健康的生态系统服务和人居环境：泰国北部的机遇与挑战

著：（泰）彭瑟刚·萨布卡特派桑 （泰）维帕微·素琳桑 （泰）朱拉叻·瓦尼查雅派实 （泰）艾格猜·亚批蒙 译：徐琴

0 前言

1 清迈省的人口密度和增长率[15]Population density and growth in Chiang Mai province[15]

越来越多的迹象表明人居环境的可持续发展对于人类健康至关重要。人类从很多方面得益于健康的生态系统，包括食物供给、洁净的空气和水、温度调节以及大自然均衡的授粉[1-2]。不仅如此，也有证据显示健康的生态系统对于我们的健康有更直接的益处，可使我们免遭身体和心理上的疾病，提高我们的运动能力[3-4]。因此，设计师、规划师和学者们应当为了形成健康的生态系统服务而共同创建人居环境，这同时也能对人类身心健康产生积极作用。数个包括全球健康倡议（Planetary Health Initiative）在内的国际组织也都意识到这一事实，并认可为了健康生态系统而做的良好规划能提升我们应对环境变化的适应性，在缓解恶劣环境条件的同时促进人类健康[5]。

尽管景观和城市规划领域为创建健康的人居环境提供了相当多的支持，仍然有许多城市在改善的过程中面临很多挑战和机遇[6-7]。目前的环境设计和健康理论仍在发展当中，并需要更多有效的设计实践来填补相关研究空白[4]。文化和物质环境决定了设计师如何应用理论以及设计决策的有效程度。当多方合作欠缺明确方向性时，容易增加健康人居环境在建设过程中失败或延误的风险[8]。审慎的规划和设计要求所有的利益相关者参与到合作过程当中[9]，不同的解决方案都应始于针对现存环境中的已知问题。

泰国北部可被视作是机遇与挑战相交汇的典型案例之一。自从被清迈中部的Lanna帝国占领之后，该地区便加强了与中国南部、缅甸和老挝的文化联系[10]。该地区在地理上由山脊、河谷以及扇形平原组成，遍布上游源头的丛林和肥沃的土壤，也是许多山地部落和城市的发源地[11]。作为一个拥有悠久历史、多样性和自然资源的地区，泰国北部亦是研究生态系统和人居环境关系的绝佳案例。

笔者就泰国北部环境与人类健康相关的3个议题进行讨论，旨在提出设计师和学者们相互合作的方式，以期实现景观与城市规划协同共建健康的生态系统和人居环境。本研究的视角可为填补设计和规划实施中的理论研究空白提供一些启示，并为景观和城市规划领域的持续发展指明方向。

1 可居住的城市和环境公平

建成环境对于人类的身心健康具有直接作用，城市环境尤其如此。清迈市几世纪以来都按照古代的规划准则而设计[10,12]，近年来由旅游扩张、人口增加和新的技术要求所引起的变化正在影响着城市的可居住性。虽然城市在持续繁荣发展，然而部分居民可能被忽视了[13]。类似的故事正在全世界的不同城市发生着，只有解决了这样的问题，我们才能不断建造所有人类和生态系统都能健康共存的城市。

清迈是一个城市和自然元素能达到独特平衡的世界知名旅游目的地。城市护城河以内的区域被用作综合开发，并拥有大量树木。因此，许多人慕名前来居住、投资和观光，这些投资者、新进居民和游客给城市带来经济上的繁荣。然而，超过城市容纳能力的过度开发将威胁城市居民的健康生活，也将降低城市的历史价值。2006—2016年，仅近期搬来清迈的投资者，就使城市的经济呈现了几何级数的增长。截至2016年，清迈每年迎来近900万人次的游客[14]。随着城市人口的持续增长，清迈变得越来越拥挤，其中Mueang区每平方千米的人口就达到了1 541人[15]（图1）。持续的增长导致了商业区、摊贩和交通需求的增加。由于城市从未发生过如此迅速的扩张，不管是公共交通、人行道、基础设施，还是绿地都变得拥挤和过度使用。当规划师未对所发生的事件进行事先部署时，城市就将难以满足其居民的需求，从而影响到市民的健康生活。

清迈倘若借鉴世界上其他模范城市的经验，仍有望在此基础上有所改观。新加坡在1967年由时任首相李光耀介绍为“绿地率最高的城市”。新加坡的规划旨在通过大量绿地和整洁的环境来改善市民的生活质量和吸引游客。在这之后，新加坡进一步将该理念发展为“花园城市”的设想，把绿色空间融入每个人的日常生活中[16-17]。与新加坡的情况相比，清迈拥有更多空间来发展公共绿地。清迈的规划师和风景园林师们应为了市民的健康生活而考虑保护和改善这些绿地。

即使是在拥有美丽公园和街道的城市，也不是所有本地居民和游客都能同样地使用这些绿色基础设施。平等的概念要求城市为每一个人提供健康生活的机会，其中每一位居民都能在需要时享用到所需设施[13]。在最近清迈大学农业系和香港大学的合作项目中，学生们调查了清迈市护城河周边区域的居住地，试图了解其中各个阶级人们的变化、运动轨迹和不可见性。结果发现清迈护城河拥有很多面，并不是每一个人都能得益于护城河所带来的好处，进行散步、骑车和使用绿地。

有限的绿地可达性和户外散步机会可通过多种途径影响人的身心健康。首先，人们需要通过一定的体力活动来维持健康。日常散步和慢跑能有效避免心血管疾病和病理性肥胖[18-20]。其次，与自然的接触帮助减小压力和提升注意力[4]，因此使用公共绿地可以有效改善每个人的身心健康状况。现如今，世界各地的许多居民都由于各自城市设计的原因，拥有越来越少的户外空间使用机会。在大部分城市中，阻碍环境设计实现社会公平性的因素有如下3点。

