| A part of aerial photography of the spring in 2008 and land use map of Zhengzhou City were used in the paper, and stream segment off Jialu River in Zhenghzou was taked for example (study areas extent 600 meter on on both sides along the centerline of Jialu River, and it was 57Km from Jialu town of Xingyang City to Zhongmou.) combining GPS field survey data on June, 2008, aerial photographies was conducted Landscape classification, and quadrats were established in study area to investigate plant diversity. The landscape of study area were divided in four types incleded arable land, construction land, forest and water. According to the factors of topography, roads and rivers, study area were divided in four kinds of gradient included far suburban area on upper stream (the first gradient), near suburban area on upper stream (the second gradient), urban riverine zone (the third gradient)and riverine zone on lower stream(the fourth gradient). 11 parameters inclued the Number of patches, Patch density, marginal density, average shape index, landscape diversity index, landscape dominance index, landscape evenness index, landscape richness index, landscape neighbor index, landscape separable index and landscape fragmentation index were selected to study landscape pattern. 4 parameters included richness index, diversity index, pielou evenness index and dominance index were selected to study plant diversity. The characteristics of landscape patterns and plant diversity of Jialu River were analyzed through the softwares included AUTOCAD,SPASS,EXCEL and FRAGSTATS and so on, and the measures of landscape pattern optimization and plant variety protection were offered according to landscape ecology theory and restoration ecology theory, which can provide scientific proof to ecological restoration and construction of stream segment off Jialu River in Zhengzhou. The results show that:The analysis of component structure of the landscape showed that: The gradient type of space occupied proportion of arable land were 47.74%, 42.74%, 27.7%, 46.4%; The proportion of space occupied forest types were 31.91%, 26.04%, 12.91%, 12.98%, respectively; The proportion of space occupied land for construction were 13.98%, 22.38%, 53.9%, 18.1%, respectively; The proportion of space occupied water bodies were 6.37%, 8.84%, 5.57%, 22.6%, respectively. Compared to its analysis, land for construction was the main area for the higher degree of urbanization gradient. Area of arable land and rivers were relatively small. Arable land and woodland were the main area for lower degree of urbanization gradient. Because the lower reaches of the river area is close to the Yellow River, the existence of large-scale fish ponds, the proportion of water were relatively high. The demand generated by the urbanization process has a greater impact in land use patterns of Jialu River in Zhengzhou.The analysis result of the change of gradient of landscape diversity demonstrates that landscape diversity index, landscape regularity index and degree of dominance index can reflect the landscape diversity characters in the survey region.The arrange order of the above two is the fourth grads>the second grads>the first grads >the third grads. The arrange order of degree of dominance index is opposite the above two. It reflect that the construction land plaque type has the leading position, but the landscape plaque type in the lower reaches is relatively average. It has no dominant landscape type. The result also explain that the landscape diversity of the fourth grads is relatively big, having higher ecological stability. But the landscape diversity of the third grads is relatively small and the ecological system is not stable.The analysis result of the landscape fragmentation degree demonstrates that the fragmentation index of woodland is high and the fragmentation index of water body is low in the first grads. This indicates fragmentation degree of woodland plaque is relatively higher. which is because of the topographic condition. The fragmentation degree of water body is relatively lower and the continuity is the best. The fragmentation index of woodland is higher and the arable land is smaller in the second grads. This indicates the woodland influenced by humanity is the most serious. The fragmentation degree of arable land is small. The fragmentation index of the water body is higher and the construction land is smaller in the third grads. This indicates the water type influenced by humanity is the most serious. The connection degree of stroma plaque in the construction land is the highest. The fragmentation degree of water body is relatively higher and the construction land is smaller in the fourth grad. This indicates that the grads distribute many pounds which influenced by humanity are the most serious. Construction plaque is a little and relatively centralize.Landscape patch shape gradient analysis showed that: Edge Density index reflects the patch shape characteristics of the gradient: the first gradient> fourth gradient> second gradient> third gradient, it shows the upper reaches of the outer zone are complex shapes of the mountain patch; urban river zones were the nearest to the city, influenced greatly by urbanization, the shape of patch is regular. The average shape index shows patch shape characteristics different landscape types in gradients, arable land and construction land decrease along the gradient directions; water body increases along the gradient directions; forest land decreases along aggrandized urbanization. Arable land,construction land and forest gradient shapes increase along terrain changes from fluctuation to flat and human disturbance factors, but water body decreases.Plant composition analysis revealed that: there are more the Salicaceae, Rosaceae, Leguminosae, Oleaceae species in woody plants, less other families. There are more Asteraceae and Poaceae in herb plants, species are mainly based on native trees, and the introduction of the fine plant species is less. Plant diversity, evenness and richness are higher in urban river zones but lower in the lower reaches of the river area; dominance is higher in the upper reaches of the outer zone but lower in upper reaches of the peri-urban areas. As the distance from the urban centers increased, plant diversity, evenness and richness increased, this indicates that the process of urbanization have a greater impact on the species composition structure of the region.Optimization measures:Increasing the forest,water body areas of the urban rivers areas, Improving the landscape diversity of urban river areas, Thus increasing the ecological stability. Protecting the arable land and forest's patches of Gradient 3. making Building space and green space for mutual penetration. Widen the river, make use of eco-revetment, restorate the natural patterns of river. To increasing the water body's proportion of the Jialu River; To strengthen the connectivity, and to interchange and continuity planning green in the nodes; protecting the ever or current wetlands, woodlands, scenic areas, historical and cultural relics and other ecologically sensitive areas in the both sides of Jialu River, meeting the needs of the ecological environment of Zhengzhou. By promoting the application of agroforestry systems, Improving resource utilization, conserving water sources, soil and water, and improving the productivity of green; Excavating the potential of native plant species depthly, increasing the application of good native plants, At the same time, introducting plant species with similar habitat, taking human disturbance on plant diversity into a benign orbit appropriatly.
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