Ecological Engineering最新文献

{"title":"Predicting suitable habitats and carbon storage potential of mangroves: A case study in Zhanjiang, China","authors":"Zeyu Lin ,&nbsp;Wenxiao Su ,&nbsp;Xiaowei Cui ,&nbsp;Long Wei ,&nbsp;Jianxiang Feng","doi":"10.1016/j.ecoleng.2025.107881","DOIUrl":"10.1016/j.ecoleng.2025.107881","url":null,"abstract":"<div><div>Carbon emissions are one of the important factors leading to the climate crisis, and mangroves play an important role in enhancing carbon sink. However, predicting suitable growth areas for mangroves and assessing their carbon sink potential remains a scientific challenge. Based on this, we developed an integrated analytical framework, that combines the MaxEnt model, spatial autocorrelation analysis, Geodetector, and InVEST model. This framework was used to investigate the mangrove distribution patterns, the influence of environmental factors on their suitable habitats, and carbon storage characteristics. The total area of highly suitable mangrove habitat was 139.9 km², exhibiting significant spatial clustering characteristics, with high-suitability regions showing pronounced aggregation (Moran's <em>I</em> = 0.773). Habitat suitability was strongly influenced by the single factor of topographic factor (DEM contribution rate: 44.2 %); precipitation emerges as the central interactive factor, exhibiting strong synergistic relationships with potential evapotranspiration (q = 0.91), temperature (q = 0.87), and leaf area index (q = 0.85), collectively shaping ecological suitability; although topographic and climatic factors primarily govern habitat suitability, carbon storage analysis highlighted Gaoqiao town in the northwest as a priority area for mangrove expansion, owing to its high carbon storage potential (30.1 %). This study provides multidimensional decision-making support for precision restoration of coastal wetlands and implementation of carbon neutrality strategies.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107881"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837118","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":"Performance and application investigation of a hybrid surface-subsurface flow constructed wetland for in-situ water purification in small-micro rivers","authors":"Acong Chen ,&nbsp;Yimei Zhang ,&nbsp;Jiahui Zhao ,&nbsp;Penghui Liu ,&nbsp;Yi Pan ,&nbsp;Yidi Chen ,&nbsp;Kunfeng Ye ,&nbsp;Mingjie Yang ,&nbsp;Yanchun Deng","doi":"10.1016/j.ecoleng.2025.107882","DOIUrl":"10.1016/j.ecoleng.2025.107882","url":null,"abstract":"<div><div>Small-micro rivers, characterized by low water volume, poor mobility, and limited self-purification capacity, face significant eutrophication risks from non-point source pollution. Conventional ex-situ treatment methods are often costly and maintenance-intensive. This study introduces an in-situ hybrid constructed wetland that combines surface flow and subsurface flow processes, utilizing the natural topography of small-micro rivers to enable multi-directional water movement without lifting facilities. After stable operation, microbial analysis indicated enrichment of functional microorganisms involved in nitrogen and phosphorus metabolism, such as <em>Dechloromonas</em> (3.2–5.0 %) and <em>Hyphomicrobium</em> (1.0–1.7 %). The system achieved removal loads of 1.22 ± 0.13 g/(m²·d) for <span><math><msubsup><mi>NH</mi><mn>4</mn><mo>+</mo></msubsup><mo>−</mo><mi>N</mi></math></span> and 0.11 ± 0.02 g/(m²·d) for TP, significantly reducing eutrophication and enhancing self-purification capacity. Operationally, it requires no electricity or material consumption, with maintenance limited to periodic replanting of aquatic vegetation and substrate cleaning, resulting in low construction (approximately 820 CNY/m²) and operational costs. This approach provides an eco-friendly and economical solution for improving regional ecological health and offers practical guidance for rehabilitating similar small-micro water bodies.