Knowledge of nutrient accumulation and partitioning in plants is important to determine the optimum timing of harvesting during phytoremediation of biosolids. This research showed that a greater proportion of nitrogen (N) and phosphorus (P) absorbed by cattail and switchgrass was partitioned to the aboveground biomass (AGB), but this partition decreased after the onset of nutrient retranslocation to roots. Therefore, AGB should be harvested prior to retranslocation in order to optimize nutrient phytoextraction. Trace elements partitioned preferentially to the root biomass, indicating that AGB harvesting will have little impact on their phytoextraction. Net mineralized N concentration (Nmin) in biosolids from the primary lagoon cell was optimized near field capacity [60% water filled pore space (WFPS) but changed little under drier conditions (30% WFPS). Under near-saturation conditions (90% WFPS), net Nmin decreased with incubation time, likely due to reduced mineralization and denitrification. Available (Olsen) P concentration was not affected by moisture content.

The Cienega de Santa Clara is a 5600 ha, anthropogenic wetland in the delta of the Colorado River in Mexico. It is the inadvertent creation of the disposal of brackish agricultural waste water from the U.S. into the intertidal zone of the river delta in Mexico, but has become an internationally important wetland for resident and migratory water birds. The marsh is dominated by Typha domengensis with Phragmites australis as a sub-dominant species in shallower marsh areas. The most important factor controlling vegetation density was fire. The second significant (P<0.01) factor controlling NDVI was flow rate of agricultural drain water from the U.S. into the marsh. Reduced summer flows in 2001 due to canal repairs, and in 2010 during the YDP test run, produced the two lowest NDVI values of the time series from 2000 to 2011 (P<0.05). Salinity is a further determinant of vegetation dynamics as determined by greenhouse experiments, but was nearly constant over the period 2000 to 2011, so it was not a significant variable in regression analyses. Evapotranspiration (ET) and other water balance components were measured in Cienega de Santa Clara; we used a remote sensing algorithm to estimate ET from meteorological data and Enhanced Vegetation Index values from the Moderate Resolution Imaging Spectrometer (MODIS) sensors on the Terra satellite. We used Landsat NDVI imagery from 1978-2011 to determine the area and intensity of vegetation and to estimate evapotranspiration (ET) to construct a water balance. Remote sensing data was supplemented with hydrological data, site surveys and literature citations. The vegetated area increased from 1978 to 1995 and has been constant at about 4200 ha since then. The dominant vegetation type is Typha domingensis (southern cattail), and peak summer NDVI since 1995 has been stable at 0.379 (SD = 0.016), about half of NDVI(max). About 30% of the inflow water is consumed in ET, with the remainder exiting the Cienega as outflow water, mainly during winter months when T. domingensis is dormant.

O uso de agroquímicos pode causar uma grande variedade de impactos negativos em ambientes aquáticos. Em áreas de exploração agrícola, onde são usados tais produtos, há uma demanda por sistemas de bioremediação que conjuguem baixos custos e simplicidade operacional. Na presente tese são apresentados os resultados da pesquisa que consistiu em se investigar o destino ambiental do agroquímico ametrina quando adicionado a alagados construídos. Foram utilizados sistemas em micro e mesoescala, construídos em Viçosa-MG, que consistiam de macrófitas aquáticas (T. latifolia) plantadas sobre um leito de brita. Para melhor avaliação dos mecanismos nos alagados foi realizado um estudo hidrodinâmico e observou-se que as células operam com boa eficiência hidráulica. No experimento em mesoescala verificou-se a retenção/remoção de 39% da massa de ametrina aplicada, não sendo observadas diferenças significativas entre as 4 unidades utilizadas. No estudo em microcosmo, não foram observadas variações em relação ao teor de nutrientes e a morfo-anatomia das macrófitas. Tal fato pode ser interpretado positivamente, visto que mesmo sob perturbação ambiental a planta adulta conseguiu manter suas características. Como fator a ser considerado, verificou-se que o desenvolvimento inicial da T. latifolia pode ser prejudicado por reduzidas