{"title":"Spatiotemporal characteristics of human activity and land use on ecosystem service functions in mountainous areas of Northeast Guizhou, Southwest China","authors":"Quan Wang , Xuepiao Bai","doi":"10.1016/j.ecoleng.2024.107473","DOIUrl":"10.1016/j.ecoleng.2024.107473","url":null,"abstract":"<div><div>With the rapid advancement of urbanization and industrialization, intense land utilization in mountainous areas has led to ecological and environmental issues, and also causing a gradual degradation of ecosystem services. Investigating the spatiotemporal characteristics of human activities and land use on ecosystem services in mountainous areas holds significant practical importance for local ecological conservation and land management. This study utilizes human activity and land use models to evaluate the complex relationship between humans and land in the northeastern Guizhou, employs the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and the Modified Universal Soil Loss Equation (RUSLE) models to conduct an in-depth investigation into the spatiotemporal distribution of soil conservation (SC), water yield (WY), carbon sequestration (CS), habitat quality (HQ), and landscape aesthetics (LA). Besides, we utilized the Pearson correlation coefficient and spatial bivariate models to scrutinize the spatial heterogeneity and interactions among these ecosystem services. The results revealed a significant escalation in the intensity of human activity and land use within the study area, with values rising from 0.483 and 316 in 2000 to 0.695 and 351 in 2020, respectively. For 2000–2020, the added value of SC and WY experienced a change of 1.179 t‧hm<sup>−2</sup> and 118.503 mm respectively, while the CS, HQ, and LA have largely remained stable. The spatial distribution of ecosystem service functions exhibited distinct patterns of trade-offs and synergies. The ecosystem's multifunctional benefits were predominantly concentrated in the northern sector of the study area, with the maximum migration distance of class IV hotspots recorded at 70.431 km. Over time, the impact of human activities and land use on ecosystem services has been escalating. Studying the interactions between human activities and land use and their impact on ecosystem services can help us to develop land development policies and ecological management strategies.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107473"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhicheng Jiang , Dong Cui , Yancheng Yang , Wenxin Liu , Zununjan Zinhar , Jiangchao Yan , Jianghui Liu , Jing Cao , Minru Zhang , Qiaoli Wang
{"title":"Characteristics of soil arthropod communities and soil health in ‘Shushanggan’ apricot forests after soil bioengineering remediation in the riparian zone of the Ili River Valley evaluation","authors":"Zhicheng Jiang , Dong Cui , Yancheng Yang , Wenxin Liu , Zununjan Zinhar , Jiangchao Yan , Jianghui Liu , Jing Cao , Minru Zhang , Qiaoli Wang","doi":"10.1016/j.ecoleng.2024.107505","DOIUrl":"10.1016/j.ecoleng.2024.107505","url":null,"abstract":"<div><div>To investigate the impact of riparian soil bioengineering restoration on the soil ecological environment, this study used soil arthropods as bioindicators to assess and monitor the restoration effects in the ‘Shushanggan’ apricot orchard. The aim was to explore and develop long-term, sustainable restoration strategies to ensure the stability of soil quality., this study focused on the ‘Shushanggan’ apricot forests located in the Guozigou River, a tributary of the Ili River in Huocheng County, Yili Prefecture. The restoration sites with different durations of 4, 8, 10, and 14 years were selected, while the surrounding uncultivated land served as the control. The soil arthropods were separated using a dry-funnel extraction method, and the community characteristics of soil arthropods were investigated, employing the soil biological quality (QBS-ar) index for soil health assessment. The results revealed that in both spring and summer, the total number of soil arthropods was highest in the 14-year-old ‘Shushanggan’ apricot forests, while the highest number of species was observed in the 4-year-old forests. The similarity coefficient of soil arthropod communities between the uncultivated land and ‘Shushanggan’ apricot forests indicated extreme dissimilarity during spring and ranged from extremely dissimilar to moderately similar during summer, displaying a substantial disparity between the two seasons. The QBS-ar index of soil arthropods was highest in the 14-year-old ‘Shushanggan’ apricot forests, indicating better soil health in the surface soil compared to the deeper layers. These findings demonstrate that soil biotechnology has improved the soil ecological environment in riverbanks, resulting in significant changes in the community structure of soil arthropods. It has also contributed to an increase in soil arthropod diversity and improved soil health. Thus, this study provides scientific evidence for soil biotechnology restoration in the Ili River Valley, management of ‘Shushanggan’ apricot forests, and soil ecological conservation.