增进城市地区生物多样性—以新加坡模式为例

著：（新加坡）林良任 （新加坡）陈莉娜 （新加坡）鲁·艾德里安·福铭 译：邢子博 校：张天洁 （新加坡）李天娇

近年来，新加坡已被公认为第一世界国家中成功的“花园城市”，这里的城市基础设施被纳入绿化网络结构之中。在政治意愿和远见的结合推动下，通过专业和有素养的技术机构支持，新加坡半个世纪以来一直致力于绿色城市景观的实践（图1）。

在过去十年中，关于城市及其人口如何与周围和内部的自然生态系统相互作用，并从中获益这一话题，人们的关注点在发生转变。城市规划师们开始致力于推广“自然城市化”和“自然设计”，以此来阐释在城市景观设计中，如何将绿化和生物多样性融入基础设施。新加坡一直在引领这一新兴趋势，处在城市绿化战略的前沿。这不仅包括简单的舒适性种植设计，还制定以科学为基础的战略来保护自然生态系统，并在高度城市化的岛屿国家中和谐地支持生物多样性。

1 背景

当史丹福·莱佛士爵士（Sir Stamford Raffles）于1819年登陆新加坡时，这里的大部分地区都被原始的低地龙脑香林、淡水沼泽、红树林等覆盖。

不同于普遍的认知，新加坡原始森林消失的原因并非现代城市的发展，而是19世纪农业的出现。由于农业的快速发展和聚集，到1930年，新加坡超过90%的天然林已经被清除[1]。1965年新加坡独立时，继承了一个几乎没有原始森林覆盖的岛屿，只剩下自然生态系统的若干碎片。自独立以来50年的时间里，新加坡是如何在极高人口密度下，从一个景观贫瘠的地区转变为获评MIT Senseable City Lab's Treepedia绿色景观指数高的城市之一的？

2 现代新加坡—由“花园城市”转变为“花园中的亲生态城市”

“我们在建设，我们在进步，但是没有什么比建成东南亚最干净和绿化的城市更具特色和意义的成功标志了。”

摘自李光耀先生于1968年10月1日在首次举办的新加坡清洁运动中的演讲

1963年6月16日，新加坡植树活动中，当时在任总理李光耀先生种植了一棵黄牛木（Cratoxylum formosum）。这一历史性事件标志着新加坡向着花园城市绿化之旅迈出了第一步。在最高政治层面，有一个强烈的愿景和清晰明确的指示，即新加坡应该是一个干净的“绿色花园城市”，并成为当时第三世界死水中的绿洲。李光耀先生认为，绿化和清洁不仅是新加坡高效和良好治理的显著表现，还应该让社会各阶层都能获得利益，而不仅是富人阶层。为了让新加坡绿化程度达到更高水平，国家公园局提出将新加坡打造成花园城市的愿景。

21世纪，新加坡的绿化和自然保护，以科学方法为基础，了解绿色植物和生物多样性并从中受益。新加坡认为多样的生态系统和栖息地及所有物种是其丰富而古老的自然遗产不可分割的一部分。新加坡也从最近的研究中得到启示，这些研究表明绿色和生物多样性城市具有很多优势—例如干旱和洪水等极端天气事件的恢复和缓解；空气污染物的减少；公民身心健康的改善—为一个有弹性、可持续和宜居的国家做出贡献。

基于此，新加坡在第一世界经济中建立了一个令人印象深刻的绿色矩阵—一个“花园中的亲生态城市”。新加坡是一个岛屿上的城市国家，陆地面积约719 km2。尽管保持着高度的城市化，新加坡仍然拥有丰富的原生物种，包括约2 215种植物（记录在册的）、61种哺乳动物、403种鸟类、334种蝴蝶、131种蜻蜓、800多种蜘蛛[2]583-609。海洋生物多样性同样丰富，包括12种海草、255种硬珊瑚和200多种海绵（表1）[3]。更令人惊讶的是，新加坡不断发现过去未曾被记载的新物种，或重新发现被认为已经灭绝的物种。过去五年所记录的480多种动植物就证明了这一点[4]。

1 新加坡武吉知马自然保护区鸟瞰Aerial view of Singapore from above Bukit Timah Nature Reserve

2 新加坡自然保护区Nature reserves in Singapore2-1 武吉知马自然保护区Bukit Timah Nature Reserve2-2 中央集水区自然保护区Central Catchment Nature Reserve2-3 双溪布洛湿地保护区Sungei Buloh Wetland Reserve2-4 拉布拉多自然保护区Labrador Nature Reserve

未来的目标不仅是在土地受限、建筑密集的景观中，确保新加坡丰富的本土生物多样性持续发展，而是创造一个“城市生态系统”。在这里，基础设施和人类活动与生态系统服务和绿化提供的益处相互协同。生物多样性的解决方案必须以多学科、跨部门和综合方法为基础，所有利益相关方全面参与，并得到强有力的科学研究支持。

3 自然保护蓝图

以基于科学原则为指导，新加坡自然保护蓝图（The Nature Conservation Masterplan，简称NCMP）致力于集合、协调、巩固和增强新加坡生物多样性保护工作[5]。通过加强生态联系来建立生态弹性，这将有助于保护本土生物的多样性和适应气候变化带来的影响。

NCMP包括4个重点：1）核心栖息地保护；2）栖息地强化和恢复，物种复育；3）在保护生物学和规划方面进行稳健可靠的研究；4）社区管理和外展活动。以上所有的保护举措都包括海洋、沿海、陆地生态系统，覆盖生态系统、物种和基因各层面。

