邊蘭春

當(dāng)前，我國城市發(fā)展方式已經(jīng)從增量開發(fā)轉(zhuǎn)向存量更新，追求城市空間環(huán)境品質(zhì)的不斷提升，建設(shè)創(chuàng)新、協(xié)調(diào)、綠色、開放、共享的城市，已經(jīng)成為實現(xiàn)人居環(huán)境高質(zhì)量發(fā)展的迫切要求。隨著城市的發(fā)展，納入到城市空間環(huán)境中的自然棲息地也在不斷流失，休憩空間嚴(yán)重不足。因此，宜人開放空間的塑造已經(jīng)成為城市設(shè)計的核心內(nèi)容之一，也是評價城市宜居性的重要考量標(biāo)準(zhǔn)。

水是城市的生命線，世界上很多城市都是因水而生、伴水而榮。河湖水體、綠色空間構(gòu)成了城市藍(lán)綠生態(tài)空間網(wǎng)絡(luò)的主要部分，與之緊密相關(guān)的濱水空間也因承載了城市的自然生態(tài)、聯(lián)結(jié)起城市的休閑生活、孕育出城市的特色與活力，最終見證了城市的發(fā)展變遷，并被持續(xù)塑造成為城市的一道道靚麗風(fēng)景。

長期以來，我們對城市中心地區(qū)繁榮活力的關(guān)注，遠(yuǎn)遠(yuǎn)超過了對城市邊緣地區(qū)生態(tài)和文化景觀價值的認(rèn)識。城市邊緣地區(qū)是城市和鄉(xiāng)村的交界地帶，一方面，這一地區(qū)具有良好的生態(tài)環(huán)境本底，生態(tài)空間與城市空間融合的潛力巨大；另一方面，在城市擴展過程中，這一地區(qū)又往往因為城鄉(xiāng)用地混雜、管理相對薄弱，使生態(tài)空間與城市空間融合發(fā)展面臨很大挑戰(zhàn)；同時，另一個值得我們反思的問題：我們長期以來只把這些地區(qū)看作空間品質(zhì)不佳的“城鄉(xiāng)結(jié)合部”，忽視了這些地區(qū)中開放空間與城市的生態(tài)關(guān)聯(lián)，忽視了社區(qū)發(fā)展中的生活互動，忽視了濱水營造中的景觀與活力。針對這樣的地區(qū)，如何通過“生態(tài)修復(fù)和城市修補”帶動生態(tài)資源的有機整合、交通體系的系統(tǒng)梳理、生活設(shè)施需求的細(xì)微體察，加強多元城市功能的高效組織，實現(xiàn)城市邊緣區(qū)的高質(zhì)量發(fā)展，應(yīng)該成為當(dāng)下城市更新行動中亟待關(guān)注的重要議題之一。

北京清河濱水空間也許就是未來城市設(shè)計與城市更新的一個典型案例。清河濱水綠廊是海淀北部高新科技發(fā)展區(qū)與南部城市密集區(qū)形成有機銜接的重要地區(qū)，更是西山風(fēng)景區(qū)與東部城市建設(shè)區(qū)形成東西聯(lián)系的重要走廊。清河從清朝初年延續(xù)至今，伴隨著“三山五園”的建造和這一地區(qū)的演進(jìn)發(fā)展而逐步發(fā)育成熟。清河是一條自然的河流，自西山向東匯入溫榆河；清河是一條文化的河流，串聯(lián)歷史的三山五園和現(xiàn)代城市創(chuàng)新聚集區(qū)中關(guān)村科技園、國際體育文化承載地奧林匹克森林公園；清河還是一條生活的河流，沿線地區(qū)已經(jīng)從“城鄉(xiāng)結(jié)合部”逐漸演進(jìn)為居民生活重要的休憩場所和交通走廊。歷史上的清河與北京自然水系的形成演變密切相關(guān)，現(xiàn)在的清河沿線，既有世界文化遺產(chǎn)頤和園，也有亟待更新改造的“城中村”，河流綠地、交通道路、居住社區(qū)、單位大院多種要素相互交織，錯綜復(fù)雜。探究清河以及因之興衰的聚落地理文化、功能認(rèn)知和發(fā)展愿景，不僅可以更好地認(rèn)知城市歷史、探索“三山五園”的遺產(chǎn)保護(hù)，還可以為這一地區(qū)的生態(tài)景觀修復(fù)和文化風(fēng)景營造，奠定重要的基礎(chǔ)。

