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This paper exposes the major results we have obtained in the dendrochronological and dendroecological analysis of Pinus canariensis that we have been developing in the Canary Islands since several years ago. We analyse the variability in tree ring formation based on a wide sampling from several natural pine forests. Applying several synchronisation techniques, recurrent dysfunctions in cambial activity resulting in total or partial missing rings have been established, and, when possible, local and individual chronologies have been built. We also analyse representative growing patterns and trends and we estimate the age structure in forest populations where dated sequences have been available. Finally, we estimate the dendrochronological age of certain monument trees by a new original method.

Aim and area of study: In the present paper we estimated the age of four monumental Pinus canariensis of Gran Canaria (Canary Islands, Spain) by means of tree-ring analysis. Many tree-ring series have been accurately studied and many missing rings have been determined.Material and methods: The trees were dead and the samples analysed were big disks. We measured numerous radii and crossdated the individual tree-ring series, paying particular attention to the existence and location of missing rings. We have distinguished between missing outer rings (MORs) and missing inner rings (MIRs) and analysed the possible causes of both.Main results: We determined an average of 8.8% total missing rings (MRs) for these long-lived trees, with a maximum of 96 MRs in a series of over 500. We have tried to establish a tree-ring chronology on Gran Canaria Island, also having the tree-ring series from Inagua site, but the long individual tree-ring series analysed do not crossdate between themResearch highlights: We consider the Canary pine a species hard to conducting dendroecological studies, especially if the samples come from managed old trees, in which a large amount of known and potentially unknown missing rings can hampered dating. Even knowing the difficulties involved in dendrochronological analyses of P. canariensis, we can confirm that it is a long-lived species, which can grow to over 500 years, and some of whose growth changes could be associated with certain historical and ecological events.

La pedología se encarga de estudiar la clasificación taxonómica permitiendo conocer el estado actual del suelo para evaluar y realizar recomendaciones adecuadas para su mejoramiento y su conservación. Esta investigación llevo a cabo un estudio pedológico en la Subcuenca del Río Zaratí (SRZ) para conocer la evolución, el desarrollo de los diferentes perfiles y analizar sus propiedades morfológicas, físicas, químicas y biológicas. La metodología utilizada se basó en la recolección de datos mediante observaciones de barreno a 120 cm de profundidad, muestreo de suelo en fosas de observación, pruebas de laboratorio y el posterior análisis de resultados. Se identificaron 14 perfiles modales o suelos representativos y se clasificaron según el sistema de Taxonomía de Suelos del Departamento de Agricultura de los Estados Unidos y se desarrolló la clasificación según la capacidad de uso de suelo. Los suelos en la SRZ son suelos antiguos, que presentan degradación natural y antrópica que afecta la calidad ambiental, la recarga acuífera y su rendimiento para actividades agrícolas. En la SRZ existen tres órdenes de suelos dominantes: Ultisoles, e Inceptisoles asociados a Entisoles, distribuidos en la parte baja, media y alta de la SRZ, respectivamente. Según la capacidad de uso de suelo se clasifican en tierras clase V y VI. Se recomienda implementar prácticas intensivas de manejo y conservación de suelos y agua como mecanización profunda, siembra de árboles y cultivos perennes que protejan el suelo del impacto directo de la lluvia para el control de la erosión y deterioro del suelo.