scholarly journals Effect of Bypass-Flow on Leaching of Salts in a Cracking Soil in the Nile Delta

Water ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 993
Author(s):  
Haruyuki Fujimaki ◽  
Hassan Mohamed Fahmy Abd El Baki
Keyword(s):  
Pore Water ◽  
Root Zone ◽  
Nile Delta ◽  
Shallow Groundwater ◽  
Soil Surface ◽  
Irrigated Agriculture ◽  
Bypass Flow ◽  
Before And After ◽  
Flow Through ◽  
The Difference

Salinity is a major threat to the sustainability of irrigated agriculture in arid and semi-arid regions. Leaching is the primary measure for removing excess salts from the root zone, but not all water applied to the soil surface contributes to the removal of salts. In clayey soils, bypass flow along cracks can occur without being mixed with saline pore water in the matrix. To present a field dataset to quantitatively evaluate the contribution of bypass flow to the leaching of salts, soil sampling and monitoring of groundwater and discharge from a tile drain were carried out in farmland having a cracking soil in the Nile Delta. The electrical conductivities of 1:2 extracts were measured to evaluate the salinity of the soil. The first evidence for the occurrence of significant bypass flow through cracks was the salinity of the pore water, which was nearly triple that of the shallow groundwater and outflow from drainage. Second, the difference in root zone salinity before and after paddy rice cultivation was not significant. Third, the gradient of the groundwater table was very small. in spite of the low saturated hydraulic conductivity. Fourth, the salinity of the outflow from the tile drain dropped just after irrigation or rain. These results indicated that bypass flow through cracks played a significant role in the drainage process in the soil, and that nearly half of the water bypasses through cracks in the field with a cracking soil.

scholarly journals Salinisasi Lahan dan Permasalahannya di Indonesia

2020 ◽  
Vol 14 (2) ◽  
pp. 91
Author(s):  
Vicca Karolinoerita ◽  
Wahida Annisa
Keyword(s):  
Agricultural Land ◽  
Sea Water ◽  
Root Zone ◽  
Salt Content ◽  
Shallow Groundwater ◽  
Soil Salinization ◽  
Paddy Fields ◽  
Irrigated Agriculture ◽  
Groundwater Levels ◽  
Chemical Conditions

<p><strong>Abstrak. </strong>Salinisasi tanah merupakan proses peningkatan kadar garam mudah larut di dalam tanah sehingga terbentuk lahan salin. Salinitas adalah salah satu cekaman abiotik yang mengakibatkan berkurangnya hasil dan produktivitas tanaman pertanian. Setiap tahun luas lahan sawah yang ditinggalkan petani akibat mengalami salinisasi terus meningkat. Di Indonesia salinitas umumnya terjadi di lahan pertanian dekat pantai, disebabkan karena kenaikan permukaan laut akibat perubahan iklim. Diperkirakan lahan dekat pantai yang rentan mengalami salinitas seluas 12,020 juta ha atau 6,20% dari total daratan Indonesia. Problem salinitas pada pertanian beririgasi sering terkait dengan muka air tanah. Peningkatan kapilaritas dari muka air tanah dangkal akan membawa kembali garam-garam masuk ke daerah perakaran dan menjadi suatu sumber garam berkelanjutan. sedangkan salinitas di lahan rawa pasang surut dipengaruhi oleh pergerakan pasang surut air laut dengan tingkat salinitas yang bervariasi. Tanaman mempunyai kisaran toleransi tertentu terhadap perubahan bahkan cekaman lingkungan untuk selanjutnya dapat beradaptasi, termasuk pada cekaman salinitas. Kondisi biofisik dan kimia lahan sawah terdampak yang tidak menguntungkan tanaman tersebut memerlukan upaya pengelolaan lahan dan sistem budidaya tanaman secara tepat agar dicapai tingkat produksi yang optimal.</p><p> </p><p><em><strong>Abstract</strong>. Soil salinization is the process of increasing the soluble salt content in the soil to form a saline soil. Salinity is an abiotic stress that results in reducing yield and productivity of agricultural crops. The area of paddy fields left by farmers as a result of experiencing salinization continues to increase every tear. In Indonesia, salinity generally occurs in agricultural land near the coast, caused by sea level rise due to climate change.  It is estimated that land near the coast that is prone to experiencing salinity is 12.020 million ha or 6.20% of the total land area of Indonesia. The problem of salinity in irrigated agriculture is often related to the water table. The increase in capillarity from shallow groundwater levels will bring back salts into the root zone and become a continuous salt source.  Salinity in tidal swamps is influenced by the tidal movement of sea water with varying salinity levels. Plants have a certain tolerance range to the changes and even environmental stress so that they can then adapt, including to salinity stress. The biophysical and chemical conditions of the affected paddy fields that are not beneficial to the plant, requires proper land management and crop cultivation systems in order to achieve optimal production levels.</em></p>

