scholarly journals Farmer's Bookshelf Information System for Predicting Phosphorus Requirements of Some Hawii Soils

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 903E-903
Author(s):  
Kent D. Kobayashi ◽  
H.C. Bittenbender ◽  
N.V. Hue
Keyword(s):  
Information System ◽  
Soil Solution ◽  
Crop Production ◽  
Maximum Yield ◽  
P Value ◽  
Aluminum Oxides ◽  
P Fertilizer ◽  
Alumino Silicate ◽  
Soil Solution P ◽  
Phosphorus Requirements

Most soils of Hawaii contain high amounts of iron- and aluminum oxides or amorphous alumino silicate clays, which react strongly with P making it virtually unavailable for plant uptake. Acceptable crop production is not possible unless adequate P fertilizers are applied. Growers need to know if a soil needs P and if so how much. The Farmer's Bookshelf hypermedia information system, which runs under the software HyperCard, can quickly provide these answers. A screen is displayed in which the soil series and the crop to be grown are specified through pull-down menus. The user then enters the Truogextractable P value of the soil and clicks on a “Calculate” button. The soil solution P value is calculated and compared to the minimum soil solution P needed to adequately grow the crop (80% to 95% of maximum yield). If the value is greater than the minimum value, then P fertilizer is not recommended. Otherwise, the program recommends the amount of fertilizer to add as P, P2O5, and treble superphosphate in pound per 1000 square feet and pound per acre. The recommendations, presented in a table, can then be printed for clientele use.

scholarly journals Soil solution phosphorus turnover: derivation, interpretation, and insights from a global compilation of isotope exchange kinetic studies

2017 ◽  
Author(s):  
Julian Helfenstein ◽  
Jannes Jegminat ◽  
Timothy I. McLaren ◽  
Emmanuel Frossard
Keyword(s):  
Soil Solution ◽  
Field Experiments ◽  
Solid Phase ◽  
Negative Relationship ◽  
Kinetic Studies ◽  
Terrestrial Ecosystems ◽  
P Fertilizer ◽  
Exchange Kinetic ◽  
Soil Solution P

Abstract. The exchange rate of inorganic phosphorus (P) between the soil solution and solid phase, also known as soil solution P turnover, is essential for describing the kinetics of bioavailable P. While soil solution P turnover (Km) can be determined by tracing radioisotopes in a soil-solution system, few studies have done so. We believe that this is due to a lack of understanding on how to derive Km from isotopic exchange kinetic (IEK) experiments, a widespread form of radioisotope dilution study. Here, we provide a derivation of calculating Km using parameters obtained from IEK experiments. We then calculated Km for 217 soils from published IEK experiments in terrestrial ecosystems, and also for that of 18 long-term P fertilizer field experiments. Analysis of the global compilation dataset revealed a negative relationship between concentrations of soil solution P and Km. Furthermore, Km buffered isotopically exchangeable P in soils with low concentrations of soil solution P. This finding was supported by an analysis of long-term P fertilizer field experiments, which revealed a negative relationship between Km and phosphate buffering capacity. Our study thus highlights the potential of Km for future studies – not only for P, but also for other environmentally-relevant, strongly-sorbing elements with radioisotopes such as zinc, cadmium, nickel, arsenic, or uranium.

scholarly journals Soil Temperature Influences the Response of Lettuce to Phosphorus

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 864A-864
Author(s):  
B.R. Gardner ◽  
C.A. Sanchez
Keyword(s):  
Soil Temperature ◽  
Soil Solution ◽  
Maximum Yield ◽  
Yield Response ◽  
Temperature Sensitive ◽  
Planting Dates ◽  
Soil P ◽  
Stage Of Development ◽  
Soil Temperatures ◽  
Soil Solution P

Lettuce is planted in the southwestern U.S. desert from September through December and harvested from November through April each year. During this period mean soil temperatures range from 7 to 30C. Lettuce produced on desert soils shows a large yield response to P. Soil solution P is replenished by desorption from the labile soil P fraction and this process is temperature sensitive. A field study was conducted over 6 years to evaluate the response of lettuce to soil solution P levels under different ambient soil temperature regimes. The soil temperatures under which lettuce was grown were varied each year by altering planting dates. Soil solution P levels were established and maintained each season using P sorption isotherm methodology. Lettuce responded to P in all experiments. Phosphorus levels required for maximum yield varied with each experiment. Soil P levels required for optimal yield were best correlated to mean soil temperatures during the last 20 days before harvest. Lettuce accumulates over 70% of its P during the heading stage of development and it is likely that during this period of rapid growth and nutrient uptake, solution P becomes limiting when soil temperatures are cool.

