Total Amount Of Water Research Articles

Grass (Poa annua L.) cover for eight years as an effective strategy for recovering soil moisture

Deep soil desiccation has become a major obstacle to restoring vegetation in the Loess Plateau region of China. The restoration of deep soil water plays an important role in ecosystem health. In the present study, we compared the effects on moisture variations in deep dry soil of grass cover and clean tillage treatments based on in-situ soil column monitoring for eight years. The results showed that the dry soil layers could temporarily disappear and reappear again with rainfall under clean tillage. However, grass cover effectively increased the deep soil moisture. Grass primarily consumed soil moisture from the shallow layer (0–2 m), and the total amount of water consumed during the whole growth period was less than the annual rainfall in dry years. The average soil desiccation index decreased by 24.20 % and the deep soil water moisture (2–10 m) recovered from 7.5 % to 12.8 % after eight years, with an annual average recovery of 0.66 %. Thus, it would take half a year to recover to the stable field capacity and 14 years to reach the field capacity. Recovery of the soil moisture also depended on the rainfall supply. We found that precipitation had an obvious lagged effect of approximately two years on the supply of deep soil moisture. Our findings contribute to understanding how to alleviate dry soil layer, with potentially helpful implications for the ecological health in arid and semiarid regions.

Trade-off between the future water resource utilization and grain production in a water-deficient region from the perspective of the Water−Land−Grain nexus

The utilization and future evolution of water resources in water-deficient regions will have a significant impact on sustainable agricultural development. The trade-off between water resource utilization and grain production in the Daqing River Basin (DRB) was explored, and the characteristics of the future evolution of the water − land − grain system was analyzed. The main planting patterns of farmland in the DRB are winter wheat, spring maize, summer maize, or a winter wheat − summer maize rotation. The total water consumption and supply are 61.6 × 108 and 54.4 × 108 m3, respectively. The water supply gap is approximately 7.2 × 108 m3, which is mainly supplemented by the overexploitation of groundwater. Under the current land use structure, grain production in the DRB has achieved self-sufficiency, but excessive water consumption in agricultural production has led to severe groundwater overexploitation. Despite the exploration and implementation of a fallow land policy in the DRB, the quantity of water resources conserved currently falls significantly short in comparison to the extent of groundwater overexploitation. From the trade-off between water resource utilization and grain production, if winter wheat areas were left completely fallow, or winter wheat planting regions establish three crops in two years or a single crop in a year, the total amount of irrigation water that could be saved was 18.4 × 108, 7.5 × 108, and 15.2 × 108 m3, although the grain production capacity would be reduced by 31 %, 12 %, and 24 %, respectively. This study proposes prioritizing fallow areas in the winter wheat planting regions with high water demand located in the Diandong Plain, and changing the current system of two crops a year to three crops in two years or a single crop a year. The implementation of this approach is anticipated to alleviate the strain on water resources. To achieve the control of groundwater overexploitation and balance the supply and demand of water resources, it is necessary to continue to expand the fallow area of winter wheat in the eastern and southern plains of Baiyangdian by approximately 25.3 × 104 hm2, or increase the amount of water diverted from outside the basin by approximately 7.20 × 108 m3. By 2030, the DRB will face the dual pressures of both water and grain security, with a water resource gap of 13.8 × 108 m3. It is therefore necessary to increase inter-basin water transfer or continue to expand the fallow area of winter wheat in the future.

Responses of non-native and native plant species to fluctuations of water availability in a greenhouse experiment.

Water availability strongly influences the survival, growth, and reproduction of most terrestrial plant species. Experimental evidence has well documented the effect of changes in total amount of water availability on non-native vs. native plants. However, little is known about how fluctuations in water availability affect these two groups, although more extreme fluctuations in water availability increasingly occur with prolonged drought and extreme precipitation events. Here, we grew seven non-native and seven native plant species individually in the greenhouse. Then, we exposed them to four watering treatments, each treatment with the same total amount of water, but with different divisions: W1 (added water 16 times with 125 mL per time), W2 (8 times, 250 mL per time), W3 (4 times, 500 mL per time), and W4 (2 times, 1000 mL per time). We found that both non-native and native plants produced the most biomass under medium frequency/magnitude watering treatments (W2 and W3). Interestingly, non-native plants produced 34% more biomass with the infrequent, substantial watering treatment (W4) than with frequent, minor watering treatment (W1), whereas native plants showed opposite patterns, producing 26% more biomass with W1 than with W4. Differences in the ratio of root to shoot under few/large and many/small watering treatments of non-native vs. native species probably contributed to their different responses in biomass production. Our results advance the current understanding of the effect of water availability on non-native plants, which are affected not only by changes in amount of water availability but also by fluctuations in water availability. Furthermore, our results indicate that an increased few/large precipitation pattern expected under climate change conditions might further promote non-native plant invasions. Future field experiments with multiple phylogenetically controlled pairs of non-native and native species will be required to enhance our understanding of how water availability fluctuations impact on non-native invasions.

