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Transforming the food-water-energy-land-economic nexus of plasticulture production through compact bed geometries النص الكامل
2017
Holt, Nathan | Shukla, S. | Hochmuth, George | Muñoz Carpena, Rafael | Ozores-Hampton, Monica
Raised-bed plasticulture, an intensive production system used around the world for growing high-value crops (e.g., fresh market vegetables), faces a water-food nexus that is actually a food-water-energy-land-economic nexus. Plasticulture represents a multibillion dollar facet of the United States crop production value annually and must become more efficient to be able to produce more on less land, reduce water demands, decrease impacts on surrounding environments, and be economically-competitive. Taller and narrower futuristic beds were designed with the goal of making plasticulture more sustainable by reducing input requirements and associated wastes (e.g., water, nutrients, pesticides, costs, plastics, energy), facilitating usage of modern technologies (e.g., drip-based fumigation), improving adaptability to a changing climate (e.g., flood protection), and increasing yield per unit area.Compact low-input beds were analyzed against conventional beds for the plasticulture production of tomato (Solanum lycopersicum), an economically-important crop, using a systems approach involving field measurements, vadose-zone modeling (HYDRUS), and production analysis. Three compact bed geometries, 61cm (width)× 25cm (height), 45cm× 30cm, 41cm× 30cm, were designed and evaluated against a conventional 76cm× 20cm bed. A two-season field study was conducted for tomato in the ecologically-sensitive and productive Everglades region of Florida. Compact beds did not statistically impact yield and were found to reduce: 1) production costs by $150–$450/ha; 2) leaching losses by up to 5% (1cm/ha water, 0.33kg/ha total nitrogen, 0.05kg/ha total phosphorus); 3) fumigant by up to 47% (48kg/ha); 4) plasticulture's carbon footprint by up to 10% (1711kg CO2-eq/ha) and plastic waste stream by up to 13% (27kg/ha); 5) flood risks and disease pressure by increasing field's soil water storage capacity by up to 33% (≈1cm); and 6) field runoff by 0.48–1.40cm (51–76%) based on HYDRUS model simulations of 10-year, 2-h storm events in other major tomato production regions of California and Virginia.Re-designing the bed geometries in plasticulture production systems to be more compact is an example of win-win production optimization not only for traditional farms in rural areas but also for urban and peri-urban farms which are located closer to city centers. Compact beds could enable more plants per unit area, thus requiring less land area for the same production. Needing less area facilitates urban and peri-urban farming where land values can be high. Urban and peri-urban farming has several benefits, including reductions in transportation energy as production is closer to market and the ability for city wastewater to be reused for irrigation instead of freshwater withdrawals. Compact beds allow plasticulture to have smaller water, chemical, energy, carbon, waste, and economic footprints without impacting production. Improving agricultural systems in this way could enhance economic and environmental viability, which is essential for a sustainable food-water-energy-land-economic nexus.
اظهر المزيد [+] اقل [-]Sustainability transitions of urban food-energy-water-waste infrastructure: A living laboratory approach for circular economy النص الكامل
2022
Valencia, Andrea | Zhang, Wei | Chang, Ni-Bin
Urban areas often face versatile stressors (e.g., food security, congestion, energy shortage, water pollution, water scarcity, waste management, and storm and flooding), requiring better resilient and sustainable infrastructure systems. A system dynamics model (SDM), explored for the urban region of Orlando, Florida, acts as a multi-agent model for portraying material and energy flows across the food, energy, water, and waste (FEWW) sectors to account for urban sustainability transitions. The interlinkages between the FEWW sectors in the SDM are formulated with multiple layers of dependencies and interconnections of the available resources and their external climatic, environmental, and socioeconomic drivers through four case studies (scenarios). The vital components in the integrated FEWW infrastructure system include urban agriculture associated with the East End Market Urban Farm; energy from the fuel-diverse Curtis H. Stanton Energy Center; reclaimed wastewater treated by the Eastern Water Reclamation Facility, the Water Conserv II Water Reclamation Facility, and stormwater reuse; and solid waste management and biogas generation from the Orange County Landfill. The four scenarios evaluated climate change impacts, policy instruments, and land use teleconnection for waste management in the FEWW nexus, demonstrating regional synergies among these components. The use of multicriteria decision-making coupled with cost-benefit-risk tradeoff analysis supported the selection of case 4 as the most appropriate option as it provided greater renewable energy production and stormwater reuse. The SDM graphic user interface aids in the visualization of the dynamics of the FEWW nexus framework, demonstrating the specific role of renewable energy harvesting for sustainably transitioning Orlando into a circular economy.
اظهر المزيد [+] اقل [-]Structural vulnerability to climate change in Bangladesh: a literature review. [Project report prepared by IWMI for the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) under the project "Water-related Interventions to Reduce Vulnerability to Climate Change: Do they Address the Structural Causes of Gendered Vulnerability in the IGP [Indo Gangetic Plains]"].
2014
Silva, Sanjiv de
Structural vulnerability to climate change in Bangladesh: a literature review. [Project report prepared by IWMI for the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) under the project "Water-related Interventions to Reduce Vulnerability to Climate Change: Do they Address the Structural Causes of Gendered Vulnerability in the IGP [Indo Gangetic Plains]"].
2012
Silva, Sanjiv de