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1

Wetland vegetation establishment in L-Lake  

SciTech Connect

Wetland vegetation was transplanted from PAR Pond to L-Lake between January and August, 1987. Approximately 100,000 individual plants representing over 40 species were transplanted along the southern shoreline. Three zones of vegetation were created: (1) submersed/floating-leaved, (2) emergent, (3) upper emergent/shrub. During the summers of 1987, 1988, 1989, the Savannah River Ecology Laboratory sampled the vegetation in 54 permanent transects located in planted (N=32) and unplanted areas (N=22). The 1989 vegetation data from L-Lake were compared to 1985 data from PAR Pond.

Kroeger, S.R.

1990-07-01

2

Establishment of vegetation in constructed wetlands using biosolids and quarry fines  

SciTech Connect

A common problem with constructing wetlands on abandoned mine sties is the lack of adequate soil needed to establish vegetation. One component of a full-scale passive treatment system built at Jennings Environmental Education Center in Brady Township, Butler County, PA addressed this issue through the development of a field trial to find an inexpensive alternative substrate for wetland plants. A simple soil recipe was followed which called for the mixing of an inorganic material with a nutrient-rich organic material. The inorganic constituent used was silt-size pond cleanings from a sand and gravel operation. The organic material used was a composted product made from exceptional-quality biosolids. Both soil components were obtained from local sources (less than 16 kilometers (12 miles) from the site) and mixed on site with a Caterpillar 963 track loader. The soil was used to construct a channel wetland 3 meters (10 feet) wide by 61 meters (200 feet) long. A seed mixture which contained 24 different wetland plant species native to western Pennsylvania was added to the substrate prior to releasing the water from the vertical flow system into the wetland. After one year, the vegetation was studied to determine the percent cover and species composition in order to document the effectiveness of this method of wetland construction. The preliminary results of this study indicate that this is an effective means to establish and sustain wetland vegetation. The addition of a fabricated substrate consisting of composted biosolids and silt can be a very effective method to establish dense and diverse vegetation in a constructed wetland.

Danehy, T.P.; Zick, R.; Brenner, F.; Chmielewski, J.; Dunn, M.H.; Cooper, D.C.

1999-07-01

3

Upland and wetland vegetation establishment on coal slurry in northern Missouri  

SciTech Connect

Since the Cooperative Wildlife Research Laboratory`s (CWRL) Mined Land Reclamation Program`s first establishment of a wetland on slurry in 1976, industry, state, and federal agency interest in reclamation alternatives for inactive slurry has increased. CWRL has been involved in pre-reclamation site characterization and monitoring for inactive slurry impoundments throughout Illinois, Indiana, Kansas, Kentucky, Missouri, and Washington. Geochemical site characterization of three slurry impoundments at the AECI Bee Veer Mine located near Macon, Missouri began in April 1990. A substrate sampling grid was established for all slurry impoundments with a centerline orientated parallel to the discharge to decant flow pattern. Surface (0--6 in.) and subsurface (30--36 in.) slurry samples were collected annually and analyzed for acid-base balance, immediate acidity macro- and micro-nutrients, potential phytotoxic metallic ions and salts, and texture. Water table elevations and water quality were monitored quarterly from shallow ({le}12 ft.) piezometers. General reclamation plans included annual (3 years) incremental limestone amendments (35--50 tons/acre) and direct vegetation establishment. Cool and warm season grasses dominate vegetation cover in upland habitats (slurry cell RDA1) while wetland habitats (palustrine emergent seasonally-permanently inundated) have been established in slurry cells (RDA2 and RDA3). Isolated hot spots continue to be amended with limestone and supplemental vegetation establishment is scheduled.

Skeel, V.A.; Nawrot, J.R. [Southern Illinois Univ., Carbondale, IL (United States). Cooperative Wildlife Research Lab.

1998-12-31

4

Establishment and Evaluation of the Vegetative Community in A Surface Flow Constructed Wetland Treating Industrial Park Contaminants  

Microsoft Academic Search

A surface flow constructed wetland, designed to curve in a kidney shape in order to increase the length to width ratio to 5:1 was used to treat runoff from an industrial park. A natural wetland system located approximately 200 m downstream of the constructed wetland was selected to act as the vegetative community model for the constructed wetland. The selected

C. C. Galbrand; A. M. Snow; A. E. Ghaly; R. Côté

2008-01-01

5

Vegetation establishment and evolution in four ponds that received sewage and wastewater in a portion of the Olezoa wetland complex, Yaounde, Cameroon, central Africa  

SciTech Connect

A study of the spatial and temporal changes in the pattern and distribution of tropical wetland vegetation in four ponds that received sewage and wastewater discharge, was undertaken for a small wetland ecosystem in the Olezoa drainage basin in Yaounde, Cameroon. More than 25 years of nutrient loading has led to the eutrophication and subsequent establishment of wetland vegetation in these ponds. Estimated free water surface areas of the ponds in 1964, 1976, and 1986 and 1992 determined from digitized aerial photographs and field measurements suggests a decline of 70 to 100% in the pond surface areas due to invasion and colonization by plants. The rate of pond surface decline and vegetation development is correlated with the construction of sewage plants and the discharge of untreated sewage and wastewater into the ponds. The main wetland plants that are established in the ponds consist of aquatic species Nymphae lotus, Enhydra fluctuants, Pistia stratiotes, Commelina sp., Ipomea aquatica and terrestrial species Echinochloa sp., Thalia welwitschii, Polygonum senegalense, Leersia haxandra and Cyperus papyrus. The pattern of wetland plant succession that resulted within each pond is correlated to the timing, duration and magnitude of sewage and wastewater discharge into the wetland complex.

Atekwana, E.A. (Western Michigan Univ., Kalamazoo, MI (United States). Dept. of Geology); Agendia, P.L. (Univ. of Yaounde (Cameroon). Dept. of Plant Biology)

1994-04-01

6

Contribution of Seed Banks to Freshwater Wetland Vegetation Recovery  

Microsoft Academic Search

Recovery of freshwater wetlands after oil spills depends on removal or degradation of the oil and regeneration of the plant community. To quantify the importance of seed banks to re- establishment of vegetation, soil cores (N = 210) were extracted from a freshwater wetland near Dulac, LA and exposed to sweet or sour crude oil, diesel fuel, or tap water.

MILAN C. VAVREK; WILLIAM J. CAMPBELL

7

Disturbance metrics predict a wetland Vegetation Index of Biotic Integrity  

USGS Publications Warehouse

Indices of biological integrity of wetlands based on vascular plants (VIBIs) have been developed in many areas in the USA. Knowledge of the best predictors of VIBIs would enable management agencies to make better decisions regarding mitigation site selection and performance monitoring criteria. We use a novel statistical technique to develop predictive models for an established index of wetland vegetation integrity (Ohio VIBI), using as independent variables 20 indices and metrics of habitat quality, wetland disturbance, and buffer area land use from 149 wetlands in Ohio, USA. For emergent and forest wetlands, predictive models explained 61% and 54% of the variability, respectively, in Ohio VIBI scores. In both cases the most important predictor of Ohio VIBI score was a metric that assessed habitat alteration and development in the wetland. Of secondary importance as a predictor was a metric that assessed microtopography, interspersion, and quality of vegetation communities in the wetland. Metrics and indices assessing disturbance and land use of the buffer area were generally poor predictors of Ohio VIBI scores. Our results suggest that vegetation integrity of emergent and forest wetlands could be most directly enhanced by minimizing substrate and habitat disturbance within the wetland. Such efforts could include reducing or eliminating any practices that disturb the soil profile, such as nutrient enrichment from adjacent farm land, mowing, grazing, or cutting or removing woody plants.

Stapanian, Martin A.; Mack, John; Adams, Jean V.; Gara, Brian; Micacchion, Mick

2013-01-01

8

Effects of Woody Vegetation on Prairie Wetland Birds  

Microsoft Academic Search

Bird surveys were conducted in wetlands (n = 1(00) throughout South Dakota during the summers of 1995 and 1996 to assess effects of woody vegetation encroachment on nongame wetland bird species. Wetland bird species richness decreased as the extent of woody vegetation encompassing wttland perimeters increa.o;ed. Logistic analyses indicated that four wetland bird species (Black Tern (Chlidonills niger). Wilson's Phalarope

DAVID E. NAUGLE; KENNETH F. HIGGlNs; SARAH M. NUSSER

9

Does prescribed fire benefit wetland vegetation?  

USGS Publications Warehouse

The effects of fire on wetland vegetation in the mid-Atlantic region of the United States are poorly known, despite the historical use of fire by federal, state, and private landowners in the Chesapeake Bay Region. Prescribed fire is widely used by land managers to promote vegetation that is beneficial to migratory waterfowl, muskrats, and other native wildlife and to reduce competition from less desirable plant species. We compared vegetative response to two fire rotations, annual burns and 3-year burns, and two control sites, Control 1 and Control 2. We tested the effects of fire within six tidal marsh wetlands at Blackwater National Wildlife Refuge and Fishing Bay Wildlife Management Area in Maryland. We examined changes in total live biomass (all species), total stem density, litter, and changes in live biomass and stem density of four dominant wetland plant species (11 variables). Our results suggest that annual prescribed fires will decrease the accumulation of litter, increase the biomass and stem densities of some wetland plants generally considered less desirable for wildlife, and have little or no effect on other wetland plants previously thought to benefit from fire. ?? 2011 US Government.

Flores, C.; Bounds, D.L.; Ruby, D.E.

2011-01-01

10

Vegetative Nutrient Pools in a Constructed Wetland in Southeastern Idaho  

Microsoft Academic Search

We examined the vegetative pools of carbon (C), nitrogen (N), and phosphorus (P) in constructed wetlands receiving irrigation return flows in southeastern Idaho. Seven native wetland plant species were introduced into the wetlands in 1999. Carex nebrascensis, Eleocharis palustris, Juncus balticus, and Scheonoplectus maritimus were planted in replicate wetland meadows (primary filters), and Scheonoplectus acutus, Scheonoplectus pungens, and Typha latifolia

Andrew M. Ray; Richard S. Inouye

2006-01-01

11

Vegetation of Upper Coastal Plain depression wetlands: Environmental templates and wetland dynamics within a landscape framework.  

SciTech Connect

Reference wetlands play an important role in efforts to protect wetlands and assess wetland condition. Because wetland vegetation integrates the influence of many ecological factors, a useful reference system would identify natural vegetation types and include models relating vegetation to important regional geomorphic, hydrologic, and geochemical properties. Across the U.S. Atlantic Coastal Plain, depression wetlands are a major hydrogeomorphic class with diverse characteristics. For 57 functional depression wetlands in the Upper Coastal Plain of South Carolina, we characterized the principal vegetation types and used a landscape framework to assess how local (wetland-level) factors and regional landscape settings potentially influence vegetation composition and dynamics. Wetland sites were stratified across three Upper Coastal Plain landscape settings that differ in soils, surface geology, topography, and land use. We sampled plant composition, measured relevant local variables, and analyzed historical transitions in vegetative cover types. Cluster analysis identified six vegetation types, ranging from open-water ponds and emergent marshes to closed forests. Significant vegetation-environment relationships suggested environmental ''templates'' for plant community development. Of all local factors examined, wetland hydrologic regime was most strongly correlated with vegetation type, but depression size, soil textural type, and disturbance history were also significant. Because hydrogeologic settings influence wetland features, local factors important to vegetation were partly predictable from landscape setting, and thus wetland types were distributed non-randomly across landscape settings. Analysis of long-term vegetation change indicated relative stability in some wetlands and succession in others. We developed a landscape-contingent model for vegetation dynamics, with hydroperiod and fire as major driving variables. The wetland classification, environmental templates, and dynamics model provide a reference framework to guide conservation priorities and suggest possible outcomes of restoration or management.

De Steven, Diane; Toner, Maureen, M.

2004-03-01

12

Effects of dominant species on vegetation change in Carolina bay wetlands following a multi-year drought.  

SciTech Connect

Wetland vegetation is strongly dependent upon climate-influenced hydrologic conditions, and plant composition responds in generally consistent ways to droughts. However, the extent of species composition change during drought may be influenced by the pre-existing structure of wetland vegetation. We characterized the vegetation of ten herbaceous Carolina bay wetlands on the South Carolina Upper Coastal Plain during a period of average rainfall and again near the end of a four-year drought. We hypothesized that, as a group, bays dominated by less robust plant species (characteristic of open-water pond and depression meadow vegetation types) would show greater compositional change than bays dominated by dense, robust-form clonal graminoids (characteristic of grass and sedge marsh vegetation types). Aquatic species decreased during the drought in all wetlands, regardless of vegetation group. Compared to grass/sedge marshes, pond/meadow wetlands acquired more species, particularly non-wetland species, during the drought. Pond/meadow wetlands also had greater increases in the abundances of species that require unflooded conditions to establish. Prior to the drought, all wetlands were ponded almost continuously, but during drought the pond/meadow wetlands had shorter and more variable hydroperiods than the grass/sedge marshes. Thus, vegetation change may be partly confounded with hydrologic conditions that provide greater opportunities for species recruitment in pond/meadow bays. The results suggest that Carolina bay vegetation dynamics may differ as a function of dominant vegetation and climate driven variation in wetland hydrologic condition.

Mulhouse, John, M.; De Steven, Diane; Lide, Robert, F.; Sharitz, Rebecca, R.

2005-05-01

13

Vegetation survey of PEN Branch wetlands  

SciTech Connect

A survey was conducted of vegetation along Pen Branch Creek at Savannah River Site (SRS) in support of K-Reactor restart. Plants were identified to species by overstory, understory, shrub, and groundcover strata. Abundance was also characterized and richness and diversity calculated. Based on woody species basal area, the Pen Branch delta was the most impacted, followed by the sections between the reactor and the delta. Species richness for shrub and groundcover strata were also lowest in the delta. No endangered plant species were found. Three upland pine areas were also sampled. In support of K Reactor restart, this report summarizes a study of the wetland vegetation along Pen Branch. Reactor effluent enters Indian Grove Branch and then flows into Pen Branch and the Pen Branch Delta.

Not Available

1991-01-01

14

Correspondence between vegetation and soils in wetlands and nearby uplands  

USGS Publications Warehouse

The association between vegetation and soils from a geographically broad sampling of wetlands and adjoining uplands is reported for 38 hydric and 26 nonhydric soils, as recognized in the hydric soils list of the Soil Conservation Service. Wetlands represented in the study include estuaries, pitcher plant bogs, prairie depressional wetlands, and western riparian lands. The agreement between vegetation and soils is clear with few exceptions. In general, hydric soils support hydrophytic plant communities, and nonhydric soils support upland communities. Only 10% of the hydric soils sampled support upland communities and only 15% of the nonhydric soils support wetland communities. Exceptions to the correspondence between vegetation and soils are discussed; local hydrology, the transitional nature of some soils, and other determinants of wetland vegetation structure (e.g., salinity, disturbance) seem to account for many of the observed discrepancies. A method that simplifies the complexity of soils and vegetation cannot be expected to represent accurately all details of their interrelations.

Scott, Michael L.; Slauson, William L.; Segelquist, Charles A.; Auble, Gregor T.

1989-01-01

15

Vegetation and environmental conditions in recently restored wetlands in the prairie pothole region of the USA  

Microsoft Academic Search

How closely the vegetation of restored wetlands resembles that of comparable natural wetlands is a function of the probability of propagules of wetland species reaching reflooded wetlands and how similar environmental conditions in the restored wetland are those in the natural wetlands. Three years after reflooding, we examined the vegetation composition, water level fluctuations, soil organic carbon content, and soil

Susan M. Galatowitsch; Arnold G. van der Valk

1996-01-01

16

Changes in the Vegetation Cover in a Constructed Wetland at Argonne National Laboratory, Illinois  

SciTech Connect

Wetlands are valuable resources that are disappearing at an alarming rate. Land development has resulted in the destruction of wetlands for approximately 200 years. To combat this destruction, the federal government passed legislation that requires no net loss of wetlands. The United States Army Corps of Engineers (USACE) is responsible for regulating wetland disturbances. In 1991, the USACE determined that the construction of the Advanced Photon Source at Argonne National Laboratory would damage three wetlands that had a total area of one acre. Argonne was required to create a wetland of equal acreage to replace the damaged wetlands. For the first five years after this wetland was created (1992-1996), the frequency of plant species, relative cover, and water depth was closely monitored. The wetland was not monitored again until 2002. In 2003, the vegetation cover data were again collected with a similar methodology to previous years. The plant species were sampled using quadrats at randomly selected locations along transects throughout the wetland. The fifty sampling locations were monitored once in June and percent cover of each of the plant species was determined for each plot. Furthermore, the extent of standing water in the wetland was measured. In 2003, 21 species of plants were found and identified. Eleven species dominated the wetland, among which were reed canary grass (Phalaris arundinacea), crown vetch (Coronilla varia), and Canada thistle (Cirsium arvense). These species are all non-native, invasive species. In the previous year, 30 species were found in the same wetland. The common species varied from the 2002 study but still had these non-native species in common. Reed canary grass and Canada thistle both increased by more than 100% from 2002. Unfortunately, the non-native species may be contributing to the loss of biodiversity in the wetland. In the future, control measures should be taken to ensure the establishment of more desired native species.

Bergman, C.L.; LaGory, K.

2004-01-01

17

A spatial simulation model of hydrology and vegetation dynamics in semi-permanent prairie wetlands  

USGS Publications Warehouse

The objective of this study was to construct a spatial simulation model of the vegetation dynamics in semi-permanent prairie wetlands. A hydrologic submodel estimated water levels based on precipitation, runoff, and potential evapotranspiration. A vegetation submodel calculated the amount and distribution of emergent cover and open water using a geographic information system. The response of vegetation to water-level changes was based on seed bank composition, seedling recruitment and establishment, and plant survivorship. The model was developed and tested using data from the Cottonwood Lake study site in North Dakota. Data from semi-permanent wetland P1 were used to calibrate the model. Data from a second wetland, P4, were used to evaluate model performance. Simulation results were compared with actual water data from 1797 through 1989. Test results showed that differences between calculated and observed water levels were within 10 cm 75% of the time. Open water over the past decade ranged from 0 to 7% in wetland P4 and from 0 to 8% in submodel simulations. Several model parameters including evapotranspiration and timing of seedling germination could be improved with more complex techniques or relatively minor adjustments. Despite these differences the model adequately represented vegetation dynamics of prairie wetlands and can be used to examine wetland response to natural or human-induced climate change.

Poiani, Karen A.; Johnson, W. Carter

1993-01-01

18

[Estimating total nitrogen content in wetland vegetation based on measured reflectance spectra].  

PubMed

More and more urban wetlands have been supplied with reclaimed water. And monitoring the growth condition of large-area wetland vegetation is playing a very important role in wetland restoration and reconstruction. Recently, remote sensing technology has become an important tool for vegetation growth monitoring. The South Wetland in the Olympic Park, a typical wetland using reused water, was selected as the research area. The leaf reflectance spectra and were acquired for the main wetland plants reed (Phragmites australis) and cattail (Typha angustifolia) with an ASD FieldSpec 3 spectrometer (350 2 500 nm). The total nitrogen (TN) content of leaf samples was determined by Kjeldahl method subsequently. The research established univariate models involving simple ratio spectral index (SR) model and normalized difference spectral index (ND) model, as well as multivariate models including stepwise multiple linear regression (SMLR) model and partial least squares regression (PLSR) model. Moreover, the accuracy of all the models was tested through cross-validated coefficient of determination (R2(CV)) and cross-validated root mean square error (RMSE(CV)). The results showed that (1) comparing different types of wetland plants, the accuracy of all established prediction models using Phragmites australis reflectance spectra was higher than that using Typha angustifolia reflectance spectra. (2) compared with univariate techniques, multivariate regressions improved the estimation of TN concentration in leaves. (3) among the various investigated models, the accuracy of PLSR model was the highest (R2(CV) = 0.80, RMSE(CV) = 0.24). PLSR provided the most useful explorative tool for unraveling the relationship between spectral reflectance and TN consistence of leaves. The result would not only provide a scientific basis for remote sensing retrieval of biochemical variables of wetland vegetation, but also provide a strong scientific basis for the monitoring and management of urban wetlands using recycled water. PMID:22512191

Liu, Ke; Zhao, Wen-ji; Guo, Xiao-yu; Wang, Yi-hong; Sun, Yong-hua; Miao, Qian

2012-02-01

19

Coevolution of hydraulic, soil and vegetation processes in estuarine wetlands  

NASA Astrophysics Data System (ADS)

Estuarine wetlands of south eastern Australia, typically display a vegetation zonation with a sequence mudflats - mangrove forest - saltmarsh plains from the seaward margin and up the topographic gradient. Estuarine wetlands are among the most productive ecosystems in the world, providing unique habitats for fish and many terrestrial species. They also have a carbon sequestration capacity that surpasess terrestrial forest. Estuarine wetlands respond to sea-level rise by vertical accretion and horizontal landward migration, in order to maintain their position in the tidal frame. In situations in which buffer areas for landward migration are not available, saltmarsh can be lost due to mangrove encroachment. As a result of mangrove invasion associated in part with raising estuary water levels and urbanisation, coastal saltmarsh in parts of south-eastern Australia has been declared an endangered ecological community. Predicting estuarine wetlands response to sea-level rise requires modelling the coevolving dynamics of water flow, soil and vegetation. This paper presents preliminary results of our recently developed numerical model for wetland dynamics in wetlands of the Hunter estuary of NSW. The model simulates continuous tidal inflow into the wetland, and accounts for the effect of varying vegetation types on flow resistance. Coevolution effects appear as vegetation types are updated based on their preference to prevailing hydrodynamic conditions. The model also considers that accretion values vary with vegetation type. Simulations are driven using local information collected over several years, which includes estuary water levels, accretion rates, soil carbon content, flow resistance and vegetation preference to hydraulic conditions. Model results predict further saltmarsh loss under current conditions of moderate increase of estuary water levels.

Trivisonno, Franco; Rodriguez, Jose F.; Riccardi, Gerardo; Saco, Patricia; Stenta, Hernan

2014-05-01

20

Salvaged-Wetland Soil as a Technique to Improve Aquatic Vegetation at Created Wetlands in Wyoming, USA  

Microsoft Academic Search

Aquatic plants usually establish following wetland creation from a variety of mechanisms including animal transport, inflows from nearby wetlands, wind dispersal, and seed banks if they are available. However, at created wetlands that are isolated from natural wetlands, aquatic plant communities may not establish even after 10 or more years. One method of improving the establishment of aquatic plants is

Mark C. McKinstry; Stanley H. Anderson

2005-01-01

21

Integration of vegetation inventory data and ALOS image for vegetation classification in Yancheng coastal wetlands  

NASA Astrophysics Data System (ADS)

Systematic mapping and monitoring of wetland landscape are of fundamental importance for wetland development and management. To accurately classify wetland in Yancheng coastal wetland, ground investigation was conducted in 2006. Integrated with ground investigation, the wetland was classified into 8 categories such as Spartina alterniflora Loisel, Farm land, Phragmites Australis, Artemisia halodendron Turcz, Bare beach, Salt field, Fish & shrimp pond, and Sea water. A total of three decision trees were successfully produced. The first represented broad divisions of vegetation (in fact, at this stage, it just can be called vegetated cover like) and non-vegetation, and the second two represented more detailed vegetation classes and non-vegetation classes. To construct the decision trees, NDVI and principal component analysis were used as the evaluation factors. The thresholds were built combining with ground investigation and spectral property. Firstly, almost all kinds of vegetable were divided out of non-vegetation by NDVI. Secondly, the different species of vegetation were distinguished and some vegetated cover like was eliminated out of vegetation. Phragmites Australis belt, Artemisia halodendron Turcz belt, Spartina alterniflora Loisel belt and bare beach belt were distributed regularly from land to sea.

Li, Yunmei; Wu, Lan; Yang, Yu; Xia, Rui; Wang, Yanfei; Jin, Xing

2009-10-01

22

Wetland vegetation before and after experimental purple loosestrife removal  

Microsoft Academic Search

Purple loosestrife (Lythrum salicaria) is considered one of the worst invasive non-native species of North American wetlands, but its reputation rests on few published,\\u000a quantitative field studies. This study described the vegetation of two sites (one flooded, one drier) within a heavily invaded\\u000a wetland in southeastern New York, in order to investigate the common claim that purple loosestrife produces monospecific

Janet A. Morrison

2002-01-01

23

Multispectral and hyperspectral remote sensing for identification and mapping of wetland vegetation: a review  

Microsoft Academic Search

Wetland vegetation plays a key role in the ecological functions of wetland environments. Remote sensing techniques offer timely,\\u000a up-to-date, and relatively accurate information for sustainable and effective management of wetland vegetation. This article\\u000a provides an overview on the status of remote sensing applications in discriminating and mapping wetland vegetation, and estimating\\u000a some of the biochemical and biophysical parameters of wetland

Elhadi Adam; Onisimo Mutanga; Denis Rugege

2010-01-01

24

Performance Criteria, Compliance Success, and Vegetation Development in Compensatory Mitigation Wetlands  

NASA Astrophysics Data System (ADS)

The US Army Corps of Engineers often requires wetland creation or restoration as compensation for wetlands damaged during development. These wetlands are typically monitored postconstruction to determine the level of compliance with respect to site-specific performance standards. However, defining appropriate goals and measuring success of restorations has proven difficult. We reviewed monitoring information for 76 wetlands constructed between 1992 and 2002 to summarize the performance criteria used to measure progress, assess compliance with those criteria, and, finally, to evaluate the appropriateness of those criteria. Goals were overwhelmingly focused on plant communities. Attributes used to assess the quality of restored plant communities, including percent native species and the Floristic Quality Index, increased over time but were apparently unrelated to the number of species planted. Compliance frequencies varied depending on site goals; sites often failed to comply with criteria related to survival of planted vegetation or requirements that dominant plant species should not be exotic or weedy, whereas criteria related to the establishment of cover by vegetation or by wetland-dependent plants were often met. Judgment of a site’s success or failure was largely a function of the goals set for the site. Some performance criteria were too lenient to be of value in distinguishing failed from successful sites, whereas other criteria were unachievable without more intensive site management. More appropriate goals could be devised for restored wetlands by basing performance standards on past performance of similar restorations, identifying consistent temporal trends in attributes of restored sites, and using natural wetlands as references.

Matthews, Jeffrey W.; Endress, Anton G.

2008-01-01

25

Wetland Soils and Vegetation, Arctic Foothills, Alaska.  

National Technical Information Service (NTIS)

Analyses of relationships between hydric soils and wetland plant species were made at a 22 cu km site in the northern foothills of the Brooks Range, Alaska, as part of a cooperative effort between the FWS and SCS to develop methods for field identificatio...

M. D. Walker, D. A. Walker, K. R. Everett

1989-01-01

26

Early vegetational changes on a forested wetland constructed for mitigation  

USGS Publications Warehouse

Changes in vegetation were studied on 15 acres of a 35 acre forested wetland created as a mitigation site in Anne Arundel County, Maryland during 1994-96. Meter-square sampling on four different hydrologic elevations determined that grasses initially dominated the area, but decreased from 59 percent in 1994 to 51 percent in 1995 and 30 percent in 1996. Herbaceous non-grass plants (forbs) increased from 19 percent to 56 percent in the three-year period. Area with no plant cover decreased from 21 percent in 1994 to 11 percent in 1995, and 10 percent in 1996. Woody plants comprised 2 percent of the cover in 1994, increased to 4 percent in 1995, and remained at 4 percent in 1996. The increase of woody plants was mainly from natural regeneration (pioneer) plants. Monitoring of the transplanted trees and shrubs indicated 35 percent mortality and little growth of surviving plants. The pioneer woody plant forming most of the cover was black willow (Salix nigra). Differences in the vegetation were observed among the four elevations, although no differences were observed for the major vegetation classes between plots that were planted and those that were not planted with woody plants. Dominant grass species was redtop (Agrostis stolonifera), which comprised 51 percent of the cover in 1994 and 42 percent cover in 1995 and 23 percent in 1996. Other species that were common were bush clover (Lespedeza cuneata), Japanese clover (Lespedeza striata) and flat pea (Lathyrus sylvestris). All four of these dominant species were part of the original seed mixtures that were seeded on the site. A total of 134 species of plants was recorded on the site indicating a fairly diverse community for a newly established habitat.

Perry, M.C.; Osenton, P.C.; Sibrel, C.B.

1997-01-01

27

Vegetation establishment in convectively accelerated streams  

NASA Astrophysics Data System (ADS)

We study the conditions for vegetation establishment within river reaches with converging boundaries. Common to many such rivers worldwide is the existence of a limiting front (e.g., Figure 1a) beyond which all the riverbed vegetation is uprooted by flooding events. There are however exceptions, which leads to an interesting ecomorphodynamic problem (existence and position of the front). We use a theoretical 1-D framework based on morphodynamic equations modified in order to account for the presence of vegetation (Perona et al., submitted), and obtain the link between the position of the vegetated front and river eco-hydraulic variables under steady and unsteady conditions. We apply our framework to a number of flume experiments (unsteady flow) where Avena sativa L. (common oat) seedlings grow subject to periodic flow disturbances within a convergent flume channel (Figure 1b). We find that depending on the outcome of the competition between hydrological and biological processes there is either a limiting spatial front within the convergent section beyond which vegetation cannot survive, or vegetation colonizes the entire riverbed. The existence and the position of the front depend on the ability for vegetation to take root efficiently and withstand uprooting by the flow of the convectively accelerated stream (Crouzy et al., in press). The active role of vegetation and of unit streampower in this particular ecomorphodynamic process are then discussed in relation to the conceptual model of Gurnell and Petts (2006), and under the light of our theoretical and experimental results. REFERENCES - Crouzy, B., K. Edmaier, N. Pasquale and P. Perona (in press). Impact of floods on the statistical distribution of riverbed vegetation. Geomorphology doi:10.1016/j.geomorph.2012.09.013. - Gurnell A., Petts G. (2006). Trees as riparian engineers: The Tagliamento River, Italy. Earth Surface Processes and Landforms, 31: 1558--1574. - Perona, P., B. Crouzy, S. Mc Lelland, P. Molnar and C. Camporeale. Ecomorphodynamics of rivers with converging boundaries. Earth Surface Processes and Landforms, submitted.

Crouzy, B.; McLelland, S. J.; Molnar, P.; Camporeale, C.; Perona, P.

2013-12-01

28

Plant community, primary productivity, and environmental conditions following wetland re-establishment in the Sacramento-San Joaquin Delta, California  

USGS Publications Warehouse

Wetland restoration can mitigate aerobic decomposition of subsided organic soils, as well as re-establish conditions favorable for carbon storage. Rates of carbon storage result from the balance of inputs and losses, both of which are affected by wetland hydrology. We followed the effect of water depth (25 and 55 cm) on the plant community, primary production, and changes in two re-established wetlands in the Sacramento San-Joaquin River Delta, California for 9 years after flooding to determine how relatively small differences in water depth affect carbon storage rates over time. To estimate annual carbon inputs, plant species cover, standing above- and below-ground plant biomass, and annual biomass turnover rates were measured, and allometric biomass models for Schoenoplectus (Scirpus) acutus and Typha spp., the emergent marsh dominants, were developed. As the wetlands developed, environmental factors, including water temperature, depth, and pH were measured. Emergent marsh vegetation colonized the shallow wetland more rapidly than the deeper wetland. This is important to potential carbon storage because emergent marsh vegetation is more productive, and less labile, than submerged and floating vegetation. Primary production of emergent marsh vegetation ranged from 1.3 to 3.2 kg of carbon per square meter annually; and, mid-season standing live biomass represented about half of the annual primary production. Changes in species composition occurred in both submerged and emergent plant communities as the wetlands matured. Water depth, temperature, and pH were lower in areas with emergent marsh vegetation compared to submerged vegetation, all of which, in turn, can affect carbon cycling and storage rates. ?? Springer Science+Business Media B.V. 2009.

Miller, R.L.; Fujii, R.

2010-01-01

29

Diurnal Cycles of Trace Gas Transfer through Wetland Vegetation  

NASA Astrophysics Data System (ADS)

Natural and constructed wetlands are major sources of biogeochemical trace gases, and have recently gained attention as tools for passive remediation of discharging groundwater contaminated with volatile organic compounds (VOCs). Wetland plants act as conduits for the volatilization of dissolved compounds from the interstitial pore waters of aquatic sediments to the atmosphere, so clarifying the mechanisms of this vegetation-mediated gas transport is essential to understanding the emissions of compounds including methane and VOCs. The conservative gas tracer sulfur hexafluoride (SF6) was used to examine mechanisms of gas transport through the wetland macrophytes Scirpus acutus and Typha latifolia in greenhouse mesocosm experiments. The results provide novel experimental evidence for the enhancement by light of plant-mediated gas fluxes through S. acutus, a species with no previously documented light-activated gas transport mechanism. A nonlinear saturation model was fit to the tracer flux data using least-squares regression. The mechanism for this light-enhanced flux was investigated in additional experiments in which atmospheric humidity was deliberately manipulated. These results will be discussed with respect to the role of transpiration in enhancing plant-mediated gas transport. The SF6 flux data also quantify inter-species and seasonal variability in gas transfer rates, and capture the dynamics of pressurized gas flows in T. latifolia. A numerical model of gas transport mechanisms in the root and rhizosphere system was calibrated with experimental data and used to further examine mechanisms of gas exchange between saturated wetland sediments, vegetation, and the atmosphere.

Reid, M. C.; Ho, D. T.; Jaffe, P. R.

2010-12-01

30

Vegetation analysis of Burullus Wetland: a RAMSAR site in Egypt  

Microsoft Academic Search

We analyzed the vegetation of Lake Burullus at the deltaic Mediterranean coast of Egypt, the sand bar between its northern\\u000a shore and Mediterranean Sea, the water courses that drain into the lake and the wetland around it. Our ultimate aim was to\\u000a identify threatened species and communities and the environmental factors that affect their distribution in order to formulate\\u000a a

Kamal H. Shaltout; Yassin M. Al-Sodany

2008-01-01

31

The Importance of Local and Regional Factors on the Vegetation of Created Wetlands in Central Europe  

Microsoft Academic Search

We assessed the relative importance of regional and local processes to wetland plant diversity in created depressional wetlands\\u000a in Central Europe (Košské mokrade wetlands, central Slovakia). Twelve wetlands were sampled for vegetation, water chemistry,\\u000a morphological, and hydrological data in 2008. A total of 39 plant species were found in the wetlands, dominated by Typha latifolia L. The results support the

Marek Svitok; Richard Hrivnák; Helena O?ahe?ová; Daniela Dúbravková; Peter Pa?ove-Balang; Vladimír Slobodník

32

Carbon gas fluxes in re-established wetlands on organic soils differ relative to plant community and hydrology  

USGS Publications Warehouse

We measured CO2 and CH4 fluxes for 6 years following permanent flooding of an agriculturally managed organic soil at two water depths (~25 and ~55 cm standing water) in the Sacramento–San Joaquin Delta, California, as part of research studying C dynamics in re-established wetlands. Flooding rapidly reduced gaseous C losses, and radiocarbon data showed that this, in part, was due to reduced oxidation of "old" C preserved in the organic soils. Both CO2 and CH4 emissions from the water surface increased during the first few growing seasons, concomitant with emergent marsh establishment, and thereafter appeared to stabilize according to plant communities. Areas of emergent marsh vegetation in the shallower wetland had greater net CO2 influx (-485 mg Cm-1 h-1), and lower CH4 emissions (11.5 mg Cm-2 h-1), than in the deeper wetland (-381 and 14.1 mg Cm-2 h-1, respectively). Areas with submerged and floating vegetation in the deeper wetland had CH4 emissions similar to emergent vegetation (11.9 and 12.6 mg Cm-2 h-1, respectively), despite lower net CO2 influx (-102 gC m-2 h-1). Measurements of plant moderated net CO2 influx and CH4 efflux indicated greatest potential reduction of greenhouse gases in the more shallowly flooded wetland.

Miller, Robin L.

2011-01-01

33

Vegetation changes and partitioning of selenium in 4-year-old constructed wetlands treating agricultural drainage.  

PubMed

The knowledge of selenium (Se) partitioning in treatment wetlands and wetland vegetation management are essential for long-term effective operation of constructed wetlands treating Se-laden agricultural tile-drainage in central California. In this field study, samples from different compartments of treatment wetlands were collected and the vegetation change in each wetland cell was examined four years after the wetland's inception. The results showed that saltgrass (Distichlis spicata) and rabbitfoot grass (Polypogon monspeliensis) were less competitive than cattail (Typha latifolia) and saltmarsh bulrush (Scirpus robustus). Over 90% of the wetland cell originally vegetated with saltgrass or rabbitfoot grass was occupied by invasive plants--i.e., when invasive species were not controlled in the wetlands. More Se was likely found in sediments from vegetated regions, compared to the unvegetated areas of the wetland cell. Particularly, rhizosphere sediments accumulated about 4-fold more Se than non-rhizosphere sediments. Among the total Se retained in the wetland 90% of the total Se was partitioned in the top 10-cm layer of sediment. The Se accumulation in plant materials accounted for about 2% of the total Se mass retained in each wetland cell. This field study demonstrated that wetland plants play significant roles in the treatment of Se-laden agricultural drainage. PMID:20734620

Lin, Z Q; Terry, N; Gao, S; Mohamed, S; Ye, Z H

2010-03-01

34

Vegetative Ecological Characteristics of Restored Reed ( Phragmites australis) Wetlands in the Yellow River Delta, China  

NASA Astrophysics Data System (ADS)

In this study, we compared ecological characteristics of wetland vegetation in a series of restoration projects that were carried out in the wetlands of Yellow River Delta. The investigated characteristics include plant composition structure, species diversity and community similarity in three kinds of Phragmites australis wetlands, i.e. restored P. australis wetlands (R1, R2, R3 and R4: restored in 2002, 2005, 2007 and 2009, respectively), natural P. australis wetland (N) and degraded P. australis wetland (D) to assess the process of wetlands restoration. The coverage of the R1 was 99%, which was similar to natural wetland. Among all studied wetlands, the highest and lowest stem density was observed in R1 and R2, respectively, Plant height and stem diameter show the same trend as N > R2 > R1 > R3 > D > R4. Species diversity of restored P. australis wetlands became closed to natural wetland. Both species richness and Shannon-Wiener index had similar tendency: increased first and then decreased with restored time. The highest species richness and species diversity were observed in R2, while the lowest values of those parameters were found in natural P. australis wetland. Similarity indexes between restored wetlands and natural wetland increased with the restoration time, but they were still less than 50%. The results indicate that the vegetation of P. australis wetlands has experienced a great improvement after several years' restoration, and it is feasible to restored degraded P. australis wetlands by pouring fresh water into those wetlands in the Yellow River Delta. However, it is notable that costal degraded P. australis wetland in this region may take years to decades to reach the status of natural wetland.

Wang, Xuehong; Yu, Junbao; Zhou, Di; Dong, Hongfang; Li, Yunzhao; Lin, Qianxin; Guan, Bo; Wang, Yongli

2012-02-01

35

Tissue culture and wetland establishment of the freshwater monocots Carex, Juncus, Scirpus , and Typha  

Microsoft Academic Search

Summary  Cell cultures of freshwater wetland monocots were regenerated, plants were grown in the greenhouse, and then established and\\u000a evaluated in wetlands. Typha (cattail), Juncus (rushes), Scirpus (bulrushes), and Carex (sedges) were studied because they are common, dominant, high biomass wetland-adapted plants, tolerant of chemically diverse\\u000a ecosystems. The goal was to define micropropagation and wetland establishment protocols. Tissue culture systems defined

Suzanne M. D. Rogers

2003-01-01

36

The role of hydrodynamic transport in greenhouse gas fluxes at a wetland with emergent vegetation  

NASA Astrophysics Data System (ADS)

In wetlands with emergent vegetation, the hydrodynamic transport of dissolved gases is often neglected because emergent plants transport gases directly and limit wind-driven air-water gas exchange by sheltering the water surface. Nevertheless, wetland hydrodynamics, and thermally-driven stirring in particular, have the potential to impact gas fluxes in these environments. We are evaluating the importance of hydrodynamic dissolved gas transport at a re-established marsh on Twitchell Island in the Sacramento-San Joaquin Delta (California, USA). At this marsh, the U.S. Geological Survey has previously observed rapid accumulation of organic material (carbon sequestration) as well as very high methane emissions. To assess the role of hydrodynamics in the marsh's greenhouse gas fluxes, we measured dissolved carbon dioxide and methane in the water column on a bi-weekly basis beginning in July 2012. We employed a model for air-water gas fluxes in wetlands with emergent vegetation that predicts gas transfer velocities from meteorological conditions. Modeled air-water gas fluxes were compared with net gas fluxes measured at the marsh via the eddy covariance technique. This comparison revealed that hydrodynamic transport due to thermal convection was responsible for approximately one third of net carbon dioxide and methane fluxes. The cooling at the water surface driving thermal convection occurred each night and was most pronounced during the warmest months of the year. These finding have implications for the prediction and management of greenhouse gas fluxes at re-established marshes in the Sacramento-San Joaquin Delta and other similar wetlands.

Poindexter, C.; Gilson, E.; Knox, S. H.; Matthes, J. H.; Verfaillie, J. G.; Baldocchi, D. D.; Variano, E. A.

2013-12-01

37

Net primary productivity and spatial distribution of vegetation in an alpine wetland, Qinghai-Tibetan Plateau  

Microsoft Academic Search

To initially describe vegetation structure and spatial variation in plant biomass in a typical alpine wetland of the Qinghai-Tibetan\\u000a Plateau, net primary productivity and vegetation in relationship to environmental factors were investigated. In 2002, the\\u000a wetland remained flooded to an average water depth of 25 cm during the growing season, from July to mid-September. We mapped\\u000a the floodline and vegetation

Mitsuru Hirota; Kiyokazu Kawada; Qiwu Hu; Tomomichi Kato; Yanhong Tang; Wenhong Mo; Guangmin Cao; Shigeru Mariko

2007-01-01

38

Development of Vegetation Models to Predict the Potential Effect of Groundwater Withdrawals on Forested Wetlands  

Microsoft Academic Search

We developed vegetation models that, when linked to groundwater-hydrology models and landscape-level applications, can be\\u000a used to predict the potential effect of groundwater-level declines on the distribution of wetland-forest communities, individual\\u000a wetland species, and wetland-indicator groups. An upland-to-wetland vegetation gradient, comprising 201 forest plots located\\u000a in five different study basins and classified as either upland pine-oak, pitch pine lowland, pine-hardwood

Kim J. Laidig; Robert A. Zampella; Allison M. Brown; Nicholas A. Procopio

2010-01-01

39

Inundation, Wetland Vegetation and Biogeochemical Processes in the Amazon Basin  

NASA Astrophysics Data System (ADS)

Remote sensing of the Amazon basin with passive and active microwave techniques were applied to determine the temporally varying extent of inundation and associated vegetation, and used in conjunction with field measurements to calculate regional rates of carbon dioxide emission from wetlands to the atmosphere. Monthly inundation areas were derived from analysis of the 37-GHz polarization difference observed by the Scanning Multichannel Microwave Radiometer (1979 to 1987) for the mainstem Amazon floodplain in Brazil, the Llanos de Moxos (Beni and Mamore rivers) in Bolivia, the Bananal Island (Araguaia River) and Roraima savannas. Maximum areas subject to inundation, including permanent open waters in rivers and lakes, were as follows (in km2): mainstem Amazon 97,400; Moxos 92,000; Bananal 58,500, and Roraima 16,500. Data from the Japanese Earth Resources Satellite-1, L-band synthetic aperture radar were used to determine inundation and wetland vegetation for a quadrat in the central Amazon basin (0o N to 8o S, 72o W to 54o W) at high water (May-June 1996) and low water (October 1995). Flooded area of rivers and floodplains (> 100 m in width) ranged from 79,000 km2 to 290,000 km2. When combined with estimates of inundation associated with streams not detected by the radar, a maximum area of 350,000 km2 (or 20% of the quadrat) was flooded. Combining the areal extent of flooding and measurements of free dissolved CO2 with an evasion model leads to outgassing of CO2 from inundated surfaces to the atmosphere in the central Amazon of 1.1 plus or minus 0.2 MgC ha-1 y-1. Extrapolated over the whole basin, the flux is 10 times the fluvial export of organic carbon to the ocean.

Melack, J. M.; Hess, L. L.; Hamilton, S. K.; Richey, J. E.; Novo, E. M.

2001-12-01

40

Characterization of microtopography and its influence on vegetation patterns in created wetlands  

USGS Publications Warehouse

Created wetlands are increasingly used to mitigate wetland loss. Thus, identifying wetland creation methods that enhance ecosystem development might increase the likelihood of mitigation success. Noting that the microtopographic variation found in natural wetland settings may not commonly be found in created wetlands, this study explores relationships between induced microtopography, hydrology, and plant species richness/ diversity in non-tidal freshwater wetlands, comparing results from two created wetland complexes with those from a mature reference wetland complex in northern Virginia. Elevation, steel rod oxidation depth, and species cover were measured along replicate multiscale (0.5 m-, 1 m-, 2 m-, and 4 m-diameter) tangentially conjoined circular transects in each wetland. Microtopography was surveyed using a total station and results used to derive three roughness indices: tortuosity, limiting slope, and limiting elevation difference. Steel rod oxidation depth was used to estimate water table depth, with data collected four times during the growing season for each study site. Plant species cover was estimated visually in 0.2 m2 plots surveyed at peak growth and used to assess species richness, diversity, and wetland prevalence index. Differences in each attribute were examined among disked and non-disked created wetlands and compared to a natural wetland as a reference. Disked and non-disked created wetlands differed in microtopography, both in terms of limiting elevation difference and tortuosity. However, both were within the range of microtopography encompassed by natural wetlands. Disked wetlands supported higher plant diversity and species richness than either natural or non-disked wetlands, as well as greater within-site species assemblage variability than non-disked wetlands. Irrespective of creation method, plant diversity in created wetlands was correlated with tortuosity and limiting elevation difference, similar to correlations observed for natural wetlands. Vegetation was more hydrophytic at disked sites than at non-disked sites, and of equivalent wetland indicator status to natural sites, even though all sites appeared comparable in terms of hydrology. Results suggest that disking may enhance vegetation community development, thus better supporting the goals of wetland mitigation. ?? 2007, The Society of Wetland Scientists.

Moser, K.; Ahn, C.; Noe, G.

2007-01-01

41

Modeling surface water flow through emergent vegetation in a small floodplain wetland  

NASA Astrophysics Data System (ADS)

Modeling of relatively shallow surface water flow through emergent vegetation is important in wetlands and on floodplains. In wetlands with surface flow, outflow is determined at least in part by hydraulic resistance from vegetation. However, estimates of vegetative resistance are highly dependent on vegetative form and density and flow regime. Predictive relationships that determine hydraulic resistance parameters from vegetation and flow properties were developed from flume experiments through woolgrass (Scirprus cyperinus) and used to estimate the spatial distribution of hydraulic resistance of a small floodplain wetland in northern Virginia. MODFLOW has been used as a tool to model peatland and wetland systems by treating the top vegetated open water surface model layer as a highly conductive aquifer layer, allowing interaction between the surface and subsurface flows. Conductivity of the surface vegetated layer was estimated using the relationships between hydraulic resistance and vegetation properties developed from the woolgrass flume data. An eight-hour controlled flow event through the wetland was simulated using MODFLOW with the goal of validating the predictive vegetative resistance relationships for surface flow. Initial results indicate vegetative resistance is difficult to estimate; unlike saturated hydraulic conductivity of aquifer layers, conductivity of surface vegetation is dependent on flow regime for flows typical of surface flow wetlands. Modeling surface flow through vegetation requires some fore knowledge of the expected flow conditions if an accurate simulation is to be achieved. If surface water flows can be successfully modeled using MODFLOW, the model can be extended to model the water budget of wetlands beyond a single flow event.

Piercy, C.; Wynn, T.; Ludwig, A.

2009-12-01

42

An assessment of the aquatic and wetland vegetation of the Upper Mississippi River  

Microsoft Academic Search

Illinois, Iowa, Minnesota, Missouri, and Wisconsin have strong botanical traditions that have resulted in a macrophyte literature which documents the identity, taxonomy, floristics, and ecology of aquatic macrophytes and wetland vegetation of the Upper Mississippi River and its floodplain. These findings are reviewed with respect to floristics, vegetation dynamics (patterns, history, production and management), and environmental changes that impact vegetation.

James H. Peck; Miles M. Smart

1986-01-01

43

Dual-season mapping of wetland inundation and vegetation for the central Amazon basin  

Microsoft Academic Search

Wetland extent was mapped for the central Amazon region, using mosaicked L-band synthetic aperture radar (SAR) imagery acquired by the Japanese Earth Resources Satellite-1. For the wetland portion of the 18×8° study area, dual-season radar mosaics were used to map inundation extent and vegetation under both low-water and high-water conditions at 100-m resolution, producing the first high-resolution wetlands map for

Laura L. Hess; John M. Melack; Evlyn M. l. m. Novo; Claudio C. f. Barbosa; Mary Gastil

2003-01-01

44

Promoting species establishment in a phragmites-dominated great lakes coastal wetland  

USGS Publications Warehouse

This study examined efforts to promote species establishment and maintain diversity in a Phragmites-dominated wetland where primary control measures were underway. A treatment experiment was performed at Crane Creek, a drowned-river-mouth wetland in Ottawa National Wildlife Refuge along the shore of western Lake Erie. Following initial aerial spraying of Phragmites with glyphosate, this study tested combinations of cutting, raking, and additional hand spraying of Phragmites with glyphosate as methods to promote growth of other wetland species and increase plant diversity. Percent-cover vegetation data were collected in permanent plots before and after treatments, and follow-up sampling was performed the following year. Increased species richness, species emergence, and relative dominance of non-Phragmites taxa were used as measures of treatment success. We also examined treatment effects on Phragmites cover. Dimensionality of seedbank and soil properties was reduced using principal component analysis. With the exception of nitrogen, soil nutrients affected species establishment, non-Phragmites taxa dominance, and Phragmites cover. A more viable seedbank led to greater species emergence. Treatments had differential effects on diversity depending on elevation and resulting degree of hydrologic inundation. Whereas raking to remove dead Phragmites biomass was central to promoting species establishment in dry areas, spraying had a greater impact in continually inundated areas. For treatment success across elevations into the year following treatments, spraying in combination with cutting and raking had the greatest effect. The results of this study suggest that secondary treatments can produce a short-term benefit to the plant community in areas treated for Phragmites.

Carlson, M. L.; Kowalski, K. P.; Wilcox, D. A.

2009-01-01

45

Establishment, persistence, and management implications of experimental wetland plant communities  

Microsoft Academic Search

We inoculated 120 wetland microcosms representing 24 different environmental treatments with seeds from a carefully chosen\\u000a pool of 20 wetland plant species. The treatments were chosen to represent a variety of riverine and lacustrine wetlands, including\\u000a those with slow-growing, rare species. In the first season, an annual (Bidens cernua) was most abundant in all the microcosms. Both flooding and high

Evan Weiher; Irene C. Wisheu; Paul A. Keddy; Dwayne R. J. Moore

1996-01-01

46

Surface-water transport of suspended matter through wetland vegetation of the Florida everglades  

E-print Network

Surface-water transport of suspended matter through wetland vegetation of the Florida everglades; accepted 4 September 2003; published 7 October 2003. [1] The mobility of waterborne particulate matter plays an important role in the water quality, landscape evolution, and ecology of freshwater wetlands

Saiers, James

47

Trends of Change in Composition and Structure of Chicago Region Wetland Vegetation  

Microsoft Academic Search

Summary To understand long-term changes in Chicago region wetlands, in 2002 we investigated the status of 31 high quality grass- or sedge-dominated wetland plant communities that were originally sampled in 1976. Our objectives were to quantify vegetation changes over time by resampling transects and then correlating changes with site fire histories, as well as other factors linked with compositional and

Marlin Bowles; Michael Jones

2006-01-01

48

Influence of hummocks and emergent vegetation on hydraulic performance in a surface flow wastewater treatment wetland  

Microsoft Academic Search

A series of tracer experiments were conducted biannually at the start and end of the vegetation growing season in a surface flow wastewater treatment wetland located near Phoenix, AZ. Tracer experiments were conducted prior to and following reconfiguration and replanting of a 1.2 ha treatment wetland from its original design of alternating shallow and deep zones to incorporate hummocks (shallow

Steffanie H. Keefe; Robert L. Runkel; Roland D. Wass; Eric A. Stiles; Larry B. Barber

2010-01-01

49

DEVELOPING A WETLAND MONITORING AND ASSESSMENT PROGRAM; BIOLOGICAL ASSESSMENT CRITERIA FOR VEGETATION  

EPA Science Inventory

The Montana Natural Heritage Program will sample and evaluate riverine and depressional wetlands in the Middle Milk watershed in the Great Plains ecoregion. We will sample wetlands across a human disturbance gradient and collect data on vegetation structure and composition and e...

