In the following paragraphs, different research activities carried out by faculty, undergraduate and graduate students are briefly described.

Wireless Sensor Network (WSN) for Monitoring Groundwater Levels at an In-Situ Recovery (ISR) Uranium Mining Site (Dr. Lee Clapp, Mr. Corando Gallegos)

Due to over-reliance on freshwater aquifer resources, falling groundwater tables are a concern throughout much of Texas and other semi-arid regions. Groundwater tables in some areas of Texas have recently been declining at rates of over 50 feet per year, with irrigation being the dominant water user. For agricultural and mining activities in Texas that rely on intensive groundwater pumping, access to near real-time groundwater elevation data is critical for effective groundwater management. Unfortunately, obtaining dependable real-time groundwater table data can be difficult, particularly in dispersed remote areas. To address this problem, Dr. Clapp’s research team is assessing the deployment of a remote wireless sensor network (WSN) for real-time monitoring of groundwater levels at in-situ recovery (ISR) uranium mining sites in Texas. ISR is a “solution mining” practice that involves injecting oxygen-amended groundwater into aquifers in uranium ore zones, then pumping the resulting “lixiviant” to the surface where solubilized uranium is extracted by ion exchange (IX). Hydraulic control is achieved by creating a groundwater “cone of depression” at the site by removing a 3% “bleed” from the IX-treated lixiviant before re-amending it with oxygen and re-injecting it into the formation. The hydraulic bleed is injected into a permitted deep injection well thousands of feet below the freshwater aquifer.  Maintaining the cone of depression is critical for preventing “excursions” of mining solutions away from the site; however, creating an excessive cone of depression needlessly consumes groundwater. Dr. Clapp’s lab is assessing the specific application of using WSNs to improve hydraulic control at ISR mining sites.

Remote Soil Monitoring using UAS (Dr. Selahattin Ozcelik, Mr. Juan Rodriguez, Mr. Kyle Barton, Ms. Genesis Cantu, Mr. Isaac Olson)

Water is a critical resource for sustainable crop production systems in the U.S. and worldwide and limited soil water availability reduces crop growth more than all other environmental factors combined. Thus, improving crop production under water-limited conditions has become the primary goal of agricultural scientists. To the effect, the integration of Unmanned Aerial Systems (UAS) is investigated for wirelessly monitoring soil moisture and crop productivity. The research team developed a system using Unmanned Aerial Vehicles (UAVs) to allow easy access to remote fields even when infrastructure does not allow it. This was done by incorporating a high-efficiency, high-payload multirotor drone where the intended area of operations can now be accessed at will. By using a UAV, the system is no longer dependent on the status of a road or if a cell network is down. This system consisted of two elements; a sensor node, measuring soil moisture, temperature, and electrical conductivity, and a receiver node. The sensor node contains the equipment necessary to interface with the sensors, while the receiver node is equipped to wirelessly transfer data from the sensor node to a website directly. In this configuration, a UAV carries the receiver node within the connection range of the sensor node. The system makes a fast connection to transfer the data from the sensor node to the receiver node. Then, after the sensor data has been uploaded to the receiver node, the UAV brings the receiver node within range of a Wi-Fi network. Once there, the receiver node uploads the data to the website.

Effective monitoring dynamic groundwater conditions by using Wireless Sensor Networks (Dr. Nuri Yilmazer, Mr. Taofiki Saliyu, Mr. Joaquin Massa)

The Wintergarden region in Texas has become one of the leading producers of winter vegetables in the country. Crop production in this region is primarily achieved using central pivot irrigation systems that rely heavily on groundwater. So, there is a need to develop an accurate and reliable groundwater level monitoring system. Integrated groundwater WSN sensors have significant potential for more effectively monitoring dynamic groundwater conditions than traditional monitoring techniques by providing greater spatial and temporal resolution, particularly in remote areas. Our research teams research objectives are to: 1) Develop, deploy, and assess a reliable WSN for continuous real-time remote monitoring of groundwater levels and conductivities near a central pivot irrigation system in the Wintergarden region; 2) Design and investigate better communication systems and node architectures; 3) Develop beam-forming techniques for dispersed WSNs that will improve coverage and reduce power consumption; 3) Integrate the WSN with a web-based platform for sharing and visualizing real-time groundwater data with regional stakeholders.

