Man-made Wetlands Research Articles

Nestedness and successional trajectories of macroinvertebrate assemblages in man-made wetlands

Current successional models, primarily those based on floral succession, propose several distinct trajectories based on the integration of two key hypotheses from succession theory: convergence versus divergence in species composition among successional sites, and progression towards versus deviation from a desired reference state. We applied this framework to faunal succession, including differential colonization between active and passive dispersers, and the nested patterns generated as a consequence of this peculiarity. Nine man-made wetlands located in three different areas, from 0-3 years from wetland creation, were assessed. In addition, 91 wetlands distributed throughout the region were used as references for natural macroinvertebrate communities. We predicted the following: (1) highly nested structures in pioneering assemblages will decrease to lower mid-term values due to a shift from active pioneering taxa to passive disperser ones; (2) passive idiosyncratic taxa will elicit divergent successional trajectories among areas; (3) the divergent trajectories will provoke lower local and higher regional diversity values in the mid-term assemblages than in pioneer assemblages. Our results were largely congruent with hypotheses (1) and (2), diverging from the anticipated patterns only in the case of the temporary wetlands area. However, overall diversity trends based on hypothesis (3) did not follow the expected pattern. The divergent successional trajectories did not compensate for regional biodiversity losses that occurred as a consequence of pioneering colonizer decline over time. Consequently, we suggest reconsidering wetland construction for mitigation purposes within mid-term time frames (≤ 3 years). Wetlands may not offset, within this temporal scenario, regional biodiversity loss because the ecosystem may not support idiosyncratic taxa from natural wetlands.

군산시 인공습지의 기능평가 및 식생학적 가치평가 연구

This study was performed to assess functions of 10 man-made wetlands in Gunsan City, Jeollabuk Province by means of RAM (Rapid Assessment Method), a technique recommended by Ramsar Convention to appraise wetlands. The assessment of the wetlands value found Gunsan reservoir to have the highest function points while Bukchosan reservoir was estimated to have the lowest function among the wetlands surveyed. By detailed factors of valued 10 man-made wetland, the wetlands were found to function most favorably in terms of vegetational variety and as habitat for wild animals. They need to have more improved functions as habitats for fish and amphibians reptiles, for preservation and betterment of water quality as well as for supplement of underground water, though. From the assessment of vegetational naturalness of the surveyed reservoirs, Gunsan reservoir turned out to be the most favorable wetland from the viewpoint of vegetation science whereas, however, Anjeong wetland was rated as the lowest in the assessment of vegetational value due to simplicity in its vegetation and lots of dangers in its neighborhood threatening its vegetation and ecology. The assessment of vegetational values for Gunsan, Gongchang, Daewi, Bukchosan, Anjeong, Geumgul, Changan and Chuksan reservoirs showed the same orextremely similar results as RAM function assessment. Geumsan reservoir only, however, featured the opposite result.

How do early successional patterns in man-made wetlands differ between cold temperate and Mediterranean regions?

The early stages of succession in newly created wetlands should be impacted by the region in which the wetland is located, since climate may have filtered the dominant biological strategies of the taxa leading this process and may condition their dynamics. We studied the early successional patterns of macroinvertebrates within man made ponds, located in cold temperate (Scandinavian Peninsula) and Mediterranean regions (Iberian Peninsula), during the first three years following their creation. We predicted (1) non random subsets of the regional species pool (deterministic assembly) guiding the successional process in cold temperate wetlands, and random (stochastic) assembly in the Mediterranean region; (2) higher successional rates in Mediterranean ponds than in the cold temperate ponds, with contrary episodes of highest and lowest change throughout the year; and (3) a significant difference in the composition of biological traits between regions, due to the dominance of traits adapted to hydrological variability in the Mediterranean region. Hypotheses on community structure (1) and the composition of dominant biological traits (3) were mostly supported – deterministic assembly mechanisms in the cold temperate ponds and stochastic assembly in the Mediterranean ponds; and a dominance of different biological traits between regions, explained by the need to overcome hydrological disturbances in the Mediterranean ponds. The dynamics of succession (2) were explained by climatic factors in the cold temperate region but not in the Mediterranean ponds. We suggest that the intrinsic hydrological variability of Mediterranean lentic systems may be a major factor driving community changes in man-made wetlands in this region. In order to generalize the observed patterns, we performed a meta-analysis of the temporal trends of taxonomic distinctness parameters of other successional studies across a latitudinal gradient in Europe, which supported the differences we had observed between latitudinal extremes.