50

RESPONSES OF WETLAND VEGETATION TO WATER LEVEL VARIATIONS IN LAKE ONTARIO  

Microsoft Academic Search

Water level fluctuations, a naturally occurring phenomena in the Great Lakes, cause a continuing rejuvenation of lake-influenced wetlands. Two Lake Ontario wetlands (Campbell and Sage Creek Marshes) were mapped for 1 ft. contour intervals and habitat-vegetation type. Historical habitat\\/vegetation conditions were evaluated through interpretation of aerial photography. The photography was selected to represent water levels different from the current. Habitat

Wolf-Dieter N. Busch; Lynn M. Lewis

1984-01-01

51

Influences of channelization on discharge of suspended sediment and wetland vegetation in Kushiro Marsh, northern Japan  

NASA Astrophysics Data System (ADS)

The effects of wetlands on hydrology, water quality, and wildlife habitat are internationally recognized. Protecting the remaining wetlands is one of the most important environmental issues in many countries. However wetlands in Japan have been gradually shrinking due to agricultural development and urbanization, which generally lowers the groundwater level and introduces suspended sediment and sediment-associated nutrients into wetlands. We examined the influences of channelization on discharge of suspended sediment and wetland vegetation in Hokkaido, northern Japan. The impact of river channelization was confirmed not only by the sediment budgets but also by river aggradation or degradation after the channelization and by the resultant vegetational changes. The budgets of suspended sediment demonstrated that wash load was the predominant component accounting for 95% of the total suspended load delivered into the wetland. This suspended sediment was primarily transported into the wetland by flooding associated with heavy rainfall. Twenty-three percent of the wash load and 63% of the suspended bed material load were deposited in the channelized reach, which produced aggradation of about 2 m at the end of the reach. A shorting of the length of the channel, due to channelization of a meandering river, steepened the slope and enhanced the stream power to transport sediment. This steepening shifted the depositional zones of fine sediment 5 km downstream and aggraded the riverbed. Development of the watershed may increase not only the water discharge but also the amount of suspended sediments. The aggradation reduced the carrying capacity of the channel and caused sediment ladened water to flood over the wetlands. The fine sediment accumulated on the wetlands gradually altered the edaphic conditions and wetland vegetation. A low percentage (10 to 15%) of organic contents of wetlands' soil is more evidence indicating that the present condition is far different from normal. Original vegetation such as sedges and Alnus japonica were disappearing from the adjacent areas of the river channel and were being replaced by willow trees ( Salix spp.).

Nakamura, Futoshi; Sudo, Tadashi; Kameyama, Satoshi; Jitsu, Mieko

1997-03-01

52

Impact of Multiple Environmental Stresses on Wetland Vegetation Dynamics  

NASA Astrophysics Data System (ADS)

This research quantifies the impacts of climate change on the dynamics of wetland vegetation under the effect of multiple stresses, such as drought, water-logging, shade and nutrients. The effects of these stresses are investigated through a mechanistic model that captures the co-evolving nature between marsh emergent plant species and their resources (water, nitrogen, light, and oxygen). The model explicitly considers the feedback mechanisms between vegetation, light and nitrogen dynamics as well as the specific dynamics of plant leaves, rhizomes, and roots. Each plant species is characterized by three independent traits, namely leaf nitrogen (N) content, specific leaf area, and allometric carbon (C) allocation to rhizome storage, which govern the ability to gain and maintain resources as well as to survive in a particular multi-stressed environment. The modeling of plant growth incorporates C and N into the construction of leaves and roots, whose amount of new biomass is determined by the dynamic plant allocation scheme. Nitrogen is internally recycled between pools of plants, litter, humus, microbes, and mineral N. The N dynamics are modeled using a parallel scheme, with the major modifications being the calculation of the aerobic and anoxic periods and the incorporation of the anaerobic processes. A simple hydrologic model with stochastic rainfall is used to describe the water level dynamics and the soil moisture profile. Soil water balance is evaluated at the daily time scale and includes rainfall, evapotranspiration and lateral flow to/from an external water body, with evapotranspiration loss equal to the potential value, governed by the daily average condition of atmospheric water demand. The resulting feedback dynamics arising from the coupled system of plant-soil-microbe are studied in details and species’ fitnesses in the 3-D trait space are compared across various rainfall patterns with different mean and fluctuations. The model results are then compared with those from experiments and field studies reported in the literature, providing insights about the physiological features that enable plants to thrive in different wetland environments and climate regimes.

Muneepeerakul, C. P.; Tamea, S.; Muneepeerakul, R.; Miralles-Wilhelm, F. R.; Rinaldo, A.; Rodriguez-Iturbe, I.

2009-12-01

53

Denitrification Potential and Organic Matter as Affected by Vegetation Community, Wetland Age, and Plant Introduction in Created Wetlands  

Microsoft Academic Search

Denitrification potential (DP) and organic matter (OM) in soils were compared in three different vegetation communities—emergent mac- rophyte, open water, and forested edge—in two 10-yr-old created river- ine wetlands. Organic matter, cold water-extractable organic matter (CWEOM), anaerobic mineralizable carbon (AnMC), and DP varied significantly (P , 0.05) among vegetation communities. The surface (0 to 9 cm) soils in the emergent

Maria E. Hernandez; William J. Mitsch

2007-01-01

54

Spatial and Temporal Variability of Soils as it Relates to Vegetation Zonation in a Tropical Wetland  

NASA Astrophysics Data System (ADS)

Wetland ecosystems provide a range of important ecosystem services, including provisioning, regulating and cultural services. Globally wetlands have come under increasing anthropogenic pressure, and many need to be restored. An important component of this is understanding the relationship between soils and plant zonation in tropical wetlands. The edaphic characteristics of wetland soils typically occur in gradients and have been the focus of intensive research as it relates to vegetation zonation. Because much of this research has been focused in temperate regions relatively little is still known about the importance of edaphic factors mainly salinity to the zonation of vegetation in a tropical wetland. Here, we use a geophysical response surface directed sampling approach to determine important soil properties and controls on vegetation zonation in a tropical wetland. By using geophysical imaging to determine the spatial patterns of salinity, soil physio-chemical properties and to compare plant community patterns within geophysical signals in the Godineau swamp, we were able to determine the major soil factors which influence plant zonation within a tropical wetland. Analysis revealed that salinity is a major soil factor that differentiates plant communities. Grasses thrived at higher elevations which had lower clay and salt levels and sedges dominated under lower elevations with higher clay and salt levels. Keywords: Vegetation pattern, EC, EMI, geophysics

Atwell, M.; Robinson, D. A.; Wuddivira, M. N.; Gobin, J.

2011-12-01

55

Influence of hummocks and emergent vegetation on hydraulic performance in a surface flow wastewater treatment wetland  

NASA Astrophysics Data System (ADS)

A series of tracer experiments were conducted biannually at the start and end of the vegetation growing season in a surface flow wastewater treatment wetland located near Phoenix, AZ. Tracer experiments were conducted prior to and following reconfiguration and replanting of a 1.2 ha treatment wetland from its original design of alternating shallow and deep zones to incorporate hummocks (shallow planting beds situated perpendicular to flow). Tracer test data were analyzed using analysis of moments and the one-dimensional transport with inflow and storage numerical model to evaluate the effects of the seasonal vegetation growth cycle and hummocks on solute transport. Following reconfiguration, vegetation coverage was relatively small, and minor changes in spatial distribution influenced wetland hydraulics. During start-up conditions, the wetland underwent an acclimation period characterized by small vegetation coverage and large transport cross-sectional areas. At the start of the growing season, new growth of emergent vegetation enhanced hydraulic performance. At the end of the growing season, senescing vegetation created short-circuiting. Wetland hydrodynamics were associated with high volumetric efficiencies and velocity heterogeneities. The hummock design resulted in breakthrough curves characterized by multiple secondary tracer peaks indicative of varied flow paths created by bottom topography.

Keefe, Steffanie H.; Daniels, Joan S. (Thullen); Runkel, Robert L.; Wass, Roland D.; Stiles, Eric A.; Barber, Larry B.

2010-11-01

56

Influence of hummocks and emergent vegetation on hydraulic performance in a surface flow wastewater treatment wetland  

USGS Publications Warehouse

A series of tracer experiments were conducted biannually at the start and end of the vegetation growing season in a surface flow wastewater treatment wetland located near Phoenix, AZ. Tracer experiments were conducted prior to and following reconfiguration and replanting of a 1.2 ha treatment wetland from its original design of alternating shallow and deep zones to incorporate hummocks (shallow planting beds situated perpendicular to flow). Tracer test data were analyzed using analysis of moments and the one-dimensional transport with inflow and storage numerical model to evaluate the effects of the seasonal vegetation growth cycle and hummocks on solute transport. Following reconfiguration, vegetation coverage was relatively small, and minor changes in spatial distribution influenced wetland hydraulics. During start-up conditions, the wetland underwent an acclimation period characterized by small vegetation coverage and large transport cross-sectional areas. At the start of the growing season, new growth of emergent vegetation enhanced hydraulic performance. At the end of the growing season, senescing vegetation created short-circuiting. Wetland hydrodynamics were associated with high volumetric efficiencies and velocity heterogeneities. The hummock design resulted in breakthrough curves characterized by multiple secondary tracer peaks indicative of varied flow paths created by bottom topography.

Keefe, Steffanie H.; Daniels, Joan S. (Thullen); Runkel, Robert L.; Wass, Roland D.; Stiles, Eric A.; Barber, Larry B.

2010-01-01

57

ASSESSING THE IMPACTS OF AN INCREASE IN WATER LEVEL ON WETLAND VEGETATION  

EPA Science Inventory

Three different approaches for assessing the impact of a permanent increase in water level on wetland vegetation were studied using a long-term, controlled, and replicated experiment. hese approaches were (1) digitized vegetation maps derived from aerial photographs; (2) vegetati...

58

Effects of vegetation management in constructed wetland treatment cells on water quality and mosquito production  

USGS Publications Warehouse

The impact of three vegetation management strategies on wetland treatment function and mosquito production was assessed in eight free water surface wetland test cells in southern California during 1998-1999. The effectiveness of the strategies to limit bulrush Schoenoplectus californicus culm density within the cells was also investigated. Removing accumulated emergent biomass and physically limiting the area in which vegetation could reestablish, significantly improved the ammonia - nitrogen removal efficiency of the wetland cells, which received an ammonia-dominated municipal wastewater effluent (average loading rate = 9.88 kg/ha per day NH4-N). We determined that interspersing open water with emergent vegetation is critical for maintaining the wetland's treatment capability, particularly for systems high in NH4-N. Burning aboveground plant parts and thinning rhizomes only temporarily curtailed vegetation proliferation in shallow zones, whereas creating hummocks surrounded by deeper water successfully restricted the emergent vegetation to the shallower hummock areas. Since the hummock configuration kept open water areas interspersed throughout the stands of emergent vegetation, the strategy was also effective in reducing mosquito production. Decreasing vegetation biomass reduced mosquito refuge areas while increasing mosquito predator habitat. Therefore, the combined goals of water quality improvement and mosquito management were achieved by managing the spatial pattern of emergent vegetation to mimic an early successional growth stage, i.e. actively growing plants interspersed with open water. ?? 2002 Elsevier Science B.V. All rights reserved.

Thullen, J. S.; Sartoris, J. J.; Walton, W. E.

2002-01-01

59

Variability of soil microbial respiration under different vegetation succession stages in Jiuduansha wetland  

Microsoft Academic Search

The soil microbial respiration (SMR) and physicochemical characteristics of Jiuduansha wetland at the Yangtze Estuary were analyzed in order to clarify the variability of SMR under different vegetation succession stages and its influencing factors. The results indicated that SMR of different vegetation succession stages are significantly various (P < 0.05). The SMR of the Spartina alterniflora (S. alterniflora) zone (0.43

Yushu Tang; Lei Wang; Jianwei Jia; Yanli Li; Wenquan Zhang; Hongli Wang; Xiaohua Fu; Yiquan Le

2011-01-01

60

Vegetation development on extensive vegetated green roofs: Influence of substrate composition, establishment method and species mix  

Microsoft Academic Search

Technology for establishment of vegetated roofs (green roofs) has developed rapidly over recent years but knowledge about how these systems will develop over time is still limited. This study investigates vegetation development on unfertilised thin extensive vegetated roofs during a 3-year period. The vegetation systems investigated were designed to be low maintenance and had a saturated weight of 50kg\\/m2, a

Tobias Emilsson

2008-01-01

61

Transfer of tracers and pesticides in lab scale wetland systems: the role of vegetation  

NASA Astrophysics Data System (ADS)

Surface wetlands can collect contaminated runoff from urban or agricultural catchments and have intrinsic physical, chemical and biological retention and removal processes useful for mitigating contaminants, including pesticides, and thus limiting the contamination of aquatic ecosystems. Yet little is known about the transfer of pesticides between wetlands collecting pesticides runoff and groundwater, and the subsequent threat of groundwater contamination. In particular, the influence of wetland vegetation and related processes during pesticide transfer is largely unknown. Here we evaluate the transfer of the widely used herbicide Isoproturon (IPU) and the fungicide Metalaxyl (MTX) with that of Uranine (UR) and Sulphorhodamine (SRB) in a vegetated and a non-vegetated lab-scale wetland. UR and SRB had successfully served as a reference for pesticides in surface wetlands. We filled two 65 cm long and 15 cm diameter borosilicate columns with sediment cores from a wetland, one without and one with vegetation (Phragmites australis, Cav.). When a constant flow-through rate of 0.33 ml min-1 was reached, tracers and pesticides were injected simultaneously and continuously. The hydrological mass balance and tracer concentrations were measured daily at the outlet of the lab-scale wetland. Samples for pesticides and hydrochemical analyses were collected biweekly. The lab-scale wetlands were covered to limit evaporation and light decay of injected compounds. The reactive transfer of compounds in the vegetated and non-vegetated lab-scale wetland was compared based on breakthrough curves (BTC's) and model parameters of the lumped parameter model CXTFIT. The hydrologic balance revealed that the intensity of transpiration and hence plant activity in the lab-scale wetlands progressively decreased and then apparently ceased after about eight days following continuous pesticide injection. In this first phase, no significant difference in the hydrologic balances could be observed between the vegetated and the non-vegetated column. In a second phase, vegetation transpiration progressively increased, as inferred from lower volumes of effluent water in the vegetated system. Overall, the behavior of pesticides and tracers, as inferred from the BTC's, were similar. This suggests that fluorescent tracers may be used as a reference for pesticides when studying the surface-groundwater interface. Both pesticides and tracers showed larger recovery rates (UR: 81.7 to 78.6%; SRB: 65.6 to 55.9%; IPU: 76.6 to 79.7%; MTX: 39.5 to 37.5%) and lower retention in the vegetated system. We attribute this finding to preferential flow paths along plant roots. Overall, our study suggests that wetland vegetation and rhizosheric processes may have a dual role in wetland pollutant transfer: while wetland vegetation may enhance retention and bio-degradation of contaminants in surface water, it may also generate preferential flow paths and hence facilitate pollutant transfer to groundwater. Acknowledgment: This study has been funded by the European Union (INTERREG) in the framework of the PhytoRet Project.

Durst, R.; Imfeld, G.; Lange, J.

2012-04-01

62

Vegetation Response to Re-flooding in the Mesopotamian Wetlands, Southern Iraq  

Microsoft Academic Search

Wetlands in the Mesopotamian Plain in southern Iraq were extensively drained in the 1990s. Re-flooding of drained areas commenced\\u000a in 2003, and included parts of the Central marsh between the Euphrates and Tigris Rivers. New vegetation in the re-flooded\\u000a areas of the Central marsh was studied in 2006. Most of the wetland plant species and communities widely distributed prior\\u000a to

M. A. Hamdan; T. Asada; F. M. Hassan; B. G. Warner; A. Douabul; M. R. A. Al-Hilli; A. A. Alwan

2010-01-01

63

Vegetation effects on anammox spatial distribution and nitrogen removal in constructed wetlands treated with domestic sewage.  

PubMed

In this study, two horizontal subsurface-flow constructed wetlands (CWs) (planted and unplanted) were constructed and compared to investigate the effects of vegetation on nitrogen removal and anammox (anaerobic ammonium oxidation) spatial distribution and enrichment. Calamus (Acorus calamus L.), which has a large root system, was selected as the vegetation. Removal of total nitrogen from the planted wetland was much higher than that from the unplanted one. Radial oxygen loss from calamus provided the planted wetland with better oxygen restoration ability, benefitting ammonium removal in the CW, especially when anammox was inhibited under winter temperatures. Enrichment of anammox bacteria in planted wetlands was much greater than that in unplanted ones. The greatest enrichment of anammox bacteria occurred in the middle layer, which had a better anaerobic environment and moderate root system. The reduced rate of metabolism in plants during winter led to a sharp decrease in anammox bacteria copy numbers in the planted wetland. Under cold temperature, the degree of enrichment with anammox bacteria in the planted wetland was similar to or slightly superior to that in the unplanted wetland. PMID:25353942

Wang, Ling; Li, Tian

2014-10-01

64

Development of vegetation in a constructed wetland receiving irrigation return flows  

Microsoft Academic Search

The Fairview Constructed Wetland, a complex of replicated wet meadow (primary filter) and shallow marsh (shallow wetland) cells, was built in southeast Idaho in 1999 and planted with seven native plant species. The development of aboveground biomass and root mass and the accumulation of litter for each cell and for each species are described here. Establishment patterns varied among species

Andrew M. Ray; Richard S. Inouye

2007-01-01

65

The Effect of Manning's Roughness Calibration on Flow and Sediment transport in Wetlands: Vegetation Drag Approach  

NASA Astrophysics Data System (ADS)

Wetland hydrology is one of the most complex and important factors that dictate landscape patterning in wetlands. Understanding factors that affect wetland hydrology are very important. Subtropical wetlands with low gradient, such as The Everglades in South Florida, are generally covered by various type of vegetation with area of highly vegetated and area with almost no plant density. Ridge and slough are one of the several major habitat types in the Everglades that are characterized by highly vegetated ridge with higher elevation and channelized slough with less dense vegetation. They are originally consisted of a peat - based systems of dense sawgrass ridges (Cladium jamaicense) interspersed with adjacent and relatively open sloughs. Because of vegetation dynamics, the hydrology is highly depends on vegetation drag force. Kadlec (1990) and Shi et al., 1995 stated that additional drag exerted by plants reduces the mean flow velocity and depth within the vegetated regions. Vegetation flexibility (flexible grasslike vs. rigid or less flexible bushes or trees) may affect flow resistance. In addition, total or partially submerged vegetation may also change the flow velocity. Most of vegetation in wetlands are partially submerged and therefore, flow resistance can be related to bed shear stress (Yen, 2002; Wu et al., 1999). The new modified Manning's coefficient expression estimates roughness value based on vegetation type, length, density, and vegetation being submerged/unsubmerged (Wu et al., 1999). This modification was applied to flow simulation in the study area at Loxahatchee Impoundment Landscape Assessment (LILA). Loxahatchee Impoundment Landscape Assessment (LILA) is living laboratory of The Everglades and is located at Boynton Beach, Florida and consists of 80 acres land divided into four macrocosms of 200 m × 400 m. Each macrocosm includes one ridge one slough and two tree islands. Two of the cells are non flowing cells and the others are constant flowing cells in LILA. The constant flowing cell, M2, was selected as the study area. Flow was simulated using FLO2D, a FEMA approved program that simulates flow depth and velocity by using modified manning's roughness coefficient based on vegetation drag approach. The result of this simulation will provide an improved understanding of the effect of vegetation dynamics on hydrology and how different vegetation type and density may change flow velocity and therefore sediment transport over time.

Mahmoudi, M.; Nalesso, M.; Garcia, R. F.; Miralles-Wilhelm, F.

2013-05-01

66

Establishment of wetland vegetation on East Texas mine spoil  

E-print Network

(Echinochloa crusgaJli var. frumenraceae), and smartweed (Polygonum puncratum) seeds, and chufa (Cyperus esculenrus) and arrowhead (Sagirraria latifolia) tubers were subjected to 4 water regimes (spring drawdown, spring flooding, fall drawdown, fall flooding..., Fairfield, Texas, 1989. SD = spring drawdown, SS = spring submerged, FD = fall drawdown, FS = fall submerged. 13 Mean total tuber biomass, individual tuber biomass, tuber number, and biomass index for S. latifolia under 4 water regime treatments at Big...

McKnight, Steven Keith

2012-06-07

67

A comparison of Aedes vigilax larval population densities and associated vegetation categories in a coastal wetland, Northern Territory, Australia.  

PubMed

Darwin's northern suburbs border an extensive coastal reed and upper mangrove wetland recognized as an important larval habitat for Aedes vigilax (Skuse), the northern salt marsh mosquito, an established vector for Ross River and Barmah Forest viruses and an appreciable pest species. We sought to identify the most important vegetation categories associated with Ae. vigilax breeding to maximize the efficiency of mosquito control efforts. Using a generalized linear model with negative binominal distribution and log link, this study compares larval densities, determined by focused dipping, between 13 discernable vegetation categories. The incidence rate ratios (RR) generated can be used to compare the magnitude of larval densities for each vegetation category, compared with the reference category. Aedes vigilax larval densities were almost ten times greater in artificial drainage areas (RR=9.82), followed by tide-affected reticulate (Sporobolus/Xerochloa) areas (RR=8.15), then Schoenoplectus/mangroves (RR=2.29), compared with the reference vegetation category "lower mangroves." Furthermore, larval densities were highest in May, due to tidal inundation, for drainage areas and tide-affected reticulates (RR=12.2, 11.7, respectively) compared with March, the reference month. Thus, to maximize the efficiency of aerial salt marsh mosquito control operations in this wetland, larval control is best accomplished by concentrating on drains, Schoenoplectus/mangroves, and tide-affected reticulate areas, commencing early after the wet season. These results should apply to other areas of salt marsh mosquito breeding across northern Australia. PMID:20836834

Jacups, S P; Kurucz, N; Whelan, P I; Carter, J M

2009-12-01

68

Establishment of Carex stricta Lam. seedlings in experimental wetlands with implications for restoration  

Microsoft Academic Search

The loss of Carex dominated meadows due to agricultural drainage in the previously glaciated midcontinent of North America has been extensive.\\u000a The lack of natural Carex recruitment in wetland restorations and the failures of revegetation attempts underscore the need for information on the\\u000a establishment requirements of wetland sedges. In this study, seedlings of Carex stricta Lam. were planted in three

Rachel A. Budelsky; Susan M. Galatowitsch

2004-01-01

69

Mapping swamp timothy (Cripsis schenoides) seed productivity using spectral values and vegetation indices in managed wetlands  

SciTech Connect

This work examines the potential to predict the seed productivity of a key wetland plant species using spectral reflectance values and spectral vegetation indices. Specifically, the seed productivity of swamp timothy (Cripsis schenoides) was investigated in two wetland ponds, managed for waterfowl habitat, in California's San Joaquin Valley. Spectral reflectance values were obtained and associated spectral vegetation indices (SVI) calculated from two sets of high resolution aerial images (May 11, 2006 and June 9, 2006) and were compared to the collected vegetation data. Vegetation data were collected and analyzed from 156 plots for total aboveground biomass, total aboveground swamp timothy biomass, and total swamp timothy seed biomass. The SVI investigated included the Simple Ratio (SR), Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), Transformed Soil Adjusted Vegetation Index (TSAVI), Modified Soil Adjusted Vegetation Index (MSAVI), and Global Environment Monitoring Index (GEMI). We evaluated the correlation of the various SVI with in situ vegetation measurements for linear, quadratic, exponential and power functions. In all cases, the June image provided better predictive capacity relative to May, a result that underscores the importance of timing imagery to coincide with more favorable vegetation maturity. The north pond with the June image using SR and the exponential function (R{sup 2}=0.603) proved to be the best predictor of swamp timothy seed productivity. The June image for the south pond was less predictive, with TSAVI and the exponential function providing the best correlation (R{sup 2}=0.448). This result was attributed to insufficient vegetal cover in the south pond (or a higher percentage of bare soil) due to poor drainage conditions which resulted in a delay in swamp timothy germination. The results of this work suggest that spectral reflectance can be used to estimate seed productivity in managed seasonal wetlands.

Rahilly, P.J.A.; Li, D.; Guo, Q.; Zhu, J.; Ortega, R.; Quinn, N.W.T.; Harmon, T.C.

2010-01-15

70

Effects of power-line construction on wetland vegetation in Massachusetts, USA  

NASA Astrophysics Data System (ADS)

Utility rights-of-way corridors through wetland areas generate long-term impacts from construction activities to these valuable ecosystems. Changes to and recovery of the vegetation communities of a cattail marsh, wooded swamp, and shrub/bog wetland were documented through measurements made each growing season for two years prior, five years following, and again on the tenth year after construction of a 345-kV transmission line. While both the cattail marsh and wooded swamp recovered within a few years, measures of plant community composition in the shrub/bog wetland were still lower, compared to controls, after ten years. Long-term investigations such as the one reported here help decrease uncertainty and provide valuable information for future decision making regarding construction of power utility lines through valuable and dwindling wetland resources.

Nickerson, Norton H.; Dobberteen, Ross A.; Jarman, Nancy M.

1989-07-01

71

Vegetation Change in Great Lakes Coastal Wetlands: Deviation from the Historical Cycle  

Microsoft Academic Search

Water-level change is integral to the structure and function of Great Lakes coastal wetlands, and many studies document predictable relationships between vegetation and water level. However, anthropogenic stressors, such as invasive species, land-use change, and water-level stabilization, interact to shift the historical cycle (of native vegetation migration up- and down-slope) toward dominance by invasive Typha species. Knowing from earlier studies

Christin B. Frieswyk; Joy B. Zedler

2007-01-01

72

Effects of landscape gradients on wetland vegetation communities: Information for large-scale restoration  

Microsoft Academic Search

Projects of the scope of the restoration of the Florida Everglades require substantial information regarding ecological mechanisms,\\u000a and these are often poorly understood. We provide critical base knowledge for Everglades restoration by characterizing the\\u000a existing vegetation communities of an Everglades remnant, describing how present and historic hydrology affect wetland vegetation\\u000a community composition, and documenting change from communities described in previous

Christa L. Zweig; Wiley M. Kitchens

2008-01-01

73

Long and short-term eVects of reindeer grazing on tundra wetland vegetation  

Microsoft Academic Search

We studied long-term (50 years) and short-term (4 years) eVects of summer grazing of reindeer on subarctic tundra wetland vegetation. The long-term eVects of summer grazing were studied by comparing vegetation on Finnish and Norwegian sides of the fence line separating reindeer grazing regimes. The Finnish side was intensively grazed and trampled throughout the year, whereas the Norwegian side was

Heidi Kitti; Bruce C. Forbes; Jari Oksanen

74

Long and short-term effects of reindeer grazing on tundra wetland vegetation  

Microsoft Academic Search

We studied long-term (50 years) and short-term (4 years) effects of summer grazing of reindeer on subarctic tundra wetland\\u000a vegetation. The long-term effects of summer grazing were studied by comparing vegetation on Finnish and Norwegian sides of\\u000a the fence line separating reindeer grazing regimes. The Finnish side was intensively grazed and trampled throughout the year,\\u000a whereas the Norwegian side was grazed in

Heidi Kitti; Bruce C. Forbes; Jari Oksanen

2009-01-01

75

Vegetation study to assess the nutrient uptake potential of emergent macrophytes in semi-arid wetlands  

NASA Astrophysics Data System (ADS)

Arc GIS software and ground verification was used to map vegetation of a downstream riparian wetland in the Las Vegas Wash. Monogeneric stands of Phragmites australis dominated the spatial distribution of emergent macrophytes. This paper aims to evaluate the aboveground biomass production and nutrients (total nitrogen and total phosphorus) content to determine the maximum nutrient removal efficiency by harvesting Typha domingensis and P. australis during their highest growth rate, in a semi arid wetlands. The average aboveground biomass of T. domingensis (5.61to11.07 kg m-2) was significantly higher than P. australis (2.49-6.35 kg m-2) in the month of July 2010. Despite the high nutrient concentration measured in P. australis aboveground tissue, the net standing stock accumulation potential was still higher in T. domingensis. The net aboveground standing stock of nutrients in the Las Vegas Wash wetlands was measured (approximately 26418.7 kg N and 1264.1 kg P) for P. australis and (approximately 5183.8 kg N and 272.83 kg P) for T. domingensis. Harvesting aboveground biomass from both species would remove total nitrogen significantly from the system but not total phosphorus. Furthermore, harvesting P. australis during the peak growth period might positively impact the semi arid wetlands because it will provide more ground for T. domingensis extension. The comparative analysis of the emergent vegetation potential for biomass accumulation, nutrient concentration and standing stock was not significantly different among humid and semi arid wetlands. The humid and semi arid wetlands are characterized by a better understanding of the long term function and processes associated with the nutrient uptake potential of wetlands vegetation.

Adhikari, A. R.; Acharya, K.; Yu, Z.

2011-12-01

76

Towards a Characterization of Wetland Invasive Vegetation Using a Combination of Field and Remote Sensing Techniques  

NASA Astrophysics Data System (ADS)

Creation of compensatory wetlands has been required in the U.S. since the late 1980s in an attempt to offset the massive decline in freshwater wetlands. To meet permitting requirements, vegetation composition in mitigation wetlands must be monitored for a minimum of five years following creation. Unfortunately, mitigated wetlands often lack the functionality of natural wetlands and may form hotspots for invasive plant species. However, wetland assessment is a time-consuming process that may also disturb fragile nascent plant communities. Thus there is a need for approaches that minimize disturbance, but still enable the collection of data over large portions of the landscape. Remote sensing, using hyperspectral imagery augmented by field data collection is a potential tool for rapid ecosystem assessment. In July 2010, vegetation community composition, spectral signatures of individual plant species, and plant canopies, and an aerial hyperspectral imagery dataset were obtained from two natural and two mitigation wetlands on the Rochester Institute of Technology (RIT) campus, Rochester, NY. We were able to locate specific wavelengths for four invasive plant species spectra that can be used to classify and map these species on the RIT campus with an overall accuracy of 94.34%. Reed canarygrass had a higher reflectance than the other three species and differences along the red-edge and near-infrared regions also enabled differentiation between broadleaf cattail and narrowleaf cattail. Values within the blue, red, red-edge, and near-infrared regions are needed to create a multi-spectral sensor with a larger emphasis on the red-edge and near-infrared regions. Such a sensor would be more readily available for land managers for classification and analysis of large plots of land, limiting the amount of time, personnel and funding needed to process the imagery and allowing managers to more rapidly identify patches of invasive plant species with minimal intrusion on sensitive wetland environments.

Dutcher, Nicole M.

77

Vegetation succession and carbon sequestration in a coastal wetland in northwest Florida: Evidence from carbon isotopes  

E-print Network

Vegetation succession and carbon sequestration in a coastal wetland in northwest Florida: Evidence from carbon isotopes Yonghoon Choi and Yang Wang Department of Geological Sciences, Florida State. Measurements of stable carbon isotopic ratios as well as carbon (C), nitrogen (N), and phosphorus (P) contents

Wang, Yang

78

Vegetation change in created emergent wetlands (1988–1996) in Connecticut (USA)  

Microsoft Academic Search

Changes in hydrology, water quality and vegetation were evaluated in four palustrine emergent wetland pairs, each including created and reference sites. Located along interstate highways, they were initially sampled in 1988 (Confer and Niering, 1992) and again in 1996. Overall, created sites showed significant decreases in open water and water depth between 1989 and 1996 compared to more stable conditions

H. H. Moore; W. A. Niering; L. J. Marsicano; M. Dowdell

1999-01-01

79

Effect of climate fluctuations on long-term vegetation dynamics in Carolina bay wetlands  

USGS Publications Warehouse

Carolina bays and similar depression wetlands of the U.S. Southeastern Coastal Plain have hydrologic regimes that are driven primarily by rainfall. Therefore, climate fluctuations such as drought cycles have the potential to shape long-term vegetation dynamics. Models suggest two potential long-term responses to hydrologic fluctuations, either cyclic change maintaining open emergent vegetation, or directional succession toward forest vegetation. In seven Carolina bay wetlands on the Savannah River Site, South Carolina, we assessed hydrologic variation and vegetation response over a 15-year period spanning two drought and reinundation cycles. Changes in pond stage (water depth) were monitored bi-weekly to monthly each year from 1989?2003. Vegetation composition was sampled in three years (1989, 1993, and 2003) and analyzed in relation to changes in hydrologic conditions. Multi-year droughts occurred prior to the 1989 and 2003 sampling years, whereas 1993 coincided with a wet period. Wetland plant species generally maintained dominance after both wet and dry conditions, but the abundances of different plant growth forms and species indicator categories shifted over the 15-year period. Decreased hydroperiods and water depths during droughts led to increased cover of grass, upland, and woody species, particularly at the shallower wetland margins. Conversely, reinundation and longer hydroperiods resulted in expansion of aquatic and emergent species and reduced the cover of flood-intolerant woody and upland species. These semi-permanent Upper Coastal Plain bays generally exhibited cyclic vegetation dynamics in response to climate fluctuation, with wet periods favoring dominance by herbaceous species. Large basin morphology and deep ponding, paired with surrounding upland forest dominated by flood-intolerant pines, were features contributing to persistence of herbaceous vegetation. Drought cycles may promote directional succession to forest in bays that are smaller, shallower, or colonized by flood-tolerant hardwoods.

Stroh, C. L.; De Steven, D.; Guntenspergen, G.R.

2008-01-01

80

Wetland vegetation responses to liming an Adirondack watershed  

Microsoft Academic Search

Watershed liming as a long-term mitigation strategy to neutralize lake acidity, from increasing acid deposition, was initiated in North America at Woods Lake in the west central Adirondack region of New York. In October 1989, a dose of 10 MT lime (83.5% CaCO[sub 3]) ha[sup [minus]1] was aerially applied to 48% of the watershed. The wetlands adjacent to Woods Lake

Mackun

1993-01-01

81

Soil-vegetation correlations in selected wetlands and uplands of North-Central Florida  

USGS Publications Warehouse

Vegetation on four hydric and two nonhydric soils series in north-central Florida was sampled as part of a national study examining the correspondence between wetland vegetation and soils. The wetland character of the vegetation was estimated by weighted average calculations using published wetland indicator values for individual plant species. The weighted averages produced an ordering of plant communities in general agreement with the hydric character of the soils. However, the two nonhydric soils has weighted average scores slightly below 3, normally considered the lowest end of the range of nonhydric vegetation. There was no clear or consistent effect of fire management on the weighted average scores. Vegetation strata (herbaceous, low shrub, tall shrub, and trees) were generally similar in weighted average values, with the wettest of the hydric soils tending to be low in all strata and the nonhydric soils tending to be high in all strata. However, strata differed considerably in the specific values for a single soil and in the specific rank ordering of soils in different strata.

Best, G. Ronnie; Wolfe, Charlotte; Segal, Debra S.

1990-01-01

82

Effects of vegetation manipulation on breeding waterfowl in prairie wetlands--a literature review  

USGS Publications Warehouse

Literature on the effects of fire and grazing on the wetlands used by breeding prairie waterfowl is reviewed. Both dabbling and diving ducks and their broods prefer wetlands with openings in the marsh canopy. Decreased use is commonly associated with decreased habitat heterogeneity caused by tall, robust hydrophytes such as Typha spp. and other species adapted to form monotypes in the absence of disturbance. Nearly all previous studies indicate that reductions in height and density of tall, emergent hydrophytes by fire and grazing (unless very intensive) generally benefit breeding waterfowl. Such benefits are an increase in pair density, probably related to increased interspersion of cover and open water which decreases visibility among conspecific pairs, and improvements in their invertebrate food resources that result from increased habitat heterogeneity. Research needs are great because of the drastic changes that have accrued to prairie wetlands through fire suppression, cultivation, and other factors. The physical and biological environments preferred by species of breeding waterfowl during their seasonal and daily activities should be ascertained from future studies in wetland complexes that exist in the highest state of natural preservation. Long-term burning and grazing experiments should follow on specific vegetatively-degraded wetlands judged to be potentially important breeding areas. Seasonality, frequency, and intensity of treatments should be varied and combined and, in addition to measuring the response of the biotic community, the changes in the physical and chemical environment of the wetlands should be monitored to increase our knowledge of causative factors and possible predictive values.

Kantrud, H.A.

1986-01-01

83

Interactions between vegetation and hydrology: 1) Forest structure and throughfall 2) Spruce expansion following wetland drying  

NASA Astrophysics Data System (ADS)

Chapter 1: We developed a non-linear regression model from first principals to predict the percent of precipitation interception from forest canopies using lidar as a measure of forest structure. To find the best parameters for the model, we measured thoroughfall of rain (n = 21), fresh snow (n = 21), and old snow (n = 26) on plots in the boreal forest of the upper Eklutna Valley, Alaska. We calculated a set of twelve lidar metrics for each plot, and found the combined metric of mean height * cover to be the lidar metric most highly correlated to ln(throughfall) for rain (r = -0.81), fresh snow (r = -0.79), and old snow (r = -0.73). Using mean height * cover in the interception model, we predicted mean interception for rainfall (20% +/- 3%), fresh snow (29% +/- 4%), and old snow (20% +/- 3%) across the vegetated portion of the upper Eklutna Valley. Chapter 2: Climate changes and subsequent landscape-level responses have been documented throughout Alaska. We investigated the expansion of black (Picea mariana) and white spruce (Picea glauca) into open, herbaceous palustrine wetlands on Joint Base Elemendorf-Richardson (JBER) in south-central Alaska. We classified random points in wetlands across JBER using imagery from 1950, 1981, and 2012 to identify the extent and rate of spruce expansion. Additionally, we sampled 75 field plots in wetlands to age spruce trees and survey understory vegetation. We found tree cover in wetlands to have increased substantially from 1950-2012 (44% to 87%) with expansion over time fitting a logistic growth model well. Aged tree cores showed a recruitment pulse beginning the in 1930's and had a cumulative age distribution matching the logistic growth model of tree cover over time. The logistic growth model suggest spruce expansion began slowly in the early 1800's, coincident with the start of the current warming trend in Alaska. Using one representative wetland, we classified points on a 10 m spaced regular grid in 1950, 1981, and 2012 to show spruce expansion moving down the elevational gradient within the wetland -- a pattern observed throughout closed basin wetlands on JBER. Additionally, we found spruce expansion related to understory vegetation and wetland drainage shape (open basin, closed basin, or mixed). Finally, we propose a mechanism for the expansion of spruce into palustrine wetlands based on the timing and extent of vernal pooling.

Stehle, Richard Craig

84

Nitrogen detection in the vegetation of prototype constructed wetlands using chlorophyll fluorescence  

NASA Astrophysics Data System (ADS)

Constructed wetlands are a very efficient, clean and economical way to remove organic contaminants from waste water. In the whole water cleaning process, some other complex processes, such as physical sedimentation, filtration, chemical precipitation, and material absorption by vegetation, are involved. The Nitrogen absorption efficiency by heliconnia psitacorumm, was studied at laboratory scale in a small reactor simulating a subsurface flow constructed wetland. Chlorophyll increasing was measured by fluorescence, using blue LED, 460 [nm] as excitation light source. Besides, spectral differences were observed in the spectral signal and in its derivative, indicating changes in the plant physiological response.

Rosero, Edison; Plazas, Lucero; Solarte, Efraín; Fernández, Adrián; Peña, Enrique; Peña, Miguel

2009-08-01

85

Hydrologic, soil, and vegetation gradients in remnant and constructed riparian wetlands in west-central Missouri, 2001-04  

USGS Publications Warehouse

A study was conducted by the U.S. Geological Survey in cooperation with the Missouri Department of Conservation at the Four Rivers Conservation Area (west-central Missouri), between January 2001 and March 2004, to examine the relations between environmental factors (hydrology, soils, elevation, and landform type) and the spatial distribution of vegetation in remnant and constructed riparian wetlands. Vegetation characterization included species composition of ground, understory, and overstory layers in selected landforms of a remnant bottomland hardwood ecosystem, monitoring survival and growth of reforestation plots in leveed and partially leveed constructed wetlands, and determining gradients in colonization of herbaceous vegetation in a constructed wetland. Similar environmental factors accounted for variation in the distribution of ground, understory, and overstory vegetation in the remnant bottomland forest plots. The primary measured determining factors in the distribution of vegetation in the ground layer were elevation, soil texture (clay and silt content), flooding inundation duration, and ponding duration, while the distribution of vegetation in the understory layer was described by elevation, soil texture (clay, silt, and sand content), total flooding and ponding inundation duration, and distance from the Marmaton or Little Osage River. The primary measured determining factors in the distribution of overstory vegetation in Unit 1 were elevation, soil texture (clay, silt, and sand content), total flooding and ponding inundation duration, ponding duration, and to some extent, flooding inundation duration. Overall, the composition and structure of the remnant bottomland forest is indicative of a healthy, relatively undisturbed flood plain forest. Dominant species have a distribution of individuals that shows regeneration of these species with significant recruitment in the smaller size classes. The bottomland forest is an area whose overall hydrology has not been significantly altered; however, portions of the area have suffered from hydrologic alteration by a drainage ditch that is resulting in the displacement of swamp and marsh species by colonizing shrub and tree species. This area likely will continue to develop into an immature flood plain forest under the current (2004) hydrologic regime. Reforestation plots in constructed wetlands consisted of sampling survival and growth of multiple tree species (Quercus palustris, pin oak; Carya illinoiensis, pecan) established under several production methods and planted at multiple elevations. Comparison of survival between tree species and production types showed no significant differences for all comparisons. Survival was high for both species and all production types, with the highest mortality seen in the mounded root production method (RPM?) Quercus palustris (pin oak, 6.9 percent), while direct seeded Quercus palustris at middle elevation and bare root Quercus palustris seedlings at the low elevation plots had 100 percent survival. Measures of growth (diameter and height) were assessed among species, production types, and elevation by analyzing relative growth. The greatest rate of tree diameter (72.3 percent) and height (65.3 percent) growth was observed for direct seeded Quercus palustris trees planted at a middle elevation site. Natural colonized vegetation data were collected at multiple elevations within an abandoned cropland area of a constructed wetland. The primary measured determining factors in the distribution of herbaceous vegetation in this area were elevation, ponding duration, and soil texture. Richness, evenness, and diversity were all significantly greater in the highest elevation plots as a result of more recent disturbance in this area. While flood frequency and duration define the delivery mechanism for inundation on the flood plain, it is the duration of ponding and amount of 'topographic capture' of these floodwaters in fluvial lan

Heimann, David C.; Mettler-Cherry, Paige A.

2004-01-01

86

Patterns of soil moisture and vegetation in constructed wetlands  

NASA Astrophysics Data System (ADS)

Early results from a new simple model for the study of eco-hydrological patterns in constructed wetland are presented. The model may simulate the case that a dominant plant tends to colonize neighbouring zones to the detriment of the other species, or that synergies between different species allow their survival under water or oxygen stress. Tasks such as of zonation and controlling invasive plants spreading by regulating water table depth and inundation timing are discussed on the base of the outcome of few numerical modelling exercises.

Ursino, N.

2009-04-01

87

Vegetation survey of Four Mile Creek wetlands. [Savannah River Plant  

SciTech Connect

A survey of forested wetlands along upper Four Mile Creek was conducted. The region from Road 3 to the creek headwaters was sampled to evaluate the composition of woody and herbaceons plant communities. All sites were found to fall into either the Nyssa sylvatica (Black Gum) -- Persea borbonia (Red Bay) or Nyssa sylvatica -- Acer rubrum (Red Maple) types. These community types are generally species-rich and diverse. Previous studies (Greenwood et al., 1990; Mackey, 1988) demonstrated contaminant stress in areas downslope from the F- and H-Area seepage basins. In the present study there were some indications of contaminant stress. In the wetland near H-Area, shrub basal area, ground cover stratum species richness, and diversity were low. In the area surrounding the F-Area tree kill zone, ground cover stratum cover and shrub basal area were low and ground cover stratum species richness was low. The moderately stressed site at F-Area also showed reduced overstory richness and diversity and reduced ground cover stratum richness. These results could, however, be due to the very high basal area of overstory trees in both stressed F-Area sites that would reduce light availability to understory plants. No threatened or endangered plant species were found in the areas sampled. 40 refs., 4 figs., 8 tabs.

Loehle, C.

1990-11-01

88

Surface elevation change and vegetation distribution dynamics in a subtropical coastal wetland: Implications for coastal wetland response to climate change  

NASA Astrophysics Data System (ADS)

The response of coastal wetlands to sea-level rise is receiving global attention and observed changes in the distribution of mangrove and salt marsh are increasingly associated with global climate change, particularly sea-level and temperature rise, and potentially elevated carbon dioxide. Processes operating over smaller-spatial scales, such as rainfall variability and nutrient enrichment are also proposed as possible short-term drivers of changes in the distribution of mangrove and salt marsh. We consider the response of mangrove and salt marsh in a subtropical estuary to changes in environmental variables over a 12 year period by comparing rates of surface elevation change and vegetation distribution dynamics to hydrological and climatic variables, specifically water level and rainfall. This period of analysis captured inter-annual variability in sea level and rainfall associated with different phases of the El Niño Southern Oscillation (ENSO). We found that the mangrove and salt marsh trend of increasing elevation was primarily controlled by position within the tidal prism, in this case defined by inundation depth and distance to the tidal channel. Rainfall was not a primary driver of elevation trends in mangrove and salt marsh, but rainfall and water level variability did influence variability in elevation over the study period, though cross-correlation of these factors confounds identification of a single process driving this variability. These results highlight the scale-dependence of coastal wetland vegetation distribution dynamics; the longer-term trend of surface elevation increase and mangrove encroachment of salt marsh correlated with global sea-level trends, while short-term variability in surface elevation was related to local variability in water level and rainfall. Rates of surface elevation increase were found to lag behind rates of water level change within the Tweed River, which may facilitate further expansion of mangrove into salt marsh. This study advocates integration of ecological and geomorphic techniques to understand the response of coastal wetlands to sea-level rise and climatic perturbations.

Rogers, Kerrylee; Saintilan, Neil; Woodroffe, Colin D.

2014-08-01

89

Wetland vegetation responses to liming an Adirondack watershed  

SciTech Connect

Watershed liming as a long-term mitigation strategy to neutralize lake acidity, from increasing acid deposition, was initiated in North America at Woods Lake in the west central Adirondack region of New York. In October 1989, a dose of 10 MT lime (83.5% CaCO[sub 3]) ha[sup [minus]1] was aerially applied to 48% of the watershed. The wetlands adjacent to Woods Lake showed two distinct community types: one dominated by Chamaedaphne calyculata, and one dominated by graminoids and other herbaceous species. Within two years, liming did not alter the structure of either community type, and changed the cover or frequency of only 6 of 64 individual taxa. Most of these changes occurred in the herbaceous community type. The only strong positive response to liming was a nearly threefold increase in cover of the rhizomatous sedge Cladium mariscoides. The cover of Carex interior and Sphagnum spp. benefited from lime addition, while cover of Drosera intermedia and Muhlenbergia uniflora, and frequency of Hypericum canadense responded negatively to lime. Liming influenced the competitive release of only three taxa, all forbs with small growth forms. The tissue chemistry of foliage and twigs of Myrica gale, Chamaedaphne calyculata, and Carex stricta in the Chamaedaphne calyculata community type clearly illustrated species-specific patterns of nutrient accumulation and allocation both before and after liming. Concentrations of 17 of 20 elements responded to liming, although the responses varied among species and plant parts. Carex foliage was least responsive to liming, and Chamaedaphne twigs were most responsive. Elemental changes in plant tissues will be reflected in litter and many influence long-term nutrient dynamics in the wetland community.

Mackun, I.R.

1993-01-01

90

Holocene Vegetation Dynamics of an Upper St. Lawrence River Wetland: Paleoecological Evidence for a Recent Increase in Cattail ( Typha )  

Microsoft Academic Search

Cattails (Typha latifolia L., Typha angustifolia L., and Typha x glauca Godr.) are the predominant emergent vegetation of upper St. Lawrence River coastal wetlands. We sought to describe Holocene\\u000a vegetation in a St. Lawrence River wetland to assess patterns of succession and examine the timing and potential causes of\\u000a a historic cattail invasion. Paleoecological analysis indicated presence of four distinct

Molly Beland Rippke; Matthew T. Distler; John M. Farrell

2010-01-01

91

The effect of vegetation on porewater composition in a natural wetland receiving acid mine drainage  

Microsoft Academic Search

The effect of plant growth on surface and porewater concentrations of Fe, Mn, Cu, and S within a natural wetland receiving\\u000a acidic spoil heap drainage was determined over a period of one year. Comparisons were made between unvegetated sites and those\\u000a colonized by either Phragmites australis or Eriophorum angustifolium. The presence of vegetation increased surface and porewater concentrations of Fe

Lesley C. Batty; Alan J. M. Baker; Bryan D. Wheeler

2006-01-01

92

Short-term responses of wetland vegetation after liming of an Adirondack watershed  

Microsoft Academic Search

Watershed liming has been suggested as a long-term mitigation strategy for lake acidity, particularly in areas subject to high levels of acidic deposition. However, virtually no information has been available on the impacts of liming on wetland vegetation. In 1989, 1100 Mg of limestone (83.5% CaCO[sub 3]) were aerially applied to 48% (100 ha) of the Woods Lake watershed in

I. R. Mackun; D. J. Leopold; D. J. Raynal

1994-01-01

93

Wetlands  

NSDL National Science Digital Library

Learners create a model of a wetland to observe how it absorbs and filters water from the environment. In part 1, learners make it "rain" on their wetland model and compare their predictions of where the water will go to where it actually goes. In part 2, learners consider and discuss the characteristics of wetland plants and animals and match pictures of different organisms to different types of wetlands. An addendum to the lesson provides extensive information, including photos, about wetland plants and animals, plus a section on "Types of Wetlands Found in New Jersey."

Jersey, New; Center, Liberty S.; Coalition, New J.

2006-01-01

94

Effects of intertidal wetland vegetation and suspended sediment on flow velocity profiles and turbulence characteristics  

NASA Astrophysics Data System (ADS)

Intertidal wetland vegetation has an important role in flow structure, suspended sediment movement and geomorphology evolution. This study performed a flume experiment using Scirpus mariqueter from the field to investigate the impact of wetland vegetation on flow structure. The experimental plans were designed based on the relative depth of flow depth to vegetation height, i.e., non-submerged, moderately submerged and completely submerged conditions. Based on the measured Reynolds stress distribution, the classical mixing length hypothesis was used to derive the new velocity profiles inside the canopy. The good agreement of the results demonstrated that this method can be used to predict the velocity distribution of the submerged flow with flexible vegetation. Through statistical analysis combined with the theory of the boundary layer and sediment movement dynamics, the turbulence intensity and fine sediment distributions within the canopy were also obtained. The results reveal the mechanism of the effect of vegetation on the water and sediment of tidal flat in theoretical terms and enhance the understanding of hydrodynamics within the canopy.

Wang, Xianye; Yuan, Dailiang; He, Qing; Wang, Xiekang

2014-06-01

95

Vegetation survey of Pen Branch and Four Mile Creek wetlands  

SciTech Connect

One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.

Not Available

1992-01-01

96

Vegetation survey of Pen Branch and Four Mile Creek wetlands  

SciTech Connect

One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.

