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Journal articles on the topic 'Urban wetlands'
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1
Hutto, David, and Kyle Barrett. "Do urban open spaces provide refugia for frogs in urban environments?" PLOS ONE 16, no. 1 (January 22, 2021): e0244932. http://dx.doi.org/10.1371/journal.pone.0244932.
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Urbanization is among the largest threats to wildlife populations through factors such as fragmentation, isolation, and habitat destruction. Urban open spaces, such as parks and golf courses, have the potential to provide wildlife with suitable habitat within an urbanized matrix. These refugia may be particularly important for amphibians, which represent one of the most endangered and least vagile vertebrate groups on earth. During the spring and summer of 2018, we conducted surveys to determine the presence of anurans at 51 wetland sites within the Piedmont ecoregion of South Carolina. Nearly one-third of these wetlands were located within urban open spaces, one-third in low development areas, and one-third in highly developed areas. Impervious surface and total road length surrounding the wetlands were measured at two scales, a core habitat scale (300 m) and average maximum migration scale (750 m), and we measured several within-wetland habitat variables. Urban Open Space wetlands had levels of surrounding impervious surface similar to High Urbanization wetlands at the larger scale and were intermediate between Low and High Urbanization wetlands at the smaller scale. The total length of road segments occurring within buffers (at both scales) surrounding our study wetlands was higher for Urban Open Space compared to Low and High Urbanization sites. Among the within-wetland variables measured, Low Urbanization sites had higher canopy cover and were more likely to have a terrestrial buffer zone relative to the other categories. Species richness decreased significantly as total road length increased among all wetlands. Wetland category was not a significant driver explaining species richness, but β-diversity was more variable among Urban Open Space wetlands than either Low or High Urbanization wetlands. Urban Open Space wetlands did not appear to increase suitability for anurans relative to High Urbanization wetlands. Urban Open Space wetlands had higher variability in species composition, which was perhaps attributable to the diversity among sites represented in the Urban Open Space category.
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Kai Xu, Chunfang Kong, Gang Liu, Chonglong Wu, Hongbin Deng, Yi Zhang, and Qianlai Zhuang. "Changes of urban wetlands in Wuhan, China, from 1987 to 2005." Progress in Physical Geography: Earth and Environment 34, no. 2 (March 30, 2010): 207–20. http://dx.doi.org/10.1177/0309133309360626.
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Urban wetlands play a significant role in the sustainable development of the urban eco-environment. However, accelerated urbanization has caused rapid changes in urban wetland landscape patterns, which may seriously affect their functions. Based on land-use maps, TM images, and field data from the Wuhan wetlands, the spatiotemporal evolution and wetland landscape pattern were quantitatively analyzed, with reference to landscape ecology indices of diversity, fragmentation, dominance, shape, and dimension. The results showed that: (1) the natural wetland area decreased: lake wetlands and marsh wetlands decreased by 18.71% and 50.3% from 1987 to 2005, respectively; (2) artificial wetland area increased by 47.75% in Wuhan over the same period; (3) the lake wetland area of Wuhan declined due to the conversion of large lakes to smaller ones; (4) the value of the diversity index (H), evenness index (E), and fragmentation index (F) decreased, while the value of the dominance index (D) increased from 1987 to 2005; (5) the landscape shape index (LSI) and fractal dimension (FD) of the river wetlands, lake wetlands, bottomland wetlands, and marsh wetlands decreased, while the LSI and FD of the reservoir and pond wetlands increased from 1987 to 2005; and (6) natural, societal, and economic, as well as human, activities are major factors for the structural changes in the Wuhan wetland landscape, as revealed by canonical correlation analysis. Results suggest that the ecological environment of urban wetlands should be protected to maximize the services of urban wetland ecosystems in Wuhan, China.
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Gilbert, Nicolas, Roberta Fulthorpe, and Andrea E. Kirkwood. "Microbial diversity, tolerance, and biodegradation potential of urban wetlands with different input regimes." Canadian Journal of Microbiology 58, no. 7 (July 2012): 887–97. http://dx.doi.org/10.1139/w2012-066.
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Though microbial transformations are the primary mechanism of contaminant attenuation in wetlands, much remains to be known about microbial communities in urban wetlands. In this study, the microbial communities from urban wetlands with different runoff regimes (i.e., a contaminated remnant wetland, a constructed wetland, and a remnant wetland) were assessed for their capacity to attenuate and tolerate typical urban runoff pollutants. Results from denaturing gradient gel electrophoresis of 16S rRNA genes showed relatively high similarity in community composition among the wetlands. Community-level physiological profiles had similar results but exhibited within-site variation in both the contaminated remnant and remnant wetlands. All wetland communities were less tolerant to copper than 2,4-dichlorophenoxyacetic acid; however, the contaminated remnant wetland had the highest tolerance. All study wetlands had a limited capacity to biodegrade model chlorinated aromatic compounds (e.g., 2,4-dichlorophenoxyacetic acid and 3-chlorobenzoate). Though having different input regimes and contaminant exposure histories, the study wetlands were generally similar with respect to microbial community diversity and function. Additionally, the generally low capacity for these wetlands to biodegrade mobile chlorinated organic contaminants offers preliminary insight into the limited ecosystem services these wetlands may provide in urban environments.
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Husband, Danielle M., and Nancy E. McIntyre. "Urban Areas Create Refugia for Odonates in a Semi-Arid Region." Insects 12, no. 5 (May 11, 2021): 431. http://dx.doi.org/10.3390/insects12050431.
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In western Texas, most wetlands are fed from precipitation runoff, making them sensitive to drought regimes, anthropogenic land-use activities in their surrounding watersheds, and the interactive effect between these two factors. We surveyed adult odonates in 133 wetlands (49 in grassland settings, 56 in cropland, and 28 in urban areas) in western Texas from 2003–2020; 33 species were recorded. Most species were widespread generalists, but urban wetlands had the highest species richness, as well as the most unique species of any of the three wetland types. Non-metric, multidimensional scaling ordination revealed that the odonate community in urban wetlands was distinctly different in composition than the odonates in non-urban wetlands. Urban wetlands were smaller in surface area than the other wetland types, but because they were fed from more consistently available urban runoff rather than seasonal precipitation, they had longer hydroperiods, particularly during a multi-year drought when wetlands in other land-cover contexts were dry. This anthropogenically enhanced water supply was associated with higher odonate richness despite presumably impaired water quality, indicating that consistent and prolonged presence of water in this semi-arid region was more important than the presence of native land cover within which the wetland existed. Compared to wetlands in the regional grassland landscape matrix, wetlands in agricultural and urban areas differed in hydroperiod, and presumably also in water quality; these effects translated to differences in the regional odonate assemblage by surrounding land-use type, with the highest richness at urban playas. Odonates in human environments may thus benefit through the creation of a more reliably available wetland habitat in an otherwise dry region.
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Li, Tianjie, Yang Jin, and Yan Huang. "Water quality improvement performance of two urban constructed water quality treatment wetland engineering landscaping in Hangzhou, China." Water Science and Technology 85, no. 5 (February 21, 2022): 1454–69. http://dx.doi.org/10.2166/wst.2022.063.
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Abstract For typical wastewater treatment processes of urban sewage, plants are often noneffective to improve water qualities of lightly polluted domestic sewage, and urban constructed water quality treatment (WQT) wetlands designed with engineering landscape methods are utilized to optimize both water qualities and landscape values in recent years. The research determines the effects of two typical ecological engineering landscaping projects of urban constructed WQT wetlands by analysing their effects of wastewater quality improvements. Differences of water quality indicators (WQI) respectively among different treatment stages of wetlands includes surface flow wetland, vertical flow wetland, floating wetland islands etc., which have been measured and compared. Evaluation of urban constructed WQT wetlands engineering landscaping has been concluded based on comparisons among hydrological indicators and water quality indicators, i.e. pH, DO, NH3-N, CODCr, TP. Removal effects of individual indicators, includes NH3-N, CODCr and TP during different treatment stages have been quantitatively analysed. In accordance with quantitative analysis, benefits and deficiencies of practical landscape design of urban constructed WQT wetlands are concluded. By adapting proper principles in engineering landscaping, environmental and economic benefits can be achieved to create sustainable landscapes of urban constructed WQT wetlands.
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Kabiri, Stella, Molly Allen, Juduth Toma Okuonzia, Beatrice Akello, Rebecca Ssabaganzi, and Drake Mubiru. "Detecting wetland encroachment and urban agriculture land classification in Uganda using hyper-temporal remote sensing." AAS Open Research 3 (February 16, 2022): 18. http://dx.doi.org/10.12688/aasopenres.13040.2.
