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ABSTRACT Software for an automatic weather data collection and processing software was developed based around a computer bulletin board (OPUS). At night, an external event timer stops the bulletin board, executes a series of EXE files... more
ABSTRACT Software for an automatic weather data collection and processing software was developed based around a computer bulletin board (OPUS). At night, an external event timer stops the bulletin board, executes a series of EXE files that interrogate climate stations, processes and writes the data to files.OPUS makes meteorological data readily available in electronic form. Users can download data, convert data to select formats and then download the processed data or run external programs that use the climatic data.
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Satellite-received radiances and auxiliary ground-based information are routinely used to estimate the evapotranspiration rate (ET, or LE as a latent heat energy flux density) on landscape elements. Many methods compute LE as a residual,... more
Satellite-received radiances and auxiliary ground-based information are routinely used to estimate the evapotranspiration rate (ET, or LE as a latent heat energy flux density) on landscape elements. Many methods compute LE as a residual, computing the terms Rn, G, and H in the full energy-balance equation, S = Rn - G ¬ H - LE, where S is surface (canopy) heat storage (often assumed near zero), Rn is net radiation, G is heat flux into the (soil) surface, and H is the sensible heat flux. Computation of H is prone to errors in obtaining accurate radiometric temperatures, TR, of the surface and in relating TR to the true kinetic temperature of the surface heat source. The Surface Energy BAlance Land (SEBAL) method avoids the offset errors by introducing an assumption of a linear relation of TR to the surface-to-air temperature difference. This assumption, and several others, can introduce distinct errors and operational problems, which will be discussed, along with several improvements under development. The latter include direct regression solutions for LE, correcting for advection of energy and for the lapse rate of the surface (not air) temperature, and the use of auxiliary radiance-based information on vegetation water stress. Also to be discussed are potential applications of enhanced ET methods to estimate hydrologic redistributions (runon, runoff), the consequent spatial patterning of vegetation, and the implications of both for ecological studies (equilibrium canopy development, long-term acclimation of stomatal control) and ecosystem management (estimating forest water stress and its relations to stand density, forest thinning exercises, and hazards of fire and insect outbreaks).
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Remote sensing evapotranspiration (ET) models are important for forest, phreatophyte, rangeland, and agricultural water and pest management. However, most remote sensing ET models are not available in an Internet-based operational mode.... more
Remote sensing evapotranspiration (ET) models are important for forest, phreatophyte, rangeland, and agricultural water and pest management. However, most remote sensing ET models are not available in an Internet-based operational mode. Manually downloading satellite and weather data and processing this data is complicated and time-consuming, requiring as much as 2-6 hrs per satellite scene. If the ET algorithm is going to be used by the scientific community or management agencies and farmers, it is imperative that the computer processing be automated and user-friendly; the user should be able to input the dates and locations of interest and have the model output the ET results (map and ACSII data file). The objective of our research was to test the hypothesis that remote sensing algorithms that calculate daily ET based on energy balance could be automated. An Internet-based ET model using MODIS, local weather station, and forecast data was developed. The automated calculated daily ET was compared to measured eddy-covariance ET under both stressed and non-stressed conditions.
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ABSTRACT Land application of wastewater conserves fresh water and recycles nutrients, but little is known of its impacts on arid and semiarid landscapes. Lagoon treated saline−sodic industrial effluent was applied from 2002–2005 to a... more
ABSTRACT Land application of wastewater conserves fresh water and recycles nutrients, but little is known of its impacts on arid and semiarid landscapes. Lagoon treated saline−sodic industrial effluent was applied from 2002–2005 to a 0.4-ha Chihuahuan Desert shrubland to assess the deposition and recovery of effluent components and changes in soil quality vis-à-vis a non-irrigated area. Effluent irrigation supplied 26% of the average annual nonstressed evapotranspiration (ET) of the native shrubs [Larrea tridentata (DC.) Coville and Prosopis glandulosa Torr. var. glandulosa], and increased both soil stress factors (sodicity, salinity, and pH) and soil fertility (N, P, and K). After 3 yr, the soil saturation extract electrical conductivity (ECe) reached as high as 6.1 dS m−1 and Cl− 76 molc m−3 at 105 cm depth under irrigated L. tridentata. After 4 yr, saturation extract sodium adsorption ratio (SARe) reached 25–35 at 7.5 cm under the irrigated shrubs and intershrub spaces. There were 27 Mg ha−1 of cumulative ionic deposits to the site comprised mostly of Na+, Cl−, and CaCO3 equivalent alkalinity, with soil analysis recovering most of the deposits (>57%) except for K+ and Na+ (8% to 13%). Subsurface leaching of and P was detected within the upper 1 m soil depth after 4 yr, and a high downward mobility of Cl− revealed the potential for deeper leaching at higher N loading rates. While long-term effects on the natural vegetation are unknown, results contribute to a limited scientific database for sustainable wastewater land application in semiarid regions.
