“碳中和”是全球熱點(diǎn)議題，其目標(biāo)設(shè)立為后疫情時(shí)代推動(dòng)全球綠色復(fù)蘇，實(shí)施結(jié)構(gòu)性減排提供了契機(jī)。在風(fēng)險(xiǎn)與機(jī)遇并存的當(dāng)下，人類命運(yùn)共同體聯(lián)系日益緊密，“碳中和”發(fā)展亦是回應(yīng)時(shí)代新問(wèn)題新挑戰(zhàn)的重要目標(biāo)。評(píng)估顯示城市在全球排放量中所占的份額超過(guò)70%，是全球碳排放的重要貢獻(xiàn)者。隨著預(yù)期的人口增長(zhǎng)，未來(lái)城市減排是實(shí)現(xiàn)氣候目標(biāo)的關(guān)鍵解決方案。

早期的人居環(huán)境即蘊(yùn)含“綠色低碳、永續(xù)發(fā)展”理念。古代西方的庭院中多種植草藥和水果，人們挖掘它們的食用、藥用、美學(xué)等功能，并將各種植物功能轉(zhuǎn)化為生活中所需的元素，這樣可以降低生產(chǎn)成本，并極大地減少食品消費(fèi)、日常生活的碳足跡；同時(shí)，精確計(jì)算不同階段不同植物種類的水肥量，注重對(duì)植物原始狀態(tài)的維護(hù)。中國(guó)江南地區(qū)傳統(tǒng)院落中，“蟹眼天井”的設(shè)置不僅解決室內(nèi)空間的采光通風(fēng)問(wèn)題，還可以形成煙囪效應(yīng)調(diào)節(jié)熱環(huán)境，通過(guò)合理利用自然條件減少了大量能源消耗，并結(jié)合園林營(yíng)造形成了經(jīng)典的“尺幅窗”“無(wú)心畫”景致。云南哈尼梯田設(shè)計(jì)了森林、村寨、梯田、水系“四素同構(gòu)”的循環(huán)系統(tǒng)，維護(hù)了鄉(xiāng)土物種資源和生境類型的多樣性，形成了穩(wěn)定可持續(xù)的生態(tài)農(nóng)耕模式，成為可持續(xù)低碳稻作人居環(huán)境的典范。

碳中和的目標(biāo)如何在空間場(chǎng)所上實(shí)現(xiàn)？如何為數(shù)量化的目標(biāo)賦予形式？這對(duì)“雙碳”背景下的設(shè)計(jì)應(yīng)對(duì)提出了新的挑戰(zhàn)。風(fēng)景園林師是系統(tǒng)設(shè)計(jì)師，以公園、林蔭道、雨水花園和生境營(yíng)造等形式整合綠色基礎(chǔ)設(shè)施作為設(shè)計(jì)策略，不僅可以減碳增匯，還可以管理雨洪、降低城市熱島效應(yīng)、增加生物多樣性以及改善健康和福祉。同時(shí)，設(shè)計(jì)連續(xù)舒適的城市步行環(huán)境和綠道系統(tǒng)，整合安全、無(wú)障礙的行人和自行車道，倡導(dǎo)公共交通優(yōu)先，這對(duì)減少城市能源需求和降低碳排放、實(shí)現(xiàn)更廣泛的城市氣候目標(biāo)意義重大。

“雙碳”背景下的設(shè)計(jì)應(yīng)對(duì)策略是要在充分尊重利用自然的生態(tài)智慧基礎(chǔ)上，建立全面的知識(shí)框架，探索減排增匯在空間上的實(shí)現(xiàn)路徑。通過(guò)新的設(shè)計(jì)方式實(shí)現(xiàn)碳中和目標(biāo)所需的新一代公園、綠地、步行騎行交通和公共基礎(chǔ)設(shè)施，將不同的城市生態(tài)系統(tǒng)融入綠地與公共空間體系中以最大化儲(chǔ)存碳，提高城市應(yīng)對(duì)氣候變化帶來(lái)的各類風(fēng)險(xiǎn)的能力，實(shí)現(xiàn)城市綠色有機(jī)更新；在這個(gè)過(guò)程中，需要風(fēng)景園林師科學(xué)地考慮各類生態(tài)系統(tǒng)的區(qū)域配置和與各類服務(wù)功能的結(jié)合。在面對(duì)碳循環(huán)失衡的問(wèn)題時(shí)，更加重視城市綠地全生命周期階段的碳平衡狀態(tài)，挖掘氣候變化減緩與適應(yīng)之間的協(xié)同效應(yīng)，強(qiáng)化綠色生態(tài)空間在節(jié)能減排、碳匯增效、生物多樣性保護(hù)、城市更新發(fā)展等工作中發(fā)揮的重要作用。

