Total Water Usage Research Articles

Growth enhancement and antitranspirant activity following seed treatment with a derivative of 5‐hydroxybenzimidazole (Ambiol) in four drought‐stressed agricultural species

The biostimulating action of seed treatment with the synthetic antioxidant, Ambiol (2‐methyl‐4‐Edimethylaminomethyl‐5‐hydroxybenzimidazole dihydrochloride) on subsequent growth and transpiration of seedlings was studied. To study growth and transpiration responses, seeds of four agricultural species, soybean (Glycine max L.), rapeseed (Brassica napus L.), winter wheat (Trilicum aestivum L.) and corn (Zea mays L.), were soaked in Ambiol for 24 h, using the following concentrations: 0, 0.01, 0.1, 1, 10 and 100 mg 11. The subsequent seedlings were subject to simulated soil drought, using computer‐automated root misting chambers. The influence of Ambiot on transpiration rate under simulated air drought was studied by growing plants under low humidity in a controlled humidity chamber. Response to Ambiol varied, depending on its concentration, the species used and the environment. Compared to untreated plants, 10 mg 1‐−1 Ambiol reduced the mid‐day transpiration rate and total daily water usage of soybean by approximately 25%. Under simulated soil drought in the root misting chamber, 10 and 100 mg 1‐−1 Ambiol increased growth of rapeseed and soybean by 25–45%, relative to the 0 mg 1‐−1 treatment, yielding plants comparable in size to the fully‐irrigated controls. However, Ambiol failed to promote growth of two drought‐stressed monocotyledons (corn and winter wheat). At 100 mg P. Ambiol inhibited growth of both well‐watered wheat and rapeseed, although this inhibition was mitigated by drought.

Case study of waste water minimization at a general electric manufacturing plant

AbstractThis paper describes the process of converting an existing industrial water system at a General Electric manufacturing plant towards zero discharge. A plan to significantly reduce waste water to the publicly owned treatment works (POTW) is presented. The first phase, which should reduce water discharge by 90% compared to 1992 rates, involves three major steps. First, a vibrating membrane filter machine will be used to treat the tumbler machine waste water, which accounts for about half of the plant's total water usage. The suspended solids in the waste water will be removed and disposed of as non‐hazardous waste. The water will be reused in the tumbler room and in other processes throughout the plant. Second, effluent from the waste water treatment plant will be recycled to the maximum extent possible. Third, steps will be taken to minimize water usage in rinsing operations. When the first phase is completed, the water quality in the plant will be expected to change. In particular, the salt concentration will increase, and the temperature of the water may rise. With careful monitoring of the water quality, input rates of city water, and discharge rates, a zero‐discharge system can be defined. The key to achieving zero‐discharge will be selecting a technology to remove salts from the water. The likely candidates are reverse osmosis, electrodialysis, or ion exchange, perhaps followed by evaporation to reduce the brine volume. A preliminary design for a zero‐discharge system is presented; however, the first phase of the project will be implemented and studied before the appropriate salt‐removing technology is selected.

Potato growth and yield using nutrient film technique (NFT)

Potato plants, cvs Denali and Norland, were grown in polyvinyl chloride (PVC) trays using a continuous flowing nutrient film technique (NFT) to study tuber yield for NASA's Controlled Ecological Life Support Systems (CELSS) program. Nutrient solution pH was controlled automatically using 0.39M (2.5% (v/v) nitric acid (HNO3), while water and nutrients were replenished manually each day and twice each week, respectively. Plants were spaced either one or two per tray, allotting 0.2 or 0.4 m2 per plant. All plants were harvested after 112 days. Denali plants yielded 2850 and 2800 g tuber fresh weight from the one- and two-plant trays, respectively, while Norland plants yielded 1800 and 2400 g tuber fresh weight from the one- and two-plant trays. Many tubers of both cultivars showed injury to the periderm tissue, possibly caused by salt accumulation from the nutrient solution on the surface. Total system water usage throughout the study for all the plants equaled 709 liters (L), or approximately 2 L m-2 d-1. Total system acid usage throughout the study (for nutrient solution pH control) equaled 6.60 L, or 18.4 ml m-2 d-1 (7.2 mmol m-2 d-1). The results demonstrate that continuous flowing nutrient film technique can be used for tuber production with acceptable yields for the CELSS program.

