Water Regulation Research Articles

The daily minimum leaf turgor pressure can represent the water status of apple trees under drip irrigation

IntroductionAccurate diagnosis of the water status of fruit trees is a prerequisite for precise irrigation. Measurement of leaf turgor pressure provides a means to explore the water utilization mechanisms of fruit trees and their responses to water stress. However, there are few studies on the use of daily minimum leaf turgor pressure (Ppmax) to indicate water information in apple tree.MethodsWe monitored Ppmax, stem flow rate (Vstem), leaf water potential, soil water, and the main meteorological factors under two drip irrigation levels (fully irrigated and under-irrigated) to elucidate the temporal dynamics of the daily leaf turgor minimum of apple trees and diagnose the water status of fruit trees.ResultsThe results showed that soil water deficiency could reduce leaf turgor pressure and increase Ppmax. In both years, the signal intensity and sensitivity of Ppmax were better than those of Vstem, and the sensitivity was 3.31 and 2.94 times of Vstem, respectively. Compared to Ppmax, Vstem had a higher correlation with meteorological factors and was more affected by meteorological conditions, independent of irrigation treatment. Ppmax was significantly negatively correlated with soil and leaf water potential, and its correlation coefficient was 2.58–4.89 times higher than that between Vstem and both.DiscussionThese results not only enhance our understanding of the water regulation strategies employed by apple trees under drought conditions but also provide a theoretical foundation for developing efficient water-saving practices and precision irrigation strategies for fruit trees.

A Case Study on Recycling Industrial Wastewater with Nanofiltration Membrane Separation Technology

As pressure on water resources intensifies and stringent regulations for groundwater and surface water are enacted, wastewater recycling has emerged as a key research objective for many enterprises. In this study, based on the actual wastewater discharged from Eternal Electronic (Suzhou, China) Co., Ltd., the performance differences in different membrane materials in treating this wastewater were analyzed and compared. The NF90 membrane was ultimately selected as the most suitable choice for treating this wastewater with optimal operating conditions of 150 psi, 25 °C, and 1 L/min, respectively. All the indices of wastewater treatment can satisfy the standard of circulating cooling water. In addition, this work is closely combined with the practical applications by using an HCl solution (pH = 3–4) to clean the fouled membranes, thus effectively solving the membrane fouling in the treatment process. This approach not only satisfies the environmental management requirements of enterprises but also provides valuable insights for similar wastewater treatment projects.

Hydroponic System with Integrator Modified on PI Controller for Nutrient and Water Regulation

— This study developed a hydroponic control system to regulate nutrient concentration (PPM) and water volume using a Proportional-Integral (PI) controller. The PI controller was chosen for its simplicity and effectiveness in systems that do not require fast response times. A trial-and-error method was used to tune the Kp and Ki values, which were implemented in an ATMega328 microcontroller. The system consists of one AC pump and two DC pumps: DC Pump-1 controls the PPM by supplying liquid fertilizer, while DC Pump-2 regulates the water volume. The results showed that modifying the PI controller with an integrator limitation improved performance. For PPM control, a limit of 13000 with Kp = 2 and Ki = 0.01 resulted in a 0.5% error, 56.8-second rise time, and a 4.8% overshot. For water level control, a limit of 12000 with Kp = 100 and Ki = 0.16 yielded a 3.25% error, 2% overshot, and a 65.4-second rise time. The test results demonstrated that the use of AB Mix can be reduced by up to 26% compared to a conventional PID, with an initial PPM value of around 350.

