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The increasing loss of wetlands at the global scale demands immediate response by improving management practices and ecological restoration. When people degrade wetlands, environmental restoration must overcome biotic and economic barriers that can be considerable. We assessed the floristic composition of a wetland subjected to anthropic disturbances and expansion of invasive species, then compared our results with historical data from 2005 to 2015. The result revealed that changes in floristic composition and dominant native and invasive dominant species occurred during this 16-year period. In the dry season, we found significant differences in species richness between the years 2005 and 2021, with a significant reduction in species richness in the latter year. This loss of species richness represents an unfavorable change in the floristic composition trajectory, which we explain as an effect of sustained anthropic disturbance. Floristic data from the rainy season was not conclusive. Typha domingensis , and the invasives Phragmites australis and Festuca arundinacea have been favored by disturbances and increased their cover at the expense of other wetland species, reducing the wetland's floristic diversity. Our objective was to redirect the floristic composition trajectory in the La Mintzita wetland by proposing management strategies for controlling the above-mentioned species based on three ecological restoration strategies: biocultural (targeting simultaneously the loss of biodiversity and of traditional use of Typha), productive (to control expansion of P. australis which has no traditional use in the region, we propose a new use), and ecocentric (to control F. arundinacea and recover native species cover). [ABSTRACT FROM AUTHOR]

Constructed or treatment wetlands (CWs) are a sustainable option to clean wastewater in the face of water pollution problems. Consequently, this study was aimed at reviewing and analyzing the use of CWs in Mexico. This involved types, sizes, and functionality in the removal of pollutants, as well as the main plant species that are used. Furthermore, 67 studies regarding CWs were found, which were classified according to the treatment area as microcosms, mesocosms, pilot scale, and full-scale at 18, 30, 25, and 27%, respectively. The most used types of CWs are those of subsurface flow (87%) versus free-water surface (13%), of which horizontal flow direction (58%) are the most common. Considering Full-Scale CWs, the pollutant removal reported for COD, BOD5, TN, and TP oscillated between 50–90%, 60–90%, 30–90%, and 30–70%, respectively. Among the vegetation that is more used for Mexican CWs, 78 different species were detected; Typha and Cyperus hydrophytes species and ornamental flowering plants as Zantedeschia aethiopica., Canna genus., Heliconia genus, Hedychium coronarium, and Anturium andreanum species (plants with commercial value) were the most used plants. It was concluded that although there is an important advance in the use of ecotechnology as it is an attractive answer for decentralized wastewater treatment in Mexico, results revealed the need to migrate towards the use of CWs in full-scale size, in order to address real pollution problems. Thus, the further implementation of CWs in rural and urban regions with similar tropical and subtropical characteristics as in Mexico is suggested by the authors. [ABSTRACT FROM AUTHOR]

This study explores the cultural, economic, and ecosystem impacts of an invasive plant species, southern cattail (Typha domingensis), on the indigenous Purépecha community of Lake Pátzcuaro, Mexico. Locally known as chuspatel , the species inhabits the same lacustrine space as the native southern bulrush (Schoenoplectus californicus), known locally as tule. In order to control the species, southern cattail is routinely mechanically harvested in parts of the lake. Southern bulrush, on the other hand, is native to the lake, has similar ecological characteristics as southern cattail, and has long been used by indigenous crafts persons. Our initial goal was to explore the distribution and possible negative effects of an invasive plant on a culturally important native wetland plant species. Data collection included open ended interviews, participant observation, and GIS-based vegetation mapping of the two species. Contrary to expectations, our results revealed several cultural, economic, and possibly ecosystem service benefits associated with the arrival and spread of this invasive organism. Cartographic data show that the two species overlap in distribution in the lake. Observations suggest that the invasive species may provide an additional ecosystem service of enhanced habitat for an endemic snake subspecies (Thamnophis eques patzcuaroensis). Moreover, rather than displacing a culturally useful native species, the invasive southern cattail has been incorporated into the repertoire of local crafts and now represents an important addition to the income and culture of the Purépecha. Our study suggests that greater management emphasis should be placed on local and cultural values when considering the overall impacts of invasive organisms. [ABSTRACT FROM AUTHOR]

Featured Application: This study describes the importance of the use of ornamental flowering plants in constructed wetlands as wastewater treatment systems, as well as highlighting which species have been tested in terms of their ability to adapt and remove contaminants so that they can be used in new designs of domiciliary, rural and urban wetlands, generating better water cleaning, aesthetic landscape and economic potential. The vegetation in constructed wetlands (CWs) plays an important role in wastewater treatment. Popularly, the common emergent plants in CWs have been vegetation of natural wetlands. However, there are ornamental flowering plants that have some physiological characteristics similar to the plants of natural wetlands that can stimulate the removal of pollutants in wastewater treatments; such importance in CWs is described here. A literature survey of 87 CWs from 21 countries showed that the four most commonly used flowering ornamental vegetation genera were Canna, Iris, Heliconia and Zantedeschia. In terms of geographical location, Canna spp. is commonly found in Asia, Zantedeschia spp. is frequent in Mexico (a country in North America), Iris is most commonly used in Asia, Europe and North America, and species of the Heliconia genus are commonly used in Asia and parts of the Americas (Mexico, Central and South America). This review also compares the use of ornamental plants versus natural wetland plants and systems without plants for removing pollutants (organic matter, nitrogen, nitrogen and phosphorous compounds). The removal efficiency was similar between flowering ornamental and natural wetland plants. However, pollutant removal was better when using ornamental plants than in unplanted CWs. The use of ornamental flowering plants in CWs is an excellent option, and efforts should be made to increase the adoption of these system types and use them in domiciliary, rural and urban areas. [ABSTRACT FROM AUTHOR]