1）步行可达性。在许多大型城市中，步行通道常常被限制或干扰。这不仅减少了行人的步行舒适度，也剥夺了轮椅使用者的选择[20]。在向行道树和车行道让步的同时，步行可达性往往被忽视或者只考虑最低限度。

2）公共交通。虽然步行环境对于街区来说很重要，设计良好的公共交通系统也有助于提升户外活动，使居民更易到达公共绿地[21]。同时也能减少私人交通工具和汽油的使用，有利于生态环境。

3）安全感。如果某处空间让人感到不安全，即使是有阴凉的步行道和公共绿地可供选择，人们也不会使用，因此也不会从中获得身体和心理上的益处[22-23]。空间的安全感可以通过植被设计、建造材料的选择和维护来营造[24-25]。

为了解决以上这些问题，清迈的规划设计师在做决策时应考虑居住和步行环境，以提高居民健康和福祉。只有当城市变得更适宜居住，游客才会不断到访，维持城市的收入和经济增长。针对户外绿色空间可达性所做的周密规划能帮助提升城市的可持续性及环境公平，也只有这样才能促成更加健康的人居环境。

2 城市景观、农业景观及食物基础设施

不同社会阶层的人们都需要食物。对食物的获取是人类生活最重要的环节之一。解决全世界的饥荒也被最新“可持续发展目标”（Sustainable Development Goals, SDGs）列为首要目标[26]。不仅如此，食物也是文化和经济的体现。从原材料收割、烹饪方式到多种多样的饮食习惯，都涉及大量的本土知识；反过来说，利用食物所创造的不同味道、元素和口感对于食物本身来说也是独一无二的。纵观历史，国际贸易、全球运输、城市化和科技的盛行共同造成了食物全球化。食物全球化使我们体验到了前所未有的丰富多样的食物，同时也极大地影响了人类与食物的互动方式。食用和烹饪行为的改变通过多种途径影响着本地食品系统，包括食物多样性、生产、消费、贸易、品质和人们摄入的营养元素[27]，这些改变都间接影响着人类的身心健康，例如长时间食用相同的食物易导致肥胖与营养不良[28-29]。

食物全球化与快速的城市化共同作用于健康的生态系统。随着现有的农业用地被逐渐转化为城市用地，农学家们不得不选择忽略生态系统的重要性，转而开发天然土地来种植更多粮食，以满足日渐增长的食物需求[27]。

对食物的高需求也导致了大规模单一农作物的生产。单一作物的栽培促进其商品化和出口。尽管这在经济上与食物全球化的趋势并不矛盾，却减少了食物多样性并替代了本土美食文化[30]。这一现象会导致单调的饮食习惯，为了确保产品数量而使用的化学物质也因此越积越多。其中的一些农药残留容易引起食物中毒或者诸如癌症、神经损伤、激素和免疫类疾病以及新生儿健康问题等长期的健康隐患[31]。另一方面，源自不同文化的农耕方式原本应关注的是生存、季节性和对原始食材的使用，并以此在各地之间相互交易[32-33]。

维持食物全球化带来的益处并降低成本的方法之一是构建本土食物基础设施。最基本的基础设施网络能满足市民们的生活所需并使他们享受到政府服务。通常来说，基础设施一般指道路、高速公路、公共交通、电力网络和市政用水等城市交通系统和公共设施[34]。然而，城市同时也应考虑如何将食物资源纳入城市整体环境当中。土地使用性质，尤其是农业用地，正在随着快速的全球化进程而改变[35]。农业用地一直以来都为人口提供所需食物。在较古老的城市模型中，每个城镇都能够自给自足，但随着人口密度的增加和农田的减少，大部分城市由于时间、空间、工具、仓储和生活方式的限制不再能提供足够的食物。因此，大家不得不从其他地方购买原料和加工食品。虽然这样的生活方式在短期内显得实用，但当所有人口的食物都依赖于从外地运输而来时，这样的系统将会极度脆弱[27,36]。

往前看，风景园林师和城市规划师所构建的建成环境必须考虑规划和发展本地的粮食供应。这意味着充分考虑了潜在食物生产机会的土地使用规划，将会使城市和农村的居民们获取更加健康和多样的食物，同时也生活在一个更健康的生态系统中。这样的土地规划需要应用到土地使用管理中的“景观基础设施”概念，指景观需要为人类提供必要的基础设施，尤其是食物[37]。

食物基础设施通过支持绿色空间网络和城市的发展，为生活在市区、郊区和农村地区的人们提供了更多选择[32,38]。也在农村地区的个体和社区层面上，进一步开发了生产地方特产的潜力，这要求我们更多地了解农村和自然地区的诸如野生草本植物这类更具地方性的食物种类。

清迈及泰国北部，与很多其他地方一样，都具有构建独特食物基础设施的潜力。Anderson[39]记录了泰国北部山地部落使用的超过1 000种植物种类[40]。Jacquat[41]的研究显示了在泰国本地集市中发现的241种植物，包括观赏植物、姜类、蘑菇类、棕榈植物和竹类。最新的一项研究在泰国北部的居住区花园中发现了丰富的树种资源，其中有能证实食品安全和效益的可食用叶子及果实等[42]。虽然类似的食用植物多样性可能存在于泰国北部或世界上任何地方，现有的这些研究并未讨论将理论与城市发展相结合并解决粮食短缺的可能性，而聚焦在本土粮食供应。

