Typha Domingensis Research Articles

Find Typha angustata (Typha L., Typhaceae) in the Delta of the Don River (Rostov Region)

The data on the discovery of the cornucopia of the narrowed Typha angustata in the delta of the Don River are given. In the “Flora of the USSR” this species was understood quite broadly, its range stretched from the Danube to the Pacific Ocean. For a long time, it was not found and was referred to as synonymous with T. australis, T. domingensis T. angustifolia. The species has not disappeared from the composition of the hydrophilic flora of Russia. It is preserved in the “arms” of the Delta of the Don River. As a result of isolations in the Cenozoic, which led to the severance links with the eastern and western water basins, the range was significantly reduced and the rate of evolution was reduced. In the modern geological period, T. angustata is undergoing natural elimination.

Effects of cattail intercropping with maize under different phosphorus concentrations and waterlogging

This work evaluated maize anatomy and physiology, under waterlogging, interacting or not with Typha domingensis at different phosphorus concentrations. Plants were transplanted to pots containing vermiculite waterlogged by a nutrient solution of different phosphorus concentration (0, 12.4, 24.8 mg P L-1) interacting or alone. The gas exchange parameters were analysed, leaves and roots collected and prepared accordingly to the usual methods of plant microtechnique. The slides were mounted and prepared for evaluation in an image analysis software. The experimental design was completely randomized in a factorial 3 x 2, and data were submitted to analysis of variance by Scott-Knott test for 5% probability. The presence of T. domingensis decreased root aerenchyma proportion and increased the gas exchange parameters, stomatal size and root apoplastic barriers under 24.8 mg P L-1. The intercropping is favourable under 24.8 mg P L-1.

Forbs from seasonal managed wetlands boost plankton production more than emergent graminoids by supplying novel labile detritus

Abstract Opportunities to enhance ecosystem functions exist in human‐dominated working landscapes, but understanding of key drivers is often lacking in these novel environments. In Suisun Marsh, California, USA, impounded managed wetlands designed to promote waterfowl incidentally support higher plankton densities—a key resource for imperilled pelagic fishes—than adjacent tidal habitats. Managed wetland operations could produce plankton at critical periods for fish and the aquatic food‐web more broadly, but drivers of plankton production in managed wetlands are poorly understood. We proposed that decaying vegetation resulting from controlled flooding in managed wetlands is important for stimulating plankton blooms, but that the effect varies by plant species and functional type. We conducted a mesocosm experiment to test the effects of different inundated plants on plankton production, including three forb species, three emergent graminoid species and a control treatment without added plant material. Forbs promoted larger phytoplankton blooms and higher zooplankton production—by an order of magnitude—than both emergent graminoids and the control treatment. Emergent graminoids supported larger phytoplankton blooms, but not higher zooplankton production, than the control treatment. Phytoplankton blooms exhibited pulse dynamics in all treatments, with densities increasing initially and crashing by the end of the experiment. Phytoplankton blooms in forb and emergent treatments lasted similar durations, counter to the expectation that emergent graminoids would support diminished production over a relatively prolonged period. Among zooplankton taxa, Daphnia magna and rotifers were strongly associated with all three forbs species while the nonnative cyclopoid copepod Limnothoina tetraspina were associated with cattails (Typha domingensis) and the control. Forbs temporarily depleted dissolved oxygen concentrations during the first week of the experiment, suggesting a tradeoff by which decaying forbs boost plankton production at risk of initial hypoxia. Our results suggest that seasonal drying and flooding operations in managed wetlands are likely to enhance plankton production because dry periods promote forb growth and subsequent flooding introduces labile forb material to the aquatic food web. Results also suggest that seasonal managed‐wetlands act as novel floodplain‐analogues, by which flood pulses drive productivity. Further research is needed to quantify production benefits and tradeoffs to the aquatic ecosystem at the landscape scale and to identify optimal management regimes that will help conserve imperilled species.

Plant species influences the composition of root system microbiome and its antibiotic resistance profile in a constructed wetland receiving primary treated wastewater.