3.1 保护核心栖息地

核心栖息地保护主要目标是保护和加强核心生物多样性区域，保护和增强缓冲区，在新加坡加强和管理其他绿化节点，发展生态联系，并将自然与更广阔的城市景观融为一体。

核心生物多样性地区包括：1）武吉知马自然保护区（图2-1）；2）中央集水区自然保护区（图2-2）；3）双溪布洛湿地保护区（图2-3）；4）拉布拉多自然保护区（图2-4）；5）包括乌敏岛和姐妹岛海洋公园在内的自然区域，这些地区拥有新加坡大部分的原生物种，是关键的基因存储库和来源。多样化的生态系统都体现于这些核心地区，包括低地龙脑香林、次生林，淡水沼泽、溪水和河流、草原、红树林、岩石海岸、沙质海岸、潮间带泥滩、海草草甸、珊瑚礁、开阔水域等。新加坡的用地非常集约紧凑，这些地区距离樟宜国际机场都只有40 min的车程。没有天然腹地的新加坡是世界上少数几个核心自然保护区位于城市内的国家。

为了缓解这些重要核心区域的边缘效应，如防止干燥条件、强风和外来入侵物种的渗透，核心区域附近被指定为自然公园。例如，中央集水区自然保护区周围有策士纳自然公园、正华自然公园、春叶自然公园、汤申自然公园、温莎自然公园、牛乳场自然公园、海希德自然公园、射靶场自然公园等（图3）。同样，双溪布洛湿地保护区的扩建包括克兰芝沼泽、万礼红树林和滩涂，这有助于有效保护生物多样性所需的临界标准。

在核心区域之外也发现了许多珍稀濒危物种。为了更全面地保护这些物种，对其他绿化节点生物多样完整性的增强工作同样受到特别关注。

为了对抗自然栖息地的碎片化，上面提到的缓冲公园以及生态连接网络，都是作用于扩大本土动植物生态空间的关键因素。缓冲公园增加了核心自然保护区的生态足迹，生态连接提供了一个岛屿范围的基质，以提供原生动物觅食和繁殖所需的空间，并使原生植物得以分散。正是基于这一原则，通过利用地理信息系统（GIS）建模技术追踪阻力最小路径等方法，确定了核心区域的潜在生态连接。横跨313 km的公园连道，80 km的自然连道[6]—Eco-Link @ BKE（图4），以及多层种植道路与本土植物物种（图5），这是为扩大新加坡生态连通性而实施的一些举措。此外，立体绿化项目是鸟类、蝴蝶、蜻蜓和其他飞行动物的垫脚石。

3 中央集水区自然保护区周围的自然公园Nature parks surrounding the Central Catchment Nature Reserve

4 Eco-link @ BKE是一条架空生态走廊，旨在恢复两个自然保护区之间的生态连接The Eco-link@BKE,an overhead ecological corridor constructed to restore ecological connectivity between two Nature Reserves

5 多层种植创造了多种生态位，已应用于路边绿化Multi-layered planting that creates multi ecological niches has been applied to roadside greenery

为了增加对丰富的海洋生物多样性的关注，制定了海洋保护总蓝图（MCAP）。MCAP强调的其中一项举措是建立姐妹岛海洋生态园（SIMP，图6），该公园位于世界上最繁忙的港口之一的常规航道中间。多主体建模研究结果支持SIMP的选址，因为它是海洋生物的潜在有效源礁。海洋生物的卵或幼虫可以分布在新加坡的所有沿海和海洋区域。SIMP的目标是促进保护、研究、教育和外展。目前SIMP正在建立一个原位硬珊瑚储存库，目的是保存新加坡发现的所有本地现存硬珊瑚物种，其数量可达全球800多种硬珊瑚物种的30%以上。

国家公园局还制定了综合城市沿海管理（IUCM）计划，以促进沿海地区的协调活动[7]。这种模式已在诸如东亚海洋环境管理伙伴关系（PEMSEA）等区域论坛上分享。随着更多沿海城市的城市化推进，这一模式将愈加凸显其价值。

3.2 加强和恢复栖息地并协助物种恢复

多年来，由于人类的活动和土地利用的变化，城市的自然景观不可避免会出现退化。随着越来越多的证据表明：生物多样性提供了有益人类健康和福祉的生态系统，有必要通过栖息地恢复、增强和创造来修复自然区域的功能完整性。因此，NCMP的第2个重点是核心区域，缓冲区、其他绿化节点和生态连接的栖息地增强及恢复以及物种复育。

除了在自然区域实施之外，栖息地增强技术也适用于城市景观单一或生物多样性贫乏地区。乌节路是新加坡最繁忙的购物区之一，与之相交的一条小路布满了吸引蝴蝶的植物。在新加坡植物园学习森林（图7）中修复了一个被称为吉宝探索湿地的淡水湿地栖息地，该森林位于新加坡植物园的缓冲区，是一个联合国教科文组织世界遗产。它是受威胁的淡水动植物的避难所，使水文过程得以恢复，低地雨林得以再生，人们得以更接近自然[8]。

2019年1月，国家公园局公布了森林修复计划，该计划旨在通过恢复生态过程和加强生物多样性、生态连通性来增强原生雨林的复原力。该行动计划还希望协助早期次生林继续成长为更成熟和多样化的雨林，从而改善生物多样性的栖息地。方法包括：种植可以固定氮的原生植物，以自然地改善土壤条件并且吸引传粉者和传播动物，清除杂草以协助再生、引入主要的雨林物种等。

