| Popis: |
Controlling the total amount of water consumption is one application of the strictest water resources management strategy. In this study, it developed an approach which called the ET control theory to focus on how to reduce the real water consumption (invisible water). The ET control theory is what comparing the target ET with the present ET, if the present ET is more than the target ET; it means that the present consumed water is larger than the permitted. Otherwise, it implies that the water resources are surplus. The acquisition of the present ET has two methods, the calculation method and using the remote sensing ET. The target ET needed to consider the ecological water using of the whole basin, which normally is the average precipitation. The methods about reducing the ET include engineering practices and management practices. The results indicated that using the management practices which include adjusting the planting structure, changing the irrigation system, straw covering and plastic covering, to reduce the agriculture water consumption is the key of the ET control theory. |