Phenology of Shorebird Migration in Western Kentucky

Staging areas along the coasts provide reliable food resources, and shorebirds may use the same stopover locations every year. However, shorebirds use sites opportunistically in the interior of North America because of the transient nature of many habitats. Little is known, however, about the use of wetlands by migrating shorebirds in many areas of the Mississippi Alluvial Valley (MAV), including Kentucky. During 2004 and 2005, we examined the phenology of migration by shorebirds using stopover habitats in Kentucky. From March to October, we surveyed shorebirds in each moist soil unit as well as at other natural and man-made wetlands at each wildlife management area. Species abundance was recorded a minimum of once every 10-day period. We observed 25 species and 12,307 individual shorebirds during our study, with Charadrius vociferous (Killdeer; n = 4134), Calidris melanotos (Pectoral Sandpiper; n = 2912), Calidris minutilla (Least Sandpiper; n = 1138), Tringa melanoleuca (Gmelin) (Greater Yellowlegs; n = 942), and Tringa flavipes (Lesser Yellowlegs; n = 911) being most abundant. We observed nearly 75% more shorebirds during fall migration than during spring migration, possibly because less suitable habitat is available in the fall and shorebirds concentrate in those areas. In addition, shorebird migration extended over a longer period in the fall than in the spring, a pattern that likely results because adults migrate earlier in the fall and juveniles migrate later. Our results provide additional evidence that the MAV provides important stopover habitat for many species of shorebirds during both spring and fall migration.

Integrated Modeling of Groundwater and Surface Water Interactions in a Manmade Wetland

A manmade pilot wetland in south Florida, the Everglades Nutrient Removal (ENR) project, was modeled with a physics-based integrated approach using WASH123D (Yeh et al. 2006). Storm water is routed into the treatment wetland for phosphorus removal by plant and sediment uptake. It overlies a highly permeable surficial groundwater aquifer. Strong surface water and groundwater interactions are a key component of the hydrologic processes. The site has extensive field measurement and monitoring tools that provide point scale and distributed data on surface water levels, groundwater levels, and the physical range of hydraulic parameters and hydrologic fluxes. Previous hydrologic and hydrodynamic modeling studies have treated seepage losses empirically by some simple regression equations and, only surface water flows are modeled in detail. Several years of operational data are available and were used in model historical matching and validation. The validity of a diffusion wave approximation for two-dimensional overland flow (in the region with very flat topography) was also tested. The uniqueness of this modeling study is notable for (1) the point scale and distributed comparison of model results with observed data; (2) model parameters based on available field test data; and (3) water flows in the study area include two-dimensional overland flow, hydraulic structures/levees, three-dimensional subsurface flow and one-dimensional canal flow and their interactions. This study demonstrates the need and the utility of a physics-based modeling approach for strong surface water and groundwater interactions.

Design and management of free water surface constructed wetlands to minimize mosquito production

Constructed wetland technology has broad applications for the treatment of many types of wastewaters and provides an ecological approach to mitigate the release of nutrients and toxic materials into the environment. However, design features, maintenance activities and the characteristics of the wastewater undergoing treatment contribute differentially to potential levels of mosquito production and, consequently, to threats to human and animal health from mosquito-borne pathogens. Of the variables typically considered when designing free-water surface constructed wetlands for the improvement of water quality of municipal and agricultural wastewaters, organic loading (i.e., biochemical oxygen demand, total suspended solids), nutrients (nitrogen and phosphorus), and the configuration and maintenance of emergent vegetation can have strong effects on mosquito production. The production of Culex vectors of encephalitides and filarial worms is directly related to loading rates of organic matter and bottom-up enrichment of larval mosquito resources and their interaction with design features and management practices that reduce the physical and biological factors causing mortality of immature mosquitoes. As loading rates of organic matter and nutrients decline, the diversity of mosquitoes produced by treatment wetlands tends to increase and the relative abundance of Anopheles species, which are capable of vectoring the causative agents of malaria, increases in temperate man-made wetlands. Habitat features and management practices that create intermittently inundated substrate can lead to the production of other mosquitoes (i.e., Aedes, Psorophora) with floodwater life histories. Constructed wetland technology is expected to play an increasing role in water treatment and reclamation in tropical and subtropical countries where virulent mosquito-borne pathogens already cause significant levels of morbidity and mortality.

