Water Level Depth Research Articles

Statistical Analyses of the Effect of Precipitation on Levels of Underground Water in Central Sulaimani Province

In this study, we tried to shade light on effect of precipitation on the underground water level in Central Sulaimani Province, based on collected data of precipitation of different weather station in Sulaimani, Bakrajo, Bazyan. Data of all the wells, in practical fields using electrical sounder for measuring weather levels. GPS was also used to detect the astronomical position of the wells and define their places on map using ArcGis10.8. On two different time periods, the water levels were measured including Autumn, when the underground water position is in its mining level, from 17-9-2021 to 13-11-2021, and on Spring from 4-3-2022 to 17-4-2022 when water is at lightest level. To compare water levels before and after precipitation, another method of quantitative analysis based on statistical results and Pearson Coefficient to realize correction of degree of precipitation and underground water levels. Moreover, effect of precipitation on underground water level has been shown using SPSS-26. The aim of this research is to define the relation and precipitation effects on underground water level, and ultimately propose a scientific plan to preserve the underground water level. As a result, according to Pearson Coefficient Correlation, there is negative relation between precipitation and the depth of underground water level. This means that the depth to reach underground water is reduced when the precipitation increases. Furthermore; precipitation has an estimated effect of 90.2% on static level of underground water, and of 67.6% on dynamic level of underground water.

Study of electrical resistivity vertical changes in carbonate oil-bearing reservoirs to determine the depth of free water level

Abstract The purpose of the study is to establish the depth of the free water level (FWL), the zone of oxidized oil, the oil-water transition zone, the zone of maximum and decreasing resistivity. Correct understanding of initial oil saturation zonation in carbonate oil-bearing reservoirs is very important for development planning. The article proposes a method for express assessment of the FWL depth and initial oil saturation zonation in carbonate oil-bearing reservoirs based on electrical resistivity study. The values of electrical resistivity determined from induction logging curves in more than 200 wells were used as initial data. The vertical change in the electrical properties is considered using the resistivity values of oil-bearing reservoirs averaged over all wells. The initial oil saturation zonation was analysed using the graphs of electrical resistivity against depth. As a result of the work done, the following conclusions were made regarding the zonation of initial oil saturation and the possible geological characteristics of carbonate oil-bearing reservoirs: 1) based on the graphs of electrical resistivity against depth it is possible to distinguish 3 zones of initial oil saturation: oil-water transition zone above FWL, zone of maximum resistivity in the middle part of the deposit, and zone of decreasing resistivity in the upper part of the deposit; 2) in general, the initial oil saturation in the reservoir (as a function of the electrical resistivity) upward from the initial FWL depth does not grow exponentially, as in the Leverett function, but linearly in each zone. Proposed express method for initial oil saturation zonation in carbonate reservoirs provides novel information for formation testing and perforation planning. In oil-water transition zone it is recommended to use the gentlest methods of perforation and production intensification to preserve the integrity of the oxidized oil zone, since this zone is water confining and can prevent premature water flooding of the product.

Using a comparative of DRASTIC and Bayesian weights of evidence approach to assess transboundary aquifer vulnerability in a data scarcity region: Tuli-Karoo aquifer

Study regionThe Tuli-Karoo Transboundary Aquifer system is shared among Botswana, South Africa and Zimbabwe. It hosts a complex aquifer predominately of sand, heavily tapped in South Africa and sandstone substantially used in Botswana threatening it’s quality. Study focusTwo vulnerability models, the classic DRASTIC (Depth to water table [D], Recharge to the aquifer [R], Aquifer media [A], Soil media [S], Topography [T], Impact of vadose zone [I], Conductivity [C]) and the bayesian based, Weights of Evidence (WofE), were used to delineate zones vulnerable to groundwater contamination under limited nitrate observations. New hydrological insights for the regionThe study revealed that the generic DRASTIC vulnerability results were comparable to the WofE, for the highly vulnerable zones, as both had an area under the curve (AUC) below 0.6. The high vulnerability was attributed to the shallow depth of water level, fractured geological condition (based on transmissivity) and high net recharge rate in and around the Tuli-Karoo Aquifer. However, there are differences in spatial variability in the low/medium vulnerability zones. WofE was superior in capturing spatial variability of groundwater vulnerability. Considerations must therefore be provided, under data scarcity, to incorporate proxies that include landuse-landcover and population density as evidential layers. Overall, WofE performs better due to better prediction power under data-scarcity conditions. This study recommends that under data scarcity, high predictive models like WofE should be used for environmental planning and groundwater protection strategies.

