Robust method for estimating grain yield in western Kenya during the growing seasons

2014 ◽  
Vol 6 (2) ◽  
pp. 313-324 ◽  
Author(s):  
Edward M. Mugalavai ◽  
Emmanuel C. Kipkorir
Keyword(s):  
Grain Yield ◽  
Crop Yields ◽  
Climatic Conditions ◽  
Strongly Correlated ◽  
Maize Crop ◽  
Western Kenya ◽  
Growing Seasons ◽  
Seasonal Characteristics ◽  
Aquacrop Model

Uncertainties caused by climate change and population explosion require suitable methods for estimating grain yield during the growing seasons. This paper evaluates the applicability of the AquaCrop model in the region of western Kenya. The objectives of the study were to: simulate the long-term maize crop yields for the region using AquaCrop model for variable climate scenarios, and estimate the expected yield for the ongoing season. Climate was classified into below normal (<x̅ − 1∂), normal (between x̅ − 1∂ and x̅ + 1∂) and above normal (>x̅ + 1∂) conditions based on the Kenya Meteorological Department (KMD) convention. Simulation of grain yield was based on model calibration results, periodic KMD forecasts and the long-term mean for the seasons. The calibrated model is able to estimate both long-term seasonal grain yield and expected harvest for the ongoing season based on climatic conditions that are compared with the long-term seasonal characteristics and complemented by meteorological forecasts. The ongoing season yield simulation was based on persistence theory of Markov processes whose results strongly correlated (r = 0.9) with actual seasonal observed yield.

scholarly journals Replacing Synthetic Nitrogen Fertilizer with Different Types of Organic Materials Improves Grain Yield in China: A Meta-Analysis

Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2429
Author(s):  
Xiaoru Fan ◽  
Zekai Chen ◽  
Zihan Niu ◽  
Ruiyao Zeng ◽  
Jingmin Ou ◽  
...  
Keyword(s):  
Grain Yield ◽  
Nitrogen Fertilizer ◽  
Organic Materials ◽  
Crop Yields ◽  
Meta Analysis ◽  
Chicken Manure ◽  
Agricultural Practice ◽  
Different Types ◽  
Synthetic Nitrogen Fertilizer

Synthetic nitrogen fertilizer substitution (NSS) with different types of organic material is a cleaner agricultural practice for reducing the application of synthetic N input in farmlands while also relieving the environmental issues caused by the discharge of organic wastes. However, the effects of the NSS practice on crop yields, being the primary objective of agricultural activity, is still uncertain in China. This study conducted a meta-analysis to assess the impacts of the NSS practices with different types of organic materials on crop yields. Results showed that the average crop yield was increased by 3.4%, with significant differences under NSS, thereby demonstrating that this practice contributed to improving crop yields, especially of rice and maize. According to published reports, the NSS practices involving chicken manure, pig manure, and crop straw increased crop yields by 4.79, 7.68, and 3.28%, respectively, with significant differences, thus demonstrating the superior effects needed for replacing synthetic N fertilizer. Moreover, substitution ratios (SR) between 0% and 60% could be suggested when using the NSS practice, with the high SR recommended when the original soil fertility was adequate for crops. Considering the long-term effects of applied organic materials, improving the grain yield with the NSS practice should be expected in the long-term. By effectively applying the NSS, this study attempted to scientifically decide on the type of organic materials and the appropriate SR based on the conditions of the soil and the crop. The results provide research information for the development of clean agricultural production and food security in China.

scholarly journals Soybean-corn succession according to seeding date

2018 ◽  
Vol 53 (1) ◽  
pp. 22-29 ◽  
Author(s):  
Rodrigo Arroyo Garcia ◽  
Gessí Ceccon ◽  
Guilherme Afonso da Silva Sutier ◽  
Anna Luiza Farias dos Santos
Keyword(s):  
Grain Yield ◽  
The State ◽  
Southern Region ◽  
Crop Season ◽  
Mato Grosso ◽  
Growing Seasons ◽  
Seeding Date ◽  
Sowing Dates ◽  
Mato Grosso Do Sul

Abstract: The objective of this work was to evaluate the grain yield of soybean and corn cultivars cropped in succession, in different sowing dates. The experiment was carried out in the municipality of Dourados, in the state of Mato Grosso do Sul, Brazil, during three growing seasons, in the sowing dates: 9/15, 10/1, 10/15, and 11/1 for soybean; and 2/1, 2/15, 3/1, and 3/15 for corn. Although soybean yields are strongly affected by the crop season, sowing between late September and early October results in higher long-term yields. Planting corn in succession in mid-February provides the highest grain yield in the southern region of the state Mato Grosso do Sul; therefore, there is no need for an early soybean sowing in September, in order to ensure corn planting in January. Soybean-corn succession in which soybean is sown in early October and corn in mid-February results in higher total grain yields and reduces the climatic risk associated with these crops in the region.

