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With escalating fertilizer prices, interest in using poultry litter as a source of plant nutrients has increased. However, the rapid decomposition of litter, particularly in the hot and humid southern United States, makes poultry litter vulnerable to loss of nutrients. Biochar and lignite have been proposed to mitigate nutrient loss, particularly N. However, information on the integration of biochar and lignite with poultry litter on cotton (Gossypium hirsutum L.) growth and yield is limited under southeastern agro‐ecosystems. A field experiment was conducted on a Leeper silty clay loam soil from 2017 to 2020 to evaluate the combined effect of poultry litter and inorganic N fertilizer with biochar and lignite on cotton growth, yield, and nutrient utilization. The treatments consisted of a 3 × 3 full‐factorial arrangement of amendments and fertilization types organized in a randomized complete block design. Application rates were 6.7 Mg ha–1 for poultry litter, 6.7 Mg ha–1 for biochar and lignite, and 134 kg N ha–1 for inorganic fertilizer. Lignite and biochar were only added once. The combination of biochar and lignite with poultry litter and inorganic fertilizer was positively effective on yield and yield components. Integration of biochar with poultry litter and inorganic fertilizer increased lint yield by 42 and 44% as compared with fertilization alone. Cotton leaf area index increased by 34 and 51% when biochar and lignite were combined with inorganic fertilizer in 2020. The leaching loss of postharvest soil NO3–N was significantly reduced by 66 and 50% when biochar and lignite were combined with inorganic fertilizer, respectively. Core Ideas: Combined biochar and lignite with poultry litter increased cotton yield.Integration of biochar and lignite with fertilization reduced NO3–N leaching loss.Poultry litter and inorganic fertilizer produced similar lint yield. [ABSTRACT FROM AUTHOR]

Irrigation research in the mid-south United States has not kept pace with a steady increase in irrigated area in recent years. This study used rainfall records from 1895 to 2016 to determine rainwater deficit and irrigation demand for soybean [Glycine max (L.) Merr.], corn (Zea mays L.), and cotton (Gossypium hirsutum L.) in the Blackland Prairie region of Mississippi with a soil water balance model developed in Structural Thinking and Experiential Learning Laboratory with Animation (STELLA) software. The longterm analysis showed annual rainfall exceeded 1125 mm in 3 out of 4 yr. Median growing season rainfall for soybean, corn, and cotton ranged from 226 to 412, 283 to 505, and 220 to 472 mm and was 30, 39, and 33% of annual rainfall in either normal or dry years, respectively. Total effective rainwater deficit (rainfall minus runoff, percolation, and evapotranspiration) during soybean, corn, and cotton growing seasons was 200, 217, and 184 mm, respectively. During the driest 25% years, the maximum effective rainwater deficit was 340, 324, and 327 mm for soybean, corn, and cotton, respectively. Across the 122-yr period, soybean, corn, and cotton did not appear to need irrigation for only 12, 17, and 14 yr; their average irrigation demand was 180, 167, and 175 mm yr–1, respectively. Soybean required irrigation from 29 June to 7 September, particularly in reproductive Growth Stage 3 (0.5-cm-long pods in the upper four nodes) to Stage 7 (pods mature in color anywhere), when the crop appeared to require at least five irrigations. [ABSTRACT FROM AUTHOR]