Constructed wetlands (CWs) are nature-based solutions for wastewater treatment where the root system microbiome plays a key role in terms of nutrient and pollutant removal. Nonetheless, little is known on plant-microbe interactions and bacterial population selection in CWs, which are mostly characterized in terms of engineering aspects. Here, cultivation-independent and cultivation-based analyses were applied to study the bacterial communities associated to the root systems of Phragmites australis and Typha domingensis co-occurring in the same cell of a CW receiving primary treated wastewaters. Two endophytic bacteria collections (n = 156) were established aiming to find novel strains for microbial-assisted phytodepuration, however basing on their taxonomy the possible use of these strains was limited by their low degrading potential and/or for risks related to the One-Health concept. A sharp differentiation arose between the P. australis and T. domingensis collections, mainly represented by lactic acid bacteria (98%) and Enterobacteriaceae (69%), respectively. Hence, 16S rRNA amplicon sequencing was used to disentangle the microbiome composition in the root system fractions collected at increasing distance from the root surface. Both the fraction type and the plant species were recognized as drivers of the bacterial community structure. Moreover, differential abundance analysis revealed that, in all fractions, several bacteria families were significantly and differentially enriched in P. australis or in T. domingensis. CWs have been also reported as interesting options for the removal of emerging contaminants (e.g, antibiotic resistance genes, ARGs). In this study, ARGs were mostly present in the rhizosphere of both plant species, compared to the other analyzed fractions. Notably, qPCR data showed that ARGs (i.e., ermB, bla TEM, tetA) and intl1 gene (integrase gene of the class 1 integrons) were significantly higher in Phragmites than Typha rhizospheres, suggesting that macrophyte species growing in CWs can display a different ability to remove ARGs from wastewater. Overall, the results suggest the importance to consider the plant-microbiome interactions, besides engineering aspects, to select the most suitable species when designing phytodepuration systems.

Multivariate analysis of the summer herbaceous vegetation and environmental factors of the sub-tropical region

Understanding the distribution of the plant species of an unexplored area is the utmost need of the present-day. In order to collect vegetation data, Quadrat method was used having size of 1 m2. The composite soil samples from each site were tested for various edaphic properties. PC-ORD v.5 was used for the classification of the vegetation while CANOCO v.5.1 was used for ordination of the data and to find out the complex relationship between plants and environment. Survey was conducted during summer season and a total of 216 herbaceous species were recorded from forty different sites of District Kohat, Pakistan. Cluster Analysis (CA) and Two-Way Cluster Analysis (TWCA) classified the vegetation of forty sites into six major plant groups i.e., 1. Paspalum paspalodes, Alternanthera sessilis, Typha domingensis, 2. Cynodon dactylon, Parthenium hysterophorus, Brachiaria ramosa, 3. Cynodon dactylon, Eragrostis minor, Cymbopogon jwarancusa, 4. Cymbopogon jwarancusa, Aristida adscensionis, Boerhavia procumbens, 5. Cymbopogon jwarancusa, Aristida adscensionis, Pennisetum orientale and 6. Heteropogon contortus, Bothriochloa ischaemum, Chrysopogon serrulatus. They were named after the dominant species based on their Importance Value (IV). The detrended correspondence analysis (DCA) analysis further confirmed the vegetation classification. Canonical correspondence analysis (CCA) indicated that the species distribution in the area was strongly affected by various environmental factors including status, soil characteristics, topography and altitude.

Lindernia dubia (L.) Pennel as an Alien Weed in Central Spain: A Case Study.

Lindernia dubia (L.) Pennell is a species with invasive behavior outside of its native range of distribution (America), linked mainly to aquatic habitats. This annual species has been acknowledged as a weed in rice paddies in Europe and Asia. Due to the impacts of this invasive plant, some authors have even listed this species as a global invader. The present work focused on spontaneous plant species occurring in seedlings of Typha domingensis Pers. grown in central Spain for the establishment of constructed wetlands. Weed inventory revealed the presence of L. dubia as a dominant spontaneous species in this crop environment. A suite of mesocosm experiments were designed to study the population density of L. dubia versus that of the other dominant plant species, and to determine traits associated with its weedy potential. The results showed that L. dubia presents competitive attributes such as morphological variability, early flowering, long seeding time, short growth cycle, small and light seeds and a high seed production and germination rate (25 °C), meaning a high reproductive capacity in a cycle of about three months for plant growth in non-limiting conditions. The data obtained from this work provide a basis for understanding the weedy potential of L. dubia, and for management decisions of a potentially invasive species, which has been little investigated in Europe.

