Total Irrigation Research Articles

Production Techniques for Strawberry Plugs in West-central Florida

Florida-produced strawberry (Fragaria ×ananassa) plug transplants (SP) are a potential alternative to bare-root transplants (BR). The adoption of this technology could represent a reduction in water usage for plant establishment and potentially higher early yield, as SP may establish more quickly than BR. Thus, the objective of this study was to evaluate the effect of time in nursery and tray sizes, on early and total strawberry yield for Florida-produced SP for ‘Florida Radiance’, ‘Strawberry Festival’, and Sweet Sensation® ‘Florida127’. Runners from Florida-produced mother plants were collected in mid and late August from 2012 to 2015. SP were grown for either 4 or 6 weeks according to the treatment and established in 30-, 40-, 50-, and 72-cell trays, and compared with BR (control). Additionally, strawberry tips from California were evaluated for SP production. BR consistently had higher early yield than SP, ranging from 36% to 91%, between 2012 and 2016. SP produced the same or higher total yield than BR. Florida-produced SP should be grown for 4 weeks before field transplanting in 50-cell trays based on the results of this study. Furthermore, there was no difference between California and Florida tips for total yield. In all seasons, all SP were established with 20% of the total irrigation water used for the BR. Thus, SP could potentially result in water savings of almost 820,800 gal/acre per season, but the early yield of SP would need to be improved to match BR performance.

Determining Irrigation Depths for Soybean Using a Simulation Model of Water Flow and Plant Growth and Weather Forecasts

A new scheme to determine irrigation depths using a two-point of predicted cumulative transpiration over irrigation interval is presented. Rather than maximizing water use efficiency, this scheme aims to maximize net income. The volumetric water price is considered to give farmers an incentive to save irrigation water. A field experiment for soybeans was carried out in the Arid Land Research Center, Tottori University, Japan in 2019. The total irrigation amount yield and net income by the proposed scheme were compared to those by a tensiometer-operated automated irrigation. The scheme could save irrigation water by 16% with a yield increment of 20%; resulting in a 22% increase in net income compared to the automated irrigation. The model simulated the volumetric water content in the effective root zone of the plant in fair agreement. These results indicate the effectiveness of the proposed scheme that may replace an automated irrigation system even considering uncertainty in weather forecast to determine irrigation depth and secure investment costs.

Quantitative Assessment of the Impact of Human Activities on Terrestrial Net Primary Productivity in the Yangtze River Delta

The continuous growth of the economy and population have promoted increasing consumption of natural resources, and raised concerns regarding the upper limits of the terrestrial ecosystems with biomass accessible for humanity. Here, human appropriation of net primary production (HANPP) was employed to assess the influence of human activities on terrestrial net primary production (NPP), and a detailed method was introduced to simulate the magnitude and trends of HANPP in the Yangtze River Delta. The results showed that the total HANPP of the Yangtze River Delta increased from 102.3 Tg C yr−1 to 142.2 Tg C yr−1, during 2005–2015, with an average of 121.3 Tg C yr−1. NPP changes induced by harvest (HANPPharv) made the dominant contribution of 79.9% to the total HANPP, and the increase of HANPPharv in cropland was the main driver of total HANPP growth, which was significantly correlated with the improvement in agricultural production conditions, such as total agricultural machinery power and effective irrigation area. The proportion of HANPP ranged from 59.3% to 72.4% of potential NPP during 2005–2015 in the Yangtze River Delta, and distinguishable differences in the proportions were found among the four provinces in the Yangtze River Delta. Shanghai had the largest proportion of 84.3%, while Zhejiang had the lowest proportion of 32.0%.