군산시 주요 4개 인공습지의 식물상 및 생활형

According to previous research on evaluating vegetative value of wetland and RAM evaluation targeting the man-made wetland in Gunsan, Gunsan Reservoir and Gongchang Reservoir had been found to have satisfactory results while Anjeong Reservoir and Changan Reservoir had been found to have unsatisfactory results. Aimed at those reservoirs, a vegetation survey was conducted to analyze differences in terms of flora and growth habit. As for the flora, Gunsan Reservoir ranked first with 433 kinds of plants, followed by Gongchang Reservoir with 306, Changan Reservoir with 176 and Anjeong Reservoir with 167. As for specific plant species by floristic region, it was identified that Gunsan Reservoir had 18 species, larger than other wetlands and also, it had more species of naturalized plants than others. This phenomenon is related to various wetland environments resulted from wider area of Gunsan Reservoir. In the case of dormancy form, hemicryptophytes were mainly distributed in Gunsan Reservoir and Gongchang Reservoir while annual plants were mainly distributed in Anjeong Reservoir and Changan Reservoir with heavy disturbance.

Change in biological traits and community structure of macroinvertebrates through primary succession in a man-made Swedish wetland

AbstractWe investigated the successional development of a benthic macrofaunal community in Kalmar Damme, a man-made wetland in southeastern Sweden, over a 13-y period after construction (1997–2009). We assessed primary succession by monitoring changes in species composition, biological traits, and community structure. Predictable successional changes occurred, and the structure of the community was complex at the advanced phase. Three successional phases were observed, each with typifying species. At the advanced phase, dominant biological traits shifted to favor animals with longer life-cycle durations, aerial dispersal strategies, and certain feeding types (i.e., filter-feeders, fine sediment collectors, predators, and parasites). We selected the Coleoptera assemblage to represent the macroinvertebrate community in an evaluation of the extent to which man-made wetlands in different age classes ( 50 y). No significant differences in Coleoptera assemblages...

Abundance of Migratory and Wintering Geese in Relation to Vegetation Succession in Man-Made Wetlands: The Effects of Grazing Regimes

The man-made wetlands in young polders in The Netherlands are important stopover and wintering sites for geese. We studied trends in vegetation composition and goose density in two study areas. One was located in a nature reserve situated in a polder reclaimed from an estuary, the other in a reserve in a polder reclaimed from a freshwater lake. In the former we compared an area of spontaneous vegetation succession with a summer-grazed area. In the latter the effect of reed Phragmites australis cover and height on field selection of geese was studied in an area grazed year-round by cattle and horses. In both study areas the area of short grassland (reed cover about 1%, reed height <0.5 m) was found to be significantly positively related to the grazing density of cattle and horses. Migrating and wintering Greylag Geese Anser anser and Barnacle Geese Branta leucopsis preferred to feed on these extensive short grasslands. In the ungrazed part of the study site in the reclaimed estuarine area, there was an inverse relation between goose density and the ousting of pioneer species of saline habitats and short grasses by tall species such as Calamagrostis epigejos, Phragmites australis, tall herbs and shrubs. Summer grazing by cattle and horses at stocking rates of about 0.4 to 0.9 animals/ha, retarded the vegetation succession to some extent, which resulted in a goose density being higher in the summer-grazed area than in the ungrazed area. The implications for management are that the more desalinated the area becomes and the higher its clay content, the higher the stocking rate must be to retard the vegetation succession.

