英國謝菲爾德大學(xué)詹姆斯·希契莫夫教授對話北京林業(yè)大學(xué)董麗教授

采訪：尹豪 同聲翻譯：杭燁

左：董麗；右：詹姆斯·希契莫夫Left: DONG Li; Right: James Hitchmough

訪談人物：

（英）詹姆斯·希契莫夫/英國謝菲爾德大學(xué)景觀學(xué)院院長、生態(tài)園藝學(xué)教授/研究方向?yàn)榇笠?guī)模草本及木本植物群落自然式種植設(shè)計(jì)與管理

董麗/北京林業(yè)大學(xué)園林學(xué)院副院長、教授/研究方向?yàn)閳@林植物景觀規(guī)劃設(shè)計(jì)、園林生態(tài)等相關(guān)理論研究、實(shí)踐及教學(xué)/本刊編委

Profiles：

James Hitchmough who is from Britain is the dean in School of Landscape and professor of ecological horticulture the University of Sheffield. His research focuses on design and management of natural planting of herbaceous and woody vegetation.

DONG Li is the assistant dean, professor of School of Landscape Architecture,Beijing Forestry University and editoral board member of this Journal. Her research focuses on theory, practice and teaching relating to plant landscape planning and design and Landscape ecology.

詹姆斯·希契莫夫教授提出了具有生態(tài)概念的投入可持續(xù)植物群落設(shè)計(jì)的理論，成功完成了2012倫敦奧林匹克公園中20hm2的種植設(shè)計(jì)，整個(gè)設(shè)計(jì)是基于生態(tài)學(xué)原理的草本植物群落種植設(shè)計(jì)，并形成了全新的“生態(tài)皮膚”這一理念。董麗教授引入“自然度”和“近自然園林”的概念，在研究地帶性植被特征的基礎(chǔ)上，成功主持完成了北京奧林匹克森林公園的植物景觀生態(tài)規(guī)劃，營造出一個(gè)能體現(xiàn)地帶性植物基本特點(diǎn)，并具備良好的生態(tài)功能的森林公園植物景觀。

本刊特約編輯尹豪副教授主持了詹姆斯·希契莫夫教授與董麗教授的訪談對話，通過2位教授的思想交流與碰撞，我們了解到當(dāng)下城市建設(shè)中生態(tài)種植設(shè)計(jì)有待解決的一些研究點(diǎn)或研究方向。啟示我們，在以后的科研、教學(xué)或?qū)嵺`中，找準(zhǔn)自己的研究點(diǎn)，切實(shí)地為解決城市環(huán)境下的生態(tài)種植設(shè)計(jì)提供有效的理論指導(dǎo)和技術(shù)支撐。

LA：《風(fēng)景園林》

James： 詹姆斯·希契莫夫

DONG： 董麗

LA：James 教授您的設(shè)計(jì)是很自然的設(shè)計(jì)風(fēng)格。外行人看來，在某種程度上好像沒有設(shè)計(jì)。您能否與我們分享一下這種種植設(shè)計(jì)方法的內(nèi)在邏輯？推行這種方法您需要跨越什么障礙？

James：自然式生態(tài)種植設(shè)計(jì)，雖然看起來好像是接近于自然，似乎是沒有設(shè)計(jì)過的，但是好的自然式設(shè)計(jì)就是設(shè)計(jì)得沒有痕跡。我的設(shè)計(jì)靈感來源于自然，以植物個(gè)體或組團(tuán)在群落中重復(fù)出現(xiàn)為表現(xiàn)形式，我試圖用大家所期望看到的色彩、結(jié)構(gòu)和變換，來創(chuàng)造物種豐富、具有圖案感與韻律，隨著季節(jié)變換，能在很長的觀賞季中呈現(xiàn)戲劇化變幻特征的植物景觀。雖然這跟中國當(dāng)前普遍的規(guī)則式種植有很大的不同，也顯得野趣，但看著更為自然。正是這種在沒有人為干擾下，戲劇化的自然演替吸引著越來越多的人，這種種植形式因此逐漸被大眾所接受（圖1）。

我非?？粗厥缊@會(huì)的這次機(jī)會(huì)，因?yàn)檫@個(gè)平臺(tái)給了我一種可能性，讓我來創(chuàng)造這種形式，然后來驗(yàn)證這種形式在中國的接受度。記得在6個(gè)月之前，我在國際學(xué)術(shù)期刊《城市林業(yè)與城市綠化》上，第一次看到來自中國的作者關(guān)注這類擬自然式生態(tài)種植形式是否能給北京大眾帶來不同的審美需求和感受。在仔細(xì)地閱讀了這篇文章以后，我發(fā)現(xiàn)中國的民眾對這種新型種植方式的反應(yīng)，實(shí)際上跟西方的審美理念有高度的統(tǒng)一和吻合。因此我覺得，中西方在審美標(biāo)準(zhǔn)和生態(tài)需求方面或許并沒有很大的差別。

LA：董教授，說到自然，其實(shí)中國傳統(tǒng)就很自然，對于自然的理念，您認(rèn)為它和英國的自然有著什么樣的差別？您的見解是什么？是否可以給我們分享一些。

DONG：說到自然，這是一個(gè)很大的話題。如Hitchmough 教授所言，我覺得我們可以理解為，其中一種自然即“大自然的自然”，即天然的自然，比如園林中營造的meadow這種景觀的形式，其實(shí)就是從大自然中借鑒和學(xué)習(xí)過來的，所以他希望他的設(shè)計(jì)沒有痕跡，就像和自然是一樣的；另一種自然，則可說是“人造的自然”，換而言之，是人類通過對大自然進(jìn)行借鑒和提煉，在人工環(huán)境中重新建成的“自然”，它雖然并不是真的照搬原生的自然，但也確實(shí)遵循“雖由人作，宛自天開”的理念，這就是我們中國傳統(tǒng)園林的“自然”，即非真正的大自然，卻是學(xué)習(xí)自大自然的產(chǎn)物。所以我們中國傳統(tǒng)就有“師法自然”，這種理念一直是中國傳統(tǒng)造園的一個(gè)核心宗旨。但是在過去的幾十年，我國在植物景觀營造過程中走過一些彎路，過度強(qiáng)調(diào)人的視覺美，使得我們的城市環(huán)境失去了太多的自然的氣息。我想這可能就是剛才Hitchmough教授所說的我們中國的種植設(shè)計(jì)都是規(guī)則式設(shè)計(jì)的緣故吧。不過，慶幸的是，如今我們正逐漸回歸到正確的方向上來。所以我認(rèn)為對這種自然設(shè)計(jì)理念和手法的再次探索，及其在城鄉(xiāng)植物景觀規(guī)劃設(shè)計(jì)中的應(yīng)用實(shí)踐，是非常有意義的事情。

1 倫敦奧林匹克公園中人們對詹姆斯·希契莫夫設(shè)計(jì)的南非花園的高度認(rèn)可People’s positive respond to the South African herbaceous planting community designed by James Hitchmough in London Olympic Park

2 自然式園藝景觀私家花園打造“綠色生活”，詹姆斯·希契莫夫設(shè)計(jì)Enhanced nature-like private garden in August, designed by James Hitchmough

LA：因?yàn)?019世園會(huì)，我們相聚，本屆主題“綠色生活，美麗家園”，請問2位教授如何理解這一主題。

James：在我看來，這個(gè)主題非常好、非常棒，也非常契合現(xiàn)代發(fā)展的趨勢，對于我來說，可以以另外一種方式來理解這個(gè)主題，也就是園藝和生態(tài)的關(guān)系。如何將兩者更好地交融，更好地重新去詮釋它，做有生態(tài)意義、生態(tài)概念的園藝，并不失其園藝特征。在大多數(shù)的城市景觀實(shí)踐中，我們需要平衡生態(tài)和園藝的比重，力爭創(chuàng)造取悅大眾的景觀環(huán)境（圖2）。正如我們幾分鐘前談到的規(guī)則式和自然式景觀，的確，我們有時(shí)需要非常規(guī)則整齊的種植，但我們也可以嘗試將更為自由的種植形式與規(guī)則式相結(jié)合。在某種程度上，我們期望借助世園會(huì)的這個(gè)展示平臺(tái)，展示不那么傳統(tǒng)的新的園藝趨勢。

