Wetland Utilization Research Articles

Characteristics of Changes in Typical Mountain Wetlands in the Middle and High Latitudes of China over the Past 30 Years

Analysis of the driving mechanisms of wetland change can help identify spatial differences in the mechanisms affecting various elements, enabling a more scientific approach to the conservation and utilization of wetlands. This study investigated the impacts of natural and anthropogenic factors on the spatiotemporal evolution of the Altay and Greater and Lesser Khingan Mountains areas using Landsat satellite image data from 1980 to 2018 and fieldwork data from 2019 to 2020. A transfer matrix, correlation analysis, and dynamic characteristics were applied to calculate and analyze the transformation types and areas of wetland resources across all consecutive periods. Finally, the dominant factors influencing the spatiotemporal evolution of the wetland were explored and revealed using the drought index (Standardized Precipitation Index, SPEI) and statistical almanacs. The results showed: (1) From 1980 to 2018, the wetlands area in the Altay Mountains exhibited a decreasing trend, whereas the wetlands area in the Greater and Lesser Khingan Mountains showed an increasing trend. The primary type of wetland transfer in the Altay Mountains was grassland, whereas in the Greater and Lesser Khingan Mountains regions, the primary types of wetland transfer were grassland and forestland. The wetlands area transferred out of the Altay Mountain region was larger than the area of wetland types transferred into during 2010–2018, whereas the wetland areas of the Greater and Lesser Khingan Mountain areas showed the opposite trend. (2) From 1980 to 2018, the wetland ecosystem types in the Altay Mountains exhibited the highest dynamic and conversion degrees of the channels. Similarly, the mountain areas of the Greater Khingan Mountains showed the highest dynamic and conversion degrees of marshes and channels among the wetland types. In addition, the mountainous areas of the Lesser Khingan Mountains showed the highest dynamic and conversion degrees for reservoirs and rivers. (3) Natural driving factor analysis revealed that the SPEI values in the Altay Mountains and the Greater and Lesser Khingan Mountains areas exhibited an increasing trend, indicating that the climate has been warm and humid over the past 30 years and that the expansion of cropland and human-made wetland areas has been significantly influenced by human activities. Therefore, the wetland areas of the Greater and Lesser Khingan Mountains in the northeast are strongly influenced by human activities, whereas the wetland in the Altay Mountains in the northwest is strongly influenced by the climate.

Remotely Sensed Changes in Qinghai–Tibet Plateau Wetland Ecosystems and Their Response to Drought

Wetland ecosystems in the Qinghai–Tibet Plateau are pivotal for global ecology and regional sustainability. This study investigates the dynamic changes in wetland ecosystems within the Chaidamu Basin and their response to drought, aiming to foster sustainable wetland utilization in the Qinghai–Tibet Plateau. Using Landsat TM/ETM/OLI data on the Google Earth Engine platform, we employed a random forest (RF) method for annual long-term land cover classification. Standardized precipitation evapotranspiration indices (SPEI3, SPEI6, SPEI9, and SPEI12) on different time scales were used to assess meteorological drought conditions. We employed a Pearson correlation analysis to examine the relationship between wetland changes and various SPEI scales. The BFASAT method was used to evaluate the impact of SPEI12 trends on the wetlands, while a cross-wavelet analysis explored teleconnections between SPEI12 and atmospheric circulation factors. Our conclusion is as follows: The wetlands, including lake, glacier, and marsh wetlands, exhibited a noticeable increasing trend. Wetland expansion occurred during specific periods (1990–1997, 1998–2007, and 2008–2020), featuring extensive conversions between wetlands and other types, notably the conversion from other types to wetlands. Spatially, lake and marsh wetlands predominated in the low-latitude basin, while glacier wetlands were situated at higher altitudes. There were significant negative correlations between the SPEI at various scales and the total wetland area and types. SPEI12 displayed a decreasing trend with non-stationarity and distinct breakpoints in 1996, 2002, and 2011, indicating heightened drought severity. Atmospheric circulation indices (ENSO, NAO, PDO, AO, and WP) exhibited varying degrees of resonance with SPEI12, with NAO, PDO, AO, and WP demonstrating longer resonance times and pronounced responses. These findings underscore the significance of comprehending wetland changes and drought dynamics for effective ecological management in the Chaidamu Basin of the Qinghai–Tibet Plateau.

