Consulta: creatorFacets:"Smith,   Elwin G."
Registros recuperados: 14
Data/hora: 02/06/2024 19:02:58

SOIL QUALITY ATTRIBUTE TIME PATHS:  OPTIMAL LEVELS AND VALUES
Provedor de dados: 31
Autores: Smith,   Elwin G.; Lerohl,   Mel L.; Messele,   Teklay; Janzen,   H. Henry.
We develop a dynamic soil quality model to evaluate optimal cropping systems in the northern Great Plains. Modeling soil quality attributes is feasible, and attribute model results apply to a wide range of soils. A crop production system with continuous spring wheat and direct planting is the most profitable system. This system has low soil erosion and high quality attributes, indicating the benefits of increased soil quality exceed the higher maintenance costs. On-site value of additional soil organic carbon (OC) ranges from $1 to $4/ton OC/hectare/year. These values for soil OC impact the optimum tillage practice, but not the crop rotation.
Tipo: Journal Article
Palavras-chave: Crop Production/Industries.
Ano: 2000
URL: http://purl.umn.edu/30827

Prairie Crop Diversification
Provedor de dados: 31
Autores: Smith,   Elwin G.; Young,   Douglas L.; Zentner,   Robert P.
The Canadian prairies traditionally have been dominated by spring wheat production. Crop diversification is now being advocated to enhance farm-level risk management, ecological benefits, nutrient cycling, and pest and disease control, and to reduce the farm economy’s reliance on income from a single crop. There has always been interest in diversifying away from wheat, but until recently, economically feasible alternatives have been limited, and government policies may have constrained the shift to other crops. Knowing the impact of prices and policies on crop diversification is essential to understanding producer response and to determining strategies to enhance cropping diversity.
Tipo: Journal Article
Palavras-chave: Marketing.
Ano: 2001
URL: http://purl.umn.edu/45695

OPTIMUM SOIL QUALITY ATTRIBUTE LEVELS AND VALUES
Provedor de dados: 31
Autores: Smith,   Elwin G.; Lerohl,   Mel L.; Messele,   Teklay.
We develop a dynamic optimal cropping systems model for the northern Great Plains, taking into account the impact of the system on soil quality attributes organic and inorganic carbon.  Continuous wheat and direct planting is the most profitable system under most economic conditions.  This system has low soil erosion and results in high soil quality.
Tipo: Conference Paper or Presentation
Palavras-chave: Land Economics/Use.
Ano: 1999
URL: http://purl.umn.edu/35697

The Sweet Smell of Subsidies Revisited
Provedor de dados: 31
Autores: Young,   Douglas L.; Smith,   Elwin G.; Smith,   Anne M.
Tipo: Journal Article
Palavras-chave: Agricultural and Food Policy.
Ano: 2005
URL: http://purl.umn.edu/93506

RISK EFFICIENCY OF ALTERNATE CANOLA MANAGEMENT DECISIONS
Provedor de dados: 31
Autores: Upadhyay,   Bharat Mani; Smith,   Elwin G.; Clayton,   George; Harker,   Neil.
This study evaluates profitability and risk associated with eighteen different management decisions for canola production in Alberta. Expected payoff from cultivar selection outweighs the payoff from time of seeding and from time of weed control. Expected payoff was higher from hybrid compared to inbred cultivars. Early spring seeding was more profitable than fall or mid-May seeding. A typical decision in the sample showed positive and significant upper limit risk-expected return tradeoffs. The generalized stochastic dominance analysis revealed that early spring seeding was dominant over fall and mid-May seeding across all risk averse and risk neutral farmers. Weed control at the six-leaf stage was risk efficient for a risk averter. A risk neutral farmer...
Tipo: Conference Paper or Presentation
Palavras-chave: Risk and Uncertainty.
Ano: 2004
URL: http://purl.umn.edu/34193

