Mathematical model of agricultural crop yield

Theoretical basis for presenting research results in agricultural science is mathematical statistics and probability theory using empirical forms of generalization of experimental data. To improve the methods of planning field experiment and processing its data using digital technologies, we proposed to use mathematical modeling based on physical principle of balance of cause-and-effect interactions in a closed physical system as a priority option. When analyzing impact of environmental factors on crop yields, the initial provisions, the mathematical modeling of the crop yield is based, on are not associated with characteristics of crops and natural conditions, therefore, the model options are universal in application and are valid for any agricultural crop, regardless of the region of cultivation. To ensure statistically correct digital information, based on the established forms of mathematical model, the field experiment layout aimed at establishing the dependence of the crop yield on yield-forming factors should include at least 4 options for nutritional levels (NPK) with a research duration of at least 4 years. To check the accuracy of the developed crop yield model, the data of independent field experiments of Professor N.N. Semenenko with barley and winter triticale has been used. It has been determined that, in Belarus, yield-forming factors, as a result of their impact on the grain yield, are arranged in the following decreasing sequence: total dose of applied NPK º the amount of precipitation during the active phases of growing season → air temperature for the same period. Calculations have shown that decrease in the number of yield-forming factors taken into account in the mathematical model from three (food, moisture and heat) to two (food and moisture) reduces the accuracy of calculating the grain crop yield insignificantly.

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ECONOMIC AND PHYSICAL MODELING OF LAND USE IN GCAM 3.0 AND AN APPLICATION TO AGRICULTURAL PRODUCTIVITY, LAND, AND TERRESTRIAL CARBON

Climate Change Economics ◽

10.1142/s2010007814500031 ◽

2014 ◽

Vol 05 (02) ◽

pp. 1450003 ◽

Cited By ~ 50

Author(s):

MARSHALL WISE ◽

KATE CALVIN ◽

PAGE KYLE ◽

PATRICK LUCKOW ◽

JAE EDMONDS

Keyword(s):

Land Use ◽

Crop Yield ◽

Carbon Emissions ◽

Crop Yields ◽

Assessment Model ◽

Agricultural Crop ◽

Terrestrial Carbon ◽

Global Change Assessment Model ◽

The Impact

The release of the Global Change Assessment Model (GCAM) version 3.0 represents a major revision in the treatment of agriculture and land-use activities in a model of long-term, global human and physical Earth systems. GCAM 3.0 incorporates greater spatial and temporal resolution compared to GCAM 2.0. In this paper, we document the methods embodied in the new release, describe the motivation for the changes, compare GCAM 3.0 methods to those of other long-term, global agriculture-economy models and apply GCAM 3.0 to explore the impact of changes in agricultural crop yields on global land use and terrestrial carbon. In the absence of continued crop yield improvements throughout the century, not only are cumulative carbon emissions a major source of CO 2 emissions to the atmosphere, but bioenergy production remains trivial — land is needed for food. In contrast, the high crop yield improvement scenario cuts terrestrial carbon emissions dramatically and facilitates both food and energy production.

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Agricultural Beneficial Management Practices: A Synthesis of Co-benefits, Tradeoffs, and Co-costs between Crop Yield and Non-provisioning Ecosystem Services

10.32942/osf.io/ycwek ◽

2020 ◽

Author(s):

Andrew Nicholas Kadykalo ◽

Kris Johnson ◽

Scott McFatridge ◽

C. Scott Findlay

Keyword(s):

