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Microbial transport in soil caused by surface and subsurface drip irrigation with treated wastewater
Kouznetsov M.Y.,Pachepsky Y.A.,Gillerman L.,Gantzer C.J.
International Agrophysics , 2004,
Abstract: The objective of this work was to compare and simulate transport and fate of microorganisms from wastewater for surface and subsurface irrigation methods. Adsorption isotherms and water-content dependent survival were measured for fecal coliforms, somatic coliphages and F-specific RNA phages in batch experiments with treated wastewater and clay loam soil. Column experiments with surface and subsurface trickle irrigation were carried out for the same soil. Results of the column experiments were simulated with a combination of Richards equation for water transport and advective-dispersive model with the first-order nonlinear adsorption and moisture-dependent first-order die-off. Simulations showed that die-off rates in column experiments were much higher than in batch experiments for all three organisms. Somatic coliphages were the most persistent organisms probably because of lower adsorption and die-off. The subsurface irrigation appeared to be efficient in decreasing the number of pathogens in irrigated water and preventing their appearance on soil surface that could lead to produce contamination.
EFFECTS OF SALINE WATER ON TOMATO UNDER SUBSURFACE DRIP IRRIGATION: NUTRITIONAL AND FOLIAR ASPECTS
Kahlaoui,B; Hachicha,M; Rejeb,S; Rejeb,M.N; Hanchi,B; Misle,E;
Journal of soil science and plant nutrition , 2011, DOI: 10.4067/S0718-95162011000100007
Abstract: a field experiment on the effects of drip irrigation (di) and subsurface drip irrigation (sdi) with saline water (6.57 ds m-1) on three tomato cultivars (lycopersicon esculentum mill., cvs. rio tinto, rio grande and nemador) was carried out with the purpose to quantify physiological responses. the aim was to improve irrigation water management under saline conditions of tunisia. the trial was established in a silt-clayey soil with three regimes of irrigation: 100 %, 85 % and 70 % of crop water requirement. results evidenced a significant difference between the two irrigation systems for the three cultivars. growth parameters such as leaf area, chlorophyll content and mineral composition of leaves, petioles, stems and roots were affected significantly by the different treatments, particularly for rio tinto and nemador, being rio grande the more adapted. the fruit was the organ less affected. strong accumulation of na+ and cl- accompanied a reduction in ca2+, k+, mg 2+ and p content in the case of di. the distribution of these last necessary elements for plants nutrition under a strong accumulation of na+ and cl- depends on the cultivar and changes from one organ to another. sdi can be included as an effective option for tomato production in tunisia.
EFFECTS OF SALINE WATER ON TOMATO UNDER SUBSURFACE DRIP IRRIGATION: NUTRITIONAL AND FOLIAR ASPECTS  [cached]
B Kahlaoui,M Hachicha,S Rejeb,M.N Rejeb
Journal of Soil Science and Plant Nutrition , 2011,
Abstract: A field experiment on the effects of drip irrigation (DI) and subsurface drip irrigation (SDI) with saline water (6.57 dS m-1) on three tomato cultivars (Lycopersicon esculentum Mill., cvs. Rio Tinto, Rio Grande and Nemador) was carried out with the purpose to quantify physiological responses. The aim was to improve irrigation water management under saline conditions of Tunisia. The trial was established in a silt-clayey soil with three regimes of irrigation: 100 %, 85 % and 70 % of crop water requirement. Results evidenced a significant difference between the two irrigation systems for the three cultivars. Growth parameters such as leaf area, chlorophyll content and mineral composition of leaves, petioles, stems and roots were affected significantly by the different treatments, particularly for Rio Tinto and Nemador, being Rio Grande the more adapted. The fruit was the organ less affected. Strong accumulation of Na+ and Cl- accompanied a reduction in Ca2+, K+, Mg 2+ and P content in the case of DI. The distribution of these last necessary elements for plants nutrition under a strong accumulation of Na+ and Cl- depends on the cultivar and changes from one organ to another. SDI can be included as an effective option for tomato production in Tunisia.
Capability of HYDRUS-2D Simulation Model for Simulating Wetting Pattern in Soil under Subsurface Drip Irrigation Systems  [cached]
H. Naghavi,M. Hosseini nia,SH. karimi Googhari,M. Irandost
Journal of Science and Technology of Agriculture and Natural Resources , 2012,
Abstract: Knowing about the way water is distributed in the soil is essential for designing and managing the Subsurface Drip Irrigation systems (SDI). Since carrying out experiments to recognize the form of moisture distribution in the soil is too complicated and time-consuming, using numerical simulations can be an efficient, effective substitute method to design these systems. One of these models is HYDRUS-2D, which is able to simulate the movement of water, heat and solute in saturated and unsaturated conditions in soil. This research aims to figure out the extent to which the HYDRUS-2D model is able to estimate wetting pattern in soil around a dripper. The simulations’ findings were compared to the data gathered from the field, including SDI system in different irrigation times, and 72 hours after irrigation. Moreover, the rates of error were measured for all points and distances from the dripper in all times of irrigation and also beyond that. The results indicated that the model can simulate the changes, trend similar to what happened in the soil profile. However, it estimated the rate of soil moisture with higher errors in those points in which the wetting took place, with the maximum error rate being RMSE= 0.05 per every 1.5 hours after irrigation starting point in the depth of 30 centimeters where dripper is placed. Also, with an increase in the irrigation time, and soil moisture evening which resulted from redistribution of moisture, the model resulted in better estimations. 72 hours after finishing the irrigation, the estimates were closer to real figures with an average error estimate of RMSE= 0.002.
