Aquatic Ecosystems: Biodiversity, Conservation, Human Impacts, and Global Importance

Abstract

This semi-review considers aquatic ecosystems as life-support systems that sustain biodiversity, climate regulation, food security, environmental health, and economic activity. It brings together scientific literature on marine, coastal, estuarine, swamp, lake, river, and wetland environments with official statistics from the East Kalimantan Province in Figures series for 2020-2026. Using a narrative-critical approach, the review examines community structure, ecological functions, ecosystem services, human pressures, conservation responses, and priorities for future research. The evidence shows that aquatic ecosystems support substantial genetic, species, and habitat diversity, yet pollution, overfishing, land-use change, flow fragmentation, invasive alien species, and climate change increasingly act together to erode ecosystem condition. East Kalimantan provides a useful regional illustration: the province contains major lake systems in Kutai Kartanegara and Kutai Timur, extensive river networks, and in 2024 produced 216.04 thousand tonnes from capture fisheries and 245.16 thousand tonnes from aquaculture. These ecological assets and production figures make clear that conservation cannot be separated from fisheries governance, water-quality management, habitat recovery, and cross-sectoral policy. The review therefore emphasizes ecosystem-based management, stronger links between biological monitoring and spatial data, wetland and coastal restoration, and sustained collaboration among stakeholders as practical foundations for adaptive aquatic conservation.