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107505"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eduardo González-Sargas , Martha Gómez-Sapiens , Osvel Hinojosa-Huerta , Stefanny Villagomez-Palma , Alejandra Calvo-Fonseca , Joanna Grand , Timothy D. Meehan , Chris Dodge , Pamela L. Nagler , Carlos Restrepo-Giraldo , Carlos Nieblas , Angela Meléndez , Roberto Real Rangel , Patrick B. Shafroth
{"title":"Corrigendum to “Avian communities respond to plant and landscape composition in actively revegetated floodplains of the Colorado River delta in Mexico” [Ecological Engineering 205 (2024) 107266].","authors":"Eduardo González-Sargas , Martha Gómez-Sapiens , Osvel Hinojosa-Huerta , Stefanny Villagomez-Palma , Alejandra Calvo-Fonseca , Joanna Grand , Timothy D. Meehan , Chris Dodge , Pamela L. Nagler , Carlos Restrepo-Giraldo , Carlos Nieblas , Angela Meléndez , Roberto Real Rangel , Patrick B. Shafroth","doi":"10.1016/j.ecoleng.2024.107508","DOIUrl":"10.1016/j.ecoleng.2024.107508","url":null,"abstract":"","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107508"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Response of grass covers for dikes to coastal stressors during establishment phase","authors":"Jochen Michalzik, Maike Paul, Torsten Schlurmann","doi":"10.1016/j.ecoleng.2024.107488","DOIUrl":"10.1016/j.ecoleng.2024.107488","url":null,"abstract":"<div><div>Grass covers on dikes are subjected to a multitude of controlled and uncontrolled environmental stressors that can affect its vegetation development. Controlled stresses are applied during dike maintenance (e.g. mowing) to establish high coverage and a dense root system. Uncontrollable stresses during storm surges (e.g. flooding and wave loading) are likely to disturb this development. This species composition-based study analyses stress responses and their consequences for the ecological enhancement of grass covers in terms of dike safety. The responses of four different grass covers with increasing species numbers were investigated under three controlled experimental conditions, mimicking North Sea storm surge season in an outdoor wave-basin. We found significant differences in vegetation development indicating a shift of biomass from roots to shoots in response to flood stress. Resulting losses in the grass cover resistance were only minor for all grass covers. When additional wave stress was introduced no significant differences in root biomass were observed compared to the control group without flood or wave stress. The more herb and legume dominated grass covers seem to provide less erosion resistance for dike safety than the grass-dominated ones, as they develop the desired coverage slower and tend to have a lower shear strength. In conclusion, ecological enhancement by moderately increasing the number of species in the grass cover is possible without affecting dike safety. Evidence of disturbance in vegetation development highlight that thresholds and indicators for the early detection of stress responses need to be further investigated regarding the predicted intensification of uncontrolled environmental stressors. It is emphasised that long-term studies and adaptive monitoring are required to avoid unforeseen consequences by overloading the ability of grass covers to cope with and recover from coastal stressors and to find the optimal combination of ecological enhancement and dike safety.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107488"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Pinotti , L. Gaucher , V. Fleitas , L. Boccardi , G. Goyenola