在最近的疫情背景下，城市地区的粮食供应问题变得格外严峻。随着国际贸易的中断，城市居民依然需要依赖于其他地方的食品生产。进一步完善和发展食品生产行业，帮助城市中较低阶层的人们在今后遇到类似的情况时幸存下来。

食物基础设施在不同环境下具有多种形式。泰国乡村的居住区花园便是家庭食物来源的典型例子。大部分农村地区居住区花园种植的都是可食用植物。Lattirasuvan曾就泰国北部Phrae省的一处居住区花园进行调研，发现其中包含了草本、药用植物、水果和淀粉类植物[43]（表1）。Yaipimol在社区尺度上研究了泰国东北部的一处社区食物来源，结果表明社区森林和水源森林是农村食物基础设施的重要组成部分，为其提供绿叶蔬菜、鱼和贝壳类[44]。

表1 根据植物种类和用途分类的居住区花园植被数量[43]Tab. 1 Numbers of plants in residential garden by types of plants and uses[43]

在城市层面上，行道树、开放空间、寺庙、学校和政府办公地等公共机构都能提供农业生产。曼谷Laksi行政区办公楼的屋顶花园允许工作人员种植蔬菜并将种子带回家里[45]。社区花园和寺庙花园也为较低收入阶层的人群提供了更多食物选择和融入文化的机会。

设计食物基础设施的方式有多种，只有意识到食物生产的重要性才能引导食物基础设施更好地发展。风景园林师和城市规划师必须考虑所创建的食物基础设施要能为我们提供具地方性和多样性的食物。这样的发展过程与建设任何一项好的基础设施一样，需要审视所有可行的政策、规划和设计。这一理念对于城市食品安全至关重要。一方面，在为城市人口提供更多可获取的食物选择时，也改善了城市生态系统[46]。另一方面，也促进了城市的可持续发展，为居民和游客提供多元的文化体验，为建成环境中的每一员提升生态系统服务[47]。

3 森林景观、空气污染和用水安全

尽管大部分人类聚居地位于城市和郊区范围内，人类和森林的关系仍然极大地影响着生态系统和人类健康。泰国北部的森林对人类的身心健康以及境内的动物而言非常重要。森林的生态系统服务提供了丰富多样的食物资源、药用植物以及用于搭建住处和能源的木材[48-49]。不仅如此，泰国森林还缓解洪水和山地滑坡对下游居住地的侵袭[50]。水源林为从山地部落到泰国中部沿海城市的每一个人提供必要的洁净用水[51]。多种多样的森林帮助调节湿度、回收碳元素和传播颗粒物质[52]。因此，除了它们的固有价值以外，泰国北部的森林对于整个国家的健康状况都有直接联系。

然而，泰国的森林正处在危险当中。泰国北部地区常见的山地生态系统在险峻的陡坡、全球气候变化和人类聚居活动面前显得格外脆弱[53]。尽管近几年的森林砍伐现象有所好转[53]，曾经消失的林地仍然对地区内的生态健康留下深远影响。设计师和规划师们必须共同努力，以期将森林恢复到原始状态。

泰国北部森林同时也影响着清迈和周边地区的空气污染问题[54]。在雾霾季节，清迈的PM2.5值达到全世界最高[55]。PM2.5指直径小于2.5 nm的微粒，虽然清迈直到最近几年才开始测量空气中的PM2.5值，其关于空气污染问题的记录却始于1987年，且在近几年迅速恶化[8,56]。居高不下的PM2.5值导致泰国北部数百万人受到呼吸和血液循环系统疾病的困扰[54]，尤其是孕妇、老人和小孩等弱势人群。短期暴露于这些颗粒物质会引发咳嗽和喘息，长期则会导致哮喘和肺癌，甚至死亡[7,57]。PM2.5问题的一个重要起因便是森林火灾。泰国北部的森林火灾非常普遍并具有季节性[53]。另一个逐渐受到关注的原因来自于人类与环境的互动。自然和人为的气候变化致使旱季更加干燥，火焰尤为猛烈[58]。森林管理也影响着火势的强度和蔓延[59]。当地居民和山地部落族民们烧火狩猎、采集蘑菇和耕作的行为也加剧了PM2.5的形成。当这些行为局限于较小范围时，他们属于人类生态的一部分，对环境的影响微不足道[59-60]。然而对农产品不断增长的需求使得森林火灾所致的空气污染越发严峻，大面积的森林砍伐使情况进一步恶化[59]。

森林砍伐带来的另一个问题是水资源缺乏。人类的健康生活取决于对洁净水源的获取。泰国北部的森林砍伐阻碍了泰国下游地区得到足够的水资源。洁净的饮用水帮助我们调节体温和维持身体功能。农民也需要水才能生产食物[61]。如果缺少最重要的水源，大部分人都将面临经济和健康威胁。泰国曾经在减少森林砍伐和农业不法行为方面取得不少进展。大量人类聚居地都从水源高地迁移到了生态性较坚韧的低地。并采取了一些农业措施缓解森林砍伐[60]。然而，许多更为敏感的问题仍未解决，例如地处水源森林的聚居地对工、农业的投入以及过度饱和的旅游业[59]。这些问题都亟须从各方面被重新审视，最终的解决方案也应立足于改善所有利益相关者的健康生活[9]。