The Sustained Response of Dissolved Inorganic Carbon to Urban Constructed Wetland in the Fenhe River, China: A Case Study

Sustained wetland utilization has been effective in purifying urban riverine pollutants and promoting sustainable development. However, its effect on water CO2 system remains unclear in semi-arid areas. In this study, seasonal monitoring of the carbonate system was performed at two compared stations, i.e., in constructed wetland (Xiangyun station) and its upstream (Lancun station) in a semi-arid river (the Fenhe River) in China. As indicated by the result of the sustained monthly observation from May 2020 to May 2021, riverine dissolved inorganic carbon (DIC) and partial pressure of CO2 (pCO2) reached 30.9–46.7 mg L−1 and 524–1050 μatm in Lancun station, respectively, whereas the above-described values declined significantly in Xiangyun station with the values of 24.1–39.1 mg L−1 for DIC and 188–873 μatm for pCO2. Compared with the Lancun station where the carbonate system was primarily controlled by natural factors (e.g., carbonate weathering and temperature), significant aquatic photosynthesis and calcification precipitation due to constructed wetland triggered the decrease in DIC and pCO2 and dominated their temporal variation in Xiangyun station. Thus, the large CO2 reduction arising from constructed wetlands may create vital paths for CO2 neutralization and sustainable conservation in urban rivers in arid and semi-arid areas in the future.

The Value of Surface Freshwater Supply Services in the Wetlands of Jilin Province, China

Wetlands are ecologically and socioeconomically crucial areas. The application of economic valuation methods could ensure the sustainable utilization of wetlands. Utilizing wetland survey data from Jilin Province, China, representative of the years 2013 and 2017, we assessed the market value of water obtained from wetlands. Simultaneously, we employed the PLUS model to predict changes in wetland areas of different types over the next decade and analyzed their impact on the value of freshwater resource supplies. The results indicate the following points: (1) the area of wetlands decreased from 10,852.84 km2 in 2013 to 10,794.46 km2 in 2017 and that, in 2027, this was projected to further decrease to 10,614.37 km2, with river wetlands experiencing the most substantial decline; (2) the freshwater volumes in 2013 and 2017 were 20.81 × 108 and 20.09 × 108 m3, respectively, representing a 3.58% decrease. The volume for 2027 was projected to further reduce to 19.74 × 108 m3, with lake wetlands contributing the most to water resources and marsh wetlands contributing the least; and (3) the obtained total value of freshwater continuously increased, rising from CNY 8.384 billion in 2013 to CNY 8.642 billion in 2017, and this was projected to further increase to CNY 9.101 billion in 2027. There was regional variation in the value of wetland freshwater resource supplies, with differences in the per unit area and per capita value among administrative units. These findings can facilitate the optimal allocation of freshwater resources in Jilin Province, promoting its sustainable development while ensuring wetland conservation.

The influence of management practices on plant diversity: a comparative study of three urban wetlands in an expanding city in eastern China.

