Furrow Length Research Articles

First person – Bipasha Dey

ABSTRACT First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Bipasha Dey is first author on ‘DE-cadherin and Myosin II balance regulates furrow length for onset of polygon shape in syncytial Drosophila embryos’, published in JCS. Bipasha has recently completed her PhD and is continuing to work in in the lab of Dr Richa Rikhy at Indian Institute of Science Education and Research, Maharashtra, India, where she is broadly interested in studying how mechanical forces in cells and tissues guide morphogenesis.

DE-cadherin and Myosin II balance regulates furrow length for onset of polygon shape in syncytial Drosophila embryos.

Cell shape morphogenesis, from spherical to polygonal, occurs in epithelial cell formation in metazoan embryogenesis. In syncytial Drosophila embryos, the plasma membrane incompletely surrounds each nucleus and is organized as a polygonal epithelial-like array. Each cortical syncytial division cycle shows a circular to polygonal plasma membrane transition along with furrow extension between adjacent nuclei from interphase to metaphase. In this study, we assess the relative contribution of DE-cadherin (also known as Shotgun) and Myosin II (comprising Zipper and Spaghetti squash in flies) at the furrow to polygonal shape transition. We show that polygonality initiates during each cortical syncytial division cycle when the furrow extends from 4.75 to 5.75 μm. Polygon plasma membrane organization correlates with increased junctional tension, increased DE-cadherin and decreased Myosin II mobility. DE-cadherin regulates furrow length and polygonality. Decreased Myosin II activity allows for polygonality to occur at a lower length than controls. Increased Myosin II activity leads to loss of lateral furrow formation and complete disruption of the polygonal shape transition. Our studies show that DE-cadherin-Myosin II balance regulates an optimal lateral membrane length during each syncytial cycle for polygonal shape transition.This article has an associated First Person interview with the first author of the paper.

Effect of micro-dams on water flow characteristics in furrow irrigation

Surface irrigation, particularly furrow irrigation, is the most common method of water application into agricultural lands. Despite all its advantages, furrow irrigation has some demerits, such as a potential large volume of runoff losses. In this research, an approach was proposed to reduce runoff losses and to improve water flow characteristics by creating micro-dams, barriers inside the irrigated furrows. To control water flow and increase infiltration into the soil, experimental micro-dams were created at distances of 10 and 20 m, with a height of 5 cm. Field experiments were conducted at the research farm of the College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran in summer of 2018. Two erosive inflow rates (0.6 and 0.9 L/s) were considered. Furrow length and spacing were 100 and 0.75 m, respectively. Results indicated that micro-dams increased the advance time, leading to increased infiltration. Micro-dams also increased the recession time, due to the increase in overland water volume. Moreover, results showed that in treatments with micro-dams, runoff was reduced by up to 45.3% in comparison to the control treatment. The change in furrow cross-sectional area during the irrigation event was also reduced. Micro-dams showed a great potential to reduce irrigation runoff losses, and should be considered as a management practice aiming at water and soil conservation.

THE CHANGES OF COTTON SEED-LINT YIELD IN PARTS OF FURROW LENGTH UNDER DIFFERENT IRRIGATION SCHEDULING

The paper indicates the results of furrow irrigation technology along parts of furrow and its impact on seed-lint yield and boll weight of upland cotton varieties (Gossypium hirsutum L.) Sultan, UzPITI-103, C-8295 and Kelajak. The research was conducted in the condition of old irrigated typical sierozem soils with mechanical composition of silt loam in Tashkent province, at the Central Experimental Station of Uzbekistan’s Cotton Breeding, Seed Production and Agrotechnologies Research Institute in 2015 to 2019. In research, cutoff flow furrow irrigation was applied where irrigating with inflow rate of 0.40 to 0.42 l s-1 in the beginning of irrigation in three in four part of furrow, then decreasing it till 0.20 to 0.22 l s-1, the inflow rate decreased twice 0.12 to 0.15 l s -1 by reaching water the end of furrow which ensured wetting the root zone layer of soil smoothly along the furrow length. Irrigation scheduling 70-75-65% Fc was optimal for cotton varieties of Sultan and C-8295, where the irrigation scheduling 70-70-60% Fc for UzPITI-103 variety and irrigation scheduling 65-65-60% Fc for Kelajak variety was optimal. In all abovementioned varieties the highest seed-lint yield and boll weight were obtained in the furrow length of 30 to 70 m. The highest seed-lint yield of cotton (4.71 t ha-1 Sultan variety, 4.48 t ha-1 UzPITI-103 variety, 4.27 t ha-1 C-8295 variety, 3.93 t ha-1 Kelajak variety) was obtained in the part of furrow length 30 to 70 m in comparison with the furrow length 0 to 30 m and 70 to 100 m the seed-lint yield was decreased by 0.17 t ha-1 and 0.39 t ha-1 in Sultan, 0.13 t ha-1 and 0.16 t ha-1 in UzPITI-103, 0.10 t ha-1 and 0.16 t ha-1 in C-8295, 0.14 t ha-1 and 0.21 t ha-1 in Kelajak varieties. According to research results, the furrow length must not exceed 70 m.

