新疆北疆景观格局空间分异特性研究

Study on spatial differentiation characteristics of landscape pattern in North Xinjiang

本研究利用2001和2012年MODIS土地覆盖类型产品MOD12Q1数据作为信息源,提取新疆北疆常绿针叶林、稀疏植被、农用地、雪和水等各土地利用类型信息。本研究在GIS技术支持下,运用景观生态学原理,选取反映景观空间结构和异质性的景观指数,分析该地区在11年间的景观格局及其动态变化特征。研究结果表明:随着北疆年平均气温的逐年升高,年平均降水的缓慢增加,及年平均大气相对湿度的降低,2012年相比于2001年雪和水的面积减少了5.736×105hm2。草地(主要为一年生短命植物)面积增加了1.43412×107hm2,稀疏植被(以白梭梭为建群种的荒漠植被)面积减少了3.8722×106hm2。景观优势度指数则在该期间增加了0.39,而多样性、破碎度和分维数指数则分别减小了0.39、0.06和0.03。上述变化使得北疆景观格局异质性降低,景观结构趋向单一。在气候和人文两大因子的驱动下,北疆景观格局正发生着明显改变。该变化是否会影响未来"山脉-绿洲-荒漠"这一耦合系统的稳定及可持续发展值得密切关注。

In the paper, the production MOD12Q1 data of MODIS land in 2001 and 2012 were used as the information source to extract the land- use information of evergreen coniferous forest, sparse vegetation, farmland, snow and water and so on in northern Xinjiang. We selected landscape indexes which could reflect landscape spatial structures and heterogeneities by using the principle of landscape ecology under the support of Geographic Information System（GIS） technology to analyze the landscape pattern and the dynamic changing characteristics of 11 years. The result showed that with the rise of annual average temperature and precipitation of northern Xinjiang, and the loss of annual average relative humidity of atmosphere, the snow and water area decreased by 5.736 × 105hm2, the grassland（most annual ephemeral plants） area increased by 1.43412×107hm2and the sparse vegetation（desert vegetation whose constructive species is haloxylon.persicum） area decreased by 3.8722×106hm2from 2001 to2012; the landscape dominance index increased tin the period by 0.39, while the diversity, fragmentation and dimension index decreased by 0.39, 0.06 and 0.03, respectively. These changes make landscape heterogeneity of northern Xinjiang reduce, and landscape structure tends to be single. In two driving factors of climate and humanities, landscape pattern of northern Xinjiang is undergoing significant change. Whether this change will affect future ＂Mountain- Oasis- Desert＂ stable and sustainable development of the coupling system is worth of close attention.