Rapid urbanization has drawn some aquatic environments into the urban texture from the outskirts of cities, and the composition and distribution of plant species in urban wetlands along the urban gradient have changed. Understanding the drivers of these changes will help in the conservation and utilization of urban wetlands. This study investigated the differences in plant diversity and associated influencing factors in three wetlands, Xixi wetland, Tongjian Lake wetland, and Qingshan Lake wetland, which are located in a core area, fringe area, and suburban area of Hangzhou City, respectively. The results showed that a total of 104 families, 254 genera, and 336 species of plants were recorded in the Xixi wetland; 179 species, 150 genera, and 74 families were found in the Qingshan Lake wetland; and 112 species, 96 genera, and 57 families were collected in the Tongjian Lake wetland. The main plant species and flora distribution of the three urban wetlands showed similarities. Indigenous spontaneous vegetation was highest in the Xixi wetland, while cultivated plant species were most abundant in the Tongjian Lake wetland. The introduction of cultivated plants decreased the distance attenuation effect of plant communities, which led to a certain degree of plant diversity convergence among the three wetlands. Eight endangered plants were preserved in the Xixi wetland by planting them in suitable habitats. Ellenberg's indicator values showed that the proportion of heliophilous plants was higher in the Qingshan Lake wetland, while the proportion of thermophilous plants and nitrogen-loving plants in the Tongjian Lake wetland was higher than in the other two wetlands. The importance of artificial interference factors affecting the differences in plant diversity was significantly higher than that of natural environmental factors in urban wetlands. The preservation of spontaneous plants and the introduction of cultivated plants had an importance of 25.73% and 25.38%, respectively. These were the main factors influencing the plant diversity of urban wetlands. The management mode that did not interfere with spontaneous vegetation and confined maintenance to cultivated plants in the Xixi wetland was beneficial for improving wetland plant diversity. Scientific plant reintroduction can also improve wetland plant diversity.

Study The Effectiveness of Reservoir Utilization In The Fishpond Water Management System In Maintaining Salinity For Fishpond Cultivation

The growing global population has led to an increased demand for food to meet humanity’s needs. However, the degradation of productive land presents a significant challenge regarding ensuring food availability. The utilization of wetlands has emerged as a feasible alternative. As the second-longest coastline in the world, Indonesia holds great potential for wetland development, for instance, fishpond. Nevertheless, the prevailing extensive traditional fishponds have low productivity and fail to maximize profits. Therefore, shifting towards more intensive cultivation methods is necessary to enhance productivity and increase profitability. This study aims to evaluate the effectiveness of reservoirs in maintaining salinity levels, aiming for technological improvement in semi-intensive fishponds. A water system model in the pond irrigation area is utilized to accomplish this. The model consists of two variations: Model 1, which includes rivers and channels, and Model 2, which combines rivers, channels, and reservoirs. The study results indicate that integrating reservoirs into the water system can significantly enhance salinity distribution. Model 2, which combines the reservoir component, demonstrates superior salinity dispersion. Furthermore, this enhanced dispersion persists over a longer period. These findings underscore the potential of reservoir utilization to improve the effectiveness of semi-intensive fishponds and their overall productivity.

HLEL: A wetland classification algorithm with self-learning capability, taking the Sanjiang Nature Reserve I as an example

Wetland ecosystems have been severely damaged by atmospheric pollution and other environmental problems for decades. Reasonable protection, restoration, and utilization of wetlands have become priorities for environmental protection. Obtaining high-precision wetland map products is essential for ecological research as well as formulation and implementation of conservation policies. This study proposes a hierarchical labeling ensemble learning (HLEL) algorithm with self-learning capabilities to achieve high-precision wetland land cover and land use (LULC) classification by adapting self-learning hierarchical results. This study evaluated the classification performance of HLEL, random forest (RF), support vector machine (SVM), artificial neural network (ANN), and Gaussian Naive Bayes' (GNB) with GF-6 WFV multispectral images as the database and Sanjiang National Nature Reserve I in China as the study area. The results showed that the HLEL algorithm has an advantage over a single algorithm when using the feature set filtered by ReliefF, even if the complete feature set is used without feature selection. The overall accuracy of the classification results is improved by 0.4%, 5.8%, 1.3%, and 9.0% when compared to the four single algorithms RF, SVM, ANN, and GNB, respectively. In robustness tests, HLEL consistently outperformed the other algorithms for different training sample set sizes, with overall accuracy improvements of 0.4–6.9%, 5.8–11.5%, 1.3–4.4%, and 9.0–14.0% compared with RF, SVM, ANN, and GNB, respectively. The overall accuracy standard deviation of HLEL is 1.22%, proving that HLEL has low sensitivity to the size of the training data. The HLEL algorithm demonstrates exceptional precision when applied to diverse datasets. The overall accuracy of HLEL in Sentinel 2, Landsat 8, and GF-6 WFV increased by 3.1% to 22.7%, 3.1% to 39.0%, and 0.4% to 9.0%, respectively, when compared to the overallaccuracy of the basicclassifiers. The results demonstrate the feasibility of HLEL, an algorithm with high accuracy and data robustness, in applying wetland LULC classification and providing a new solution for wetland cover mapping.