Extensive comparison of various infiltration estimation methods for furrow irrigation under different field conditions

Accurate estimation of infiltration coefficients in surface irrigation is essential for proper design, reducing water losses, preventing erosion and increasing water use efficiency. This study was conducted to evaluate various methods for estimating the coefficients of infiltration equations. We have selected 17 different methods with better performance based on previous studies, out of many methods which have been introduced for infiltration estimation. In order to compare the methods, 50 furrow data sets were selected which are different based on field and irrigation conditions. The results indicated that the performance of the infiltration estimation methods is variable because of various field conditions and required data requirements. Amongst the two-point methods, the Elliott and Walker method, with an average Relative Error (RE) of 16 %, the Vatankhah et al. method (RE = 16 %) between one-point methods and the Multilevel Calibration method (RE = 18 %) as compared with other computer-based models were concluded as the most accurate methods for estimating infiltration coefficients. The sensitivity analyses indicated that variations in relative error for estimating infiltration parameters are a function of soil texture, furrow length, inflow discharge and field slope.

EVALUATION OF PARTIAL ROOT ZONE DRYING IRRIGATION UNDER GATED PIPE FOR CORN CROP

In recent time, Egypt is suffering from the scarcity of fresh water. In addition, Egypt is one of the event states under the water poverty line, who is identified as less than 1000 m3 per capita per year due to the existence of dry climatic conditions in most parts of the country and limited available water resources, therefore optimization and saving of water consumption have vital importance. The main goal of this research is to study the effect of Partial Root zone Drying (PRD) on corn yield, water distribution efficiency and water use efficiency compared with conventional irrigation (CI).Field experiment was conducted during summer season of 2017 in the Agricultural research station, Etay El-Baroud, El-Behera Governorate (Etay-El-Baroud region is 6m above sea level, 30˚ 88 / N and 30˚ 66 / E).Corn plants were planted under different irrigation regimes which were Alternate Partial Root zone Drying (APRD),Fixed Partial Root zone Drying (FPRD),and Conventional Irrigation (CI) comparing with control irrigation. The irrigation regimes were carried out under two levels of land leveling (0.05% - 0.1%), and three levels of water cutting times. The experimental treatments were irrigated by 152mm diameter of PVC gated pipes system. The results indicated that, the APRD treatment achieved the highest value of corn production (7.85Mg ha-1) when the applied water was reached to the end of furrow plus 5 minutes storage (Q3) under furrow slope of 0.1% and improving water use efficiency (WUE) when applied water was reached 5m before the end of furrow length (Q2) by 1.73 kg m-3 under furrow slope of 0.1%. Also, the APRD regime saved 37.16% of applied water under Q2 and furrow slope of 0.1%.

Definition of Fuel and Lubricant Consumption Rates and Production of Tractor Units As Part of John Deere Tractors

Tractors are mainly applied in agriculture. The share of import in the structure of tractor machinery market is constantly growing. One of the information sources for the optimization of the machine and tractor fleet and the development of standards to satisfy the needs of typical farms in tractors and agricultural machines for crop production are the performance standards of machinery and fuel consumption. The recommended norms of fuel production and consumption imply the rational use of shift time, optimal composition of machine-tractor units and effective operation modes of tractors and self-travelling agricultural machines. In recent years, many tractors and agricultural machines of foreign companies, including John Deere, are working in the fields of Trans-Urals, Siberia and Russia as a whole. The standards of production and consumption of fuels and lubricants for these agro-climatic conditions are not available for all machine-tractor units. Therefore, it is becoming ever more relevant for agricultural producers to develop such. The studies to establish fuel consumption standards and performance rates of machine-tractor units as part of John Deere tractors were carried out in the fields of agricultural enterprises of the Tyumen Region. The paper presents the results of the study. For example, the productivity of a tractor for a field located at a distance of 5–6 km and an average length of furrow of 1300 m can be in the range of 5.8–6.0 ha/h. Taking into account natural and climatic conditions and different physical and mechanical composition of soil, as well as configuration of fields and length of furrows during processing, the data on the consumption of basic lubricants were obtained. Recommendations on the use of consumption rates for fuels and lubricants of modern tractors in various technological operations in agriculture will greatly facilitate planning and calculation of operating costs of machine-tractor units. The paper considers recommendations on the use of correction factors to the nominal range of fuel consumption depending on soil type for John Deere tractors of the 9th series on the example of disk tillage. Software for economic evaluation of agricultural machinery as part of agricultural technology was developed.