在像新加坡这样物种丰富的小岛上，大部分动植物种群都将不可避免地面临灭绝的威胁，特别是当地特有物种。这些物种已经得到了额外的援助，以确保其数量能够达到可持续的水平。例如，世界上最大的兰花—老虎兰（Grammatophyllum speciosum，图8），曾被认为在新加坡已经灭绝。随着在苗圃的繁殖和全岛的广泛种植，老虎兰在新加坡的保护状况得到了极大的改善。当这些兰花在公园、花园和道路上盛开时，它们总会使人心情愉悦。同样，新加坡蕊木（Kopsia singapurensis）是仅在马来西亚半岛和新加坡的淡水沼泽森林栖息地中生长的物种，并且在当地处于极度濒危状态。该物种的迁地保护项目已经到位，在新加坡植物园和巴西班让苗圃进行扦插，并在森林改良和恢复项目中种植，例如铁路走廊的重建项目。

东方斑犀鸟（Anthracoceros albirostris，图9）曾经一度被认为在新加坡已经灭绝。1997年，一些犀鸟飞到乌敏岛（Pulau Ubin）筑巢。研究表明，限制该鸟类繁衍的因素是适合筑巢地点的缺乏。在几个不同位置的高大树木中设立智能巢箱，随之该种犀鸟数量现已增加到100多只。

另一个在新加坡重现的魅力物种是滑毛江獭（Lutrogale perspicillata，图10）。在新加坡，它曾经被认为已经灭绝，20世纪90年代中期才重新出现。沿海栖息地以及市政水道（如碧山—宏茂桥公园和滨海湾）的强化促进了该物种的重现。如今，滑毛江獭的数量超过70只。包括国家公园局的新加坡水獭工作小组与民间水獭保育组织同心协力，以多学科、利益相关者相互配合的方式监测追踪水獭的数量及动向，保护该物种。

目前的物种复育计划包含了新加坡特有的新加坡淡水蟹（图11）。这种溪蟹被国际自然保护联盟列为全世界前100种受威胁的物种之一。国家公园局正致力于人工繁殖，转移部分群种至适当的溪流及研究该物种的生态需求。至今，已经有超过300只小螃蟹在人工繁殖技术下成功孵化。

值得注意的是标志性的杯状大海绵（Cliona patera）在新加坡的重新发现。该物种曾一度被认为已经灭绝了近一个世纪。直到1990年，一个个体在澳大利亚海岸被打捞上来。2011年新发现了2个活体样本，随后又发现了3个样本，使新加坡成为目前世界上唯一拥有该野生海绵已知样本的地方。5个以上的杯状大海绵被转移到姐妹岛海洋生态园附近的最佳生存地点，它们的生长和健康状况被持续监测。

6 姐妹岛海洋生态园The Sisters' Islands Marine Park

7 新加坡植物园学习森林修复的淡水湿地栖息地The restored freshwater wetland habitat at the SBG Learning Forest

8 老虎兰，世界上最大的兰花The Tiger Orchid,largest orchid in the world

3.3 保护生物学与规划的应用研究

第3个重点包括各种举措，例如，综合调查[2]3-17，[9-11]以及对生态系统和物种的长期监测，定量生态研究，基于科学的政策制定和管理规划。国家公园局研究和运营工作的一个关键优势是不断应用最新技术，包括地理信息系统、多主体建模、数值建模、基因组学、3D建模和激光雷达等。新加坡生物多样性的保护和研究是在不同层面上进行的：整个国家层面、景观层面、地表层面甚至下至微观和基因层面。

在整个国家层面，卫星图像是国家公园局开展各种研究项目的一个非常强大的工具。从确定新加坡绿色覆盖的真实性，到为连通性研究辨识绿色走廊，甚至是做卫星图像的光谱分析以检测不健康的森林斑块，国家公园局利用这项技术作为规划和决策支持工具（图12）。

在景观层面，另一套高科技工具也被应用于规划、保护和树木栽培等多个领域。整个街景的激光雷达模型用于估算树冠的生长速率和确定适当的修剪措施。研究沿海动植物（包括滨鸟、珊瑚幼虫和红树林繁殖体）运动的多主体模型可以保护作为觅食地或增长来源的重要栖息地。无人机技术也已成为绿化研究和运营的重要技术工具。空中无人机是一种低成本的解决方案，可以帮助追踪栖息地以及再造林随着时间推移的增长状况，调查兰花和其他附生植物的树冠，甚至调查树木的缺陷。

在地表层面，生物多样性调查仍然是保护研究的关键组成部分。近期陆地和海洋生态系统调查显示，已发现至少3个新的当地独有植物物种，即Zingiber singapurense（姜属的一种）、Hanguana rubinea（匍茎草属的一种）、Hanguana triangulata（匍茎草属的一种）、150余种长腿苍蝇和超过100种未发现过的海洋生物。尽管新加坡是世界上最繁忙的港口之一，通过确保在海洋航道之外有足够的海洋栖息地，并且在海洋环境中开展发展项目时积极采取缓解措施，新加坡海洋生物多样性的丰富性得到了保障。新物种的持续发现表明新加坡尚未达到新物种发现曲线的稳定期。同样令人鼓舞的是，许多以前被认为已灭绝的植物物种，即50年来都没有记录的物种，已经通过系统性和强化后的实地调查被重新发现（图13）。

技术进步也改变了生物多样性调查的格局。尤其是红外相机和夜视镜的使用大大推动了森林脊椎动物的夜间研究，因为这些动物大多数只在夜间活动（图14）。其他调查方法的创新包括在陆地或海洋环境中使用声学传感器监测动物的发声，或与声呐装置结合，确定沿海和海洋物种的种类和个体数量，譬如海豚、鲸鱼甚至鳄鱼。

在详细了解新加坡的物种知识后，展开了对物种之间错综复杂的相互关系定量研究和生态研究的课题。利用最新的预测建模工具对这些复杂联系的结果进行分析，设计出更好的管理计划，并促进基于科学的决策。