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Background: Urbanization is an important indicator of economic growth and social change but is associated with environmental degradation, which threatens the sustainable growth of African cities. One of the most vulnerable ecosystems in urban areas are wetlands. In Uganda, wetlands cover an area of 11% of the country’s land area. Half of the wetland areas in Ugandan cities have been converted to industrial and residential areas, and urban agriculture. There is limited information on the extent of wetland conversion or utilization for urban agriculture. The objective of this study was to investigate the extent of wetlands lost in two Ugandan cities, Wakiso and Kampala, in the last 30 years. Secondly, we extracted crop agriculture in the wetlands of Kampala and Wakiso from hyper-temporal satellite image analysis in an attempt to produce a spatial detail of wetland encroachment maps of urban agriculture using a reproducible mapmaking method. Methods: Using a field survey and free remote sensing data from Landsat TM 1986 and Landsat ETM 2016 we classified the rate of wetland loss and encroachment between the years 1986 and 2016. We used MODIS NDVI 16-day composites at a 500-meter spatial resolution to broaden the analysis to distinguish distinctive crops and crop mixtures in the encroached wetlands for urban agriculture using the ISODATA clustering algorithm. Results: Over 30 years, 72,828 ha (73%) of the Wakiso-Kampala wetlands have been lost meanwhile agriculture areas have doubled. Of this 16,488 ha (23%) were converted from wetlands. All cultivated agriculture in Kampala was in the wetlands while in Wakiso, 73% of crop agriculture was in the wetlands. The major crops grown in these urban wetlands were banana (20%), sugarcane (22%), maize (17%), Eucalyptus trees (12%), sweet potatoes (10%), while ornamental nurseries, pine trees, vegetables, and passion fruits were each at 5%.
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Wang, Ming, Dehua Mao, Yeqiao Wang, Kaishan Song, Hengqi Yan, Mingming Jia, and Zongming Wang. "Annual Wetland Mapping in Metropolis by Temporal Sample Migration and Random Forest Classification with Time Series Landsat Data and Google Earth Engine." Remote Sensing 14, no. 13 (July 2, 2022): 3191. http://dx.doi.org/10.3390/rs14133191.
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Wetlands provide various ecosystem services to urban areas, which are crucial for sustainable urban management. With intensified urbanization, there has been marked loss of urban natural wetland, degradation, and related urban disasters in the past several decades. Rapid and accurate mapping of urban wetland extent and change is thus critical for improving urban planning toward sustainability. Here, we have developed a rapid method for continuous mapping of urban wetlands (MUW) by combining automatic sample migration and the random forest algorithm (SM&RF), the so-called MUW_SM&RF. Using time series Landsat images, annual training samples were generated through spectral angular distance (SAD) and time series analysis. Combined with the RF algorithm, annual wetland maps in urban areas were derived. Employing the Google Earth Engine platform (GEE), the MUW_SM&RF was evaluated in four metropolitan areas in different geographical and climatic regions of China from 1990 to 2020, including Tianjin, Hangzhou, Guangzhou, and Wuhan. In all four study areas, the generated annual wetland maps had an overall accuracy of over 87% and a Kappa coefficient above 0.815. Compared with previously published datasets, the urban wetland areas derived using the MUW_SM&RF approach achieved improved accuracy and thus demonstrated its robustness for rapid mapping of urban wetlands. Urban wetlands in all four cities had variable distribution patterns and showed significantly decreased trends in the past three decades. The annual urban wetland data product generated by the MUW_SM&RF can provide invaluable information for sustainable urban planning and management, so as for assessment related to the United Nation’s sustainable development goals.
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Li, Han, Radmila Petric, Zinah Alazzawi, Jake Kauzlarich, Rania H. Mahmoud, Rasheed McFadden, Niklas Perslow, et al. "Four Years Continuous Monitoring Reveals Different Effects of Urban Constructed Wetlands on Bats." Land 10, no. 10 (October 14, 2021): 1087. http://dx.doi.org/10.3390/land10101087.
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Proactive artificial wetland constructions have been implemented to mitigate the loss of wetlands and their ecosystem services. As wetlands are habitats for bats, short-term (one or two years) studies find that constructed wetlands can immediately increase local bat activity and diversity. However, it is not clear how constructed wetlands affect bats through time while the wetlands are aging. We collected four years of continuous bat acoustic monitoring data at two constructed wetlands in an urban park in Greensboro, NC, USA. We examined bat activity and community composition patterns at these wetlands and compared them with reference sites in the city. With four years of data, we found that the effects of constructed wetlands were both habitat- and species-specific. The wetland in forests significantly increased bat activity, while the wetland in the open grass altered bat community composition. Specifically, in terms of species, we found that over time, constructed wetlands no longer attracted more big brown, silver-haired, or evening bats than control sites while the wetlands aged, highlighting the need to study broadly how each bat species uses natural and artificial wetlands. We emphasize the importance of long-term monitoring and the periodical evaluation of wildlife conservation actions.
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Toroitich, Caleb, Mugwima Njuguna, and Dennis Karanja. "Effects of urban wetland patch pattern on the biodiversity of aquatic birds in Nairobi, Kenya." Journal of Agriculture, Science and Technology 21, no. 1 (April 26, 2022): 83–109. http://dx.doi.org/10.4314/jagst.v21i1.8.
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Urban wetlands are ubiquitous landscape elements that affect the spatial pattern and functions of cities. Despite being rich and important habitats for a variety of birds, they are continually being isolated or lost. Isolation and loss negatively impact on the integrity of the urban landscape pattern and compromises on biophilic planning and development. Since urbanization is a continuous cultural process, it is important to investigate how its impacts, which are invariably in conflict with nature, would portend for aquatic bird communities in urban areas. This study sought to determine the variability and relationship between the structural patch pattern of palustrine wetlands in Nairobi and the species richness and abundance of aquatic birds in these wetlands. From a population of 300 wetlands, this study used heterogeneous sampling to identify and investigate 31 palustrine wetlands spread across the city of Nairobi. For each of these wetlands, a variety of landscape metrics were calculated and the species diversity of aquatic birds was quantified. Multiple regression analysis was performed in IBM SPSS Statistics 21 to determine the relationships between wetland patch pattern and wetland biodiversity. The study found that patch pattern significantly affects aquatic bird biodiversity, R² = .516, F (7, 23) = 3.498, p < .05. It was also found that the characteristics of the wetland neighbourhood significantly affected aquatic bird biodiversity, R² = .301, F (3, 27) = 3.867, p < .05. This study highlights the need to mainstream, plan, and design for the conservation and monitoring of spatial patterns and biodiversity of palustrine wetlands in urban landscapes. In doing so, biophilic cities are created, bio-systemic urban infrastructure is generated, human wellbeing is enhanced, and urban wetland ecosystem services are valued.
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HETTIARACHCHI, MISSAKA, CLIVE McALPINE, and T. H. MORRISON. "Governing the urban wetlands: a multiple case-study of policy, institutions and reference points." Environmental Conservation 41, no. 3 (November 28, 2013): 276–89. http://dx.doi.org/10.1017/s0376892913000519.
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SUMMARYWorldwide, coastal and floodplain wetlands are rapidly urbanizing, making them highly vulnerable to biodiversity loss, biological invasion and climate change. Yet urban wetlands management is an understudied area of global environmental research. Different policy approaches and institutional arrangements in place for urban wetlands governance have to be studied comparatively to obtain a better understanding of the current issues. This paper investigates four urban wetland policy regimes and the application of ecological reference points across four countries. The regimes are discussed within the context of global policy trends, urbanization patterns and environmental change. The analysis illustrates that the four cases deviate substantially in certain characteristics and converge in others. Global trends such as environmental treaties and restructuring of city spaces are common policy drivers for all cases. Conversely, the localized specific problems have yielded specialized policy responses in each case. Declaration of fixed biological reference points for wetlands were not used at any stage of the policy development process. However, the wetland managers formally or informally set up ecosystem-services oriented benchmarks for urban wetland management. Globally-applicable normative policy directives or universal ecological reference points seem bound to fail in urban wetlands governance. However, in designing effective urban wetland policy and institutions at the regional scale, both context-specific and generalized lessons from empirical policy evaluation of multiple case studies need to be jointly considered. Based on the characteristics of the policy regimes analysed in this study, a hypothetical framework for urban wetland policy evaluation is proposed; this has yet to be validated by empirical application to actual cases.
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Kometa, Sunday Shende, Jude Ndzifon Kimengsi, and Dereck M. Petiangma. "Urban Development and its Implications on Wetland Ecosystem Services in Ndop, Cameroon." Environmental Management and Sustainable Development 7, no. 1 (November 13, 2017): 21. http://dx.doi.org/10.5296/emsd.v7i1.12141.
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Wetlands provide a diversity of ecosystem services (provisioning, regulatory, supporting and cultural services) which are essential for the human society. This is particularly necessary in cases where large urban agglomerations exist. These services are increasingly coming under pressure as a result of rapid and uncontrolled urban development which remains phenomenal in the developing world. Cameroon can boast of a number of wetland environments particularly, the Waza Logone flood plain, the wetlands of the Bakassi Peninsula, Lake Barombi Mbo and the Ndop Plains. The wetland ecosystems of the Ndop Plains have increasingly come under pressure as a result of urban development which is mirrored in population growth, housing and other infrastructural developments. While significant research works have been undertaken on aspects related to wetlands, agriculture and climate variability in the Ndop plains, there is insufficiency scientific information on the implications of urban development on wetland ecosystem services. Using questionnaire (where we systematically sample 140 households) and Landsat images which were complemented by field observations, relevant data were generated. With the aid of SPSS (version 21), the correlation between wetland ecosystem services and urban development at 0.05 level of significance was analysed. Our results reveal a significant negative relationship (r = -0.551 and -0.682) between urban development and the state of wetlands and their ecosystem services. This was further buttressed by geospatial data which revealed that the Ndop urban space increased from 3.7km2 in 1999 to 11.7km2 in 2017. In this regard, we suggest that the coordination of the urban development process through land use planning and zoning is imperative in the face of unabated urban development. We equally suggest the need to implement wetland management policies in line with the Ramsar convention’s paradigm on the “wise use” of wetlands.