Not Available

1992-10-01

97

Effects of Different Vegetation Zones on CH4 and N2O Emissions in Coastal Wetlands: A Model Case Study  

PubMed Central

The coastal wetland ecosystems are important in the global carbon and nitrogen cycle and global climate change. For higher fragility of coastal wetlands induced by human activities, the roles of coastal wetland ecosystems in CH4 and N2O emissions are becoming more important. This study used a DNDC model to simulate current and future CH4 and N2O emissions of coastal wetlands in four sites along the latitude in China. The simulation results showed that different vegetation zones, including bare beach, Spartina beach, and Phragmites beach, produced different emissions of CH4 and N2O in the same latitude region. Correlation analysis indicated that vegetation types, water level, temperature, and soil organic carbon content are the main factors affecting emissions of CH4 and N2O in coastal wetlands. PMID:24892044

Liu, Yuhong; Wang, Lixin; Bao, Shumei; Liu, Huamin; Yu, Junbao; Wang, Yu; Shao, Hongbo; Ouyang, Yan; An, Shuqing

2014-01-01

98

[Characteristics of soil nematode communities in coastal wetlands with different vegetation types].  

PubMed

An investigation was conducted on the characteristics of soil nematode communities in different vegetation belts (Spartina alterniflora belt, Sa; Suaeda glauca belt, Sg; bare land, B1; Phragmites australis belt, Pa; and wheat land, Wl) of Yancheng Wetland Reserve, Jiangsu Province of East China. A total of 39 genera and 20 families of soil nematodes were identified, and the individuals of dominant genera and common genera occupied more than 90% of the total. The total number of the nematodes differed remarkably with vegetation belts, ranged from 79 to 449 individuals per 100 grams of dry soil. Wheat land had the highest number of soil nematodes, while bare land had the lowest one. The nematode ecological indices responded differently to the vegetation belts. The Shannon index (H) and evenness index (J) decreased in the order of Pa > Sg > Wl > Sa > Bl, and the dominance index (lambda) was in the order of Bl > Sa > Wl > Sg > Pa, suggesting that the diversity and stability of the nematode community in bare land were lower than those in the other vegetation belts, and the nematode community in the bare land tended to be simplified. The maturity index (MI) was higher in uncultivated vegetation belts than in wheat land, suggesting that the wheat land was disturbed obviously. The nematode community structure differed significantly with vegetation belts, and the main contributing species in different vegetation belts also differed. There existed significant correlations between the soil physical and chemical characteristics and the nematode numbers, trophic groups, and ecological indices. Our results demonstrated that the changes of soil nematode community structure could be used as an indicator well reflecting the diversity of vegetation belt habitat, and an important bio-indicator of coastal wetland ecosystem. PMID:23431791

Liu, Bei-Bei; Ye, Cheng-Long; Yu, Li; Jiao, Jia-Guo; Liu, Man-Qiang; Hu, Feng; Li, Hui-Xin

2012-11-01

99

The development of vegetative zonation patterns in restored prairie pothole wetlands  

Microsoft Academic Search

Summary 1. The spatial structure of plant communities can have strong impacts on ecosystem functions and on associated animal communities. None the less, spatial structure is rarely used as a measure of restoration success. 2. The restoration of hundreds of wetlands in the prairie pothole region in the mid-western USA provided an excellent opportunity to determine whether the re- establishment

Eric W. Seabloom; Arnold G. Van Der Valk

2003-01-01

100

Vegetation class dependent errors in lidar ground elevation and canopy height estimates in a boreal wetland environment  

Microsoft Academic Search

An airborne scanning light detection and ranging (lidar) survey using a discrete pulse return airborne laser terrain mapper (ALTM) was conducted over the Utikuma boreal wetland area of northern Alberta in August 2002. These data were analysed to quantify vegetation class dependent errors in lidar ground surface elevation and vegetation canopy surface height. The sensitivity of lidar-derived land-cover frictional parameters

Chris Hopkinson; Laura E. Chasmer; Gabor Sass; Irena F. Creed; Michael Sitar; William Kalbfleisch; Paul Treitz

2005-01-01

101

Soil Trace Gas Flux for Wetland Vegetation Zones in North Dakota Prairie Pothole Basins  

NASA Astrophysics Data System (ADS)

Wetland ecosystems are considered a source for radiatively trace gases [methane (CH4), carbon dioxide (CO2), nitrous oxide (N2O)] but flux data for these greenhouse gases are lacking for depressional wetlands that comprise the Prairie Pothole Region. This region is characterized by thousands of small, closed basins that extend along the Missouri Coteau from north central Iowa to central Alberta. Surrounding each body of water are conspicuous zonation patterns given by specific vegetation life-forms and soil properties that are predominately formed by basin hydrology. Basin vegetation zones include deep marsh, shallow marsh, wet meadow, low prairie, and cropland (Stewart and Kantrud,1971). Our primary objective was to determine if net greenhouse gas flux for soils in these wetland basins [mg/m2/day CO2 equivalent (IPCC, 2000)] vary with vegetative zone for prairie pothole ecosystems. These data may then be used to map estimates for total basin greenhouse gas (GHG) flux. Additionally, we aimed to find the relative contribution of each of the 3 trace gases (CO2, CH4 and N2O) to net GHG flux. We hypothesized that flux would be greatest for marsh areas and lowest for upland areas. We selected a semi-permenant prairie pothole research site in Max, ND and mapped respective vegetative zones for 3 adjacent basins. Sample points were randomly selected for each basin and zone using aerial imagery. Samples of soil gases were collected using the static chamber method on August 3, 2003, and these were analyzed using gas chromatography for CO2, CH4 and N2O the following day. Soil moisture, clay content, organic matter, and temperature data were also collected. Net greenhouse gas flux for the cropped zone soils was significantly lower (p<0.01) than flux for the deep marsh, shallow marsh and wet meadow zone soils. Average flux measurement by zone (mg CO2 equivalent/m2/day) was 283 for cropland, 677 for low prairie, 1067 for wet meadow, 2572 for shallow marsh, and 6686 for deep marsh. Methane, in terms of CO2 equivalents, contributed most strongly to and was the best predictor of greenhouse gas flux (r2=0.98). Since most of these basin areas are planted with wheat, average net GHG flux per square meter was 600 to 900 mg CO2 equivalents per day. Our results indicate that there are flux differences among wetland zones within these closed basin ecosystems and that CH4 contributes most to net GHG flux for these wetland soils.

Phillips, R. L.; Beeri, O.; Dekaiser, E. S.

2003-12-01

102

Development of vegetation in created wetlands in western Norway  

Microsoft Academic Search

The Myrkdalen lake, western Norway was subjected to a permanent 1.4 m drawdown in June 1987. After the drawdown, channels and artificial islands were constructed within the exposed floodplain system. Two permanent transects were established within this man-made environment, and these have been analyzed annually until 1995. The quadrats lie all on the same type of substrate, are at different

Arvid Odland

1997-01-01

103

Wind driven vertical transport in a vegetated, wetland water column with air-water gas exchange  

NASA Astrophysics Data System (ADS)

Flow around arrays of cylinders at low and intermediate Reynolds numbers has been studied numerically, analytically and experimentally. Early results demonstrated that at flow around randomly oriented cylinders exhibits reduced turbulent length scales and reduced diffusivity when compared to similarly forced, unimpeded flows (Nepf 1999). While horizontal dispersion in flows through cylinder arrays has received considerable research attention, the case of vertical dispersion of reactive constituents has not. This case is relevant to the vertical transfer of dissolved gases in wetlands with emergent vegetation. We present results showing that the presence of vegetation can significantly enhance vertical transport, including gas transfer across the air-water interface. Specifically, we study a wind-sheared air-water interface in which randomly arrayed cylinders represent emergent vegetation. Wind is one of several processes that may govern physical dispersion of dissolved gases in wetlands. Wind represents the dominant force for gas transfer across the air-water interface in the ocean. Empirical relationships between wind and the gas transfer coefficient, k, have been used to estimate spatial variability of CO2 exchange across the worlds’ oceans. Because wetlands with emergent vegetation are different from oceans, different model of wind effects is needed. We investigated the vertical transport of dissolved oxygen in a scaled wetland model built inside a laboratory tank equipped with an open-ended wind tunnel. Plastic tubing immersed in water to a depth of approximately 40 cm represented emergent vegetation of cylindrical form such as hard-stem bulrush (Schoenoplectus acutus). After partially removing the oxygen from the tank water via reaction with sodium sulfite, we used an optical probe to measure dissolved oxygen at mid-depth as the tank water re-equilibrated with the air above. We used dissolved oxygen time-series for a range of mean wind speeds to estimate the gas transfer coefficient, k, for both a vegetated condition and a control condition (no cylinders). The presence of cylinders in the tank substantially increased the rate of the gas transfer. For the highest wind speed, the gas transfer coefficient was several times higher when cylinders were present compared to when they were not. The gas transfer coefficient for the vegetated condition also proved sensitive to wind speed, increasing markedly with increasing mean wind speeds. Profiles of dissolved oxygen revealed well-mixed conditions in the bulk water column following prolonged air-flow above the water surface, suggesting application of the thin-film model is appropriate. The enhanced gas exchange observed might be explained by increased turbulent kinetic energy within the water column and the anisotropy of the cylinder array, which constrains horizontal motions more than vertical motions. Improved understanding of gas exchange in vegetated water columns may be of particularly use to investigations of carbon fluxes and soil accretion in wetlands. Reference: Nepf, H. (1999), Drag, turbulence, and diffusion in flow through emergent vegetation, Water Resour. Res., 35(2), 479-489.

Poindexter, C.; Variano, E. A.

2010-12-01

104

Establishment of vegetation on mined sites by management of mycorrhizae  

SciTech Connect

Plant ecosystems, including those in the tropical, temperate, boreal, and desert zones, began evolving more than 400 million years ago. Trees and other land plants in these environments were faced with many natural stresses including extreme temperature changes, fluctuating levels of available water, soil infertility, catastrophic fires and storms, poor soil physical conditions and competition. Basically, these plants evolved by genetic selection and developed many physical, chemical, and biological requirements necessary to survive these periodically stressed environments. Survivors were those that could form extensive lateral root systems to occupy soil volumes sufficiently large for them to obtain enough essential mineral elements and water to support their above and below ground growth needs. The most competitive plants in these stressed ecosystems were those with the largest root systems. One major biological requirement that evolved was the association of plants with mycorrhizal fungi. This is still true today for land that has been disturbed by mining, construction, and other activities. Successful vegetation establishment on these lands has been achieved by using the biological tools; native tree seedlings, shrubs, forbs, and grasses inoculated with specific, beneficial mycorrhizal fungi. Trees and shrubs are custom grown in nurseries with selected mycorrhizal fungi, such as Pisolithus tinctorius (Pt) and other fungi, provide significant benefits to the plants through increased water and mineral adsorption, decreased toxin absorption and overall reduction of plant stress. This has resulted in significant increases in plant growth and survival rates, density and sustainable vegetation.

Marrs, L.F.; Marx, D.H.; Cordell, C.E.

1999-07-01

105

Short-term responses of wetland vegetation after liming of an Adirondack watershed  

SciTech Connect

Watershed liming has been suggested as a long-term mitigation strategy for lake acidity, particularly in areas subject to high levels of acidic deposition. However, virtually no information has been available on the impacts of liming on wetland vegetation. In 1989, 1100 Mg of limestone (83.5% CaCO[sub 3]) were aerially applied to 48% (100 ha) of the Woods Lake watershed in the west-central Adirondack region of New York as part of the first comprehensive watershed liming study in North America. We inventoried wetland vegetation in 1.0-m[sup 2] plots before liming and during the subsequent 2 yr. Within this period liming influenced the cover, frequency, or importance values of only 6 of 64 wetland taxa. The cover of Sphagnum spp. and of the cespitose sedge Carex interior decreased in control relative to limed plots, and cover of the rhizomatous sedge Cladium mariscoides increased nearly threefold in limed areas. These two sedges, which are relatively tall, are characteristic of more calcareous habitats. Cover of the grass Muhlenbergia uniflora, cover and importance were adversely affected or inhibited by lime. It is unclear whether liming directly inhibited the growth of these three small-statured species, or whether the adverse effects of lime were mediated through shifts in competitive interactions with other species. The limited responses that we observed to liming, along with changes that occurred in control plots over the study period, may indicate that in the short term watershed liming was no more of a perturbation than the environmental factors responsible for natural annual variation in wetland communities.

Mackun, I.R.; Leopold, D.J.; Raynal, D.J. (State Univ. of New York, Syracuse, NY (United States))

1994-08-01

106

Vegetation influences on groundwater salinity and chemical heterogeneity in a freshwater, recharge floodplain wetland, South Africa  

NASA Astrophysics Data System (ADS)

SummaryKnowledge of wetland systems from sub-humid and semi-arid regions remains poor, particularly with regards to surface water-groundwater interactions. As a result of variable inflow and high evapotranspiration rates, such systems are often associated with the development of groundwater salinity. By focusing on the riparian species, Acacia xanthophloea, this study investigates the interaction between vegetation, groundwater, and occurrence of salinity on the Mkuze River floodplain, a seasonally dry, freshwater wetland. The relationship between groundwater chemistry and water table elevation suggests that these deep-rooted trees act as evapotranspirational pumps, selectively removing water and causing the subsurface concentration of solutes. Extensive root systems that reach the water table, coupled with high transpiration rates, result in local groundwater reaching electrical conductivities in excess of 20 mS/cm, approximately 15-20 times higher than those commonly found elsewhere on the floodplain. In this environment, these trees appear tolerant of salinities that would be toxic to most other plants. Plant tissue ion concentrations indicate that solute exclusion is the dominant means for avoidance of salt toxicity, with root turnover a possible regulatory mechanism. Data presented support our hypothesis that these trees exert feedback interactions on groundwater and sediment chemistry. Transpiration results not only in the development of saline groundwater, which is likely to influence vegetation distribution, but also initiates the precipitation of less soluble minerals, such as CaCO 3 and SiO 2, which have the potential to modify sediment pH, hydraulic conductivity, and landscape topography. Spatial variation in chemical processing is thus likely to play a role in creating and maintaining habitat diversity on the floodplain. Wetlands in semi-arid and sub-humid regions are often susceptible to shallow groundwater chemical transformations due to seasonal or episodic inflows and higher evapotranspiration demand. The documentation of solute concentration and retention in wetland systems from a variety of semi-arid and sub-humid areas suggests that evapotranspiration-driven processes may be more widespread than is currently understood. In environments where evapotranspiration plays an important role in the overall water budget of a wetland, similar vegetation-groundwater interactions and chemical processes are likely to occur. Recognition of broad differences between such systems and those of their better studied counterparts in tropical and temperate regions makes it necessary to develop a greater understanding of these processes.

Humphries, Marc S.; Kindness, Andrew; Ellery, William N.; Hughes, Jeffrey C.; Bond, Jonathan K.; Barnes, Kirsten B.

2011-12-01

107

Submerged aquatic vegetation-based treatment wetlands for removing phosphorus from agricultural runoff: response to hydraulic and nutrient loading  

Microsoft Academic Search

Submerged aquatic vegetation (SAV) communities exhibit phosphorus (P) removal mechanisms not found in wetlands dominated by emergent macrophytes. This includes direct assimilation of water column P by the plants and pH-mediated P coprecipitation with calcium carbonate (CaCO3). Recognizing that SAV might be employed to increase the performance of treatment wetlands, we investigated P removal in mesocosms (3.7m2) stocked with a

F. E. Dierberg; T. A. DeBusk; S. D. Jackson; M. J. Chimney; K. Pietro

2002-01-01

108

COMPARISON OF LEVELS OF SULFOLANE AND DIISOPROPANOLAMINE IN NATURAL WETLAND VEGETATION EXPOSED TO GAS-CONDENSATE CONTAMINATED GROUND WATER  

Microsoft Academic Search

Groundwater containing the process chemicals sulfolane (tetrahydrothiophene 1,1-dioxide) and diisopropanolamine (DIPA) has contaminated a wetland in the vicinity of a sour-gas natural gas processing facility. Of concern is the extent of which these contaminants are taken up by vegetation and the associated risk to wildlife that may eat the plants. All sampled wetland plants contained detectable levels of sulfolane and

John V. Headley; Leslie C. Dickson; Kerry M. Peru

2002-01-01

109

Effects of hydraulic resistance by vegetation on stage dynamics of a stormwater treatment wetland  

NASA Astrophysics Data System (ADS)

SummaryThis work examined the potential effects of large-scale thinning of emergent vegetation on the stage dynamics in a very large (33.3 km2) constructed treatment wetland in South Florida. Dense vegetative biomass in treatment wetlands may restrict water flow and increase water levels, which may in turn have adverse effects on vegetative community structure. Here, we developed a physically-based, spatially-distributed hydrodynamic model of Stormwater Treatment Area 2, Cell 2 (STA2C2) to investigate the spatio-temporal variability of water level (stage) in response to management for thinning of emergent macrophytes (e.g., burning and/or herbicide treatments). The model was calibrated against stage measured at six monitoring stations for 1 year, and subsequently validated against 2 years of stage data from eight stations. Finally, the validated model was extended to simulate various vegetation management scenarios. The model provided an excellent fit to observed stage data in both calibration and validation periods (median model efficiency indices of 0.82 and 0.83, respectively). Higher stages in the treatment cell were dominantly associated with peak inflow magnitude and the timing of event intervals. Prolonged periods of sustained deep water conditions were observed when one flow peak was followed by consecutive peaks. A gradual stage gradient from the inlet to outlet was observed during peak flow periods, with a shift to a sharp gradient at approximately two-thirds distance from the inlet. Stages in the wetland were found to be controlled less by the hydraulic resistance, as indicated by a low sensitivity of simulated water levels for a ±50% perturbation in flow resistance parameter. Water depths were reduced by a maximum of 12 cm at the inlet region by thoroughly thinning the remaining emergent vegetation in STA2C2. Similarly, a maximum of only 2% of the total STA2C2 area was prevented from exceeding a water depth believed to be detrimental to Typha sp. (1.22 m) after the highest peak inflow. Collectively, our findings suggested that vegetation thinning may not be effective for minimizing deep water conditions in STA2C2.

Paudel, Rajendra; Grace, Kevin A.; Galloway, Stacey; Zamorano, Manuel; Jawitz, James W.

2013-03-01

110

Thirteen years of wetland vegetation succession following a permanent drawdown, Myrkdalen Lake, Norway  

Microsoft Academic Search

Myrkdalen Lake in Western Norway was subjected to a 1.4 mdrawdown in June 1987. Plant establishment and vegetation succession on theexposed sediments of a fluvial delta plain was monitored through 2000. Theinvestigated area extended from the original Equisetumfluviatile zone to the new lake edge. The substrate was homogeneousand consisted mainly of minerogenous fluvial sediments. Vegetation data weresampled within continuous quadrats

Arvid Odland; Roger del Moral

2002-01-01

111

7 CFR 1410.11 - Farmable Wetlands Program.  

Code of Federal Regulations, 2013 CFR

...the maximum extent possible, as determined by CCC, in accordance with NRCS FOTG including, as appropriate, restoring the hydrology of the wetland and establishing vegetative cover (which may include emerging vegetation in water and bottomland...

2013-01-01

112

7 CFR 1410.11 - Farmable Wetlands Program.  

...the maximum extent possible, as determined by CCC, in accordance with NRCS FOTG including, as appropriate, restoring the hydrology of the wetland and establishing vegetative cover (which may include emerging vegetation in water and bottomland...

2014-01-01

113

7 CFR 1410.11 - Farmable Wetlands Program.  

Code of Federal Regulations, 2011 CFR

...the maximum extent possible, as determined by CCC, in accordance with NRCS FOTG including, as appropriate, restoring the hydrology of the wetland and establishing vegetative cover (which may include emerging vegetation in water and bottomland...

2011-01-01

114

7 CFR 1410.11 - Farmable Wetlands Program.  

Code of Federal Regulations, 2012 CFR

...the maximum extent possible, as determined by CCC, in accordance with NRCS FOTG including, as appropriate, restoring the hydrology of the wetland and establishing vegetative cover (which may include emerging vegetation in water and bottomland...

2012-01-01

115

7 CFR 1410.11 - Farmable Wetlands Program.  

Code of Federal Regulations, 2010 CFR

...the maximum extent possible, as determined by CCC, in accordance with NRCS FOTG including, as appropriate, restoring the hydrology of the wetland and establishing vegetative cover (which may include emerging vegetation in water and bottomland...

2010-01-01

116

Wetland soil and vegetation bismuth content following experimental deposition of bismuth pellets.  

PubMed

Bismuth pellets have been approved as a non-toxic alternative to lead pellets in Canada since 1997 but, to our knowledge, there is little literature for soil and vegetation bismuth content in areas of bismuth pellet deposition. The present study addresses this shortcoming by measuring wetland soil and vegetation bismuth content following experimental deposition of bismuth pellets under ambient and experimentally increased acidic deposition conditions. We manipulated 24 plots in a fully factorial design (bismuth shot x soil acidification) in a south-eastern Ontario freshwater wetland during 1999-2003. Soil pH (range 6.5-7.3) increased significantly (p = 0.001) during the experimental period but there were no significant differences amongst treatments (p = 0.79). Significantly (p < 0.05) greater bismuth concentrations were measured in soil receiving bismuth pellets (mean +/- SE, n = 6; with acidification = 2.55 +/- 1.02 microg Bi g(-1) dry mass [DM]; without acidification = 6.40 +/- 2.23 microg Bi g(-1) DM) compared to plots that were not seeded with bismuth pellets (without acidification = 0.42 +/- 0.09 microg Bi g(-1) DM; with acidification = 0.39 +/- 0.10 microg Bi g(-1) DM). Nevertheless, bismuth levels in 20 of 24 aboveground tissue samples from the Carex lacustris-Agrostis scabra community were below detection levels (0.057 microg Bi g(-1) DM); the other samples ranged from 0.065 to 0.095 microg Bi g(-1) DM, similar to global background levels. Primary productivity in plots receiving bismuth pellets and soil acidification was not significantly (p = 0.15) different to vegetation in plots that were not manipulated. The results suggest bismuth mobilization from bismuth pellets into soil but not to aboveground vegetation. PMID:18688464

Fahey, Nathan S C; Karagatzides, Jim D; Jayasinghe, Ruwan; Tsuji, Leonard J S

2008-08-01

117

Direct and Indirect Effects of Vegetation on Methylmercury Production in Wetlands as Assessed by Experimental Plant Removal  

NASA Astrophysics Data System (ADS)

Although vegetated wetlands are among the most active habitats for microbial methylmercury (MeHg) production, the relative influence of wetland vegetation itself is poorly understood. Plant physiology and biomass (live and dead) can modify both microbial populations and inorganic mercury (Hg(II)) bioavailability through a number of soil, water and atmospheric interactions. Alternatively, plant activity and structure can be simply a response to geochemical conditions that also favor Hg(II)-methylation. Linked studies within the San Francisco Bay watershed have demonstrated that habitat-specific biogeochemical characteristics are the dominant factors controlling MeHg production, and that differences in wetland plant biomass, root density, decomposition rates, can directly influence sediment mercury cycling. A vegetated:de-vegetated paired plot approach was used to directly assess the influence of live plant activities on surface sediment mercury dynamics and associated biogeochemistry in differing wetland settings: salt marshes, permanent and seasonal freshwater wetlands, a freshwater floodplain, and agricultural rice fields. Although results from several of these subhabitats are pending, the data thus far have illustrated linkages between wetland plants and microbial Hg(II)-methylation. De- vegetation strongly influenced sediment biogeochemistry (e.g. redox, dissolved organic content, and reduced sulfur pools) in high interior pickleweed (Sarcocornia pacifica) dominated saltmarshes, where the high rates of MeHg production (up to 1 ng g-1dry sed d-1) observed in vegetated plots were reduced to <10 pg g-1dry sed d-1 in de-vegetated plots. Further, plant root densities were positively correlated with the activity of Hg(II)-methylating bacteria in these interior saltmarsh settings. The pool size of mercury available for methylation ("reactive mercury") was not measurably influenced by this short-term de-vegetation experiment, but across field studies, rhizosphere biomass was often negatively correlated with reactive mercury concentration due to a corresponding increase in solid-phase reduced-sulfur compounds associated with this zone. Because mercury methylation is controlled by both the reactive mercury pool size and the microbial Hg(II)-methylation activity, the direct influence of wetland plants on both of these terms can be profound and reflect multiple, and potentially contrasting, mercury cycling pathways. Experimental field manipulations, in conjunction with comparative habitat and process studies, represent essential tools to elucidate the influence of wetland plant communities on Hg cycling.

Windham-Myers, L.; Marvin-Dipasquale, M.

2007-12-01

118

[Study on nutrient and salinity in soil covered with different vegetations in Shuangtaizi estuarine wetlands].  

PubMed

Nutrient elements and salinity in soil covered by different vegetations including Phragmites australis (Clay.) Trin., Typha orientalis Presl., Puccinellia distans Parl, and Suaeda salsa in Shuangtaizi estuarine wetlands were investigated to study their distribution characteristics and to reveal the nutrient element variation during the vegetation succession processes. Results indicated that total potassium, total phosphorus and salinity were different significantly in soil between different plant communities while available phosphorus, total nitrogen, available nitrogen, available potassium, total sulfur, iron and soil organic carbon were different insignificantly. Correlation analysis suggested that soil organic carbon were related significantly to total nitrogen, available phosphorus, available potassium, which implied that decomposition of plant litter might be the mail source of soil nitrogen and available nutrient. Salinity was significantly related to total phosphorus and iron in soil. In Shuangtaizi estuarine wetland soil, ratios of carbon to nitrogen (R(C/N)) was in the range of 12.21-26.33 and the average value was 18.21, which was higher than 12.0. It indicated that soil organic carbon in Shuangtaizi estuarine mainly came from land but not ocean and plants contributed the most of soil organic matters. There was no significant difference in R(C/N) between soil from the four plant communities (F = 1.890, p = 0.151). R(C/N) was related significantly to sol salinity (r = 0.346 3, p = 0.035 8) and was increasing with soil salinity. PMID:22165232

Song, Xiao-Lin; Lü, Xian-Guo; Zhang, Zhong-Sheng; Chen, Zhi-Ke; Liu, Zheng-Mao

2011-09-01

119

Development and testing the hydrological dynamics of vegetated wetland for CLM  

NASA Astrophysics Data System (ADS)

Northern peatlands store ~ 30% of the global soil carbon, though only representing ~ 3% of the Earth's land surface. Community Land Model (CLM) component of the Community Earth System Model (CESM) doesn't currently represent vegetated wetlands. To address this limitation, we incorporate key structural and process changes in the CLM. The model with new modifications will be informed and tested by Spruce and Peatland Responses Under Climatic and Environmental Change Experiment (SPRUCE). Our initial efforts have focused on model modifications needed to represent the isolated hydrologic cycle of the bog environment, as well as the observed patterning of the bog interior into raised hummocks and sunken hollows having distinct hydrologic dynamics and vegetation communities. The preliminary results of the hydrologic efforts show that the simulated water table heights for hummocks and hollows are consistent with observations, and the projected seasonal water table heights for the hummock/hollow topography are reasonable. Next steps for CLM-wetlands modeling are to calibrate the new hydrology treatment with vertically structured soil and CH4 sub-model, and to introduce Sphagnum hydrology and carbon cycle physiology. The comparison of CLM simulated and observed water table heights for year 2011 and 2012

Shi, X.; Thornton, P. E.; Ricciuto, D. M.; Hanson, P. J.; Mao, J.

2013-12-01

120

The influence of vegetation on sedimentation and resuspension of soil particles in small constructed wetlands.  

PubMed

When initiatives to mitigate soil erosion are insufficient or fail, constructed surface flow wetlands (CWs) could be a final buffer to reduce pollution before reaching recipients. The objective of this study was to determine the influence of CW vegetation on the retention of soil particles from arable land. Retention was measured with water flow-proportional sampling systems in the inlet and outlet, sedimentation traps, and sedimentation plates in four small CWs over a period of 5 yr. The surface area of the CWs was 265 to 900 m2, and the average hydraulic loads were 1.2 to 3.4 m d(-1). Watershed areas were 0.5 to 1.5 km2. Annual soil particle retention was 30 to 80% or 14 to 121 kg m(-2). Results show that macrophytes stimulate sediment retention by mitigating resuspension of CW sediment. Five years after construction, resuspension had decreased approximately 40% and was negligible. As vegetation cover increases, the influence of macrophytes on soil particle retention reaches a level where other factors, such as hydraulic load and sediment load, were more important. Macrophytes increased the hydraulic efficiency by reducing short-circuit or preferential flow. However, vegetation did not have any influence on the clay concentration in the sediment. Hence, a possible stimulation of particle flocculation was not detected. Vegetation makes it possible to use the positive effect of a short particle settling distance in shallow ponds by hindering resuspension. PMID:11476524

Braskerud, B C

2001-01-01

121

Wetlands.  

ERIC Educational Resources Information Center

Suggests studying New York's wetlands, both in the classroom and in the field, to illustrate ecological concepts of diversity, succession, and adaptation and to learn about their importance in controlling flooding, erosion, and pollution. (NEC)

Nelson, Patricia L.

1986-01-01

122

Recent Trends in Satellite Vegetation Index Observations Indicate Decreasing Vegetation Biomass in the Southeastern Saline Everglades Wetlands  

NASA Astrophysics Data System (ADS)

We analyzed trends in time series of the normalized difference vegetation index (NDVI) from multitemporal satellite imagery for 2001-2010 over the southeastern Everglades where major changes in vegetation structure and type have been associated with sea-level rise and reduced freshwater flow since the 1940s. Non-parametric trend analysis using the Theil-Sen slope revealed that 84.4% of statistically significant trends in NDVI were negative, mainly concentrated in scrub mangrove, sawgrass (Cladium jamaicense) and spike rush (Eleocharis cellulosa) communities within 5 km of the shoreline. Observed trends were consistent with trends in sawgrass biomass measurements made from 1999-2010 in three Long-term Ecological Research (LTER) sites within our study area. A map of significant trends overlaid on a RapidEye high-resolution satellite image showed large patches of negative trends parallel to the shoreline in and around the 'white zone,' which corresponds to a low-productivity band that has moved inland over the past 70 years. Significantly positive trends were observed mainly in the halophytic prairie community where highly salt tolerant species are typically found. Taken as a whole, the results suggest that increased saline intrusion associated with sea-level rise continues to reduce the photosynthetic biomass within freshwater and oligohaline marsh communities of the southeastern Everglades. Trends in 2001-2010 NDVI in southern saline Everglades wetlands of South Florida. a) slope values; b) areas of significant slope; c) location of the study area.

Fuller, D. O.

2013-12-01

123

Accounting for non-photosynthetic vegetation in remote-sensing-based estimates of carbon flux in wetlands  

USGS Publications Warehouse

Monitoring productivity in coastal wetlands is important due to their high carbon sequestration rates and potential role in climate change mitigation. We tested agricultural- and forest-based methods for estimating the fraction of absorbed photosynthetically active radiation (f APAR), a key parameter for modelling gross primary productivity (GPP), in a restored, managed wetland with a dense litter layer of non-photosynthetic vegetation, and we compared the difference in canopy light transmission between a tidally influenced wetland and the managed wetland. The presence of litter reduced correlations between spectral vegetation indices and f APAR. In the managed wetland, a two-band vegetation index incorporating simulated World View-2 or Hyperion green and near-infrared bands, collected with a field spectroradiometer, significantly correlated with f APAR only when measured above the litter layer, not at the ground where measurements typically occur. Measures of GPP in these systems are difficult to capture via remote sensing, and require an investment of sampling effort, practical methods for measuring green leaf area and accounting for background effects of litter and water.

Schile, Lisa M.; Byrd, Kristin B.; Windham-Myers, Lisamarie; Kelly, Maggi

2013-01-01

124

Controls on vegetative flow resistance in wetlands and low-gradient floodplains  

NASA Astrophysics Data System (ADS)

In low-gradient floodplains and wetlands, vegetation provides the primary resisting force for flow and hence can exert strong influence on flow velocities, water depth, and redistribution of sediments that affect the geomorphic evolution and ecological function of wetland landscapes. Critical research needs that remain for predicting flow in these environments include integration of data over multiple temporal and spatial scales as well as improved methods of estimating flow resistance. Existing relationships predict flow resistance as a function of stem diameter (d) and frontal area (a). Since these flow resistance parameters are difficult to quantify and generally not measured in the field, large-scale estimation of flow resistance requires a suitable proxy measurement that can be directly related to these parameters. Biomass is a parameter commonly obtained in field surveys and from remote sensing data. We use biomass to predict frontal area and stem diameter using empirical relations for vegetation quadrat data collected in the Everglades (Florida, USA). Biomass is directly related to frontal area (a) through a power function. This is generally true across various plant communities, but the relationship is strongest within individual plant communities. Biomass is linearly related to stem diameter (d) and biovolume (ad) in a manner independent of plant community. We found that species diversity, plant community, water depth, phosphorus concentration, and seasonality are important in governing the spatial and temporal variations in flow resistance parameters, specifically stem diameter and biovolume, as well as plant tissue density. We correlate unstratified quadrat biomass estimates to a remote sensing parameter, normalized difference vegetation index (NDVI), to address implications for scaling up quadrat data for integration into landscape-level processes. These results will improve parameterization of flow resistance for ongoing hydrologic modeling efforts, which will ultimately guide future restoration efforts in the heavily managed and degraded Everglades landscape.

Skalak, K.; Harvey, J. W.; Larsen, L. G.; Noe, G. B.; Rybick, N.; Jones, J.

2010-12-01

125

Effects of sediment removal on vegetation communities in Rainwater Basin playa wetlands.  

PubMed

Sedimentation from cultivated agricultural land use has altered the natural hydrologic regimes of depressional wetlands in the Great Plains. These alterations can negatively affect native wetland plant communities. Our objective was to determine if restored wetlands are developing plant communities similar to reference wetland conditions following hydrologic restoration. For this study, hydrology was restored via sediment removal. Thirty-four playa wetlands in reference, restored, and agricultural condition within the Rainwater Basin Region of Nebraska were sampled in 2008 and 2009. In 2008, reference and restored wetlands had higher species richness and more native, annual, and perennial species than agricultural wetlands. Restored wetlands had similar exotic species richness compared to reference and agricultural wetlands; however, reference wetlands contained more than agricultural wetlands. Restored wetlands proportion of exotics was 3.5 and 2 times less than agricultural wetlands and reference wetlands respectively. In 2009, reference and restored wetlands had higher species richness, more perennial species, and more native species than agricultural wetlands. Restored wetlands contained a greater number and proportion of annuals than reference and agricultural wetlands. Canonical Correspondence Analysis showed that reference, restored, and agricultural wetlands are dominated by different plant species and guilds. Restored wetland plant communities do not appear to be acting as intermediates between reference and agricultural wetland conditions or on a trajectory to reach reference conditions. This may be attributed to differing seed bank communities between reference and restored wetlands, dispersal limitations of perennial plant guilds associated with reference wetland conditions, and/or management activities may be preventing restored wetlands from reaching reference status. PMID:23786876

Beas, Benjamin J; Smith, Loren M; LaGrange, Theodore G; Stutheit, Randy

2013-10-15

126

Seed-bank and vegetation development in a created tidal freshwater wetland on the Delaware River, Trenton, New Jersey, USA  

Microsoft Academic Search

The initial stages of seed-bank and vegetation development were documented in a newly created tidal freshwater wetland where\\u000a donor soils were not applied. The 32.3-ha site adjacent to the Delaware River in New Jersey, USA was completed in stages from\\u000a November 1993 to November 1994. Objectives of the study were to determine characteristics of the seed bank and vegetation\\u000a and

Mary Allessio Leck

2003-01-01

127

A test of vegetation-related indicators of wetland quality in the prairie pothole region  

USGS Publications Warehouse

This study was part of an effort by the U.S. Environmental Protection Agency to quantitatively assess the environmental quality or 'health' of wetland resources on regional and national scales. During a two-year pilot study, we tested selected indicators of wetland quality in the U.S. portion of the prairie pothole region (PPR). We assumed that the amount of cropland versus non-cropland (mostly grassland) in the plots containing these basins was a proxy for their quality. We then tested indicators by their ability to discriminate between wetlands at the extremes of that proxy. Amounts of standing dead vegetation were greater in zones of greater water permanence. Depth of litter was greater in zones of greater water permanence and in zones of basins in poor-quality watersheds. Amounts of unvegetated bottom were greater in basins in poor-quality watersheds; lesser amounts occurred in all wetlands during a wetter year. Greater amounts of open water occurred during a wetter year and in zones of greater water permanence. When unadjusted for areas (ha) of communities, plant taxon richness was higher in wet-meadow and shallow-marsh zones in good-quality watersheds than in similar zones in poor-quality watersheds. Wet-meadow zones in good-quality watersheds had greater numbers of native perennials than those in poor-quality watersheds. This relation held when we eliminated all communities in good-quality watersheds larger than the largest communities in poor-quality watersheds from the data set. We conclude that although amounts of unvegetated bottom and plant taxon richness in wet-meadow zones were useful indicators of wetland quality during our study, the search for additional such indicators should continue. The value of these indicators may change with the notoriously unstable hydrological conditions in the PPR. Most valuable would be indicators that could be photographed or otherwise remotely sensed and would remain relatively stable under various hydrological conditions. An ideal set of indicators could detect the absence of stressors, as well as the presence of structures or functions, of known value to major groups of organisms.

Kantrud, H. A.; Newton, W. E.

1996-01-01

128

Integrating multi-temporal spectral and structural information to map wetland vegetation in a lower Connecticut River tidal marsh  

E-print Network

: Coastal wetlands Image classification LiDAR Phragmites australis QuickBird Spectroradiometer Vegetation variability of the dominant marsh plant species, Spartina patens, Phragmites australis and Typha spp-native genotype of Phragmites australis (Cav.) Trin. ex Steud (common reed) in Connecticut marshes (Barrett

Royer, Dana

129

Establishment of microscale vegetation pattern in maritime chaparral after fire  

Microsoft Academic Search

We quantified microscale pattern in vegetation and seed assemblages along a 24 m transect before and for two years following a controlled burn in chamise (Adenostoma fasciculatum) chaparral in central coastal California. Our objective was to document scale-dependent correlation between pre-burn seed assemblages, pre-burn canopy cover, microtopography, soil temperatures during burning, post-burn seed assemblages and post-burn vegetation. Scale-dependent correlations among

Frank W. Davis; Mark I. Borchert; Dennis C. Odion

1989-01-01

130

[Effects of soil factors on vegetation community structure in an abandoned subtropical paddy wetland].  

PubMed

Based on the investigation data from a subtropical wetland having been abandoned from paddy agriculture for one year, a redundancy analysis was conducted on the relationships between vegetation community and soil factors in the wetland. It was found that soil moisture regime, available K and P, and pH were the main factors affecting the distribution of plant species. The common plant species could be classified into three groups, i. e., Ludwigia prostrata - Murdannia triquetra group (G1), Hemarthria altissima - Rotala rotundifolia - Lapsana apogonoides group (G2), and Conyza canadensis - Polygonum hydropiper - Paspalum pasaloides group (G3). G1 mainly distributed on the soils with higher available K, G2 mainly distributed in periodically flooded area, while G3 mainly distributed in drainage area and was positively correlated to soil available P and pH. Species diversity and above-ground biomass had significant positive correlations with soil pH and total K, respectively, while evenness index was significantly negatively correlated with soil available N. No significant correlations were observed among other indices. PMID:19899449

Peng, Yi; Li, Yu-Yuan; Li, Zhong-Wu; Ye, Fang-Yi; Pan, Chun-Xiang; Xie, Xiao-Li

2009-07-01

131

CHANGES IN THE VEGETATION COVER IN A CONSTRUCTED WETLAND AT ARGONNE NATIONAL LABORATORY, ILLINOIS  

Microsoft Academic Search

Wetlands are valuable resources that are disappearing at an alarming rate. Land development has resulted in the destruction of wetlands for approximately 200 years. To combat this destruction, the federal government passed legislation that requires no net loss of wetlands. The United States Army Corps of Engineers (USACE) is respon- sible for regulating wetland disturbances. In 1991, the USACE determined

COURTNEY LYNN BERGMAN; KIRK LAGORY

132

Regeneration of vegetation on wetland crossings for gas pipeline rights-of-way one year after construction  

SciTech Connect

Four wetland crossings of gas pipeline rights-of-way (ROWs), located in Florida, Michigan, New Jersey, and New York, were surveyed for generation of vegetation roughly one year after pipeline construction was completed. Conventional trench-and-fill construction techniques were employed for all four sites. Estimated areal coverage of each species by vegetative strata within transect plots was recorded for plots on the ROW and in immediately adjacent wetlands undisturbed by construction activities. Relative success of regeneration was measured by percent exposed soil, species diversity, presence of native and introduced species, and hydric characteristics of the vegetation. Variable site factors included separation and replacement of topsoil, final grading of the soil, application of seed and fertilizer, and human disturbance unrelated to construction. Successful regeneration exhibited greater dependency on the first three factors listed.

Shem, L.M.; Zimmerman, R.E.; Zellmer, S.D. [Argonne National Lab., IL (United States); Van Dyke, G.D. [Trinity Christian Coll., Palos Heights, IL (United States). Dept. of Biology; Rastorfer, J.R. [Chicago State Univ., IL (United States). Dept. of Biological Sciences

1993-10-01

133

Monitoring rapid vegetation succession in estuarine wetland using time series MODIS-based indicators: An application in the Yangtze River Delta area  

Microsoft Academic Search

Frequent and continuous time series is required for the detection of plant phenology and vegetation succession. The launch of novel remote sensor MODIS (moderate resolution imaging spectroradiometer) provided us with an opportunity to make a new trial of studying the rapid vegetation succession in estuarine wetlands. In this study, the spatiotemporal variations of vegetation cover and tidal flat elevation along

Bin Zhao; Yaner Yan; Haiqiang Guo; Meimei He; Yongjian Gu; Bo Li

2009-01-01

134

Patch-Scale Effects of Equine Disturbance on Arthropod Assemblages and Vegetation Structure in Subalpine Wetlands  

NASA Astrophysics Data System (ADS)

Assessments of vertebrate disturbance to plant and animal assemblages often contrast grazed versus ungrazed meadows or other larger areas of usage, and this approach can be powerful. Random sampling of such habitats carries the potential, however, for smaller, more intensely affected patches to be missed and for other responses that are only revealed at smaller scales to also escape detection. We instead sampled arthropod assemblages and vegetation structure at the patch scale (400-900 m2 patches) within subalpine wet meadows of Yosemite National Park (USA), with the goal of determining if there were fine-scale differences in magnitude and directionality of response at three levels of grazing intensity. Effects were both stronger and more nuanced than effects evidenced by previous random sampling of paired grazed and ungrazed meadows: (a) greater negative effects on vegetation structure and fauna in heavily used patches, but (b) some positive effects on fauna in lightly grazed patches, suggested by trends for mean richness and total and population abundances. Although assessment of disturbance at either patch or landscape scales should be appropriate, depending on the management question at hand, our patch-scale work demonstrated that there can be strong local effects on the ecology of these wetlands that may not be detected by comparing larger scale habitats.

Holmquist, Jeffrey G.; Schmidt-Gengenbach, Jutta; Ballenger, Elizabeth A.

2014-06-01

135

A numerical study of vegetation impact on reducing storm surge by wetlands in a semi-enclosed estuary  

USGS Publications Warehouse

Coastal wetlands play a unique role in extreme hurricane events. The impact of wetlands on storm surge depends on multiple factors including vegetation, landscape, and storm characteristics. The Delft3D model, in which vegetation effects on flow and turbulence are explicitly incorporated, was applied to the semi-enclosed Breton Sound (BS) estuary in coastal Louisiana to investigate the wetland impact. Guided by extensive field observations, a series of numerical experiments were conducted based on variations of actual vegetation properties and storm parameters from Hurricane Isaac in 2012. Both the vegetation-induced maximum surge reduction (MSR) and maximum surge reduction rate (MSRR) increased with stem height and stem density, and were more sensitive to stem height. The MSR and MSRR decreased significantly with increasing wind intensity. The MSRR was the highest with a fast-moving weak storm. It was also found that the MSRR varied proportionally to the expression involving the maximum bulk velocity and surge over the area of interest, and was more dependent on the maximum bulk surge. Both MSR and MSRR appeared to increase when the area of interest decreased from the whole BS estuary to the upper estuary. Within the range of the numerical experiments, the maximum simulated MSR and MSRR over the upper estuary were 0.7 m and 37%, respectively.

Kelin, Hu; Qin, Chen; Wang, Hongqing

2014-01-01

136

Changes in vegetative coverage of the Hongze Lake national wetland nature reserve: a decade-long assessment using MODIS medium-resolution data  

NASA Astrophysics Data System (ADS)

Wetlands are important ecosystems on Earth. However, global wetland coverage is being reduced due to both anthropogenic and natural effects. Thus, assessment of temporal changes in vegetative coverage, as a measure of the wetland health, is critical to help implement effective management plans and provide inputs for climate-related research. In this work, 596 moderate-resolution imaging spectroradiometer (MODIS) 250-m resolution images of the Hongze Lake national wetland nature reserve from 2000 to 2009 were used to study the vegetative coverage (above the water surface) of the reserve. Three vegetation indices [normalized difference vegetation index (NDVI), enhanced VI (EVI), and floating algae index (FAI)] were compared to evaluate their effectiveness in assessing relative changes. FAI was less sensitive than NDVI and EVI to aerosol effects and showed less statistical error than NDVI and EVI. Long-term FAI data revealed clear seasonal cycles in vegetative coverage in the 113-km2 core area of the reserve, with annual maximal coverage relatively stable after 2004. This suggests that the national wetland nature reserve was well protected through the study period. However, vegetative coverage decreased due to the flooding event in 2003. Moreover, correlation analysis showed that annual sunshine duration collectively played a significant role in affecting the wetland vegetative coverage.

Yu, Kun; Hu, Chuanmin

2013-01-01

137

Prototype Application of NASA Missions to Identify Patterns of Wetland Vegetation Development within the South San Francisco Bay Salt Ponds  

NASA Astrophysics Data System (ADS)

The South Bay Salt Pond Restoration Project is the largest tidal wetland restoration on the west coast of the United States. Monitoring vegetation development in these emergent habitats with remote sensing can provide restoration managers with an indication of ecological health and progress of development. Remotely sensed imagery was used to monitor vegetation development and to map vegetation patterns and biota changes historically, during, and after salt pond construction for ponds A19, A20, and A21. Percent vegetative cover was mapped using the Normalized Difference Vegetation Index (NDVI) from MODIS, Tasseled Cap Greenness (TCG) and NDVI from Landsat TM, and the Ratio Vegetation Index (RVI) from ASTER. Field parameters included in-situ measurements and geographic locations for percent vegetative cover, and site specific species information. Field data were incorporated into GIS, and vegetation was analyzed using spatial statistics methods and a qualitative post-classification comparison technique. NDVI values obtained from the Landsat scenes indicated a net gain of 3.35 acres of vegetation cover from February 2006 (before pond breaching) to August 2009 for pond A21 and 1.33 acres and 3.14 acres for ponds A20 and A19, respectively. Increases in vegetation indicate the marsh has built up to a steady-state condition to provide appropriate habitat for endangered plant and animal species and also indicates the success of restoration practices.

Hsu, W.; Newcomer, M. E.; Justice, E.; Guild, L. S.; Skiles, J. W.

2010-12-01

138

Vegetation effects on floating treatment wetland nutrient removal and harvesting strategies in urban stormwater ponds.  

PubMed

Floating treatment wetlands (FTWs) consist of emergent macrophytes that are placed on a floating mat in a pond for water treatment and aesthetic purposes. FTWs may have unique advantages with respect to treating urban runoff within existing retention ponds for excess nutrients. However, research is lacking in providing guidance on performance of specific species for treating urban runoff, and on timing of harvest. Harvesting is needed to remove nutrients permanently from the retention pond. We investigated vegetation effects on FTWs on nitrogen (N) and phosphorus (P) removal performance and storage in above-ground FTW macrophyte tissues. The study evaluated pickerelweed (PW, Pontederia cordata L.) and softstem bulrush (SB, Schoenoplectus tabernaemontani) over time in microcosms flushed with water obtained from a nearby urban retention pond in northern Virginia near Washington, DC. While the literature exhibits a wide range of experimental sizes, using the term mesocosm, we have chosen the term microcosm to reflect the small size of our vessel; and do not include effects of sediment. The experiment demonstrated PW outperformed SB for P and N removal. Based upon analysis of the accumulated nutrient removal over time, a harvest of the whole PW and SB plants in September or October is recommended. However, when harvesting only the aerial parts, we recommend harvesting above-ground PW tissues in July or August to maximize nutrient removal. This is because PW translocates most of its nutrients to below-ground storage organs in the fall, resulting in less nutrient mass in the above-ground tissue compared to the case in the summer (vegetative stage). Further research is suggested to investigate whether vegetation can be overly damaged from multiple harvests on an annual basis in temperate regions. PMID:25214393

Wang, Chih-Yu; Sample, David J; Bell, Cameron

2014-11-15

139

Hydrologic, vegetation, and soil data collected in selected wetlands of the Big River Management area, Rhode Island, from 2008 through 2010  

USGS Publications Warehouse

The Rhode Island Water Resources Board planned to develop public water-supply wells in the Big River Management Area in Kent County, Rhode Island. Research in the United States and abroad indicates that groundwater withdrawal has the potential to affect wetland hydrology and related processes. In May 2008, the Rhode Island Water Resources Board, the U.S. Geological Survey, and the University of Rhode Island formed a partnership to establish baseline conditions at selected Big River wetland study sites and to develop an approach for monitoring potential impacts once pumping begins. In 2008 and 2009, baseline data were collected on the hydrology, vegetation, and soil characteristics at five forested wetland study sites in the Big River Management Area. Four of the sites were located in areas of potential drawdown associated with the projected withdrawals. The fifth site was located outside the area of projected drawdown and served as a control site. The data collected during this study are presented in this report.

Borenstein, Meredith S.; Golet, Francis C.; Armstrong, David S.; Breault, Robert F.; McCobb, Timothy D.; Weiskel, Peter K.

2012-01-01

140

Vegetation, Invertebrate, and Wildlife Community Rankings and Habitat Analysis of Mitigation Wetlands in West Virginia  

Microsoft Academic Search

Numerous efforts have been made in West Virginia to construct and restore compensatory wetlands as mitigation for natural wetlands destroyed through highway development, timbering, mining, and other human activities. Because such little effort has been made to evaluate these wetlands, there is a need to evaluate the success of these systems. The objective of this study was to determine if

Collin K. Balcombe; James T. Anderson; Ronald H. Fortney; Walter S. Kordek

2005-01-01

141

Responses of wetland invertebrates and plants important in waterfowl diets to burning and mowing of emergent vegetation  

Microsoft Academic Search

We examined the responses of invertebrates and plants important in waterfowl diets to two management methods (prescribed burning\\u000a and mowing) commonly used in seasonal wetlands. Experimental plots were constructed in summer 1992 in stands of saltgrass\\u000a (Distichlis spicata); 50% of the vegetation was removed in treatment areas (10 m × 10 m) by either burning or mowing. After the plots

Ferenc A. de Szalay; Vincent H. Resh

1997-01-01

142

Demonstration of wetland vegetation mapping in Florida from computer-processed satellite and aircraft multispectral scanner data  

NASA Technical Reports Server (NTRS)

The success of remotely mapping wetland vegetation of the southwestern coast of Florida is examined. A computerized technique to process aircraft and LANDSAT multispectral scanner data into vegetation classification maps was used. The cost effectiveness of this mapping technique was evaluated in terms of user requirements, accuracy, and cost. Results indicate that mangrove communities are classified most cost effectively by the LANDSAT technique, with an accuracy of approximately 87 percent and with a cost of approximately 3 cent per hectare compared to $46.50 per hectare for conventional ground survey methods.

Butera, M. K.

1979-01-01

143

Establishment, growth and survival of natural regeneration after clearcutting and drainage on forested wetlands  

Microsoft Academic Search

Natural regeneration may be disrupted by the rise of the water table in surface layers after clearcutting forested wetlands. A study was initiated on eight forested wetlands that were successively clearcut and drained 3 years later. The objectives were (1) to assess conifer and deciduous regeneration on waterlogged clearcut sites, (2) to determine the effect of water table level changes

Vincent Roy; Jean-Claude Ruel; André P Plamondon

2000-01-01

144

Vegetation types alter soil respiration and its temperature sensitivity at the field scale in an estuary wetland.  

