Irrigation scheduling is critical as it affects both fruit yield and composition. We examined the... more Irrigation scheduling is critical as it affects both fruit yield and composition. We examined the poten- tial to use field-measured hyperspectral remote sensing data (reflectance and transmission over the 350-2500 nm wavelength region) to estimate leaf water content, equivalent water thickness (EWT), and leaf water potential (Ψ) in a commercial vineyard of Vitis vinifera cv. Pinot noir. The data allowed
Actualmente, la producción vitivinícola se está viendo afectada por diversos factores atribuibles... more Actualmente, la producción vitivinícola se está viendo afectada por diversos factores atribuibles al cambio global, como la introducción de nuevas variedades de cultivo, tanto foráneas como ancestrales. El Priorato es una buena región para el análisis y valoración del nivel de impacto. http://www.acenologia.com/ciencia95_2.htm
While the use of no-tillage and improved fertilizer management are proposed as effective ways to ... more While the use of no-tillage and improved fertilizer management are proposed as effective ways to enhance corn yield and reduce greenhouse gas emission, their effects remain controversial and the related influencing factors are not well understood. We conducted a field experiment to study the responses of corn yield and N2O emission to various management practices in middle Tennessee. The management practices include no-tillage + regular applications of urea ammonium nitrate (NT-urea); no-tillage + regular applications of urea + denitrification inhibitor (NT-inhibitor); no-tillage + regular applications of urea + biochar (NT-biochar); no-tillage + 20% applications of urea + chicken litter (NT-litter), no-tillage + split applications of urea (NT-split); and conventional tillage + regular applications of urea as a control (CT-urea). Fertilizer equivalent to 217 kg N ha−1 was applied to each of the experimental plots. The experiment used a randomized complete block design with six repli...
ABSTRACT Currently, the application of fertilizer and water in orchard crops follows largely stan... more ABSTRACT Currently, the application of fertilizer and water in orchard crops follows largely standardized practices with limited consideration of temporal, climatic and crop variability. This approach constrains our ability to improve management, results in loss of potential income and causes negative environmental impact. We strive to address this issue by integrating 1) new approaches to determine crop demand with spatial and temporal accuracy, with 2) advanced methods of estimating current crop status and performance with 3) the development a new site specific orchard management platform. In this poster (#1 of 2), we discuss integrated approaches to define real time crop demand' for water and nutrients with high spatial and temporal demand for water and nitrogen by deciduous perennial crops. In a partner poster we present advanced methods for crop status' determination. A series of 8 research sites were established in 2008 throughout California, New Mexico and Texas in Almond, Pistachio and Pecan. Fertilizer rate trials and nutrient monitoring (all essential elements) in plant, soil, and crop are being used to construct nutrient budgets with a high degree of spatial and temporal specificity. Water demand is being estimated with a number of redundant models and with real time monitoring of plant, soil and atmospheric parameters. Yield prediction and nutrient and water demand models are under development through the integration of multi-year yield monitoring in a large number (>1,500) individual trees. Fertilizer rate trials and irrigation treatments have been established to develop response curves and interaction required for model refinement. Preliminary results will be presented on the following: Whole tree nutrient budgeting Temporal pattern of nutrient uptake annually Within tree nutrient partitioning Yield estimation modeling Comparative analysis of soil, plant and model based determination of water demand
3 CT = fn δ 13 Cn + fo δ 13 Co), where CT. is the δ 13 C label of total soil respired CO2 and fn ... more 3 CT = fn δ 13 Cn + fo δ 13 Co), where CT. is the δ 13 C label of total soil respired CO2 and fn and fo are the fractions derived from the more labile (13C labeled) and recalcitrant pools respectively. Rhizosphere respiration was approximately one fifth of above ground respiration in both years. In 2004 moisture levels were low as a consequence of spring drought. Labile C sources were retained in soils throughout the summer in 2004, being strongly oxidized with the onset of autumn precipitation. In contrast to 2004, in 2005 precipitation in April and May greatly increased both soil moisture and 13C loss from both the more labile and recalcitrant pools in both the 2004 labeled and 2005 labeled systems. The quantity of carbon oxidized and emitted by soil respiration following tillage in 2005, when moisture contents were high, was prolonged and challenges previous assumptions concerning the timing and intensity of microbial activity following tillage disturbance. 13 C pools retained in...