在分子和遗传层面，DNA分析作为一种先进的调查方法，正在成为进一步研究新加坡和区域内其他地区动植物物种之间关系的手段。为了更好地了解物种的遗传可行性，对新加坡莱佛士叶猴的种群进行了遗传研究。环境DNA或环境“eDNA”研究目前正在进行，目的是部署该技术以监测新加坡水域的各种海洋生物，包括可能的外来入侵物种（图15）。

3.4 社区管理与自然界的拓展

NCMP的最后一个目标是通过自然社区（CIN）计划增进整个社区的生态包容性。CIN是2011年9月启动的一项全国性运动，旨在联系和促使社区中的不同群体成为新加坡自然遗产的共同拥有者，包括家庭、独立人士、教育和研究机构、大小型公司、非政府组织以及政府机构。

CIN的一些举措包括：1）将生物多样性纳入教育系统的各个层面；2）制定强有力的公民科学计划，使公众、学校、科学家和业余自然学者参与到年度“生物多样性速查”，观察鸟类、蝴蝶、苍鹭和蜻蜓活动（图16）；3）学校组织绿化活动，以增进生物多样性的实践经验，为学生提供实践生物多样性的调查，记录生物多样性和改善学校周围栖息地的机会；4）维护新加坡生物多样性的数据库和分布地图，公众使用移动应用程序“SGBioAtlas”轻松地记录生物多样性；5）按顺序组织一年一度的生物多元节（FOB），将有关新加坡自然遗产和生物多样性的知识传播到社区的中心地带。

国家公园局于2019年5月18—26日举办活动，FOB将作为最后的压轴。预计将有3 000名参与者参加全国范围的“bioblitz”活动，覆盖包括海洋公园在内的80多个地点。

此外，还有许多以社区为基础的平台可以让公众参与绿化和生物多样性保护，包括锦簇社区、乌敏之友网（FUN）、乌敏岛盛会和公园之友。这些不同的计划和平台共同运作，促使所有群体与新加坡人进行广泛而深入的互动。国家公园局还鼓励人们积极参与项目，甚至赞助企业的员工也作为实践志愿者参与他们资助的项目。

4 监测的成果—新加坡城市生物多样性指数

国家公园局是生物多样性国家联合公约（CBD）的国家联络点。为了记录在绿化和生物多样性保护方面的成功，并支持其他城市建立一套共同的成功指标，国家公园局与CBD秘书处合作，联合“生物多样性地方政府和城市的全球伙伴关系”，共同开发城市生物多样性指数。以上也被称为新加坡城市生物多样性指数（SI），它是一种评估城市生物多样性工作的自我评估工具[12]。全球有25个城市已经成功应用了SI，大约40个城市正处于应用SI的不同阶段。

5 区域与国际承诺

国家公园局也是参加联合国气候变化框架公约会议的新加坡代表团成员。2015年7月4日，在德国波恩举行的世界遗产委员会第39届会议期间，新加坡植物园被列为新加坡首个世界遗产，这体现了对文化遗产的奉献精神。为了表彰其对新加坡生物多样性保护的重大贡献，国家公园局荣获2017年联合国教科文组织苏丹卡布斯环境保护奖。

由国家公园局管理的双溪布洛湿地保护区和武吉知马自然保护区已被认定为东盟遗产公园。

6 结论

综合、长期的调查和监测表明，新加坡拥有丰富的本土生物多样性。自然保护区和自然区域的维护，以及正确的公园管理（公园连接网络）和街景管理的方式，为新加坡本土生物多样性繁荣发展提供了合适的栖息地环境。此外，通过立体绿化和垂直绿墙将保护区拓展到空中，并将国家公园局的保护工作扩展到沿海和海洋环境区域，为自然城市的理解和实践增加了多个维度的可能性。

这与两个第三方的独立评估一致。首先，Treepedia以绿色视图索引（GVI）的形式测量城市中的冠层覆盖。在他们分析的前27个城市中，作为人口密度最高的城市之一的新加坡高居第二，拥有29.3%的城市冠层覆盖。其次，在Timothy Beatley 2016年出版的《自然城市规划与设计手册》一书中的第二部分，有一章专门撰写了新加坡，主题是“创建自然城市：新兴全球实践”。

通过实施NCMP，国家公园局使生物多样性保护融入城市发展历程，从而将新加坡发展成一个宜居和可持续的亲生态城市，一个人类和城市生物圈的模范城市②。

注释：

① 公民科学家是指非学术或职业的科学家、科学爱好者和志愿者。这些公众自动自发共同参与科研活动，收集数据并检测生物多样性的变化，致力于加强科学研究的普及化。

② 有关国家公园局生物多样性保护工作的更多信息，请参阅：城市生物多样性：https://www.youtube.com/watch?v=7TlA-wSEwWQ；城市中的公园：https://www.youtube.com/watch?v=jLRROkGGBfM；新加坡亲生态城市：国家公园局关于生物多样性保护工作的原始视频：https://www.youtube.com/watch?v=XMWOu9xIM_k。

图表来源：

图1～16©NParks；表1根据参考文献[3]的605页修改。

（编辑/刘玉霞）

Singapore has established a reputation over the years as a successful，first-world “City In A Garden”，where urban infrastructure is integrated into a matrix of greenery.Through a combination of political will and foresight，supported by dedicated and highlytrained technical agencies，Singapore has enjoyed a half-century of practical experience in realising a green cityscape (Fig.1).

In the past decade，there has been a shift in the focus of how cities and their human populations can interact with，and benefit from the natural ecosystems around and within them.City planners have become interested in promoting“biophilic urbanism” and “biophilic design” to illustrate how urban landscapes should integrate greenery and biodiversity into infrastructure.This emergent trend has been led by Singapore，which was in the forefront of evolving our urban greenery strategies to look beyond simple amenity planting，to science-based strategies to conserve natural ecosystems as well as harmoniously support biodiversity in a highly urbanised island city-state.