scholarly journals Short- and Long-Term Effects of Lime and Gypsum Applications on Acid Soils in a Water-Limited Environment: 1. Grain Yield Response and Nutrient Concentration

Agronomy ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1213 ◽  
Author(s):  
Geoffrey C. Anderson ◽  
Shahab Pathan ◽  
James Easton ◽  
David J. M. Hall ◽  
Rajesh Sharma
Keyword(s):  
Grain Yield ◽  
Soil Layer ◽  
Acid Soils ◽  
Triticum Aestivum L ◽  
Nutrient Concentrations ◽  
Yield Response ◽  
Long Term Effects ◽  
Grain Yields ◽  
Growing Seasons

Surface (0–10 cm) and subsoil (soil layers below 10 cm) acidity and resulting aluminum (Al) toxicity reduce crop grain yields. In South Western Australia (SWA), these constraints affect 14.2 million hectares or 53% of the agricultural area. Both lime (L, CaCO3) and gypsum (G, CaSO4) application can decrease the toxic effect of Al, leading to an increase in crop grain yields. Within the region, it is unclear if G alone or the combined use of L and G has a role in alleviating soil acidity in SWA, due to low sulfate S (SO4–S) sorption properties of the soil. We present results from three experiments located in the eastern wheatbelt of SWA, which examined the short-term (ST, 2 growing seasons), medium-term (MT, 3 growing seasons), and long-term (LT, 7 growing seasons over 10 years) effects of L and G on grain yield and plant nutrient concentrations. Despite the rapid leaching of SO4–S and no self-liming impact, it was profitable to apply G, due to the significant ST grain yield responses. The grain yield response to G developed even following relatively dry years, but declined over time due to SO4–S leaching. At the LT experimental site had received no previous L application, whereas, at the ST and MT sites, L had been applied by the grower over the previous 5–10 years. For the LT site, the most profitable treatment for wheat (Triticum aestivum L.) grain yield, was the combined application of 4 t L ha−1 with 2 t G ha−1. At this site, the 0–10 cm soil pHCaCl2 was 4.6, and AlCaCl2 was greater than 2.5 mg kg−1 in the 10–30 cm soil layer. In contrast, at the ST and MT sites, the pHCaCl2 of 0–10 cm soil layer was ≥5.5; it was only profitable to apply G to the MT site where the soil compaction constraint had been removed by deep ripping. The use of L increases soil pHCaCl2, resulting in the improved availability of anions, phosphorus (P) in the LT and molybdenum (Mo) at all sampling times, but reduced availability of cations zinc (Zn) in the LT and manganese (Mn) at all sampling. The application of G reduced Mo concentrations, due to the high SO4–S content of the soil.

scholarly journals Change in Maize Final Leaf Numbers and Its Effects on Biomass and Grain Yield across China

Agriculture ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 411
Author(s):  
Wanmao Liu ◽  
Bo Ming ◽  
Ruizhi Xie ◽  
Guangzhou Liu ◽  
Keru Wang ◽  
...  
Keyword(s):  
Grain Yield ◽  
Field Experiments ◽  
Climatic Factors ◽  
Input Parameter ◽  
Climatic Conditions ◽  
Leaf Number ◽  
Maize Crop ◽  
Area Index ◽  
Distribution Ranges ◽  
The Mean

The final leaf number is an important morphological characteristic of maize (Zea mays L.) and is therefore an important input parameter in some maize crop models. In this study, field experiments were conducted from 2013 to 2016 at 23 sites across China, which were located between latitudes of 26°30′ and 46°45′ N, focusing on five modern maize cultivars, in order to determine the amplitude of variation in mean leaf numbers between each cultivar, identify differences between the mean leaf numbers of cultivars under different climatic conditions, and clarify the effects of the differences in final leaf numbers on aboveground dry matter (DM) and grain yield. The results showed that the mean final leaf numbers increased in the order of XY335 < NH101 < ZD909 < ZD958 < DH11 among the five cultivars, with the wide distribution ranges of final leaf numbers being 17.0–23.3 (DH11), 16.7–22.3 (ZD958), 16.7–22.0 (ZD909), 16.7–22.3 (NH101), and 17.0–22.0 (XY335) across all locations. In addition, leaf numbers above and below the primary ear showed the same trends with the mean final leaf numbers for the same cultivars. Many climatic factors were found to significantly affect the final leaf numbers across four maize-growing regions in China, and the result of stepwise regression indicated that the influences of photoperiod and temperature, in particular, were greater than other climatic factors for these cultivars. Finally, there were found to be significant and positive relationships between the final leaf number and (1) the maximum leaf area index (LAImax), (2) DM at both silking and physiological maturity, and (3) grain yield for the same cultivars across all locations. The results of this study are of great importance for guiding future trans-regional maize cultivation and further model calibration.