From separation to incorporation: Development of a unifying framework that integrated bird habitats with public recreation spaces within the wetland park system

The Ramsar Convention places central emphasis on the protection, restoration, and utilization of wetlands. Wetland species and their habitat protection is an important embodiment of wetland system protection. Simultaneously, the importance of recreation as a form of human activity within wetlands should not be underestimated. Wetland parks, as a mode of rational wetland use, provide the public opportunities for leisure and entertainment, exemplifying China's commitment to the Ramsar Convention on Wetlands. However, With the acceleration of urbanization, the degree of fragmentation of the wetland system is increasing. The wetland park and its surrounding landscape elements are separated from each other, resulting in the phenomenon of islanding, which is not conducive to the protection and utilization of wetland biodiversity. This study focuses on Yancheng coastal wetland, a UNESCO World Heritage site in Jiangsu, China, as its research area. It integrates habitat birds, a core component of wetland biodiversity, into the development framework of wetland parks. The study proposes the use of composite habitat corridors to connect fragmented bird habitats with public recreational areas, establishing a collaborative wetland park system. The methodology involved three key steps: (1)Spatial Modeling. Utilizing Maxent, the spatial distribution of birds and public recreation areas was modeled, and suitable patches for both were extracted. (2) Corridor Identification. Linkage Mapper was employed to identify bird and recreational corridors, while the MCR model was used to pinpoint composite habitat corridors. (3) Network Development. Corridors generated in the previous step were superimposed on the ArcGIS platform to create a network of interconnected bird habitats and public recreation areas within the wetland park system. The study's results demonstrate: (1) There are obvious spatial distribution differences between the current core bird habitat and public recreation areas in Yancheng coastal wetland. (2) The establishment of a composite corridor network realizes the interconnection between bird habitats and public recreation areas，among them, the corridor network in the southern region is short and dense, with higher stability. (3) The areas passed by the composite corridor network are mainly productive landscapes such as cultivated land and aquaculture ponds, and therefore, certain protection and restoration measures should be taken to create suitable habitat conditions for birds and humans. This study provides a novel model for wetland protection and sustainable utilization, particularly relevant to many developing countries facing similar challenges.

Mapping Coastal Wetlands and Their Dynamics in the Yellow River Delta over Last Three Decades: Based on a Spectral Endmember Space

The accurate mapping and analysis of coastal wetlands and their dynamics are crucial for local coastal wetland protection, sustainable social development, and biodiversity preservation. However, detailed mapping and comprehensive analysis of coastal wetlands remain scarce. In this study, we utilized Landsat-TM/OLI remote sensing data and employed the linear spectral mixture analysis (LSMA) method to map changes in coastal wetlands and analyze their dynamics in the Yellow River Delta (YRD) from 1991 to 2020. Our mapping results demonstrate high accuracy and are consistent with previous studies, boasting an overall accuracy exceeding 96%. During the period of 1991–2020, the YRD estuary expanded by approximately 8744.58 ha towards the east and north. The vegetation of P. australis and S. salsa underwent transformation due to agricultural practices or degradation to bare flats. Moreover, these areas saw extensive colonization by the invasive species S. alterniflora. Over the three decades, S. alterniflora expanded approximately 5 km along the coast, significantly impacting the local coastal wetland biodiversity. Furthermore, a considerable number of natural wetlands transitioned into human-made wetlands from 1991 to 2014. In particular, bare flats underwent substantial changes, transforming into aquaculture sites and salt exploitation areas. These dynamics in coastal wetlands had significant repercussions on local ecosystems, including wetland fragmentation, biodiversity depletion, and water pollution. However, post-2014, numerous wetland protection strategies were implemented, resulting in the restoration of natural wetlands. Detailed wetland mapping and dynamic analysis furnish valuable insights for the management, protection, and sustainable utilization of diverse coastal wetlands.