风景园林师和城市规划师在解决这类问题上具有直接的影响力。土地使用分析和积极的规划有助于发展低影响度的聚居地，从而减少人与环境间的负面互动[9]。通过促进低地住户、山地部落族人、政策制定者和景观实践者间的合作，有望得出既尊重本土居民生活习惯，又能缓解对森林火灾影响的解决方案[60-61]。安全和适应性强的本土景观实践应当被积极推广并与森林居民的活动相融合，对农产品的需求应逐渐转为以季节性和本土性为重心，以减少农业不法行为。以上这些措施都需要在政策和景观层面作出更审慎的规划才能实现[9]。农、林业，种植咖啡、林下灌木，以及复种作物生产都可以有效对抗森林火灾[51]。以泰国清迈的Baan Doi Ngam社区为例（图2），这些措施能保护森林，并使其继续维持泰国城乡居民的身心健康。

4 健康的生态系统和人居环境研究与设计

如前文所述，清迈在人与环境的关系中存在许多问题。很多有经验的设计师、规划师和学者们也已经意识到并致力于解决这些难题。然而，由于这些问题本身的复杂性，使得解决它们非常困难。现实世界里诸如城市设计的公平性、食品安全和森林砍伐等，通常都被设计师称作“棘手问题”[62]。一般由无数个错综复杂的小矛盾交织而成，牵一发而动全身。虽然解决复杂性问题的方式同样棘手，但这些才是复杂的真实世界里最重要和最值得做的[9]。

Dyball和Newman在“人类生态理论”（Human Ecology Theory）中指出，许多试图解决复杂性问题的学者和设计师们容易着眼于小细节而忽略大局，从而陷入“复杂性困境”当中。当这种情形出现时，试图处理的细节问题会干扰研究结果或设计方案，导致最终得出的解决方法变得低效甚至失败[63-64]。他们建议学者和设计师们采用反馈指导型分析法来了解细节问题是如何与核心矛盾相关联，并得出相应的解决方案[63]。

2 Baan Doi Ngam森林下层种植的咖啡树Coffee plants underneath the forest of Baan Doi Ngam

3 可持续的城市、景观与人类健康的复合示意图[63]The complex relationship between sustainable city and landscapes and human health[63]

图3所示的研究采用了搭建概念框架的方法应对在设计健康城市环境的过程中出现的问题。该研究提取风景园林、城市规划和景观心理学领域的学术观点，形成人类健康、可持续性和自然三者间的关系示意图（图3）[65]。在整个反馈环当中正向联系最紧密的关系为人类健康指标、全球范围内对生态系统和人类健康的理解，以及与生态系统相关的设计和政策这三者之间。

这意味着在建设健康的生态系统和人居环境时，应加强环境设计与人类健康之间的关联性，进一步审视设计和研究的相互关系。在传统意义上，一般是学术研究为规划设计师提供理论支持[66]。这样的单向关系中常常出现研究理论过于陈旧而难以在设计中应用或是研究结果没有考虑现实当中的外部因素从而失效的情况。

研究和设计的关系亟须由单向转变为双向，学术研究和设计需求应形成相互不断沟通修正的动态关系。设计师须明确设计过程中涉及的研究问题，而学者也应尽力评估设计方案的效力。这样的动态关系可通过以下3种方式实现。

1）循证设计：鼓励设计师和规划师参与到以实证为基础的设计中。现阶段已有大量研究成果可被应用到设计中[67-69]。在这个新的范式中，学者们有责任指出如何将研究结果应用到设计实践，以及在实施时可能遇到的局限性。设计师和学者间应加强相互间的沟通和紧密联系。

2）基于设计的研究：学者们可参与到项目开发中并将设计项目作为其研究的问题。尽管每个项目都有特定的设计和研究问题，但探索答案的过程和对结论的阐释能对设计的探索产生更多启示。以设计为导向的研究中形成研究问题的步骤有数据收集、设计探讨和评估这3步。过程中的每一步都需根据项目的实际环境和文化背景进行详细的记录和沟通[8,66,69]。

3）使用评估及设计后评估：这一步对于设计健康的生态系统和人居环境尤为重要。设计师和学者可以制定一系列标准来测试针对不同物质文化背景所做的方案是否有效。为了更好地了解研究和设计效果，对建成项目的景观表现、生态恢复、人类感知和健康等必须进行测试[70-71]。最新技术甚至能通过环境模拟，利用机器学习或数学模型在项目建成之前测试设计方案的各项指标，使设计师和研究者们预测设计可能产生的环境效应[72-73]。文化效应也同样能通过虚拟技术进行测试[74]。然而，设计后评估很大程度上依赖于所用工具、方法的有效性，以及现行数据库，因此仍须进一步在更大范围内进行研究。

以上方法以综合协作的方式共同作用。当一个设计师或规划师对设计产生疑问时，他们可将其转化为研究问题，再在设计过程中引入调研、采访和设计实验等实证探索。最终结合研究结果而形成的设计方案便是循证设计。在设计完成之后，可在项目投入使用之前和之后再次进行使用及设计后评估。虽然不是所有项目都有足够的时间、预算和资源完成过程中的每个步骤，设计师、规划师和决策者们仍能在未来的环境设计实践中进一步探索和完善该模型。

景观和城市规划设计及研究对充满复杂难题的现实世界具有巨大影响。设计师、规划师和决策者们需要利用所有可行的方法和信息，充分发挥它们各自的作用，共同创造一个健康的生态系统和人居环境。

5 结论

为了生态系统和人类的健康而建造、设计和改善我们的建成环境需要来自学术、规划和设计界的共同努力和合作。大量的实证研究表明人类的健康离不开健康的生态系统。然而，将理论知识应用到复杂现实世界的实践过程中还有数个未被攻克的难题。笔者探讨了泰国北部有关人居环境和生态系统的三大议题，并提出了一个围绕研究、设计和实践三者间关系的新范式，包括循证设计、基于设计的研究、使用及设计后评估。在充分考虑文化和物质环境背景的情况下，该视角可被应用到泰国北部之外的任何建成环境设计中，并有望在景观和城市规划领域的学术和实践方法间建立更强大的联系。

