Analysis on Ecological Benefits of Urban Wetlands and Protection Measures with a Case of Nansha Wetland

Nansha wetland plays a crucial role in ecological balance of the Pearl River Delta or even Guangzhou. The research, based on researches available, analyzed ecological benefits of Nansha wetland and proposed protection measures in order to better protect urban wetlands and achieve sustainable development of ecological resources of Nansha wetland.

Quantifying driving forces of urban wetlands change in Beijing City

The decision tree and the threshold methods have been adopted to delineate boundaries and features of water bodies from LANDSAT images. After a spatial overlay analysis and using a remote sensing technique and the wetland inventory data in Beijing, the water bodies were visually classified into different types of urban wetlands, and data on the urban wetlands of Beijing in 1986, 1991, 1996, 2000, 2002, 2004 and 2007 were obtained. Thirteen driving factors that affect wetland change were selected, and gray correlation analysis was employed to calculate the correlation between each driving factor and the total area of urban wetlands. Then, six major driving factors were selected based on the correlation coefficient, and the contribution rates of these six driving factors to the area change of various urban wetlands were calculated based on canonical correlation analysis. After that, this research analyzed the relationship and mechanism between the main driving factors and various types of wetlands. Five conclusions can be drawn. （1） The total area of surface water bodies in Beijing increased from 1986 to 1996, and gradually decreased from 1996 to 2007. （2） The areas of the river wetlands, water storage areas and pool and culture areas gradually decreased, and its variation tendency is consistent with that of the total area of wetlands. The area of the mining water areas and wastewater treatment plants slightly increased. （3） The six factors of driving forces are the annual rainfall, the evaporation, the quantity of inflow water, the volume of groundwater available, the urbanization rate and the daily average discharge of wastewater are the main factors affecting changes in the wetland areas, and they correlate well with the total area of wetlands. （4） The hydrologic indicators of water resources such as the quantity of inflow water and the volume of groundwater are the most important and direct driving forces that affect the change of the wetland area. These factors have a combined contribution rate of 43.94%. （5） Climate factors such as rainfall and evaporation are external factors that affect the changes in wetland area, and they have a contribution rate of 36.54%. （6） Human activities such as the urbanization rate and the daily average quantity of wastewater are major artificial driving factors. They have an influence rate of 19.52%.

Importance of Urban Wetland Parks under the Development of Green Healthy Cities:A Case Study of Nanjing City

Wetlands are widely distributed all over the world,and have many wildlife resources,which are the main pieces of the puzzle for natural resource conservation and sustainable development on earth and have important irreplaceability.In this paper,through questionnaire survey,field research,literature review,etc.,importance weight analysis was conducted by using principal component analysis,and field survey and questionnaire were carried out to collect data on ecological environment function,environmental protection function,landscape beautification function,disaster prevention and mitigation function of urban wetlands.The problems in wetland parks of Nanjing were discussed,such as lack of awareness of landscape planning,deficient late management of wetland parks,weak ability of sustainable development,and unreasonable landscape layout and function.Finally,corresponding solutions were proposed,such as adhering to the planning and design of urban wetland parks with green as the base and health as the basis,persisting in the construction of a wetland system with high biodiversity and near-natural characteristics,adhering to the principle of sustainable development,adopting the construction idea of symbiosis and circulation of urban wetland parks,strengthening education and publicity work,and paying attention to the organic combination of system protection and coordinated construction.The research can build a new development direction for the model of urban wetland parks and green healthy cities,and provide theoretical support for urban sustainable construction.

Changes of Urban Wetland Landscape Pattern and Impacts of Urbanization on Wetland in Wuhan City

In this study,remote sensing data of Wuhan City,Hubei Province,China in 1996-2001 were selected to ex-tract wetland landscape information.Several landscape indices were used to evaluate the changes of landscape pattern within the five years,including patch number,patch density,patch fractal dimension,landscape diversity,dominance,evenness,and fragmentation indexes.Then,transformation probabilities of wetland landscapes into non-wetland land-scapes were calculated based on Markov Model,and on these grounds the relationship between changes of wetland landscape pattern and urban construction was analyzed.The results showed that fragmentation degree of all wetland types increased,lake area declined,and dominance of natural wetland decreased.The reasons for these results were mainly because of urban construction.According to the features of abundant wetland in Wuhan City,we suggested that protection of wetland landscape should cooperate with urban construction,which means wetland should become im-portant part of urban landscape.