Effect of depth and lime or phosphorus-fertilizer applications on the soil solution chemistry of some New Zealand pastoral soils

Soil Research ◽  
1995 ◽  
Vol 33 (3) ◽  
pp. 461 ◽  
Author(s):  
DM Wheeler ◽  
DC Edmeades
Keyword(s):  
Soil Solution ◽  
Soil Ph ◽  
Maximum Yield ◽  
Solution Chemistry ◽  
Phosphorus Fertilizer ◽  
Solution Ph ◽  
Soil Solutions ◽  
P Fertilizer ◽  
P Rate ◽  
Mn Concentrations

Thirteen trails were sampled to investigate the effects of depth, or the surface application of lime and phosphorus (P) fertilizer, on solution composition. Soil solutions were extracted by centrifuge from field moist soils within 24 h of sampling. Solution Ca, Mg, Na and K, Al, Mn and Fe concentrations generally decreased and Al, Mn and Fe concentrations generally increased with depth; although exceptions occurred. The largest decrease occurred in the first 25-50 mm of soil. Higher solution Al concentrations occurred in a band at a depth of between 50 and 100 mm in some soils. Lime generally increased solution pH and solution Ca, Mg and HCO3 concentrations, and reduced solution Al, Fe and Mn concentrations in the topsoils. In one soil (Matapiro silt loam) 2 years after lime was applied, lime increased solution pH down to a depth of 100 mm, Ca and HCO3 down to 75 mm and Mg down to 50 mm. Lime also decreased solution Al and Mn down to 75 mm and Fe down to 50 mm. In one series of trials, lime increased solution Ca concentrations at a depth of 50-100 mm 4 years after application in six out of the eight sites. In the same trial series, the application of P fertilizer increased solution P concentrations at 0-50 mm from a mean of 5 �M in the no-added P plots up to a mean of 56 �M at the highest P rate. The highest solution P concentration recorded was 194 �M. The increase in solution P concentrations for a given application of fertilizer P varied from 0.05 to 1.03 �M P per kg P ha-1 applied. Maximum pasture yield and 90% maximum yield occurred when solution P concentrations were about 28 and 14 �M respectively. Solution P concentrations determined from P adsorption isotherms were not a good indicator of solution P concentrations measured in soil. Solution pH was higher than soil pH (1:2.5 soil:water ratio, 2 h equilibration) with a solution pH of 6.0 corresponding to a soil pH in water of about 5.2.

scholarly journals Soil solution phosphorus turnover: derivation, interpretation, and insights from a global compilation of isotope exchange kinetic studies

2018 ◽  
Vol 15 (1) ◽  
pp. 105-114 ◽  
Author(s):  
Julian Helfenstein ◽  
Jannes Jegminat ◽  
Timothy I. McLaren ◽  
Emmanuel Frossard
Keyword(s):  
Soil Solution ◽  
Field Experiments ◽  
Solid Phase ◽  
Negative Relationship ◽  
Data Set ◽  
P Fertilizer ◽  
Exchange Kinetic ◽  
Soil Solution P ◽  
Kinetics Of

Abstract. The exchange rate of inorganic phosphorus (P) between the soil solution and solid phase, also known as soil solution P turnover, is essential for describing the kinetics of bioavailable P. While soil solution P turnover (Km) can be determined by tracing radioisotopes in a soil–solution system, few studies have done so. We believe that this is due to a lack of understanding on how to derive Km from isotopic exchange kinetic (IEK) experiments, a common form of radioisotope dilution study. Here, we provide a derivation of calculating Km using parameters obtained from IEK experiments. We then calculated Km for 217 soils from published IEK experiments in terrestrial ecosystems, and also that of 18 long-term P fertilizer field experiments. Analysis of the global compilation data set revealed a negative relationship between concentrations of soil solution P and Km. Furthermore, Km buffered isotopically exchangeable P in soils with low concentrations of soil solution P. This finding was supported by an analysis of long-term P fertilizer field experiments, which revealed a negative relationship between Km and phosphate-buffering capacity. Our study highlights the importance of calculating Km for understanding the kinetics of P between the soil solid and solution phases where it is bioavailable. We argue that our derivation can also be used to calculate soil solution turnover of other environmentally relevant and strongly sorbing elements that can be traced with radioisotopes, such as zinc, cadmium, nickel, arsenic, and uranium.

scholarly journals How Can We Realize Sustainable Development Goals in Rocky Desertified Regions by Enhancing Crop Yield with Reduction of Environmental Risks?

