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The agricultural development program is associated with a significant investment in irrigation technologies; sometimes the technical parameters of the operation of parts and accessories are unknown, which is why they need to be evaluated, which is why this work aims to design under criteria hydraulic and based on ISO standards, test benches for the evaluation of irrigation components, in particular, sprinkler and localized. The design proposal used ISO 9001:2015 standards, which provide guidelines for quality control and calibration of measurement equipment, ISO/IEC 17025, which provides guidelines for the technical competence of laboratories and establishes requirements. for planning and designing experiments. These standards were taken into account for the organization and distribution of the test benches within the laboratory for adequate use of the area. Accessories that include: drippers, diffusers and low-flow mini-sprinklers, micro-sprinklers, low-, mediumand high-flow sprinklers, nozzles for irrigation machines, pressure losses in connections, hydraulic valves and filters, among others, may be evaluated. As part of the laboratory, five pumping equipment is needed with flow rates between 0.5 and 25 L/s and pressures in the range of 400 and 600 kPa. The designed hydraulic laboratory will require investments in equipment valued at 95,523.20 USD, equivalent to 2,292,556.80 CUP according to the current exchange rate. [ABSTRACT FROM AUTHOR]

The precise determination of the coefficients of the Class A evaporimeter tank allows us to estimate the reference evapotranspiration (ETo) and obtain real values of water needs of the crops. In the present work, the Kp coefficient was estimated using the two equations proposed by FAO, Snyder, Orang, Cuenca and the ETo Ratio determined by the Penman-Monteith (PM) method and the Eo determined in the class A evaporimeter. For the estimation of Kp, the climatic data from the climatic station of the Agricultural Engineering Research Institute in Alquizar for the period 1975-1990; with these coefficients, the ETo was calculated from evaporation data for the period 2019-2022, which was contrasted with the ETo estimated by the Penman-Monteith equation; the statistical parameters were determined for the cross analysis between the different methods to estimate ETo: mean absolute error, coefficient of agreement, efficiency and the coefficient of determination. The statistical parameters applied in the validation of the models indicated greater precision in the estimation of ETo for the decadal values with the FAO 1 equations and the ETo/Eo relationship, while for the monthly values these two models and the Cuenca model. It is recommended, due to its ease of obtaining, the use of the Kp obtained by the ETo/Eo model for the determination of the ETo in the region studied. [ABSTRACT FROM AUTHOR]

A potential increase in the areas planted with avocado in Cuba will demand an increase in the areas under irrigation for this crop, which will require the most precise knowledge of their irrigation demands. In response to the above, the present work was carry out in a young plantation of avocado cv Govin planted with a 6 x 6 m frame in Red Ferralitic soil in the municipality of Alquizar, Artemisa Province, Cuba and irrigated through porous pipes. Water consumption was calculated using the simplified water balance equation and soil moisture variation was monitored with tensiometers placed at depths from 15 to 90 cm whose readings were converted to soil moisture using the calibration equations determined in situ. The ETo was determined using the Penman-Monteith equation. The total ETc in the period February/2020-May/2021, was 965.4 mm when the plants reached an average height of 126 cm vs. 20 cm at the planting date. Average daily values of decennial consumption were 2.72, 2.26 and 2.01 for the periods of February-April 2020, May to October 2020 and January-April 2021, with Kc values of 0.47 and 0.48 for the rainy and dry seasons, respectively. These coefficients can be used in determining the demand for water for avocado plantations in development. Given the scarcity of information on the irrigation demand and its effect on the production of this crop, it is necessary to continue research that includes plantations in production and other cultivars. [ABSTRACT FROM AUTHOR]

