Wetlands Research Papers - Academia.edu (original) (raw)

We determined changes of 28 alkanes and 43 different PAHs in 418 wetland soil samples collected on ten sampling trips to three Louisiana estuaries before and after they were oiled from the 2010 Deepwater Horizon disaster. There was a... more

We determined changes of 28 alkanes and 43 different PAHs in 418 wetland soil samples collected on ten sampling trips to three Louisiana estuaries before and after they were oiled from the 2010 Deepwater Horizon disaster. There was a significant decline in 22 of the 28 alkane analytes (0.42% day(-1)), no change in 6, over 2.5 years. The concentration of five aromatic petroleum hydrocarbons (PAHs) increased (range 0.25-0.70% day(-1)), whereas the total PAH pool did not change. Of these five, naphthalene and C-1-naphthalenes are suggested to be of higher toxicity than the other three because of their relatively higher volatility or solubility. The relative proportions of alkane analytes, but not PAHs, does not yet resemble that in the pre-oiled marshes after 3 years, The trajectories of nine indicators for degradation/weathering were either inconclusive or misleading (alkanes) or confirmed the relatively meager degradation of PAHs.

Abstract: Growing demand of land for crop production, commercial cattle rearing, fuel wood, charcoal, construction timber, urbanization and industrialization have resulted in loss of forests in the past. Forests being recognized as an... more

Abstract: Growing demand of land for crop production, commercial cattle rearing, fuel wood, charcoal, construction timber, urbanization and industrialization have resulted in loss of forests in the past. Forests being recognized as an important component of Carbon (C) cycle have gained importance owing to its potential to sequester C.

Constructed wetlands are built to meet a number of regulatory requirements, including compensatory mitigation for wetland losses, treatment of wastewater, and reduction of non-point-source pollution. Natural processes in the wetland... more

Constructed wetlands are built to meet a number of regulatory requirements, including compensatory mitigation for wetland losses, treatment of wastewater, and reduction of non-point-source pollution. Natural processes in the wetland stabilize the substrate, enhance permeability, remove organic, inorganic and microbiological contaminants and facilitate the flux of gases between the sediments and atmosphere. Here we present the results of an ongoing study to evaluate the nutrient retention efficiency of a constructed wetland at the Mansfield Campus of the Ohio State University, built to mitigate the loss of stream and wetlands resulting from the construction of the Riedl Hall in 2005. The wetland is also used for stormwater retention, draining 190,000 m2 of campus uplands. Water samples have been collected monthly since April, 2009 and used for determination of organic and inorganic nutrients. Samples were collected at both the inflow and the outflow. Water temperature, pH, and concentration of total dissolved solids were also measured in situ using portable meters. Although there was considerable variability in the dataset, the mean values for all variables but pH were higher in the inflow compared to the outflow (Total Dissolved Solids = 11% higher; Total Oxidized Nitrogen (NO3 + NO2) = 46% higher; NH4 = 51% higher; PO4 = 122% higher; Total Nitrogen = 37% higher; Total Phosphorus = 43% higher; pH = 1% lower). These downstream changes in the studied variables were attributed primarily to biogeochemical processes in the wetland, which removes excess nutrients and improves water quality. The nutrient removal efficiency of the wetland varied considerably between seasons. Highest nutrient removal was observed during the summer (~40% efficiency), while the lowest was observed in the fall (~25% efficiency). Higher efficiency was observed in the removal of PO4 (65% in summer), while TON had the lowest removal efficiency (22% in the fall). There is a positive significant correlation between precipitation and DIN concentrations in both the inflow and outflow stations. Precipitation events explain 73% of the variability in DIN concentrations on the inflow and 87% of the variability on the outflow. On average, a reduction of 14% in the nutrient removal efficiency of the Riedl wetland was observed after rainfall events.

Les zones humides contemporaines s’inscrivent dans un territoire construit sur la longue durée, résultant d’interactions multiples entre les sociétés et leur environnement, qu’il est nécessaire de comprendre et de contextualiser pour... more

Les zones humides contemporaines s’inscrivent dans un territoire construit sur la longue durée, résultant d’interactions multiples entre les sociétés et leur environnement, qu’il est nécessaire de comprendre et de contextualiser pour mieux saisir les caractéristiques et enjeux des territoires actuels. Par l’approche géo-historique, l’objectif de cet article est de retracer l’évolution sur le temps long des zones humides
de la vallée de l’Escaut, du Moyen Âge à aujourd’hui, à travers l’étude des paléousages, des évolutions morphologiques et des enjeux successifs (pratiques, inondations) qui ont régi ces mutations de longue
durée. Intégrée aux réflexions actuelles, l’étude géo-historique appliquée constitue un outil riche pour les gestionnaires et acteurs de l’environnement afin de mieux circonscrire et gérer les zones humides
d’aujourd’hui, appréhendées en tant que paysages hérités. L’étude diachronique de la métamorphose des zones humides apporte
des éclairages sur les dynamiques contemporaines, la nature des problèmes posés, les enjeux de gestion futurs (préservation,
restauration, valorisation), afin d’établir des prospectives et des projets de territoire en adéquation avec ces héritages et enjeux. Cette démarche entre notamment dans le cadre des processus de labellisation patrimoniale où l’étude géo-historique illustre les « valeurs culturelles et sociales » des zones humides, ici en vue de la candidature au label Ramsar portée par le Parc naturel régional Scarpe-Escaut.

