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Jutta Papenbrock - One of the best experts on this subject based on the ideXlab platform.
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Halophyte Plants and Their Residues as Feedstock for Biogas Production—Chances and Challenges
Applied Sciences, 2021Co-Authors: Ariel E. Turcios, Aadila Cayenne, Hinrich Uellendahl, Jutta PapenbrockAbstract:The importance of green technologies is steadily growing. Salt-tolerant plants have been proposed as energy crops for cultivation on saline lands. Halophytes such as Salicornia europaea, Tripolium pannonicum, Crithmum maritimum and Chenopodium quinoa, among many other species, can be cultivated in saline lands, in coastal areas or for treating saline wastewater, and the biomass might be used for biogas production as an integrated process of biorefining. However, halophytes have different salt tolerance mechanisms, including compartmentalization of salt in the vacuole, leading to an increase of sodium in the plant tissues. The sodium content of halophytes may have an adverse effect on the anaerobic digestion process, which needs adjustments to achieve stable and efficient conversion of the halophytes into biogas. This review gives an overview of the specificities of halophytes that needs to be accounted for using their biomass as feedstocks for biogas plants in order to expand renewable energy production. First, the different physiological mechanisms of halophytes to grow under saline conditions are described, which lead to the characteristic composition of the halophyte biomass, which may influence the biogas production. Next, possible mechanisms to avoid negative effects on the anaerobic digestion process are described, with an overview of full-scale applications. Taking all these aspects into account, halophyte plants have a great potential for biogas and methane production with yields similar to those produced by other energy crops and the simultaneous benefit of utilization of saline soils.
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Screening of Emerging Pollutants (EPs) in Estuarine Water and Phytoremediation Capacity of Tripolium pannonicum under Controlled Conditions.
International journal of environmental research and public health, 2021Co-Authors: Ariel E. Turcios, Marie Hielscher, Bernardo Duarte, Vanessa F. Fonseca, Isabel Caçador, Jutta PapenbrockAbstract:The increasing number of pharmaceuticals in the environment and their difficult biodegradation, can lead to bioaccumulation in different trophic compartments. Their bioaccumulation can have negative consequences, especially in the generation of bacterial resistance by antibiotics, but also in the impairment of plant and animal metabolism. The Tejo estuary in Portugal is the habitat for many plant and animal species, which are also prone to this type of contamination. Therefore, in the present study different classes of emerging pollutants (EPs) were surveyed in water samples in the Tejo estuary, including antibiotics, anticonvulsants, antidepressants, lipid-lowering drugs, anti-inflammatory drugs, beta-blockers and analgesics. According to the results, only four compounds were detected in water samples collected at the three selected salt marshes, including carbamazepine, fluoxetine hydrochloride, venlafaxine hydrochloride and acetaminophen. Having the detected substances as a basis, a subsequent study was performed aiming to investigate the uptake and biodegradation capacity of halophytes, using Tripolium pannonicum as a model plant cultivated under controlled conditions with different concentrations of the found EPs. This experimental approach showed that T. pannonicum was able to uptake and degrade xenobiotics. Moreover, the application of sulfamethazine, as a model antibiotic, showed also that this species can uptake and degrade this compound, although the degradation rate and process proved to be compound-specific. This was also confirmed using crude plant extracts spiked with the different EPs. Thus this species is a potential candidate for the remediation of marine water and sediments contaminated with environmentally-significant EPs.
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uptake and biodegradation of the antimicrobial sulfadimidine by the species Tripolium pannonicum acting as biofilter and its further biodegradation by anaerobic digestion and concomitant biogas production
Bioresource Technology, 2016Co-Authors: Ariel E. Turcios, Dirk Weichgrebe, Jutta PapenbrockAbstract:Abstract This project analyses the uptake and biodegradation of the antimicrobial sulfadimidine (SDI) from the culture medium and up to the anaerobic digestion. Tripolium pannonicum was grown under hydroponic conditions with different concentrations of SDI (0, 5 and 10 mg·L −1 ) and the fresh biomass, containing different amounts of SDI taken up, was used as substrate for biogas production. SDI was analyzed by liquid chromatography coupled to positive ion electrospray mass spectrometry (ESI LC–MS). Based on the findings, T. pannonicum is able to uptake SDI. The more SDI is in the culture medium, the higher the SDI content in the plant tissue. According to this study, it is possible to produce high yields of biogas using biomass of T. pannonicum containing SDI and at the same time biodegradation of SDI is carried out. The highest specific biogas yield is obtained using shoots as substrate of the plants cultivated at 5 mg·L −1 SDI.
