UC Santa Barbara

Despite their protected status, forest reserves can be influenced by anthropogenic activities within and adjacent to reserve boundaries, resulting in environmental degradation and changes in forest cover. Long-term monitoring of environmental change within protected areas in a reliable and extensive manner is important given widespread, human-induced land-cover and land-use change. This study demonstrates the utility of optical satellite remotely sensed imagery and multi-temporal image analysis procedures for mapping and monitoring land cover and land use within cloud-prone and mountainous forest reserves and their environs in China and Ghana for the period of mid-1980s to 2018. The novel mapping and monitoring procedures yield extensive land-use dynamic information in a reliable manner by minimizing terrain-related illumination and cloud cover effects. Forest types and land-use are mapped in selected cloud-prone and mountainous forest reserves in China and Ghana to test the reliability of the optimized methods. By applying logical land-use transition rules and interpreting high spatial resolution satellite imagery, land-use changes and the anthropogenic activities associated with them are identified.

Vegetation and land-use types are mapped with moderate to high classification accuracies (64 to 94%) for study areas in China and Ghana. For Fanjingshan National Nature Reserve in China, 12 km^2 in land area is mapped as afforested bamboo and conifer lands associated with payment for ecosystem services programs, and over 25 km^2 is mapped as new development during 1995-2016. Forest area decreased by 9% for the 76 study reserves and environs in southern Ghana between 2000 and 2018. Substantial land changes associated with built development and agricultural expansion are observed in reserve environs within both study areas. Other anthropogenic activities including mining and plantation activities are identified in southern Ghana reserves, while afforestation activities associated with payment for ecosystem programs were predominant adjacent to Fanjingshan in China.

This study contributes to the land-cover and land-use mapping literature by developing and optimizing methods for extremely cloud prevalent and mountainous regions. A semi-automated mapping approach implemented on an open-access, user-friendly platform, similar to the workflow demonstrated in this study, increases the usability and transferability of such mapping techniques. Improved monitoring of other forested, mountainous, and cloud prevalent regions can benefit and inform protected area management and policy, long-term environmental change monitoring, and conservation effort assessment.