concentrações de ametrina. De uma maneira geral, observou-se que sistemas alagados construídos operando sob escoamento subsuperficial poderão vir a ser usados na mitigação da contaminação de águas por praguicidas. / Pesticides can cause a great spectrum of negative impacts in aquatic environmental. In agricultural lands, these products are largely used and in these regions there is a demand for low costs and simple bioremediation systems. In the present thesis, the results of the research about ametryn environmental fate in subsurface flow constructed wetlands systems are presented. The wetlands cells were built in microcosms and mesocosms scales at Viçosa city, Minas Gerais state. The experimental system was consisted of aquatic macrophytes (T. latifolia) cultivated on a porous gravel bed. A hydrodynamic study was performed for the better knowledge of the mechanisms of pesticide transport. The cells presented good hydraulic efficiency and in mesocosms wetlands were observed that 39% of ametryn amended was removed/retained. No statistical difference among the 4 cells performances was registered. At green house (microcosm) tests, no effects in nutrients and morpho-anatomy were observed. This fact can be interpreted positively, because ever under environmental disturbance, the macrophyte maintained its characteristics. However, aqueous 10-d germination and growth experiment indicate possible ametryn harmful effects to T. latifolia development. In general way, it was observed that vegetated constructed wetlands can be used in depollution of pesticides-contaminated waters.

Cattails (Typha spp.) are invasive and tend to decrease the biodiversity and area of open water of marshes, particularly where the natural hydrological cycles have been altered, as in Delta Marsh, Manitoba. Understanding the distribution of T. latifolia L., T. angustifolia L., their hybrid, T. x glauca Godr., and the environmental variables associated with their habitats, may give valuable insight for managing cattails. The distribution of these cattail species and hybrid were surveyed in 2011 in prairie pothole and roadside ditch marshes across southwestern Manitoba and southeastern Saskatchewan. Plants were identified by analysis of microscopic leaf-lamina margin characteristics. T. x glauca was most widespread, followed by T. latifolia, whereas T. angustifolia was rare and only found as far west as central Manitoba. Current understanding of the correlations between cattail invasions and their environment is conflicting and largely based on lacustrine wetland studies. A generalized linear model was developed. The model explained approximately 40% of the variation in T. x glauca distribution in the prairie potholes and ditches. The model included the environmental variables of sediment Olsen-P, sediment nitrate-N, water pH, litter depth, surrounding land use, and the interaction between Olsen-P and nitrate-N. Olsen-P was the most important of these variables, because its removal from the model significantly reduced the residual deviance of the model (P=0.05). In a survey of 13 transects throughout Delta Marsh in 2009, hybrid cattail, T. x glauca, was dominant, T. angustifolia was rare, and T. latifolia was absent. ANOVA linear regression (P=0.05) revealed that above-ground biomass was correlated with mean cattail ramet height, cattail ramet density, and standing litter biomass. Cattail ramet density was negatively correlated with sampling date and positively correlated with standing litter biomass. Mean cattail height was correlated with fallen litter biomass. One-way ANOVA (P=0.05) revealed that fallen litter biomass was lowest in quadrats closer to the open water, and mean cattail height was greatest at the quadrats closest to the open water. While mean cattail height differed depending on whether the cattail stand was a hybrid monoculture or a mixed stand of T. x glauca and T. angustifolia, no other cattail population variables were correlated with stand type. As revealed by one-way ANOVA (P=0.05), water conductivity, sediment texture, total-N, nitrate-N, Olsen-P, and organic-C were not important variables in the distributions of T. x glauca or T. angustifolia at Delta Marsh. Therefore, managing the nutrient levels at Delta Marsh would not likely be important for limiting the distribution of the cattails at this marsh. However, reducing the P concentration in pothole and ditch marshes may limit cattails in those environments.