Optimization of furrow irrigation performance of sugarcane fields based on inflow and geometric parameters using WinSRFR in Southwest of Iran

Accurate design, suitable management and optimization of irrigation design parameters play an important role in increasing the performance of furrow irrigation. The main objective of this study was to optimize the performance of furrow irrigation using WinSRFR in the fields of Salman Farsi Agro Industry sugarcane, located in the southwest of Iran. For this purpose, field experiments were conducted under nine blocked-ended furrows with the length of 250 m, the top width of 1.83 m and slope of 0.04 % and in three inflow treatments (1.0, 1.5 and 2.0 L/s) with three repetitions. The WinSRFR software was employed to optimize the combination of irrigation parameters such as inflow rate, cut-off time and field geometry. Objective function (OF) including application efficiency, distribution uniformity and deep percolation was also employed to optimize the performance. The results showed that using 1.0 L/s inflow rate could increase OF by 35.99 % which was the best performance compared to 1.5 and 2.0 l/s. Changing furrow length from 250 m to 200 m showed that OF value increased by 39.8.% ; however, changing it to 300 m, OF decreased by 7.7 %. In addition, changing slope from 0.04 to 0.03 % decreased OF by 0.9.%, while changing it to 0.05 % OF was improved by 1 %. On the other hand, changing the inflow and cut-off time, field length and combinations of them led to the increased OF by 25, 8.39 and 31 %, respectively. Finally, to obtain the maximum performance in sugarcane fields, inflow rate of 3 L/s and cut-off time of 379.5 min were suggested.

Surge flow Performance for Furrow Irrigation under Upper Egypt Conditions

The current study was conducted at The Experimental Farm, Fac. of Agric., Al-Azhar Univ., Assuit, Egypt (27° 12- 16.67= N latitude, 31° 09- 36.86= E longitude and at 51 m altitude) during the winter season of 2018 (September to December). The research work aimed to assess the performance of surge irrigation compared to the continuous one by measuring the advance rate of the wetting front, inflow/ outflow rates, distribution uniformity, application efficiency, suitable furrow length and surge numbers. Surge flow irrigation leads to a decrease in advance time compared to continuous flow. The reduction percentages in advance and recession time are more pronounced under low discharge rate and long furrow length. Surge flow irrigation used less amounts of water than continuous one. Surge flow could save almost one third of the applied water by continuous flow especially into long furrow with 5 surges of medium discharge rate. The larger discharge coupled with large furrow resulted in the maximum water saving of about 28% among all the other combinations. For all possible combinations, the volume ratio remained less than one indicating that less total water is required to complete the advance phase in surged irrigation compared to continuous one. Surge flow showed higher application efficiency than that of continuous one. The higher application efficiency (83%) was observed under 5 surges flow into 100 m furrow length with 1.2 L/S discharge rate. Water losses by deep percolation were more pronounced in short furrow length than that of long one and they were minimized by surge flow. Surge flow realized higher distribution uniformity (DU) than that of continuous one.