Poultry producers in the United States have begun using different types of bedding materials in production houses. Release into the environment of nutrients from applied poultry litter (PL) made with different bedding materials has not been investigated, and little information is available on nutrient concentrations in soils that receive broiler litter made with such materials. In this greenhouse study, two bedding materials (rice hulls and pine chips) in PL and two nutrient-immobilizing agents (gypsum and biochar) were applied to bermudagrass, and chemical and microbial contents of runoff water, soil properties, and plant growth were evaluated. Treatments with rice hull bedding material in PL had less runoff nutrient and greater soil soluble N and P compared with pine chip bedding. Gypsum and biochar both significantly reduced C, N, P, Cu, and Zn losses from the first runoff event, which were reduced by 26, 30, 37, 38, and 38% and by 25, 24, 30, 29, and 35%, respectively, but only gypsum obviously reduced these nutrients from later events. Potassium, Ca, Mg, and Mn increased by 2, 36, 11, and 9 times, respectively, and soluble P, Cu, and Fe significantly decreased by 68, 72, and 98%, respectively, in soil amended with gypsum. Rice hull PL in combination with gypsum significantly increased the growth of bermudagrass. Our results indicate that rice hull PL posed less risk for nutrient loss than pine chip PL when applied to fields and that gypsum was better than biochar for reducing runoff C, N, P, and Cu. [ABSTRACT FROM AUTHOR]

The effectiveness of fall- or winter-applied poultry litter, relative to spring-applied litter, as row crop fertilizer in the southern and southeastern United States has not been well researched. A 3-yr field study was conducted in northern Mississippi to determine the effectiveness of litter as corn (Zea mays L.) fertilizer and quantify loss of its potency when applied in the fall. he grain yield and biomass of corn that received fall-applied poultry litter (9 or 18 Mg ha-1) or 202 kg ha-1 NH4 NO3-N was compared against that of corn that received the same fertilization treatments applied in the spring including an unfertilized control. Corn fertilized with 18 Mg ha-1 litter applied in the spring produced 24% less grain yield in the first year but up to 21% more grain yield in the last 2 yr than corn fertilized with spring-applied NH4NO3. Unlike the common assumption that 50 to 65% of the total litter N is available in the same year of application, we estimated only 31% of the total N from 18 Mg ha-1 spring-applied litter was available to corn in the first year. Applying 18 Mg ha-1 litter in the fall, relative to spring, reduced grain yield by 12.8% and biomass by 15.0% when averaged across the 3 yr. These results show that applying poultry litter in the fall in regions with warm fall and winter months similar to that of northern Mississippi reduces its value as a fertilizer and could potentially increase environmental risk. [ABSTRACT FROM AUTHOR]

According to the Federal Highway Administration, almost one-quarter of the more than one-half-million U.S. bridges make use of prestressed concrete beams in their designs. In this paper, a method is presented for the total cost optimization of precast, prestressed concrete I-beam bridge systems, by taking into account the costs of the prestressed concrete, deck concrete, prestressed I-beam steel, deck reinforcing steel, and formwork. The problem is formulated as a mixed integer-discrete nonlinear programming problem and solved using the robust neural dynamics model of Adeli and Park. An example is presented to demonstrate the practical application of the methodology. Typical network convergence curves using three different network starting points demonstrate the excellent convergence and the robustness of the optimization model presented in this paper. [ABSTRACT FROM AUTHOR]

Obesity and type 2 diabetes are occurring at epidemic rates in the United States and many parts of the world. The "obesity epidemic" appears to have emerged largely from changes in our diet and reduced physical activity. An important but not well-appreciated dietary change has been the substantial increase in the amount of dietary fructose consumption from high intake of sucrose and high fructose corn syrup, a common sweetener used in the food industry. A high flux of fructose to the liver, the main organ capable of metabolizing this simple carbohydrate, perturbs glucose metabolism and glucose uptake pathways, and leads to a significantly enhanced rate of de novo lipogenesis and triglyceride (TG) synthesis, driven by the high flux of glycerol and acyl portions of TG molecules from fructose catabolism. These metabolic disturbances appear to underlie the induction of insulin resistance commonly observed with high fructose feeding in both humans and animal models. Fructose-induced insulin resistant states are commonly characterized by a profound metabolic dyslipidemia, which appears to result from hepatic and intestinal overproduction of atherogenic lipoprotein particles. Thus, emerging evidence from recent epidemiological and biochemical studies clearly suggests that the high dietary intake of fructose has rapidly become an important causative factor in the development of the metabolic syndrome. There is an urgent need for increased public awareness of the risks associated with high fructose consumption and greater efforts should be made to curb the supplementation of packaged foods with high fructose additives. The present review will discuss the trends in fructose consumption, the metabolic consequences of increased fructose intake, and the molecular mechanisms leading to fructose-induced lipogenesis, insulin resistance and metabolic dyslipidemia. [ABSTRACT FROM AUTHOR]