Evaluation of agricultural wetland utilization and landscape design

Abstract Water is an important component of agricultural wetlands, and human activities have disrupted the water cycle and its related functions, leading to problems such as water scarcity, water pollution, and wetland degradation. As an important water source conservation area and ecosystem, agricultural wetlands not only help maintain the sustainable use of water resources but also help improve the efficiency and quality of agricultural production. This article first introduces the water-centered utilization of agricultural wetlands, and then proposes the challenges and problems faced by agricultural wetland water resources management, focusing on the utilization and protection of water resources. Through research and analysis, the utilization efficiency of Xixi Wetland water resources was analyzed, and the importance of water resource protection and landscape design was analyzed using the Hangzhou Xixi Wetland as an example. This article proposed corresponding landscape design strategies for different utilization methods and analyzed the water resource utilization efficiency of the Xixi Wetland in the past decade through research. Under scientific management, the water resource utilization efficiency increased by 21% compared to 10 years ago. This article focused on ‘water’ and explored the utilization and landscape design of agricultural wetlands.

Sawah Surjan Environmental Management for Food Crop Diversification in Kulon Progo of Yogyakarta, Indonesia

The utilization of wetlands as agricultural land requires specific processing techniques, which are relatively expensive and unaffordable for local farmers. The optimization of wetlands as agricultural land by local farmers is usually made by elevating a certain part using the adjacent soil material known as Surjan system. The land management using Surjan system increases the diversity of agricultural products and deals with inundation problems. However, its environmental impact has not been widely studied.
 The research was conducted by observing the land with Surjan system in Kulonprogo area to determine its characteristics. Interviews with farmers were conducted to determine land management techniques. Soil and gas emissions samples were taken based on the age of the crop. The characteristics of land with Surjan system and conventional rice field were then compared to determine the difference, and the implications of the two agricultural lands on the environment are discussed.
 Surjan system can increase land productivity, and it can be adopted easily by farmers in other areas with inundation problems. This system is a planting system consisting of mound (the raised beds) and tabukan (the sunken beds that remain inundated). The mound part can be planted with secondary crops, horticulture, and other dryland crops, while the tabukan part can be planted with rice and used for mina padi (rice-fish) farming system. Surjan system provides benefits for environmental management through the prevention of floods and eutrophication, as well as reduction of greenhouse gas emissions in the atmosphere. Land management through Surjan system affects soil pH, redox potential, and organic matter. Land with Surjan system produces lower methane gas emissions than conventional rice fields. It produces methane gas of 4.06 - 45.73 µg / m2 / minute, with soil pH, redox potential, and organic matter of 6.65 - 7.69, (-) 49 - 10 mV, and 1.28 - 3.59%, respectively

Potentials of Constructed Wetland for the Treatment of Wastewater from Cocopeat Production Industry

The cocopeat production industry generates a significant amount of wastewater containing high organic loads and chemical residues, posing environmental challenges and economic concerns. This study aims to assess the potential of constructed wetlands as an innovative and sustainable approach for managing coco peat production industry wastewater. An artificial wetland was created and filled with 30% soil, 40% sand, 10% bio and hydrochar, and 20% gravel along with Canna indica was used as the plant component. Three types of hydraulic loading rates were studied: 5 ml/min, 10 ml/min, and 15 ml/min, with a retention time of 7 days.
 The results showed that the wastewater contains significant levels of Electrical Conductivity (5.24 – 6.31 dS m-1), Total Dissolved Solids (4190 - 5150 mg/L), Biochemical Oxygen Demand (730 - 818 mg/L), and Chemical Oxygen Demand (1825 – 2045 mg/L). The utilization of artificial wetlands along with Canna indica decreased the pollution loads by 42% of Electrical Conductivity, 41% of Biochemical Oxygen Demand, and Chemical Oxygen Demand, 45% of Total Suspended Solids, and 55% of Total Dissolved Solids.
 Based on the above results, constructed wetlands are recognized as a reliable wastewater treatment technique and a good solution for the treatment of coirpith washwater, which is a step towards a greener and more sustainable future. By integrating these natural filtration systems into the wastewater treatment process, industries can foster a harmonious coexistence with the environment, ensuring a balance between economic growth and environmental well-being.