1 Background

When Sir Stamford Raffles landed in Singapore in 1819，most of Singapore was covered by pristine primary lowland dipterocarp forest，freshwater swamps，mangrove forests，etc.

Contrary to popular belief，the clearance of Singapore's original forests did not come with the advent of modern-day urban development，but rather，with 19th-century agriculture.Due to rapid and intensive agricultural development，more than 90% of the Singapore's natural forests had already been cleared by 1930[1].When Singapore gained independence in 1965，it inherited an island depleted of much of its original forest cover，and only fragments of natural ecosystems were left.How did Singapore in a span of 50 years of independence manage to convert an impoverished landscape to one that the MIT Senseable City Lab's Treepedia rated as one of the cities with the highest Green View Index in spite of its high population density?

9 东方斑犀鸟现在可以在新加坡的许多城市地区看到Anthracoceros albirostris can now be seen in many urban areas around Singapore

10 在主要水道和沿海栖息地中经常遇到滑毛江獭Lutrogale perspicillata is commonly encountered in major waterways and coastal habitats

11 新加坡特有极度濒危的新加坡淡水蟹在人工繁殖技术下成功繁殖Johora singaporensis,a critically endangered endemic freshwater crab,with newly-hatched young in captivity

2 Modern Singapore—from Garden City to a Biophilic City in a Garden

“We have built,we have progressed.But there is no hallmark of success more distinctive and more meaningful than achieving our position as the cleanest and greenest city in South Asia”

Extract from Mr Lee Kuan Yew's speech at the launch of Singapore's first Keep Singapore Clean Campaign - 1 Oct.1968

Singapore launched its tree-planting campaign on 16 June 1963 when founding Prime Minister，the late Mr Lee Kuan Yew，planted a Mempat tree，Cratoxylum formosum.This historic event marked Singapore's first step in the green journey towards a Garden City.At the highest political level，there was a strong vision and clearly-articulated directive that Singapore should be a Clean and “Green Garden City”，and an oasis in what was then a Third-World backwater.Lee Kuan Yew believed that greenery and cleanliness not only served as a visible statement of Singapore's efficiency and good governance，but that greenery should be made accessible to all levels of the community rather than just the well-to-do.Taking the greening of Singapore to a higher level，NParks evolved its vision to making Singapore a City in a Garden.

Twenty-first century Singapore's approach to greening and nature conservation is founded on a science-based approach to understanding and benefiting from greenery and biodiversity.Singapore acknowledges the fact that its various ecosystems and habitats，and all its species are an inseparable part of the island's rich and ancient natural heritage.Singapore has also taken the cue from recent studies indicating that the benefits of a green and biodiverse city - such as resilience to and mitigation of extreme weather events like drought and flooding; reduction of airborne pollutants; and improvement in the physical and mental wellbeing of its citizenry- contribute to a resilient，sustainable and liveable nation.

With this in mind，Singapore has built an impressive green matrix in a first-world economy- a “Biophilic City In A Garden”.Singapore is an island city-state with a terrestrial area of around 719 square kilometres.Despite being highly urbanised，Singapore still harbours a wide range of native biodiversity，including around 2，215 plant species(ever recorded)，61 mammal species，403 bird species，334 butterfly species，131 dragonfly species，more than 800 spider species[2]583-609.Its marine biodiversity，including，12 seagrass species，255 hard coral species，and more than 200 sponge species，is equally rich (Tab.1)[3].What is more surprising is that new species discovery and re-discovery of species previously thought to be extinct are still occurring，as evident from the over 480 new species of animals and plants recorded over the past five years[4].

The future goal is not just ensuring that Singapore's rich native biodiversity thrives in a land-constrained，densely built-up landscape，but to create an “urban ecosystem” where infrastructure and human activities are synergised with the ecosystem services and other benefits provided by greenery and biodiversity.The solution has to be based on a multidisciplinary，inter-sectoral and comprehensive approach，with an inclusive participation by all stakeholders，and supported by strong scientific research.

12 新加坡卫星地图上绘制的生态网络和连通性指数An ecological network and connectivity index plotted over a satellite map of Singapore

13 Marsdenia maingayi（左，牛奶菜属的一种）和Renanthera elongata（右，火焰兰属的一种），最近都在中央集水区自然保护区重新发现Marsdenia maingayi (left) and Renanthera elongata (right),both recently rediscovered in the Central Catchment Nature Reserve

14 夜视设备，如红外相机（左）和热成像仪（右），对于研究许多夜间脊椎动物的种群和习性大有裨益Night vision equipments such as infrared camera (left) and thermal imaging equipment(right),have resulted in highly successful research into the population and ecology of many nocturnal vertebrate species

3 The Nature Conservation Masterplan

Guided by science-based principles，the Nature Conservation Masterplan (NCMP) consolidates，coordinates，strengthens and intensifies Singapore's biodiversity conservation efforts[5].These efforts will build ecological resilience through the strengthening of ecological linkages that will help us conserve our native biodiversity and also adapt to the effects of climate change.

The NCMP consists of four thrusts:firstly，the conservation of key habitats; secondly，habitat enhancement，restoration，and species recovery; thirdly，robust and credible research in conservation biology and planning; and fourthly，community stewardship and outreach in nature.All our conservation initiatives encompass terrestrial，coastal and marine ecosystems，at the ecosystem，species and genetic levels.

3.1 Conserving Our Key Habitats

The key objectives of the first thrust are to safeguard and strengthen the core biodiversity areas; secure and enhance buffer areas; enhance and manage additional nodes of greenery throughout Singapore; develop ecological connections; and integrate nature with the broader urban landscape.

