The Impact of Land Use and Biological Invasions on Ecological Service Values of Coastal Wetland Ecosystems: A Case Study in Jiangsu Province, China

Land use/land cover changes (LULCCs) and biological invasions significantly impact coastal wetlands (CWs) and their ecosystem services and functions. The exact impacts, however, are difficult to quantify and are often neglected in policymaking. The evaluation of ecological service value (ESV) is conducive to clarifying the ecological and environmental changes caused by LULCCs and biological invasions. The objective of this study was to investigate their impact on CWs in Jiangsu Province, China, and provide useful information and advice for policymakers concerned with sustainable development. In this paper, basic data were obtained through geographic information system technology, and CW ecosystems’ services were calculated via the ESV coefficients per unit area of different wetland types. Accordingly, this study found the current land use methods responsible for significant ecosystem disruption and reductions in the area of natural vegetation. Currently, the area of natural vegetation only accounts for 43% of the total area recorded in 1987. In 2018, the total ESV of wetland vegetation (<i>Spartina</i>, <i>Phragmites</i>, and <i>Suaeda</i>) was estimated to be USD 14.10 million, while that of farmland was USD 8.58 million, and that of forests was USD 2.09 million. Natural vegetation only covered 9% of the total land area but produced 60% of the total ESV. <i>Spartina alterniflora</i> exhibited the highest ESV per unit area, with USD 1.35 million. However, the CWs of Jiangsu Province have recently shown a shift in vegetation composition due to the invasion of <i>Spartina alterniflora</i>. Currently, the dominant species in these CWs are <i>Spartina alterniflora</i> and <i>Phragmites australis</i>, while the local population of <i>Suaeda salsa</i> has significantly declined. Therefore, it is necessary to strengthen the preservation and restoration of wetland vegetation, control the invasive potential of <i>Spartina alterniflora</i>, and consider the implementation of suitable protective measures for native plants.