Published at : 18 Sep 2024
Volume : IJtech
Vol 15, No 5 (2024)
DOI : https://doi.org/10.14716/ijtech.v15i5.6958
Natasia Heindri | Architectureal Sciences and Building Technology Research Cluster, Department of Architecture, Faculty of Engineering, Universitas Indonesia, Kampus Baru UI Depok 16424, Indonesia |
Ova Candra Dewi | 1. Architectureal Sciences and Building Technology Research Cluster, Department of Architecture, Faculty of Engineering, Universitas Indonesia, Kampus Baru UI Depok 16424, Indonesia. 2. Graduate Prog |
Nandy Putra | Department of Mechanical Engineering, Faculty of Engineering, Universitas Indonesia, Kampus Baru UI Depok 16424, Indonesia |
Andrew Flynn | School of Geography and Planning, Cardiff University, Glamorgan Building, King Morgan VII Avenue, Cardiff, Walles, United Kingdom |
Tika Hanjani | Architectureal Sciences and Building Technology Research Cluster, Department of Architecture, Faculty of Engineering, Universitas Indonesia, Kampus Baru UI Depok 16424, Indonesia |
Kartika Rahmasari | Architectureal Sciences and Building Technology Research Cluster, Department of Architecture, Faculty of Engineering, Universitas Indonesia, Kampus Baru UI Depok 16424, Indonesia |
Rapid urban development, along with high population
growth in Indonesia, has forced some communities to move away from the city
center. At the same time, the city needs space for its waste, which is
typically deposited in landfill sites. In both cases, the city outskirts have
become favored sites for development. As a result, some communities now find
themselves living adjacent to a landfill site and must cope with its air
pollution. This study assesses the application of a vertical greenery system
(VGS) acting as a microbial air quality filter for community houses located
near the landfill site in Kampung Nambo in South Tangerang, Indonesia. Six
types of plants were selected for analysis. The study found that Hedera helix
was the most effective plant for filtering microbes from the air; the highest
recording was reaching 717.3 CFU/m3 (day 10). The study also
highlighted the presence of solar radiation, additional shading, and natural
ventilation combined with the VGS help to improve air quality. Higher temperatures
can reduce the microorganisms, thus impacting the number of bacteria and fungi.
Every 1 W/m2 increase in solar radiation can reduce bacteria by 1.98
to 2.16 CFU/m3. Furthermore,
the insights of this study should encourage both governmental decision-makers
and the broader community to reexamine the importance of vertical greening in
settlements adjacent to a landfill.
Air quality; Dense settlement; Landfill; Vertical greenery system
Indonesia experiences high
humidity ranging from 55% to 100% along with daytime temperatures between 20°C
to 32°C, and nighttime temperatures between 21°C to 27°C (Direktorat Jenderal Cipta Karya, 2020). These climatic conditions,
together with Indonesia becoming one of the top twenty most polluted countries
globally (The World Bank, 2022), can combine to
produce potentially adverse health effects (Ahad et al., 2020). Additionally,
the country's population has experienced a 211% increase from 1960 to 2022,
with significant growth occurring in urban areas
Building
practitioners face challenges in considering future climate conditions in
construction and retrofitting projects. Currently, there is a growing focus on developing models and gathering
evidence to support the creation of more resilient buildings. One area of
growing interest is in implementing Vertical Greenery Systems (VGS) to improve
building envelope performance and address multifunctional benefits for dense
settlements and nature
An
early study on VGS by Zaid found that it can lower air pollution in a tropical
context (Zaid et al., 2018). Subsequent
work by Megahed and Ghoneim on spaces in densely populated residential areas
discussed the use of VGS on building facades for natural ventilation, air
quality management, thermal comfort, and green spaces (Megahed and Ghoneim, 2021).
A vibrant debate is emerging on the applicability and efficacy of VGS in
various settings
Figure
1 Study
framework and keywords compilation
2.1. The impact of landfill sites, microbial air quality, and health
Landfill
sites are formal locations to manage garbage responsibly for people and the
environment. In practice, that may not always be the case. A landfill site near
housing settlements and other sensitive locations, such as a market or a
waterway, is considered unsafe and a threat to public health that needs to be
adequately managed (Daniel et al., 2021). Moreover,
waste decomposition generates methane (CH4) and hydrogen sulfide (H2S),
which have a bad odor and may attract rats, while ammonia (NH3)
causes respiratory illnesses, physiological abnormalities in the lungs, and
elevated blood pressure (Axmalia and Mulasari, 2020).
Along with chemicals, biological pollutants such as bacteria and fungi are
transported by air circulation in the landfill area (Pepper and Gerba, 2015).
