1.1. INTRODUCTION Plastic covering, either framed or floating, is now used worldwide to protect crops from unfavorable growing conditions, such as severe weather and insects and birds. Protected cultivation in the broad sense, including mulching, has been widely spread by the innovation of plastic films. Paper, straw, and glass were the main materials used before the era of plastics. Utilization of plastics in agriculture started in the developed countries and is now spreading to the developing countries. Early utilization of plastic was in cold regions, and plastic was mainly used for protection from the cold. Now plastic is used also for protection from wind, insects and diseases. The use of covering techniques started with a simple system such as mulching, then row covers and small tunnels were developed, and finally plastic houses. Floating mulch was an exception to this sequence: it was introduced rather recently, although it is a simple structure. New development of functional and inexpensive films triggered widespread use of floating mulch. Table 1.1. The use a/plastic mulch in the world (after Jouet, 2001).
Auflage
Sprache
Verlagsort
Zielgruppe
Für höhere Schule und Studium
Für Beruf und Forschung
Professional/practitioner
Editions-Typ
Illustrationen
Maße
Höhe: 235 mm
Breite: 155 mm
Dicke: 12 mm
Gewicht
ISBN-13
978-1-4020-0846-7 (9781402008467)
DOI
10.1007/978-94-010-0583-8
Schweitzer Klassifikation
1. Introduction.- 1.1. Introduction.- 1.2. Europe and America.- 1.3. Asia.- 1.4. Africa and Middle Easy.- 1.5. Japan.- Problems.- 2. Definition of Covering and Properties of Covering Materials.- 2.1 Introduction.- 2.2 Mulching.- 2.3 Roe covers (Tunnels).- 2.4 Floating mulches (Floating row cover).- 2.5 Rain shelters.- 2.6 Unheated greenhouses.- 2.7 Covering materials.- Problems.- 3. Digital Simulation.- 3.1. Introduction.- 3.2. System dynamics.- 3.3. Simulation languages.- 3.4. Digital simulation by CSMP and MATLAB.- 3.5. Model structure and representation.- 3.6. A Model for temperature regimes in the soil (CUC01).- 3.7. Application to steady state models.- 3.8. More on MATLAB.- 3.9. SIMULINK.- Problems.- 4. Heat Balance of Bare Ground.- 4.1. Introduction.- 4.2. Convective heat transfer.- 4.3. A model with solar radiation and air temp. boundary condition (CUC02).- 4.4. Mass transfer.- 4.5. A model with latent heat transfer (CUC03).- 4.6. Radiation balance.- 4.7. Long wave radiation.- Problems.- 5. Solar Radiation Environment.- 5.1. Introduction.- 5.2. Units of radiation and light.- 5.3. Solar radiation properties of covering materials.- 5.4. Calcualtion of transmissivity (CUC04).- 5.5. Solar radiation.- 5.6. The sun's altitude and azimuth.- Problems.- 6. Temperature Environment Under Cover.- 6.1. Introduction.- 6.2. Effect of mulching.- 6.3. Temperature environment under row covers (CUC30).- 6.4. Double layer greenhouse model (CUC50).- 6.5. A pad and fan greenhouse model (CUC35).- Problems.- 7. CO2 Environment.- 7.1. Introduction.- 7.2. CO2 concentration in soil layer (CUC70).- 7.3. Program execution and output.- 7.4. CO2 concentration in a plastic house and ventilation.- 7.5. One dimensional interpolation.- Problems.- 8. Water and Water Vapor Environment.- 8.1.Introduction.- 8.2. Water and water vapor movement in soil.- 8.3. Water and heat balance in soil layer (CUC90).- 8.4. Interaction between water movement and heat flow.- Problems.- 9. Control Function.- 9.1. Introduction.- 9.2. System response.- 9.3. PID control.- 9.4. Temperature control logic (CUC120).- 9.5. Feedback vs. feedforward control.- Problems.- 10. Plant Response to the Environment.- 10.1. Introduction.- 10.2. Plant photosynthesis and respiration.- 10.3. Energy balance of a plant leaf.- 10.4. Stomata resistance of plant (CUC151).- 10.5. Plant growth model.- Problems.- References.