Wireless Sensor Network Deployed on Campus

 

Water management strategies to sustain crop production (Dr. Shad Nelson, Dr. M. Setamou, Dr. A. Bhandari, Mr. Desiderio De Leon, Ms. Eva Morgan)

South Texas is considered a semi-arid environment despite the fact that average rainfall exceeds 20 inches annually.  Although humidity levels commonly exceed 80% throughout the region, rainfall distribution is sporadic where heavy rainfall events large events are dominant in only a few months per year.  This leads to high evaporative demand on crops is the reason why south Texas is semi-arid climatic conditions.  Thus, supplemental irrigation is essential for horticultural crop production, especially for perennial crops like citrus.  The Lower Rio Grande Valley is a critical horticultural producing region of the state, where surface water is used to make up crop water demands.  The dominant irrigation method in this region for citrus production is by flood irrigation, while furrow irrigation methods are used for other horticulture crops like tomatoes, peppers, onions, squash, lettuce, etc.  These irrigation practices lead to high water loss via evaporation, off-site water movement, or leaching beyond the effective rooting zone of crops.   The emphasis of this research is to evaluate water management strategies to sustain crop production with lower water use principles and/or soil management techniques.

 

Evaluation of ecosystem services of annual cover crops in Texas citrus orchards (Dr. Joel Cabrera, Ms. Leticia Robles)

The Lower Rio Grande Valley (LRGV) agricultural region is susceptible to climatic changes affecting high-value specialty crops, such as citrus orchards. Supplemental irrigation is used by citrus producers to meet citrus water demands. There are multiple water delivery systems for citrus production, but the preferred irrigation method is flooding. However, flood irrigation is very inefficient because a large quantity of water is lost and a small quantity reaches the tree rootzone. The main goal of the research is to plant cover crops (CC) and observe the effects of water infiltration, as well as weed control and soil organic matter (SOM) composition. To assess the incorporation of cover crops on these variables two experiments will be conducted. Experiment I will be conducted in a grapefruit (Citrus x paradisi.) orchard, while Experiment II will be conducted in controlled conditions. Three annual cover crops will be evaluated for these experiments: Buckwheat (Fagopyrum esculentum), Sunn hemp (Crotalaria juncea L.), and Sunflower (Helianthus annuus). Experiment I will assess CC planted in empty spaces between grapefruit rows in field conditions. Experiment II will serve to study SOM composition and water consumption of cover crops. The findings will aid in determining if CC are beneficial to citrus orchards, and which CC could increase citrus resilience to changing climatic conditions.

 

Amending Soils for Water Conservation (Dr. Greta Schuster, Ms. Amberley Zaragoza)

Water is critical for agricultural production worldwide and plays an important role in food security. The effect of water, from either precipitation and/or irrigation, on the cropping systems of the South Texas has been the subject of early and numerous studies. In emerging dryland cropping systems, the emphasis is to capture and to retain precipitation throughout the year and mainly during the growing season.  Good soil is the foundation to efficient water use and healthy plants. Along with best management practices, the addition of organic matter is one of the best ways to improve soils. Increasing soil organic matter increases infiltration rates in clay soils to reduce runoff of water and nutrients. It improves the water- and nutrient-holding capacity of sandy soils to decrease water and nutrients lost to drainage. (Amending Soils for Water Conservation)

 

Effect of land management and cover crop mixtures on soil physicochemical properties in a Long-term research field (Dr. Sanku Dattamudi, Mr. Erik Zamora)

South Texas is facing serious shortage of rainfall from last few years which resulted in crop failures and major economic losses. Land management practices and cover cropping has the potentiality to retain more soil moisture through better soil structure and soil aggregate stability. Therefore, the current project is evaluating the effectiveness of cover crop mixtures on improving water holding capacity in a cotton-sorghum crop field at Corpus Center. Other ecosystem services including organic carbon accumulation and increase in other nutrients of the soil are major expected outcomes of this project.

 

Groundwater Resources and Water Quality in the Winter Garden and Coastal Bend Regions of South Texas (Dr. Matthew Alexander, Dr. Joseph Amaya, Mr. Jose Garcia, Mr. Hafiz M Aamir, Ms. Kaitlyn Smith, Ms. Ilde Vivero, Mr. Fabian Maldonado, Mr. Joseph Saenz, Mr. Joshua Gallegos, Mr. Jorge Hernandez, Ms. Ysenia Grandos, Mr. Michael Ramos, Ms. Marilyn Coronado)

Water resources, both groundwater and surface water, are scarce in semi-arid regions of South Texas, including the Winter Garden region west of San Antonio and in the Coastal Bend area near Corpus Christi, Texas.  The research group directed by Drs. Amaya and Alexander has taken on several different water resource topics, including analysis of the primary water source in the Winter Garden region, which is the southern portion of the Carrizo-Wilcox aquifer.  The declining water levels of this aquifer, along with the salinity of the waters recoverable from the aquifer, are investigated using groundwater modeling and analysis of publicly available data.  Water resources in the Coastal Bend area, consisting primarily of surface water sources such as the Nueces River and Corpus Christi Bay, and to a limited extent groundwater resources in the area, have been analyzed with respect to their ability to meet necessary demands of the population in the area.

