The main purpose of this study was to examine the influence of visible greenness rate, green coverage ratio and distance from plants on human perceptions and parameters of the physical environment. A secondary purpose was to explore the correlation between parameters of physical environment and human perceptions when indoor plants were present. A randomized controlled trial was conducted. Experimental treatments were administered by placing either three or eight pots of Radermachera hainanensis Merr. in a room. Sixty students of a technology university in central Taiwan were recruited as participants, and their perceptions were collected using a questionnaire. Physical parameter data were collected using two air quality detectors. The results indicated the following: when the visible greenness rate was identical, different green coverage ratios and plant–participant distances did not exert different effects on participants' perceptions. Different green coverage ratios and distances from plants exerted differing effects on physical parameters. However, the distance from indoor plants had stronger and more consistent effects on physical parameters than the green coverage ratio. The environmental comfort of the participants increased with the CO2 level, and the lower the level of total volatile organic compound, the higher is the level of surprise.
BringslimarkTHartigTPatilG.The psychological benefits of indoor plants: a critical review of the experimental literature. J Environ Psychol2009; 29: 422–433.
3.
SmardonRC.Perception and aesthetics of the urban environments: review of the role of vegetation. Landscape Urban Plan1998; 15: 85–106.
4.
DravigneAWaliczekTMLinebergerRDZajicekJM.The effect of live plants and window views of green spaces on employee perceptions of job satisfaction. HortScience2008; 43: 183–187.
5.
CetinMSevikH.Change of air quality in Kastamonu city in terms of particulate matter and CO2 amount. Oxid Commun2016; 39: 3394–3401.
6.
CowardMRossDCowardSCaylessSRawG. Pilot study to assess the impact of green plants on NO2 levels in homes. Building Research Establishment Note N154/96. Watford, UK, 1996.
7.
GopalakrishnanVZivGHirabayashiSBakshiBR.Nature-based solutions can compete with technology for mitigating air emissions across the United States. Environ Sci Technol2019; 53: 13228–13237.
8.
IrgaPJTorpyFRBurchettMD.Can hydroculture be used to enhance the performance of indoor plants for the removal of air pollutants?Atmos Environ2013; 77: 267–271.
9.
KimKJKilMJSongJSYooEHSonK-CKaysSJ.Efficiency of volatile formaldehyde removal by indoor plants: contribution of aerial plant parts versus the root-zone. J Am Soc Hort Sci2008; 133: 521–526.
10.
OrwellRLWoodRATarranJTorpyFBurchettMD.Removal of benzene by the indoor plant/substrate microcosm and implications for air quality. Water Air Soil Pollut2004; 157: 193–207.
11.
SevikHCetinMOzelHBAkarsuHCetinIZ.Analyzing of usability of tree-rings as biomonitors for monitoring heavy metal accumulation in the atmosphere in urban area: a case study of cedar tree (Cedrus sp.). Environ Monit Assess2020; 192: 23.
12.
SevikHCetinMUcun OzelHOzelHBMossiMMMZeren CetinI.Determination of Pb and Mg accumulation in some of the landscape plants in shrub forms. Environ Sci Pollut Res2020; 27: 2423–2431.
13.
SevikHSalehEAACetiaM. Change of the air quality in the urban open and green spaces: Kastamonu sample. In: Koleva I, Yuksel UD and Benaabidate L (eds) Ecology, planning and design. Sofia: St. Kliment Ohridski University Press, 2017, pp.409–422.
14.
WolvertonBCJohnsonABoundsK.Interior landscape plants for indoor air pollution abatement. Davidsonville, MD: National Aeronautics and Space Administration, 1989.
15.
WoodRABurchettMDAlquezarROrwellRLTarranJTorpyF.The potted-plant microcosm substantially reduces indoor air VOC pollution. I. Office field-study. Water Air Soil Pollut2006; 175: 163–180.
16.
YooMHKwonYJSonK-CKaysSJ.Efficacy of indoor plants for the removal of single and mixed volatile organic pollutants and the physiological effects of the volatiles on the plants. J Am Soc Hortic Sci2006; 131: 452–458.
