Research Framework for the Response of Ecological Security Patterns to Territorial Spatial Utilization Transformation: Taking the Qinba–Dabie Convergence Area in China as an Example

China is at a critical stage in the coordinated promotion of ecological civilization construction, rural revitalization, and new urbanization strategies. How to scientifically coordinate the transformation of territorial spatial utilization (TSU), such as that of ecology–agriculture–urban spaces, and to build an ecological security pattern (ESP) has emerged as a critical task facing regional sustainability. To address the above problem, this study constructs a research framework to reveal the response characteristics of ESP to TSU transformation by adopting the source–surface–flow continuous field model and geographic grid analysis methods. Taking the Qinba–Dabie convergence area in China, with typical transitional characteristics and regional representativeness, as the study area, this study quantitatively analyzes the spatiotemporal evolution of the comprehensive index of TSU degree, as well as the ecological source, resistance, and flow indices across the whole territory. With the geographic grid method adopted to unify the spatial analysis grain between ESP and TSU transformations, this study further explores the response characteristics of ESP under TSU transformation. The main study findings are presented as follows: With the transformation of TSU, ESP elements such as the ecological source index, resistance index, and flow index exhibited significant spatial differentiation, and a nonlinear relationship could be observed between the TSU degree index and the ESP elements. On this basis, this study further explores and constructs a zoning method system for regional TSU control oriented to ESP, formulates targeted protection and restoration strategies, offering theoretical and practical references for the scientific compilation of territorial spatial planning and the conservation and restoration of ESP.