Agricultural wetland utilization based on land cover restoration and water–ecosystem nexus

Abstract Wetlands, as a special ecological environment, are not only important biodiversity conservation areas but also one of the important agricultural resources. Agriculture plays an irreplaceable role in human society. It is directly related to human survival and development, and is also a part of people's environmental awareness and cultural inheritance. Based on the principles of sustainable development and strengthening environmental protection, people should pay more attention to the development and improvement of agriculture. However, with the advancement of urbanization, the area of wetlands continues to decrease, causing damage to ecosystems and posing a threat to some agricultural production. This article combined the transfer matrix of agricultural wetland utilization, landscape change rate, and landscape pattern index, used RS (Remote Sensing) and GIS (Geographic Information System) technologies to analyze the dynamic changes in agricultural wetland utilization and landscape of Honghu Lake in the Four Lakes region, and explored its changing factors. The results indicated that the construction land area showed an increasing trend in 2016, 2019, and 2022, while the wetland area of rice fields showed a first decreasing and then increasing trend.

Evaluation of urban wetland landscapes based on a comprehensive model — a comparative study of three urban wetlands in Hangzhou, China

Urban wetlands constitute an integral part of urban ecosystems. Unsurprisingly, wetland landscapes affect the frequency with which urban residents visit wetland areas. Objectively evaluating the beauty of landscapes and exploring the factors that influence their perceived beauty can inform urban wetland landscape design. This study selects three wetlands located in the core, fringe, and suburban areas of Hangzhou, respectively: Xixi wetland, Tongjian Lake wetland, and Qingshan Lake wetland. To explore the impact of ecological design techniques on the scenic beauty of wetlands, the selected wetlands were used to conduct field investigations. In addition, the wetland landscapes were submitted to public evaluations using scenic beauty estimation (SBE). At the same time, the factors affecting the beauty of the wetland landscape were quantified using the semantic differential (SD) method, and the impact paths of ecological design and plant diversity on scenic beauty were analyzed through the structural equation model (SEM). The results indicated that plant richness, cultural expression, color harmony, and coordination of landscape elements have both a significant and positive impact on the scenic beauty of urban wetlands. By way of contrast, habitat diversity had a significant yet negative impact. Across the three urban wetlands, ecological design techniques were found to significantly improve plant diversity and scenic beauty. This study demonstrated that the application of well-thought-out ecological design methods was conducive to the integration of environmental protection, landscape aesthetics, and the sustainable utilization of urban wetlands in the rapid urbanization process, providing a reference for urban wetland landscape conservation, planning, and design.

Morphological Characteristics and Hydrological Connectivity Evaluation of Tidal Creeks in Coastal Wetlands

Tidal creeks play a critical role in delivering water, suspended sediments, and nutrients to coastal wetlands, so it is important to understand the characteristics of the tidal creek system to guide the development and sustainable utilization of coastal wetlands. Using the coastal wetlands of the Liao River Estuary (LRE) as a study area, this study accurately divided the tidal flat based on the principle of tidal correction, extracted the linear features of tidal creeks using high-resolution remote sensing (RS) data, and then classified the tidal creeks on a tidal flat using the tidal creek ordering algorithm. Our study aimed to quantify the morphological characteristics of tidal creeks and qualitatively evaluate the parameters of the tidal creek network in the study area. The study results show obvious spatial heterogeneity in the order and the average length of tidal creeks in the coastal wetlands of the LRE. With the increase in the order of tidal creeks, the average length of tidal creeks increased exponentially and the number of tidal creeks decreased exponentially in the study area. The total density of tidal creeks was related to the beach surface elevation gradient, and the density and frequency of tidal creeks reduced substantially with an increase in the order of tidal creeks. The sinuosity ratio of tidal creeks declined sharply with a fall in the beach surface elevation gradient. The average bifurcation ratio of tidal creeks in the upper intertidal zone was higher than that in other zones, indicating that the tidal creeks in the upper intertidal zone were erratic. In addition, the hydrological connectivity of the tidal creek network in the upper intertidal zone and the development of the tidal creek system in the supratidal zone were the highest in the LRE. The study results help understand the spatial variations in tidal creek morphology under the influence of tidal hydrodynamics.