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Kabiri, Stella, Molly Allen, Juduth Toma Okuonzia, Beatrice Akello, Rebecca Ssabaganzi, and Drake Mubiru. "Detecting level of wetland encroachment for urban agriculture in Uganda using hyper-temporal remote sensing." AAS Open Research 3 (May 12, 2020): 18. http://dx.doi.org/10.12688/aasopenres.13040.1.
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Background: Urbanization is an important indicator of economic growth and social change but is associated with environmental degradation. In Uganda, wetlands cover an area of 11% of the country’s land area, of which half have been converted to industry and residential areas, and urban agriculture. Here, we investigate the extent of wetlands lost in two Ugandan cities, Wakiso and Kampala, in a period of 30 years. Secondly, we demonstrate a simple methodology to monitor agriculture on encroached wetlands. Methods: Using a field survey and free remote sensing data from Landsat TM 1986 and Landsat ETM 2016 we classified the rate of wetland loss and encroachment from 1986 to 2016. Using MODIS NDVI 16-day composites at 500-meter spatial resolution, we generated distinctive crops and crop mixtures in the encroached wetlands for urban agriculture using the ISODATA clustering algorithm. Results: Over 30 years, 72,828 ha (73%) of the Wakiso-Kampala wetlands have been lost. Agriculture areas have doubled, of which 16,488 ha (23%) were reclaimed from wetlands. All cultivated agriculture in Kampala was in the wetlands while in Wakiso, 73% of crop agriculture was in the wetlands. Major crops grown in these urban wetlands were banana (20%), sugarcane (22%), maize (17%), Eucalyptus trees (12%), sweet potatoes (10%). Conclusions: The Kampala-Wakiso wetlands have been disappearing at a rate of 2500 ha annually for the last 30 years. At this rate, there will be no wetlands left by 2029. Policy recommendations should promote wetland reclamation programs so as to restore and reconstruct lost and fragmented wetlands; should mandate food security and poverty eradication to convene with ministries regulating wetlands to merge conflicting policies; and should develop polices that are inclusive of challenges faced by the urban poor while at the same time minimize the pressures on urban environments.
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O. Festus, Olusola, Wei Ji, and Opeyemi Zubair. "Characterizing the Landscape Structure of Urban Wetlands Using Terrain and Landscape Indices." Land 9, no. 1 (January 19, 2020): 29. http://dx.doi.org/10.3390/land9010029.
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Several studies have shown human impacts on urban wetlands. These impacts are mostly studied at broad scales, which may generalize and aggregate important information needed for landscape quantification or terrain analysis. This situation can weakly or inappropriately address the structure of wetland landscapes, thus affecting the assessment of the quantities and qualities of terrestrial wetland habitats. To address these issues for urban wetland dynamics, this study proposes the use of landscape and terrain indices to characterize the landscape structure of urban wetlands at a fine scale in order to assess its usefulness in contributing to wildlife sustainability. To achieve this goal, secondary terrain attribute data are integrated with an object-based satellite image classification at the wetland and watershed level. The result reveals a general swell in wetland coverage at the watershed level. Further analysis shows the size and shape complexities, and edge irregularities are increased significantly at the patch level but slightly at the watershed level. Terrain analysis further reveals a potential increase in wetness and decrease in stream power vulnerability for most of the major wetlands under study. These results suggest that terrain and landscape indices are effective in characterizing the structure of urban wetlands that supports socio-ecological sustainability.
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YUSUPH, MOHAMED, and P. K. T. MUNISHI. "The potential contribution of peri-urban wetlands to livelihood of local communities in Shinyanga Municipality, Tanzania." Bonorowo Wetlands 8, no. 2 (December 1, 2018): 75–83. http://dx.doi.org/10.13057/bonorowo/w080204.
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Yusuph M, Munishi PKT. 2018. The potential contribution of peri-urban wetlands to the livelihood of local communities in Shinyanga Municipality, Tanzania. Bonorowo Wetlands 2: 75-83. The study took place in Shinyanga Municipality, Tanzania to assess the potential contribution of peri-urban wetlands to the livelihood of nearby communities. The specific objectives were to examine the participation of the suburban wetland ecosystems to natural capital-(food production/food security), evaluate the involvement of periurban wetlands ecosystem to financial capital-(household income) and assess the advantages received by farmer groups/associations formed around the utilization of wetlands (social capital). Information was acquired through households and farmer's group/associations questionnaires, focus group discussion as well as field observations. Data were analyzed by employing descriptive and inferential statistics by applying correlation and t-test. As many as 79.2% of the wetland nearby communities rely on the wetlands for food. The major food crops were paddy, fruits, vegetables, and sweet potatoes. The average production levels of cereals, vegetables and fruits were prominently higher in wetlands compared to uplands. In the case of household income wetland cultivation (paddy, vegetables, maize, and fruits) brought about statistically higher household annual mean income of Tshs 2,335,852/year (US$ 1,168) compared to Tshs 197,475/year (US$ 99) produced by upland cultivation. The results further suggested that 70% of the farmer groups/associations established around wetland utilization accessed loans/credit to support agricultural production as an advantage from being members. Sustainable use of peri-urban wetlands in Shinyanga Municipality produces substantial livelihoods to adjacent communities. Conservation of such wetland ecosystems is indispensable for continued contribution to livelihoods while ensuring environmental protection. Further studies are necessary to unravel the nature of social capital associated with utilization of wetland ecosystems.
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Maas, Carly M., William P. Anderson, and Kristan Cockerill. "Managing Stormwater by Accident: A Conceptual Study." Water 13, no. 11 (May 26, 2021): 1492. http://dx.doi.org/10.3390/w13111492.
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Stormwater-driven road salt is a chronic and acute issue for streams in cold, urban environments. One promising approach for reducing the impact of road salt contamination in streams and adjacent aquifers is to allow “accidental wetlands” to flourish in urban areas. These wetlands form naturally as a byproduct of human activities. In this study, we quantified the ability of an accidental wetland in northwestern North Carolina, USA, to reduce the timing and peak concentration of road salt in a stream. Monitoring suggests that flow and transport processes through the wetland reduce peak concentrations and delay their arrival at the adjacent stream. We expand these findings with numerical simulations that model multiple meltwater and summer storm event scenarios. The model output demonstrates that small accidental wetland systems can reduce peak salinities by 94% and delay the arrival of saltwater pulses by 45 days. Our findings indicate that accidental wetlands improve stream water quality and they may also reduce peak temperatures during temperature surges in urban streams. Furthermore, because they find their own niche, accidental wetlands may be more effective than some intentionally constructed wetlands, and provide opportunities to explore managing stormwater by letting nature take its course.
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Hanford, Jayne K., Dieter F. Hochuli, and Cameron E. Webb. "Oviposition Behavior of Culex annulirostris (Diptera: Culicidae) Is Affected by the Recent Presence of Invasive Gambusia holbrooki (Cyprinodontiformes: Poeciliidae)." Journal of Medical Entomology 56, no. 4 (March 24, 2019): 1165–69. http://dx.doi.org/10.1093/jme/tjz027.
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Abstract Constructed wetlands are popular tools for managing threatened flora and fauna in urban settings, but there are concerns that these habitats may increase mosquito populations and mosquito-related public health risks. Understanding the interactions occurring between mosquitoes of public health concern and co-occurring organisms is critical to informing management of these habitats to mitigate potential health risks and balance the multiple values of urban wetlands. This study examined how oviposition behavior of Culex annulirostris Skuse, the most important pest mosquito species associated with freshwater wetland habitats in Australia, is influenced by the presence of Gambusia holbrooki Girard, a widespread invasive fish. Water was collected from urban wetlands that are intensively managed to reduce G. holbrooki populations to assist conservation of locally threatened frogs, and adjacent unmanaged wetlands where G. holbrooki was abundant. Laboratory experiments were conducted to examine the oviposition response by Cx. annulirostris to water samples from these two habitats. Experiments were conducted on two occasions, once in February following draining and refilling of the urban wetlands, and repeated following a substantial rainfall event in March. The results clearly demonstrate that ovipositing mosquitoes were able to detect and avoid water derived from habitats containing fish, even in the absence of the fish themselves. Understanding how invasive species affect the behavior and spatial distribution of pest species such as Cx. annulirostris will enable future wetland design and management to maximize benefits of urban wetlands and minimize potential public health risks.
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Pankratz, S., T. Young, H. Cuevas-Arellano, R. Kumar, R. F. Ambrose, and I. H. Suffet. "The ecological value of constructed wetlands for treating urban runoff." Water Science and Technology 55, no. 3 (February 1, 2007): 63–69. http://dx.doi.org/10.2166/wst.2007.073.
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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.
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Persson, J., N. L. G. Somes, and T. H. F. Wong. "Hydraulics Efficiency of Constructed Wetlands and Ponds." Water Science and Technology 40, no. 3 (August 1, 1999): 291–300. http://dx.doi.org/10.2166/wst.1999.0174.