The core biodiversity-rich areas comprising 1) Bukit Timah Nature Reserve (Fig.2-1)，2) Central Catchment Nature Reserve (Fig.2-2)，3) Sungei Buloh Wetland Reserve (Fig.2-3)，4) Labrador Nature Reserve (Fig.2-4)，and 5) Nature Areas including Pulau Ubin and Sisters' Islands Marine Park，harbour the majority of Singapore's native biodiversity and are the key gene pool repositories and sources.Diverse ecosystems，including lowland dipterocarp forests，secondary forests，freshwater swamps，streams and rivers，grasslands，mangroves，rocky shores，sandy shores，inter-tidal mudflats，sea grass meadows，coral reefs，open waters，etc.，are represented in these core areas.As an illustration of the compactness of Singapore，all these areas lie within a forty-minute drive from Changi International Airport.Without a natural hinterland，Singapore is one of the few nations on earth where its core nature reserves are located within the city.

To buffer these important core areas from edge effects like drying conditions，strong winds，and penetration by invasive alien species，areas adjacent to core areas are designated as nature parks.For example，the Central Catchment Nature Reserve is surrounded by Chestnut Nature Park，Zhenghua Nature Park，Springleaf Nature Park，Thomson Nature Park，Windsor Nature Park，Dairy Farm Nature Park，Hindhede Nature Park，Rifle Range Nature Park，etc.(Fig.3).Similarly，the extension of Sungei Buloh Wetland Reserve to include Kranji Marshes and the Mandai Mangrove and Mudflat contributes to the critical mass required for effective biodiversity conservation.

Many rare and critically endangered species have been found beyond the core areas.To more comprehensively conserve these species，special attention has been placed on enhancing the integrity of additional nodes of greenery.

To counter fragmentation of natural habitats，the buffer parks mentioned above，as well as a network of ecological connectors work together as key elements of a strategy to expand the ecological space available to native flora and fauna.Buffer parks add to the ecological footprint of core nature reserves and ecological connections provide an island-wide matrix for native fauna to forage and breed，and native flora to disperse to.It is based on this principle that we have identified potential ecological connections linking core areas using geographical information systems (GIS)，modelling techniques to track pathways of least resistance，etc.Park connectors spanning 313 km，80 km of Nature Ways[6]，the Eco-Link@BKE (Fig.4)，and intensified multi-layering planting of roads with native plant species (Fig.5)，are some of the initiatives implemented to extend ecological connectivity throughout Singapore.Additionally，skyrise greenery projects function as stepping-stones for birds，butterflies，dragonflies，and other flying animals.

To accord due attention to Singapore's rich marine biodiversity，we have prepared a Marine Conservation Action Plan (MCAP).One of the initiatives highlighted in the MCAP was the establishment of the Sisters' Islands Marine Park(SIMP,Fig.6) which is situated in the midst of the well-plied fairways of one of the busiest ports in the world.The results of agent-based modelling research support the location of the SIMP as it serves as a potentially effective source reef for marine organisms whose gametes or larvae can be distributed across all coastal and marine areas in Singapore.The objectives of SIMP are to promote conservation，research，and education and outreach.An in situ hard coral repository is currently being established at SIMP，targeting to harbour all native extant hard coral species found in Singapore，which amounts to over 30% of the global total of over 800 hard coral species.

NParks has also developed an Integrated Urban Coastal Management (IUCM) Programme that promotes coordinated activities in the coastal region[7].This model has been shared in regional fora such as the Partnership on Environmental Management in the Seas of East Asia (PEMSEA)，etc.It will be increasingly relevant as more coastal cities expand their urbanisation.

3.2 Enhancing and Restoring Habitats and Assisting in Species Recovery

It is inevitable that natural landscapes in cities degrade over the years due to human activities and land use changes.With increasing evidence that biodiversity provides ecosystems that are beneficial to human health and well-being，it is essential that the functional integrity of natural sites be repaired through habitat restoration，enhancement and creation efforts.Hence，the second thrust of the NCMP focusses on a) habitat enhancement and restoration in core areas，buffers，other greenery nodes and ecological connections，and b) species recovery.

Habitat enhancement techniques，besides being implemented in natural areas，are also applied to urban landscapes or biodiversity-impoverished sites.A trail planted with butterfly-attracting plants spans a stretch of Orchard Road，which is one of the busiest shopping areas in Singapore.A freshwater wetland habitat，known as the Keppel Discoverl Wetlands，was restored in the SBG Learning Forest (Fig.7) which lies in the buffer zone of the Singapore Botanic Gardens，a UNESCO-inscribed World Heritage Site.It restores the hydrological process，regenerates the lowland rainforest，brings people closer to nature and serves as a refuge for threatened freshwater flora and fauna[8].

In January 2019，the National Parks Board unveiled the Forest Restoration Action Plan，which seeks to strengthen the resilience of our native rainforests by restoring ecological processes and enhancing biodiversity and ecological connectivity.The Action Plan also aims to assist the succession of early secondary forests to more mature and diverse rainforests over time，thereby improving habitats for biodiversity.The approach will comprise the planting of a framework of native plant species that fix nitrogen to naturally improve soil conditions and would also attract pollinators and dispersers.Removal of weed species will also be undertaken to assist regrowth.Dominant primary rainforest species will also be introduced.