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107882"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787909","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":"Study on the rainfall erosion mechanisms and protection technology induced by short-duration intense rainfall in open-pit coal mine dump slopes","authors":"Wei Liu ,&nbsp;Xiangtian Xu ,&nbsp;Xiaoyu Yan ,&nbsp;Zhenyu Wang","doi":"10.1016/j.ecoleng.2025.107890","DOIUrl":"10.1016/j.ecoleng.2025.107890","url":null,"abstract":"<div><div>Short-duration intense rainfall has become a leading trigger for shallow failures in open-pit mine dump slopes, causing surface erosion, shallow slides (&lt;5 m), and operational hazards. This study aims to investigate the failure mechanisms associated with such rainfall events and evaluate a cooperative protection strategy combining Polyvinyl Alcohol (PVA) material with <em>Salix psammophila</em> (<em>S. psammophila</em>) sand barriers. To this end, twelve artificial rainfall tests were conducted on slopes with angles of 37° and 43°, under rainfall intensities of 70, 80, and 90 mm/h. The results indicate that <em>S. psammophila</em> sand barriers alone reduce erosion effectively only under moderate rainfall (&lt;80 mm/h), with erosion area ratios increasing from 34.3 % to 65.0 % under higher intensities. In contrast, PVA-treated slopes, forming a 2–3 cm hardened surface layer, demonstrated zero erosion and infiltration across all conditions. Furthermore, the cooperative PVA + Salix system outperformed individual measures, enhancing both mechanical stability and ecological potential. Scanning electron microscope (SEM) analysis showed that PVA creates a bonded membrane with soil particles, thereby increasing cohesion and resisting washout. Moisture sensors and infiltration depth tracking revealed that PVA drastically reduced infiltration velocity and delayed soil saturation. A four-stage failure model—initial infiltration, differential settlement, tension cracking, and shallow sliding—was proposed to explain the observed failure patterns. The combined protective approach significantly mitigates erosion risk, particularly under extreme rainfall, and offers a promising solution for sustainable slope management in mining regions.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107890"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880668","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":"Association of tidal channel tributaries with mainstem meander bends: Landform patterns to inform tidal marsh restoration design","authors":"W. Gregory Hood","doi":"10.1016/j.ecoleng.2025.107878","DOIUrl":"10.1016/j.ecoleng.2025.107878","url":null,"abstract":"<div><div>Species recovery and coastal resilience programs are spending hundreds of millions of dollars on coastal habitat restoration, particularly for tidal marshes. Tidal channels are central to tidal marsh function, and fortunately quantitative design guidance is available for how many and what size tidal channels are appropriate for a marsh restoration footprint. But guidance on where those channels should be located within the restoration footprint and how the channel networks should be structured is more limited. Inappropriately locating new tidal channels could result in restoration failure, if the channels are not sustainable (i.e., fill with sediment) in their chosen locations. Using natural tidal landforms as a template for restoration design can help minimize the risk of channel design failure. Excavating 2nd- or higher-order channels will require making decisions on where channel tributaries should be located. To address this design issue, I examined three distinct tidal marsh systems (the Skagit Delta in Washington State, USA; Ochlockonee Bay in Florida; and Tubul-Raqui in Chile) for patterns in tidal tributary channel locations. The results indicate that tributary channels are randomly encountered along the mainstem channel for large channels, but for small channels they are disproportionately located on the concave banks of meander bends, and they are generally larger in these locations. Design of tidal channel networks that mimics natural landforms should accelerate restoration site maturation and development of maximal hydraulic and ecological function.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107878"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145734593","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":"Event- and annual-scale precipitation extremes enhance groundwater recharge at the ecological restoration catchment of hilly and gully region","authors":"Meina He ,&nbsp;Yunqiang Wang ,&nbsp;Yali Zhao ,&nbsp;Li Wang ,&nbsp;Ziliang Zhang ,&nbsp;Yi Song ,&nbsp;Pingping Zhang ,&nbsp;Zimin Li","doi":"10.1016/j.ecoleng.2025.107868","DOIUrl":"10.1016/j.ecoleng.2025.107868","url":null,"abstract":"<div><div>Precipitation extremes and ecological restoration projects significantly influenced hydrological processes by mitigating or aggravating groundwater depletion within the Earth's critical zone. However, scientific evidence remains limited due to the strong dependence of deep recharge on both unsaturated zone thickness and precipitation event magnitude. Here, we analyzed seven-year field datasets encompassing precipitation, soil water content (SWC), surface water (reservoir water), and groundwater from an