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Study on the Characteristic of Litter of Artificial Spruce Forest in the Central of Tianshan Mountain

Author: ZhangHongLiang
Tutor: ZhuJianZuo；ZhangXinPing；ZhangZuoTao
School: Xinjiang Agricultural University
Course: Ecology
Keywords: Tianshan Central artificial spruce forest litter nutrient decomposition
CLC: S714
Type: Master's thesis
Year: 2010
Downloads: 38
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Abstract

The Tianshan spruce Pinaceae（Picea schrenkiana Fisch.et Mey. P.schrenkiana）is an evergreen tree of gymnosperm,it is a variant of Schrenk spruce and a endemic species in China.There are large areas of artificial spruce forest in Xinjiang.The forest not only provides a large number of commodities with the material,but also maintain the ecological balance of forest systems in Xinjiang.However,slower growthing, lower productivity,soil fertility declining limited healthy managing and continuable development of the artificial spruce forest in central of the Tianshan.The current study on the artificial spruce forests is relatively fewer in the central of the Tianshan.There are almost not articles about litter quantity,composition,nutrients,decomposition and other features of the artificial spruce forest. In order to enhance productivity of the artificial spruce forest,promote ecosystem benign cycle,the characteristics above mentioned were studied in ShaVan forest farm.The results show that:1. Spruce forest in central of the Tianshan, litter total amount was 2485.14Kg·hm^-2·a^-1.Among the component, the leaf amount was 1828.37 Kg·hm^-2·a^-1,accounting for 73.6% of the total litter;the drop-sticks amount was 599.32Kg·hm^-2·a^-1,accounting for 24.1% of the total litter; the skin and fruit droping amount was respectively 15.62Kg·hm^-2·a^-1 and 14.29Kg·hm^-2·a^-1,respectively accounted for 0.63% and 0.58% of the total litter; other litter amount was 27.55Kg·hm^-2·a^-1,accounting for 1.1% of the total litter.2. Spruce forest in central of the Tianshan, the maximum total litter amount appeared in July.The amount was 701.07 Kg·hm^-2. The mimum total litter amount appeared in December.The amount was 35.56 Kg·hm^-2·a^-1. The litter amount was 90% of the year total litter among May and October. The litter amount was 10% among April and November. The leaf amount was respectively 568.63 Kg·hm^-2 in June and 549.67 Kg·hm^-2 in July.The amount accounted respectively for 89.14% and 78.40% in the month.3. The litter of artificial spruce forest in central of the Tianshan, Ca content was the most in total nutrient elements. Ti’s amount was 13.95 g·Kg^-1; N content was 8.43 g·Kg^-1; K and Mg contents were respectively 3.86 and 2.92 g·Kg^-1.The nutrient element contents in the order: Ca>N>K>Mg>P. Ca, N, K and Mg concentration in leaves was higher. Ca content is the most and P was the lowest in Skin among the all organic composition. N content of fruit was higher than branches and bark. The nutrient contents of other organic composition were relatively low.4.For the artificial spruce forest In central of the Tianshan,nutrient total return 79.241 Kg·hm^-2 to soil each year, in which,Ca return 34.375 Kg·hm^-2;N return 25.966 Kg·hm^-2;K return 8.465 Kg·hm^-2;Mg return 6.841 Kg·hm^-2;P return 3.594 Kg·hm^-2.The order was Ca>N>K>Mg>P.5. For the artificial spruce forest In central of the Tianshan, modol of leaf decomposition was Y = 99.782e^{（-0.0004x）};modol of branch decomposition was Y = 96.544e^{（-0.0009x）}; modol of bark decomposition was Y = 99.962e^{（-0.0003x）};modol of fruit decomposition was Y = 100.79e^{（-0.0006x）}.The 50% decomposition time of leaf, branch,bark and fruit was relatively 1727 days,731 days,2309 days,1168 days.

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