图表来源：

图1由作者改绘自参考文献[15]；图2由作者拍摄；图3由作者改绘自参考文献[63]；表1由作者绘制。

Healthy Ecosystem Services and Healthy Human Settlements: Opportunities and Challenges in Northern Thailand

Authors: (THA) Pongsakorn Suppakittpaisarn, (THA) Vipavee Surinseng, (THA) Chulalux Wanitchayapaisit, (THA) Ekachai Yaipimol Translator: XU Qin

0 Introduction

Growing evidence shows that sustainable development for human settlements are important to human well-being. Humans benefit from healthy ecosystem in many ways, such as food provision,clean air, clean water, temperature regulation, and even pollination[1-2]. Furthermore, evidence suggests that healthy ecosystem may provide us with direct health benefits, preventing us from physical and mental morbidity and improve our executive functioning[3-4]. Thus, designers, planners, and researchers must work together to create human settlements that foster healthy ecosystem services which will in turn positively affect human health and well-being. This fact is recognized by several international organizations including Planetary Health Initiative, which agree that good planning for health and ecosystem can increase resilience from the changes in the environment, mitigate harsh environmental conditions, while promoting human health[5].

While the fields of landscape architecture and urban planning provide plenty of evidence to create such healthy settlement environments,many cities still face challenges and opportunities in its improvement[6-7]. Current knowledge in environmental design and health are still developing and filling several research gaps, and some of those gaps needed to be filled for more effective design applications[4]. Cultural and environmental contexts may dictate how designers can apply the knowledge and how effective design decisions can become. The lack of clear direction of how such collaboration may take place risks the failure in execution or delays in the progress to create healthy built environment[8].Deliberative planning and designs need all stakeholders to be involved in such process[9], and the road map of those ideas need to start with existing issues within the built environment.

Northern Thailand can be an example of the confluence between opportunities and challenges.Once occupied by Lanna Empire centered in Chiang Mai, the region connects culturally with Southern China, Myanmar, and Laos[10]. The geography of the region consists of ridges, valleys, and fan-shaped plains. It is filled with headwater forests and fertile soils and is the homes of many hilltribes and cities[11].Due to its rich history, diversity, and natural resources,Northern Thailand can become a great case study for the relationships between ecosystems and human settlements.

In this paper, three aspects of environmental and human health issues in Northern Thailand are examined. The purpose of this examination is to propose ways in which designers and researchers can collaborate to create a paradigm of landscape architecture and urban planning that create healthy ecosystems and healthy human settlements. The perspectives from this paper may shine lights on the existing gaps of knowledge in designing and planning implementation and propose the ways to continue developing the field of landscape architecture and urban planning.

1 Livable City and Environmental Justice

Built environment have direct impact on human health and well-being, urban environments even more so. The city of Chiang Mai has been designed for centuries, considering the ancient principles of planning[10,12]. However, the recent changes from the expansion in tourism, increase in population, and new technological requirements may impact the livability of the city. While the city continues to prosper, some of the residents may have been left behind[13]. Such story happens repeatedly in different cities across the world and needed to be addressed so that we can continue to create cities in which all humans and ecosystems can healthily coexist.

Chiang Mai has been a unique world-famous tourist destination with the balance of urban and natural elements. The city, especially within the city moat was built for mixed use development and contain many mature trees. Because of this, many people come to the city to live, invest, and visit and these investors, new residents, and visitors, brought the economic prosperity[14]. However, the city has its capacity, and overdevelopment has threatened the well-being of its citizen and may reduce the historical value of the city. During the year 2006—2016, the economy of the city of Chiang Mai had expanded exponentially, but with only the entrepreneur who recently moved in. By 2016, Chiang Mai had approximately 9 million tourists each year[14]. The city was densely populated with the Mueang District having 1,541 population per square kilometer, and the growth rate continued consistently[15](Fig. 1).The growth resulted in the increase of commercial districts, vendors, and the need for vehicular transportation. Public transportation, pavement,infrastructure, and green spaces are overused and overcrowded, and the city had not planned for the rapid expansion. When planners do not plan for such occurrence, the city might no longer fit the needs of its users. This affects health and well-being of the citizens.

Chiang Mai can still move forward from this point, taking the examples from model cities across the world. One of the examples is Singapore, which was introduced by then Prime Minister Lee Kuan Yew in 1967 as “the city with the densest green space.” Singapore was planned with the idea that cities with green spaces and clean environment can improve citizens well-being and invite visitors. Later,Singapore had developed into an ideal “Garden City”vision, cooperating green spaces into everyone's daily lives[16-17]. Compared to where Singapore had started,the city of Chiang Mai has large areas for public green spaces. Planners and landscape architects of Chiang Mai must consider conserving, increasing access, and improving such green spaces for the well-being.

Even with the cities that contain beautiful parks and street trees, such green infrastructure may not be equally accessible to the locals and visitors alike. The concept of equity requires that if a city is to provide opportunities of good health and wellbeing, then every citizen should be able to access them as needed[13]. In recent collaboration between Faculty of Agriculture, Chiang Mai University and the University of Hong Kong, students examined the lived spaces along the city moat area and tried to understand the changes, movements, and invisibility of people of all classes. They found that there are several faces of Chiang Mai city moat, and people do not equally gain the benefits from the moat, such as walking, biking, or using green spaces in the area as much as the others.