As we are keen to emphasize throughout local conditions matter. In this case,
local biometeorological factors such as temperature, pressure, relative
humidity, wind direction, and the substance of waste and leachate create an
impact on pathogenic agents’ ability to survive and multiply
2.2. Vertical Greenery Systems (VGS)
The
VGS is categorized as a green facade (GF) or a living wall (LW) based on its
construction type and diversity of plants
VGS
can act as a natural air conditioner to absorb heat
Grass
and ornamental plants in VGS, such as Cordyline
fruticosa, Phyllanthus cochinchinensis, Nephrolepis exaltata, and
ornamental plants like Philodendron
burle-marxii can reduce heat and air pollution (Ghafar et al., 2020). While
other plant species can also be used with VGS to filter airborne particles,
like Dracaena deremensis, Neomarica
gracilis, Philodendron cordatum, Schlumbergera truncata Hybrids, Monstera
deliciosa, Nephrolepis biserrata, Hoya pubicalyx, and Cissus rhombifolia (Ghazalli et al., 2018).
In addition, Hedera helix plants with a 20 cm thickness are not only
capable of reducing heat but also acting as a wind barrier (Kraus, Žáková and Žák, 2020; Castellanos-Arévalo et al.,
2016; Minister of Health Republic of Indonesia, 2011).
The density of Passiflora plants is expected to impact the thermal experience
Biochar
is frequently used to boost the viability and efficacy of VGS (Kraus, Žáková and Žák, 2020).
Based on a preliminary study from Puteri (2016),
59 plant species were examined to see which had the best pot systems for VGS. Alternanthera ficoidea stood out for
having the highest index value for plants' capacity to produce the maximum
supply of 18 O2/m2 with a leaf area of 44 cm2.
As well as Codiaeum variegatum and
other plants with an index of 12. In addition, Philodendron sp., with a leaf area of 363 cm2 and an
index value of 8, performs well. It is, though, important to evaluate plant
performance in a variety of local settings to be confident of their
effectiveness, including their acceptability to communities and this will often
mean that they are plants recognized locally. For our study, it involves examining the purification abilities of
plants in close proximity to a landfill site, taking into account the hot and
humid climate of Indonesia.
The
anaerobic decomposition of microorganisms in landfills produces ammonia gas (NH3),
which encourages the growth of bacteria, especially from organic waste (Yang et al., 2023a).
According to the Indonesian health standard, the upper range for germ threshold
with harmful fungi and bacteria is 700 CFU/m3 (Minister of Health Republic of Indonesia, 2011).
International standards, such as the American Conference of Governmental
Industrial Hygienists (ACGIH), are stricter and set a threshold of 500 CFU/m3.
This more demanding requirement has become mandatory for some tropical
countries, such as Brazil and Singapore (Castellanos-Arévalo et al., 2016).
Another challenge for many landfill sites in Indonesia, including our case
study, arises from biological activity brought on by sewer decomposition and
stagnant water. This results in the formation of hydrogen sulfide gas (H2S),
which has a strong odor (Elwood, 2021; Azima, 2016).
Previous research has suggested that vegetation can be used to reduce high
levels of bacteria and fungi in settlement areas near landfills (Fithri, 2021; Kumar et al., 2019). However, where land is scarce,
as in our case study, there are limited opportunities to create traditional
vegetation barriers.
A
previous study by Rakhshandehroo mentioned that VGS is primarily applied on the
façade with varying degrees of installation complexity to support building
performance, such as reducing noise and insulating the building's envelope
through solar reflection, heat transfer from the leaves and photosynthesis or
evapotranspiration, among other things (Rakhshandehroo, Mohd-Yusof, and Deghati-Najd, 2015).
Additionally, VGS has been found to reduce energy usage from 9.5% to 18% in
commercial buildings and decrease the harmful effects of UV light on the
building's (Rakhshandehroo, Mohd-Yusof, and Deghati-Najd, 2015; Sathien,
Techato and Taweekun, 2013).
2.3.
VGS and shading: reducing solar radiation
The
range of optimal daylight intensity for housing in a tropical climate is about
3–7 W/m2 (DKI Jakarta Provincial Government, 2012). Lighting and ventilation are
frequently connected. Therefore, external improvements, such as adding shade in
the form of trees or air bricks and patterned tiles, can lower temperatures in
settlements to between 18°C and 30°C and ameliorate internal comfort (Kusumawardhani, 2011; Minister of Health Republic of
Indonesia, 2011). Well-planned shade can increase
a city's aesthetic appeal lessen the consequences of heat generation
3.1. Case Study: Kampung Nambo, South Tangerang,
Indonesia
South
Tangerang City is one of the fastest-growing cities in Indonesia and is close
to Jakarta. South Tangerang’s landfill is located in Kampung Nambo. The
community next to the landfill site is home to 40% of the households in Kampung
Nambo (Dewi et al., 2019). The area was chosen as a case
study due to its environmental issues.
The
average temperature is measured daily for the whole year during the study to be
between 27.46°C and 28.04°C. Climate change is likely to lead to further
increases in average temperature, making efforts to improve cooling within the
community even more important. Like other tropical areas, local weather has a
rainy season. This means that there is a high average annual humidity of around
80%. The average wind speed is between 1.44 and 1.57 m/s
Data
sets were collected during the ‘shifting season’ in Indonesia - the time
between dry and rainy seasons – for six weeks between March and April 2022.
This study captured data
Figure 3 Experiment Box Model Placement in Kampung Nambo Serpong, RT 03 RW 04,
South Tangerang City
3.3.1. Plant Selection