Assessment of drought disaster risk in Boro rice cultivated areas of northwestern Bangladesh

Drought risk has become a major threat for sustaining food security in Bangladesh; the particularly northwestern region of Bangladesh. The objective of the study is to assess drought disaster risk on Boro paddy cultivated areas of northwestern Bangladesh using drought disaster risk index (DDRI) model. The sensitivity of Boro paddy to droughts during crop-growing seasons and irrigation recoverability were employed to reflect vulnerability condition. Moreover, the threshold level of the standardized precipitation evapotranspiration index (SPEI) was applied to evaluate the drought hazard on Boro paddy cultivated areas in the northwestern region of Bangladesh. The probability density function (PDF) was used to show the threshold level of drought hazard. The results show that drought hazard is comparatively severe in Ishardi area compared to other northwestern regions of Bangladesh. The drought disaster risk is higher in Ishardi and Rajshahi areas than Rangpur and Dinajpur areas. Although Ishardi area is more prone to high drought risk, at the same time, the recoverability rate is also quicker than any other areas. The relationship between Boro rice yield rates and drought disaster risk is insignificant. The average Boro yield rates during the period of 1976 to 2016 are 19% for Ishardi and Rajshahi areas, 20% for Rangpur and Dinajpur areas and 21% for Bogra respectively according to the total irrigation area. The outcomes of the study can aid to adopt drought condition under changing the climate and also provide guidance for future drought mitigation in the northwest region of Bangladesh.

Can we beneficially reuse produced water from oil and gas extraction in the U.S.?

There is increasing interest in beneficial uses of large volumes of wastewater co-produced with oil and gas extraction (produced water, PW) because of water scarcity, potential subsurface disposal limitations, and regional linkages to induced seismicity. Here we quantified PW volumes relative to water demand in different sectors and PW quality relative to treatment and reuse options for the major U.S. shale oil and gas plays. PW volumes from these plays totaled ~600 billion liters (BL, 160 billion gallons, Bgal) in 2017. One year of PW is equal to ~60% of one day of freshwater use in the U.S. For these plays, the total irrigation demand exceeded PW volumes by ~5× whereas municipal demand exceeded PW by ~2×. If PW is reused for hydraulic fracturing (HF) within the energy sector, there would be no excess PW in about half of the plays because HF water demand exceeds PW volumes in those plays. PW quality can be highly saline with median total dissolved solids up to 255 g/L in the Bakken play, ~7× seawater. Intensive water treatment required for PW from most unconventional plays would further reduce PW volumes by at least 2×. Desalination would also result in large volumes of salt concentrates, equivalent to ~3000 Olympic swimming pools in the Permian Delaware Basin in 2017. While water demands outside the energy sector could accommodate PW volumes, much lower PW volumes relative to water demand in most regions would not substantially alleviate water scarcity. However, large projected PW volumes relative to HF water demand over the life of the play in the Permian Delaware Basin may provide a substantial new water source for beneficial use in the future. Large knowledge gaps in PW quality, lack of appropriate regulations, and economic factors currently preclude beneficial uses outside the energy sector in most regions.

Irrigation Water Potential and Land Suitability Assessment in Kurfa Chele-Girawa Watershed, Wabe Shebelle River Basin, Ethiopia

Assessing available water and land for irrigation are important for planning their use. In the watershed, stream flows from some of the rivers are not known and potential irrigable areas have not been identified. By delineating watershed boundary, irrigation suitability factors such as soil type, slope, land cover/use, and distance from the water supply were classified based on the FAO guideline for land evaluation in to S1, S2, S3 and N suitability classes independently. The irrigation potential suitability analysis of soil, slope, land cover/use and Euclidean distance indicates that 55.1 %, 95.6 %, 88.6% and 93.7% respectively are in the range of highly to marginally suitable. By weighted overlay analysis, total surface irrigation suitability potential of the study area is 54.6%, from this, the potential irrigable land obtained by multi_ criteria analysis has 45.9%. The total available flow above abstraction site is 335.7m3/s or 2.9-million-meter cube (MMC) annually.

