Wetland Degradation Research Articles

Evaluating climate Change's impact on hydroelectricity in the Zambezi river basin

This study investigates the effects of climate change on energy security in Africa, specifically focusing on the Upper and Lower Zambezi Basin. Data from the Kariba River basin sub-catchments, annual reports, the Climate Data Store, and Teal Tool Earth's country-by-country climate data were analysed through quantitative and qualitative data analysis techniques. The Mann-Kendal Trend Analysis was used to analyse time series and test the significance of changes to the climate. The historical climate and hydrological data analysis showed evidence of a slight increase in average rainfall amounts in the Zambezi River Basin but with high rainfall variability in some areas. Despite droughts increasing in frequency, there is a general increase in hydrological annual average water flow in the Zambezi River at two of the three sample sites. The increased water flow through the region could be attributed to population growth-induced land clearance and the degradation of wetlands in Angola's highlands. Although there is an increase in hydrological water flow into Kariba, there are water shortages for hydroelectricity generation due to increased generation capacity, resulting in increased demand for more water than in previous years. The unsustainable water abstraction to meet growing energy demands contributes to low water levels in the lake. The study recommends energy diversification and new hydroelectricity where the potential exists in the basin to reduce over-reliance on Lake Kariba with care not to disrupt the basin's hydrology and other economic activities. The study results provide insight into the potential effects of climate change on energy security in Africa.

Assessing habitat quality at Poyang Lake based on InVEST and Geodetector modeling.

Poyang Lake is an essential natural wetland in the Yangtze River basin and plays a vital role in maintaining the ecosystem function and ecological security in the middle and lower reaches of the Yangtze River. However, the relative importance and spatial heterogeneity of the impacts of human activities and land use changes on ecological security needs to be further explored. Here, we analyzed the habitat quality level around Poyang Lake in 2022 and explored the factors of habitat quality change from a geographical perspective. The land use structure changes around the Poyang Lake basin from 2000 to 2022 were quantitatively analyzed, and then the relative importance and spatial heterogeneity of each factor on ecological security changes were investigated using geographic probes. The results show that (1) The worst quality habitat (0-0.1) consists mainly of construction land (1624.9 km2) with an area of 1634.64 km2; (2) Construction land continues to increase with the most significant change, and the dynamic land use attitude is 0.47. Grassland and mudflats have the greatest decrease. The increase in cultivated land in different periods is mainly due to the shift of water surface and forest land; (3) The drivers of habitat quality in Poyang Lake were significantly influenced by the interaction of socioeconomic factors. The explanatory power of population density interacting with the total year-end population and population density interacting with administrative area exceeded 0.84. These values were higher than the explanatory power of each individual factor, indicating that habitat quality was primarily associated with population density, total year-end population, and administrative area. These results suggest that human activities contribute to the degradation of wetlands around Poyang Lake. This study has significant reference value for coordinating human-land relationships in Poyang Lake, optimizing land management policy, and improving the sustainable development of cities.

Response of the Biological Components to Climate Change in the Wetland Ecosystem of the Qinghai-Tibet Plateau

Alpine wetlands play a role in water conservation, climate regulation, carbon sequestration, and biodiversity protection. However, due to the unique geological structure and climate characteristics of alpine areas, climate change is highly likely to have an impact on alpine wetlands and their ecosystems, including the abundance and distribution of local species. This paper focuses on analyzing the composition, quantity, and distribution changes of wetland organisms, including producers, consumers, and decomposers. The research findings indicate that, with the intensification of human activities and climate change such as global warming, despite the emergence of some new wetlands, many natural alpine wetlands on Qinghai-Tibet Plateau are facing shrinkage and are gradually retreating towards higher altitudes, latitudes, and wetter areas, which means the extinction of some plants and the shrinkage of wildlife habitats. Changes in wetland environment, such as drying, resulting from increased temperature and decreased precipitation, have led to a decline in biodiversity and degradation of alpine wetland ecosystems. Despite an overall increase in vegetation cover, wetland degradation has caused changes in plant species diversity and community composition. Climate warming have also affected wildlife migration and the activity of microorganisms. The changes in plateau wetlands are primarily shaped by climate conditions, while human activities act as accelerators, causing significant damage to wetland environments, leading to fragmentation and accelerated degradation. This paper proposes strengthening ecological monitoring and risk assessment in these regions, conducting further research, and promptly implementing necessary restoration measures to reduce the ecological risks caused by these changes.

