748 research outputs found
Fine tuning deep phosphorus and potassium management
Take home message
• The re-application interval for the deep placement of phosphorus (P) and potassium (K) will depend on the most limiting nutrient and crop type
• Residual effects of deep P bands applied 5 years previously were still evident in the 2019 chickpea crop on a site with very low soil P status, with yield increases of 500 (20P) to 1000 (40P) kg/ha compared to sites where no deep P had been applied
• However, yield increases of a further 900 kg/ha were recorded when a 2nd deep P application was made during the preceding fallow, clearly augmenting the P supply from the residual P bands
• In contrast, there was no evidence of any residual benefits from deep K bands applied 3-5 years ago shown in chickpea crops at two low K sites, but yield increases of 500 kg/ha were recorded when K was re-applied during the preceding fallow
• Potassium-limited sites may require shorter re-application intervals than sites where the main limit is phosphorus
• Legume grain crops export more K/t grain than cereals, but cereals can quickly redistribute deep K back to surface soil layers in stubbles, due to their low rates of removal
Nutritional strategies to support productive farming systems
Take home messages
• A critical success factor for cropping systems that rely heavily on stored soil water is co-location of plant nutrients with moist soil and active roots
• Our current fertiliser management practices need refinement, with low efficiency of fertiliser recovery often associated with nutrients and water being in different parts of the soil profile
• There needs to be greater consideration of placement and timing of fertiliser applications to improve fertiliser nutrient recovery
• Declining native fertility reserves means more complex fertiliser combinations will be needed to meet crop demand
Strategies to improve efficiency of use of applied N, P and K fertiliser in Central Queensland
Take home messages
• Available moisture has been the main limit to productivity in recent seasons but using that water efficiently to produce harvestable yield is impossible without adequate nutrients
• The background nutrient status of soils in Central Qld is variable, but there is an increasing reliance on fertilisers to meet the demands of both cereal grains and pulses
• With more $/ha invested in fertilisers, comes a need for efficient use of that fertiliser to ensure there is a return on that investment
• A common cause of low efficiency of fertiliser recovery in cereal and legume crops is that nutrients and water are increasingly located in different parts of the soil profile
• There needs to be greater consideration of fertiliser placement, product and timing to improve fertiliser nutrient recovery, and strategies need to be based on a solid understanding of the interactions between crop root systems, soil characteristics and nutrient dynamics against a background of variable seasonal moisture availability
Seasonal Abudance of Arthropod Populations on Selected Soybean Variteties Grown in Early Season Production Systems in Louisiana (Bulletin #860)
The data presented in this report were collected by entomologists to provide Louisiana soybean producers with information on insect management practices that may be required as they select the soybean maturity group that best fits their production systems.https://digitalcommons.lsu.edu/agcenter_bulletins/1044/thumbnail.jp
Adam Smith’s Green Thumb and Malthus’ Three Horsemen: Cautionary tales from classical political economy
This essay identifies a contradiction between the flourishing interest in the environmental economics of the classical period and a lack of critical parsing of the works of its leading representatives. Its focus is the work of Adam Smith and Thomas Malthus. It offers a critical analysis of their contribution to environmental thought and surveys the work of their contemporary devotees. It scrutinizes Smith's contribution to what Karl Polanyi termed the "economistic fallacy," as well as his defenses of class hierarchy, the "growth imperative" and consumerism. It subjects to critical appraisal Malthus's enthusiasm for private property and the market system, and his opposition to market regulation. While Malthus's principal attraction to ecological economists lies in his having allegedly broadened the scope of economics, and in his narrative of scarcity, this article shows that he, in fact, narrowed the scope of the discipline and conceptualized scarcity in a reified and pseudo-scientific way
The science case and mission concept for the Single Aperture Far-Infrared (SAFIR) Observatory
SAFIR is a large (10 m-class), cold (4-10 K) space telescope for wavelengths between 20 microns and 1 mm. It will provide sensitivity a factor of a hundred or more greater than that of Spitzer and Herschel, leveraging their capabilities and building on their scientific legacies. Covering this scientifically critical wavelength regime, it will complement the expected wavelength performance of the future flagship endeavors JWST and ALMA. This vision mission will probe the origin of stars and galaxies in the early universe, and explore the formation of solar systems around nearby young stars. Endorsed as a priority by the Decadal Study and successive OSS roadmaps, SAFIR represents a huge science need that is matched by promising and innovative technologies that will allow us to satisfy it. In exercising those technologies it will create the path for future infrared missions. This paper reviews the scientific goals of the mission and promising approaches for its architecture, and considers remaining technological hurdles. We review how SAFIR responds to the scientific challenges in the OSS Strategic Plan, and how the observatory can be brought within technological reach
Pennsylvania Folklife Vol. 25, Folk Festival Supplement
• Quilts, Quilts, Quilts • America\u27s Heritage is Endowed with Contributions of the Pennsylvania Dutch • The Hospitality Tent: H is for Help - That\u27s What it\u27s all About • Pottery: A Folk Art Expressing the Most in Simplest Terms • It Never Rains on our Parade - On the Fourth of July • Vegetable Dyeing at the Kutztown Folk Festival • Festival Focus • Folk Festival Program • Festival Foods: The Original Touch of the Dutch • Ursinus College Studies at the Festival • Behind the Scenes of We Like Our Country, But We Love Our God • Reverse Glass Tinsel Painting • Tin, Tole and Independencehttps://digitalcommons.ursinus.edu/pafolklifemag/1069/thumbnail.jp
Production of nano hydroxyapatite and Mg-Whitlockite from biowaste-derived products via continuous flow hydrothermal synthesis : a step towards circular economy
Biowastes from agriculture, sewage, household wastes, and industries comprise promising resources to produce biomaterials while reducing adverse environmental effects. This study focused on utilising waste-derived materials (i.e., eggshells as a calcium source, struvite as a phosphate source, and CH3COOH as dissolution media) to produce value-added products (i.e., calcium phosphates (CaPs) derived from biomaterials) using a continuous flow hydrothermal synthesis route. The prepared materials were characterised via XRD, FEG-SEM, EDX, FTIR, and TEM analysis. Magnesium whitlockite (Mg-WH) and hydroxyapatite (HA) were produced by single-phase or biphasic CaPs by reacting struvite with either calcium nitrate tetrahydrate or an eggshell solution at 200 °C and 350 °C. Rhombohedral-shaped Mg-WH (23–720 nm) along with tube (50–290 nm diameter, 20–71 nm thickness) and/or ellipsoidal morphologies of HA (273–522 nm width) were observed at 350 °C using HNO3 or CH3COOH to prepare the eggshell and struvite solutions, and NH4OH was used as the pH buffer. The Ca/P (atomic%) ratios obtained ranged between 1.3 and 1.7, indicating the formation of Mg-WH and HA. This study showed that eggshells and struvite usage, along with CH3COOH, are promising resources as potential sustainable precursors and dissolution media, respectively, to produce CaPs with varying morphologies
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