PubMed

Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil) in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively). During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m(-2) s(-1)), followed by the Suaeda salsa site (0.77 µmol CO2 m(-2) s(-1)) and the bare soil site (0.41 µmol CO2 m(-2) s(-1)). The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland. PMID:24608636

Han, Guangxuan; Xing, Qinghui; Luo, Yiqi; Rafique, Rashad; Yu, Junbao; Mikle, Nate

2014-01-01

145

Vegetation Types Alter Soil Respiration and Its Temperature Sensitivity at the Field Scale in an Estuary Wetland  

PubMed Central

Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil) in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively). During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m?2 s?1), followed by the Suaeda salsa site (0.77 µmol CO2 m?2 s?1) and the bare soil site (0.41 µmol CO2 m?2 s?1). The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland. PMID:24608636

Han, Guangxuan; Xing, Qinghui; Luo, Yiqi; Rafique, Rashad; Yu, Junbao; Mikle, Nate

2014-01-01

146

Hydrology, vegetation, and soils of four north Florida River flood plains with an evaluation of state and federal wetland determinations  

USGS Publications Warehouse

A study of hydrologic conditions, vegetation, and soils was made in wetland forests of four north Florida streams from 1987 to 1990. The study was conducted by the U.S. Geological Survey in cooperation with the Florida Department of Environmental Regulation to support State and Federal efforts to improve wetland delineation methodology in flood plains. Plant communities and soils were described and related to topographic position and long-term hydrologic conditions at 10 study plots located on 4 streams. Detailed appendixes give average duration, frequency, and depth of flooding; canopy, subcanopy, and ground-cover vegetation; and taxonomic classification, series, and profile descriptions of soils for each plot. Topographic relief, range in stage, and depth of flooding were greatest on the alluvial flood plain of the Ochlockonee River, the largest of the four streams. Soils were silty in the lower elevations of the flood plain, and tree communities were distinctly different in each topographic zone. The Aucilla River flood plain was dominated by levees and terraces with very few depressions or low backwater areas. Oaks dominated the canopy of both lower and upper terraces of the Aucilla flood plain. Telogia Creek is a blackwater stream that is a major tributary of the Ochlockonee River. Its low, wet flood plain was dominated by Wyssa ogeche (Ogeechee tupelo) trees, had soils with mucky horizons, and was inundated by frequent floods of very short duration. The St. Marks River, a spring-fed stream with high base flow, had the least topographic relief and lowest range in stage of the four streams. St. Marks soils had a higher clay content than the other streams, and limestone bedrock was relatively close to the surface. Wetland determinations of the study plots based on State and Federal regulatory criteria were evaluated. Most State and Federal wetland determinations are based primarily on vegetation and soil characteristics because hydrologic records are usually not available. In this study, plots were located near long-term gaging stations, thus wetland determinations based on plant and soil characteristics could be evaluated at sites where long-term hydrologic conditions were known. Inconsistencies among hydrology, vegetation, and soil determinations were greatest on levee communities of the Ochlockonee and Aucilla River flood plains. Duration of average annual longest flood was almost 2 weeks for both plots. The wetland species list currently used (1991) by the State lacks many ground-cover species common to forested flood plains of north Florida rivers. There were 102 ground-cover species considered upland plants by the State that were present on the nine annually flooded plots of this study. Among them were 34 species that grew in areas continuously flooded for an average of 5 weeks or more each year. Common flood-plain species considered upland plants by the State were: Hypoxis leptocarpa (yellow star-grass), and two woody vines, Brunnichia ovata (ladies' eardrops) and Campsis radicans (trumpet-creeper), which were common in areas flooded continuously for 6 to 9 weeks a year; Sebastiania fruticosa (Sebastian-bush), Chasmanthium laxum (spikegrass), and Panicum dichotomum (panic grass), which typically grew in areas flooded an average of 2 to 3 weeks or more per year; Vitis rotundifolia (muscadine) and Toxicodendron radicans (poison-ivy), usually occurring in areas flooded an average of 1 to 2 weeks a year; and Quercus virginiana (live oak) present most often in areas flooded approximately 1 week a year. Federal wetland regulations (1989) limited wetland jurisdiction to only those areas that are inundated or saturated during the growing season. However, year-round hydrologic records were chosen in this report to describe the influence of hydrology on vegetation, because saturation, inundation, or flowing water can have a variety of both beneficial and adverse effects on flood-plain vegetation at any time of the

Light, H.M.; Darst, M.R.; MacLaughlin, M.T.; Sprecher, S.W.

1993-01-01

147

Isolated Spring Wetlands in the Great Basin and Mojave Deserts, USA: Potential Response of Vegetation to Groundwater Withdrawal  

NASA Astrophysics Data System (ADS)

Desert springs, often the sole sources of water for wildlife and cattle, support wetland and wetland/upland transition ecosystems including rare and endemic species. In the basin and range province in Nevada, USA, springs in the Great Basin and Mojave deserts are sustained by interconnected deep carbonate and shallow basin-fill aquifers which are threatened by proposed groundwater withdrawal to sustain rapidly expanding urban areas, a common problem in arid regions worldwide. This paper draws on historic groundwater data, groundwater modeling, and studies of environmental controls of spring ecosystems to speculate on the potential effects of groundwater withdrawal and water table decline on spring-supported vegetation. The focus is on springs in the Great Basin and Mojave deserts representative of those that may be affected by future, planned groundwater withdrawal. Groundwater withdrawal is expected to reduce spring discharge directly through reduced flows from the shallow basin-fill aquifer or through reduction of the hydraulic head of the deep carbonate aquifer. This flow reduction will truncate the outflow stream, reducing the areal cover of wetland and wetland/upland transition vegetation. Lowering the local water table may also reduce the amount of upland phreatophytic vegetation by causing water levels to drop below plant rooting depths. Percolation of salts to surface soils may be reduced, eventually altering desert shrub cover from halophytes to nonhalophytes. The extent of these effects will vary among springs, based on their distance from extraction sites and location relative to regional groundwater flow paths. On-site monitoring of biotic variables (including cover of selected hygrophytes and phreatophytes) should be a necessary complement to the planned monitoring of local hydrologic conditions.

Patten, Duncan T.; Rouse, Leigh; Stromberg, Juliet C.

2008-03-01

148

Vegetation establishment on a deposit of zinc mine wastes.  

PubMed

Field trials concerning the establishment of plant cover on a deposit of wastes from the Ammeberg zinc mine in central Sweden were carried out during 1976-1985. Different soil conditioners and manures were applied and plant species cultivars were evaluated with regard to plant biomass, vigour, durability and content of zinc, lead and cadmium. Sewage sludge and topsoil led to better establishment of grasses than did municipal waste, straw and hydraulic seeding. After 2 years, Festuca rubra and Poa pratensis dominated the swards. Other species (Dactylis glomerata, Bromus inermis, Lolium perenne, Phleum nodosum, Festuca pratensis and F. arundinacea) constituted only a minor part of the stand. After 10 years, F. rubra was the most dominant species, while native Agrostis tenuis had invaded 20-50% of the area within the plots. Merlin was the clearly dominant red fescue cultivar. The concentration of zinc in shoots (616 mg kg(-1) dw) was about 10% of that in the soil. Zinc concentration decreased with increasing biomass above ground. It increased with age in Scots pine needles and was very high in birch leaves. Grasses survived longer than legumes in the zinc sand waste. Among the surviving grasses was a group with high (3800 mg kg(-1) dw) and a group with low (320 mg kg(-1) dw) zinc concentrations. The low group included Merlin red fescue and Sobel creeping bent. The cultivar Merlin contained a much lower zinc concentration than the other cultivars of red fescue (375 and 624 mg kg(-1) dw, respectively). A large amount of root biomass was present in plots with dominating Merlin red fescue (1715 g m(-2)), 97% of which was concentrated in the top 10 cm of the soil. The concentration of zinc in the roots was very high (13 000-25 000 mg kg(-1) dw). Nitrate fertilizer, especially ammonium nitrate, and acidic water (pH 4.3) increased zinc leaching. PMID:15092483

Bergholm, J; Steen, E

1989-01-01

149

CHARACTERIZATION OF MICROTOPOGRAPHY AND ITS INFLUENCE ON VEGETATION PATTERNS IN CREATED WETLANDS  

E-print Network

. Elevation, steel rod oxidation depth, and species cover were measured along replicate multiscale (0.5 m-, 1, limiting slope, and limiting elevation difference. Steel rod oxidation depth was used to estimate water wetlands created to mitigate wetland losses fail to meet basic success criteria within the time frame

150

Effects of Woody Vegetation on Prairie Wetland Birds DAVID E. NAUGLE1  

E-print Network

. this region has been transformed from a contiguous expanse of wetlands and grasslands into a highly fragmented of associ- ated uplands. and the cessation of large-scale natural disturbances such as fire and grazing. Suppression of natural disturbances that historical- ly deterred woody-species growth around wetlands has

151

Independent Wetland Vegetation Response to Climate Variability and Anthropogenic Hydrologic Control, Everglades, FL, USA  

NASA Astrophysics Data System (ADS)

The response of a wetland landscape composed of multiple, distinct, plant communities to a single stimulus, whether it results from natural climate variability or human alterations, should not be assumed to be uniform across the entire landscape. The Florida Everglades is such a landscape where elevated sawgrass ridges are immediately next to water lily dominated sloughs, known collectively as the sawgrass ridge and slough landscape (SRS). The distribution of the Everglades individual sawgrass ridge and slough plant communities within the SRS was altered by 20th century construction of water control structures (canals, levees, and dikes) and alteration of the natural hydrologic regime. Although restoration planning to stabilize the remaining ridge and slough habitats is underway, little is known about the landscape's origin and response to past hydrologic changes. Analysis of pollen assemblages from transects of piston cores collected across SRS indicate that sawgrass ridges and sloughs have been vegetationally distinct from one another since the mid Holocene. Modern sawgrass ridges formed from a marsh-like environment, whereas slough communities occupied their present sites throughout the history of the sites. Ridge formation was triggered by intervals of drier climate (i.e., the Medieval Warm Period and Little Ice Age) and changes in the mean position of the Intertropical Convergence Zone. The sloughs are temporarily composed of more marsh plants during drier conditions, but quickly return to their original state when precipitation increases. During the 20th century, sloughs appear to be strongly influenced by North Atlantic Oscillation (NAO) variability in spite of water management practices, while the sawgrass ridges respond primarily to [water management] anthropogenic changes in hydrology. Our evidence that, the sawgrass ridge and slough landscape communities can act independent of one another to changes in hydrology, indicates that restoring the pre-20th century hydrology may not restore all aspects of the pre-20th century landscape structure.

Bernhardt, C. E.; Willard, D. A.

2007-12-01

152

Physical and Vegetative Characteristics of a Newly Constructed Wetland and Modified Stream Reach, Tredyffrin Township, Chester County, Pennsylvania, 2000-2006  

USGS Publications Warehouse

To compensate for authorized disturbance of naturally occurring wetlands and streams during roadway improvements to U.S. Highway 202 in Chester and Montgomery Counties, Pa., the Pennsylvania Department of Transportation (PennDOT) constructed 0.42 acre of emergent wetland and 0.94 acre of scrub-shrub/forested wetland and modified sections of a 1,600-foot reach of Valley Creek with woody riparian plantings and streambank-stabilization structures (including rock deflectors). In accordance with project permits and additional guidance issued by the U.S. Army Corps of Engineers, the U.S. Geological Survey (USGS), in cooperation with PennDOT, collected data from 2000 through 2006 to quantify changes in 1) the vegetation, soils, and extent of emergent and scrub-shrub/forested parts of the constructed wetland, 2) the profile, dimension, and substrate in the vicinity of rock deflectors placed at two locations within the modified stream reach, and 3) the woody vegetation within the planted riparian buffer. The data for this investigation were collected using an approach adapted from previous investigations so that technology and findings may be more easily transferred among projects with similar objectives. Areal cover by planted and non-planted vegetation growing within the emergent and scrub-shrub/forested parts of the constructed wetland exceeded 85 percent at the end of each growing season, a criterion in special condition 25c in the U.S. Army Corps of Engineers project permit. Areal cover of vegetation in emergent and scrub-shrub/forested parts of the constructed wetland exceeded 100 percent in all but one growing season. Frequent and long-lasting soil saturation favored obligate-wetland species like Typha latifolia (broadleaf cattail) and Scirpus validus (great bulrush), both of which maintained dominance in the emergent wetland throughout the study (percent cover was 20 and 78 percent, respectively, in 2006). Echinocloa crusgalli (barnyard grass), an annual invasive from Eurasia, initially established in the newly disturbed soils of the scrub-shrub/forested wetland (areal cover was 56 percent in 2000), but by 2002, E. crusgalli was not growing in any sample plots and other species including Agrostis stolonifera (creeping bent grass), Festuca rubra (red fescue), Cornus spp. (dogwood species), and Salix nigra (black willow) were becoming more common. Sal. nigra contributed 30-percent cover in the scrub-shrub/forested wetland part by fall 2003. Rapid colonization of this species in subsequent years increased annual cover through 2006, when 15- to 25-foot tall Sal. nigra trees dominated the tree/shrub stratum (48 percent of the areal cover in 2006). The understory of the scrub-shrub/forested wetland was mostly shaded because of the canopy of Sal. nigra trees. Herbaceous species growing under and near the margins of the canopy included Ag. stolonifera and Ty. latifolia (29- and 23-percent areal cover, respectively). Flows in Valley Creek are responsible for transporting sediment and shaping the channel. Annual mean streamflow during the period the modified stream reach was monitored ranged from 15.2 cubic feet per second (ft3/s) in the 2002 water year to 53.0 ft3/s in the 2004 water year. This is a range of about 55 percent lower to 58 percent higher than the annual mean streamflow for the period of record. Despite the variability in streamflow, longitudinal profiles surveyed near rock deflectors in two short (100-foot) reaches within the modified stream reach maintained a constant slope throughout the monitoring period, most likely because of the presence of bedrock control. Cross-section geometry in the upstream reach was virtually unchanged during the monitoring period but 10 feet of bank migration was measured downstream, leaving the rock deflectors in mid-stream. As indicated by the change in channel morphology at the downstream reach, it is apparent that the rock deflectors were ineffective at adequately protecting the bank

Chaplin, Jeffrey J.; White, Kirk E.; Olson, Leif E.

2009-01-01

153

Coastal vegetation planting projects for tsunami disaster mitigation: effectiveness evaluation of new establishments  

Microsoft Academic Search

Coastal vegetation acts as a natural barrier against extreme natural and anthropogenic activities, protecting infrastructure\\u000a and human lives. Establishment of hard infrastructure for tsunami protection is not feasible in developing countries due to\\u000a its cost-intensive nature. Coastal vegetation can therefore be a feasible alternative for tsunami and general coastal protection\\u000a in developing countries. This study investigates the effectiveness of current

Norio Tanaka; K. B. S. N. Jinadasa; M. I. M. Mowjood; M. S. M. Fasly

2011-01-01

154

Physical and vegetative characteristics of a relocated stream reach, constructed wetland, and riparian buffer, Upper Saucon Township, Lehigh County, Pennsylvania, 2000-04  

USGS Publications Warehouse

The U.S. Geological Survey, in cooperation with the Pennsylvania Department of Transportation, Engineering District 5-0, investigated physical and vegetative changes within a relocated stream reach, constructed wetland, and riparian buffer from September 2000 to October 2004. This report presents an evaluation of data collected using methods from multiple sources that have been adapted into a consistent approach. This approach is intended to satisfy a need for consistent collection of different types of data with the goal of transferring technology and findings to similar projects. Survey data indicate that adjustment of the upstream part of the relocated stream reach slowed over the monitoring period, but the downstream channel remains unstable as evidenced by excessive deposition. Upstream migration of a nick point has slowed or stopped altogether as of the 2003 assessment when this feature came in contact with the upstream-most part of the channel that is lined with riprap. Documented streambed erosion in the upstream cross sections, along with deposition downstream, has resulted in an overall decrease in slope of the stream channel over the monitoring period. Most streambed erosion took place prior to the 2002 assessment when annual mean streamflows were less than those in the final 2 years of monitoring. An abundance of fine sediment dominates the substrate of the relocated channel. Annual fluctuations of large particles within each cross section demonstrates the capacity of the relocated channel to transport the entire range of sediment. The substrate within the 0.28-acre constructed wetland (a mixture of soil from an off-site naturally occurring wetland and woodchips) supported a hydrophytic-vegetation community throughout the investigation. Eleocharis obtusa (spike rush), an obligate-wetland herb, was the most prevalent species, having a maximum areal cover of 90 percent in fall 2001 and a minimum of 23 percent in fall 2004. Drought-like conditions in water year 2002 (cumulative precipitation was 28.11 inches) allowed species like Panicum dichotomiflorum (witch grass), Salix sp. (willow), Leersia oryzoides (rice cutgrass), and Echinocloa crusgalli (barnyard grass) to become established by fall 2002. Above-average precipitation in water years 2003 and 2004 (58.55 and 53.17 inches, respectively) coincided with increased areal cover by E. obtusa in fall 2003 (56 percent) and decreased areal cover in fall 2004 (23 percent). Pond-like conditions that probably persisted throughout the 2004 growing season favored aquatic species like Alisma subcordatum (water plantain) to the detriment of many emergent species, including E. obtusa. Despite the pond-like conditions, L. oryzoides, an obligate-wetland grass, increased in areal cover (from 12 to 34 percent) between the 2003 and 2004 growing seasons because it was established in the higher elevations and the peripheral areas of the constructed wetland that were less prone to persistent inundation. Canopy development by trees and shrubs in the riparian buffer was initially (fall 2000) poor (39.7 percent), resulting in more available sunlight for the herbaceous understory than in any other growing season. As a result, areal cover of herbaceous species and trees and shrubs less than 1-meter tall was 108 percent in fall 2000 with Lolium perenne (perennial rye), Polygonum persicaria (lady's thumb), and Setaria faberi (foxtail) collectively contributing nearly half the cover (59.2 percent). Because of increases in canopy cover by trees and shrubs (39.7 percent in fall 2000 to 127 percent in fall 2004), herbaceous cover decreased to 76 percent by the fall of 2001 and varied between 72 and 77 percent for the rest of the study period. Tree density in the riparian buffer ranged from 3,078 and 4,130 plants per acre (fall 2000 and 2003, respectively) over the study period but essentially remained constant after fall 2001; computations reported each fall between fall 2001 and fall

Chaplin, Jeffrey J.; White, Kirk E.; Loper, Connie A.

2006-01-01

155

Mercury cycling in agricultural and managed wetlands of California: seasonal influences of vegetation on mercury methylation, storage, and transport  

USGS Publications Warehouse

Plants are a dominant biologic and physical component of many wetland capable of influencing the internal pools and fluxes of methylmercury (MeHg). To investigate their role with respect to the latter, we examined the changing seasonal roles of vegetation biomass and Hg, C and N composition from May 2007-February 2008 in 3 types of agricultural wetlands (domesticated or white rice, wild rice, and fallow fields), and in adjacent managed natural wetlands dominated by cattail and bulrush (tule). We also determined the impact of vegetation on seasonal microbial Hg methylation rates, and Hg and MeHg export via seasonal storage in vegetation, and biotic consumption of rice seed. Despite a compressed growing season of ~ 3 months, annual net primary productivity (NPP) was greatest in white rice fields and carbon more labile (leaf median C:N ratio = 27). Decay of senescent litter (residue) was correlated with microbial MeHg production in winter among all wetlands. As agricultural biomass accumulated from July to August, THg concentrations declined in leaves but MeHg concentrations remained consistent, such that MeHg pools generally increased with growth. Vegetation provided a small, temporary, but significant storage term for MeHg in agricultural fields when compared with hydrologic export. White rice and wild rice seeds reached mean MeHg concentrations of 4.1 and 6.2 ng gdw- 1, respectively. In white rice and wild rice fields, seed MeHg concentrations were correlated with root MeHg concentrations (r = 0.90, p < 0.001), suggesting transport of MeHg to seeds from belowground tissues. Given the proportionally elevated concentrations of MeHg in rice seeds, white and wild rice crops may act as a conduit of MeHg into biota, especially waterfowl which forage heavily on rice seeds within the Central Valley of California, USA. Thus, while plant tissues and rhizosphere soils provide temporary storage for MeHg during the growing season, export of MeHg is enhanced post-harvest through increased hydrologic and biotic export.

Windham-Myers, Lisamarie; Marvin-DiPasquale, Mark C.; Kakouros, Evangelos; Agee, Jennifer L.; Kieu, Le H.; Stricker, Craig A.; Fleck, Jacob A.; Ackerman, Joshua T.

2013-01-01

156

Control of reed canarygrass promotes wetland herb and tree seedling establishment in an upper Mississippi River Floodplain forest  

USGS Publications Warehouse

Phalaris arundinacea (reed canarygrass) is recognized as a problematic invader of North American marshes, decreasing biodiversity and persisting in the face of control efforts. Less is known about its ecology or management in forested wetlands, providing an opportunity to apply information about factors critical to an invader's control in one wetland type to another. In a potted plant experiment and in the field, we documented strong competitive effects of reed canarygrass on the establishment and early growth of tree seedlings. In the field, we demonstrated the effectiveness of a novel restoration strategy, combining site scarification with late fall applications of pre-emergent herbicides. Treatments delayed reed canarygrass emergence the following spring, creating a window of opportunity for the early growth of native plants in the absence of competition from the grass. They also allowed for follow-up herbicide treatments during the growing season. We documented greater establishment of wetland herbs and tree seedlings in treated areas. Data from small exclosures suggest, however, that deer browsing can limit tree seedling height growth in floodplain restorations. Slower tree growth will delay canopy closure, potentially allowing reed canarygrass re-invasion. Thus, it may be necessary to protect tree seedlings from herbivory to assure forest regeneration.

Thomsen, Meredith; Brownell, Kurt; Groshek, Matthew; Kirsch, Eileen

2012-01-01

157

Catastrophic Shifts in Wetland Geomorphology and Ecology in Response to Hydrology-Vegetation-Sediment Transport Feedbacks (Invited)  

NASA Astrophysics Data System (ADS)

Coastal marshes and long-hydroperiod floodplain wetlands exhibit strong bi-directional feedback between hydrology, vegetation, and sediment that impacts landscape dynamics and ecosystem services. In these ecosystems, vegetation responds to and also influences the distribution of topography, with effects on habitat provision, biological diversity, landscape connectivity, surface-subsurface exchange, and microbial and redox reactions. Topography evolves both autogenically and allogenically. Autogenically, peat accretes under reducing conditions as a function of local water levels, vegetation community, and nutrient concentrations. Concurrently, an allogenic sediment redistribution feedback process involves erosion of sediment from low, sparsely vegetated areas and deposition of sediment within dense vegetation that resists flow. It is well documented that these feedback processes are dominantly responsible for evolution of tidal marsh morphology and response of coastal marshes to sea level rise. Less well understood is the role these feedbacks play in the evolution of more slowly flowing interior marshes and in the response of these systems to perturbations in flow velocity as well as water level. We developed a cellular automata model that physically simulates both sediment redistribution and differential peat accretion feedbacks. Because of the efficiency of this simplified modeling technique, we ran the model over a broad range of environmental conditions in a generalized sensitivity analysis. As a result of the two feedback processes, simulated landscapes reflected a variety of morphologies found in coastal and interior wetlands worldwide, with differences attributable to relative dominance of physical (e.g., surface-water flow, water level) or biological (e.g., vegetation productivity and colonization) drivers. Significantly, under moderate surface-water flow velocities (4-6 cm s-1), a class of patterned wetlands with regular ridges and sloughs oriented parallel to the dominant flow direction emerged, which mimics the patterned, flow-parallel topography found in the Florida Everglades. Sediment redistribution and differential peat accretion feedbacks constitute the first description of a viable mechanism for formation of this ecologically important landscape structure and provide guidance for restoration efforts. We show that because of vegetative resistance to flow, this patterned landscape structure is prone to shift to an alternate stable state, dominated by a monoculture of emergent vegetation, under changes in surface-water flow velocity or water level. Results suggest that twentieth-century degradation of the Everglades ridge and slough landscape is attributable primarily to changes in water level and, secondarily, to diminished surface-water flow velocities. Because hydrology-vegetation-sediment feedbacks cause hysteresis in landscape evolution trajectories, restoration of historic flow velocities and water levels will not necessarily produce a return to historic landscape structure. Understanding the dynamics of sediment redistribution and differential peat accretion feedbacks will be essential in predicting how wetlands worldwide will respond to changes in climate or water management.

Larsen, L. G.; Harvey, J. W.

2010-12-01

158

Experimental removal of wetland emergent vegetation leads to decreased methylmercury production in surface sediment  

Microsoft Academic Search

We performed plant removal (devegetation) experiments across a suite of ecologically diverse wetland settings (tidal salt marshes, river floodplain, rotational rice fields, and freshwater wetlands with permanent or seasonal flooding) to determine the extent to which the presence (or absence) of actively growing plants influences the activity of the Hg(II)-methylating microbial community and the availability of Hg(II) to those microbes.

Lisamarie Windham-Myers; Mark Marvin-Dipasquale; David P. Krabbenhoft; Jennifer L. Agee; Marisa H. Cox; Pilar Heredia-Middleton; Carolyn Coates; Evangelos Kakouros

2009-01-01

159

Restoration of aquatic macrophyte vegetation in acidified and eutrophicated shallow soft water wetlands in the Netherlands  

Microsoft Academic Search

Soft water lakes possess a highly characteristic vegetation adapted to limitation of carbon. Based upon hydrology, vegetation and geographic distribution, boreal and Atlantic lake types can be distinguished. Reducing the input of nutrients or liming, or both, the stream or its catchment is generally sufficient to restore typical soft water vegetation of boreal soft water lakes. The vegetation of Atlantic

J. G. M. Roelofs; E. Brouwer; R. Bobbink

2002-01-01

160

Landscape object-based analysis of wetland plant functional types: the effects of spatial scale, vegetation classes and classifier methods  

NASA Astrophysics Data System (ADS)

Remote sensing-based vegetation classifications representing plant function such as photosynthesis and productivity are challenging in wetlands with complex cover and difficult field access. Recent advances in object-based image analysis (OBIA) and machine-learning algorithms offer new classification tools; however, few comparisons of different algorithms and spatial scales have been discussed to date. We applied OBIA to delineate wetland plant functional types (PFTs) for Poyang Lake, the largest freshwater lake in China and Ramsar wetland conservation site, from 30-m Landsat TM scene at the peak of spring growing season. We targeted major PFTs (C3 grasses, C3 forbs and different types of C4 grasses and aquatic vegetation) that are both key players in system's biogeochemical cycles and critical providers of waterbird habitat. Classification results were compared among: a) several object segmentation scales (with average object sizes 900-9000 m2); b) several families of statistical classifiers (including Bayesian, Logistic, Neural Network, Decision Trees and Support Vector Machines) and c) two hierarchical levels of vegetation classification, a generalized 3-class set and more detailed 6-class set. We found that classification benefited from object-based approach which allowed including object shape, texture and context descriptors in classification. While a number of classifiers achieved high accuracy at the finest pixel-equivalent segmentation scale, the highest accuracies and best agreement among algorithms occurred at coarser object scales. No single classifier was consistently superior across all scales, although selected algorithms of Neural Network, Logistic and K-Nearest Neighbors families frequently provided the best discrimination of classes at different scales. The choice of vegetation categories also affected classification accuracy. The 6-class set allowed for higher individual class accuracies but lower overall accuracies than the 3-class set because individual classes differed in scales at which they were best discriminated from others. Main classification challenges included a) presence of C3 grasses in C4-grass areas, particularly following harvesting of C4 reeds and b) mixtures of emergent, floating and submerged aquatic plants at sub-object and sub-pixel scales. We conclude that OBIA with advanced statistical classifiers offers useful instruments for landscape vegetation analyses, and that spatial scale considerations are critical in mapping PFTs, while multi-scale comparisons can be used to guide class selection. Future work will further apply fuzzy classification and field-collected spectral data for PFT analysis and compare results with MODIS PFT products.

Dronova, I.; Gong, P.; Wang, L.; Clinton, N.; Fu, W.; Qi, S.

2011-12-01

161

Gas exchange in wetlands with emergent vegetation: The effects of wind and thermal convection at the air-water interface  

NASA Astrophysics Data System (ADS)

Methane, carbon dioxide, and oxygen are exchanged between wetlands and the atmosphere through multiple pathways. One of these pathways, the hydrodynamic transport of dissolved gas through the surface water, is often underestimated in importance. We constructed a model wetland in the laboratory with artificial emergent plants to investigate the mechanisms and magnitude of this transport. We measured gas transfer velocities, which characterize the near-surface stirring driving air-water gas transfer, while varying two stirring processes important to gas exchange in other aquatic environments: wind and thermal convection. To isolate the effects of thermal convection, we identified a semiempirical model for the gas transfer velocity as a function of surface heat loss. The laboratory results indicate that thermal convection will be the dominant mechanism of air-water gas exchange in marshes with emergent vegetation. Thermal convection yielded peak gas transfer velocities of 1 cm h-1. Because of the sheltering of the water surface by emergent vegetation, gas transfer velocities for wind-driven stirring alone are likely to exceed this value only in extreme cases.

Poindexter, Cristina M.; Variano, Evan A.

2013-07-01

162

FLUE GAS DESULFURIZATION SLUDGE: ESTABLISHMENT OF VEGETATION ON PONDED AND SOIL-APPLIED WASTE  

EPA Science Inventory

The report gives results of research to identify and evaluate forms of vegetation and methods of their establishment for reclaiming retired flue gas desulfurization sludge ponds. Also studied were the soil liming value of limestone scrubber sludge (LSS) and plant uptake and perco...

163

Camera derived vegetation greenness index as proxy for gross primary production in a low Arctic wetland area  

NASA Astrophysics Data System (ADS)

The Arctic is experiencing disproportionate warming relative to the global average, and the Arctic ecosystems are as a result undergoing considerable changes. Continued monitoring of ecosystem productivity and phenology across temporal and spatial scales is a central part of assessing the magnitude of these changes. This study investigates the ability to use automatic digital camera images (DCIs) as proxy data for gross primary production (GPP) in a complex low Arctic wetland site. Vegetation greenness computed from DCIs was found to correlate significantly (R2 = 0.62, p < 0.001) with a normalized difference vegetation index (NDVI) product derived from the WorldView-2 satellite. An object-based classification based on a bi-temporal image composite was used to classify the study area into heath, copse, fen, and bedrock. Temporal evolution of vegetation greenness was evaluated and modeled with double sigmoid functions for each plant community. GPP at light saturation modeled from eddy covariance (EC) flux measurements were found to correlate significantly with vegetation greenness for all plant communities in the studied year (i.e., 2010), and the highest correlation was found between modeled fen greenness and GPP (R2 = 0.85, p < 0.001). Finally, greenness computed within modeled EC footprints were used to evaluate the influence of individual plant communities on the flux measurements. The study concludes that digital cameras may be used as a cost-effective proxy for potential GPP in remote Arctic regions.

Westergaard-Nielsen, Andreas; Lund, Magnus; Hansen, Birger Ulf; Tamstorf, Mikkel Peter

2013-12-01

164

Mercury cycling in agricultural and managed wetlands of California: experimental evidence of vegetation-driven changes in sediment biogeochemistry and methylmercury production  

USGS Publications Warehouse

The role of live vegetation in sediment methylmercury (MeHg) production and associated biogeochemistry was examined in three types of agricultural wetlands (domesticated or white rice, wild rice, and fallow fields) and adjacent managed natural wetlands (cattail- and bulrush or tule-dominated) in the Yolo Bypass region of California's Central Valley, USA. During the active growing season for each wetland, a vegetated:de-vegetated paired plot experiment demonstrated that the presence of live plants enhanced microbial rates of mercury methylation by 20 to 669% (median = 280%) compared to de-vegetated plots. Labile carbon exudation by roots appeared to be the primary mechanism by which microbial methylation was enhanced in the presence of vegetation. Pore-water acetate (pw[Ac]) decreased significantly with de-vegetation (63 to 99%) among all wetland types, and within cropped fields, pw[Ac] was correlated with both root density (r = 0.92) and microbial Hg(II) methylation (kmeth. r = 0.65). Sediment biogeochemical responses to de-vegetation were inconsistent between treatments for “reactive Hg” (Hg(II)R), as were reduced sulfur and sulfate reduction rates. Sediment MeHg concentrations in vegetated plots were double those of de-vegetated plots (median = 205%), due in part to enhanced microbial MeHg production in the rhizosphere, and in part to rhizoconcentration via transpiration-driven pore-water transport. Pore-water concentrations of chloride, a conservative tracer, were elevated (median = 22%) in vegetated plots, suggesting that the higher concentrations of other constituents around roots may also be a function of rhizoconcentration rather than microbial activity alone. Elevated pools of amorphous iron (Fe) in vegetated plots indicate that downward redistribution of oxic surface waters through transpiration acts as a stimulant to Fe(III)-reduction through oxidation of Fe(II)pools. These data suggest that vegetation significantly affected rhizosphere biogeochemistry through organic exudation and transpiration-driven concentration of pore-water constituents and oxidation of reduced compounds. While the relative role of vegetation varied among wetland types, macrophyte activity enhanced MeHg production.

Windham-Myers, Lisamarie; Marvin-DiPasquale, Mark; Stricker, Craig A.; Agee, Jennifer L.; Kieu, Le H.; Kakouros, Evangelos

2014-01-01

165

Mercury cycling in agricultural and managed wetlands of California, USA: experimental evidence of vegetation-driven changes in sediment biogeochemistry and methylmercury production.  

PubMed

The role of live vegetation in sediment methylmercury (MeHg) production and associated biogeochemistry was examined in three types of agricultural wetlands (domesticated or white rice, wild rice, and fallow fields) and adjacent managed natural wetlands (cattail- and bulrush or tule-dominated) in the Yolo Bypass region of California's Central Valley, USA. During the active growing season for each wetland, a vegetated:de-vegetated paired plot experiment demonstrated that the presence of live plants enhanced microbial rates of mercury methylation by 20 to 669% (median=280%) compared to de-vegetated plots. Labile carbon exudation by roots appeared to be the primary mechanism by which microbial methylation was enhanced in the presence of vegetation. Pore-water acetate (pw[Ac]) decreased significantly with de-vegetation (63 to 99%) among all wetland types, and within cropped fields, pw[Ac] was correlated with both root density (r=0.92) and microbial Hg(II) methylation (kmeth. r=0.65). Sediment biogeochemical responses to de-vegetation were inconsistent between treatments for "reactive Hg" (Hg(II)R), as were reduced sulfur and sulfate reduction rates. Sediment MeHg concentrations in vegetated plots were double those of de-vegetated plots (median=205%), due in part to enhanced microbial MeHg production in the rhizosphere, and in part to rhizoconcentration via transpiration-driven pore-water transport. Pore-water concentrations of chloride, a conservative tracer, were elevated (median=22%) in vegetated plots, suggesting that the higher concentrations of other constituents around roots may also be a function of rhizoconcentration rather than microbial activity alone. Elevated pools of amorphous iron (Fe) in vegetated plots indicate that downward redistribution of oxic surface waters through transpiration acts as a stimulant to Fe(III)-reduction through oxidation of Fe(II)pools. These data suggest that vegetation significantly affected rhizosphere biogeochemistry through organic exudation and transpiration-driven concentration of pore-water constituents and oxidation of reduced compounds. While the relative role of vegetation varied among wetland types, macrophyte activity enhanced MeHg production. PMID:23809881

Windham-Myers, Lisamarie; Marvin-DiPasquale, Mark; A Stricker, Craig; Agee, Jennifer L; H Kieu, Le; Kakouros, Evangelos

2014-06-15

166

Evaluating the effect of rainfall variability on vegetation establishment in a semidesert grassland.  

PubMed

Of the operations required for reclamation in arid and semi-arid regions, establishing vegetation entails the most uncertainty due to reliance on unpredictable rainfall for seed germination and seedling establishment. The frequency of successful vegetation establishment was estimated based on a land surface model driven by hourly atmospheric forcing data, 7 years of eddy-flux data, and 31 years of rainfall data at two adjacent sites in southern Arizona, USA. Two scenarios differing in the required imbibition time for successful germination were evaluated-2 or 3 days availability of sufficient surface moisture. Establishment success was assumed to occur if plants could germinate and if the drying front in the soil did not overtake the growth of seminal roots. Based on our results, vegetation establishment could be expected to fail in 32 % of years. In the worst 10-year span, six of ten plantings would have failed. In the best 10-year span, only one of ten was projected to fail. Across all assessments, at most 3 years in a row failed and 6 years in a row were successful. Funding for reclamation seeding must be available to allow reseeding the following year if sufficient amount and timing of rainfall does not occur. PMID:23974536

Fehmi, Jeffrey S; Niu, Guo-Yue; Scott, Russell L; Mathias, Andrea

2014-01-01

167

Vegetation effects on fecal bacteria, BOD, and suspended solid removal in constructed wetlands treating domestic wastewater  

Microsoft Academic Search

Constructed wetlands have emerged as a viable alternative for secondary treatment of domestic wastewater in areas with landscape limitations, poor soil conditions, and high water tables, which limit installation of full-scale adsorption fields. Existing information on the effects of macrophytes on treatment performance is contradictory and mostly derived from greenhouse mesocosm experiments. This study investigated the removal efficiency of fecal

A. D. Karathanasis; C. L. Potter; M. S. Coyne

2003-01-01

168

Effects of Agricultural Runoff on Vegetation Composition of a Priority Conservation Wetland, Vermont, USA  

E-print Network

's distinctive native flora is being replaced The open mat of Sphagnum covers approximately 40 hect- by widespread, vigorous species enhanced by agricultural nonpoint ares and is located in the central portion of the basin. In pollution in the watershed of Franklin Bog. Protection of wetlands addition to Sphagnum, many

Vermont, University of

169

I. Abstract Vegetation plays an important role in the surface energy and water balance of wetlands.  

E-print Network

as Phragmites australis) have been removed from portions of the riparian corridor in an effort to halt. australis land cover. Water and Energy Balance Response in Response to the Removal of Invasive Phragmites of a P. australis-dominated riparian wetland in south-central Nebraska to assess the potential

Nebraska-Lincoln, University of

170

Development and testing of an index of biotic integrity based on submersed and floating vegetation and its application to assess reclamation wetlands in Alberta's oil sands area, Canada.  

PubMed

We developed and tested a plant-based index of biological integrity (IBI) and used it to evaluate the existing reclamation wetlands in Alberta's oil sands mining region. Reclamation plans call for >15,000 ha of wetlands to be constructed, but currently, only about 25 wetlands are of suitable age for evaluation. Reclamation wetlands are typically of the shallow open water type and range from fresh to sub-saline. Tailings-contaminated wetlands in particular may have problems with hydrocarbon- and salt-related toxicity. From 60 initial candidate metrics in the submersed aquatic and floating vegetation communities, we selected five to quantify biological integrity. The IBI included two diversity-based metrics: the species richness of floating vegetation and the percent of total richness contributed by Potamogeton spp. It also included three relative abundance-based metrics: that of Ceratophyllum demersum, of floating leafed species and of alkali-tolerant species. We evaluated the contribution of nonlinear metrics to IBI performance but concluded that the correlation between IBI scores and wetland condition was not improved. The method used to score metrics had an influence on the IBI sensitivity. We conclude that continuous scoring relative to the distribution of values found in reference sites was superior. This scoring approach provided good sensitivity and resolution and was grounded in reference condition theory. Based on these IBI scores, both tailings-contaminated and tailings-free reclamation wetlands have significantly lower average biological integrity than reference wetlands (ANOVA: F(2,59) = 34.7, p = 0.000000000107). PMID:21484300

Rooney, Rebecca C; Bayley, Suzanne E

2012-01-01

171

Indicators of nitrate in wetland surface and soil-waters: interactions of vegetation and environmental factors Hydrology and Earth System Sciences, 8(4), 663672 (2004) EGU  

E-print Network

Indicators of nitrate in wetland surface and soil-waters: interactions of vegetation and environmental factors 663 Hydrology and Earth System Sciences, 8(4), 663672 (2004) © EGU Indicators of nitrate, and hence the sampling period, was MayAugust during both years. Seasonal mean concentrations of nitrate (NO3

Paris-Sud XI, Université de

172

Multisite comparison of drivers of methane emissions from wetlands in the European Arctic: influence of vegetation community and water table.  

NASA Astrophysics Data System (ADS)

Arctic and sub arctic wetlands are a major source of atmospheric CH4 and therefore have the potential to be important in controlling global radiative forcing. Furthermore, the strong links between wetland CH4 emissions and vegetation community, hydrology and temperature suggest potentially large feedbacks between climate change and future emissions. Quantifying current emissions over large spatial scales and predicting future climatic feedbacks requires a fundamental understanding of the ground based drivers of plot scale emissions. The MAMM project (Methane in the Arctic: Measurements and Modelling) aims to understand and quantify current CH4 emissions and future climatic impacts by combining both ground and aircraft measurements across the European Arctic with regional computer modelling. Here we present results from the ground-based MAMM measurement campaigns, analysing chamber-measured CH4 emissions from two sites in the European Arctic/Sub-Arctic region (Sodankylä, Finland; Stordalen Mire, Sweden) from growing seasons in 2012 and 2013. A total of 85 wetland static chambers were deployed across the two field sites; 39 at Sodankylä (67° 22'01' N, 26° 3'06' E) in 2012 and 46 at Stordalen Mire (68° 21'20' N, 19° 02'56' E) in 2013. Chamber design, protocol and deployment were the same across both sites. Chambers were located at sites chosen strategically to cover the local range of water table depths and vegetation communities. A total of 18 and 15 repeated measurements were made at each chamber in Sodankylä and Stordalen Mire, respectively, over the snow-free season. Preliminary results show a large range of CH4 fluxes across both sites ranging from a CH4 uptake of up to 0.07 and 0.06 mg CH4-C m-2 hr-1 to emissions of 17.3 and 44.2 mg CH4-C m-2 hr-1 in Sodankylä and Stordalen Mire, respectively. Empirical models based on vegetation community, water table depth, temperature and soil nutrient availability (Plant Root Simulator Probes, PRSTM) have been constructed with the aim of understanding the drivers of chamber scale fluxes. By combining measurements made at two different sites, >300km apart, using the same experimental setup, we are uniquely able to investigate whether CH4 emissions are driven by common parameters. Furthermore we are able to determine if plot scale empirical models and parameterisations can be used effectively to upscale emissions to landscape and whole Arctic scale.

Dinsmore, Kerry; Drewer, Julia; Leeson, Sarah; Skiba, Ute; Levy, Pete; George, Charles

2014-05-01

173

Establishment of submergent vegetation and invertebrates in a wetland constructed on mine soil  

E-print Network

-sloped shoreline supporting an extensive hydrophytic community. Submergent species present prior to soil collection were southern naiad, coontail, Chara vulgaris L. , and Potamogeton pusillus L. . Additionally, seed-bank 14 soil from B-6-3 was used effectively... during SEPT92 sampling period. Additionally, Potamogeton nodosus had a frequency of 0. 17 within SEED plots and was sampled most often (0. 15) in shelf I. Finally, Chara vulgaris, a complex algaphyte, was observed most frequently within SAGO plots (0...

Thomas, James Alan

2012-06-07

174

An inventory of 13 C abundances in coastal wetlands of Louisiana, USA: vegetation and sediments  

Microsoft Academic Search

Organic carbon-rich sediments from the surface of fresh, intermediate, brackish and salt marshes of coastal Louisiana were sampled and analyzed for their 13C content. The average ?13C from all sites within each wetland type was-27.8‰,-22.1‰,-16.9‰, and-16.2‰, for fresh, intermediate, brackish and salt marshes, respectively. Means from the fresh, intermediate and brackish marshes were significantly different at the 0.01 level. A

G. L. Chmura; P. Aharon; R. A. Socki; R. Abernethy

1987-01-01

175

Submerged aquatic vegetation-based treatment wetlands for removing phosphorus from agricultural runoff: response to hydraulic and nutrient loading.  

PubMed

Submerged aquatic vegetation (SAV) communities exhibit phosphorus (P) removal mechanisms not found in wetlands dominated by emergent macrophytes. This includes direct assimilation of water column P by the plants and pH-mediated P coprecipitation with calcium carbonate (CaCO3). Recognizing that SAV might be employed to increase the performance of treatment wetlands, we investigated P removal in mesocosms (3.7 m2) stocked with a mixture of taxa common to the region: Najas guadalupensis, Ceratophyllum demersum, Chara spp. and Potamogeton illinoensis. Three sets of triplicate mesocosms received agricultural runoff from June 1998 to February 2000 at nominal hydraulic retention times (HRTs) of 1.5, 3.5 or 7.0 days. Mean total P (TP) loading rates were 19.7. 8.3 and 4.5 g/m2/yr. After eight months of operation. N. guadalupensis dominated the standing crop biomass and P storage, whereas C. demersum exhibited the highest tissue P content. Chara spp. was prominent only in the 7.0)-day HRT treatments while P. illinoensis largely disappeared. Inflow soluble reactive phosphorus (SRP) (10 163 microg/L) was reduced consistently to near the detection limit (2 microg/L) in the 3.5- and 7.0-day HRT treatments, and to a mean of 9 microg/L in the 1.5-day HRT treatment. The mean inflow TP concentration (10(7) microg/L) was reduced to 52, 29 and 23 microg/L in the 1.5-, 3.5- and 7.0-day HRT treatments, respectively. Total P concentrations in new sediment (mean= 641, 408 and 459 mg/kg in the 1.5-. 3.5-, and 7.0-day HRT mesocosms, respectively) were much higher than in the muck soil used to stock the mesocosms (236 mg/ kg). The calcium content of new sediment was twice that of the muck soil (16.5% vs. 7.6%), demonstrating that CaCO3 production and, perhaps, coprecipitation of P occurred. We observed no nocturnal remobilization of SRP despite diel fluctuations in pH and dissolved oxygen. Mean outflow TP (21 microg/L) from a 147 ha SAV wetland (4-day nominal HRT) was similar to mean outflow TP in the 3.5-day and 7.0-day HRT treatments. The mesocosms adequately mimicked P removal and other important characteristics of the larger system and can be used to address research questions regarding treatment performance of full-scale SAV wetlands. Available data suggest that the incorporation of SAV communities into the stormwater treatment areas may benefit Everglades restoration. PMID:11996331

Dierberg, F E; DeBusk, T A; Jackson, S D; Chimney, M J; Pietro, K

2002-03-01

176

Integrated field lysimetry and porewater sampling for evaluation of chemical mobility in soils and established vegetation.  

PubMed

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals is often not well understood. Here we demonstrate an integrated field lysimetry and porewater sampling method for evaluating the mobility of chemicals applied to soils and established vegetation. Lysimeters, open columns made of metal or plastic, are driven into bareground or vegetated soils. Porewater samplers, which are commercially available and use vacuum to collect percolating soil water, are installed at predetermined depths within the lysimeters. At prearranged times following chemical application to experimental plots, porewater is collected, and lysimeters, containing soil and vegetation, are exhumed. By analyzing chemical concentrations in the lysimeter soil, vegetation, and porewater, downward leaching rates, soil retention capacities, and plant uptake for the chemical of interest may be quantified. Because field lysimetry and porewater sampling are conducted under natural environmental conditions and with minimal soil disturbance, derived results project real-case scenarios and provide valuable information for chemical management. As chemicals are increasingly applied to land worldwide, the described techniques may be utilized to determine whether applied chemicals pose adverse effects to human health or the environment. PMID:25045915

Matteson, Audrey R; Mahoney, Denis J; Gannon, Travis W; Polizzotto, Matthew L

2014-01-01

177

Least Bittern distribution among structurally different vegetation types in managed wetlands of northwest Tennessee, USA  

Microsoft Academic Search

We conducted Least Bittern (Ixobrychus exilis) surveys on Reelfoot Lake and nearby Black Bayou Waterfowl Refuge, in northwest Tennessee, USA during May–June 2003 to determine\\u000a the distribution of Least Bitterns among structurally different vegetation types, including giant cutgrass (Zizaniopsis miliacea), swamp loosestrife (Decodon verticillatus), and woody vegetation. Least Bitterns were historically abundant on Reelfoot Lake when giant cutgrass once occupied

Nicholas A. Winstead; Sammy L. King

2006-01-01

178

The influence of topography and vegetation self-organization over resource fluxes in wetland ecosystems  

NASA Astrophysics Data System (ADS)

While it is recognized that topography and vegetation self-organization (SO) are both first order controls over ecosystem dynamics, the discrete contributions that these two controls have over ecosystem functioning have not been studied in any rigorous way. This work is focused on systematically isolating the separate and combined impacts of topography and SO over vegetation dynamics. We simulate the steady state and transient dynamics of nitrogen-limited patterned peat vegetation observed in the bogs of northern Siberia. We do so across a realistic range of land slopes, nutrient limitation values, and rainfall amounts. Simulation results show that on relatively shallow slopes, vegetation SO is a primary control over the spatial arrangement of vegetation, and that such self-organized arrangements yield the most efficient capture of ecosystem resources. However, as slope increases, and or resource limitation is low, topography begins to exert its control over the temporal and spatial dynamics. As will be discussed, these results suggest a simple continuum framework, valid across biomes, for understanding the interplay between these two first order controls. Specifically, as resources (e.g., water, nutrients) increase, ecosystem dynamics shift towards topographic control, while when resources are reduced, ecosystem dynamics shift towards vegetation SO control.

Stieglitz, Marc; Cheng, Yiwei; Truk, Greg; Engel, Victor; Ross, Joshua

2014-05-01

179

Macrophyte colonization in a freshwater tidal wetland (Lyme, CT, USA)  

Microsoft Academic Search

Seed bank sampling and creation of plots cleared of standing vegetation showed that aboveground vegetative propagules were more important than seeds in colonization of a freshwater tidal wetland but that the relative importance of sexual reproduction varied among species. Nine submerged species established in colonization plots. Of these colonization events, 60% were achieved by plant fragments, either in the sediment

Robert S. Capers

2003-01-01

180

Comparison of disturbed and undisturbed wetland communities using vegetation, aquatic macroinvertebrate and landscape analyses  

E-print Network

by permanent markers left from one season to the next. Within this defined area all the vegetation was sampled, in late May 1994, by counting stems above the water or soil. In the case of Eleocharis, a clump of stems was counted as one. Non-vascular plants... by permanent markers left from one season to the next. Within this defined area all the vegetation was sampled, in late May 1994, by counting stems above the water or soil. In the case of Eleocharis, a clump of stems was counted as one. Non-vascular plants...

Perry, Irene H

2012-06-07

181

The influence of light availability on competition between Phalaris arundinacea and a native wetland sedge  

Microsoft Academic Search

Invasions by Phalaris arundinacea (reed canarygrass) preclude establishment of sedge meadow vegetation in restored wetlands in the midwest USA. To evaluate cover crops as a potential method of P. arundinacea control, we examined the effects of lowering light availability (from 600 to 200 and 10 µmol m-2 s-1) on competition between P. arundinacea and a common wetland sedge, Carex hystericina

Laura G. Perry; Susan M. Galatowitsch

2004-01-01

182

Assessment of acreage and vegetation change in Florida's Big Bend tidal wetlands using satellite imagery  

USGS Publications Warehouse

Fluctuations in sea level and impending development on the west coast of Florida have aroused concern for the relatively pristine tidal marshes of the Big Bend. Landsat Thematic Mapper (TM) images for 1986 and 1995 are processed and evaluated for signs of change. The images cover 250 km of Florida's Big Bend Gulf Coast, encompassing 160,000 acres of tidal marshes. Change is detected using the normalized difference vegetation index (NDVI) and land cover classification. The imagery shows negligible net loss or gain in the marsh over the 9-year period. However, regional changes in biomass are apparent and are due to natural disturbances such as low winter temperatures, fire, storm surge, and the conversion of forest to march. Within the marsh, the most prominent changes in NDVI and in land cover result from the recovery of mangroves from freezes, a decline of transitional upland vegetation, and susceptibility of the marsh edge and interior to variations in tidal flooding.