The work was developed at the Agricultural Engineering Research Institute (¨Pulido¨), located in Alquízar, Artemisa province, Cuba. The general objective of the research was to determine the flood resistance time in the cultivation of soybean variety CEB-2 in cold season and spring, determining the drainage time for the projection of these systems. The crop was sown in pots with a compacted Red Ferralitic soil, the experimental design applied was that of Random Blocks, the treatments consisted of flooding the pots for 24, 48, 96 and 144 hours in the early flowering phase, with a witness without flooding. The analysis of the yield and its components, specifically the average weight of the seeds, facilitated the selection of the permissible flooding time for the crop. The results showed that in the first 24 hours of flooding, no effect of excess humidity was observed on grain production, so this is considered the drainage time of the crop, from this threshold value there is a reduction between 0,14 and 0,20% of the relative production of fresh grains for each hour of flooding and a loss of approximately 50% is reached between 67 and 84 hours of excess humidity. The plants presented losses in the weight of the pods, weight of seeds per plant, weight of 100 grains when they were subjected to flooding from 24 hours to 144 hours. [ABSTRACT FROM AUTHOR]

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Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Irrigation porous pipe are localized irrigation system that applied water in a continuous way using a porous pipe that exude water along its long and in the totality or part of its surface, in contact with the soils surface, soil capillarity act over the pipe and when the soil is sufficient wet, the pipe can regulate its water flow. There are different types of porous pipes in the market, but the best results have been obtained with exuding pipe made of geotextil fabric. This irrigation system are introduced in Europe at commercial scale and also en some Latin American countries, while in Cuba the Agricultural Engineering Research Institute in collaboration with the Research Tobacco Institute and the Spanish enterprise VisaReg are carrying out research in the use of this irrigation system in various crops. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this work is to determine the total soil water availability and easily usable reserve for plants as a function of predominant soil texture. That will be done from information existing for the most important Cuban soils. It will be used as a tool that facilitates efficient irrigation programming. Data were available from 131 soil subtypes and 11 soil groupings, according to the database of the Agricultural Engineering Research Institute (IAgric) of Cuba. The soil depth considered was 0.5 m and a predominant particle size value was assigned to each soil profile according to its texture. Values were adjusted with a logarithmic regression analysis of the gravimetric and volumetric soil water content corresponding to the point of field capacity (Cc) and permanent wilting point (PMP). The values of the Total Available Water in the Soil (ADP) and the Easily Usable Reserve (RFU) were also quantified. The obtained relationships allow predicting in more than 90%, the variation of the limits of these soil water reserves, based on the predominant particle size in its textural composition. The ranges of variation of these limits are higher than the ranges defined at international level for silt and clay, which is associated with the characteristics of the predominant clay in many Cuban soils. The results have a high practical value as a basis for the efficient programming of crop irrigation and allow reducing the hard field and laboratory work involved in these studies. [ABSTRACT FROM AUTHOR]