The effect of winter flood irrigation with saline water on groundwater in a typical irrigation area

2014 ◽  
Vol 15 (2) ◽  
pp. 356-361
Author(s):  
Yujiang He ◽  
Wenjing Lin ◽  
Guiling Wang
Keyword(s):  
Root Zone ◽  
Saline Water ◽  
Shallow Groundwater ◽  
Northwest China ◽  
Soil Electrical Conductivity ◽  
Hydraulic Characteristics ◽  
Soil Environment ◽  
Flood Irrigation ◽  
Before And After ◽  
Winter Flood

Flood irrigation in the winter has been widely applied in northwest China for several years, but little attention has been paid to the flood irrigation program to date. In order to seek a reasonable irrigation quota, a flood irrigation experiment using two common quotas (1,800 and 1,200 m3 ha−1) was conducted in an area irrigated by saline water in the Nanjiang basin with shallow groundwater. Soil electrical conductivity in six treatments irrigated by saline water, with various salinity backgrounds, was investigated using Hydra and DDS-307 before and after flood irrigation. The results indicate that the quota of 12,00 m3 ha−1 was small enough to prevent soil salt from leaching out of the root zone. Although the quota of 1,800 m3 ha−1 may guarantee regular plant growth in the following year, it resulted in at least 267.2 g m−2 of salt entering the shallow groundwater. Therefore, flood irrigation had an important and profound effect on plants, soil environment, and shallow groundwater. The quota of flood irrigation in winter should be determined cautiously according to the hydraulic characteristics and salt background of the soil.

The nutrient retention by ecotone wetlands and their modification for Baiyangdian lake restoration

1995 ◽  
Vol 32 (3) ◽  
pp. 159-167 ◽  
Author(s):  
Yin Chengqing ◽  
Lan Zhiwen
Keyword(s):  
High Efficiency ◽  
Root Zone ◽  
Nutrient Retention ◽  
Soil Surface ◽  
Terrestrial Ecosystems ◽  
Surface Flow ◽  
Environmental Risks ◽  
Baiyangdian Lake ◽  
Flow Through ◽  
Potential Use

Shallow and eutrophic Baiyangdian Lake is a decaying lake and has broad ecotone wetlands, composed of reed communities and ditches. Experiments were carried out to study the fate of nutrients and organic pollutants during the runoff, flowing from a contaminated river through the ecotone to the lake. Under moderate hydrological conditions, water flows through the ditches and through the root zone soil of the reed community. The retention of total nitrogen (TN) and total phosphorus (TP) by surface flow through a 300-m ditch was measured to be 42% and 65% respective-ly. The retention of TN and TP by an 8-m stretch of reed community soil was 59% and 88%. The retention by the reed community mainly happened at the rhizosphere below the soil surface. The removal of organic matter was also observed. The retention of nutrients by the subsurface flow was more than 10 times greater than that by surface flow. The harvest of reed biomass recycles 1120 metric tons of nitrogen and 53 tons of phosphorus from lake-side ecotones back to the terrestrial ecosystems each year. There is a potential use of ecotone wetlands as the advanced treatment facility for nutrient-rich water, and a good design can enhance the treatment efficiency. Ecotone engineering for advanced water treatment is an economical method with low environmental risks and high efficiency.

Tem analysis of multiple-energy arsenic implanted and Rta'd silicon

1987 ◽  
Vol 45 ◽  
pp. 246-247
Author(s):  
R.A. Herring
Keyword(s):  
Device Fabrication ◽  
High Concentration ◽  
Tem Analysis ◽  
Defect Clusters ◽  
High Fluences ◽  
Small Defect ◽  
Before And After ◽  
The Matrix ◽  
The Difference ◽  
Factor Type

Rapid thermal annealing (RTA) of ion-implanted Si is important for device fabrication. The defect structures of 2.5, 4.0, and 6.0 MeV As-implanted silicon irradiated to fluences of 2E14, 4E14, and 6E14, respectively, have been analyzed by electron diffraction both before and after RTA at 1100°C for 10 seconds. At such high fluences and energies the implanted As ions change the Si from crystalline to amorphous. Three distinct amorphous regions emerge due to the three implantation energies used (Fig. 1). The amorphous regions are separated from each other by crystalline Si (marked L1, L2, and L3 in Fig. 1) which contains a high concentration of small defect clusters. The small defect clusters were similar to what had been determined earlier as being amorphous zones since their contrast was principally of the structure-factor type that arises due to the difference in extinction distance between the matrix and damage regions.