Changes in the status and distribution of Wisconsin's double-crested cormorant (DCCO) breeding population during the 20th century closely approximate a similar pattern throughout the Great Lakes and generally along the Atlantic coast:... more

Changes in the status and distribution of Wisconsin's double-crested cormorant (DCCO) breeding population during the 20th century closely approximate a similar pattern throughout the Great Lakes and generally along the Atlantic coast: a gradual increase in popula- tion size from about 1921 until about 1950, followed by a population crash, and then a remarkable population resurgence beginning in the early

The importance of evapotranspiration (ET), in the hydrological cycle, makes its quantification necessary for agricultural production planning and water resources management in general. Moreover, ET plays a key role in the estimation of... more

The importance of evapotranspiration (ET), in the hydrological cycle, makes its quantification necessary for agricultural production planning and water resources management in general. Moreover, ET plays a key role in the estimation of the soil water balance, either for the detection of water stress conditions, their use as input variable in crop yield models or the study of ecosystem functioning and its relationship to local and regional climate, among others. This research evaluates the ET in the Pool Malebo situated in the Congo River using remote sensing images from different sources (e.g. GLDAS, FEWS NET and MOD16). Monthly global images were collected for the period 2001 to 2016. Furthermore, the ground data points were collected within and outside of the Pool over different land cover. They were used to extract ET values from the collected images. The obtained ET values from each data source and over different land covers are used to identify the effect of the wetland evapotranspiration around the pool for each season during the year. Model results show significant influence of the wetland's ET on the micro climate of the area.

Ramsar convention was approved by Chile in September 1980; and the “Carlos Andwanter Nature Sanctuary”, located in the Cruces River (Lake Region), was designated as the first Ramsar site. Currently there are seven Ramsar sites, all under... more

Ramsar convention was approved by Chile in September 1980; and the “Carlos Andwanter Nature Sanctuary”, located in the Cruces River (Lake Region), was designated as the first Ramsar site. Currently there are seven Ramsar sites, all under the protection regime of national parks, national reserves or nature sanctuaries.
Following the Strategic Plan 1997-1992, Chile established the National Committee on Wetlands, with a national and regional emphasis and with the participation of both governmental and non-governmental organizations. As Focal Points on Communication, Education and Public Awareness (CEPA) on wetlands are two members of the committee, the National Museum of Natural History and the Union of Chilean Ornithologists (governmental and non-governmental organizations respectively).
Both organizations are working on CEPA, together and independently of each other, and their activities are directed to general public, students (junior and high schools, and universities) and also include public authorities. The National Museum of Natural History developed specific materials (CD ROM, booklet, and poster) to give to regional and local authorities, information on wetlands, Ramsar convention, and national and international legal aspects involved in wetland conservation and management.
We discuss the spatial and temporal success of these activities and also the difficulties we found to reach the goals. The activities dedicated to communication with public authorities are very important, because there are several decisions taken at local level (regions, provinces and counties) and related with wetlands; but also a central (governmental) support is needed. In the educational system, the wetlands are treated as part of the “environment issue” and still have to be specifically included in different levels of education.

Multiple disturbances to ecosystems can influence community structure by modifying resistance to and recovery from invasion by non-native species. Predicting how invasibility responds to multiple anthropogenic impacts is particularly... more

Multiple disturbances to ecosystems can influence community structure by modifying resistance to and recovery from invasion by non-native species. Predicting how invasibility responds to multiple anthropogenic impacts is particularly challenging due to the variety of potential stressors and complex responses. Using manipulative field experiments, we examined the relative impact of perturbations that primarily change abiotic or biotic factors to promote invasion in coastal salt marsh plant communities. Specifically we test the hypotheses that nitrogen enrichment and human trampling facilitate invasion of upland weeds into salt marsh, and that the ability of salt marsh communities to resist and/or recover from invasion is modified by hydrological conditions. Nitrogen enrichment affected invasion of non-native upland plants at only one of six sites, and increased aboveground native marsh biomass at only two sites. Percent cover of native marsh plants declined with trampling at all sites, but recovered earlier at tidally flushed sites than at tidally restricted sites. Synergistic interactions between trampling and restricting tidal flow resulted in significantly higher cover of non-native upland plants in trampled plots at tidally restricted sites. Percent cover of non-native plants recovered to pre-trampling levels in fully tidal sites, but remained higher in tidally restricted sites after 22 months. Thus, perturbations that reduce biotic resistance interact with perturbations that alter abiotic conditions to promote invasion. This suggests that to effectively conserve or restore native biodiversity in altered systems, one must consider impacts of multiple human disturbances, and the interactions between them.

Butterflies, bees, parasites