Ecosystem Services ◽

Crop Yield ◽

Cover Crops ◽

Management Practices ◽

Crop Yields ◽

Crop Rotations ◽

Agricultural Crop ◽

Beneficial Management Practices ◽

Provisioning Ecosystem Services ◽

The Impact

Although agricultural “best (or beneficial) management practices” (BMPs) first emerged to mitigate agro-environmental resource challenges, they may also enhance ‘non-provisioning’ ecosystem services. The enthusiasm for adopting BMPs partially depends on evidence that doing so will lead to agro-environmental benefits while not substantially reducing crop productivity or farmer income. We survey and synthesize evidence in the existing literature to document the joint effects on agricultural crop yield and 12 ecosystem service (ES) associated with implementation of 5 agricultural BMPs (crop rotations, cover crops, nutrient management, perennial vegetated buffers, reduced or no tillage). We also analyze the prevalence of co-benefits (‘win-win’), tradeoffs, and co-costs (‘lose-lose’) outcomes. On the basis of a set of contextual variables we then develop empirical models that predict the likelihood of co-benefits relative to tradeoffs, and co-costs. We found thirty-six studies investigating 141 combinations of crop yields and non-provisioning ES outcomes (YESs) in the relevant literatures covering the period 1983-2016. The scope of the review is global, but included studies are geographically concentrated in the U.S. Corn Belt (Midwestern United States). In the literature sample, reporting of co-benefits (26%) was much more prevalent than reporting of co-costs (4%) between yields and ES. Tradeoffs most often resulted in a reduction in crop yields and an increase in ES (28%); this was marginally greater than studies reporting a neutral influence on crop yields and an increase in ES (26%). Other Y/ES combinations were uncommon. Mixed-effects models indicated reduced tillage and crop rotations had generally positive associations with YESs. Temporal scale was an informative predictor suggesting studies with longer time scales resulted in greater positive outcomes on YESs, on average. Our results are a step towards identifying those contexts where co-benefits or partial improvement outcomes of BMPs are more likely to be realized, as well as the impact of particular practices on specific ES.

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Water in the circular economy: using recycled water for sub-irrigation purposes

10.5194/egusphere-egu2020-8052 ◽

2020 ◽

Author(s):

Ruud P. Bartholomeus ◽

Marjolein H.J. van Huijgevoort ◽

Arnaut van Loon

Keyword(s):

Water Management ◽

Soil Moisture ◽

Pilot Study ◽

Water Supply ◽

Field Experiments ◽

Crop Yields ◽

Treated Wastewater ◽

Agricultural Crop ◽

Agricultural Water ◽

Groundwater Availability

<p><span>Agricultural crop yields depend largely on soil moisture conditions in the root zone. Climate change leads to more prolonged drought periods that alternate with more intensive rainfall events. With unaltered water management practices, reduced crop yield due to drought stress will increase. Therefore, both farmers and water management authorities search for opportunities to manage risks of decreasing crop yields. Available groundwater sources for irrigation purposes are increasingly under pressure due to the regional coexistence of land use functions that are critical to groundwater levels or compete for available water. At the same time, treated wastewater from industries and domestic wastewater treatment plants are quickly discharged via surface waters towards sea. Exploitation of these freshwater sources may be an effective strategy to balance regional water supply and agricultural water demand. We present results of a pilot study in a drought sensitive region in the Netherlands, concerning agricultural water supply through reuse of industrial treated wastewater. The Bavaria Beer Brewery discharges treated wastewater to the surface water. Nevertheless, neighboring farmers invest in sprinkler irrigation to maintain their crop production during drought periods. Doing so, increasing pressure is put on the regional groundwater availability. Within a pilot study, a sub-irrigation system has been installed, by using subsurface drains, interconnected through a collector drain, and connected to an inlet control pit for the treated wastewater to enter the drainage system. Sub-irrigation is a subsurface irrigation method that can be more efficient than classical, aboveground irrigation methods using sprinkler installations. Additionally, sub-irrigated water that is not used for plant transpiration recharges the groundwater. We combine both process-based modeling of the soil-plant-atmosphere system and field experiments to i) investigate the amount of water that needs to be and that can be sub-irrigated, and ii) quantify the effect on soil moisture availability and herewith reduced needs for aboveground irrigation from groundwater.</span></p>

