Impact of Irrigation and Hail on Palmer Amaranth (Amaranthus Palmeri) in Corn

2008 ◽  
Vol 22 (3) ◽  
pp. 448-452 ◽  
Author(s):  
Randall S. Currie ◽  
Norman L. Klocke
Keyword(s):  
Linear Models ◽  
Palmer Amaranth ◽  
Economic Returns ◽  
Corn Plant ◽  
Economic Return ◽  
Area Index ◽  
Irrigation Level ◽  
Dose Response Study ◽  
The Impact

In 2005 a hailstorm struck a long-term dose–response study of irrigation requirements and corn plant populations. This misfortune occurred again in 2006 at approximately the same growth stage. Therefore, the objectives of the studies were redirected to measure the impact of actual hail events on corn leaf area index (LAI) and the competitive interaction of escaped Palmer amaranth populations induced by hail across different levels of irrigation and corn populations. In 2005, the study treatment with the lowest corn population and level of irrigation had twice the Palmer amaranth biomass (PABM) at corn harvest compared with the highest corn population and irrigation level. Corn LAI produced simple linear models that predicted both corn grain yield and PABM. In 2007, the nonhail year, PABM was depressed 4- to 15-fold compared with hail years. PABM declined linearly from 417 kg/ha at the lowest level of irrigation and corn population to 48 kg/ha at the highest level of irrigation and corn plant population. Although economic return per increment of irrigation declined in both hail years, the trends in economic returns were still positive. This suggests that a producer with similar conditions should continue to irrigate even though his or her rate of economic return is reduced.

Influence of timing of Palmer amaranth control in dicamba-resistant cotton on yield and economic return

2020 ◽  
Vol 34 (5) ◽  
pp. 682-688
Author(s):  
Matthew D. Inman ◽  
David L. Jordan ◽  
Matthew C. Vann ◽  
Andrew T. Hare ◽  
Alan C. York ◽  
...  
Keyword(s):  
Resistance Management ◽  
Residual Activity ◽  
Palmer Amaranth ◽  
Cotton Yield ◽  
Economic Returns ◽  
Economic Return ◽  
Early Season ◽  
Cotton Belt ◽  
The U.S ◽  
Made In

AbstractGlyphosate-resistant (GR) Palmer amaranth continues to be challenging to control across the U.S. cotton belt. Timely application of POST herbicides and herbicides applied at planting or during the season with residual activity are utilized routinely to control this weed. Although glyphosate controls large Palmer amaranth that is not GR, herbicides such as glufosinate used in resistance management programs for GR Palmer amaranth must be applied when weeds are small. Dicamba can complement both glyphosate and glufosinate in controlling GR and glyphosate-susceptible (GS) biotypes in resistant cultivars. Two studies were conducted to determine Palmer amaranth control, weed biomass, and cotton yield, as well as to estimate economic net return when herbicides were applied 2, 3, 4, and 5 wk after planting (WAP). In one experiment POST-only applications were made. In the second experiment PRE herbicides were included. In general, Palmer amaranth was controlled at least 98% by herbicides applied at least three times regardless of timing of application or herbicide sequence. Glyphosate plus dicamba applied at 4 and 5 WAP controlled Palmer amaranth similarly compared to three applications by 8 WAP; however, yield was reduced 23% because of early-season interference. The inclusion of PRE herbicides benefited treatments that did not include herbicides applied 2 or 3 WAP. Glyphosate plus dicamba applied as the only herbicides 5 WAP provided 69% control of Palmer amaranth. PRE herbicides increased control to 96% for this POST treatment. Economic returns were similar when three or more POST applications were applied, with or without PRE herbicides.

