Doctor rain | how to design a sustainable sponge City

The design of sponge city should follow the basic principles of ecology

Although the system of ecology is huge and all inclusive, its principles mainly include three key points: Bearing capacity, Relationship and Sustainability.

Firstly, any ecosystem has a certain Bearing capacity. Things develop healthily within the Bearing capacity, and beyond the Bearing capacity, there will be imbalance. In the design of sponge City, the balance of water resources Bearing capacity, water environment Bearing capacity, water ecological Bearing capacity and soil Bearing capacity should be ensured.

Secondly, in the ecosystem, everything are interrelated, which directly affects the formation and development of things. In sponge city design, we should correctly deal with the relationship between water and soil, water and vegetation, water and land, and spatial pattern.

Finally, achieve sustainability of the system. An important criterion for the success of sponge city design is its sustainability. A scientific and reasonable design must be environmentally, ecological and sustainable. Ecology must be sustainable and cannot be unsustainable. A sustainable sponge city design must comply with the following ecological principles.

1、The Principle of Ecology preference

When planning sponge City, we should put the protection of ecosystem in the first place. When ecological interests conflict with other social and economic interests, we should first consider the needs of ecological security and meet ecological interests.

First, investigate the background of regional ecosystem and local ecosystem, and determine the priority protection object without damaging the local ecosystem. Sponge city should emphasize the overall function of ecosystem. In the city, ecosystem has many functions, the social function, economic function, supply function, support function and landscape function. ecosystem should be based on ecological function to form an ecological priority, social economic natural composite ecosystem.

2、The principle of protecting the original ecosystem of the city

It is the basic requirement of sponge city construction to protect the original water ecological infrastructure such as rivers, lakes, wetlands, ponds and ditches to the greatest extent and reduce the impact of urban construction on the original natural environment as much as possible. Take ecological, decentralized and small-scale source control measures to reduce the impact and damage of urban development on the natural ecological environment, and retain the original green space and wetland to the greatest extent. Urban development and construction shall protect water ecological sensitive areas, give priority to the use of natural drainage system and low impact development facilities, realize rainwater collection, infiltration, purification and sustainable water cycle, improve the self-healing ability of water ecosystem, maintain the natural hydrological characteristics before urban development, maintain the good ecological function of the city, delimit the urban blue line, and Lakes and other water ecological sensitive areas are included in the scope of non construction land in the urban planning area and connected with the urban rainwater pipe and canal system.

3、The principle of Multistage layout and relative dispersion

Multi level layout and relative dispersion means that in the process of sponge city planning, we should pay attention to the role of small-scale regional ecological land such as communities and neighbors, form a variety of green patches according to their own properties, reduce construction costs, decompose runoff pressure and manage rainwater from the source. Green space and wetland should be divided into multiple levels such as city, area and neighborhood. Through decentralized and ecological low impact development measures, the objectives of total runoff control, peak control, pollution control and rainwater resource utilization should be realized to prevent river erosion, water and soil loss and water pollution in urbanized areas. Maintain the integrity of urban water system structure, optimize the layout of urban river and lake water systems, and realize natural and orderly discharge and storage.

4、Principle of adjusting measures to local conditions

The development objectives and scientific planning and layout should be reasonably. According to the local water resources, geographical conditions, hydrological characteristics, water environment protection and local waterlogging prevention and control requirements. Low impact development facilities such as sunken green space, rainwater garden, grass planting ditch, permeable pavement and multi-functional regulation and storage shall be reasonably selected. In addition, in species selection, native plants and flood resistant plants should be selected to avoid long-term immersion of plants, which will affect the normal growth of plants and the purification effect.

5、The principle of System integration

Based on the concept of sponge City, system integration not only includes the integration of ecosystem and other systems (road transportation, buildings and municipal administration, etc.) in traditional planning, but also emphasizes the relationship integration between various components within the ecosystem. The ecological infrastructure such as natural water body, artificial water body and infiltration technology should be considered as a whole, and then combined with the design of urban drainage pipe network, all parts involved in rainwater management should be integrated to make it an interconnected organic whole, so that rainwater can infiltrate, store, utilize and discharge smoothly through a variety of channels, so as to reduce the damage caused by rainstorm to the city.