[Refined Simulation and Analysis of Land Use Type Evolution in Heilongjiang Province]

Heilongjiang Province， as an important state-owned forest area and commercial grain base in China， analyzing its land use change and exploring the spatial differentiation of land use is of great significance for understanding the spatiotemporal evolution mechanism of regional land use， carbon balance， and scientific territorial spatial planning. Based on the land use type data of Heilongjiang Province from 1985 to 2020， land use categories were systematically classified into 11 classes. Notably， the primary forest land category was further refined into shrubland， deciduous broad-leaved forest， evergreen coniferous forest， deciduous coniferous forest， and mixed coniferous-broad-leaved forest. This detailed classification framework facilitated a comprehensive analysis of land use area dynamics and land use transitions in Heilongjiang Province over the past 35 years. Land use changes in Heilongjiang Province from 2020 to 2070 under natural development and policy-driven scenarios were simulated using the Patch-generating Land Use Simulation （PLUS） model. The dynamic forest fragmentation index （ΔFFI） was calculated to quantify the effectiveness of policy interventions， and the Geodetector method was employed to evaluate the explanatory power of various driving factors on the spatial differentiation of land use patterns. The results show that： ① During the period from 1985 to 2020， among the major land use types in Heilongjiang Province， the area of cropland increased while the areas of deciduous broad-leaved forest and deciduous coniferous forest decreased. ② Changes in the areas of various land-use types were mainly due to mutual transfers involving cropland. The conversion of deciduous broad-leaved forest to cropland resulted in an expansion of cropland area. Conversely， the conversion of cropland to impervious surfaces and shrubland was the primary driver of the expansion of both land use types. ③ Soil type and population exhibited the greatest explanatory power for the spatial differentiation of land use types in Heilongjiang Province in 2020， and the explanatory power of multi-factor interactions was significantly stronger than that of individual factors. DEM， population， and GDP were the dominant factors driving the expansion of various land use types， while transportation networks played a decisive role in impervious surface expansion. ④ Significant differences in projected land use changes and forest fragmentation dynamics under the two scenarios suggest that policy factors play a critical role in shaping future land use patterns in Heilongjiang Province.