Distillery wastewater (DWW) is a highly polluted industrial effluent generated during the distillation step for the production of alcohol from some feedstocks such as sugarcane, corn, sugar beet, wheat, agave, etc. The aim of this review was to find out the current use of constructed wetlands (CWs) for DWW treatment and/or the challenges of using this technology for such effluent. It was found that CWs has been evaluated almost exclusively at laboratory and pilot-scale levels for DWW produced from sugarcane/agave for alcohol or alcoholic beverage production. India, Brazil and Mexico are the main countries where CWs have been studied for DWW treatment with anaerobic digestion, dilution with tap water and cooling-sedimentation-neutralization pretreatments. Chemical Oxygen Demand (COD) concentration in the reported studies varied from 1181 to 14,055 mg/L and organic loading rate (OLR), between 61.2 and 281 g COD/d.m2. The highest removal efficiencies were 95% - 96% in two types of conventional CWs treating DWW generated during an alcoholic beverage production in Mexico. It was found that the higher the hydraulic retention time (HRT), the higher the efficiency for COD removal. According to this review, it is possible to use CWs for the treatment of DWW with high removal efficiencies of pollutants such as COD, with high HRT in deeper systems (to avoid a greater surface area), coarse filter material and an adequate selection of plants. [Display omitted] • DWW is produced during alcohol production. • DWW is a highly polluted industrial effluent. • India, Brazil and Mexico and other countries have evaluated CWs for DWW treatment. • CWs are used for the treatment of DWW with previous pretreatment. • Removal of COD can be as high as 96% with an influent concentration of 14 g/L. [ABSTRACT FROM AUTHOR]

Abstract: Greenhouse and field trials were conducted to determine the salinity limits for main vegetation types in Cienega de Santa Clara, an oligohaline marsh in the delta of the Colorado River in Mexico. The Cienega is the largest brackish marsh in the Sonoran Desert and supports numerous bird, mammal and invertebrate species, including threatened or endangered marsh birds. It is supported by brackish agricultural return flows from the USA and Mexico, and operation of the Yuma Desalting Plant (YDP) could reduce the volume and increase the salinity of inflows. Current inflows average 4m3 s−1 at 2.8gL−1 Total Dissolved Solids (TDS), and the dominant vegetation type is Typha domingensis, with subdominant stands of Schoenoplectus americanus and other emergent species distributed amidst the Typha stands. A greenhouse experiment showed that under flooded-soil conditions, T. domingensis had a linear reduction in relative growth rate based on biomass production (RGRBiomass) with salinity, with zero RGRBiomass at 8.3gL−1 TDS and a 50% reduction at 4.0gL−1 TDS. S. americanus was about twice as salt-tolerant, with zero RGRBiomass at 12.5gL−1 TDS and 50% RGRBiomass at 9gL−1 TDS. The results are consistent with other studies that show a mean reduction in RGRBiomass of 13.3% per g L−1 TDS for Typha spp. and 4.3% per g L−1 TDS for Schoenoplectus spp. Field surveys showed that T. domingensis stands were restricted to salinities of 6.5gL−1 TDS or less, and that annual biomass production was reduced by 85% in a stand at 5.9gL−1 TDS compared to a stand at 3.0gL−1 TDS. Normalized Difference Vegetation Index (NDVI) values of T. domingensis stands from satellite imagery showed a linear decline with increasing salinity in the marsh. It was concluded that 6gL−1 TDS is the approximate upper limit for vigorous stands of T. domingensis, and that replacement by S. americanus is a possibility if salinities increase. Implications for marsh vegetation structure and habitat value are discussed under different possible operating scenarios for the YDP. [Copyright &y& Elsevier]

