Does Exploitation Reduce Carbon Storage? A Study on the Liao River Estuary Wetland

Abstract

There are many studies on carbon storage estimates, but only a few have shown an increase in carbon storage over time. The reasons for these increases are the positive ecological evolutions. The Liao River Estuary wetland is a unique area with “the more exploited, the higher carbon storage.” Based on remote sensing images and field surveys, we interpret the landscape type of the Liao River Estuary wetland. Furthermore, we estimate carbon storage and density evolution using the InVEST model. The results showed that 356.95 km2 of natural wetlands were transformed into artificial wetlands. The occupied natural wetlands were mainly tidal flats and reeds, which were mostly converted into paddy fields and aquaculture ponds. From 1980 to 2020, the changes in the carbon source and sink areas tended to be stable. The total carbon storage increased by 21.13×104 t. 1980–2010 was in the phase of land use exploitation, and the carbon storage increased by 57.37×104 t; 2010–2020 was in the ecological protection phase, and the carbon storage decreased by 36.25×104 t. It was because the core area with high carbon storage is well protected while exploiting the peripheral low-carbon area increased the carbon storage. It indicates that carbon storage capacity should not be directly related to the development degree and ecological environment value. Instead, it is necessary to calculate the area of natural and artificial wetlands and carbon storage separately, thereby confirming human disturbance and environmental value, etc. This paper demonstrates that development and carbon sequestration can be achieved simultaneously with proper land use planning, providing policy guidance for estuarine economic zones.