{"title":"Aluminum compounds as a management tool for Eutrophic Lakes: State of the art","authors":"G. Pinotti , L. Gaucher , V. Fleitas , L. Boccardi , G. Goyenola","doi":"10.1016/j.ecoleng.2024.107503","DOIUrl":"10.1016/j.ecoleng.2024.107503","url":null,"abstract":"<div><div>Chemical applications in eutrophic lakes, known as geoengineering interventions, have been utilized for decades. This review provides an overview of the applications of aluminum compounds for lake rehabilitation based on numerous case studies obtained through a systematic search methodology. The results reviewed indicate that, given appropriate doses, aluminum compounds have generally proven effective in reducing the internal phosphorus load and preventing cyanobacterial blooms. However, it is important to acknowledge certain limitations and cases where undesired effects have been detected (such as acidification and fish mortality), emphasizing the need to design off the applications carefully. Polyaluminum chloride (PAC) is preferred mainly due to its higher pH buffering capacity, flocculation efficiency, and avoidance of sulfate addition and interference in sulfur cycles. Dose calculation should be based on the internal load criterion, with limitations on the amount dosed in each application. Direct application in the water column is the most reported methodology and has shown logistic advantages. Climate and weather knowledge are relevant for defining timing. However, varied treatment efficiencies have been reported, so it is necessary to conduct comprehensive pre-application experiments. It is also recommended to include mesocosm-scale testing as a preliminary stage before applying treatments to the entire lake. The review also discusses the effects on water characteristics, the factors that affect the efficacy and longevity of applications, and the use of aluminum compounds in combination with other substances for ballasting or capping purposes. Furthermore, the interaction of such treatments with biota is also considered. We conclude that the intervention strategy should consider the systemic and functional perspective, as well as each lake's characteristics. The lake-specific nature of aluminum treatments underscores the importance of characterizing individual lakes before designing applications or extrapolating results to other systems.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107503"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The multidimensional influences of environmental factors on carbon storage: Evidence from Zagros Forests of Iran","authors":"Maziar Haidari , Yaghoub Iranmanesh , Abolfazl Jaafari , Mehdi Pourhashemi , Jalal Henarah , Farhad Jahanpour , Arash Derikvandi , Behrouz Fani","doi":"10.1016/j.ecoleng.2025.107523","DOIUrl":"10.1016/j.ecoleng.2025.107523","url":null,"abstract":"<div><div>Effective carbon storage in forests is crucial for mitigating climate change by capturing and holding carbon dioxide, aligning with the broader goals of ecosystem restoration and carbon neutrality central to Nature-based Solutions (NbS). Different forests have varying carbon storage capacities based on their unique characteristics and a range of multidimensional influences from environmental factors, necessitating region-specific management strategies. In this study, we explored the multidimensional influences on carbon storage among forests distributed across three provinces in the Zagros Forests of Iran: West Azerbaijan, Kurdistan, and Lorestan. Data from 10 monitoring sites revealed significant variations in carbon storage between above-ground and below-ground components across the provinces. West Azerbaijan exhibited the highest overall carbon storage, while Lorestan and Kurdistan showed distinct patterns in specific carbon storage components. Organic carbon, total nitrogen, relative humidity, and precipitation emerged as the strongest positive influencers of carbon storage, whereas factors such as gravel content, temperature, and evaporation had negative impacts. Overall, our results suggested that the carbon storage capacity of a region is closely tied to the characteristics of a province, which is a critical consideration for NbS. Interestingly, provinces with higher density and larger trees were found to have superior carbon storage, underscoring the importance of targeted conservation efforts. These results align with the principles of NbS by highlighting the need for region-specific forest management and carbon sequestration strategies to maximize carbon storage and support ecosystem restoration.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107523"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhaozhe Chen , Jiyoung Lee , Molly Mills , Abigail Volk , Ozeas S. Costa Jr.