Hydrometeorological conditions drive long-term changes in the spatial distribution of Potamogeton crispus in a subtropical lake.

Globally, anthropogenic disturbance and climate change caused a rapid decline of submerged macrophytes in lake ecosystems. Potamogeton crispus (P. crispus), a species that germinates in winter, explosively expanded throughout many Chinese lakes, yet the underlying mechanism remained unclear. Here, this study examined the long-term changes in the distribution patterns of P. crispus in Lake Gaoyou by combining remote sensing images and hydrometeorological data from 1984 to 2022 and water quality data from 2009 to 2022. It aims to unravel the relationships between the distribution patterns of P. crispus and hydrometeorological and water quality factors. The results showed that the area of P. crispus in Lake Gaoyou showed a slight increase from 1984 to 2009, a marked increase from 2010 to 2019, followed by a decline after 2020. Spatially, P. crispus was primarily distributed in the western and northern parts of Lake Gaoyou, with less distribution in the central and southeastern parts of the lake. Wind speed (WS), temperature (Temp), water level (WL), ammonia nitrogen (NH3-N), and Secchi depth (SD) were identified as the key factors regulating the variation in the P. crispus area in Lake Gaoyou. We found that the P. crispus area showed an increasing trend with increasing Temp, WL, and SD and decreasing WS and NH3-N. The influence of environmental factors on the area of P. crispus in Lake Gaoyou varied among seasons. The results indicated that hydrometeorology (WS, Temp, and WL) may override water quality (NH3-N and SD) in driving the succession of P. crispus distribution. The findings of this study offer valuable insights into the recent widespread expansion of P. crispus in shallow lakes across Eastern China.

Identification of liquefaction potential in Kampung Melayu Bengkulu based on water level depth (watertable)

Abstrak. Wilayah Kampung Melayu memiliki kondisi litologi batuan yang tersusun atas formasi undak alluvium (Qat) yang terdiri dari pasir, lempung, lanau, dan kerikil yang bersifat lepas sehingga dapat memicu terjadinya fenomena likuifaksi apabila terjadi gempa bumi. Penelitian ini bertujuan untuk mengetahui potensi likuifaksi berdasarkan nilai resisitivitas litologi batuan bawah permukaan bumi dan kedalaman muka air tanah (watertable) pada 40 titik Sounding di daerah penelitian dengan menggunakan metode Vertical Electrical Sounding (VES) konfigurasi Schlumberger. Hasil penelitian menunjukkan bahwa lapisan bawah permukaan di Kecamatan Kampung Melayu terdiri dari batuan alluvium, mencakup lempung, kerikil, pasir, napal, air payau, dan air tanah, dengan nilai resistivitas berkisar antara 0 hingga 508 Ω.m. Keberadaan formasi alluvium ini menjadi ancaman yang serius pada saat terjadi gempa bumi yang dapat bepotensi terjadinya likuifaksi. Kedalaman muka air tanah (watertable) di wilayah ini relatif dangkal, berkisar antara 1 hingga 25 meter, dengan nilai resistivitas antara 5,1 hingga 40 Ω.m. Adanya zona jenuh air yang dangkal dan struktur batuan alluvium menunjukkan potensi resiko likuifaksi. Abstract. The Kampung Melayu area has rock lithology conditions which are composed of alluvium step formations (Qat) consisting of loose sand, clay, silt and gravel which can trigger liquefaction phenomena when an earthquake occurs. This research aims to determine the liquefaction potential based on the lithological resistivity values of the earth's subsurface rocks and the depth of the groundwater table (watertable) at 40 sounding points in the research area using the Schlumberger configuration Vertical Electrical Sounding (VES) method. The research results show that the subsurface layer in Kampung Melayu District consists of alluvium rock, including clay, gravel, sand, marl, brackish water and groundwater, with resistivity values ranging from 0 to 508 Ω.m. The existence of this alluvium formation poses a serious threat during an earthquake which could potentially cause liquefaction. The depth of the groundwater table (water table) in this area is relatively shallow, ranging from 1 to 25 meters, with resistivity values between 5.1 and 40 Ω.m. The existence of shallow water saturated zones and alluvium rock structures indicate a potential risk of liquefaction.

