Thousands of Flowers Garden Integrated into Beautiful Mountains and Rivers—Space Deduction from Planning to Implementation of the International Horticultural Exhibition 2019, Beijing, China

YAN Wei, HOU Shuang, WANG Xian

Under the new era background that emphasizes the concept of ecological civilization development, as an international window that shows the value pursuit and construction achievements of human ecological civilization in the 21stcentury, in the landing process of the concept plan and the implementation plan, the International Horticultural Exhibition 2019 Beijing China (hereinafter referred to as "Beijing Expo") has set up a multi-disciplinary and cross-disciplinary team to meet the great challenge of large exhibitions and explore the harmonious reconstruction of artificial environment and nature from different professional perspectives to show the unique "harmony of human with nature" environmental system in China to the world.

1 Site Opportunities and Challenges

Yanqing District, surrounded by mountains on three sides with one river running through it, is chosen as the site of the Expo. Haituo Mountain is in the north while Badaling Great Wall is in the south, and Guihe River runs through the garden. The landscape pattern sets the best environment background for the space organization, and the cultural feelings of "homesickness aroused from the view of mountains and waters" have a natural support, which corresponds to the expectations of mountains and rivers and ideal homes in the process of urbanization in China, and provides a good space carrier for interpreting the theme of "Live Green, Live Better". In addition, as the expo of the world's highest level, the scale of participants and visitors is large and the demand for exhibition, service and transportation is huge. How to achieve a safe, comfortable and pleasant viewing experience and express the charm of Chinese cultural space is the biggest challenge in spatial planning.

2 Inspiration from Conceptual Scheme Collection

In order to widely absorb the advanced planning and design concepts at home and abroad, the organizer globally collected the best solutions that integrated the huge exhibition functions into the natural environment in 2014. The competition plans had their own characteristics. There were plans such as introducing Guihe River to the garden and displaying the exhibition along the river bank; and reshaping the original forests and farmland to enjoy the surrounding landscape in a rural vision; and more plans were of reshaping the landscape space in the garden and the adaptation to local conditions outside it.

2.1 Inspiration origin of the site adaptation to local landscape—nature moving point

The award-winning proposal entitled "Mountain and Rivers Meet for Blooming Flowers" jointly submitted by Beijing Institute of Landscape and Traditional Architectural Design and Research, Beijing Tsinghua Tongheng Urban Planning and Design Institute and Beijing Urban Construction Design & Development Group Co., Ltd. was chosen as the basis for the final planning. The team entered the site many times to explore the spiritual space where the nature of mountains and rivers moved people's hearts. Fortunately, the team soon found the wonderful place that connects the natural landscape, that is, the turning of Guihe River. Here, there is the longest water-viewing corridor to the west, and the north is Guanmao Mountain with pretty and unique shapes. The beautiful mountains and rivers form a Panoramic pictureand touch our hearts directly. This is the inspiration origin of the space organization –the nature moving point, completely corresponding to the spiritual support of the expo concept of "integrating horticulture into nature and touching souls with nature".

2.2 Space framework built by landscape corridor

The nature moving point and Guanmao Mountain form the longest north-south landscape corridor. Extending it to the southern boundary of the garden, the main entrance and exit of the garden and the landscape horticultural axis are established; combined with the comprehensive traffic analysis, another major entrance and exit is set up at Yankang Road, which is connected to the nature moving point and opposite to Haituo Mountain, forming the international horticultural axis. The establishment of two axes provides the space carrier for the introduction of the large landscape pattern into the garden. The traditional Chinese gardening art is inherited, and varying scenery can be enjoyed when one walks and the straight axis is softened. In order to enhance the site identification, in addition to the axial guidance, the main pavilions will play the role of landmarks, giving the public space of each area different features and characteristics to enrich the exhibition space.

3 Spatial Distribution during the Plan Integration

When integrating plans, as one of the core teams, inspired by each plan, we reexamined the site and planned to form the planning structure of "one core, two axes, three belts and multiple zones" by adopting Guanmao Mountain, Haituo Mountain and the Great Wall far away and Guihe River nearby, organically integrating hundreds of exhibition gardens and five main pavilions with landscapes.

One core: It is planned to use the existing fish ponds to expand and form "Guirui Lake", and the earth would be used to build the "Tiantian Hill" nearby, which is the ingenious connection for introducing the viewing corridor of mountains far away to the garden. "Pavilion of Yongning" will be built at the mountain, which is the best place to enjoy the beautiful scenery of the whole garden. Tiantian Hill and Guirui Lake are integrated into the beautiful landscape through the nature moving point, becoming the core landscape area. The Performance Center, Lawn Theater, and China Pavilion will be built around Guirui Lake, forming harmonious scenery that "connects the world with one core, and experiences the feelings of mountains and rivers".