Exploring Spatial Relationship between Restoration Suitability and Rivers for Sustainable Wetland Utilization.

Wetlands are important ecosystems for biodiversity preservation and environmental regulation. However, the integrity of wetland ecosystems has been seriously compromised and damaged due to the reckless and indiscriminate exploitation of wetland resources during economic development by human society. Hence, wetland restoration has now attracted wide attention. Understanding wetland restoration suitability and its relationship with river grade and river distance is an important step in further implementing wetland restoration and ensuring an orderly wetland development and utilization. In this study, wetland restoration suitability is evaluated combining natural and human factors. Taking its result as an important basis, the spatial distribution characteristics of different levels of wetland restoration suitability are discussed for the studied region; the percentage distribution of different levels of wetland restoration suitability is analyzed for 10 km long buffer zones of rivers of different grades, and the association between the distribution of different levels of wetland restoration suitability and the river distance (2, 4, 6, 8, and 10 km) is also analyzed for different buffer zones of rivers in different grades. Our findings show that the spatial distribution of wetland restoration suitability is closely associated with the grade of rivers and the distance of the wetland patches from the river. The higher the river grade, the higher the percentage of the wetland with high restoration suitability within the same river distance. The percentage of wetlands with high restoration suitability has shown a notably decreasing trend as the river distance increases for the areas beside rivers of all grades, while the percentage of a wetland area with relatively high restoration suitability tends to increase as the river distance increases for the areas beside rivers of grade I and II and does not have a noticeable trend to change as the river distance changes for the area beside rivers of other grades. Results of this can provide technical support for wetland restoration suitability evaluation for plain areas, a spatial reference for wetland restoration prioritizing, and an orderly wetland development and utilization in future studies and planning.

Current situation and protection countermeasures of wetland resources in Shaanxi

In order to guide the management, protection and utilization of wetlands in Shaanxi Province, this paper analyzes and summarizes the current situation and existing problems of the protection and utilization of wetland resources in Shaanxi Province, and puts forward suggestions accordingly. There are 4 wetlands and 12 wetland types in Shaanxi Province, 308,500 hectares. The area and proportion of various wetlands are 257,600 hectares of river wetlands, 83.50%; 32,300 hectares of artificial wetlands, 10.46%; 7,600 hectares of lake wetlands, 2.46%; and 11,000 hectares of swamp wetlands, 3.58%. There are 77 families, 207 genera, 341 species and 3 varieties of wild vascular plants in the wetland, including 2 species of key wild protected species at the national level and 4 species at the provincial level. In view of the problems in the protection and utilization, such as the collaborative mechanism has not been established, the resource background has not been completely clear, and the investment is insufficient, we should build a scientific and appropriate wetland evaluation index system in Shaanxi Province, carry out the investigation and evaluation of wetland resources in the province, continue to carry out wetland ecological restoration and reconstruction projects, establish and improve wetland protection management and technical system, and formulate the protection and utilization direction of different types of wetlands.