Assessing the impacts of ice penetration on monitoring water levels of high-latitude and -altitude lakes from CryoSat-2 altimetry

The CryoSat-2 satellite provides high-precision and long-term monitoring of global lake levels, offering advantages for water resource management, ecological protection, and disaster warning. However, the lake ice penetration by radar electromagnetic waves of CryoSat-2 altimetry tends to result in underestimation of water levels for lakes in high latitudes and altitudes. By contrast, the laser altimetry of ICESat-2 enables us to obtain the height measurements from lake ice surface and the ice penetration impacts on lake levels can be nearly ignored in the ICESat-2 elevation product. After converting the CryoSat-2 and ICESat-2 altimetry data to the same datum and height reference system, the water level difference of (near-) synchronous observations between the two satellites could be mainly attributed to the influences by the lake ice penetration from CryoSat-2 data. In this study, totally 257 lakes in high-latitude (north of 50°N) and high-altitude (the Tibetan Plateau, TP) regions that are covered by both CryoSat-2 and ICESat-2 satellite tracks are examined to explore the characteristics of ice penetration impacts on water level measurements. The altimetry data during unfreezing seasons (June to October) are used to correct the systematic height biases of these two satellite measurements, thus their water level differences during freezing seasons (November to May of the following year) are deemed as the influences of ice penetration on lake level measurements by CryoSat-2 radar altimetry. The results show that the maximum underestimation depth of water level for each lake varies within the range of 0.01–3.47 m, with an average of 0.90 m. Particularly in North America with a dense distribution of lakes, the underestimation of lake levels by CryoSat-2 gradually ascends with increasing latitude. CryoSat-2 underestimates lake levels in Europe and the TP less than in North America. Among different months, the lake ice leads to the maximum underestimation on the water level by CryoSat-2 altimetry in March. The spatial and temporal characteristics of lake ice impacts on the water level measurements by CryoSat-2 altimetry would be an essential reference for quantifying and reducing the uncertainties of satellite radar altimetry for monitoring inland water dynamics.

Machine-Learning-Based Deformation Prediction Method for Deep Foundation-Pit Enclosure Structure

During the construction of deep foundation pits in subways, it is crucial to closely monitor the horizontal displacement of the pit enclosure to ensure stability and safety, and to reduce the risk of structural damage caused by pit deformations. With advancements in machine-learning (ML) techniques and correlation analysis in engineering, data-driven methods that combine ML with engineering monitoring data have become increasingly popular. These methods offer benefits such as high prediction accuracy, efficiency, and cost effectiveness. The main goal of this study was to develop a machine-learning method for predicting the enclosure deformation of deep foundation pits. This was achieved by analyzing the factors influencing deep foundation-pit enclosure deformation and incorporating historical cases and monitoring reports. The performance of each machine-learning prediction model was systematically analyzed and evaluated using K-Fold cross validation. The results revealed that the random forest model outperformed the other models. The result of the test data showed that the random forest model achieved an R2 of 0.9905, an MAE of 0.8572 mm, and an RMSE of 1.9119 mm. Feature importance analysis identified the depth of enclosure structure, water level, surface settlement, axial force, and exposure time as the most critical factors for accurate prediction. The depth of the enclosure structure had an especially significant impact on the prediction of enclosure deformation.

