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1.
Water Res ; 168: 115139, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31605832

RESUMO

Glyphosate is the most widely-used pesticide for weed control in agriculture and in urban and residential areas. This is the first study to quantify glyphosate and AMPA levels in surface water in Australia from different land uses. Glyphosate and AMPA was measured in surface water from 10 rural streams, 30 urban stormwater wetlands and 9 urban streams located in and around the city of Melbourne, Australia on five occasions between October 2017 and February 2018. Glyphosate and AMPA were present in most of the urban surface water samples. The frequency of detection of glyphosate was 77% in wetlands and 79% in urban streams, whereas it was only detected in 4% of the rural streams. Similarly, AMPA detection was 91% in wetlands and 97% in urban streams, whereas it was only present in 6% of the rural stream samples. In both urban streams and wetlands, the highest average glyphosate concentrations occurred in November (1.8 ±â€¯2.2 µg L-1). Overall, wetlands and streams associated with urban land use are vulnerable to glyphosate contamination. These results highlight the importance of screening for contaminants in urban stormwater to identify the source of pollutants that may end up in aquatic ecosystems and the risks therefrom.


Assuntos
Herbicidas , Poluentes Químicos da Água , Austrália , Cidades , Ecossistema , Monitoramento Ambiental , Glicina/análogos & derivados , Isoxazóis , Rios , Tetrazóis , Áreas Alagadas
2.
Water Res ; 168: 115154, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31630020

RESUMO

Pyrrhotite is often considered as a gangue mineral, and discarded in mine wastes and tailings. Glyphosate and fertilizer, often excessively used in agriculture, flow into water bodies with agriculture runoff, and cause pollution of water bodies. In this study, the pyrrhotite was used as a substrate in a pilot constructed wetland (CW) to remove the glyphosate and nutrients from simulated agriculture runoff. In nearly one year, the pilot pyrrhotite constructed wetland (Pyrr-CW) removed 90.3 ±â€¯6.1% of glyphosate, 88.2 ±â€¯5.1 of total phosphorus (TP) and 60.40 ±â€¯5.60% of total nitrogen (TN) on average, much higher than the control CW. The abundances of sulfur-oxidizing bacteria, such as Sulfurifustis, Sulfuriferula and Thiobacillus, were much higher in the Pyrr-CW than those in the control CW. In the Pyrr-CW goethite was produced by pyrrhotite aerobic oxidation (PAO) and pyrrhotite autotrophic denitrification (PAD) continuously and spontaneously. Higher glyphosate and TP removals were resulted from adsorption on the goethite produced, and higher TN removal was attributed to the PAD. High glyphosate and nutrients removal could keep a long term until the pyrrhotite in the Pyrr-CW was used up. The phosphorus (P) sequestered in the Pyrr-CW existed mainly in organic P, (Fe + Al)P and (Ca + Mg)P, and their order was (Fe + Al)P > organic P > (Ca + Mg)P. No heavy metal ions released from the Pyrr-CW. With higher and lasting removal rate, and lower cost, the Pyrr-CW is a promising technology for simultaneous glyphosate and nutrients removal from agricultural runoff and wastewater.


Assuntos
Nutrientes , Áreas Alagadas , Agricultura , Glicina/análogos & derivados , Nitrogênio , Fósforo , Eliminação de Resíduos Líquidos , Águas Residuárias
3.
Water Res ; 168: 115153, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655441

RESUMO

A suite of biomarkers, including amino acids, pigments, and lignin phenols coupled with high resolution mass spectrometry were used to evaluate differences in the sources and fate of organic matter (OM) in Everglades treatment wetlands as a model for OM cycling in shallow water wetlands. Five components of the system (water column particulate matter, vertical traps, flocculent material, periphyton, and surface soil) were assessed for OM transformations down-profile (i.e. water column to soil) and between treatment cells dominated by emergent aquatic vegetation (EAV) and submerged aquatic vegetation (SAV), with comparisons to reference sites within the remnant Everglades. We found that OM cycling is fundamentally different between EAV and SAV wetlands, and that SAV wetlands have some shared characteristics with similar habitats in the remnant Everglades. Other than locations densely populated by Typha spp., water column particulate organic C was predominantly derived from microbial/cryptomonad sources, rather than macroscopic sources (vascular plants and algal mats). Bacterial amino acid biomarkers were positively correlated with amino acid degradation indices and organic P (Po), respectively suggesting that microbial abundance is associated with less degraded OM, and that further investigation into relationships between microbial biomass and Po is warranted. Overall, this multi-biomarker approach can elucidate the relative degradation of OM pools, identify sources of OM, and highlight the importance of water column processes in shallow water wetlands.


