| Mineral nutrient elements nitrogen, phosphorus, potassium and calcium were an important component of kiwifruit and the foundation nourishment in food chain for life and plant growth. They are correlative with protein, grease, nucleic acid and vitamin and so on. At the same time, they are important for keeping balance of nutrition resources in ecosystem, increasing yield, improving quality of farm prodution, reducing pollution and improving human nutrition. Ten–year–old Qin Mei (Actinidia Deliciosa cv. Qinmei) kiwifruit trees were used as experiment material, roots distribution, and biomass, elements content and accumulation in different organs in different periods were studied in this paper. The results showed as the follows:1. Study on the dynamics of biomass and roots distribution in kiwifruit treeBiomass increment of roots, stems, leaves and fruits were 1.33 kg,4.24 kg,1.64 kg and 4.93 kg,the whole plant increased 12.14 kg in one year. Biomass of fruits vegetated slowly after the early days of July. Biomass of stems developed more quickly from March 28 to November 6, then changed less. Biomass of leaves increased rapidly from March 28 to May 18 and September 8 to November 6, and slowly between May 18 and September 8. Roots developed quickly from March 28 to May 18 and July 9 to September 8, vegetated slowly from May 18 to July 9 and September 8 to November 6, and stop after November 6. 78.1% of roots distributed in the 0-40cm soil, the deep of soil the less of roots.﹥1cm root accounted for 60.23% of the whole roots, 91.33% of them distributed in 0-40cm soil, and without under 60cm. 0.2-1 cm root accounted for 32.34% of the total number, 51.79% of them distributed in 20~40cm soil, 20.96% of them distributed in 40~60cm soil.﹤0.2 cm root accounted for 7.44% of the total amount, 35.08% of them in 20~40cm soil, 19.62%, 22.85% and 14.52% of them in 0~20cm, 40~60cm and 60~80cm respectively, just 7.93% in 80~100cm soil.2. Study on Absorption, Using and Storage of Nitrogen in Kiwifruit TreeNitrogen content order in organs were roots, leaves and fruits > stems; cortex > xylem. In winter, tree storage of foliar absorbed nitrogen in the cortex of roots and stems, and most of them in the cortex of stems. Total 216.78 kg/ha nitrogen was absorbed in a year(harvest was 40.16 t/ha), 33.75 kg/ha nitrogen was absorbed from harvest season to fruit period and 183.03 kg/ha nitrogen was absorbed in fruit growing period, accounted for 15.57% and 84.43% of total uptake respectively, and 53.13% and 31.30% of total uptake was absorbed from May 18 to July 9 and July 9 to September 8 respectively. Total nitrogen in orchard was 412.91 kg/ha in one year, 64.29 kg/ha of nitrogen was as base fertilizer in forced dormancy period, 219.38 kg/ha was used to topdressing just before fruit period, and the rest of 129.24 kg/ha was also used to topdressing in the last day of the rapid growing phase of the fruit.3. Phosphorus Dynamics and Fertilization Management of Kiwifruit TreePhosphorus content order in organs were roots, leaves and fruits > stems; cortex > xylem. From March 28 to May 18 78.89% of phosphorus needed by leaves came from soil, 4.44% came from root transportation, and 16.67% came from stem transportation. The phosphorus absorption capacity of plant is much more than other periods from May 18 to July 9, it occupied 55.40% of total uptake, so this period was maximum efficiency period of phosphorus absorption. Total 36.95 kg/ha phosphorus was absorbed in a year(harvest was 40.16 t/ha), 10.92 kg/ha phosphorus was absorbed from harvest season to May 18 and 26.03 kg/ha phosphorus was absorbed in fruit growing period, accounted for 29.55% and 70.45% of total uptake respectively. Total phosphorus in orchard was 92.38 kg/ha in one year.4. Potassium Dynamics and Fertilization Management of Kiwifruit TreePotassium concentration order in organs were fruits > leaves≥cortex of one year branch≥cortex of two year branch≥cortex of limb≥cortex of trunk and cortex of roots > xylem of roots and xylem of one year branch > xylem of two year branch, limb and trunk. From March 28 to May 53.15% of potassium needed by leaves came from soil, 22.84% came from root transportation, and 24.01% came from stem transportation. The potassium absorption capacity of plant is much more than other periods from May 18 to July 9, was 88.57 kg/hm2. In this period, leaves transferred 31.03% of its potassium to other organs. Total 167.88 kg/ha potassium was absorbed in a year(harvest was 40 t/ha), 43.18 kg/ha was absorbed from harvest season to May 18 and 124.70 kg/ha was absorbed in fruit growing period, accounted for 25.72% and 74.28% of total uptake respectively.5. Study on the dynamics of calcium nutrient in kiwifruit treeCalcium content order in organs were leaves > roots > stems > fruits, cortex > xylem. Calcium content in xylem changed less, but fluctuated in cortex. Calcium content in cortex of stems was between 13.21 g/kg and 27.54 g/kg, in xylem of stems between 1.12 g/kg and 2.14 g/kg, in cortex of roots between 19.03 g/kg and 25.00 g/kg, and in xylem of roots between 6.35 g/kg and 7.55 g/kg. The study showed that trees could produce 50 kg fruits by absorbing calcium 227.41 g. The calcium accumulation has risen perpendicularly from March 28 to November 6,from 64.21 kg to 153.19 g, then dropped to 117.58 g in January 11 (tree dormancy).6. Study on the tree calcium accumulation and distribution in kiwifruit tree in fruit maturity periodBiomass of plant was14.32 kg, order in organs were stems (5.59 kg, 39.04%) > fruits(4.93 kg, 34.43%) > roots(2.9 kg, 20.26%) > leaves(0.9 kg, 6.28%). Calcium content order in organs were leaves > roots > stems > fruits, thin roots>thick roots, old stems > young stems, cortex > xylem. Calcium accumulation order in organs were stems roots(49.29 g, 38.64%) > stems(43.12 g, 33.80%) > leaves(23.30 g, 18.26%) > fruits(11.65 g, 9.13%).The biomass of cortex and xylem were 4.79 kg(33.45%) and 2.65 kg (18.51%),and Calcium accumulation were 57.49 g (45.14%) and 11.83 g (9.29%).
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