2021 ◽  
Vol 13 (9) ◽  
pp. 1614
Author(s):  
Boyi Liang ◽  
Timothy A. Quine ◽  
Hongyan Liu ◽  
Elizabeth L. Cressey ◽  
Ian Bateman
Keyword(s):  
Sustainable Development ◽  
Crop Yield ◽  
Crop Production ◽  
Sustainable Development Goals ◽  
Positive Impact ◽  
Total Yield ◽  
Maximum Yield ◽  
Guizhou Province ◽  
Crop Species ◽  
Development Goals

To meet the sustainable development goals in rocky desertified regions like Guizhou Province in China, we should maximize the crop yield with minimal environmental costs. In this study, we first calculated the yield gap for 6 main crop species in Guizhou Province and evaluated the quantitative relationships between crop yield and influencing variables utilizing ensembled artificial neural networks. We also tested the influence of adjusting the quantity of local fertilization and irrigation on crop production in Guizhou Province. Results showed that the total yield of the selected crops had, on average, reached over 72.5% of the theoretical maximum yield. Increasing irrigation tended to be more consistently effective at increasing crop yield than additional fertilization. Conversely, appropriate reduction of fertilization may even benefit crop yield in some regions, simultaneously resulting in significantly higher fertilization efficiency with lower residuals in the environment. The total positive impact of continuous intensification of irrigation and fertilization on most crop species was limited. Therefore, local stakeholders are advised to consider other agricultural management measures to improve crop yield in this region.

Long-term effect of cropping system and nitrogen and phosphorus fertilizer on production and nitrogen economy of grain crops in a Brown Chernozem

2005 ◽  
Vol 85 (1) ◽  
pp. 81-93 ◽  
Author(s):  
C. A. Campbell ◽  
R. P. Zentner ◽  
F. Selles ◽  
P. G. Jefferson ◽  
B. G. McConkey ◽  
...  
Keyword(s):  
Water Use ◽  
Environmental Sustainability ◽  
Crop Production ◽  
N Uptake ◽  
Yield Response ◽  
Average Response ◽  
Nitrogen And Phosphorus ◽  
N Yield ◽  
P Fertilizer

Assessment of the long-term impact of fertilizers and other management factors on crop production and environmental sustainability of cropping systems in the semi-arid Canadian prairies is needed. This paper discusses the long-term influence of N and P fertilizers on crop production, N uptake and water use of hard red spring wheat (Triticum aestivum L.), and the effect of the preceding crop type [flax (Linum usitatissimum L.) and fall rye (Secale cereale L.)] on wheat grown on a medium-textured, Orthic Brown Chernozem at Swift Current, Saskatchewan. We analysed 36 yr of results (1967–2002) from eight crop rotation-fertility treatments: viz., fallow-wheat receiving N and P (F-W, N + P), three F-W-W treatments fertilized with (i) N + P, (ii) P only, and (iii) N only; two other 3-yr mixed rotations with N + P (i) F-flax-W (F-Flx-W) and (ii) F-fall rye-W (F-Rye-W); and two continuous wheat rotations (Cont W), one receiving N + P and the other only P. Growing season weather conditions during the 36-yr period were near the long-term mean, but the first 22 yr were generally drier than normal while the last 14 yr (1989–2002) had average to above-average growing conditions. This was partly responsible for grain and N yield being greater in the latter period than in the first 22 yr. The 36-yr average response of wheat grown on fallow to P fertilizer was 339 kg ha-1, while the response to N fertilizer over this period was only 123 kg ha-1. The 36-yr average response of wheat grown on stubble to N was 344 kg ha-1 for F-W-(W) and 393 kg ha-1 for Cont W. Neither flax nor fall rye influenced the yield response of the following wheat crops. Annualized grain production for F-W (N + P), F-W-W (+ N) and F-W-W (+ P) rotations were similar (1130 kg ha-1 yr-1); this was about 15% lower than for F-W-W (N + P), 40% lower than for Cont W (N + P), and 5% lower than for Cont W (+ P). Annualized aboveground N yield for Cont W (N + P) was 57% higher than for Cont W (+ P). Regressions were developed relating straw to grain yields for wheat, flax and fall rye. The amount of NO3-N left in the soil was directly related to amount of N applied and inversely to N removed in the crop. Thus, F-(W)-W (+ N) left about 28% more NO3-N in the rooting zone than F-(W)-W (N + P), while F-W-(W) (N + P) left 20% more than F-W-(W) (+ P), and Cont W (N + P) left 39% more than Cont W (+ P). F-Rye-W (N + P) left much less NO3-N in the soil than any other fallow-containing system and similar amounts to Cont W (N + P). Key words: Yields, grain protein, N and P fertilizer, straw/grain regressions, water use, soil nitrate