Abstract: The Ciénega of Santa Clara is a valuable coastal wetland sustained almost entirely by discharge of brackish agricultural drain water from the U.S. and Mexico. In other locations, agricultural drain water has been problematic in supporting wetlands due to problems of salinity buildup, toxic substances and undesirable plant succession processes. We studied the development of the Cienega de Santa Clara from its creation in 1977 to the present to determine if it is on a sustainable trajectory in terms of vegetation, hydrology and habitat value. We used Landsat NDVI imagery from 1975 to 2011 to determine the area and intensity of vegetation and to estimate evapotranspiration (ET) to construct a water balance. Remote sensing data were combined with hydrological data, site surveys and other sources of information on the Cienega. The vegetated area increased from 1978 to 1995 and has been constant at about 4200ha 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 NDVIMax. Flows into the marsh have been stable both month-to-month and year-to-year, with a mean annual value of 4.74m3 s−1 (SD=1.03). Salinity has been stable with a mean value of 2.09gL−1 TDS (SD=0.13). About 37% 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. The sustainability of the Cienega is attributed to: stable inflow rates; salinities within the tolerance limit of the dominant vegetation; and tidal flushing which maintains the wetland as an open system. [Copyright &y& Elsevier]

Abstract: Salinity has affected the Colorado River for more than five decades: agriculture, mining and urban sprawl have exacerbated the problem, with the most severe impacts occurring in its southern basin and Mexico. However, moderate salinities (2.6gL−1 Total Dissolved Solids) and constant average flows (4m3 s−1) from a U.S. agriculture drain, have allowed the establishment of a 6500ha cattail (Typha domingensis) dominated wetland in the mudflats of the upper Gulf of California in Mexico, called “Cienega de Santa Clara” (Cienega). This wetland could now be threatened due to the operation of the Yuma Desalting Plant (YDP). Operations will result in reduced flows and salinity increases in the canal that feeds the wetland. From 2006 to 2011 we monitored water quality conditions at the Cienega as part of a binational effort. Monthly monitoring of field parameters was made at the inflows and at 28 stations inside the wetland. In 2010, 4 automatic loggers were installed inside the wetland to take half an hour readings of temperature and salinity. At the center of the Cienega from 70 to 80% of salinity variations depended on salinity from the main inflow; this response was observed with both monthly data and daily data, indicating a rapid response from salinity inflows. The YDP demonstration run at 10% capacity caused a mean salinity increase from 3.0 to 3.3gL−1 TDS at the center of the wetland and from 3.8 to 5.2gL−1 TDS salinity increase at the periphery. During the YDP pilot run at one-third capacity, mean salinity increased from 3.2 to 4.3gL−1 TDS at the center of the wetland and from 4.3 to 8.3gL−1 TDS at the periphery. There was no evidence of upper Gulf of California tidal intrusion into the wetland. Salinity concentrations at the main inflow should not exceed 3.0gL−1 TDS in order to prevent a reduction in cattail growth inside the wetland. Nevertheless, our recommendation is to maintain salinities at 2.6±0.2gL−1 TDS at the main inflow, in order to preserve vigorous cattail stands. Operation of the YDP plant at 10%, one-third, two-thirds and full capacity without replacement water, will have negative effects on the vegetation. Future efforts should be oriented to compensate for possible salinity increases. [Copyright &y& Elsevier]

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This paper analyzes the sustainability of organizations engaged in the exploitation of Thypha spp. cattail in the Zapotlán Lagoon and its impact on socio-economic and environmental development of the municipal districts of Gómez Farías and Zapotlán the Great. The initial working hypothesis is delimited by the consideration that the low social capital of organizations engaged in the exploitation of cattail in the Zapotlán Lagoon limits the sustainability of development, although it contributes to income support for more than 300 families in San Sebastian and to a lesser degree in Ciudad Guzman. The method used is ethnographic research, supplemented by field work supported by informal interviews and documental and literature research. The main conclusion is that there is not a balance between the sustainability of the organizations due to the low social capital and the sustainability of environmental and economic development that should be considered by the rehabilitation program of the Zapotlán lagoon regarding the improvement of income levels, recovery and creation of new jobs and improvement of standards of quality of life of about three hundred families dependent on cultivation and artisanal exploitation of cattail. In order to give greater sustainability to micro and small artisanal enterprises, the creation of an export consultancy program for artisanal products derived from cattail to the effect of increasing the value added that provides the proper management of marketing processes in international markets. [ABSTRACT FROM AUTHOR]

The influence of local actors and socioeconomic constraints on biological invasions is often ignored. Wetland plant harvesters appeared to intentionally influence cattail ( Typha domingensis) invasion around Lake Pátzcuaro, México, by altering their harvesting regimes, according to interviews with 44 expert respondents and botanical surveys. The oldest and most experienced harvesters reported controlling Typha initially, sometimes through organized eradication efforts, in order to protect Schoenoplectus californicus, an economically and culturally valuable wetland plant. Later, outsiders commoditized Typha by introducing new weaving designs popular with tourists, while industrial products and new livelihood activities reduced Schoenoplectus harvest. Harvesters from several communities began to promote Typha re-growth. Some harvesters, however, continued to combat Typha to maintain Schoenoplectus production, especially where supply was limited. Interviews suggested novel ecological cause–effect mechanisms and restoration strategies; some local harvesting regimes could efficiently conserve rare plants. An understanding of local ecological knowledge and incentives can inform invasive species control and conservation policy at a broader scale. [ABSTRACT FROM AUTHOR]

Copyright of Universidad & Ciencia is the property of Universidad Juarez Autonoma de Tabasco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)