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Modelling reference evapotranspiration using gene expression programming and artificial neural network at Pantnagar,India

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Information Processing in Agriculture 2023年第4期10卷 547-563页

作者： Pangam Heramb Pramod Kumar Singh K.V.Ramana Rao A.Subeesh Division of irrigation and Drainage Engineering ICAR-Central Institute of Agricultural EngineeringBhopal 462038India department of irrigation and Drainage Engineering G.B.Pant University of Agriculture and TechnologyPantnagar 263145India Division of agricultural Mechanization ICAR-Central Institute of Agricultural EngineeringBhopal 462038India

Evapotranspiration is an essential component of the hydrological cycle that is of particular interest for water resource *** quantification is helpful in irrigation scheduling,water balance studies,water allocation,*** of reference evapotranspiration(ET0)using both gene expression programming(GEP)and artificial neural network(ANN)techniques was done using the daily meteorological data of the Pantnagar region,India,from 2010 to 2019.A total of 15 combinations of inputs were used in developing the ET0 *** model with the least number of inputs consisted of maximum and minimum air temperatures,whereas the model with the highest number of inputs consisted of maximum air temperature,minimum air temperature,mean relative humidity,number of sunshine hours,wind speed at 2mheight and extra-terrestrial radiation as inputs and with ET0 as the output for all the *** the GEP models were developed for a single functional set and pre-defined genetic operator values,while the best structure in each ANN model was found based on the performance during the testing *** was found that ANN models were superior to GEP models for the estimation *** was evident from the reduction in RMSE values ranging from 2%to 56%during training and testing phases in all the ANN models compared with GEP *** ANN models showed an increase of about 0.96%to 9.72%of R2 value compared to the respective GEP *** comparative study of these models with multiple linear regression(MLR)depicted that the ANN and GEP models were superior to MLR models.

关键词： Artificial Neural Networks Evolutionary algorithms Gene Expression Programming Machine Learning Regression Analysis Reference evapotranspiration models

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The Potential of Hydro-Climate Forecast Strategies in Sustaining agricultural Productivity amongst Rainfed Farmers in West Africa: A Review

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American Journal of Climate Change 2022年第4期11卷 265-283页

作者： Richard Kwame Dogbey Gordana Kranjac-Berisavljevic Bizoola Zinzoola Gandaa department of agricultural mechanisation and irrigation technology Faculty of Agriculture Food and Consumer Sciences University for Development Studies Tamale Ghana

Several studies have reported a significant yearly decrease in forest cover globally, using satellite images. This is especially true in West Africa, where rapid urbanisation acerbates the problem, and both of these changes lead to alterations in rainfall regime and other changes in climatic parameters. Several studies reveal that adaptation which reduces vulnerability to adverse climatic variation effects is the key to developing resilience against climate change. In this region, over 90% of farmers are engaged in small-scale rainfed crop cultivation and rely on their own weather perception, instincts and what they observe from the surrounding biota (flora and fauna) to forecast the weather and plan their agricultural activities. The pressing nature of the problem of climate variability in Africa had provoked a lot of research into developing and testing several adaptation strategies to control the situation. Various strategies to improve and localize global, regional and national climate services (Local Forecast, Scientific Forecast and Integrated Forecast) needed by the farmers are being developed to build resilience against climate change. This review illustrates the situation in Ghana and identifies various forecast strategies developed to mitigate the adverse effects of climate variability on agricultural productivity. These mitigation methods include the development of climate services to provide users with forecast information in order to make climate-smart decisions to minimize the risk.

关键词： Climate Variability Adaptation Strategies Forecast Strategies Resilience Rainfed Agriculture

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Climate change impact assessment on three major crops in the north-central region of Bangladesh using DSSAT

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International Journal of agricultural and Biological Engineering 2018年第4期11卷 135-143页

作者： Atikur Rahman Mohammad Abdul Mojid Selina Banu department of irrigation and Water Management Bangladesh Agricultural UniversityMymensingh-2202Bangladesh department of agricultural and Industrial Engineering Hajee Mohammad Danesh Science and Technology UniversityDinajpur-5200Bangladesh

The potential consequences of climate change emanated from global warming are very alarming;the greatest concern is the potentially disastrous consequences on crop agriculture and food security in many parts of the *** is a country highly susceptible to climate change,but information in this regard is still *** study investigated the effects of climate change on three major crops-wheat,potato and rice-in the north-central region of *** climate change scenarios,A2 and B2,of the Intergovernmental Panel on Climate Change(IPCC)were generated by employing MAGICC/SCENGEN model together with the observed climate data of the *** growth and yield of the crops were simulated using DSSAT CERES-Wheat,SUBSTOR-Potato and CERES-Rice models under the present and projected future changing climatic *** a predicted 5.32℃ increase in temperature in the year 2100,the yield of wheat,rice and potato would decrease by 47.6%,67.8%and 38.6%,*** increased temperature would accelerate physiological maturity of the crops as reflected by their reduced length of growing season(LGS)by 1.20%to 18.5%.The reduced LGS would reduce seasonal evapotranspiration(ET)of the crops by shortening time-span for ET *** to dominant yield reduction over ET reduction,the water use efficiency(WUE)for grain/tuber and biomass yields would decrease with the changing *** reduced crop yields are an indicative of a potential future risk of food security in *** results of this study can therefore guide to adopt coping mechanisms in the light of climate change to ensure future food security of the country.