Geogrid-type geotextile made from Typha domingensis fibers with high tensile strength for erosion control

The present invention relates to a geotextile of the geogrid type manufactured with fibers from the Typha domingensis plant, known as cumbungi, recognized for its remarkable tensile strength. This geotextile is developed to mitigate erosive processes and is produced from natural fibers arranged in a mat configuration. This product fit in with the technical fields of civil engineering and textile materials. The central innovation of this geotextile lies in the provision of a natural alternative featuring biodegradable fibers and high tensile strength. Its applications in environmental engineering include erosion prevention, slope stabilization, and reinforcement of road structures, with the fundamental goal of preserving the soil against degradation and erosion. This high-strength geotextile is composed of Typha domingensis fibers skillfully interwoven and connected to form a grid structure, with each unit covering approximately 0.25 m2s. Furthermore, a double layer of waterproofing material is incorporated to provide greater cohesion, environmental durability, and tensile strength. In practical applications, this geotextile demonstrates a remarkable ability to withstand mass movements even before local vegetation develops. This makes it a technological alternative that synergistically combines technological and ecological processes, incorporating the principles of soil bioengineering while offering a sustainable alternative to synthetic geotextiles. The use of this geotextile in the field is preferably combined with living components such as seeds, plant stakes, wood, or rocks for slope or embankment stabilization, with a primary focus on effective erosion control and the promotion of environmental sustainability.

Comprehensive chemical profiling with UHPLC-MS, in-vitro, in-silico, and in-vivo antidiabetic potential of Typha domingensis Pers; A novel source of bioactive compounds

Aim of studyTypha is one of the valuable plant genera in folklore use in diabetes, and it can be a good source of bioactive chemicals. The current project was planned to investigate the pharmaceutical potential of n-butanol fraction of Typha domingensis Pers. (TDBF), a less explored medicinal plant. Materials and methodsThe phytochemical composition of the TDBF was assessed through a comprehensive analysis, encompassing the quantification of total bioactive contents (including total tannins and HPLC-PDA quantification) and a thorough exploration of secondary metabolites through scanning with UHPLC-MS. The pharmacological assessment included the determination of antioxidant activity (Total Antioxidant Capacity and Metal Chelating Assay), hemolytic potential, in-vitro antidiabetic effects (α-glucosidase and α-amylase inhibition, and antiglycation activity), as well as in-vivo antidiabetic activities. Molecular docking and ADMET studies were also performed for UHPLC-MS identified compounds. ResultsThe TDBF showed 134.76 ± 8.23 mg TAE/g total tannin contents. With HPLC-PDA, p-Hydroxy benzoic acid and p-Coumaric acid were quantified. During UHPLC-MS scanning, a total of five bioactive metabolites were identified in the negative mode, while 54 were detected in the positive mode. The in-vivo assessment of antidiabetic activity revealed a notable reduction in blood glucose levels in diabetic rats following treatment with the extract, demonstrating its efficacy compared to the control groups. Furthermore, the extract exhibited a positive impact on renal and liver function, evidenced by lowered levels of serum urea, ALT, ALP, creatinine, and a decrease in serum cholesterol levels. ConclusionThe results of this study showed that Typha domingensis Pers. possesses a variety of bioactive compounds and demonstrates notable potential in regulating diabetes. The study recommends further investigation into isolating these bioactive phytochemicals for their potential therapeutic applications across various diseases.

Influence of the Extraction Process on the Mechanical and Morphological Properties of Technical Fibers from Typha domingensis

ABSTRACT Typha is a fast-growing and invasive plant that spreads in the humid areas. Its proliferation has a negative impact on the local ecosystems. This study aims at the valorization of the by-products of this plant as biocomposites’ reinforcements. A mechanical extraction technique and retting in distilled water and sea water processes were developed to extract fibers from the leaves and stems of the Typha plants. SEM, FTIR analyses and monotonic tensile tests have been carried out to assess fibers’ properties. Morphological observations revealed that fibers extracted from the leaves were on average 48% finer than those from the stems. This fineness was more significant for the fibers retted in distilled water, that presented a smoother surface. The leaf fibers tensile properties (502, 247 and 372 MPa for the strength, 20.5, 14.2 and 12.8 GPa for the Young’s modulus and 2.47, 1.68 and 2.73% for maximum strain, respectively for the mechanical, distilled water and sea water retting processes) were on average 50% higher than for stem fibers, regardless of the extraction method. The results showed that the fibers elaborated had promising properties for biocomposite reinforcement. The extraction methods developed are low cost and without the use and generation of polluting chemicals

Innovative carbon materials from lignocellulosic wastes for electrochemical hydrogen peroxide production: Bridging biomass conversion and material properties