{"title":"Field-scale artificial floating islands reduces cyanotoxin from residential raw sewage treatment basin","authors":"Zhaozhe Chen , Jiyoung Lee , Molly Mills , Abigail Volk , Ozeas S. Costa Jr.","doi":"10.1016/j.ecoleng.2025.107543","DOIUrl":"10.1016/j.ecoleng.2025.107543","url":null,"abstract":"<div><div>Microcystin (MC) is the most prevalent and persistent cyanotoxin associated with freshwater harmful algal blooms (HABs), posing substantial health risks to both humans and aquatic ecosystems. Artificial floating islands (AFIs) offer a promising solution to MC reduction. In this study, we evaluated the effectiveness of a field-scale AFI system in reducing MC concentrations, using two native aquatic plants, <em>Carex comosa</em> (bristly sedge) and <em>Eleocharis obtusa</em> (blunt spike-rush), installed in the equalization basin of a wastewater treatment plant for the preliminary treatment of residential raw sewage. Over a three-month period during late summer and fall, we monitored MC concentrations, physico-chemical parameters, nutrient levels, and plant biomass. The results showed that the AFI system achieved up to a 77.9 % reduction in MC during peak plant growth. Additionally, the relative abundance of cyanobacteria decreased from 27.7 % to 4.5 % following AFI treatment during this period. We identified precipitation as a key factor influencing MC reduction rates in natural settings (<em>r</em> = − 0.56, <em>p-value</em> = 0.06 between accumulated precipitation and reduction in MC concentrations). Despite the presence of MC, plant growth and MC reduction were not significantly hindered by MC toxicity (<em>r</em> = 0.01, <em>p</em>-value = 0.99). While temperature and nutrient concentrations did not directly affect MC reduction rates, they did influence plant biomass production, which in turn impacted AFI performance. <em>C. comosa</em> exhibited greater potential for MC reduction compared to <em>E. obtusa</em>, due to its faster growth and higher biomass production. This study is the first investigation of field-scale AFIs targeting MC as the primary pollutant, emphasizing their feasibility as a sustainable and effective strategy for managing cyanotoxin during HABs.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107543"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zongxing Li , Qiao Cui , Qi Feng , Bin Qiao , Juan Gui
{"title":"The variation of soil water content and its driving factors in different melting periods in the Three River Headwaters Region: A implication for vegetation restoration","authors":"Zongxing Li , Qiao Cui , Qi Feng , Bin Qiao , Juan Gui","doi":"10.1016/j.ecoleng.2024.107495","DOIUrl":"10.1016/j.ecoleng.2024.107495","url":null,"abstract":"<div><div>The variation of soil water content (SWC) and its driving factors are usually vital in developing vegetation restoration and ecological protection in permafrost regions. Here, to understand how SWC varied with time and space in different soil layers and to propose strategies of vegetation restoration in the Three River Headwaters Region, we collected 955 soil samples at a regional scale during 2019 to 2021. The results indicated that SWC was higher in the southeast of the region, but lower in the northwest, and the distribution range of the high value area of SWC was the largest in August and the least in July. It showed a decreasing trend with the increase of soil depths, SWC in June was 17.19 %–26.13 %, in July was 18.30 %–22.15 %, in August was 19.74 %–30.47 %, and in September was 19.20 %–27.33 %, and the mean SWC of 0–80 cm was August > September > June > July. At the entire regional scale, soil bulk density exerted a first order control on the SWC variation. Moreover, slope gradient, normalized difference vegetation index, temperature, and altitude played important roles in affecting SWC in different melting periods. The results provided effective implications for proposing corresponding strategies of vegetation protection and restoration in different melting periods. Our results provided scientific support for water resources management, vegetation restoration, and ecological protection in this region.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107495"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Esraa A.M. Mohamed, Ahmed M. El-Baha, Ahmed A.A. El-Settawy, Nader D. Shetta, Mohamed Z.M. Salem
{"title":"Seaweed extract and biological fertilizer to stimulate the growth of Khaya senegalensis irrigated with agricultural drainage water in greenhouse conditions for a sustainable forest plantation industry in Northern Egypt","authors":"Esraa A.M. Mohamed, Ahmed M. El-Baha, Ahmed A.A. El-Settawy, Nader D. Shetta, Mohamed Z.M. Salem","doi":"10.1016/j.ecoleng.2025.107531","DOIUrl":"10.1016/j.ecoleng.2025.107531","url":null,"abstract":"<div><div>Due to the global deficiency in water, alternate water sources, such as agricultural drainage water (ADW), are now used to irrigate plants, particularly timber trees. A greenhouse experiment was carried out to assess the effects of irrigation schedules using ADW with or without Nile water (NW) on the growth of <em>Khaya senegalensis</em> seedlings. Additionally, the