TAILIEUCHUNG - Báo cáo lâm nghiệp: "Interactive effects of phosphorus and light availability on early growth of maritime pine seedlings"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp Original article đề tài:"Interactive effects of phosphorus and light availability on early growth of maritime pine seedlings" | Ann. For. Sci. 62 2005 575-583 INRA EDP Sciences 2005 DOI forest 2005050 575 Original article Interactive effects of phosphorus and light availability on early growth of maritime pine seedlings Alissar CHEAiBa Alain MOLLIERa Stéphane THUNOTa Catherine LAMBROTb Sylvain PELLERINa Denis LOUSTAUb a INRA UMR TCEM Transfert Sol-Plante et Cycle des Éléments Minéraux dans les Écosystèmes Cultivés 71 avenue Edouard-Bourlaux Bp 81 33883 Villenave d Ornon Cedex France b INRA Unité EPHYSE Écologie Fonctionnelle et Physique de l Environnement 69 route d Arcachon 33612 Gazinet France Received 2 June 2004 accepted 29 April 2005 Abstract - We examined the response of early growth of maritime pine seedlings to combined levels of light and phosphorus. Seedlings were grown under three levels of phosphorous availability . two relative addition rates RAR 2 and 4 g P 100 g-1 P d-1 and a free-access to P crossed with two light levels photosynthetic photon flux densities of 150 and 450 pmol m-2 s-1 respectively . Relative growth rate RGR and relative uptake rate of phosphorus RUR were computed as well as the amount of light absorbed per seedling. We found that phosphorus and light acted as limiting factors with a complex interaction. Under low light and at the lowest P level P and light were co-limiting . growth was enhanced only when P and light were increased together. Light was the limiting factor for growth under low light conditions at all other levels of P availability. P was the limiting factor at a RAR of 2 under high light. Enhancing P from 4 to free access did not significantly improve growth under high light. RUR was controlled systematically by P availability at 2 and 4 RAR. RGR values were close to RUR values except under free access to P. Therefore growth-independent accumulation of P was observed under high P conditions. The differences in biomass production among P treatments were explained primarily by the reduced amount of radiation intercepted by the .

• Báo cáo khoa học
• Báo cáo lâm nghiệp hay
• cách trình bày báo cáo
• báo cáo lâm nghiệp
• công trình nghiên cứu lâm nghiệp
• tài liệu về lâm nghiệp