Evaluating the contribution of wetlands to food security and livelihoods improvement in the Savelugu Municipality, Ghana

The study was conducted on three wetlands and four fringe communities in the Savelugu Municipality in Ghana’s Northern Region. The study evaluated the importance of wetlands to food security and livelihoods in the Savelugu Municipality using primary and secondary data sources. The contingent valuation method was used to determine respondents’ value of wetlands, whereas Kendall’s Coefficient was used to identify the factors influencing the reliance or utilisation of wetlands. The study results showed that wetlands were critical resources in study communities and contributed to people's livelihoods and food security and determined the kinds of livelihoods that existed in these communities. Out of the 79% of respondents (that is, 237 out of 300 respondents) who considered their households to be food secured, 73% of them attributed their food secured households to their reliance and use of wetland resources. Fertile soil for agriculture and tree nursery development, fish for consumption and income generation from the sales of wetland related products were the key contributions of wetlands to respondents’ food security. Furthermore, the study established that despite the potential contributions of these ecosystems to the people’s overall development, the wetlands are yet to be accorded the needed recognition as valuable resources by policymakers at the community and district levels. The disregard of wetland ecosystems by authorities, and as a consequence, the lack of attention/clear-cut regulations on their use, lead to overexploitation and degradation. It was observed in Bunglung and Nabogu wetlands that siltation is adversely affecting the capacity of the wetlands to provide their functions and services. The situation requires the attention of the Savelugu Municipal Assembly to dredge the silted wetlands. Key among the factors influencing wetland dependence and utilisation were climate change, soil fertility of wetlands and household income levels. Inhabitants’ activities such as obsolete fishing tools and farming practices, channelisation and indiscriminate waste disposal were identified to be detrimental to the wetlands’ sustainability.

Feasibility Analysis of the Utilization of Constructed Wetlands in Small High-Andean Urban Agglomerations

This article shows the results of bibliographic and documentary research and an in-situ visit to the treatment plants of small populations around the circunlacustrine ring of Lake Titicaca; with the aim of carrying out a feasibility analysis of the utilization and exploitation of artificial wetlands (wetlands) as an alternative for the domestic wastewater treatment of small urban agglomerations in high-Andean areas. From the visit to the thirteen localities and fourteen treatment plants, it was observed that in six of them, they just have stabilization ponds, and without maintenance, and eight have biological filter treatments and from these, just three have some maintenance, that is why the great majority is practically abandoned. In addition, they do not have an energy supply and they have sloping orographic conditions, as far as there is a great potential of eleven treatment plants, for the extensive technologies implementation (artificial wetlands), thereby reducing the discharge of wastewater without any treatment to the Lake Titicaca.

Socio-economic determinants of land use and land cover change in South-Kivu wetlands, eastern D.R. Congo: Case study of Hogola and Chisheke wetlands

In the South-Kivu province, wetlands are mainly converted into farmlands to ensure food and income security among rural populations. This study aimed at assessing the land use and land cover (LULC) change for the last three decades (1990–2020) in South-Kivu wetlands; mainly the Hogola and Chisheke, in Walungu territory, eastern Democratic Republic of Congo (DRC). Socio-economic determinants of LULC in the two wetlands were also assessed. Google earth (CNI/airbus) and airborne images were used for LULC while socio-economic data were collected through a survey questionnaire from 369 households. The Chi-squared Automatic Interaction Detector (CHAID) model allowed assessing factors determining conversion of wetlands' use. For the last three decades, there were 30 and 40% decreases in the acreage covered by Hogola and Chisheke wetlands, respectively, as a result of rapid farmland expansion and brick making. Farmers perceived wetlands as wastelands and thus unfit for agriculture and brick making activities. These two human activities provided significant monetary benefits to wetland users though the profitability of agriculture was dependent on practiced crops. The conversion of wetlands into farmlands was driven by annual household income, wetland utilization patterns, households' main activity and the seniority in exploiting wetlands. The perception of wetlands as degraded and wastelands, the exploited acreage and the farmer gender had also influenced significantly wetland conversions. On the other hand, perceiving wetlands as wastelands depended on the age of the household head, the inclination to brick making activities, the household's main activity and crop, and the wetland traditional/cultural values in the South-Kivu province. Though generating significantly higher annual incomes than any other land use in target wetlands, the conversion of wetlands for agriculture and brick making, under the current practices, is unsuitable for their sustainable management (use), as recommended to achieve the RAMSAR objectives of “wise use” of wetlands.