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Constructed ponds and wetlands are widely used in urban design to serve a number of functions including stormwater management. The design of constructed wetlands for stormwater management involves a number of multi-disciplinary inputs. Fundamental to their sustainable operation are the proper control of the hydrologic regime of the wetland and optimal flow hydrodynamics within the wetland. Many ofthe problems encountered in constructed wetlands can be minimised or avoided by good engineering design principles. Poor wetland hydrodynamics are often identified as a major contributor to wetland management problems. Ponds and wetlands with a high hydraulic efficiency are expected to promote full utilisation ofthe available detention storage and near plug flow conditions. The shape and layout of urban ponds and wetlands are often varied to suit the landscape and to satisfy aesthetic requirements as an urban water feature. These can be achieved while maintaining an effective stormwater treatment outcome if steps are taken to ensure that the hydrodynamic behaviour of the system is not severely compromised. A consistent measure is required to allow the effects of design features to be evaluated against this criterion. This paper introduces a new measure for hydraulic efficiency that combines existing measures of flow uniformity and effective volume. Case studies are presented on the use of this measure to assess the effects of different pond and wetland shapes, locations of inlet and outlet, botanical layouts and basin morphology on the flow hydrodynamics.
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Bu, Lin. "Planning and Design for Constructed Wetlands Based on the Ecological Landscape." Applied Mechanics and Materials 584-586 (July 2014): 662–67. http://dx.doi.org/10.4028/www.scientific.net/amm.584-586.662.
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Urban constructed wetland, effectively used in sewage disposal and ecological restoration, has unique advantages in urban ecological construction. With the development of the ecological landscape concept, constructed wetland gradually has become an important urban ecological landscape. Based on ecological concepts, ecological principle, technical principle and aesthetic principle of planning and the layout, process, landscape, plants and other key issues of design were discussed for the constructed wetland. In this paper, taking Zhongxiang City, Jingmen, Hubei Province as an example, the treatment technology, functional layout and ecological landscape of constructed wetlands were designed based on the analysis of location and site. Through the planning and construction of constructed wetlands, the quality of urban water environment would be improved and the urban water environment with the characteristics of Zhongxiang would be formed, promoting the urban construction to be more green, ecological and livable.
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Díaz-Pinzón, Lida, Lya Sierra, and Francesc Trillas. "The Economic Value of Wetlands in Urban Areas: The Benefits in a Developing Country." Sustainability 14, no. 14 (July 7, 2022): 8302. http://dx.doi.org/10.3390/su14148302.
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Urban growth has impacted natural ecosystems such as wetlands. This situation destabilizes the beneficial contributions of nature, generating a socioeconomic effect. There is a need to quantify the benefits of wetlands in developing countries and urban areas, where the growth of cities is fastest. This is the first valuation study of urban and peri-urban wetlands in Colombia. The methodology includes a benefit transfer (BT) method with a geographical information system (GIS) and an exploratory governance analysis. Because there are few studies on the economic valuation of urban wetlands in Latin America, we present a methodology of interest, which can be easily replicated in other cities of this subcontinent. Based on an economic approach, our results find that 76% of the total value of wetlands is provided by ecosystem services (ES) of existence and legacy value, followed by maintenance of the life cycle of migratory species and water supply. Urban areas are identified where users benefit more than areas where the population exerts greater pressure on wetlands. Weak governance is due to the disarticulation between regulation, land-use planning, and the social-ecological system. This research contributes to urban wetland management policies, as well as to sustainable solutions in cities.
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Rojas-Quezada, Carolina, Felipe Jorquera-Guajardo, and Stefan Steiniger. "Acceder caminando a los humedales urbanos: una oportunidad de recreación y bienestar." Revista Urbano 25, no. 46 (November 30, 2022): 56–67. http://dx.doi.org/10.22320/07183607.2022.25.46.05.
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Urban wetlands in Chilean cities are one of the urban ecosystems most affected by real estate developments. Despite their importance for recreation and biodiversity, they are constantly shrinking due to deficient urban planning processes. However, with the recent boom of green and sustainable cities, wetlands are being revalued through restoration projects and open urban parks, with natural value for the well-being of habitats and the urban population. In this sense, promoting accessibility through suitable infrastructure will contribute to improving the quality of life of inhabitants and the urban environment, specifically through the integration of blue-green infrastructure. Walkable access to a network of wetlands called "La Ruta del Agua" (“the water trail”) has been analyzed here, through a perception-based survey, looking to improve access to nature in cities. The urban wetlands assessed comprise five ecosystems located in different types of neighborhoods in the metropolitan area of Concepción, Chile. Although this is a local case study, it is relevant from a methodological perspective, given the existence of a large number of degraded urban wetlands in Latin America that are in danger of disappearing. The results show that wetlands are accessible by walking, but the fact that they are rarely visited, despite being close to residential areas, reveals a lack of integration as open green spaces, rich in biodiversity, and as places of recreation in the city of Concepción. The results of this study are valuable for the design of future “wetland parks”, one which must consider the ecosystem values, biodiversity, and recreation for people’s well-being.
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Quek, B. S., Q. H. He, and C. H. Sim. "Performance of a pilot showcase of different wetland systems in an urban setting in Singapore." Water Science and Technology 71, no. 8 (February 21, 2015): 1158–64. http://dx.doi.org/10.2166/wst.2015.085.
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The Alexandra Wetlands, part of PUB's Active, Beautiful, Clean Waters (ABC Waters) Programme, showcase a surface flow wetland, an aquatic pond and a sub-surface flow wetland on a 200 m deck built over an urban drainage canal. Water from the canal is pumped to a sedimentation basin, before flowing in parallel to the three wetlands. Water quality monitoring was carried out monthly from April 2011 to December 2012. The order of removal efficiency is sub-surface flow (81.3%) >aquatic pond (58.5%) >surface flow (50.7%) for total suspended solids (TSS); sub-surface (44.9%) >surface flow (31.9%) >aquatic pond (22.0%) for total nitrogen (TN); and surface flow (56.7%) >aquatic pond (39.8%) >sub-surface flow (5.4%) for total phosphorus (TP). All three wetlands achieved the Singapore stormwater treatment objectives (STO) for TP removal, but only the sub-surface flow wetland met the STO for TSS, and none met the STO for TN. Challenges in achieving satisfactory performance include inconsistent feed water quality, undesirable behaviour such as fishing, release of pets and feeding of animals in the wetlands, and canal dredging during part of the monitoring period. As a pilot showcase, the Alexandra Wetlands provide useful lessons for implementing multi-objective wetlands in an urban setting.
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Hassan, Suziana, Søren Bøye Olsen, Syamsul Herman Mohammad Afandi, and Bo Jellesmark Thorsen. "Measuring the Rural and Urban Attitudes towards Wetlands Using the New Ecological Paradigm: Setiu Wetlands, Malaysia." Environment-Behaviour Proceedings Journal 1, no. 2 (June 30, 2016): 132. http://dx.doi.org/10.21834/e-bpj.v1i2.278.
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This study addresses the attitudes of the urban and rural dwellers towards Setiu Wetlands conservation. The New Ecological Paradigm (NEP) scale is adopted to measure the degree of environmental concern. A series of factor analysis and regression is applied to analyze the urban-rural attitudes and three factors structure of attitudes to wetland conservation is suggested. The urban-rural residential variable is able to predict in part the overall NEP scores and element of anti-anthropocentrism, where the urban communities are more positive towards wetland conservation. Therefore, outreach efforts are suggested in the rural population.© 2016. The Authors. Published for AMER ABRA by e-International Publishing House, Ltd., UK. Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.Keywords: Setiu Wetlands conservation; urban-rural attitudes, New Ecological Paradigm
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Tao, Xiao Li, and Yong Ping Bai. "The Spatial-Temporal Change Pattern of Wetland in the Middle-Lower Yangtze River: A Case Study of Wuhu, Anhui." Applied Mechanics and Materials 513-517 (February 2014): 3228–32. http://dx.doi.org/10.4028/www.scientific.net/amm.513-517.3228.
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Wetlands play a number of roles in the environment, which are also considered the most biologically diverse of all ecosystems. Utilizing RS and the GIS software, remote datum were matched and classified. By these transactions, the temporal and spatial changes of wetland landscape are explored in Wuhu, combining qualitative analysis and quantitative methods. This paper analyzed the time-spatial revolution process which indicated that, firstly the area of wetland reduced rapidly from remote sensing image in 1988, 2001 and 2005, secondly the exterior of urban changed acutely and the interior were protected well in view of spatial pattern. Moreover, driving force factors were pointed out. Human activities, especially urbanization were the main causes of wetlands degradation. Simultaneity, the development of farming, the construction of infrastructure and nature were important factors. Owing to rapid economic development and urban sprawling, wetlands are encountering threaten to be converting to other land uses. Thus, the paper provides policy advices for wetland conservation and urban planning toward sustainable development.
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Dupuis-Desormeaux, Marc, Christina Davy, Amy Lathrop, Emma Followes, Andrew Ramesbottom, Andrea Chreston, and Suzanne E. MacDonald. "Colonization and usage of an artificial urban wetland complex by freshwater turtles." PeerJ 6 (August 8, 2018): e5423. http://dx.doi.org/10.7717/peerj.5423.
