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In this study, the effect of Spathiphyllum blandum on the removal of ibuprofen (IB) and conventional pollutants such as chemical oxygen demand (COD), total nitrogen (TN), ammonium (NH 4 -N), total phosphorus (TP), and total suspended solids (TSS) is reported; this, through its use as an emergent vegetation in fully saturated (FS) constructed wetlands (CWs) at mesocosm level treating polluted river water. With the exception of TP and COD, it was found that for TN (12%), NH + -N), total phosphorus (TP), and total suspended solids (TSS) is reported; this, through its use as an emergent vegetation in fully saturated (FS) constructed wetlands (CWs) at mesocosm level treating polluted river water. With the exception of TP and COD, it was found that for TN (12%), NH 4 + -N (11%), TSS (19%), and IB (23%), the removals in systems with vegetation were superior to systems without vegetation (p < 0.05). These findings demonstrate the importance of the species S. blandum, in particular, for the removal of ibuprofen, which is an anti-inflammatory drug commonly found in effluents of wastewater treatment plants. Thus, the results obtained provide information that can be used for the design of future efficient large-scale systems using a new ornamental species, mainly under tropical climatic conditions.

Vertical partially saturated (VPS) constructed wetlands (CWs) are a novel wastewater treatment system for which little information is known about its design parameters and performance under tropical climates. The objective of this study is to evaluate the nitrogen removal process from domestic wastewater and the production of tropical ornamental plants ( Canna hybrids and Zantedeschia aethiopica ) in VPS CWs at a mesocosms scale. Nine VPS CWs, with a free-flow zone of 16 cm and a saturated zone of 16 cm, were used as experimental units. Three units were planted with Canna hybrids., and three, with Zantedeschia aethiopica (one plant per unit); the remaining three units were established as controls without vegetation. They were fed with domestic wastewater intermittently and evaluated for the elimination of COD, N-NH 4 , N-NO 3 , Norg, NT, and PT. The results showed an increase in the removal for some pollutants in the vegetated systems, i.e., N-NH 4 (35%), Norg (16%), TN (25%), and TP (47%) in comparison to the unvegetated systems. While N-NO 3 removal showed better removal in 10% of the systems without vegetation, no significant differences were found ( p > 0.05) for COD removal. The aerobic and anaerobic conditions in the VPS CWs favor the elimination of pollutants in the systems, and also the development of the tropical species evaluated in this study; good development was exhibited by a high growth rate and biomass production.

This study reports a literature review of the state of the art, 2000-2020, on the substrates that are used as support media in constructed wetlands with subsurface flow. Its importance compared to the most used substrates worldwide and its economic feasibility as a substrate in CW. 13 different types of substrates have been identified in 155 different studies, but the most used substrates were gravel (32%) and sand (23%) for the development of bacterial associations. However, gravel and sand used in full-scale CW are expensive (10–35 $USD/m3), for wastewater treatment in small communities with economic difficulties. The tendency is to use substrates such as gravel (32%), sand (23%), sediments (13%), limestone or river rock (11%), granite (8%), zeolite (6%) and other alternative materials (7%). Among these we can mention: ceramics, pumice, steel, bricks, shells of different local aquatic fauna and some stone materials easily found in the study area. Therefore, the development of substrates of lower commercial value, reused material and material of easy operation is important, especially in developing countries where economic resources are one of the main constraints in the implementation of wastewater treatment systems. The use of treatment wetlands with economic materials detected in this study indicate that the future in wastewater treatment is this technology, because present multiple objectives, which include water treatment, fertilizer production, enhancement of biodiversity and cooling, vegetation production for handicraft, etc. CW are a technology with future role in circular economy that want to respond to sanitation worldwide. [ABSTRACT FROM AUTHOR]

Despite occupying an area no greater than 8% of the earth's surface, natural wetland ecosystems fulfill multiple ecological functions: 1. Soil formation and stabilization support, 2. Food, water, and plant biomass supply, 3. Cultural/recreational services, landscape, and ecological tourism, 4. Climate regulation, and 5. Carbon sequestration; with the last one being its most important function. They are subject to direct and indirect incident factors that affect plant productivity and the sequestration of carbon from the soil. Thus, the objective of this review was to identify the incident factors in the loss of area and carbon sequestration in marine, coastal, and continental wetlands that have had an impact on climate change in the last 14 years, globally. The methodology consisted of conducting a literature review in international databases, analyzing a sample of 134 research studies from 37 countries, organized in tables and figures supported by descriptive statistics and content analysis. Global results indicate that agriculture (25%), urbanization (16.8%), aquaculture (10.7%), and industry (7.6%) are incident factors that promote wetlands effective loss affecting continental wetlands more than coastal and marine ones. Regarding carbon sequestration, this is reduced by vegetation loss since GHG emissions raise because the soil is exposed to sun rays, increasing surface temperature and oxidation, and raising organic matter decomposition and the eutrophication phenomenon caused by the previous incident factors that generate wastewater rich in nutrients in their different activities, thus creating biomass and plant growth imbalances, either at the foliage or root levels and altering the accumulation of organic matter and carbon. It is possible to affirm in conclusion that the most affected types of wetlands are: mangroves (25.7%), lagoons (19.11%), and marine waters (11.7%). Furthermore, it was identified that agriculture has a greater incidence in the loss of wetlands, followed by urbanization and industry in a lower percentage. [ABSTRACT FROM AUTHOR]

Improving water quality is a relevant environmental aspect, and using constructed wetlands (CWs) is a sustainable option for this; both porous material filled cells and plants that collectively remove contaminants must be readily available and inexpensive. This study evaluated CWs and their functionality by comparing two ornamental plants (Spathiphyllum wallisii and Hedychium coronarium) planted in experimental mesocosm units filled with layers of porous river rock, tepezil, and soil, or in mesocosms with layers of porous river rock, and tepezil, without the presence of soil. The findings during the experiments (180 days), showed that the removal of pollutants (chemical oxygen demand (COD), total solids suspended (TSS), nitrogen as ammonium (N-NH4), as nitrate (N-NO3), and phosphate (P-PO4) was 20–50% higher in mesocosms with vegetation that in the absence of this, and those mesocosms with the soil layer between 33–45% favored removal of P-PO4. Differences regarding of vegetation removal were only observed for N-NH4, being 25–45% higher in CWs with H. coronarium, compared with S. wallisii. Both species are suitable for using in CWs, for its functionality as phytoremediation, and aesthetic advantages could generate interest for wastewater treatment in rural communities, parks, schools or in domiciliary levels like floral flower boxes in the backyard. The study also revealed that a soil layer in CWs is necessary to increase the removal of P-PO4, an ion hardly eliminated in water treatment. [ABSTRACT FROM AUTHOR]