ecological restoration catchment on the Chinese Loess Plateau. Precipitation extremes triggered deep hydraulic connectivity between the unsaturated and saturated zones mainly through preferential flow pathways, as evidenced by depleted of δ¹⁸O, increased of SWC profiles, and rising water table. Temporal-spatial patterns of SWC (0–4000 cm profile) revealed preferential flow pathways on a sunny slope with recharge efficiency regulated by precipitation patterns and topography. In the gully, water tables showed a positive correlation with precipitation amount, duration, and initial SWC. These hydrological drivers induced significant differences in water table changes among precipitation years. In contrast, the slope (0–500 cm profile) maintained persistent water deficits with limited recharge response, despite precipitation inputs (except for a 167.7-mm event). Furthermore, precipitation variability coupled with plant root uptake altered the vertical soil water gradient, with the 200–300 cm layer functioning as a hydraulic buffer. However, prolonged drought triggered an accelerated water table recession at 60.8 mm/year, while creating carry-over soil water deficits that extended beyond dry years, sustaining 15.4 mm/year depletion even in the following normal year. When considering the saturated zone contribution, total recharge rates demonstrated the positive hydrological feedback of ecological restoration projects to annual precipitation, accounting for 45 % of precipitation (327.8 mm/year) during a wet year. Therefore, it can be inferred that event- and annual-scale precipitation extremes enhance groundwater recharge at the ecological restoration catchment. These findings provide critical scientific support for maintaining groundwater sustainability in such systems.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107868"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145683607","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":"Consequences of the senescence growth phase on the performance of treed bioretention cells","authors":"Jessica Dhami ,&nbsp;Caterina Valeo ,&nbsp;Jianxun He (Jennifer) ,&nbsp;Angus Chu","doi":"10.1016/j.ecoleng.2025.107879","DOIUrl":"10.1016/j.ecoleng.2025.107879","url":null,"abstract":"<div><div>Bioretention cells vegetated with trees were studied to understand the changes in performance for mitigating stormwater quantities and qualities during the senescence period. Stormwater runoff simulations were conducted in a temperate climate for 1.1-, 1.5- and 2-year return period storm events applied to field-based treed bioretention cells planted with a mix of <em>Betula nigra</em>, <em>Betula nana</em>, and <em>Salix lutea</em> trees, and grassed bioretention cells planted with turf grass. Eighteen separate storm events (six for each return period) were applied at various times during the 2020 summer growth period starting with the onset of senescence in late August to early September through to abscission in early October. Changes in water quality and quantity performance were analyzed over the senescence period for several parameters including water volume retention, chemical oxygen demand, total nitrogen (TN), total organic nitrogen (TON), total phosphorus (TP), orthophosphate, and total suspended solids (TSS) using non-parametric statistical tests. These were supported with additional analysis of daily evapotranspiration (ET) and antecedent moisture content (AMC). Correlations with the timing of senescence on the treed bioretention cell's performance were visible and significant (α = 0.05) over the testing period for water retention, TP, TN and orthophosphate. However, these results were not observed, or significant, for the grassed cell. The analysis showed that the treed cell's contribution to contaminant removal is highly correlated with changes in ET and AMC; whereas the grassed cell showed changes correlated only to AMC. This work demonstrates that the senescence period will lead to diminished water quantity retention and changes in nutrient retention and other stormwater contaminants from bioretention cells vegetated with trees.