Grain sorghum is a crop with increased popularity between farmers in Cuba, where it is mainly used for animal feed; much of the areas planted with sorghum are irrigated, and in these sense, it is important to know the water requirement and crops coefficient for an adequate year plan of the sorghum's water demand. In order to respond to this demand, it were revise the data of some experiments conducted during the years 1986-1987 in the Agricultural Engineering Institute Research Station, in these experiments, were selected the treatments were irrigation was always applied when soil moisture descends at 85 % of field capacity (50 % of total available water). During the dry season (short days and low temperature), crop cycle was 120 days, and total season water consumption was 490 mm, while in the wet season (longest day and high temperatures), crop cycle was 90 days and total crop's water consumption was 412 mm; crops coefficients (Kc) during initial, development middle and maturity crop's development periods were 0.6, 1.3, 1.1 y 0.6 for dry season and 0.4, 0.9, 0.8 y 0.8 for wet season respectively. The comparison of Kc and total water consumption found in these work with those in the international literature didn't showed great differences; and it was considered a 4.5 mm value of crop peak daily water demand and the Kc adequate to calculate grain sorghum irrigation water demand in Cuba. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The work was carried out in the Scientific Unit of Base (UCTB "Pulido"), located in the Alquízar municipality of Artemisa province with the general purpose of studying the effect of the excess of soil damping on corn, variety Tuzón, in the bloom phase, and to determine the time of drainage for the projection of drainage systems in winter time. The corn was sowed in 20 pots with Ferralitic Red compacted soil. The experimental design was that of blocks at random, the treatments consisted on flooding the pots during 24, 48, 96 and 144 hours with a witness not flooded. The results showed that in the bloom phase from the beginning of the flood occurred a reduction in the relative production of grains of 0.23 % per hour of flooding and a loss of 50 % was reached approximately with 72 hours of excess of humidity. The flooding of the crop didn't affect in a significant way the number of leaves for plant neither it caused differences in the diameter of the shafts. The plants presented losses in the weight of the ears, weight of the grains, decrease of the longitude of the ear and diameter of the same ones when they were subjected to the flooding of 144 hours. In this case the corn shows a minimum threshold (0.0) for what the reduction in the yield and its components registered immediately when beginning the flooding. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil tillage induced soil´s compactation, reduce soil porosity, increase bulk density and as consequences, reduced soil´s infiltration capacity. In order to study the effect of two soil´s tillage methods in soil´s infiltration capacity, was carry out this work in a ferralitic red soil on the Agricultural Engineering Research Institute Experimental Station where there is under trials two tillage system; soil tillage using arrow plow and tiller (PM) and conventional tillage with mouldboard and disc ploughs (PC); in both plot were determined the soil infiltration using infiltrometers rings (three repetitions in each plot), soil water content was determined before the infiltration test and immediately and 24 hours after the test, were it was determined also soil bulk density, infiltration equations for each ring were determined using Kostiakov´s equation.Until 30 cm soil depth, soil bulk density (Bd) in treatment PM was lower than in PC, but at 40 cm soil Bd values were similar, in both cases the Bd values obtained were higher than typical values reported for this soils; Kostiakov´s equation parameters K and n from accumulated soil infiltration in PM (K =8,54, n= 0,788) and PC (K =7.49, n= 0,644) were significatively different (pË‚ 0.05), basic infiltration values were 0.56 and 0.43 mm min-1 for PM and PC respectively. The results showing the posibilities for increase water use efficiencies through the increase in soil infiltration changing the traditional soil´s working system to less soil´s intervention system. [ABSTRACT FROM AUTHOR]

In present work the net norms of the crops tomato, garlic, lettuce and corn are adjusted in function the incidence of the variability and the climatic change in Cuba, in that case it intended as objective to estimate the irrigations requirements to future of these crops of agricultural interest in the western area of Cuba, through the use of tools computations of modelation of the agricultural systems and of climatic regional model, that situation facilitate the precision of the norms toward later periods (2030 and 2050), to create the alternatives that are required and to achieve a correct efficient use of the disponibility water resource by virtue of the readiness that one has.The results indicated that one waits an increase in the reference evapotranspiration and the reduction in the precipitations what will cause an increase of the net norms of 5% in the tomato HC 3880, 14% in the Vietnamesegarlic, 19% in lettuce BSS and 8% in corn T66, what will indicate in the successive thing the application of a handling adaptation in the watering presage. [ABSTRACT FROM AUTHOR]

The main objective of this work is to do a diagnostic focused in water resource of vulnerabilities of agricultural systems in the Perico municipality of Matanzas province, for sustainability of their productions and adaptation capacity for actual and future climate change and variability. The study was realized in “La Angelina" that bellows to cooperative CCSF, ¨José Martí¨, in the north of Perico municipality. It was due a recompilation and analysis of previous available national and local information. For precision of diagnostic it were realized field visits, interviews to producers and directive personal and it were taken soil samples and direct determinations of soil properties in representative points. The results showed that the area “La Angelina" for its specific characteristics of soil and hydrology is a particular case that should have an special attention, because if it is not well oriented water and soil resources management it may conduce to an small but important ecological disaster, and this situation might be worse in a variability and climate change horizon. The main recommendations involves measures that can increase the efficiency in water use for agricultural production, which include a better organization and irrigation and drainage systems management and to promote changes in land preparation technologies and to implement in demonstrative areas the principles of conservation agriculture. [ABSTRACT FROM AUTHOR]