EVALUATION OF PARTIAL ROOT ZONE DRYING IRRIGATION UNDER GATED PIPES SYSTEM FOR CORN CROP

In recent time, Egypt is suffering from the scarcity of fresh water. In addition, Egypt is one of the event states under the water poverty line, who is identified as less than 1000 m3 per capita per year due to the existence of dry climatic conditions in most parts of the country and limited available water resources, therefore optimization and saving of water consumption have vital importance. The main goal of this research is to study the effect of Partial Root zone Drying (PRD) on corn yield, water distribution efficiency and water use efficiency compared with conventional irrigation (CI).Field experiment was conducted during summer season of 2017 in the Agricultural research station, Etay El-Baroud, El-Behera Governorate (Etay-El-Baroud region is 6m above sea level, 30˚ 88 / N and 30˚ 66 / E).Corn plants were planted under different irrigation regimes which were Alternate Partial Root zone Drying (APRD),Fixed Partial Root zone Drying (FPRD),and Conventional Irrigation (CI) comparing with control irrigation. The irrigation regimes were carried out under two levels of land leveling (0.05% - 0.1%), and three levels of water cutting times. The experimental treatments were irrigated by 152mm diameter of PVC gated pipes system. The results indicated that, the APRD treatment achieved the highest value of corn production (7.85Mg ha-1) when the applied water was reached to the end of furrow plus 5 minutes storage (Q3) under furrow slope of 0.1% and improving water use efficiency (WUE) when applied water was reached 5m before the end of furrow length (Q2) by 1.73 kg m-3 under furrow slope of 0.1%. Also, the APRD regime saved 37.16% of applied water under Q2 and furrow slope of 0.1%.

SOIL CONSERVATION SERVICE (SCS) AS A TOOL FOR PROPER DESIGN OF COTTON-FURROW IRRIGATION IN CLAY SOIL

Flood surface irrigation is the main watering system in Egypt and worldwide. Proper design of such system is the milestone for up-grading and improving surface irrigation as for other irrigation systems. In this regard, the said Soil Conservation Service (S.C.S) developed by the soil reclamation bureau, USA was the used tool in the evaluating and assessment of the implemented or the practiced parameters, which executed in cotton furrow irrigation system design in the Northern Nile Delta area. The field trial was conducted during the two growing summer cotton seasons 2017 and 2018 at the experimental farm of Sakha Agricultural Research Station, North Nile Delta area. Combined effects of different land leveling (i.e. traditional, precession (dead level =zero level), 0.05 and 0.10%) and irrigation inflow rates. (2.0, 2.7 and 3.3 Lps/m widths) were used. The stated treatments were implemented at fixed furrow length and width of 40.0 m and 0.75 m. respectively. The comparing elements between design created by SCS and the actual practiced measures were: furrow inflow rate (Lps/m), irrigation time (min.), advance time (min.), recession time (min.), opportunity time (min.), depth applied (mm), deep percolation (mm), deep percolation ratio and irrigation application efficiency (IAE).Moreover, extensive economic evaluation was done regarding seed cotton yield, total return, benefit/cost ratio and the specific cost. Analysis of obtained data revealed that application efficiency is acceptable for inflow rate at 2.0 Lps/m width along with precession land leveling of 0.05 or 0.10%, providing the importance of using SCS in design furrow irrigation system in the clayey soils at North Nile Delta. Moreover, maximum water well land productivity were observed under the stated treatment (2.0 Lps/m width with 0.05 or 0.10% land leveling)

Suitable inflow rate and furrow length for simplified surge flow irrigation

In the arid lands covering Uzbekistan, furrow irrigation with low application efficiency is still widely used due to a lack of funds and shortage of labor. To save water and prevent secondary salinization caused by excessive irrigation, it is important to adopt low-cost and easy water-saving irrigation methods. Onishi et al. (2017) proposed simplified surge flow (SF) irrigation that does not require expensive equipment and merely divides the water supply into two phases at 1-day intervals. This study investigated the suitable inflow rate and furrow length of simplified SF to improve water application efficiency in Uzbekistan. Five experimental plots (total area of 2,250 m2, with 25 furrows) were set up, and the inflow rates for two plots were 5 Ls−1 (F5.0) and that for the others were 1.7 Ls−1 (F1.7). The conventional irrigation method (F5.0C and F1.7C) and simplified SF (F5.0S and F1.7S) were applied to cases of furrow length of 100 m under each inflow rate. In addition, simplified SF was applied on a 50-m furrow at F1.7 (F1.7S-50). In the first irrigation using simplified SF, water was supplied from the start point of the furrow (0 m) for half of the furrow length (50 m, 25 m). In the second irrigation, water was supplied from the start point to the end of the furrow (100 m, 50 m). The application efficiency in F1.7S and F1.7S-50 was higher than that in F1.7C and F1.7C-50, and the highest was in F1.7S-50. The water supply duration was shorter in F5.0S, but the total volume of supplied water was larger than that of F1.7C. These results indicate that shortening furrow length might be an effective way to save water using simplified SF with a low inflow rate, and in contrast, that it is necessary to extend furrow length with a high inflow rate.

