The Study On The Growth Rule Of Picea Schrenkiana Var. Tianschanica And The Productivity Of Communities In TianShan

Biomass and net primary productivity (NPP) of plant community are important ecological indexes which can reflect structure and function of a ecosystem. They are very important for ecosystem because they can measure the relative importance of community in a ecosystem and also measure the carbon sink and carbon cycling in a ecosystem. Studying biomass and productivity of communities can disclose the rule about energy balance, energy flux and nutrient cycling. It also can estimate the supporting capacity of globe and to evaluate the sustainable development of land ecosystem.Picea schrenkiana var. tianschanica forest is a most extensive vegetation style of Tian Shan in Xinjiang Province, as well as a 'wet island' in vastness desert. It is also headsprings of many rivers. The precious water has maintained the environment of oasis and the development of the industry, agriculture, stock raising, and economy in center of Xinjiang. To research biomass and productivity of Picea schrenkiana var. tianschanica forest can maintain and improve the healthy and vigor of the type forest because it is an important forest style of TianShan forest ecosystem. At the same time, the result of this study can become important source of information for the ecological networks because Tianshan State Forest Ecosystem Station is a main branch of Chinese Forest Ecosystem Research Network (CFERN). In this paper, the plant communities were sampled and analyzed in Tianshan State Forest Ecosystem Station. We take a method that field investigations and indoor tests were integrated to study the biomass and productivity of plant community in Tian Shan according to the principals of ecology and forest measurement. At the same time, we analyze the growth of Picea schrenkiana var. tianschanica by the data from the research of standard trees. From this research, we obtain the following conclusions:1 There are marked relativity between DBH and height of trees, between DBH and the ratio of height to DBH. The relativities can be described by the model, H=3.0683+0.3936Z) and F=0.713 8-0.006 3D.2 The productivities of Picea schrenkiana var. tianschanica have obvious difference among the different stem classes. The thicker the stem is, the higher the productivity is.3 The distribution of Picea schrenkiana var. tianschanica organs have obvious rule in different tree height. The percentage of the stem and bark biomass decrease with the height of trees increasing;the leaf's pecentage increase with the height of trees increase;thebranch's percntage is bigger in the center trees than in the topper or the lower trees. The root biomass of trees distribute regularly in level and vertical orientation. The most biomass is distributed within the 2 m scope in the level orientation, 10 cm in the top soil in the vertical orientation.4 By sampling plot harvesting method and allometry method, we measured the biomass and net primary productivity (NPP) of plant community in Tianshan State Forest Ecosystem Station in Xin Jiang Province. The biomass of grass-Picea schrenkiana var. tianschanica community, S.tianschanica Rupr-Picea schrenkiana var. tianschanica community, J.pseiidosabina Fisch.et May-Picea schrenkiana var. tianschanica community, Berberis sphaerocarpa Kar.et Kir community, Caragana camilli-schneideri Kom community, subalpine grass were 259.94 thm~*\ 210.977 t-hm"2, 91.391 t-hm'2> 23.156 thnV2, 12.547 thm~2> 4.442 t'hm"\ 0.746 tvhm"2 , respectively;The productivity of those communities were 6.459 t-hm'V. 4.197 thm"2-a"', 3.969 t-hm"2-a"', 3.907 t-hm"2-a"' > 2.759 t-hmV, 1.193 t-hm'V. 0.418 t-hm'V .respectively.5 The biomass and productivity of community were affected by the styles of community and the altitude intensely. The biomass and productivity of communities increased quickly with the altitude hoisted higher and higher from altitude 1 813 m to 1 965 m. Then the biomass and productivity became lower and lover with the altitude got higher and higher from altitudel 965 m to 2 630 m. The slope site where the communities grow has an important effect to the biomass and productivity. There was a trend that the biomass and productivity decreased from the hill bottom to hilltop.