Threatened wetlands and ecologically sensitive ecosystems management in Bangladesh

Wetlands constitute a part of human heritage. It has played a significant role in the development of human culture and society. More over it contains very rich components of biodiversity of local, national, and regional significance. They also provide habitat for a variety of resident and migratory waterfowl, a significant number of endangered species, and a large number of commercially important species. Mangrove wetlands are unique environments of floral-faunal assemblages, providing a complex detritus-based food-web for a number of marine and brackish water organisms. Wetlands in Bangladesh have great importance for the country’s economic, industrial, ecological, socioeconomic, and cultural aspects. There are five types of wetlands available in Bangladesh, such as saltwater wetlands, freshwater wetlands, palustrine wetlands, lacustrine wetlands, and manmade wetlands. There are 43 designated wetlands, and some are under threat from indiscriminate utilization, encroachments and reclamation, urbanization and drawbacks from agricultural development, and flood control. Almost 50% of the country’s people are directly dependent on wetlands resources. The vast majority of the poor people in the wetlands areas are dependent on wetlands resources for their nourishment. Wetlands have potential and have been recognized as a driving force for biodiversity conservation and rural socioeconomic improvement. Smart-use of wetlands can solve the ecosystems problems in the floodplain areas. A comprehensive analysis of the various issues leading to wetlands degradation is made in this study. The country needs an adequate interdisciplinary policy and political will to implement it for sustainable management and protection of wetlands and ecologically sensitive ecosystems in Bangladesh. Therefore, a reliable data bank is provided in this study to enhance the conservation measures initiated by the Government.

The Change of Wetland in Hexi Corridor in the Past Thirty Years and a Tentative Discussion on Its Mechanism

In this paper,the wetland in Hexi Corridor was dynamically monitored by remote sensing technology using four different temporal remote sensing data.The results show that the area of the wetland was 14 132.38 km2 in 1973,13 299.44 km2 in 1990,12 519.88 km2 in 2000,and 12 312.38 km2 in 2006.In the past 30 years,the reduced area amounted to 1 820.00 km2,which occupied 12.88% of the total area,with the dynamic degree being-0.39%.Natural wetland has been reduced continuously at an accelerating speed,with swamp reduced most significantly.Meanwhile,the area of man-made wetland has steadily increased,especially in recent years.The number and density of wetland patches have increased,and the fragmentation degree now is higher than that in the past.The diversity index and evenness index have increased continuously,the difference between the proportions of various wetlands have decreased,and the distribution wetlands tends to become uniform.Temperature,precipitation,uplift of the Tibetan plateau and other natural factors seem to be the important causes for wetland change in Hexi Corridor.In addition,human activities have undoubtedly aggravated such a tendency.

Conservation status of Ramsar sites of Nepal Tarai: an overview

Nepal houses only inland freshwater wetlands, ranging from floodplains of snow-melt-fed cold Himalayan rivers, warm rivers originating in the mid hills, high altitudinal glacial lakes to hot springs, ponds, ox-bow lakes, marshes and swamps. These wetlands support several endemic and globally threatened species of flora and fauna. Besides, wetland sites have significant recreational, religio-cultural and spiritual values. There are over 240 wetland sites in Nepal, of which 163 are in the Terai (plain lowland). Wetlands found in Tarai are comparatively more inventoried than the wetlands of mountains and the Himalayan regions of the country. The Terai region (below 300 m) covers about 14% of the country's total area, where half of Nepal's total populations exist. About 11% population of the country is wetland dependent; majority of them are living in the Terai region. The country has nine Ramsar sites, of which, four are in the Tarai region. Among them, two sites (Koshi Tappu wetland, and Beeshazar and associated lakes) lie inside the protected areas and two sites (Ghodaghodi Lake area and Jagadishpur Reservoir) are distributed outside the protected areas. The Koshi Tappu wetland lies along the floodplains of the Sapta Koshi River in the eastern Tarai within the Koshi Tappu Wildlife Reserve. It is the first Ramsar site in Nepal. Beeshazar and associated lakes lies in the buffer zone of the Chitwan National Park along the inner Tarai of Central Nepal. The Ghodaghodi Lake Area (2500 ha) lies in the far western Nepal, and comprises about 14 large and small ox-bow lakes/ponds with associated marshes, swamps, river/streams, springs, seasonal marshy grasslands and human made wetlands, out of them, Ghodaghodi Lake (138 ha) is the largest natural lake in the Nepal's Tarai. The lake system falls between the Bardia National Park and the Suklaphanta Wildlife Reserve of the country and the surrounding forest functions as an important corridor for the movement of wildlife between these as well as the Tarai and the northern Siwalik hills. Similarly, the Jagadishpur Reservoir (225 ha) which lies in Central Nepal's Tarai is the largest man-made wetland in Nepal for irrigation purpose. It is an important site for migratory and resident birds. In this paper we highlight the status, threats, conservation issues and management practices of these Ramsar sites lying in Nepal Tarai. Key-words: Ghodaghodi Lake; Jagdishpur Reservoir; Nepal Tarai; outside protected area; wetlands.DOI: 10.3126/botor.v6i0.2914 Botanica Orientalis - Journal of Plant Science (2009) 6: 76-84