本期專輯收錄了清華大學(xué)建筑學(xué)院團隊的6篇研究論文，他們基于多年擔(dān)任清河沿線街鎮(zhèn)責(zé)任規(guī)劃師高校合伙人過程中的觀察和思考，從歷史、景觀、環(huán)境、交通、城市、社區(qū)、治理等多個維度展開對清河的研究。前3篇清河認(rèn)知板塊，從歷史地理視角梳理了北京清河的演變（鐘舸等），厘清了對清河沿線地區(qū)城市功能特色的認(rèn)知（黃鶴等），并從大城市邊緣區(qū)發(fā)展的視角探討了海淀清河段濱水空間發(fā)展的矛盾與問題（陳宇琳等）。后3篇濱水空間更新整治板塊，結(jié)合清河的空間現(xiàn)狀和社區(qū)結(jié)構(gòu)提出了濱水空間綜合整治要素及治理導(dǎo)向（王英等），分析了城市邊緣區(qū)濱水綠道的使用模式與人群需求（陳宇琳等），并開展了面向濱水空間整治的道路交通可達(dá)性分析和提升策略研究（梁思思等）。本專輯的研究成果在清河濱水地區(qū)的城市設(shè)計實踐課題中還得以不斷深化，以期為清河濱水空間的更新整治提供多視角的解讀，同時也為我國大城市城鄉(xiāng)交界地帶濱水空間城市設(shè)計與城市更新中的精細(xì)化治理提供參考。

大約三年前，擔(dān)任該地區(qū)責(zé)任規(guī)劃師高校合伙人的清華大學(xué)團隊曾對清河綠廊規(guī)劃實施工作發(fā)出倡議，清河濱水地區(qū)環(huán)境品質(zhì)的提升應(yīng)以系統(tǒng)性的研究為基礎(chǔ)、以專題性的規(guī)劃為前提，依托多學(xué)科融合的研究實踐平臺，制定城市設(shè)計導(dǎo)則指引和行動指南，不斷探索參與式規(guī)劃的實施路徑和方法。為了發(fā)揮清河濱水綠廊地區(qū)獨特區(qū)位優(yōu)勢，充分依托本地區(qū)生態(tài)景觀資源條件，面向社區(qū)生活的需求，制定整體框架、有序分段實施、注重持續(xù)提升，以人為本，實現(xiàn)“讓風(fēng)景融入城市，讓生活走進(jìn)風(fēng)景”的美好愿景。□

（2019年10月17日清華大學(xué)高校責(zé)任規(guī)劃師團隊成員發(fā)起了《清河綠廊規(guī)劃倡議書》。2020年5月北京市規(guī)劃和自然資源委員會海淀分局組織開展了面向清河濱水地區(qū)空間環(huán)境的“清河行動”，并組織清華大學(xué)團隊與中國城市規(guī)劃設(shè)計研究院合作完成了《清河兩岸綜合整治提升規(guī)劃》。本專輯部分成果根據(jù)清華團隊負(fù)責(zé)的部分專題成果深化完成。在此向北京市規(guī)劃和自然資源委員會海淀分局和中國城市規(guī)劃設(shè)計研究院，以及支持參與這項工作的同仁一并致謝！）

Currently, the pursuit for innovative, harmonious, green, open and shared cities has become an urgent agenda for achieving high-quality development of human environment in China. After decades of development, the natural habitats are continuously disappearing in cities, and there is a serious shortage of open space. The pleasant open space has become one of the core elements of urban design and an important consideration in evaluating the liveability of cities.