同時(shí)我也認(rèn)為，如果我們希望生活環(huán)境變得更加美好，要有創(chuàng)新精神，也就是在我們的園藝?yán)?，我們要突破、要有新的途徑，而新的途徑是需要呈現(xiàn)給大家，讓我們的游客、民眾能夠看見，我認(rèn)為這個(gè)世園會(huì)將會(huì)是一個(gè)很好且很重要的平臺(tái)，讓設(shè)計(jì)師有機(jī)會(huì)能夠帶入一些新的理念，一些在西方和在我們的實(shí)踐應(yīng)用當(dāng)中已經(jīng)測試過的好的方式。也許，這些經(jīng)驗(yàn)?zāi)軌蚪o中國的決策層、專業(yè)人士帶來新的啟發(fā)，并有助于逐漸改變?nèi)藗儗Τ鞘芯坝^環(huán)境的看法和態(tài)度。

LA：董教授，這屆世園會(huì)主題是“綠色生活，美好家園”，或許由于我們漢字的詞隱含的意義會(huì)更多、更廣泛、更豐富，對于我們這次園藝大會(huì)的主題，您是不是有著更多的理解？

DONG：我覺得此次園藝大會(huì)“綠色家園，美好生活”的主題，提得非常好。正如你所說，中文每個(gè)字、每個(gè)詞背后的含義非常廣泛，因?yàn)槭菆@藝大會(huì)，當(dāng)我們看到“綠色”時(shí)，可能首先會(huì)想到作為顏色本身的綠色， 對于我們植物景觀營造等行業(yè)的從業(yè)者來說，則會(huì)很自然地引申為，“綠色”就是以植物為主導(dǎo)，讓我們生活、工作的環(huán)境更為美好。但其實(shí)“綠色生活”不僅僅限于上述的狹義“綠色”概念，其更加寬廣的含義首先應(yīng)該是體現(xiàn)一種理念，這種理念促使我們對人與自然關(guān)系進(jìn)行重新認(rèn)識(shí)，體現(xiàn)在人類必須熱愛自然、尊重自然、保護(hù)自然，才能最終與自然和諧發(fā)展。實(shí)踐中，則不僅要讓自然融入我們的生活環(huán)境、生產(chǎn)空間里面，更要注重我們生產(chǎn)生活方式的轉(zhuǎn)變，包括對自然資源的節(jié)約，環(huán)境友好的生產(chǎn)方式等等。所以這個(gè)“綠色生活”的理念和實(shí)踐應(yīng)該融入到我們生活、生產(chǎn)的方方面面，才能稱得上是“美好生活”。

LA：James教授，英國的花展很多，切爾西花展享譽(yù)世界，英國花展對民眾的吸引力主要體現(xiàn)在哪些方面？對改變民眾生活的影響有多大？

James：在我看來這是一個(gè)非常有趣的問題。我想，首先要說的是中國和英國社會(huì)文化的基礎(chǔ)不同，因?yàn)樵谟總€(gè)人幾乎都有自己的私家花園，所以可以說，英國的民眾和花展的潛在關(guān)系更為密切。而在中國，也許這一點(diǎn)是最大的差別。當(dāng)我們講到切爾西花展對于社會(huì)效應(yīng)方面的影響，我想應(yīng)該先從它的功能效應(yīng)來提及。首先作為一個(gè)花展，它主要是一個(gè)展示園藝多樣性的平臺(tái)，是一個(gè)供應(yīng)商與買家面對面接觸和交流的機(jī)會(huì)。切爾西花展更多的是展示英國作為園藝大國，在園藝上堅(jiān)持不斷地推陳出新，將新的好的產(chǎn)品源源不斷地推向市場。切爾西花展的游客們其實(shí)就是自己花園的設(shè)計(jì)師，他／她們看見心儀的花卉就可以買回家，或在商家的網(wǎng)站上購買，并種植在他們的私家花園里。今天的英國，你可以足不出戶地在自家的電腦上購買大約80 000種不同的植物品種及其園藝變種。英國的苗圃會(huì)根據(jù)市場需求，不斷地挖掘有景觀價(jià)值的新的野外品種，研發(fā)抗性強(qiáng)、觀賞性強(qiáng)的園藝品種。然后這個(gè)市場的鏈條就形成了，作為切爾西花展來說，它是一個(gè)平臺(tái)，是一個(gè)聯(lián)系每一個(gè)花園、每一個(gè)在英國愛好園藝的個(gè)體和產(chǎn)業(yè)鏈的紐帶，所以我認(rèn)為在中國，2019北京世園會(huì)，也會(huì)有類似的這種社會(huì)效應(yīng)，只是中國可能剛剛開始，在未來的話，我相信北京世園會(huì)也會(huì)像切爾西花展一樣，發(fā)揮它強(qiáng)大的社會(huì)效應(yīng)，它的功能性也會(huì)在中國逐漸體現(xiàn)。

因?yàn)樵谥袊?，百姓大多?shù)沒有私家花園，所以我認(rèn)為更多的關(guān)注應(yīng)該是中國的公共空間，思考這些公共綠地是否能承載人與園藝親密接觸的社會(huì)功能。比如在大面積單一樹種種植或林地景觀下層及林緣，應(yīng)該有更為豐富的種植；在居住區(qū)環(huán)境設(shè)計(jì)中，應(yīng)該有更為多樣的品種和豐富的種植結(jié)構(gòu)。北京需要更多季相變化、更多色彩、更多種植形式、更豐富的種植結(jié)構(gòu)，需要最大化地發(fā)揮城市公共空間的多功能性。

LA：其實(shí)說到園林園藝展，中國這幾年來也在不斷地舉辦很多的園林園藝展，也在切實(shí)地改變著我們的生活，也在推進(jìn)著社會(huì)的發(fā)展，董教授，您認(rèn)為就中國的園林園藝展的發(fā)展，從目前來看，我們還需要如何更好地服務(wù)于大眾？或更好地改變民眾的生活？

DONG：其實(shí)中國有著非常悠久的園藝歷史，但可能現(xiàn)代語境下的園藝展，我們不如英國那么強(qiáng)，像切爾西花展那么長歷史的園藝展我們確實(shí)沒有，然而改革開放之后這些年來，國內(nèi)園林園藝展之多是有目共睹的，盡管展覽過程中也曾出現(xiàn)過各種各樣的問題，但是我們很高興地看到這些問題在改變。實(shí)際上，這些園林園藝展迄今為止已經(jīng)對我們產(chǎn)業(yè)、行業(yè)的發(fā)展以及民眾對園藝的認(rèn)識(shí)都起到了很大的促進(jìn)作用。此次世園會(huì)的園藝展因其級別較高，首先政府層面就給予了高度重視。而借助這次展覽將廣泛展現(xiàn)世界上園藝發(fā)達(dá)國家和地區(qū)的園藝成果，這意味著此次園藝展必定會(huì)給我們帶來從理念、技術(shù)及產(chǎn)品的全方位的影響；另一方面，此次園藝展的成果，不僅限于建立了一個(gè)大展園，布置了很多今后能給我們帶來直接影響的實(shí)用性成果，也包括依托于這次展覽組織機(jī)構(gòu)在社會(huì)上舉辦的各類活動(dòng)，非常豐富，比如這次請大師們到學(xué)校來舉辦講座，還有今天的電視臺(tái)采訪，這些都對全社會(huì)在園藝、自然、生態(tài)環(huán)境等方面的認(rèn)識(shí)有重要的促進(jìn)作用。我相信未來這次世園會(huì)的成果不只會(huì)對政府、對公眾、對我們專業(yè)人員都將產(chǎn)生積極的影響，而且肯定會(huì)持續(xù)產(chǎn)生更多的成果。伴隨著這些成果的產(chǎn)生，園藝會(huì)讓民眾的生活環(huán)境、生產(chǎn)空間都越來越好。