Assuntos
Purificação da Água , Áreas Alagadas , Biomarcadores , Plantas , Solo
4.
Water Sci Technol ; 80(3): 466-477, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596258

RESUMO

Wetlands are among the most productive ecosystems that provide services ranging from flood control to climate change mitigation. Wetlands are also critical habitats for the survival of numerous plant and animal species. In this study, we used satellite remote sensing techniques for classification and change detection at an internationally important wetland (Ramsar Site) in Turkey. Sultan Marshes is located at the center of semi-arid Develi closed basin. The wetlands have undergone significant changes since the 1980s due to changes in water flow regimes, but changes in recent years have not been sufficiently explored yet. In this study, we focused on the changes from 2005 to 2012. Two multispectral ASTER images with spatial resolution of 15 m, acquired on June 11, 2005 and May 20, 2012, were used in the analyses. After geometric correction, the images were classified into four information classes, namely water, marsh, agriculture, and steppe. The applicability of three classification methods (i.e. maximum likelihood (MLH), multi-layer perceptron type artificial neural networks (ANN) and support vector machines (SVM)) was assessed. The differences in classification accuracies were evaluated by the McNemar's test. The changes in the Sultan Marshes were determined by the post classification comparison method using the most accurate classified images. The results showed that the highest overall accuracy in image classifications was achieved with the SVM method. It was observed that marshes and steppe areas decreased while water and agricultural areas expanded from 2005 to 2012. These changes could be the results of water transfers to the marshes from neighboring watershed.


Assuntos
Monitoramento Ambiental/métodos , Máquina de Vetores de Suporte , Áreas Alagadas , Conservação dos Recursos Naturais , Ecossistema , Eugenol , Redes Neurais (Computação) , Turquia , Óxido de Zinco
5.
Water Sci Technol ; 80(3): 597-606, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596270

RESUMO

Despite recent developments in process-based modeling of treatment wetlands (TW), the dynamic response of horizontal flow (HF) aerated wetlands to interruptions of aeration has not yet been modeled. In this study, the dynamic response of organic carbon and nitrogen removal to interruptions of aeration in an HF aerated wetland was investigated using a recently-developed numerical process-based model. Model calibration and validation were achieved using previously obtained data from pilot-scale experiments. Setting initial concentrations for anaerobic bacteria to high values (≈ 35-70 mg L-1) and including ammonia sorption was important to simulate the treatment performance of the experimental wetland in transition phases when aeration was switched off and on again. Even though steady-state air flow rate impacted steady-state soluble chemical oxygen demand (CODs), ammonia nitrogen (NH4-N) and oxidized nitrogen (NOx-N) concentration length profiles, it did not substantially affect corresponding effluent concentrations during aeration interruption. When comparing simulated with experimental results, it is most likely that extending the model to include mass transfer through the biofilm will allow to better explain the underlying experiments and to increase simulation accuracy. This study provides insights into the dynamic behavior of HF aerated wetlands and discusses assumptions and limitations of the modeling approach.


Assuntos
Carbono/análise , Nitrogênio/análise , Eliminação de Resíduos Líquidos , Poluição da Água/estatística & dados numéricos , Áreas Alagadas , Análise da Demanda Biológica de Oxigênio , Desnitrificação
6.
Bioresour Technol ; 294: 122189, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31569043

RESUMO

In this study, various modified agricultural wastes (modified canna leaves (MCL), modified rice straw (MRS) and modified peanut shells (MPS)) as solid carbon sources (SCSs) were used to remove nitrate in constructed wetlands (CWs). Then, modified SCSs combined with nZVI (SCSN) as co-electrons further enhanced both heterotrophic denitrification (HD) and autotrophic denitrification (AD) performance of CWs. The results showed that NO3--N removal efficiencies in CWs with SCSNs (75.3-91.1%) and in CWs with SCSs (63.3-65.5%) were significantly higher than that in CK-CW (47.0%). The presence of SCSs reduced the accumulation of NO2--N in CWs. Compared to the addition of SCSs, the addition of SCSNs decreased the effluent COD concentration in CWs, avoiding secondary pollution. In addition, the solid-phase denitrifiers Silanimonas and Thauera were enriched in MPS-CW. Thermomonas, an autotrophic denitrifying bacteria (ADB), and Azospira, a nitrate-reducing Fe (II) oxidation bacteria (NRFOB), exhibited high relative abundance in MPN-CW.