Laboratory and Field Investigations of Pestiferous Chironomidae (Diptera) in Some Man-Made Wetlands in Central Florida, USA

A 1-year larval and adult population survey of pestiferous chironomids was conducted in 4 man-made wetlands in a resort area of central Florida, USA. Benthic samples were randomly collected from each wetland at least once every month. Geocoordinates, water depth, and physical composition of substrates at each larval sample location were noted. Adult midge populations were sampled weekly around the wetlands by employing 10 New Jersey light traps permanently placed in the area. Chironominae and Tanypodinae midges occurred in the larval and adult samples; a few Orthocladiinae were also taken. Among Chironominae, Chironomini (mostly Polypedilum spp., Cryptochironomus spp., Glyptotendipes paripes, and Goeldichironomus carus) and Tanytarsini (mostly Tanytarsus spp.), and some other Chironomidae were recorded. Tanypodinae were quantitatively not important. Monthly mean number of total adults per trap-night ranged from 23 in February to 211 in October. Annual mean larval density and range of total chironomids in the study wetlands amounted to 1,128/m2, range: 0-12,332/m2. The total larvae were most abundant in May. Tanytarsus spp. and Polypedilum spp. were numerically the most predominant spatially as well as temporally. Mean water depth at the sampled locations was 1.83 m (range: <1-8.75 m); 47% of the total collected larvae occurred at <1-m water depth and 53% at >1-m-deep water. Of all sampled locations, substrates such as sand, mixed substrates, and muck were respectively encountered at 656, 371, and 299 locations. The predominance of sand and mixed substrates was conducive to supporting the numerically dominant Tanytarsus spp. and Polypedilum spp. In laboratory bioassays, Tanytarsus spp., Polypedilum spp., Glyptotendipes paripes, and Goeldichironomus carus were highly susceptible to temephos, as well as to s-methoprene. Bacillus thuringiensis serovar. israelensis was most effective against Tanytarsus spp. and least against Goeldichironomus carus.

The Economic Value of Wetland Conservation and Creation: A Meta-Analysis

The rationale for conservation and creation of wetlands stems from the recognition of both their ecological and economic values. This paper examines the welfare impacts of goods and services provided by wetlands. We collected 385 estimates of the economic value of 181 natural and man-made wetlands from 167 studies worldwide. The resulting database is less biased towards North America than previous reviews of the literature. The relative importance of characteristics of the valuation study, of the wetland site, and of the socio-economic and geographical context is estimated by means of a meta-regression analysis of wetland values. Provision of amenities, flood control and storm buffering, and water quality improvement are the most highly valued wetland services. The relevance of the socio-economic and geographical context clearly emerges from the analysis and, in particular, the proximity to other wetland sites is negatively correlated with valuations. An analysis of the effect of environmental stress on wetland value shows that the latter increases with stress from human development activities and uses. In addition to the basic meta-regression model, the influence of authorship effects and of the geographic regions is examined by means of a multi-level approach. A second extended meta-regression model including cross-effects shows that the valuations of specific services vary according to the type of wetland producing them.

