Effect of Municipal Treated Wastewater and Brackish Groundwater on the Water Holding Properties of a Clayey, Calcareous Soil

Wastewater reuse is a practice that has been gaining attention for the past few decades as the world’s population rises and water resources become scarce. This study compared the long-term (15+ years) effects and suitability of using secondary-level treated municipal wastewater and brackish groundwater for irrigation on the water holding capacity of a clayey, calcareous soil on a cotton farm near San Angelo, Texas. The soil-water holding properties were determined from the extracted hydrostructural parameters of the two characteristic curves: water retention curve and soil shrinkage curve based on the pedostructure concept. In the pedostructure concept, these hydrostructural parameters are characteristic parameters of the soil aggregates structure and its thermodynamic interactions with water. Results indicate that use of secondary treated wastewater increased available water capacity in the top horizon (0-15 cm) and decreased the available water holding capacity of this particular soil in the sub-horizons (15-72 cm). The brackish groundwater irrigation resulted in no effect on available water capacity in the top horizon, but significantly decreased it in the sub-horizons as well. The rainfed soil was the healthiest soil in terms of water holding capacity, but rainfall conditions do not produce profitable cotton yields due to insufficient water. Whereas, treated wastewater irrigated soil is producing the highest yields for the farmer. Thus, this treated wastewater source and irrigation system can serve as a suitable irrigation alternative to using brackish groundwater, enhancing the water resource sustainability of this region

THE EFFECT OF GREYWATER IRRIGATION ON THE HYDRO-STRUCTURAL PROPERTIES OF SOIL

As population increases, resources critical for human existence - water, food, and energy - become increasingly scarce, making it imperative to conserve, reuse, and recycle these resources. A largely untapped, non-conventional source for water reuse is greywater. This project assesses the effects of greywater irrigation on soil from a household landscape in the laboratory by applying controlled percolation cycles. All soil samples were characterized using a new apparatus (TypoSoilTM) to determine changes in soil hydro-structural properties. The main conclusions drawn from this study are that greywater irrigation affects the basic structure of the soil medium and reduces the soil’s ability to store water, thus reducing the water availability within the soil for plants to use. In cases of greywater use in agriculture, this effect will impact irrigation frequency and will increase the need for better farm water management

THE EFFECT OF GREYWATER IRRIGATION ON THE HYDRO-STRUCTURAL PROPERTIES OF SOIL

As population increases, resources critical for human existence - water, food, and energy - become increasingly scarce, making it imperative to conserve, reuse, and recycle these resources. A largely untapped, non-conventional source for water reuse is greywater. This project assesses the effects of greywater irrigation on soil from a household landscape in the laboratory by applying controlled percolation cycles. All soil samples were characterized using a new apparatus (TypoSoilTM) to determine changes in soil hydro-structural properties. The main conclusions drawn from this study are that greywater irrigation affects the basic structure of the soil medium and reduces the soil’s ability to store water, thus reducing the water availability within the soil for plants to use. In cases of greywater use in agriculture, this effect will impact irrigation frequency and will increase the need for better farm water management

State of the Art of Water for Food Within the Nexus Framework

Purpose of Review: The purpose of this study is to evaluate the state of knowledge regarding water for food within the water-energy-food (WEF) nexus framework. Three topics are considered: improved plant genetics; irrigation technology and practices; and urban agriculture. Recent Findings: Research in plant genetics has sought to understand plant mechanisms that produce higher-yielding crops, identify and map genetic loci regions responsible for desirable plant traits, and introduce new and safe methods of precision plant breeding. In addition, new discoveries in irrigation practices are crucial in sustaining and further increasing yields as a result of improved irrigation water use efficiency through near-real time spatio-temporal monitoring of soil moisture, evapotranspiration, and rainfall. Urban agriculture has been proliferating in recent years, and recent research demonstrates the possibility of non-traditional, urban farming methods to produce food in a water- and land-efficient way. Summary: Opportunities remain to increase water use efficiency and/or decrease water usage throughout the food supply chain. Food producers need to achieve greater value from the water used through enhanced management supported by new technology and guided by scientific findings evolving from multidisciplinary research. To achieve this, constant exchange is needed between regulatory agencies, farmers, food manufacturers, and researchers to ensure all stakeholders are up to date on the issues, policies, technologies, and discoveries related to water and food production sustainability

Comparison of the anaerobic microbiota of deep-water Geodia spp. and sandy sediments in the Straits of Florida

Marine sediments and sponges may show steep variations in redox potential, providing niches for both aerobic and anaerobic microorganisms. Geodia spp. and sediment specimens from the Straits of Florida were fixed using paraformaldehyde and 95% ethanol (v/v) for fluorescence in situ hybridization (FISH). In addition, homogenates of sponge and sediment samples were incubated anaerobically on various cysteine supplemented agars. FISH analysis showed a prominent similarity of microbiota in sediments and Geodia spp. samples. Furthermore, the presence of sulfate-reducing and annamox bacteria as well as other obligate anaerobic microorganisms in both Geodia spp. and sediment samples were also confirmed. Anaerobic cultures obtained from the homogenates allowed the isolation of a variety of facultative anaerobes, primarily Bacillus spp. and Vibrio spp. Obligate anaerobes such as Desulfovibrio spp. and Clostridium spp. were also found. We also provide the first evidence for a culturable marine member of the Chloroflexi, which may enter into symbiotic relationships with deep-water sponges such as Geodia spp. Resuspended sediment particles, may provide a source of microorganisms able to associate or form a symbiotic relationship with sponges. © 2010 International Society for Microbial Ecology All rights reserved