Mineral nutrients needs of cucumber and its yield in protected winter cultivation, with HPS and LED supplementary lighting

The objective of the study was to evaluate yield, mineral nutrients uptake and nutrient demands of cucumber plants in winter cultivation with HPS and LED supplementary lighting. The experiment was carried out in the three variants: 1) HPS - top light only; 2) HPS + LED - top light + 2 lines of LED inter-row light; 3) LED + LED - top LED + 2-line LED inter-row light. In these variants the same PAR intensity level, of about 320 μmol m−2 s−1 (PPFD), was provided. Midi-cucumber parthenocarpic cultivar ‘Svyatogor’ F1, of high shade tolerance and 18–22 cm fruit lenght, was grown for 17 weeks during winter, in mineral-rock slabs. The plants were trained on a single stem up a string, according to the ‘high wire system’ method. Number and weight of every-day harvested fruit were determined. On the basis of monitoring, content of macro- and micro-elements in drip and drain solutions that was undertaken during every two-week period and constant monitoring of total daily drip irrigation quantity with nutrient solution per one plant, as well as total daily drain of the nutrient solution, the daily uptake of nutrient solutions and nutrients per one plant was calculated. The nutrient status of the plants was determined by leaf samples analysis performed for the younger, upper 3rd–5th leaves, as well as for the older, 10th–12th, lower leaves. Cucumber plants were characterized by stable yield and showed high fruit yield of very good quality. The highest yield was found for the plants grown with supplementary lighting with LED + LED. Leaves from the plants grown with the standard HPS top lighting showed faster senescence than the leaves of the plants grown with inter-row lighting. This is evidenced by a higher concentration of Ca, Mg, S, Mn and B ions, together with a lower concentration of K ions, in 10th–12th leaves in the plants grown with the standard HPS top lighting, compared with the plants grown with the HPS + LED lighting, as well as with the LED + LED lighting. The plants grown with the inter-row lighting showed a higher nutritional demands than the plants grown with the standard HPS top lighting. Parallelly used LED top lighting resulted in a higher and more stable yield, compared to standard HPS lighting conditions.

Impact of Irrigation and Fertigation on the Yield and Quality of Sugar Beet (Beta vulgaris L.) in a Moderate Climate

In Poland, under conditions of the moderate climate and transition between maritime and continental climates, the average rainfall totals of the growing season are in the range of 350–400 mm; however, they are distinguished by great temporal and spatial variability. Climatological studies demonstrate that the drought frequency is approximately 30%. Therefore, under such conditions, irrigation has a supplementary and intervention nature and is applied only when dry periods occur. The aim of this study was to determine the impact of sprinkler irrigation and increased nitrogen fertilization on the yield and quality of sugar beet roots and yield of sugar. The average increase of the yield under irrigation was 18.1 t·ha−1 which constituted a 22.8% increase in the yield. Furthermore, there was a marked tendency of a higher sugar content in the roots of irrigated plants. The absolute, relative, and unit average sugar beet root yield increases obtained under the influence of sprinkler irrigation and the lack of a significant diversity in the sugar content in roots confirm that irrigation contributed to an appropriate pace of plant growth and development. The increased rate of nitrogen fertilization (N2) of 160 kg N·ha−1 plus an additional 40 kg N·ha−1 resulted in the significantly greater root yields compared to the control (N1) (160 kg N·ha−1), i.e., an average of 7.6 t·ha−1 (9%). Based on the crop-water production function, the maximum root yields were obtained for the N1 rate at a total precipitation and irrigation amount of 382 mm, compared with 367 mm for the N2 rate.