High levels of phosphorus loading in Lake Winnipeg, Manitoba, Canada are causing eutrophication and algal blooms of increasing intensity and frequency. Phosphorus is also a strategic and limited natural resource critical for plant growth, and essential for agriculture and global food security. This research study demonstrated an innovative environmental engineering approach to address multiple sustainable development challenges. Cattail (Typha spp.), a large competitive emergent aquatic plant, was harvested to capture and remove nutrients that would otherwise cause eutrophication in aquatic systems, and utilized as a biomass material for industry. Cattail reaches maturity in less than 90 days, and late summer/early fall harvests yielded average 15 to 20 t DM/ha, and captured 30 to 60 kg/ha/year of phosphorus. Once harvested, nutrients locked in plant tissue are prevented from being released into the environment via natural decomposition. Utilizing harvested biomass as a bioenergy feedstock provided a further benefit displacing fossil fuels for heating, and generated valuable carbon offsets. Cattail was compressed into densified fuel products, and combustion trials revealed an average calorific heat value of 17 MJ/kg to 20 MJ/kg, comparable to commercial wood pellets. Average ash content was 5 to 6%, and no major concerns identified regarding combustion emissions and ash. Estimated greenhouse gas (GHG) mitigation potential from coal displacement was one tonne of cattail biomass generated 1.05 tonnes of CO2 offsets. Additionally, up to 88 % of total phosphorus was recovered in ash following combustion in solid fuel burners. Harvesting cattail biomass offers greatest feasibility if combined for multiple purposes: nutrient capture, habitat, bioenergy, carbon offsets, water quality credits, and higher value end products and biomaterials (i.e. biochar). Economics of harvesting need to be further explored at the pilot and commercial scale for this novel renewable and sustainable ecological biomass feedstock. From an agricultural context, this biomass resource is presently undeveloped. It is a plant species prized for its nutrient capture and water quality benefits, and a biomass feedstock for bioenergy and high value end-products that grows on marginal agricultural land, not competing with prime land and food crops.

Made available in DSpace on 2014-07-29T15:01:49Z (GMT). No. of bitstreams: 1 Dissertacao Lorena L M Abrantes.pdf: 4341681 bytes, checksum: 30126c561a517a7154d7108de137e004 (MD5) Previous issue date: 2009-08-28 / This study aimed to assess the efficiency of two vegetal species in the treatment of the sanitary sewer, in constructed wetlands system. Specifically, it aimed to evaluate the efficiency of the species Typha angustifolia (narrow-leaf cattail) and Phragmites australis (common reed), in their possible combinations, in the treatment of the sanitary sewer, in a constructed wetlands system, of vertical subsuperficial flux, with two flux directions (ascendant and descendant), related to the attributes: organic material, apparent color, ammonium nitrogen, phosphate, turbidity, chlorides, hardness, electrical conductivity, solids and thermotolerant coliforms. The experiment was conducted in the Researching Station in Sewer Treatment with Plants RSSTP (UFG), located in the Sewer Treatment Station (STS) Samambaia, in Goiânia, Goiás State, Brazil. The experimental unit has twenty four modules, grouped sequences of two modules (initial and final modules). Raw sewage which comes from the initial part of the ETE facultative pond was pumped into the deep of the treatment initial modules, filled up with substrate layers (in the deep filled up with rocks category number 3, followed by rocks category number 1, washed sand, and again rocks category number 1) and planted with cattail or reed. After going up by the vegetated substrate (ascendant vertical flux) the sewer was drained and conducted to the final treatment modules equally filled up and vegetated with one of the species, although being applied in the surface and drained by the deep (vertical descendant flux). The tax of sewer application was of 80 L.m-2dia-1, corresponding to a treatment area of 2 m2 per inhabitant. A year after the system implementation, during the period of 6 months, sewer samples were collected after passing through the flux sequences, each one with the combination of