Advancing Land Change Modeling


Book Description

People are constantly changing the land surface through construction, agriculture, energy production, and other activities. Changes both in how land is used by people (land use) and in the vegetation, rock, buildings, and other physical material that cover the Earth's surface (land cover) can be described and future land change can be projected using land-change models (LCMs). LCMs are a key means for understanding how humans are reshaping the Earth's surface in the past and present, for forecasting future landscape conditions, and for developing policies to manage our use of resources and the environment at scales ranging from an individual parcel of land in a city to vast expanses of forests around the world. Advancing Land Change Modeling: Opportunities and Research Requirements describes various LCM approaches, suggests guidance for their appropriate application, and makes recommendations to improve the integration of observation strategies into the models. This report provides a summary and evaluation of several modeling approaches, and their theoretical and empirical underpinnings, relative to complex land-change dynamics and processes, and identifies several opportunities for further advancing the science, data, and cyberinfrastructure involved in the LCM enterprise. Because of the numerous models available, the report focuses on describing the categories of approaches used along with selected examples, rather than providing a review of specific models. Additionally, because all modeling approaches have relative strengths and weaknesses, the report compares these relative to different purposes. Advancing Land Change Modeling's recommendations for assessment of future data and research needs will enable model outputs to better assist the science, policy, and decisionsupport communities.




Economic Models of Tropical Deforestation: A Review


Book Description

Types of economic deforestation models. Household and firm-level models. Regional-level models. National and macro-level models. Priority areas for future research.




Agricultural Household Models


Book Description

This book presents the basic model of an agricultural household that underlies most of the case studies undertaken so far. The model assumes that households are price-takers and is therefore recursive. The decisions modeled include those affecting production and the demand for inputs and those affecting consumption and the supply of labor. Comparative results on selected elasticities are presented for a number of economies. The empirical significance of the approach is demonstrated in a comparison of models that treat production and consumption decisions separately and those in which the decisionmaking process is recursive. The book summarizes the implications of agricultural pricing policy for the welfare of farm households, marketed surplus, the demand for nonagricultural goods and services, the rural labor market, budget revenues, and foreign exchange earnings. In addition, it is shown that the basic model can be extended in order to explore the effects of government policy on crop composition, nutritional status, health, saving, and investment and to provide a more comprehensive analysis of the effects on budget revenues and foreign exchange earnings. Methodological topics, primarily the data requirements of the basic model and its extensions, along with aggregation, market interaction, uncertainty, and market imperfections are discussed. The most important methodological issues - the question of the recursive property of these models - is also discussed.




ORYZA2000


Book Description




Advances in Crop Modelling for a Sustainable Agriculture


Book Description

Crop modelling has huge potential to improve decision making in farming. This collection reviews advances in next-generation models focused on user needs at the whole farm system and landscape scale.










Applied Groundwater Modeling


Book Description

This second edition is extensively revised throughout with expanded discussion of modeling fundamentals and coverage of advances in model calibration and uncertainty analysis that are revolutionizing the science of groundwater modeling. The text is intended for undergraduate and graduate level courses in applied groundwater modeling and as a comprehensive reference for environmental consultants and scientists/engineers in industry and governmental agencies. - Explains how to formulate a conceptual model of a groundwater system and translate it into a numerical model - Demonstrates how modeling concepts, including boundary conditions, are implemented in two groundwater flow codes-- MODFLOW (for finite differences) and FEFLOW (for finite elements) - Discusses particle tracking methods and codes for flowpath analysis and advective transport of contaminants - Summarizes parameter estimation and uncertainty analysis approaches using the code PEST to illustrate how concepts are implemented - Discusses modeling ethics and preparation of the modeling report - Includes Boxes that amplify and supplement topics covered in the text - Each chapter presents lists of common modeling errors and problem sets that illustrate concepts