Low Inundation Research Articles

Integrating field surveys and remote sensing to optimize phosphorus resource management for rainfed rice production in the Central plateau of Burkina Faso.

Rice production in sub-Saharan Africa (SSA) is restricted by low water availability, soil fertility, and fertilizer input, and phosphate rock (PR) application is expected to increase production. Soil water conditions and soil types affect the efficacy of phosphorus fertilization in improving productivity. However, these factors are rarely discussed together. In this study, we aimed to investigate the soil types and soil water conditions in the fields, as well as their effects on rice productivity after phosphorus fertilization, and optimize the findings using remote sensing techniques. A soil profiling survey, followed by a field experiment in seven farmer fields, was performed in the Central plateau of Burkina Faso. The following treatments were applied: nitrogen and potassium fertilization without phosphorus (NK), PR application with NK (NK+PR), and triple super phosphate (TSP) application with NK (NK+TSP). Submergence duration and cumulative water depth were recorded manually. The inundation score, estimated using a digital elevation model, explained the distribution of soil types and soil water conditions and correlated negatively with sand content and positively with silt and clay content, indicating an illuvial accumulation of fine soil particles with nutrient transportation. The field experiment showed that although grain yield was significantly restricted by phosphorus deficiency, the increase in yield after phosphorus fertilization was higher in Lixisols and Luvisols than in Cambisols because of the low Bray-2-phosphorus content of Lixisols and Luvisols. The inundation score correlated positively with grain yields after NK+PR and NK+TSP treatments. In conclusion, soils with low inundation scores (mainly Lixisols and Luvisols) showed a drastic increase in grain yield after TSP application, whereas those with high inundation scores showed comparable yields after PR and TSP application despite the low phosphorus fertilization effect. Our findings would help optimize fertilization practices to increase rice productivity in SSA.

Interactions between vegetation, sedimentation and flood inundation levels in wetlands

Wetlands produce key ecosystem services to mitigate the impacts of peak flows caused by pluvial or fluvial floods or storm surges. Sediment floods were characterized by a peak flow flowing over a simulated wetland, populated with two natural species. Floods have been drawn as flows of height H, into waters of height h, where H > h. Peak flow along the flume passed through: peak flow adjustment; peak flow; drag-dominated peak flow; and gravity current regimes. For high inundation wetland levels, settling rates of coarse and fine sediment were similar during the peak flow regime. At larger distances, sedimentation decreased monotonically, with higher sedimentation of fine particles. For low inundation levels, the sedimentation rate during the drag-dominated peak flow regime was higher for coarse particles. Vegetation decreased the inundation level needed for enhancing sedimentation. Our study then adds practical knowledge at considering that the synergies between the vegetation and the inundation level may enhance wetland services such as the mitigation of pluvial, fluvial or coastal floodings.

Higher apical meristem in tall fescue as adaptation strategy to recurring short‐term inundation

AbstractSoil inundation frequency and intensity in the central United States are predicted to increase because of climate change. Soil inundation is expected to negatively affect plant growth and persistency. Our objective was to measure tiller and apical meristem height, leaf area index (LAI), and leaf‐to‐stem ratio effects on tall fescue (Schedonorus arundinaceus (Schreb.)) under different levels of soil inundation intensity. The study was conducted on a commercial farm in northwestern Ohio, from spring to fall 2021. Three different levels of inundation were observed and assigned as treatments: no inundation, low inundation (LI), and high inundation (HI). LI and HI were defined by the duration on which the soil was inundated after heavy rain events: 1–2 and 3–5 days after rain, respectively. Meristem and tiller height were higher during spring (p < 0.001), and lower in late summer across treatments (p < 0.001). The higher LAI and leaf‐to‐stem ratio occurred in spring, probably due to higher leaf mass (p < 0.001). As seasons progressed, plant and meristem height, LAI, and leaf mass decreased (p < 0.001). Despite not being considered an inundation‐tolerant species, tall fescue showed morphological adaptation to the inundation levels of our study, suggesting that this species can be used to manage fields prone to short‐term inundation.