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Conservation authorities invest heavily in the restoration and/or creation of wetlands to counteract the destruction of habitat caused by urbanization. Monitoring the colonization of these new wetlands is critical to an adaptive management process. We conducted a turtle mark-recapture survey in a 250 ha artificially created wetland complex in a large North American city (Toronto, Ontario). We found that two of Ontario’s eight native turtle species (Snapping turtle (SN), Chelydra serpentina, and Midland Painted (MP) turtle, Chrysemys picta marginata) were abundant and both were confirmed nesting. The Blanding’s turtle (Emydoidea blandingii) was present but not well established. Species richness and turtle density were not equally distributed throughout the wetland complex. We noted SN almost exclusively populated one water body, while other areas of the wetland had a varying representation of both species. The sex ratios of both SN and MP turtles were 1:1. We tracked the movement of Snapping and Blanding’s turtles and found that most turtles explored at least two water bodies in the park, that females explored more water bodies than males, and that 95% of turtles showed fidelity to individual overwintering wetlands. We performed DNA analysis of two Blanding’s turtles found in the created wetlands and could not assign these turtles to any known profiled populations. The genetic data suggest that the turtles probably belong to a remnant local population. We discuss the implications of our results for connectivity of artificial wetlands and the importance of the whole wetland complex to this turtle assemblage.
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Brinkmann, Katja, Ellen Hoffmann, and Andreas Buerkert. "Spatial and Temporal Dynamics of Urban Wetlands in an Indian Megacity over the Past 50 Years." Remote Sensing 12, no. 4 (February 17, 2020): 662. http://dx.doi.org/10.3390/rs12040662.
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Asian megacities have attracted much scientific attention in the context of global urbanization, but few quantitative studies analyze wetland transformation in the rural–urban interface. With its rampant growth and transformation from a tree-lined “Garden City” to a busy megalopolis with often-blocked highways and large built-up areas, Bengaluru (Karnataka, S-India) is a good example for assessing how urbanization has led to the acute degradation of wetlands. We therefore investigated long-term land cover and wetland changes from 1965 to 2018 based on an object-based classification of multi-temporal Corona and Landsat images. To quantify and compare the dynamics of open water surfaces and vegetation, we defined the potential wetland areas (PWA) along the rural–urban gradient and linked our analyses to an index describing the degree of urbanization (survey stratification index (SSI)). During the five decades studied, built-up areas in the Bengaluru Urban district increased ten-fold, with the highest growth rate from 2014 to 2018 (+ 8% annual change). Patches of lake wetlands were highly dynamic in space and time, partly reflecting highly variable annual rainfall patterns ranging from 501 mm in 1965 to 1374 mm in 2005 and monsoon-driven alterations in the hydrologic regime. While water bodies and flooded areas shrunk from 64 km2 in 1965 to 55 km2 in 2018, in 1965, the total rural wetland area with an SSI > 0.5 was twice as high as in 2018. The rural–urban land cover pattern within potential wetland areas changed drastically during this period. This is reflected, for example, by a four-fold increase in the wetland area with an SSI of 0.3, as compared to a decline by 43% in wetland area with an SSI of 0.8. While, in urban areas, wetlands were mostly lost to construction, in areas with a rural character, open water bodies were mainly transformed into green space. The detected changes in urban wetlands were likely accompanied by ecological regime changes, triggering deteriorations in ecosystem services (ESS) which merit further research.
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Yang, Renfei, Fang Luo, Fu Ren, Wenli Huang, Qianyi Li, Kaixuan Du, and Dingdi Yuan. "Identifying Urban Wetlands through Remote Sensing Scene Classification Using Deep Learning: A Case Study of Shenzhen, China." ISPRS International Journal of Geo-Information 11, no. 2 (February 14, 2022): 131. http://dx.doi.org/10.3390/ijgi11020131.
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Urban wetlands provide cities with unique and valuable ecosystem services but are under great degradation pressure. Correctly identifying urban wetlands from remote sensing images is fundamental for developing appropriate management and protection plans. To overcome the semantic limitations of traditional pixel-level urban wetland classification techniques, we proposed an urban wetland identification framework based on an advanced scene-level classification scheme. First, the Sentinel-2 high-resolution multispectral image of Shenzhen was segmented into 320 m × 320 m square patches to generate sample datasets for classification. Next, twelve typical convolutional neural network (CNN) models were transformed for the comparison experiments. Finally, the model with the best performance was used to classify the wetland scenes in Shenzhen, and pattern and composition analyses were also implemented in the classification results. We found that the DenseNet121 model performed best in classifying urban wetland scenes, with overall accuracy (OA) and kappa values reaching 0.89 and 0.86, respectively. The analysis results revealed that the wetland scene in Shenzhen is generally balanced in the east–west direction. Among the wetland scenes, coastal open waters accounted for a relatively high proportion and showed an obvious southward pattern. The remaining swamp, marsh, tidal flat, and pond areas were scattered, accounting for only 4.64% of the total area of Shenzhen. For scattered and dynamic urban wetlands, we are the first to achieve scene-level classification with satisfactory results, thus providing a clearer and easier-to-understand reference for management and protection, which is of great significance for promoting harmony between humanity and ecosystems in cities.
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Hossain, Mohammad Zahid, Nishan Barua, and Nusrat Sultana. "Adaptive Urban Intervention in a Wetland: A Study from Hamidchar, Bangladesh." International Journal of Engineering and Technology 13, no. 1 (February 2021): 1–6. http://dx.doi.org/10.7763/ijet.2021.v13.1186.
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Over the last few decades the on-rushing surge of population created an urban structural instability across the under developing parts of the globe like Bangladesh. For instance, due to over population and urban sprawl the current development pattern of this country is culminating in filling up wetlands, changing the course of lakes, narrowing down in some cases killing rivers for urban development leaving the urban health in the face of a disastrous future. The concern for implementing an adaptive sustainable strategy that interacts with wetlands and rivers in the field of urban landscape should be prioritize as the burning question that need to be answered. This paper will be emphasizing on the strategies & guidelines to restore a riparian wetland through imputing wetland sensitive technique saving the riparian edge as well as creating a value of this wetland by suggesting some urban programs that will not only provide recreational value but also provide economic benefit to the local people. In this research there will be a sole intention to develop sustainable and riparian sensitive guidelines which would especially be applicable for riparian wetland development that leaves least impact on nature and promote the adjacent community life and wellbeing of urban health.
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Natarajan, Sai Kiran, Dharmappa Hagare, and Basant Maheshwari. "Constructed wetlands for improving stormwater quality and health of urban lakes." Water Supply 18, no. 3 (August 14, 2017): 956–67. http://dx.doi.org/10.2166/ws.2017.169.
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Abstract Urban lakes and wetlands are being more commonly used for the purpose of storing and treating stormwater. In some instances, a combination of both constructed wetlands and lakes are designed to further improve the efficiency of the system. The main aim of this paper is to compare the water quality between two urban stormwater lakes. A standalone lake system and a combined wetland/lake system were monitored for water quality. The results indicate that an integrated wetland and urban lake performs better than the urban lake alone. The improved performance was particularly significant in terms of physical parameters such as turbidity, suspended solids, total solids (TS) and nutrients (particularly nitrogen). The significance of the wetland in the integrated system is highlighted as it helped, on an average, to reduce the concentration of TS, ammonium and phosphate by 50%, 62% and 53%, respectively.
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Rojas Quezada, Carolina, and Felipe Jorquera. "Urban Fabrics to Eco-Friendly Blue–Green for Urban Wetland Development." Sustainability 13, no. 24 (December 13, 2021): 13745. http://dx.doi.org/10.3390/su132413745.
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In an urbanized world, the sustainability of cities will depend on their form and urban structure. In this sense, fabrics that are compact, dense, green, and suitable for non-motorized transport methods are more environmentally efficient. For the purpose of contributing new tools to the design, urban planning, and sustainability of nature in residential areas, this study characterizes the urban fabrics of six urban wetlands in the Latin American city of Concepción (Chile), which is known for its blue–green spaces. In a wetland city, we model urban patterns through spatial relationship using a statistical regression model (OLS—ordinary least squares) with the urban variables of density, distance, population, housing, highways, green areas, and building permits. Concepción shows predominantly low- to medium-density fabrics, and it is not integrated with the urban wetlands. In fact, it was observed that the residential areas do not take advantage of the blue–green spaces and that the urban fabrics do not favor proximity, with a transportation network that promotes the use of cars, leading to the wetlands being inaccessible and fragmented. However, as they are still surrounded by open spaces with abundant vegetation, there are highly feasible opportunities for the future development of blue–green infrastructure.
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Adeleke, Benjamin Oluwafemi. "Need for Emergency response to Wetlands Loss in Southwestern Nigeria: A Review." Ghana Journal of Geography 14, no. 3 (December 18, 2022): 90–114. http://dx.doi.org/10.4314/gjg.v14i3.4.
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Southwestern Nigeria's wetlands are assaulted, degraded, and lost, especially to agricultural development and urban expansions, while the rural wetlands losses are due to agriculture but temporal in nature, loss to urban developments are permanent. To examine the extent, influence, and potential of the degradation, the review covered the six states of the region, revealing losses due to wetlands destruction in the region between 1965 and 2019. Wetlands in Lagos reduced from 708.96ha (52.68%) in 1965 to 7.10ha (0.53%) in 2005, Eleyele Wetland in Oyo State, (Riparian), reduced consistently from (1.25 km2) in 1984 to (0.98 km2) 1994, (0.70 km2) 2004 and finally (0.42 km2) in 2014. Eriti forested wetlands of Ogun State lost about 45.32% between 1972 and 2015; in Ondo State, Akure South Local Government Area Wetlands decreased from 98.90 km2 (30.13%) in 1999 to 90.33 km2 in 2009 (27.52%); Ilesa wetlands, in Osun State decreased from 258 hectares to 89 hectares between 1986 and 2002. The above scenarios in the region imply that in a short while, the wetlands would be completely lost, most importantly to the uncontrolled urban developments. Therefore, there is an urgent need for all hands to be on deck to protect wetlands by considering them as endangered ecosystems.