effects of mineral fertilizer (NPK) contains urea (46 % N), superphosphate (15.5 % P<sub>2</sub>O<sub>5</sub>), and potassium sulfate (50 % K<sub>2</sub>O) at a dose of 1 g N, 0.5 g P<sub>2</sub>O<sub>5</sub>, 0.5 g K<sub>2</sub>O/plant, seaweed extract (SE) at 7 mL/L from a commercial wild brown seaweed, <em>Sargassum</em>, and a biofertilizer Top Strains (TS)® at 30 mL/plant, as well as their combination on growth parameters of <em>K. senegalensis</em> seedlings were assessed. The plants that were irrigated with 100 % NW and fertilized with NPK + SE displayed the highest values in terms of shoot height (134.6 cm), leaf dry weight (123.28 g), stem dry weight (122.005 g), root dry weight (131.84 g), total dry weight (377.138 g), shoot/root ratio (1.858), shoot growth rate (4.53 cm/month), leaf area (447.176 cm<sup>2</sup>), leaf length (39.32 cm), number of leaves/plant (70.2), and number of leaflets/leaf (17). The plants irrigated with 100 % ADW and fertilized with NPK + SE had the highest chlorophyll content (57.159 SPAD units), followed by those irrigated with 50 % NW + 50 % ADW. The biomass production of <em>K. senegalensis</em> was moderately affected by the biofertilizer Top Strains (TS)®. The SE was subjected to chemical analysis using GC–MS, HPLC, and amino acid analyzers revealing the presence of several bioactive compounds. These included benzyl salicylate, oleic acid methyl ester, protocatechuic acid, pyrogallol, and benzoic acid, as well as the amino acids ammonia, alanine, glycine, and lysine, and the water-soluble vitamins thiamine and riboflavin. The biomass production from <em>K. senegalensis</em> was somewhat affected by adding SE, TS, or NPK fertilizers with irrigation regimes. Significantly, when <em>K. senegalensis</em> plants received irrigation with 100 % NW + 50 % ADW and treated with NPK + SE, most of their vegetative characteristics improved. The results have proved that fertilizer treatments and alternative water regimes are environmentally friendly and have economic applications to maximize the growth and yield of <em>K. senegalensis</em>.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107531"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhancing chemical and physical properties of bauxite residue: A one-year assessment using Açaí Waste and Gypsum in in-situ rehabilitation","authors":"Yuuki Silveira Miura , Jan Mulder , Valentina Zivanovic , Ronan Courtney , Adriana Souza , Hogne Stubhaug , Gudny Okkenhaug","doi":"10.1016/j.ecoleng.2024.107500","DOIUrl":"10.1016/j.ecoleng.2024.107500","url":null,"abstract":"<div><div>Bauxite residue (BR) from alumina production poses significant environmental challenges, including establishment of a vegetation cover, due to its high alkalinity, salinity, and trace element content. The practice of using topsoil as a cover in bauxite residue storage facilities (BRSF) is unsustainable due to mounting demands on natural topsoil reserves. As an alternative, blending BR with gypsum and organic waste may offer a cost-effective method to improve its chemical and physical properties important to foster better conditions for plant growth. Contrary to previous investigations, which have focused primarily on weathered BR, this study was done on fresh, filter-pressed BR, resulting from more modern, and now commonly used, technologies in alumina production. Here, we assess the in-situ impact of a mixture of gypsum and açaí berry waste one-year after its application to a BRSF of non-weathered, filter-pressed BR, in the tropical climate of Northern Brazil. The site has an average annual precipitation of 2085 mm, and the study tested the effect of additions of various mixtures of gypsum (0 %, 5 %, 8 %, and 13 % by weight) and açaí waste (0 % and 8 % by weight). Results showed that the treatments with gypsum and açaí waste successfully reduced pH levels from 12.0 to 7.7–8.1. Also, Electrical conductivity (EC) reduced significantly and achieved the rehabilitation goal (4mS/cm) after month 4 of the experiment. The exchangeable sodium percentage (ESP) values decreased from 98.8 % in fresh BR to 18.0 % in BR with 8 % gypsum, and to 8.4 % in treatment with 8 % gypsum and 8 % acaí waste. Gypsum treatment also decreased the fraction of unstable aggregates of BR from ∼70 % to ∼40 %. Despite precipitation playing an important role in lowering pH, EC and alkalinity, we found that the combined use of gypsum and açaí waste was the most effective in enhancing BR properties by reducing pH and ESP and increasing aggregate stability. As expected, organic material like açaí seed waste adds both organic matter and major plant nutrients to BR, thus playing a key role in enhancing soil quality, and in establishing a vegetation cover. This study offers insights into the initial transformations in amended BR and provides a solid foundation for developing closure strategies using gypsum and available and low-cost organic wastes as soil enhancers.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"212 ","pages":"Article 107500"},"PeriodicalIF":3.9,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143165119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}