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A high-resolution Google-Satellite image showing part of the Bahir Dar City, where infrastructure development, residential and hotel construction are devastating lacustrine wetlands (Source: SASPlanet in 2020)
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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...
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Context 1
... the largest transition was observed from cultivated land to built-up area, from wetland to built-up area, cultivated land and grazing land, and from grazing land to built-up area and cultivated lands. This implied that built-up area and cultivated land expansion have been the major threats to the deterioration of wetlands in the Bahir Dar area (Figs. 3, 4 and ...
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Citations
... Moreover, specific actions have been developed to mitigate anthropogenic disturbances affecting wetland areas such as illegal land use, urbanization, trampling, burying ponds, water stress, alien species. These efforts aim to facilitate natural ecological successions (Manzano et al. 2019;Assefa et al. 2021). ...
Land-cover change dynamics were investigated in a Mediterranean coastal wetland to evaluate the long-term effectiveness of nature reserve management. A multitemporal analysis of land cover maps was conducted, utilizing visual interpretation of aerial orthophotos from the summer seasons of 1996, 2008, 2015, and 2021. Landscape changes were evaluated by transition matrices and chord diagrams. Maps were classified in accordance with CORINE land cover types at a fourth level of detail. The multitem-poral analyses provided a comprehensive overview of landscape changes within the reserve over the past 25 years. The most notable changes were the increase of wetland areas and the reduction of agricultural and artificial areas. Moreover, seminatural vegetation constantly extended over time. These changes reflected the continuous management activities within the nature reserve, encompassing agreements for water supply, restoration projects, and measures to counteract illegality. These operational actions induced fine-grained ecological changes (outcomes at ecosystem level). This study highlighted the importance of remote sensing and landscape analysis, matched with fine-grained management data, as tool for long-term monitoring. Such an approach provides valuable support in evaluating the effectiveness of strategies promoted in nature reserves hosting wet coastal ecosystems of high conservation concern.
... Studies have shown that LULC change has been intense in the highlands of Ethiopia. In particular, the expansion of intensive agriculture, urbanization, and extraction of forest products are accelerating over time to meet the requirements of an increasing population (Assefa et al., 2021). However, some studies have reported different trends of LULC changes. ...
The land use and land cover (LULC) change has far-reaching repercussions on both natural ecosystems and socioeconomic systems worldwide. The objective of this study is to investigate the dynamics of LULC, identify its causes, and evaluate its magnitude over three distinct time intervals (1993–2003, 2003–2013, and 2013–2023) in the Borkena watershed. Various methodologies, including remote sensing techniques, field observations, and focus group discussions, were employed to analyze the changes in LULC. Additionally, community perceptions were assessed through Focus Group Discussions (FGDs) and Key Informants Interviews (KIIs). Four LULC classification maps were generated and utilized to analyze land use changes, while image classification was conducted using the maximum likelihood method. The six primary land use and land cover categories considered were forest, cultivated land, shrubland, water bodies, built-up areas, and bare land. The results indicated an increase in settlements (77%), cultivated land (12%), and bare land (7%) between 1993 and 2023, while a decrease in forest cover (10%), shrubland (150%), and water bodies (−101%). These changes were predominantly observed in areas with gentle slopes (0–8%) and low altitudes (0–500 m). The findings suggest a significant expansion of agricultural and urbanization activities within the watershed. Anthropogenic activities such as agriculture and settlement had a more pronounced impact on low-lying and gently sloping areas compared to high-altitude and steep slope regions. Key informants and focus group discussions highlighted rapid population growth, rainfall variability, soil fertility decline, and a scarcity of fuelwood as the primary factors contributing to these changes.
... Wang et al., 2018;Zhang et al., 2020), we argue that this flood generation represents a wetland disservice. We thus are in the minority of studies acknowledging the flood potential of wetlands in cities (Assefa et al., 2021;Lundin, 1994) or urban wetland disservices in general. Additionally, the likelihood of wetlands being sources of nuisance flooding and the amounts of nuisance flooding they may produce likely depend on wetland configuration within the system. ...
The relationship between cities and wetland cover varies across the globe, with some cities converting wetlands to low‐ and high‐density urban cover and others preserving, conserving, or restoring wetlands, or constructing new ones. However, the scientific literature lacks studies relating changes in systemic flood risk in an urban stormwater management systems to changes in wetland cover. Furthermore, whether and how such relationships are affected by changing storm intensity under climate change is unknown. We present a case study on the effects of changes in urban wetland extent and storm intensity on flooding in an urban drainage system in Valdivia, Chile, under several co‐produced future scenarios and historical trends of development. We used data derived from stakeholder workshops and historical landcover to determine four plausible scenarios of urban development, plus one business‐as‐usual scenario, in Valdivia through the year 2080. Additionally, we used historical precipitation data and downscaled climate data to estimate event rainfall from extreme storms in the year 2080. We found that system flood volume and time the system was flooded increased with increasing wetland loss and rainfall volume. Mean rate and hour of peak discharge were unaffected by wetland loss. Infiltration's relative role in reducing flooding diminished as wetland loss increased. Cities may still experience dangerous and/or unacceptable flooding even with extensive wetland coverage and will likely need to pair conservation with additional improvements in their stormwater management systems and contributing watersheds.