Raabe, Ellen A.; Stumpf, Richard P.

1997-01-01

183

Germination in Baltic coastal wetland meadows: similarities and differences between vegetation and seed bank  

Microsoft Academic Search

The abundance and variety of seedlings in Baltic coastal grasslands was studied in cattle grazed and ungrazed areas in seashore\\u000a and delta on the western coast of Finland. The vegetation, seed bank and environmental conditions of the same sites were also\\u000a studied. Altogether 4609 seedlings were observed in 79 field plots (20 cm 20 cm) making an average of 1458.54

Heli M. Jutila

2003-01-01

184

Seed banks of a river–reservoir wetland system and their implications for vegetation development  

Microsoft Academic Search

The Danjiangkou Reservoir, constructed in 1970s, is the water source area of the middle route of China's interbasin South-to-North Water Transfer Project. To serve such purpose, the Danjiangkou Reservoir Dam will be increased from its present 162.0m to 176.6m, and its regular water level from 157m to 170m above mean sea level. Vegetation development in the new reservoir margins is

Wenzhi Liu; Quanfa Zhang; Guihua Liu

2009-01-01

185

Wetlands International  

NSDL National Science Digital Library

Established as a non-governmental organization, Wetlands International is concerned with promoting the conservation and wise use of wetlands on the global, regional, and national levels. Much of the information on the site is contained within a dozen or so sections along the left-hand side of the homepage. First-time visitors may want to read through the "About Us" area before proceeding to the "Introduction to Wetlands" area. Scholars and policy analysts will want to also look through the "Publications" area. Here they will find information sheets on peatland loss, user handbooks on various wetland regions, and related fact sheets for general use. Visitors may also want to peruse the "Biodiversity Programmes" area to learn more about the species and habitats that Wetlands International works to preserve through their advocacy work. The site is rounded out by a collection of recent news stories and press releases.

186

Mapping the Wetland Vegetation Communities of the Australian Great Artesian Basin Springs Using SAM, Mtmf and Spectrally Segmented PCA Hyperspectral Analyses  

NASA Astrophysics Data System (ADS)

The Australian Great Artesian Basin (GAB) supports a unique and diverse range of groundwater dependent wetland ecosystems termed GAB springs. In recent decades the ecological sustainability of the springs has become uncertain as demands on this iconic groundwater resource increase. The impacts of existing water extractions for mining and pastoral activities are unknown. This situation is compounded by the likelihood of future increasing demand for extractions. Hyperspectral remote sensing provides the necessary spectral and spatial detail to discriminate wetland vegetation communities. Therefore the objectives of this paper are to discriminate the spatial extent and distribution of key spring wetland vegetation communities associated with the GAB springs evaluating three hyperspectral techniques: Spectral Angle Mapper (SAM), Mixture Tuned Matched Filtering (MTMF) and Spectrally Segmented PCA. In addition, to determine if the hyperspectral techniques developed can be applied at a number of sites representative of the range of spring formations and geomorphic settings and at two temporal intervals. Two epochs of HyMap airborne hyperspectral imagery were captured for this research in March 2009 and April 2011 at a number of sites representative of the floristic and geomorphic diversity of GAB spring groups/complexes within South Australia. Colour digital aerial photography at 30 cm GSD was acquired concurrently with the HyMap imagery. The image acquisition coincided with a field campaign of spectroradiometry measurements and a botanical survey. To identify key wavebands which have the greatest capability to discriminate vegetation communities of the GAB springs and surrounding area three hyperspectral data reduction techniques were employed: (i) Spectrally Segmented PCA (SSPCA); (ii) the Minimum Noise Transform (MNF); and (iii) the Pixel Purity Index (PPI). SSPCA was applied to NDVI-masked vegetation portions of the HyMap imagery with wavelength regions spectrally segmented for the VIS-NIR (450-1,350 nm), SWIR 1 (1,400-1,800 nm) and SWIR 2 (1,950-2,480 nm). The resulting pure endmember image pixels of the vegetation communities identified were used as target spectra for input into the SAM and MTMF algorithms. Spring wetland vegetation communities successfully discriminated include low lying reeds and sedges along spring tails (Baumea spp. and Cyperus spp.), dense homogenous stands of Phragmites australis reeds, and sporadic patches of salt couch grass (Sparabolus spp.). Our results indicate that a combination of hyperspectral remote sensing techniques which reduce superfluous wavebands providing a targeted spectral matching approach are capable of discriminating and mapping key vegetation communities of the GAB springs. This approach provides reliable baseline mapping of the GAB spring wetland vegetation communities, with repeatability over space and time. In addition it has the capability to determine the sensitivity of spring wetland vegetation extent, distribution and diversity, to associated changes in spring flow rates due to water extractions. This approach will ultimately inform water allocation plan management policies.

White, D. C.; Lewis, M. M.

2012-07-01

187

Effects of vegetative propagule pressure on the establishment of an introduced clonal plant, Hydrocotyle vulgaris  

PubMed Central

Some introduced clonal plants spread mainly by vegetative (clonal) propagules due to the absence of sexual reproduction in the introduced range. Propagule pressure (i.e. total number of propagules) may affect the establishment and thus invasion success of introduced clonal plants, and such effects may also depend on habitat conditions. A greenhouse experiment with an introduced plant, Hydrocotyle vulgaris was conducted to investigate the role of propagule pressure on its invasion process. High (five ramets) or low (one ramet) propagule pressure was established either in bare soil or in an experimental plant community consisting of four grassland species. H. vulgaris produced more total biomass under high than under low propagule pressure in both habitat conditions. Interestingly, the size of the H. vulgaris individuals was smaller under high than under low propagule pressure in bare soil, whereas it did not differ between the two propagule pressure treatments in the grassland community. The results indicated that high propagule pressure can ensure the successful invasion in either the grass community or bare soil, and the shift in the intraspecific interaction of H. vulgaris from competition in the bare soil to facilitation in the grassland community may be a potential mechanism. PMID:24981102

Liu, Ruihua; Chen, Qiuwen; Dong, Bicheng; Yu, Feihai

2014-01-01

188

Effects of vegetative propagule pressure on the establishment of an introduced clonal plant, Hydrocotyle vulgaris.  

PubMed

Some introduced clonal plants spread mainly by vegetative (clonal) propagules due to the absence of sexual reproduction in the introduced range. Propagule pressure (i.e. total number of propagules) may affect the establishment and thus invasion success of introduced clonal plants, and such effects may also depend on habitat conditions. A greenhouse experiment with an introduced plant, Hydrocotyle vulgaris was conducted to investigate the role of propagule pressure on its invasion process. High (five ramets) or low (one ramet) propagule pressure was established either in bare soil or in an experimental plant community consisting of four grassland species. H. vulgaris produced more total biomass under high than under low propagule pressure in both habitat conditions. Interestingly, the size of the H. vulgaris individuals was smaller under high than under low propagule pressure in bare soil, whereas it did not differ between the two propagule pressure treatments in the grassland community. The results indicated that high propagule pressure can ensure the successful invasion in either the grass community or bare soil, and the shift in the intraspecific interaction of H. vulgaris from competition in the bare soil to facilitation in the grassland community may be a potential mechanism. PMID:24981102

Liu, Ruihua; Chen, Qiuwen; Dong, Bicheng; Yu, Feihai

2014-01-01

189

Transpiration of gaseous elemental mercury through vegetation in a subtropical wetland in Florida  

NASA Astrophysics Data System (ADS)

Four seasonal sampling campaigns were carried out in the Florida Everglades to measure elemental Hg vapor (Hg°) fluxes over emergent macrophytes using a modified Bowen ratio gradient approach. The predominant flux of Hg° over both invasive cattail and native sawgrass stands was emission; mean day time fluxes over cattail ranged from ˜20 (winter) to ˜40 (summer) ng m -2 h -1. Sawgrass fluxes were about half those over cattail during comparable periods. Emission from vegetation significantly exceeded evasion of Hg° from the underlying water surface (˜1-2 ng m -2 h -1) measured simultaneously using floating chambers. Among several environmental factors (e.g. CO 2 flux, water vapor flux, wind speed, water, air and leaf temperature, and solar radiation), water vapor exhibited the strongest correlation with Hg° flux, and transpiration is suggested as an appropriate term to describe this phenomenon. The lack of significant Hg° emissions from a live, but uprooted (floating) cattail stand suggests that a likely source of the transpired Hg° is the underlying sediments. The pattern of Hg° fluxes typically measured indicated a diel cycle with two peaks, possibly related to different gas exchange dynamics: one in early morning related to lacunal gas release, and a second at midday related to transpiration; nighttime fluxes approached zero.

Lindberg, Steve E.; Dong, Weijin; Meyers, Tilden

190

Transpiration of gaseous elemental mercury through vegetation in a subtropical wetland in florida  

SciTech Connect

Four seasonal sampling campaigns were carried out in the Florida Everglades to measure elemental Hg vapor (Hg{sup o}) fluxes over emergent macrophytes using a modified Bowen ratio gradient approach. The predominant flux of Hg{sup o} over both invasive cattail and native sawgrass stands was emission; mean day time fluxes over cattail ranged from {approx}20 (winter) to {approx}40 (summer) ng m{sup -2} h{sup -1}. Sawgrass fluxes were about half those over cattail during comparable periods. Emission from vegetation significantly exceeded evasion of Hg{sup o} from the underlying water surface ({approx}1-2 ng m{sup -2} h{sup -1}) measured simultaneously using floating chambers. Among several environmental factors (e.g. CO{sub 2} flux, water vapor flux, wind speed, water, air and leaf temperature, and solar radiation), water vapor exhibited the strongest correlation with Hg{sup o} flux, and transpiration is suggested as an appropriate term to describe this phenomenon. The lack of significant Hg{sup o} emissions from a live, but uprooted (floating) cattail stand suggests that a likely source of the transpired Hg{sup o} is the underlying sediments. The pattern of Hg{sup o} fluxes typically measured indicated a diel cycle with two peaks, possibly related to different gas exchange dynamics: one in early morning related to lacunal gas release, and a second at midday related to transpiration; nighttime fluxes approached zero.

Lindberg, Steven Eric [ORNL; Dong, Weijin [ORNL; Meyers, Tilden [NOAA, Oak Ridge, TN

2002-07-01

191

Integrated surface-ground water modeling in wetlands with improved methods to simulate vegetative resistance to flow  

Microsoft Academic Search

In topographically flat wetlands, where shallow water table and conductive soil may develop as a result of wet and dry seasons, the connection between surface water and groundwater is not only present, but perhaps the key factor dominating the magnitude and direction of water flux. Due to their complex characteristics, modeling waterflow through wetlands using more realistic process formulations (integrated

Mauro Nalesso

2009-01-01

192

Soil bacterial community structure and physicochemical properties in mitigation wetlands created in the Piedmont region of Virginia (USA)  

Microsoft Academic Search

Wetland creation is a common practice for compensatory mitigation in the United States. Vegetation attributes have been used as a quick measure of mitigation success in most post-creation monitoring, while little attention has been paid to soils that provide the substrate for flora and fauna to establish and develop. Created wetland soils are often found not indicative of ‘hydric soil’

Changwoo Ahn; Rita M. Peralta

2009-01-01

193

Application of remote sensing techniques at different scales of observation on wetland evapotranspiration  

NASA Astrophysics Data System (ADS)

The establishment and maintenance of the structure and functions in wetland ecosystems is greatly influenced by hydrologic conditions. Evapotranspiration (ET) is the major output component in the hydrologic water budget. Therefore, in order to provide efficient information for water resources management and the conservation of wetland ecosystems, research on ET is urgently needed. Moreover, to overcome the variable spatial vegetation distribution and the temporal change of wetlands, appropriate remote sensing techniques are also greatly needed. The goal of this research was to study fundamental wetland ET and then with the aid of remote sensing techniques from the micro scale to the macro scale to develop useful wetland ET estimation methods. The study site was located in the Ft. Drum Marsh, Upper St. John's River Basin in Indian River County, Florida. The site is a freshwater marsh with southern cattail ( Typha domingensis Pers.) and sawgrass (Cladium jamaicense Crantz) as the dominant vegetation species. There were four stages of the study: (1) a fundamental ET study with a lysimeter system, (2) ground measurements and analyses of spectral responses of wetland vegetation using a field spectroradiometer, (3) wetland vegetation mapping using aerial hyperspectral images, and (4) application of satellite images to delineate wetland vegetation and estimate marsh-wide ET. The results of the fundamental ET study showed the various important vegetation parameters of sawgrass and cattail. A more appropriate estimation method of canopy resistance for sawgrass and cattail was proposed. Among the various ET estimation methods, the Priestley-Taylor method was found to be most applicable. The ground spectral response measurements of sawgrass and cattail demonstrated a distinguishable difference in red wavebands and normalized difference vegetation index (NDVI), which indicated the spectral separability of the two wetland species. Leaf area index and stomatal resistance displayed a high correlation to spectral reflectance. Aerial hyperspectral imaging proved very successful in the identification of wetland vegetation species. Among all 64 wavebands, the separability tests revealed that the wavebands in the blue-green, red edge, and near-infrared spectral regions are the most important contributors for the identification of wetland vegetation species. The satellite image was applied to map wetland vegetation using the knowledge based classification method. Integrating the results from the four stages of study, the marsh-wide ET was estimated. The results of this research can have extensive application to wetland ET, wetland delineation, and remote sensing techniques.

Juan, Chung-Hsin

194

Pipeline Corridors through wetlands -- Impacts on plant communities: Mill Creek Tributary Crossing, Jefferson County, New York, 1992 Survey  

SciTech Connect

The goal of the Gas Research Institute Wetland Corridors Program is to identify representative impacts of existing pipelines on the wetlands they traverse. To accomplish this goal, 12 existing wetland crossings were surveyed. These sites varied in elapsed time since pipeline construction, wetland type, pipeline installation techniques, and right-of-way (ROW) management practices. This report presents the results of the survey July 1992, at the Mills Creek tributary crossing, Jefferson County, New York. Data were collected from three wetland communities along the 1991 pipeline and compared with predisturbance data obtained in a June 1991 survey. Within one year after pipeline installation, 50% of the soil surface of the ROW in the scrub-shrub community was covered by emergent vegetation. Average wetland values for the ROW in 1992 were lower than in 1991, indicating that the removal of woody plants resulted in a community composed of species with greater fidelity to wetlands. In the emergent marsh community after one year, the average percentage of surface covered by standing water was greater in the ROW than in the adjacent natural areas. The ROW in the forested wetland community also contained standing water, although none was found in the natural forest areas. The entire study site remains a wetland, with the majority of plant species in all sites being either obligate or facultative wetland species. Weighted and unweighted average wetland indices for each community, using all species, indicated wetland vegetation within the newly established ROW.

Van Dyke, G.D. [Trinity Christian Coll., Palos Heights, IL (United States). Dept. of Biology; Shem, L.M.; Zimmerman, R.E. [Argonne National Lab., IL (United States)

1994-12-01

195

Mile High Wetland Bank  

NSDL National Science Digital Library

The site listed here is provided by an environmental consulting firm that works with commercial and private landowners to establish Wetland Banks. An innovative concept (and growing reality) that has received mixed reviews from scientists, Wetland Banking attempts to combine the goals of developers (i.e., to develop a certain area) and wetland conservationists (i.e., to maintain/ restore areas of intact wetlands). If misused, this approach could work against wetland conservation; if properly instated, however, Wetland Banking might offer an alternative to the currently poor success rate of wetland mitigation projects. This resource by Mile High Wetlands Group, LLC, offers background information on Wetland banking, with an emphasis on the Group's local area (Colorado).

196

Establishment, Protection, and Reestablishment of Urban Roadside Vegetation against Salt and Ice.  

National Technical Information Service (NTIS)

The use of salt as a de-icer is common in Minnesota, because of its low cost and efficiency. But it causes many problems for highway maintenance staff because of its impact on the adjacent vegetation. Salty soils are not conducive to healthy vegetation gr...

A. M. Johnson

2000-01-01

197

The effects of size of opening in vegetation and litter cover on seedling establishment of goldenrods ( Solidago spp.)  

Microsoft Academic Search

We investigated the effects of size of opening in the vegetation and litter cover on seedling establishment of two species of goldenrods (Solidago spp.) in an abandoned field in southwestern Michigan, U.S.A. Seeds of S. canadensis and S. juncea were sown into clipped plots, ranging from 0 cm (control, unclipped) to 100 cm in diameter, with and without litter. Seedling

Deborah E. Goldberg; Patricia A. Werner

1983-01-01

198

Vegetation community responses to different establishment regimes in loblolly pine ( Pinus taeda) plantations in southern MS, USA  

Microsoft Academic Search

Management treatments involving multiple herbicide applications are standard procedure on most industrial pine plantation sites in the southern USA, raising concerns about biodiversity impairment. Management decisions impact not only plant communities but also the habitat potential they create for wildlife. We tested the effects of five intensities of stand establishment treatments on vegetation communities in loblolly pine plantations (n=4) to

Phillip D. Jones; Scott L. Edwards; Stephen Demarais; Andrew W. Ezell

2009-01-01

199

Isolated Spring Wetlands in the Great Basin and Mojave Deserts, USA: Potential Response of Vegetation to Groundwater Withdrawal  

Microsoft Academic Search

Desert springs, often the sole sources of water for wildlife and cattle, support wetland and wetland\\/upland transition ecosystems\\u000a including rare and endemic species. In the basin and range province in Nevada, USA, springs in the Great Basin and Mojave\\u000a deserts are sustained by interconnected deep carbonate and shallow basin-fill aquifers which are threatened by proposed groundwater\\u000a withdrawal to sustain rapidly

Duncan T. Patten; Leigh Rouse; Juliet C. Stromberg

2008-01-01

200

Assessment of compost application to coal ash disposal sites to promote the rapid vegetation establishment  

NASA Astrophysics Data System (ADS)

In the city of Tuzla, located in Bosnia and Herzegovina, a coal fired thermo electric power plant is operated by the company JP ELEKTROPRIVERDA BIH TERMOELEKTRANA "TUZLA". High amounts of ash are produced by the power plant, which are currently disposed into settlement ponds bordered by dams in natural valleys. A total of four ash disposal sites covering an area of approx. 170 ha have been established during the last decades. Due to the fact that residual ash from coal combustion was found to contain a variety of trace elements (Ni, Cr, As, B), it must be assumed that ash disposal of that magnitude constitutes an environmental problem which is investigated within the EU-FP6 / STREP project "Reintegration of Coal Ash Disposal Sites and Mitigation of Pollution in the West Balkan Area" RECOAL. The main hazards relate to soil and groundwater contamination due to leaching toxins, dust dispersion, and toxins entering the food chain as these disposal sites are used for agricultural purposes. In order to rapidly establish a vegetation cover on barren ash dumps that particularly would prevent dust erosion we assessed the applicability of compost, produced from locally available municipal and industrial organic residues as an amendment to ash to improve substrate fertility. The envisaged remediation technology was considered to be a low cost, easy applicable and rapid method capable of substantially enhancing living conditions of residents in the vicinity of the abandoned disposal sites. Various compost application rates were evaluated in the field on experimental site Divkovici I in Tuzla and additionally in the greenhouse environment at Brandenburg Technical University Cottbus. Field and laboratory tests revealed that plant growth and cover rate can substantially be improved by mixing compost into the upper ash layer to a maximum depth of approx. 20 cm. Besides direct growth observations in the field analysis of soil parameters gave evidence that the fertility of ashy substrates amended with compost produced from locally available sewage sludge and saw dust can be improved. The metal content of grass grown in the various treatments was considered to be elevated compared to normal contents. However, metal uptake in compost treatments was lower than in untreated plots. A preliminary cost assessment, comparing the remediation technology tested on site Divkovici with a standard soil covering technique revealed financial benefits for the compost method due to significant lower application rates.

Repmann, F.; Slazak, A.; Babic, M.; Schneider, B. U.; Schaaf, W.; Hüttl, R. F.

2009-04-01

201

Reducing sedimentation of depressional wetlands in agricultural landscapes  

USGS Publications Warehouse

Depressional wetlands in agricultural landscapes are easily degraded by sediments and contaminants accumulated from their watersheds. Several best management practices can reduce transport of sediments into wetlands, including the establishment of vegetative buffers. We summarize the sources, transport dynamics, and effect of sediments, nutrients, and contaminants that threaten wetlands and the current knowledge of design and usefulness of grass buffers for protecting isolated wetlands. Buffer effectiveness is dependent on several factors, including vegetation structure, buffer width, attributes of the surrounding watershed (i.e., area, vegetative cover, slope and topography, soil type and structure, soil moisture, amount of herbicides and pesticides applied), and intensity and duration of rain events. To reduce dissolved contaminants from runoff, the water must infiltrate the soil where microbes or other processes can break down or sequester contaminants. But increasing infiltration also diminishes total water volume entering a wetland, which presents threats to wetland hydrology in semi-arid regions. Buffer effectiveness may be enhanced significantly by implementing other best management practices (e.g., conservation tillage, balancing input with nutrient requirements for livestock and crops, precision application of chemicals) in the surrounding watershed to diminish soil erosion and associated contaminant runoff. Buffers require regular maintenance to remove sediment build-up and replace damaged or over-mature vegetation. Further research is needed to establish guidelines for effective buffer width and structure, and such efforts should entail a coordinated, regional, multi-scale, multidisciplinary approach to evaluate buffer effectiveness and impacts. Direct measures in "real-world" systems and field validations of buffer-effectiveness models are crucial next steps in evaluating how grass buffers will impact the abiotic and biotic variables attributes that characterize small, isolated wetlands. ?? 2008 The Society of Wetland Scientists.

Skagen, S. K.; Melcher, C. P.; Haukos, D. A.

2008-01-01

202

White Ranch Wetlands Biological Survey  

E-print Network

White Ranch Wetlands Biological Survey and Permanent Vegetation Monitoring Plots Prepared for: U Services Building Colorado State University Fort Collins, CO 80523 March 1998 #12;WHITE RANCH WETLANDS assessment of the White Ranch wetlands. In addition we set up permanent plots along transects to collect

203

Numerical modeling of the effects of water flow, sediment transport and vegetation growth on the spatiotemporal patterning of the ridge and slough landscape of the Everglades wetland  

NASA Astrophysics Data System (ADS)

A numerical model has been developed to simulate the spatiotemporal patterning of the ridge and slough landscape in wetlands, characterized by crests (ridges) and valleys (sloughs) that are elongated parallel to the direction of water flow. The model formulation consists of governing equations for integrated surface water and groundwater flow, sediment transport, and soil accretion, as well as litter production by vegetation growth. The model simulations show how the spatial pattern self-organizes over time with the generation of ridges and sloughs through sediment deposition and erosion driven by the water flow field. The spatial and temporal distributions of the water depth, flow rates and sediment transport processes are caused by differential flow due to vegetation and topography heterogeneities. The model was parameterized with values that are representative of the Everglades wetland in the southern portion of the Florida peninsula in the USA. Model simulation sensitivity was tested with respect to numerical grid size, lateral vegetation growth and the rate of litter production. The characteristic wavelengths of the pattern in the directions along and perpendicular to flow that are simulated with this model develop over time into ridge and slough shapes that resemble field observations. Also, the simulated elevation differences between the ridges and sloughs are of the same order of those typically found in the field. The width of ridges and sloughs was found to be controlled by a lateral vegetation growth distance parameter in a simplified formulation of vegetation growth, which complements earlier modeling results in which a differential peat accretion mechanism alone did not reproduce observations of ridge and slough lateral wavelengths. The results of this work suggest that ridge and slough patterning occurs as a result of vegetation's ability to grow laterally, enhancing sediment deposition in ridge areas, balanced by increased sediment erosion in slough areas to satisfy flow continuity. The interplay between sediment transport, water flow and vegetation and soil dynamic processes needs to be explored further through detailed field experiments, using a model formulation such as the one developed in this work to guide data collection and interpretation. This should be one of the focus areas of future investigations of pattern formation and stability in ridge and slough areas.

Lago, Marcelo E.; Miralles-Wilhelm, Fernando; Mahmoudi, Mehrnoosh; Engel, Vic

2010-10-01

204

Effects of a Long-Term Disturbance on Arthropods and Vegetation in Subalpine Wetlands: Manifestations of Pack Stock Grazing in Early versus Mid-Season  

PubMed Central

Conclusions regarding disturbance effects in high elevation or high latitude ecosystems based solely on infrequent, long-term sampling may be misleading, because the long winters may erase severe, short-term impacts at the height of the abbreviated growing season. We separated a) long-term effects of pack stock grazing, manifested in early season prior to stock arrival, from b) additional pack stock grazing effects that might become apparent during annual stock grazing, by use of paired grazed and control wet meadows that we sampled at the beginning and end of subalpine growing seasons. Control meadows had been closed to grazing for at least two decades, and meadow pairs were distributed across Sequoia National Park, California, USA. The study was thus effectively a landscape-scale, long-term manipulation of wetland grazing. We sampled arthropods at these remote sites and collected data on associated vegetation structure. Litter cover and depth, percent bare ground, and soil strength had negative responses to grazing. In contrast, fauna showed little response to grazing, and there were overall negative effects for only three arthropod families. Mid-season and long-term results were generally congruent, and the only indications of lower faunal diversity on mid-season grazed wetlands were trends of lower abundance across morphospecies and lower diversity for canopy fauna across assemblage metrics. Treatment x Season interactions almost absent. Thus impacts on vegetation structure only minimally cascaded into the arthropod assemblage and were not greatly intensified during the annual growing season. Differences between years, which were likely a response to divergent snowfall patterns, were more important than differences between early and mid-season. Reliance on either vegetation or faunal metrics exclusively would have yielded different conclusions; using both flora and fauna served to provide a more integrative view of ecosystem response. PMID:23308297

Holmquist, Jeffrey G.; Schmidt-Gengenbach, Jutta; Haultain, Sylvia A.

2013-01-01

205

Land use and riparian effects on prairie wetland sediment properties and herbicide sorption coefficients.  

PubMed

Sorption of commonly used herbicides by wetland sediment can provide important information for herbicide fate modeling. The influence of sediment properties on herbicide sorption as a result of different land uses in the wetland catchment is unclear. We examined the effects of land use on the physiochemical properties of wetland sediments and the associations between these sediment properties and herbicide sorption characteristics. Bottom sediments were sampled in 0- to 5- and 5- to 10-cm sections from 17 wetlands under five different land use classes: (i) ephemeral wetlands with no riparian vegetation in a cultivated catchment (ECNR), (ii) ephemeral wetlands with riparian vegetation in a cultivated catchment (ECR), (iii) ephemeral wetlands in a grassland catchment established 4 yr ago (E4G), (iv) ephemeral wetlands in a brome grass catchment established 20 yr ago (E20G), and (v) semi-permanent (SP) wetlands in a multiple-land-use catchment. Sediments were analyzed for total organic carbon (TOC), total inorganic carbon (TIC), pH, electrical conductivity, exchangeable cations (EXCAT), total cation exchangeable capacity (CEC), and percent clay (%clay). Sediment herbicide sorption partition coefficient (Kd) was measured for trifluralin, atrazine, 2,4-D, and glyphosate. The sorption of the herbicides in the sediment increased in the order of 2,4-D < atrazine < glyphosate < trifluralin. The sorption of 2,4-D, atrazine, and trifluralin was positively correlated to TOC, EXCAT, and CEC but negatively correlated to %clay. Glyphosate sorption was negatively correlated to pH, TIC, EXCAT, and %clay. Overall, wetland sediments that were recently cultivated (ECNR and E4G) had lower TOC, TIC, EC, EXCAT, CEC, and Kd values (2,4-D, trifluralin, and atrazine) than sediments that had not been recently cultivated (ECR, E20G, and SP). The ECR wetland sediments had the largest Kd for all four herbicides, suggesting that land use and riparian vegetation have a significant impact on herbicide sorption. PMID:19549953

Xu, Dani; Meyer, Sheila; Gaultier, Jeanette; Farenhorst, Annemieke; Pennock, Dan

2009-01-01

206

The Carolina Bay Restoration Project: Implementation and Management of a Wetland Mitigation Bank.  

SciTech Connect

A wetlands Mitigation Bank was established at the Savannah River Site (SRS) in 1997 as a compensatory alternative for unavoidable wetland losses associated with future authorized construction and environmental restoration projects in SRS wetlands. The Bank was intended not only to hasten mitigation efforts with respect to regulatory requirements and implementation, but also to provide onsite and fully functional compensation of impacted wetland acreage prior to any impact. Restoration and enhancement of small isolated wetlands, as well as major bottomland wetland systems scattered throughout the nonindustrialized area of SRS were designated for inclusion in the Bank. Based on information and techniques gained from previous research efforts involving Carolina bay wetlands (DOE 1997), a project to restore degraded Carolina bays on SRS has been undertaken to serve as the initial ''deposit'' in The Bank. There are over 300 Carolina bays or bay-like depression wetlands on the SRS, of which an estimated two-thirds were ditched or disturbed prior to federal occupation of the Site (Kirkman et al., 1996). These isolated wetlands range from small ephemeral depressions to large permanent ponds of 10-50 hectares in size. They provide habitat to support a wide range of rare plant species, and many vertebrates (birds, amphibians, bats). Historical impacts to the Carolina bays at SRS were primarily associated with agricultural activities. Bays were often drained tilled and planted to crops. The consequence was a loss in the wetland hydrologic cycle, the native wetland vegetation, and associated wildlife. The purpose of this mitigation and research project is to restore the functions and vegetation typical of intact depression wetlands and, in doing so, to enhance habitat for wetland dependent wildlife on SRS.

Barton, Christopher; DeSteven, Diane; Sharitz, Rebecca; Kilgo, John; Imm, Donald; Kolka, Randy; Blake, John, I.

2003-01-01

207

Bark mulch promotes establishment of vegetation on minesoils with south and west exposures  

Microsoft Academic Search

In early July 1976, a non-topsoiled head-of-hollow fill in Breathitt County, Kentucky, was seeded to grasses and legumes. From July 12 to July 16, a hardwood bark mulch was applied in a band around this fill. After late August 1976, the mulched areas were nearly fully sodded, regardless of aspect. South- and west-facing unmulched slopes were nearly void of vegetation.

K. L. Dyer; J. C. Sencindiver

1985-01-01

208

Wetlands in the Venetian Po Plain (northeastern Italy) during the Last Glacial Maximum: Interplay between vegetation, hydrology and sedimentary environment  

Microsoft Academic Search

In the low Venetian plain (northeastern Italy) thick sequences of silt and sand layers alternate with common, thin layers of peat and organic silt; the organic layers in the topmost 30 m of the Late Pleistocene alluvial series span between 23,000 and 14,000 yr BP (radiocarbon dating), in an area measuring 100 km by 30 km. They indicate broad areas where wetlands developed. We

A. Miola; A. Bondesan; L. Corain; S. Favaretto; P. Mozzi; S. Piovan; I. Sostizzo

2006-01-01

209

Differences in flooding tolerance between species from two wetland habitats with contrasting hydrology: implications for vegetation development in future floodwater retention areas  

PubMed Central

Background and Aims Plants need different survival strategies in habitats differing in hydrological regimes. This probably has consequences for vegetation development when former floodplain areas that are currently confronted with soil flooding only, will be reconnected to the highly dynamical river bed. Such changes in river management are increasingly important, especially at locations where increased water retention can prevent flooding events in developed areas. It is therefore crucial to determine the responses of plant species from relatively low-dynamic wetlands to complete submergence, and to compare these with those of species from river forelands, in order to find out what the effects of such landscape-scale changes on vegetation would be. Methods To compare the species' tolerance to complete submergence and their acclimation patterns, a greenhouse experiment was designed with a selection of 19 species from two contrasting sites: permanently wet meadows in a former river foreland, and frequently submerged grasslands in a current river foreland. The plants were treated with short (3 weeks) and long (6 weeks) periods of complete submergence, to evaluate if survival, morphological responses, and changes in biomass differed between species of the two habitats. Key Results All tested species inhabiting river forelands were classified as tolerant to complete submergence, whereas species from wet meadows showed either relatively intolerant, intermediate or tolerant responses. Species from floodplains showed in all treatments stronger shoot elongation, as well as higher production of biomass of leaves, stems, fine roots and taproots, compared with meadow species. Conclusions There is a strong need for the creation of temporary water retention basins during high levels of river discharge. However, based on the data presented, it is concluded that such reconnection of former wetlands (currently serving as meadows) to the main river bed will strongly influence plant species composition and abundance. PMID:18836190

Banach, Katarzyna; Banach, Artur M.; Lamers, Leon P. M.; De Kroon, Hans; Bennicelli, Riccardo P.; Smits, Antoine J. M.; Visser, Eric J. W.

2009-01-01

210

Patterns in the secondary succession of a Carex vesicaria L. wetland following a permanent drawdown  

Microsoft Academic Search

The Myrkdalen Lake, western Norway, was subjected to a ca. 1.4m permanent drawdown in June 1987. This left the original wetland vegetation belts “hanging” over the new water level. One year after the drawdown, a permanent transect with contiguous 1.0m×0.5m quadrats was established through a Carex vesicaria wetland belt, and was analysed annually through 2001. The transect was 17m long

Arvid Odland

2002-01-01

211

The potential use of storm water and effluent from a constructed wetland for re-vegetating a degraded pyrite trail in Queen Elizabeth National Park, Uganda  

NASA Astrophysics Data System (ADS)

During the operation of the Kilembe Mines (copper mining) a cobaltiferous stockpile was constructed, which began to erode after the closure of the mines in the early 1970s. The erosion of the pyrite stockpile resulted in a large acid trail all the way to Lake George (a Ramsar site). The acid trail contaminated a large area of Queen Elizabeth National Park (QENP) resulting in the death of most of the shallow-rooted vegetation. Processes and conditions created by storm water and effluent from a constructed wetland were assessed for vegetation regeneration in the degraded QENP pyrite trail. Cynodon dactylon, Imperata cylindrica and Hyparrhenia filipendula dominated the regeneration zone (RZ) where storm water and effluent from a constructed wetland was flowing; and the adjacent unpolluted area (UP) with importance value indices of 186.4 and 83.3 respectively. Typha latifolia and C. dactylon formed two distinct vegetation sub-zones within the RZ with the former inhabiting areas with a higher water table. Soil pH was significantly higher in the RZ, followed by UP and bare pyrite trail (BPT) at both 0-15 cm and 16-30 cm depths. Soil electrical conductivity was not significantly different in the RZ and BPT but significantly higher than that in UP for both depths. For 0-15 cm depth, RZ had significantly higher concentrations of copper than BPT and UP which had similar concentrations. Still at this depth (0-15 cm), the unpolluted area had significantly higher concentrations of total phosphorus and total nitrogen than the regeneration zone and the bare pyrite trail which had similar concentrations. The RZ dominated by Typha had significantly higher concentrations of TP and TN compared to the RZ dominated by Cynodon. The concentrations of NH 4-N were significantly lower in Typha regeneration zone than in CRZ at 0-15 cm depth but similar at 16-30 cm depth. At 16-30 cm depth, concentrations of copper were significantly higher in the regeneration zone followed by the bare pyrite trail and the unpolluted zone. The concentration of lead in the regeneration zone and bare pyrite trail were similar but significantly higher in the unpolluted zone. Concentrations of TP and TN were significantly higher in unpolluted zone, followed by regeneration zone and bare pyrite trail. Storm water and effluent from a constructed wetland enhanced the revegetation process by modifying soil pH, making plant growth nutrients available and by providing a steady supply of moisture necessary for plant growth. T. latifolia and C. dactylon which seem to have tolerance of high concentrations of metals were the dominant species in the regeneration zone. If storm water and effluent supply continues, the aforementioned vegetation will colonize the pyrite trail and will eventually protect QENP and Lake George from metal contamination.

Osaliya, R.; Kansiime, F.; Oryem-Origa, H.; Kateyo, E.

212

Testing wetland features to increase amphibian reproductive success and species richness for mitigation and restoration.  

PubMed

Aquatic habitat features can directly influence the abundance, species richness, and quality of juvenile amphibians recruited into adult populations. We examined the influences of within-wetland slope, vegetation, and stocked mosquito fish (Gambusia affinis) on amphibian metamorph production and species richness during the first two years post-construction at 18 experimental wetlands in northeast Missouri (U.S.A.) grasslands. We used an information theoretic approach (AICc) to rank regression models representing total amphibian metamorph production, individual amphibian species metamorph production, and larval amphibian species richness. Total amphibian metamorph production was greatest at shallow-sloped, fish-free wetlands during the first year, but shallow-sloped wetlands with high vegetation cover were best the second year. Species richness was negatively associated with fish and positively associated with vegetation in both survey years. Leopard frog (Rana blairi/sphenocephala complex) metamorph quality, based on average metamorph size, was influenced by slope and the number of cohorts in the wetland. However, the tested variables had little influence on the size of American toads (Bufo americanus) or boreal chorus frogs (Pseudacris maculata). Our results indicate that wetlands designed to act as functional reproductive habitat for amphibians should incorporate shallows, high amounts of planted or naturally established vegetation cover, and should be fish-free. PMID:22908722

Shulse, Christopher D; Semlitsch, Raymond D; Trauth, Kathleen M; Gardner, James E

2012-07-01

213

Spectrum characteristic interpretation of wetland vegetation based on detrended canonical correspondence analysis ordination in Wild Duck Lake  

Microsoft Academic Search

Relating the characteristics of vegetation surface features to patterns of reflectance is a vital stage in the interpretation of remotely sensed imagery. This study applied the survey of communities, and the spectrum characteristic measuring, the detrended canonical correspondence analysis (DCCA) to analyze the relationships of community types and its spectrum characteristic in Wild Duck Lake,China. The results are as follows:

Xiao-yu Guo; Wen-ji Zhao; Ke Liu; Juan Long

2010-01-01

214

The Virginia Wetlands Report  

E-print Network

and 54,600 acres of inland wetlands lost in the Chesapeake Bay watershed. Annual Chesapeake Bay region management strategy. The 1987 Chesapeake Bay Agreement, which established a Chesa- peake Bay Wetlands Policy was designed to reduce point source pollution in waters under federal jurisdiction. Sec- tion 404 of the CWA

215

Avian utilization of subsidence wetlands  

SciTech Connect

Diverse and productive wetlands have resulted from coal mining in the midwest. The trend from surface to underground mining has increased the potential for subsidence. Planned subsidence of longwall mining areas provides increased opportunities for wetland habitat establishment. Planned subsidence over a 180 meter (590 foot) deep longwall mine in southern Illinois during 1984 to 1986 produced three subsidence wetlands totaling 15 hectares (38 acres). The resulting palustrine emergent wetlands enhanced habitat diversity within the surrounding palustrine forested unsubsided area. Habitat assessments and evaluations of avian utilization of the subsidence wetlands were conducted during February 1990 through October 1991. Avian utilization was greatest within the subsided wetlands. Fifty-three bird species representing seven foraging guilds utilized the subsidence wetlands. Wading/fishing, dabbling waterfowl, and insectivorous avian guilds dominated the subsidence wetlands. The subsidence wetlands represented ideal habitat for wood ducks and great blue herons which utilized snags adjacent to and within the wetlands for nesting (19 great blue heron nests produced 25 young). Dense cover and a rich supply of macroinvertebrates provide excellent brood habitat for wood ducks, while herpetofauna and ichthyofauna provided abundant forage in shallow water zones for great blue herons and other wetland wading birds. The diversity of game and non-game avifauna utilizing the subsidence areas demonstrated the unique value of these wetlands. Preplanned subsidence wetlands can help mitigate loss of wetland habitats in the midwest.

Nawrot, J.R.; Conley, P.S.; Smout, C.L. [Southern Illinois Univ., Carbondale, IL (United States)

1995-09-01

216

The biogeochemistry of nitrogen in freshwater wetlands  

Microsoft Academic Search

The biogeochemistry of N in freshwater wetlands is complicated by vegetation characteristics that range from annual herbs to perennial woodlands; by hydrologic characteristics that range from closed, precipitation-driven to tidal, riverine wetlands; and by the diversity of the nitrogen cycle itself. It is clear that sediments are the single largest pool of nitrogen in wetland ecosystems (100's to 1000's g

William B. Bowden

1987-01-01

217

Reed wetland extraction in the Yellow River Delta Nature Reserve based on knowledge inference technology  

NASA Astrophysics Data System (ADS)

With the reduction of sediments into the sea, the area of reed wetland, which is the key habitat of red-crowned crane, has been shrinking in the Yellow River Delta Nature Reserve, China. With Landsat Thematic Mapper (TM) images and field observations, we mapped the reed wetland using the knowledge inference technology. Six wetland types were extracted using a supervised classification method. To resolve the confusions between reeds and other wetland types, a set of rules were established. Firstly, reed wetland was separated from mudflat wetland, rearing and shrimp pond and water body by using the normalized digital vegetation index (NDVI). Secondly, reed wetland was distinguished from paddy field by using image texture information. Thirdly, the reed wetland was separated from the Chinese tamarisk by using the principal transformation. All these rules were built by using ERDAS Imagine's knowledge engineer. Reed wetland classification was conducted by using the neighbor analysis technology. The accuracy assessment shows that the knowledge-based classification obtained an overall accuracy of 89.02% and kappa coefficient of 0.89, which was better than the traditional supervised classification.

Fu, Xiaomin; Wang, Hong; Li, Ling

2009-06-01

218

Assessment of acreage and vegetation change in Florida`s Big Bend tidal wetlands using satellite imagery  

SciTech Connect

Fluctuations in sea level and impending development on the west coast of Florida have aroused concern for the relatively pristine tidal marshes of the Big Bend. Landsat Thematic Mapper (TM) images for 1986 and 1995 are processed and evaluated for signs of change. The images cover 250 km of Florida`s Big Bend Gulf Coast, encompassing 160,000 acres of tidal marshes. Change is detected using the normalized difference vegetation index (NDVI) and land cover classification. The imagery shows negligible net loss or gain in the marsh over the 9-year period. However, regional changes in biomass are apparent and are due to natural disturbances such as low winter temperatures, fire, storm surge, and the conversion of forest to marsh. Within the marsh, the most prominent changes in NDVI and in land cover result from the recovery of mangroves from freezes, a decline of transitional upland vegetation, and susceptibility of the marsh edge and interior to variations in tidal flooding.

Raabe, E.A.; Stumpf, R.P. [Geological Survey, St. Petersburg, FL (United States)

1997-06-01

219

Plant-water regime management in a wetland: consequences for a floating vegetation-nesting bird, whiskered tern Chlidonias hybridus  

Microsoft Academic Search

In this study we investigated the interplay between water level management, floating macrophytic vegetation and nesting whiskered\\u000a tern (Chlidonias hybridus) during 8 years (1995–2002) at a shallow macrophyte-dominated lake in western France. The specific question was to see if\\u000a slight increases in the water regime of the lake (three scenarios), as part of a restoration programme, affect the timing\\u000a of

Jean-Marc Paillisson; Sebastien Reeber; Alexandre Carpentier; Loic Marion

2006-01-01

220

Plant-water regime management in a wetland: consequences for a floating vegetation-nesting bird, whiskered tern Chlidonias hybridus  

Microsoft Academic Search

In this study we investigated the interplay between water level management, floating macrophytic vegetation and nesting whiskered\\u000a tern (Chlidonias hybridus) during 8 years (1995–2002) at a shallow macrophyte-dominated lake in western France. The specific question was to see if\\u000a slight increases in the water regime of the lake (three scenarios), as part of a restoration programme, affect the timing\\u000a of

Jean-Marc Paillisson; Sebastien Reeber; Alexandre Carpentier; Loic Marion

221

Wetland Visualizations  

NSDL National Science Digital Library

Compiled by Suzanne Savanick at SERC. Find wetland images and visualizations that illustrate wetland loss or wetland function. Browse the complete set of Visualization Collections. National Estuary Program Habitat ...

222

Assessment of Vegetation Establishment on Tailings Dam at an Iron Ore Mining Site of Suburban Beijing, China, 7 Years After Reclamation with Contrasting Site Treatment Methods  

NASA Astrophysics Data System (ADS)

Strip-mining operations greatly disturb soil, vegetation and landscape elements, causing many ecological and environmental problems. Establishment of vegetation is a critical step in achieving the goal of ecosystem restoration in mining areas. At the Shouyun Iron Ore Mine in suburban Beijing, China, we investigated selective vegetation and soil traits on a tailings dam 7 years after site treatments with three contrasting approaches: (1) soil covering (designated as SC), (2) application of a straw mat, known as "vegetation carpet", which contains prescribed plant seed mix and water retaining agent (designated as VC), on top of sand piles, and (3) combination of soil covering and application of vegetation carpet (designated as SC+VC). We found that after 7 years of reclamation, the SC+VC site had twice the number of plant species and greater biomass than the SC and VC sites, and that the VC site had a comparable plant abundance with the SC+VC site but much less biodiversity and plant coverage. The VC site did not differ with the SC site in the vegetation traits, albeit low soil fertility. It is suggested that application of vegetation carpet can be an alternative to introduction of topsoil for treatment of tailings dam with fine-structured substrate of ore sands. However, combination of topsoil treatment and application of vegetation carpet greatly increases vegetation coverage and plant biodiversity, and is therefore a much better approach for assisting vegetation establishment on the tailings dam of strip-mining operations. While application of vegetation carpet helps to stabilize the loose surface of fine-structured mine wastes and to introduce seed bank, introduction of fertile soil is necessary for supplying nutrients to plant growth in the efforts of ecosystem restoration of mining areas.

Yan, Demin; Zhao, Fangying; Sun, Osbert Jianxin

2013-09-01

223

An integrated approach to assess broad-scale condition of coastal wetlands--the Gulf of Mexico Coastal Wetlands pilot survey.  

PubMed

The Environmental Protection Agency (EPA) and U.S. Geological Survey (USGS) initiated a two-year regional pilot survey in 2007 to develop, test, and validate tools and approaches to assess the condition of northern Gulf of Mexico (GOM) coastal wetlands. Sampling sites were selected from estuarine and palustrine wetland areas with herbaceous, forested, and shrub/scrub habitats delineated by the US Fish and Wildlife Service National Wetlands Inventory Status and Trends (NWI S&T) program and contained within northern GOM coastal watersheds. A multi-level, stepwise, iterative survey approach is being applied to multiple wetland classes at 100 probabilistically-selected coastal wetlands sites. Tier 1 provides information at the landscape scale about habitat inventory, land use, and environmental stressors associated with the watershed in which each wetland site is located. Tier 2, a rapid assessment conducted through a combination of office and field work, is based on best professional judgment and on-site evidence. Tier 3, an intensive site assessment, involves on-site collection of vegetation, water, and sediment samples to establish an integrated understanding of current wetland condition and validate methods and findings from Tiers 1 and 2. The results from this survey, along with other similar regional pilots from the Mid-Atlantic, West Coast, and Great Lakes Regions will contribute to a design and implementation approach for the National Wetlands Condition Assessment to be conducted by EPA's Office of Water in 2011. PMID:19037735

Nestlerode, Janet A; Engle, Virginia D; Bourgeois, Pete; Heitmuller, Paul T; Macauley, John M; Allen, Yvonne C

2009-03-01

224

Wetland Types  

NSDL National Science Digital Library

This resource will help students to distinguish between wetland types. They will discover that coastal wetlands include salt marshes and tidal brackish marshes while inland wetlands consist of freshwater marshes, wet meadows, forested swamps, shrub swamps, bogs, fens, and vernal pools. A Guide to Wetland Wildlife in New England Regional Wetland "Celebrities" is included. This site is part of a guide that aims to help students get to know the complexities of wetlands, discover wildlife, enjoy the experience of being outdoors, and learn how necessary wetlands are to the health of our environment. Even though the site is about wetlands in New England for educators and their middle school students it suggests ways to study wetland characteristics, why wetlands are important, and how students and teachers can help protect a local wetland. An associated set of activities is also available.

225

Mitigation bank promotes research on restoring Coastal Plain depression wetlands (South Carolina).  

SciTech Connect

Barton, Christopher, D., Diane DeSteven and John C. Kilgo. 2004. Mitigation bank promotes research on restoring Coastal Plain depression wetlands (South Carolina). Ecol. Rest. 22(4):291-292. Abstract: Carolina bays and smaller depression wetlands support diverse plant communities and provide critical habitat for semi-aquatic fauna throughout the Coastal Plain region of the southeastern United States. Historically, many depression wetlands were altered or destroyed by surface ditching, drainage, and agricultural or silviculture uses. These important habitats are now at further risk of alteration and loss following a U.S. Supreme Court decision in 2001 restricting federal regulation of isolated wetlands. Thus, there is increased attention towards protecting intact sites and developing methods to restore others. The U.S. Department of Energy's (DOE) 312-mi2 (800-km2) Savannah River Site (SRS) in west-central South Carolina includes about 350 Carolina bays and bay-like wetland depressions, of which about two-thirds were degraded or destroyed prior to federal acquisition of the land. Although some of the altered wetlands have recovered naturally, others still have active active drainage ditches and contain successional forests typical of drained sites. In 1997, DOE established a wetland mitigation bank to compensate for unavoidable wetland impacts on the SRS. This effort provided an opportunity fir a systematic research program to investigate wetland restoration techniques and ecological responses. Consequently, research and management staffs from the USDA Forest Service, Westinghouse Savannah River Corporation, the Savannah River Technology Center, the Savannah River Ecology Laboratory (SREL) and several universities developed a collaborative project to restore degraded depression wetlands on the SRS. The mitigation project seeks cost-effective methods to restore the hydrology and vegetation typical of natural depression wetlands, and so enhance habitats for wetland-dependent wildlife. We present a brief summary of this project and the research studies now underway.

Barton, Christopher D.; DeSteven, Diane; Kilgo, John C.

2004-12-31

226

Spatio-Temporal Variation in Contrasting Effects of Resident Vegetation on Establishment, Growth and Reproduction of Dry Grassland Plants: Implications for Seed Addition Experiments  

PubMed Central

Successful establishment of plants is limited by both biotic and abiotic conditions and their interactions. Seedling establishment is also used as a direct measure of habitat suitability, but transient changes in vegetation might provide windows of opportunity allowing plant species to colonize sites which otherwise appear unsuitable. We aimed to study spatio-temporal variability in the effects of resident vegetation on establishment, growth and reproduction of dry grassland species in abandoned arable fields representing potentially suitable habitats. Seeds were sown in disturbed (bare of vegetation and roots) and undisturbed plots in three fields abandoned in the last 20 years. To assess the effects of temporal variation on plant establishment, we initiated our experiments in two years (2007 and 2008). Seventeen out of the 35 sown species flowered within two years after sowing, while three species completely failed to become established. The vegetation in the undisturbed plots facilitated seedling establishment only in the year with low spring precipitation, and the effect did not hold for all species. In contrast, growth and flowering rate were consistently much greater in the disturbed plots, but the effect size differed between the fields and years of sowing. We show that colonization is more successful when site opening by disturbance coincide with other suitable conditions such as weather or soil characteristics. Seasonal variability involved in our study emphasizes the necessity of temporal replication of sowing experiments. Studies assessing habitat suitability by seed sowing should either involve both vegetation removal treatments and untreated plots or follow the gradient of vegetation cover. We strongly recommend following the numbers of established individuals, their sizes and reproductive success when assessing habitat suitability by seed sowing since one can gain completely different results in different phases of plant life cycle. PMID:23755288

Knappová, Jana; Knapp, Michal; Münzbergová, Zuzana

2013-01-01

227

Assessing coastal plain wetland composition using advanced spaceborne thermal emission and reflection radiometer imagery  

NASA Astrophysics Data System (ADS)

Establishing wetland gains and losses, delineating wetland boundaries, and determining their vegetative composition are major challenges that can be improved through remote sensing studies. We used the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) to separate wetlands from uplands in a study of 870 locations on the Virginia Coastal Plain. We used the first five bands from each of two ASTER scenes (6 March 2005 and 16 October 2005), covering the visible to the short-wave infrared region (0.52-2.185mum). We included GIS data layers for soil survey, topography, and presence or absence of water in a logistic regression model that predicted the location of over 78% of the wetlands. While this was slightly less accurate (78% vs. 86%) than current National Wetland Inventory (NWI) aerial photo interpretation procedures of locating wetlands, satellite imagery analysis holds great promise for speeding wetland mapping, lowering costs, and improving update frequency. To estimate wetland vegetation composition classes, we generated a classification and regression tree (CART) model and a multinomial logistic regression (logit) model, and compared their accuracy in separating woody wetlands, emergent wetlands and open water. The overall accuracy of the CART model was 73.3%, while for the logit model was 76.7%. The CART producer's accuracy of the emergent wetlands was higher than the accuracy from the multinomial logit (57.1% vs. 40.7%). However, we obtained the opposite result for the woody wetland category (68.7% vs. 52.6%). A McNemar test between the two models and NWI maps showed that their accuracies were not statistically different. We conducted a subpixel analysis of the ASTER images to estimate canopy cover of forested wetlands. We used top-of-atmosphere reflectance from the visible and near infrared bands, Delta Normalized Difference Vegetation Index, and a tasseled cap brightness, greenness, and wetness in linear regression model with canopy cover as the dependent variable. The model achieved an adjusted-R 2 of 0.69 (RMSE = 2.7%) for canopy cover less than 16%, and an adjusted-R 2 of 0.04 (RMSE = 19.8%) for higher canopy cover values. Taken together, these findings suggest that satellite remote sensing, in concert with other spatial data, has strong potential for mapping both wetland presence and type.

