The Impact of Human Activities on Net Primary Productivity in a Grassland Open-Pit Mine: The Case Study of the Shengli Mining Area in Inner Mongolia, China

Dynamics of carbon sequestration in vegetation affected by large-scale surface coal mining and subsequent restoration

Surface coal development activities include mining and ecological restoration, which significantly impact regional carbon sinks. Quantifying the dynamic impacts on carbon sequestration in vegetation (VCS) during coal development activities has been challenging. Here, we provided a novel approach to assess the dynamics of VCS affected by large-scale surface coal mining and subsequent restoration. This approach effectively overcomes the limitations imposed by the lack of finer scale and long-time series data through scale transformation. We found that mining activities directly decreased VCS by 384.63 Gg CO2, while restoration activities directly increased 192.51 Gg CO2 between 2001 and 2022. As of 2022, the deficit in VCS at the mining areas still had 1966.7 Gg CO2. The study highlights that complete restoration requires compensating not only for the loss in the year of destruction but also for the ongoing accumulation of losses throughout the mining lifecycle. The findings deepen insights into the intricate relationship between coal resource development and ecological environmental protection.

Estimation of Ecosystem Services Value at a Basin Scale Based on Modified Equivalent Coefficient: A Case Study of the Yellow River Basin (Henan Section), China

The value of ecosystem services is an extremely important parameter that reflects regional ecological benefits and resources. Estimating the value of ecosystem services is essential for regional land-use optimization, ecological construction, and biodiversity protection. In this study, Landsat-TM/ETM remote sensing images were used to analyze land-use data in 1990, 2000, 2010, and 2020 of the Yellow River Basin (Henan section), China, defined by natural boundaries. An equivalent factor method was used to construct a model to calculate the ecosystem services value that introduced grain yield, regional difference coefficient, and social development stage coefficient. Thus, land-use changes and evolution of ecosystem services values in the Yellow River Basin (Henan section) in the past 30 years were analyzed. Land use in the basin changed significantly from 1990 to 2020. Except for an increase in area of construction land, areas of other land-use types decreased. Cultivated land area first increased and then decreased, whereas the water area first decreased and then increased. The total value of ecosystem services in the study area fluctuated but increased overall by 43.82 × 10⁸ USD in the past 30 years. Spatially, the total value of ecosystem services was high in the southwest and low in the northeast. Among individual ecosystem service values, water conservation, gas regulation, and climate regulation accounted for a relatively high proportion of the total value. Regulation services were the main ecosystem service functions, followed by support and supply services, with cultural services accounting for the lowest proportion. Sensitivity coefficients of different land types in different periods were all less than one. Therefore, the value coefficients were reasonable, and the results were consistent with the actual situation of the study area. The study improves the method to estimate the ecosystem services value of the basin and also indicates ways to support ecological protection of the Yellow River Basin (Henan section), China.

Study on Ecological Loss in Coal Mining Area Based on Net Primary Productivity of Vegetation

Opencast mining contributes to the severe disturbance of vegetation and serious damage to the ecological environment. Scientific assessment of the ecological losses may provide guidance for the sustainable land use in mining areas. This study uses the Carnegie Ames Stanford Approach (CASA) model to estimate the net primary productivity (NPP) of vegetation in the Pingshuo mining area from 2006 to 2020 and uses statistical analysis and mathematical models to study the impact of mining and land reclamation on NPP. The results show that NPP decreased slowly at a rate of 0.809 gC/(m2·month) per year. In 2006, the urban area of Pinglu and the opencast coal mining area were located in the western part of the study area, while the eastern part was distributed with a large amount of grassland, forested and cultivated land, and the NPP showed a high pattern in the east and low in the west. With the continued eastward movement of Antaibao and Anjialing mining areas, as well as the construction and continuous westward expansion of the East opencast mine, the pits of all three opencast mines moved to a central location in 2020, changing the spatial distribution of NPP to high in the surroundings and low in the middle. The NPP within the three opencast mines decreased significantly, but the change in NPP increased from −7.34 gC/(m2·month) to 7.15 gC/(m2·month) as the reclamation area increased, indicating that mining increased ecological losses while land reclamation mitigated them. The variation of NPP within 600 m outside the mining area is 2.06~7.45 gC/(m2·month), and 0.11~1.00 gC/(m2·month) from 600 m to 1000 m, indicating that NPP is sensitive to the influence of mining. The results may provide guidance for further analysis of the impact of mining on local environments and exploration of more appropriate land reclamation measures.