Water requirement of rice crop using CROPWAT model for Dehradun district, Uttarakhand

Management of water resources with optimal utilization results in fulfilling the constraint of inadequate water availability. Determination of crop water requirement is the first step in planning and effective utilization of irrigation water which curtaining the impact developed due to water stress condition. In the present study crop water requirement (CWR) and irrigation requirement was computed for rice in Dehradun district using CROPWAT simulation software by taking into account different local climatic parameter which influencing reference crop evapotranspiration (ET0) and thus affecting crop production. Penman–Monteith method was used to calculate ET0 and the United States Department of Agriculture (USDA) soil conservation method was used to estimate the effective rainfall. The ET0 varied from 1.43 (January) to 5.28 (May) mm/day and annual mean was 3.1 mm/day. The average annual rainfall value was 1718 mm and out of which 977.3 mm was effective rainfall. The crop water requirement and net irrigation water requirement (NIR) for rice crop was estimated to be 559.5 mm and 288.7 mm, respectively. The values of CWR and NIR were maximum in June and minimum in October. The net scheme irrigation requirement was scheduled to be maximum in June (190.6 mm/month), minimum in October month and zero in the month of July, August and September. The actual irrigated area was found to be 18.92 km2 for which net irrigation demand was maximum in the month of June (3.61 MCM) followed by October month (0.12 MCM). Total net irrigation demand for actual irrigated area was 5.47 MCM. The computation of crop water requirement, NIR, and total net irrigation demand using CROPWAT has proved to be an effective tool for proper management of water resources in water stress condition.

The influence of the final irrigation protocol on the efficiency of root canal cleaning

Introduction/Objective. Irrigation has an important role in root canal cleaning and its efficiency depends on the type of irrigants, the amount, the technique and the irrigation protocol. The aim of this work was to estimate the efficiency of cleaning of the canal walls by using scanning electron microscope analysis after the instrumentation by rotary NiTi instruments with the use of three different irrigation solutions and two final irrigation protocols. Methods. Sixty extracted human incisors were divided into two groups after the rotary instrumentation with the iRace instruments. In both groups, the same amount (1.5 ml) of three solutions (2% sodium hypochlorite solution, 2% chlorhexidine solution, and 10% citric acid solution) and total final irrigation time (90 seconds) was the same. The final irrigation in the first group was accomplished using the technique of continuous irrigation and in the second group it was done using the intermittent protocol. The roots were cut longitudinally and analyzed by thirds (coronal, middle, and apical) on a scanning electron microscope (JSM 6460LV, JEOL Ltd., Tokyo, Japan) with 1,000? magnification. Results. The most efficient cleaning of the root canal walls in both groups was seen after the use of citric acid with the intermittent protocol of the final irrigation (90.7% clean walls), while the least efficient was the final irrigation by chlorhexidine with continuous irrigation (80.3%). The most efficient cleaning of the canal walls in both groups was observed in the coronal third and the largest amount of the smear layer in the apical third. Conclusion. The most efficient cleaning of the canal was achieved by the use of citric acid and the intermittent protocol of the final irrigation. In all tested solutions, the intermittent protocol of irrigation was more efficient than continuous irrigation.

Salt leaching process in coastal saline soil by infiltration of melting saline ice under field conditions

Freezing saline water irrigation (FSWI) in winter has been shown to be an effective way to reclaim heavy saline soils. In this four-year experiment, the salt leaching process during saline ice melting and infiltration after FSWI was investigated. Saline water was frozen in saline ice on top of soil after irrigation. Over 70 or 80 days of ice melting and infiltration, ice and soil samples were taken at 10-day intervals to quantify the soil salt leaching process. The results showed that salt leaching mainly occurred in the initial 30 days after irrigation (DAI); approximately 72% of the total salt reduction was the result of salt migrating out of the 0 to 20 cm soil layer. Furthermore, in this period, the amount of salt that leached out of the 0 to 20 cm soil layer with meltwater was greater than the total salt from the irrigation water. Approximately 15% of the total salt reduction in the 0 to 20 cm layer occurred from 60 to 80 DAI; in this period, the infiltrating meltwater accounted for more than 30% of the total irrigation water, and the electrical conductivity of the meltwater was below 4.5 dS m−1. After the meltwater had infiltrated the soil completely, the electrical conductivity of saturation paste (ECe) in the 0 to 20 cm layer for FSWI was below 4.3 dS m−1, significantly lower than the ECe of 16.7 dS m−1 of the nontreated soil. These results indicated the soil salt leaching was mainly determined by the melting process of saline ice under the FSWI treatment.