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Effect of salt and sodium concentration on the anaerobic methanisation of the halophyte Tripolium pannonicum
Biomass and Bioenergy, 2016Co-Authors: Ariel E. Turcios, Dirk Weichgrebe, Jutta PapenbrockAbstract:The halophyte species Sea Aster (Tripolium pannonicum) was grown with different concentrations of artificial seawater. In a second experiment, T. pannonicum was cultivated with a nutrient solution containing different concentrations of NaCl. This halophyte biomass was used to determine the biogas production potential. According to the findings, it is possible to produce high yields of methane using biomass from halophytes cultivated in the presence of salt. Biogas and methane yield are influenced by the salt content of the plant tissue, however, high concentrations of salt in the anaerobic reactors itself inhibit the biogas and methane production. The highest methane yield is obtained using plant substrates grown at 22.5 g L-1sea-salt with a value of 313 cm3g-1of VS. When treating T. pannonicum with different concentrations of NaCl, biogas and methane yields are highest when using plant substrates grown at 30 g L-1to produce values of 554 cm3g-1of VS and 447 cm3g-1of VS, respectively. Other research was carried out to study the effect of sodium on the biogas and methane yields using substrate from T. pannonicum cultured under non-saline conditions and adding different amounts of NaCl to the anaerobic reactors. Adding NaCl to the reactors decreases the biogas and methane production but using a salt-adapted inoculum increases the biogas yield in comparison to the non-adapted inoculum.
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Integrated multi-trophic aquaculture in a zero-exchange recirculation aquaculture system for marine fish and hydroponic halophyte production
Aquaculture International, 2015Co-Authors: Uwe Waller, Anne K. Buhmann, Anneliese Ernst, Verena Hanke, Andreas Kulakowski, Bert Wecker, Jaime Orellana, Jutta PapenbrockAbstract:The aim of the study was to investigate the feasibility of nutrient recycling from a marine recirculating aquaculture system (RAS) for fish (European sea bass, Dicentrarchus labrax L.) through three salt-tolerant, halophyte plant species, Tripolium pannonicum (Jacq.) Dobrocz., Plantago coronopus L., and Salicornia dolichostachya (Moss.). Halophytes, illuminated by sunlight and supplemented with artificial light, were maintained in hydroponic cultures integrated in a RAS water treatment system operating at 16 psu salinity. During a 35-day experiment, 248 fishes gained 5.6 kg of weight. Total plant biomass production reached 23 kg in 14 m^2 hydroponic culture area. Gain of shoot biomass was 27, 18, and 60 g m^−2 day^−1 for T. pannonicum , P. coronopus , and S. dolichostachya , respectively. The plants retained 7 g phosphorus and 46 g nitrogen under the experimental conditions. This was equivalent to 9 % of the N and 10 % of the P introduced with the fish feed. The edible part of the harvested plant material was microbially safe and approved for human consumption. The coupling of production in a RAS–IMTA was tested as a feasible cascading production technology for sustainable aquaculture.
Ariel E. Turcios - One of the best experts on this subject based on the ideXlab platform.
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Halophyte Plants and Their Residues as Feedstock for Biogas Production—Chances and Challenges
Applied Sciences, 2021Co-Authors: Ariel E. Turcios, Aadila Cayenne, Hinrich Uellendahl, Jutta PapenbrockAbstract:The importance of green technologies is steadily growing. Salt-tolerant plants have been proposed as energy crops for cultivation on saline lands. Halophytes such as Salicornia europaea, Tripolium pannonicum, Crithmum maritimum and Chenopodium quinoa, among many other species, can be cultivated in saline lands, in coastal areas or for treating saline wastewater, and the biomass might be used for biogas production as an integrated process of biorefining. However, halophytes have different salt tolerance mechanisms, including compartmentalization of salt in the vacuole, leading to an increase of sodium in the plant tissues. The sodium content of halophytes may have an adverse effect on the anaerobic digestion process, which needs adjustments to achieve stable and efficient conversion of the halophytes into biogas. This review gives an overview of the specificities of halophytes that needs to be accounted for using their biomass as feedstocks for biogas plants in order to expand renewable energy production. First, the different physiological mechanisms of halophytes to grow under saline conditions are described, which lead to the characteristic composition of the halophyte biomass, which may influence the biogas production. Next, possible mechanisms to avoid negative effects on the anaerobic digestion process are described, with an overview of full-scale applications. Taking all these aspects into account, halophyte plants have a great potential for biogas and methane production with yields similar to those produced by other energy crops and the simultaneous benefit of utilization of saline soils.