Pantaleoni, Eva

228

Colonization of Restored Wetlands by Amphibians in Minnesota  

Microsoft Academic Search

Twelve wetlands (7 recently restored; 5 reference) in central and southern Minnesota were monitored during the 1998 breeding season to assess colonization of recently restored wetlands by amphibians, compare the amphibian fauna to that of reference wetlands and identify important factors influencing the probability of colonization. Eight amphibian species rapidly colonized recently restored wetlands and established breeding populations. Reference wetlands

RICHARD M. LEHTINEN; SUSAN M. GALATOWITSCH

2001-01-01

229

Wetland Science  

NSDL National Science Digital Library

This is the first section of a module about wetlands in New England for educators and their middle school students. Although designed for students in New England, it applies to and gives examples of wetlands across the country. It suggests ways to study wetland characteristics, why wetlands are important, and how students and teachers can help protect a local wetland. This guide aims to help students get to know the complexities of wetlands, discover wildlife, enjoy the experience of being outdoors, and learn how necessary wetlands are to the health of our environment. This first section explains what wetlands are and explains that the water cycle is the connection between wetlands and watersheds. In addition, it explains in detail the characteristics of wetland water, soil and plants. An associated set of activities is also available.

230

Evaluation of sampling methods for macroinvertebrate biodiversity estimation in heavily vegetated ponds  

Microsoft Academic Search

This article presents an evaluation of two sampling methods for assessing the biodiversity of heavily vegetated wetlands.\\u000a The aim was to establish an effective sampling regime to maximise total taxon richness and minimise sampling effort. Three\\u000a Integrated Constructed Wetland (ICW) systems in Annetown Valley, Co. Waterford, SE of the Republic of Ireland, were sampled\\u000a during spring and summer 2005. The

G. Becerra Jurado; M. Masterson; R. Harrington; M. Kelly-Quinn

2008-01-01

231

Vegetation patterns in a calcareous sloping fen of southwestern Massachusetts, USA  

Microsoft Academic Search

Calcareous sloping fens are minerotrophic wetland systems that are well known for their high species richness, but little\\u000a is known about the local processes that govern the spatial patterns of species distribution within these communities. This\\u000a study was undertaken to document vegetative patterns and to quantify community differences within one such calcareous wetland.\\u000a A 250-m transect was established along a

Deborah J. Picking; Peter L. M. Veneman

2004-01-01

232

HYDROMORPHIC DETERMINANTS OF AQUATIC HABITAT VARIABILITY IN LAKE SUPERIOR COASTAL WETLANDS  

EPA Science Inventory

This manuscript evaluates patterns in water quality, water movement, substrate, and vegetation in 10 Lake Superior coastal wetlands in light of wetland hydrology and morphology. Water quality, substrate, and vegetation structure are important aspects of habitat for fishes that u...

233

Integration of multi-temporal spectral and structural information to map wetland vegetation in a brackish Connecticut marsh  

NASA Astrophysics Data System (ADS)

This study utilizes multitemporal QuickBird and single date LiDar canopy height data to classify the common plant communities of a tidal marsh at the mouth of the Connecticut River. A specific goal was to map the expanding distribution of non-native Phragmites australis (Cav.) Trin ex Steud (common reed), which has been outcompeting native species, particularly in disturbed marshes. P. australis spreads vigorously, forming dense monocultures that result in reduced biodiversity of plant, avian and macroinvertebrate species. We collected visible to near-infrared (VNIR) reflectance spectra of the dominant plant species S. patens (salt meadow grass), Typha spp. (cattail), and P. australis over two growing seasons to develop metrics that maximize phenological spectral and canopy height variability to distinguish these plants within a complex marsh community containing >100 plant species. Relative to other species, P. australis is best distinguished by its high NIR response and height late in the growing season. Typha spp. was well distinguished from other species by its high red/green ratio and S. patens by a unique green/blue ratio and low heights throughout the growing season. The field spectra and LiDar-derived heights were used to guide an object-oriented classification methodology using multitemporal QuickBird data collected over the same time interval as the field spectra. The classification was validated using a field inventory of marsh vegetation. Overall maximum fuzzy accuracy for the classification was 97% for Phragmites, 63% for Typha spp. and 80% for S. patens meadows; this improved to 97%, 76%, and 92%, respectively, using a fuzzy acceptable match measure. Image acquisition timing was critical for the identification of targeted plant species in this heterogeneous marsh. These datasets and protocols may provide coastal resource managers, municipal officials and researchers a set of recommended guidelines for remote sensing data collection for marsh inventory and monitoring.

Gilmore, M. S.; Wilson, E. H.; Barrett, N.; Civco, D. L.; Prisloe, S.; Hurd, J. D.; Chadwick, C.

2008-12-01

234

Wetlands stewardship  

SciTech Connect

Wetlands have important ecological values and functions. It is estimated that 80 percent of the Nation's coastal fisheries are dependent on wetlands for spawning, nursery areas, and food sources. Both coastal and inland wetlands provide essential breeding, nesting, feeding, and predator escape habitats for millions of waterfowl, other birds, mammals, and reptiles. Well over one-third of the 564 plant and animal species listed as threatened or endangered in the United States utilize wetland habitats during some portion of their life cycle. Wetlands Stewardship is intended as a resource for everyone interested in wetlands protection.

Whelan, J.M.

1992-04-01

235

Chemical Properties of Pore Water and Sediment at Three Wetland Sites Near the F- and H-Area Seepage Basins, Savannah River Site  

SciTech Connect

In 1980, vegetative stress and arboreal mortality in wetland plant communities down-gradient from the F- and H-Area seepage basins were detected using aerial imagery. By 1988, approximately six acres in H-Area and four acres in F-Area had been adversely impacted. Today, wetland plant communities have become well established at the H-Area tree-kill zone.

Friday, G.P.

2001-05-15

236

[Wetland landscape ecological classification: research progress].  

PubMed

Wetland landscape ecological classification, as a basis for the studies of wetland landscape ecology, directly affects the precision and effectiveness of wetland-related research. Based on the history, current status, and latest progress in the studies on the theories, indicators, and methods of wetland landscape classification, some scientific wetland classification systems, e.g., NWI, Ramsar, and HGM, were introduced and discussed in this paper. It was suggested that a comprehensive classification method based on HGM and on the integral consideration of wetlands spatial structure, ecological function, ecological process, topography, soil, vegetation, hydrology, and human disturbance intensity should be the major future direction in this research field. Furthermore, the integration of 3S technologies, quantitative mathematics, landscape modeling, knowledge engineering, and artificial intelligence to enhance the automatization and precision of wetland landscape ecological classification would be the key issues and difficult topics in the studies of wetland landscape ecological classification. PMID:20353081

Cao, Yu; Mo, Li-jiang; Li, Yan; Zhang, Wen-mei

2009-12-01

237

[Wetland ecosystems formation and its protection in Yellow River Delta].  

PubMed

Site investigation, satellite photo analysis and historic material analysis show that the vast neonatal wetlands in Yellow River Delta were created by high concentration sediment of the river and the land-sea evolution. Affected by the regional climate, landform, geological deposition, soil, vegetation and their interactions, the wetlands covered 4.5 x 10(5) hm2, 6.84 x 10(4) hm2 of which were artificial wetlands. The wetland ecosystems changed with the waving of the Yellow River Mouth and the land development in the Delta area. From ocean to land, the sublittoral aquatic wetland, eulittoral wetland, eplittoral salt wetland, bulrush-quitch wetland, meadow wetland and land agroecosystem were developed. The wetland ecosystems had abundant biological resources, including 1524 wild animals, 300 birds and 1040 fishes, which were changed recently by the oil development and affected by the interruption of Yellow River. Wetland protection should be strengthened in resources utilization. PMID:11766568

Mu, C; Yang, L; Wang, J; Hu, Y; Lin, H

2000-02-01

238

Wetland InSAR  

NASA Astrophysics Data System (ADS)

Wetlands are transition zones where the flow of water, the nutrient cycling, and the sun energy meet to produce a unique and very productive ecosystem. They provide critical habitat for a wide variety of plant and animal species, including the larval stages of many ocean fish. Wetlands also have a valuable economical importance, as they filter nutrients and pollutants from fresh water used by human and provide aquatic habitats for outdoor recreation, tourism, and fishing. Globally, many such regions are under severe environmental stress, mainly from urban development, pollution, and rising sea level. However, there is increasing recognition of the importance of these habitats, and mitigation and restoration activities have begun in a few regions. A key element in wetlands conservation, management, and restoration involves monitoring its hydrologic system, as the entire ecosystem depends on its water supply. Heretofore, hydrologic monitoring of wetlands are conducted by stage (water level) stations, which provide good temporal resolution, but suffer from poor spatial resolution, as stage station are typically distributed several, or even tens of kilometers, from one another. Wetland application of InSAR provides the needed high spatial resolution hydrological observations, complementing the high temporal resolution terrestrial observations. Although conventional wisdom suggests that interferometry does not work in vegetated areas, several studies have shown that both L- and C-band interferograms with short acquisition intervals (1-105 days) can maintain excellent coherence over wetlands. In this study we explore the usage of InSAR for detecting water level changes in various wetland environments around the world, including the Everglades (south Florida), Louisiana Coast (southern US), Chesapeake Bay (eastern US), Pantanal (Brazil), Okavango Delta (Botswana), and Lena Delta (Siberia). Our main study area is the Everglades wetland (south Florida), which is covered by probably the densest stage network in the world (more than 200 stations), located 5-10 km from one another. The stage data is very important in evaluating the uncertainty of the InSAR observations. Stage data also allow us to tie the relative InSAR observations (water level changes) to absolute reference frame and to produce high spatial-resolution (10-100 m resolution) maps of absolute water levels. High resolution wetland interferograms also provide direct observations of flow patterns and flow discontinuities and serve as excellent constraints for high resolution flow models. Because many wetlands are located in coastal zones, the high spatial resolution InSAR observations provide an opportunity to study dynamic interaction of tides and freshwater inflow, and the role of vegetation resistance to surface water flow.

Wdowinski, S.; Kim, S.; Amelung, F.; Dixon, T.

2006-12-01

239

Detached Wetlands  

NSDL National Science Digital Library

This video depicts a detached wetland, a small pool that forms beside a shallow meandering stream when it overflows its banks. These wetlands are important breeding grounds for the invertebrates that live in and beside streams

Ket

2011-01-11

240

Wetland Functions  

NSDL National Science Digital Library

This resource explains a number of critical functions performed by wetlands. Students will discover that wetlands moderate impacts from flooding, control erosion, purify water, and provide habitat for fish and wildlife. They also provide a unique natural environment for people to enjoy outdoor recreation activities. It is part of a module that aims to help students get to know the complexities of wetlands, discover wildlife, enjoy the experience of being outdoors, and learn how necessary wetlands are to the health of our environment. Although it is about wetlands in New England for educators and their middle school students, it suggests ways to study wetland characteristics, why wetlands are important, and how students and teachers can help protect a local wetland in any part of the country. An associated set of activities is also available.

241

Tidal Wetlands Impacts Data Homepage  

NSDL National Science Digital Library

A cooperative effort between the Virginia Institute of Marine Science (VIMS) and the US Environmental Protection Agency (EPA), this site was designed "to assist resource managers, academicians, students, politicians, and the general public in the areas of research, education, environmental management, and policy ... about human impacts on tidal wetlands in Virginia." Non-interactive sections include the Overview of the VIMS Program, describing data collection methods; Overview of Management, describing the history and current status of tidal wetlands management; Nontidal wetlands impacts information, summarizing impacts to nontidal wetlands; and General Data Summaries, offering display tables and graphs. Two searchable sections provide for select examination of the data: Design a query for 1993-1997 and Design a query for 1988-1992 enable viewers to examine data by year, activity category, and watershed. Results are presented in tabular form and "display impacts to vegetated and nonvegetated wetlands by square footage." Photographs accompany the summary data.

242

Wetland Mitigation Monitoring at the Fernald Preserve - 13200  

SciTech Connect

The U.S. Department of Energy is responsible for 7.2 hectares (17.8 acres) of mitigation wetland at the Fernald Preserve, Ohio. Remedial activities affected the wetlands, and mitigation plans were incorporated into site-wide ecological restoration planning. In 2008, the Fernald Natural Resource Trustees developed a comprehensive wetland mitigation monitoring approach to evaluate whether compensatory mitigation requirements have been met. The Fernald Preserve Wetland Mitigation Monitoring Plan provided a guideline for wetland evaluations. The Ohio Environmental Protection Agency (Ohio EPA) wetland mitigation monitoring protocols were adopted as the means for compensatory wetland evaluation. Design, hydrologic regime, vegetation, wildlife, and biogeochemistry were evaluated from 2009 to 2011. Evaluations showed mixed results when compared to the Ohio EPA performance standards. Results of vegetation monitoring varied, with the best results occurring in wetlands adjacent to forested areas. Amphibians, particularly ambystomatid salamanders, were observed in two areas adjacent to forested areas. Not all wetlands met vegetation performance standards and amphibian biodiversity metrics. However, Fernald mitigation wetlands showed substantially higher ratings compared to other mitigated wetlands in Ohio. Also, soil sampling results remain consistent with other Ohio mitigated wetlands. The performance standards are not intended to be 'pass/fail' criteria; rather, they are reference points for use in making decisions regarding future monitoring and maintenance. The Trustees approved the Fernald Preserve Wetland Mitigation Monitoring Report with the provision that long-term monitoring of the wetlands continues at the Fernald Preserve. (authors)

Powell, Jane [Fernald Preserve Site Manager, DOE Office of Legacy Management, Harrison, Ohio (United States)] [Fernald Preserve Site Manager, DOE Office of Legacy Management, Harrison, Ohio (United States); Bien, Stephanie; Decker, Ashlee; Homer, John [Environmental Scientist, S.M. Stoller Corporation, Harrison, Ohio (United States)] [Environmental Scientist, S.M. Stoller Corporation, Harrison, Ohio (United States); Wulker, Brian [Intern, S.M. Stoller Corporation, Harrison, Ohio (United States)] [Intern, S.M. Stoller Corporation, Harrison, Ohio (United States)

2013-07-01

243

Spatial organization and ecohydrological interactions in oxygen-limited vegetation ecosystems  

NASA Astrophysics Data System (ADS)

Wetlands are characterized by extremely high biodiversity and primary productivity (comparable to tropical rain forests), provide critical habitats for rare and endangered vegetation and animal species, and mediate the effects of floods and the action of the sea on the coast. A deep understanding of wetland system functioning cannot be acquired by simply reducing its dynamics to a collection of parts but requires the explicit description of wetland physical and ecological processes as fully interacting components. In fact, the complex spatial ecohydrological patterns characterizing wetland areas arise as a result of the coupled evolution of their ecological, hydrological, and morphological features. Here we examine observations of prominent spatial patterns in wetland vegetation and link them to the relevant hydrological and ecological processes. We describe the limitations to vegetation development due to scarce soil oxygen availability and implement a mathematical model, based on Richards' equation, coupling subsurface water flow and plant water uptake in a tidal salt marsh. The soil aeration patterns arising from such interactions highlight the central role of vegetation in increasing soil aeration, possibly inducing the establishment of a permanently aerated soil layer (in spite of tidal flooding), and the influence of different soil characteristics on soil oxygen availability. Finally, we discuss how ecohydrological interactions can contribute to explain patterns of vegetation colonization and spatial heterogeneity.

Marani, Marco; Silvestri, Sonia; Belluco, Enrica; Ursino, Nadia; Comerlati, Andrea; Tosatto, Omar; Putti, Mario

2006-06-01

244

Climate change and intertidal wetlands.  

PubMed

Intertidal wetlands are recognised for the provision of a range of valued ecosystem services. The two major categories of intertidal wetlands discussed in this contribution are saltmarshes and mangrove forests. Intertidal wetlands are under threat from a range of anthropogenic causes, some site-specific, others acting globally. Globally acting factors include climate change and its driving cause-the increasing atmospheric concentrations of greenhouse gases. One direct consequence of climate change will be global sea level rise due to thermal expansion of the oceans, and, in the longer term, the melting of ice caps and glaciers. The relative sea level rise experienced at any one locality will be affected by a range of factors, as will the response of intertidal wetlands to the change in sea level. If relative sea level is rising and sedimentation within intertidal wetlands does not keep pace, then there will be loss of intertidal wetlands from the seaward edge, with survival of the ecosystems only possible if they can retreat inland. When retreat is not possible, the wetland area will decline in response to the "squeeze" experienced. Any changes to intertidal wetland vegetation, as a consequence of climate change, will have flow on effects to biota, while changes to biota will affect intertidal vegetation. Wetland biota may respond to climate change by shifting in distribution and abundance landward, evolving or becoming extinct. In addition, impacts from ocean acidification and warming are predicted to affect the fertilisation, larval development, growth and survival of intertidal wetland biota including macroinvertebrates, such as molluscs and crabs, and vertebrates such as fish and potentially birds. The capacity of organisms to move and adapt will depend on their life history characteristics, phenotypic plasticity, genetic variability, inheritability of adaptive characteristics, and the predicted rates of environmental change. PMID:24832670

Ross, Pauline M; Adam, Paul

2013-01-01

245

Climatic and physiographic controls on wetland type and distribution in Manitoba, Canada  

Microsoft Academic Search

Wetlands represent a substantial part of Manitoba’s terrestrial landscape, covering 233,340 km2 or 43% of the province; peatlands represent 90% of all wetlands. A wetland inventory for Manitoba is presented following\\u000a a classification scheme grounded in wetland function, vegetation, and landform. The province is subdivided into twelve wetland\\u000a regions each having distinctive wetland types and abundances. A hybrid Detrended Canonical

Linda Halsey; Dale Vitt; Stephen Zoltai

1997-01-01

246

Maine Department of Conservation: Wetlands Activity  

NSDL National Science Digital Library

This four-week unit contains activities in which students investigate the natural history of a wetland, identify its boundaries, and study how it functions in the environment. They will investigate the formation of wetlands in Maine; prepare a series of map overlays researching wetland conditions for a site they have chosen in the community; learn how to recognize a wetland by hydrology, vegetation, and soil type; inventory the functions of the wetland site; and write an evaluation for it. To conclude the unit, the students will hold a mock town meeting in which they discuss the views of the various interested parties in preserving or destroying the wetland and debate the merits of the proposed changes to federal wetlands regulations.

2005-10-06

247

Control of hardwood regeneration in restored carolina bay depression wetlands.  

SciTech Connect

Carolina bays are depression wetlands located in the coastal plain region of the eastern United States. Disturbance of this wetland type has been widespread, and many sites contain one or more drainage ditches. Restoration of bays is of interest because they are important habitats for rare flora and fauna. Previous bay restoration projects have identified flood-tolerant woody competitors in the seedbank and re-sprouting as impediments to the establishment of desired herbaceous wetland vegetation communities. We restored 3 bays on the Savannah River Site, South Carolina, by plugging drainage ditches, harvesting residual pine/hardwood stands within the bays, and monitoring the vegetative response of the seedbank to the hydrologic change. We applied a foliar herbicide on one-half of each bay to control red maple (Acerrubrum), sweetgum (Liquidambar styraciflua), and water oak (Quercus nigra) sprouting, and we tested its effectiveness across a hydrologic gradient in each bay. Hardwood regeneration was partially controlled by flooding in bays that exhibited long growing season hydroperiods. The findings also indicated that herbicide application was an effective means for managing hardwood regeneration and re-sprouting in areas where hydrologic control was ineffective. Herbicide use had no effect on species richness in the emerging vegetation community. In late-season drawdown periods, or in bays where hydroperiods are short, more than one herbicide application may be necessary.

Moser, Lee, J.; Barton, Christopher, D.; Blake, John, I.

2012-06-01

248

Methane Fluxes from Subtropical Wetlands  

NASA Astrophysics Data System (ADS)

It is well documented that green house gas concentrations have risen at unequivocal rates since the industrial revolution but the disparity between anthropogenic sources and natural sources is uncertain. Wetlands are one example of a natural ecosystem that can be a substantial source or sink for methane (CH4) depending on climate conditions. Due to strict anaerobic conditions required for CH4-generating microorganisms, natural wetlands are one of the main sources for biogenic CH4. Although wetlands occupy less than 5% of total land surface area, they contribute approximately 20% of total CH4 emissions to the atmosphere. The processes regulating CH4 emissions are sensitive to land use and management practices of areas surrounding wetlands. Variation in adjacent vegetation or grazing intensity by livestock can, for example, alter CH4 fluxes from wetland soils by altering nutrient balance, carbon inputs and hydrology. Therefore, understanding how these changes will affect wetland source strength is essential to understand the impact of wetland management practices on the global climate system. In this study we quantify wetland methane fluxes from subtropical wetlands on a working cattle ranch in central Florida near Okeechobee Lake (27o10'52.04'N, 81o21'8.56'W). To determine differences in CH4 fluxes associated with land use and management, a replicated (n = 4) full factorial experiment was designed for wetlands where the surrounding vegetation was (1) grazed or un-grazed and (2) composed of native vegetation or improved pasture. Net exchange of CH4 and CO2 between the land surface and the atmosphere were sampled with a LICOR Li-7700 open path CH4 analyzer and Li-7500A open path CO2/H20 analyzer mounted in a 1-m3 static gas-exchange chamber. Our results showed and verified that CH4 emissions from subtropical wetlands were larger when high soil moisture was coupled with high temperatures. The presence of cattle only amplified these results. These results help quantify GHG emissions from subtropical wetlands while demonstrating the differences in these fluxes based on the surrounding ecosystem.

DeLucia, N.; Gomez-Casanovas, N.; Bernacchi, C.

2013-12-01

249

Identification and characterization of wetlands in the Bear Creek watershed  

SciTech Connect

The primary objective of this study was to identify, characterize, and map the wetlands in the Bear Creek watershed. A preliminary wetland categorization system based on the Cowardin classification system (Cowardin et al. 1979) with additional site-specific topographic, vegetation, and disturbance characteristic modifiers was developed to characterize the type of wetlands that exist in the Bear Creek watershed. An additional objective was to detect possible relationships among site soils, hydrology, and the occurrence of wetlands in the watershed through a comparison of existing data with the field survey. Research needs are discussed in the context of wetland functions and values and regulatory requirements for wetland impact assessment and compensatory mitigation.

Rosensteel, B.A. [JAYCOR, Oak Ridge, TN (United States); Trettin, C.C. [Oak Ridge National Lab., TN (United States)

1993-10-01

250

Uptake of /sup 226/Ra by established vegetation and black cutworm larvae, Agrotis ipsilon (class Insecta: order Lepidoptera), on U mill tailings at Elliot Lake, Canada  

SciTech Connect

Radium-226 levels in samples from an inactive U tailings site at Elliot Lake, Ontario, Canada, were: 9140 +/- 500 mBq g-1 dry weight in the substrate; 62 +/- 1 mBq g-1 dry weight in rye, Secale cereale, and less than 3.7 mBq g-1 dry weight in oats, Avena sativa, the dominant species established by revegetation of the tailings; and 117 +/- 7 mBq g-1 dry weight in washed and unwashed black cutworm larvae. Concentration ratios were: vegetation to tailings 0.001-0.007; black cutworms to vegetation 3.6 and black cutworms to tailings 0.01. The values are considered too low to be considered a hazard to herring gulls, Larus argentatus, which occasionally feed on cutworms.

Clulow, F.V.; Dave, N.K.; Lim, T.P.; Cloutier, N.R.

1988-07-01

251

Wetland change detection in Nile swamps of southern Sudan using multitemporal satellite imagery  

NASA Astrophysics Data System (ADS)

In this study, the maximum likelihood supervised classification and the post-classification comparison change detection are applied in order to monitor the wetlands by assessing and quantifying the wetland cover changes in the Nile swamps of southern Sudan, called the Sudd, by using the ERDAS IMAGINE software. Three multispectral satellite imageries, acquired in the wet season from 1986 to 2006 by Landsat TM and Landsat ETM+ images, are classified into five main land cover classes namely water, vegetation, urban, wetland-vegetation, and wetland-no vegetation, by using the maximum likelihood supervised classification. A pixel-by-pixel comparison was then performed over the classified thematic map images. The post-classification change detection results show a 3.69% decrease in the wetland-vegetation areas and a 2.68% decrease in the wetland-no vegetation areas within the period 1986 to 1999. In addition, a noticeable increase is observed in the wetland-vegetation areas within the period 1999 to 2006 in the Sudd area as 14.95% of the land cover classes' areas, excluding the wetland-vegetation areas are changed into wetland-vegetation areas while there was a decrease of 5.18% in the wetland-no vegetation areas within the period 1999 to 2006. The objective of this paper is to introduce precedence in studying the wetland cover changes over the Sudd area which can help the output planners develop water resources management projects leading to enhance the life conditions in the Sudd region.

Soliman, Ghada; Soussa, Hoda

2011-01-01

252

Exploring Wetlands.  

ERIC Educational Resources Information Center

Presents a wetlands education model for secondary education students. Students monitor a wetland, participate in decision-making, and take actions to protect it. In a series of six steps, the model guides students through the process of defining a problem; envisioning solutions; evaluating appropriate solutions based on environmental, economic and…

Kerr, Elizabeth; Harrison, Gordon

1996-01-01

253

Freshwater Wetlands.  

ERIC Educational Resources Information Center

Provides descriptions about freshwater wetlands, such as marshes, swamps, and bogs. Contains three learning activities which deal with unusual wetland plants, the animals and plants in a typical marsh, and the effects of a draught on a swamp. Included are reproducible handouts and worksheets for two of the activities. (TW)

Naturescope, 1986

1986-01-01

254

Groundwater flow modelling of three wetland ecosystems in river valleys in Flanders, Belgium  

Microsoft Academic Search

Research in the ecology of wetlands is quite established. However, research in the hydrology of wetlands is much less developed. In Flanders, Belgium, a research project was initiated to investigate ecohydrological differences in wetlands. Three wetlands (Doode Bemde, Vors- donkbos, and Zwarte Beek Valley) have been examined in detail. As these wetlands are predominantly fed by discharging groundwater, the groundwater

T. Asefa; P. Van Rossum; F. De Smedt

255

Organic carbon oxidation and suppression of methane production by microbial Fe(III) oxide reduction in vegetated and unvegetated freshwater wetland sediments  

Microsoft Academic Search

High concentrations (20-75 pmol cm-3) of amorphous Fe(III) oxide were observed in unvegetated surface and Juncus eflusus rhizosphere sediments of a freshwater wetland in the southeastern United States. Incu- bation experiments demonstrated that microbial Fe(III) oxide reduction suppressed sulfate reduction and methanogenesis in surface scdimcnts and mediated 240% of depth-integrated (O-10 cm) unvegetated sedi- ment carbon metabolism, compared to I

Eric E. Roden; Robert G. Wetzel

1996-01-01

256

ERTS-1 investigation of wetlands ecology  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. Data from aircraft can be used for large scale mapping where detailed information is necessary, whereas Landsat-1 data are useful for rapid mapping of gross wetland boundaries and vegetative composition and assessment of seasonal change plant community composition such as high and low growth forms of Spartina alterniflora, Juncus roemarianus, and Spartina cynosuroides. Spoil disposal and wetland ditching activities may also be defined. Wetland interpretation is affected by tidal stage; drainage patterns are more easily detected at periods of low water. Species discrimination is easier at periods of high water during the growing season; upper wetland boundaries in fresh water tidal marshes are more easily delineated during the winter months when marsh vegetation is largely dead or dormant. Fresh water discharges from coastal streams may be inferred from the species composition of contiguous wetlands.

Anderson, R. R. (principal investigator); Carter, V.; Mcginness, J.

1975-01-01

257

Productivity of wet soils: Biomass of cultivated and natural vegetation  

SciTech Connect

Wet soils, soils which have agronomic limitations because of excess water, comprise 105 million acres of non-federal land in the conterminous United States. Wet soils which support hydrophytic plants are ''wetlands'', and are some of the most productive natural ecosystems in the world. When both above- and belowground productivity are considered, cattail (Typha latifolia) is the most productive temperate wetland species (26.4 Mg/ha/year). Both cattail and reed (Phragmites australis) have aboveground productivities of about 13 Mg/ha/year. Although average aboveground yields of reed canarygrass (Phalaris arundinacea) are lower (9.5 Mg/ha/year), techniques for its establishment and cultivation are well-developed. Other herbaceous wetland species which show promise as biomass crops include sedge (Carex spp.), river bulrush (Scirpus fluviatilis) and prairie cordgrass (Spartina pectinata). About 40% of wet soils in the conterminous US are currently cultivated, and they produce one-quarter of the major US crops. Most of this land is artificially drained for crops such as corn, soybeans, and vegetables. US wetlands are drained for agriculture at the rate of 223,000 ha/yr. Paddies flooded with water are used to grow rice, cranberries, and wild rice. Forage and live sphagnum moss are products of undrained wetlands. A number of federal and state regulations apply to the draining or irrigation of wetlands, but most do not seriously restrict their use for agriculture. 320 refs., 36 tabs.

Johnston, C.A.

1988-12-01

258

Hydrogeomorphic and Anthropogenic Influences on Water Quality, Habitat, and Fish of Great Lakes Coastal Wetlands  

EPA Science Inventory

Great Lakes coastal wetlands represent a dynamic interface between coastal watersheds and the open lake. Compared to the adjacent lakes, these wetlands have generally warmer water, reduced wave energy, shallow bathymetry, higher productivity, and structurally complex vegetated h...

259

7 CFR 12.33 - Use of wetland and converted wetland.  

...in this part, the production of an agricultural commodity on land determined by...not make possible the production of an agricultural commodity on these other wetlands...extent of woody vegetation, and the history of use. In accordance with §...

2014-01-01

260

Longitudinal dispersion in vegetated flow  

E-print Network

Vegetation is ubiquitous in rivers, estuaries and wetlands, strongly influencing both water conveyance and mass transport. The plant canopy affects both mean and turbulent flow structure, and thus both advection and ...

Murphy, Enda

2006-01-01

261

The impact of pumped water from a de-watered Magnesian limestone quarry on an adjacent wetland: Thrislington, County Durham, UK.  

PubMed

Although quarrying is often cited as a potential threat to wetland systems, there is a lack of relevant, quantitative case studies in the literature. The impact of pumped groundwater discharged from a quarry into a wetland area was assessed relative to reference conditions in an adjacent fen wetland that receives only natural runoff. Analysis of vegetation patterns at the quarry wetland site, using Detrended Correspondence Analysis and the species indicator values of Ellenberg, revealed a clear disparity between community transitions in the quarry wetland and the reference site. Limited establishment of moisture-sensitive taxa, the preferential proliferation of robust wetland species and an overall shift towards lower species diversity in the quarry wetland were explicable primarily by the physico-chemical environment created by quarry dewatering. This encompassed high pH (up to 12.8), sediment-rich effluent creating a nutrient-poor substrate with poor moisture retention in the quarry wetland, and large fluctuations in water levels. PMID:15993994

Mayes, W M; Large, A R G; Younger, P L

2005-12-01

262

Results of preliminary reconnaissance trip to determine the presence of wetlands in wet forest habitats on the Island of Hawaii as part of the Hawaii Geothermal Project, October 1993  

SciTech Connect

In October 1993, the authors sampled soils, vegetation, and hydrology at eight sites representing a range of substrates, elevations, soil types, and plant community types within rainforest habitats on the Island of Hawaii. Their purpose was to determine whether any of these habitats were wetlands according to the 1987 Corps of Engineers Wetlands Delineation Manual. None of the rainforest habitats they sampled was wetland in its entirety. However, communities established on pahoehoe lava flows contained scattered wetlands in depressions and folds in the lava, where water could accumulate. Therefore, large construction projects, such as that associated with proposed geothermal energy development in the area, have the potential to impact a significant number and/or area of wetlands. To estimate those impacts more accurately, they present a supplementary scope of work and cost estimate for additional sampling in the proposed geothermal project area.

Wakeley, J.S.; Sprecher, S.W.; Lichvar, R.

1994-02-25

263

High and Mid-Latitude Wetlands, Climate Change, and Carbon Storage  

NASA Technical Reports Server (NTRS)

Pollen and macrofossil stratigraphy from wetlands associated with AMS chronology provides a vegetational and climatic history over thousands of years. From these records we establish a record of climate change which can be compared with independent records of carbon accumulation rates in these same wetlands. In this way, inferences can be made concerning carbon storage during different climatic regimes. One focus of our research has been high-latitude regions such as Alaskan and Siberian tundra, from which we have paleorecords which span the last 10,000 years. We will present records from the Malaspina Glacier region, Alaska and the Pur-Taz region of Western Siberia. A second focus of our research is in mid-latitude eastern North America. We will present paleorecords from wetlands in Vermont, New York, and Virginia showing the relationship between carbon accumulation rates and climatic changes since the late Pleistocene.

Peteet, Dorothy

2000-01-01

264

Contiguity and edge characteristics of wetlands in five coastal counties of north Carolina, USA  

Microsoft Academic Search

Wetland contiguity and edge were determined with a geographic information system (GIS) for five coastal counties in North\\u000a Carolina. USA. The digital database was created from wetlands digitized from U.S. Fish and Wildlife Service National Wetlands\\u000a Inventory maps. The GIS analysis was based on three classes of information: 1) all wetlands as one class; 2) wetlands separated\\u000a by dominant vegetative

Kevin K. Moorhead

1999-01-01

265

What Makes a Wetland a Wetland?  

ERIC Educational Resources Information Center

Provides descriptions of and activities about various kinds of wetlands. Contains seven learning activities ranging from creating wetland scenes with picture cutouts to actually exploring a wetland. Includes reproducible handouts and worksheets for several of the activities. (TW)

Naturescope, 1986

1986-01-01

266

The Virginia Wetlands Report  

E-print Network

VWR -- 1 The Virginia Wetlands Report The Virginia Wetlands Report Winter/Spring 2000 Vol. 15, No. 1 Virginia Debates Nontidal Wetlands Regulation Carl Hershner Wetland regulation is once again- trolling impacts on existing wetlands, as well as creating new wetlands. There is general agreement

267

Late Holocene to present climatic and anthropogenic drivers affecting wetland plant communities, Florida Everglades, USA  

NASA Astrophysics Data System (ADS)

We synthesize the paleoecological results of dozens of sediment cores to evaluate the complex interactions of regional climate variability and anthropogenic modifications during the late Holocene affecting the development, stability, and resilience of the Florida Everglades wetlands. The Everglades is a mosaic of wetland types whose distributions are controlled by water depth, hydroperiod, fire, and substrate. External stressors could trigger shifts in the vegetation composition and change the community structure. Episodic severe periods of aridity during the late Holocene caused regional shifts in vegetation including the initiation and development of tree islands and sawgrass ridges, which became established during abrupt drought events. While the timing varies site to site, most droughts occurred during well-documented global climate events like the Medieval Climate Anomaly and the Little Ice Age. However, slough vegetation is more resilient to climate variability and quickly returns to its original composition after droughts. Twentieth century modification to the natural Everglades hydrology saw the distribution wetlands severely altered. The response was not homogeneous. Some communities were drowned by prolonged hydroperiods whereas other communities, such as marl prairies became drier. However, slough vegetation in the ridge and slough landscape did not respond to 20th century land use but instead has been sensitive to changes in precipitation associated with the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation.

Bernhardt, C. E.; Willard, D. A.

2011-12-01

268

Oxygen demand, nitrogen and copper removal by free-water-surface and subsurface-flow constructed wetlands under tropical conditions  

Microsoft Academic Search

This study was conducted to: (1) assess the role of wetland vegetation in the removal of oxygen demand and nitrogen under tropical conditions, (2) estimate the uptake of nitrogen and copper by wetland plants and (3) investigate the speciation of Cu in wetland media among four operationally defined host fractions, namely exchangeable, carbonate, reducible and organically bound. Four laboratory-scale wetland

P. E. Lim; T. F. Wong; D. V. Lim

2001-01-01

269

Potential for using native plant species in stormwater wetlands.  

PubMed

Spartina pectinata (prairie cordgrass) was grown under five hydroperiods (wet-dry cycles) to determine its potential for use in stormwater wetlands, particularly as an alternative to the highly invasive Phalaris arundinacea (an exotic grass). Rhizomes planted in outdoor microcosms grew vigorously in all treatments, namely, weekly flooding in early summer, weekly flooding in late summer, flooding every three weeks throughout the summer, weekly flooding throughout the summer, and no flooding. Neither the timing nor frequency of 24-hour floods (10-20 cm deep) affected total stem length (grand mean 1003 +/- 188.8 cm per pot, n = 140) or above-ground biomass (46.5 +/- 8.3 g per pot, equivalent to approximately 360 g/m2). However, by late summer, fewer new tillers were found in unflooded microcosms, indicating that vegetative expansion is drought-sensitive. The growth of Spartina plants was further assessed with and without Glyceria striata (a native grass) and Phalaris arundinacea. Glyceria growth was not affected by hydrologic treatment. Glyceria reduced Spartina growth by approximately 11%, suggesting potential as a cover crop that might reduce establishment and growth of Phalaris seedlings. Seeds of Phalaris did not germinate, but branch fragments established where soil was moist from flooding, regardless of the presence of Glyceria. The ability of Spartina to establish vegetatively and grow well under variable water levels leads us to recommend further testing in stormwater wetlands, along with early planting of Glyceria to reduce weed invasions. PMID:11830768

Bonilla-Warford, Cristina M; Zedler, Joy B

2002-03-01

270

The influence of papermill sludge application on the biogeochemistry and vegetation of young red pine (Pinus resinosa Ait. ) plantations established in recent clearcut forest ecosystems  

SciTech Connect

Combined primary and secondary papermill sludge was applied to three young red pine (Pinus resinosa Ait.) plantation (age < 8 years) in western Maine. Field studies were conducted to evaluate the influence of sludge application on forest soil chemical and physical properties, soil solution and streamwater chemistry, and conifer and competitive vegetation growth. Research sites were established in Letter E Township, Jim Pond Township, and Coplin Plantation. At Letter E, study plots were established in an adjacent uncut forest area, in order to examine the effects of clearcut harvesting on forest ecosystem biogeochemical processes. A seedling study was also established to examine the effect of sludge application on newly-planted tree species: japanese larch (Lariz leptolepis), red pine (Pinus resinosa Ait.), and black spruce (Picea mariana(Mill.) B.S.P.). Sludge was operationally applied during the summer and fall of 1989. The target loading rate was 40 Mg ha[sup [minus]1]. Harvesting at the Letter E site appeared to increase concentrations of major nutrients in soil solution. In 1989, soil solution Ca[sup 2+], Mg[sup 2+], and NO[sub 3][sup [minus

Kraske, C.R.

1992-01-01

271

Remote Sensing and Wetland Ecology: a South African Case Study  

PubMed Central

Remote sensing offers a cost efficient means for identifying and monitoring wetlands over a large area and at different moments in time. In this study, we aim at providing ecologically relevant information on characteristics of temporary and permanent isolated open water wetlands, obtained by standard techniques and relatively cheap imagery. The number, surface area, nearest distance, and dynamics of isolated temporary and permanent wetlands were determined for the Western Cape, South Africa. Open water bodies (wetlands) were mapped from seven Landsat images (acquired during 1987 – 2002) using supervised maximum likelihood classification. The number of wetlands fluctuated over time. Most wetlands were detected in the winter of 2000 and 2002, probably related to road constructions. Imagery acquired in summer contained fewer wetlands than in winter. Most wetlands identified from Landsat images were smaller than one hectare. The average distance to the nearest wetland was larger in summer. In comparison to temporary wetlands, fewer, but larger permanent wetlands were detected. In addition, classification of non-vegetated wetlands on an Envisat ASAR radar image (acquired in June 2005) was evaluated. The number of detected small wetlands was lower for radar imagery than optical imagery (acquired in June 2002), probably because of deterioration of the spatial information content due the extensive pre-processing requirements of the radar image. Both optical and radar classifications allow to assess wetland characteristics that potentially influence plant and animal metacommunity structure. Envisat imagery, however, was less suitable than Landsat imagery for the extraction of detailed ecological information, as only large wetlands can be detected. This study has indicated that ecologically relevant data can be generated for the larger wetlands through relatively cheap imagery and standard techniques, despite the relatively low resolution of Landsat and Envisat imagery. For the characterisation of very small wetlands, high spatial resolution optical or radar images are needed. This study exemplifies the benefits of integrating remote sensing and ecology and hence stimulates interdisciplinary research of isolated wetlands.

De Roeck, Els R.; Verhoest, Niko E.C.; Miya, Mtemi H.; Lievens, Hans; Batelaan, Okke; Thomas, Abraham; Brendonck, Luc

2008-01-01

272

Macroinvertebrate abundance, water chemistry, and wetland characteristics affect use of wetlands by avian species in Maine  

USGS Publications Warehouse

Our objective was to determine use by avian species (e.g., piscivores, marsh birds, waterfowl, selected passerines) of 29 wetlands in areas with low ( 5.51. All years combined use of wetlands by broods was greater on wetlands with pH 5.51 that supported 21.8% of the broods. High mean brood density was associated with mean number of Insecta per wetland. For lentic wetlands created by beaver, those habitats contained vegetative structure and nutrients necessary to provide cover to support invertebrate populations that are prey of omnivore and insectivore species. The fishless status of a few wetlands may have affected use by some waterfowl species and obligate piscivores.

Longcore, J.R.; McAuley, D.G.; Pendleton, G.W.; Bennatti, C.R.; Mingo, T.M.; Stromborg, K.L.

2006-01-01

273

Competitive effect versus competitive response of invasive and native wetland plant species.  

PubMed

Non-native plants can have adverse effects on ecosystem structure and processes by invading and out-competing native plants. I examined the hypothesis that mature plants of non-native and native species exert differential effects on the growth of conspecific and heterospecific seedlings by testing predictions that (1) invasive vegetation has a stronger suppressive effect on seedlings than does native vegetation, (2) seedlings of invasive species are better able to grow in established vegetation than are native seedlings, and (3) invasive species facilitate conspecific and inhibit heterospecific seedling growth. I measured growth rates and interaction intensities for seedlings of four species that were transplanted into five wetland monoculture types: invasive Lythrum salicaria; native L. alatum, Typha angustifolia, T. latifolia; unvegetated control. Invasive L. salicaria had the strongest suppressive effect on actual and per-individual bases, but not on a per-gram basis. Seedlings of T. latifolia were better able to grow in established vegetation than were those of L. salicaria and T. angustifolia. These results suggest that L. salicaria is not a good invader of established vegetation, but once established, it is fairly resistant to invasion. Thus, it is likely that disturbance of established vegetation facilitates invasion by L. salicaria, allowing it to compete with other species in even-aged stands where its high growth rate and consequent production of aboveground biomass confer a competitive advantage. PMID:14758534

Hager, Heather A

2004-03-01

274

Effects of sedge and cottongrass tussocks on plant establishment patterns in a post-mined peatland, northern Japan  

Microsoft Academic Search

Facilitation (positive inter-specific interaction) plays an important role in promoting succession in harsh environments.\\u000a To examine whether tussocks facilitate the establishment of other species, after peat mining, investigations were carried\\u000a out in a formerly Sphagnum-dominated wetland (Sarobetsu mire, northern Japan). Two tussock-forming species, Carex middendorffii and Eriophorum vaginatum, have established in sparsely vegetated areas, with a dry ground surface, since

Asuka Koyama; Shiro Tsuyuzaki

2010-01-01

275

7 CFR 1467.6 - Establishing priority for enrollment of properties in WRP.  

Code of Federal Regulations, 2010 CFR

...LOANS, PURCHASES, AND OTHER OPERATIONS WETLANDS RESERVE PROGRAM § 1467.6 Establishing...regions of the State where restoration of wetlands may better achieve State and regional...to the successful restoration of the wetlands and those adjacent landowners are...

2010-01-01

276

7 CFR 1467.6 - Establishing priority for enrollment of properties in WRP.  

Code of Federal Regulations, 2011 CFR

...LOANS, PURCHASES, AND OTHER OPERATIONS WETLANDS RESERVE PROGRAM § 1467.6 Establishing...regions of the State where restoration of wetlands may better achieve State and regional...to the successful restoration of the wetlands and those adjacent landowners are...

2011-01-01

277

7 CFR 1467.6 - Establishing priority for enrollment of properties in WRP.  

Code of Federal Regulations, 2012 CFR

...LOANS, PURCHASES, AND OTHER OPERATIONS WETLANDS RESERVE PROGRAM § 1467.6 Establishing...regions of the State where restoration of wetlands may better achieve State and regional...to the successful restoration of the wetlands and those adjacent landowners are...

2012-01-01

278

7 CFR 1467.6 - Establishing priority for enrollment of properties in WRP.  

...LOANS, PURCHASES, AND OTHER OPERATIONS WETLANDS RESERVE PROGRAM § 1467.6 Establishing...regions of the State where restoration of wetlands may better achieve State and regional...to the successful restoration of the wetlands and those adjacent landowners are...

2014-01-01

279

7 CFR 1467.6 - Establishing priority for enrollment of properties in WRP.  

Code of Federal Regulations, 2013 CFR

...LOANS, PURCHASES, AND OTHER OPERATIONS WETLANDS RESERVE PROGRAM § 1467.6 Establishing...regions of the State where restoration of wetlands may better achieve State and regional...to the successful restoration of the wetlands and those adjacent landowners are...

2013-01-01

280

Wetlands ecology  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. The ERTS imagery analyzed provides approximately 2/3 coverage of the test site. Analysis was made using visual methods, density slicing, and multispectral analysis. Preliminary conclusions reached are that most, if not all, of the investigation objectives can be met. Saline and near-saline wetlands can be delineated from ERTS-1 images as the wetland-upland boundaries and land-water interface are clearly defined. Major plant species or communities such as Spartina alterniflora (high and low vigor forms), Spartina patens/Distichlis spicata, and Juncus roemarianus can be discriminated and spoil disposal areas identified.

Anderson, R. R. (principal investigator); Carter, V. L.; Mcginness, J. W., Jr.

1972-01-01

281

Hardwood re-sprout control in hydrologically restored Carolina Bay depression wetlands.  

SciTech Connect

Carolina bays are isolated depression wetlands located in the upper coastal plain region of the eastern Unites States. Disturbance of this wetland type has been widespread, and many sites contain one or more drainage ditches as a result of agricultural conversion. Restoration of bays is of interest because they are important habitats for rare flora and fauna species. Previous bay restoration projects have identified woody competitors in the seedbank and re-sprouting as impediments to the establishment of herbaceous wetland vegetation communities. Three bays were hydrologically restored on the Savannah River Site, SC, by plugging drainage ditches. Residual pine/hardwood stands within the bays were harvested and the vegetative response of the seedbank to the hydrologic change was monitored. A foliar herbicide approved for use in wetlands (Habitat® (Isopropylamine salt of Imazapyr)) was applied on one-half of each bay to control red maple (Acer rubrum L.), sweet gum (Liquidambar styraciflua L.), and water oak (Quercus nigra L.) sprouting. The effectiveness of the foliar herbicide was tested across a hydrologic gradient in an effort to better understand the relationship between depth and duration of flooding, the intensity of hardwood re-sprout pressure, and the need for hardwood management practices such as herbicide application.

Moser, Lee, Justin

2009-06-01

282

Buffer zone and windbreak effects on spray drift deposition in a simulated wetland.  

PubMed

The amount of agricultural spray that drifts into a wetland from an adjacent crop field is influenced by vegetation along the field boundary or any intentional setback distance (buffer zone) between the sprayer and the edge of the arable field. In this study, spray tracer drift deposits were measured in a simulated wetland area under different conditions of wind speed and buffer zone width. The effect of an artificial windbreak at the upwind edge of the simulated wetland was also evaluated. A level of tolerance of 0.1% of the in-swath spray deposition was established as a no-effect level for the response of aquatic plants to common herbicides. Our results indicate that a vegetated 10-m field margin (eg a fencerow) alone provides adequate protection from herbicide drift into a wetland area under wind conditions normally considered acceptable for spraying. For high winds (> 4m s(-1)) when field spraying would not normally be advised, adequate protection was afforded by the same 10-m margin plus a dense windbreak (25% porosity) or by the margin plus a 20-m buffer zone. PMID:15532682

Brown, Ralph B; Carter, Margaret H; Stephenson, Gerald R

2004-11-01

283

Vegetation and soils  

USGS Publications Warehouse

Intro paragraph: Characterization of bottomland hardwood vegetation in relatively undisturbed forests can provide critical information for developing effective wetland creation and restoration techniques and for assessing the impacts of management and development. Classification is a useful technique in characterizing vegetation because it summarizes complex data sets, assists in hypothesis generation about factors influencing community variation, and helps refine models of community structure. Hierarchical classification of communities is particularly useful for showing relationships among samples (Gauche 1982).

Burke, M.K.; King, S.L.; Eisenbies, M.H.; Gartner, D.

2000-01-01

284

Subtropical reservoir shorelines have reduced plant species and functional richness compared with adjacent riparian wetlands  

NASA Astrophysics Data System (ADS)

Dam construction has large negative effects on biodiversity in river and riparian ecosystems worldwide. This study aimed to determine whether reservoir shorelines had lower plant species diversity and functional diversity than unregulated or lightly regulated riparian wetlands and to examine the responses of plant diversity and functional traits to reservoir shoreline environmental gradients. We surveyed 146, 44, and 67 plots on reservoir shorelines and in mainstem and tributary riparian wetlands, respectively, in a subtropical river-reservoir system. Species richness, functional richness, evenness, and divergence were calculated to reflect the species and functional diversity of plant communities. Environmental factors including elevation above water level, slope, landform type, substrate, disturbance, and cover were measured. The results showed that both species and functional richness were significantly lower on reservoir shorelines than in riparian wetlands. The relative species number of clonal plants and relative cover of annual plants were both negatively related to slope and elevation. Structural equation modeling and other statistical analyses indicated that most environmental factors had significant effects on species and functional richness on reservoir shorelines but had no significant effect on functional evenness and divergence. Our findings suggest that reservoir shoreline wetlands formed by damming rivers and inundating pre-existing riparian wetlands can be a biodiversity coldspot in regulated rivers at the plot level. Topographic factors are important in determining the plant diversity and vegetation establishment on reservoir shorelines in the Yangtze River basin.