17.
BaoshengKShibataS-ISawadaAOyabuTKimuraH.Air purification capability of potted Phoenix roebelenii and its installation effect in indoor space. Sens Mater2009; 21: 445–455.
18.
KerschenEWGartenCWilliamsKADerbyMM.Evapotranspiration from spider and jade plants can improve relative humidity in an interior environment. HortTechnology2016; 26: 803–810.
19.
RuanH-C.A strategy study on the effect of reduce formaldehyde concentration by indoor foliage plant under different spectra. J Inter Des2012; 14: 11–22.
20.
BringslimarkTHartigTPatilGG.Psychological benefits of indoor plants in workplaces: putting experimental results into context. HortScience2007; 42: 581–587.
21.
CetinM.The effect of urban planning on urban formations determining bioclimatic comfort area's effect using satellitia imagines on air quality: a case study of Bursa city. Air Qual Atmos Health2019; 12: 1237–1249.
22.
CetinMAdiguzelFGungorSKayaESancarMC.Evaluation of thermal climatic region areas in terms of building density in urban management and planning for Burdur, Turkey. Air Qual Atmos Health2019; 12: 1103–1112.
23.
HullRB.How the public values urban forests. Arboric J1992; 18: 98–101.
24.
UlrichRS.The psychological benefits of plants. The Garden1984; 8: 16–21.
25.
UlrichRS.View through a window may influence recovery. Science1984; 224: 420–421.
26.
HanK-TRuanL-W.Effects of indoor plants on self-reported perceptions: a systemic review. Sustainability2019; 11: 4506.
27.
HanK-TRuanL-W.Effects of indoor plants on air quality: a systemic review. Environ Sci Pollut Res2020; 27: 16019–16051.
28.
U.S. Environmental Protection Agency. Report to Congress on indoor air quality: Volume 2. EPA/400/1-89/001C, 1989. Washington, DC.
29.
World Health Organization.World health report. Geneva: World Health Organization, 2001.
30.
PocockD.Sight and knowledge. Trans Inst Br Geogr1981; 6: 385–393.
31.
HanK-T.Urban forestry: theories and applications. Taipei: Lamper, 1998.
32.
HongX-M.A study on restoration effects of greening levels of plant at indoor working environment. Unpublished Master’s Thesis, University of Feng Chia, Taichung, 2009.
33.
LiuM Kim EMattsonRH.Physiological and emotional influences of cut flower arrangements and lavender fragrance on university students. J Ther Hortic2003; 14: 18–27.
34.
HanK-T.Influence of passive versus active interaction with indoor plants on the restoration, behavior, and knowledge of students at a junior high school in Taiwan. Indoor Built Environ2018; 27: 818–830.
35.
LarsenLAdamsJDealBKweonB-STylerE.Plants in the workplace: the effects of plant density on productivity, attitudes, and perceptions. Environ Behav1998; 30: 261–281.
36.
HanK-T.Effects of indoor plants on the physical environment with respect to distance and green coverage ratio. Sustainability2019; 11: 3679.
ShibataSSuzukiN.Effects of an indoor plant on creative task performance and mood. Scand J Psychol2004; 45: 373–381.
39.
HungC-YHanK-T.Effect of classroom greenness on students’ psycho-physiology, performance, and health at the Shin-Kuang Junior High School, Taichung County. Sci Agric2010; 58: 89–106.
40.
HanK-THungC-Y.Influences of physical interactions and visual contacts with plants on students’ psycho-physiology, behaviors, academic performance, and health. Sci Agric2012; 59: 195–210.
41.
HanK-THungC-Y.Influences of plants and their visibility, distance, and surrogate in a classroom on students’ psycho-physiology. J Archit Plan2011; 12: 1–22.
42.
JiangBLiDLarsenLSullivanWC.A dose-response curve describing the relationship between urban tree cover density and self-reported stress recovery. Environ Behav2016; 48: 607–629.
43.
JiangBLarsenLDealBSullivanWC.A dose-response curve describing the relationship between tree cover density and landscape preference. Landscape Urban Plan2015; 139: 16–25.