scholarly journals An External Agribusiness Risk Analysis Using KBDI: A Case of Veldfires in the Northern Territory of Australia

2020 ◽  
Vol 3 (1) ◽  
pp. 37
Author(s):  
Toyi Maniki Diphagwe ◽  
Bernard Moeketsi Hlalele ◽  
Dibuseng Priscilla Mpakathi
Keyword(s):  
Time Series ◽  
Probability Distribution ◽  
Crop Production ◽  
Time Series Data ◽  
Northern Territory ◽  
Return Level ◽  
Series Data ◽  
Burned Area ◽  
Trend Test ◽  
P Value

The 2019/20 Australian bushfires burned over 46 million acres of land, killed 34 people and left 3500 individuals homeless. Majority of deaths and buildings destroyed were in New South Wales, while the Northern Territory accounted for approximately 1/3 of the burned area. Many of the buildings that were lost were farm buildings, adding to the challenge of agricultural recovery that is already complex because of ash-covered farmland accompanied by historic levels of drought. The current research therefore aimed at characterising veldfire risk in the study area using Keetch-Byram Drought Index (KBDI). A 39-year-long time series data was obtained from an online NASA database. Both homogeneity and stationarity tests were deployed using a non-parametric Pettitt’s and Dicky-Fuller tests respectively for data quality checks. Major results revealed a non-significant two-tailed Mann Kendall trend test with a p-value = 0.789 > 0.05 significance level. A suitable probability distribution was fitted to the annual KBDI time series where both Kolmogorov-Smirnov and Chi-square tests revealed Gamma (1) as a suitably fitted probability distribution. Return level computation from the Gamma (1) distribution using XLSTAT computer software resulted in a cumulative 40-year return period of moderate to high fire risk potential. With this low probability and 40-year-long return level, the study found the area less prone to fire risks detrimental to animal and crop production. More agribusiness investments can safely be executed in the Northern Territory without high risk aversion.

Yield or profit: alternatives to the development of national crop production

Ekonomika APK ◽  
2021 ◽  
Vol 316 (2) ◽  
pp. 15-25
Author(s):  
Dmytro Zherlitsyn ◽  
Andrii Skrypnyk ◽  
Nataliia Klymenko ◽  
Kateryna Tuzhyk
Keyword(s):  
Grain Yield ◽  
Crop Production ◽  
Maximum Yield ◽  
Target Function ◽  
Optimization Methods ◽  
Econometric Analysis ◽  
Practical Significance ◽  
Moderate Increase ◽  
Production Research ◽  
The Impact

The purpose of the article is to determine with the help of econometric and optimization methods the priority strategies of agrarian business in the field of crop production and to compare with the existing leaders in the use of innovations in the field of crop production. Research methods. The study is based on the use of econometric analysis methods to build trends in grain yield dynamics in leading countries in the use of innovative agricultural technologies and optimization methods for the study of dominant strategies used by agricultural enterprises in crop production. Research results. As a result of using the declining marginal grain yield depending on the amount of costs, which are determined by the cost of importing technology per 1 ha, the optimal cost values for both maximum yield and maximum profit. It is shown that at certain time intervals the costs of farmers were excessively high not only in terms of profit optimization but also to optimize yields. It is assumed that taking into account the latest innovation trends, agribusiness will move to a strategy of profit maximization Scientific novelty. As a result of econometric analysis it is shown that the use as a target function of yield leads to a significant increase in the variability of this indicator, while a moderate increase in yield is accompanied by significantly less variability. Quantitative indicators of the impact of climate risks on grain yields in Ukraine have been obtained, which explain approximately 50% of the variance in the grain yield indicator in Ukraine. Practical significance. It is shown that the representation of marginal yield in the form of a decreasing linear function is confirmed in practice. Further research, which in the presence of detailed information on the production processes of individual enterprises can be conducted by panel regression (observation points are spaced in space and time), can provide a more detailed picture of the efficiency of individual production components in their areas of interaction. Tabl.: 4. Figs.: 3. Refs.: 19.

scholarly journals Effect of Different Levels of I.B.A Concentration on Clonal Propagation of Eucalyptus Species in Ghana West Africa.

