Plant Water Consumption Research Articles

Elevated CO2 Modulates Plant Hydraulic Conductance Through Regulation of PIPs Under Progressive Soil Drying in Tomato Plants.

Increasing atmospheric CO2 concentrations accompanied by abiotic stresses challenge food production worldwide. Elevated CO2 (e[CO2]) affects plant water relations via multiple mechanisms involving abscisic acid (ABA). Here, two tomato (Solanum lycopersicum) genotypes, Ailsa Craig (AC) and its ABA-deficient mutant (flacca), were used to investigate the responses of plant hydraulic conductance to e[CO2] and drought stress. Results showed that e[CO2] decreased transpiration rate (E) increased plant water use efficiency only in AC, whereas it increased daily plant water consumption and osmotic adjustment in both genotypes. Compared to growth at ambient [CO2], AC leaf and root hydraulic conductance (Kleaf and Kroot) decreased at e[CO2], which coincided with the transcriptional regulations of genes of plasma membrane intrinsic proteins (PIPs) and OPEN STOMATA 1 (OST1), and these effects were attenuated in flacca during soil drying. Severe drought stress could override the effects of e[CO2] on plant water relation characteristics. In both genotypes, drought stress resulted in decreased E, Kleaf, and Kroot accompanied by transcriptional responses of PIPs and OST1. However, under conditions combining e[CO2] and drought, some PIPs were not responsive to drought in AC, indicating that e[CO2] might disturb ABA-mediated drought responses. These results provide some new insights into mechanisms of plant hydraulic response to drought stress in a future CO2-enriched environment.

The impact of land use on future water balance - A simple approach for analysing climate change effects

Regional climate change projections for Europe agree in predicting a statistically significant warming in all seasons. The most significant climate change effect is its impact on water cycle through altering precipitation patterns and evapotranspiration processes at multiple scales. The anticipated changes in the distribution and precipitation amounts together with continuously increasing temperatures may induce a higher rate of water consumption in plants, which can generate changes in soil moisture, groundwater, and the water cycle. Thus, climate change can cause changes in the water balance equations structure. A Thornthwaite-type monthly step water balance model was established to compare the water balance in three different surface land cover types: (i) a natural forested area; (ii) a parcel with mixed surface cover; (iii) an agricultural area. The key parameter of the model is the water storage capacity of the soil. Maximal rooting depth of the given area is also determinable during the calibration process using actual evapotranspiration (AET) and soil physical data. The locally calibrated model was employed for assessing future AET and soil moisture of selected land cover types using data from four bias-corrected regional climate models. The projections demonstrate increasing actual evapotranspiration values in each surface cover type at the end of the 21st century. Regarding the 10th percentile minimum soil moisture values, the forested area displayed an increasing trend, while the agricultural field and mixed parcel showed a strong decrease. The 30-year monthly means of evapotranspiration shows the maximum values in June and July, while the minimum soil moisture in September. Water stress analysis indicates water stress is expected to occur only in the agricultural field during the 21st century. The comparison of the three surface covers reveals that forest has the greatest soil water storage capacity due to the highest rooting depth. Thus, according to the projections for 21st century, less water stress is predicted to occur at the forested area compared to the other two surface covers which shows shallow rooting depth.

Water requirement of gerberas and their behavior under a water-saving strategy, in northern Bahia

Gerbera crop evapotranspiration was defined, as well as its relationship with meteorological elements and the influence of different irrigation rates on its biometric characteristics, under a shaded mesh environment in Juazeiro-BA. The experiment was performed in randomized 4x2 blocks, with irrigation rates (60; 80; 100; and 120% of water consumption per plant) and gerbera hybrids (‘Essandre’ and DTCS), in five replicates. Gerbera water consumption was determined using total mass variation (vase+substrate+plant) on consecutive days. Total water volume required was 68.19 and 66.9 L plant-1, in DTCS and ‘Essandre’, respectively, in a 240-day cycle after acclimatization, with no significant difference between them. Mean values of the relationship between plant water consumption and reference crop evapotranspiration outside the shaded environment were 0.042 and 0.025L plant-1 mm-1day-1 during the vegetative phase and 0.055 and 0.029 mmL plant-1 mm-1day-1 during the reproductive phase of ‘Essandre’ and DTCS, respectively. The equation (Y=0.1176 *+ 0.0159*x ETo+ 0.0008** x DAA) estimated the water volume required by gerberas. Water stress negatively affected leaf area, number of gerbera leaves, and gerbera leaf temperature, with quadratic behavior.

