| CZT is in the eastern Hunan province, including three cities: Changsha, Zhuzhou and Xiangtan. It locates in the lower reaches of Xiangjiang River, forming a triangle, 45 kilometers from each other. The total area of CZT is 28, 106 square kilometers. It occupies 13. 3% area of Hunan province. The core area occupies 4500 square kilometers. It has a population of 12, 344, 700 in 2003, which is 18.5% of the provincial population. 44. 5% of the area is urbanized. GDP and financial revenue of this area is 33.2% and 42. 1% of that of the province respectively. In 1997, the provincial government decided to integrate the three cities so as to make the region the provincial and even the Middle Eastern high and new-technology industries development zone, urban agglomeration which will become an engine of growth of Hunan Economy. After 8 years of development the environment of the three cities has seriously restricted their development and the construction. So from the regional point of view, the study of landscape ecology of green space not only features in environmental construction of CZT urban agglomeration, but also sets an example for the study of green space of subtropical urban agglomeration.The dissertation is supported by the" the study of the integration and layout of modern forest system, the structure of ecological system of CZT". A fruitful study of the conditions of green space, typical sector, layout of landscape, ecological functions, vegetation landscape, public awareness of public green space and conception of green space is made in the article.1.The study of natural landscape resource shows: ①utilization ratio of forest land, arable land and residence land are high. From 1996 to 2001, proportion of forest land, arable land and grassland increased. The growth rate of forestland is over 8%, the growth rate of arable land and grassland are about 4%. From 1996 to 2001, the proportion of unused land decreased about 5%. The features of land resource are diversity of land type, distinct regionaldifferences and high natural productivity. ②In CZT, there is 128,049.7 hectares of forest is—26.3% of total forest area; 11, 075. 6 hectares of open woodland —2.3% of total forest area; 28,316.9 hectares of shrubbery —5.8% of total forest area; 3, 359. 0 hectares of no stumpage forest —0. 7% of total forest area; barren mountain is—0. 8% of total forest area. Forest cover rate of the region is 37. 6%. The sequencing of land for forest of the three cities is: Zhuzhou>Changsha>Xiangtan. The sequencing of proportion of forest of land for forest is: Changsha>Zhuzhou>Xiangtan. Xiangtan has the lowest proportion of shrubbery of land for forest. The sequencing of proportion of open woodland and underage forest of land for forest is: Changsha>Zhuzhou>Xiangtan. The sequencing of the area of open woodland of each city is: Zhuzhou>Changsha>Xiangtan. ③water resource problems faced by the region: serious precipitation deficit, little surface water resource, increasing total service discharge; deterioration of water environment of trunk stream of the Xiang River, drinking water resource is limited. ④ There are three types of tourist resources—cultural, natural and other; 12 scenic sites which have special features and 8 top tourist lines in the region. The 8 top tourist lines are the tour of Chu culture; the tour of Xiang River; the tour of fireworks; the tour of hometown of great political figures in Chinese history; the tour of famous spring and hometown famous figures of China; the tour of breeding grounds of Chinese revolution; the tour of worshiping ancestors; the tour of defense industry. ⑤Ratio of green space of uptown is higher than that of downtown. Ratio of green space of new city zone is higher than that of old city zone. The sequencing of area of different types of green space: other green space>attached green space>public park>nursery>green buffer. ⑥The sequencing of total area of five types of green space in the three cities is: Changsha>Xiangtan>Zhuzhou. The sequencing of per capita green space public park is: Xiangtan>Changsha>Zhuzhou. ⑦ problems of green space of the three cities: A. Total area, per capita area and quality of public space cannot meet the demand of people. B. The area of nursery cannot meet the demand of city construction. C. The area of green buffer is too small to improve the environment. D. The control of attached green space should be tightened andthe construction of attached green space should be guided. E. Importance should be attached to the protection and utilization of other green space. F. The configuration of different types of green space is not scientific enough.2.The layout of landscape of CZT: ①The sequencing of area of different types of green space is: Other green space>attached green space>public park>nursery>green buffer. This sequencing is in accordance with the status quo of green space of the three cities. The proportion of public park of Changsha (84.02%) is higher than that of Zhuzhou (75.93%) and Xiangtan (78.21%). The proportion of nursery and green buffer of Changsha (1.70%) is comparatively lower than that of Zhuzhou (2.85%) and Xiangtan (0.46%). The proportion of attached green space of Xiangtan is 19. 