WETLAND DEGRADATION AND LOSS DUE TO THE EXPANSION OF ANTHROPOGENIC ACTIVITIES

A wetland ecosystem covers about 5-10% of the earth's land. Wetlands play a significant role in the world's economy but they suffer from several threats from various influencing factors. Wetlands are destroyed due to the expansion of human activities and their effect on living and non-living organisms. Some of India’s and Gujarat's wetlands case studies highlight the worst conditions of wetlands from past decades. These case studies highlight the reasons for wetland degradation, and also which types of issues need to be addressed. Wetlands are the most important ecosystem on earth, and to control wetland degradation, it is essential to improve special laws and regulations and be aware of people to conserve ecosystems.

STATUS OF SELECTED WETLANDS IN AHMEDABAD

A wetland ecosystem covers about 5-10% of the earth's land. Wetlands play a significant role in the world’s economy but they suffer from several threats from various influencing factors. Wetlands are destroyed due to the expansion of human activities and their effect on living and non-living organisms. Studies highlight the reasons for wetland degradation, and also which types of issues need to be addressed. Wetlands are the most important ecosystem on earth, and to control wetland degradation, it is essential to improve special laws and regulations and be aware of people to conserve ecosystems. The present study reveals that the total water bodies are decreasing due to urbanization recorded in the Ahmedabad city of Gujarat state, India.

Attenuation of the contribution of groundwater to a wetland caused by groundwater overexploitation

AbstractThe continuous exploitation of groundwater has made wetland degradation an ecological and geological environmental problem that cannot be ignored and has had impacts on the ecological environment and human production and life. In this study, Modflow was used to simulate the wetland‐aquifer interaction during the multiyear pumping process, establish a quasi‐ideal model of wetlands based on the actual area of the Baiyangdian Basin, simulate the relationship of water quantity change between wetlands and piedmont plain aquifers during groundwater exploitation and its natural recovery process, and quantify the attenuation of the contribution of groundwater to wetlands caused by groundwater overexploitation. Two components of wetland water reduction are explored through the simulation and calculation of wetland‐aquifer interactions under different exploitation conditions. The results show that in the process of groundwater exploitation, the impact of groundwater overexploitation on wetland degradation is mainly divided into two parts: one is the reduced base flow from the piedmont plain to the wetland, and the other is the induced infiltration caused by the reverse recharge of groundwater from the wetland due to the pumping effect. Compared with the wetland water reduction during the pumping process, the process of water recovery during the natural recovery process is much slower, which indicates the residual effect of exploitation will continue for a long time. The findings provide a scientific reference for the management of water resources in wetland areas.

Stakeholders’ perceptions of wetland conservation and restoration in Wakiso District, Uganda

AbstractNatural wetlands are critically important to the lives and livelihoods of many people. Human activities result in the degradation of wetlands globally, and more so in developing countries prioritizing fast economic growth and development. With an increasing population in their immediate surroundings, wetlands in Wakiso District, Uganda, have become over-exploited to meet human needs. Policies, plans and projects have been put in place aiming at wetland conservation and restoration, but with limited stakeholder participation, have achieved limited success. Our research objective was to identify stakeholders, their perceptions, and understand the role these perceptions play in wetland conservation and restoration activities. To achieve these objectives, we used the ecosystem services concept within a qualitative, multi-site case study research approach. Findings show that stakeholders hold divergent perceptions on wetland ecosystem services, perceiving them as source of materials, fertile places for farming, cheap to buy and own, as well as being “God-given”. Furthermore, wetlands as habitats are perceived as not prioritized by central government. Implications for conservation and restoration vary with stakeholders advocating for (1) over-use, wise-use or not-use of wetlands and their resources, (2) educating and sensitization as well as (3) the implementation of the available laws and policies. This paper explores the findings and important implications for the conservation and restoration of wetlands in Wakiso District, Uganda.