3詹姆斯·希契莫夫?yàn)闇贰に箞D爾特-史密斯設(shè)計(jì)的北美的草花生態(tài)群落真正呈現(xiàn)了鳥語花香的景象North American herbaceous vegetation in Tom Stuart-Smith Garden attracts diverse of wildlife all year round,designed by James Hitchmough

LA：“鳥語花香”是一個(gè)描繪美好環(huán)境的詞，是人人向往的境地。近些年，北京加大了環(huán)境的治理工作，正在一步一步朝向這個(gè)美好愿望前行。請2位教授從專業(yè)角度給些建議，讓市民更多地聽到窗外的鳥鳴，嗅到飄入室內(nèi)的花香。

James：在“鳥語花香”里，我今天想先談?wù)劇傍B語”。作為“鳥語”來說，其實(shí)講的是生物多樣性的問題。北京的城市空間尺度非常巨大， 城市建設(shè)密度也很大，城市范圍內(nèi)僅有少數(shù)的空間能為個(gè)別鳥類提供棲息環(huán)境。在西歐國家的城市里，我們有很多私家花園，這些花園作為城市二級綠地，為野生動(dòng)物提供棲息環(huán)境。正因?yàn)槲鞣絿也煌耐恋匦再|(zhì)、尺度比例和擁有無數(shù)能支持昆蟲和鳥類的私家花園，我們才能在西方城市中看到比中國城市里豐富得多的鳥類品種。

其實(shí)，有很多條途徑可以改變中國城市生物多樣性不足的現(xiàn)狀。其中，最行之有效的方法之一是在城市范圍內(nèi)構(gòu)建更為復(fù)雜且豐富的種植結(jié)構(gòu)。實(shí)際上在不同的冠層層面上都可以變得更加復(fù)雜，地被層也可以有豐富的結(jié)構(gòu)。北京有非常大的植樹面積，但是這些樹絕大多數(shù)都相對來說比較年輕，且品種單一。如果北京的城市綠化能夠選用更為豐富的喬灌草品種，而且在空間層次上考慮更為豐富且多樣的結(jié)構(gòu)來營建，北京將能支持更多的生物。其次，從整體的城市規(guī)劃來看，在新的規(guī)劃理念上，西方認(rèn)為，把周圍的自然環(huán)境延伸滲透進(jìn)入城市空間，城市和自然環(huán)境共融發(fā)展是最理想的生態(tài)城市建設(shè)模型。也就是說在北京現(xiàn)有的城市環(huán)境里面，創(chuàng)建一些由城郊進(jìn)入城市的廊道空間；如果是新區(qū)規(guī)劃，盡量保留一部分現(xiàn)狀自然／半自然綠地。這些人為創(chuàng)建的和自然保護(hù)的綠色廊道空間將能夠幫助生物通行，支持生物棲息。生活在城市中的人們也就有了感受“鳥語花香”這種城市體驗(yàn)的機(jī)會(huì)（圖3）。

LA：說到“鳥語花香”，董教授，其實(shí)在前幾天剛剛結(jié)束的第3屆風(fēng)景園林植物與人居環(huán)境建設(shè)論壇上，您就在主旨報(bào)告上提起過這個(gè)美好的愿景，據(jù)我所知，這些年來您也在進(jìn)行積極的探索和研究，那么我們想聽取一下您在這些方面的一些深入的思考和專業(yè)化的成果研究。

DONG：的確，“鳥語花香”是我們每個(gè)人夢想的生活環(huán)境。其實(shí)我們?nèi)祟愒?jīng)就是生活在這樣的環(huán)境里，如今再提出這種夢想和愿景，或許就跟我們中間走了一段彎路有關(guān)，我們的確缺失了這樣的環(huán)境。正如Hitchmough教授所言，在北京和其他的中國大城市中，這樣的問題或許更加突出，因?yàn)槲覀兊某鞘忻娣e巨大，城市人口也更為密集，加上在之前的生態(tài)環(huán)境建設(shè)中存在的問題造成生物多樣性降低、鳥類棲息地不足，導(dǎo)致我們的城市缺乏“鳥語花香”的美麗環(huán)境。改變這種狀況，需要我們做什么？我們又能做什么？作為植物景觀規(guī)劃設(shè)計(jì)的從業(yè)者，我想說植物景觀可以規(guī)劃設(shè)計(jì)，鳥類卻無法規(guī)劃設(shè)計(jì)，我們能做的是去規(guī)劃設(shè)計(jì)良好的植物景觀，給鳥類和其他動(dòng)物提供良好的棲息環(huán)境，才能把它們吸引來并且留下來。所以提到生物多樣性，我覺得植物要先行，其中最關(guān)鍵的是植物的多樣性以及植物景觀的多樣性。植物的多樣性簡單地說就是種類上的多樣性，物種的豐富度，能夠提供鳥類所需求的食源、筑巢、繁殖等棲息環(huán)境。而植物景觀的多樣性同樣也非常重要，不同類型的植物配置結(jié)構(gòu)都是鳥類棲息地必不可少的要素，哪些鳥類需要復(fù)層混交的種植結(jié)構(gòu)，哪些鳥類需要灘涂濕地等，都需要植物景觀采取針對性的設(shè)計(jì)策略。當(dāng)然在這之上還有更為重要的層面，即綠地布局的合理性，包括廊道、斑塊等綠地類型及其合理的格局關(guān)系。這些方面都做到了，才能為吸引更多鳥類或營造生物多樣性更豐富的環(huán)境提供基礎(chǔ)。歸根結(jié)底，適宜的人居環(huán)境是要人與自然和諧共處。我們的目的不僅僅是要讓動(dòng)物都來，我們?nèi)祟愐采钤诔鞘协h(huán)境中，城市也理應(yīng)是人的最佳生存空間，所以人與自然共融才是我們追求的最終目標(biāo)。

LA：2位都是植物景觀規(guī)劃設(shè)計(jì)方面研究的專家，2位可否就這么多年來的科研、教學(xué)抑或是實(shí)踐項(xiàng)目，來談一談植物景觀規(guī)劃設(shè)計(jì)對于城市人居環(huán)境的改善？

James：我認(rèn)為種植設(shè)計(jì)的形式相對來說不那么重要，如何通過植物景觀規(guī)劃設(shè)計(jì)將不同的視覺和空間體驗(yàn)傳遞給大家，是更為有趣且有意義的方面。人們在城市環(huán)境中需要的是一種季節(jié)變化的感覺，而這一切是通過花開花落或者葉片的顏色變化等來實(shí)現(xiàn)的，這意味著人們期望身邊總會(huì)有一些有趣的和刺激感官的事情發(fā)生。其中的關(guān)鍵是如何找到合適的設(shè)計(jì)途徑，滿足人們在各個(gè)階段的審美需求（圖4、5）。

DONG：植物景觀對城市人居環(huán)境的改善是多方面的，市民們最能感同身受的比如綠樹紅花使我們的城市人居環(huán)境更為優(yōu)美，比如夏天去公園可以有一個(gè)陰涼舒適的休憩游覽的空間。當(dāng)然，植物也發(fā)揮著很多我們不一定能看到或者意識(shí)到的各種效益?？傮w上，除了美化環(huán)境，植物對城市人居環(huán)境的重要意義還體現(xiàn)在改善我們的生態(tài)效益上，如降溫、防護(hù)、凈化空氣、隔離噪聲、為其他動(dòng)物等提供棲息環(huán)境等，同時(shí)植物也具有重要的文化意義，是地域性文化傳承的載體，這種文化的意義對市民的作用可能是潛移默化的，但的確是存在的。

LA：在具體的實(shí)踐項(xiàng)目中，2位都曾做過大型城市公園的生態(tài)種植設(shè)計(jì)，James教授做過2012年倫敦奧林匹克公園的種植設(shè)計(jì)，董教授做過2008年北京奧林匹克森林公園的景觀生態(tài)規(guī)劃，2位可否分別談一談當(dāng)時(shí)實(shí)踐的一些基本生態(tài)學(xué)理論指導(dǎo)思想或者當(dāng)時(shí)遇到的瓶頸以及一些解決措施？