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EFFECT OF MOLYBDENUM APPLICATIONS ON PLANT MOLYBDENUM CONCENTRATION AND CROP YIELDS ON SPHAGNUM PEAT SOILS

Canadian Journal of Soil Science ◽

10.4141/cjss90-073 ◽

1990 ◽

Vol 70 (4) ◽

pp. 717-721 ◽

Cited By ~ 1

Author(s):

UMESH C. GUPTA ◽

P. V. LEBLANC ◽

E. W. CHIPMAN

Keyword(s):

Key Words ◽

Crop Yield ◽

Plant Tissue ◽

Field Experiments ◽

Crop Yields ◽

Red Clover ◽

Peat Soils ◽

Sphagnum Peat ◽

Molybdenum Concentration ◽

Clover Plant

Studies were conducted on peat soils to determine the effect of Mo application on crop yields and plant tissue Mo concentrations. In a greenhouse experiment Mo applications resulted in highest crop yield increases for cauliflower with lesser increases for onions and red clover. Plant tissue Mo levels of less than 0.06, 0.04, and 0.03 mg kg−1 in onions, cauliflower, and red clover, respectively were in the deficiency range. Sufficiency levels for Mo were 0.1 mg kg−1 for onions, 0.07 mg kg−1 for cauliflower, and 0.27 mg kg−1 for red clover. No response to Mo was found on carrots even at plant tissue Mo concentrations as low as 0.04 and 0.15 mg kg−1 under greenhouse and field experiments, respectively. In the field study liming and Mo both increased carrot leaf Mo concentrations but only liming increased carrot yields. Key words: Molybdenum concentration, vegetables, red clover, sphagnum peat, liming

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A Flexible Parametric Family for the Modeling and Simulation of Yield Distributions

Journal of Agricultural and Applied Economics ◽

10.1017/s1074070800003473 ◽

2010 ◽

Vol 42 (2) ◽

pp. 303-319 ◽

Cited By ~ 7

Author(s):

Octavio A. Ramirez ◽

Tanya U. McDonald ◽

Carlos E. Carpio

Keyword(s):

Modeling And Simulation ◽

Crop Yield ◽

Crop Yields ◽

Parametric Models ◽

Parametric Family ◽

Yield Model ◽

Central Moments ◽

Mean Variance

The distributions currently used to model and simulate crop yields are unable to accommodate a substantial subset of the theoretically feasible mean-variance-skewness-kurtosis (MVSK) hyperspace. Because these first four central moments are key determinants of shape, the available distributions might not be capable of adequately modeling all yield distributions that could be encountered in practice. This study introduces a system of distributions that can span the entire MVSK space and assesses its potential to serve as a more comprehensive parametric crop yield model, improving the breadth of distributional choices available to researchers and the likelihood of formulating proper parametric models.

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Modeling Regional Crop Yield and Irrigation Demand Using SMAP Type of Soil Moisture Data

Journal of Hydrometeorology ◽

10.1175/jhm-d-14-0034.1 ◽

2015 ◽

Vol 16 (2) ◽

pp. 904-916 ◽

Cited By ~ 10

Author(s):

Husayn El Sharif ◽

Jingfeng Wang ◽

Aris P. Georgakakos

Keyword(s):

Soil Moisture ◽

Crop Yield ◽

Crop Yields ◽

Cropping System ◽

Crop Model ◽

Agricultural Crop ◽

Irrigation Amount ◽

Soil Moisture Data ◽

Efficient Data ◽

Type Data

Abstract Agricultural models, such as the Decision Support System for Agrotechnology Transfer cropping system model (DSSAT-CSM), have been developed for predicting crop yield at field and regional scales and to provide useful information for water resources management. A potentially valuable input to agricultural models is soil moisture. Presently, no observations of soil moisture exist covering the entire United States at adequate time (daily) and space (~10 km or less) resolutions desired for crop yield assessments. Data products from NASA’s upcoming Soil Moisture Active Passive (SMAP) mission will fill the gap. The objective of this study is to demonstrate the usefulness of the SMAP soil moisture data in modeling and forecasting crop yields and irrigation amount. A simple, efficient data assimilation algorithm is presented in which the agricultural crop model DSSAT-CSM is constrained to produce modeled crop yield and irrigation amounts that are consistent with SMAP-type data. Numerical experiments demonstrate that incorporating the SMAP data into the agricultural model provides an added benefit of reducing the uncertainty of modeled crop yields when the weather input data to the crop model are subject to large uncertainty.