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Screening of Emerging Pollutants (EPs) in Estuarine Water and Phytoremediation Capacity of Tripolium pannonicum under Controlled Conditions.
International journal of environmental research and public health, 2021Co-Authors: Ariel E. Turcios, Marie Hielscher, Bernardo Duarte, Vanessa F. Fonseca, Isabel Caçador, Jutta PapenbrockAbstract:The increasing number of pharmaceuticals in the environment and their difficult biodegradation, can lead to bioaccumulation in different trophic compartments. Their bioaccumulation can have negative consequences, especially in the generation of bacterial resistance by antibiotics, but also in the impairment of plant and animal metabolism. The Tejo estuary in Portugal is the habitat for many plant and animal species, which are also prone to this type of contamination. Therefore, in the present study different classes of emerging pollutants (EPs) were surveyed in water samples in the Tejo estuary, including antibiotics, anticonvulsants, antidepressants, lipid-lowering drugs, anti-inflammatory drugs, beta-blockers and analgesics. According to the results, only four compounds were detected in water samples collected at the three selected salt marshes, including carbamazepine, fluoxetine hydrochloride, venlafaxine hydrochloride and acetaminophen. Having the detected substances as a basis, a subsequent study was performed aiming to investigate the uptake and biodegradation capacity of halophytes, using Tripolium pannonicum as a model plant cultivated under controlled conditions with different concentrations of the found EPs. This experimental approach showed that T. pannonicum was able to uptake and degrade xenobiotics. Moreover, the application of sulfamethazine, as a model antibiotic, showed also that this species can uptake and degrade this compound, although the degradation rate and process proved to be compound-specific. This was also confirmed using crude plant extracts spiked with the different EPs. Thus this species is a potential candidate for the remediation of marine water and sediments contaminated with environmentally-significant EPs.
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uptake and biodegradation of the antimicrobial sulfadimidine by the species Tripolium pannonicum acting as biofilter and its further biodegradation by anaerobic digestion and concomitant biogas production
Bioresource Technology, 2016Co-Authors: Ariel E. Turcios, Dirk Weichgrebe, Jutta PapenbrockAbstract:Abstract This project analyses the uptake and biodegradation of the antimicrobial sulfadimidine (SDI) from the culture medium and up to the anaerobic digestion. Tripolium pannonicum was grown under hydroponic conditions with different concentrations of SDI (0, 5 and 10 mg·L −1 ) and the fresh biomass, containing different amounts of SDI taken up, was used as substrate for biogas production. SDI was analyzed by liquid chromatography coupled to positive ion electrospray mass spectrometry (ESI LC–MS). Based on the findings, T. pannonicum is able to uptake SDI. The more SDI is in the culture medium, the higher the SDI content in the plant tissue. According to this study, it is possible to produce high yields of biogas using biomass of T. pannonicum containing SDI and at the same time biodegradation of SDI is carried out. The highest specific biogas yield is obtained using shoots as substrate of the plants cultivated at 5 mg·L −1 SDI.
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Effect of salt and sodium concentration on the anaerobic methanisation of the halophyte Tripolium pannonicum
Biomass and Bioenergy, 2016Co-Authors: Ariel E. Turcios, Dirk Weichgrebe, Jutta PapenbrockAbstract:The halophyte species Sea Aster (Tripolium pannonicum) was grown with different concentrations of artificial seawater. In a second experiment, T. pannonicum was cultivated with a nutrient solution containing different concentrations of NaCl. This halophyte biomass was used to determine the biogas production potential. According to the findings, it is possible to produce high yields of methane using biomass from halophytes cultivated in the presence of salt. Biogas and methane yield are influenced by the salt content of the plant tissue, however, high concentrations of salt in the anaerobic reactors itself inhibit the biogas and methane production. The highest methane yield is obtained using plant substrates grown at 22.5 g L-1sea-salt with a value of 313 cm3g-1of VS. When treating T. pannonicum with different concentrations of NaCl, biogas and methane yields are highest when using plant substrates grown at 30 g L-1to produce values of 554 cm3g-1of VS and 447 cm3g-1of VS, respectively. Other research was carried out to study the effect of sodium on the biogas and methane yields using substrate from T. pannonicum cultured under non-saline conditions and adding different amounts of NaCl to the anaerobic reactors. Adding NaCl to the reactors decreases the biogas and methane production but using a salt-adapted inoculum increases the biogas yield in comparison to the non-adapted inoculum.