Irrigation of maize (Zea mays L.) in relation to fertilization in a long-term field experiment

2005 ◽  
Vol 53 (1) ◽  
pp. 41-46 ◽  
Author(s):  
A. Megyes ◽  
J. Nagy ◽  
T. Rátonyi ◽  
L. Huzsvai
Keyword(s):  
Field Experiment ◽  
Crop Production ◽  
Strongly Correlated ◽  
Growing Seasons ◽  
Production Factors ◽  
Maize Yields ◽  
Set Up ◽  
Fertilizer Rates ◽  
Term Field

The objectives of this study were to examine the correlation between factors of great significance for crop production, especially between irrigation and fertilization, and to evaluate the effects of irrigation and fertilization on maize yields over four growing seasons (2001-2004) in a long-term field experiment set up at the Látókép Experimental Station of the Centre for Agricultural Sciences of Debrecen University. The results showed that irrigation and fertilization were strongly correlated with the yield. The effect of irrigation depended on the natural water and nutrient supplies of the soil, and on the specific fertilizer rates. The results indicated that both fertilization and irrigation had a significant effect on the yield. The correlation between the year and the crop production factors was also significant. The yield-increasing effect of irrigation and fertilization differed significantly in the experimental years.

Effets des coupes d'éclaircie et des variations climatiques interannuelles sur la production et la teneur en sucre de la sève d'une érablière

1995 ◽  
Vol 25 (11) ◽  
pp. 1815-1820 ◽  
Author(s):  
David Pothier
Keyword(s):  
Sap Flow ◽  
Sugar Maple ◽  
Basal Area ◽  
Temperature Fluctuations ◽  
Winter Precipitation ◽  
Climatic Conditions ◽  
Sugar Concentration ◽  
Meteorological Variables ◽  
Strongly Correlated

A study was initiated in 1975 on a sugar maple (Acersaccharum Marsh.) stand of the Station forestière de Duchesnay (46°57′N, 71°39′W) to determine the effect of thinning on sap production of sugar maple. From 1975 to 1989, spring sap flow and sugar concentration were measured in 58 sample plots distributed in five blocks within which three intensities of thinning (0, 22, and 35% of the initial basal area) were applied. Thinning intensities only accounted for a small part of the variation in sap volume per tap and sap sugar concentration. However, more than 60% of the variation of these two sap characteristics was related to year-to-year variations. This suggests that sap yield and sap sugar concentration were largely controlled by the different climatic conditions that occurred during these years. Hence, sap yield was strongly correlated with the number of days characterized by temperature fluctuations around 0 °C during springtime and by winter precipitation. Sap sugar concentration was also correlated to the number of days with temperature fluctuating around 0 °C during springtime but all other tested meteorological variables failed to improve this relationship. While thinning intensities did not affect sap yield per tap and sugar concentration, sugar yield per hectare could be improved by thinning over the long term since it increased the potential number of taps per hectare.

RESULTS OF LONG-TERM MONITORING PERENNIAL GRASSES PRODUCTIVENESS WITHIN AGROLANDSCAPE

1970 ◽  
pp. 8-11
Author(s):  
D. А. Ivanov ◽  
O. V. Karaseva ◽  
M. V. Rublyuk
Keyword(s):  
Multiple Regression ◽  
Agricultural Landscape ◽  
Crop Yields ◽  
Land Reclamation ◽  
Climatic Conditions ◽  
Perennial Grasses ◽  
Environmental Crisis ◽  
Regression Equations ◽  
Different Parts

