黃劍
1 軍莊生態(tài)小鎮(zhèn)區(qū)位關(guān)系Junzhuang Eco-town location
從北京市區(qū)向西60km左右,就來到了京郊傳統(tǒng)度假地之一的軍莊鎮(zhèn)(圖1)。根據(jù)《北京城市總體規(guī)劃2016——2035》中提出的“一核一主一副,兩軸多點一區(qū)”的城市空間結(jié)構(gòu),其中“一區(qū)”是指包含門頭溝在內(nèi)的淺山生態(tài)涵養(yǎng)區(qū),是首都重要的生態(tài)屏障和水源保護地,也是保障首都可持續(xù)發(fā)展的關(guān)鍵區(qū)域,承載著接受平原發(fā)展輻射和帶動山區(qū)城鎮(zhèn)化的雙重職能。北京淺山區(qū)指高程在100~300m之間的淺山丘陵地區(qū),其中軍莊鎮(zhèn)緊鄰永定河,三面環(huán)山,在北京水系生態(tài)走廊和淺山生態(tài)屏障上占據(jù)了重要的地位,并且是區(qū)域生態(tài)廊道上的一塊“踏腳石”(steppingstone)。旅游和經(jīng)濟發(fā)展的壓力與脆弱生態(tài)環(huán)境的保育,是軍莊鎮(zhèn)面臨的突出課題。
通過生態(tài)、經(jīng)濟和社會要素的平衡互動來實現(xiàn)可持續(xù)的社區(qū)發(fā)展是設(shè)計的重要策略 (圖2)。我們將淺山區(qū)視為一個生命系統(tǒng),通過構(gòu)建區(qū)域生態(tài)基礎(chǔ)設(shè)施來引導(dǎo)和約束城區(qū)發(fā)展,構(gòu)建安全的淺山生態(tài)格局,強調(diào)對生態(tài)環(huán)境和自然空間的保護,并且從設(shè)計上加強林相修復(fù)和生物棲息地的復(fù)建,逐步提升生物多樣性,使這個生命系統(tǒng)更健康,更具韌性。
人與自然的長期互相塑造,成就了軍莊小鎮(zhèn)的特色風(fēng)貌,也造成了水土流失、植被群落單一和生物品種不斷減少的脆弱生態(tài)環(huán)境(圖3)。設(shè)計團隊在對160hm2的軍莊文旅休閑特色小鎮(zhèn)進行景觀規(guī)劃設(shè)計的同時,也同步展開針對全鎮(zhèn)3 000多hm2的生態(tài)環(huán)境的綜合評估和保護規(guī)劃,在“生態(tài)優(yōu)先”的理念下因地制宜地制定了林地修復(fù)、棲息地重建、水資源與水生態(tài)綜合管理等6個生態(tài)環(huán)境修復(fù)策略和20個具體措施。其中,水資源管理,林地和棲息地復(fù)育是可持續(xù)環(huán)境保育的核心策略。
水資源管理方面,設(shè)計團隊著重通過蓄滯、凈濾和節(jié)水3個層面,對水資源進行合理規(guī)劃和管理,構(gòu)建軍莊小鎮(zhèn)的海綿系統(tǒng)(圖4,表1)。為了保證轄域內(nèi)防洪安全,項目組一方面建議河道修復(fù)、疏挖溝渠等措施,并根據(jù)水流勘測的數(shù)據(jù)進行各類排洪渠的合理布置,以達到快速排洪的效果;另一方面,在水量和流速較小的上游地區(qū)則設(shè)計緩坡、石籠等更為友好的生態(tài)駁岸,改善自然親水的山地水環(huán)境。在規(guī)劃的小鎮(zhèn)中心區(qū)域,場地順應(yīng)地勢分成5個標(biāo)高區(qū)域,通過巧妙設(shè)置季節(jié)性的水景、生態(tài)草溝、雨水花園和干塘,既保留了原有沖溝的場地記憶,又實現(xiàn)了場地地表徑流的有效收集與回用。
此外,根據(jù)地形的塑造和徑流關(guān)系的分析在全區(qū)布置的干塘、雨水花園和生態(tài)草溝等,就像一個個海綿細(xì)胞,能夠蓄滯和凈化地表徑流,滋養(yǎng)土壤和植被,回補地下水,也緩解了市政排水及排洪的壓力,更好地實現(xiàn)水凈化和水安全。
淺山區(qū)的地貌十分復(fù)雜,而且普遍面臨退化、侵蝕、污染等問題。在對鎮(zhèn)域的生態(tài)分析中,設(shè)計團隊以國土林地斑塊為基礎(chǔ)(主要為林場保護區(qū)邊界及鎮(zhèn)村落邊界),在GIS技術(shù)支持下以根據(jù)林地修復(fù)條件相關(guān)的因子,主要包括海拔高度、地形坡度、土層深度、現(xiàn)有林地條件以及景觀可視性等,將鎮(zhèn)域內(nèi)的主要林地劃分為五大林地修復(fù)類型:退化林地修復(fù)、城鎮(zhèn)景觀林營造、陡坡地和容易被侵蝕的地區(qū)林地修復(fù)、廢棄礦山周邊綠化、林地棲息地修復(fù)(圖5)。
