【作者】 张丙昌； 张元明； 张静； 吴楠；

【Author】 ZHANG Bing-chang~1,ZHANG Yuan-ming~1,ZHANG Jing~(1,2),Wu Nan~1 (1 Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China,2 Key Laboratory of Biogeography and Bioresource in Arid Land,Urumqi 830011,China,3 Graduate University of Chinese Academy of Sciences,Beijing 100039,China)

【机构】 中国科学院新疆生态与地理研究所； 干旱区生物地理与生物资源重点实验室新疆； 中国科学院研究生院；

【摘要】 通过春、夏、秋3季对古尔班通古特沙漠典型沙垄不同地貌部位进行采样、培养、和生物量测定,从藻类物种多样性、种类组成和生物量几个方面分析了该区典型沙垄中藻类的时空分布特征。结果表明:1)地貌部位和不同土层对物种多样性指数影响极显著(P<0.01),坡部藻类物种多样性指数最高,垄间低地居中,垄顶最低;在垂直层次中,藻类物种多样性指数由表及里逐渐降低。2)在不同地貌部位和季节中,藻类的种类组成亦表现出一定的差异。垄间低地和背风坡球形藻类和丝状藻类丰富,迎风坡以丝状藻类占优势,垄顶藻类的种类和数量都有明显的下降;具鞘微鞘藻(Microcoleus vaginatus)是不同地貌部位是最明显的优势物种。藻类优势物种和常见物种在不同季节中不同。3)地貌部位、垂直层次和季节对藻类生物量的影响均极显著(P<0.01)。藻类生物量的变化趋势是在垄间低地最高,迎风坡与背风坡居中,垄顶最低;在垂直层次上一般表现为由表及里急剧下降;除垄项外,藻类生物量一般表现为春季最高,夏季次之,秋季最低。藻类在沙漠典型沙垄的分布具有空间异质性,将影响到生物结皮的发育,使其处于不同的发育阶段,而它们在生物结皮中的地位和作用亦不同。更多还原

【Abstract】 In spring,summer and autumn of 2007,soil samples colleted in the different sand locations were cultured and identified.Algae biomass of soil samples was measured.The temporal-spatial distribution of algae was determined by species diversity,species composition and biomass.The results indicated that:1) Species diversity was significantly affected by locations of sand dunes and soil layers with different depth(p<0.01).Species diversity of algae in windward and leeward of sand dunes were the most abundant,followed by inter-dune areas,and top of sand dunes was the lowest.In vertical layers of all sand locations,species diversity of algal declined with the deepening of soil layer.2) Some differences were observed for algal composition in different sand locations and seasons.In inter-dune areas and leeward,coccoid and filamentous algae were abundant;in windward,only filamentous algae were dominant.However, taxa and number of algae were decreased obviously in the top of sand dunes.In some sand locations,some algae were found in different seasons,otherwise,the number of the algae was different,which led to changes of dominant species and common species.Microcoleus vaginatus was the main dominant species in different sand locations.The other dominant species changed in different sand locations and seasons.3) Sand locations,layers with different depth and seasons had highly significant effects on algal biomass(P<0.01).The total changing trend is that algal biomass in inter-dune areas was the highest,followed by windward and leeward,biomass in the top was the lowest.Algal biomass reduced sharply with the depth from the surface to deeper layer. For algal biomass,no seasonal changes were observed in the top of sand dunes.However,there were obvious seasonal changes for algal biomass in other sand locations,algal biomass in spring was the highest,followed by summer,and autumn was the lowest.There was temporal-spatial heterogeneity for algal distribution in sand dunes in Gurbantunggut Desert.Heterogeneity of algal distribution may have some effects on the development of biological soil crusts(BSCs),which may make BSCs be different developmental stages.Algal distribution in different BSCs made the role and status of algae change.更多还原