Assessment of Effects of Human Development on the Environment by Using System Dynamic Modeling Technique (SD): A Case Study of the Mkomazi Watershed (Pangani Basin) in Northeastern Tanzania

Abstract

This study analyzes land use changes due to human development in the Mkomazi Valley, Tanzania, and its impacts on nature using the SD–Modeling (System Dynamic modeling) technique. Ultimately this method relates environment and economy of society with regard to a seasonal rainfall–based agriculture practice and their harmonization with irrigation agriculture for development sustainability. VENSIM PLE (VENTANA SIMULATION ENVIRONMENT, PERSONAL LEARNING EDITION 2002) software, which simplified the assessment, was used to build a SD–model that accommodated changes in Population, Deforestation, Gross Domestic Product (GDP), and Basin Storage. Model results indicate groundwater behavior, deforestation, public opinion and decreased health of the farmers all relate to changes in land use (i.e., introduction of a rice development project) with its associated environment degradation, deforestation, and poverty due to deforestation. Moreover, these changes might be the cause of animal flight from the Mkomazi game reserve and an increase in human disease and deaths. Finally, it is concluded that uncontrolled human activities and behavior are the main causes of environmental degradation and therefore a brief summary is presented on challenges and opportunities for decision–makers on the sustainable development of the Mkomazi Valley.

Keywords:

• SD–model
• Mkomazi
• development
• VENSIM PLE
• population
• deforestation
• basin storage
• GDP.

ACKNOWLEDGMENTS

This publication was made possible after a fellowship award by UNESCO/P.R. China. Appreciation is also extended to colleagues at Huazhong University of Science and Technology–China for many valuable and encouraging comments.