Analysis of a 131-year longitudinal dataset of the Eurasian otter Lutra lutra in Hong Kong: implications for conservation

AbstractHong Kong is one of the busiest metropolises, and the Eurasian otter Lutra lutra is one of its most threatened species. We collected published data for 1890–2020 to document changes in local otter abundance and distribution over time. The 108 records revealed new distribution data and showed that decline began as early as the 1930s. The local Eurasian otter is strongly associated with coastal and alluvial wetlands, and its last refugium, the Yuen Long floodplain draining the Mai Po Inner Deep Bay Ramsar Site, has always been a critical habitat. Our analysis suggests that hunting is unlikely to be a major cause of the otter's decline. Rather, dependence on lowland wetlands makes it particularly susceptible to habitat loss caused by increasing urbanization. Auxiliary infrastructures and water pollution have also exacerbated wetland degradation to the detriment of otters and their prey. There is a need for greater cooperation amongst government agencies and landowners to guarantee otter survival: priority steps include the establishment of additional and interconnected wetland reserves, better stakeholder engagement and enforcement efficiency to tackle entrenched pollution problems, and flood prevention schemes that preserve or restore functional riverine ecosystems within critical otter habitats. The current otter distribution range has been earmarked for development in a government-led mega urbanization plan; the plight of the local Eurasian otter needs to be widely publicized to garner stakeholders' support and galvanize immediate conservation actions across society.

Forestry feedbacks in Malezales’ degradation: Insights from past to plan future policy-driven forestry expansion over wetlands in Argentina

The degradation of wetlands is a worrying phenomenon, given its ecosystemic importance due to the provision of environmental services. In Argentina, the process of wetland degradation is fast and almost unknown due to the lack of control and monitoring. Malezales grasslands are wetland ecosystems, indeed poorly studied and endemic of Argentina's northeast. This study aimed to understand the impacts of policy-driven forestry expansion in wetlands, searching for tools and patterns to plan sustainable afforestation. Geographic information systems and remote sensing-based models were used to produce and analyze historical data of the forestry expansion and malezales degradation on inceptsols located in northeastern Corrientes, Argentina. The results showed that the region experienced extensive forestry expansion over the last 20 years. Pinus spp. plantations expanded on the most degraded malezales, which suggests some sustainability in the expansion process. However, the remaining malezales present current worrying levels of degradation. The intensification of the degradation process is imminent because livestock pressure on malezales has been intensified after the loss of areas due to the forestry increasing. We present a preliminary zoning of areas for conservation or forestry expansion in malezales. We found that 40.2% (47571 ha) of the current area of malezales could be used for forestry expansion, while 59.81% (about 70793 ha, 41.56% of the original ecosystem) is of priority for conservation or protection actions. A complete zoning of malezales is recommended, and policies to foment the correct management of malezales and forestry should therefore be implemented.

Effects of Wetland Degradation on Community Livelihoods: A Case of Mabengere Wetland in Kisiita Sub County, Kakumiro District, Uganda

Wetlands in Uganda play vital ecological, economic, socio-cultural, scientific and recreational purposes and yet they are currently threatened by anthropogenic and bio geophysical factors. The current study was initiated to determine the drivers of wetland degradation; and to assess the benefits and costs as a result of wetland degradation, to members of the local community in Kakumiro district, Uganda. A cross sectional research design that involved the collection of both quantitative and qualitative data from three hundred and eighty-seven respondents was used. Data were collected using a questionnaire, Key informant interview guide from the key informants and observation check list. Key findings revealed that sand and clay mining, agricultural activities, gathering building materials were the key activities carried out, which significantly affected the wetlands at P<0.05. In addition, the activities carried out in the wetlands significantly improved the livelihoods of the people living around them at P<0.05. The water levels in the wetlands were reduced that led to shortage of portable water and the water for watering animals, and also led to outbreak of fires which contributed to a reduction in the wetland’s biodiversity. This was confirmed by the Chi-square test which revealed that degradation of wetlands contributed to the costs incurred by members of the local community at P<0.05. It was therefore recommended that alternative sources of energy and building materials be availed like planting of upland trees. Also, there should be awareness intensification to members of the local community about the values and uses of wetlands aimed at scaling down their degradation.

Evaluation of agricultural wetland utilization and landscape design

AbstractWater 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.

