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.