A large-scale evaluation of machine learning algorithms in mid-term water demand forecasting

ABSTRACT Water utilities currently face challenges in accurately measuring user-end consumption as they have to visit every conventional meter that is installed in their service area. This study explores the use of accessible machine learning models to forecast water demand at two crucial temporal scales, addressing practical needs such as customer billing. To draw meaningful conclusions, these models were tested and trained from actual user-end water consumption data from over 2.1 million customers over a 10-year period. These data were provided by the Water and Sewage Company of Greece (EYDAP). The large-scale experiment included the use of statistical models (ARIMA and SARIMA), deep learning [long short-term memory (LSTM)], and clustering techniques (k-NN algorithm). The model with the best performance was ARIMA, outperforming all the other models including the more complex ones. The LSTM model did not perform as expected in predicting water consumption, it excelled only in predicting the total amount of water consumed. These forecasts can be valuable tools for water utility companies, aiding in tasks such as customer billing and water balance calculations. This paper covers all the necessary steps that must be taken to achieve meaningful user-end water consumption forecasts, from raw data preprocessing to hyperparameter tuning for machine learning algorithms.

Assessment of the properties of mortars made of sorel cement

The purpose of laboratory tests was to determine the effect of sodium silicate and selected hydrophobic agents on the basic physical parameters and freeze-thaw durability of mortars made with Sorel cement in variable proportions. In order to determine the mortars’ parameters, samples of the dimensions of 4x4x16 cm and boards of the diameters of 1x4x16 cm were prepared. Parameters such as water absorption, capillary absorption, compressive and flexural strength and frost resistance were tested. Mortar supplemented with sodium silicate in the quantity of 2.6% of all components demonstrated the best properties. None of the other hydrophobic agents that were used to mitigate the negative effects of water on Sorel cement mortars demonstrated such positive properties. Flexural strength tests of all mortar batches, performed on cuboid samples and boards of the thickness of 1 cm, demonstrated a similar improvement in strength. The lowest value of compressive strength was recorded for the reference batch at 46.6 MPa, whereas the highest value was recorded for the second batch containing sodium silicate, at 49.8 MPa. During the testing of frost resistance, the lowest reduction of compressive and flexural strength was recorded for the reference mortar and for mortar with sodium silicate. All mortars were varied in the MgO/MgCl2 ratio and the total amount of water, the observed effects may be caused by other variables. However it is possible to notice the positive effect of selected hydrophobic agents.

Integrating water balance mechanisms into predictions of insect responses to climate change.

Efficient water balance is key to insect success. However, the hygric environment is changing with climate change; although there are compelling models of thermal vulnerability, water balance is often neglected in predictions. Insects survive desiccating conditions by reducing water loss, increasing their total amount of water (and replenishing it) and increasing their tolerance of dehydration. The physiology underlying these traits is reasonably well understood, as are the sources of variation and phenotypic plasticity. However, water balance and thermal tolerance intersect at high temperatures, such that mortality is sometimes determined by dehydration, rather than heat (especially during long exposures in dry conditions). Furthermore, water balance and thermal tolerance sometimes interact to determine survival. In this Commentary, we propose identifying a threshold where the cause of mortality shifts between dehydration and temperature, and that it should be possible to predict this threshold from trait measurements (and perhaps eventually a priori from physiological or -omic markers).

