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The Northern Gulf of Mexico hosts a severe dead zone, an oxygen-depleted area spanning 1,618,000 hectares, threatening over 40% of the U.S. fishing industry and causing annual losses of USD 82 million. Using a System Dynamics (SD) approach, this study examined the Mississippi–Atchafalaya River Basin (MARB), a major contributor to hypoxia in the Gulf. A dynamic model, developed with Vensim software version 10.2.1 andexisting data, represented the physical, biological, and chemical processes leading to eutrophication and simulated dead zone formation over time. Various policies were assessed, considering natural system variability. The findings showed that focusing solely on nitrogen control reduced the dead zone but required greater intensity or managing other inputs to meet environmental goals. Runoff control policies delayed nutrient discharge but did not significantly alter long-term outcomes. Extreme condition tests highlighted the critical role of runoff dynamics, dependent on nitrogen load relative to flow volume from upstream. The model suggests interventions should not just reduce eutrophication inputs but enhance factors slowing down the process, allowing natural denitrification to override anthropogenic nitrification. 

Morphological and anatomical measurements of Solanum lycopersicum L. seedlings grown with diluted seawater in the greenhouse were analyzed to understand the effects of non-conventional water on the growth and development of the species. The salinity of the non-conventional water ranged from 8.15mS/cm to 9.85mS/cm which corresponds to 0.5% to 2.0% seawater (v/v) in freshwater dilution. The results indicate that no significant difference exists in anatomical and morphological growth and development of the species compared to those grown with freshwater. Thee study concludes that adoption of this type of non-conventional water resource in greenhouse crop production will save between 415,000 to 1,660,000 liters of freshwater for the United States fresh harvest-producing greenhouses per day. It further concludes that the results represent an effective freshwater conservation strategy for the United States and the world at large. 

Inorganic fertilizers are often used in the United States in golf courses putting green maintenance. We used milled plant biomass on putting greens to test the hypothesis that organic biostimulants used in putting green maintenance can achieve similar results as inorganic fertilizers. Dilapidated putting greens, #4 and #14, with conspicuous patches at the L.E. Ramey Golf Course in Kingsville, TX, were selected for the study. Each green was split in half with one half selected for treatment and the other half maintained as the control and treated with NPK. Milled Medicago sativa L. mixed with milled high auxin-containing plant species in a ratio of 10:1 was used to test the hypothesis. The mixture was applied in the bio-treated section of the two greens while the golf course management continued to apply inorganic fertilizers on the control section of the study greens. Patch count on the greens was conducted once a week utilizing a randomly placed 1 by 1 m quadrant. Also, soil moisture measurement was taken twice a week on the greens to understand soil moisture retention due to the treatments. Patch count indicates that the bio-treated sections grew and filled significantly faster than the sections treated with inorganic fertilizers. Regression analysis of data collected between July 13th and July 27th indicates a strong linear biostimulant/patch growth relationship (R2 = 0.75 and 0.92) on Greens #4 and #14 respectively. Also, soil moisture data indicates significantly higher moisture retention on the putting green sections treated with the biostimulant. 

An experiment was conducted in the greenhouse to study growth, development, yield and water-use by Anahein pepper grown in a potting mixture supplemented with MiracleGro® (9:4:12) and milled alfalfa (3:1:2) as sources of nutrient. The study was comprised of 5 treatments, control (C), 3 gL-1 MiracleGro® (MG), 9 g alfalfa mill supplement (SA-1), 18 g (SA-2), and 27 g (SA-3), and replicated 6 times. Ten physiological and morphological parameters were used to evaluate growth, development and yield of the Anaheim pepper, and two parameters used to evaluate the water holding capacity of the potting mixture. The results indicate that the potting medium supplemented with alfalfa mill required significantly less water to support growth and development of the species. Also, growth, development and yield of Anaheim pepper was significantly higher in the organic supplements at SA-2 and SA-3. 

Water is a vital component for agricultural productivity; however, freshwater supplies are limited and are dwindling worldwide. Water for agriculture is an extreme issue for the southern region of Texas, where water supplies from reservoirs are used for municipal, industrial, and agricultural purposes. Due to intensive and prolonged intermittent droughts in south Texas, freshwater sources can deplete rapidly leaving growers on water restrictions. One potential solution of reducing the amount of water for crops is by applying less water than recommended crop evapotranspiration requires. Deficit irrigation (DI) is the practice of applying lower amounts of water than general crop requirements to increase water use efficiency for economic benefit. Deficit irrigation practice has been shown to be beneficial to some fruit and vegetable crops, but to a lesser extent in south Texas for mild heat pepper plant production. The purpose of this project was to analyze how watering jalapeño and serrano pepper plants at different levels of DI would impact plant growth and fruit yield in a greenhouse study. Deficit irrigation treatments were performed by irrigating pots at increasing the number of days between irrigation events (water application: 2, 4, 8, and 12 days) to create increasing water stress levels to plants. Plant growth and biomass data was collected to determine the impact of increasing deficit irrigation on plant shoot productivity. In both varieties, plant biomass steadily decreased as water application decreased. Serrano peppers grown at both 4d and 2d between water application events produced identical yields, however, increased water stress immediately impacted jalapeño peppers with lower yield. The encouraging results from serrano peppers suggest a potential economic benefit for deficit irrigation water use practices applied to this pepper variety. 

Water is a vital component for agricultural productivity; however, freshwater supplies are limited and are dwindling worldwide. Water for agriculture is an extreme issue for the southern region of Texas, where water supplies from reservoirs are used for municipal, industrial, and agricultural purposes. Due to intensive and prolonged intermittent droughts in south Texas, freshwater sources can deplete rapidly leaving growers on water restrictions. One potential solution of reducing the amount of water for crops is by applying less water than recommended crop evapotranspiration requires. Deficit irrigation (DI) is the practice of applying lower amounts of water than general crop requirements to increase water use efficiency for economic benefit. Deficit irrigation practice has been shown to be beneficial to some fruit and vegetable crops, but to a lesser extent in south Texas for mild heat pepper plant production. The purpose of this project was to analyze how watering jalapeño and serrano pepper plants at different levels of DI would impact plant growth and fruit yield in a greenhouse study. Deficit irrigation treatments were performed by irrigating pots at increasing the number of days between irrigation events (water application: 2, 4, 8, and 12 days) to create increasing water stress levels to plants. Plant growth and biomass data was collected to determine the impact of increasing deficit irrigation on plant shoot productivity. In both varieties, plant biomass steadily decreased as water application decreased. Serrano peppers grown at both 4d and 2d between water application events produced identical yields, however, increased water stress immediately impacted jalapeño peppers with lower yield. The encouraging results from serrano peppers suggest a potential economic benefit for deficit irrigation water use practices applied to this pepper variety. 

Morphological and anatomical measurements of Solanum lycopersicum L. seedlings grown with diluted seawater in the greenhouse were analyzed to understand the effects of non-conventional water on the growth and development of the species. The salinity of the non-conventional water ranged from 8.15mS/cm to 9.85mS/cm which corresponds to 0.5% to 2.0% seawater (v/v) in freshwater dilution. The results indicate that no significant difference exists in anatomical and morphological growth and development of the species compared to those grown with freshwater. The study concludes that adoption of this type of non-conventional water resource in greenhouse crop production will save between 415,000 to 1,660,000 liters of freshwater for the United States fresh harvest-producing greenhouses per day. It further concludes that the results represent an effective freshwater conservation strategy for the United States and the world at large.