Physio-Morphological and Biochemical Trait-Based Evaluation of Ethiopian and Chinese Wheat Germplasm for Drought Tolerance at the Seedling Stage

For Ethiopia’s wheat production, drought is a major natural disaster. Exploration of drought-resistant varieties from a bulk of wheat germplasm conserved in the gene bank is of paramount importance for breeding climate change-resilient modern cultivars. The present study was aimed at identifying the best performing drought-resistant genotypes under non-stress and polyethylene glycol simulated (PEG) stress conditions in a growth chamber. Forty diverse Ethiopian bread and durum wheat cultivars along with three Chinese bread wheat cultivars possessing strong drought resistance and susceptibility were evaluated. After acclimation with the natural environment, the seedlings were imposed to severe drought stress (20% PEG6000), and 15 seedling traits including photosynthetic and free proline were investigated. Our findings indicated that drought stress caused a profound decline in plant water consumption (83.0%), shoot fresh weight (64.9%), stomatal conductance (61.6%), root dry weight (55.2%), and other investigated traits except root to shoot length ratio and proline content which showed a significant increase under drought stress. A significant and positive correlation was found between photosynthetic pigments in both growth conditions. Proline exhibited a negative correlation with most of the investigated traits except root to shoot length ratio and all photosynthetic pigments which showed a positive and non-significant association. Our result also showed a wide range of genetic variation (CV) ranging from 3.23% to 47.3%; the highest in shoot dry weight (SDW) (47.3%) followed by proline content (44.63%) and root dry weight (36.03%). Based on multivariate principal component biplot analysis and average sum of ranks (ASR), G12, G16 and G25 were identified as the best drought tolerant and G6, G42, G4, G11, and G9 as bottom five sensitive. The potential of these genotypes offers further investigation at a molecular and cellular level to identify the novel gene associated with the stress response.

Ability of stochastic modelling to forecast crop reference evapotranspiration*

AbstractThe main objective of this study is to evaluate the ability to forecast seasonal and non‐seasonal monthly reference plant water consumption (ET0) with the Box–Jenkins approach (autoregressive integrated moving average), the abbreviation of which is ARIMA (indicated as SARIMA for seasonal series). This target was achieved by using the necessary climate parameters obtained from the Ankara meteorology station to calculate the monthly ET0 data sequences by using the Penman–Monteith relationship. Of the 12 months’ non‐seasonal ET0 data, only 4 months achieved all the conditions expected in simulation after satisfying the stationary condition. The ARIMA (SARIMA) (1,0,1) (3,1,0) model produced the best results among all models providing the necessary conditions for the seasonal series. When comparing the results of ET0 estimation from this model to that of the non‐seasonal series, it was determined that using the seasonal series rather than making an estimate based on the non‐seasonal series provided more successful results, and the model giving the most successful forecast for the study is the SARIMA model above.

Effects of water and salinity stresses on growth, yield, and water use of iceberg lettuce.