Multiscale Effects of Xylella fastidiosa on Landscape Services

The spread of Xylella fastidiosa since 2013 in the Mediterranean olive groves of the Apulia region has modified the landscape. The aims of this research are focused on the analysis of its effects on the following: (1) Landscape multifunctionality supported by olive groves in terms of landscape service provision; (2) The functional relations among the main Mediterranean land covers in terms of landscape service supply and demand. (3) The landscape fragmentation at different spatial scales. The landscape has completely changed, mainly in those land covers that, in the past, acted as stabilizing factors (croplands and olive groves), which has been replaced by grasslands in 2021. The main effects of Xylella fastidiosa were on the multifunctionality of olive grove landscape in terms of food production, water regulation, carbon sequestration, and pollination, as well as on landscape cultural value. Ecosystem service supply is mainly related to olive groves, tree covers, shrublands, and wetlands. The province of Lecce showed the highest fragmentation, as demonstrated by the number of patches, the mean patch area, and the DIVISION metric, while the province of Brindisi was the least fragmented, with a DIVISION metric similar in 2011 and in 2021. The multiscale assessment of “olive groves” fragmentation has helped in better analyzing the effect of its spatial configuration on the provision of landscape services and in identifying the right spatial scale for each landscape service provision. It is essential to analyze landscape service flow to enlarge the understanding of the ways in which their supply is maintained through a landscape regeneration policy toward the socio-economic–ecological recovery.

Deciphering the grain size fining and provenance variation of lower Yellow River fluvial sediments in light of Holocene climatic changes and anthropogenic influences

The dynamics of fluvial processes in the lower Yellow River during the warm Early and Middle Holocene can serve as an analogue for future global warming, thus providing a scientific basis for addressing contemporary river issues. However, the Early and Middle Holocene riverbed sediments in the lower Yellow River have rarely been investigated. Here, we conducted detrital zircon UPb dating and grain-size analysis of four riverbed samples with different ages collected via four boreholes across the North China Plain. Our results revealed that during the Early Holocene, coarse-grained sediments derived from upstream mountains were widely present as a result of gradually increasing precipitation. During the Middle Holocene, riverbed sediments gradually became finer due to the increased input of fine-grained sediments from the Chinese Loess Plateau following the northward shift of the rain belt. During the Late Holocene, riverbed sands continued the fining trend because of reduced stream flow, which limited the transport of coarse-grained sediments into the lower reaches. Continuous enhanced anthropogenic influences resulted in more fine-grained sediments in the riverbed. We conclude that millennial-scale precipitation variation controlled the flow discharge and sediment composition in the lower Yellow River during the Holocene. Our findings suggest that increasing flow discharge through water regulation can effectively address current challenges and help adapt to future global warming.

The Response of Runoff to Land Use Change in the Northeastern Black Soil Region, China

With the intensification of climate change and human activities, the impacts of land use shifts on hydrological processes are becoming more pronounced, especially in regions with complex geographic, geological, and climatic conditions such as the Northeast Black Soil Region, China. This study quantitatively examines the variations in various land use types from 1980 to 2020 by means of a land use transfer matrix, and it incorporates the multi-year average runoff value to mitigate the interference of short-term climate fluctuations on the runoff trend, thereby enhancing the representativeness and stability of the simulation outcomes. The SWAT (Soil and Water Assessment Tool) model is employed to simulate land use alterations in different periods. The findings indicate that the area of farmland increased by 5.34% and the area of grassland decreased by 5.36% over 40 years. The areas of forest land and wetland have fluctuated significantly due to policy interventions and population growth. This study discovers that LUCC has resulted in a marginal increase in annual water yield. For instance, the water yield of paddy fields in 2020 amounts to 92.26 mm/year, which is 0.52–9.42% higher than the historical scenario and exhibits a notable upward trend in summer. Spatial analysis discloses regional disparities, with substantial changes in the hydrological behavior of northern watersheds (such as the Huma River) and southeastern regions (such as the Toudao River). The augmentation of wetland and forest coverage has effectively mitigated peak runoff, especially during extreme rainfall events. Wetlands have manifested strong water regulation capabilities and alleviated the impact of floods. This study quantitatively discloses the complex response pattern of LUCC to runoff by introducing a multi-scale analysis approach, which furnishes a scientific basis for flood risk assessment, land use optimization, and water resource management, and demonstrates the potential for extensive application in other countries and regions with similar climatic and topographic conditions.

