The growth of urbanization, industrialization, and economic development in many areas in Indonesia contributes to the rise of particulate matter (PM) in the atmosphere. PM is strongly correlated with the severe air pollution that can lead to several health problems and early mortality. Other than continuous concentration monitoring, a good understanding of chemical characteristics and sources of PM is important for effective management and mitigation of air pollution. The aim of this study was to summarize the spatial distribution of the PM (PM2.5 and PM10) concentration level, chemical characteristics, and sources apportionment in several cities in Indonesia based on systematic Scopus and Google searches for the period of publication year between 2008 to 2019. The studies of 10 cities showed most of the cities’ PM2.5 and PM10 average concentration have exceeded the annual average standard of both Indonesian regulation and WHO standards. Generally, traffic emissions were the majority sources, followed by biomass burning and dust emission. Forest and peat fires did contribute to high biomass burning emission in the downwind cities. The findings help to give the image of the status and the nature of particulate air pollution problems in Indonesia. Current issues and future research needs were also discussed.

The tremendous quantity of waste produced from construction and demolition is a major cause of environmental degradation. This quantity tends to increase due to the rapid growth of building development and renovation. Meanwhile, construction waste management is a complex and costly process due to the fact that it requires different kinds of resources such as money, land, and technology. It is often ignored by all project participants even though it is an essential element of construction project management. However, it has been discovered that modern construction waste management is structured based on the concept of circular economy which focuses on eliminating construction waste and maximizing the value of materials. Therefore, this research proposes an innovative framework to implement the circular economy using building information modeling (BIM) in order to improve the construction waste management process. This involved a thorough review of past literature to identify the implementation of the concept of circular economy, waste management, and the application of BIM, also the research gaps observed were used to develop the functionality of the proposed framework. The five functionalities include (1) visualization and data integration, (2) direct construction waste quantity take-off, (3) BIM-based sorting system and selection of appropriate disposal parties, (4) estimating cost and schedule of waste disposal, and (5) simulation and monitoring report. This BIM system was designed to analyze material waste, quantity, disposal time, and waste treatment based on project conditions, material quantities, and schedule. It can also be used to plan and monitor the construction waste process, thereby making it possible to avoid the disruption of productivity and project time usually caused by unplanned waste management activities. Moreover, the proposed on-site sorting system also has the ability to facilitate the adoption of the circular economy concept during the construction phase.

Wastewater contains water, nutrients, and energy resources, which can be recovered for human activities. Product from wastewater is one of the solutions to provide energy and food security amidst the looming energy and fertilizer crisis. Unfortunately, wastewater treatment plants in developing countries are often designed not to accommodate the concept of resource recovery. Currently, there is a real lack of feasibility analysis of upgrading existing wastewater treatment plants to accommodate the concept of resource recovery. Therefore, this study aims to determine the resource recovery potential in existing wastewater treatment plants in Yogyakarta and identify their limitations for resource recovery. Two wastewater treatment plants in Yogyakarta were assessed, one with anaerobic treatment, the other with stabilization ponds. The feasibility is assessed by the parameter of wastewater flow, organics, nutrients, and microbiology compounds. The findings of this study will be beneficial for a regional management standpoint to consider the most suitable strategy for wastewater management in Yogyakarta.

Declining natural resources and increasing environmental contamination due to human activities trigger people to consider a sustainable way to solve two problems in a solutive practice. Many households in Indonesia mostly discharge their greywater directly to the surface water, which pollutes the water and environment around it. On the other hand, the amount of potential water resources is declining nationwide, resulting in high pollution levels and require the high cost of water treatment to purify the water. To reduce the pollution load as well as to provide alternative water for indoor and outdoor use, it is necessary to find the most effective treatment. Greywater treatment by using plants (phytotechnology) combined with solar UV system is one of the breakthroughs that meet the criteria of low cost, simple in operation and maintenance, as well as energy saving. This paper presents the result of the combined treatment of phytoremediation and solar UV system as a very effective treatment to treat greywater. The treatment design consists of a collection chamber, sedimentation, filter, phytoremediation, and solar UV disinfection chamber. The treated water quality met the requirements of the Provincial Regulation of Central Java No. 5 of 2012 and class 3 standard (water for cultivation of plants and fisheries) of Indonesian Government Regulation No. 82 of 2001, but does not yet meet the standard for toilet flushing water. This result showed that the treatment of greywater by using plants and solar UV treatment is still facing some challenges to increase the intake of its treated water for indoor and outdoor water used within a household.

Ruang Terbuka Hijau (RTH) sangat penting untuk suatu perkotaan karena selain menjadi fungsi ekologis, RTH juga dapat memelihara fungsi sosial budaya, dan estetika suatu wilayah perkotaan. Pembuatan RTH di RW 02 Kampung Tulung, Kecamatan Magelang Tengah, Kota Magelang dinilai penting untuk mengimbangi tingginya densitas penduduk ditambah dengan adanya beberapa bengkel motor dan mobil yang berpotensi pada pencemaran udara yang tinggi. Selain itu, RW ini minim ruang publik yang dapat mendukung sarana berinteraksi warga. Pembangunan RTH ini bertujuan untuk merancang dan membangun RTH yang dapat memenuhi fungsi ekologis, ekonomi, sosial-budaya, dan estetik. Dasar perencanaan kebutuhan luas RTH minimum dihitung dengan metode berdasarkan jumlah penduduk yang merujuk pada Peraturan Menteri Pekerjaan Umum No. 05 tahun 2008. Konsep yang digunakan yaitu pengembangan RTH eksisting dengan penambahan tanaman fungsional, fasilitas dan teknologi ramah lingkungan pada lahan  seluas 461,58 m2. Teknologi ramah lingkungan yang dibangun berupa 48 lubang resapan biopori sebagai kompensasi resapan untuk air limpasan dari lahan yang diperkeras untuk fasilitas olahraga. Fasilitas bangku, mainan, dan rumah organik dibangun guna mendukung fungsi sosial budaya, ekonomi dan estetik. RTH yang telah dibangun menjadi pusat kegiatan warga dalam bidang kesehatan dan inovasi serta berhasil menjadi Juara Harapan 1 untuk lomba taman se Kota Magelang tahun 2019 yang diselenggarakan oleh Badan Lingkungan Hidup (BLH) Kota Magelang.