44.
StapletonERuiz-RudolphP.The potential for indoor ultrafine particle reduction using vegetation under laboratory conditions. Indoor Built Environ2018; 27: 70–83.
45.
KimKJKilMJJeongMIKimHDYooEHJeongSJPakCHSonKC.Determination of the efficiency of formaldehyde removal according to the percentage volume of pot plants occupying a room. Korean J Hortic Sci Technol2009; 27: 305–311.
46.
United Nations. World urbanization prospects: the 2014 revision. Highlights (ST/ESA/SER.A/352). United Nations, New York, USA, 2014.
47.
World Medical Assembly. Declaration of Helsinki. World Medical Assembly, Tokyo, Japan, 1975.
48.
CookTDCampbellDT.Quasi-experimentation: design & analysis issues for field settings. Boston, MA: Hougton Mifflin, 1979.
49.
LinF-XLiZ-T.Breeding, cultivation and application of Hainan bean tree in landscape. Anhui Agric Sci Bull2014; 20: 109–110.
50.
GongJ.Human scale and indoor space. Taipei: Bo-Yuan Publishing, 2000.
51.
SmardonRCPalmer JF and FellemanJP.Foundations for visual project analysis. New York: Wiley, 1986.
52.
ChenY-CLinY-J.Enclosure of city streetscapes. J City Plan2014; 41: 99–115.
53.
HartigT.Testing restorative environments theory. Unpublished doctoral dissertation, University of California, Irvine, CA, 1993.
54.
KaplanRKaplanS.The experience of nature: a psychological perspective. New York, NY: Cambridge University Press, 1989.
55.
YiY-K.Affect and cognition interface in aesthetic experiences of landscapes. Unpublished doctoral dissertation, Texas A&M University, College Station, TX, 1992.
56.
HanK-T.An empirical approach to Feng Shui in terms of psychological well-being. J Ther Hortic2006; 17: 8–19.
57.
WhiteEVGaterslebenB.Greenery on residential buildings: does it affect preferences and perceptions of beauty?J Environ Psychol2011; 31: 89–98.
58.
HanK-T.Influence of limitedly visible leafy indoor plants on the psychology, behavior, and health of students at a junior high school in Taiwan. Environ Behav2009; 41: 658–692.
59.
FrontczakMWargockiP.Literature survey on how different factors influence human comfort in indoor environments. Build Environ2011; 46: 922–937.
60.
FrontczakMAndersenRVWargockiP.Questionnaire survey on factors influencing comfort with indoor environmental quality in Danish housing. Build Environ2012; 50: 56–64.
61.
FryGTveitMSOdeAVelardeMD.The ecology of visual landscapes: exploring the conceptual common ground of visual and ecological landscape indicators. Ecol Indic2009; 9: 933–947.
62.
SimoničT.Preference and perceived naturalness in visual perception of naturalistic landscapes. J Biotechnol2003; 82: 369–387.
63.
TveitMOdeÅFryG.Key concepts in a framework for analyzing visual landscape character. Landscape Res2006; 31: 229–255.
64.
Berman HoutMCKardanOHunterMRYourganovGHendersonJMHanayikTKarimiHJonidesJ.The perception of naturalness correlates with low-level visual features of environmental scenes. PLoS ONE2014; 9: e114572.
65.
JunkerBBucheckerM.Aesthetic preferences versus ecological objectives in river restorations. Landscape Urban Plan2008; 85: 141–154.
66.
MackayGJNeillJT.The effect of “green exercise” on state anxiety and the role of exercise duration, intensity and greenness: a quasi-experimental study. Psychol Sport Exerc2010; 11: 238–245.
67.
MarselleMRIrvineKNLorenzo-ArribasAWarberSL.Moving beyond green: exploring the relationship of environment type and indicators of perceived environmental quality on emotional well-being following group walks. Int J Environ Res Public Health2015; 12: 106–130.
68.
