Study On The Underground Biomass Of Community Dominant Species In Middle Reach Of Tarim River

By the study in middle reach of the Tarim River Nature Reserve about biomass of dominant species under ground, surface and the correlation and distribution of both parts of biomass in two years (2004-2006 ). The results show that in the middle reach of the Tarim River Phragmites australis (Cav.) Trin. ex Steud. biomass is up to 728.21g/m2, in which biomass aboveground is 165.83g/㎡, or about 23% of the total, biomass underground accounts for 77%. Biomass in Tamarix dunes is 17.3 kg/m2, biomass aboveground is 3.4 kg/m2, or about 19.7% of the total, below-ground biomass is about 80.3%. The Populus euphratica Olive biomass of two samples beside river is 193 kg, each 96.5kg. A Populus euphratica Olive above dune is dug out with grab whose weight is 394kg.Equation of quadratic nonlinearity of Phragmites australis (Cav.) Trin. ex Steud.can explains ratio of the above-below-ground. Phragmites australis (Cav.) Trin. ex Steud. underground biomass is decreasing while soil depth increases generally: biomass reaches the highest between 30-40cm in soil, accounting for 22.8% of biomass underground, then decreases with the increase in soil depth, 14.8% in 0-10cm, 19.3% in 10cm-20cm, 15.8% in 20cm-30cm 18.5% in 40cm-50cm and, 9% in 30cm-40cm and. Tamarix ramosissima Ldb. underground biomass decreases as soil depth increases, The maximum appears in 40cm under the soil which covers 38.7% of underground biomass and 27.4% in 40cm-80cm, 14.1% 12.1% and 8.6% in 80cm-120cm; 120-160cm and 160cm-200cm。The study aims at a in-depth understanding on the potential underground ecological process of dominant species in the middle reach of the Tarim River Nature Reserve through quantity and distribution of underground biomass and correlation of the above-below-ground biomass, accurately assessing biomass productivity of the whole ecosystem in this region and laying a foundation for scientific and effective environmental protection and management.