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Research Interests:
Research Interests:
Research Interests:
Research Interests:
ABSTRACT Rising fertilizer costs and diminishing water resources, have made improved efficiency of water and nitrogen management a top research and extension priority for the deciduous crop industries. Pecan is among the deciduous crops... more
ABSTRACT Rising fertilizer costs and diminishing water resources, have made improved efficiency of water and nitrogen management a top research and extension priority for the deciduous crop industries. Pecan is among the deciduous crops and it uses the most amount of water among all the tree crops. Currently, there is no model to simulate pecan tree growth under water and nitrogen stress that has been calibrated and evaluated by experimental data. In this study, a pecan growth model was developed that contains a nitrogen stress function and a water stress function. The nitrogen function limits tree growth based on leaf nitrogen concentration. Leaf concentration was calculated by nitrogen concentration at the root zone and nitrogen distribution to the tree components. At the same time, evapotranspiration was reduced by nitrogen stress and interacts with the water stress function. The stress functions and their interactions were calibrated by results from a physiological mechanistic model and experimental data. The pecan tree growth model was evaluated by experimental data. The evaluation shows that the water stress function is reasonably well, while it may overestimate the nitrogen uptake. More field experiments need to be conducted to calibrate the related parameters.
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Research Interests:
The purity of product from agricultural cleaners (such as chile, cotton, bean, wheat and other crop cleaners) is needed to be measured under various conditions in order to adjust and optimize the machine at the design and improvement... more
The purity of product from agricultural cleaners (such as chile, cotton, bean, wheat and other crop cleaners) is needed to be measured under various conditions in order to adjust and optimize the machine at the design and improvement stages. The traditional weight-based method of measuring purity is time consuming, and requires much labor. In this study, we used image analysis to measure percent crop cover for the product output to infer the purity. Chile cleaner was used as one example machine to compare between Photoshop© and Arcview© software for the analysis of fresh and dry harvest pictures. The data collection process is more reproducible and less labor and time consuming than the traditional technique. Both software packages provided accurate estimations of purity for both fresh and dry harvest pictures. Photoshop© had better accuracy than Arcview© (mean error ratio of 0.016 vs. 0.081 for fresh harvest; and 0.035 vs. 0.114 for dry harvest). Citation: Wang J, Eaton F E, Sammis...
Research Interests: Image Analysis and Trash
Dust plumes in the atmosphere, generated by cotton field preparation planting and harvesting operations were measured remotely via aerosol lidar. Dust plume size, shape and movement are reported The in-plume aerosol size distributions... more
Dust plumes in the atmosphere, generated by cotton field preparation planting and harvesting operations were measured remotely via aerosol lidar. Dust plume size, shape and movement are reported The in-plume aerosol size distributions were measured with ...
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... 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
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Research Interests:
ABSTRACT Dust plumes in the atmosphere, generated by cotton field preparation and planting operations, were measured with a aerosol LIDAR in the spring of 2005. The purpose of the study was to generate plume space and time dynamics and... more
ABSTRACT Dust plumes in the atmosphere, generated by cotton field preparation and planting operations, were measured with a aerosol LIDAR in the spring of 2005. The purpose of the study was to generate plume space and time dynamics and plume concentrations for testing emission models. The measurements were made in a flood irrigation cotton field on the NMSU research farm near Las Cruces NM. The measurements were used to quantify the dynamics of plume movement and to sort the field operation generated dust from surrounding sources.
International water delivery management is a difficult issue. For example, according to the US and Mexico water delivery treaty, the US needs to deliver a certain amount of water from the Elephant Butte Reservoir (in US New Mexico state)... more
International water delivery management is a difficult issue. For example, according to the US and Mexico water delivery treaty, the US needs to deliver a certain amount of water from the Elephant Butte Reservoir (in US New Mexico state) to Mexico every year. Similarly, Mexico also needs to deliver a certain amount of water to the US each year. However,
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There is a need to create an accurate and convenient method to measure lake evaporation loss that can be used internationally. The research in this paper developed a remote sensing tool to estimate evaporation loss from reservoirs to aid... more
There is a need to create an accurate and convenient method to measure lake evaporation loss that can be used internationally. The research in this paper developed a remote sensing tool to estimate evaporation loss from reservoirs to aid international water delivery management. The model uses the energy balance principle to measure evaporation depth (mm/day). The evaporation depth has a
Research Interests:
ADDITIONAL INDEX WORDS. Carya illinoensis, flood irrigation, soil moisture, climate SUMMARY. For farmers to accurately schedule future water delivery for irrigations, a prediction method based on time-series measurements of soil moisture... more
ADDITIONAL INDEX WORDS. Carya illinoensis, flood irrigation, soil moisture, climate SUMMARY. For farmers to accurately schedule future water delivery for irrigations, a prediction method based on time-series measurements of soil moisture depletion and climate-based indicators of evaporative demand is needed. Yet, numerous reports indicate that field instruments requiring high in-season labor input are not likely to be used by farmers.