Limited access to green spaces and outdoor walking opportunities affect health and well-being in several ways. First, people need physical activities to remain healthy. Daily walking, jogging, and running can help prevent cardiovascular disease and morbid obesity[18-20]. Secondly, contact with nature can help reduce stress and increase attention capacity[4], thus being able to use public green spaces can improve people health and well-being for everyone. Currently,many people across the world have less opportunities to spend time outdoors due to the design of the city in which they live. Some of the obstacles toward the social equity of environmental design in most cities include the following.

1) Pedestrian accessibility: in many large cities,pedestrian access is limited or interrupted. This reduces the walkability of people who are ablebodied and removes the options for people with wheelchairs altogether[20]. In compromising street trees and traffic lanes, sometimes pedestrian access is overlooked or offered minimally.

2) Public transportation: while walkability can be helpful in a neighborhood, well-designed public transportation system may help increase physical activities and allow people to visit green spaces better[21].It may also reduce the use of personal vehicles and the use of gasoline, helping the ecosystem.

3) Perception of safety: even if shaded pedestrians and public green spaces are available,if the spaces feel unsafe, people will not use nor gain physical and mental benefits from them[22-23].Perception of safety can be planned and design by plant and construction material selections,maintenance, and cues of care[24-25].

To resolve these issues, designers and planners of Chiang Mai must make decisions towards livability and walkability of the city to improve health and well-being for its citizens. It is only when the city is livable that visitors would keep revisiting, sustaining the city's income and economic growth. Careful planning with local and commercial stakeholders and accessibility to outdoor green spaces can help create the city with environmental sustainability and justice.And only such city will foster healthy people and settlement.

2 Urban Landscapes, Agricultural Landscapes, and Food Infrastructure

People across socio-economic statuses need food. Food accessibility is one of the most important aspects of human well-being. Among the most recent Sustainable Development Goals (SDGs),ending world hunger is the first[26]. Furthermore,food can represent culture and economy. It involves the indigenous knowledge in harvesting materials,cooking methods, creating diverse eating habits,and in turn, creating the recipes in various flavors,components, and textures that become unique to its origin. Throughout the history, the international trade, global transportation, urbanization, and the flourishing of technology had created food globalization. While food globalization helps us experience variety and abundance of food that had never been accessible in the past, it greatly affects the ways in which people interact with food. These changes in eating and cooking behaviors affect the local food systems in various ways including food diversity, production, consumption, trade, access,quality, and nutrition of the food consumed by the population[27]. These changes may impact human health and well-being. For example, eating the same food for a long time can lead to obesity and malnutrition[28-29].

Food globalization, coupled with rapid urbanization, also impacts healthy ecosystems. The transformation of the existing agricultural areas into urban areas and the high demands of food demands agriculturalists to move to natural lands to produce more food crops, ignoring the importance of the ecosystems and natural limitation[27].

High food demands also lead to grand scale monocultural agriculture. Monoculture focuses on producing large quantities of food for commercialization and exports. While it makes sense economically and collaborates well with food globalization, it reduces food diversity and alters local food cultures[30]. This leads to monotonous food habits and may cause the accumulation of chemicals used to ensure the quantity of products. Some of the agricultural chemicals can lead to food toxicity or long-term health impacts such as cancer, neural damage, hormonal and immunity morbidity, and natal health issues[31]. On the other hand, indigenous agricultural practices from different cultures focus on survival, seasonal food, using natural food sources, and trade between different loci[32-33].

One way to keep the benefits of food globalization but mitigate the costs is by providing some local food infrastructure. Basic infrastructure is an important network that help citizens access the required living needs and governmental services.Usually, basic infrastructure refers to the urban transportation systems and utilities, such as roads and highways, public transportation, electricity grid, or municipal water[34]. However, a city must consider how food availability fits into the urban environment. With rapid globalization, the land use had changed, especially for agricultural lands[35].Agricultural lands have provided food for the population. In the older models, every cities and towns feed themselves, but with the increased population density and the reduction of farmlands,most cities cannot sufficiently produce their own food due to limitations including time, space,available tools, storage, and lifestyles. This leads to getting the ingredients shipped from other places or buying processed food. While such lifestyle is practical in a short run, it creates a fragile system in which an entire population depends on food transportation from other lands[27,36].

Moving forward, landscape and urban planners must implement the built environment that considers, plans, and develops for local food availability and access. This means the land use planning that considers the potential in food production opportunity and options, which will lead to how the citizens, urban and rural, reach healthier, more diverse food and live in the healthier ecosystem. The planning involved requires the perspective from land use management applied from the concept of “landscape infrastructure” that suggests that landscape should provide infrastructure for human well-being, especially food[37].

Food infrastructure provides options for people in urban, suburban, and rural areas by supporting the development of green space network along with urban development[32,38]. It also focuses on developing the potential of producing unique,local, and diverse food in the rural area in the individual and community scale. To do so, one must focus on the endemic and local food species in the rural and natural areas such as wild and herbal plants.

Chiang Mai and Northern Thailand, among other places, have the potential to create unique food infrastructure. Anderson[39]recorded more than 1,000 species utilized by the hill tribes from Northern Thailand[40]. Other work from Jacquat[41]explained the discovery of 241 species of plants including ornamental plants, ginger plants, mushrooms, palms,and bamboos from Thai local markets. A recent study also found diverse tree species in the residential gardens of Northern Thailand which contain edible leaves and fruits and can support food security and income[42]. While similar food plant diversity can also be found in Northern Thailand and any other places in the world, these studies focus on local food availability, and do not discuss the opportunity to combine the knowledge with urban development and the solutions to food scarcity.

Urban food availability issues became clearer recently considering the recent pandemic situation.With international trades cutoff, urban citizens still need to rely on food production from elsewhere.Future development of food production may help people, especially ones in lower socio-economic status, to survive if there are similar situations in the future.