Understanding water-energy-carbon nexus in English and Welsh water industry by assessing eco-productivity of water companies

Understanding the water-energy-carbon nexus in water supply is essential for water regulators and utilities. This study employs a non-radial Data Envelopment Analysis (DEA) model to assess eco-productivity (ecoP) change, a synthetic indicator that integrates carbon emissions, energy costs, and water delivered. It also evaluates its components—eco-efficiency change and eco-technological change—across water companies in England and Wales from 2011 to 2018. The analysis reveals an annual improvement in ecoP of 1.1%, driven by a 2.1% gain in eco-efficiency but offset by a 1.0% decline in technological advancement. The reduction in GHG emissions emerged as the most significant positive contributor, enhancing ecoP by 3.22% annually, while energy costs detracted ecoP by –0.09%. The results underscore the negative impacts of increased water delivery (–1.74%) and the number of connected properties (–1.27%) on ecoP, highlighting the need for demand management policies.

Study on the effects of extreme climate and human activities on the growth mechanisms of Zostera japonica in the Yellow River estuary

Zostera japonica, as one of the major seagrasses in the Yellow River Estuary, plays a critical ecological role, particularly in providing habitat for marine organisms, stabilizing sediment, and contributing significantly to carbon sequestration. In recent years, Zostera japonica seagrass beds have receded extensively due to multiple impacts of natural factors and human activities. This study investigates the complex effects of extreme climate events and human activities on the growth mechanisms of Zostera japonica in the Yellow River Estuary using a combination of field sampling, laboratory analysis, and quantitative calculations. The result shows that there are significant differences in sediment characteristics between the north and south shores, with the south shore having finer sediments and higher nutrient content, which support more robust seagrass growth. The Water and Sediment Regulation Scheme (WSRS) dramatically alters water quality by reducing salinity and increasing turbidity, thus inhibiting photosynthesis and disrupting the physiological functions of Zostera japonica. Additionally, WSRS introduces an increase in heavy metals, which could potentially impact plant health and stress levels. Extreme weather events, particularly Super Typhoon Lekima, further compound these impacts by causing soil erosion, uprooting seagrass beds, and reducing biomass and seed production. The interplay of WSRS, climate change, and anthropogenic activities necessitates integrated management strategies to mitigate adverse effects and enhance habitat resilience. This study underscores the need for specific management strategies, such as controlling heavy metal inflows, implementing sediment stabilization techniques, and regulating freshwater discharge during key growth periods, to mitigate adverse effects and enhance habitat resilience for Zostera japonica in the Yellow River Estuary.

Transformer-Based hyperspectral image analysis for phenotyping drought tolerance in blueberries

Drought-induced stress significantly impacted blueberry production due to the plants’ inefficient water regulation mechanisms to maintain yield and fruit quality under drought stress. Traditional methods of manual phenotyping for drought stress are not only time-consuming but also labor-intensive. To address the need for accurate and large-scale assessment of drought tolerance, we developed a high-throughput phenotyping (HTP) system to capture hyperspectral images of blueberry plants under drought conditions. A novel transformer-based model, LWC-former was introduced to predict leaf water content (LWC) utilizing spectral reflectance from hyperspectral images obtained from the developed HTP system. The LWC-former transformed the spectral reflectance into patch representations and embedded these patches into a lower dimensional to address multicollinearity issues. These patches were then passed to the transformer encoder to learn distributed features, followed by a regression head to predict LWC. To train the model, spectral reflectance data were extracted from hyperspectral images and pre-processed using log(1/R), mean scatter correction (MSC), and mean centering (MC). The results showed that our model achieved a coefficient of determination (R2) of 0.81 on the test dataset. The performance of the proposed model was also compared with TabTransformer, DeepRWC, multilayer perceptron (MLP), partial least squares regression (PLSR), support vector regression (SVR), and random forest (RF), achieving R2 values of 0.65, 0.73, 0.71, 0.47, and 0.58, respectively. The results demonstrated that LWC-former outperformed other deep learning and statistical-based models. The high-throughput phenotyping system effectively facilitated large-scale data collection, while the LWC-former model addressed multicollinearity issues, significantly improving the prediction of LWC. These results demonstrate the potential of our approach for large-scale drought tolerance assessment in blueberries.

Water and chloride as allosteric inhibitors in WNK kinase osmosensing.

