Landscape Health Assessment of Suburban Forest Park: A Case Study Based on Multiple Sampling Units and Functional Characteristics

Assessing the landscape health of suburban forest parks is a prerequisite for achieving the dual objectives of forest resource conservation and recreational services. However, studies that analyze landscape health in suburban forest parks at a landscape scale by subdividing the landscape into multiple sampling units and adopting a multi-functional perspective have been limited. This study focuses on Xiqiao Mountain National Forest Park and establishes a landscape classification system and indices, taking into account its multifunctionalities. The study employs the entropy weight method to determine indicator weights and utilizes grid analysis and spatial interpolation to analyze the spatial distribution of landscape health under multiple sampling units and functionalities, along with the differences in its impact and influencing factors. The results indicate that: (1) regions with "very poor" and "poor" landscape health grades under multiple sampling units and functionalities exhibited a sheet-like distribution pattern, covering approximately 69.46% to 98.86% of the total area. In contrast, regions with "very good" and "good" grades are primarily located in block-like or linear patterns in the northern, central, and southern regions of the park, accounting for approximately 1.07% to 17.20% of the total area. (2) The area ratios of "very good" and "good" landscape health grades for recreational landscapes under varying sampling units were consistently higher than those of the same grades for eco-conservational landscapes, with a 5.03%-15.43% difference. This suggests a greater emphasis on recreational functionality. (3) The impact of three different sampling unit sizes on the landscape health of Xiqiao Mountain National Forest Park under multifunctionalities is not significantly different; however, the forest/non-forest area ratio and quantity ratio are vital factors influencing its landscape health. The landscape health assessment results, considering multiple sampling units and functionalities in this study, serve to provide technical method support and practical case references for the planning, construction, and management decision-making of suburban forest parks.