James：我長期致力于研究如何運(yùn)用生態(tài)學(xué)原理，構(gòu)建長期穩(wěn)定的植物群落，探索分析群落中不同植物間的相互競爭關(guān)系，以及這些種間競爭是如何影響群落穩(wěn)定性的。我們用來獲得最佳結(jié)果的杠桿常常是精心的植物選擇和合理的植物群落的設(shè)計(jì)，盡量減少優(yōu)勢物種對其相鄰物種的抑制作用（通常，我會(huì)通過在設(shè)計(jì)中降低這些優(yōu)勢物種的使用密度來減少影響）。其次，使用相對瘠薄的土壤來減緩物種的生長速率，以減少群落中的種間競爭。但是，有些客戶想要快速見到效果，這就產(chǎn)生了新的問題：如果追求快速見效，就無法在群落建立的初期有效控制種間競爭；如果要實(shí)現(xiàn)長期的群落穩(wěn)定性，就不能在建立初期快速產(chǎn)生效果（圖6、7）。

DONG：我是2005年受邀進(jìn)入北京奧林匹克森林公園總體規(guī)劃團(tuán)隊(duì)的，除了擔(dān)任團(tuán)隊(duì)專家成員外，具體承擔(dān)了奧森的植物景觀生態(tài)規(guī)劃的任務(wù)。應(yīng)該說一個(gè)700多hm2、如此巨大，且被稱為是“森林公園”的項(xiàng)目，當(dāng)時(shí)對我們是有挑戰(zhàn)的。經(jīng)過思考,我認(rèn)為既然叫“森林”公園，植物景觀營造應(yīng)該是這個(gè)公園最重要的內(nèi)容，而且植物景觀至少應(yīng)該滿足2點(diǎn)：一是外貌像森林。森林的特點(diǎn)是什么？像哪里的森林？如何做到像森林？首先森林的特點(diǎn)當(dāng)然是自然，其二當(dāng)然是像這個(gè)地帶的森林。其三如何做到像森林，我們引入近自然園林的設(shè)計(jì)理念，引入了“自然度”的概念，研究了北京地區(qū)不同“自然度”條件下植被的構(gòu)成特征，為森林公園植物景觀規(guī)劃設(shè)計(jì)奠定基礎(chǔ)。第二個(gè)大的方面是具備一點(diǎn)森林的功能。我們不敢說城市里人工建造這么一塊綠地要能發(fā)揮像真正的自然界的森林一樣的功能，但是我們至少要發(fā)揮部分的功能，而森林最重要的功能是什么？就是棲息地的功能。所以當(dāng)時(shí)2005年我們就從棲息需求的角度研究了北京地帶性的動(dòng)物對于植物的需求，當(dāng)然是一個(gè)很初步的研究，以此作為我們選擇植物的依據(jù)之一。當(dāng)然還要考慮很多其他方面，包括適應(yīng)性、生態(tài)效益及文化性等等。應(yīng)該說，當(dāng)初的這些研究都沒有白做，如今森林公園的確在動(dòng)物，尤其是鳥類棲息地方面發(fā)揮了巨大的作用，目前已經(jīng)發(fā)現(xiàn)了200多種鳥類在此活動(dòng)（圖8～15）。

4 倫敦奧林匹克公園坡面草花群落設(shè)計(jì)，詹姆斯·希契莫夫設(shè)計(jì)Designed vegetation on slope in London Olympic Park,designed by James Hitchmough

LA：James教授，您這次2019北京世園會(huì)項(xiàng)目的設(shè)計(jì)理念是什么？設(shè)計(jì)的重點(diǎn)突出表現(xiàn)在哪些方面？跟以往項(xiàng)目相比特別之處是什么？有沒有遇到什么難題？

James：我覺得最大的不同就是世園會(huì)是一個(gè)很大尺度的設(shè)計(jì)，將引來數(shù)量巨大的游客。我想我所有之前的設(shè)計(jì)都沒有這樣的經(jīng)歷，迎接大約1 500～1 600萬游客的到訪。這個(gè)數(shù)量級的游客總量給了我們一個(gè)非常棒的機(jī)會(huì)，來呈現(xiàn)不同的設(shè)計(jì)理念和創(chuàng)新的設(shè)計(jì)途徑。

我們這個(gè)花園的主題是新絲綢之路，靈感源自古絲綢之路，植物的選擇和平面布局也是遵從古絲綢之路的路徑，從東向西穿過中國干燥的中部草原，延伸至歐洲。花園的植被是基于植物群落的概念設(shè)計(jì)的。這些設(shè)計(jì)反映了植物在自然棲息環(huán)境的組合方式。在我們的花園里營造了5個(gè)獨(dú)特的棲息環(huán)境類型。

對于在中國做科研和項(xiàng)目來說，我們發(fā)現(xiàn)可用植物品種在中國的商業(yè)供應(yīng)是非常有限的，尤其在植物群落的設(shè)計(jì)當(dāng)中，我們并不能很容易地在市場上找到非常合適的種苗。所以，在我看來可能未來中國園藝發(fā)展的巨大瓶頸之一就是植物材料的商業(yè)供應(yīng)（圖16）。在明天（2017年12月2日）下午的大師論壇中，我將詳細(xì)說明適合大量商業(yè)供應(yīng)的本土和非本土物種及其巨大的挖掘潛力。植物材料商業(yè)供應(yīng)的匱乏將是生態(tài)植物群落設(shè)計(jì)推廣的最大阻礙。

中國應(yīng)該試圖去建立和發(fā)展一個(gè)景觀設(shè)計(jì)、園藝及苗圃產(chǎn)業(yè)相結(jié)合的產(chǎn)業(yè)鏈，一個(gè)生機(jī)勃勃、一個(gè)有創(chuàng)造力的產(chǎn)業(yè)聯(lián)盟，共同致力于研發(fā)和應(yīng)用多樣性的植物品種。中國是世界上自然植物材料最豐富的國家，也是文化多元化的國家，如果在未來能將這種多元化的特質(zhì)發(fā)散到園藝中，發(fā)散到種植設(shè)計(jì)領(lǐng)域，將會(huì)帶來非常激動(dòng)人心的改變。

5牛津植物園歐亞生態(tài)草花群落，詹姆斯·希契莫夫設(shè)計(jì)Eurasian mix in Oxford Botanical Garden, designed by James Hitchmough

LA：董教授，植物材料肯定是花園設(shè)計(jì)的最重要的一個(gè)因素，我們有很多邀請來的國外設(shè)計(jì)大師為我們奉獻(xiàn)出他們很好的設(shè)計(jì)思想，為我們奉獻(xiàn)精彩的園子，對他們的設(shè)計(jì)、他們的作品，您從專業(yè)的角度上有著怎樣的建議，對他們將來園子的實(shí)踐以及帶給我們生活的改變，您有著怎樣的期待？