Anne K. Buhmann - One of the best experts on this subject based on the ideXlab platform.
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Integrated multi-trophic aquaculture in a zero-exchange recirculation aquaculture system for marine fish and hydroponic halophyte production
Aquaculture International, 2015Co-Authors: Uwe Waller, Anne K. Buhmann, Anneliese Ernst, Verena Hanke, Andreas Kulakowski, Bert Wecker, Jaime Orellana, Jutta PapenbrockAbstract:The aim of the study was to investigate the feasibility of nutrient recycling from a marine recirculating aquaculture system (RAS) for fish (European sea bass, Dicentrarchus labrax L.) through three salt-tolerant, halophyte plant species, Tripolium pannonicum (Jacq.) Dobrocz., Plantago coronopus L., and Salicornia dolichostachya (Moss.). Halophytes, illuminated by sunlight and supplemented with artificial light, were maintained in hydroponic cultures integrated in a RAS water treatment system operating at 16 psu salinity. During a 35-day experiment, 248 fishes gained 5.6 kg of weight. Total plant biomass production reached 23 kg in 14 m^2 hydroponic culture area. Gain of shoot biomass was 27, 18, and 60 g m^−2 day^−1 for T. pannonicum , P. coronopus , and S. dolichostachya , respectively. The plants retained 7 g phosphorus and 46 g nitrogen under the experimental conditions. This was equivalent to 9 % of the N and 10 % of the P introduced with the fish feed. The edible part of the harvested plant material was microbially safe and approved for human consumption. The coupling of production in a RAS–IMTA was tested as a feasible cascading production technology for sustainable aquaculture.
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Optimization of culturing conditions and selection of species for the use of halophytes as biofilter for nutrient-rich saline water
Agricultural Water Management, 2015Co-Authors: Anne K. Buhmann, Uwe Waller, Bert Wecker, Jutta PapenbrockAbstract:Abstract Salt-tolerant plants can be used as biofilters for nutrient-rich saline water such as aquaculture process water. Tripolium pannonicum (Jacq.) Dobrocz. was used to determine optimal culturing conditions for an efficient biofilter performance in terms of nutrient recycling by plant uptake. This performance was evaluated by taking different parameters into account, such as biomass production, plant nitrogen and phosphorus uptake as well as physiological parameters and decrease of nitrate-N and phosphate-P concentrations in the experimental fluid. Afterwards, additional plant species known as edible were studied to follow the idea of generating valuable co-products beside the use as biofilter. It was shown that a nitrate-N concentration of at least 10 mg l −1 is necessary for reasonable biomass production. A phosphate-P concentration of 0.3 mg l −1 is sufficient, but higher concentrations promote the uptake of phosphate-P. The addition of iron in chelated form is required for the growth of healthy plant biomass; the addition of manganese is beneficial but not implicitly necessary. Salt concentrations lower than seawater salinity promote biomass production and nutrient uptake. The use of a hydroponic culture system is more suitable than sand or expanded clay culture if controlled conditions and nutrient recycling are desired. The five weeks experiment to compare different halophyte species in 0.24 m 2 tanks with nine plants each resulted in above ground fresh weight of 185 to 398 g and total uptake of nitrogen and phosphorus of 0.6 to 2.1 g and 0.1 to 0.4 g, respectively. All tested species have potential to serve as biofilter and source for valuable co-products. A promising application is the growth of halophytic vegetable plants in marine aquaponic systems.
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Manipulating the antioxidant capacity of halophytes to increase their cultural and economic value through saline cultivation
AoB PLANTS, 2014Co-Authors: Christian Boestfleisch, Niko B. Wagenseil, Anne K. Buhmann, Charlotte E. Seal, Ellie Merrett Wade, Adele Muscolo, Jutta PapenbrockAbstract:Halophytes, salt-tolerant plants, are a source of valuable secondary metabolites with potential economic value. The steady-state pools of many stress-related metabolites are already enhanced in halophytes when compared with glycophytes, but growth under conditions away from the optimum can induce stress and consequently result in changes to secondary metabolites such as antioxidants. However, direct evidence for increasing the concentration of valuable secondary metabolites as a consequence of altering the salinity of the growing environment still remains equivocal. To address this, we analysed a range of metabolites with antioxidant capacity (including total phenols, flavonoids, ascorbate, reduced/oxidized glutathione and reactive oxygen species scavenging enzymes) in seedlings and plants from different families (Amaranthaceae, Brassicaceae, Plantaginaceae and Rhizophoraceae) and habitats grown under different salt concentrations. We show that it is possible to manipulate the antioxidant capacity of plants and seedlings by altering the saline growing environment, the length of time under saline cultivation and the developmental stage. Among the species studied, the halophytes Tripolium pannonicum, Plantago coronopus, Lepidium latifolium and Salicornia europaea demonstrated the most potential as functional foods or nutraceuticals.