WISE - A Multidisciplinary Water Research Institute in Southern Alberta
Provedor de dados: 31
Autores: Smith,   Elwin G.; Klein,   Kurt K.
Water is one of many economic drivers for southern Alberta. Industries such as intensive livestock operations and food processing depend on irrigation infrastructure for water. Lethbridge is the location most often associated with irrigation, though much of the irrigation is actually located east (Taber to Medicine Hat) and northeast (Strathmore to Brooks) of Lethbridge. Multidisciplinary research projects are needed to analyze and document the stream flow requirements of aquatic and riparian ecosystems; such research would allow the development of river regulation strategies that preserve these ecosystems. Research on water quality and water quantity is of high priority. How do dams affect downstream ecosystems in the South Saskatchewan River basin,...
Tipo: Journal Article
Palavras-chave: Resource /Energy Economics and Policy.
Ano: 2004
URL: http://purl.umn.edu/45983

An Innovative Approach for Modeling Crop Yield Response to Fertilizer Nutrients
Provedor de dados: 31
Autores: Upadhyay,   Bharat Mani; Smith,   Elwin G.; Favret,   M. Lucila.
Fertilizer recommendations seldom account for agro-climatic conditions, which are important factors that determine the response to fertilizer and the optimal rate of fertilizer. The nitrogen fertilizer response to open pollinated and hybrid canola types will also impact optimal nitrogen rates. This study used quantile regression to model canola yield response to nitrogen fertilizer. Quantile regression can apply different weights to the residuals, facilitating a response estimation where the agro-climatic conditions are not limiting and the yield response is due to the variable of interest. The economically optimal levels of fertilizers were calculated using the proposed and the conventional least squares procedures of the two canola types in western...
Tipo: Conference Paper or Presentation
Palavras-chave: Crop Production/Industries.
Ano: 2006
URL: http://purl.umn.edu/34183

EVALUATING A PRECISION AGRICULTURE HERBICIDE DECISION MODEL FOR WINTER WHEAT
Provedor de dados: 31
Autores: Young,   Douglas L.; Kwon,   Tae-Jin; Smith,   Elwin G.; Young,   F.L.
Replaced with revised version of paper 08/02.
Tipo: Conference Paper or Presentation
Palavras-chave: Crop Production/Industries.
Ano: 2002
URL: http://purl.umn.edu/19819

Greenhouse Gas Mitigation on Diversified Farms
Provedor de dados: 31
Autores: Smith,   Elwin G.; Upadhyay,   Bharat Mani.
Agriculture can potentially contribute to Canada meeting its commitment to reduce net greenhouse gas (GHG) emissions under the Kyoto protocol. A representative crop - livestock feeding farm on the Canadian prairies is used to estimate the cost of net GHG abatement, taking into account CO2 equivalent emissions and carbon sequestration. Optimal cropping systems use direct seeding and continuous cropping, production systems that have lower net GHG emissions. Livestock feeding uses rations with high energy concentration (grain based) because they are more profitable and also produce less methane per animal than forage based diets. Reducing tillage is the least costly means of lowering  net emissions ($20/t CO2 eq.), followed by reducing cattle feeding ($32/t...
Tipo: Conference Paper or Presentation
Palavras-chave: Environmental Economics and Policy.
Ano: 2005
URL: http://purl.umn.edu/34165

Modeling Crop Yield Distributions from Small Samples
Provedor de dados: 31
Autores: Upadhyay,   Bharat Mani; Smith,   Elwin G.
Accurately modeling crop yield distributions is important for estimation of crop insurance premiums and farm risk-management decisions. A major challenge in the modeling has been due to small sample size. This study evaluated potentials of L-moments, a recent concept in mathematical statistics, in modeling crop yield distribution. Five candidate distributions were ranked for describing the wheat yields. The selected distribution was robust for small sample and was invariant to de-trending. The result was consistent with that from the maximum likelihood and goodness-of-fit method.
Tipo: Conference Paper or Presentation
Palavras-chave: Crop Production/Industries.
Ano: 2005
URL: http://purl.umn.edu/34161