DONG：借助于這次世園會(huì)，把國際知名的設(shè)計(jì)師請過來，我想其目的就是為了讓國人來學(xué)習(xí)?！八街?，可以攻玉”，發(fā)達(dá)國家實(shí)踐過的一些先進(jìn)的理念和設(shè)計(jì)手法，對于我們在快速城市化進(jìn)程中的城市建設(shè)確實(shí)有很重要的借鑒意義。至于設(shè)計(jì)園子，我覺得大師們來到這里所面臨的挑戰(zhàn)中，最大的問題可能仍然是植物材料。植物景觀設(shè)計(jì)有一個(gè)根本性的原則，就是因地制宜。設(shè)計(jì)師必須使用在當(dāng)?shù)氐淖匀画h(huán)境與氣候條件下能夠成活且長勢良好的植物，才能實(shí)現(xiàn)其設(shè)計(jì)理念或者設(shè)計(jì)思想。而我們園林植物材料的匱乏對他們可能會(huì)是一個(gè)巨大的挑戰(zhàn)。中國是世界園林之母，如之前所說，我們是世界上非常重要的觀賞植物資源聚集的地區(qū)，但我們也的的確確在植物資源開發(fā)和植物產(chǎn)業(yè)發(fā)展等方面還非常不足，所以要實(shí)現(xiàn)大師的好的設(shè)計(jì)理念，植物材料將是一大限制。因此無論這些園子最終通過何種方法建成，我希望借鑒他們這些設(shè)計(jì)理念、設(shè)計(jì)手法，以及呈現(xiàn)出來的成果，這不僅是給我們提供了一個(gè)學(xué)習(xí)的機(jī)會(huì)，也期待對我們的植物產(chǎn)業(yè)能有一定的推動(dòng)作用。當(dāng)然我也期待著這些世界各地的優(yōu)秀設(shè)計(jì)師借著這次契機(jī)，加深對中國傳統(tǒng)文化、中國傳統(tǒng)園林設(shè)計(jì)理念，對我們古人在人與自然關(guān)系處理方面的智慧的了解，將我們中國傳統(tǒng)文化中的精華向世界傳播。所以說，展會(huì)其實(shí)是一個(gè)雙向的過程，我們向他人學(xué)習(xí)，同時(shí)也借此傳播我們優(yōu)秀的傳統(tǒng)文化，這是我期待的另一個(gè)方面。

LA：通過剛才的介紹，我也了解到James教授，您是溫帶及地中海地區(qū)氣候環(huán)境下非常權(quán)威的生態(tài)草本植物群落專家，董教授您曾經(jīng)也研究過北京野生花卉在城市中的景觀應(yīng)用，那么我想問一下2位教授，對于草甸型景觀在北京地區(qū)的應(yīng)用持怎樣的觀點(diǎn)或態(tài)度？會(huì)和別的地區(qū)有哪些不同或者說存在哪些難點(diǎn)？

James：地處北緯40o左右的北京，正處于暖季型和冷季型草甸的過渡地帶。身在北京的人似乎都認(rèn)為北京的氣候?qū)χ参镞x擇和生長來說是具有很大挑戰(zhàn)的，但實(shí)際上，放眼全球，北京的氣候狀況在全世界范圍內(nèi)是很普遍的。例如，美國中南部的大部分地區(qū)與中國東北地區(qū)的氣候環(huán)境非常相似。因此，首先要尋找和研究非常適合北京氣候的本土及非本土植物。當(dāng)然，這需要大量的科研工作者的努力，不成體系的間斷性工作是遠(yuǎn)遠(yuǎn)不夠的。在全球氣候變化的大背景下，應(yīng)該根據(jù)北京氣候變化的趨勢，制定一個(gè)10～20年的計(jì)劃。

DONG：無論是草甸型景觀（我們以前可能叫野花草地），還是其他任何一種植物景觀的形式，我認(rèn)為在設(shè)計(jì)中都應(yīng)因地制宜地采用。我們國家過去這些年來在植物景觀營造方面出現(xiàn)的最大的問題就是跟風(fēng)，哪一種植物形式大家覺得好，或者領(lǐng)導(dǎo)覺得好，一窩蜂不管東西南北，不管什么功能的綠地，都去照搬，這是我最擔(dān)心的。沒有哪一種植物景觀的形式是錯(cuò)誤的，只有設(shè)計(jì)師用錯(cuò)了地方。所以，我建議設(shè)計(jì)師對于所謂的草甸型景觀同樣持以科學(xué)謹(jǐn)慎的態(tài)度。

LA：我們都知道，生態(tài)學(xué)思想是指導(dǎo)當(dāng)下城市景觀設(shè)計(jì)的重要指導(dǎo)思想，2位也都致力于生態(tài)城市中種植設(shè)計(jì)的相關(guān)理論和方法的研究，那么2位教授可否就自己在生態(tài)種植方向上的研究給我們一些介紹？

James：我研究的重心是建立極具視覺吸引力，且能保持長期觀賞效應(yīng)的多年生生態(tài)草本植物群落。同時(shí)，我研究景觀心理學(xué)，并試圖通過擬自然式的設(shè)計(jì)思路，讓更多的人能接受并喜歡上這種沒有設(shè)計(jì)痕跡的新自然主義設(shè)計(jì)。我們的研究和實(shí)踐經(jīng)驗(yàn)表明，如果我們能成功建立色彩豐富艷麗且觀賞周期很長的草花群落，即便那些曾經(jīng)不偏愛這種種植形式的人，最終也會(huì)轉(zhuǎn)而接受認(rèn)可，并給予很高的評價(jià)。因此，可以說我工作的一部分是不斷探索如何創(chuàng)造和維護(hù)這類植物群落，而另一部分是通過環(huán)境心理學(xué)的研究方法來探索人們對這種種植方式的階段性反應(yīng)（圖17）。

DONG：我目前主要的研究領(lǐng)域就是植物景觀的生態(tài)功能，包括不同尺度上植物材料的選擇和配置方式，在生態(tài)功能方面更為優(yōu)良，比如調(diào)節(jié)城市局地及微氣候功能，凈化空氣顆粒物的功能，也包括作為鳥類棲息地的功能。當(dāng)然，我也在很長一段時(shí)間都在致力于地域性植物景觀特征的研究，希望這些研究能為我們植物景觀設(shè)計(jì)提供切實(shí)的理論支撐。

LA：我們都知道，北京的氣候、土壤等環(huán)境要素和英國相比差異還是很大的，James教授您曾經(jīng)嘗試將生態(tài)草本植物群落研究應(yīng)用于北京市嗎？那您在這次2019世園會(huì)的生態(tài)種植設(shè)計(jì)中，有遇到瓶頸嗎？您覺得是什么原因造成的呢？您是如何解決的？

6 詹姆斯·希契莫夫長期致力于研究自然式生態(tài)群落中植物間的競爭關(guān)系James Hitchmough’s research focus is to explore the competition between plants for long-term compositon

James：通過考察研究北京及周邊地區(qū)中低海拔的自然植被生長情況，并對比與北京氣候條件相類似的世界其他地區(qū)的景觀特征，可以很好地了解和應(yīng)對北京目前的氣候挑戰(zhàn)。北京的自然氣候條件并不是獨(dú)一無二的，我考察了全世界很多地方，遍布各大洲，所以我能很好地把這些氣候相似的地點(diǎn)聯(lián)系起來，作為在北京設(shè)計(jì)生態(tài)植物群落的參考點(diǎn)（圖18）。

LA：通過這次世園會(huì)的實(shí)踐，請問James教授您對于生態(tài)種植設(shè)計(jì)有沒有一些新的看法和見解？

James：我們現(xiàn)在很難對整個(gè)世園會(huì)發(fā)表評論，但對于湯姆和我設(shè)計(jì)的展園來說，我們希望創(chuàng)造一個(gè)新穎獨(dú)特，但是充滿趣味、色彩艷麗，具有強(qiáng)烈自然景觀特征的花園。我希望在2019年能有一位中國博士生與我一起工作，采訪世園會(huì)的參觀者，了解他們對世園會(huì)不同植被類型 （包括我們的花園）的看法。

LA：最后，請2位教授談?wù)剬τ?019北京世園會(huì)的期望或寄語？

James：我在此期望2019北京世界園藝博覽會(huì)能取得空前巨大的成功，我也期望我們的花園能取得巨大的成功，受到大家的喜愛。

DONG：我希望2019世園會(huì)不僅會(huì)議本身能夠取得巨大的成功，也真切地期待著這次會(huì)議及其相關(guān)的各類活動(dòng)能夠切實(shí)影響到我們國家的產(chǎn)業(yè)，影響到我們大眾的生活。歸根結(jié)底，我們還是需要給大眾呈現(xiàn)最優(yōu)質(zhì)的園藝產(chǎn)品，才能夠改變我們的生活，所以我期待著這次會(huì)議能夠在這2方面都對我們國家起到很好的促進(jìn)作用。

致謝：感謝王一蘭前期準(zhǔn)備采訪內(nèi)容。

注釋：

圖1～7，16～18 由詹姆斯·希契莫夫與杭燁提供，圖8，10～12，14、15 由韓晶攝；圖9、13由蔡妤攝。

錄音整理：方小雨

翻譯：萬靜柯

校對：王晞月

（編輯/張雯娟）

Professor James Hitchmough proposed the theory of sustainable plant communities design with ecological concept, and completed the planting design in 20hm2of 2012 London Olympic Park.The whole design was based on planting design of herbaceous vegetation communities according to ecology, and the concept “ecological skin”came into being. Professor DONG Li introduced the concept of “natural degree” and “similar to the natural landscape”, on the basis of studying characteristics of zonal vegetation, and successfully hosted plant landscape ecological planning of the Beijing Olympic Forest Park which created the basic characteristics of zonal plant with good ecological function of forest park plant landscape.