Soil Water Depletion Under Crops on Reclaimed and Undisturbed Soils

AbstractSoil water depletion by profile depth increments and total water usage were measured yearly under either small grains or corn (Zea mays L.) over a 4‐yr period on undisturbed Williams loam (fine‐loamy, mixed Typic Argiborolls) and soil reclaimed following simulated stripmining. The reclaimed soil had topsoil thicknesses of either 0.23, 0.46, or 0.69 m respread over nonsaline, nonsodic spoil materials whose textures were gravelly loamy sand with and without a clay loam subsoil, clay loam, or silty clay loam. Total water usage and soil water depletion (for profile depths of 0 to 0.6 m and 0.6 to 1.5 m) were consistently greater, but essentially significant (P = 0.10) only in 1 yr, for the undisturbed compared to the reclaimed soil (averaged over topsoil thickness or spoil texture). Grain or biomass yields were significantly higher for the undisturbed compared with the reclaimed soil when growing‐season precipitation was inadequate or poorly distributed. Shallower rooting depths and thus lesser soil water depletion even though the reclaimed soil had similar amounts of plant‐available soil water at planting for 3 of the 4 yr resulted in water stress conditions and reduced potential productivity in inadequate precipitation years on the reclaimed soil. Similar water‐use efficiency values were found for both the undisturbed and reclaimed soils for all 4 yr. If amounts of available soil water at planting and soil water depletion values had been more uniform between the undisturbed and reclaimed soils, the reclaimed soil most likely would have met the reclamation law requirement of “equal or better than” productivity present prior to mining (undisturbed soil productivity) for all 4 yr.

An Application of Bayes Methodology to the Analysis of Diary Records from a Water Use Study

Abstract One of the objectives of a comprehensive domestic water use study conducted in Perth, Western Australia, was the quantification of components of water usage. Each household in a sample of about 3,000 was asked to record all water uses in a specially provided diary for a 2-week period, and the total water usage, both in-house and ex-house, was metered daily during this time. This article describes an application of Bayesian methodology to the estimation of usage for each in-house water-using activity for each house on each day of participation. The estimation procedure allows for inaccuracies in the diary records and incorporates prior information on the distributions of certain rates and volumes over houses. The prior information came from intensive data collection on a prior sample of about 150 households.

Atrazine Uptake by Sudangrass, Sorghum, and Corn

The uptake of 2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine (atrazine) was studied in sudangrass [Sorghum sudanense(Piper) Stapf, var. Piper], grain sorghum [Sorghum bicolor(L.) Moench], and corn (Zea maysL.) to find whether differences in atrazine uptake exist among these species. The uptake of atrazine followed closely the growth patterns of corn, sorghum, and sudangrass during the first 5 weeks of growth. Concentration of14C from ring-labeled14C-atrazine in the soil reached a peak in corn, sorghum, and sudangrass plants after 2 weeks of growth and then declined. The14C concentrations were two to three times greater in sorghum and sudangrass than in corn throughout the 5-week period. Atrazine uptake per gram of plant growth by these crops was directly proportional to the concentration of atrazine in the soil and the proportionality factors were in the order: sudangrass < sorghum ≫ corn. Total uptake and the total growth were in order: corn ≫ sorghum = sudangrass. In a study where relative humidity was a variable, the amount of atrazine absorbed per ml of water was inversely related to total water usage.

Effect of Fatty Alcohol on Evaporation and Transpiration1

SynopsisTotal water usage, evaporation, and plant growth were reduced. Transpiration was reduced by the first increment of fatty alcohol, due to decreased plant growth, but no further change occurred with additional increments. All treatments required the same amount of transpiration water to produce one gram of oven‐dry material. Total water usage per gram of material actually increased with the addition of alcohol because plant growth was decreased proportionately more than transpiration.