Рotential threats of Kakhovka catastrophe to bird populations of different ecological groups

Any military action involves a number of risks for the existence of animals. In the event of the destruction of hydraulic structures, not only aquatic ecosystems usually suffer, but also the ecosystems of islands and banks. Undermining the dam of the Kakhovska hydroelectric power station had a wide range of negative impact on the life of animals. A number of its consequences manifested themselves immediately after the destruction of the dam connected with drainage of bottom sediments in some regions and flooding of the coast in others. But one should also expect the transformation of faunal complexes associated with long-term changes in the water regime, and in some regions with drying and moisture deficiency. The purpose of this work is to assess the species composition of birds whose populations will suffer population losses as a result of the Kakhovka catastrophe in the short and long term on a regional and global scale. The published lists of bird species for the territories affected by the Kakhovka catastrophe an analysis was made: for the Kakhovka reservoir, the 'Kinburn Kosa Regional Landscape Park, the Black Sea Biosphere Reserve; and for the registration of some rare species in the region. Questionable data was checked against an electronic database https://uabirds.org/. We assessed the species composition of birds whose populations may decrease in number as a result of the Kakhovka catastrophe in the near and long term. Problems of regional and global scale are considered. The status of residence and ecology of birds were taken into account. Birds affected as a result of the Kakhovka catastrophe were divided into 3 groups: І — 82 species — birds nesting in the region of the disaster and lost part of their populations this year. These are birds that build nests in aquatic vegetation, not high in trees, shrubs, on the ground on the islands; ІІ — 69 species — birds that will lose their habitats in the coming nesting seasons due to changes in the Dnieper channel, water regime and the development of devastation processes. These are limnophilous that inhabited the thickets of the coastline and the islands of the Dnieper; ІІІ — 121 species — birds that will lose habitats for feeding and shelter during migration and wintering. The number of not only populations that nest in Ukraine will suffer, but also those migrating from Europe and Asia. And a group of birds (33 species) that are unlikely to be affected. The catastrophe of the undermining of the dam of the Kakhovska hydroelectric power station harms the biodiversity and integrity of habitats on a large area of the banks of the lower reaches of the Dnieper. The effects of the disaster on natural communities will have a lasting impact. We predict a change in the biotopes of the existence of birds in the direction of degradation of wetlands and drainage of terrestrial ones, which will lead to a change in the species composition of birds in the region. Relevant in the future will be the study of the succession processes of ecosystems on the banks of the lower reaches of the Dnieper and changes in the communities of birds that inhabit them. The consequences of the catastrophe we have an impact on migratory bird species on a global scale.

Seasonal Influence on the Microbiology and Physicochemistry of Crude Oil Polluted Wetlands

Pollutants such as crude oil spills in an environment, affect the physical, chemical and biological properties of that environment. This study was conducted to determine the effect of seasonal variations on the microbiological and physicochemical characteristics of three crude oil-polluted wetlands in Rivers State, Nigeria. Soil samples were collected at 3 depths (0-15cm, 15-30cm and 30-45cm) with the aid of a hand auger, sampling was done for a period of twelve months covering the rainy (March to August) and dry seasons (September to February). Samples were analyzed for physicochemical characteristics, using standard analytical and microbiological methods. The data obtained was analyzed using the statistical package for social science (SPSS) version 22 and Duncan’s multiple range test was used to separate means where differences occurred. Microbiological analyses showed that significantly higher microbial counts were observed in the dry season than in the rainy season in the wetland samples which could be due to favourable environmental conditions during the period of study. Wetland soil total heterotrophic bacterial (THB) count in the wet season ranged from 1.09x107cfu/g to 10.45x107cfu/g and from 2.43x107cfu/g to 18.56x107cfu/g in the dry season. Total heterotrophic bacteria had the highest population in all soil depths (0-15cm, 15-30cm and 30-45cm) in both seasons. Hydrocarbon-utilizing bacteria such as Bacillus subtilllis, B. rigui, B. flexus, Lysinibacillus macrolides, Staphylococcus aureus, Proteus penneri and fungi such as Aspergillus species, Fusarium species, Mucor species and Rhizopus species were genetically identified in this study. Temperature and other physicochemical parameters in the wetlands were altered due to the variation in season. Higher temperature ranges were observed in the dry season than in the rainy season as seen in Iwofe, temperature ranged from 26.500C (0-15cm) to 28.500C (30-45cm) in the rainy season while in the dry season it ranged from 31.500C (0-15cm) to 33.500C (30-45cm) which was above FEPA permissible limit of 300C for soil temperature. The study showed that season of study as well as crude oil spillage have significant effects on the microbiology and physicochemical characteristics of wetlands and therefore, contribute to microbiological degradation in wetlands.

