Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Growth and survival in Quercus ilex L. seedlings after irrigation and artificial shading on Mediterranean set-aside agricultural land. | Ann. Sci. For. 55 1998 801-807 Inra Elsevier Paris 801 Original article Growth and survival in Quercus ilex L. seedlings after irrigation and artificial shading on Mediterranean set-aside agricultural land José M. Rey Benayas Ecologia facultad de Cicncias Universidad de Alcala 28871 Alcala de Henarcs Spain Received 14 May 1997 accepted 26 November 1997 Abstract - Considerable quantities of agricultural land are being transformed into forested lands in . countries. To assess afforestation practice we analyzed the growth and survival of 800 Quer-cus ilex sp. ballota seedlings in set-aside agricultural land under semi-arid Mediterranean climate conditions in central Spain. The survival and growth of the seedlings were monitored for 3 years after planting with an experimental design that included all four combinations of i irrigation or no irrigation during the dry season and ii artificial shading or no shading. Significant differences in survival and growth height stem diameter and crown projected area were found among treatments. Survival was lowest 53 in the control plots and very similar around 93 for the irrigation shade and combined treatments. Most of the mortality occurred after the first dry season. The high survival rate in irrigated but not shaded plots coincided with a thick layer of the weed Amaranthus retroflexus L in the first dry season . Seedling growth was greatest on average under irrigation and shade conditions. Shade was found to have a significant effect for all growth measurements while irrigation alone only affected stem diameter growth and crown projected area in interaction with shade. Growth measurements were correlated to microclimatic conditions in the plots as measured by the amounts of water and actual evapotranspiration. We conclude that the attenuation of summer stress must be considered in the early stages of successful plantation practice of set-aside agricultural land in a dry environment. Inra Elsevier Paris. agricultural land .