In a small island like Singapore where species diversity is high，most of the populations of Singapore's flora and fauna，in particular，endemic species，will inevitably be endangered，threatened or rare.These species have been given extra assistance to ensure that their populations reach sustainable levels.For example，the largest orchid in the world is the Tiger Orchid，Grammatophyllum speciosum (Fig.8)，once thought to be extinct in Singapore.With the propagation in nurseries and widespread planting of this orchid all over the island，the conservation status of the Tiger Orchid has greatly improved in Singapore.These orchids never fail to delight when they bloom in the parks，gardens and along the roads.Similarly，the Singapore Kopsia，Kopsia singapurensis，is a species found only in the wild in freshwater swamp forest habitats of Peninsula Malaysia and Singapore and is critically endangered locally.An ex-situ conservation project for the species is in place，with cuttings being cultivated in the Singapore Botanic Gardens and the Pasir Panjang Nursery and being planted out in forest enhancement and restoration projects，such as the rewilding of the Rail Corridor.

15 采集水样用于各种水生或海洋生物的eDNA监测Samples of water are taken for eDNA monitoring for a wide range of aquatic or marine organisms

An avian species once thought to be extinct in Singapore is the Oriental Pied Hornbill，Anthracoceros albirostris (Fig.9).A few hornbills flew into Pulau Ubin to nest around 1997.Research indicated that the limiting factor was the lack of suitable nesting sites.With the erection of smart nest boxes in tall trees in several different locations，the hornbill population has now increased to more than 100 hornbills.

Another charismatic species that has made a comeback in Singapore is the smooth-coated otter，Lutrogale perspicillata (Fig.10).Once thought extinct in Singapore，the otter made a reappearance in the mid-1990s.The enhancement of coastal habitats as well as municipal waterways (such as the Bishan-Ang Mo Kio Park and Marina Bay) has resulted in the resurgence of the species.Today，the population of smooth-coated otters stand at more than 70 individuals.There is a collective，multidisciplinary approach towards otter conservation in Singapore，with the involvement of NParks and the Otter Working Group，which tracks the otter populations and movement islandwide.

Our current species recovery programmes include the endemic crab，Johora singaporensis，the endemic Cryptocoryne × timahensis，etc.To assist the long-term survival of the Johora singaporensis(Fig.11) which is listed by the International Union for the Conservation of Nature and Natural Resources as one of the 100 most endangered species，NParks is carrying out ex situ breeding，translocating individuals to other suitable freshwater streams and researching on the ecological requirements of this endemic crab.To-date，more than 300 individuals of this crab has been successfully brooded in NParks' facility.

16 公民科学家①参与生物多样性调查Citizen scientists① participate in biodiversity surveys

Of particular note is the rediscovery of the iconic Neptune's Cup sponge，Cliona patera，in its type locality of Singapore.It was once assumed extinct for close to a century until an individual was dredged up off the coast of Australia in 1990.The rediscovery of the first 2 live individual specimens in 2011 and the subsequent discovery of another 3 individuals make Singapore the only place in the world currently with known specimens of the sponge in the wild.More than five individual Neptune's Cup sponges have been translocated to optimum sites off the Sisters Island Marine Park，and their growth and health constantly monitored.

3.3 Applied Research in Conservation Biology and Planning

The third thrust comprises diverse initiatives such as a) comprehensive surveys[2]3-17,[9-11]and long-term monitoring of ecosystems and species;b) quantitative ecological research; and c) sciencebased policy formulation and management planning.A key strength of NParks research and operations work is the constant application of up-todate technology，including geographical information systems，agent-based modelling，numerical modelling，genomics，3D modelling，and LIDAR，amongst others.Conservation and biodiversity research in Singapore takes place at a hierarchy of levels - at the whole-ofcountry level; landscape level; ground level; and down to the microscopic and genetic level.

At the whole-of-country level，satellite imagery is a very powerful tool for a diverse range of research projects undertaken by NParks.From establishing the veracity of Singapore's total green cover，to identifying green corridors for connectivity research，and even to spectral analysis of satellite images to detect unhealthy patches of forest - NParks has leveraged on this technology as a planning and decision support tool (Fig.12).

At the landscape level，another suite of hightechnology tools is being applied in areas as diverse as planning，conservation，and arboriculture.LiDAR models of entire streetscapes allow for estimation of the growth rates of tree crowns and the determination of appropriate pruning measures.Agent-based modelling of the movements of coastal flora and fauna，including shorebirds，coral larvae and mangrove propagules，allow for the conservation of critical habitats that serve as either feeding sites or sources of recruitment.Drone technology has also become an important technological tool in greenery research and operations.Aerial drones provide low-cost solutions to help track the growth of habitat enhancement and reforestation sites over time; survey tree canopies for orchids and other epiphytic plants of interest; and even survey trees for defects.

At the ground level，biodiversity surveys remain a key component of conservation research.Recent surveys of both terrestrial and marine ecosystems have resulted in the discovery of at least 3 new endemic plant species，i.e.，Zingiber singapurense，Hanguana rubinea and Hanguana triangulata，more than 150 species of the Dolicopodidae longlegged flies，and over 100 new marine organisms.By ensuring that there are sufficient marine habitats outside of the maritime fairways and that mitigation measures are put in place when development projects are carried out in the marine environment，we have maintained marine biodiversity richness in Singapore despite being one of the world's busiest ports.The continued finding of new species indicates that we have yet to reach the plateau of the new species discovery curve.It is also heartening that many plant species that were previously thought to be extinct，i.e.，where sightings had not been recorded for over 50 years，have been re-discovered as a result of systematic and intensified field surveys(Fig.13).

Technological advances have also changed the game for biodiversity surveys.In particular，the use of camera traps and night vision equipment has allowed for highly successful nocturnal studies of forest vertebrates，of which a majority are active only at night (Fig.14).The next innovation in survey methodology involves the use of acoustic sensors，either on land or in the marine environment，to monitor either the vocalisations of faunal species，or in combination with sonar devices，determine the species and individual numbers of coastal and marine species such as dolphins，whales and even crocodiles.