20% which is the highest of the three cities. Moreover, Xiangtan has the most number of patches (3785) and fragmentation degree, and the proportions of other types of green space are low. The green space pattern and space distribution of Xiangtan are bad. ② The proportion of average area of patch of CZT: Other green space is larger than other types of green space. Xiangtan has the highest proportion of average area of other green space (28. 70hm2). Zhuzhou has the lowest proportion of average area of public park (0. 6253hm2), nursery (1. 4819hm2) and attached free space (0.1948hm2). Changsha has the highest proportion of average area of nursery (4. 73hm2), moreover the total area of green space of Changsha is comparatively large. The self-sufficiency rate of seedling trees of Changsha is very high. ③The difference of fractal dimension of the three cities is not obvious. The fractal dimension of attached green space of Changsha is the highest. It shows that the shape of green space patch of Changsha city is more complicated than that of Zhuzhou and Xiangtan. It shows that people of Changsha turn every possible place into green space. The shapes of nursery and public park are well-regulated. The fractal dimension of nursery and public park is small. Changsha has the highest proportion of all 5 types of green space. It shows that the shape of different types of green space patch of Changsha is more complicated than that of Zhuzhou and Xiangtan. ④The fragmentation degree of nursery and green buffer of CZT is comparatively low. Of the threecities, Changsha has the highest fragmentation degree of nursery(0. 0374), Public Park(0.0112) and green buffer(0. 4900). It shows that in Changsha the green spaces mentioned above are greatly influenced by human interference. Landscape fragmentation in this region is serious. The fragmentation degree of attached green space of Xiangtan (0. 1919) is the highest among the three cities. The fragmentation degree of green space of Zhuzhou is comparatively low. The fragmentation degree of nursery of Xiangtan (51. 2356) is the highest because the number of this type of green space is small and they are sparsely separated in the city. The fragmentation degree of green buffer of Zhuzhou (14.3984) is the highest. It shows that there is not much green buffer in the city and the connectivity of them is not satisfying. ?The difference of landscape diversity in the region is not apparent. There is great difference between landscape diversity and the maximum variety. The landscape diversity of the region is not plentiful. Different types of green space separate evenly in Xiangtan, so no type of green space is in dominant place. Landscape dominance index of Xiangtan (0.9806) is the lowest. Changsha has the highest landscape fragmentation degree (0. 1080) and Zhuzhou has the lowest (0.0534). 3. Analysis of typical sectors of green space in CZT: 1) The pattern of landscape of Yueling Mountain:①The landscape resources of Yueling Mountain is of the first class. It suits the reputation of state-level famous scenic spot. The sequencing of landscape evaluation is: Lushan scenic spot, Juzhou scenic spot, Tianmashang scenic spot, Taohualing scenic spot, Shijialing scenic spot, Houhu scenic spot, Xianjiahu scenic spot, Zhaiziling scenic spot. The evaluation is objective and practical. It has similar number of natural landscape resources and cultural landscape resources. The rank of cultural landscape resources is remarkably higher than that of natural landscape resources and it has prestigious position in the region. ② Landscape pattern index shows that scenic spots of the region are evenly and widely separated. And each spot has is characteristics. Whole landscape diversity is high. Landscape dominance index of Woodland (30.73), garden plot (16.28) and cropland (24. 89) are in predominant position. Therefore, woodland, garden and cropland become the matrix of the whole scenic spot, But most of the spotsare greatly influenced by human activities. The main reason for that is they are located in outskirt. ?The sequencing of patch density in the region is: Water body>garden plot>detention surface>residential space>farmland>scenic spots>forest. ④ The landscape fragmentation index of Yueling Mountain is 0.00153 which is comparatively low. It shows that landscape fragmentation degree of the region is low. The fragmentation degree of water body (0. 14757) is the highest. Residential space and farmland have the second highest fragmentation degree which are 0. 04951 and 0. 02005 respectively. Water body and residential space have the highest inner landscape fragmentation degree. Other types of green space, especially scenic spots, detention surface, farmland and garden plot have comparatively lower inner landscape fragmentation degree. ⑤The sequencing of separation of scenic spot is: detention surface>garden plot>water body>farmland> residential space>scenic spot>forest. ⑥ The density of road in the region is 2. 199km/km2, the density of linear path in the region is 0. 9496km/km2, the density of ribbon road in the region is 1. 