The mangrove ecosystems in East Java are widely exploited and converted for other land. Mangrove forests help decrease carbon dioxide concentration, are very efficient carbon sinks and store them in large quantities in biomass and sediments for a long time. This paper tries to understand the causes and effects of mangroves ecosystem damage on carbon stocks and absorption, with East Java, Indonesia as a case study. The Driver, Pressure, State, Impact and Response (DPSIR) framework, Analytic Hierarchy Process (AHP), and Partial Least Squares (PLS) used to identify and solve these problems. The result shows that the destruction of mangrove forests in East Java has occurred due to land conversion intensification. Accordingly, the mangroves’ average carbon sequestration and storage in East Java can be classified as moderate to low. Illegal logging is the leading cause, so there needs to be a clear policy that involves the government and the community. This result suggests that forming a strategy to prevent illegal logging and increase carbon sequestration and storage must be carried out, and community engagement in decision-making processes to protect and manage the mangrove forests.

Mangroves have a major role as carbon absorption and stock. However, this potential cannot be maximized, due to the high level of mangrove damage. The research question is the extent of the ability of mangroves to absorb carbon dioxide (CO2) and store it in the form of biomass. The purpose of this study was to determine the absorption ability and carbon stock of various types of mangove. The research location was chosen in Pejarakan village, Buleleng Regency, Bali Province, Indonesia as a case study. The method used is non-destructive to obtain diameter data at the height of mangrove trees, by collecting garbage and sediment samples manually on the floor of mangrove forests and to motivate the Government and local communities to restore mangrove forests. The results showed that the high density types of Sonneratia alba turned out to have the ability to absorb and store carbon, compared to other mangrove species. The results showed that S. alba is estimated to have the ability to absorb 57.60 tons of CO2 ha-1 which is equivalent to 15.71 tons C ha-1. While the lowest value is the Osbornia octodonta with the lowest density value. S. alba's ability to store carbon is 5.56 tons of CO2 ha-1 or equivalent to 1.52 tons C ha-1. The conclusion is that S. alba has the highest ability to absorb and store carbon.

The purpose of the research was to reorder the mangrove ecosystem restoration of coastal villages in order to overcome the damage coastal environments that have been damaged as a result of changes in land use. Data collection was done by using questionnaires and interviews with stakeholders. The study was conducted for three years from 2013 until 2016 with locations in Gresik and Malang districts. Data analysis was done by Partial Least Square and Analytical Hierarchy Process method to find out the priority order of restoration of the coastal ecosystem. In addition to SWOT analysis was conducted to determine the institutional capacity of the village and which would be responsible for restoring coastal ecosystems. The results show that the order of handling on coastal ecosystem damage was firstly mangrove forest, secondly coral reef, thirdly estuary area and fourthly seagrass area. Institutions responsible for handling the level of damage to coastal ecosystems was a village government, which was supported by the regional work units (SKPD) at the district level. Besides that, the role of government, private and community became the key to success on the successful implementation of restoration. Technical manual implementation of Coastal Ecosystem restoration-based co-management was necessary for the restoration of coastal ecosystems.

Coastal zones play an important role in providing various valuable ecosystem services. However, it is also sensitive and vulnerable to environmental changes due to human overpopulation and interactions between the land and ocean. Pramuka Island, located in the Kepulauan Seribu National Park, can potentially be developed as a marine ecotourism area. Some coastal ecosystems on the island can be promoted as tourist attractions. The existing coral reefs, sea turtles, and mangrove forests are potential resources that can be used as tourism objects. However, the different objectives of marine ecotourism and ecosystem conservation might raise management conflicts in relation to land use on the island. This research aims to propose a strategy for the management of Pramuka Island by synergizing the conservation interest with the development of marine ecotourism area. It employs the ecology based Management-Driver Pressure State Ecosystem Service and Response (EBM-DPSER). The results showed that government policy is in need to reduce conflicts between conservation and economic interests.

The amount of waste in Indonesia is estimated to reach 68 million tons in 2019, of which 9.52 million tons is a plastic waste. With this amount, Indonesia is ranked second in the world as the largest producer of plastic waste. One area that suffers from plastic waste is the coastal area. This plastic waste is difficult to decompose and cause environmental problems. Likewise, it happened on the Tambaan coast in Tambaan sub-district, Panggungrejo subdistrict, Pasuruan city. Currently, accumulation of plastic waste is evident throughout the coastal area. The accumulation of scattered plastic waste and its proximity to the residents’ settlements has become a hotbed of mosquitoes and caused a pungent smell. The Serving Doctoral Program at Universitas Brawijaya offers a solution to process plastic waste into fuel oil such as diesel, kerosene, and premium. The technology used was Muryani’s distillation from Wlingi, Blitar Regency. The technology can change certain types of plastic waste to produce fuel. Karang Taruna Bina Hang Tuah was acted as a reliable partner to assist the implementation of the technology on site. This study aims to strengthen the capacity of Karangtaruna in Tambaan Village to be more concerned about the environmental problems of Tambaan beach by processing waste that has been polluted by plastic waste. The results of plastic waste treatment showed that 10 kg of dried plastic waste can be transformed into diesel, premium and kerosene with the efficiency value of 60%, 35%, and 15%, respectively.