A research was carried out at the Experimental Station of the University of Concepcion in Chillan, to determine: a) The water requirements for highbush blueberries during their first year after plantation. b) The growth response obtained from highbush blueberries, when watered by microjet or by drip irrigation with increasing levels of water reposition. c) The crop coefficients Kc recommended. The statistical experimental design was a completely random block, in a factorial arrangement with two treatments, four subtreatments and four replications. The plantation of the Bluetta variety was made with plants brought from shading, in October 1990. The planting was done at 1.5 by 3.0 meters. The treatments consisted of two irrigation methods: microjet and drip. The subtreatments consisted in the reposition of 15%, 30%, 45% and 80% of the potential evapotranspiration, calculated on the basis of a class A evaporation pan, located at the site of the experiment. The main conclusions of this research are: 1. The plants that were drip irrigated grew more than those irrigated by microjet. 2. In microjet irrigation, the best growth was obtained with a level of reposition of 45% of the potential evapotranspiration. Levels around 60% of the ETpot were excessive and detrimental to growth. 3. In drip irrigation, the best growth was obtained with a level of reposition of 60% of the potential evapotranspiration with the possibility of obtaining an even better growth if more water were applied. 4. The highest water demand occurs in February with a real evapotranspiration of 15.24 liters per plant/day for microjet irrigation and 18.62 for drip irrigation. The maximum crop coefficient Kc for February were 0.556 for microjet irrigation and 0.679 for drip irrigation.

Dentro de los trabajos realizados por el Centro Control Contaminación del Pacífico (CCCP) surge, durante el año 1983, el Programa Bioecológico Región IV Zona III; cuyo principal objetivo es contribuir al conocimiento de las características de los diferentes ecosistemas del Litoral Pacífico Colombiano y su utilización racional de recursos orientando las actividades de investigación hacia la determinación de las posibles fuentes de contaminación, así como las propiedades físico-químicas y la calidad de las aguas, con el fin de proteger el medio, los recursos y la gestión de estos últimos. Del mismo modo, pretende recalcar la importancia de las investigaciones pluridisciplinarias a desarrollar en el futuro con base en el inventario que se obtenga de flora, fauna y agentes contaminantes es durante la realización de esta investigación. El presente es un informe que recopila las actividades y resultados obtenidos durante la ejecución de este programa, cumpliendo así con un buen número de los objetivos propuestos por él. Las actividades constan de muestreos de agua, sedimentos y organismos y de análisis en el laboratorio, del material colectado, para obtener los datos adecuados según el tipo de resultado perseguido. Se realizan estudios de calidad de agua, biológicos y geomorfológicos, cuyos resultados son presentados a lo largo del presente informe. | Within the work realized by the CCCP, in 1983 was created the IV Región III Zone Bioecological programe which main aim is to contribute to the Understanding of the severl Colombian Pacific Littoral ecosystems and their rational use. In order to reach such aim the activities have been oriented towards determination of possible pollution sources, physico-chemical properties and quality water to be able to evaluate the stage of natural resources, their protection and possible explotation. The program emphases the importance of future plury disciplinary researches which will be based on the flora, fauna and pollutant agent inventory obtained during the program performance. This report compile activities and results obtair ed during the program execution. Collected material of water, sediments and organisms was analyzed. | Published

Se realizo un experimento en invernadero con el objetivo de determinar la funcion en respuesta del arroz (Oryza sativa L.) al potencial de presion del agua en el suelo en tres etapas fenologicas. El factor estudiado fue el potencial de presion del agua en el suelo para cada etapa, en cuatro niveles: 0.0, -2.0, -4.0 y -6.0 m de columna de agua, medido con tensiometros instalados a 15 cm de profundidad. El diseno de tratamientos fue de acuerdo con un San Cristobal, en un diseno experimental completamente al azar. Las variables medidas fueron rendimiento, numero de hijos y peso por espiga. Se determino la funcion de respuesta para cada caso, a partir de la cual se obtuvo el potencial de presion del agua en el suelo que optimiza el rendimiento, siendo de -1.59 m, -0.76 m y -1.15 m en las etapas vegetativa, reproductiva y maduracion, respectivamente. Se observo que la etapa critica, en cuanto al suministro de agua, es la reproductiva, cuando se definen los componentes del rendimiento. En todos los casos el rendimiento supero a la media regional, asi como al testigo, que siempre estuvo inundado. | A greenhouse experiment was carried out to determine the response function of rice (Oryza sativa L.) to soil water pressure potential in three growth stages. The factor studied was soil water pressure potential at four levels of 0.0 m, -2.0 m, -4.0 m and -6.0 m of water column. The treatments were deviced according to a San Cristobal design, using a completely randomized design. The variables measured were crop production, number of suckers, and tussel weight. A response function was determined to estimate the water pressure potential values that optimize the yield. The results shown estimation of -1.59 m, -0.76 m and -1.15 m for the vegetative, reproductive and the maturity stages, respectively. Water supply became critical during the reproductive stage, when grain originates. Yield exceeded the previously recorded regional mean, as well as the yield recorded for the treatment plot which remained flooded most of the time.