The zoning of flood disasters by combining tidal flood and urban flood in Semarang City, Indonesia

Semarang City, situated along the northern coastal region of Java Island, Indonesia, grapples annually with the dual challenges of tidal flooding and urban inundation. Establishing a comprehensive flood disaster zoning for both tidal floods and urban inundation to identify priority areas for effective flood mitigation and reducing disaster risk. This study aims to assess the potential inundation of tidal floods, urban floods, and their combined impact on Semarang City, using an integrated approach that combines Geographic Information System (GIS) technology with the Analytic Hierarchy Process (AHP). By leveraging data from Digital Elevation Model Nasional (DEMNAS), Google Earth, Rupa Bumi Indonesia (RBI) maps, and the Open Street Map (OSM) database, we obtained elevation, landcover, distance to the river, buildings, and administration data, which were used as criteria in the analysis. The research findings unveil three distinct flood inundation scenarios within Semarang City: tidal floods, urban floods, and a combination of both. Each scenario is categorized into low, medium, and high levels of inundation, providing a granular assessment of flood risk across the city. Importantly, the study extends beyond spatial analysis to evaluate the impact of inundation on affected buildings. The results indicate that the area inundated by the combination of tidal and urban floods is as follows: 86.87% high inundation, 13.12% moderate inundation, and 0.01% low inundation.

A study of climate resilience in urban tree species of Peninsular Malaysia

<p>Climate change poses significant challenges to Malaysian cities, including heat stress, which high humidity and the urban heat island effect exacerbate. While trees effectively reduce temperatures and improve microclimates, potential sensitivities to climate change impacts require careful species selection. Experts assessed the resilience of 220 tree species from urban and rural areas of Malaysia using eight criteria, based on a list compiled from four sources. We then categorised the species by sensitivity for four urban landscape types. Saltwater sensitivity had the highest proportion of sensitive species, followed by inundation sensitivity. Considering regional climate projections, planners should prioritise species with low inundation sensitivity. Data availability for saltwater, inundation, and high-temperature sensitivities was limited but adequate for the remaining criteria, with susceptibility to predation, parasitism, or disease, and sensitivity to storm conditions being of concern. Urban planners should integrate these criteria into decision-making to ensure climate-smart urban design. Given that our knowledge about the effects of climate change on tree species will advance and should be documented, we developed an open-collaborative online database that assists stakeholders in selecting suitable species for various sites in Malaysia. Moderators will review submissions to ensure consistent application of criteria and alignment between selected answers and supporting information. Assessors can contribute to quality control by voting for assessments they agree with. Our research emphasises the importance of proactively addressing climate change challenges in urban areas and underscores the value of informed decision-making to enhance the resilience of urban tree populations.</p>

Flood economic vulnerability and risk assessment at the urban mesoscale based on land use: A case study in Changsha, China

With climate change and urbanization, flood disasters have significantly affected urban development worldwide. In this study, we developed a paradigm to assess flood economic vulnerability and risk at the urban mesoscale, focusing on urban land use. A hydrological simulation was used to evaluate flood hazards through inundation analyses, and a hazard-vulnerability matrix was applied to assess flood risk, enhancing the economic vulnerability assessment by quantifying the differing economic value and flood losses associated with different land types. The case study of Wangchengpo, Changsha, China, found average total economic losses of 126.94 USD/m2, with the highest risk in the settlement core. Residential areas had the highest flood hazard, vulnerability, and losses (61.10% of the total loss); transportation areas accounted for 27.87% of the total economic losses due to their high flooding depth. Despite low inundation, industrial land showed greater economic vulnerability due to higher overall economic value (10.52% of the total). Our findings highlight the influence of land types and industry differences on flood vulnerability and the effectiveness of land-use inclusion in urban-mesoscale analyses of spatial flood characteristics. We identify critical areas with hazard and economic vulnerability for urban land and disaster prevention management and planning, helping to offer targeted flood control strategies to enhance urban resilience.

A study of climate resilience in urban tree species of Peninsular Malaysia

<p>Climate change poses significant challenges to Malaysian cities, including heat stress, which high humidity and the urban heat island effect exacerbate. While trees effectively reduce temperatures and improve microclimates, potential sensitivities to climate change impacts require careful species selection. Experts assessed the resilience of 220 tree species from urban and rural areas of Malaysia using eight criteria, based on a list compiled from four sources. We then categorised the species by sensitivity for four urban landscape types. Saltwater sensitivity had the highest proportion of sensitive species, followed by inundation sensitivity. Considering regional climate projections, planners should prioritise species with low inundation sensitivity. Data availability for saltwater, inundation, and high-temperature sensitivities was limited but adequate for the remaining criteria, with susceptibility to predation, parasitism, or disease, and sensitivity to storm conditions being of concern. Urban planners should integrate these criteria into decision-making to ensure climate-smart urban design. Given that our knowledge about the effects of climate change on tree species will advance and should be documented, we developed an open-collaborative online database that assists stakeholders in selecting suitable species for various sites in Malaysia. Moderators will review submissions to ensure consistent application of criteria and alignment between selected answers and supporting information. Assessors can contribute to quality control by voting for assessments they agree with. Our research emphasises the importance of proactively addressing climate change challenges in urban areas and underscores the value of informed decision-making to enhance the resilience of urban tree populations.</p>