2020 ◽  
Author(s):  
Nana Yaw Sarpong ◽  
Frank Ofori Agyemang ◽  
Daniel E.K.A Siaw ◽  
Essakku Menason
Keyword(s):  
Butyric Acid ◽  
Survival Rates ◽  
Maximum Yield ◽  
Eucalyptus Grandis ◽  
Field Performance ◽  
Cost Effective ◽  
P Value ◽  
Eucalyptus Species ◽  
Eucalyptus Urophylla ◽  
Four Levels

Abstract BackgroundIncreasing global wood demands have necessitated an overall push for cost-effective methods of vegetative propagation using cuttings. Vegetative plant propagation through cuttings although a breakthrough is mostly hampered with the inability of cuttings to root effectively to achieve maximum yield. Ten clones each of Eucalyptus grandis x Eucalyptus urophylla (E. grandis x E. urophylla) and Eucalyptus pellita (E. pellita) were treated with Indole-3-butyric acid (IBA) concentrations of 0 ppm (control), 2000 ppm, 3000 ppm and 4000 ppm respectively.ResultsOverall mean survival of cuttings was low (< 50%) for all concentrations of IBA used in this research. Survival rates of individual clones however varied from clone to clone. E. grandis x E. urophylla cuttings had the highest mean survival (43.39%) when treated with 2000 ppm of IBA and lowest mean survival (37.86%) when treated with 0 ppm. Results from the survival rates of E. grandis × E. Urophylla and Eucalyptus pellita cuttings were subjected to an Analysis of Variance test to identify any significant differences between hormone concentration and cutting survival. ANOVA results indicated that differences between cutting–IBA concentrations for E. grandis × E. Urophylla were significant (p=1.85x10-08) which is lower than standard p value (p=0.05) used in the test.For E. pellita (P) cuttings the highest mean survival (27.14%) was achieved when treated with 2000 ppm of Indole-3-butyric acid (IBA). Individual clones however showed significant differences in survival. E. pellita clone P2 achieved the highest survival (52.68%) in the control experiment (0 ppm). Some clones i.e P51 and P82 achieved survivals of less than 10% in all four levels of IBAConclusionThe best surviving Eucalyptus grandis x Eucalyptus urophylla clone (GH11) achieved a mean survival rate of 75% when the GH11 basal cutting was treated with 2000 ppm IBA. The results indicated that the production of clones with survival rates of less than 20% should be discarded since it makes no economic sense clones with survival rates of more than 40% should be planted out in the field to compare field performance with greenhouse survival.

scholarly journals Diagnosa Preeklampsia pada Ibu Hamil Menggunakan Sistem Informasi Berbasis Web

2019 ◽  
Vol 2 (2) ◽  
pp. 18-27
Author(s):  
Fajaria Nur Aini ◽  
Melyana Nurul Widyawati ◽  
Bedjo Santoso
Keyword(s):  
Information System ◽  
Information Systems ◽  
Pregnant Women ◽  
Community Health Center ◽  
Intervention Group ◽  
Diagnostic System ◽  
Control Group ◽  
P Value ◽  
Web Based ◽  
Time Required

This study aims to produce a preeclampsia diagnostic system online and to determine the difference in the speed of time required to diagnose preeclampsia using a web-based information system with a manual system. This research method is to arrange a framework with a quasi experimental research design with a post test only with control group. This research was conducted at the Community Health Center. The results showed that the majority of respondents were healthy pregnant women namely in the intervention group of 20 pregnant women (30.30%) and in the control group of 15 pregnant women (22.73%). The smallest number of diagnoses is in the case of superimposed preeclampsia. Web-based information systems are also able to increase diagnostic speeds to 7.21%. Statistical test results using the Independent T-Test obtained a P-value of 0.041 <0.05 (α). Conclusion, there is a difference in the time of diagnosis of preeclampsia using a web-based information system with a manual system.   Keywords: Diagnosis, Preeclampsia, Information Systems, Web

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