James’ Dialogue with DONG was hosted by YIN Hao, the contributing editor of this Journal and associate professor. Thanks to the in-depth idea exchange and collision of the two professors,we’ve learned about some research directions and focuses remaining to be solved of ecological planting design in current urban construction,which pointed and lightened the way ahead of us.We should discover our own directions in later researches, practice or teaching, and practically provide effective theoretical guidance and technical support for further ecological planting design of urban environment.

LA:Landscape ArchitectureJournal

James: James Hitchmough

DONG: DONG Li

LA: Prof. James, your design is so natural that there isn’t any sign of design for a layman. Can you share us the inner logics in such approaches? What difficulties do you have to overcome in order to put it into force?

James: Some of the vegetation that I make does look some degree un-designed, if you are not familiar with looking at nature-like vegetation. In Chinese Landscape Architecture, most of plantings have been done in large blocks and that means have very ordered appearance. While my work tends to use either small groups or individuals repeated over and over again. So it is a different look, it does look more wild, does look more natural. At the same time it is designed to be beautiful, too. There are patterns and rhythms in it and most importantly it is often very flower rich and colorful over a long season on interest. It is this drama which makes it acceptable to many people (Fig. 1).

One of the reason that I was really interested in doing the Beijing Expo 2019 was to see how Chinese people respond when they see a whole garden designed according to nature-like principles. Very recently, I think about 6 months ago, the first scientific paper was published in an international academic journalUrban Forestry and Urban Greeningon what Chinese people think of meadows in Beijing. When you read this its clear that European and Chinese people share some similar views towards meadows and so perhaps we are not so different after all.

LA: When it comes to “nature”, in fact,Chinese tradition is natural, but professor DONG, as for the concept of nature, in your opinion, what kind of difference between Chinaand Britain ? Can you share with us?

DONG: When it comes to the word “nature”,it is a large topic. As professor Hitchmough said,I think we can classify it into two levels, so one is“nature of the Nature”, that is, “natural nature”,such as this kind of form “meadow” designed in landscape, it is actually imitated from the Nature,thus he hopes that his design looks traceless just like the real Nature; the other is “man-made nature”, in other words, it is the one which human beings learn from the Nature and use the Nature for reference to create it in man-made environment. Although it doesn’t really copy the original Nature, it indeed abides by the concept “Though it is made by man,it seems like being created by the Nature”, which is the nature expressed in our traditional Chinese garden. And it is not the real Nature, but the results by imitating it. Therefore, there is the concept“Learning from the Nature.” And it is the core aim in traditional Chinese garden. However, in the past few decades, China has taken some detours in the process of landscape planting construction,overemphasizing the human’s visual beauty, which has deprived much natural sense of our urban environment. I think this is the reason why professor Hitchmough said that Chinese planting design is in a regular way. Fortunately, we are now returning to the right direction, so I think it is very meaningful to explore this natural design idea and technique once more, and to apply them in the practice of rural and urban landscape planning design.

LA: We are together here for the Beijing Expo 2019. The theme of this expo is “Green Life, Good Home”. What’s your opinion?

James: Oh, I think it is fantastic opportunity to actually make some connections between these ideas. I think particularly the idea of having horticulture which becomes more ecological, at the same time, keeping its horticulture character.In most cases in cities, you need to maintain a balance between ecological and horticulture ideas to produce landscapes which perhaps everyone can really enjoy (Fig. 2). You asked me a few minutes ago about the problem of disorder and perceptions of messiness in my plantings. In some situations,you do need some planting which is more ordered,but this can be blended in with more disordered plantings, and to some degree this is what we will do at the Expo.

I think that it is really important when you have something like the Expo to exposes people to a very wide range of different and creative ideas about how plants can be used in urban places. And I think the Expo is going to have a really excellent opportunity to show people things and ideas they haven’t seen before, or are not very familiar with. Perhaps these types of experiences will gradually contribute to changing people’s attitudes to how things could look in cities. I think that is something we need to be better at than we are doing at present.

LA: Professor DONG, the theme of this Beijing Expo 2019 is “Green Life, Good Home”, perhaps because the meanings of our Chinese characters are more various, more extensive and more plentiful, do you have more understanding of this theme?

DONG: I think the theme “Green Life, Good Home” proposed in this expo is great. As you said,the potential meaning of every word in Chinese is extensive, for it is horticultural congress, so when we see the word “green”, we will firstly think it is a kind of color, but as a member working in landscape planting construction and other industries, we will naturally extended it to the meaning that “greenness”is dominated by plants making our life and work environment better. But actually “green life” is not limited in narrow meanings above mentioned, and its extensive meaning firstly should be expressed as a kind of concept which can contribute to our new understanding of the relationship between human beings and the Nature, and it is expressed by loving,respecting and protecting the Nature, so that we can develop with it harmoniously. In practice, we not only bring the Nature into our life environment and space we are living in, but also change our way of producing and living, including saving natural resources, using environment friendly production methods and so on. Well, only the concept and practice of “green life” should be introduced to every aspects of our life and production can it be real “wonderful life”.

7 由詹姆斯·希契莫夫設(shè)計(jì)的倫敦奧林匹克公園林緣生態(tài)景觀群落Woodland edge ecological planting community design in London Olympic Park done by James Hitchmough

LA: Professor James, as I know, there are various flower shows in the UK, and Chelsea Flower Show is especially well known worldwide.What aspects does British flower show attract the public? And how many effects does it have on people's life?

James: Yes, this is an interesting question. I think there is a big fundamental difference between China and Britain in that most British people have access to their own private gardens, so that means that they have very close relationship potentially with flower show. This is because they go to the flower show, which acts as a “shop window” they can see really interesting plants, they can buy them or they can buy them after the flower show, they put them in their garden. So they have this immediate opportunity to establish a long term connection with flowers. This is obviously, what the Chelsea Flower Show is about, it is all about show casing diversity. The British garden flora is very very big, you can buy online about 80,000 different species and cultivars of plants, today from your computer.And all the time, there are nurseries selling new plants originating from both the wild and from within horticulture to the people who want to use these in their gardens. And that drives froward changing diversity all the time. So in terms of Expo, because of these differences the Expo is a slightly different experience.But I think what will happen in time is these relationship will also develop very strongly in China, too.

Because in China people largely don’t have their own private garden.I think it makes it more important that public space has got some of these experiences within it. So instead of having very large scale of trees and woodland, you really also need to have lots of detailed plantings in contexts such as for example in situations like housing developments. You need to have a lot of seasonal change, a lot of colours and all the things that you otherwise get in the garden have really to be in maximizing the function of urban public space.

LA: In fact, when it comes to garden and horticulture exposition,China has been holding a lot of exhibitions in recent years, which is also changing our life and promoting the development of society.Professor DONG, how do you think China’s horticultural expos can better serve the public or change people’s life?