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Sinthumule, Ndidzulafhi Innocent, and Khathutshelo Hildah Netshisaulu. "Wetland Resource Use and Conservation Attitudes of Rural vs. Urban Dwellers: A Comparative Analysis in Thohoyandou, Limpopo Province, South Africa." Water 14, no. 8 (April 15, 2022): 1290. http://dx.doi.org/10.3390/w14081290.
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Although wetlands provide a variety of goods and services to people and ecosystems, they are the most threatened ecosystem in the world because they are easily degraded. Thus, efforts to protect the remaining wetlands are critical if this resource is to continue providing environmental, cultural, and economic goods and services. Central to the conservation and management of wetlands is understanding the attitudes of the people bordering wetlands. This study aimed to analyse wetland resource use and conservation attitudes of urban vs. rural dwellers of Thohoyandou, Limpopo Province, South Africa. Interview-administered questionnaires and observation were the methods used for data collection. Systematic random sampling was used to obtain a sample of 282 in urban and 312 households in rural areas. Descriptive statistics (frequencies, percentages) were used to summarize the data. Chi-square (χ2) tests were applied using Microsoft Excel (Microsoft Corporation, Redmond, Washington, WA, USA) in order to determine whether responses occurred with equal probability. Differences were considered to be significant at p ≤ 0.05. The study found that wetlands are more important in the lives and livelihoods of people in rural areas (92.9%) compared with urban areas (26.6%) of Thohoyandou. Human land use activities in wetlands (especially cultivation and infrastructural development) have degraded and destroyed wetlands—particularly those located in urban areas. The attitudes of respondents were generally positive both in urban and rural areas regarding the need for conservation and rehabilitation/restoration of wetlands. The study concluded that positive attitudes alone are insufficient to save and protect the wetlands. The responsible authorities should implement existing legislation to complement the positive attitudes of people and, importantly, they should work with communities towards the conservation of wetlands.
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Mao, Qian, Chencan Liao, Zhaolu Wu, Wenbo Guan, Wenda Yang, Yuqin Tang, and Gang Wu. "Effects of Land Cover Pattern Along Urban-Rural Gradient on Bird Diversity in Wetlands." Diversity 11, no. 6 (May 31, 2019): 86. http://dx.doi.org/10.3390/d11060086.
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Wetlands play an important role in the feeding, breeding, and lives of birds. However, available habitats for bird species are changing due to intensifying human activity, especially in the context of China’s mass urbanization. Urban sprawl has taken over the wetlands along the lakes in the past decades, which places tremendous pressure on wetland ecosystems and, therefore, on bird communities. However, the ways urban land cover pattern along the urban-rural gradient affects bird communities is still unclear. To investigate the influence of land cover pattern on the α and β diversity of birds in the urban-rural gradient we chose 31 sites distributed within the wetlands around the Dianchi Lake in Yunnan, China. We calculated the species richness to indicate α diversity and used the Morisita–Horn index to indicate β diversity. Meanwhile, we assessed the land cover pattern of each site by measuring the proportion of emergent plants, floating plants, submerged plants, ponds, forests, lawns, roads, agricultural lands and built lands in a quadrat of 1 square kilometer. Simple linear regressions, model selection, and an averaging approach based on corrected Akaike information criterion (AICc) were used to test the effects of land cover pattern on bird diversity. Using one-way ANOVA and Tukey’s HSD (honestly significant difference) test, we compared the difference between α and β diversity, respectively, along the urban-rural gradient. Based on our analyses, urban and suburban wetland birds were significantly homogeneous. The community structure in rural wetlands, however, was significantly different from that of the suburban and urban areas. According to our research, the land cover patterns that influenced bird species richness were the built lands acreage, submerged plants acreage, ponds acreage, and the edge density of emergent plants. Meanwhile, of these variables, the built lands acreage, ponds acreage and edge density of emergent plants were significantly different in urban, suburban, and rural wetlands. Therefore, to maintain high biodiversity in wetlands affected by urbanization, we must pay more attention to the land cover patterns.
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Frey, Elaine F., Marissa B. Palin, Patrick J. Walsh, and Christine R. Whitcraft. "Spatial Hedonic Valuation of a Multi-use Urban Wetland in Southern California." Agricultural and Resource Economics Review 42, no. 2 (August 2013): 387–402. http://dx.doi.org/10.1017/s1068280500004433.
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Most of Southern California's wetlands have disappeared despite being critical ecosystems with many valuable attributes. Many of the wetlands that remain are in relatively urban areas, are severely degraded, and may not function properly. Using hedonic spatial error models, we measure the economic value of living near an urban multi-use wetland in Long Beach, California. Both sales prices and estimated values are used in the analysis. Results show that proximity to wetlands increases residential property values in the focus area. This analysis provides important information for policymakers to justify ongoing restoration projects and prevent further degradation of urbanized natural resources.
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Bin, Okmyung, and Stephen Polasky. "Evidence on the Amenity Value of Wetlands in a Rural Setting." Journal of Agricultural and Applied Economics 37, no. 3 (December 2005): 589–602. http://dx.doi.org/10.1017/s1074070800027103.
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This study uses a hedonic property price method to estimate how wetlands affect residential property values in a rural area. The study utilizes wetland inventory data coupled with extensive property sales records between January 2000 and September 2004 from Carteret County, NC. Our results indicate that i) a higher wetland percentage within a quarter mile of a property, ii) closer proximity to the nearest wetland, and iii) larger size of the nearest wetland are associated with lower residential property values. These results contrast with previous hedonic studies that use data from urban areas, which found positive associations between wetlands and property values. The amenity value of wetlands appears to depend at least as much on the characteristics of the area being considered as it does on the characteristics of the wetlands.
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Li, Zhaobin, Lei Ma, Dongmei Gou, Qianqian Hong, Leungkam Fai, and Bo Xiong. "The Impact of Urban Development on Wetland Conservation." Sustainability 14, no. 21 (October 24, 2022): 13747. http://dx.doi.org/10.3390/su142113747.
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Wetland is an integrated ecosystem which includes ecosystems such as hydrology, soil, vegetation, and biological environments. At present, the urbanization rate of China’s national economic development process is rapidly increasing, and by the end of 2021, the urbanization rate of China’s resident population will be 64.72%. This paper analyzes the hydrological effects of urbanization, the impact of water resources, climate change, and biodiversity on wetland ecosystems, and also analyzes the role of wetlands on the ecological environment, especially in terms of ecological and cultural values. The economic and social benefits of the whole society are also analyzed. The ecological and social benefits of urban wetlands have made their conservation and sustainable development increasingly important worldwide. Based on the current situation of China’s urban wetland protection and restoration, we put forward countermeasures and suggestions for China’s urban wetland protection. This is conducive to promoting the sustainable development of the urban wetland ecosystem, promoting the operation of the market, realizing the optimal allocation of ecological resources, improving the benefits of ecological environmental protection, and promoting the coordinated development of the ecological environment. This paper provides a reference for the better development of wetland conservation under urbanization development conditions.
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Shutes, B., J. B. Ellis, D. M. Revitt, and L. N. L. Scholes. "Constructed wetlands in UK urban surface drainage systems." Water Science and Technology 51, no. 9 (May 1, 2005): 31–37. http://dx.doi.org/10.2166/wst.2005.0281.
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This paper presents the outcome of an inventory of planted wetland systems in the UK which are classified according to land use type and are all examples of sustainable drainage systems. The introduction of constructed wetlands to treat surface runoff essentially followed a 1997 Environment Agency for England and Wales report advocating the use of “soft engineered” facilities including wetlands in the context of sustainable development and Agenda 21. Subsequently published reports by the UK Construction Industry Research and Information Association (CIRIA) have promoted the potential benefits to both developer and the community of adopting constructed wetlands and other vegetated systems as a sustainable drainage approach. In addition, the UK Environment Agency and Highways Agency (HA) have recently published their own design criteria and requirements for vegetative control and treatment of road runoff. A case study of the design and performance of a constructed wetland system for the treatment of road runoff is discussed. The performance of these systems will be assessed in terms of their design criteria, runoff loadings as well as vegetation and structure maintenance procedures. The differing design approaches in guidance documents published in the UK by the Environment Agency, CIRIA and HA will also be evaluated.
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Hettiarachchi, Missaka, Kusum Athukorale, Suren Wijekoon, and Ajith de Alwis. "Urban wetlands and disaster resilience of Colombo, Sri Lanka." International Journal of Disaster Resilience in the Built Environment 5, no. 1 (March 4, 2014): 79–89. http://dx.doi.org/10.1108/ijdrbe-11-2011-0042.