Changes in Platelet Aggregability after Ovariectomy

1979 ◽  
Vol 42 (04) ◽  
pp. 1332-1339 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Takeshi Motomiya ◽  
Minoru Sonoda ◽  
Noboru Miyagawa
Keyword(s):  
Platelet Count ◽  
Platelet Activation ◽  
Ovarian Hormones ◽  
Control Group ◽  
Platelet Aggregability ◽  
Appearance Rate ◽  
Before And After ◽  
The Difference ◽  
Induced Aggregation ◽  
Observation Period

SummaryChanges in platelets in 48 patients with uterine myoma before and after hysterectomy with and without ovariectomy were examined. Bilateral ovariectomy in 25 cases (ovariec-tomized group) and unilateral or non-ovariectomy in 23 cases (control group) were performed at the hysterectomy. Platelet count and an appearance rate of secondary aggregation decreased at one day after and increased at one week after the operation, similarly in both the ovariectomized and the control group. The appearance rate of secondary aggregation was reflected in an intensity of aggregation at 5 min after the addition of reagent to PRP. At one month after the operation, the appearance rate of secondary aggregation induced by 3 μM ADP showed a statistically significant decrease in comparison with the preoperation value (P <0.05) and the enhancement of 5-min aggregation was still observed in the control group, while ceased in the ovariectomized group. The difference between the two groups was significant (P < 0.05). There was almost no change in the speed and intensity of primary and secondary aggregation during the observation period. No significant differences in collagen-induced aggregation were noted between the two groups. The results suggest that ovarian hormones, mainly estrogen, facilitate platelet activation which is mediated by the so-called secondary aggregation.

PENGARUH TERAPI TERTAWA TERHADAP PENURUNAN TEKANAN DARAH LANSIA DI UPT PANTI WREDHA BUDHI DHARMA YOGYAKARTA

2019 ◽  
Vol 13 (1) ◽  
Author(s):  
Niken Setyaningrum ◽  
Andri Setyorini ◽  
Fachruddin Tri Fitrianta
Keyword(s):  
Blood Pressure ◽  
Data Analysis ◽  
The Elderly ◽  
Control Group ◽  
Group Comparison ◽  
Control Blood Pressure ◽  
Men And Women ◽  
Treatment Of Hypertension ◽  
Before And After ◽  
The Difference

ABSTRACTBackground: Hypertension is one of the most common diseases, because this disease is suffered byboth men and women, as well as adults and young people. Treatment of hypertension does not onlyrely on medications from the doctor or regulate diet alone, but it is also important to make our bodyalways relaxed. Laughter can help to control blood pressure by reducing endocrine stress andcreating a relaxed condition to deal with relaxation.Objective: The general objective of the study was to determine the effect of laughter therapy ondecreasing elderly blood pressure in UPT Panti Wredha Budhi Dharma Yogyakarta.Methods: The design used in this study is a pre-experimental design study with one group pre-posttestresearch design where there is no control group (comparison). The population in this study wereelderly aged over> 60 years at 55 UPT Panti Wredha Budhi Dharma Yogyakarta. The method oftaking in this study uses total sampling. The sample in this study were 55 elderly. Data analysis wasused to determine the difference in blood pressure before and after laughing therapy with a ratio datascale that was using Pairs T-TestResult: There is an effect of laughing therapy on blood pressure in the elderly at UPT Panti WredhaBudhi Dharma Yogyakarta marked with a significant value of 0.000 (P <0.05)

Klein with Lacan: A Study on the Reception of Lacanian Ideas in Uruguay and Its Effects on Clinical Practices (1955–82)

2020 ◽  
Vol 22 (3) ◽  
pp. 341-361
Author(s):  
Gonzalo Grau-Pérez ◽  
J. Guillermo Milán
Keyword(s):  
Clinical Practice ◽  
Clinical Material ◽  
Clinical Practices ◽  
Before And After ◽  
The Difference ◽  
The 1960S ◽  
The Relationship ◽  
Discursive Approach ◽  
The Way ◽  
Clinical Cases

In Uruguay, Lacanian ideas arrived in the 1960s, into a context of Kleinian hegemony. Adopting a discursive approach, this study researched the initial reception of these ideas and its effects on clinical practices. We gathered a corpus of discursive data from clinical cases and theoretical-doctrinal articles (from the 1960s, 1970s and 1980s). In order to examine the effects of Lacanian ideas, we analysed the difference in the way of interpreting the clinical material before and after Lacan's reception. The results of this research illuminate some epistemological problems of psychoanalysis, especially the relationship between theory and clinical practice.