在全球氣候變暖的大背景下，碳中和與生態(tài)環(huán)境是未來(lái)長(zhǎng)期的研究熱點(diǎn)與重大挑戰(zhàn)，如何發(fā)揮多學(xué)科交叉優(yōu)勢(shì)，創(chuàng)新設(shè)計(jì)方法與技術(shù)，進(jìn)一步拓展與延伸生態(tài)賦能碳中和的深度，是風(fēng)景園林學(xué)科在實(shí)現(xiàn)碳中和目標(biāo)中的重大使命，也是設(shè)計(jì)師重新認(rèn)識(shí)自然、思考可持續(xù)發(fā)展新范式，為未來(lái)人居環(huán)境建設(shè)描繪更加生態(tài)、宜居、低碳藍(lán)圖的宏觀愿景。

Carbon Neutrality and Design Strategies

Being a global hot-spot issue, carbon neutrality aims to provide an opportunity for promoting global green recovery and structural to promote global green recovery and structural emission reduction in the post epidemic era.In face of co-existence of risks and opportunities today,humanity is increasingly a community with shared future.Carbon neutrality is an important goal in response to new issues and challenges in the new era. Estimates show that cities are significant contributors that account for more than 70%of global emissions. With the expected population growth,urban emission reduction will be the key solution to achieving climate goals.

The early living environment had carried the concept of “green, low-carbon and sustainable development”. Herbs and fruits were planted in ancient Western courtyards. People explored their esculent, medicinal and aesthetic properties,and transformed plants into needed elements needed in life based on their properties, thus lowering production costs and greatly reducing carbon footprint of food consumption and daily life. At the same time, the amount of water and fertilizer needed by different species of plants at different stages was calculated accurately, with emphasis on maintenance of their original state. In the traditional courtyards in Southern China,“crab eye patios” not only solved the lighting and ventilation problems in indoor space, but also created a chimney effect to regulate the thermal environment, which reduced a large amount of energy consumption through rational utilization of natural conditions, and formed classic enframed sceneries through garden design. Hani Terrace in Yunnan province was designed with a four-element isomorphic circulation system consisting of forest, villages, terrace and water. It maintained the diversity of local species and habitat types and formed a stable and sustainable ecological farming model, being model of sustainable low-carbon rice-farming human settlements.

How to achieve carbon neutrality in spaces and places?How to create a form for quantitative goals? This poses new challenges to the design under the background of carbon peaking and carbon neutrality. Landscape architects are system designers. By following the design strategies of integrating green infrastructure through creation of parks, boulevards,rain gardens and habitats, they can help not only reduce carbon emissions and increase carbon sinks, but also manage rains and floods, reduce urban heat island effect, increase biodiversity and improve health and well-being. Furthermore,the design of a continuous and comfortable urban pedestrian environment and greenway system, the integration of safe and barrier-free pedestrian and bicycle lanes, and encouragement of priority of public transport are of great significance to reducing urban energy demand and carbon emissions, as well as achieving broader urban climate goals.

In the context of carbon peaking and carbon neutrality,the design strategies should aim to establish a comprehensive knowledge framework and explore the path to carbon emission deduction and increase of carbon sinks in space based on the fully respect to and utilization of the ecological wisdom of nature. New designs will help probe into the requisite new generation of parks, green spaces, pedestrian and cycling transportation and public infrastructure for carbon neutrality and integrate different urban ecosystems into the green spaces and public space system to maximize carbon storage and improve the ability of cities to cope with risks brought by climate change, thus realizing organic renewal of cities. In this process, landscape architects are required to scientifically take into account regional configuration of various ecosystems and combination of various service functions. In view of the imbalanced carbon cycle, it’s required to pay more attentions to the carbon balance in the whole life cycle of urban green space, identify the synergistic effect between climate change mitigation and adaptation, and strengthen the important role of green ecological space in energy conservation and emission reduction, carbon sink efficiency, biodiversity protection,urban renewal and development, etc.

Against the backdrop of global warming, carbon neutrality and ecological environment will be long-term research hot spots and major challenges in the future. As to how to give full play to the advantages of interdisciplinary,innovate methods and techniques in design practice, and further deepen and extend the depth of ecology-empowered carbon neutrality, it is a major mission of landscape architecture in achieving carbon neutrality, as well as a macro vision of architects in re-understanding of nature,consideration of new paradigm of sustainable development,and depicting a blueprint of more ecological and more livable low-carbon living environment in the future.

Editor-in-Chief: Professor ZHENG Xi

April 28, 2022