the two vegetal species, for the evaluation of the sewer attributes and calculation of the efficiency in the treatment. The results were analyzed by the Statistical Analysis System (SAS program), being used the tests F and the Tukey Kramer, considering 5% of probability. There were no meaningful differences in the efficiency of the treatments in the removal of the attributes: biochemical oxygen demand, chemical oxygen demand, ammonium nitrogen, phosphate, thermotolerant coliforms, chlorides, hardness, dissolved total solids and volatile total solids. The cattail was more efficient in the apparent color removal and turbidity. The reed presented more efficiency in the total solids removal. The position of the plant in the module sequence did not influence the apparent color and turbidity removals. The reed in the final module increased the removal of the attributes total solids and fixed total solids. It´s possible to verify that the technology of sewer treatment by using plants is efficient, since the species cattail and reed in the adopted system, provided results with removals higher 60% for the of the attributes: biochemical oxygen demand, chemical oxygen demand, apparent color, ammonium nitrogen, phosphate, thermotolerant coliforms and turbidity. / O presente estudo teve como objetivo avaliar a eficiência de duas espécies vegetais no tratamento do esgoto sanitário, em um sistema de alagados construídos. Especificamente, objetivou-se avaliar a eficiência das espécies Typha angustifolia (Taboa) e Phragmites australis (Caniço), em suas combinações possíveis, no tratamento de esgoto sanitário, em um sistema de alagados construídos, de fluxo subsuperficial vertical, com dois sentidos de fluxo (ascendente e descendente), concernente aos atributos: matéria orgânica, cor aparente, nitrogênio amoniacal, fosfato, turbidez, cloretos, dureza, condutividade elétrica, sólidos e coliformes termotolerantes. O experimento foi conduzido na Estação de Pesquisas em Tratamento de Esgotos com Plantas Eptep (UFG), localizada na Estação de Tratamento de Esgotos (ETE) Samambaia, em Goiânia, GO. A unidade experimental possui vinte quatro módulos, agrupados em sequências de dois módulos (módulos iniciais e finais). Esgoto sanitário bruto proveniente da parte inicial da lagoa facultativa da ETE foi bombeado no fundo de módulos iniciais de tratamento preenchidos com camadas sobrepostas de substrato (no fundo com brita número 3, na sequência brita número 1, areia lavada e novamente brita número 1) e plantados com taboa ou caniço. Após subir pelo substrato vegetado (fluxo vertical ascendente) o esgoto era drenado e conduzido aos módulos finais de tratamento, igualmente preenchidos e vegetados com uma das espécies, todavia sendo aplicado na superfície e drenado pelo fundo (fluxo vertical descendente). A taxa de aplicação de esgoto foi de 80 L.m-2dia-1, correspondendo a uma área de estação de tratamento de 2 m2 por habitante. Um ano após a implantação do sistema, por um período de seis meses, amostras do esgoto foram coletadas após passar pelas sequências de fluxo, cada uma com uma combinação das duas espécies vegetais, para avaliação dos teores de atributos do esgoto e cálculo da eficiência do tratamento. Os resultados foram analisados pelo programa Statistical Analysis System (SAS), realizando-se os testes F e de Tukey Kramer, a 5% de probabilidade. Não houve diferença significativa entre as eficiências dos tratamentos na remoção dos atributos: demanda bioquímica de oxigênio, demanda química de oxigênio, nitrogênio amoniacal, fosfatos, coliformes termotolerantes, cloretos, dureza, sólidos totais dissolvidos e sólidos totais voláteis. A taboa foi mais eficiente na remoção da cor aparente e da turbidez. Já o caniço apresentou uma eficiência maior na remoção de sólidos totais. A posição da planta na sequência de módulos não influenciou na remoção da cor aparente e da turbidez. O caniço no módulo final influenciou positivamente na remoção dos atributos sólidos totais e sólidos totais fixos. Verifica-se que a tecnologia de tratamento de esgoto por plantas é eficiente, uma vez que as espécies taboa e caniço no sistema de fluxo subsuperficial vertical ora adotado proporcionaram resultados com remoções superiores a 60% para os atributos demanda bioquímica de oxigênio, demanda química de oxigênio, cor aparente, nitrogênio amoniacal, fosfatos, coliformes termotolerantes e turbidez.

