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Wetlands are habitats with highly variable species composition, hydrology and functioning in terms of energy exchange and forming of local climate. We compared two graminoid temperate wetlands situated nearby and at similar latitude to see how much their temperature characteristics differed with changing conditions during a growing season. The results showed that the two habitats, a littoral zone of a fishpond and a wet meadow, differed markedly. The daily means at 2 m were on average higher in the littoral as a consequence of lower temperature minima in the wet meadow. However, the daily maxima at 2 m were higher in the wet meadow due to advection of warm air from the surrounding habitats. We suppose that the temperature of the air at 2 m was predominantly influenced by temperature characteristics of the surrounding habitats (i.e. local meteorology). The temperature within vegetation and at the soil surface was dependent on the soil water content. This relation was stronger in the wet meadow than in the littoral due to the complex microtopography of the latter Carex dominated habitat. Vegetation played an important role in influencing temperature at the soil surface and within the vegetation cover, i.e. in the very proximity of the land surface. Because of the higher LAI, this trend was stronger in the wet meadow. [ABSTRACT FROM AUTHOR]

This article presents an evaluation of two sampling methods for assessing the biodiversity of heavily vegetated wetlands. The aim was to establish an effective sampling regime to maximise total taxon richness and minimise sampling effort. Three Integrated Constructed Wetland (ICW) systems in Annetown Valley, Co. Waterford, SE of the Republic of Ireland, were sampled during spring and summer 2005. The two methods that were evaluated were pond netting and two types of horizontal activity traps, namely ˵horizontal activity traps″ (HATs) and modified ˵horizontal activity traps″ (modified HATs). The activity traps provided a one-way funnel system and were constructed from 2 l plastic bottles, allowing for the passive collection of taxa. HATs were designed to capture macroinvertebrates in open water and modified HATs, which were designed specifically for this study, were used to sample within stands of dense emergent vegetation. Results show that a combination of pond netting and activity traps will yield a more complete estimate of taxon richness. The performance of Modified HATs was not significantly different from that of the HATs in dense vegetation. Tests on the sampling effort required for each method are also discussed. [ABSTRACT FROM AUTHOR]

Aquaculture or the production of aquatic organisms (both flora and fauna) under controlled conditions has been practiced for centuries, primarily for the generation of food, fiber, and fertilizer. The water hyacinth and a host of other organisms like duckweed, seaweed, midge larvae, and alligator weeds are used for wastewater treatment. Water hyacinth system, wetland system, evapotranspiration system, rapid rate filtration, slow rate system, overland flow system, and subsurface infiltration have also been applied. This chapter describes the above applications and explains their practice, limitations, design criteria, performance, and costs. [ABSTRACT FROM AUTHOR]

A five-year study of vegetation succession was commenced following construction of a new electric transmission right-of-way (ROW) through a wooded wetland in Sussex County, Delaware, USA. In response to restrictions imposed by regulatory agencies that have declared only selective clearing of targeted incompatible tall-growing trees, with the retention of existing compatible low-growing trees and shrubs, is permitted for new ROW construction, this study investigates a comparison of clear and selective cutting methods. Prior to ROW establishment permanent quadrats were installed to evaluate the vegetation communities that followed clear-cut and select-cut tree removal. Integrated Vegetation Management (IVM) techniques were used as secondary interventions and compared against control sites. Baseline data were gathered and changes were documented for species numbers, diversity, stem count, and relative importance (RIV). The management of desirable ROW species and their relative wildlife use (WUI) are considered. Results show that IVM interventions stimulated vegetation succession from a mature wooded wetland to a low shrub/herbaceous community as successfully in the clear-cut as in the select-cut quadrats. Total numbers of species reflect that the loss of trees was later substituted by a twofold increase in the number of herbaceous species (RIV > 1). Shrub species = numbers remained relatively stable. The environmental effects of electric transmission ROW establishment and various vegetation management techniques upon plant species succession in wetlands are discussed. [ABSTRACT FROM AUTHOR]

Wetland management by the Eastern Habitat Joint Venture (EHJV) has focused primarily on water level control to increase the amount of available brood-rearing habitat for waterfowl along the Saint John River floodplain in New Brunswick. Impounded wetlands make up approximately 13% of the Saint John River Floodplain complex. Study objectives included an evaluation of waterfowl brood, and wetland obligate bird use of impoundments and seasonally flooded wetlands within the Saint John River floodplain. Historical water level data and a GIS wetlands inventory were used to estimate the duration of flooding on seasonally flooded wetland habitats, and the distribution and relative amount of brood-rearing habitat throughout the breeding period by region. Aerial brood surveys and call response surveys were used to estimate the relative abundance of waterfowl broods and breeding wetland obligate birds respectively. The overall density of waterfowl broods was greater on impoundments than on seasonally flooded wetlands during both years of study but varied by site. Mean species richness of wetland obligate birds was significantly greater on impoundments than on seasonally flooded wetland habitat. Generally, use of seasonally flooded wetlands by wetland obligate birds during late summer declined while the use of impoundments increased. Current habitat management for waterfowl appears to be compatible with habitat requirements of wetland obligate birds by increasing the availability of interspersed open water and emergent vegetation throughout the breeding season. A watershed-based analysis of wetland habitat suggests future wetland management should focus on enhancing current impoundments within the Saint John River floodplain. Resources must be secured for maintenance and water level manipulation within existing managed wetlands rather than the construction of additional impoundments. Further evaluation of the distribution of wetland habitat types in the province is essential to identifying focus areas for waterbird conservation throughout NB. [ABSTRACT FROM AUTHOR]