Impacts of Human Activities on Ecosystem Service Value in Arid and Semi-Arid Ecological Regions of China

Terrestrial protected areas: Understanding the spatial variation of potential and realized ecosystem services

Terrestrial protected areas (TPAs) have become a keystone in nature conservation and environmental policy-making because they provide a potpourri of ecosystem services-benefits that are foundational for human existence and well-being. The intensity of ecosystem services production (i.e., potential) and use (i.e., realized) from a TPA depends on several variables such as ecosystem type, TPA size, population in the region, and development infrastructure. However, little is known about how ecosystem services intensity varies in relation to these variables. The TPAs provide a rich setting to investigate these relationships in support of better management for both TPAs and ecosystem services. Here, using the Co$ting Nature model, I map the potential and realized ecosystem services intensity from 140 of Pakistan's TPAs. To ascertain the direct impacts on realized ecosystem services, I use ArcGIS and InVEST tools to infer three spatial variables: TPA size (area), TPA distance from the nearest urban center, and visitation rates to the TPA. Results from the statistical analyses show that potential and realized ecosystem services are positively and significantly correlated, meaning increased supply results in more use. Yet, both are negatively correlated with TPA size and distance from the urban centers. Finally, a multivariate regression analysis is conducted considering potential ecosystem services and the selected three spatial variables as predictors for realized ecosystem services. The analysis indicates that potential ecosystem services and the size of a TPA are both significant for realized ecosystem services, with the potential services positively and TPA size negatively correlated with realized ecosystem services. The data generated and the results obtained in the study can inform the protection, stewardship, and expansion of TPAs at national and global scales.

Monitoring 3D Changes in Urban Forests Using Landscape Metrics Analyses Based on Multi-Temporal Remote Sensing Data

Rapid urbanization is causing changes in green spaces and ecological connectivity. So far, urban ecosystem research has mainly focused on using landscape metrics (LM) in two-dimensional (2D) space. Our study proposes three-dimensional (3D) measures of urban forests (UF) and LM calculations using LiDAR technology. First, we estimated the UF volume of Krakow (Poland) and the distribution of vegetation (low, medium, high) using a voxel-based GEOBIA approach based on the ALS LiDAR point cloud, satellite imagery, and aerial orthophotos at specific timestamps: 2006, 2012, 2017. Then, the appropriate landscape metrics were selected (NP, AREA_MN, CONTIG_MN, LPI, PARA_MN, SPLIT, MESH, PD, DIVISION, LSI) to quantify the differences between the 2D- and 3D-derived vegetation structures and detect changes in the urban landscape. The results showed that areas with low vegetation decreased due to the expansion of built-up areas, while areas with medium and high vegetation increased in Krakow between 2006, 2012, and 2017. We have shown that the lack of information on the vertical features of vegetation, i.e., 2D greenery analysis, leads to an overestimation of landscape connectivity. In the 3D vegetation classes, it was observed that low vegetation was the best connected, followed by high vegetation, while medium vegetation was dispersed in the city space. These results are particularly relevant for the urban environment, where the distribution of green space is crucial for the provision of ecosystem services.