Estimating Water Balance and Identifying Crops for Sustainable Use of Water Resources in the Bundelkhand Region of India

HighlightsA crop suitability index was constructed for the Bundelkhand region of India.The cropping pattern in the region has shifted from cereals to oilseeds and pulses.Nearly 33% more water is needed to meet the total irrigation water requirement of the region.Pearl millet, sesame, and soybean were found to be the most suitable crops for sustainable use of water resources. ABSTRACT.The Bundelkhand region of India is characterized by acute shortages of water due to recurrent failures of the monsoon. This study estimated the water availability, water requirement, and water deficit in the Bundelkhand region using geographic information system (GIS) data. The study identified suitable crops that can be promoted for sustaining the water resources in the region. Total water availability is estimated to be 17.48 billion cubic meters (BCM), of which 91.3% is available for irrigation. The irrigation water deficit is estimated to be 5.31 BCM, which is 1/4 of the crop water requirement. Farmers in the region give high priority to irrigation of water-guzzling cereal crops instead of pulses and oilseed crops, which have lower water requirements. A crop suitability index revealed that pearl millet, sesame, and soybean are the most suitable crops for sustainable use of water resources in the region. An optimum cropping plan to allocate existing land and water resources, coupled with efficient modern technology such as direct-seeded rice, micro-irrigation, etc., can be the best solution to sustain the natural resources and the income of farmers in the study region. Keywords: Bundelkhand, Crop suitability index, Geographical information system, Water.

Planning water-energy-food nexus system management under multi-level and uncertainty

Abstract In this study, a multi-level interval fuzzy credibility-constrained programming (MIFCP) method is developed for planning the regional-scale water-energy-food nexus (WEFN) system. MIFCP can not only deal with uncertainties expressed as interval parameters and fuzzy sets, but also handle conflicts and hierarchical relationships among multiple decision departments. The MIFCP approach is then applied to planning the WEFN system of Henan Province, China. Solutions of three different decision targets in various hierarchy levels, five scenarios with different decision makers’ objectives and five credibility levels toward different necessity degrees are examined. Several findings in association with various planting structures, water resources demand, energy consumption, fertilizer and pesticide utilizations and system benefits are achieved. Results reveal that the future total irrigation water can decrease by 1.49% from years 2020–2025. Results also disclose that the total cultivated area can change by 1.91% owing to the variation of fertilizer and pesticide change. Compared to single level programming (SLP) and bi-level programming (BP) approaches, the MIFCP-WEFN model can help decision-makers identify the optimal agricultural water resources management schemes by means of the leadership of water resources managers as well as the feedback of two diverse followers (i.e. energy managers and agricultural managers).

Alfalfa canopy water interception under low-pressure sprinklers

Canopy water interception is an important factor in water use efficiency analysis and sprinkler-based fertigation technique development. In the present study, alfalfa canopy water interception and its influence factors were assessed under low wind conditions. The canopy interception capacity for three growth stages of alfalfa (S1, early vegetative stage; S2, late vegetative stage; S3, bud stage) were measured under two types of low-pressure spray sprinklers. The dynamics of canopy interception and interception ratio with irrigation depth were also observed. The total irrigation depth for all measurements was around 8 mm. A weight-based canopy interception measurement device was installed outdoors and integrated with a 20-psi sprinkler at 1 m above the canopy. The alfalfa canopy interception first increased rapidly with irrigation depth, but then stabilized and reached canopy interception capacity (Im). The minimum irrigation depths to achieve the Im values were 2 mm, 3 mm, and 4 mm at the S1, S2 and S3 stages, respectively. Im increased significantly across growth stages, and ranged from 0.46 mm to 1.49 mm. Interception ratio decreased gradually as irrigation depth increased. With an approximately 8-mm total irrigation depth, interception ratio ranged from 5.27 % to 17.59 % over all growth stages. Water application rate had no effect on Im, and Im decreased with droplet diameter. Generally, Im was higher and reached more quickly with the R3000 sprinkler compared to the D3000 sprinkler. Fresh weight, plant height, and LAI of alfalfa had significant positive correlations with canopy interception capacity, and a quadratic regression model was developed with using plant height as a factor. This study provides valuable and basic information for irrigation schedules and fertigation in alfalfa cultivation.

