Rebuilding Greening Environment Of Farmer's Relocated Quarter

Urbanization and New Countryside are important procedures to realize Chinese urban-rural integration. Moderately concentrating farmer's settlement has become a principle trend of rural urbanization. And most of the land-lost farmers accept relocated quarter as their arrangement form. However, there are still some problems about greening landscape of quarter environment such as negative influences of tree on housing, no seasonal change, plant attracting worms or causing allergy, numerous unfamiliar neophytic species, few hometown landscape, and unreasonable center green space. The problems will affect farmers'safety, healthy, comfort and feasibility, and the greening satisfaction will fall down. It is also helpless to sustainable development. Therefore, we would try to conduct further research on greening idea, model and methods for relocated quarter.This study took Shanghai as one case to survey 28 relocated quarters,10 traditional villages and one private garden. There were altogether 387 farmers as respondents to finish questionnaires. Then SPSS 13.0 software was used to analyze data, and computer model technology (Auto cad 2005 and Sketch up 5.0) was applied to build models between tree and housing. Furthermore, four-digit code was built for one tree with tree height, defoliation, direction and diatance to realize data analysis. Main research contents are:general greening features of relocated quarter; plant species abundance, greening plain structure and vertical structure of relocated quarter and traditional village so as to get new ideas and models; tree configuration next to building; and construction and management of relocated quarter. We tried to put forward theories of plant species composition, greening structure, tree configuration and management for the integrated greening environment of relocated quarter.The main research results can be concluded as follows:1. Comprehensive cognition was got of plant species composition of both relocated quarter and traditional village. The plant richness (Gleason index, GI) of relocated quarter was higher than that of village with 134.93 vs 77.10 (GI:13.83 vs 8.75). The proportion of artificial plant species of relocated quarter was also higher that of village with 89.1% vs 66.9%, while indigenous species, wild species and tree species were on the contrary with 64.4% vs 76.7%,9.1% vs 31.5%,22.2% vs 33.7%, respectively. GI of relocated quarter showed decreasing trend from urban center to suburb on the scale of region; the same trend happened temporally from 1990s to 2000s. Tree species diversity index (SHDI) of relocated quarter was 2.771, in which there was spatially lowest value at the inside of outer-ring meanwhile highest at the outside of outer-ring/inside of suburb-ring. And temporally quarters in 2000s had higher SHDI than quarters in 1990s. We can conclude that relocated quarter should increase the proportions of indigenous and tree species2. Substantive results of greening structure were found at both relocated quarter and traditional village. The ratio of evergreen and deciduous tree (REDT) of relocated quarter was higher than that of village (1.14 vs 0.75), the same was the REDT of dominant species (3-5:1 vs 1:1-2). Tree height and REDT had negative correlation at 0.01 levels in village. Thus relocated quarter should promote the proportion of deciduous tree. Larger deciduous tree and small evergreen tree form a reasonable community structure.3. Model analysis was conducted in tree configuration with adjacent buildings. The formula of tree height and building distance could be found under certain conditions:hi=(d-Φ/2-1.5)/(ctg a×cos (3)+ hy+hs+0.9. It could be used to quantify how high a tree between definite buildings. General tree forms (evergreen and deciduous) were quantified with the formula to get optimal largest tree, and model analysis was conducted as well simultaneously. It is concluded that the descending orders of permitted tree height are cylindrical, conical, spherical and inverted conical between the same buildings. And of the same tree shape, its deciduous tree would be higher than its evergreen one. Among the three greening layout models between buildings (road center, greening center, alternative of road center and full greening), the last would be allocable for largest tree.4. Several theories were tried to put forward for the greening landscape of relocated quarter: "Differentiation greening model" and "Layering greening model with upper deciduous and lower evergreen trees" for the plant species composition of plain and vertical structures; "Both inner multi-center green space and outside shared green space models" for the layout of green space; "Bi-directional landscaping model" for greening space next to housing; "Formula and models of tree configuration to buildings" for quantified preferable tree species and configuration to residential buildings; "Participated two-field system (yard) greening model" (including "Participated greening model", "Two-field system model" and "Yard greening model") for the construction and management of relocated quarter. The theories are interrelated each other into an organic whole.The main innovations of this paper are to put forward theories of one idea, one formula and six models for relocated quarter. It is expected as directory for the planning, design, construction and management of future farmer's relocated quarter.