Detecting Wetlands within the Gomoa East District of Ghana through the Lenses of Sentinel-1 SAR Data Using Google Earth Engine for Ecosystem Conservation and Water Resource Management

This study presents a comprehensive analysis of wetlands within The Gomoa East District of Ghana using the powerful synergy of Sentinel-1 Synthetic Aperture Radar (SAR) data and the Google Earth Engine platform. The primary objective was to assess the status of wetlands in the region and evaluate their implications for ecosystem conservation and water resource management. Through the integration of multi-temporal SAR data, the study identified wetland areas and changes in their spatial distribution over time. Notably, the results revealed a concerning degradation of wetlands, with a loss of 260040 square meters in wetland areas, underscoring the critical need for conservation efforts. The study showcases the potential of Sentinel-1 SAR data and Google Earth Engine as valuable tools for monitoring wetlands, emphasizing their pivotal role in environmental sustainability and community well-being. Conservation strategies are imperative to safeguard these vital ecosystems and ensure a sustainable future. This research contributes to the knowledge base for wetland preservation and supports informed decision-making for the environmental management and ecological health of Gomoa East District in Ghana.

Transformation of phosphorus forms and its regulation on phosphorus availability across differently degraded marsh soils

AbstractSoil phosphorus (P) is a vital nutrient that controls wetland productivity and ecological functions. However, the effects of soil P forms on P availability during wetland degradation are relatively unknown. We selected differently degraded marshes, including non‐degraded marsh (NDM), lightly degraded marsh (LDM), moderately degraded marsh (MDM), and heavily degraded marsh (HDM), to research the changes in soil P forms by sequential chemical extraction and its regulation on P availability in the Zoige Plateau, China. The results showed that compared with the 0–30 cm soil layers of NDM, the main changes in total P concentration were a significant increase of 31.6%–44.2% in LDM and MDM, and the available P concentration increased by 28.7%–76.2% in LDM and MDM but decreased by 4.0%–47.5% in HDM with a lower P activation coefficient. Marsh degradation increased the concentration of soil dicalcium phosphates, P occluded in iron hydroxides, and organic P from the entire profile by 46.7%–137.7%, 31.7%–49.3%, and 78.1%–82.1%, respectively, while it decreased that of iron oxide surface adsorbed P and apatite P by 17.2%–32.2% and 15.3%–27.8%, respectively. Soil available P was mainly related to organic P and P non‐occluded in iron oxide minerals, which might also be a non‐negligible direct source of available P. The transformation from apatite P to organic P was an important regulatory mechanism of P availability in soils during marsh degradation. This study revealed the transformation trajectory of soil P forms owing to soil desiccation accompanied by plant community changes and overgrazing during alpine marsh degradation, and the risk of P limitation in HDMs with low soil available P. For degraded marsh restoration, some measures for improving P availability should be implemented in the future, such as grazing exclusion and the application of organic fertilizer.