Assuntos
Desnitrificação , Áreas Alagadas , Adsorção , Carbono , Nitratos , Nitrogênio
7.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3518-3526, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621239

RESUMO

To explore the effects of Spartina alterniflora invasion in a seaward direction on variations of inorganic sulfur forms in marsh soils, the levels of inorganic sulfur forms (H2O-S, Adsorbed-S, HCl-Soluble-S and HCl-Volatile-S) were determined in bare flat (BF, before invasion), S. alterniflora marsh after seaward invasion for one year (SA') and S. alterniflora marsh after seaward invasion for three years (SA) in Shanyutan of the Minjiang River estuary with the method of space-for-time substitution. Results showed that the seaward invasion of S. alterniflora altered the stocks and distribution of inorganic sulfur form in marsh soils. Compared with BF, the contents of H2O-S, Adsorbed-S and HCl-Volatile-S in soils of SA increased by 52.6%, 78.2% and 21.0%, respectively, while that of HCl-Soluble-S decreased by 3.4%. In contrast, the levels of H2O-S, Adsorbed-S and HCl-Soluble-S in soils of SA' increased by 43.9%, 70.6% and 29.6%, respectively, whereas that of HCl-Volatile-S decreased by 11.6%. The contents of total inorganic sulfur (TIS) in soils of SA and SA' increased by 40.7% and 37.8%, while the stocks of TIS increased by 26.8% and 31.4%, respectively. The key factors affecting different forms of inorganic sulfur in marsh soils had changed due to the seaward invasion of S. alterniflora. In particular, the key factors affecting the variations of H2O-S contents changed from soil grain composition and bulk density in BF to soil organic matter in SA' and SA. The seaward invasion of S. alterniflora significantly increased the content of TIS in marsh soils, which was mainly contributed by H2O-S and Adsorbed-S. Thus, it was concluded that the seaward invasion of S. alterniflora significantly increased the supply capacity of available sulfur in marsh soils, which, to some extent, accelerated its seaward invasion.


Assuntos
Solo , Áreas Alagadas , China , Estuários , Espécies Introduzidas , Poaceae , Rios , Enxofre
8.
J Environ Manage ; 252: 109664, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31610450

RESUMO

Degradation of wetland ecosystems has negatively impacted many species, perhaps none more so than marsh birds that breed in vegetative emergent wetlands throughout North America. The U.S. Department of Defense manages approximately 29 million acres of land within the continental U.S., and many military installations contain wetland complexes that may be important for wetland birds. Thus, failure to adequately manage habitat for marsh birds could result in species extirpations and additional listings under the Endangered Species Act, and may result in regulatory burdens that reduce military readiness. We conducted spatial analyses to identify important breeding habitat on > 500 military installations for 12 species of marsh birds, with the goal of identifying installations that are, and are not, likely to harbor breeding habitat for each species. We also sought to assess the local value of military installations for species of greatest concern by comparing habitat suitability within installations to that in areas directly adjacent to those sites. We built range-wide, spatially-explicit models of species distribution to project suitability of breeding habitat for marsh birds within and adjacent to military installations. Our results demonstrate that installations with the best marsh bird habitat are geographically aggregated (both among and within species), primarily at sites along the eastern seaboard and within the southern U.S. In addition, only a few sites appear to contain high-quality habitat for most species. Five or fewer sites contained most of the high-quality habitat for 9 of 12 species, whereas most of the high-quality habitat for remaining species was found at ≤ 10 sites. This work fills an information gap regarding the distribution of breeding habitat for marsh birds on military lands across the U.S., and should facilitate both strategic conservation of habitat over broad scales and the integration of marsh birds into management efforts at the site level. Our analyses also identify installations that are not likely to harbor breeding habitat for priority species, and thus should help minimize conflicts between needs of the military and marsh-bird conservation.