Height Above Nearest Drainage (HAND) as a Model for Rapid Flood Inundation Mapping Based on Remote Sensing and Geographic Information Systems in the Kapuas Sintang Sub Watershed

This study aims to map the flood inundation and the extent of the inundation in the study area using the HAND model. The data used in this study is DEM. The DEM is used to generate a hydrologic framework, including flow accumulation, drainage network, flow direction, elevation, and flow distance. The method used in this study is the HAND descriptor. The analysis in this study used spatial hydrological analysis and hypsometric analysis using zonal statistical tables in ArcGIS. Based on the results of the analysis of height above the nearest drainage it is known that the Kapuas Sintang sub-watershed has five classes of inundation, namely very high inundation, high inundation, moderate inundation, low inundation, and no inundation. Very high, high, and moderate inundation classes are spread over three sub-districts, namely Sintang, Dedai, and Tempunak sections. Sintang District has the widest distribution, followed by Dedai District and Tempunak District is the narrowest. Prediction of inundation area and flood area with HAND can be used to improve the new mapping model without involving additional data sources. The HAND model is a nice and simple tool that is useful for inundation studies as well as in inundation area prediction.

Scenario-based probabilistic hazard assessment for explosive events at the San Salvador volcanic complex, El Salvador

We present a scenario-based, probabilistic hazard assessment for the San Salvador volcanic complex (SSVC), a volcanic field located in the vicinity of San Salvador that includes the El Boquerón stratovolcano and 25 monogenetic vents. We define a set of likely eruption scenarios for tephra fallout and pyroclastic density currents (PDCs). The eruption scenarios range from violent Strombolian eruptions with a significant uncertainty in source position to sub-Plinian and Plinian activity fed from the central cone. The adopted methodology is mainly based on numerical modeling using Tephra2 (adopting the software TephraProb) to study tephra fallout and the branching box model and the branching energy cone model (adopting the programs BoxMapProb 2.0 and ECMapProb 2.0) to describe inertial and frictional PDCs, respectively. Despite the dominant W-WSW-trending winds, numerical results show that Plinian eruptions at El Boquerón volcano are able to deposit thick tephra layers in the metropolitan area of San Salvador city, likely reaching mass loads of the order of 100 kg/m2 (conditional probability of 50%). The simulated sub-Plinian events highlight the seasonal influence of wind patterns. In fact, the conditional probability of significant tephra sedimentation in San Salvador city is strongly reduced when eruptions occur during the rainy season. Numerical modeling of violent Strombolian eruptions is performed considering uncertainty in vent position. Results show that the conditional probability of depositing tephra mass loads higher than 10 kg/m2 at a given point reaches a maximum value of ∼7% on the NW flank of the volcano, at about 8 km from the central crater. On the other hand, very low conditional probabilities (<1%) are obtained for San Salvador city for any relevant threshold (10 kg/m2 or more) of tephra mass load during violent Strombolian events. Regarding PDCs, results show that those produced during large-scale Plinian eruptions are able to invade significant areas of the volcano surroundings, including San Salvador city. PDCs generated from the partial collapse of a sub-Plinian eruption column exhibit maximum inundation probabilities on the N, W and S flanks of the volcano. Cerro El Picacho exerts a significant shield effect on the propagation of these PDCs, with low inundation probabilities for San Salvador city (<3%). Finally, coupling published vent opening probability maps and numerical modeling of small-scale PDCs yields maximum inundation probabilities on the NW flank of the volcano, reaching maximum conditional probabilities of the order of ∼10% and values of about 5% near the village of Nuevo Sitio del Niño.