Exploring available water resources in Bahraich district of Uttar Pradesh: A comprehensive study

Present study was carried out during 2018–22 at Bahraich, Uttar Pradesh focusing on groundwater, runoff, and canal water suggesting that a sizable database is essential for effectively managing water resources. Groundwater quantity was estimated using water level fluctuation (WLF), runoff using GIS coupled with curve number and canal water volume using equivalent length factor methods. This study revealed that the contribution of groundwater was more than 52.5%, whereas runoff (45.61%) and canal water (1.89%). Higher amounts of total available water observed in Mihipurwa (305.3 million cubic meter, MCM), Mahsi (211.6 MCM), Chittaura (189.3 MCM) and Nawabganj (184.4 MCM) blocks due to denser vegetation cover and moderate to low curve number values, while Risia (96.5 MCM) had the lowest amounts of available water in juxtaposition with the other blocks due to high industrial draft, higher drop down in the depth of post-monsoon groundwater level and minimal canal water irrigation. The sandy soil predominant in Jarwal had the lowest annual runoff (117.54 mm) while Nawabganj had the highest (359.84 mm) followed by Balha and Huzoorpur due to having a higher elevation over the other blocks. The runoff ratio was found to be larger in Nawabganj (27.74%), followed by Balha (23.06%) and lowest in Mihipurwa (14.89%) followed by Chittaurah (14.91%). Kaisarganj (11.6 MCM) had the highest amount of canal water resources accessible, followed by Mahsi (6.8 MCM) and Huzoorpur (6.1 MCM), while Balha and Nawabganj had the lowest amounts of canal water resources at 0.1 MCM.

Benefits and pitfalls of irrigation timing and water amounts derived from satellite soil moisture

Despite the key role of irrigation in the Earth system, we lack fundamental information regarding the distribution of irrigated fields, irrigation timing and the amount of water utilized. In the past years, the SM_Delta and SM_Inversion approaches have been independently developed to provide estimates of irrigation timing and water amounts based on satellite soil moisture data. The SM_Delta approach retrieves irrigation from variations in soil moisture between an individual pixel and the surrounding rainfed area, while the SM_Inversion approach estimates the total amount of water entering the soil, then irrigation is derived by subtracting precipitation. In this study, we perform a comprehensive assessment of irrigation estimates from the SM_Delta and SM_Inversion algorithms based on Sentinel-1 surface soil moisture retrievals at 1 km resolution. Our analysis focuses on the Ebro basin, an irrigated region in Spain covering 83000 km2, during the period 2017–2019. We assess the ability of the two methods to discriminate irrigated and rainfed pixels, then we quantify the agreement of irrigation timing and water volumes with reference irrigation data. An inter-comparison between estimates from the SM_Delta and SM_Inversion methods is carried out considering both temporal and spatial features, i.e., monthly irrigation peaks and spatial irrigation patterns. Finally, we explore two potential applications of satellite-derived irrigation estimates: attributing irrigation water volumes to specific irrigation systems and to individual crops. We observe that both methods erroneously retrieve irrigation over rainfed pixels, and are therefore not suitable to map irrigated and rainfed fields. However, when auxiliary information on irrigated fields is available, we find a satisfactory agreement between district-scale reference data and satellite-retrieved irrigation, using both the SM_Delta and SM_Inversion approaches (Pearson R equal to 0.67 and 0.71, bias equal to −4.99 and −4.75 mm/15 days, respectively). When aggregated in space or time, the irrigation estimates exhibit coherent temporal dynamics and spatial patterns. For instance, estimates from both SM_Delta and SM_Inversion capture the delayed irrigation that occurred in 2018 due to wetter than usual conditions in spring. However, at the pixel-scale, limited consistency exists between irrigation estimates from the two methods due to different assumptions and parameterizations, e.g., use of constant vs pixel-specific soil water capacity (in the SM_Delta and SM_Inversion, respectively). Overall, the study demonstrates the reliability of irrigation estimates derived from the SM_Delta and SM_Inversion approaches, especially when shifting from small spatial and short temporal scales (pixel level, sub-weekly) to larger and longer scales (district level, seasonal). Hence, satellite-based irrigation estimates could inform water resources managers and basin authorities, as well as serve the modelling community by providing reliable information on the timing and the amounts of water employed at the basin level.