Remote sensing inversion of water quality parameters in the Yellow River Delta

In recent years, with the rapid socio-economic development of the Yellow River Delta (YRD), the pressure on the supply of water resources has continued to rise. The development of oil-based industries has also led to a series of ecological and environmental problems, such as wetland degradation and water quality deterioration. As an increasing number of rivers are getting polluted, resulting in the deterioration of their water quality, monitoring, managing, and protecting water resources in the YRD is particularly important. In this study, water quality monitoring data and simultaneous Sentinel-2 image data from April 30, 2020, to October 26, 2021, were used to construct an experimental sample in the YRD. Water quality parameters (WQPs) concentrations were correlated with Sentinel-2 image element spectral reflectance and sensitive bands were selected. An empirical method based on the characteristic bands was used to invert a total of six water quality indicators, namely dissolved oxygen (DO), permanganate index (CODMn), ammonia nitrogen (NH3-H), total phosphorus (TP), total nitrogen (TN) and turbidity. The results show: (1) A total of five water quality inversion models for DO, TN, CODMn, TP and TN were effective in the areas of the Guangli River, the Tiaohe and the Branch River. The inversion accuracies of the five inversion models (R2of 0.6099, 0.9271, 0.9581, 0.8784 and 0.7387; RMSE of 1.2723, 0.3413, 0.9923, 0.0118 and 1.8476; RPD of 1.53, 2.08, 3.56, 2.76 and 1.53) indicated the feasibility of the water quality inversion method based on Sentinel-2 data using statistical theory for monitoring water quality concentration in the YRD. (2) The spatial distribution of water quality in the YRD was generally characterized by high water quality in the upper reaches and low water quality in the middle and lower reaches (except for some seasonal variations). Among them, the water quality of the upper reaches of the Guangli River was poor, with opposite trends in DO and TN concentrations. In the Tiaohe, CODMn and TP concentrations were not strongly correlated. However, CODMn and TP concentrations were high in the middle reaches where water quality was the worst. The TN concentrations in the Branch River decreased between 2020 and 2021, but the water quality is still in Category V. Therefore, continued attention and appropriate water quality management measures in the YRD are required. Further, by measuring water quality indicators at monitoring stations, regression-fitting equations for WQPs were established to obtain complementary multi-platform observations. Thus, the water quality conditions in the YRD region can be evaluated more accurately and quickly. The research results not only provide an important reference basis for the identification and monitoring of pollution sources, prevention and treatment of water environment pollution in the YRD, but also provide water security for socio-economic and ecological environment security.

Carbon dynamics of the plant-soil system during vegetation succession in dune-meadow cascade ecosystems in Horqin Sandy Land, China

Understanding the relationship between the plant-soil carbon dynamics and environment is important for the management of arid and semi-arid ecosystems. Under long-term overgrazing and reclamation, the landscape of the Horqin Sandy Land has transformed into a dune-meadow ecotone. However, the effects of landscape evolution on the carbon dynamics in this region remain poorly investigated. This study evaluated changes in plant-soil organic carbon content and stable carbon isotope ratios (δ13C) attributable to vegetation restoration in dune ecosystems and wetland degradation in meadow ecosystems, and evaluate the indicative implications and driving mechanisms of the 13C enrichment in the plant-soil system. The dune ecosystems comprised semimobile dune with 25- and 15-year-old Artemisia Halodendron communities (SMAH1, SMAH2), fixed dune with 30- and 40-year-old Caragana microphylla communities (FCM1, FCM2), semimobile dune with 40-year-old Salix gordejevii community (SMSG), and transitional zone with a 30-year-old artificial Populus forest (TPF) in the gentle lower part. The meadow ecosystems comprised a corn field that transformed from natural meadow over 40 years (MCF) and a natural meadow with Phragmites australis community (MPA). The results show that plant leaves in different landscapes in the cascade ecosystems had various δ13C. And the mechanism of the leaves carbon isotope fractionation with increasing leaf age was significant and consistent, but different vegetation communities had different nutrient utilization strategies during ontogeny. Landscape types and soil depths are the key factors affecting SOC content, its δ13C (δ13Cs) and SOC stock changes. And the overall soil carbon turnover was accelerated with vegetation restoration. Especially in TPF, vegetation restoration is particularly significant for SOC, which is mainly reflected in the upper 20 cm of soil profile. The degradation of MPA to MCF led to loss of SOC content and storage and accelerated the soil carbon turnover rate. The δ13Cs of the dune and meadow ecosystems were positively correlated with organic-rich litter nitrogen content and were significantly negatively correlated with SOC, soil moisture, clay content, and total organic carbon to total nitrogen ratio of organic-rich litter. The revegetation using native and introduced tree and shrub species increased SOC content in dune ecosystems and significantly promoted the degree of its coupling with soil nitrogen and water.