O uso de agroquímicos pode causar uma grande variedade de impactos negativos em ambientes aquáticos. Em áreas de exploração agrícola, onde são usados tais produtos, há uma demanda por sistemas de bioremediação que conjuguem baixos custos e simplicidade operacional. Na presente tese são apresentados os resultados da pesquisa que consistiu em se investigar o destino ambiental do agroquímico ametrina quando adicionado a alagados construídos. Foram utilizados sistemas em micro e mesoescala, construídos em Viçosa-MG, que consistiam de macrófitas aquáticas (T. latifolia) plantadas sobre um leito de brita. Para melhor avaliação dos mecanismos nos alagados foi realizado um estudo hidrodinâmico e observou-se que as células operam com boa eficiência hidráulica. No experimento em mesoescala verificou-se a retenção/remoção de 39% da massa de ametrina aplicada, não sendo observadas diferenças significativas entre as 4 unidades utilizadas. No estudo em microcosmo, não foram observadas variações em relação ao teor de nutrientes e a morfo-anatomia das macrófitas. Tal fato pode ser interpretado positivamente, visto que mesmo sob perturbação ambiental a planta adulta conseguiu manter suas características. Como fator a ser considerado, verificou-se que o desenvolvimento inicial da T. latifolia pode ser prejudicado por reduzidas concentrações de ametrina. De uma maneira geral, observou-se que sistemas alagados construídos operando sob escoamento subsuperficial poderão vir a ser usados na mitigação da contaminação de águas por praguicidas. / Pesticides can cause a great spectrum of negative impacts in aquatic environmental. In agricultural lands, these products are largely used and in these regions there is a demand for low costs and simple bioremediation systems. In the present thesis, the results of the research about ametryn environmental fate in subsurface flow constructed wetlands systems are presented. The wetlands cells were built in microcosms and mesocosms scales at Viçosa city, Minas Gerais state. The experimental system was consisted of aquatic macrophytes (T. latifolia) cultivated on a porous gravel bed. A hydrodynamic study was performed for the better knowledge of the mechanisms of pesticide transport. The cells presented good hydraulic efficiency and in mesocosms wetlands were observed that 39% of ametryn amended was removed/retained. No statistical difference among the 4 cells performances was registered. At green house (microcosm) tests, no effects in nutrients and morpho-anatomy were observed. This fact can be interpreted positively, because ever under environmental disturbance, the macrophyte maintained its characteristics. However, aqueous 10-d germination and growth experiment indicate possible ametryn harmful effects to T. latifolia development. In general way, it was observed that vegetated constructed wetlands can be used in depollution of pesticides-contaminated waters.

Precipitation over coal fly ash surfaces raises concerns about potential downstream impacts of dissolved selenium (Se) on aquatic ecosystems. Detention ponds hold runoff until aqueous Se concentrations meet water quality regulations: within 10 days, 90% of runoff must be discharged and cannot exceed 11.8 μg Se L-1 (ppb). Constructed wetland (CW) phytoremediation is a potential treatment option to meet these regulations. This research was conducted to 1.) Assess the potential of native southeastern aquatic macrophytes for Se tolerance and removal efficiency compared to unplanted (UNP) detention ponds; 2.) Evaluate seasonal influence on Se removal in CWs over four, weekly flood-discharge cycles; and 3.) Determine the effect of temperature on aqueous Se removal. Monoculture CW microcosms (110 L) were flooded six days with 500 or 1000 ppb Se, as selenite (SeO32-) or selenate (SeO42-) evaluating five plant species for Se tolerance. Seasonal evaluations were conducted with cattail (Typha angustifolia L.; CAT) and duckweed (Lemna minor L.; DWD) over four weekly flood-discharge cycles at 16 or 32 ppb SeO42--Se. Cattail, DWD, or UNP volatilization chambers (VCs) flooded with a 3 L solution at 35 ppb SeO42--Se were evaluated under 12 h photoperiod at either 20 or 30°C. All experiments contained a zero Se control. Water, plant, and soil total Se concentrations were determined by inductively coupled plasma-mass spectroscopy (ICP-MS) and analyzed with PROC GLM (SAS EG 7.1) at α=0.05. Cattail and DWD were selected for further evaluation with SeO42--Se. The greatest aqueous Se removal was observed in the summer (73%), followed by the fall (42%) and spring (41%), compared to winter (18%). Temperature was strongly correlated with Se removal (0.65, P<0.0001). Except for summer, after two flood-discharge cycles, CAT and DWD improved aqueous Se removal compared to UNP controls. Volatilization chamber data indicated greater Se removal at 30 (69%) compared to 20°C (54%). At 30°C, DWD decreased aqueous Se concentrations below 11.8 ppb Se within 10 days. Given their efficacy and abundance, CAT and DWD are deemed suitable species for phytoremediation in CWs supplied with Se-impacted waters.

