FOREWORD

An intensive academic programme, followed by one hundred and seventy-one scientists from twenty-three different countries, was developed from 23 to 27 November 1992, including technical visits on 25 November. The programme was structured on the following sessions:

1. Environmental Impact
2. Crop Water Relations
3. Water Management

Two introductory lectures were presented during session A:

"Irrigation in the Spanish National Hydrological Plan" by Dr. A. Baltanás. The speaker described the framework which may condition the development and rationalization of irrigation in accordance with the imminent legislation to be introduced on this matter in Spain.

"Ground water contamination concerns in horticultural production systems" by Dr. K. Tanji, who focused on the external contamination of ground water, comparing the effects of pesticides and nitrates.

Under this topic seven papers and five posters were presented.

Session B was introduced by a paper dealing with ecophysiological aspects related to irrigation scheduling: "Growth and productivity of crops in relation to water status". This lecture was presented by Dr. T.C. Hsiao.

The following presentations dealt with crop responses to different irrigation treatments and, in particular, with root signals for growth control, as well as with morphological alterations in the stem and canopy architecture, water potential, gas exchange, and variable application of nitrogen.

Session C was introduced by the lecture of the following three papers:

"New approaches to estimating crop evapotranspiration" by Dr. R. Allen who justified the use of reference evapotranspiration and crop coefficients, and the only relative interest of the Penman- Monteith method.

Dr. C. Stanghellini revised in her lecture "Evapotranspiration in greenhouses with special reference to Mediterranean conditions" the effects of the four main ambient factors: light, CO2, temperature and humidity.

Lastly Dr. F. Zazueta talked about "New technologies in the management of microirrigation systems" revising the application of computers and microelectronics to irrigation systems management.

This last session was the one with the highest number of contributions, namely a total of thirty-four (twenty-four orally presented papers and ten posters). The topics dealt with during this session reached from the prediction of real water consumption at micro and regional scales to the use of water content sensors and vegetative and reproductive responses of crops to irrigation. Continuous and surged surface irrigation, as well as sprinkler irrigation for climatic control and geotextile pipes for drip irrigation were other subjects.

The technical tours offered two alternatives: a visit to the natural maritime-terrestrial park of Cabo de Gata or an informative tour on irrigation systems offering again two possibilities: "traditional systems of historic interest" or "systems for intensive cropping in plastic greenhouses".

I hope the participants will have been satisfied thanks to the variety of natural and transformed conditions existing in Almería: the former being of interest because of their peculiarity and the latter, especially the ones related to irrigation, in view of the application of the most ancient and widest fan of possibilities developed in the Occidental World, from the prehistoric irrigation method based on old earth diversion canals ("boqueras de cañon") to high technology used for intensive cropping under plastic.

Finally I wish to express my gratitude to the sponsors and collaborating entities, to the Organizing and Editorial Committees, and especially to the Foundation for Agricultural Research in the Province of Almeria (F.I.A.P.A.) who took a decisive role in the celebration of this Symposium.

Dr. J. López-Gálvez
Experimental Station "Las Palmerillas"
Caja Rural de Almería
Almería (Spain)