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干旱区干涸湖底在强烈的风蚀作用下成为盐碱尘暴的重要来源之一。为研究干涸湖底不同景观类型的抗风蚀效应,选择新疆准噶尔盆地西部艾比湖干涸湖底6种不同景观类型下的富盐沉积物为研究对象,基于沉积物样品的体积粒径分布数据,运用单重、多重分形理论和典范对应分析(CCA)排序方法,重点探讨艾比湖干涸湖底不同景观类型下富盐沉积物粒径分布分维值的分异特征。结果显示:胡杨林带(L1)、乔本结合带(L2)、草本结合带(L3)、芦苇荒漠带(L4)、梭梭荒漠带(L5)、无植被覆盖(L6)6种景观类型0～30cm和30～60cm的富盐沉积物分维值分别存在显著性差异。各景观0～30cm分维值介于1.94～2.40,30～60cm分维值介于1.92～2.53,总体均处于低位水平。0～30cm平均分维值依次为L5>L1>L6>L4>L2>L3,30～60cm平均分维值为L5=L1>L4>L6>L2>L3。富盐沉积物粒径分布分维值与粒径小于73.63μm的体积含量呈显著正相关。研究表明多重分形维数和CCA排序方法可以有效的揭示干涸湖底自然植被条件下不同深度富盐沉积物粒径分布的均匀性特征。指出干涸湖底风蚀控制研究方向应集中在根据湖区的富盐沉积物-植物特征,对富盐沉积物性状进行改良,提高原生物种幼苗存活率,通过生态修复防治盐尘暴。
The dry lake bottom in the arid area has become one of the most important sources of salinity and alkali dust storm under the action of strong wind erosion. In order to study the anti-wind erosion effect of different landscape types in dry lake bottom, salt-rich sediments under six different landscape types of dry lake bottom in the western part of the Junggar Basin in Xinjiang were selected as research objects. Based on the volume data of sediment samples, Heavy, multifractal theory and Canonical Correspondence Analysis (CCA) method, this paper focuses on the differentiation characteristics of the fractal dimension values of the salt-rich sediment particle size distribution under different landscape types in Lake Ebi. The results showed that there were 6 landscape types 0 in Populus euphratica forest zone (L1), Qiaomomb zone (L2), herb zone (L3), reed desert zone (L4), Haloxylon desert zone (L5) and no vegetation cover The fractal dimension values of ~ 30cm and 30 ~ 60cm of salt-rich sediments were significantly different. The fractal dimension of 0 ~ 30cm of each landscape ranged from 1.94 to 2.40, the fractal dimension of 30 ~ 60cm ranged from 1.92 to 2.53, all at low level. The average fractal dimension values of 0-30 cm were L5> L1> L6> L4> L2> L3, and the average fractal dimension of 30-60 cm was L5 = L1> L4> L6> L2> L3. The fractal dimension value of the particle size distribution of salt-rich sediment is positively correlated with the volume fraction of particle size less than 73.63 μm. The results show that the multifractal dimension and the CCA ranking method can effectively reveal the uniformity of the particle size distribution of salt-rich sediment at different depths under the dry lake natural vegetation. It is pointed out that the research direction of dry wind erosion control at the lake bottom should focus on improving the characteristics of salt - rich sediment according to the characteristics of salt - rich sediment - plant in the lake area, improving the survival rate of the seedlings of native species and preventing and curing salt - dust storm by ecological restoration.