (soil pH, soil moisture, soil loss-on-ignition) and plant tissue concentrations of nitrogen (N), phosphorus (P) and potassium (K) were measured. The aim was to test whether Ellenberg indices (weighted by community composition and recently corrected for use in the British Isles) are effective as surrogates of environmental variables on turloughs. Results indicated that each vegetation zone formed a distinct vascular plant community and suggest that the Ellenberg F index is indeed a good model for hydrological variables, but more work is needed before the Ellenberg N and R indices can be accepted as dependable surrogates for relevant environmental variables on turloughs.