Studi Sifat Fisika Tanah Gambut pada Kebun Karet dan Kelapa Sawit Rakyat di Kecamatan Rasau Jaya Kabupaten Kubu Raya

This study aims to study the differences in the physical properties of peat soils in rubber and oil palm plantations in Rasau Jaya III Village Rasau District Kubu Raya District. The parameters of this study are, peat depth, peat maturity, measurement of ground water level depth, content weight, water content capacity field, total porosity, permeability, and some chemical properties, peat soil in people's rubber and oil palm plantations in Rasau Jaya District, Kubu Raya Regency. Measurement of peat depth is taken up to the mineral soil boundary, has a 74 cm rubber peat depth and 66 cm oil palm. The level of maturity of both fields at the sapric level. The water resistant surface on rubber land is 70 cm and oil palm land is 58.8 cm. Average bulk density of depth 0 – 30 cm rubber land 0.34 g/cm3, palm 0.31 g/cm3. Depth 30-60 cm rubber 0.28 g/cm3, palm 0.38 g/cm3. Average field water capacity depth of 0-30 rubber fields 74, 63% palm 85.19%. While at a depth of 30-60 cm rubber land has 71.58% oil palm area of 84.58% vol. The average porosity of total soil depth of 0-30 cm palm oil is 86.96% higher than rubber area 82.37%. The average total porosity of soil at a depth of 30-60 cm is lower oil palm 81.82% rubber land 86.82% and both lands are classified as very porous criteria. The mean permeability values based on the t-test results were not significantly different.

Three-dimensional hydro-mechanical coupling numerical simulation of shield-driven cross-river twin tunnels: A case study

With the rapid development of urban underground space, the construction of shield-driven cross-river twin tunnels is increasing, and the complex hydro-mechanical coupling effects and twin-tunnel interactions bring huge construction risks to such projects, which have attracted more and more attention. This study aims to understand the excavation effects induced by shield driving of cross-river twin tunnels through numerical simulation. A refined three-dimensional numerical model based on the fully coupled hydro-mechanical theory is established. The model considers the main components of the slurry pressure balance shield (SPBS) machine, including support force, jacking thrust, grouting pressure, shield-rock interaction and lining-grouting interaction, as well as the detailed construction process. The purpose is to examine the excavation effects during construction, including rock deformation around tunnels, the change in pore pressure, and the response of the lining. The results show the influence range of twin-tunnel excavation on rock deformation and pore pressure, as well as the modes of lining response. In addition, this study also systematically investigates the effects of water level fluctuation and burial depth on twin-tunnel excavation. The results indicate that the increase of water level or burial depth will enhance the excavation effects and strengthen the twin-tunnel interactions. These results provide useful insights for estimating the construction impact range and degree of twin tunnels, and serve as basic references for the design of cross-river twin tunnels.

Ambiguities in implementing regulations for sustainable groundwater resources development in Vietnam with a case study of Tra Vinh province in Mekong Delta

Study regionThe study region is the coastal Tra Vinh province located in Mekong Delta, Vietnam Study focusThe study aims to clarify the ambiguities in implementing Vietnam's regulation on restrictions of groundwater abstraction in Mekong Delta. Three ambiguities were identified, namely, how should half of the saturated thickness of the unconfined aquifer be computed; is the water level depth of 30 m for the confined aquifer sufficient to prevent seawater intrusion and land subsidence; and why is the interference of water use rights of neighbouring provinces not considered. Numerical groundwater flow, saltwater transport and land subsidence were constructed for Tra Vinh province to assess water level requirements from Vietnam regulation and important constraints for groundwater sustainability. The model results show that although all scenarios satisfy groundwater level requirements from the Vietnam regulation, only the mitigation scenario combined with reducing abstraction and increasing recharge can lead to sustainable development. New hydrological insights for the regionThe current groundwater abstraction in Tra Vinh province has caused groundwater storage depletion and induced seawater intrusion, land subsidence, and captured groundwater inflow from neighbouring provinces. When the business as usual continues, seawater may intrude 4–5 km inland and cumulative land subsidence may reach 1.5 m by 2100. Reduction of current abstraction by 50% supplemented with the increase of recharge by 1.5 times in the dunes can lead to sustainable development.