Water is the lifeline of a city. Many cities in the world were born from water and thrived with water. Water bodies and green spaces are important elements of the city's ecological system. They bear the city's leisure life, nurture the characteristics and vitality of the city, and witness the development and changes of the city.

For a long time, we have paid little attention to the urban fringe, i.e., urban-rural areas. On the one hand, these areas have a good ecological background with great potential for integrating ecological spaces and urban spaces; on the other hand, in the process of urban expansion, these areas often face huge challenges in the integration because of disordered urban-rural land uses and relatively weak management. At the same time, another issue deserves our reflections – we have neglected the ecological connections, the social interactions, the landscape vitality of these urban-rural areas, and they have been in poor spatial quality for a long time. As a matter of fact, it is among the important issues in the urban regeneration actions that requires urgent attention regarding how to achieve high-quality development through ecological restoration, organic integration of ecological resources,systematic sorting of transportation system, investigation of facilities requirement, and high-efficient organisation of urban functions.

The waterfront space of Qinghe River is probably one of the most typical cases in urban design and urban regeneration in the future. Its landscape corridor connects the Haidian High-tech Development Zone in the north with the urban dense area in the south, as well as Xishan Scenic Area in the west with urban areas in the east. Qinghe River is a natural river, from Xishan Mountain to Wenyu River; it is a cultural river, bearing the history of royal gardens of Qing Dynasty and the Olympic Forest Park and Zhongguancun Tech-Zone; it is also a living river, evolving with important leisure places and traffic lines for the neighbourhood and communities. To explore the geographical culture, the functional perception and the vision of Qinghe River with its rise and fall will not only enable us to better understand the city's history, the conservation of royal gardens of Qing Dynasty, but also lay an important foundation for the ecological restoration and cultural landscape construction in this area.

Therefore, six research papers from SATU are featured in this issue, which are developed from various dimensions such as history, landscape, environment, transportation, city, community and governance based on the authors' observations and reflections during their years as responsible planners of streets and communities along the Qinghe River. It consists of two parts.The first part is about epistemology. Zhong, et al. summarises the geographical and historical evolution of Qinghe River area, and explores the relationship between the water and the urban development; Huang, et al. sorts out the functional evolutions of urban areas along the Qinghe River and proposes a development strategy integrating the Qinghe River with several important surrounding areas; Chen, et al. summarises the main problems and their causes faced by the development of waterfront spaces in the urban fringe of megacities, and puts forward the suggestions of waterfront space renewal to drive the development of urban fringes.

The second part is about practice. Wang, et al. concludes the space elements of comprehensive waterfront space management,and proposes improvement elements and management strategies combined with the characteristics of current waterfront spaces and structural features of the communities; Chen, et al. studies the use patterns and user needs of greenways through questionnaire surveys, and proposes several solutions to enrich the functions of the greenways; Liang, et al. proposes the relevant strategies to improve the traffic accessibility of waterfront space from road layout, pedestrian-oriented traffic, parking, and so on.The research demonstrated in this issue is still on-going work, which aims to provide multi-perspective interpretations for the renewal and improvement of the Qinghe River, and a reference for the urban design as well as refined management of waterfront spaces in the urban-rural areas of megacities in China.

About three years ago, when the team from Tsinghua University became the responsible planners, the plan of the landscape corridor of the Qinghe River was promoted to explore the approaches and methods of participatory planning to improve its environmental quality. Combined with its ecological landscape resources, and facing the needs of community with human-centred principles, blending landscape into the city and bringing life into the landscape is a good vision that has been partly realised in this area.

Our appreciation to Haidian Branch of Beijing Municipal Commission of Planning and Natural Resources, China Academy of Urban Planning and Design and many others, whose generous support makes this issue happened.□(Translated by PANG Lingbo)