TAILIEUCHUNG - Báo cáo khoa học: " Water extraction by tree fine roots in the forest floor of a temperate Fagus-Quercus forest"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: " Water extraction by tree fine roots in the forest floor of a temperate Fagus-Quercus forest. | 141 Ann. Sci. For. 1998 55 141-157 Inra Elsevier Paris Original article Water extraction by tree fine roots in the forest floor of a temperate Fagus-Quercus forest Christoph Leuschner Plant Ecology FB 19 University of Kassel Heinrich-Plett-Str. 40 34132 Kassel Germany Received 15 January 1997 accepted 19 June 1997 Abstract - Water retention and water turnover were investigated in the forest floor of a temperate mixed Fagus-Quercus forest on poor soil in NW Germany. By field and laboratory measurements the aim was to quantify the water extraction by those tree fine roots that concentrate in the superficial organic layers. The organic profiles stored up to 45 mm of water under Quercus trees but significantly smaller amounts under Fagus and even less under Pinus trees in a nearby stand . The water retention capacity . the difference between saturating water content after wetting and water content prior to wetting and the resulting percolation rate out of the forest floor were measured by infiltration experiments in relation to their dependence on the initial water content of the humus material. The water retention characteristics of the humus material differed from the sandy mineral soil material by i a much higher maximum water content porosity ii a higher storage capacity for water in the plant-available water potential range and iii a marked temporal variability of the water retention capacity. A one-dimensional water flux model for the forest floor of this stand has been developed. According to the model results the forest floor contributed 27 in summer 1991 or 14 in summer 1992 to the stand soil water reserves and 37 summer 1991 or 28 summer 1992 to the water consumption of this stand. Water was turned over in the forest floor twice as fast as in the underlying mineral soil however fine roots in the mineral soil apparently extract more water per standing crop of root biomass and thus are thought to operate more economically with respect to 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