Determination of the Tolerance of Shallot Varieties at Water Level Depth by Water-saturated Cultivation in Tidal Land

Determination of the Tolerance of Shallot Varieties at Water Level Depth by Water-saturated Cultivation in Tidal Land

Stability on the Excavation Surface of Submarine Shield Tunnel Considering the Fluid–Solid Coupling Effect and the Equivalent Layer

The support pressure on an excavation surface is a critical factor in the ground deformation and excavation stability of a submarine shield tunnel. The shield tail gap and the disturbance zone of grouting behind the tunnel wall are also important influencing factors. However, the effects of these factors on excavation stability are difficult to quantify. Consequently, a homogeneous, elastic, and annular equivalent layer is employed to simulate the thin layer behind the tunnel wall. Using COMSOL Multiphysics software, the effects of the water level depth, the thickness of the equivalent layer, the diameter of the shield tunnel, and the internal friction of soil and tunnel burial depth on the excavation deformation and ground surface subsidence of a submarine tunnel are considered with regard to the fluid–solid coupling effect. The result show that the surface subsidence of the case with respect to the fluid–solid coupling effect and the equivalent layer is larger than that without interstitial fluid and the equivalent layer, indicating that the present model can better simulate the stability of tunnel excavation. Therefore, it is important to consider the impact of the fluid–solid coupling effect and the equivalent layer on the deformation of the excavation face and ground surface subsidence.

Decision Support System and Fuzzy Logic Controller for Capillary Irrigation System

Purpose: Different irrigation systems exist and they all possess various degrees of benefits in enhancing food sufficiency. In this study however, the enhancement of capillary irrigation system through an integrated fuzzy logic controller with Decision Support System (DSS) to ensure improvement in water saving for irrigation thereby improving crop yield towards food security was examined and achieved.
 Methodology: An integrated fuzzy logic controller with Decision Support System (DSS) for capillary irrigation system was adopted for the enhancement of water saving for irrigation. By using this method, the challenges of irrigation management which is prevalent with capillary irrigation system is minimised using the fuzzy logic controller. An Internet of things (IoT) based weather station for computation of potential evapotranspiration (PET), for measuring rainfall and a VH400 moisture content sensor for monitoring the volumetric water content of soil, were some facilities used to control the water level depth (WLD) autonomously through a fuzzy controller simulated in MATLAB and implemented on Arduino Mega.
 Findings: The soil moisture content (SMC) depicts that fuzzy controlled water level depth (WLD) is able to compensate reduction of water in crop medium that took place due to plant water uptake which changes daily. The result proves that dynamics of water supply depth has substantial effects on the water absorption flow rate, wetting pattern, soil water content and cumulative infiltration which are proportional to the water supply depth decrement. 
 Unique Contribution to Practice: An integrated fuzzy logic controller with Decision Support System (DSS) is a new technique proposed for managing capillary irrigation system as it offers enhanced water saving capacity (irrigation volume) based on crop demand.

Assessment on Water Quality Parameter and Nutrients Level of Nyatuh River in Relations with Macrobrachium Rosenbergii Prawn Populations.

In order to determine the safety level of water parameters and nutrients in the natural environment of fish and freshwater prawn in Nyatuh River, Terengganu, Malaysia, it is necessary to conduct an assessment of water quality parameters. Due to its important, a study was conducted to assess the water quality parameter and nutrients contents from Nyatuh River of Setiu Terengganu in relations to the population of freshwater prawn, Macrobrachium rosenbergii caught along the Nyatuh River basin. Total of four expeditions and five stations at different tidal condition for the water quality parameter were assessed during the study. From the results achieved, the overall temperature varied between (26.56°C-29.30°C), dissolved oxygen, DO (3.59 mg/L-6.50 mg/L), pH (4.99-7.01), salinity (0.01ppt-4.22ppt), depth (2.71 m-5.54 m) while for ammonia (0.01 mg/L-0.24 mg/L), nitrite (0.01 mg/L-0.05 mg/L) and phosphate (0.01 mg/L-0.12 mg/L). While the number of prawns caught are 176, 160, 102 and 68 for Expeditions 1, 2, 4 and 3, respectively. Possibly, the heterogeneous number of prawns caught is a result of significant differences in water level depth during high tides and low tides, as well as a fluctuation in the ammonia concentration levels in each of the stations and expeditions. For statistical analysis, the temperature showed no significant difference between the expedition, stations and tidal. That is p = 0.280, p > 0.05 and F = 1.206, respectively. While dissolved oxygen, DO, showed no significant difference as well, that is p = 0.714, p > 0.05 and F = 0.737. However, the level of water depth was significantly different between expedition, station and tidal, that is p = 0.000, p < 0.05 and F = 3.120. Ammonia, on the other hand shows no significant difference between expedition, station and tidal, that is p = 0.476, p > 0.05 and F = 0.973. The same goes for nitrite and phosphate concentration. There was no significant difference between expedition, stations and tidal, that is p = 0.569, p > 0.05 and F = 0.879 and p = 0.247, p > 0.05, F = 1.255, respectively. In Expedition 1, the good water quality parameter and very low ammonia concentration resulted in a larger prawn population as compared to other expeditions. The distribution or mixture of prawns caught is heterogeneous at different stations due to the significant differences in water depth and also to the fluctuation in water quality due to varying ammonia levels. In conclusion, the water quality in Nyatuh River fluctuated across expeditions, stations, and tides, as well as significant differences in water level depths between high and low tides. Due to the rapid growth and importance of industrial and aquaculture operations along the river, extra attention should be devoted to avoid the impact of excessive pollutant in order to protect the ecosystem.