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107879"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787839","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":"How to minimize greenhouse gas emissions in Sphagnum re-vegetation areas - the role of topsoil removal","authors":"Caroline Daun,&nbsp;Greta Gaudig,&nbsp;Vytas Huth,&nbsp;Matthias Krebs,&nbsp;Gerald Jurasinski","doi":"10.1016/j.ecoleng.2025.107884","DOIUrl":"10.1016/j.ecoleng.2025.107884","url":null,"abstract":"<div><div>Drained peatlands are major sources of greenhouse gases (GHG). To counteract this effect, drained peatlands must be rewetted. Rewetted peatlands can be left to their own devices (wilderness development/restoration) or continued to be used for agriculture (= paludiculture). <em>Sphagnum</em> is a key genus for bog restoration and paludiculture on bogs. For successful <em>Sphagnum</em> establishment on rewetted bogs formerly used as grassland, it is recommended to remove the top layer of degraded peat. However, topsoil removal will cause additional GHG emissions and therefore should be minimized. In this study, we assess the climate effects of 30 cm and less topsoil removal on former bog grassland. For this, we measured GHG emissions with closed chambers where <em>Sphagnum</em> has been directly applied on the rewetted, mulched grassland (“Without topsoil removal” = TSR0) or on areas with topsoil removal of 5–10 cm (TSR5) and 30 cm (TSR30) depth. Over the entire study year, TSR5 and TSR30 were GHG sinks of −5.7 ± 1.2 t ha⁻¹ a⁻¹ and −4.5 ± 0.6 t ha⁻¹ a⁻¹ (in CO₂-eq), respectively. In contrast, TSR0 was a strong source of CH₄ resulting in a net GHG budget of 43.7 ± 7.4 t ha⁻¹ a⁻¹ due to the rewetted topsoil being rich in labile organic compounds. With a share of 80 % <em>Sphagnum</em> fields, 5 % ditches and 15 % causeways in the whole system TSR5 would emit the least GHGs of 0.9 ± 1.2 t ha⁻¹ a⁻¹, because with less topsoil removal, the share of <em>Sphagnum</em> production fields can be increased. TSR5 would thus be the most climate-friendly and cost-effective approach for raised bog restoration and for <em>Sphagnum</em> paludiculture following drainage-based, agricultural use.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107884"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787840","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":"Long-term ecological recovery of a minespoil watershed: Hydrological, vegetation, and carbon stock assessment","authors":"Jag Mohan Singh Tomar ,&nbsp;Anupam Barh ,&nbsp;Raj Kumar ,&nbsp;Deepak Singh ,&nbsp;Ranjeet Singh ,&nbsp;Dinesh Jinger ,&nbsp;R.K. Singh ,&nbsp;Rajesh Kaushal ,&nbsp;Sneha Dobhal ,&nbsp;M. Madhu","doi":"10.1016/j.ecoleng.2025.107883","DOIUrl":"10.1016/j.ecoleng.2025.107883","url":null,"abstract":"<div><div>Mining-induced land degradation severely disrupts ecosystems through the loss of vegetation diversity, accelerated erosion, soil and water contamination, and alteration of landforms. Although numerous reclamation initiatives have been undertaken worldwide, evidence on their long-term ecological effectiveness in terms of ecosystem recovery remains limited. This study evaluated the prolonged impacts of rehabilitation measures implemented in a minespoil watershed in northwestern India, focussing on soil- and vegetation-based interventions, and their influence on the hydrological stability, vegetation dynamics, species diversity, carbon sequestration potential, and water quality. The results indicated a substantial improvement in hydrological stability, with monsoon runoff declining from 57 % in 1984 to 25 % in 2023, and debris outflow reducing from 550 t ha⁻¹ in 1984 to nearly zero by 2023. The vegetation cover increased markedly from 10 % (pre-rehabilitation) to 95 %, particularly on the middle and lower slopes. Similarly, species diversity and richness exhibited consistent increased trends after the implementation of rehabilitation measures. Vegetation analysis identified <em>Acacia catechu</em> as a dominant species, followed by <em>Leucaena leucocephala</em> and <em>Toona ciliata</em>, all of which played a major role in the recovery of minespoil land. As an indicator species, <em>Acacia catechu</em> exhibited substantial growth, with tree height increasing from 5.37 m to 11.9 m and girth from 33.25 cm to 136.6 cm over 15 year. Similarly, the NDVI increased from 0.58 to 0.82 between 1991 and 2023, while model-derived carbon stock increased from 2.15 Mg C ha⁻¹ to 5.21 Mg C ha⁻¹ over the same period. However, water quality assessments indicated elevated levels of TDS (1652 ppm), salinity (1920 ppm), calcium, and magnesium, rendering the water unsuitable for irrigation and direct human consumption. Overall, the present findings demonstrate that long-term rehabilitation measures are highly effective in restoring minespoil lands by improving hydrological regulation, enhancing vegetation cover and species diversity, and significantly increasing carbon sequestration.