Distribution of Adult Odonata Among Localized Wetlands in East-central Mississippi

We measured species richness and composition of adult Odonata and inferred habitat preferences among man-made wetland sites and surrounding tracts of natural bottomland forest. Cumulative species richness and composition were described by proportion coefficients and beta diversity indices. The three man-made sites provided open space resources, and more species were observed in each than in the floodplain forest. Twenty-nine of 42 species documented over a four-month period were observed in only one or two of the four wetlands studied. Large differences in species assemblages between the immediately adjacent ditch and marsh sites were the best evidence for high habitat affinity because distance and structural barriers to movement were absent. Such compositional asymmetry may reflect differential vegetative and reproductive suitability of the habitats. Results suggest that the open-canopy wetlands supported higher diversity of adult Odonata, and that distinct odonate assemblages were found among different habitat types in this flood-plain wetland complex.

BREEDING DUCKS AND THEIR HABITATS IN THE HIGH PLAINS OF TEXAS

Abstract The High Plains of Texas is one of the southernmost nontraditional breeding areas for many duck species in North America. Because of a paucity of information on breeding ducks there, we conducted roadside surveys of breeding ducks and their habitats during May and June from 1988 through 1992. Breeding pairs of 15 species were observed on 6 types of ponds (natural and man-made wetlands containing surface water). Mallard (Anas platyrhynchos) density ranged from 9.1 to 23.1 pairs/100 km2, and density for all species combined ranged from 14.8 to 46.7 pairs/100 km2 (all years and survey periods included). Occupancy rates were highest on playa lakes and impoundments, though all pond types had occupancy rates exceeding 26% (all surveys and years). Duck pairs per occupied pond were highest on playa lakes (>7 and >4 on May and June surveys, respectively), followed by impoundments (>5 and >2) and entrenched draws (>2 and >3). Although the density of breeding pairs in the High Plains of Texas (47 pairs/100 ...

A matter of manure

When you bite into a juicy steak, the last thing you’re probably thinking about is feedlots, and I don’t blame you. But between meals, you might consider one of the most serious ongoing threats to our water supply: “non-point source” (NPS) runoff from farms. Cattle, pigs, and poultry produce about 500 million tons of manure annually in the US – more than three times as much as humans – but the disposal of that waste has gone largely unregulated. According to the EPA’s latest National Water Quality Inventory report, agriculture is the leading contributor to NPS water-quality impairments, accounting for 60% of the river miles and half of the lake acreage affected by pollution in North America. A significant proportion of this comes from places that raise animals, not crops. For those who find it hard to imagine a turkey without stuffing, feedlots are those sprawling, malodorous operations filled with milling cows or chickens. In recent years, “concentrated animal feeding operations” (CAFOs) – housing 300 or more cattle, or 16 500 or more turkeys for at least 45 days – have become the focus of serious environmental concern. Runoff from poorly managed CAFOs can carry pollutants (including sediment, excess nutrients, and pathogens) into surface waters, and ground water can also be contaminated by seepage from animal waste. Airborne emissions are another problem, one that is often obvious when you drive past one. Regulators have long believed that CAFO discharges can be limited by appropriately managing and storing wastewater and runoff. Recently, the EPA proposed a solution to the problem, along the lines of the old adage, “the solution to pollution is dilution”. The final rule, published on February 12, strengthens existing regulatory programs for CAFOs, where more manure is often generated than is reported. Under the new rule, about 15 500 of the largest manure-producing facilities, responsible for 60% of the pollutants, will be required to obtain National Pollutant Discharge Elimin ation System (NPDES) permits. Currently, only about 4500 have permits. The rule also requires Comprehensive Nutrient Management Plans (CNMP) to address nutrients, pathogens, and other pollutants. These can encompass feed management, land management, record keeping, and manure handling, storage, and application. However, the number of CAFOs covered by the final rule is much less than the roughly 39 000 that would have been covered under a rule proposed by the Clinton administration in 2001, which would have included many smaller farms. While the NRDC suits seek to tighten the regulation of CAFOs, the industry lawsuits were filed to attack certain aspects of the new regulatory authority on CAFOs, and to protect the individual industries’ positions. Environmental groups are also concerned about the Bush administration’s decision to drop a provision that would have required companies that produce and sell meat products to obtain NPDES permits. The environmental groups argue that large corporations should be held liable for the waste management practices of the contract farmers who actually raise the animals. Controversy has also arisen, understandably, over allowing farms to write their own permits for spraying diluted manure on fields as fertilizer, without agency oversight or public review. Under the EPA rule, CNMPs and strict rules for annual reporting will be required by 2006 as a way of regulating sprayfields. Once the plans are in place, the feeding operations will be required to submit annual reports to the EPA. EPA officials say they considered a number of alternative technologies for waste treatment and disposal, including manmade wetlands that treat waste, batch reactors, digesters, composters, and covered lagoons, but ultimately deemed those methods to provide less protection against NPS runoff than open lagoons. The American Farm Bureau Federation and other groups originally opposed to the Clinton rule have reacted, with certain reservations, more favorably to the new version than the one announced in 2001. They see the current administration’s version as workable and compatible with the environmental initiatives authorized in the 2002 Farm Bill. According to the EPA, the new rule will cost the industry about $335 million, and will provide between $240 and $335 million in environmental benefits. The agency says it will result in the reduction of 56 million pounds of phosphorus, 110 million pounds of nitrogen, 2.1 million pounds of sediment, and about 911 000 pounds of metals per year. So, although the smell may still seep through our car windows, we could see less feedlot pollution running into our waterways in the near future. And that could make your next chicken dinner even tastier. Douglass Rohrman