关键词： climate change DSSAT MAGICC/SCENGEN model CERES model SUBSTOR model growing season length crop-water use

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Performance evaluation of a diesel engine by using producer gas from some under-utilized biomass on dual-fuel mode of diesel cum producer gas

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Journal of Central South University 2012年第6期19卷 1583-1589页

作者： D.K.Das S.P.Dash M.K.Ghosal department of Farm Machinery and Power College of Agricultural Engineering and TechnologyOrissa University of Agriculture and TechnologyBhubnaneswar-751003OrissaIndia department of Water Resources Orissa Lift irrigation CorporationGovernment of OrissaIndia

Producer gas through gasification of biomass can be used as an alternate fuel in rural areas due to high potential of biomass resources in *** were conducted to study the performance of a diesel engine(four stroke,single cylinder,5.25 kW) with respect to its thermal efficiency,specific fuel consumption and diesel substitution by use of diesel alone and producer gas-cum-diesel(dual fuel mode).Three types of biomass,*** chips,pigeon pea stalks and corn cobs were used for generation of producer gas.A producer gas system consisting of a downdraft gasifier,a cooling cum cleaning unit,a filtering unit and a gas air mixing device was designed,fabricated and used to power a 5.25 kW diesel engine on dual fuel *** of the engine was reported by keeping biomass moisture contents as 8%,12%,16%,and 21%,engine speed as 1 600 r/min and with variable engine *** average value of thermal efficiency on dual fuel mode was found slightly lower than that of diesel *** specific diesel consumption was found to be 60%-64% less in dual fuel mode than that in diesel mode for the same amount of energy *** average diesel substitution of 74% was observed with wood chips followed by corn cobs(78%) and pigeon pea stalks(82%).Based on the performance studied,the producer gas may be used as a substitute or as supplementary fuel for diesel conservation,particularly for stationary engines in agricultural operations in the farm.

关键词： biomass gasification producer gas downdraft gasifier diesel engine

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Field curing methods and storage duration affect the quality of hay from six rangeland grass species in Kenya

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Ecological Processes 2016年第1期5卷 32-37页

作者： O.K.Koech R.N.Kinuthia G.N.Karuku S.M.Mureithi R.Wanjogu department of Land Resource Management and agricultural technology Range Management SectionUniversity of NairobiP.O.Box 209053-00625NairobiKenya National irrigation Board Mwea Irrigation Agricultural Development(MIAD)CentreP.O.Box 21010303 WanguruKenya

Introduction:Rangelands are important source of pasture for livestock in Kenya since time immemorial to pastoral ***,seasonality on forage availability has been a big challenge in meeting animals’feed *** demands harvest and storage of pastures for use during dry *** making has been done to bridge this forage deficit ***,hay quality in the rangelands is affected by curing methods,phonological stage at harvest,and the storage *** therefore evaluated the effect of field curing and storage duration on the quality(Crude Protein(CP))of hay from six rangeland grasses in ***:The grasses evaluated are Chloris roxburghiana,Eragrostis superba,Enteropogon macrostachyus,Cenchrus ciliaris,Chloris gayana,and Sorghum *** grasses are the common species in the rangelands of Kenya and have been promoted in the past for hay making and reseeding *** grasses were harvested at the mature flowering stage(12 weeks phenological stage),which is a period that provides high biomass without much effect on quality as practiced in the study *** grasses were then cured in the field for 1,2,and 3 days before baling and stored indoors for 12,24,and 36 *** were taken for CP content determination at the three periods following Macro-Kjeldahl ***:There was significant decline(p≤0.05)in crude protein content in all the grass species with storage *** period did not affect the CP content for all the species at a given storage period;however,3 days curing changed the hay color from green to brownish which reduces palatability and consequently reduced feed *** period of over 12 weeks adversely lowered CP to less than 6% for all the species which is the required minimum level for animal under production and *** had significantly higher decline in CP after 24 weeks storage compared to the other ***:Therefore,hay from the six grass spec

关键词： Grass quality Range grasses Semi-arid rangelands Grass storage Grass curing Kenya