... Moreover, specific actions have been developed to mitigate anthropogenic disturbances affecting wetland areas such as illegal land use, urbanization, trampling, burying ponds, water stress, alien species. These efforts aim to facilitate natural ecological successions (Manzano et al. 2019;Assefa et al. 2021). ...
Land-cover change dynamics were investigated in a Mediterranean coastal wetland to evaluate the long-term effectiveness of nature reserve management. A multitemporal analysis of land cover maps was conducted, utilizing visual interpretation of aerial orthophotos from the summer seasons of 1996, 2008, 2015, and 2021. Landscape changes were evaluated by transition matrices and chord diagrams. Maps were classified in accordance with CORINE land cover types at a fourth level of detail. The multitemporal analyses provided a comprehensive overview of landscape changes within the reserve over the past 25 years. The most notable changes were the increase of wetland areas and the reduction of agricultural and artificial areas. Moreover, seminatural vegetation constantly extended over time. These changes reflected the continuous management activities within the nature reserve, encompassing agreements for water supply, restoration projects, and measures to counteract illegality. These operational actions induced fine-grained ecological changes (outcomes at ecosystem level). This study highlighted the importance of remote sensing and landscape analysis, matched with fine-grained management data, as tool for long-term monitoring. Such an approach provides valuable support in evaluating the effectiveness of strategies promoted in nature reserves hosting wet coastal ecosystems of high conservation concern.
... For example, the conversion of forests into farmland may lead to reduced water sources and increased soil erosion, thereby diminishing the capacity for water regulation and soil conservation [48]. By simulating and predicting future LUCs, we can better anticipate trends in ecosystem service changes, providing essential foundations for developing sustainable development strategies [49]. Furthermore, the assessment of ecological risks and uncertainties must also consider the impacts of future LUCs. ...
With the rapid progress in urbanization and economic development, the impact of land use change (LUC) on ecosystem services is becoming increasingly significant. However, the accuracy of ecological risk assessment faces challenges due to the presence of uncertainty factors. Using the PLUS model, this study aims to simulate and predict land use changes (LUCs), focusing on the southern hilly regions in southeastern China as a case study, conducting an in-depth assessment of ecological risk uncertainty. Firstly, a spatiotemporal simulation of LUCs in the southern hilly region from 1990 to 2030 was conducted under multiple scenarios. Subsequently, differences in the spatial and temporal distribution of ecosystem service value (ESV) across different years and forecast scenarios in the southern hilly region were revealed, followed by a detailed analysis of the impact of LUCs on ESV. Finally, by calculating the Ecological Risk Index (ERI), the study systematically analyzed the evolution trend of ecological risk in the southern hilly region of China from 1990 to 2030. The main research findings are as follows: (1) the conversion proportions of different land use types vary significantly under different scenarios. Compared to 2020, under the 2030 National Development Scenarios (NDSs), there has been a slight decrease of around 3% in the total conversion area of farmland, forest, and grassland. However, under the Ecological Protection Scenario (EPS) and Urban Development Scenario (UDS) scenarios, there has been an increase in the area of forest and grassland, with a rise of approximately 1.5% in converted built-up land. (2) Western cities (e.g., Yueyang and Yiyang), central cities (e.g., Jiujiang), and northeastern cities (e.g., Suzhou) of China exhibit a relatively high ESV distribution, while ESV significantly decreased overall from 2010 to 2020. However, under the EPS and UDS, ESV shows a significant increasing trend, suggesting that these two scenarios may play a crucial role in ecosystem restoration. (3) The conversion of forest and water bodies to farmland has the most significant inhibitory effect on ESV, especially during the period from 1990 to 2000, providing substantial data support for relevant policy formulation. (4) From 1990 to 2030, ecological risk gradually increased in western, central, and southwestern cities of the southern hilly region, with the highest ecological risk values under the EPS scenario in northern cities (e.g., Chizhou and Tongling). Under the UDS scenario, there has been a significant decrease in ecological risk, providing valuable insights for future ecological conservation and sustainable development. However, a limitation lies in the need for further enhancement of the scenario’s simulation authenticity. This study offers a new perspective for understanding the impact of LUCs on ecosystem services and the uncertainty of ecological risks, providing crucial reference points for land resource management and the formulation of ecological conservation policies.