A gravity-induced desalination technology effectively improving the freshwater production efficiency of freeze desalination

Low desalination efficiency and water production efficiency limit the commercial application of freeze desalination (FD) technology. In this study, three freezing temperatures were set to carry out single-stage progressive freezing desalination of brackish water in southern Xinjiang, China. The ice were melted using conventional methods and gravity-induced desalination (GD), and the salt migration law during the icing and melting process was studied. The effect of GD technology on the improvement of the output of frozen desalinated produced water was quantitatively analyzed using scenario simulation. Experimental results showed that salts accumulated towards concentrated water during FD process. The ice total dissolved solids (TDS) increased with decreasing freezing temperature, which was linearly and positively correlated with the raw water TDS. GD efficiency was significantly affected by the salt concentration of ice crystals. In the first stage (the first 450 mL), ice-melt water was salt explosive dissolution, with salt drained mass accounted for more than 85% of the total salt mass. During GD process, exponential decay of ice-melt water TDS (TDSI) was observed with increasing ice-melt water amount. Through the simulation of the two exponential equation scenarios, it was found that Scenario II (mixed water TDSI as the target value) had significantly higher water yield and production rate than Scenario I (TDSI as the target value), with an increase of more than 23%. The algebraic relationship between TDSI of mixed water and the amount of ice-melt water was derived. GD technology can effectively improve the freshwater output efficiency of the FD process, which is manifested by the fact that the ice crystals of the FD process cannot produce freshwater using conventional melting. Scenario II can produce freshwater as high as 69.83% of the total amount of the GD ice-melt water. The GD technology performed increased multiplicatively in WPdv (decrease in water production) and WPRdv (decrease in water production rate) when the TDSI of the mixed water demanded by the user was low. When FD and GD are combined to desalinate salt water, lowering the freezing temperature can significantly increase the freshwater yield, breaking the limitation of freezing temperature for FD. Therefore, an automated, energy-saving freeze desalination-gravity desalination device capable of realizing the collection of the product water according to the users' needs was conceptualized. This study provides new ideas and algorithms for accurately assessing the efficiency of water production in the combined desalination of saltwater by FD and GD.

ئاڵنگارییەکانی ئاسایشی ئاو لە هەرێمی کوردستان

This study investigates two fundamental challenges facing the water security in the Kurdistan Region of Iraq. These challenges are identified as internal and external. Internal challenges are dealt with from two perspectives: one has to do with climate change that leads to decreasing the rainfall and increasing droughts both of which negatively affecting water revenues. The other one is human-related challenges that are associated with water utilisation and water management issues. Such challenges include the excessive use and waste of water as well as water pollution that results in the inability of water revenues (especially surface water such as rivers and lakes) to meet the needs of people in the region. The external challenges, on the other hand, are related to the current water policies pursued by the neighbouring countries of Turkey and Iran. These countries use the water resources located within their borders as a weapon against the Kurdistan Region. About 60% of the region’s water resources comes from Turkey and Iran. Consequently, the strict water policy implemented by these countries has exerted a considerable negative impact on the total amount of water needs in the Kurdistan Region. affected.

Soil moisture regime in lowland forests – quantity and availability of water

Abstract Water is one of the key ecological factors that has a great impact to development and productivity of lowland species such as Quercus robur. This paper deals with water regime influence to site conditions of these species and how actually changeable soil moisture affects Q. robur. Studied area includes a protective embankment built on the river bank in order to eliminate flooding effect, which means that all needs for water these associations provide from rainfalls and groundwater. Water regime was monitored during two critical years (extremely dry and extremely wet) on four soil types – Planosol, Fluvisol and Gleysol that belong to hydromorphic (three experimental plots) and Chernozem which belongs to automorphic soils (three experimental plots), respectively. It was studied the distribution of rainfalls and groundwater during the growing seasons and how it affects total and available water amount in the soil. The main focus should be given to available water, because it is located in capillary pores and plants can utilize it. Bearing in mind rainfalls makes just 15–20% of the total water amount in the soil it is much more significant to evaluate its proportion in available water. Based on obtained results, we can deduce that much more suitable site conditions for Q. robur are present on hydromorphic soils due to much greater proportion of groundwater.