Use of electrical resistivity tomography to reveal the shallow freshwater–saline interface in The Fens coastal groundwater, eastern England (UK)

The Fens is a region that contributes 11% of the agri-food economy from just 4% of the agricultural land covering England (UK). This region is vulnerable to soil salinisation from sea-level rise with estimated 100-year flood events projected to be observed up to every 2 years by 2100. Seawater intrusion and upwelling of saline groundwater can provide an additional pathway; however, the area’s groundwater has not been assessed and the risk is unknown. This study used data from the British Geological Survey’s stratigraphic core archive to produce the first stratigraphic map of the loosely consolidated Holocene deposits in the South Holland–Holbeach Marsh region. There is a sandy unconfined aquifer towards the coast, a semiconfined central region with a silty cap and a clay confining cap in the north region. Electrical resistivity tomography data indicate water level depths of 0.58 ± 0.37 m above mean sea level (msl) in February 2021 and 0.01 ± 0.72 m msl in August 2021. The saline–freshwater boundary was at 1.70 ± 0.82 m msl in February 2021, deepening to 2.00 ± 1.02 m msl in August 2021, but the only evidence of seasonal fluctuation was within 10 km of the coast. A potential, but unverified, freshwater lens up to 3.25 m thick may exist beneath the surface. These results suggest that freshwater–saline interface fluctuations may primarily be driven by surface hydrology and would be vulnerable to climate-change-induced future variations in factors that affect surface water.

How degraded are the peatland and forest ecosystems in the Bieszczady Mountains (Central Europe)? An assessment using long‐term records

AbstractPeatland and forest ecosystems located in the Bieszczady Mts. (Carpathians, Central Europe) have been affected by human activity since the Neolithic, with this impact intensifying over time. We conducted long‐term studies to: (i) determine past peatland and forest development and current ecological state; (ii) assess the role of different factors that influenced ecosystem development over the last 3750 years; and (iii) determine natural reference conditions as a basis for the restoration of degraded mountain bogs and forests in the region. High‐resolution multi‐proxy palaeoecological analyses (plant macrofossils, pollen, testate amoebae, macro and microcharcoal, peat stoichiometry and stable isotopes), supported by radiocarbon dating, were performed on peat cores from an ombrotrophic peatland. Our study revealed that the peatland and forest ecosystems have been impacted by both climate change and human activity (fires, deforestation, and grazing) over the past 3750 years and that massive deforestation took place 400 years ago. Changes in forest composition led to the intensification in erosion between 3700–1500 cal. BP and over the past 350 years. Drainage resulted in hydrological disturbances but did neither stop the peat formation process nor decreased the abundance of species forming the natural peat plant communities indicative of oligotrophic conditions. However, hydrological disturbances shifted peat plant composition to dry‐adapted species (e.g. dwarf shrubs, Pinus sylvestris). Average water level depth fluctuated between ca. 10 and 25 cm over the last 3750 years; thus these are conditions that could be considered as hydrological reference for restoration measures. Our approach to identify natural reference conditions may be expanded to peatlands from other temperate mountain ranges.

Digital Core Analysis of Capillary Pressure in Sandstone

This research aimed to obtain the petrophysical parameters of the capillary pressure of a sandstonefrom 3D modelling of high-resolution rock images. By integrating a number of 2D slice results, a plot of capillarypressure vs water saturation was built. When performing digital simulations using 512 x 512 x 512 pixels, theeffect on the resulting image was clearly seen using interactive thresholding. The obtained porosity was 29.5%while the permeability was obtained through iteration as 3942 mD, a quite large value since it is a synthetic core.Meanwhile, at the depth of free water level of 984 ft, the capillary pressure is found to be 167.36 psi with watersaturation at 4%.