Event‐based deep drainage and percolation dynamics in Vertosols and Chromosols

AbstractThe quantification of percolation processes and deep drainage rates in cracking clays is challenging due to the existence of multiple flow pathways, including desiccation crack networks, and the effect of variability in antecedent soil moisture and rain event properties. While most previous research on this topic focuses on long‐term average rates, this study focusses on inter‐event dynamics. The study uses data from soil moisture sensors distributed vertically down 4 m profiles of Vertosol and Chromosol soils across 13 sites over an area of approximately 20 km2. The objectives were to estimate the temporal and spatial variability of deep drainage rates and to investigate the effect of antecedent soil moisture conditions and rain event properties on deep drainage rates and percolation dynamics. 35 deep drainage events over a 40‐month period contributed 78 % of the total deep drainage of 254 mm at 4 m depth. Average deep drainage estimates were about 15 % (ranging from 0 – 80 % between sites) of total rainfall and irrigation in the Vertosol and 8% (0 – 24 %) in the Chromosol. The event water travel times at 4 m depth were 0.25 – 38 hr and 14 – 39 hr in the Vertosol and Chromosol respectively. The event deep drainage rates averaged across sites were associated with event rainfall volumes (linear regression R2 = 0.40), with the effect of antecedent conditions evident only when looking at inter‐site differences. The percolation response time was strongly associated with higher rainfall intensities (R2 = 0.33) with no evidence from the linear regression of an antecedent moisture effect.

Comparison of water use efficiency, profitability and consumer preferences of different rice varieties in Punjab, Pakistan

Due to rapid population growth, water scarcity and food insecurity have become the major problems for Pakistan. Therefore, the efficient utilization of limited resources such as water is very important in agriculture. Paddy or rice—Pakistan’s second most important cereal and staple crop—is a water-intensive crop. The present study aims to estimate the water use efficiency, profitability, and consumer preferences of different paddy varieties such as basmati, coarse and hybrid rice in Punjab. To this end, we collected field survey data from 330 rice growers in six districts of the rice–wheat zone of Punjab. The results showed that basmati rice is more profitable due to low production cost and higher prices. Although the number of irrigations applied to basmati rice and coarse rice was higher than that of hybrid rice, the amount of water applied to hybrid rice was the highest. Therefore, the total irrigation cost of hybrid rice is higher, while the coarse rice has higher water productivity. Furthermore, the economic productivity of water applied to basmati rice and coarse rice is higher than that of hybrid rice. Consumer preferences based on data from 150 consumers indicate that basmati rice is a favorite of consumers and that hybrid rice is the least popular. These results imply that it is better to grow basmati or coarse rice than hybrid rice due to water shortages in Pakistan. Another approach is to replace these varieties with alternative crops such as corn and soybeans that require less water.