整個鎮(zhèn)域現(xiàn)狀林業(yè)用地面積為1 889.35hm2,其中可實施修復(fù)林地的面積為2 150.89hm2。規(guī)劃考慮10年的中長期林地修復(fù)計劃,逐步形成約64.5%以上的淺山特色林地區(qū)域。針對目前淺山區(qū)以次生林為主的樹種單一、群落結(jié)構(gòu)簡單等問題,采用局部疏伐、逐步更新等方式,以形成生物多樣性更豐富的混交林(圖6)。
退化的林相問題也帶來過去百年間淺山地區(qū)物種數(shù)量的大幅下降。為此,景觀設(shè)計師與生態(tài)專家緊密協(xié)作,根據(jù)當(dāng)?shù)靥厣珓游镔Y源設(shè)立目標(biāo)先鋒種群,配置合理的植物群落以提供多樣化的筑巢、繁衍環(huán)境,吸引區(qū)域小型哺乳動物、林鳥、昆蟲等,重建生態(tài)友好的淺山特色棲息地(圖7)。根據(jù)陡坡、平地等不同場地類型和坡向關(guān)系,設(shè)計團隊制定了土壤、植被與生物的同步分級恢復(fù)策略,布置適宜的鄉(xiāng)土樹種和先鋒物種,通過長期的生態(tài)保育計劃促進自然的正向演替,逐步修復(fù)退化的林地,提高土地的生態(tài)服務(wù)功能,并形成多樣化的混交林。
2 可持續(xù)社會發(fā)展示意圖Social sustainable development diagram
3 區(qū)域生態(tài)適宜性分析Analysis of regional ecological suitability
4 區(qū)域干塘調(diào)蓄設(shè)施規(guī)劃及分區(qū)圖Planning and zoning of regional dry pond storage facilities
表1 區(qū)域干塘調(diào)蓄設(shè)施規(guī)劃及分區(qū)表Tab. 1 Regional dry pond planning and chart
山地景觀設(shè)計對現(xiàn)狀和自然要素高度敏感,十分需要因地制宜,巧于因借。設(shè)計團隊秉持“生態(tài)優(yōu)先,修復(fù)基于保護”的理念,通過對資源的重組和空間的重構(gòu),增加豐富的策劃內(nèi)容,讓小鎮(zhèn)更優(yōu)美、更生態(tài)(圖8)。
結(jié)合分區(qū)策劃和生態(tài)環(huán)境規(guī)劃策略,設(shè)計團隊在小鎮(zhèn)農(nóng)場附近設(shè)置了一片以“大自然的秘密”為主題的親子互動區(qū)域,配合專業(yè)的自然教育課程讓人們在休閑玩樂的過程中接觸、感知和探索大自然,親身感受人與樹木、鳥類、昆蟲等自然環(huán)境親密共生的關(guān)系。自然生境的重塑不僅是單純的景觀修復(fù),更是鮮活可見的生態(tài)教育過程。
軍莊鎮(zhèn)是京西古道上的節(jié)點,歷史人文景觀和旅游資源十分豐富。北京特產(chǎn)京白梨就產(chǎn)自軍莊鎮(zhèn),這里有從清代延續(xù)至今具有400年歷史的貢梨園。春天開遍山野的潔白梨花,夏秋之交甘甜綿軟的京白梨,不僅是老北京的美好記憶,更是當(dāng)?shù)厝说尿湴梁蜕嬷尽?/p>
設(shè)計中保留了所有的果園,并提出了土壤的生態(tài)優(yōu)化措施,停用化肥,改傳統(tǒng)的井水灌溉為滴灌、噴灌結(jié)合。建議原本的單一梨樹種植改為四季套種、種植——養(yǎng)殖結(jié)合等復(fù)合式種植。這不僅能夠顯著節(jié)水,還能改良土壤,提高土地生產(chǎn)效率,改善微氣候并促進自然資源的良性循環(huán)和動態(tài)平衡,也讓梨園呈現(xiàn)出更豐富的季節(jié)性景觀 (圖9)。
基于綜合環(huán)境敏感度評估確定適宜的開發(fā)強度和場地的可承載力,利用本土資源和農(nóng)業(yè)相關(guān)知識,建立生態(tài)、農(nóng)業(yè)和旅游相結(jié)合的系統(tǒng),推行“樸門農(nóng)業(yè)”和“綠色旅游Green Globe”可持續(xù)旅游標(biāo)準(zhǔn),以保護環(huán)境、維護生態(tài)平衡為前提,鼓勵社區(qū)參與和體驗式的旅游。