Temperature Reduction as Operando Performance Recovery Procedure for Polymer Electrolyte Membrane Fuel Cells

To efficiently mitigate the reversible performance degradation of polymer electrolyte membrane fuel cells, it is crucial to thoroughly understand recovery effects. In this work, the effect of operando performance recovery by temperature reduction is evaluated. The results reveal that operando reduction in cell temperature from 80 °C to 45 °C yields a performance recovery of 60–70% in the current density range below 1 A cm−2 in a shorter time (1.5 h versus 10.5 h), as opposed to a known and more complex non-operando recovery procedure. Notably, the absolute recovered voltage is directly proportional to the total amount of liquid water produced during the temperature reduction. Thus, the recovery effect is likely attributed to a reorganization/rearrangement of the ionomer due to water condensation. Reduction in the charge transfer and mass transfer resistance is observed after the temperature reduction by electrochemical impedance spectroscopy (EIS) measurement. During non-operando temperature reduction (i.e., open circuit voltage (OCV) hold during recovery instead of load cycling) an even higher recovery efficiency of >80% was achieved.

Bioimpedance analysis of body composition and rest energy expenditure in highly trained cross-country skiers

The body composition monitoring using bioimpedance analysis (BIA) is important in assessing the functional state of athletes in sports. Based on changes of body composition, it is possible to optimize the actual dietary intake, as well as successfully organize the training process. The purpose of this research was to conduct a comparative assessment of BIA parameters and rest energy expenditure (REE) in highly trained cross-country skiers and young non-athletes. Material and methods. The members of the national cross-country skiing team from the Komi Republic and Russian Federation (n=30; age - 22.3±2.7 years) were examined. Practically healthy medical students served as a control group for the present study (n=40; age - 20.2±2.4 years). The participants successively passed the following study steps: assessment of the body composition by BIA (ACCUNIQ BC380), REE determination by indirect non-fasting calorimetry and calculation technique. Results. The parameters of total body water, fat-free mass, lean tissue and body cell mass were higher in contrast to the fat mass percentage in the athletes (р<0.001). The calculated REE was lower than measured REE among all the participants. At the same time, the REE calculated by the Ketch-McArdle formula significantly differed between the groups, while no differences were found between the REE calculated by the Harris-Benedict prediction equation. The measured REE were significantly higher by 16% (p<0.001) i n athletes compared to those in the control group. Conclusion. The body composition of athletes was distinguished by a significantly higher amounts of total body water, fat-free mass, skeletal muscle, active cell mass, and lower percentage of fat mass compared to healthy untrained individuals. The results obtained among athletes coincided with the idea that the magnitude of REE is determined by the mass of metabolically active tissues and to a lesser extent depends on the fat mass. BIA results can be used to monitor athletes' body composition during the training process.

The Influence of Sprinkler and Drip Irrigation on the Incidence and Severity of Bacterial Disease in Onions Grown in Northeast California

Overhead sprinkler irrigation and its effect on leaf wetness are often referenced as a key factor for bacterial disease spread in onions grown in arid climates. A study was conducted in 2021 and 2022 in Tulelake, California, to compare the incidence and severity of bacterial disease under sprinkler and drip irrigation. The experiment was a split-plot randomized complete block design with drip and solid-set sprinkler irrigation as the main plot treatments and inoculation and no inoculation with plant-pathogenic bacteria as the split-plot treatments. The entire study area was irrigated with solid-set sprinklers from planting until the five-leaf stage to facilitate uniform onion germination and chemigation of herbicides for weed control. After the five-leaf stage, irrigation treatments were imposed for the remainder of the growing season. Total irrigation water amount and irrigation frequency were similar for both irrigation methods. Foliar disease severity and the incidence of bulb rot were 170 and 186% higher, respectively, for solid-set sprinkler compared with drip irrigation. Leaf wetness within the plant canopy during onion bulbing was on average 36% higher in the solid-set sprinkler compared with drip irrigation treatment, whereas relative humidity and temperature were similar between irrigation methods. Drip irrigation maintained lower soil water tension and increased average bulb size by 9% compared with solid-set sprinkler irrigation. This study confirms historical observations that overhead irrigation can extend leaf wetness and increase bacterial disease in onions in arid production areas and highlights the potential benefits of the adoption of drip irrigation.