MarselleMRIrvineKNLorenzo-ArribasAWarberSL.Does perceived restorativeness mediate the effects of perceived biodiversity and perceived naturalness on emotional well-being following group walks in nature?J Environ Psychol2016; 46: 217–232.
69.
van den BergAEJorgensenAWilsonER.Evaluating restoration in urban green spaces: does setting type make a difference?Landscape Urban Plan2014; 127: 173–181.
70.
van den BergAEKooleSLvan der WulpNY.Environmental preference and restoration: how are they related?J Environ Psychol2003; 23: 135–146.
71.
HoL-CChangC-Y.Establishing indicators of perceived naturalness. J Art Des Huafan Univ2016; 11: 63–73.
72.
LeeT-HCromptonJ.Measuring novelty seeking in tourism. Ann Tourism Res1992; 19: 732–751.
73.
ChengC-KShenLChonJ-H.Examining the effects of familiarity on landscape perception within different contexts. J Outdoor Recreat2009; 22: 1–21.
74.
PearsonPH.Relationships between global and specified measures of novelty seeking. J Consult Clin Psychol1970; 34: 199–204.
75.
BalogluS.Image variations of Turkey by familiarity index: informational and experiential dimensions. Tourism Manage2001; 22: 127–133.
76.
IzardCE.The fact of emotion. New York: Appleton-Century-Crofts, 1971.
77.
IzardCEBuechlerS.Aspects of consciousness and personality in terms of differential emotional theory. In: RPlutchikHKellerman (eds) Emotion: theory, research, and experience. New York: Academic Press, 1980, pp.165–187.
78.
BishopIDHullRB.Integrating techniques for visual resource management. J Environ Manage1991; 32: 295–312.
79.
IttelsonWHProshanskyHMRivlinLGWinkelGH.An introduction to environmental psychology. New York: Holt, Rinehart and Winston, 1974.
80.
MandlerG.Mind and body psychology of emotion and stress. New York: W.W. Norton, 1984.
81.
MehrabianARussellJA.An approach to environmental psychology. Cambridge, MA: The MIT Press, 1974.
82.
WuM-L.SPSS operation and application—practice & analysis of variance. Wunan Press: Taipei, 2010.
83.
WuM-LChangY-R.SPSS [PASW] and statistical application analysis I. Wunan Press: Taipei, 2011.
84.
DeVellisRF.Scale development theory and applications. London: SAGE, 1991.
85.
Government of Republic of China. Indoor Air Quality Act Standards. Executive Yuan, Taipei, Taiwan, November 23 2011.
86.
Bakó-BiróZWargockiPWyonDFangerP. Indoor air quality effects on CO2 levels in exhaled air during office work. In: Indoor air 2005: proceedings of 10th international conference on indoor air quality and climate, Beijing, China, September 4–9 2005; pp.76–80.
87.
MuiKWTsangTWWongLTYuY.Evaluation of an indoor environmental quality model for very small residential units. Indoor Built Environ2019; 28: 470–478.
88.
ZhangJJSmithKR.Indoor air pollution: a global health concern. Br Med Bull2003; 68: 209–225.
89.
FangerPO.Thermal comfort: analysis and application in environmental engineering. New York: McGraw-Hill, 1970.
90.
WalkerEHernandezAVKattanMW.Meta-analysis: its strengths and limitations. Cleve Clin J Med2008; 75: 431–439.
91.
WangH-L.A study of the greenness visual evaluations of urban parks. J Des1999; 4: 61–89.
92.
KimH-HLeeJ-YKimH-JLeeY-WKimK-JParkJ-HShinD-CLimY-W.Impact of foliage plant interventions in classrooms on actual air quality and subjective health complaints. J Japan Soc Hort Sci2013; 82: 255–262.
93.
WolvertonBC.How to grow fresh air: 50 houseplants that purify your home or office. New York: Penguin Books, 1996.
94.
World Health Organization. Preamble to the Constitution of WHO as adopted by the International Health Conference, New York, 19 June–22 July 1946; signed on 22 July 1946 by the representatives of 61 States (Official Records of WHO, no. 2, p. 100) and entered into force on 7 April 1948.