Liu, Wenzhi; Liu, Guihua; Liu, Hui; Song, Yu; Zhang, Quanfa

2013-12-01

285

Global warming and prairie wetlands: potential consequences for waterfowl habitat  

USGS Publications Warehouse

The accumulation of greenhouse gasses in the atmosphere is expected to warm the earth's climate at an unprecedented rate (Ramanathan 1988, Schneider 1989). If the climate models are correct, within 100 years the earth will not only be warmer than it has been during the past million years, but the change will have occurred more rapidly than any on record. Many profound changes in the earth's environment are expected, including rising sea level, increasing aridity in continental interiors, and melting permafrost. Ecosystems are expected to respond variously to a rapidly changing climate. Tree ranges in eastern North American are expected to shift northward, and seed dispersal may not be adequate to maintain current diversity (Cohn 1989, Johnson and Webb 1989). In coastal wetlands, rising sea level from melting icecaps and thermal expansion could flood salt-grass marshes and generally reduce the size and productivity of the intertidal zone (Peters and Darling 1985). As yet, little attention has been given to the possible effects of climatic warming on inland prairie wetland ecosystems. These wetlands, located in the glaciated portion of the North American Great Plains (Figure 1), constitute the single most important breeding area for waterfowl on this continent (Hubbard 1988). This region annually produces 50-80% of the continent's total duck production (Batt et al. 1989). These marshes also support a variety of other wildlife, including many species of nongame birds, muskrat, and mink (Kantrud et al. 1989a). Prairie wetlands are relatively shallow, water-holding depressions that vary in size, water permanence, and water chemistry. Permanence types include temporary ponds (typically holding water for a few weeks in the springs), seasonal ponds (holding water from spring until early summer), semipermanent ponds (holding water throughout the growing season during most years), and large permanent lakes (Stewart and Kantrud 1971). Refilling usually occurs in spring from precipitation and runoff from melting snow on frozen or saturated soils (Figure 2). Annual water levels fluctuate widely due to climate variability in the Great Plains (Borchert 1950, Kantrud et al. 1989b). Climate affects the quality of habitat for breeding waterfowl by controlling regional water conditions--water depth, areal extent, and length of wet/dry cycles (Cowardin et al. 1988)--and vegetation patterns such as the cover ration (the ratio of emergent plant cover to open water). With increased levels of atmospheric carbon dioxide, climate models project warmer and, in some cases, drier conditions for the northern Great Plains (Karl et al. 1991, Manabe and Wetherald 1986, Mitchell 1983, Rind and Lebedeff 1984). In general, a warmer, drier climate could lower waterfowl production directly by increasing the frequency of dry basins and indirectly by producing less favorable cover rations (i.e., heavy emergent cover with few or no open-water areas). The possibility of diminished waterfowl production in a greenhouse climate comes at a time when waterfowl numbers have sharply declined for other reasons (Johnson and Shaffer 1987). Breeding habitat continues to be lost or altered by agriculture, grazing, burning, mowing, sedimentation, and drainage (Kantrud et al. 1989b). For example, it has been estimated that 60% of the wetland area in North Dakota has been drained (Tiner 1984). Pesticides entering wetlands from adjacent agricultural fields have been destructive to aquatic invertebrate populations and have significantly lowered duckling survival (Grue et al. 1988). In this article, we discuss current understanding and projections of global warming; review wetland vegetation dynamics to establish the strong relationship among climate, wetland hydrology, vegetation patterns, and waterflow habitat; discuss the potential effects of a greenhouse warming on these relationships; and illustrate the potential effects of climate change on wetland habitat by using a simulation model. The extent to which intensive management of the waterfowl resource will be needed in the f

Poiani, Karen A.; Johnson, W. Carter

1991-01-01

286

Saltwater Wetlands.  

ERIC Educational Resources Information Center

Provides information about saltwater wetlands. Contains seven learning activities which deal with "making" a mud snail, plants and animals of mangroves, and the effects of tides on salt marshes. Included are reproducible handouts and worksheets for several of the activities. (TW)

Naturescope, 1986

1986-01-01

287

Final Report: Five years of monitoring reconstructed freshwater tidal wetlands in the urban Anacostia River (2000-2004)  

USGS Publications Warehouse

The Anacostia River in Washington, D.C. USA consisted of over 809 hectares (2000 acres) of freshwater tidal wetlands before mandatory dredging removed most of them in the first half of the 20th century. Much of this13 kilometer (8 mile) reach was transferred to the National Park Service (NPS). Planning processes in the 1980?s envisioned a restoration (rejuvenation) of some wetlands for habitat, aesthetics, water quality and interpretative purposes. Subsequently, the U.S. Army Corps of Engineers in a cost share agreement with the District of Columbia reconstructed wetlands on NPS lands at Kenilworth - 12.5 hectares (1993), Kingman - 27 hectares (2000), a Fringe Marsh - 6.5 hectares (2003) and is currently constructing Heritage Marsh - 2.5 hectares (2005/2006). The USGS Patuxent Wildlife Research Center in conjunction with the University of Maryland Biological Engineering Department was contracted to conduct post-reconstruction monitoring (2000-2004) to document the relative success and progress of the Kingman Marsh reconstruction primarily based on vegetative response but also in conjunction with seed bank and soil characteristics. Results from Kingman were compared to Kenilworth Marsh (reconstructed 7 years prior), Dueling Creek Marsh (last best remaining freshwater tidal wetland bench in the urbanized Anacostia watershed) and Patuxent River Marsh (in a more natural adjacent watershed). Vegetation establishment was initially strong at Kingman, but declined rapidly as measured by cover, richness, diversity , etc. under grazing pressure from resident Canada geese and associated reduction in sediment levels. This decline did not occur at the other wetlands. The decline occurred despite a substantial seed bank that was sustained primarily be water born propagules. Soil development, as true for most juvenile wetlands, was slow with almost no organic matter accumulation. By 2004 only two of 7 planted species remained (mostly Peltandra virginica) at Kingman which did provide almost 50% of the approximately 1/3 total vegetation cover remaining.

Hammerschlag, R.S.; Baldwin, A.H.; Krafft, C.C.; Neff, K.P.; Paul, M.M.; Brittingham, K.D.; Rusello, K.; Hatfield, J.S.

2006-01-01

288

The Virginia Wetlands Report  

E-print Network

The Virginia Wetlands Report Summer 1997 Vol. 12, No. 2The Virginia Wetlands Report Wetlands mitigation banking is a relatively new tool for wetlands managers. It is finding increasing application in the struggle to achieve a "no net loss" goal for our remaining wetland resources. The concept of creating

289

The Virginia Wetlands Report  

E-print Network

VWR -- 1 The Virginia Wetlands Report The Virginia Wetlands Report Spring 2005 Vol. 20, No. 1 Annual Summary of Permitted Tidal Wetland Impacts - 2004 By Karen Duhring The Wetlands Program has main impact areas based on a site visit and information provided in the permit documents. The Wetlands Program

290

The Virginia Wetlands Report  

E-print Network

VWR -- 1 The Virginia Wetlands Report The Virginia Wetlands Report Fall 2005 Vol. 20, No. 2 VMRC Adopts Wetland Mitigation/ Compensation Policy Changes By Tom Barnard When the Virginia Wetlands Act went into effect on July 1, thirty- three years ago, no one had ever heard of compensatory mitigation, wetland

291

A comparative study on the potential of oxygen release by roots of selected wetland plants  

NASA Astrophysics Data System (ADS)

The capacity of root oxygen release by selected wetland plants pre-grown under both nutrient solution and artificial wastewater conditions were determined. The results indicated that the significant differences of root oxygen release by the tested wetland plants existed, and the biochemical process was the main source of root oxygen release as oxygen released by Vetiveria zizanioides L. Nash roots through biochemical process was contributed to 77% and 74% of total root oxygen release under nutrient solution conditions and artificial wastewater conditions, respectively, and that was 72% and 71% of total root oxygen release for Cyperus alternifolius L. It was found that the formation of root plaque with iron oxide was a function of root oxygen release as iron oxide concentration in root plaque was positively correlated to the potential of oxygen released by wetland plant roots with the regression coefficients as 0.874 *( p < 0.05) under nutrient solution conditions and 0.944 **( p < 0.01) under artificial wastewater conditions, which could be regarded as an important mechanism of wetland plants being tolerant to anoxia during wastewater treatment. It was suggested that the potential of root oxygen release could be used as a parameter for selecting wetland plants that can increase oxygen supply to soil or substrate of constructed wetlands and enhance nutrient transformation and removal, and V. zizanioides L. Nash with the highest potential of root oxygen release and higher tolerance to wastewater could be recommended to establish vegetated wetlands for treating nutrient-rich wastewater such as domestic wastewater.

Yao, Fang; Shen, Gen-xiang; Li, Xue-lian; Li, Huai-zheng; Hu, Hong; Ni, Wu-zhong

292

Aquifers and Wetlands SUMMARY: This chapter begins with an overview of the hydrological cycle and  

E-print Network

Chapter 14 Aquifers and Wetlands SUMMARY: This chapter begins with an overview of the hydrological cycle and considers the flow of water in wetlands and undergraound. Special attention is paid to flow through vegetated wetlands. 14.1 The Hydrological Cycle Rivers and streams are but a link in the global

Cushman-Roisin, Benoit

293

Constructed Farm Wetlands (CFWs) designed for remediation of farmyard runoff: an  

E-print Network

Constructed Farm Wetlands (CFWs) designed for remediation of farmyard runoff: an evaluation and help achieve compliance with the Water Framework Directive, Constructed Farm Wetlands (CFWs), i.e. shallow surface flow wetlands comprising several vegetated cells in series, are being recommended

294

Rapid Invasion of a Great Lakes Coastal Wetland by Non-native Phragmites australis and Typha  

Microsoft Academic Search

Great Lakes coastal wetlands are subject to water level fluctuations that promote the maintenance of coastal wetlands. Point au Sauble, a Green Bay coastal wetland, was an open water lagoon as of 1999, but became entirely vegetated as Lake Michigan experienced a prolonged period of below-average water levels. Repeat visits in 2001 and 2004 documented a dramatic change in emergent

Mirela G. Tulbure; Carol A. Johnston; Donald L. Auger

2007-01-01

295

Methane emission from natural wetlands: Global distribution, area, and environmental characteristics of sources  

Microsoft Academic Search

A global data base of wetlands at 1 degree resolution was developed from the integration of three independent global, digital sources: (1) vegetation, (2) soil properties and (3) fractional inundation in each 1 degree cell. The integration yielded a global distribution of wetland sites identified with in situ ecological and environmental characteristics. The wetland sites were classified into five major

Elaine Matthews; Inez Fung

1987-01-01

296

COMPARISON OF CREATED AND NATURAL FRESHWATER EMERGENT WETLANDS IN CONNECTICUT  

EPA Science Inventory

Five three- to four-year old created palustrine/emergent wetland sites were compared with five nearby natural wetlands of comparable size and type. ydrologic, soil and vegetation data were compiled over a nearly two-year period (1988-90). reated sites, which were located along ma...

297

Invasive Plant Species in Diked vs. Undiked Great Lakes Wetlands  

Microsoft Academic Search

We compared the standing vegetation, seed banks, and substrate conditions in seven pairs of diked and undiked wetlands near the shores of Lake Michigan and Lake Huron, North America. Our analysis tested the null hypothesis that construction of artificial dikes has no effect on the vulnerability of Great Lakes coastal wetlands to non-native and native invasive species. Both the standing

Bradley M. Herrick; Amy T. Wolf

2005-01-01

298

TECHNICAL ARTICLES PLANTS USED IN CONSTRUCTED WETLANDS AND THEIR  

E-print Network

TECHNICAL ARTICLES #12;2 PLANTS USED IN CONSTRUCTED WETLANDS AND THEIR FUNCTIONS Hans Brix Department of Plant Ecology, Institute of Biological Sciences, University of Aarhus, Nordlandsvej 68, 8240 Risskov, Denmark ABSTRACT Vegetation plays an important role in wastewater treatment wetlands. Plants

Brix, Hans

299

Classification of land-cover types in muddy tidal flat wetlands using remote sensing data  

NASA Astrophysics Data System (ADS)

Remote sensing classification of tidal flat wetlands is important for obtaining high-precision information on wetland features. In this study, Thematic Mapper (TM) images of the Yancheng National Reserves, Jiangsu Province, China, for the years of 1996, 2002, 2006, and 2010 were considered. First, the optimum combination of bands was chosen. Second, vegetation and nonvegetation regions of interest were established to investigate the spectral reflectance characteristics of the different ground objects. Then we used the knowledge-based decision tree method on different features, such as the normalized difference vegetation index and the spectral reflectance. In particular, the ancillary information is helpful to distinguish the vegetation classes. The results demonstrate that the classification system has advantages in identifying the types of vegetation in ecotones, and it is 4 percentage points higher than the maximum likelihood method in classification accuracy. This study is useful to discriminate vegetation, and it provides an important reference for the effective extraction of tidal flat land-cover information from TM images.

Wang, Cong; Liu, Hong-Yu; Zhang, Ying; Li, Yu-feng

2013-01-01

300

AVIRIS spectra of California wetlands  

NASA Technical Reports Server (NTRS)

Spectral data gathered by the AVIRIS from wetlands in the Suisun Bay area of California on 13 October 1987 were analyzed. Spectra representing stands of numerous vegetation types (including Sesuvium verrucosum, Scirpus acutus and Scirpus californicus, Xanthium strumarium, Cynadon dactylon, and Distichlis spicata) and soil were isolated. Despite some defects in the data, it was possible to detect vegetation features such as differences in the location of the chlorophyll red absorption maximum. Also, differences in cover type spectra were evident in other spectral regions. It was not possible to determine if the observed features represent noise, variability in canopy architecture, or chemical constituents of leaves.

Gross, Michael F.; Ustin, Susan L.; Klemas, Vytautas

1988-01-01

301

Riparian Wetlands: Mapping  

EPA Science Inventory

Riparian wetlands are critical systems that perform functions and provide services disproportionate to their extent in the landscape. Mapping wetlands allows for better planning, management, and modeling, but riparian wetlands present several challenges to effective mapping due t...

302

WETLAND DETECTION METHODS INVESTIGATION  

EPA Science Inventory

The purpose of this investigation was to research and document the application of remote sensing technology for wetlands detection. arious sensors and platforms are evaluated for: suitability to monitor specific wetland systems; effectiveness of detailing wetland extent and capab...

303

Our Valuable Wetlands.  

ERIC Educational Resources Information Center

Defines wetlands and lists several types of wetland habitat. Describes explorations that can be done with secondary school students including the baby boom, a food pyramid, and microenvironments. Includes a classroom poster with text on the variety of wetlands. (CW)

Texley, Juliana

1988-01-01

304

Application of Systems Model and Remote Sensing Images to Improve Wetland Management  

NASA Astrophysics Data System (ADS)

Wetlands are complex ecosystem that involves interaction among hydrological, ecological and spatial-temporal considerations. Also, water shortages and invasive vegetation are common problems in wetlands. The present paper has the purpose to contribute with the solution of these problems: (i) Providing a tool to wetland managers to monitor changes in vegetation cover and wetland hydrology over time; (ii) Finding a relationship between vegetation response and key hydrological attributes in wetlands and (iii) Incorporating these relationship in an optimization model to recommend water allocation and invasive vegetation control to improve wetland management. This research is applied at the Bear River Migratory Bird Refuge (the Refuge), located on the northeast side of Great Salt Lake, Utah. The Refuge constitutes one of the most important habitats for migratory birds for the Pacific Flyway of North America. Water measures and coverage vegetation collected in-situ at the Refuge has been used to calibrate and evaluate the effects on wetland plant communities to the process of flooding and drought in wetland units during different years. A MATLAB-based algorithm has been developed to process LandSat images to estimate the interaction between flooded areas and invasive vegetation cover. These interactions are embedded in a system optimization model to recommend water allocations and vegetation control actions among diked wetland units that improve wetland habitat for wildlife species. This modeling effort identify the interaction between invasive vegetation and flood wetland areas and embed those interactions in a systems model that wetland managers can use to make informed decisions about allocation of water and manage vegetation cover.

Alminagorta, O.; Torres-Rua, A. F.

2013-05-01

305

Wetland Boundary Determination in the Great Dismal Swamp Using Weighted Averages  

USGS Publications Warehouse

A weighted average method was used to analyze transition zone vegetation in the Great Dismal Swamp to determine if a more uniform determination of wetland boundaries can be made nationwide. The method was applied to vegetation data collected on four transects and three vertical layers across the wetland-to-upland transition zone of the swamp. Ecological index values based on water tolerance were either taken from the literature or derived from local species tolerances. Wetland index values were calculated for 25-m increments using species cover and rankings based on the ecological indices. Wetland index values were used to designate increments as either wetland, transitional, or upland, and to examine the usefulness of a provisional wetland-upland break-point. The weighted average method did not provide for an objective placement of an absolute wetland boundary, but did serve to focus attention on the transitional boundary zone where supplementary information is necessary to select a wetland-upland breakpoint.

Carter, Virginia; Garrett, Mary, Keith; Gammon, Patricia, T.

1988-01-01

306

Artificial Wetlands  

NSDL National Science Digital Library

Golf courses are known as places of recreation. But some of them could someday double as water treatment facilities. Water hazards on golf courses can be used to control environmental hazards. That's according to Purdue University soil microbiologist Ron Turco. He says the artificial wetlands can also control flooding in surrounding communities, by collecting excess water. This Science Update looks at the research, which leads to these findings and offers links to other resources for further inquiry.

American Association for the Advancement of Science (;)

2005-04-11

307

Feedbacks between flow, vegetation, deposition, and the implications for landscape development  

E-print Network

Flow and sedimentation around patches of vegetation are important to landscape evolution, and a better understanding of these processes would facilitate more effective river restoration and wetlands engineering. In wetlands ...

Kondziolka, John M. (John Michael)

2014-01-01

308

Comparison of created and natural freshwater emergent wetlands in Connecticut (USA)  

Microsoft Academic Search

Five three- to four-year old created palustrine\\/emergent wetland sites were compared with five nearby natural wetlands of comparable size and type. Hydrologic, soil and vegetation data were compiled over a nearly two-year period (1988-90). Created sites, which were located along major highways, exhibited more open water, greater water depth, and greater fluctuation in water depth than natural wetlands. Typical wetland

Sheri R. Confer; William A. Niering

1992-01-01

309

Geomorphic and hydrogeologic controls on wetland distribution in the New South Wales Southern Highlands, south east Australia: prioritising natural resource management investment.  

NASA Astrophysics Data System (ADS)

Strategic investment of public funds in wetland conservation on the New South Wales (NSW) Southern Tablelands, in south east Australia, is impeded by poor understanding of the distribution of wetlands and their geomorphic and hydrogeologic setting. Appropriate investment and management is also unclear in the face of climate change. This research detailed: the spatial configuration, the hydrogeological setting, and intrinsic ecological value of the wetlands. Using this modelling, potential impact of climate change on wetlands was examined. Previous work developed a draft typology for Southern Tablelands wetlands, expanded techniques for representing spatial variability in wetland biodiversity (using generalised dissimilarity models) and explored methods of modelling wetland location through integration of hydrology, terrain and geological features. This new work integrated the mapping of the spatial distribution of a range of wetland types with a hydrogeological landscape (HGL) framework in order to better understand the movement of water through wetland landscapes. The process of HGL determination relies on the integration of a number of factors including: geology, soils, slope, regolith thickness, vegetation and climate. If the distribution of regolith materials, fractured rock and barriers to flow are characterised, an understanding of surface and sub-surface fluid pathways can be established. Contextualising a study of wetlands in an HGL framework is useful because it provides information about the biophysical controls that influence why wetlands occur in some parts of the landscape and not others. Each HGL unit spatially defines areas with similar controls on movement of water and hence similar patterns of surface and groundwater connectivity. The NSW Southern Highland landscape was divided into 34 HGL units, based on derived spatial information and field observations. Each HGL unit had an associated conceptual model, identifying potential surface water and groundwater pathways. These models were then field tested by collating and interpreting the widest possible range of biophysical parameters, in order to enhance the rigour of the models. In parallel, wetland mapping identified 4 main wetland types: upland hanging swamps, upland bogs or fens, upland freshwater lakes and riverine wetlands. The wetland types were linked with their contemporary geomorphic setting and then integrated with the HGL framework enabling identification of the wetland 'plumbing' context. These integrated wetland HGL units were evaluated with respect to the NSW Climate Impact Profile for the south east NSW region (min. T increase 1-3°C; max T. increase 2-3°C; rainfall 20-50% summer increase, 20-50% winter decrease; 10-20% evaporation increase). This scenario-based modelling provides an accurate measure of sensitivity of the wetlands to change and allows evaluation of the capacity for a wetland to adapt to change. If landscape variation, the biophysical character of wetlands, the hydrogeological context, and hence the influences of surface and groundwater systems are understood, then we can identify NRM hazards and prioritise wetland management. The premise is that if we understand the natural processes that result in particular outcomes in a landscape, then strategic decisions about whether to intervene, how to intervene, or whether it is worth doing so, can be made.

Cowood, Alie; Moore, Leah

2014-05-01

310

Organic phosphorus sequestration in subtropical treatment wetlands.  

PubMed

Diffuse phosphorus pollution is commonly remediated by diverting runoff through treatment wetlands to sequester phosphorus into soil layers. Much of the sequestered phosphorus occurs in organic forms, yet our understanding of its chemical nature is limited. We used NaOH-EDTA extraction and solution 31P NMR spectroscopy to speciate organic phosphorus sequestered in a large treatment wetland (STA-1W) in Florida, USA. The wetland was constructed on previously farmed peat and was designed to remove phosphorus from agricultural runoff prior to discharge into the Everglades. Unconsolidated benthic floc that had accumulated during the 9-year operation of the wetland was sampled along transects through two connected cells dominated by cattail (Typha dominigensis Pers.) and an additional cell colonized by submerged aquatic vegetation, including southern water nymph (Najas guadalupensis(Spreng.) Magnus) and coontail (Ceratophyllum demersum L.). Organic phosphorus was a greater proportion of the sequestered phosphorus in the cattail marsh compared to the submerged aquatic vegetation wetland, but occurred almost exclusively as phosphate diesters and their alkaline hydrolysis products. Itwas therefore markedly different from the organic phosphorus in mineral soils, which is dominated typically by inositol phosphates. Phosphate diesters are readily degradable in most soils, raising concern about the long-term fate of organic phosphorus in treatment wetlands. Further studies are now necessaryto assess the stability of the sequestered organic phosphorus in response to biogeochemical and hydrological perturbation. PMID:16509310

Turner, Benjamin L; Newman, Susan; Newman, Jana M

2006-02-01

311

Relationship between hydrology and zonation of freshwater swale wetlands on lower hatteras island, North Carolina, USA  

Microsoft Academic Search

Only a few relatively wide barrier islands support shallow freshwater aquifers. Rare, swale wetlands occur on islands where\\u000a fresh water inundates, at least seasonally, low-lying troughs between interior dunes. Swale wetlands are dominated by emergent\\u000a vegetation and submerged aquatic vegetation in the deepest areas and by woody shrubs in more shallow areas. On southern Hatteras\\u000a Island, wetland shrubs have progressively

Richard D. Rheinhardt; Karl Faser

2001-01-01

312

Emissions of sulfur gases from wetlands  

NASA Technical Reports Server (NTRS)

Data on the emissions of sulfur gases from marine and freshwater wetlands are summarized with respect to wetland vegetation type and possible formation mechanisms. The current data base is largest for salt marshes inhabited by Spartina alterniflora. Both dimethyl sulfide (DMS) and hydrogen sulfide (H2S) dominate emissions from salt marshes, with lesser quantities of methyl mercaptan (MeSH), carbonyl sulfide (COS), carbon disulfide (CS2) and dimethyl disulfide (DMDS) being emitted. High emission rates of DMS are associated with vegetation that produces the DMS precursor dimethylsulfonionpropionate (DMSP). Although large quantities of H2S are produced in marshes, only a small percentage escapes to the atmosphere. High latitude marshes emit less sulfur gases than temperate ones, but DMS still dominates. Mangrove-inhabited wetlands also emit less sulfur than temperate S. alterniflora marshes. Few data are available on sulfur gas emissions from freshwater wetlands. In most instances, sulfur emissions from temperate freshwater sites are low. However, some temperate and subtropical freshwater sites are similar in magnitude to those from marine wetlands which do not contain vegetation that produces DMSP. Emissions are low in Alaskan tundra but may be considerably higher in some bogs and fens.

Hines, Mark E.

1992-01-01

313

Hydroperiod and plant diversity in the wet meadow zone of glaciated prairie wetlands  

SciTech Connect

Stewart and Kantrud`s (1971) widely used wetland classification system does not recognize the large differences in hydroperiod and species diversity that often occur in the same vegetation zone in wetlands of different water permanence class (temporary, seasonal, semi-permanent). Research in eastern South Dakota wetlands in 1994 indicated that annual range in surface water/groundwater elevation within a zone varied inversely with permanence. For example, within the wet meadow zone, average annual water elevation range was 124 cm in temporary wetlands, 65 cm in seasonal wetlands, and 15 cm in semi-permanent wetlands. The number of dominant plants in this zone was strongly and positively correlated to the amount of annual fluctuation in water elevation, from an average of 5 species in the relatively stable, semi-permanent wetlands to 14 species in the ephemeral, temporary wetlands. These results have application to research in wetland restoration and climate change.

Boettcher, S.E.; Johnson, W.C. [South Dakota State Univ., Brookings, SD (United States)

1995-06-01

314

Wetland Losses and Human Impacts  

E-print Network

" Region! Mississippi Alluvial Valley Wetland Losses 77% of Hardwood Bottomland Forests 8.5 Million ha 2 Everglades Sacramento Valley Great Lakes Wetlands Hudson and James Bay Wetlands 30% of World's Wetlands 89 of Wetland Types in the United States ·US Wetlands Dominated by Peatland Lower 48 ·Forested Wetlands Most

Gray, Matthew

315

Wetland Losses and Human Impacts  

E-print Network

. ·Illinois = 2.8 mil ha. Midwest "Breadbasket" Region! Mississippi Alluvial Valley Wetland Losses 77 Everglades Sacramento Valley Great Lakes Wetlands Hudson and James Bay Wetlands 30% of World's Wetlands 89 of Wetland Types in the United States ·US Wetlands Dominated by Peatland Lower 48 ·Forested Wetlands Most

Gray, Matthew

316

Wetland resources investigation based on 3S technology  

NASA Astrophysics Data System (ADS)

Wetland is a special ecosystem between land and water . It can provide massive foods, raw material, water resources and habitat for human being, animals and plants, Wetlands are so important that wetlands' development, management and protection have become the focus of public attention ."3S" integration technology was applied to investigate wetland resources in Shandong Province ,the investigation is based on remote sensing(RS) information, combining wetlandrelated geographic information system(GIS) data concerning existing geology, hydrology, land, lakes, rivers, oceans and environmental protection, using the Global Positioning System (GPS) to determine location accurately and conveniently , as well as multi-source information to demonstrate each other based on "3S" integration technology. In addition, the remote sensing(RS) interpretation shall be perfected by combining house interpretation with field survey and combining interpretation results with known data.By contrasting various types of wetland resources with the TM, ETM, SPOT image and combining with the various types of information, remote sensing interpretation symbols of various types of wetland resources are established respectively. According to the interpretation symbols, we systematically interpret the wetland resources of Shandong Province. In accordance with the purpose of different work, we interpret the image of 1987, 1996 and 2000. Finally, various interpretation results are processed by computer scanning, Vectored, projection transformation and image mosaic, wetland resources distribution map is worked out and wetland resources database of Shandong Province is established in succession. Through the investigation, wetland resource in Shandong province can be divided into 4 major categories and 17 sub-categories. we have ascertained the range and area of each category as well as their present utilization status.. By investigating and calculating, the total area of wetland in Shandong Province is 1,712,200 hm2,which accounts for 7.58% of the total area of land in Shandong Province (not including the wetland in the shallow waters along the coast). Among them, area of river wetland is 286,746 hm2, area of lakes wetland is143,490 hm2, area of reservoir and pond wetland is 118,693 hm2, area of offshore and coastal wetland is 994,100 hm2, and area of other wetland is 169,171 hm2. On the basis of this, we can analyze the dynamic changes trend and the reasons: steady degenerating for natural wetlands, increasing year by year for artificial wetland, and the distribution pattern takes shape that the existing natural wetlands are being protected and the increase of new artificial wetlands is in conformity with the social development, so the situation of the wetland resources is developing towards a virtuous circle direction.

Lin, Hui; Jing, Haitao; Zhang, Lianpeng

2008-10-01

317

The Virginia Wetlands Report  

E-print Network

VWR -- 1 The Virginia Wetlands Report The Virginia Wetlands Report Spring 2002 Vol. 17, No. 1 Update On Virginia's New and Improved Nontidal Wetlands Program By Ellen Gilinsky, Ph.D. PWS Virginia wetlands program. Key changes included the provi- sion of additional jurisdic- tion over: excavation in all

318

The Virginia Wetlands Report  

E-print Network

VWR -- 1 The Virginia Wetlands Report The Virginia Wetlands Report Winter/Spring 2003 Vol. 18, No. 1 I n a recently published final report entitled, Assessing the Decision- making Process in Wetlands Richards report the results of their preliminary examination of how wet- lands boards balance wetlands

319

The Virginia Wetlands Report  

E-print Network

VWR -- 1 The Virginia Wetlands Report The Virginia Wetlands Report Fall 2001 Vol. 16, No. 3 A GIS Approach for Targeting Potential Wetlands Mitigation or Restoration Sites By Marcia Berman and Tamia vegeta- tion, islands, and wetlands. Most activi- ties enhance habitat for living resources, but also

320

The Virginia Wetlands Report  

E-print Network

The Virginia Wetlands Report Continued on page 2 Spring 1996 Vol. 11, No. 2The Virginia Wetlands Report Completely Updated The Wetlands Program of the Vir- ginia Institute of Marine Science has completed its update of the Vir- ginia Wetlands Management Hand- book, and with the aid of the Marine

321

The Virginia Wetlands Report  

E-print Network

VWR -- 1 The Virginia Wetlands Report The Virginia Wetlands Report Winter/Spring 2001 Vol. 16, No. 1 The VIMS Teaching Marsh: A Tidal Wetland Restoration and Education Project Karen Duhring Purpose wetlands education opportunities, including field lessons. Due to the vari- ety and geographic distribution

322

The Virginia Wetlands Report  

E-print Network

The Virginia Wetlands Report Winter/Spring 1998 Vol. 13, No. 1The Virginia Wetlands Report N o net loss of wetland resources is a goal frequently announced by policy makers and resource manag- ers. Most the challenge of measuring progress toward achieving the goals. Knowledge about how many wetlands

323

The Virginia Wetlands Report  

E-print Network

VWR -- 1 The Virginia Wetlands Report The Virginia Wetlands Report Summer 2000 Vol. 15, No. 2 Department of Environmental Quality (DEQ) Implementing Nontidal Wetlands Protection Mandate Ellen Gilinsky wetland resources, but which occur outside of federal regulation. The General Assembly was motivated

324

The Virginia Wetlands Report  

E-print Network

VWR 1 The Virginia Wetlands Report The Virginia Wetlands Report Summer 1999 Vol. 14, No. 2 Historic Wetland Loss in the Elizabeth River Walter I. Priest, III Introduction Since earliest colonial consumed many of the natural resources of the river basin, including its wetlands, forests, water quality

325

Wetlands Transects  

NSDL National Science Digital Library

Field work on local sites has many benefits. Often students are surprised to discover thriving ecosystems in the most familiar and ordinary places. In this activity students will lay out transect lines beside a local stream or river. There they will record species of plants and insects living around the stream. By doing so, students will learn how to use transect sampling techniques, use a variety of methods to sample species, and compare species diversity and density between parallel transects. This activity helps students gain experience in problem-solving, scientific processes, and communication and introduces the terms transect, wetland indicator plants, diversity, and sampling.

326

Muskrats ( Ondatra zibethicus) in treatment wetlands  

Microsoft Academic Search

Muskrat grazing can change treatment wetlands from being densely vegetated to a patchwork of open and emergent areas. Muskrats consume a portion of the annual net primary productivity, primarily rhizomes, but their mounds represent a greater share of this production. Densities of 20 or more animals per ha have been found, which can destroy the majority of the macrophyte standing

Robert H. Kadlec; John Pries; Heather Mustard

2007-01-01

327

Exploring Microbial Iron Oxidation in Wetland Soils  

NASA Astrophysics Data System (ADS)

Iron is one of the most abundant elements on earth and is essential for life. Because of its importance, iron cycling and its interaction with other chemical and microbial processes has been the focus of many studies. Iron-oxidizing bacteria (FeOB) have been detected in a wide variety of environments. Among those is the rhizosphere of wetland plants roots which release oxygen into the soil creating suboxic conditions required by these organisms. It has been reported that in these rhizosphere microbial iron oxidation proceeds up to four orders of magnitude faster than strictly abiotic oxidation. On the roots of these wetland plants iron plaques are formed by microbial iron oxidation which are involved in the sequestering of heavy metals as well organic pollutants, which of great environmental significance.Despite their important role being catalysts of iron-cycling in wetland environments, little is known about the diversity and distribution of iron-oxidizing bacteria in various environments. This study aimed at developing a PCR-DGGE assay enabling the detection of iron oxidizers in wetland habitats. Gradient tubes were used to enrich iron-oxidizing bacteria. From these enrichments, a clone library was established based on the almost complete 16s rRNA gene using the universal bacterial primers 27f and 1492r. This clone library consisted of mainly ?- and β-Proteobacteria, among which two major clusters were closely related to Gallionella spp. Specific probes and primers were developed on the basis of this 16S rRNA gene clone library. The newly designed Gallionella-specific 16S rRNA gene primer set 122f/998r was applied to community DNA obtained from three contrasting wetland environments, and the PCR products were used in denaturing gradient gel electrophoresis (DGGE) analysis. A second 16S rRNA gene clone library was constructed using the PCR products from one of our sampling sites amplified with the newly developed primer set 122f/998r. The cloned 16S rRNA gene sequences all represented novel culturable iron oxidizers most closely related to Gallionella spp. Based on their nucleotide sequences four groups could be identified, which were comparable to the DGGE banding pattern obtained before with the gradient tubes enrichments. The above mentioned nested PCR-DGGE method was used to study the distribution and community composition of Gallionella-like iron-oxidizing bacteria under the influence of plants species, soil depth, as well as season. Soil samples from Appels, Belgium, an intertidal, freshwater marsh known to hold intensive iron cycling, were taken from 5 different vegetation types in April, July and October 2007. Soil cores were sliced at 1-cm intervals and subjected to chemical and molecular analyses. The DGGE patterns showed that the community of iron-oxidizing bacteria differed with vegetation type, and sediment depth. Samples taken in autumn held lower diversity in Gallionella-related iron oxidizers than those sampled in spring and summer.

Wang, J.; Muyzer, G.; Bodelier, P. L. E.; den Oudsten, F.; Laanbroek, H. J.

2009-04-01

328

Estimation of soil pH at Mount Beigu Wetland based on visible and near infrared reflectance spectroscopy  

NASA Astrophysics Data System (ADS)

pH of the wetland soil is one of the most important indicators for aquatic vegetation and water bodies. Mount Beigu Wetland, just near the Yangtse River, is under ecological recovery. Visible and near infrared reflectance spectroscopy was adopted to estimate soil pH of the wetland. The spectroradiometer, FieldSpec 3 (ASD) with a full spectral range (350-2500 nm), was used to acquire the reflectance spectra of wetland soil, and soil pH was measured with the pH meter of IQ150 (Spectrum) and InPro 3030 (Mettler Toledo). 146 soil samples were taken with soil sampler (Eijkelkamp) according to different position and depth, which covered the wider range of pH value from 7.1 to 8.39. 133 samples were used to establish the calibration model with the method of partial least square regression and principal component analysis regression. 13 soil samples were used to validate the model. The results show that the model is not good, but the mean error and root mean standard error of prediction are less (1.846% and 0.186 respectively). Spectral reflectancebased estimation of soil pH of the wetland is applicable and the calibration model needs to be improved.

Hu, Yongguang; Li, Pingping; Mao, Hanping; Chen, Bin; Wang, Xi

2006-12-01

329

Wetland extraction of Yancheng coastal area based on ALOS data  

NASA Astrophysics Data System (ADS)

Jiangsu coastal area is abundant in wetland resources and possesses wetland reserve of global relevancy. However, the wetland area has been shrinking with more and more human activities. In this paper, 5 ALOS AVNIR-2 images as well as an additional TM image acquired at low tide level were selected to carry out a research of Yancheng coastal wetland. Characteristics of subcategories and vegetation coverage were surveyed during filed work before a 2-tier decision tree method was adopted to distinguish different wetland categories. At last, the total area was classified as 8 major wetland categories with an overall accuracy of 97.16% as well as Kappa coefficient of 0.96. Only 2 sampling sites biased in the classification when 28 field recorded samples were compared and the result was satisfying.

Weng, Yongling; Fan, Xingwang; Tao, Jinmei

2010-09-01

330

Five years (2000-2004) of post-reconstruction monitoring of freshwater tidal wetlands in the urban Anacostia River, Washington, D.C. USA  

USGS Publications Warehouse

The Anacostia River in Washington, D.C. USA consisted of over 809 hectares (2000 acres) of freshwater tidal wetlands before mandatory dredging removed most of them in the first half of the 20th century. Much of this13 kilometer (8 mile) reach was transferred to the National Park Service (NPS). Planning processes in the 1980's envisioned a restoration (rejuvenation) of some wetlands for habitat, aesthetics, water quality and interpretative purposes. Subsequently, the U.S. Army Corps of Engineers in a cost share agreement with the District of Columbia reconstructed wetlands on NPS lands at Kenilworth - 12.5 hectares (1993), Kingman 27 hectares (2000), a Fringe Marsh - 6.5 hectares (2003) and is currently constructing Heritage Marsh - 2.5 hectares (2005/2006). The USGS Patuxent Wildlife Research Center in conjunction with the University of Maryland Biological Engineering Department was contracted to conduct post-reconstruction monitoring (2000-2004) to document the relative success and progress of the Kingman Marsh reconstruction primarily based on vegetative response but also in conjunction with seed bank and soil characteristics. Results from Kingman were compared to Kenilworth Marsh (reconstructed 7 years prior), Dueling Creek Marsh (last best remaining freshwater tidal wetland bench in the urbanized Anacostia watershed) and Patuxent River Marsh (in a more natural adjacent watershed). Vegetation establishment was initially strong at Kingman, but declined rapidly as measured by cover, richness, diversity, etc. under grazing pressure from resident Canada geese and associated reduction in sediment levels. This decline did not occur at the other wetlands. The decline occurred despite a substantial seed bank that was sustained primarily be water born propagules. Soil development, as true for most juvenile wetlands, was slow with almost no organic matter accumulation. By 2004 only two of 7 planted species remained (mostly Peltandra virginica) at Kingman which did provide almost 50% of the approximately 1/3 total vegetation cover remaining.

Hammerschlag, D.; Krafft, C.

2006-01-01

331

Pipeline corridors through wetlands -- Impacts on plant communities: Norris Brook Crossing Peabody, Massachusetts  

SciTech Connect

The goal of the Gas Research Institute Wetland Corridors Program is to document impacts of existing pipelines on the wetlands they traverse. To accomplish this goal, 12 existing wetland crossings were surveyed. These sites varied in elapsed time since pipeline construction, wetland type, pipeline installation techniques, and right-of-way (ROW) management practices. This report presents the results of a survey conducted August 17--19, 1992, at the Norris Brook crossing in the town of Peabody, Essex County, Massachusetts. The pipeline at this site was installed during September and October 1990. A backhoe was used to install the pipeline. The pipe was assembled on the adjacent upland and slid into the trench, after which the backhoe was used again to fill the trench and cover the pipeline. Within two years after pipeline construction, a dense vegetative community, composed predominantly of native perennial species, had become established on the ROW. Compared with adjacent natural areas undisturbed by pipeline installation, there was an increase in purple loosestrife and cattail within the ROW, while large woody species were excluded from the ROW. As a result of the ROW`s presence, habitat diversity, edge-type habitat, and species diversity increased within the site. Crooked-stem aster, Aster prenanthoides (a species on the Massasschusetts list of plants of special concern), occurred in low numbers in the adjacent natural areas and had reinvaded the ROW in low numbers.

Shem, L.M.; Van Dyke, G.D.; Zimmerman, R.E. [Argonne National Lab., IL (United States)

1994-12-01

332

An Inundated Wetlands Earth System Data Record: Global Monitoring of Wetland Extent and Dynamics  

NASA Astrophysics Data System (ADS)

Wetlands exert major impacts on global biogeochemistry, hydrology, and biological diversity. The extent and seasonal, interannual, and decadal variation of inundated wetlands play key roles in ecosystem dynamics. Despite the importance of these environments in the global cycling of carbon and water and to current and future climate, the extent and dynamics of global wetlands remain poorly characterized and modeled. This is primarily because of the scarcity of suitable regional-to-global remote-sensing data for characterizing wetland distribution and dynamics. As part of a NASA MEaSUREs project, we are constructing a global-scale Earth System Data Record (ESDR) of inundated wetlands to facilitate investigations on their role in climate, biogeochemistry, hydrology, and biodiversity. The ESDR is being generated using legacy algorithms developed from spaceborne remote sensing data sets and is comprised of two complementary components. The first are fine resolution (100 m) maps of wetland extent, vegetation type, and seasonal inundation dynamics, derived from Synthetic Aperture Radar (SAR), for continental-scale areas covering crucial wetland regions. The second are global monthly maps of inundation extent at ~25 km resolution for the period 1992- 2009, derived from multiple satellite observations. We present details of the ESDR construction including remote sensing algorithm applications, cross-product harmonization, and planned data set distribution. The status of current efforts to assemble this ESDR, including data processing, wetland classifications, and open water change mappings derived from L-band data for the state of Alaska and select basins in Eurasia are presented. This ESDR will provide the first accurate, consistent and comprehensive global-scale data set of wetland inundation and vegetation, including continental-scale multitemporal and multi-year monthly inundation dynamics at multiple scales. Portions of this work were carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

Podest, E.; McDonald, K.; Chapman, B.; Hess, L.; Moghaddam, M.; Kimball, J. S.; Matthews, E.; Prigent, C.

2008-12-01

333

FORT BELKNAP WETLANDS MANAGEMENT PROGRAM  

EPA Science Inventory

The product activities include: 1) Conducting wetland inventories and wetland assessments in the Milk River Watershed. This will include wetland delineations, and the collection of vascular plants and plant identification. Currently there is no baseline data of wetland activite...

334

Protect Your Wetlands  

NSDL National Science Digital Library

This resource explains how to create a wetlands awareness program and how to protect wetlands through the regulatory process. In addition, it explains the federal programs designed to protect wetlands and how to procure state and local protection for wetlands. It is part of a module that aims to help students get to know the complexities of wetlands, discover wildlife, enjoy the experience of being outdoors, and learn how necessary wetlands are to the health of our environment. For educators and their middle school students, it suggests ways to study wetland characteristics, why wetlands are important, and how students and teachers can help protect a local wetland in any part of the country. An associated set of activities is also available.

335

Wonderful Wetlands: An Environmental Education Curriculum Guide for Wetlands.  

ERIC Educational Resources Information Center

This curriculum guide was designed to give teachers, students, and society a better understanding of wetlands in the hope that they learn why wetlands should be valued and preserved. It explores what is meant by wetlands, functions and values of wetlands, wetland activities, and wetland offerings which benefit animal and plant life, recreation,…

King County Parks Div., Redmond, WA.

336

Wetlands and Fish: A Vital Connection 2 What is a Wetland? 3  

E-print Network

#12;Wetlands and Fish: A Vital Connection 2 What is a Wetland? 3 Are Wetlands Important? 4 Wetlands and their Surroundings 5 Wetlands in the U.S. Caribbean Region 6 Distribution 6 Common Wetland Types 7 Saltwater wetlands 7 Freshwater wetlands 7 Wetland Loss and Consequences 9 Fish Need Wetlands 10 Wetlands as Habitat 10

337

A compound method for automatically extracting plateau wetlands from satellite imagery  

NASA Astrophysics Data System (ADS)

Timely information on wetland distribution can be effectively acquired by means of remote sensing. A Landsat TM image recorded on 17 July 2009 (row: 36; column: 134) at a spatial resolution of 30 m was used to map wetlands in Maduo County of northwestern Qinghai Province with a combined method of thresholding, tassled cap transformation and vegetation indexing. The wetlands found in the study area fall into two broad types, I and II. Type I wetlands are characterized by a close proximity to water bodies. Type II wetlands are characterized by a higher vegetative component that obscures their morphology. Thresholding was used to map type I wetlands from TM5. Tasseled Cap transformation was used to map type II wetlands. With the assistance of NDVI, snow was then removed, leaving only grassland and type II wetland to be separate. Type 1 wetland was mapped at 832 km2. The second type of wetland was mapped at 422.97 km2. A total of 1254.97 km2 wetlands were mapped. Comparison with the raw color composite of the same image reveals that the mapping has been accomplished quite accuracy. More research will be undertaken to compare the classified results with those obtained with supervised and unsupervised results. Both thresholding and Tassled cap transformation are found to be effective at detecting different types of wetlands in the plateau environment

Li, Huan; Gao, Jay

2012-10-01

338

Canada's Wetland Habitats  

NSDL National Science Digital Library

This detailed information on the wetlands of Canada begins with an introduction defining wetlands and their locations along with details about their value and human and biological threats. The second chapter provides a summary of the Canadian wetland classification system with descriptions on the five classes of wetlands which are bogs, fens, swamps, marshes, and shallow open water. Chapter three gives an opportunity to explore the seven major wetland regions in Canada, which are classified as arctic, subarctic, boreal, prairie, temperate, oceanic, and mountain. The Ramsar internatioinal convention on wetlands and Canadian Ramsar sites are outlined in the last chapter.

339

Freshwater Wetlands: A Citizen's Primer.  

ERIC Educational Resources Information Center

The purpose of this "primer" for the general public is to describe the general characteristics of wetlands and how wetland alteration adversely affects the well-being of humans. Particular emphasis is placed on wetlands in New York State and the northeast. Topics discussed include wetland values, destruction of wetlands, the costs of wetland

Catskill Center for Conservation and Development, Inc., Hobart, NY.

340

Experiences with constructed wetland systems in Korea  

NASA Astrophysics Data System (ADS)

In spite of the low temperature during the winter season and the high land environment, the wetland treatment system is gaining popularity in Korea because of its lower construction cost and simplicity in operation and maintenance. Many different types of wetland treatment systems have been built during the last 10 years, among which the free water surface wetland has been predominant. Most of the large-scale systems are government projects for improving the water quality of the streams flowing into the estuary dikes and reservoirs. The covering plants used in this system are different in different areas but cattails and reeds or their combinations are common. Constructed wetlands in Korea can be characterized by their shallow depths and short hydraulic residence times. There is no established flow pattern and configuration rules for constructing wetlands, but many efforts have been made with a view to improving their ecological function. Flow control is the most difficult problem in designing a riverbed or riparian wetland. There have been scores of flow rate control devices developed for wetlands, but none of them guarantee wetlands’ safety against flooding. In earlier wetland construction, the building materials were mainly soil. Recently, strong and durable building materials such as rocks, gravel beds, concrete and steel are used at vulnerable places to protect them from erosion. Our investigation indicated that the wetland system would be an appropriate technology because it is not only cheaper to construct, but also requires less maintenance work. However, we suffer from the reduced effectiveness in performance during the winter. We need to evaluate the partial treatment accomplished during 6 to 7 months per year.

Youngchul, Kim; Gilson, Hwang; Jin-Woo, Lee; Je-Chul, Park; Dong-Sup, Kim; Min-Gi, Kang; in-Soung, Chang

2006-10-01

341

Impacts of water development on aquatic macroinvertebrates, amphibians, and plants in wetlands of a semi-arid landscape  

USGS Publications Warehouse

We compared the macroinvertebrate and amphibian communities of 12 excavated and 12 natural wetlands in western North Dakota, USA, to assess the effects of artificially lengthened hydroperiods on the biotic communities of wetlands in this semi-arid region. Excavated wetlands were largely unvegetated or contained submergent and deep-marsh plant species. The natural wetlands had two well-defined vegetative zones populated by plant species typical of wet meadows and shallow marshes. Excavated wetlands had a richer aquatic macroinvertebrate community that included several predatory taxa not found in natural wetlands. Taxa adapted to the short hydroperiods of seasonal wetlands were largely absent from excavated wetlands. The amphibian community of natural and excavated wetlands included the boreal chorus frog, northern leopard frog, plains spadefoot, Woodhouse's toad, and tiger salamander. The plains spadefoot occurred only in natural wetlands while tiger salamanders occurred in all 12 excavated wetlands and only one natural wetland. Boreal chorus frogs and northern leopard frogs were present in both wetland types; however, they successfully reproduced only in wetlands lacking tiger salamanders. Artificially extending the hydroperiod of wetlands by excavation has greatly influenced the composition of native biotic communities adapted to the naturally short hydroperiods of wetlands in this semi-arid region. The compositional change of the biotic communities can be related to hydrological changes and biotic interactions, especially predation, related to excavation.

Euliss, N. H., Jr.; Mushet, D. M.

2004-01-01

342

Ecological effects of pipeline construction through deciduous forested wetlands, Midland County, Michigan. Topical report, October 1990--August 1992  

SciTech Connect

This study is designed to record vegetational changes induced by the construction of a large-diameter gas pipeline through deciduous forested wetlands. Two second-growth wetland sites mapped Lenawee soils were selected in Midland County, Michigan: Site 1, a younger stand subjected to recent selective logging, and Site 2, a more mature stand. The collection of ecological data to analyze plant succession on the right-of-way (ROW) and the effects of the developing ROW plant communities on adjacent forest communities was initiated in 1989. Cover class estimates were made for understory and ROW plant species on the basis of 1 {times} 1{minus}m quadrats. Individual stem diameters and species counts were recorded for overstory plants in 10{minus}m quadrats. Although long-term studies have not been completed, firm baseline data were established for comparative analyses with future sampling. Current data indicate that vegetation became well-established on the ROW within one year and subsequently increased in coverage. About 65% of the species were wetland indicators, and the dominants included seeded and natural invading species; nevertheless, some elements of the original flora regenerated and persist. The plants of the ecotone understories of both sites changed from their original composition as a result of the installation of the gas pipeline. Although some forest species persist at both sites, the ecotone of Site I was influenced more by the seeded species, whereas the natural invaders were more important at Site 2.

Rastorfer, J.R. [Chicago State Univ., IL (United States). Dept. of Biological Sciences; Van Dyke, G.D.; Zellmer, S.D.; Wilkey, P.L. [Argonne National Lab., IL (United States)

1995-04-01

343

Constructing a Baseline Model of Alpine Wetlands of the Uinta Mountains, Utah, USA  

NASA Astrophysics Data System (ADS)

Alpine wetlands of the Uinta Mountains, northeastern Utah, contain a variety of groundwater-dependent ecosystems. Unlike their counterparts in other areas of the Rocky Mountains, these systems have been relatively unstudied. The Reader Lakes area on the southern slope of the range was selected for detailed study because of its variety of wetland plant communities, homogenous bedrock geology, and minimal human impact. The primary goal of this interdisciplinary study is to establish the functional links between the geomorphology and hydrogeology of these high mountain wetlands and their constituent plant communities. In addition to traditional field studies and water chemistry, geospatial technologies are being used to organize and analyze both field data (water chemistry and wetland vegetation) and archived multispectral imagery (2006 NAIP images). The hydrology of these wetlands is dominated by groundwater discharge and their surface is dominated by string-and-flark morphology of various spatial scales, making these montane wetlands classic patterned fens. The drainage basin is organized into a series of large-scale stair-stepping wetlands, bounded by glacial moraines at their lower end. Wetlands are compartmentalized by a series of large strings (roughly perpendicular to the axial stream) and flarks. This pattern may be related to small ridges on the underlying ground moraine and possibly modified by beaver activity along the axial stream. Small-scale patterning occurs along the margins of the wetlands and in sloping-fen settings. The smaller-scale strings and flarks form a complex; self-regulating system in which water retention is enhanced and surface flow is minimized. Major plant communities have been identified within the wetlands for example: a Salix planifolia community associated with the peaty strings; Carex aquatilis, Carex limosa, and Eriophorum angustifolium communities associated with flarks; as well as a Sphagnum sp.- rich hummocky transition zone between wetland and non-wetland areas. On-going analyses of water-chemistry data will be used to identify discrete water sources and to characterize the degree of horizontal and vertical water mixing within the system, as well as to help identify the biochemical requirements of the different plant communities. Results indicate that the chemical composition of the main creek reflects the accumulative effect that the peaty flarks have on the creek as it passes through the wetland system, with pH overall decreasing from 7.3 to 7.0, dissolved oxygen decreasing from 9400 to 8400 micrograms per liter and total dissolved solids increasing from 9 mg/L to 13 mg/L. String ground water is characterized by relatively high pH (ranging from 6.0 to 7.1), high oxidizing-reducing potential (ORP) (ranging from 50 mV to 180 mV), high dissolved oxygen (from 2500 ?g/L to 9600 ?g /L) while flark ground water has relatively lower pH (5.6 to 6.8), low oxidizing reducing potential (ORP) (ranging from -66 mV to 150 mV), low dissolved oxygen (from 900 ?g /L to 9000 ?g /L).