“隴駕莊,會編筐,男的打底,女的上邦”,一句當(dāng)?shù)亓鱾鞯拿裰V,道出了京西荊編的好口碑。京西山區(qū)盛產(chǎn)荊條,荊編就地取材,可以編出背簍、籮筐,也可以搭棚、鋪頂,而且能夠變換出豐富的紋理效果。這本是家家戶戶流傳的手工藝,不過隨著現(xiàn)代化生活的普及,荊編也在逐漸退出村民的生活舞臺,直到與我們的景觀設(shè)計團隊相遇。荊編被定義為一種重要的景觀元素在場地內(nèi)廣泛應(yīng)用,比如梨園的圍欄、籬笆,甚至入口的墻面、小鎮(zhèn)客廳的涼亭,并且通過這個元素的發(fā)掘,大力鼓勵村民的廣泛參與和創(chuàng)造性的發(fā)揮,最終讓荊編工藝的展現(xiàn)和應(yīng)用成為項目中一個精彩的亮點,也讓村民從中體會到手工藝帶來的自豪(圖10~12)。
5 林地修復(fù)過程示意Forestry restoration process
6 區(qū)域林地修復(fù)類型Regional forestry restoration zoning plan
7 林地棲息地復(fù)建示意圖Forest habitat restoration diagram
9季相綜合管理示意圖Quarterly integrated management diagram
原本主要是生產(chǎn)性質(zhì)的貢梨園在入口區(qū)改造后呈現(xiàn)出現(xiàn)代和開放的面貌。入口旁邊的保留建筑被改成小鎮(zhèn)客廳及生態(tài)展示中心。室外的空場地上,我們結(jié)合休息區(qū)域增加了可供休息和停留的綠島形成對景,并作為場地海綿設(shè)施的一部分。原有的場地邊界通過傳統(tǒng)工藝和材料,在原址上用毛石手工砌筑成傳統(tǒng)的城墻樣式,保留著這里的場地記憶,傍晚在這里遠(yuǎn)眺夕陽可以欣賞西山優(yōu)美的天際線。場地周邊的梨樹和其他大樹全部被保留,在展示中心外面的小徑還特意下挖了1m多以避讓現(xiàn)場的老樹。層層的梨園臺地之間增加了雨水花園,臺地間設(shè)置休息平臺,上面的休息涼亭是村民和設(shè)計師共同創(chuàng)作的荊編作品。所有的材料和工藝都來自當(dāng)?shù)?,梨園的傳統(tǒng)生產(chǎn)過程通過銅浮雕墻展現(xiàn)。建成后這里不僅成為小鎮(zhèn)的生態(tài)展示中心,更是屬于村民的小鎮(zhèn)客廳(圖13~15)。
通過景觀、生態(tài)、林業(yè)、水利、巖土,旅游及經(jīng)濟策劃等多專業(yè)的跨界合作,設(shè)計團隊從多元角度的分析發(fā)現(xiàn)議題,制定適合軍莊的規(guī)劃設(shè)計策略,并且一直深入到工程執(zhí)行層面,保障現(xiàn)場的施工成效。軍莊生態(tài)小鎮(zhèn)的規(guī)劃設(shè)計還未結(jié)束,作為北京淺山區(qū)生態(tài)保護與開發(fā)的一次嘗試,希望探索出一條“修復(fù)基于保護的生態(tài)規(guī)劃,策劃結(jié)合現(xiàn)狀的景觀設(shè)計”的淺山區(qū)特色小鎮(zhèn)的可持續(xù)之路。
(編輯/王一蘭)
項目地址:北京門頭溝軍莊鎮(zhèn)
生態(tài)規(guī)劃和景觀設(shè)計公司:AECOM
設(shè)計團隊:沈同生,David Gallacher,黃劍,羅志堅,王福龍,趙星,李露曦,李琦,鮑艾艾,陸瑤,楊寧婧,江丹
項目時間:2017年
項目面積:160hm2
圖片來源:AECOM
8 場地景觀剖面Landscape long section
10 民間工藝荊編的設(shè)計與應(yīng)用Design and application of folk craftsmanship vitex weaving
60 kilometres from Beijing, Junzhuang Town is a traditional tourist destination due to its natural beauty and pear orchard. In the Beijing Masterplan it is defined as part of the low mountain ecoconservation area, which is not only an ecological buffer of Beijing, but a radial influence on the developed plain area. Highly sensitive, valuable and fragile, Junzhuang is an important stepping stone in the Beijing eco-corridor.