Assuntos
Militares , Áreas Alagadas , Animais , Aves , Cruzamento , Conservação dos Recursos Naturais , Ecossistema , Humanos , América do Norte
9.
J Environ Manage ; 252: 109499, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31627098

RESUMO

The synthesis of emergy and eco-exergy is one of the most effective methods in the evaluation of wetland restoration. In this study, the landscape design for the restoration of Napahai wetland in the northwest Yunnan Plateau of China was carried out, and the sustainability and self-organizational level of the wetland before and after restoration were evaluated using eco-exergy and emergy combined with the Lorenz curve method. The results showed that wetland plants rapidly increased from 26 species to 52 species after two years, with a gradual decrease in pollutant-enduring species and the reappearance of the marsh plants Sparganium simplex and Batrachium bungei communities that had disappeared for many years, which speed up the succession and structure organization of the community. The wetland was better for biomass accumulation and soil improvement after restoration, and there were significant decreases in the concentrations of TP, TN and COD in the water body. The sustainability index values for the wetland ranged from 4.17 before restoration to 2385.16 after restoration, and the ecosystem service values for the wetland after restoration was 1.95 times higher than that before restoration. These results confirmed that the wetland after restoration was less environmentally stressed and more sustainable. In addition, the values of eco-exergy and specific eco-exergy after restoration were 1.70 and 1.01 times higher than that before restoration, respectively; the emergy/exergy ratio was lower for the wetland after restoration. These results suggested that the wetland after restoration had higher complexity and self-organizational level, and became a self-sustaining and resilient natural system. This study represents a new exploration of the emergy and eco-exergy evaluation on the wetland restoration, providing an engineering demonstration and a reference for the landscape design of wetland restoration in the plateau region.


Assuntos
Ecossistema , Áreas Alagadas , Biomassa , China , Conservação dos Recursos Naturais , Solo
10.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(3): 307-310, 2019 Jul 26.
Artigo em Chinês | MEDLINE | ID: mdl-31544414

RESUMO

OBJECTIVE: To investigate the epidemic factors of schistosomiasis in wetlands in Sichuan Province, so as to provide scientific evidence for the prevention and control of schistosomiasis in wetlands. METHODS: The artificial and natural wetlands were selected from Sichuan Province, and the relevant data regarding wetlands were collected. Routine snail survey, investigation on human morbidity due to schistosomiasis, snail diffusion experiments, questionnaire survey, determination of water infectivity and retrospective survey were conducted. RESULTS: In Sichuan Province, the mean densities of living snails were 0.003 snails/0.1 m2 and 2.033 snails/0.1 m2 in the upper and lower reaches of the Meiwan Reservoir wetlands, 0.08 snails/0.1 m2 in the Jinyan Lake of Guanghan City, 0.21 snails/0.1 m2 in Muhe River of Guanghan City, and 0.02 snails/0.1 m2 prior to the construction of Qiong-hai wetland park in Xichang City in 2015. Artificial simulation experiments showed that the largest distance of snail diffusion in water was 2 000 m. There were 8.80% (41/466) of subjects that lived neighboring wetlands, worked in wetlands and visited wet-lands having infested water contact behaviors. A total of 690 sentinel mice were assigned, and no Schistosoma japonicum infection was detected in the 677 mice dissected. Retrospective survey showed that the construction of the Meiwan Reservoir caused the spread of schistosomiasis in Dailing County, and snails were found in the ditches entering the Jinyan Lake and in Jinyan Lake areas 5 years following the construction of the Jinyan Lake in Guanghan City, with S. japonicum -infected snails detected in the ditches entering the Jinyan Lake. CONCLUSIONS: O. hupensis snails are found in some wetlands in Sichuan Province. Protection of wetlands and snail control with environmental improvements are recommended for the prevention of snail importation in natural wetlands, while in artificial wetlands, thorough snail control is recommended during the construction of the wetlands because of the likelihood of snail importation via water systems. In addition, both natural and artificial wetlands require long-term systematic surveillance of schistosomiasis.