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A Spatially Explicit Crop Yield Model to Simulate Agricultural Productivity for Past Societies under Changing Environmental Conditions

Water ◽

10.3390/w13152023 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2023

Author(s):

Maarten Van Loo ◽

Gert Verstraeten

Keyword(s):

Crop Yield ◽

Crop Yields ◽

Time Window ◽

Computational Time ◽

Spatially Explicit ◽

Yield Model ◽

Soil Thickness ◽

Aquacrop Model ◽

The Impact ◽

Strong Control

Most contemporary crop yield models focus on a small time window, operate on a plot location, or do not include the effects of the changing environment, which makes it difficult to use these models to assess the agricultural sustainability for past societies. In this study, adaptions were made to the agronomic AquaCrop model. This adapted model was ran to cover the last 4000 years to simulate the impact of climate and land cover changes, as well as soil dynamics, on the productivity of winter wheat crops for a Mediterranean mountain environment in SW Turkey. AquaCrop has been made spatially explicit, which allows hydrological interactions between different landscape positions, whilst computational time is kept limited by implementing parallelisation schemes on a supercomputer. The adapted model was calibrated and validated using crop and soil information sampled during the 2015 and 2016 harvest periods. Simulated crop yields for the last 4000 years show the strong control of precipitation, while changes in soil thickness following erosion, and to lesser extent re-infiltration of runoff along a slope catena also have a significant impact on crop yield. The latter is especially important in the valleys, where soil and water accumulate. The model results also show that water export to the central valley strongly increased (up to four times) following deforestation and the resulting soil erosion on the hillslopes, turning it into a marsh and rendering it unsuitable for crop cultivation.

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Analysis of the preparation technology of a row seeder for work

E3S Web of Conferences ◽

10.1051/e3sconf/202019301035 ◽

2020 ◽

Vol 193 ◽

pp. 01035

Author(s):

A. Yu. Popov ◽

Noureldin Sharaby ◽

V.V. Zhurba ◽

Е.А. Chaika

Keyword(s):

Mathematical Model ◽

Graph Theory ◽

Crop Yields ◽

Initial Conditions ◽

Critical Path ◽

Economic Factors ◽

Agricultural Crop ◽

Preparation Technology ◽

Urgent Task ◽

Relationship Of

The level of preparation of a row seeder for work and its adaptability to adjustments and settings affects the efficiency of sowing. Analysis of the designs of modern row seeders shows that after-sales service remains a reserve for improving the efficiency of their use, and, therefore, increasing the agricultural crop yields. However, the technologies for the preparation and adjustment row seeders remain poorly understood, and the search for ways to reduce the complexity of maintenance for sowing units is an urgent task. The aim of the study is to build a mathematical model of the technology for checking, adjusting and tuning a row seeder on the basis of graph theory, determining a way to reduce the complexity of servicing maintenance a row seeder in preparation for sowing and justifying a rational way of organizing the seeder setting. Taking into account a number of assumptions and initial conditions, a list of operations for adjusting and setting the seeder is developed. A digraph of a row seeder preparation technology is constructed, which displays the sequence and relationship of the operations of preparation, adjusting and sitting its nodes and mechanisms. The critical path with the greatest time spent on seeder maintenance is determined. The methods for reducing the complexity of maintenance of a row seeder were established and it is recommended that further modernization of the units and mechanisms of the seeder by indicators in terms of suitability for verification, adjustment and setup. The methods of preparing the seeder for work by one performer are considered. The influence of economic factors on the number of performers during maintenance of the seeder before sowing is shown.

