The horizontal spatial distribution pattern of patch types,vector converting method,optimal grain size,vector-raster data comparison and landscape pattern of the Betahai watershed were analyzed by using common landscape indices.Tools such as ERDAS,ArcMap,Fragstats 4.0 and Excel were used to process the data.The results showed that,(1) The Bitahai lake directly connected with forest land,forming a horizontal spatial distribution pattern of lake water area →forest land → grass (northern lake) and water area →forest land (southern lake) ； the Bitahai lake was surrounded by gentle valleys,forming a horizontal spatial distribution pattern of lake water area→ marsh →marshy meadow→ meadow →forest land (western and southern lake) or the pattern of lake water area → marsh →marshy meadow →forest land (northern and southwestern lake) ； (2) Maximum combination area method was the most suitable method of grid.(3) 15 m was the optimal spatial grain size for landscape pattern analysis.(4) Forest land was the landscape subject of watershed,the aggregation degree of whole watershed landscape was high with less human disturbance,low landscape fragmentation and simple landscape shape,the ecological environment maintained a good nature state.(5) Watershed area and patch numbers had a slight increase when rasterizing with the grain size of 15 m.%利用ERDAS处理Landsat-ETM影像,ArcMap 10处理矢量数据和栅格数据,Fragstats 4.0计算景观指数值,Excel统计景观指数值,并选择一些常用景观指数,分析了碧塔海流域斑块类型水平空间分布格局、矢量转换方法、最佳空间粒度、矢栅数据比较和景观格局.结果表明,(1)碧塔海湖泊周边地势陡峭地段,湖泊水域直接跟有林地相连,形成了湖泊水域→有林地→草丛(湖泊北部)和湖泊水域→有林地(湖泊南部)的水平空间分布格局;湖泊周边的少数山间平缓谷地,则形成了湖泊水域→沼泽→沼泽化草甸→草甸→有林地(湖泊西部和南部)或湖泊水域→沼泽→沼泽化草甸→有林地(湖泊北部和西南部)的水平空间分布格局.(2)最大组合面积法是最适宜的栅格化方法.(3) 15 m是景观格局分析的最佳空间粒度.(4)有林地是流域的景观主体,而且整个流域景观聚集程度很高,人为干扰少,景观破碎化程度极低,景观形状比较简单,流域生态环境保持了很好的自然状态.(5)采用最佳空间粒度15 m进行栅格化时,流域面积和斑块数都有少量增加.
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