Impact of Artisanal Gold Mining on Wetland Health in Buhweju District, Southwestern Uganda

Wetland degradation due to anthropogenic activities including artisanal gold mining is widely common in Uganda, and this affects vegetation health status if not controlled. However, the use of the Normalised Difference Vegetation Index (NDVI) to determine the health status of wetlands is rare. In this study, remote sensing techniques with the use of spatial-temporal Normalised Difference Vegetation Index (NDVI) were used for the wetlands in Bitsya Subcounty, Buhweju district (noted for artisanal gold mining with the use of mercury) to determine the wetland health status for the period between 2012-2021. This was for the purposes of identifying target areas for intervention and developing appropriate, location-specific intervention options. 7 images of 30 * 30 m and 3 images of 10 * 10 m respectively, ortho-rectified, cloud-free Landsat and Sentinel images obtained from the USGS archive were analysed. The results showed that the high NDVI value (0.775) was detected in the year 2019 and the low NDVI value (0.068) was detected in the year 2017. The NDVI maps showed low values mostly in the middle of the wetland where artisanal gold mining was mostly taking place, indicating a huge decline in the wetland health status as compared to other wetland edges noticed with high NDVI. The results from the study suggest that the wetland policies in the study area could not be effectively implemented and this reduces the vegetation health status, threatening the functionality of the wetland and as well as loss of the free natural goods and services derived from them. This necessitates the development of wetland restoration campaigns. However, failure to implement the wetland policies may have an ecosystem impact on the wetland micro and macro-organisms, soil nutrients, and water quality as well as a decline in vegetation health

Process analysis and mitigation strategies for wetland degradation caused by increasing agricultural water demand: an ecology–economy nexus perspective

BackgroundFarmland expansion has played a major role in wetland degradation in Heilongjiang Province, China in recent decades. Farmland expansion increases the demands for water, thereby affecting wetland water cycles, and promoting the shrinkage of wetland areas and degradation of ecosystem functions. As an open system, agricultural production is limited by both ecological and socioeconomic conditions. However, our understanding of wetland degradation caused by farmland expansion from the perspective of the ecology–economy nexus is limited.MethodsA correlation between farmland expansion and agricultural economic activities was established, and wetland degradation driven by agroeconomic activities was inversely derived using a multi-regional input–output (MRIO) analysis. We developed an ecology–economy nexus framework to explore the ecological process of the area and water demand tradeoffs between wetland degradation and farmland expansion, the economic process of wetland degradation driven by food consumption, and the nexus between the two processes. We finally explored strategies to mitigate wetland degradation due to increased agricultural water demand.ResultsFarmland expansion contributed to 93.76% of the total degraded wetland area. There was a significant negative correlation between wetland area and the water consumption for crop production, but no significant correlation between wetland area and the ecological footprint of croplands. The direct wetland degradation caused by local final demand accounted for 63.02%, while the indirect degradation caused by non-local final demand accounted for 36.98%. Hebei, Shandong, Liaoning, Inner Mongolia, and Shanghai were the top five provinces contributing to indirect wetland degradation in Heilongjiang. Our findings indicated that a mixed scenario combining water footprint reduction per unit yield with food export reduction could maximize wetland restoration while reducing local farmland–wetland competition for water.ConclusionsOur research highlights the effects of economic processes in the agricultural sector on wetland degradation, and showed that the adjustment of food trade patterns can effectively promote wetland restoration.

Socio-Economics Importance and Its Determinant Factors of Wetlands in Eastern Ethiopia

Wetland in Ethiopia provides various socio-economic benefits for the local community and for the people who live around the ecosystem. Despite this, the wetland in Ethiopia provides various benefits to the local community, it is under severe pressure and degradation from natural causes and human activity. The present study aims to assess the socio-economic importance of the wetland that existed in the East Harerghe zone. Both primary and secondary data were employed to answer the study objective. Accordingly, a total of 220 respondents were selected to administer the questionnaire. SPSS version 20 was used for data analysis and a multiple regression model was used to see the relationship between dependent and independent variables. The income generated varies in two lakes, Lake Langie is 56,196.8 birr, whereas the mean annual income in Lake Adele is 54,662.6 birr. The determining factor for the income generated from the wetland is the respondent land size and the distance between the wetland and farmland. Among respondents, 53.2% of the respondents perceived that the lakes are highly degraded followed by less degraded 33.9% and 12.6% in good condition. Agricultural expansions are indicated as the major triggering factor for the degradation of wetlands followed by population pressure, sedimentation, deforestation, overgrazing, and poor law enforcement and regulation respectively. Most respondents are interested in participating in conservation activity and the recommended activity to tackle this degradation is soil and water conservation and tree planting activity.