Application of Landscape Plants in the Huaxi National Urban Wetland Park

The current situation of plants in Shilihe Beach of the Huaxi National Urban Wetland Park was investigated and analyzed. The results show that there are about 181 species of landscape plants in this park, of which arbors and shrubs are dominant. Various species of plants grow differently because of different types of artificial maintenance. The overall partition of the wetland park dose not follow the features of a river-type wetland and is not clear. In this park, the planting area of hygrophyte is far less than that of terrestrial plants. As a result, the wetland park is evolving into a public garden. It is suggested that the overall design of the park should be conducted in accordance with site characteristics and resources, and the park should be developed and built reasonably based on the principle that the ecology is a priority.

Progress and Prospect of Studies on Landscape Health of Urban Wetland Park

Rapid urbanization and increasing attention on the construction of wetland park have contributed to the increasing research fruits of urban wedand park.This paper,on the basis of sorting out literatures on urban wedand park from 2004 to 2015,analyzed the research contents and proposed the prospects.The research contents focused on concept of urban wedand park and landscape health,influence factors,ecological health,landscape health,and evaluation standard.It was found that the research methods vaned,quantitative and qualitative researches were combined;there were rich data sources,dynamic and static researches were integrated;theories lagged behind practices,and the research scale was limited.Therefore,the theoretical system must be improved from the perspective of philosophy and management science;national,regional and other large-scale analysis must be valued to expand the research scale;influence factors were analyzed from multiple perspectives.

Optimizing Rank of Landscape Planning Works of Urban Wetland Park

Classifying and ranking the huge amounts of landscape planning works of urban wetland park is always difficult due to the multi-functions （ecological, leisure, educational and disaster prevention） of the urban wetland park. Therefore, an optimizing rank system is urgently needed. Analytic Hierarchy Process （AHP） and Technique for Order Preference by Similarity to Ideal Solution （TOPSIS） models were used to rank the planning works of 30 urban wetland park based on four mainly factors, which included landscape ecological planning, landscape planning, ecological planning and economic planning. The study indicated that the AHP- TOPSIS model had good discrimination in the classification and ranking of landscape planning works of urban wetland park and it was also applicable to the planning works of other urban greenbelts.

Floral Diversity Status in Urban Coastal Wetland &Associated Coastal Ecosystems of Crow Island Mattakkuliya, Sri Lanka

Colombo is the capital of Sri Lanka and the only wetland city in South Asia under the Ramsar Convention. Crow Island Beach Park and associated coastal area belong to the Colombo urban coastal wetland ecosystems. Crow Island wetland contributes diverse habitats for numerous flora and fauna species. The present study was conducted to assess the status of floral diversity in the Crow Island Beach Park and associated coastal ecosystem during the months of August to October 2021. Study area is divided in to three sites (A, B, C). Line transects method and field observations were used in the study. This coastal wetland consists of mosaic of five major vegetation types: Herbaceous, tree, shrub, creeper, grass and other than that marine algae namely Chaetomorpha antennina, Rhizoclonium africanum, Ulva compressa belonging to chlorophyta (green algae) and Grateloupia lithophila belonging to rhodophyta (red algae) were found in the study area. A total number of 102 flora species belonging to 50 families were recorded from the study area. There were two true mangrove species and 16 mangrove associated species in the study sites. Out of the 102 plant species 46 were recognized and documented as plants with medicinal values. Shannon-Wiener diversity indexes for mangrove and mangrove associated species were recorded as 2.378, 2.304 and 1.676 in site A, B and C respectively. Simpson’s diversity index for mangrove and mangrove associated species was recorded as 0.889, 0.874 and 0.735 respectively in site A, B and C and Jaccard index of similarity between three study sites showed high values ranging from 41% to 69% for mangrove and mangrove associated species.

