13 research outputs found
B811: Field Appraisal of Resource Management Systems Farms Crop Yield and Quality Relationships with Soil Erosion - 1982
This document presents the objectives and third-year results of the Field Appraisal of Resource Management Systems (FARMS) study. The principal objectives of FARMS were to study the relationship of crop yields to predicted soil erosion and to simulate the economics of this relationship. Crop management, soils, conservation practices and management, crop yields, soil chemistry, and sociological data were collected. The data analyzed in preparing this report are from the 800 plots sampled in 1982. This report presents statistics for rill and sheet soil erosion, which is estimated by the Universal Soil Loss Equation (USLE) and assumed to represent a long term rather than short term effect. The report also presents summary statistics for each of the factors in the USLE: for potato yields and quality, for yields of four other field crops, and for soil nutrient analyses.https://digitalcommons.library.umaine.edu/aes_bulletin/1107/thumbnail.jp
B805: Field Appraisal of Resource Management Systems: Crop Yield and Quality Relationships with Soil Erosion—1981
This document presents objectives and results of the Field Appraisal of Resource Management Systems (FARMS) study\u27S second year. The principal objectives of FARMS were to study the relationship of crop yields to soil erosion and to simulate the economic nature of this relationship. Crop management, soils, conservation practices and management, crop yields, soil chemistry, and sociological data were collected from 800 plots in 1981. This report presents statistics for rill and sheet soil erosion, which are estimated by the Universal Soil Loss Equation (USLE) and assumed to represent a long-term rather than short-term effect. The report also presents summary statistics for each of the factors in the USLE: for potato yields and quality, for yields of six other field crops, and for soil nutrient analyses. No general response of potato yield and quality to predicted soil erosion was found. However, individual potato varieties responded differently to predicted soil erosion. Potato yields and specific gravity were found to be significantly related to the Cover and Management factor (C). Potato yield was found to decrease as intensity of potato production increased in the rotation period. Potato yields were significantly reduced when the previous crop was potatoes in comparison to grain or hay.https://digitalcommons.library.umaine.edu/aes_bulletin/1056/thumbnail.jp
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Deconstruction of Holistic Rubrics into Analytic Rubrics for Large-Scale Assessments of Students’ Reasoning of Complex Science Concepts
Constructed responses can be used to assess the complexity of student thinking and can be evaluated using rubrics. The two most typical rubric types used are holistic and analytic. Holistic rubrics may be difficult to use with expert-level reasoning that has additive or overlapping language. In an attempt to unpack complexity in holistic rubrics at a large scale, we have developed a systematic approach called deconstruction. We define deconstruction as the process of converting a holistic rubric into defining individual conceptual components that can be used for analytic rubric development and application. These individual components can then be recombined into the holistic score which keeps true to the holistic rubric purpose, while maximizing the benefits and minimizing the shortcomings of each rubric type. This paper outlines the deconstruction process and presents a case study that shows defined concept definitions for a hierarchical holistic rubric developed for an undergraduate physiology-content reasoning context. These methods can be used as one way for assessment developers to unpack complex student reasoning, which may ultimately improve reliability and validation of assessments that are targeted at uncovering large-scale complex scientific reasoning. Accessed 398 times on https://pareonline.net from September 05, 2019 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right
Biased feedback in spatial recall yields a violation of delta rule learning
This study investigates whether inductive processes influencing spatial memory performance generalize to supervised learning scenarios with differential feedback. After providing a location memory response in a spatial recall task, participants received visual feedback showing the target location. In critical blocks, feedback was systematically biased either 4 degrees toward the vertical axis (toward condition) or 4 degrees farther away from the vertical axis (away condition). Results showed that the weaker teaching signal (i.e., a smaller difference between the remembered location and the feedback location) produced a stronger experience-dependent change over blocks in the away condition than in the toward condition. This violates delta rule learning. Subsequent simulations of the dynamic field theory of spatial cognition provide a theoretically unified account of these results
Location memory biases reveal the challenges of coordinating visual and kinesthetic reference frames
Five experiments explored the influence of visual and kinesthetic/proprioceptive reference frames on location memory. Experiments 1 and 2 compared visual and kinesthetic reference frames in a memory task using visually-specified locations and a visually-guided response. When the environment was visible, results replicated previous findings of biases away from the midline symmetry axis of the task space, with stability for targets aligned with this axis. When the environment was not visible, results showed some evidence of bias away from a kinesthetically-specified midline (trunk anterior–posterior [a–p] axis), but there was little evidence of stability when targets were aligned with body midline. This lack of stability may reflect the challenges of coordinating visual and kinesthetic information in the absence of an environmental reference frame. Thus, Experiments 3–5 examined kinesthetic guidance of hand movement to kinesthetically-defined targets. Performance in these experiments was generally accurate with no evidence of consistent biases away from the trunk a–p axis. We discuss these results in the context of the challenges of coordinating reference frames within versus between multiple sensori-motor systems