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Research Article SPECIAL ISSUE: Physiology and Ecology of Halophytes—Plants Living in Salt-Rich Environments Manipulating the antioxidant capacity of halophytes to increase their cultural and economic value through saline cultivation
2014Co-Authors: Christian Boestfleisch, Niko B. Wagenseil, Anne K. Buhmann, Charlotte E. Seal, Ellie Merrett Wade, Adele Muscolo, Jutta PapenbrockAbstract:Halophytes, salt-tolerant plants, are asource of valuable secondary metabolites with potential economic value. The steady-state pools of manystress-related metabolites are alreadyenhanced in halophytes when compared with glycophytes, but growth under conditions away from the optimum can induce stress and consequently result in changes to secondary metabolites such as antioxidants. However, direct evidence for increasing the concentration of valuable secondary metabolites as a consequence of altering the salinity of the growing environment still remains equivocal. To address this, we analysed a range of metabolites with antioxidant capacity (including total phenols, fla- vonoids, ascorbate, reduced/oxidized glutathione and reactive oxygen species scavenging enzymes) in seedlings and plants from different families (Amaranthaceae, Brassicaceae, Plantaginaceae and Rhizophoraceae) and habitats grown under different salt concentrations. We show that it is possible to manipulate the antioxidant capacity of plants and seedlings by altering the saline growing environment, the length of time under saline cultivation and the develop- mentalstage.Amongthespeciesstudied,thehalophytes Tripolium pannonicum, Plantago coronopus, Lepidium latifolium and Salicornia europaea demonstrated the most potential as functional foods or nutraceuticals.
Dirk Weichgrebe - One of the best experts on this subject based on the ideXlab platform.
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uptake and biodegradation of the antimicrobial sulfadimidine by the species Tripolium pannonicum acting as biofilter and its further biodegradation by anaerobic digestion and concomitant biogas production
Bioresource Technology, 2016Co-Authors: Ariel E. Turcios, Dirk Weichgrebe, Jutta PapenbrockAbstract:Abstract This project analyses the uptake and biodegradation of the antimicrobial sulfadimidine (SDI) from the culture medium and up to the anaerobic digestion. Tripolium pannonicum was grown under hydroponic conditions with different concentrations of SDI (0, 5 and 10 mg·L −1 ) and the fresh biomass, containing different amounts of SDI taken up, was used as substrate for biogas production. SDI was analyzed by liquid chromatography coupled to positive ion electrospray mass spectrometry (ESI LC–MS). Based on the findings, T. pannonicum is able to uptake SDI. The more SDI is in the culture medium, the higher the SDI content in the plant tissue. According to this study, it is possible to produce high yields of biogas using biomass of T. pannonicum containing SDI and at the same time biodegradation of SDI is carried out. The highest specific biogas yield is obtained using shoots as substrate of the plants cultivated at 5 mg·L −1 SDI.
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Effect of salt and sodium concentration on the anaerobic methanisation of the halophyte Tripolium pannonicum
Biomass and Bioenergy, 2016Co-Authors: Ariel E. Turcios, Dirk Weichgrebe, Jutta PapenbrockAbstract:The halophyte species Sea Aster (Tripolium pannonicum) was grown with different concentrations of artificial seawater. In a second experiment, T. pannonicum was cultivated with a nutrient solution containing different concentrations of NaCl. This halophyte biomass was used to determine the biogas production potential. According to the findings, it is possible to produce high yields of methane using biomass from halophytes cultivated in the presence of salt. Biogas and methane yield are influenced by the salt content of the plant tissue, however, high concentrations of salt in the anaerobic reactors itself inhibit the biogas and methane production. The highest methane yield is obtained using plant substrates grown at 22.5 g L-1sea-salt with a value of 313 cm3g-1of VS. When treating T. pannonicum with different concentrations of NaCl, biogas and methane yields are highest when using plant substrates grown at 30 g L-1to produce values of 554 cm3g-1of VS and 447 cm3g-1of VS, respectively. Other research was carried out to study the effect of sodium on the biogas and methane yields using substrate from T. pannonicum cultured under non-saline conditions and adding different amounts of NaCl to the anaerobic reactors. Adding NaCl to the reactors decreases the biogas and methane production but using a salt-adapted inoculum increases the biogas yield in comparison to the non-adapted inoculum.