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107883"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880667","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":"An Everglades water quality recovery model","authors":"Robert Kadlec ,&nbsp;John Juston","doi":"10.1016/j.ecoleng.2025.107880","DOIUrl":"10.1016/j.ecoleng.2025.107880","url":null,"abstract":"<div><div>Little is known of recovery times for nutrient impacted wetlands when excess inputs are removed. Here we model 35-years of water quality phosphorus (P) data from a well-studied eutrophication gradient in the northern Everglades after ∼80 % reduction in inflow P loads and inflow P concentrations now reduced to 10–18 μg/L. The new Everglades Water Quality Recovery Model (EWQRM) is parsimonious, process-informed, simulates longitudinal internal P profiles at annual scale, and operates in two modes. In ‘idling mode’, the model approximates annual average profiles in internal P loading rates (iPLR) using P samples collected under no-flow conditions (following recent developments). In ‘operational’ mode, it calibrates P settling rates (k-values) to P profiles measured under flows based on inflow rates, concentrations and the estimated iPLR gradients (R² = 0.6–0.9). Internal load estimates (from idling mode) indicated gradually decreasing return fluxes in severely impacted inflow regions from ∼3 g/m²-yr in the late 1990's to &lt;0.5 in recent years. Calibrated settling rates (from operational mode) showed strong correlation with hydraulic loading rates (R² = 0.83). There was no apparent ‘leaking’ of elevated water P from impacted to downstream ‘native’ regions over time. However, there is an increasingly clear signature of internal P loading on marsh P concentrations in already impacted regions as inflow P loads decreased over time. Projections indicate a + 25-year timeframe for continued relaxation of iPLR to achieve 10 μg/L water P levels in impacted regions, resulting in a net recovery timeframe to near-native water quality of ∼50 years after input reductions.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107880"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837119","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":"Effects of typical ecological drainage ditches on nitrogen reduction under different slope conditions","authors":"Weili Duan ,&nbsp;Yuguo Han ,&nbsp;Yunfei Tan ,&nbsp;Senpei Xiao ,&nbsp;Jinbao Shao","doi":"10.1016/j.ecoleng.2025.107888","DOIUrl":"10.1016/j.ecoleng.2025.107888","url":null,"abstract":"<div><div>Ecological drainage ditches function not only as conduits for surface runoff but also as effective measures for reducing nutrient loads, particularly nitrogen and phosphorus, and are therefore widely applied in mitigating agricultural non-point source pollution. Slope is a critical factor influencing nitrogen removal, as it regulates flow velocity and hydraulic retention time, both of which govern nutrient transport and biogeochemical reaction. Despite this importance, the effects of slope on nitrogen removal performance in drainage ditches remain insufficiently investigated. In this study, three types of ecological drainage ditches—concrete-pier porous-brick (ED1), vegetated porous-brick (ED2), and sod-lined gravel–sand–soil ditches (ED3)—were evaluated, with a conventional concrete ditch (CD) serving as a control. Field scouring experiments were conducted under three slope gradients (1°, 5°, and 9°), representing gentle, moderate, and steep conditions, with two flow rates (70 and 140 L·min⁻¹) applied to assess nitrogen removal efficiency under different hydraulic regimes. Results showed that slope markedly affected TN removal efficiency, with distinct responses across ditch types. ED2 was the most sensitive to slope changes, with its TN removal efficiency decreasing by 15.8 % as slope increased from 1° to 9°. In comparison, TN removal efficiency declined by 14.0 % in ED3 and by only 3.7 % in ED1. Notably, ED3 maintained relatively stable TN removal efficiency across slope gradients while sustaining a high overall level of removal. Functional priorities of ditches varied with slope conditions: gentle slopes favored nutrient removal, moderate slopes necessitated a balance between water conveyance and nutrient removal, and steep slopes emphasized water conveyance supplemented by localized ecological interventions. These findings underscore the importance of aligning ditch types with slope conditions, thereby optimizing ecological engineering strategies for agricultural non-point source pollution control and improving regional water quality to support agricultural sustainability.</div></div>","PeriodicalId":11490,"journal":{"name":"Ecological Engineering","volume":"224 ","pages":"Article 107888"},"PeriodicalIF":4.1,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837194","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}