Improvement of Soil and Water Productivity for Sugar Beet under Salt Affected Soils at North Nile Delta, Egypt

A field trial was conducted during the two consecutive growing seasons of 2016/17 and 2017/18 at Sakha Agricultural Research Station Farm, Kafr El-Sheikh Governorate. The aim of this current study was to evaluate the effect of four irrigations treatments; cut-off at 100 (I1, traditional practice), 90%(I2), 80% (I3) and 70% (I4) from furrow length and five fertilization treatments; F1 (90 Kg N Fed.-1), F2 (67.5 kg N+3 ton compost fed.-1), F3 (45 kg N+5 ton compost fed.-1), F4 (22.5 Kg N+7 ton compost fed-1) and F5 (10 ton compost fed.-1) (ha =2.4 fed) on some water parameters, some soil properties and yield of sugar beet. The experiments were designed as spilt plot with three replications. The main plots were occupied by cut-off irrigation, while subplots were devoted to fertilization rates. The main results can be summarized as follows: The highest values of applied water (3678 and 3562 m3 fed-1); water consumptive use (2381 and 2210 m3 fed-1) and water stored (2525 and 2456 m3 fed-1) were recorded under I1 (local farmers practice) in the 1st and 2nd seasons, respectively. On the other hand, the lowest values of applied water (3168 and 3094 m3 fed.-1); water consumptive use (2218 and 2062 m3 fed-1) and water stored (2325 and 2335 m3 fed-1) were recorded with I4 in the 1st and 2nd seasons, respectively. The highest values of water saving was recorded under I4 as average of the two growing seasons (12.14 cm and 11.14 cm, respectively) which saved about 100*106 m3 water in sugar beet fields at the national level (200*103 fed) comparing with check treatment (I1). The highest values of irrigation application and consumptive use efficiencies in both seasons were achieved under irrigation treatment I4 but the lowest values were recorded under irrigation treatment I1 in the two studied seasons. Concerning to water productivity ( ) and productivity of irrigation water (PIW), the highest values of (14.09 and 16.74 Kg m-3) and PIW (9.70 and 11.61 kgm-3) were recorded under I3 in the first and second seasons, respectively. On the other hand, the lowest values of (12.16 and 14.99 kgm-3) and IPW (7.88 and 9.30 Kgm-3) were recorded with I1 in both seasons, respectively. Concerning to the role of fertilization in and PIW, F2 treatment achieved the highest values of (14.38 and 17.38 kg m-3) and PIW (9.99 and 11.23 kg m-3), while F4 treatment gave the lowest values of both parameters in both seasons, respectively The soil ECe, SAR and ESP as mean values of both seasons were affected by irrigation cut-off and fertilization treatments. The highest reduction of ECe, SAR and ESP was induced by F5 under I1, while the lowest reduction was recorded with F1 and I4. The highest root yields (18.78 and 20.61 ton fed-1) were achieved with I3, while F5 was the best fertilization treatment (15.76 and 18.13 ton root fed.-1) in both seasons, respectively. So, the highest significant effects of cut- off and fertilization treatments on sugar beet root, shoot and sugar yields in both growing seasons were achieved with I3 and F5. Also, there were high significant effects on such parameters due to the interactions between different treatments.

A Method for Determining the Discharge of Closed-End Furrow Irrigation Based on the Representative Value of Manning’s Roughness and Field Mean Infiltration Parameters Estimated Using the PTF at Regional Scale

Infiltration parameters and Manning’s roughness are essential input parameters for surface irrigation simulation models. Multiple points of infiltration experiments require time-consuming, costly data collection and problematic calculations of field mean infiltration parameters. This study estimated the field mean infiltration parameters and Manning’s roughness values on a regional scale, on the basis of closed-end furrow irrigation experiments conducted at 45 experimental sites on the Guanzhong plain, and evaluated the influence of Manning’s roughness on advance trajectory and performance indicators of closed-end furrow irrigation. Then, we present a functional normalization of the Kostiakov equation and pedotransfer function (PTF) to estimate the normalization factors. The proposed method can be used to estimate the field mean infiltration parameters using PTF and the represented Manning’s roughness to determine the optimal discharge of closed-end furrow irrigation. The results revealed that the advance trajectory and performance of closed-end furrow irrigation was not sensitive to variations of Manning’s roughness, which can be adopted as a representative value (i.e., 0.075) of the maize field. The normalization method was proven to be feasible for the Kostiakov equation, and the PTF reliably estimated the normalization factors. Last, the optimized values of the inflow discharge were determined using the proposed method, with various combinations of furrow lengths and bottom slopes in the study area, and also compared with the inflow discharge determined based on infiltration parameters and Manning’s roughness, which were inversed by SIPAR_ID. The results indicated that the inflow discharge values obtained through using the two methods were approximately equal, proving that the proposed method was reliable and easy to use in practice.