Food infrastructure can appear in several contexts. In Thailand, residential garden can be an example of household food source, especially in the countryside. Most plants grew in rural residential gardens are edible. For example, Lattirasuvan has surveyed a residential harden in Phrae, a province of Northern Thailand, and found that the garden contained herbs, medicine, fruits, and starches[43](Tab. 1). In the community level, Yaipimol studied a community food source in Northeastern Thailand and found that community forests and headwater forests are parts of rural food infrastructure that provide leafy vegetables, fish, and shell fish[44].

In urban scale, the areas that can provide agricultural opportunities include productive street trees and open spaces, institutional urban agriculture such as temple, school, or governmental of fices. One case study might be a roof top garden at the Laksi Municipality Office, Bangkok, in which the of ficers can grow vegetables and can take the seeds back to their home[45]. For those with lower socio-economic statuses, community gardens and temple gardens can offer food options that fit with the cultural contexts.

There are several possibilities in designing food infrastructure. Understanding the importance of food production can lead to food infrastructure development.

Thus, landscape and urban planners must consider creating food infrastructure in the urban environment, in which we provide local, diverse food. Such development should examine possible policies, planning, and design for food infrastructure along with other infrastructure. This concept is important for urban food security, provides food options and accesses to the city's population, and improves urban ecosystem[46]. This will in turn promote sustainable urban development, diverse cultural experience for residents and visitors, and enhance the ecosystem services toward everyone in the built environment[47].

3 Forest Landscapes, Air Pollution,and Water Safety

While most of human settlements are in the urban and suburban areas, the relationships between humans and forests can have large impact towards ecosystem and human health alike. The forests in Northern Thailand are important to the well-being of humans and animals across the country. Its ecosystem service provides rich and diverse food source, medicinal plants, and timber for habitat and fuel[48-49]. Furthermore, Thai forests help mitigate flood and landslide for the settlements of the lower regions[50]. Furthermore, headwater forests provide essential clean water for everyone from the hilltribes to the coastal cities of Central Thailand[51].In addition, these diverse forests regulate humidity,carbon sequestration, and airborne particulate matters[52]. Thus, aside from their intrinsic values,Northern Thai forests and its health have direct health and well-being impacts for its entire nation.

However, Thai forests are at risks. The mountainous ecosystem commonly found in Northern Thai forests is the most fragile due to steep slopes, global climate changes, and recent human activities and settlements[53]. While deforestation had slowed in recent years[53], the missing forests still left great impacts toward the ecological well-being of the region. Designers and planners must work together to restore it to its original stage.

Northern Thai forests are parts of the complex problem most known to Chiang Mai and neighboring regions regarding ecosystem and human settlements: the air pollution[54]. During its haze season, Chiang Mai had the highest rate of measured PM2.5in the world[55]. PM2.5is the dust particle smaller than 2.5 nanometer in diameter. While the rate of PM2.5had only been measured for the past few years,the air pollution had been recorded since 1987 and began to intensify greatly in recent years[8,56].

High PM2.5level risk million deaths and morbidity regarding respiratory and circulatory systems for people of Northern Thailand[54],especially for the vulnerable population such as pregnant women, elderly, and children. Exposure to these particulate matters might cause coughing and wheezing in short term, asthma and lung cancer in longer terms, and finally, fatality[7,57].

The PM2.5issues came from several reasons.However, one of the main causes is forest fires.Forest fires in Northern Thailand are seasonal and common[53]. However, its growing issues come from the interaction between human settlements and the environment. Climate change, both natural and man-made had contributed to the dryer dry seasons which can create longer, more intense flames[58].Forest managements can also impact the intensity and the spread of the fire[59]. Finally, the interaction between local lowlanders and folks from the hill tribes contribute to the issue via burning to hunt,collect mushrooms, and to farm. These practices,when done in small scale, were parts of the human ecology and caused little effects[59-60]. However, with the growing demands of agricultural goods and by products, the scale of forest fire had led to the intensity of air pollution Northern Thailand is facing and the dramatic deforestation which exacerbate the issue further[59].

Another issue emerges from deforestation:water scarcity. Human health and well-being depend on the access to clean water. Deforestation of the Northern Thailand forest may impact the availability of the water resources in the lower regions of Thailand. Clean water is needed to help balance temperature and maintain bodily function.Furthermore, agriculturalists need water to produce food[61]. Without the most important headwater resources, most people would face great well-being risks, economically and medically.

In the past, Thailand had made progress in reducing deforestation and agricultural malpractice.Many settlements were moved from headwater highlands to the less ecologically fragile lowlands.Some agricultural practices were added to mitigate deforestation[60]. However, many sensitive problems remain, such as settlements in headwater forests, the investments in industrial agriculture, and the overcapacity of tourism[59]. These problems needed to be closely examined from all sides and the solutions must be generated in the ways that improve the wellbeing of all stakeholders[9].

Landscape architects and urban planners can have direct impact on these issues. Analysis of land use and active planning can help develop low impact settlements to reduce the negative interactions between humans and nature[9]. The collaboration between lowlanders, hill tribes, policy makers, and landscape practitioners must be done to create the solution that respect the lifestyles of the locals while mitigate the effects of forest fires[60-61]. Safe and resilient indigenous landscape practices need to be introduced and integrated back into the practice of those settlements in the forests, while the demands of the agricultural goods may needed to be focused based on seasonality and locality to reduce agricultural malpractices. These solutions may need deliberative planning, both at policy and landscape levels[9]. Agroforestry, growing coffee or undergrowth under the forest layers, and multiple crops productions are some ways that can be used to forest burning[51], such as an example from Baan Doi Ngam community in Chiang Rai, Thailand(Fig. 2). With these applications, the forests can remain to protect the health and well-being from both urban and rural people across Thailand.