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Purpose – This paper aims to present a long-term research project to understand the nature and extent of degradation in a selected segment of the Colombo Flood Detention Area (CFDA) wetlands. It qualitatively explores the gradual process of change in watersheds and the wetland ecology affecting flood control services, thereby leading to full-blown disasters. It underlines the importance of protecting ecosystem health of urban ecological features for strengthening the disaster resilience of cities. Design/methodology/approach – Through analyzing the long-term change of landscape level parameters, water-quality, vegetation and soil quality, the authors emphasize the potential of an outright ecological regime change and the effects on ecosystem services of the wetlands. Findings – Colombo is a city surrounded by a large and interconnected system of natural wetlands that provides a valuable flood control service. The rapid and partly ad hoc urbanization in the past 15-25 years has caused a steady degradation in the wetlands that severely threatens the ecosystem services. It was found that the native, grass-dominated marshy habitat of the wetland is rapidly transforming into a habitat with shrubs and small trees (44 percent of the extent). Typical peaty soil in the marsh has also changed into a semi-mineral soil. Both changes result in a significant reduction in water-holding capacity of the wetland, thus increasing the flood frequency. Practical implications – These ecological changes have undermined the effectiveness of the repeated cost-intensive engineering measures taken by the authorities to contain floods. Originality/value – CFDA had not been studied previously in an ecosystem services and disaster resilience perspectives. The ecological and hydrological aspects have been studied separately without integration.
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Ahn, Changwoo, and Stephanie Schmidt. "Designing Wetlands as an Essential Infrastructural Element for Urban Development in the era of Climate Change." Sustainability 11, no. 7 (March 31, 2019): 1920. http://dx.doi.org/10.3390/su11071920.
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The increasing development of urban infrastructure has led to the significant loss of natural wetlands and their ecosystem services. Many novel urban development projects currently attempt to incorporate environmental sustainability, cross-disciplinary collaboration, and community engagement into the intricate challenges we all face in an era of climate change. This paper aims to communicate several key findings on design elements that can be adopted or incorporated in the design of created wetlands as infrastructural elements. Three major design elements—microtopography, hydrologic connectivity, and planting diversity—are presented, and their relations to restoring ecosystem services of urban wetlands, in particular water and habitat quality, are discussed. These design elements can be easily adopted or incorporated in the planning, designing, and construction stages of urban development. The success of urban infrastructure projects may require both better communication among stakeholders and a great deal of community engagement. The Rain Project, a floating wetland project on an urban college campus, demonstrates the role of interdisciplinary collaboration and community engagement as a model for sustainable stormwater management, a critical part of today’s urban development. Further efforts should be made to advance the science of designing urban wetlands and its communication to transform cultural attitudes toward sustainable urban development.
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Hassan, Suziana, Søren B. Olsen, Syamsul Herman Mohammad Afandi, and Bo J. Thorsen. "Environmental Attitudes on Setiu Wetlands, Malaysia." Asian Journal of Quality of Life 3, no. 11 (May 21, 2018): 59. http://dx.doi.org/10.21834/ajqol.v3i11.122.
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This study addresses the attitudes of the urban and rural dwellers towards Setiu Wetlands conservation. The New Ecological Paradigm (NEP) scale is adopted to measure the degree of environmental concern. A series of factor analysis and regression is applied to analyze the urban-rural attitudes and to suggest three factors structure of attitudes to wetland conservation. The urban-rural residential variable is able to predict in part the overall NEP scores and element of anti-anthropocentrism which suggesting the urban communities are more positive towards wetland conservation. Hence, further outreach efforts in rural population are worthwhile to raise conservation awareness.Keywords: Setiu Wetlands conservation; urban-rural attitudes, New Ecological Paradigm.eISSN 2398-4279 © 2018. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. https://doi.org/10.21834/ajqol.v3i11.122
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Xu, Erqi, and Yimeng Chen. "Modeling Intersecting Processes of Wetland Shrinkage and Urban Expansion by a Time-Varying Methodology." Sustainability 11, no. 18 (September 11, 2019): 4953. http://dx.doi.org/10.3390/su11184953.
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Continuous urban expansion worldwide has resulted in significant wetland degradation and loss. A limited number of studies have addressed the coupling of wetland and urban dynamics, but this relationship remains unclear. In this study, a time-varying methodology of predicting wetland distribution was developed to support decision-making. The novelty of the methodology is its ability to dynamically simulate wetland shrinkage together with urban expansion and reveal conflicts and potential tradeoffs under different scenarios. The developed methodology consists of three modules: a historical change detection of wetland and urban areas module, a spatial urban sprawl simulation and forecasting module that can accommodate different development priorities, and a wetland distribution module with time-varying logistic regression. The methodology was applied and tested in the Tonghu Wetland as a case study. The wetland and urban extents presented a spatially intersecting shift, where wetlands lost more than 40% of their area from 1977 to 2017, while urban areas expanded by 10-fold, threatening wetlands. The increase in the relative importance metric of the time-varying regression model indicated an enhanced influence of urban expansion on the wetland. An accuracy assessment validated a robust statistical result and a good visual fit between spatially distributed wetland occurrence probabilities and the actual distribution of wetland. Incorporating the new variable of urban expansion improved modeling performance and, particularly, realized a greater ability to predict potential wetland loss than provided by the traditional method. Future wetland loss probabilities were visualized under different scenarios. The historical trend scenario predicted continuously expanding urban growth and wetland shrinkage to 2030. However, a specific urban development strategy scenario was designed interactively to control the potential wetland loss. Consideration of such scenarios can facilitate identifying tradeoffs to support wetland conservation.
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Saxena, Shalini. "CLEAN DEVELOPMENT MECHANISM AND CARBON CYCLING OF SEWAGE WASTE BY CONSTRUCTED WETLANDS." International Journal of Research -GRANTHAALAYAH 10, no. 4 (May 17, 2022): 209–15. http://dx.doi.org/10.29121/granthaalayah.v10.i4.2022.4517.
Full textAbstract:
Wetlands, either constructed or natural, offer a cheaper and low-cost alternative technology for wastewater treatment. A constructed wetland system that is specifically engineered for water quality improvement as a primary purpose is termed as a ‘Constructed Wetland Treatment System’ (CWTS). In the past, many such systems were constructed to treat low volumes of wastewater loaded with easily degradable organic matter for isolated populations in urban areas. However, widespread demand for improve in water quality, and water reclamation and reuse, is currently the driving force for the implementation of CWTS all over the world. Recent concerns over wetland losses have generated a need for the creation of manmade wetlands, which are intended to emulate the functions and values of natural wetlands that have been destroyed. Natural characteristics are applied to CWTS with emergent macrophyte stands that duplicate the physical, chemical and biological processes of natural wetland systems. The number of CWTS in use has very much increased in the past 50 years. The use of constructed wetlands is gaining rapid interest. Most of these systems cater for tertiary treatment from towns and cities. They are larger in size, usually using surface-flow system to remove low concentration of nutrient (N and P) and suspended solids. However, in some countries, these constructed wetland treatment systems are usually used to provide secondary treatment of domestic sewage for village populations. These constructed wetland systems have been seen as an economically attractive, energy-efficient way of providing high standards of wastewater treatment.
Typically, wetlands are constructed for one or more of four primary purposes: creation of habitat to compensate for natural wetlands converted for agriculture and urban development, water quality improvement, flood control, and production of food and fiber (constructed aquaculture wetlands). In present research the sewage water is treated by constructing Horizontal sub – surface flow constructed wetland, and reed grass is used as vegetation to treat waste and make the sewage waste water clean.
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Ji, Wei. "REMOTELY-SENSED URBAN WET-LANDSCAPES: AN INDICATOR OF COUPLED EFFECTS OF HUMAN IMPACT AND CLIMATE CHANGE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (June 23, 2016): 915–18. http://dx.doi.org/10.5194/isprs-archives-xli-b8-915-2016.
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This study proposes the concept of urban wet-landscapes (loosely-defined wetlands) as against dry-landscapes (mainly impervious surfaces). The study is to examine whether the dynamics of urban wet-landscapes is a sensitive indicator of the coupled effects of the two major driving forces of urban landscape change – human built-up impact and climate (precipitation) variation. Using a series of satellite images, the study was conducted in the Kansas City metropolitan area of the United States. A rule-based classification algorithm was developed to identify fine-scale, hidden wetlands that could not be appropriately detected based on their spectral differentiability by a traditional image classification. The spatial analyses of wetland changes were implemented at the scales of metropolitan, watershed, and sub-watershed as well as based on the size of surface water bodies in order to reveal urban wetland change trends in relation to the driving forces. The study identified that wet-landscape dynamics varied in trend and magnitude from the metropolitan, watersheds, to sub-watersheds. The study also found that increased precipitation in the region in the past decades swelled larger wetlands in particular while smaller wetlands decreased mainly due to human development activities. These findings suggest that wet-landscapes, as against the dry-landscapes, can be a more effective indicator of the coupled effects of human impact and climate change.
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Ji, Wei. "REMOTELY-SENSED URBAN WET-LANDSCAPES: AN INDICATOR OF COUPLED EFFECTS OF HUMAN IMPACT AND CLIMATE CHANGE." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (June 23, 2016): 915–18. http://dx.doi.org/10.5194/isprsarchives-xli-b8-915-2016.
Full textAbstract:
This study proposes the concept of urban wet-landscapes (loosely-defined wetlands) as against dry-landscapes (mainly impervious surfaces). The study is to examine whether the dynamics of urban wet-landscapes is a sensitive indicator of the coupled effects of the two major driving forces of urban landscape change – human built-up impact and climate (precipitation) variation. Using a series of satellite images, the study was conducted in the Kansas City metropolitan area of the United States. A rule-based classification algorithm was developed to identify fine-scale, hidden wetlands that could not be appropriately detected based on their spectral differentiability by a traditional image classification. The spatial analyses of wetland changes were implemented at the scales of metropolitan, watershed, and sub-watershed as well as based on the size of surface water bodies in order to reveal urban wetland change trends in relation to the driving forces. The study identified that wet-landscape dynamics varied in trend and magnitude from the metropolitan, watersheds, to sub-watersheds. The study also found that increased precipitation in the region in the past decades swelled larger wetlands in particular while smaller wetlands decreased mainly due to human development activities. These findings suggest that wet-landscapes, as against the dry-landscapes, can be a more effective indicator of the coupled effects of human impact and climate change.