FRACTIONAL DETERMINATIONS OF URINARY 17-KETOSTEROIDS IN HYPEREMESIS GRAVIDARUM

1962 ◽  
Vol 41 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Pentti A. Järvinen ◽  
Sykkö Pesonen ◽  
Pirkko Väänänen
Keyword(s):  
Hyperemesis Gravidarum ◽  
First Trimester ◽  
Control Group ◽  
Before And After ◽  
Daily Urine ◽  
First Trimester Of Pregnancy ◽  
The Difference

ABSTRACT The fractional determination of 17-ketosteroids in the daily urine was performed in nine cases of hyperemesis gravidarum and in four control cases, in the first trimester of pregnancy both before and after corticotrophin administration. The excretion of total 17-KS is similar in the two groups. Only in the hyperemesis group does the excretion of total 17-KS increase significantly after corticotrophin administration. The fractional determination reveals no difference between the two groups of patients with regard to the values of the fractions U (unidentified 17-KS), A (androsterone) and Rest (11-oxygenated 17-KS). The excretion of dehydroepiandrosterone is significantly higher in the hyperemesis group than in the control group. The excretion of androstanolone seems to be lower in the hyperemesis group than in the control group, but the difference is not statistically significant. The differences in the correlation between dehydroepiandrosterone and androstanolone in the two groups is significant. The high excretion of dehydroepiandrosterone and low excretion of androstanolone in cases of hyperemesis gravidarum is a sign of adrenal dysfunction.

Automatic Tread Gaging Machine

1979 ◽  
Vol 7 (1) ◽  
pp. 31-39
Author(s):  
G. S. Ludwig ◽  
F. C. Brenner
Keyword(s):  
Experimental Tests ◽  
Automatic Machine ◽  
Wear Rates ◽  
Handling Device ◽  
Straight Line ◽  
Component Systems ◽  
Before And After ◽  
Good Repeatability ◽  
The Difference ◽  
Straight Lines

Abstract An automatic tread gaging machine has been developed. It consists of three component systems: (1) a laser gaging head, (2) a tire handling device, and (3) a computer that controls the movement of the tire handling machine, processes the data, and computes the least-squares straight line from which a wear rate may be estimated. Experimental tests show that the machine has good repeatability. In comparisons with measurements obtained by a hand gage, the automatic machine gives smaller average groove depths. The difference before and after a period of wear for both methods of measurement are the same. Wear rates estimated from the slopes of straight lines fitted to both sets of data are not significantly different.

The application of the root zone method for the treatment and reuse of high-strength abattoir waste in Mexico

1997 ◽  
Vol 35 (5) ◽  
pp. 271-278 ◽  
Author(s):  
Fermin Rivera ◽  
Alan Warren ◽  
Colin R. Curds ◽  
Esperanza Robles ◽  
Alejandro Gutierrez ◽  
...  
Keyword(s):  
Treatment Process ◽  
Root Zone ◽  
Ornamental Plants ◽  
High Strength ◽  
Faecal Coliforms ◽  
Treatment Efficiency ◽  
Zone Method ◽  
Stage System ◽  
Flow Through ◽  
Two Stages

A two-stage system for treating high-strength wastewater from an abattoir at Pachuca, Mexico is described. The system consists of an anaerobic digester followed by an artificially-constructed wetland which employs horizontal subsurface flow through the root zone of emergent hydrophytes planted in a gravel substrate. The main goals of this study were to monitor the treatment efficiency of the system for the first twelve months of operation and to assess the suitability of the effluent for irrigation purposes. The treatment efficiency during the twelve month period was generally good with mean removal efficiencies of 88.5% for BOD5, 87.4% COD, 89% suspended solids, 73.6% organic nitrogen and &gt;99% faecal coliforms. Removal rates were generally poor for orthophosphates, NH3-nitrogen and NO3-nitrogen. The differing roles of the two stages in the treatment process are discussed. Although not suitable for irrigating crops, the effluent is being successfully used for the irrigation of ornamental plants and recreational lands.

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