Changes of Inundation Frequency in the Yellow River Delta and Its Response to Wetland Vegetation

The spatiotemporal changes of inundation frequency in the Yellow River Delta (YRD) have profound influences on sustainable ecological protection and are also closely relevant to economic development scarcity on the coast of China. However, long-term changes of inundation frequency have remained poorly characterized. Using the Google Earth Engine (GEE) cloud platform, this study processed Landsat images to explore inundation frequency changes from 1990 to 2020 in the YRD. The results indicated that (1) The existing water index combining the classification results based on the MLM (Maximum Likelihood Method) is suitable for the mapping of the long-term water bodies, especially in the coastal regions; (2) The inundation frequency showed a clearly uneven temporal–spatial distribution. The low inundation area (LIA) is mainly intertidal natural wetlands with a declining trend, while the high inundation area (HIA) is dominated by constructed wetlands with a rising trend; (3) The use frequency of artificial ponds determines the inundation frequency of the constructed wetland. The industry development has gradually matured, causing the inundation frequency from dispersion to concentration in the constructed wetland; and (4) In the natural wetland, the LIA have increased since 2010 and have accounted for 30% in 2020. The large-scale appearance of LIA occurs with the emergence of high vegetation abundance. Spartina alterniflora salt marshes with strong reproductive ability and high abundance lead to the difficulty of wetland flooding and reduce the inundation frequency.

Response of riparian vegetation to short- and long-term hydrologic variation.

Increasing demand for river water now conflicts with an increasing desire to maintain riparian ecosystems. Efficiently managing river flows for riparian vegetation requires an understanding of the time scale of flow effects, but this information is limited by the absence of long-term studies of vegetation change in response to flow variation. To investigate the influence of short- and long-term flow variability and dam operation on riparian vegetation, we determined the occurrence of 107 plant species in 133 permanent plots of known inundating discharge along the Gunnison River in Colorado on five different occasions between 1990 and 2013. Individual species moved up and down the gradient of inundating discharge coincident with increases and decreases in mean annual flow, and the correlations between flow and species occurrence were strongest when flows were weighted by time before vegetation sampling with a median half-life of 1.5 years. Some tall, rhizomatous, perennial species, however, responded to flows on a longer time scale. Logistic regression of species occurrence showed a significant relation with inundation duration for 70 out of 107 species. Plot species richness and total vegetative cover decreased in association with desiccation at low inundation durations and with fluvial disturbance at high inundation durations. Within-plot similarity in species occurrence between years decreased strongly with increasing inundation duration. Moderate inundation durations were dominated by tall, rhizomatous, perennial herbs, including invasive Phalaris arundinacea (reed canary grass). Over the 23-year study period, species richness declined, and the proportion of rhizomatous perennials increased, consistent with the hypothesis that decreases in flow peaks and increases in low flows caused by flow regulation have decreased establishment opportunities for disturbance-dependent species. In summary, annual-scale changes in vegetation were strongly influenced by flow variation, and decadal-scale changes were influenced by decreases in fluvial disturbance from upstream flow regulation beginning decades prior to the onset of this study.

Optimization of PTFE Content in Catalyst Layer of Gas Diffusion Electrode for Alkaline Fuel Cell