Pennisetum purpureum's cultivars are the predominantly grasses for cutting in Cuba, and I the last years, it use has been incremented particularly in areas under irrigation mainly in areas of small farmers; taking into account the last considerations and in order to obtain basic information for irrigation planning and management in this grass in the province of Granma it was carry out this work where were compared the cultivars Cuba CT-115, CT-169 y CT-607 under different irrigation levels. The experimental area was located in the Grass and Forages Experimental Station Experimental “La Pitucha" (Agricultural Research Institute ¨Jorge Dimitrov¨), using the central line sprinkler design; the three cultivars were planted perpendicular to the sprinkler central line in plots 15 m long and 6 m wide replicates four times. The diameter of the sprinkler used allowed establishing four different irrigation gradients decreasing in the direction far away from the sprinkler; the plots were cutting every 60 days for a total of 5 cuts in the experimental year. During the dry season, cv CT-169 averaged 2.4 ton dry mater, and this yield was significantly higher than cvs CT-115 and CT-607 that yields 20% and 60% less respectively; in the lowest irrigation treatments there not were differences in yield between the cultivars tested. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Grain sorghum production in Cuba has been an increased tendency in the last ten years, to this has contributed the crop´s high yield potentiality, high adaptation capacity, water stress tolerance and an increase in the demand for animal feedstuff. The municipality of Los Palacios, localized in the Pinar del Rio province (west of Cuba) is an area characterized for its high grain production, mainly rice, dry beans, maize and in the last years sorghum. Grain sorghum in this area is cultivated mainly under irrigation; the lack of information about sorghum´s water requirements in the region is one of the most important problem in order to obtain the best yield from irrigated areas and higher values of water productivity as well as a better performance of the irrigations systems. Taking into account these demands, it was developed the present work were it was estimated the sorghum´s water requirements using FAO CropWat 8.0 program for three different planting time and three rainfall probabilities, in a Ferrasol (Ferralítico cuarcítico amarillento lixiviado, accordingly Cuban´s soil classification) typical of the area. Crop evapotranspiration (Etc) varied between 221,2 mm (less value) during November-February planting date and 20% rainfall probability; during June-September planting date ETc was 419,5 mm (highest value) at 80% rainfall probabilities; the highest irrigation demand was 326 mm when the crop demand 12 irrigation during April-July planting date with and 80% rainfall probability. [ABSTRACT FROM AUTHOR]

In this work, it was study during two plantation dates the response of grain sorghum to the combination of three irrigation time (irrigation at 85%, 75% of soil field capacity and only irrigation during germination time) and three levels of nitrogen fertilizer (33, 68 y 100 kg N ha-1) in a ferrasol. During June-September plantation´s time, the grain yield, when sorghum was irrigated at 85% field capacity, was only 9% high than the other treatments; while the increase in N level from 33 to 100 kg N did not increase the yield. During the plantation time December-April, the best yield was obtained with the combination of irrigation at 75% field capacity and with the low nitrogen level, irrigation at 85% percent during this period yielded 5 and 25 % more grain compared with 75% field capacity and irrigation only during germination. The best yield was obtained with the application of 33 Kg N ha-1 and it was superior in 9 and 6% as compared with 68 and 100 kg N respectively. In both planting times, the highest ETc was obtained when it was irrigated a 85% field capacity and 33 Kg N fertilization with values of 490,8 and 412,7 mm for June-September and December-April planting´s time. In both planting date, water consumption increase linearly with the quantity of irrigation water applied. [ABSTRACT FROM AUTHOR]