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Tree-Temperature Monitoring for Frost Protection of Orchards in Semi-Arid Regions Using Sprinkler irrigation

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agricultural Sciences in China 2009年第1期8卷 98-107页

作者： Ali Asghar Ghaemi Mohammad Rafie Rafiee Ali Reza Sepaskhah irrigation department College of AgricultureShiraz University

Automated over-tree sprinkler irrigation systems were developed and tested in two orchards located in two separate locations in southern Iran （a 0.17 ha peach orchard and a 0.24 ha orange orchard） to protect peach blossoms and orange trees leaves and fruits from low temperature damage. The experiment used a system that monitored the trees and air temperatures using two thermistors. The water application rate by the irrigation system was determined by an energy balance as implemented by the software FROSTPRO, In the peach orchard, the system was tested during three frost events during the spring of 2003 and three other events during the spring of 2004. The system successfully kept peach flowers above the critical temperature, i.e., -4.0℃ in spring 2004 （control block -4.12℃, and sprinkled block ＋0.5℃） during all events. Similar results were obtained in the orange orchard during three frost events in the winter of 2004, during which the tree temperatures were at least 2.5℃ above the critical temperature. Results from field tests show that the system can effectively protect the peach blossoms from damage. Determination done after the frost events showed a 12% blossom kill in the sprinkled blocks while in the unsprinkled control block a 41.5% blossom kill. Calculations indicated that when using variable application rates, the amount of water used can be reduced by 54.3%. Spatial distribution of minimum temperatures during the three frosts was also studied in Jahrom, Iran. Results showed a significant temperature control in the experimental block, especially in the central part of the orchard, but the block margins （about 3.6% of the total area） were at the risk of low temperature due to the wind drift effects.

关键词： automated sprinkler irrigation FROSTPORO frost protection peach orchard orange orchard

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Estimation of Infiltration Models’ Parameters Using Regression Analysis in irrigation Fields of Northern Ghana

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Open Journal of Soil Science 2021年第3期11卷 164-176页

作者： Abdallah Salifu Felix. K. Abagale Gordana Kranjac-Berisavljevic department of agricultural mechanisation and irrigation technology Faculty of Agriculture Food and Consumer Sciences University for Development Studies Tamale Ghana West African Centre for Water Irrigation and Sustainable Agriculture University for Development Studies Tamale Ghana

The quantification of soil infiltration is necessary for the estimation of water accessibility in soils for plant growth and development. Field infiltration tests runs were conducted on agricultural soils in three irrigation sites of Northern Ghana. The field data were fitted into Green and Ampt, Kostiakov, Philip, Holtan, Soil Conservation Service and Horton infiltration models for the determination of the unknown model parameters. Regression analysis at 95% confidence level using GraphPad Prism 8. Laboratory and field data on infiltration were used for the model fitting and the unknown parameters were determined using the calibrated models. The k and n parameters of Kostiakov model at Bontanga study site were found to be k = 28.0027 and n = 0.5902, k = 17.0294 and n = 0.4504 for Golinga and k = 23.0356 and n = 0.6339 for Libga. For all the models, the coefficient of determination ranged from 0.7612 to 0.9876 indicating strong relationships. Only Holtan model gave different values at all the three study sites. The parameter GIa and ic of the Holtan model drawn from hydrologic soil group were the same at all the study sites because of the same vegetative cover and surface conditions. The study observed the values of the parameters to have influenced the models’ performance.

关键词： Parameter Infiltration Model Regression Sorptivity Transmissivity

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Optimization of equitable irrigation water delivery for a large-scale rice irrigation scheme

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International Journal of agricultural and Biological Engineering 2018年第5期11卷 160-166页

作者： Md Rowshon Kamal Muhammad Iqbal Md Abdul Mojid Mohd Amin Mohd Soom Lai Sai Hin department of Biological and agricultural Engineering Faculty of EngineeringUniversiti Putra Malaysia(UPM)UPM Serdang 43400Selangor DEMalaysia department of agricultural Engineering and technology Faculty of Agricultural SciencesGhazi UniversityDera Ghazi KhanPakistan department of irrigation and Water Management Faculty of Agricultural Engineering and TechnologyBangladesh Agricultural UniversityMymensingh 2202Bangladesh Faculty of Sustainable Agriculture Universiti Malaysia Sabah(UMS)Jalan UMSKota Kinabalu 88400SabahMalaysia department of Civil Engineering Faculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia

Equitable water allocation is essential in an irrigation scheme for obtaining potential crop yields from the entire scheme,especially when water supply is *** optimization model achieved this goal by coupling an optimal water allocation model with available water supply and irrigation water demand for a river-fed rice irrigation system in *** model consists of a paddy field water balance module and an optimization *** outputs from the module are daily irrigation demand and surface runoff,if there is *** optimization module consists of an objective function,which minimizes water shortage across the scheme area while maintaining equity in water *** model performs optimization subject to several system constraints,and the decision variable of the model is daily releases or supply to the tertiary *** of this model remained unaffected under different water supply conditions,and the optimization model reliably examined the effects of alternate water allocation and management rules with field *** improves efficiency and equity in water allocation with respect to crop growth stages and water shortages rather than simply cutting irrigation supply on a proportional basis to overcome water shortages.

