寡营养细菌(Oligographic bacteria)及其固沙作用的研究

 从新疆古尔班通古特沙漠生物结皮的下层(沙物质层)分离到一株寡营养细菌,G +;细胞大小在0.328~0.746×0.171~0.240 μm;菌落圆形;直径5 mm,白色光滑,隆起明显;兼性好氧;该菌可在含碳量1~15 mg\5L-1培养基、10~70 ℃、pH值 5~11的环境中生长,较适宜生长温度范围为15~37 ℃;最适pH值范围为8~9;该菌在生长过程中分泌大量的黏多糖,室内培养72 h黏度可达9 000 mPa·S。将黏度为1 500 mPa·S的菌体培养液喷洒在流沙表面后,能够形成可以粘连沙粒约6 mm厚的寡营养细菌结皮层,该结皮层不仅能够固沙而且具有一定的减缓土壤中水分蒸发的效果。

Oligotrophic Bacteria and Its Sand Stabilizing Effect

A oligotrophic bacteria was isolated from the underlayer of biological crusts in Gurbantunggut desert. The cell size is 0.328~0.746×0.171~0.240 μm. The pileus is round and in white color, and its diameter is 5 mm. The thalli is a facultative aerobe and can grow in medium of 1~15 mg·L-1 C content, 10~70 ℃ and pH 5~11. The suitable ranges are 15~37 ℃ and pH 8~9. A lot of mucopolysaccharide was secreted during the growth of oligotrophic bacteria. The viscosity can reach 9 000 mPa·S after the thalli have been cultivated for 72 hours. If a bacteria culturing solution whose viscosity is 1 500 mPa\5S was sprinkled on shifting sandsurface, a bacteria crust of 6 mm conglutinating sand could be formed. The crust can not only stabilize moving sand but also can slower the rate of soil moisture evaporation.