Having obtained a good knowledge of the species found in Singapore，we are undertaking quantitative studies and ecological research on the intricate inter-relationships among species.The analyses of the results of these complex linkages with up-to-date predictive modelling tools will enable us design better management plans and facilitate science-based decision-making.

At the molecular and genetic level，DNA analysis is now coming to the fore as a means to further examine the relationships between flora and fauna species in Singapore and the rest of the region;as well as an advanced survey method.Genetic research has been conducted on the population of Raffles banded langurs in Singapore to better understand the genetic viability of the species.Environmental or “eDNA” studies are now being conducted with a view to deploying the technology to monitor Singapore's waters for a wide suite of marine organisms，including possible alien invasive species(Fig.15).

3.4 Community Stewardship and Outreach in Nature

The last prong of the NCMP seeks to involve the entire community for inclusiveness through the Community in Nature (CIN) programme.CIN is a national movement launched in September 2011 to connect and engage different groups in the community，including a) families，b) passionate individuals，c) educational and research institutions，d) corporations and companies，e) non-governmental organisations，and f) government agencies，to act as stewards of Singapore's natural heritage.

Some of CIN's initiatives include:a)incorporation of biodiversity into all levels of the education system，b) a strong Citizen Science programme where the public，schools，scientists and amateur naturalists partake in annual “bioblitzes”;bird watch; butterfly watch; heron watch; and dragonfly watch events (Fig.16)，c) Greening of Schools for Biodiversity which provides hands-on experience for students to carry out biodiversity surveys，document biodiversity，and enhance habitats around their school environs，d) maintaining a biodiversity database and atlas for Singapore and allowing members of the public to easily contribute to biodiversity sightings through the use of a mobile application，“SGBioAtlas”，and e) organizing an annual celebration of biodiversity known as the Festival of Biodiversity (FOB)，in order to spread knowledge about Singapore's natural heritage and biodiversity to the heartland community.

NParks organised activities from 18 May to 26 May 2019，culminating in the FOB.More than 3，300 participants took part in the nation-wide“bioblitz”，covering more than 90 sites，including our marine park.

There are also numerous community-based platforms for the public to involve themselves in greening and biodiversity conservation，including Community in Bloom，Friends of Ubin Network(FUN)，Pesta Ubin，and Friends of the Parks.Together，these various programmes and platforms allow for a broad and deep engagement with Singaporeans across all demographic groups.NParks also encourages active participation in projects and even the employees of corporate sponsors participate as hands-on volunteers in the projects they fund.

4 Monitoring Success—Singapore Index on Cities’ Biodiversity

NParks is the national focal point for the United Nations Convention on Biological Diversity(CBD).In order to track our own success in greening and biodiversity conservation and to support other cities in establishing a common set of indicators for success，we have worked with the secretariat of the CBD in collaboration with the Global Partnership on Sub-National Governments and Cities for Biodiversity on the development of the City Biodiversity Index.Also known as the Singapore Index on Cities' Biodiversity (SI)，this is a self-assessment tool for the evaluation of biodiversity efforts carried out by cities[12].Twentyfive cities worldwide have applied the SI and around 40 cities are in various stages of applying the SI.

5 Resional and International Committments

NParks is also a member of the Singapore delegation to the meetings of the United Nations Framework Convention on Climate Change.Our dedication to cultural heritage is reflected by the inscription of the Singapore Botanic Gardens as Singapore's first World Heritage Site on 4 July 2015 during the 39th session of the World Heritage Committee in Bonn，Germany.In recognition of its significant contributions to biodiversity conservation in Singapore，NParks was named the laureate of the 2017 UNESCO Sultan Qaboos Prize for Environmental Preservation.

Sungei Buloh Wetland Reserve and Bukit Timah Nature Reserve，both managed by NParks，have been designated as ASEAN Heritage Parks.

6 Conclusion

Comprehensive surveys and long-term monitoring reveal that Singapore is endowed with rich native biodiversity.Conserving our Nature Reserves and nature areas，along with the way we manage our parks，Park Connector Network，and streetscape，have secured suitable habitats for native biodiversity to thrive in Singapore.Additionally，by reaching up to the skies with skyrise greenery and vertical green walls，and extending our conservation efforts to the coastal and marine environments，we have added multiple dimensions to the understanding and practice of a biophilic city.

This concurs with the independent assessment by two external parties.Firstly，the Treepedia measures the canopy cover in cities in the form of a Green View index (GVI).Of the first 27 cities that they have analysed，Singapore is second with 29.3% despite being one of the cities with the highest population density.Secondly，Timothy Beatley in his book published in 2016，“Handbook of Biophilic City Planning and Design” devoted one chapter on Singapore in part 2 of the book focussing on “Creating Biophilic Cities:Emerging Global Practice.”

By implementing the NCMP，we have embodied biodiversity conservation as part of the development process，hence，evolving Singapore into a liveable and sustainable biophilic city②.

Notes:

① Citizen Scientists are “Members of the public who are neither academics nor government researchers who participate in scientific research and monitoring and whose outcomes contribute to advancements in scientific knowledge as well as enhancing the public's understanding of science”.

② For more information on the biodiversity conservation efforts for NParks,please refer to:Biodiversity in the City:https://www.youtube.com/watch?v=7TlA-wSEwWQ; City in a Garden:https://www.youtube.com/watch?v=jLRROkGGBfM;Singapore Biophilic City:Original length:https://www.youtube.com/watch?v=XMWOu9xIM_k.

Sources of Figures and Table:

Fig.1～16©NParks; Tab.1 is modified from a table on page 605 of Reference[3].