11,107 research outputs found
IMPACTS OF NEW AGRICULTURAL TECHNOLOGIES ON RURAL MALIAN HOUSEHOLDS
A need in Sahelian agriculture is to transform from traditional farming to more modern systems. This paper presents a safety-first type of risk programming model, using complementary programming, to assess the impacts of new agricultural technology. Model results indicate that some new technologies are economically attractive to Malian households.Research and Development/Tech Change/Emerging Technologies,
Land Degradation in the Sahel: An Application of Biophysical Modeling in the Optimal Control Setting
Low-input farming practices in many parts of the developing world have pushed cultivation onto marginal lands. Sustainability of already fragile ecosystems is threatened. Farmers place a high priority on satisfying subsistence food needs with on-farm production. Population pressure is high throughout much of Sub-Saharan Africa. Farmers in those regions are challenged by the need to put continually more food on their table over the coming years. An optimal control model was developed to investigate alternative farming practices within this setting. Namely, whether farmers would choose continued land expansion of if they would adopt crop intensive practices. The model included an environmental subcomponent to estimate the degradation costs from continued expansion onto marginal areas. The modeling activities from the Sahel of West African reinforce farmers' observed propensity to clear new land in lieu of crop intensification. Model activities suggest an important role for crop intensification under adequate policy conditions as well as the need to introduce new technology before degradation erodes its potential.Land Economics/Use,
The 2004 Niger Food Crisis: What Role Can Price Discovery Play in Famine Early Warning Systems?
The 2005 food crisis centered in Niger received worldwide attention and extensive media coverage. Crops suffered from poor rainfall and were plagued by locusts throughout the growing season. Malnutrition flourished with the sudden disruption in food supplies. One-fifth of Niger's children suffered from moderate to severe forms of malnutrition by the summer of 2005. In an era of increased awareness and the introduction of famine early warning systems, the development community was left wondering why they were for the most part caught off guard by the food crisis. This paper tests whether market prices and price discovery could have played an active role in detecting the food crisis. Directed acyclic graphs are used to test whether price discovery mechanisms within Niger's millet markets were ahead of the early warning systems. Results suggest that as early as October 2005 markets in Arlit and the Dosso province had price anomalies that appeared to begin signaling the upcoming food crisis. This market based discovery came about two months earlier than the warnings issued by the regional early warning networks.Food Security and Poverty,
Effect of Corn Price on Profitability of Control Vs Phytase Enhanced Diet of Hogs
Economic Simulation model (SIMETAR) was used to investigate the effect of future corn price on profitability of control and phytase enhanced diet of hogs. The completed simulation model was used to estimate probability distribution for control vs lower excretion diet profitability under different corn prices. Data used was collected from recent field trials in Oklahoma that tested the effect of phytase enhanced diets on reducing phosphorus emission. The results showed that as the market price of corn increases control diet will be more profitable than phytase enhanced diet, given the cost of other remaining feed ingredient is constant for both the diets.profitability, SIMETAR, control diet, phytase enhanced diet, swine, Production Economics,
The Cost of Coexistence between Bt Maize and Open Pollinated Maize Varieties in Lowland Coastal Kenya
Kenya is currently in the process of introducing genetically modified maize (Bt maize). A major concern is that the Bt gene might cross into local varieties through cross pollination. Current regulatory strategies to ensure coexistence of the two cropping systems at the farm level rely on spatial isolation measures-separation distances and/or buffer zones. However, the interaction of practical measures and costs of spatial isolation with the farmer’s economic incentive to plant a Bt maize crop have not been studied in Kenya. The purpose of this study was to analyze the technical and economic feasibility of the implementation of spatial coexistence measures. Using spatial geo-referenced data from the actual agricultural landscape in lowland coastal Kenya, the study finds that flexible separation distances hold the possibility of ensuring coexistence in the region, but will be difficult to implement. Rigid buffer strips on the other hand are not consistent with the producers’ economic incentive to plant a Bt maize crop.Coexistence, Regulatory, Spatial, Agro-ecological zone, GM crops, Resource /Energy Economics and Policy,
Conventional Tillage versus No-till: Characteristics of Producers and Farms
A survey of Oklahoma farmers was conducted to determine characteristics of farms across three tillage categories: conventional tillage exclusively; no-till exclusively; other (combination of systems). The seven percent that use no-till exclusively crop more acres, rent more acres, and use more crop rotations than farms that use conventional tillage exclusively.no-till, conventional tillage, survey, farm machinery, farm size, wheat, perceptions, Crop Production/Industries, Farm Management, Q10, Q12,
Measuring the LISA test mass magnetic proprieties with a torsion pendulum
Achieving the low frequency LISA sensitivity requires that the test masses
acting as the interferometer end mirrors are free-falling with an unprecedented
small degree of deviation. Magnetic disturbances, originating in the
interaction of the test mass with the environmental magnetic field, can
significantly deteriorate the LISA performance and can be parameterized through
the test mass remnant dipole moment and the magnetic susceptibility
. While the LISA test flight precursor LTP will investigate these effects
during the preliminary phases of the mission, the very stringent requirements
on the test mass magnetic cleanliness make ground-based characterization of its
magnetic proprieties paramount. We propose a torsion pendulum technique to
accurately measure on ground the magnetic proprieties of the LISA/LTP test
masses.Comment: 6 pages, 3 figure
A robust data cleaning procedure for eddy covariance flux measurements
Abstract. The sources of systematic error responsible for introducing significant biases in the eddy covariance (EC) flux computation are manifold, and their correct identification is made difficult by the lack of reference values, by the complex stochastic dynamics, and by the high level of noise characterizing raw data. This work contributes to overcoming such challenges by introducing an innovative strategy for EC data cleaning.
The proposed strategy includes a set of tests aimed at detecting the presence of specific sources of systematic error, as well as an outlier detection procedure aimed at identifying aberrant flux values. Results from tests and outlier detection are integrated in such a way as to leave a large degree of flexibility in the choice of tests and of test threshold values, ensuring scalability of the whole process. The selection of best performing tests was carried out by means of Monte Carlo experiments, whereas the impact on real data was evaluated on data distributed by the Integrated Carbon Observation System (ICOS) research infrastructure.
Results evidenced that the proposed procedure leads to an effective cleaning of EC flux data, avoiding the use of subjective criteria in the decision rule that specifies whether to retain or reject flux data of dubious quality.
We expect that the proposed data cleaning procedure can serve as a basis towards a unified quality control strategy for EC datasets, in particular in centralized data processing pipelines where the use of robust and automated routines ensuring results reproducibility constitutes an essential prerequisite
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