There are 3 ecosystem components in the watershed, namely abiotic, biotic, and culture. All three work together to form a unity which is the basis of whether the management of the watershed is running well or not. Each ecosystem has different problems so that management is also different.
Watershed problems in terms of abiotic components are broad enough to only be chosen based on upstream and downstream causal impacts. Some issues that become important points are erosion-sedimentation, flooding, and water quality. These three problems become important keys in the problems in the watershed and clearly the impacts caused by a single upstream-downstream unit. Erosion and excessive sedimentation problems have an impact on the overall condition of the watershed. If erosion is high enough in the upstream area, the downstream area of sedimentation that occurs is quite large, it has an impact on downstream flooding due to shallow river channels and reduced water quality due to increased turbidity thereby reducing circulation of important elements for aquatic biota.
The initial stage in checking is quite easy if the river and estuary is quite muddy, the erosion process is quite intensive upstream. In addition, it is necessary to conduct a geomorphological study of soil to determine the potential for erosion and landslides in the watershed to contribute to coastal sediment. The management that needs to be done is the conservation of the upstream area which has its conservation function function by replanting endemic plants in the study location and strengthening the rules for the conversion of the upstream protected land function. In addition it can be done by building both large-scale bending reservoirs and check dams on a small scale to reduce and inhibit the rate of sedimentation so as not to overflow to the watershed coast. Management for erosion has also passed to flood management both conservation of upstream areas and DAM development because of a unified process for water and soil conservation. However, there are additions to the downstream area so as to avoid flooding, namely by making embankments and strengthening the rules in arranging residential areas that consider river borders. In addition, it is also necessary to do watershed morphometry, especially in the form of watershed studies to estimate the potential for flooding in watersheds in the initial baseline study. This is important in the process of determining the construction of a weir.
Water quality issues also become important when surface water in the watershed is utilized. The natural conditions of a watershed also produce pollution naturally but when there is human activity in it that pollutes the watershed will have an impact on the whole section. The pattern that occurs in the downstream watershed is the accumulation of various kinds of pollutants so that the water quality is the worst. Therefore, prevention needs to be carried out in the upstream and middle parts so that the downstream water quality becomes good. This can be done by making rules related to waste management and waste disposal. Waste management can be done by providing a place for treating waste or a place for accumulating waste so that the community does not make waste to the river. Besides that, it is also in the form of strengthening the rules in the form of companies that dump waste into the river to reduce levels of waste below the river quality. Based on this plan, it can reduce the potential for decreasing water quality in the coastal watershed.
Biotic components in the form of flora and fauna are important because they are a natural indicator of a good or problematic watershed. The focus of fauna is especially on aquatic fauna which is a bio indicator because if the condition of biodiversity waters is low and adaptability is minimal then the condition of the watershed is problematic. The withdrawal of the problem from the low biodiversity and low adaptability can be identified by both physical, chemical and biological water quality tests which are then continued by identifying the source of the pollution. For flora is more emphasized in the endemic flora of the upstream region if it decreases due to changes in land use, it affects the conditions in the coastal watershed, especially the increase in sedimentation. Management that can be done based on flora and fauna indicators is the making of policy rules in maintaining the sustainability of aquatic fauna by reducing the level of waste pollution and for flora with a policy prohibiting changes in upstream land use.
The cultural component has a very strong influence on watershed and coastal issues. Keywords in the cultural aspect are land specifically changes in land use due to human activities. Changes in upstream land have a major impact on coastal areas, both flooding and increased sedimentation. In addition, due to human activities caused pollution in the watershed that accumulates in coastal areas. This is very different if it is related to local customs and customs that apply to certain communities.