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Saxena, Shalini. "EFFICACY OF PHRAGMITE KARKA PLANT IN CONSTRUCTED WETLAND SYSTEM." International Journal of Research -GRANTHAALAYAH 3, no. 9SE (September 30, 2015): 1–5. http://dx.doi.org/10.29121/granthaalayah.v3.i9se.2015.3177.
Full textAbstract:
Wetlands, either constructed or natural, offer a cheaper and low-cost alternative technology for wastewater treatment. A constructed wetland system that is specifically engineered for water quality improvement as a primary purpose is termed as a ‘Constructed Wetland Treatment System’ (CWTS). In the past, many such systems were constructed to treat low volumes of wastewater loaded with easily degradable organic matter for isolated populations in urban areas. However, widespread demand for improved receiving water quality, and water reclamation and reuse, is currently the driving force for the implementation of CWTS all over the world. Recent concerns over wetland losses have generated a need for the creation of wetlands, which are intended to emulate the functions and values of natural wetlands that have been destroyed. Natural characteristics are applied to CWTS with emergent macrophyte stands that duplicate the physical, chemical and biological processes of natural wetland systems. The number of CWTS in use has very much increased in the past few years. The use of constructed wetlands is gaining rapid interest. Most of these systems cater for tertiary treatment from towns and cities. They are larger in size, usually using surface-flow system to remove low concentration of nutrient (N and P) and suspended solids. However, in some countries, these constructed wetland treatment systems are usually used to provide secondary treatment of domestic sewage for village populations. These constructed wetland systems have been seen as an economically attractive, energy-efficient way of providing high standards of wastewater treatment by the help of Phragmite karka plant.
Typically, wetlands are constructed for one or more of four primary purposes: creation of habitat to compensate for natural wetlands converted for agriculture and urban development, water quality improvement, flood control, and production of food and fiber.
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Li, Ji Guang, Hui Sun, Yi Bin Ren, Nan Qi Ren, Chun Wen Yang, Chun Sheng Zuo, Zhi Min Jin, and Yan Qiu Shao. "Ecological Safety Analysis and Statistics Measures of Wuyiling Wetland in Yichun in Northeast China." Advanced Materials Research 418-420 (December 2011): 2298–301. http://dx.doi.org/10.4028/www.scientific.net/amr.418-420.2298.
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Ecological Safety play in the wetland to maintain ecosystem equilibrium, ecosystems in wetland maintaining the safety of the ecological functions of wetlands play a huge role. Articles by SPSS statistical software, using factor analysis method and clustering analysis method to select a number of indicators before and after the incident on Wuyiling wetlands were studied. The results show that: the highest level of ecological security in the eastern region, the worst safety in the western region. The best scores of the Eastern biological factors; Eastern stability of the strongest water pollution incident; the safety of northern wetlands in water pollution after a downward trend. That pollution directly affects the safety of urban wetland.
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Eaton, T. T., and C. Yi. "Hydroperiod and hydraulic loading for treatment potential in urban tidal wetlands." Hydrology and Earth System Sciences Discussions 6, no. 1 (January 30, 2009): 589–625. http://dx.doi.org/10.5194/hessd-6-589-2009.
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Abstract. Conventional methods of estimating water quality improvement due to wetland treatment are not well suited to the dynamic water level and wetted area fluctuations observed in coastal settings. We present a new method to quantify hydroperiod and hydraulic loading at different elevations in a coastal wetland profile in which the principal inflows and outflows are due to tides. We apply our method to an urban coastal setting (part of the New York-New Jersey Harbor Estuary) where a major water quality problem persists due to fecal coliform contamination from combined sewer overflow (CSO) discharges. Based on three types of simplified hydrograph, we show how such an approach and conceptual model of a terraced tidal wetland with constant mean slope can be used to assess hydrologic constraints for wetland vegetation species and the potential treatment effectiveness for adjacent impaired coastal waters. Resulting hydroperiods and hydraulic loading values decrease approximately exponentially with elevation along the wetland profile with considerable variation in overall slope depending on the hydrograph pattern. Application of a first-order contamination reduction model using our calculated hydraulic loadings indicates that such tidal treatment wetlands could reduce average fecal coliform concentrations in the range of 27% to 94% depending on the pattern of water level fluctuation, wetland surface elevation and vegetation density. Our analysis shows the performance potential for tidal wetlands to treat adjacent coastal waters. Restoration of existing salt marshes, and construction of new tidal wetlands would therefore be a promising part of an ecohydrologic strategy to improve water quality in contaminated urban coastal settings like the New York-New Jersey Harbor Estuary.
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Hettiarachchi, Missaka, Jayani Anurangi, and Ajith De Alwis. "Characterisation and Description of Surface Water Quality in the Threatened Urban Wetlands around the City of Colombo." Journal of Wetlands Ecology 5 (December 28, 2011): 10–19. http://dx.doi.org/10.3126/jowe.v5i0.2831.
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Colombo is a city surrounded by a large and interconnected system of natural wetlands. These wetlands which have historically provided a range of water services to the city are now believed to be threatened by degradation due to the recent changes in the urbanization patterns and urban lifestyle in Colombo. This paper presents a study on the current state and recent trends in surface water quality in a selected segment of these wetlands. The study was carried out as a part of a broader multidisciplinary research. The paper consists of a historical analysis of trends in surface water quality parameters and situation analysis of short term spatial and temporal water quality variation in the study area. The research identified that water quality parameters indicating domestic wastewater related pollution showed an increasing trend during the study period. BOD, Phosphates and Fecal Coliform were recorded in levels exceeding the accepted ambient water quality standards. Concentrations of several heavy metals were also above the ambient water quality standards. A distinct difference was observed in water quality between peripheral areas and internal water ways of the wetland. All evidence directs towards severe water quality degradation in the wetland dominated by domestic waste discharges and scattered solid waste dumps. This condition may lead to a nutrient enrichment of the wetland and cause biological and physical responses that may affect adversely on the water services provided. Key words: Water Quality; Urban Wetlands; Wetland Nutrient Enrichment; Water Services; Urban Water Pollution DOI: http://dx.doi.org/10.3126/jowe.v5i0.2831 J Wet Eco 2011 (5): 10-19
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Bourgues, S., and B. T. H. Hart. "Nitrogen removal capacity of wetlands: sediment versus epiphytic biofilms." Water Science and Technology 55, no. 4 (February 1, 2007): 175–82. http://dx.doi.org/10.2166/wst.2007.107.
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Wetlands are important sinks for nutrients and constructed wetlands are current practice for stormwater treatment. For nitrogen, the main removal process is denitrification (microbial reduction of nitrate to nitrogen gas). The bacteria responsible for this process are mostly found in the sediments and in epiphytic biofilms growing on wetland macrophytes. This paper reports on a project which aimed at measuring denitrification potential in sediments and epiphyton in urban wetlands. This study showed that wetland sediments could support high rates of denitrification. Interestingly, the most polluted of the wetlands studied had the highest denitrification potential. The management implication from this result is that indicators of pollution, such as hydrocarbon levels, will not necessarily reflect the ability of a wetland to denitrify. Two of the wetlands were studied in more detail. Here the denitrification potential of the epiphyton on dominant macrophytes and sediments were measured. The results indicated that the potential denitrification activity of the epiphyton was comparable to those measured in the sediments. Hence, biofilms could play a significant part in removing nitrogen loads. This work contributes to a better knowledge of the functioning of wetlands. This will lead to improved design and management of wetlands used for treating stormwater.
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Shahjahan, Abu Taib Mohammed, Khandaker Shabbir Ahmed, and Ismail Bin Said. "Study on Riparian Shading Envelope for Wetlands to Create Desirable Urban Bioclimates." Atmosphere 11, no. 12 (December 12, 2020): 1348. http://dx.doi.org/10.3390/atmos11121348.
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Climate change and rapid urbanization are adversely affecting the urban environment by exacerbating the widely reported urban heat island effect in Dhaka, Bangladesh. Two wetland areas with variable riparian shadings in the warm-humid conditions of urban Dhaka were investigated through field campaigns on microclimatic parameters for their cooling potential on the surrounding urban fabric. It was observed that an inversion layer of fully saturated air develops over the water surface of wetland, suppressing evaporation from the wetland water surface layer, which was effectively reducing the heat exchange between the water surface and the air layer above it through its action as an insulating vapor blanket. Due to this effect, the wetland was unable to render as a source of coolth for the surrounding overheated urban area. This effect of the inversion layer was more pronounced in the urban wetland without riparian shading either by the urban form or tree canopy. A multiphysics simulation study conducted on the selected urban wetlands indicates the effect of differential shading pattern on the relation between fetch and inversion layer thickness. This research hypothesizes that the wetland can act as an urban adaption measure against the urban heat island effect by potentially transforming them into an urban cooling island (UCI) towards a favorable urban bioclimate.