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ABSTRACT Low soil O-2 levels have been shown to limit growth in pecan [Carya illinoinensis (Wangenh.) K. Koch] seedlings and may limit yield in mature trees. To assess changes in the gas-phase O-2 concentration in a pecan orchard soil in... more
ABSTRACT Low soil O-2 levels have been shown to limit growth in pecan [Carya illinoinensis (Wangenh.) K. Koch] seedlings and may limit yield in mature trees. To assess changes in the gas-phase O-2 concentration in a pecan orchard soil in response to flood irrigations throughout a growing season, two types of O-2 sensor were field tested: a galvanic O-2 sensor and a spectometer-coupled chemical sensor (FOXY sensor). Galvanic sensors, housed in diffusion chambers, were buried at four depths and a datalogger recorded continuous voltage output. The FOXY O-2 sensor was utilized as part of a mobile O-2 detection system to field analyze gas samples withdrawn periodically from buried diffusion chambers. The FOXY sensor was found to be unstable, however, and difficult to calibrate under conditions of changing temperature and humidity. Laboratory experiments simulating submersion of the galvanic sensor indicated that voltage outputs were comparable to the range observed in the field, but the absence of diurnal concentration fluctuations, typically found in soil measurements, provided a way to discriminate between normal and aberrant output. The responsiveness of the galvanic sensor and its capability to continuously gather hourly data makes it superior to methods dependent on manual sample collection. Galvanic sensors were adequately suited for long-term in situ use in agricultural soil when housed in appropriate diffusion chambers. Higher costs, limited access to diffusion chambers during flood periods, and high variability associated with manually collected data make the FOXY mobile O-2 detection system comparatively less optimal for use in agricultural settings.
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Research Interests:
Research Interests: Earth Sciences, Boundary Layer Meteorology, Heat Transfer, Satellite remote sensing, Comparative Study, and 10 moreAtmospheric sciences, Eddy Covariance, Field Experiment, New Mexico, Atmospheric Boundary Layer, Semi Arid Region, Spatial resolution, Boundary Layer, Sensible Heat Flux, and Scintillation Counter
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ABSTRACT Land application of wastewater conserves fresh water and recycles nutrients, but little is known of its impacts on arid and semiarid landscapes. Lagoon treated saline−sodic industrial effluent was applied from 2002–2005 to a... more
ABSTRACT Land application of wastewater conserves fresh water and recycles nutrients, but little is known of its impacts on arid and semiarid landscapes. Lagoon treated saline−sodic industrial effluent was applied from 2002–2005 to a 0.4-ha Chihuahuan Desert shrubland to assess the deposition and recovery of effluent components and changes in soil quality vis-à-vis a non-irrigated area. Effluent irrigation supplied 26% of the average annual nonstressed evapotranspiration (ET) of the native shrubs [Larrea tridentata (DC.) Coville and Prosopis glandulosa Torr. var. glandulosa], and increased both soil stress factors (sodicity, salinity, and pH) and soil fertility (N, P, and K). After 3 yr, the soil saturation extract electrical conductivity (ECe) reached as high as 6.1 dS m−1 and Cl− 76 molc m−3 at 105 cm depth under irrigated L. tridentata. After 4 yr, saturation extract sodium adsorption ratio (SARe) reached 25–35 at 7.5 cm under the irrigated shrubs and intershrub spaces. There were 27 Mg ha−1 of cumulative ionic deposits to the site comprised mostly of Na+, Cl−, and CaCO3 equivalent alkalinity, with soil analysis recovering most of the deposits (>57%) except for K+ and Na+ (8% to 13%). Subsurface leaching of and P was detected within the upper 1 m soil depth after 4 yr, and a high downward mobility of Cl− revealed the potential for deeper leaching at higher N loading rates. While long-term effects on the natural vegetation are unknown, results contribute to a limited scientific database for sustainable wastewater land application in semiarid regions.