Osmotic stress and chloride regulate the autophosphorylation and activity of the WNK1 and WNK3 kinase domains. The kinase domain of unphosphorylated WNK1 (uWNK1) is an asymmetric dimer possessing water molecules conserved in multiple uWNK1 crystal structures. Conserved waters are present in two networks, referred to here as conserved water networks 1 and 2 (CWN1 and CWN2). Here, we show that PEG400 applied to crystals of dimeric uWNK1 induces de-dimerization. Both the WNK1 the water networks and the chloride-binding site are disrupted by PEG400. CWN1 is surrounded by a cluster of pan-WNK-conserved charged residues. Here, we mutagenized these charges in WNK3, a highly active WNK isoform kinase domain, and WNK1, the isoform best studied crystallographically. Mutation of E314 in the Activation Loop of WNK3 (WNK3/E314Q and WNK3/E314A, and the homologous WNK1/E388A) enhanced the rate of autophosphorylation, and reduced chloride sensitivity. Other WNK3 mutants reduced the rate of autophosphorylation activity coupled with greater chloride sensitivity than wild-type. The water and chloride regulation thus appear linked. The lower activity of some mutants may reflect effects on catalysis. Crystallography showed that activating mutants introduced conformational changes in similar parts of the structure to those induced by PEG400. WNK activating mutations and crystallography support a role for CWN1 in WNK inhibition consistent with water functioning as an allosteric ligand.

Water and chloride as allosteric inhibitors in WNK kinase osmosensing

Osmotic stress and chloride regulate the autophosphorylation and activity of the WNK1 and WNK3 kinase domains. The kinase domain of unphosphorylated WNK1 (uWNK1) is an asymmetric dimer possessing water molecules conserved in multiple uWNK1 crystal structures. Conserved waters are present in two networks, referred to here as conserved water networks 1 and 2 (CWN1 and CWN2). Here, we show that PEG400 applied to crystals of dimeric uWNK1 induces de-dimerization. Both the WNK1 the water networks and the chloride-binding site are disrupted by PEG400. CWN1 is surrounded by a cluster of pan-WNK-conserved charged residues. Here, we mutagenized these charges in WNK3, a highly active WNK isoform kinase domain, and WNK1, the isoform best studied crystallographically. Mutation of E314 in the Activation Loop of WNK3 (WNK3/E314Q and WNK3/E314A, and the homologous WNK1/E388A) enhanced the rate of autophosphorylation, and reduced chloride sensitivity. Other WNK3 mutants reduced the rate of autophosphorylation activity coupled with greater chloride sensitivity than wild-type. The water and chloride regulation thus appear linked. The lower activity of some mutants may reflect effects on catalysis. Crystallography showed that activating mutants introduced conformational changes in similar parts of the structure to those induced by PEG400. WNK activating mutations and crystallography support a role for CWN1 in WNK inhibition consistent with water functioning as an allosteric ligand.

Cropland functional diversity increases ecosystem services supply in watersheds of the Rio de la Plata Grasslands

ContextImplementing heterogeneous rural landscapes with high agricultural diversity and a substantial proportion of natural habitats has been proposed to ensure food production while reducing negative impacts on ecosystem services. However, evidence of an increased supply of ecosystem services (ES) in more heterogeneous landscapes remains limited, with no consensus.ObjectivesTo evaluate the effect of the spatial cropland system’s diversity and landscape configuration on indicators of the supply of ES in agricultural landscapes of the Rio de la Plata Grasslands region.MethodsWe analyzed the relationship between indicators of ES supply and the heterogeneity of 1121 microwatersheds. We assessed the Ecosystem Services Supply Index (ESSI), the Hydrological Yield (HY), and the Absorbed Photosynthetically Active Radiation (APAR) in agricultural areas. We calculated the average grassland patch area, the structural and functional cropland diversity, the cropland percentage, and the grasslands’ juxtaposition to assess landscape heterogeneity.ResultsMicrowatersheds with higher cropland functional diversity showed higher values for indicators of ES supply. They were positively related to the ESSI and APAR, and negatively with HY, indicating positive effects on Carbon gains and water regulation processes. In contrast, grasslands’ juxtaposition had opposite effects to those of cropland functional diversity, so the spatial segregation of grasslands favored the ES supply.ConclusionsFunctional cropland diversification and the segregation of natural grasslands improved proxies of ES and counteracted the negative effects of cropland amount. These findings contribute to the design of multifunctional landscapes and suggest that cropland functional diversity and grassland configuration should be considered in food production systems aimed at preserving ES supply.