Salinity and drought stresses have become widespread in many regions of the world. Although there are several studies, their findings about the response of lettuce to water and salinity stresses are contradictory. This paper therefore aims to evaluate the effects of water deficit and irrigation water salinity on growth, yield, and water consumption of iceberg lettuce. For these purposes, two experiments were carried out under Mediterranean conditions. The water yield response factors (Ky ) determined for the lettuce plant grown under stress conditions caused by water (Ky =1.69) and irrigation water salinity (Ky =2.62) were quite different from each other. The classical salinity tolerance model did not reflect the results accurately because the fresh yield and plant water consumption of lettuce increased sharply with increasing soil salinity up to 2.17 dS m-1 and then decreased slightly after this value. Thus, a new model was created to reflect both the increase and decrease in fresh yield. The actual salt tolerance model for iceberg lettuce plant showed that the optimum salinity is 1.84 dS m-1 with relative yield decreases of 8.26 and 22.7% per unit salinity increase above and below the optimum salinity level, respectively. Lettuce fresh yield at soil salinity below the optimum salinity experienced greater reduction than at soil salinity above the optimum value. The results reveal that the use of low-salinity irrigation water should be preferred to increase fresh yield in iceberg lettuce cultivation. © 2021 Society of Chemical Industry.

Growth and physiological responses of cotton plants to salt stress

AbstractThe objective of this study was to investigate the growth and physiological responses cotton plants to salt stress. At seven leaf stage, cotton plants were subjected to two treatments; 0 mM NaCl as the control and 150 mM NaCl as the salt stress treatment, respectively. The effect of salt stress on leaf gas exchange rates, leaf nitrogen concentration, chlorophyll content, leaf K+ and Na+ concentrations, plant water status, endogenous phytohormone concentrations, dry matter accumulation and partitioning in plant organs was evaluated. The results showed that salt stress significantly decreased plant growth, water consumption, leaf water relations characteristics and leaf gas exchange rates as compared to the control. Under salt, photosynthetic rate was reduced to less extend than did stomatal conductance (gs) and transpiration rate, resulting in greater intrinsic and instantaneous water use efficiencies compared to the control plants. gs decreased linearly with decreasing leaf water potential and leaf hydraulic conductance under salt. Salt‐stressed plants possessed a significant higher concentration of abscisic acid ([ABA]leaf), while a significantly lower concentrations of gibberellic acid ([GA3]leaf) and zeatin riboside ([ZR]leaf) in leaf than those grown under control. Negative linear relationships were found between gs and [ABA]leaf, ratio of [ABA]leaf to [GA3]leaf, ratio of [ABA]leaf to ([GA3]leaf+[ZR]leaf), respectively. Salt stress significantly decreased leaf K+ concentration, the ratio of K+/Na+ in leaf, shoot growth and biomass partitioning into leaf and stem, whereas increased leaf chlorophyll content, leaf nitrogen concentration and biomass partitioning into boll. Although the water use efficiency of plant biomass was unaffected, the water use efficiency of boll biomass was significantly enhanced by salt stress. Collectively, salt‐induced changes in both hydraulic and chemical properties were involved in mediating the leaf gas exchange response to salt stress, and the enhanced leaf nitrogen concentration and biomass partitioning into boll may lead to a sustained yield with less water consumption in cotton plants grown under moderate salinity stress.

Cohabiting Plant-Wearable Sensor In Situ Monitors Water Transport in Plant.

The boom of plant phenotype highlights the need to measure the physiological characteristics of an individual plant. However, continuous real‐time monitoring of a plant's internal physiological status remains challenging using traditional silicon‐based sensor technology, due to the fundamental mismatch between rigid sensors and soft and curved plant surfaces. Here, the first flexible electronic sensing device is reported that can harmlessly cohabitate with the plant and continuously monitor its stem sap flow, a critical plant physiological characteristic for analyzing plant health, water consumption, and nutrient distribution. Due to a special design and the materials chosen, the realized plant‐wearable sensor is thin, soft, lightweight, air/water/light‐permeable, and shows excellent biocompatibility, therefore enabling the sap flow detection in a continuous and non‐destructive manner. The sensor can serve as a noninvasive, high‐throughput, low‐cost toolbox, and holds excellent potentials in phenotyping. Furthermore, the real‐time investigation on stem flow insides watermelon reveals a previously unknown day/night shift pattern of water allocation between fruit and its adjacent branch, which has not been reported before.