Assuntos
Esquistossomose , Áreas Alagadas , Distribuição Animal , Animais , China/epidemiologia , Conservação dos Recursos Naturais , Humanos , Camundongos , Densidade Demográfica , Estudos Retrospectivos , Fatores de Risco , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Espécies Sentinelas/parasitologia , Caramujos/parasitologia
11.
Bioresour Technol ; 293: 122003, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31476567

RESUMO

Aquaculture wastewater seriously threatens the human health. In this study, non-poisonous iron was added into constructed wetlands to purify aquaculture wastewater and the wastewater treatment performances of CWs were explored under the treatment conditions of different plant species and different dosages of ferrous ions. The optimal treatment conditions were experimentally determined as follows: 20 mg/L ferrous ions in CWs planted with Canna indica after 7-day operation, the removal efficiencies of TN, TP and COD were respectively 95 ±â€¯1.9%, 77 ±â€¯1.2% and 62 ±â€¯2%. The improvements in the pollutant removal performance depended on biological mechanisms of plants and microorganisms. The optimal dosage of iron ions could adjust enzyme activities and functional amino acids. Specific functional bacteria (Paracoccus detected based on nirK genetic information and Hydrogenophaga detected based on pufM genetic information) were cultured and domesticated by iron ions. The functional bacteria promoted nitrogen and phosphorus removals.


Assuntos
Poluentes Ambientais , Águas Residuárias , Aquicultura , Ferro , Nitrogênio , Eliminação de Resíduos Líquidos , Áreas Alagadas
12.
Bioresour Technol ; 293: 122086, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31495460

RESUMO

Constructed wetland (CW) for wastewater treatment has attracted increasing attention. In this review, the system configuration optimization, purification effect and general mechanisms of nitrogen removal in CW are systematically summarized and discussed. Ammonia oxidation is a crucial and primary process for total nitrogen (TN) removal in domestic or livestock wastewater treatment. Aeration, waterdrop influent and tidal operation are three main methods to strengthen the oxygen supplement and nitrification process in CW. Aeration significantly increases the ammonia removal rate (almost 100%), followed by the removal of chemical oxygen demand (COD) and TN. Solid carbon source, iron and anode material can be filled as electron donor for the denitrification process. The co-adjustment of oxygen and carbon/electron donor can form different conditions for different nitrogen removal pathways (e.g. the simultaneous nitrification-denitrification, the partial nitrification-denitrification and the anammox process), and achieve the optimal removal of nitrogen.


Assuntos
Águas Residuárias , Áreas Alagadas , Desnitrificação , Nitrificação , Nitrogênio
13.
Water Sci Technol ; 80(2): 254-264, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31537761

RESUMO

The research developed a combined system in batch flow and in pilot scale for the treatment and reuse of urban effluents. The system was fed raw effluent from a university campus in Brazil and composed of four anaerobic reactors, three constructed wetlands (CWs) and an ozonation unit. The three sequential hybrid constructed wetlands were composed of a floating treatment wetland, an aerobic-anoxic baffled constructed wetland (CW) and a saturated vertifcal flow CW. Later, during the last trimester, weekly samples of the treated effluent were ozonated by bubbling with an application rate of 240 mg.h-1 O3. The system presented high removal rates efficiencies in terms of carbonaceous organic matter (78.9%), nitrogen (91.0%), color (96.7%) and turbidity (99.1%). In addition, it worked well for disinfection and acute ecotoxicity, but P was only efficiently (75%) removed in the first 8 months, with removing efficiency declining after this period. Ozonation provided significant color removal and an increased pH. The combination of floating, alternated upflow and downflow and saturated vertical flows improved the treatment of wastewater. This was due to the presence of both aerobic and anaerobic zones, as well as the filter substrate, through an integrated system with simple construction and operation and increased lifespan.


Assuntos
Ozônio , Eliminação de Resíduos Líquidos , Águas Residuárias , Áreas Alagadas , Anaerobiose , Brasil
14.
Water Sci Technol ; 80(2): 265-273, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31537762

RESUMO

The main approach for designing vertical flow (VF) treatment wetlands is based on areal requirements ranging from 2 to 4 m2 per person equivalent (PE). Other design parameters are the granularity of the filter material, filter depth, hydraulic and organic loading rates, loading intervals, amount of single doses as well as the number of openings in the distribution pipes. The influence of these parameters is investigated by running simulations using the HYDRUS Wetland Module for three VF wetlands with different granularity of the filter material (0.06-4 mm, 1-4 mm, and 4-8 mm, respectively). For each VF wetland, simulations are carried out at different temperatures for different organic loading rates, loading intervals and number of distribution points. Using coarser filter material results in reduced removal of pollutants and higher effluent concentrations if VF wetlands are operated under the same conditions. However, the treatment efficiency can be increased by applying more loadings and/or a higher density of the distribution network. For finer filter material, longer loading intervals are suggested to guarantee sufficient aeration of the VF filter between successive loadings.


