豫东黄河故道湿地景观格局及其多样性变化

应用ERDAS遥感影像解译软件,在ArcGIS软件支持下建立了豫东黄河故道湿地景观要素数据库,采用景观多样性指数、斑块特征指数和分离度等指标,分析了豫东黄河故道湿地的景观格局多样性变化规律,以及影响其格局变化的驱动力。结果表明:从各景观多样性指数的变化看,丰富度、景观最大多样性指数和景观优势度均为低洼湿地带最大,说明该地带景观类型多样化;从斑块变化特征看,由低洼带到背脊带,斑块边界趋向复杂化,性状呈现不规则变化,且斑块面积有效性逐渐减弱,不利于物种保护和湿地生态价值、生态功能的提升。豫东黄河故道湿地演化的过程中,受到自然和人为两方面演化驱动力的共同作用,其中自然因素有黄河断流、促淤造陆和湿地自身演替变化等,人为驱动力主要有农田开垦、滩涂开发及人工建筑等。

Landscape Pattern and Diversity Changes of Old Yellow River Wetland in the East of Henan Province

The data of landscape were established by ERDAS software of ArcGIS in the wetland of old Yellow River in the east of Henan Province.Landscape diversity indices,characteristic indices of patches and isolation indices were used to analyze the variation law of landscape patterns diversity and the driving force of pattern changes in old Yellow River wetland.The results show that landscape indices such as landscape diversity indices,richness,the maximum landscape index and landscape dominance are the highest in the low-lying wetland zone,illustrating the diversification of the landscape pattern.From low-lying wetland zone to dorsal wetland zone,not only the patch boundary goes to be complicate and the shape appears irregular change,but also the patch areas are gradually decreased,which would go against species protection and promoting the ecological value and function of wetland.The results indicate that during the development of old Yellow River wetland,both natural factors and anthropogenic factors have played important role on altering the pattern.The former includes decrese of discharge and sediment,self succession,while the latter consists of farmland reclamation,exploitation of tidal flat and artificial building.