Bridge rating is based on the method of design: working stress design (WSD) or load factor design (LFD). A large number of older bridges were rated based on the WSD code. These WSD-based bridge ratings now have to be converted to the LFD-based rating. The LFD-based rating of steel bridges requires a detailed description of the steel girder’s geometric properties, which may not be available. In this article, a counterpropagation neural network model is presented for estimating the detailed section properties of steel bridge girders needed in the LFD-based rating based on the three cross-sectional properties used in the WSD-based rating of bridges: cross-section area, moment of inertia, and section modulus. It is demonstrated that, with proper training of the network using both standard wide-flange shape and representative plate girder data, the proposed model can generate the detailed section properties needed for LFD-based rating of steel bridges quite accurately. The result of this research can be used in an intelligent decision support system (IDSS) to help bridge engineers convert a WSD-based bridge rating to the LFD-based rating. [ABSTRACT FROM AUTHOR]

• Soil water balance variables were simulated using RZWMQ2 over past 80 years. • Annual percolation and surface runoff were quantified across rainfall patterns. • Planting wheat cover crop increased soil water storage especially within two months after terminating cover crop. • Simulated crops grain WUE for corn and soybean was improved by cover crop. • Cover crop statistically did not improve crop yields significantly. Incorporating cover crops into row crop production systems can affect soil water dynamics and crop production. However, the effect of this practice has not been well investigated in the northeast Mississippi USA. We calibrated and validated the cropping system model (Root Zone Water Quality Model, RZWQM2) using 4-yr (2014–2017) field data in the humid Mississippi Blackland Prairie, and also used this model to simulate the long-term (1938–2017) effects of a winter wheat (Triticum aestivum L.) cover crop on hydrological variables, crop yield, and water use efficiency (WUE, grain yield per unit of evapotranspiration) in a rainfed and no-tilled corn (Zea mays L.) and soybean (Glycine max L.) cropping system. Compared to no cover crop scenarios, long-term simulation demonstrates that average annual percolation under the cover crop system was decreased by 36 mm. Average annual actual evapotranspiration were 36 mm higher under cover crop system than no cover crop system. Simulated annual runoff for cover crop scenario was not different from values simulated for no cover crop scenario. Predicted actual evaporation during cash crop growth periods under cover crop plots was 25% less than under no cover crop plots due to mulch cover when averaged over the whole modeling period. Compared with no cover crop scenarios, the estimated crop evapotranspiration under cover crop scenario was reduced by 6.6% (31 mm) during corn growth period and by 3.7% (19 mm) during soybean growth period. Yearly predicted crop yields for corn and soybean did not improve, respectively, in the cover crop-based cropping system. Compared to the plots with no cover crop, the simulation of WUE for corn and soybean were respectively improved by 6.4% (1.49 kg m−3 versus 1.40 kg m−3) and by 5.0% (0.63 kg m−3 versus 0.60 kg m−3) for the plots with cover crop, largely due to the decrease in surface evaporation without sacrificing crop growth. These results suggest that long-term use of wheat cover crop to summer crops rotation is a promising practice to decrease deep percolation and restrict surface evaporation, and also improved crops WUE in the corn and soybean rotation in subtropical agro-system. [ABSTRACT FROM AUTHOR]

Profiles James M. Gere, Professor Emeritus of Civil Engineering at Stanford University in California. Educational background; Technical papers written by Gere; College textbooks authored by Gere.