Matyjasik, M.; Ford, R. L.; Bartholomew, L. M.; Welsh, S. B.; Hernandez, M.; Koerner, D.; Muir, M.

2008-12-01

344

How the Energy and Water Development Appropriations Act of 1993 has impacted the constitutional dynamics of federal wetlands delineation and regulation  

SciTech Connect

A reliable source of specific criteria for recognizing a wetland, as defined for regulatory purposes would be valuable. In 1987 the Army Corps of Engineers developed a technical manual for identifying wetlands (1987 Wetlands Manual). An interagency manual (1989 Wetlands Manual) was later developed. This manual has been used to identify wetlands according to three evidentiary factors: vegetation, hydrology, and soil. This paper addresses the development of criteria to delineate wetlands, and describes some of the logic used by federal courts to uphold the limited constitutional use of the 1989 Wetlands Manual.

Johnson, J.J.S.; Logan, W.L.

1995-12-31

345

Decomposition rates and phosphorus concentrations of purple Loosestrife ( Lythrum salicaria ) and Cattail ( Typha spp.) in fourteen Minnesota wetlands  

Microsoft Academic Search

Purple Loosestrife is rapidly displacing native vegetation in North American wetlands. Associated changes in wetland plant\\u000a communities are well understood. Effects of Loosestrife invasion on nutrient cycling and decomposition rates in affected wetlands\\u000a are unknown, though potentially of significance to wetland function. We used litter bag methods to quantify decomposition\\u000a rates and phosphorus concentrations of purple Loosestrife (Lythrum salicaria) and

Sarah L. Emery; James A. Perry

1996-01-01

346

Threats to Wetlands  

NSDL National Science Digital Library

This resource presents a history of wetland loss and describes how wetlands are lost. It also stresses the consequences of wetland loss including flooding, loss of wildlife habitat, and declining water quality. The site is part of a module that aims to help students get to know the complexities of wetlands, discover wildlife, enjoy the experience of being outdoors, and learn how necessary wetlands are to the health of our environment. For educators and their middle school students, it suggests ways to study wetland characteristics, why wetlands are important, and how students and teachers can help protect a local wetland in any part of the country. An associated set of activities is also available.

347

Investigating Neighborhood Wetlands  

NSDL National Science Digital Library

This activity is field investigation where students map a neighborhood wetland and generate various watershed questions. Students identify engineered structures in or around this wetland and consider how flood water can be controlled.

Tim Shulstad, Lincoln Elementary School, Alexandria, MN, based on The Nature of Science and Engineering, an original activity created by Molly Stoddard, Prairie Wetlands Learning Center, Fergus Falls, MN.

348

LUMCON 2011 Summer Program Wetland Vegetation  

E-print Network

for satisfactory work. A grade of "A" indicates distinguished mastery of the course material; a grade of "B" good mastery; a grade of "C" acceptable mastery. A grade of "D" indicates minimally acceptable achievement

Nyman, John

349

Warm season grass establishment on limestone-amended coal slurry  

SciTech Connect

Direct seeding of limestone amended areas can be an effective alternative to soil covering. Both wetland and upland plant communities have been established on post law (PL 95-87) slurry areas by the Wildlife Research Laboratory of Southern Illinois University at Carbondale. Terrestrial habitat reclamation has emphasized both cool and warm season grass species, using a 3-year program of limestone amendment (40-50 tons/acre/year) and cover crop (years 1 and 2) and perennial grass (year 3) establishment. Warm season grasses have been included in Midwest slurry reclamation projects since 1984. Vegetation monitoring of three Midwest sites (Illinois and Kentucky), ranging in age from 3 to 12 years since planting, identified current ground cover in excess of 100 percent. Warm season grasses accounted for 48 to 73 percent of the ground cover. Switchgrass (Panicum virgatum) was the dominant warm season species at all sites, with vegetative cover values ranging from 48 to more than 56 percent. Indiangrass (Sorghastrum nutans) accounted for 12 to 16 percent of the ground cover at the two Kentucky sites 3 years after establishment. Vegetative density for all species (forbs and grasses) ranged from 539 to 622 stems/m{sup 2} while above ground biomass values ranged from 404 to over 900 gm/m{sup 2}. Warm season grass establishment practices on these direct seeded slurry areas have been successful in providing excellent ground cover and diverse upland wildlife habitat.

Nawrot, J.R.; Skeel, V.A. [Southern Illinois Univ., Carbondale, IL (United States); Gray, B. [Peabody Coal Company, Graham, KY (United States); Newton, R.

1997-12-31

350

California Wetlands Information System  

NSDL National Science Digital Library

Comprehensive wetlands information to the general public, the educational community, and government agencies. Though much of the information is California-specific, there is an abundance of location-independent information available. Topics covered include restoration and mitigation, wetlands policy, vernal pools, and the role the state agencies play in wetlands conservation. Site features many links to external resources. The "What's new" section features all the latest California wetlands news and research.

351

National Wetlands Inventory (NWI)  

NSDL National Science Digital Library

The National Wetlands Inventory of the U.S. Fish and Wildlife Service provides information on the characteristics, extent, and status of U.S. wetlands and deepwater habitats. In addition to status and trends reports, this site contains publications, including manuals, plant and hydric soils lists, field guides, posters, wall size resource maps, atlases, state reports, and articles published in professional journals. The site also contains wetland maps and digital data, a kids and educators section, and a wetlands interactive mapper tool.

352

Relating groundwater to seasonal wetlands in southeastern Wisconsin, USA  

USGS Publications Warehouse

Historically, drier types of wetlands have been difficult to characterize and are not well researched. Nonetheless, they are considered to reflect the precipitation history with little, if any, regard for possible relation to groundwater. Two seasonal coastal wetland types (wet prairie, sedge meadow) were investigated during three growing seasons at three sites in the Lake Michigan Basin, Wisconsin, USA. The six seasonal wetlands were characterized using standard soil and vegetation techniques and groundwater measurements from the shallow and deep systems. They all met wetland hydrology criteria (e.g., water within 30 cm of land surface for 5% of the growing season) during the early portion of the growing season despite the lack of appreciable regional groundwater discharge into the wetland root zones. Although root-zone duration analyses did not fit a lognormal distribution previously noted in groundwater-dominated wetlands, they were able to discriminate between the plant communities and showed that wet prairie communities had shorter durations of continuous soil saturation than sedge meadow communities. These results demonstrate that the relative rates of groundwater outflows can be important for wetland hydrology and resulting wetland type. Thus, regional stresses to the shallow groundwater system such as pumping or low Great Lake levels can be expected to affect even drier wetland types. ?? Springer-Verlag 2008.

Skalbeck, J.D.; Reed, D.M.; Hunt, R.J.; Lambert, J.D.

2009-01-01

353

Freshwater Wetland dynamics in South Kingstown, Rhode Island, 1939 1972  

NASA Astrophysics Data System (ADS)

The extent and causes of changes in the fresh-water wetlands of South Kingstown, Rhode Island were determined through field work and through the analysis of panchromatic aerial photographs taken in 1939 and 1972. During this period, there was a net loss of 0.9 percent of the total area (2345.2 ha) of wetland present in 1939. Highway construction and residential development accounted for most of this loss. Approximately 17 percent of the wetland present in 1939 had changed sufficiently by 1972 to warrant reclassification. Plant succession alone accounted for 57 percent of the changes in wetland types, while man's activities were influential in 41 percent of the cases. Ninety-two percent of the natural changes in wetland types was progressive, while 58 percent of the changes induced by man and undetermined causes was retrogressive. Man's major role was to alter the water regimes and vegetation of wetlands. There was a decrease in wetland diversity as the most abundant type, wooded swamp, grew in area while the abundance of shallow marshes, meadows, and shrub swamps declined. A knowledge of wetland dynamics is essential in the management of wetlands for a diversity of wildlife and other natural values.

Golet, Francis C.; Parkhurst, James A.

1981-05-01

354

Wetlands: An Interdisciplinary Exploration  

ERIC Educational Resources Information Center

The topic of wetlands provides a rich context for curriculum integration. This unit contains seven activities that integrate environmental science with math, technology, social studies, language arts, and other disciplines. In this series, students will identify plants and animals found in wetlands, understand the function of wetlands through the…

Czerniak, Charlene M.

2004-01-01

355

EPA Wetlands Education  

NSDL National Science Digital Library

The Wetlands Education site contains everything teachers need to help students understand wetlands and how they fit into the water cycle and the environment. The site offers links to activities, curricula and instructor guides, education programs, resources and teaching tools to assist teachers in wetlands and habitat education.

356

Wetlands, Wildlife, and People.  

ERIC Educational Resources Information Center

Discusses the problems created when wetlands are drained or altered by humans. Provides a brief case study of the Everglades as an example of the effects of human intervention. Presents four learning activities (along with reproducible worksheets) that deal with the benefits of wetlands, and some debated issues over wetlands. (TW)

Naturescope, 1986

1986-01-01

357

Are isolated wetlands isolated?  

USGS Publications Warehouse

While federal regulations during the past 10 years have treated isolated wetlands as unconnected to aquatic resources protected by the Clean Water Act, they provide critical ecosystem services to society that extend well beyond their wetland boundaries. The authors offer well-documented examples from the scientific literature on some of the ecosystem services provided by isolated wetlands to society and other ecosystems.

Smith, Loren M.; Euliss, Ned H.; Haukos, David A.

2011-01-01

358

Fish assemblages, connectivity, and habitat rehabilitation in a diked Great Lakes coastal wetland complex  

USGS Publications Warehouse

Fish and plant assemblages in the highly modified Crane Creek coastal wetland complex of Lake Erie were sampled to characterize their spatial and seasonal patterns and to examine the implications of the hydrologic connection of diked wetland units to Lake Erie. Fyke netting captured 52 species and an abundance of fish in the Lake Erie–connected wetlands, but fewer than half of those species and much lower numbers and total masses of fish were captured in diked wetland units. Although all wetland units were immediately adjacent to Lake Erie, there were also pronounced differences in water quality and wetland vegetation between the hydrologically isolated and lake-connected wetlands. Large seasonal variations in fish assemblage composition and biomass were observed in connected wetland units but not in disconnected units. Reestablishment of hydrologic connectivity in diked wetland units would allow coastal Lake Erie fish to use these vegetated habitats seasonally, although connectivity does appear to pose some risks, such as the expansion of invasive plants and localized reductions in water quality. Periodic isolation and drawdown of the diked units could still be used to mimic intermediate levels of disturbance and manage invasive wetland vegetation.

Kowalski, Kurt P.; Wiley, Michael J.; Wilcox, Douglas A.

2014-01-01

359

Ecological outcomes and evaluation of success in passively restored southeastern depressional wetlands.  

SciTech Connect

Abstract: Depressional wetlands may be restored passively by disrupting prior drainage to recover original hydrology and relying on natural revegetation. Restored hydrology selects for wetland vegetation; however, depression geomorphology constrains the achievable hydroperiod, and plant communities are influenced by hydroperiod and available species pools. Such constraints can complicate assessments of restoration success. Sixteen drained depressions in South Carolina, USA, were restored experimentally by forest clearing and ditch plugging for potential crediting to a mitigation bank. Depressions were assigned to alternate revegetation methods representing desired targets of herbaceous and wet-forest communities. After five years, restoration progress and revegetation methods were evaluated. Restored hydroperiods differed among wetlands, but all sites developed diverse vegetation of native wetland species. Vegetation traits were influenced by hydroperiod and the effects of early drought, rather than by revegetation method. For mitigation banking, individual wetlands were assessed for improvement from pre-restoration condition and similarity to assigned reference type. Most wetlands met goals to increase hydroperiod, herb-species dominance, and wetland-plant composition. Fewer wetlands achieved equivalence to reference types because some vegetation targets were incompatible with depression hydroperiods and improbable without intensive management. The results illustrated a paradox in judging success when vegetation goals may be unsuited to system constraints.

De Steven, Diane; Sharitz, Rebecca R.; Barton, Christopher, D.

2010-11-01

360

Effect of litter, leaf cover and cover of basal internodes of the dominant species Molinia caerulea on seedling recruitment and established vegetation  

Microsoft Academic Search

The effects of litter removal, leaf cover of established plants and cover of basal internodes of a dominant species Molinia caerulea on seedling germination and the dynamics of established plants were studied in a field experiment in an oligotrophic wet meadow. Although the negative influence of litter on total seedling number and seedling species composition was non-significant, litter significantly affected

Jan Lepš

2005-01-01

361

Wetlands Reserve Program  

NSDL National Science Digital Library

Recognizing that the health of the nation's wetlands depends on the fate of private (as well as public-owned) wetlands, the Wetlands Reserve Program is an important, voluntary initiative led by the USDA Natural Resources Conservation Service (NRCS) to provide "technical and financial support" to help private landowners restore their wetlands. This straightforward site describes the Wetlands Reserve Program (WRP), including a map showing national WRP acreage, several question/ answer fact sheets, state programs and contacts, and a slide show (PowerPoint) entitled Producing Wildlife Habitat Results. Although the site targets the general public, students and educators will find it useful and instructive.

362

Seed Rain of Restored and Natural Prairie Wetlands  

Microsoft Academic Search

In prairie wetland restorations, seeds may be limiting plant recolonization but this has never been quantified in the field.\\u000a We evaluated the seed rain in restored and natural wetlands to determine if seed limitation constrains plant recolonization.\\u000a We were particularly interested in determining whether Carex species, dominant vegetation of seasonally flooded zones, are seed limited in restorations. We quantified seed

Karin M. Kettenring; Susan M. Galatowitsch

2011-01-01

363

Does harvesting sustain plant diversity in central Mexican wetlands?  

Microsoft Academic Search

In Central México, wetland plants are harvested for weaving, fodder, and fertilizer. To test whether harvesting alters plant\\u000a diversity, we compared the effects of harvesting all vegetation once, follow-up harvesting of Typha domingensis Pers. one or three more times, and a non-harvested control, using two sites differing in water depth in an annually burned\\u000a wetland near Morelia, México. After one

Steven J. Hall; Roberto Lindig-Cisneros; Joy B. Zedler

2008-01-01

364

Wetlands of the Magellanic Steppe (Tierra Del Fuego, Argentina)  

Microsoft Academic Search

Our main objective was to classify vegetation and soils of wetlands in northern Tierra del Fuego (Argentina) along a latitudinal\\u000a precipitation gradient within the Magellanic Steppe Zone. We presented the first detailed ecological characterization of these\\u000a wetlands by relating floristic composition to local site conditions, bedrock and climate. The survey consisted of 125 phytosociological\\u000a censuses and 52 soil profile descriptions.

Marta B. Collantes; Juan A. Anchorena; Susana Stoffella; Celina Escartín; Ruth Rauber

2009-01-01

365

Factors affecting waterfowl use of constructed wetlands in northwestern Minnesota  

Microsoft Academic Search

Waterfowl pair and brood use of constructed wetlands was evaluated during 1980–81 on 4 Wildlife Management Areas in northwestern\\u000a Minnesota. Weekly ground counts of waterfowl were made at each of 109 wetlands during the April to mid-July nesting season\\u000a and correlated with physical, vegetative, and limnological characteristics. The number of pairs of the 10 most common waterfowl\\u000a species using the

Douglas A. Leschisin; Gary L. Williams; Milton W. Weller

1992-01-01

366

Effects of wetland excavation on avian communities in eastern Washington  

Microsoft Academic Search

Despite having an arid climate, the Columbia River Basin of eastern Washington is one of the most important areas for breeding,\\u000a migrating, and wintering wetland birds in the Pacific Northwest. Extensive farmland irrigation near the O’Sullivan Reservoir\\u000a and other areas has raised water tables, resulting in closed canopies of emergent vegetation in what are now permanent, shallow\\u000a wetlands. During 1994–95,

Janean H. Creighton; Rodney D. Sayler; James E. Tabor; Matthew J. Monda

1997-01-01

367

1997 Monitoring report for the Gunnison, Colorado Wetlands Mitigation Plan  

SciTech Connect

Under the Uranium Mill Tailings Remedial Action (UMTRA) Project, the U.S. Department of Energy (DOE) cleaned up uranium mill tailings and other surface contamination near the town of Gunnison, Colorado. Remedial action resulted in the elimination of 4.3 acres (ac) (1.7 hectares [ha]) of wetlands. This loss is mitigated by the enhancement of six spring-fed areas on Bureau of Land Management (BLM) land (mitigation sites). Approximately 254 ac (1 03.3 ha) were fenced at the six sites to exclude grazing livestock. Of the 254 ac (103.3 ha), 17.8 ac (7.2 ha) are riparian plant communities; the rest are sagebrush communities. Baseline grazed conditions of the riparian plant communities at the mitigation sites were measured prior to fencing. This report discusses results of the fourth year of a monitoring program implemented to document the response of vegetation and wildlife to the exclusion of livestock. Three criteria for determining success of the mitigation were established: plant height, vegetation density (bare ground), and vegetation diversity. By 1996, Prospector Spring, Upper Long`s Gulch, and Camp Kettle met the criteria. The DOE requested transfer of these sites to BLM for long-term oversight. The 1997 evaluation of the three remaining sites, discussed in this report, showed two sites (Houston Gulch and Lower Long`s Gulch) meet the criteria. The DOE will request the transfer of these two sites to the BLM for long-term oversight. The last remaining site, Sage Hen Spring, has met only two of the criteria (percent bare ground and plant height). The third criterion, vegetation diversity, was not met. The vegetation appears to be changing from predominantly wet species to drier upland species, although the reason for this change is uncertain. It may be due to below-normal precipitation in recent years, diversion of water from the spring to the stock tank, or manipulation of the hydrology farther up gradient.

NONE

1997-11-01

368

Exploring Policy Options to Stop the Loss of Wetlands on Prairie Landscapes  

NASA Astrophysics Data System (ADS)

Wetlands from the prairie pothole region of North America have been disappearing at rapid rates over the past century. Within Canada, the issue of wetland loss is compounded by the lack of high resolution wetland inventories, the lack of information on rates of wetland loss, and the absence of wetland policies to further protect against loss. In Alberta, the situation is particularly problematic as increasing development pressures continue to place wetlands at risk. The 'no net loss' of wetlands policy established in 1993 has been ineffective, as wetland loss has continued, leaving Albertans searching for alternative policy options. An alternative policy option is to shift focus from wetland area to wetland function. We present a wetland function assessment system founded on ecological and hydrological processes for estimating wetland functions, including biodiversity, flood control, and pollution reduction, for a regional watershed in Alberta. First, we establish wetland loss rates using inventory time series from 1960 to present; wetland loss estimates can be derived from a break in slope in the area-frequency relationship. Second, we create a high-resolution wetland inventory using a novel approach that fuses LiDAR data (probability of wetland) with aerial photographs (to distinguish open water and the surrounding wet meadow zone). Third, using this wetland inventory, we identify indicators of wetland function using GIS and remote sensing data and technologies for application at regional watershed scales. Biodiversity indicators include a wetland's condition, ability to provide habitat, and potential for high ecological diversity. Flood control indicators include a wetland's ability to store water, connect to surface drainage network, and desynchronize flood waves throughout the landscape. Pollution control indicators include a wetland's contributing source area of nutrients, mechanisms that transport nutrients to the wetland, and mechanisms that retain nutrients once in the wetland. Finally, the function indicators are aggregated to provide an overall function score for each wetland. This overall value estimates a wetland's potential to provide ecosystem services compared to other wetlands on the landscape. The function indicators in combination with 'scarcity' as indicated by the historical wetland loss rates allows policy makers to adjust thresholds between wetland function scores and policy and management objectives. The wetland function assessment system offers a scientific foundation upon which wetland policy can be built. To exemplify its policy potential, we conduct quantitative ';future' scenarios to determine priority wetlands for protection under different development scenarios - this scenario analysis reveals the necessity of making tradeoffs among wetland functions, as wetlands with high ecological function may not be the same wetlands with high hydrological function. The project's resulting wetland function assessment system will improve conservation and restoration/remediation efforts by identifying high functioning wetlands, by revealing the necessity of tradeoffs, and by directing conservation towards preserving wetlands that provide important ecosystem services while allowing other wetlands to be developed.

Serran, J.; Creed, I. F.

2013-12-01

369

Using Landsat MSS data with soils information to identify wetland habitats  

NASA Technical Reports Server (NTRS)

A previous study showed that certain fresh water wetland vegetation types can be spectrally separated when a maximum likelihood classification procedure is applied to Landsat spectral data. However, wetland and upland types which have similar vegetative life forms (e.g., upland hardwoods and hardwood swamps) are often confused because of spectral similarity. Therefore, the current investigation attempts to differentiate similar wetland and upland types by combining Landsat multispectral scanner (MSS) data with soils information. The Pigeon River area in northern Indiana used in the earlier study was also employed in this investigation. A layered classification algorithm which combined soils and spectral data was used to generate a wetland classification. The results of the spectral/soils wetland classification are compared to the previous classification that had been based on spectral data alone. The results indicate wetland habitat mapping can be improved by combining soils and other ancillary data with Landsat spectral data.

Ernst, C. L.; Hoffer, R. M.

1981-01-01

370

Climate and site management as driving factors for the atmospheric greenhouse gas exchange of a restored wetland  

NASA Astrophysics Data System (ADS)

The full atmospheric greenhouse gas (GHG) budget of a restored wetland in Western Denmark could be established for the years 2009-2011 from eddy covariance measurements of carbon dioxide (CO2) and methane (CH4) fluxes. The water table in the wetland, being restored in 2002, was unregulated, and the vegetation height was limited through occasional grazing by cattle and grass cutting. The annual net CO2 uptake varied between 195 and 983 g m-2 and the annual net CH4 release varied between 11 and 17 g m-2. In all three years the wetland was a carbon sink and removed between 42 and 259 g C m-2 from the atmosphere. However, in terms of the annual GHG budget (assuming that 1 g CH4 is equivalent to 25 g CO2 with respect to the greenhouse effect) the wetland was a sink in 2009, a source in 2010 and neutral in 2011. Complementary observations of meteorological factors and management activities were used to explain the large inter-annual variations in the full atmospheric GHG budget of the wetland. It is shown that the largest impacts on the annual GHG fluxes, eventually defining their sign, came from site management through changes in grazing duration and animal stocking density and from extreme weather patterns through an unusually long period of snow cover in the second year of observations. Since integrated CO2 and CH4 flux data from restored wetlands are still very rare, it is concluded that more long-term flux measurements are needed to predict the role of this land use type in the atmospheric GHG budget more accurately.

Herbst, M.; Friborg, T.; Schelde, K.; Jensen, R.; Ringgaard, R.; Thomsen, A. G.; Soegaard, H.

2012-07-01

371

Synthesis of soil-plant correspondence data from twelve wetland studies throughout the United States  

USGS Publications Warehouse

This report synthesizes the information collected for the U.S. Fish and Wildlife Service in a series of 12 studies designed to describe the relation between soils and vegetation in wetlands located in 11 States throughout the United States. Results of the study demonstrated almost complete agreement between hydric soils and hydrophytic vegetation. However, agreement between nonhydric soils and nonhydric vegetation was not as high because most nonhydric soils lay adjacent to the wetland boundary. There was some evidence that various vegetation layers describe the hydrophytic nature of the vegetation differently than others. Herbaceous species seem to reflect current hydrologic conditions while trees may reflect past hydrologic conditions. Wetland indicator categories for some plants listed in the Fish and Wildlife Service national list of plant species that occur in wetlands may need to be reevaluated as additional data become available. Similarly, soils listed in the Soil Conservation Service hydric soils of the United States list should always be verified in the field prior to assigning them to a hydric category. While wetland hydrology is the critical factor determining wetlands, the use of soils and vegetation are frequently adequate for designating wetland conditions.

Segelquist, C.A.; Slauson, W.L.; Scott, M.L.; Auble, Gregor T.

1990-01-01

372

Annual monitoring report for the Gunnison, Colorado, wetlands mitigation plan  

SciTech Connect

The US Department of Energy (DOE) administers the Uranium Mill Tailings Remedial Action (UMTRA) Project to clean up uranium mill tailings and other surface contamination at 24 abandoned uranium mill sites in 10 states. One of these abandoned mill sites is near the town of Gunnison, Colorado; surface remediation and the environmental impacts of remedial action are described in the Gunnison environmental assessment (EA) (DOE, 1992). Remedial action resulted in the elimination of 4.3 acres (ac) 1.7 hectares (ha) of wetlands and mitigation of this loss of wetlands is being accomplished through the enhance of 18.4 ac (7.5 ha) of riparian plant communities in six spring feed areas on Bureau of Land Management (BLM) land. The description of the impacted and mitigation wetlands is provided in the Mitigation and Monitoring Plan for Impacted Wetlands at the Gunnison UMTRA Project Site, Gunnison, Colorado (DOE, 1994), which is attached to the US Army corps of Engineers (USACE) Section 404 Permit. As part of the wetlands mitigation plan, the six mitigation wetlands were fenced in the fall of 1993 to exclude livestock grazing. Baseline of grazed conditions of the wetlands vegetation was determined during the summer of 1993 (DOE, 1994). A 5-year monitoring program of these six sites has been implemented to document the response of vegetation and wildlife to the exclusion of livestock. This annual monitoring report provides the results of the first year of the 5-year monitoring period.

NONE

1995-10-01

373

Hurricane-induced failure of low salinity wetlands.  

PubMed

During the 2005 hurricane season, the storm surge and wave field associated with Hurricanes Katrina and Rita eroded 527 km(2) of wetlands within the Louisiana coastal plain. Low salinity wetlands were preferentially eroded, while higher salinity wetlands remained robust and largely unchanged. Here we highlight geotechnical differences between the soil profiles of high and low salinity regimes, which are controlled by vegetation and result in differential erosion. In low salinity wetlands, a weak zone (shear strength 500-1450 Pa) was observed approximately 30 cm below the marsh surface, coinciding with the base of rooting. High salinity wetlands had no such zone (shear strengths > 4500 Pa) and contained deeper rooting. Storm waves during Hurricane Katrina produced shear stresses between 425-3600 Pa, sufficient to cause widespread erosion of the low salinity wetlands. Vegetation in low salinity marshes is subject to shallower rooting and is susceptible to erosion during large magnitude storms; these conditions may be exacerbated by low inorganic sediment content and high nutrient inputs. The dramatic difference in resiliency of fresh versus more saline marshes suggests that the introduction of freshwater to marshes as part of restoration efforts may therefore weaken existing wetlands rendering them vulnerable to hurricanes. PMID:20660777

Howes, Nick C; FitzGerald, Duncan M; Hughes, Zoe J; Georgiou, Ioannis Y; Kulp, Mark A; Miner, Michael D; Smith, Jane M; Barras, John A

2010-08-10

374

Ecosystem attributes related to tidal wetland effects on water quality.  

PubMed

Biogeochemical functioning of ecosystems is central to nutrient cycling, carbon balance, and several ecosystem services, yet it is not always clear why levels of function might vary among systems. Wetlands are widely recognized for their ability to alter concentrations of solutes and particles as water moves through them, but we have only general expectations for what attributes of wetlands are linked to variability in these processes. We examined changes in several water quality variables (dissolved oxygen, dissolved organic carbon, nutrients, and suspended particles) to ascertain which constituents are influenced during tidal exchange with a range of 17 tidal freshwater wetlands along the Hudson River, New York, USA. Many of the constituents showed significant differences among wetlands or between flooding and ebbing tidal concentrations, indicating wetland-mediated effects. For dissolved oxygen, the presence of even small proportional cover by submerged aquatic vegetation increased the concentration of dissolved oxygen in water returned to the main channel following a daytime tidal exchange. Nitrate concentrations showed consistent declines during ebbing tides, but the magnitude of decline varied greatly among sites. The proportional cover by graminoid-dominated high intertidal vegetation accounted for over 40% of the variation in nitrate decline. Knowing which water-quality alterations are associated with which attributes helps suggest underlying mechanisms and identifies what functions might be susceptible to change as sea level rise or salinity intrusion drives shifts in wetland vegetation cover. PMID:23600246

Findlay, S; Fischer, D

2013-01-01

375

Fate of viruses in artificial wetlands.  

PubMed

Little is known about the ability of wetlands to remove disease-causing viruses from municipal wastewater. In this study we examined the survival of several indicators of viral pollution (indigenous F-specific bacteriophages, seeded MS2 bacteriophage, and seeded human poliovirus type 1) applied in primary municipal wastewater to artificial wetland ecosystems. Only about 1% of the indigenous F-specific RNA bacteriophages survived flow through the vegetated wetland beds at a 5-cm-day-1 hydraulic application rate during the period from June through December 1985. The total number of indigenous F-specific bacteriophages (F-specific RNA and F-specific DNA phages) was also reduced by about 99% by wetland treatment, with the mean inflow concentration over the period of an entire year reduced from 3,129 to 33 PFU ml-1 in the outflow of a vegetated bed and to 174 PFU ml-1 in the outflow of an unvegetated bed. Such superior treatment by the vegetated bed demonstrates the significant role of higher aquatic plants in the removal process. Seeded MS2 bacteriophage and seeded poliovirus were removed more efficiently than were the indigenous bacteriophages, with less than 0.2% of MS2 and 0.1% of the poliovirus surviving flow at the same hydraulic application rate. The decay rate (k) of MS2 in a stagnant wetlands (k = 0.012 to 0.028 h-1) was lower than that for flowing systems (k = 0.44 to 0.052 h-1), reflecting the enhanced capacity for filtration or adsorption of viruses by the root-substrate complex (and associated biofilm).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3034155

Gersberg, R M; Lyon, S R; Brenner, R; Elkins, B V

1987-04-01

376

Fate of viruses in artificial wetlands.  

PubMed Central

Little is known about the ability of wetlands to remove disease-causing viruses from municipal wastewater. In this study we examined the survival of several indicators of viral pollution (indigenous F-specific bacteriophages, seeded MS2 bacteriophage, and seeded human poliovirus type 1) applied in primary municipal wastewater to artificial wetland ecosystems. Only about 1% of the indigenous F-specific RNA bacteriophages survived flow through the vegetated wetland beds at a 5-cm-day-1 hydraulic application rate during the period from June through December 1985. The total number of indigenous F-specific bacteriophages (F-specific RNA and F-specific DNA phages) was also reduced by about 99% by wetland treatment, with the mean inflow concentration over the period of an entire year reduced from 3,129 to 33 PFU ml-1 in the outflow of a vegetated bed and to 174 PFU ml-1 in the outflow of an unvegetated bed. Such superior treatment by the vegetated bed demonstrates the significant role of higher aquatic plants in the removal process. Seeded MS2 bacteriophage and seeded poliovirus were removed more efficiently than were the indigenous bacteriophages, with less than 0.2% of MS2 and 0.1% of the poliovirus surviving flow at the same hydraulic application rate. The decay rate (k) of MS2 in a stagnant wetlands (k = 0.012 to 0.028 h-1) was lower than that for flowing systems (k = 0.44 to 0.052 h-1), reflecting the enhanced capacity for filtration or adsorption of viruses by the root-substrate complex (and associated biofilm).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3034155

Gersberg, R M; Lyon, S R; Brenner, R; Elkins, B V

1987-01-01

377

Creating Wildlife Habitat with Native Florida Freshwater Wetland Plants1  

E-print Network

CIR 912 Creating Wildlife Habitat with Native Florida Freshwater Wetland Plants1 Martin B. Main by establishing and managing desirable native plants. Native wetland plants play important ecological roles many more species than non-native plants because native wildlife evolved with native plant communities

Watson, Craig A.

378

Characterisation of the hydrology of an estuarine wetland  

Microsoft Academic Search

The intertidal zone of estuarine wetlands is characterised by a transition from a saline marine environment to a freshwater environment with increasing distance from tidal streams. An experimental site has been established in an area of mangrove and salt marsh wetland in the Hunter River estuary, Australia, to characterise and provide data for a model of intertidal zone hydrology. The

Catherine E Hughes; Philip Binning; Garry R Willgoose

1998-01-01

379

Conservative and reactive solute transport in constructed wetlands  

Microsoft Academic Search

The transport of bromide, a conservative tracer, and rhodamine WT (RWT), a photodegrading tracer, was evaluated in three wastewater-dependent wetlands near Phoenix, Arizona, using a solute transport model with transient storage. Coupled sodium bromide and RWT tracer tests were performed to establish conservative transport and reactive parameters in constructed wetlands with water losses ranging from (1) relatively impermeable (15%), (2)

Steffanie H. Keefe; Larry B. Barber; Robert L. Runkel; Joseph N. Ryan; Diane M. McKnight; Roland D. Wass

2004-01-01

380

Wetlands in Changed Landscapes: The Influence of Habitat Transformation on the Physico-Chemistry of Temporary Depression Wetlands  

PubMed Central

Temporary wetlands dominate the wet season landscape of temperate, semi-arid and arid regions, yet, other than their direct loss to development and agriculture, little information exists on how remaining wetlands have been altered by anthropogenic conversion of surrounding landscapes. This study investigates relationships between the extent and type of habitat transformation around temporary wetlands and their water column physico-chemical characteristics. A set of 90 isolated depression wetlands (seasonally inundated) occurring on coastal plains of the south-western Cape mediterranean-climate region of South Africa was sampled during the winter/spring wet season of 2007. Wetlands were sampled across habitat transformation gradients according to the areal cover of agriculture, urban development and alien invasive vegetation within 100 and 500 m radii of each wetland edge. We hypothesized that the principal drivers of physico-chemical conditions in these wetlands (e.g. soil properties, basin morphology) are altered by habitat transformation. Multivariate multiple regression analyses (distance-based Redundancy Analysis) indicated significant associations between wetland physico-chemistry and habitat transformation (overall transformation within 100 and 500 m, alien vegetation cover within 100 and 500 m, urban cover within 100 m); although for significant regressions the amount of variation explained was very low (range: ?2 to ?5.5%), relative to that explained by purely spatio-temporal factors (range: ?35.5 to ?43%). The nature of the relationships between each type of transformation in the landscape and individual physico-chemical variables in wetlands were further explored with univariate multiple regressions. Results suggest that conservation of relatively narrow (?100 m) buffer strips around temporary wetlands is likely to be effective in the maintenance of natural conditions in terms of physico-chemical water quality. PMID:24533161

Bird, Matthew S.; Day, Jenny A.

2014-01-01

381

Removal of metals in constructed wetlands  

SciTech Connect

Trace metals are difficult to remove from municipal wastewater by conventional wastewater treatment methods. Constructed wetlands have the potential to trap and remove metals from the water column. Long term removal is expected to occur by accumulation and burial in the plant detritus in a manner similar to the removal of phosphorus. Few data are available in the literature on removal of metals by constructed wetlands. A free water surface constructed wetland at Sacramento Regional Wastewater Treatment Plant treating secondary municipal effluent has been operating since the spring of 1994. Removal data for 13 metals are presented for the period from August 1994 to May 1995. About 3,785 m{sup 3}/d (1 mgd) of pure oxygen activated sludge effluent, disinfected using UV light, is further treated through a 8 ha (20 acre) constructed wetlands Ten separate, parallel treatment cells are available to demonstrate the effects of detention time, vegetation management, and application frequency on the removal of metals, organics and ammonia. Detention time can be varied from 3 to 13 days by varying the flow and the water depth. The vegetation, primarily bulrush with some cattails, will be managed by different techniques to minimize mosquito production. Application frequency varies from continuous flow to batch flow (1 to 2 days of loading with 1 day of discharge).

Crites, R.W.; Watson, R.C.; Williams, C.R.

1996-12-31

382

Recognizing Wetlands An Informational Pamphlet  

E-print Network

Recognizing Wetlands An Informational Pamphlet What is a Wetland? The US Army Corps of Engineers(Corps) and the US Environmental Protection Agency define wetlands as follows: Those areas that are inundated conditions. Wetlands generally include swamps, marshes, bogs, and similar areas. Wetlands are areas

US Army Corps of Engineers

383

Wetland Loss and Biodiversity Conservation  

Microsoft Academic Search

Most species of wetland-dependent organisms live in multiple local populations sustained through occasional migration. Retention of minimum wetland densities in human-dominated landscapes is funda- mental to conserving these organisms. An analysis of wetland mosaics was performed for two regions of the northeastern United States to assess the degree to which historical wetland loss alters the metrics of wetland mosaics and

James P. Gibbs

2000-01-01

384

Evaluation of surface water dynamics for water-food security in seasonal wetlands, north-central Namibia  

NASA Astrophysics Data System (ADS)

Agricultural use of wetlands is important for food security in various regions. However, land-use changes in wetland areas could alter the water cycle and the ecosystem. To conserve the water environments of wetlands, care is needed when introducing new cropping systems. This study is the first attempt to evaluate the water dynamics in the case of the introduction of rice-millet mixed-cropping systems to the Cuvelai system seasonal wetlands (CSSWs) in north-central Namibia. We first investigated seasonal changes in surface water coverage by using satellite remote sensing data. We also assessed the effect of the introduction of rice-millet mixed-cropping systems on evapotranspiration in the CSSWs region. For the former investigation, we used MODIS and AMSR-E satellite remote sensing data. These data showed that at the beginning of the wet season, surface water appears from the southern (lower) part and then expands to the northern (higher) part of the CSSWs. For the latter investigation, we used data obtained by the classical Bowen ratio-energy balance (BREB) method at an experimental field site established in September 2012 on the Ogongo campus, University of Namibia. This analysis showed the importance of water and vegetation conditions when introducing mixed-cropping to the region.

Hiyama, T.; Suzuki, T.; Hanamura, M.; Mizuochi, H.; Kambatuku, J. R.; Niipele, J. N.; Fujioka, Y.; Ohta, T.; Iijima, M.

2014-09-01

385

Response of ducks to glyphosate-induced habitat alterations in wetlands  

Microsoft Academic Search

The effects of glyphosate herbicide-induced changes in wetland emergent vegetation (largely cattails,Typha spp.) on densities of ducks (Anatinae) were assessed in northeastern North Dakota. In 1990 and 1991, 17 cattail-dominated\\u000a wetlands were randomly assigned to 0% (reference wetlands), 50%, 70%, or 90% areal spray coverages with glyphosate herbicide.\\u000a Densities of green-winged teal (Anas crecca), bluewinged teal (Anas discors), gadwalls (Anas

George M. Linz; Dage C. Blixt; David L. Bergman; William J. Bleier

1996-01-01

386

Tools for Carex revegetation in freshwater wetlands: understanding dormancy loss and germination temperature requirements  

Microsoft Academic Search

Carex is a globally distributed genus with more than 2000 species worldwide and Carex species are the characteristic vegetation of sedge meadow wetlands. In the mid-continental United States, Carex species are dominant in natural freshwater wetlands yet are slow to recolonize hydrologically restored wetlands. To aid in\\u000a Carex revegetation efforts, we determined the dormancy breaking and temperature germination requirements of

Karin M. Kettenring; Susan M. Galatowitsch

2007-01-01

387

Space-based detection of wetlands' surface water level changes from L-band SAR interferometry  

Microsoft Academic Search

Interferometric processing of JERS-1 L-band Synthetic Aperture Radar (SAR) data acquired over south Florida during 1993–1996 reveals detectable surface changes in the Everglades wetlands. Although our study is limited to south Florida it has implication for other large-scale wetlands, because south Florida wetlands have diverse vegetation types and both managed and natural flow environments. Our analysis reveals that interferometric coherence

Shimon Wdowinski; Sang-Wan Kim; Falk Amelung; Timothy H. Dixon; Fernando Miralles-Wilhelm; Roy Sonenshein

2008-01-01

388

Ecological Threats and Agricultural Opportunities of the Aquatic Cane-Like Grass Phragmites australis in Wetlands  

Microsoft Academic Search

\\u000a Wetlands are some of the most biologically productive and dynamic natural ecosystems with multiple value for man and nature.\\u000a Indeed wetlands provide goods and service such as water storing, floodwater trapping, and trapping of sediment and pollutants.\\u000a Wetlands also affect climate change by absorbing CO2,?storing and releasing heat, and harnessing sunlight using a rich variety of vegetation that supports animal

Andreas P. Mamolos; Anna E. Nikolaidou; Athina K. Pavlatou-Ve; Sofia K. Kostopoulou; Kiriaki L. Kalburtji

389

Macrophyte growth in a pilot-scale constructed wetland for industrial wastewater treatment  

Microsoft Academic Search

A pilot-scale wetland was constructed to assess the feasibility of treating the wastewater from a tool industry in Santo Tomé, Santa Fe, Argentina. The wastewater had high conductivity and pH, and contained Cr, Ni and Zn. This paper describes the growth of vegetation in the experimental wetland and the nutrient and metal removal.The wetland was 6×3×0.4m. Water discharge was 1000ld?1

H. R. Hadad; M. A. Maine; C. A. Bonetto

2006-01-01

390

Wetlands Assessment for site characterization, Advanced Neutron Source (ANS)  

SciTech Connect

This Wetlands Assessment has been prepared in accordance with the Department of Energy`s (DOE) Code of Federal Regulations (CFR) 10 CFR 1022, Compliance with Floodplain/Wetlands Environmental Review Requirements, which established the policy and procedure for implementing Executive Order 11990, Protection of Wetlands. The proposed action is to conduct characterization activities in or near wetlands at the ANS site. The proposed action will covered under a Categorical Exclusion, therefore this assessment is being prepared as a separate document [10 CFR 1022.12(c)]. The purpose of this Wetlands Assessment is to fulfill the requirements of 10 CFR 1022.12(a) by describing the project, discussing the effects of the proposed action upon the wetlands, and considering alternatives to the proposed action.

Wade, M.C.; Socolof, M.L. [Oak Ridge National Lab., TN (United States). Energy Div.; Rosensteel, B.; Awl, D. [JAYCOR, Vienna, VA (United States)

1994-10-01

391

Influence of beaver impoundments on vegetative composition, and modeling habitat suitability as a tool for wildlife management and conservation.  

E-print Network

??Beavers (Castor canadensis) can have dramatic effects on vegetative communities through impounding streams and wetlands. These alterations may influence rare plant species where beaver create… (more)

Bonner, Jerri LeAnne.

2005-01-01

392

Use of triacylglycerol profiles established by high performance liquid chromatography with ultraviolet-visible detection to predict the botanical origin of vegetable oils.  

PubMed

A method for the determination of triacylglycerols (TAGs) in vegetable oils from different botanical origins by HPLC with UV-vis detection has been developed. Using a core-shell particle packed column (C18, 2.6 ?m), TAG separation was optimized in terms of mobile phase composition and column temperature. Using isocratic elution with acetonitrile/n-pentanol at 10 °C, excellent efficiency with good resolution between most of the TAG peak pairs, within a total analysis time of 15 min, was achieved. Using mass spectrometry detection, a total of 15 peaks, which were common to oils of six different botanical origins (corn, extra virgin olive, grapeseed, hazelnut, peanut and soybean) were identified. These peaks were used to construct linear discriminant analysis (LDA) models for botanical origin prediction. Ratios of the peak areas selected by pairs were used as predictors. All the oils were correctly classified with assignment probabilities higher than 95%. PMID:21855883

Lerma-García, M J; Lusardi, R; Chiavaro, E; Cerretani, L; Bendini, A; Ramis-Ramos, G; Simó-Alfonso, E F

2011-10-21

393

Use of macroinvertebrates to identify cultivated wetlands in the Prairie Pothole Region  

USGS Publications Warehouse

We evaluated the use of macroinvertebrates as a potential tool to identify dry and intensively farmed temporary and seasonal wetlands in the Prairie Pothole Region. The techniques we designed and evaluated used the dried remains of invertebrates or their egg banks in soils as indicators of wetlands. For both the dried remains of invertebrates and their egg banks, we weighted each taxon according to its affinity for wetlands or uplands. Our study clearly demonstrated that shells, exoskeletons, head capsules, eggs, and other remains of macroinvertebrates can be used to identify wetlands, even when they are dry, intensively farmed, and difficult to identify as wetlands using standard criteria (i.e., hydrology, hydrophytic vegetation, and hydric soils). Although both dried remains and egg banks identified wetlands, the combination was more useful, especially for identifying drained or filled wetlands. We also evaluated the use of coarse taxonomic groupings to stimulate use of the technique by nonspecialists and obtained satisfactory results in most situations.

Euliss, N.H., Jr.; Mushet, D.M.; Johnson, D.H.

2001-01-01

394

Symbiont nitrogenase, alder growth, and soil nitrate response to phosphorus addition in alder ( Alnus incana ssp. rugosa) wetlands of the Adirondack Mountains, New York State, USA  

Microsoft Academic Search

Speckled alder (Alnus incana ssp. rugosa) is a characteristic species of scrub-shrub 1-type wetlands, the second most common wetland type in major watersheds of the Adirondack Mountains in New York State. Speckled alder is an actinorhizal nitrogen fixer that relies heavily on N2 over soil N and fixes substantial amounts of nitrogen in wetlands, resulting in little vegetation processing of

Kemal Gökkaya; Todd M. Hurd; Dudley J. Raynal

2006-01-01

395

The ecological value of constructed wetlands for treating urban runoff.  

PubMed

The Sweetwater Authority's urban runoff diversion system (URDS) comprises constructed wetlands on a hillside between the town of Spring Valley and the Sweetwater Reservoir, California, USA. The URDS were designed to divert dry-weather and first-flush urban runoff flows from the Sweetwater reservoir. However, these constructed wetlands have developed into ecologically valuable habitat. This paper evaluates the following ecological questions related to the URDS: (1) the natural development of the species present and their growth pattern; (2) the biodiversity and pollutant stress on the plants and invertebrates; and (3) the question of habitat provided for endangered species. The URDS wetlands are comprised primarily of rush (Scirpus spp.) and cattails (Typha spp.). This vegetative cover ranged from 39-78% of the area of the individual wetland ponds. Current analyses of plant tissues and wetland sediment indicates the importance of sediment sorption for metals and plant uptake of nutrients. Analyses of URDS water following runoff events show the URDS wetlands do reduce the amount of nutrients and metals in the water column. Invertebrate surveys of the wetland ponds revealed lower habitat quality and environmental stress compared to unpolluted natural habitat. The value of the wetlands as wildlife habitat is constrained by low plant biodiversity and pollution stress from the runoff. Since the primary Sweetwater Authority goal is to maintain good water quality for drinking, any secondary utilization of URDS habitat by species (endangered or otherwise) is deemed an added benefit. PMID:17410841

Pankratz, S; Young, T; Cuevas-Arellano-, H; Kumar, R; Ambrose, R F; Suffet, I H

2007-01-01

396

Vulnerability of Northern Prairie Wetlands to Climate Change  

NSDL National Science Digital Library

This peer reviewed article from Bioscience journal is on the effect of climate change on northern prairie wetlands. The prairie pothole region (PPR) lies in the heart of North America and contains millions of glacially formed, depressional wetlands embedded in a landscape matrix of natural grassland and agriculture. These wetlands provide valuable ecosystem services and produce 50% to 80% of the continent's ducks. We explored the broad spatial and temporal patterns across the PPR between climate and wetland water levels and vegetation by applying a wetland simulation model (WETSIM) to 18 stations with 95-year weather records. Simulations suggest that the most productive habitat for breeding waterfowl would shift under a drier climate from the center of the PPR (the Dakotas and southeastern Saskatchewan) to the wetter eastern and northern fringes, areas currently less productive or where most wetlands have been drained. Unless these wetlands are protected and restored, there is little insurance for waterfowl against future climate warming. WETSIM can assist wetland managers in allocating restoration dollars in an uncertain climate future

W. CARTER JOHNSON, BRUCE V. MILLETT, TAGIR GILMANOV, RICHARD A. VOLDSETH, GLENN R. GUNTENSPERGEN, and DAVID E. NAUGLE (;)

2005-11-01

397

Agricultural Encroachment: Implications for Carbon Sequestration in Tropical African Wetlands  

NASA Astrophysics Data System (ADS)

Tropical wetlands have been shown to exhibit high rates of net primary productivity and may therefore play an important role in global climate change mitigation through carbon assimilation and sequestration. Many permanently flooded areas of tropical East Africa are dominated by the highly productive C4 emergent macrophyte sedge, Cyperus papyrus L. (papyrus). However, increasing population densities around wetland margins in East Africa are reducing the extent of papyrus coverage due to the planting of subsistence crops such as Cocoyam (Colocasia esculenta). We have assessed the impact of this land use change on the carbon cycle in theis wetland environment. Eddy covariance techniques were used, on a campaign basis, to measure fluxes of carbon dioxide over both papyrus and cocoyam dominated wetlands located on the Ugandan shore of Lake Victoria. The integration of flux data over the annual cycle shows that papyrus wetlands have the potential to act as a sink for significant amounts of carbon, in the region of 10 t C ha-1 yr-1. The cocoyam vegetation was found to assimilate ~7 t C ha-1 yr-1 but when carbon exports from crop biomass removal were taken into account these wetlands represent a significant net loss of carbon of similar magnitude. The development of sustainable wetland management strategies are therefore required in order to promote the dual wetland function of crop production and the mitigation of greenhouse gas emissions especially under future climate change scenarios.

Jones, M. B.; Saunders, M.; Kansiime, F.

2013-12-01

398

The establishment and management of emergent vegetation in sewage-fed artificial marshes and the effects of these marshes on water quality  

Microsoft Academic Search

Experiments on the establishment and harvest ofPhragmites\\u000a australis,Zizania\\u000a aquatica,Typha\\u000a latifolia,Typha\\u000a angustifolia,Sparganium\\u000a eurycarpum andSpartina\\u000a pectinata were conducted in three 0.4 ha clay-bottomed man-made marshes in the central portion of the lower peninsula of Michigan.\\u000a Propagules consisted of seeds for the annualZ. aquatica and root and rhizome clumps for the other species.S. eurycarpum showed rapid establishment but was subject to invasion by

Karl E. Ulrich; Thomas M. Burton

1984-01-01

399

Using aquatic invertebrates to delineate seasonal and temporary wetlands in the Prairie Pothole Region of North America  

USGS Publications Warehouse

Tillage can destroy or greatly disturb indicators of hydric soils and hydrophytic vegetation, making delineation of tilled wetlands difficult. The remains of aquatic invertebrates (e.g., shells, drought-resistant eggs, and trichopteran cases) are easily identifiable and persist in wetland substrates even when wetlands are dry. Additionally, these remains are not easily destroyed by mechanical tillage. To test the feasibility of using invertebrate remains to delineate wetlands, we used two methods to identify the wetland edge of ten seasonal and ten temporary wetlands, evenly divided between grassland and cropland landscapes. First, we identified the wetland edge using hydric soil and vegetation indicators along six evenly spaced transects in each wetland (our standard delineation). We then identified the wetland edge along the same transects using aquatic invertebrate remains as our indicator. In grassland landscapes, delineations of the wetland edge made using invertebrate remains were consistently at the same location or closer to the wetland center as the standard delineations for both seasonal and temporary wetlands. In cropland landscapes, however, many of our invertebrate delineations of seasonal and temporary wetlands were on the upland side of our standard delineations. We attribute the differences to movement of remains during tillage, increased maximum pool levels in cropland wetlands, and disturbance of hydric soils and plants. We found that the elevations of the wetland edge indicated by invertebrate remains were more consistent within a wetland than elevations determined by standard delineations. Aquatic invertebrate remains can be useful in delineating wetlands when other indicators have been destroyed or severely disturbed by tillage.

Euliss, N.H., Jr.; Mushet, D.M.; Johnson, D.H.

2002-01-01

400

Nutrient removal in constructed microcosm wetlands for treating polluted river water in northern China  

Microsoft Academic Search

River water pollution is increasingly widespread in northern China and can lead to problems with the drinking water for the residents if not properly treated. Constructed wetlands are a promising solution and have become increasingly popular in China. In this study the nutrient removal and plant uptake in constructed microcosm wetlands vegetated with Typha orientalis, Phragmites australis, Scirpus validus and

Haiming Wu; Jian Zhang; Peizhi Li; Jinyong Zhang; Huijun Xie; Bo Zhang

2011-01-01

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