Stem Growth of Horse Chestnut (Aesculus hippocastanum L.) under a Warming Climate—Tree Age Matters

This research provides new information about the effect of drought on horse chestnut growth (Aesculus hippocastanum L.) in different ages. Global climatic scenarios predict a higher frequency of heatwaves and drought periods; however, investigations into the growth reaction of horse chestnut to drought are completely lacking. Approximately 50-year-old solitary, 100-year-old solitary, and 100-year-old canopy horse chestnut trees in a floodplain area were investigated. Growth reactions measured using automated dendrometers with respect to meteorological variables and water table depth were investigated during the years 2019–2021. Cambial activity was shown to be driven by tree age, as younger trees had higher stem radial increment rates. Both mature tree groups suffered from a low depth of water level and from higher sensitivity to meteorological variables, as growth was limited when mean daily vapor pressure deficit (VPD) exceeded 600 Pa. Together with a lower probability of growing days and a shorter growing season (GS) with earlier cessation of growth resulted in a lower total year radial increment (GRO) and basal area increment (BAI) when compared to younger trees. The young trees also exhibited lower tree-water-deficit-induced stem shrinkage (TWD) across all the studied years. Overall, horse chestnut trees in this floodplain area could be endangered by the decreasing level of soil water, with a greater age exacerbating the effects of drought. The year water deficit exceeded −340 mm in this locality every year, which has to be compensated for by regular flooding.

Identification and demarcation of ground water level with the help of horse power wise motor pumps in Bhokarbari irrigation project command area of Jalgaon district

Horse power of motor pumps installed on the wells is one of the significant indicators help to identify and demarcate groundwater levels. In the present paper an attempt is made to display village wise spatial distribution of horse power wise motor pumps to identify the depth of ground water levels. When depth of ground water level is deep, farmers prefer high HP motor pumps to irrigate the fields and vice a versa. In the Bhokarbari command area, MSEB office has supplied electric connections to 2029 agricultural wells, out of them 89.84% wells have supplied below than 3 HP connections. It is concluded that due to highest number of wells, utilization of groundwater is more; hence most of the farmers are suffering from insufficient supply of groundwater to irrigate their fields. It revealed that, in the central part Intensive irrigated area are observed in the command area of the project. The central part of the study area is having good amount of groundwater.

Evaluating irrigation status in the Mekong Delta through polarimetric L-band SAR data assimilation

For sustainable food production in the Mekong Delta, local information on irrigation status is essential for allocating water resources efficiently at the community level. ALOS-2 PALSAR-2 L-band SAR can be used to detect submerged and nonsubmerged soil covered by rice plants at a spatial resolution compatible with field observation but a low temporal resolution. In this study, a new multiscale data assimilation technique is developed to estimate the spatiotemporal dynamics of field water levels at a temporal resolution appropriate to inform decision-making on when to initiate irrigation. The method employs an irrigation model based on parameters representing farmers' irrigation practices. ALOS-2 PALSAR-2 data are used to derive the hydrological parameters of the model, including an irrigation parameter representing how deep the field water level dropped until the next round of irrigation was initiated. We developed observation operators for the soil submersion status under vegetation and spatial submersion percentages instead of assimilating soil moisture products. The study uses ALOS-2 PALSAR-2 data (25–100 m spatial resolution, approximately every 42 days) over the Mekong Delta and experimental data collected in situ for model initialization and validation. The estimated irrigation parameter controlling the maximum depth of field water level showed spatio-temporal consistency with the ground-observed value (RMSE = 4.24 cm). The values of the parameters also showed spatial consistency with respect to DEM data; he paddies with low irrigation model parameter values were prone to be located in low-elevation zones (<2 m), whereas high model parameters values tended to be located in paddies in the high-elevation zones (>3 m).The results show promising applications using L-band SAR observations for monitoring paddy field water level, for irrigation practices and for estimation of the water consumption and of methane emissions.