2494km/km2. The data above show that the region, especially the urban part, has developed road system. But the high density of road is adverse to the development of landscape resources. ⑦ The sequencing of area of different types of forest landscape in scenic spot is: mixed forest>orchard garden>board leaved forest > subtropical coniferous forest>oil tree forest. Of all the types of forest, mixed forest is 65. 28%; orchard garden is 25. 57%. Subtropical coniferous forest, board leaved forest, oil tree forest have very high forest landscape habitat fragmentation degree which are 0. 99291, 0. 97869 and 0. 99864 respectively. Orchard garden, mixed forest has comparatively low forest landscape habitat fragmentation degree which are 0. 74428 and 0. 34713 respectively. In the region, the area of subtropical coniferous forest, natural board leave forest and oil tree forest is small. There is only one subtropical coniferous forest patch. And natural board leave forest and oil tree forest are the same. But the area of mixed forest, orchard garden are much bigger than that of coniferous forest, board leave forest and oil tree forest. And they are not as greatly influenced by human activities as coniferous forest, board leave forest and oil tree forest. These are valuabledata for the landscape protection of the region: fractal dimension of orchard garden is 0.24963 which is related to the area and the number of the patch. The fractal dimension of mixed forest is 0. 16415 which is second highest of all. The area of mixed forest is the largest. And there are many mixed forest patches. Generally speaking, the fractal dimensions of all types of landscape are low. And they are greatly influenced by human activity. Orchard garden has the highest extension index (29. 6211), mixed forest has the second highest extension index (20.4917) and oil tree forest has the lowest extension index (4. 19089). There is only one oil tree forest patch in the region, and the area of it is the smallest of all types of forest. The shape of it is clear and neat. The forest diversity degree is 0. 9507, which is much lower than landscape diversity (1.94591). The evenness of forest landscape is 36.1382; several types of forest take predominant position in the region. The data mentioned above show that the forest diversity degree in the region is not high.2) The analysis of the layout of ecology and economic belt in Xiangjiang River shows that: ①The whole region is 46886hm2, 128. 0 kilometers in length. Different kinds of plants cover 22450. 4hm2; the coverage is 47.88%. Of all types of landscape patchse, farmland patch is 14070. 14hm2, which is 30.01% of the total area. It is also the largest patch. Forest is 16. 72%, public park is 1.12% and green buffer is 0.04%. According to the data, the number of farmland patch, forest patch, public park patch, and green buffer patch is 142, 77, 13 and 7. The number of farmland patch is 59.4% of the total number of all types of patches. The area of forest is 101. 7759hm2. The number of forest patch is 77, which is 32.2% of the total number of all types of patches. The number of green buffer patch is the smallest, and the area of it is 2. 6843hm2, which is also the smallest.As to the present condition of green space, Xiangtan has the largest area of forest, which is 43.96% of that of CZT. And the average area of forest in Xiangtan is 181. 33hm2. But the number of the patch is comparatively small. Changsha has the largest average area of farmland, while Xiangtan has the largest number of farmland patch. Changsha has the largest average area of public park, which is 46.1hm2. This is related to the green space in YuelingMountain—Tianma Mountain and the established riverside green belt. The sequencing of extension index and fractal dimension is: farmland>green buffer>forest>public park. Forest and farmland take a large proportion of the whole green space. Farmland is 32.67% of all the green space. Forest is the main part of green space. It is 16.72% of the whole area and 34.91% of the total green space. Public park is not enough and not evenly distributed. Riverside green belt is small, short and not efficiently connected to the green space in the urban area. There aren' t enough roads to connect the outskirt and the urban area in the region. The landscape space pattern index: the fractal dimension (1.0601) and extension index (1.7083) of Changsha is the lowest; the fractal dimension (1.2712), extension index (7.2571), fragmentation degree (0.0110), diversity index (1.1607) and (0.8852) of Xiangtan are the highest; the fragmentation degree (0.0097), diversity index (0.9081) and evenness (0.3345) of Zhuzhou are the lowest. (2) The type of landscape in the region is simple, the difference of landscape patches is not remarkable, the diversity index is low. Different types of landscape and different types patches are not evenly distributed in the region. Forest and farmland are in dominant position.4.The analysis of ecological function of green space in the region shows that: The whole green space in the region can produce enough O2 and consume enough CO2 to make both ends meet. But the urban green space cannot balance the CO2 consumption and O2 production. The whole green space in the region cannot absorb all the SO2 in the air. SO 2459296.53hm2 of green land should be produced to meet the need to get rid of the SO2 in the air.5. The analysis the vegetation of the region shows: (l)The study of natural vegetation shows: ①The consistence of natural vegetation: In the region there are 143 kinds of spermatophyte which is 68. 