Advancements in maize cultivation: synergistic effects of dry atmospheric plasma combined with plasma-activated water

Abstract In this study, we investigate the effects of pre-germinative and post-germinative plasma treatments, applied separately or in combination, to improve maize germination and early seedling development. Pre-germinative treatment consists of priming the seeds with a dry atmospheric plasma (DAP) generated by a dielectric barrier device, characterized by minimal radiative emission, low electrical power (4 W) and high emissions of O, OH and NO radicals. Post-germinative treatment, known as plasma-activated water (PAW), uses a single pin electrode device (SPED) to generate a DC discharge that features a power of 126 W and produces large amounts of OH radicals. The resulting PAW, after 5 min of SPED treatment, induces a slight acidification and increased concentrations of nitrate ions (from 24 to 250 mg l−1), nitrite ions (from less than 0.1 to 56.1 mg l−1) and hydrogen peroxide (from 0.3 to 18.5 mg l−1). Results indicate that DAP applied on maize seeds for 20 min boosts their germination rate by up to 90% (versus only 65% for untreated seeds) while reducing the median germination time by 37.5%. Then, seedling growth monitoring is achieved on control, DAP, PAW and DAP + PAW groups to assess stem length, hypocotyl length, leaf count, collar diameter and fresh/dry mass. The DAP + PAW group shows the most robust growth, demonstrating a synergistic effect of the combined treatments, particularly with significantly longer stem lengths. Additionally, physiological analyses of seedling leaves indicate a decrease in chlorophyll content despite enhanced growth, while fluorescence microscopy reveals a reduction in stomatal density in leaves treated with DAP and PAW, especially in the combined treatment group, potentially impacting photosynthetic efficiency and water regulation.

Molecular Mechanisms of Poplar Adaptation to Water–Fertilizer Coupling: Insights from Transcriptomic and Metabolomic Analyses

The aim of this paper was to investigate the transcriptomic and metabolomic differences in Populus cathayana × canadasis ‘Xinlin1’ (P. cathayana × canadasis ‘Xinlin 1’) under varying irrigation and fertilization conditions. Ten-year-old P. cathayana × canadasis ‘Xinlin 1’ was selected as the test subject in this study; different irrigation and fertilization treatments were set up, and DEGs and DAMs in response to water and fertilizer regulation were identified. Transcriptomic and metabolomic profiles were analyzed from both leaves and roots. A total of 22,870 DEGs were identified in response to water and fertilizer treatments, predominantly belonging to 48 transcription factor families, including MYB, ERF, and MYB-related ones. Additionally, 2432 DAMs were detected and categorized into 18 metabolite classes, with flavonoids being the most abundant (342 metabolites), followed by terpenoids, lipids, and others. KEGG enrichment analysis revealed that DEGs and DAMs were significantly associated with pathways such as plant hormone signal transduction and starch and sucrose metabolism pathways. The levels of ABA exhibited an initial decrease followed by an increase, with several key genes, including PYR/PYL, PP2C, SnRK2, and ABF, also differentially expressed in the plant hormone signal transduction pathway. In the starch and sucrose metabolic pathways, sucrose was more hydrolyzed into D-fructose, which gradually translocated from roots to leaves. DEGs were significantly involved in sucrose synthesis and decomposition into D-fructose and 1,3-β-glucose, as well as starch synthesis and starch decomposition into cellulose dextrin, which underwent complete hydrolysis to glucose. In the starch hydrolysis process, 29 DEGs were involved, with 12 down-regulated and 17 up-regulated.

Water-Driven Stacking Structure Transformation of Ultrathin Ru Nanosheets for Efficient Hydrogen Evolution Reaction.

