Subchapter 6a: Invasive species Globally, the spread of non-indigenous species (NIS) continues, exacerbated by climate change and human activities, negatively affecting some of the most vulnerable marine ecosystems. The introduction of NIS continues to negatively impact native species and habitats, affecting global ecological, socioeconomic, cultural and human health outcomes. A lack of long-term studies on NIS impacts hinders risk identification and reduces the effectiveness of post-invasion management efforts. Read more about Subchapter 6a arrow_forward
Subchapter 6b: Erosion and sedimentation Global and regional coastal erosion and sedimentation assessments based on satellite data have proliferated since the mid-2010s, offering insights into trends and patterns of change. However, uncertainties and limitations of satellite-derived methods must be carefully considered. Nature-based solutions, such as the renaturalization of floodplains and intertidal areas, are increasingly being applied to catchments and coastal regions in the northern hemisphere. While such measures can improve long-term resilience, they may lead to rapid short-term changes. Read more about Subchapter 6b arrow_forward
Subchapter 6c: Marine infrastructure outside of coastal areas Marine infrastructure development beyond coastal areas has intensified pressures on marine ecosystems, including marine noise, seawater quality and changes to hydrodynamic circulation. Over the next 10 to 20 years, marine infrastructure development presents major challenges, especially with respect to climate change, but also offers opportunities for innovation, sustainable growth, enhanced security and greater resilience. Read more about Subchapter 6c arrow_forward
Subchapter 6d: Cumulative effects Cumulative effects assessments, also known as cumulative impact assessments, have been applied continuously since the publication of the second World Ocean Assessment. These assessments are being used within national jurisdictions to inform decision-making. Lessons learned from the application of cumulative effects assessment can guide further development of assessment approaches. Read more about Subchapter 6d arrow_forward
Subchapter 6e: Pollution Chemicals and other materials from land-based sources continue to impact ocean ecosystems. There has been a decline in mercury emissions and precipitation, along with reductions in emissions to air of some organic compounds, in certain regions. Growing demand for non-carbon electricity has resulted in an increased reliance on nuclear power, which is likely to lead to higher radioactive discharges. Global plastic waste emissions continue to rise, with substantial leakage due to mismanaged waste, microplastic abrasion and loss, littering and marine activities. These plastics, especially microplastics, impact all marine ecosystems, with over 4,000 species affected. Read more about Subchapter 6e arrow_forward