... The transformation of land use and land cover has resulted in alteration and loss of wetlands (Sarkar and Dana 2022;Das and Mehrotra 2023). Further, climate variability has affected spatial extent, hydrology, vegetation, and ecological dynamics (Assefa et al. 2021;Sibanda and Ahmed 2021;Mehta et al. 2022). Several studies have examined the impact of LULC changes on wetlands hydrology, ecology, and overall environmental health of wetland (Das and Mehrotra 2023;Singh et al. 2023;Roy and Mondal 2023). ...
Wetlands are significant landscapes that help in maintaining the ecological services, providing habitat for flora and fauna, controlling floods and regulating climate. Wetlands have been under constant threats due to urbanization and land use changes. The present study has examined the impact of land use/land cover (LULC) changes on spatio-temporal dynamics of Deepor Beel wetland, a Ramsar site in India. Multi-temporal Landsat satellite images for 32 years (1990–2022) were utilized to analyze the wetland dynamics. Wetland was delineated using modified normalized difference water index (MNDWI). Neural networks (Nnet), random forests (RF) and support vector machine (SVM) models were employed for preparing land use and land cover (LULC) maps. Water consistency was assessed using water presence frequency (WPF). The Landscape Fragmentation Tool (LFT) was utilized for computing various fragmentation indices. The findings revealed a consistent decline in wetland area from 15.16% in 1990 to 8.96% in 2022 primarily due to its transformation into built-up and agricultural lands. RF model was found more suitable than other models for LULC classification and change detection. Water presence frequency (WPF) analysis has shown marked variations in wetland area during pre- and post-monsoon seasons. Fragmentation analysis indicated that the number of patches has increased in periphery of wetland. Thus, this study calls for effective land use planning, reduction in wetland dependency of communities, creation of awareness among communities towards wetland restoration and conservation. The findings of the study may help the policymakers and conservationists for long-term sustainability and effective wetland management.
... First, the resolution of remotely sensed images is limited. Owing to the data vacancy, the remote sensing interpretation data acquired in the process of satellite image classification may have unnecessary errors, which may either underestimate or overestimate the GEP loss in the landscape change process (Assefa et al., 2021). Therefore, we recommend that future studies utilize satellite images with higher spatial resolution. ...
Environmental and socioeconomic drivers would alter landscapes, bringing various effects with different directions and magnitudes. Demonstrating these driving effects is key to relieving the conflicts between territorial vegetation restoration and regional economic growth. However, the relationship between ecological protection and economic development due to landscape dynamics has not been systematically demonstrated as environment is difficult to quantify by the monetary value. In this article, we explored the changes in gross ecosystem product (GEP) in the Three Gorges (TG) reservoir area and constructed a conceptual framework to explicate its driving mechanism. Our results suggested that topographic, soil, and climatic factors positively impact on GEP through their important effects on vegetation structure, distribution, and succession. Additionally, reforestation policies promote the conversion of farmland and grassland to forestland in the TG reservoir region, which was the main contributor to enhancing GEP. Conversely, socioeconomic factors negatively impact GEP, of which effects were mainly manifested by changes in the proportion of ecological land. Therefore, it is essential to maintain a suitable land use proportion in this region to optimize GEP, and we proposed a landscape restoration program to enhance four ecosystem productions. This article provides a reference for land resource allocation for environmental protection and sustainable development in ecologically fragile areas.
... Consequently, wetlands' ability to provide vital ecosystem services to people is being impaired by fast wetland loss and degradation (Bedo et al. 2022). The decline of environmental quality and the reduction of ecosystem services result in substantial economic losses (Arowolo et al. 2018;Assefa et al. 2021). Currently, the country is experiencing extreme land degradation, which makes a thorough understanding of ecosystem services' importance to rural communities imperative (Krause et al. 2017). ...
Wetland ecosystems provide services to numerous communities worldwide. However, anthropogenic pressure continues to escalate in many wetlands, resulting in the degradation of the ecosystem. The primary objective of this research is to evaluate the perceptions of local and indigenous people regarding ecosystem services provided and examine the drivers that are causing the Boyo wetland to change. The study employs a mixed research design that integrates both quantitative and qualitative analysis techniques, such as household questionnaire surveys (n = 178), focus group discussions (n = 5), key informant interviews (n = 20), and field observations. Participants have been selected through purposive and simple random sampling methods. In this study, the existing wetland ecosystem services are identified based on their observed importance at the local level, with provisioning services considered the most beneficial ecosystem services. We use the chi-square test to determine if differences exist among perceptions of the value of existing ecosystem services in the wetland depending on variables including gender and education level. While no significant differences exist for gender, we do find a statistically significant result for regulating and cultural services regarding respondent educational attainment. Higher-educated local people were more likely to have a good idea about these services. According to the respondents, the main drivers causing change that harms the services provided by the study wetland are siltation and population pressure. Based on this analysis, we recommend soil conservation measures and afforestation in the watershed area to prevent siltation, as well as education and outreach to help local communities better understand the challenges and benefits of local wetlands. In addition, an alternative livelihood option is necessary to reduce the growing population pressure.