Effects of Using Subsurface Drip Irrigation and Treated Municipal Waste Water in Irrigation of Tomato  [PDF]
P. Najafi
Pakistan Journal of Biological Sciences , 2006,
Abstract: Whenever good quality water is scarce, water of marginal quality will have to be considered for using in agriculture. Municipal waste water is marginal quality water and using of this for irrigation can be an important consideration when its disposal is being planned in arid and semi-arid regions. In this study, secondary municipal effluent was used for irrigation of tomato. This effluent is using activated sludge process to treat the municipal wastewater. Five different irrigation treatments were designed with three replications. The treatments were as follows: T1: Furrow irrigation with drinking water network. T2: Surface drip irrigation (DI) with treated wastewater. T3: Sub surface drip irrigation (SDI) in 15 cm depth with treated wastewater. T4: Sub surface drip irrigation (SDI) in 30 cm depth with treated wastewater. T5: Furrow irrigation with treated wastewater. Crop water requirement was determined by ET-HS model. Also, in this study, chemical and microbiological characteristics of soil, water and crops have been analyzed. The results of this study indicated that application of DI and SDI could be control environmental contamination and in comparison surface irrigation, decreases the pollution problems in the soil. Also, the highest yield was obtained from T2 and T3, which was about 52 tons ha-1 (18 tons ha-1 higher than the average yield of the T1). A part of this increased yield can be related to better soil moisture and increased available nitrogen in the root zone. Additionally, with regard to health problem, minimum contact was generated between the effluent and the workers or the aerial plant parts. But the microbiological tests indicated that among of effluent treatments, T3 had better microbiological quality of tomato.
Irriga o localizada subsuperfical: gotejador convencional e novo protótipo Subsurface drip irrigation: conventional dripper and new prototype  [cached]
Wanderley de J. Souza,Tarlei A. Botrel,Rubens D. Coelho,Nilson A. V. Nova
Revista Brasileira de Engenharia Agrícola e Ambiental , 2012, DOI: 10.1590/s1415-43662012000800001
Abstract: A irriga o por gotejamento subsuperficial, que utiliza um sistema protetor do emissor para evitar entupimento do mesmo por raiz e partículas sólida do solo, pode ser viável em rela o a um sistema convencional. Prop s-se, com este trabalho, avaliar o desempenho de um sistema para prote o de emissor e comparar os resultados com um sistema que utiliza emissor convencional para irriga o por gotejamento subsuperficial. O sistema com protetor foi construído com materiais de baixo custo: mangueira de polietileno, microtubo, conector e um gotejador para controlar a vaz o e no sistema convencional utilizou-se um emissor comercial. Após 12 meses de avalia o o sistema com protetor demonstrou bom desempenho com vaz o relativa média de 0,97 e 0,98 em vasos com e sem cultura, respectivamente, n o apresentando problemas de entupimento e tendo menor custo. No sistema convencional constatou-se vaz o relativa de 0,51 e 0,98 em vasos com e sem cultura, respectivamente, grau de entupimento por raiz de 49,22% e emissores com solo em seu interior. Desta forma, o uso do emissor com sistema de prote o indicou viabilidade para irriga o subsuperficial por gotejamento, nas condi es desta pesquisa. Subsurface drip irrigation that uses an emitter protection system to avoid its clogging by roots and soil particles may be viable compared to a conventional system. The objective of this work was to evaluate the performance of a system with emitter protection, and to compare the results with a system that uses a conventional emitter for subsurface drip irrigation. In the system with protection an inexpensive materials polyethylene hose, microtube, connector, and a dripper to control the flow rate were used; and, in the conventional system a commercial emitter was used. After 12 months of evaluation, the system with protector showed good performance, with relative average flow rate of 0.97 and 0.98 in pots with and without crop, respectively, showing no clogging problems and lower cost. In conventional system relative flow rate of 0.51 and 0.98 were observed in pots with and without crop, respectively, also clogging degree by roots of 49.22%, and emitters with soil inside was observed. Thus, the use of emitter with protection presented feasibility for subsurface drip irrigation, under conditions used in this research.