75% of the total number (208) ; 450 genera which is 37. 8% of the total number (1189) ; 86 species which is 20. 45% of total number (4239). In terms of distribution, there are 36 kinds of widely distributed spermatophyte which is 8.00% of the total number; 170 kinds of tropical spermatophyte which is 37.8% of the total number; 162 kinds of temperate zone spermatophyte which is 36% of the total number. It shows thatplants in the region are mainly subtropical. 82 genera can only be found in China and eastern Asia which is 18. 22% of the total number. 25 genera are widely distributed around the world which is 2.88% of the total number; lllgenera are distributed only in tropical area which 12.8% of the total number; 48 genera are mainly distributed in temperate zone which is 5.54% of the total number; 362 genus are mainly distributed in eastern Asia which is 41.75% of the total number; 321 genuses are distributed only in China which is 37.02% of the total number. From the data we can conclude that the last two genera are the dominant species of the region. There are all together 683 genera which is 78. 78% of the total number. (2) The characteristic of the type of vegetation in the region: the study of 108 sample areas shows that: The natural forest in the region can be divided into several types: ilex community; Castsnopsis carlesii community; Liquidambar formosana community; mason pine and Liquidambar formosana community; mahgrove community; Cyclobalanopsis glauca and Castsnopsis sclerophylla community; Castsnopsis sclerophylla community; holm oak community; Schima superba community; Michelia chapensis community; Liquidambar formosana, holm oak and ilex community; Cyclobalanopsis glauca community; Elaeocarpus japonicus community; Machilus pauhoi community; mason pine community. There are 15 communities all together. (3) The study of vegetation diversity in the region shows: the richness, diversity and evenness of vegetation pattern well reflected the complexity and habitat diversity of natural vegetation structure. The diversity index of the region is comparatively low because of human interference. The richness, diversity index and evenness index of arbor are lower than that of shrubbery and grass. Natural vegetation is in prophase of succession, so diversity index is low. With the evolution of natural vegetation, the richness, diversity and evenness of species will increase. But the figure will not as high as that of stable vegetation community. Quadrat distribute in scenic spot. And all indexes of vegetation community in well-protected region are higher than that of vegetation community in other areas. It is hard to find typical subtropical vegetation in the region. There is only a small piece of natural evergreen board leaf forest in the scenic spot and places near village. (4)The linageamong community species is: there are 5 pairs of species whose PC is no less than 70%. They are Castsnopsis sclerophylla and Cyclobalanopsis glauca, Elaeocarpus japonicus and Ardisia crenata, Clerodendrum cyrtophyllum and Rhus chinensis, Dicranopteris dichotoma and Loropetalum chinense, Dropteris dickinsii and Lophatherum gracile. There are 43 species whose PC are between 50% and 70%, 109 species whose PC are between 30% and 50%, 276 species whose PC are no more than 30%. The species with high PC are very common in CZT region. (5) In CZT, the proportion of subtropical evergreen broad leaf forest, which is the top community in the region, is very low. And they distribute in scenic spot. While the proportion of the community which is in the early stage of evolution is comparatively high. (6) Bamboo forest landscape: there is little natural bamboo forest landscape in the region. They mainly distribute outside village, and are mainly composed of Phyllostachys heterocycla forest and Phyllostachys bambusoides.The study of the pattern of manmade forest in the region shows: (1) The constitution of urban landscape: spermatophyte in the region is composed of 86 families, 183 genera, and 266 species. Gymnosperm in the region is composed of 9 families, 20 genera, and 31 species. Angiosperm in the region is composed of 77 families, 163 genera, and 235 species. Of all the plants, arbor is 44%; shrubbery is 34. 2%; herbage is 16%; liana is 4. 1%; hydrophyte is 0. 