DONG: In fact China has a long history of gardening, but probably as for the context of modern horticultural exposition, China is not as good as Britain, because China do not have long history of horticultural exposition like the Chelsea Flower Show. However, after the reform and opening up,we have seen that there have been numerous horticultural expositions in china over the years. Although there are various problems in the process of holding expos, we are glad to see these problems are changing. In fact, until now these shows have played a major role in promoting the development of our industry and people’s knowledge of horticulture. Government attaches great importance to the horticultural exposition because of its high level.On one hand, by doing this, achievements of the exposition in developed countries and regions in the world will be widely presented, which means that it is bound to affect us from all aspects including its concept, technology and products. On the other hand, its achievements are not only limited in creating the exposition and decorating many practical achievements which can have direct in fluence on us in the future, but also include the varieties of activities held in society and relying on exposition organizations are plentiful,for example, this time we invite masters to our university for holding lectures and today’s TV interview, all of these have contributed to promote the whole society’s understanding of gardening, nature and ecological environment. I believe in the future, the achievements of the exposition will not only have positive effects on the public, government and professionals, but there will be more and constant achievements. Along with these, gardening will make people’s living environment and production space better and better.

8 北京奧林匹克森林公園植物景觀The Plant landscape of Beijing Olympic Forest Park

LA: The “birds and the whole biodiversity thing” depicts a beautiful environment with birds’ twittering and fragrance of flowers, an ideal scene for everyone. In recent years, Beijing has stepped up its efforts to improve environment, and is moving forward this beautiful vision. Can you give us some advices from the professional view in order to make citizens hear birds’ twitter outside windows and smell the fragrance of flowers entering their door?

James: I might start by talking a little bit about birds and the whole biodiversity thing. One of the issues in Beijing is that it is so enormous, so what happens nature wise in Beijing is often a function of its size. Because Beijing is so large, and because it is quite dense, what this means is it only has certain habitats within the city which would attract certain sorts of birds. In western European cities, people have a lot of gardens and these gardens serve as secondary function of providing habitats for wildlife. So you tend to see greater diversity of bird species typically in the European city than you do in the Chinese cities. And that’s simply because of the different land-use, scale and the huge area of gardens that support a lot of insects and birds.

There are a number of ways as to how we can improve the animal biodiversity of Chinese Cities. One of the most obvious ways is to try to build in more complexity in some of the structure plantings within the city. Beijing has the very large areas of tree plantings. But in great deal of them are: a) quite young; b) often the same species. If there is more diversity of species, and you are more spatially complex, then you will support more animal life. That’s the first thing I think. I think the second thing is some of the issues are best addressed by really large scale planning where you need to have more green corridors running into the city and when land is developed, try to maintain the percentage of these so that these nature conservation corridors can deliver some of those experiences and opportunities (Fig. 3).

LA: Speaking of “birds and the whole biodiversity thing”, Professor DONG, you just mentioned this beautiful vision at the Third Forum on Landscape Plants and Human Settlement Construction several days ago. As far as I know, you have energetically explored and researched these years, so please tell us some of your achievements through deep thinking and professional researching.

DONG: Indeed, we expect the “birds and the whole biodiversity thing”. Actually, human beings used to live in environment like that. Today, I put forward this dream and vision again, which may be related to the fact that we took wrong path in the past so that we have lost this kind of environment.Exactly as what Professor Hitchmough has said,it’s more obvious in Beijing and other big cities in China. With large area, dense population and lower biodiversity caused by the problems of ecological environment construction, our city lacks beautiful environment just like the environment with the scene that “birds twitter and flowers bloom with fragrance”. To change this situation, what should we do and what we can do? As a plant landscape planner and designer, I have to say that plant landscape can be planned and designed, but birds can’t. What we can do is to plan and design a good plant landscape to provide a good habitat for birds and other animals to live in. Only in this way can we attract them and make them settle down. So when it refers to biodiversity, plants should be thought first, because the key is to keep the diversity of plants and plant landscape. Brie fly, the diversity of plant is the variety and richness of species, which can provide a habitat for birds where they can eat, nest and breed. Besides, the diversity of plant landscape is also very important. Different types of plant con figuration are the indispensable elements in birds’ habitat. Which birds need multilayer and complex plantation structure, and which birds need tidal flat wetland, these are the questions needed to be solved specifically. Of course, there is one more important aspect, that is, the rationality of green space layout which includes the types of green spaces, such as corridors and patches, and their rational relationship pattern. Only achieving all above-mentioned can we lay a foundation to attract more birds and build the environment where biodiversity is more. Ultimately, the optimal human settlement is where human and the nature live in harmony. Our purposes are not only to attract animals, but also for ourselves’ living, that is, we live in city, and city is also supposed to be an optimal living space for human beings, so harmonious existence between human beings and the nature is our ultimate purpose.

LA: Both of you are experts in the field of plant landscape planning and design,based on your research, teaching or practice projects, could you talk about how important and what the improvement of planting design to our urban living environment is?

James: I think the form of the planting design is less important that the delivery of experiences to people that are interesting and meaningful. What people need in urban environments is a sense of seasonal change, and a series of events be it through flowering or leaf colour change which means there is always something interesting and stimulating happening. The trick is how to provide this in ways that really work for the people in question (Fig. 4, 5).

DONG: The improvement of plant landscape for unban residual environment is expressed in all aspects. And the most obvious situation citizens can feel is that green trees and various flowers make unban residual environment more beautiful, for example, when they relax in parks in summer, they can find shady and comfortable space for their rest and visiting. Of course, plants can produce many benefits which we don’t necessarily see or realize.Overall, apart from beautifying environment, the signi ficance of plants to unban residual environment is also embodied in improving our ecological benefits, such as cooling temperature, defense and protection, purifying air, isolating noises, and providing habitats for other animals. Meanwhile,plants also have important cultural signi ficance that they are the carrier of regional culture inheritance,and this kind of significance may be have an in fluence on citizens, but it does have.

LA: In the practices of specific projects,both of you had undertaken the ecological planting design of large city park. Professor James was the planting designer for 2012 London Olympic Park, and professor DONG designed the ecological landscape planting for 2008 Beijing Olympic Forest Park. Could you respectively talk about some of the guiding ecology theories in your work or have you encountered any troubles and how they were settled?

James: The key ecological theories in my work are generally how plants compete with one another and how this effects the long-term composition of those plantings. The levers we use to get the best outcomes are often plant selection and design of plant communities to reduce the likelyhood of a vigorous species out competing its neighbours (these species are used at low densities to reduce these effects), and secondly the use of low nutrient soils to slow down the growth of species to reduce competitive effects. But then of course this causes problems with clients who want very rapid growth, which is something you cannot have whilst at the same time minimising competitive loss (Fig. 6, 7).

DONG: I was invited to participate in the team of overall planning of Beijing Olympic Forest Park in 2005, and apart from being an expert member in the team, I was also engaged in the task of plant landscape ecological planning of Beijing Olympic Forest Park. It should be said that the project which is in such a huge scale more than 700 hm2and called “forest park” is a big challenge to us. Through thinking it over at that time, I think now that it is called “forest park”,the construction of plant landscape in this park should be the most important content, and plant landscape should meet at least two points: the first point is that it should look like forest. What are the features of forest? Which forest should it look like? How do we make it look like forest?The first feature of forest is naturalness, second is that it looks like forest in this zone, and the third is that how does it look like forest. We introduced the design concept of similar to the nature and natural degree, and we studied structure characteristics of vegetation under the condition of different natural degrees in Beijing region,which laid a foundation for plant landscape planning and design of forest park. The second point is that it should have some functions like real forest. We dare not say the patches of manbuilt green land in cities can have the function like the real forest in the nature, but at least we hope it can have part of functions, and what is the most important function of the forest? That’s habitat. So when in 2005 we studied the zonal animals’ demand for plants in Beijing from the point of view of habitat, of course, it was a very preliminary research and it is one of basis that we choose plants. Of course, many other aspects are also considered including adaptability, ecological bene fits, culture and so on. It should be said that these original studies are not in vain, now forest park indeed have played a huge role in animals and especially birds’ habitat, and currently there has appeared more than 200 kinds of birds flying here (Fig. 8-15).

LA: What is your design concept in the coming Beijing Expo 2019? What makes it a special project comparing with the previous projects? Have you encountered any problems in the whole process?

James: Well, in terms of what makes the Expo difference, one of the things is it is founded on a large scale and will have huge number of people come to it. I don’t think I’ve ever designed anything which would have 15～16 million people coming to look at it. This level of visitors means a fantastic opportunity to communicate some new or unfamiliar ideas.