Hillside areas are a living system. We are looking to a sustainable social development of hillside area based on ecological restoration, local engagement and integrated design. Our ecological planning provides guidelines to limit urban development, build safe landscapes, and nurture the protection of natural public spaces and still grow economically. By strengthening the forest and habitat restoration through design, biodiversity can be improved and the eco-system can be more healthy and resilient.
11 當(dāng)?shù)鼐用駞⑴c建造荊編涼亭Local residents engaged in the construction of vitex woven pavilion.
12 荊編涼亭建成實景Photo of vitex woven pavilion
13 貢梨園入口序列長剖面Long section of entrance sequence of Royal Pear Orchard
14 貢梨園入口實景Build photo of Royal Pear Orchard entrance
On the site, the gate of the orchard is renovated to be a friendly exhibition center, and a “l(fā)iving room”for local community. Surrounded by preserved pear trees, a modern and sculptural chaste-weaving pavilion is created by the collaborative effort of landscape designers and local villagers, linking the new landscape with the local traditional craftsmanship. A copper embossed screen wall describes the traditional pear producing process. Through the landscape, culture,ecology and economy can be integrated smoothly.
For flood control, varies methods of river restoration, dredging and ditching are suggested.Drainage channels, dry ponds, rain gardens, and bio-swales are arranged based on water flow survey data and terrain and runoff analysis. Eco-friendly embankment methods e.g. gentle slope and gabion wall are used in the upstream areas where flow rate are low.
Following the original contours and a natural gulch on site, the layout of town center is integrated with storm water management design.Seasonal water features are designed with dry ponds and rain gardens, bringing the memory of site into its modern life.