4 Research and Design for Healthy Ecosystem and Healthy Settlements

As presented in previous sections, Chiang Mai, like every settlement, has some issues in the relationship between human and environment.Many experienced designers, planners, or researchers already know these issues and are working towards solving the problems. However, these issues are usually difficult to solves due to their complexity.Real world problems, such as equity in urban design,food security, and deforestation are what designers call “messy problems”[62]. They are the problems that are made of overlayered webs of smaller problems that tangle together, affecting one another. Because they are messy problems, they are very messy to solve, but these problems are what matter in the real and complex world[9].

In the Human Ecology Theory, Dyball &Newman argues that trying to solve problems like these may lead to “Complexity Dilemma” which may lead to researchers or designers trying to focus on small chains of issues and ignore the overall picture. When that happens, factors outside of the issues we are trying to solve would interrupt the research findings or design interventions, causing the solutions to be less effective, or at times, fail[63-64].They suggest that researchers and designers use the feedback-guided analysis to place how smaller issues are linked to the main problems and plan to address them accordingly[63].

A study had used conceptual framework development method to resolve such issues in designing healthy and healthful urban environment.Using the ideas from scholars in landscape architecture, urban planning, and landscape psychologists to place the relationships between human health, sustainability, and importance of nature (Fig. 3)[65]. The strongest positive links in this feedback loop are the links between human health indicators, global understanding of the link between ecosystem and human health, and designs and policies regarding the ecosystem.

This means that to move towards creating healthy ecosystems and healthy human settlements,more links between environmental design and human health needs to be established and communicated.To do so, the relationships between design and research needs to be examined. In the traditional relationships between research and design, research provides design theories to designers and planners[66].Such relationship is one sided and can lead to stale research which may not be applied in design at all,or the research findings fail to be executed when the designs are implemented due to outside factors not shown during the research environment.

A paradigm shift of research and design relationships is on its way, but proposals need to be made to link scholarly research and real world designs: a two way relationship in which research and design demands and inform each other in dynamic ways. For example, designers must identify research questions found in their design issues, and researchers must seek to evaluate the effectiveness of design solutions. Such new dynamic may manifest in several ways, including the following.

1) Evidence-Based-Design: designers and planners must be encouraged to engage in design based on empirical evidence. In the current world,there are many research results already available that can be applied to design[67-69]. In this new paradigm, it is also researcher's responsibility to suggest how their research findings may apply to the design solutions,and where the limitations on the implementation may apply. Both designers and researchers must communicate clear and strong links between each other.

2) Research-by-Design Methods: researchers can engage in project developments and use design project as research questions. While each project has unique and specific design and research questions,the methods in finding out those solutions and the interpretation of some findings may inform other design inquiries. Research by design methods generate clear research questions in three steps:database collection, design inquiry, and evaluation.The processes of these methods must be recorded and communicated clearly, along with their physical and cultural contexts and limitations[8,69-70].

3) Post Occupancy Evaluation and Post-Design Evaluation: This step is most important when designing for health of ecosystem and humans. How do designers know that the designs they had done in the past are effective? Designers and researchers could design the studies that test the effectiveness of the designs for both physical and cultural outcomes.Landscape performance, ecological restoration, and human perceptions and well-being must be tested for the completed and operating projects to the better understanding of research and design[71-72].Furthermore, recent technology may allow us to test the effectiveness of a design before it was built. By modeling the environment and test them via machine learning or mathematical models,designers and researchers can predict environmental outcomes of the design[73-74]. Cultural outcomes can also be tested by virtual technology[75]. However,the effectiveness of post-design evaluation depends greatly on the effectiveness of tools, methods, and existing database available and must be investigated further as a grand-scale effort.

These tools work together in an integrative way. For example, once a designer or planner has a design inquiry, they can turn the inquiry into research questions. They can then combine empirical explorations, such as surveys, interviews, and design experiments within the design process. Combined with previous research findings, the design decisions derive are evidence-based design. After the design is finished, it can be tested again before and after the implementation and uses for the post-design evaluation and post occupancy evaluation. While not all design projects can be conducted in this completed process due to time, budget, or resource limitations, the model is worth exploring and improvising as designers, planners, and decision makers progress into the future of environmental design.

Landscape design and urban planning research and designs make strong impact to the real world,and the real world is a complex place filled with complex issues. It is important for designers,planners, and decision makers, to utilize the available tools and information and apply them accordingly to create healthy ecosystems and healthy settlements.

5 Conclusion

Building, designing, and improving the built environment for the health of ecosystems and humans need collaboration between research,planning, and design. Large body of empirical evidence connects healthy ecosystems with healthy people. However, several questions remain in implementing the knowledge into the real world's complexity. Three issues regarding the relationships between humans, settlements, and ecosystems in Northern Thailand had been examined, and a new paradigm for the relationships between research,design, and implementation had been proposed including the emphasis on evidence-based design,research-by design methods, and post-occupancy or post-design evaluations. The new perspective may be used to apply in any design of the built environments outside of Northern Thailand,considering the cultural and environmental contexts and may results in the stronger relationship between the scholastic and practical approaches of landscape architecture and urban planning.

Sources of Figures and Table:

Fig. 1 modified from reference [15]by the authors; Fig. 2 ©the authors; Fig. 3 modified from reference [63]by the authors; Tab. 1 © the authors.

(Editor / WANG Yaying)