This study aims to assess the electrochemical generation of hydrogen peroxide and hydroxyl radicals (*OH) using carbon cathodes synthesized from three different lignocellulosic residues, Phragmites australis (PA), Cladium mariscus (CM) and Typha domingensis (TD). These vegetal species are commonly used in natural wetlands and phytoremediation processes and can accumulate recalcitrant pollutants within these treatment processes, generating a waste that should be properly managed. To convert these residues into valuable carbon materials, they underwent hydrothermal carbonization (HTC) followed by either chemical activation with KOH or pyrolysis at 1000 ºC. The best results were obtained with chemically activated materials, yielding a maximum H2O2 concentration of 313 mg L−1 with the carbon cathode produced from PA. The specific surface area, oxygenated functional groups and presence of structural defects in carbonous structures, were key parameters related to a good performance as catalysts towards the 2e- Oxygen Reduction Reaction (ORR). It was also demonstrated, in comparison with previous studies, that the presence of heavy metals in the structure of the lignocellulosic residue enhanced the decomposition of H2O2 into *OH. However, in the study of the degradation of a model organic contaminant as methylene blue (MB), it was shown that these *OH were not the main contributors to degradation, as direct H2O2 chemical degradation and adsorption on the carbon materials played the most significant role. Therefore, the outstanding capacity of these lignocellulosic residues as catalysts for the electrogeneration of H2O2 was confirmed, suggesting their potential future application in advanced oxidation processes for water decontamination.

Fiber extraction and characterization of Typha Domingensis Pers for the development of bio-composites: a renewable approach to minimize plastic usage in the field of agriculture

Fiber extraction and characterization of Typha Domingensis Pers for the development of bio-composites: a renewable approach to minimize plastic usage in the field of agriculture

Tolerance to mild shading levels in cattail as related to increased photosynthesis and changes in its leaf area and anatomy.

Shading is an environmental factor that has been little investigated regarding its effects on emergent aquatic plants. Typha domingensis Pers. is an emergent macrophyte that demonstrates some plasticity for self-shading, and as it can shade other species in the same area, the effect of shading on its traits deserves further investigation. The objective of the present study was to evaluate the gas exchange, leaf anatomy, and growth of T. domingensis cultivated under increasing shading intensities. The plants were collected and propagated in a greenhouse, and the clones were subjected to four shading intensities: 0% (unshaded), 35%, 73%, and 83% shading created by black nets. Growth traits, clonal production, photosynthesis, transpiration, and leaf anatomy were evaluated. The 73% and 83% shading promoted the death of all plants, but all plants survived in the 35% and unshaded treatments. Compared with the unshaded treatment, the 35% shading treatment promoted a higher photosynthetic rate and greater transpiration, supporting increased growth and production of clones. The increase in the photosynthetic rate in the 35% shading was related to the increase in leaf area which increased the photosynthesis of the whole plant. The 73% and 83% treatments inhibited the development of photosynthetic parenchyma and stomata in T. domingensis, leading to a drastic reduction in photosynthesis and energy depletion. Therefore, T. domingensis does not tolerate intense shading, but its photosynthetic characteristics and growth are favored by mild shading, a factor that may be of great importance for its competitiveness and invasive behavior.

Response of Typha domingensis during an accidental discharge of high Cr(VI) concentration in a full-scale treatment wetland

This work assesses the Cr accumulation and tolerance of Typha domingensis after an accidental discharge of wastewater that produced a concentration of Cr(VI) of approximately 120 mg L−1 in a free-water surface wetland. The wetland was constructed for the final wastewater treatment of a metallurgical manufacturing plant. It is 7 m wide, 20 m long, and waterproofed with a geomembrane. A 1.5 m soil layer was placed on top of the geomembrane. Water, plants, and sediment were sampled before and after an accidental discharge. The root anatomical measurements of the plants from the treatment wetland were compared with those of plants from an uncontaminated wetland (control). Roots and dead leaves from the inlet plants showed the highest Cr concentrations after the accidental discharge (12.4 and 11.6 mg g−1, respectively). SEM-EDX mapping determined that Cr was accumulated in root epidermis. Cr accumulation in plant detritus, plant roots, and sediment were the mechanisms for Cr removal. Plants accumulated Cr in belowground tissues demonstrating their potential for phytostabilization. T. domingensis was capable of modifying its morphology to respond to high Cr concentrations. This macrophyte is a suitable species for wetlands constructed for the treatment of a wastewater with high Cr(VI) concentration. The studied system was capable of minimizing the impact and preserving the environment.

Retracted: Chemical Composition and Biological Evaluation of Typha domingensis Pers. to Ameliorate Health Pathologies: In Vitro and In Silico Approaches.