Assuntos
Eliminação de Resíduos Líquidos , Áreas Alagadas
15.
Water Sci Technol ; 80(2): 347-356, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31537771

RESUMO

Utilization of the French system of vertical wetlands for treating raw sewage keeps increasing, but there is still limited consolidated information on their long term use in tropical countries. Under these conditions, there are indications that surface area requirements can decrease, whilst still keeping a satisfactory performance. However, variations in the operational mode and the role of the surface organic deposit layer under warm climatic conditions have not been fully investigated. The goal of this work was to evaluate the performance of a system comprised of only the first stage of the French system, with a further reduction of 1/3 of the area (utilization of only two units in parallel, instead of three) in terms of organic matter removal and nitrogen conversion, with one unit with a deposit layer accumulated over 9 years of operation, and the other unit without sludge layer, under Brazilian tropical conditions. The system was originally designed according to Cemagref/Irstea recommendations for the first-stage of the French system for the treatment of raw sewage generated by an equivalent population of 100 inhabitants. However, it was later on changed, and operated with only two units, using only 0.6 m2·pe-1. Feeding and resting periods were of 7 days each. In order to evaluate the influence of the sludge layer, the top sludge from one of the units was removed, and the performance of both units was compared by the Mann-Whitney test. The database comprises the wetland performance values in terms of dissolved oxygen (DO), redox potential (Eh), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total suspended solids (TSS), total Kjeldahl nitrogen (TKN), NH4+-N and NO3+-N, covering a monitoring period of 15 months. The effluent DO concentrations were significantly lower in the unit with top sludge, but still sufficiently high in both units. Although there were some variations between both units, effluent concentrations of the major pollutants were not significantly different in the units with and without sludge, and removal efficiencies based on mean values were considered good, given the reduced area of the system: BOD (80% and 79%), TSS (85% and 82%), TKN (60% and 63%) for the units with and without sludge, respectively. Under Brazilian climatic conditions, with the reduced area and employing longer feeding cycles (7 days), the sludge accumulation rate (less than 1 cm·year-1) was lower compared to the French mean values.


Assuntos
Eliminação de Resíduos Líquidos , Áreas Alagadas , Análise da Demanda Biológica de Oxigênio , Brasil , Esgotos
16.
Water Environ Res ; 91(10): 1378-1389, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31529659

RESUMO

This article presents an update on the research and practical demonstration of wetland treatment technologies for wastewater treatment. Applications of wetlands in wastewater treatment (as an advanced treatment unit or a decentralized system) and stormwater management or treatment for nutrient and pollutant removal (metals, industrial and emerging pollutants including pharmaceutical compounds and pathogens) are highlighted. A summary of studies involving the effects of vegetation, wetland design and operation, and configurations for efficient treatment of various municipal and industrial wastewaters is also included. PRACTITIONER POINTS: Provides an update on current research and development of wetland technologies for wastewater treatment. Effects of vegetation, pathogens removal, heavy metals and emerging pollutants removal are included. Wetland design and operation is a key factor to improve water quality of wetland effluent.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Eliminação de Resíduos Líquidos , Águas Residuárias , Qualidade da Água , Áreas Alagadas
17.
An Acad Bras Cienc ; 91(3): e20180924, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31531534

RESUMO

The authors of the 19th century had demonstrated the viviparity of the species Rhizophora mangle L. with the formation of propagules in the form of spears devoid a radicle, adapted self-planting in the soil of the mangrove or to leave floating in vertical during the high tide. With low tide the propagules self-planting or remain prostrate on the soil but later become upright later. When the seedlings are unearthed, those who are self-planting are straight from end to end; those that stood erect later show a curvature at the base in the form of J (J-shaped). Authors of the last 30 years have questioned the self-planting and accurately demonstrate how the prostrate propagules rise from the ground. It has been verified that the propagule is stem from end to end and does not present radicle, that is, under the plumale there is the hypocotyls without a root. All roots are adventitious, agreeing with 19th century researchers, not lateral roots as researchers of the present century have claimed. Propagules that return to the beach in Porto Seguro (BA) probably of another flowering period show an extra growth of the lower part, but this growth remains a stem rather than a root, demonstrating that there is no root, as 19th century researchers claimed.


