Evaluation net greenhouses for tomato production in tropics [Elektronische Ressource] / von Harmanto

Harmanto

Informations

• Publié par: gottfried_wilhelm_leibniz_universitat_hannover
• Publié le: 01 janvier 2006
• Nombre de lectures: 18
• Langue: English
• Poids de l'ouvrage: 1 Mo

Extrait

Evaluation of net greenhouses for tomato
production in the tropics







Der Naturwissenschaftlichen Fakultät

Der Universität Hannover

Zur Erlangung des akademischen Grades eines

Doktors der Gartenbauwissenschaften

- Dr. rer. hort. -




genehmigte




Dissertation






von

Ir. M., Eng. Harmanto

geboren am 23. 11. 1967 in Wonogiri, Indonesia

2006
































Referent: Prof. Dr. rer. hort. habil. Hans-J. Tantau

Korreferent: Prof. Dr. Vilas M. Salokhe


Tag der Promotion: 31.01.2006


Contents

List of Figures.........................................................................................................vi
List of Tables..........................................................................................................ix
List of Symbols....................................................................................................... x
Summary..............................................................................................................xiv
Zusammenfassung...............................................................................................xvi
1. Introduction 1
2. Literature Review 4
2.1 Greenhouse design approach for tropical region.......................................... 4
2.2 Type of insect-proof net for greenhouse ....................................................... 6
2.3 Previous works on insect-proof net used for greenhouse ........................... 10
2.4 Type and design of greenhouse ventilation openings................................. 13
2.5 Air exchange rate........................................................................................ 16
2.5.1 Measurement of air exchange rate 16
2.5.2 Estimating air exchange rate based on wind speed and chimney
effect.................................................................................................. 19
2.5.3 Simulation and Modelling to predict air exchange rate......................... 21
3. Objectives and Hypothesis............................................................................... 25
3.1 Objectives................................................................................................... 25
3.2 Hypothesis 26
4. Material and Methods....................................................................................... 27
4.1 General....................................................................................................... 27
4.1.1 Experimental site and greenhouse description..................................... 27
4.1.2 Instrumentation for measuring climate ................................................. 29
4.1.3 Crop cultivation and irrigation system................................................... 30
4.1.4 Measuring crop performance................................................................ 30
4.1.5 Measuring crop transpiration rate......................................................... 31
4.1.6 Measuring insect pest infestation (abundances) in the greenhouse..... 32
4.2 Performance of the adapted greenhouse incorporated with screen
ventilating system ...................................................................................... 33
4.2.1 Experimental set-up ............................................................................. 34
4.2.2 Data collection and analysis................................................................. 35
4.3 Simulation and modelling to predict air exchange rate and internal
microclimate............................................................................................... 35 iv
4.3.1 Measuring air exchange rate................................................................ 36
4.3.1.1 Water vapour balance method .......................................................... 36
4.3.1.2 Energy balance method .................................................................... 38
4.3.2 Development of a model to predict air exchange rate .......................... 41
4.3.3 Development of models to predict internal microclimate ...................... 43
4.3.4 Models validation.................................................................................. 46
4.4 Determination of a minimum size of ventilation openings ........................... 47
4.4.1 Experimental greenhouse 47
4.4.2 Data measurement and analysis.......................................................... 50
4.4.2.1 Air exchange rates and humidity measurements............................... 50
4.4.2.2 Air temperature rise measurements .................................................. 50
4.5 Evaluation on the effectiveness of exhaust fans used on the adapted
greenhouse................................................................................................ 51
5. Results ............................................................................................................. 53
5.1 Performance of the adapted greenhouse ................................................... 53
5.1.1 Microclimate and air exchange rate at different seasons of the year.... 53
5.1.2 Effect of net sizes on air exchange rates and microclimate.................. 59
5.1.3 Effect of mesh-sizes of nets on plant growth and yield......................... 64
5.1.4 Effect of mesh-sizes of nets on biological plant protection ................... 70
5.1.5 Water requirement (evapotranspiration) in greenhouse ....................... 73
5.2 Simulation and modelling to predict air exchange rate and internal
microclimate............................................................................................... 75
5.2.1 Air exchange rates along the experimental period of time.................... 75
5.2.2 Development of a model for predicting air exchange rate 77
5.2.3 Development of greenhouse models to predict internal microclimate .. 81
5.2.4 Influence of external wind speed and buoyancy effect on air
exchange rate.................................................................................... 87
5.3 Study on ventilation configuration of adapted greenhouse ......................... 90
5.3.1 Effect of vent opening arrangements on greenhouse microclimate...... 90
5.3.2 Effect of vent opening arrangements on crop transpiration rate........... 95
5.3.3 Effect of vent opening arrangements on air exchange rates ................ 96
5.3.4 Optimum configuration of vent opening for adapted greenhouse....... 104
5.4 Effectiveness of exhaust fans used on adapted greenhouse.................... 106
5.4.1 Performance of adapted greenhouse with exhaust fans operating
under empty condition ..................................................................... 106 v
5.4.2 Effect of operated exhaust fans on microclimate and air exchange
rate in fully tomato-grown greenhouse ............................................ 110
6. Discussions .................................................................................................... 115
6.1 General..................................................................................................... 115
6.2 Performance of adapted greenhouse in tropics ........................................ 117
6.3 Simulation and modelling in a naturally ventilated greenhouse in the
humid tropics ........................................................................................... 125
6.4 Optimum arrangement of vent opening ratio............................................. 131
7. Conclusions.................................................................................................... 134
8. Recommendations ......................................................................................... 137
References......................................................................................................... 138
Appendixes......................................................................................................... 143
Acknowledgements ............................................................................................ 147 vi
List of Figures
Figure 4.1: Isometric view of net greenhouse with different mesh sizes as
cladding material as well as roof opening.................................................. 28
Figure 4.2: Measurement of crop transpiration rate in greenhouse...................... 32
Figure 4.3: Placements of blue and yellow sticky traps in each greenhouse to
monitor insect’s infestation to the tomato crops......................................... 33
Figure 4.4: Heat and mass fluxes occurring in such a greenhouse and
measuring some climatic parameters to estimate air exchange rate ......... 39
Figure 4.5: Simplified heat and mass fluxes occurring in greenhouse assumed
as a solar collector to predict internal microclimate ................................... 43
Figure 4.6. Arrangements on closing particular vent opening of nets with an
UV-stabilized plastic film to determine a minimum size of vent ratio ......... 49