The design team developed a hierarchically recovery strategy in which soil, vegetation and biological will be improved simultaneously for varies terrain types and slopes. The design can promote positive forest succession by making longterm ecological conservation plan and planting appropriate native tree species and pioneer species.Through natural restoration of degraded forest land, the site’s ecological service function will be improved gradually, and eventually forms diverse mixed forests.
Set up target pioneer species and communities based on native biological resources. Create diversified nesting and breeding environments which shall attract regional small mammals, forest birds, insects and etc. by planting appropriate vegetation communities, and ecologically friendly low mountain habitats will be restored.
Beijing White Pear is a special local product from Junzhuang Town, especially the ones from “Royal Pear Orchard” with over 400 years history. All pear orchards are well protected in the planning. Permaculture measurements are proposed - previous underground-water irrigation and chemical fertilizer are replaced by dripping irrigation and community participated bio-farming,more energy saving and productive.
It is suggested that the original single pear tree planting to be changed to composite planting model in four seasons, conserving more and improve soil quality, land production efficiency, and microclimate.
Not only more effective agriculture production and management, but also better interactive green tourism programs are proposed, such as nature school and camping, bird watching, eco-sightseeing and organic farming. All programs are based on the local natural resources, and involved with local communities, to reduce the disturbance of the site,and improve the long time economic benefit to the communities.
“Good baskets from folks in Longjia Village,man works on the frame and woman on the detail.”
The folk song tells the long history and reputation of chastetree weaving in this area.Western Beijing mountainous area abounds in chastetree, so the villagers uses the local material to make plates, baskets, fences, and roof tops.This is a simple technology with countless rich patterns created by villagers’ imagination and interest. Chastetree weaving was a popular handicraft for every household, but in modern life, it has gradually fading out from the everyday life of the villagers until it meets our landscape design team.
The construction started from the entry area of the Royal Pear Orchard which has over 400 year’s history. The entrance of the Royal Pear Orchard is an important connection of public open space with production area, and is a place for people to meet and talk. A few steps up along the main axis of Royal Pear Orchard through the renovated modern gate, guest will meet with a copper embossed screen wall telling the story of traditional pear production process. The design follows the topography and retains existing trees and the rough walls which outlined the site. The existing building is transformed into an eco-display center. A green island is added on the plaza to provide rest area, also form the view and helps“sponge” function of the site. The original rough stone wall and the pear trees remains on site, to keep the memory of the place. From the platform looking west on the sunset, the silhouette of west mountain is stunning.
15 小鎮(zhèn)客廳建成實景Photo of town living room
Pass through the exhibition center towards the terrace garden, a path is dropped 1 meter to bow to the existing big, old verdant tree, as a salute to the history. A few rain gardens are created among terraces to guide the water flow. A modern and sculptural chaste weaving pavilion on the terrace garden becomes the focal point; this is a creative art by the collaboration of villagers and landscape designers, using traditional local material and technique, linking the new landscape with the local traditional craftsmanship.
The entry area then becomes not only a welcoming and exhibition center, but also the favorite gathering place that local villagers are proud of, a place where people join and see the contrast of before and after, experiencing the new lifestyle in an old village. It transforms an old culture into a new one, and then becomes a modern vision of an eco-village celebrating its unique tradition.
The cross line corporation from landscape,environment, forestry, water utility, geotechnical engineer, tourism and economic planning brings a multi-benefit perspectives. The strategy of long term social sustainable development implements from planning to construction. This is still an ongoing process and experiment for “eco-planning of renovation based on protection, landscape design integrated with programming” for hillside area.
Location: Mentougou Junzhuang Town, Beijing
Design Firm: AECOM
Design Team: Stone Shen, David Gallacher, Jane Huang,Oliver Luo, Fulong Wang, Smile Zhao,Heather Li, Lizzie Li, Aiai Bao, Yao Lu,Ningjing Yang, Lotus Jiang
Construction: 2017
Site Area: 160hm2
Photo and Image: AECOM