Assuntos
Rhizophoraceae/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Avicennia , Brasil , Germinação , Rhizophoraceae/citologia , Rhizophoraceae/fisiologia , Plântula/citologia , Plântula/fisiologia , Solo , Áreas Alagadas
18.
J Environ Manage ; 250: 109439, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31499461

RESUMO

Ecosystem restoration is gaining political and economic support worldwide, but its exact targets and costs often remain unclear. A key issue, both for predicting restoration success and assessing the costs, is the uncertainty of post-restoration development of the ecosystem. A specific combination of uncertainties emerges when ecosystem restoration would negatively affect pre-restoration species conservation values. Such dilemma appears to be common, but largely ignored in restoration planning; for example, in historically degraded forests, wetlands and grasslands that provide novel habitats for some threatened species. We present a framework of linked options for resolving the dilemma, and exemplify its application in extensive mire restoration in Estonia. The broad options include: redistributing the risks by timing; relocating restoration sites; modifying restoration techniques; and managing for future habitats of the species involved. In Estonia, we assessed these options based on spatially explicit mapping of expected future states of the ecosystem, their uncertainty, and the distribution of species at risk. Such planning documentation, combined with follow-up monitoring and experimentation, can be used for adaptive management, by funding organizations and for academic research.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Espécies em Perigo de Extinção , Estônia , Áreas Alagadas
19.
J Environ Manage ; 250: 109409, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31521033

RESUMO

The purpose of this study was to analyze the rate of sporulation, richness, and spore diversity of dematiaceous and Ingoldian fungi colonizing Typha latifolia leaves during a 40-day period of decomposition, as well as the loss of mass in Typha latifolia, in four riverine wetlands of Pampean plain (Argentina) with different water quality. Higher sporulation rates, richness, and diversity of the fungi as well as loss of mass of the leaves that they colonized were associated with lower water quality. Anguilospora longissima, Arthrinium sp., Margaritispora aquatica, and Tricellula botryosa were dominant taxa. Redundancy analysis showed two fungal assemblages related to different environmental conditions. One assemblage was related to higher nutrient levels and higher temperature, characterized mainly by dematiaceous fungi. The other assemblage was related to higher levels of pH and dissolved oxygen, which was mainly represented by Ingoldian fungi. The results obtained in our study demonstrated the link between these fungal assemblages and changes in water quality, revealing their potential as indicators of environmental changes in rivers exposed to different types of land use.


Assuntos
Typhaceae , Argentina , Biodegradação Ambiental , Fungos , Folhas de Planta , Qualidade da Água , Áreas Alagadas
20.
J Environ Manage ; 250: 109491, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31521034

RESUMO

Carbon source and influent COD/N (chemical oxygen demand: total nitrogen) pose distinct effects on nitrogen removal efficiency and microbial community structure of constructed wetlands. To investigate the interactive effect of carbon source with COD/N on nitrogen removal and microbial community structure in subsurface flow constructed wetlands, glucose (C6H12O6) and sodium acetate (C2H3NaO2) were used to determine five COD/N ratios in nine groups of constructed wetlands divided into glucose constructed wetlands and sodium acetate constructed wetlands. Results showed that efficiency in COD removal increased with COD/N, and peak value reached 92.7%. Interactive effect of carbon source with COD/N on system pH and ammonium removal was notably significant. Differences in ammonium removal performance between treatments were achieved by the variation of influent COD/N ratio and the change of system pH resulted from different carbon sources, and the result suggested that glucose was a better choice at high COD/N ratio. System microbial community structure was significantly affected by carbon source, influent COD/N ratio and their interaction. Microbial biomass in constructed wetlands significantly increased with increasing COD/N ratio. Higher density and diversity of fungus were observed in glucose constructed wetlands, particularly at COD/N ratio of 7 and 10.


Assuntos
Microbiota , Áreas Alagadas , Análise da Demanda Biológica de Oxigênio , Carbono , Desnitrificação , Nitrogênio
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