Research Interests:
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Potatoes cv. Kennebec were watered by sprinkler, trickle, subsurface and furrow irrigation to maintain a min. soil water potential of -20 or -60 kPa. When planted on a clay loam soil where rainfall was low, the highest yield and water-use... more
Potatoes cv. Kennebec were watered by sprinkler, trickle, subsurface and furrow irrigation to maintain a min. soil water potential of -20 or -60 kPa. When planted on a clay loam soil where rainfall was low, the highest yield and water-use efficiency were achieved using a subsurface ...
Research Interests:
Page 1. Yield of Alfalfa and Cotton as Influenced by Irrigation' Theodore W. Sammis2 ... 40 35 30 25 20 15 10 5 0 1979 Sprinkler Line Source 0 1978 Sprinkler Line Source 0 Lysimeters @ curry's Lysimeters are statistically... more
Page 1. Yield of Alfalfa and Cotton as Influenced by Irrigation' Theodore W. Sammis2 ... 40 35 30 25 20 15 10 5 0 1979 Sprinkler Line Source 0 1978 Sprinkler Line Source 0 Lysimeters @ curry's Lysimeters are statistically similar (P < 0.05) and, therefore, can be combined. ...
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Trickle irrigation has become a widely used method. Its primary advantage in arid regions is that it saves water. However, because of its modernity, analytical and experimental results are minute compared to those for conventional... more
Trickle irrigation has become a widely used method. Its primary advantage in arid regions is that it saves water. However, because of its modernity, analytical and experimental results are minute compared to those for conventional irrigation methods. This study was conducted ...
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Research Interests: Civil Engineering, Irrigation, Water Engineering, Agricultural Water Management, Irrigation water use efficiency, and 13 moreSeasonality, Arboriculture, Water use efficiency, Surface energy balance, Eddy Covariance, Evapotranspiration, Irrigation Water, Water Use, Soil Heat Flux, Tree Height, Sensible Heat Flux, Flood Irrigation, and Cumulant
... density ( Pb) 1994 1993 1992 1 Chile Alfalfa Alfalfa Fine, Montmorillonitic, thermic, Armijo clay 1.35 Typic Torrerts 2 Chile Chile Chile Coarsesilty, mixed (calcreous), Thermic, Harkey loam 1.4 Typic Torrifluvent 3 Chile ... b The E,... more
... density ( Pb) 1994 1993 1992 1 Chile Alfalfa Alfalfa Fine, Montmorillonitic, thermic, Armijo clay 1.35 Typic Torrerts 2 Chile Chile Chile Coarsesilty, mixed (calcreous), Thermic, Harkey loam 1.4 Typic Torrifluvent 3 Chile ... b The E, was estimated based on a dry yield of 4136kgha1. ...
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Research Interests: Civil Engineering, Applied Mathematics, Horticulture, Irrigation, Biomass, and 24 moreBiomathematics, Modeling, Water Engineering, Resource Allocation, Agricultural Water Management, Growth, Model, Arboriculture, Water use efficiency, Evapotranspiration, Profitability, Partition, Water Use, Tree growth, Biomass Allocation, Mathematical Model, Pruning, Growth Model, Object Oriented, Simulation Model, Tree Height, Biological Model, Vapor Pressure Deficit, and Dry matter production
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ABSTRACT Spring barley was irrigated using a line source sprinkler system to impose an irrigation gradient at Las Cruces, NM, U.S.A. Canopy temperature (Tc), air temperature (Ta), and vapor pressure deficit (VPD) were measured along with... more
ABSTRACT Spring barley was irrigated using a line source sprinkler system to impose an irrigation gradient at Las Cruces, NM, U.S.A. Canopy temperature (Tc), air temperature (Ta), and vapor pressure deficit (VPD) were measured along with leaf water potential of the flag leaves during the pre- and post-heading growth stages at three moisture levels located 0, 8 and 14 m from the sprinkler line. Canopy and air temperature and VPD measurements were also taken during the senescence stage. Aboveground biomass, grain yield and 1000-grain weight were determined at the three moisture levels at the end of the growing season. Seasonal evapotranspiration was determined at each moisture level using the water balance method.The crop water stress index (CWSI) was determined as the relative position between an upper and a loswer baseline relating Tc−Ta to VPD. The baselines were different for the pre- and post-heading stages. During the senescence stage, no relationship existed between Tc−Ta and VPD for any moisture level, and the average Tc−Ta was 5.2°C with a coefficient of variation of 28%.The CWSI was significantly (P≤0.05) related to measured evapotranspiration (r2=0.99), leaf water potantial (r2=0.75), aboveground biomass (r2=0.93), grain yield (r2=0.94) and 1000-grain weight (r2=0.97).