Irrigation scheduling is critical as it affects both fruit yield and composition. We examined the... more Irrigation scheduling is critical as it affects both fruit yield and composition. We examined the poten- tial to use field-measured hyperspectral remote sensing data (reflectance and transmission over the 350-2500 nm wavelength region) to estimate leaf water content, equivalent water thickness (EWT), and leaf water potential (Ψ) in a commercial vineyard of Vitis vinifera cv. Pinot noir. The data allowed
Actualmente, la producción vitivinícola se está viendo afectada por diversos factores atribuibles... more Actualmente, la producción vitivinícola se está viendo afectada por diversos factores atribuibles al cambio global, como la introducción de nuevas variedades de cultivo, tanto foráneas como ancestrales. El Priorato es una buena región para el análisis y valoración del nivel de impacto. http://www.acenologia.com/ciencia95_2.htm
While the use of no-tillage and improved fertilizer management are proposed as effective ways to ... more While the use of no-tillage and improved fertilizer management are proposed as effective ways to enhance corn yield and reduce greenhouse gas emission, their effects remain controversial and the related influencing factors are not well understood. We conducted a field experiment to study the responses of corn yield and N2O emission to various management practices in middle Tennessee. The management practices include no-tillage + regular applications of urea ammonium nitrate (NT-urea); no-tillage + regular applications of urea + denitrification inhibitor (NT-inhibitor); no-tillage + regular applications of urea + biochar (NT-biochar); no-tillage + 20% applications of urea + chicken litter (NT-litter), no-tillage + split applications of urea (NT-split); and conventional tillage + regular applications of urea as a control (CT-urea). Fertilizer equivalent to 217 kg N ha−1 was applied to each of the experimental plots. The experiment used a randomized complete block design with six repli...
ABSTRACT Currently, the application of fertilizer and water in orchard crops follows largely stan... more ABSTRACT Currently, the application of fertilizer and water in orchard crops follows largely standardized practices with limited consideration of temporal, climatic and crop variability. This approach constrains our ability to improve management, results in loss of potential income and causes negative environmental impact. We strive to address this issue by integrating 1) new approaches to determine crop demand with spatial and temporal accuracy, with 2) advanced methods of estimating current crop status and performance with 3) the development a new site specific orchard management platform. In this poster (#1 of 2), we discuss integrated approaches to define real time crop demand' for water and nutrients with high spatial and temporal demand for water and nitrogen by deciduous perennial crops. In a partner poster we present advanced methods for crop status' determination. A series of 8 research sites were established in 2008 throughout California, New Mexico and Texas in Almond, Pistachio and Pecan. Fertilizer rate trials and nutrient monitoring (all essential elements) in plant, soil, and crop are being used to construct nutrient budgets with a high degree of spatial and temporal specificity. Water demand is being estimated with a number of redundant models and with real time monitoring of plant, soil and atmospheric parameters. Yield prediction and nutrient and water demand models are under development through the integration of multi-year yield monitoring in a large number (>1,500) individual trees. Fertilizer rate trials and irrigation treatments have been established to develop response curves and interaction required for model refinement. Preliminary results will be presented on the following: Whole tree nutrient budgeting Temporal pattern of nutrient uptake annually Within tree nutrient partitioning Yield estimation modeling Comparative analysis of soil, plant and model based determination of water demand
3 CT = fn δ 13 Cn + fo δ 13 Co), where CT. is the δ 13 C label of total soil respired CO2 and fn ... more 3 CT = fn δ 13 Cn + fo δ 13 Co), where CT. is the δ 13 C label of total soil respired CO2 and fn and fo are the fractions derived from the more labile (13C labeled) and recalcitrant pools respectively. Rhizosphere respiration was approximately one fifth of above ground respiration in both years. In 2004 moisture levels were low as a consequence of spring drought. Labile C sources were retained in soils throughout the summer in 2004, being strongly oxidized with the onset of autumn precipitation. In contrast to 2004, in 2005 precipitation in April and May greatly increased both soil moisture and 13C loss from both the more labile and recalcitrant pools in both the 2004 labeled and 2005 labeled systems. The quantity of carbon oxidized and emitted by soil respiration following tillage in 2005, when moisture contents were high, was prolonged and challenges previous assumptions concerning the timing and intensity of microbial activity following tillage disturbance. 13 C pools retained in...
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