tailieunhanh - Báo cáo khoa học: "Nutrient cycling in deciduous forest ecosystems of the Sierra de Gata mountains: aboveground litter production and potential nutrient return"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Nutrient cycling in deciduous forest ecosystems of the Sierra de Gata mountains: aboveground litter production and potential nutrient return. | Ann. Sci. For. 55 1998 749-769 Inra Elsevier Paris 749 Original article Nutrient cycling in deciduous forest ecosystems of the Sierra de Gata mountains aboveground litter production and potential nutrient return Juan F. Gallardoa Alejandro Martinb Ignacio Santa Reginaa aCSIC Apdo 257 Salamanca 37071 Spain b Area de Edafologia Facultad de Farmacia Salamanca 37080 Spain Received 8 December 1997 accepted 12 February 1998 Abstract - The potential nutrient return in a chestnut coppice Castanea sativa Miller over a period of 3 years 1991-1994 has been established and compared with the returns found in four deciduous oak Quereus pyrenaica Wild. forests 1990-1993 located in the Sierra de Gata mountains central Spanish system . A convergence of abscission phenology patterns was observed among the different ecosystems studied together with a delay in leaf fall at the warmest plot. This similarity is logical since the plots harbour the same deciduous species which are however subjected to climatological variations. The chestnut coppice was found to be more productive than the oak forests the amounts of leaves branches flowers and total litterfall being significantly greater. Statistical analysis showed a highly significant correlation between the chestnut coppice and the oak forest aboveground production ranging between and for the leaves and between and for the total litter. In general the leaf organs of the chestnut trees showed a higher concentration of bioelements than the oaks with N and Ca predominant in the buds Ca and Zn in the branches K in the fruits and above all Fe and Cu in the other plant remains. In all the forests studied the potential nutrient supply fluctuated over the years and depended strongly on phenological factors above all it was found to be governed by the leaves which contributed most to the return of mineral nutrients to the soil. The most marked potential nutrient return through the oak aerial organs occurred on the plot with .