Impact of colored water pillows on yield and water productivity of pepper under greenhouse conditions

This study was conducted to investigate the effects of colored water pillows on yield and water productivity of two pepper cultivars under greenhouse conditions in 2018 and 2019. Irrigation treatments were arranged as: drip without mulching, black water pillow, blue water pillow, drip+black mulching and drip+blue mulching. The first year, total plant water consumption amount was about 421 mm for drip and 301 mm for the other treatments and respectively as 439 and 305 mm in the second year. In both years, approximately 38% less water was applied in water pillow irrigation treatments. Significant differences were not observed in yields of water pillow and drip+mulching treatments, but drip irrigation treatments were found to be significantly different from the other treatments in both years. For Captain capia and Yellow Stone chili pepper cultivars, as the average of two years, the highest yields were obtained from water pillow treatments as 39.65 and 32.3 t ha−1, respectively, and the lowest yields were obtained from the drip irrigation treatments as 28.9 and 22.7 t ha−1. There were significant differences in irrigation water productivity (IWP) and water productivity (WP) values of drip irrigation and the other treatments. For Captain capia and Yellow Stone chili pepper, as the average of two years, the highest IWP values were obtained from the water pillow treatments as 121.3 and 96.8 kg ha−1 mm−1, and the lowest IWP value was obtained from the drip irrigation treatments as 65 kg ha−1 mm−1. Similarly, the highest WP values were obtained from the water pillow treatments as 129.5 and 103.25 kg ha−1 mm−1, and the lowest WP value was obtained from the drip treatments as 52.5 kg ha−1 mm−1. A great energy saving was achieved with water pillow method. The amount of energy used in water pillow was about 2% and 5% of the energy used in drip and drip+mulching treatments, respectively. In both years, water pillow and drip+mulching treatments had higher soil temperatures than drip treatment as 1.3 °C. Weeds were not encountered in water pillows and drip+mulching treatments. In conclusion, present findings revealed that water pillows were clearly superior to drip irrigation. Although yield values of water pillows and drip+mulching treatments were not significantly different, no extra energy demand, inherent mulching characteristics and quite low labor costs have made water pillows more advantages over drip+mulching treatments.

Sap flow and plant water sources for typical vegetation in a subtropical humid karst area of southwest China

AbstractPlant water use plays a crucial part in the soil–plant‐atmosphere continuum. However, in karst regions, plants frequently suffer from water shortages due to low soil water storage capacity. Therefore, it is necessary to understand plant water consumption (as determined by sap flow) and seasonal variation of water sources to improve water management in karst catchments. In this study, thermal dissipation probes (TDP), calibrated using empirical equations, were used to measure the sap flow of three typical woody vegetations, including Coriaria nepalensis (sparse‐shrub), Toona sinensis (secondary forest) and Populus adenopoda (shrub‐grass). Oxygen and hydrogen stable isotopes were used to analyze seasonal variation of plant water sources. The results showed that: (1) T. Sinensis (3.89 ± 3.87 L·day−1) had significantly higher daily sap flow than C. nepalensis (0.33 ± 0.37 L·day−1) and P. adenopoda (0.09 ± 0.12 L·day−1); (2) daily sap flow was closely correlated to photosynthetically active radiation (PAR) and vapour pressure deficit (VPD); (3) over the entire study period, plants mainly used water from the surface soil horizons; and (4) a greater proportion of epikarst water was used for C. nepalensis than by T. sinensis and P. adenopoda over the whole growth stage, and more epikarst water was used in early and mid‐growth stages compared to the late stage for the three species. This study contributes to a deeper understanding of the plant water use strategies in karst regions, and is helpful for ecosystem management.

Effect of Skipping Irrigation in Different Phenological Periods on Yield and Some Physiological Parameters of Corn (Zea mays L.)