Två miljöproblem idag är ökade koncentrationer av växthusgaser i atmosfären och övergödning. Därför är två utmaningar att reducera utsläppen av växthusgaser och flöden av näringsämnen. Ytterligare en utmaning är att trygga energiförsörjningen i en värld där efterfrågan på energi ökar. Nya förnybara energikällor behöver utvecklas både för att trygga energiförsörjningen men även för att minska användandet av fossil energi. En förnybar energikälla är biogas som kan användas till el, värme och fordonsgas. Det förutspås att substrat för biogasproduktion kommer vara en bristvara i framtiden, därför behöver nya substrat utvärderas. Våtmarksväxter är ett alternativt substrat för biogasproduktion och utvärderades i den här studien. Våtmarker och dess växter är intressanta att studera eftersom de kan reducera koncentrationen näringsämnen som når sjöar och hav och kan därför bidra till att minska problemen med övergödning.    Studien genomfördes inom ett projekt vid Biogas Research Center och var en litteraturstudie med studie av ett fall. Metoden som användes har arbetats fram i projektet och är en multikriteriaanalys, (MCA), vilket innebär att det är flera olika områden som studeras. Områdena tar hänsyn till biologiska, ekonomiska, kemiska, miljömässiga och tekniska aspekter. För att strukturera upp informationen användes en matris som bestod av de olika huvudområdena som studerades. För att tydliggöra möjligheter och hinder gjordes en semi-kvalitativ bedömning av varje huvudområde.   Fallet som studerades var en våtmark i odlingslandskapet. Våtmarken är 5 ha och återskapades för några år sedan för att fungera som kväve- och fosforkälla. Det finns ingen växtlighet i våtmarken eftersom den är relativt ny. De växter som studerades under studien var därför växter som är tänkbara att växa i våtmarken i framtiden. Växterna som studerades var vass, rörflen och bredkaveldun. I våtmarken finns möjlighet att reglera vattennivån och därmed tömma den på vatten för att underlätta skörd.   Resultatet visade att den teknik som finns idag för skörd och sönderdelning behöver utvecklas eftersom den inte motsvarar de krav som ställs. Det finns olika tekniker för rötning och eftersom växterna har hög torrsubstanshalt är torrötning att föredra eller ett tvåstegssystem där första steget är torrötning. En våtmark ger en relativt liten mängd biomassa och därför passar det bättre att röta växterna tillsammans med andra substrat till exempel på en gårdsbiogasanläggning.   Våtmarksväxter är inte godkända substrat för certifiering av biogödsel, vilket kan vara ett hinder. Biogödseln har även ett lågt värde eftersom växterna innehåller låg halt näringsämnen. Våtmarker reducerar mängden näringsämnen och skörd kan bidra till att retentionen av fosfor ökar. Samtidigt avger våtmarker metan och lustgas som påverkar växthuseffekten.  Idag finns det ingen ekonomisk lönsamhet att skörda våtmarker. Ett system där ersättning fås för miljönyttan som skörd ger är ett alternativ för att öka lönsamheten. / Two environmental problems today are the increased concentrations of greenhouse gases in the atmosphere and eutrophication.  Therefore, two challenges are reducing greenhouse gas emissions and fluxes of nutrients. Another challenge is to secure the energy supply in a world where energy demand is increasing. New renewable energy sources need to be developed both to secure the energy supply, but also to reduce the use of fossil energy. A renewable energy source is biogas that can be used for electricity, heating and as vehicle fuel. It is predicted that substrate for biogas production will be a limitation in the future, therefore, new substrate need to be evaluated. Wetland plants are an alternative substrate for biogas production and evaluated in this study.  Wetlands and it is plants are interesting to study because they can reduce the concentration of nutrients and therefore help to reduce the problem of eutrophication.  