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Research Interests:
Research Interests: Civil Engineering, Applied Mathematics, Irrigation, Water Engineering, Ecophysiology, and 20 moreAgricultural Water Management, Irrigation Management, Seasonality, Model, Water use efficiency, Eddy Covariance, Evapotranspiration, Plant growth, Estimation, Energy Balance, Relative Humidity, Water Use, Mathematical Model, Energy Budget, Above ground biomass, Dry Matter, Vapor Pressure Deficit, Covariance, Dry matter production, and Growing Season
Research Interests: Civil Engineering, Applied Mathematics, Horticulture, Remote Sensing, Irrigation, and 17 moreBiomathematics, Water Engineering, Image Analysis, Agricultural Water Management, Seasonality, Arboriculture, Eddy Covariance, Evapotranspiration, Physiological Models, Statistical Significance, Open Systems, Water Use, Tree growth, Irrigated Agriculture, Coefficient, Covariance, and Regression equation
Research Interests: Civil Engineering, Horticulture, Renewable Energy, Irrigation, Water Engineering, and 18 moreEvaluation, Micrometeorology, Agricultural Water Management, Irrigation water use efficiency, Irrigation Management, Seasonality, Arboriculture, Eddy Covariance, Flood, Evapotranspiration, Energy Balance, Cost effectiveness, Water Use, Infrared, Water Vapor, Sensible Heat Flux, Flood Irrigation, and Growing Season
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Research Interests:
ABSTRACT Nut production from pecans, almonds, and pistachios figures heavily in the economies of California, Texas, and New Mexico, as well as several other states, and surface irrigation water supplies have been reduced in low runoff... more
ABSTRACT Nut production from pecans, almonds, and pistachios figures heavily in the economies of California, Texas, and New Mexico, as well as several other states, and surface irrigation water supplies have been reduced in low runoff years in the western United States. Water and nitrogen management in tree crops is constrained through lack of information and inability to provide targeted management. The goal of this research was to develop an improved management pecan model to monitor and predict water and nutrient demand and nutrient status in pecan trees, along with the interaction of nutrient and water stress on nut yield. The pecan nut tree model developed by Andales et al. (2006) had a nutrient uptake and allocation and nutrient stress subroutine added to the model to predict the interaction of water and nutrient stress (nitrogen and potassium). The nitrogen submodel presented simulates the interaction of nitrogen transformation, soil temperature, water, and nitrogen uptake to describe nitrate distribution in the root zone of a growing pecan tree for the entire growing season. The nitrogen submodel follows the nitrogen transformation equation developed by Jones and Kiniry (1986) for the CERES-maize model. The nitrogen root uptake submodel follows the approach developed by Yanai (1994), which is a model of solute uptake that accepts root growth, water uptake, and soil solution concentrations as time-varying inputs that interactively link plant and soil processes. The model was tested against a nitrogen–potassium water stress experiment conducted by Smith et al. (1985) in Oklahoma from 1978 to 1983 where the pecan trees received varying rainfall amounts, the only source of water, and four levels of nitrogen application. The measured yield response represented a water nitrogen stress response. The model over-predicted the yield by 42% compared to the measured yield, but the model under-predicted yield by 21% in 1981 with 0 kg/ha of applied N and under-predicted yield by 13% when 224 kg/ha N was applied that year. The current pecan model appears to simulate water stress reasonably well but may overestimate the nitrogen uptake by the pecan trees and underestimate the reduction in yield caused by nitrogen stress. The model also may overestimate yield through lack of an insect damage submodel.
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Land application should maximize vegeta- tive cover to increase the capacity of a site to serve as a sink for wastewater contami- nants, minimize salt accumulation in the root zone, and avoid nitrate leaching into the groundwater. Irri-... more
Land application should maximize vegeta- tive cover to increase the capacity of a site to serve as a sink for wastewater contami- nants, minimize salt accumulation in the root zone, and avoid nitrate leaching into the groundwater. Irri- gation scheduling is a management practice ...
Research Interests:
Soils of northwest New Mexico have an elevated pH and CaCO 3 content that reduces Fe solubility, causes chlorosis, and reduces crop yields. Could biosolids and fly ash, enriched with Fe, provide safe alternatives to expensive Fe EDDHA... more
Soils of northwest New Mexico have an elevated pH and CaCO 3 content that reduces Fe solubility, causes chlorosis, and reduces crop yields. Could biosolids and fly ash, enriched with Fe, provide safe alternatives to expensive Fe EDDHA (sodium ferric ethylenediamine ...