This study was carried out in Southeastern Anatolia Region in Turkey between 2017 and 2018 to determine the effect of irrigation skipping in different phenological periods on yield and some physiological properties of corn (Zea mays L.) in second crop conditions. The trial is designed as randomized complete block design with three replications. DKC-6664 hybrid corn variety having classified as moderate maturity in the FAO (650-700) maturity classes were used in the study. Four irrigation skipping periods which are full irrigation treatments (S1, control), irrigation skipping in vegetative growth period (S2), irrigation skipping in pollination period (S3), and irrigation skipping in generative development period (S4) were studied in the research. According to the two-year averages; there were statistically significant differences in hybrid corn variety in terms of investigated characteristics. According to results, grain yield (GY), chlorophyll content (CC, spad), water use efficiency (WUE, mm), crop water stress index (CWSI) and plant water consumption (ETa, mm) were ranged from 12761.5 (S2)-14021.3 (S1) kg ha-1, 39.10 (S4)-44.50 (S1) spad, 1.902 (S1)-2.114 (S3) mm, 0.18 (S3)-0.33 (S4) and 6752 (S3)-7712.0 (S1) mm respectively. Because of drier weather conditions in 2017 compared to 2018, while GY, CC, and WUE parameters decreased, CWSI and ETa parameters increased. In the first year of the trial when dry weather conditions prevailed, the corn variety consumed more water and was more stressed. As a result, yield losses were experienced. There were positive and significant correlations between GY and CC and WUE, and negative and significant correlations between CWSI. The results of the study indicated that irrigation should not be skipped during the entire vegetative period for economical and profitable corn production in semi-arid regions.

Energy analysis and water conservation measures by water audit at thermal power stations

Water and energy are sources to fulfill the essential needs of human life for their livelihood. Currently, steam-based power plants utilize water sources such as rivers and lakes. In India, the consumption of water by industries is about 9% of the total, of which power generation sector utilizes 88% of the share. This study examines the quantitative and qualitative analysis of water consumption in power plants to determine the energy losses and water conservation opportunities to reduce, reuse, and recycle water. A typical water audit case study was carried out at specific coal-based Super Thermal Power Station (STPS) in India. The STPS chosen for the study has a commissioned capacity of 3000 MW having three stages of 1 GW each with a total of 6 units having 500 MW each. The present study includes the analysis of overall specific consumption of the plant, ash–water ratio, and cycles of concentration along with the blowdown water quantity along with other water losses. Also, exergy analysis of main water pumps is included, which is ranging from 46 to 67% for Stage-I. Based on the flow and power measurements and overall review of water consumption in the plant water and energy conservation opportunities are suggested which can yield savings up to INR 725.43 lakhs per annum INR (Indian Rupees) with an investment of INR 457 lakhs per annum expecting the payback period to be within a year.

Effect of Soil Water Content and Soil Texture on Phytophthora cinnamomic Infection on Cork and Holm Oak

Phytophthora cinnamomi is an important soil borne plant pathogen, associated to decline of cork and holm oak stands in Iberian Peninsula. This decline results from a complex of biotic and abiotic interactions culminating in root infection. Field observations in cork and holm oak sites suggested an enhancement of soil moisture and texture in decline processes. Greenhouse assays were developed to evaluate the impact of soil moisture and texture on the severity of root infection on both species. Seedlings were potted in P. cinnamomi infested soils with different textures (loamy-sand, clay and silty- loam) combined with different watering regimes (flooding, normal irrigation, and irrigation till wilting and field capacity). The impact of P. cinnamomi infection was assessed through plant biomass, water consumption and root severity. The infection caused either losses of plant biomass (root and shoot) as plants water consumption, in both species, depending on soil moisture and texture. Holm oak plants were more susceptible to P. cinnamomi infection than cork oak, with higher mortality and root degradation. To minimize the risk of infection, watering managing appeared to be an essential condition to optimize plant growth and survival taking also into account the texture and moisture of the soil.