Abstract: Confined animal feeding operations (CAFOs) often use anaerobic lagoons for manure treatment. In the USA, swine CAFO lagoon water is used for crop irrigation that is regulated by farm-specific nutrient management plans (NMPs). Implementation of stricter US environmental regulations in 2013 will set soil P limits; impacting land applications of manure and requiring revision of NMPs. Precise knowledge of lagoon water quality is needed for formulating NMPs, for understanding losses of N and C in ammonia and greenhouse gas emissions, and for understanding risks of environmental contamination by fecal bacteria, including zoonotic pathogens. In this study we determined year-round levels of nutrients and bacteria from swine CAFO lagoon water. Statistical analysis of data for pH, electrical conductivity (EC), inorganic and organic C, total N, water-soluble and total minerals (Ca, Cu, Fe, K, Mg, Mn, P, and Zn) and bacteria (Escherichia coli, enterococci, Clostridium perfringens, Campylobacter spp., Listeria spp., Salmonella spp., and staphylococci) showed that all differed significantly by dates of collection. During the irrigation season, levels of total N decreased by half and the N:P ratio changed from 9.7 to 2.8. Some seasonal differences were correlated with temperature. Total N and inorganic C increased below 19 °C, and decreased above 19 °C, consistent with summer increases in ammonia and greenhouse gas emissions. Water-soluble Cu, Fe, and Zn increased with higher summer temperatures while enterococci and zoonotic pathogens (Campylobacter, Listeria, and Salmonella) decreased. Although their populations changed seasonally, the zoonotic pathogens were present year-round. Increasing levels of E. coli were statistically correlated with increasing pH. Differences between depths were also found. Organic C, total nutrients (C, Ca, Cu, Fe, Mg, Mn, N, P, and Zn) and C. perfringens were higher in deeper samples, indicating stratification of these parameters. No statistical interactions were found between collection dates and depths. [Copyright &y& Elsevier]

Abstract: Effectiveness of surface-applied unincorporated broiler litter as a fertilizer relative to conventional inorganic fertilizers under no-till or conventional-till cotton (Gossypium hirsutum L.) production systems in the upland soils of the southern and southeastern USA is not well documented. The objectives of this research were to (1) test if broiler litter improves plant macronutrient (N, P, K, and Mg) nutrition of cotton above that of cotton fertilized with conventional inorganic fertilizers and (2) determine if lack of incorporating litter into the soil reduces macronutrient concentration in cotton plant parts in an upland soil considered marginal for cotton. Six treatments consisting of an unfertilized control, a fertilized standard (STD), two litter-only, and two litter plus inorganic N as urea–ammonium nitrate solution (UAN) were tested in two adjacent fields, one under no-till (NT) and the other under conventional-till (CT) systems. Litter alone, UAN, or a combination of litter plus UAN were applied to supply 101kgha−1 plant available N assuming nearly all of the UAN-N and 50% of the total litter N becomes plant available during the cotton growing season. Concentration of N, P, K, and Mg were measured in leaves, stems, and reproductive parts on three or four dates between early flowering and maturity. Cotton fertilized with the litter-only treatments always had less N concentration but greater P and K concentration in leaves, stems, and reproductive parts than cotton that received the STD treatment. Leaf and stem Mg concentration seems to depend on the N concentration in these plant parts. Lack of incorporating litter into the soil reduced N concentration in nearly all plant parts at all growth stages, suggesting some amount of the litter-derived N is lost due to lack of incorporation. Lack of incorporation also reduced leaf and stem Mg concentration, which seemed to be due to its reducing effect on N concentration. Unlike N and Mg, lack of incorporation did not consistently affect concentrations of P and K in all plant parts. Regardless of the incorporation treatment, fertilization with the litter-only treatments increased tissue P and K concentration and supported lint yield exceeding that of the STD without increasing tissue N concentration. [Copyright &y& Elsevier]