具有自我调节净化湿地、水量平衡、调节气候等功能的湿地植物群落的重要建群种芦苇(Pragmites australis),是重要的自然资源之一。以博斯腾湖周围区域1 050 m等高线内的芦苇湿地为研究对象,以近26 a (19902015年)的Landsat解译数据与气象、水文数据相结合,应用线性回归建模、广义线性建模等方法,分析博斯腾湖芦苇湿地的时空变化及其成因。结果表明: ① 近26 a博斯腾湖大湖芦苇面积变化以2000年为界分为2个阶段, 19902000年芦苇面积总体呈下降趋势; 20002015年总体呈上升趋势。形成这种变化的主要驱动因子为水位。② 博斯腾湖小湖芦苇面积的动态变化不太明显,19902000年芦苇面积波动上升,但幅度较小; 20002015年波动上升,变化幅度较大。其主要驱动因子是生态需水量和人为育苇等。③ 水位与芦苇面积拟合的非线性关系表明,大湖芦苇生长最佳水位为1 046. 66 m。本研究可为博斯腾湖湿地的保护和利用及其生态安全提供科学依据。
英文摘要:
As one of the important natural resources and constructive species of wetland phytobiocoenose,Phragmites australis has the self-regulation functions including the wetland purification,hydrologic budget and local climate regulation. In this study,the spatiotemporal variation of P. australis wetland within the 1 050 m contour line and its formation causes were studied using the linear regression model and generalized linear model based on the Landsat interpretation data and meteorological and hydrological data in recent 26 years from 1990 to 2015. Main driving factors of spatiotemporal variation of the P. australis wetland were analyzed. Results are as follows: ① The variation of P. australis area around the Bosten Lake could be divided into two stages by the year of 2000: the P. australis area was reduced from 1990 to 2000 but enlarged from 2000 to 2015. The main driving factor for this variation was the fall of water level. The area of P. australis was negatively correlated with water level; ② Unlike the main lake area,the variation trend of P. australis area in the small lake area was unremarkable. From 1990 to 2000,the area of P. australis wetland was reduced in a fluctuation way. From 2000 to 2015,its enlargement was remarkable. The main driving factors for this variation were the ecological water demand and artificial cultivation, and there was a positive correlation between them; ③ Results of non-linear relationship between the area of P. australis wetland and the water level revealed that the most suitable water level for P. australis growth in the main lake area was 1 046. 66 m.