A Matter of Manure

When you bite into a juicy steak, the last thing you’re probably thinking about is feedlots, and I don’t blame you. But between meals, you might consider one of the most serious ongoing threats to our water supply: “non-point source” (NPS) runoff from farms. Cattle, pigs, and poultry produce about 500 million tons of manure annually in the US – more than three times as much as humans – but the disposal of that waste has gone largely unregulated. According to the EPA’s latest National Water Quality Inventory report, agriculture is the leading contributor to NPS water-quality impairments, accounting for 60% of the river miles and half of the lake acreage affected by pollution in North America. A significant proportion of this comes from places that raise animals, not crops. For those who find it hard to imagine a turkey without stuffing, feedlots are those sprawling, malodorous operations filled with milling cows or chickens. In recent years, “concentrated animal feeding operations” (CAFOs) – housing 300 or more cattle, or 16 500 or more turkeys for at least 45 days – have become the focus of serious environmental concern. Runoff from poorly managed CAFOs can carry pollutants (including sediment, excess nutrients, and pathogens) into surface waters, and ground water can also be contaminated by seepage from animal waste. Airborne emissions are another problem, one that is often obvious when you drive past one. Regulators have long believed that CAFO discharges can be limited by appropriately managing and storing wastewater and runoff. Recently, the EPA proposed a solution to the problem, along the lines of the old adage, “the solution to pollution is dilution”. The final rule, published on February 12, strengthens existing regulatory programs for CAFOs, where more manure is often generated than is reported. Under the new rule, about 15 500 of the largest manure-producing facilities, responsible for 60% of the pollutants, will be required to obtain National Pollutant Discharge Elimin ation System (NPDES) permits. Currently, only about 4500 have permits. The rule also requires Comprehensive Nutrient Management Plans (CNMP) to address nutrients, pathogens, and other pollutants. These can encompass feed management, land management, record keeping, and manure handling, storage, and application. However, the number of CAFOs covered by the final rule is much less than the roughly 39 000 that would have been covered under a rule proposed by the Clinton administration in 2001, which would have included many smaller farms. While the NRDC suits seek to tighten the regulation of CAFOs, the industry lawsuits were filed to attack certain aspects of the new regulatory authority on CAFOs, and to protect the individual industries’ positions. Environmental groups are also concerned about the Bush administration’s decision to drop a provision that would have required companies that produce and sell meat products to obtain NPDES permits. The environmental groups argue that large corporations should be held liable for the waste management practices of the contract farmers who actually raise the animals. Controversy has also arisen, understandably, over allowing farms to write their own permits for spraying diluted manure on fields as fertilizer, without agency oversight or public review. Under the EPA rule, CNMPs and strict rules for annual reporting will be required by 2006 as a way of regulating sprayfields. Once the plans are in place, the feeding operations will be required to submit annual reports to the EPA. EPA officials say they considered a number of alternative technologies for waste treatment and disposal, including manmade wetlands that treat waste, batch reactors, digesters, composters, and covered lagoons, but ultimately deemed those methods to provide less protection against NPS runoff than open lagoons. The American Farm Bureau Federation and other groups originally opposed to the Clinton rule have reacted, with certain reservations, more favorably to the new version than the one announced in 2001. They see the current administration’s version as workable and compatible with the environmental initiatives authorized in the 2002 Farm Bill. According to the EPA, the new rule will cost the industry about $335 million, and will provide between $240 and $335 million in environmental benefits. The agency says it will result in the reduction of 56 million pounds of phosphorus, 110 million pounds of nitrogen, 2.1 million pounds of sediment, and about 911 000 pounds of metals per year. So, although the smell may still seep through our car windows, we could see less feedlot pollution running into our waterways in the near future. And that could make your next chicken dinner even tastier. Douglass Rohrman