Determinants of the accuracy of using carbon isotopes in estimating water use efficiency of selected cereal and legume crops: A global perspective

AbstractField assessments of crop water use efficiency (WUE) are resource‐consuming since they require simultaneous assessment of the total amount of water assimilated by crops for biomass and/or grain production. Alternative methods exist, such as estimating the carbon isotopic ratio (13C/12C) of the crop's leaf, aboveground biomass, or grain samples. There is limited information on the determinants of the accuracy of carbon isotopes in estimating water use efficiency between crop types and environments. Therefore, this study aimed to evaluate the extent to which the estimation of the 13C/12C ratio in crop parts constitutes an accurate proxy of WUE, globally. Data on observed WUE (WUEobs) were collated involving 518 experiments conducted worldwide on major cereals and legumes and compared with WUE estimates (WUEest) from carbon isotopes. The mean WUEobs among all experiments was 3.4 g L−1 and the mean absolute error (MAE) was 0.5 g L−1 or 14.7% of WUEobs, corresponding to accurate predictions at p &lt; 0.05. However, the percentage mean absolute error of observed water use efficiency (%MAE) estimated from grains was 3.6 ± 11.5%, which was lower than the %MAE from aboveground biomass collected at harvest (3 ± 22.8%). In addition, the %MAE increased from 1.1 ± 5.1% for soybean, 1.6 ± 7.2% for maize, 1.2 ± 8.6% for rice, 1.8 ± 12.1% for groundnut, 2.1 ± 14.3% for cowpea, 2.3 ± 16.2% for bush bean, 1.8 ± 19.9% for wheat, 2.2 ± 21.4% for barley to 6.3 ± 39.3% for oat, with only the latter corresponding to significant errors. WUEest were, in all cases, unbiased but slightly overestimated from 0.8% (maize) to 15.4% (oat). The accuracy in estimating WUE significantly decreased with the increase in soil clay content, with sand, showing a positive correlation of 0.3 with %MAE, but negatively correlated with the silt content (r = −0.4). Furthermore, a multivariate analysis pointed out a tendency for prediction errors and bias to increase with the decrease in WUEobs and air temperature. Using carbon isotopes for estimating crop WUE thus appeared reliable for all crops and world environments, provided grain samples are considered. The technique tended to perform better under high WUE conditions, such as those generally found in maize and soybean cropping systems. The identified factors that affect the accuracy of using carbon isotopes in measuring WUE provide valuable insights for water resource management and sustainable crop production. These findings contribute to the ongoing discourse on water conservation strategies in agriculture, offering a basis for decision‐making in crop improvement programs. Implementing the recommended practices from this study can potentially improve yield gains and promote resilient and sustainable agricultural systems in the changing environmental circumstances. Further research should investigate the mechanisms that cause low accuracy of the isotopic technique using aboveground biomass and under arid and cool environments.

IoT-enable smart agriculture using multiple sensors for sprinkle irrigation systems

The Internet of Things (IoT) has experienced considerable expansion and development in recent years, offering a multitude of prospects for technological progress in the agricultural sector, with the aim of improving efficiency and providing help to farmers on a global scale. This paper outlines the conceptualization and development of an smart sprinkle irrigation system that incorporates the Internet of Things (IoT) technology, leveraging the ESP32 platform. The aim of this study is to develop a smart irrigation-based internet of things utilizing multiple sensors for sprinkle irrigation system. This will be achieved by integrating several sensors to monitor and control the irrigation process. The facilitation of communication between the ESP32 device and the Blynk application simplifies the acquisition of irrigation data, initiation of plant watering, deactivation of the automated watering functionality, and generation of graphical representations derived from sensor measurements. The irrigation system that has been created encompasses three distinct ways, particularly manual, semi-automatic, and automatic. The manual irrigation method enables users to directly administer irrigation, but the semi-automatic method necessitates users to select the timing and length of watering. The automated approach employs irrigation systems that are capable of responding to soil moisture levels, triggering the activation of the pump when the moisture content decreases beyond a predetermined threshold. The device is equipped with a pH sensor that enables the monitoring of soil pH values, a critical factor in facilitating optimal plant growth and development. The system has the capability to present the rate at which water flows and the total amount of water utilized in a singular irrigation event, as well as to aggregate the water consumption across many irrigation instances. In general, the experiments demonstrate the satisfactory performance of the three irrigation systems, including the capability to manually initiate the pump.