Davy, Anthony J. - One of the best experts on this subject based on the ideXlab platform.
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Manipulating saltmarsh microtopography modulates the effects of elevation on sediment redox potential and halophyte distribution
'Wiley', 2020Co-Authors: Mossman Hannah, Grant Alastair, Davy, Anthony J.Abstract:1. Halophyte distributions on saltmarshes are strongly related to elevation in the tidal frame. However, collinearity between elevation, the consequent inundation regime, and sediment waterlogging/redox potential obscures the proximate causes of distribution patterns. We sought to distinguish the effects of elevation per se from those of waterlogging by manipulating microtopography. 2. We experimentally manipulated elevation by ±15 cm at locations that spanned the elevation ranges of three saltmarshes recently reactivated by managed coastal realignment. Experimental plots were initially cleared of any vegetation. Elevation and sediment redox potential were determined for each plot. We planted five perennial species (Armeria maritima, Atriplex portulacoides, Limonium vulgare, Plantago maritima and Triglochin maritima) in half of the plots, recording survival over four years, and monitored natural colonisation of the other plots. 3. Overall, redox potential increased with elevation. Sediments were more oxidising in raised plots and more reducing in lowered plots. Redox reductions in lowered plots were in line with those that would be predicted from the overall redox/elevation relationship, but increases in raised plots were greater than predicted from elevation alone. 4. Plant colonisation and survival was poorer in lowered plots and, for most species, improved in raised plots. This can, in part, be attributed to the concomitant alterations in redox potential and elevation in the tidal frame, but microtopographic manipulation also had substantial independent effects on plant performance, including on the survival of all planted species and the colonisation of Puccinellia maritima, Salicornia europaea agg. and Tripolium pannonicum. 5. Synthesis: Microtopography can have effects on sediment chemistry and plant performance similar in magnitude to those of overall tidal elevation. Understanding how its effects modulate the relationship between tidal elevation, redox and other environmental conditions helps clarify the abiotic factors that fundamentally determine halophyte colonisation and survival. These results support the use of topographic manipulation to enhance the diversity of created saltmarshes
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Data from: Manipulating saltmarsh microtopography modulates the effects of elevation on sediment redox potential and halophyte distribution
2019Co-Authors: Mossman, Hannah L., Grant Alastair, Davy, Anthony J.Abstract:1. Halophyte distributions on saltmarshes are strongly related to elevation in the tidal frame. However, collinearity between elevation, the consequent inundation regime, and sediment waterlogging/redox potential obscures the proximate causes of distribution patterns. We sought to distinguish the effects of elevation per se from those of waterlogging by manipulating microtopography. 2. We experimentally manipulated elevation by ±15 cm at locations that spanned the elevation ranges of three saltmarshes recently reactivated by managed coastal realignment. Experimental plots were initially cleared of any vegetation. Elevation and sediment redox potential were determined for each plot. We planted five perennial species (Armeria maritima, Atriplex portulacoides, Limonium vulgare, Plantago maritima and Triglochin maritima) in half of the plots, recording survival over four years, and monitored natural colonisation of the other plots. 3. Overall, redox potential increased with elevation. Sediments were more oxidising in raised plots and more reducing in lowered plots. Redox reductions in lowered plots were in line with those that would be predicted from the overall redox/elevation relationship, but increases in raised plots were greater than predicted from elevation alone. 4. Plant colonisation and survival was poorer in lowered plots and, for most species, improved in raised plots. This can, in part, be attributed to the concomitant alterations in redox potential and elevation in the tidal frame, but microtopographic manipulation also had substantial independent effects on plant performance, including on the survival of all planted species and the colonisation of Puccinellia maritima, Salicornia europaea agg. and Tripolium pannonicum. 5. Synthesis: Microtopography can have effects on sediment chemistry and plant performance similar in magnitude to those of overall tidal elevation. Understanding how its effects modulate the relationship between tidal elevation, redox and other environmental conditions helps clarify the abiotic factors that fundamentally determine halophyte colonisation and survival. These results support the use of topographic manipulation to enhance the diversity of created saltmarshes