Methods to determine the impact of rainfall on fuels and burned area in southern African savannas

2010 ◽  
Vol 19 (6) ◽  
pp. 774 ◽  
Author(s):  
S. Archibald ◽  
A. Nickless ◽  
R. J. Scholes ◽  
R. Schulze
Keyword(s):  
Southern Africa ◽  
Linear Models ◽  
Burned Area ◽  
Rainfall Index ◽  
Occurrence Data ◽  
Accumulated Rainfall ◽  
Input Variables ◽  
The Impact ◽  
The Relationship

In southern African savannas, grass production, and therefore the annual extent of fire, is highly dependent on rainfall. This response has repeatedly been noted in the literature but authors used different input variables and modelling approaches and the results are not comparable. Using long-term fire occurrence data from six protected areas in southern Africa we tested various methods for determining the relationship between antecedent rainfall and burned area. The types of regression model, the most appropriate index of accumulated rainfall, and the period over which to calculate annual burned area were all investigated. The importance of accumulating rainfall over more than one growing season was verified in all parks – improving the accuracy of the models by up to 30% compared with indices that only used the previous year’s rainfall. Up to 56% of the variance in burned area between years could be explained by an 18-month accumulated rainfall index. Linear models and probit models performed equally well. The method suggested in this paper can be applied across southern Africa. This will improve our understanding of the drivers of interannual variation in burned area in this globally important fire region.

scholarly journals Impact of Weed Management on Peanut Yield and Weed Populations the Following Year

2019 ◽  
Vol 46 (2) ◽  
pp. 182-190
Author(s):  
A.T. Hare ◽  
D.L. Jordan ◽  
R.G. Leon ◽  
K.L. Edmisten ◽  
A.R. Post ◽  
...  
Keyword(s):  
Weed Management ◽  
Field Studies ◽  
Palmer Amaranth ◽  
Herbicide Application ◽  
Economic Return ◽  
Common Ragweed ◽  
Arachis Hypogaea L ◽  
Previous Season ◽  
Rotational Crop ◽  
The Impact

ABSTRACT Field studies were conducted in 2016 and 2017 at two locations in North Carolina to evaluate common ragweed (Ambrosia artemiisifolia L.) (Lewiston-Woodville) and Palmer amaranth (Amanthus palmeri S. Wats) control (Rocky Mount), peanut (Arachis hypogaea L.) yield, and estimated economic return when herbicides were applied postemergence (POST) at 2 or 6 weeks after planting (WAP); 2 and 4 WAP; 4 and 6 WAP; and 2, 4, and 6 WAP. During the following growing season, cotton (Gossypium hirsutum L.) was planted directly into the same plots to determine the impact of weed management during the previous season on weed density. In absence of herbicides, peanut yield was 880 and 1110 kg/ha at Lewiston-Woodville and Rocky Mount, respectively. When weed control depended on a single herbicide application, yield ranged from 1760 to 2660 kg/ha at Lewiston-Woodville, and 2080 to 2480 kg/ha at Rocky Mount. When herbicides were applied twice, peanut yield ranged from 2690 to 3280 kg/ha at Lewiston-Woodville and 3420 to 3840 kg/ha at Rocky Mount. The greatest yields were recorded when herbicides were applied two or three times. Applying herbicides increased the estimated economic return of peanut compared to the non-treated control (NTC). In cotton the following year, common ragweed populations at Lewiston-Woodville were greater following the NTC or a single herbicide application 2 WAP compared to more intensive herbicide programs. Palmer amaranth density at Rocky Mount the following year in cotton was not affected by weed management the previous year in peanut. These results illustrate the relative importance of timing and duration of weed management for peanut and how they influence weed emergence in the following cotton rotational crop.

scholarly journals Harvesting Charges for Florida Citrus: Picking, Roadsiding, and Hauling, 2015/16

EDIS ◽  
2017 ◽  
Vol 2017 (1) ◽  
Author(s):  
Ariel Singerman ◽  
Marina Burani-Arouca ◽  
Stephen H. Futch
Keyword(s):  
The State ◽  
Economic Returns ◽  
Economic Return ◽  
Florida Citrus ◽  
The Impact ◽  
Harvesting Costs

This article summarizes the harvesting charges for citrus during the 2015/16 season and it also documents the changes in harvesting costs as the impact of HLB increases across the state. On-tree prices are the basis for establishing the economic return to citrus growers. Therefore, the usefulness of the estimates we presented resides in that they provide the basis for computing on-tree prices from delivered-in prices; allowing to compute the change in citrus growers’ economic returns as the industry adapts to remain profitable.