7%. Of all the landscape plants, 25% are foreign plants. This is one of the characteristics of the constitution of vegetation in the region. But domestic plants are in dominant position. And this should be the trend of development of landscape in the region. (2) The pattern of vegetation: 211 samples of urban green space vegetation and 682 kinds of vegetation arrangements are studied in research. The findings of the research are as follows: ? There isn' t any established principle and system to be used as reference for manmade vegetation. The article consulted China Vegetation (1980). And it is based on the principle of coenology—ecology; cited the former study of structure and type of vegetation community, life form of dominant species as evidence. According to the article the manmade vegetation of CZT can be catergrized into 3 kinds, 8 patterns, 24 groups and 213 kinds of arrangement. According to thearrangement, function, landscape of manmade vegetation community the article also proposed 10 optimization patterns which can be applied to cities in Yangtze River delta. (2) The chief characteristics of plant community in CZT are: The utilization ratio of local plants is high, but the variety of local plants used is not large. Shrubbery is excessively used. The structural level of vegetation community is comparatively simple. The disparity of the quality of plants is remarkable. (3) The study of diversity of plant community in the region shows: ①To some extent, the degree of diversity of vegetation community will increase with the increase of area of green space. Local species show high degree of diversity. ② Comparatively speaking, the diversity degree is comparatively low and the richness of natural vegetation and manmade vegetation are not satisfying.6.The study of public awareness of the importance of green space in the region shows: 1) The public awareness of the importance of green space is greatly influenced by culture and environment itself, the level of economic complexity, management system, the existing circumstances of environmental protection, the propaganda and education of environmental protection, etc. Of all the factors, the management of green space and the promotion of people' s environmental protection awareness by mass media have the most direct influence. 2) Of all different professional groups, cadres who have good educational background have higher environmental protection awareness, vice versa. Individual elements have complex influence on public environmental awareness: people with better education background are more sensitive to the protection of green space. As to green space construction, people with college degree are less sensitive than people with senior high school and technical secondary school degree. The general publics believe that of all the factors, social culture and environment and level of economic complexity is 44%; human interference is 39%; culture is 10% and natural environment is 7%. The general publics have unanimous opinion on the issue. 3) The general publics believe that the construction of green space should prior to economic construction. As to urban green space, public think that matters such as manmade damage and flaw in management should not be overlooked.They acknowledge the great improvement in urban green space construction and point out that the growth of urban green plants is not satisfying. 4) Most people think that public participation is vital to the construction of urban green space. Many of are participating in the activity. Other people think that the quality of green space depend on the management of government.7. The systems framework of green space in CZT: (1) Environment landscape of CZT is composed of mountain forest, farmland, water body and cities and towns. The sequencing of area is: mountain forest >farmland >water body >cities and towns. Therefore, the framework of green space of CZT should base on its geographical factors (mountain forest, farmland, water body, cities and towns). The layout of green space should be guided by the principle: green space encircling cities and cities surrounding green space. (2) Green and rolling downy hills, blue water, farmlands interspersed with ponds are the basic regional scene of CZT. As a whole, the character of green space landscape of CZT can be summarized as: hill, green hills and blue water, and famous city. (3) The forest of the region is the fundus of the landscape; ecotones between cities and villages are medium shot; green space landscape of built-up area of cities is close shot; rivers, roads and mountains are corridors. The three cities distributed around Xiangjiang River, forming a triangle. (4) The framework of green space landscape of CZT is: three cities and one green star and a green space ecotone and a forest ecology system.The green space in the region should be blended into ecological system. In order to attain the object, from the vegetation ecological point of view, three vegetation restoration methods and six plant landscape patterns are proposed.The study is supported by the provincial key scientific and technological project (Hunan planning commission [2001] No.659). It aims at the problems arose in the course of regionalization of CZT. For the first time from the regional point of view, it unfolds a overall and systematic study of Natural landscape resources, landscape pattern, ecology function, vegetation landscape, and public awareness. It is important for the sustainable development of regional environment of CZT. It also supply a gap for the study...
|
PDF Full Text Request