Alkaline fuel cell (AFC) is historically 1st successfully applied fuel cell type. The main benefit of AFC is still possibility to use non platinum based catalysts at ambient conditions. With increase of demand for platinum metals for PEM water electrolysis and fuel cell this benefit would become more significant. Therefore it has sense to focus on AFC development.Gas diffusion electrodes (GDE) are crucial part in numerous technologies. Its main function is to enable contact of gaseous reactant with electron conductor and ionic conductor. Enlargement of contact area of mentioned three phase boundary lead to increase of electrode performance. In the case of liquid electrolyte like potassium hydroxide in AFC it is crucial to balance penetration of liquid into pores of electrode and to keep part of electrode unflooded. It must be realized in catalytic layer of GDE. Variation of temperature change electrolyte viscosity and vapor pressure both influences flooding of electrode.Beside suitable structure GDE for AFC must be stable in strong alkaline solutions. Standard GDE construction is based on combination of hydrophilic a hydrophobic materials to reach desired wettability. Also, the preparation method influences the porosity of the catalytic layer. GDE consist of three layers: catalytic, diffusion and supporting. The gas/liquid interface must be realized in catalytic layer. It is usually composed of catalyst and binder. Catalyst is chosen with respect to electrochemical reaction running on electrode thus binder must deliver desired hydrophobicity. Most typical binders are perfluorinated polymers like PTFE polytetrafluoroethylene (PTFE) with excellent chemical resistivity. Nickel, manganese, platinum, silver etc. are widely used in alkaline systems like catalysts. The most important property of the catalytic layer is the ratio of catalyst to PTFE which provides suitable hydrophobicity. The diffusion layer (GDL) is usually made of a mixture of carbon blacks/graphite and PTFE. The support layer is typically made of nickel foam or carbon paper.This work aims to optimize the ratio of PTFE to platinum catalyst in the catalytic layer. The commercial catalyst HiSPEC 40 wt. % Pt/C was used and Pt load was set to 0.5 mg/cm2. Electrodes were prepared by ink spraying technique on commercial GDL Sigracet® BC28. The ink with different ratios of PTFE to catalyst was applied to prepare GDE with PTFE content from 5 wt. % to 40 wt. %. Electrode baking under inert atmosphere was the last preparation step to increase mechanical stability.As the first characteristic the contact angle was measured. The droplet of water was placed on catalyst layer surface. The contact angle of droplet to GDE surface represents the level of hydrophobicity. A high level of hydrophobicity brings about low inundation GDE and bad contact between liquid, gas and catalyst. On the other hand, if GDE has low hydrophobicity, liquid can inundate the catalytic layer easily. As it was found already 5% of PTFE makes GDE surface hydrophobic. Higher loading of PTFE lead only to small angle increase. But significant decrease was found after GDE operation and PTFE loading over 15% is necessary to prevent further hydrophobicity decrease.In the second step prepared GDE were tested in the laboratory AFC. Pure hydrogen and pure oxygen were dosed to GDE chambers. 25% KOH solution was used as electrolyte. The I-V curve at the beginning of cell assembly, performance in time and I-V curve at the end of experiment was measure. The power of AFC with prepared electrodes improves if the hydrophobicity of GDE decreases. However, the penetration of liquid through the GDE was observed in low hydrophobic GDE in a long time testing alkaline fuel cell. Also the gradual decrease of cell performance was observed due to the flooding of the catalytic layer. After stop of operation and repeated start the performance of the cell again improved but no to the origin level. Only if the PTFE content was over 40% the performance was identical for several repeated experiments.The importance of PTFE loading in catalyst layer composition was demonstrated and its influence on AFC performance. The low loading of PTFE in GDE shows the highest performance but with fast drop. For longtime operation it is necessary to use PTFE leading at least 40%. Acknowledgment Financial support of this research by the Technological Agency of the Czech Republic under the project No TK02030001 “Research and development of advanced flow energy storage technologies” is gratefully acknowledged.

Evaluation of the Efficiency of Water Discharge using the Performance Indicator, in the Canals of the Nashik Irrigation Network

In western India, the water for irrigation is supplied by the open inundation channels of the reservoir having its predominant distribution there. The Irrigation management faces issues of less capacitated water distribution systems than its apex requirement, has irregular supply rate, low inundation efficiency, and consistency. It is important to measure the delivered water supply with required water delivery in proportion to its demand. The auto water elevated gauges which are fixed at the back and front segments of each inundation canal at the left bank channel of the Godavari river assess the discharge of supplied water during the irrigation period. In the current research, the computation would be conducted for the water delivery performance indicators such as competency, productivity, prominence, and rectitude, which are fundamental for the assessment of the irrigation and drainage system management. According to the water supply performance indicator, the inundation ability is calculated with an automatic water gauge. It is measured from the structural and transient channeling of water discharge to examine the inefficiency of water supply management. The cumulative results of the performance indicator demonstrate the enhanced methods to develop water management policies that will facilitate the irrigation planners with improved temporal consistency and reasonable water distribution.

Urban Population Flood Impact Applied to a Warsaw Scenario

The provision of detailed information on the impact of potential fluvial floods on urban population health, quantifying the impact magnitude and supplying the location of areas of the highest risk to human health, is an important step towards (a) improvement of sustainable measures to minimise the impact of floods, e.g., by including flood risk as a design parameter for urban planning, and (b) increase public awareness of flood risks. The three new measures of the impact of floods on the urban population have been proposed, considering both deterministic and stochastic aspects. The impact was determined in relation to the building’s function, the number of residents, the probability of flood occurrence and the likely floodwater inundation level. The building capacity concept was introduced to model population data at the building level. Its proposed estimation method, an offshoot of the volumetric method, has proved to be successful in the challenging study area, characterised by a high diversity of buildings in terms of their function, size and density. The results show that 2.35% of buildings and over 122,000 people may be affected by 500-year flooding. However, the foreseen magnitude of flood impact on human health is moderate, i.e., on average ten persons per residential building over the 80% of flood risk zones. Such results are attributed to the low inundation depth, i.e., below 1 m.

