Page 6 - Biosystems Engineering

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3.6.2 Factors Affecting Soil Erosion and
Sediment Yield . . . . . . . . . . . . . . . . . . . 112
3.6.3 Types of Soil Erosion . . . . . . . . . . . . . . 113
3.6.4 Universal Soil Loss Equation . . . . . . . 114
3.7 Best Management Practices . . . . . . . . . . . . . . . 117
3.7.1 Commonly Used BMPs . . . . . . . . . . . . 118
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

4 Models for Heat Transfer in Heated
Substrates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
4.1 Heat Transfer in Soils . . . . . . . . . . . . . . . . . . . . 125
4.1.1 The Soil Thermal Regime . . . . . . . . . . 125
4.1.2 Factors Affecting Soil
Temperature . . . . . . . . . . . . . . . . . . . . . 126
4.2 Soil Thermal Properties . . . . . . . . . . . . . . . . . . 128
4.2.1 Specific Heat or Heat Capacity . . . . . 128

4.2.2 Effective Thermal Conductivity . . . . 128
4.2.3 Effective Thermal Diffusivity . . . . . . . 130
4.2.4 Determination of Soil Thermal
Properties . . . . . . . . . . . . . . . . . . . . . . . 130
4.3 Models for Predicting Soil Temperature . . . . 139
4.3.1 Applications of the Models for
Predicting Soil Temperature . . . . . . . 139
4.3.2 Methods Used to Build Models for
Predicting Soil Temperature . . . . . . . 142
4.4 Greenhouse Substrate Heating . . . . . . . . . . . . 146
4.5 Models for Predicting Temperature in
Heated Substrates . . . . . . . . . . . . . . . . . . . . . . . 148
4.6 An Analysis of Electric Cable Heating
Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160

5 Geographic Information System-Based Watershed
Modeling Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
5.2 Watershed Models . . . . . . . . . . . . . . . . . . . . . . . 170
5.2.1 Need for Watershed Models . . . . . . . 170
5.2.2 Origin of Watershed Models . . . . . . . 171
5.2.3 Characterization of Watershed
Models . . . . . . . . . . . . . . . . . . . . . . . . . . 171
5.2.4 Important Components of Watershed
Models . . . . . . . . . . . . . . . . . . . . . . . . . . 172
5.2.5 Examples of Commonly Used
Watershed Models . . . . . . . . . . . . . . . . 175