scholarly journals Characterizing uncertainty in the hydraulic parameters of oil sands mine reclamation covers and its influence on water balance predictions

2020 ◽  
Vol 24 (2) ◽  
pp. 735-759 ◽  
Author(s):  
M. Shahabul Alam ◽  
S. Lee Barbour ◽  
Mingbin Huang
Keyword(s):  
Water Balance ◽  
Oil Sands ◽  
Monitoring Site ◽  
Hydraulic Parameters ◽  
Oil Sand ◽  
Water Balance Components ◽  
Area Index ◽  
Parameter Values ◽  
The Impact

Abstract. One technique to evaluate the performance of oil sands reclamation covers is through the simulation of long-term water balance using calibrated soil–vegetation–atmosphere transfer models. Conventional practice has been to derive a single set of optimized hydraulic parameters through inverse modelling (IM) based on short-term (<5–10 years) monitoring datasets. This approach is unable to characterize the impact of variability in the cover properties. This study utilizes IM to optimize the hydraulic properties for 12 soil cover designs, replicated in triplicate, at Syncrude's Aurora North mine site. The hydraulic parameters for three soil types (peat cover soil, coarse-textured subsoil, and lean oil sand substrate) were optimized at each monitoring site from 2013 to 2016. The resulting 155 optimized parameter values were used to define distributions for each parameter/soil type, while the progressive Latin hypercube sampling (PLHS) method was used to sample parameter values randomly from the optimized parameter distributions. Water balance models with the sampled parameter sets were used to evaluate variations in the maximum sustainable leaf area index (LAI) for five illustrative covers and quantify uncertainty associated with long-term water balance components and LAI values. Overall, the PLHS method was able to better capture broader variability in the water balance components than a discrete interval sampling method. The results also highlight that climate variability dominates the simulated variability in actual evapotranspiration and that climate and parameter uncertainty have a similar influence on the variability in net percolation.

scholarly journals Family planning: Smartest investment for achieving the Sustainable Developments Goals for Pakistan

2021 ◽  
Author(s):  
Muhammad Wazir ◽  
Yilma Melkamu Alazar ◽  
Bakhtior Kadirov
Keyword(s):  
Family Planning ◽  
Contraceptive Use ◽  
Universal Access ◽  
National Development ◽  
Cost Effective ◽  
Economic Returns ◽  
The Sustainable Development ◽  
Development Goals ◽  
The Impact

Investing in voluntary family planning services andcommodities is a cost-effective intervention for socioeconomicdevelopment. Every dollar spent on familyplanning results in reductions in child and maternaldeaths, returns in savings in other development areas, andenvironmental benefits. Investments in family planningyield demonstrated social and economic returns in allsectors - food, water, health, and economic development.Our analysis suggests that achieving universal access tocontraception could contribute in the long term toachieving some of the Sustainable Development Goals(SDGs). We applied the Family Planning-SustainableDevelopment Goals (FP-SDGs) Model that quantifies thebenefits voluntary contraceptive use offers for realizing 13of the SDG indicators which are related to 7 out of the 17SDGs Goals. The model unravelling the multi-sectoralbenefits of contraceptive use and shows that familyplanning can accelerate progress across the 7 SDG.Further, it shows that family planning does not onlyempower women to choose the number, timing, andspacing of their pregnancies but also touches on manymultisectoral determinants vital to sustainabledevelopment. We show that in the case of Pakistan,without universal access to family planning andreproductive health, the impact and effectiveness of otherinterventions will be less, will cost more, and will takelonger to achieve. In the end, we put some keyrecommendations to prioritize family planning as one ofthe strategic national development investments.