Assessment of coastal inundation cost due to future sea level rise: A case study for Kuwait

A preliminary assessment on the economic loss due to 1.0 m sea level rise induced inundation for the Kuwait is carried out. Kuwaiti coast of 500 km is divided into 162 segments and landward slope of the coast was assessed based on field measurements of coastal profiles. The prevailing cost of coastal land for all coastal segments are used for economic impact assessment. It is found that 29% of the coastal land in Kuwait is in the very low inundation cost category (less than 20,000 Kuwaiti Dinar (KD)/m of coast length (1 KD = 3.3 US $)); 19% is in the low inundation cost category (20,000 to 50,000 KD/m of coast length); 16% is in the moderate inundation cost category (50,000 to 100,000 KD/m of coast length); 14% in the high inundation cost category (100,000 to 200,000 KD/m of coast length) and 22% is in the very high inundation cost category (greater than 200,000 KD/m of coast length). The total inundation cost due to permanent inundation of coastal land area for 1.0 m sea level rise is 58.726 Billion KD (i.e., 193.8 billion US $), which is equivalent to 3.58 years of income for Kuwait due to crude oil export.

Salt Marsh Elevation Drives Root Microbial Composition of the Native Invasive Grass Elytrigia atherica.

Elytrigia atherica is a native invasive plant species whose expansion on salt marshes is attributed to genotypic and phenotypic adaptations to non-ideal environmental conditions, forming two ecotypes. It is unknown how E. atherica–microbiome interactions are contributing to its adaptation. Here we investigated the effect of sea-water flooding frequency and associated soil (a)biotic conditions on plant traits and root-associated microbial community composition and potential functions of two E. atherica ecotypes. We observed higher endomycorrhizal colonization in high-elevation ecotypes (HE, low inundation frequency), whereas low-elevation ecotypes (LE, high inundation frequency) had higher specific leaf area. Similarly, rhizosphere and endosphere bacterial communities grouped according to ecotypes. Soil ammonium content and elevation explained rhizosphere bacterial composition. Around 60% the endosphere amplicon sequence variants (ASVs) were also found in soil and around 30% of the ASVs were ecotype-specific. The endosphere of HE-ecotype harbored more unique sequences than the LE-ecotype, the latter being abundant in halophylic bacterial species. The composition of the endosphere may explain salinity and drought tolerance in relation to the local environmental needs of each ecotype. Overall, these results suggest that E. atherica is flexible in its association with soil bacteria and ecotype-specific dissimilar, which may enhance its competitive strength in salt marshes.

Does Ecological Water Replenishment Help Prevent a Large Wetland from Further Deterioration? Results from the Zhalong Nature Reserve, China

Ecological water replenishment (EWR) has been increasingly applied to the restoration and maintenance of wetland hydrological conditions across China since the beginning of the 21st century. However, little is known about whether EWR projects help protect and/or restore wetland ecohydrology. As one of the earliest and longest-running EWR projects in China, water has been released from the Nenjiang River into the Zhalong wetland since 2001. It is important to examine the ecohydrological effects of this EWR project. In this study, long time series remote sensing data were used to extract the water area, inundation frequency, and normalized difference vegetation index (NDVI) to explore how eco-hydrological conditions changed during the pre- (1984–2000) and post-EWR (2001–2018) periods in the Zhalong wetland. Results show that the inundation area decreased due to the reduced surface water inflow during the pre-EWR period. Similarly, monthly vegetation NDVI in the growing season generally exhibited a decreasing and an increasing trend during the pre- and post-EWR periods, respectively. In the post-EWR period, NDVI increased by 19%, 73%, 45%, 28%, 13% for the months of May through September, respectively. Due to EWR, vegetation growth in areas with low inundation frequency was better than in areas with high inundation frequency. We found that the EWR project, runoff, and precipitation contributed 25%, 11%, and 64% to changes in the NDVI, respectively, and 46%, 37%, and 17% to changes in inundation area, respectively. These results indicate that the EWR project has improved hydrological conditions in the Zhalong wetland. For further maximum benefits of EWR in the Zhalong wetlands, we suggest that implementing similar eco-hydrological projects in the future should focus on flood pulse management to increase the inundation area, improve hydrological connectivity, and create new habitats.