Ultrathin crystalline materials are a class of popular materials that can potentially exhibit fascinating physical and chemical properties dictated by their unique stacking freedom. However, it is challenging to achieve the controllable synthesis over their stacking structure for ultrathin crystalline materials. Herein, water is employed as a key regulatory factor to realize phase engineering in ultrathin nanosheets (NSs), thereby altering stacking faults to achieve distinct stacking arrangements. Ruthenium (Ru) NSs with consistent specific surface areas but different stacking manners are fabricated through the systematic regulation of water. Based on this, it is demonstrated that the hydrogen evolution reaction (HER) performance can be significantly influenced by their stacking structures. Further in-depth investigations reveal that the distinct stacking structures of Ru NSs, featuring a limited area of side facets, will influence the energy barrier of sluggish Volmer step in HER. Ru NSs with ABC stacking exhibit an accelerated Volmer process with outstanding catalytic activity, demonstrating a remarkably low overpotential (25mV at 10mAcm-2) and Tafel slope (29mVdec-1) than most of the reported HER catalysts. The work will advance the understanding of controllable synthesis methods and illuminate the structure-activity relationships in ultrathin crystalline nanomaterials.

Impact of land use/land cover (LU/LC) changes on ecosystem service values in Muger Sub-basin, Upper Blue Nile Basin, Ethiopia

This study was conducted to estimate the impact of land use/land cover (LULC) changes on the ecosystem service value (ESV) in the Upper Blue Nile basin over three-decade (1986–2020). The findings revealed that there is a decline in total ESV from US$ 492.77 × 106 in 1986 to US$ 400.65 × 106 for the year 2020. The ESV lost between 1986 and 2020 was about US$ 92.11 × 106. In terms of the individual ecosystem services, the contribution of all service values declined except food production and biological control. Among the major contributors of ESVs, food production, water regulation, erosion control, climate regulation, nutrient cycling, waste treatment, and water supply represent 89%, 88%, 86% in 1986, 2003, and 2020, respectively. Soil erosion and sediment transport under environmental pressure significantly contributed for the loss of ecosystem services (ES) in the sub-basin. In addition, FGD and KII ranked provisioning ecosystem services first in order of importance for communities in the study area. Therefore, it is important to pay attention to the sustainable conservation and restoration of natural resources through natural vegetation protection, enhanced vegetation cover, conservation practices and wetland management to enhance the natural capital and ecosystem services in the Muger Sub-basin.

Equitable access to drinking-water: focus on European Union member states

ABSTRACT The European Union's (EU) 2020 Drinking Water Directive (DWD) requires member states to advance equitable access to drinking-water and to promote tap water. Although access to drinking-water is high in most EU member states, disparities still exist, for example, among vulnerable and marginalized groups such as the homeless, Roma, and traveller groups. To analyze challenges and measures taken in high-income EU member states, we reviewed national reports from the UNECE/WHO Protocol on Water and Health and conducted a survey and interviews among water regulators. Reported barriers include insufficient data, a lack of mechanisms to identify vulnerable and marginalized groups, a lack of investment in rural areas, affordability concerns, and limited coordination between institutions. Measures comprise improving data on access by vulnerable and marginalized groups, introducing or revising social tariffs, and directing funding to rural areas. As the barriers are crosscutting, the involvement of all relevant institutions is crucial, and coordination and cooperation between the national and local level is indispensable. The DWD creates momentum for progressing equitable access in the EU and is expected to foster evidence-based government actions to improve equitable access to drinking-water.

Biophysical factors affecting transpiration of typical afforestation species under environmental change in the Loess Plateau, China