AGGREGATION ISSUES IN PEST CONTROL ECONOMICS: A BIOECONOMIC APPROACH
Provedor de dados: 31
Autores: Young,   Douglas L.; Smith,   Elwin G.; Kwon,   Tae-Jin.
Previous research has defined “aggregate pesticide expenditures” as the control variable; however, virtually all managerial recommendations and environmental restrictions target specific pesticides, rates, and crops. A bioeconomic approach considering particular pesticides on specific pests and crops is recommended for managerial-policy applications and testing for increasing returns. Exponential weed control and seven popular yield damage functional forms were estimated for a bioeconomic weed control model for winter wheat in Washington. Concavity with respect to herbicide rate was observed for most popular damage functions at normal weed densities and manufacturers’ label rates, but convexity existed outside these ranges and should be checked.
Tipo: Conference Paper or Presentation
Palavras-chave: Bioeconomic; Data aggregation; Herbicide; Increasing returns; Pest control; Pesticide; Weed; Crop Production/Industries.
Ano: 2000
URL: http://purl.umn.edu/36448

CROPPING DIVERSITY AND FARM PROGRAMS
Provedor de dados: 31
Autores: Smith,   Elwin G.; Young,   Douglas L.
Cropping diversity along the United States - Canada border of the Great Plains has not been dominated by either country. U.S. wheat policies impacted diversity in both countries through price and in the U.S. by acreage reduction programs. In the 1990s, cropping diversity increased in Canada and declined in the U.S. Since the 1996 U.S. Farm Bill, cropping diversity has increased in the U.S.
Tipo: Conference Paper or Presentation
Palavras-chave: Agricultural and Food Policy; Crop Production/Industries.
Ano: 2000
URL: http://purl.umn.edu/36505

An Investment Analysis Approach to Examining Bio-Control of Invasive Weeds
Provedor de dados: 31
Autores: Smith,   Elwin G.; Young,   Douglas L.
Invasive weeds are a large problem on large tracts of rangeland in North America. Biological methods of control have been instituted, but many information gaps remain. An investment model approach is used to demonstrate some of the potentially key pieces of biological data that are required for an analysis. This model is applied to the control of leafy spurge on rangeland. The results of control are very dependent on the rate of spread and control by the biological control agent, the initial density of the weed, and the recovery of the forage (grass) after the weed has been controlled. Benefits of control are relatively low, as is the cost of the biological control practice. It takes several years before net benefits of the control practice are positive.
Tipo: Conference Paper or Presentation
Palavras-chave: Land Economics/Use.
Ano: 2005
URL: http://purl.umn.edu/36286

Factors Influencing Wheat Yield and Variability: Evidence from Manitoba, Canada
Provedor de dados: 31
Autores: Carew,   Richard; Smith,   Elwin G.; Grant,   Cynthia.
Production functions to explain regional wheat yields have not been studied extensively in the Canadian prairies. The objective of this study is to employ a Just-Pope production function to examine the relationship between fertilizer inputs, soil quality, biodiversity indicators, cultivars qualifying for Plant Breeders’ Rights (PBR), and climatic conditions on the mean and variance of spring wheat yields. Using regional-level wheat data from Manitoba, Canada, model results show nitrogen fertilizer, temporal diversity, and PBR wheat cultivars are associated with increased yield variance. Mean wheat yield is reduced by the proportion of land in wheat, the interaction of growing temperature and precipitation, and spatial diversity. By contrast, higher soil...
Tipo: Journal Article
Palavras-chave: Climate; Fertilizer; Manitoba; Plant Breeders’ Rights; Production risk; Wheat; Yield; Agribusiness; Crop Production/Industries; Farm Management; Land Economics/Use; Productivity Analysis; Risk and Uncertainty; O18; Q16.
Ano: 2009
URL: http://purl.umn.edu/56649