Two axes: The first is the landscape horticultural axis, which goes through the Ritual Gate, China Pavilion and Tiantian Hill and is opposite to Guanmao Mountain, showing the oriental romantic charm with the theme of "Feng(Airs of the States), Ya (Hymns), and Song (Eulogies)"; and the second is the international horticultural axis that passes through the Boulevard Gate and International Pavilion and faces Haituo Mountain, depicting the world wonders.

Three belts: In order to facilitate the evacuation of people, Life Experience Pavilion and Plant Pavilion are arranged on both sides of the garden as the core of the east and west exhibition areas. The spatial layout presents a pattern of prominent emphasis and relatively balanced layout, thus forming three east-west ribbon spaces. The northern part is the "Guihe Ecologic Recreational Belt" relying on the natural scenery of the Guihe River; the central part is the "Horticultural Life Experience Belt" integrating tour and dining services; and the southern part is the "Horticultural Industry Development Belt" with a variety of horticultural industries.

Multiple zones: The "one core, two axes, and three belts" build the public space system of the garden and divide the site into multiple exhibition zones. Five functional zones are determined in corresponding to the subthemes: Chinese Exhibition Zone, International Exhibition Zone, Life Horticulture Exhibition Zone, Education and Future Exhibition Zone and Spiritual Homestead Exhibition Zone.

4 Drawing Deliberation & On-site Polishing in the Implementation Stage

Entering into the landing stage, the most critical is detailed deliberation of the drawings and the repeated on-site polishing. The most perfect concepts and ideas need to be realized through design drawings and engineering construction.

4.1 Plan positioning of the general layout and landform refinement

During the alignment of the general layout, the team entered the site, reviewed and checked the planned road network and vertical distribution with the current vegetation and terrain, striving to maximize the preservation of the site's ecological resources. In areas with better ecological background, the protection scope is strictly defined to control the size of tourists. More than 50,000 big trees in the current situation have been preserved. The trees along the original villages and fields are fully integrated with the planned road network and public space to maximize the comfort of the boulevard. The original ponds combined with the sponge park concept are effectively utilized. The size and shape of water surface, the elastic shoreline and the mountain and river ratio of the main ornamental surface are repeatedly studied according to the demand for storage capacity in the rainy season and the self-purification demand of the lake. Everything revolves around the design goals of minimal disturbance, best function, optimal effect and integration into nature.

4.2 Core landscape deliberation and site memory retention

Walking out of the iconic pavilion, China Pavilion, tourists will see the core scenery directly. The foreground is Guirui Lake while the background is the continuous Jundu Mountains. The design uses the poplar trees near the original fish pond to create the Green Poplar Isle, which means that "retaining these green poplars is to retain the root of the site, retaining the memory of the hometown". In order to solve the altitude difference between the trees and the lake, taking Jundu Mountain as the prototype, artificial hills are built to correspond to Haituo Mountain and Guanmao Mountain, introducing the landscape of lower mountains of Yanshan Mountains with regional characteristics into the garden. A rainbow-shaped bridge made of traditional Chinese wooden arch structures (the woven arch) is built over the lake to connect with Green Poplar Isle. On the other side of the bridge, a modern Chinese-style slope crest architecture provides striking key point to the whole picture. Since it is located in the west and faces the east and suitable for watching sunrise, it is named as "Sunrise Hall", meaning "keeping up every day through introspection". The three nodes of Green Poplar Isle, Rainbow Bridge and Sunrise Hall connect the mountains and rivers and lakes, forming a grand landscape picture with texture. It is an important thinking to protect and utilize the original site texture and to integrate it into the landscape in the design and implementation process, thus bringing the old willows along the "Colorful Water Fall", making it more humanistic; bringing the later unique "Silkroad Garden", utilizing the original triangle clay platform on site making the garden have the Great Wall background. The romanticdesign thinking based on the site random scene makes the landscape of Beijing Expo more local and retains the artistic conception of homesickness.

5 Conclusion

Every planning and design stage is a process of recognition of the natural environment of the site, rearrangement of the needs of the expo organization, recreation of the plan and re-exploration of the harmonious development between human and nature at different depths, scales and levels. Aiming the timeliness and comprehensive characteristics of the expo, the design team not only provides drawings, but also does more field work to implement the design intention according to the actual conditions such as site conditions, technical processes, materials, ecological needs, construction timing, and extreme weather, and to ensure the final implementation of the concept of integrating the garden construction into the natural environment, staying true to the planning mission.

The deduction process from planning to implementation is to explore the green development mode and lifestyle with the new era characteristics of China through the practice of the construction of the Expo and to provide new ideas and reference for the correct handling of the relationship between economic development and ecological environment protection for the urban construction in China and the construction of urban and rural ecological civilization. 2019 is the 70thanniversary of the founding of the New China, and it is the eve of China's final victory in building a well-off society in an all-round way. The holding of Beijing Expo will be an important window to show the new achievements of ecological civilization construction, and it is a vivid practice of building a beautiful China. It is of great significance and far-reaching influence.