Effects of climate variability and land use/land cover change on the Daihai wetland of central Inner Mongolia over the past decades

The wetland ecosystem and its driving mechanism are significance impact on the ecological environment and the sustainable development of semi-arid regional economy. Agricultural and industrial land use/land cover change (LUCC) is also important for wetland system. The Daihai wetland (DW) in Inner Mongolia has been suffering from severe environmental problems such as water resource shortages and wetland areas decrease. We analyzed spatiotemporal LUCC at the catchment scale of Daihai Lake, which has recently exhibited a dramatic loss of water area, and investigated the potential role of climatic changes and human activities in the wetland loss. From 1976 to 2015, the arable land and construction land increased by 71.72 and 15.81 km2, with ranges of 18.72% and 39.61%, respectively. Meanwhile, the wetland area decreased by 84.47 km2, accounting for 29.07% of the area in 1976. From 1960 to 2015, the area of Daihai Lake decreased by 100.73 km2, diminishing to 37.09% of the area in 1960, and the lake storage accordingly shrank from 12.9 × 108 to approximately 3.9 × 108 m3. The lake level also rapidly declined. From 1962 to 2014, the lake water mineralization, total nitrogen (TN), and total phosphorus (TP) increased by 2410, 7.86, and 0.182 mg L−1, respectively. The pollution sources included not only mineral fertilizers and pesticides, but also livestock, poultry breeding, aquaculture, and rural household waste. The lake area decreased with increasing agricultural development, Daihai power plant (DHPP) water consumption, and catchment climatic dryness. Thus, the urgent implementation of effective restoration and mitigation measures are needed.

Implementation of the Circular Economy Concept in Greenhouse Hydroponics for Ultimate Use of Water and Nutrients

The circular economy in agriculture aims to reduce waste while also making best use of residues by using economically viable processes and procedures to increase their value. In this study a two-level cascade cultivation system was set up under greenhouse conditions. The research was focused on the identification of crop species as secondary crops and the development/iterative optimization of cultivation practices. For this purpose, different crop-combinations with a primary and different secondary crops were investigated using different system-layouts. Measurements were carried out during two cultivation periods. During the 1st Period a combination of cucumber (Cucumis sativus) as primary crop, with rosemary (Rosmarinus officinalis), basil (Ocimum basilicum), and peppermint (Mentha piperita) as secondary crops, was evaluated. In the 2nd Period the drainage of tomato (Solanum lycopersicum) plants was re-used to irrigate spearmint (Mentha spicata), dill (Anethum graveolens), celery (Apium graveolens) and parsley (Petroselinum crispum) plants. In both periods, different fertigation management strategies based on the drainage solution of the primary crop were employed. The use of the cascade hydroponic system improved both crop water and nutrient use efficiency. Notably, the NO3 disposal was about 40% less as compared to a monoculture. Average fresh water consumption of secondary crop plants irrigated with diluted drainage solution was reduced by 30% in comparison to plants irrigated with fresh water.

Proposal and techno-economic analysis of a novel system for waste heat recovery and water saving in coal-fired power plants: A case study

A novel system, which systematically recover waste heat and reduce water consumption in coal-fired power plants, is proposed in this paper. Critical components of the system are two fluorine plastic heat exchangers (FHEs) located downstream and upstream of WFGD scrubber, and condensate and feed water extracted from the regenerative heater (RH) act as coolants, respectively. All recovered heat is utilized directly with no heat pump required. A thermodynamic model, where the steam/water cycle is coupled with the exhaust flue gas flow, is built to assess the performance of the system, and the economic analysis is involved to further explore the feasibility. The simulation is conducted based on parameters of a 1000 MW coal-fired power unit in operation, while coal and water saving rates, payback period, and net present value (NPV) are used as criteria in the assessment. The results show that the system can significantly reduce coal and water consumption of the reference power unit. The temperature of condensate and feed water extraction determines the techno-economic performance of the low- and high-temperature FHEs (LFHE and HFHE), respectively. Lower condensate temperature and higher feed water extraction temperature are more beneficial. Compared with the case of only LFHE, integrating HFHE into the system will increase the overall coal and water saving rates obviously, although the performance of LFHE is weakened. All layouts of the system presented in this paper are techno-economically feasible, and the layout in Case 4 where HFHE is installed in parallel with RH6 is the optimal one. Coal and water saving rates, and NPV of the optimal layout are up to 4.11 g/kWh, 95 t/h, and 102,739,000 RMB, respectively, while the payback period is less than 4 y. Application of this system is beneficial to mitigating the environmental problems caused by coal-fired power generation.