[This retracts the article DOI: 10.1155/2022/8010395.].

Optimization and Characterization of Combined Degumming Process of <i>Typha angustata</i> L. Stem Fibers

Optimization and Characterization of Combined Degumming Process of <i>Typha angustata</i> L. Stem Fibers

Physiological and Ecological Study of some Algae and Aquatic Plants

The aim of the study was to find out the chemical content of some algae, Enteromorpha and Cladophora, and some selected aquatic plants, Typha domingensis, Phragmites australis and Schoenoplectus lacustris. were studied Ashes, fats and mineral elements, which include magnesium, phosphate and nitrogen, in addition to studying the physical and chemical properties of water at different times of the seasons. Enteromorpha moss showed the highest percentage of ash which amounted to (14.32%), magnesium (0.43%) and phosphate (2.73%) while Cladophora moss showed the highest percentage of fat which amounted to (7.28%) and nitrogen (3.92%). The plants showed clear significant differences in different seasons where the results showed that the highest value of ash for Typha domingensis was in spring (11.11%), for Phragmites australis in summer (12.43%) and for Schoenoplectus lacustris in autumn (16.21%). As for fats the highest value of fats was in the spring season for the Typha domingensis plant (3.10%), for the Phragmites australis plant in the autumn season (1.51%), and for the Schoenoplectus lacustris plant in the summer season (2.21%). As for magnesium, the highest value of magnesium was in the winter season for the Typha domingensis plant (0.25%), for the Phragmites australis plant in the summer season (0.76%), and for the Schoenoplectus lacustris plant in the autumn season (2.45%). As for phosphateits highest value was in the autumn season for the Typha domingensis plant (0.26%), for the Phragmites australis plant in the spring season (0.32%), and for the Schoenoplectus lacustris plant in the autumn season (0.24%). Also the physical and chemical properties of water showed great variations in different seasons as the highest recorded value of air and water temperature in summer was (41) and (40) Celsius respectively. As for the pH, the highest value was recorded in the winter season (8.16), and the nitrates recorded the highest value in the autumn season (45.35) mg / L.

Review on Aquatic Weeds and Their Management

When aquatic weeds grow too much, they pose a threat to fish farming. An essential component of pond management is weed control. Out of approximately 160 aquatic weeds, the primary focus in India revolves around Eichhornia crrassipes, Ipomoea aquatica, Typha angustata, Ceratophyllum demersum, Salvinia molesta, Nelumbo nucifera, Alternanthera philoxeroides, Hydrilla verticillata, Vallisneria spiralis, Chara spp., Nitelia spp., and Potamogeton spp. Aquatic weeds are rapidly expanding in several irrigation and hydropower projects across the nation, including the Kakki and Idikki reservoirs in Kerala, the Tungabhadra project in Karnataka, the Nagarjuna Sagar project in Andhra Pradesh and the Powai Lake in Maharashtra. Biological, chemical, and physical strategies can all be used to control aquatic weeds. Aquatic weeds can be stopped from spreading or eliminated using a few common control methods. Physical remedies work best for small-scale infestations, but they are expensive and prone to regrowth when used on big water bodies. Herbicide control of tiny infestations has frequently been quite successful, but it significantly depends on trained operators who keep a close eye out for the appearance of regrowth or seedlings over a lengthy period. The amount of nutrients released into water in recent decades has significantly increased from home and industrial sources as well as from land where fertilizers are applied or where clearing has increased run off. This essay examines the problems associated with eight aquatic weeds in India and the efforts made so far to control them through a range of techniques.

Differences in MCF-7 response to endocrine disruptors in waste, superficial, and treated water from Southern Brazil.

The aim of this study was to evaluate the effect of possible endocrine disruptors in surface and wastewater using a cell proliferation assay in an estrogen-responsive cell line (MCF-7). This study was conducted in the Sinos River (Brazil). The residual water was collected from a Pilot Treatment Plant (using Typha domingensis) and surface waters of the Luis Rau stream, the Sinos River, and the Water Treatment Station (WTS). After exposures (24-120h), a Sulforhodamine B assay was performed to determine the proliferation rate. The higher increase in proliferation rate was observed with the Luiz Rau stream and the sewage treated by macrophytes in a flotation filter. The results from WTS water remained with a proliferation rate similar to the negative control at all times, suggesting that the conventional treatment is partially effective for the withdrawal of endocrine-disrupting agents. The study demonstrated the efficiency of the MCF-7 line in assessing endocrine disruption caused by wastewater and surface water samples. Our results indicate that conventional water treatment can partially remove the polluting load of endocrine disruptors, minimizing their environmental and public health impacts. Besides, it demonstrates the need to expand sanitary services to improve the population's quality of life.