In these work, it is analyzed the influence of different factor as variety, planting date and soil type in the water response of main agricultural crop based using available information obtained from more than 100 field experiments due in Cuba; its include 20 crops, 6 different soils types and water management and it was also used the water yield functions obtained in antecedent studies. The variety factor was analyzed for corn and pepper comparing results of yield water functions for different varieties in the same type of soil, Ferrasol. The planting date factor was analyzed comparing results for soybean in summer, spring and winter season, for sorgo crop in summer and winter season and for pepper in november- april and march-may planting date. The soil factor was analyzed comparing results in pepper crop for two soil type, Ferrasol and Aluvial soil and in the sweet potato in three soil type, Ferrasol, Aluvial and Pardo soils. The analysis showed evidences that although it was found particulars differences between varieties, plant season and soil types considering the absolutes values of yield and evapotranspiration or water applied, the response model was similar in all conditions studied indicating in this way, that it is possible to obtain a general model for different conditions where the model is applicable. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In Cuba, the major quantity of areas affected by waterlogging and salinity are occupied with vertisols, this soils cover around 30 % of the potential cultivated areas in the country. The particular feature of this soil to contract and swelling with the variations in soil water content, due to the particular type of clay they content (smectites), pose a great constraint for is agriculture use without irrigation as well as under irrigation. The managing of vertisols following methods and techniques used in non-dilatable soils may conduce to a rapid soil degradation and a failures in agriculture production. Taking into account the research work carry out for different Cuban's research institution in the 80´s, this paper expose some of the most important results and emphasize in the vertisols water related properties' in order to obtain the best result when this typical soils properties' are taking into account in vertisol management. [ABSTRACT FROM AUTHOR]

Rainfall excess during the rainy season is the main cause of soil waterlogging in Cuba. In areas with poor soil drainage, surface drainage is the best solution for cropping during the rainy season, but for an adequate drainage system design, it is necessary to know the required time to evacuate the excess rainfall before the crop is affected by waterlogging in soils. Data from different experiments carry out in Cuba, were if was measured the effects of the numbers of days with excessive soil moisture on yield in different crops; where adjusted to a piecewise linear model similar to one developed for Gupta et al (1992) in India. Adjusting the model, it was find that there is not yield declined for a few initial days of submergence, beyond this period, if submergence continue, there would be linear decline in yield. The unknown parameters in the model are optimum yield, threshold time and the slope which represent the percent yield reduction per day of additional submergence beyond the threshold. The model worked well in the crops selected (sugar cane, black bean, soya bean, potatoes, star grass and king grass); in some of them like black bean and potatoes, the threshold value was cero or very closed; the highest percent values of yields reduction in relation with the number of submergence days were 34,3, 23,2 and 16,3 for potatoes, black bean and soya bean respectively and lowest were star grass, sugar cane and king grass. The prosed model permit to calculate the drainage requirements and the economic evaluation of crop submergence and the economic value of the investment to do in drainage; it is recommended to continues the research and to extend the model to others important crops in the country like corn, sorghum, sunflowers and others that are planted in soils susceptible to submergence. [ABSTRACT FROM AUTHOR]

Net water requirements of agricultural crops are important data necessary in the calculation of the demand of water for the agriculture; hence, it is indispensable to have reliable and up-to-date data to carry out a balance of water requirements to satisfy the necessities of the agriculture and at the same time to use the water judiciously. The present work upgrades the effective water requirements used for more than 15 years, and at the same time describes the bases of this upgrade and proposes rules to be used in the future on the researches in this field. [ABSTRACT FROM AUTHOR]

Detailed planning of water resources needed for the first irrigation of rice is a pending subject in the updating process of irrigation systems for this crop. To answer this need, the present work introduces a methodology based on the integration of a procedure for irrigation design in rice terraces along with a geographic information system (GIS). Parameters for water resources planning are obtained from algebraic operations between maps and the detailed quantification and resources needed for each field. Its application to a group of rice fields allowed to obtain necessary water volumes and discharges for the first irrigation of rice and, from these, to evaluate functionality of the existing irrigation system. [ABSTRACT FROM AUTHOR]