PTT Protection Strip and Buffer Zone

designed by /

Location: Thailand / Type: Forest / Infrastructure / Built: 2018 /
Published on October 18, 2021

Goals and Objectives

PTT Protection Strip and Buffer Zone is a series of landscape buffer design, surrounding the boundary of petroleum, gas and oil depots throughout Thailand. The protection strips are adapted from the original Dr. Akira Miyawaki’s eco forest technique, which is widely used in Japan industrial development in order to provide sufficient buffer area between the industrial areas and the surrounding communities. PTT adopted this idea and techniques and applied at the petroleum, gas and oil depots. The protection strips usually surround the perimeter of the site, and are designed with additional intention to create a better environment at the depots that can be shared with the local communities. Landscape will be re-created as great as a functioning forest, bringing numerous environmental benefits to the site and the local communities.

Site Locations and Analysis

Many PTT Protection Strips and Buffer Zones for petroleum, gas and oil depots have been designed and implemented in various locations across the country, including Phuket, Lampang, Phitsanulok, Den Chai Phrae, Si Racha Chonburi, Rongpo Chonburi, Saraburi, Khon Kaen, Surat Thani, Songkhla, and Khanom Nakhon Si Thammarat. Each location has their unique landscape characters and constraints, challenging the design team to learn and adopt the eco forest techniques to each site.

Design Criteria

The standard protection strip with planting is set at 30m wide. However, the size of protection strips varies due to different site constraints, such as limited site area, surrounding industrial pipes of drainage, gas and electricity along the site periphery, blockage of CCTV visibility, and security and maintenance issues.


Density of Plants

Protection strip with eco forest buffer results in higher density of plants. The technique includes randomly planted mixed saplings with density of 4 saplings/ m2 on a raised fertile berm, with good irrigation system. The eco forest buffer will gradually adapt to the natural processes and require lesser maintenance. With the principle of survival of the fittest, only the healthiest saplings will continue to thrive at the eco forest, forming a strong and stable eco forest system.

Mixture of Soil

Saplings thrive in a good quality of eco forest berm, with fertile loamy soil, good water source, sufficient sunlight, good ventilation of air and aeration in the soil. The organic soil mix shall follow these general guidelines:

  • Top soil pH 6 – 7.5
  • humidity lower than 25%
  • mix with soil amendment for lightweight character
  • coconut husk chips or rice husk
  • chicken manure

Combination of Saplings

The saplings to be planted on the eco forest berm are categorized into 5 groups—T1, T2 (tree), S (shrub), and Herb (ground cover), which will be combined and planted on berms. The size of saplings lies between 60cm to 120cm, optimal at 80cm. Fast growing trees will be mixed with normal-pace growing trees, so that the former can provide shading for the latter. Afterwards, the fast growing trees will be trimmed to let the slow growing species to be exposed to natural sunlight.


As soon as the saplings are planted, a good irrigation system will be significant. Hence, the saplings are usually suggested to get them planted before the rainy season comes, which provides good microclimates for the growth of plants.

The eco forest berm will require some maintenance during the first three years, including irrigation and trimming of vines. A healthy sapling can help ensure the sustainability of the eco forest berm and be adaptable to the future environmental challenges. After three years, maintenance requirement will be gradually reduced, but regular checkup will still be required.


PTT Protection Strip and Buffer Zone at different locations throughout Thailand have successfully upgraded the conditions and images of PTT depots. The unique eco forest strip planting has greatly enhanced the buffer landscape, bringing benefits to local communities, and maximizing potential for biodiversity and eco services for all users.

The installation of Miyawaki’s eco forest berm has created a unique fast growing of eco forest landscape, which has proven that this particular forest can shorten the growing time of 30 years forest to only 10 years.

The Metro Forest project, developed after the successful application of eco forest planting techniques by adapting the design to the many site constraints at PTT Protection Strip and Buffer Zone, adds another design perspective of the protection strips—aesthetic and human delight, and provides opportunities to create a dense and natural eco forest landscape for people to learn and enjoy the forest-like urban landscape. The Metro Forest and many other projects share different design intentions as to the protection strip but inspiring TK Studio to create more landscape design to adopt this planting technique and make it as a design signature of the studio.


Homepage: TK Studio

Lead Landscape Designer:

  • Mr. Tawatchai Kobkaikit: Lead Landscape Designer / Managing Director


  • Assistant Professor Dr. Angsana Boonyobhas

Landscape Design Team:

  • Miss Nantawan Sirisup, Miss Nottaporn Gatewattanatorn and Landscape Designer team
  • Miss Tiprada Tingkluab : Horticulturist

Client: PTT Public Company Limited

Photographer: Mr. Rungkit Charoenwat

Project location:

Phuket, Lampang, Phitsanulok, Den Chai Phrae, Si Racha Chonburi, Ban Rongpo Chonburi, Saraburi, Khon Kaen, Surat Thani, Songkhla, Khanom Nakhon Si Thammarat, Thailand

Design year: 2012-2018

Year Built: 2012-2018

Leave a Reply

Your email address will not be published. Required fields are marked *

Products by Streetlife