The study was performed within a project at Biogas Research Center and was a literature study with the study of a case. The method used has been developed in the project and is a Multi Criteria Assessment (MCA), which means that there are several different areas being studied. Areas taking into account the biological, economic, chemical, environmental and technological aspects. In order to structure the data, a matrix consisting of the different key areas was used. To clarify the opportunities and obstacles a semi-qualitative assessment was done for each key area. The case studied was a wetland in an agricultural landscape. The wetland is 5 ha and was constructed a few years ago to work as nitrogen and phosphorous trap. There is no vegetation in the wetland because it is relatively new. The plants that were studied during the study was therefore plants that are potential to grow in the wetland in the future. The studied plants were reed, reed canary grass and cattail. In the wetland it is possible to regulate the water and thereby drain the water to facilitate harvesting.   The results showed that the technology available today for the harvesting and chopping needs to be developed because it does not meet the required standards. There are various techniques for digestion, but since the dry matter is high for the plants dry fermentation is preferable, or a two-stage system in which the first step is dry digestion. A wetland provides a relatively small amount of biomass and therefore it is better to co-digest the plants on a farm biogas plant.  Wetland plants are not approved substrates for certification of bio fertilizer, which can be an obstacle. The bio fertilizer also has a low value because the plants contain low levels of nutrients.Wetlands reduce the amount of nutrients and harvest of wetland plants contributes to the retention of phosphorus increases. Wetlands emit methane and nitrous oxide that affect global warming.Today, there is no economic viability of harvesting wetlands. A system in which compensation is obtained for the environmental benefit that harvest provides is an option to increase profitability.

The Everglades is a sub-tropical coastal wetland characterized among others by its hydrological features and deposits of peat. Formation and preservation of organic matter in soils and sediments in this wetland ecosystem is critical for its sustainability and hydrological processes are important divers in the origin, transport and fate of organic matter. With this in mind, organic matter dynamics in the greater Florida Everglades was studied though various organic geochemistry techniques, especially biomarkers, bulk and compound specific δ13C and δD isotope analysis. The main objectives were focused on how different hydrological regimes in this ecosystem control organic matter dynamics, such as the mobilization of particulate organic matter (POM) in freshwater marshes and estuaries, and how organic geochemistry techniques can be applied to reconstruct Everglades paleo-hydrology. For this purpose organic matter in typical vegetation, floc, surface soils, soil cores, and estuarine suspended particulates were characterized in samples selected along hydrological gradients in the Water Conservation Area 3, Shark River Slough and Taylor Slough. This research focused on three general themes: (1) Assessment of the environmental dynamics and source-specific particulate organic carbon export in a mangrove-dominated estuary. (2) Assessment of the origin, transport and fate of organic matter in freshwater marsh. (3) Assessment of historical changes in hydrological conditions in the Everglades (paleo-hydrology) though biomarkes and compound specific isotope analyses. This study reports the first estimate of particulate organic carbon loss from mangrove ecosystems in the Everglades, provides evidence for particulate organic matter transport with regards to the formation of ridge and slough landscapes in the Everglades, and demonstrates the applicability of the combined biomarker and compound-specific stable isotope approach as a means to generate paleohydrological data in wetlands. The data suggests that: (1) Carbon loss from mangrove estuaries is roughly split 50/50 between dissolved and particulate carbon; (2) hydrological remobilization of particulate organic matter from slough to ridge environments may play an important role in the maintenance of the Everglades freshwater landscape; and (3) Historical changes in hydrology have resulted in significant vegetation shifts from historical slough type vegetation to present ridge type vegetation.