Our garden the “New Silk Road” for the Expo is inspired by the idea of the Silk Route, crossing the dry central steppes of China from east to west.The vegetation for the garden is based upon the idea of designed plant communities. The design of these re flects the organization of plants in natural habitats. Within our garden there are essentially five distinctive designed habitats.

11～13 北京奧林匹克森林公園植物景觀The Plant landscape of Beijing Olympic Forest Park

One of the things we have experienced when we has been designing plantings in China, and in particularly when we want to make plant communities,we have often struggled to find plant material commercially available for us to use. So I think this is a major additional difficulty in China (Fig. 16). I will speak more about this tomorrow afternoon at the designers conference about how both with native and non-native species the range of plants available is actually relatively small in relation to what could be available. And this does limit you when you are trying to design vegetation along community design principles.

14、15 北京奧林匹克森林公園植物景觀The Plant landscape of Beijing Olympic Forest Park

One of the challenges for China is to develop a Landscape Architecture, Horticulture and nursery sector that is dynamic, creative and really wants to work with a diversity of plant materials. China is a very diverse place naturally and culturally,and it would be great to reflect that diversity in horticulture in the designed plant world.

LA: Professor DONG, plant material is definitely an important element in the design of garden. We have invited many famous foreign design masters to give their good design ideas and present their beautiful gardens. So as for their designs and works, what’s your suggestion in a professional way? And what’s your expectation of their practice of gardens? And what kind of changes it would bring to our life?

DONG: Through this exposition, many internationally famous designers are invited.I think its main purpose is to let domestic designers learn from them. “Foreign stones may serve to polish domestic jades”. Some of the advancing practiced theories and design methods in developed countries have important reference significance for the urban construction in our rapid urbanization process. As to designing gardens, I think the biggest challenge may still be plant materials. One of the fundamental principles of designing plant landscape is to adjust measures to local conditions. Designers must use the plants that can survive and grow well in local natural environment and weather conditions. Only in this way can they make their design philosophy or design thinking come true. Lacking of garden plant materials may be a big challenge for them.China is the mother of the world gardens. As what have been mentioned before, China is a very important area that enjoys rich resources of ornamental plants, but China is indeed not very suf ficient in plant resources exploitation and plant industry development. Therefore, the lack of plant materials will be a restriction to achieve the good design philosophies of design masters.So no matter how these gardens will be built eventually, I hope their design philosophies, design methods and the achievements would not only provide a learning opportunity for us, but also can promote our plant industry in some extent.Of course, I am also looking forward to that the excellent designers from other countries, through this opportunity, can have a deeper understanding of traditional Chinese culture and traditional Chinese design philosophy of gardens as well as a better understanding towards the wisdom of our ancestors that is shown in dealing with the relationship between them and the nature. I hope the essence of our traditional Chinese culture would be spread throughout the world. Therefore,exposition is indeed a two-way process, during which we learn from others and at the same time spread our excellent traditional culture. This is another aspect that I expect.

LA: Through the previous introduction,professor James, I learned that you are an authoritative expert in the design and management of extensive communities of nature-like herbaceous vegetation,and professor DONG you had carried out researches regarding the wild flower application in urban landscape of Beijing.So, I want to ask, you two, what do you think about the application of meadow landscape in Beijing area? What are the differences or difficulties comparing with that of other areas?

James: At around latitude 40oN Beijing is on the transition zone between warm season and cool season grasses; people in Beijing seem to think that there climate etc. is tough for plants, but of course the climate of Beijing is very common around the world. Much of the central southern regions of the USA for example are climatically very similar to North East China, so the big issue in Beijing is to identify plants that are really well suited to the Beijing climate. This requires an extensive research effort, not just a bit of work here and a bit of work here, but a 10-20 year plan in which the inevitability of large changes to the climate of Beijing is factored in.

DONG: Whether meadow landscape, what we may call wildflower meadow before, or the form of a kind of any other plants landscape, I think that in the design we should adjust measures to local conditions to adopt it. In past years the biggest problem of our country is following the trend in the aspect of plant landscape construction.No matter what kind of plant is admired by everyone or leaders, we will copy it in a rush regardless of what it is and what functions of green space have, which is my worry most. There is no fault form in plant landscape, but only designers use it in wrong place. So I suggest that designers should hold scienti fic and cautious attitude toward your so-called meadow landscape here.

LA: As we all know, ecology theory is one of the most important guiding thoughts for present urban landscape design, you two have also concentrated on relevant theories and methodologies of planting design in ecological city, so, could you give us some introduction of your own researches?

James: My research has centred around whether it is possible to maintain hyper-flowery perennial herbaceous vegetation in the long term, as a means of getting people who might not like the disorder of meadow like vegetation to buy in to this.Our research and practice experience shows that when meadow like vegetation is very colourful over a long season it can be valued even by people who would otherwise find it unaccpetably messy. So my work has partly been about how to make and maintain this type of vegetation and secondly exploring human respose to this through Environmental Psychology type methodologies (Fig. 17).

16 很多有價(jià)值的本土物種沒有商業(yè)供應(yīng)（此照片為內(nèi)蒙古野外考察時(shí)拍攝）Lots of valuable native species are not available in market (this is a pic from field trip in Inner magolia)

17 城市人需要極具視覺吸引力，且能保持長期觀賞效應(yīng)的多年生草本植物群落Hyper-flowery and long-term perennial herbaceous vegetation is important to citizens

18 在劍橋植物園內(nèi)使用本土及來自于氣候環(huán)境極相似地區(qū)的植物Use native species and non-native species from climately similar areas to create vegetation in certain climate in Cambridge Botanical Garden, designed by James Hiychmough

DONG: At present, my major research is ecological functions of plant landscape, including the selection of plant materials and con figuration mode at different scale, for the purpose of making ecological functions more excellent, such as regulating the function of urban regions and micro climate, functions of purifying air particulate matter, and including as a function of bird habitat.Of course, for a very long time I was also working on the research of regional characteristics of plant landscape, hoping it can provide our plant landscape design with practical theory support.

LA: As we all know, the climate, soil condition and other environmental elements of Beijing vary a lot from that of Britain, Professor James, have you tried applying ecological herbaceous plant community to Beijing? Have you encountered bottlenecks in the planting design of the Beijing Expo 2019? Why and how did you settle them?

James: You can get a pretty good idea of how to get around the climatic challenges of Beijing by looking at what is growing naturally in the region at low to moderate altitudes and secondly by looking at the landscapes of the other parts of the world I referred to earlier that are very similar to Beijing.Beijing is not unique, I have travelled very extensively so I am connected to these other places as reference points (Fig. 18).

LA: Through the practice in this Beijing Expo 2019, do you have any new ideas and understandings about ecological planting design to share with us?

James: Its difficult to comment on the Expo as a whole but it terms of Tom and my parts, we hope to create a garden that will be very unfamiliar yet fascinating, quite strongly disordered and natural looking but also very colourful with a long season of positive seasonal change. I hope to have a Chinese Ph.D. student working with me by 2019 who will interview many visitors to gain an insight into what they think of the different vegetation types (including our garden) at the Expo.

LA: Finally, could you please talk about your expectations or wishes to the Beijing Expo 2019?

James: Yes, I hope the Beijing Expo 2019 is enormously successful and I also hope our design is enormously successful, too.

DONG: I not only hope that the Beijing Expo 2019 can succeed wonderfully, but also sincerely hope this exposition and its related activities can actually have influence on our national industry and public life. Ultimately, we need to present the best garden work to the public, and only in this way can we change our life. So I expect that this exposition can facilitate our country from the two above-mentioned aspects.

Acknowledgement:Thanks to WANG Yilan for her contribution to this interview during early preparation period.

Notes:

Fig. 1-7, 16-18 are provided by James Hitchmough and HANG Ye; Fig. 8, 10-12, 14, 15 are photographed by HAN Jing; Fig. 9, 13 are photographed by CAI Yu.