关键词： irrigation optimization simulation equitable deliveries rice

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Soil Salinity Changes in the Jordan Valley Potentially Threaten Sustainable Irrigated Agriculture

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Pedosphere 2013年第3期23卷 376-384页

作者： T.G.AMMARI R.TAHHAN S.ABUBAKE Y.AL-ZU'BI A.TAHBOUB R.TA'ANY S.ABU-ROMMAN N.AL-MANASEER M.H.STIETIYA department of Water Resources and Environmental Management Faculty of Agricultural Technology Al-Balqa' Applied University department of Natural Resources and Environment Faculty of Agriculture Jordan University of Science and Technology department of Plant Production and Protection Faculty of Agricultural Technology Al-Balqa' Applied University department of Biotechnology Faculty of Agricultural Technology Al-Balqa' Applied University department of Land Water and Environment Faculty of Agriculture University of Jordan

The integrated effect of irrigation and agricultural practices on soil salinity in the Jordan Valley （JV）, where over 60% of Jordan＇s agricultural produce is grown, was investigated in this study during 2009-2010. Due to the differences in agricultural operations, cropping patterns, irrigation management, and weather conditions, 206 top- and sub-soil samples were taken every 1 to 3 km from representative farms along a north-south （N-S） transect with 1 to 2 km lateral extents. Soil electrical conductivity of saturated extract （ECse）, Ca, Mg, K, Na, CI, and Na adsorption ratio （SAR） were determined in saturated paste extracts. Results indicated that about 63% of soils in the JV are indeed saline, out of which almost 46% are moderately to strongly saline. Along the N-S transect of the JV, ECse increased from 4.5 to 14.1 dS m-1 in top-soil samples. Similar increase was observed for the sub-soil samples. The major chemical components of soil salinity; i.e., Ca, Mg, and C1, also showed a similar increase along the N-S transect of the valley. Moreover, compared to previous field sampling, results showed that changes in soil salinity in the JV were dramatic. In addition, it was found that C1 imposed an existing and potential threat to sensitive crops in 60% of the soils in the JV, where C1 concentrations were greater than 710 mg L-1. Under the prevalent arid Mediterranean conditions, improving the management of .irrigation water, crops, and nutrient inputs and increasing water and fertilizer use efficiencies should be indispensable to conserve and sustain the already fragile agricultural soils in the JV.

关键词： agricultural practices chloride electrical conductivity irrigation water quality soil salinization

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Combining PlanetScope and Sentinel-2 images with environmental data for improved wheat yield estimation

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International Journal of Digital Earth 2023年第1期16卷 847-867页

作者： Nizom Farmonov Khilola Amankulova József Szatmári Jamol Urinov Zafar Narmanov Jakhongir Nosirov LászlóMucsi department of Geoinformatics Physical and Environmental GeographyUniversity of SzegedSzegedHungary Tashkent Institute of irrigation and agricultural Mechanization Engineers National Research UniversityTashkentUzbekistan department of Land resources Cadastre and GeoinformaticsKarshi Institute of Irrigation and Agrotechnology“TIIAME”National Research UniversityKarshiUzbekistan Soil Science department of the Kashkadarya Region regional division of the Institute of Soil Science and Agrochemical Research KarshiUzbekistan

Satellite images are widely used for crop yield estimation,but their coarse spatial resolution means that they often fail to provide detailed information at thefield ***,a new generation of high-resolution satellites and CubeSat platforms has been *** this study,satellite data sources including PlanetScope and Sentinel-2 were combined with topographic and climatic variables,and the improvement in wheat yield estimation was *** yield data from a combine harvester were used to train and validate a yield estimation model based on random forest *** vegetation indices(NDVI,GNDVI,MSAVI2,MTVI2,MTCI,reNDVI,SAVI,EVI and WDVI)and spectral bands were *** the model training,the Sentinel-2 data realized a slightly higher estimation accuracy than the PlanetScope ***,combining environmental data with the PlanetScope data realized the highest estimation *** the validated models,adding the topographic and climatic datasets to the satellite data sources improved the estimation accuracy,and the results were slightly better with the Sentinel-2 data than with the PlanetScope *** data of the milk and dough stages provided the highest estimation accuracy of the wheat yield at 210–225 days after sowing.

关键词： Remote sensing BBCH-scale MSAVI2 PlanetScope random forest

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