 

Plant Pathogen Threats to Irrigation Water from the Rio Grande River (Dr. Veronica Ancona, Ms. Sabrina Garza, Ms. Miriam Calderon)

The Lower Rio Grande Valley of South Texas is an important region for agriculture which depends on the Rio Grande River as a source of water for irrigation. The suitability of the river water for irrigation is dependent on many factors, including levels of total dissolved solids, salts, the presence of coliforms and other contaminants. Several studies that monitor these quality parameters have been reported, but have overlooked the presence of plant pathogens which can be distributed by river water and affect crop viability and productivity. To address this concern, the Ancona lab has focused on the evaluation of river water used for irrigation for the isolation, identification, and monitoring of fungal plant pathogens.

 

Monitoring and Impacts of Micro- and Nano- Plastics of Irrigation Water from the Rio Grande River (Dr. Veronica Ancona, Dr. Jianhong-Jennifer Ren, Mr. Seth Kuby, Ms. Vanessa Almazan Ms. Olivia Garcia, Mr. Victor Garcia)

A supplemental grant from NSF to initiate the ‘Center for Micro-Nano-Plastic Science, Technology, Innovation, and Control (μnPlaSTIC)’ was funded to address the challenges of micro- and nano- plastics in diverse environments. In this project, the Ancona lab in collaboration with Ren’s lab, is focusing in monitoring micro- and nano- plastics in the water from the irrigation distribution system in the Lower Rio Grande Valley and assessing their impact to the agroecosystem.

 

Coastal watershed hydrology and pollutant loading and their impacts on bays’ and estuaries’ water quality (Dr. Jianhong-Jennifer Ren, Mr. Kurtis M Kuypers, Ms. Miranda De La Garza, Ms. Jessica Cervantes, Mr. Alberto Aguirre)

The South Texas region including the Coastal Bend and the Rio Grande Valley of Texas is experiencing a multitude of environmental challenges impacting both natural and diverse societal ecosystems. Particularly, coastal bays and estuaries are often subject to water quality deterioration involving nutrients, sediments, and emerging contaminants due to pollution from adjacent watersheds. These issues cause a wide range of environmental and humanitarian stresses such as excessive algal blooms, lower dissolved oxygen, fish kills, and poor water quality in the water supply for agriculture and other uses. Factors that contribute to these issues range from direct human activities such as land use changes occurring in adjacent watersheds to natural events such as seasonal flooding and hurricanes. To help address these environmental sustainability issues, Ren’s group has focused on implementing and applying process-based models, combined with laboratory and field scale studies, to elucidate factors controlling the fundamental processes involved in these issues and thus facilitating the identification of effective solutions.

 

Research on Modeling and Dynamic Forecasting and Decision Support System (Dr. Tushar Sinha, Mr. Ricardo Javier Torres, Ms. Danielle Maynard, Ms. Janay Garza, Ms. Jodi Swaenpoel, Ms. Madilyn Dugosh)

Dr. Sinha is leading the Modeling and Dynamic Forecasting subproject, which focuses on improving management of surface water and groundwater and quality in three water planning areas: a) Winter Garden region in central Texas, b) Coastal Bend region, and c) Lower Rio Grande Valley (LRGV) regions in southern Texas. Dr. Sinha’s research lab focuses on issues related to urbanization and climate change and their effects on water quantity and quality of multiple watersheds located in South Texas. Addressing these issues involves developing strategies to improve water quality of streams, mitigate flooding and improve management of water resources. Dr. Sinha’s group also work on developing interfaces to visualize and query geospatial datasets.      

 

Development of Decision-Making Models (Dr. Benjamin Turner, Mr. James Russell, Ms. Kendall (Cloud) Schroeder, Ms. Julianna Leal, Mr. Caleb Reed, Mr. Chris Flores-Lopez, Mr. Lane Michna, Ms. Erica Salinas, Mr. Henry Burns, Mr. Nicolas Cavazos)

Dr. Benjamin Turner contributes to the CREST-SWU effort through collaboration across all three subprojects – Monitoring and Information Systems (MIS), Modeling and Dynamic Forecasting (MDF), and Decision Support Systems (DSS, which he also leads). The focus of the DSS subproject is to develop decision making models unique to South Texas’ regional water management issues so that stakeholders can rapidly experiment with alternative climate, policy, or management scenarios to assess the anticipated effects across social, economic, hydrologic, agronomic, and environmental domains.