Public and Private Returns to Investing in Nutrition

2015 ◽  
pp. 404-433 ◽  
Author(s):  
Harold Alderman ◽  
David E. Sahn
Keyword(s):  
Multiple Channels ◽  
Economic Returns ◽  
Public And Private ◽  
Individual Level ◽  
Microeconomic Analysis ◽  
Cross Country ◽  
The Individual ◽  
The Life Course ◽  
The Impact

The authors examine the impact of nutrition on productivity at both the micro and macro levels and conclude that large economic returns to investing in nutrition. These can be measured at both the individual level as well as through economy-wide indicators such as aggregate incomes and gross domestic product. The evidence comes from a range of methodologies and disciplines, including the work of economic historians, cross-country models, microsimulation, and structural and experimental microeconomic analysis. The positive economic returns to investing in nutrition operate through multiple channels. These range from literature that shows that in utero and early-life nutritional inputs contribute positively to various economic metrics through a range of mediating factors (such as increased stature, improved cognition, and savings associated with reduced morbidity and mortality across the life course) to evidence from long-term historical studies that improved nutrition contributes to large improvements in per capita growth.

Production and economic returns from Merino weaner sheep subjected to four frequencies of anthelmintic administration in East Gippsland, Victoria

1987 ◽  
Vol 27 (6) ◽  
pp. 759 ◽  
Author(s):  
NJ Barton ◽  
IP McCausland
Keyword(s):  
Cost Price ◽  
Parasite Control ◽  
Economic Returns ◽  
Economic Return ◽  
Wool Production ◽  
Treatment Groups ◽  
Wool Growth ◽  
Price Range

In East Gippsland. Victoria. 4 treatment groups, designated 'weekly' (W), 'high' (H), 'low' (L). and 'salvage' (S), each consisting of 3 subgroups of 10 Merino weaner sheep, were given different numbers of anthelmintic doses during 1978, 1979 and 1980. The doses were respectively 5 1, 5 1, 50 (W); 9,9, 12 (H); 3,4. 6 (L); and 1, 3, 2 (S). Both anthelmintics were administered according to the manufacturers' recommendations. Subgroups were grazed on separate 1 ha plots and rotated between plots within treatments at 2-week intervals in an attempt to eliminate between paddock differences. Sheep were replaced annually. These programs resulted in major differences in wool production and final liveweight between groups. Over the 3 years of the experiment, sheep dosed frequently grew heavier (P< 0.05) and produced more wool than - did sheep in the Land S groups. Mean final liveweights for the W, H, L, and S groups respectively were 53.6, 51.4.47.0, and 46.4 kg (l.s.d. [P= 0.051 = 3.5 kg). Corresponding figures for wool growth were 5.96, 5.62. 5.07, and 5.17 kg (l.s.d. [P = 0.051 = 0.60). Mortality in the W (5.6%) and H (22%) groups was also lower than in the L (18.9%) and S (27.8%) groups. The H group gave the highest economic return of $21.81 per sheep compared with $17.61 (W group), $16.3 1 (L) and $15.06 (S group). This advantage was maintained throughout a wide cost-price range. However. as both the W and H programs selected strongly for strains of nematodes resistant to anthelmintics. anthelmintic therapy alone cannot be relied upon for long-term parasite control.

Suppressed, but Not Forgotten

2011 ◽  
Vol 70 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Beat Meier ◽  
Anja König ◽  
Samuel Parak ◽  
Katharina Henke
Keyword(s):  
Memory Trace ◽  
Thought Suppression ◽  
Test Phase ◽  
Indirect Test ◽  
Final Test ◽  
Test Experiment ◽  
And Control ◽  
Cue Words ◽  
The Impact

This study investigates the impact of thought suppression over a 1-week interval. In two experiments with 80 university students each, we used the think/no-think paradigm in which participants initially learn a list of word pairs (cue-target associations). Then they were presented with some of the cue words again and should either respond with the target word or avoid thinking about it. In the final test phase, their memory for the initially learned cue-target pairs was tested. In Experiment 1, type of memory test was manipulated (i.e., direct vs. indirect). In Experiment 2, type of no-think instructions was manipulated (i.e., suppress vs. substitute). Overall, our results showed poorer memory for no-think and control items compared to think items across all experiments and conditions. Critically, however, more no-think than control items were remembered after the 1-week interval in the direct, but not in the indirect test (Experiment 1) and with thought suppression, but not thought substitution instructions (Experiment 2). We suggest that during thought suppression a brief reactivation of the learned association may lead to reconsolidation of the memory trace and hence to better retrieval of suppressed than control items in the long term.

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