Assessment of the pure sowing of different legumes and in mixtures with grass on productivity and damage level by Sitona spp. and Otiorrhynchus ligustici (LINNAEUS, 1758) (Coleoptera: Curculionidae)

Abstract This work examined the impact on productivity of the cultivation system of perennial legumes such as sainfoin (Onobrychis viciifolia), bird’s-foot trefoil (Lotus corniculatus) and alfalfa (Medicago sativa), grown pure and in binary mixtures with cocksfoot and on damage caused by root pests of Sitona spp. and Otiorrhynchus ligustici. It was found that the productivities of aboveground and root biomasses in binary mixtures were significantly higher compared to the corresponding legume monocultures on average by 30.7 and 39.7% respectively in mixtures with sainfoin, by 15.0 and 73.1% in mixtures with bird’s-foot trefoil, and by 18.7 and 49.6% in mixtures with alfalfa. The weight of dry aboveground biomass in the pure leguminous crops slightly exceeded that of the corresponding leguminous components in the mixtures, whereas the productivity of cereal plants in mixed crops was significantly lower compared to the pure cocksfoot on average by 38.5, 47.0 and 51.7% in mixtures of sainfoin, bird’s-foot trefoil and alfalfa respectively. A similar tendency was observed with regard to dry root biomass. Damage to nodules by Sitona larvae in mixtures decreased significantly: on average by 33.5% (sainfoin + cocksfoot), by 50.3% (bird’s-foot trefoil + cocksfoot) and by 55.6% (alfalfa + cocksfoot) compared to pure grown legumes. The damage caused by Otiorrhynchus ligustici, as expressed by the length of gnawed furrows, in the mixtures with sainfoin, bird’s-foot trefoil and alfalfa decreased considerably - by 12.5, 77.8 and 59.5%, respectively - compared to the pure crops. The damage caused by the аlfalfa snout beetle had the most significant negative effect on aboveground and root biomass productivities. Mixed cultivation systems of forage crops are an economically and ecologically sustainable method of insect pest control.

Estimation of Manning roughness coefficient for vegetated furrows

Manning’s roughness coefficient is one of the most important parameters in the design and evaluation of surface irrigation. In this study, Manning’s roughness coefficient was evaluated under two different inflow discharges (i.e., 0.29 and 0.44 L s− 1) on vegetated furrow irrigation during maize growing season. In addition, the accuracy of multilevel optimization and SIPAR-ID methods was evaluated for the estimation of Manning’s roughness coefficient and infiltration equation parameters in vegetated furrows. Spacing, length, and longitudinal slope of experimental furrows were 0.75 m, 110 m, and 1.2%, respectively. Values of the Manning’s roughness coefficient in the vegetated furrows increased as compared to its recommended values in bare furrows. On the contrary, inflow discharge had a weak inverse impact on Manning’s roughness coefficient. Roughness coefficient was the highest at downstream section (end) of the experimental furrow and its value at the middle section was higher than that of upstream section. The results also indicated that the multilevel optimization method had a good performance with average relative error (RE) about 5% for both discharges and SIPAR-ID method had an approximately proper estimation with relative error ranging from 4.6 to 15% in estimating Manning’s roughness coefficient for all irrigation events. To estimate the infiltrated volume of water into soil, the multilevel optimization method had a very good performance (RE = − 1.65 to 2.81%).

ASSESSMENT OF THE BOROZDKOVY ELEMENTS OF WATERING OF SUNFLOWER ON THE CISCAUCASIAN CARBONATE CHERNOZEM OF THE STEPPE ZONE OF KBR

Basic elements of superficial watering on furrows in a steppe zone of the Central part of the North Caucasus on the carbonate chernozem of long irrigation are studied. Parameters of dependence of field norm on length of an irrigation furrow and a specific stream of water, productivity on watering for a shift of a polivalshchik, energy consumption at the studied elements of borozdkovy watering and frequency rate of irrigation are determined. It is revealed that at biases 0,025-0,030 speed of current of water don’t lead to manifestation of washout of the soil to negative level. The maximum irrigation norm about 1100-1300 m3 of hectare are reached when watering on the furrow length 200-300 m the productivity of sunflower is in direct dependence on irrigating norm and varies from 22 to 32 c/hectare. The maximum efficiency of sunflower is formed in a head piece of the sector of the irrigated site.