Use of Remote Sensing and Geographic Information Systems in Irrigation Performance: A Case Study of Atabey Irrigation Scheme

In this study, the irrigation
 performance of Atabey Irrigation Scheme was assessed by making use of Remote
 Sensing (RS) and the Geographic Information System (GIS). For this purpose, the
 crop pattern maps of the scheme were generated by the help of the supervised
 classification method with the RapidEye satellite data of 2012 concerning the
 study area by employing the RS techniques, whereas the canal maps of the scheme
 were generated by the help of the techniques of the Geographic Information
 System. By the help of these data, the monthly water supply ratios – one of the
 performance indicators – were computed. A total of 24 crop classes, 10 of which
 were in the irrigated area corresponding to about one-third (5,239.75 ha;
 33.72%) of the total area but the remaining 14 of which were in the
 non-irrigated (rainfed agriculture) area corresponding to about two-thirds
 (10,299.74 ha; 66.28%) of the scheme area, were determined as a result of the
 crop pattern classification. The total irrigation water requirement for Atabey
 irrigation scheme was calculated as 42,618 m3 minimum and 5,647,246
 m3 at the maximum between April and October. The Relative Water
 Supply (RWS) in the months concerned ranged from 28.16 to 2.39 and the average
 in 2012 was calculated as 3.25. The assessment, collection, operating and
 maintenance expenses of the scheme and, by the help of these data, its fee
 collection and financial efficiency ratios were calculated. The fee collection
 ratio was found as 88.12% and the financial efficiency ratio as 1.42 at the
 scheme in 2012.

Estimation of the Optimal Use of Irrigation Water in Production of Lettuce – An Economical Approach

The lack of data, information and studies examining the economic issues which related to crop water consumption are the main obstacles facing decision makers, legislators and farmers to optimize the use of water for agricultural purposes. This study aims to determine the optimal quantity of irrigation water for lettuce (lactuca sativa L.), which is a crop that does not have local data on its behavior of water consumption. To achieve the goals of the study, field experiment was conducted under trickle irrigation condition at the Tripoli Center of Agricultural Research during winter season of 2017.Four levels of irrigation water 130 mm, 195 mm, 260 mm and 320 mm were applied. These levels were selected based on the water requirements as calculated from Penman- Monthieth -FAO 1998 equation to represent 50, 75, 100, and 125% of total irrigation water required by lettuce crop, respectively. A second degree polynomial equation was fitted (R 2 = 0.64) for production function (yield in ton/ha versus. applied irrigation water in m3/ha). The results revealed that the increase in the quantity of irrigation water led to a higher yield of lettuce to a specific point and then the production rates decreased. According to the water price, the results of economical analysis indicated that the optimal quantity of irrigation water estimated of the lettuce which achieved the optimal productivity was found at 2506 m3 / ha. Many studies and researches on several crops must be conducted under field conditions in order to reach the optimal approach that ensures achieving high yield production through optimal use of limited water resources

UTILIZAÇÃO DA ÁGUA RESIDUÁRIA TRATADA POR RADIAÇÃO SOLAR NA IRRIGAÇÃO DA CULTURA DE CEBOLINHA

UTILIZAÇÃO DA ÁGUA RESIDUÁRIA TRATADA POR RADIAÇÃO SOLAR NA IRRIGAÇÃO DA CULTURA DE CEBOLINHA
 
 
 MARIANA ALEXANDRE DE LIMA SALES1 E RODRIGO MÁXIMO SÁNCHEZ ROMÁN2
 
 1 Doutora em Agronomia: Irrigação e Drenagem. Rua Heleni de Souza Costa, 41 – Jardim Ypê, 18.608-710, Botucatu-SP, Brasil. mal_sales@hotmail.com
 2 Departamento de Engenharia Rural, Faculdade de Ciências Agronômicas, Universidade Estadual Paulista (UNESP) Campus de Botucatu. Fazenda Experimental Lageado, Avenida Universitária, nº 3780, Altos do Paraíso, CEP: 18610-034, Botucatu – SP. Brasil. rodrigo.roman@unesp.br.
 