Typha domingensis and Phragmites australis as alternative and sustainable pulp materials for primary paper based packaging

Environmental pollution with plastic waste and deforestation has led to increase research into the development of new natural fibers. Typha domingensis and Phragmites australis was used to make sustainable paper sheet and rigid containers packaging. Characterization of structural, mechanical, barriers, safety and end-of-life properties of Typha paper coated with polyolefins or polylactic acid was performed. Cellulose extraction was done at, 10 % NaOH at 120 °C for 90 min, the cellulose and fibers of these plants were used to produce a paper sheet and trays. The results showed that sheets made from Typha were 100 % recyclable and, showed mechanical properties comparable (5900 MPa) to a commercial Mitsubishi paper (7000 MPa) at parity of grammage. Typha and Reeds trays were permeable to water vapors and oxygen, but resistant to fat. The results LCA analysis showed that Typha trays had an environmental impact three times lower than aluminum trays, the most use in Senegal.

The role of calcium and alkalinity on phosphorus removal by submerged aquatic vegetation in hardwater wetlands

The Everglades Stormwater Treatment Areas (STAs) are a 25,000 ha (61,000 acre) complex of constructed wetlands built to remove phosphorus (P) from agricultural and urban runoff in support of Everglades restoration. These STAs treat inflow waters that contain P in concentrations from 100 to 200 μg L−1, average calcium (Ca) concentrations of 60–90 mg L−1, and alkalinity (Alk) in the range of 150–350 mg L−1 as calcium carbonate (CaCO3). Photosynthesis, primarily from submerged aquatic vegetation (SAV) within these STAs, increases water pH resulting in CaCO3 formation, which is thought to contribute to P removal through coprecipitation and other processes. Since 2002, the STA complex has removed over 3000 MT of P and over 400,000 MT of Ca. Because the STAs at times treat Lake Okeechobee waters that are lower in Ca and Alk (35–50 mg L−1 and 95–125 mg L−1 as CaCO3, respectively), we conducted two experiments to explore the role of Ca and Alk on wetland P removal.First, in outdoor flow-through microcosms (0.18 m2) containing Najas guadalupensis and treating artificial inflow solutions, Ca/Alk at typical STA inflow concentrations (77 mg Ca L−1/316 mg L−1 as CaCO3) resulted in significantly lower outflow P concentrations compared to lower Ca/Alk treatments (28 mg Ca L−1/67 mg L−1 as CaCO3). Based on sediment organic carbon to total P (TP) ratios, organic matter production and sedimentation was the P removal mechanism under low Ca/Alk levels, where CaCO3 precipitation did not occur, and also under high Ca/Alk, low P (31 μg L−1) conditions, despite CaCO3 formation. High Ca/Alk increased organic matter sedimentation and associated P burial at low and high (168 μg L−1) water P concentrations. Additional P removal associated with CaCO3 precipitation occurred only under high Ca/Alk, high P concentrations, and accounted for about 47% of P sedimentation in those microcosms.Second, in flow-through mesocosms (4.75 m2) containing STA muck soil and common STA SAV species, elevated Ca/Alk (94 mg Ca L−1/185 mg L−1 as CaCO3) produced significantly lower outflow TP concentrations than treatments receiving unamended Lake Okeechobee inflow water with lower Ca/Alk concentrations (44 mg Ca L−1/112 mg L−1 as CaCO3). In the same experiment, Ca/Alk levels had no effect on P removal in mesocosms containing Typha domingensis, a common STA emergent macrophyte species. SAV mesocosms produced lower outflow TP concentrations than Typha, regardless of Ca/Alk levels. In a follow-on laboratory incubation, low Ca/Alk concentrations in incubation waters did not increase P release from sediments formed under prior low or high inflow Ca/Alk concentrations in the SAV mesocosms, but anoxia sharply increased P release from both.These experiments suggest that coprecipitation with CaCO3 is a meaningful P removal process in hardwater wetlands where high P concentrations and SAV coincide. Conversely, in STA outflow regions, where surface water P has already been treated to a low level, coprecipitation with CaCO3 probably does not contribute to further P reductions. However, Ca/Alk also may contribute to inorganic-C availability which influences submerged aquatic productivity, so the role of inorganic C limitation on STA vegetation communities and P removal merits further study.