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The Main Provisions of the Methodology for Assessing the Convergence of the Results of Mathematical Modeling of Continuous Processes of Avionics Devices and Field Experiments

Mekhatronika Avtomatizatsiya Upravlenie ◽

10.17587/mau.19.680-688 ◽

2018 ◽

Vol 19 (10) ◽

pp. 680-688

Author(s):

V. V. Slatin ◽

M. A. Demkin ◽

A. V. Golubkina

Keyword(s):

Mathematical Modeling ◽

Mathematical Model ◽

Measurement Errors ◽

Field Experiments ◽

Least Squares Method ◽

Regression Line ◽

Flight Tests ◽

Continuous Processes ◽

Statistical Hypotheses ◽

The Mathematical Model

The questions of estimation of convergence of the processes received in single flight tests of an aviation complex and at mathematical modeling are considered. This evaluation is performed based on the methods of analysis of variance and means of verification of statistical hypotheses in decision-making on the convergence of the compared processes. For each of the compared processes, the least squares method determines the regression lines. By methods of mathematical statistics the permissible proximity of regression lines of the compared processes is established and the average regression line equivalent to the mathematical expectation of the analyzed statistical processes is determined. With respect to this line, the variance of deviations of the compared statistical processes is determined and their belonging to the General sample of processes is estimated. This suggests that under normal laws of the distribution of measurement errors there is an adequacy of the processes of the mathematical model of the stages of operation of the aviation complex and the observed processes of these stages during flight tests of the aviation complex under study.

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Contributions of Climate and Soil Properties to Wheat and Maize Yield Based on Long-Term Fertilization Experiments

Plants ◽

10.3390/plants10102002 ◽

2021 ◽

Vol 10 (10) ◽

pp. 2002

Author(s):

Shengbao Wei ◽

Anchun Peng ◽

Xiaomin Huang ◽

Aixing Deng ◽

Changqing Chen ◽

...

Keyword(s):

Soil Properties ◽

Crop Yield ◽

Crop Production ◽

Field Experiments ◽

Crop Yields ◽

Climatic Factors ◽

Maize Yield ◽

Positive Interactions ◽

Climate Factors ◽

Average Contribution

Identifying the contributions of climate factors and soil fertility to crop yield is significant for the assessment of climate change impacts on crop production. Three 20-year field experiments were conducted in major Chinese wheat-maize cropping areas. Over the 20-year period, crop yield and soil properties showed significantly dissimilar variation trends under similar climate changes at each experimental site. The correlation between climatic factors and crop yield varied greatly among the fertilization regimes and experimental sites. Across all the fertilization regimes and the experimental sites, the average contribution rates of soil properties to wheat and maize yield were 45.7% and 53.2%, respectively, without considering climate factors, and 40.4% and 36.6%, respectively, when considering climate factors. The contributions of soil properties to wheat and maize yield variation when considering climate factors were significantly lower than those without considering climate factors. Across all experimental sites and all fertilization regimes, the mean contribution rates of climate factors to wheat and maize yield were 29.5% and 33.0%, respectively. The contribution rates of the interaction of climate and soil to wheat and maize yield were 3.7% and −0.9%, respectively. Under balanced fertilization treatments (NPK and NPKM), the change in the contribution rate of soil properties to wheat or maize yield was not obvious, and the average contribution rates of the interaction of climate and soil to wheat and maize yield were positive, at 14.8% and 9.5%, respectively. In contrast, under unbalanced fertilization treatments (CK and N), the contribution rates of soil properties to wheat or maize yield decreased, and the average contribution rates of the interaction of climate and soil were negative, at −7.4% and −11.2%, respectively. The above results indicate that climate and soil synergistically affected crop yields and that, with the optimization of the fertilization regime, positive interactions gradually emerged.

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