In an era of environmental crisis, monitoring crop yields is of great importance. On this basis, it is possible to develop adaptive methods for land reclamation. The paper considers the results of statistical analysis of monitoring data on the yield of perennial grasses. The studies were conducted on an agroecological transect - a narrow field, 1300 m long, intersecting all the main microlandscape positions of a finite moraine hill. Determination of the productivity of grass stands and parameters of the landscape environment is carried out at sampling points that differ only in natural relation. They are regularly located along the transect at a distance of 40 m from each other. The studies were conducted in 1998 - 2017. For the analysis of climatic parameters, the data of the meteorological station of Tver were used. Processing of the data was carried out by the method of multiple regression based on the package STATGRAPHICS plus. For the agricultural landscape as a whole and its individual parts, multiple regression equations were obtained, describing the influence of parameters of landscape components and long-term fluctuations of agrometeorological indicators on hay yield. The patterns of adaptive reactions of plants to the variability of the properties of the natural environment and agro-climatic conditions within different parts of the finite-moraine ridge are revealed. It is shown that agro-climatic conditions and landscape features of the territory have a significant impact on the grass production process. The negative influence of weather conditions on grasses of the first year of life, as a rule, affects the yield of quite old grass stands. Features of the redistribution of heat and moisture in different parts of the agrolandscape determine the dependence of grass stands on soil waterlogging and inversion processes. It is recommended to carry out drainage within the entire moraine hill, however, at the upper elevations of the agrolandscape, systems of dual regulation of the water-air regime of soils should be applied.

scholarly journals Sensitivity of Winter Barley Yield to Climate Variability in a Pleistocene Loess Area

Climate ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 112
Author(s):  
Kurt Heil ◽  
Sebastian Gerl ◽  
Urs Schmidhalter
Keyword(s):  
Climate Change ◽  
Crop Yields ◽  
Global Climate ◽  
Climatic Conditions ◽  
Winter Barley ◽  
Precipitation Intensity ◽  
Soil Water Storage ◽  
Temperature Threshold ◽  
Late Spring Frost

Global climate change is predicted to increase temperatures and change the distribution of precipitation. However, there is high uncertainty regarding the regional occurrence and intensity of climate change. Therefore, this work examines the effects of climate parameters on the long-term yields of winter barley and assesses the parameters affecting plant development throughout the year and in specific growth phases. The investigation was carried out in an area with Pleistocene loess, a highly fertile site in Germany. The effect of climate on crop yields was modeled with monthly weather parameters and additional indices such as different drought parameters, heat-related stress, late spring frost, early autumn frost, and precipitation-free periods. Residuals and yield values were treated as dependent variables. The residuals were determined from long-term yield trends using the autoregressive integrated moving average (ARIMA) method. The results indicated that temperature and precipitation are significant in all calculations in all variants, but to a lesser degree when considered as sums or mean values, compared with specific indices (e.g., frost-alternating days, the temperature threshold, the precipitation intensity, rain-free days, the early/late frost index, and the de Martonne–Reichel dryness index). The inter-annual variations in crop yields were mainly determined by the prevailing climatic conditions in winter as well as the transition periods from the warmer season to winter and vice versa. The main winter indices were the temperature threshold, frost-alternating days, and precipitation intensity. During the main growth periods, only the precipitation intensity was significant. These findings can be attributed to the high available field water capacity of this site, which overcomes the need for summer precipitation if the soil water storage is replenished during winter.

scholarly journals Sustainable Intensification in Agriculture: An Approach for Making Agriculture Greener and Productive

2021 ◽  
Vol 7 ◽  
pp. 133-150
Author(s):  
Jiban Shrestha ◽  
Subash Subedi ◽  
Krishna Prasad Timsina ◽  
Sudeep Subedi ◽  
Meena Pandey ◽  
...  
Keyword(s):  
Crop Production ◽  
Crop Yields ◽  
Production Systems ◽  
Climatic Conditions ◽  
Sustainable Intensification ◽  
Modern World ◽  
Agronomic Practices ◽  
Farm Mechanization ◽  
Use Efficiency

Sustainable intensification of agriculture is a good approach for reducing the yield gap without exacerbating the current condition of the environmental components, which is a big challenge for agriculture in the modern world. This review provides a summary of the role and approaches of sustainable intensification in agriculture which offer ways to increase crop production and create long-term sustainability in agriculture production. The current demand for food has continued to rise as a result of the world's rapidly increasing population. In order to increase crop/food production, agricultural systems should be intensified by more sustainable practices, as well as by reforming existing production systems/techniques and diversifying them into newer and more profitable enterprises. Despite the heavy use of inputs, farmers have recently been unable to achieve optimal crop yields. The judicious use of agricultural inputs, combined with improved management techniques, is important for advancing sustainable intensification. New scientific techniques in agronomic practices, as well as improved farm mechanization, are helping to boost resource use efficiency in sustainable crop production. The sustainable agricultural intensification is necessary to increase the agricultural productivity under the changing and adverse climatic conditions while maintaining healthy production practices.

Sign in / Sign up

Export Citation Format

Share Document