Evapotranspiration Partitioning at Field Scales Using TSEB and Multi-Satellite Data Fusion in The Middle Reaches of Heihe River Basin, Northwest China

Daily evapotranspiration (ET) and its components of evaporation (E) and transpiration (T) at field scale are often required for improving agricultural water management and maintaining ecosystem health, especially in semiarid and arid regions. In this study, multi-year daily ET, E, and T at a spatial resolution of 100 m in the middle reaches of Heihe River Basin were computed based on an ET partitioning method developed by combing remote sensing-based ET model and multi-satellite data fusion methodology. Evaluations using flux tower measurements over irrigated cropland and natural desert sites indicate that this method can provide reliable estimates of surface flux partitioning and daily ET. Modeled daily ET yielded root mean square error (RMSE) values of 0.85 mm for cropland site and 0.84 mm for desert site, respectively. The E and T partitioning capabilities of this proposed method was further assessed by using ratios E/ET and T/ET derived from isotopic technology at the irrigated cropland site. Results show that apart from early in the growing season when the actual E was reduced by plastic film mulching, the modeled E/ET and T/ET agree well with observations in terms of both magnitude and temporal dynamics. The multi-year seasonal patterns of modeled ET, E, and T at field scale from this ET partitioning method shows reasonable seasonal variation and spatial variability, which can be used for monitoring plant water consumption in both agricultural and natural ecosystems.

Monitoring water consumption of the slate manufacturing plant

This article provides normative calculations of water consumption and water supply for slate production, water consumption for technical processes and for household and drinking needs. As well as, wasted water analysis, monitoring and efficiency of the treatment plant.

Особливості водоспоживання рослин люпину білого в умовах Правобережного Лісостепу

Особливості водоспоживання рослин люпину білого в умовах Правобережного Лісостепу

Método de Penman-Monteith e Hargreaves-Samani para obtenção da ETo em ano chuvoso e seco

O planejamento e aproveitamento da água na produção agrícola, bem como o desenvolvimento de metodologias que permitam estimar o correto volume de água são fundamentais para o estabelecimento de planos eficientes de irrigação, evitando o desperdício. A evapotranspiração está diretamente relacionada ao consumo de água das plantas, desta forma, foram desenvolvidos diversos métodos para a determinação da evapotranspiração utilizando para isso, as variáveis meteorológicas. Dessa forma objetivou-se avaliar umas das metodologias mais utilizadas, que é o conhecida como método de Hargreaves-Samani para estimar a evapotranspiração de referência (ETo) em condições de baixa e elevada pluviosidade, utilizando como referência o método de Penman-Monteith-FAO56. Foram empregados dados de uma estação meteorológica automática pertencente à Universidade Federal Rural do Semi-Árido, em Mossoró (RN), os dados mencionados são referentes ao período de janeiro de 2011 a dezembro de 2012. A ETo foi estimada sendo considerada de uso prático, o modelo de Hargreaves-Samani que utiliza elementos meteorológicos de fácil obtenção como a temperatura, umidade relativa do are velocidade do vento, permitindo a estimativa da ETo é considerado de uso prático. Verificou-se que, as estimativas a partir do método de Hargreaves-Samani superestimaram os valores de ETo quando comparado com o método padrão em condições de elevada umidade para o ano de 2011, além de apresentar significância quanto a variável velocidade do vento, desta forma podendo ser fortemente influenciada por ela. Diante disso verifica-se a necessidade de calibração ou parametrização dos coeficientes da equação de Hargreaves-Samani como alternativa para uma melhor estimativa, principalmente para cidades com influência litorânea.