Cotton irrigation regime under the mole irrigation method in the south of Russia

Studies on developing optimal soil water regimes under mole irrigation of cotton compared with sprinkling and drip irrigation were conducted in 2023 on light-chestnut soils of southern Russia. As a result, it was found that under mole irrigation, with increasing the pre-watering threshold of soil moisture from 70-70-65 to 80-80-75 % of the lowest water holding capacity (LWC) irrigation rates decreased from 250...290 to 170...210 m3/ha and the number of irrigations and irrigation rate increased from 4 to 7 units and from 1040 to 1270 m3/ha. A comparison of irrigation methods showed that under mole irrigation, in comparison with drip irrigation, irrigation rates increased by 7.4. 13.3 %, and the number of irrigations per season and irrigation rate decreased by 1...2 units and 11.2...12.6 %, respectively. Compared to sprinkling, irrigation rates and total amount of water decreased by 45.2...46.3 and 28.8...34.5 %, respectively, and the number of irrigations increased by 1 unit. It was also found that maintaining a moisture availability level of 75-75-70 % LWC created optimal conditions in cotton crops, which, combined with mineral fertilizer application with doses N140P60K45, allowed the highest cotton yield under mole irrigation of 3.18 t/ha. When sprinkling on a similar option, it decreased by 0.21 t/ha, and at drip irrigation, it increased by 0.13 t/ha.

Estimation of Crop Water Requirement of Sweet corn crop using CROPWAT 8.0 model

Most of the crops are watered through traditional methods of irrigation, which leads to wastage of water. The Crop Water Requirement (CWR) is necessary to design the irrigation system, which is the total quantity of water required for the crop from sowing to harvest.Optimization of water applied to the crop is essential as the yields of the crop are adversely affected either by excess or deficit water supply. CROPWAT 8.0 requires meteorological data as input such as maximum and minimum temperatures, wind speed, relative humidity, and sunshine hours. The soil and crop data were also given as input for calculating the CWR of sweet corn. The meteorological data of the past ten years was collected from the meteorological observatory, which is located at Agricultural College Farm, Bapatla. The average values of the above-said data were calculated for ten years (2012-2021) to estimate the crop water requirement using CROPWAT 8.0. The crop water requirement was estimated as 332 mm using the CROPWAT 8.0 model. It was found to be minimal in the initial stages (15.60 mm/dec) and found to be maximum in the middle stages (64.80 mm/dec), and again at harvesting stage, it started declining (16.70 mm/dec). CROPWAT 8.0 model gives more accurate amount of water needed for the crop, which in turn helps the crop growers to design the appropriate irrigation scheduling.

Stream Flow Management and Institutions: Studying Water Quality and Aquatic Ecosystems in Dry Seasons

Stream flow management during the dry season involves balancing human water needs with the environmental requirements of the river. The allocation of stream water flow is determined by considering 10-year frequency low flow as the total available water amount, with instream flow adopted to consider the flow requirements of the river environment. However, conflicts arise over water rights between human users and the river environment during water scarcity. This study conducted an empirical-based analysis of minimum flow for river environments, focusing on water quality and aquatic ecosystems. Additionally, the perceptions of stakeholders of securing and using stream flow were investigated through a questionnaire. The outcomes of this study can contribute to enhancing technical methods for calculating instream flow and improving systems for managing river water during dry seasons.

The Investigation of the Amount of Blue Crab Production Regarding Other Crustaceans and Molluscs’ Farming in Türkiye

The aim of this study was to examine the factors affecting the catch rate of crustaceans and molluscs and to determine the effect of factors affecting the catch rate of blue crab. In this study, data of 14 variables (octopus, lobster, black mussel, etc.), total crustacean and mollusc content and total freshwater fish were examined from the crustaceans and molluscs caught from the TUIK website between 2012-2021. In addition to the comparison of these amounts, variables such as renewable water resources per capita, renewable surface water, total water withdrawal per capita, and water withdrawal for aquaculture were included in the study. Finally, the study was concluded by comparing seafood, aquaculture and freshwater products. The relationships between blue crab and other crustaceans and molluscs, water related statistics, aquaculture statistics were examined by regression analysis. As a result of the analyzes made, other creatures that affect the hunting rates of the blue crab; It was concluded that there is a category of jumbo shrimp, cuttlefish and other. At the same time, it was concluded that the total amount of fresh water and the amount of freshwater products affect the catch rate of the blue crab.