Aspectos produtivos e de qualidade do mel o sob gotejo subterraneo e “mulching” plástico = Quantitative and qualitative characteristics of melon under subsurface drip irrigation and mulch
Rodrigo Otávio Camara Monteiro,Rubens Duarte Coelho,Paulo César Tavares de Melo,Priscylla Ferraz
Acta Scientiarum : Agronomy , 2007,
Abstract: O gotejo subterraneo e o “mulching” plástico s o técnicas atuais na irriga o de mel o que tentam reduzir ao máximo os desperdícios em virtude da demanda crescente por recursos de água. No entanto, carecem de estudos devido à dificuldade de se conhecer os seus reais efeitos sobre o rendimento e a qualidade do mel o. O objetivo deste trabalho foi estudar aspectos produtivos e de qualidade do meloeiro num Nitossolo Vermelho eutrófico, submetido aos efeitos do “mulching” plástico, em condi es de gotejamento superficial e subsuperficial. Verificou-se que o efeito do filme plástico nas respostas agron micas do meloeiro foi mais pronunciado do que a profundidade de gotejamento. O uso da cobertura plástica incrementou o peso médio de frutos, a produtividade, o diametro longitudinal e transversal, espessura de polpa, oBrix, além de proporcionar precocidade de crescimento. The subsurface drip irrigation and mulch are modern techniques in melon irrigation that try to reduce water consume. However, thereare few studies about it, since it is difficult to evaluate melon's quantitative and qualitative characteristics. The aim of this work is to study such characteristics on melons under subsurface drip irrigation and mulch in clayey soil. The effects of mulch on agronomicparameters were more evident than those of subsurface drip irrigation. Mulch increased fruit weight, productivity, longitudinal and transversal diameter, pulp thickness and soluble solid content, besides providing crop's precocious growth.
Simulation of soil water dynamics in triploid Populus tomentosa root zone under subsurface drip irrigation.
地下滴灌条件下三倍体毛白杨根区土壤水分动态模拟

席本野,贾黎明,王 烨,李广德
应用生态学报 , 2011,
Abstract: Based on the observed data of triploid Populus tomentosa root distribution, a one-dimensional root water uptake model was proposed. Taking the root water uptake into account, the soil water dynamics in triploid P. tomentosa root zone under subsurface drip irrigation was simulated by using HYDRUS model, and the results were validated with field experiment. Besides, the HYDRUS model was used to study the effects of various irrigation technique parameters on soil wetting patterns. The RMAE for the simulated soil water content by the end of irrigation and approximately 24 h later was 7.8% and 6.0%, and the RMSE was 0.036 and 0.026 cm3·cm-3, respectively, illustrating that the HYDRUS model performed well in simulating the short-term soil water dynamics in triploid P. tomentosa root zone under drip irrigation, and the root water uptake model was reasonable. Comparing with 2 and 4 L·h-1 of drip discharge and continuous irrigation, both the 1 L·h-1 of drip discharge and the pulsed irrigation with water applied intermittently in 30 min periods could increase the volume of wetted soil and reduce deep percolation. It was concluded that the combination of 1 L·h-1 of drip discharge and pulsed irrigation should be the first choice when applying drip irrigation to triploid P. tomentosa root zone at the experiment site.
Net melon performance as affected by the drip irrigation depth and mulching
Monteiro, Rodrigo OC;Coelho, Rubens D;Melo, Paulo CT de;Ferraz, Priscylla;Chaves, Sérgio WP;Shirahige, Fernando H;Beltrame Neto, Eugênio;Piedade, S?nia Maria de S;
Horticultura Brasileira , 2008, DOI: 10.1590/S0102-05362008000400005
Abstract: the modern techniques of water supply through irrigation can substantially reduce water waste, which contributes to attend the enlarging water demand. the objective of this work was to study the influence of subsurface drip irrigation and mulching over melon yield and quality characteristics, in a sandy soil (typic hapludox). the experimental design was blocks at random, with four replications. treatments were displayed in a 2 x 3 factorial (with and without mulching x surface and 0.20 and 0.40 depth subsurface drip irrigation). mulching using double-sided silver/black film increased fruit average mass, plant production, yield, daily growth rate for plant height and crown diameter, fruit distal diameter, and pulp thickness. the subsurface drip irrigation at 0.20 m depth resulted in larger fruit average mass, plant production, and yield than surface and 0.40 m depth drip irrigation.
Effect of Drip Irrigation, N-Fertigation and Cultivation Methods on the Yield and Quality of Carrot
Jacek Dy ko, Stanis aw Kaniszewski
Vegetable Crops Research Bulletin , 2007, DOI: 10.2478/v10032-007-0027-3
Abstract: In the years of 2004-2006 research on influence of surface and subsurface drip irrigation on yield and quality of carrot grown on ridges and on the flat ground was investigated. Irrigation was started at soil water potential of 30-40 kPa. Nitrogen fertilizers (100 kg.ha-1) were applied in two rates. The first rate was preplant applied, the second was used by fertigation. In the control treatment without irrigation, the second rate of nitrogen was applied by broadcasting. Surface and subsurface drip irrigation significantly increased the yield of carrot. In cultivation on ridges higher yield of the carrot was obtained when surface drip irrigation was applied as compare to subsurface method. Carrot cultivated on ridges produced significantly longer roots than cultivated on flat ground. Generally the surface and subsurface drip irrigation decreased dry matter content and total N content in carrot roots. Drip irrigation at both cultivation methods increased pH and decreased the salt concentration of the soil.
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