Severe river pollution creates a stressful environment for aquatic organisms, causing disturbances to their health and leading to their extinction. Thus, in this study, the stress responses of tolerant (Oreochromis niloticus) and sensitive (Cyprinus carpio) fish to river pollution in the Citarum River, Indonesia were investigated. The two groups of fish were exposed to varying levels and lengths of water pollution, their blood was sampled, and stress responses were identified. The red blood cells (RBC) count, haemoglobin (HGB), haematocrit (HCT), white blood cells (WBC) count, blood glucose levels, and derived haematological indices such as mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC), were measured. Significant changes in these indices, with tendential changes in RBC and HCT, were observed, indicating that stress responses had occurred in both groups of fish. The sensitive fish recorded more pronounced changes in their haematological activities, with greater amounts of blood parameters being altered in response to water pollution exposure. This result suggested that the sensitive fish were more susceptible to environmental stressors and were, therefore, more vulnerable to extinction in a polluted natural environment.

Oxygen plays a crucial role in aquatic ecosystem particularly for supporting aquaculture and hydropower. In freshwater, importance of oxygen is for metabolic respiration and balance for heterotrophic organisms. Oxygen is also involved in various chemical equations in which compounds influence each other. To prevent oxygen depletion, understanding the changes in DO and all interactions with other water qualities been reviewed with purposed to know aqueous systems work. Photosynthesis by phytoplankton is the main production of dissolved oxygen. Carbon dioxide as output from respiration of microorganisms and degradation of organic inputs and light as energy transformation of photosynthesis is needed in the process. The temperature level is involved as a determinant of gas solubility. There is also gas exchange from atmosphere to water as oxygen diffusion that move toward an equilibrium. However, dissolved oxygen absorption occurs in high demand in case an oxidizer in the degradation of organic matter which come into the reservoir. In eutrophic condition, the abundance of phytoplankton also requires oxygen for respiration, especially at night. The consumption of dissolved oxygen often spurs reservoir managers to monitor the input into the reservoir to build an aerator as a form of ensuring adequate dissolved oxygen circulation.

Restaurant wastewater in Indonesia comprises a variety of organic components that are difficult to degrade, such as COD, BOD, TSS, and oils and fats. Although grease traps are usually used to collect restaurant wastewater, the effluent still exceeds the applicable standards. For this reason, the combined technology of a two-chamber septic tank (ST) and a sequencing batch reactor (SBR) was chosen for this investigation. Both are biological treatment methods that involve an anaerobic and aerobic phase. This reactor will operate with a continuous influent flow that will be processed sequentially but discharged intermittently. The hydraulic retention time (HRT) of the ST-SBR was 12, 24, 36, and 48 hours, at aeration rates of 7 and 14 L/min, respectively. The results showed that introducing a Septic Tank increased the percentage of organic content removed and shortened the optimal HRT, resulting in a 24-hour optimal HRT and a 14 L/min aeration rate. With an average efficiency of 86.72% to 98.63% in removing organic components.

Indonesia’s batik industry is growing rapidly, including the segment specializing in natural dyes. However, this has produced concerns regarding sustainability deriving from, for example, the use of environmental pollutants in the field. This research aims to propose a set of preliminary indicators to facilitate the assessment of the sustainability of the natural-dye-based batik industry. We selected Batik Preketek, a company in Pekalongan City, Indonesia, as a case study and received support from representative panellists who were knowledgeable on these issues. We employed a mixed-methods approach, with data collected from field observations, laboratory analyses, structured and semi-structured interviews and secondary sources. The validated indicators were then applied to assess the current sustainability of batik production. The indicators used included five indicators from the environmental dimension, four from the economic dimension and six from the social dimension. Assessment of the company’s sustainability level produced a score of 77.50, indicating that it could be categorized as sustainable. The instrument developed was proved capable of capturing major sustainability issues and delivering prioritized strategies to improve sustainability.

Laju pertumbuhan penduduk yang semakin meningkat berbanding lurus dengan peningkatan timbulan sampah yang tentunya dapat menimbulkan pencemaran lingkungan dan masalah kesehatan. Banjarbakula merupakan kawasan yang terdiri dari Kota Banjarmasin, Kota Banjarbaru, Kabupaten Banjar, Kabupaten Barito Kuala, dan Kabupaten Tanah Laut. Untuk mengatasi persoalan persampahan di kawasan Banjarbakula, Dinas Pekerjaan Umum Penataan Ruang Provinsi Kalimantan Selatan melaksanakan perencanaan Tempat Pengolahan Sampah Terpadu (TPST) di Tempat Pembuangan Akhir (TPA) Regional Banjarbakula, Provinsi Kalimantan Selatan sebagai upaya pengurangan volume sampah sebelum dibuang ke TPA dengan program 3R. Tahapan perencanaan TPST ini dimulai dari tahap persiapan, survei lapangan, pengkajian berupa sumber sampah, wilayah perencanaan dan pelayanan, perencanaan teknis pengelolaan sampah di TPST, serta desain TPST. Rencana teknis operasional pengelolaan sampah terdiri dari penerimaan dan pembongkaran sampah, pemilahan sampah, pengepakan sampah, pencacahan dan pengayakan sampah, peuyeumisasi menjadi RDF/SRF, pengeringan dan pengepresan, penyimpanan dan pendistribusian. Luas rencana TPST Banjarbakula sesuai perencanaan yakni 3456 m2. TPST Regional Banjarbakula direncanakan hanya bisa mengolah sampah sebesar 40 ton/hari atau 160 m3/hari. Pengolahan sampah di TPST Regional Banjarbakula menggunakan metode peuyeumisasi menjadi RDF/SRF dan dipadatkan dalam bentuk briket.