Coupling DSSAT and HYDRUS-1D for simulations of soil water dynamics in the soil-plant-atmosphere system

Abstract Accurate estimation of the soil water balance of the soil-plant-atmosphere system is key to determining the availability of water resources and their optimal management. Evapotranspiration and leaching are the main sinks of water from the system affecting soil water status and hence crop yield. The accuracy of soil water content and evapotranspiration simulations affects crop yield simulations as well. DSSAT is a suite of field-scale, process-based crop models to simulate crop growth and development. A “tipping bucket” water balance approach is currently used in DSSAT for soil hydrologic and water redistribution processes. By comparison, HYDRUS-1D is a hydrological model to simulate water flow in soils using numerical solutions of the Richards equation, but its approach to crop-related process modeling is rather limited. Both DSSAT and HYDRUS-1D have been widely used and tested in their separate areas of use. The objectives of our study were: (1) to couple HYDRUS-1D with DSSAT to simulate soil water dynamics, crop growth and yield, (2) to evaluate the coupled model using field experimental datasets distributed with DSSAT for different environments, and (3) to compare HYDRUS-1D simulations with those of the tipping bucket approach using the same datasets. Modularity in the software design of both DSSAT and HYDRUS-1D made it easy to couple the two models. The pairing provided the DSSAT interface an ability to use both the tipping bucket and HYDRUS-1D simulation approaches. The two approaches were evaluated in terms of their ability to estimate the soil water balance, especially soil water contents and evapotranspiration rates. Values of the d index for volumetric water contents were 0.9 and 0.8 for the original and coupled models, respectively. Comparisons of simulations for the pod mass for four soybean and four peanut treatments showed relatively high d index values for both models (0.94–0.99)

Evaluating the Effect of Local Historic Preservation and Climate Change Action Policy on the Promotion of Operating Energy Efficiency in Historic Buildings

The built environment offers significant potential for achieving climate change mitigation goals. Located within these goals is the strategy to drastically reduce of greenhouse gas emissions through renovating and reusing existing buildings. As a small portion of existing buildings, designated historic buildings play an important role in reducing emissions in urban environments in addition to their role of providing architectural and cultural value. The 2015 Paris Climate Agreement marked an urgent change in urban policy to target greenhouse gas emissions, with fast approaching deadlines. As preservation expands the number of buildings designated on local, state, and federally historic building lists, the number of existing buildings deemed historic will continue to grow, creating the need for historic buildings to contribute meaningfully to energy efficiency improvements and climate change mitigation goals. Operating energy efficiency fits into the larger climate change narrative as an opportunity to reduce long-term building energy consumption and switch to renewable energy sources. Preservationists already use historic building operating energy consumption as an advocacy approach, citing the building’s inherent energy saving features alongside embodied energy saved and sustainable land use opportunities. However, historic buildings consist of a diverse group of buildings that do not necessarily feature inherently sustainable design features. Additionally, current policy frameworks do not back up these claims, often incentivizing historic building reuse projects through ease in energy regulations, specifically energy conservation code exemptions. Conflicts exist among preservationists surrounding historic buildings and energy efficiency due to the potential negative impacts energy retrofits could have on architectural and material character, and the debate has remained remarkably stagnant for the past forty years. Through close evaluation of local regulatory conditions, climate change action initiatives, and project level decision-making, this thesis defines opportunities for changes in the regulatory environment to improve the promotion of operating energy efficiency in historic buildings. By forging the conversation between regulatory officials, historic preservationists, building professionals, and sustainability advocates, this thesis supports further exploration of how historic preservation can serve the present-day need of climate change mitigation

IXIM: A new maize simulation model for DSSAT v4.5.

The Decision Support System for Agrotechnology Transfer (DSSAT) is a suite of crop simulation models and associated tools for simulating growth, development, and yield of 25 crops. The maize simulation model in DSSAT is CSM-CERES, the modular version of CERES-Maize, which was first published in 1986. The newest release of DSSAT, version 4.5, provides users with the opportunity to run an alternative maize simulation model. IXIM (eeh-sheem), the Mayan language for maize, is a new, more mechanistic, maize simulation model fully compatible with DSSAT. The purpose of this work is to compare seasonal simulations of maize growth and N uptake using CSM-CERES and IXIM

Effects of substrate and co-culture on neural progenitor cell differentiation

For stem and progenitor cells to become clinically useful, the factors that influence their differentiation must be better understood. The interaction between progenitor cells and their environment is thought to be one of the main influences on differentiation. This thesis examines the effects of media conditioned by primary astrocytes and extracellular matrix protein surface coatings on the differentiation of neural progenitor cells

The Evolution of Large Pleasure Vessel Towards a Green Future

The future of transportation means is quickly moving towards green solutions in order to reduce the emission of COx and SOx firstly and, secondly, to progressively abandon the fossil fuels. In this perspective, alternative propulsion such as fully electric engine, biofuels, hydrogen, LNG are now largely used in the automotive field and for mass transportation means. The naval field is now moving on the same trend by using hybrid and fully electric engine especially for pleasure vessels, where the relatively small engine power allows the installation of battery stacks onboard without adding unreasonable weight for only few navigation miles. In this paper, the transformation of a traditional pleasure vessel towards a new hybrid version is proposed; after a more comprehensive view of the modifications that are necessary to install hybrid engine and battery onboard, highlighting all the critical aspects of these new design, a FE numerical analysis of the basement of electric variable speed generators is presented