Status of ecological health of wetlands in Punjab, India

To identify important wetlands from ecological, socio-economic, hydro-biological, religious and recreational points of view, a study was undertaken in the state of Punjab with the aim of designing suitable conservation strategies and developing site-specific management plans for their timely implementation. The survey shows that in Punjab, all the natural and man-made wetlands cover an area of about 23000 ha. While most of the natural wetlands are under severe stress from reclamation for agriculture, the man-made wetlands which are primarily being maintained for the purpose of meeting water requirements of Punjab and other adjoining states are under threat of general ecological degradation. Though conservation and protection of wetlands in the state have attracted the attention of the government, the general attitude of the public towards these ecosystems is negative with efforts directed toward making alternate uses of the wetlands in the short-term. As a consequence, a large number of natural wetlands have vanished and the trend is continuing. Some of the very prominent wetlands that have totally lost their ecological character due to reclamation include Bhupinder Sagar, Chhangali Chhamb, and Rahon de Chhamb. Major reasons for their loss include drainage of low lands, reduced flow of water into natural wetlands, siltation and encroachments. Due to the continuous loss of natural wetlands in the state not only the local hydrological regime is changing rapidly but also the biological diversity has come under threatening pressure. This study has found that immediate conservation measures have to be implemented in some important wetlands in the state. The Punjab State Council for Science and Technology has identified five wetlands, Keshopur-Miani Jheel, Chhawarian Bhangar Chhamb, Jastarwal Jheel, Mand Bharthala and Dholbaha Reservoir, to be designated as wetlands of state significance. These are in addition to Harike, Kanjli and Ropar wetlands that have been included in the list of wetlands of national importance.

Natural and Constructed Wetlands in Canada: An Overview

Abstract A review of freshwater wetland research in Canada was conducted to highlight the importance of these ecosystems and to identify wetland research needs. Both natural and constructed wetland systems are discussed. Natural wetlands are an important part of the Canadian landscape. They provide the habitat for a broad variety of flora and fauna and contribute significantly to the Canadian economy. It is estimated that the total value derived from consumptive and non-consumptive activities exceeds $10 billion annually. The past decades have witnessed the continued loss and degradation of wetlands in Canada. In spite of recent protection, Canadian wetlands remain threatened by anthropogenic activities. This review shows that more research on fate and transport of pollutants from urban and agricultural sources in wetland systems is needed to better protect the health and to assure the sustainability of wetlands in Canada. Furthermore, improved knowledge of hydrology and hydrogeochemistry of wetlands will assure more effective management of these ecosystems. Lastly, better understanding of the effect of climate change on wetlands will result in better protection of these important ecosystems. Constructed wetlands are man-made wetlands used to treat non-point source pollution. The wetland treatment technology capitalizes on the intrinsic water quality amelioration function of wetlands and is emerging as a cost-effective, environmentally friendly method of treating a variety of wastewaters. The use of wetland technology in Canada is, however, less common than in the U.S.A. A number of research needs has to be addressed before the wetland treatment technology can gain widespread acceptance in Canada. This includes research pertaining to cold weather performance, including more monitoring, research on design adaptation and investigation of the effects of constructed wetlands on wildlife.