MAXIMIZING OF SURFACE IRRIGATION PERFORMANCE ON GROWTH AND PRODUCTION OF COWPEA IN CLAY SOIL

Alternate furrow irrigation (AFI) is gaining interest as a mean of saving water while minimizing loss in crop production. Field experiment was conducted in the Experimental Farm, Faculty of Agriculture, Kafrelsheikh University, Egypt, during growing season of 2016-2017. The present work included the following: Irrigation systems (Furrow surface irrigation and surface drip irrigation (SDI)). However, different techniques had been investigated with surface irrigation (alternative furrow (AFI) and conventional furrow irrigation (CFI) with a furrow length of 20, 30 and 40 m. The experiment was designed as split plot with three replications, where irrigation systems used as the main plot and furrow length as sub-plot. The ranges of mean cowpea yield gained from irrigation system were 932.33, 910.52 and 1179.52 kg/fed for CFI, AFI and SDI respectively. The effect of furrow length and their interaction with irrigation system on yield were non-significant but the irrigation system has significant effect on yield (P<0.01). The maximum and minimum yield was obtained at length of 20 m for SDI and length of 40 m for AFI, which were 34.37 kg and 25.26 kg, respectively. The effect of irrigation system on the water use efficiency (WUE) was significant (p<0.01). The average WUE was decreased from 11.57 to 8.10 kg/m3 when the furrow length increased from 20 m to 40 m. The range of mean values of WUE due to the effect of furrow length from 20 to 40m was highly significant (P<0.01) only. The average of WUE was increased from 5.81 to 9.87 and 13.41 kg/m3 for CFI, AFI and SDI systems, respectively. The highest and lowest values of irrigation depth (ID), water application efficiency (WAE), water distribution efficiency (WDE) and applied water (AW) were 17.65-10.12cm, 75.25-52.46 %, 73.37 -36.45% and 61.20.

Automated Detection of Iris Furrows and their Influence on Dynamic Iris Volume Change

We introduced a new method for detecting iris surface furrows and identify its associations with dynamic changes in iris volume in healthy eyes. Swept-source optical coherence tomography was performed on 65 subjects with open angle under light and dark conditions. Iris boundaries were identified and a reconstruction of the anterior iris surface was obtained. Furrows were detected by identifying locally deep (minima) points on the iris surface and reported as furrow length in millimetres. Iris volume was quantified. Associations between furrow length and dynamic changes in iris volume were assessed using linear regression model. With pupil dilation, furrow length increased (15.84 mm) whereas iris volume decreased (−1.19 ± 0.66 mm3). Longer furrow length was associated with larger static iris volume, as well as smaller loss of iris volume with pupil dilation (β = −0.10, representing 0.1 mm3 less loss in iris volume per 10 mm increase in iris furrow length; P = 0.002, adjusted for age, gender and changes in pupil size). Our iris furrow length measurements are robust and intuitive. Eyes with longer furrows have larger iris volume and lose less volume during physiological pupil dilation. These findings highlight the potential for iris surface features as indicators of iris morphological behavior.

Improved volume balance using upstream flow depth for advance time estimation

Modification of classical volume balance models is one of the effective strategies to improving design of surface irrigation and optimal usage of water resources in agricultural section. In this paper, a modified volume balance model is developed to predict the advance curve in surface irrigation based on the variable actual depth at the upstream end of furrow. The simulations of the suggested structure are generated through a combination of different values of the furrow irrigation variables (inflow discharge, length of furrow, and infiltration parameters), to compare between different models and measured data. The results show that the modified volume balance is more accurate than previous equations by model efficiency of 0.94, 0.98, and 0.97 for furrow length of 60, 80, and 100m, respectively. Sensitivity analysis is made by changing only one input parameter including discharge, field slope, roughness coefficient and infiltration parameters at a time while keeping all others fixed. Furthermore, the inflow rate can have a considerable impact on the model estimations. Nevertheless, the developed model is more sensitive to decreasing inflow discharge amount than to increasing it.