... Our findings are consistent with previous studies that have observed an increase in builtup areas and a decrease in wetlands over time (Assefa et al. 2021, Li et al. 2022). This trend reflects the rapid urbanisation and expansion of human settlements within the Anambra River Basin, driven by population growth and economic development. ...
Land cover change and its consequences such as environmental degradation and biodiversity loss pose significant global challenges, including in Nigeria's Anambra River Basin. This study focuses on monitoring, predicting and understanding land cover changes in the basin from 1987 to 2018, with projections up to 2030. It explores the intricate relationship between population growth and land cover dynamics, aiming to contribute to sustainable land management practices and align with the Sustainable Development Goals (SDGs) for 2030. Using a combination of neural network classification and the CA-Markov model, the study analyses historical land cover data to identify significant transformations. Between 1987 and 2018, bare lands increased by 29%, vegetation increased by 14%, built-up areas increased by 128% and waterbodies increased by 10%, whereas there was a 58% decline in the extent of wetlands. The most significant transformation occurred in the wetlands, with a total of 1819.46 km 2 being converted to various land cover types. The results demonstrate remarkable shifts characterised by rapid urbanisation, substantial wetland loss and a decline in vegetation cover. Expectedly, population growth is found to be closely linked to the expansion of built-up areas while negatively impacting other land cover types. These findings underscore the urgent need for sustainable land management strategies that balance the demands of growing populations with the preservation of natural ecosystems and biodiversity. Furthermore, the study provides future projections that offer crucial insights for decision-makers involved in land use planning, biodiversity conservation and sustainable development.
... Human activities lead to the fragmentation of large-scale wetlands and the expansion of cultivated land from the edge of wetlands into the core area, affecting the core and edge morphology of wetlands, resulting in wetland erosion [62][63][64][65][66][67], and destroying the connectivity between wetlands [68]. Mao et al. [69] have proved that about 60% of China's lost natural wetlands were due to agricultural encroachment, and the phenomenon also occurred in other countries and regions of the world [70][71][72]. This explains the conversion of SMWs into agricultural land, which is cultivated by humans to meet the food supply, gradually transformed into small wetlands after human disturbance and fragmentation, and then artificially converted into cultivated land or paddy field for agricultural production. ...
... Especially in the Yellow River Delta, Yan et al. [74] found that the total area of wetlands in 2020 increased by about 516 km 2 compared with 1990, while the natural wetlands decreased by 391.6 km 2 , which mainly transformed into constructed wetlands such as aquaculture facilities and ponds. Assefa et al. [70] found that the acceleration of urbanization and the enhancement of environmental awareness of human-constructed wetlands such as wetland parks and sewage treatment plants have alleviated the loss of natural wetlands to some extent. In addition, the construction of reservoirs also affects the distribution of SMWs. ...
Comprehending the spatiotemporal dynamics and driving factors of small and micro wetlands (SMWs) holds paramount significance in their conservation and sustainable development. This paper investigated the spatiotemporal evolution and driving mechanisms of SMWs in the Yellow River Basin, utilizing buffer zones, overlay analysis, and the Geodetector model based on Landsat satellite images and an open-surface water body dataset from 1990 to 2020. The results revealed that (1) from 1990 to 2020, SMWs in the Yellow River Basin exhibited an overall pattern of fluctuation reduction. The total area decreased by approximately 1.12 × 105 hm2, with the predominant decline occurring in the 0–1 hm2 and 1–3 hm2 size categories. In terms of spatial distribution, SMWs in Qinghai and Gansu decreased significantly, while the SMWs in Inner Mongolia, Henan, and Shandong gradually increased. (2) From 1990 to 2020, SMWs were mostly converted into grassland and cropland, with some transformed into impervious water surface and barren, and only a small percentage converted into other land types in the Yellow River basin. (3) The alterations in SMWs were influenced by factors, with their interplay exhibiting nonlinear or bilinear enhancement. Among these factors, annual precipitation, elevation, and potential evapotranspiration were the primary natural factors influencing the changes in the distribution of SMWs. On the other hand, land use cover type, gross domestic product (GDP), and road distance were the main anthropogenic factors.