 
 1 RESUMO
 
 Visto que a agricultura é a atividade que mais utiliza água, há a necessidade de reutilizar água nessa prática. Este trabalho teve como objetivo avaliar a influência da aplicação de diferentes porcentagens de água residuária tratada por radiação solar (AR-TRS) na cultura da cebolinha ‘todo ano’ e quantificar E. coli na cultura. O experimento foi conduzido no Departamento de Engenharia Rural da FCA/UNESP, Botucatu (SP). O delineamento estatístico adotado foi o casualizado, com cinco repetições e cinco tratamentos, 0, 25, 50, 75 e 100% de AR-TRS na lâmina total de irrigação, completando os tratamentos com, respectivamente, 100, 75, 50, 25 e 0% de água de abastecimento da FCA (AAF). Os resultados demonstram influência da ARD-TRS nos parâmetros estudados, altura da planta, número de talos, diâmetro do maior talo, número de perfilhos, diâmetro do maior perfilho, diâmetro da touceira, média da matéria fresca e seca. Em E. coli, que não foi verificada influência, observando sim, uma provável contaminação cruzada numa amostra. Foi concluído que a utilização de ARD-TRS é bem-vinda, pois traz incrementos produtivos para a cultura, além de seus valores de E. coli estarem dentro dos padrões definidos pela Organização Mundial de Saúde.
 
 Palavras-chave: Allium fistulosum L, SODIS, coliformes totais, E.coli.
 
 
 SALES, M. A. L.; SÁNCHEZ-ROMÁN, R. M.
 USE OF WASTE WATER TREATED BY SOLAR RADIATION IN IRRIGATION OF SCALLION CULTURE
 
 
 2 ABSTRACT
 
 Since agriculture is the activity that consumes most water, there is a need to reuse water in this practice. The objective of this work was to evaluate the influence of the application of different percentages of wastewater treated by solar radiation (AR-TRS) in scallion 'all-year' culture and to quantify E. coli in the culture. The experiment was conducted at the Department of Rural Engineering of FCA / UNESP, Botucatu-SP. The statistical design was randomized with five replicates and five treatments, 0, 25, 50, 75 and 100% of AR-TRS in the total irrigation depth, completing treatments with 100, 75, 50, 25 and 0% of supply water (AAF). The results demonstrate the influence of ARD-TRS in the parameters studied: plant height, number of stalks, diameter of the largest stem, number of tillers, diameter of the largest till, diameter of the clump, mean fresh and dry matter, except for E. coli, which showed no influence, but a possible cross-contamination in a sample was observed. In conclusion, the use of ARD-TRS is welcome because it brings productive increases to the culture, moreover, its E. coli values are within the standards defined by the World Health Organization.
 
 Keywords: Allium fistulosum L, SODIS, total coliforms, E. coli.

Analysis of climate change effects on crop water availability for paddy, wheat and berseem

Climate change has been a serious concern in the 21st century and mitigation strategies on its effects are less researched. The increase in temperature and changes in rainfall have forced researchers to ponder over reducing the wastage of fresh water. This paper deals with the rain water availability and the crop evapotranspiration (ETc) changes occurring and projected to occur over a time period of fifty years. Three major crops, paddy, wheat and berseem fodder were considered for three locations. Observed data and forecasted data for precipitation and temperature was obtained from India Meteorological Department and Can Esm2 model respectively. The Mann–Kendall (MK) test and the Thiel-Sen's Slope estimator (TSS) test were applied on the crop stage wise aggregated rain water available and the ETc to analyze the effects of climate change. In addition to the above study, the historical and projected means of crop period wise aggregated effective rainfall, total net irrigation requirement and total crop water requirement for a range of dates of sowing/transplanting for the above mentioned crops and locations were analyzed. It was seen by the analysis that the rainwater availability is seen to decrease and the temperatures increase with a delay in the sowing dates in the future scenarios causing an increase in the crop water requirements. Suitable shifting of the crop sowing or transplanting dates is seen to aid to better exploit the available rainwater and minimize the irrigation application.