Phytoplankton Diversity of a Demineralized Urban Wetland of Meghalaya State of Northeast India:The Spatio-temporal Variations and the Role of Abiotic Factors

The authors analyze phytoplankton diversity of a small urban wetland of Meghalaya to assess biodiversity and limnology interest of small water bodies.This“slightly acidic-circumneutral,demineralized and soft water”subtropical wetland reveals diverse phytoplankton(64 species),indicates high desmid richness and highlights the speciose littoral constellations of up to 55-58 species per sample.Phytoplankton comprises dominant quantitative component of net plankton and registers Charophyta dominance;Chlorophyta>Bacillariophyta>Dinozoa>Chrysophyta>Cyanobacteria depict sub-dominance,and Euglenozoa and Cryptophyta show poor abundance at the littoral and semi-limnetic regions.The richness of phytoplankton and abundance of phytoplankton,Charophyta,Chlorophyta,Dinozoa,Chrysophyta and Cyanobacteria follow bimodal spatio-temporal variations.Closterium,Cosmarium,Staurastrum,Micrasterias,Netrium,Staurodesmus and Scenedesmus are notable genera,and 14 species collectively influence phytoplankton abundance.Phytoplankton registers high species diversity,lower dominance and high evenness.Amongst 15 abiotic factors,only the rainfall and sulphate exert notable influence individually,while the canonical correspondence analysis registers lower cumulative influence of the selected 10 factors on the littoral and semi-limnetic phytoplankton assemblages.This study merits interest for neglected biodiversity and ecology of small aquatic biotopes of India and urban wetlands in particular.

Rain Water Utilizing System Combing Artificial Wetland and Urban Drainage System

The method of utilizing rain water has been well developed in foreign countries to realize the sustainable development of water recourse while the method is still at the initial level in China. When considering the increasing of water shortage and urban flood, the awareness of utilizing rain water, as an inevitable trend, has been applied to various engineering technologies. This article has analyzed the principle of conventional road drainage system and the application of artificial wetland technology, also proposed to combine the road drainage system and artificial wetland, as a complex drainage system, to utilize the urban rain water, decrease urban flood pressure, and improve urban micro environment. The calculation principle and method for the complex drainage system are included as well.

The impacts of land-use and land-cover change on wetland ecosystem service values in peri-urban and urban area of Bahir Dar City, Upper Blue Nile Basin, Northwestern Ethiopia

Background:Even though wetlands are essential in enhancing water quality and providing recreation and entertainment opportunities in urban areas,their values are overlooked by the decision-makers.Underestimation of the economic value of wetland ecosystem services contributes to their continuing deterioration and inevitable loss.Investigating the changes in ecosystem service values(ESV)can provide crucial information for decision-making.This study,therefore,analyzes the temporal and spatial land-use/land-cover(LULC)change patterns over 35 years(1984–2019)intending to evaluate its impact on wetland ecosystem service values in Bahir Dar City,Ethiopia.Estimation and change analyses of ESVs were conducted by employing ArcGIS using LULC inputs of the year 1984,1994,2004,2014,and 2019 with their corresponding global value coefficients that were developed earlier and our own modified value coefficients for the studied landscape.Results:The results showed that wetlands and water bodies of the city and its peripheries had decreased by 75.71%(−1618 ha)within 35 years,while built-up area increased by 216.24%(+2599 ha).Cultivated land had increased slightly from 1984 to 1994 and then gradually declined since 1994.Changes in LULC had resulted in a decline of the total ESV.The total ESV had decreased from USD 29.73×10^(6) to USD 20.84×10^(6) in 35 years.This indicates the loss of nearly USD 8.9×10^(6) ESV from 1984 to 2019.A sensitivity analysis suggested the robustness of ESV estimation in the study area.All individual ecosystem services experienced a negative change.However,a greater reduction in ESV was observed for services such as water regulation,waste treatment,and habitats for maintaining biodiversity.The expansion of built-up area of Bahir Dar City was the major factor that contributed to the loss of ESV provided by wetlands.Conclusions:The loss of ESV resulting in LULC changes has a negative implication on local climate,waste management,and the livelihoods of the poor community.Thus,interventions should be made for the restoration and sustainable management of wetlands in the urban and peri-urban areas of Bahir Dar City.

A barrier to metal movement: Synchrotron study of iron plaque on roots of wetland plants

A wetland with attractive plants hosting birds and other wildlife is an esthetically pleasing prospect that is gaining popularity as a way of stabilizing or remediating metalcontaminated soils and sediment（Weber and Gagnon,2014;