Transpiration in artificial forests has a vital role in the ecohydrological cycle and evolution of afforestation in semi-arid regions. However, further research is required to understand the impacts of biotic and abiotic factors on transpiration and water regulation strategies in tree species under climate change. We used the sap flow method to quantify transpiration in three adjacent plantations (Pinus tabuliformis, Populus simonii, and Ulmus pumila) spaced 40 m apart, and concurrently monitored soil moisture and meteorological variables. Significant differences in average transpiration were observed in the following order: P. simonii (1.31 ± 0.49 mm d–1) > U. pumila (1.04 ± 0.45 mm d–1) > P. tabuliformis (0.75 ± 0.31 mm d–1), due to differences in the canopy conductance, which followed the order of P. simonii (2.02 ± 0.18 mm/s) > U. pumila (1.70 ± 0.15 mm/s) > P. tabuliformis (1.26 ± 0.11 mm/s) (P < 0.05). Under severe soil water stress, high vapor pressure deficit, and high solar radiation, transpiration was reduced in all species during the drought period in 2022 because of reduced canopy conductance (P < 0.05). Our findings demonstrate that a fast growth rate, deep root systems, and close relationships between the leaf water potential and stomatal regulation are vital strategies for trees responding to drought. Consequently, we recommend P. simonii for shelter forests and P. tabuliformis for ecological landscape forests to improve the stability of afforestation in semi-arid regions.

Flood regulation ecosystem services analysis and security pattern optimization for resilient management adapted to the complex terrain of coastal estuaries: A case study in Xiamen

The flood risk in coastal areas has been exacerbated by global climate change. Research on flood risk assessment is emerging from the perspective of supply and demand for flood regulation ecosystem services (FRES). However, there are still limitations in the evaluation of lowland regulation, implementation of intelligent algorithms, comparison of multi-grain FRES supply and demand, and overall optimization of security pattern. Therefore, we propose a comprehensive FRES supply assessment method that incorporates soil and vegetation, lowland, and water regulations. Additionally, we introduce the random forest model to enhance the FRES demand assessment approach. Two grain sizes of the sub-catchment area and grid unit are used to compare FRES supply and demand. Using Xiamen as a case study, this research unveils the following findings: (1) Significant disparities exist between the assessment outcomes of FRES based on multiple types of regulatory services and those solely considering soil and vegetation regulation. The areas with high FRES supply extend beyond upper mountain forests to include local lower plains exhibiting strong capabilities for lowland or water system regulation. (2) Consistent yet distinct results are observed when comparing two grain sizes. Imbalances in supply and demand occur in estuaries, bays, and densely built-up regions. Sub-catchment units exhibit wider distribution and concentration, while grid units display more dispersed patterns. (3) In terms of in-situ regulation, 26.77 km2 ecological protection area, 9.85 km2 ecological restoration area, and 119.59 km2 construction land flood control intervention area are demarcated. From a directional regulation perspective, 22 FRES corridors connecting source and sink areas along with 24 pinch points are identified. Optimizing security patterns through coordinated management of FRES supply and demand can enhance the resilience of coastal estuaries.

Assessment of the extent of community preparedness to flood risk in Jigawa State, Nigeria

Jigawa State faces annual flood disasters that have resulted in significant loss of life and property, putting many communities at risk. This study aim to evaluate the preparedness for flood risk in Jigawa State, Nigeria. A sample of 666 respondents was selected for a self-administered questionnaire, with 601 fully completed. The collected data were analyzed descriptively to determine the preparedness index. (PI). From the result of the findings, a majority (77.7%) of the respondents agreed that the community is aware of flood risks. There was also a provision of a neighborhood directory (97.8%), local shelter (75.9%) and emergency contacts (55.4%) during floods. The PI (92.6%, 98.6% 84.1% and 85.1% respectively), are above the 65% threshold and hence considered ‘prepared’ in this regard; but, ‘somewhat prepared’ (PI of 61.7%) regarding awareness of flood disaster risk management strategies; ‘and unprepared’ (PI of 55.5%, 50.5%, 50.5%, 50.8% and 54.3% respectively) in terms of community organization of public education and training of flood risk reduction (66.6%); engagement on rehearsals/emergency drills (51.6%); good community-based warning system (51.4%); and a standalone system for property protection measures during floods (52.4%); as well as an active recovery plan (62.9%). It was recommended that proper embankment protection and water regulation outlets be established. Additionally, real-time flood forecasting and effective early warning systems should be developed. Communities should be assessed to identify flood risk zones before construction activities begin, or alternatively, resettlement to safer areas should be considered for those living in flood-prone regions.