Global partitioning of runoff generation mechanisms using remote sensing data

Abstract. A set of complex processes contribute to generate river runoff, which in the hydrological sciences are typically divided into two major categories: surface runoff, sometimes called Hortonian flow, and baseflow-driven runoff or Dunne flow. In this study, we examine the covariance of global satellite-based surface water inundation (SWI) observations with two remotely sensed hydrological variables, precipitation, and terrestrial water storage, to better understand how apparent runoff generation responds to these two dominant forcing mechanisms in different regions of the world. Terrestrial water storage observations come from NASA’s Gravity Recovery and Climate Experiment (GRACE) mission, while precipitation comes from the Global Precipitation Climatology Project (GPCP) combined product, and surface inundation levels from the NASA Surface WAter Microwave Product Series (SWAMPS) product. We evaluate the statistical relationship between surface water inundation, total water storage anomalies (TWS; TWSAs), and precipitation values under different time lag and quality control adjustments between the data products. We find that the global estimation of surface inundation improves when considering a quality control threshold of 50 % reliability for the SWAMPS data and after applying time lags ranging from 1 to 5 months. Precipitation and total water storage equally control the majority of surface inundation developments across the globe. The model tends to underestimate and overestimate at locations with high interannual variability and with low inundation measurements, respectively.

Functional and ecophysiological traits of Halimione portulacoides and Sarcocornia perennis ecotypes in Mediterranean salt marshes under different tidal exposures

AbstractThe present paper aims to discuss the functional and ecophysiological traits of two abundant succulent halophytes in Mediterranean salt marsh systems, considering two ecotypes differing on their tidal exposure. In Halimione portulacoides the higher root/shoot (R/S) biomass ratio verified in low inundation frequency (LF) marshes, as compared with that in high inundation frequency (HF), indicates an optimal partitioning strategy, inducing differential allocation patterns along with varying environmental factors. Conversely, Sarcocornia perennis appear to have an isometric allocation strategy, based on intrinsic biomass allocation mechanisms independent from the surrounding environmental conditions. Similarly, the photosynthetic traits appear to reflect the intrinsic ecology of the species. Sarcocornia perennis habitat adaptation to HF conditions is clearly revealed by its high photosynthetic efficiency under HF conditions. On the other hand, the cosmopolitan H. portulacoides shows no differences between ecotypes, in which concerns this trait, mostly due to the high carotenoid content of the HF ecotype, which allows this specie to counteract the stress generated during submersion. Additionally, anti‐oxidant enzymatic activities revealed that S. perennis presents a high degree of stress tolerance under HF conditions, while H. portulacoides is highly adapted to LF conditions. These functional (biomass‐related) and physiological traits determine the optimal habitats for H. portulacoides and S. perennis. While H. portulacoides optimal biomass partitioning, along with its efficient anti‐oxidant defence system, makes this species fitter to LF conditions, S. perennis isometric allocation strategy, along with a higher photosynthetic efficiency under frequent flooding conditions, provides this species the mechanisms to efficiently colonize the intertidal habitat.

Improved Risk Assessment of Tsunami Inundation Based on Geospatial and Local Knowledge for Sustainable Development

Tsunami events have extensive implications for sustainable development, due to the social, economic, and environmental impacts they can cause. Take into account the competence of geospatial and local knowledge; these sources are integrated to assess tsunami risk assessment by utilizing satellite imageries. The study area of Talcahuano experienced severe damages due to the 2010 Chile earthquake and tsunami. The geospatial information of the damaged areas was identified by processing the surface reflectance values between pre- and post-disaster images of the satellite optical and SAR data. The DEM data was also employed to delineate areas according to the inundation height data. Local information of tsunami inundation was generated through a DIG participatory mapping. Both types of inundation maps showed good agreement with the results of field surveys. Furthermore, a map of the potential tsunamiinundation zone was produced to aid integrated risk assessments in the area. The map showed areas with high, medium, and low inundation level adopted from the satellite images and the DIG map. Keywords: Tsunami Inundati Satellite Imageries, Optical and SAR Sensor, DIG, Disaster Risk Reduction